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v3.1
   1/*
   2 * USB hub driver.
   3 *
   4 * (C) Copyright 1999 Linus Torvalds
   5 * (C) Copyright 1999 Johannes Erdfelt
   6 * (C) Copyright 1999 Gregory P. Smith
   7 * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
   8 *
   9 */
  10
  11#include <linux/kernel.h>
  12#include <linux/errno.h>
  13#include <linux/module.h>
  14#include <linux/moduleparam.h>
  15#include <linux/completion.h>
  16#include <linux/sched.h>
  17#include <linux/list.h>
  18#include <linux/slab.h>
  19#include <linux/ioctl.h>
  20#include <linux/usb.h>
  21#include <linux/usbdevice_fs.h>
  22#include <linux/usb/hcd.h>
  23#include <linux/usb/quirks.h>
  24#include <linux/kthread.h>
  25#include <linux/mutex.h>
  26#include <linux/freezer.h>
 
  27
  28#include <asm/uaccess.h>
  29#include <asm/byteorder.h>
  30
  31#include "usb.h"
  32
  33/* if we are in debug mode, always announce new devices */
  34#ifdef DEBUG
  35#ifndef CONFIG_USB_ANNOUNCE_NEW_DEVICES
  36#define CONFIG_USB_ANNOUNCE_NEW_DEVICES
  37#endif
  38#endif
  39
  40struct usb_hub {
  41	struct device		*intfdev;	/* the "interface" device */
  42	struct usb_device	*hdev;
  43	struct kref		kref;
  44	struct urb		*urb;		/* for interrupt polling pipe */
  45
  46	/* buffer for urb ... with extra space in case of babble */
  47	char			(*buffer)[8];
  48	union {
  49		struct usb_hub_status	hub;
  50		struct usb_port_status	port;
  51	}			*status;	/* buffer for status reports */
  52	struct mutex		status_mutex;	/* for the status buffer */
  53
  54	int			error;		/* last reported error */
  55	int			nerrors;	/* track consecutive errors */
  56
  57	struct list_head	event_list;	/* hubs w/data or errs ready */
  58	unsigned long		event_bits[1];	/* status change bitmask */
  59	unsigned long		change_bits[1];	/* ports with logical connect
  60							status change */
  61	unsigned long		busy_bits[1];	/* ports being reset or
  62							resumed */
  63	unsigned long		removed_bits[1]; /* ports with a "removed"
  64							device present */
 
 
  65#if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
  66#error event_bits[] is too short!
  67#endif
  68
  69	struct usb_hub_descriptor *descriptor;	/* class descriptor */
  70	struct usb_tt		tt;		/* Transaction Translator */
  71
  72	unsigned		mA_per_port;	/* current for each child */
  73
  74	unsigned		limited_power:1;
  75	unsigned		quiescing:1;
  76	unsigned		disconnected:1;
  77
  78	unsigned		has_indicators:1;
  79	u8			indicator[USB_MAXCHILDREN];
  80	struct delayed_work	leds;
  81	struct delayed_work	init_work;
  82	void			**port_owners;
  83};
  84
  85static inline int hub_is_superspeed(struct usb_device *hdev)
  86{
  87	return (hdev->descriptor.bDeviceProtocol == 3);
  88}
  89
  90/* Protect struct usb_device->state and ->children members
  91 * Note: Both are also protected by ->dev.sem, except that ->state can
  92 * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
  93static DEFINE_SPINLOCK(device_state_lock);
  94
  95/* khubd's worklist and its lock */
  96static DEFINE_SPINLOCK(hub_event_lock);
  97static LIST_HEAD(hub_event_list);	/* List of hubs needing servicing */
  98
  99/* Wakes up khubd */
 100static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
 101
 102static struct task_struct *khubd_task;
 103
 104/* cycle leds on hubs that aren't blinking for attention */
 105static int blinkenlights = 0;
 106module_param (blinkenlights, bool, S_IRUGO);
 107MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
 108
 109/*
 110 * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
 111 * 10 seconds to send reply for the initial 64-byte descriptor request.
 112 */
 113/* define initial 64-byte descriptor request timeout in milliseconds */
 114static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
 115module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
 116MODULE_PARM_DESC(initial_descriptor_timeout,
 117		"initial 64-byte descriptor request timeout in milliseconds "
 118		"(default 5000 - 5.0 seconds)");
 119
 120/*
 121 * As of 2.6.10 we introduce a new USB device initialization scheme which
 122 * closely resembles the way Windows works.  Hopefully it will be compatible
 123 * with a wider range of devices than the old scheme.  However some previously
 124 * working devices may start giving rise to "device not accepting address"
 125 * errors; if that happens the user can try the old scheme by adjusting the
 126 * following module parameters.
 127 *
 128 * For maximum flexibility there are two boolean parameters to control the
 129 * hub driver's behavior.  On the first initialization attempt, if the
 130 * "old_scheme_first" parameter is set then the old scheme will be used,
 131 * otherwise the new scheme is used.  If that fails and "use_both_schemes"
 132 * is set, then the driver will make another attempt, using the other scheme.
 133 */
 134static int old_scheme_first = 0;
 135module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
 136MODULE_PARM_DESC(old_scheme_first,
 137		 "start with the old device initialization scheme");
 138
 139static int use_both_schemes = 1;
 140module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
 141MODULE_PARM_DESC(use_both_schemes,
 142		"try the other device initialization scheme if the "
 143		"first one fails");
 144
 145/* Mutual exclusion for EHCI CF initialization.  This interferes with
 146 * port reset on some companion controllers.
 147 */
 148DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
 149EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
 150
 151#define HUB_DEBOUNCE_TIMEOUT	1500
 152#define HUB_DEBOUNCE_STEP	  25
 153#define HUB_DEBOUNCE_STABLE	 100
 154
 155
 156static int usb_reset_and_verify_device(struct usb_device *udev);
 157
 158static inline char *portspeed(struct usb_hub *hub, int portstatus)
 159{
 160	if (hub_is_superspeed(hub->hdev))
 161		return "5.0 Gb/s";
 162	if (portstatus & USB_PORT_STAT_HIGH_SPEED)
 163    		return "480 Mb/s";
 164	else if (portstatus & USB_PORT_STAT_LOW_SPEED)
 165		return "1.5 Mb/s";
 166	else
 167		return "12 Mb/s";
 168}
 169
 170/* Note that hdev or one of its children must be locked! */
 171static struct usb_hub *hdev_to_hub(struct usb_device *hdev)
 172{
 173	if (!hdev || !hdev->actconfig)
 174		return NULL;
 175	return usb_get_intfdata(hdev->actconfig->interface[0]);
 176}
 177
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 178/* USB 2.0 spec Section 11.24.4.5 */
 179static int get_hub_descriptor(struct usb_device *hdev, void *data)
 180{
 181	int i, ret, size;
 182	unsigned dtype;
 183
 184	if (hub_is_superspeed(hdev)) {
 185		dtype = USB_DT_SS_HUB;
 186		size = USB_DT_SS_HUB_SIZE;
 187	} else {
 188		dtype = USB_DT_HUB;
 189		size = sizeof(struct usb_hub_descriptor);
 190	}
 191
 192	for (i = 0; i < 3; i++) {
 193		ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 194			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
 195			dtype << 8, 0, data, size,
 196			USB_CTRL_GET_TIMEOUT);
 197		if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
 198			return ret;
 199	}
 200	return -EINVAL;
 201}
 202
 203/*
 204 * USB 2.0 spec Section 11.24.2.1
 205 */
 206static int clear_hub_feature(struct usb_device *hdev, int feature)
 207{
 208	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 209		USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
 210}
 211
 212/*
 213 * USB 2.0 spec Section 11.24.2.2
 214 */
 215static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
 216{
 217	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 218		USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
 219		NULL, 0, 1000);
 220}
 221
 222/*
 223 * USB 2.0 spec Section 11.24.2.13
 224 */
 225static int set_port_feature(struct usb_device *hdev, int port1, int feature)
 226{
 227	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 228		USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
 229		NULL, 0, 1000);
 230}
 231
 232/*
 233 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
 234 * for info about using port indicators
 235 */
 236static void set_port_led(
 237	struct usb_hub *hub,
 238	int port1,
 239	int selector
 240)
 241{
 242	int status = set_port_feature(hub->hdev, (selector << 8) | port1,
 243			USB_PORT_FEAT_INDICATOR);
 244	if (status < 0)
 245		dev_dbg (hub->intfdev,
 246			"port %d indicator %s status %d\n",
 247			port1,
 248			({ char *s; switch (selector) {
 249			case HUB_LED_AMBER: s = "amber"; break;
 250			case HUB_LED_GREEN: s = "green"; break;
 251			case HUB_LED_OFF: s = "off"; break;
 252			case HUB_LED_AUTO: s = "auto"; break;
 253			default: s = "??"; break;
 254			}; s; }),
 255			status);
 256}
 257
 258#define	LED_CYCLE_PERIOD	((2*HZ)/3)
 259
 260static void led_work (struct work_struct *work)
 261{
 262	struct usb_hub		*hub =
 263		container_of(work, struct usb_hub, leds.work);
 264	struct usb_device	*hdev = hub->hdev;
 265	unsigned		i;
 266	unsigned		changed = 0;
 267	int			cursor = -1;
 268
 269	if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
 270		return;
 271
 272	for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
 273		unsigned	selector, mode;
 274
 275		/* 30%-50% duty cycle */
 276
 277		switch (hub->indicator[i]) {
 278		/* cycle marker */
 279		case INDICATOR_CYCLE:
 280			cursor = i;
 281			selector = HUB_LED_AUTO;
 282			mode = INDICATOR_AUTO;
 283			break;
 284		/* blinking green = sw attention */
 285		case INDICATOR_GREEN_BLINK:
 286			selector = HUB_LED_GREEN;
 287			mode = INDICATOR_GREEN_BLINK_OFF;
 288			break;
 289		case INDICATOR_GREEN_BLINK_OFF:
 290			selector = HUB_LED_OFF;
 291			mode = INDICATOR_GREEN_BLINK;
 292			break;
 293		/* blinking amber = hw attention */
 294		case INDICATOR_AMBER_BLINK:
 295			selector = HUB_LED_AMBER;
 296			mode = INDICATOR_AMBER_BLINK_OFF;
 297			break;
 298		case INDICATOR_AMBER_BLINK_OFF:
 299			selector = HUB_LED_OFF;
 300			mode = INDICATOR_AMBER_BLINK;
 301			break;
 302		/* blink green/amber = reserved */
 303		case INDICATOR_ALT_BLINK:
 304			selector = HUB_LED_GREEN;
 305			mode = INDICATOR_ALT_BLINK_OFF;
 306			break;
 307		case INDICATOR_ALT_BLINK_OFF:
 308			selector = HUB_LED_AMBER;
 309			mode = INDICATOR_ALT_BLINK;
 310			break;
 311		default:
 312			continue;
 313		}
 314		if (selector != HUB_LED_AUTO)
 315			changed = 1;
 316		set_port_led(hub, i + 1, selector);
 317		hub->indicator[i] = mode;
 318	}
 319	if (!changed && blinkenlights) {
 320		cursor++;
 321		cursor %= hub->descriptor->bNbrPorts;
 322		set_port_led(hub, cursor + 1, HUB_LED_GREEN);
 323		hub->indicator[cursor] = INDICATOR_CYCLE;
 324		changed++;
 325	}
 326	if (changed)
 327		schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 328}
 329
 330/* use a short timeout for hub/port status fetches */
 331#define	USB_STS_TIMEOUT		1000
 332#define	USB_STS_RETRIES		5
 333
 334/*
 335 * USB 2.0 spec Section 11.24.2.6
 336 */
 337static int get_hub_status(struct usb_device *hdev,
 338		struct usb_hub_status *data)
 339{
 340	int i, status = -ETIMEDOUT;
 341
 342	for (i = 0; i < USB_STS_RETRIES &&
 343			(status == -ETIMEDOUT || status == -EPIPE); i++) {
 344		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 345			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
 346			data, sizeof(*data), USB_STS_TIMEOUT);
 347	}
 348	return status;
 349}
 350
 351/*
 352 * USB 2.0 spec Section 11.24.2.7
 353 */
 354static int get_port_status(struct usb_device *hdev, int port1,
 355		struct usb_port_status *data)
 356{
 357	int i, status = -ETIMEDOUT;
 358
 359	for (i = 0; i < USB_STS_RETRIES &&
 360			(status == -ETIMEDOUT || status == -EPIPE); i++) {
 361		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 362			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
 363			data, sizeof(*data), USB_STS_TIMEOUT);
 364	}
 365	return status;
 366}
 367
 368static int hub_port_status(struct usb_hub *hub, int port1,
 369		u16 *status, u16 *change)
 370{
 371	int ret;
 372
 373	mutex_lock(&hub->status_mutex);
 374	ret = get_port_status(hub->hdev, port1, &hub->status->port);
 375	if (ret < 4) {
 376		dev_err(hub->intfdev,
 377			"%s failed (err = %d)\n", __func__, ret);
 378		if (ret >= 0)
 379			ret = -EIO;
 380	} else {
 381		*status = le16_to_cpu(hub->status->port.wPortStatus);
 382		*change = le16_to_cpu(hub->status->port.wPortChange);
 383
 384		ret = 0;
 385	}
 386	mutex_unlock(&hub->status_mutex);
 387	return ret;
 388}
 389
 390static void kick_khubd(struct usb_hub *hub)
 391{
 392	unsigned long	flags;
 393
 394	spin_lock_irqsave(&hub_event_lock, flags);
 395	if (!hub->disconnected && list_empty(&hub->event_list)) {
 396		list_add_tail(&hub->event_list, &hub_event_list);
 397
 398		/* Suppress autosuspend until khubd runs */
 399		usb_autopm_get_interface_no_resume(
 400				to_usb_interface(hub->intfdev));
 401		wake_up(&khubd_wait);
 402	}
 403	spin_unlock_irqrestore(&hub_event_lock, flags);
 404}
 405
 406void usb_kick_khubd(struct usb_device *hdev)
 407{
 408	struct usb_hub *hub = hdev_to_hub(hdev);
 409
 410	if (hub)
 411		kick_khubd(hub);
 412}
 413
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 414
 415/* completion function, fires on port status changes and various faults */
 416static void hub_irq(struct urb *urb)
 417{
 418	struct usb_hub *hub = urb->context;
 419	int status = urb->status;
 420	unsigned i;
 421	unsigned long bits;
 422
 423	switch (status) {
 424	case -ENOENT:		/* synchronous unlink */
 425	case -ECONNRESET:	/* async unlink */
 426	case -ESHUTDOWN:	/* hardware going away */
 427		return;
 428
 429	default:		/* presumably an error */
 430		/* Cause a hub reset after 10 consecutive errors */
 431		dev_dbg (hub->intfdev, "transfer --> %d\n", status);
 432		if ((++hub->nerrors < 10) || hub->error)
 433			goto resubmit;
 434		hub->error = status;
 435		/* FALL THROUGH */
 436
 437	/* let khubd handle things */
 438	case 0:			/* we got data:  port status changed */
 439		bits = 0;
 440		for (i = 0; i < urb->actual_length; ++i)
 441			bits |= ((unsigned long) ((*hub->buffer)[i]))
 442					<< (i*8);
 443		hub->event_bits[0] = bits;
 444		break;
 445	}
 446
 447	hub->nerrors = 0;
 448
 449	/* Something happened, let khubd figure it out */
 450	kick_khubd(hub);
 451
 452resubmit:
 453	if (hub->quiescing)
 454		return;
 455
 456	if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
 457			&& status != -ENODEV && status != -EPERM)
 458		dev_err (hub->intfdev, "resubmit --> %d\n", status);
 459}
 460
 461/* USB 2.0 spec Section 11.24.2.3 */
 462static inline int
 463hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
 464{
 465	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 466			       HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
 467			       tt, NULL, 0, 1000);
 468}
 469
 470/*
 471 * enumeration blocks khubd for a long time. we use keventd instead, since
 472 * long blocking there is the exception, not the rule.  accordingly, HCDs
 473 * talking to TTs must queue control transfers (not just bulk and iso), so
 474 * both can talk to the same hub concurrently.
 475 */
 476static void hub_tt_work(struct work_struct *work)
 477{
 478	struct usb_hub		*hub =
 479		container_of(work, struct usb_hub, tt.clear_work);
 480	unsigned long		flags;
 481	int			limit = 100;
 482
 483	spin_lock_irqsave (&hub->tt.lock, flags);
 484	while (--limit && !list_empty (&hub->tt.clear_list)) {
 485		struct list_head	*next;
 486		struct usb_tt_clear	*clear;
 487		struct usb_device	*hdev = hub->hdev;
 488		const struct hc_driver	*drv;
 489		int			status;
 490
 491		next = hub->tt.clear_list.next;
 492		clear = list_entry (next, struct usb_tt_clear, clear_list);
 493		list_del (&clear->clear_list);
 494
 495		/* drop lock so HCD can concurrently report other TT errors */
 496		spin_unlock_irqrestore (&hub->tt.lock, flags);
 497		status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
 498		if (status)
 499			dev_err (&hdev->dev,
 500				"clear tt %d (%04x) error %d\n",
 501				clear->tt, clear->devinfo, status);
 502
 503		/* Tell the HCD, even if the operation failed */
 504		drv = clear->hcd->driver;
 505		if (drv->clear_tt_buffer_complete)
 506			(drv->clear_tt_buffer_complete)(clear->hcd, clear->ep);
 507
 508		kfree(clear);
 509		spin_lock_irqsave(&hub->tt.lock, flags);
 510	}
 511	spin_unlock_irqrestore (&hub->tt.lock, flags);
 512}
 513
 514/**
 515 * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
 516 * @urb: an URB associated with the failed or incomplete split transaction
 517 *
 518 * High speed HCDs use this to tell the hub driver that some split control or
 519 * bulk transaction failed in a way that requires clearing internal state of
 520 * a transaction translator.  This is normally detected (and reported) from
 521 * interrupt context.
 522 *
 523 * It may not be possible for that hub to handle additional full (or low)
 524 * speed transactions until that state is fully cleared out.
 525 */
 526int usb_hub_clear_tt_buffer(struct urb *urb)
 527{
 528	struct usb_device	*udev = urb->dev;
 529	int			pipe = urb->pipe;
 530	struct usb_tt		*tt = udev->tt;
 531	unsigned long		flags;
 532	struct usb_tt_clear	*clear;
 533
 534	/* we've got to cope with an arbitrary number of pending TT clears,
 535	 * since each TT has "at least two" buffers that can need it (and
 536	 * there can be many TTs per hub).  even if they're uncommon.
 537	 */
 538	if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) {
 539		dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
 540		/* FIXME recover somehow ... RESET_TT? */
 541		return -ENOMEM;
 542	}
 543
 544	/* info that CLEAR_TT_BUFFER needs */
 545	clear->tt = tt->multi ? udev->ttport : 1;
 546	clear->devinfo = usb_pipeendpoint (pipe);
 547	clear->devinfo |= udev->devnum << 4;
 548	clear->devinfo |= usb_pipecontrol (pipe)
 549			? (USB_ENDPOINT_XFER_CONTROL << 11)
 550			: (USB_ENDPOINT_XFER_BULK << 11);
 551	if (usb_pipein (pipe))
 552		clear->devinfo |= 1 << 15;
 553
 554	/* info for completion callback */
 555	clear->hcd = bus_to_hcd(udev->bus);
 556	clear->ep = urb->ep;
 557
 558	/* tell keventd to clear state for this TT */
 559	spin_lock_irqsave (&tt->lock, flags);
 560	list_add_tail (&clear->clear_list, &tt->clear_list);
 561	schedule_work(&tt->clear_work);
 562	spin_unlock_irqrestore (&tt->lock, flags);
 563	return 0;
 564}
 565EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer);
 566
 567/* If do_delay is false, return the number of milliseconds the caller
 568 * needs to delay.
 569 */
 570static unsigned hub_power_on(struct usb_hub *hub, bool do_delay)
 571{
 572	int port1;
 573	unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
 574	unsigned delay;
 575	u16 wHubCharacteristics =
 576			le16_to_cpu(hub->descriptor->wHubCharacteristics);
 577
 578	/* Enable power on each port.  Some hubs have reserved values
 579	 * of LPSM (> 2) in their descriptors, even though they are
 580	 * USB 2.0 hubs.  Some hubs do not implement port-power switching
 581	 * but only emulate it.  In all cases, the ports won't work
 582	 * unless we send these messages to the hub.
 583	 */
 584	if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
 585		dev_dbg(hub->intfdev, "enabling power on all ports\n");
 586	else
 587		dev_dbg(hub->intfdev, "trying to enable port power on "
 588				"non-switchable hub\n");
 589	for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
 590		set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
 591
 592	/* Wait at least 100 msec for power to become stable */
 593	delay = max(pgood_delay, (unsigned) 100);
 594	if (do_delay)
 595		msleep(delay);
 596	return delay;
 597}
 598
 599static int hub_hub_status(struct usb_hub *hub,
 600		u16 *status, u16 *change)
 601{
 602	int ret;
 603
 604	mutex_lock(&hub->status_mutex);
 605	ret = get_hub_status(hub->hdev, &hub->status->hub);
 606	if (ret < 0)
 607		dev_err (hub->intfdev,
 608			"%s failed (err = %d)\n", __func__, ret);
 609	else {
 610		*status = le16_to_cpu(hub->status->hub.wHubStatus);
 611		*change = le16_to_cpu(hub->status->hub.wHubChange); 
 612		ret = 0;
 613	}
 614	mutex_unlock(&hub->status_mutex);
 615	return ret;
 616}
 617
 618static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
 619{
 620	struct usb_device *hdev = hub->hdev;
 621	int ret = 0;
 622
 623	if (hdev->children[port1-1] && set_state)
 624		usb_set_device_state(hdev->children[port1-1],
 625				USB_STATE_NOTATTACHED);
 626	if (!hub->error && !hub_is_superspeed(hub->hdev))
 627		ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
 628	if (ret)
 629		dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
 630				port1, ret);
 631	return ret;
 632}
 633
 634/*
 635 * Disable a port and mark a logical connect-change event, so that some
 636 * time later khubd will disconnect() any existing usb_device on the port
 637 * and will re-enumerate if there actually is a device attached.
 638 */
 639static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
 640{
 641	dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
 642	hub_port_disable(hub, port1, 1);
 643
 644	/* FIXME let caller ask to power down the port:
 645	 *  - some devices won't enumerate without a VBUS power cycle
 646	 *  - SRP saves power that way
 647	 *  - ... new call, TBD ...
 648	 * That's easy if this hub can switch power per-port, and
 649	 * khubd reactivates the port later (timer, SRP, etc).
 650	 * Powerdown must be optional, because of reset/DFU.
 651	 */
 652
 653	set_bit(port1, hub->change_bits);
 654 	kick_khubd(hub);
 655}
 656
 657/**
 658 * usb_remove_device - disable a device's port on its parent hub
 659 * @udev: device to be disabled and removed
 660 * Context: @udev locked, must be able to sleep.
 661 *
 662 * After @udev's port has been disabled, khubd is notified and it will
 663 * see that the device has been disconnected.  When the device is
 664 * physically unplugged and something is plugged in, the events will
 665 * be received and processed normally.
 666 */
 667int usb_remove_device(struct usb_device *udev)
 668{
 669	struct usb_hub *hub;
 670	struct usb_interface *intf;
 671
 672	if (!udev->parent)	/* Can't remove a root hub */
 673		return -EINVAL;
 674	hub = hdev_to_hub(udev->parent);
 675	intf = to_usb_interface(hub->intfdev);
 676
 677	usb_autopm_get_interface(intf);
 678	set_bit(udev->portnum, hub->removed_bits);
 679	hub_port_logical_disconnect(hub, udev->portnum);
 680	usb_autopm_put_interface(intf);
 681	return 0;
 682}
 683
 684enum hub_activation_type {
 685	HUB_INIT, HUB_INIT2, HUB_INIT3,		/* INITs must come first */
 686	HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
 687};
 688
 689static void hub_init_func2(struct work_struct *ws);
 690static void hub_init_func3(struct work_struct *ws);
 691
 692static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
 693{
 694	struct usb_device *hdev = hub->hdev;
 695	struct usb_hcd *hcd;
 696	int ret;
 697	int port1;
 698	int status;
 699	bool need_debounce_delay = false;
 700	unsigned delay;
 701
 702	/* Continue a partial initialization */
 703	if (type == HUB_INIT2)
 704		goto init2;
 705	if (type == HUB_INIT3)
 706		goto init3;
 707
 708	/* After a resume, port power should still be on.
 
 
 
 
 
 
 
 709	 * For any other type of activation, turn it on.
 710	 */
 711	if (type != HUB_RESUME) {
 
 
 
 
 
 
 
 
 
 712
 713		/* Speed up system boot by using a delayed_work for the
 714		 * hub's initial power-up delays.  This is pretty awkward
 715		 * and the implementation looks like a home-brewed sort of
 716		 * setjmp/longjmp, but it saves at least 100 ms for each
 717		 * root hub (assuming usbcore is compiled into the kernel
 718		 * rather than as a module).  It adds up.
 719		 *
 720		 * This can't be done for HUB_RESUME or HUB_RESET_RESUME
 721		 * because for those activation types the ports have to be
 722		 * operational when we return.  In theory this could be done
 723		 * for HUB_POST_RESET, but it's easier not to.
 724		 */
 725		if (type == HUB_INIT) {
 726			delay = hub_power_on(hub, false);
 727			PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func2);
 728			schedule_delayed_work(&hub->init_work,
 729					msecs_to_jiffies(delay));
 730
 731			/* Suppress autosuspend until init is done */
 732			usb_autopm_get_interface_no_resume(
 733					to_usb_interface(hub->intfdev));
 734			return;		/* Continues at init2: below */
 735		} else if (type == HUB_RESET_RESUME) {
 736			/* The internal host controller state for the hub device
 737			 * may be gone after a host power loss on system resume.
 738			 * Update the device's info so the HW knows it's a hub.
 739			 */
 740			hcd = bus_to_hcd(hdev->bus);
 741			if (hcd->driver->update_hub_device) {
 742				ret = hcd->driver->update_hub_device(hcd, hdev,
 743						&hub->tt, GFP_NOIO);
 744				if (ret < 0) {
 745					dev_err(hub->intfdev, "Host not "
 746							"accepting hub info "
 747							"update.\n");
 748					dev_err(hub->intfdev, "LS/FS devices "
 749							"and hubs may not work "
 750							"under this hub\n.");
 751				}
 752			}
 753			hub_power_on(hub, true);
 754		} else {
 755			hub_power_on(hub, true);
 756		}
 757	}
 758 init2:
 759
 760	/* Check each port and set hub->change_bits to let khubd know
 761	 * which ports need attention.
 762	 */
 763	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
 764		struct usb_device *udev = hdev->children[port1-1];
 765		u16 portstatus, portchange;
 766
 767		portstatus = portchange = 0;
 768		status = hub_port_status(hub, port1, &portstatus, &portchange);
 769		if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
 770			dev_dbg(hub->intfdev,
 771					"port %d: status %04x change %04x\n",
 772					port1, portstatus, portchange);
 773
 774		/* After anything other than HUB_RESUME (i.e., initialization
 775		 * or any sort of reset), every port should be disabled.
 776		 * Unconnected ports should likewise be disabled (paranoia),
 777		 * and so should ports for which we have no usb_device.
 778		 */
 779		if ((portstatus & USB_PORT_STAT_ENABLE) && (
 780				type != HUB_RESUME ||
 781				!(portstatus & USB_PORT_STAT_CONNECTION) ||
 782				!udev ||
 783				udev->state == USB_STATE_NOTATTACHED)) {
 784			/*
 785			 * USB3 protocol ports will automatically transition
 786			 * to Enabled state when detect an USB3.0 device attach.
 787			 * Do not disable USB3 protocol ports.
 788			 */
 789			if (!hub_is_superspeed(hdev)) {
 790				clear_port_feature(hdev, port1,
 791						   USB_PORT_FEAT_ENABLE);
 792				portstatus &= ~USB_PORT_STAT_ENABLE;
 793			} else {
 794				/* Pretend that power was lost for USB3 devs */
 795				portstatus &= ~USB_PORT_STAT_ENABLE;
 796			}
 797		}
 798
 799		/* Clear status-change flags; we'll debounce later */
 800		if (portchange & USB_PORT_STAT_C_CONNECTION) {
 801			need_debounce_delay = true;
 802			clear_port_feature(hub->hdev, port1,
 803					USB_PORT_FEAT_C_CONNECTION);
 804		}
 805		if (portchange & USB_PORT_STAT_C_ENABLE) {
 806			need_debounce_delay = true;
 807			clear_port_feature(hub->hdev, port1,
 808					USB_PORT_FEAT_C_ENABLE);
 809		}
 810		if (portchange & USB_PORT_STAT_C_LINK_STATE) {
 
 811			need_debounce_delay = true;
 812			clear_port_feature(hub->hdev, port1,
 813					USB_PORT_FEAT_C_PORT_LINK_STATE);
 814		}
 815
 816		/* We can forget about a "removed" device when there's a
 817		 * physical disconnect or the connect status changes.
 818		 */
 819		if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
 820				(portchange & USB_PORT_STAT_C_CONNECTION))
 821			clear_bit(port1, hub->removed_bits);
 822
 823		if (!udev || udev->state == USB_STATE_NOTATTACHED) {
 824			/* Tell khubd to disconnect the device or
 825			 * check for a new connection
 826			 */
 827			if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
 828				set_bit(port1, hub->change_bits);
 829
 830		} else if (portstatus & USB_PORT_STAT_ENABLE) {
 
 
 
 831			/* The power session apparently survived the resume.
 832			 * If there was an overcurrent or suspend change
 833			 * (i.e., remote wakeup request), have khubd
 834			 * take care of it.
 
 
 
 835			 */
 836			if (portchange)
 
 837				set_bit(port1, hub->change_bits);
 838
 839		} else if (udev->persist_enabled) {
 840#ifdef CONFIG_PM
 841			udev->reset_resume = 1;
 842#endif
 843			set_bit(port1, hub->change_bits);
 844
 845		} else {
 846			/* The power session is gone; tell khubd */
 847			usb_set_device_state(udev, USB_STATE_NOTATTACHED);
 848			set_bit(port1, hub->change_bits);
 849		}
 850	}
 851
 852	/* If no port-status-change flags were set, we don't need any
 853	 * debouncing.  If flags were set we can try to debounce the
 854	 * ports all at once right now, instead of letting khubd do them
 855	 * one at a time later on.
 856	 *
 857	 * If any port-status changes do occur during this delay, khubd
 858	 * will see them later and handle them normally.
 859	 */
 860	if (need_debounce_delay) {
 861		delay = HUB_DEBOUNCE_STABLE;
 862
 863		/* Don't do a long sleep inside a workqueue routine */
 864		if (type == HUB_INIT2) {
 865			PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func3);
 866			schedule_delayed_work(&hub->init_work,
 867					msecs_to_jiffies(delay));
 868			return;		/* Continues at init3: below */
 869		} else {
 870			msleep(delay);
 871		}
 872	}
 873 init3:
 874	hub->quiescing = 0;
 875
 876	status = usb_submit_urb(hub->urb, GFP_NOIO);
 877	if (status < 0)
 878		dev_err(hub->intfdev, "activate --> %d\n", status);
 879	if (hub->has_indicators && blinkenlights)
 880		schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 881
 882	/* Scan all ports that need attention */
 883	kick_khubd(hub);
 884
 885	/* Allow autosuspend if it was suppressed */
 886	if (type <= HUB_INIT3)
 887		usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
 888}
 889
 890/* Implement the continuations for the delays above */
 891static void hub_init_func2(struct work_struct *ws)
 892{
 893	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
 894
 895	hub_activate(hub, HUB_INIT2);
 896}
 897
 898static void hub_init_func3(struct work_struct *ws)
 899{
 900	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
 901
 902	hub_activate(hub, HUB_INIT3);
 903}
 904
 905enum hub_quiescing_type {
 906	HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
 907};
 908
 909static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
 910{
 911	struct usb_device *hdev = hub->hdev;
 912	int i;
 913
 914	cancel_delayed_work_sync(&hub->init_work);
 915
 916	/* khubd and related activity won't re-trigger */
 917	hub->quiescing = 1;
 918
 919	if (type != HUB_SUSPEND) {
 920		/* Disconnect all the children */
 921		for (i = 0; i < hdev->maxchild; ++i) {
 922			if (hdev->children[i])
 923				usb_disconnect(&hdev->children[i]);
 924		}
 925	}
 926
 927	/* Stop khubd and related activity */
 928	usb_kill_urb(hub->urb);
 929	if (hub->has_indicators)
 930		cancel_delayed_work_sync(&hub->leds);
 931	if (hub->tt.hub)
 932		cancel_work_sync(&hub->tt.clear_work);
 933}
 934
 935/* caller has locked the hub device */
 936static int hub_pre_reset(struct usb_interface *intf)
 937{
 938	struct usb_hub *hub = usb_get_intfdata(intf);
 939
 940	hub_quiesce(hub, HUB_PRE_RESET);
 941	return 0;
 942}
 943
 944/* caller has locked the hub device */
 945static int hub_post_reset(struct usb_interface *intf)
 946{
 947	struct usb_hub *hub = usb_get_intfdata(intf);
 948
 949	hub_activate(hub, HUB_POST_RESET);
 950	return 0;
 951}
 952
 953static int hub_configure(struct usb_hub *hub,
 954	struct usb_endpoint_descriptor *endpoint)
 955{
 956	struct usb_hcd *hcd;
 957	struct usb_device *hdev = hub->hdev;
 958	struct device *hub_dev = hub->intfdev;
 959	u16 hubstatus, hubchange;
 960	u16 wHubCharacteristics;
 961	unsigned int pipe;
 962	int maxp, ret;
 963	char *message = "out of memory";
 964
 965	hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
 966	if (!hub->buffer) {
 967		ret = -ENOMEM;
 968		goto fail;
 969	}
 970
 971	hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
 972	if (!hub->status) {
 973		ret = -ENOMEM;
 974		goto fail;
 975	}
 976	mutex_init(&hub->status_mutex);
 977
 978	hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
 979	if (!hub->descriptor) {
 980		ret = -ENOMEM;
 981		goto fail;
 982	}
 983
 984	if (hub_is_superspeed(hdev) && (hdev->parent != NULL)) {
 985		ret = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 986				HUB_SET_DEPTH, USB_RT_HUB,
 987				hdev->level - 1, 0, NULL, 0,
 988				USB_CTRL_SET_TIMEOUT);
 989
 990		if (ret < 0) {
 991			message = "can't set hub depth";
 992			goto fail;
 993		}
 994	}
 995
 996	/* Request the entire hub descriptor.
 997	 * hub->descriptor can handle USB_MAXCHILDREN ports,
 998	 * but the hub can/will return fewer bytes here.
 999	 */
1000	ret = get_hub_descriptor(hdev, hub->descriptor);
1001	if (ret < 0) {
1002		message = "can't read hub descriptor";
1003		goto fail;
1004	} else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
1005		message = "hub has too many ports!";
1006		ret = -ENODEV;
1007		goto fail;
1008	}
1009
1010	hdev->maxchild = hub->descriptor->bNbrPorts;
1011	dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
1012		(hdev->maxchild == 1) ? "" : "s");
1013
 
 
1014	hub->port_owners = kzalloc(hdev->maxchild * sizeof(void *), GFP_KERNEL);
1015	if (!hub->port_owners) {
1016		ret = -ENOMEM;
1017		goto fail;
1018	}
1019
1020	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
1021
1022	/* FIXME for USB 3.0, skip for now */
1023	if ((wHubCharacteristics & HUB_CHAR_COMPOUND) &&
1024			!(hub_is_superspeed(hdev))) {
1025		int	i;
1026		char	portstr [USB_MAXCHILDREN + 1];
1027
1028		for (i = 0; i < hdev->maxchild; i++)
1029			portstr[i] = hub->descriptor->u.hs.DeviceRemovable
1030				    [((i + 1) / 8)] & (1 << ((i + 1) % 8))
1031				? 'F' : 'R';
1032		portstr[hdev->maxchild] = 0;
1033		dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
1034	} else
1035		dev_dbg(hub_dev, "standalone hub\n");
1036
1037	switch (wHubCharacteristics & HUB_CHAR_LPSM) {
1038		case 0x00:
1039			dev_dbg(hub_dev, "ganged power switching\n");
1040			break;
1041		case 0x01:
1042			dev_dbg(hub_dev, "individual port power switching\n");
1043			break;
1044		case 0x02:
1045		case 0x03:
1046			dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
1047			break;
1048	}
1049
1050	switch (wHubCharacteristics & HUB_CHAR_OCPM) {
1051		case 0x00:
1052			dev_dbg(hub_dev, "global over-current protection\n");
1053			break;
1054		case 0x08:
1055			dev_dbg(hub_dev, "individual port over-current protection\n");
1056			break;
1057		case 0x10:
1058		case 0x18:
1059			dev_dbg(hub_dev, "no over-current protection\n");
1060                        break;
1061	}
1062
1063	spin_lock_init (&hub->tt.lock);
1064	INIT_LIST_HEAD (&hub->tt.clear_list);
1065	INIT_WORK(&hub->tt.clear_work, hub_tt_work);
1066	switch (hdev->descriptor.bDeviceProtocol) {
1067		case 0:
1068			break;
1069		case 1:
1070			dev_dbg(hub_dev, "Single TT\n");
1071			hub->tt.hub = hdev;
1072			break;
1073		case 2:
1074			ret = usb_set_interface(hdev, 0, 1);
1075			if (ret == 0) {
1076				dev_dbg(hub_dev, "TT per port\n");
1077				hub->tt.multi = 1;
1078			} else
1079				dev_err(hub_dev, "Using single TT (err %d)\n",
1080					ret);
1081			hub->tt.hub = hdev;
1082			break;
1083		case 3:
1084			/* USB 3.0 hubs don't have a TT */
1085			break;
1086		default:
1087			dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
1088				hdev->descriptor.bDeviceProtocol);
1089			break;
1090	}
1091
1092	/* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
1093	switch (wHubCharacteristics & HUB_CHAR_TTTT) {
1094		case HUB_TTTT_8_BITS:
1095			if (hdev->descriptor.bDeviceProtocol != 0) {
1096				hub->tt.think_time = 666;
1097				dev_dbg(hub_dev, "TT requires at most %d "
1098						"FS bit times (%d ns)\n",
1099					8, hub->tt.think_time);
1100			}
1101			break;
1102		case HUB_TTTT_16_BITS:
1103			hub->tt.think_time = 666 * 2;
1104			dev_dbg(hub_dev, "TT requires at most %d "
1105					"FS bit times (%d ns)\n",
1106				16, hub->tt.think_time);
1107			break;
1108		case HUB_TTTT_24_BITS:
1109			hub->tt.think_time = 666 * 3;
1110			dev_dbg(hub_dev, "TT requires at most %d "
1111					"FS bit times (%d ns)\n",
1112				24, hub->tt.think_time);
1113			break;
1114		case HUB_TTTT_32_BITS:
1115			hub->tt.think_time = 666 * 4;
1116			dev_dbg(hub_dev, "TT requires at most %d "
1117					"FS bit times (%d ns)\n",
1118				32, hub->tt.think_time);
1119			break;
1120	}
1121
1122	/* probe() zeroes hub->indicator[] */
1123	if (wHubCharacteristics & HUB_CHAR_PORTIND) {
1124		hub->has_indicators = 1;
1125		dev_dbg(hub_dev, "Port indicators are supported\n");
1126	}
1127
1128	dev_dbg(hub_dev, "power on to power good time: %dms\n",
1129		hub->descriptor->bPwrOn2PwrGood * 2);
1130
1131	/* power budgeting mostly matters with bus-powered hubs,
1132	 * and battery-powered root hubs (may provide just 8 mA).
1133	 */
1134	ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
1135	if (ret < 2) {
1136		message = "can't get hub status";
1137		goto fail;
1138	}
1139	le16_to_cpus(&hubstatus);
1140	if (hdev == hdev->bus->root_hub) {
1141		if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
1142			hub->mA_per_port = 500;
1143		else {
1144			hub->mA_per_port = hdev->bus_mA;
1145			hub->limited_power = 1;
1146		}
1147	} else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1148		dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
1149			hub->descriptor->bHubContrCurrent);
1150		hub->limited_power = 1;
1151		if (hdev->maxchild > 0) {
1152			int remaining = hdev->bus_mA -
1153					hub->descriptor->bHubContrCurrent;
1154
1155			if (remaining < hdev->maxchild * 100)
1156				dev_warn(hub_dev,
1157					"insufficient power available "
1158					"to use all downstream ports\n");
1159			hub->mA_per_port = 100;		/* 7.2.1.1 */
1160		}
1161	} else {	/* Self-powered external hub */
1162		/* FIXME: What about battery-powered external hubs that
1163		 * provide less current per port? */
1164		hub->mA_per_port = 500;
1165	}
1166	if (hub->mA_per_port < 500)
1167		dev_dbg(hub_dev, "%umA bus power budget for each child\n",
1168				hub->mA_per_port);
1169
1170	/* Update the HCD's internal representation of this hub before khubd
1171	 * starts getting port status changes for devices under the hub.
1172	 */
1173	hcd = bus_to_hcd(hdev->bus);
1174	if (hcd->driver->update_hub_device) {
1175		ret = hcd->driver->update_hub_device(hcd, hdev,
1176				&hub->tt, GFP_KERNEL);
1177		if (ret < 0) {
1178			message = "can't update HCD hub info";
1179			goto fail;
1180		}
1181	}
1182
1183	ret = hub_hub_status(hub, &hubstatus, &hubchange);
1184	if (ret < 0) {
1185		message = "can't get hub status";
1186		goto fail;
1187	}
1188
1189	/* local power status reports aren't always correct */
1190	if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
1191		dev_dbg(hub_dev, "local power source is %s\n",
1192			(hubstatus & HUB_STATUS_LOCAL_POWER)
1193			? "lost (inactive)" : "good");
1194
1195	if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
1196		dev_dbg(hub_dev, "%sover-current condition exists\n",
1197			(hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
1198
1199	/* set up the interrupt endpoint
1200	 * We use the EP's maxpacket size instead of (PORTS+1+7)/8
1201	 * bytes as USB2.0[11.12.3] says because some hubs are known
1202	 * to send more data (and thus cause overflow). For root hubs,
1203	 * maxpktsize is defined in hcd.c's fake endpoint descriptors
1204	 * to be big enough for at least USB_MAXCHILDREN ports. */
1205	pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
1206	maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
1207
1208	if (maxp > sizeof(*hub->buffer))
1209		maxp = sizeof(*hub->buffer);
1210
1211	hub->urb = usb_alloc_urb(0, GFP_KERNEL);
1212	if (!hub->urb) {
1213		ret = -ENOMEM;
1214		goto fail;
1215	}
1216
1217	usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1218		hub, endpoint->bInterval);
1219
1220	/* maybe cycle the hub leds */
1221	if (hub->has_indicators && blinkenlights)
1222		hub->indicator [0] = INDICATOR_CYCLE;
1223
1224	hub_activate(hub, HUB_INIT);
1225	return 0;
1226
1227fail:
1228	dev_err (hub_dev, "config failed, %s (err %d)\n",
1229			message, ret);
1230	/* hub_disconnect() frees urb and descriptor */
1231	return ret;
1232}
1233
1234static void hub_release(struct kref *kref)
1235{
1236	struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1237
1238	usb_put_intf(to_usb_interface(hub->intfdev));
1239	kfree(hub);
1240}
1241
1242static unsigned highspeed_hubs;
1243
1244static void hub_disconnect(struct usb_interface *intf)
1245{
1246	struct usb_hub *hub = usb_get_intfdata (intf);
 
