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/otg.h>
  27#include <linux/usb/quirks.h>
  28#include <linux/workqueue.h>
  29#include <linux/mutex.h>
  30#include <linux/random.h>
  31#include <linux/pm_qos.h>
  32#include <linux/kobject.h>
  33
  34#include <linux/uaccess.h>
  35#include <asm/byteorder.h>
  36
  37#include "hub.h"
  38#include "otg_productlist.h"
  39
  40#define USB_VENDOR_GENESYS_LOGIC		0x05e3
  41#define USB_VENDOR_SMSC				0x0424
  42#define USB_PRODUCT_USB5534B			0x5534
  43#define HUB_QUIRK_CHECK_PORT_AUTOSUSPEND	0x01
  44#define HUB_QUIRK_DISABLE_AUTOSUSPEND		0x02
  45
  46#define USB_TP_TRANSMISSION_DELAY	40	/* ns */
  47#define USB_TP_TRANSMISSION_DELAY_MAX	65535	/* ns */
  48
  49/* Protect struct usb_device->state and ->children members
  50 * Note: Both are also protected by ->dev.sem, except that ->state can
  51 * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
  52static DEFINE_SPINLOCK(device_state_lock);
  53
  54/* workqueue to process hub events */
  55static struct workqueue_struct *hub_wq;
  56static void hub_event(struct work_struct *work);
  57
  58/* synchronize hub-port add/remove and peering operations */
  59DEFINE_MUTEX(usb_port_peer_mutex);
  60
  61/* cycle leds on hubs that aren't blinking for attention */
  62static bool blinkenlights;
  63module_param(blinkenlights, bool, S_IRUGO);
  64MODULE_PARM_DESC(blinkenlights, "true to cycle leds on hubs");
  65
  66/*
  67 * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
  68 * 10 seconds to send reply for the initial 64-byte descriptor request.
  69 */
  70/* define initial 64-byte descriptor request timeout in milliseconds */
  71static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
  72module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
  73MODULE_PARM_DESC(initial_descriptor_timeout,
  74		"initial 64-byte descriptor request timeout in milliseconds "
  75		"(default 5000 - 5.0 seconds)");
  76
  77/*
  78 * As of 2.6.10 we introduce a new USB device initialization scheme which
  79 * closely resembles the way Windows works.  Hopefully it will be compatible
  80 * with a wider range of devices than the old scheme.  However some previously
  81 * working devices may start giving rise to "device not accepting address"
  82 * errors; if that happens the user can try the old scheme by adjusting the
  83 * following module parameters.
  84 *
  85 * For maximum flexibility there are two boolean parameters to control the
  86 * hub driver's behavior.  On the first initialization attempt, if the
  87 * "old_scheme_first" parameter is set then the old scheme will be used,
  88 * otherwise the new scheme is used.  If that fails and "use_both_schemes"
  89 * is set, then the driver will make another attempt, using the other scheme.
  90 */
  91static bool old_scheme_first;
  92module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
  93MODULE_PARM_DESC(old_scheme_first,
  94		 "start with the old device initialization scheme");
  95
  96static bool use_both_schemes = true;
  97module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
  98MODULE_PARM_DESC(use_both_schemes,
  99		"try the other device initialization scheme if the "
 100		"first one fails");
 101
 102/* Mutual exclusion for EHCI CF initialization.  This interferes with
 103 * port reset on some companion controllers.
 104 */
 105DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
 106EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
 107
 108#define HUB_DEBOUNCE_TIMEOUT	2000
 109#define HUB_DEBOUNCE_STEP	  25
 110#define HUB_DEBOUNCE_STABLE	 100
 111
 112static void hub_release(struct kref *kref);
 113static int usb_reset_and_verify_device(struct usb_device *udev);
 114static int hub_port_disable(struct usb_hub *hub, int port1, int set_state);
 115static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
 116		u16 portstatus);
 117
 118static inline char *portspeed(struct usb_hub *hub, int portstatus)
 119{
 120	if (hub_is_superspeedplus(hub->hdev))
 121		return "10.0 Gb/s";
 122	if (hub_is_superspeed(hub->hdev))
 123		return "5.0 Gb/s";
 124	if (portstatus & USB_PORT_STAT_HIGH_SPEED)
 125		return "480 Mb/s";
 126	else if (portstatus & USB_PORT_STAT_LOW_SPEED)
 127		return "1.5 Mb/s";
 128	else
 129		return "12 Mb/s";
 130}
 131
 132/* Note that hdev or one of its children must be locked! */
 133struct usb_hub *usb_hub_to_struct_hub(struct usb_device *hdev)
 134{
 135	if (!hdev || !hdev->actconfig || !hdev->maxchild)
 136		return NULL;
 137	return usb_get_intfdata(hdev->actconfig->interface[0]);
 138}
 139
 140int usb_device_supports_lpm(struct usb_device *udev)
 141{
 142	/* Some devices have trouble with LPM */
 143	if (udev->quirks & USB_QUIRK_NO_LPM)
 144		return 0;
 145
 146	/* USB 2.1 (and greater) devices indicate LPM support through
 147	 * their USB 2.0 Extended Capabilities BOS descriptor.
 148	 */
 149	if (udev->speed == USB_SPEED_HIGH || udev->speed == USB_SPEED_FULL) {
 150		if (udev->bos->ext_cap &&
 151			(USB_LPM_SUPPORT &
 152			 le32_to_cpu(udev->bos->ext_cap->bmAttributes)))
 153			return 1;
 154		return 0;
 155	}
 156
 157	/*
 158	 * According to the USB 3.0 spec, all USB 3.0 devices must support LPM.
 159	 * However, there are some that don't, and they set the U1/U2 exit
 160	 * latencies to zero.
 161	 */
 162	if (!udev->bos->ss_cap) {
 163		dev_info(&udev->dev, "No LPM exit latency info found, disabling LPM.\n");
 164		return 0;
 165	}
 166
 167	if (udev->bos->ss_cap->bU1devExitLat == 0 &&
 168			udev->bos->ss_cap->bU2DevExitLat == 0) {
 169		if (udev->parent)
 170			dev_info(&udev->dev, "LPM exit latency is zeroed, disabling LPM.\n");
 171		else
 172			dev_info(&udev->dev, "We don't know the algorithms for LPM for this host, disabling LPM.\n");
 173		return 0;
 174	}
 175
 176	if (!udev->parent || udev->parent->lpm_capable)
 177		return 1;
 178	return 0;
 179}
 180
 181/*
 182 * Set the Maximum Exit Latency (MEL) for the host to initiate a transition from
 183 * either U1 or U2.
 184 */
 185static void usb_set_lpm_mel(struct usb_device *udev,
 186		struct usb3_lpm_parameters *udev_lpm_params,
 187		unsigned int udev_exit_latency,
 188		struct usb_hub *hub,
 189		struct usb3_lpm_parameters *hub_lpm_params,
 190		unsigned int hub_exit_latency)
 191{
 192	unsigned int total_mel;
 193	unsigned int device_mel;
 194	unsigned int hub_mel;
 195
 196	/*
 197	 * Calculate the time it takes to transition all links from the roothub
 198	 * to the parent hub into U0.  The parent hub must then decode the
 199	 * packet (hub header decode latency) to figure out which port it was
 200	 * bound for.
 201	 *
 202	 * The Hub Header decode latency is expressed in 0.1us intervals (0x1
 203	 * means 0.1us).  Multiply that by 100 to get nanoseconds.
 204	 */
 205	total_mel = hub_lpm_params->mel +
 206		(hub->descriptor->u.ss.bHubHdrDecLat * 100);
 207
 208	/*
 209	 * How long will it take to transition the downstream hub's port into
 210	 * U0?  The greater of either the hub exit latency or the device exit
 211	 * latency.
 212	 *
 213	 * The BOS U1/U2 exit latencies are expressed in 1us intervals.
 214	 * Multiply that by 1000 to get nanoseconds.
 215	 */
 216	device_mel = udev_exit_latency * 1000;
 217	hub_mel = hub_exit_latency * 1000;
 218	if (device_mel > hub_mel)
 219		total_mel += device_mel;
 220	else
 221		total_mel += hub_mel;
 222
 223	udev_lpm_params->mel = total_mel;
 224}
 225
 226/*
 227 * Set the maximum Device to Host Exit Latency (PEL) for the device to initiate
 228 * a transition from either U1 or U2.
 229 */
 230static void usb_set_lpm_pel(struct usb_device *udev,
 231		struct usb3_lpm_parameters *udev_lpm_params,
 232		unsigned int udev_exit_latency,
 233		struct usb_hub *hub,
 234		struct usb3_lpm_parameters *hub_lpm_params,
 235		unsigned int hub_exit_latency,
 236		unsigned int port_to_port_exit_latency)
 237{
 238	unsigned int first_link_pel;
 239	unsigned int hub_pel;
 240
 241	/*
 242	 * First, the device sends an LFPS to transition the link between the
 243	 * device and the parent hub into U0.  The exit latency is the bigger of
 244	 * the device exit latency or the hub exit latency.
 245	 */
 246	if (udev_exit_latency > hub_exit_latency)
 247		first_link_pel = udev_exit_latency * 1000;
 248	else
 249		first_link_pel = hub_exit_latency * 1000;
 250
 251	/*
 252	 * When the hub starts to receive the LFPS, there is a slight delay for
 253	 * it to figure out that one of the ports is sending an LFPS.  Then it
 254	 * will forward the LFPS to its upstream link.  The exit latency is the
 255	 * delay, plus the PEL that we calculated for this hub.
 256	 */
 257	hub_pel = port_to_port_exit_latency * 1000 + hub_lpm_params->pel;
 258
 259	/*
 260	 * According to figure C-7 in the USB 3.0 spec, the PEL for this device
 261	 * is the greater of the two exit latencies.
 262	 */
 263	if (first_link_pel > hub_pel)
 264		udev_lpm_params->pel = first_link_pel;
 265	else
 266		udev_lpm_params->pel = hub_pel;
 267}
 268
 269/*
 270 * Set the System Exit Latency (SEL) to indicate the total worst-case time from
 271 * when a device initiates a transition to U0, until when it will receive the
 272 * first packet from the host controller.
 273 *
 274 * Section C.1.5.1 describes the four components to this:
 275 *  - t1: device PEL
 276 *  - t2: time for the ERDY to make it from the device to the host.
 277 *  - t3: a host-specific delay to process the ERDY.
 278 *  - t4: time for the packet to make it from the host to the device.
 279 *
 280 * t3 is specific to both the xHCI host and the platform the host is integrated
 281 * into.  The Intel HW folks have said it's negligible, FIXME if a different
 282 * vendor says otherwise.
 283 */
 284static void usb_set_lpm_sel(struct usb_device *udev,
 285		struct usb3_lpm_parameters *udev_lpm_params)
 286{
 287	struct usb_device *parent;
 288	unsigned int num_hubs;
 289	unsigned int total_sel;
 290
 291	/* t1 = device PEL */
 292	total_sel = udev_lpm_params->pel;
 293	/* How many external hubs are in between the device & the root port. */
 294	for (parent = udev->parent, num_hubs = 0; parent->parent;
 295			parent = parent->parent)
 296		num_hubs++;
 297	/* t2 = 2.1us + 250ns * (num_hubs - 1) */
 298	if (num_hubs > 0)
 299		total_sel += 2100 + 250 * (num_hubs - 1);
 300
 301	/* t4 = 250ns * num_hubs */
 302	total_sel += 250 * num_hubs;
 303
 304	udev_lpm_params->sel = total_sel;
 305}
 306
 307static void usb_set_lpm_parameters(struct usb_device *udev)
 308{
 309	struct usb_hub *hub;
 310	unsigned int port_to_port_delay;
 311	unsigned int udev_u1_del;
 312	unsigned int udev_u2_del;
 313	unsigned int hub_u1_del;
 314	unsigned int hub_u2_del;
 315
 316	if (!udev->lpm_capable || udev->speed < USB_SPEED_SUPER)
 317		return;
 318
 319	hub = usb_hub_to_struct_hub(udev->parent);
 320	/* It doesn't take time to transition the roothub into U0, since it
 321	 * doesn't have an upstream link.
 322	 */
 323	if (!hub)
 324		return;
 325
 326	udev_u1_del = udev->bos->ss_cap->bU1devExitLat;
 327	udev_u2_del = le16_to_cpu(udev->bos->ss_cap->bU2DevExitLat);
 328	hub_u1_del = udev->parent->bos->ss_cap->bU1devExitLat;
 329	hub_u2_del = le16_to_cpu(udev->parent->bos->ss_cap->bU2DevExitLat);
 330
 331	usb_set_lpm_mel(udev, &udev->u1_params, udev_u1_del,
 332			hub, &udev->parent->u1_params, hub_u1_del);
 333
 334	usb_set_lpm_mel(udev, &udev->u2_params, udev_u2_del,
 335			hub, &udev->parent->u2_params, hub_u2_del);
 336
 337	/*
 338	 * Appendix C, section C.2.2.2, says that there is a slight delay from
 339	 * when the parent hub notices the downstream port is trying to
 340	 * transition to U0 to when the hub initiates a U0 transition on its
 341	 * upstream port.  The section says the delays are tPort2PortU1EL and
 342	 * tPort2PortU2EL, but it doesn't define what they are.
 343	 *
 344	 * The hub chapter, sections 10.4.2.4 and 10.4.2.5 seem to be talking
 345	 * about the same delays.  Use the maximum delay calculations from those
 346	 * sections.  For U1, it's tHubPort2PortExitLat, which is 1us max.  For
 347	 * U2, it's tHubPort2PortExitLat + U2DevExitLat - U1DevExitLat.  I
 348	 * assume the device exit latencies they are talking about are the hub
 349	 * exit latencies.
 350	 *
 351	 * What do we do if the U2 exit latency is less than the U1 exit
 352	 * latency?  It's possible, although not likely...
 353	 */
 354	port_to_port_delay = 1;
 355
 356	usb_set_lpm_pel(udev, &udev->u1_params, udev_u1_del,
 357			hub, &udev->parent->u1_params, hub_u1_del,
 358			port_to_port_delay);
 359
 360	if (hub_u2_del > hub_u1_del)
 361		port_to_port_delay = 1 + hub_u2_del - hub_u1_del;
 362	else
 363		port_to_port_delay = 1 + hub_u1_del;
 364
 365	usb_set_lpm_pel(udev, &udev->u2_params, udev_u2_del,
 366			hub, &udev->parent->u2_params, hub_u2_del,
 367			port_to_port_delay);
 368
 369	/* Now that we've got PEL, calculate SEL. */
 370	usb_set_lpm_sel(udev, &udev->u1_params);
 371	usb_set_lpm_sel(udev, &udev->u2_params);
 372}
 373
 374/* USB 2.0 spec Section 11.24.4.5 */
 375static int get_hub_descriptor(struct usb_device *hdev,
 376		struct usb_hub_descriptor *desc)
 377{
 378	int i, ret, size;
 379	unsigned dtype;
 380
 381	if (hub_is_superspeed(hdev)) {
 382		dtype = USB_DT_SS_HUB;
 383		size = USB_DT_SS_HUB_SIZE;
 384	} else {
 385		dtype = USB_DT_HUB;
 386		size = sizeof(struct usb_hub_descriptor);
 387	}
 388
 389	for (i = 0; i < 3; i++) {
 390		ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 391			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
 392			dtype << 8, 0, desc, size,
 393			USB_CTRL_GET_TIMEOUT);
 394		if (hub_is_superspeed(hdev)) {
 395			if (ret == size)
 396				return ret;
 397		} else if (ret >= USB_DT_HUB_NONVAR_SIZE + 2) {
 398			/* Make sure we have the DeviceRemovable field. */
 399			size = USB_DT_HUB_NONVAR_SIZE + desc->bNbrPorts / 8 + 1;
 400			if (ret < size)
 401				return -EMSGSIZE;
 402			return ret;
 403		}
 404	}
 405	return -EINVAL;
 406}
 407
 408/*
 409 * USB 2.0 spec Section 11.24.2.1
 410 */
 411static int clear_hub_feature(struct usb_device *hdev, int feature)
 412{
 413	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 414		USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
 415}
 416
 417/*
 418 * USB 2.0 spec Section 11.24.2.2
 419 */
 420int usb_clear_port_feature(struct usb_device *hdev, int port1, int feature)
 421{
 422	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 423		USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
 424		NULL, 0, 1000);
 425}
 426
 427/*
 428 * USB 2.0 spec Section 11.24.2.13
 429 */
 430static int set_port_feature(struct usb_device *hdev, int port1, int feature)
 431{
 432	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 433		USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
 434		NULL, 0, 1000);
 435}
 436
 437static char *to_led_name(int selector)
 438{
 439	switch (selector) {
 440	case HUB_LED_AMBER:
 441		return "amber";
 442	case HUB_LED_GREEN:
 443		return "green";
 444	case HUB_LED_OFF:
 445		return "off";
 446	case HUB_LED_AUTO:
 447		return "auto";
 448	default:
 449		return "??";
 450	}
 451}
 452
 453/*
 454 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
 455 * for info about using port indicators
 456 */
 457static void set_port_led(struct usb_hub *hub, int port1, int selector)
 458{
 459	struct usb_port *port_dev = hub->ports[port1 - 1];
 460	int status;
 461
 462	status = set_port_feature(hub->hdev, (selector << 8) | port1,
 463			USB_PORT_FEAT_INDICATOR);
 464	dev_dbg(&port_dev->dev, "indicator %s status %d\n",
 465		to_led_name(selector), status);
 466}
 467
 468#define	LED_CYCLE_PERIOD	((2*HZ)/3)
 469
 470static void led_work(struct work_struct *work)
 471{
 472	struct usb_hub		*hub =
 473		container_of(work, struct usb_hub, leds.work);
 474	struct usb_device	*hdev = hub->hdev;
 475	unsigned		i;
 476	unsigned		changed = 0;
 477	int			cursor = -1;
 478
 479	if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
 480		return;
 481
 482	for (i = 0; i < hdev->maxchild; i++) {
 483		unsigned	selector, mode;
 484
 485		/* 30%-50% duty cycle */
 486
 487		switch (hub->indicator[i]) {
 488		/* cycle marker */
 489		case INDICATOR_CYCLE:
 490			cursor = i;
 491			selector = HUB_LED_AUTO;
 492			mode = INDICATOR_AUTO;
 493			break;
 494		/* blinking green = sw attention */
 495		case INDICATOR_GREEN_BLINK:
 496			selector = HUB_LED_GREEN;
 497			mode = INDICATOR_GREEN_BLINK_OFF;
 498			break;
 499		case INDICATOR_GREEN_BLINK_OFF:
 500			selector = HUB_LED_OFF;
 501			mode = INDICATOR_GREEN_BLINK;
 502			break;
 503		/* blinking amber = hw attention */
 504		case INDICATOR_AMBER_BLINK:
 505			selector = HUB_LED_AMBER;
 506			mode = INDICATOR_AMBER_BLINK_OFF;
 507			break;
 508		case INDICATOR_AMBER_BLINK_OFF:
 509			selector = HUB_LED_OFF;
 510			mode = INDICATOR_AMBER_BLINK;
 511			break;
 512		/* blink green/amber = reserved */
 513		case INDICATOR_ALT_BLINK:
 514			selector = HUB_LED_GREEN;
 515			mode = INDICATOR_ALT_BLINK_OFF;
 516			break;
 517		case INDICATOR_ALT_BLINK_OFF:
 518			selector = HUB_LED_AMBER;
 519			mode = INDICATOR_ALT_BLINK;
 520			break;
 521		default:
 522			continue;
 523		}
 524		if (selector != HUB_LED_AUTO)
 525			changed = 1;
 526		set_port_led(hub, i + 1, selector);
 527		hub->indicator[i] = mode;
 528	}
 529	if (!changed && blinkenlights) {
 530		cursor++;
 531		cursor %= hdev->maxchild;
 532		set_port_led(hub, cursor + 1, HUB_LED_GREEN);
 533		hub->indicator[cursor] = INDICATOR_CYCLE;
 534		changed++;
 535	}
 536	if (changed)
 537		queue_delayed_work(system_power_efficient_wq,
 538				&hub->leds, LED_CYCLE_PERIOD);
 539}
 540
 541/* use a short timeout for hub/port status fetches */
 542#define	USB_STS_TIMEOUT		1000
 543#define	USB_STS_RETRIES		5
 544
 545/*
 546 * USB 2.0 spec Section 11.24.2.6
 547 */
 548static int get_hub_status(struct usb_device *hdev,
 549		struct usb_hub_status *data)
 550{
 551	int i, status = -ETIMEDOUT;
 552
 553	for (i = 0; i < USB_STS_RETRIES &&
 554			(status == -ETIMEDOUT || status == -EPIPE); i++) {
 555		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 556			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
 557			data, sizeof(*data), USB_STS_TIMEOUT);
 558	}
 559	return status;
 560}
 561
 562/*
 563 * USB 2.0 spec Section 11.24.2.7
 564 * USB 3.1 takes into use the wValue and wLength fields, spec Section 10.16.2.6
 565 */
 566static int get_port_status(struct usb_device *hdev, int port1,
 567			   void *data, u16 value, u16 length)
 568{
 569	int i, status = -ETIMEDOUT;
 570
 571	for (i = 0; i < USB_STS_RETRIES &&
 572			(status == -ETIMEDOUT || status == -EPIPE); i++) {
 573		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 574			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, value,
 575			port1, data, length, USB_STS_TIMEOUT);
 576	}
 577	return status;
 578}
 579
 580static int hub_ext_port_status(struct usb_hub *hub, int port1, int type,
 581			       u16 *status, u16 *change, u32 *ext_status)
 582{
 583	int ret;
 584	int len = 4;
 585
 586	if (type != HUB_PORT_STATUS)
 587		len = 8;
 588
 589	mutex_lock(&hub->status_mutex);
 590	ret = get_port_status(hub->hdev, port1, &hub->status->port, type, len);
 591	if (ret < len) {
 592		if (ret != -ENODEV)
 593			dev_err(hub->intfdev,
 594				"%s failed (err = %d)\n", __func__, ret);
 595		if (ret >= 0)
 596			ret = -EIO;
 597	} else {
 598		*status = le16_to_cpu(hub->status->port.wPortStatus);
 599		*change = le16_to_cpu(hub->status->port.wPortChange);
 600		if (type != HUB_PORT_STATUS && ext_status)
 601			*ext_status = le32_to_cpu(
 602				hub->status->port.dwExtPortStatus);
 603		ret = 0;
 604	}
 605	mutex_unlock(&hub->status_mutex);
 606	return ret;
 607}
 608
 609static int hub_port_status(struct usb_hub *hub, int port1,
 610		u16 *status, u16 *change)
 611{
 612	return hub_ext_port_status(hub, port1, HUB_PORT_STATUS,
 613				   status, change, NULL);
 614}
 615
 616static void hub_resubmit_irq_urb(struct usb_hub *hub)
 617{
 618	unsigned long flags;
 619	int status;
 620
 621	spin_lock_irqsave(&hub->irq_urb_lock, flags);
 622
 623	if (hub->quiescing) {
 624		spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
 625		return;
 626	}
 627
 628	status = usb_submit_urb(hub->urb, GFP_ATOMIC);
 629	if (status && status != -ENODEV && status != -EPERM &&
 630	    status != -ESHUTDOWN) {
 631		dev_err(hub->intfdev, "resubmit --> %d\n", status);
 632		mod_timer(&hub->irq_urb_retry, jiffies + HZ);
 633	}
 634
 635	spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
 636}
 637
 638static void hub_retry_irq_urb(struct timer_list *t)
 639{
 640	struct usb_hub *hub = from_timer(hub, t, irq_urb_retry);
 641
 642	hub_resubmit_irq_urb(hub);
 643}
 644
 645
 646static void kick_hub_wq(struct usb_hub *hub)
 647{
 648	struct usb_interface *intf;
 649
 650	if (hub->disconnected || work_pending(&hub->events))
 651		return;
 652
 653	/*
 654	 * Suppress autosuspend until the event is proceed.
 655	 *
 656	 * Be careful and make sure that the symmetric operation is
 657	 * always called. We are here only when there is no pending
 658	 * work for this hub. Therefore put the interface either when
 659	 * the new work is called or when it is canceled.
 660	 */
 661	intf = to_usb_interface(hub->intfdev);
 662	usb_autopm_get_interface_no_resume(intf);
 663	kref_get(&hub->kref);
 664
 665	if (queue_work(hub_wq, &hub->events))
 666		return;
 667
 668	/* the work has already been scheduled */
 669	usb_autopm_put_interface_async(intf);
 670	kref_put(&hub->kref, hub_release);
 671}
 672
 673void usb_kick_hub_wq(struct usb_device *hdev)
 674{
 675	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
 676
 677	if (hub)
 678		kick_hub_wq(hub);
 679}
 680
 681/*
 682 * Let the USB core know that a USB 3.0 device has sent a Function Wake Device
 683 * Notification, which indicates it had initiated remote wakeup.
 684 *
 685 * USB 3.0 hubs do not report the port link state change from U3 to U0 when the
 686 * device initiates resume, so the USB core will not receive notice of the
 687 * resume through the normal hub interrupt URB.
 688 */
 689void usb_wakeup_notification(struct usb_device *hdev,
 690		unsigned int portnum)
 691{
 692	struct usb_hub *hub;
 693	struct usb_port *port_dev;
 694
 695	if (!hdev)
 696		return;
 697
 698	hub = usb_hub_to_struct_hub(hdev);
 699	if (hub) {
 700		port_dev = hub->ports[portnum - 1];
 701		if (port_dev && port_dev->child)
 702			pm_wakeup_event(&port_dev->child->dev, 0);
 703
 704		set_bit(portnum, hub->wakeup_bits);
 705		kick_hub_wq(hub);
 706	}
 707}
 708EXPORT_SYMBOL_GPL(usb_wakeup_notification);
 709
 710/* completion function, fires on port status changes and various faults */
 711static void hub_irq(struct urb *urb)
 712{
 713	struct usb_hub *hub = urb->context;
 714	int status = urb->status;
 715	unsigned i;
 716	unsigned long bits;
 717
 718	switch (status) {
 719	case -ENOENT:		/* synchronous unlink */
 720	case -ECONNRESET:	/* async unlink */
 721	case -ESHUTDOWN:	/* hardware going away */
 722		return;
 723
 724	default:		/* presumably an error */
 725		/* Cause a hub reset after 10 consecutive errors */
 726		dev_dbg(hub->intfdev, "transfer --> %d\n", status);
 727		if ((++hub->nerrors < 10) || hub->error)
 728			goto resubmit;
 729		hub->error = status;
 730		fallthrough;
 731
 732	/* let hub_wq handle things */
 733	case 0:			/* we got data:  port status changed */
 734		bits = 0;
 735		for (i = 0; i < urb->actual_length; ++i)
 736			bits |= ((unsigned long) ((*hub->buffer)[i]))
 737					<< (i*8);
 738		hub->event_bits[0] = bits;
 739		break;
 740	}
 741
 742	hub->nerrors = 0;
 743
 744	/* Something happened, let hub_wq figure it out */
 745	kick_hub_wq(hub);
 746
 747resubmit:
 748	hub_resubmit_irq_urb(hub);
 749}
 750
 751/* USB 2.0 spec Section 11.24.2.3 */
 752static inline int
 753hub_clear_tt_buffer(struct usb_device *hdev, u16 devinfo, u16 tt)
 754{
 755	/* Need to clear both directions for control ep */
 756	if (((devinfo >> 11) & USB_ENDPOINT_XFERTYPE_MASK) ==
 757			USB_ENDPOINT_XFER_CONTROL) {
 758		int status = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 759				HUB_CLEAR_TT_BUFFER, USB_RT_PORT,
 760				devinfo ^ 0x8000, tt, NULL, 0, 1000);
 761		if (status)
 762			return status;
 763	}
 764	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 765			       HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
 766			       tt, NULL, 0, 1000);
 767}
 768
 769/*
 770 * enumeration blocks hub_wq for a long time. we use keventd instead, since
 771 * long blocking there is the exception, not the rule.  accordingly, HCDs
 772 * talking to TTs must queue control transfers (not just bulk and iso), so
 773 * both can talk to the same hub concurrently.
