1/*
   2 * USB hub driver.
   3 *
   4 * (C) Copyright 1999 Linus Torvalds
   5 * (C) Copyright 1999 Johannes Erdfelt
   6 * (C) Copyright 1999 Gregory P. Smith
   7 * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
   8 *
 
 
   9 */
  10
  11#include <linux/kernel.h>
  12#include <linux/errno.h>
  13#include <linux/module.h>
  14#include <linux/moduleparam.h>
  15#include <linux/completion.h>
  16#include <linux/sched.h>
  17#include <linux/list.h>
  18#include <linux/slab.h>
  19#include <linux/ioctl.h>
  20#include <linux/usb.h>
  21#include <linux/usbdevice_fs.h>
  22#include <linux/usb/hcd.h>
  23#include <linux/usb/otg.h>
  24#include <linux/usb/quirks.h>
  25#include <linux/workqueue.h>
  26#include <linux/mutex.h>
  27#include <linux/random.h>
  28#include <linux/pm_qos.h>
  29
  30#include <asm/uaccess.h>
  31#include <asm/byteorder.h>
  32
  33#include "hub.h"
  34#include "otg_whitelist.h"
  35
  36#define USB_VENDOR_GENESYS_LOGIC		0x05e3
  37#define HUB_QUIRK_CHECK_PORT_AUTOSUSPEND	0x01
  38
  39/* Protect struct usb_device->state and ->children members
  40 * Note: Both are also protected by ->dev.sem, except that ->state can
  41 * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
  42static DEFINE_SPINLOCK(device_state_lock);
  43
  44/* workqueue to process hub events */
  45static struct workqueue_struct *hub_wq;
  46static void hub_event(struct work_struct *work);
  47
  48/* synchronize hub-port add/remove and peering operations */
  49DEFINE_MUTEX(usb_port_peer_mutex);
  50
  51/* cycle leds on hubs that aren't blinking for attention */
  52static bool blinkenlights;
  53module_param(blinkenlights, bool, S_IRUGO);
  54MODULE_PARM_DESC(blinkenlights, "true to cycle leds on hubs");
  55
  56/*
  57 * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
  58 * 10 seconds to send reply for the initial 64-byte descriptor request.
  59 */
  60/* define initial 64-byte descriptor request timeout in milliseconds */
  61static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
  62module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
  63MODULE_PARM_DESC(initial_descriptor_timeout,
  64		"initial 64-byte descriptor request timeout in milliseconds "
  65		"(default 5000 - 5.0 seconds)");
  66
  67/*
  68 * As of 2.6.10 we introduce a new USB device initialization scheme which
  69 * closely resembles the way Windows works.  Hopefully it will be compatible
  70 * with a wider range of devices than the old scheme.  However some previously
  71 * working devices may start giving rise to "device not accepting address"
  72 * errors; if that happens the user can try the old scheme by adjusting the
  73 * following module parameters.
  74 *
  75 * For maximum flexibility there are two boolean parameters to control the
  76 * hub driver's behavior.  On the first initialization attempt, if the
  77 * "old_scheme_first" parameter is set then the old scheme will be used,
  78 * otherwise the new scheme is used.  If that fails and "use_both_schemes"
  79 * is set, then the driver will make another attempt, using the other scheme.
  80 */
  81static bool old_scheme_first;
  82module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
  83MODULE_PARM_DESC(old_scheme_first,
  84		 "start with the old device initialization scheme");
  85
  86static bool use_both_schemes = 1;
  87module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
  88MODULE_PARM_DESC(use_both_schemes,
  89		"try the other device initialization scheme if the "
  90		"first one fails");
  91
  92/* Mutual exclusion for EHCI CF initialization.  This interferes with
  93 * port reset on some companion controllers.
  94 */
  95DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
  96EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
  97
  98#define HUB_DEBOUNCE_TIMEOUT	2000
  99#define HUB_DEBOUNCE_STEP	  25
 100#define HUB_DEBOUNCE_STABLE	 100
 101
 102static void hub_release(struct kref *kref);
 103static int usb_reset_and_verify_device(struct usb_device *udev);
 
 104
 105static inline char *portspeed(struct usb_hub *hub, int portstatus)
 106{
 
 
 107	if (hub_is_superspeed(hub->hdev))
 108		return "5.0 Gb/s";
 109	if (portstatus & USB_PORT_STAT_HIGH_SPEED)
 110		return "480 Mb/s";
 111	else if (portstatus & USB_PORT_STAT_LOW_SPEED)
 112		return "1.5 Mb/s";
 113	else
 114		return "12 Mb/s";
 115}
 116
 117/* Note that hdev or one of its children must be locked! */
 118struct usb_hub *usb_hub_to_struct_hub(struct usb_device *hdev)
 119{
 120	if (!hdev || !hdev->actconfig || !hdev->maxchild)
 121		return NULL;
 122	return usb_get_intfdata(hdev->actconfig->interface[0]);
 123}
 124
 125int usb_device_supports_lpm(struct usb_device *udev)
 126{
 127	/* Some devices have trouble with LPM */
 128	if (udev->quirks & USB_QUIRK_NO_LPM)
 129		return 0;
 130
 131	/* USB 2.1 (and greater) devices indicate LPM support through
 132	 * their USB 2.0 Extended Capabilities BOS descriptor.
 133	 */
 134	if (udev->speed == USB_SPEED_HIGH || udev->speed == USB_SPEED_FULL) {
 135		if (udev->bos->ext_cap &&
 136			(USB_LPM_SUPPORT &
 137			 le32_to_cpu(udev->bos->ext_cap->bmAttributes)))
 138			return 1;
 139		return 0;
 140	}
 141
 142	/*
 143	 * According to the USB 3.0 spec, all USB 3.0 devices must support LPM.
 144	 * However, there are some that don't, and they set the U1/U2 exit
 145	 * latencies to zero.
 146	 */
 147	if (!udev->bos->ss_cap) {
 148		dev_info(&udev->dev, "No LPM exit latency info found, disabling LPM.\n");
 149		return 0;
 150	}
 151
 152	if (udev->bos->ss_cap->bU1devExitLat == 0 &&
 153			udev->bos->ss_cap->bU2DevExitLat == 0) {
 154		if (udev->parent)
 155			dev_info(&udev->dev, "LPM exit latency is zeroed, disabling LPM.\n");
 156		else
 157			dev_info(&udev->dev, "We don't know the algorithms for LPM for this host, disabling LPM.\n");
 158		return 0;
 159	}
 160
 161	if (!udev->parent || udev->parent->lpm_capable)
 162		return 1;
 163	return 0;
 164}
 165
 166/*
 167 * Set the Maximum Exit Latency (MEL) for the host to initiate a transition from
 168 * either U1 or U2.
 169 */
 170static void usb_set_lpm_mel(struct usb_device *udev,
 171		struct usb3_lpm_parameters *udev_lpm_params,
 172		unsigned int udev_exit_latency,
 173		struct usb_hub *hub,
 174		struct usb3_lpm_parameters *hub_lpm_params,
 175		unsigned int hub_exit_latency)
 176{
 177	unsigned int total_mel;
 178	unsigned int device_mel;
 179	unsigned int hub_mel;
 180
 181	/*
 182	 * Calculate the time it takes to transition all links from the roothub
 183	 * to the parent hub into U0.  The parent hub must then decode the
 184	 * packet (hub header decode latency) to figure out which port it was
 185	 * bound for.
 186	 *
 187	 * The Hub Header decode latency is expressed in 0.1us intervals (0x1
 188	 * means 0.1us).  Multiply that by 100 to get nanoseconds.
 189	 */
 190	total_mel = hub_lpm_params->mel +
 191		(hub->descriptor->u.ss.bHubHdrDecLat * 100);
 192
 193	/*
 194	 * How long will it take to transition the downstream hub's port into
 195	 * U0?  The greater of either the hub exit latency or the device exit
 196	 * latency.
 197	 *
 198	 * The BOS U1/U2 exit latencies are expressed in 1us intervals.
 199	 * Multiply that by 1000 to get nanoseconds.
 200	 */
 201	device_mel = udev_exit_latency * 1000;
 202	hub_mel = hub_exit_latency * 1000;
 203	if (device_mel > hub_mel)
 204		total_mel += device_mel;
 205	else
 206		total_mel += hub_mel;
 207
 208	udev_lpm_params->mel = total_mel;
 209}
 210
 211/*
 212 * Set the maximum Device to Host Exit Latency (PEL) for the device to initiate
 213 * a transition from either U1 or U2.
 214 */
 215static void usb_set_lpm_pel(struct usb_device *udev,
 216		struct usb3_lpm_parameters *udev_lpm_params,
 217		unsigned int udev_exit_latency,
 218		struct usb_hub *hub,
 219		struct usb3_lpm_parameters *hub_lpm_params,
 220		unsigned int hub_exit_latency,
 221		unsigned int port_to_port_exit_latency)
 222{
 223	unsigned int first_link_pel;
 224	unsigned int hub_pel;
 225
 226	/*
 227	 * First, the device sends an LFPS to transition the link between the
 228	 * device and the parent hub into U0.  The exit latency is the bigger of
 229	 * the device exit latency or the hub exit latency.
 230	 */
 231	if (udev_exit_latency > hub_exit_latency)
 232		first_link_pel = udev_exit_latency * 1000;
 233	else
 234		first_link_pel = hub_exit_latency * 1000;
 235
 236	/*
 237	 * When the hub starts to receive the LFPS, there is a slight delay for
 238	 * it to figure out that one of the ports is sending an LFPS.  Then it
 239	 * will forward the LFPS to its upstream link.  The exit latency is the
 240	 * delay, plus the PEL that we calculated for this hub.
 241	 */
 242	hub_pel = port_to_port_exit_latency * 1000 + hub_lpm_params->pel;
 243
 244	/*
 245	 * According to figure C-7 in the USB 3.0 spec, the PEL for this device
 246	 * is the greater of the two exit latencies.
 247	 */
 248	if (first_link_pel > hub_pel)
 249		udev_lpm_params->pel = first_link_pel;
 250	else
 251		udev_lpm_params->pel = hub_pel;
 252}
 253
 254/*
 255 * Set the System Exit Latency (SEL) to indicate the total worst-case time from
 256 * when a device initiates a transition to U0, until when it will receive the
 257 * first packet from the host controller.
 258 *
 259 * Section C.1.5.1 describes the four components to this:
 260 *  - t1: device PEL
 261 *  - t2: time for the ERDY to make it from the device to the host.
 262 *  - t3: a host-specific delay to process the ERDY.
 263 *  - t4: time for the packet to make it from the host to the device.
 264 *
 265 * t3 is specific to both the xHCI host and the platform the host is integrated
 266 * into.  The Intel HW folks have said it's negligible, FIXME if a different
 267 * vendor says otherwise.
 268 */
 269static void usb_set_lpm_sel(struct usb_device *udev,
 270		struct usb3_lpm_parameters *udev_lpm_params)
 271{
 272	struct usb_device *parent;
 273	unsigned int num_hubs;
 274	unsigned int total_sel;
 275
 276	/* t1 = device PEL */
 277	total_sel = udev_lpm_params->pel;
 278	/* How many external hubs are in between the device & the root port. */
 279	for (parent = udev->parent, num_hubs = 0; parent->parent;
 280			parent = parent->parent)
 281		num_hubs++;
 282	/* t2 = 2.1us + 250ns * (num_hubs - 1) */
 283	if (num_hubs > 0)
 284		total_sel += 2100 + 250 * (num_hubs - 1);
 285
 286	/* t4 = 250ns * num_hubs */
 287	total_sel += 250 * num_hubs;
 288
 289	udev_lpm_params->sel = total_sel;
 290}
 291
 292static void usb_set_lpm_parameters(struct usb_device *udev)
 293{
 294	struct usb_hub *hub;
 295	unsigned int port_to_port_delay;
 296	unsigned int udev_u1_del;
 297	unsigned int udev_u2_del;
 298	unsigned int hub_u1_del;
 299	unsigned int hub_u2_del;
 300
 301	if (!udev->lpm_capable || udev->speed < USB_SPEED_SUPER)
 302		return;
 303
 304	hub = usb_hub_to_struct_hub(udev->parent);
 305	/* It doesn't take time to transition the roothub into U0, since it
 306	 * doesn't have an upstream link.
