1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * USB hub driver.
   4 *
   5 * (C) Copyright 1999 Linus Torvalds
   6 * (C) Copyright 1999 Johannes Erdfelt
   7 * (C) Copyright 1999 Gregory P. Smith
   8 * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
   9 *
  10 * Released under the GPLv2 only.
  11 */
  12
  13#include <linux/kernel.h>
  14#include <linux/errno.h>
  15#include <linux/module.h>
  16#include <linux/moduleparam.h>
  17#include <linux/completion.h>
  18#include <linux/sched/mm.h>
  19#include <linux/list.h>
  20#include <linux/slab.h>
  21#include <linux/ioctl.h>
  22#include <linux/usb.h>
  23#include <linux/usbdevice_fs.h>
  24#include <linux/usb/hcd.h>
  25#include <linux/usb/otg.h>
  26#include <linux/usb/quirks.h>
  27#include <linux/workqueue.h>
  28#include <linux/mutex.h>
  29#include <linux/random.h>
  30#include <linux/pm_qos.h>
  31#include <linux/kobject.h>
  32
  33#include <linux/uaccess.h>
  34#include <asm/byteorder.h>
  35
  36#include "hub.h"
  37#include "otg_whitelist.h"
  38
  39#define USB_VENDOR_GENESYS_LOGIC		0x05e3
  40#define HUB_QUIRK_CHECK_PORT_AUTOSUSPEND	0x01
  41
  42#define USB_TP_TRANSMISSION_DELAY	40	/* ns */
  43#define USB_TP_TRANSMISSION_DELAY_MAX	65535	/* ns */
  44
  45/* Protect struct usb_device->state and ->children members
  46 * Note: Both are also protected by ->dev.sem, except that ->state can
  47 * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
  48static DEFINE_SPINLOCK(device_state_lock);
  49
  50/* workqueue to process hub events */
  51static struct workqueue_struct *hub_wq;
  52static void hub_event(struct work_struct *work);
  53
  54/* synchronize hub-port add/remove and peering operations */
  55DEFINE_MUTEX(usb_port_peer_mutex);
  56
  57/* cycle leds on hubs that aren't blinking for attention */
  58static bool blinkenlights;
  59module_param(blinkenlights, bool, S_IRUGO);
  60MODULE_PARM_DESC(blinkenlights, "true to cycle leds on hubs");
  61
  62/*
  63 * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
  64 * 10 seconds to send reply for the initial 64-byte descriptor request.
  65 */
  66/* define initial 64-byte descriptor request timeout in milliseconds */
  67static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
  68module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
  69MODULE_PARM_DESC(initial_descriptor_timeout,
  70		"initial 64-byte descriptor request timeout in milliseconds "
  71		"(default 5000 - 5.0 seconds)");
  72
  73/*
  74 * As of 2.6.10 we introduce a new USB device initialization scheme which
  75 * closely resembles the way Windows works.  Hopefully it will be compatible
  76 * with a wider range of devices than the old scheme.  However some previously
  77 * working devices may start giving rise to "device not accepting address"
  78 * errors; if that happens the user can try the old scheme by adjusting the
  79 * following module parameters.
  80 *
  81 * For maximum flexibility there are two boolean parameters to control the
  82 * hub driver's behavior.  On the first initialization attempt, if the
  83 * "old_scheme_first" parameter is set then the old scheme will be used,
  84 * otherwise the new scheme is used.  If that fails and "use_both_schemes"
  85 * is set, then the driver will make another attempt, using the other scheme.
  86 */
  87static bool old_scheme_first;
  88module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
  89MODULE_PARM_DESC(old_scheme_first,
  90		 "start with the old device initialization scheme");
  91
  92static bool use_both_schemes = 1;
  93module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
  94MODULE_PARM_DESC(use_both_schemes,
  95		"try the other device initialization scheme if the "
  96		"first one fails");
  97
  98/* Mutual exclusion for EHCI CF initialization.  This interferes with
  99 * port reset on some companion controllers.
 100 */
 101DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
 102EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
 103
 104#define HUB_DEBOUNCE_TIMEOUT	2000
 105#define HUB_DEBOUNCE_STEP	  25
 106#define HUB_DEBOUNCE_STABLE	 100
 107
 108static void hub_release(struct kref *kref);
 109static int usb_reset_and_verify_device(struct usb_device *udev);
 110static int hub_port_disable(struct usb_hub *hub, int port1, int set_state);
 111static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
 112		u16 portstatus);
 113
 114static inline char *portspeed(struct usb_hub *hub, int portstatus)
 115{
 116	if (hub_is_superspeedplus(hub->hdev))
 117		return "10.0 Gb/s";
 118	if (hub_is_superspeed(hub->hdev))
 119		return "5.0 Gb/s";
 120	if (portstatus & USB_PORT_STAT_HIGH_SPEED)
 121		return "480 Mb/s";
 122	else if (portstatus & USB_PORT_STAT_LOW_SPEED)
 123		return "1.5 Mb/s";
 124	else
 125		return "12 Mb/s";
 126}
 127
 128/* Note that hdev or one of its children must be locked! */
 129struct usb_hub *usb_hub_to_struct_hub(struct usb_device *hdev)
 130{
 131	if (!hdev || !hdev->actconfig || !hdev->maxchild)
 132		return NULL;
 133	return usb_get_intfdata(hdev->actconfig->interface[0]);
 134}
 135
 136int usb_device_supports_lpm(struct usb_device *udev)
 137{
 138	/* Some devices have trouble with LPM */
 139	if (udev->quirks & USB_QUIRK_NO_LPM)
 140		return 0;
 141
 142	/* USB 2.1 (and greater) devices indicate LPM support through
 143	 * their USB 2.0 Extended Capabilities BOS descriptor.
 144	 */
 145	if (udev->speed == USB_SPEED_HIGH || udev->speed == USB_SPEED_FULL) {
 146		if (udev->bos->ext_cap &&
 147			(USB_LPM_SUPPORT &
 148			 le32_to_cpu(udev->bos->ext_cap->bmAttributes)))
 149			return 1;
 150		return 0;
 151	}
 152
 153	/*
 154	 * According to the USB 3.0 spec, all USB 3.0 devices must support LPM.
 155	 * However, there are some that don't, and they set the U1/U2 exit
 156	 * latencies to zero.
 157	 */
 158	if (!udev->bos->ss_cap) {
 159		dev_info(&udev->dev, "No LPM exit latency info found, disabling LPM.\n");
 160		return 0;
 161	}
 162
 163	if (udev->bos->ss_cap->bU1devExitLat == 0 &&
 164			udev->bos->ss_cap->bU2DevExitLat == 0) {
 165		if (udev->parent)
 166			dev_info(&udev->dev, "LPM exit latency is zeroed, disabling LPM.\n");
 167		else
 168			dev_info(&udev->dev, "We don't know the algorithms for LPM for this host, disabling LPM.\n");
 169		return 0;
 170	}
 171
 172	if (!udev->parent || udev->parent->lpm_capable)
 173		return 1;
 174	return 0;
 175}
 176
 177/*
 178 * Set the Maximum Exit Latency (MEL) for the host to initiate a transition from
 179 * either U1 or U2.
 180 */
 181static void usb_set_lpm_mel(struct usb_device *udev,
 182		struct usb3_lpm_parameters *udev_lpm_params,
 183		unsigned int udev_exit_latency,
 184		struct usb_hub *hub,
 185		struct usb3_lpm_parameters *hub_lpm_params,
 186		unsigned int hub_exit_latency)
 187{
 188	unsigned int total_mel;
 189	unsigned int device_mel;
 190	unsigned int hub_mel;
 191
 192	/*
 193	 * Calculate the time it takes to transition all links from the roothub
 194	 * to the parent hub into U0.  The parent hub must then decode the
 195	 * packet (hub header decode latency) to figure out which port it was
 196	 * bound for.
 197	 *
 198	 * The Hub Header decode latency is expressed in 0.1us intervals (0x1
 199	 * means 0.1us).  Multiply that by 100 to get nanoseconds.
 200	 */
 201	total_mel = hub_lpm_params->mel +
 202		(hub->descriptor->u.ss.bHubHdrDecLat * 100);
 203
 204	/*
 205	 * How long will it take to transition the downstream hub's port into
 206	 * U0?  The greater of either the hub exit latency or the device exit
 207	 * latency.
 208	 *
 209	 * The BOS U1/U2 exit latencies are expressed in 1us intervals.
 210	 * Multiply that by 1000 to get nanoseconds.
 211	 */
 212	device_mel = udev_exit_latency * 1000;
 213	hub_mel = hub_exit_latency * 1000;
 214	if (device_mel > hub_mel)
 215		total_mel += device_mel;
 216	else
 217		total_mel += hub_mel;
 218
 219	udev_lpm_params->mel = total_mel;
 220}
 221
 222/*
 223 * Set the maximum Device to Host Exit Latency (PEL) for the device to initiate
 224 * a transition from either U1 or U2.
 225 */
 226static void usb_set_lpm_pel(struct usb_device *udev,
 227		struct usb3_lpm_parameters *udev_lpm_params,
 228		unsigned int udev_exit_latency,
 229		struct usb_hub *hub,
 230		struct usb3_lpm_parameters *hub_lpm_params,
 231		unsigned int hub_exit_latency,
 232		unsigned int port_to_port_exit_latency)
 233{
 234	unsigned int first_link_pel;
 235	unsigned int hub_pel;
 236
 237	/*
 238	 * First, the device sends an LFPS to transition the link between the
 239	 * device and the parent hub into U0.  The exit latency is the bigger of
 240	 * the device exit latency or the hub exit latency.
 241	 */
 242	if (udev_exit_latency > hub_exit_latency)
 243		first_link_pel = udev_exit_latency * 1000;
 244	else
 245		first_link_pel = hub_exit_latency * 1000;
 246
 247	/*
 248	 * When the hub starts to receive the LFPS, there is a slight delay for
 249	 * it to figure out that one of the ports is sending an LFPS.  Then it
 250	 * will forward the LFPS to its upstream link.  The exit latency is the
 251	 * delay, plus the PEL that we calculated for this hub.
 252	 */
 253	hub_pel = port_to_port_exit_latency * 1000 + hub_lpm_params->pel;
 254
 255	/*
 256	 * According to figure C-7 in the USB 3.0 spec, the PEL for this device
 257	 * is the greater of the two exit latencies.
 258	 */
 259	if (first_link_pel > hub_pel)
 260		udev_lpm_params->pel = first_link_pel;
 261	else
 262		udev_lpm_params->pel = hub_pel;
 263}
 264
 265/*
 266 * Set the System Exit Latency (SEL) to indicate the total worst-case time from
 267 * when a device initiates a transition to U0, until when it will receive the
 268 * first packet from the host controller.
 269 *
 270 * Section C.1.5.1 describes the four components to this:
 271 *  - t1: device PEL
 272 *  - t2: time for the ERDY to make it from the device to the host.
 273 *  - t3: a host-specific delay to process the ERDY.
 274 *  - t4: time for the packet to make it from the host to the device.
 275 *
 276 * t3 is specific to both the xHCI host and the platform the host is integrated
 277 * into.  The Intel HW folks have said it's negligible, FIXME if a different
 278 * vendor says otherwise.
 279 */
 280static void usb_set_lpm_sel(struct usb_device *udev,
 281		struct usb3_lpm_parameters *udev_lpm_params)
 282{
 283	struct usb_device *parent;
 284	unsigned int num_hubs;
 285	unsigned int total_sel;
 286
 287	/* t1 = device PEL */
 288	total_sel = udev_lpm_params->pel;
 289	/* How many external hubs are in between the device & the root port. */
 290	for (parent = udev->parent, num_hubs = 0; parent->parent;
 291			parent = parent->parent)
 292		num_hubs++;
 293	/* t2 = 2.1us + 250ns * (num_hubs - 1) */
 294	if (num_hubs > 0)
 295		total_sel += 2100 + 250 * (num_hubs - 1);
 296
 297	/* t4 = 250ns * num_hubs */
 298	total_sel += 250 * num_hubs;
 299
 300	udev_lpm_params->sel = total_sel;
 301}
 302
 303static void usb_set_lpm_parameters(struct usb_device *udev)
 304{
 305	struct usb_hub *hub;
 306	unsigned int port_to_port_delay;
 307	unsigned int udev_u1_del;
 308	unsigned int udev_u2_del;
 309	unsigned int hub_u1_del;
 310	unsigned int hub_u2_del;
 311
 312	if (!udev->lpm_capable || udev->speed < USB_SPEED_SUPER)
 313		return;
 314
 315	hub = usb_hub_to_struct_hub(udev->parent);
 316	/* It doesn't take time to transition the roothub into U0, since it
 317	 * doesn't have an upstream link.
 318	 */
 319	if (!hub)
 320		return;
 321
 322	udev_u1_del = udev->bos->ss_cap->bU1devExitLat;
 323	udev_u2_del = le16_to_cpu(udev->bos->ss_cap->bU2DevExitLat);
 324	hub_u1_del = udev->parent->bos->ss_cap->bU1devExitLat;
 325	hub_u2_del = le16_to_cpu(udev->parent->bos->ss_cap->bU2DevExitLat);
 326
 327	usb_set_lpm_mel(udev, &udev->u1_params, udev_u1_del,
 328			hub, &udev->parent->u1_params, hub_u1_del);
 329
 330	usb_set_lpm_mel(udev, &udev->u2_params, udev_u2_del,
 331			hub, &udev->parent->u2_params, hub_u2_del);
 332
 333	/*
 334	 * Appendix C, section C.2.2.2, says that there is a slight delay from
 335	 * when the parent hub notices the downstream port is trying to
 336	 * transition to U0 to when the hub initiates a U0 transition on its
 337	 * upstream port.  The section says the delays are tPort2PortU1EL and
 338	 * tPort2PortU2EL, but it doesn't define what they are.
 339	 *
 340	 * The hub chapter, sections 10.4.2.4 and 10.4.2.5 seem to be talking
 341	 * about the same delays.  Use the maximum delay calculations from those
 342	 * sections.  For U1, it's tHubPort2PortExitLat, which is 1us max.  For
 343	 * U2, it's tHubPort2PortExitLat + U2DevExitLat - U1DevExitLat.  I
 344	 * assume the device exit latencies they are talking about are the hub
 345	 * exit latencies.
 346	 *
 347	 * What do we do if the U2 exit latency is less than the U1 exit
 348	 * latency?  It's possible, although not likely...
 349	 */
 350	port_to_port_delay = 1;
 351
 352	usb_set_lpm_pel(udev, &udev->u1_params, udev_u1_del,
 353			hub, &udev->parent->u1_params, hub_u1_del,
 354			port_to_port_delay);
 355
 356	if (hub_u2_del > hub_u1_del)
 357		port_to_port_delay = 1 + hub_u2_del - hub_u1_del;
 358	else
 359		port_to_port_delay = 1 + hub_u1_del;
 360
 361	usb_set_lpm_pel(udev, &udev->u2_params, udev_u2_del,
 362			hub, &udev->parent->u2_params, hub_u2_del,
 363			port_to_port_delay);
 364
 365	/* Now that we've got PEL, calculate SEL. */
 366	usb_set_lpm_sel(udev, &udev->u1_params);
 367	usb_set_lpm_sel(udev, &udev->u2_params);
 368}
 369
 370/* USB 2.0 spec Section 11.24.4.5 */
 371static int get_hub_descriptor(struct usb_device *hdev,
 372		struct usb_hub_descriptor *desc)
 373{
 374	int i, ret, size;
 375	unsigned dtype;
 376
 377	if (hub_is_superspeed(hdev)) {
 378		dtype = USB_DT_SS_HUB;
 379		size = USB_DT_SS_HUB_SIZE;
 380	} else {
 381		dtype = USB_DT_HUB;
 382		size = sizeof(struct usb_hub_descriptor);
 383	}
 384
 385	for (i = 0; i < 3; i++) {
 386		ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 387			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
 388			dtype << 8, 0, desc, size,
 389			USB_CTRL_GET_TIMEOUT);
 390		if (hub_is_superspeed(hdev)) {
 391			if (ret == size)
 392				return ret;
 393		} else if (ret >= USB_DT_HUB_NONVAR_SIZE + 2) {
 394			/* Make sure we have the DeviceRemovable field. */
 395			size = USB_DT_HUB_NONVAR_SIZE + desc->bNbrPorts / 8 + 1;
 396			if (ret < size)
 397				return -EMSGSIZE;
 398			return ret;
 399		}
 400	}
 401	return -EINVAL;
 402}
 403
 404/*
 405 * USB 2.0 spec Section 11.24.2.1
 406 */
 407static int clear_hub_feature(struct usb_device *hdev, int feature)
 408{
 409	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 410		USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
 411}
 412
 413/*
 414 * USB 2.0 spec Section 11.24.2.2
 415 */
 416int usb_clear_port_feature(struct usb_device *hdev, int port1, int feature)
 417{
 418	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 419		USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
 420		NULL, 0, 1000);
 421}
 422
 423/*
 424 * USB 2.0 spec Section 11.24.2.13
 425 */
 426static int set_port_feature(struct usb_device *hdev, int port1, int feature)
 427{
 428	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 429		USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
 430		NULL, 0, 1000);
 431}
 432
 433static char *to_led_name(int selector)
 434{
 435	switch (selector) {
 436	case HUB_LED_AMBER:
 437		return "amber";
 438	case HUB_LED_GREEN:
 439		return "green";
 440	case HUB_LED_OFF:
 441		return "off";
 442	case HUB_LED_AUTO:
 443		return "auto";
 444	default:
 445		return "??";
 446	}
 447}
 448
 449/*
 450 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
 451 * for info about using port indicators
 452 */
 453static void set_port_led(struct usb_hub *hub, int port1, int selector)
 454{
 455	struct usb_port *port_dev = hub->ports[port1 - 1];
 456	int status;
 457
 458	status = set_port_feature(hub->hdev, (selector << 8) | port1,
 459			USB_PORT_FEAT_INDICATOR);
 460	dev_dbg(&port_dev->dev, "indicator %s status %d\n",
 461		to_led_name(selector), status);
 462}
 463
 464#define	LED_CYCLE_PERIOD	((2*HZ)/3)
 465
 466static void led_work(struct work_struct *work)
 467{
 468	struct usb_hub		*hub =
 469		container_of(work, struct usb_hub, leds.work);
 470	struct usb_device	*hdev = hub->hdev;
 471	unsigned		i;
 472	unsigned		changed = 0;
 473	int			cursor = -1;
 474
 475	if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
 476		return;
 477
 478	for (i = 0; i < hdev->maxchild; i++) {
 479		unsigned	selector, mode;
 480
 481		/* 30%-50% duty cycle */
 482
 483		switch (hub->indicator[i]) {
 484		/* cycle marker */
 485		case INDICATOR_CYCLE:
 486			cursor = i;
 487			selector = HUB_LED_AUTO;
 488			mode = INDICATOR_AUTO;
 489			break;
 490		/* blinking green = sw attention */
 491		case INDICATOR_GREEN_BLINK:
 492			selector = HUB_LED_GREEN;
 493			mode = INDICATOR_GREEN_BLINK_OFF;
 494			break;
 495		case INDICATOR_GREEN_BLINK_OFF:
 496			selector = HUB_LED_OFF;
 497			mode = INDICATOR_GREEN_BLINK;
 498			break;
 499		/* blinking amber = hw attention */
 500		case INDICATOR_AMBER_BLINK:
 501			selector = HUB_LED_AMBER;
 502			mode = INDICATOR_AMBER_BLINK_OFF;
 503			break;
 504		case INDICATOR_AMBER_BLINK_OFF:
 505			selector = HUB_LED_OFF;
 506			mode = INDICATOR_AMBER_BLINK;
 507			break;
 508		/* blink green/amber = reserved */
 509		case INDICATOR_ALT_BLINK:
 510			selector = HUB_LED_GREEN;
 511			mode = INDICATOR_ALT_BLINK_OFF;
 512			break;
 513		case INDICATOR_ALT_BLINK_OFF:
 514			selector = HUB_LED_AMBER;
 515			mode = INDICATOR_ALT_BLINK;
 516			break;
 517		default:
 518			continue;
 519		}
 520		if (selector != HUB_LED_AUTO)
 521			changed = 1;
 522		set_port_led(hub, i + 1, selector);
 523		hub->indicator[i] = mode;
 524	}
 525	if (!changed && blinkenlights) {
 526		cursor++;
 527		cursor %= hdev->maxchild;
 528		set_port_led(hub, cursor + 1, HUB_LED_GREEN);
 529		hub->indicator[cursor] = INDICATOR_CYCLE;
 530		changed++;
 531	}
 532	if (changed)
 533		queue_delayed_work(system_power_efficient_wq,
 534				&hub->leds, LED_CYCLE_PERIOD);
 535}
 536
 537/* use a short timeout for hub/port status fetches */
 538#define	USB_STS_TIMEOUT		1000
 539#define	USB_STS_RETRIES		5
 540
 541/*
 542 * USB 2.0 spec Section 11.24.2.6
 543 */
 544static int get_hub_status(struct usb_device *hdev,
 545		struct usb_hub_status *data)
 546{
 547	int i, status = -ETIMEDOUT;
 548
 549	for (i = 0; i < USB_STS_RETRIES &&
 550			(status == -ETIMEDOUT || status == -EPIPE); i++) {
 551		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 552			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
 553			data, sizeof(*data), USB_STS_TIMEOUT);
 554	}
 555	return status;
 556}
 557
 558/*
 559 * USB 2.0 spec Section 11.24.2.7
 560 * USB 3.1 takes into use the wValue and wLength fields, spec Section 10.16.2.6
 561 */
 562static int get_port_status(struct usb_device *hdev, int port1,
 563			   void *data, u16 value, u16 length)
 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_PORT, value,
 571			port1, data, length, USB_STS_TIMEOUT);
 572	}
 573	return status;
 574}
 575
 576static int hub_ext_port_status(struct usb_hub *hub, int port1, int type,
 577			       u16 *status, u16 *change, u32 *ext_status)
 578{
 579	int ret;
 580	int len = 4;
 581
 582	if (type != HUB_PORT_STATUS)
 583		len = 8;
 584
 585	mutex_lock(&hub->status_mutex);
 586	ret = get_port_status(hub->hdev, port1, &hub->status->port, type, len);
 587	if (ret < len) {
 588		if (ret != -ENODEV)
 589			dev_err(hub->intfdev,
 590				"%s failed (err = %d)\n", __func__, ret);
 591		if (ret >= 0)
 592			ret = -EIO;
 593	} else {
 594		*status = le16_to_cpu(hub->status->port.wPortStatus);
 595		*change = le16_to_cpu(hub->status->port.wPortChange);
 596		if (type != HUB_PORT_STATUS && ext_status)
 597			*ext_status = le32_to_cpu(
 598				hub->status->port.dwExtPortStatus);
 599		ret = 0;
 600	}
 601	mutex_unlock(&hub->status_mutex);
 602	return ret;
 603}
 604
 605static int hub_port_status(struct usb_hub *hub, int port1,
 606		u16 *status, u16 *change)
 607{
 608	return hub_ext_port_status(hub, port1, HUB_PORT_STATUS,
 609				   status, change, NULL);
 610}
 611
 612static void hub_resubmit_irq_urb(struct usb_hub *hub)
 613{
 614	unsigned long flags;
 615	int status;
 616
 617	spin_lock_irqsave(&hub->irq_urb_lock, flags);
 618
 619	if (hub->quiescing) {
 620		spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
 621		return;
 622	}
 623
 624	status = usb_submit_urb(hub->urb, GFP_ATOMIC);
 625	if (status && status != -ENODEV && status != -EPERM &&
 626	    status != -ESHUTDOWN) {
 627		dev_err(hub->intfdev, "resubmit --> %d\n", status);
 628		mod_timer(&hub->irq_urb_retry, jiffies + HZ);
 629	}
 630
 631	spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
 632}
 633
 634static void hub_retry_irq_urb(struct timer_list *t)
 635{
 636	struct usb_hub *hub = from_timer(hub, t, irq_urb_retry);
 637
 638	hub_resubmit_irq_urb(hub);
 639}
 640
 641
 642static void kick_hub_wq(struct usb_hub *hub)
 643{
 644	struct usb_interface *intf;
 645
 646	if (hub->disconnected || work_pending(&hub->events))
 647		return;
 648
 649	/*
 650	 * Suppress autosuspend until the event is proceed.
 651	 *
 652	 * Be careful and make sure that the symmetric operation is
 653	 * always called. We are here only when there is no pending
 654	 * work for this hub. Therefore put the interface either when
 655	 * the new work is called or when it is canceled.
 656	 */
 657	intf = to_usb_interface(hub->intfdev);
 658	usb_autopm_get_interface_no_resume(intf);
 659	kref_get(&hub->kref);
 660
 661	if (queue_work(hub_wq, &hub->events))
 662		return;
 663
 664	/* the work has already been scheduled */
 665	usb_autopm_put_interface_async(intf);
 666	kref_put(&hub->kref, hub_release);
 667}
 668
 669void usb_kick_hub_wq(struct usb_device *hdev)
 670{
 671	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
 672
 673	if (hub)
 674		kick_hub_wq(hub);
 675}
 676
 677/*
 678 * Let the USB core know that a USB 3.0 device has sent a Function Wake Device
 679 * Notification, which indicates it had initiated remote wakeup.
 680 *
 681 * USB 3.0 hubs do not report the port link state change from U3 to U0 when the
 682 * device initiates resume, so the USB core will not receive notice of the
 683 * resume through the normal hub interrupt URB.
 684 */
 685void usb_wakeup_notification(struct usb_device *hdev,
 686		unsigned int portnum)
 687{
 688	struct usb_hub *hub;
 689	struct usb_port *port_dev;
 690
 691	if (!hdev)
 692		return;
 693
 694	hub = usb_hub_to_struct_hub(hdev);
 695	if (hub) {
 696		port_dev = hub->ports[portnum - 1];
 697		if (port_dev && port_dev->child)
 698			pm_wakeup_event(&port_dev->child->dev, 0);
 699
 700		set_bit(portnum, hub->wakeup_bits);
 701		kick_hub_wq(hub);
 702	}
 703}
 704EXPORT_SYMBOL_GPL(usb_wakeup_notification);
 705
 706/* completion function, fires on port status changes and various faults */
 707static void hub_irq(struct urb *urb)
 708{
 709	struct usb_hub *hub = urb->context;
 710	int status = urb->status;
 711	unsigned i;
 712	unsigned long bits;
 713
 714	switch (status) {
 715	case -ENOENT:		/* synchronous unlink */
 716	case -ECONNRESET:	/* async unlink */
 717	case -ESHUTDOWN:	/* hardware going away */
 718		return;
 719
 720	default:		/* presumably an error */
 721		/* Cause a hub reset after 10 consecutive errors */
 722		dev_dbg(hub->intfdev, "transfer --> %d\n", status);
 723		if ((++hub->nerrors < 10) || hub->error)
 724			goto resubmit;
 725		hub->error = status;
 726		/* FALL THROUGH */
 727
 728	/* let hub_wq handle things */
 729	case 0:			/* we got data:  port status changed */
 730		bits = 0;
 731		for (i = 0; i < urb->actual_length; ++i)
 732			bits |= ((unsigned long) ((*hub->buffer)[i]))
 733					<< (i*8);
 734		hub->event_bits[0] = bits;
 735		break;
 736	}
 737
 738	hub->nerrors = 0;
 739
 740	/* Something happened, let hub_wq figure it out */
 741	kick_hub_wq(hub);
 742
 743resubmit:
 744	hub_resubmit_irq_urb(hub);
 
 
 
 
 
 745}
 746
 747/* USB 2.0 spec Section 11.24.2.3 */
 748static inline int
 749hub_clear_tt_buffer(struct usb_device *hdev, u16 devinfo, u16 tt)
 750{
 751	/* Need to clear both directions for control ep */
 752	if (((devinfo >> 11) & USB_ENDPOINT_XFERTYPE_MASK) ==
 753			USB_ENDPOINT_XFER_CONTROL) {
 754		int status = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 755				HUB_CLEAR_TT_BUFFER, USB_RT_PORT,
 756				devinfo ^ 0x8000, tt, NULL, 0, 1000);
 757		if (status)
 758			return status;
 759	}
 760	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 761			       HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
 762			       tt, NULL, 0, 1000);
 763}
 764
 765/*
 766 * enumeration blocks hub_wq for a long time. we use keventd instead, since
 767 * long blocking there is the exception, not the rule.  accordingly, HCDs
 768 * talking to TTs must queue control transfers (not just bulk and iso), so
 769 * both can talk to the same hub concurrently.