 774 */
 775static void hub_tt_work(struct work_struct *work)
 776{
 777	struct usb_hub		*hub =
 778		container_of(work, struct usb_hub, tt.clear_work);
 779	unsigned long		flags;
 780
 781	spin_lock_irqsave(&hub->tt.lock, flags);
 782	while (!list_empty(&hub->tt.clear_list)) {
 783		struct list_head	*next;
 784		struct usb_tt_clear	*clear;
 785		struct usb_device	*hdev = hub->hdev;
 786		const struct hc_driver	*drv;
 787		int			status;
 788
 789		next = hub->tt.clear_list.next;
 790		clear = list_entry(next, struct usb_tt_clear, clear_list);
 791		list_del(&clear->clear_list);
 792
 793		/* drop lock so HCD can concurrently report other TT errors */
 794		spin_unlock_irqrestore(&hub->tt.lock, flags);
 795		status = hub_clear_tt_buffer(hdev, clear->devinfo, clear->tt);
 796		if (status && status != -ENODEV)
 797			dev_err(&hdev->dev,
 798				"clear tt %d (%04x) error %d\n",
 799				clear->tt, clear->devinfo, status);
 800
 801		/* Tell the HCD, even if the operation failed */
 802		drv = clear->hcd->driver;
 803		if (drv->clear_tt_buffer_complete)
 804			(drv->clear_tt_buffer_complete)(clear->hcd, clear->ep);
 805
 806		kfree(clear);
 807		spin_lock_irqsave(&hub->tt.lock, flags);
 808	}
 809	spin_unlock_irqrestore(&hub->tt.lock, flags);
 810}
 811
 812/**
 813 * usb_hub_set_port_power - control hub port's power state
 814 * @hdev: USB device belonging to the usb hub
 815 * @hub: target hub
 816 * @port1: port index
 817 * @set: expected status
 818 *
 819 * call this function to control port's power via setting or
 820 * clearing the port's PORT_POWER feature.
 821 *
 822 * Return: 0 if successful. A negative error code otherwise.
 823 */
 824int usb_hub_set_port_power(struct usb_device *hdev, struct usb_hub *hub,
 825			   int port1, bool set)
 826{
 827	int ret;
 828
 829	if (set)
 830		ret = set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
 831	else
 832		ret = usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
 833
 834	if (ret)
 835		return ret;
 836
 837	if (set)
 838		set_bit(port1, hub->power_bits);
 839	else
 840		clear_bit(port1, hub->power_bits);
 841	return 0;
 842}
 843
 844/**
 845 * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
 846 * @urb: an URB associated with the failed or incomplete split transaction
 847 *
 848 * High speed HCDs use this to tell the hub driver that some split control or
 849 * bulk transaction failed in a way that requires clearing internal state of
 850 * a transaction translator.  This is normally detected (and reported) from
 851 * interrupt context.
 852 *
 853 * It may not be possible for that hub to handle additional full (or low)
 854 * speed transactions until that state is fully cleared out.
 855 *
 856 * Return: 0 if successful. A negative error code otherwise.
 857 */
 858int usb_hub_clear_tt_buffer(struct urb *urb)
 859{
 860	struct usb_device	*udev = urb->dev;
 861	int			pipe = urb->pipe;
 862	struct usb_tt		*tt = udev->tt;
 863	unsigned long		flags;
 864	struct usb_tt_clear	*clear;
 865
 866	/* we've got to cope with an arbitrary number of pending TT clears,
 867	 * since each TT has "at least two" buffers that can need it (and
 868	 * there can be many TTs per hub).  even if they're uncommon.
 869	 */
 870	clear = kmalloc(sizeof *clear, GFP_ATOMIC);
 871	if (clear == NULL) {
 872		dev_err(&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
 873		/* FIXME recover somehow ... RESET_TT? */
 874		return -ENOMEM;
 875	}
 876
 877	/* info that CLEAR_TT_BUFFER needs */
 878	clear->tt = tt->multi ? udev->ttport : 1;
 879	clear->devinfo = usb_pipeendpoint (pipe);
 880	clear->devinfo |= ((u16)udev->devaddr) << 4;
 881	clear->devinfo |= usb_pipecontrol(pipe)
 882			? (USB_ENDPOINT_XFER_CONTROL << 11)
 883			: (USB_ENDPOINT_XFER_BULK << 11);
 884	if (usb_pipein(pipe))
 885		clear->devinfo |= 1 << 15;
 886
 887	/* info for completion callback */
 888	clear->hcd = bus_to_hcd(udev->bus);
 889	clear->ep = urb->ep;
 890
 891	/* tell keventd to clear state for this TT */
 892	spin_lock_irqsave(&tt->lock, flags);
 893	list_add_tail(&clear->clear_list, &tt->clear_list);
 894	schedule_work(&tt->clear_work);
 895	spin_unlock_irqrestore(&tt->lock, flags);
 896	return 0;
 897}
 898EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer);
 899
 900static void hub_power_on(struct usb_hub *hub, bool do_delay)
 901{
 902	int port1;
 903
 904	/* Enable power on each port.  Some hubs have reserved values
 905	 * of LPSM (> 2) in their descriptors, even though they are
 906	 * USB 2.0 hubs.  Some hubs do not implement port-power switching
 907	 * but only emulate it.  In all cases, the ports won't work
 908	 * unless we send these messages to the hub.
 909	 */
 910	if (hub_is_port_power_switchable(hub))
 911		dev_dbg(hub->intfdev, "enabling power on all ports\n");
 912	else
 913		dev_dbg(hub->intfdev, "trying to enable port power on "
 914				"non-switchable hub\n");
 915	for (port1 = 1; port1 <= hub->hdev->maxchild; port1++)
 916		if (test_bit(port1, hub->power_bits))
 917			set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
 918		else
 919			usb_clear_port_feature(hub->hdev, port1,
 920						USB_PORT_FEAT_POWER);
 921	if (do_delay)
 922		msleep(hub_power_on_good_delay(hub));
 923}
 924
 925static int hub_hub_status(struct usb_hub *hub,
 926		u16 *status, u16 *change)
 927{
 928	int ret;
 929
 930	mutex_lock(&hub->status_mutex);
 931	ret = get_hub_status(hub->hdev, &hub->status->hub);
 932	if (ret < 0) {
 933		if (ret != -ENODEV)
 934			dev_err(hub->intfdev,
 935				"%s failed (err = %d)\n", __func__, ret);
 936	} else {
 937		*status = le16_to_cpu(hub->status->hub.wHubStatus);
 938		*change = le16_to_cpu(hub->status->hub.wHubChange);
 939		ret = 0;
 940	}
 941	mutex_unlock(&hub->status_mutex);
 942	return ret;
 943}
 944
 945static int hub_set_port_link_state(struct usb_hub *hub, int port1,
 946			unsigned int link_status)
 947{
 948	return set_port_feature(hub->hdev,
 949			port1 | (link_status << 3),
 950			USB_PORT_FEAT_LINK_STATE);
 951}
 952
 953/*
 954 * Disable a port and mark a logical connect-change event, so that some
 955 * time later hub_wq will disconnect() any existing usb_device on the port
 956 * and will re-enumerate if there actually is a device attached.
 957 */
 958static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
 959{
 960	dev_dbg(&hub->ports[port1 - 1]->dev, "logical disconnect\n");
 961	hub_port_disable(hub, port1, 1);
 962
 963	/* FIXME let caller ask to power down the port:
 964	 *  - some devices won't enumerate without a VBUS power cycle
 965	 *  - SRP saves power that way
 966	 *  - ... new call, TBD ...
 967	 * That's easy if this hub can switch power per-port, and
 968	 * hub_wq reactivates the port later (timer, SRP, etc).
 969	 * Powerdown must be optional, because of reset/DFU.
 970	 */
 971
 972	set_bit(port1, hub->change_bits);
 973	kick_hub_wq(hub);
 974}
 975
 976/**
 977 * usb_remove_device - disable a device's port on its parent hub
 978 * @udev: device to be disabled and removed
 979 * Context: @udev locked, must be able to sleep.
 980 *
 981 * After @udev's port has been disabled, hub_wq is notified and it will
 982 * see that the device has been disconnected.  When the device is
 983 * physically unplugged and something is plugged in, the events will
 984 * be received and processed normally.
 985 *
 986 * Return: 0 if successful. A negative error code otherwise.
 987 */
 988int usb_remove_device(struct usb_device *udev)
 989{
 990	struct usb_hub *hub;
 991	struct usb_interface *intf;
 992	int ret;
 993
 994	if (!udev->parent)	/* Can't remove a root hub */
 995		return -EINVAL;
 996	hub = usb_hub_to_struct_hub(udev->parent);
 997	intf = to_usb_interface(hub->intfdev);
 998
 999	ret = usb_autopm_get_interface(intf);
1000	if (ret < 0)
1001		return ret;
1002
1003	set_bit(udev->portnum, hub->removed_bits);
1004	hub_port_logical_disconnect(hub, udev->portnum);
1005	usb_autopm_put_interface(intf);
1006	return 0;
1007}
1008
1009enum hub_activation_type {
1010	HUB_INIT, HUB_INIT2, HUB_INIT3,		/* INITs must come first */
1011	HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
1012};
1013
1014static void hub_init_func2(struct work_struct *ws);
1015static void hub_init_func3(struct work_struct *ws);
1016
1017static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
1018{
1019	struct usb_device *hdev = hub->hdev;
1020	struct usb_hcd *hcd;
1021	int ret;
1022	int port1;
1023	int status;
1024	bool need_debounce_delay = false;
1025	unsigned delay;
1026
1027	/* Continue a partial initialization */
1028	if (type == HUB_INIT2 || type == HUB_INIT3) {
1029		device_lock(&hdev->dev);
1030
1031		/* Was the hub disconnected while we were waiting? */
1032		if (hub->disconnected)
1033			goto disconnected;
1034		if (type == HUB_INIT2)
1035			goto init2;
1036		goto init3;
1037	}
1038	kref_get(&hub->kref);
1039
1040	/* The superspeed hub except for root hub has to use Hub Depth
1041	 * value as an offset into the route string to locate the bits
1042	 * it uses to determine the downstream port number. So hub driver
1043	 * should send a set hub depth request to superspeed hub after
1044	 * the superspeed hub is set configuration in initialization or
1045	 * reset procedure.
1046	 *
1047	 * After a resume, port power should still be on.
1048	 * For any other type of activation, turn it on.
1049	 */
1050	if (type != HUB_RESUME) {
1051		if (hdev->parent && hub_is_superspeed(hdev)) {
1052			ret = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
1053					HUB_SET_DEPTH, USB_RT_HUB,
1054					hdev->level - 1, 0, NULL, 0,
1055					USB_CTRL_SET_TIMEOUT);
1056			if (ret < 0)
1057				dev_err(hub->intfdev,
1058						"set hub depth failed\n");
1059		}
1060
1061		/* Speed up system boot by using a delayed_work for the
1062		 * hub's initial power-up delays.  This is pretty awkward
1063		 * and the implementation looks like a home-brewed sort of
1064		 * setjmp/longjmp, but it saves at least 100 ms for each
1065		 * root hub (assuming usbcore is compiled into the kernel
1066		 * rather than as a module).  It adds up.
1067		 *
1068		 * This can't be done for HUB_RESUME or HUB_RESET_RESUME
1069		 * because for those activation types the ports have to be
1070		 * operational when we return.  In theory this could be done
1071		 * for HUB_POST_RESET, but it's easier not to.
1072		 */
1073		if (type == HUB_INIT) {
1074			delay = hub_power_on_good_delay(hub);
1075
1076			hub_power_on(hub, false);
1077			INIT_DELAYED_WORK(&hub->init_work, hub_init_func2);
1078			queue_delayed_work(system_power_efficient_wq,
1079					&hub->init_work,
1080					msecs_to_jiffies(delay));
1081
1082			/* Suppress autosuspend until init is done */
1083			usb_autopm_get_interface_no_resume(
1084					to_usb_interface(hub->intfdev));
1085			return;		/* Continues at init2: below */
1086		} else if (type == HUB_RESET_RESUME) {
1087			/* The internal host controller state for the hub device
1088			 * may be gone after a host power loss on system resume.
1089			 * Update the device's info so the HW knows it's a hub.
1090			 */
1091			hcd = bus_to_hcd(hdev->bus);
1092			if (hcd->driver->update_hub_device) {
1093				ret = hcd->driver->update_hub_device(hcd, hdev,
1094						&hub->tt, GFP_NOIO);
1095				if (ret < 0) {
1096					dev_err(hub->intfdev,
1097						"Host not accepting hub info update\n");
1098					dev_err(hub->intfdev,
1099						"LS/FS devices and hubs may not work under this hub\n");
1100				}
1101			}
1102			hub_power_on(hub, true);
1103		} else {
1104			hub_power_on(hub, true);
1105		}
1106	}
1107 init2:
1108
1109	/*
1110	 * Check each port and set hub->change_bits to let hub_wq know
1111	 * which ports need attention.
1112	 */
1113	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
1114		struct usb_port *port_dev = hub->ports[port1 - 1];
1115		struct usb_device *udev = port_dev->child;
1116		u16 portstatus, portchange;
1117
1118		portstatus = portchange = 0;
1119		status = hub_port_status(hub, port1, &portstatus, &portchange);
1120		if (status)
1121			goto abort;
1122
1123		if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
1124			dev_dbg(&port_dev->dev, "status %04x change %04x\n",
1125					portstatus, portchange);
1126
1127		/*
1128		 * After anything other than HUB_RESUME (i.e., initialization
1129		 * or any sort of reset), every port should be disabled.
1130		 * Unconnected ports should likewise be disabled (paranoia),
1131		 * and so should ports for which we have no usb_device.
1132		 */
1133		if ((portstatus & USB_PORT_STAT_ENABLE) && (
1134				type != HUB_RESUME ||
1135				!(portstatus & USB_PORT_STAT_CONNECTION) ||
1136				!udev ||
1137				udev->state == USB_STATE_NOTATTACHED)) {
1138			/*
1139			 * USB3 protocol ports will automatically transition
1140			 * to Enabled state when detect an USB3.0 device attach.
1141			 * Do not disable USB3 protocol ports, just pretend
1142			 * power was lost
1143			 */
1144			portstatus &= ~USB_PORT_STAT_ENABLE;
1145			if (!hub_is_superspeed(hdev))
1146				usb_clear_port_feature(hdev, port1,
1147						   USB_PORT_FEAT_ENABLE);
1148		}
1149
1150		/* Make sure a warm-reset request is handled by port_event */
1151		if (type == HUB_RESUME &&
1152		    hub_port_warm_reset_required(hub, port1, portstatus))
1153			set_bit(port1, hub->event_bits);
1154
1155		/*
1156		 * Add debounce if USB3 link is in polling/link training state.
1157		 * Link will automatically transition to Enabled state after
1158		 * link training completes.
1159		 */
1160		if (hub_is_superspeed(hdev) &&
1161		    ((portstatus & USB_PORT_STAT_LINK_STATE) ==
1162						USB_SS_PORT_LS_POLLING))
1163			need_debounce_delay = true;
1164
1165		/* Clear status-change flags; we'll debounce later */
1166		if (portchange & USB_PORT_STAT_C_CONNECTION) {
1167			need_debounce_delay = true;
1168			usb_clear_port_feature(hub->hdev, port1,
1169					USB_PORT_FEAT_C_CONNECTION);
1170		}
1171		if (portchange & USB_PORT_STAT_C_ENABLE) {
1172			need_debounce_delay = true;
1173			usb_clear_port_feature(hub->hdev, port1,
1174					USB_PORT_FEAT_C_ENABLE);
1175		}
1176		if (portchange & USB_PORT_STAT_C_RESET) {
1177			need_debounce_delay = true;
1178			usb_clear_port_feature(hub->hdev, port1,
1179					USB_PORT_FEAT_C_RESET);
1180		}
1181		if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
1182				hub_is_superspeed(hub->hdev)) {
1183			need_debounce_delay = true;
1184			usb_clear_port_feature(hub->hdev, port1,
1185					USB_PORT_FEAT_C_BH_PORT_RESET);
1186		}
1187		/* We can forget about a "removed" device when there's a
1188		 * physical disconnect or the connect status changes.
1189		 */
1190		if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
1191				(portchange & USB_PORT_STAT_C_CONNECTION))
1192			clear_bit(port1, hub->removed_bits);
1193
1194		if (!udev || udev->state == USB_STATE_NOTATTACHED) {
1195			/* Tell hub_wq to disconnect the device or
1196			 * check for a new connection or over current condition.
1197			 * Based on USB2.0 Spec Section 11.12.5,
1198			 * C_PORT_OVER_CURRENT could be set while
1199			 * PORT_OVER_CURRENT is not. So check for any of them.
1200			 */
1201			if (udev || (portstatus & USB_PORT_STAT_CONNECTION) ||
1202			    (portchange & USB_PORT_STAT_C_CONNECTION) ||
1203			    (portstatus & USB_PORT_STAT_OVERCURRENT) ||
1204			    (portchange & USB_PORT_STAT_C_OVERCURRENT))
1205				set_bit(port1, hub->change_bits);
1206
1207		} else if (portstatus & USB_PORT_STAT_ENABLE) {
1208			bool port_resumed = (portstatus &
1209					USB_PORT_STAT_LINK_STATE) ==
1210				USB_SS_PORT_LS_U0;
1211			/* The power session apparently survived the resume.
1212			 * If there was an overcurrent or suspend change
1213			 * (i.e., remote wakeup request), have hub_wq
1214			 * take care of it.  Look at the port link state
1215			 * for USB 3.0 hubs, since they don't have a suspend
1216			 * change bit, and they don't set the port link change
1217			 * bit on device-initiated resume.
1218			 */
1219			if (portchange || (hub_is_superspeed(hub->hdev) &&
1220						port_resumed))
1221				set_bit(port1, hub->change_bits);
1222
1223		} else if (udev->persist_enabled) {
1224#ifdef CONFIG_PM
1225			udev->reset_resume = 1;
1226#endif
1227			/* Don't set the change_bits when the device
1228			 * was powered off.
1229			 */
1230			if (test_bit(port1, hub->power_bits))
1231				set_bit(port1, hub->change_bits);
1232
1233		} else {
1234			/* The power session is gone; tell hub_wq */
1235			usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1236			set_bit(port1, hub->change_bits);
1237		}
1238	}
1239
1240	/* If no port-status-change flags were set, we don't need any
1241	 * debouncing.  If flags were set we can try to debounce the
1242	 * ports all at once right now, instead of letting hub_wq do them
1243	 * one at a time later on.
1244	 *
1245	 * If any port-status changes do occur during this delay, hub_wq
1246	 * will see them later and handle them normally.
1247	 */
1248	if (need_debounce_delay) {
1249		delay = HUB_DEBOUNCE_STABLE;
1250
1251		/* Don't do a long sleep inside a workqueue routine */
1252		if (type == HUB_INIT2) {
1253			INIT_DELAYED_WORK(&hub->init_work, hub_init_func3);
1254			queue_delayed_work(system_power_efficient_wq,
1255					&hub->init_work,
1256					msecs_to_jiffies(delay));
1257			device_unlock(&hdev->dev);
1258			return;		/* Continues at init3: below */
1259		} else {
1260			msleep(delay);
1261		}
1262	}
1263 init3:
1264	hub->quiescing = 0;
1265
1266	status = usb_submit_urb(hub->urb, GFP_NOIO);
1267	if (status < 0)
1268		dev_err(hub->intfdev, "activate --> %d\n", status);
1269	if (hub->has_indicators && blinkenlights)
1270		queue_delayed_work(system_power_efficient_wq,
1271				&hub->leds, LED_CYCLE_PERIOD);
1272
1273	/* Scan all ports that need attention */
1274	kick_hub_wq(hub);
1275 abort:
1276	if (type == HUB_INIT2 || type == HUB_INIT3) {
1277		/* Allow autosuspend if it was suppressed */
1278 disconnected:
1279		usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
1280		device_unlock(&hdev->dev);
1281	}
1282
1283	kref_put(&hub->kref, hub_release);
1284}
1285
1286/* Implement the continuations for the delays above */
1287static void hub_init_func2(struct work_struct *ws)
1288{
1289	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1290
1291	hub_activate(hub, HUB_INIT2);
1292}
1293
1294static void hub_init_func3(struct work_struct *ws)
1295{
1296	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1297
1298	hub_activate(hub, HUB_INIT3);
1299}
1300
1301enum hub_quiescing_type {
1302	HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
1303};
1304
1305static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
1306{
1307	struct usb_device *hdev = hub->hdev;
1308	unsigned long flags;
1309	int i;
1310
1311	/* hub_wq and related activity won't re-trigger */
1312	spin_lock_irqsave(&hub->irq_urb_lock, flags);
1313	hub->quiescing = 1;
1314	spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
1315
1316	if (type != HUB_SUSPEND) {
1317		/* Disconnect all the children */
1318		for (i = 0; i < hdev->maxchild; ++i) {
1319			if (hub->ports[i]->child)
1320				usb_disconnect(&hub->ports[i]->child);
1321		}
1322	}
1323
1324	/* Stop hub_wq and related activity */
1325	del_timer_sync(&hub->irq_urb_retry);
1326	usb_kill_urb(hub->urb);
1327	if (hub->has_indicators)
1328		cancel_delayed_work_sync(&hub->leds);
1329	if (hub->tt.hub)
1330		flush_work(&hub->tt.clear_work);
1331}
1332
1333static void hub_pm_barrier_for_all_ports(struct usb_hub *hub)
1334{
1335	int i;
1336
1337	for (i = 0; i < hub->hdev->maxchild; ++i)
1338		pm_runtime_barrier(&hub->ports[i]->dev);
1339}
1340
1341/* caller has locked the hub device */
1342static int hub_pre_reset(struct usb_interface *intf)
1343{
1344	struct usb_hub *hub = usb_get_intfdata(intf);
1345
1346	hub_quiesce(hub, HUB_PRE_RESET);
1347	hub->in_reset = 1;
1348	hub_pm_barrier_for_all_ports(hub);
1349	return 0;
1350}
1351
1352/* caller has locked the hub device */
1353static int hub_post_reset(struct usb_interface *intf)
1354{
1355	struct usb_hub *hub = usb_get_intfdata(intf);
1356
1357	hub->in_reset = 0;
1358	hub_pm_barrier_for_all_ports(hub);
1359	hub_activate(hub, HUB_POST_RESET);
1360	return 0;
1361}
1362
1363static int hub_configure(struct usb_hub *hub,
1364	struct usb_endpoint_descriptor *endpoint)
1365{
1366	struct usb_hcd *hcd;
1367	struct usb_device *hdev = hub->hdev;
1368	struct device *hub_dev = hub->intfdev;
1369	u16 hubstatus, hubchange;
1370	u16 wHubCharacteristics;
1371	unsigned int pipe;
1372	int maxp, ret, i;
1373	char *message = "out of memory";
1374	unsigned unit_load;
1375	unsigned full_load;
1376	unsigned maxchild;
1377
1378	hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
1379	if (!hub->buffer) {
1380		ret = -ENOMEM;
1381		goto fail;
1382	}
1383
1384	hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
1385	if (!hub->status) {
1386		ret = -ENOMEM;
1387		goto fail;
1388	}
1389	mutex_init(&hub->status_mutex);
1390
1391	hub->descriptor = kzalloc(sizeof(*hub->descriptor), GFP_KERNEL);
1392	if (!hub->descriptor) {
1393		ret = -ENOMEM;
1394		goto fail;
1395	}
1396
1397	/* Request the entire hub descriptor.
1398	 * hub->descriptor can handle USB_MAXCHILDREN ports,
1399	 * but a (non-SS) hub can/will return fewer bytes here.
1400	 */
1401	ret = get_hub_descriptor(hdev, hub->descriptor);
1402	if (ret < 0) {
1403		message = "can't read hub descriptor";
1404		goto fail;
1405	}
1406
1407	maxchild = USB_MAXCHILDREN;
1408	if (hub_is_superspeed(hdev))
1409		maxchild = min_t(unsigned, maxchild, USB_SS_MAXPORTS);
1410
1411	if (hub->descriptor->bNbrPorts > maxchild) {
1412		message = "hub has too many ports!";
1413		ret = -ENODEV;
1414		goto fail;
1415	} else if (hub->descriptor->bNbrPorts == 0) {
1416		message = "hub doesn't have any ports!";
1417		ret = -ENODEV;
1418		goto fail;
1419	}
1420
1421	/*
1422	 * Accumulate wHubDelay + 40ns for every hub in the tree of devices.
1423	 * The resulting value will be used for SetIsochDelay() request.
1424	 */
1425	if (hub_is_superspeed(hdev) || hub_is_superspeedplus(hdev)) {
1426		u32 delay = __le16_to_cpu(hub->descriptor->u.ss.wHubDelay);
1427
1428		if (hdev->parent)
1429			delay += hdev->parent->hub_delay;
1430
1431		delay += USB_TP_TRANSMISSION_DELAY;
1432		hdev->hub_delay = min_t(u32, delay, USB_TP_TRANSMISSION_DELAY_MAX);
1433	}
1434
1435	maxchild = hub->descriptor->bNbrPorts;
1436	dev_info(hub_dev, "%d port%s detected\n", maxchild,
1437			(maxchild == 1) ? "" : "s");
1438
1439	hub->ports = kcalloc(maxchild, sizeof(struct usb_port *), GFP_KERNEL);
1440	if (!hub->ports) {
1441		ret = -ENOMEM;
1442		goto fail;
1443	}
1444
1445	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
1446	if (hub_is_superspeed(hdev)) {
1447		unit_load = 150;
1448		full_load = 900;
1449	} else {
1450		unit_load = 100;
1451		full_load = 500;
1452	}
1453
1454	/* FIXME for USB 3.0, skip for now */
1455	if ((wHubCharacteristics & HUB_CHAR_COMPOUND) &&
1456			!(hub_is_superspeed(hdev))) {
1457		char	portstr[USB_MAXCHILDREN + 1];
1458
1459		for (i = 0; i < maxchild; i++)
1460			portstr[i] = hub->descriptor->u.hs.DeviceRemovable
1461				    [((i + 1) / 8)] & (1 << ((i + 1) % 8))
1462				? 'F' : 'R';
1463		portstr[maxchild] = 0;
1464		dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
1465	} else
1466		dev_dbg(hub_dev, "standalone hub\n");
1467
1468	switch (wHubCharacteristics & HUB_CHAR_LPSM) {
1469	case HUB_CHAR_COMMON_LPSM:
1470		dev_dbg(hub_dev, "ganged power switching\n");
1471		break;
1472	case HUB_CHAR_INDV_PORT_LPSM:
1473		dev_dbg(hub_dev, "individual port power switching\n");
1474		break;
1475	case HUB_CHAR_NO_LPSM:
1476	case HUB_CHAR_LPSM:
1477		dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
1478		break;
1479	}
1480
1481	switch (wHubCharacteristics & HUB_CHAR_OCPM) {
1482	case HUB_CHAR_COMMON_OCPM:
1483		dev_dbg(hub_dev, "global over-current protection\n");
1484		break;
1485	case HUB_CHAR_INDV_PORT_OCPM:
1486		dev_dbg(hub_dev, "individual port over-current protection\n");
1487		break;
1488	case HUB_CHAR_NO_OCPM:
1489	case HUB_CHAR_OCPM:
1490		dev_dbg(hub_dev, "no over-current protection\n");
1491		break;
1492	}
1493
1494	spin_lock_init(&hub->tt.lock);
1495	INIT_LIST_HEAD(&hub->tt.clear_list);
1496	INIT_WORK(&hub->tt.clear_work, hub_tt_work);
1497	switch (hdev->descriptor.bDeviceProtocol) {
1498	case USB_HUB_PR_FS:
1499		break;
1500	case USB_HUB_PR_HS_SINGLE_TT:
1501		dev_dbg(hub_dev, "Single TT\n");
1502		hub->tt.hub = hdev;
1503		break;
1504	case USB_HUB_PR_HS_MULTI_TT:
1505		ret = usb_set_interface(hdev, 0, 1);
1506		if (ret == 0) {
1507			dev_dbg(hub_dev, "TT per port\n");
1508			hub->tt.multi = 1;
1509		} else
1510			dev_err(hub_dev, "Using single TT (err %d)\n",
1511				ret);
1512		hub->tt.hub = hdev;
1513		break;
1514	case USB_HUB_PR_SS:
1515		/* USB 3.0 hubs don't have a TT */
1516		break;
1517	default:
1518		dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
1519			hdev->descriptor.bDeviceProtocol);
1520		break;
1521	}
1522
1523	/* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
1524	switch (wHubCharacteristics & HUB_CHAR_TTTT) {
1525	case HUB_TTTT_8_BITS:
1526		if (hdev->descriptor.bDeviceProtocol != 0) {
1527			hub->tt.think_time = 666;
1528			dev_dbg(hub_dev, "TT requires at most %d "
1529					"FS bit times (%d ns)\n",
1530				8, hub->tt.think_time);
1531		}
1532		break;
1533	case HUB_TTTT_16_BITS:
1534		hub->tt.think_time = 666 * 2;
1535		dev_dbg(hub_dev, "TT requires at most %d "
1536				"FS bit times (%d ns)\n",
1537			16, hub->tt.think_time);
1538		break;
1539	case HUB_TTTT_24_BITS:
1540		hub->tt.think_time = 666 * 3;
1541		dev_dbg(hub_dev, "TT requires at most %d "
1542				"FS bit times (%d ns)\n",
1543			24, hub->tt.think_time);
1544		break;
1545	case HUB_TTTT_32_BITS:
1546		hub->tt.think_time = 666 * 4;
1547		dev_dbg(hub_dev, "TT requires at most %d "
1548				"FS bit times (%d ns)\n",
1549			32, hub->tt.think_time);
1550		break;
1551	}
1552
1553	/* probe() zeroes hub->indicator[] */
1554	if (wHubCharacteristics & HUB_CHAR_PORTIND) {
1555		hub->has_indicators = 1;
1556		dev_dbg(hub_dev, "Port indicators are supported\n");
1557	}
1558
1559	dev_dbg(hub_dev, "power on to power good time: %dms\n",
1560		hub->descriptor->bPwrOn2PwrGood * 2);
1561
1562	/* power budgeting mostly matters with bus-powered hubs,
1563	 * and battery-powered root hubs (may provide just 8 mA).