 307	 */
 308	if (!hub)
 309		return;
 310
 311	udev_u1_del = udev->bos->ss_cap->bU1devExitLat;
 312	udev_u2_del = le16_to_cpu(udev->bos->ss_cap->bU2DevExitLat);
 313	hub_u1_del = udev->parent->bos->ss_cap->bU1devExitLat;
 314	hub_u2_del = le16_to_cpu(udev->parent->bos->ss_cap->bU2DevExitLat);
 315
 316	usb_set_lpm_mel(udev, &udev->u1_params, udev_u1_del,
 317			hub, &udev->parent->u1_params, hub_u1_del);
 318
 319	usb_set_lpm_mel(udev, &udev->u2_params, udev_u2_del,
 320			hub, &udev->parent->u2_params, hub_u2_del);
 321
 322	/*
 323	 * Appendix C, section C.2.2.2, says that there is a slight delay from
 324	 * when the parent hub notices the downstream port is trying to
 325	 * transition to U0 to when the hub initiates a U0 transition on its
 326	 * upstream port.  The section says the delays are tPort2PortU1EL and
 327	 * tPort2PortU2EL, but it doesn't define what they are.
 328	 *
 329	 * The hub chapter, sections 10.4.2.4 and 10.4.2.5 seem to be talking
 330	 * about the same delays.  Use the maximum delay calculations from those
 331	 * sections.  For U1, it's tHubPort2PortExitLat, which is 1us max.  For
 332	 * U2, it's tHubPort2PortExitLat + U2DevExitLat - U1DevExitLat.  I
 333	 * assume the device exit latencies they are talking about are the hub
 334	 * exit latencies.
 335	 *
 336	 * What do we do if the U2 exit latency is less than the U1 exit
 337	 * latency?  It's possible, although not likely...
 338	 */
 339	port_to_port_delay = 1;
 340
 341	usb_set_lpm_pel(udev, &udev->u1_params, udev_u1_del,
 342			hub, &udev->parent->u1_params, hub_u1_del,
 343			port_to_port_delay);
 344
 345	if (hub_u2_del > hub_u1_del)
 346		port_to_port_delay = 1 + hub_u2_del - hub_u1_del;
 347	else
 348		port_to_port_delay = 1 + hub_u1_del;
 349
 350	usb_set_lpm_pel(udev, &udev->u2_params, udev_u2_del,
 351			hub, &udev->parent->u2_params, hub_u2_del,
 352			port_to_port_delay);
 353
 354	/* Now that we've got PEL, calculate SEL. */
 355	usb_set_lpm_sel(udev, &udev->u1_params);
 356	usb_set_lpm_sel(udev, &udev->u2_params);
 357}
 358
 359/* USB 2.0 spec Section 11.24.4.5 */
 360static int get_hub_descriptor(struct usb_device *hdev, void *data)
 361{
 362	int i, ret, size;
 363	unsigned dtype;
 364
 365	if (hub_is_superspeed(hdev)) {
 366		dtype = USB_DT_SS_HUB;
 367		size = USB_DT_SS_HUB_SIZE;
 368	} else {
 369		dtype = USB_DT_HUB;
 370		size = sizeof(struct usb_hub_descriptor);
 371	}
 372
 373	for (i = 0; i < 3; i++) {
 374		ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 375			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
 376			dtype << 8, 0, data, size,
 377			USB_CTRL_GET_TIMEOUT);
 378		if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
 379			return ret;
 380	}
 381	return -EINVAL;
 382}
 383
 384/*
 385 * USB 2.0 spec Section 11.24.2.1
 386 */
 387static int clear_hub_feature(struct usb_device *hdev, int feature)
 388{
 389	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 390		USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
 391}
 392
 393/*
 394 * USB 2.0 spec Section 11.24.2.2
 395 */
 396int usb_clear_port_feature(struct usb_device *hdev, int port1, int feature)
 397{
 398	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 399		USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
 400		NULL, 0, 1000);
 401}
 402
 403/*
 404 * USB 2.0 spec Section 11.24.2.13
 405 */
 406static int set_port_feature(struct usb_device *hdev, int port1, int feature)
 407{
 408	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 409		USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
 410		NULL, 0, 1000);
 411}
 412
 413static char *to_led_name(int selector)
 414{
 415	switch (selector) {
 416	case HUB_LED_AMBER:
 417		return "amber";
 418	case HUB_LED_GREEN:
 419		return "green";
 420	case HUB_LED_OFF:
 421		return "off";
 422	case HUB_LED_AUTO:
 423		return "auto";
 424	default:
 425		return "??";
 426	}
 427}
 428
 429/*
 430 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
 431 * for info about using port indicators
 432 */
 433static void set_port_led(struct usb_hub *hub, int port1, int selector)
 434{
 435	struct usb_port *port_dev = hub->ports[port1 - 1];
 436	int status;
 437
 438	status = set_port_feature(hub->hdev, (selector << 8) | port1,
 439			USB_PORT_FEAT_INDICATOR);
 440	dev_dbg(&port_dev->dev, "indicator %s status %d\n",
 441		to_led_name(selector), status);
 442}
 443
 444#define	LED_CYCLE_PERIOD	((2*HZ)/3)
 445
 446static void led_work(struct work_struct *work)
 447{
 448	struct usb_hub		*hub =
 449		container_of(work, struct usb_hub, leds.work);
 450	struct usb_device	*hdev = hub->hdev;
 451	unsigned		i;
 452	unsigned		changed = 0;
 453	int			cursor = -1;
 454
 455	if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
 456		return;
 457
 458	for (i = 0; i < hdev->maxchild; i++) {
 459		unsigned	selector, mode;
 460
 461		/* 30%-50% duty cycle */
 462
 463		switch (hub->indicator[i]) {
 464		/* cycle marker */
 465		case INDICATOR_CYCLE:
 466			cursor = i;
 467			selector = HUB_LED_AUTO;
 468			mode = INDICATOR_AUTO;
 469			break;
 470		/* blinking green = sw attention */
 471		case INDICATOR_GREEN_BLINK:
 472			selector = HUB_LED_GREEN;
 473			mode = INDICATOR_GREEN_BLINK_OFF;
 474			break;
 475		case INDICATOR_GREEN_BLINK_OFF:
 476			selector = HUB_LED_OFF;
 477			mode = INDICATOR_GREEN_BLINK;
 478			break;
 479		/* blinking amber = hw attention */
 480		case INDICATOR_AMBER_BLINK:
 481			selector = HUB_LED_AMBER;
 482			mode = INDICATOR_AMBER_BLINK_OFF;
 483			break;
 484		case INDICATOR_AMBER_BLINK_OFF:
 485			selector = HUB_LED_OFF;
 486			mode = INDICATOR_AMBER_BLINK;
 487			break;
 488		/* blink green/amber = reserved */
 489		case INDICATOR_ALT_BLINK:
 490			selector = HUB_LED_GREEN;
 491			mode = INDICATOR_ALT_BLINK_OFF;
 492			break;
 493		case INDICATOR_ALT_BLINK_OFF:
 494			selector = HUB_LED_AMBER;
 495			mode = INDICATOR_ALT_BLINK;
 496			break;
 497		default:
 498			continue;
 499		}
 500		if (selector != HUB_LED_AUTO)
 501			changed = 1;
 502		set_port_led(hub, i + 1, selector);
 503		hub->indicator[i] = mode;
 504	}
 505	if (!changed && blinkenlights) {
 506		cursor++;
 507		cursor %= hdev->maxchild;
 508		set_port_led(hub, cursor + 1, HUB_LED_GREEN);
 509		hub->indicator[cursor] = INDICATOR_CYCLE;
 510		changed++;
 511	}
 512	if (changed)
 513		queue_delayed_work(system_power_efficient_wq,
 514				&hub->leds, LED_CYCLE_PERIOD);
 515}
 516
 517/* use a short timeout for hub/port status fetches */
 518#define	USB_STS_TIMEOUT		1000
 519#define	USB_STS_RETRIES		5
 520
 521/*
 522 * USB 2.0 spec Section 11.24.2.6
 523 */
 524static int get_hub_status(struct usb_device *hdev,
 525		struct usb_hub_status *data)
 526{
 527	int i, status = -ETIMEDOUT;
 528
 529	for (i = 0; i < USB_STS_RETRIES &&
 530			(status == -ETIMEDOUT || status == -EPIPE); i++) {
 531		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 532			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
 533			data, sizeof(*data), USB_STS_TIMEOUT);
 534	}
 535	return status;
 536}
 537
 538/*
 539 * USB 2.0 spec Section 11.24.2.7
 540 * USB 3.1 takes into use the wValue and wLength fields, spec Section 10.16.2.6
 541 */
 542static int get_port_status(struct usb_device *hdev, int port1,
 543			   void *data, u16 value, u16 length)
 544{
 545	int i, status = -ETIMEDOUT;
 546
 547	for (i = 0; i < USB_STS_RETRIES &&
 548			(status == -ETIMEDOUT || status == -EPIPE); i++) {
 549		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 550			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, value,
 551			port1, data, length, USB_STS_TIMEOUT);
 552	}
 553	return status;
 554}
 555
 556static int hub_ext_port_status(struct usb_hub *hub, int port1, int type,
 557			       u16 *status, u16 *change, u32 *ext_status)
 558{
 559	int ret;
 560	int len = 4;
 561
 562	if (type != HUB_PORT_STATUS)
 563		len = 8;
 564
 565	mutex_lock(&hub->status_mutex);
 566	ret = get_port_status(hub->hdev, port1, &hub->status->port, type, len);
 567	if (ret < len) {
 568		if (ret != -ENODEV)
 569			dev_err(hub->intfdev,
 570				"%s failed (err = %d)\n", __func__, ret);
 571		if (ret >= 0)
 572			ret = -EIO;
 573	} else {
 574		*status = le16_to_cpu(hub->status->port.wPortStatus);
 575		*change = le16_to_cpu(hub->status->port.wPortChange);
 576		if (type != HUB_PORT_STATUS && ext_status)
 577			*ext_status = le32_to_cpu(
 578				hub->status->port.dwExtPortStatus);
 579		ret = 0;
 580	}
 581	mutex_unlock(&hub->status_mutex);
 582	return ret;
 583}
 584
 585static int hub_port_status(struct usb_hub *hub, int port1,
 586		u16 *status, u16 *change)
 587{
 588	return hub_ext_port_status(hub, port1, HUB_PORT_STATUS,
 589				   status, change, NULL);
 590}
 591
 592static void kick_hub_wq(struct usb_hub *hub)
 593{
 594	struct usb_interface *intf;
 595
 596	if (hub->disconnected || work_pending(&hub->events))
 597		return;
 598
 599	/*
 600	 * Suppress autosuspend until the event is proceed.
 601	 *
 602	 * Be careful and make sure that the symmetric operation is
 603	 * always called. We are here only when there is no pending
 604	 * work for this hub. Therefore put the interface either when
 605	 * the new work is called or when it is canceled.
 606	 */
 607	intf = to_usb_interface(hub->intfdev);
 608	usb_autopm_get_interface_no_resume(intf);
 609	kref_get(&hub->kref);
 610
 611	if (queue_work(hub_wq, &hub->events))
 612		return;
 613
 614	/* the work has already been scheduled */
 615	usb_autopm_put_interface_async(intf);
 616	kref_put(&hub->kref, hub_release);
 617}
 618
 619void usb_kick_hub_wq(struct usb_device *hdev)
 620{
 621	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
 622
 623	if (hub)
 624		kick_hub_wq(hub);
 625}
 626
 627/*
 628 * Let the USB core know that a USB 3.0 device has sent a Function Wake Device
 629 * Notification, which indicates it had initiated remote wakeup.
 630 *
 631 * USB 3.0 hubs do not report the port link state change from U3 to U0 when the
 632 * device initiates resume, so the USB core will not receive notice of the
 633 * resume through the normal hub interrupt URB.
