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/kcov.h>
  22#include <linux/ioctl.h>
  23#include <linux/usb.h>
  24#include <linux/usbdevice_fs.h>
  25#include <linux/usb/hcd.h>
  26#include <linux/usb/onboard_dev.h>
  27#include <linux/usb/otg.h>
  28#include <linux/usb/quirks.h>
  29#include <linux/workqueue.h>
  30#include <linux/mutex.h>
  31#include <linux/random.h>
  32#include <linux/pm_qos.h>
  33#include <linux/kobject.h>
  34
  35#include <linux/bitfield.h>
  36#include <linux/uaccess.h>
  37#include <asm/byteorder.h>
  38
  39#include "hub.h"
  40#include "phy.h"
  41#include "otg_productlist.h"
  42
  43#define USB_VENDOR_GENESYS_LOGIC		0x05e3
  44#define USB_VENDOR_SMSC				0x0424
  45#define USB_PRODUCT_USB5534B			0x5534
  46#define USB_VENDOR_CYPRESS			0x04b4
  47#define USB_PRODUCT_CY7C65632			0x6570
  48#define USB_VENDOR_TEXAS_INSTRUMENTS		0x0451
  49#define USB_PRODUCT_TUSB8041_USB3		0x8140
  50#define USB_PRODUCT_TUSB8041_USB2		0x8142
  51#define USB_VENDOR_MICROCHIP			0x0424
  52#define USB_PRODUCT_USB4913			0x4913
  53#define USB_PRODUCT_USB4914			0x4914
  54#define USB_PRODUCT_USB4915			0x4915
  55#define HUB_QUIRK_CHECK_PORT_AUTOSUSPEND	BIT(0)
  56#define HUB_QUIRK_DISABLE_AUTOSUSPEND		BIT(1)
  57#define HUB_QUIRK_REDUCE_FRAME_INTR_BINTERVAL	BIT(2)
  58
  59#define USB_TP_TRANSMISSION_DELAY	40	/* ns */
  60#define USB_TP_TRANSMISSION_DELAY_MAX	65535	/* ns */
  61#define USB_PING_RESPONSE_TIME		400	/* ns */
  62#define USB_REDUCE_FRAME_INTR_BINTERVAL	9
  63
  64/*
  65 * The SET_ADDRESS request timeout will be 500 ms when
  66 * USB_QUIRK_SHORT_SET_ADDRESS_REQ_TIMEOUT quirk flag is set.
  67 */
  68#define USB_SHORT_SET_ADDRESS_REQ_TIMEOUT	500  /* ms */
  69
  70/* Protect struct usb_device->state and ->children members
  71 * Note: Both are also protected by ->dev.sem, except that ->state can
  72 * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
  73static DEFINE_SPINLOCK(device_state_lock);
  74
  75/* workqueue to process hub events */
  76static struct workqueue_struct *hub_wq;
  77static void hub_event(struct work_struct *work);
  78
  79/* synchronize hub-port add/remove and peering operations */
  80DEFINE_MUTEX(usb_port_peer_mutex);
  81
  82/* cycle leds on hubs that aren't blinking for attention */
  83static bool blinkenlights;
  84module_param(blinkenlights, bool, S_IRUGO);
  85MODULE_PARM_DESC(blinkenlights, "true to cycle leds on hubs");
  86
  87/*
  88 * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
  89 * 10 seconds to send reply for the initial 64-byte descriptor request.
  90 */
  91/* define initial 64-byte descriptor request timeout in milliseconds */
  92static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
  93module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
  94MODULE_PARM_DESC(initial_descriptor_timeout,
  95		"initial 64-byte descriptor request timeout in milliseconds "
  96		"(default 5000 - 5.0 seconds)");
  97
  98/*
  99 * As of 2.6.10 we introduce a new USB device initialization scheme which
 100 * closely resembles the way Windows works.  Hopefully it will be compatible
 101 * with a wider range of devices than the old scheme.  However some previously
 102 * working devices may start giving rise to "device not accepting address"
 103 * errors; if that happens the user can try the old scheme by adjusting the
 104 * following module parameters.
 105 *
 106 * For maximum flexibility there are two boolean parameters to control the
 107 * hub driver's behavior.  On the first initialization attempt, if the
 108 * "old_scheme_first" parameter is set then the old scheme will be used,
 109 * otherwise the new scheme is used.  If that fails and "use_both_schemes"
 110 * is set, then the driver will make another attempt, using the other scheme.
 111 */
 112static bool old_scheme_first;
 113module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
 114MODULE_PARM_DESC(old_scheme_first,
 115		 "start with the old device initialization scheme");
 116
 117static bool use_both_schemes = true;
 118module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
 119MODULE_PARM_DESC(use_both_schemes,
 120		"try the other device initialization scheme if the "
 121		"first one fails");
 122
 123/* Mutual exclusion for EHCI CF initialization.  This interferes with
 124 * port reset on some companion controllers.
 125 */
 126DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
 127EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
 128
 129#define HUB_DEBOUNCE_TIMEOUT	2000
 130#define HUB_DEBOUNCE_STEP	  25
 131#define HUB_DEBOUNCE_STABLE	 100
 132
 