1247
1248	/* Take the hub off the event list and don't let it be added again */
1249	spin_lock_irq(&hub_event_lock);
1250	if (!list_empty(&hub->event_list)) {
1251		list_del_init(&hub->event_list);
1252		usb_autopm_put_interface_no_suspend(intf);
1253	}
1254	hub->disconnected = 1;
1255	spin_unlock_irq(&hub_event_lock);
1256
1257	/* Disconnect all children and quiesce the hub */
1258	hub->error = 0;
1259	hub_quiesce(hub, HUB_DISCONNECT);
1260
1261	usb_set_intfdata (intf, NULL);
1262	hub->hdev->maxchild = 0;
1263
1264	if (hub->hdev->speed == USB_SPEED_HIGH)
1265		highspeed_hubs--;
1266
1267	usb_free_urb(hub->urb);
 
1268	kfree(hub->port_owners);
1269	kfree(hub->descriptor);
1270	kfree(hub->status);
1271	kfree(hub->buffer);
1272
1273	kref_put(&hub->kref, hub_release);
1274}
1275
1276static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1277{
1278	struct usb_host_interface *desc;
1279	struct usb_endpoint_descriptor *endpoint;
1280	struct usb_device *hdev;
1281	struct usb_hub *hub;
1282
1283	desc = intf->cur_altsetting;
1284	hdev = interface_to_usbdev(intf);
1285
1286	/* Hubs have proper suspend/resume support.  USB 3.0 device suspend is
1287	 * different from USB 2.0/1.1 device suspend, and unfortunately we
1288	 * don't support it yet.  So leave autosuspend disabled for USB 3.0
1289	 * external hubs for now.  Enable autosuspend for USB 3.0 roothubs,
1290	 * since that isn't a "real" hub.
1291	 */
1292	if (!hub_is_superspeed(hdev) || !hdev->parent)
1293		usb_enable_autosuspend(hdev);
1294
1295	if (hdev->level == MAX_TOPO_LEVEL) {
1296		dev_err(&intf->dev,
1297			"Unsupported bus topology: hub nested too deep\n");
1298		return -E2BIG;
1299	}
1300
1301#ifdef	CONFIG_USB_OTG_BLACKLIST_HUB
1302	if (hdev->parent) {
1303		dev_warn(&intf->dev, "ignoring external hub\n");
1304		return -ENODEV;
1305	}
1306#endif
1307
1308	/* Some hubs have a subclass of 1, which AFAICT according to the */
1309	/*  specs is not defined, but it works */
1310	if ((desc->desc.bInterfaceSubClass != 0) &&
1311	    (desc->desc.bInterfaceSubClass != 1)) {
1312descriptor_error:
1313		dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
1314		return -EIO;
1315	}
1316
1317	/* Multiple endpoints? What kind of mutant ninja-hub is this? */
1318	if (desc->desc.bNumEndpoints != 1)
1319		goto descriptor_error;
1320
1321	endpoint = &desc->endpoint[0].desc;
1322
1323	/* If it's not an interrupt in endpoint, we'd better punt! */
1324	if (!usb_endpoint_is_int_in(endpoint))
1325		goto descriptor_error;
1326
1327	/* We found a hub */
1328	dev_info (&intf->dev, "USB hub found\n");
1329
1330	hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1331	if (!hub) {
1332		dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
1333		return -ENOMEM;
1334	}
1335
1336	kref_init(&hub->kref);
1337	INIT_LIST_HEAD(&hub->event_list);
1338	hub->intfdev = &intf->dev;
1339	hub->hdev = hdev;
1340	INIT_DELAYED_WORK(&hub->leds, led_work);
1341	INIT_DELAYED_WORK(&hub->init_work, NULL);
1342	usb_get_intf(intf);
1343
1344	usb_set_intfdata (intf, hub);
1345	intf->needs_remote_wakeup = 1;
1346
1347	if (hdev->speed == USB_SPEED_HIGH)
1348		highspeed_hubs++;
1349
1350	if (hub_configure(hub, endpoint) >= 0)
1351		return 0;
1352
1353	hub_disconnect (intf);
1354	return -ENODEV;
1355}
1356
1357/* No BKL needed */
1358static int
1359hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1360{
1361	struct usb_device *hdev = interface_to_usbdev (intf);
1362
1363	/* assert ifno == 0 (part of hub spec) */
1364	switch (code) {
1365	case USBDEVFS_HUB_PORTINFO: {
1366		struct usbdevfs_hub_portinfo *info = user_data;
1367		int i;
1368
1369		spin_lock_irq(&device_state_lock);
1370		if (hdev->devnum <= 0)
1371			info->nports = 0;
1372		else {
1373			info->nports = hdev->maxchild;
1374			for (i = 0; i < info->nports; i++) {
1375				if (hdev->children[i] == NULL)
1376					info->port[i] = 0;
1377				else
1378					info->port[i] =
1379						hdev->children[i]->devnum;
1380			}
1381		}
1382		spin_unlock_irq(&device_state_lock);
1383
1384		return info->nports + 1;
1385		}
1386
1387	default:
1388		return -ENOSYS;
1389	}
1390}
1391
1392/*
1393 * Allow user programs to claim ports on a hub.  When a device is attached
1394 * to one of these "claimed" ports, the program will "own" the device.
1395 */
1396static int find_port_owner(struct usb_device *hdev, unsigned port1,
1397		void ***ppowner)
1398{
1399	if (hdev->state == USB_STATE_NOTATTACHED)
1400		return -ENODEV;
1401	if (port1 == 0 || port1 > hdev->maxchild)
1402		return -EINVAL;
1403
1404	/* This assumes that devices not managed by the hub driver
1405	 * will always have maxchild equal to 0.
1406	 */
1407	*ppowner = &(hdev_to_hub(hdev)->port_owners[port1 - 1]);
1408	return 0;
1409}
1410
1411/* In the following three functions, the caller must hold hdev's lock */
1412int usb_hub_claim_port(struct usb_device *hdev, unsigned port1, void *owner)
1413{
1414	int rc;
1415	void **powner;
1416
1417	rc = find_port_owner(hdev, port1, &powner);
1418	if (rc)
1419		return rc;
1420	if (*powner)
1421		return -EBUSY;
1422	*powner = owner;
1423	return rc;
1424}
1425
1426int usb_hub_release_port(struct usb_device *hdev, unsigned port1, void *owner)
1427{
1428	int rc;
1429	void **powner;
1430
1431	rc = find_port_owner(hdev, port1, &powner);
1432	if (rc)
1433		return rc;
1434	if (*powner != owner)
1435		return -ENOENT;
1436	*powner = NULL;
1437	return rc;
1438}
1439
1440void usb_hub_release_all_ports(struct usb_device *hdev, void *owner)
1441{
1442	int n;
1443	void **powner;
1444
1445	n = find_port_owner(hdev, 1, &powner);
1446	if (n == 0) {
1447		for (; n < hdev->maxchild; (++n, ++powner)) {
1448			if (*powner == owner)
1449				*powner = NULL;
1450		}
1451	}
1452}
1453
1454/* The caller must hold udev's lock */
1455bool usb_device_is_owned(struct usb_device *udev)
1456{
1457	struct usb_hub *hub;
1458
1459	if (udev->state == USB_STATE_NOTATTACHED || !udev->parent)
1460		return false;
1461	hub = hdev_to_hub(udev->parent);
1462	return !!hub->port_owners[udev->portnum - 1];
1463}
1464
1465
1466static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1467{
1468	int i;
1469
1470	for (i = 0; i < udev->maxchild; ++i) {
1471		if (udev->children[i])
1472			recursively_mark_NOTATTACHED(udev->children[i]);
1473	}
1474	if (udev->state == USB_STATE_SUSPENDED)
1475		udev->active_duration -= jiffies;
1476	udev->state = USB_STATE_NOTATTACHED;
1477}
1478
1479/**
1480 * usb_set_device_state - change a device's current state (usbcore, hcds)
1481 * @udev: pointer to device whose state should be changed
1482 * @new_state: new state value to be stored
1483 *
1484 * udev->state is _not_ fully protected by the device lock.  Although
1485 * most transitions are made only while holding the lock, the state can
1486 * can change to USB_STATE_NOTATTACHED at almost any time.  This
1487 * is so that devices can be marked as disconnected as soon as possible,
1488 * without having to wait for any semaphores to be released.  As a result,
1489 * all changes to any device's state must be protected by the
1490 * device_state_lock spinlock.
1491 *
1492 * Once a device has been added to the device tree, all changes to its state
1493 * should be made using this routine.  The state should _not_ be set directly.
1494 *
1495 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1496 * Otherwise udev->state is set to new_state, and if new_state is
1497 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1498 * to USB_STATE_NOTATTACHED.
1499 */
1500void usb_set_device_state(struct usb_device *udev,
1501		enum usb_device_state new_state)
1502{
1503	unsigned long flags;
1504	int wakeup = -1;
1505
1506	spin_lock_irqsave(&device_state_lock, flags);
1507	if (udev->state == USB_STATE_NOTATTACHED)
1508		;	/* do nothing */
1509	else if (new_state != USB_STATE_NOTATTACHED) {
1510
1511		/* root hub wakeup capabilities are managed out-of-band
1512		 * and may involve silicon errata ... ignore them here.
1513		 */
1514		if (udev->parent) {
1515			if (udev->state == USB_STATE_SUSPENDED
1516					|| new_state == USB_STATE_SUSPENDED)
1517				;	/* No change to wakeup settings */
1518			else if (new_state == USB_STATE_CONFIGURED)
1519				wakeup = udev->actconfig->desc.bmAttributes
1520					 & USB_CONFIG_ATT_WAKEUP;
1521			else
1522				wakeup = 0;
1523		}
1524		if (udev->state == USB_STATE_SUSPENDED &&
1525			new_state != USB_STATE_SUSPENDED)
1526			udev->active_duration -= jiffies;
1527		else if (new_state == USB_STATE_SUSPENDED &&
1528				udev->state != USB_STATE_SUSPENDED)
1529			udev->active_duration += jiffies;
1530		udev->state = new_state;
1531	} else
1532		recursively_mark_NOTATTACHED(udev);
1533	spin_unlock_irqrestore(&device_state_lock, flags);
1534	if (wakeup >= 0)
1535		device_set_wakeup_capable(&udev->dev, wakeup);
1536}
1537EXPORT_SYMBOL_GPL(usb_set_device_state);
1538
1539/*
1540 * Choose a device number.
1541 *
1542 * Device numbers are used as filenames in usbfs.  On USB-1.1 and
1543 * USB-2.0 buses they are also used as device addresses, however on
1544 * USB-3.0 buses the address is assigned by the controller hardware
1545 * and it usually is not the same as the device number.
1546 *
1547 * WUSB devices are simple: they have no hubs behind, so the mapping
1548 * device <-> virtual port number becomes 1:1. Why? to simplify the
1549 * life of the device connection logic in
1550 * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
1551 * handshake we need to assign a temporary address in the unauthorized
1552 * space. For simplicity we use the first virtual port number found to
1553 * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
1554 * and that becomes it's address [X < 128] or its unauthorized address
1555 * [X | 0x80].
1556 *
1557 * We add 1 as an offset to the one-based USB-stack port number
1558 * (zero-based wusb virtual port index) for two reasons: (a) dev addr
1559 * 0 is reserved by USB for default address; (b) Linux's USB stack
1560 * uses always #1 for the root hub of the controller. So USB stack's
1561 * port #1, which is wusb virtual-port #0 has address #2.
1562 *
1563 * Devices connected under xHCI are not as simple.  The host controller
1564 * supports virtualization, so the hardware assigns device addresses and
1565 * the HCD must setup data structures before issuing a set address
1566 * command to the hardware.
1567 */
1568static void choose_devnum(struct usb_device *udev)
1569{
1570	int		devnum;
1571	struct usb_bus	*bus = udev->bus;
1572
1573	/* If khubd ever becomes multithreaded, this will need a lock */
1574	if (udev->wusb) {
1575		devnum = udev->portnum + 1;
1576		BUG_ON(test_bit(devnum, bus->devmap.devicemap));
1577	} else {
1578		/* Try to allocate the next devnum beginning at
1579		 * bus->devnum_next. */
1580		devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1581					    bus->devnum_next);
1582		if (devnum >= 128)
1583			devnum = find_next_zero_bit(bus->devmap.devicemap,
1584						    128, 1);
1585		bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1586	}
1587	if (devnum < 128) {
1588		set_bit(devnum, bus->devmap.devicemap);
1589		udev->devnum = devnum;
1590	}
1591}
1592
1593static void release_devnum(struct usb_device *udev)
1594{
1595	if (udev->devnum > 0) {
1596		clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1597		udev->devnum = -1;
1598	}
1599}
1600
1601static void update_devnum(struct usb_device *udev, int devnum)
1602{
1603	/* The address for a WUSB device is managed by wusbcore. */
1604	if (!udev->wusb)
1605		udev->devnum = devnum;
1606}
1607
1608static void hub_free_dev(struct usb_device *udev)
1609{
1610	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1611
1612	/* Root hubs aren't real devices, so don't free HCD resources */
1613	if (hcd->driver->free_dev && udev->parent)
1614		hcd->driver->free_dev(hcd, udev);
1615}
1616
1617/**
1618 * usb_disconnect - disconnect a device (usbcore-internal)
1619 * @pdev: pointer to device being disconnected
1620 * Context: !in_interrupt ()
1621 *
1622 * Something got disconnected. Get rid of it and all of its children.
1623 *
1624 * If *pdev is a normal device then the parent hub must already be locked.
1625 * If *pdev is a root hub then this routine will acquire the
1626 * usb_bus_list_lock on behalf of the caller.
1627 *
1628 * Only hub drivers (including virtual root hub drivers for host
1629 * controllers) should ever call this.
1630 *
1631 * This call is synchronous, and may not be used in an interrupt context.
1632 */
1633void usb_disconnect(struct usb_device **pdev)
1634{
1635	struct usb_device	*udev = *pdev;
1636	int			i;
1637	struct usb_hcd		*hcd = bus_to_hcd(udev->bus);
1638
1639	if (!udev) {
1640		pr_debug ("%s nodev\n", __func__);
1641		return;
1642	}
1643
1644	/* mark the device as inactive, so any further urb submissions for
1645	 * this device (and any of its children) will fail immediately.
1646	 * this quiesces everything except pending urbs.
1647	 */
1648	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1649	dev_info(&udev->dev, "USB disconnect, device number %d\n",
1650			udev->devnum);
1651
1652	usb_lock_device(udev);
1653
1654	/* Free up all the children before we remove this device */
1655	for (i = 0; i < USB_MAXCHILDREN; i++) {
1656		if (udev->children[i])
1657			usb_disconnect(&udev->children[i]);
1658	}
1659
1660	/* deallocate hcd/hardware state ... nuking all pending urbs and
1661	 * cleaning up all state associated with the current configuration
1662	 * so that the hardware is now fully quiesced.
1663	 */
1664	dev_dbg (&udev->dev, "unregistering device\n");
1665	mutex_lock(hcd->bandwidth_mutex);
1666	usb_disable_device(udev, 0);
1667	mutex_unlock(hcd->bandwidth_mutex);
1668	usb_hcd_synchronize_unlinks(udev);
1669
1670	usb_remove_ep_devs(&udev->ep0);
1671	usb_unlock_device(udev);
1672
1673	/* Unregister the device.  The device driver is responsible
1674	 * for de-configuring the device and invoking the remove-device
1675	 * notifier chain (used by usbfs and possibly others).
1676	 */
1677	device_del(&udev->dev);
1678
1679	/* Free the device number and delete the parent's children[]
1680	 * (or root_hub) pointer.
1681	 */
1682	release_devnum(udev);
1683
1684	/* Avoid races with recursively_mark_NOTATTACHED() */
1685	spin_lock_irq(&device_state_lock);
1686	*pdev = NULL;
1687	spin_unlock_irq(&device_state_lock);
1688
1689	hub_free_dev(udev);
1690
1691	put_device(&udev->dev);
1692}
1693
1694#ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
1695static void show_string(struct usb_device *udev, char *id, char *string)
1696{
1697	if (!string)
1698		return;
1699	dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1700}
1701
1702static void announce_device(struct usb_device *udev)
1703{
1704	dev_info(&udev->dev, "New USB device found, idVendor=%04x, idProduct=%04x\n",
1705		le16_to_cpu(udev->descriptor.idVendor),
1706		le16_to_cpu(udev->descriptor.idProduct));
1707	dev_info(&udev->dev,
1708		"New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
1709		udev->descriptor.iManufacturer,
1710		udev->descriptor.iProduct,
1711		udev->descriptor.iSerialNumber);
1712	show_string(udev, "Product", udev->product);
1713	show_string(udev, "Manufacturer", udev->manufacturer);
1714	show_string(udev, "SerialNumber", udev->serial);
1715}
1716#else
1717static inline void announce_device(struct usb_device *udev) { }
1718#endif
1719
1720#ifdef	CONFIG_USB_OTG
1721#include "otg_whitelist.h"
1722#endif
1723
1724/**
1725 * usb_enumerate_device_otg - FIXME (usbcore-internal)
1726 * @udev: newly addressed device (in ADDRESS state)
1727 *
1728 * Finish enumeration for On-The-Go devices
1729 */
1730static int usb_enumerate_device_otg(struct usb_device *udev)
1731{
1732	int err = 0;
1733
1734#ifdef	CONFIG_USB_OTG
1735	/*
1736	 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1737	 * to wake us after we've powered off VBUS; and HNP, switching roles
1738	 * "host" to "peripheral".  The OTG descriptor helps figure this out.
1739	 */
1740	if (!udev->bus->is_b_host
1741			&& udev->config
1742			&& udev->parent == udev->bus->root_hub) {
1743		struct usb_otg_descriptor	*desc = NULL;
1744		struct usb_bus			*bus = udev->bus;
1745
1746		/* descriptor may appear anywhere in config */
1747		if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1748					le16_to_cpu(udev->config[0].desc.wTotalLength),
1749					USB_DT_OTG, (void **) &desc) == 0) {
1750			if (desc->bmAttributes & USB_OTG_HNP) {
1751				unsigned		port1 = udev->portnum;
1752
1753				dev_info(&udev->dev,
1754					"Dual-Role OTG device on %sHNP port\n",
1755					(port1 == bus->otg_port)
1756						? "" : "non-");
1757
1758				/* enable HNP before suspend, it's simpler */
1759				if (port1 == bus->otg_port)
1760					bus->b_hnp_enable = 1;
1761				err = usb_control_msg(udev,
1762					usb_sndctrlpipe(udev, 0),
1763					USB_REQ_SET_FEATURE, 0,
1764					bus->b_hnp_enable
1765						? USB_DEVICE_B_HNP_ENABLE
1766						: USB_DEVICE_A_ALT_HNP_SUPPORT,
1767					0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1768				if (err < 0) {
1769					/* OTG MESSAGE: report errors here,
1770					 * customize to match your product.
1771					 */
1772					dev_info(&udev->dev,
1773						"can't set HNP mode: %d\n",
1774						err);
1775					bus->b_hnp_enable = 0;
1776				}
1777			}
1778		}
1779	}
1780
1781	if (!is_targeted(udev)) {
1782
1783		/* Maybe it can talk to us, though we can't talk to it.
1784		 * (Includes HNP test device.)
1785		 */
1786		if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1787			err = usb_port_suspend(udev, PMSG_SUSPEND);
1788			if (err < 0)
1789				dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1790		}
1791		err = -ENOTSUPP;
1792		goto fail;
1793	}
1794fail:
1795#endif
1796	return err;
1797}
1798
1799
1800/**
1801 * usb_enumerate_device - Read device configs/intfs/otg (usbcore-internal)
1802 * @udev: newly addressed device (in ADDRESS state)
1803 *
1804 * This is only called by usb_new_device() and usb_authorize_device()
1805 * and FIXME -- all comments that apply to them apply here wrt to
1806 * environment.
1807 *
1808 * If the device is WUSB and not authorized, we don't attempt to read
1809 * the string descriptors, as they will be errored out by the device
1810 * until it has been authorized.
1811 */
1812static int usb_enumerate_device(struct usb_device *udev)
1813{
1814	int err;
1815
1816	if (udev->config == NULL) {
1817		err = usb_get_configuration(udev);
1818		if (err < 0) {
1819			dev_err(&udev->dev, "can't read configurations, error %d\n",
1820				err);
1821			goto fail;
1822		}
1823	}
1824	if (udev->wusb == 1 && udev->authorized == 0) {
1825		udev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1826		udev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1827		udev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1828	}
1829	else {
1830		/* read the standard strings and cache them if present */
1831		udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1832		udev->manufacturer = usb_cache_string(udev,
1833						      udev->descriptor.iManufacturer);
1834		udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1835	}
1836	err = usb_enumerate_device_otg(udev);
1837fail:
1838	return err;
1839}
1840
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1841
1842/**
1843 * usb_new_device - perform initial device setup (usbcore-internal)
1844 * @udev: newly addressed device (in ADDRESS state)
1845 *
1846 * This is called with devices which have been detected but not fully
1847 * enumerated.  The device descriptor is available, but not descriptors
1848 * for any device configuration.  The caller must have locked either
1849 * the parent hub (if udev is a normal device) or else the
1850 * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1851 * udev has already been installed, but udev is not yet visible through
1852 * sysfs or other filesystem code.
1853 *
1854 * It will return if the device is configured properly or not.  Zero if
1855 * the interface was registered with the driver core; else a negative
1856 * errno value.
1857 *
1858 * This call is synchronous, and may not be used in an interrupt context.
1859 *
1860 * Only the hub driver or root-hub registrar should ever call this.
1861 */
1862int usb_new_device(struct usb_device *udev)
1863{
1864	int err;
1865
1866	if (udev->parent) {
1867		/* Initialize non-root-hub device wakeup to disabled;
1868		 * device (un)configuration controls wakeup capable
1869		 * sysfs power/wakeup controls wakeup enabled/disabled
1870		 */
1871		device_init_wakeup(&udev->dev, 0);
1872	}
1873
1874	/* Tell the runtime-PM framework the device is active */
1875	pm_runtime_set_active(&udev->dev);
1876	pm_runtime_get_noresume(&udev->dev);
1877	pm_runtime_use_autosuspend(&udev->dev);
1878	pm_runtime_enable(&udev->dev);
1879
1880	/* By default, forbid autosuspend for all devices.  It will be
1881	 * allowed for hubs during binding.
1882	 */
1883	usb_disable_autosuspend(udev);
1884
1885	err = usb_enumerate_device(udev);	/* Read descriptors */
1886	if (err < 0)
1887		goto fail;
1888	dev_dbg(&udev->dev, "udev %d, busnum %d, minor = %d\n",
1889			udev->devnum, udev->bus->busnum,
1890			(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
1891	/* export the usbdev device-node for libusb */
1892	udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
1893			(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
1894
1895	/* Tell the world! */
1896	announce_device(udev);
1897
 
 
 
 
 
 
 
 
1898	device_enable_async_suspend(&udev->dev);
 
 
 
 
 
 
 
 
 
1899	/* Register the device.  The device driver is responsible
1900	 * for configuring the device and invoking the add-device
1901	 * notifier chain (used by usbfs and possibly others).
1902	 */
1903	err = device_add(&udev->dev);
1904	if (err) {
1905		dev_err(&udev->dev, "can't device_add, error %d\n", err);
1906		goto fail;
1907	}
1908
1909	(void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev);
1910	usb_mark_last_busy(udev);
1911	pm_runtime_put_sync_autosuspend(&udev->dev);
1912	return err;
1913
1914fail:
1915	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1916	pm_runtime_disable(&udev->dev);
1917	pm_runtime_set_suspended(&udev->dev);
1918	return err;
1919}
1920
1921
1922/**
1923 * usb_deauthorize_device - deauthorize a device (usbcore-internal)
1924 * @usb_dev: USB device
1925 *
1926 * Move the USB device to a very basic state where interfaces are disabled
1927 * and the device is in fact unconfigured and unusable.
1928 *
1929 * We share a lock (that we have) with device_del(), so we need to
1930 * defer its call.
1931 */
1932int usb_deauthorize_device(struct usb_device *usb_dev)
1933{
1934	usb_lock_device(usb_dev);
1935	if (usb_dev->authorized == 0)
1936		goto out_unauthorized;
1937
1938	usb_dev->authorized = 0;
1939	usb_set_configuration(usb_dev, -1);
1940
1941	kfree(usb_dev->product);
1942	usb_dev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1943	kfree(usb_dev->manufacturer);
1944	usb_dev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1945	kfree(usb_dev->serial);
1946	usb_dev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1947
1948	usb_destroy_configuration(usb_dev);
1949	usb_dev->descriptor.bNumConfigurations = 0;
1950
1951out_unauthorized:
1952	usb_unlock_device(usb_dev);
1953	return 0;
1954}
1955
1956
1957int usb_authorize_device(struct usb_device *usb_dev)
1958{
1959	int result = 0, c;
1960
1961	usb_lock_device(usb_dev);
1962	if (usb_dev->authorized == 1)
1963		goto out_authorized;
1964
1965	result = usb_autoresume_device(usb_dev);
1966	if (result < 0) {
1967		dev_err(&usb_dev->dev,
1968			"can't autoresume for authorization: %d\n", result);
1969		goto error_autoresume;
1970	}
1971	result = usb_get_device_descriptor(usb_dev, sizeof(usb_dev->descriptor));
1972	if (result < 0) {
1973		dev_err(&usb_dev->dev, "can't re-read device descriptor for "
1974			"authorization: %d\n", result);
1975		goto error_device_descriptor;
1976	}
1977
1978	kfree(usb_dev->product);
1979	usb_dev->product = NULL;
1980	kfree(usb_dev->manufacturer);
1981	usb_dev->manufacturer = NULL;
1982	kfree(usb_dev->serial);
1983	usb_dev->serial = NULL;
1984
1985	usb_dev->authorized = 1;
1986	result = usb_enumerate_device(usb_dev);
1987	if (result < 0)
1988		goto error_enumerate;
1989	/* Choose and set the configuration.  This registers the interfaces
1990	 * with the driver core and lets interface drivers bind to them.
1991	 */
1992	c = usb_choose_configuration(usb_dev);
1993	if (c >= 0) {
1994		result = usb_set_configuration(usb_dev, c);
1995		if (result) {
1996			dev_err(&usb_dev->dev,
1997				"can't set config #%d, error %d\n", c, result);
1998			/* This need not be fatal.  The user can try to
1999			 * set other configurations. */
2000		}
2001	}
2002	dev_info(&usb_dev->dev, "authorized to connect\n");
2003
2004error_enumerate:
2005error_device_descriptor:
2006	usb_autosuspend_device(usb_dev);
2007error_autoresume:
2008out_authorized:
2009	usb_unlock_device(usb_dev);	// complements locktree
2010	return result;
2011}
2012
2013
2014/* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
2015static unsigned hub_is_wusb(struct usb_hub *hub)
2016{
2017	struct usb_hcd *hcd;
2018	if (hub->hdev->parent != NULL)  /* not a root hub? */
2019		return 0;
2020	hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
2021	return hcd->wireless;
2022}
2023
2024
2025#define PORT_RESET_TRIES	5
2026#define SET_ADDRESS_TRIES	2
2027#define GET_DESCRIPTOR_TRIES	2
2028#define SET_CONFIG_TRIES	(2 * (use_both_schemes + 1))
2029#define USE_NEW_SCHEME(i)	((i) / 2 == old_scheme_first)
2030
2031#define HUB_ROOT_RESET_TIME	50	/* times are in msec */
2032#define HUB_SHORT_RESET_TIME	10
 
2033#define HUB_LONG_RESET_TIME	200
2034#define HUB_RESET_TIMEOUT	500
2035
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2036static int hub_port_wait_reset(struct usb_hub *hub, int port1,
2037				struct usb_device *udev, unsigned int delay)
2038{
2039	int delay_time, ret;
2040	u16 portstatus;
2041	u16 portchange;
2042
2043	for (delay_time = 0;
2044			delay_time < HUB_RESET_TIMEOUT;
2045			delay_time += delay) {
2046		/* wait to give the device a chance to reset */
2047		msleep(delay);
2048
2049		/* read and decode port status */
2050		ret = hub_port_status(hub, port1, &portstatus, &portchange);
2051		if (ret < 0)
2052			return ret;
2053
2054		/* Device went away? */
2055		if (!(portstatus & USB_PORT_STAT_CONNECTION))
2056			return -ENOTCONN;
2057
2058		/* bomb out completely if the connection bounced */
2059		if ((portchange & USB_PORT_STAT_C_CONNECTION))
2060			return -ENOTCONN;
2061
2062		/* if we`ve finished resetting, then break out of the loop */
2063		if (!(portstatus & USB_PORT_STAT_RESET) &&
2064		    (portstatus & USB_PORT_STAT_ENABLE)) {
2065			if (hub_is_wusb(hub))
2066				udev->speed = USB_SPEED_WIRELESS;
2067			else if (hub_is_superspeed(hub->hdev))
2068				udev->speed = USB_SPEED_SUPER;
2069			else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
2070				udev->speed = USB_SPEED_HIGH;
2071			else if (portstatus & USB_PORT_STAT_LOW_SPEED)
2072				udev->speed = USB_SPEED_LOW;
2073			else
2074				udev->speed = USB_SPEED_FULL;
2075			return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2076		}
2077
2078		/* switch to the long delay after two short delay failures */
2079		if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
2080			delay = HUB_LONG_RESET_TIME;
2081
2082		dev_dbg (hub->intfdev,
2083			"port %d not reset yet, waiting %dms\n",
2084			port1, delay);
2085	}
2086
2087	return -EBUSY;
2088}
2089
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2090static int hub_port_reset(struct usb_hub *hub, int port1,
2091				struct usb_device *udev, unsigned int delay)
2092{
2093	int i, status;
2094	struct usb_hcd *hcd;
2095
2096	hcd = bus_to_hcd(udev->bus);
2097	/* Block EHCI CF initialization during the port reset.
2098	 * Some companion controllers don't like it when they mix.
2099	 */
2100	down_read(&ehci_cf_port_reset_rwsem);
 
 
 
 
 
 
 
2101
2102	/* Reset the port */
2103	for (i = 0; i < PORT_RESET_TRIES; i++) {
2104		status = set_port_feature(hub->hdev,
2105				port1, USB_PORT_FEAT_RESET);
2106		if (status)
 
2107			dev_err(hub->intfdev,
2108					"cannot reset port %d (err = %d)\n",
2109					port1, status);
2110		else {
2111			status = hub_port_wait_reset(hub, port1, udev, delay);
 
2112			if (status && status != -ENOTCONN)
2113				dev_dbg(hub->intfdev,
2114						"port_wait_reset: err = %d\n",
2115						status);
2116		}
2117
2118		/* return on disconnect or reset */
2119		switch (status) {
2120		case 0:
2121			/* TRSTRCY = 10 ms; plus some extra */
2122			msleep(10 + 40);
2123			update_devnum(udev, 0);
2124			if (hcd->driver->reset_device) {
2125				status = hcd->driver->reset_device(hcd, udev);
2126				if (status < 0) {
2127					dev_err(&udev->dev, "Cannot reset "
2128							"HCD device state\n");
2129					break;
2130				}
2131			}
2132			/* FALL THROUGH */
2133		case -ENOTCONN:
2134		case -ENODEV:
2135			clear_port_feature(hub->hdev,
2136				port1, USB_PORT_FEAT_C_RESET);
2137			/* FIXME need disconnect() for NOTATTACHED device */
2138			usb_set_device_state(udev, status
2139					? USB_STATE_NOTATTACHED
2140					: USB_STATE_DEFAULT);
2141			goto done;
2142		}
2143
2144		dev_dbg (hub->intfdev,
2145			"port %d not enabled, trying reset again...\n",
2146			port1);
2147		delay = HUB_LONG_RESET_TIME;
2148	}
2149
2150	dev_err (hub->intfdev,
2151		"Cannot enable port %i.  Maybe the USB cable is bad?\n",
2152		port1);
2153
2154 done:
2155	up_read(&ehci_cf_port_reset_rwsem);
2156	return status;
2157}
2158
2159/* Warm reset a USB3 protocol port */
2160static int hub_port_warm_reset(struct usb_hub *hub, int port)
2161{
2162	int ret;
2163	u16 portstatus, portchange;
2164
2165	if (!hub_is_superspeed(hub->hdev)) {
2166		dev_err(hub->intfdev, "only USB3 hub support warm reset\n");
2167		return -EINVAL;
2168	}
2169
2170	/* Warm reset the port */
2171	ret = set_port_feature(hub->hdev,
2172				port, USB_PORT_FEAT_BH_PORT_RESET);
2173	if (ret) {
2174		dev_err(hub->intfdev, "cannot warm reset port %d\n", port);
2175		return ret;
2176	}
2177
2178	msleep(20);
2179	ret = hub_port_status(hub, port, &portstatus, &portchange);
2180
2181	if (portchange & USB_PORT_STAT_C_RESET)
2182		clear_port_feature(hub->hdev, port, USB_PORT_FEAT_C_RESET);
2183
2184	if (portchange & USB_PORT_STAT_C_BH_RESET)
2185		clear_port_feature(hub->hdev, port,
2186					USB_PORT_FEAT_C_BH_PORT_RESET);
2187
2188	if (portchange & USB_PORT_STAT_C_LINK_STATE)
2189		clear_port_feature(hub->hdev, port,
2190					USB_PORT_FEAT_C_PORT_LINK_STATE);
2191
2192	return ret;
2193}
2194
2195/* Check if a port is power on */
2196static int port_is_power_on(struct usb_hub *hub, unsigned portstatus)
2197{
2198	int ret = 0;
2199
2200	if (hub_is_superspeed(hub->hdev)) {
2201		if (portstatus & USB_SS_PORT_STAT_POWER)
2202			ret = 1;
2203	} else {
2204		if (portstatus & USB_PORT_STAT_POWER)
2205			ret = 1;
2206	}
2207
2208	return ret;
2209}
2210
2211#ifdef	CONFIG_PM
2212
2213/* Check if a port is suspended(USB2.0 port) or in U3 state(USB3.0 port) */
2214static int port_is_suspended(struct usb_hub *hub, unsigned portstatus)
2215{
2216	int ret = 0;
2217
2218	if (hub_is_superspeed(hub->hdev)) {
2219		if ((portstatus & USB_PORT_STAT_LINK_STATE)
2220				== USB_SS_PORT_LS_U3)
2221			ret = 1;
2222	} else {
2223		if (portstatus & USB_PORT_STAT_SUSPEND)
2224			ret = 1;
2225	}
2226
2227	return ret;
2228}
2229
2230/* Determine whether the device on a port is ready for a normal resume,
2231 * is ready for a reset-resume, or should be disconnected.
2232 */
2233static int check_port_resume_type(struct usb_device *udev,
2234		struct usb_hub *hub, int port1,
2235		int status, unsigned portchange, unsigned portstatus)
2236{
2237	/* Is the device still present? */
2238	if (status || port_is_suspended(hub, portstatus) ||
2239			!port_is_power_on(hub, portstatus) ||
2240			!(portstatus & USB_PORT_STAT_CONNECTION)) {
2241		if (status >= 0)
2242			status = -ENODEV;
2243	}
2244
2245	/* Can't do a normal resume if the port isn't enabled,
2246	 * so try a reset-resume instead.
2247	 */
2248	else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
2249		if (udev->persist_enabled)
2250			udev->reset_resume = 1;
2251		else
2252			status = -ENODEV;
2253	}
2254
2255	if (status) {
2256		dev_dbg(hub->intfdev,
2257				"port %d status %04x.%04x after resume, %d\n",
2258				port1, portchange, portstatus, status);
2259	} else if (udev->reset_resume) {
2260
2261		/* Late port handoff can set status-change bits */
2262		if (portchange & USB_PORT_STAT_C_CONNECTION)
2263			clear_port_feature(hub->hdev, port1,
2264					USB_PORT_FEAT_C_CONNECTION);
2265		if (portchange & USB_PORT_STAT_C_ENABLE)
2266			clear_port_feature(hub->hdev, port1,
2267					USB_PORT_FEAT_C_ENABLE);
2268	}
2269
2270	return status;
2271}
2272
2273#ifdef	CONFIG_USB_SUSPEND
2274
2275/*
2276 * usb_port_suspend - suspend a usb device's upstream port
2277 * @udev: device that's no longer in active use, not a root hub
2278 * Context: must be able to sleep; device not locked; pm locks held
2279 *
2280 * Suspends a USB device that isn't in active use, conserving power.
2281 * Devices may wake out of a suspend, if anything important happens,
2282 * using the remote wakeup mechanism.  They may also be taken out of
2283 * suspend by the host, using usb_port_resume().  It's also routine
2284 * to disconnect devices while they are suspended.
2285 *
2286 * This only affects the USB hardware for a device; its interfaces
2287 * (and, for hubs, child devices) must already have been suspended.
2288 *
2289 * Selective port suspend reduces power; most suspended devices draw
2290 * less than 500 uA.  It's also used in OTG, along with remote wakeup.
2291 * All devices below the suspended port are also suspended.
2292 *
2293 * Devices leave suspend state when the host wakes them up.  Some devices
2294 * also support "remote wakeup", where the device can activate the USB
2295 * tree above them to deliver data, such as a keypress or packet.  In
2296 * some cases, this wakes the USB host.
2297 *
2298 * Suspending OTG devices may trigger HNP, if that's been enabled
2299 * between a pair of dual-role devices.  That will change roles, such
2300 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
2301 *
2302 * Devices on USB hub ports have only one "suspend" state, corresponding
2303 * to ACPI D2, "may cause the device to lose some context".
2304 * State transitions include:
2305 *
2306 *   - suspend, resume ... when the VBUS power link stays live
2307 *   - suspend, disconnect ... VBUS lost
2308 *
2309 * Once VBUS drop breaks the circuit, the port it's using has to go through
2310 * normal re-enumeration procedures, starting with enabling VBUS power.
2311 * Other than re-initializing the hub (plug/unplug, except for root hubs),
2312 * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
2313 * timer, no SRP, no requests through sysfs.
2314 *
2315 * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
2316 * the root hub for their bus goes into global suspend ... so we don't
2317 * (falsely) update the device power state to say it suspended.
2318 *
2319 * Returns 0 on success, else negative errno.
2320 */
2321int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
2322{
2323	struct usb_hub	*hub = hdev_to_hub(udev->parent);
2324	int		port1 = udev->portnum;
2325	int		status;
2326
2327	// dev_dbg(hub->intfdev, "suspend port %d\n", port1);
2328
2329	/* enable remote wakeup when appropriate; this lets the device
2330	 * wake up the upstream hub (including maybe the root hub).
2331	 *
2332	 * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
2333	 * we don't explicitly enable it here.
2334	 */
2335	if (udev->do_remote_wakeup) {
2336		status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2337				USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
2338				USB_DEVICE_REMOTE_WAKEUP, 0,
2339				NULL, 0,
2340				USB_CTRL_SET_TIMEOUT);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2341		if (status) {
2342			dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
2343					status);
2344			/* bail if autosuspend is requested */
2345			if (msg.event & PM_EVENT_AUTO)
2346				return status;
2347		}
2348	}
2349
 