 634 */
 635void usb_wakeup_notification(struct usb_device *hdev,
 636		unsigned int portnum)
 637{
 638	struct usb_hub *hub;
 639
 640	if (!hdev)
 641		return;
 642
 643	hub = usb_hub_to_struct_hub(hdev);
 644	if (hub) {
 645		set_bit(portnum, hub->wakeup_bits);
 646		kick_hub_wq(hub);
 647	}
 648}
 649EXPORT_SYMBOL_GPL(usb_wakeup_notification);
 650
 651/* completion function, fires on port status changes and various faults */
 652static void hub_irq(struct urb *urb)
 653{
 654	struct usb_hub *hub = urb->context;
 655	int status = urb->status;
 656	unsigned i;
 657	unsigned long bits;
 658
 659	switch (status) {
 660	case -ENOENT:		/* synchronous unlink */
 661	case -ECONNRESET:	/* async unlink */
 662	case -ESHUTDOWN:	/* hardware going away */
 663		return;
 664
 665	default:		/* presumably an error */
 666		/* Cause a hub reset after 10 consecutive errors */
 667		dev_dbg(hub->intfdev, "transfer --> %d\n", status);
 668		if ((++hub->nerrors < 10) || hub->error)
 669			goto resubmit;
 670		hub->error = status;
 671		/* FALL THROUGH */
 672
 673	/* let hub_wq handle things */
 674	case 0:			/* we got data:  port status changed */
 675		bits = 0;
 676		for (i = 0; i < urb->actual_length; ++i)
 677			bits |= ((unsigned long) ((*hub->buffer)[i]))
 678					<< (i*8);
 679		hub->event_bits[0] = bits;
 680		break;
 681	}
 682
 683	hub->nerrors = 0;
 684
 685	/* Something happened, let hub_wq figure it out */
 686	kick_hub_wq(hub);
 687
 688resubmit:
 689	if (hub->quiescing)
 690		return;
 691
 692	status = usb_submit_urb(hub->urb, GFP_ATOMIC);
 693	if (status != 0 && status != -ENODEV && status != -EPERM)
 694		dev_err(hub->intfdev, "resubmit --> %d\n", status);
 695}
 696
 697/* USB 2.0 spec Section 11.24.2.3 */
 698static inline int
 699hub_clear_tt_buffer(struct usb_device *hdev, u16 devinfo, u16 tt)
 700{
 701	/* Need to clear both directions for control ep */
 702	if (((devinfo >> 11) & USB_ENDPOINT_XFERTYPE_MASK) ==
 703			USB_ENDPOINT_XFER_CONTROL) {
 704		int status = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 705				HUB_CLEAR_TT_BUFFER, USB_RT_PORT,
 706				devinfo ^ 0x8000, tt, NULL, 0, 1000);
 707		if (status)
 708			return status;
 709	}
 710	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 711			       HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
 712			       tt, NULL, 0, 1000);
 713}
 714
 715/*
 716 * enumeration blocks hub_wq for a long time. we use keventd instead, since
 717 * long blocking there is the exception, not the rule.  accordingly, HCDs
 718 * talking to TTs must queue control transfers (not just bulk and iso), so
 719 * both can talk to the same hub concurrently.
 720 */
 721static void hub_tt_work(struct work_struct *work)
 722{
 723	struct usb_hub		*hub =
 724		container_of(work, struct usb_hub, tt.clear_work);
 725	unsigned long		flags;
 726
 727	spin_lock_irqsave(&hub->tt.lock, flags);
 728	while (!list_empty(&hub->tt.clear_list)) {
 729		struct list_head	*next;
 730		struct usb_tt_clear	*clear;
 731		struct usb_device	*hdev = hub->hdev;
 732		const struct hc_driver	*drv;
 733		int			status;
 734
 735		next = hub->tt.clear_list.next;
 736		clear = list_entry(next, struct usb_tt_clear, clear_list);
 737		list_del(&clear->clear_list);
 738
 739		/* drop lock so HCD can concurrently report other TT errors */
 740		spin_unlock_irqrestore(&hub->tt.lock, flags);
 741		status = hub_clear_tt_buffer(hdev, clear->devinfo, clear->tt);
 742		if (status && status != -ENODEV)
 743			dev_err(&hdev->dev,
 744				"clear tt %d (%04x) error %d\n",
 745				clear->tt, clear->devinfo, status);
 746
 747		/* Tell the HCD, even if the operation failed */
 748		drv = clear->hcd->driver;
 749		if (drv->clear_tt_buffer_complete)
 750			(drv->clear_tt_buffer_complete)(clear->hcd, clear->ep);
 751
 752		kfree(clear);
 753		spin_lock_irqsave(&hub->tt.lock, flags);
 754	}
 755	spin_unlock_irqrestore(&hub->tt.lock, flags);
 756}
 757
 758/**
 759 * usb_hub_set_port_power - control hub port's power state
 760 * @hdev: USB device belonging to the usb hub
 761 * @hub: target hub
 762 * @port1: port index
 763 * @set: expected status
 764 *
 765 * call this function to control port's power via setting or
 766 * clearing the port's PORT_POWER feature.
 767 *
 768 * Return: 0 if successful. A negative error code otherwise.
 769 */
 770int usb_hub_set_port_power(struct usb_device *hdev, struct usb_hub *hub,
 771			   int port1, bool set)
 772{
 773	int ret;
 774
 775	if (set)
 776		ret = set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
 777	else
 778		ret = usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
 779
 780	if (ret)
 781		return ret;
 782
 783	if (set)
 784		set_bit(port1, hub->power_bits);
 785	else
 786		clear_bit(port1, hub->power_bits);
 787	return 0;
 788}
 789
 790/**
 791 * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
 792 * @urb: an URB associated with the failed or incomplete split transaction
 793 *
 794 * High speed HCDs use this to tell the hub driver that some split control or
 795 * bulk transaction failed in a way that requires clearing internal state of
 796 * a transaction translator.  This is normally detected (and reported) from
 797 * interrupt context.
 798 *
 799 * It may not be possible for that hub to handle additional full (or low)
 800 * speed transactions until that state is fully cleared out.
 801 *
 802 * Return: 0 if successful. A negative error code otherwise.
 803 */
 804int usb_hub_clear_tt_buffer(struct urb *urb)
 805{
 806	struct usb_device	*udev = urb->dev;
 807	int			pipe = urb->pipe;
 808	struct usb_tt		*tt = udev->tt;
 809	unsigned long		flags;
 810	struct usb_tt_clear	*clear;
 811
 812	/* we've got to cope with an arbitrary number of pending TT clears,
 813	 * since each TT has "at least two" buffers that can need it (and
 814	 * there can be many TTs per hub).  even if they're uncommon.
 815	 */
 816	clear = kmalloc(sizeof *clear, GFP_ATOMIC);
 817	if (clear == NULL) {
 818		dev_err(&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
 819		/* FIXME recover somehow ... RESET_TT? */
 820		return -ENOMEM;
 821	}
 822
 823	/* info that CLEAR_TT_BUFFER needs */
 824	clear->tt = tt->multi ? udev->ttport : 1;
 825	clear->devinfo = usb_pipeendpoint (pipe);
 826	clear->devinfo |= udev->devnum << 4;
 827	clear->devinfo |= usb_pipecontrol(pipe)
 828			? (USB_ENDPOINT_XFER_CONTROL << 11)
 829			: (USB_ENDPOINT_XFER_BULK << 11);
 830	if (usb_pipein(pipe))
 831		clear->devinfo |= 1 << 15;
 832
 833	/* info for completion callback */
 834	clear->hcd = bus_to_hcd(udev->bus);
 835	clear->ep = urb->ep;
 836
 837	/* tell keventd to clear state for this TT */
 838	spin_lock_irqsave(&tt->lock, flags);
 839	list_add_tail(&clear->clear_list, &tt->clear_list);
 840	schedule_work(&tt->clear_work);
 841	spin_unlock_irqrestore(&tt->lock, flags);
 842	return 0;
 843}
 844EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer);
 845
 846static void hub_power_on(struct usb_hub *hub, bool do_delay)
 847{
 848	int port1;
 849
 850	/* Enable power on each port.  Some hubs have reserved values
 851	 * of LPSM (> 2) in their descriptors, even though they are
 852	 * USB 2.0 hubs.  Some hubs do not implement port-power switching
 853	 * but only emulate it.  In all cases, the ports won't work
 854	 * unless we send these messages to the hub.
 855	 */
 856	if (hub_is_port_power_switchable(hub))
 857		dev_dbg(hub->intfdev, "enabling power on all ports\n");
 858	else
 859		dev_dbg(hub->intfdev, "trying to enable port power on "
 860				"non-switchable hub\n");
 861	for (port1 = 1; port1 <= hub->hdev->maxchild; port1++)
 862		if (test_bit(port1, hub->power_bits))
 863			set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
 864		else
 865			usb_clear_port_feature(hub->hdev, port1,
 866						USB_PORT_FEAT_POWER);
 867	if (do_delay)
 868		msleep(hub_power_on_good_delay(hub));
 869}
 870
 871static int hub_hub_status(struct usb_hub *hub,
 872		u16 *status, u16 *change)
 873{
 874	int ret;
 875
 876	mutex_lock(&hub->status_mutex);
 877	ret = get_hub_status(hub->hdev, &hub->status->hub);
 878	if (ret < 0) {
 879		if (ret != -ENODEV)
 880			dev_err(hub->intfdev,
 881				"%s failed (err = %d)\n", __func__, ret);
 882	} else {
 883		*status = le16_to_cpu(hub->status->hub.wHubStatus);
 884		*change = le16_to_cpu(hub->status->hub.wHubChange);
 885		ret = 0;
 886	}
 887	mutex_unlock(&hub->status_mutex);
 888	return ret;
 889}
 890
 891static int hub_set_port_link_state(struct usb_hub *hub, int port1,
 892			unsigned int link_status)
 893{
 894	return set_port_feature(hub->hdev,
 895			port1 | (link_status << 3),
 896			USB_PORT_FEAT_LINK_STATE);
 897}
 898
 899/*
 900 * If USB 3.0 ports are placed into the Disabled state, they will no longer
 901 * detect any device connects or disconnects.  This is generally not what the
 902 * USB core wants, since it expects a disabled port to produce a port status
 903 * change event when a new device connects.
 904 *
 905 * Instead, set the link state to Disabled, wait for the link to settle into
 906 * that state, clear any change bits, and then put the port into the RxDetect
 907 * state.
 908 */
 909static int hub_usb3_port_disable(struct usb_hub *hub, int port1)
 910{
 911	int ret;
 912	int total_time;
 913	u16 portchange, portstatus;
 914
 915	if (!hub_is_superspeed(hub->hdev))
 916		return -EINVAL;
 917
 918	ret = hub_port_status(hub, port1, &portstatus, &portchange);
 919	if (ret < 0)
 920		return ret;
 921
 922	/*
 923	 * USB controller Advanced Micro Devices, Inc. [AMD] FCH USB XHCI
 924	 * Controller [1022:7814] will have spurious result making the following
 925	 * usb 3.0 device hotplugging route to the 2.0 root hub and recognized
 926	 * as high-speed device if we set the usb 3.0 port link state to
 927	 * Disabled. Since it's already in USB_SS_PORT_LS_RX_DETECT state, we
 928	 * check the state here to avoid the bug.
 929	 */
 930	if ((portstatus & USB_PORT_STAT_LINK_STATE) ==
 931				USB_SS_PORT_LS_RX_DETECT) {
 932		dev_dbg(&hub->ports[port1 - 1]->dev,
 933			 "Not disabling port; link state is RxDetect\n");
 934		return ret;
 935	}
 936
 937	ret = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_SS_DISABLED);
 938	if (ret)
 939		return ret;
 940
 941	/* Wait for the link to enter the disabled state. */
 942	for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
 943		ret = hub_port_status(hub, port1, &portstatus, &portchange);
 944		if (ret < 0)
 945			return ret;
 946
 947		if ((portstatus & USB_PORT_STAT_LINK_STATE) ==
 948				USB_SS_PORT_LS_SS_DISABLED)
 949			break;
 950		if (total_time >= HUB_DEBOUNCE_TIMEOUT)
 951			break;
 952		msleep(HUB_DEBOUNCE_STEP);
 953	}
 954	if (total_time >= HUB_DEBOUNCE_TIMEOUT)
 955		dev_warn(&hub->ports[port1 - 1]->dev,
 956				"Could not disable after %d ms\n", total_time);
 957
 958	return hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_RX_DETECT);
 959}
 960
 961static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
 962{
 963	struct usb_port *port_dev = hub->ports[port1 - 1];
 964	struct usb_device *hdev = hub->hdev;
 965	int ret = 0;
 966
 967	if (port_dev->child && set_state)
 968		usb_set_device_state(port_dev->child, USB_STATE_NOTATTACHED);
 969	if (!hub->error) {
 970		if (hub_is_superspeed(hub->hdev))
 971			ret = hub_usb3_port_disable(hub, port1);
 972		else
 973			ret = usb_clear_port_feature(hdev, port1,
 974					USB_PORT_FEAT_ENABLE);
 975	}
 976	if (ret && ret != -ENODEV)
 977		dev_err(&port_dev->dev, "cannot disable (err = %d)\n", ret);
 978	return ret;
 979}
 980
 981/*
 982 * Disable a port and mark a logical connect-change event, so that some
 983 * time later hub_wq will disconnect() any existing usb_device on the port
 984 * and will re-enumerate if there actually is a device attached.