 133static int usb_reset_and_verify_device(struct usb_device *udev);
 134static int hub_port_disable(struct usb_hub *hub, int port1, int set_state);
 135static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
 136		u16 portstatus);
 137
 138static inline char *portspeed(struct usb_hub *hub, int portstatus)
 139{
 140	if (hub_is_superspeedplus(hub->hdev))
 141		return "10.0 Gb/s";
 142	if (hub_is_superspeed(hub->hdev))
 143		return "5.0 Gb/s";
 144	if (portstatus & USB_PORT_STAT_HIGH_SPEED)
 145		return "480 Mb/s";
 146	else if (portstatus & USB_PORT_STAT_LOW_SPEED)
 147		return "1.5 Mb/s";
 148	else
 149		return "12 Mb/s";
 150}
 151
 152/* Note that hdev or one of its children must be locked! */
 153struct usb_hub *usb_hub_to_struct_hub(struct usb_device *hdev)
 154{
 155	if (!hdev || !hdev->actconfig || !hdev->maxchild)
 156		return NULL;
 157	return usb_get_intfdata(hdev->actconfig->interface[0]);
 158}
 159
 160int usb_device_supports_lpm(struct usb_device *udev)
 161{
 162	/* Some devices have trouble with LPM */
 163	if (udev->quirks & USB_QUIRK_NO_LPM)
 164		return 0;
 165
 166	/* Skip if the device BOS descriptor couldn't be read */
 167	if (!udev->bos)
 168		return 0;
 169
 170	/* USB 2.1 (and greater) devices indicate LPM support through
 171	 * their USB 2.0 Extended Capabilities BOS descriptor.
 172	 */
 173	if (udev->speed == USB_SPEED_HIGH || udev->speed == USB_SPEED_FULL) {
 174		if (udev->bos->ext_cap &&
 175			(USB_LPM_SUPPORT &
 176			 le32_to_cpu(udev->bos->ext_cap->bmAttributes)))
 177			return 1;
 178		return 0;
 179	}
 180
 181	/*
 182	 * According to the USB 3.0 spec, all USB 3.0 devices must support LPM.
 183	 * However, there are some that don't, and they set the U1/U2 exit
 184	 * latencies to zero.
 185	 */
 186	if (!udev->bos->ss_cap) {
 187		dev_info(&udev->dev, "No LPM exit latency info found, disabling LPM.\n");
 188		return 0;
 189	}
 190
 191	if (udev->bos->ss_cap->bU1devExitLat == 0 &&
 192			udev->bos->ss_cap->bU2DevExitLat == 0) {
 193		if (udev->parent)
 194			dev_info(&udev->dev, "LPM exit latency is zeroed, disabling LPM.\n");
 195		else
 196			dev_info(&udev->dev, "We don't know the algorithms for LPM for this host, disabling LPM.\n");
 197		return 0;
 198	}
 199
 200	if (!udev->parent || udev->parent->lpm_capable)
 201		return 1;
 202	return 0;
 203}
 204
 205/*
 206 * Set the Maximum Exit Latency (MEL) for the host to wakup up the path from
 207 * U1/U2, send a PING to the device and receive a PING_RESPONSE.
 208 * See USB 3.1 section C.1.5.2
 209 */
 210static void usb_set_lpm_mel(struct usb_device *udev,
 211		struct usb3_lpm_parameters *udev_lpm_params,
 212		unsigned int udev_exit_latency,
 213		struct usb_hub *hub,
 214		struct usb3_lpm_parameters *hub_lpm_params,
 215		unsigned int hub_exit_latency)
 216{
 217	unsigned int total_mel;
 218
 219	/*
 220	 * tMEL1. time to transition path from host to device into U0.
 221	 * MEL for parent already contains the delay up to parent, so only add
 222	 * the exit latency for the last link (pick the slower exit latency),
 223	 * and the hub header decode latency. See USB 3.1 section C 2.2.1
 224	 * Store MEL in nanoseconds
 225	 */
 226	total_mel = hub_lpm_params->mel +
 227		max(udev_exit_latency, hub_exit_latency) * 1000 +
 228		hub->descriptor->u.ss.bHubHdrDecLat * 100;
 229
 230	/*
 231	 * tMEL2. Time to submit PING packet. Sum of tTPTransmissionDelay for
 232	 * each link + wHubDelay for each hub. Add only for last link.
 233	 * tMEL4, the time for PING_RESPONSE to traverse upstream is similar.
 234	 * Multiply by 2 to include it as well.
 235	 */
 236	total_mel += (__le16_to_cpu(hub->descriptor->u.ss.wHubDelay) +
 237		      USB_TP_TRANSMISSION_DELAY) * 2;
 238
 239	/*
 240	 * tMEL3, tPingResponse. Time taken by device to generate PING_RESPONSE
 241	 * after receiving PING. Also add 2100ns as stated in USB 3.1 C 1.5.2.4
 242	 * to cover the delay if the PING_RESPONSE is queued behind a Max Packet
 243	 * Size DP.
 244	 * Note these delays should be added only once for the entire path, so
 245	 * add them to the MEL of the device connected to the roothub.
 246	 */
 247	if (!hub->hdev->parent)
 248		total_mel += USB_PING_RESPONSE_TIME + 2100;
 249
 250	udev_lpm_params->mel = total_mel;
 251}
 252
 253/*
 254 * Set the maximum Device to Host Exit Latency (PEL) for the device to initiate
 255 * a transition from either U1 or U2.
 256 */
 257static void usb_set_lpm_pel(struct usb_device *udev,
 258		struct usb3_lpm_parameters *udev_lpm_params,
 259		unsigned int udev_exit_latency,
 260		struct usb_hub *hub,
 261		struct usb3_lpm_parameters *hub_lpm_params,
 262		unsigned int hub_exit_latency,
 263		unsigned int port_to_port_exit_latency)
 264{
 265	unsigned int first_link_pel;
 266	unsigned int hub_pel;
 267
 268	/*
 269	 * First, the device sends an LFPS to transition the link between the
 270	 * device and the parent hub into U0.  The exit latency is the bigger of
 271	 * the device exit latency or the hub exit latency.
 272	 */
 273	if (udev_exit_latency > hub_exit_latency)
 274		first_link_pel = udev_exit_latency * 1000;
 275	else
 276		first_link_pel = hub_exit_latency * 1000;
 277
 278	/*
 279	 * When the hub starts to receive the LFPS, there is a slight delay for
 280	 * it to figure out that one of the ports is sending an LFPS.  Then it
 281	 * will forward the LFPS to its upstream link.  The exit latency is the
 282	 * delay, plus the PEL that we calculated for this hub.
 283	 */
 284	hub_pel = port_to_port_exit_latency * 1000 + hub_lpm_params->pel;
 285
 286	/*
 287	 * According to figure C-7 in the USB 3.0 spec, the PEL for this device
 288	 * is the greater of the two exit latencies.
 289	 */
 290	if (first_link_pel > hub_pel)
 291		udev_lpm_params->pel = first_link_pel;
 292	else
 293		udev_lpm_params->pel = hub_pel;
 294}
 295
 296/*
 297 * Set the System Exit Latency (SEL) to indicate the total worst-case time from
 298 * when a device initiates a transition to U0, until when it will receive the
 299 * first packet from the host controller.
 300 *
 301 * Section C.1.5.1 describes the four components to this:
 302 *  - t1: device PEL
 303 *  - t2: time for the ERDY to make it from the device to the host.
 304 *  - t3: a host-specific delay to process the ERDY.
 305 *  - t4: time for the packet to make it from the host to the device.
 306 *
 307 * t3 is specific to both the xHCI host and the platform the host is integrated
 308 * into.  The Intel HW folks have said it's negligible, FIXME if a different
 309 * vendor says otherwise.
 310 */
 311static void usb_set_lpm_sel(struct usb_device *udev,
 312		struct usb3_lpm_parameters *udev_lpm_params)
 313{
 314	struct usb_device *parent;
 315	unsigned int num_hubs;
 316	unsigned int total_sel;
 317
 318	/* t1 = device PEL */
 319	total_sel = udev_lpm_params->pel;
 320	/* How many external hubs are in between the device & the root port. */
 321	for (parent = udev->parent, num_hubs = 0; parent->parent;
 322			parent = parent->parent)
 323		num_hubs++;
 324	/* t2 = 2.1us + 250ns * (num_hubs - 1) */
 325	if (num_hubs > 0)
 326		total_sel += 2100 + 250 * (num_hubs - 1);
 327
 328	/* t4 = 250ns * num_hubs */
 329	total_sel += 250 * num_hubs;
 330
 331	udev_lpm_params->sel = total_sel;
 332}
 333
 334static void usb_set_lpm_parameters(struct usb_device *udev)
 335{
 336	struct usb_hub *hub;
 337	unsigned int port_to_port_delay;
 338	unsigned int udev_u1_del;
 339	unsigned int udev_u2_del;
 340	unsigned int hub_u1_del;
 341	unsigned int hub_u2_del;
 342
 343	if (!udev->lpm_capable || udev->speed < USB_SPEED_SUPER)
 344		return;
 345
 346	/* Skip if the device BOS descriptor couldn't be read */
 347	if (!udev->bos)
 348		return;
 349
 350	hub = usb_hub_to_struct_hub(udev->parent);
 351	/* It doesn't take time to transition the roothub into U0, since it
 352	 * doesn't have an upstream link.
 353	 */
 354	if (!hub)
 355		return;
 356
 357	udev_u1_del = udev->bos->ss_cap->bU1devExitLat;
 358	udev_u2_del = le16_to_cpu(udev->bos->ss_cap->bU2DevExitLat);
 359	hub_u1_del = udev->parent->bos->ss_cap->bU1devExitLat;
 360	hub_u2_del = le16_to_cpu(udev->parent->bos->ss_cap->bU2DevExitLat);
 361
 362	usb_set_lpm_mel(udev, &udev->u1_params, udev_u1_del,
 363			hub, &udev->parent->u1_params, hub_u1_del);
 364
 365	usb_set_lpm_mel(udev, &udev->u2_params, udev_u2_del,
 366			hub, &udev->parent->u2_params, hub_u2_del);
 367
 368	/*
 369	 * Appendix C, section C.2.2.2, says that there is a slight delay from
 370	 * when the parent hub notices the downstream port is trying to
 371	 * transition to U0 to when the hub initiates a U0 transition on its
 372	 * upstream port.  The section says the delays are tPort2PortU1EL and
 373	 * tPort2PortU2EL, but it doesn't define what they are.
 374	 *
 375	 * The hub chapter, sections 10.4.2.4 and 10.4.2.5 seem to be talking
 376	 * about the same delays.  Use the maximum delay calculations from those
 377	 * sections.  For U1, it's tHubPort2PortExitLat, which is 1us max.  For
 378	 * U2, it's tHubPort2PortExitLat + U2DevExitLat - U1DevExitLat.  I
 379	 * assume the device exit latencies they are talking about are the hub
 380	 * exit latencies.
 381	 *
 382	 * What do we do if the U2 exit latency is less than the U1 exit
 383	 * latency?  It's possible, although not likely...
 384	 */
 385	port_to_port_delay = 1;
 386
 387	usb_set_lpm_pel(udev, &udev->u1_params, udev_u1_del,
 388			hub, &udev->parent->u1_params, hub_u1_del,
 389			port_to_port_delay);
 390
 391	if (hub_u2_del > hub_u1_del)
 392		port_to_port_delay = 1 + hub_u2_del - hub_u1_del;
 393	else
 394		port_to_port_delay = 1 + hub_u1_del;
 395
 396	usb_set_lpm_pel(udev, &udev->u2_params, udev_u2_del,
 397			hub, &udev->parent->u2_params, hub_u2_del,
 398			port_to_port_delay);
 399
 400	/* Now that we've got PEL, calculate SEL. */
 401	usb_set_lpm_sel(udev, &udev->u1_params);
 402	usb_set_lpm_sel(udev, &udev->u2_params);
 403}
 404
 405/* USB 2.0 spec Section 11.24.4.5 */
 406static int get_hub_descriptor(struct usb_device *hdev,
 407		struct usb_hub_descriptor *desc)
 408{
 409	int i, ret, size;
 410	unsigned dtype;
 411
 412	if (hub_is_superspeed(hdev)) {
 413		dtype = USB_DT_SS_HUB;
 414		size = USB_DT_SS_HUB_SIZE;
 415	} else {
 416		dtype = USB_DT_HUB;
 417		size = sizeof(struct usb_hub_descriptor);
 418	}
 419
 420	for (i = 0; i < 3; i++) {
 421		ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 422			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
 423			dtype << 8, 0, desc, size,
 424			USB_CTRL_GET_TIMEOUT);
 425		if (hub_is_superspeed(hdev)) {
 426			if (ret == size)
 427				return ret;
 428		} else if (ret >= USB_DT_HUB_NONVAR_SIZE + 2) {
 429			/* Make sure we have the DeviceRemovable field. */
 430			size = USB_DT_HUB_NONVAR_SIZE + desc->bNbrPorts / 8 + 1;
 431			if (ret < size)
 432				return -EMSGSIZE;
 433			return ret;
 434		}
 435	}
 436	return -EINVAL;
 437}
 438
 439/*
 440 * USB 2.0 spec Section 11.24.2.1
 441 */
 442static int clear_hub_feature(struct usb_device *hdev, int feature)
 443{
 444	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 445		USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
 446}
 447
 448/*
 449 * USB 2.0 spec Section 11.24.2.2
 450 */
 451int usb_clear_port_feature(struct usb_device *hdev, int port1, int feature)
 452{
 453	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 454		USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
 455		NULL, 0, 1000);
 456}
 457
 458/*
 459 * USB 2.0 spec Section 11.24.2.13
 460 */
 461static int set_port_feature(struct usb_device *hdev, int port1, int feature)
 462{
 463	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 464		USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
 465		NULL, 0, 1000);
 466}
 467
 468static char *to_led_name(int selector)
 469{
 470	switch (selector) {
 471	case HUB_LED_AMBER:
 472		return "amber";
 473	case HUB_LED_GREEN:
 474		return "green";
 475	case HUB_LED_OFF:
 476		return "off";
 477	case HUB_LED_AUTO:
 478		return "auto";
 479	default:
 480		return "??";
 481	}
 482}
 483
 484/*
 485 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
 486 * for info about using port indicators
 487 */
 488static void set_port_led(struct usb_hub *hub, int port1, int selector)
 489{
 490	struct usb_port *port_dev = hub->ports[port1 - 1];
 491	int status;
 492
 493	status = set_port_feature(hub->hdev, (selector << 8) | port1,
 494			USB_PORT_FEAT_INDICATOR);
 495	dev_dbg(&port_dev->dev, "indicator %s status %d\n",
 496		to_led_name(selector), status);
 497}
 498
 499#define	LED_CYCLE_PERIOD	((2*HZ)/3)
 500
 501static void led_work(struct work_struct *work)
 502{
 503	struct usb_hub		*hub =
 504		container_of(work, struct usb_hub, leds.work);
 505	struct usb_device	*hdev = hub->hdev;
 506	unsigned		i;
 507	unsigned		changed = 0;
 508	int			cursor = -1;
 509
 510	if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
 511		return;
 512
 513	for (i = 0; i < hdev->maxchild; i++) {
 514		unsigned	selector, mode;
 515
 516		/* 30%-50% duty cycle */
 517
 518		switch (hub->indicator[i]) {
 519		/* cycle marker */
 520		case INDICATOR_CYCLE:
 521			cursor = i;
 522			selector = HUB_LED_AUTO;
 523			mode = INDICATOR_AUTO;
 524			break;
 525		/* blinking green = sw attention */
 526		case INDICATOR_GREEN_BLINK:
 527			selector = HUB_LED_GREEN;
 528			mode = INDICATOR_GREEN_BLINK_OFF;
 529			break;
 530		case INDICATOR_GREEN_BLINK_OFF:
 531			selector = HUB_LED_OFF;
 532			mode = INDICATOR_GREEN_BLINK;
 533			break;
 534		/* blinking amber = hw attention */
 535		case INDICATOR_AMBER_BLINK:
 536			selector = HUB_LED_AMBER;
 537			mode = INDICATOR_AMBER_BLINK_OFF;
 538			break;
 539		case INDICATOR_AMBER_BLINK_OFF:
 540			selector = HUB_LED_OFF;
 541			mode = INDICATOR_AMBER_BLINK;
 542			break;
 543		/* blink green/amber = reserved */
 544		case INDICATOR_ALT_BLINK:
 545			selector = HUB_LED_GREEN;
 546			mode = INDICATOR_ALT_BLINK_OFF;
 547			break;
 548		case INDICATOR_ALT_BLINK_OFF:
 549			selector = HUB_LED_AMBER;
 550			mode = INDICATOR_ALT_BLINK;
 551			break;
 552		default:
 553			continue;
 554		}
 555		if (selector != HUB_LED_AUTO)
 556			changed = 1;
 557		set_port_led(hub, i + 1, selector);
 558		hub->indicator[i] = mode;
 559	}
 560	if (!changed && blinkenlights) {
 561		cursor++;
 562		cursor %= hdev->maxchild;
 563		set_port_led(hub, cursor + 1, HUB_LED_GREEN);
 564		hub->indicator[cursor] = INDICATOR_CYCLE;
 565		changed++;
 566	}
 567	if (changed)
 568		queue_delayed_work(system_power_efficient_wq,
 569				&hub->leds, LED_CYCLE_PERIOD);
 570}
 571
 572/* use a short timeout for hub/port status fetches */
 573#define	USB_STS_TIMEOUT		1000
 574#define	USB_STS_RETRIES		5
 575
 576/*
 577 * USB 2.0 spec Section 11.24.2.6
 578 */
 579static int get_hub_status(struct usb_device *hdev,
 580		struct usb_hub_status *data)
 581{
 582	int i, status = -ETIMEDOUT;
 583
 584	for (i = 0; i < USB_STS_RETRIES &&
 585			(status == -ETIMEDOUT || status == -EPIPE); i++) {
 586		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 587			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
 588			data, sizeof(*data), USB_STS_TIMEOUT);
 589	}
 590	return status;
 591}
 592
 593/*
 594 * USB 2.0 spec Section 11.24.2.7
 595 * USB 3.1 takes into use the wValue and wLength fields, spec Section 10.16.2.6
 596 */
 597static int get_port_status(struct usb_device *hdev, int port1,
 598			   void *data, u16 value, u16 length)
 599{
 600	int i, status = -ETIMEDOUT;
 601
 602	for (i = 0; i < USB_STS_RETRIES &&
 603			(status == -ETIMEDOUT || status == -EPIPE); i++) {
 604		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 605			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, value,
 606			port1, data, length, USB_STS_TIMEOUT);
 607	}
 608	return status;
 609}
 610
 611static int hub_ext_port_status(struct usb_hub *hub, int port1, int type,
 612			       u16 *status, u16 *change, u32 *ext_status)
 613{
 614	int ret;
 615	int len = 4;
 616
 617	if (type != HUB_PORT_STATUS)
 618		len = 8;
 619
 620	mutex_lock(&hub->status_mutex);
 621	ret = get_port_status(hub->hdev, port1, &hub->status->port, type, len);
 622	if (ret < len) {
 623		if (ret != -ENODEV)
 624			dev_err(hub->intfdev,
 625				"%s failed (err = %d)\n", __func__, ret);
 626		if (ret >= 0)
 627			ret = -EIO;
 628	} else {
 629		*status = le16_to_cpu(hub->status->port.wPortStatus);
 630		*change = le16_to_cpu(hub->status->port.wPortChange);
 631		if (type != HUB_PORT_STATUS && ext_status)
 632			*ext_status = le32_to_cpu(
 633				hub->status->port.dwExtPortStatus);
 634		ret = 0;
 635	}
 636	mutex_unlock(&hub->status_mutex);
 637
 638	/*
 639	 * There is no need to lock status_mutex here, because status_mutex
 640	 * protects hub->status, and the phy driver only checks the port
 641	 * status without changing the status.
 642	 */
 643	if (!ret) {
 644		struct usb_device *hdev = hub->hdev;
 645
 646		/*
 647		 * Only roothub will be notified of connection changes,
 648		 * since the USB PHY only cares about changes at the next
 649		 * level.
 650		 */
 651		if (is_root_hub(hdev)) {
 652			struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
 653			bool connect;
 654			bool connect_change;
 655
 656			connect_change = *change & USB_PORT_STAT_C_CONNECTION;
 657			connect = *status & USB_PORT_STAT_CONNECTION;
 658			if (connect_change && connect)
 659				usb_phy_roothub_notify_connect(hcd->phy_roothub, port1 - 1);
 660			else if (connect_change)
 661				usb_phy_roothub_notify_disconnect(hcd->phy_roothub, port1 - 1);
 662		}
 663	}
 664
 665	return ret;
 666}
 667
 668int usb_hub_port_status(struct usb_hub *hub, int port1,
 669		u16 *status, u16 *change)
 670{
 671	return hub_ext_port_status(hub, port1, HUB_PORT_STATUS,
 672				   status, change, NULL);
 673}
 674
 675static void hub_resubmit_irq_urb(struct usb_hub *hub)
 676{
 677	unsigned long flags;
 678	int status;
 679
 680	spin_lock_irqsave(&hub->irq_urb_lock, flags);
 681
 682	if (hub->quiescing) {
 683		spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
 684		return;
 685	}
 686
 687	status = usb_submit_urb(hub->urb, GFP_ATOMIC);
 688	if (status && status != -ENODEV && status != -EPERM &&
 689	    status != -ESHUTDOWN) {
 690		dev_err(hub->intfdev, "resubmit --> %d\n", status);
 691		mod_timer(&hub->irq_urb_retry, jiffies + HZ);
 692	}
 693
 694	spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
 695}
 696
 697static void hub_retry_irq_urb(struct timer_list *t)
 698{
 699	struct usb_hub *hub = from_timer(hub, t, irq_urb_retry);
 700
 701	hub_resubmit_irq_urb(hub);
 702}
 703
 704
 705static void kick_hub_wq(struct usb_hub *hub)
 706{
 707	struct usb_interface *intf;
 708
 709	if (hub->disconnected || work_pending(&hub->events))
 710		return;
 711
 712	/*
 713	 * Suppress autosuspend until the event is proceed.
 714	 *
 715	 * Be careful and make sure that the symmetric operation is
 716	 * always called. We are here only when there is no pending
 717	 * work for this hub. Therefore put the interface either when
 718	 * the new work is called or when it is canceled.
 719	 */
 720	intf = to_usb_interface(hub->intfdev);
 721	usb_autopm_get_interface_no_resume(intf);
 722	hub_get(hub);
 723
 724	if (queue_work(hub_wq, &hub->events))
 725		return;
 726
 727	/* the work has already been scheduled */
 728	usb_autopm_put_interface_async(intf);
 729	hub_put(hub);
 730}
 731
 732void usb_kick_hub_wq(struct usb_device *hdev)
 733{
 734	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
 735
 736	if (hub)
 737		kick_hub_wq(hub);
 738}
 739
 740/*
 741 * Let the USB core know that a USB 3.0 device has sent a Function Wake Device
 742 * Notification, which indicates it had initiated remote wakeup.
 743 *
 744 * USB 3.0 hubs do not report the port link state change from U3 to U0 when the
 745 * device initiates resume, so the USB core will not receive notice of the
 746 * resume through the normal hub interrupt URB.
 747 */
 748void usb_wakeup_notification(struct usb_device *hdev,
 749		unsigned int portnum)
 750{
 751	struct usb_hub *hub;
 752	struct usb_port *port_dev;
 753
 754	if (!hdev)
 755		return;
 756
 757	hub = usb_hub_to_struct_hub(hdev);
 758	if (hub) {
 759		port_dev = hub->ports[portnum - 1];
 760		if (port_dev && port_dev->child)
 761			pm_wakeup_event(&port_dev->child->dev, 0);
 762
 763		set_bit(portnum, hub->wakeup_bits);
 764		kick_hub_wq(hub);
 765	}
 766}
 767EXPORT_SYMBOL_GPL(usb_wakeup_notification);
 768
 769/* completion function, fires on port status changes and various faults */
 770static void hub_irq(struct urb *urb)
 771{
 772	struct usb_hub *hub = urb->context;
 773	int status = urb->status;
 774	unsigned i;
 775	unsigned long bits;
 776
 777	switch (status) {
 778	case -ENOENT:		/* synchronous unlink */
 779	case -ECONNRESET:	/* async unlink */
 780	case -ESHUTDOWN:	/* hardware going away */
 781		return;
 782
 783	default:		/* presumably an error */
 784		/* Cause a hub reset after 10 consecutive errors */
 785		dev_dbg(hub->intfdev, "transfer --> %d\n", status);
 786		if ((++hub->nerrors < 10) || hub->error)
 787			goto resubmit;
 788		hub->error = status;
 789		fallthrough;
 790
 791	/* let hub_wq handle things */
 792	case 0:			/* we got data:  port status changed */
 793		bits = 0;
 794		for (i = 0; i < urb->actual_length; ++i)
 795			bits |= ((unsigned long) ((*hub->buffer)[i]))
 796					<< (i*8);
 797		hub->event_bits[0] = bits;
 798		break;
 799	}
 800
 801	hub->nerrors = 0;
 802
 803	/* Something happened, let hub_wq figure it out */
 804	kick_hub_wq(hub);
 805
 806resubmit:
 807	hub_resubmit_irq_urb(hub);
 808}
 809
 810/* USB 2.0 spec Section 11.24.2.3 */
 811static inline int
 812hub_clear_tt_buffer(struct usb_device *hdev, u16 devinfo, u16 tt)
 813{
 814	/* Need to clear both directions for control ep */
 815	if (((devinfo >> 11) & USB_ENDPOINT_XFERTYPE_MASK) ==
 816			USB_ENDPOINT_XFER_CONTROL) {
 817		int status = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 818				HUB_CLEAR_TT_BUFFER, USB_RT_PORT,
 819				devinfo ^ 0x8000, tt, NULL, 0, 1000);
 820		if (status)
 821			return status;
 822	}
 823	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 824			       HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
 825			       tt, NULL, 0, 1000);
 826}
 827
 828/*
 829 * enumeration blocks hub_wq for a long time. we use keventd instead, since
 830 * long blocking there is the exception, not the rule.  accordingly, HCDs
 831 * talking to TTs must queue control transfers (not just bulk and iso), so
 832 * both can talk to the same hub concurrently.
 833 */
 834static void hub_tt_work(struct work_struct *work)
 835{
 836	struct usb_hub		*hub =
 837		container_of(work, struct usb_hub, tt.clear_work);
 838	unsigned long		flags;
 839
 840	spin_lock_irqsave(&hub->tt.lock, flags);
 841	while (!list_empty(&hub->tt.clear_list)) {
 842		struct list_head	*next;
 843		struct usb_tt_clear	*clear;
 844		struct usb_device	*hdev = hub->hdev;
 845		const struct hc_driver	*drv;
 846		int			status;
 847
 848		next = hub->tt.clear_list.next;
 849		clear = list_entry(next, struct usb_tt_clear, clear_list);
 850		list_del(&clear->clear_list);
 851
 852		/* drop lock so HCD can concurrently report other TT errors */
 853		spin_unlock_irqrestore(&hub->tt.lock, flags);
 854		status = hub_clear_tt_buffer(hdev, clear->devinfo, clear->tt);
 855		if (status && status != -ENODEV)
 856			dev_err(&hdev->dev,
 857				"clear tt %d (%04x) error %d\n",
 858				clear->tt, clear->devinfo, status);
 859
 860		/* Tell the HCD, even if the operation failed */
 861		drv = clear->hcd->driver;
 862		if (drv->clear_tt_buffer_complete)
 863			(drv->clear_tt_buffer_complete)(clear->hcd, clear->ep);
 864
 865		kfree(clear);
 866		spin_lock_irqsave(&hub->tt.lock, flags);
 867	}
 868	spin_unlock_irqrestore(&hub->tt.lock, flags);
 869}
 870
 871/**
 872 * usb_hub_set_port_power - control hub port's power state
 873 * @hdev: USB device belonging to the usb hub
 874 * @hub: target hub
 875 * @port1: port index
 876 * @set: expected status
 877 *
 878 * call this function to control port's power via setting or
 879 * clearing the port's PORT_POWER feature.
 880 *
 881 * Return: 0 if successful. A negative error code otherwise.
 882 */
 883int usb_hub_set_port_power(struct usb_device *hdev, struct usb_hub *hub,
 884			   int port1, bool set)
 885{
 886	int ret;
 887
 888	if (set)
 889		ret = set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
 890	else
 891		ret = usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
 892
 893	if (ret)
 894		return ret;
 895
 896	if (set)
 897		set_bit(port1, hub->power_bits);
 898	else
 899		clear_bit(port1, hub->power_bits);
 900	return 0;
 901}
 902
 903/**
 904 * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
 905 * @urb: an URB associated with the failed or incomplete split transaction
 906 *
 907 * High speed HCDs use this to tell the hub driver that some split control or
 908 * bulk transaction failed in a way that requires clearing internal state of
 909 * a transaction translator.  This is normally detected (and reported) from
 910 * interrupt context.
 911 *
 912 * It may not be possible for that hub to handle additional full (or low)
 913 * speed transactions until that state is fully cleared out.
 914 *
 915 * Return: 0 if successful. A negative error code otherwise.
 916 */
 917int usb_hub_clear_tt_buffer(struct urb *urb)
 918{
 919	struct usb_device	*udev = urb->dev;
 920	int			pipe = urb->pipe;
 921	struct usb_tt		*tt = udev->tt;
 922	unsigned long		flags;
 923	struct usb_tt_clear	*clear;
 924
 925	/* we've got to cope with an arbitrary number of pending TT clears,
 926	 * since each TT has "at least two" buffers that can need it (and
 927	 * there can be many TTs per hub).  even if they're uncommon.
 928	 */
 929	clear = kmalloc(sizeof *clear, GFP_ATOMIC);
 930	if (clear == NULL) {
 931		dev_err(&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
 932		/* FIXME recover somehow ... RESET_TT? */
 933		return -ENOMEM;
 934	}
 935
 936	/* info that CLEAR_TT_BUFFER needs */
 937	clear->tt = tt->multi ? udev->ttport : 1;
 938	clear->devinfo = usb_pipeendpoint (pipe);
 939	clear->devinfo |= ((u16)udev->devaddr) << 4;
 940	clear->devinfo |= usb_pipecontrol(pipe)
 941			? (USB_ENDPOINT_XFER_CONTROL << 11)
 942			: (USB_ENDPOINT_XFER_BULK << 11);
 943	if (usb_pipein(pipe))
 944		clear->devinfo |= 1 << 15;
 945
 946	/* info for completion callback */
 947	clear->hcd = bus_to_hcd(udev->bus);
 948	clear->ep = urb->ep;
 949
 950	/* tell keventd to clear state for this TT */
 951	spin_lock_irqsave(&tt->lock, flags);
 952	list_add_tail(&clear->clear_list, &tt->clear_list);
 953	schedule_work(&tt->clear_work);
 954	spin_unlock_irqrestore(&tt->lock, flags);
 955	return 0;
 956}
 957EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer);
 958
 959static void hub_power_on(struct usb_hub *hub, bool do_delay)
 960{
 961	int port1;
 962
 963	/* Enable power on each port.  Some hubs have reserved values
 964	 * of LPSM (> 2) in their descriptors, even though they are
 965	 * USB 2.0 hubs.  Some hubs do not implement port-power switching
 966	 * but only emulate it.  In all cases, the ports won't work
 967	 * unless we send these messages to the hub.
 968	 */
 969	if (hub_is_port_power_switchable(hub))
 970		dev_dbg(hub->intfdev, "enabling power on all ports\n");
 971	else
 972		dev_dbg(hub->intfdev, "trying to enable port power on "
 973				"non-switchable hub\n");
 974	for (port1 = 1; port1 <= hub->hdev->maxchild; port1++)
 975		if (test_bit(port1, hub->power_bits))
 976			set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
 977		else
 978			usb_clear_port_feature(hub->hdev, port1,
 979						USB_PORT_FEAT_POWER);
 980	if (do_delay)
 981		msleep(hub_power_on_good_delay(hub));
 982}
 983
 984static int hub_hub_status(struct usb_hub *hub,
 985		u16 *status, u16 *change)
 986{
 987	int ret;
 988
 989	mutex_lock(&hub->status_mutex);
 990	ret = get_hub_status(hub->hdev, &hub->status->hub);
 991	if (ret < 0) {
 992		if (ret != -ENODEV)
 993			dev_err(hub->intfdev,
 994				"%s failed (err = %d)\n", __func__, ret);
 995	} else {
 996		*status = le16_to_cpu(hub->status->hub.wHubStatus);
 997		*change = le16_to_cpu(hub->status->hub.wHubChange);
 998		ret = 0;
 999	}
1000	mutex_unlock(&hub->status_mutex);
1001	return ret;
1002}
1003
1004static int hub_set_port_link_state(struct usb_hub *hub, int port1,
1005			unsigned int link_status)
1006{
1007	return set_port_feature(hub->hdev,
1008			port1 | (link_status << 3),
1009			USB_PORT_FEAT_LINK_STATE);
1010}
1011
1012/*
1013 * Disable a port and mark a logical connect-change event, so that some
1014 * time later hub_wq will disconnect() any existing usb_device on the port
1015 * and will re-enumerate if there actually is a device attached.
1016 */
1017static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1018{
1019	dev_dbg(&hub->ports[port1 - 1]->dev, "logical disconnect\n");
1020	hub_port_disable(hub, port1, 1);
1021
1022	/* FIXME let caller ask to power down the port:
1023	 *  - some devices won't enumerate without a VBUS power cycle
1024	 *  - SRP saves power that way
1025	 *  - ... new call, TBD ...
1026	 * That's easy if this hub can switch power per-port, and
1027	 * hub_wq reactivates the port later (timer, SRP, etc).
1028	 * Powerdown must be optional, because of reset/DFU.
1029	 */
1030
1031	set_bit(port1, hub->change_bits);
1032	kick_hub_wq(hub);
1033}
1034
1035/**
1036 * usb_remove_device - disable a device's port on its parent hub
1037 * @udev: device to be disabled and removed
1038 * Context: @udev locked, must be able to sleep.
1039 *
1040 * After @udev's port has been disabled, hub_wq is notified and it will
1041 * see that the device has been disconnected.  When the device is
1042 * physically unplugged and something is plugged in, the events will
1043 * be received and processed normally.
1044 *
1045 * Return: 0 if successful. A negative error code otherwise.
1046 */
1047int usb_remove_device(struct usb_device *udev)
1048{
1049	struct usb_hub *hub;
1050	struct usb_interface *intf;
1051	int ret;
1052
1053	if (!udev->parent)	/* Can't remove a root hub */
1054		return -EINVAL;
1055	hub = usb_hub_to_struct_hub(udev->parent);
1056	intf = to_usb_interface(hub->intfdev);
1057
1058	ret = usb_autopm_get_interface(intf);
1059	if (ret < 0)
1060		return ret;
1061
1062	set_bit(udev->portnum, hub->removed_bits);
1063	hub_port_logical_disconnect(hub, udev->portnum);
1064	usb_autopm_put_interface(intf);
1065	return 0;
1066}
1067
1068enum hub_activation_type {
1069	HUB_INIT, HUB_INIT2, HUB_INIT3,		/* INITs must come first */
1070	HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
1071};
1072
1073static void hub_init_func2(struct work_struct *ws);
1074static void hub_init_func3(struct work_struct *ws);
1075
1076static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
1077{
1078	struct usb_device *hdev = hub->hdev;
1079	struct usb_hcd *hcd;
1080	int ret;
1081	int port1;
1082	int status;
1083	bool need_debounce_delay = false;
1084	unsigned delay;
1085
1086	/* Continue a partial initialization */
1087	if (type == HUB_INIT2 || type == HUB_INIT3) {
1088		device_lock(&hdev->dev);
1089
1090		/* Was the hub disconnected while we were waiting? */
1091		if (hub->disconnected)
1092			goto disconnected;
1093		if (type == HUB_INIT2)
1094			goto init2;
1095		goto init3;
1096	}
1097	hub_get(hub);
1098
1099	/* The superspeed hub except for root hub has to use Hub Depth
1100	 * value as an offset into the route string to locate the bits
1101	 * it uses to determine the downstream port number. So hub driver
1102	 * should send a set hub depth request to superspeed hub after
1103	 * the superspeed hub is set configuration in initialization or
1104	 * reset procedure.
1105	 *
1106	 * After a resume, port power should still be on.
1107	 * For any other type of activation, turn it on.
1108	 */
1109	if (type != HUB_RESUME) {
1110		if (hdev->parent && hub_is_superspeed(hdev)) {
1111			ret = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
1112					HUB_SET_DEPTH, USB_RT_HUB,
1113					hdev->level - 1, 0, NULL, 0,
1114					USB_CTRL_SET_TIMEOUT);
1115			if (ret < 0)
1116				dev_err(hub->intfdev,
1117						"set hub depth failed\n");
1118		}
1119
1120		/* Speed up system boot by using a delayed_work for the
1121		 * hub's initial power-up delays.  This is pretty awkward
1122		 * and the implementation looks like a home-brewed sort of
1123		 * setjmp/longjmp, but it saves at least 100 ms for each
1124		 * root hub (assuming usbcore is compiled into the kernel
1125		 * rather than as a module).  It adds up.
1126		 *
1127		 * This can't be done for HUB_RESUME or HUB_RESET_RESUME
1128		 * because for those activation types the ports have to be
1129		 * operational when we return.  In theory this could be done
1130		 * for HUB_POST_RESET, but it's easier not to.
1131		 */
1132		if (type == HUB_INIT) {
1133			delay = hub_power_on_good_delay(hub);
1134
1135			hub_power_on(hub, false);
1136			INIT_DELAYED_WORK(&hub->init_work, hub_init_func2);
1137			queue_delayed_work(system_power_efficient_wq,
1138					&hub->init_work,
1139					msecs_to_jiffies(delay));
1140
1141			/* Suppress autosuspend until init is done */
1142			usb_autopm_get_interface_no_resume(
1143					to_usb_interface(hub->intfdev));
1144			return;		/* Continues at init2: below */
1145		} else if (type == HUB_RESET_RESUME) {
1146			/* The internal host controller state for the hub device
1147			 * may be gone after a host power loss on system resume.
1148			 * Update the device's info so the HW knows it's a hub.
1149			 */
1150			hcd = bus_to_hcd(hdev->bus);
1151			if (hcd->driver->update_hub_device) {
1152				ret = hcd->driver->update_hub_device(hcd, hdev,
1153						&hub->tt, GFP_NOIO);
1154				if (ret < 0) {
1155					dev_err(hub->intfdev,
1156						"Host not accepting hub info update\n");
1157					dev_err(hub->intfdev,
1158						"LS/FS devices and hubs may not work under this hub\n");
1159				}
1160			}
1161			hub_power_on(hub, true);
1162		} else {
1163			hub_power_on(hub, true);
1164		}
1165	/* Give some time on remote wakeup to let links to transit to U0 */
1166	} else if (hub_is_superspeed(hub->hdev))
1167		msleep(20);
1168
1169 init2:
1170
1171	/*
1172	 * Check each port and set hub->change_bits to let hub_wq know
1173	 * which ports need attention.
1174	 */
1175	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
1176		struct usb_port *port_dev = hub->ports[port1 - 1];
1177		struct usb_device *udev = port_dev->child;
1178		u16 portstatus, portchange;
1179
1180		portstatus = portchange = 0;
1181		status = usb_hub_port_status(hub, port1, &portstatus, &portchange);
1182		if (status)
1183			goto abort;
1184
1185		if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
1186			dev_dbg(&port_dev->dev, "status %04x change %04x\n",
1187					portstatus, portchange);
1188
1189		/*
1190		 * After anything other than HUB_RESUME (i.e., initialization
1191		 * or any sort of reset), every port should be disabled.
1192		 * Unconnected ports should likewise be disabled (paranoia),
1193		 * and so should ports for which we have no usb_device.
1194		 */
1195		if ((portstatus & USB_PORT_STAT_ENABLE) && (
1196				type != HUB_RESUME ||
1197				!(portstatus & USB_PORT_STAT_CONNECTION) ||
1198				!udev ||
1199				udev->state == USB_STATE_NOTATTACHED)) {
1200			/*
1201			 * USB3 protocol ports will automatically transition
1202			 * to Enabled state when detect an USB3.0 device attach.
1203			 * Do not disable USB3 protocol ports, just pretend
1204			 * power was lost
1205			 */
1206			portstatus &= ~USB_PORT_STAT_ENABLE;
1207			if (!hub_is_superspeed(hdev))
1208				usb_clear_port_feature(hdev, port1,
1209						   USB_PORT_FEAT_ENABLE);
1210		}
1211
1212		/* Make sure a warm-reset request is handled by port_event */
1213		if (type == HUB_RESUME &&
1214		    hub_port_warm_reset_required(hub, port1, portstatus))
1215			set_bit(port1, hub->event_bits);
1216
1217		/*
1218		 * Add debounce if USB3 link is in polling/link training state.
1219		 * Link will automatically transition to Enabled state after
1220		 * link training completes.
1221		 */
1222		if (hub_is_superspeed(hdev) &&
1223		    ((portstatus & USB_PORT_STAT_LINK_STATE) ==
1224						USB_SS_PORT_LS_POLLING))
1225			need_debounce_delay = true;
1226
1227		/* Clear status-change flags; we'll debounce later */
1228		if (portchange & USB_PORT_STAT_C_CONNECTION) {
1229			need_debounce_delay = true;
1230			usb_clear_port_feature(hub->hdev, port1,
1231					USB_PORT_FEAT_C_CONNECTION);
1232		}
1233		if (portchange & USB_PORT_STAT_C_ENABLE) {
1234			need_debounce_delay = true;
1235			usb_clear_port_feature(hub->hdev, port1,
1236					USB_PORT_FEAT_C_ENABLE);
1237		}
1238		if (portchange & USB_PORT_STAT_C_RESET) {
1239			need_debounce_delay = true;
1240			usb_clear_port_feature(hub->hdev, port1,
1241					USB_PORT_FEAT_C_RESET);
1242		}
1243		if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
1244				hub_is_superspeed(hub->hdev)) {
1245			need_debounce_delay = true;
1246			usb_clear_port_feature(hub->hdev, port1,
1247					USB_PORT_FEAT_C_BH_PORT_RESET);
1248		}
1249		/* We can forget about a "removed" device when there's a
1250		 * physical disconnect or the connect status changes.
1251		 */
1252		if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
1253				(portchange & USB_PORT_STAT_C_CONNECTION))
1254			clear_bit(port1, hub->removed_bits);
1255
1256		if (!udev || udev->state == USB_STATE_NOTATTACHED) {
1257			/* Tell hub_wq to disconnect the device or
1258			 * check for a new connection or over current condition.
1259			 * Based on USB2.0 Spec Section 11.12.5,
1260			 * C_PORT_OVER_CURRENT could be set while
1261			 * PORT_OVER_CURRENT is not. So check for any of them.
1262			 */
1263			if (udev || (portstatus & USB_PORT_STAT_CONNECTION) ||
1264			    (portchange & USB_PORT_STAT_C_CONNECTION) ||
1265			    (portstatus & USB_PORT_STAT_OVERCURRENT) ||
1266			    (portchange & USB_PORT_STAT_C_OVERCURRENT))
1267				set_bit(port1, hub->change_bits);
1268
1269		} else if (portstatus & USB_PORT_STAT_ENABLE) {
1270			bool port_resumed = (portstatus &
1271					USB_PORT_STAT_LINK_STATE) ==
1272				USB_SS_PORT_LS_U0;
1273			/* The power session apparently survived the resume.
1274			 * If there was an overcurrent or suspend change
1275			 * (i.e., remote wakeup request), have hub_wq
1276			 * take care of it.  Look at the port link state
1277			 * for USB 3.0 hubs, since they don't have a suspend
1278			 * change bit, and they don't set the port link change
1279			 * bit on device-initiated resume.
1280			 */
1281			if (portchange || (hub_is_superspeed(hub->hdev) &&
1282						port_resumed))
1283				set_bit(port1, hub->event_bits);
1284
1285		} else if (udev->persist_enabled) {
1286#ifdef CONFIG_PM
1287			udev->reset_resume = 1;
1288#endif
1289			/* Don't set the change_bits when the device
1290			 * was powered off.
1291			 */
1292			if (test_bit(port1, hub->power_bits))
1293				set_bit(port1, hub->change_bits);
1294
1295		} else {
1296			/* The power session is gone; tell hub_wq */
1297			usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1298			set_bit(port1, hub->change_bits);
1299		}
1300	}
1301
1302	/* If no port-status-change flags were set, we don't need any
1303	 * debouncing.  If flags were set we can try to debounce the
1304	 * ports all at once right now, instead of letting hub_wq do them
1305	 * one at a time later on.
1306	 *
1307	 * If any port-status changes do occur during this delay, hub_wq
1308	 * will see them later and handle them normally.
1309	 */
1310	if (need_debounce_delay) {
1311		delay = HUB_DEBOUNCE_STABLE;
1312
1313		/* Don't do a long sleep inside a workqueue routine */
1314		if (type == HUB_INIT2) {
1315			INIT_DELAYED_WORK(&hub->init_work, hub_init_func3);
1316			queue_delayed_work(system_power_efficient_wq,
1317					&hub->init_work,
1318					msecs_to_jiffies(delay));
1319			device_unlock(&hdev->dev);
1320			return;		/* Continues at init3: below */
1321		} else {
1322			msleep(delay);
1323		}
1324	}
1325 init3:
1326	hub->quiescing = 0;
1327
1328	status = usb_submit_urb(hub->urb, GFP_NOIO);
1329	if (status < 0)
1330		dev_err(hub->intfdev, "activate --> %d\n", status);
1331	if (hub->has_indicators && blinkenlights)
1332		queue_delayed_work(system_power_efficient_wq,
1333				&hub->leds, LED_CYCLE_PERIOD);
1334
1335	/* Scan all ports that need attention */
1336	kick_hub_wq(hub);
1337 abort:
1338	if (type == HUB_INIT2 || type == HUB_INIT3) {
1339		/* Allow autosuspend if it was suppressed */
1340 disconnected:
1341		usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
1342		device_unlock(&hdev->dev);
1343	}
1344
1345	hub_put(hub);
1346}
1347
1348/* Implement the continuations for the delays above */
1349static void hub_init_func2(struct work_struct *ws)
1350{
1351	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1352
1353	hub_activate(hub, HUB_INIT2);
1354}
1355
1356static void hub_init_func3(struct work_struct *ws)
1357{
1358	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1359
1360	hub_activate(hub, HUB_INIT3);
1361}
1362
1363enum hub_quiescing_type {
1364	HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
1365};
1366
1367static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
1368{
1369	struct usb_device *hdev = hub->hdev;
1370	unsigned long flags;
1371	int i;
1372
1373	/* hub_wq and related activity won't re-trigger */
1374	spin_lock_irqsave(&hub->irq_urb_lock, flags);
1375	hub->quiescing = 1;
1376	spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
1377
1378	if (type != HUB_SUSPEND) {
1379		/* Disconnect all the children */
1380		for (i = 0; i < hdev->maxchild; ++i) {
1381			if (hub->ports[i]->child)
1382				usb_disconnect(&hub->ports[i]->child);
1383		}
1384	}
1385
1386	/* Stop hub_wq and related activity */
1387	del_timer_sync(&hub->irq_urb_retry);
1388	usb_kill_urb(hub->urb);
1389	if (hub->has_indicators)
1390		cancel_delayed_work_sync(&hub->leds);
1391	if (hub->tt.hub)
1392		flush_work(&hub->tt.clear_work);
1393}
1394
1395static void hub_pm_barrier_for_all_ports(struct usb_hub *hub)
1396{
1397	int i;
1398
1399	for (i = 0; i < hub->hdev->maxchild; ++i)
1400		pm_runtime_barrier(&hub->ports[i]->dev);
1401}
1402
1403/* caller has locked the hub device */
1404static int hub_pre_reset(struct usb_interface *intf)
1405{
1406	struct usb_hub *hub = usb_get_intfdata(intf);
1407
1408	hub_quiesce(hub, HUB_PRE_RESET);
1409	hub->in_reset = 1;
1410	hub_pm_barrier_for_all_ports(hub);
1411	return 0;
1412}
1413
1414/* caller has locked the hub device */
1415static int hub_post_reset(struct usb_interface *intf)
1416{
1417	struct usb_hub *hub = usb_get_intfdata(intf);
1418
1419	hub->in_reset = 0;
1420	hub_pm_barrier_for_all_ports(hub);
1421	hub_activate(hub, HUB_POST_RESET);
1422	return 0;
1423}
1424
1425static int hub_configure(struct usb_hub *hub,
1426	struct usb_endpoint_descriptor *endpoint)
1427{
1428	struct usb_hcd *hcd;
1429	struct usb_device *hdev = hub->hdev;
1430	struct device *hub_dev = hub->intfdev;
1431	u16 hubstatus, hubchange;
1432	u16 wHubCharacteristics;
1433	unsigned int pipe;
1434	int maxp, ret, i;
1435	char *message = "out of memory";
1436	unsigned unit_load;
1437	unsigned full_load;
1438	unsigned maxchild;
1439
1440	hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
1441	if (!hub->buffer) {
1442		ret = -ENOMEM;
1443		goto fail;
1444	}
1445
1446	hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
1447	if (!hub->status) {
1448		ret = -ENOMEM;
1449		goto fail;
1450	}
1451	mutex_init(&hub->status_mutex);
1452
1453	hub->descriptor = kzalloc(sizeof(*hub->descriptor), GFP_KERNEL);
1454	if (!hub->descriptor) {
1455		ret = -ENOMEM;
1456		goto fail;
1457	}
1458
1459	/* Request the entire hub descriptor.
1460	 * hub->descriptor can handle USB_MAXCHILDREN ports,
1461	 * but a (non-SS) hub can/will return fewer bytes here.
1462	 */
1463	ret = get_hub_descriptor(hdev, hub->descriptor);
1464	if (ret < 0) {
1465		message = "can't read hub descriptor";
1466		goto fail;
1467	}
1468
1469	maxchild = USB_MAXCHILDREN;
1470	if (hub_is_superspeed(hdev))
1471		maxchild = min_t(unsigned, maxchild, USB_SS_MAXPORTS);
1472
1473	if (hub->descriptor->bNbrPorts > maxchild) {
1474		message = "hub has too many ports!";
1475		ret = -ENODEV;
1476		goto fail;
1477	} else if (hub->descriptor->bNbrPorts == 0) {
1478		message = "hub doesn't have any ports!";
1479		ret = -ENODEV;
1480		goto fail;
1481	}
1482
1483	/*
1484	 * Accumulate wHubDelay + 40ns for every hub in the tree of devices.
1485	 * The resulting value will be used for SetIsochDelay() request.
1486	 */
1487	if (hub_is_superspeed(hdev) || hub_is_superspeedplus(hdev)) {
1488		u32 delay = __le16_to_cpu(hub->descriptor->u.ss.wHubDelay);
1489
1490		if (hdev->parent)
1491			delay += hdev->parent->hub_delay;
1492
1493		delay += USB_TP_TRANSMISSION_DELAY;
1494		hdev->hub_delay = min_t(u32, delay, USB_TP_TRANSMISSION_DELAY_MAX);
1495	}
1496
1497	maxchild = hub->descriptor->bNbrPorts;
1498	dev_info(hub_dev, "%d port%s detected\n", maxchild,
1499			(maxchild == 1) ? "" : "s");
1500
1501	hub->ports = kcalloc(maxchild, sizeof(struct usb_port *), GFP_KERNEL);
1502	if (!hub->ports) {
1503		ret = -ENOMEM;
1504		goto fail;
1505	}
1506
1507	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
1508	if (hub_is_superspeed(hdev)) {
1509		unit_load = 150;
1510		full_load = 900;
1511	} else {
1512		unit_load = 100;
1513		full_load = 500;
1514	}
1515
1516	/* FIXME for USB 3.0, skip for now */
1517	if ((wHubCharacteristics & HUB_CHAR_COMPOUND) &&
1518			!(hub_is_superspeed(hdev))) {
1519		char	portstr[USB_MAXCHILDREN + 1];
1520
1521		for (i = 0; i < maxchild; i++)
1522			portstr[i] = hub->descriptor->u.hs.DeviceRemovable
1523				    [((i + 1) / 8)] & (1 << ((i + 1) % 8))
1524				? 'F' : 'R';
1525		portstr[maxchild] = 0;
1526		dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
1527	} else
1528		dev_dbg(hub_dev, "standalone hub\n");
1529
1530	switch (wHubCharacteristics & HUB_CHAR_LPSM) {
1531	case HUB_CHAR_COMMON_LPSM:
1532		dev_dbg(hub_dev, "ganged power switching\n");
1533		break;
1534	case HUB_CHAR_INDV_PORT_LPSM:
1535		dev_dbg(hub_dev, "individual port power switching\n");
1536		break;
1537	case HUB_CHAR_NO_LPSM:
1538	case HUB_CHAR_LPSM:
1539		dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
1540		break;
1541	}
1542
1543	switch (wHubCharacteristics & HUB_CHAR_OCPM) {
1544	case HUB_CHAR_COMMON_OCPM:
1545		dev_dbg(hub_dev, "global over-current protection\n");
1546		break;
1547	case HUB_CHAR_INDV_PORT_OCPM:
1548		dev_dbg(hub_dev, "individual port over-current protection\n");
1549		break;
1550	case HUB_CHAR_NO_OCPM:
1551	case HUB_CHAR_OCPM:
1552		dev_dbg(hub_dev, "no over-current protection\n");
1553		break;
1554	}
1555
1556	spin_lock_init(&hub->tt.lock);
1557	INIT_LIST_HEAD(&hub->tt.clear_list);
1558	INIT_WORK(&hub->tt.clear_work, hub_tt_work);
1559	switch (hdev->descriptor.bDeviceProtocol) {
1560	case USB_HUB_PR_FS:
1561		break;
1562	case USB_HUB_PR_HS_SINGLE_TT:
1563		dev_dbg(hub_dev, "Single TT\n");
1564		hub->tt.hub = hdev;
1565		break;
1566	case USB_HUB_PR_HS_MULTI_TT:
1567		ret = usb_set_interface(hdev, 0, 1);
1568		if (ret == 0) {
1569			dev_dbg(hub_dev, "TT per port\n");
1570			hub->tt.multi = 1;
1571		} else
1572			dev_err(hub_dev, "Using single TT (err %d)\n",
1573				ret);
1574		hub->tt.hub = hdev;
1575		break;
1576	case USB_HUB_PR_SS:
1577		/* USB 3.0 hubs don't have a TT */
1578		break;
1579	default:
1580		dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
1581			hdev->descriptor.bDeviceProtocol);
1582		break;
1583	}
1584
1585	/* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
1586	switch (wHubCharacteristics & HUB_CHAR_TTTT) {
1587	case HUB_TTTT_8_BITS:
1588		if (hdev->descriptor.bDeviceProtocol != 0) {
1589			hub->tt.think_time = 666;
1590			dev_dbg(hub_dev, "TT requires at most %d "
1591					"FS bit times (%d ns)\n",
1592				8, hub->tt.think_time);
1593		}
1594		break;
1595	case HUB_TTTT_16_BITS:
1596		hub->tt.think_time = 666 * 2;
1597		dev_dbg(hub_dev, "TT requires at most %d "
1598				"FS bit times (%d ns)\n",
1599			16, hub->tt.think_time);
1600		break;
1601	case HUB_TTTT_24_BITS:
1602		hub->tt.think_time = 666 * 3;
1603		dev_dbg(hub_dev, "TT requires at most %d "
1604				"FS bit times (%d ns)\n",
1605			24, hub->tt.think_time);
1606		break;
1607	case HUB_TTTT_32_BITS:
1608		hub->tt.think_time = 666 * 4;
1609		dev_dbg(hub_dev, "TT requires at most %d "
1610				"FS bit times (%d ns)\n",
1611			32, hub->tt.think_time);
1612		break;
1613	}
1614
1615	/* probe() zeroes hub->indicator[] */
1616	if (wHubCharacteristics & HUB_CHAR_PORTIND) {
1617		hub->has_indicators = 1;
1618		dev_dbg(hub_dev, "Port indicators are supported\n");
1619	}
1620
1621	dev_dbg(hub_dev, "power on to power good time: %dms\n",
1622		hub->descriptor->bPwrOn2PwrGood * 2);
1623
1624	/* power budgeting mostly matters with bus-powered hubs,
1625	 * and battery-powered root hubs (may provide just 8 mA).
1626	 */
1627	ret = usb_get_std_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
1628	if (ret) {
1629		message = "can't get hub status";
1630		goto fail;
1631	}
1632	hcd = bus_to_hcd(hdev->bus);
1633	if (hdev == hdev->bus->root_hub) {
1634		if (hcd->power_budget > 0)
1635			hdev->bus_mA = hcd->power_budget;
1636		else
1637			hdev->bus_mA = full_load * maxchild;
1638		if (hdev->bus_mA >= full_load)
1639			hub->mA_per_port = full_load;
1640		else {
1641			hub->mA_per_port = hdev->bus_mA;
1642			hub->limited_power = 1;
1643		}
1644	} else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1645		int remaining = hdev->bus_mA -
1646			hub->descriptor->bHubContrCurrent;
1647
1648		dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
1649			hub->descriptor->bHubContrCurrent);
1650		hub->limited_power = 1;
1651
1652		if (remaining < maxchild * unit_load)
1653			dev_warn(hub_dev,
1654					"insufficient power available "
1655					"to use all downstream ports\n");
1656		hub->mA_per_port = unit_load;	/* 7.2.1 */
1657
1658	} else {	/* Self-powered external hub */
1659		/* FIXME: What about battery-powered external hubs that
1660		 * provide less current per port? */
1661		hub->mA_per_port = full_load;
1662	}
1663	if (hub->mA_per_port < full_load)
1664		dev_dbg(hub_dev, "%umA bus power budget for each child\n",
1665				hub->mA_per_port);
1666
1667	ret = hub_hub_status(hub, &hubstatus, &hubchange);
1668	if (ret < 0) {
1669		message = "can't get hub status";
1670		goto fail;
1671	}
1672
1673	/* local power status reports aren't always correct */
1674	if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
1675		dev_dbg(hub_dev, "local power source is %s\n",
1676			(hubstatus & HUB_STATUS_LOCAL_POWER)
1677			? "lost (inactive)" : "good");
1678
1679	if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
1680		dev_dbg(hub_dev, "%sover-current condition exists\n",
1681			(hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
1682
1683	/* set up the interrupt endpoint
1684	 * We use the EP's maxpacket size instead of (PORTS+1+7)/8
1685	 * bytes as USB2.0[11.12.3] says because some hubs are known
1686	 * to send more data (and thus cause overflow). For root hubs,
1687	 * maxpktsize is defined in hcd.c's fake endpoint descriptors
1688	 * to be big enough for at least USB_MAXCHILDREN ports. */
1689	pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
1690	maxp = usb_maxpacket(hdev, pipe);
1691
1692	if (maxp > sizeof(*hub->buffer))
1693		maxp = sizeof(*hub->buffer);
1694
1695	hub->urb = usb_alloc_urb(0, GFP_KERNEL);
1696	if (!hub->urb) {
1697		ret = -ENOMEM;
1698		goto fail;
1699	}
1700
1701	usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1702		hub, endpoint->bInterval);
1703
1704	/* maybe cycle the hub leds */
1705	if (hub->has_indicators && blinkenlights)
1706		hub->indicator[0] = INDICATOR_CYCLE;
1707
1708	mutex_lock(&usb_port_peer_mutex);
1709	for (i = 0; i < maxchild; i++) {
1710		ret = usb_hub_create_port_device(hub, i + 1);
1711		if (ret < 0) {
1712			dev_err(hub->intfdev,
1713				"couldn't create port%d device.\n", i + 1);
1714			break;
1715		}
1716	}
1717	hdev->maxchild = i;
1718	for (i = 0; i < hdev->maxchild; i++) {
1719		struct usb_port *port_dev = hub->ports[i];
1720
1721		pm_runtime_put(&port_dev->dev);
1722	}
1723
1724	mutex_unlock(&usb_port_peer_mutex);
1725	if (ret < 0)
1726		goto fail;
1727
1728	/* Update the HCD's internal representation of this hub before hub_wq
1729	 * starts getting port status changes for devices under the hub.
1730	 */
1731	if (hcd->driver->update_hub_device) {
1732		ret = hcd->driver->update_hub_device(hcd, hdev,
1733				&hub->tt, GFP_KERNEL);
1734		if (ret < 0) {
1735			message = "can't update HCD hub info";
1736			goto fail;
1737		}
1738	}
1739
1740	usb_hub_adjust_deviceremovable(hdev, hub->descriptor);
1741
1742	hub_activate(hub, HUB_INIT);
1743	return 0;
1744
1745fail:
1746	dev_err(hub_dev, "config failed, %s (err %d)\n",
1747			message, ret);
1748	/* hub_disconnect() frees urb and descriptor */
1749	return ret;
1750}
1751
1752static void hub_release(struct kref *kref)
1753{
1754	struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1755
1756	usb_put_dev(hub->hdev);
1757	usb_put_intf(to_usb_interface(hub->intfdev));
1758	kfree(hub);
1759}
1760
1761void hub_get(struct usb_hub *hub)
1762{
1763	kref_get(&hub->kref);
1764}
1765
1766void hub_put(struct usb_hub *hub)
1767{
1768	kref_put(&hub->kref, hub_release);
1769}
1770
1771static unsigned highspeed_hubs;
1772
1773static void hub_disconnect(struct usb_interface *intf)
1774{
1775	struct usb_hub *hub = usb_get_intfdata(intf);
1776	struct usb_device *hdev = interface_to_usbdev(intf);
1777	int port1;
1778
1779	/*
1780	 * Stop adding new hub events. We do not want to block here and thus
1781	 * will not try to remove any pending work item.
1782	 */
1783	hub->disconnected = 1;
1784
1785	/* Disconnect all children and quiesce the hub */
1786	hub->error = 0;
1787	hub_quiesce(hub, HUB_DISCONNECT);
1788
1789	mutex_lock(&usb_port_peer_mutex);
1790
1791	/* Avoid races with recursively_mark_NOTATTACHED() */
1792	spin_lock_irq(&device_state_lock);
1793	port1 = hdev->maxchild;
1794	hdev->maxchild = 0;
1795	usb_set_intfdata(intf, NULL);
1796	spin_unlock_irq(&device_state_lock);
1797
1798	for (; port1 > 0; --port1)
1799		usb_hub_remove_port_device(hub, port1);
1800
1801	mutex_unlock(&usb_port_peer_mutex);
1802
1803	if (hub->hdev->speed == USB_SPEED_HIGH)
1804		highspeed_hubs--;
1805
1806	usb_free_urb(hub->urb);
1807	kfree(hub->ports);
1808	kfree(hub->descriptor);
1809	kfree(hub->status);
1810	kfree(hub->buffer);
1811
1812	pm_suspend_ignore_children(&intf->dev, false);
1813
1814	if (hub->quirk_disable_autosuspend)
1815		usb_autopm_put_interface(intf);
1816
1817	onboard_dev_destroy_pdevs(&hub->onboard_devs);
1818
1819	hub_put(hub);
1820}
1821
1822static bool hub_descriptor_is_sane(struct usb_host_interface *desc)
1823{
1824	/* Some hubs have a subclass of 1, which AFAICT according to the */
1825	/*  specs is not defined, but it works */
1826	if (desc->desc.bInterfaceSubClass != 0 &&
1827	    desc->desc.bInterfaceSubClass != 1)
1828		return false;
1829
1830	/* Multiple endpoints? What kind of mutant ninja-hub is this? */
1831	if (desc->desc.bNumEndpoints != 1)
1832		return false;
1833
1834	/* If the first endpoint is not interrupt IN, we'd better punt! */
1835	if (!usb_endpoint_is_int_in(&desc->endpoint[0].desc))
1836		return false;
1837
1838        return true;
1839}
1840
1841static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1842{
1843	struct usb_host_interface *desc;
1844	struct usb_device *hdev;
1845	struct usb_hub *hub;
1846
1847	desc = intf->cur_altsetting;
1848	hdev = interface_to_usbdev(intf);
1849
1850	/*
1851	 * The USB 2.0 spec prohibits hubs from having more than one
1852	 * configuration or interface, and we rely on this prohibition.
1853	 * Refuse to accept a device that violates it.
1854	 */
1855	if (hdev->descriptor.bNumConfigurations > 1 ||
1856			hdev->actconfig->desc.bNumInterfaces > 1) {
1857		dev_err(&intf->dev, "Invalid hub with more than one config or interface\n");
1858		return -EINVAL;
1859	}
1860
1861	/*
1862	 * Set default autosuspend delay as 0 to speedup bus suspend,
1863	 * based on the below considerations:
1864	 *
1865	 * - Unlike other drivers, the hub driver does not rely on the
1866	 *   autosuspend delay to provide enough time to handle a wakeup
1867	 *   event, and the submitted status URB is just to check future
1868	 *   change on hub downstream ports, so it is safe to do it.
1869	 *
1870	 * - The patch might cause one or more auto supend/resume for
1871	 *   below very rare devices when they are plugged into hub
1872	 *   first time:
1873	 *
1874	 *   	devices having trouble initializing, and disconnect
1875	 *   	themselves from the bus and then reconnect a second
1876	 *   	or so later
1877	 *
1878	 *   	devices just for downloading firmware, and disconnects
1879	 *   	themselves after completing it
1880	 *
1881	 *   For these quite rare devices, their drivers may change the
1882	 *   autosuspend delay of their parent hub in the probe() to one
1883	 *   appropriate value to avoid the subtle problem if someone
1884	 *   does care it.
1885	 *
1886	 * - The patch may cause one or more auto suspend/resume on
1887	 *   hub during running 'lsusb', but it is probably too
1888	 *   infrequent to worry about.
1889	 *
1890	 * - Change autosuspend delay of hub can avoid unnecessary auto
1891	 *   suspend timer for hub, also may decrease power consumption
1892	 *   of USB bus.
1893	 *
1894	 * - If user has indicated to prevent autosuspend by passing
1895	 *   usbcore.autosuspend = -1 then keep autosuspend disabled.
1896	 */
1897#ifdef CONFIG_PM
1898	if (hdev->dev.power.autosuspend_delay >= 0)
1899		pm_runtime_set_autosuspend_delay(&hdev->dev, 0);
1900#endif
1901
1902	/*
1903	 * Hubs have proper suspend/resume support, except for root hubs
1904	 * where the controller driver doesn't have bus_suspend and
1905	 * bus_resume methods.
1906	 */
1907	if (hdev->parent) {		/* normal device */
1908		usb_enable_autosuspend(hdev);
1909	} else {			/* root hub */
1910		const struct hc_driver *drv = bus_to_hcd(hdev->bus)->driver;
1911
1912		if (drv->bus_suspend && drv->bus_resume)
1913			usb_enable_autosuspend(hdev);
1914	}
1915
1916	if (hdev->level == MAX_TOPO_LEVEL) {
1917		dev_err(&intf->dev,
1918			"Unsupported bus topology: hub nested too deep\n");
1919		return -E2BIG;
1920	}
1921
1922#ifdef	CONFIG_USB_OTG_DISABLE_EXTERNAL_HUB
1923	if (hdev->parent) {
1924		dev_warn(&intf->dev, "ignoring external hub\n");
1925		return -ENODEV;
1926	}
1927#endif
1928
1929	if (!hub_descriptor_is_sane(desc)) {
1930		dev_err(&intf->dev, "bad descriptor, ignoring hub\n");
1931		return -EIO;
1932	}
1933
1934	/* We found a hub */
1935	dev_info(&intf->dev, "USB hub found\n");
1936
1937	hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1938	if (!hub)
1939		return -ENOMEM;
1940
1941	kref_init(&hub->kref);
1942	hub->intfdev = &intf->dev;
1943	hub->hdev = hdev;
1944	INIT_DELAYED_WORK(&hub->leds, led_work);
1945	INIT_DELAYED_WORK(&hub->init_work, NULL);
1946	INIT_WORK(&hub->events, hub_event);
1947	INIT_LIST_HEAD(&hub->onboard_devs);
1948	spin_lock_init(&hub->irq_urb_lock);
1949	timer_setup(&hub->irq_urb_retry, hub_retry_irq_urb, 0);
1950	usb_get_intf(intf);
1951	usb_get_dev(hdev);
1952
1953	usb_set_intfdata(intf, hub);
1954	intf->needs_remote_wakeup = 1;
1955	pm_suspend_ignore_children(&intf->dev, true);
1956
1957	if (hdev->speed == USB_SPEED_HIGH)
1958		highspeed_hubs++;
1959
1960	if (id->driver_info & HUB_QUIRK_CHECK_PORT_AUTOSUSPEND)
1961		hub->quirk_check_port_auto_suspend = 1;
1962
1963	if (id->driver_info & HUB_QUIRK_DISABLE_AUTOSUSPEND) {
1964		hub->quirk_disable_autosuspend = 1;
1965		usb_autopm_get_interface_no_resume(intf);
1966	}
1967
1968	if ((id->driver_info & HUB_QUIRK_REDUCE_FRAME_INTR_BINTERVAL) &&
1969	    desc->endpoint[0].desc.bInterval > USB_REDUCE_FRAME_INTR_BINTERVAL) {
1970		desc->endpoint[0].desc.bInterval =
1971			USB_REDUCE_FRAME_INTR_BINTERVAL;
1972		/* Tell the HCD about the interrupt ep's new bInterval */
1973		usb_set_interface(hdev, 0, 0);
1974	}
1975
1976	if (hub_configure(hub, &desc->endpoint[0].desc) >= 0) {
1977		onboard_dev_create_pdevs(hdev, &hub->onboard_devs);
1978
1979		return 0;
1980	}
1981
1982	hub_disconnect(intf);
1983	return -ENODEV;
1984}
1985
1986static int
1987hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1988{
1989	struct usb_device *hdev = interface_to_usbdev(intf);
1990	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
1991
1992	/* assert ifno == 0 (part of hub spec) */
1993	switch (code) {
1994	case USBDEVFS_HUB_PORTINFO: {
1995		struct usbdevfs_hub_portinfo *info = user_data;
1996		int i;
1997
1998		spin_lock_irq(&device_state_lock);
1999		if (hdev->devnum <= 0)
2000			info->nports = 0;
2001		else {
2002			info->nports = hdev->maxchild;
2003			for (i = 0; i < info->nports; i++) {
2004				if (hub->ports[i]->child == NULL)
2005					info->port[i] = 0;
2006				else
2007					info->port[i] =
2008						hub->ports[i]->child->devnum;
2009			}
2010		}
2011		spin_unlock_irq(&device_state_lock);
2012
2013		return info->nports + 1;
2014		}
2015
2016	default:
2017		return -ENOSYS;
2018	}
2019}
2020
2021/*
2022 * Allow user programs to claim ports on a hub.  When a device is attached
2023 * to one of these "claimed" ports, the program will "own" the device.
2024 */
2025static int find_port_owner(struct usb_device *hdev, unsigned port1,
2026		struct usb_dev_state ***ppowner)
2027{
2028	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
2029
2030	if (hdev->state == USB_STATE_NOTATTACHED)
2031		return -ENODEV;
2032	if (port1 == 0 || port1 > hdev->maxchild)
2033		return -EINVAL;
2034
2035	/* Devices not managed by the hub driver
2036	 * will always have maxchild equal to 0.
2037	 */
2038	*ppowner = &(hub->ports[port1 - 1]->port_owner);
2039	return 0;
2040}
2041
2042/* In the following three functions, the caller must hold hdev's lock */
2043int usb_hub_claim_port(struct usb_device *hdev, unsigned port1,
2044		       struct usb_dev_state *owner)
2045{
2046	int rc;
2047	struct usb_dev_state **powner;
2048
2049	rc = find_port_owner(hdev, port1, &powner);
2050	if (rc)
2051		return rc;
2052	if (*powner)
2053		return -EBUSY;
2054	*powner = owner;
2055	return rc;
2056}
2057EXPORT_SYMBOL_GPL(usb_hub_claim_port);
2058
2059int usb_hub_release_port(struct usb_device *hdev, unsigned port1,
2060			 struct usb_dev_state *owner)
2061{
2062	int rc;
2063	struct usb_dev_state **powner;
2064
2065	rc = find_port_owner(hdev, port1, &powner);
2066	if (rc)
2067		return rc;
2068	if (*powner != owner)
2069		return -ENOENT;
2070	*powner = NULL;
2071	return rc;
2072}
2073EXPORT_SYMBOL_GPL(usb_hub_release_port);
2074
2075void usb_hub_release_all_ports(struct usb_device *hdev, struct usb_dev_state *owner)
2076{
2077	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
2078	int n;
2079
2080	for (n = 0; n < hdev->maxchild; n++) {
2081		if (hub->ports[n]->port_owner == owner)
2082			hub->ports[n]->port_owner = NULL;
2083	}
2084
2085}
2086
2087/* The caller must hold udev's lock */
2088bool usb_device_is_owned(struct usb_device *udev)
2089{
2090	struct usb_hub *hub;
2091
2092	if (udev->state == USB_STATE_NOTATTACHED || !udev->parent)
2093		return false;
2094	hub = usb_hub_to_struct_hub(udev->parent);
2095	return !!hub->ports[udev->portnum - 1]->port_owner;
2096}
2097
2098static void update_port_device_state(struct usb_device *udev)
2099{
2100	struct usb_hub *hub;
2101	struct usb_port *port_dev;
2102
2103	if (udev->parent) {
2104		hub = usb_hub_to_struct_hub(udev->parent);
2105
2106		/*
2107		 * The Link Layer Validation System Driver (lvstest)
2108		 * has a test step to unbind the hub before running the
2109		 * rest of the procedure. This triggers hub_disconnect
2110		 * which will set the hub's maxchild to 0, further
2111		 * resulting in usb_hub_to_struct_hub returning NULL.
2112		 */
2113		if (hub) {
2114			port_dev = hub->ports[udev->portnum - 1];
2115			WRITE_ONCE(port_dev->state, udev->state);
2116			sysfs_notify_dirent(port_dev->state_kn);
2117		}
2118	}
2119}
2120
2121static void recursively_mark_NOTATTACHED(struct usb_device *udev)
2122{
2123	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
2124	int i;
2125
2126	for (i = 0; i < udev->maxchild; ++i) {
2127		if (hub->ports[i]->child)
2128			recursively_mark_NOTATTACHED(hub->ports[i]->child);
2129	}
2130	if (udev->state == USB_STATE_SUSPENDED)
2131		udev->active_duration -= jiffies;
2132	udev->state = USB_STATE_NOTATTACHED;
2133	update_port_device_state(udev);
2134}
2135
2136/**
2137 * usb_set_device_state - change a device's current state (usbcore, hcds)
2138 * @udev: pointer to device whose state should be changed
2139 * @new_state: new state value to be stored
2140 *
2141 * udev->state is _not_ fully protected by the device lock.  Although
2142 * most transitions are made only while holding the lock, the state can
2143 * can change to USB_STATE_NOTATTACHED at almost any time.  This
2144 * is so that devices can be marked as disconnected as soon as possible,
2145 * without having to wait for any semaphores to be released.  As a result,
2146 * all changes to any device's state must be protected by the
2147 * device_state_lock spinlock.
2148 *
2149 * Once a device has been added to the device tree, all changes to its state
2150 * should be made using this routine.  The state should _not_ be set directly.
2151 *
2152 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
2153 * Otherwise udev->state is set to new_state, and if new_state is
2154 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
2155 * to USB_STATE_NOTATTACHED.
2156 */
2157void usb_set_device_state(struct usb_device *udev,
2158		enum usb_device_state new_state)
2159{
2160	unsigned long flags;
2161	int wakeup = -1;
2162
2163	spin_lock_irqsave(&device_state_lock, flags);
2164	if (udev->state == USB_STATE_NOTATTACHED)
2165		;	/* do nothing */
2166	else if (new_state != USB_STATE_NOTATTACHED) {
2167
2168		/* root hub wakeup capabilities are managed out-of-band
2169		 * and may involve silicon errata ... ignore them here.
2170		 */
2171		if (udev->parent) {
2172			if (udev->state == USB_STATE_SUSPENDED
2173					|| new_state == USB_STATE_SUSPENDED)
2174				;	/* No change to wakeup settings */
2175			else if (new_state == USB_STATE_CONFIGURED)
2176				wakeup = (udev->quirks &
2177					USB_QUIRK_IGNORE_REMOTE_WAKEUP) ? 0 :
2178					udev->actconfig->desc.bmAttributes &
2179					USB_CONFIG_ATT_WAKEUP;
2180			else
2181				wakeup = 0;
2182		}
2183		if (udev->state == USB_STATE_SUSPENDED &&
2184			new_state != USB_STATE_SUSPENDED)
2185			udev->active_duration -= jiffies;
2186		else if (new_state == USB_STATE_SUSPENDED &&
2187				udev->state != USB_STATE_SUSPENDED)
2188			udev->active_duration += jiffies;
2189		udev->state = new_state;
2190		update_port_device_state(udev);
2191	} else
2192		recursively_mark_NOTATTACHED(udev);
2193	spin_unlock_irqrestore(&device_state_lock, flags);
2194	if (wakeup >= 0)
2195		device_set_wakeup_capable(&udev->dev, wakeup);
2196}
2197EXPORT_SYMBOL_GPL(usb_set_device_state);
2198
2199/*
2200 * Choose a device number.
2201 *
2202 * Device numbers are used as filenames in usbfs.  On USB-1.1 and
2203 * USB-2.0 buses they are also used as device addresses, however on
2204 * USB-3.0 buses the address is assigned by the controller hardware
2205 * and it usually is not the same as the device number.
2206 *
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2207 * Devices connected under xHCI are not as simple.  The host controller
2208 * supports virtualization, so the hardware assigns device addresses and
2209 * the HCD must setup data structures before issuing a set address
2210 * command to the hardware.
2211 */
2212static void choose_devnum(struct usb_device *udev)
2213{
2214	int		devnum;
2215	struct usb_bus	*bus = udev->bus;
2216
2217	/* be safe when more hub events are proceed in parallel */
2218	mutex_lock(&bus->devnum_next_mutex);
2219
2220	/* Try to allocate the next devnum beginning at bus->devnum_next. */
2221	devnum = find_next_zero_bit(bus->devmap, 128, bus->devnum_next);
2222	if (devnum >= 128)
2223		devnum = find_next_zero_bit(bus->devmap, 128, 1);
2224	bus->devnum_next = (devnum >= 127 ? 1 : devnum + 1);
 