1564	 */
1565	ret = usb_get_std_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
1566	if (ret) {
1567		message = "can't get hub status";
1568		goto fail;
1569	}
1570	hcd = bus_to_hcd(hdev->bus);
1571	if (hdev == hdev->bus->root_hub) {
1572		if (hcd->power_budget > 0)
1573			hdev->bus_mA = hcd->power_budget;
1574		else
1575			hdev->bus_mA = full_load * maxchild;
1576		if (hdev->bus_mA >= full_load)
1577			hub->mA_per_port = full_load;
1578		else {
1579			hub->mA_per_port = hdev->bus_mA;
1580			hub->limited_power = 1;
1581		}
1582	} else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1583		int remaining = hdev->bus_mA -
1584			hub->descriptor->bHubContrCurrent;
1585
1586		dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
1587			hub->descriptor->bHubContrCurrent);
1588		hub->limited_power = 1;
1589
1590		if (remaining < maxchild * unit_load)
1591			dev_warn(hub_dev,
1592					"insufficient power available "
1593					"to use all downstream ports\n");
1594		hub->mA_per_port = unit_load;	/* 7.2.1 */
1595
1596	} else {	/* Self-powered external hub */
1597		/* FIXME: What about battery-powered external hubs that
1598		 * provide less current per port? */
1599		hub->mA_per_port = full_load;
1600	}
1601	if (hub->mA_per_port < full_load)
1602		dev_dbg(hub_dev, "%umA bus power budget for each child\n",
1603				hub->mA_per_port);
1604
1605	ret = hub_hub_status(hub, &hubstatus, &hubchange);
1606	if (ret < 0) {
1607		message = "can't get hub status";
1608		goto fail;
1609	}
1610
1611	/* local power status reports aren't always correct */
1612	if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
1613		dev_dbg(hub_dev, "local power source is %s\n",
1614			(hubstatus & HUB_STATUS_LOCAL_POWER)
1615			? "lost (inactive)" : "good");
1616
1617	if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
1618		dev_dbg(hub_dev, "%sover-current condition exists\n",
1619			(hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
1620
1621	/* set up the interrupt endpoint
1622	 * We use the EP's maxpacket size instead of (PORTS+1+7)/8
1623	 * bytes as USB2.0[11.12.3] says because some hubs are known
1624	 * to send more data (and thus cause overflow). For root hubs,
1625	 * maxpktsize is defined in hcd.c's fake endpoint descriptors
1626	 * to be big enough for at least USB_MAXCHILDREN ports. */
1627	pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
1628	maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
1629
1630	if (maxp > sizeof(*hub->buffer))
1631		maxp = sizeof(*hub->buffer);
1632
1633	hub->urb = usb_alloc_urb(0, GFP_KERNEL);
1634	if (!hub->urb) {
1635		ret = -ENOMEM;
1636		goto fail;
1637	}
1638
1639	usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1640		hub, endpoint->bInterval);
1641
1642	/* maybe cycle the hub leds */
1643	if (hub->has_indicators && blinkenlights)
1644		hub->indicator[0] = INDICATOR_CYCLE;
1645
1646	mutex_lock(&usb_port_peer_mutex);
1647	for (i = 0; i < maxchild; i++) {
1648		ret = usb_hub_create_port_device(hub, i + 1);
1649		if (ret < 0) {
1650			dev_err(hub->intfdev,
1651				"couldn't create port%d device.\n", i + 1);
1652			break;
1653		}
1654	}
1655	hdev->maxchild = i;
1656	for (i = 0; i < hdev->maxchild; i++) {
1657		struct usb_port *port_dev = hub->ports[i];
1658
1659		pm_runtime_put(&port_dev->dev);
1660	}
1661
1662	mutex_unlock(&usb_port_peer_mutex);
1663	if (ret < 0)
1664		goto fail;
1665
1666	/* Update the HCD's internal representation of this hub before hub_wq
1667	 * starts getting port status changes for devices under the hub.
1668	 */
1669	if (hcd->driver->update_hub_device) {
1670		ret = hcd->driver->update_hub_device(hcd, hdev,
1671				&hub->tt, GFP_KERNEL);
1672		if (ret < 0) {
1673			message = "can't update HCD hub info";
1674			goto fail;
1675		}
1676	}
1677
1678	usb_hub_adjust_deviceremovable(hdev, hub->descriptor);
1679
1680	hub_activate(hub, HUB_INIT);
1681	return 0;
1682
1683fail:
1684	dev_err(hub_dev, "config failed, %s (err %d)\n",
1685			message, ret);
1686	/* hub_disconnect() frees urb and descriptor */
1687	return ret;
1688}
1689
1690static void hub_release(struct kref *kref)
1691{
1692	struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1693
1694	usb_put_dev(hub->hdev);
1695	usb_put_intf(to_usb_interface(hub->intfdev));
1696	kfree(hub);
1697}
1698
1699static unsigned highspeed_hubs;
1700
1701static void hub_disconnect(struct usb_interface *intf)
1702{
1703	struct usb_hub *hub = usb_get_intfdata(intf);
1704	struct usb_device *hdev = interface_to_usbdev(intf);
1705	int port1;
1706
1707	/*
1708	 * Stop adding new hub events. We do not want to block here and thus
1709	 * will not try to remove any pending work item.
1710	 */
1711	hub->disconnected = 1;
1712
1713	/* Disconnect all children and quiesce the hub */
1714	hub->error = 0;
1715	hub_quiesce(hub, HUB_DISCONNECT);
1716
1717	mutex_lock(&usb_port_peer_mutex);
1718
1719	/* Avoid races with recursively_mark_NOTATTACHED() */
1720	spin_lock_irq(&device_state_lock);
1721	port1 = hdev->maxchild;
1722	hdev->maxchild = 0;
1723	usb_set_intfdata(intf, NULL);
1724	spin_unlock_irq(&device_state_lock);
1725
1726	for (; port1 > 0; --port1)
1727		usb_hub_remove_port_device(hub, port1);
1728
1729	mutex_unlock(&usb_port_peer_mutex);
1730
1731	if (hub->hdev->speed == USB_SPEED_HIGH)
1732		highspeed_hubs--;
1733
1734	usb_free_urb(hub->urb);
1735	kfree(hub->ports);
1736	kfree(hub->descriptor);
1737	kfree(hub->status);
1738	kfree(hub->buffer);
1739
1740	pm_suspend_ignore_children(&intf->dev, false);
1741
1742	if (hub->quirk_disable_autosuspend)
1743		usb_autopm_put_interface(intf);
1744
1745	kref_put(&hub->kref, hub_release);
1746}
1747
1748static bool hub_descriptor_is_sane(struct usb_host_interface *desc)
1749{
1750	/* Some hubs have a subclass of 1, which AFAICT according to the */
1751	/*  specs is not defined, but it works */
1752	if (desc->desc.bInterfaceSubClass != 0 &&
1753	    desc->desc.bInterfaceSubClass != 1)
1754		return false;
1755
1756	/* Multiple endpoints? What kind of mutant ninja-hub is this? */
1757	if (desc->desc.bNumEndpoints != 1)
1758		return false;
1759
1760	/* If the first endpoint is not interrupt IN, we'd better punt! */
1761	if (!usb_endpoint_is_int_in(&desc->endpoint[0].desc))
1762		return false;
1763
1764        return true;
1765}
1766
1767static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1768{
1769	struct usb_host_interface *desc;
1770	struct usb_device *hdev;
1771	struct usb_hub *hub;
1772
1773	desc = intf->cur_altsetting;
1774	hdev = interface_to_usbdev(intf);
1775
1776	/*
1777	 * Set default autosuspend delay as 0 to speedup bus suspend,
1778	 * based on the below considerations:
1779	 *
1780	 * - Unlike other drivers, the hub driver does not rely on the
1781	 *   autosuspend delay to provide enough time to handle a wakeup
1782	 *   event, and the submitted status URB is just to check future
1783	 *   change on hub downstream ports, so it is safe to do it.
1784	 *
1785	 * - The patch might cause one or more auto supend/resume for
1786	 *   below very rare devices when they are plugged into hub
1787	 *   first time:
1788	 *
1789	 *   	devices having trouble initializing, and disconnect
1790	 *   	themselves from the bus and then reconnect a second
1791	 *   	or so later
1792	 *
1793	 *   	devices just for downloading firmware, and disconnects
1794	 *   	themselves after completing it
1795	 *
1796	 *   For these quite rare devices, their drivers may change the
1797	 *   autosuspend delay of their parent hub in the probe() to one
1798	 *   appropriate value to avoid the subtle problem if someone
1799	 *   does care it.
1800	 *
1801	 * - The patch may cause one or more auto suspend/resume on
1802	 *   hub during running 'lsusb', but it is probably too
1803	 *   infrequent to worry about.
1804	 *
1805	 * - Change autosuspend delay of hub can avoid unnecessary auto
1806	 *   suspend timer for hub, also may decrease power consumption
1807	 *   of USB bus.
1808	 *
1809	 * - If user has indicated to prevent autosuspend by passing
1810	 *   usbcore.autosuspend = -1 then keep autosuspend disabled.
1811	 */
1812#ifdef CONFIG_PM
1813	if (hdev->dev.power.autosuspend_delay >= 0)
1814		pm_runtime_set_autosuspend_delay(&hdev->dev, 0);
1815#endif
1816
1817	/*
1818	 * Hubs have proper suspend/resume support, except for root hubs
1819	 * where the controller driver doesn't have bus_suspend and
1820	 * bus_resume methods.
1821	 */
1822	if (hdev->parent) {		/* normal device */
1823		usb_enable_autosuspend(hdev);
1824	} else {			/* root hub */
1825		const struct hc_driver *drv = bus_to_hcd(hdev->bus)->driver;
1826
1827		if (drv->bus_suspend && drv->bus_resume)
1828			usb_enable_autosuspend(hdev);
1829	}
1830
1831	if (hdev->level == MAX_TOPO_LEVEL) {
1832		dev_err(&intf->dev,
1833			"Unsupported bus topology: hub nested too deep\n");
1834		return -E2BIG;
1835	}
1836
1837#ifdef	CONFIG_USB_OTG_DISABLE_EXTERNAL_HUB
1838	if (hdev->parent) {
1839		dev_warn(&intf->dev, "ignoring external hub\n");
1840		return -ENODEV;
1841	}
1842#endif
1843
1844	if (!hub_descriptor_is_sane(desc)) {
1845		dev_err(&intf->dev, "bad descriptor, ignoring hub\n");
1846		return -EIO;
1847	}
1848
1849	/* We found a hub */
1850	dev_info(&intf->dev, "USB hub found\n");
1851
1852	hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1853	if (!hub)
1854		return -ENOMEM;
1855
1856	kref_init(&hub->kref);
1857	hub->intfdev = &intf->dev;
1858	hub->hdev = hdev;
1859	INIT_DELAYED_WORK(&hub->leds, led_work);
1860	INIT_DELAYED_WORK(&hub->init_work, NULL);
1861	INIT_WORK(&hub->events, hub_event);
1862	spin_lock_init(&hub->irq_urb_lock);
1863	timer_setup(&hub->irq_urb_retry, hub_retry_irq_urb, 0);
1864	usb_get_intf(intf);
1865	usb_get_dev(hdev);
1866
1867	usb_set_intfdata(intf, hub);
1868	intf->needs_remote_wakeup = 1;
1869	pm_suspend_ignore_children(&intf->dev, true);
1870
1871	if (hdev->speed == USB_SPEED_HIGH)
1872		highspeed_hubs++;
1873
1874	if (id->driver_info & HUB_QUIRK_CHECK_PORT_AUTOSUSPEND)
1875		hub->quirk_check_port_auto_suspend = 1;
1876
1877	if (id->driver_info & HUB_QUIRK_DISABLE_AUTOSUSPEND) {
1878		hub->quirk_disable_autosuspend = 1;
1879		usb_autopm_get_interface_no_resume(intf);
1880	}
1881
1882	if (hub_configure(hub, &desc->endpoint[0].desc) >= 0)
1883		return 0;
1884
1885	hub_disconnect(intf);
1886	return -ENODEV;
1887}
1888
1889static int
1890hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1891{
1892	struct usb_device *hdev = interface_to_usbdev(intf);
1893	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
1894
1895	/* assert ifno == 0 (part of hub spec) */
1896	switch (code) {
1897	case USBDEVFS_HUB_PORTINFO: {
1898		struct usbdevfs_hub_portinfo *info = user_data;
1899		int i;
1900
1901		spin_lock_irq(&device_state_lock);
1902		if (hdev->devnum <= 0)
1903			info->nports = 0;
1904		else {
1905			info->nports = hdev->maxchild;
1906			for (i = 0; i < info->nports; i++) {
1907				if (hub->ports[i]->child == NULL)
1908					info->port[i] = 0;
1909				else
1910					info->port[i] =
1911						hub->ports[i]->child->devnum;
1912			}
1913		}
1914		spin_unlock_irq(&device_state_lock);
1915
1916		return info->nports + 1;
1917		}
1918
1919	default:
1920		return -ENOSYS;
1921	}
1922}
1923
1924/*
1925 * Allow user programs to claim ports on a hub.  When a device is attached
1926 * to one of these "claimed" ports, the program will "own" the device.
1927 */
1928static int find_port_owner(struct usb_device *hdev, unsigned port1,
1929		struct usb_dev_state ***ppowner)
1930{
1931	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
1932
1933	if (hdev->state == USB_STATE_NOTATTACHED)
1934		return -ENODEV;
1935	if (port1 == 0 || port1 > hdev->maxchild)
1936		return -EINVAL;
1937
1938	/* Devices not managed by the hub driver
1939	 * will always have maxchild equal to 0.
1940	 */
1941	*ppowner = &(hub->ports[port1 - 1]->port_owner);
1942	return 0;
1943}
1944
1945/* In the following three functions, the caller must hold hdev's lock */
1946int usb_hub_claim_port(struct usb_device *hdev, unsigned port1,
1947		       struct usb_dev_state *owner)
1948{
1949	int rc;
1950	struct usb_dev_state **powner;
1951
1952	rc = find_port_owner(hdev, port1, &powner);
1953	if (rc)
1954		return rc;
1955	if (*powner)
1956		return -EBUSY;
1957	*powner = owner;
1958	return rc;
1959}
1960EXPORT_SYMBOL_GPL(usb_hub_claim_port);
1961
1962int usb_hub_release_port(struct usb_device *hdev, unsigned port1,
1963			 struct usb_dev_state *owner)
1964{
1965	int rc;
1966	struct usb_dev_state **powner;
1967
1968	rc = find_port_owner(hdev, port1, &powner);
1969	if (rc)
1970		return rc;
1971	if (*powner != owner)
1972		return -ENOENT;
1973	*powner = NULL;
1974	return rc;
1975}
1976EXPORT_SYMBOL_GPL(usb_hub_release_port);
1977
1978void usb_hub_release_all_ports(struct usb_device *hdev, struct usb_dev_state *owner)
1979{
1980	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
1981	int n;
1982
1983	for (n = 0; n < hdev->maxchild; n++) {
1984		if (hub->ports[n]->port_owner == owner)
1985			hub->ports[n]->port_owner = NULL;
1986	}
1987
1988}
1989
1990/* The caller must hold udev's lock */
1991bool usb_device_is_owned(struct usb_device *udev)
1992{
1993	struct usb_hub *hub;
1994
1995	if (udev->state == USB_STATE_NOTATTACHED || !udev->parent)
1996		return false;
1997	hub = usb_hub_to_struct_hub(udev->parent);
1998	return !!hub->ports[udev->portnum - 1]->port_owner;
1999}
2000
2001static void recursively_mark_NOTATTACHED(struct usb_device *udev)
2002{
2003	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
2004	int i;
2005
2006	for (i = 0; i < udev->maxchild; ++i) {
2007		if (hub->ports[i]->child)
2008			recursively_mark_NOTATTACHED(hub->ports[i]->child);
2009	}
2010	if (udev->state == USB_STATE_SUSPENDED)
2011		udev->active_duration -= jiffies;
2012	udev->state = USB_STATE_NOTATTACHED;
2013}
2014
2015/**
2016 * usb_set_device_state - change a device's current state (usbcore, hcds)
2017 * @udev: pointer to device whose state should be changed
2018 * @new_state: new state value to be stored
2019 *
2020 * udev->state is _not_ fully protected by the device lock.  Although
2021 * most transitions are made only while holding the lock, the state can
2022 * can change to USB_STATE_NOTATTACHED at almost any time.  This
2023 * is so that devices can be marked as disconnected as soon as possible,
2024 * without having to wait for any semaphores to be released.  As a result,
2025 * all changes to any device's state must be protected by the
2026 * device_state_lock spinlock.
2027 *
2028 * Once a device has been added to the device tree, all changes to its state
2029 * should be made using this routine.  The state should _not_ be set directly.
2030 *
2031 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
2032 * Otherwise udev->state is set to new_state, and if new_state is
2033 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
2034 * to USB_STATE_NOTATTACHED.
2035 */
2036void usb_set_device_state(struct usb_device *udev,
2037		enum usb_device_state new_state)
2038{
2039	unsigned long flags;
2040	int wakeup = -1;
2041
2042	spin_lock_irqsave(&device_state_lock, flags);
2043	if (udev->state == USB_STATE_NOTATTACHED)
2044		;	/* do nothing */
2045	else if (new_state != USB_STATE_NOTATTACHED) {
2046
2047		/* root hub wakeup capabilities are managed out-of-band
2048		 * and may involve silicon errata ... ignore them here.
2049		 */
2050		if (udev->parent) {
2051			if (udev->state == USB_STATE_SUSPENDED
2052					|| new_state == USB_STATE_SUSPENDED)
2053				;	/* No change to wakeup settings */
2054			else if (new_state == USB_STATE_CONFIGURED)
2055				wakeup = (udev->quirks &
2056					USB_QUIRK_IGNORE_REMOTE_WAKEUP) ? 0 :
2057					udev->actconfig->desc.bmAttributes &
2058					USB_CONFIG_ATT_WAKEUP;
2059			else
2060				wakeup = 0;
2061		}
2062		if (udev->state == USB_STATE_SUSPENDED &&
2063			new_state != USB_STATE_SUSPENDED)
2064			udev->active_duration -= jiffies;
2065		else if (new_state == USB_STATE_SUSPENDED &&
2066				udev->state != USB_STATE_SUSPENDED)
2067			udev->active_duration += jiffies;
2068		udev->state = new_state;
2069	} else
2070		recursively_mark_NOTATTACHED(udev);
2071	spin_unlock_irqrestore(&device_state_lock, flags);
2072	if (wakeup >= 0)
2073		device_set_wakeup_capable(&udev->dev, wakeup);
2074}
2075EXPORT_SYMBOL_GPL(usb_set_device_state);
2076
2077/*
2078 * Choose a device number.
2079 *
2080 * Device numbers are used as filenames in usbfs.  On USB-1.1 and
2081 * USB-2.0 buses they are also used as device addresses, however on
2082 * USB-3.0 buses the address is assigned by the controller hardware
2083 * and it usually is not the same as the device number.
2084 *
2085 * WUSB devices are simple: they have no hubs behind, so the mapping
2086 * device <-> virtual port number becomes 1:1. Why? to simplify the
2087 * life of the device connection logic in
2088 * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
2089 * handshake we need to assign a temporary address in the unauthorized
2090 * space. For simplicity we use the first virtual port number found to
2091 * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
2092 * and that becomes it's address [X < 128] or its unauthorized address
2093 * [X | 0x80].
2094 *
2095 * We add 1 as an offset to the one-based USB-stack port number
2096 * (zero-based wusb virtual port index) for two reasons: (a) dev addr
2097 * 0 is reserved by USB for default address; (b) Linux's USB stack
2098 * uses always #1 for the root hub of the controller. So USB stack's
2099 * port #1, which is wusb virtual-port #0 has address #2.
2100 *
2101 * Devices connected under xHCI are not as simple.  The host controller
2102 * supports virtualization, so the hardware assigns device addresses and
2103 * the HCD must setup data structures before issuing a set address
2104 * command to the hardware.
2105 */
2106static void choose_devnum(struct usb_device *udev)
2107{
2108	int		devnum;
2109	struct usb_bus	*bus = udev->bus;
2110
2111	/* be safe when more hub events are proceed in parallel */
2112	mutex_lock(&bus->devnum_next_mutex);
2113	if (udev->wusb) {
2114		devnum = udev->portnum + 1;
2115		BUG_ON(test_bit(devnum, bus->devmap.devicemap));
2116	} else {
2117		/* Try to allocate the next devnum beginning at
2118		 * bus->devnum_next. */
2119		devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
2120					    bus->devnum_next);
2121		if (devnum >= 128)
2122			devnum = find_next_zero_bit(bus->devmap.devicemap,
2123						    128, 1);
2124		bus->devnum_next = (devnum >= 127 ? 1 : devnum + 1);
2125	}
2126	if (devnum < 128) {
2127		set_bit(devnum, bus->devmap.devicemap);
2128		udev->devnum = devnum;
2129	}
2130	mutex_unlock(&bus->devnum_next_mutex);
2131}
2132
2133static void release_devnum(struct usb_device *udev)
2134{
2135	if (udev->devnum > 0) {
2136		clear_bit(udev->devnum, udev->bus->devmap.devicemap);
2137		udev->devnum = -1;
2138	}
2139}
2140
2141static void update_devnum(struct usb_device *udev, int devnum)
2142{
2143	/* The address for a WUSB device is managed by wusbcore. */
2144	if (!udev->wusb)
2145		udev->devnum = devnum;
2146	if (!udev->devaddr)
2147		udev->devaddr = (u8)devnum;
2148}
2149
2150static void hub_free_dev(struct usb_device *udev)
2151{
2152	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2153
2154	/* Root hubs aren't real devices, so don't free HCD resources */
2155	if (hcd->driver->free_dev && udev->parent)
2156		hcd->driver->free_dev(hcd, udev);
2157}
2158
2159static void hub_disconnect_children(struct usb_device *udev)
2160{
2161	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
2162	int i;
2163
2164	/* Free up all the children before we remove this device */
2165	for (i = 0; i < udev->maxchild; i++) {
2166		if (hub->ports[i]->child)
2167			usb_disconnect(&hub->ports[i]->child);
2168	}
2169}
2170
2171/**
2172 * usb_disconnect - disconnect a device (usbcore-internal)
2173 * @pdev: pointer to device being disconnected
2174 * Context: !in_interrupt ()
2175 *
2176 * Something got disconnected. Get rid of it and all of its children.
2177 *
2178 * If *pdev is a normal device then the parent hub must already be locked.
2179 * If *pdev is a root hub then the caller must hold the usb_bus_idr_lock,
2180 * which protects the set of root hubs as well as the list of buses.
2181 *
2182 * Only hub drivers (including virtual root hub drivers for host
2183 * controllers) should ever call this.
2184 *
2185 * This call is synchronous, and may not be used in an interrupt context.
2186 */
2187void usb_disconnect(struct usb_device **pdev)
2188{
2189	struct usb_port *port_dev = NULL;
2190	struct usb_device *udev = *pdev;
2191	struct usb_hub *hub = NULL;
2192	int port1 = 1;
2193
2194	/* mark the device as inactive, so any further urb submissions for
2195	 * this device (and any of its children) will fail immediately.
2196	 * this quiesces everything except pending urbs.
2197	 */
2198	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2199	dev_info(&udev->dev, "USB disconnect, device number %d\n",
2200			udev->devnum);
2201
2202	/*
2203	 * Ensure that the pm runtime code knows that the USB device
2204	 * is in the process of being disconnected.
2205	 */
2206	pm_runtime_barrier(&udev->dev);
2207
2208	usb_lock_device(udev);
2209
2210	hub_disconnect_children(udev);
2211
2212	/* deallocate hcd/hardware state ... nuking all pending urbs and
2213	 * cleaning up all state associated with the current configuration
2214	 * so that the hardware is now fully quiesced.
2215	 */
2216	dev_dbg(&udev->dev, "unregistering device\n");
2217	usb_disable_device(udev, 0);
2218	usb_hcd_synchronize_unlinks(udev);
2219
2220	if (udev->parent) {
2221		port1 = udev->portnum;
2222		hub = usb_hub_to_struct_hub(udev->parent);
2223		port_dev = hub->ports[port1 - 1];
2224
2225		sysfs_remove_link(&udev->dev.kobj, "port");
2226		sysfs_remove_link(&port_dev->dev.kobj, "device");
2227
2228		/*
2229		 * As usb_port_runtime_resume() de-references udev, make
2230		 * sure no resumes occur during removal
2231		 */
2232		if (!test_and_set_bit(port1, hub->child_usage_bits))
2233			pm_runtime_get_sync(&port_dev->dev);
2234	}
2235
2236	usb_remove_ep_devs(&udev->ep0);
2237	usb_unlock_device(udev);
2238
2239	/* Unregister the device.  The device driver is responsible
2240	 * for de-configuring the device and invoking the remove-device
2241	 * notifier chain (used by usbfs and possibly others).
2242	 */
2243	device_del(&udev->dev);
2244
2245	/* Free the device number and delete the parent's children[]
2246	 * (or root_hub) pointer.
2247	 */
2248	release_devnum(udev);
2249
2250	/* Avoid races with recursively_mark_NOTATTACHED() */
2251	spin_lock_irq(&device_state_lock);
2252	*pdev = NULL;
2253	spin_unlock_irq(&device_state_lock);
2254
2255	if (port_dev && test_and_clear_bit(port1, hub->child_usage_bits))
2256		pm_runtime_put(&port_dev->dev);
2257
2258	hub_free_dev(udev);
2259
2260	put_device(&udev->dev);
2261}
2262
2263#ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
2264static void show_string(struct usb_device *udev, char *id, char *string)
2265{
2266	if (!string)
2267		return;
2268	dev_info(&udev->dev, "%s: %s\n", id, string);
2269}
2270
2271static void announce_device(struct usb_device *udev)
2272{
2273	u16 bcdDevice = le16_to_cpu(udev->descriptor.bcdDevice);
2274
2275	dev_info(&udev->dev,
2276		"New USB device found, idVendor=%04x, idProduct=%04x, bcdDevice=%2x.%02x\n",
2277		le16_to_cpu(udev->descriptor.idVendor),
2278		le16_to_cpu(udev->descriptor.idProduct),
2279		bcdDevice >> 8, bcdDevice & 0xff);
2280	dev_info(&udev->dev,
2281		"New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
2282		udev->descriptor.iManufacturer,
2283		udev->descriptor.iProduct,
2284		udev->descriptor.iSerialNumber);
2285	show_string(udev, "Product", udev->product);
2286	show_string(udev, "Manufacturer", udev->manufacturer);
2287	show_string(udev, "SerialNumber", udev->serial);
2288}
2289#else
2290static inline void announce_device(struct usb_device *udev) { }
2291#endif
2292
2293
2294/**
2295 * usb_enumerate_device_otg - FIXME (usbcore-internal)
2296 * @udev: newly addressed device (in ADDRESS state)
2297 *
2298 * Finish enumeration for On-The-Go devices
2299 *
2300 * Return: 0 if successful. A negative error code otherwise.
2301 */
2302static int usb_enumerate_device_otg(struct usb_device *udev)
2303{
2304	int err = 0;
2305
2306#ifdef	CONFIG_USB_OTG
2307	/*
2308	 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
2309	 * to wake us after we've powered off VBUS; and HNP, switching roles
2310	 * "host" to "peripheral".  The OTG descriptor helps figure this out.