 985 */
 986static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
 987{
 988	dev_dbg(&hub->ports[port1 - 1]->dev, "logical disconnect\n");
 989	hub_port_disable(hub, port1, 1);
 990
 991	/* FIXME let caller ask to power down the port:
 992	 *  - some devices won't enumerate without a VBUS power cycle
 993	 *  - SRP saves power that way
 994	 *  - ... new call, TBD ...
 995	 * That's easy if this hub can switch power per-port, and
 996	 * hub_wq reactivates the port later (timer, SRP, etc).
 997	 * Powerdown must be optional, because of reset/DFU.
 998	 */
 999
1000	set_bit(port1, hub->change_bits);
1001	kick_hub_wq(hub);
1002}
1003
1004/**
1005 * usb_remove_device - disable a device's port on its parent hub
1006 * @udev: device to be disabled and removed
1007 * Context: @udev locked, must be able to sleep.
1008 *
1009 * After @udev's port has been disabled, hub_wq is notified and it will
1010 * see that the device has been disconnected.  When the device is
1011 * physically unplugged and something is plugged in, the events will
1012 * be received and processed normally.
1013 *
1014 * Return: 0 if successful. A negative error code otherwise.
1015 */
1016int usb_remove_device(struct usb_device *udev)
1017{
1018	struct usb_hub *hub;
1019	struct usb_interface *intf;
1020
1021	if (!udev->parent)	/* Can't remove a root hub */
1022		return -EINVAL;
1023	hub = usb_hub_to_struct_hub(udev->parent);
1024	intf = to_usb_interface(hub->intfdev);
1025
1026	usb_autopm_get_interface(intf);
1027	set_bit(udev->portnum, hub->removed_bits);
1028	hub_port_logical_disconnect(hub, udev->portnum);
1029	usb_autopm_put_interface(intf);
1030	return 0;
1031}
1032
1033enum hub_activation_type {
1034	HUB_INIT, HUB_INIT2, HUB_INIT3,		/* INITs must come first */
1035	HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
1036};
1037
1038static void hub_init_func2(struct work_struct *ws);
1039static void hub_init_func3(struct work_struct *ws);
1040
1041static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
1042{
1043	struct usb_device *hdev = hub->hdev;
1044	struct usb_hcd *hcd;
1045	int ret;
1046	int port1;
1047	int status;
1048	bool need_debounce_delay = false;
1049	unsigned delay;
1050
1051	/* Continue a partial initialization */
1052	if (type == HUB_INIT2 || type == HUB_INIT3) {
1053		device_lock(hub->intfdev);
1054
1055		/* Was the hub disconnected while we were waiting? */
1056		if (hub->disconnected) {
1057			device_unlock(hub->intfdev);
1058			kref_put(&hub->kref, hub_release);
1059			return;
1060		}
1061		if (type == HUB_INIT2)
1062			goto init2;
1063		goto init3;
1064	}
1065	kref_get(&hub->kref);
1066
1067	/* The superspeed hub except for root hub has to use Hub Depth
1068	 * value as an offset into the route string to locate the bits
1069	 * it uses to determine the downstream port number. So hub driver
1070	 * should send a set hub depth request to superspeed hub after
1071	 * the superspeed hub is set configuration in initialization or
1072	 * reset procedure.
1073	 *
1074	 * After a resume, port power should still be on.
1075	 * For any other type of activation, turn it on.
1076	 */
1077	if (type != HUB_RESUME) {
1078		if (hdev->parent && hub_is_superspeed(hdev)) {
1079			ret = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
1080					HUB_SET_DEPTH, USB_RT_HUB,
1081					hdev->level - 1, 0, NULL, 0,
1082					USB_CTRL_SET_TIMEOUT);
1083			if (ret < 0)
1084				dev_err(hub->intfdev,
1085						"set hub depth failed\n");
1086		}
1087
1088		/* Speed up system boot by using a delayed_work for the
1089		 * hub's initial power-up delays.  This is pretty awkward
1090		 * and the implementation looks like a home-brewed sort of
1091		 * setjmp/longjmp, but it saves at least 100 ms for each
1092		 * root hub (assuming usbcore is compiled into the kernel
1093		 * rather than as a module).  It adds up.
1094		 *
1095		 * This can't be done for HUB_RESUME or HUB_RESET_RESUME
1096		 * because for those activation types the ports have to be
1097		 * operational when we return.  In theory this could be done
1098		 * for HUB_POST_RESET, but it's easier not to.
1099		 */
1100		if (type == HUB_INIT) {
1101			delay = hub_power_on_good_delay(hub);
1102
1103			hub_power_on(hub, false);
1104			INIT_DELAYED_WORK(&hub->init_work, hub_init_func2);
1105			queue_delayed_work(system_power_efficient_wq,
1106					&hub->init_work,
1107					msecs_to_jiffies(delay));
1108
1109			/* Suppress autosuspend until init is done */
1110			usb_autopm_get_interface_no_resume(
1111					to_usb_interface(hub->intfdev));
1112			return;		/* Continues at init2: below */
1113		} else if (type == HUB_RESET_RESUME) {
1114			/* The internal host controller state for the hub device
1115			 * may be gone after a host power loss on system resume.
1116			 * Update the device's info so the HW knows it's a hub.
1117			 */
1118			hcd = bus_to_hcd(hdev->bus);
1119			if (hcd->driver->update_hub_device) {
1120				ret = hcd->driver->update_hub_device(hcd, hdev,
1121						&hub->tt, GFP_NOIO);
1122				if (ret < 0) {
1123					dev_err(hub->intfdev, "Host not "
1124							"accepting hub info "
1125							"update.\n");
1126					dev_err(hub->intfdev, "LS/FS devices "
1127							"and hubs may not work "
1128							"under this hub\n.");
1129				}
1130			}
1131			hub_power_on(hub, true);
1132		} else {
1133			hub_power_on(hub, true);
1134		}
1135	}
1136 init2:
1137
1138	/*
1139	 * Check each port and set hub->change_bits to let hub_wq know
1140	 * which ports need attention.
1141	 */
1142	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
1143		struct usb_port *port_dev = hub->ports[port1 - 1];
1144		struct usb_device *udev = port_dev->child;
1145		u16 portstatus, portchange;
1146
1147		portstatus = portchange = 0;
1148		status = hub_port_status(hub, port1, &portstatus, &portchange);
1149		if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
1150			dev_dbg(&port_dev->dev, "status %04x change %04x\n",
1151					portstatus, portchange);
1152
1153		/*
1154		 * After anything other than HUB_RESUME (i.e., initialization
1155		 * or any sort of reset), every port should be disabled.
1156		 * Unconnected ports should likewise be disabled (paranoia),
1157		 * and so should ports for which we have no usb_device.
1158		 */
1159		if ((portstatus & USB_PORT_STAT_ENABLE) && (
1160				type != HUB_RESUME ||
1161				!(portstatus & USB_PORT_STAT_CONNECTION) ||
1162				!udev ||
1163				udev->state == USB_STATE_NOTATTACHED)) {
1164			/*
1165			 * USB3 protocol ports will automatically transition
1166			 * to Enabled state when detect an USB3.0 device attach.
1167			 * Do not disable USB3 protocol ports, just pretend
1168			 * power was lost
1169			 */
1170			portstatus &= ~USB_PORT_STAT_ENABLE;
1171			if (!hub_is_superspeed(hdev))
1172				usb_clear_port_feature(hdev, port1,
1173						   USB_PORT_FEAT_ENABLE);
1174		}
1175
1176		/* Clear status-change flags; we'll debounce later */
1177		if (portchange & USB_PORT_STAT_C_CONNECTION) {
1178			need_debounce_delay = true;
1179			usb_clear_port_feature(hub->hdev, port1,
1180					USB_PORT_FEAT_C_CONNECTION);
1181		}
1182		if (portchange & USB_PORT_STAT_C_ENABLE) {
1183			need_debounce_delay = true;
1184			usb_clear_port_feature(hub->hdev, port1,
1185					USB_PORT_FEAT_C_ENABLE);
1186		}
1187		if (portchange & USB_PORT_STAT_C_RESET) {
1188			need_debounce_delay = true;
1189			usb_clear_port_feature(hub->hdev, port1,
1190					USB_PORT_FEAT_C_RESET);
1191		}
1192		if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
1193				hub_is_superspeed(hub->hdev)) {
1194			need_debounce_delay = true;
1195			usb_clear_port_feature(hub->hdev, port1,
1196					USB_PORT_FEAT_C_BH_PORT_RESET);
1197		}
1198		/* We can forget about a "removed" device when there's a
1199		 * physical disconnect or the connect status changes.
1200		 */
1201		if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
1202				(portchange & USB_PORT_STAT_C_CONNECTION))
1203			clear_bit(port1, hub->removed_bits);
1204
1205		if (!udev || udev->state == USB_STATE_NOTATTACHED) {
1206			/* Tell hub_wq to disconnect the device or
1207			 * check for a new connection
1208			 */
1209			if (udev || (portstatus & USB_PORT_STAT_CONNECTION) ||
1210			    (portstatus & USB_PORT_STAT_OVERCURRENT))
1211				set_bit(port1, hub->change_bits);
1212
1213		} else if (portstatus & USB_PORT_STAT_ENABLE) {
1214			bool port_resumed = (portstatus &
1215					USB_PORT_STAT_LINK_STATE) ==
1216				USB_SS_PORT_LS_U0;
1217			/* The power session apparently survived the resume.
1218			 * If there was an overcurrent or suspend change
1219			 * (i.e., remote wakeup request), have hub_wq
1220			 * take care of it.  Look at the port link state
1221			 * for USB 3.0 hubs, since they don't have a suspend
1222			 * change bit, and they don't set the port link change
1223			 * bit on device-initiated resume.
1224			 */
1225			if (portchange || (hub_is_superspeed(hub->hdev) &&
1226						port_resumed))
1227				set_bit(port1, hub->change_bits);
1228
1229		} else if (udev->persist_enabled) {
1230#ifdef CONFIG_PM
1231			udev->reset_resume = 1;
1232#endif
1233			/* Don't set the change_bits when the device
1234			 * was powered off.
1235			 */
1236			if (test_bit(port1, hub->power_bits))
1237				set_bit(port1, hub->change_bits);
1238
1239		} else {
1240			/* The power session is gone; tell hub_wq */
1241			usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1242			set_bit(port1, hub->change_bits);
1243		}
1244	}
1245
1246	/* If no port-status-change flags were set, we don't need any
1247	 * debouncing.  If flags were set we can try to debounce the
1248	 * ports all at once right now, instead of letting hub_wq do them
1249	 * one at a time later on.
1250	 *
1251	 * If any port-status changes do occur during this delay, hub_wq
1252	 * will see them later and handle them normally.