 
 
 
 
 
 
2225	if (devnum < 128) {
2226		set_bit(devnum, bus->devmap);
2227		udev->devnum = devnum;
2228	}
2229	mutex_unlock(&bus->devnum_next_mutex);
2230}
2231
2232static void release_devnum(struct usb_device *udev)
2233{
2234	if (udev->devnum > 0) {
2235		clear_bit(udev->devnum, udev->bus->devmap);
2236		udev->devnum = -1;
2237	}
2238}
2239
2240static void update_devnum(struct usb_device *udev, int devnum)
2241{
2242	udev->devnum = devnum;
 
 
2243	if (!udev->devaddr)
2244		udev->devaddr = (u8)devnum;
2245}
2246
2247static void hub_free_dev(struct usb_device *udev)
2248{
2249	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2250
2251	/* Root hubs aren't real devices, so don't free HCD resources */
2252	if (hcd->driver->free_dev && udev->parent)
2253		hcd->driver->free_dev(hcd, udev);
2254}
2255
2256static void hub_disconnect_children(struct usb_device *udev)
2257{
2258	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
2259	int i;
2260
2261	/* Free up all the children before we remove this device */
2262	for (i = 0; i < udev->maxchild; i++) {
2263		if (hub->ports[i]->child)
2264			usb_disconnect(&hub->ports[i]->child);
2265	}
2266}
2267
2268/**
2269 * usb_disconnect - disconnect a device (usbcore-internal)
2270 * @pdev: pointer to device being disconnected
2271 *
2272 * Context: task context, might sleep
2273 *
2274 * Something got disconnected. Get rid of it and all of its children.
2275 *
2276 * If *pdev is a normal device then the parent hub must already be locked.
2277 * If *pdev is a root hub then the caller must hold the usb_bus_idr_lock,
2278 * which protects the set of root hubs as well as the list of buses.
2279 *
2280 * Only hub drivers (including virtual root hub drivers for host
2281 * controllers) should ever call this.
2282 *
2283 * This call is synchronous, and may not be used in an interrupt context.
2284 */
2285void usb_disconnect(struct usb_device **pdev)
2286{
2287	struct usb_port *port_dev = NULL;
2288	struct usb_device *udev = *pdev;
2289	struct usb_hub *hub = NULL;
2290	int port1 = 1;
2291
2292	/* mark the device as inactive, so any further urb submissions for
2293	 * this device (and any of its children) will fail immediately.
2294	 * this quiesces everything except pending urbs.
2295	 */
2296	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2297	dev_info(&udev->dev, "USB disconnect, device number %d\n",
2298			udev->devnum);
2299
2300	/*
2301	 * Ensure that the pm runtime code knows that the USB device
2302	 * is in the process of being disconnected.
2303	 */
2304	pm_runtime_barrier(&udev->dev);
2305
2306	usb_lock_device(udev);
2307
2308	hub_disconnect_children(udev);
2309
2310	/* deallocate hcd/hardware state ... nuking all pending urbs and
2311	 * cleaning up all state associated with the current configuration
2312	 * so that the hardware is now fully quiesced.
2313	 */
2314	dev_dbg(&udev->dev, "unregistering device\n");
2315	usb_disable_device(udev, 0);
2316	usb_hcd_synchronize_unlinks(udev);
2317
2318	if (udev->parent) {
2319		port1 = udev->portnum;
2320		hub = usb_hub_to_struct_hub(udev->parent);
2321		port_dev = hub->ports[port1 - 1];
2322
2323		sysfs_remove_link(&udev->dev.kobj, "port");
2324		sysfs_remove_link(&port_dev->dev.kobj, "device");
2325
2326		/*
2327		 * As usb_port_runtime_resume() de-references udev, make
2328		 * sure no resumes occur during removal
2329		 */
2330		if (!test_and_set_bit(port1, hub->child_usage_bits))
2331			pm_runtime_get_sync(&port_dev->dev);
2332
2333		typec_deattach(port_dev->connector, &udev->dev);
2334	}
2335
2336	usb_remove_ep_devs(&udev->ep0);
2337	usb_unlock_device(udev);
2338
2339	/* Unregister the device.  The device driver is responsible
2340	 * for de-configuring the device and invoking the remove-device
2341	 * notifier chain (used by usbfs and possibly others).
2342	 */
2343	device_del(&udev->dev);
2344
2345	/* Free the device number and delete the parent's children[]
2346	 * (or root_hub) pointer.
2347	 */
2348	release_devnum(udev);
2349
2350	/* Avoid races with recursively_mark_NOTATTACHED() */
2351	spin_lock_irq(&device_state_lock);
2352	*pdev = NULL;
2353	spin_unlock_irq(&device_state_lock);
2354
2355	if (port_dev && test_and_clear_bit(port1, hub->child_usage_bits))
2356		pm_runtime_put(&port_dev->dev);
2357
2358	hub_free_dev(udev);
2359
2360	put_device(&udev->dev);
2361}
2362
2363#ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
2364static void show_string(struct usb_device *udev, char *id, char *string)
2365{
2366	if (!string)
2367		return;
2368	dev_info(&udev->dev, "%s: %s\n", id, string);
2369}
2370
2371static void announce_device(struct usb_device *udev)
2372{
2373	u16 bcdDevice = le16_to_cpu(udev->descriptor.bcdDevice);
2374
2375	dev_info(&udev->dev,
2376		"New USB device found, idVendor=%04x, idProduct=%04x, bcdDevice=%2x.%02x\n",
2377		le16_to_cpu(udev->descriptor.idVendor),
2378		le16_to_cpu(udev->descriptor.idProduct),
2379		bcdDevice >> 8, bcdDevice & 0xff);
2380	dev_info(&udev->dev,
2381		"New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
2382		udev->descriptor.iManufacturer,
2383		udev->descriptor.iProduct,
2384		udev->descriptor.iSerialNumber);
2385	show_string(udev, "Product", udev->product);
2386	show_string(udev, "Manufacturer", udev->manufacturer);
2387	show_string(udev, "SerialNumber", udev->serial);
2388}
2389#else
2390static inline void announce_device(struct usb_device *udev) { }
2391#endif
2392
2393
2394/**
2395 * usb_enumerate_device_otg - FIXME (usbcore-internal)
2396 * @udev: newly addressed device (in ADDRESS state)
2397 *
2398 * Finish enumeration for On-The-Go devices
2399 *
2400 * Return: 0 if successful. A negative error code otherwise.
2401 */
2402static int usb_enumerate_device_otg(struct usb_device *udev)
2403{
2404	int err = 0;
2405
2406#ifdef	CONFIG_USB_OTG
2407	/*
2408	 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
2409	 * to wake us after we've powered off VBUS; and HNP, switching roles
2410	 * "host" to "peripheral".  The OTG descriptor helps figure this out.
2411	 */
2412	if (!udev->bus->is_b_host
2413			&& udev->config
2414			&& udev->parent == udev->bus->root_hub) {
2415		struct usb_otg_descriptor	*desc = NULL;
2416		struct usb_bus			*bus = udev->bus;
2417		unsigned			port1 = udev->portnum;
2418
2419		/* descriptor may appear anywhere in config */
2420		err = __usb_get_extra_descriptor(udev->rawdescriptors[0],
2421				le16_to_cpu(udev->config[0].desc.wTotalLength),
2422				USB_DT_OTG, (void **) &desc, sizeof(*desc));
2423		if (err || !(desc->bmAttributes & USB_OTG_HNP))
2424			return 0;
2425
2426		dev_info(&udev->dev, "Dual-Role OTG device on %sHNP port\n",
2427					(port1 == bus->otg_port) ? "" : "non-");
2428
2429		/* enable HNP before suspend, it's simpler */
2430		if (port1 == bus->otg_port) {
2431			bus->b_hnp_enable = 1;
2432			err = usb_control_msg(udev,
2433				usb_sndctrlpipe(udev, 0),
2434				USB_REQ_SET_FEATURE, 0,
2435				USB_DEVICE_B_HNP_ENABLE,
2436				0, NULL, 0,
2437				USB_CTRL_SET_TIMEOUT);
2438			if (err < 0) {
2439				/*
2440				 * OTG MESSAGE: report errors here,
2441				 * customize to match your product.
2442				 */
2443				dev_err(&udev->dev, "can't set HNP mode: %d\n",
2444									err);
2445				bus->b_hnp_enable = 0;
2446			}
2447		} else if (desc->bLength == sizeof
2448				(struct usb_otg_descriptor)) {
2449			/*
2450			 * We are operating on a legacy OTP device
2451			 * These should be told that they are operating
2452			 * on the wrong port if we have another port that does
2453			 * support HNP
2454			 */
2455			if (bus->otg_port != 0) {
2456				/* Set a_alt_hnp_support for legacy otg device */
2457				err = usb_control_msg(udev,
2458					usb_sndctrlpipe(udev, 0),
2459					USB_REQ_SET_FEATURE, 0,
2460					USB_DEVICE_A_ALT_HNP_SUPPORT,
2461					0, NULL, 0,
2462					USB_CTRL_SET_TIMEOUT);
2463				if (err < 0)
2464					dev_err(&udev->dev,
2465						"set a_alt_hnp_support failed: %d\n",
2466						err);
2467			}
2468		}
2469	}
2470#endif
2471	return err;
2472}
2473
2474
2475/**
2476 * usb_enumerate_device - Read device configs/intfs/otg (usbcore-internal)
2477 * @udev: newly addressed device (in ADDRESS state)
2478 *
2479 * This is only called by usb_new_device() -- all comments that apply there
2480 * apply here wrt to environment.
 