 
 
 
 
 
 
 
 
 
2350	/* see 7.1.7.6 */
2351	if (hub_is_superspeed(hub->hdev))
2352		status = set_port_feature(hub->hdev,
2353				port1 | (USB_SS_PORT_LS_U3 << 3),
2354				USB_PORT_FEAT_LINK_STATE);
2355	else
2356		status = set_port_feature(hub->hdev, port1,
2357						USB_PORT_FEAT_SUSPEND);
2358	if (status) {
2359		dev_dbg(hub->intfdev, "can't suspend port %d, status %d\n",
2360				port1, status);
2361		/* paranoia:  "should not happen" */
2362		if (udev->do_remote_wakeup)
2363			(void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2364				USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
2365				USB_DEVICE_REMOTE_WAKEUP, 0,
2366				NULL, 0,
2367				USB_CTRL_SET_TIMEOUT);
2368
 
 
 
 
 
 
 
2369		/* System sleep transitions should never fail */
2370		if (!(msg.event & PM_EVENT_AUTO))
2371			status = 0;
2372	} else {
2373		/* device has up to 10 msec to fully suspend */
2374		dev_dbg(&udev->dev, "usb %ssuspend\n",
2375				(msg.event & PM_EVENT_AUTO ? "auto-" : ""));
 
2376		usb_set_device_state(udev, USB_STATE_SUSPENDED);
2377		msleep(10);
2378	}
2379	usb_mark_last_busy(hub->hdev);
2380	return status;
2381}
2382
2383/*
2384 * If the USB "suspend" state is in use (rather than "global suspend"),
2385 * many devices will be individually taken out of suspend state using
2386 * special "resume" signaling.  This routine kicks in shortly after
2387 * hardware resume signaling is finished, either because of selective
2388 * resume (by host) or remote wakeup (by device) ... now see what changed
2389 * in the tree that's rooted at this device.
2390 *
2391 * If @udev->reset_resume is set then the device is reset before the
2392 * status check is done.
2393 */
2394static int finish_port_resume(struct usb_device *udev)
2395{
2396	int	status = 0;
2397	u16	devstatus;
2398
2399	/* caller owns the udev device lock */
2400	dev_dbg(&udev->dev, "%s\n",
2401		udev->reset_resume ? "finish reset-resume" : "finish resume");
2402
2403	/* usb ch9 identifies four variants of SUSPENDED, based on what
2404	 * state the device resumes to.  Linux currently won't see the
2405	 * first two on the host side; they'd be inside hub_port_init()
2406	 * during many timeouts, but khubd can't suspend until later.
2407	 */
2408	usb_set_device_state(udev, udev->actconfig
2409			? USB_STATE_CONFIGURED
2410			: USB_STATE_ADDRESS);
2411
2412	/* 10.5.4.5 says not to reset a suspended port if the attached
2413	 * device is enabled for remote wakeup.  Hence the reset
2414	 * operation is carried out here, after the port has been
2415	 * resumed.
2416	 */
2417	if (udev->reset_resume)
2418 retry_reset_resume:
2419		status = usb_reset_and_verify_device(udev);
2420
2421 	/* 10.5.4.5 says be sure devices in the tree are still there.
2422 	 * For now let's assume the device didn't go crazy on resume,
2423	 * and device drivers will know about any resume quirks.
2424	 */
2425	if (status == 0) {
2426		devstatus = 0;
2427		status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
2428		if (status >= 0)
2429			status = (status > 0 ? 0 : -ENODEV);
2430
2431		/* If a normal resume failed, try doing a reset-resume */
2432		if (status && !udev->reset_resume && udev->persist_enabled) {
2433			dev_dbg(&udev->dev, "retry with reset-resume\n");
2434			udev->reset_resume = 1;
2435			goto retry_reset_resume;
2436		}
2437	}
2438
2439	if (status) {
2440		dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
2441				status);
2442	} else if (udev->actconfig) {
2443		le16_to_cpus(&devstatus);
2444		if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
2445			status = usb_control_msg(udev,
2446					usb_sndctrlpipe(udev, 0),
2447					USB_REQ_CLEAR_FEATURE,
2448						USB_RECIP_DEVICE,
2449					USB_DEVICE_REMOTE_WAKEUP, 0,
2450					NULL, 0,
2451					USB_CTRL_SET_TIMEOUT);
2452			if (status)
2453				dev_dbg(&udev->dev,
2454					"disable remote wakeup, status %d\n",
2455					status);
2456		}
2457		status = 0;
2458	}
2459	return status;
2460}
2461
2462/*
2463 * usb_port_resume - re-activate a suspended usb device's upstream port
2464 * @udev: device to re-activate, not a root hub
2465 * Context: must be able to sleep; device not locked; pm locks held
2466 *
2467 * This will re-activate the suspended device, increasing power usage
2468 * while letting drivers communicate again with its endpoints.
2469 * USB resume explicitly guarantees that the power session between
2470 * the host and the device is the same as it was when the device
2471 * suspended.
2472 *
2473 * If @udev->reset_resume is set then this routine won't check that the
2474 * port is still enabled.  Furthermore, finish_port_resume() above will
2475 * reset @udev.  The end result is that a broken power session can be
2476 * recovered and @udev will appear to persist across a loss of VBUS power.
2477 *
2478 * For example, if a host controller doesn't maintain VBUS suspend current
2479 * during a system sleep or is reset when the system wakes up, all the USB
2480 * power sessions below it will be broken.  This is especially troublesome
2481 * for mass-storage devices containing mounted filesystems, since the
2482 * device will appear to have disconnected and all the memory mappings
2483 * to it will be lost.  Using the USB_PERSIST facility, the device can be
2484 * made to appear as if it had not disconnected.
2485 *
2486 * This facility can be dangerous.  Although usb_reset_and_verify_device() makes
2487 * every effort to insure that the same device is present after the
2488 * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
2489 * quite possible for a device to remain unaltered but its media to be
2490 * changed.  If the user replaces a flash memory card while the system is
2491 * asleep, he will have only himself to blame when the filesystem on the
2492 * new card is corrupted and the system crashes.
2493 *
2494 * Returns 0 on success, else negative errno.
2495 */
2496int usb_port_resume(struct usb_device *udev, pm_message_t msg)
2497{
2498	struct usb_hub	*hub = hdev_to_hub(udev->parent);
2499	int		port1 = udev->portnum;
2500	int		status;
2501	u16		portchange, portstatus;
2502
2503	/* Skip the initial Clear-Suspend step for a remote wakeup */
2504	status = hub_port_status(hub, port1, &portstatus, &portchange);
2505	if (status == 0 && !port_is_suspended(hub, portstatus))
2506		goto SuspendCleared;
2507
2508	// dev_dbg(hub->intfdev, "resume port %d\n", port1);
2509
2510	set_bit(port1, hub->busy_bits);
2511
2512	/* see 7.1.7.7; affects power usage, but not budgeting */
2513	if (hub_is_superspeed(hub->hdev))
2514		status = set_port_feature(hub->hdev,
2515				port1 | (USB_SS_PORT_LS_U0 << 3),
2516				USB_PORT_FEAT_LINK_STATE);
2517	else
2518		status = clear_port_feature(hub->hdev,
2519				port1, USB_PORT_FEAT_SUSPEND);
2520	if (status) {
2521		dev_dbg(hub->intfdev, "can't resume port %d, status %d\n",
2522				port1, status);
2523	} else {
2524		/* drive resume for at least 20 msec */
2525		dev_dbg(&udev->dev, "usb %sresume\n",
2526				(msg.event & PM_EVENT_AUTO ? "auto-" : ""));
2527		msleep(25);
2528
2529		/* Virtual root hubs can trigger on GET_PORT_STATUS to
2530		 * stop resume signaling.  Then finish the resume
2531		 * sequence.
2532		 */
2533		status = hub_port_status(hub, port1, &portstatus, &portchange);
2534
2535		/* TRSMRCY = 10 msec */
2536		msleep(10);
2537	}
2538
2539 SuspendCleared:
2540	if (status == 0) {
2541		if (hub_is_superspeed(hub->hdev)) {
2542			if (portchange & USB_PORT_STAT_C_LINK_STATE)
2543				clear_port_feature(hub->hdev, port1,
2544					USB_PORT_FEAT_C_PORT_LINK_STATE);
2545		} else {
2546			if (portchange & USB_PORT_STAT_C_SUSPEND)
2547				clear_port_feature(hub->hdev, port1,
2548						USB_PORT_FEAT_C_SUSPEND);
2549		}
2550	}
2551
2552	clear_bit(port1, hub->busy_bits);
2553
2554	status = check_port_resume_type(udev,
2555			hub, port1, status, portchange, portstatus);
2556	if (status == 0)
2557		status = finish_port_resume(udev);
2558	if (status < 0) {
2559		dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2560		hub_port_logical_disconnect(hub, port1);
 
 
 
 
 
 
 
2561	}
 
2562	return status;
2563}
2564
2565/* caller has locked udev */
2566int usb_remote_wakeup(struct usb_device *udev)
2567{
2568	int	status = 0;
2569
2570	if (udev->state == USB_STATE_SUSPENDED) {
2571		dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
2572		status = usb_autoresume_device(udev);
2573		if (status == 0) {
2574			/* Let the drivers do their thing, then... */
2575			usb_autosuspend_device(udev);
2576		}
2577	}
2578	return status;
2579}
2580
2581#else	/* CONFIG_USB_SUSPEND */
2582
2583/* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
2584
2585int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
2586{
2587	return 0;
2588}
2589
2590/* However we may need to do a reset-resume */
2591
2592int usb_port_resume(struct usb_device *udev, pm_message_t msg)
2593{
2594	struct usb_hub	*hub = hdev_to_hub(udev->parent);
2595	int		port1 = udev->portnum;
2596	int		status;
2597	u16		portchange, portstatus;
2598
2599	status = hub_port_status(hub, port1, &portstatus, &portchange);
2600	status = check_port_resume_type(udev,
2601			hub, port1, status, portchange, portstatus);
2602
2603	if (status) {
2604		dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2605		hub_port_logical_disconnect(hub, port1);
2606	} else if (udev->reset_resume) {
2607		dev_dbg(&udev->dev, "reset-resume\n");
2608		status = usb_reset_and_verify_device(udev);
2609	}
2610	return status;
2611}
2612
2613#endif
2614
2615static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
2616{
2617	struct usb_hub		*hub = usb_get_intfdata (intf);
2618	struct usb_device	*hdev = hub->hdev;
2619	unsigned		port1;
 
2620
2621	/* Warn if children aren't already suspended */
2622	for (port1 = 1; port1 <= hdev->maxchild; port1++) {
2623		struct usb_device	*udev;
2624
2625		udev = hdev->children [port1-1];
2626		if (udev && udev->can_submit) {
2627			dev_warn(&intf->dev, "port %d nyet suspended\n", port1);
2628			if (msg.event & PM_EVENT_AUTO)
2629				return -EBUSY;
2630		}
2631	}
 
 
 
 
 
 
 
 
 
 
 
2632
2633	dev_dbg(&intf->dev, "%s\n", __func__);
2634
2635	/* stop khubd and related activity */
2636	hub_quiesce(hub, HUB_SUSPEND);
2637	return 0;
2638}
2639
2640static int hub_resume(struct usb_interface *intf)
2641{
2642	struct usb_hub *hub = usb_get_intfdata(intf);
2643
2644	dev_dbg(&intf->dev, "%s\n", __func__);
2645	hub_activate(hub, HUB_RESUME);
2646	return 0;
2647}
2648
2649static int hub_reset_resume(struct usb_interface *intf)
2650{
2651	struct usb_hub *hub = usb_get_intfdata(intf);
2652
2653	dev_dbg(&intf->dev, "%s\n", __func__);
2654	hub_activate(hub, HUB_RESET_RESUME);
2655	return 0;
2656}
2657
2658/**
2659 * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
2660 * @rhdev: struct usb_device for the root hub
2661 *
2662 * The USB host controller driver calls this function when its root hub
2663 * is resumed and Vbus power has been interrupted or the controller
2664 * has been reset.  The routine marks @rhdev as having lost power.
2665 * When the hub driver is resumed it will take notice and carry out
2666 * power-session recovery for all the "USB-PERSIST"-enabled child devices;
2667 * the others will be disconnected.
2668 */
2669void usb_root_hub_lost_power(struct usb_device *rhdev)
2670{
2671	dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
2672	rhdev->reset_resume = 1;
2673}
2674EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
2675
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2676#else	/* CONFIG_PM */
2677
2678#define hub_suspend		NULL
2679#define hub_resume		NULL
2680#define hub_reset_resume	NULL
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2681#endif
2682
2683
2684/* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2685 *
2686 * Between connect detection and reset signaling there must be a delay
2687 * of 100ms at least for debounce and power-settling.  The corresponding
2688 * timer shall restart whenever the downstream port detects a disconnect.
2689 * 
2690 * Apparently there are some bluetooth and irda-dongles and a number of
2691 * low-speed devices for which this debounce period may last over a second.
2692 * Not covered by the spec - but easy to deal with.
2693 *
2694 * This implementation uses a 1500ms total debounce timeout; if the
2695 * connection isn't stable by then it returns -ETIMEDOUT.  It checks
2696 * every 25ms for transient disconnects.  When the port status has been
2697 * unchanged for 100ms it returns the port status.
2698 */
2699static int hub_port_debounce(struct usb_hub *hub, int port1)
2700{
2701	int ret;
2702	int total_time, stable_time = 0;
2703	u16 portchange, portstatus;
2704	unsigned connection = 0xffff;
2705
2706	for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2707		ret = hub_port_status(hub, port1, &portstatus, &portchange);
2708		if (ret < 0)
2709			return ret;
2710
2711		if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2712		     (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2713			stable_time += HUB_DEBOUNCE_STEP;
2714			if (stable_time >= HUB_DEBOUNCE_STABLE)
2715				break;
2716		} else {
2717			stable_time = 0;
2718			connection = portstatus & USB_PORT_STAT_CONNECTION;
2719		}
2720
2721		if (portchange & USB_PORT_STAT_C_CONNECTION) {
2722			clear_port_feature(hub->hdev, port1,
2723					USB_PORT_FEAT_C_CONNECTION);
2724		}
2725
2726		if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2727			break;
2728		msleep(HUB_DEBOUNCE_STEP);
2729	}
2730
2731	dev_dbg (hub->intfdev,
2732		"debounce: port %d: total %dms stable %dms status 0x%x\n",
2733		port1, total_time, stable_time, portstatus);
2734
2735	if (stable_time < HUB_DEBOUNCE_STABLE)
2736		return -ETIMEDOUT;
2737	return portstatus;
2738}
2739
2740void usb_ep0_reinit(struct usb_device *udev)
2741{
2742	usb_disable_endpoint(udev, 0 + USB_DIR_IN, true);
2743	usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true);
2744	usb_enable_endpoint(udev, &udev->ep0, true);
2745}
2746EXPORT_SYMBOL_GPL(usb_ep0_reinit);
2747
2748#define usb_sndaddr0pipe()	(PIPE_CONTROL << 30)
2749#define usb_rcvaddr0pipe()	((PIPE_CONTROL << 30) | USB_DIR_IN)
2750
2751static int hub_set_address(struct usb_device *udev, int devnum)
2752{
2753	int retval;
2754	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2755
2756	/*
2757	 * The host controller will choose the device address,
2758	 * instead of the core having chosen it earlier
2759	 */
2760	if (!hcd->driver->address_device && devnum <= 1)
2761		return -EINVAL;
2762	if (udev->state == USB_STATE_ADDRESS)
2763		return 0;
2764	if (udev->state != USB_STATE_DEFAULT)
2765		return -EINVAL;
2766	if (hcd->driver->address_device)
2767		retval = hcd->driver->address_device(hcd, udev);
2768	else
2769		retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2770				USB_REQ_SET_ADDRESS, 0, devnum, 0,
2771				NULL, 0, USB_CTRL_SET_TIMEOUT);
2772	if (retval == 0) {
2773		update_devnum(udev, devnum);
2774		/* Device now using proper address. */
2775		usb_set_device_state(udev, USB_STATE_ADDRESS);
2776		usb_ep0_reinit(udev);
2777	}
2778	return retval;
2779}
2780
2781/* Reset device, (re)assign address, get device descriptor.
2782 * Device connection must be stable, no more debouncing needed.
2783 * Returns device in USB_STATE_ADDRESS, except on error.
2784 *
2785 * If this is called for an already-existing device (as part of
2786 * usb_reset_and_verify_device), the caller must own the device lock.  For a
2787 * newly detected device that is not accessible through any global
2788 * pointers, it's not necessary to lock the device.
2789 */
2790static int
2791hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2792		int retry_counter)
2793{
2794	static DEFINE_MUTEX(usb_address0_mutex);
2795
2796	struct usb_device	*hdev = hub->hdev;
2797	struct usb_hcd		*hcd = bus_to_hcd(hdev->bus);
2798	int			i, j, retval;
2799	unsigned		delay = HUB_SHORT_RESET_TIME;
2800	enum usb_device_speed	oldspeed = udev->speed;
2801	char 			*speed, *type;
2802	int			devnum = udev->devnum;
2803
2804	/* root hub ports have a slightly longer reset period
2805	 * (from USB 2.0 spec, section 7.1.7.5)
2806	 */
2807	if (!hdev->parent) {
2808		delay = HUB_ROOT_RESET_TIME;
2809		if (port1 == hdev->bus->otg_port)
2810			hdev->bus->b_hnp_enable = 0;
2811	}
2812
2813	/* Some low speed devices have problems with the quick delay, so */
2814	/*  be a bit pessimistic with those devices. RHbug #23670 */
2815	if (oldspeed == USB_SPEED_LOW)
2816		delay = HUB_LONG_RESET_TIME;
2817
2818	mutex_lock(&usb_address0_mutex);
2819
2820	/* Reset the device; full speed may morph to high speed */
2821	/* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */
2822	retval = hub_port_reset(hub, port1, udev, delay);
2823	if (retval < 0)		/* error or disconnect */
2824		goto fail;
2825	/* success, speed is known */
2826
2827	retval = -ENODEV;
2828
2829	if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2830		dev_dbg(&udev->dev, "device reset changed speed!\n");
2831		goto fail;
2832	}
2833	oldspeed = udev->speed;
2834
2835	/* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2836	 * it's fixed size except for full speed devices.
2837	 * For Wireless USB devices, ep0 max packet is always 512 (tho
2838	 * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
2839	 */
2840	switch (udev->speed) {
2841	case USB_SPEED_SUPER:
2842	case USB_SPEED_WIRELESS:	/* fixed at 512 */
2843		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
2844		break;
2845	case USB_SPEED_HIGH:		/* fixed at 64 */
2846		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
2847		break;
2848	case USB_SPEED_FULL:		/* 8, 16, 32, or 64 */
2849		/* to determine the ep0 maxpacket size, try to read
2850		 * the device descriptor to get bMaxPacketSize0 and
2851		 * then correct our initial guess.
2852		 */
2853		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
2854		break;
2855	case USB_SPEED_LOW:		/* fixed at 8 */
2856		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(8);
2857		break;
2858	default:
2859		goto fail;
2860	}
2861 
2862	type = "";
2863	switch (udev->speed) {
2864	case USB_SPEED_LOW:	speed = "low";	break;
2865	case USB_SPEED_FULL:	speed = "full";	break;
2866	case USB_SPEED_HIGH:	speed = "high";	break;
2867	case USB_SPEED_SUPER:
2868				speed = "super";
2869				break;
2870	case USB_SPEED_WIRELESS:
2871				speed = "variable";
2872				type = "Wireless ";
2873				break;
2874	default: 		speed = "?";	break;
2875	}
2876	if (udev->speed != USB_SPEED_SUPER)
2877		dev_info(&udev->dev,
2878				"%s %s speed %sUSB device number %d using %s\n",
2879				(udev->config) ? "reset" : "new", speed, type,
2880				devnum, udev->bus->controller->driver->name);
2881
2882	/* Set up TT records, if needed  */
2883	if (hdev->tt) {
2884		udev->tt = hdev->tt;
2885		udev->ttport = hdev->ttport;
2886	} else if (udev->speed != USB_SPEED_HIGH
2887			&& hdev->speed == USB_SPEED_HIGH) {
2888		if (!hub->tt.hub) {
2889			dev_err(&udev->dev, "parent hub has no TT\n");
2890			retval = -EINVAL;
2891			goto fail;
2892		}
2893		udev->tt = &hub->tt;
2894		udev->ttport = port1;
2895	}
2896 
2897	/* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2898	 * Because device hardware and firmware is sometimes buggy in
2899	 * this area, and this is how Linux has done it for ages.
2900	 * Change it cautiously.
2901	 *
2902	 * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2903	 * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2904	 * so it may help with some non-standards-compliant devices.
2905	 * Otherwise we start with SET_ADDRESS and then try to read the
2906	 * first 8 bytes of the device descriptor to get the ep0 maxpacket
2907	 * value.
2908	 */
2909	for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2910		if (USE_NEW_SCHEME(retry_counter) && !(hcd->driver->flags & HCD_USB3)) {
2911			struct usb_device_descriptor *buf;
2912			int r = 0;
2913
2914#define GET_DESCRIPTOR_BUFSIZE	64
2915			buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2916			if (!buf) {
2917				retval = -ENOMEM;
2918				continue;
2919			}
2920
2921			/* Retry on all errors; some devices are flakey.
2922			 * 255 is for WUSB devices, we actually need to use
2923			 * 512 (WUSB1.0[4.8.1]).
2924			 */
2925			for (j = 0; j < 3; ++j) {
2926				buf->bMaxPacketSize0 = 0;
2927				r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2928					USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2929					USB_DT_DEVICE << 8, 0,
2930					buf, GET_DESCRIPTOR_BUFSIZE,
2931					initial_descriptor_timeout);
2932				switch (buf->bMaxPacketSize0) {
2933				case 8: case 16: case 32: case 64: case 255:
2934					if (buf->bDescriptorType ==
2935							USB_DT_DEVICE) {
2936						r = 0;
2937						break;
2938					}
2939					/* FALL THROUGH */
2940				default:
2941					if (r == 0)
2942						r = -EPROTO;
2943					break;
2944				}
2945				if (r == 0)
2946					break;
2947			}
2948			udev->descriptor.bMaxPacketSize0 =
2949					buf->bMaxPacketSize0;
2950			kfree(buf);
2951
2952			retval = hub_port_reset(hub, port1, udev, delay);
2953			if (retval < 0)		/* error or disconnect */
2954				goto fail;
2955			if (oldspeed != udev->speed) {
2956				dev_dbg(&udev->dev,
2957					"device reset changed speed!\n");
2958				retval = -ENODEV;
2959				goto fail;
2960			}
2961			if (r) {
2962				dev_err(&udev->dev,
2963					"device descriptor read/64, error %d\n",
2964					r);
2965				retval = -EMSGSIZE;
2966				continue;
2967			}
2968#undef GET_DESCRIPTOR_BUFSIZE
2969		}
2970
2971 		/*
2972 		 * If device is WUSB, we already assigned an
2973 		 * unauthorized address in the Connect Ack sequence;
2974 		 * authorization will assign the final address.
2975 		 */
2976		if (udev->wusb == 0) {
2977			for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2978				retval = hub_set_address(udev, devnum);
2979				if (retval >= 0)
2980					break;
2981				msleep(200);
2982			}
2983			if (retval < 0) {
2984				dev_err(&udev->dev,
2985					"device not accepting address %d, error %d\n",
2986					devnum, retval);
2987				goto fail;
2988			}
2989			if (udev->speed == USB_SPEED_SUPER) {
2990				devnum = udev->devnum;
2991				dev_info(&udev->dev,
2992						"%s SuperSpeed USB device number %d using %s\n",
2993						(udev->config) ? "reset" : "new",
2994						devnum, udev->bus->controller->driver->name);
2995			}
2996
2997			/* cope with hardware quirkiness:
2998			 *  - let SET_ADDRESS settle, some device hardware wants it
2999			 *  - read ep0 maxpacket even for high and low speed,
3000			 */
3001			msleep(10);
3002			if (USE_NEW_SCHEME(retry_counter) && !(hcd->driver->flags & HCD_USB3))
3003				break;
3004  		}
3005
3006		retval = usb_get_device_descriptor(udev, 8);
3007		if (retval < 8) {
3008			dev_err(&udev->dev,
3009					"device descriptor read/8, error %d\n",
3010					retval);
3011			if (retval >= 0)
3012				retval = -EMSGSIZE;
3013		} else {
3014			retval = 0;
3015			break;
3016		}
3017	}
3018	if (retval)
3019		goto fail;
3020
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3021	if (udev->descriptor.bMaxPacketSize0 == 0xff ||
3022			udev->speed == USB_SPEED_SUPER)
3023		i = 512;
3024	else
3025		i = udev->descriptor.bMaxPacketSize0;
3026	if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
3027		if (udev->speed == USB_SPEED_LOW ||
3028				!(i == 8 || i == 16 || i == 32 || i == 64)) {
3029			dev_err(&udev->dev, "Invalid ep0 maxpacket: %d\n", i);
3030			retval = -EMSGSIZE;
3031			goto fail;
3032		}
3033		if (udev->speed == USB_SPEED_FULL)
3034			dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
3035		else
3036			dev_warn(&udev->dev, "Using ep0 maxpacket: %d\n", i);
3037		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
3038		usb_ep0_reinit(udev);
3039	}
3040  
3041	retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
3042	if (retval < (signed)sizeof(udev->descriptor)) {
3043		dev_err(&udev->dev, "device descriptor read/all, error %d\n",
3044			retval);
3045		if (retval >= 0)
3046			retval = -ENOMSG;
3047		goto fail;
3048	}
3049
 
 
 
 
 
 
 
 
3050	retval = 0;
3051	/* notify HCD that we have a device connected and addressed */
3052	if (hcd->driver->update_device)
3053		hcd->driver->update_device(hcd, udev);
3054fail:
3055	if (retval) {
3056		hub_port_disable(hub, port1, 0);
3057		update_devnum(udev, devnum);	/* for disconnect processing */
3058	}
3059	mutex_unlock(&usb_address0_mutex);
3060	return retval;
3061}
3062
3063static void
3064check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
3065{
3066	struct usb_qualifier_descriptor	*qual;
3067	int				status;
3068
3069	qual = kmalloc (sizeof *qual, GFP_KERNEL);
3070	if (qual == NULL)
3071		return;
3072
3073	status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
3074			qual, sizeof *qual);
3075	if (status == sizeof *qual) {
3076		dev_info(&udev->dev, "not running at top speed; "
3077			"connect to a high speed hub\n");
3078		/* hub LEDs are probably harder to miss than syslog */
3079		if (hub->has_indicators) {
3080			hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
3081			schedule_delayed_work (&hub->leds, 0);
3082		}
3083	}
3084	kfree(qual);
3085}
3086
3087static unsigned
3088hub_power_remaining (struct usb_hub *hub)
3089{
3090	struct usb_device *hdev = hub->hdev;
3091	int remaining;
3092	int port1;
3093
3094	if (!hub->limited_power)
3095		return 0;
3096
3097	remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
3098	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
3099		struct usb_device	*udev = hdev->children[port1 - 1];
3100		int			delta;
3101
3102		if (!udev)
3103			continue;
3104
3105		/* Unconfigured devices may not use more than 100mA,
3106		 * or 8mA for OTG ports */
3107		if (udev->actconfig)
3108			delta = udev->actconfig->desc.bMaxPower * 2;
3109		else if (port1 != udev->bus->otg_port || hdev->parent)
3110			delta = 100;
3111		else
3112			delta = 8;
3113		if (delta > hub->mA_per_port)
3114			dev_warn(&udev->dev,
3115				 "%dmA is over %umA budget for port %d!\n",
3116				 delta, hub->mA_per_port, port1);
3117		remaining -= delta;
3118	}
3119	if (remaining < 0) {
3120		dev_warn(hub->intfdev, "%dmA over power budget!\n",
3121			- remaining);
3122		remaining = 0;
3123	}
3124	return remaining;
3125}
3126
3127/* Handle physical or logical connection change events.
3128 * This routine is called when:
3129 * 	a port connection-change occurs;
3130 *	a port enable-change occurs (often caused by EMI);
3131 *	usb_reset_and_verify_device() encounters changed descriptors (as from
3132 *		a firmware download)
3133 * caller already locked the hub
3134 */
3135static void hub_port_connect_change(struct usb_hub *hub, int port1,
3136					u16 portstatus, u16 portchange)
3137{
3138	struct usb_device *hdev = hub->hdev;
3139	struct device *hub_dev = hub->intfdev;
3140	struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
3141	unsigned wHubCharacteristics =
3142			le16_to_cpu(hub->descriptor->wHubCharacteristics);
3143	struct usb_device *udev;
3144	int status, i;
3145
3146	dev_dbg (hub_dev,
3147		"port %d, status %04x, change %04x, %s\n",
3148		port1, portstatus, portchange, portspeed(hub, portstatus));
3149
3150	if (hub->has_indicators) {
3151		set_port_led(hub, port1, HUB_LED_AUTO);
3152		hub->indicator[port1-1] = INDICATOR_AUTO;
3153	}
3154
3155#ifdef	CONFIG_USB_OTG
3156	/* during HNP, don't repeat the debounce */
3157	if (hdev->bus->is_b_host)
3158		portchange &= ~(USB_PORT_STAT_C_CONNECTION |
3159				USB_PORT_STAT_C_ENABLE);
3160#endif
3161
3162	/* Try to resuscitate an existing device */
3163	udev = hdev->children[port1-1];
3164	if ((portstatus & USB_PORT_STAT_CONNECTION) && udev &&
3165			udev->state != USB_STATE_NOTATTACHED) {
3166		usb_lock_device(udev);
3167		if (portstatus & USB_PORT_STAT_ENABLE) {
3168			status = 0;		/* Nothing to do */
3169
3170#ifdef CONFIG_USB_SUSPEND
3171		} else if (udev->state == USB_STATE_SUSPENDED &&
3172				udev->persist_enabled) {
3173			/* For a suspended device, treat this as a
3174			 * remote wakeup event.
3175			 */
3176			status = usb_remote_wakeup(udev);
3177#endif
3178
3179		} else {
3180			status = -ENODEV;	/* Don't resuscitate */
3181		}
3182		usb_unlock_device(udev);
3183
3184		if (status == 0) {
3185			clear_bit(port1, hub->change_bits);
3186			return;
3187		}
3188	}
3189
3190	/* Disconnect any existing devices under this port */
3191	if (udev)
3192		usb_disconnect(&hdev->children[port1-1]);
3193	clear_bit(port1, hub->change_bits);
3194
3195	/* We can forget about a "removed" device when there's a physical
3196	 * disconnect or the connect status changes.
3197	 */
3198	if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
3199			(portchange & USB_PORT_STAT_C_CONNECTION))
3200		clear_bit(port1, hub->removed_bits);
3201
3202	if (portchange & (USB_PORT_STAT_C_CONNECTION |
3203				USB_PORT_STAT_C_ENABLE)) {
3204		status = hub_port_debounce(hub, port1);
3205		if (status < 0) {
3206			if (printk_ratelimit())
3207				dev_err(hub_dev, "connect-debounce failed, "
3208						"port %d disabled\n", port1);
3209			portstatus &= ~USB_PORT_STAT_CONNECTION;
3210		} else {
3211			portstatus = status;
3212		}
3213	}
3214
3215	/* Return now if debouncing failed or nothing is connected or
3216	 * the device was "removed".
3217	 */
3218	if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
3219			test_bit(port1, hub->removed_bits)) {
3220
3221		/* maybe switch power back on (e.g. root hub was reset) */
3222		if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
3223				&& !port_is_power_on(hub, portstatus))
3224			set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
3225
3226		if (portstatus & USB_PORT_STAT_ENABLE)
3227  			goto done;
3228		return;
3229	}
3230
3231	for (i = 0; i < SET_CONFIG_TRIES; i++) {
3232
3233		/* reallocate for each attempt, since references
3234		 * to the previous one can escape in various ways
3235		 */
3236		udev = usb_alloc_dev(hdev, hdev->bus, port1);
3237		if (!udev) {
3238			dev_err (hub_dev,
3239				"couldn't allocate port %d usb_device\n",
3240				port1);
3241			goto done;
3242		}
3243
3244		usb_set_device_state(udev, USB_STATE_POWERED);
3245 		udev->bus_mA = hub->mA_per_port;
3246		udev->level = hdev->level + 1;
3247		udev->wusb = hub_is_wusb(hub);
3248
3249		/* Only USB 3.0 devices are connected to SuperSpeed hubs. */
3250		if (hub_is_superspeed(hub->hdev))
3251			udev->speed = USB_SPEED_SUPER;
3252		else
3253			udev->speed = USB_SPEED_UNKNOWN;
3254
3255		choose_devnum(udev);
3256		if (udev->devnum <= 0) {
3257			status = -ENOTCONN;	/* Don't retry */
3258			goto loop;
3259		}
3260
3261		/* reset (non-USB 3.0 devices) and get descriptor */
3262		status = hub_port_init(hub, udev, port1, i);
3263		if (status < 0)
3264			goto loop;
3265
3266		usb_detect_quirks(udev);
3267		if (udev->quirks & USB_QUIRK_DELAY_INIT)
3268			msleep(1000);
3269
3270		/* consecutive bus-powered hubs aren't reliable; they can
3271		 * violate the voltage drop budget.  if the new child has
3272		 * a "powered" LED, users should notice we didn't enable it
3273		 * (without reading syslog), even without per-port LEDs
3274		 * on the parent.
3275		 */
3276		if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
3277				&& udev->bus_mA <= 100) {
3278			u16	devstat;
3279
3280			status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
3281					&devstat);
3282			if (status < 2) {
3283				dev_dbg(&udev->dev, "get status %d ?\n", status);
3284				goto loop_disable;
3285			}
3286			le16_to_cpus(&devstat);
3287			if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
3288				dev_err(&udev->dev,
3289					"can't connect bus-powered hub "
3290					"to this port\n");
3291				if (hub->has_indicators) {
3292					hub->indicator[port1-1] =
3293						INDICATOR_AMBER_BLINK;
3294					schedule_delayed_work (&hub->leds, 0);
3295				}
3296				status = -ENOTCONN;	/* Don't retry */
3297				goto loop_disable;
3298			}
3299		}
3300 
3301		/* check for devices running slower than they could */
3302		if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
3303				&& udev->speed == USB_SPEED_FULL
3304				&& highspeed_hubs != 0)
3305			check_highspeed (hub, udev, port1);
3306
3307		/* Store the parent's children[] pointer.  At this point
3308		 * udev becomes globally accessible, although presumably
3309		 * no one will look at it until hdev is unlocked.
3310		 */
3311		status = 0;
3312
3313		/* We mustn't add new devices if the parent hub has
3314		 * been disconnected; we would race with the
3315		 * recursively_mark_NOTATTACHED() routine.
3316		 */
3317		spin_lock_irq(&device_state_lock);
3318		if (hdev->state == USB_STATE_NOTATTACHED)
3319			status = -ENOTCONN;
3320		else
3321			hdev->children[port1-1] = udev;
3322		spin_unlock_irq(&device_state_lock);
3323
3324		/* Run it through the hoops (find a driver, etc) */
3325		if (!status) {
3326			status = usb_new_device(udev);
3327			if (status) {
3328				spin_lock_irq(&device_state_lock);
3329				hdev->children[port1-1] = NULL;
3330				spin_unlock_irq(&device_state_lock);
3331			}
3332		}
3333
3334		if (status)
3335			goto loop_disable;
3336
3337		status = hub_power_remaining(hub);
3338		if (status)
3339			dev_dbg(hub_dev, "%dmA power budget left\n", status);
3340
3341		return;
3342
3343loop_disable:
3344		hub_port_disable(hub, port1, 1);
3345loop:
3346		usb_ep0_reinit(udev);
3347		release_devnum(udev);
3348		hub_free_dev(udev);
3349		usb_put_dev(udev);
3350		if ((status == -ENOTCONN) || (status == -ENOTSUPP))
3351			break;
3352	}
3353	if (hub->hdev->parent ||
3354			!hcd->driver->port_handed_over ||
3355			!(hcd->driver->port_handed_over)(hcd, port1))
3356		dev_err(hub_dev, "unable to enumerate USB device on port %d\n",
3357				port1);
3358 
3359done:
3360	hub_port_disable(hub, port1, 1);
3361	if (hcd->driver->relinquish_port && !hub->hdev->parent)
3362		hcd->driver->relinquish_port(hcd, port1);
3363}
3364
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3365static void hub_events(void)
3366{
3367	struct list_head *tmp;
3368	struct usb_device *hdev;
3369	struct usb_interface *intf;
3370	struct usb_hub *hub;
3371	struct device *hub_dev;
3372	u16 hubstatus;
3373	u16 hubchange;
3374	u16 portstatus;
3375	u16 portchange;
3376	int i, ret;
3377	int connect_change;
3378
3379	/*
3380	 *  We restart the list every time to avoid a deadlock with
3381	 * deleting hubs downstream from this one. This should be
3382	 * safe since we delete the hub from the event list.
3383	 * Not the most efficient, but avoids deadlocks.
3384	 */
3385	while (1) {
3386
3387		/* Grab the first entry at the beginning of the list */
3388		spin_lock_irq(&hub_event_lock);
3389		if (list_empty(&hub_event_list)) {
3390			spin_unlock_irq(&hub_event_lock);
3391			break;
3392		}
3393
3394		tmp = hub_event_list.next;
3395		list_del_init(tmp);
3396
3397		hub = list_entry(tmp, struct usb_hub, event_list);
3398		kref_get(&hub->kref);
3399		spin_unlock_irq(&hub_event_lock);
3400
3401		hdev = hub->hdev;
3402		hub_dev = hub->intfdev;
3403		intf = to_usb_interface(hub_dev);
3404		dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
3405				hdev->state, hub->descriptor
3406					? hub->descriptor->bNbrPorts
3407					: 0,
3408				/* NOTE: expects max 15 ports... */
3409				(u16) hub->change_bits[0],
3410				(u16) hub->event_bits[0]);
3411
3412		/* Lock the device, then check to see if we were
3413		 * disconnected while waiting for the lock to succeed. */
3414		usb_lock_device(hdev);
3415		if (unlikely(hub->disconnected))
3416			goto loop_disconnected;
3417
3418		/* If the hub has died, clean up after it */
3419		if (hdev->state == USB_STATE_NOTATTACHED) {
3420			hub->error = -ENODEV;
3421			hub_quiesce(hub, HUB_DISCONNECT);
3422			goto loop;
3423		}
3424
3425		/* Autoresume */
3426		ret = usb_autopm_get_interface(intf);
3427		if (ret) {
3428			dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
3429			goto loop;
3430		}
3431
3432		/* If this is an inactive hub, do nothing */
3433		if (hub->quiescing)
3434			goto loop_autopm;
3435
3436		if (hub->error) {
3437			dev_dbg (hub_dev, "resetting for error %d\n",
3438				hub->error);
3439
3440			ret = usb_reset_device(hdev);
3441			if (ret) {
3442				dev_dbg (hub_dev,
3443					"error resetting hub: %d\n", ret);
3444				goto loop_autopm;
3445			}
3446
3447			hub->nerrors = 0;
3448			hub->error = 0;
3449		}
3450
3451		/* deal with port status changes */
3452		for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
3453			if (test_bit(i, hub->busy_bits))
3454				continue;
3455			connect_change = test_bit(i, hub->change_bits);
 