2311	 */
2312	if (!udev->bus->is_b_host
2313			&& udev->config
2314			&& udev->parent == udev->bus->root_hub) {
2315		struct usb_otg_descriptor	*desc = NULL;
2316		struct usb_bus			*bus = udev->bus;
2317		unsigned			port1 = udev->portnum;
2318
2319		/* descriptor may appear anywhere in config */
2320		err = __usb_get_extra_descriptor(udev->rawdescriptors[0],
2321				le16_to_cpu(udev->config[0].desc.wTotalLength),
2322				USB_DT_OTG, (void **) &desc, sizeof(*desc));
2323		if (err || !(desc->bmAttributes & USB_OTG_HNP))
2324			return 0;
2325
2326		dev_info(&udev->dev, "Dual-Role OTG device on %sHNP port\n",
2327					(port1 == bus->otg_port) ? "" : "non-");
2328
2329		/* enable HNP before suspend, it's simpler */
2330		if (port1 == bus->otg_port) {
2331			bus->b_hnp_enable = 1;
2332			err = usb_control_msg(udev,
2333				usb_sndctrlpipe(udev, 0),
2334				USB_REQ_SET_FEATURE, 0,
2335				USB_DEVICE_B_HNP_ENABLE,
2336				0, NULL, 0,
2337				USB_CTRL_SET_TIMEOUT);
2338			if (err < 0) {
2339				/*
2340				 * OTG MESSAGE: report errors here,
2341				 * customize to match your product.
2342				 */
2343				dev_err(&udev->dev, "can't set HNP mode: %d\n",
2344									err);
2345				bus->b_hnp_enable = 0;
2346			}
2347		} else if (desc->bLength == sizeof
2348				(struct usb_otg_descriptor)) {
2349			/* Set a_alt_hnp_support for legacy otg device */
2350			err = usb_control_msg(udev,
2351				usb_sndctrlpipe(udev, 0),
2352				USB_REQ_SET_FEATURE, 0,
2353				USB_DEVICE_A_ALT_HNP_SUPPORT,
2354				0, NULL, 0,
2355				USB_CTRL_SET_TIMEOUT);
2356			if (err < 0)
2357				dev_err(&udev->dev,
2358					"set a_alt_hnp_support failed: %d\n",
2359					err);
2360		}
2361	}
2362#endif
2363	return err;
2364}
2365
2366
2367/**
2368 * usb_enumerate_device - Read device configs/intfs/otg (usbcore-internal)
2369 * @udev: newly addressed device (in ADDRESS state)
2370 *
2371 * This is only called by usb_new_device() and usb_authorize_device()
2372 * and FIXME -- all comments that apply to them apply here wrt to
2373 * environment.
2374 *
2375 * If the device is WUSB and not authorized, we don't attempt to read
2376 * the string descriptors, as they will be errored out by the device
2377 * until it has been authorized.
2378 *
2379 * Return: 0 if successful. A negative error code otherwise.
2380 */
2381static int usb_enumerate_device(struct usb_device *udev)
2382{
2383	int err;
2384	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2385
2386	if (udev->config == NULL) {
2387		err = usb_get_configuration(udev);
2388		if (err < 0) {
2389			if (err != -ENODEV)
2390				dev_err(&udev->dev, "can't read configurations, error %d\n",
2391						err);
2392			return err;
2393		}
2394	}
2395
2396	/* read the standard strings and cache them if present */
2397	udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
2398	udev->manufacturer = usb_cache_string(udev,
2399					      udev->descriptor.iManufacturer);
2400	udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
2401
2402	err = usb_enumerate_device_otg(udev);
2403	if (err < 0)
2404		return err;
2405
2406	if (IS_ENABLED(CONFIG_USB_OTG_PRODUCTLIST) && hcd->tpl_support &&
2407		!is_targeted(udev)) {
2408		/* Maybe it can talk to us, though we can't talk to it.
2409		 * (Includes HNP test device.)
2410		 */
2411		if (IS_ENABLED(CONFIG_USB_OTG) && (udev->bus->b_hnp_enable
2412			|| udev->bus->is_b_host)) {
2413			err = usb_port_suspend(udev, PMSG_AUTO_SUSPEND);
2414			if (err < 0)
2415				dev_dbg(&udev->dev, "HNP fail, %d\n", err);
2416		}
2417		return -ENOTSUPP;
2418	}
2419
2420	usb_detect_interface_quirks(udev);
2421
2422	return 0;
2423}
2424
2425static void set_usb_port_removable(struct usb_device *udev)
2426{
2427	struct usb_device *hdev = udev->parent;
2428	struct usb_hub *hub;
2429	u8 port = udev->portnum;
2430	u16 wHubCharacteristics;
2431	bool removable = true;
2432
2433	if (!hdev)
2434		return;
2435
2436	hub = usb_hub_to_struct_hub(udev->parent);
2437
2438	/*
2439	 * If the platform firmware has provided information about a port,
2440	 * use that to determine whether it's removable.
2441	 */
2442	switch (hub->ports[udev->portnum - 1]->connect_type) {
2443	case USB_PORT_CONNECT_TYPE_HOT_PLUG:
2444		udev->removable = USB_DEVICE_REMOVABLE;
2445		return;
2446	case USB_PORT_CONNECT_TYPE_HARD_WIRED:
2447	case USB_PORT_NOT_USED:
2448		udev->removable = USB_DEVICE_FIXED;
2449		return;
2450	default:
2451		break;
2452	}
2453
2454	/*
2455	 * Otherwise, check whether the hub knows whether a port is removable
2456	 * or not
2457	 */
2458	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2459
2460	if (!(wHubCharacteristics & HUB_CHAR_COMPOUND))
2461		return;
2462
2463	if (hub_is_superspeed(hdev)) {
2464		if (le16_to_cpu(hub->descriptor->u.ss.DeviceRemovable)
2465				& (1 << port))
2466			removable = false;
2467	} else {
2468		if (hub->descriptor->u.hs.DeviceRemovable[port / 8] & (1 << (port % 8)))
2469			removable = false;
2470	}
2471
2472	if (removable)
2473		udev->removable = USB_DEVICE_REMOVABLE;
2474	else
2475		udev->removable = USB_DEVICE_FIXED;
2476
2477}
2478
2479/**
2480 * usb_new_device - perform initial device setup (usbcore-internal)
2481 * @udev: newly addressed device (in ADDRESS state)
2482 *
2483 * This is called with devices which have been detected but not fully
2484 * enumerated.  The device descriptor is available, but not descriptors
2485 * for any device configuration.  The caller must have locked either
2486 * the parent hub (if udev is a normal device) or else the
2487 * usb_bus_idr_lock (if udev is a root hub).  The parent's pointer to
2488 * udev has already been installed, but udev is not yet visible through
2489 * sysfs or other filesystem code.
2490 *
2491 * This call is synchronous, and may not be used in an interrupt context.
2492 *
2493 * Only the hub driver or root-hub registrar should ever call this.
2494 *
2495 * Return: Whether the device is configured properly or not. Zero if the
2496 * interface was registered with the driver core; else a negative errno
2497 * value.
2498 *
2499 */
2500int usb_new_device(struct usb_device *udev)
2501{
2502	int err;
2503
2504	if (udev->parent) {
2505		/* Initialize non-root-hub device wakeup to disabled;
2506		 * device (un)configuration controls wakeup capable
2507		 * sysfs power/wakeup controls wakeup enabled/disabled
2508		 */
2509		device_init_wakeup(&udev->dev, 0);
2510	}
2511
2512	/* Tell the runtime-PM framework the device is active */
2513	pm_runtime_set_active(&udev->dev);
2514	pm_runtime_get_noresume(&udev->dev);
2515	pm_runtime_use_autosuspend(&udev->dev);
2516	pm_runtime_enable(&udev->dev);
2517
2518	/* By default, forbid autosuspend for all devices.  It will be
2519	 * allowed for hubs during binding.
2520	 */
2521	usb_disable_autosuspend(udev);
2522
2523	err = usb_enumerate_device(udev);	/* Read descriptors */
2524	if (err < 0)
2525		goto fail;
2526	dev_dbg(&udev->dev, "udev %d, busnum %d, minor = %d\n",
2527			udev->devnum, udev->bus->busnum,
2528			(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2529	/* export the usbdev device-node for libusb */
2530	udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
2531			(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2532
2533	/* Tell the world! */
2534	announce_device(udev);
2535
2536	if (udev->serial)
2537		add_device_randomness(udev->serial, strlen(udev->serial));
2538	if (udev->product)
2539		add_device_randomness(udev->product, strlen(udev->product));
2540	if (udev->manufacturer)
2541		add_device_randomness(udev->manufacturer,
2542				      strlen(udev->manufacturer));
2543
2544	device_enable_async_suspend(&udev->dev);
2545
2546	/* check whether the hub or firmware marks this port as non-removable */
2547	if (udev->parent)
2548		set_usb_port_removable(udev);
2549
2550	/* Register the device.  The device driver is responsible
2551	 * for configuring the device and invoking the add-device
2552	 * notifier chain (used by usbfs and possibly others).
2553	 */
2554	err = device_add(&udev->dev);
2555	if (err) {
2556		dev_err(&udev->dev, "can't device_add, error %d\n", err);
2557		goto fail;
2558	}
2559
2560	/* Create link files between child device and usb port device. */
2561	if (udev->parent) {
2562		struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
2563		int port1 = udev->portnum;
2564		struct usb_port	*port_dev = hub->ports[port1 - 1];
2565
2566		err = sysfs_create_link(&udev->dev.kobj,
2567				&port_dev->dev.kobj, "port");
2568		if (err)
2569			goto fail;
2570
2571		err = sysfs_create_link(&port_dev->dev.kobj,
2572				&udev->dev.kobj, "device");
2573		if (err) {
2574			sysfs_remove_link(&udev->dev.kobj, "port");
2575			goto fail;
2576		}
2577
2578		if (!test_and_set_bit(port1, hub->child_usage_bits))
2579			pm_runtime_get_sync(&port_dev->dev);
2580	}
2581
2582	(void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev);
2583	usb_mark_last_busy(udev);
2584	pm_runtime_put_sync_autosuspend(&udev->dev);
2585	return err;
2586
2587fail:
2588	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2589	pm_runtime_disable(&udev->dev);
2590	pm_runtime_set_suspended(&udev->dev);
2591	return err;
2592}
2593
2594
2595/**
2596 * usb_deauthorize_device - deauthorize a device (usbcore-internal)
2597 * @usb_dev: USB device
2598 *
2599 * Move the USB device to a very basic state where interfaces are disabled
2600 * and the device is in fact unconfigured and unusable.
2601 *
2602 * We share a lock (that we have) with device_del(), so we need to
2603 * defer its call.
2604 *
2605 * Return: 0.
2606 */
2607int usb_deauthorize_device(struct usb_device *usb_dev)
2608{
2609	usb_lock_device(usb_dev);
2610	if (usb_dev->authorized == 0)
2611		goto out_unauthorized;
2612
2613	usb_dev->authorized = 0;
2614	usb_set_configuration(usb_dev, -1);
2615
2616out_unauthorized:
2617	usb_unlock_device(usb_dev);
2618	return 0;
2619}
2620
2621
2622int usb_authorize_device(struct usb_device *usb_dev)
2623{
2624	int result = 0, c;
2625
2626	usb_lock_device(usb_dev);
2627	if (usb_dev->authorized == 1)
2628		goto out_authorized;
2629
2630	result = usb_autoresume_device(usb_dev);
2631	if (result < 0) {
2632		dev_err(&usb_dev->dev,
2633			"can't autoresume for authorization: %d\n", result);
2634		goto error_autoresume;
2635	}
2636
2637	if (usb_dev->wusb) {
2638		result = usb_get_device_descriptor(usb_dev, sizeof(usb_dev->descriptor));
2639		if (result < 0) {
2640			dev_err(&usb_dev->dev, "can't re-read device descriptor for "
2641				"authorization: %d\n", result);
2642			goto error_device_descriptor;
2643		}
2644	}
2645
2646	usb_dev->authorized = 1;
2647	/* Choose and set the configuration.  This registers the interfaces
2648	 * with the driver core and lets interface drivers bind to them.
2649	 */
2650	c = usb_choose_configuration(usb_dev);
2651	if (c >= 0) {
2652		result = usb_set_configuration(usb_dev, c);
2653		if (result) {
2654			dev_err(&usb_dev->dev,
2655				"can't set config #%d, error %d\n", c, result);
2656			/* This need not be fatal.  The user can try to
2657			 * set other configurations. */
2658		}
2659	}
2660	dev_info(&usb_dev->dev, "authorized to connect\n");
2661
2662error_device_descriptor:
2663	usb_autosuspend_device(usb_dev);
2664error_autoresume:
2665out_authorized:
2666	usb_unlock_device(usb_dev);	/* complements locktree */
2667	return result;
2668}
2669
2670/*
2671 * Return 1 if port speed is SuperSpeedPlus, 0 otherwise
2672 * check it from the link protocol field of the current speed ID attribute.
2673 * current speed ID is got from ext port status request. Sublink speed attribute
2674 * table is returned with the hub BOS SSP device capability descriptor
2675 */
2676static int port_speed_is_ssp(struct usb_device *hdev, int speed_id)
2677{
2678	int ssa_count;
2679	u32 ss_attr;
2680	int i;
2681	struct usb_ssp_cap_descriptor *ssp_cap = hdev->bos->ssp_cap;
2682
2683	if (!ssp_cap)
2684		return 0;
2685
2686	ssa_count = le32_to_cpu(ssp_cap->bmAttributes) &
2687		USB_SSP_SUBLINK_SPEED_ATTRIBS;
2688
2689	for (i = 0; i <= ssa_count; i++) {
2690		ss_attr = le32_to_cpu(ssp_cap->bmSublinkSpeedAttr[i]);
2691		if (speed_id == (ss_attr & USB_SSP_SUBLINK_SPEED_SSID))
2692			return !!(ss_attr & USB_SSP_SUBLINK_SPEED_LP);
2693	}
2694	return 0;
2695}
2696
2697/* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
2698static unsigned hub_is_wusb(struct usb_hub *hub)
2699{
2700	struct usb_hcd *hcd;
2701	if (hub->hdev->parent != NULL)  /* not a root hub? */
2702		return 0;
2703	hcd = bus_to_hcd(hub->hdev->bus);
2704	return hcd->wireless;
2705}
2706
2707
2708#define PORT_RESET_TRIES	5
2709#define SET_ADDRESS_TRIES	2
2710#define GET_DESCRIPTOR_TRIES	2
2711#define SET_CONFIG_TRIES	(2 * (use_both_schemes + 1))
2712#define USE_NEW_SCHEME(i, scheme)	((i) / 2 == (int)(scheme))
2713
2714#define HUB_ROOT_RESET_TIME	60	/* times are in msec */
2715#define HUB_SHORT_RESET_TIME	10
2716#define HUB_BH_RESET_TIME	50
2717#define HUB_LONG_RESET_TIME	200
2718#define HUB_RESET_TIMEOUT	800
2719
2720/*
2721 * "New scheme" enumeration causes an extra state transition to be
2722 * exposed to an xhci host and causes USB3 devices to receive control
2723 * commands in the default state.  This has been seen to cause
2724 * enumeration failures, so disable this enumeration scheme for USB3
2725 * devices.
2726 */
2727static bool use_new_scheme(struct usb_device *udev, int retry,
2728			   struct usb_port *port_dev)
2729{
2730	int old_scheme_first_port =
2731		port_dev->quirks & USB_PORT_QUIRK_OLD_SCHEME;
 
2732
2733	if (udev->speed >= USB_SPEED_SUPER)
2734		return false;
2735
2736	return USE_NEW_SCHEME(retry, old_scheme_first_port || old_scheme_first);
 
2737}
2738
2739/* Is a USB 3.0 port in the Inactive or Compliance Mode state?
2740 * Port warm reset is required to recover
2741 */
2742static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
2743		u16 portstatus)
2744{
2745	u16 link_state;
2746
2747	if (!hub_is_superspeed(hub->hdev))
2748		return false;
2749
2750	if (test_bit(port1, hub->warm_reset_bits))
2751		return true;
2752
2753	link_state = portstatus & USB_PORT_STAT_LINK_STATE;
2754	return link_state == USB_SS_PORT_LS_SS_INACTIVE
2755		|| link_state == USB_SS_PORT_LS_COMP_MOD;
2756}
2757
2758static int hub_port_wait_reset(struct usb_hub *hub, int port1,
2759			struct usb_device *udev, unsigned int delay, bool warm)
2760{
2761	int delay_time, ret;
2762	u16 portstatus;
2763	u16 portchange;
2764	u32 ext_portstatus = 0;
2765
2766	for (delay_time = 0;
2767			delay_time < HUB_RESET_TIMEOUT;
2768			delay_time += delay) {
2769		/* wait to give the device a chance to reset */
2770		msleep(delay);
2771
2772		/* read and decode port status */
2773		if (hub_is_superspeedplus(hub->hdev))
2774			ret = hub_ext_port_status(hub, port1,
2775						  HUB_EXT_PORT_STATUS,
2776						  &portstatus, &portchange,
2777						  &ext_portstatus);
2778		else
2779			ret = hub_port_status(hub, port1, &portstatus,
2780					      &portchange);
2781		if (ret < 0)
2782			return ret;
2783
2784		/*
2785		 * The port state is unknown until the reset completes.
2786		 *
2787		 * On top of that, some chips may require additional time
2788		 * to re-establish a connection after the reset is complete,
2789		 * so also wait for the connection to be re-established.
2790		 */
2791		if (!(portstatus & USB_PORT_STAT_RESET) &&
2792		    (portstatus & USB_PORT_STAT_CONNECTION))
2793			break;
2794
2795		/* switch to the long delay after two short delay failures */
2796		if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
2797			delay = HUB_LONG_RESET_TIME;
2798
2799		dev_dbg(&hub->ports[port1 - 1]->dev,
2800				"not %sreset yet, waiting %dms\n",
2801				warm ? "warm " : "", delay);
2802	}
2803
2804	if ((portstatus & USB_PORT_STAT_RESET))
2805		return -EBUSY;
2806
2807	if (hub_port_warm_reset_required(hub, port1, portstatus))
2808		return -ENOTCONN;
2809
2810	/* Device went away? */
2811	if (!(portstatus & USB_PORT_STAT_CONNECTION))
2812		return -ENOTCONN;
2813
2814	/* Retry if connect change is set but status is still connected.
2815	 * A USB 3.0 connection may bounce if multiple warm resets were issued,
2816	 * but the device may have successfully re-connected. Ignore it.
2817	 */
2818	if (!hub_is_superspeed(hub->hdev) &&
2819	    (portchange & USB_PORT_STAT_C_CONNECTION)) {
2820		usb_clear_port_feature(hub->hdev, port1,
2821				       USB_PORT_FEAT_C_CONNECTION);
2822		return -EAGAIN;
2823	}
2824
2825	if (!(portstatus & USB_PORT_STAT_ENABLE))
2826		return -EBUSY;
2827
2828	if (!udev)
2829		return 0;
2830
2831	if (hub_is_superspeedplus(hub->hdev)) {
2832		/* extended portstatus Rx and Tx lane count are zero based */
2833		udev->rx_lanes = USB_EXT_PORT_RX_LANES(ext_portstatus) + 1;
2834		udev->tx_lanes = USB_EXT_PORT_TX_LANES(ext_portstatus) + 1;
2835	} else {
2836		udev->rx_lanes = 1;
2837		udev->tx_lanes = 1;
2838	}
2839	if (hub_is_wusb(hub))
2840		udev->speed = USB_SPEED_WIRELESS;
2841	else if (hub_is_superspeedplus(hub->hdev) &&
2842		 port_speed_is_ssp(hub->hdev, ext_portstatus &
2843				   USB_EXT_PORT_STAT_RX_SPEED_ID))
2844		udev->speed = USB_SPEED_SUPER_PLUS;
2845	else if (hub_is_superspeed(hub->hdev))
2846		udev->speed = USB_SPEED_SUPER;
2847	else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
2848		udev->speed = USB_SPEED_HIGH;
2849	else if (portstatus & USB_PORT_STAT_LOW_SPEED)
2850		udev->speed = USB_SPEED_LOW;
2851	else
2852		udev->speed = USB_SPEED_FULL;
2853	return 0;
2854}
2855
2856/* Handle port reset and port warm(BH) reset (for USB3 protocol ports) */
2857static int hub_port_reset(struct usb_hub *hub, int port1,
2858			struct usb_device *udev, unsigned int delay, bool warm)
2859{
2860	int i, status;
2861	u16 portchange, portstatus;
2862	struct usb_port *port_dev = hub->ports[port1 - 1];
2863	int reset_recovery_time;
2864
2865	if (!hub_is_superspeed(hub->hdev)) {
2866		if (warm) {
2867			dev_err(hub->intfdev, "only USB3 hub support "
2868						"warm reset\n");
2869			return -EINVAL;
2870		}
2871		/* Block EHCI CF initialization during the port reset.
2872		 * Some companion controllers don't like it when they mix.
2873		 */
2874		down_read(&ehci_cf_port_reset_rwsem);
2875	} else if (!warm) {
2876		/*
2877		 * If the caller hasn't explicitly requested a warm reset,
2878		 * double check and see if one is needed.
2879		 */
2880		if (hub_port_status(hub, port1, &portstatus, &portchange) == 0)
2881			if (hub_port_warm_reset_required(hub, port1,
2882							portstatus))
2883				warm = true;
2884	}
2885	clear_bit(port1, hub->warm_reset_bits);
2886
2887	/* Reset the port */
2888	for (i = 0; i < PORT_RESET_TRIES; i++) {
2889		status = set_port_feature(hub->hdev, port1, (warm ?
2890					USB_PORT_FEAT_BH_PORT_RESET :
2891					USB_PORT_FEAT_RESET));
2892		if (status == -ENODEV) {
2893			;	/* The hub is gone */
2894		} else if (status) {
2895			dev_err(&port_dev->dev,
2896					"cannot %sreset (err = %d)\n",
2897					warm ? "warm " : "", status);
2898		} else {
2899			status = hub_port_wait_reset(hub, port1, udev, delay,
2900								warm);
2901			if (status && status != -ENOTCONN && status != -ENODEV)
2902				dev_dbg(hub->intfdev,
2903						"port_wait_reset: err = %d\n",
2904						status);
2905		}
2906
2907		/* Check for disconnect or reset */
2908		if (status == 0 || status == -ENOTCONN || status == -ENODEV) {
2909			usb_clear_port_feature(hub->hdev, port1,
2910					USB_PORT_FEAT_C_RESET);
2911
2912			if (!hub_is_superspeed(hub->hdev))
2913				goto done;
2914
2915			usb_clear_port_feature(hub->hdev, port1,
2916					USB_PORT_FEAT_C_BH_PORT_RESET);
2917			usb_clear_port_feature(hub->hdev, port1,
2918					USB_PORT_FEAT_C_PORT_LINK_STATE);
2919
2920			if (udev)
2921				usb_clear_port_feature(hub->hdev, port1,
2922					USB_PORT_FEAT_C_CONNECTION);
2923
2924			/*
2925			 * If a USB 3.0 device migrates from reset to an error
2926			 * state, re-issue the warm reset.
2927			 */
2928			if (hub_port_status(hub, port1,
2929					&portstatus, &portchange) < 0)
2930				goto done;
2931
2932			if (!hub_port_warm_reset_required(hub, port1,
2933					portstatus))
2934				goto done;
2935
2936			/*
2937			 * If the port is in SS.Inactive or Compliance Mode, the
2938			 * hot or warm reset failed.  Try another warm reset.
2939			 */
2940			if (!warm) {
2941				dev_dbg(&port_dev->dev,
2942						"hot reset failed, warm reset\n");
2943				warm = true;
2944			}
2945		}
2946
2947		dev_dbg(&port_dev->dev,
2948				"not enabled, trying %sreset again...\n",
2949				warm ? "warm " : "");
2950		delay = HUB_LONG_RESET_TIME;
2951	}
2952
2953	dev_err(&port_dev->dev, "Cannot enable. Maybe the USB cable is bad?\n");
2954
2955done:
2956	if (status == 0) {
2957		if (port_dev->quirks & USB_PORT_QUIRK_FAST_ENUM)
2958			usleep_range(10000, 12000);
2959		else {
2960			/* TRSTRCY = 10 ms; plus some extra */
2961			reset_recovery_time = 10 + 40;
2962
2963			/* Hub needs extra delay after resetting its port. */
2964			if (hub->hdev->quirks & USB_QUIRK_HUB_SLOW_RESET)
2965				reset_recovery_time += 100;
2966
2967			msleep(reset_recovery_time);
2968		}
2969
2970		if (udev) {
2971			struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2972
2973			update_devnum(udev, 0);
2974			/* The xHC may think the device is already reset,
2975			 * so ignore the status.
2976			 */
2977			if (hcd->driver->reset_device)
2978				hcd->driver->reset_device(hcd, udev);
2979
2980			usb_set_device_state(udev, USB_STATE_DEFAULT);
2981		}
2982	} else {
2983		if (udev)
2984			usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2985	}
2986
2987	if (!hub_is_superspeed(hub->hdev))
2988		up_read(&ehci_cf_port_reset_rwsem);
2989
2990	return status;
2991}
2992
2993/* Check if a port is power on */
2994static int port_is_power_on(struct usb_hub *hub, unsigned portstatus)
2995{
2996	int ret = 0;
2997
2998	if (hub_is_superspeed(hub->hdev)) {
2999		if (portstatus & USB_SS_PORT_STAT_POWER)
3000			ret = 1;
3001	} else {
3002		if (portstatus & USB_PORT_STAT_POWER)
3003			ret = 1;
3004	}
3005
3006	return ret;
3007}
3008
3009static void usb_lock_port(struct usb_port *port_dev)
3010		__acquires(&port_dev->status_lock)
3011{
3012	mutex_lock(&port_dev->status_lock);
3013	__acquire(&port_dev->status_lock);
3014}
3015
3016static void usb_unlock_port(struct usb_port *port_dev)
3017		__releases(&port_dev->status_lock)
3018{
3019	mutex_unlock(&port_dev->status_lock);
3020	__release(&port_dev->status_lock);
3021}
3022
3023#ifdef	CONFIG_PM
3024
3025/* Check if a port is suspended(USB2.0 port) or in U3 state(USB3.0 port) */
3026static int port_is_suspended(struct usb_hub *hub, unsigned portstatus)
3027{
3028	int ret = 0;
3029
3030	if (hub_is_superspeed(hub->hdev)) {
3031		if ((portstatus & USB_PORT_STAT_LINK_STATE)
3032				== USB_SS_PORT_LS_U3)
3033			ret = 1;
3034	} else {
3035		if (portstatus & USB_PORT_STAT_SUSPEND)
3036			ret = 1;
3037	}
3038
3039	return ret;
3040}
3041
3042/* Determine whether the device on a port is ready for a normal resume,
3043 * is ready for a reset-resume, or should be disconnected.
3044 */
3045static int check_port_resume_type(struct usb_device *udev,
3046		struct usb_hub *hub, int port1,
3047		int status, u16 portchange, u16 portstatus)
3048{
3049	struct usb_port *port_dev = hub->ports[port1 - 1];
3050	int retries = 3;
3051
3052 retry:
3053	/* Is a warm reset needed to recover the connection? */
3054	if (status == 0 && udev->reset_resume
3055		&& hub_port_warm_reset_required(hub, port1, portstatus)) {
3056		/* pass */;
3057	}
3058	/* Is the device still present? */
3059	else if (status || port_is_suspended(hub, portstatus) ||
3060			!port_is_power_on(hub, portstatus)) {
3061		if (status >= 0)
3062			status = -ENODEV;
3063	} else if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
3064		if (retries--) {
3065			usleep_range(200, 300);
3066			status = hub_port_status(hub, port1, &portstatus,
3067							     &portchange);
3068			goto retry;
3069		}
3070		status = -ENODEV;
3071	}
3072
3073	/* Can't do a normal resume if the port isn't enabled,
3074	 * so try a reset-resume instead.