 770 */
 771static void hub_tt_work(struct work_struct *work)
 772{
 773	struct usb_hub		*hub =
 774		container_of(work, struct usb_hub, tt.clear_work);
 775	unsigned long		flags;
 776
 777	spin_lock_irqsave(&hub->tt.lock, flags);
 778	while (!list_empty(&hub->tt.clear_list)) {
 779		struct list_head	*next;
 780		struct usb_tt_clear	*clear;
 781		struct usb_device	*hdev = hub->hdev;
 782		const struct hc_driver	*drv;
 783		int			status;
 784
 785		next = hub->tt.clear_list.next;
 786		clear = list_entry(next, struct usb_tt_clear, clear_list);
 787		list_del(&clear->clear_list);
 788
 789		/* drop lock so HCD can concurrently report other TT errors */
 790		spin_unlock_irqrestore(&hub->tt.lock, flags);
 791		status = hub_clear_tt_buffer(hdev, clear->devinfo, clear->tt);
 792		if (status && status != -ENODEV)
 793			dev_err(&hdev->dev,
 794				"clear tt %d (%04x) error %d\n",
 795				clear->tt, clear->devinfo, status);
 796
 797		/* Tell the HCD, even if the operation failed */
 798		drv = clear->hcd->driver;
 799		if (drv->clear_tt_buffer_complete)
 800			(drv->clear_tt_buffer_complete)(clear->hcd, clear->ep);
 801
 802		kfree(clear);
 803		spin_lock_irqsave(&hub->tt.lock, flags);
 804	}
 805	spin_unlock_irqrestore(&hub->tt.lock, flags);
 806}
 807
 808/**
 809 * usb_hub_set_port_power - control hub port's power state
 810 * @hdev: USB device belonging to the usb hub
 811 * @hub: target hub
 812 * @port1: port index
 813 * @set: expected status
 814 *
 815 * call this function to control port's power via setting or
 816 * clearing the port's PORT_POWER feature.
 817 *
 818 * Return: 0 if successful. A negative error code otherwise.
 819 */
 820int usb_hub_set_port_power(struct usb_device *hdev, struct usb_hub *hub,
 821			   int port1, bool set)
 822{
 823	int ret;
 824
 825	if (set)
 826		ret = set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
 827	else
 828		ret = usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
 829
 830	if (ret)
 831		return ret;
 832
 833	if (set)
 834		set_bit(port1, hub->power_bits);
 835	else
 836		clear_bit(port1, hub->power_bits);
 837	return 0;
 838}
 839
 840/**
 841 * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
 842 * @urb: an URB associated with the failed or incomplete split transaction
 843 *
 844 * High speed HCDs use this to tell the hub driver that some split control or
 845 * bulk transaction failed in a way that requires clearing internal state of
 846 * a transaction translator.  This is normally detected (and reported) from
 847 * interrupt context.
 848 *
 849 * It may not be possible for that hub to handle additional full (or low)
 850 * speed transactions until that state is fully cleared out.
 851 *
 852 * Return: 0 if successful. A negative error code otherwise.
 853 */
 854int usb_hub_clear_tt_buffer(struct urb *urb)
 855{
 856	struct usb_device	*udev = urb->dev;
 857	int			pipe = urb->pipe;
 858	struct usb_tt		*tt = udev->tt;
 859	unsigned long		flags;
 860	struct usb_tt_clear	*clear;
 861
 862	/* we've got to cope with an arbitrary number of pending TT clears,
 863	 * since each TT has "at least two" buffers that can need it (and
 864	 * there can be many TTs per hub).  even if they're uncommon.
 865	 */
 866	clear = kmalloc(sizeof *clear, GFP_ATOMIC);
 867	if (clear == NULL) {
 868		dev_err(&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
 869		/* FIXME recover somehow ... RESET_TT? */
 870		return -ENOMEM;
 871	}
 872
 873	/* info that CLEAR_TT_BUFFER needs */
 874	clear->tt = tt->multi ? udev->ttport : 1;
 875	clear->devinfo = usb_pipeendpoint (pipe);
 876	clear->devinfo |= ((u16)udev->devaddr) << 4;
 877	clear->devinfo |= usb_pipecontrol(pipe)
 878			? (USB_ENDPOINT_XFER_CONTROL << 11)
 879			: (USB_ENDPOINT_XFER_BULK << 11);
 880	if (usb_pipein(pipe))
 881		clear->devinfo |= 1 << 15;
 882
 883	/* info for completion callback */
 884	clear->hcd = bus_to_hcd(udev->bus);
 885	clear->ep = urb->ep;
 886
 887	/* tell keventd to clear state for this TT */
 888	spin_lock_irqsave(&tt->lock, flags);
 889	list_add_tail(&clear->clear_list, &tt->clear_list);
 890	schedule_work(&tt->clear_work);
 891	spin_unlock_irqrestore(&tt->lock, flags);
 892	return 0;
 893}
 894EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer);
 895
 896static void hub_power_on(struct usb_hub *hub, bool do_delay)
 897{
 898	int port1;
 899
 900	/* Enable power on each port.  Some hubs have reserved values
 901	 * of LPSM (> 2) in their descriptors, even though they are
 902	 * USB 2.0 hubs.  Some hubs do not implement port-power switching
 903	 * but only emulate it.  In all cases, the ports won't work
 904	 * unless we send these messages to the hub.
 905	 */
 906	if (hub_is_port_power_switchable(hub))
 907		dev_dbg(hub->intfdev, "enabling power on all ports\n");
 908	else
 909		dev_dbg(hub->intfdev, "trying to enable port power on "
 910				"non-switchable hub\n");
 911	for (port1 = 1; port1 <= hub->hdev->maxchild; port1++)
 912		if (test_bit(port1, hub->power_bits))
 913			set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
 914		else
 915			usb_clear_port_feature(hub->hdev, port1,
 916						USB_PORT_FEAT_POWER);
 917	if (do_delay)
 918		msleep(hub_power_on_good_delay(hub));
 919}
 920
 921static int hub_hub_status(struct usb_hub *hub,
 922		u16 *status, u16 *change)
 923{
 924	int ret;
 925
 926	mutex_lock(&hub->status_mutex);
 927	ret = get_hub_status(hub->hdev, &hub->status->hub);
 928	if (ret < 0) {
 929		if (ret != -ENODEV)
 930			dev_err(hub->intfdev,
 931				"%s failed (err = %d)\n", __func__, ret);
 932	} else {
 933		*status = le16_to_cpu(hub->status->hub.wHubStatus);
 934		*change = le16_to_cpu(hub->status->hub.wHubChange);
 935		ret = 0;
 936	}
 937	mutex_unlock(&hub->status_mutex);
 938	return ret;
 939}
 940
 941static int hub_set_port_link_state(struct usb_hub *hub, int port1,
 942			unsigned int link_status)
 943{
 944	return set_port_feature(hub->hdev,
 945			port1 | (link_status << 3),
 946			USB_PORT_FEAT_LINK_STATE);
 947}
 948
 949/*
 950 * Disable a port and mark a logical connect-change event, so that some
 951 * time later hub_wq will disconnect() any existing usb_device on the port
 952 * and will re-enumerate if there actually is a device attached.
 953 */
 954static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
 955{
 956	dev_dbg(&hub->ports[port1 - 1]->dev, "logical disconnect\n");
 957	hub_port_disable(hub, port1, 1);
 958
 959	/* FIXME let caller ask to power down the port:
 960	 *  - some devices won't enumerate without a VBUS power cycle
 961	 *  - SRP saves power that way
 962	 *  - ... new call, TBD ...
 963	 * That's easy if this hub can switch power per-port, and
 964	 * hub_wq reactivates the port later (timer, SRP, etc).
 965	 * Powerdown must be optional, because of reset/DFU.
 966	 */
 967
 968	set_bit(port1, hub->change_bits);
 969	kick_hub_wq(hub);
 970}
 971
 972/**
 973 * usb_remove_device - disable a device's port on its parent hub
 974 * @udev: device to be disabled and removed
 975 * Context: @udev locked, must be able to sleep.
 976 *
 977 * After @udev's port has been disabled, hub_wq is notified and it will
 978 * see that the device has been disconnected.  When the device is
 979 * physically unplugged and something is plugged in, the events will
 980 * be received and processed normally.
 981 *
 982 * Return: 0 if successful. A negative error code otherwise.
 983 */
 984int usb_remove_device(struct usb_device *udev)
 985{
 986	struct usb_hub *hub;
 987	struct usb_interface *intf;
 988
 989	if (!udev->parent)	/* Can't remove a root hub */
 990		return -EINVAL;
 991	hub = usb_hub_to_struct_hub(udev->parent);
 992	intf = to_usb_interface(hub->intfdev);
 993
 994	usb_autopm_get_interface(intf);
 995	set_bit(udev->portnum, hub->removed_bits);
 996	hub_port_logical_disconnect(hub, udev->portnum);
 997	usb_autopm_put_interface(intf);
 998	return 0;
 999}
1000
1001enum hub_activation_type {
1002	HUB_INIT, HUB_INIT2, HUB_INIT3,		/* INITs must come first */
1003	HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
1004};
1005
1006static void hub_init_func2(struct work_struct *ws);
1007static void hub_init_func3(struct work_struct *ws);
1008
1009static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
1010{
1011	struct usb_device *hdev = hub->hdev;
1012	struct usb_hcd *hcd;
1013	int ret;
1014	int port1;
1015	int status;
1016	bool need_debounce_delay = false;
1017	unsigned delay;
1018
1019	/* Continue a partial initialization */
1020	if (type == HUB_INIT2 || type == HUB_INIT3) {
1021		device_lock(&hdev->dev);
1022
1023		/* Was the hub disconnected while we were waiting? */
1024		if (hub->disconnected)
1025			goto disconnected;
1026		if (type == HUB_INIT2)
1027			goto init2;
1028		goto init3;
1029	}
1030	kref_get(&hub->kref);
1031
1032	/* The superspeed hub except for root hub has to use Hub Depth
1033	 * value as an offset into the route string to locate the bits
1034	 * it uses to determine the downstream port number. So hub driver
1035	 * should send a set hub depth request to superspeed hub after
1036	 * the superspeed hub is set configuration in initialization or
1037	 * reset procedure.
1038	 *
1039	 * After a resume, port power should still be on.
1040	 * For any other type of activation, turn it on.
1041	 */
1042	if (type != HUB_RESUME) {
1043		if (hdev->parent && hub_is_superspeed(hdev)) {
1044			ret = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
1045					HUB_SET_DEPTH, USB_RT_HUB,
1046					hdev->level - 1, 0, NULL, 0,
1047					USB_CTRL_SET_TIMEOUT);
1048			if (ret < 0)
1049				dev_err(hub->intfdev,
1050						"set hub depth failed\n");
1051		}
1052
1053		/* Speed up system boot by using a delayed_work for the
1054		 * hub's initial power-up delays.  This is pretty awkward
1055		 * and the implementation looks like a home-brewed sort of
1056		 * setjmp/longjmp, but it saves at least 100 ms for each
1057		 * root hub (assuming usbcore is compiled into the kernel
1058		 * rather than as a module).  It adds up.
1059		 *
1060		 * This can't be done for HUB_RESUME or HUB_RESET_RESUME
1061		 * because for those activation types the ports have to be
1062		 * operational when we return.  In theory this could be done
1063		 * for HUB_POST_RESET, but it's easier not to.
1064		 */
1065		if (type == HUB_INIT) {
1066			delay = hub_power_on_good_delay(hub);
1067
1068			hub_power_on(hub, false);
1069			INIT_DELAYED_WORK(&hub->init_work, hub_init_func2);
1070			queue_delayed_work(system_power_efficient_wq,
1071					&hub->init_work,
1072					msecs_to_jiffies(delay));
1073
1074			/* Suppress autosuspend until init is done */
1075			usb_autopm_get_interface_no_resume(
1076					to_usb_interface(hub->intfdev));
1077			return;		/* Continues at init2: below */
1078		} else if (type == HUB_RESET_RESUME) {
1079			/* The internal host controller state for the hub device
1080			 * may be gone after a host power loss on system resume.
1081			 * Update the device's info so the HW knows it's a hub.
1082			 */
1083			hcd = bus_to_hcd(hdev->bus);
1084			if (hcd->driver->update_hub_device) {
1085				ret = hcd->driver->update_hub_device(hcd, hdev,
1086						&hub->tt, GFP_NOIO);
1087				if (ret < 0) {
1088					dev_err(hub->intfdev,
1089						"Host not accepting hub info update\n");
1090					dev_err(hub->intfdev,
1091						"LS/FS devices and hubs may not work under this hub\n");
1092				}
1093			}
1094			hub_power_on(hub, true);
1095		} else {
1096			hub_power_on(hub, true);
1097		}
1098	}
1099 init2:
1100
1101	/*
1102	 * Check each port and set hub->change_bits to let hub_wq know
1103	 * which ports need attention.
1104	 */
1105	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
1106		struct usb_port *port_dev = hub->ports[port1 - 1];
1107		struct usb_device *udev = port_dev->child;
1108		u16 portstatus, portchange;
1109
1110		portstatus = portchange = 0;
1111		status = hub_port_status(hub, port1, &portstatus, &portchange);
1112		if (status)
1113			goto abort;
1114
1115		if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
1116			dev_dbg(&port_dev->dev, "status %04x change %04x\n",
1117					portstatus, portchange);
1118
1119		/*
1120		 * After anything other than HUB_RESUME (i.e., initialization
1121		 * or any sort of reset), every port should be disabled.
1122		 * Unconnected ports should likewise be disabled (paranoia),
1123		 * and so should ports for which we have no usb_device.
1124		 */
1125		if ((portstatus & USB_PORT_STAT_ENABLE) && (
1126				type != HUB_RESUME ||
1127				!(portstatus & USB_PORT_STAT_CONNECTION) ||
1128				!udev ||
1129				udev->state == USB_STATE_NOTATTACHED)) {
1130			/*
1131			 * USB3 protocol ports will automatically transition
1132			 * to Enabled state when detect an USB3.0 device attach.
1133			 * Do not disable USB3 protocol ports, just pretend
1134			 * power was lost
1135			 */
1136			portstatus &= ~USB_PORT_STAT_ENABLE;
1137			if (!hub_is_superspeed(hdev))
1138				usb_clear_port_feature(hdev, port1,
1139						   USB_PORT_FEAT_ENABLE);
1140		}
1141
1142		/* Make sure a warm-reset request is handled by port_event */
1143		if (type == HUB_RESUME &&
1144		    hub_port_warm_reset_required(hub, port1, portstatus))
1145			set_bit(port1, hub->event_bits);
1146
1147		/*
1148		 * Add debounce if USB3 link is in polling/link training state.
1149		 * Link will automatically transition to Enabled state after
1150		 * link training completes.
1151		 */
1152		if (hub_is_superspeed(hdev) &&
1153		    ((portstatus & USB_PORT_STAT_LINK_STATE) ==
1154						USB_SS_PORT_LS_POLLING))
1155			need_debounce_delay = true;
1156
1157		/* Clear status-change flags; we'll debounce later */
1158		if (portchange & USB_PORT_STAT_C_CONNECTION) {
1159			need_debounce_delay = true;
1160			usb_clear_port_feature(hub->hdev, port1,
1161					USB_PORT_FEAT_C_CONNECTION);
1162		}
1163		if (portchange & USB_PORT_STAT_C_ENABLE) {
1164			need_debounce_delay = true;
1165			usb_clear_port_feature(hub->hdev, port1,
1166					USB_PORT_FEAT_C_ENABLE);
1167		}
1168		if (portchange & USB_PORT_STAT_C_RESET) {
1169			need_debounce_delay = true;
1170			usb_clear_port_feature(hub->hdev, port1,
1171					USB_PORT_FEAT_C_RESET);
1172		}
1173		if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
1174				hub_is_superspeed(hub->hdev)) {
1175			need_debounce_delay = true;
1176			usb_clear_port_feature(hub->hdev, port1,
1177					USB_PORT_FEAT_C_BH_PORT_RESET);
1178		}
1179		/* We can forget about a "removed" device when there's a
1180		 * physical disconnect or the connect status changes.
1181		 */
1182		if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
1183				(portchange & USB_PORT_STAT_C_CONNECTION))
1184			clear_bit(port1, hub->removed_bits);
1185
1186		if (!udev || udev->state == USB_STATE_NOTATTACHED) {
1187			/* Tell hub_wq to disconnect the device or
1188			 * check for a new connection or over current condition.
1189			 * Based on USB2.0 Spec Section 11.12.5,
1190			 * C_PORT_OVER_CURRENT could be set while
1191			 * PORT_OVER_CURRENT is not. So check for any of them.
1192			 */
1193			if (udev || (portstatus & USB_PORT_STAT_CONNECTION) ||
1194			    (portstatus & USB_PORT_STAT_OVERCURRENT) ||
1195			    (portchange & USB_PORT_STAT_C_OVERCURRENT))
1196				set_bit(port1, hub->change_bits);
1197
1198		} else if (portstatus & USB_PORT_STAT_ENABLE) {
1199			bool port_resumed = (portstatus &
1200					USB_PORT_STAT_LINK_STATE) ==
1201				USB_SS_PORT_LS_U0;
1202			/* The power session apparently survived the resume.
1203			 * If there was an overcurrent or suspend change
1204			 * (i.e., remote wakeup request), have hub_wq
1205			 * take care of it.  Look at the port link state
1206			 * for USB 3.0 hubs, since they don't have a suspend
1207			 * change bit, and they don't set the port link change
1208			 * bit on device-initiated resume.
1209			 */
1210			if (portchange || (hub_is_superspeed(hub->hdev) &&
1211						port_resumed))
1212				set_bit(port1, hub->change_bits);
1213
1214		} else if (udev->persist_enabled) {
1215#ifdef CONFIG_PM
1216			udev->reset_resume = 1;
1217#endif
1218			/* Don't set the change_bits when the device
1219			 * was powered off.
1220			 */
1221			if (test_bit(port1, hub->power_bits))
1222				set_bit(port1, hub->change_bits);
1223
1224		} else {
1225			/* The power session is gone; tell hub_wq */
1226			usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1227			set_bit(port1, hub->change_bits);
1228		}
1229	}
1230
1231	/* If no port-status-change flags were set, we don't need any
1232	 * debouncing.  If flags were set we can try to debounce the
1233	 * ports all at once right now, instead of letting hub_wq do them
1234	 * one at a time later on.
1235	 *
1236	 * If any port-status changes do occur during this delay, hub_wq
1237	 * will see them later and handle them normally.
1238	 */
1239	if (need_debounce_delay) {
1240		delay = HUB_DEBOUNCE_STABLE;
1241
1242		/* Don't do a long sleep inside a workqueue routine */
1243		if (type == HUB_INIT2) {
1244			INIT_DELAYED_WORK(&hub->init_work, hub_init_func3);
1245			queue_delayed_work(system_power_efficient_wq,
1246					&hub->init_work,
1247					msecs_to_jiffies(delay));
1248			device_unlock(&hdev->dev);
1249			return;		/* Continues at init3: below */
1250		} else {
1251			msleep(delay);
1252		}
1253	}
1254 init3:
1255	hub->quiescing = 0;
1256
1257	status = usb_submit_urb(hub->urb, GFP_NOIO);
1258	if (status < 0)
1259		dev_err(hub->intfdev, "activate --> %d\n", status);
1260	if (hub->has_indicators && blinkenlights)
1261		queue_delayed_work(system_power_efficient_wq,
1262				&hub->leds, LED_CYCLE_PERIOD);
1263
1264	/* Scan all ports that need attention */
1265	kick_hub_wq(hub);
1266 abort:
1267	if (type == HUB_INIT2 || type == HUB_INIT3) {
1268		/* Allow autosuspend if it was suppressed */
1269 disconnected:
1270		usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
1271		device_unlock(&hdev->dev);
1272	}
1273
1274	kref_put(&hub->kref, hub_release);
1275}
1276
1277/* Implement the continuations for the delays above */
1278static void hub_init_func2(struct work_struct *ws)
1279{
1280	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1281
1282	hub_activate(hub, HUB_INIT2);
1283}
1284
1285static void hub_init_func3(struct work_struct *ws)
1286{
1287	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1288
1289	hub_activate(hub, HUB_INIT3);
1290}
1291
1292enum hub_quiescing_type {
1293	HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
1294};
1295
1296static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
1297{
1298	struct usb_device *hdev = hub->hdev;
1299	unsigned long flags;
1300	int i;
1301
1302	/* hub_wq and related activity won't re-trigger */
1303	spin_lock_irqsave(&hub->irq_urb_lock, flags);
1304	hub->quiescing = 1;
1305	spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
1306
1307	if (type != HUB_SUSPEND) {
1308		/* Disconnect all the children */
1309		for (i = 0; i < hdev->maxchild; ++i) {
1310			if (hub->ports[i]->child)
1311				usb_disconnect(&hub->ports[i]->child);
1312		}
1313	}
1314
1315	/* Stop hub_wq and related activity */
1316	del_timer_sync(&hub->irq_urb_retry);
1317	usb_kill_urb(hub->urb);
1318	if (hub->has_indicators)
1319		cancel_delayed_work_sync(&hub->leds);
1320	if (hub->tt.hub)
1321		flush_work(&hub->tt.clear_work);
1322}
1323
1324static void hub_pm_barrier_for_all_ports(struct usb_hub *hub)
1325{
1326	int i;
1327
1328	for (i = 0; i < hub->hdev->maxchild; ++i)
1329		pm_runtime_barrier(&hub->ports[i]->dev);
1330}
1331
1332/* caller has locked the hub device */
1333static int hub_pre_reset(struct usb_interface *intf)
1334{
1335	struct usb_hub *hub = usb_get_intfdata(intf);
1336
1337	hub_quiesce(hub, HUB_PRE_RESET);
1338	hub->in_reset = 1;
1339	hub_pm_barrier_for_all_ports(hub);
1340	return 0;
1341}
1342
1343/* caller has locked the hub device */
1344static int hub_post_reset(struct usb_interface *intf)
1345{
1346	struct usb_hub *hub = usb_get_intfdata(intf);
1347
1348	hub->in_reset = 0;
1349	hub_pm_barrier_for_all_ports(hub);
1350	hub_activate(hub, HUB_POST_RESET);
1351	return 0;
1352}
1353
1354static int hub_configure(struct usb_hub *hub,
1355	struct usb_endpoint_descriptor *endpoint)
1356{
1357	struct usb_hcd *hcd;
1358	struct usb_device *hdev = hub->hdev;
1359	struct device *hub_dev = hub->intfdev;
1360	u16 hubstatus, hubchange;
1361	u16 wHubCharacteristics;
1362	unsigned int pipe;
1363	int maxp, ret, i;
1364	char *message = "out of memory";
1365	unsigned unit_load;
1366	unsigned full_load;
1367	unsigned maxchild;
1368
1369	hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
1370	if (!hub->buffer) {
1371		ret = -ENOMEM;
1372		goto fail;
1373	}
1374
1375	hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
1376	if (!hub->status) {
1377		ret = -ENOMEM;
1378		goto fail;
1379	}
1380	mutex_init(&hub->status_mutex);
1381
1382	hub->descriptor = kzalloc(sizeof(*hub->descriptor), GFP_KERNEL);
1383	if (!hub->descriptor) {
1384		ret = -ENOMEM;
1385		goto fail;
1386	}
1387
1388	/* Request the entire hub descriptor.
1389	 * hub->descriptor can handle USB_MAXCHILDREN ports,
1390	 * but a (non-SS) hub can/will return fewer bytes here.
1391	 */
1392	ret = get_hub_descriptor(hdev, hub->descriptor);
1393	if (ret < 0) {
1394		message = "can't read hub descriptor";
1395		goto fail;
1396	}
1397
1398	maxchild = USB_MAXCHILDREN;
1399	if (hub_is_superspeed(hdev))
1400		maxchild = min_t(unsigned, maxchild, USB_SS_MAXPORTS);
1401
1402	if (hub->descriptor->bNbrPorts > maxchild) {
1403		message = "hub has too many ports!";
1404		ret = -ENODEV;
1405		goto fail;
1406	} else if (hub->descriptor->bNbrPorts == 0) {
1407		message = "hub doesn't have any ports!";
1408		ret = -ENODEV;
1409		goto fail;
1410	}
1411
1412	/*
1413	 * Accumulate wHubDelay + 40ns for every hub in the tree of devices.
1414	 * The resulting value will be used for SetIsochDelay() request.
1415	 */
1416	if (hub_is_superspeed(hdev) || hub_is_superspeedplus(hdev)) {
1417		u32 delay = __le16_to_cpu(hub->descriptor->u.ss.wHubDelay);
1418
1419		if (hdev->parent)
1420			delay += hdev->parent->hub_delay;
1421
1422		delay += USB_TP_TRANSMISSION_DELAY;
1423		hdev->hub_delay = min_t(u32, delay, USB_TP_TRANSMISSION_DELAY_MAX);
1424	}
1425
1426	maxchild = hub->descriptor->bNbrPorts;
1427	dev_info(hub_dev, "%d port%s detected\n", maxchild,
1428			(maxchild == 1) ? "" : "s");
1429
1430	hub->ports = kcalloc(maxchild, sizeof(struct usb_port *), GFP_KERNEL);
1431	if (!hub->ports) {
1432		ret = -ENOMEM;
1433		goto fail;
1434	}
1435
1436	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
1437	if (hub_is_superspeed(hdev)) {
1438		unit_load = 150;
1439		full_load = 900;
1440	} else {
1441		unit_load = 100;
1442		full_load = 500;
1443	}
1444
1445	/* FIXME for USB 3.0, skip for now */
1446	if ((wHubCharacteristics & HUB_CHAR_COMPOUND) &&
1447			!(hub_is_superspeed(hdev))) {
1448		char	portstr[USB_MAXCHILDREN + 1];
1449
1450		for (i = 0; i < maxchild; i++)
1451			portstr[i] = hub->descriptor->u.hs.DeviceRemovable
1452				    [((i + 1) / 8)] & (1 << ((i + 1) % 8))
1453				? 'F' : 'R';
1454		portstr[maxchild] = 0;
1455		dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
1456	} else
1457		dev_dbg(hub_dev, "standalone hub\n");
1458
1459	switch (wHubCharacteristics & HUB_CHAR_LPSM) {
1460	case HUB_CHAR_COMMON_LPSM:
1461		dev_dbg(hub_dev, "ganged power switching\n");
1462		break;
1463	case HUB_CHAR_INDV_PORT_LPSM:
1464		dev_dbg(hub_dev, "individual port power switching\n");
1465		break;
1466	case HUB_CHAR_NO_LPSM:
1467	case HUB_CHAR_LPSM:
1468		dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
1469		break;
1470	}
1471
1472	switch (wHubCharacteristics & HUB_CHAR_OCPM) {
1473	case HUB_CHAR_COMMON_OCPM:
1474		dev_dbg(hub_dev, "global over-current protection\n");
1475		break;
1476	case HUB_CHAR_INDV_PORT_OCPM:
1477		dev_dbg(hub_dev, "individual port over-current protection\n");
1478		break;
1479	case HUB_CHAR_NO_OCPM:
1480	case HUB_CHAR_OCPM:
1481		dev_dbg(hub_dev, "no over-current protection\n");
1482		break;
1483	}
1484
1485	spin_lock_init(&hub->tt.lock);
1486	INIT_LIST_HEAD(&hub->tt.clear_list);
1487	INIT_WORK(&hub->tt.clear_work, hub_tt_work);
1488	switch (hdev->descriptor.bDeviceProtocol) {
1489	case USB_HUB_PR_FS:
1490		break;
1491	case USB_HUB_PR_HS_SINGLE_TT:
1492		dev_dbg(hub_dev, "Single TT\n");
1493		hub->tt.hub = hdev;
1494		break;
1495	case USB_HUB_PR_HS_MULTI_TT:
1496		ret = usb_set_interface(hdev, 0, 1);
1497		if (ret == 0) {
1498			dev_dbg(hub_dev, "TT per port\n");
1499			hub->tt.multi = 1;
1500		} else
1501			dev_err(hub_dev, "Using single TT (err %d)\n",
1502				ret);
1503		hub->tt.hub = hdev;
1504		break;
1505	case USB_HUB_PR_SS:
1506		/* USB 3.0 hubs don't have a TT */
1507		break;
1508	default:
1509		dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
1510			hdev->descriptor.bDeviceProtocol);
1511		break;
1512	}
1513
1514	/* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
1515	switch (wHubCharacteristics & HUB_CHAR_TTTT) {
1516	case HUB_TTTT_8_BITS:
1517		if (hdev->descriptor.bDeviceProtocol != 0) {
1518			hub->tt.think_time = 666;
1519			dev_dbg(hub_dev, "TT requires at most %d "
1520					"FS bit times (%d ns)\n",
1521				8, hub->tt.think_time);
1522		}
1523		break;
1524	case HUB_TTTT_16_BITS:
1525		hub->tt.think_time = 666 * 2;
1526		dev_dbg(hub_dev, "TT requires at most %d "
1527				"FS bit times (%d ns)\n",
1528			16, hub->tt.think_time);
1529		break;
1530	case HUB_TTTT_24_BITS:
1531		hub->tt.think_time = 666 * 3;
1532		dev_dbg(hub_dev, "TT requires at most %d "
1533				"FS bit times (%d ns)\n",
1534			24, hub->tt.think_time);
1535		break;
1536	case HUB_TTTT_32_BITS:
1537		hub->tt.think_time = 666 * 4;
1538		dev_dbg(hub_dev, "TT requires at most %d "
1539				"FS bit times (%d ns)\n",
1540			32, hub->tt.think_time);
1541		break;
1542	}
1543
1544	/* probe() zeroes hub->indicator[] */
1545	if (wHubCharacteristics & HUB_CHAR_PORTIND) {
1546		hub->has_indicators = 1;
1547		dev_dbg(hub_dev, "Port indicators are supported\n");
1548	}
1549
1550	dev_dbg(hub_dev, "power on to power good time: %dms\n",
1551		hub->descriptor->bPwrOn2PwrGood * 2);
1552
1553	/* power budgeting mostly matters with bus-powered hubs,
1554	 * and battery-powered root hubs (may provide just 8 mA).