3456			if (!test_and_clear_bit(i, hub->event_bits) &&
3457					!connect_change)
3458				continue;
3459
3460			ret = hub_port_status(hub, i,
3461					&portstatus, &portchange);
3462			if (ret < 0)
3463				continue;
3464
3465			if (portchange & USB_PORT_STAT_C_CONNECTION) {
3466				clear_port_feature(hdev, i,
3467					USB_PORT_FEAT_C_CONNECTION);
3468				connect_change = 1;
3469			}
3470
3471			if (portchange & USB_PORT_STAT_C_ENABLE) {
3472				if (!connect_change)
3473					dev_dbg (hub_dev,
3474						"port %d enable change, "
3475						"status %08x\n",
3476						i, portstatus);
3477				clear_port_feature(hdev, i,
3478					USB_PORT_FEAT_C_ENABLE);
3479
3480				/*
3481				 * EM interference sometimes causes badly
3482				 * shielded USB devices to be shutdown by
3483				 * the hub, this hack enables them again.
3484				 * Works at least with mouse driver. 
3485				 */
3486				if (!(portstatus & USB_PORT_STAT_ENABLE)
3487				    && !connect_change
3488				    && hdev->children[i-1]) {
3489					dev_err (hub_dev,
3490					    "port %i "
3491					    "disabled by hub (EMI?), "
3492					    "re-enabling...\n",
3493						i);
3494					connect_change = 1;
3495				}
3496			}
3497
3498			if (portchange & USB_PORT_STAT_C_SUSPEND) {
3499				struct usb_device *udev;
 
3500
3501				clear_port_feature(hdev, i,
3502					USB_PORT_FEAT_C_SUSPEND);
3503				udev = hdev->children[i-1];
3504				if (udev) {
3505					/* TRSMRCY = 10 msec */
3506					msleep(10);
3507
3508					usb_lock_device(udev);
3509					ret = usb_remote_wakeup(hdev->
3510							children[i-1]);
3511					usb_unlock_device(udev);
3512					if (ret < 0)
3513						connect_change = 1;
3514				} else {
3515					ret = -ENODEV;
3516					hub_port_disable(hub, i, 1);
3517				}
3518				dev_dbg (hub_dev,
3519					"resume on port %d, status %d\n",
3520					i, ret);
3521			}
3522			
3523			if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
3524				u16 status = 0;
3525				u16 unused;
3526
3527				dev_dbg(hub_dev, "over-current change on port "
3528					"%d\n", i);
3529				clear_port_feature(hdev, i,
3530					USB_PORT_FEAT_C_OVER_CURRENT);
3531				msleep(100);	/* Cool down */
3532				hub_power_on(hub, true);
3533				hub_port_status(hub, i, &status, &unused);
3534				if (status & USB_PORT_STAT_OVERCURRENT)
3535					dev_err(hub_dev, "over-current "
3536						"condition on port %d\n", i);
3537			}
3538
3539			if (portchange & USB_PORT_STAT_C_RESET) {
3540				dev_dbg (hub_dev,
3541					"reset change on port %d\n",
3542					i);
3543				clear_port_feature(hdev, i,
3544					USB_PORT_FEAT_C_RESET);
3545			}
3546			if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
3547					hub_is_superspeed(hub->hdev)) {
3548				dev_dbg(hub_dev,
3549					"warm reset change on port %d\n",
3550					i);
3551				clear_port_feature(hdev, i,
3552					USB_PORT_FEAT_C_BH_PORT_RESET);
3553			}
3554			if (portchange & USB_PORT_STAT_C_LINK_STATE) {
3555				clear_port_feature(hub->hdev, i,
3556						USB_PORT_FEAT_C_PORT_LINK_STATE);
3557			}
3558			if (portchange & USB_PORT_STAT_C_CONFIG_ERROR) {
3559				dev_warn(hub_dev,
3560					"config error on port %d\n",
3561					i);
3562				clear_port_feature(hub->hdev, i,
3563						USB_PORT_FEAT_C_PORT_CONFIG_ERROR);
3564			}
3565
3566			/* Warm reset a USB3 protocol port if it's in
3567			 * SS.Inactive state.
3568			 */
3569			if (hub_is_superspeed(hub->hdev) &&
3570				(portstatus & USB_PORT_STAT_LINK_STATE)
3571					== USB_SS_PORT_LS_SS_INACTIVE) {
3572				dev_dbg(hub_dev, "warm reset port %d\n", i);
3573				hub_port_warm_reset(hub, i);
 
3574			}
3575
3576			if (connect_change)
3577				hub_port_connect_change(hub, i,
3578						portstatus, portchange);
3579		} /* end for i */
3580
3581		/* deal with hub status changes */
3582		if (test_and_clear_bit(0, hub->event_bits) == 0)
3583			;	/* do nothing */
3584		else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
3585			dev_err (hub_dev, "get_hub_status failed\n");
3586		else {
3587			if (hubchange & HUB_CHANGE_LOCAL_POWER) {
3588				dev_dbg (hub_dev, "power change\n");
3589				clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
3590				if (hubstatus & HUB_STATUS_LOCAL_POWER)
3591					/* FIXME: Is this always true? */
3592					hub->limited_power = 1;
3593				else
3594					hub->limited_power = 0;
3595			}
3596			if (hubchange & HUB_CHANGE_OVERCURRENT) {
3597				u16 status = 0;
3598				u16 unused;
3599
3600				dev_dbg(hub_dev, "over-current change\n");
3601				clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
3602				msleep(500);	/* Cool down */
3603                        	hub_power_on(hub, true);
3604				hub_hub_status(hub, &status, &unused);
3605				if (status & HUB_STATUS_OVERCURRENT)
3606					dev_err(hub_dev, "over-current "
3607						"condition\n");
3608			}
3609		}
3610
3611 loop_autopm:
3612		/* Balance the usb_autopm_get_interface() above */
3613		usb_autopm_put_interface_no_suspend(intf);
3614 loop:
3615		/* Balance the usb_autopm_get_interface_no_resume() in
3616		 * kick_khubd() and allow autosuspend.
3617		 */
3618		usb_autopm_put_interface(intf);
3619 loop_disconnected:
3620		usb_unlock_device(hdev);
3621		kref_put(&hub->kref, hub_release);
3622
3623        } /* end while (1) */
3624}
3625
3626static int hub_thread(void *__unused)
3627{
3628	/* khubd needs to be freezable to avoid intefering with USB-PERSIST
3629	 * port handover.  Otherwise it might see that a full-speed device
3630	 * was gone before the EHCI controller had handed its port over to
3631	 * the companion full-speed controller.
3632	 */
3633	set_freezable();
3634
3635	do {
3636		hub_events();
3637		wait_event_freezable(khubd_wait,
3638				!list_empty(&hub_event_list) ||
3639				kthread_should_stop());
3640	} while (!kthread_should_stop() || !list_empty(&hub_event_list));
3641
3642	pr_debug("%s: khubd exiting\n", usbcore_name);
3643	return 0;
3644}
3645
3646static const struct usb_device_id hub_id_table[] = {
3647    { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
3648      .bDeviceClass = USB_CLASS_HUB},
3649    { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
3650      .bInterfaceClass = USB_CLASS_HUB},
3651    { }						/* Terminating entry */
3652};
3653
3654MODULE_DEVICE_TABLE (usb, hub_id_table);
3655
3656static struct usb_driver hub_driver = {
3657	.name =		"hub",
3658	.probe =	hub_probe,
3659	.disconnect =	hub_disconnect,
3660	.suspend =	hub_suspend,
3661	.resume =	hub_resume,
3662	.reset_resume =	hub_reset_resume,
3663	.pre_reset =	hub_pre_reset,
3664	.post_reset =	hub_post_reset,
3665	.unlocked_ioctl = hub_ioctl,
3666	.id_table =	hub_id_table,
3667	.supports_autosuspend =	1,
3668};
3669
3670int usb_hub_init(void)
3671{
3672	if (usb_register(&hub_driver) < 0) {
3673		printk(KERN_ERR "%s: can't register hub driver\n",
3674			usbcore_name);
3675		return -1;
3676	}
3677
3678	khubd_task = kthread_run(hub_thread, NULL, "khubd");
3679	if (!IS_ERR(khubd_task))
3680		return 0;
3681
3682	/* Fall through if kernel_thread failed */
3683	usb_deregister(&hub_driver);
3684	printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
3685
3686	return -1;
3687}
3688
3689void usb_hub_cleanup(void)
3690{
3691	kthread_stop(khubd_task);
3692
3693	/*
3694	 * Hub resources are freed for us by usb_deregister. It calls
3695	 * usb_driver_purge on every device which in turn calls that
3696	 * devices disconnect function if it is using this driver.
3697	 * The hub_disconnect function takes care of releasing the
3698	 * individual hub resources. -greg
3699	 */
3700	usb_deregister(&hub_driver);
3701} /* usb_hub_cleanup() */
3702
3703static int descriptors_changed(struct usb_device *udev,
3704		struct usb_device_descriptor *old_device_descriptor)
3705{
3706	int		changed = 0;
3707	unsigned	index;
3708	unsigned	serial_len = 0;
3709	unsigned	len;
3710	unsigned	old_length;
3711	int		length;
3712	char		*buf;
3713
3714	if (memcmp(&udev->descriptor, old_device_descriptor,
3715			sizeof(*old_device_descriptor)) != 0)
3716		return 1;
3717
3718	/* Since the idVendor, idProduct, and bcdDevice values in the
3719	 * device descriptor haven't changed, we will assume the
3720	 * Manufacturer and Product strings haven't changed either.
3721	 * But the SerialNumber string could be different (e.g., a
3722	 * different flash card of the same brand).
3723	 */
3724	if (udev->serial)
3725		serial_len = strlen(udev->serial) + 1;
3726
3727	len = serial_len;
3728	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
3729		old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
3730		len = max(len, old_length);
3731	}
3732
3733	buf = kmalloc(len, GFP_NOIO);
3734	if (buf == NULL) {
3735		dev_err(&udev->dev, "no mem to re-read configs after reset\n");
3736		/* assume the worst */
3737		return 1;
3738	}
3739	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
3740		old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
3741		length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
3742				old_length);
3743		if (length != old_length) {
3744			dev_dbg(&udev->dev, "config index %d, error %d\n",
3745					index, length);
3746			changed = 1;
3747			break;
3748		}
3749		if (memcmp (buf, udev->rawdescriptors[index], old_length)
3750				!= 0) {
3751			dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
3752				index,
3753				((struct usb_config_descriptor *) buf)->
3754					bConfigurationValue);
3755			changed = 1;
3756			break;
3757		}
3758	}
3759
3760	if (!changed && serial_len) {
3761		length = usb_string(udev, udev->descriptor.iSerialNumber,
3762				buf, serial_len);
3763		if (length + 1 != serial_len) {
3764			dev_dbg(&udev->dev, "serial string error %d\n",
3765					length);
3766			changed = 1;
3767		} else if (memcmp(buf, udev->serial, length) != 0) {
3768			dev_dbg(&udev->dev, "serial string changed\n");
3769			changed = 1;
3770		}
3771	}
3772
3773	kfree(buf);
3774	return changed;
3775}
3776
3777/**
3778 * usb_reset_and_verify_device - perform a USB port reset to reinitialize a device
3779 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
3780 *
3781 * WARNING - don't use this routine to reset a composite device
3782 * (one with multiple interfaces owned by separate drivers)!
3783 * Use usb_reset_device() instead.
3784 *
3785 * Do a port reset, reassign the device's address, and establish its
3786 * former operating configuration.  If the reset fails, or the device's
3787 * descriptors change from their values before the reset, or the original
3788 * configuration and altsettings cannot be restored, a flag will be set
3789 * telling khubd to pretend the device has been disconnected and then
3790 * re-connected.  All drivers will be unbound, and the device will be
3791 * re-enumerated and probed all over again.
3792 *
3793 * Returns 0 if the reset succeeded, -ENODEV if the device has been
3794 * flagged for logical disconnection, or some other negative error code
3795 * if the reset wasn't even attempted.
3796 *
3797 * The caller must own the device lock.  For example, it's safe to use
3798 * this from a driver probe() routine after downloading new firmware.
3799 * For calls that might not occur during probe(), drivers should lock
3800 * the device using usb_lock_device_for_reset().
3801 *
3802 * Locking exception: This routine may also be called from within an
3803 * autoresume handler.  Such usage won't conflict with other tasks
3804 * holding the device lock because these tasks should always call
3805 * usb_autopm_resume_device(), thereby preventing any unwanted autoresume.
3806 */
3807static int usb_reset_and_verify_device(struct usb_device *udev)
3808{
3809	struct usb_device		*parent_hdev = udev->parent;
3810	struct usb_hub			*parent_hub;
3811	struct usb_hcd			*hcd = bus_to_hcd(udev->bus);
3812	struct usb_device_descriptor	descriptor = udev->descriptor;
3813	int 				i, ret = 0;
3814	int				port1 = udev->portnum;
3815
3816	if (udev->state == USB_STATE_NOTATTACHED ||
3817			udev->state == USB_STATE_SUSPENDED) {
3818		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3819				udev->state);
3820		return -EINVAL;
3821	}
3822
3823	if (!parent_hdev) {
3824		/* this requires hcd-specific logic; see ohci_restart() */
3825		dev_dbg(&udev->dev, "%s for root hub!\n", __func__);
3826		return -EISDIR;
3827	}
3828	parent_hub = hdev_to_hub(parent_hdev);
3829
 
 
 
 
 
 
 
 
 
 
3830	set_bit(port1, parent_hub->busy_bits);
3831	for (i = 0; i < SET_CONFIG_TRIES; ++i) {
3832
3833		/* ep0 maxpacket size may change; let the HCD know about it.
3834		 * Other endpoints will be handled by re-enumeration. */
3835		usb_ep0_reinit(udev);
3836		ret = hub_port_init(parent_hub, udev, port1, i);
3837		if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
3838			break;
3839	}
3840	clear_bit(port1, parent_hub->busy_bits);
3841
3842	if (ret < 0)
3843		goto re_enumerate;
3844 
3845	/* Device might have changed firmware (DFU or similar) */
3846	if (descriptors_changed(udev, &descriptor)) {
3847		dev_info(&udev->dev, "device firmware changed\n");
3848		udev->descriptor = descriptor;	/* for disconnect() calls */
3849		goto re_enumerate;
3850  	}
3851
3852	/* Restore the device's previous configuration */
3853	if (!udev->actconfig)
3854		goto done;
3855
3856	mutex_lock(hcd->bandwidth_mutex);
3857	ret = usb_hcd_alloc_bandwidth(udev, udev->actconfig, NULL, NULL);
3858	if (ret < 0) {
3859		dev_warn(&udev->dev,
3860				"Busted HC?  Not enough HCD resources for "
3861				"old configuration.\n");
3862		mutex_unlock(hcd->bandwidth_mutex);
3863		goto re_enumerate;
3864	}
3865	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3866			USB_REQ_SET_CONFIGURATION, 0,
3867			udev->actconfig->desc.bConfigurationValue, 0,
3868			NULL, 0, USB_CTRL_SET_TIMEOUT);
3869	if (ret < 0) {
3870		dev_err(&udev->dev,
3871			"can't restore configuration #%d (error=%d)\n",
3872			udev->actconfig->desc.bConfigurationValue, ret);
3873		mutex_unlock(hcd->bandwidth_mutex);
3874		goto re_enumerate;
3875  	}
3876	mutex_unlock(hcd->bandwidth_mutex);
3877	usb_set_device_state(udev, USB_STATE_CONFIGURED);
3878
3879	/* Put interfaces back into the same altsettings as before.
3880	 * Don't bother to send the Set-Interface request for interfaces
3881	 * that were already in altsetting 0; besides being unnecessary,
3882	 * many devices can't handle it.  Instead just reset the host-side
3883	 * endpoint state.
3884	 */
3885	for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3886		struct usb_host_config *config = udev->actconfig;
3887		struct usb_interface *intf = config->interface[i];
3888		struct usb_interface_descriptor *desc;
3889
3890		desc = &intf->cur_altsetting->desc;
3891		if (desc->bAlternateSetting == 0) {
3892			usb_disable_interface(udev, intf, true);
3893			usb_enable_interface(udev, intf, true);
3894			ret = 0;
3895		} else {
3896			/* Let the bandwidth allocation function know that this
3897			 * device has been reset, and it will have to use
3898			 * alternate setting 0 as the current alternate setting.
3899			 */
3900			intf->resetting_device = 1;
3901			ret = usb_set_interface(udev, desc->bInterfaceNumber,
3902					desc->bAlternateSetting);
3903			intf->resetting_device = 0;
3904		}
3905		if (ret < 0) {
3906			dev_err(&udev->dev, "failed to restore interface %d "
3907				"altsetting %d (error=%d)\n",
3908				desc->bInterfaceNumber,
3909				desc->bAlternateSetting,
3910				ret);
3911			goto re_enumerate;
3912		}
3913	}
3914
3915done:
 
 
3916	return 0;
3917 
3918re_enumerate:
 