1253	 */
1254	if (need_debounce_delay) {
1255		delay = HUB_DEBOUNCE_STABLE;
1256
1257		/* Don't do a long sleep inside a workqueue routine */
1258		if (type == HUB_INIT2) {
1259			INIT_DELAYED_WORK(&hub->init_work, hub_init_func3);
1260			queue_delayed_work(system_power_efficient_wq,
1261					&hub->init_work,
1262					msecs_to_jiffies(delay));
1263			device_unlock(hub->intfdev);
1264			return;		/* Continues at init3: below */
1265		} else {
1266			msleep(delay);
1267		}
1268	}
1269 init3:
1270	hub->quiescing = 0;
1271
1272	status = usb_submit_urb(hub->urb, GFP_NOIO);
1273	if (status < 0)
1274		dev_err(hub->intfdev, "activate --> %d\n", status);
1275	if (hub->has_indicators && blinkenlights)
1276		queue_delayed_work(system_power_efficient_wq,
1277				&hub->leds, LED_CYCLE_PERIOD);
1278
1279	/* Scan all ports that need attention */
1280	kick_hub_wq(hub);
1281
1282	/* Allow autosuspend if it was suppressed */
1283	if (type <= HUB_INIT3)
 
1284		usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
1285
1286	if (type == HUB_INIT2 || type == HUB_INIT3)
1287		device_unlock(hub->intfdev);
1288
1289	kref_put(&hub->kref, hub_release);
1290}
1291
1292/* Implement the continuations for the delays above */
1293static void hub_init_func2(struct work_struct *ws)
1294{
1295	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1296
1297	hub_activate(hub, HUB_INIT2);
1298}
1299
1300static void hub_init_func3(struct work_struct *ws)
1301{
1302	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1303
1304	hub_activate(hub, HUB_INIT3);
1305}
1306
1307enum hub_quiescing_type {
1308	HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
1309};
1310
1311static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
1312{
1313	struct usb_device *hdev = hub->hdev;
1314	int i;
1315
1316	cancel_delayed_work_sync(&hub->init_work);
1317
1318	/* hub_wq and related activity won't re-trigger */
1319	hub->quiescing = 1;
1320
1321	if (type != HUB_SUSPEND) {
1322		/* Disconnect all the children */
1323		for (i = 0; i < hdev->maxchild; ++i) {
1324			if (hub->ports[i]->child)
1325				usb_disconnect(&hub->ports[i]->child);
1326		}
1327	}
1328
1329	/* Stop hub_wq and related activity */
1330	usb_kill_urb(hub->urb);
1331	if (hub->has_indicators)
1332		cancel_delayed_work_sync(&hub->leds);
1333	if (hub->tt.hub)
1334		flush_work(&hub->tt.clear_work);
1335}
1336
1337static void hub_pm_barrier_for_all_ports(struct usb_hub *hub)
1338{
1339	int i;
1340
1341	for (i = 0; i < hub->hdev->maxchild; ++i)
1342		pm_runtime_barrier(&hub->ports[i]->dev);
1343}
1344
1345/* caller has locked the hub device */
1346static int hub_pre_reset(struct usb_interface *intf)
1347{
1348	struct usb_hub *hub = usb_get_intfdata(intf);
1349
1350	hub_quiesce(hub, HUB_PRE_RESET);
1351	hub->in_reset = 1;
1352	hub_pm_barrier_for_all_ports(hub);
1353	return 0;
1354}
1355
1356/* caller has locked the hub device */
1357static int hub_post_reset(struct usb_interface *intf)
1358{
1359	struct usb_hub *hub = usb_get_intfdata(intf);
1360
1361	hub->in_reset = 0;
1362	hub_pm_barrier_for_all_ports(hub);
1363	hub_activate(hub, HUB_POST_RESET);
1364	return 0;
1365}
1366
1367static int hub_configure(struct usb_hub *hub,
1368	struct usb_endpoint_descriptor *endpoint)
1369{
1370	struct usb_hcd *hcd;
1371	struct usb_device *hdev = hub->hdev;
1372	struct device *hub_dev = hub->intfdev;
1373	u16 hubstatus, hubchange;
1374	u16 wHubCharacteristics;
1375	unsigned int pipe;
1376	int maxp, ret, i;
1377	char *message = "out of memory";
1378	unsigned unit_load;
1379	unsigned full_load;
1380	unsigned maxchild;
1381
1382	hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
1383	if (!hub->buffer) {
1384		ret = -ENOMEM;
1385		goto fail;
1386	}
1387
1388	hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
1389	if (!hub->status) {
1390		ret = -ENOMEM;
1391		goto fail;
1392	}
1393	mutex_init(&hub->status_mutex);
1394
1395	hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
1396	if (!hub->descriptor) {
1397		ret = -ENOMEM;
1398		goto fail;
1399	}
1400
1401	/* Request the entire hub descriptor.
1402	 * hub->descriptor can handle USB_MAXCHILDREN ports,
1403	 * but the hub can/will return fewer bytes here.
1404	 */
1405	ret = get_hub_descriptor(hdev, hub->descriptor);
1406	if (ret < 0) {
1407		message = "can't read hub descriptor";
1408		goto fail;
1409	} else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
1410		message = "hub has too many ports!";
1411		ret = -ENODEV;
1412		goto fail;
1413	} else if (hub->descriptor->bNbrPorts == 0) {
1414		message = "hub doesn't have any ports!";
1415		ret = -ENODEV;
1416		goto fail;
1417	}
1418
1419	maxchild = hub->descriptor->bNbrPorts;
1420	dev_info(hub_dev, "%d port%s detected\n", maxchild,
1421			(maxchild == 1) ? "" : "s");
1422
1423	hub->ports = kzalloc(maxchild * sizeof(struct usb_port *), GFP_KERNEL);
1424	if (!hub->ports) {
1425		ret = -ENOMEM;
1426		goto fail;
1427	}
1428
1429	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
1430	if (hub_is_superspeed(hdev)) {
1431		unit_load = 150;
1432		full_load = 900;
1433	} else {
1434		unit_load = 100;
1435		full_load = 500;
1436	}
1437
1438	/* FIXME for USB 3.0, skip for now */
1439	if ((wHubCharacteristics & HUB_CHAR_COMPOUND) &&
1440			!(hub_is_superspeed(hdev))) {
1441		char	portstr[USB_MAXCHILDREN + 1];
1442
1443		for (i = 0; i < maxchild; i++)
1444			portstr[i] = hub->descriptor->u.hs.DeviceRemovable
1445				    [((i + 1) / 8)] & (1 << ((i + 1) % 8))
1446				? 'F' : 'R';
1447		portstr[maxchild] = 0;
1448		dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
1449	} else
1450		dev_dbg(hub_dev, "standalone hub\n");
1451
1452	switch (wHubCharacteristics & HUB_CHAR_LPSM) {
1453	case HUB_CHAR_COMMON_LPSM:
1454		dev_dbg(hub_dev, "ganged power switching\n");
1455		break;
1456	case HUB_CHAR_INDV_PORT_LPSM:
1457		dev_dbg(hub_dev, "individual port power switching\n");
1458		break;
1459	case HUB_CHAR_NO_LPSM:
1460	case HUB_CHAR_LPSM:
1461		dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
1462		break;
1463	}
1464
1465	switch (wHubCharacteristics & HUB_CHAR_OCPM) {
1466	case HUB_CHAR_COMMON_OCPM:
1467		dev_dbg(hub_dev, "global over-current protection\n");
1468		break;
1469	case HUB_CHAR_INDV_PORT_OCPM:
1470		dev_dbg(hub_dev, "individual port over-current protection\n");
1471		break;
1472	case HUB_CHAR_NO_OCPM:
1473	case HUB_CHAR_OCPM:
1474		dev_dbg(hub_dev, "no over-current protection\n");
1475		break;
1476	}
1477
1478	spin_lock_init(&hub->tt.lock);
1479	INIT_LIST_HEAD(&hub->tt.clear_list);
1480	INIT_WORK(&hub->tt.clear_work, hub_tt_work);
1481	switch (hdev->descriptor.bDeviceProtocol) {
1482	case USB_HUB_PR_FS:
1483		break;
1484	case USB_HUB_PR_HS_SINGLE_TT:
1485		dev_dbg(hub_dev, "Single TT\n");
1486		hub->tt.hub = hdev;
1487		break;
1488	case USB_HUB_PR_HS_MULTI_TT:
1489		ret = usb_set_interface(hdev, 0, 1);
1490		if (ret == 0) {
1491			dev_dbg(hub_dev, "TT per port\n");
1492			hub->tt.multi = 1;
1493		} else
1494			dev_err(hub_dev, "Using single TT (err %d)\n",
1495				ret);
1496		hub->tt.hub = hdev;
1497		break;
1498	case USB_HUB_PR_SS:
1499		/* USB 3.0 hubs don't have a TT */
1500		break;
1501	default:
1502		dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
1503			hdev->descriptor.bDeviceProtocol);
1504		break;
1505	}
1506
1507	/* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
1508	switch (wHubCharacteristics & HUB_CHAR_TTTT) {
1509	case HUB_TTTT_8_BITS:
1510		if (hdev->descriptor.bDeviceProtocol != 0) {
1511			hub->tt.think_time = 666;
1512			dev_dbg(hub_dev, "TT requires at most %d "
1513					"FS bit times (%d ns)\n",
1514				8, hub->tt.think_time);
1515		}
1516		break;
1517	case HUB_TTTT_16_BITS:
1518		hub->tt.think_time = 666 * 2;
1519		dev_dbg(hub_dev, "TT requires at most %d "
1520				"FS bit times (%d ns)\n",
1521			16, hub->tt.think_time);
1522		break;
1523	case HUB_TTTT_24_BITS:
1524		hub->tt.think_time = 666 * 3;
1525		dev_dbg(hub_dev, "TT requires at most %d "
1526				"FS bit times (%d ns)\n",
1527			24, hub->tt.think_time);
1528		break;
1529	case HUB_TTTT_32_BITS:
1530		hub->tt.think_time = 666 * 4;
1531		dev_dbg(hub_dev, "TT requires at most %d "
1532				"FS bit times (%d ns)\n",
1533			32, hub->tt.think_time);
1534		break;
1535	}
1536
1537	/* probe() zeroes hub->indicator[] */
1538	if (wHubCharacteristics & HUB_CHAR_PORTIND) {
1539		hub->has_indicators = 1;
1540		dev_dbg(hub_dev, "Port indicators are supported\n");
1541	}
1542
1543	dev_dbg(hub_dev, "power on to power good time: %dms\n",
1544		hub->descriptor->bPwrOn2PwrGood * 2);
1545
1546	/* power budgeting mostly matters with bus-powered hubs,
1547	 * and battery-powered root hubs (may provide just 8 mA).
1548	 */
1549	ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
1550	if (ret) {
1551		message = "can't get hub status";
1552		goto fail;
1553	}
1554	hcd = bus_to_hcd(hdev->bus);
1555	if (hdev == hdev->bus->root_hub) {
1556		if (hcd->power_budget > 0)
1557			hdev->bus_mA = hcd->power_budget;
1558		else
1559			hdev->bus_mA = full_load * maxchild;
1560		if (hdev->bus_mA >= full_load)
1561			hub->mA_per_port = full_load;
1562		else {
1563			hub->mA_per_port = hdev->bus_mA;
1564			hub->limited_power = 1;
1565		}
1566	} else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1567		int remaining = hdev->bus_mA -
1568			hub->descriptor->bHubContrCurrent;
1569
1570		dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
1571			hub->descriptor->bHubContrCurrent);
1572		hub->limited_power = 1;
1573
1574		if (remaining < maxchild * unit_load)
1575			dev_warn(hub_dev,
1576					"insufficient power available "
1577					"to use all downstream ports\n");
1578		hub->mA_per_port = unit_load;	/* 7.2.1 */
1579
1580	} else {	/* Self-powered external hub */
1581		/* FIXME: What about battery-powered external hubs that
1582		 * provide less current per port? */
1583		hub->mA_per_port = full_load;
1584	}
1585	if (hub->mA_per_port < full_load)
1586		dev_dbg(hub_dev, "%umA bus power budget for each child\n",
1587				hub->mA_per_port);
1588
1589	ret = hub_hub_status(hub, &hubstatus, &hubchange);
1590	if (ret < 0) {
1591		message = "can't get hub status";
1592		goto fail;
1593	}
1594
1595	/* local power status reports aren't always correct */
1596	if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
1597		dev_dbg(hub_dev, "local power source is %s\n",
1598			(hubstatus & HUB_STATUS_LOCAL_POWER)
1599			? "lost (inactive)" : "good");
1600
1601	if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
1602		dev_dbg(hub_dev, "%sover-current condition exists\n",
1603			(hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
1604
1605	/* set up the interrupt endpoint
1606	 * We use the EP's maxpacket size instead of (PORTS+1+7)/8
1607	 * bytes as USB2.0[11.12.3] says because some hubs are known
1608	 * to send more data (and thus cause overflow). For root hubs,
1609	 * maxpktsize is defined in hcd.c's fake endpoint descriptors
1610	 * to be big enough for at least USB_MAXCHILDREN ports. */
1611	pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
1612	maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
1613
1614	if (maxp > sizeof(*hub->buffer))
1615		maxp = sizeof(*hub->buffer);
1616
1617	hub->urb = usb_alloc_urb(0, GFP_KERNEL);
1618	if (!hub->urb) {
1619		ret = -ENOMEM;
1620		goto fail;
1621	}
1622
1623	usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1624		hub, endpoint->bInterval);
1625
1626	/* maybe cycle the hub leds */
1627	if (hub->has_indicators && blinkenlights)
1628		hub->indicator[0] = INDICATOR_CYCLE;
1629
1630	mutex_lock(&usb_port_peer_mutex);
1631	for (i = 0; i < maxchild; i++) {
1632		ret = usb_hub_create_port_device(hub, i + 1);
1633		if (ret < 0) {
1634			dev_err(hub->intfdev,
1635				"couldn't create port%d device.\n", i + 1);
1636			break;
1637		}
1638	}
1639	hdev->maxchild = i;
1640	for (i = 0; i < hdev->maxchild; i++) {
1641		struct usb_port *port_dev = hub->ports[i];
1642
1643		pm_runtime_put(&port_dev->dev);
1644	}
1645
1646	mutex_unlock(&usb_port_peer_mutex);
1647	if (ret < 0)
1648		goto fail;
1649
1650	/* Update the HCD's internal representation of this hub before hub_wq
1651	 * starts getting port status changes for devices under the hub.