1555	 */
1556	ret = usb_get_std_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
1557	if (ret) {
1558		message = "can't get hub status";
1559		goto fail;
1560	}
1561	hcd = bus_to_hcd(hdev->bus);
1562	if (hdev == hdev->bus->root_hub) {
1563		if (hcd->power_budget > 0)
1564			hdev->bus_mA = hcd->power_budget;
1565		else
1566			hdev->bus_mA = full_load * maxchild;
1567		if (hdev->bus_mA >= full_load)
1568			hub->mA_per_port = full_load;
1569		else {
1570			hub->mA_per_port = hdev->bus_mA;
1571			hub->limited_power = 1;
1572		}
1573	} else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1574		int remaining = hdev->bus_mA -
1575			hub->descriptor->bHubContrCurrent;
1576
1577		dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
1578			hub->descriptor->bHubContrCurrent);
1579		hub->limited_power = 1;
1580
1581		if (remaining < maxchild * unit_load)
1582			dev_warn(hub_dev,
1583					"insufficient power available "
1584					"to use all downstream ports\n");
1585		hub->mA_per_port = unit_load;	/* 7.2.1 */
1586
1587	} else {	/* Self-powered external hub */
1588		/* FIXME: What about battery-powered external hubs that
1589		 * provide less current per port? */
1590		hub->mA_per_port = full_load;
1591	}
1592	if (hub->mA_per_port < full_load)
1593		dev_dbg(hub_dev, "%umA bus power budget for each child\n",
1594				hub->mA_per_port);
1595
1596	ret = hub_hub_status(hub, &hubstatus, &hubchange);
1597	if (ret < 0) {
1598		message = "can't get hub status";
1599		goto fail;
1600	}
1601
1602	/* local power status reports aren't always correct */
1603	if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
1604		dev_dbg(hub_dev, "local power source is %s\n",
1605			(hubstatus & HUB_STATUS_LOCAL_POWER)
1606			? "lost (inactive)" : "good");
1607
1608	if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
1609		dev_dbg(hub_dev, "%sover-current condition exists\n",
1610			(hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
1611
1612	/* set up the interrupt endpoint
1613	 * We use the EP's maxpacket size instead of (PORTS+1+7)/8
1614	 * bytes as USB2.0[11.12.3] says because some hubs are known
1615	 * to send more data (and thus cause overflow). For root hubs,
1616	 * maxpktsize is defined in hcd.c's fake endpoint descriptors
1617	 * to be big enough for at least USB_MAXCHILDREN ports. */
1618	pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
1619	maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
1620
1621	if (maxp > sizeof(*hub->buffer))
1622		maxp = sizeof(*hub->buffer);
1623
1624	hub->urb = usb_alloc_urb(0, GFP_KERNEL);
1625	if (!hub->urb) {
1626		ret = -ENOMEM;
1627		goto fail;
1628	}
1629
1630	usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1631		hub, endpoint->bInterval);
1632
1633	/* maybe cycle the hub leds */
1634	if (hub->has_indicators && blinkenlights)
1635		hub->indicator[0] = INDICATOR_CYCLE;
1636
1637	mutex_lock(&usb_port_peer_mutex);
1638	for (i = 0; i < maxchild; i++) {
1639		ret = usb_hub_create_port_device(hub, i + 1);
1640		if (ret < 0) {
1641			dev_err(hub->intfdev,
1642				"couldn't create port%d device.\n", i + 1);
1643			break;
1644		}
1645	}
1646	hdev->maxchild = i;
1647	for (i = 0; i < hdev->maxchild; i++) {
1648		struct usb_port *port_dev = hub->ports[i];
1649
1650		pm_runtime_put(&port_dev->dev);
1651	}
1652
1653	mutex_unlock(&usb_port_peer_mutex);
1654	if (ret < 0)
1655		goto fail;
1656
1657	/* Update the HCD's internal representation of this hub before hub_wq
1658	 * starts getting port status changes for devices under the hub.
1659	 */
1660	if (hcd->driver->update_hub_device) {
1661		ret = hcd->driver->update_hub_device(hcd, hdev,
1662				&hub->tt, GFP_KERNEL);
1663		if (ret < 0) {
1664			message = "can't update HCD hub info";
1665			goto fail;
1666		}
1667	}
1668
1669	usb_hub_adjust_deviceremovable(hdev, hub->descriptor);
1670
1671	hub_activate(hub, HUB_INIT);
1672	return 0;
1673
1674fail:
1675	dev_err(hub_dev, "config failed, %s (err %d)\n",
1676			message, ret);
1677	/* hub_disconnect() frees urb and descriptor */
1678	return ret;
1679}
1680
1681static void hub_release(struct kref *kref)
1682{
1683	struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1684
1685	usb_put_dev(hub->hdev);
1686	usb_put_intf(to_usb_interface(hub->intfdev));
1687	kfree(hub);
1688}
1689
1690static unsigned highspeed_hubs;
1691
1692static void hub_disconnect(struct usb_interface *intf)
1693{
1694	struct usb_hub *hub = usb_get_intfdata(intf);
1695	struct usb_device *hdev = interface_to_usbdev(intf);
1696	int port1;
1697
1698	/*
1699	 * Stop adding new hub events. We do not want to block here and thus
1700	 * will not try to remove any pending work item.
1701	 */
1702	hub->disconnected = 1;
1703
1704	/* Disconnect all children and quiesce the hub */
1705	hub->error = 0;
1706	hub_quiesce(hub, HUB_DISCONNECT);
1707
1708	mutex_lock(&usb_port_peer_mutex);
1709
1710	/* Avoid races with recursively_mark_NOTATTACHED() */
1711	spin_lock_irq(&device_state_lock);
1712	port1 = hdev->maxchild;
1713	hdev->maxchild = 0;
1714	usb_set_intfdata(intf, NULL);
1715	spin_unlock_irq(&device_state_lock);
1716
1717	for (; port1 > 0; --port1)
1718		usb_hub_remove_port_device(hub, port1);
1719
1720	mutex_unlock(&usb_port_peer_mutex);
1721
1722	if (hub->hdev->speed == USB_SPEED_HIGH)
1723		highspeed_hubs--;
1724
1725	usb_free_urb(hub->urb);
1726	kfree(hub->ports);
1727	kfree(hub->descriptor);
1728	kfree(hub->status);
1729	kfree(hub->buffer);
1730
1731	pm_suspend_ignore_children(&intf->dev, false);
1732	kref_put(&hub->kref, hub_release);
1733}
1734
1735static bool hub_descriptor_is_sane(struct usb_host_interface *desc)
1736{
1737	/* Some hubs have a subclass of 1, which AFAICT according to the */
1738	/*  specs is not defined, but it works */
1739	if (desc->desc.bInterfaceSubClass != 0 &&
1740	    desc->desc.bInterfaceSubClass != 1)
1741		return false;
1742
1743	/* Multiple endpoints? What kind of mutant ninja-hub is this? */
1744	if (desc->desc.bNumEndpoints != 1)
1745		return false;
1746
1747	/* If the first endpoint is not interrupt IN, we'd better punt! */
1748	if (!usb_endpoint_is_int_in(&desc->endpoint[0].desc))
1749		return false;
1750
1751        return true;
1752}
1753
1754static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1755{
1756	struct usb_host_interface *desc;
1757	struct usb_device *hdev;
1758	struct usb_hub *hub;
1759
1760	desc = intf->cur_altsetting;
1761	hdev = interface_to_usbdev(intf);
1762
1763	/*
1764	 * Set default autosuspend delay as 0 to speedup bus suspend,
1765	 * based on the below considerations:
1766	 *
1767	 * - Unlike other drivers, the hub driver does not rely on the
1768	 *   autosuspend delay to provide enough time to handle a wakeup
1769	 *   event, and the submitted status URB is just to check future
1770	 *   change on hub downstream ports, so it is safe to do it.
1771	 *
1772	 * - The patch might cause one or more auto supend/resume for
1773	 *   below very rare devices when they are plugged into hub
1774	 *   first time:
1775	 *
1776	 *   	devices having trouble initializing, and disconnect
1777	 *   	themselves from the bus and then reconnect a second
1778	 *   	or so later
1779	 *
1780	 *   	devices just for downloading firmware, and disconnects
1781	 *   	themselves after completing it
1782	 *
1783	 *   For these quite rare devices, their drivers may change the
1784	 *   autosuspend delay of their parent hub in the probe() to one
1785	 *   appropriate value to avoid the subtle problem if someone
1786	 *   does care it.
1787	 *
1788	 * - The patch may cause one or more auto suspend/resume on
1789	 *   hub during running 'lsusb', but it is probably too
1790	 *   infrequent to worry about.
1791	 *
1792	 * - Change autosuspend delay of hub can avoid unnecessary auto
1793	 *   suspend timer for hub, also may decrease power consumption
1794	 *   of USB bus.
1795	 *
1796	 * - If user has indicated to prevent autosuspend by passing
1797	 *   usbcore.autosuspend = -1 then keep autosuspend disabled.
1798	 */
1799#ifdef CONFIG_PM
1800	if (hdev->dev.power.autosuspend_delay >= 0)
1801		pm_runtime_set_autosuspend_delay(&hdev->dev, 0);
1802#endif
1803
1804	/*
1805	 * Hubs have proper suspend/resume support, except for root hubs
1806	 * where the controller driver doesn't have bus_suspend and
1807	 * bus_resume methods.
1808	 */
1809	if (hdev->parent) {		/* normal device */
1810		usb_enable_autosuspend(hdev);
1811	} else {			/* root hub */
1812		const struct hc_driver *drv = bus_to_hcd(hdev->bus)->driver;
1813
1814		if (drv->bus_suspend && drv->bus_resume)
1815			usb_enable_autosuspend(hdev);
1816	}
1817
1818	if (hdev->level == MAX_TOPO_LEVEL) {
1819		dev_err(&intf->dev,
1820			"Unsupported bus topology: hub nested too deep\n");
1821		return -E2BIG;
1822	}
1823
1824#ifdef	CONFIG_USB_OTG_BLACKLIST_HUB
1825	if (hdev->parent) {
1826		dev_warn(&intf->dev, "ignoring external hub\n");
1827		return -ENODEV;
1828	}
1829#endif
1830
1831	if (!hub_descriptor_is_sane(desc)) {
1832		dev_err(&intf->dev, "bad descriptor, ignoring hub\n");
1833		return -EIO;
1834	}
1835
1836	/* We found a hub */
1837	dev_info(&intf->dev, "USB hub found\n");
1838
1839	hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1840	if (!hub)
1841		return -ENOMEM;
1842
1843	kref_init(&hub->kref);
1844	hub->intfdev = &intf->dev;
1845	hub->hdev = hdev;
1846	INIT_DELAYED_WORK(&hub->leds, led_work);
1847	INIT_DELAYED_WORK(&hub->init_work, NULL);
1848	INIT_WORK(&hub->events, hub_event);
1849	spin_lock_init(&hub->irq_urb_lock);
1850	timer_setup(&hub->irq_urb_retry, hub_retry_irq_urb, 0);
1851	usb_get_intf(intf);
1852	usb_get_dev(hdev);
1853
1854	usb_set_intfdata(intf, hub);
1855	intf->needs_remote_wakeup = 1;
1856	pm_suspend_ignore_children(&intf->dev, true);
1857
1858	if (hdev->speed == USB_SPEED_HIGH)
1859		highspeed_hubs++;
1860
1861	if (id->driver_info & HUB_QUIRK_CHECK_PORT_AUTOSUSPEND)
1862		hub->quirk_check_port_auto_suspend = 1;
1863
1864	if (hub_configure(hub, &desc->endpoint[0].desc) >= 0)
1865		return 0;
1866
1867	hub_disconnect(intf);
1868	return -ENODEV;
1869}
1870
1871static int
1872hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1873{
1874	struct usb_device *hdev = interface_to_usbdev(intf);
1875	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
1876
1877	/* assert ifno == 0 (part of hub spec) */
1878	switch (code) {
1879	case USBDEVFS_HUB_PORTINFO: {
1880		struct usbdevfs_hub_portinfo *info = user_data;
1881		int i;
1882
1883		spin_lock_irq(&device_state_lock);
1884		if (hdev->devnum <= 0)
1885			info->nports = 0;
1886		else {
1887			info->nports = hdev->maxchild;
1888			for (i = 0; i < info->nports; i++) {
1889				if (hub->ports[i]->child == NULL)
1890					info->port[i] = 0;
1891				else
1892					info->port[i] =
1893						hub->ports[i]->child->devnum;
1894			}
1895		}
1896		spin_unlock_irq(&device_state_lock);
1897
1898		return info->nports + 1;
1899		}
1900
1901	default:
1902		return -ENOSYS;
1903	}
1904}
1905
1906/*
1907 * Allow user programs to claim ports on a hub.  When a device is attached
1908 * to one of these "claimed" ports, the program will "own" the device.
1909 */
1910static int find_port_owner(struct usb_device *hdev, unsigned port1,
1911		struct usb_dev_state ***ppowner)
1912{
1913	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
1914
1915	if (hdev->state == USB_STATE_NOTATTACHED)
1916		return -ENODEV;
1917	if (port1 == 0 || port1 > hdev->maxchild)
1918		return -EINVAL;
1919
1920	/* Devices not managed by the hub driver
1921	 * will always have maxchild equal to 0.
1922	 */
1923	*ppowner = &(hub->ports[port1 - 1]->port_owner);
1924	return 0;
1925}
1926
1927/* In the following three functions, the caller must hold hdev's lock */
1928int usb_hub_claim_port(struct usb_device *hdev, unsigned port1,
1929		       struct usb_dev_state *owner)
1930{
1931	int rc;
1932	struct usb_dev_state **powner;
1933
1934	rc = find_port_owner(hdev, port1, &powner);
1935	if (rc)
1936		return rc;
1937	if (*powner)
1938		return -EBUSY;
1939	*powner = owner;
1940	return rc;
1941}
1942EXPORT_SYMBOL_GPL(usb_hub_claim_port);
1943
1944int usb_hub_release_port(struct usb_device *hdev, unsigned port1,
1945			 struct usb_dev_state *owner)
1946{
1947	int rc;
1948	struct usb_dev_state **powner;
1949
1950	rc = find_port_owner(hdev, port1, &powner);
1951	if (rc)
1952		return rc;
1953	if (*powner != owner)
1954		return -ENOENT;
1955	*powner = NULL;
1956	return rc;
1957}
1958EXPORT_SYMBOL_GPL(usb_hub_release_port);
1959
1960void usb_hub_release_all_ports(struct usb_device *hdev, struct usb_dev_state *owner)
1961{
1962	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
1963	int n;
1964
1965	for (n = 0; n < hdev->maxchild; n++) {
1966		if (hub->ports[n]->port_owner == owner)
1967			hub->ports[n]->port_owner = NULL;
1968	}
1969
1970}
1971
1972/* The caller must hold udev's lock */
1973bool usb_device_is_owned(struct usb_device *udev)
1974{
1975	struct usb_hub *hub;
1976
1977	if (udev->state == USB_STATE_NOTATTACHED || !udev->parent)
1978		return false;
1979	hub = usb_hub_to_struct_hub(udev->parent);
1980	return !!hub->ports[udev->portnum - 1]->port_owner;
1981}
1982
1983static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1984{
1985	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
1986	int i;
1987
1988	for (i = 0; i < udev->maxchild; ++i) {
1989		if (hub->ports[i]->child)
1990			recursively_mark_NOTATTACHED(hub->ports[i]->child);
1991	}
1992	if (udev->state == USB_STATE_SUSPENDED)
1993		udev->active_duration -= jiffies;
1994	udev->state = USB_STATE_NOTATTACHED;
1995}
1996
1997/**
1998 * usb_set_device_state - change a device's current state (usbcore, hcds)
1999 * @udev: pointer to device whose state should be changed
2000 * @new_state: new state value to be stored
2001 *
2002 * udev->state is _not_ fully protected by the device lock.  Although
2003 * most transitions are made only while holding the lock, the state can
2004 * can change to USB_STATE_NOTATTACHED at almost any time.  This
2005 * is so that devices can be marked as disconnected as soon as possible,
2006 * without having to wait for any semaphores to be released.  As a result,
2007 * all changes to any device's state must be protected by the
2008 * device_state_lock spinlock.
2009 *
2010 * Once a device has been added to the device tree, all changes to its state
2011 * should be made using this routine.  The state should _not_ be set directly.
2012 *
2013 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
2014 * Otherwise udev->state is set to new_state, and if new_state is
2015 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
2016 * to USB_STATE_NOTATTACHED.
2017 */
2018void usb_set_device_state(struct usb_device *udev,
2019		enum usb_device_state new_state)
2020{
2021	unsigned long flags;
2022	int wakeup = -1;
2023
2024	spin_lock_irqsave(&device_state_lock, flags);
2025	if (udev->state == USB_STATE_NOTATTACHED)
2026		;	/* do nothing */
2027	else if (new_state != USB_STATE_NOTATTACHED) {
2028
2029		/* root hub wakeup capabilities are managed out-of-band
2030		 * and may involve silicon errata ... ignore them here.
2031		 */
2032		if (udev->parent) {
2033			if (udev->state == USB_STATE_SUSPENDED
2034					|| new_state == USB_STATE_SUSPENDED)
2035				;	/* No change to wakeup settings */
2036			else if (new_state == USB_STATE_CONFIGURED)
2037				wakeup = (udev->quirks &
2038					USB_QUIRK_IGNORE_REMOTE_WAKEUP) ? 0 :
2039					udev->actconfig->desc.bmAttributes &
2040					USB_CONFIG_ATT_WAKEUP;
2041			else
2042				wakeup = 0;
2043		}
2044		if (udev->state == USB_STATE_SUSPENDED &&
2045			new_state != USB_STATE_SUSPENDED)
2046			udev->active_duration -= jiffies;
2047		else if (new_state == USB_STATE_SUSPENDED &&
2048				udev->state != USB_STATE_SUSPENDED)
2049			udev->active_duration += jiffies;
2050		udev->state = new_state;
2051	} else
2052		recursively_mark_NOTATTACHED(udev);
2053	spin_unlock_irqrestore(&device_state_lock, flags);
2054	if (wakeup >= 0)
2055		device_set_wakeup_capable(&udev->dev, wakeup);
2056}
2057EXPORT_SYMBOL_GPL(usb_set_device_state);
2058
2059/*
2060 * Choose a device number.
2061 *
2062 * Device numbers are used as filenames in usbfs.  On USB-1.1 and
2063 * USB-2.0 buses they are also used as device addresses, however on
2064 * USB-3.0 buses the address is assigned by the controller hardware
2065 * and it usually is not the same as the device number.
2066 *
2067 * WUSB devices are simple: they have no hubs behind, so the mapping
2068 * device <-> virtual port number becomes 1:1. Why? to simplify the
2069 * life of the device connection logic in
2070 * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
2071 * handshake we need to assign a temporary address in the unauthorized
2072 * space. For simplicity we use the first virtual port number found to
2073 * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
2074 * and that becomes it's address [X < 128] or its unauthorized address
2075 * [X | 0x80].
2076 *
2077 * We add 1 as an offset to the one-based USB-stack port number
2078 * (zero-based wusb virtual port index) for two reasons: (a) dev addr
2079 * 0 is reserved by USB for default address; (b) Linux's USB stack
2080 * uses always #1 for the root hub of the controller. So USB stack's
2081 * port #1, which is wusb virtual-port #0 has address #2.
2082 *
2083 * Devices connected under xHCI are not as simple.  The host controller
2084 * supports virtualization, so the hardware assigns device addresses and
2085 * the HCD must setup data structures before issuing a set address
2086 * command to the hardware.
2087 */
2088static void choose_devnum(struct usb_device *udev)
2089{
2090	int		devnum;
2091	struct usb_bus	*bus = udev->bus;
2092
2093	/* be safe when more hub events are proceed in parallel */
2094	mutex_lock(&bus->devnum_next_mutex);
2095	if (udev->wusb) {
2096		devnum = udev->portnum + 1;
2097		BUG_ON(test_bit(devnum, bus->devmap.devicemap));
2098	} else {
2099		/* Try to allocate the next devnum beginning at
2100		 * bus->devnum_next. */
2101		devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
2102					    bus->devnum_next);
2103		if (devnum >= 128)
2104			devnum = find_next_zero_bit(bus->devmap.devicemap,
2105						    128, 1);
2106		bus->devnum_next = (devnum >= 127 ? 1 : devnum + 1);
2107	}
2108	if (devnum < 128) {
2109		set_bit(devnum, bus->devmap.devicemap);
2110		udev->devnum = devnum;
2111	}
2112	mutex_unlock(&bus->devnum_next_mutex);
2113}
2114
2115static void release_devnum(struct usb_device *udev)
2116{
2117	if (udev->devnum > 0) {
2118		clear_bit(udev->devnum, udev->bus->devmap.devicemap);
2119		udev->devnum = -1;
2120	}
2121}
2122
2123static void update_devnum(struct usb_device *udev, int devnum)
2124{
2125	/* The address for a WUSB device is managed by wusbcore. */
2126	if (!udev->wusb)
2127		udev->devnum = devnum;
2128	if (!udev->devaddr)
2129		udev->devaddr = (u8)devnum;
2130}
2131
2132static void hub_free_dev(struct usb_device *udev)
2133{
2134	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2135
2136	/* Root hubs aren't real devices, so don't free HCD resources */
2137	if (hcd->driver->free_dev && udev->parent)
2138		hcd->driver->free_dev(hcd, udev);
2139}
2140
2141static void hub_disconnect_children(struct usb_device *udev)
2142{
2143	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
2144	int i;
2145
2146	/* Free up all the children before we remove this device */
2147	for (i = 0; i < udev->maxchild; i++) {
2148		if (hub->ports[i]->child)
2149			usb_disconnect(&hub->ports[i]->child);
2150	}
2151}
2152
2153/**
2154 * usb_disconnect - disconnect a device (usbcore-internal)
2155 * @pdev: pointer to device being disconnected
2156 * Context: !in_interrupt ()
2157 *
2158 * Something got disconnected. Get rid of it and all of its children.
2159 *
2160 * If *pdev is a normal device then the parent hub must already be locked.
2161 * If *pdev is a root hub then the caller must hold the usb_bus_idr_lock,
2162 * which protects the set of root hubs as well as the list of buses.
2163 *
2164 * Only hub drivers (including virtual root hub drivers for host
2165 * controllers) should ever call this.
2166 *
2167 * This call is synchronous, and may not be used in an interrupt context.
2168 */
2169void usb_disconnect(struct usb_device **pdev)
2170{
2171	struct usb_port *port_dev = NULL;
2172	struct usb_device *udev = *pdev;
2173	struct usb_hub *hub = NULL;
2174	int port1 = 1;
2175
2176	/* mark the device as inactive, so any further urb submissions for
2177	 * this device (and any of its children) will fail immediately.
2178	 * this quiesces everything except pending urbs.
2179	 */
2180	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2181	dev_info(&udev->dev, "USB disconnect, device number %d\n",
2182			udev->devnum);
2183
2184	/*
2185	 * Ensure that the pm runtime code knows that the USB device
2186	 * is in the process of being disconnected.
2187	 */
2188	pm_runtime_barrier(&udev->dev);
2189
2190	usb_lock_device(udev);
2191
2192	hub_disconnect_children(udev);
2193
2194	/* deallocate hcd/hardware state ... nuking all pending urbs and
2195	 * cleaning up all state associated with the current configuration
2196	 * so that the hardware is now fully quiesced.
2197	 */
2198	dev_dbg(&udev->dev, "unregistering device\n");
2199	usb_disable_device(udev, 0);
2200	usb_hcd_synchronize_unlinks(udev);
2201
2202	if (udev->parent) {
2203		port1 = udev->portnum;
2204		hub = usb_hub_to_struct_hub(udev->parent);
2205		port_dev = hub->ports[port1 - 1];
2206
2207		sysfs_remove_link(&udev->dev.kobj, "port");
2208		sysfs_remove_link(&port_dev->dev.kobj, "device");
2209
2210		/*
2211		 * As usb_port_runtime_resume() de-references udev, make
2212		 * sure no resumes occur during removal
2213		 */
2214		if (!test_and_set_bit(port1, hub->child_usage_bits))
2215			pm_runtime_get_sync(&port_dev->dev);
2216	}
2217
2218	usb_remove_ep_devs(&udev->ep0);
2219	usb_unlock_device(udev);
2220
2221	/* Unregister the device.  The device driver is responsible
2222	 * for de-configuring the device and invoking the remove-device
2223	 * notifier chain (used by usbfs and possibly others).
2224	 */
2225	device_del(&udev->dev);
2226
2227	/* Free the device number and delete the parent's children[]
2228	 * (or root_hub) pointer.
2229	 */
2230	release_devnum(udev);
2231
2232	/* Avoid races with recursively_mark_NOTATTACHED() */
2233	spin_lock_irq(&device_state_lock);
2234	*pdev = NULL;
2235	spin_unlock_irq(&device_state_lock);
2236
2237	if (port_dev && test_and_clear_bit(port1, hub->child_usage_bits))
2238		pm_runtime_put(&port_dev->dev);
2239
2240	hub_free_dev(udev);
2241
2242	put_device(&udev->dev);
2243}
2244
2245#ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
2246static void show_string(struct usb_device *udev, char *id, char *string)
2247{
2248	if (!string)
2249		return;
2250	dev_info(&udev->dev, "%s: %s\n", id, string);
2251}
2252
2253static void announce_device(struct usb_device *udev)
2254{
2255	u16 bcdDevice = le16_to_cpu(udev->descriptor.bcdDevice);
2256
2257	dev_info(&udev->dev,
2258		"New USB device found, idVendor=%04x, idProduct=%04x, bcdDevice=%2x.%02x\n",
2259		le16_to_cpu(udev->descriptor.idVendor),
2260		le16_to_cpu(udev->descriptor.idProduct),
2261		bcdDevice >> 8, bcdDevice & 0xff);
2262	dev_info(&udev->dev,
2263		"New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
2264		udev->descriptor.iManufacturer,
2265		udev->descriptor.iProduct,
2266		udev->descriptor.iSerialNumber);
2267	show_string(udev, "Product", udev->product);
2268	show_string(udev, "Manufacturer", udev->manufacturer);
2269	show_string(udev, "SerialNumber", udev->serial);
2270}
2271#else
2272static inline void announce_device(struct usb_device *udev) { }
2273#endif
2274
2275
2276/**
2277 * usb_enumerate_device_otg - FIXME (usbcore-internal)
2278 * @udev: newly addressed device (in ADDRESS state)
2279 *
2280 * Finish enumeration for On-The-Go devices
2281 *
2282 * Return: 0 if successful. A negative error code otherwise.