2481 *
2482 * If the device is WUSB and not authorized, we don't attempt to read
2483 * the string descriptors, as they will be errored out by the device
2484 * until it has been authorized.
2485 *
2486 * Return: 0 if successful. A negative error code otherwise.
2487 */
2488static int usb_enumerate_device(struct usb_device *udev)
2489{
2490	int err;
2491	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2492
2493	if (udev->config == NULL) {
2494		err = usb_get_configuration(udev);
2495		if (err < 0) {
2496			if (err != -ENODEV)
2497				dev_err(&udev->dev, "can't read configurations, error %d\n",
2498						err);
2499			return err;
2500		}
2501	}
2502
2503	/* read the standard strings and cache them if present */
2504	udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
2505	udev->manufacturer = usb_cache_string(udev,
2506					      udev->descriptor.iManufacturer);
2507	udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
2508
2509	err = usb_enumerate_device_otg(udev);
2510	if (err < 0)
2511		return err;
2512
2513	if (IS_ENABLED(CONFIG_USB_OTG_PRODUCTLIST) && hcd->tpl_support &&
2514		!is_targeted(udev)) {
2515		/* Maybe it can talk to us, though we can't talk to it.
2516		 * (Includes HNP test device.)
2517		 */
2518		if (IS_ENABLED(CONFIG_USB_OTG) && (udev->bus->b_hnp_enable
2519			|| udev->bus->is_b_host)) {
2520			err = usb_port_suspend(udev, PMSG_AUTO_SUSPEND);
2521			if (err < 0)
2522				dev_dbg(&udev->dev, "HNP fail, %d\n", err);
2523		}
2524		return -ENOTSUPP;
2525	}
2526
2527	usb_detect_interface_quirks(udev);
2528
2529	return 0;
2530}
2531
2532static void set_usb_port_removable(struct usb_device *udev)
2533{
2534	struct usb_device *hdev = udev->parent;
2535	struct usb_hub *hub;
2536	u8 port = udev->portnum;
2537	u16 wHubCharacteristics;
2538	bool removable = true;
2539
2540	dev_set_removable(&udev->dev, DEVICE_REMOVABLE_UNKNOWN);
2541
2542	if (!hdev)
2543		return;
2544
2545	hub = usb_hub_to_struct_hub(udev->parent);
2546
2547	/*
2548	 * If the platform firmware has provided information about a port,
2549	 * use that to determine whether it's removable.
2550	 */
2551	switch (hub->ports[udev->portnum - 1]->connect_type) {
2552	case USB_PORT_CONNECT_TYPE_HOT_PLUG:
2553		dev_set_removable(&udev->dev, DEVICE_REMOVABLE);
2554		return;
2555	case USB_PORT_CONNECT_TYPE_HARD_WIRED:
2556	case USB_PORT_NOT_USED:
2557		dev_set_removable(&udev->dev, DEVICE_FIXED);
2558		return;
2559	default:
2560		break;
2561	}
2562
2563	/*
2564	 * Otherwise, check whether the hub knows whether a port is removable
2565	 * or not
2566	 */
2567	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2568
2569	if (!(wHubCharacteristics & HUB_CHAR_COMPOUND))
2570		return;
2571
2572	if (hub_is_superspeed(hdev)) {
2573		if (le16_to_cpu(hub->descriptor->u.ss.DeviceRemovable)
2574				& (1 << port))
2575			removable = false;
2576	} else {
2577		if (hub->descriptor->u.hs.DeviceRemovable[port / 8] & (1 << (port % 8)))
2578			removable = false;
2579	}
2580
2581	if (removable)
2582		dev_set_removable(&udev->dev, DEVICE_REMOVABLE);
2583	else
2584		dev_set_removable(&udev->dev, DEVICE_FIXED);
2585
2586}
2587
2588/**
2589 * usb_new_device - perform initial device setup (usbcore-internal)
2590 * @udev: newly addressed device (in ADDRESS state)
2591 *
2592 * This is called with devices which have been detected but not fully
2593 * enumerated.  The device descriptor is available, but not descriptors
2594 * for any device configuration.  The caller must have locked either
2595 * the parent hub (if udev is a normal device) or else the
2596 * usb_bus_idr_lock (if udev is a root hub).  The parent's pointer to
2597 * udev has already been installed, but udev is not yet visible through
2598 * sysfs or other filesystem code.
2599 *
2600 * This call is synchronous, and may not be used in an interrupt context.
2601 *
2602 * Only the hub driver or root-hub registrar should ever call this.
2603 *
2604 * Return: Whether the device is configured properly or not. Zero if the
2605 * interface was registered with the driver core; else a negative errno
2606 * value.
2607 *
2608 */
2609int usb_new_device(struct usb_device *udev)
2610{
2611	int err;
2612
2613	if (udev->parent) {
2614		/* Initialize non-root-hub device wakeup to disabled;
2615		 * device (un)configuration controls wakeup capable
2616		 * sysfs power/wakeup controls wakeup enabled/disabled
2617		 */
2618		device_init_wakeup(&udev->dev, 0);
2619	}
2620
2621	/* Tell the runtime-PM framework the device is active */
2622	pm_runtime_set_active(&udev->dev);
2623	pm_runtime_get_noresume(&udev->dev);
2624	pm_runtime_use_autosuspend(&udev->dev);
2625	pm_runtime_enable(&udev->dev);
2626
2627	/* By default, forbid autosuspend for all devices.  It will be
2628	 * allowed for hubs during binding.
2629	 */
2630	usb_disable_autosuspend(udev);
2631
2632	err = usb_enumerate_device(udev);	/* Read descriptors */
2633	if (err < 0)
2634		goto fail;
2635	dev_dbg(&udev->dev, "udev %d, busnum %d, minor = %d\n",
2636			udev->devnum, udev->bus->busnum,
2637			(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2638	/* export the usbdev device-node for libusb */
2639	udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
2640			(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2641
2642	/* Tell the world! */
2643	announce_device(udev);
2644
2645	if (udev->serial)
2646		add_device_randomness(udev->serial, strlen(udev->serial));
2647	if (udev->product)
2648		add_device_randomness(udev->product, strlen(udev->product));
2649	if (udev->manufacturer)
2650		add_device_randomness(udev->manufacturer,
2651				      strlen(udev->manufacturer));
2652
2653	device_enable_async_suspend(&udev->dev);
2654
2655	/* check whether the hub or firmware marks this port as non-removable */
2656	set_usb_port_removable(udev);
2657
2658	/* Register the device.  The device driver is responsible
2659	 * for configuring the device and invoking the add-device
2660	 * notifier chain (used by usbfs and possibly others).
2661	 */
2662	err = device_add(&udev->dev);
2663	if (err) {
2664		dev_err(&udev->dev, "can't device_add, error %d\n", err);
2665		goto fail;
2666	}
2667
2668	/* Create link files between child device and usb port device. */
2669	if (udev->parent) {
2670		struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
2671		int port1 = udev->portnum;
2672		struct usb_port	*port_dev = hub->ports[port1 - 1];
2673
2674		err = sysfs_create_link(&udev->dev.kobj,
2675				&port_dev->dev.kobj, "port");
2676		if (err)
2677			goto out_del_dev;
2678
2679		err = sysfs_create_link(&port_dev->dev.kobj,
2680				&udev->dev.kobj, "device");
2681		if (err) {
2682			sysfs_remove_link(&udev->dev.kobj, "port");
2683			goto out_del_dev;
2684		}
2685
2686		if (!test_and_set_bit(port1, hub->child_usage_bits))
2687			pm_runtime_get_sync(&port_dev->dev);
2688
2689		typec_attach(port_dev->connector, &udev->dev);
2690	}
2691
2692	(void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev);
2693	usb_mark_last_busy(udev);
2694	pm_runtime_put_sync_autosuspend(&udev->dev);
2695	return err;
2696
2697out_del_dev:
2698	device_del(&udev->dev);
2699fail:
2700	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2701	pm_runtime_disable(&udev->dev);
2702	pm_runtime_set_suspended(&udev->dev);
2703	return err;
2704}
2705
2706
2707/**
2708 * usb_deauthorize_device - deauthorize a device (usbcore-internal)
2709 * @usb_dev: USB device
2710 *
2711 * Move the USB device to a very basic state where interfaces are disabled
2712 * and the device is in fact unconfigured and unusable.
2713 *
2714 * We share a lock (that we have) with device_del(), so we need to
2715 * defer its call.
2716 *
2717 * Return: 0.
2718 */
2719int usb_deauthorize_device(struct usb_device *usb_dev)
2720{
2721	usb_lock_device(usb_dev);
2722	if (usb_dev->authorized == 0)
2723		goto out_unauthorized;
2724
2725	usb_dev->authorized = 0;
2726	usb_set_configuration(usb_dev, -1);
2727
2728out_unauthorized:
2729	usb_unlock_device(usb_dev);
2730	return 0;
2731}
2732
2733
2734int usb_authorize_device(struct usb_device *usb_dev)
2735{
2736	int result = 0, c;
2737
2738	usb_lock_device(usb_dev);
2739	if (usb_dev->authorized == 1)
2740		goto out_authorized;
2741
2742	result = usb_autoresume_device(usb_dev);
2743	if (result < 0) {
2744		dev_err(&usb_dev->dev,
2745			"can't autoresume for authorization: %d\n", result);
2746		goto error_autoresume;
2747	}
2748
 
 
 
 
 
 
 
 
 
2749	usb_dev->authorized = 1;
2750	/* Choose and set the configuration.  This registers the interfaces
2751	 * with the driver core and lets interface drivers bind to them.
2752	 */
2753	c = usb_choose_configuration(usb_dev);
2754	if (c >= 0) {
2755		result = usb_set_configuration(usb_dev, c);
2756		if (result) {
2757			dev_err(&usb_dev->dev,
2758				"can't set config #%d, error %d\n", c, result);
2759			/* This need not be fatal.  The user can try to
2760			 * set other configurations. */
2761		}
2762	}
2763	dev_info(&usb_dev->dev, "authorized to connect\n");
2764
 
2765	usb_autosuspend_device(usb_dev);
2766error_autoresume:
2767out_authorized:
2768	usb_unlock_device(usb_dev);	/* complements locktree */
2769	return result;
2770}
2771
2772/**
2773 * get_port_ssp_rate - Match the extended port status to SSP rate
2774 * @hdev: The hub device
2775 * @ext_portstatus: extended port status
2776 *
2777 * Match the extended port status speed id to the SuperSpeed Plus sublink speed
2778 * capability attributes. Base on the number of connected lanes and speed,
2779 * return the corresponding enum usb_ssp_rate.
2780 */
2781static enum usb_ssp_rate get_port_ssp_rate(struct usb_device *hdev,
2782					   u32 ext_portstatus)
2783{
2784	struct usb_ssp_cap_descriptor *ssp_cap;
2785	u32 attr;
2786	u8 speed_id;
2787	u8 ssac;
2788	u8 lanes;
2789	int i;
2790
2791	if (!hdev->bos)
2792		goto out;
2793
2794	ssp_cap = hdev->bos->ssp_cap;
2795	if (!ssp_cap)
2796		goto out;
2797
2798	speed_id = ext_portstatus & USB_EXT_PORT_STAT_RX_SPEED_ID;
2799	lanes = USB_EXT_PORT_RX_LANES(ext_portstatus) + 1;
2800
2801	ssac = le32_to_cpu(ssp_cap->bmAttributes) &
2802		USB_SSP_SUBLINK_SPEED_ATTRIBS;
2803
2804	for (i = 0; i <= ssac; i++) {
2805		u8 ssid;
2806
2807		attr = le32_to_cpu(ssp_cap->bmSublinkSpeedAttr[i]);
2808		ssid = FIELD_GET(USB_SSP_SUBLINK_SPEED_SSID, attr);
2809		if (speed_id == ssid) {
2810			u16 mantissa;
2811			u8 lse;
2812			u8 type;
2813
2814			/*
2815			 * Note: currently asymmetric lane types are only
2816			 * applicable for SSIC operate in SuperSpeed protocol
2817			 */
2818			type = FIELD_GET(USB_SSP_SUBLINK_SPEED_ST, attr);
2819			if (type == USB_SSP_SUBLINK_SPEED_ST_ASYM_RX ||
2820			    type == USB_SSP_SUBLINK_SPEED_ST_ASYM_TX)
2821				goto out;
2822
2823			if (FIELD_GET(USB_SSP_SUBLINK_SPEED_LP, attr) !=
2824			    USB_SSP_SUBLINK_SPEED_LP_SSP)
2825				goto out;
2826
2827			lse = FIELD_GET(USB_SSP_SUBLINK_SPEED_LSE, attr);
2828			mantissa = FIELD_GET(USB_SSP_SUBLINK_SPEED_LSM, attr);
2829
2830			/* Convert to Gbps */
2831			for (; lse < USB_SSP_SUBLINK_SPEED_LSE_GBPS; lse++)
2832				mantissa /= 1000;
2833
2834			if (mantissa >= 10 && lanes == 1)
2835				return USB_SSP_GEN_2x1;
2836
2837			if (mantissa >= 10 && lanes == 2)
2838				return USB_SSP_GEN_2x2;
2839
2840			if (mantissa >= 5 && lanes == 2)
2841				return USB_SSP_GEN_1x2;
2842
2843			goto out;
2844		}
2845	}
2846
2847out:
2848	return USB_SSP_GEN_UNKNOWN;
2849}
2850
 
 
 
 
 
 
 
 
 
 
 
2851#ifdef CONFIG_USB_FEW_INIT_RETRIES
2852#define PORT_RESET_TRIES	2
2853#define SET_ADDRESS_TRIES	1
2854#define GET_DESCRIPTOR_TRIES	1
2855#define GET_MAXPACKET0_TRIES	1
2856#define PORT_INIT_TRIES		4
2857
2858#else
2859#define PORT_RESET_TRIES	5
2860#define SET_ADDRESS_TRIES	2
2861#define GET_DESCRIPTOR_TRIES	2
2862#define GET_MAXPACKET0_TRIES	3
2863#define PORT_INIT_TRIES		4
2864#endif	/* CONFIG_USB_FEW_INIT_RETRIES */
2865
2866#define DETECT_DISCONNECT_TRIES 5
2867
2868#define HUB_ROOT_RESET_TIME	60	/* times are in msec */
2869#define HUB_SHORT_RESET_TIME	10
2870#define HUB_BH_RESET_TIME	50
2871#define HUB_LONG_RESET_TIME	200
2872#define HUB_RESET_TIMEOUT	800
2873
2874static bool use_new_scheme(struct usb_device *udev, int retry,
2875			   struct usb_port *port_dev)
2876{
2877	int old_scheme_first_port =
2878		(port_dev->quirks & USB_PORT_QUIRK_OLD_SCHEME) ||
2879		old_scheme_first;
2880
2881	/*
2882	 * "New scheme" enumeration causes an extra state transition to be
2883	 * exposed to an xhci host and causes USB3 devices to receive control
2884	 * commands in the default state.  This has been seen to cause
2885	 * enumeration failures, so disable this enumeration scheme for USB3
2886	 * devices.
2887	 */
2888	if (udev->speed >= USB_SPEED_SUPER)
2889		return false;
2890
2891	/*
2892	 * If use_both_schemes is set, use the first scheme (whichever
2893	 * it is) for the larger half of the retries, then use the other
2894	 * scheme.  Otherwise, use the first scheme for all the retries.
2895	 */
2896	if (use_both_schemes && retry >= (PORT_INIT_TRIES + 1) / 2)
2897		return old_scheme_first_port;	/* Second half */
2898	return !old_scheme_first_port;		/* First half or all */
2899}
2900
2901/* Is a USB 3.0 port in the Inactive or Compliance Mode state?
2902 * Port warm reset is required to recover
2903 */
2904static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
2905		u16 portstatus)
2906{
2907	u16 link_state;
2908
2909	if (!hub_is_superspeed(hub->hdev))
2910		return false;
2911
2912	if (test_bit(port1, hub->warm_reset_bits))
2913		return true;
2914
2915	link_state = portstatus & USB_PORT_STAT_LINK_STATE;
2916	return link_state == USB_SS_PORT_LS_SS_INACTIVE
2917		|| link_state == USB_SS_PORT_LS_COMP_MOD;
2918}
2919
2920static int hub_port_wait_reset(struct usb_hub *hub, int port1,
2921			struct usb_device *udev, unsigned int delay, bool warm)
2922{
2923	int delay_time, ret;
2924	u16 portstatus;
2925	u16 portchange;
2926	u32 ext_portstatus = 0;
2927
2928	for (delay_time = 0;
2929			delay_time < HUB_RESET_TIMEOUT;
2930			delay_time += delay) {
2931		/* wait to give the device a chance to reset */
2932		msleep(delay);
2933
2934		/* read and decode port status */
2935		if (hub_is_superspeedplus(hub->hdev))
2936			ret = hub_ext_port_status(hub, port1,
2937						  HUB_EXT_PORT_STATUS,
2938						  &portstatus, &portchange,
2939						  &ext_portstatus);
2940		else
2941			ret = usb_hub_port_status(hub, port1, &portstatus,
2942					      &portchange);
2943		if (ret < 0)
2944			return ret;
2945
2946		/*
2947		 * The port state is unknown until the reset completes.
2948		 *
2949		 * On top of that, some chips may require additional time
2950		 * to re-establish a connection after the reset is complete,
2951		 * so also wait for the connection to be re-established.
2952		 */
2953		if (!(portstatus & USB_PORT_STAT_RESET) &&
2954		    (portstatus & USB_PORT_STAT_CONNECTION))
2955			break;
2956
2957		/* switch to the long delay after two short delay failures */
2958		if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
2959			delay = HUB_LONG_RESET_TIME;
2960
2961		dev_dbg(&hub->ports[port1 - 1]->dev,
2962				"not %sreset yet, waiting %dms\n",
2963				warm ? "warm " : "", delay);
2964	}
2965
2966	if ((portstatus & USB_PORT_STAT_RESET))
2967		return -EBUSY;
2968
2969	if (hub_port_warm_reset_required(hub, port1, portstatus))
2970		return -ENOTCONN;
2971
2972	/* Device went away? */
2973	if (!(portstatus & USB_PORT_STAT_CONNECTION))
2974		return -ENOTCONN;
2975
2976	/* Retry if connect change is set but status is still connected.
2977	 * A USB 3.0 connection may bounce if multiple warm resets were issued,
2978	 * but the device may have successfully re-connected. Ignore it.
2979	 */
2980	if (!hub_is_superspeed(hub->hdev) &&
2981	    (portchange & USB_PORT_STAT_C_CONNECTION)) {
2982		usb_clear_port_feature(hub->hdev, port1,
2983				       USB_PORT_FEAT_C_CONNECTION);
2984		return -EAGAIN;
2985	}
2986
2987	if (!(portstatus & USB_PORT_STAT_ENABLE))
2988		return -EBUSY;
2989
2990	if (!udev)
2991		return 0;
2992
2993	if (hub_is_superspeedplus(hub->hdev)) {
2994		/* extended portstatus Rx and Tx lane count are zero based */
2995		udev->rx_lanes = USB_EXT_PORT_RX_LANES(ext_portstatus) + 1;
2996		udev->tx_lanes = USB_EXT_PORT_TX_LANES(ext_portstatus) + 1;
2997		udev->ssp_rate = get_port_ssp_rate(hub->hdev, ext_portstatus);
2998	} else {
2999		udev->rx_lanes = 1;
3000		udev->tx_lanes = 1;
3001		udev->ssp_rate = USB_SSP_GEN_UNKNOWN;
3002	}
3003	if (udev->ssp_rate != USB_SSP_GEN_UNKNOWN)
 