1652	 */
1653	if (hcd->driver->update_hub_device) {
1654		ret = hcd->driver->update_hub_device(hcd, hdev,
1655				&hub->tt, GFP_KERNEL);
1656		if (ret < 0) {
1657			message = "can't update HCD hub info";
1658			goto fail;
1659		}
1660	}
1661
1662	usb_hub_adjust_deviceremovable(hdev, hub->descriptor);
1663
1664	hub_activate(hub, HUB_INIT);
1665	return 0;
1666
1667fail:
1668	dev_err(hub_dev, "config failed, %s (err %d)\n",
1669			message, ret);
1670	/* hub_disconnect() frees urb and descriptor */
1671	return ret;
1672}
1673
1674static void hub_release(struct kref *kref)
1675{
1676	struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1677
1678	usb_put_dev(hub->hdev);
1679	usb_put_intf(to_usb_interface(hub->intfdev));
1680	kfree(hub);
1681}
1682
1683static unsigned highspeed_hubs;
1684
1685static void hub_disconnect(struct usb_interface *intf)
1686{
1687	struct usb_hub *hub = usb_get_intfdata(intf);
1688	struct usb_device *hdev = interface_to_usbdev(intf);
1689	int port1;
1690
1691	/*
1692	 * Stop adding new hub events. We do not want to block here and thus
1693	 * will not try to remove any pending work item.
1694	 */
1695	hub->disconnected = 1;
1696
1697	/* Disconnect all children and quiesce the hub */
1698	hub->error = 0;
1699	hub_quiesce(hub, HUB_DISCONNECT);
1700
1701	mutex_lock(&usb_port_peer_mutex);
1702
1703	/* Avoid races with recursively_mark_NOTATTACHED() */
1704	spin_lock_irq(&device_state_lock);
1705	port1 = hdev->maxchild;
1706	hdev->maxchild = 0;
1707	usb_set_intfdata(intf, NULL);
1708	spin_unlock_irq(&device_state_lock);
1709
1710	for (; port1 > 0; --port1)
1711		usb_hub_remove_port_device(hub, port1);
1712
1713	mutex_unlock(&usb_port_peer_mutex);
1714
1715	if (hub->hdev->speed == USB_SPEED_HIGH)
1716		highspeed_hubs--;
1717
1718	usb_free_urb(hub->urb);
1719	kfree(hub->ports);
1720	kfree(hub->descriptor);
1721	kfree(hub->status);
1722	kfree(hub->buffer);
1723
1724	pm_suspend_ignore_children(&intf->dev, false);
1725	kref_put(&hub->kref, hub_release);
1726}
1727
1728static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1729{
1730	struct usb_host_interface *desc;
1731	struct usb_endpoint_descriptor *endpoint;
1732	struct usb_device *hdev;
1733	struct usb_hub *hub;
1734
1735	desc = intf->cur_altsetting;
1736	hdev = interface_to_usbdev(intf);
1737
1738	/*
1739	 * Set default autosuspend delay as 0 to speedup bus suspend,
1740	 * based on the below considerations:
1741	 *
1742	 * - Unlike other drivers, the hub driver does not rely on the
1743	 *   autosuspend delay to provide enough time to handle a wakeup
1744	 *   event, and the submitted status URB is just to check future
1745	 *   change on hub downstream ports, so it is safe to do it.
1746	 *
1747	 * - The patch might cause one or more auto supend/resume for
1748	 *   below very rare devices when they are plugged into hub
1749	 *   first time:
1750	 *
1751	 *   	devices having trouble initializing, and disconnect
1752	 *   	themselves from the bus and then reconnect a second
1753	 *   	or so later
1754	 *
1755	 *   	devices just for downloading firmware, and disconnects
1756	 *   	themselves after completing it
1757	 *
1758	 *   For these quite rare devices, their drivers may change the
1759	 *   autosuspend delay of their parent hub in the probe() to one
1760	 *   appropriate value to avoid the subtle problem if someone
1761	 *   does care it.
1762	 *
1763	 * - The patch may cause one or more auto suspend/resume on
1764	 *   hub during running 'lsusb', but it is probably too
1765	 *   infrequent to worry about.
1766	 *
1767	 * - Change autosuspend delay of hub can avoid unnecessary auto
1768	 *   suspend timer for hub, also may decrease power consumption
1769	 *   of USB bus.
1770	 *
1771	 * - If user has indicated to prevent autosuspend by passing
1772	 *   usbcore.autosuspend = -1 then keep autosuspend disabled.
1773	 */
1774#ifdef CONFIG_PM
1775	if (hdev->dev.power.autosuspend_delay >= 0)
1776		pm_runtime_set_autosuspend_delay(&hdev->dev, 0);
1777#endif
1778
1779	/*
1780	 * Hubs have proper suspend/resume support, except for root hubs
1781	 * where the controller driver doesn't have bus_suspend and
1782	 * bus_resume methods.
1783	 */
1784	if (hdev->parent) {		/* normal device */
1785		usb_enable_autosuspend(hdev);
1786	} else {			/* root hub */
1787		const struct hc_driver *drv = bus_to_hcd(hdev->bus)->driver;
1788
1789		if (drv->bus_suspend && drv->bus_resume)
1790			usb_enable_autosuspend(hdev);
1791	}
1792
1793	if (hdev->level == MAX_TOPO_LEVEL) {
1794		dev_err(&intf->dev,
1795			"Unsupported bus topology: hub nested too deep\n");
1796		return -E2BIG;
1797	}
1798
1799#ifdef	CONFIG_USB_OTG_BLACKLIST_HUB
1800	if (hdev->parent) {
1801		dev_warn(&intf->dev, "ignoring external hub\n");
1802		return -ENODEV;
1803	}
1804#endif
1805
1806	/* Some hubs have a subclass of 1, which AFAICT according to the */
1807	/*  specs is not defined, but it works */
1808	if ((desc->desc.bInterfaceSubClass != 0) &&
1809	    (desc->desc.bInterfaceSubClass != 1)) {
1810descriptor_error:
1811		dev_err(&intf->dev, "bad descriptor, ignoring hub\n");
1812		return -EIO;
1813	}
1814
1815	/* Multiple endpoints? What kind of mutant ninja-hub is this? */
1816	if (desc->desc.bNumEndpoints != 1)
1817		goto descriptor_error;
1818
1819	endpoint = &desc->endpoint[0].desc;
1820
1821	/* If it's not an interrupt in endpoint, we'd better punt! */
1822	if (!usb_endpoint_is_int_in(endpoint))
1823		goto descriptor_error;
1824
1825	/* We found a hub */
1826	dev_info(&intf->dev, "USB hub found\n");
1827
1828	hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1829	if (!hub) {
1830		dev_dbg(&intf->dev, "couldn't kmalloc hub struct\n");
1831		return -ENOMEM;
1832	}
1833
1834	kref_init(&hub->kref);
1835	hub->intfdev = &intf->dev;
1836	hub->hdev = hdev;
1837	INIT_DELAYED_WORK(&hub->leds, led_work);
1838	INIT_DELAYED_WORK(&hub->init_work, NULL);
1839	INIT_WORK(&hub->events, hub_event);
1840	usb_get_intf(intf);
1841	usb_get_dev(hdev);
1842
1843	usb_set_intfdata(intf, hub);
1844	intf->needs_remote_wakeup = 1;
1845	pm_suspend_ignore_children(&intf->dev, true);
1846
1847	if (hdev->speed == USB_SPEED_HIGH)
1848		highspeed_hubs++;
1849
1850	if (id->driver_info & HUB_QUIRK_CHECK_PORT_AUTOSUSPEND)
1851		hub->quirk_check_port_auto_suspend = 1;
1852
1853	if (hub_configure(hub, endpoint) >= 0)
1854		return 0;
1855
1856	hub_disconnect(intf);
1857	return -ENODEV;
1858}
1859
1860static int
1861hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1862{
1863	struct usb_device *hdev = interface_to_usbdev(intf);
1864	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
1865
1866	/* assert ifno == 0 (part of hub spec) */
1867	switch (code) {
1868	case USBDEVFS_HUB_PORTINFO: {
1869		struct usbdevfs_hub_portinfo *info = user_data;
1870		int i;
1871
1872		spin_lock_irq(&device_state_lock);
1873		if (hdev->devnum <= 0)
1874			info->nports = 0;
1875		else {
1876			info->nports = hdev->maxchild;
1877			for (i = 0; i < info->nports; i++) {
1878				if (hub->ports[i]->child == NULL)
1879					info->port[i] = 0;
1880				else
1881					info->port[i] =
1882						hub->ports[i]->child->devnum;
1883			}
1884		}
1885		spin_unlock_irq(&device_state_lock);
1886
1887		return info->nports + 1;
1888		}
1889
1890	default:
1891		return -ENOSYS;
1892	}
1893}
1894
1895/*
1896 * Allow user programs to claim ports on a hub.  When a device is attached
1897 * to one of these "claimed" ports, the program will "own" the device.
1898 */
1899static int find_port_owner(struct usb_device *hdev, unsigned port1,
1900		struct usb_dev_state ***ppowner)
1901{
1902	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
1903
1904	if (hdev->state == USB_STATE_NOTATTACHED)
1905		return -ENODEV;
1906	if (port1 == 0 || port1 > hdev->maxchild)
1907		return -EINVAL;
1908
1909	/* Devices not managed by the hub driver
1910	 * will always have maxchild equal to 0.
1911	 */
1912	*ppowner = &(hub->ports[port1 - 1]->port_owner);
1913	return 0;
1914}
1915
1916/* In the following three functions, the caller must hold hdev's lock */
1917int usb_hub_claim_port(struct usb_device *hdev, unsigned port1,
1918		       struct usb_dev_state *owner)
1919{
1920	int rc;
1921	struct usb_dev_state **powner;
1922
1923	rc = find_port_owner(hdev, port1, &powner);
1924	if (rc)
1925		return rc;
1926	if (*powner)
1927		return -EBUSY;
1928	*powner = owner;
1929	return rc;
1930}
1931EXPORT_SYMBOL_GPL(usb_hub_claim_port);
1932
1933int usb_hub_release_port(struct usb_device *hdev, unsigned port1,
1934			 struct usb_dev_state *owner)
1935{
1936	int rc;
1937	struct usb_dev_state **powner;
1938
1939	rc = find_port_owner(hdev, port1, &powner);
1940	if (rc)
1941		return rc;
1942	if (*powner != owner)
1943		return -ENOENT;
1944	*powner = NULL;
1945	return rc;
1946}
1947EXPORT_SYMBOL_GPL(usb_hub_release_port);
1948
1949void usb_hub_release_all_ports(struct usb_device *hdev, struct usb_dev_state *owner)
1950{
1951	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
1952	int n;
1953
1954	for (n = 0; n < hdev->maxchild; n++) {
1955		if (hub->ports[n]->port_owner == owner)
1956			hub->ports[n]->port_owner = NULL;
1957	}
1958
1959}
1960
1961/* The caller must hold udev's lock */
1962bool usb_device_is_owned(struct usb_device *udev)
1963{
1964	struct usb_hub *hub;
1965
1966	if (udev->state == USB_STATE_NOTATTACHED || !udev->parent)
1967		return false;
1968	hub = usb_hub_to_struct_hub(udev->parent);
1969	return !!hub->ports[udev->portnum - 1]->port_owner;
1970}
1971
1972static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1973{
1974	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
1975	int i;
1976
1977	for (i = 0; i < udev->maxchild; ++i) {
1978		if (hub->ports[i]->child)
1979			recursively_mark_NOTATTACHED(hub->ports[i]->child);
1980	}
1981	if (udev->state == USB_STATE_SUSPENDED)
1982		udev->active_duration -= jiffies;
1983	udev->state = USB_STATE_NOTATTACHED;
1984}
1985
1986/**
1987 * usb_set_device_state - change a device's current state (usbcore, hcds)
1988 * @udev: pointer to device whose state should be changed
1989 * @new_state: new state value to be stored
1990 *
1991 * udev->state is _not_ fully protected by the device lock.  Although
1992 * most transitions are made only while holding the lock, the state can
1993 * can change to USB_STATE_NOTATTACHED at almost any time.  This
1994 * is so that devices can be marked as disconnected as soon as possible,
1995 * without having to wait for any semaphores to be released.  As a result,
1996 * all changes to any device's state must be protected by the
1997 * device_state_lock spinlock.
1998 *
1999 * Once a device has been added to the device tree, all changes to its state
2000 * should be made using this routine.  The state should _not_ be set directly.