2283 */
2284static int usb_enumerate_device_otg(struct usb_device *udev)
2285{
2286	int err = 0;
2287
2288#ifdef	CONFIG_USB_OTG
2289	/*
2290	 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
2291	 * to wake us after we've powered off VBUS; and HNP, switching roles
2292	 * "host" to "peripheral".  The OTG descriptor helps figure this out.
2293	 */
2294	if (!udev->bus->is_b_host
2295			&& udev->config
2296			&& udev->parent == udev->bus->root_hub) {
2297		struct usb_otg_descriptor	*desc = NULL;
2298		struct usb_bus			*bus = udev->bus;
2299		unsigned			port1 = udev->portnum;
2300
2301		/* descriptor may appear anywhere in config */
2302		err = __usb_get_extra_descriptor(udev->rawdescriptors[0],
2303				le16_to_cpu(udev->config[0].desc.wTotalLength),
2304				USB_DT_OTG, (void **) &desc, sizeof(*desc));
2305		if (err || !(desc->bmAttributes & USB_OTG_HNP))
2306			return 0;
2307
2308		dev_info(&udev->dev, "Dual-Role OTG device on %sHNP port\n",
2309					(port1 == bus->otg_port) ? "" : "non-");
2310
2311		/* enable HNP before suspend, it's simpler */
2312		if (port1 == bus->otg_port) {
2313			bus->b_hnp_enable = 1;
2314			err = usb_control_msg(udev,
2315				usb_sndctrlpipe(udev, 0),
2316				USB_REQ_SET_FEATURE, 0,
2317				USB_DEVICE_B_HNP_ENABLE,
2318				0, NULL, 0,
2319				USB_CTRL_SET_TIMEOUT);
2320			if (err < 0) {
2321				/*
2322				 * OTG MESSAGE: report errors here,
2323				 * customize to match your product.
2324				 */
2325				dev_err(&udev->dev, "can't set HNP mode: %d\n",
2326									err);
2327				bus->b_hnp_enable = 0;
2328			}
2329		} else if (desc->bLength == sizeof
2330				(struct usb_otg_descriptor)) {
2331			/* Set a_alt_hnp_support for legacy otg device */
2332			err = usb_control_msg(udev,
2333				usb_sndctrlpipe(udev, 0),
2334				USB_REQ_SET_FEATURE, 0,
2335				USB_DEVICE_A_ALT_HNP_SUPPORT,
2336				0, NULL, 0,
2337				USB_CTRL_SET_TIMEOUT);
2338			if (err < 0)
2339				dev_err(&udev->dev,
2340					"set a_alt_hnp_support failed: %d\n",
2341					err);
2342		}
2343	}
2344#endif
2345	return err;
2346}
2347
2348
2349/**
2350 * usb_enumerate_device - Read device configs/intfs/otg (usbcore-internal)
2351 * @udev: newly addressed device (in ADDRESS state)
2352 *
2353 * This is only called by usb_new_device() and usb_authorize_device()
2354 * and FIXME -- all comments that apply to them apply here wrt to
2355 * environment.
2356 *
2357 * If the device is WUSB and not authorized, we don't attempt to read
2358 * the string descriptors, as they will be errored out by the device
2359 * until it has been authorized.
2360 *
2361 * Return: 0 if successful. A negative error code otherwise.
2362 */
2363static int usb_enumerate_device(struct usb_device *udev)
2364{
2365	int err;
2366	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2367
2368	if (udev->config == NULL) {
2369		err = usb_get_configuration(udev);
2370		if (err < 0) {
2371			if (err != -ENODEV)
2372				dev_err(&udev->dev, "can't read configurations, error %d\n",
2373						err);
2374			return err;
2375		}
2376	}
2377
2378	/* read the standard strings and cache them if present */
2379	udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
2380	udev->manufacturer = usb_cache_string(udev,
2381					      udev->descriptor.iManufacturer);
2382	udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
2383
2384	err = usb_enumerate_device_otg(udev);
2385	if (err < 0)
2386		return err;
2387
2388	if (IS_ENABLED(CONFIG_USB_OTG_WHITELIST) && hcd->tpl_support &&
2389		!is_targeted(udev)) {
2390		/* Maybe it can talk to us, though we can't talk to it.
2391		 * (Includes HNP test device.)
2392		 */
2393		if (IS_ENABLED(CONFIG_USB_OTG) && (udev->bus->b_hnp_enable
2394			|| udev->bus->is_b_host)) {
2395			err = usb_port_suspend(udev, PMSG_AUTO_SUSPEND);
2396			if (err < 0)
2397				dev_dbg(&udev->dev, "HNP fail, %d\n", err);
2398		}
2399		return -ENOTSUPP;
2400	}
2401
2402	usb_detect_interface_quirks(udev);
2403
2404	return 0;
2405}
2406
2407static void set_usb_port_removable(struct usb_device *udev)
2408{
2409	struct usb_device *hdev = udev->parent;
2410	struct usb_hub *hub;
2411	u8 port = udev->portnum;
2412	u16 wHubCharacteristics;
2413	bool removable = true;
2414
2415	if (!hdev)
2416		return;
2417
2418	hub = usb_hub_to_struct_hub(udev->parent);
2419
2420	/*
2421	 * If the platform firmware has provided information about a port,
2422	 * use that to determine whether it's removable.
2423	 */
2424	switch (hub->ports[udev->portnum - 1]->connect_type) {
2425	case USB_PORT_CONNECT_TYPE_HOT_PLUG:
2426		udev->removable = USB_DEVICE_REMOVABLE;
2427		return;
2428	case USB_PORT_CONNECT_TYPE_HARD_WIRED:
2429	case USB_PORT_NOT_USED:
2430		udev->removable = USB_DEVICE_FIXED;
2431		return;
2432	default:
2433		break;
2434	}
2435
2436	/*
2437	 * Otherwise, check whether the hub knows whether a port is removable
2438	 * or not
2439	 */
2440	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2441
2442	if (!(wHubCharacteristics & HUB_CHAR_COMPOUND))
2443		return;
2444
2445	if (hub_is_superspeed(hdev)) {
2446		if (le16_to_cpu(hub->descriptor->u.ss.DeviceRemovable)
2447				& (1 << port))
2448			removable = false;
2449	} else {
2450		if (hub->descriptor->u.hs.DeviceRemovable[port / 8] & (1 << (port % 8)))
2451			removable = false;
2452	}
2453
2454	if (removable)
2455		udev->removable = USB_DEVICE_REMOVABLE;
2456	else
2457		udev->removable = USB_DEVICE_FIXED;
2458
2459}
2460
2461/**
2462 * usb_new_device - perform initial device setup (usbcore-internal)
2463 * @udev: newly addressed device (in ADDRESS state)
2464 *
2465 * This is called with devices which have been detected but not fully
2466 * enumerated.  The device descriptor is available, but not descriptors
2467 * for any device configuration.  The caller must have locked either
2468 * the parent hub (if udev is a normal device) or else the
2469 * usb_bus_idr_lock (if udev is a root hub).  The parent's pointer to
2470 * udev has already been installed, but udev is not yet visible through
2471 * sysfs or other filesystem code.
2472 *
2473 * This call is synchronous, and may not be used in an interrupt context.
2474 *
2475 * Only the hub driver or root-hub registrar should ever call this.
2476 *
2477 * Return: Whether the device is configured properly or not. Zero if the
2478 * interface was registered with the driver core; else a negative errno
2479 * value.
2480 *
2481 */
2482int usb_new_device(struct usb_device *udev)
2483{
2484	int err;
2485
2486	if (udev->parent) {
2487		/* Initialize non-root-hub device wakeup to disabled;
2488		 * device (un)configuration controls wakeup capable
2489		 * sysfs power/wakeup controls wakeup enabled/disabled
2490		 */
2491		device_init_wakeup(&udev->dev, 0);
2492	}
2493
2494	/* Tell the runtime-PM framework the device is active */
2495	pm_runtime_set_active(&udev->dev);
2496	pm_runtime_get_noresume(&udev->dev);
2497	pm_runtime_use_autosuspend(&udev->dev);
2498	pm_runtime_enable(&udev->dev);
2499
2500	/* By default, forbid autosuspend for all devices.  It will be
2501	 * allowed for hubs during binding.
2502	 */
2503	usb_disable_autosuspend(udev);
2504
2505	err = usb_enumerate_device(udev);	/* Read descriptors */
2506	if (err < 0)
2507		goto fail;
2508	dev_dbg(&udev->dev, "udev %d, busnum %d, minor = %d\n",
2509			udev->devnum, udev->bus->busnum,
2510			(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2511	/* export the usbdev device-node for libusb */
2512	udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
2513			(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2514
2515	/* Tell the world! */
2516	announce_device(udev);
2517
2518	if (udev->serial)
2519		add_device_randomness(udev->serial, strlen(udev->serial));
2520	if (udev->product)
2521		add_device_randomness(udev->product, strlen(udev->product));
2522	if (udev->manufacturer)
2523		add_device_randomness(udev->manufacturer,
2524				      strlen(udev->manufacturer));
2525
2526	device_enable_async_suspend(&udev->dev);
2527
2528	/* check whether the hub or firmware marks this port as non-removable */
2529	if (udev->parent)
2530		set_usb_port_removable(udev);
2531
2532	/* Register the device.  The device driver is responsible
2533	 * for configuring the device and invoking the add-device
2534	 * notifier chain (used by usbfs and possibly others).
2535	 */
2536	err = device_add(&udev->dev);
2537	if (err) {
2538		dev_err(&udev->dev, "can't device_add, error %d\n", err);
2539		goto fail;
2540	}
2541
2542	/* Create link files between child device and usb port device. */
2543	if (udev->parent) {
2544		struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
2545		int port1 = udev->portnum;
2546		struct usb_port	*port_dev = hub->ports[port1 - 1];
2547
2548		err = sysfs_create_link(&udev->dev.kobj,
2549				&port_dev->dev.kobj, "port");
2550		if (err)
2551			goto fail;
2552
2553		err = sysfs_create_link(&port_dev->dev.kobj,
2554				&udev->dev.kobj, "device");
2555		if (err) {
2556			sysfs_remove_link(&udev->dev.kobj, "port");
2557			goto fail;
2558		}
2559
2560		if (!test_and_set_bit(port1, hub->child_usage_bits))
2561			pm_runtime_get_sync(&port_dev->dev);
2562	}
2563
2564	(void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev);
2565	usb_mark_last_busy(udev);
2566	pm_runtime_put_sync_autosuspend(&udev->dev);
2567	return err;
2568
2569fail:
2570	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2571	pm_runtime_disable(&udev->dev);
2572	pm_runtime_set_suspended(&udev->dev);
2573	return err;
2574}
2575
2576
2577/**
2578 * usb_deauthorize_device - deauthorize a device (usbcore-internal)
2579 * @usb_dev: USB device
2580 *
2581 * Move the USB device to a very basic state where interfaces are disabled
2582 * and the device is in fact unconfigured and unusable.
2583 *
2584 * We share a lock (that we have) with device_del(), so we need to
2585 * defer its call.
2586 *
2587 * Return: 0.
2588 */
2589int usb_deauthorize_device(struct usb_device *usb_dev)
2590{
2591	usb_lock_device(usb_dev);
2592	if (usb_dev->authorized == 0)
2593		goto out_unauthorized;
2594
2595	usb_dev->authorized = 0;
2596	usb_set_configuration(usb_dev, -1);
2597
2598out_unauthorized:
2599	usb_unlock_device(usb_dev);
2600	return 0;
2601}
2602
2603
2604int usb_authorize_device(struct usb_device *usb_dev)
2605{
2606	int result = 0, c;
2607
2608	usb_lock_device(usb_dev);
2609	if (usb_dev->authorized == 1)
2610		goto out_authorized;
2611
2612	result = usb_autoresume_device(usb_dev);
2613	if (result < 0) {
2614		dev_err(&usb_dev->dev,
2615			"can't autoresume for authorization: %d\n", result);
2616		goto error_autoresume;
2617	}
2618
2619	if (usb_dev->wusb) {
2620		result = usb_get_device_descriptor(usb_dev, sizeof(usb_dev->descriptor));
2621		if (result < 0) {
2622			dev_err(&usb_dev->dev, "can't re-read device descriptor for "
2623				"authorization: %d\n", result);
2624			goto error_device_descriptor;
2625		}
2626	}
2627
2628	usb_dev->authorized = 1;
2629	/* Choose and set the configuration.  This registers the interfaces
2630	 * with the driver core and lets interface drivers bind to them.
2631	 */
2632	c = usb_choose_configuration(usb_dev);
2633	if (c >= 0) {
2634		result = usb_set_configuration(usb_dev, c);
2635		if (result) {
2636			dev_err(&usb_dev->dev,
2637				"can't set config #%d, error %d\n", c, result);
2638			/* This need not be fatal.  The user can try to
2639			 * set other configurations. */
2640		}
2641	}
2642	dev_info(&usb_dev->dev, "authorized to connect\n");
2643
2644error_device_descriptor:
2645	usb_autosuspend_device(usb_dev);
2646error_autoresume:
2647out_authorized:
2648	usb_unlock_device(usb_dev);	/* complements locktree */
2649	return result;
2650}
2651
2652/*
2653 * Return 1 if port speed is SuperSpeedPlus, 0 otherwise
2654 * check it from the link protocol field of the current speed ID attribute.
2655 * current speed ID is got from ext port status request. Sublink speed attribute
2656 * table is returned with the hub BOS SSP device capability descriptor
2657 */
2658static int port_speed_is_ssp(struct usb_device *hdev, int speed_id)
2659{
2660	int ssa_count;
2661	u32 ss_attr;
2662	int i;
2663	struct usb_ssp_cap_descriptor *ssp_cap = hdev->bos->ssp_cap;
2664
2665	if (!ssp_cap)
2666		return 0;
2667
2668	ssa_count = le32_to_cpu(ssp_cap->bmAttributes) &
2669		USB_SSP_SUBLINK_SPEED_ATTRIBS;
2670
2671	for (i = 0; i <= ssa_count; i++) {
2672		ss_attr = le32_to_cpu(ssp_cap->bmSublinkSpeedAttr[i]);
2673		if (speed_id == (ss_attr & USB_SSP_SUBLINK_SPEED_SSID))
2674			return !!(ss_attr & USB_SSP_SUBLINK_SPEED_LP);
2675	}
2676	return 0;
2677}
2678
2679/* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
2680static unsigned hub_is_wusb(struct usb_hub *hub)
2681{
2682	struct usb_hcd *hcd;
2683	if (hub->hdev->parent != NULL)  /* not a root hub? */
2684		return 0;
2685	hcd = bus_to_hcd(hub->hdev->bus);
2686	return hcd->wireless;
2687}
2688
2689
2690#define PORT_RESET_TRIES	5
2691#define SET_ADDRESS_TRIES	2
2692#define GET_DESCRIPTOR_TRIES	2
2693#define SET_CONFIG_TRIES	(2 * (use_both_schemes + 1))
2694#define USE_NEW_SCHEME(i, scheme)	((i) / 2 == (int)scheme)
2695
2696#define HUB_ROOT_RESET_TIME	60	/* times are in msec */
2697#define HUB_SHORT_RESET_TIME	10
2698#define HUB_BH_RESET_TIME	50
2699#define HUB_LONG_RESET_TIME	200
2700#define HUB_RESET_TIMEOUT	800
2701
2702/*
2703 * "New scheme" enumeration causes an extra state transition to be
2704 * exposed to an xhci host and causes USB3 devices to receive control
2705 * commands in the default state.  This has been seen to cause
2706 * enumeration failures, so disable this enumeration scheme for USB3
2707 * devices.
2708 */
2709static bool use_new_scheme(struct usb_device *udev, int retry,
2710			   struct usb_port *port_dev)
2711{
2712	int old_scheme_first_port =
2713		port_dev->quirks & USB_PORT_QUIRK_OLD_SCHEME;
2714	int quick_enumeration = (udev->speed == USB_SPEED_HIGH);
2715
2716	if (udev->speed >= USB_SPEED_SUPER)
2717		return false;
2718
2719	return USE_NEW_SCHEME(retry, old_scheme_first_port || old_scheme_first
2720			      || quick_enumeration);
2721}
2722
2723/* Is a USB 3.0 port in the Inactive or Compliance Mode state?
2724 * Port warm reset is required to recover
2725 */
2726static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
2727		u16 portstatus)
2728{
2729	u16 link_state;
2730
2731	if (!hub_is_superspeed(hub->hdev))
2732		return false;
2733
2734	if (test_bit(port1, hub->warm_reset_bits))
2735		return true;
2736
2737	link_state = portstatus & USB_PORT_STAT_LINK_STATE;
2738	return link_state == USB_SS_PORT_LS_SS_INACTIVE
2739		|| link_state == USB_SS_PORT_LS_COMP_MOD;
2740}
2741
2742static int hub_port_wait_reset(struct usb_hub *hub, int port1,
2743			struct usb_device *udev, unsigned int delay, bool warm)
2744{
2745	int delay_time, ret;
2746	u16 portstatus;
2747	u16 portchange;
2748	u32 ext_portstatus = 0;
2749
2750	for (delay_time = 0;
2751			delay_time < HUB_RESET_TIMEOUT;
2752			delay_time += delay) {
2753		/* wait to give the device a chance to reset */
2754		msleep(delay);
2755
2756		/* read and decode port status */
2757		if (hub_is_superspeedplus(hub->hdev))
2758			ret = hub_ext_port_status(hub, port1,
2759						  HUB_EXT_PORT_STATUS,
2760						  &portstatus, &portchange,
2761						  &ext_portstatus);
2762		else
2763			ret = hub_port_status(hub, port1, &portstatus,
2764					      &portchange);
2765		if (ret < 0)
2766			return ret;
2767
2768		/*
2769		 * The port state is unknown until the reset completes.
2770		 *
2771		 * On top of that, some chips may require additional time
2772		 * to re-establish a connection after the reset is complete,
2773		 * so also wait for the connection to be re-established.
2774		 */
2775		if (!(portstatus & USB_PORT_STAT_RESET) &&
2776		    (portstatus & USB_PORT_STAT_CONNECTION))
2777			break;
2778
2779		/* switch to the long delay after two short delay failures */
2780		if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
2781			delay = HUB_LONG_RESET_TIME;
2782
2783		dev_dbg(&hub->ports[port1 - 1]->dev,
2784				"not %sreset yet, waiting %dms\n",
2785				warm ? "warm " : "", delay);
2786	}
2787
2788	if ((portstatus & USB_PORT_STAT_RESET))
2789		return -EBUSY;
2790
2791	if (hub_port_warm_reset_required(hub, port1, portstatus))
2792		return -ENOTCONN;
2793
2794	/* Device went away? */
2795	if (!(portstatus & USB_PORT_STAT_CONNECTION))
2796		return -ENOTCONN;
2797
2798	/* Retry if connect change is set but status is still connected.
2799	 * A USB 3.0 connection may bounce if multiple warm resets were issued,
2800	 * but the device may have successfully re-connected. Ignore it.
2801	 */
2802	if (!hub_is_superspeed(hub->hdev) &&
2803	    (portchange & USB_PORT_STAT_C_CONNECTION)) {
2804		usb_clear_port_feature(hub->hdev, port1,
2805				       USB_PORT_FEAT_C_CONNECTION);
2806		return -EAGAIN;
2807	}
2808
2809	if (!(portstatus & USB_PORT_STAT_ENABLE))
2810		return -EBUSY;
2811
2812	if (!udev)
2813		return 0;
2814
2815	if (hub_is_superspeedplus(hub->hdev)) {
2816		/* extended portstatus Rx and Tx lane count are zero based */
2817		udev->rx_lanes = USB_EXT_PORT_RX_LANES(ext_portstatus) + 1;
2818		udev->tx_lanes = USB_EXT_PORT_TX_LANES(ext_portstatus) + 1;
2819	} else {
2820		udev->rx_lanes = 1;
2821		udev->tx_lanes = 1;
2822	}
2823	if (hub_is_wusb(hub))
2824		udev->speed = USB_SPEED_WIRELESS;
2825	else if (hub_is_superspeedplus(hub->hdev) &&
2826		 port_speed_is_ssp(hub->hdev, ext_portstatus &
2827				   USB_EXT_PORT_STAT_RX_SPEED_ID))
2828		udev->speed = USB_SPEED_SUPER_PLUS;
2829	else if (hub_is_superspeed(hub->hdev))
2830		udev->speed = USB_SPEED_SUPER;
2831	else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
2832		udev->speed = USB_SPEED_HIGH;
2833	else if (portstatus & USB_PORT_STAT_LOW_SPEED)
2834		udev->speed = USB_SPEED_LOW;
2835	else
2836		udev->speed = USB_SPEED_FULL;
2837	return 0;
2838}
2839
2840/* Handle port reset and port warm(BH) reset (for USB3 protocol ports) */
2841static int hub_port_reset(struct usb_hub *hub, int port1,
2842			struct usb_device *udev, unsigned int delay, bool warm)
2843{
2844	int i, status;
2845	u16 portchange, portstatus;
2846	struct usb_port *port_dev = hub->ports[port1 - 1];
2847	int reset_recovery_time;
2848
2849	if (!hub_is_superspeed(hub->hdev)) {
2850		if (warm) {
2851			dev_err(hub->intfdev, "only USB3 hub support "
2852						"warm reset\n");
2853			return -EINVAL;
2854		}
2855		/* Block EHCI CF initialization during the port reset.
2856		 * Some companion controllers don't like it when they mix.
2857		 */
2858		down_read(&ehci_cf_port_reset_rwsem);
2859	} else if (!warm) {
2860		/*
2861		 * If the caller hasn't explicitly requested a warm reset,
2862		 * double check and see if one is needed.
2863		 */
2864		if (hub_port_status(hub, port1, &portstatus, &portchange) == 0)
2865			if (hub_port_warm_reset_required(hub, port1,
2866							portstatus))
2867				warm = true;
2868	}
2869	clear_bit(port1, hub->warm_reset_bits);
2870
2871	/* Reset the port */
2872	for (i = 0; i < PORT_RESET_TRIES; i++) {
2873		status = set_port_feature(hub->hdev, port1, (warm ?
2874					USB_PORT_FEAT_BH_PORT_RESET :
2875					USB_PORT_FEAT_RESET));
2876		if (status == -ENODEV) {
2877			;	/* The hub is gone */
2878		} else if (status) {
2879			dev_err(&port_dev->dev,
2880					"cannot %sreset (err = %d)\n",
2881					warm ? "warm " : "", status);
2882		} else {
2883			status = hub_port_wait_reset(hub, port1, udev, delay,
2884								warm);
2885			if (status && status != -ENOTCONN && status != -ENODEV)
2886				dev_dbg(hub->intfdev,
2887						"port_wait_reset: err = %d\n",
2888						status);
2889		}
2890
2891		/* Check for disconnect or reset */
2892		if (status == 0 || status == -ENOTCONN || status == -ENODEV) {
2893			usb_clear_port_feature(hub->hdev, port1,
2894					USB_PORT_FEAT_C_RESET);
2895
2896			if (!hub_is_superspeed(hub->hdev))
2897				goto done;
2898
2899			usb_clear_port_feature(hub->hdev, port1,
2900					USB_PORT_FEAT_C_BH_PORT_RESET);
2901			usb_clear_port_feature(hub->hdev, port1,
2902					USB_PORT_FEAT_C_PORT_LINK_STATE);
2903
2904			if (udev)
2905				usb_clear_port_feature(hub->hdev, port1,
2906					USB_PORT_FEAT_C_CONNECTION);
2907
2908			/*
2909			 * If a USB 3.0 device migrates from reset to an error
2910			 * state, re-issue the warm reset.
2911			 */
2912			if (hub_port_status(hub, port1,
2913					&portstatus, &portchange) < 0)
2914				goto done;
2915
2916			if (!hub_port_warm_reset_required(hub, port1,
2917					portstatus))
2918				goto done;
2919
2920			/*
2921			 * If the port is in SS.Inactive or Compliance Mode, the
2922			 * hot or warm reset failed.  Try another warm reset.
2923			 */
2924			if (!warm) {
2925				dev_dbg(&port_dev->dev,
2926						"hot reset failed, warm reset\n");
2927				warm = true;
2928			}
2929		}
2930
2931		dev_dbg(&port_dev->dev,
2932				"not enabled, trying %sreset again...\n",
2933				warm ? "warm " : "");
2934		delay = HUB_LONG_RESET_TIME;
2935	}
2936
2937	dev_err(&port_dev->dev, "Cannot enable. Maybe the USB cable is bad?\n");
2938
2939done:
2940	if (status == 0) {
2941		if (port_dev->quirks & USB_PORT_QUIRK_FAST_ENUM)
2942			usleep_range(10000, 12000);
2943		else {
2944			/* TRSTRCY = 10 ms; plus some extra */
2945			reset_recovery_time = 10 + 40;
2946
2947			/* Hub needs extra delay after resetting its port. */
2948			if (hub->hdev->quirks & USB_QUIRK_HUB_SLOW_RESET)
2949				reset_recovery_time += 100;
2950
2951			msleep(reset_recovery_time);
2952		}
2953
2954		if (udev) {
2955			struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2956
2957			update_devnum(udev, 0);
2958			/* The xHC may think the device is already reset,
2959			 * so ignore the status.
2960			 */
2961			if (hcd->driver->reset_device)
2962				hcd->driver->reset_device(hcd, udev);
2963
2964			usb_set_device_state(udev, USB_STATE_DEFAULT);
2965		}
2966	} else {
2967		if (udev)
2968			usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2969	}
2970
2971	if (!hub_is_superspeed(hub->hdev))
2972		up_read(&ehci_cf_port_reset_rwsem);
2973
2974	return status;
2975}
2976
2977/* Check if a port is power on */
2978static int port_is_power_on(struct usb_hub *hub, unsigned portstatus)
2979{
2980	int ret = 0;
2981
2982	if (hub_is_superspeed(hub->hdev)) {
2983		if (portstatus & USB_SS_PORT_STAT_POWER)
2984			ret = 1;
2985	} else {
2986		if (portstatus & USB_PORT_STAT_POWER)
2987			ret = 1;
2988	}
2989
2990	return ret;
2991}
2992
2993static void usb_lock_port(struct usb_port *port_dev)
2994		__acquires(&port_dev->status_lock)
2995{
2996	mutex_lock(&port_dev->status_lock);
2997	__acquire(&port_dev->status_lock);
2998}
2999
3000static void usb_unlock_port(struct usb_port *port_dev)
3001		__releases(&port_dev->status_lock)
3002{
3003	mutex_unlock(&port_dev->status_lock);
3004	__release(&port_dev->status_lock);
3005}
3006
3007#ifdef	CONFIG_PM
3008
3009/* Check if a port is suspended(USB2.0 port) or in U3 state(USB3.0 port) */
3010static int port_is_suspended(struct usb_hub *hub, unsigned portstatus)
3011{
3012	int ret = 0;
3013
3014	if (hub_is_superspeed(hub->hdev)) {
3015		if ((portstatus & USB_PORT_STAT_LINK_STATE)
3016				== USB_SS_PORT_LS_U3)
3017			ret = 1;
3018	} else {
3019		if (portstatus & USB_PORT_STAT_SUSPEND)
3020			ret = 1;
3021	}
3022
3023	return ret;
3024}
3025
3026/* Determine whether the device on a port is ready for a normal resume,
3027 * is ready for a reset-resume, or should be disconnected.
3028 */
3029static int check_port_resume_type(struct usb_device *udev,
3030		struct usb_hub *hub, int port1,
3031		int status, u16 portchange, u16 portstatus)
3032{
3033	struct usb_port *port_dev = hub->ports[port1 - 1];
3034	int retries = 3;
3035
3036 retry:
3037	/* Is a warm reset needed to recover the connection? */
3038	if (status == 0 && udev->reset_resume
3039		&& hub_port_warm_reset_required(hub, port1, portstatus)) {
3040		/* pass */;
3041	}
3042	/* Is the device still present? */
3043	else if (status || port_is_suspended(hub, portstatus) ||
3044			!port_is_power_on(hub, portstatus)) {
3045		if (status >= 0)
3046			status = -ENODEV;
3047	} else if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
3048		if (retries--) {
3049			usleep_range(200, 300);
3050			status = hub_port_status(hub, port1, &portstatus,
3051							     &portchange);
3052			goto retry;
3053		}
3054		status = -ENODEV;
3055	}
3056
3057	/* Can't do a normal resume if the port isn't enabled,
3058	 * so try a reset-resume instead.