3075	 */
3076	else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
3077		if (udev->persist_enabled)
3078			udev->reset_resume = 1;
3079		else
3080			status = -ENODEV;
3081	}
3082
3083	if (status) {
3084		dev_dbg(&port_dev->dev, "status %04x.%04x after resume, %d\n",
3085				portchange, portstatus, status);
3086	} else if (udev->reset_resume) {
3087
3088		/* Late port handoff can set status-change bits */
3089		if (portchange & USB_PORT_STAT_C_CONNECTION)
3090			usb_clear_port_feature(hub->hdev, port1,
3091					USB_PORT_FEAT_C_CONNECTION);
3092		if (portchange & USB_PORT_STAT_C_ENABLE)
3093			usb_clear_port_feature(hub->hdev, port1,
3094					USB_PORT_FEAT_C_ENABLE);
3095
3096		/*
3097		 * Whatever made this reset-resume necessary may have
3098		 * turned on the port1 bit in hub->change_bits.  But after
3099		 * a successful reset-resume we want the bit to be clear;
3100		 * if it was on it would indicate that something happened
3101		 * following the reset-resume.
3102		 */
3103		clear_bit(port1, hub->change_bits);
3104	}
3105
3106	return status;
3107}
3108
3109int usb_disable_ltm(struct usb_device *udev)
3110{
3111	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3112
3113	/* Check if the roothub and device supports LTM. */
3114	if (!usb_device_supports_ltm(hcd->self.root_hub) ||
3115			!usb_device_supports_ltm(udev))
3116		return 0;
3117
3118	/* Clear Feature LTM Enable can only be sent if the device is
3119	 * configured.
3120	 */
3121	if (!udev->actconfig)
3122		return 0;
3123
3124	return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3125			USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
3126			USB_DEVICE_LTM_ENABLE, 0, NULL, 0,
3127			USB_CTRL_SET_TIMEOUT);
3128}
3129EXPORT_SYMBOL_GPL(usb_disable_ltm);
3130
3131void usb_enable_ltm(struct usb_device *udev)
3132{
3133	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3134
3135	/* Check if the roothub and device supports LTM. */
3136	if (!usb_device_supports_ltm(hcd->self.root_hub) ||
3137			!usb_device_supports_ltm(udev))
3138		return;
3139
3140	/* Set Feature LTM Enable can only be sent if the device is
3141	 * configured.
3142	 */
3143	if (!udev->actconfig)
3144		return;
3145
3146	usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3147			USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
3148			USB_DEVICE_LTM_ENABLE, 0, NULL, 0,
3149			USB_CTRL_SET_TIMEOUT);
3150}
3151EXPORT_SYMBOL_GPL(usb_enable_ltm);
3152
3153/*
3154 * usb_enable_remote_wakeup - enable remote wakeup for a device
3155 * @udev: target device
3156 *
3157 * For USB-2 devices: Set the device's remote wakeup feature.
3158 *
3159 * For USB-3 devices: Assume there's only one function on the device and
3160 * enable remote wake for the first interface.  FIXME if the interface
3161 * association descriptor shows there's more than one function.
3162 */
3163static int usb_enable_remote_wakeup(struct usb_device *udev)
3164{
3165	if (udev->speed < USB_SPEED_SUPER)
3166		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3167				USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
3168				USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0,
3169				USB_CTRL_SET_TIMEOUT);
3170	else
3171		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3172				USB_REQ_SET_FEATURE, USB_RECIP_INTERFACE,
3173				USB_INTRF_FUNC_SUSPEND,
3174				USB_INTRF_FUNC_SUSPEND_RW |
3175					USB_INTRF_FUNC_SUSPEND_LP,
3176				NULL, 0, USB_CTRL_SET_TIMEOUT);
3177}
3178
3179/*
3180 * usb_disable_remote_wakeup - disable remote wakeup for a device
3181 * @udev: target device
3182 *
3183 * For USB-2 devices: Clear the device's remote wakeup feature.
3184 *
3185 * For USB-3 devices: Assume there's only one function on the device and
3186 * disable remote wake for the first interface.  FIXME if the interface
3187 * association descriptor shows there's more than one function.
3188 */
3189static int usb_disable_remote_wakeup(struct usb_device *udev)
3190{
3191	if (udev->speed < USB_SPEED_SUPER)
3192		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3193				USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
3194				USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0,
3195				USB_CTRL_SET_TIMEOUT);
3196	else
3197		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3198				USB_REQ_SET_FEATURE, USB_RECIP_INTERFACE,
3199				USB_INTRF_FUNC_SUSPEND,	0, NULL, 0,
3200				USB_CTRL_SET_TIMEOUT);
3201}
3202
3203/* Count of wakeup-enabled devices at or below udev */
3204unsigned usb_wakeup_enabled_descendants(struct usb_device *udev)
3205{
3206	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
3207
3208	return udev->do_remote_wakeup +
3209			(hub ? hub->wakeup_enabled_descendants : 0);
3210}
3211EXPORT_SYMBOL_GPL(usb_wakeup_enabled_descendants);
3212
3213/*
3214 * usb_port_suspend - suspend a usb device's upstream port
3215 * @udev: device that's no longer in active use, not a root hub
3216 * Context: must be able to sleep; device not locked; pm locks held
3217 *
3218 * Suspends a USB device that isn't in active use, conserving power.
3219 * Devices may wake out of a suspend, if anything important happens,
3220 * using the remote wakeup mechanism.  They may also be taken out of
3221 * suspend by the host, using usb_port_resume().  It's also routine
3222 * to disconnect devices while they are suspended.
3223 *
3224 * This only affects the USB hardware for a device; its interfaces
3225 * (and, for hubs, child devices) must already have been suspended.
3226 *
3227 * Selective port suspend reduces power; most suspended devices draw
3228 * less than 500 uA.  It's also used in OTG, along with remote wakeup.
3229 * All devices below the suspended port are also suspended.
3230 *
3231 * Devices leave suspend state when the host wakes them up.  Some devices
3232 * also support "remote wakeup", where the device can activate the USB
3233 * tree above them to deliver data, such as a keypress or packet.  In
3234 * some cases, this wakes the USB host.
3235 *
3236 * Suspending OTG devices may trigger HNP, if that's been enabled
3237 * between a pair of dual-role devices.  That will change roles, such
3238 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
3239 *
3240 * Devices on USB hub ports have only one "suspend" state, corresponding
3241 * to ACPI D2, "may cause the device to lose some context".
3242 * State transitions include:
3243 *
3244 *   - suspend, resume ... when the VBUS power link stays live
3245 *   - suspend, disconnect ... VBUS lost
3246 *
3247 * Once VBUS drop breaks the circuit, the port it's using has to go through
3248 * normal re-enumeration procedures, starting with enabling VBUS power.
3249 * Other than re-initializing the hub (plug/unplug, except for root hubs),
3250 * Linux (2.6) currently has NO mechanisms to initiate that:  no hub_wq
3251 * timer, no SRP, no requests through sysfs.
3252 *
3253 * If Runtime PM isn't enabled or used, non-SuperSpeed devices may not get
3254 * suspended until their bus goes into global suspend (i.e., the root
3255 * hub is suspended).  Nevertheless, we change @udev->state to
3256 * USB_STATE_SUSPENDED as this is the device's "logical" state.  The actual
3257 * upstream port setting is stored in @udev->port_is_suspended.
3258 *
3259 * Returns 0 on success, else negative errno.
3260 */
3261int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
3262{
3263	struct usb_hub	*hub = usb_hub_to_struct_hub(udev->parent);
3264	struct usb_port *port_dev = hub->ports[udev->portnum - 1];
3265	int		port1 = udev->portnum;
3266	int		status;
3267	bool		really_suspend = true;
3268
3269	usb_lock_port(port_dev);
3270
3271	/* enable remote wakeup when appropriate; this lets the device
3272	 * wake up the upstream hub (including maybe the root hub).
3273	 *
3274	 * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
3275	 * we don't explicitly enable it here.
3276	 */
3277	if (udev->do_remote_wakeup) {
3278		status = usb_enable_remote_wakeup(udev);
3279		if (status) {
3280			dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
3281					status);
3282			/* bail if autosuspend is requested */
3283			if (PMSG_IS_AUTO(msg))
3284				goto err_wakeup;
3285		}
3286	}
3287
3288	/* disable USB2 hardware LPM */
3289	usb_disable_usb2_hardware_lpm(udev);
3290
3291	if (usb_disable_ltm(udev)) {
3292		dev_err(&udev->dev, "Failed to disable LTM before suspend\n");
3293		status = -ENOMEM;
3294		if (PMSG_IS_AUTO(msg))
3295			goto err_ltm;
3296	}
3297
3298	/* see 7.1.7.6 */
3299	if (hub_is_superspeed(hub->hdev))
3300		status = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_U3);
3301
3302	/*
3303	 * For system suspend, we do not need to enable the suspend feature
3304	 * on individual USB-2 ports.  The devices will automatically go
3305	 * into suspend a few ms after the root hub stops sending packets.
3306	 * The USB 2.0 spec calls this "global suspend".
3307	 *
3308	 * However, many USB hubs have a bug: They don't relay wakeup requests
3309	 * from a downstream port if the port's suspend feature isn't on.
3310	 * Therefore we will turn on the suspend feature if udev or any of its
3311	 * descendants is enabled for remote wakeup.
3312	 */
3313	else if (PMSG_IS_AUTO(msg) || usb_wakeup_enabled_descendants(udev) > 0)
3314		status = set_port_feature(hub->hdev, port1,
3315				USB_PORT_FEAT_SUSPEND);
3316	else {
3317		really_suspend = false;
3318		status = 0;
3319	}
3320	if (status) {
3321		dev_dbg(&port_dev->dev, "can't suspend, status %d\n", status);
3322
3323		/* Try to enable USB3 LTM again */
3324		usb_enable_ltm(udev);
3325 err_ltm:
3326		/* Try to enable USB2 hardware LPM again */
3327		usb_enable_usb2_hardware_lpm(udev);
3328
3329		if (udev->do_remote_wakeup)
3330			(void) usb_disable_remote_wakeup(udev);
3331 err_wakeup:
3332
3333		/* System sleep transitions should never fail */
3334		if (!PMSG_IS_AUTO(msg))
3335			status = 0;
3336	} else {
3337		dev_dbg(&udev->dev, "usb %ssuspend, wakeup %d\n",
3338				(PMSG_IS_AUTO(msg) ? "auto-" : ""),
3339				udev->do_remote_wakeup);
3340		if (really_suspend) {
3341			udev->port_is_suspended = 1;
3342
3343			/* device has up to 10 msec to fully suspend */
3344			msleep(10);
3345		}
3346		usb_set_device_state(udev, USB_STATE_SUSPENDED);
3347	}
3348
3349	if (status == 0 && !udev->do_remote_wakeup && udev->persist_enabled
3350			&& test_and_clear_bit(port1, hub->child_usage_bits))
3351		pm_runtime_put_sync(&port_dev->dev);
3352
3353	usb_mark_last_busy(hub->hdev);
3354
3355	usb_unlock_port(port_dev);
3356	return status;
3357}
3358
3359/*
3360 * If the USB "suspend" state is in use (rather than "global suspend"),
3361 * many devices will be individually taken out of suspend state using
3362 * special "resume" signaling.  This routine kicks in shortly after
3363 * hardware resume signaling is finished, either because of selective
3364 * resume (by host) or remote wakeup (by device) ... now see what changed
3365 * in the tree that's rooted at this device.
3366 *
3367 * If @udev->reset_resume is set then the device is reset before the
3368 * status check is done.
3369 */
3370static int finish_port_resume(struct usb_device *udev)
3371{
3372	int	status = 0;
3373	u16	devstatus = 0;
3374
3375	/* caller owns the udev device lock */
3376	dev_dbg(&udev->dev, "%s\n",
3377		udev->reset_resume ? "finish reset-resume" : "finish resume");
3378
3379	/* usb ch9 identifies four variants of SUSPENDED, based on what
3380	 * state the device resumes to.  Linux currently won't see the
3381	 * first two on the host side; they'd be inside hub_port_init()
3382	 * during many timeouts, but hub_wq can't suspend until later.
3383	 */
3384	usb_set_device_state(udev, udev->actconfig
3385			? USB_STATE_CONFIGURED
3386			: USB_STATE_ADDRESS);
3387
3388	/* 10.5.4.5 says not to reset a suspended port if the attached
3389	 * device is enabled for remote wakeup.  Hence the reset
3390	 * operation is carried out here, after the port has been
3391	 * resumed.
3392	 */
3393	if (udev->reset_resume) {
3394		/*
3395		 * If the device morphs or switches modes when it is reset,
3396		 * we don't want to perform a reset-resume.  We'll fail the
3397		 * resume, which will cause a logical disconnect, and then
3398		 * the device will be rediscovered.
3399		 */
3400 retry_reset_resume:
3401		if (udev->quirks & USB_QUIRK_RESET)
3402			status = -ENODEV;
3403		else
3404			status = usb_reset_and_verify_device(udev);
3405	}
3406
3407	/* 10.5.4.5 says be sure devices in the tree are still there.
3408	 * For now let's assume the device didn't go crazy on resume,
3409	 * and device drivers will know about any resume quirks.
3410	 */
3411	if (status == 0) {
3412		devstatus = 0;
3413		status = usb_get_std_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
3414
3415		/* If a normal resume failed, try doing a reset-resume */
3416		if (status && !udev->reset_resume && udev->persist_enabled) {
3417			dev_dbg(&udev->dev, "retry with reset-resume\n");
3418			udev->reset_resume = 1;
3419			goto retry_reset_resume;
3420		}
3421	}
3422
3423	if (status) {
3424		dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
3425				status);
3426	/*
3427	 * There are a few quirky devices which violate the standard
3428	 * by claiming to have remote wakeup enabled after a reset,
3429	 * which crash if the feature is cleared, hence check for
3430	 * udev->reset_resume
3431	 */
3432	} else if (udev->actconfig && !udev->reset_resume) {
3433		if (udev->speed < USB_SPEED_SUPER) {
3434			if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
3435				status = usb_disable_remote_wakeup(udev);
3436		} else {
3437			status = usb_get_std_status(udev, USB_RECIP_INTERFACE, 0,
3438					&devstatus);
3439			if (!status && devstatus & (USB_INTRF_STAT_FUNC_RW_CAP
3440					| USB_INTRF_STAT_FUNC_RW))
3441				status = usb_disable_remote_wakeup(udev);
3442		}
3443
3444		if (status)
3445			dev_dbg(&udev->dev,
3446				"disable remote wakeup, status %d\n",
3447				status);
3448		status = 0;
3449	}
3450	return status;
3451}
3452
3453/*
3454 * There are some SS USB devices which take longer time for link training.
3455 * XHCI specs 4.19.4 says that when Link training is successful, port
3456 * sets CCS bit to 1. So if SW reads port status before successful link
3457 * training, then it will not find device to be present.
3458 * USB Analyzer log with such buggy devices show that in some cases
3459 * device switch on the RX termination after long delay of host enabling
3460 * the VBUS. In few other cases it has been seen that device fails to
3461 * negotiate link training in first attempt. It has been
3462 * reported till now that few devices take as long as 2000 ms to train
3463 * the link after host enabling its VBUS and termination. Following
3464 * routine implements a 2000 ms timeout for link training. If in a case
3465 * link trains before timeout, loop will exit earlier.
3466 *
3467 * There are also some 2.0 hard drive based devices and 3.0 thumb
3468 * drives that, when plugged into a 2.0 only port, take a long
3469 * time to set CCS after VBUS enable.
3470 *
3471 * FIXME: If a device was connected before suspend, but was removed
3472 * while system was asleep, then the loop in the following routine will
3473 * only exit at timeout.
3474 *
3475 * This routine should only be called when persist is enabled.
3476 */
3477static int wait_for_connected(struct usb_device *udev,
3478		struct usb_hub *hub, int *port1,
3479		u16 *portchange, u16 *portstatus)
3480{
3481	int status = 0, delay_ms = 0;
3482
3483	while (delay_ms < 2000) {
3484		if (status || *portstatus & USB_PORT_STAT_CONNECTION)
3485			break;
3486		if (!port_is_power_on(hub, *portstatus)) {
3487			status = -ENODEV;
3488			break;
3489		}
3490		msleep(20);
3491		delay_ms += 20;
3492		status = hub_port_status(hub, *port1, portstatus, portchange);
3493	}
3494	dev_dbg(&udev->dev, "Waited %dms for CONNECT\n", delay_ms);
3495	return status;
3496}
3497
3498/*
3499 * usb_port_resume - re-activate a suspended usb device's upstream port
3500 * @udev: device to re-activate, not a root hub
3501 * Context: must be able to sleep; device not locked; pm locks held
3502 *
3503 * This will re-activate the suspended device, increasing power usage
3504 * while letting drivers communicate again with its endpoints.
3505 * USB resume explicitly guarantees that the power session between
3506 * the host and the device is the same as it was when the device
3507 * suspended.
3508 *
3509 * If @udev->reset_resume is set then this routine won't check that the
3510 * port is still enabled.  Furthermore, finish_port_resume() above will
3511 * reset @udev.  The end result is that a broken power session can be
3512 * recovered and @udev will appear to persist across a loss of VBUS power.
3513 *
3514 * For example, if a host controller doesn't maintain VBUS suspend current
3515 * during a system sleep or is reset when the system wakes up, all the USB
3516 * power sessions below it will be broken.  This is especially troublesome
3517 * for mass-storage devices containing mounted filesystems, since the
3518 * device will appear to have disconnected and all the memory mappings
3519 * to it will be lost.  Using the USB_PERSIST facility, the device can be
3520 * made to appear as if it had not disconnected.
3521 *
3522 * This facility can be dangerous.  Although usb_reset_and_verify_device() makes
3523 * every effort to insure that the same device is present after the
3524 * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
3525 * quite possible for a device to remain unaltered but its media to be
3526 * changed.  If the user replaces a flash memory card while the system is
3527 * asleep, he will have only himself to blame when the filesystem on the
3528 * new card is corrupted and the system crashes.
3529 *
3530 * Returns 0 on success, else negative errno.
3531 */
3532int usb_port_resume(struct usb_device *udev, pm_message_t msg)
3533{
3534	struct usb_hub	*hub = usb_hub_to_struct_hub(udev->parent);
3535	struct usb_port *port_dev = hub->ports[udev->portnum  - 1];
3536	int		port1 = udev->portnum;
3537	int		status;
3538	u16		portchange, portstatus;
3539
3540	if (!test_and_set_bit(port1, hub->child_usage_bits)) {
3541		status = pm_runtime_get_sync(&port_dev->dev);
3542		if (status < 0) {
3543			dev_dbg(&udev->dev, "can't resume usb port, status %d\n",
3544					status);
3545			return status;
3546		}
3547	}
3548
3549	usb_lock_port(port_dev);
3550
3551	/* Skip the initial Clear-Suspend step for a remote wakeup */
3552	status = hub_port_status(hub, port1, &portstatus, &portchange);
3553	if (status == 0 && !port_is_suspended(hub, portstatus)) {
3554		if (portchange & USB_PORT_STAT_C_SUSPEND)
3555			pm_wakeup_event(&udev->dev, 0);
3556		goto SuspendCleared;
3557	}
3558
3559	/* see 7.1.7.7; affects power usage, but not budgeting */
3560	if (hub_is_superspeed(hub->hdev))
3561		status = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_U0);
3562	else
3563		status = usb_clear_port_feature(hub->hdev,
3564				port1, USB_PORT_FEAT_SUSPEND);
3565	if (status) {
3566		dev_dbg(&port_dev->dev, "can't resume, status %d\n", status);
3567	} else {
3568		/* drive resume for USB_RESUME_TIMEOUT msec */
3569		dev_dbg(&udev->dev, "usb %sresume\n",
3570				(PMSG_IS_AUTO(msg) ? "auto-" : ""));
3571		msleep(USB_RESUME_TIMEOUT);
3572
3573		/* Virtual root hubs can trigger on GET_PORT_STATUS to
3574		 * stop resume signaling.  Then finish the resume
3575		 * sequence.
3576		 */
3577		status = hub_port_status(hub, port1, &portstatus, &portchange);
3578
3579		/* TRSMRCY = 10 msec */
3580		msleep(10);
3581	}
3582
3583 SuspendCleared:
3584	if (status == 0) {
3585		udev->port_is_suspended = 0;
3586		if (hub_is_superspeed(hub->hdev)) {
3587			if (portchange & USB_PORT_STAT_C_LINK_STATE)
3588				usb_clear_port_feature(hub->hdev, port1,
3589					USB_PORT_FEAT_C_PORT_LINK_STATE);
3590		} else {
3591			if (portchange & USB_PORT_STAT_C_SUSPEND)
3592				usb_clear_port_feature(hub->hdev, port1,
3593						USB_PORT_FEAT_C_SUSPEND);
3594		}
3595	}
3596
3597	if (udev->persist_enabled)
3598		status = wait_for_connected(udev, hub, &port1, &portchange,
3599				&portstatus);
3600
3601	status = check_port_resume_type(udev,
3602			hub, port1, status, portchange, portstatus);
3603	if (status == 0)
3604		status = finish_port_resume(udev);
3605	if (status < 0) {
3606		dev_dbg(&udev->dev, "can't resume, status %d\n", status);
3607		hub_port_logical_disconnect(hub, port1);
3608	} else  {
3609		/* Try to enable USB2 hardware LPM */
3610		usb_enable_usb2_hardware_lpm(udev);
3611
3612		/* Try to enable USB3 LTM */
3613		usb_enable_ltm(udev);
3614	}
3615
3616	usb_unlock_port(port_dev);
3617
3618	return status;
3619}
3620
3621int usb_remote_wakeup(struct usb_device *udev)
3622{
3623	int	status = 0;
3624
3625	usb_lock_device(udev);
3626	if (udev->state == USB_STATE_SUSPENDED) {
3627		dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
3628		status = usb_autoresume_device(udev);
3629		if (status == 0) {
3630			/* Let the drivers do their thing, then... */
3631			usb_autosuspend_device(udev);
3632		}
3633	}
3634	usb_unlock_device(udev);
3635	return status;
3636}
3637
3638/* Returns 1 if there was a remote wakeup and a connect status change. */
3639static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
3640		u16 portstatus, u16 portchange)
3641		__must_hold(&port_dev->status_lock)
3642{
3643	struct usb_port *port_dev = hub->ports[port - 1];
3644	struct usb_device *hdev;
3645	struct usb_device *udev;
3646	int connect_change = 0;
3647	u16 link_state;
3648	int ret;
3649
3650	hdev = hub->hdev;
3651	udev = port_dev->child;
3652	if (!hub_is_superspeed(hdev)) {
3653		if (!(portchange & USB_PORT_STAT_C_SUSPEND))
3654			return 0;
3655		usb_clear_port_feature(hdev, port, USB_PORT_FEAT_C_SUSPEND);
3656	} else {
3657		link_state = portstatus & USB_PORT_STAT_LINK_STATE;
3658		if (!udev || udev->state != USB_STATE_SUSPENDED ||
3659				(link_state != USB_SS_PORT_LS_U0 &&
3660				 link_state != USB_SS_PORT_LS_U1 &&
3661				 link_state != USB_SS_PORT_LS_U2))
3662			return 0;
3663	}
3664
3665	if (udev) {
3666		/* TRSMRCY = 10 msec */
3667		msleep(10);
3668
3669		usb_unlock_port(port_dev);
3670		ret = usb_remote_wakeup(udev);
3671		usb_lock_port(port_dev);
3672		if (ret < 0)
3673			connect_change = 1;
3674	} else {
3675		ret = -ENODEV;
3676		hub_port_disable(hub, port, 1);
3677	}
3678	dev_dbg(&port_dev->dev, "resume, status %d\n", ret);
3679	return connect_change;
3680}
3681
3682static int check_ports_changed(struct usb_hub *hub)
3683{
3684	int port1;
3685
3686	for (port1 = 1; port1 <= hub->hdev->maxchild; ++port1) {
3687		u16 portstatus, portchange;
3688		int status;
3689
3690		status = hub_port_status(hub, port1, &portstatus, &portchange);
3691		if (!status && portchange)
3692			return 1;
3693	}
3694	return 0;
3695}
3696
3697static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
3698{
3699	struct usb_hub		*hub = usb_get_intfdata(intf);
3700	struct usb_device	*hdev = hub->hdev;
3701	unsigned		port1;
3702
3703	/*
3704	 * Warn if children aren't already suspended.
3705	 * Also, add up the number of wakeup-enabled descendants.
3706	 */
3707	hub->wakeup_enabled_descendants = 0;
3708	for (port1 = 1; port1 <= hdev->maxchild; port1++) {
3709		struct usb_port *port_dev = hub->ports[port1 - 1];
3710		struct usb_device *udev = port_dev->child;
3711
3712		if (udev && udev->can_submit) {
3713			dev_warn(&port_dev->dev, "device %s not suspended yet\n",
3714					dev_name(&udev->dev));
3715			if (PMSG_IS_AUTO(msg))
3716				return -EBUSY;
3717		}
3718		if (udev)
3719			hub->wakeup_enabled_descendants +=
3720					usb_wakeup_enabled_descendants(udev);
3721	}
3722
3723	if (hdev->do_remote_wakeup && hub->quirk_check_port_auto_suspend) {
3724		/* check if there are changes pending on hub ports */
3725		if (check_ports_changed(hub)) {
3726			if (PMSG_IS_AUTO(msg))
3727				return -EBUSY;
3728			pm_wakeup_event(&hdev->dev, 2000);
3729		}
3730	}
3731
3732	if (hub_is_superspeed(hdev) && hdev->do_remote_wakeup) {
3733		/* Enable hub to send remote wakeup for all ports. */
3734		for (port1 = 1; port1 <= hdev->maxchild; port1++) {
3735			set_port_feature(hdev,
3736					 port1 |
3737					 USB_PORT_FEAT_REMOTE_WAKE_CONNECT |
3738					 USB_PORT_FEAT_REMOTE_WAKE_DISCONNECT |
3739					 USB_PORT_FEAT_REMOTE_WAKE_OVER_CURRENT,
3740					 USB_PORT_FEAT_REMOTE_WAKE_MASK);
3741		}
3742	}
3743
3744	dev_dbg(&intf->dev, "%s\n", __func__);
3745
3746	/* stop hub_wq and related activity */
3747	hub_quiesce(hub, HUB_SUSPEND);
3748	return 0;
3749}
3750
3751/* Report wakeup requests from the ports of a resuming root hub */
3752static void report_wakeup_requests(struct usb_hub *hub)
3753{
3754	struct usb_device	*hdev = hub->hdev;
3755	struct usb_device	*udev;
3756	struct usb_hcd		*hcd;
3757	unsigned long		resuming_ports;
3758	int			i;
3759
3760	if (hdev->parent)
3761		return;		/* Not a root hub */
3762
3763	hcd = bus_to_hcd(hdev->bus);
3764	if (hcd->driver->get_resuming_ports) {
3765
3766		/*
3767		 * The get_resuming_ports() method returns a bitmap (origin 0)
3768		 * of ports which have started wakeup signaling but have not
3769		 * yet finished resuming.  During system resume we will
3770		 * resume all the enabled ports, regardless of any wakeup
3771		 * signals, which means the wakeup requests would be lost.
3772		 * To prevent this, report them to the PM core here.
3773		 */
3774		resuming_ports = hcd->driver->get_resuming_ports(hcd);
3775		for (i = 0; i < hdev->maxchild; ++i) {
3776			if (test_bit(i, &resuming_ports)) {
3777				udev = hub->ports[i]->child;
3778				if (udev)
3779					pm_wakeup_event(&udev->dev, 0);
3780			}
3781		}
3782	}
3783}
3784
3785static int hub_resume(struct usb_interface *intf)
3786{
3787	struct usb_hub *hub = usb_get_intfdata(intf);
3788
3789	dev_dbg(&intf->dev, "%s\n", __func__);
3790	hub_activate(hub, HUB_RESUME);
3791
3792	/*
3793	 * This should be called only for system resume, not runtime resume.
3794	 * We can't tell the difference here, so some wakeup requests will be
3795	 * reported at the wrong time or more than once.  This shouldn't
3796	 * matter much, so long as they do get reported.
3797	 */
3798	report_wakeup_requests(hub);
3799	return 0;
3800}
3801
3802static int hub_reset_resume(struct usb_interface *intf)
3803{
3804	struct usb_hub *hub = usb_get_intfdata(intf);
3805
3806	dev_dbg(&intf->dev, "%s\n", __func__);
3807	hub_activate(hub, HUB_RESET_RESUME);
3808	return 0;
3809}
3810
3811/**
3812 * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
3813 * @rhdev: struct usb_device for the root hub
3814 *
3815 * The USB host controller driver calls this function when its root hub
3816 * is resumed and Vbus power has been interrupted or the controller
3817 * has been reset.  The routine marks @rhdev as having lost power.
3818 * When the hub driver is resumed it will take notice and carry out
3819 * power-session recovery for all the "USB-PERSIST"-enabled child devices;
3820 * the others will be disconnected.