2001 *
2002 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
2003 * Otherwise udev->state is set to new_state, and if new_state is
2004 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
2005 * to USB_STATE_NOTATTACHED.
2006 */
2007void usb_set_device_state(struct usb_device *udev,
2008		enum usb_device_state new_state)
2009{
2010	unsigned long flags;
2011	int wakeup = -1;
2012
2013	spin_lock_irqsave(&device_state_lock, flags);
2014	if (udev->state == USB_STATE_NOTATTACHED)
2015		;	/* do nothing */
2016	else if (new_state != USB_STATE_NOTATTACHED) {
2017
2018		/* root hub wakeup capabilities are managed out-of-band
2019		 * and may involve silicon errata ... ignore them here.
2020		 */
2021		if (udev->parent) {
2022			if (udev->state == USB_STATE_SUSPENDED
2023					|| new_state == USB_STATE_SUSPENDED)
2024				;	/* No change to wakeup settings */
2025			else if (new_state == USB_STATE_CONFIGURED)
2026				wakeup = (udev->quirks &
2027					USB_QUIRK_IGNORE_REMOTE_WAKEUP) ? 0 :
2028					udev->actconfig->desc.bmAttributes &
2029					USB_CONFIG_ATT_WAKEUP;
2030			else
2031				wakeup = 0;
2032		}
2033		if (udev->state == USB_STATE_SUSPENDED &&
2034			new_state != USB_STATE_SUSPENDED)
2035			udev->active_duration -= jiffies;
2036		else if (new_state == USB_STATE_SUSPENDED &&
2037				udev->state != USB_STATE_SUSPENDED)
2038			udev->active_duration += jiffies;
2039		udev->state = new_state;
2040	} else
2041		recursively_mark_NOTATTACHED(udev);
2042	spin_unlock_irqrestore(&device_state_lock, flags);
2043	if (wakeup >= 0)
2044		device_set_wakeup_capable(&udev->dev, wakeup);
2045}
2046EXPORT_SYMBOL_GPL(usb_set_device_state);
2047
2048/*
2049 * Choose a device number.
2050 *
2051 * Device numbers are used as filenames in usbfs.  On USB-1.1 and
2052 * USB-2.0 buses they are also used as device addresses, however on
2053 * USB-3.0 buses the address is assigned by the controller hardware
2054 * and it usually is not the same as the device number.
2055 *
2056 * WUSB devices are simple: they have no hubs behind, so the mapping
2057 * device <-> virtual port number becomes 1:1. Why? to simplify the
2058 * life of the device connection logic in
2059 * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
2060 * handshake we need to assign a temporary address in the unauthorized
2061 * space. For simplicity we use the first virtual port number found to
2062 * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
2063 * and that becomes it's address [X < 128] or its unauthorized address
2064 * [X | 0x80].
2065 *
2066 * We add 1 as an offset to the one-based USB-stack port number
2067 * (zero-based wusb virtual port index) for two reasons: (a) dev addr
2068 * 0 is reserved by USB for default address; (b) Linux's USB stack
2069 * uses always #1 for the root hub of the controller. So USB stack's
2070 * port #1, which is wusb virtual-port #0 has address #2.
2071 *
2072 * Devices connected under xHCI are not as simple.  The host controller
2073 * supports virtualization, so the hardware assigns device addresses and
2074 * the HCD must setup data structures before issuing a set address
2075 * command to the hardware.
2076 */
2077static void choose_devnum(struct usb_device *udev)
2078{
2079	int		devnum;
2080	struct usb_bus	*bus = udev->bus;
2081
2082	/* be safe when more hub events are proceed in parallel */
2083	mutex_lock(&bus->usb_address0_mutex);
2084	if (udev->wusb) {
2085		devnum = udev->portnum + 1;
2086		BUG_ON(test_bit(devnum, bus->devmap.devicemap));
2087	} else {
2088		/* Try to allocate the next devnum beginning at
2089		 * bus->devnum_next. */
2090		devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
2091					    bus->devnum_next);
2092		if (devnum >= 128)
2093			devnum = find_next_zero_bit(bus->devmap.devicemap,
2094						    128, 1);
2095		bus->devnum_next = (devnum >= 127 ? 1 : devnum + 1);
2096	}
2097	if (devnum < 128) {
2098		set_bit(devnum, bus->devmap.devicemap);
2099		udev->devnum = devnum;
2100	}
2101	mutex_unlock(&bus->usb_address0_mutex);
2102}
2103
2104static void release_devnum(struct usb_device *udev)
2105{
2106	if (udev->devnum > 0) {
2107		clear_bit(udev->devnum, udev->bus->devmap.devicemap);
2108		udev->devnum = -1;
2109	}
2110}
2111
2112static void update_devnum(struct usb_device *udev, int devnum)
2113{
2114	/* The address for a WUSB device is managed by wusbcore. */
2115	if (!udev->wusb)
2116		udev->devnum = devnum;
2117}
2118
2119static void hub_free_dev(struct usb_device *udev)
2120{
2121	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2122
2123	/* Root hubs aren't real devices, so don't free HCD resources */
2124	if (hcd->driver->free_dev && udev->parent)
2125		hcd->driver->free_dev(hcd, udev);
2126}
2127
2128static void hub_disconnect_children(struct usb_device *udev)
2129{
2130	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
2131	int i;
2132
2133	/* Free up all the children before we remove this device */
2134	for (i = 0; i < udev->maxchild; i++) {
2135		if (hub->ports[i]->child)
2136			usb_disconnect(&hub->ports[i]->child);
2137	}
2138}
2139
2140/**
2141 * usb_disconnect - disconnect a device (usbcore-internal)
2142 * @pdev: pointer to device being disconnected
2143 * Context: !in_interrupt ()
2144 *
2145 * Something got disconnected. Get rid of it and all of its children.
2146 *
2147 * If *pdev is a normal device then the parent hub must already be locked.
2148 * If *pdev is a root hub then the caller must hold the usb_bus_idr_lock,
2149 * which protects the set of root hubs as well as the list of buses.
2150 *
2151 * Only hub drivers (including virtual root hub drivers for host
2152 * controllers) should ever call this.
2153 *
2154 * This call is synchronous, and may not be used in an interrupt context.
2155 */
2156void usb_disconnect(struct usb_device **pdev)
2157{
2158	struct usb_port *port_dev = NULL;
2159	struct usb_device *udev = *pdev;
2160	struct usb_hub *hub = NULL;
2161	int port1 = 1;
2162
2163	/* mark the device as inactive, so any further urb submissions for
2164	 * this device (and any of its children) will fail immediately.
2165	 * this quiesces everything except pending urbs.
2166	 */
2167	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2168	dev_info(&udev->dev, "USB disconnect, device number %d\n",
2169			udev->devnum);
2170
2171	usb_lock_device(udev);
2172
2173	hub_disconnect_children(udev);
2174
2175	/* deallocate hcd/hardware state ... nuking all pending urbs and
2176	 * cleaning up all state associated with the current configuration
2177	 * so that the hardware is now fully quiesced.
2178	 */
2179	dev_dbg(&udev->dev, "unregistering device\n");
2180	usb_disable_device(udev, 0);
2181	usb_hcd_synchronize_unlinks(udev);
2182
2183	if (udev->parent) {
2184		port1 = udev->portnum;
2185		hub = usb_hub_to_struct_hub(udev->parent);
2186		port_dev = hub->ports[port1 - 1];
2187
2188		sysfs_remove_link(&udev->dev.kobj, "port");
2189		sysfs_remove_link(&port_dev->dev.kobj, "device");
2190
2191		/*
2192		 * As usb_port_runtime_resume() de-references udev, make
2193		 * sure no resumes occur during removal
2194		 */
2195		if (!test_and_set_bit(port1, hub->child_usage_bits))
2196			pm_runtime_get_sync(&port_dev->dev);
2197	}
2198
2199	usb_remove_ep_devs(&udev->ep0);
2200	usb_unlock_device(udev);
2201
2202	/* Unregister the device.  The device driver is responsible
2203	 * for de-configuring the device and invoking the remove-device
2204	 * notifier chain (used by usbfs and possibly others).
2205	 */
2206	device_del(&udev->dev);
2207
2208	/* Free the device number and delete the parent's children[]
2209	 * (or root_hub) pointer.
2210	 */
2211	release_devnum(udev);
2212
2213	/* Avoid races with recursively_mark_NOTATTACHED() */
2214	spin_lock_irq(&device_state_lock);
2215	*pdev = NULL;
2216	spin_unlock_irq(&device_state_lock);
2217
2218	if (port_dev && test_and_clear_bit(port1, hub->child_usage_bits))
2219		pm_runtime_put(&port_dev->dev);
2220
2221	hub_free_dev(udev);
2222
2223	put_device(&udev->dev);
2224}
2225
2226#ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
2227static void show_string(struct usb_device *udev, char *id, char *string)
2228{
2229	if (!string)
2230		return;
2231	dev_info(&udev->dev, "%s: %s\n", id, string);
2232}
2233
2234static void announce_device(struct usb_device *udev)
2235{
2236	dev_info(&udev->dev, "New USB device found, idVendor=%04x, idProduct=%04x\n",
2237		le16_to_cpu(udev->descriptor.idVendor),
2238		le16_to_cpu(udev->descriptor.idProduct));
2239	dev_info(&udev->dev,
2240		"New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
2241		udev->descriptor.iManufacturer,
2242		udev->descriptor.iProduct,
2243		udev->descriptor.iSerialNumber);
2244	show_string(udev, "Product", udev->product);
2245	show_string(udev, "Manufacturer", udev->manufacturer);
2246	show_string(udev, "SerialNumber", udev->serial);
2247}
2248#else
2249static inline void announce_device(struct usb_device *udev) { }
2250#endif
2251
2252
2253/**
2254 * usb_enumerate_device_otg - FIXME (usbcore-internal)
2255 * @udev: newly addressed device (in ADDRESS state)
2256 *
2257 * Finish enumeration for On-The-Go devices
2258 *
2259 * Return: 0 if successful. A negative error code otherwise.
2260 */
2261static int usb_enumerate_device_otg(struct usb_device *udev)
2262{
2263	int err = 0;
2264
2265#ifdef	CONFIG_USB_OTG
2266	/*
2267	 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
2268	 * to wake us after we've powered off VBUS; and HNP, switching roles
2269	 * "host" to "peripheral".  The OTG descriptor helps figure this out.
2270	 */
2271	if (!udev->bus->is_b_host
2272			&& udev->config
2273			&& udev->parent == udev->bus->root_hub) {
2274		struct usb_otg_descriptor	*desc = NULL;
2275		struct usb_bus			*bus = udev->bus;
2276		unsigned			port1 = udev->portnum;
2277
2278		/* descriptor may appear anywhere in config */
2279		err = __usb_get_extra_descriptor(udev->rawdescriptors[0],
2280				le16_to_cpu(udev->config[0].desc.wTotalLength),
2281				USB_DT_OTG, (void **) &desc);
2282		if (err || !(desc->bmAttributes & USB_OTG_HNP))
2283			return 0;
2284
2285		dev_info(&udev->dev, "Dual-Role OTG device on %sHNP port\n",
2286					(port1 == bus->otg_port) ? "" : "non-");
2287
2288		/* enable HNP before suspend, it's simpler */
2289		if (port1 == bus->otg_port) {
2290			bus->b_hnp_enable = 1;
2291			err = usb_control_msg(udev,
2292				usb_sndctrlpipe(udev, 0),
2293				USB_REQ_SET_FEATURE, 0,
2294				USB_DEVICE_B_HNP_ENABLE,
2295				0, NULL, 0,
2296				USB_CTRL_SET_TIMEOUT);
2297			if (err < 0) {
2298				/*
2299				 * OTG MESSAGE: report errors here,
2300				 * customize to match your product.
2301				 */
2302				dev_err(&udev->dev, "can't set HNP mode: %d\n",
2303									err);
2304				bus->b_hnp_enable = 0;
2305			}
2306		} else if (desc->bLength == sizeof
2307				(struct usb_otg_descriptor)) {
2308			/* Set a_alt_hnp_support for legacy otg device */
2309			err = usb_control_msg(udev,
2310				usb_sndctrlpipe(udev, 0),
2311				USB_REQ_SET_FEATURE, 0,
2312				USB_DEVICE_A_ALT_HNP_SUPPORT,
2313				0, NULL, 0,
2314				USB_CTRL_SET_TIMEOUT);
2315			if (err < 0)
2316				dev_err(&udev->dev,
2317					"set a_alt_hnp_support failed: %d\n",
2318					err);
2319		}
2320	}
2321#endif
2322	return err;
2323}
2324
2325
2326/**
2327 * usb_enumerate_device - Read device configs/intfs/otg (usbcore-internal)
2328 * @udev: newly addressed device (in ADDRESS state)
2329 *
2330 * This is only called by usb_new_device() and usb_authorize_device()
2331 * and FIXME -- all comments that apply to them apply here wrt to
2332 * environment.