3059	 */
3060	else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
3061		if (udev->persist_enabled)
3062			udev->reset_resume = 1;
3063		else
3064			status = -ENODEV;
3065	}
3066
3067	if (status) {
3068		dev_dbg(&port_dev->dev, "status %04x.%04x after resume, %d\n",
3069				portchange, portstatus, status);
3070	} else if (udev->reset_resume) {
3071
3072		/* Late port handoff can set status-change bits */
3073		if (portchange & USB_PORT_STAT_C_CONNECTION)
3074			usb_clear_port_feature(hub->hdev, port1,
3075					USB_PORT_FEAT_C_CONNECTION);
3076		if (portchange & USB_PORT_STAT_C_ENABLE)
3077			usb_clear_port_feature(hub->hdev, port1,
3078					USB_PORT_FEAT_C_ENABLE);
3079	}
3080
3081	return status;
3082}
3083
3084int usb_disable_ltm(struct usb_device *udev)
3085{
3086	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3087
3088	/* Check if the roothub and device supports LTM. */
3089	if (!usb_device_supports_ltm(hcd->self.root_hub) ||
3090			!usb_device_supports_ltm(udev))
3091		return 0;
3092
3093	/* Clear Feature LTM Enable can only be sent if the device is
3094	 * configured.
3095	 */
3096	if (!udev->actconfig)
3097		return 0;
3098
3099	return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3100			USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
3101			USB_DEVICE_LTM_ENABLE, 0, NULL, 0,
3102			USB_CTRL_SET_TIMEOUT);
3103}
3104EXPORT_SYMBOL_GPL(usb_disable_ltm);
3105
3106void usb_enable_ltm(struct usb_device *udev)
3107{
3108	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3109
3110	/* Check if the roothub and device supports LTM. */
3111	if (!usb_device_supports_ltm(hcd->self.root_hub) ||
3112			!usb_device_supports_ltm(udev))
3113		return;
3114
3115	/* Set Feature LTM Enable can only be sent if the device is
3116	 * configured.
3117	 */
3118	if (!udev->actconfig)
3119		return;
3120
3121	usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3122			USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
3123			USB_DEVICE_LTM_ENABLE, 0, NULL, 0,
3124			USB_CTRL_SET_TIMEOUT);
3125}
3126EXPORT_SYMBOL_GPL(usb_enable_ltm);
3127
3128/*
3129 * usb_enable_remote_wakeup - enable remote wakeup for a device
3130 * @udev: target device
3131 *
3132 * For USB-2 devices: Set the device's remote wakeup feature.
3133 *
3134 * For USB-3 devices: Assume there's only one function on the device and
3135 * enable remote wake for the first interface.  FIXME if the interface
3136 * association descriptor shows there's more than one function.
3137 */
3138static int usb_enable_remote_wakeup(struct usb_device *udev)
3139{
3140	if (udev->speed < USB_SPEED_SUPER)
3141		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3142				USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
3143				USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0,
3144				USB_CTRL_SET_TIMEOUT);
3145	else
3146		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3147				USB_REQ_SET_FEATURE, USB_RECIP_INTERFACE,
3148				USB_INTRF_FUNC_SUSPEND,
3149				USB_INTRF_FUNC_SUSPEND_RW |
3150					USB_INTRF_FUNC_SUSPEND_LP,
3151				NULL, 0, USB_CTRL_SET_TIMEOUT);
3152}
3153
3154/*
3155 * usb_disable_remote_wakeup - disable remote wakeup for a device
3156 * @udev: target device
3157 *
3158 * For USB-2 devices: Clear the device's remote wakeup feature.
3159 *
3160 * For USB-3 devices: Assume there's only one function on the device and
3161 * disable remote wake for the first interface.  FIXME if the interface
3162 * association descriptor shows there's more than one function.
3163 */
3164static int usb_disable_remote_wakeup(struct usb_device *udev)
3165{
3166	if (udev->speed < USB_SPEED_SUPER)
3167		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3168				USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
3169				USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0,
3170				USB_CTRL_SET_TIMEOUT);
3171	else
3172		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3173				USB_REQ_SET_FEATURE, USB_RECIP_INTERFACE,
3174				USB_INTRF_FUNC_SUSPEND,	0, NULL, 0,
3175				USB_CTRL_SET_TIMEOUT);
3176}
3177
3178/* Count of wakeup-enabled devices at or below udev */
3179unsigned usb_wakeup_enabled_descendants(struct usb_device *udev)
3180{
3181	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
3182
3183	return udev->do_remote_wakeup +
3184			(hub ? hub->wakeup_enabled_descendants : 0);
3185}
3186EXPORT_SYMBOL_GPL(usb_wakeup_enabled_descendants);
3187
3188/*
3189 * usb_port_suspend - suspend a usb device's upstream port
3190 * @udev: device that's no longer in active use, not a root hub
3191 * Context: must be able to sleep; device not locked; pm locks held
3192 *
3193 * Suspends a USB device that isn't in active use, conserving power.
3194 * Devices may wake out of a suspend, if anything important happens,
3195 * using the remote wakeup mechanism.  They may also be taken out of
3196 * suspend by the host, using usb_port_resume().  It's also routine
3197 * to disconnect devices while they are suspended.
3198 *
3199 * This only affects the USB hardware for a device; its interfaces
3200 * (and, for hubs, child devices) must already have been suspended.
3201 *
3202 * Selective port suspend reduces power; most suspended devices draw
3203 * less than 500 uA.  It's also used in OTG, along with remote wakeup.
3204 * All devices below the suspended port are also suspended.
3205 *
3206 * Devices leave suspend state when the host wakes them up.  Some devices
3207 * also support "remote wakeup", where the device can activate the USB
3208 * tree above them to deliver data, such as a keypress or packet.  In
3209 * some cases, this wakes the USB host.
3210 *
3211 * Suspending OTG devices may trigger HNP, if that's been enabled
3212 * between a pair of dual-role devices.  That will change roles, such
3213 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
3214 *
3215 * Devices on USB hub ports have only one "suspend" state, corresponding
3216 * to ACPI D2, "may cause the device to lose some context".
3217 * State transitions include:
3218 *
3219 *   - suspend, resume ... when the VBUS power link stays live
3220 *   - suspend, disconnect ... VBUS lost
3221 *
3222 * Once VBUS drop breaks the circuit, the port it's using has to go through
3223 * normal re-enumeration procedures, starting with enabling VBUS power.
3224 * Other than re-initializing the hub (plug/unplug, except for root hubs),
3225 * Linux (2.6) currently has NO mechanisms to initiate that:  no hub_wq
3226 * timer, no SRP, no requests through sysfs.
3227 *
3228 * If Runtime PM isn't enabled or used, non-SuperSpeed devices may not get
3229 * suspended until their bus goes into global suspend (i.e., the root
3230 * hub is suspended).  Nevertheless, we change @udev->state to
3231 * USB_STATE_SUSPENDED as this is the device's "logical" state.  The actual
3232 * upstream port setting is stored in @udev->port_is_suspended.
3233 *
3234 * Returns 0 on success, else negative errno.
3235 */
3236int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
3237{
3238	struct usb_hub	*hub = usb_hub_to_struct_hub(udev->parent);
3239	struct usb_port *port_dev = hub->ports[udev->portnum - 1];
3240	int		port1 = udev->portnum;
3241	int		status;
3242	bool		really_suspend = true;
3243
3244	usb_lock_port(port_dev);
3245
3246	/* enable remote wakeup when appropriate; this lets the device
3247	 * wake up the upstream hub (including maybe the root hub).
3248	 *
3249	 * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
3250	 * we don't explicitly enable it here.
3251	 */
3252	if (udev->do_remote_wakeup) {
3253		status = usb_enable_remote_wakeup(udev);
3254		if (status) {
3255			dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
3256					status);
3257			/* bail if autosuspend is requested */
3258			if (PMSG_IS_AUTO(msg))
3259				goto err_wakeup;
3260		}
3261	}
3262
3263	/* disable USB2 hardware LPM */
3264	usb_disable_usb2_hardware_lpm(udev);
 
3265
3266	if (usb_disable_ltm(udev)) {
3267		dev_err(&udev->dev, "Failed to disable LTM before suspend\n");
3268		status = -ENOMEM;
3269		if (PMSG_IS_AUTO(msg))
3270			goto err_ltm;
3271	}
3272
3273	/* see 7.1.7.6 */
3274	if (hub_is_superspeed(hub->hdev))
3275		status = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_U3);
3276
3277	/*
3278	 * For system suspend, we do not need to enable the suspend feature
3279	 * on individual USB-2 ports.  The devices will automatically go
3280	 * into suspend a few ms after the root hub stops sending packets.
3281	 * The USB 2.0 spec calls this "global suspend".
3282	 *
3283	 * However, many USB hubs have a bug: They don't relay wakeup requests
3284	 * from a downstream port if the port's suspend feature isn't on.
3285	 * Therefore we will turn on the suspend feature if udev or any of its
3286	 * descendants is enabled for remote wakeup.
3287	 */
3288	else if (PMSG_IS_AUTO(msg) || usb_wakeup_enabled_descendants(udev) > 0)
3289		status = set_port_feature(hub->hdev, port1,
3290				USB_PORT_FEAT_SUSPEND);
3291	else {
3292		really_suspend = false;
3293		status = 0;
3294	}
3295	if (status) {
3296		dev_dbg(&port_dev->dev, "can't suspend, status %d\n", status);
3297
3298		/* Try to enable USB3 LTM again */
3299		usb_enable_ltm(udev);
3300 err_ltm:
3301		/* Try to enable USB2 hardware LPM again */
3302		usb_enable_usb2_hardware_lpm(udev);
 
3303
3304		if (udev->do_remote_wakeup)
3305			(void) usb_disable_remote_wakeup(udev);
3306 err_wakeup:
3307
3308		/* System sleep transitions should never fail */
3309		if (!PMSG_IS_AUTO(msg))
3310			status = 0;
3311	} else {
3312		dev_dbg(&udev->dev, "usb %ssuspend, wakeup %d\n",
3313				(PMSG_IS_AUTO(msg) ? "auto-" : ""),
3314				udev->do_remote_wakeup);
3315		if (really_suspend) {
3316			udev->port_is_suspended = 1;
3317
3318			/* device has up to 10 msec to fully suspend */
3319			msleep(10);
3320		}
3321		usb_set_device_state(udev, USB_STATE_SUSPENDED);
3322	}
3323
3324	if (status == 0 && !udev->do_remote_wakeup && udev->persist_enabled
3325			&& test_and_clear_bit(port1, hub->child_usage_bits))
3326		pm_runtime_put_sync(&port_dev->dev);
3327
3328	usb_mark_last_busy(hub->hdev);
3329
3330	usb_unlock_port(port_dev);
3331	return status;
3332}
3333
3334/*
3335 * If the USB "suspend" state is in use (rather than "global suspend"),
3336 * many devices will be individually taken out of suspend state using
3337 * special "resume" signaling.  This routine kicks in shortly after
3338 * hardware resume signaling is finished, either because of selective
3339 * resume (by host) or remote wakeup (by device) ... now see what changed
3340 * in the tree that's rooted at this device.
3341 *
3342 * If @udev->reset_resume is set then the device is reset before the
3343 * status check is done.
3344 */
3345static int finish_port_resume(struct usb_device *udev)
3346{
3347	int	status = 0;
3348	u16	devstatus = 0;
3349
3350	/* caller owns the udev device lock */
3351	dev_dbg(&udev->dev, "%s\n",
3352		udev->reset_resume ? "finish reset-resume" : "finish resume");
3353
3354	/* usb ch9 identifies four variants of SUSPENDED, based on what
3355	 * state the device resumes to.  Linux currently won't see the
3356	 * first two on the host side; they'd be inside hub_port_init()
3357	 * during many timeouts, but hub_wq can't suspend until later.
3358	 */
3359	usb_set_device_state(udev, udev->actconfig
3360			? USB_STATE_CONFIGURED
3361			: USB_STATE_ADDRESS);
3362
3363	/* 10.5.4.5 says not to reset a suspended port if the attached
3364	 * device is enabled for remote wakeup.  Hence the reset
3365	 * operation is carried out here, after the port has been
3366	 * resumed.
3367	 */
3368	if (udev->reset_resume) {
3369		/*
3370		 * If the device morphs or switches modes when it is reset,
3371		 * we don't want to perform a reset-resume.  We'll fail the
3372		 * resume, which will cause a logical disconnect, and then
3373		 * the device will be rediscovered.
3374		 */
3375 retry_reset_resume:
3376		if (udev->quirks & USB_QUIRK_RESET)
3377			status = -ENODEV;
3378		else
3379			status = usb_reset_and_verify_device(udev);
3380	}
3381
3382	/* 10.5.4.5 says be sure devices in the tree are still there.
3383	 * For now let's assume the device didn't go crazy on resume,
3384	 * and device drivers will know about any resume quirks.
3385	 */
3386	if (status == 0) {
3387		devstatus = 0;
3388		status = usb_get_std_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
3389
3390		/* If a normal resume failed, try doing a reset-resume */
3391		if (status && !udev->reset_resume && udev->persist_enabled) {
3392			dev_dbg(&udev->dev, "retry with reset-resume\n");
3393			udev->reset_resume = 1;
3394			goto retry_reset_resume;
3395		}
3396	}
3397
3398	if (status) {
3399		dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
3400				status);
3401	/*
3402	 * There are a few quirky devices which violate the standard
3403	 * by claiming to have remote wakeup enabled after a reset,
3404	 * which crash if the feature is cleared, hence check for
3405	 * udev->reset_resume
3406	 */
3407	} else if (udev->actconfig && !udev->reset_resume) {
3408		if (udev->speed < USB_SPEED_SUPER) {
3409			if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
3410				status = usb_disable_remote_wakeup(udev);
3411		} else {
3412			status = usb_get_std_status(udev, USB_RECIP_INTERFACE, 0,
3413					&devstatus);
3414			if (!status && devstatus & (USB_INTRF_STAT_FUNC_RW_CAP
3415					| USB_INTRF_STAT_FUNC_RW))
3416				status = usb_disable_remote_wakeup(udev);
3417		}
3418
3419		if (status)
3420			dev_dbg(&udev->dev,
3421				"disable remote wakeup, status %d\n",
3422				status);
3423		status = 0;
3424	}
3425	return status;
3426}
3427
3428/*
3429 * There are some SS USB devices which take longer time for link training.
3430 * XHCI specs 4.19.4 says that when Link training is successful, port
3431 * sets CCS bit to 1. So if SW reads port status before successful link
3432 * training, then it will not find device to be present.
3433 * USB Analyzer log with such buggy devices show that in some cases
3434 * device switch on the RX termination after long delay of host enabling
3435 * the VBUS. In few other cases it has been seen that device fails to
3436 * negotiate link training in first attempt. It has been
3437 * reported till now that few devices take as long as 2000 ms to train
3438 * the link after host enabling its VBUS and termination. Following
3439 * routine implements a 2000 ms timeout for link training. If in a case
3440 * link trains before timeout, loop will exit earlier.
3441 *
3442 * There are also some 2.0 hard drive based devices and 3.0 thumb
3443 * drives that, when plugged into a 2.0 only port, take a long
3444 * time to set CCS after VBUS enable.
3445 *
3446 * FIXME: If a device was connected before suspend, but was removed
3447 * while system was asleep, then the loop in the following routine will
3448 * only exit at timeout.
3449 *
3450 * This routine should only be called when persist is enabled.
3451 */
3452static int wait_for_connected(struct usb_device *udev,
3453		struct usb_hub *hub, int *port1,
3454		u16 *portchange, u16 *portstatus)
3455{
3456	int status = 0, delay_ms = 0;
3457
3458	while (delay_ms < 2000) {
3459		if (status || *portstatus & USB_PORT_STAT_CONNECTION)
3460			break;
3461		if (!port_is_power_on(hub, *portstatus)) {
3462			status = -ENODEV;
3463			break;
3464		}
3465		msleep(20);
3466		delay_ms += 20;
3467		status = hub_port_status(hub, *port1, portstatus, portchange);
3468	}
3469	dev_dbg(&udev->dev, "Waited %dms for CONNECT\n", delay_ms);
3470	return status;
3471}
3472
3473/*
3474 * usb_port_resume - re-activate a suspended usb device's upstream port
3475 * @udev: device to re-activate, not a root hub
3476 * Context: must be able to sleep; device not locked; pm locks held
3477 *
3478 * This will re-activate the suspended device, increasing power usage
3479 * while letting drivers communicate again with its endpoints.
3480 * USB resume explicitly guarantees that the power session between
3481 * the host and the device is the same as it was when the device
3482 * suspended.
3483 *
3484 * If @udev->reset_resume is set then this routine won't check that the
3485 * port is still enabled.  Furthermore, finish_port_resume() above will
3486 * reset @udev.  The end result is that a broken power session can be
3487 * recovered and @udev will appear to persist across a loss of VBUS power.
3488 *
3489 * For example, if a host controller doesn't maintain VBUS suspend current
3490 * during a system sleep or is reset when the system wakes up, all the USB
3491 * power sessions below it will be broken.  This is especially troublesome
3492 * for mass-storage devices containing mounted filesystems, since the
3493 * device will appear to have disconnected and all the memory mappings
3494 * to it will be lost.  Using the USB_PERSIST facility, the device can be
3495 * made to appear as if it had not disconnected.
3496 *
3497 * This facility can be dangerous.  Although usb_reset_and_verify_device() makes
3498 * every effort to insure that the same device is present after the
3499 * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
3500 * quite possible for a device to remain unaltered but its media to be
3501 * changed.  If the user replaces a flash memory card while the system is
3502 * asleep, he will have only himself to blame when the filesystem on the
3503 * new card is corrupted and the system crashes.
3504 *
3505 * Returns 0 on success, else negative errno.
3506 */
3507int usb_port_resume(struct usb_device *udev, pm_message_t msg)
3508{
3509	struct usb_hub	*hub = usb_hub_to_struct_hub(udev->parent);
3510	struct usb_port *port_dev = hub->ports[udev->portnum  - 1];
3511	int		port1 = udev->portnum;
3512	int		status;
3513	u16		portchange, portstatus;
3514
3515	if (!test_and_set_bit(port1, hub->child_usage_bits)) {
3516		status = pm_runtime_get_sync(&port_dev->dev);
3517		if (status < 0) {
3518			dev_dbg(&udev->dev, "can't resume usb port, status %d\n",
3519					status);
3520			return status;
3521		}
3522	}
3523
3524	usb_lock_port(port_dev);
3525
3526	/* Skip the initial Clear-Suspend step for a remote wakeup */
3527	status = hub_port_status(hub, port1, &portstatus, &portchange);
3528	if (status == 0 && !port_is_suspended(hub, portstatus)) {
3529		if (portchange & USB_PORT_STAT_C_SUSPEND)
3530			pm_wakeup_event(&udev->dev, 0);
3531		goto SuspendCleared;
3532	}
3533
3534	/* see 7.1.7.7; affects power usage, but not budgeting */
3535	if (hub_is_superspeed(hub->hdev))
3536		status = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_U0);
3537	else
3538		status = usb_clear_port_feature(hub->hdev,
3539				port1, USB_PORT_FEAT_SUSPEND);
3540	if (status) {
3541		dev_dbg(&port_dev->dev, "can't resume, status %d\n", status);
3542	} else {
3543		/* drive resume for USB_RESUME_TIMEOUT msec */
3544		dev_dbg(&udev->dev, "usb %sresume\n",
3545				(PMSG_IS_AUTO(msg) ? "auto-" : ""));
3546		msleep(USB_RESUME_TIMEOUT);
3547
3548		/* Virtual root hubs can trigger on GET_PORT_STATUS to
3549		 * stop resume signaling.  Then finish the resume
3550		 * sequence.
3551		 */
3552		status = hub_port_status(hub, port1, &portstatus, &portchange);
3553
3554		/* TRSMRCY = 10 msec */
3555		msleep(10);
3556	}
3557
3558 SuspendCleared:
3559	if (status == 0) {
3560		udev->port_is_suspended = 0;
3561		if (hub_is_superspeed(hub->hdev)) {
3562			if (portchange & USB_PORT_STAT_C_LINK_STATE)
3563				usb_clear_port_feature(hub->hdev, port1,
3564					USB_PORT_FEAT_C_PORT_LINK_STATE);
3565		} else {
3566			if (portchange & USB_PORT_STAT_C_SUSPEND)
3567				usb_clear_port_feature(hub->hdev, port1,
3568						USB_PORT_FEAT_C_SUSPEND);
3569		}
3570	}
3571
3572	if (udev->persist_enabled)
3573		status = wait_for_connected(udev, hub, &port1, &portchange,
3574				&portstatus);
3575
3576	status = check_port_resume_type(udev,
3577			hub, port1, status, portchange, portstatus);
3578	if (status == 0)
3579		status = finish_port_resume(udev);
3580	if (status < 0) {
3581		dev_dbg(&udev->dev, "can't resume, status %d\n", status);
3582		hub_port_logical_disconnect(hub, port1);
3583	} else  {
3584		/* Try to enable USB2 hardware LPM */
3585		usb_enable_usb2_hardware_lpm(udev);
 
3586
3587		/* Try to enable USB3 LTM */
3588		usb_enable_ltm(udev);
3589	}
3590
3591	usb_unlock_port(port_dev);
3592
3593	return status;
3594}
3595
3596int usb_remote_wakeup(struct usb_device *udev)
3597{
3598	int	status = 0;
3599
3600	usb_lock_device(udev);
3601	if (udev->state == USB_STATE_SUSPENDED) {
3602		dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
3603		status = usb_autoresume_device(udev);
3604		if (status == 0) {
3605			/* Let the drivers do their thing, then... */
3606			usb_autosuspend_device(udev);
3607		}
3608	}
3609	usb_unlock_device(udev);
3610	return status;
3611}
3612
3613/* Returns 1 if there was a remote wakeup and a connect status change. */
3614static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
3615		u16 portstatus, u16 portchange)
3616		__must_hold(&port_dev->status_lock)
3617{
3618	struct usb_port *port_dev = hub->ports[port - 1];
3619	struct usb_device *hdev;
3620	struct usb_device *udev;
3621	int connect_change = 0;
3622	u16 link_state;
3623	int ret;
3624
3625	hdev = hub->hdev;
3626	udev = port_dev->child;
3627	if (!hub_is_superspeed(hdev)) {
3628		if (!(portchange & USB_PORT_STAT_C_SUSPEND))
3629			return 0;
3630		usb_clear_port_feature(hdev, port, USB_PORT_FEAT_C_SUSPEND);
3631	} else {
3632		link_state = portstatus & USB_PORT_STAT_LINK_STATE;
3633		if (!udev || udev->state != USB_STATE_SUSPENDED ||
3634				(link_state != USB_SS_PORT_LS_U0 &&
3635				 link_state != USB_SS_PORT_LS_U1 &&
3636				 link_state != USB_SS_PORT_LS_U2))
3637			return 0;
3638	}
3639
3640	if (udev) {
3641		/* TRSMRCY = 10 msec */
3642		msleep(10);
3643
3644		usb_unlock_port(port_dev);
3645		ret = usb_remote_wakeup(udev);
3646		usb_lock_port(port_dev);
3647		if (ret < 0)
3648			connect_change = 1;
3649	} else {
3650		ret = -ENODEV;
3651		hub_port_disable(hub, port, 1);
3652	}
3653	dev_dbg(&port_dev->dev, "resume, status %d\n", ret);
3654	return connect_change;
3655}
3656
3657static int check_ports_changed(struct usb_hub *hub)
3658{
3659	int port1;
3660
3661	for (port1 = 1; port1 <= hub->hdev->maxchild; ++port1) {
3662		u16 portstatus, portchange;
3663		int status;
3664
3665		status = hub_port_status(hub, port1, &portstatus, &portchange);
3666		if (!status && portchange)
3667			return 1;
3668	}
3669	return 0;
3670}
3671
3672static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
3673{
3674	struct usb_hub		*hub = usb_get_intfdata(intf);
3675	struct usb_device	*hdev = hub->hdev;
3676	unsigned		port1;
 
3677
3678	/*
3679	 * Warn if children aren't already suspended.
3680	 * Also, add up the number of wakeup-enabled descendants.
3681	 */
3682	hub->wakeup_enabled_descendants = 0;
3683	for (port1 = 1; port1 <= hdev->maxchild; port1++) {
3684		struct usb_port *port_dev = hub->ports[port1 - 1];
3685		struct usb_device *udev = port_dev->child;
3686
3687		if (udev && udev->can_submit) {
3688			dev_warn(&port_dev->dev, "device %s not suspended yet\n",
3689					dev_name(&udev->dev));
3690			if (PMSG_IS_AUTO(msg))
3691				return -EBUSY;
3692		}
3693		if (udev)
3694			hub->wakeup_enabled_descendants +=
3695					usb_wakeup_enabled_descendants(udev);
3696	}
3697
3698	if (hdev->do_remote_wakeup && hub->quirk_check_port_auto_suspend) {
3699		/* check if there are changes pending on hub ports */
3700		if (check_ports_changed(hub)) {
3701			if (PMSG_IS_AUTO(msg))
3702				return -EBUSY;
3703			pm_wakeup_event(&hdev->dev, 2000);
3704		}
3705	}
3706
3707	if (hub_is_superspeed(hdev) && hdev->do_remote_wakeup) {
3708		/* Enable hub to send remote wakeup for all ports. */
3709		for (port1 = 1; port1 <= hdev->maxchild; port1++) {
3710			set_port_feature(hdev,
3711					 port1 |
3712					 USB_PORT_FEAT_REMOTE_WAKE_CONNECT |
3713					 USB_PORT_FEAT_REMOTE_WAKE_DISCONNECT |
3714					 USB_PORT_FEAT_REMOTE_WAKE_OVER_CURRENT,
3715					 USB_PORT_FEAT_REMOTE_WAKE_MASK);
3716		}
3717	}
3718
3719	dev_dbg(&intf->dev, "%s\n", __func__);
3720
3721	/* stop hub_wq and related activity */
3722	hub_quiesce(hub, HUB_SUSPEND);
3723	return 0;
3724}
3725
3726/* Report wakeup requests from the ports of a resuming root hub */
3727static void report_wakeup_requests(struct usb_hub *hub)
3728{
3729	struct usb_device	*hdev = hub->hdev;
3730	struct usb_device	*udev;
3731	struct usb_hcd		*hcd;
3732	unsigned long		resuming_ports;
3733	int			i;
3734
3735	if (hdev->parent)
3736		return;		/* Not a root hub */
3737
3738	hcd = bus_to_hcd(hdev->bus);
3739	if (hcd->driver->get_resuming_ports) {
3740
3741		/*
3742		 * The get_resuming_ports() method returns a bitmap (origin 0)
3743		 * of ports which have started wakeup signaling but have not
3744		 * yet finished resuming.  During system resume we will
3745		 * resume all the enabled ports, regardless of any wakeup
3746		 * signals, which means the wakeup requests would be lost.
3747		 * To prevent this, report them to the PM core here.
3748		 */
3749		resuming_ports = hcd->driver->get_resuming_ports(hcd);
3750		for (i = 0; i < hdev->maxchild; ++i) {
3751			if (test_bit(i, &resuming_ports)) {
3752				udev = hub->ports[i]->child;
3753				if (udev)
3754					pm_wakeup_event(&udev->dev, 0);
3755			}
3756		}
3757	}
3758}
3759
3760static int hub_resume(struct usb_interface *intf)
3761{
3762	struct usb_hub *hub = usb_get_intfdata(intf);
3763
3764	dev_dbg(&intf->dev, "%s\n", __func__);
3765	hub_activate(hub, HUB_RESUME);
3766
3767	/*
3768	 * This should be called only for system resume, not runtime resume.
3769	 * We can't tell the difference here, so some wakeup requests will be
3770	 * reported at the wrong time or more than once.  This shouldn't
3771	 * matter much, so long as they do get reported.