3821 */
3822void usb_root_hub_lost_power(struct usb_device *rhdev)
3823{
3824	dev_notice(&rhdev->dev, "root hub lost power or was reset\n");
3825	rhdev->reset_resume = 1;
3826}
3827EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
3828
3829static const char * const usb3_lpm_names[]  = {
3830	"U0",
3831	"U1",
3832	"U2",
3833	"U3",
3834};
3835
3836/*
3837 * Send a Set SEL control transfer to the device, prior to enabling
3838 * device-initiated U1 or U2.  This lets the device know the exit latencies from
3839 * the time the device initiates a U1 or U2 exit, to the time it will receive a
3840 * packet from the host.
3841 *
3842 * This function will fail if the SEL or PEL values for udev are greater than
3843 * the maximum allowed values for the link state to be enabled.
3844 */
3845static int usb_req_set_sel(struct usb_device *udev, enum usb3_link_state state)
3846{
3847	struct usb_set_sel_req *sel_values;
3848	unsigned long long u1_sel;
3849	unsigned long long u1_pel;
3850	unsigned long long u2_sel;
3851	unsigned long long u2_pel;
3852	int ret;
3853
3854	if (udev->state != USB_STATE_CONFIGURED)
3855		return 0;
3856
3857	/* Convert SEL and PEL stored in ns to us */
3858	u1_sel = DIV_ROUND_UP(udev->u1_params.sel, 1000);
3859	u1_pel = DIV_ROUND_UP(udev->u1_params.pel, 1000);
3860	u2_sel = DIV_ROUND_UP(udev->u2_params.sel, 1000);
3861	u2_pel = DIV_ROUND_UP(udev->u2_params.pel, 1000);
3862
3863	/*
3864	 * Make sure that the calculated SEL and PEL values for the link
3865	 * state we're enabling aren't bigger than the max SEL/PEL
3866	 * value that will fit in the SET SEL control transfer.
3867	 * Otherwise the device would get an incorrect idea of the exit
3868	 * latency for the link state, and could start a device-initiated
3869	 * U1/U2 when the exit latencies are too high.
3870	 */
3871	if ((state == USB3_LPM_U1 &&
3872				(u1_sel > USB3_LPM_MAX_U1_SEL_PEL ||
3873				 u1_pel > USB3_LPM_MAX_U1_SEL_PEL)) ||
3874			(state == USB3_LPM_U2 &&
3875			 (u2_sel > USB3_LPM_MAX_U2_SEL_PEL ||
3876			  u2_pel > USB3_LPM_MAX_U2_SEL_PEL))) {
3877		dev_dbg(&udev->dev, "Device-initiated %s disabled due to long SEL %llu us or PEL %llu us\n",
3878				usb3_lpm_names[state], u1_sel, u1_pel);
3879		return -EINVAL;
3880	}
3881
3882	/*
3883	 * If we're enabling device-initiated LPM for one link state,
3884	 * but the other link state has a too high SEL or PEL value,
3885	 * just set those values to the max in the Set SEL request.
3886	 */
3887	if (u1_sel > USB3_LPM_MAX_U1_SEL_PEL)
3888		u1_sel = USB3_LPM_MAX_U1_SEL_PEL;
3889
3890	if (u1_pel > USB3_LPM_MAX_U1_SEL_PEL)
3891		u1_pel = USB3_LPM_MAX_U1_SEL_PEL;
3892
3893	if (u2_sel > USB3_LPM_MAX_U2_SEL_PEL)
3894		u2_sel = USB3_LPM_MAX_U2_SEL_PEL;
3895
3896	if (u2_pel > USB3_LPM_MAX_U2_SEL_PEL)
3897		u2_pel = USB3_LPM_MAX_U2_SEL_PEL;
3898
3899	/*
3900	 * usb_enable_lpm() can be called as part of a failed device reset,
3901	 * which may be initiated by an error path of a mass storage driver.
3902	 * Therefore, use GFP_NOIO.
3903	 */
3904	sel_values = kmalloc(sizeof *(sel_values), GFP_NOIO);
3905	if (!sel_values)
3906		return -ENOMEM;
3907
3908	sel_values->u1_sel = u1_sel;
3909	sel_values->u1_pel = u1_pel;
3910	sel_values->u2_sel = cpu_to_le16(u2_sel);
3911	sel_values->u2_pel = cpu_to_le16(u2_pel);
3912
3913	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3914			USB_REQ_SET_SEL,
3915			USB_RECIP_DEVICE,
3916			0, 0,
3917			sel_values, sizeof *(sel_values),
3918			USB_CTRL_SET_TIMEOUT);
3919	kfree(sel_values);
3920	return ret;
3921}
3922
3923/*
3924 * Enable or disable device-initiated U1 or U2 transitions.
3925 */
3926static int usb_set_device_initiated_lpm(struct usb_device *udev,
3927		enum usb3_link_state state, bool enable)
3928{
3929	int ret;
3930	int feature;
3931
3932	switch (state) {
3933	case USB3_LPM_U1:
3934		feature = USB_DEVICE_U1_ENABLE;
3935		break;
3936	case USB3_LPM_U2:
3937		feature = USB_DEVICE_U2_ENABLE;
3938		break;
3939	default:
3940		dev_warn(&udev->dev, "%s: Can't %s non-U1 or U2 state.\n",
3941				__func__, enable ? "enable" : "disable");
3942		return -EINVAL;
3943	}
3944
3945	if (udev->state != USB_STATE_CONFIGURED) {
3946		dev_dbg(&udev->dev, "%s: Can't %s %s state "
3947				"for unconfigured device.\n",
3948				__func__, enable ? "enable" : "disable",
3949				usb3_lpm_names[state]);
3950		return 0;
3951	}
3952
3953	if (enable) {
3954		/*
3955		 * Now send the control transfer to enable device-initiated LPM
3956		 * for either U1 or U2.
3957		 */
3958		ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3959				USB_REQ_SET_FEATURE,
3960				USB_RECIP_DEVICE,
3961				feature,
3962				0, NULL, 0,
3963				USB_CTRL_SET_TIMEOUT);
3964	} else {
3965		ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3966				USB_REQ_CLEAR_FEATURE,
3967				USB_RECIP_DEVICE,
3968				feature,
3969				0, NULL, 0,
3970				USB_CTRL_SET_TIMEOUT);
3971	}
3972	if (ret < 0) {
3973		dev_warn(&udev->dev, "%s of device-initiated %s failed.\n",
3974				enable ? "Enable" : "Disable",
3975				usb3_lpm_names[state]);
3976		return -EBUSY;
3977	}
3978	return 0;
3979}
3980
3981static int usb_set_lpm_timeout(struct usb_device *udev,
3982		enum usb3_link_state state, int timeout)
3983{
3984	int ret;
3985	int feature;
3986
3987	switch (state) {
3988	case USB3_LPM_U1:
3989		feature = USB_PORT_FEAT_U1_TIMEOUT;
3990		break;
3991	case USB3_LPM_U2:
3992		feature = USB_PORT_FEAT_U2_TIMEOUT;
3993		break;
3994	default:
3995		dev_warn(&udev->dev, "%s: Can't set timeout for non-U1 or U2 state.\n",
3996				__func__);
3997		return -EINVAL;
3998	}
3999
4000	if (state == USB3_LPM_U1 && timeout > USB3_LPM_U1_MAX_TIMEOUT &&
4001			timeout != USB3_LPM_DEVICE_INITIATED) {
4002		dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x, "
4003				"which is a reserved value.\n",
4004				usb3_lpm_names[state], timeout);
4005		return -EINVAL;
4006	}
4007
4008	ret = set_port_feature(udev->parent,
4009			USB_PORT_LPM_TIMEOUT(timeout) | udev->portnum,
4010			feature);
4011	if (ret < 0) {
4012		dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x,"
4013				"error code %i\n", usb3_lpm_names[state],
4014				timeout, ret);
4015		return -EBUSY;
4016	}
4017	if (state == USB3_LPM_U1)
4018		udev->u1_params.timeout = timeout;
4019	else
4020		udev->u2_params.timeout = timeout;
4021	return 0;
4022}
4023
4024/*
4025 * Enable the hub-initiated U1/U2 idle timeouts, and enable device-initiated
4026 * U1/U2 entry.
4027 *
4028 * We will attempt to enable U1 or U2, but there are no guarantees that the
4029 * control transfers to set the hub timeout or enable device-initiated U1/U2
4030 * will be successful.
4031 *
4032 * If the control transfer to enable device-initiated U1/U2 entry fails, then
4033 * hub-initiated U1/U2 will be disabled.
4034 *
4035 * If we cannot set the parent hub U1/U2 timeout, we attempt to let the xHCI
4036 * driver know about it.  If that call fails, it should be harmless, and just
4037 * take up more slightly more bus bandwidth for unnecessary U1/U2 exit latency.
4038 */
4039static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
4040		enum usb3_link_state state)
4041{
4042	int timeout, ret;
4043	__u8 u1_mel = udev->bos->ss_cap->bU1devExitLat;
4044	__le16 u2_mel = udev->bos->ss_cap->bU2DevExitLat;
4045
4046	/* If the device says it doesn't have *any* exit latency to come out of
4047	 * U1 or U2, it's probably lying.  Assume it doesn't implement that link
4048	 * state.
4049	 */
4050	if ((state == USB3_LPM_U1 && u1_mel == 0) ||
4051			(state == USB3_LPM_U2 && u2_mel == 0))
4052		return;
4053
4054	/*
4055	 * First, let the device know about the exit latencies
4056	 * associated with the link state we're about to enable.
4057	 */
4058	ret = usb_req_set_sel(udev, state);
4059	if (ret < 0) {
4060		dev_warn(&udev->dev, "Set SEL for device-initiated %s failed.\n",
4061				usb3_lpm_names[state]);
4062		return;
4063	}
4064
4065	/* We allow the host controller to set the U1/U2 timeout internally
4066	 * first, so that it can change its schedule to account for the
4067	 * additional latency to send data to a device in a lower power
4068	 * link state.
4069	 */
4070	timeout = hcd->driver->enable_usb3_lpm_timeout(hcd, udev, state);
4071
4072	/* xHCI host controller doesn't want to enable this LPM state. */
4073	if (timeout == 0)
4074		return;
4075
4076	if (timeout < 0) {
4077		dev_warn(&udev->dev, "Could not enable %s link state, "
4078				"xHCI error %i.\n", usb3_lpm_names[state],
4079				timeout);
4080		return;
4081	}
4082
4083	if (usb_set_lpm_timeout(udev, state, timeout)) {
4084		/* If we can't set the parent hub U1/U2 timeout,
4085		 * device-initiated LPM won't be allowed either, so let the xHCI
4086		 * host know that this link state won't be enabled.
4087		 */
4088		hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
4089		return;
4090	}
4091
4092	/* Only a configured device will accept the Set Feature
4093	 * U1/U2_ENABLE
4094	 */
4095	if (udev->actconfig &&
4096	    usb_set_device_initiated_lpm(udev, state, true) == 0) {
4097		if (state == USB3_LPM_U1)
4098			udev->usb3_lpm_u1_enabled = 1;
4099		else if (state == USB3_LPM_U2)
4100			udev->usb3_lpm_u2_enabled = 1;
4101	} else {
4102		/* Don't request U1/U2 entry if the device
4103		 * cannot transition to U1/U2.
4104		 */
4105		usb_set_lpm_timeout(udev, state, 0);
4106		hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
4107	}
4108}
4109
4110/*
4111 * Disable the hub-initiated U1/U2 idle timeouts, and disable device-initiated
4112 * U1/U2 entry.
4113 *
4114 * If this function returns -EBUSY, the parent hub will still allow U1/U2 entry.
4115 * If zero is returned, the parent will not allow the link to go into U1/U2.
4116 *
4117 * If zero is returned, device-initiated U1/U2 entry may still be enabled, but
4118 * it won't have an effect on the bus link state because the parent hub will
4119 * still disallow device-initiated U1/U2 entry.
4120 *
4121 * If zero is returned, the xHCI host controller may still think U1/U2 entry is
4122 * possible.  The result will be slightly more bus bandwidth will be taken up
4123 * (to account for U1/U2 exit latency), but it should be harmless.
4124 */
4125static int usb_disable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
4126		enum usb3_link_state state)
4127{
4128	switch (state) {
4129	case USB3_LPM_U1:
4130	case USB3_LPM_U2:
4131		break;
4132	default:
4133		dev_warn(&udev->dev, "%s: Can't disable non-U1 or U2 state.\n",
4134				__func__);
4135		return -EINVAL;
4136	}
4137
4138	if (usb_set_lpm_timeout(udev, state, 0))
4139		return -EBUSY;
4140
4141	usb_set_device_initiated_lpm(udev, state, false);
4142
4143	if (hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state))
4144		dev_warn(&udev->dev, "Could not disable xHCI %s timeout, "
4145				"bus schedule bandwidth may be impacted.\n",
4146				usb3_lpm_names[state]);
4147
4148	/* As soon as usb_set_lpm_timeout(0) return 0, hub initiated LPM
4149	 * is disabled. Hub will disallows link to enter U1/U2 as well,
4150	 * even device is initiating LPM. Hence LPM is disabled if hub LPM
4151	 * timeout set to 0, no matter device-initiated LPM is disabled or
4152	 * not.
4153	 */
4154	if (state == USB3_LPM_U1)
4155		udev->usb3_lpm_u1_enabled = 0;
4156	else if (state == USB3_LPM_U2)
4157		udev->usb3_lpm_u2_enabled = 0;
4158
4159	return 0;
4160}
4161
4162/*
4163 * Disable hub-initiated and device-initiated U1 and U2 entry.
4164 * Caller must own the bandwidth_mutex.
4165 *
4166 * This will call usb_enable_lpm() on failure, which will decrement
4167 * lpm_disable_count, and will re-enable LPM if lpm_disable_count reaches zero.
4168 */
4169int usb_disable_lpm(struct usb_device *udev)
4170{
4171	struct usb_hcd *hcd;
4172
4173	if (!udev || !udev->parent ||
4174			udev->speed < USB_SPEED_SUPER ||
4175			!udev->lpm_capable ||
4176			udev->state < USB_STATE_CONFIGURED)
4177		return 0;
4178
4179	hcd = bus_to_hcd(udev->bus);
4180	if (!hcd || !hcd->driver->disable_usb3_lpm_timeout)
4181		return 0;
4182
4183	udev->lpm_disable_count++;
4184	if ((udev->u1_params.timeout == 0 && udev->u2_params.timeout == 0))
4185		return 0;
4186
4187	/* If LPM is enabled, attempt to disable it. */
4188	if (usb_disable_link_state(hcd, udev, USB3_LPM_U1))
4189		goto enable_lpm;
4190	if (usb_disable_link_state(hcd, udev, USB3_LPM_U2))
4191		goto enable_lpm;
4192
4193	return 0;
4194
4195enable_lpm:
4196	usb_enable_lpm(udev);
4197	return -EBUSY;
4198}
4199EXPORT_SYMBOL_GPL(usb_disable_lpm);
4200
4201/* Grab the bandwidth_mutex before calling usb_disable_lpm() */
4202int usb_unlocked_disable_lpm(struct usb_device *udev)
4203{
4204	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4205	int ret;
4206
4207	if (!hcd)
4208		return -EINVAL;
4209
4210	mutex_lock(hcd->bandwidth_mutex);
4211	ret = usb_disable_lpm(udev);
4212	mutex_unlock(hcd->bandwidth_mutex);
4213
4214	return ret;
4215}
4216EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
4217
4218/*
4219 * Attempt to enable device-initiated and hub-initiated U1 and U2 entry.  The
4220 * xHCI host policy may prevent U1 or U2 from being enabled.
4221 *
4222 * Other callers may have disabled link PM, so U1 and U2 entry will be disabled
4223 * until the lpm_disable_count drops to zero.  Caller must own the
4224 * bandwidth_mutex.
4225 */
4226void usb_enable_lpm(struct usb_device *udev)
4227{
4228	struct usb_hcd *hcd;
4229	struct usb_hub *hub;
4230	struct usb_port *port_dev;
4231
4232	if (!udev || !udev->parent ||
4233			udev->speed < USB_SPEED_SUPER ||
4234			!udev->lpm_capable ||
4235			udev->state < USB_STATE_CONFIGURED)
4236		return;
4237
4238	udev->lpm_disable_count--;
4239	hcd = bus_to_hcd(udev->bus);
4240	/* Double check that we can both enable and disable LPM.
4241	 * Device must be configured to accept set feature U1/U2 timeout.
4242	 */
4243	if (!hcd || !hcd->driver->enable_usb3_lpm_timeout ||
4244			!hcd->driver->disable_usb3_lpm_timeout)
4245		return;
4246
4247	if (udev->lpm_disable_count > 0)
4248		return;
4249
4250	hub = usb_hub_to_struct_hub(udev->parent);
4251	if (!hub)
4252		return;
4253
4254	port_dev = hub->ports[udev->portnum - 1];
4255
4256	if (port_dev->usb3_lpm_u1_permit)
4257		usb_enable_link_state(hcd, udev, USB3_LPM_U1);
4258
4259	if (port_dev->usb3_lpm_u2_permit)
4260		usb_enable_link_state(hcd, udev, USB3_LPM_U2);
4261}
4262EXPORT_SYMBOL_GPL(usb_enable_lpm);
4263
4264/* Grab the bandwidth_mutex before calling usb_enable_lpm() */
4265void usb_unlocked_enable_lpm(struct usb_device *udev)
4266{
4267	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4268
4269	if (!hcd)
4270		return;
4271
4272	mutex_lock(hcd->bandwidth_mutex);
4273	usb_enable_lpm(udev);
4274	mutex_unlock(hcd->bandwidth_mutex);
4275}
4276EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
4277
4278/* usb3 devices use U3 for disabled, make sure remote wakeup is disabled */
4279static void hub_usb3_port_prepare_disable(struct usb_hub *hub,
4280					  struct usb_port *port_dev)
4281{
4282	struct usb_device *udev = port_dev->child;
4283	int ret;
4284
4285	if (udev && udev->port_is_suspended && udev->do_remote_wakeup) {
4286		ret = hub_set_port_link_state(hub, port_dev->portnum,
4287					      USB_SS_PORT_LS_U0);
4288		if (!ret) {
4289			msleep(USB_RESUME_TIMEOUT);
4290			ret = usb_disable_remote_wakeup(udev);
4291		}
4292		if (ret)
4293			dev_warn(&udev->dev,
4294				 "Port disable: can't disable remote wake\n");
4295		udev->do_remote_wakeup = 0;
4296	}
4297}
4298
4299#else	/* CONFIG_PM */
4300
4301#define hub_suspend		NULL
4302#define hub_resume		NULL
4303#define hub_reset_resume	NULL
4304
4305static inline void hub_usb3_port_prepare_disable(struct usb_hub *hub,
4306						 struct usb_port *port_dev) { }
4307
4308int usb_disable_lpm(struct usb_device *udev)
4309{
4310	return 0;
4311}
4312EXPORT_SYMBOL_GPL(usb_disable_lpm);
4313
4314void usb_enable_lpm(struct usb_device *udev) { }
4315EXPORT_SYMBOL_GPL(usb_enable_lpm);
4316
4317int usb_unlocked_disable_lpm(struct usb_device *udev)
4318{
4319	return 0;
4320}
4321EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
4322
4323void usb_unlocked_enable_lpm(struct usb_device *udev) { }
4324EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
4325
4326int usb_disable_ltm(struct usb_device *udev)
4327{
4328	return 0;
4329}
4330EXPORT_SYMBOL_GPL(usb_disable_ltm);
4331
4332void usb_enable_ltm(struct usb_device *udev) { }
4333EXPORT_SYMBOL_GPL(usb_enable_ltm);
4334
4335static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
4336		u16 portstatus, u16 portchange)
4337{
4338	return 0;
4339}
4340
4341#endif	/* CONFIG_PM */
4342
4343/*
4344 * USB-3 does not have a similar link state as USB-2 that will avoid negotiating
4345 * a connection with a plugged-in cable but will signal the host when the cable
4346 * is unplugged. Disable remote wake and set link state to U3 for USB-3 devices
4347 */
4348static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
4349{
4350	struct usb_port *port_dev = hub->ports[port1 - 1];
4351	struct usb_device *hdev = hub->hdev;
4352	int ret = 0;
4353
4354	if (!hub->error) {
4355		if (hub_is_superspeed(hub->hdev)) {
4356			hub_usb3_port_prepare_disable(hub, port_dev);
4357			ret = hub_set_port_link_state(hub, port_dev->portnum,
4358						      USB_SS_PORT_LS_U3);
4359		} else {
4360			ret = usb_clear_port_feature(hdev, port1,
4361					USB_PORT_FEAT_ENABLE);
4362		}
4363	}
4364	if (port_dev->child && set_state)
4365		usb_set_device_state(port_dev->child, USB_STATE_NOTATTACHED);
4366	if (ret && ret != -ENODEV)
4367		dev_err(&port_dev->dev, "cannot disable (err = %d)\n", ret);
4368	return ret;
4369}
4370
4371/*
4372 * usb_port_disable - disable a usb device's upstream port
4373 * @udev: device to disable
4374 * Context: @udev locked, must be able to sleep.
4375 *
4376 * Disables a USB device that isn't in active use.
4377 */
4378int usb_port_disable(struct usb_device *udev)
4379{
4380	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
4381
4382	return hub_port_disable(hub, udev->portnum, 0);
4383}
4384
4385/* USB 2.0 spec, 7.1.7.3 / fig 7-29:
4386 *
4387 * Between connect detection and reset signaling there must be a delay
4388 * of 100ms at least for debounce and power-settling.  The corresponding
4389 * timer shall restart whenever the downstream port detects a disconnect.
4390 *
4391 * Apparently there are some bluetooth and irda-dongles and a number of
4392 * low-speed devices for which this debounce period may last over a second.
4393 * Not covered by the spec - but easy to deal with.
4394 *
4395 * This implementation uses a 1500ms total debounce timeout; if the
4396 * connection isn't stable by then it returns -ETIMEDOUT.  It checks
4397 * every 25ms for transient disconnects.  When the port status has been
4398 * unchanged for 100ms it returns the port status.
4399 */
4400int hub_port_debounce(struct usb_hub *hub, int port1, bool must_be_connected)
4401{
4402	int ret;
4403	u16 portchange, portstatus;
4404	unsigned connection = 0xffff;
4405	int total_time, stable_time = 0;
4406	struct usb_port *port_dev = hub->ports[port1 - 1];
4407
4408	for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
4409		ret = hub_port_status(hub, port1, &portstatus, &portchange);
4410		if (ret < 0)
4411			return ret;
4412
4413		if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
4414		     (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
4415			if (!must_be_connected ||
4416			     (connection == USB_PORT_STAT_CONNECTION))
4417				stable_time += HUB_DEBOUNCE_STEP;
4418			if (stable_time >= HUB_DEBOUNCE_STABLE)
4419				break;
4420		} else {
4421			stable_time = 0;
4422			connection = portstatus & USB_PORT_STAT_CONNECTION;
4423		}
4424
4425		if (portchange & USB_PORT_STAT_C_CONNECTION) {
4426			usb_clear_port_feature(hub->hdev, port1,
4427					USB_PORT_FEAT_C_CONNECTION);
4428		}
4429
4430		if (total_time >= HUB_DEBOUNCE_TIMEOUT)
4431			break;
4432		msleep(HUB_DEBOUNCE_STEP);
4433	}
4434
4435	dev_dbg(&port_dev->dev, "debounce total %dms stable %dms status 0x%x\n",
4436			total_time, stable_time, portstatus);
4437
4438	if (stable_time < HUB_DEBOUNCE_STABLE)
4439		return -ETIMEDOUT;
4440	return portstatus;
4441}
4442
4443void usb_ep0_reinit(struct usb_device *udev)
4444{
4445	usb_disable_endpoint(udev, 0 + USB_DIR_IN, true);
4446	usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true);
4447	usb_enable_endpoint(udev, &udev->ep0, true);
4448}
4449EXPORT_SYMBOL_GPL(usb_ep0_reinit);
4450
4451#define usb_sndaddr0pipe()	(PIPE_CONTROL << 30)
4452#define usb_rcvaddr0pipe()	((PIPE_CONTROL << 30) | USB_DIR_IN)
4453
4454static int hub_set_address(struct usb_device *udev, int devnum)
4455{
4456	int retval;
4457	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4458
4459	/*
4460	 * The host controller will choose the device address,
4461	 * instead of the core having chosen it earlier
4462	 */
4463	if (!hcd->driver->address_device && devnum <= 1)
4464		return -EINVAL;
4465	if (udev->state == USB_STATE_ADDRESS)
4466		return 0;
4467	if (udev->state != USB_STATE_DEFAULT)
4468		return -EINVAL;
4469	if (hcd->driver->address_device)
4470		retval = hcd->driver->address_device(hcd, udev);
4471	else
4472		retval = usb_control_msg(udev, usb_sndaddr0pipe(),
4473				USB_REQ_SET_ADDRESS, 0, devnum, 0,
4474				NULL, 0, USB_CTRL_SET_TIMEOUT);
4475	if (retval == 0) {
4476		update_devnum(udev, devnum);
4477		/* Device now using proper address. */
4478		usb_set_device_state(udev, USB_STATE_ADDRESS);
4479		usb_ep0_reinit(udev);
4480	}
4481	return retval;
4482}
4483
4484/*
4485 * There are reports of USB 3.0 devices that say they support USB 2.0 Link PM
4486 * when they're plugged into a USB 2.0 port, but they don't work when LPM is
4487 * enabled.
4488 *
4489 * Only enable USB 2.0 Link PM if the port is internal (hardwired), or the
4490 * device says it supports the new USB 2.0 Link PM errata by setting the BESL
4491 * support bit in the BOS descriptor.
4492 */
4493static void hub_set_initial_usb2_lpm_policy(struct usb_device *udev)
4494{
4495	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
4496	int connect_type = USB_PORT_CONNECT_TYPE_UNKNOWN;
4497
4498	if (!udev->usb2_hw_lpm_capable || !udev->bos)
4499		return;
4500
4501	if (hub)
4502		connect_type = hub->ports[udev->portnum - 1]->connect_type;
4503
4504	if ((udev->bos->ext_cap->bmAttributes & cpu_to_le32(USB_BESL_SUPPORT)) ||
4505			connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
4506		udev->usb2_hw_lpm_allowed = 1;
4507		usb_enable_usb2_hardware_lpm(udev);
4508	}
4509}
4510
4511static int hub_enable_device(struct usb_device *udev)
4512{
4513	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4514
4515	if (!hcd->driver->enable_device)
4516		return 0;
4517	if (udev->state == USB_STATE_ADDRESS)
4518		return 0;
4519	if (udev->state != USB_STATE_DEFAULT)
4520		return -EINVAL;
4521
4522	return hcd->driver->enable_device(hcd, udev);
4523}
4524
4525/* Reset device, (re)assign address, get device descriptor.
4526 * Device connection must be stable, no more debouncing needed.
4527 * Returns device in USB_STATE_ADDRESS, except on error.
4528 *
4529 * If this is called for an already-existing device (as part of
4530 * usb_reset_and_verify_device), the caller must own the device lock and
4531 * the port lock.  For a newly detected device that is not accessible
4532 * through any global pointers, it's not necessary to lock the device,
4533 * but it is still necessary to lock the port.
4534 */
4535static int
4536hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1,
4537		int retry_counter)
4538{
4539	struct usb_device	*hdev = hub->hdev;
4540	struct usb_hcd		*hcd = bus_to_hcd(hdev->bus);
4541	struct usb_port		*port_dev = hub->ports[port1 - 1];
4542	int			retries, operations, retval, i;
4543	unsigned		delay = HUB_SHORT_RESET_TIME;
4544	enum usb_device_speed	oldspeed = udev->speed;
4545	const char		*speed;
4546	int			devnum = udev->devnum;
4547	const char		*driver_name;
4548
4549	/* root hub ports have a slightly longer reset period
4550	 * (from USB 2.0 spec, section 7.1.7.5)
4551	 */
4552	if (!hdev->parent) {
4553		delay = HUB_ROOT_RESET_TIME;
4554		if (port1 == hdev->bus->otg_port)
4555			hdev->bus->b_hnp_enable = 0;
4556	}
4557
4558	/* Some low speed devices have problems with the quick delay, so */
4559	/*  be a bit pessimistic with those devices. RHbug #23670 */
4560	if (oldspeed == USB_SPEED_LOW)
4561		delay = HUB_LONG_RESET_TIME;
4562
4563	mutex_lock(hcd->address0_mutex);
4564
4565	/* Reset the device; full speed may morph to high speed */
4566	/* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */
4567	retval = hub_port_reset(hub, port1, udev, delay, false);
4568	if (retval < 0)		/* error or disconnect */
4569		goto fail;
4570	/* success, speed is known */
4571
4572	retval = -ENODEV;
4573
4574	/* Don't allow speed changes at reset, except usb 3.0 to faster */
4575	if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed &&
4576	    !(oldspeed == USB_SPEED_SUPER && udev->speed > oldspeed)) {
4577		dev_dbg(&udev->dev, "device reset changed speed!\n");
4578		goto fail;
4579	}
4580	oldspeed = udev->speed;
4581
4582	/* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
4583	 * it's fixed size except for full speed devices.