 
3004		udev->speed = USB_SPEED_SUPER_PLUS;
3005	else if (hub_is_superspeed(hub->hdev))
3006		udev->speed = USB_SPEED_SUPER;
3007	else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
3008		udev->speed = USB_SPEED_HIGH;
3009	else if (portstatus & USB_PORT_STAT_LOW_SPEED)
3010		udev->speed = USB_SPEED_LOW;
3011	else
3012		udev->speed = USB_SPEED_FULL;
3013	return 0;
3014}
3015
3016/* Handle port reset and port warm(BH) reset (for USB3 protocol ports) */
3017static int hub_port_reset(struct usb_hub *hub, int port1,
3018			struct usb_device *udev, unsigned int delay, bool warm)
3019{
3020	int i, status;
3021	u16 portchange, portstatus;
3022	struct usb_port *port_dev = hub->ports[port1 - 1];
3023	int reset_recovery_time;
3024
3025	if (!hub_is_superspeed(hub->hdev)) {
3026		if (warm) {
3027			dev_err(hub->intfdev, "only USB3 hub support "
3028						"warm reset\n");
3029			return -EINVAL;
3030		}
3031		/* Block EHCI CF initialization during the port reset.
3032		 * Some companion controllers don't like it when they mix.
3033		 */
3034		down_read(&ehci_cf_port_reset_rwsem);
3035	} else if (!warm) {
3036		/*
3037		 * If the caller hasn't explicitly requested a warm reset,
3038		 * double check and see if one is needed.
3039		 */
3040		if (usb_hub_port_status(hub, port1, &portstatus,
3041					&portchange) == 0)
3042			if (hub_port_warm_reset_required(hub, port1,
3043							portstatus))
3044				warm = true;
3045	}
3046	clear_bit(port1, hub->warm_reset_bits);
3047
3048	/* Reset the port */
3049	for (i = 0; i < PORT_RESET_TRIES; i++) {
3050		status = set_port_feature(hub->hdev, port1, (warm ?
3051					USB_PORT_FEAT_BH_PORT_RESET :
3052					USB_PORT_FEAT_RESET));
3053		if (status == -ENODEV) {
3054			;	/* The hub is gone */
3055		} else if (status) {
3056			dev_err(&port_dev->dev,
3057					"cannot %sreset (err = %d)\n",
3058					warm ? "warm " : "", status);
3059		} else {
3060			status = hub_port_wait_reset(hub, port1, udev, delay,
3061								warm);
3062			if (status && status != -ENOTCONN && status != -ENODEV)
3063				dev_dbg(hub->intfdev,
3064						"port_wait_reset: err = %d\n",
3065						status);
3066		}
3067
3068		/*
3069		 * Check for disconnect or reset, and bail out after several
3070		 * reset attempts to avoid warm reset loop.
3071		 */
3072		if (status == 0 || status == -ENOTCONN || status == -ENODEV ||
3073		    (status == -EBUSY && i == PORT_RESET_TRIES - 1)) {
3074			usb_clear_port_feature(hub->hdev, port1,
3075					USB_PORT_FEAT_C_RESET);
3076
3077			if (!hub_is_superspeed(hub->hdev))
3078				goto done;
3079
3080			usb_clear_port_feature(hub->hdev, port1,
3081					USB_PORT_FEAT_C_BH_PORT_RESET);
3082			usb_clear_port_feature(hub->hdev, port1,
3083					USB_PORT_FEAT_C_PORT_LINK_STATE);
3084
3085			if (udev)
3086				usb_clear_port_feature(hub->hdev, port1,
3087					USB_PORT_FEAT_C_CONNECTION);
3088
3089			/*
3090			 * If a USB 3.0 device migrates from reset to an error
3091			 * state, re-issue the warm reset.
3092			 */
3093			if (usb_hub_port_status(hub, port1,
3094					&portstatus, &portchange) < 0)
3095				goto done;
3096
3097			if (!hub_port_warm_reset_required(hub, port1,
3098					portstatus))
3099				goto done;
3100
3101			/*
3102			 * If the port is in SS.Inactive or Compliance Mode, the
3103			 * hot or warm reset failed.  Try another warm reset.
3104			 */
3105			if (!warm) {
3106				dev_dbg(&port_dev->dev,
3107						"hot reset failed, warm reset\n");
3108				warm = true;
3109			}
3110		}
3111
3112		dev_dbg(&port_dev->dev,
3113				"not enabled, trying %sreset again...\n",
3114				warm ? "warm " : "");
3115		delay = HUB_LONG_RESET_TIME;
3116	}
3117
3118	dev_err(&port_dev->dev, "Cannot enable. Maybe the USB cable is bad?\n");
3119
3120done:
3121	if (status == 0) {
3122		if (port_dev->quirks & USB_PORT_QUIRK_FAST_ENUM)
3123			usleep_range(10000, 12000);
3124		else {
3125			/* TRSTRCY = 10 ms; plus some extra */
3126			reset_recovery_time = 10 + 40;
3127
3128			/* Hub needs extra delay after resetting its port. */
3129			if (hub->hdev->quirks & USB_QUIRK_HUB_SLOW_RESET)
3130				reset_recovery_time += 100;
3131
3132			msleep(reset_recovery_time);
3133		}
3134
3135		if (udev) {
3136			struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3137
3138			update_devnum(udev, 0);
3139			/* The xHC may think the device is already reset,
3140			 * so ignore the status.
3141			 */
3142			if (hcd->driver->reset_device)
3143				hcd->driver->reset_device(hcd, udev);
3144
3145			usb_set_device_state(udev, USB_STATE_DEFAULT);
3146		}
3147	} else {
3148		if (udev)
3149			usb_set_device_state(udev, USB_STATE_NOTATTACHED);
3150	}
3151
3152	if (!hub_is_superspeed(hub->hdev))
3153		up_read(&ehci_cf_port_reset_rwsem);
3154
3155	return status;
3156}
3157
3158/*
3159 * hub_port_stop_enumerate - stop USB enumeration or ignore port events
3160 * @hub: target hub
3161 * @port1: port num of the port
3162 * @retries: port retries number of hub_port_init()
3163 *
3164 * Return:
3165 *    true: ignore port actions/events or give up connection attempts.
3166 *    false: keep original behavior.
3167 *
3168 * This function will be based on retries to check whether the port which is
3169 * marked with early_stop attribute would stop enumeration or ignore events.
3170 *
3171 * Note:
3172 * This function didn't change anything if early_stop is not set, and it will
3173 * prevent all connection attempts when early_stop is set and the attempts of
3174 * the port are more than 1.
3175 */
3176static bool hub_port_stop_enumerate(struct usb_hub *hub, int port1, int retries)
3177{
3178	struct usb_port *port_dev = hub->ports[port1 - 1];
3179
3180	if (port_dev->early_stop) {
3181		if (port_dev->ignore_event)
3182			return true;
3183
3184		/*
3185		 * We want unsuccessful attempts to fail quickly.
3186		 * Since some devices may need one failure during
3187		 * port initialization, we allow two tries but no
3188		 * more.
3189		 */
3190		if (retries < 2)
3191			return false;
3192
3193		port_dev->ignore_event = 1;
3194	} else
3195		port_dev->ignore_event = 0;
3196
3197	return port_dev->ignore_event;
3198}
3199
3200/* Check if a port is power on */
3201int usb_port_is_power_on(struct usb_hub *hub, unsigned int portstatus)
3202{
3203	int ret = 0;
3204
3205	if (hub_is_superspeed(hub->hdev)) {
3206		if (portstatus & USB_SS_PORT_STAT_POWER)
3207			ret = 1;
3208	} else {
3209		if (portstatus & USB_PORT_STAT_POWER)
3210			ret = 1;
3211	}
3212
3213	return ret;
3214}
3215
3216static void usb_lock_port(struct usb_port *port_dev)
3217		__acquires(&port_dev->status_lock)
3218{
3219	mutex_lock(&port_dev->status_lock);
3220	__acquire(&port_dev->status_lock);
3221}
3222
3223static void usb_unlock_port(struct usb_port *port_dev)
3224		__releases(&port_dev->status_lock)
3225{
3226	mutex_unlock(&port_dev->status_lock);
3227	__release(&port_dev->status_lock);
3228}
3229
3230#ifdef	CONFIG_PM
3231
3232/* Check if a port is suspended(USB2.0 port) or in U3 state(USB3.0 port) */
3233static int port_is_suspended(struct usb_hub *hub, unsigned portstatus)
3234{
3235	int ret = 0;
3236
3237	if (hub_is_superspeed(hub->hdev)) {
3238		if ((portstatus & USB_PORT_STAT_LINK_STATE)
3239				== USB_SS_PORT_LS_U3)
3240			ret = 1;
3241	} else {
3242		if (portstatus & USB_PORT_STAT_SUSPEND)
3243			ret = 1;
3244	}
3245
3246	return ret;
3247}
3248
3249/* Determine whether the device on a port is ready for a normal resume,
3250 * is ready for a reset-resume, or should be disconnected.
3251 */
3252static int check_port_resume_type(struct usb_device *udev,
3253		struct usb_hub *hub, int port1,
3254		int status, u16 portchange, u16 portstatus)
3255{
3256	struct usb_port *port_dev = hub->ports[port1 - 1];
3257	int retries = 3;
3258
3259 retry:
3260	/* Is a warm reset needed to recover the connection? */
3261	if (status == 0 && udev->reset_resume
3262		&& hub_port_warm_reset_required(hub, port1, portstatus)) {
3263		/* pass */;
3264	}
3265	/* Is the device still present? */
3266	else if (status || port_is_suspended(hub, portstatus) ||
3267			!usb_port_is_power_on(hub, portstatus)) {
3268		if (status >= 0)
3269			status = -ENODEV;
3270	} else if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
3271		if (retries--) {
3272			usleep_range(200, 300);
3273			status = usb_hub_port_status(hub, port1, &portstatus,
3274							     &portchange);
3275			goto retry;
3276		}
3277		status = -ENODEV;
3278	}
3279
3280	/* Can't do a normal resume if the port isn't enabled,
3281	 * so try a reset-resume instead.
3282	 */
3283	else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
3284		if (udev->persist_enabled)
3285			udev->reset_resume = 1;
3286		else
3287			status = -ENODEV;
3288	}
3289
3290	if (status) {
3291		dev_dbg(&port_dev->dev, "status %04x.%04x after resume, %d\n",
3292				portchange, portstatus, status);
3293	} else if (udev->reset_resume) {
3294
3295		/* Late port handoff can set status-change bits */
3296		if (portchange & USB_PORT_STAT_C_CONNECTION)
3297			usb_clear_port_feature(hub->hdev, port1,
3298					USB_PORT_FEAT_C_CONNECTION);
3299		if (portchange & USB_PORT_STAT_C_ENABLE)
3300			usb_clear_port_feature(hub->hdev, port1,
3301					USB_PORT_FEAT_C_ENABLE);
3302
3303		/*
3304		 * Whatever made this reset-resume necessary may have
3305		 * turned on the port1 bit in hub->change_bits.  But after
3306		 * a successful reset-resume we want the bit to be clear;
3307		 * if it was on it would indicate that something happened
3308		 * following the reset-resume.
3309		 */
3310		clear_bit(port1, hub->change_bits);
3311	}
3312
3313	return status;
3314}
3315
3316int usb_disable_ltm(struct usb_device *udev)
3317{
3318	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3319
3320	/* Check if the roothub and device supports LTM. */
3321	if (!usb_device_supports_ltm(hcd->self.root_hub) ||
3322			!usb_device_supports_ltm(udev))
3323		return 0;
3324
3325	/* Clear Feature LTM Enable can only be sent if the device is
3326	 * configured.
3327	 */
3328	if (!udev->actconfig)
3329		return 0;
3330
3331	return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3332			USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
3333			USB_DEVICE_LTM_ENABLE, 0, NULL, 0,
3334			USB_CTRL_SET_TIMEOUT);
3335}
3336EXPORT_SYMBOL_GPL(usb_disable_ltm);
3337
3338void usb_enable_ltm(struct usb_device *udev)
3339{
3340	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3341
3342	/* Check if the roothub and device supports LTM. */
3343	if (!usb_device_supports_ltm(hcd->self.root_hub) ||
3344			!usb_device_supports_ltm(udev))
3345		return;
3346
3347	/* Set Feature LTM Enable can only be sent if the device is
3348	 * configured.
3349	 */
3350	if (!udev->actconfig)
3351		return;
3352
3353	usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3354			USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
3355			USB_DEVICE_LTM_ENABLE, 0, NULL, 0,
3356			USB_CTRL_SET_TIMEOUT);
3357}
3358EXPORT_SYMBOL_GPL(usb_enable_ltm);
3359
3360/*
3361 * usb_enable_remote_wakeup - enable remote wakeup for a device
3362 * @udev: target device
3363 *
3364 * For USB-2 devices: Set the device's remote wakeup feature.
3365 *
3366 * For USB-3 devices: Assume there's only one function on the device and
3367 * enable remote wake for the first interface.  FIXME if the interface
3368 * association descriptor shows there's more than one function.
3369 */
3370static int usb_enable_remote_wakeup(struct usb_device *udev)
3371{
3372	if (udev->speed < USB_SPEED_SUPER)
3373		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3374				USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
3375				USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0,
3376				USB_CTRL_SET_TIMEOUT);
3377	else
3378		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3379				USB_REQ_SET_FEATURE, USB_RECIP_INTERFACE,
3380				USB_INTRF_FUNC_SUSPEND,
3381				USB_INTRF_FUNC_SUSPEND_RW |
3382					USB_INTRF_FUNC_SUSPEND_LP,
3383				NULL, 0, USB_CTRL_SET_TIMEOUT);
3384}
3385
3386/*
3387 * usb_disable_remote_wakeup - disable remote wakeup for a device
3388 * @udev: target device
3389 *
3390 * For USB-2 devices: Clear the device's remote wakeup feature.
3391 *
3392 * For USB-3 devices: Assume there's only one function on the device and
3393 * disable remote wake for the first interface.  FIXME if the interface
3394 * association descriptor shows there's more than one function.
3395 */
3396static int usb_disable_remote_wakeup(struct usb_device *udev)
3397{
3398	if (udev->speed < USB_SPEED_SUPER)
3399		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3400				USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
3401				USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0,
3402				USB_CTRL_SET_TIMEOUT);
3403	else
3404		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3405				USB_REQ_SET_FEATURE, USB_RECIP_INTERFACE,
3406				USB_INTRF_FUNC_SUSPEND,	0, NULL, 0,
3407				USB_CTRL_SET_TIMEOUT);
3408}
3409
3410/* Count of wakeup-enabled devices at or below udev */
3411unsigned usb_wakeup_enabled_descendants(struct usb_device *udev)
3412{
3413	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
3414
3415	return udev->do_remote_wakeup +
3416			(hub ? hub->wakeup_enabled_descendants : 0);
3417}
3418EXPORT_SYMBOL_GPL(usb_wakeup_enabled_descendants);
3419
3420/*
3421 * usb_port_suspend - suspend a usb device's upstream port
3422 * @udev: device that's no longer in active use, not a root hub
3423 * Context: must be able to sleep; device not locked; pm locks held
3424 *
3425 * Suspends a USB device that isn't in active use, conserving power.
3426 * Devices may wake out of a suspend, if anything important happens,
3427 * using the remote wakeup mechanism.  They may also be taken out of
3428 * suspend by the host, using usb_port_resume().  It's also routine
3429 * to disconnect devices while they are suspended.
3430 *
3431 * This only affects the USB hardware for a device; its interfaces
3432 * (and, for hubs, child devices) must already have been suspended.
3433 *
3434 * Selective port suspend reduces power; most suspended devices draw
3435 * less than 500 uA.  It's also used in OTG, along with remote wakeup.
3436 * All devices below the suspended port are also suspended.
3437 *
3438 * Devices leave suspend state when the host wakes them up.  Some devices
3439 * also support "remote wakeup", where the device can activate the USB
3440 * tree above them to deliver data, such as a keypress or packet.  In
3441 * some cases, this wakes the USB host.
3442 *
3443 * Suspending OTG devices may trigger HNP, if that's been enabled
3444 * between a pair of dual-role devices.  That will change roles, such
3445 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
3446 *
3447 * Devices on USB hub ports have only one "suspend" state, corresponding
3448 * to ACPI D2, "may cause the device to lose some context".
3449 * State transitions include:
3450 *
3451 *   - suspend, resume ... when the VBUS power link stays live
3452 *   - suspend, disconnect ... VBUS lost
3453 *
3454 * Once VBUS drop breaks the circuit, the port it's using has to go through
3455 * normal re-enumeration procedures, starting with enabling VBUS power.
3456 * Other than re-initializing the hub (plug/unplug, except for root hubs),
3457 * Linux (2.6) currently has NO mechanisms to initiate that:  no hub_wq
3458 * timer, no SRP, no requests through sysfs.
3459 *
3460 * If Runtime PM isn't enabled or used, non-SuperSpeed devices may not get
3461 * suspended until their bus goes into global suspend (i.e., the root
3462 * hub is suspended).  Nevertheless, we change @udev->state to
3463 * USB_STATE_SUSPENDED as this is the device's "logical" state.  The actual
3464 * upstream port setting is stored in @udev->port_is_suspended.
3465 *
3466 * Returns 0 on success, else negative errno.
3467 */
3468int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
3469{
3470	struct usb_hub	*hub = usb_hub_to_struct_hub(udev->parent);
3471	struct usb_port *port_dev = hub->ports[udev->portnum - 1];
3472	int		port1 = udev->portnum;
3473	int		status;
3474	bool		really_suspend = true;
3475
3476	usb_lock_port(port_dev);
3477
3478	/* enable remote wakeup when appropriate; this lets the device
3479	 * wake up the upstream hub (including maybe the root hub).
3480	 *
3481	 * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
3482	 * we don't explicitly enable it here.
3483	 */
3484	if (udev->do_remote_wakeup) {
3485		status = usb_enable_remote_wakeup(udev);
3486		if (status) {
3487			dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
3488					status);
3489			/* bail if autosuspend is requested */
3490			if (PMSG_IS_AUTO(msg))
3491				goto err_wakeup;
3492		}
3493	}
3494
3495	/* disable USB2 hardware LPM */
3496	usb_disable_usb2_hardware_lpm(udev);
3497
3498	if (usb_disable_ltm(udev)) {
3499		dev_err(&udev->dev, "Failed to disable LTM before suspend\n");
3500		status = -ENOMEM;
3501		if (PMSG_IS_AUTO(msg))
3502			goto err_ltm;
3503	}
3504
3505	/* see 7.1.7.6 */
3506	if (hub_is_superspeed(hub->hdev))
3507		status = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_U3);
3508
3509	/*
3510	 * For system suspend, we do not need to enable the suspend feature
3511	 * on individual USB-2 ports.  The devices will automatically go
3512	 * into suspend a few ms after the root hub stops sending packets.
3513	 * The USB 2.0 spec calls this "global suspend".
3514	 *
3515	 * However, many USB hubs have a bug: They don't relay wakeup requests
3516	 * from a downstream port if the port's suspend feature isn't on.
3517	 * Therefore we will turn on the suspend feature if udev or any of its
3518	 * descendants is enabled for remote wakeup.
3519	 */
3520	else if (PMSG_IS_AUTO(msg) || usb_wakeup_enabled_descendants(udev) > 0)
3521		status = set_port_feature(hub->hdev, port1,
3522				USB_PORT_FEAT_SUSPEND);
3523	else {
3524		really_suspend = false;
3525		status = 0;
3526	}
3527	if (status) {
3528		/* Check if the port has been suspended for the timeout case
3529		 * to prevent the suspended port from incorrect handling.
3530		 */
3531		if (status == -ETIMEDOUT) {
3532			int ret;
3533			u16 portstatus, portchange;
3534
3535			portstatus = portchange = 0;
3536			ret = usb_hub_port_status(hub, port1, &portstatus,
3537					&portchange);
3538
3539			dev_dbg(&port_dev->dev,
3540				"suspend timeout, status %04x\n", portstatus);
3541
3542			if (ret == 0 && port_is_suspended(hub, portstatus)) {
3543				status = 0;
3544				goto suspend_done;
3545			}
3546		}
3547
3548		dev_dbg(&port_dev->dev, "can't suspend, status %d\n", status);
3549
3550		/* Try to enable USB3 LTM again */
3551		usb_enable_ltm(udev);
3552 err_ltm:
3553		/* Try to enable USB2 hardware LPM again */
3554		usb_enable_usb2_hardware_lpm(udev);
3555
3556		if (udev->do_remote_wakeup)
3557			(void) usb_disable_remote_wakeup(udev);
3558 err_wakeup:
3559
3560		/* System sleep transitions should never fail */
3561		if (!PMSG_IS_AUTO(msg))
3562			status = 0;
3563	} else {
3564 suspend_done:
3565		dev_dbg(&udev->dev, "usb %ssuspend, wakeup %d\n",
3566				(PMSG_IS_AUTO(msg) ? "auto-" : ""),
3567				udev->do_remote_wakeup);
3568		if (really_suspend) {
3569			udev->port_is_suspended = 1;
3570
3571			/* device has up to 10 msec to fully suspend */
3572			msleep(10);
3573		}
3574		usb_set_device_state(udev, USB_STATE_SUSPENDED);
3575	}
3576
3577	if (status == 0 && !udev->do_remote_wakeup && udev->persist_enabled
3578			&& test_and_clear_bit(port1, hub->child_usage_bits))
3579		pm_runtime_put_sync(&port_dev->dev);
3580
3581	usb_mark_last_busy(hub->hdev);
3582
3583	usb_unlock_port(port_dev);
3584	return status;
3585}
3586
3587/*
3588 * If the USB "suspend" state is in use (rather than "global suspend"),
3589 * many devices will be individually taken out of suspend state using
3590 * special "resume" signaling.  This routine kicks in shortly after
3591 * hardware resume signaling is finished, either because of selective
3592 * resume (by host) or remote wakeup (by device) ... now see what changed
3593 * in the tree that's rooted at this device.
3594 *
3595 * If @udev->reset_resume is set then the device is reset before the
3596 * status check is done.
3597 */
3598static int finish_port_resume(struct usb_device *udev)
3599{
3600	int	status = 0;
3601	u16	devstatus = 0;
3602
3603	/* caller owns the udev device lock */
3604	dev_dbg(&udev->dev, "%s\n",
3605		udev->reset_resume ? "finish reset-resume" : "finish resume");
3606
3607	/* usb ch9 identifies four variants of SUSPENDED, based on what
3608	 * state the device resumes to.  Linux currently won't see the
3609	 * first two on the host side; they'd be inside hub_port_init()
3610	 * during many timeouts, but hub_wq can't suspend until later.
3611	 */
3612	usb_set_device_state(udev, udev->actconfig
3613			? USB_STATE_CONFIGURED
3614			: USB_STATE_ADDRESS);
3615
3616	/* 10.5.4.5 says not to reset a suspended port if the attached
3617	 * device is enabled for remote wakeup.  Hence the reset
3618	 * operation is carried out here, after the port has been
3619	 * resumed.
3620	 */
3621	if (udev->reset_resume) {
3622		/*
3623		 * If the device morphs or switches modes when it is reset,
3624		 * we don't want to perform a reset-resume.  We'll fail the
3625		 * resume, which will cause a logical disconnect, and then
3626		 * the device will be rediscovered.
3627		 */
3628 retry_reset_resume:
3629		if (udev->quirks & USB_QUIRK_RESET)
3630			status = -ENODEV;
3631		else
3632			status = usb_reset_and_verify_device(udev);
3633	}
3634
3635	/* 10.5.4.5 says be sure devices in the tree are still there.
3636	 * For now let's assume the device didn't go crazy on resume,
3637	 * and device drivers will know about any resume quirks.
3638	 */
3639	if (status == 0) {
3640		devstatus = 0;
3641		status = usb_get_std_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
3642
3643		/* If a normal resume failed, try doing a reset-resume */
3644		if (status && !udev->reset_resume && udev->persist_enabled) {
3645			dev_dbg(&udev->dev, "retry with reset-resume\n");
3646			udev->reset_resume = 1;
3647			goto retry_reset_resume;
3648		}
3649	}
3650
3651	if (status) {
3652		dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
3653				status);
3654	/*
3655	 * There are a few quirky devices which violate the standard
3656	 * by claiming to have remote wakeup enabled after a reset,
3657	 * which crash if the feature is cleared, hence check for
3658	 * udev->reset_resume
3659	 */
3660	} else if (udev->actconfig && !udev->reset_resume) {
3661		if (udev->speed < USB_SPEED_SUPER) {
3662			if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
3663				status = usb_disable_remote_wakeup(udev);
3664		} else {
3665			status = usb_get_std_status(udev, USB_RECIP_INTERFACE, 0,
3666					&devstatus);
3667			if (!status && devstatus & (USB_INTRF_STAT_FUNC_RW_CAP
3668					| USB_INTRF_STAT_FUNC_RW))
3669				status = usb_disable_remote_wakeup(udev);
3670		}
3671
3672		if (status)
3673			dev_dbg(&udev->dev,
3674				"disable remote wakeup, status %d\n",
3675				status);
3676		status = 0;
3677	}
3678	return status;
3679}
3680
3681/*
3682 * There are some SS USB devices which take longer time for link training.
3683 * XHCI specs 4.19.4 says that when Link training is successful, port
3684 * sets CCS bit to 1. So if SW reads port status before successful link
3685 * training, then it will not find device to be present.
3686 * USB Analyzer log with such buggy devices show that in some cases
3687 * device switch on the RX termination after long delay of host enabling
3688 * the VBUS. In few other cases it has been seen that device fails to
3689 * negotiate link training in first attempt. It has been
3690 * reported till now that few devices take as long as 2000 ms to train
3691 * the link after host enabling its VBUS and termination. Following
3692 * routine implements a 2000 ms timeout for link training. If in a case
3693 * link trains before timeout, loop will exit earlier.
3694 *
3695 * There are also some 2.0 hard drive based devices and 3.0 thumb
3696 * drives that, when plugged into a 2.0 only port, take a long
3697 * time to set CCS after VBUS enable.
3698 *
3699 * FIXME: If a device was connected before suspend, but was removed
3700 * while system was asleep, then the loop in the following routine will
3701 * only exit at timeout.
3702 *
3703 * This routine should only be called when persist is enabled.
3704 */
3705static int wait_for_connected(struct usb_device *udev,
3706		struct usb_hub *hub, int port1,
3707		u16 *portchange, u16 *portstatus)
3708{
3709	int status = 0, delay_ms = 0;
3710
3711	while (delay_ms < 2000) {
3712		if (status || *portstatus & USB_PORT_STAT_CONNECTION)
3713			break;
3714		if (!usb_port_is_power_on(hub, *portstatus)) {
3715			status = -ENODEV;
3716			break;
3717		}
3718		msleep(20);
3719		delay_ms += 20;
3720		status = usb_hub_port_status(hub, port1, portstatus, portchange);
3721	}
3722	dev_dbg(&udev->dev, "Waited %dms for CONNECT\n", delay_ms);
3723	return status;
3724}
3725
3726/*
3727 * usb_port_resume - re-activate a suspended usb device's upstream port
3728 * @udev: device to re-activate, not a root hub
3729 * Context: must be able to sleep; device not locked; pm locks held
3730 *
3731 * This will re-activate the suspended device, increasing power usage
3732 * while letting drivers communicate again with its endpoints.
3733 * USB resume explicitly guarantees that the power session between
3734 * the host and the device is the same as it was when the device
3735 * suspended.
3736 *
3737 * If @udev->reset_resume is set then this routine won't check that the
3738 * port is still enabled.  Furthermore, finish_port_resume() above will
3739 * reset @udev.  The end result is that a broken power session can be
3740 * recovered and @udev will appear to persist across a loss of VBUS power.
3741 *
3742 * For example, if a host controller doesn't maintain VBUS suspend current
3743 * during a system sleep or is reset when the system wakes up, all the USB
3744 * power sessions below it will be broken.  This is especially troublesome
3745 * for mass-storage devices containing mounted filesystems, since the
3746 * device will appear to have disconnected and all the memory mappings
3747 * to it will be lost.  Using the USB_PERSIST facility, the device can be
3748 * made to appear as if it had not disconnected.
3749 *
3750 * This facility can be dangerous.  Although usb_reset_and_verify_device() makes
3751 * every effort to insure that the same device is present after the
3752 * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
3753 * quite possible for a device to remain unaltered but its media to be
3754 * changed.  If the user replaces a flash memory card while the system is
3755 * asleep, he will have only himself to blame when the filesystem on the
3756 * new card is corrupted and the system crashes.
3757 *
3758 * Returns 0 on success, else negative errno.
3759 */
3760int usb_port_resume(struct usb_device *udev, pm_message_t msg)
3761{
3762	struct usb_hub	*hub = usb_hub_to_struct_hub(udev->parent);
3763	struct usb_port *port_dev = hub->ports[udev->portnum  - 1];
3764	int		port1 = udev->portnum;
3765	int		status;
3766	u16		portchange, portstatus;
3767
3768	if (!test_and_set_bit(port1, hub->child_usage_bits)) {
3769		status = pm_runtime_resume_and_get(&port_dev->dev);
3770		if (status < 0) {
3771			dev_dbg(&udev->dev, "can't resume usb port, status %d\n",
3772					status);
3773			return status;
3774		}
3775	}
3776
3777	usb_lock_port(port_dev);
3778
3779	/* Skip the initial Clear-Suspend step for a remote wakeup */
3780	status = usb_hub_port_status(hub, port1, &portstatus, &portchange);
3781	if (status == 0 && !port_is_suspended(hub, portstatus)) {
3782		if (portchange & USB_PORT_STAT_C_SUSPEND)
3783			pm_wakeup_event(&udev->dev, 0);
3784		goto SuspendCleared;
3785	}
3786
3787	/* see 7.1.7.7; affects power usage, but not budgeting */
3788	if (hub_is_superspeed(hub->hdev))
3789		status = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_U0);
3790	else
3791		status = usb_clear_port_feature(hub->hdev,
3792				port1, USB_PORT_FEAT_SUSPEND);
3793	if (status) {
3794		dev_dbg(&port_dev->dev, "can't resume, status %d\n", status);
3795	} else {
3796		/* drive resume for USB_RESUME_TIMEOUT msec */
3797		dev_dbg(&udev->dev, "usb %sresume\n",
3798				(PMSG_IS_AUTO(msg) ? "auto-" : ""));
3799		msleep(USB_RESUME_TIMEOUT);
3800
3801		/* Virtual root hubs can trigger on GET_PORT_STATUS to
3802		 * stop resume signaling.  Then finish the resume
3803		 * sequence.
3804		 */
3805		status = usb_hub_port_status(hub, port1, &portstatus, &portchange);
3806	}
3807
3808 SuspendCleared:
3809	if (status == 0) {
3810		udev->port_is_suspended = 0;
3811		if (hub_is_superspeed(hub->hdev)) {
3812			if (portchange & USB_PORT_STAT_C_LINK_STATE)
3813				usb_clear_port_feature(hub->hdev, port1,
3814					USB_PORT_FEAT_C_PORT_LINK_STATE);
3815		} else {
3816			if (portchange & USB_PORT_STAT_C_SUSPEND)
3817				usb_clear_port_feature(hub->hdev, port1,
3818						USB_PORT_FEAT_C_SUSPEND);
3819		}
3820
3821		/* TRSMRCY = 10 msec */
3822		msleep(10);
3823	}
3824
3825	if (udev->persist_enabled)
3826		status = wait_for_connected(udev, hub, port1, &portchange,
3827				&portstatus);
3828
3829	status = check_port_resume_type(udev,
3830			hub, port1, status, portchange, portstatus);
3831	if (status == 0)
3832		status = finish_port_resume(udev);
3833	if (status < 0) {
3834		dev_dbg(&udev->dev, "can't resume, status %d\n", status);
3835		hub_port_logical_disconnect(hub, port1);
3836	} else  {
3837		/* Try to enable USB2 hardware LPM */
3838		usb_enable_usb2_hardware_lpm(udev);
3839
3840		/* Try to enable USB3 LTM */
3841		usb_enable_ltm(udev);
3842	}
3843
3844	usb_unlock_port(port_dev);
3845
3846	return status;
3847}
3848
3849int usb_remote_wakeup(struct usb_device *udev)
3850{
3851	int	status = 0;
3852
3853	usb_lock_device(udev);
3854	if (udev->state == USB_STATE_SUSPENDED) {
3855		dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
3856		status = usb_autoresume_device(udev);
3857		if (status == 0) {
3858			/* Let the drivers do their thing, then... */
3859			usb_autosuspend_device(udev);
3860		}
3861	}
3862	usb_unlock_device(udev);
3863	return status;
3864}
3865
3866/* Returns 1 if there was a remote wakeup and a connect status change. */
3867static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
3868		u16 portstatus, u16 portchange)
3869		__must_hold(&port_dev->status_lock)
3870{
3871	struct usb_port *port_dev = hub->ports[port - 1];
3872	struct usb_device *hdev;
3873	struct usb_device *udev;
3874	int connect_change = 0;
3875	u16 link_state;
3876	int ret;
3877
3878	hdev = hub->hdev;
3879	udev = port_dev->child;
3880	if (!hub_is_superspeed(hdev)) {
3881		if (!(portchange & USB_PORT_STAT_C_SUSPEND))
3882			return 0;
3883		usb_clear_port_feature(hdev, port, USB_PORT_FEAT_C_SUSPEND);
3884	} else {
3885		link_state = portstatus & USB_PORT_STAT_LINK_STATE;
3886		if (!udev || udev->state != USB_STATE_SUSPENDED ||
3887				(link_state != USB_SS_PORT_LS_U0 &&
3888				 link_state != USB_SS_PORT_LS_U1 &&
3889				 link_state != USB_SS_PORT_LS_U2))
3890			return 0;
3891	}
3892
3893	if (udev) {
3894		/* TRSMRCY = 10 msec */
3895		msleep(10);
3896
3897		usb_unlock_port(port_dev);
3898		ret = usb_remote_wakeup(udev);
3899		usb_lock_port(port_dev);
3900		if (ret < 0)
3901			connect_change = 1;
3902	} else {
3903		ret = -ENODEV;
3904		hub_port_disable(hub, port, 1);
3905	}
3906	dev_dbg(&port_dev->dev, "resume, status %d\n", ret);
3907	return connect_change;
3908}
3909
3910static int check_ports_changed(struct usb_hub *hub)
3911{
3912	int port1;
3913
3914	for (port1 = 1; port1 <= hub->hdev->maxchild; ++port1) {
3915		u16 portstatus, portchange;
3916		int status;
3917
3918		status = usb_hub_port_status(hub, port1, &portstatus, &portchange);
3919		if (!status && portchange)
3920			return 1;
3921	}
3922	return 0;
3923}
3924
3925static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
3926{
3927	struct usb_hub		*hub = usb_get_intfdata(intf);
3928	struct usb_device	*hdev = hub->hdev;
3929	unsigned		port1;
3930
3931	/*
3932	 * Warn if children aren't already suspended.
3933	 * Also, add up the number of wakeup-enabled descendants.
3934	 */
3935	hub->wakeup_enabled_descendants = 0;
3936	for (port1 = 1; port1 <= hdev->maxchild; port1++) {
3937		struct usb_port *port_dev = hub->ports[port1 - 1];
3938		struct usb_device *udev = port_dev->child;
3939
3940		if (udev && udev->can_submit) {
3941			dev_warn(&port_dev->dev, "device %s not suspended yet\n",
3942					dev_name(&udev->dev));
3943			if (PMSG_IS_AUTO(msg))
3944				return -EBUSY;
3945		}
3946		if (udev)
3947			hub->wakeup_enabled_descendants +=
3948					usb_wakeup_enabled_descendants(udev);
3949	}
3950
3951	if (hdev->do_remote_wakeup && hub->quirk_check_port_auto_suspend) {
3952		/* check if there are changes pending on hub ports */
3953		if (check_ports_changed(hub)) {
3954			if (PMSG_IS_AUTO(msg))
3955				return -EBUSY;
3956			pm_wakeup_event(&hdev->dev, 2000);
3957		}
3958	}
3959
3960	if (hub_is_superspeed(hdev) && hdev->do_remote_wakeup) {
3961		/* Enable hub to send remote wakeup for all ports. */
3962		for (port1 = 1; port1 <= hdev->maxchild; port1++) {
3963			set_port_feature(hdev,
3964					 port1 |
3965					 USB_PORT_FEAT_REMOTE_WAKE_CONNECT |
3966					 USB_PORT_FEAT_REMOTE_WAKE_DISCONNECT |
3967					 USB_PORT_FEAT_REMOTE_WAKE_OVER_CURRENT,
3968					 USB_PORT_FEAT_REMOTE_WAKE_MASK);
3969		}
3970	}
3971
3972	dev_dbg(&intf->dev, "%s\n", __func__);
3973
3974	/* stop hub_wq and related activity */
3975	hub_quiesce(hub, HUB_SUSPEND);
3976	return 0;
3977}
3978
3979/* Report wakeup requests from the ports of a resuming root hub */
3980static void report_wakeup_requests(struct usb_hub *hub)
3981{
3982	struct usb_device	*hdev = hub->hdev;
3983	struct usb_device	*udev;
3984	struct usb_hcd		*hcd;
3985	unsigned long		resuming_ports;
3986	int			i;
3987
3988	if (hdev->parent)
3989		return;		/* Not a root hub */
3990
3991	hcd = bus_to_hcd(hdev->bus);
3992	if (hcd->driver->get_resuming_ports) {
3993
3994		/*
3995		 * The get_resuming_ports() method returns a bitmap (origin 0)
3996		 * of ports which have started wakeup signaling but have not
3997		 * yet finished resuming.  During system resume we will
3998		 * resume all the enabled ports, regardless of any wakeup
3999		 * signals, which means the wakeup requests would be lost.
4000		 * To prevent this, report them to the PM core here.
4001		 */
4002		resuming_ports = hcd->driver->get_resuming_ports(hcd);
4003		for (i = 0; i < hdev->maxchild; ++i) {
4004			if (test_bit(i, &resuming_ports)) {
4005				udev = hub->ports[i]->child;
4006				if (udev)
4007					pm_wakeup_event(&udev->dev, 0);
4008			}
4009		}
4010	}
4011}
4012
4013static int hub_resume(struct usb_interface *intf)
4014{
4015	struct usb_hub *hub = usb_get_intfdata(intf);
4016
4017	dev_dbg(&intf->dev, "%s\n", __func__);
4018	hub_activate(hub, HUB_RESUME);
4019
4020	/*
4021	 * This should be called only for system resume, not runtime resume.
4022	 * We can't tell the difference here, so some wakeup requests will be
4023	 * reported at the wrong time or more than once.  This shouldn't
4024	 * matter much, so long as they do get reported.
4025	 */
4026	report_wakeup_requests(hub);
4027	return 0;
4028}
4029
4030static int hub_reset_resume(struct usb_interface *intf)
4031{
4032	struct usb_hub *hub = usb_get_intfdata(intf);
4033
4034	dev_dbg(&intf->dev, "%s\n", __func__);
4035	hub_activate(hub, HUB_RESET_RESUME);
4036	return 0;
4037}
4038
4039/**
4040 * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
4041 * @rhdev: struct usb_device for the root hub
4042 *
4043 * The USB host controller driver calls this function when its root hub
4044 * is resumed and Vbus power has been interrupted or the controller
4045 * has been reset.  The routine marks @rhdev as having lost power.
4046 * When the hub driver is resumed it will take notice and carry out
4047 * power-session recovery for all the "USB-PERSIST"-enabled child devices;
4048 * the others will be disconnected.
4049 */
4050void usb_root_hub_lost_power(struct usb_device *rhdev)
4051{
4052	dev_notice(&rhdev->dev, "root hub lost power or was reset\n");
4053	rhdev->reset_resume = 1;
4054}
4055EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
4056
4057static const char * const usb3_lpm_names[]  = {
4058	"U0",
4059	"U1",
4060	"U2",
4061	"U3",
4062};
4063
4064/*
4065 * Send a Set SEL control transfer to the device, prior to enabling
4066 * device-initiated U1 or U2.  This lets the device know the exit latencies from
4067 * the time the device initiates a U1 or U2 exit, to the time it will receive a
4068 * packet from the host.
4069 *
4070 * This function will fail if the SEL or PEL values for udev are greater than
4071 * the maximum allowed values for the link state to be enabled.
4072 */
4073static int usb_req_set_sel(struct usb_device *udev)
4074{
4075	struct usb_set_sel_req *sel_values;
4076	unsigned long long u1_sel;
4077	unsigned long long u1_pel;
4078	unsigned long long u2_sel;
4079	unsigned long long u2_pel;
4080	int ret;
4081
4082	if (!udev->parent || udev->speed < USB_SPEED_SUPER || !udev->lpm_capable)
4083		return 0;
4084
4085	/* Convert SEL and PEL stored in ns to us */
4086	u1_sel = DIV_ROUND_UP(udev->u1_params.sel, 1000);
4087	u1_pel = DIV_ROUND_UP(udev->u1_params.pel, 1000);
4088	u2_sel = DIV_ROUND_UP(udev->u2_params.sel, 1000);
4089	u2_pel = DIV_ROUND_UP(udev->u2_params.pel, 1000);
4090
4091	/*
4092	 * Make sure that the calculated SEL and PEL values for the link
4093	 * state we're enabling aren't bigger than the max SEL/PEL
4094	 * value that will fit in the SET SEL control transfer.
4095	 * Otherwise the device would get an incorrect idea of the exit
4096	 * latency for the link state, and could start a device-initiated
4097	 * U1/U2 when the exit latencies are too high.
4098	 */
4099	if (u1_sel > USB3_LPM_MAX_U1_SEL_PEL ||
4100	    u1_pel > USB3_LPM_MAX_U1_SEL_PEL ||
4101	    u2_sel > USB3_LPM_MAX_U2_SEL_PEL ||
4102	    u2_pel > USB3_LPM_MAX_U2_SEL_PEL) {
4103		dev_dbg(&udev->dev, "Device-initiated U1/U2 disabled due to long SEL or PEL\n");
 