3772	 */
3773	report_wakeup_requests(hub);
3774	return 0;
3775}
3776
3777static int hub_reset_resume(struct usb_interface *intf)
3778{
3779	struct usb_hub *hub = usb_get_intfdata(intf);
3780
3781	dev_dbg(&intf->dev, "%s\n", __func__);
3782	hub_activate(hub, HUB_RESET_RESUME);
3783	return 0;
3784}
3785
3786/**
3787 * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
3788 * @rhdev: struct usb_device for the root hub
3789 *
3790 * The USB host controller driver calls this function when its root hub
3791 * is resumed and Vbus power has been interrupted or the controller
3792 * has been reset.  The routine marks @rhdev as having lost power.
3793 * When the hub driver is resumed it will take notice and carry out
3794 * power-session recovery for all the "USB-PERSIST"-enabled child devices;
3795 * the others will be disconnected.
3796 */
3797void usb_root_hub_lost_power(struct usb_device *rhdev)
3798{
3799	dev_notice(&rhdev->dev, "root hub lost power or was reset\n");
3800	rhdev->reset_resume = 1;
3801}
3802EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
3803
3804static const char * const usb3_lpm_names[]  = {
3805	"U0",
3806	"U1",
3807	"U2",
3808	"U3",
3809};
3810
3811/*
3812 * Send a Set SEL control transfer to the device, prior to enabling
3813 * device-initiated U1 or U2.  This lets the device know the exit latencies from
3814 * the time the device initiates a U1 or U2 exit, to the time it will receive a
3815 * packet from the host.
3816 *
3817 * This function will fail if the SEL or PEL values for udev are greater than
3818 * the maximum allowed values for the link state to be enabled.
3819 */
3820static int usb_req_set_sel(struct usb_device *udev, enum usb3_link_state state)
3821{
3822	struct usb_set_sel_req *sel_values;
3823	unsigned long long u1_sel;
3824	unsigned long long u1_pel;
3825	unsigned long long u2_sel;
3826	unsigned long long u2_pel;
3827	int ret;
3828
3829	if (udev->state != USB_STATE_CONFIGURED)
3830		return 0;
3831
3832	/* Convert SEL and PEL stored in ns to us */
3833	u1_sel = DIV_ROUND_UP(udev->u1_params.sel, 1000);
3834	u1_pel = DIV_ROUND_UP(udev->u1_params.pel, 1000);
3835	u2_sel = DIV_ROUND_UP(udev->u2_params.sel, 1000);
3836	u2_pel = DIV_ROUND_UP(udev->u2_params.pel, 1000);
3837
3838	/*
3839	 * Make sure that the calculated SEL and PEL values for the link
3840	 * state we're enabling aren't bigger than the max SEL/PEL
3841	 * value that will fit in the SET SEL control transfer.
3842	 * Otherwise the device would get an incorrect idea of the exit
3843	 * latency for the link state, and could start a device-initiated
3844	 * U1/U2 when the exit latencies are too high.
3845	 */
3846	if ((state == USB3_LPM_U1 &&
3847				(u1_sel > USB3_LPM_MAX_U1_SEL_PEL ||
3848				 u1_pel > USB3_LPM_MAX_U1_SEL_PEL)) ||
3849			(state == USB3_LPM_U2 &&
3850			 (u2_sel > USB3_LPM_MAX_U2_SEL_PEL ||
3851			  u2_pel > USB3_LPM_MAX_U2_SEL_PEL))) {
3852		dev_dbg(&udev->dev, "Device-initiated %s disabled due to long SEL %llu us or PEL %llu us\n",
3853				usb3_lpm_names[state], u1_sel, u1_pel);
3854		return -EINVAL;
3855	}
3856
3857	/*
3858	 * If we're enabling device-initiated LPM for one link state,
3859	 * but the other link state has a too high SEL or PEL value,
3860	 * just set those values to the max in the Set SEL request.
3861	 */
3862	if (u1_sel > USB3_LPM_MAX_U1_SEL_PEL)
3863		u1_sel = USB3_LPM_MAX_U1_SEL_PEL;
3864
3865	if (u1_pel > USB3_LPM_MAX_U1_SEL_PEL)
3866		u1_pel = USB3_LPM_MAX_U1_SEL_PEL;
3867
3868	if (u2_sel > USB3_LPM_MAX_U2_SEL_PEL)
3869		u2_sel = USB3_LPM_MAX_U2_SEL_PEL;
3870
3871	if (u2_pel > USB3_LPM_MAX_U2_SEL_PEL)
3872		u2_pel = USB3_LPM_MAX_U2_SEL_PEL;
3873
3874	/*
3875	 * usb_enable_lpm() can be called as part of a failed device reset,
3876	 * which may be initiated by an error path of a mass storage driver.
3877	 * Therefore, use GFP_NOIO.
3878	 */
3879	sel_values = kmalloc(sizeof *(sel_values), GFP_NOIO);
3880	if (!sel_values)
3881		return -ENOMEM;
3882
3883	sel_values->u1_sel = u1_sel;
3884	sel_values->u1_pel = u1_pel;
3885	sel_values->u2_sel = cpu_to_le16(u2_sel);
3886	sel_values->u2_pel = cpu_to_le16(u2_pel);
3887
3888	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3889			USB_REQ_SET_SEL,
3890			USB_RECIP_DEVICE,
3891			0, 0,
3892			sel_values, sizeof *(sel_values),
3893			USB_CTRL_SET_TIMEOUT);
3894	kfree(sel_values);
3895	return ret;
3896}
3897
3898/*
3899 * Enable or disable device-initiated U1 or U2 transitions.
3900 */
3901static int usb_set_device_initiated_lpm(struct usb_device *udev,
3902		enum usb3_link_state state, bool enable)
3903{
3904	int ret;
3905	int feature;
3906
3907	switch (state) {
3908	case USB3_LPM_U1:
3909		feature = USB_DEVICE_U1_ENABLE;
3910		break;
3911	case USB3_LPM_U2:
3912		feature = USB_DEVICE_U2_ENABLE;
3913		break;
3914	default:
3915		dev_warn(&udev->dev, "%s: Can't %s non-U1 or U2 state.\n",
3916				__func__, enable ? "enable" : "disable");
3917		return -EINVAL;
3918	}
3919
3920	if (udev->state != USB_STATE_CONFIGURED) {
3921		dev_dbg(&udev->dev, "%s: Can't %s %s state "
3922				"for unconfigured device.\n",
3923				__func__, enable ? "enable" : "disable",
3924				usb3_lpm_names[state]);
3925		return 0;
3926	}
3927
3928	if (enable) {
3929		/*
3930		 * Now send the control transfer to enable device-initiated LPM
3931		 * for either U1 or U2.
3932		 */
3933		ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3934				USB_REQ_SET_FEATURE,
3935				USB_RECIP_DEVICE,
3936				feature,
3937				0, NULL, 0,
3938				USB_CTRL_SET_TIMEOUT);
3939	} else {
3940		ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3941				USB_REQ_CLEAR_FEATURE,
3942				USB_RECIP_DEVICE,
3943				feature,
3944				0, NULL, 0,
3945				USB_CTRL_SET_TIMEOUT);
3946	}
3947	if (ret < 0) {
3948		dev_warn(&udev->dev, "%s of device-initiated %s failed.\n",
3949				enable ? "Enable" : "Disable",
3950				usb3_lpm_names[state]);
3951		return -EBUSY;
3952	}
3953	return 0;
3954}
3955
3956static int usb_set_lpm_timeout(struct usb_device *udev,
3957		enum usb3_link_state state, int timeout)
3958{
3959	int ret;
3960	int feature;
3961
3962	switch (state) {
3963	case USB3_LPM_U1:
3964		feature = USB_PORT_FEAT_U1_TIMEOUT;
3965		break;
3966	case USB3_LPM_U2:
3967		feature = USB_PORT_FEAT_U2_TIMEOUT;
3968		break;
3969	default:
3970		dev_warn(&udev->dev, "%s: Can't set timeout for non-U1 or U2 state.\n",
3971				__func__);
3972		return -EINVAL;
3973	}
3974
3975	if (state == USB3_LPM_U1 && timeout > USB3_LPM_U1_MAX_TIMEOUT &&
3976			timeout != USB3_LPM_DEVICE_INITIATED) {
3977		dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x, "
3978				"which is a reserved value.\n",
3979				usb3_lpm_names[state], timeout);
3980		return -EINVAL;
3981	}
3982
3983	ret = set_port_feature(udev->parent,
3984			USB_PORT_LPM_TIMEOUT(timeout) | udev->portnum,
3985			feature);
3986	if (ret < 0) {
3987		dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x,"
3988				"error code %i\n", usb3_lpm_names[state],
3989				timeout, ret);
3990		return -EBUSY;
3991	}
3992	if (state == USB3_LPM_U1)
3993		udev->u1_params.timeout = timeout;
3994	else
3995		udev->u2_params.timeout = timeout;
3996	return 0;
3997}
3998
3999/*
4000 * Enable the hub-initiated U1/U2 idle timeouts, and enable device-initiated
4001 * U1/U2 entry.
4002 *
4003 * We will attempt to enable U1 or U2, but there are no guarantees that the
4004 * control transfers to set the hub timeout or enable device-initiated U1/U2
4005 * will be successful.
4006 *
4007 * If the control transfer to enable device-initiated U1/U2 entry fails, then
4008 * hub-initiated U1/U2 will be disabled.
4009 *
4010 * If we cannot set the parent hub U1/U2 timeout, we attempt to let the xHCI
4011 * driver know about it.  If that call fails, it should be harmless, and just
4012 * take up more slightly more bus bandwidth for unnecessary U1/U2 exit latency.
4013 */
4014static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
4015		enum usb3_link_state state)
4016{
4017	int timeout, ret;
4018	__u8 u1_mel = udev->bos->ss_cap->bU1devExitLat;
4019	__le16 u2_mel = udev->bos->ss_cap->bU2DevExitLat;
4020
4021	/* If the device says it doesn't have *any* exit latency to come out of
4022	 * U1 or U2, it's probably lying.  Assume it doesn't implement that link
4023	 * state.
4024	 */
4025	if ((state == USB3_LPM_U1 && u1_mel == 0) ||
4026			(state == USB3_LPM_U2 && u2_mel == 0))
4027		return;
4028
4029	/*
4030	 * First, let the device know about the exit latencies
4031	 * associated with the link state we're about to enable.
4032	 */
4033	ret = usb_req_set_sel(udev, state);
4034	if (ret < 0) {
4035		dev_warn(&udev->dev, "Set SEL for device-initiated %s failed.\n",
4036				usb3_lpm_names[state]);
4037		return;
4038	}
4039
4040	/* We allow the host controller to set the U1/U2 timeout internally
4041	 * first, so that it can change its schedule to account for the
4042	 * additional latency to send data to a device in a lower power
4043	 * link state.
4044	 */
4045	timeout = hcd->driver->enable_usb3_lpm_timeout(hcd, udev, state);
4046
4047	/* xHCI host controller doesn't want to enable this LPM state. */
4048	if (timeout == 0)
4049		return;
4050
4051	if (timeout < 0) {
4052		dev_warn(&udev->dev, "Could not enable %s link state, "
4053				"xHCI error %i.\n", usb3_lpm_names[state],
4054				timeout);
4055		return;
4056	}
4057
4058	if (usb_set_lpm_timeout(udev, state, timeout)) {
4059		/* If we can't set the parent hub U1/U2 timeout,
4060		 * device-initiated LPM won't be allowed either, so let the xHCI
4061		 * host know that this link state won't be enabled.
4062		 */
4063		hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
4064		return;
4065	}
 
 
 
 
4066
4067	/* Only a configured device will accept the Set Feature
4068	 * U1/U2_ENABLE
4069	 */
4070	if (udev->actconfig &&
4071	    usb_set_device_initiated_lpm(udev, state, true) == 0) {
 
4072		if (state == USB3_LPM_U1)
4073			udev->usb3_lpm_u1_enabled = 1;
4074		else if (state == USB3_LPM_U2)
4075			udev->usb3_lpm_u2_enabled = 1;
4076	} else {
4077		/* Don't request U1/U2 entry if the device
4078		 * cannot transition to U1/U2.
4079		 */
4080		usb_set_lpm_timeout(udev, state, 0);
4081		hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
4082	}
4083}
4084
4085/*
4086 * Disable the hub-initiated U1/U2 idle timeouts, and disable device-initiated
4087 * U1/U2 entry.
4088 *
4089 * If this function returns -EBUSY, the parent hub will still allow U1/U2 entry.
4090 * If zero is returned, the parent will not allow the link to go into U1/U2.
4091 *
4092 * If zero is returned, device-initiated U1/U2 entry may still be enabled, but
4093 * it won't have an effect on the bus link state because the parent hub will
4094 * still disallow device-initiated U1/U2 entry.
4095 *
4096 * If zero is returned, the xHCI host controller may still think U1/U2 entry is
4097 * possible.  The result will be slightly more bus bandwidth will be taken up
4098 * (to account for U1/U2 exit latency), but it should be harmless.
4099 */
4100static int usb_disable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
4101		enum usb3_link_state state)
4102{
4103	switch (state) {
4104	case USB3_LPM_U1:
4105	case USB3_LPM_U2:
4106		break;
4107	default:
4108		dev_warn(&udev->dev, "%s: Can't disable non-U1 or U2 state.\n",
4109				__func__);
4110		return -EINVAL;
4111	}
4112
4113	if (usb_set_lpm_timeout(udev, state, 0))
4114		return -EBUSY;
4115
4116	usb_set_device_initiated_lpm(udev, state, false);
4117
4118	if (hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state))
4119		dev_warn(&udev->dev, "Could not disable xHCI %s timeout, "
4120				"bus schedule bandwidth may be impacted.\n",
4121				usb3_lpm_names[state]);
4122
4123	/* As soon as usb_set_lpm_timeout(0) return 0, hub initiated LPM
4124	 * is disabled. Hub will disallows link to enter U1/U2 as well,
4125	 * even device is initiating LPM. Hence LPM is disabled if hub LPM
4126	 * timeout set to 0, no matter device-initiated LPM is disabled or
4127	 * not.
4128	 */
4129	if (state == USB3_LPM_U1)
4130		udev->usb3_lpm_u1_enabled = 0;
4131	else if (state == USB3_LPM_U2)
4132		udev->usb3_lpm_u2_enabled = 0;
4133
4134	return 0;
4135}
4136
4137/*
4138 * Disable hub-initiated and device-initiated U1 and U2 entry.
4139 * Caller must own the bandwidth_mutex.
4140 *
4141 * This will call usb_enable_lpm() on failure, which will decrement
4142 * lpm_disable_count, and will re-enable LPM if lpm_disable_count reaches zero.
4143 */
4144int usb_disable_lpm(struct usb_device *udev)
4145{
4146	struct usb_hcd *hcd;
4147
4148	if (!udev || !udev->parent ||
4149			udev->speed < USB_SPEED_SUPER ||
4150			!udev->lpm_capable ||
4151			udev->state < USB_STATE_CONFIGURED)
4152		return 0;
4153
4154	hcd = bus_to_hcd(udev->bus);
4155	if (!hcd || !hcd->driver->disable_usb3_lpm_timeout)
4156		return 0;
4157
4158	udev->lpm_disable_count++;
4159	if ((udev->u1_params.timeout == 0 && udev->u2_params.timeout == 0))
4160		return 0;
4161
4162	/* If LPM is enabled, attempt to disable it. */
4163	if (usb_disable_link_state(hcd, udev, USB3_LPM_U1))
4164		goto enable_lpm;
4165	if (usb_disable_link_state(hcd, udev, USB3_LPM_U2))
4166		goto enable_lpm;
4167
4168	return 0;
4169
4170enable_lpm:
4171	usb_enable_lpm(udev);
4172	return -EBUSY;
4173}
4174EXPORT_SYMBOL_GPL(usb_disable_lpm);
4175
4176/* Grab the bandwidth_mutex before calling usb_disable_lpm() */
4177int usb_unlocked_disable_lpm(struct usb_device *udev)
4178{
4179	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4180	int ret;
4181
4182	if (!hcd)
4183		return -EINVAL;
4184
4185	mutex_lock(hcd->bandwidth_mutex);
4186	ret = usb_disable_lpm(udev);
4187	mutex_unlock(hcd->bandwidth_mutex);
4188
4189	return ret;
4190}
4191EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
4192
4193/*
4194 * Attempt to enable device-initiated and hub-initiated U1 and U2 entry.  The
4195 * xHCI host policy may prevent U1 or U2 from being enabled.
4196 *
4197 * Other callers may have disabled link PM, so U1 and U2 entry will be disabled
4198 * until the lpm_disable_count drops to zero.  Caller must own the
4199 * bandwidth_mutex.
4200 */
4201void usb_enable_lpm(struct usb_device *udev)
4202{
4203	struct usb_hcd *hcd;
4204	struct usb_hub *hub;
4205	struct usb_port *port_dev;
4206
4207	if (!udev || !udev->parent ||
4208			udev->speed < USB_SPEED_SUPER ||
4209			!udev->lpm_capable ||
4210			udev->state < USB_STATE_CONFIGURED)
4211		return;
4212
4213	udev->lpm_disable_count--;
4214	hcd = bus_to_hcd(udev->bus);
4215	/* Double check that we can both enable and disable LPM.
4216	 * Device must be configured to accept set feature U1/U2 timeout.
4217	 */
4218	if (!hcd || !hcd->driver->enable_usb3_lpm_timeout ||
4219			!hcd->driver->disable_usb3_lpm_timeout)
4220		return;
4221
4222	if (udev->lpm_disable_count > 0)
4223		return;
4224
4225	hub = usb_hub_to_struct_hub(udev->parent);
4226	if (!hub)
4227		return;
4228
4229	port_dev = hub->ports[udev->portnum - 1];
4230
4231	if (port_dev->usb3_lpm_u1_permit)
4232		usb_enable_link_state(hcd, udev, USB3_LPM_U1);
4233
4234	if (port_dev->usb3_lpm_u2_permit)
4235		usb_enable_link_state(hcd, udev, USB3_LPM_U2);
4236}
4237EXPORT_SYMBOL_GPL(usb_enable_lpm);
4238
4239/* Grab the bandwidth_mutex before calling usb_enable_lpm() */
4240void usb_unlocked_enable_lpm(struct usb_device *udev)
4241{
4242	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4243
4244	if (!hcd)
4245		return;
4246
4247	mutex_lock(hcd->bandwidth_mutex);
4248	usb_enable_lpm(udev);
4249	mutex_unlock(hcd->bandwidth_mutex);
4250}
4251EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
4252
4253/* usb3 devices use U3 for disabled, make sure remote wakeup is disabled */
4254static void hub_usb3_port_prepare_disable(struct usb_hub *hub,
4255					  struct usb_port *port_dev)
4256{
4257	struct usb_device *udev = port_dev->child;
4258	int ret;
4259
4260	if (udev && udev->port_is_suspended && udev->do_remote_wakeup) {
4261		ret = hub_set_port_link_state(hub, port_dev->portnum,
4262					      USB_SS_PORT_LS_U0);
4263		if (!ret) {
4264			msleep(USB_RESUME_TIMEOUT);
4265			ret = usb_disable_remote_wakeup(udev);
4266		}
4267		if (ret)
4268			dev_warn(&udev->dev,
4269				 "Port disable: can't disable remote wake\n");
4270		udev->do_remote_wakeup = 0;
4271	}
4272}
4273
4274#else	/* CONFIG_PM */
4275
4276#define hub_suspend		NULL
4277#define hub_resume		NULL
4278#define hub_reset_resume	NULL
4279
4280static inline void hub_usb3_port_prepare_disable(struct usb_hub *hub,
4281						 struct usb_port *port_dev) { }
4282
4283int usb_disable_lpm(struct usb_device *udev)
4284{
4285	return 0;
4286}
4287EXPORT_SYMBOL_GPL(usb_disable_lpm);
4288
4289void usb_enable_lpm(struct usb_device *udev) { }
4290EXPORT_SYMBOL_GPL(usb_enable_lpm);
4291
4292int usb_unlocked_disable_lpm(struct usb_device *udev)
4293{
4294	return 0;
4295}
4296EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
4297
4298void usb_unlocked_enable_lpm(struct usb_device *udev) { }
4299EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
4300
4301int usb_disable_ltm(struct usb_device *udev)
4302{
4303	return 0;
4304}
4305EXPORT_SYMBOL_GPL(usb_disable_ltm);
4306
4307void usb_enable_ltm(struct usb_device *udev) { }
4308EXPORT_SYMBOL_GPL(usb_enable_ltm);
4309
4310static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
4311		u16 portstatus, u16 portchange)
4312{
4313	return 0;
4314}
4315
4316#endif	/* CONFIG_PM */
4317
4318/*
4319 * USB-3 does not have a similar link state as USB-2 that will avoid negotiating
4320 * a connection with a plugged-in cable but will signal the host when the cable
4321 * is unplugged. Disable remote wake and set link state to U3 for USB-3 devices
4322 */
4323static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
4324{
4325	struct usb_port *port_dev = hub->ports[port1 - 1];
4326	struct usb_device *hdev = hub->hdev;
4327	int ret = 0;
4328
4329	if (!hub->error) {
4330		if (hub_is_superspeed(hub->hdev)) {
4331			hub_usb3_port_prepare_disable(hub, port_dev);
4332			ret = hub_set_port_link_state(hub, port_dev->portnum,
4333						      USB_SS_PORT_LS_U3);
4334		} else {
4335			ret = usb_clear_port_feature(hdev, port1,
4336					USB_PORT_FEAT_ENABLE);
4337		}
4338	}
4339	if (port_dev->child && set_state)
4340		usb_set_device_state(port_dev->child, USB_STATE_NOTATTACHED);
4341	if (ret && ret != -ENODEV)
4342		dev_err(&port_dev->dev, "cannot disable (err = %d)\n", ret);
4343	return ret;
4344}
4345
4346/*
4347 * usb_port_disable - disable a usb device's upstream port
4348 * @udev: device to disable
4349 * Context: @udev locked, must be able to sleep.
4350 *
4351 * Disables a USB device that isn't in active use.
4352 */
4353int usb_port_disable(struct usb_device *udev)
4354{
4355	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
4356
4357	return hub_port_disable(hub, udev->portnum, 0);
4358}
4359
4360/* USB 2.0 spec, 7.1.7.3 / fig 7-29:
4361 *
4362 * Between connect detection and reset signaling there must be a delay
4363 * of 100ms at least for debounce and power-settling.  The corresponding
4364 * timer shall restart whenever the downstream port detects a disconnect.
4365 *
4366 * Apparently there are some bluetooth and irda-dongles and a number of
4367 * low-speed devices for which this debounce period may last over a second.
4368 * Not covered by the spec - but easy to deal with.
4369 *
4370 * This implementation uses a 1500ms total debounce timeout; if the
4371 * connection isn't stable by then it returns -ETIMEDOUT.  It checks
4372 * every 25ms for transient disconnects.  When the port status has been
4373 * unchanged for 100ms it returns the port status.
4374 */
4375int hub_port_debounce(struct usb_hub *hub, int port1, bool must_be_connected)
4376{
4377	int ret;
4378	u16 portchange, portstatus;
4379	unsigned connection = 0xffff;
4380	int total_time, stable_time = 0;
4381	struct usb_port *port_dev = hub->ports[port1 - 1];
4382
4383	for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
4384		ret = hub_port_status(hub, port1, &portstatus, &portchange);
4385		if (ret < 0)
4386			return ret;
4387
4388		if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
4389		     (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
4390			if (!must_be_connected ||
4391			     (connection == USB_PORT_STAT_CONNECTION))
4392				stable_time += HUB_DEBOUNCE_STEP;
4393			if (stable_time >= HUB_DEBOUNCE_STABLE)
4394				break;
4395		} else {
4396			stable_time = 0;
4397			connection = portstatus & USB_PORT_STAT_CONNECTION;
4398		}
4399
4400		if (portchange & USB_PORT_STAT_C_CONNECTION) {
4401			usb_clear_port_feature(hub->hdev, port1,
4402					USB_PORT_FEAT_C_CONNECTION);
4403		}
4404
4405		if (total_time >= HUB_DEBOUNCE_TIMEOUT)
4406			break;
4407		msleep(HUB_DEBOUNCE_STEP);
4408	}
4409
4410	dev_dbg(&port_dev->dev, "debounce total %dms stable %dms status 0x%x\n",
4411			total_time, stable_time, portstatus);
4412
4413	if (stable_time < HUB_DEBOUNCE_STABLE)
4414		return -ETIMEDOUT;
4415	return portstatus;
4416}
4417
4418void usb_ep0_reinit(struct usb_device *udev)
4419{
4420	usb_disable_endpoint(udev, 0 + USB_DIR_IN, true);
4421	usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true);
4422	usb_enable_endpoint(udev, &udev->ep0, true);
4423}
4424EXPORT_SYMBOL_GPL(usb_ep0_reinit);
4425
4426#define usb_sndaddr0pipe()	(PIPE_CONTROL << 30)
4427#define usb_rcvaddr0pipe()	((PIPE_CONTROL << 30) | USB_DIR_IN)
4428
4429static int hub_set_address(struct usb_device *udev, int devnum)
4430{
4431	int retval;
4432	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4433
4434	/*
4435	 * The host controller will choose the device address,
4436	 * instead of the core having chosen it earlier
4437	 */
4438	if (!hcd->driver->address_device && devnum <= 1)
4439		return -EINVAL;
4440	if (udev->state == USB_STATE_ADDRESS)
4441		return 0;
4442	if (udev->state != USB_STATE_DEFAULT)
4443		return -EINVAL;
4444	if (hcd->driver->address_device)
4445		retval = hcd->driver->address_device(hcd, udev);
4446	else
4447		retval = usb_control_msg(udev, usb_sndaddr0pipe(),
4448				USB_REQ_SET_ADDRESS, 0, devnum, 0,
4449				NULL, 0, USB_CTRL_SET_TIMEOUT);
4450	if (retval == 0) {
4451		update_devnum(udev, devnum);
4452		/* Device now using proper address. */
4453		usb_set_device_state(udev, USB_STATE_ADDRESS);
4454		usb_ep0_reinit(udev);
4455	}
4456	return retval;
4457}
4458
4459/*
4460 * There are reports of USB 3.0 devices that say they support USB 2.0 Link PM
4461 * when they're plugged into a USB 2.0 port, but they don't work when LPM is
4462 * enabled.
4463 *
4464 * Only enable USB 2.0 Link PM if the port is internal (hardwired), or the
4465 * device says it supports the new USB 2.0 Link PM errata by setting the BESL
4466 * support bit in the BOS descriptor.
4467 */
4468static void hub_set_initial_usb2_lpm_policy(struct usb_device *udev)
4469{
4470	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
4471	int connect_type = USB_PORT_CONNECT_TYPE_UNKNOWN;
4472
4473	if (!udev->usb2_hw_lpm_capable || !udev->bos)
4474		return;
4475
4476	if (hub)
4477		connect_type = hub->ports[udev->portnum - 1]->connect_type;
4478
4479	if ((udev->bos->ext_cap->bmAttributes & cpu_to_le32(USB_BESL_SUPPORT)) ||
4480			connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
4481		udev->usb2_hw_lpm_allowed = 1;
4482		usb_enable_usb2_hardware_lpm(udev);
4483	}
4484}
4485
4486static int hub_enable_device(struct usb_device *udev)
4487{
4488	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4489
4490	if (!hcd->driver->enable_device)
4491		return 0;
4492	if (udev->state == USB_STATE_ADDRESS)
4493		return 0;
4494	if (udev->state != USB_STATE_DEFAULT)
4495		return -EINVAL;
4496
4497	return hcd->driver->enable_device(hcd, udev);
4498}
4499
4500/* Reset device, (re)assign address, get device descriptor.
4501 * Device connection must be stable, no more debouncing needed.
4502 * Returns device in USB_STATE_ADDRESS, except on error.
4503 *
4504 * If this is called for an already-existing device (as part of
4505 * usb_reset_and_verify_device), the caller must own the device lock and
4506 * the port lock.  For a newly detected device that is not accessible
4507 * through any global pointers, it's not necessary to lock the device,
4508 * but it is still necessary to lock the port.