4584	 * For Wireless USB devices, ep0 max packet is always 512 (tho
4585	 * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
4586	 */
4587	switch (udev->speed) {
4588	case USB_SPEED_SUPER_PLUS:
4589	case USB_SPEED_SUPER:
4590	case USB_SPEED_WIRELESS:	/* fixed at 512 */
4591		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
4592		break;
4593	case USB_SPEED_HIGH:		/* fixed at 64 */
4594		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
4595		break;
4596	case USB_SPEED_FULL:		/* 8, 16, 32, or 64 */
4597		/* to determine the ep0 maxpacket size, try to read
4598		 * the device descriptor to get bMaxPacketSize0 and
4599		 * then correct our initial guess.
4600		 */
4601		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
4602		break;
4603	case USB_SPEED_LOW:		/* fixed at 8 */
4604		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(8);
4605		break;
4606	default:
4607		goto fail;
4608	}
4609
4610	if (udev->speed == USB_SPEED_WIRELESS)
4611		speed = "variable speed Wireless";
4612	else
4613		speed = usb_speed_string(udev->speed);
4614
4615	/*
4616	 * The controller driver may be NULL if the controller device
4617	 * is the middle device between platform device and roothub.
4618	 * This middle device may not need a device driver due to
4619	 * all hardware control can be at platform device driver, this
4620	 * platform device is usually a dual-role USB controller device.
4621	 */
4622	if (udev->bus->controller->driver)
4623		driver_name = udev->bus->controller->driver->name;
4624	else
4625		driver_name = udev->bus->sysdev->driver->name;
4626
4627	if (udev->speed < USB_SPEED_SUPER)
4628		dev_info(&udev->dev,
4629				"%s %s USB device number %d using %s\n",
4630				(udev->config) ? "reset" : "new", speed,
4631				devnum, driver_name);
4632
4633	/* Set up TT records, if needed  */
4634	if (hdev->tt) {
4635		udev->tt = hdev->tt;
4636		udev->ttport = hdev->ttport;
4637	} else if (udev->speed != USB_SPEED_HIGH
4638			&& hdev->speed == USB_SPEED_HIGH) {
4639		if (!hub->tt.hub) {
4640			dev_err(&udev->dev, "parent hub has no TT\n");
4641			retval = -EINVAL;
4642			goto fail;
4643		}
4644		udev->tt = &hub->tt;
4645		udev->ttport = port1;
4646	}
4647
4648	/* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
4649	 * Because device hardware and firmware is sometimes buggy in
4650	 * this area, and this is how Linux has done it for ages.
4651	 * Change it cautiously.
4652	 *
4653	 * NOTE:  If use_new_scheme() is true we will start by issuing
4654	 * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
4655	 * so it may help with some non-standards-compliant devices.
4656	 * Otherwise we start with SET_ADDRESS and then try to read the
4657	 * first 8 bytes of the device descriptor to get the ep0 maxpacket
4658	 * value.
4659	 */
4660	for (retries = 0; retries < GET_DESCRIPTOR_TRIES; (++retries, msleep(100))) {
4661		bool did_new_scheme = false;
4662
4663		if (use_new_scheme(udev, retry_counter, port_dev)) {
4664			struct usb_device_descriptor *buf;
4665			int r = 0;
4666
4667			did_new_scheme = true;
4668			retval = hub_enable_device(udev);
4669			if (retval < 0) {
4670				dev_err(&udev->dev,
4671					"hub failed to enable device, error %d\n",
4672					retval);
4673				goto fail;
4674			}
4675
4676#define GET_DESCRIPTOR_BUFSIZE	64
4677			buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
4678			if (!buf) {
4679				retval = -ENOMEM;
4680				continue;
4681			}
4682
4683			/* Retry on all errors; some devices are flakey.
4684			 * 255 is for WUSB devices, we actually need to use
4685			 * 512 (WUSB1.0[4.8.1]).
4686			 */
4687			for (operations = 0; operations < 3; ++operations) {
4688				buf->bMaxPacketSize0 = 0;
4689				r = usb_control_msg(udev, usb_rcvaddr0pipe(),
4690					USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
4691					USB_DT_DEVICE << 8, 0,
4692					buf, GET_DESCRIPTOR_BUFSIZE,
4693					initial_descriptor_timeout);
4694				switch (buf->bMaxPacketSize0) {
4695				case 8: case 16: case 32: case 64: case 255:
4696					if (buf->bDescriptorType ==
4697							USB_DT_DEVICE) {
4698						r = 0;
4699						break;
4700					}
4701					fallthrough;
4702				default:
4703					if (r == 0)
4704						r = -EPROTO;
4705					break;
4706				}
4707				/*
4708				 * Some devices time out if they are powered on
4709				 * when already connected. They need a second
4710				 * reset. But only on the first attempt,
4711				 * lest we get into a time out/reset loop
4712				 */
4713				if (r == 0 || (r == -ETIMEDOUT &&
4714						retries == 0 &&
4715						udev->speed > USB_SPEED_FULL))
4716					break;
4717			}
4718			udev->descriptor.bMaxPacketSize0 =
4719					buf->bMaxPacketSize0;
4720			kfree(buf);
4721
4722			retval = hub_port_reset(hub, port1, udev, delay, false);
4723			if (retval < 0)		/* error or disconnect */
4724				goto fail;
4725			if (oldspeed != udev->speed) {
4726				dev_dbg(&udev->dev,
4727					"device reset changed speed!\n");
4728				retval = -ENODEV;
4729				goto fail;
4730			}
4731			if (r) {
4732				if (r != -ENODEV)
4733					dev_err(&udev->dev, "device descriptor read/64, error %d\n",
4734							r);
4735				retval = -EMSGSIZE;
4736				continue;
4737			}
4738#undef GET_DESCRIPTOR_BUFSIZE
4739		}
4740
4741		/*
4742		 * If device is WUSB, we already assigned an
4743		 * unauthorized address in the Connect Ack sequence;
4744		 * authorization will assign the final address.
4745		 */
4746		if (udev->wusb == 0) {
4747			for (operations = 0; operations < SET_ADDRESS_TRIES; ++operations) {
4748				retval = hub_set_address(udev, devnum);
4749				if (retval >= 0)
4750					break;
4751				msleep(200);
4752			}
4753			if (retval < 0) {
4754				if (retval != -ENODEV)
4755					dev_err(&udev->dev, "device not accepting address %d, error %d\n",
4756							devnum, retval);
4757				goto fail;
4758			}
4759			if (udev->speed >= USB_SPEED_SUPER) {
4760				devnum = udev->devnum;
4761				dev_info(&udev->dev,
4762						"%s SuperSpeed%s%s USB device number %d using %s\n",
4763						(udev->config) ? "reset" : "new",
4764					 (udev->speed == USB_SPEED_SUPER_PLUS) ?
4765							"Plus Gen 2" : " Gen 1",
4766					 (udev->rx_lanes == 2 && udev->tx_lanes == 2) ?
4767							"x2" : "",
4768					 devnum, driver_name);
4769			}
4770
4771			/* cope with hardware quirkiness:
4772			 *  - let SET_ADDRESS settle, some device hardware wants it
4773			 *  - read ep0 maxpacket even for high and low speed,
4774			 */
4775			msleep(10);
4776			/* use_new_scheme() checks the speed which may have
4777			 * changed since the initial look so we cache the result
4778			 * in did_new_scheme
4779			 */
4780			if (did_new_scheme)
4781				break;
4782		}
4783
4784		retval = usb_get_device_descriptor(udev, 8);
4785		if (retval < 8) {
4786			if (retval != -ENODEV)
4787				dev_err(&udev->dev,
4788					"device descriptor read/8, error %d\n",
4789					retval);
4790			if (retval >= 0)
4791				retval = -EMSGSIZE;
4792		} else {
4793			u32 delay;
4794
4795			retval = 0;
4796
4797			delay = udev->parent->hub_delay;
4798			udev->hub_delay = min_t(u32, delay,
4799						USB_TP_TRANSMISSION_DELAY_MAX);
4800			retval = usb_set_isoch_delay(udev);
4801			if (retval) {
4802				dev_dbg(&udev->dev,
4803					"Failed set isoch delay, error %d\n",
4804					retval);
4805				retval = 0;
4806			}
4807			break;
4808		}
4809	}
4810	if (retval)
4811		goto fail;
4812
4813	/*
4814	 * Some superspeed devices have finished the link training process
4815	 * and attached to a superspeed hub port, but the device descriptor
4816	 * got from those devices show they aren't superspeed devices. Warm
4817	 * reset the port attached by the devices can fix them.
4818	 */
4819	if ((udev->speed >= USB_SPEED_SUPER) &&
4820			(le16_to_cpu(udev->descriptor.bcdUSB) < 0x0300)) {
4821		dev_err(&udev->dev, "got a wrong device descriptor, "
4822				"warm reset device\n");
4823		hub_port_reset(hub, port1, udev,
4824				HUB_BH_RESET_TIME, true);
4825		retval = -EINVAL;
4826		goto fail;
4827	}
4828
4829	if (udev->descriptor.bMaxPacketSize0 == 0xff ||
4830			udev->speed >= USB_SPEED_SUPER)
4831		i = 512;
4832	else
4833		i = udev->descriptor.bMaxPacketSize0;
4834	if (usb_endpoint_maxp(&udev->ep0.desc) != i) {
4835		if (udev->speed == USB_SPEED_LOW ||
4836				!(i == 8 || i == 16 || i == 32 || i == 64)) {
4837			dev_err(&udev->dev, "Invalid ep0 maxpacket: %d\n", i);
4838			retval = -EMSGSIZE;
4839			goto fail;
4840		}
4841		if (udev->speed == USB_SPEED_FULL)
4842			dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
4843		else
4844			dev_warn(&udev->dev, "Using ep0 maxpacket: %d\n", i);
4845		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
4846		usb_ep0_reinit(udev);
4847	}
4848
4849	retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
4850	if (retval < (signed)sizeof(udev->descriptor)) {
4851		if (retval != -ENODEV)
4852			dev_err(&udev->dev, "device descriptor read/all, error %d\n",
4853					retval);
4854		if (retval >= 0)
4855			retval = -ENOMSG;
4856		goto fail;
4857	}
4858
4859	usb_detect_quirks(udev);
4860
4861	if (udev->wusb == 0 && le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0201) {
4862		retval = usb_get_bos_descriptor(udev);
4863		if (!retval) {
4864			udev->lpm_capable = usb_device_supports_lpm(udev);
4865			usb_set_lpm_parameters(udev);
4866		}
4867	}
4868
4869	retval = 0;
4870	/* notify HCD that we have a device connected and addressed */
4871	if (hcd->driver->update_device)
4872		hcd->driver->update_device(hcd, udev);
4873	hub_set_initial_usb2_lpm_policy(udev);
4874fail:
4875	if (retval) {
4876		hub_port_disable(hub, port1, 0);
4877		update_devnum(udev, devnum);	/* for disconnect processing */
4878	}
4879	mutex_unlock(hcd->address0_mutex);
4880	return retval;
4881}
4882
4883static void
4884check_highspeed(struct usb_hub *hub, struct usb_device *udev, int port1)
4885{
4886	struct usb_qualifier_descriptor	*qual;
4887	int				status;
4888
4889	if (udev->quirks & USB_QUIRK_DEVICE_QUALIFIER)
4890		return;
4891
4892	qual = kmalloc(sizeof *qual, GFP_KERNEL);
4893	if (qual == NULL)
4894		return;
4895
4896	status = usb_get_descriptor(udev, USB_DT_DEVICE_QUALIFIER, 0,
4897			qual, sizeof *qual);
4898	if (status == sizeof *qual) {
4899		dev_info(&udev->dev, "not running at top speed; "
4900			"connect to a high speed hub\n");
4901		/* hub LEDs are probably harder to miss than syslog */
4902		if (hub->has_indicators) {
4903			hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
4904			queue_delayed_work(system_power_efficient_wq,
4905					&hub->leds, 0);
4906		}
4907	}
4908	kfree(qual);
4909}
4910
4911static unsigned
4912hub_power_remaining(struct usb_hub *hub)
4913{
4914	struct usb_device *hdev = hub->hdev;
4915	int remaining;
4916	int port1;
4917
4918	if (!hub->limited_power)
4919		return 0;
4920
4921	remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
4922	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
4923		struct usb_port *port_dev = hub->ports[port1 - 1];
4924		struct usb_device *udev = port_dev->child;
4925		unsigned unit_load;
4926		int delta;
4927
4928		if (!udev)
4929			continue;
4930		if (hub_is_superspeed(udev))
4931			unit_load = 150;
4932		else
4933			unit_load = 100;
4934
4935		/*
4936		 * Unconfigured devices may not use more than one unit load,
4937		 * or 8mA for OTG ports
4938		 */
4939		if (udev->actconfig)
4940			delta = usb_get_max_power(udev, udev->actconfig);
4941		else if (port1 != udev->bus->otg_port || hdev->parent)
4942			delta = unit_load;
4943		else
4944			delta = 8;
4945		if (delta > hub->mA_per_port)
4946			dev_warn(&port_dev->dev, "%dmA is over %umA budget!\n",
4947					delta, hub->mA_per_port);
4948		remaining -= delta;
4949	}
4950	if (remaining < 0) {
4951		dev_warn(hub->intfdev, "%dmA over power budget!\n",
4952			-remaining);
4953		remaining = 0;
4954	}
4955	return remaining;
4956}
4957
4958
4959static int descriptors_changed(struct usb_device *udev,
4960		struct usb_device_descriptor *old_device_descriptor,
4961		struct usb_host_bos *old_bos)
4962{
4963	int		changed = 0;
4964	unsigned	index;
4965	unsigned	serial_len = 0;
4966	unsigned	len;
4967	unsigned	old_length;
4968	int		length;
4969	char		*buf;
4970
4971	if (memcmp(&udev->descriptor, old_device_descriptor,
4972			sizeof(*old_device_descriptor)) != 0)
4973		return 1;
4974
4975	if ((old_bos && !udev->bos) || (!old_bos && udev->bos))
4976		return 1;
4977	if (udev->bos) {
4978		len = le16_to_cpu(udev->bos->desc->wTotalLength);
4979		if (len != le16_to_cpu(old_bos->desc->wTotalLength))
4980			return 1;
4981		if (memcmp(udev->bos->desc, old_bos->desc, len))
4982			return 1;
4983	}
4984
4985	/* Since the idVendor, idProduct, and bcdDevice values in the
4986	 * device descriptor haven't changed, we will assume the
4987	 * Manufacturer and Product strings haven't changed either.
4988	 * But the SerialNumber string could be different (e.g., a
4989	 * different flash card of the same brand).
4990	 */
4991	if (udev->serial)
4992		serial_len = strlen(udev->serial) + 1;
4993
4994	len = serial_len;
4995	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
4996		old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
4997		len = max(len, old_length);
4998	}
4999
5000	buf = kmalloc(len, GFP_NOIO);
5001	if (!buf)
5002		/* assume the worst */
5003		return 1;
5004
5005	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
5006		old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
5007		length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
5008				old_length);
5009		if (length != old_length) {
5010			dev_dbg(&udev->dev, "config index %d, error %d\n",
5011					index, length);
5012			changed = 1;
5013			break;
5014		}
5015		if (memcmp(buf, udev->rawdescriptors[index], old_length)
5016				!= 0) {
5017			dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
5018				index,
5019				((struct usb_config_descriptor *) buf)->
5020					bConfigurationValue);
5021			changed = 1;
5022			break;
5023		}
5024	}
5025
5026	if (!changed && serial_len) {
5027		length = usb_string(udev, udev->descriptor.iSerialNumber,
5028				buf, serial_len);
5029		if (length + 1 != serial_len) {
5030			dev_dbg(&udev->dev, "serial string error %d\n",
5031					length);
5032			changed = 1;
5033		} else if (memcmp(buf, udev->serial, length) != 0) {
5034			dev_dbg(&udev->dev, "serial string changed\n");
5035			changed = 1;
5036		}
5037	}
5038
5039	kfree(buf);
5040	return changed;
5041}
5042
5043static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
5044		u16 portchange)
5045{
5046	int status = -ENODEV;
5047	int i;
5048	unsigned unit_load;
5049	struct usb_device *hdev = hub->hdev;
5050	struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
5051	struct usb_port *port_dev = hub->ports[port1 - 1];
5052	struct usb_device *udev = port_dev->child;
5053	static int unreliable_port = -1;
5054
5055	/* Disconnect any existing devices under this port */
5056	if (udev) {
5057		if (hcd->usb_phy && !hdev->parent)
5058			usb_phy_notify_disconnect(hcd->usb_phy, udev->speed);
5059		usb_disconnect(&port_dev->child);
5060	}
5061
5062	/* We can forget about a "removed" device when there's a physical
5063	 * disconnect or the connect status changes.
5064	 */
5065	if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
5066			(portchange & USB_PORT_STAT_C_CONNECTION))
5067		clear_bit(port1, hub->removed_bits);
5068
5069	if (portchange & (USB_PORT_STAT_C_CONNECTION |
5070				USB_PORT_STAT_C_ENABLE)) {
5071		status = hub_port_debounce_be_stable(hub, port1);
5072		if (status < 0) {
5073			if (status != -ENODEV &&
5074				port1 != unreliable_port &&
5075				printk_ratelimit())
5076				dev_err(&port_dev->dev, "connect-debounce failed\n");
5077			portstatus &= ~USB_PORT_STAT_CONNECTION;
5078			unreliable_port = port1;
5079		} else {
5080			portstatus = status;
5081		}
5082	}
5083
5084	/* Return now if debouncing failed or nothing is connected or
5085	 * the device was "removed".
5086	 */
5087	if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
5088			test_bit(port1, hub->removed_bits)) {
5089
5090		/*
5091		 * maybe switch power back on (e.g. root hub was reset)
5092		 * but only if the port isn't owned by someone else.
5093		 */
5094		if (hub_is_port_power_switchable(hub)
5095				&& !port_is_power_on(hub, portstatus)
5096				&& !port_dev->port_owner)
5097			set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
5098
5099		if (portstatus & USB_PORT_STAT_ENABLE)
5100			goto done;
5101		return;
5102	}
5103	if (hub_is_superspeed(hub->hdev))
5104		unit_load = 150;
5105	else
5106		unit_load = 100;
5107
5108	status = 0;
5109	for (i = 0; i < SET_CONFIG_TRIES; i++) {
5110
5111		/* reallocate for each attempt, since references
5112		 * to the previous one can escape in various ways
5113		 */
5114		udev = usb_alloc_dev(hdev, hdev->bus, port1);
5115		if (!udev) {
5116			dev_err(&port_dev->dev,
5117					"couldn't allocate usb_device\n");
5118			goto done;
5119		}
5120
5121		usb_set_device_state(udev, USB_STATE_POWERED);
5122		udev->bus_mA = hub->mA_per_port;
5123		udev->level = hdev->level + 1;
5124		udev->wusb = hub_is_wusb(hub);
5125
5126		/* Devices connected to SuperSpeed hubs are USB 3.0 or later */
5127		if (hub_is_superspeed(hub->hdev))
5128			udev->speed = USB_SPEED_SUPER;
5129		else
5130			udev->speed = USB_SPEED_UNKNOWN;
5131
5132		choose_devnum(udev);
5133		if (udev->devnum <= 0) {
5134			status = -ENOTCONN;	/* Don't retry */
5135			goto loop;
5136		}
5137
5138		/* reset (non-USB 3.0 devices) and get descriptor */
5139		usb_lock_port(port_dev);
5140		status = hub_port_init(hub, udev, port1, i);
5141		usb_unlock_port(port_dev);
5142		if (status < 0)
5143			goto loop;
5144
5145		if (udev->quirks & USB_QUIRK_DELAY_INIT)
5146			msleep(2000);
5147
5148		/* consecutive bus-powered hubs aren't reliable; they can
5149		 * violate the voltage drop budget.  if the new child has
5150		 * a "powered" LED, users should notice we didn't enable it
5151		 * (without reading syslog), even without per-port LEDs
5152		 * on the parent.
5153		 */
5154		if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
5155				&& udev->bus_mA <= unit_load) {
5156			u16	devstat;
5157
5158			status = usb_get_std_status(udev, USB_RECIP_DEVICE, 0,
5159					&devstat);
5160			if (status) {
5161				dev_dbg(&udev->dev, "get status %d ?\n", status);
5162				goto loop_disable;
5163			}
5164			if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
5165				dev_err(&udev->dev,
5166					"can't connect bus-powered hub "
5167					"to this port\n");
5168				if (hub->has_indicators) {
5169					hub->indicator[port1-1] =
5170						INDICATOR_AMBER_BLINK;
5171					queue_delayed_work(
5172						system_power_efficient_wq,
5173						&hub->leds, 0);
5174				}
5175				status = -ENOTCONN;	/* Don't retry */
5176				goto loop_disable;
5177			}
5178		}
5179
5180		/* check for devices running slower than they could */
5181		if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
5182				&& udev->speed == USB_SPEED_FULL
5183				&& highspeed_hubs != 0)
5184			check_highspeed(hub, udev, port1);
5185
5186		/* Store the parent's children[] pointer.  At this point
5187		 * udev becomes globally accessible, although presumably
5188		 * no one will look at it until hdev is unlocked.
5189		 */
5190		status = 0;
5191
5192		mutex_lock(&usb_port_peer_mutex);
5193
5194		/* We mustn't add new devices if the parent hub has
5195		 * been disconnected; we would race with the
5196		 * recursively_mark_NOTATTACHED() routine.
5197		 */
5198		spin_lock_irq(&device_state_lock);
5199		if (hdev->state == USB_STATE_NOTATTACHED)
5200			status = -ENOTCONN;
5201		else
5202			port_dev->child = udev;
5203		spin_unlock_irq(&device_state_lock);
5204		mutex_unlock(&usb_port_peer_mutex);
5205
5206		/* Run it through the hoops (find a driver, etc) */
5207		if (!status) {
5208			status = usb_new_device(udev);
5209			if (status) {
5210				mutex_lock(&usb_port_peer_mutex);
5211				spin_lock_irq(&device_state_lock);
5212				port_dev->child = NULL;
5213				spin_unlock_irq(&device_state_lock);
5214				mutex_unlock(&usb_port_peer_mutex);
5215			} else {
5216				if (hcd->usb_phy && !hdev->parent)
5217					usb_phy_notify_connect(hcd->usb_phy,
5218							udev->speed);
5219			}
5220		}
5221
5222		if (status)
5223			goto loop_disable;
5224
5225		status = hub_power_remaining(hub);
5226		if (status)
5227			dev_dbg(hub->intfdev, "%dmA power budget left\n", status);
5228
5229		return;
5230
5231loop_disable:
5232		hub_port_disable(hub, port1, 1);
5233loop:
5234		usb_ep0_reinit(udev);
5235		release_devnum(udev);
5236		hub_free_dev(udev);
5237		usb_put_dev(udev);
5238		if ((status == -ENOTCONN) || (status == -ENOTSUPP))
5239			break;
5240
5241		/* When halfway through our retry count, power-cycle the port */
5242		if (i == (SET_CONFIG_TRIES / 2) - 1) {
5243			dev_info(&port_dev->dev, "attempt power cycle\n");
5244			usb_hub_set_port_power(hdev, hub, port1, false);
5245			msleep(2 * hub_power_on_good_delay(hub));
5246			usb_hub_set_port_power(hdev, hub, port1, true);
5247			msleep(hub_power_on_good_delay(hub));
5248		}
5249	}
5250	if (hub->hdev->parent ||
5251			!hcd->driver->port_handed_over ||
5252			!(hcd->driver->port_handed_over)(hcd, port1)) {
5253		if (status != -ENOTCONN && status != -ENODEV)
5254			dev_err(&port_dev->dev,
5255					"unable to enumerate USB device\n");
5256	}
5257
5258done:
5259	hub_port_disable(hub, port1, 1);
5260	if (hcd->driver->relinquish_port && !hub->hdev->parent) {
5261		if (status != -ENOTCONN && status != -ENODEV)
5262			hcd->driver->relinquish_port(hcd, port1);
5263	}
5264}
5265
5266/* Handle physical or logical connection change events.
5267 * This routine is called when:
5268 *	a port connection-change occurs;
5269 *	a port enable-change occurs (often caused by EMI);
5270 *	usb_reset_and_verify_device() encounters changed descriptors (as from
5271 *		a firmware download)
5272 * caller already locked the hub
5273 */
5274static void hub_port_connect_change(struct usb_hub *hub, int port1,
5275					u16 portstatus, u16 portchange)
5276		__must_hold(&port_dev->status_lock)
5277{
5278	struct usb_port *port_dev = hub->ports[port1 - 1];
5279	struct usb_device *udev = port_dev->child;
5280	struct usb_device_descriptor descriptor;
5281	int status = -ENODEV;
5282	int retval;
5283
5284	dev_dbg(&port_dev->dev, "status %04x, change %04x, %s\n", portstatus,
5285			portchange, portspeed(hub, portstatus));
5286
5287	if (hub->has_indicators) {
5288		set_port_led(hub, port1, HUB_LED_AUTO);
5289		hub->indicator[port1-1] = INDICATOR_AUTO;
5290	}
5291
5292#ifdef	CONFIG_USB_OTG
5293	/* during HNP, don't repeat the debounce */
5294	if (hub->hdev->bus->is_b_host)
5295		portchange &= ~(USB_PORT_STAT_C_CONNECTION |
5296				USB_PORT_STAT_C_ENABLE);
5297#endif
5298
5299	/* Try to resuscitate an existing device */
5300	if ((portstatus & USB_PORT_STAT_CONNECTION) && udev &&
5301			udev->state != USB_STATE_NOTATTACHED) {
5302		if (portstatus & USB_PORT_STAT_ENABLE) {
5303			/*
5304			 * USB-3 connections are initialized automatically by
5305			 * the hostcontroller hardware. Therefore check for
5306			 * changed device descriptors before resuscitating the
5307			 * device.
5308			 */
5309			descriptor = udev->descriptor;
5310			retval = usb_get_device_descriptor(udev,
5311					sizeof(udev->descriptor));
5312			if (retval < 0) {
5313				dev_dbg(&udev->dev,
5314						"can't read device descriptor %d\n",
5315						retval);
5316			} else {
5317				if (descriptors_changed(udev, &descriptor,
5318						udev->bos)) {
5319					dev_dbg(&udev->dev,
5320							"device descriptor has changed\n");
5321					/* for disconnect() calls */
5322					udev->descriptor = descriptor;
5323				} else {
5324					status = 0; /* Nothing to do */
5325				}
5326			}
5327#ifdef CONFIG_PM
5328		} else if (udev->state == USB_STATE_SUSPENDED &&
5329				udev->persist_enabled) {
5330			/* For a suspended device, treat this as a
5331			 * remote wakeup event.