3919	hub_port_logical_disconnect(parent_hub, port1);
3920	return -ENODEV;
3921}
3922
3923/**
3924 * usb_reset_device - warn interface drivers and perform a USB port reset
3925 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
3926 *
3927 * Warns all drivers bound to registered interfaces (using their pre_reset
3928 * method), performs the port reset, and then lets the drivers know that
3929 * the reset is over (using their post_reset method).
3930 *
3931 * Return value is the same as for usb_reset_and_verify_device().
3932 *
3933 * The caller must own the device lock.  For example, it's safe to use
3934 * this from a driver probe() routine after downloading new firmware.
3935 * For calls that might not occur during probe(), drivers should lock
3936 * the device using usb_lock_device_for_reset().
3937 *
3938 * If an interface is currently being probed or disconnected, we assume
3939 * its driver knows how to handle resets.  For all other interfaces,
3940 * if the driver doesn't have pre_reset and post_reset methods then
3941 * we attempt to unbind it and rebind afterward.
3942 */
3943int usb_reset_device(struct usb_device *udev)
3944{
3945	int ret;
3946	int i;
3947	struct usb_host_config *config = udev->actconfig;
3948
3949	if (udev->state == USB_STATE_NOTATTACHED ||
3950			udev->state == USB_STATE_SUSPENDED) {
3951		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3952				udev->state);
3953		return -EINVAL;
3954	}
3955
3956	/* Prevent autosuspend during the reset */
3957	usb_autoresume_device(udev);
3958
3959	if (config) {
3960		for (i = 0; i < config->desc.bNumInterfaces; ++i) {
3961			struct usb_interface *cintf = config->interface[i];
3962			struct usb_driver *drv;
3963			int unbind = 0;
3964
3965			if (cintf->dev.driver) {
3966				drv = to_usb_driver(cintf->dev.driver);
3967				if (drv->pre_reset && drv->post_reset)
3968					unbind = (drv->pre_reset)(cintf);
3969				else if (cintf->condition ==
3970						USB_INTERFACE_BOUND)
3971					unbind = 1;
3972				if (unbind)
3973					usb_forced_unbind_intf(cintf);
3974			}
3975		}
3976	}
3977
3978	ret = usb_reset_and_verify_device(udev);
3979
3980	if (config) {
3981		for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
3982			struct usb_interface *cintf = config->interface[i];
3983			struct usb_driver *drv;
3984			int rebind = cintf->needs_binding;
3985
3986			if (!rebind && cintf->dev.driver) {
3987				drv = to_usb_driver(cintf->dev.driver);
3988				if (drv->post_reset)
3989					rebind = (drv->post_reset)(cintf);
3990				else if (cintf->condition ==
3991						USB_INTERFACE_BOUND)
3992					rebind = 1;
3993			}
3994			if (ret == 0 && rebind)
3995				usb_rebind_intf(cintf);
3996		}
3997	}
3998
3999	usb_autosuspend_device(udev);
4000	return ret;
4001}
4002EXPORT_SYMBOL_GPL(usb_reset_device);
4003
4004
4005/**
4006 * usb_queue_reset_device - Reset a USB device from an atomic context
4007 * @iface: USB interface belonging to the device to reset
4008 *
4009 * This function can be used to reset a USB device from an atomic
4010 * context, where usb_reset_device() won't work (as it blocks).
4011 *
4012 * Doing a reset via this method is functionally equivalent to calling
4013 * usb_reset_device(), except for the fact that it is delayed to a
4014 * workqueue. This means that any drivers bound to other interfaces
4015 * might be unbound, as well as users from usbfs in user space.
4016 *
4017 * Corner cases:
4018 *
4019 * - Scheduling two resets at the same time from two different drivers
4020 *   attached to two different interfaces of the same device is
4021 *   possible; depending on how the driver attached to each interface
4022 *   handles ->pre_reset(), the second reset might happen or not.
4023 *
4024 * - If a driver is unbound and it had a pending reset, the reset will
4025 *   be cancelled.
4026 *
4027 * - This function can be called during .probe() or .disconnect()
4028 *   times. On return from .disconnect(), any pending resets will be
4029 *   cancelled.
4030 *
4031 * There is no no need to lock/unlock the @reset_ws as schedule_work()
4032 * does its own.
4033 *
4034 * NOTE: We don't do any reference count tracking because it is not
4035 *     needed. The lifecycle of the work_struct is tied to the
4036 *     usb_interface. Before destroying the interface we cancel the
4037 *     work_struct, so the fact that work_struct is queued and or
4038 *     running means the interface (and thus, the device) exist and
4039 *     are referenced.
4040 */
4041void usb_queue_reset_device(struct usb_interface *iface)
4042{
4043	schedule_work(&iface->reset_ws);
4044}
4045EXPORT_SYMBOL_GPL(usb_queue_reset_device);
v3.5.6
   1/*
   2 * USB hub driver.
   3 *
   4 * (C) Copyright 1999 Linus Torvalds
   5 * (C) Copyright 1999 Johannes Erdfelt
   6 * (C) Copyright 1999 Gregory P. Smith
   7 * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
   8 *
   9 */
  10
  11#include <linux/kernel.h>
  12#include <linux/errno.h>
  13#include <linux/module.h>
  14#include <linux/moduleparam.h>
  15#include <linux/completion.h>
  16#include <linux/sched.h>
  17#include <linux/list.h>
  18#include <linux/slab.h>
  19#include <linux/ioctl.h>
  20#include <linux/usb.h>
  21#include <linux/usbdevice_fs.h>
  22#include <linux/usb/hcd.h>
  23#include <linux/usb/quirks.h>
  24#include <linux/kthread.h>
  25#include <linux/mutex.h>
  26#include <linux/freezer.h>
  27#include <linux/random.h>
  28
  29#include <asm/uaccess.h>
  30#include <asm/byteorder.h>
  31
  32#include "usb.h"
  33
  34/* if we are in debug mode, always announce new devices */
  35#ifdef DEBUG
  36#ifndef CONFIG_USB_ANNOUNCE_NEW_DEVICES
  37#define CONFIG_USB_ANNOUNCE_NEW_DEVICES
  38#endif
  39#endif
  40
  41struct usb_hub {
  42	struct device		*intfdev;	/* the "interface" device */
  43	struct usb_device	*hdev;
  44	struct kref		kref;
  45	struct urb		*urb;		/* for interrupt polling pipe */
  46
  47	/* buffer for urb ... with extra space in case of babble */
  48	char			(*buffer)[8];
  49	union {
  50		struct usb_hub_status	hub;
  51		struct usb_port_status	port;
  52	}			*status;	/* buffer for status reports */
  53	struct mutex		status_mutex;	/* for the status buffer */
  54
  55	int			error;		/* last reported error */
  56	int			nerrors;	/* track consecutive errors */
  57
  58	struct list_head	event_list;	/* hubs w/data or errs ready */
  59	unsigned long		event_bits[1];	/* status change bitmask */
  60	unsigned long		change_bits[1];	/* ports with logical connect
  61							status change */
  62	unsigned long		busy_bits[1];	/* ports being reset or
  63							resumed */
  64	unsigned long		removed_bits[1]; /* ports with a "removed"
  65							device present */
  66	unsigned long		wakeup_bits[1];	/* ports that have signaled
  67							remote wakeup */
  68#if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
  69#error event_bits[] is too short!
  70#endif
  71
  72	struct usb_hub_descriptor *descriptor;	/* class descriptor */
  73	struct usb_tt		tt;		/* Transaction Translator */
  74
  75	unsigned		mA_per_port;	/* current for each child */
  76
  77	unsigned		limited_power:1;
  78	unsigned		quiescing:1;
  79	unsigned		disconnected:1;
  80
  81	unsigned		has_indicators:1;
  82	u8			indicator[USB_MAXCHILDREN];
  83	struct delayed_work	leds;
  84	struct delayed_work	init_work;
  85	void			**port_owners;
  86};
  87
  88static inline int hub_is_superspeed(struct usb_device *hdev)
  89{
  90	return (hdev->descriptor.bDeviceProtocol == USB_HUB_PR_SS);
  91}
  92
  93/* Protect struct usb_device->state and ->children members
  94 * Note: Both are also protected by ->dev.sem, except that ->state can
  95 * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
  96static DEFINE_SPINLOCK(device_state_lock);
  97
  98/* khubd's worklist and its lock */
  99static DEFINE_SPINLOCK(hub_event_lock);
 100static LIST_HEAD(hub_event_list);	/* List of hubs needing servicing */
 101
 102/* Wakes up khubd */
 103static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
 104
 105static struct task_struct *khubd_task;
 106
 107/* cycle leds on hubs that aren't blinking for attention */
 108static bool blinkenlights = 0;
 109module_param (blinkenlights, bool, S_IRUGO);
 110MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
 111
 112/*
 113 * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
 114 * 10 seconds to send reply for the initial 64-byte descriptor request.
 115 */
 116/* define initial 64-byte descriptor request timeout in milliseconds */
 117static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
 118module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
 119MODULE_PARM_DESC(initial_descriptor_timeout,
 120		"initial 64-byte descriptor request timeout in milliseconds "
 121		"(default 5000 - 5.0 seconds)");
 122
 123/*
 124 * As of 2.6.10 we introduce a new USB device initialization scheme which
 125 * closely resembles the way Windows works.  Hopefully it will be compatible
 126 * with a wider range of devices than the old scheme.  However some previously
 127 * working devices may start giving rise to "device not accepting address"
 128 * errors; if that happens the user can try the old scheme by adjusting the
 129 * following module parameters.
 130 *
 131 * For maximum flexibility there are two boolean parameters to control the
 132 * hub driver's behavior.  On the first initialization attempt, if the
 133 * "old_scheme_first" parameter is set then the old scheme will be used,
 134 * otherwise the new scheme is used.  If that fails and "use_both_schemes"
 135 * is set, then the driver will make another attempt, using the other scheme.
 136 */
 137static bool old_scheme_first = 0;
 138module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
 139MODULE_PARM_DESC(old_scheme_first,
 140		 "start with the old device initialization scheme");
 141
 142static bool use_both_schemes = 1;
 143module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
 144MODULE_PARM_DESC(use_both_schemes,
 145		"try the other device initialization scheme if the "
 146		"first one fails");
 147
 148/* Mutual exclusion for EHCI CF initialization.  This interferes with
 149 * port reset on some companion controllers.
 150 */
 151DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
 152EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
 153
 154#define HUB_DEBOUNCE_TIMEOUT	1500
 155#define HUB_DEBOUNCE_STEP	  25
 156#define HUB_DEBOUNCE_STABLE	 100
 157
 158
 159static int usb_reset_and_verify_device(struct usb_device *udev);
 160
 161static inline char *portspeed(struct usb_hub *hub, int portstatus)
 162{
 163	if (hub_is_superspeed(hub->hdev))
 164		return "5.0 Gb/s";
 165	if (portstatus & USB_PORT_STAT_HIGH_SPEED)
 166    		return "480 Mb/s";
 167	else if (portstatus & USB_PORT_STAT_LOW_SPEED)
 168		return "1.5 Mb/s";
 169	else
 170		return "12 Mb/s";
 171}
 172
 173/* Note that hdev or one of its children must be locked! */
 174static struct usb_hub *hdev_to_hub(struct usb_device *hdev)
 175{
 176	if (!hdev || !hdev->actconfig)
 177		return NULL;
 178	return usb_get_intfdata(hdev->actconfig->interface[0]);
 179}
 180
 181static int usb_device_supports_lpm(struct usb_device *udev)
 182{
 183	/* USB 2.1 (and greater) devices indicate LPM support through
 184	 * their USB 2.0 Extended Capabilities BOS descriptor.
 185	 */
 186	if (udev->speed == USB_SPEED_HIGH) {
 187		if (udev->bos->ext_cap &&
 188			(USB_LPM_SUPPORT &
 189			 le32_to_cpu(udev->bos->ext_cap->bmAttributes)))
 190			return 1;
 191		return 0;
 192	}
 193
 194	/* All USB 3.0 must support LPM, but we need their max exit latency
 195	 * information from the SuperSpeed Extended Capabilities BOS descriptor.
 196	 */
 197	if (!udev->bos->ss_cap) {
 198		dev_warn(&udev->dev, "No LPM exit latency info found.  "
 199				"Power management will be impacted.\n");
 200		return 0;
 201	}
 202	if (udev->parent->lpm_capable)
 203		return 1;
 204
 205	dev_warn(&udev->dev, "Parent hub missing LPM exit latency info.  "
 206			"Power management will be impacted.\n");
 207	return 0;
 208}
 209
 210/*
 211 * Set the Maximum Exit Latency (MEL) for the host to initiate a transition from
 212 * either U1 or U2.
 213 */
 214static void usb_set_lpm_mel(struct usb_device *udev,
 215		struct usb3_lpm_parameters *udev_lpm_params,
 216		unsigned int udev_exit_latency,
 217		struct usb_hub *hub,
 218		struct usb3_lpm_parameters *hub_lpm_params,
 219		unsigned int hub_exit_latency)
 220{
 221	unsigned int total_mel;
 222	unsigned int device_mel;
 223	unsigned int hub_mel;
 224
 225	/*
 226	 * Calculate the time it takes to transition all links from the roothub
 227	 * to the parent hub into U0.  The parent hub must then decode the
 228	 * packet (hub header decode latency) to figure out which port it was
 229	 * bound for.
 230	 *
 231	 * The Hub Header decode latency is expressed in 0.1us intervals (0x1
 232	 * means 0.1us).  Multiply that by 100 to get nanoseconds.
 233	 */
 234	total_mel = hub_lpm_params->mel +
 235		(hub->descriptor->u.ss.bHubHdrDecLat * 100);
 236
 237	/*
 238	 * How long will it take to transition the downstream hub's port into
 239	 * U0?  The greater of either the hub exit latency or the device exit
 240	 * latency.
 241	 *
 242	 * The BOS U1/U2 exit latencies are expressed in 1us intervals.
 243	 * Multiply that by 1000 to get nanoseconds.
 244	 */
 245	device_mel = udev_exit_latency * 1000;
 246	hub_mel = hub_exit_latency * 1000;
 247	if (device_mel > hub_mel)
 248		total_mel += device_mel;
 249	else
 250		total_mel += hub_mel;
 251
 252	udev_lpm_params->mel = total_mel;
 253}
 254
 255/*
 256 * Set the maximum Device to Host Exit Latency (PEL) for the device to initiate
 257 * a transition from either U1 or U2.
 258 */
 259static void usb_set_lpm_pel(struct usb_device *udev,
 260		struct usb3_lpm_parameters *udev_lpm_params,
 261		unsigned int udev_exit_latency,
 262		struct usb_hub *hub,
 263		struct usb3_lpm_parameters *hub_lpm_params,
 264		unsigned int hub_exit_latency,
 265		unsigned int port_to_port_exit_latency)
 266{
 267	unsigned int first_link_pel;
 268	unsigned int hub_pel;
 269
 270	/*
 271	 * First, the device sends an LFPS to transition the link between the
 272	 * device and the parent hub into U0.  The exit latency is the bigger of
 273	 * the device exit latency or the hub exit latency.
 274	 */
 275	if (udev_exit_latency > hub_exit_latency)
 276		first_link_pel = udev_exit_latency * 1000;
 277	else
 278		first_link_pel = hub_exit_latency * 1000;
 279
 280	/*
 281	 * When the hub starts to receive the LFPS, there is a slight delay for
 282	 * it to figure out that one of the ports is sending an LFPS.  Then it
 283	 * will forward the LFPS to its upstream link.  The exit latency is the
 284	 * delay, plus the PEL that we calculated for this hub.
 285	 */
 286	hub_pel = port_to_port_exit_latency * 1000 + hub_lpm_params->pel;
 287
 288	/*
 289	 * According to figure C-7 in the USB 3.0 spec, the PEL for this device
 290	 * is the greater of the two exit latencies.
 291	 */
 292	if (first_link_pel > hub_pel)
 293		udev_lpm_params->pel = first_link_pel;
 294	else
 295		udev_lpm_params->pel = hub_pel;
 296}
 297
 298/*
 299 * Set the System Exit Latency (SEL) to indicate the total worst-case time from
 300 * when a device initiates a transition to U0, until when it will receive the
 301 * first packet from the host controller.
 302 *
 303 * Section C.1.5.1 describes the four components to this:
 304 *  - t1: device PEL
 305 *  - t2: time for the ERDY to make it from the device to the host.
 306 *  - t3: a host-specific delay to process the ERDY.
 307 *  - t4: time for the packet to make it from the host to the device.
 308 *
 309 * t3 is specific to both the xHCI host and the platform the host is integrated
 310 * into.  The Intel HW folks have said it's negligible, FIXME if a different
 311 * vendor says otherwise.
 312 */
 313static void usb_set_lpm_sel(struct usb_device *udev,
 314		struct usb3_lpm_parameters *udev_lpm_params)
 315{
 316	struct usb_device *parent;
 317	unsigned int num_hubs;
 318	unsigned int total_sel;
 319
 320	/* t1 = device PEL */
 321	total_sel = udev_lpm_params->pel;
 322	/* How many external hubs are in between the device & the root port. */
 323	for (parent = udev->parent, num_hubs = 0; parent->parent;
 324			parent = parent->parent)
 325		num_hubs++;
 326	/* t2 = 2.1us + 250ns * (num_hubs - 1) */
 327	if (num_hubs > 0)
 328		total_sel += 2100 + 250 * (num_hubs - 1);
 329
 330	/* t4 = 250ns * num_hubs */
 331	total_sel += 250 * num_hubs;
 332
 333	udev_lpm_params->sel = total_sel;
 334}
 335
 336static void usb_set_lpm_parameters(struct usb_device *udev)
 337{
 338	struct usb_hub *hub;
 339	unsigned int port_to_port_delay;
 340	unsigned int udev_u1_del;
 341	unsigned int udev_u2_del;
 342	unsigned int hub_u1_del;
 343	unsigned int hub_u2_del;
 344
 345	if (!udev->lpm_capable || udev->speed != USB_SPEED_SUPER)
 346		return;
 347
 348	hub = hdev_to_hub(udev->parent);
 349	/* It doesn't take time to transition the roothub into U0, since it
 350	 * doesn't have an upstream link.
 351	 */
 352	if (!hub)
 353		return;
 354
 355	udev_u1_del = udev->bos->ss_cap->bU1devExitLat;
 356	udev_u2_del = udev->bos->ss_cap->bU2DevExitLat;
 357	hub_u1_del = udev->parent->bos->ss_cap->bU1devExitLat;
 358	hub_u2_del = udev->parent->bos->ss_cap->bU2DevExitLat;
 359
 360	usb_set_lpm_mel(udev, &udev->u1_params, udev_u1_del,
 361			hub, &udev->parent->u1_params, hub_u1_del);
 362
 363	usb_set_lpm_mel(udev, &udev->u2_params, udev_u2_del,
 364			hub, &udev->parent->u2_params, hub_u2_del);
 365
 366	/*
 367	 * Appendix C, section C.2.2.2, says that there is a slight delay from
 368	 * when the parent hub notices the downstream port is trying to
 369	 * transition to U0 to when the hub initiates a U0 transition on its
 370	 * upstream port.  The section says the delays are tPort2PortU1EL and
 371	 * tPort2PortU2EL, but it doesn't define what they are.
 372	 *
 373	 * The hub chapter, sections 10.4.2.4 and 10.4.2.5 seem to be talking
 374	 * about the same delays.  Use the maximum delay calculations from those
 375	 * sections.  For U1, it's tHubPort2PortExitLat, which is 1us max.  For
 376	 * U2, it's tHubPort2PortExitLat + U2DevExitLat - U1DevExitLat.  I
 377	 * assume the device exit latencies they are talking about are the hub
 378	 * exit latencies.
 379	 *
 380	 * What do we do if the U2 exit latency is less than the U1 exit
 381	 * latency?  It's possible, although not likely...
 382	 */
 383	port_to_port_delay = 1;
 384
 385	usb_set_lpm_pel(udev, &udev->u1_params, udev_u1_del,
 386			hub, &udev->parent->u1_params, hub_u1_del,
 387			port_to_port_delay);
 388
 389	if (hub_u2_del > hub_u1_del)
 390		port_to_port_delay = 1 + hub_u2_del - hub_u1_del;
 391	else
 392		port_to_port_delay = 1 + hub_u1_del;
 393
 394	usb_set_lpm_pel(udev, &udev->u2_params, udev_u2_del,
 395			hub, &udev->parent->u2_params, hub_u2_del,
 396			port_to_port_delay);
 397
 398	/* Now that we've got PEL, calculate SEL. */
 399	usb_set_lpm_sel(udev, &udev->u1_params);
 400	usb_set_lpm_sel(udev, &udev->u2_params);
 401}
 402
 403/* USB 2.0 spec Section 11.24.4.5 */
 404static int get_hub_descriptor(struct usb_device *hdev, void *data)
 405{
 406	int i, ret, size;
 407	unsigned dtype;
 408
 409	if (hub_is_superspeed(hdev)) {
 410		dtype = USB_DT_SS_HUB;
 411		size = USB_DT_SS_HUB_SIZE;
 412	} else {
 413		dtype = USB_DT_HUB;
 414		size = sizeof(struct usb_hub_descriptor);
 415	}
 416
 417	for (i = 0; i < 3; i++) {
 418		ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 419			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
 420			dtype << 8, 0, data, size,
 421			USB_CTRL_GET_TIMEOUT);
 422		if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
 423			return ret;
 424	}
 425	return -EINVAL;
 426}
 427
 428/*
 429 * USB 2.0 spec Section 11.24.2.1
 430 */
 431static int clear_hub_feature(struct usb_device *hdev, int feature)
 432{
 433	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 434		USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
 435}
 436
 437/*
 438 * USB 2.0 spec Section 11.24.2.2
 439 */
 440static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
 441{
 442	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 443		USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
 444		NULL, 0, 1000);
 445}
 446
 447/*
 448 * USB 2.0 spec Section 11.24.2.13
 449 */
 450static int set_port_feature(struct usb_device *hdev, int port1, int feature)
 451{
 452	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 453		USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
 454		NULL, 0, 1000);
 455}
 456
 457/*
 458 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
 459 * for info about using port indicators
 460 */
 461static void set_port_led(
 462	struct usb_hub *hub,
 463	int port1,
 464	int selector
 465)
 466{
 467	int status = set_port_feature(hub->hdev, (selector << 8) | port1,
 468			USB_PORT_FEAT_INDICATOR);
 469	if (status < 0)
 470		dev_dbg (hub->intfdev,
 471			"port %d indicator %s status %d\n",
 472			port1,
 473			({ char *s; switch (selector) {
 474			case HUB_LED_AMBER: s = "amber"; break;
 475			case HUB_LED_GREEN: s = "green"; break;
 476			case HUB_LED_OFF: s = "off"; break;
 477			case HUB_LED_AUTO: s = "auto"; break;
 478			default: s = "??"; break;
 479			}; s; }),
 480			status);
 481}
 482
 483#define	LED_CYCLE_PERIOD	((2*HZ)/3)
 484
 485static void led_work (struct work_struct *work)
 486{
 487	struct usb_hub		*hub =
 488		container_of(work, struct usb_hub, leds.work);
 489	struct usb_device	*hdev = hub->hdev;
 490	unsigned		i;
 491	unsigned		changed = 0;
 492	int			cursor = -1;
 493
 494	if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
 495		return;
 496
 497	for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
 498		unsigned	selector, mode;
 499
 500		/* 30%-50% duty cycle */
 501
 502		switch (hub->indicator[i]) {
 503		/* cycle marker */
 504		case INDICATOR_CYCLE:
 505			cursor = i;
 506			selector = HUB_LED_AUTO;
 507			mode = INDICATOR_AUTO;
 508			break;
 509		/* blinking green = sw attention */
 510		case INDICATOR_GREEN_BLINK:
 511			selector = HUB_LED_GREEN;
 512			mode = INDICATOR_GREEN_BLINK_OFF;
 513			break;
 514		case INDICATOR_GREEN_BLINK_OFF:
 515			selector = HUB_LED_OFF;
 516			mode = INDICATOR_GREEN_BLINK;
 517			break;
 518		/* blinking amber = hw attention */
 519		case INDICATOR_AMBER_BLINK:
 520			selector = HUB_LED_AMBER;
 521			mode = INDICATOR_AMBER_BLINK_OFF;
 522			break;
 523		case INDICATOR_AMBER_BLINK_OFF:
 524			selector = HUB_LED_OFF;
 525			mode = INDICATOR_AMBER_BLINK;
 526			break;
 527		/* blink green/amber = reserved */
 528		case INDICATOR_ALT_BLINK:
 529			selector = HUB_LED_GREEN;
 530			mode = INDICATOR_ALT_BLINK_OFF;
 531			break;
 532		case INDICATOR_ALT_BLINK_OFF:
 533			selector = HUB_LED_AMBER;
 534			mode = INDICATOR_ALT_BLINK;
 535			break;
 536		default:
 537			continue;
 538		}
 539		if (selector != HUB_LED_AUTO)
 540			changed = 1;
 541		set_port_led(hub, i + 1, selector);
 542		hub->indicator[i] = mode;
 543	}
 544	if (!changed && blinkenlights) {
 545		cursor++;
 546		cursor %= hub->descriptor->bNbrPorts;
 547		set_port_led(hub, cursor + 1, HUB_LED_GREEN);
 548		hub->indicator[cursor] = INDICATOR_CYCLE;
 549		changed++;
 550	}
 551	if (changed)
 552		schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 553}
 554
 555/* use a short timeout for hub/port status fetches */
 556#define	USB_STS_TIMEOUT		1000
 557#define	USB_STS_RETRIES		5
 558
 559/*
 560 * USB 2.0 spec Section 11.24.2.6
 561 */
 562static int get_hub_status(struct usb_device *hdev,
 563		struct usb_hub_status *data)
 564{
 565	int i, status = -ETIMEDOUT;
 566
 567	for (i = 0; i < USB_STS_RETRIES &&
 568			(status == -ETIMEDOUT || status == -EPIPE); i++) {
 569		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 570			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
 571			data, sizeof(*data), USB_STS_TIMEOUT);
 572	}
 573	return status;
 574}
 575
 576/*
 577 * USB 2.0 spec Section 11.24.2.7
 578 */
 579static int get_port_status(struct usb_device *hdev, int port1,
 580		struct usb_port_status *data)
 581{
 582	int i, status = -ETIMEDOUT;
 583
 584	for (i = 0; i < USB_STS_RETRIES &&
 585			(status == -ETIMEDOUT || status == -EPIPE); i++) {
 586		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 587			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
 588			data, sizeof(*data), USB_STS_TIMEOUT);
 589	}
 590	return status;
 591}
 592
 593static int hub_port_status(struct usb_hub *hub, int port1,
 594		u16 *status, u16 *change)
 595{
 596	int ret;
 597
 598	mutex_lock(&hub->status_mutex);
 599	ret = get_port_status(hub->hdev, port1, &hub->status->port);
 600	if (ret < 4) {
 601		dev_err(hub->intfdev,
 602			"%s failed (err = %d)\n", __func__, ret);
 603		if (ret >= 0)
 604			ret = -EIO;
 605	} else {
 606		*status = le16_to_cpu(hub->status->port.wPortStatus);
 607		*change = le16_to_cpu(hub->status->port.wPortChange);
 608
 609		ret = 0;
 610	}
 611	mutex_unlock(&hub->status_mutex);
 612	return ret;
 613}
 614
 615static void kick_khubd(struct usb_hub *hub)
 616{
 617	unsigned long	flags;
 618
 619	spin_lock_irqsave(&hub_event_lock, flags);
 620	if (!hub->disconnected && list_empty(&hub->event_list)) {
 621		list_add_tail(&hub->event_list, &hub_event_list);
 622
 623		/* Suppress autosuspend until khubd runs */
 624		usb_autopm_get_interface_no_resume(
 625				to_usb_interface(hub->intfdev));
 626		wake_up(&khubd_wait);
 627	}
 628	spin_unlock_irqrestore(&hub_event_lock, flags);
 629}
 630
 631void usb_kick_khubd(struct usb_device *hdev)
 632{
 633	struct usb_hub *hub = hdev_to_hub(hdev);
 634
 635	if (hub)
 636		kick_khubd(hub);
 637}
 638
 639/*
 640 * Let the USB core know that a USB 3.0 device has sent a Function Wake Device
 641 * Notification, which indicates it had initiated remote wakeup.
 642 *
 643 * USB 3.0 hubs do not report the port link state change from U3 to U0 when the
 644 * device initiates resume, so the USB core will not receive notice of the
 645 * resume through the normal hub interrupt URB.
 646 */
 647void usb_wakeup_notification(struct usb_device *hdev,
 648		unsigned int portnum)
 649{
 650	struct usb_hub *hub;
 651
 652	if (!hdev)
 653		return;
 654
 655	hub = hdev_to_hub(hdev);
 656	if (hub) {
 657		set_bit(portnum, hub->wakeup_bits);
 658		kick_khubd(hub);
 659	}
 660}
 661EXPORT_SYMBOL_GPL(usb_wakeup_notification);
 662
 663/* completion function, fires on port status changes and various faults */
 664static void hub_irq(struct urb *urb)
 665{
 666	struct usb_hub *hub = urb->context;
 667	int status = urb->status;
 668	unsigned i;
 669	unsigned long bits;
 670
 671	switch (status) {
 672	case -ENOENT:		/* synchronous unlink */
 673	case -ECONNRESET:	/* async unlink */
 674	case -ESHUTDOWN:	/* hardware going away */
 675		return;
 676
 677	default:		/* presumably an error */
 678		/* Cause a hub reset after 10 consecutive errors */
 679		dev_dbg (hub->intfdev, "transfer --> %d\n", status);
 680		if ((++hub->nerrors < 10) || hub->error)
 681			goto resubmit;
 682		hub->error = status;
 683		/* FALL THROUGH */
 684
 685	/* let khubd handle things */
 686	case 0:			/* we got data:  port status changed */
 687		bits = 0;
 688		for (i = 0; i < urb->actual_length; ++i)
 689			bits |= ((unsigned long) ((*hub->buffer)[i]))
 690					<< (i*8);
 691		hub->event_bits[0] = bits;
 692		break;
 693	}
 694
 695	hub->nerrors = 0;
 696
 697	/* Something happened, let khubd figure it out */
 698	kick_khubd(hub);
 699
 700resubmit:
 701	if (hub->quiescing)
 702		return;
 703
 704	if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
 705			&& status != -ENODEV && status != -EPERM)
 706		dev_err (hub->intfdev, "resubmit --> %d\n", status);
 707}
 708
 709/* USB 2.0 spec Section 11.24.2.3 */
 710static inline int
 711hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
 712{
 713	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 714			       HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
 715			       tt, NULL, 0, 1000);
 716}
 717
 718/*
 719 * enumeration blocks khubd for a long time. we use keventd instead, since
 720 * long blocking there is the exception, not the rule.  accordingly, HCDs
 721 * talking to TTs must queue control transfers (not just bulk and iso), so
 722 * both can talk to the same hub concurrently.
 723 */
 724static void hub_tt_work(struct work_struct *work)
 725{
 726	struct usb_hub		*hub =
 727		container_of(work, struct usb_hub, tt.clear_work);
 728	unsigned long		flags;
 729	int			limit = 100;
 730
 731	spin_lock_irqsave (&hub->tt.lock, flags);
 732	while (--limit && !list_empty (&hub->tt.clear_list)) {
 733		struct list_head	*next;
 734		struct usb_tt_clear	*clear;
 735		struct usb_device	*hdev = hub->hdev;
 736		const struct hc_driver	*drv;
 737		int			status;
 738
 739		next = hub->tt.clear_list.next;
 740		clear = list_entry (next, struct usb_tt_clear, clear_list);
 741		list_del (&clear->clear_list);
 742
 743		/* drop lock so HCD can concurrently report other TT errors */
 744		spin_unlock_irqrestore (&hub->tt.lock, flags);
 745		status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
 746		if (status)
 747			dev_err (&hdev->dev,
 748				"clear tt %d (%04x) error %d\n",
 749				clear->tt, clear->devinfo, status);
 750
 751		/* Tell the HCD, even if the operation failed */
 752		drv = clear->hcd->driver;
 753		if (drv->clear_tt_buffer_complete)
 754			(drv->clear_tt_buffer_complete)(clear->hcd, clear->ep);
 755
 756		kfree(clear);
 757		spin_lock_irqsave(&hub->tt.lock, flags);
 758	}
 759	spin_unlock_irqrestore (&hub->tt.lock, flags);
 760}
 761
 762/**
 763 * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
 764 * @urb: an URB associated with the failed or incomplete split transaction
 765 *
 766 * High speed HCDs use this to tell the hub driver that some split control or
 767 * bulk transaction failed in a way that requires clearing internal state of
 768 * a transaction translator.  This is normally detected (and reported) from
 769 * interrupt context.
 770 *
 771 * It may not be possible for that hub to handle additional full (or low)
 772 * speed transactions until that state is fully cleared out.
 773 */
 774int usb_hub_clear_tt_buffer(struct urb *urb)
 775{
 776	struct usb_device	*udev = urb->dev;
 777	int			pipe = urb->pipe;
 778	struct usb_tt		*tt = udev->tt;
 779	unsigned long		flags;
 780	struct usb_tt_clear	*clear;
 781
 782	/* we've got to cope with an arbitrary number of pending TT clears,
 783	 * since each TT has "at least two" buffers that can need it (and
 784	 * there can be many TTs per hub).  even if they're uncommon.
 785	 */
 786	if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) {
 787		dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
 788		/* FIXME recover somehow ... RESET_TT? */
 789		return -ENOMEM;
 790	}
 791
 792	/* info that CLEAR_TT_BUFFER needs */
 793	clear->tt = tt->multi ? udev->ttport : 1;
 794	clear->devinfo = usb_pipeendpoint (pipe);
 795	clear->devinfo |= udev->devnum << 4;
 796	clear->devinfo |= usb_pipecontrol (pipe)
 797			? (USB_ENDPOINT_XFER_CONTROL << 11)
 798			: (USB_ENDPOINT_XFER_BULK << 11);
 799	if (usb_pipein (pipe))
 800		clear->devinfo |= 1 << 15;
 801
 802	/* info for completion callback */
 803	clear->hcd = bus_to_hcd(udev->bus);
 804	clear->ep = urb->ep;
 805
 806	/* tell keventd to clear state for this TT */
 807	spin_lock_irqsave (&tt->lock, flags);
 808	list_add_tail (&clear->clear_list, &tt->clear_list);
 809	schedule_work(&tt->clear_work);
 810	spin_unlock_irqrestore (&tt->lock, flags);
 811	return 0;
 812}
 813EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer);
 814
 815/* If do_delay is false, return the number of milliseconds the caller
 816 * needs to delay.
 817 */
 818static unsigned hub_power_on(struct usb_hub *hub, bool do_delay)
 819{
 820	int port1;
 821	unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
 822	unsigned delay;
 823	u16 wHubCharacteristics =
 824			le16_to_cpu(hub->descriptor->wHubCharacteristics);
 825
 826	/* Enable power on each port.  Some hubs have reserved values
 827	 * of LPSM (> 2) in their descriptors, even though they are
 828	 * USB 2.0 hubs.  Some hubs do not implement port-power switching
 829	 * but only emulate it.  In all cases, the ports won't work
 830	 * unless we send these messages to the hub.
 831	 */
 832	if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
 833		dev_dbg(hub->intfdev, "enabling power on all ports\n");
 834	else
 835		dev_dbg(hub->intfdev, "trying to enable port power on "
 836				"non-switchable hub\n");
 837	for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
 838		set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
 839
 840	/* Wait at least 100 msec for power to become stable */
 841	delay = max(pgood_delay, (unsigned) 100);
 842	if (do_delay)
 843		msleep(delay);
 844	return delay;
 845}
 846
 847static int hub_hub_status(struct usb_hub *hub,
 848		u16 *status, u16 *change)
 849{
 850	int ret;
 851
 852	mutex_lock(&hub->status_mutex);
 853	ret = get_hub_status(hub->hdev, &hub->status->hub);
 854	if (ret < 0)
 855		dev_err (hub->intfdev,
 856			"%s failed (err = %d)\n", __func__, ret);
 857	else {
 858		*status = le16_to_cpu(hub->status->hub.wHubStatus);
 859		*change = le16_to_cpu(hub->status->hub.wHubChange); 
 860		ret = 0;
 861	}
 862	mutex_unlock(&hub->status_mutex);
 863	return ret;
 864}
 865
 866static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
 867{
 868	struct usb_device *hdev = hub->hdev;
 869	int ret = 0;
 870
 871	if (hdev->children[port1-1] && set_state)
 872		usb_set_device_state(hdev->children[port1-1],
 873				USB_STATE_NOTATTACHED);
 874	if (!hub->error && !hub_is_superspeed(hub->hdev))
 875		ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
 876	if (ret)
 877		dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
 878				port1, ret);
 879	return ret;
 880}
 881
 882/*
 883 * Disable a port and mark a logical connect-change event, so that some
 884 * time later khubd will disconnect() any existing usb_device on the port
 885 * and will re-enumerate if there actually is a device attached.
 886 */
 887static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
 888{
 889	dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
 890	hub_port_disable(hub, port1, 1);
 891
 892	/* FIXME let caller ask to power down the port:
 893	 *  - some devices won't enumerate without a VBUS power cycle
 894	 *  - SRP saves power that way
 895	 *  - ... new call, TBD ...
 896	 * That's easy if this hub can switch power per-port, and
 897	 * khubd reactivates the port later (timer, SRP, etc).
 898	 * Powerdown must be optional, because of reset/DFU.
 899	 */
 900
 901	set_bit(port1, hub->change_bits);
 902 	kick_khubd(hub);
 903}
 904
 905/**
 906 * usb_remove_device - disable a device's port on its parent hub
 907 * @udev: device to be disabled and removed
 908 * Context: @udev locked, must be able to sleep.
 909 *
 910 * After @udev's port has been disabled, khubd is notified and it will
 911 * see that the device has been disconnected.  When the device is
 912 * physically unplugged and something is plugged in, the events will
 913 * be received and processed normally.
 914 */
 915int usb_remove_device(struct usb_device *udev)
 916{
 917	struct usb_hub *hub;
 918	struct usb_interface *intf;
 919
 920	if (!udev->parent)	/* Can't remove a root hub */
 921		return -EINVAL;
 922	hub = hdev_to_hub(udev->parent);
 923	intf = to_usb_interface(hub->intfdev);
 924
 925	usb_autopm_get_interface(intf);
 926	set_bit(udev->portnum, hub->removed_bits);
 927	hub_port_logical_disconnect(hub, udev->portnum);
 928	usb_autopm_put_interface(intf);
 929	return 0;
 930}
 931
 932enum hub_activation_type {
 933	HUB_INIT, HUB_INIT2, HUB_INIT3,		/* INITs must come first */
 934	HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
 935};
 936
 937static void hub_init_func2(struct work_struct *ws);
 938static void hub_init_func3(struct work_struct *ws);
 939
 940static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
 941{
 942	struct usb_device *hdev = hub->hdev;
 943	struct usb_hcd *hcd;
 944	int ret;
 945	int port1;
 946	int status;
 947	bool need_debounce_delay = false;
 948	unsigned delay;
 949
 950	/* Continue a partial initialization */
 951	if (type == HUB_INIT2)
 952		goto init2;
 953	if (type == HUB_INIT3)
 954		goto init3;
 955
 956	/* The superspeed hub except for root hub has to use Hub Depth
 957	 * value as an offset into the route string to locate the bits
 958	 * it uses to determine the downstream port number. So hub driver
 959	 * should send a set hub depth request to superspeed hub after
 960	 * the superspeed hub is set configuration in initialization or
 961	 * reset procedure.
 962	 *
 963	 * After a resume, port power should still be on.
 964	 * For any other type of activation, turn it on.
 965	 */
 966	if (type != HUB_RESUME) {
 967		if (hdev->parent && hub_is_superspeed(hdev)) {
 968			ret = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 969					HUB_SET_DEPTH, USB_RT_HUB,
 970					hdev->level - 1, 0, NULL, 0,
 971					USB_CTRL_SET_TIMEOUT);
 972			if (ret < 0)
 973				dev_err(hub->intfdev,
 974						"set hub depth failed\n");
 975		}
 976
 977		/* Speed up system boot by using a delayed_work for the
 978		 * hub's initial power-up delays.  This is pretty awkward
 979		 * and the implementation looks like a home-brewed sort of
 980		 * setjmp/longjmp, but it saves at least 100 ms for each
 981		 * root hub (assuming usbcore is compiled into the kernel
 982		 * rather than as a module).  It adds up.
 983		 *
 984		 * This can't be done for HUB_RESUME or HUB_RESET_RESUME
 985		 * because for those activation types the ports have to be
 986		 * operational when we return.  In theory this could be done
 987		 * for HUB_POST_RESET, but it's easier not to.
 988		 */
 989		if (type == HUB_INIT) {
 990			delay = hub_power_on(hub, false);
 991			PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func2);
 992			schedule_delayed_work(&hub->init_work,
 993					msecs_to_jiffies(delay));
 994
 995			/* Suppress autosuspend until init is done */
 996			usb_autopm_get_interface_no_resume(
 997					to_usb_interface(hub->intfdev));
 998			return;		/* Continues at init2: below */
 999		} else if (type == HUB_RESET_RESUME) {
1000			/* The internal host controller state for the hub device
1001			 * may be gone after a host power loss on system resume.
1002			 * Update the device's info so the HW knows it's a hub.
1003			 */
1004			hcd = bus_to_hcd(hdev->bus);
1005			if (hcd->driver->update_hub_device) {
1006				ret = hcd->driver->update_hub_device(hcd, hdev,
1007						&hub->tt, GFP_NOIO);
1008				if (ret < 0) {
1009					dev_err(hub->intfdev, "Host not "
1010							"accepting hub info "
1011							"update.\n");
1012					dev_err(hub->intfdev, "LS/FS devices "
1013							"and hubs may not work "
1014							"under this hub\n.");
1015				}
1016			}
1017			hub_power_on(hub, true);
1018		} else {
1019			hub_power_on(hub, true);
1020		}
1021	}
1022 init2:
1023
1024	/* Check each port and set hub->change_bits to let khubd know
1025	 * which ports need attention.
1026	 */
1027	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
1028		struct usb_device *udev = hdev->children[port1-1];
1029		u16 portstatus, portchange;
1030
1031		portstatus = portchange = 0;
1032		status = hub_port_status(hub, port1, &portstatus, &portchange);
1033		if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
1034			dev_dbg(hub->intfdev,
1035					"port %d: status %04x change %04x\n",
1036					port1, portstatus, portchange);
1037
1038		/* After anything other than HUB_RESUME (i.e., initialization
1039		 * or any sort of reset), every port should be disabled.
1040		 * Unconnected ports should likewise be disabled (paranoia),
1041		 * and so should ports for which we have no usb_device.
1042		 */
1043		if ((portstatus & USB_PORT_STAT_ENABLE) && (
1044				type != HUB_RESUME ||
1045				!(portstatus & USB_PORT_STAT_CONNECTION) ||
1046				!udev ||
1047				udev->state == USB_STATE_NOTATTACHED)) {
1048			/*
1049			 * USB3 protocol ports will automatically transition
1050			 * to Enabled state when detect an USB3.0 device attach.
1051			 * Do not disable USB3 protocol ports.
1052			 */
1053			if (!hub_is_superspeed(hdev)) {
1054				clear_port_feature(hdev, port1,
1055						   USB_PORT_FEAT_ENABLE);
1056				portstatus &= ~USB_PORT_STAT_ENABLE;
1057			} else {
1058				/* Pretend that power was lost for USB3 devs */
1059				portstatus &= ~USB_PORT_STAT_ENABLE;
1060			}
1061		}
1062
1063		/* Clear status-change flags; we'll debounce later */
1064		if (portchange & USB_PORT_STAT_C_CONNECTION) {
1065			need_debounce_delay = true;
1066			clear_port_feature(hub->hdev, port1,
1067					USB_PORT_FEAT_C_CONNECTION);
1068		}
1069		if (portchange & USB_PORT_STAT_C_ENABLE) {
1070			need_debounce_delay = true;
1071			clear_port_feature(hub->hdev, port1,
1072					USB_PORT_FEAT_C_ENABLE);
1073		}
1074		if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
1075				hub_is_superspeed(hub->hdev)) {
1076			need_debounce_delay = true;
1077			clear_port_feature(hub->hdev, port1,
1078					USB_PORT_FEAT_C_BH_PORT_RESET);
1079		}
 
1080		/* We can forget about a "removed" device when there's a
1081		 * physical disconnect or the connect status changes.
1082		 */
1083		if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
1084				(portchange & USB_PORT_STAT_C_CONNECTION))
1085			clear_bit(port1, hub->removed_bits);
1086
1087		if (!udev || udev->state == USB_STATE_NOTATTACHED) {
1088			/* Tell khubd to disconnect the device or
1089			 * check for a new connection
1090			 */
1091			if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
1092				set_bit(port1, hub->change_bits);
1093
1094		} else if (portstatus & USB_PORT_STAT_ENABLE) {
1095			bool port_resumed = (portstatus &
1096					USB_PORT_STAT_LINK_STATE) ==
1097				USB_SS_PORT_LS_U0;
1098			/* The power session apparently survived the resume.
1099			 * If there was an overcurrent or suspend change
1100			 * (i.e., remote wakeup request), have khubd
1101			 * take care of it.  Look at the port link state
1102			 * for USB 3.0 hubs, since they don't have a suspend
1103			 * change bit, and they don't set the port link change
1104			 * bit on device-initiated resume.
1105			 */
1106			if (portchange || (hub_is_superspeed(hub->hdev) &&
1107						port_resumed))
1108				set_bit(port1, hub->change_bits);
1109
1110		} else if (udev->persist_enabled) {
1111#ifdef CONFIG_PM
1112			udev->reset_resume = 1;
1113#endif
1114			set_bit(port1, hub->change_bits);
1115
1116		} else {
1117			/* The power session is gone; tell khubd */
1118			usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1119			set_bit(port1, hub->change_bits);
1120		}
1121	}
1122
1123	/* If no port-status-change flags were set, we don't need any
1124	 * debouncing.  If flags were set we can try to debounce the
1125	 * ports all at once right now, instead of letting khubd do them
1126	 * one at a time later on.
1127	 *
1128	 * If any port-status changes do occur during this delay, khubd
1129	 * will see them later and handle them normally.
1130	 */
1131	if (need_debounce_delay) {
1132		delay = HUB_DEBOUNCE_STABLE;
1133
1134		/* Don't do a long sleep inside a workqueue routine */
1135		if (type == HUB_INIT2) {
1136			PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func3);
1137			schedule_delayed_work(&hub->init_work,
1138					msecs_to_jiffies(delay));
1139			return;		/* Continues at init3: below */
1140		} else {
1141			msleep(delay);
1142		}
1143	}
1144 init3:
1145	hub->quiescing = 0;
1146
1147	status = usb_submit_urb(hub->urb, GFP_NOIO);
1148	if (status < 0)
1149		dev_err(hub->intfdev, "activate --> %d\n", status);
1150	if (hub->has_indicators && blinkenlights)
1151		schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
1152
1153	/* Scan all ports that need attention */
1154	kick_khubd(hub);
1155
1156	/* Allow autosuspend if it was suppressed */
1157	if (type <= HUB_INIT3)
1158		usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
1159}
1160
1161/* Implement the continuations for the delays above */
1162static void hub_init_func2(struct work_struct *ws)
1163{
1164	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1165
1166	hub_activate(hub, HUB_INIT2);
1167}
1168
1169static void hub_init_func3(struct work_struct *ws)
1170{
1171	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1172
1173	hub_activate(hub, HUB_INIT3);
1174}
1175
1176enum hub_quiescing_type {
1177	HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
1178};
1179
1180static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
1181{
1182	struct usb_device *hdev = hub->hdev;
1183	int i;
1184
1185	cancel_delayed_work_sync(&hub->init_work);
1186
1187	/* khubd and related activity won't re-trigger */
1188	hub->quiescing = 1;
1189
1190	if (type != HUB_SUSPEND) {
1191		/* Disconnect all the children */
1192		for (i = 0; i < hdev->maxchild; ++i) {
1193			if (hdev->children[i])
1194				usb_disconnect(&hdev->children[i]);
1195		}
1196	}
1197
1198	/* Stop khubd and related activity */
1199	usb_kill_urb(hub->urb);
1200	if (hub->has_indicators)
1201		cancel_delayed_work_sync(&hub->leds);
1202	if (hub->tt.hub)
1203		cancel_work_sync(&hub->tt.clear_work);
1204}
1205
1206/* caller has locked the hub device */
1207static int hub_pre_reset(struct usb_interface *intf)
1208{
1209	struct usb_hub *hub = usb_get_intfdata(intf);
1210
1211	hub_quiesce(hub, HUB_PRE_RESET);
1212	return 0;
1213}
1214
1215/* caller has locked the hub device */
1216static int hub_post_reset(struct usb_interface *intf)
1217{
1218	struct usb_hub *hub = usb_get_intfdata(intf);
1219
1220	hub_activate(hub, HUB_POST_RESET);
1221	return 0;
1222}
1223
1224static int hub_configure(struct usb_hub *hub,
1225	struct usb_endpoint_descriptor *endpoint)
1226{
1227	struct usb_hcd *hcd;
1228	struct usb_device *hdev = hub->hdev;
1229	struct device *hub_dev = hub->intfdev;
1230	u16 hubstatus, hubchange;
1231	u16 wHubCharacteristics;
1232	unsigned int pipe;
1233	int maxp, ret;
1234	char *message = "out of memory";
1235
1236	hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
1237	if (!hub->buffer) {
1238		ret = -ENOMEM;
1239		goto fail;
1240	}
1241
1242	hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
1243	if (!hub->status) {
1244		ret = -ENOMEM;
1245		goto fail;
1246	}
1247	mutex_init(&hub->status_mutex);
1248
1249	hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
1250	if (!hub->descriptor) {
1251		ret = -ENOMEM;
1252		goto fail;
1253	}
1254
 
 
 
 
 
 
 
 
 
 
 
 
1255	/* Request the entire hub descriptor.
1256	 * hub->descriptor can handle USB_MAXCHILDREN ports,
1257	 * but the hub can/will return fewer bytes here.
1258	 */
1259	ret = get_hub_descriptor(hdev, hub->descriptor);
1260	if (ret < 0) {
1261		message = "can't read hub descriptor";
1262		goto fail;
1263	} else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
1264		message = "hub has too many ports!";
1265		ret = -ENODEV;
1266		goto fail;
1267	}
1268
1269	hdev->maxchild = hub->descriptor->bNbrPorts;
1270	dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
1271		(hdev->maxchild == 1) ? "" : "s");
1272
1273	hdev->children = kzalloc(hdev->maxchild *
1274				sizeof(struct usb_device *), GFP_KERNEL);
1275	hub->port_owners = kzalloc(hdev->maxchild * sizeof(void *), GFP_KERNEL);
1276	if (!hdev->children || !hub->port_owners) {
1277		ret = -ENOMEM;
1278		goto fail;
1279	}
1280
1281	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
1282
1283	/* FIXME for USB 3.0, skip for now */
1284	if ((wHubCharacteristics & HUB_CHAR_COMPOUND) &&
1285			!(hub_is_superspeed(hdev))) {
1286		int	i;
1287		char	portstr [USB_MAXCHILDREN + 1];
1288
1289		for (i = 0; i < hdev->maxchild; i++)
1290			portstr[i] = hub->descriptor->u.hs.DeviceRemovable
1291				    [((i + 1) / 8)] & (1 << ((i + 1) % 8))
1292				? 'F' : 'R';
1293		portstr[hdev->maxchild] = 0;
1294		dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
1295	} else
1296		dev_dbg(hub_dev, "standalone hub\n");
1297
1298	switch (wHubCharacteristics & HUB_CHAR_LPSM) {
1299	case HUB_CHAR_COMMON_LPSM:
1300		dev_dbg(hub_dev, "ganged power switching\n");
1301		break;
1302	case HUB_CHAR_INDV_PORT_LPSM:
1303		dev_dbg(hub_dev, "individual port power switching\n");
1304		break;
1305	case HUB_CHAR_NO_LPSM:
1306	case HUB_CHAR_LPSM:
1307		dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
1308		break;
1309	}
1310
1311	switch (wHubCharacteristics & HUB_CHAR_OCPM) {
1312	case HUB_CHAR_COMMON_OCPM:
1313		dev_dbg(hub_dev, "global over-current protection\n");
1314		break;
1315	case HUB_CHAR_INDV_PORT_OCPM:
1316		dev_dbg(hub_dev, "individual port over-current protection\n");
1317		break;
1318	case HUB_CHAR_NO_OCPM:
1319	case HUB_CHAR_OCPM:
1320		dev_dbg(hub_dev, "no over-current protection\n");
1321		break;
1322	}
1323
1324	spin_lock_init (&hub->tt.lock);
1325	INIT_LIST_HEAD (&hub->tt.clear_list);
1326	INIT_WORK(&hub->tt.clear_work, hub_tt_work);
1327	switch (hdev->descriptor.bDeviceProtocol) {
1328	case USB_HUB_PR_FS:
1329		break;
1330	case USB_HUB_PR_HS_SINGLE_TT:
1331		dev_dbg(hub_dev, "Single TT\n");
1332		hub->tt.hub = hdev;
1333		break;
1334	case USB_HUB_PR_HS_MULTI_TT:
1335		ret = usb_set_interface(hdev, 0, 1);
1336		if (ret == 0) {
1337			dev_dbg(hub_dev, "TT per port\n");
1338			hub->tt.multi = 1;
1339		} else
1340			dev_err(hub_dev, "Using single TT (err %d)\n",
1341				ret);
1342		hub->tt.hub = hdev;
1343		break;
1344	case USB_HUB_PR_SS:
1345		/* USB 3.0 hubs don't have a TT */
1346		break;
1347	default:
1348		dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
1349			hdev->descriptor.bDeviceProtocol);
1350		break;
1351	}
1352
1353	/* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
1354	switch (wHubCharacteristics & HUB_CHAR_TTTT) {
1355		case HUB_TTTT_8_BITS:
1356			if (hdev->descriptor.bDeviceProtocol != 0) {
1357				hub->tt.think_time = 666;
1358				dev_dbg(hub_dev, "TT requires at most %d "
1359						"FS bit times (%d ns)\n",
1360					8, hub->tt.think_time);
1361			}
1362			break;
1363		case HUB_TTTT_16_BITS:
1364			hub->tt.think_time = 666 * 2;
1365			dev_dbg(hub_dev, "TT requires at most %d "
1366					"FS bit times (%d ns)\n",
1367				16, hub->tt.think_time);
1368			break;
1369		case HUB_TTTT_24_BITS:
1370			hub->tt.think_time = 666 * 3;
1371			dev_dbg(hub_dev, "TT requires at most %d "
1372					"FS bit times (%d ns)\n",
1373				24, hub->tt.think_time);
1374			break;
1375		case HUB_TTTT_32_BITS:
1376			hub->tt.think_time = 666 * 4;
1377			dev_dbg(hub_dev, "TT requires at most %d "
1378					"FS bit times (%d ns)\n",
1379				32, hub->tt.think_time);
1380			break;
1381	}
1382
1383	/* probe() zeroes hub->indicator[] */
1384	if (wHubCharacteristics & HUB_CHAR_PORTIND) {
1385		hub->has_indicators = 1;
1386		dev_dbg(hub_dev, "Port indicators are supported\n");
1387	}
1388
1389	dev_dbg(hub_dev, "power on to power good time: %dms\n",
1390		hub->descriptor->bPwrOn2PwrGood * 2);
1391
1392	/* power budgeting mostly matters with bus-powered hubs,
1393	 * and battery-powered root hubs (may provide just 8 mA).
1394	 */
1395	ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
1396	if (ret < 2) {
1397		message = "can't get hub status";
1398		goto fail;
1399	}
1400	le16_to_cpus(&hubstatus);
1401	if (hdev == hdev->bus->root_hub) {
1402		if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
1403			hub->mA_per_port = 500;
1404		else {
1405			hub->mA_per_port = hdev->bus_mA;
1406			hub->limited_power = 1;
1407		}
1408	} else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1409		dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
1410			hub->descriptor->bHubContrCurrent);
1411		hub->limited_power = 1;
1412		if (hdev->maxchild > 0) {
1413			int remaining = hdev->bus_mA -
1414					hub->descriptor->bHubContrCurrent;
1415
1416			if (remaining < hdev->maxchild * 100)
1417				dev_warn(hub_dev,
1418					"insufficient power available "
1419					"to use all downstream ports\n");
1420			hub->mA_per_port = 100;		/* 7.2.1.1 */
1421		}
1422	} else {	/* Self-powered external hub */
1423		/* FIXME: What about battery-powered external hubs that
1424		 * provide less current per port? */
1425		hub->mA_per_port = 500;
1426	}
1427	if (hub->mA_per_port < 500)
1428		dev_dbg(hub_dev, "%umA bus power budget for each child\n",
1429				hub->mA_per_port);
1430
1431	/* Update the HCD's internal representation of this hub before khubd
1432	 * starts getting port status changes for devices under the hub.
1433	 */
1434	hcd = bus_to_hcd(hdev->bus);
1435	if (hcd->driver->update_hub_device) {
1436		ret = hcd->driver->update_hub_device(hcd, hdev,
1437				&hub->tt, GFP_KERNEL);
1438		if (ret < 0) {
1439			message = "can't update HCD hub info";
1440			goto fail;
1441		}
1442	}
1443
1444	ret = hub_hub_status(hub, &hubstatus, &hubchange);
1445	if (ret < 0) {
1446		message = "can't get hub status";
1447		goto fail;
1448	}
1449
1450	/* local power status reports aren't always correct */
1451	if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
1452		dev_dbg(hub_dev, "local power source is %s\n",
1453			(hubstatus & HUB_STATUS_LOCAL_POWER)
1454			? "lost (inactive)" : "good");
1455
1456	if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
1457		dev_dbg(hub_dev, "%sover-current condition exists\n",
1458			(hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
1459
1460	/* set up the interrupt endpoint
1461	 * We use the EP's maxpacket size instead of (PORTS+1+7)/8
1462	 * bytes as USB2.0[11.12.3] says because some hubs are known
1463	 * to send more data (and thus cause overflow). For root hubs,
1464	 * maxpktsize is defined in hcd.c's fake endpoint descriptors
1465	 * to be big enough for at least USB_MAXCHILDREN ports. */
1466	pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
1467	maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
1468
1469	if (maxp > sizeof(*hub->buffer))
1470		maxp = sizeof(*hub->buffer);
1471
1472	hub->urb = usb_alloc_urb(0, GFP_KERNEL);
1473	if (!hub->urb) {
1474		ret = -ENOMEM;
1475		goto fail;
1476	}
1477
1478	usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1479		hub, endpoint->bInterval);
1480
1481	/* maybe cycle the hub leds */
1482	if (hub->has_indicators && blinkenlights)
1483		hub->indicator [0] = INDICATOR_CYCLE;
1484
1485	hub_activate(hub, HUB_INIT);
1486	return 0;
1487
1488fail:
1489	dev_err (hub_dev, "config failed, %s (err %d)\n",
1490			message, ret);
1491	/* hub_disconnect() frees urb and descriptor */
1492	return ret;
1493}
1494
1495static void hub_release(struct kref *kref)
1496{
1497	struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1498
1499	usb_put_intf(to_usb_interface(hub->intfdev));
1500	kfree(hub);
1501}
1502
1503static unsigned highspeed_hubs;
1504
1505static void hub_disconnect(struct usb_interface *intf)
1506{
1507	struct usb_hub *hub = usb_get_intfdata(intf);
1508	struct usb_device *hdev = interface_to_usbdev(intf);
1509
1510	/* Take the hub off the event list and don't let it be added again */
1511	spin_lock_irq(&hub_event_lock);
1512	if (!list_empty(&hub->event_list)) {
1513		list_del_init(&hub->event_list);
1514		usb_autopm_put_interface_no_suspend(intf);
1515	}
1516	hub->disconnected = 1;
1517	spin_unlock_irq(&hub_event_lock);
1518
1519	/* Disconnect all children and quiesce the hub */
1520	hub->error = 0;
1521	hub_quiesce(hub, HUB_DISCONNECT);
1522
1523	usb_set_intfdata (intf, NULL);
1524	hub->hdev->maxchild = 0;
1525
1526	if (hub->hdev->speed == USB_SPEED_HIGH)
1527		highspeed_hubs--;
1528
1529	usb_free_urb(hub->urb);
1530	kfree(hdev->children);
1531	kfree(hub->port_owners);
1532	kfree(hub->descriptor);
1533	kfree(hub->status);
1534	kfree(hub->buffer);
1535
1536	kref_put(&hub->kref, hub_release);
1537}
1538
1539static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1540{
1541	struct usb_host_interface *desc;
1542	struct usb_endpoint_descriptor *endpoint;
1543	struct usb_device *hdev;
1544	struct usb_hub *hub;
1545
1546	desc = intf->cur_altsetting;
1547	hdev = interface_to_usbdev(intf);
1548
1549	/* Hubs have proper suspend/resume support. */
1550	usb_enable_autosuspend(hdev);
 
 
 
 
 
 
1551
1552	if (hdev->level == MAX_TOPO_LEVEL) {
1553		dev_err(&intf->dev,
1554			"Unsupported bus topology: hub nested too deep\n");
1555		return -E2BIG;
1556	}
1557
1558#ifdef	CONFIG_USB_OTG_BLACKLIST_HUB
1559	if (hdev->parent) {
1560		dev_warn(&intf->dev, "ignoring external hub\n");
1561		return -ENODEV;
1562	}
1563#endif
1564
1565	/* Some hubs have a subclass of 1, which AFAICT according to the */
1566	/*  specs is not defined, but it works */
1567	if ((desc->desc.bInterfaceSubClass != 0) &&
1568	    (desc->desc.bInterfaceSubClass != 1)) {
1569descriptor_error:
1570		dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
1571		return -EIO;
1572	}
1573
1574	/* Multiple endpoints? What kind of mutant ninja-hub is this? */
1575	if (desc->desc.bNumEndpoints != 1)
1576		goto descriptor_error;
1577
1578	endpoint = &desc->endpoint[0].desc;
1579
1580	/* If it's not an interrupt in endpoint, we'd better punt! */
1581	if (!usb_endpoint_is_int_in(endpoint))
1582		goto descriptor_error;
1583
1584	/* We found a hub */
1585	dev_info (&intf->dev, "USB hub found\n");
1586
1587	hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1588	if (!hub) {
1589		dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
1590		return -ENOMEM;
1591	}
1592
1593	kref_init(&hub->kref);
1594	INIT_LIST_HEAD(&hub->event_list);
1595	hub->intfdev = &intf->dev;
1596	hub->hdev = hdev;
1597	INIT_DELAYED_WORK(&hub->leds, led_work);
1598	INIT_DELAYED_WORK(&hub->init_work, NULL);
1599	usb_get_intf(intf);
1600
1601	usb_set_intfdata (intf, hub);
1602	intf->needs_remote_wakeup = 1;
1603
1604	if (hdev->speed == USB_SPEED_HIGH)
1605		highspeed_hubs++;
1606
1607	if (hub_configure(hub, endpoint) >= 0)
1608		return 0;
1609
1610	hub_disconnect (intf);
1611	return -ENODEV;
1612}
1613
 