4509 */
4510static int
4511hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1,
4512		int retry_counter)
4513{
4514	struct usb_device	*hdev = hub->hdev;
4515	struct usb_hcd		*hcd = bus_to_hcd(hdev->bus);
4516	struct usb_port		*port_dev = hub->ports[port1 - 1];
4517	int			retries, operations, retval, i;
4518	unsigned		delay = HUB_SHORT_RESET_TIME;
4519	enum usb_device_speed	oldspeed = udev->speed;
4520	const char		*speed;
4521	int			devnum = udev->devnum;
4522	const char		*driver_name;
4523
4524	/* root hub ports have a slightly longer reset period
4525	 * (from USB 2.0 spec, section 7.1.7.5)
4526	 */
4527	if (!hdev->parent) {
4528		delay = HUB_ROOT_RESET_TIME;
4529		if (port1 == hdev->bus->otg_port)
4530			hdev->bus->b_hnp_enable = 0;
4531	}
4532
4533	/* Some low speed devices have problems with the quick delay, so */
4534	/*  be a bit pessimistic with those devices. RHbug #23670 */
4535	if (oldspeed == USB_SPEED_LOW)
4536		delay = HUB_LONG_RESET_TIME;
4537
4538	mutex_lock(hcd->address0_mutex);
4539
4540	/* Reset the device; full speed may morph to high speed */
4541	/* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */
4542	retval = hub_port_reset(hub, port1, udev, delay, false);
4543	if (retval < 0)		/* error or disconnect */
4544		goto fail;
4545	/* success, speed is known */
4546
4547	retval = -ENODEV;
4548
4549	/* Don't allow speed changes at reset, except usb 3.0 to faster */
4550	if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed &&
4551	    !(oldspeed == USB_SPEED_SUPER && udev->speed > oldspeed)) {
4552		dev_dbg(&udev->dev, "device reset changed speed!\n");
4553		goto fail;
4554	}
4555	oldspeed = udev->speed;
4556
4557	/* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
4558	 * it's fixed size except for full speed devices.
4559	 * For Wireless USB devices, ep0 max packet is always 512 (tho
4560	 * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
4561	 */
4562	switch (udev->speed) {
4563	case USB_SPEED_SUPER_PLUS:
4564	case USB_SPEED_SUPER:
4565	case USB_SPEED_WIRELESS:	/* fixed at 512 */
4566		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
4567		break;
4568	case USB_SPEED_HIGH:		/* fixed at 64 */
4569		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
4570		break;
4571	case USB_SPEED_FULL:		/* 8, 16, 32, or 64 */
4572		/* to determine the ep0 maxpacket size, try to read
4573		 * the device descriptor to get bMaxPacketSize0 and
4574		 * then correct our initial guess.
4575		 */
4576		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
4577		break;
4578	case USB_SPEED_LOW:		/* fixed at 8 */
4579		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(8);
4580		break;
4581	default:
4582		goto fail;
4583	}
4584
4585	if (udev->speed == USB_SPEED_WIRELESS)
4586		speed = "variable speed Wireless";
4587	else
4588		speed = usb_speed_string(udev->speed);
4589
4590	/*
4591	 * The controller driver may be NULL if the controller device
4592	 * is the middle device between platform device and roothub.
4593	 * This middle device may not need a device driver due to
4594	 * all hardware control can be at platform device driver, this
4595	 * platform device is usually a dual-role USB controller device.
4596	 */
4597	if (udev->bus->controller->driver)
4598		driver_name = udev->bus->controller->driver->name;
4599	else
4600		driver_name = udev->bus->sysdev->driver->name;
4601
4602	if (udev->speed < USB_SPEED_SUPER)
4603		dev_info(&udev->dev,
4604				"%s %s USB device number %d using %s\n",
4605				(udev->config) ? "reset" : "new", speed,
4606				devnum, driver_name);
4607
4608	/* Set up TT records, if needed  */
4609	if (hdev->tt) {
4610		udev->tt = hdev->tt;
4611		udev->ttport = hdev->ttport;
4612	} else if (udev->speed != USB_SPEED_HIGH
4613			&& hdev->speed == USB_SPEED_HIGH) {
4614		if (!hub->tt.hub) {
4615			dev_err(&udev->dev, "parent hub has no TT\n");
4616			retval = -EINVAL;
4617			goto fail;
4618		}
4619		udev->tt = &hub->tt;
4620		udev->ttport = port1;
4621	}
4622
4623	/* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
4624	 * Because device hardware and firmware is sometimes buggy in
4625	 * this area, and this is how Linux has done it for ages.
4626	 * Change it cautiously.
4627	 *
4628	 * NOTE:  If use_new_scheme() is true we will start by issuing
4629	 * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
4630	 * so it may help with some non-standards-compliant devices.
4631	 * Otherwise we start with SET_ADDRESS and then try to read the
4632	 * first 8 bytes of the device descriptor to get the ep0 maxpacket
4633	 * value.
4634	 */
4635	for (retries = 0; retries < GET_DESCRIPTOR_TRIES; (++retries, msleep(100))) {
4636		bool did_new_scheme = false;
4637
4638		if (use_new_scheme(udev, retry_counter, port_dev)) {
4639			struct usb_device_descriptor *buf;
4640			int r = 0;
4641
4642			did_new_scheme = true;
4643			retval = hub_enable_device(udev);
4644			if (retval < 0) {
4645				dev_err(&udev->dev,
4646					"hub failed to enable device, error %d\n",
4647					retval);
4648				goto fail;
4649			}
4650
4651#define GET_DESCRIPTOR_BUFSIZE	64
4652			buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
4653			if (!buf) {
4654				retval = -ENOMEM;
4655				continue;
4656			}
4657
4658			/* Retry on all errors; some devices are flakey.
4659			 * 255 is for WUSB devices, we actually need to use
4660			 * 512 (WUSB1.0[4.8.1]).
4661			 */
4662			for (operations = 0; operations < 3; ++operations) {
4663				buf->bMaxPacketSize0 = 0;
4664				r = usb_control_msg(udev, usb_rcvaddr0pipe(),
4665					USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
4666					USB_DT_DEVICE << 8, 0,
4667					buf, GET_DESCRIPTOR_BUFSIZE,
4668					initial_descriptor_timeout);
4669				switch (buf->bMaxPacketSize0) {
4670				case 8: case 16: case 32: case 64: case 255:
4671					if (buf->bDescriptorType ==
4672							USB_DT_DEVICE) {
4673						r = 0;
4674						break;
4675					}
4676					/* FALL THROUGH */
4677				default:
4678					if (r == 0)
4679						r = -EPROTO;
4680					break;
4681				}
4682				/*
4683				 * Some devices time out if they are powered on
4684				 * when already connected. They need a second
4685				 * reset. But only on the first attempt,
4686				 * lest we get into a time out/reset loop
4687				 */
4688				if (r == 0 || (r == -ETIMEDOUT &&
4689						retries == 0 &&
4690						udev->speed > USB_SPEED_FULL))
4691					break;
4692			}
4693			udev->descriptor.bMaxPacketSize0 =
4694					buf->bMaxPacketSize0;
4695			kfree(buf);
4696
4697			retval = hub_port_reset(hub, port1, udev, delay, false);
4698			if (retval < 0)		/* error or disconnect */
4699				goto fail;
4700			if (oldspeed != udev->speed) {
4701				dev_dbg(&udev->dev,
4702					"device reset changed speed!\n");
4703				retval = -ENODEV;
4704				goto fail;
4705			}
4706			if (r) {
4707				if (r != -ENODEV)
4708					dev_err(&udev->dev, "device descriptor read/64, error %d\n",
4709							r);
4710				retval = -EMSGSIZE;
4711				continue;
4712			}
4713#undef GET_DESCRIPTOR_BUFSIZE
4714		}
4715
4716		/*
4717		 * If device is WUSB, we already assigned an
4718		 * unauthorized address in the Connect Ack sequence;
4719		 * authorization will assign the final address.
4720		 */
4721		if (udev->wusb == 0) {
4722			for (operations = 0; operations < SET_ADDRESS_TRIES; ++operations) {
4723				retval = hub_set_address(udev, devnum);
4724				if (retval >= 0)
4725					break;
4726				msleep(200);
4727			}
4728			if (retval < 0) {
4729				if (retval != -ENODEV)
4730					dev_err(&udev->dev, "device not accepting address %d, error %d\n",
4731							devnum, retval);
4732				goto fail;
4733			}
4734			if (udev->speed >= USB_SPEED_SUPER) {
4735				devnum = udev->devnum;
4736				dev_info(&udev->dev,
4737						"%s SuperSpeed%s%s USB device number %d using %s\n",
4738						(udev->config) ? "reset" : "new",
4739					 (udev->speed == USB_SPEED_SUPER_PLUS) ?
4740							"Plus Gen 2" : " Gen 1",
4741					 (udev->rx_lanes == 2 && udev->tx_lanes == 2) ?
4742							"x2" : "",
4743					 devnum, driver_name);
4744			}
4745
4746			/* cope with hardware quirkiness:
4747			 *  - let SET_ADDRESS settle, some device hardware wants it
4748			 *  - read ep0 maxpacket even for high and low speed,
4749			 */
4750			msleep(10);
4751			/* use_new_scheme() checks the speed which may have
4752			 * changed since the initial look so we cache the result
4753			 * in did_new_scheme
4754			 */
4755			if (did_new_scheme)
4756				break;
4757		}
4758
4759		retval = usb_get_device_descriptor(udev, 8);
4760		if (retval < 8) {
4761			if (retval != -ENODEV)
4762				dev_err(&udev->dev,
4763					"device descriptor read/8, error %d\n",
4764					retval);
4765			if (retval >= 0)
4766				retval = -EMSGSIZE;
4767		} else {
4768			u32 delay;
4769
4770			retval = 0;
4771
4772			delay = udev->parent->hub_delay;
4773			udev->hub_delay = min_t(u32, delay,
4774						USB_TP_TRANSMISSION_DELAY_MAX);
4775			retval = usb_set_isoch_delay(udev);
4776			if (retval) {
4777				dev_dbg(&udev->dev,
4778					"Failed set isoch delay, error %d\n",
4779					retval);
4780				retval = 0;
4781			}
4782			break;
4783		}
4784	}
4785	if (retval)
4786		goto fail;
4787
4788	/*
4789	 * Some superspeed devices have finished the link training process
4790	 * and attached to a superspeed hub port, but the device descriptor
4791	 * got from those devices show they aren't superspeed devices. Warm
4792	 * reset the port attached by the devices can fix them.
4793	 */
4794	if ((udev->speed >= USB_SPEED_SUPER) &&
4795			(le16_to_cpu(udev->descriptor.bcdUSB) < 0x0300)) {
4796		dev_err(&udev->dev, "got a wrong device descriptor, "
4797				"warm reset device\n");
4798		hub_port_reset(hub, port1, udev,
4799				HUB_BH_RESET_TIME, true);
4800		retval = -EINVAL;
4801		goto fail;
4802	}
4803
4804	if (udev->descriptor.bMaxPacketSize0 == 0xff ||
4805			udev->speed >= USB_SPEED_SUPER)
4806		i = 512;
4807	else
4808		i = udev->descriptor.bMaxPacketSize0;
4809	if (usb_endpoint_maxp(&udev->ep0.desc) != i) {
4810		if (udev->speed == USB_SPEED_LOW ||
4811				!(i == 8 || i == 16 || i == 32 || i == 64)) {
4812			dev_err(&udev->dev, "Invalid ep0 maxpacket: %d\n", i);
4813			retval = -EMSGSIZE;
4814			goto fail;
4815		}
4816		if (udev->speed == USB_SPEED_FULL)
4817			dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
4818		else
4819			dev_warn(&udev->dev, "Using ep0 maxpacket: %d\n", i);
4820		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
4821		usb_ep0_reinit(udev);
4822	}
4823
4824	retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
4825	if (retval < (signed)sizeof(udev->descriptor)) {
4826		if (retval != -ENODEV)
4827			dev_err(&udev->dev, "device descriptor read/all, error %d\n",
4828					retval);
4829		if (retval >= 0)
4830			retval = -ENOMSG;
4831		goto fail;
4832	}
4833
4834	usb_detect_quirks(udev);
4835
4836	if (udev->wusb == 0 && le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0201) {
4837		retval = usb_get_bos_descriptor(udev);
4838		if (!retval) {
4839			udev->lpm_capable = usb_device_supports_lpm(udev);
4840			usb_set_lpm_parameters(udev);
4841		}
4842	}
4843
4844	retval = 0;
4845	/* notify HCD that we have a device connected and addressed */
4846	if (hcd->driver->update_device)
4847		hcd->driver->update_device(hcd, udev);
4848	hub_set_initial_usb2_lpm_policy(udev);
4849fail:
4850	if (retval) {
4851		hub_port_disable(hub, port1, 0);
4852		update_devnum(udev, devnum);	/* for disconnect processing */
4853	}
4854	mutex_unlock(hcd->address0_mutex);
4855	return retval;
4856}
4857
4858static void
4859check_highspeed(struct usb_hub *hub, struct usb_device *udev, int port1)
4860{
4861	struct usb_qualifier_descriptor	*qual;
4862	int				status;
4863
4864	if (udev->quirks & USB_QUIRK_DEVICE_QUALIFIER)
4865		return;
4866
4867	qual = kmalloc(sizeof *qual, GFP_KERNEL);
4868	if (qual == NULL)
4869		return;
4870
4871	status = usb_get_descriptor(udev, USB_DT_DEVICE_QUALIFIER, 0,
4872			qual, sizeof *qual);
4873	if (status == sizeof *qual) {
4874		dev_info(&udev->dev, "not running at top speed; "
4875			"connect to a high speed hub\n");
4876		/* hub LEDs are probably harder to miss than syslog */
4877		if (hub->has_indicators) {
4878			hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
4879			queue_delayed_work(system_power_efficient_wq,
4880					&hub->leds, 0);
4881		}
4882	}
4883	kfree(qual);
4884}
4885
4886static unsigned
4887hub_power_remaining(struct usb_hub *hub)
4888{
4889	struct usb_device *hdev = hub->hdev;
4890	int remaining;
4891	int port1;
4892
4893	if (!hub->limited_power)
4894		return 0;
4895
4896	remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
4897	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
4898		struct usb_port *port_dev = hub->ports[port1 - 1];
4899		struct usb_device *udev = port_dev->child;
4900		unsigned unit_load;
4901		int delta;
4902
4903		if (!udev)
4904			continue;
4905		if (hub_is_superspeed(udev))
4906			unit_load = 150;
4907		else
4908			unit_load = 100;
4909
4910		/*
4911		 * Unconfigured devices may not use more than one unit load,
4912		 * or 8mA for OTG ports
4913		 */
4914		if (udev->actconfig)
4915			delta = usb_get_max_power(udev, udev->actconfig);
4916		else if (port1 != udev->bus->otg_port || hdev->parent)
4917			delta = unit_load;
4918		else
4919			delta = 8;
4920		if (delta > hub->mA_per_port)
4921			dev_warn(&port_dev->dev, "%dmA is over %umA budget!\n",
4922					delta, hub->mA_per_port);
4923		remaining -= delta;
4924	}
4925	if (remaining < 0) {
4926		dev_warn(hub->intfdev, "%dmA over power budget!\n",
4927			-remaining);
4928		remaining = 0;
4929	}
4930	return remaining;
4931}
4932
4933static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
4934		u16 portchange)
4935{
4936	int status = -ENODEV;
4937	int i;
4938	unsigned unit_load;
4939	struct usb_device *hdev = hub->hdev;
4940	struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
4941	struct usb_port *port_dev = hub->ports[port1 - 1];
4942	struct usb_device *udev = port_dev->child;
4943	static int unreliable_port = -1;
4944
4945	/* Disconnect any existing devices under this port */
4946	if (udev) {
4947		if (hcd->usb_phy && !hdev->parent)
4948			usb_phy_notify_disconnect(hcd->usb_phy, udev->speed);
4949		usb_disconnect(&port_dev->child);
4950	}
4951
4952	/* We can forget about a "removed" device when there's a physical
4953	 * disconnect or the connect status changes.
4954	 */
4955	if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
4956			(portchange & USB_PORT_STAT_C_CONNECTION))
4957		clear_bit(port1, hub->removed_bits);
4958
4959	if (portchange & (USB_PORT_STAT_C_CONNECTION |
4960				USB_PORT_STAT_C_ENABLE)) {
4961		status = hub_port_debounce_be_stable(hub, port1);
4962		if (status < 0) {
4963			if (status != -ENODEV &&
4964				port1 != unreliable_port &&
4965				printk_ratelimit())
4966				dev_err(&port_dev->dev, "connect-debounce failed\n");
4967			portstatus &= ~USB_PORT_STAT_CONNECTION;
4968			unreliable_port = port1;
4969		} else {
4970			portstatus = status;
4971		}
4972	}
4973
4974	/* Return now if debouncing failed or nothing is connected or
4975	 * the device was "removed".
4976	 */
4977	if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
4978			test_bit(port1, hub->removed_bits)) {
4979
4980		/*
4981		 * maybe switch power back on (e.g. root hub was reset)
4982		 * but only if the port isn't owned by someone else.
4983		 */
4984		if (hub_is_port_power_switchable(hub)
4985				&& !port_is_power_on(hub, portstatus)
4986				&& !port_dev->port_owner)
4987			set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
4988
4989		if (portstatus & USB_PORT_STAT_ENABLE)
4990			goto done;
4991		return;
4992	}
4993	if (hub_is_superspeed(hub->hdev))
4994		unit_load = 150;
4995	else
4996		unit_load = 100;
4997
4998	status = 0;
4999	for (i = 0; i < SET_CONFIG_TRIES; i++) {
5000
5001		/* reallocate for each attempt, since references
5002		 * to the previous one can escape in various ways
5003		 */
5004		udev = usb_alloc_dev(hdev, hdev->bus, port1);
5005		if (!udev) {
5006			dev_err(&port_dev->dev,
5007					"couldn't allocate usb_device\n");
5008			goto done;
5009		}
5010
5011		usb_set_device_state(udev, USB_STATE_POWERED);
5012		udev->bus_mA = hub->mA_per_port;
5013		udev->level = hdev->level + 1;
5014		udev->wusb = hub_is_wusb(hub);
5015
5016		/* Devices connected to SuperSpeed hubs are USB 3.0 or later */
5017		if (hub_is_superspeed(hub->hdev))
5018			udev->speed = USB_SPEED_SUPER;
5019		else
5020			udev->speed = USB_SPEED_UNKNOWN;
5021
5022		choose_devnum(udev);
5023		if (udev->devnum <= 0) {
5024			status = -ENOTCONN;	/* Don't retry */
5025			goto loop;
5026		}
5027
5028		/* reset (non-USB 3.0 devices) and get descriptor */
5029		usb_lock_port(port_dev);
5030		status = hub_port_init(hub, udev, port1, i);
5031		usb_unlock_port(port_dev);
5032		if (status < 0)
5033			goto loop;
5034
5035		if (udev->quirks & USB_QUIRK_DELAY_INIT)
5036			msleep(2000);
5037
5038		/* consecutive bus-powered hubs aren't reliable; they can
5039		 * violate the voltage drop budget.  if the new child has
5040		 * a "powered" LED, users should notice we didn't enable it
5041		 * (without reading syslog), even without per-port LEDs
5042		 * on the parent.
5043		 */
5044		if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
5045				&& udev->bus_mA <= unit_load) {
5046			u16	devstat;
5047
5048			status = usb_get_std_status(udev, USB_RECIP_DEVICE, 0,
5049					&devstat);
5050			if (status) {
5051				dev_dbg(&udev->dev, "get status %d ?\n", status);
5052				goto loop_disable;
5053			}
5054			if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
5055				dev_err(&udev->dev,
5056					"can't connect bus-powered hub "
5057					"to this port\n");
5058				if (hub->has_indicators) {
5059					hub->indicator[port1-1] =
5060						INDICATOR_AMBER_BLINK;
5061					queue_delayed_work(
5062						system_power_efficient_wq,
5063						&hub->leds, 0);
5064				}
5065				status = -ENOTCONN;	/* Don't retry */
5066				goto loop_disable;
5067			}
5068		}
5069
5070		/* check for devices running slower than they could */
5071		if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
5072				&& udev->speed == USB_SPEED_FULL
5073				&& highspeed_hubs != 0)
5074			check_highspeed(hub, udev, port1);
5075
5076		/* Store the parent's children[] pointer.  At this point
5077		 * udev becomes globally accessible, although presumably
5078		 * no one will look at it until hdev is unlocked.
5079		 */
5080		status = 0;
5081
5082		mutex_lock(&usb_port_peer_mutex);
5083
5084		/* We mustn't add new devices if the parent hub has
5085		 * been disconnected; we would race with the
5086		 * recursively_mark_NOTATTACHED() routine.
5087		 */
5088		spin_lock_irq(&device_state_lock);
5089		if (hdev->state == USB_STATE_NOTATTACHED)
5090			status = -ENOTCONN;
5091		else
5092			port_dev->child = udev;
5093		spin_unlock_irq(&device_state_lock);
5094		mutex_unlock(&usb_port_peer_mutex);
5095
5096		/* Run it through the hoops (find a driver, etc) */
5097		if (!status) {
5098			status = usb_new_device(udev);
5099			if (status) {
5100				mutex_lock(&usb_port_peer_mutex);
5101				spin_lock_irq(&device_state_lock);
5102				port_dev->child = NULL;
5103				spin_unlock_irq(&device_state_lock);
5104				mutex_unlock(&usb_port_peer_mutex);
5105			} else {
5106				if (hcd->usb_phy && !hdev->parent)
5107					usb_phy_notify_connect(hcd->usb_phy,
5108							udev->speed);
5109			}
5110		}
5111
5112		if (status)
5113			goto loop_disable;
5114
5115		status = hub_power_remaining(hub);
5116		if (status)
5117			dev_dbg(hub->intfdev, "%dmA power budget left\n", status);
5118
5119		return;
5120
5121loop_disable:
5122		hub_port_disable(hub, port1, 1);
5123loop:
5124		usb_ep0_reinit(udev);
5125		release_devnum(udev);
5126		hub_free_dev(udev);
5127		usb_put_dev(udev);
5128		if ((status == -ENOTCONN) || (status == -ENOTSUPP))
5129			break;
5130
5131		/* When halfway through our retry count, power-cycle the port */
5132		if (i == (SET_CONFIG_TRIES / 2) - 1) {
5133			dev_info(&port_dev->dev, "attempt power cycle\n");
5134			usb_hub_set_port_power(hdev, hub, port1, false);
5135			msleep(2 * hub_power_on_good_delay(hub));
5136			usb_hub_set_port_power(hdev, hub, port1, true);
5137			msleep(hub_power_on_good_delay(hub));
5138		}
5139	}
5140	if (hub->hdev->parent ||
5141			!hcd->driver->port_handed_over ||
5142			!(hcd->driver->port_handed_over)(hcd, port1)) {
5143		if (status != -ENOTCONN && status != -ENODEV)
5144			dev_err(&port_dev->dev,
5145					"unable to enumerate USB device\n");
5146	}
5147
5148done:
5149	hub_port_disable(hub, port1, 1);
5150	if (hcd->driver->relinquish_port && !hub->hdev->parent) {
5151		if (status != -ENOTCONN && status != -ENODEV)
5152			hcd->driver->relinquish_port(hcd, port1);
5153	}
5154}
5155
5156/* Handle physical or logical connection change events.
5157 * This routine is called when:
5158 *	a port connection-change occurs;
5159 *	a port enable-change occurs (often caused by EMI);
5160 *	usb_reset_and_verify_device() encounters changed descriptors (as from
5161 *		a firmware download)
5162 * caller already locked the hub
5163 */
5164static void hub_port_connect_change(struct usb_hub *hub, int port1,
5165					u16 portstatus, u16 portchange)
5166		__must_hold(&port_dev->status_lock)
5167{
5168	struct usb_port *port_dev = hub->ports[port1 - 1];
5169	struct usb_device *udev = port_dev->child;
5170	int status = -ENODEV;
5171
5172	dev_dbg(&port_dev->dev, "status %04x, change %04x, %s\n", portstatus,
5173			portchange, portspeed(hub, portstatus));
5174
5175	if (hub->has_indicators) {
5176		set_port_led(hub, port1, HUB_LED_AUTO);
5177		hub->indicator[port1-1] = INDICATOR_AUTO;
5178	}
5179
5180#ifdef	CONFIG_USB_OTG
5181	/* during HNP, don't repeat the debounce */
5182	if (hub->hdev->bus->is_b_host)
5183		portchange &= ~(USB_PORT_STAT_C_CONNECTION |
5184				USB_PORT_STAT_C_ENABLE);
5185#endif
5186
5187	/* Try to resuscitate an existing device */
5188	if ((portstatus & USB_PORT_STAT_CONNECTION) && udev &&
5189			udev->state != USB_STATE_NOTATTACHED) {
5190		if (portstatus & USB_PORT_STAT_ENABLE) {
5191			status = 0;		/* Nothing to do */
5192#ifdef CONFIG_PM
5193		} else if (udev->state == USB_STATE_SUSPENDED &&
5194				udev->persist_enabled) {
5195			/* For a suspended device, treat this as a
5196			 * remote wakeup event.
5197			 */
5198			usb_unlock_port(port_dev);
5199			status = usb_remote_wakeup(udev);
5200			usb_lock_port(port_dev);
5201#endif
5202		} else {
5203			/* Don't resuscitate */;
5204		}
5205	}
5206	clear_bit(port1, hub->change_bits);
5207
5208	/* successfully revalidated the connection */
5209	if (status == 0)
5210		return;
5211
5212	usb_unlock_port(port_dev);
5213	hub_port_connect(hub, port1, portstatus, portchange);
5214	usb_lock_port(port_dev);
5215}
5216
5217/* Handle notifying userspace about hub over-current events */
5218static void port_over_current_notify(struct usb_port *port_dev)
5219{
5220	char *envp[3];
5221	struct device *hub_dev;
5222	char *port_dev_path;
5223
5224	sysfs_notify(&port_dev->dev.kobj, NULL, "over_current_count");
5225
5226	hub_dev = port_dev->dev.parent;
5227
5228	if (!hub_dev)
5229		return;
5230
5231	port_dev_path = kobject_get_path(&port_dev->dev.kobj, GFP_KERNEL);
5232	if (!port_dev_path)
5233		return;
5234
5235	envp[0] = kasprintf(GFP_KERNEL, "OVER_CURRENT_PORT=%s", port_dev_path);
5236	if (!envp[0])
5237		goto exit_path;
5238
5239	envp[1] = kasprintf(GFP_KERNEL, "OVER_CURRENT_COUNT=%u",
5240			port_dev->over_current_count);
5241	if (!envp[1])
5242		goto exit;
5243
5244	envp[2] = NULL;
5245	kobject_uevent_env(&hub_dev->kobj, KOBJ_CHANGE, envp);
5246
5247	kfree(envp[1]);
5248exit:
5249	kfree(envp[0]);
5250exit_path:
5251	kfree(port_dev_path);
5252}
5253
5254static void port_event(struct usb_hub *hub, int port1)
5255		__must_hold(&port_dev->status_lock)
5256{
5257	int connect_change;
5258	struct usb_port *port_dev = hub->ports[port1 - 1];
5259	struct usb_device *udev = port_dev->child;
5260	struct usb_device *hdev = hub->hdev;
5261	u16 portstatus, portchange;
5262
5263	connect_change = test_bit(port1, hub->change_bits);
5264	clear_bit(port1, hub->event_bits);
5265	clear_bit(port1, hub->wakeup_bits);
5266
5267	if (hub_port_status(hub, port1, &portstatus, &portchange) < 0)
5268		return;
5269
5270	if (portchange & USB_PORT_STAT_C_CONNECTION) {
5271		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
5272		connect_change = 1;
5273	}
5274
5275	if (portchange & USB_PORT_STAT_C_ENABLE) {
5276		if (!connect_change)
5277			dev_dbg(&port_dev->dev, "enable change, status %08x\n",
5278					portstatus);
5279		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
5280
5281		/*
5282		 * EM interference sometimes causes badly shielded USB devices
5283		 * to be shutdown by the hub, this hack enables them again.
5284		 * Works at least with mouse driver.