 
 
4104		return -EINVAL;
4105	}
4106
4107	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4108	 * usb_enable_lpm() can be called as part of a failed device reset,
4109	 * which may be initiated by an error path of a mass storage driver.
4110	 * Therefore, use GFP_NOIO.
4111	 */
4112	sel_values = kmalloc(sizeof *(sel_values), GFP_NOIO);
4113	if (!sel_values)
4114		return -ENOMEM;
4115
4116	sel_values->u1_sel = u1_sel;
4117	sel_values->u1_pel = u1_pel;
4118	sel_values->u2_sel = cpu_to_le16(u2_sel);
4119	sel_values->u2_pel = cpu_to_le16(u2_pel);
4120
4121	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
4122			USB_REQ_SET_SEL,
4123			USB_RECIP_DEVICE,
4124			0, 0,
4125			sel_values, sizeof *(sel_values),
4126			USB_CTRL_SET_TIMEOUT);
4127	kfree(sel_values);
4128
4129	if (ret > 0)
4130		udev->lpm_devinit_allow = 1;
4131
4132	return ret;
4133}
4134
4135/*
4136 * Enable or disable device-initiated U1 or U2 transitions.
4137 */
4138static int usb_set_device_initiated_lpm(struct usb_device *udev,
4139		enum usb3_link_state state, bool enable)
4140{
4141	int ret;
4142	int feature;
4143
4144	switch (state) {
4145	case USB3_LPM_U1:
4146		feature = USB_DEVICE_U1_ENABLE;
4147		break;
4148	case USB3_LPM_U2:
4149		feature = USB_DEVICE_U2_ENABLE;
4150		break;
4151	default:
4152		dev_warn(&udev->dev, "%s: Can't %s non-U1 or U2 state.\n",
4153				__func__, enable ? "enable" : "disable");
4154		return -EINVAL;
4155	}
4156
4157	if (udev->state != USB_STATE_CONFIGURED) {
4158		dev_dbg(&udev->dev, "%s: Can't %s %s state "
4159				"for unconfigured device.\n",
4160				__func__, enable ? "enable" : "disable",
4161				usb3_lpm_names[state]);
4162		return 0;
4163	}
4164
4165	if (enable) {
4166		/*
4167		 * Now send the control transfer to enable device-initiated LPM
4168		 * for either U1 or U2.
4169		 */
4170		ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
4171				USB_REQ_SET_FEATURE,
4172				USB_RECIP_DEVICE,
4173				feature,
4174				0, NULL, 0,
4175				USB_CTRL_SET_TIMEOUT);
4176	} else {
4177		ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
4178				USB_REQ_CLEAR_FEATURE,
4179				USB_RECIP_DEVICE,
4180				feature,
4181				0, NULL, 0,
4182				USB_CTRL_SET_TIMEOUT);
4183	}
4184	if (ret < 0) {
4185		dev_warn(&udev->dev, "%s of device-initiated %s failed.\n",
4186				enable ? "Enable" : "Disable",
4187				usb3_lpm_names[state]);
4188		return -EBUSY;
4189	}
4190	return 0;
4191}
4192
4193static int usb_set_lpm_timeout(struct usb_device *udev,
4194		enum usb3_link_state state, int timeout)
4195{
4196	int ret;
4197	int feature;
4198
4199	switch (state) {
4200	case USB3_LPM_U1:
4201		feature = USB_PORT_FEAT_U1_TIMEOUT;
4202		break;
4203	case USB3_LPM_U2:
4204		feature = USB_PORT_FEAT_U2_TIMEOUT;
4205		break;
4206	default:
4207		dev_warn(&udev->dev, "%s: Can't set timeout for non-U1 or U2 state.\n",
4208				__func__);
4209		return -EINVAL;
4210	}
4211
4212	if (state == USB3_LPM_U1 && timeout > USB3_LPM_U1_MAX_TIMEOUT &&
4213			timeout != USB3_LPM_DEVICE_INITIATED) {
4214		dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x, "
4215				"which is a reserved value.\n",
4216				usb3_lpm_names[state], timeout);
4217		return -EINVAL;
4218	}
4219
4220	ret = set_port_feature(udev->parent,
4221			USB_PORT_LPM_TIMEOUT(timeout) | udev->portnum,
4222			feature);
4223	if (ret < 0) {
4224		dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x,"
4225				"error code %i\n", usb3_lpm_names[state],
4226				timeout, ret);
4227		return -EBUSY;
4228	}
4229	if (state == USB3_LPM_U1)
4230		udev->u1_params.timeout = timeout;
4231	else
4232		udev->u2_params.timeout = timeout;
4233	return 0;
4234}
4235
4236/*
4237 * Don't allow device intiated U1/U2 if the system exit latency + one bus
4238 * interval is greater than the minimum service interval of any active
4239 * periodic endpoint. See USB 3.2 section 9.4.9
4240 */
4241static bool usb_device_may_initiate_lpm(struct usb_device *udev,
4242					enum usb3_link_state state)
4243{
4244	unsigned int sel;		/* us */
4245	int i, j;
4246
4247	if (!udev->lpm_devinit_allow)
4248		return false;
4249
4250	if (state == USB3_LPM_U1)
4251		sel = DIV_ROUND_UP(udev->u1_params.sel, 1000);
4252	else if (state == USB3_LPM_U2)
4253		sel = DIV_ROUND_UP(udev->u2_params.sel, 1000);
4254	else
4255		return false;
4256
4257	for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
4258		struct usb_interface *intf;
4259		struct usb_endpoint_descriptor *desc;
4260		unsigned int interval;
4261
4262		intf = udev->actconfig->interface[i];
4263		if (!intf)
4264			continue;
4265
4266		for (j = 0; j < intf->cur_altsetting->desc.bNumEndpoints; j++) {
4267			desc = &intf->cur_altsetting->endpoint[j].desc;
4268
4269			if (usb_endpoint_xfer_int(desc) ||
4270			    usb_endpoint_xfer_isoc(desc)) {
4271				interval = (1 << (desc->bInterval - 1)) * 125;
4272				if (sel + 125 > interval)
4273					return false;
4274			}
4275		}
4276	}
4277	return true;
4278}
4279
4280/*
4281 * Enable the hub-initiated U1/U2 idle timeouts, and enable device-initiated
4282 * U1/U2 entry.
4283 *
4284 * We will attempt to enable U1 or U2, but there are no guarantees that the
4285 * control transfers to set the hub timeout or enable device-initiated U1/U2
4286 * will be successful.
4287 *
4288 * If the control transfer to enable device-initiated U1/U2 entry fails, then
4289 * hub-initiated U1/U2 will be disabled.
4290 *
4291 * If we cannot set the parent hub U1/U2 timeout, we attempt to let the xHCI
4292 * driver know about it.  If that call fails, it should be harmless, and just
4293 * take up more slightly more bus bandwidth for unnecessary U1/U2 exit latency.
4294 */
4295static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
4296		enum usb3_link_state state)
4297{
4298	int timeout;
4299	__u8 u1_mel;
4300	__le16 u2_mel;
4301
4302	/* Skip if the device BOS descriptor couldn't be read */
4303	if (!udev->bos)
4304		return;
4305
4306	u1_mel = udev->bos->ss_cap->bU1devExitLat;
4307	u2_mel = udev->bos->ss_cap->bU2DevExitLat;
4308
4309	/* If the device says it doesn't have *any* exit latency to come out of
4310	 * U1 or U2, it's probably lying.  Assume it doesn't implement that link
4311	 * state.
4312	 */
4313	if ((state == USB3_LPM_U1 && u1_mel == 0) ||
4314			(state == USB3_LPM_U2 && u2_mel == 0))
4315		return;
4316
 
 
 
 
 
 
 
 
 
 
 
4317	/* We allow the host controller to set the U1/U2 timeout internally
4318	 * first, so that it can change its schedule to account for the
4319	 * additional latency to send data to a device in a lower power
4320	 * link state.
4321	 */
4322	timeout = hcd->driver->enable_usb3_lpm_timeout(hcd, udev, state);
4323
4324	/* xHCI host controller doesn't want to enable this LPM state. */
4325	if (timeout == 0)
4326		return;
4327
4328	if (timeout < 0) {
4329		dev_warn(&udev->dev, "Could not enable %s link state, "
4330				"xHCI error %i.\n", usb3_lpm_names[state],
4331				timeout);
4332		return;
4333	}
4334
4335	if (usb_set_lpm_timeout(udev, state, timeout)) {
4336		/* If we can't set the parent hub U1/U2 timeout,
4337		 * device-initiated LPM won't be allowed either, so let the xHCI
4338		 * host know that this link state won't be enabled.
4339		 */
4340		hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
4341		return;
4342	}
4343
4344	/* Only a configured device will accept the Set Feature
4345	 * U1/U2_ENABLE
4346	 */
4347	if (udev->actconfig &&
4348	    usb_device_may_initiate_lpm(udev, state)) {
4349		if (usb_set_device_initiated_lpm(udev, state, true)) {
4350			/*
4351			 * Request to enable device initiated U1/U2 failed,
4352			 * better to turn off lpm in this case.
4353			 */
4354			usb_set_lpm_timeout(udev, state, 0);
4355			hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
4356			return;
4357		}
4358	}
4359
4360	if (state == USB3_LPM_U1)
4361		udev->usb3_lpm_u1_enabled = 1;
4362	else if (state == USB3_LPM_U2)
4363		udev->usb3_lpm_u2_enabled = 1;
4364}
4365/*
4366 * Disable the hub-initiated U1/U2 idle timeouts, and disable device-initiated
4367 * U1/U2 entry.
4368 *
4369 * If this function returns -EBUSY, the parent hub will still allow U1/U2 entry.
4370 * If zero is returned, the parent will not allow the link to go into U1/U2.
4371 *
4372 * If zero is returned, device-initiated U1/U2 entry may still be enabled, but
4373 * it won't have an effect on the bus link state because the parent hub will
4374 * still disallow device-initiated U1/U2 entry.
4375 *
4376 * If zero is returned, the xHCI host controller may still think U1/U2 entry is
4377 * possible.  The result will be slightly more bus bandwidth will be taken up
4378 * (to account for U1/U2 exit latency), but it should be harmless.
4379 */
4380static int usb_disable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
4381		enum usb3_link_state state)
4382{
4383	switch (state) {
4384	case USB3_LPM_U1:
4385	case USB3_LPM_U2:
4386		break;
4387	default:
4388		dev_warn(&udev->dev, "%s: Can't disable non-U1 or U2 state.\n",
4389				__func__);
4390		return -EINVAL;
4391	}
4392
4393	if (usb_set_lpm_timeout(udev, state, 0))
4394		return -EBUSY;
4395
4396	usb_set_device_initiated_lpm(udev, state, false);
4397
4398	if (hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state))
4399		dev_warn(&udev->dev, "Could not disable xHCI %s timeout, "
4400				"bus schedule bandwidth may be impacted.\n",
4401				usb3_lpm_names[state]);
4402
4403	/* As soon as usb_set_lpm_timeout(0) return 0, hub initiated LPM
4404	 * is disabled. Hub will disallows link to enter U1/U2 as well,
4405	 * even device is initiating LPM. Hence LPM is disabled if hub LPM
4406	 * timeout set to 0, no matter device-initiated LPM is disabled or
4407	 * not.
4408	 */
4409	if (state == USB3_LPM_U1)
4410		udev->usb3_lpm_u1_enabled = 0;
4411	else if (state == USB3_LPM_U2)
4412		udev->usb3_lpm_u2_enabled = 0;
4413
4414	return 0;
4415}
4416
4417/*
4418 * Disable hub-initiated and device-initiated U1 and U2 entry.
4419 * Caller must own the bandwidth_mutex.
4420 *
4421 * This will call usb_enable_lpm() on failure, which will decrement
4422 * lpm_disable_count, and will re-enable LPM if lpm_disable_count reaches zero.
4423 */
4424int usb_disable_lpm(struct usb_device *udev)
4425{
4426	struct usb_hcd *hcd;
4427
4428	if (!udev || !udev->parent ||
4429			udev->speed < USB_SPEED_SUPER ||
4430			!udev->lpm_capable ||
4431			udev->state < USB_STATE_CONFIGURED)
4432		return 0;
4433
4434	hcd = bus_to_hcd(udev->bus);
4435	if (!hcd || !hcd->driver->disable_usb3_lpm_timeout)
4436		return 0;
4437
4438	udev->lpm_disable_count++;
4439	if ((udev->u1_params.timeout == 0 && udev->u2_params.timeout == 0))
4440		return 0;
4441
4442	/* If LPM is enabled, attempt to disable it. */
4443	if (usb_disable_link_state(hcd, udev, USB3_LPM_U1))
4444		goto enable_lpm;
4445	if (usb_disable_link_state(hcd, udev, USB3_LPM_U2))
4446		goto enable_lpm;
4447
4448	return 0;
4449
4450enable_lpm:
4451	usb_enable_lpm(udev);
4452	return -EBUSY;
4453}
4454EXPORT_SYMBOL_GPL(usb_disable_lpm);
4455
4456/* Grab the bandwidth_mutex before calling usb_disable_lpm() */
4457int usb_unlocked_disable_lpm(struct usb_device *udev)
4458{
4459	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4460	int ret;
4461
4462	if (!hcd)
4463		return -EINVAL;
4464
4465	mutex_lock(hcd->bandwidth_mutex);
4466	ret = usb_disable_lpm(udev);
4467	mutex_unlock(hcd->bandwidth_mutex);
4468
4469	return ret;
4470}
4471EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
4472
4473/*
4474 * Attempt to enable device-initiated and hub-initiated U1 and U2 entry.  The
4475 * xHCI host policy may prevent U1 or U2 from being enabled.
4476 *
4477 * Other callers may have disabled link PM, so U1 and U2 entry will be disabled
4478 * until the lpm_disable_count drops to zero.  Caller must own the
4479 * bandwidth_mutex.
4480 */
4481void usb_enable_lpm(struct usb_device *udev)
4482{
4483	struct usb_hcd *hcd;
4484	struct usb_hub *hub;
4485	struct usb_port *port_dev;
4486
4487	if (!udev || !udev->parent ||
4488			udev->speed < USB_SPEED_SUPER ||
4489			!udev->lpm_capable ||
4490			udev->state < USB_STATE_CONFIGURED)
4491		return;
4492
4493	udev->lpm_disable_count--;
4494	hcd = bus_to_hcd(udev->bus);
4495	/* Double check that we can both enable and disable LPM.
4496	 * Device must be configured to accept set feature U1/U2 timeout.
4497	 */
4498	if (!hcd || !hcd->driver->enable_usb3_lpm_timeout ||
4499			!hcd->driver->disable_usb3_lpm_timeout)
4500		return;
4501
4502	if (udev->lpm_disable_count > 0)
4503		return;
4504
4505	hub = usb_hub_to_struct_hub(udev->parent);
4506	if (!hub)
4507		return;
4508
4509	port_dev = hub->ports[udev->portnum - 1];
4510
4511	if (port_dev->usb3_lpm_u1_permit)
4512		usb_enable_link_state(hcd, udev, USB3_LPM_U1);
4513
4514	if (port_dev->usb3_lpm_u2_permit)
4515		usb_enable_link_state(hcd, udev, USB3_LPM_U2);
4516}
4517EXPORT_SYMBOL_GPL(usb_enable_lpm);
4518
4519/* Grab the bandwidth_mutex before calling usb_enable_lpm() */
4520void usb_unlocked_enable_lpm(struct usb_device *udev)
4521{
4522	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4523
4524	if (!hcd)
4525		return;
4526
4527	mutex_lock(hcd->bandwidth_mutex);
4528	usb_enable_lpm(udev);
4529	mutex_unlock(hcd->bandwidth_mutex);
4530}
4531EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
4532
4533/* usb3 devices use U3 for disabled, make sure remote wakeup is disabled */
4534static void hub_usb3_port_prepare_disable(struct usb_hub *hub,
4535					  struct usb_port *port_dev)
4536{
4537	struct usb_device *udev = port_dev->child;
4538	int ret;
4539
4540	if (udev && udev->port_is_suspended && udev->do_remote_wakeup) {
4541		ret = hub_set_port_link_state(hub, port_dev->portnum,
4542					      USB_SS_PORT_LS_U0);
4543		if (!ret) {
4544			msleep(USB_RESUME_TIMEOUT);
4545			ret = usb_disable_remote_wakeup(udev);
4546		}
4547		if (ret)
4548			dev_warn(&udev->dev,
4549				 "Port disable: can't disable remote wake\n");
4550		udev->do_remote_wakeup = 0;
4551	}
4552}
4553
4554#else	/* CONFIG_PM */
4555
4556#define hub_suspend		NULL
4557#define hub_resume		NULL
4558#define hub_reset_resume	NULL
4559
4560static inline void hub_usb3_port_prepare_disable(struct usb_hub *hub,
4561						 struct usb_port *port_dev) { }
4562
4563int usb_disable_lpm(struct usb_device *udev)
4564{
4565	return 0;
4566}
4567EXPORT_SYMBOL_GPL(usb_disable_lpm);
4568
4569void usb_enable_lpm(struct usb_device *udev) { }
4570EXPORT_SYMBOL_GPL(usb_enable_lpm);
4571
4572int usb_unlocked_disable_lpm(struct usb_device *udev)
4573{
4574	return 0;
4575}
4576EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
4577
4578void usb_unlocked_enable_lpm(struct usb_device *udev) { }
4579EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
4580
4581int usb_disable_ltm(struct usb_device *udev)
4582{
4583	return 0;
4584}
4585EXPORT_SYMBOL_GPL(usb_disable_ltm);
4586
4587void usb_enable_ltm(struct usb_device *udev) { }
4588EXPORT_SYMBOL_GPL(usb_enable_ltm);
4589
4590static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
4591		u16 portstatus, u16 portchange)
4592{
4593	return 0;
4594}
4595
4596static int usb_req_set_sel(struct usb_device *udev)
4597{
4598	return 0;
4599}
4600
4601#endif	/* CONFIG_PM */
4602
4603/*
4604 * USB-3 does not have a similar link state as USB-2 that will avoid negotiating
4605 * a connection with a plugged-in cable but will signal the host when the cable
4606 * is unplugged. Disable remote wake and set link state to U3 for USB-3 devices
4607 */
4608static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
4609{
4610	struct usb_port *port_dev = hub->ports[port1 - 1];
4611	struct usb_device *hdev = hub->hdev;
4612	int ret = 0;
4613
4614	if (!hub->error) {
4615		if (hub_is_superspeed(hub->hdev)) {
4616			hub_usb3_port_prepare_disable(hub, port_dev);
4617			ret = hub_set_port_link_state(hub, port_dev->portnum,
4618						      USB_SS_PORT_LS_U3);
4619		} else {
4620			ret = usb_clear_port_feature(hdev, port1,
4621					USB_PORT_FEAT_ENABLE);
4622		}
4623	}
4624	if (port_dev->child && set_state)
4625		usb_set_device_state(port_dev->child, USB_STATE_NOTATTACHED);
4626	if (ret && ret != -ENODEV)
4627		dev_err(&port_dev->dev, "cannot disable (err = %d)\n", ret);
4628	return ret;
4629}
4630
4631/*
4632 * usb_port_disable - disable a usb device's upstream port
4633 * @udev: device to disable
4634 * Context: @udev locked, must be able to sleep.
4635 *
4636 * Disables a USB device that isn't in active use.
4637 */
4638int usb_port_disable(struct usb_device *udev)
4639{
4640	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
4641
4642	return hub_port_disable(hub, udev->portnum, 0);
4643}
4644
4645/* USB 2.0 spec, 7.1.7.3 / fig 7-29:
4646 *
4647 * Between connect detection and reset signaling there must be a delay
4648 * of 100ms at least for debounce and power-settling.  The corresponding
4649 * timer shall restart whenever the downstream port detects a disconnect.
4650 *
4651 * Apparently there are some bluetooth and irda-dongles and a number of
4652 * low-speed devices for which this debounce period may last over a second.
4653 * Not covered by the spec - but easy to deal with.
4654 *
4655 * This implementation uses a 1500ms total debounce timeout; if the
4656 * connection isn't stable by then it returns -ETIMEDOUT.  It checks
4657 * every 25ms for transient disconnects.  When the port status has been
4658 * unchanged for 100ms it returns the port status.
4659 */
4660int hub_port_debounce(struct usb_hub *hub, int port1, bool must_be_connected)
4661{
4662	int ret;
4663	u16 portchange, portstatus;
4664	unsigned connection = 0xffff;
4665	int total_time, stable_time = 0;
4666	struct usb_port *port_dev = hub->ports[port1 - 1];
4667
4668	for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
4669		ret = usb_hub_port_status(hub, port1, &portstatus, &portchange);
4670		if (ret < 0)
4671			return ret;
4672
4673		if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
4674		     (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
4675			if (!must_be_connected ||
4676			     (connection == USB_PORT_STAT_CONNECTION))
4677				stable_time += HUB_DEBOUNCE_STEP;
4678			if (stable_time >= HUB_DEBOUNCE_STABLE)
4679				break;
4680		} else {
4681			stable_time = 0;
4682			connection = portstatus & USB_PORT_STAT_CONNECTION;
4683		}
4684
4685		if (portchange & USB_PORT_STAT_C_CONNECTION) {
4686			usb_clear_port_feature(hub->hdev, port1,
4687					USB_PORT_FEAT_C_CONNECTION);
4688		}
4689
4690		if (total_time >= HUB_DEBOUNCE_TIMEOUT)
4691			break;
4692		msleep(HUB_DEBOUNCE_STEP);
4693	}
4694
4695	dev_dbg(&port_dev->dev, "debounce total %dms stable %dms status 0x%x\n",
4696			total_time, stable_time, portstatus);
4697
4698	if (stable_time < HUB_DEBOUNCE_STABLE)
4699		return -ETIMEDOUT;
4700	return portstatus;
4701}
4702
4703void usb_ep0_reinit(struct usb_device *udev)
4704{
4705	usb_disable_endpoint(udev, 0 + USB_DIR_IN, true);
4706	usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true);
4707	usb_enable_endpoint(udev, &udev->ep0, true);
4708}
4709EXPORT_SYMBOL_GPL(usb_ep0_reinit);
4710
4711#define usb_sndaddr0pipe()	(PIPE_CONTROL << 30)
 
4712
4713static int hub_set_address(struct usb_device *udev, int devnum)
4714{
4715	int retval;
4716	unsigned int timeout_ms = USB_CTRL_SET_TIMEOUT;
4717	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4718	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
4719
4720	if (hub->hdev->quirks & USB_QUIRK_SHORT_SET_ADDRESS_REQ_TIMEOUT)
4721		timeout_ms = USB_SHORT_SET_ADDRESS_REQ_TIMEOUT;
4722
4723	/*
4724	 * The host controller will choose the device address,
4725	 * instead of the core having chosen it earlier
4726	 */
4727	if (!hcd->driver->address_device && devnum <= 1)
4728		return -EINVAL;
4729	if (udev->state == USB_STATE_ADDRESS)
4730		return 0;
4731	if (udev->state != USB_STATE_DEFAULT)
4732		return -EINVAL;
4733	if (hcd->driver->address_device)
4734		retval = hcd->driver->address_device(hcd, udev, timeout_ms);
4735	else
4736		retval = usb_control_msg(udev, usb_sndaddr0pipe(),
4737				USB_REQ_SET_ADDRESS, 0, devnum, 0,
4738				NULL, 0, timeout_ms);
4739	if (retval == 0) {
4740		update_devnum(udev, devnum);
4741		/* Device now using proper address. */
4742		usb_set_device_state(udev, USB_STATE_ADDRESS);
4743		usb_ep0_reinit(udev);
4744	}
4745	return retval;
4746}
4747
4748/*
4749 * There are reports of USB 3.0 devices that say they support USB 2.0 Link PM
4750 * when they're plugged into a USB 2.0 port, but they don't work when LPM is
4751 * enabled.
4752 *
4753 * Only enable USB 2.0 Link PM if the port is internal (hardwired), or the
4754 * device says it supports the new USB 2.0 Link PM errata by setting the BESL
4755 * support bit in the BOS descriptor.
4756 */
4757static void hub_set_initial_usb2_lpm_policy(struct usb_device *udev)
4758{
4759	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
4760	int connect_type = USB_PORT_CONNECT_TYPE_UNKNOWN;
4761
4762	if (!udev->usb2_hw_lpm_capable || !udev->bos)
4763		return;
4764
4765	if (hub)
4766		connect_type = hub->ports[udev->portnum - 1]->connect_type;
4767
4768	if ((udev->bos->ext_cap->bmAttributes & cpu_to_le32(USB_BESL_SUPPORT)) ||
4769			connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
4770		udev->usb2_hw_lpm_allowed = 1;
4771		usb_enable_usb2_hardware_lpm(udev);
4772	}
4773}
4774
4775static int hub_enable_device(struct usb_device *udev)
4776{
4777	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4778
4779	if (!hcd->driver->enable_device)
4780		return 0;
4781	if (udev->state == USB_STATE_ADDRESS)
4782		return 0;
4783	if (udev->state != USB_STATE_DEFAULT)
4784		return -EINVAL;
4785
4786	return hcd->driver->enable_device(hcd, udev);
4787}
4788
4789/*
4790 * Get the bMaxPacketSize0 value during initialization by reading the
4791 * device's device descriptor.  Since we don't already know this value,
4792 * the transfer is unsafe and it ignores I/O errors, only testing for
4793 * reasonable received values.
4794 *
4795 * For "old scheme" initialization, size will be 8 so we read just the
4796 * start of the device descriptor, which should work okay regardless of
4797 * the actual bMaxPacketSize0 value.  For "new scheme" initialization,
4798 * size will be 64 (and buf will point to a sufficiently large buffer),
4799 * which might not be kosher according to the USB spec but it's what
4800 * Windows does and what many devices expect.
4801 *
4802 * Returns: bMaxPacketSize0 or a negative error code.
4803 */
4804static int get_bMaxPacketSize0(struct usb_device *udev,
4805		struct usb_device_descriptor *buf, int size, bool first_time)
4806{
4807	int i, rc;
4808
4809	/*
4810	 * Retry on all errors; some devices are flakey.
4811	 * 255 is for WUSB devices, we actually need to use
4812	 * 512 (WUSB1.0[4.8.1]).
4813	 */
4814	for (i = 0; i < GET_MAXPACKET0_TRIES; ++i) {
4815		/* Start with invalid values in case the transfer fails */
4816		buf->bDescriptorType = buf->bMaxPacketSize0 = 0;
4817		rc = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
4818				USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
4819				USB_DT_DEVICE << 8, 0,
4820				buf, size,
4821				initial_descriptor_timeout);
4822		switch (buf->bMaxPacketSize0) {
4823		case 8: case 16: case 32: case 64: case 9:
4824			if (buf->bDescriptorType == USB_DT_DEVICE) {
4825				rc = buf->bMaxPacketSize0;
4826				break;
4827			}
4828			fallthrough;
4829		default:
4830			if (rc >= 0)
4831				rc = -EPROTO;
4832			break;
4833		}
4834
4835		/*
4836		 * Some devices time out if they are powered on
4837		 * when already connected. They need a second
4838		 * reset, so return early. But only on the first
4839		 * attempt, lest we get into a time-out/reset loop.
4840		 */
4841		if (rc > 0 || (rc == -ETIMEDOUT && first_time &&
4842				udev->speed > USB_SPEED_FULL))
4843			break;
4844	}
4845	return rc;
4846}
4847
4848#define GET_DESCRIPTOR_BUFSIZE	64
4849
4850/* Reset device, (re)assign address, get device descriptor.
4851 * Device connection must be stable, no more debouncing needed.
4852 * Returns device in USB_STATE_ADDRESS, except on error.
4853 *
4854 * If this is called for an already-existing device (as part of
4855 * usb_reset_and_verify_device), the caller must own the device lock and
4856 * the port lock.  For a newly detected device that is not accessible
4857 * through any global pointers, it's not necessary to lock the device,
4858 * but it is still necessary to lock the port.
4859 *
4860 * For a newly detected device, @dev_descr must be NULL.  The device
4861 * descriptor retrieved from the device will then be stored in
4862 * @udev->descriptor.  For an already existing device, @dev_descr
4863 * must be non-NULL.  The device descriptor will be stored there,
4864 * not in @udev->descriptor, because descriptors for registered
4865 * devices are meant to be immutable.
4866 */
4867static int
4868hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1,
4869		int retry_counter, struct usb_device_descriptor *dev_descr)
4870{
4871	struct usb_device	*hdev = hub->hdev;
4872	struct usb_hcd		*hcd = bus_to_hcd(hdev->bus);
4873	struct usb_port		*port_dev = hub->ports[port1 - 1];
4874	int			retries, operations, retval, i;
4875	unsigned		delay = HUB_SHORT_RESET_TIME;
4876	enum usb_device_speed	oldspeed = udev->speed;
4877	const char		*speed;
4878	int			devnum = udev->devnum;
4879	const char		*driver_name;
4880	bool			do_new_scheme;
4881	const bool		initial = !dev_descr;
4882	int			maxp0;
4883	struct usb_device_descriptor	*buf, *descr;
4884
4885	buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
4886	if (!buf)
4887		return -ENOMEM;
4888
4889	/* root hub ports have a slightly longer reset period
4890	 * (from USB 2.0 spec, section 7.1.7.5)
4891	 */
4892	if (!hdev->parent) {
4893		delay = HUB_ROOT_RESET_TIME;
4894		if (port1 == hdev->bus->otg_port)
4895			hdev->bus->b_hnp_enable = 0;
4896	}
4897
4898	/* Some low speed devices have problems with the quick delay, so */
4899	/*  be a bit pessimistic with those devices. RHbug #23670 */
4900	if (oldspeed == USB_SPEED_LOW)
4901		delay = HUB_LONG_RESET_TIME;
4902
 