1614static int
1615hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1616{
1617	struct usb_device *hdev = interface_to_usbdev (intf);
1618
1619	/* assert ifno == 0 (part of hub spec) */
1620	switch (code) {
1621	case USBDEVFS_HUB_PORTINFO: {
1622		struct usbdevfs_hub_portinfo *info = user_data;
1623		int i;
1624
1625		spin_lock_irq(&device_state_lock);
1626		if (hdev->devnum <= 0)
1627			info->nports = 0;
1628		else {
1629			info->nports = hdev->maxchild;
1630			for (i = 0; i < info->nports; i++) {
1631				if (hdev->children[i] == NULL)
1632					info->port[i] = 0;
1633				else
1634					info->port[i] =
1635						hdev->children[i]->devnum;
1636			}
1637		}
1638		spin_unlock_irq(&device_state_lock);
1639
1640		return info->nports + 1;
1641		}
1642
1643	default:
1644		return -ENOSYS;
1645	}
1646}
1647
1648/*
1649 * Allow user programs to claim ports on a hub.  When a device is attached
1650 * to one of these "claimed" ports, the program will "own" the device.
1651 */
1652static int find_port_owner(struct usb_device *hdev, unsigned port1,
1653		void ***ppowner)
1654{
1655	if (hdev->state == USB_STATE_NOTATTACHED)
1656		return -ENODEV;
1657	if (port1 == 0 || port1 > hdev->maxchild)
1658		return -EINVAL;
1659
1660	/* This assumes that devices not managed by the hub driver
1661	 * will always have maxchild equal to 0.
1662	 */
1663	*ppowner = &(hdev_to_hub(hdev)->port_owners[port1 - 1]);
1664	return 0;
1665}
1666
1667/* In the following three functions, the caller must hold hdev's lock */
1668int usb_hub_claim_port(struct usb_device *hdev, unsigned port1, void *owner)
1669{
1670	int rc;
1671	void **powner;
1672
1673	rc = find_port_owner(hdev, port1, &powner);
1674	if (rc)
1675		return rc;
1676	if (*powner)
1677		return -EBUSY;
1678	*powner = owner;
1679	return rc;
1680}
1681
1682int usb_hub_release_port(struct usb_device *hdev, unsigned port1, void *owner)
1683{
1684	int rc;
1685	void **powner;
1686
1687	rc = find_port_owner(hdev, port1, &powner);
1688	if (rc)
1689		return rc;
1690	if (*powner != owner)
1691		return -ENOENT;
1692	*powner = NULL;
1693	return rc;
1694}
1695
1696void usb_hub_release_all_ports(struct usb_device *hdev, void *owner)
1697{
1698	int n;
1699	void **powner;
1700
1701	n = find_port_owner(hdev, 1, &powner);
1702	if (n == 0) {
1703		for (; n < hdev->maxchild; (++n, ++powner)) {
1704			if (*powner == owner)
1705				*powner = NULL;
1706		}
1707	}
1708}
1709
1710/* The caller must hold udev's lock */
1711bool usb_device_is_owned(struct usb_device *udev)
1712{
1713	struct usb_hub *hub;
1714
1715	if (udev->state == USB_STATE_NOTATTACHED || !udev->parent)
1716		return false;
1717	hub = hdev_to_hub(udev->parent);
1718	return !!hub->port_owners[udev->portnum - 1];
1719}
1720
1721
1722static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1723{
1724	int i;
1725
1726	for (i = 0; i < udev->maxchild; ++i) {
1727		if (udev->children[i])
1728			recursively_mark_NOTATTACHED(udev->children[i]);
1729	}
1730	if (udev->state == USB_STATE_SUSPENDED)
1731		udev->active_duration -= jiffies;
1732	udev->state = USB_STATE_NOTATTACHED;
1733}
1734
1735/**
1736 * usb_set_device_state - change a device's current state (usbcore, hcds)
1737 * @udev: pointer to device whose state should be changed
1738 * @new_state: new state value to be stored
1739 *
1740 * udev->state is _not_ fully protected by the device lock.  Although
1741 * most transitions are made only while holding the lock, the state can
1742 * can change to USB_STATE_NOTATTACHED at almost any time.  This
1743 * is so that devices can be marked as disconnected as soon as possible,
1744 * without having to wait for any semaphores to be released.  As a result,
1745 * all changes to any device's state must be protected by the
1746 * device_state_lock spinlock.
1747 *
1748 * Once a device has been added to the device tree, all changes to its state
1749 * should be made using this routine.  The state should _not_ be set directly.
1750 *
1751 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1752 * Otherwise udev->state is set to new_state, and if new_state is
1753 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1754 * to USB_STATE_NOTATTACHED.
1755 */
1756void usb_set_device_state(struct usb_device *udev,
1757		enum usb_device_state new_state)
1758{
1759	unsigned long flags;
1760	int wakeup = -1;
1761
1762	spin_lock_irqsave(&device_state_lock, flags);
1763	if (udev->state == USB_STATE_NOTATTACHED)
1764		;	/* do nothing */
1765	else if (new_state != USB_STATE_NOTATTACHED) {
1766
1767		/* root hub wakeup capabilities are managed out-of-band
1768		 * and may involve silicon errata ... ignore them here.
1769		 */
1770		if (udev->parent) {
1771			if (udev->state == USB_STATE_SUSPENDED
1772					|| new_state == USB_STATE_SUSPENDED)
1773				;	/* No change to wakeup settings */
1774			else if (new_state == USB_STATE_CONFIGURED)
1775				wakeup = udev->actconfig->desc.bmAttributes
1776					 & USB_CONFIG_ATT_WAKEUP;
1777			else
1778				wakeup = 0;
1779		}
1780		if (udev->state == USB_STATE_SUSPENDED &&
1781			new_state != USB_STATE_SUSPENDED)
1782			udev->active_duration -= jiffies;
1783		else if (new_state == USB_STATE_SUSPENDED &&
1784				udev->state != USB_STATE_SUSPENDED)
1785			udev->active_duration += jiffies;
1786		udev->state = new_state;
1787	} else
1788		recursively_mark_NOTATTACHED(udev);
1789	spin_unlock_irqrestore(&device_state_lock, flags);
1790	if (wakeup >= 0)
1791		device_set_wakeup_capable(&udev->dev, wakeup);
1792}
1793EXPORT_SYMBOL_GPL(usb_set_device_state);
1794
1795/*
1796 * Choose a device number.
1797 *
1798 * Device numbers are used as filenames in usbfs.  On USB-1.1 and
1799 * USB-2.0 buses they are also used as device addresses, however on
1800 * USB-3.0 buses the address is assigned by the controller hardware
1801 * and it usually is not the same as the device number.
1802 *
1803 * WUSB devices are simple: they have no hubs behind, so the mapping
1804 * device <-> virtual port number becomes 1:1. Why? to simplify the
1805 * life of the device connection logic in
1806 * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
1807 * handshake we need to assign a temporary address in the unauthorized
1808 * space. For simplicity we use the first virtual port number found to
1809 * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
1810 * and that becomes it's address [X < 128] or its unauthorized address
1811 * [X | 0x80].
1812 *
1813 * We add 1 as an offset to the one-based USB-stack port number
1814 * (zero-based wusb virtual port index) for two reasons: (a) dev addr
1815 * 0 is reserved by USB for default address; (b) Linux's USB stack
1816 * uses always #1 for the root hub of the controller. So USB stack's
1817 * port #1, which is wusb virtual-port #0 has address #2.
1818 *
1819 * Devices connected under xHCI are not as simple.  The host controller
1820 * supports virtualization, so the hardware assigns device addresses and
1821 * the HCD must setup data structures before issuing a set address
1822 * command to the hardware.
1823 */
1824static void choose_devnum(struct usb_device *udev)
1825{
1826	int		devnum;
1827	struct usb_bus	*bus = udev->bus;
1828
1829	/* If khubd ever becomes multithreaded, this will need a lock */
1830	if (udev->wusb) {
1831		devnum = udev->portnum + 1;
1832		BUG_ON(test_bit(devnum, bus->devmap.devicemap));
1833	} else {
1834		/* Try to allocate the next devnum beginning at
1835		 * bus->devnum_next. */
1836		devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1837					    bus->devnum_next);
1838		if (devnum >= 128)
1839			devnum = find_next_zero_bit(bus->devmap.devicemap,
1840						    128, 1);
1841		bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1842	}
1843	if (devnum < 128) {
1844		set_bit(devnum, bus->devmap.devicemap);
1845		udev->devnum = devnum;
1846	}
1847}
1848
1849static void release_devnum(struct usb_device *udev)
1850{
1851	if (udev->devnum > 0) {
1852		clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1853		udev->devnum = -1;
1854	}
1855}
1856
1857static void update_devnum(struct usb_device *udev, int devnum)
1858{
1859	/* The address for a WUSB device is managed by wusbcore. */
1860	if (!udev->wusb)
1861		udev->devnum = devnum;
1862}
1863
1864static void hub_free_dev(struct usb_device *udev)
1865{
1866	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1867
1868	/* Root hubs aren't real devices, so don't free HCD resources */
1869	if (hcd->driver->free_dev && udev->parent)
1870		hcd->driver->free_dev(hcd, udev);
1871}
1872
1873/**
1874 * usb_disconnect - disconnect a device (usbcore-internal)
1875 * @pdev: pointer to device being disconnected
1876 * Context: !in_interrupt ()
1877 *
1878 * Something got disconnected. Get rid of it and all of its children.
1879 *
1880 * If *pdev is a normal device then the parent hub must already be locked.
1881 * If *pdev is a root hub then this routine will acquire the
1882 * usb_bus_list_lock on behalf of the caller.
1883 *
1884 * Only hub drivers (including virtual root hub drivers for host
1885 * controllers) should ever call this.
1886 *
1887 * This call is synchronous, and may not be used in an interrupt context.
1888 */
1889void usb_disconnect(struct usb_device **pdev)
1890{
1891	struct usb_device	*udev = *pdev;
1892	int			i;
 
 
 
 
 
 
1893
1894	/* mark the device as inactive, so any further urb submissions for
1895	 * this device (and any of its children) will fail immediately.
1896	 * this quiesces everything except pending urbs.
1897	 */
1898	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1899	dev_info(&udev->dev, "USB disconnect, device number %d\n",
1900			udev->devnum);
1901
1902	usb_lock_device(udev);
1903
1904	/* Free up all the children before we remove this device */
1905	for (i = 0; i < udev->maxchild; i++) {
1906		if (udev->children[i])
1907			usb_disconnect(&udev->children[i]);
1908	}
1909
1910	/* deallocate hcd/hardware state ... nuking all pending urbs and
1911	 * cleaning up all state associated with the current configuration
1912	 * so that the hardware is now fully quiesced.
1913	 */
1914	dev_dbg (&udev->dev, "unregistering device\n");
 
1915	usb_disable_device(udev, 0);
 
1916	usb_hcd_synchronize_unlinks(udev);
1917
1918	usb_remove_ep_devs(&udev->ep0);
1919	usb_unlock_device(udev);
1920
1921	/* Unregister the device.  The device driver is responsible
1922	 * for de-configuring the device and invoking the remove-device
1923	 * notifier chain (used by usbfs and possibly others).
1924	 */
1925	device_del(&udev->dev);
1926
1927	/* Free the device number and delete the parent's children[]
1928	 * (or root_hub) pointer.
1929	 */
1930	release_devnum(udev);
1931
1932	/* Avoid races with recursively_mark_NOTATTACHED() */
1933	spin_lock_irq(&device_state_lock);
1934	*pdev = NULL;
1935	spin_unlock_irq(&device_state_lock);
1936
1937	hub_free_dev(udev);
1938
1939	put_device(&udev->dev);
1940}
1941
1942#ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
1943static void show_string(struct usb_device *udev, char *id, char *string)
1944{
1945	if (!string)
1946		return;
1947	dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1948}
1949
1950static void announce_device(struct usb_device *udev)
1951{
1952	dev_info(&udev->dev, "New USB device found, idVendor=%04x, idProduct=%04x\n",
1953		le16_to_cpu(udev->descriptor.idVendor),
1954		le16_to_cpu(udev->descriptor.idProduct));
1955	dev_info(&udev->dev,
1956		"New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
1957		udev->descriptor.iManufacturer,
1958		udev->descriptor.iProduct,
1959		udev->descriptor.iSerialNumber);
1960	show_string(udev, "Product", udev->product);
1961	show_string(udev, "Manufacturer", udev->manufacturer);
1962	show_string(udev, "SerialNumber", udev->serial);
1963}
1964#else
1965static inline void announce_device(struct usb_device *udev) { }
1966#endif
1967
1968#ifdef	CONFIG_USB_OTG
1969#include "otg_whitelist.h"
1970#endif
1971
1972/**
1973 * usb_enumerate_device_otg - FIXME (usbcore-internal)
1974 * @udev: newly addressed device (in ADDRESS state)
1975 *
1976 * Finish enumeration for On-The-Go devices
1977 */
1978static int usb_enumerate_device_otg(struct usb_device *udev)
1979{
1980	int err = 0;
1981
1982#ifdef	CONFIG_USB_OTG
1983	/*
1984	 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1985	 * to wake us after we've powered off VBUS; and HNP, switching roles
1986	 * "host" to "peripheral".  The OTG descriptor helps figure this out.
1987	 */
1988	if (!udev->bus->is_b_host
1989			&& udev->config
1990			&& udev->parent == udev->bus->root_hub) {
1991		struct usb_otg_descriptor	*desc = NULL;
1992		struct usb_bus			*bus = udev->bus;
1993
1994		/* descriptor may appear anywhere in config */
1995		if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1996					le16_to_cpu(udev->config[0].desc.wTotalLength),
1997					USB_DT_OTG, (void **) &desc) == 0) {
1998			if (desc->bmAttributes & USB_OTG_HNP) {
1999				unsigned		port1 = udev->portnum;
2000
2001				dev_info(&udev->dev,
2002					"Dual-Role OTG device on %sHNP port\n",
2003					(port1 == bus->otg_port)
2004						? "" : "non-");
2005
2006				/* enable HNP before suspend, it's simpler */
2007				if (port1 == bus->otg_port)
2008					bus->b_hnp_enable = 1;
2009				err = usb_control_msg(udev,
2010					usb_sndctrlpipe(udev, 0),
2011					USB_REQ_SET_FEATURE, 0,
2012					bus->b_hnp_enable
2013						? USB_DEVICE_B_HNP_ENABLE
2014						: USB_DEVICE_A_ALT_HNP_SUPPORT,
2015					0, NULL, 0, USB_CTRL_SET_TIMEOUT);
2016				if (err < 0) {
2017					/* OTG MESSAGE: report errors here,
2018					 * customize to match your product.
2019					 */
2020					dev_info(&udev->dev,
2021						"can't set HNP mode: %d\n",
2022						err);
2023					bus->b_hnp_enable = 0;
2024				}
2025			}
2026		}
2027	}
2028
2029	if (!is_targeted(udev)) {
2030
2031		/* Maybe it can talk to us, though we can't talk to it.
2032		 * (Includes HNP test device.)
2033		 */
2034		if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
2035			err = usb_port_suspend(udev, PMSG_SUSPEND);
2036			if (err < 0)
2037				dev_dbg(&udev->dev, "HNP fail, %d\n", err);
2038		}
2039		err = -ENOTSUPP;
2040		goto fail;
2041	}
2042fail:
2043#endif
2044	return err;
2045}
2046
2047
2048/**
2049 * usb_enumerate_device - Read device configs/intfs/otg (usbcore-internal)
2050 * @udev: newly addressed device (in ADDRESS state)
2051 *
2052 * This is only called by usb_new_device() and usb_authorize_device()
2053 * and FIXME -- all comments that apply to them apply here wrt to
2054 * environment.
2055 *
2056 * If the device is WUSB and not authorized, we don't attempt to read
2057 * the string descriptors, as they will be errored out by the device
2058 * until it has been authorized.
2059 */
2060static int usb_enumerate_device(struct usb_device *udev)
2061{
2062	int err;
2063
2064	if (udev->config == NULL) {
2065		err = usb_get_configuration(udev);
2066		if (err < 0) {
2067			dev_err(&udev->dev, "can't read configurations, error %d\n",
2068				err);
2069			goto fail;
2070		}
2071	}
2072	if (udev->wusb == 1 && udev->authorized == 0) {
2073		udev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
2074		udev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
2075		udev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
2076	}
2077	else {
2078		/* read the standard strings and cache them if present */
2079		udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
2080		udev->manufacturer = usb_cache_string(udev,
2081						      udev->descriptor.iManufacturer);
2082		udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
2083	}
2084	err = usb_enumerate_device_otg(udev);
2085fail:
2086	return err;
2087}
2088
2089static void set_usb_port_removable(struct usb_device *udev)
2090{
2091	struct usb_device *hdev = udev->parent;
2092	struct usb_hub *hub;
2093	u8 port = udev->portnum;
2094	u16 wHubCharacteristics;
2095	bool removable = true;
2096
2097	if (!hdev)
2098		return;
2099
2100	hub = hdev_to_hub(udev->parent);
2101
2102	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2103
2104	if (!(wHubCharacteristics & HUB_CHAR_COMPOUND))
2105		return;
2106
2107	if (hub_is_superspeed(hdev)) {
2108		if (hub->descriptor->u.ss.DeviceRemovable & (1 << port))
2109			removable = false;
2110	} else {
2111		if (hub->descriptor->u.hs.DeviceRemovable[port / 8] & (1 << (port % 8)))
2112			removable = false;
2113	}
2114
2115	if (removable)
2116		udev->removable = USB_DEVICE_REMOVABLE;
2117	else
2118		udev->removable = USB_DEVICE_FIXED;
2119}
2120
2121/**
2122 * usb_new_device - perform initial device setup (usbcore-internal)
2123 * @udev: newly addressed device (in ADDRESS state)
2124 *
2125 * This is called with devices which have been detected but not fully
2126 * enumerated.  The device descriptor is available, but not descriptors
2127 * for any device configuration.  The caller must have locked either
2128 * the parent hub (if udev is a normal device) or else the
2129 * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
2130 * udev has already been installed, but udev is not yet visible through
2131 * sysfs or other filesystem code.
2132 *
2133 * It will return if the device is configured properly or not.  Zero if
2134 * the interface was registered with the driver core; else a negative
2135 * errno value.
2136 *
2137 * This call is synchronous, and may not be used in an interrupt context.
2138 *
2139 * Only the hub driver or root-hub registrar should ever call this.
2140 */
2141int usb_new_device(struct usb_device *udev)
2142{
2143	int err;
2144
2145	if (udev->parent) {
2146		/* Initialize non-root-hub device wakeup to disabled;
2147		 * device (un)configuration controls wakeup capable
2148		 * sysfs power/wakeup controls wakeup enabled/disabled
2149		 */
2150		device_init_wakeup(&udev->dev, 0);
2151	}
2152
2153	/* Tell the runtime-PM framework the device is active */
2154	pm_runtime_set_active(&udev->dev);
2155	pm_runtime_get_noresume(&udev->dev);
2156	pm_runtime_use_autosuspend(&udev->dev);
2157	pm_runtime_enable(&udev->dev);
2158
2159	/* By default, forbid autosuspend for all devices.  It will be
2160	 * allowed for hubs during binding.
2161	 */
2162	usb_disable_autosuspend(udev);
2163
2164	err = usb_enumerate_device(udev);	/* Read descriptors */
2165	if (err < 0)
2166		goto fail;
2167	dev_dbg(&udev->dev, "udev %d, busnum %d, minor = %d\n",
2168			udev->devnum, udev->bus->busnum,
2169			(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2170	/* export the usbdev device-node for libusb */
2171	udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
2172			(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2173
2174	/* Tell the world! */
2175	announce_device(udev);
2176
2177	if (udev->serial)
2178		add_device_randomness(udev->serial, strlen(udev->serial));
2179	if (udev->product)
2180		add_device_randomness(udev->product, strlen(udev->product));
2181	if (udev->manufacturer)
2182		add_device_randomness(udev->manufacturer,
2183				      strlen(udev->manufacturer));
2184
2185	device_enable_async_suspend(&udev->dev);
2186
2187	/*
2188	 * check whether the hub marks this port as non-removable. Do it
2189	 * now so that platform-specific data can override it in
2190	 * device_add()
2191	 */
2192	if (udev->parent)
2193		set_usb_port_removable(udev);
2194
2195	/* Register the device.  The device driver is responsible
2196	 * for configuring the device and invoking the add-device
2197	 * notifier chain (used by usbfs and possibly others).
2198	 */
2199	err = device_add(&udev->dev);
2200	if (err) {
2201		dev_err(&udev->dev, "can't device_add, error %d\n", err);
2202		goto fail;
2203	}
2204
2205	(void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev);
2206	usb_mark_last_busy(udev);
2207	pm_runtime_put_sync_autosuspend(&udev->dev);
2208	return err;
2209
2210fail:
2211	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2212	pm_runtime_disable(&udev->dev);
2213	pm_runtime_set_suspended(&udev->dev);
2214	return err;
2215}
2216
2217
2218/**
2219 * usb_deauthorize_device - deauthorize a device (usbcore-internal)
2220 * @usb_dev: USB device
2221 *
2222 * Move the USB device to a very basic state where interfaces are disabled
2223 * and the device is in fact unconfigured and unusable.
2224 *
2225 * We share a lock (that we have) with device_del(), so we need to
2226 * defer its call.
2227 */
2228int usb_deauthorize_device(struct usb_device *usb_dev)
2229{
2230	usb_lock_device(usb_dev);
2231	if (usb_dev->authorized == 0)
2232		goto out_unauthorized;
2233
2234	usb_dev->authorized = 0;
2235	usb_set_configuration(usb_dev, -1);
2236
2237	kfree(usb_dev->product);
2238	usb_dev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
2239	kfree(usb_dev->manufacturer);
2240	usb_dev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
2241	kfree(usb_dev->serial);
2242	usb_dev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
2243
2244	usb_destroy_configuration(usb_dev);
2245	usb_dev->descriptor.bNumConfigurations = 0;
2246
2247out_unauthorized:
2248	usb_unlock_device(usb_dev);
2249	return 0;
2250}
2251
2252
2253int usb_authorize_device(struct usb_device *usb_dev)
2254{
2255	int result = 0, c;
2256
2257	usb_lock_device(usb_dev);
2258	if (usb_dev->authorized == 1)
2259		goto out_authorized;
2260
2261	result = usb_autoresume_device(usb_dev);
2262	if (result < 0) {
2263		dev_err(&usb_dev->dev,
2264			"can't autoresume for authorization: %d\n", result);
2265		goto error_autoresume;
2266	}
2267	result = usb_get_device_descriptor(usb_dev, sizeof(usb_dev->descriptor));
2268	if (result < 0) {
2269		dev_err(&usb_dev->dev, "can't re-read device descriptor for "
2270			"authorization: %d\n", result);
2271		goto error_device_descriptor;
2272	}
2273
2274	kfree(usb_dev->product);
2275	usb_dev->product = NULL;
2276	kfree(usb_dev->manufacturer);
2277	usb_dev->manufacturer = NULL;
2278	kfree(usb_dev->serial);
2279	usb_dev->serial = NULL;
2280
2281	usb_dev->authorized = 1;
2282	result = usb_enumerate_device(usb_dev);
2283	if (result < 0)
2284		goto error_enumerate;
2285	/* Choose and set the configuration.  This registers the interfaces
2286	 * with the driver core and lets interface drivers bind to them.
2287	 */
2288	c = usb_choose_configuration(usb_dev);
2289	if (c >= 0) {
2290		result = usb_set_configuration(usb_dev, c);
2291		if (result) {
2292			dev_err(&usb_dev->dev,
2293				"can't set config #%d, error %d\n", c, result);
2294			/* This need not be fatal.  The user can try to
2295			 * set other configurations. */
2296		}
2297	}
2298	dev_info(&usb_dev->dev, "authorized to connect\n");
2299
2300error_enumerate:
2301error_device_descriptor:
2302	usb_autosuspend_device(usb_dev);
2303error_autoresume:
2304out_authorized:
2305	usb_unlock_device(usb_dev);	// complements locktree
2306	return result;
2307}
2308
2309
2310/* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
2311static unsigned hub_is_wusb(struct usb_hub *hub)
2312{
2313	struct usb_hcd *hcd;
2314	if (hub->hdev->parent != NULL)  /* not a root hub? */
2315		return 0;
2316	hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
2317	return hcd->wireless;
2318}
2319
2320
2321#define PORT_RESET_TRIES	5
2322#define SET_ADDRESS_TRIES	2
2323#define GET_DESCRIPTOR_TRIES	2
2324#define SET_CONFIG_TRIES	(2 * (use_both_schemes + 1))
2325#define USE_NEW_SCHEME(i)	((i) / 2 == (int)old_scheme_first)
2326
2327#define HUB_ROOT_RESET_TIME	50	/* times are in msec */
2328#define HUB_SHORT_RESET_TIME	10
2329#define HUB_BH_RESET_TIME	50
2330#define HUB_LONG_RESET_TIME	200
2331#define HUB_RESET_TIMEOUT	500
2332
2333static int hub_port_reset(struct usb_hub *hub, int port1,
2334			struct usb_device *udev, unsigned int delay, bool warm);
2335
2336/* Is a USB 3.0 port in the Inactive or Complinance Mode state?
2337 * Port worm reset is required to recover
2338 */
2339static bool hub_port_warm_reset_required(struct usb_hub *hub, u16 portstatus)
2340{
2341	return hub_is_superspeed(hub->hdev) &&
2342		(((portstatus & USB_PORT_STAT_LINK_STATE) ==
2343		  USB_SS_PORT_LS_SS_INACTIVE) ||
2344		 ((portstatus & USB_PORT_STAT_LINK_STATE) ==
2345		  USB_SS_PORT_LS_COMP_MOD)) ;
2346}
2347
2348static int hub_port_wait_reset(struct usb_hub *hub, int port1,
2349			struct usb_device *udev, unsigned int delay, bool warm)
2350{
2351	int delay_time, ret;
2352	u16 portstatus;
2353	u16 portchange;
2354
2355	for (delay_time = 0;
2356			delay_time < HUB_RESET_TIMEOUT;
2357			delay_time += delay) {
2358		/* wait to give the device a chance to reset */
2359		msleep(delay);
2360
2361		/* read and decode port status */
2362		ret = hub_port_status(hub, port1, &portstatus, &portchange);
2363		if (ret < 0)
2364			return ret;
2365
2366		/*
2367		 * Some buggy devices require a warm reset to be issued even
2368		 * when the port appears not to be connected.
2369		 */
2370		if (!warm) {
2371			/*
2372			 * Some buggy devices can cause an NEC host controller
2373			 * to transition to the "Error" state after a hot port
2374			 * reset.  This will show up as the port state in
2375			 * "Inactive", and the port may also report a
2376			 * disconnect.  Forcing a warm port reset seems to make
2377			 * the device work.
2378			 *
2379			 * See https://bugzilla.kernel.org/show_bug.cgi?id=41752
2380			 */
2381			if (hub_port_warm_reset_required(hub, portstatus)) {
2382				int ret;
2383
2384				if ((portchange & USB_PORT_STAT_C_CONNECTION))
2385					clear_port_feature(hub->hdev, port1,
2386							USB_PORT_FEAT_C_CONNECTION);
2387				if (portchange & USB_PORT_STAT_C_LINK_STATE)
2388					clear_port_feature(hub->hdev, port1,
2389							USB_PORT_FEAT_C_PORT_LINK_STATE);
2390				if (portchange & USB_PORT_STAT_C_RESET)
2391					clear_port_feature(hub->hdev, port1,
2392							USB_PORT_FEAT_C_RESET);
2393				dev_dbg(hub->intfdev, "hot reset failed, warm reset port %d\n",
2394						port1);
2395				ret = hub_port_reset(hub, port1,
2396						udev, HUB_BH_RESET_TIME,
2397						true);
2398				if ((portchange & USB_PORT_STAT_C_CONNECTION))
2399					clear_port_feature(hub->hdev, port1,
2400							USB_PORT_FEAT_C_CONNECTION);
2401				return ret;
2402			}
2403			/* Device went away? */
2404			if (!(portstatus & USB_PORT_STAT_CONNECTION))
2405				return -ENOTCONN;
2406
2407			/* bomb out completely if the connection bounced */
2408			if ((portchange & USB_PORT_STAT_C_CONNECTION))
2409				return -ENOTCONN;
2410
2411			/* if we`ve finished resetting, then break out of
2412			 * the loop
2413			 */
2414			if (!(portstatus & USB_PORT_STAT_RESET) &&
2415			    (portstatus & USB_PORT_STAT_ENABLE)) {
2416				if (hub_is_wusb(hub))
2417					udev->speed = USB_SPEED_WIRELESS;
2418				else if (hub_is_superspeed(hub->hdev))
2419					udev->speed = USB_SPEED_SUPER;
2420				else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
2421					udev->speed = USB_SPEED_HIGH;
2422				else if (portstatus & USB_PORT_STAT_LOW_SPEED)
2423					udev->speed = USB_SPEED_LOW;
2424				else
2425					udev->speed = USB_SPEED_FULL;
2426				return 0;
2427			}
2428		} else {
2429			if (portchange & USB_PORT_STAT_C_BH_RESET)
2430				return 0;
2431		}
2432
2433		/* switch to the long delay after two short delay failures */
2434		if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
2435			delay = HUB_LONG_RESET_TIME;
2436
2437		dev_dbg (hub->intfdev,
2438			"port %d not %sreset yet, waiting %dms\n",
2439			port1, warm ? "warm " : "", delay);
2440	}
2441
2442	return -EBUSY;
2443}
2444
2445static void hub_port_finish_reset(struct usb_hub *hub, int port1,
2446			struct usb_device *udev, int *status, bool warm)
2447{
2448	switch (*status) {
2449	case 0:
2450		if (!warm) {
2451			struct usb_hcd *hcd;
2452			/* TRSTRCY = 10 ms; plus some extra */
2453			msleep(10 + 40);
2454			update_devnum(udev, 0);
2455			hcd = bus_to_hcd(udev->bus);
2456			if (hcd->driver->reset_device) {
2457				*status = hcd->driver->reset_device(hcd, udev);
2458				if (*status < 0) {
2459					dev_err(&udev->dev, "Cannot reset "
2460							"HCD device state\n");
2461					break;
2462				}
2463			}
2464		}
2465		/* FALL THROUGH */
2466	case -ENOTCONN:
2467	case -ENODEV:
2468		clear_port_feature(hub->hdev,
2469				port1, USB_PORT_FEAT_C_RESET);
2470		/* FIXME need disconnect() for NOTATTACHED device */
2471		if (warm) {
2472			clear_port_feature(hub->hdev, port1,
2473					USB_PORT_FEAT_C_BH_PORT_RESET);
2474			clear_port_feature(hub->hdev, port1,
2475					USB_PORT_FEAT_C_PORT_LINK_STATE);
2476		} else {
2477			usb_set_device_state(udev, *status
2478					? USB_STATE_NOTATTACHED
2479					: USB_STATE_DEFAULT);
2480		}
2481		break;
2482	}
2483}
2484
2485/* Handle port reset and port warm(BH) reset (for USB3 protocol ports) */
2486static int hub_port_reset(struct usb_hub *hub, int port1,
2487			struct usb_device *udev, unsigned int delay, bool warm)
2488{
2489	int i, status;
 
2490
2491	if (!warm) {
2492		/* Block EHCI CF initialization during the port reset.
2493		 * Some companion controllers don't like it when they mix.
2494		 */
2495		down_read(&ehci_cf_port_reset_rwsem);
2496	} else {
2497		if (!hub_is_superspeed(hub->hdev)) {
2498			dev_err(hub->intfdev, "only USB3 hub support "
2499						"warm reset\n");
2500			return -EINVAL;
2501		}
2502	}
2503
2504	/* Reset the port */
2505	for (i = 0; i < PORT_RESET_TRIES; i++) {
2506		status = set_port_feature(hub->hdev, port1, (warm ?
2507					USB_PORT_FEAT_BH_PORT_RESET :
2508					USB_PORT_FEAT_RESET));
2509		if (status) {
2510			dev_err(hub->intfdev,
2511					"cannot %sreset port %d (err = %d)\n",
2512					warm ? "warm " : "", port1, status);
2513		} else {
2514			status = hub_port_wait_reset(hub, port1, udev, delay,
2515								warm);
2516			if (status && status != -ENOTCONN)
2517				dev_dbg(hub->intfdev,
2518						"port_wait_reset: err = %d\n",
2519						status);
2520		}
2521
2522		/* return on disconnect or reset */
2523		if (status == 0 || status == -ENOTCONN || status == -ENODEV) {
2524			hub_port_finish_reset(hub, port1, udev, &status, warm);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2525			goto done;
2526		}
2527
2528		dev_dbg (hub->intfdev,
2529			"port %d not enabled, trying %sreset again...\n",
2530			port1, warm ? "warm " : "");
2531		delay = HUB_LONG_RESET_TIME;
2532	}
2533
2534	dev_err (hub->intfdev,
2535		"Cannot enable port %i.  Maybe the USB cable is bad?\n",
2536		port1);
2537
2538done:
2539	if (!warm)
2540		up_read(&ehci_cf_port_reset_rwsem);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2541
2542	return status;
2543}
2544
2545/* Check if a port is power on */
2546static int port_is_power_on(struct usb_hub *hub, unsigned portstatus)
2547{
2548	int ret = 0;
2549
2550	if (hub_is_superspeed(hub->hdev)) {
2551		if (portstatus & USB_SS_PORT_STAT_POWER)
2552			ret = 1;
2553	} else {
2554		if (portstatus & USB_PORT_STAT_POWER)
2555			ret = 1;
2556	}
2557
2558	return ret;
2559}
2560
2561#ifdef	CONFIG_PM
2562
2563/* Check if a port is suspended(USB2.0 port) or in U3 state(USB3.0 port) */
2564static int port_is_suspended(struct usb_hub *hub, unsigned portstatus)
2565{
2566	int ret = 0;
2567
2568	if (hub_is_superspeed(hub->hdev)) {
2569		if ((portstatus & USB_PORT_STAT_LINK_STATE)
2570				== USB_SS_PORT_LS_U3)
2571			ret = 1;
2572	} else {
2573		if (portstatus & USB_PORT_STAT_SUSPEND)
2574			ret = 1;
2575	}
2576
2577	return ret;
2578}
2579
2580/* Determine whether the device on a port is ready for a normal resume,
2581 * is ready for a reset-resume, or should be disconnected.
2582 */
2583static int check_port_resume_type(struct usb_device *udev,
2584		struct usb_hub *hub, int port1,
2585		int status, unsigned portchange, unsigned portstatus)
2586{
2587	/* Is the device still present? */
2588	if (status || port_is_suspended(hub, portstatus) ||
2589			!port_is_power_on(hub, portstatus) ||
2590			!(portstatus & USB_PORT_STAT_CONNECTION)) {
2591		if (status >= 0)
2592			status = -ENODEV;
2593	}
2594
2595	/* Can't do a normal resume if the port isn't enabled,
2596	 * so try a reset-resume instead.
2597	 */
2598	else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
2599		if (udev->persist_enabled)
2600			udev->reset_resume = 1;
2601		else
2602			status = -ENODEV;
2603	}
2604
2605	if (status) {
2606		dev_dbg(hub->intfdev,
2607				"port %d status %04x.%04x after resume, %d\n",
2608				port1, portchange, portstatus, status);
2609	} else if (udev->reset_resume) {
2610
2611		/* Late port handoff can set status-change bits */
2612		if (portchange & USB_PORT_STAT_C_CONNECTION)
2613			clear_port_feature(hub->hdev, port1,
2614					USB_PORT_FEAT_C_CONNECTION);
2615		if (portchange & USB_PORT_STAT_C_ENABLE)
2616			clear_port_feature(hub->hdev, port1,
2617					USB_PORT_FEAT_C_ENABLE);
2618	}
2619
2620	return status;
2621}
2622
2623#ifdef	CONFIG_USB_SUSPEND
2624
2625/*
2626 * usb_port_suspend - suspend a usb device's upstream port
2627 * @udev: device that's no longer in active use, not a root hub
2628 * Context: must be able to sleep; device not locked; pm locks held
2629 *
2630 * Suspends a USB device that isn't in active use, conserving power.
2631 * Devices may wake out of a suspend, if anything important happens,
2632 * using the remote wakeup mechanism.  They may also be taken out of
2633 * suspend by the host, using usb_port_resume().  It's also routine
2634 * to disconnect devices while they are suspended.
2635 *
2636 * This only affects the USB hardware for a device; its interfaces
2637 * (and, for hubs, child devices) must already have been suspended.
2638 *
2639 * Selective port suspend reduces power; most suspended devices draw
2640 * less than 500 uA.  It's also used in OTG, along with remote wakeup.
2641 * All devices below the suspended port are also suspended.
2642 *
2643 * Devices leave suspend state when the host wakes them up.  Some devices
2644 * also support "remote wakeup", where the device can activate the USB
2645 * tree above them to deliver data, such as a keypress or packet.  In
2646 * some cases, this wakes the USB host.
2647 *
2648 * Suspending OTG devices may trigger HNP, if that's been enabled
2649 * between a pair of dual-role devices.  That will change roles, such
2650 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
2651 *
2652 * Devices on USB hub ports have only one "suspend" state, corresponding
2653 * to ACPI D2, "may cause the device to lose some context".
2654 * State transitions include:
2655 *
2656 *   - suspend, resume ... when the VBUS power link stays live
2657 *   - suspend, disconnect ... VBUS lost
2658 *
2659 * Once VBUS drop breaks the circuit, the port it's using has to go through
2660 * normal re-enumeration procedures, starting with enabling VBUS power.
2661 * Other than re-initializing the hub (plug/unplug, except for root hubs),
2662 * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
2663 * timer, no SRP, no requests through sysfs.
2664 *
2665 * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
2666 * the root hub for their bus goes into global suspend ... so we don't
2667 * (falsely) update the device power state to say it suspended.
2668 *
2669 * Returns 0 on success, else negative errno.
2670 */
2671int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
2672{
2673	struct usb_hub	*hub = hdev_to_hub(udev->parent);
2674	int		port1 = udev->portnum;
2675	int		status;
2676
 