5285		 */
5286		if (!(portstatus & USB_PORT_STAT_ENABLE)
5287		    && !connect_change && udev) {
5288			dev_err(&port_dev->dev, "disabled by hub (EMI?), re-enabling...\n");
5289			connect_change = 1;
5290		}
5291	}
5292
5293	if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
5294		u16 status = 0, unused;
5295		port_dev->over_current_count++;
5296		port_over_current_notify(port_dev);
5297
5298		dev_dbg(&port_dev->dev, "over-current change #%u\n",
5299			port_dev->over_current_count);
5300		usb_clear_port_feature(hdev, port1,
5301				USB_PORT_FEAT_C_OVER_CURRENT);
5302		msleep(100);	/* Cool down */
5303		hub_power_on(hub, true);
5304		hub_port_status(hub, port1, &status, &unused);
5305		if (status & USB_PORT_STAT_OVERCURRENT)
5306			dev_err(&port_dev->dev, "over-current condition\n");
5307	}
5308
5309	if (portchange & USB_PORT_STAT_C_RESET) {
5310		dev_dbg(&port_dev->dev, "reset change\n");
5311		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_RESET);
5312	}
5313	if ((portchange & USB_PORT_STAT_C_BH_RESET)
5314	    && hub_is_superspeed(hdev)) {
5315		dev_dbg(&port_dev->dev, "warm reset change\n");
5316		usb_clear_port_feature(hdev, port1,
5317				USB_PORT_FEAT_C_BH_PORT_RESET);
5318	}
5319	if (portchange & USB_PORT_STAT_C_LINK_STATE) {
5320		dev_dbg(&port_dev->dev, "link state change\n");
5321		usb_clear_port_feature(hdev, port1,
5322				USB_PORT_FEAT_C_PORT_LINK_STATE);
5323	}
5324	if (portchange & USB_PORT_STAT_C_CONFIG_ERROR) {
5325		dev_warn(&port_dev->dev, "config error\n");
5326		usb_clear_port_feature(hdev, port1,
5327				USB_PORT_FEAT_C_PORT_CONFIG_ERROR);
5328	}
5329
5330	/* skip port actions that require the port to be powered on */
5331	if (!pm_runtime_active(&port_dev->dev))
5332		return;
5333
5334	if (hub_handle_remote_wakeup(hub, port1, portstatus, portchange))
5335		connect_change = 1;
5336
5337	/*
5338	 * Warm reset a USB3 protocol port if it's in
5339	 * SS.Inactive state.
5340	 */
5341	if (hub_port_warm_reset_required(hub, port1, portstatus)) {
5342		dev_dbg(&port_dev->dev, "do warm reset\n");
5343		if (!udev || !(portstatus & USB_PORT_STAT_CONNECTION)
5344				|| udev->state == USB_STATE_NOTATTACHED) {
5345			if (hub_port_reset(hub, port1, NULL,
5346					HUB_BH_RESET_TIME, true) < 0)
5347				hub_port_disable(hub, port1, 1);
5348		} else {
5349			usb_unlock_port(port_dev);
5350			usb_lock_device(udev);
5351			usb_reset_device(udev);
5352			usb_unlock_device(udev);
5353			usb_lock_port(port_dev);
5354			connect_change = 0;
5355		}
5356	}
5357
5358	if (connect_change)
5359		hub_port_connect_change(hub, port1, portstatus, portchange);
5360}
5361
5362static void hub_event(struct work_struct *work)
5363{
5364	struct usb_device *hdev;
5365	struct usb_interface *intf;
5366	struct usb_hub *hub;
5367	struct device *hub_dev;
5368	u16 hubstatus;
5369	u16 hubchange;
5370	int i, ret;
5371
5372	hub = container_of(work, struct usb_hub, events);
5373	hdev = hub->hdev;
5374	hub_dev = hub->intfdev;
5375	intf = to_usb_interface(hub_dev);
5376
5377	dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
5378			hdev->state, hdev->maxchild,
5379			/* NOTE: expects max 15 ports... */
5380			(u16) hub->change_bits[0],
5381			(u16) hub->event_bits[0]);
5382
5383	/* Lock the device, then check to see if we were
5384	 * disconnected while waiting for the lock to succeed. */
5385	usb_lock_device(hdev);
5386	if (unlikely(hub->disconnected))
5387		goto out_hdev_lock;
5388
5389	/* If the hub has died, clean up after it */
5390	if (hdev->state == USB_STATE_NOTATTACHED) {
5391		hub->error = -ENODEV;
5392		hub_quiesce(hub, HUB_DISCONNECT);
5393		goto out_hdev_lock;
5394	}
5395
5396	/* Autoresume */
5397	ret = usb_autopm_get_interface(intf);
5398	if (ret) {
5399		dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
5400		goto out_hdev_lock;
5401	}
5402
5403	/* If this is an inactive hub, do nothing */
5404	if (hub->quiescing)
5405		goto out_autopm;
5406
5407	if (hub->error) {
5408		dev_dbg(hub_dev, "resetting for error %d\n", hub->error);
5409
5410		ret = usb_reset_device(hdev);
5411		if (ret) {
5412			dev_dbg(hub_dev, "error resetting hub: %d\n", ret);
5413			goto out_autopm;
5414		}
5415
5416		hub->nerrors = 0;
5417		hub->error = 0;
5418	}
5419
5420	/* deal with port status changes */
5421	for (i = 1; i <= hdev->maxchild; i++) {
5422		struct usb_port *port_dev = hub->ports[i - 1];
5423
5424		if (test_bit(i, hub->event_bits)
5425				|| test_bit(i, hub->change_bits)
5426				|| test_bit(i, hub->wakeup_bits)) {
5427			/*
5428			 * The get_noresume and barrier ensure that if
5429			 * the port was in the process of resuming, we
5430			 * flush that work and keep the port active for
5431			 * the duration of the port_event().  However,
5432			 * if the port is runtime pm suspended
5433			 * (powered-off), we leave it in that state, run
5434			 * an abbreviated port_event(), and move on.
5435			 */
5436			pm_runtime_get_noresume(&port_dev->dev);
5437			pm_runtime_barrier(&port_dev->dev);
5438			usb_lock_port(port_dev);
5439			port_event(hub, i);
5440			usb_unlock_port(port_dev);
5441			pm_runtime_put_sync(&port_dev->dev);
5442		}
5443	}
5444
5445	/* deal with hub status changes */
5446	if (test_and_clear_bit(0, hub->event_bits) == 0)
5447		;	/* do nothing */
5448	else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
5449		dev_err(hub_dev, "get_hub_status failed\n");
5450	else {
5451		if (hubchange & HUB_CHANGE_LOCAL_POWER) {
5452			dev_dbg(hub_dev, "power change\n");
5453			clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
5454			if (hubstatus & HUB_STATUS_LOCAL_POWER)
5455				/* FIXME: Is this always true? */
5456				hub->limited_power = 1;
5457			else
5458				hub->limited_power = 0;
5459		}
5460		if (hubchange & HUB_CHANGE_OVERCURRENT) {
5461			u16 status = 0;
5462			u16 unused;
5463
5464			dev_dbg(hub_dev, "over-current change\n");
5465			clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
5466			msleep(500);	/* Cool down */
5467			hub_power_on(hub, true);
5468			hub_hub_status(hub, &status, &unused);
5469			if (status & HUB_STATUS_OVERCURRENT)
5470				dev_err(hub_dev, "over-current condition\n");
5471		}
5472	}
5473
5474out_autopm:
5475	/* Balance the usb_autopm_get_interface() above */
5476	usb_autopm_put_interface_no_suspend(intf);
5477out_hdev_lock:
5478	usb_unlock_device(hdev);
5479
5480	/* Balance the stuff in kick_hub_wq() and allow autosuspend */
5481	usb_autopm_put_interface(intf);
5482	kref_put(&hub->kref, hub_release);
5483}
5484
5485static const struct usb_device_id hub_id_table[] = {
5486    { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5487			| USB_DEVICE_ID_MATCH_INT_CLASS,
5488      .idVendor = USB_VENDOR_GENESYS_LOGIC,
5489      .bInterfaceClass = USB_CLASS_HUB,
5490      .driver_info = HUB_QUIRK_CHECK_PORT_AUTOSUSPEND},
5491    { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
5492      .bDeviceClass = USB_CLASS_HUB},
5493    { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
5494      .bInterfaceClass = USB_CLASS_HUB},
5495    { }						/* Terminating entry */
5496};
5497
5498MODULE_DEVICE_TABLE(usb, hub_id_table);
5499
5500static struct usb_driver hub_driver = {
5501	.name =		"hub",
5502	.probe =	hub_probe,
5503	.disconnect =	hub_disconnect,
5504	.suspend =	hub_suspend,
5505	.resume =	hub_resume,
5506	.reset_resume =	hub_reset_resume,
5507	.pre_reset =	hub_pre_reset,
5508	.post_reset =	hub_post_reset,
5509	.unlocked_ioctl = hub_ioctl,
5510	.id_table =	hub_id_table,
5511	.supports_autosuspend =	1,
5512};
5513
5514int usb_hub_init(void)
5515{
5516	if (usb_register(&hub_driver) < 0) {
5517		printk(KERN_ERR "%s: can't register hub driver\n",
5518			usbcore_name);
5519		return -1;
5520	}
5521
5522	/*
5523	 * The workqueue needs to be freezable to avoid interfering with
5524	 * USB-PERSIST port handover. Otherwise it might see that a full-speed
5525	 * device was gone before the EHCI controller had handed its port
5526	 * over to the companion full-speed controller.
5527	 */
5528	hub_wq = alloc_workqueue("usb_hub_wq", WQ_FREEZABLE, 0);
5529	if (hub_wq)
5530		return 0;
5531
5532	/* Fall through if kernel_thread failed */
5533	usb_deregister(&hub_driver);
5534	pr_err("%s: can't allocate workqueue for usb hub\n", usbcore_name);
5535
5536	return -1;
5537}
5538
5539void usb_hub_cleanup(void)
5540{
5541	destroy_workqueue(hub_wq);
5542
5543	/*
5544	 * Hub resources are freed for us by usb_deregister. It calls
5545	 * usb_driver_purge on every device which in turn calls that
5546	 * devices disconnect function if it is using this driver.
5547	 * The hub_disconnect function takes care of releasing the
5548	 * individual hub resources. -greg
5549	 */
5550	usb_deregister(&hub_driver);
5551} /* usb_hub_cleanup() */
5552
5553static int descriptors_changed(struct usb_device *udev,
5554		struct usb_device_descriptor *old_device_descriptor,
5555		struct usb_host_bos *old_bos)
5556{
5557	int		changed = 0;
5558	unsigned	index;
5559	unsigned	serial_len = 0;
5560	unsigned	len;
5561	unsigned	old_length;
5562	int		length;
5563	char		*buf;
5564
5565	if (memcmp(&udev->descriptor, old_device_descriptor,
5566			sizeof(*old_device_descriptor)) != 0)
5567		return 1;
5568
5569	if ((old_bos && !udev->bos) || (!old_bos && udev->bos))
5570		return 1;
5571	if (udev->bos) {
5572		len = le16_to_cpu(udev->bos->desc->wTotalLength);
5573		if (len != le16_to_cpu(old_bos->desc->wTotalLength))
5574			return 1;
5575		if (memcmp(udev->bos->desc, old_bos->desc, len))
5576			return 1;
5577	}
5578
5579	/* Since the idVendor, idProduct, and bcdDevice values in the
5580	 * device descriptor haven't changed, we will assume the
5581	 * Manufacturer and Product strings haven't changed either.
5582	 * But the SerialNumber string could be different (e.g., a
5583	 * different flash card of the same brand).
5584	 */
5585	if (udev->serial)
5586		serial_len = strlen(udev->serial) + 1;
5587
5588	len = serial_len;
5589	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
5590		old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
5591		len = max(len, old_length);
5592	}
5593
5594	buf = kmalloc(len, GFP_NOIO);
5595	if (!buf)
5596		/* assume the worst */
5597		return 1;
5598
5599	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
5600		old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
5601		length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
5602				old_length);
5603		if (length != old_length) {
5604			dev_dbg(&udev->dev, "config index %d, error %d\n",
5605					index, length);
5606			changed = 1;
5607			break;
5608		}
5609		if (memcmp(buf, udev->rawdescriptors[index], old_length)
5610				!= 0) {
5611			dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
5612				index,
5613				((struct usb_config_descriptor *) buf)->
5614					bConfigurationValue);
5615			changed = 1;
5616			break;
5617		}
5618	}
5619
5620	if (!changed && serial_len) {
5621		length = usb_string(udev, udev->descriptor.iSerialNumber,
5622				buf, serial_len);
5623		if (length + 1 != serial_len) {
5624			dev_dbg(&udev->dev, "serial string error %d\n",
5625					length);
5626			changed = 1;
5627		} else if (memcmp(buf, udev->serial, length) != 0) {
5628			dev_dbg(&udev->dev, "serial string changed\n");
5629			changed = 1;
5630		}
5631	}
5632
5633	kfree(buf);
5634	return changed;
5635}
5636
5637/**
5638 * usb_reset_and_verify_device - perform a USB port reset to reinitialize a device
5639 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
5640 *
5641 * WARNING - don't use this routine to reset a composite device
5642 * (one with multiple interfaces owned by separate drivers)!
5643 * Use usb_reset_device() instead.
5644 *
5645 * Do a port reset, reassign the device's address, and establish its
5646 * former operating configuration.  If the reset fails, or the device's
5647 * descriptors change from their values before the reset, or the original
5648 * configuration and altsettings cannot be restored, a flag will be set
5649 * telling hub_wq to pretend the device has been disconnected and then
5650 * re-connected.  All drivers will be unbound, and the device will be
5651 * re-enumerated and probed all over again.
5652 *
5653 * Return: 0 if the reset succeeded, -ENODEV if the device has been
5654 * flagged for logical disconnection, or some other negative error code
5655 * if the reset wasn't even attempted.
5656 *
5657 * Note:
5658 * The caller must own the device lock and the port lock, the latter is
5659 * taken by usb_reset_device().  For example, it's safe to use
5660 * usb_reset_device() from a driver probe() routine after downloading
5661 * new firmware.  For calls that might not occur during probe(), drivers
5662 * should lock the device using usb_lock_device_for_reset().
5663 *
5664 * Locking exception: This routine may also be called from within an
5665 * autoresume handler.  Such usage won't conflict with other tasks
5666 * holding the device lock because these tasks should always call
5667 * usb_autopm_resume_device(), thereby preventing any unwanted
5668 * autoresume.  The autoresume handler is expected to have already
5669 * acquired the port lock before calling this routine.
5670 */
5671static int usb_reset_and_verify_device(struct usb_device *udev)
5672{
5673	struct usb_device		*parent_hdev = udev->parent;
5674	struct usb_hub			*parent_hub;
5675	struct usb_hcd			*hcd = bus_to_hcd(udev->bus);
5676	struct usb_device_descriptor	descriptor = udev->descriptor;
5677	struct usb_host_bos		*bos;
5678	int				i, j, ret = 0;
5679	int				port1 = udev->portnum;
5680
5681	if (udev->state == USB_STATE_NOTATTACHED ||
5682			udev->state == USB_STATE_SUSPENDED) {
5683		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
5684				udev->state);
5685		return -EINVAL;
5686	}
5687
5688	if (!parent_hdev)
5689		return -EISDIR;
5690
5691	parent_hub = usb_hub_to_struct_hub(parent_hdev);
5692
5693	/* Disable USB2 hardware LPM.
5694	 * It will be re-enabled by the enumeration process.
5695	 */
5696	usb_disable_usb2_hardware_lpm(udev);
 
5697
5698	/* Disable LPM while we reset the device and reinstall the alt settings.
5699	 * Device-initiated LPM, and system exit latency settings are cleared
5700	 * when the device is reset, so we have to set them up again.
5701	 */
5702	ret = usb_unlocked_disable_lpm(udev);
5703	if (ret) {
5704		dev_err(&udev->dev, "%s Failed to disable LPM\n", __func__);
5705		goto re_enumerate_no_bos;
5706	}
5707
5708	bos = udev->bos;
5709	udev->bos = NULL;
5710
5711	for (i = 0; i < SET_CONFIG_TRIES; ++i) {
5712
5713		/* ep0 maxpacket size may change; let the HCD know about it.
5714		 * Other endpoints will be handled by re-enumeration. */
5715		usb_ep0_reinit(udev);
5716		ret = hub_port_init(parent_hub, udev, port1, i);
5717		if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
5718			break;
5719	}
5720
5721	if (ret < 0)
5722		goto re_enumerate;
5723
5724	/* Device might have changed firmware (DFU or similar) */
5725	if (descriptors_changed(udev, &descriptor, bos)) {
5726		dev_info(&udev->dev, "device firmware changed\n");
5727		udev->descriptor = descriptor;	/* for disconnect() calls */
5728		goto re_enumerate;
5729	}
5730
5731	/* Restore the device's previous configuration */
5732	if (!udev->actconfig)
5733		goto done;
5734
5735	mutex_lock(hcd->bandwidth_mutex);
5736	ret = usb_hcd_alloc_bandwidth(udev, udev->actconfig, NULL, NULL);
5737	if (ret < 0) {
5738		dev_warn(&udev->dev,
5739				"Busted HC?  Not enough HCD resources for "
5740				"old configuration.\n");
5741		mutex_unlock(hcd->bandwidth_mutex);
5742		goto re_enumerate;
5743	}
5744	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
5745			USB_REQ_SET_CONFIGURATION, 0,
5746			udev->actconfig->desc.bConfigurationValue, 0,
5747			NULL, 0, USB_CTRL_SET_TIMEOUT);
5748	if (ret < 0) {
5749		dev_err(&udev->dev,
5750			"can't restore configuration #%d (error=%d)\n",
5751			udev->actconfig->desc.bConfigurationValue, ret);
5752		mutex_unlock(hcd->bandwidth_mutex);
5753		goto re_enumerate;
5754	}
5755	mutex_unlock(hcd->bandwidth_mutex);
5756	usb_set_device_state(udev, USB_STATE_CONFIGURED);
5757
5758	/* Put interfaces back into the same altsettings as before.
5759	 * Don't bother to send the Set-Interface request for interfaces
5760	 * that were already in altsetting 0; besides being unnecessary,
5761	 * many devices can't handle it.  Instead just reset the host-side
5762	 * endpoint state.
5763	 */
5764	for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
5765		struct usb_host_config *config = udev->actconfig;
5766		struct usb_interface *intf = config->interface[i];
5767		struct usb_interface_descriptor *desc;
5768
5769		desc = &intf->cur_altsetting->desc;
5770		if (desc->bAlternateSetting == 0) {
5771			usb_disable_interface(udev, intf, true);
5772			usb_enable_interface(udev, intf, true);
5773			ret = 0;
5774		} else {
5775			/* Let the bandwidth allocation function know that this
5776			 * device has been reset, and it will have to use
5777			 * alternate setting 0 as the current alternate setting.
5778			 */
5779			intf->resetting_device = 1;
5780			ret = usb_set_interface(udev, desc->bInterfaceNumber,
5781					desc->bAlternateSetting);
5782			intf->resetting_device = 0;
5783		}
5784		if (ret < 0) {
5785			dev_err(&udev->dev, "failed to restore interface %d "
5786				"altsetting %d (error=%d)\n",
5787				desc->bInterfaceNumber,
5788				desc->bAlternateSetting,
5789				ret);
5790			goto re_enumerate;
5791		}
5792		/* Resetting also frees any allocated streams */
5793		for (j = 0; j < intf->cur_altsetting->desc.bNumEndpoints; j++)
5794			intf->cur_altsetting->endpoint[j].streams = 0;
5795	}
5796
5797done:
5798	/* Now that the alt settings are re-installed, enable LTM and LPM. */
5799	usb_enable_usb2_hardware_lpm(udev);
5800	usb_unlocked_enable_lpm(udev);
5801	usb_enable_ltm(udev);
5802	usb_release_bos_descriptor(udev);
5803	udev->bos = bos;
5804	return 0;
5805
5806re_enumerate:
5807	usb_release_bos_descriptor(udev);
5808	udev->bos = bos;
5809re_enumerate_no_bos:
5810	/* LPM state doesn't matter when we're about to destroy the device. */
5811	hub_port_logical_disconnect(parent_hub, port1);
5812	return -ENODEV;
5813}
5814
5815/**
5816 * usb_reset_device - warn interface drivers and perform a USB port reset
5817 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
5818 *
5819 * Warns all drivers bound to registered interfaces (using their pre_reset
5820 * method), performs the port reset, and then lets the drivers know that
5821 * the reset is over (using their post_reset method).
5822 *
5823 * Return: The same as for usb_reset_and_verify_device().
5824 *
5825 * Note:
5826 * The caller must own the device lock.  For example, it's safe to use
5827 * this from a driver probe() routine after downloading new firmware.
5828 * For calls that might not occur during probe(), drivers should lock
5829 * the device using usb_lock_device_for_reset().
5830 *
5831 * If an interface is currently being probed or disconnected, we assume
5832 * its driver knows how to handle resets.  For all other interfaces,
5833 * if the driver doesn't have pre_reset and post_reset methods then
5834 * we attempt to unbind it and rebind afterward.
5835 */
5836int usb_reset_device(struct usb_device *udev)
5837{
5838	int ret;
5839	int i;
5840	unsigned int noio_flag;
5841	struct usb_port *port_dev;
5842	struct usb_host_config *config = udev->actconfig;
5843	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
5844
5845	if (udev->state == USB_STATE_NOTATTACHED ||
5846			udev->state == USB_STATE_SUSPENDED) {
5847		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
5848				udev->state);
5849		return -EINVAL;
5850	}
5851
5852	if (!udev->parent) {
5853		/* this requires hcd-specific logic; see ohci_restart() */
5854		dev_dbg(&udev->dev, "%s for root hub!\n", __func__);
5855		return -EISDIR;
5856	}
5857
5858	port_dev = hub->ports[udev->portnum - 1];
5859
5860	/*
5861	 * Don't allocate memory with GFP_KERNEL in current
5862	 * context to avoid possible deadlock if usb mass
5863	 * storage interface or usbnet interface(iSCSI case)
5864	 * is included in current configuration. The easist
5865	 * approach is to do it for every device reset,
5866	 * because the device 'memalloc_noio' flag may have
5867	 * not been set before reseting the usb device.
5868	 */
5869	noio_flag = memalloc_noio_save();
5870
5871	/* Prevent autosuspend during the reset */
5872	usb_autoresume_device(udev);
5873
5874	if (config) {
5875		for (i = 0; i < config->desc.bNumInterfaces; ++i) {
5876			struct usb_interface *cintf = config->interface[i];
5877			struct usb_driver *drv;
5878			int unbind = 0;
5879
5880			if (cintf->dev.driver) {
5881				drv = to_usb_driver(cintf->dev.driver);
5882				if (drv->pre_reset && drv->post_reset)
5883					unbind = (drv->pre_reset)(cintf);
5884				else if (cintf->condition ==
5885						USB_INTERFACE_BOUND)
5886					unbind = 1;
5887				if (unbind)
5888					usb_forced_unbind_intf(cintf);
5889			}
5890		}
5891	}
5892
5893	usb_lock_port(port_dev);
5894	ret = usb_reset_and_verify_device(udev);
5895	usb_unlock_port(port_dev);
5896
5897	if (config) {
5898		for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
5899			struct usb_interface *cintf = config->interface[i];
5900			struct usb_driver *drv;
5901			int rebind = cintf->needs_binding;
5902
5903			if (!rebind && cintf->dev.driver) {
5904				drv = to_usb_driver(cintf->dev.driver);
5905				if (drv->post_reset)
5906					rebind = (drv->post_reset)(cintf);
5907				else if (cintf->condition ==
5908						USB_INTERFACE_BOUND)
5909					rebind = 1;
5910				if (rebind)
5911					cintf->needs_binding = 1;
5912			}
5913		}
5914
5915		/* If the reset failed, hub_wq will unbind drivers later */
5916		if (ret == 0)
5917			usb_unbind_and_rebind_marked_interfaces(udev);
5918	}
5919
5920	usb_autosuspend_device(udev);
5921	memalloc_noio_restore(noio_flag);
5922	return ret;
5923}
5924EXPORT_SYMBOL_GPL(usb_reset_device);
5925
5926
5927/**
5928 * usb_queue_reset_device - Reset a USB device from an atomic context
5929 * @iface: USB interface belonging to the device to reset
5930 *
5931 * This function can be used to reset a USB device from an atomic
5932 * context, where usb_reset_device() won't work (as it blocks).
5933 *
5934 * Doing a reset via this method is functionally equivalent to calling
5935 * usb_reset_device(), except for the fact that it is delayed to a
5936 * workqueue. This means that any drivers bound to other interfaces
5937 * might be unbound, as well as users from usbfs in user space.
5938 *
5939 * Corner cases:
5940 *
5941 * - Scheduling two resets at the same time from two different drivers
5942 *   attached to two different interfaces of the same device is
5943 *   possible; depending on how the driver attached to each interface
5944 *   handles ->pre_reset(), the second reset might happen or not.
5945 *
5946 * - If the reset is delayed so long that the interface is unbound from
5947 *   its driver, the reset will be skipped.
5948 *
5949 * - This function can be called during .probe().  It can also be called
5950 *   during .disconnect(), but doing so is pointless because the reset
5951 *   will not occur.  If you really want to reset the device during
5952 *   .disconnect(), call usb_reset_device() directly -- but watch out
5953 *   for nested unbinding issues!
5954 */
5955void usb_queue_reset_device(struct usb_interface *iface)
5956{
5957	if (schedule_work(&iface->reset_ws))
5958		usb_get_intf(iface);
5959}
5960EXPORT_SYMBOL_GPL(usb_queue_reset_device);
5961
5962/**
5963 * usb_hub_find_child - Get the pointer of child device
5964 * attached to the port which is specified by @port1.
5965 * @hdev: USB device belonging to the usb hub
5966 * @port1: port num to indicate which port the child device
5967 *	is attached to.
5968 *
5969 * USB drivers call this function to get hub's child device
5970 * pointer.
5971 *
5972 * Return: %NULL if input param is invalid and
5973 * child's usb_device pointer if non-NULL.
5974 */
5975struct usb_device *usb_hub_find_child(struct usb_device *hdev,
5976		int port1)
5977{
5978	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
5979
5980	if (port1 < 1 || port1 > hdev->maxchild)
5981		return NULL;
5982	return hub->ports[port1 - 1]->child;
5983}
5984EXPORT_SYMBOL_GPL(usb_hub_find_child);
5985
5986void usb_hub_adjust_deviceremovable(struct usb_device *hdev,
5987		struct usb_hub_descriptor *desc)
5988{
5989	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
5990	enum usb_port_connect_type connect_type;
5991	int i;
5992
5993	if (!hub)
5994		return;
5995
5996	if (!hub_is_superspeed(hdev)) {
5997		for (i = 1; i <= hdev->maxchild; i++) {
5998			struct usb_port *port_dev = hub->ports[i - 1];
5999
6000			connect_type = port_dev->connect_type;
6001			if (connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
6002				u8 mask = 1 << (i%8);
6003
6004				if (!(desc->u.hs.DeviceRemovable[i/8] & mask)) {
6005					dev_dbg(&port_dev->dev, "DeviceRemovable is changed to 1 according to platform information.\n");
6006					desc->u.hs.DeviceRemovable[i/8]	|= mask;
6007				}
6008			}
6009		}
6010	} else {
6011		u16 port_removable = le16_to_cpu(desc->u.ss.DeviceRemovable);
6012
6013		for (i = 1; i <= hdev->maxchild; i++) {
6014			struct usb_port *port_dev = hub->ports[i - 1];
6015
6016			connect_type = port_dev->connect_type;
6017			if (connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
6018				u16 mask = 1 << i;
6019
6020				if (!(port_removable & mask)) {
6021					dev_dbg(&port_dev->dev, "DeviceRemovable is changed to 1 according to platform information.\n");
6022					port_removable |= mask;
6023				}
6024			}
6025		}
6026
6027		desc->u.ss.DeviceRemovable = cpu_to_le16(port_removable);
6028	}
6029}
6030
6031#ifdef CONFIG_ACPI
6032/**
6033 * usb_get_hub_port_acpi_handle - Get the usb port's acpi handle
6034 * @hdev: USB device belonging to the usb hub
6035 * @port1: port num of the port
6036 *
6037 * Return: Port's acpi handle if successful, %NULL if params are
6038 * invalid.
6039 */
6040acpi_handle usb_get_hub_port_acpi_handle(struct usb_device *hdev,
6041	int port1)
6042{
6043	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
6044
6045	if (!hub)
6046		return NULL;
6047
6048	return ACPI_HANDLE(&hub->ports[port1 - 1]->dev);
6049}
6050#endif