5332			 */
5333			usb_unlock_port(port_dev);
5334			status = usb_remote_wakeup(udev);
5335			usb_lock_port(port_dev);
5336#endif
5337		} else {
5338			/* Don't resuscitate */;
5339		}
5340	}
5341	clear_bit(port1, hub->change_bits);
5342
5343	/* successfully revalidated the connection */
5344	if (status == 0)
5345		return;
5346
5347	usb_unlock_port(port_dev);
5348	hub_port_connect(hub, port1, portstatus, portchange);
5349	usb_lock_port(port_dev);
5350}
5351
5352/* Handle notifying userspace about hub over-current events */
5353static void port_over_current_notify(struct usb_port *port_dev)
5354{
5355	char *envp[3];
5356	struct device *hub_dev;
5357	char *port_dev_path;
5358
5359	sysfs_notify(&port_dev->dev.kobj, NULL, "over_current_count");
5360
5361	hub_dev = port_dev->dev.parent;
5362
5363	if (!hub_dev)
5364		return;
5365
5366	port_dev_path = kobject_get_path(&port_dev->dev.kobj, GFP_KERNEL);
5367	if (!port_dev_path)
5368		return;
5369
5370	envp[0] = kasprintf(GFP_KERNEL, "OVER_CURRENT_PORT=%s", port_dev_path);
5371	if (!envp[0])
5372		goto exit_path;
5373
5374	envp[1] = kasprintf(GFP_KERNEL, "OVER_CURRENT_COUNT=%u",
5375			port_dev->over_current_count);
5376	if (!envp[1])
5377		goto exit;
5378
5379	envp[2] = NULL;
5380	kobject_uevent_env(&hub_dev->kobj, KOBJ_CHANGE, envp);
5381
5382	kfree(envp[1]);
5383exit:
5384	kfree(envp[0]);
5385exit_path:
5386	kfree(port_dev_path);
5387}
5388
5389static void port_event(struct usb_hub *hub, int port1)
5390		__must_hold(&port_dev->status_lock)
5391{
5392	int connect_change;
5393	struct usb_port *port_dev = hub->ports[port1 - 1];
5394	struct usb_device *udev = port_dev->child;
5395	struct usb_device *hdev = hub->hdev;
5396	u16 portstatus, portchange;
5397
5398	connect_change = test_bit(port1, hub->change_bits);
5399	clear_bit(port1, hub->event_bits);
5400	clear_bit(port1, hub->wakeup_bits);
5401
5402	if (hub_port_status(hub, port1, &portstatus, &portchange) < 0)
5403		return;
5404
5405	if (portchange & USB_PORT_STAT_C_CONNECTION) {
5406		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
5407		connect_change = 1;
5408	}
5409
5410	if (portchange & USB_PORT_STAT_C_ENABLE) {
5411		if (!connect_change)
5412			dev_dbg(&port_dev->dev, "enable change, status %08x\n",
5413					portstatus);
5414		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
5415
5416		/*
5417		 * EM interference sometimes causes badly shielded USB devices
5418		 * to be shutdown by the hub, this hack enables them again.
5419		 * Works at least with mouse driver.
5420		 */
5421		if (!(portstatus & USB_PORT_STAT_ENABLE)
5422		    && !connect_change && udev) {
5423			dev_err(&port_dev->dev, "disabled by hub (EMI?), re-enabling...\n");
5424			connect_change = 1;
5425		}
5426	}
5427
5428	if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
5429		u16 status = 0, unused;
5430		port_dev->over_current_count++;
5431		port_over_current_notify(port_dev);
5432
5433		dev_dbg(&port_dev->dev, "over-current change #%u\n",
5434			port_dev->over_current_count);
5435		usb_clear_port_feature(hdev, port1,
5436				USB_PORT_FEAT_C_OVER_CURRENT);
5437		msleep(100);	/* Cool down */
5438		hub_power_on(hub, true);
5439		hub_port_status(hub, port1, &status, &unused);
5440		if (status & USB_PORT_STAT_OVERCURRENT)
5441			dev_err(&port_dev->dev, "over-current condition\n");
5442	}
5443
5444	if (portchange & USB_PORT_STAT_C_RESET) {
5445		dev_dbg(&port_dev->dev, "reset change\n");
5446		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_RESET);
5447	}
5448	if ((portchange & USB_PORT_STAT_C_BH_RESET)
5449	    && hub_is_superspeed(hdev)) {
5450		dev_dbg(&port_dev->dev, "warm reset change\n");
5451		usb_clear_port_feature(hdev, port1,
5452				USB_PORT_FEAT_C_BH_PORT_RESET);
5453	}
5454	if (portchange & USB_PORT_STAT_C_LINK_STATE) {
5455		dev_dbg(&port_dev->dev, "link state change\n");
5456		usb_clear_port_feature(hdev, port1,
5457				USB_PORT_FEAT_C_PORT_LINK_STATE);
5458	}
5459	if (portchange & USB_PORT_STAT_C_CONFIG_ERROR) {
5460		dev_warn(&port_dev->dev, "config error\n");
5461		usb_clear_port_feature(hdev, port1,
5462				USB_PORT_FEAT_C_PORT_CONFIG_ERROR);
5463	}
5464
5465	/* skip port actions that require the port to be powered on */
5466	if (!pm_runtime_active(&port_dev->dev))
5467		return;
5468
5469	if (hub_handle_remote_wakeup(hub, port1, portstatus, portchange))
5470		connect_change = 1;
5471
5472	/*
5473	 * Warm reset a USB3 protocol port if it's in
5474	 * SS.Inactive state.
5475	 */
5476	if (hub_port_warm_reset_required(hub, port1, portstatus)) {
5477		dev_dbg(&port_dev->dev, "do warm reset\n");
5478		if (!udev || !(portstatus & USB_PORT_STAT_CONNECTION)
5479				|| udev->state == USB_STATE_NOTATTACHED) {
5480			if (hub_port_reset(hub, port1, NULL,
5481					HUB_BH_RESET_TIME, true) < 0)
5482				hub_port_disable(hub, port1, 1);
5483		} else {
5484			usb_unlock_port(port_dev);
5485			usb_lock_device(udev);
5486			usb_reset_device(udev);
5487			usb_unlock_device(udev);
5488			usb_lock_port(port_dev);
5489			connect_change = 0;
5490		}
5491	}
5492
5493	if (connect_change)
5494		hub_port_connect_change(hub, port1, portstatus, portchange);
5495}
5496
5497static void hub_event(struct work_struct *work)
5498{
5499	struct usb_device *hdev;
5500	struct usb_interface *intf;
5501	struct usb_hub *hub;
5502	struct device *hub_dev;
5503	u16 hubstatus;
5504	u16 hubchange;
5505	int i, ret;
5506
5507	hub = container_of(work, struct usb_hub, events);
5508	hdev = hub->hdev;
5509	hub_dev = hub->intfdev;
5510	intf = to_usb_interface(hub_dev);
5511
5512	kcov_remote_start_usb((u64)hdev->bus->busnum);
5513
5514	dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
5515			hdev->state, hdev->maxchild,
5516			/* NOTE: expects max 15 ports... */
5517			(u16) hub->change_bits[0],
5518			(u16) hub->event_bits[0]);
5519
5520	/* Lock the device, then check to see if we were
5521	 * disconnected while waiting for the lock to succeed. */
5522	usb_lock_device(hdev);
5523	if (unlikely(hub->disconnected))
5524		goto out_hdev_lock;
5525
5526	/* If the hub has died, clean up after it */
5527	if (hdev->state == USB_STATE_NOTATTACHED) {
5528		hub->error = -ENODEV;
5529		hub_quiesce(hub, HUB_DISCONNECT);
5530		goto out_hdev_lock;
5531	}
5532
5533	/* Autoresume */
5534	ret = usb_autopm_get_interface(intf);
5535	if (ret) {
5536		dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
5537		goto out_hdev_lock;
5538	}
5539
5540	/* If this is an inactive hub, do nothing */
5541	if (hub->quiescing)
5542		goto out_autopm;
5543
5544	if (hub->error) {
5545		dev_dbg(hub_dev, "resetting for error %d\n", hub->error);
5546
5547		ret = usb_reset_device(hdev);
5548		if (ret) {
5549			dev_dbg(hub_dev, "error resetting hub: %d\n", ret);
5550			goto out_autopm;
5551		}
5552
5553		hub->nerrors = 0;
5554		hub->error = 0;
5555	}
5556
5557	/* deal with port status changes */
5558	for (i = 1; i <= hdev->maxchild; i++) {
5559		struct usb_port *port_dev = hub->ports[i - 1];
5560
5561		if (test_bit(i, hub->event_bits)
5562				|| test_bit(i, hub->change_bits)
5563				|| test_bit(i, hub->wakeup_bits)) {
5564			/*
5565			 * The get_noresume and barrier ensure that if
5566			 * the port was in the process of resuming, we
5567			 * flush that work and keep the port active for
5568			 * the duration of the port_event().  However,
5569			 * if the port is runtime pm suspended
5570			 * (powered-off), we leave it in that state, run
5571			 * an abbreviated port_event(), and move on.
5572			 */
5573			pm_runtime_get_noresume(&port_dev->dev);
5574			pm_runtime_barrier(&port_dev->dev);
5575			usb_lock_port(port_dev);
5576			port_event(hub, i);
5577			usb_unlock_port(port_dev);
5578			pm_runtime_put_sync(&port_dev->dev);
5579		}
5580	}
5581
5582	/* deal with hub status changes */
5583	if (test_and_clear_bit(0, hub->event_bits) == 0)
5584		;	/* do nothing */
5585	else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
5586		dev_err(hub_dev, "get_hub_status failed\n");
5587	else {
5588		if (hubchange & HUB_CHANGE_LOCAL_POWER) {
5589			dev_dbg(hub_dev, "power change\n");
5590			clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
5591			if (hubstatus & HUB_STATUS_LOCAL_POWER)
5592				/* FIXME: Is this always true? */
5593				hub->limited_power = 1;
5594			else
5595				hub->limited_power = 0;
5596		}
5597		if (hubchange & HUB_CHANGE_OVERCURRENT) {
5598			u16 status = 0;
5599			u16 unused;
5600
5601			dev_dbg(hub_dev, "over-current change\n");
5602			clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
5603			msleep(500);	/* Cool down */
5604			hub_power_on(hub, true);
5605			hub_hub_status(hub, &status, &unused);
5606			if (status & HUB_STATUS_OVERCURRENT)
5607				dev_err(hub_dev, "over-current condition\n");
5608		}
5609	}
5610
5611out_autopm:
5612	/* Balance the usb_autopm_get_interface() above */
5613	usb_autopm_put_interface_no_suspend(intf);
5614out_hdev_lock:
5615	usb_unlock_device(hdev);
5616
5617	/* Balance the stuff in kick_hub_wq() and allow autosuspend */
5618	usb_autopm_put_interface(intf);
5619	kref_put(&hub->kref, hub_release);
5620
5621	kcov_remote_stop();
5622}
5623
5624static const struct usb_device_id hub_id_table[] = {
5625    { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5626                   | USB_DEVICE_ID_MATCH_PRODUCT
5627                   | USB_DEVICE_ID_MATCH_INT_CLASS,
5628      .idVendor = USB_VENDOR_SMSC,
5629      .idProduct = USB_PRODUCT_USB5534B,
5630      .bInterfaceClass = USB_CLASS_HUB,
5631      .driver_info = HUB_QUIRK_DISABLE_AUTOSUSPEND},
5632    { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5633			| USB_DEVICE_ID_MATCH_INT_CLASS,
5634      .idVendor = USB_VENDOR_GENESYS_LOGIC,
5635      .bInterfaceClass = USB_CLASS_HUB,
5636      .driver_info = HUB_QUIRK_CHECK_PORT_AUTOSUSPEND},
5637    { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
5638      .bDeviceClass = USB_CLASS_HUB},
5639    { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
5640      .bInterfaceClass = USB_CLASS_HUB},
5641    { }						/* Terminating entry */
5642};
5643
5644MODULE_DEVICE_TABLE(usb, hub_id_table);
5645
5646static struct usb_driver hub_driver = {
5647	.name =		"hub",
5648	.probe =	hub_probe,
5649	.disconnect =	hub_disconnect,
5650	.suspend =	hub_suspend,
5651	.resume =	hub_resume,
5652	.reset_resume =	hub_reset_resume,
5653	.pre_reset =	hub_pre_reset,
5654	.post_reset =	hub_post_reset,
5655	.unlocked_ioctl = hub_ioctl,
5656	.id_table =	hub_id_table,
5657	.supports_autosuspend =	1,
5658};
5659
5660int usb_hub_init(void)
5661{
5662	if (usb_register(&hub_driver) < 0) {
5663		printk(KERN_ERR "%s: can't register hub driver\n",
5664			usbcore_name);
5665		return -1;
5666	}
5667
5668	/*
5669	 * The workqueue needs to be freezable to avoid interfering with
5670	 * USB-PERSIST port handover. Otherwise it might see that a full-speed
5671	 * device was gone before the EHCI controller had handed its port
5672	 * over to the companion full-speed controller.
5673	 */
5674	hub_wq = alloc_workqueue("usb_hub_wq", WQ_FREEZABLE, 0);
5675	if (hub_wq)
5676		return 0;
5677
5678	/* Fall through if kernel_thread failed */
5679	usb_deregister(&hub_driver);
5680	pr_err("%s: can't allocate workqueue for usb hub\n", usbcore_name);
5681
5682	return -1;
5683}
5684
5685void usb_hub_cleanup(void)
5686{
5687	destroy_workqueue(hub_wq);
5688
5689	/*
5690	 * Hub resources are freed for us by usb_deregister. It calls
5691	 * usb_driver_purge on every device which in turn calls that
5692	 * devices disconnect function if it is using this driver.
5693	 * The hub_disconnect function takes care of releasing the
5694	 * individual hub resources. -greg
5695	 */
5696	usb_deregister(&hub_driver);
5697} /* usb_hub_cleanup() */
5698
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5699/**
5700 * usb_reset_and_verify_device - perform a USB port reset to reinitialize a device
5701 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
5702 *
5703 * WARNING - don't use this routine to reset a composite device
5704 * (one with multiple interfaces owned by separate drivers)!
5705 * Use usb_reset_device() instead.
5706 *
5707 * Do a port reset, reassign the device's address, and establish its
5708 * former operating configuration.  If the reset fails, or the device's
5709 * descriptors change from their values before the reset, or the original
5710 * configuration and altsettings cannot be restored, a flag will be set
5711 * telling hub_wq to pretend the device has been disconnected and then
5712 * re-connected.  All drivers will be unbound, and the device will be
5713 * re-enumerated and probed all over again.
5714 *
5715 * Return: 0 if the reset succeeded, -ENODEV if the device has been
5716 * flagged for logical disconnection, or some other negative error code
5717 * if the reset wasn't even attempted.
5718 *
5719 * Note:
5720 * The caller must own the device lock and the port lock, the latter is
5721 * taken by usb_reset_device().  For example, it's safe to use
5722 * usb_reset_device() from a driver probe() routine after downloading
5723 * new firmware.  For calls that might not occur during probe(), drivers
5724 * should lock the device using usb_lock_device_for_reset().
5725 *
5726 * Locking exception: This routine may also be called from within an
5727 * autoresume handler.  Such usage won't conflict with other tasks
5728 * holding the device lock because these tasks should always call
5729 * usb_autopm_resume_device(), thereby preventing any unwanted
5730 * autoresume.  The autoresume handler is expected to have already
5731 * acquired the port lock before calling this routine.
5732 */
5733static int usb_reset_and_verify_device(struct usb_device *udev)
5734{
5735	struct usb_device		*parent_hdev = udev->parent;
5736	struct usb_hub			*parent_hub;
5737	struct usb_hcd			*hcd = bus_to_hcd(udev->bus);
5738	struct usb_device_descriptor	descriptor = udev->descriptor;
5739	struct usb_host_bos		*bos;
5740	int				i, j, ret = 0;
5741	int				port1 = udev->portnum;
5742
5743	if (udev->state == USB_STATE_NOTATTACHED ||
5744			udev->state == USB_STATE_SUSPENDED) {
5745		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
5746				udev->state);
5747		return -EINVAL;
5748	}
5749
5750	if (!parent_hdev)
5751		return -EISDIR;
5752
5753	parent_hub = usb_hub_to_struct_hub(parent_hdev);
5754
5755	/* Disable USB2 hardware LPM.
5756	 * It will be re-enabled by the enumeration process.
5757	 */
5758	usb_disable_usb2_hardware_lpm(udev);
5759
5760	/* Disable LPM while we reset the device and reinstall the alt settings.
5761	 * Device-initiated LPM, and system exit latency settings are cleared
5762	 * when the device is reset, so we have to set them up again.
5763	 */
5764	ret = usb_unlocked_disable_lpm(udev);
5765	if (ret) {
5766		dev_err(&udev->dev, "%s Failed to disable LPM\n", __func__);
5767		goto re_enumerate_no_bos;
5768	}
5769
5770	bos = udev->bos;
5771	udev->bos = NULL;
5772
5773	for (i = 0; i < SET_CONFIG_TRIES; ++i) {
5774
5775		/* ep0 maxpacket size may change; let the HCD know about it.
5776		 * Other endpoints will be handled by re-enumeration. */
5777		usb_ep0_reinit(udev);
5778		ret = hub_port_init(parent_hub, udev, port1, i);
5779		if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
5780			break;
5781	}
5782
5783	if (ret < 0)
5784		goto re_enumerate;
5785
5786	/* Device might have changed firmware (DFU or similar) */
5787	if (descriptors_changed(udev, &descriptor, bos)) {
5788		dev_info(&udev->dev, "device firmware changed\n");
5789		udev->descriptor = descriptor;	/* for disconnect() calls */
5790		goto re_enumerate;
5791	}
5792
5793	/* Restore the device's previous configuration */
5794	if (!udev->actconfig)
5795		goto done;
5796
5797	mutex_lock(hcd->bandwidth_mutex);
5798	ret = usb_hcd_alloc_bandwidth(udev, udev->actconfig, NULL, NULL);
5799	if (ret < 0) {
5800		dev_warn(&udev->dev,
5801				"Busted HC?  Not enough HCD resources for "
5802				"old configuration.\n");
5803		mutex_unlock(hcd->bandwidth_mutex);
5804		goto re_enumerate;
5805	}
5806	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
5807			USB_REQ_SET_CONFIGURATION, 0,
5808			udev->actconfig->desc.bConfigurationValue, 0,
5809			NULL, 0, USB_CTRL_SET_TIMEOUT);
5810	if (ret < 0) {
5811		dev_err(&udev->dev,
5812			"can't restore configuration #%d (error=%d)\n",
5813			udev->actconfig->desc.bConfigurationValue, ret);
5814		mutex_unlock(hcd->bandwidth_mutex);
5815		goto re_enumerate;
5816	}
5817	mutex_unlock(hcd->bandwidth_mutex);
5818	usb_set_device_state(udev, USB_STATE_CONFIGURED);
5819
5820	/* Put interfaces back into the same altsettings as before.
5821	 * Don't bother to send the Set-Interface request for interfaces
5822	 * that were already in altsetting 0; besides being unnecessary,
5823	 * many devices can't handle it.  Instead just reset the host-side
5824	 * endpoint state.
5825	 */
5826	for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
5827		struct usb_host_config *config = udev->actconfig;
5828		struct usb_interface *intf = config->interface[i];
5829		struct usb_interface_descriptor *desc;
5830
5831		desc = &intf->cur_altsetting->desc;
5832		if (desc->bAlternateSetting == 0) {
5833			usb_disable_interface(udev, intf, true);
5834			usb_enable_interface(udev, intf, true);
5835			ret = 0;
5836		} else {
5837			/* Let the bandwidth allocation function know that this
5838			 * device has been reset, and it will have to use
5839			 * alternate setting 0 as the current alternate setting.
5840			 */
5841			intf->resetting_device = 1;
5842			ret = usb_set_interface(udev, desc->bInterfaceNumber,
5843					desc->bAlternateSetting);
5844			intf->resetting_device = 0;
5845		}
5846		if (ret < 0) {
5847			dev_err(&udev->dev, "failed to restore interface %d "
5848				"altsetting %d (error=%d)\n",
5849				desc->bInterfaceNumber,
5850				desc->bAlternateSetting,
5851				ret);
5852			goto re_enumerate;
5853		}
5854		/* Resetting also frees any allocated streams */
5855		for (j = 0; j < intf->cur_altsetting->desc.bNumEndpoints; j++)
5856			intf->cur_altsetting->endpoint[j].streams = 0;
5857	}
5858
5859done:
5860	/* Now that the alt settings are re-installed, enable LTM and LPM. */
5861	usb_enable_usb2_hardware_lpm(udev);
5862	usb_unlocked_enable_lpm(udev);
5863	usb_enable_ltm(udev);
5864	usb_release_bos_descriptor(udev);
5865	udev->bos = bos;
5866	return 0;
5867
5868re_enumerate:
5869	usb_release_bos_descriptor(udev);
5870	udev->bos = bos;
5871re_enumerate_no_bos:
5872	/* LPM state doesn't matter when we're about to destroy the device. */
5873	hub_port_logical_disconnect(parent_hub, port1);
5874	return -ENODEV;
5875}
5876
5877/**
5878 * usb_reset_device - warn interface drivers and perform a USB port reset
5879 * @udev: device to reset (not in NOTATTACHED state)
5880 *
5881 * Warns all drivers bound to registered interfaces (using their pre_reset
5882 * method), performs the port reset, and then lets the drivers know that
5883 * the reset is over (using their post_reset method).
5884 *
5885 * Return: The same as for usb_reset_and_verify_device().
5886 *
5887 * Note:
5888 * The caller must own the device lock.  For example, it's safe to use
5889 * this from a driver probe() routine after downloading new firmware.
5890 * For calls that might not occur during probe(), drivers should lock
5891 * the device using usb_lock_device_for_reset().
5892 *
5893 * If an interface is currently being probed or disconnected, we assume
5894 * its driver knows how to handle resets.  For all other interfaces,
5895 * if the driver doesn't have pre_reset and post_reset methods then
5896 * we attempt to unbind it and rebind afterward.
5897 */
5898int usb_reset_device(struct usb_device *udev)
5899{
5900	int ret;
5901	int i;
5902	unsigned int noio_flag;
5903	struct usb_port *port_dev;
5904	struct usb_host_config *config = udev->actconfig;
5905	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
5906
5907	if (udev->state == USB_STATE_NOTATTACHED) {
 
5908		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
5909				udev->state);
5910		return -EINVAL;
5911	}
5912
5913	if (!udev->parent) {
5914		/* this requires hcd-specific logic; see ohci_restart() */
5915		dev_dbg(&udev->dev, "%s for root hub!\n", __func__);
5916		return -EISDIR;
5917	}
5918
5919	port_dev = hub->ports[udev->portnum - 1];
5920
5921	/*
5922	 * Don't allocate memory with GFP_KERNEL in current
5923	 * context to avoid possible deadlock if usb mass
5924	 * storage interface or usbnet interface(iSCSI case)
5925	 * is included in current configuration. The easist
5926	 * approach is to do it for every device reset,
5927	 * because the device 'memalloc_noio' flag may have
5928	 * not been set before reseting the usb device.
5929	 */
5930	noio_flag = memalloc_noio_save();
5931
5932	/* Prevent autosuspend during the reset */
5933	usb_autoresume_device(udev);
5934
5935	if (config) {
5936		for (i = 0; i < config->desc.bNumInterfaces; ++i) {
5937			struct usb_interface *cintf = config->interface[i];
5938			struct usb_driver *drv;
5939			int unbind = 0;
5940
5941			if (cintf->dev.driver) {
5942				drv = to_usb_driver(cintf->dev.driver);
5943				if (drv->pre_reset && drv->post_reset)
5944					unbind = (drv->pre_reset)(cintf);
5945				else if (cintf->condition ==
5946						USB_INTERFACE_BOUND)
5947					unbind = 1;
5948				if (unbind)
5949					usb_forced_unbind_intf(cintf);
5950			}
5951		}
5952	}
5953
5954	usb_lock_port(port_dev);
5955	ret = usb_reset_and_verify_device(udev);
5956	usb_unlock_port(port_dev);
5957
5958	if (config) {
5959		for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
5960			struct usb_interface *cintf = config->interface[i];
5961			struct usb_driver *drv;
5962			int rebind = cintf->needs_binding;
5963
5964			if (!rebind && cintf->dev.driver) {
5965				drv = to_usb_driver(cintf->dev.driver);
5966				if (drv->post_reset)
5967					rebind = (drv->post_reset)(cintf);
5968				else if (cintf->condition ==
5969						USB_INTERFACE_BOUND)
5970					rebind = 1;
5971				if (rebind)
5972					cintf->needs_binding = 1;
5973			}
5974		}
5975
5976		/* If the reset failed, hub_wq will unbind drivers later */
5977		if (ret == 0)
5978			usb_unbind_and_rebind_marked_interfaces(udev);
5979	}
5980
5981	usb_autosuspend_device(udev);
5982	memalloc_noio_restore(noio_flag);
5983	return ret;
5984}
5985EXPORT_SYMBOL_GPL(usb_reset_device);
5986
5987
5988/**
5989 * usb_queue_reset_device - Reset a USB device from an atomic context
5990 * @iface: USB interface belonging to the device to reset
5991 *
5992 * This function can be used to reset a USB device from an atomic
5993 * context, where usb_reset_device() won't work (as it blocks).
5994 *
5995 * Doing a reset via this method is functionally equivalent to calling
5996 * usb_reset_device(), except for the fact that it is delayed to a
5997 * workqueue. This means that any drivers bound to other interfaces
5998 * might be unbound, as well as users from usbfs in user space.
5999 *
6000 * Corner cases:
6001 *
6002 * - Scheduling two resets at the same time from two different drivers
6003 *   attached to two different interfaces of the same device is
6004 *   possible; depending on how the driver attached to each interface
6005 *   handles ->pre_reset(), the second reset might happen or not.
6006 *
6007 * - If the reset is delayed so long that the interface is unbound from
6008 *   its driver, the reset will be skipped.
6009 *
6010 * - This function can be called during .probe().  It can also be called
6011 *   during .disconnect(), but doing so is pointless because the reset
6012 *   will not occur.  If you really want to reset the device during
6013 *   .disconnect(), call usb_reset_device() directly -- but watch out
6014 *   for nested unbinding issues!
6015 */
6016void usb_queue_reset_device(struct usb_interface *iface)
6017{
6018	if (schedule_work(&iface->reset_ws))
6019		usb_get_intf(iface);
6020}
6021EXPORT_SYMBOL_GPL(usb_queue_reset_device);
6022
6023/**
6024 * usb_hub_find_child - Get the pointer of child device
6025 * attached to the port which is specified by @port1.
6026 * @hdev: USB device belonging to the usb hub
6027 * @port1: port num to indicate which port the child device
6028 *	is attached to.
6029 *
6030 * USB drivers call this function to get hub's child device
6031 * pointer.
6032 *
6033 * Return: %NULL if input param is invalid and
6034 * child's usb_device pointer if non-NULL.
6035 */
6036struct usb_device *usb_hub_find_child(struct usb_device *hdev,
6037		int port1)
6038{
6039	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
6040
6041	if (port1 < 1 || port1 > hdev->maxchild)
6042		return NULL;
6043	return hub->ports[port1 - 1]->child;
6044}
6045EXPORT_SYMBOL_GPL(usb_hub_find_child);
6046
6047void usb_hub_adjust_deviceremovable(struct usb_device *hdev,
6048		struct usb_hub_descriptor *desc)
6049{
6050	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
6051	enum usb_port_connect_type connect_type;
6052	int i;
6053
6054	if (!hub)
6055		return;
6056
6057	if (!hub_is_superspeed(hdev)) {
6058		for (i = 1; i <= hdev->maxchild; i++) {
6059			struct usb_port *port_dev = hub->ports[i - 1];
6060
6061			connect_type = port_dev->connect_type;
6062			if (connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
6063				u8 mask = 1 << (i%8);
6064
6065				if (!(desc->u.hs.DeviceRemovable[i/8] & mask)) {
6066					dev_dbg(&port_dev->dev, "DeviceRemovable is changed to 1 according to platform information.\n");
6067					desc->u.hs.DeviceRemovable[i/8]	|= mask;
6068				}
6069			}
6070		}
6071	} else {
6072		u16 port_removable = le16_to_cpu(desc->u.ss.DeviceRemovable);
6073
6074		for (i = 1; i <= hdev->maxchild; i++) {
6075			struct usb_port *port_dev = hub->ports[i - 1];
6076
6077			connect_type = port_dev->connect_type;
6078			if (connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
6079				u16 mask = 1 << i;
6080
6081				if (!(port_removable & mask)) {
6082					dev_dbg(&port_dev->dev, "DeviceRemovable is changed to 1 according to platform information.\n");
6083					port_removable |= mask;
6084				}
6085			}
6086		}
6087
6088		desc->u.ss.DeviceRemovable = cpu_to_le16(port_removable);
6089	}
6090}
6091
6092#ifdef CONFIG_ACPI
6093/**
6094 * usb_get_hub_port_acpi_handle - Get the usb port's acpi handle
6095 * @hdev: USB device belonging to the usb hub
6096 * @port1: port num of the port
6097 *
6098 * Return: Port's acpi handle if successful, %NULL if params are
6099 * invalid.
6100 */
6101acpi_handle usb_get_hub_port_acpi_handle(struct usb_device *hdev,
6102	int port1)
6103{
6104	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
6105
6106	if (!hub)
6107		return NULL;
6108
6109	return ACPI_HANDLE(&hub->ports[port1 - 1]->dev);
6110}
6111#endif