 
2677	/* enable remote wakeup when appropriate; this lets the device
2678	 * wake up the upstream hub (including maybe the root hub).
2679	 *
2680	 * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
2681	 * we don't explicitly enable it here.
2682	 */
2683	if (udev->do_remote_wakeup) {
2684		if (!hub_is_superspeed(hub->hdev)) {
2685			status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2686					USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
2687					USB_DEVICE_REMOTE_WAKEUP, 0,
2688					NULL, 0,
2689					USB_CTRL_SET_TIMEOUT);
2690		} else {
2691			/* Assume there's only one function on the USB 3.0
2692			 * device and enable remote wake for the first
2693			 * interface. FIXME if the interface association
2694			 * descriptor shows there's more than one function.
2695			 */
2696			status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2697					USB_REQ_SET_FEATURE,
2698					USB_RECIP_INTERFACE,
2699					USB_INTRF_FUNC_SUSPEND,
2700					USB_INTRF_FUNC_SUSPEND_RW |
2701					USB_INTRF_FUNC_SUSPEND_LP,
2702					NULL, 0,
2703					USB_CTRL_SET_TIMEOUT);
2704		}
2705		if (status) {
2706			dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
2707					status);
2708			/* bail if autosuspend is requested */
2709			if (PMSG_IS_AUTO(msg))
2710				return status;
2711		}
2712	}
2713
2714	/* disable USB2 hardware LPM */
2715	if (udev->usb2_hw_lpm_enabled == 1)
2716		usb_set_usb2_hardware_lpm(udev, 0);
2717
2718	if (usb_unlocked_disable_lpm(udev)) {
2719		dev_err(&udev->dev, "%s Failed to disable LPM before suspend\n.",
2720				__func__);
2721		return -ENOMEM;
2722	}
2723
2724	/* see 7.1.7.6 */
2725	if (hub_is_superspeed(hub->hdev))
2726		status = set_port_feature(hub->hdev,
2727				port1 | (USB_SS_PORT_LS_U3 << 3),
2728				USB_PORT_FEAT_LINK_STATE);
2729	else
2730		status = set_port_feature(hub->hdev, port1,
2731						USB_PORT_FEAT_SUSPEND);
2732	if (status) {
2733		dev_dbg(hub->intfdev, "can't suspend port %d, status %d\n",
2734				port1, status);
2735		/* paranoia:  "should not happen" */
2736		if (udev->do_remote_wakeup)
2737			(void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2738				USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
2739				USB_DEVICE_REMOTE_WAKEUP, 0,
2740				NULL, 0,
2741				USB_CTRL_SET_TIMEOUT);
2742
2743		/* Try to enable USB2 hardware LPM again */
2744		if (udev->usb2_hw_lpm_capable == 1)
2745			usb_set_usb2_hardware_lpm(udev, 1);
2746
2747		/* Try to enable USB3 LPM again */
2748		usb_unlocked_enable_lpm(udev);
2749
2750		/* System sleep transitions should never fail */
2751		if (!PMSG_IS_AUTO(msg))
2752			status = 0;
2753	} else {
2754		/* device has up to 10 msec to fully suspend */
2755		dev_dbg(&udev->dev, "usb %ssuspend, wakeup %d\n",
2756				(PMSG_IS_AUTO(msg) ? "auto-" : ""),
2757				udev->do_remote_wakeup);
2758		usb_set_device_state(udev, USB_STATE_SUSPENDED);
2759		msleep(10);
2760	}
2761	usb_mark_last_busy(hub->hdev);
2762	return status;
2763}
2764
2765/*
2766 * If the USB "suspend" state is in use (rather than "global suspend"),
2767 * many devices will be individually taken out of suspend state using
2768 * special "resume" signaling.  This routine kicks in shortly after
2769 * hardware resume signaling is finished, either because of selective
2770 * resume (by host) or remote wakeup (by device) ... now see what changed
2771 * in the tree that's rooted at this device.
2772 *
2773 * If @udev->reset_resume is set then the device is reset before the
2774 * status check is done.
2775 */
2776static int finish_port_resume(struct usb_device *udev)
2777{
2778	int	status = 0;
2779	u16	devstatus;
2780
2781	/* caller owns the udev device lock */
2782	dev_dbg(&udev->dev, "%s\n",
2783		udev->reset_resume ? "finish reset-resume" : "finish resume");
2784
2785	/* usb ch9 identifies four variants of SUSPENDED, based on what
2786	 * state the device resumes to.  Linux currently won't see the
2787	 * first two on the host side; they'd be inside hub_port_init()
2788	 * during many timeouts, but khubd can't suspend until later.
2789	 */
2790	usb_set_device_state(udev, udev->actconfig
2791			? USB_STATE_CONFIGURED
2792			: USB_STATE_ADDRESS);
2793
2794	/* 10.5.4.5 says not to reset a suspended port if the attached
2795	 * device is enabled for remote wakeup.  Hence the reset
2796	 * operation is carried out here, after the port has been
2797	 * resumed.
2798	 */
2799	if (udev->reset_resume)
2800 retry_reset_resume:
2801		status = usb_reset_and_verify_device(udev);
2802
2803 	/* 10.5.4.5 says be sure devices in the tree are still there.
2804 	 * For now let's assume the device didn't go crazy on resume,
2805	 * and device drivers will know about any resume quirks.
2806	 */
2807	if (status == 0) {
2808		devstatus = 0;
2809		status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
2810		if (status >= 0)
2811			status = (status > 0 ? 0 : -ENODEV);
2812
2813		/* If a normal resume failed, try doing a reset-resume */
2814		if (status && !udev->reset_resume && udev->persist_enabled) {
2815			dev_dbg(&udev->dev, "retry with reset-resume\n");
2816			udev->reset_resume = 1;
2817			goto retry_reset_resume;
2818		}
2819	}
2820
2821	if (status) {
2822		dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
2823				status);
2824	} else if (udev->actconfig) {
2825		le16_to_cpus(&devstatus);
2826		if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
2827			status = usb_control_msg(udev,
2828					usb_sndctrlpipe(udev, 0),
2829					USB_REQ_CLEAR_FEATURE,
2830						USB_RECIP_DEVICE,
2831					USB_DEVICE_REMOTE_WAKEUP, 0,
2832					NULL, 0,
2833					USB_CTRL_SET_TIMEOUT);
2834			if (status)
2835				dev_dbg(&udev->dev,
2836					"disable remote wakeup, status %d\n",
2837					status);
2838		}
2839		status = 0;
2840	}
2841	return status;
2842}
2843
2844/*
2845 * usb_port_resume - re-activate a suspended usb device's upstream port
2846 * @udev: device to re-activate, not a root hub
2847 * Context: must be able to sleep; device not locked; pm locks held
2848 *
2849 * This will re-activate the suspended device, increasing power usage
2850 * while letting drivers communicate again with its endpoints.
2851 * USB resume explicitly guarantees that the power session between
2852 * the host and the device is the same as it was when the device
2853 * suspended.
2854 *
2855 * If @udev->reset_resume is set then this routine won't check that the
2856 * port is still enabled.  Furthermore, finish_port_resume() above will
2857 * reset @udev.  The end result is that a broken power session can be
2858 * recovered and @udev will appear to persist across a loss of VBUS power.
2859 *
2860 * For example, if a host controller doesn't maintain VBUS suspend current
2861 * during a system sleep or is reset when the system wakes up, all the USB
2862 * power sessions below it will be broken.  This is especially troublesome
2863 * for mass-storage devices containing mounted filesystems, since the
2864 * device will appear to have disconnected and all the memory mappings
2865 * to it will be lost.  Using the USB_PERSIST facility, the device can be
2866 * made to appear as if it had not disconnected.
2867 *
2868 * This facility can be dangerous.  Although usb_reset_and_verify_device() makes
2869 * every effort to insure that the same device is present after the
2870 * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
2871 * quite possible for a device to remain unaltered but its media to be
2872 * changed.  If the user replaces a flash memory card while the system is
2873 * asleep, he will have only himself to blame when the filesystem on the
2874 * new card is corrupted and the system crashes.
2875 *
2876 * Returns 0 on success, else negative errno.
2877 */
2878int usb_port_resume(struct usb_device *udev, pm_message_t msg)
2879{
2880	struct usb_hub	*hub = hdev_to_hub(udev->parent);
2881	int		port1 = udev->portnum;
2882	int		status;
2883	u16		portchange, portstatus;
2884
2885	/* Skip the initial Clear-Suspend step for a remote wakeup */
2886	status = hub_port_status(hub, port1, &portstatus, &portchange);
2887	if (status == 0 && !port_is_suspended(hub, portstatus))
2888		goto SuspendCleared;
2889
2890	// dev_dbg(hub->intfdev, "resume port %d\n", port1);
2891
2892	set_bit(port1, hub->busy_bits);
2893
2894	/* see 7.1.7.7; affects power usage, but not budgeting */
2895	if (hub_is_superspeed(hub->hdev))
2896		status = set_port_feature(hub->hdev,
2897				port1 | (USB_SS_PORT_LS_U0 << 3),
2898				USB_PORT_FEAT_LINK_STATE);
2899	else
2900		status = clear_port_feature(hub->hdev,
2901				port1, USB_PORT_FEAT_SUSPEND);
2902	if (status) {
2903		dev_dbg(hub->intfdev, "can't resume port %d, status %d\n",
2904				port1, status);
2905	} else {
2906		/* drive resume for at least 20 msec */
2907		dev_dbg(&udev->dev, "usb %sresume\n",
2908				(PMSG_IS_AUTO(msg) ? "auto-" : ""));
2909		msleep(25);
2910
2911		/* Virtual root hubs can trigger on GET_PORT_STATUS to
2912		 * stop resume signaling.  Then finish the resume
2913		 * sequence.
2914		 */
2915		status = hub_port_status(hub, port1, &portstatus, &portchange);
2916
2917		/* TRSMRCY = 10 msec */
2918		msleep(10);
2919	}
2920
2921 SuspendCleared:
2922	if (status == 0) {
2923		if (hub_is_superspeed(hub->hdev)) {
2924			if (portchange & USB_PORT_STAT_C_LINK_STATE)
2925				clear_port_feature(hub->hdev, port1,
2926					USB_PORT_FEAT_C_PORT_LINK_STATE);
2927		} else {
2928			if (portchange & USB_PORT_STAT_C_SUSPEND)
2929				clear_port_feature(hub->hdev, port1,
2930						USB_PORT_FEAT_C_SUSPEND);
2931		}
2932	}
2933
2934	clear_bit(port1, hub->busy_bits);
2935
2936	status = check_port_resume_type(udev,
2937			hub, port1, status, portchange, portstatus);
2938	if (status == 0)
2939		status = finish_port_resume(udev);
2940	if (status < 0) {
2941		dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2942		hub_port_logical_disconnect(hub, port1);
2943	} else  {
2944		/* Try to enable USB2 hardware LPM */
2945		if (udev->usb2_hw_lpm_capable == 1)
2946			usb_set_usb2_hardware_lpm(udev, 1);
2947
2948		/* Try to enable USB3 LPM */
2949		usb_unlocked_enable_lpm(udev);
2950	}
2951
2952	return status;
2953}
2954
2955/* caller has locked udev */
2956int usb_remote_wakeup(struct usb_device *udev)
2957{
2958	int	status = 0;
2959
2960	if (udev->state == USB_STATE_SUSPENDED) {
2961		dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
2962		status = usb_autoresume_device(udev);
2963		if (status == 0) {
2964			/* Let the drivers do their thing, then... */
2965			usb_autosuspend_device(udev);
2966		}
2967	}
2968	return status;
2969}
2970
2971#else	/* CONFIG_USB_SUSPEND */
2972
2973/* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
2974
2975int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
2976{
2977	return 0;
2978}
2979
2980/* However we may need to do a reset-resume */
2981
2982int usb_port_resume(struct usb_device *udev, pm_message_t msg)
2983{
2984	struct usb_hub	*hub = hdev_to_hub(udev->parent);
2985	int		port1 = udev->portnum;
2986	int		status;
2987	u16		portchange, portstatus;
2988
2989	status = hub_port_status(hub, port1, &portstatus, &portchange);
2990	status = check_port_resume_type(udev,
2991			hub, port1, status, portchange, portstatus);
2992
2993	if (status) {
2994		dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2995		hub_port_logical_disconnect(hub, port1);
2996	} else if (udev->reset_resume) {
2997		dev_dbg(&udev->dev, "reset-resume\n");
2998		status = usb_reset_and_verify_device(udev);
2999	}
3000	return status;
3001}
3002
3003#endif
3004
3005static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
3006{
3007	struct usb_hub		*hub = usb_get_intfdata (intf);
3008	struct usb_device	*hdev = hub->hdev;
3009	unsigned		port1;
3010	int			status;
3011
3012	/* Warn if children aren't already suspended */
3013	for (port1 = 1; port1 <= hdev->maxchild; port1++) {
3014		struct usb_device	*udev;
3015
3016		udev = hdev->children [port1-1];
3017		if (udev && udev->can_submit) {
3018			dev_warn(&intf->dev, "port %d nyet suspended\n", port1);
3019			if (PMSG_IS_AUTO(msg))
3020				return -EBUSY;
3021		}
3022	}
3023	if (hub_is_superspeed(hdev) && hdev->do_remote_wakeup) {
3024		/* Enable hub to send remote wakeup for all ports. */
3025		for (port1 = 1; port1 <= hdev->maxchild; port1++) {
3026			status = set_port_feature(hdev,
3027					port1 |
3028					USB_PORT_FEAT_REMOTE_WAKE_CONNECT |
3029					USB_PORT_FEAT_REMOTE_WAKE_DISCONNECT |
3030					USB_PORT_FEAT_REMOTE_WAKE_OVER_CURRENT,
3031					USB_PORT_FEAT_REMOTE_WAKE_MASK);
3032		}
3033	}
3034
3035	dev_dbg(&intf->dev, "%s\n", __func__);
3036
3037	/* stop khubd and related activity */
3038	hub_quiesce(hub, HUB_SUSPEND);
3039	return 0;
3040}
3041
3042static int hub_resume(struct usb_interface *intf)
3043{
3044	struct usb_hub *hub = usb_get_intfdata(intf);
3045
3046	dev_dbg(&intf->dev, "%s\n", __func__);
3047	hub_activate(hub, HUB_RESUME);
3048	return 0;
3049}
3050
3051static int hub_reset_resume(struct usb_interface *intf)
3052{
3053	struct usb_hub *hub = usb_get_intfdata(intf);
3054
3055	dev_dbg(&intf->dev, "%s\n", __func__);
3056	hub_activate(hub, HUB_RESET_RESUME);
3057	return 0;
3058}
3059
3060/**
3061 * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
3062 * @rhdev: struct usb_device for the root hub
3063 *
3064 * The USB host controller driver calls this function when its root hub
3065 * is resumed and Vbus power has been interrupted or the controller
3066 * has been reset.  The routine marks @rhdev as having lost power.
3067 * When the hub driver is resumed it will take notice and carry out
3068 * power-session recovery for all the "USB-PERSIST"-enabled child devices;
3069 * the others will be disconnected.
3070 */
3071void usb_root_hub_lost_power(struct usb_device *rhdev)
3072{
3073	dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
3074	rhdev->reset_resume = 1;
3075}
3076EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
3077
3078static const char * const usb3_lpm_names[]  = {
3079	"U0",
3080	"U1",
3081	"U2",
3082	"U3",
3083};
3084
3085/*
3086 * Send a Set SEL control transfer to the device, prior to enabling
3087 * device-initiated U1 or U2.  This lets the device know the exit latencies from
3088 * the time the device initiates a U1 or U2 exit, to the time it will receive a
3089 * packet from the host.
3090 *
3091 * This function will fail if the SEL or PEL values for udev are greater than
3092 * the maximum allowed values for the link state to be enabled.
3093 */
3094static int usb_req_set_sel(struct usb_device *udev, enum usb3_link_state state)
3095{
3096	struct usb_set_sel_req *sel_values;
3097	unsigned long long u1_sel;
3098	unsigned long long u1_pel;
3099	unsigned long long u2_sel;
3100	unsigned long long u2_pel;
3101	int ret;
3102
3103	/* Convert SEL and PEL stored in ns to us */
3104	u1_sel = DIV_ROUND_UP(udev->u1_params.sel, 1000);
3105	u1_pel = DIV_ROUND_UP(udev->u1_params.pel, 1000);
3106	u2_sel = DIV_ROUND_UP(udev->u2_params.sel, 1000);
3107	u2_pel = DIV_ROUND_UP(udev->u2_params.pel, 1000);
3108
3109	/*
3110	 * Make sure that the calculated SEL and PEL values for the link
3111	 * state we're enabling aren't bigger than the max SEL/PEL
3112	 * value that will fit in the SET SEL control transfer.
3113	 * Otherwise the device would get an incorrect idea of the exit
3114	 * latency for the link state, and could start a device-initiated
3115	 * U1/U2 when the exit latencies are too high.
3116	 */
3117	if ((state == USB3_LPM_U1 &&
3118				(u1_sel > USB3_LPM_MAX_U1_SEL_PEL ||
3119				 u1_pel > USB3_LPM_MAX_U1_SEL_PEL)) ||
3120			(state == USB3_LPM_U2 &&
3121			 (u2_sel > USB3_LPM_MAX_U2_SEL_PEL ||
3122			  u2_pel > USB3_LPM_MAX_U2_SEL_PEL))) {
3123		dev_dbg(&udev->dev, "Device-initiated %s disabled due "
3124				"to long SEL %llu ms or PEL %llu ms\n",
3125				usb3_lpm_names[state], u1_sel, u1_pel);
3126		return -EINVAL;
3127	}
3128
3129	/*
3130	 * If we're enabling device-initiated LPM for one link state,
3131	 * but the other link state has a too high SEL or PEL value,
3132	 * just set those values to the max in the Set SEL request.
3133	 */
3134	if (u1_sel > USB3_LPM_MAX_U1_SEL_PEL)
3135		u1_sel = USB3_LPM_MAX_U1_SEL_PEL;
3136
3137	if (u1_pel > USB3_LPM_MAX_U1_SEL_PEL)
3138		u1_pel = USB3_LPM_MAX_U1_SEL_PEL;
3139
3140	if (u2_sel > USB3_LPM_MAX_U2_SEL_PEL)
3141		u2_sel = USB3_LPM_MAX_U2_SEL_PEL;
3142
3143	if (u2_pel > USB3_LPM_MAX_U2_SEL_PEL)
3144		u2_pel = USB3_LPM_MAX_U2_SEL_PEL;
3145
3146	/*
3147	 * usb_enable_lpm() can be called as part of a failed device reset,
3148	 * which may be initiated by an error path of a mass storage driver.
3149	 * Therefore, use GFP_NOIO.
3150	 */
3151	sel_values = kmalloc(sizeof *(sel_values), GFP_NOIO);
3152	if (!sel_values)
3153		return -ENOMEM;
3154
3155	sel_values->u1_sel = u1_sel;
3156	sel_values->u1_pel = u1_pel;
3157	sel_values->u2_sel = cpu_to_le16(u2_sel);
3158	sel_values->u2_pel = cpu_to_le16(u2_pel);
3159
3160	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3161			USB_REQ_SET_SEL,
3162			USB_RECIP_DEVICE,
3163			0, 0,
3164			sel_values, sizeof *(sel_values),
3165			USB_CTRL_SET_TIMEOUT);
3166	kfree(sel_values);
3167	return ret;
3168}
3169
3170/*
3171 * Enable or disable device-initiated U1 or U2 transitions.
3172 */
3173static int usb_set_device_initiated_lpm(struct usb_device *udev,
3174		enum usb3_link_state state, bool enable)
3175{
3176	int ret;
3177	int feature;
3178
3179	switch (state) {
3180	case USB3_LPM_U1:
3181		feature = USB_DEVICE_U1_ENABLE;
3182		break;
3183	case USB3_LPM_U2:
3184		feature = USB_DEVICE_U2_ENABLE;
3185		break;
3186	default:
3187		dev_warn(&udev->dev, "%s: Can't %s non-U1 or U2 state.\n",
3188				__func__, enable ? "enable" : "disable");
3189		return -EINVAL;
3190	}
3191
3192	if (udev->state != USB_STATE_CONFIGURED) {
3193		dev_dbg(&udev->dev, "%s: Can't %s %s state "
3194				"for unconfigured device.\n",
3195				__func__, enable ? "enable" : "disable",
3196				usb3_lpm_names[state]);
3197		return 0;
3198	}
3199
3200	if (enable) {
3201		/*
3202		 * First, let the device know about the exit latencies
3203		 * associated with the link state we're about to enable.
3204		 */
3205		ret = usb_req_set_sel(udev, state);
3206		if (ret < 0) {
3207			dev_warn(&udev->dev, "Set SEL for device-initiated "
3208					"%s failed.\n", usb3_lpm_names[state]);
3209			return -EBUSY;
3210		}
3211		/*
3212		 * Now send the control transfer to enable device-initiated LPM
3213		 * for either U1 or U2.
3214		 */
3215		ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3216				USB_REQ_SET_FEATURE,
3217				USB_RECIP_DEVICE,
3218				feature,
3219				0, NULL, 0,
3220				USB_CTRL_SET_TIMEOUT);
3221	} else {
3222		ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3223				USB_REQ_CLEAR_FEATURE,
3224				USB_RECIP_DEVICE,
3225				feature,
3226				0, NULL, 0,
3227				USB_CTRL_SET_TIMEOUT);
3228	}
3229	if (ret < 0) {
3230		dev_warn(&udev->dev, "%s of device-initiated %s failed.\n",
3231				enable ? "Enable" : "Disable",
3232				usb3_lpm_names[state]);
3233		return -EBUSY;
3234	}
3235	return 0;
3236}
3237
3238static int usb_set_lpm_timeout(struct usb_device *udev,
3239		enum usb3_link_state state, int timeout)
3240{
3241	int ret;
3242	int feature;
3243
3244	switch (state) {
3245	case USB3_LPM_U1:
3246		feature = USB_PORT_FEAT_U1_TIMEOUT;
3247		break;
3248	case USB3_LPM_U2:
3249		feature = USB_PORT_FEAT_U2_TIMEOUT;
3250		break;
3251	default:
3252		dev_warn(&udev->dev, "%s: Can't set timeout for non-U1 or U2 state.\n",
3253				__func__);
3254		return -EINVAL;
3255	}
3256
3257	if (state == USB3_LPM_U1 && timeout > USB3_LPM_U1_MAX_TIMEOUT &&
3258			timeout != USB3_LPM_DEVICE_INITIATED) {
3259		dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x, "
3260				"which is a reserved value.\n",
3261				usb3_lpm_names[state], timeout);
3262		return -EINVAL;
3263	}
3264
3265	ret = set_port_feature(udev->parent,
3266			USB_PORT_LPM_TIMEOUT(timeout) | udev->portnum,
3267			feature);
3268	if (ret < 0) {
3269		dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x,"
3270				"error code %i\n", usb3_lpm_names[state],
3271				timeout, ret);
3272		return -EBUSY;
3273	}
3274	if (state == USB3_LPM_U1)
3275		udev->u1_params.timeout = timeout;
3276	else
3277		udev->u2_params.timeout = timeout;
3278	return 0;
3279}
3280
3281/*
3282 * Enable the hub-initiated U1/U2 idle timeouts, and enable device-initiated
3283 * U1/U2 entry.
3284 *
3285 * We will attempt to enable U1 or U2, but there are no guarantees that the
3286 * control transfers to set the hub timeout or enable device-initiated U1/U2
3287 * will be successful.
3288 *
3289 * If we cannot set the parent hub U1/U2 timeout, we attempt to let the xHCI
3290 * driver know about it.  If that call fails, it should be harmless, and just
3291 * take up more slightly more bus bandwidth for unnecessary U1/U2 exit latency.
3292 */
3293static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
3294		enum usb3_link_state state)
3295{
3296	int timeout;
3297
3298	/* We allow the host controller to set the U1/U2 timeout internally
3299	 * first, so that it can change its schedule to account for the
3300	 * additional latency to send data to a device in a lower power
3301	 * link state.
3302	 */
3303	timeout = hcd->driver->enable_usb3_lpm_timeout(hcd, udev, state);
3304
3305	/* xHCI host controller doesn't want to enable this LPM state. */
3306	if (timeout == 0)
3307		return;
3308
3309	if (timeout < 0) {
3310		dev_warn(&udev->dev, "Could not enable %s link state, "
3311				"xHCI error %i.\n", usb3_lpm_names[state],
3312				timeout);
3313		return;
3314	}
3315
3316	if (usb_set_lpm_timeout(udev, state, timeout))
3317		/* If we can't set the parent hub U1/U2 timeout,
3318		 * device-initiated LPM won't be allowed either, so let the xHCI
3319		 * host know that this link state won't be enabled.
3320		 */
3321		hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
3322
3323	/* Only a configured device will accept the Set Feature U1/U2_ENABLE */
3324	else if (udev->actconfig)
3325		usb_set_device_initiated_lpm(udev, state, true);
3326
3327}
3328
3329/*
3330 * Disable the hub-initiated U1/U2 idle timeouts, and disable device-initiated
3331 * U1/U2 entry.
3332 *
3333 * If this function returns -EBUSY, the parent hub will still allow U1/U2 entry.
3334 * If zero is returned, the parent will not allow the link to go into U1/U2.
3335 *
3336 * If zero is returned, device-initiated U1/U2 entry may still be enabled, but
3337 * it won't have an effect on the bus link state because the parent hub will
3338 * still disallow device-initiated U1/U2 entry.
3339 *
3340 * If zero is returned, the xHCI host controller may still think U1/U2 entry is
3341 * possible.  The result will be slightly more bus bandwidth will be taken up
3342 * (to account for U1/U2 exit latency), but it should be harmless.
3343 */
3344static int usb_disable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
3345		enum usb3_link_state state)
3346{
3347	int feature;
3348
3349	switch (state) {
3350	case USB3_LPM_U1:
3351		feature = USB_PORT_FEAT_U1_TIMEOUT;
3352		break;
3353	case USB3_LPM_U2:
3354		feature = USB_PORT_FEAT_U2_TIMEOUT;
3355		break;
3356	default:
3357		dev_warn(&udev->dev, "%s: Can't disable non-U1 or U2 state.\n",
3358				__func__);
3359		return -EINVAL;
3360	}
3361
3362	if (usb_set_lpm_timeout(udev, state, 0))
3363		return -EBUSY;
3364
3365	usb_set_device_initiated_lpm(udev, state, false);
3366
3367	if (hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state))
3368		dev_warn(&udev->dev, "Could not disable xHCI %s timeout, "
3369				"bus schedule bandwidth may be impacted.\n",
3370				usb3_lpm_names[state]);
3371	return 0;
3372}
3373
3374/*
3375 * Disable hub-initiated and device-initiated U1 and U2 entry.
3376 * Caller must own the bandwidth_mutex.
3377 *
3378 * This will call usb_enable_lpm() on failure, which will decrement
3379 * lpm_disable_count, and will re-enable LPM if lpm_disable_count reaches zero.
3380 */
3381int usb_disable_lpm(struct usb_device *udev)
3382{
3383	struct usb_hcd *hcd;
3384
3385	if (!udev || !udev->parent ||
3386			udev->speed != USB_SPEED_SUPER ||
3387			!udev->lpm_capable)
3388		return 0;
3389
3390	hcd = bus_to_hcd(udev->bus);
3391	if (!hcd || !hcd->driver->disable_usb3_lpm_timeout)
3392		return 0;
3393
3394	udev->lpm_disable_count++;
3395	if ((udev->u1_params.timeout == 0 && udev->u2_params.timeout == 0))
3396		return 0;
3397
3398	/* If LPM is enabled, attempt to disable it. */
3399	if (usb_disable_link_state(hcd, udev, USB3_LPM_U1))
3400		goto enable_lpm;
3401	if (usb_disable_link_state(hcd, udev, USB3_LPM_U2))
3402		goto enable_lpm;
3403
3404	return 0;
3405
3406enable_lpm:
3407	usb_enable_lpm(udev);
3408	return -EBUSY;
3409}
3410EXPORT_SYMBOL_GPL(usb_disable_lpm);
3411
3412/* Grab the bandwidth_mutex before calling usb_disable_lpm() */
3413int usb_unlocked_disable_lpm(struct usb_device *udev)
3414{
3415	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3416	int ret;
3417
3418	if (!hcd)
3419		return -EINVAL;
3420
3421	mutex_lock(hcd->bandwidth_mutex);
3422	ret = usb_disable_lpm(udev);
3423	mutex_unlock(hcd->bandwidth_mutex);
3424
3425	return ret;
3426}
3427EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
3428
3429/*
3430 * Attempt to enable device-initiated and hub-initiated U1 and U2 entry.  The
3431 * xHCI host policy may prevent U1 or U2 from being enabled.
3432 *
3433 * Other callers may have disabled link PM, so U1 and U2 entry will be disabled
3434 * until the lpm_disable_count drops to zero.  Caller must own the
3435 * bandwidth_mutex.
3436 */
3437void usb_enable_lpm(struct usb_device *udev)
3438{
3439	struct usb_hcd *hcd;
3440
3441	if (!udev || !udev->parent ||
3442			udev->speed != USB_SPEED_SUPER ||
3443			!udev->lpm_capable)
3444		return;
3445
3446	udev->lpm_disable_count--;
3447	hcd = bus_to_hcd(udev->bus);
3448	/* Double check that we can both enable and disable LPM.
3449	 * Device must be configured to accept set feature U1/U2 timeout.
3450	 */
3451	if (!hcd || !hcd->driver->enable_usb3_lpm_timeout ||
3452			!hcd->driver->disable_usb3_lpm_timeout)
3453		return;
3454
3455	if (udev->lpm_disable_count > 0)
3456		return;
3457
3458	usb_enable_link_state(hcd, udev, USB3_LPM_U1);
3459	usb_enable_link_state(hcd, udev, USB3_LPM_U2);
3460}
3461EXPORT_SYMBOL_GPL(usb_enable_lpm);
3462
3463/* Grab the bandwidth_mutex before calling usb_enable_lpm() */
3464void usb_unlocked_enable_lpm(struct usb_device *udev)
3465{
3466	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3467
3468	if (!hcd)
3469		return;
3470
3471	mutex_lock(hcd->bandwidth_mutex);
3472	usb_enable_lpm(udev);
3473	mutex_unlock(hcd->bandwidth_mutex);
3474}
3475EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
3476
3477
3478#else	/* CONFIG_PM */
3479
3480#define hub_suspend		NULL
3481#define hub_resume		NULL
3482#define hub_reset_resume	NULL
3483
3484int usb_disable_lpm(struct usb_device *udev)
3485{
3486	return 0;
3487}
3488EXPORT_SYMBOL_GPL(usb_disable_lpm);
3489
3490void usb_enable_lpm(struct usb_device *udev) { }
3491EXPORT_SYMBOL_GPL(usb_enable_lpm);
3492
3493int usb_unlocked_disable_lpm(struct usb_device *udev)
3494{
3495	return 0;
3496}
3497EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
3498
3499void usb_unlocked_enable_lpm(struct usb_device *udev) { }
3500EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
3501#endif
3502
3503
3504/* USB 2.0 spec, 7.1.7.3 / fig 7-29:
3505 *
3506 * Between connect detection and reset signaling there must be a delay
3507 * of 100ms at least for debounce and power-settling.  The corresponding
3508 * timer shall restart whenever the downstream port detects a disconnect.
3509 * 
3510 * Apparently there are some bluetooth and irda-dongles and a number of
3511 * low-speed devices for which this debounce period may last over a second.
3512 * Not covered by the spec - but easy to deal with.
3513 *
3514 * This implementation uses a 1500ms total debounce timeout; if the
3515 * connection isn't stable by then it returns -ETIMEDOUT.  It checks
3516 * every 25ms for transient disconnects.  When the port status has been
3517 * unchanged for 100ms it returns the port status.
3518 */
3519static int hub_port_debounce(struct usb_hub *hub, int port1)
3520{
3521	int ret;
3522	int total_time, stable_time = 0;
3523	u16 portchange, portstatus;
3524	unsigned connection = 0xffff;
3525
3526	for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
3527		ret = hub_port_status(hub, port1, &portstatus, &portchange);
3528		if (ret < 0)
3529			return ret;
3530
3531		if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
3532		     (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
3533			stable_time += HUB_DEBOUNCE_STEP;
3534			if (stable_time >= HUB_DEBOUNCE_STABLE)
3535				break;
3536		} else {
3537			stable_time = 0;
3538			connection = portstatus & USB_PORT_STAT_CONNECTION;
3539		}
3540
3541		if (portchange & USB_PORT_STAT_C_CONNECTION) {
3542			clear_port_feature(hub->hdev, port1,
3543					USB_PORT_FEAT_C_CONNECTION);
3544		}
3545
3546		if (total_time >= HUB_DEBOUNCE_TIMEOUT)
3547			break;
3548		msleep(HUB_DEBOUNCE_STEP);
3549	}
3550
3551	dev_dbg (hub->intfdev,
3552		"debounce: port %d: total %dms stable %dms status 0x%x\n",
3553		port1, total_time, stable_time, portstatus);
3554
3555	if (stable_time < HUB_DEBOUNCE_STABLE)
3556		return -ETIMEDOUT;
3557	return portstatus;
3558}
3559
3560void usb_ep0_reinit(struct usb_device *udev)
3561{
3562	usb_disable_endpoint(udev, 0 + USB_DIR_IN, true);
3563	usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true);
3564	usb_enable_endpoint(udev, &udev->ep0, true);
3565}
3566EXPORT_SYMBOL_GPL(usb_ep0_reinit);
3567
3568#define usb_sndaddr0pipe()	(PIPE_CONTROL << 30)
3569#define usb_rcvaddr0pipe()	((PIPE_CONTROL << 30) | USB_DIR_IN)
3570
3571static int hub_set_address(struct usb_device *udev, int devnum)
3572{
3573	int retval;
3574	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3575
3576	/*
3577	 * The host controller will choose the device address,
3578	 * instead of the core having chosen it earlier
3579	 */
3580	if (!hcd->driver->address_device && devnum <= 1)
3581		return -EINVAL;
3582	if (udev->state == USB_STATE_ADDRESS)
3583		return 0;
3584	if (udev->state != USB_STATE_DEFAULT)
3585		return -EINVAL;
3586	if (hcd->driver->address_device)
3587		retval = hcd->driver->address_device(hcd, udev);
3588	else
3589		retval = usb_control_msg(udev, usb_sndaddr0pipe(),
3590				USB_REQ_SET_ADDRESS, 0, devnum, 0,
3591				NULL, 0, USB_CTRL_SET_TIMEOUT);
3592	if (retval == 0) {
3593		update_devnum(udev, devnum);
3594		/* Device now using proper address. */
3595		usb_set_device_state(udev, USB_STATE_ADDRESS);
3596		usb_ep0_reinit(udev);
3597	}
3598	return retval;
3599}
3600
3601/* Reset device, (re)assign address, get device descriptor.
3602 * Device connection must be stable, no more debouncing needed.
3603 * Returns device in USB_STATE_ADDRESS, except on error.
3604 *
3605 * If this is called for an already-existing device (as part of
3606 * usb_reset_and_verify_device), the caller must own the device lock.  For a
3607 * newly detected device that is not accessible through any global
3608 * pointers, it's not necessary to lock the device.
3609 */
3610static int
3611hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
3612		int retry_counter)
3613{
3614	static DEFINE_MUTEX(usb_address0_mutex);
3615
3616	struct usb_device	*hdev = hub->hdev;
3617	struct usb_hcd		*hcd = bus_to_hcd(hdev->bus);
3618	int			i, j, retval;
3619	unsigned		delay = HUB_SHORT_RESET_TIME;
3620	enum usb_device_speed	oldspeed = udev->speed;
3621	const char		*speed;
3622	int			devnum = udev->devnum;
3623
3624	/* root hub ports have a slightly longer reset period
3625	 * (from USB 2.0 spec, section 7.1.7.5)
3626	 */
3627	if (!hdev->parent) {
3628		delay = HUB_ROOT_RESET_TIME;
3629		if (port1 == hdev->bus->otg_port)
3630			hdev->bus->b_hnp_enable = 0;
3631	}
3632
3633	/* Some low speed devices have problems with the quick delay, so */
3634	/*  be a bit pessimistic with those devices. RHbug #23670 */
3635	if (oldspeed == USB_SPEED_LOW)
3636		delay = HUB_LONG_RESET_TIME;
3637
3638	mutex_lock(&usb_address0_mutex);
3639
3640	/* Reset the device; full speed may morph to high speed */
3641	/* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */
3642	retval = hub_port_reset(hub, port1, udev, delay, false);
3643	if (retval < 0)		/* error or disconnect */
3644		goto fail;
3645	/* success, speed is known */
3646
3647	retval = -ENODEV;
3648
3649	if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
3650		dev_dbg(&udev->dev, "device reset changed speed!\n");
3651		goto fail;
3652	}
3653	oldspeed = udev->speed;
3654
3655	/* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
3656	 * it's fixed size except for full speed devices.
3657	 * For Wireless USB devices, ep0 max packet is always 512 (tho
3658	 * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
3659	 */
3660	switch (udev->speed) {
3661	case USB_SPEED_SUPER:
3662	case USB_SPEED_WIRELESS:	/* fixed at 512 */
3663		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
3664		break;
3665	case USB_SPEED_HIGH:		/* fixed at 64 */
3666		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
3667		break;
3668	case USB_SPEED_FULL:		/* 8, 16, 32, or 64 */
3669		/* to determine the ep0 maxpacket size, try to read
3670		 * the device descriptor to get bMaxPacketSize0 and
3671		 * then correct our initial guess.
3672		 */
3673		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
3674		break;
3675	case USB_SPEED_LOW:		/* fixed at 8 */
3676		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(8);
3677		break;
3678	default:
3679		goto fail;
3680	}
3681
3682	if (udev->speed == USB_SPEED_WIRELESS)
3683		speed = "variable speed Wireless";
3684	else
3685		speed = usb_speed_string(udev->speed);
3686
 
 
 
 
 
 
 
 
 