 
4903	/* Reset the device; full speed may morph to high speed */
4904	/* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */
4905	retval = hub_port_reset(hub, port1, udev, delay, false);
4906	if (retval < 0)		/* error or disconnect */
4907		goto fail;
4908	/* success, speed is known */
4909
4910	retval = -ENODEV;
4911
4912	/* Don't allow speed changes at reset, except usb 3.0 to faster */
4913	if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed &&
4914	    !(oldspeed == USB_SPEED_SUPER && udev->speed > oldspeed)) {
4915		dev_dbg(&udev->dev, "device reset changed speed!\n");
4916		goto fail;
4917	}
4918	oldspeed = udev->speed;
4919
4920	if (initial) {
4921		/* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
4922		 * it's fixed size except for full speed devices.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4923		 */
4924		switch (udev->speed) {
4925		case USB_SPEED_SUPER_PLUS:
4926		case USB_SPEED_SUPER:
4927			udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
4928			break;
4929		case USB_SPEED_HIGH:		/* fixed at 64 */
4930			udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
4931			break;
4932		case USB_SPEED_FULL:		/* 8, 16, 32, or 64 */
4933			/* to determine the ep0 maxpacket size, try to read
4934			 * the device descriptor to get bMaxPacketSize0 and
4935			 * then correct our initial guess.
4936			 */
4937			udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
4938			break;
4939		case USB_SPEED_LOW:		/* fixed at 8 */
4940			udev->ep0.desc.wMaxPacketSize = cpu_to_le16(8);
4941			break;
4942		default:
4943			goto fail;
4944		}
4945	}
4946
4947	speed = usb_speed_string(udev->speed);
 
 
 
4948
4949	/*
4950	 * The controller driver may be NULL if the controller device
4951	 * is the middle device between platform device and roothub.
4952	 * This middle device may not need a device driver due to
4953	 * all hardware control can be at platform device driver, this
4954	 * platform device is usually a dual-role USB controller device.
4955	 */
4956	if (udev->bus->controller->driver)
4957		driver_name = udev->bus->controller->driver->name;
4958	else
4959		driver_name = udev->bus->sysdev->driver->name;
4960
4961	if (udev->speed < USB_SPEED_SUPER)
4962		dev_info(&udev->dev,
4963				"%s %s USB device number %d using %s\n",
4964				(initial ? "new" : "reset"), speed,
4965				devnum, driver_name);
4966
4967	if (initial) {
4968		/* Set up TT records, if needed  */
4969		if (hdev->tt) {
4970			udev->tt = hdev->tt;
4971			udev->ttport = hdev->ttport;
4972		} else if (udev->speed != USB_SPEED_HIGH
4973				&& hdev->speed == USB_SPEED_HIGH) {
4974			if (!hub->tt.hub) {
4975				dev_err(&udev->dev, "parent hub has no TT\n");
4976				retval = -EINVAL;
4977				goto fail;
4978			}
4979			udev->tt = &hub->tt;
4980			udev->ttport = port1;
4981		}
 
 
4982	}
4983
4984	/* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
4985	 * Because device hardware and firmware is sometimes buggy in
4986	 * this area, and this is how Linux has done it for ages.
4987	 * Change it cautiously.
4988	 *
4989	 * NOTE:  If use_new_scheme() is true we will start by issuing
4990	 * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
4991	 * so it may help with some non-standards-compliant devices.
4992	 * Otherwise we start with SET_ADDRESS and then try to read the
4993	 * first 8 bytes of the device descriptor to get the ep0 maxpacket
4994	 * value.
4995	 */
4996	do_new_scheme = use_new_scheme(udev, retry_counter, port_dev);
4997
4998	for (retries = 0; retries < GET_DESCRIPTOR_TRIES; (++retries, msleep(100))) {
4999		if (hub_port_stop_enumerate(hub, port1, retries)) {
5000			retval = -ENODEV;
5001			break;
5002		}
5003
5004		if (do_new_scheme) {
 
 
 
5005			retval = hub_enable_device(udev);
5006			if (retval < 0) {
5007				dev_err(&udev->dev,
5008					"hub failed to enable device, error %d\n",
5009					retval);
5010				goto fail;
5011			}
5012
5013			maxp0 = get_bMaxPacketSize0(udev, buf,
5014					GET_DESCRIPTOR_BUFSIZE, retries == 0);
5015			if (maxp0 > 0 && !initial &&
5016					maxp0 != udev->descriptor.bMaxPacketSize0) {
5017				dev_err(&udev->dev, "device reset changed ep0 maxpacket size!\n");
5018				retval = -ENODEV;
5019				goto fail;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5020			}
 
 
 
5021
5022			retval = hub_port_reset(hub, port1, udev, delay, false);
5023			if (retval < 0)		/* error or disconnect */
5024				goto fail;
5025			if (oldspeed != udev->speed) {
5026				dev_dbg(&udev->dev,
5027					"device reset changed speed!\n");
5028				retval = -ENODEV;
5029				goto fail;
5030			}
5031			if (maxp0 < 0) {
5032				if (maxp0 != -ENODEV)
5033					dev_err(&udev->dev, "device descriptor read/64, error %d\n",
5034							maxp0);
5035				retval = maxp0;
5036				continue;
5037			}
5038		}
5039
5040		for (operations = 0; operations < SET_ADDRESS_TRIES; ++operations) {
5041			retval = hub_set_address(udev, devnum);
5042			if (retval >= 0)
5043				break;
5044			msleep(200);
5045		}
5046		if (retval < 0) {
5047			if (retval != -ENODEV)
5048				dev_err(&udev->dev, "device not accepting address %d, error %d\n",
5049						devnum, retval);
5050			goto fail;
5051		}
5052		if (udev->speed >= USB_SPEED_SUPER) {
5053			devnum = udev->devnum;
5054			dev_info(&udev->dev,
5055					"%s SuperSpeed%s%s USB device number %d using %s\n",
5056					(udev->config) ? "reset" : "new",
5057				 (udev->speed == USB_SPEED_SUPER_PLUS) ?
5058						" Plus" : "",
5059				 (udev->ssp_rate == USB_SSP_GEN_2x2) ?
5060						" Gen 2x2" :
5061				 (udev->ssp_rate == USB_SSP_GEN_2x1) ?
5062						" Gen 2x1" :
5063				 (udev->ssp_rate == USB_SSP_GEN_1x2) ?
5064						" Gen 1x2" : "",
5065				 devnum, driver_name);
5066		}
5067
5068		/*
5069		 * cope with hardware quirkiness:
5070		 *  - let SET_ADDRESS settle, some device hardware wants it
5071		 *  - read ep0 maxpacket even for high and low speed,
5072		 */
5073		msleep(10);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5074
5075		if (do_new_scheme)
5076			break;
 
 
 
 
 
 
5077
5078		maxp0 = get_bMaxPacketSize0(udev, buf, 8, retries == 0);
5079		if (maxp0 < 0) {
5080			retval = maxp0;
5081			if (retval != -ENODEV)
5082				dev_err(&udev->dev,
5083					"device descriptor read/8, error %d\n",
5084					retval);
 
 
5085		} else {
5086			u32 delay;
5087
5088			if (!initial && maxp0 != udev->descriptor.bMaxPacketSize0) {
5089				dev_err(&udev->dev, "device reset changed ep0 maxpacket size!\n");
5090				retval = -ENODEV;
5091				goto fail;
5092			}
5093
5094			delay = udev->parent->hub_delay;
5095			udev->hub_delay = min_t(u32, delay,
5096						USB_TP_TRANSMISSION_DELAY_MAX);
5097			retval = usb_set_isoch_delay(udev);
5098			if (retval) {
5099				dev_dbg(&udev->dev,
5100					"Failed set isoch delay, error %d\n",
5101					retval);
5102				retval = 0;
5103			}
5104			break;
5105		}
5106	}
5107	if (retval)
5108		goto fail;
5109
5110	/*
5111	 * Check the ep0 maxpacket guess and correct it if necessary.
5112	 * maxp0 is the value stored in the device descriptor;
5113	 * i is the value it encodes (logarithmic for SuperSpeed or greater).
5114	 */
5115	i = maxp0;
5116	if (udev->speed >= USB_SPEED_SUPER) {
5117		if (maxp0 <= 16)
5118			i = 1 << maxp0;
5119		else
5120			i = 0;		/* Invalid */
 
 
 
5121	}
5122	if (usb_endpoint_maxp(&udev->ep0.desc) == i) {
5123		;	/* Initial ep0 maxpacket guess is right */
5124	} else if (((udev->speed == USB_SPEED_FULL ||
5125				udev->speed == USB_SPEED_HIGH) &&
5126			(i == 8 || i == 16 || i == 32 || i == 64)) ||
5127			(udev->speed >= USB_SPEED_SUPER && i > 0)) {
5128		/* Initial guess is wrong; use the descriptor's value */
 
 
 
 
 
 
5129		if (udev->speed == USB_SPEED_FULL)
5130			dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
5131		else
5132			dev_warn(&udev->dev, "Using ep0 maxpacket: %d\n", i);
5133		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
5134		usb_ep0_reinit(udev);
5135	} else {
5136		/* Initial guess is wrong and descriptor's value is invalid */
5137		dev_err(&udev->dev, "Invalid ep0 maxpacket: %d\n", maxp0);
5138		retval = -EMSGSIZE;
5139		goto fail;
5140	}
5141
5142	descr = usb_get_device_descriptor(udev);
5143	if (IS_ERR(descr)) {
5144		retval = PTR_ERR(descr);
5145		if (retval != -ENODEV)
5146			dev_err(&udev->dev, "device descriptor read/all, error %d\n",
5147					retval);
5148		goto fail;
5149	}
5150	if (initial)
5151		udev->descriptor = *descr;
5152	else
5153		*dev_descr = *descr;
5154	kfree(descr);
5155
5156	/*
5157	 * Some superspeed devices have finished the link training process
5158	 * and attached to a superspeed hub port, but the device descriptor
5159	 * got from those devices show they aren't superspeed devices. Warm
5160	 * reset the port attached by the devices can fix them.
5161	 */
5162	if ((udev->speed >= USB_SPEED_SUPER) &&
5163			(le16_to_cpu(udev->descriptor.bcdUSB) < 0x0300)) {
5164		dev_err(&udev->dev, "got a wrong device descriptor, warm reset device\n");
5165		hub_port_reset(hub, port1, udev, HUB_BH_RESET_TIME, true);
5166		retval = -EINVAL;
5167		goto fail;
5168	}
5169
5170	usb_detect_quirks(udev);
5171
5172	if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0201) {
5173		retval = usb_get_bos_descriptor(udev);
5174		if (!retval) {
5175			udev->lpm_capable = usb_device_supports_lpm(udev);
5176			udev->lpm_disable_count = 1;
5177			usb_set_lpm_parameters(udev);
5178			usb_req_set_sel(udev);
5179		}
5180	}
5181
5182	retval = 0;
5183	/* notify HCD that we have a device connected and addressed */
5184	if (hcd->driver->update_device)
5185		hcd->driver->update_device(hcd, udev);
5186	hub_set_initial_usb2_lpm_policy(udev);
5187fail:
5188	if (retval) {
5189		hub_port_disable(hub, port1, 0);
5190		update_devnum(udev, devnum);	/* for disconnect processing */
5191	}
5192	kfree(buf);
5193	return retval;
5194}
5195
5196static void
5197check_highspeed(struct usb_hub *hub, struct usb_device *udev, int port1)
5198{
5199	struct usb_qualifier_descriptor	*qual;
5200	int				status;
5201
5202	if (udev->quirks & USB_QUIRK_DEVICE_QUALIFIER)
5203		return;
5204
5205	qual = kmalloc(sizeof *qual, GFP_KERNEL);
5206	if (qual == NULL)
5207		return;
5208
5209	status = usb_get_descriptor(udev, USB_DT_DEVICE_QUALIFIER, 0,
5210			qual, sizeof *qual);
5211	if (status == sizeof *qual) {
5212		dev_info(&udev->dev, "not running at top speed; "
5213			"connect to a high speed hub\n");
5214		/* hub LEDs are probably harder to miss than syslog */
5215		if (hub->has_indicators) {
5216			hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
5217			queue_delayed_work(system_power_efficient_wq,
5218					&hub->leds, 0);
5219		}
5220	}
5221	kfree(qual);
5222}
5223
5224static unsigned
5225hub_power_remaining(struct usb_hub *hub)
5226{
5227	struct usb_device *hdev = hub->hdev;
5228	int remaining;
5229	int port1;
5230
5231	if (!hub->limited_power)
5232		return 0;
5233
5234	remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
5235	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
5236		struct usb_port *port_dev = hub->ports[port1 - 1];
5237		struct usb_device *udev = port_dev->child;
5238		unsigned unit_load;
5239		int delta;
5240
5241		if (!udev)
5242			continue;
5243		if (hub_is_superspeed(udev))
5244			unit_load = 150;
5245		else
5246			unit_load = 100;
5247
5248		/*
5249		 * Unconfigured devices may not use more than one unit load,
5250		 * or 8mA for OTG ports
5251		 */
5252		if (udev->actconfig)
5253			delta = usb_get_max_power(udev, udev->actconfig);
5254		else if (port1 != udev->bus->otg_port || hdev->parent)
5255			delta = unit_load;
5256		else
5257			delta = 8;
5258		if (delta > hub->mA_per_port)
5259			dev_warn(&port_dev->dev, "%dmA is over %umA budget!\n",
5260					delta, hub->mA_per_port);
5261		remaining -= delta;
5262	}
5263	if (remaining < 0) {
5264		dev_warn(hub->intfdev, "%dmA over power budget!\n",
5265			-remaining);
5266		remaining = 0;
5267	}
5268	return remaining;
5269}
5270
5271
5272static int descriptors_changed(struct usb_device *udev,
5273		struct usb_device_descriptor *new_device_descriptor,
5274		struct usb_host_bos *old_bos)
5275{
5276	int		changed = 0;
5277	unsigned	index;
5278	unsigned	serial_len = 0;
5279	unsigned	len;
5280	unsigned	old_length;
5281	int		length;
5282	char		*buf;
5283
5284	if (memcmp(&udev->descriptor, new_device_descriptor,
5285			sizeof(*new_device_descriptor)) != 0)
5286		return 1;
5287
5288	if ((old_bos && !udev->bos) || (!old_bos && udev->bos))
5289		return 1;
5290	if (udev->bos) {
5291		len = le16_to_cpu(udev->bos->desc->wTotalLength);
5292		if (len != le16_to_cpu(old_bos->desc->wTotalLength))
5293			return 1;
5294		if (memcmp(udev->bos->desc, old_bos->desc, len))
5295			return 1;
5296	}
5297
5298	/* Since the idVendor, idProduct, and bcdDevice values in the
5299	 * device descriptor haven't changed, we will assume the
5300	 * Manufacturer and Product strings haven't changed either.
5301	 * But the SerialNumber string could be different (e.g., a
5302	 * different flash card of the same brand).
5303	 */
5304	if (udev->serial)
5305		serial_len = strlen(udev->serial) + 1;
5306
5307	len = serial_len;
5308	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
5309		old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
5310		len = max(len, old_length);
5311	}
5312
5313	buf = kmalloc(len, GFP_NOIO);
5314	if (!buf)
5315		/* assume the worst */
5316		return 1;
5317
5318	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
5319		old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
5320		length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
5321				old_length);
5322		if (length != old_length) {
5323			dev_dbg(&udev->dev, "config index %d, error %d\n",
5324					index, length);
5325			changed = 1;
5326			break;
5327		}
5328		if (memcmp(buf, udev->rawdescriptors[index], old_length)
5329				!= 0) {
5330			dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
5331				index,
5332				((struct usb_config_descriptor *) buf)->
5333					bConfigurationValue);
5334			changed = 1;
5335			break;
5336		}
5337	}
5338
5339	if (!changed && serial_len) {
5340		length = usb_string(udev, udev->descriptor.iSerialNumber,
5341				buf, serial_len);
5342		if (length + 1 != serial_len) {
5343			dev_dbg(&udev->dev, "serial string error %d\n",
5344					length);
5345			changed = 1;
5346		} else if (memcmp(buf, udev->serial, length) != 0) {
5347			dev_dbg(&udev->dev, "serial string changed\n");
5348			changed = 1;
5349		}
5350	}
5351
5352	kfree(buf);
5353	return changed;
5354}
5355
5356static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
5357		u16 portchange)
5358{
5359	int status = -ENODEV;
5360	int i;
5361	unsigned unit_load;
5362	struct usb_device *hdev = hub->hdev;
5363	struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
5364	struct usb_port *port_dev = hub->ports[port1 - 1];
5365	struct usb_device *udev = port_dev->child;
5366	static int unreliable_port = -1;
5367	bool retry_locked;
5368
5369	/* Disconnect any existing devices under this port */
5370	if (udev) {
5371		if (hcd->usb_phy && !hdev->parent)
5372			usb_phy_notify_disconnect(hcd->usb_phy, udev->speed);
5373		usb_disconnect(&port_dev->child);
5374	}
5375
5376	/* We can forget about a "removed" device when there's a physical
5377	 * disconnect or the connect status changes.
5378	 */
5379	if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
5380			(portchange & USB_PORT_STAT_C_CONNECTION))
5381		clear_bit(port1, hub->removed_bits);
5382
5383	if (portchange & (USB_PORT_STAT_C_CONNECTION |
5384				USB_PORT_STAT_C_ENABLE)) {
5385		status = hub_port_debounce_be_stable(hub, port1);
5386		if (status < 0) {
5387			if (status != -ENODEV &&
5388				port1 != unreliable_port &&
5389				printk_ratelimit())
5390				dev_err(&port_dev->dev, "connect-debounce failed\n");
5391			portstatus &= ~USB_PORT_STAT_CONNECTION;
5392			unreliable_port = port1;
5393		} else {
5394			portstatus = status;
5395		}
5396	}
5397
5398	/* Return now if debouncing failed or nothing is connected or
5399	 * the device was "removed".
5400	 */
5401	if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
5402			test_bit(port1, hub->removed_bits)) {
5403
5404		/*
5405		 * maybe switch power back on (e.g. root hub was reset)
5406		 * but only if the port isn't owned by someone else.
5407		 */
5408		if (hub_is_port_power_switchable(hub)
5409				&& !usb_port_is_power_on(hub, portstatus)
5410				&& !port_dev->port_owner)
5411			set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
5412
5413		if (portstatus & USB_PORT_STAT_ENABLE)
5414			goto done;
5415		return;
5416	}
5417	if (hub_is_superspeed(hub->hdev))
5418		unit_load = 150;
5419	else
5420		unit_load = 100;
5421
5422	status = 0;
5423
5424	for (i = 0; i < PORT_INIT_TRIES; i++) {
5425		if (hub_port_stop_enumerate(hub, port1, i)) {
5426			status = -ENODEV;
5427			break;
5428		}
5429
5430		usb_lock_port(port_dev);
5431		mutex_lock(hcd->address0_mutex);
5432		retry_locked = true;
5433		/* reallocate for each attempt, since references
5434		 * to the previous one can escape in various ways
5435		 */
5436		udev = usb_alloc_dev(hdev, hdev->bus, port1);
5437		if (!udev) {
5438			dev_err(&port_dev->dev,
5439					"couldn't allocate usb_device\n");
5440			mutex_unlock(hcd->address0_mutex);
5441			usb_unlock_port(port_dev);
5442			goto done;
5443		}
5444
5445		usb_set_device_state(udev, USB_STATE_POWERED);
5446		udev->bus_mA = hub->mA_per_port;
5447		udev->level = hdev->level + 1;
 
5448
5449		/* Devices connected to SuperSpeed hubs are USB 3.0 or later */
5450		if (hub_is_superspeed(hub->hdev))
5451			udev->speed = USB_SPEED_SUPER;
5452		else
5453			udev->speed = USB_SPEED_UNKNOWN;
5454
5455		choose_devnum(udev);
5456		if (udev->devnum <= 0) {
5457			status = -ENOTCONN;	/* Don't retry */
5458			goto loop;
5459		}
5460
5461		/* reset (non-USB 3.0 devices) and get descriptor */
5462		status = hub_port_init(hub, udev, port1, i, NULL);
 
 
5463		if (status < 0)
5464			goto loop;
5465
5466		mutex_unlock(hcd->address0_mutex);
5467		usb_unlock_port(port_dev);
5468		retry_locked = false;
5469
5470		if (udev->quirks & USB_QUIRK_DELAY_INIT)
5471			msleep(2000);
5472
5473		/* consecutive bus-powered hubs aren't reliable; they can
5474		 * violate the voltage drop budget.  if the new child has
5475		 * a "powered" LED, users should notice we didn't enable it
5476		 * (without reading syslog), even without per-port LEDs
5477		 * on the parent.
5478		 */
5479		if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
5480				&& udev->bus_mA <= unit_load) {
5481			u16	devstat;
5482
5483			status = usb_get_std_status(udev, USB_RECIP_DEVICE, 0,
5484					&devstat);
5485			if (status) {
5486				dev_dbg(&udev->dev, "get status %d ?\n", status);
5487				goto loop_disable;
5488			}
5489			if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
5490				dev_err(&udev->dev,
5491					"can't connect bus-powered hub "
5492					"to this port\n");
5493				if (hub->has_indicators) {
5494					hub->indicator[port1-1] =
5495						INDICATOR_AMBER_BLINK;
5496					queue_delayed_work(
5497						system_power_efficient_wq,
5498						&hub->leds, 0);
5499				}
5500				status = -ENOTCONN;	/* Don't retry */
5501				goto loop_disable;
5502			}
5503		}
5504
5505		/* check for devices running slower than they could */
5506		if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
5507				&& udev->speed == USB_SPEED_FULL
5508				&& highspeed_hubs != 0)
5509			check_highspeed(hub, udev, port1);
5510
5511		/* Store the parent's children[] pointer.  At this point
5512		 * udev becomes globally accessible, although presumably
5513		 * no one will look at it until hdev is unlocked.
5514		 */
5515		status = 0;
5516
5517		mutex_lock(&usb_port_peer_mutex);
5518
5519		/* We mustn't add new devices if the parent hub has
5520		 * been disconnected; we would race with the
5521		 * recursively_mark_NOTATTACHED() routine.
5522		 */
5523		spin_lock_irq(&device_state_lock);
5524		if (hdev->state == USB_STATE_NOTATTACHED)
5525			status = -ENOTCONN;
5526		else
5527			port_dev->child = udev;
5528		spin_unlock_irq(&device_state_lock);
5529		mutex_unlock(&usb_port_peer_mutex);
5530
5531		/* Run it through the hoops (find a driver, etc) */
5532		if (!status) {
5533			status = usb_new_device(udev);
5534			if (status) {
5535				mutex_lock(&usb_port_peer_mutex);
5536				spin_lock_irq(&device_state_lock);
5537				port_dev->child = NULL;
5538				spin_unlock_irq(&device_state_lock);
5539				mutex_unlock(&usb_port_peer_mutex);
5540			} else {
5541				if (hcd->usb_phy && !hdev->parent)
5542					usb_phy_notify_connect(hcd->usb_phy,
5543							udev->speed);
5544			}
5545		}
5546
5547		if (status)
5548			goto loop_disable;
5549
5550		status = hub_power_remaining(hub);
5551		if (status)
5552			dev_dbg(hub->intfdev, "%dmA power budget left\n", status);
5553
5554		return;
5555
5556loop_disable:
5557		hub_port_disable(hub, port1, 1);
5558loop:
5559		usb_ep0_reinit(udev);
5560		release_devnum(udev);
5561		hub_free_dev(udev);
5562		if (retry_locked) {
5563			mutex_unlock(hcd->address0_mutex);
5564			usb_unlock_port(port_dev);
5565		}
5566		usb_put_dev(udev);
5567		if ((status == -ENOTCONN) || (status == -ENOTSUPP))
5568			break;
5569
5570		/* When halfway through our retry count, power-cycle the port */
5571		if (i == (PORT_INIT_TRIES - 1) / 2) {
5572			dev_info(&port_dev->dev, "attempt power cycle\n");
5573			usb_hub_set_port_power(hdev, hub, port1, false);
5574			msleep(2 * hub_power_on_good_delay(hub));
5575			usb_hub_set_port_power(hdev, hub, port1, true);
5576			msleep(hub_power_on_good_delay(hub));
5577		}
5578	}
5579	if (hub->hdev->parent ||
5580			!hcd->driver->port_handed_over ||
5581			!(hcd->driver->port_handed_over)(hcd, port1)) {
5582		if (status != -ENOTCONN && status != -ENODEV)
5583			dev_err(&port_dev->dev,
5584					"unable to enumerate USB device\n");
5585	}
5586
5587done:
5588	hub_port_disable(hub, port1, 1);
5589	if (hcd->driver->relinquish_port && !hub->hdev->parent) {
5590		if (status != -ENOTCONN && status != -ENODEV)
5591			hcd->driver->relinquish_port(hcd, port1);
5592	}
5593}
5594
5595/* Handle physical or logical connection change events.
5596 * This routine is called when:
5597 *	a port connection-change occurs;
5598 *	a port enable-change occurs (often caused by EMI);
5599 *	usb_reset_and_verify_device() encounters changed descriptors (as from
5600 *		a firmware download)
5601 * caller already locked the hub
5602 */
5603static void hub_port_connect_change(struct usb_hub *hub, int port1,
5604					u16 portstatus, u16 portchange)
5605		__must_hold(&port_dev->status_lock)
5606{
5607	struct usb_port *port_dev = hub->ports[port1 - 1];
5608	struct usb_device *udev = port_dev->child;
5609	struct usb_device_descriptor *descr;
5610	int status = -ENODEV;
 
5611
5612	dev_dbg(&port_dev->dev, "status %04x, change %04x, %s\n", portstatus,
5613			portchange, portspeed(hub, portstatus));
5614
5615	if (hub->has_indicators) {
5616		set_port_led(hub, port1, HUB_LED_AUTO);
5617		hub->indicator[port1-1] = INDICATOR_AUTO;
5618	}
5619
5620#ifdef	CONFIG_USB_OTG
5621	/* during HNP, don't repeat the debounce */
5622	if (hub->hdev->bus->is_b_host)
5623		portchange &= ~(USB_PORT_STAT_C_CONNECTION |
5624				USB_PORT_STAT_C_ENABLE);
5625#endif
5626
5627	/* Try to resuscitate an existing device */
5628	if ((portstatus & USB_PORT_STAT_CONNECTION) && udev &&
5629			udev->state != USB_STATE_NOTATTACHED) {
5630		if (portstatus & USB_PORT_STAT_ENABLE) {
5631			/*
5632			 * USB-3 connections are initialized automatically by
5633			 * the hostcontroller hardware. Therefore check for
5634			 * changed device descriptors before resuscitating the
5635			 * device.
5636			 */
5637			descr = usb_get_device_descriptor(udev);
5638			if (IS_ERR(descr)) {
 
 
5639				dev_dbg(&udev->dev,
5640						"can't read device descriptor %ld\n",
5641						PTR_ERR(descr));
5642			} else {
5643				if (descriptors_changed(udev, descr,
5644						udev->bos)) {
5645					dev_dbg(&udev->dev,
5646							"device descriptor has changed\n");
 
 
5647				} else {
5648					status = 0; /* Nothing to do */
5649				}
5650				kfree(descr);
5651			}
5652#ifdef CONFIG_PM
5653		} else if (udev->state == USB_STATE_SUSPENDED &&
5654				udev->persist_enabled) {
5655			/* For a suspended device, treat this as a
5656			 * remote wakeup event.
5657			 */
5658			usb_unlock_port(port_dev);
5659			status = usb_remote_wakeup(udev);
5660			usb_lock_port(port_dev);
5661#endif
5662		} else {
5663			/* Don't resuscitate */;
5664		}
5665	}
5666	clear_bit(port1, hub->change_bits);
5667
5668	/* successfully revalidated the connection */
5669	if (status == 0)
5670		return;
5671
5672	usb_unlock_port(port_dev);
5673	hub_port_connect(hub, port1, portstatus, portchange);
5674	usb_lock_port(port_dev);
5675}
5676
5677/* Handle notifying userspace about hub over-current events */
5678static void port_over_current_notify(struct usb_port *port_dev)
5679{
5680	char *envp[3] = { NULL, NULL, NULL };
5681	struct device *hub_dev;
5682	char *port_dev_path;
5683
5684	sysfs_notify(&port_dev->dev.kobj, NULL, "over_current_count");
5685
5686	hub_dev = port_dev->dev.parent;
5687
5688	if (!hub_dev)
5689		return;
5690
5691	port_dev_path = kobject_get_path(&port_dev->dev.kobj, GFP_KERNEL);
5692	if (!port_dev_path)
5693		return;
5694
5695	envp[0] = kasprintf(GFP_KERNEL, "OVER_CURRENT_PORT=%s", port_dev_path);
5696	if (!envp[0])
5697		goto exit;
5698
5699	envp[1] = kasprintf(GFP_KERNEL, "OVER_CURRENT_COUNT=%u",
5700			port_dev->over_current_count);
5701	if (!envp[1])
5702		goto exit;
5703
 
5704	kobject_uevent_env(&hub_dev->kobj, KOBJ_CHANGE, envp);
5705
5706exit:
5707	kfree(envp[1]);
 
5708	kfree(envp[0]);
 
5709	kfree(port_dev_path);
5710}
5711
5712static void port_event(struct usb_hub *hub, int port1)
5713		__must_hold(&port_dev->status_lock)
5714{
5715	int connect_change;
5716	struct usb_port *port_dev = hub->ports[port1 - 1];
5717	struct usb_device *udev = port_dev->child;
5718	struct usb_device *hdev = hub->hdev;
5719	u16 portstatus, portchange;
5720	int i = 0;
5721
5722	connect_change = test_bit(port1, hub->change_bits);
5723	clear_bit(port1, hub->event_bits);
5724	clear_bit(port1, hub->wakeup_bits);
5725
5726	if (usb_hub_port_status(hub, port1, &portstatus, &portchange) < 0)
5727		return;
5728
5729	if (portchange & USB_PORT_STAT_C_CONNECTION) {
5730		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
5731		connect_change = 1;
5732	}
5733
5734	if (portchange & USB_PORT_STAT_C_ENABLE) {
5735		if (!connect_change)
5736			dev_dbg(&port_dev->dev, "enable change, status %08x\n",
5737					portstatus);
5738		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
5739
5740		/*
5741		 * EM interference sometimes causes badly shielded USB devices
5742		 * to be shutdown by the hub, this hack enables them again.
5743		 * Works at least with mouse driver.
5744		 */
5745		if (!(portstatus & USB_PORT_STAT_ENABLE)
5746		    && !connect_change && udev) {
5747			dev_err(&port_dev->dev, "disabled by hub (EMI?), re-enabling...\n");
5748			connect_change = 1;
5749		}
5750	}
5751
5752	if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
5753		u16 status = 0, unused;
5754		port_dev->over_current_count++;
5755		port_over_current_notify(port_dev);
5756
5757		dev_dbg(&port_dev->dev, "over-current change #%u\n",
5758			port_dev->over_current_count);
5759		usb_clear_port_feature(hdev, port1,
5760				USB_PORT_FEAT_C_OVER_CURRENT);
5761		msleep(100);	/* Cool down */
5762		hub_power_on(hub, true);
5763		usb_hub_port_status(hub, port1, &status, &unused);
5764		if (status & USB_PORT_STAT_OVERCURRENT)
5765			dev_err(&port_dev->dev, "over-current condition\n");
5766	}
5767
5768	if (portchange & USB_PORT_STAT_C_RESET) {
5769		dev_dbg(&port_dev->dev, "reset change\n");
5770		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_RESET);
5771	}
5772	if ((portchange & USB_PORT_STAT_C_BH_RESET)
5773	    && hub_is_superspeed(hdev)) {
5774		dev_dbg(&port_dev->dev, "warm reset change\n");
5775		usb_clear_port_feature(hdev, port1,
5776				USB_PORT_FEAT_C_BH_PORT_RESET);
5777	}
5778	if (portchange & USB_PORT_STAT_C_LINK_STATE) {
5779		dev_dbg(&port_dev->dev, "link state change\n");
5780		usb_clear_port_feature(hdev, port1,
5781				USB_PORT_FEAT_C_PORT_LINK_STATE);
5782	}
5783	if (portchange & USB_PORT_STAT_C_CONFIG_ERROR) {
5784		dev_warn(&port_dev->dev, "config error\n");
5785		usb_clear_port_feature(hdev, port1,
5786				USB_PORT_FEAT_C_PORT_CONFIG_ERROR);
5787	}
5788
5789	/* skip port actions that require the port to be powered on */
5790	if (!pm_runtime_active(&port_dev->dev))
5791		return;
5792
5793	/* skip port actions if ignore_event and early_stop are true */
5794	if (port_dev->ignore_event && port_dev->early_stop)
5795		return;
5796
5797	if (hub_handle_remote_wakeup(hub, port1, portstatus, portchange))
5798		connect_change = 1;
5799
5800	/*
5801	 * Avoid trying to recover a USB3 SS.Inactive port with a warm reset if
5802	 * the device was disconnected. A 12ms disconnect detect timer in
5803	 * SS.Inactive state transitions the port to RxDetect automatically.
5804	 * SS.Inactive link error state is common during device disconnect.
5805	 */
5806	while (hub_port_warm_reset_required(hub, port1, portstatus)) {
5807		if ((i++ < DETECT_DISCONNECT_TRIES) && udev) {
5808			u16 unused;
5809
5810			msleep(20);
5811			usb_hub_port_status(hub, port1, &portstatus, &unused);
5812			dev_dbg(&port_dev->dev, "Wait for inactive link disconnect detect\n");
5813			continue;
5814		} else if (!udev || !(portstatus & USB_PORT_STAT_CONNECTION)
5815				|| udev->state == USB_STATE_NOTATTACHED) {
5816			dev_dbg(&port_dev->dev, "do warm reset, port only\n");
5817			if (hub_port_reset(hub, port1, NULL,
5818					HUB_BH_RESET_TIME, true) < 0)
5819				hub_port_disable(hub, port1, 1);
5820		} else {
5821			dev_dbg(&port_dev->dev, "do warm reset, full device\n");
5822			usb_unlock_port(port_dev);
5823			usb_lock_device(udev);
5824			usb_reset_device(udev);
5825			usb_unlock_device(udev);
5826			usb_lock_port(port_dev);
5827			connect_change = 0;
5828		}
5829		break;
5830	}
5831
5832	if (connect_change)
5833		hub_port_connect_change(hub, port1, portstatus, portchange);
5834}
5835
5836static void hub_event(struct work_struct *work)
5837{
5838	struct usb_device *hdev;
5839	struct usb_interface *intf;
5840	struct usb_hub *hub;
5841	struct device *hub_dev;
5842	u16 hubstatus;
5843	u16 hubchange;
5844	int i, ret;
5845
5846	hub = container_of(work, struct usb_hub, events);
5847	hdev = hub->hdev;
5848	hub_dev = hub->intfdev;
5849	intf = to_usb_interface(hub_dev);
5850
5851	kcov_remote_start_usb((u64)hdev->bus->busnum);
5852
5853	dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
5854			hdev->state, hdev->maxchild,
5855			/* NOTE: expects max 15 ports... */
5856			(u16) hub->change_bits[0],
5857			(u16) hub->event_bits[0]);
5858
5859	/* Lock the device, then check to see if we were
5860	 * disconnected while waiting for the lock to succeed. */
5861	usb_lock_device(hdev);
5862	if (unlikely(hub->disconnected))
5863		goto out_hdev_lock;
5864
5865	/* If the hub has died, clean up after it */
5866	if (hdev->state == USB_STATE_NOTATTACHED) {
5867		hub->error = -ENODEV;
5868		hub_quiesce(hub, HUB_DISCONNECT);
5869		goto out_hdev_lock;
5870	}
5871
5872	/* Autoresume */
5873	ret = usb_autopm_get_interface(intf);
5874	if (ret) {
5875		dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
5876		goto out_hdev_lock;
5877	}
5878
5879	/* If this is an inactive hub, do nothing */
5880	if (hub->quiescing)
5881		goto out_autopm;
5882
5883	if (hub->error) {
5884		dev_dbg(hub_dev, "resetting for error %d\n", hub->error);
5885
5886		ret = usb_reset_device(hdev);
5887		if (ret) {
5888			dev_dbg(hub_dev, "error resetting hub: %d\n", ret);
5889			goto out_autopm;
5890		}
5891
5892		hub->nerrors = 0;
5893		hub->error = 0;
5894	}
5895
5896	/* deal with port status changes */
5897	for (i = 1; i <= hdev->maxchild; i++) {
5898		struct usb_port *port_dev = hub->ports[i - 1];
5899
5900		if (test_bit(i, hub->event_bits)
5901				|| test_bit(i, hub->change_bits)
5902				|| test_bit(i, hub->wakeup_bits)) {
5903			/*
5904			 * The get_noresume and barrier ensure that if
5905			 * the port was in the process of resuming, we
5906			 * flush that work and keep the port active for
5907			 * the duration of the port_event().  However,
5908			 * if the port is runtime pm suspended
5909			 * (powered-off), we leave it in that state, run
5910			 * an abbreviated port_event(), and move on.
5911			 */
5912			pm_runtime_get_noresume(&port_dev->dev);
5913			pm_runtime_barrier(&port_dev->dev);
5914			usb_lock_port(port_dev);
5915			port_event(hub, i);
5916			usb_unlock_port(port_dev);
5917			pm_runtime_put_sync(&port_dev->dev);
5918		}
5919	}
5920
5921	/* deal with hub status changes */
5922	if (test_and_clear_bit(0, hub->event_bits) == 0)
5923		;	/* do nothing */
5924	else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
5925		dev_err(hub_dev, "get_hub_status failed\n");
5926	else {
5927		if (hubchange & HUB_CHANGE_LOCAL_POWER) {
5928			dev_dbg(hub_dev, "power change\n");
5929			clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
5930			if (hubstatus & HUB_STATUS_LOCAL_POWER)
5931				/* FIXME: Is this always true? */
5932				hub->limited_power = 1;
5933			else
5934				hub->limited_power = 0;
5935		}
5936		if (hubchange & HUB_CHANGE_OVERCURRENT) {
5937			u16 status = 0;
5938			u16 unused;
5939
5940			dev_dbg(hub_dev, "over-current change\n");
5941			clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
5942			msleep(500);	/* Cool down */
5943			hub_power_on(hub, true);
5944			hub_hub_status(hub, &status, &unused);
5945			if (status & HUB_STATUS_OVERCURRENT)
5946				dev_err(hub_dev, "over-current condition\n");
5947		}
5948	}
5949
5950out_autopm:
5951	/* Balance the usb_autopm_get_interface() above */
5952	usb_autopm_put_interface_no_suspend(intf);
5953out_hdev_lock:
5954	usb_unlock_device(hdev);
5955
5956	/* Balance the stuff in kick_hub_wq() and allow autosuspend */
5957	usb_autopm_put_interface(intf);
5958	hub_put(hub);
5959
5960	kcov_remote_stop();
5961}
5962
5963static const struct usb_device_id hub_id_table[] = {
5964    { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5965                   | USB_DEVICE_ID_MATCH_PRODUCT
5966                   | USB_DEVICE_ID_MATCH_INT_CLASS,
5967      .idVendor = USB_VENDOR_SMSC,
5968      .idProduct = USB_PRODUCT_USB5534B,
5969      .bInterfaceClass = USB_CLASS_HUB,
5970      .driver_info = HUB_QUIRK_DISABLE_AUTOSUSPEND},
5971    { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5972                   | USB_DEVICE_ID_MATCH_PRODUCT,
5973      .idVendor = USB_VENDOR_CYPRESS,
5974      .idProduct = USB_PRODUCT_CY7C65632,
5975      .driver_info = HUB_QUIRK_DISABLE_AUTOSUSPEND},
5976    { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5977			| USB_DEVICE_ID_MATCH_INT_CLASS,
5978      .idVendor = USB_VENDOR_GENESYS_LOGIC,
5979      .bInterfaceClass = USB_CLASS_HUB,
5980      .driver_info = HUB_QUIRK_CHECK_PORT_AUTOSUSPEND},
5981    { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5982			| USB_DEVICE_ID_MATCH_PRODUCT,
5983      .idVendor = USB_VENDOR_TEXAS_INSTRUMENTS,
5984      .idProduct = USB_PRODUCT_TUSB8041_USB2,
5985      .driver_info = HUB_QUIRK_DISABLE_AUTOSUSPEND},
5986    { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5987			| USB_DEVICE_ID_MATCH_PRODUCT,
5988      .idVendor = USB_VENDOR_TEXAS_INSTRUMENTS,
5989      .idProduct = USB_PRODUCT_TUSB8041_USB3,
5990      .driver_info = HUB_QUIRK_DISABLE_AUTOSUSPEND},
5991	{ .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5992			| USB_DEVICE_ID_MATCH_PRODUCT,
5993	  .idVendor = USB_VENDOR_MICROCHIP,
5994	  .idProduct = USB_PRODUCT_USB4913,
5995	  .driver_info = HUB_QUIRK_REDUCE_FRAME_INTR_BINTERVAL},
5996	{ .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5997			| USB_DEVICE_ID_MATCH_PRODUCT,
5998	  .idVendor = USB_VENDOR_MICROCHIP,
5999	  .idProduct = USB_PRODUCT_USB4914,
6000	  .driver_info = HUB_QUIRK_REDUCE_FRAME_INTR_BINTERVAL},
6001	{ .match_flags = USB_DEVICE_ID_MATCH_VENDOR
6002			| USB_DEVICE_ID_MATCH_PRODUCT,
6003	  .idVendor = USB_VENDOR_MICROCHIP,
6004	  .idProduct = USB_PRODUCT_USB4915,
6005	  .driver_info = HUB_QUIRK_REDUCE_FRAME_INTR_BINTERVAL},
6006    { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
6007      .bDeviceClass = USB_CLASS_HUB},
6008    { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
6009      .bInterfaceClass = USB_CLASS_HUB},
6010    { }						/* Terminating entry */
6011};
6012
6013MODULE_DEVICE_TABLE(usb, hub_id_table);
6014
6015static struct usb_driver hub_driver = {
6016	.name =		"hub",
6017	.probe =	hub_probe,
6018	.disconnect =	hub_disconnect,
6019	.suspend =	hub_suspend,
6020	.resume =	hub_resume,
6021	.reset_resume =	hub_reset_resume,
6022	.pre_reset =	hub_pre_reset,
6023	.post_reset =	hub_post_reset,
6024	.unlocked_ioctl = hub_ioctl,
6025	.id_table =	hub_id_table,
6026	.supports_autosuspend =	1,
6027};
6028
6029int usb_hub_init(void)
6030{
6031	if (usb_register(&hub_driver) < 0) {
6032		printk(KERN_ERR "%s: can't register hub driver\n",
6033			usbcore_name);
6034		return -1;
6035	}
6036
6037	/*
6038	 * The workqueue needs to be freezable to avoid interfering with
6039	 * USB-PERSIST port handover. Otherwise it might see that a full-speed
6040	 * device was gone before the EHCI controller had handed its port
6041	 * over to the companion full-speed controller.
6042	 */
6043	hub_wq = alloc_workqueue("usb_hub_wq", WQ_FREEZABLE, 0);
6044	if (hub_wq)
6045		return 0;
6046
6047	/* Fall through if kernel_thread failed */
6048	usb_deregister(&hub_driver);
6049	pr_err("%s: can't allocate workqueue for usb hub\n", usbcore_name);
6050
6051	return -1;
6052}
6053
6054void usb_hub_cleanup(void)
6055{
6056	destroy_workqueue(hub_wq);
6057
6058	/*
6059	 * Hub resources are freed for us by usb_deregister. It calls
6060	 * usb_driver_purge on every device which in turn calls that
6061	 * devices disconnect function if it is using this driver.
6062	 * The hub_disconnect function takes care of releasing the
6063	 * individual hub resources. -greg
6064	 */
6065	usb_deregister(&hub_driver);
6066} /* usb_hub_cleanup() */
6067
6068/**
6069 * hub_hc_release_resources - clear resources used by host controller
6070 * @udev: pointer to device being released
6071 *
6072 * Context: task context, might sleep
6073 *
6074 * Function releases the host controller resources in correct order before
6075 * making any operation on resuming usb device. The host controller resources
6076 * allocated for devices in tree should be released starting from the last
6077 * usb device in tree toward the root hub. This function is used only during
6078 * resuming device when usb device require reinitialization – that is, when
6079 * flag udev->reset_resume is set.
6080 *
6081 * This call is synchronous, and may not be used in an interrupt context.
6082 */
6083static void hub_hc_release_resources(struct usb_device *udev)
6084{
6085	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
6086	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
6087	int i;
6088
6089	/* Release up resources for all children before this device */
6090	for (i = 0; i < udev->maxchild; i++)
6091		if (hub->ports[i]->child)
6092			hub_hc_release_resources(hub->ports[i]->child);
6093
6094	if (hcd->driver->reset_device)
6095		hcd->driver->reset_device(hcd, udev);
6096}
6097
6098/**
6099 * usb_reset_and_verify_device - perform a USB port reset to reinitialize a device
6100 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
6101 *
6102 * WARNING - don't use this routine to reset a composite device
6103 * (one with multiple interfaces owned by separate drivers)!
6104 * Use usb_reset_device() instead.
6105 *
6106 * Do a port reset, reassign the device's address, and establish its
6107 * former operating configuration.  If the reset fails, or the device's
6108 * descriptors change from their values before the reset, or the original
6109 * configuration and altsettings cannot be restored, a flag will be set
6110 * telling hub_wq to pretend the device has been disconnected and then
6111 * re-connected.  All drivers will be unbound, and the device will be
6112 * re-enumerated and probed all over again.
6113 *
6114 * Return: 0 if the reset succeeded, -ENODEV if the device has been
6115 * flagged for logical disconnection, or some other negative error code
6116 * if the reset wasn't even attempted.
6117 *
6118 * Note:
6119 * The caller must own the device lock and the port lock, the latter is
6120 * taken by usb_reset_device().  For example, it's safe to use
6121 * usb_reset_device() from a driver probe() routine after downloading
6122 * new firmware.  For calls that might not occur during probe(), drivers
6123 * should lock the device using usb_lock_device_for_reset().
6124 *
6125 * Locking exception: This routine may also be called from within an
6126 * autoresume handler.  Such usage won't conflict with other tasks
6127 * holding the device lock because these tasks should always call
6128 * usb_autopm_resume_device(), thereby preventing any unwanted
6129 * autoresume.  The autoresume handler is expected to have already
6130 * acquired the port lock before calling this routine.
6131 */
6132static int usb_reset_and_verify_device(struct usb_device *udev)
6133{
6134	struct usb_device		*parent_hdev = udev->parent;
6135	struct usb_hub			*parent_hub;
6136	struct usb_hcd			*hcd = bus_to_hcd(udev->bus);
6137	struct usb_device_descriptor	descriptor;
6138	struct usb_host_bos		*bos;
6139	int				i, j, ret = 0;
6140	int				port1 = udev->portnum;
6141
6142	if (udev->state == USB_STATE_NOTATTACHED ||
6143			udev->state == USB_STATE_SUSPENDED) {
6144		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
6145				udev->state);
6146		return -EINVAL;
6147	}
6148
6149	if (!parent_hdev)
6150		return -EISDIR;
6151
6152	parent_hub = usb_hub_to_struct_hub(parent_hdev);
6153
6154	/* Disable USB2 hardware LPM.
6155	 * It will be re-enabled by the enumeration process.
6156	 */
6157	usb_disable_usb2_hardware_lpm(udev);
6158
 
 
 
 
 
 
 
 
 
 
6159	bos = udev->bos;
6160	udev->bos = NULL;
6161
6162	if (udev->reset_resume)
6163		hub_hc_release_resources(udev);
6164
6165	mutex_lock(hcd->address0_mutex);
6166
6167	for (i = 0; i < PORT_INIT_TRIES; ++i) {
6168		if (hub_port_stop_enumerate(parent_hub, port1, i)) {
6169			ret = -ENODEV;
6170			break;
6171		}
6172
6173		/* ep0 maxpacket size may change; let the HCD know about it.
6174		 * Other endpoints will be handled by re-enumeration. */
6175		usb_ep0_reinit(udev);
6176		ret = hub_port_init(parent_hub, udev, port1, i, &descriptor);
6177		if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
6178			break;
6179	}
6180	mutex_unlock(hcd->address0_mutex);
6181
6182	if (ret < 0)
6183		goto re_enumerate;
6184
6185	/* Device might have changed firmware (DFU or similar) */
6186	if (descriptors_changed(udev, &descriptor, bos)) {
6187		dev_info(&udev->dev, "device firmware changed\n");
 
6188		goto re_enumerate;
6189	}
6190
6191	/* Restore the device's previous configuration */
6192	if (!udev->actconfig)
6193		goto done;
6194
6195	mutex_lock(hcd->bandwidth_mutex);
6196	ret = usb_hcd_alloc_bandwidth(udev, udev->actconfig, NULL, NULL);
6197	if (ret < 0) {
6198		dev_warn(&udev->dev,
6199				"Busted HC?  Not enough HCD resources for "
6200				"old configuration.\n");
6201		mutex_unlock(hcd->bandwidth_mutex);
6202		goto re_enumerate;
6203	}
6204	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
6205			USB_REQ_SET_CONFIGURATION, 0,
6206			udev->actconfig->desc.bConfigurationValue, 0,
6207			NULL, 0, USB_CTRL_SET_TIMEOUT);
6208	if (ret < 0) {
6209		dev_err(&udev->dev,
6210			"can't restore configuration #%d (error=%d)\n",
6211			udev->actconfig->desc.bConfigurationValue, ret);
6212		mutex_unlock(hcd->bandwidth_mutex);
6213		goto re_enumerate;
6214	}
6215	mutex_unlock(hcd->bandwidth_mutex);
6216	usb_set_device_state(udev, USB_STATE_CONFIGURED);
6217
6218	/* Put interfaces back into the same altsettings as before.
6219	 * Don't bother to send the Set-Interface request for interfaces
6220	 * that were already in altsetting 0; besides being unnecessary,
6221	 * many devices can't handle it.  Instead just reset the host-side
6222	 * endpoint state.
6223	 */
6224	for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
6225		struct usb_host_config *config = udev->actconfig;
6226		struct usb_interface *intf = config->interface[i];
6227		struct usb_interface_descriptor *desc;
6228
6229		desc = &intf->cur_altsetting->desc;
6230		if (desc->bAlternateSetting == 0) {
6231			usb_disable_interface(udev, intf, true);
6232			usb_enable_interface(udev, intf, true);
6233			ret = 0;
6234		} else {
6235			/* Let the bandwidth allocation function know that this
6236			 * device has been reset, and it will have to use
6237			 * alternate setting 0 as the current alternate setting.
6238			 */
6239			intf->resetting_device = 1;
6240			ret = usb_set_interface(udev, desc->bInterfaceNumber,
6241					desc->bAlternateSetting);
6242			intf->resetting_device = 0;
6243		}
6244		if (ret < 0) {
6245			dev_err(&udev->dev, "failed to restore interface %d "
6246				"altsetting %d (error=%d)\n",
6247				desc->bInterfaceNumber,
6248				desc->bAlternateSetting,
6249				ret);
6250			goto re_enumerate;
6251		}
6252		/* Resetting also frees any allocated streams */
6253		for (j = 0; j < intf->cur_altsetting->desc.bNumEndpoints; j++)
6254			intf->cur_altsetting->endpoint[j].streams = 0;
6255	}
6256
6257done:
6258	/* Now that the alt settings are re-installed, enable LTM and LPM. */
6259	usb_enable_usb2_hardware_lpm(udev);
6260	usb_unlocked_enable_lpm(udev);
6261	usb_enable_ltm(udev);
6262	usb_release_bos_descriptor(udev);
6263	udev->bos = bos;
6264	return 0;
6265
6266re_enumerate:
6267	usb_release_bos_descriptor(udev);
6268	udev->bos = bos;
 
 
6269	hub_port_logical_disconnect(parent_hub, port1);
6270	return -ENODEV;
6271}
6272
6273/**
6274 * usb_reset_device - warn interface drivers and perform a USB port reset
6275 * @udev: device to reset (not in NOTATTACHED state)
6276 *
6277 * Warns all drivers bound to registered interfaces (using their pre_reset
6278 * method), performs the port reset, and then lets the drivers know that
6279 * the reset is over (using their post_reset method).
6280 *
6281 * Return: The same as for usb_reset_and_verify_device().
6282 * However, if a reset is already in progress (for instance, if a
6283 * driver doesn't have pre_reset() or post_reset() callbacks, and while
6284 * being unbound or re-bound during the ongoing reset its disconnect()
6285 * or probe() routine tries to perform a second, nested reset), the
6286 * routine returns -EINPROGRESS.
6287 *
6288 * Note:
6289 * The caller must own the device lock.  For example, it's safe to use
6290 * this from a driver probe() routine after downloading new firmware.
6291 * For calls that might not occur during probe(), drivers should lock
6292 * the device using usb_lock_device_for_reset().
6293 *
6294 * If an interface is currently being probed or disconnected, we assume
6295 * its driver knows how to handle resets.  For all other interfaces,
6296 * if the driver doesn't have pre_reset and post_reset methods then
6297 * we attempt to unbind it and rebind afterward.
6298 */
6299int usb_reset_device(struct usb_device *udev)
6300{
6301	int ret;
6302	int i;
6303	unsigned int noio_flag;
6304	struct usb_port *port_dev;
6305	struct usb_host_config *config = udev->actconfig;
6306	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
6307
6308	if (udev->state == USB_STATE_NOTATTACHED) {
6309		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
6310				udev->state);
6311		return -EINVAL;
6312	}
6313
6314	if (!udev->parent) {
6315		/* this requires hcd-specific logic; see ohci_restart() */
6316		dev_dbg(&udev->dev, "%s for root hub!\n", __func__);
6317		return -EISDIR;
6318	}
6319
6320	if (udev->reset_in_progress)
6321		return -EINPROGRESS;
6322	udev->reset_in_progress = 1;
6323
6324	port_dev = hub->ports[udev->portnum - 1];
6325
6326	/*
6327	 * Don't allocate memory with GFP_KERNEL in current
6328	 * context to avoid possible deadlock if usb mass
6329	 * storage interface or usbnet interface(iSCSI case)
6330	 * is included in current configuration. The easist
6331	 * approach is to do it for every device reset,
6332	 * because the device 'memalloc_noio' flag may have
6333	 * not been set before reseting the usb device.
6334	 */
6335	noio_flag = memalloc_noio_save();
6336
6337	/* Prevent autosuspend during the reset */
6338	usb_autoresume_device(udev);
6339
6340	if (config) {
6341		for (i = 0; i < config->desc.bNumInterfaces; ++i) {
6342			struct usb_interface *cintf = config->interface[i];
6343			struct usb_driver *drv;
6344			int unbind = 0;
6345
6346			if (cintf->dev.driver) {
6347				drv = to_usb_driver(cintf->dev.driver);
6348				if (drv->pre_reset && drv->post_reset)
6349					unbind = (drv->pre_reset)(cintf);
6350				else if (cintf->condition ==
6351						USB_INTERFACE_BOUND)
6352					unbind = 1;
6353				if (unbind)
6354					usb_forced_unbind_intf(cintf);
6355			}
6356		}
6357	}
6358
6359	usb_lock_port(port_dev);
6360	ret = usb_reset_and_verify_device(udev);
6361	usb_unlock_port(port_dev);
6362
6363	if (config) {
6364		for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
6365			struct usb_interface *cintf = config->interface[i];
6366			struct usb_driver *drv;
6367			int rebind = cintf->needs_binding;
6368
6369			if (!rebind && cintf->dev.driver) {
6370				drv = to_usb_driver(cintf->dev.driver);
6371				if (drv->post_reset)
6372					rebind = (drv->post_reset)(cintf);
6373				else if (cintf->condition ==
6374						USB_INTERFACE_BOUND)
6375					rebind = 1;
6376				if (rebind)
6377					cintf->needs_binding = 1;
6378			}
6379		}
6380
6381		/* If the reset failed, hub_wq will unbind drivers later */
6382		if (ret == 0)
6383			usb_unbind_and_rebind_marked_interfaces(udev);
6384	}
6385
6386	usb_autosuspend_device(udev);
6387	memalloc_noio_restore(noio_flag);
6388	udev->reset_in_progress = 0;
6389	return ret;
6390}
6391EXPORT_SYMBOL_GPL(usb_reset_device);
6392
6393
6394/**
6395 * usb_queue_reset_device - Reset a USB device from an atomic context
6396 * @iface: USB interface belonging to the device to reset
6397 *
6398 * This function can be used to reset a USB device from an atomic
6399 * context, where usb_reset_device() won't work (as it blocks).
6400 *
6401 * Doing a reset via this method is functionally equivalent to calling
6402 * usb_reset_device(), except for the fact that it is delayed to a
6403 * workqueue. This means that any drivers bound to other interfaces
6404 * might be unbound, as well as users from usbfs in user space.
6405 *
6406 * Corner cases:
6407 *
6408 * - Scheduling two resets at the same time from two different drivers
6409 *   attached to two different interfaces of the same device is
6410 *   possible; depending on how the driver attached to each interface
6411 *   handles ->pre_reset(), the second reset might happen or not.
6412 *
6413 * - If the reset is delayed so long that the interface is unbound from
6414 *   its driver, the reset will be skipped.
6415 *
6416 * - This function can be called during .probe().  It can also be called
6417 *   during .disconnect(), but doing so is pointless because the reset
6418 *   will not occur.  If you really want to reset the device during
6419 *   .disconnect(), call usb_reset_device() directly -- but watch out
6420 *   for nested unbinding issues!
6421 */
6422void usb_queue_reset_device(struct usb_interface *iface)
6423{
6424	if (schedule_work(&iface->reset_ws))
6425		usb_get_intf(iface);
6426}
6427EXPORT_SYMBOL_GPL(usb_queue_reset_device);
6428
6429/**
6430 * usb_hub_find_child - Get the pointer of child device
6431 * attached to the port which is specified by @port1.
6432 * @hdev: USB device belonging to the usb hub
6433 * @port1: port num to indicate which port the child device
6434 *	is attached to.
6435 *
6436 * USB drivers call this function to get hub's child device
6437 * pointer.
6438 *
6439 * Return: %NULL if input param is invalid and
6440 * child's usb_device pointer if non-NULL.
6441 */
6442struct usb_device *usb_hub_find_child(struct usb_device *hdev,
6443		int port1)
6444{
6445	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
6446
6447	if (port1 < 1 || port1 > hdev->maxchild)
6448		return NULL;
6449	return hub->ports[port1 - 1]->child;
6450}
6451EXPORT_SYMBOL_GPL(usb_hub_find_child);
6452
6453void usb_hub_adjust_deviceremovable(struct usb_device *hdev,
6454		struct usb_hub_descriptor *desc)
6455{
6456	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
6457	enum usb_port_connect_type connect_type;
6458	int i;
6459
6460	if (!hub)
6461		return;
6462
6463	if (!hub_is_superspeed(hdev)) {
6464		for (i = 1; i <= hdev->maxchild; i++) {
6465			struct usb_port *port_dev = hub->ports[i - 1];
6466
6467			connect_type = port_dev->connect_type;
6468			if (connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
6469				u8 mask = 1 << (i%8);
6470
6471				if (!(desc->u.hs.DeviceRemovable[i/8] & mask)) {
6472					dev_dbg(&port_dev->dev, "DeviceRemovable is changed to 1 according to platform information.\n");
6473					desc->u.hs.DeviceRemovable[i/8]	|= mask;
6474				}
6475			}
6476		}
6477	} else {
6478		u16 port_removable = le16_to_cpu(desc->u.ss.DeviceRemovable);
6479
6480		for (i = 1; i <= hdev->maxchild; i++) {
6481			struct usb_port *port_dev = hub->ports[i - 1];
6482
6483			connect_type = port_dev->connect_type;
6484			if (connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
6485				u16 mask = 1 << i;
6486
6487				if (!(port_removable & mask)) {
6488					dev_dbg(&port_dev->dev, "DeviceRemovable is changed to 1 according to platform information.\n");
6489					port_removable |= mask;
6490				}
6491			}
6492		}
6493
6494		desc->u.ss.DeviceRemovable = cpu_to_le16(port_removable);
6495	}
6496}
6497
6498#ifdef CONFIG_ACPI
6499/**
6500 * usb_get_hub_port_acpi_handle - Get the usb port's acpi handle
6501 * @hdev: USB device belonging to the usb hub
6502 * @port1: port num of the port
6503 *
6504 * Return: Port's acpi handle if successful, %NULL if params are
6505 * invalid.
6506 */
6507acpi_handle usb_get_hub_port_acpi_handle(struct usb_device *hdev,
6508	int port1)
6509{
6510	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
6511
6512	if (!hub)
6513		return NULL;
6514
6515	return ACPI_HANDLE(&hub->ports[port1 - 1]->dev);
6516}
6517#endif