3687	if (udev->speed != USB_SPEED_SUPER)
3688		dev_info(&udev->dev,
3689				"%s %s USB device number %d using %s\n",
3690				(udev->config) ? "reset" : "new", speed,
3691				devnum, udev->bus->controller->driver->name);
3692
3693	/* Set up TT records, if needed  */
3694	if (hdev->tt) {
3695		udev->tt = hdev->tt;
3696		udev->ttport = hdev->ttport;
3697	} else if (udev->speed != USB_SPEED_HIGH
3698			&& hdev->speed == USB_SPEED_HIGH) {
3699		if (!hub->tt.hub) {
3700			dev_err(&udev->dev, "parent hub has no TT\n");
3701			retval = -EINVAL;
3702			goto fail;
3703		}
3704		udev->tt = &hub->tt;
3705		udev->ttport = port1;
3706	}
3707 
3708	/* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
3709	 * Because device hardware and firmware is sometimes buggy in
3710	 * this area, and this is how Linux has done it for ages.
3711	 * Change it cautiously.
3712	 *
3713	 * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
3714	 * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
3715	 * so it may help with some non-standards-compliant devices.
3716	 * Otherwise we start with SET_ADDRESS and then try to read the
3717	 * first 8 bytes of the device descriptor to get the ep0 maxpacket
3718	 * value.
3719	 */
3720	for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
3721		if (USE_NEW_SCHEME(retry_counter) && !(hcd->driver->flags & HCD_USB3)) {
3722			struct usb_device_descriptor *buf;
3723			int r = 0;
3724
3725#define GET_DESCRIPTOR_BUFSIZE	64
3726			buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
3727			if (!buf) {
3728				retval = -ENOMEM;
3729				continue;
3730			}
3731
3732			/* Retry on all errors; some devices are flakey.
3733			 * 255 is for WUSB devices, we actually need to use
3734			 * 512 (WUSB1.0[4.8.1]).
3735			 */
3736			for (j = 0; j < 3; ++j) {
3737				buf->bMaxPacketSize0 = 0;
3738				r = usb_control_msg(udev, usb_rcvaddr0pipe(),
3739					USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
3740					USB_DT_DEVICE << 8, 0,
3741					buf, GET_DESCRIPTOR_BUFSIZE,
3742					initial_descriptor_timeout);
3743				switch (buf->bMaxPacketSize0) {
3744				case 8: case 16: case 32: case 64: case 255:
3745					if (buf->bDescriptorType ==
3746							USB_DT_DEVICE) {
3747						r = 0;
3748						break;
3749					}
3750					/* FALL THROUGH */
3751				default:
3752					if (r == 0)
3753						r = -EPROTO;
3754					break;
3755				}
3756				if (r == 0)
3757					break;
3758			}
3759			udev->descriptor.bMaxPacketSize0 =
3760					buf->bMaxPacketSize0;
3761			kfree(buf);
3762
3763			retval = hub_port_reset(hub, port1, udev, delay, false);
3764			if (retval < 0)		/* error or disconnect */
3765				goto fail;
3766			if (oldspeed != udev->speed) {
3767				dev_dbg(&udev->dev,
3768					"device reset changed speed!\n");
3769				retval = -ENODEV;
3770				goto fail;
3771			}
3772			if (r) {
3773				dev_err(&udev->dev,
3774					"device descriptor read/64, error %d\n",
3775					r);
3776				retval = -EMSGSIZE;
3777				continue;
3778			}
3779#undef GET_DESCRIPTOR_BUFSIZE
3780		}
3781
3782 		/*
3783 		 * If device is WUSB, we already assigned an
3784 		 * unauthorized address in the Connect Ack sequence;
3785 		 * authorization will assign the final address.
3786 		 */
3787		if (udev->wusb == 0) {
3788			for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
3789				retval = hub_set_address(udev, devnum);
3790				if (retval >= 0)
3791					break;
3792				msleep(200);
3793			}
3794			if (retval < 0) {
3795				dev_err(&udev->dev,
3796					"device not accepting address %d, error %d\n",
3797					devnum, retval);
3798				goto fail;
3799			}
3800			if (udev->speed == USB_SPEED_SUPER) {
3801				devnum = udev->devnum;
3802				dev_info(&udev->dev,
3803						"%s SuperSpeed USB device number %d using %s\n",
3804						(udev->config) ? "reset" : "new",
3805						devnum, udev->bus->controller->driver->name);
3806			}
3807
3808			/* cope with hardware quirkiness:
3809			 *  - let SET_ADDRESS settle, some device hardware wants it
3810			 *  - read ep0 maxpacket even for high and low speed,
3811			 */
3812			msleep(10);
3813			if (USE_NEW_SCHEME(retry_counter) && !(hcd->driver->flags & HCD_USB3))
3814				break;
3815  		}
3816
3817		retval = usb_get_device_descriptor(udev, 8);
3818		if (retval < 8) {
3819			dev_err(&udev->dev,
3820					"device descriptor read/8, error %d\n",
3821					retval);
3822			if (retval >= 0)
3823				retval = -EMSGSIZE;
3824		} else {
3825			retval = 0;
3826			break;
3827		}
3828	}
3829	if (retval)
3830		goto fail;
3831
3832	/*
3833	 * Some superspeed devices have finished the link training process
3834	 * and attached to a superspeed hub port, but the device descriptor
3835	 * got from those devices show they aren't superspeed devices. Warm
3836	 * reset the port attached by the devices can fix them.
3837	 */
3838	if ((udev->speed == USB_SPEED_SUPER) &&
3839			(le16_to_cpu(udev->descriptor.bcdUSB) < 0x0300)) {
3840		dev_err(&udev->dev, "got a wrong device descriptor, "
3841				"warm reset device\n");
3842		hub_port_reset(hub, port1, udev,
3843				HUB_BH_RESET_TIME, true);
3844		retval = -EINVAL;
3845		goto fail;
3846	}
3847
3848	if (udev->descriptor.bMaxPacketSize0 == 0xff ||
3849			udev->speed == USB_SPEED_SUPER)
3850		i = 512;
3851	else
3852		i = udev->descriptor.bMaxPacketSize0;
3853	if (usb_endpoint_maxp(&udev->ep0.desc) != i) {
3854		if (udev->speed == USB_SPEED_LOW ||
3855				!(i == 8 || i == 16 || i == 32 || i == 64)) {
3856			dev_err(&udev->dev, "Invalid ep0 maxpacket: %d\n", i);
3857			retval = -EMSGSIZE;
3858			goto fail;
3859		}
3860		if (udev->speed == USB_SPEED_FULL)
3861			dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
3862		else
3863			dev_warn(&udev->dev, "Using ep0 maxpacket: %d\n", i);
3864		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
3865		usb_ep0_reinit(udev);
3866	}
3867  
3868	retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
3869	if (retval < (signed)sizeof(udev->descriptor)) {
3870		dev_err(&udev->dev, "device descriptor read/all, error %d\n",
3871			retval);
3872		if (retval >= 0)
3873			retval = -ENOMSG;
3874		goto fail;
3875	}
3876
3877	if (udev->wusb == 0 && le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0201) {
3878		retval = usb_get_bos_descriptor(udev);
3879		if (!retval) {
3880			udev->lpm_capable = usb_device_supports_lpm(udev);
3881			usb_set_lpm_parameters(udev);
3882		}
3883	}
3884
3885	retval = 0;
3886	/* notify HCD that we have a device connected and addressed */
3887	if (hcd->driver->update_device)
3888		hcd->driver->update_device(hcd, udev);
3889fail:
3890	if (retval) {
3891		hub_port_disable(hub, port1, 0);
3892		update_devnum(udev, devnum);	/* for disconnect processing */
3893	}
3894	mutex_unlock(&usb_address0_mutex);
3895	return retval;
3896}
3897
3898static void
3899check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
3900{
3901	struct usb_qualifier_descriptor	*qual;
3902	int				status;
3903
3904	qual = kmalloc (sizeof *qual, GFP_KERNEL);
3905	if (qual == NULL)
3906		return;
3907
3908	status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
3909			qual, sizeof *qual);
3910	if (status == sizeof *qual) {
3911		dev_info(&udev->dev, "not running at top speed; "
3912			"connect to a high speed hub\n");
3913		/* hub LEDs are probably harder to miss than syslog */
3914		if (hub->has_indicators) {
3915			hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
3916			schedule_delayed_work (&hub->leds, 0);
3917		}
3918	}
3919	kfree(qual);
3920}
3921
3922static unsigned
3923hub_power_remaining (struct usb_hub *hub)
3924{
3925	struct usb_device *hdev = hub->hdev;
3926	int remaining;
3927	int port1;
3928
3929	if (!hub->limited_power)
3930		return 0;
3931
3932	remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
3933	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
3934		struct usb_device	*udev = hdev->children[port1 - 1];
3935		int			delta;
3936
3937		if (!udev)
3938			continue;
3939
3940		/* Unconfigured devices may not use more than 100mA,
3941		 * or 8mA for OTG ports */
3942		if (udev->actconfig)
3943			delta = udev->actconfig->desc.bMaxPower * 2;
3944		else if (port1 != udev->bus->otg_port || hdev->parent)
3945			delta = 100;
3946		else
3947			delta = 8;
3948		if (delta > hub->mA_per_port)
3949			dev_warn(&udev->dev,
3950				 "%dmA is over %umA budget for port %d!\n",
3951				 delta, hub->mA_per_port, port1);
3952		remaining -= delta;
3953	}
3954	if (remaining < 0) {
3955		dev_warn(hub->intfdev, "%dmA over power budget!\n",
3956			- remaining);
3957		remaining = 0;
3958	}
3959	return remaining;
3960}
3961
3962/* Handle physical or logical connection change events.
3963 * This routine is called when:
3964 * 	a port connection-change occurs;
3965 *	a port enable-change occurs (often caused by EMI);
3966 *	usb_reset_and_verify_device() encounters changed descriptors (as from
3967 *		a firmware download)
3968 * caller already locked the hub
3969 */
3970static void hub_port_connect_change(struct usb_hub *hub, int port1,
3971					u16 portstatus, u16 portchange)
3972{
3973	struct usb_device *hdev = hub->hdev;
3974	struct device *hub_dev = hub->intfdev;
3975	struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
3976	unsigned wHubCharacteristics =
3977			le16_to_cpu(hub->descriptor->wHubCharacteristics);
3978	struct usb_device *udev;
3979	int status, i;
3980
3981	dev_dbg (hub_dev,
3982		"port %d, status %04x, change %04x, %s\n",
3983		port1, portstatus, portchange, portspeed(hub, portstatus));
3984
3985	if (hub->has_indicators) {
3986		set_port_led(hub, port1, HUB_LED_AUTO);
3987		hub->indicator[port1-1] = INDICATOR_AUTO;
3988	}
3989
3990#ifdef	CONFIG_USB_OTG
3991	/* during HNP, don't repeat the debounce */
3992	if (hdev->bus->is_b_host)
3993		portchange &= ~(USB_PORT_STAT_C_CONNECTION |
3994				USB_PORT_STAT_C_ENABLE);
3995#endif
3996
3997	/* Try to resuscitate an existing device */
3998	udev = hdev->children[port1-1];
3999	if ((portstatus & USB_PORT_STAT_CONNECTION) && udev &&
4000			udev->state != USB_STATE_NOTATTACHED) {
4001		usb_lock_device(udev);
4002		if (portstatus & USB_PORT_STAT_ENABLE) {
4003			status = 0;		/* Nothing to do */
4004
4005#ifdef CONFIG_USB_SUSPEND
4006		} else if (udev->state == USB_STATE_SUSPENDED &&
4007				udev->persist_enabled) {
4008			/* For a suspended device, treat this as a
4009			 * remote wakeup event.
4010			 */
4011			status = usb_remote_wakeup(udev);
4012#endif
4013
4014		} else {
4015			status = -ENODEV;	/* Don't resuscitate */
4016		}
4017		usb_unlock_device(udev);
4018
4019		if (status == 0) {
4020			clear_bit(port1, hub->change_bits);
4021			return;
4022		}
4023	}
4024
4025	/* Disconnect any existing devices under this port */
4026	if (udev)
4027		usb_disconnect(&hdev->children[port1-1]);
4028	clear_bit(port1, hub->change_bits);
4029
4030	/* We can forget about a "removed" device when there's a physical
4031	 * disconnect or the connect status changes.
4032	 */
4033	if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
4034			(portchange & USB_PORT_STAT_C_CONNECTION))
4035		clear_bit(port1, hub->removed_bits);
4036
4037	if (portchange & (USB_PORT_STAT_C_CONNECTION |
4038				USB_PORT_STAT_C_ENABLE)) {
4039		status = hub_port_debounce(hub, port1);
4040		if (status < 0) {
4041			if (printk_ratelimit())
4042				dev_err(hub_dev, "connect-debounce failed, "
4043						"port %d disabled\n", port1);
4044			portstatus &= ~USB_PORT_STAT_CONNECTION;
4045		} else {
4046			portstatus = status;
4047		}
4048	}
4049
4050	/* Return now if debouncing failed or nothing is connected or
4051	 * the device was "removed".
4052	 */
4053	if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
4054			test_bit(port1, hub->removed_bits)) {
4055
4056		/* maybe switch power back on (e.g. root hub was reset) */
4057		if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
4058				&& !port_is_power_on(hub, portstatus))
4059			set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
4060
4061		if (portstatus & USB_PORT_STAT_ENABLE)
4062  			goto done;
4063		return;
4064	}
4065
4066	for (i = 0; i < SET_CONFIG_TRIES; i++) {
4067
4068		/* reallocate for each attempt, since references
4069		 * to the previous one can escape in various ways
4070		 */
4071		udev = usb_alloc_dev(hdev, hdev->bus, port1);
4072		if (!udev) {
4073			dev_err (hub_dev,
4074				"couldn't allocate port %d usb_device\n",
4075				port1);
4076			goto done;
4077		}
4078
4079		usb_set_device_state(udev, USB_STATE_POWERED);
4080 		udev->bus_mA = hub->mA_per_port;
4081		udev->level = hdev->level + 1;
4082		udev->wusb = hub_is_wusb(hub);
4083
4084		/* Only USB 3.0 devices are connected to SuperSpeed hubs. */
4085		if (hub_is_superspeed(hub->hdev))
4086			udev->speed = USB_SPEED_SUPER;
4087		else
4088			udev->speed = USB_SPEED_UNKNOWN;
4089
4090		choose_devnum(udev);
4091		if (udev->devnum <= 0) {
4092			status = -ENOTCONN;	/* Don't retry */
4093			goto loop;
4094		}
4095
4096		/* reset (non-USB 3.0 devices) and get descriptor */
4097		status = hub_port_init(hub, udev, port1, i);
4098		if (status < 0)
4099			goto loop;
4100
4101		usb_detect_quirks(udev);
4102		if (udev->quirks & USB_QUIRK_DELAY_INIT)
4103			msleep(1000);
4104
4105		/* consecutive bus-powered hubs aren't reliable; they can
4106		 * violate the voltage drop budget.  if the new child has
4107		 * a "powered" LED, users should notice we didn't enable it
4108		 * (without reading syslog), even without per-port LEDs
4109		 * on the parent.
4110		 */
4111		if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
4112				&& udev->bus_mA <= 100) {
4113			u16	devstat;
4114
4115			status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
4116					&devstat);
4117			if (status < 2) {
4118				dev_dbg(&udev->dev, "get status %d ?\n", status);
4119				goto loop_disable;
4120			}
4121			le16_to_cpus(&devstat);
4122			if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
4123				dev_err(&udev->dev,
4124					"can't connect bus-powered hub "
4125					"to this port\n");
4126				if (hub->has_indicators) {
4127					hub->indicator[port1-1] =
4128						INDICATOR_AMBER_BLINK;
4129					schedule_delayed_work (&hub->leds, 0);
4130				}
4131				status = -ENOTCONN;	/* Don't retry */
4132				goto loop_disable;
4133			}
4134		}
4135 
4136		/* check for devices running slower than they could */
4137		if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
4138				&& udev->speed == USB_SPEED_FULL
4139				&& highspeed_hubs != 0)
4140			check_highspeed (hub, udev, port1);
4141
4142		/* Store the parent's children[] pointer.  At this point
4143		 * udev becomes globally accessible, although presumably
4144		 * no one will look at it until hdev is unlocked.
4145		 */
4146		status = 0;
4147
4148		/* We mustn't add new devices if the parent hub has
4149		 * been disconnected; we would race with the
4150		 * recursively_mark_NOTATTACHED() routine.
4151		 */
4152		spin_lock_irq(&device_state_lock);
4153		if (hdev->state == USB_STATE_NOTATTACHED)
4154			status = -ENOTCONN;
4155		else
4156			hdev->children[port1-1] = udev;
4157		spin_unlock_irq(&device_state_lock);
4158
4159		/* Run it through the hoops (find a driver, etc) */
4160		if (!status) {
4161			status = usb_new_device(udev);
4162			if (status) {
4163				spin_lock_irq(&device_state_lock);
4164				hdev->children[port1-1] = NULL;
4165				spin_unlock_irq(&device_state_lock);
4166			}
4167		}
4168
4169		if (status)
4170			goto loop_disable;
4171
4172		status = hub_power_remaining(hub);
4173		if (status)
4174			dev_dbg(hub_dev, "%dmA power budget left\n", status);
4175
4176		return;
4177
4178loop_disable:
4179		hub_port_disable(hub, port1, 1);
4180loop:
4181		usb_ep0_reinit(udev);
4182		release_devnum(udev);
4183		hub_free_dev(udev);
4184		usb_put_dev(udev);
4185		if ((status == -ENOTCONN) || (status == -ENOTSUPP))
4186			break;
4187	}
4188	if (hub->hdev->parent ||
4189			!hcd->driver->port_handed_over ||
4190			!(hcd->driver->port_handed_over)(hcd, port1))
4191		dev_err(hub_dev, "unable to enumerate USB device on port %d\n",
4192				port1);
4193 
4194done:
4195	hub_port_disable(hub, port1, 1);
4196	if (hcd->driver->relinquish_port && !hub->hdev->parent)
4197		hcd->driver->relinquish_port(hcd, port1);
4198}
4199
4200/* Returns 1 if there was a remote wakeup and a connect status change. */
4201static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
4202		u16 portstatus, u16 portchange)
4203{
4204	struct usb_device *hdev;
4205	struct usb_device *udev;
4206	int connect_change = 0;
4207	int ret;
4208
4209	hdev = hub->hdev;
4210	udev = hdev->children[port-1];
4211	if (!hub_is_superspeed(hdev)) {
4212		if (!(portchange & USB_PORT_STAT_C_SUSPEND))
4213			return 0;
4214		clear_port_feature(hdev, port, USB_PORT_FEAT_C_SUSPEND);
4215	} else {
4216		if (!udev || udev->state != USB_STATE_SUSPENDED ||
4217				 (portstatus & USB_PORT_STAT_LINK_STATE) !=
4218				 USB_SS_PORT_LS_U0)
4219			return 0;
4220	}
4221
4222	if (udev) {
4223		/* TRSMRCY = 10 msec */
4224		msleep(10);
4225
4226		usb_lock_device(udev);
4227		ret = usb_remote_wakeup(udev);
4228		usb_unlock_device(udev);
4229		if (ret < 0)
4230			connect_change = 1;
4231	} else {
4232		ret = -ENODEV;
4233		hub_port_disable(hub, port, 1);
4234	}
4235	dev_dbg(hub->intfdev, "resume on port %d, status %d\n",
4236			port, ret);
4237	return connect_change;
4238}
4239
4240static void hub_events(void)
4241{
4242	struct list_head *tmp;
4243	struct usb_device *hdev;
4244	struct usb_interface *intf;
4245	struct usb_hub *hub;
4246	struct device *hub_dev;
4247	u16 hubstatus;
4248	u16 hubchange;
4249	u16 portstatus;
4250	u16 portchange;
4251	int i, ret;
4252	int connect_change, wakeup_change;
4253
4254	/*
4255	 *  We restart the list every time to avoid a deadlock with
4256	 * deleting hubs downstream from this one. This should be
4257	 * safe since we delete the hub from the event list.
4258	 * Not the most efficient, but avoids deadlocks.
4259	 */
4260	while (1) {
4261
4262		/* Grab the first entry at the beginning of the list */
4263		spin_lock_irq(&hub_event_lock);
4264		if (list_empty(&hub_event_list)) {
4265			spin_unlock_irq(&hub_event_lock);
4266			break;
4267		}
4268
4269		tmp = hub_event_list.next;
4270		list_del_init(tmp);
4271
4272		hub = list_entry(tmp, struct usb_hub, event_list);
4273		kref_get(&hub->kref);
4274		spin_unlock_irq(&hub_event_lock);
4275
4276		hdev = hub->hdev;
4277		hub_dev = hub->intfdev;
4278		intf = to_usb_interface(hub_dev);
4279		dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
4280				hdev->state, hub->descriptor
4281					? hub->descriptor->bNbrPorts
4282					: 0,
4283				/* NOTE: expects max 15 ports... */
4284				(u16) hub->change_bits[0],
4285				(u16) hub->event_bits[0]);
4286
4287		/* Lock the device, then check to see if we were
4288		 * disconnected while waiting for the lock to succeed. */
4289		usb_lock_device(hdev);
4290		if (unlikely(hub->disconnected))
4291			goto loop_disconnected;
4292
4293		/* If the hub has died, clean up after it */
4294		if (hdev->state == USB_STATE_NOTATTACHED) {
4295			hub->error = -ENODEV;
4296			hub_quiesce(hub, HUB_DISCONNECT);
4297			goto loop;
4298		}
4299
4300		/* Autoresume */
4301		ret = usb_autopm_get_interface(intf);
4302		if (ret) {
4303			dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
4304			goto loop;
4305		}
4306
4307		/* If this is an inactive hub, do nothing */
4308		if (hub->quiescing)
4309			goto loop_autopm;
4310
4311		if (hub->error) {
4312			dev_dbg (hub_dev, "resetting for error %d\n",
4313				hub->error);
4314
4315			ret = usb_reset_device(hdev);
4316			if (ret) {
4317				dev_dbg (hub_dev,
4318					"error resetting hub: %d\n", ret);
4319				goto loop_autopm;
4320			}
4321
4322			hub->nerrors = 0;
4323			hub->error = 0;
4324		}
4325
4326		/* deal with port status changes */
4327		for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
4328			if (test_bit(i, hub->busy_bits))
4329				continue;
4330			connect_change = test_bit(i, hub->change_bits);
4331			wakeup_change = test_and_clear_bit(i, hub->wakeup_bits);
4332			if (!test_and_clear_bit(i, hub->event_bits) &&
4333					!connect_change && !wakeup_change)
4334				continue;
4335
4336			ret = hub_port_status(hub, i,
4337					&portstatus, &portchange);
4338			if (ret < 0)
4339				continue;
4340
4341			if (portchange & USB_PORT_STAT_C_CONNECTION) {
4342				clear_port_feature(hdev, i,
4343					USB_PORT_FEAT_C_CONNECTION);
4344				connect_change = 1;
4345			}
4346
4347			if (portchange & USB_PORT_STAT_C_ENABLE) {
4348				if (!connect_change)
4349					dev_dbg (hub_dev,
4350						"port %d enable change, "
4351						"status %08x\n",
4352						i, portstatus);
4353				clear_port_feature(hdev, i,
4354					USB_PORT_FEAT_C_ENABLE);
4355
4356				/*
4357				 * EM interference sometimes causes badly
4358				 * shielded USB devices to be shutdown by
4359				 * the hub, this hack enables them again.
4360				 * Works at least with mouse driver. 
4361				 */
4362				if (!(portstatus & USB_PORT_STAT_ENABLE)
4363				    && !connect_change
4364				    && hdev->children[i-1]) {
4365					dev_err (hub_dev,
4366					    "port %i "
4367					    "disabled by hub (EMI?), "
4368					    "re-enabling...\n",
4369						i);
4370					connect_change = 1;
4371				}
4372			}
4373
4374			if (hub_handle_remote_wakeup(hub, i,
4375						portstatus, portchange))
4376				connect_change = 1;
4377
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4378			if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
4379				u16 status = 0;
4380				u16 unused;
4381
4382				dev_dbg(hub_dev, "over-current change on port "
4383					"%d\n", i);
4384				clear_port_feature(hdev, i,
4385					USB_PORT_FEAT_C_OVER_CURRENT);
4386				msleep(100);	/* Cool down */
4387				hub_power_on(hub, true);
4388				hub_port_status(hub, i, &status, &unused);
4389				if (status & USB_PORT_STAT_OVERCURRENT)
4390					dev_err(hub_dev, "over-current "
4391						"condition on port %d\n", i);
4392			}
4393
4394			if (portchange & USB_PORT_STAT_C_RESET) {
4395				dev_dbg (hub_dev,
4396					"reset change on port %d\n",
4397					i);
4398				clear_port_feature(hdev, i,
4399					USB_PORT_FEAT_C_RESET);
4400			}
4401			if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
4402					hub_is_superspeed(hub->hdev)) {
4403				dev_dbg(hub_dev,
4404					"warm reset change on port %d\n",
4405					i);
4406				clear_port_feature(hdev, i,
4407					USB_PORT_FEAT_C_BH_PORT_RESET);
4408			}
4409			if (portchange & USB_PORT_STAT_C_LINK_STATE) {
4410				clear_port_feature(hub->hdev, i,
4411						USB_PORT_FEAT_C_PORT_LINK_STATE);
4412			}
4413			if (portchange & USB_PORT_STAT_C_CONFIG_ERROR) {
4414				dev_warn(hub_dev,
4415					"config error on port %d\n",
4416					i);
4417				clear_port_feature(hub->hdev, i,
4418						USB_PORT_FEAT_C_PORT_CONFIG_ERROR);
4419			}
4420
4421			/* Warm reset a USB3 protocol port if it's in
4422			 * SS.Inactive state.
4423			 */
4424			if (hub_port_warm_reset_required(hub, portstatus)) {
 
 
4425				dev_dbg(hub_dev, "warm reset port %d\n", i);
4426				hub_port_reset(hub, i, NULL,
4427						HUB_BH_RESET_TIME, true);
4428			}
4429
4430			if (connect_change)
4431				hub_port_connect_change(hub, i,
4432						portstatus, portchange);
4433		} /* end for i */
4434
4435		/* deal with hub status changes */
4436		if (test_and_clear_bit(0, hub->event_bits) == 0)
4437			;	/* do nothing */
4438		else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
4439			dev_err (hub_dev, "get_hub_status failed\n");
4440		else {
4441			if (hubchange & HUB_CHANGE_LOCAL_POWER) {
4442				dev_dbg (hub_dev, "power change\n");
4443				clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
4444				if (hubstatus & HUB_STATUS_LOCAL_POWER)
4445					/* FIXME: Is this always true? */
4446					hub->limited_power = 1;
4447				else
4448					hub->limited_power = 0;
4449			}
4450			if (hubchange & HUB_CHANGE_OVERCURRENT) {
4451				u16 status = 0;
4452				u16 unused;
4453
4454				dev_dbg(hub_dev, "over-current change\n");
4455				clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
4456				msleep(500);	/* Cool down */
4457                        	hub_power_on(hub, true);
4458				hub_hub_status(hub, &status, &unused);
4459				if (status & HUB_STATUS_OVERCURRENT)
4460					dev_err(hub_dev, "over-current "
4461						"condition\n");
4462			}
4463		}
4464
4465 loop_autopm:
4466		/* Balance the usb_autopm_get_interface() above */
4467		usb_autopm_put_interface_no_suspend(intf);
4468 loop:
4469		/* Balance the usb_autopm_get_interface_no_resume() in
4470		 * kick_khubd() and allow autosuspend.
4471		 */
4472		usb_autopm_put_interface(intf);
4473 loop_disconnected:
4474		usb_unlock_device(hdev);
4475		kref_put(&hub->kref, hub_release);
4476
4477        } /* end while (1) */
4478}
4479
4480static int hub_thread(void *__unused)
4481{
4482	/* khubd needs to be freezable to avoid intefering with USB-PERSIST
4483	 * port handover.  Otherwise it might see that a full-speed device
4484	 * was gone before the EHCI controller had handed its port over to
4485	 * the companion full-speed controller.
4486	 */
4487	set_freezable();
4488
4489	do {
4490		hub_events();
4491		wait_event_freezable(khubd_wait,
4492				!list_empty(&hub_event_list) ||
4493				kthread_should_stop());
4494	} while (!kthread_should_stop() || !list_empty(&hub_event_list));
4495
4496	pr_debug("%s: khubd exiting\n", usbcore_name);
4497	return 0;
4498}
4499
4500static const struct usb_device_id hub_id_table[] = {
4501    { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
4502      .bDeviceClass = USB_CLASS_HUB},
4503    { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
4504      .bInterfaceClass = USB_CLASS_HUB},
4505    { }						/* Terminating entry */
4506};
4507
4508MODULE_DEVICE_TABLE (usb, hub_id_table);
4509
4510static struct usb_driver hub_driver = {
4511	.name =		"hub",
4512	.probe =	hub_probe,
4513	.disconnect =	hub_disconnect,
4514	.suspend =	hub_suspend,
4515	.resume =	hub_resume,
4516	.reset_resume =	hub_reset_resume,
4517	.pre_reset =	hub_pre_reset,
4518	.post_reset =	hub_post_reset,
4519	.unlocked_ioctl = hub_ioctl,
4520	.id_table =	hub_id_table,
4521	.supports_autosuspend =	1,
4522};
4523
4524int usb_hub_init(void)
4525{
4526	if (usb_register(&hub_driver) < 0) {
4527		printk(KERN_ERR "%s: can't register hub driver\n",
4528			usbcore_name);
4529		return -1;
4530	}
4531
4532	khubd_task = kthread_run(hub_thread, NULL, "khubd");
4533	if (!IS_ERR(khubd_task))
4534		return 0;
4535
4536	/* Fall through if kernel_thread failed */
4537	usb_deregister(&hub_driver);
4538	printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
4539
4540	return -1;
4541}
4542
4543void usb_hub_cleanup(void)
4544{
4545	kthread_stop(khubd_task);
4546
4547	/*
4548	 * Hub resources are freed for us by usb_deregister. It calls
4549	 * usb_driver_purge on every device which in turn calls that
4550	 * devices disconnect function if it is using this driver.
4551	 * The hub_disconnect function takes care of releasing the
4552	 * individual hub resources. -greg
4553	 */
4554	usb_deregister(&hub_driver);
4555} /* usb_hub_cleanup() */
4556
4557static int descriptors_changed(struct usb_device *udev,
4558		struct usb_device_descriptor *old_device_descriptor)
4559{
4560	int		changed = 0;
4561	unsigned	index;
4562	unsigned	serial_len = 0;
4563	unsigned	len;
4564	unsigned	old_length;
4565	int		length;
4566	char		*buf;
4567
4568	if (memcmp(&udev->descriptor, old_device_descriptor,
4569			sizeof(*old_device_descriptor)) != 0)
4570		return 1;
4571
4572	/* Since the idVendor, idProduct, and bcdDevice values in the
4573	 * device descriptor haven't changed, we will assume the
4574	 * Manufacturer and Product strings haven't changed either.
4575	 * But the SerialNumber string could be different (e.g., a
4576	 * different flash card of the same brand).
4577	 */
4578	if (udev->serial)
4579		serial_len = strlen(udev->serial) + 1;
4580
4581	len = serial_len;
4582	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
4583		old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
4584		len = max(len, old_length);
4585	}
4586
4587	buf = kmalloc(len, GFP_NOIO);
4588	if (buf == NULL) {
4589		dev_err(&udev->dev, "no mem to re-read configs after reset\n");
4590		/* assume the worst */
4591		return 1;
4592	}
4593	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
4594		old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
4595		length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
4596				old_length);
4597		if (length != old_length) {
4598			dev_dbg(&udev->dev, "config index %d, error %d\n",
4599					index, length);
4600			changed = 1;
4601			break;
4602		}
4603		if (memcmp (buf, udev->rawdescriptors[index], old_length)
4604				!= 0) {
4605			dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
4606				index,
4607				((struct usb_config_descriptor *) buf)->
4608					bConfigurationValue);
4609			changed = 1;
4610			break;
4611		}
4612	}
4613
4614	if (!changed && serial_len) {
4615		length = usb_string(udev, udev->descriptor.iSerialNumber,
4616				buf, serial_len);
4617		if (length + 1 != serial_len) {
4618			dev_dbg(&udev->dev, "serial string error %d\n",
4619					length);
4620			changed = 1;
4621		} else if (memcmp(buf, udev->serial, length) != 0) {
4622			dev_dbg(&udev->dev, "serial string changed\n");
4623			changed = 1;
4624		}
4625	}
4626
4627	kfree(buf);
4628	return changed;
4629}
4630
4631/**
4632 * usb_reset_and_verify_device - perform a USB port reset to reinitialize a device
4633 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
4634 *
4635 * WARNING - don't use this routine to reset a composite device
4636 * (one with multiple interfaces owned by separate drivers)!
4637 * Use usb_reset_device() instead.
4638 *
4639 * Do a port reset, reassign the device's address, and establish its
4640 * former operating configuration.  If the reset fails, or the device's
4641 * descriptors change from their values before the reset, or the original
4642 * configuration and altsettings cannot be restored, a flag will be set
4643 * telling khubd to pretend the device has been disconnected and then
4644 * re-connected.  All drivers will be unbound, and the device will be
4645 * re-enumerated and probed all over again.
4646 *
4647 * Returns 0 if the reset succeeded, -ENODEV if the device has been
4648 * flagged for logical disconnection, or some other negative error code
4649 * if the reset wasn't even attempted.
4650 *
4651 * The caller must own the device lock.  For example, it's safe to use
4652 * this from a driver probe() routine after downloading new firmware.
4653 * For calls that might not occur during probe(), drivers should lock
4654 * the device using usb_lock_device_for_reset().
4655 *
4656 * Locking exception: This routine may also be called from within an
4657 * autoresume handler.  Such usage won't conflict with other tasks
4658 * holding the device lock because these tasks should always call
4659 * usb_autopm_resume_device(), thereby preventing any unwanted autoresume.
4660 */
4661static int usb_reset_and_verify_device(struct usb_device *udev)
4662{
4663	struct usb_device		*parent_hdev = udev->parent;
4664	struct usb_hub			*parent_hub;
4665	struct usb_hcd			*hcd = bus_to_hcd(udev->bus);
4666	struct usb_device_descriptor	descriptor = udev->descriptor;
4667	int 				i, ret = 0;
4668	int				port1 = udev->portnum;
4669
4670	if (udev->state == USB_STATE_NOTATTACHED ||
4671			udev->state == USB_STATE_SUSPENDED) {
4672		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
4673				udev->state);
4674		return -EINVAL;
4675	}
4676
4677	if (!parent_hdev) {
4678		/* this requires hcd-specific logic; see ohci_restart() */
4679		dev_dbg(&udev->dev, "%s for root hub!\n", __func__);
4680		return -EISDIR;
4681	}
4682	parent_hub = hdev_to_hub(parent_hdev);
4683
4684	/* Disable LPM while we reset the device and reinstall the alt settings.
4685	 * Device-initiated LPM settings, and system exit latency settings are
4686	 * cleared when the device is reset, so we have to set them up again.
4687	 */
4688	ret = usb_unlocked_disable_lpm(udev);
4689	if (ret) {
4690		dev_err(&udev->dev, "%s Failed to disable LPM\n.", __func__);
4691		goto re_enumerate;
4692	}
4693
4694	set_bit(port1, parent_hub->busy_bits);
4695	for (i = 0; i < SET_CONFIG_TRIES; ++i) {
4696
4697		/* ep0 maxpacket size may change; let the HCD know about it.
4698		 * Other endpoints will be handled by re-enumeration. */
4699		usb_ep0_reinit(udev);
4700		ret = hub_port_init(parent_hub, udev, port1, i);
4701		if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
4702			break;
4703	}
4704	clear_bit(port1, parent_hub->busy_bits);
4705
4706	if (ret < 0)
4707		goto re_enumerate;
4708 
4709	/* Device might have changed firmware (DFU or similar) */
4710	if (descriptors_changed(udev, &descriptor)) {
4711		dev_info(&udev->dev, "device firmware changed\n");
4712		udev->descriptor = descriptor;	/* for disconnect() calls */
4713		goto re_enumerate;
4714  	}
4715
4716	/* Restore the device's previous configuration */
4717	if (!udev->actconfig)
4718		goto done;
4719
4720	mutex_lock(hcd->bandwidth_mutex);
4721	ret = usb_hcd_alloc_bandwidth(udev, udev->actconfig, NULL, NULL);
4722	if (ret < 0) {
4723		dev_warn(&udev->dev,
4724				"Busted HC?  Not enough HCD resources for "
4725				"old configuration.\n");
4726		mutex_unlock(hcd->bandwidth_mutex);
4727		goto re_enumerate;
4728	}
4729	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
4730			USB_REQ_SET_CONFIGURATION, 0,
4731			udev->actconfig->desc.bConfigurationValue, 0,
4732			NULL, 0, USB_CTRL_SET_TIMEOUT);
4733	if (ret < 0) {
4734		dev_err(&udev->dev,
4735			"can't restore configuration #%d (error=%d)\n",
4736			udev->actconfig->desc.bConfigurationValue, ret);
4737		mutex_unlock(hcd->bandwidth_mutex);
4738		goto re_enumerate;
4739  	}
4740	mutex_unlock(hcd->bandwidth_mutex);
4741	usb_set_device_state(udev, USB_STATE_CONFIGURED);
4742
4743	/* Put interfaces back into the same altsettings as before.
4744	 * Don't bother to send the Set-Interface request for interfaces
4745	 * that were already in altsetting 0; besides being unnecessary,
4746	 * many devices can't handle it.  Instead just reset the host-side
4747	 * endpoint state.
4748	 */
4749	for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
4750		struct usb_host_config *config = udev->actconfig;
4751		struct usb_interface *intf = config->interface[i];
4752		struct usb_interface_descriptor *desc;
4753
4754		desc = &intf->cur_altsetting->desc;
4755		if (desc->bAlternateSetting == 0) {
4756			usb_disable_interface(udev, intf, true);
4757			usb_enable_interface(udev, intf, true);
4758			ret = 0;
4759		} else {
4760			/* Let the bandwidth allocation function know that this
4761			 * device has been reset, and it will have to use
4762			 * alternate setting 0 as the current alternate setting.
4763			 */
4764			intf->resetting_device = 1;
4765			ret = usb_set_interface(udev, desc->bInterfaceNumber,
4766					desc->bAlternateSetting);
4767			intf->resetting_device = 0;
4768		}
4769		if (ret < 0) {
4770			dev_err(&udev->dev, "failed to restore interface %d "
4771				"altsetting %d (error=%d)\n",
4772				desc->bInterfaceNumber,
4773				desc->bAlternateSetting,
4774				ret);
4775			goto re_enumerate;
4776		}
4777	}
4778
4779done:
4780	/* Now that the alt settings are re-installed, enable LPM. */
4781	usb_unlocked_enable_lpm(udev);
4782	return 0;
4783 
4784re_enumerate:
4785	/* LPM state doesn't matter when we're about to destroy the device. */
4786	hub_port_logical_disconnect(parent_hub, port1);
4787	return -ENODEV;
4788}
4789
4790/**
4791 * usb_reset_device - warn interface drivers and perform a USB port reset
4792 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
4793 *
4794 * Warns all drivers bound to registered interfaces (using their pre_reset
4795 * method), performs the port reset, and then lets the drivers know that
4796 * the reset is over (using their post_reset method).
4797 *
4798 * Return value is the same as for usb_reset_and_verify_device().
4799 *
4800 * The caller must own the device lock.  For example, it's safe to use
4801 * this from a driver probe() routine after downloading new firmware.
4802 * For calls that might not occur during probe(), drivers should lock
4803 * the device using usb_lock_device_for_reset().
4804 *
4805 * If an interface is currently being probed or disconnected, we assume
4806 * its driver knows how to handle resets.  For all other interfaces,
4807 * if the driver doesn't have pre_reset and post_reset methods then
4808 * we attempt to unbind it and rebind afterward.
4809 */
4810int usb_reset_device(struct usb_device *udev)
4811{
4812	int ret;
4813	int i;
4814	struct usb_host_config *config = udev->actconfig;
4815
4816	if (udev->state == USB_STATE_NOTATTACHED ||
4817			udev->state == USB_STATE_SUSPENDED) {
4818		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
4819				udev->state);
4820		return -EINVAL;
4821	}
4822
4823	/* Prevent autosuspend during the reset */
4824	usb_autoresume_device(udev);
4825
4826	if (config) {
4827		for (i = 0; i < config->desc.bNumInterfaces; ++i) {
4828			struct usb_interface *cintf = config->interface[i];
4829			struct usb_driver *drv;
4830			int unbind = 0;
4831
4832			if (cintf->dev.driver) {
4833				drv = to_usb_driver(cintf->dev.driver);
4834				if (drv->pre_reset && drv->post_reset)
4835					unbind = (drv->pre_reset)(cintf);
4836				else if (cintf->condition ==
4837						USB_INTERFACE_BOUND)
4838					unbind = 1;
4839				if (unbind)
4840					usb_forced_unbind_intf(cintf);
4841			}
4842		}
4843	}
4844
4845	ret = usb_reset_and_verify_device(udev);
4846
4847	if (config) {
4848		for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
4849			struct usb_interface *cintf = config->interface[i];
4850			struct usb_driver *drv;
4851			int rebind = cintf->needs_binding;
4852
4853			if (!rebind && cintf->dev.driver) {
4854				drv = to_usb_driver(cintf->dev.driver);
4855				if (drv->post_reset)
4856					rebind = (drv->post_reset)(cintf);
4857				else if (cintf->condition ==
4858						USB_INTERFACE_BOUND)
4859					rebind = 1;
4860			}
4861			if (ret == 0 && rebind)
4862				usb_rebind_intf(cintf);
4863		}
4864	}
4865
4866	usb_autosuspend_device(udev);
4867	return ret;
4868}
4869EXPORT_SYMBOL_GPL(usb_reset_device);
4870
4871
4872/**
4873 * usb_queue_reset_device - Reset a USB device from an atomic context
4874 * @iface: USB interface belonging to the device to reset
4875 *
4876 * This function can be used to reset a USB device from an atomic
4877 * context, where usb_reset_device() won't work (as it blocks).
4878 *
4879 * Doing a reset via this method is functionally equivalent to calling
4880 * usb_reset_device(), except for the fact that it is delayed to a
4881 * workqueue. This means that any drivers bound to other interfaces
4882 * might be unbound, as well as users from usbfs in user space.
4883 *
4884 * Corner cases:
4885 *
4886 * - Scheduling two resets at the same time from two different drivers
4887 *   attached to two different interfaces of the same device is
4888 *   possible; depending on how the driver attached to each interface
4889 *   handles ->pre_reset(), the second reset might happen or not.
4890 *
4891 * - If a driver is unbound and it had a pending reset, the reset will
4892 *   be cancelled.
4893 *
4894 * - This function can be called during .probe() or .disconnect()
4895 *   times. On return from .disconnect(), any pending resets will be
4896 *   cancelled.
4897 *
4898 * There is no no need to lock/unlock the @reset_ws as schedule_work()
4899 * does its own.
4900 *
4901 * NOTE: We don't do any reference count tracking because it is not
4902 *     needed. The lifecycle of the work_struct is tied to the
4903 *     usb_interface. Before destroying the interface we cancel the
4904 *     work_struct, so the fact that work_struct is queued and or
4905 *     running means the interface (and thus, the device) exist and
4906 *     are referenced.
4907 */
4908void usb_queue_reset_device(struct usb_interface *iface)
4909{
4910	schedule_work(&iface->reset_ws);
4911}
4912EXPORT_SYMBOL_GPL(usb_queue_reset_device);