2333 *
2334 * If the device is WUSB and not authorized, we don't attempt to read
2335 * the string descriptors, as they will be errored out by the device
2336 * until it has been authorized.
2337 *
2338 * Return: 0 if successful. A negative error code otherwise.
2339 */
2340static int usb_enumerate_device(struct usb_device *udev)
2341{
2342	int err;
2343	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2344
2345	if (udev->config == NULL) {
2346		err = usb_get_configuration(udev);
2347		if (err < 0) {
2348			if (err != -ENODEV)
2349				dev_err(&udev->dev, "can't read configurations, error %d\n",
2350						err);
2351			return err;
2352		}
2353	}
2354
2355	/* read the standard strings and cache them if present */
2356	udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
2357	udev->manufacturer = usb_cache_string(udev,
2358					      udev->descriptor.iManufacturer);
2359	udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
2360
2361	err = usb_enumerate_device_otg(udev);
2362	if (err < 0)
2363		return err;
2364
2365	if (IS_ENABLED(CONFIG_USB_OTG_WHITELIST) && hcd->tpl_support &&
2366		!is_targeted(udev)) {
2367		/* Maybe it can talk to us, though we can't talk to it.
2368		 * (Includes HNP test device.)
2369		 */
2370		if (IS_ENABLED(CONFIG_USB_OTG) && (udev->bus->b_hnp_enable
2371			|| udev->bus->is_b_host)) {
2372			err = usb_port_suspend(udev, PMSG_AUTO_SUSPEND);
2373			if (err < 0)
2374				dev_dbg(&udev->dev, "HNP fail, %d\n", err);
2375		}
2376		return -ENOTSUPP;
2377	}
2378
2379	usb_detect_interface_quirks(udev);
2380
2381	return 0;
2382}
2383
2384static void set_usb_port_removable(struct usb_device *udev)
2385{
2386	struct usb_device *hdev = udev->parent;
2387	struct usb_hub *hub;
2388	u8 port = udev->portnum;
2389	u16 wHubCharacteristics;
2390	bool removable = true;
2391
2392	if (!hdev)
2393		return;
2394
2395	hub = usb_hub_to_struct_hub(udev->parent);
2396
2397	/*
2398	 * If the platform firmware has provided information about a port,
2399	 * use that to determine whether it's removable.
2400	 */
2401	switch (hub->ports[udev->portnum - 1]->connect_type) {
2402	case USB_PORT_CONNECT_TYPE_HOT_PLUG:
2403		udev->removable = USB_DEVICE_REMOVABLE;
2404		return;
2405	case USB_PORT_CONNECT_TYPE_HARD_WIRED:
2406	case USB_PORT_NOT_USED:
2407		udev->removable = USB_DEVICE_FIXED;
2408		return;
2409	default:
2410		break;
2411	}
2412
2413	/*
2414	 * Otherwise, check whether the hub knows whether a port is removable
2415	 * or not
2416	 */
2417	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2418
2419	if (!(wHubCharacteristics & HUB_CHAR_COMPOUND))
2420		return;
2421
2422	if (hub_is_superspeed(hdev)) {
2423		if (le16_to_cpu(hub->descriptor->u.ss.DeviceRemovable)
2424				& (1 << port))
2425			removable = false;
2426	} else {
2427		if (hub->descriptor->u.hs.DeviceRemovable[port / 8] & (1 << (port % 8)))
2428			removable = false;
2429	}
2430
2431	if (removable)
2432		udev->removable = USB_DEVICE_REMOVABLE;
2433	else
2434		udev->removable = USB_DEVICE_FIXED;
2435
2436}
2437
2438/**
2439 * usb_new_device - perform initial device setup (usbcore-internal)
2440 * @udev: newly addressed device (in ADDRESS state)
2441 *
2442 * This is called with devices which have been detected but not fully
2443 * enumerated.  The device descriptor is available, but not descriptors
2444 * for any device configuration.  The caller must have locked either
2445 * the parent hub (if udev is a normal device) or else the
2446 * usb_bus_idr_lock (if udev is a root hub).  The parent's pointer to
2447 * udev has already been installed, but udev is not yet visible through
2448 * sysfs or other filesystem code.
2449 *
2450 * This call is synchronous, and may not be used in an interrupt context.
2451 *
2452 * Only the hub driver or root-hub registrar should ever call this.
2453 *
2454 * Return: Whether the device is configured properly or not. Zero if the
2455 * interface was registered with the driver core; else a negative errno
2456 * value.
2457 *
2458 */
2459int usb_new_device(struct usb_device *udev)
2460{
2461	int err;
2462
2463	if (udev->parent) {
2464		/* Initialize non-root-hub device wakeup to disabled;
2465		 * device (un)configuration controls wakeup capable
2466		 * sysfs power/wakeup controls wakeup enabled/disabled
2467		 */
2468		device_init_wakeup(&udev->dev, 0);
2469	}
2470
2471	/* Tell the runtime-PM framework the device is active */
2472	pm_runtime_set_active(&udev->dev);
2473	pm_runtime_get_noresume(&udev->dev);
2474	pm_runtime_use_autosuspend(&udev->dev);
2475	pm_runtime_enable(&udev->dev);
2476
2477	/* By default, forbid autosuspend for all devices.  It will be
2478	 * allowed for hubs during binding.
2479	 */
2480	usb_disable_autosuspend(udev);
2481
2482	err = usb_enumerate_device(udev);	/* Read descriptors */
2483	if (err < 0)
2484		goto fail;
2485	dev_dbg(&udev->dev, "udev %d, busnum %d, minor = %d\n",
2486			udev->devnum, udev->bus->busnum,
2487			(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2488	/* export the usbdev device-node for libusb */
2489	udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
2490			(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2491
2492	/* Tell the world! */
2493	announce_device(udev);
2494
2495	if (udev->serial)
2496		add_device_randomness(udev->serial, strlen(udev->serial));
2497	if (udev->product)
2498		add_device_randomness(udev->product, strlen(udev->product));
2499	if (udev->manufacturer)
2500		add_device_randomness(udev->manufacturer,
2501				      strlen(udev->manufacturer));
2502
2503	device_enable_async_suspend(&udev->dev);
2504
2505	/* check whether the hub or firmware marks this port as non-removable */
2506	if (udev->parent)
2507		set_usb_port_removable(udev);
2508
2509	/* Register the device.  The device driver is responsible
2510	 * for configuring the device and invoking the add-device
2511	 * notifier chain (used by usbfs and possibly others).
2512	 */
2513	err = device_add(&udev->dev);
2514	if (err) {
2515		dev_err(&udev->dev, "can't device_add, error %d\n", err);
2516		goto fail;
2517	}
2518
2519	/* Create link files between child device and usb port device. */
2520	if (udev->parent) {
2521		struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
2522		int port1 = udev->portnum;
2523		struct usb_port	*port_dev = hub->ports[port1 - 1];
2524
2525		err = sysfs_create_link(&udev->dev.kobj,
2526				&port_dev->dev.kobj, "port");
2527		if (err)
2528			goto fail;
2529
2530		err = sysfs_create_link(&port_dev->dev.kobj,
2531				&udev->dev.kobj, "device");
2532		if (err) {
2533			sysfs_remove_link(&udev->dev.kobj, "port");
2534			goto fail;
2535		}
2536
2537		if (!test_and_set_bit(port1, hub->child_usage_bits))
2538			pm_runtime_get_sync(&port_dev->dev);
2539	}
2540
2541	(void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev);
2542	usb_mark_last_busy(udev);
2543	pm_runtime_put_sync_autosuspend(&udev->dev);
2544	return err;
2545
2546fail:
2547	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2548	pm_runtime_disable(&udev->dev);
2549	pm_runtime_set_suspended(&udev->dev);
2550	return err;
2551}
2552
2553
2554/**
2555 * usb_deauthorize_device - deauthorize a device (usbcore-internal)
2556 * @usb_dev: USB device
2557 *
2558 * Move the USB device to a very basic state where interfaces are disabled
2559 * and the device is in fact unconfigured and unusable.
2560 *
2561 * We share a lock (that we have) with device_del(), so we need to
2562 * defer its call.
2563 *
2564 * Return: 0.
2565 */
2566int usb_deauthorize_device(struct usb_device *usb_dev)
2567{
2568	usb_lock_device(usb_dev);
2569	if (usb_dev->authorized == 0)
2570		goto out_unauthorized;
2571
2572	usb_dev->authorized = 0;
2573	usb_set_configuration(usb_dev, -1);
2574
2575out_unauthorized:
2576	usb_unlock_device(usb_dev);
2577	return 0;
2578}
2579
2580
2581int usb_authorize_device(struct usb_device *usb_dev)
2582{
2583	int result = 0, c;
2584
2585	usb_lock_device(usb_dev);
2586	if (usb_dev->authorized == 1)
2587		goto out_authorized;
2588
2589	result = usb_autoresume_device(usb_dev);
2590	if (result < 0) {
2591		dev_err(&usb_dev->dev,
2592			"can't autoresume for authorization: %d\n", result);
2593		goto error_autoresume;
2594	}
2595
2596	if (usb_dev->wusb) {
2597		result = usb_get_device_descriptor(usb_dev, sizeof(usb_dev->descriptor));
2598		if (result < 0) {
2599			dev_err(&usb_dev->dev, "can't re-read device descriptor for "
2600				"authorization: %d\n", result);
2601			goto error_device_descriptor;
2602		}
2603	}
2604
2605	usb_dev->authorized = 1;
2606	/* Choose and set the configuration.  This registers the interfaces
2607	 * with the driver core and lets interface drivers bind to them.
2608	 */
2609	c = usb_choose_configuration(usb_dev);
2610	if (c >= 0) {
2611		result = usb_set_configuration(usb_dev, c);
2612		if (result) {
2613			dev_err(&usb_dev->dev,
2614				"can't set config #%d, error %d\n", c, result);
2615			/* This need not be fatal.  The user can try to
2616			 * set other configurations. */
2617		}
2618	}
2619	dev_info(&usb_dev->dev, "authorized to connect\n");
2620
2621error_device_descriptor:
2622	usb_autosuspend_device(usb_dev);
2623error_autoresume:
2624out_authorized:
2625	usb_unlock_device(usb_dev);	/* complements locktree */
2626	return result;
2627}
2628
2629/*
2630 * Return 1 if port speed is SuperSpeedPlus, 0 otherwise
2631 * check it from the link protocol field of the current speed ID attribute.
2632 * current speed ID is got from ext port status request. Sublink speed attribute
2633 * table is returned with the hub BOS SSP device capability descriptor
2634 */
2635static int port_speed_is_ssp(struct usb_device *hdev, int speed_id)
2636{
2637	int ssa_count;
2638	u32 ss_attr;
2639	int i;
2640	struct usb_ssp_cap_descriptor *ssp_cap = hdev->bos->ssp_cap;
2641
2642	if (!ssp_cap)
2643		return 0;
2644
2645	ssa_count = le32_to_cpu(ssp_cap->bmAttributes) &
2646		USB_SSP_SUBLINK_SPEED_ATTRIBS;
2647
2648	for (i = 0; i <= ssa_count; i++) {
2649		ss_attr = le32_to_cpu(ssp_cap->bmSublinkSpeedAttr[i]);
2650		if (speed_id == (ss_attr & USB_SSP_SUBLINK_SPEED_SSID))
2651			return !!(ss_attr & USB_SSP_SUBLINK_SPEED_LP);
2652	}
2653	return 0;
2654}
2655
2656/* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
2657static unsigned hub_is_wusb(struct usb_hub *hub)
2658{
2659	struct usb_hcd *hcd;
2660	if (hub->hdev->parent != NULL)  /* not a root hub? */
2661		return 0;
2662	hcd = bus_to_hcd(hub->hdev->bus);
2663	return hcd->wireless;
2664}
2665
2666
2667#define PORT_RESET_TRIES	5
2668#define SET_ADDRESS_TRIES	2
2669#define GET_DESCRIPTOR_TRIES	2
2670#define SET_CONFIG_TRIES	(2 * (use_both_schemes + 1))
2671#define USE_NEW_SCHEME(i)	((i) / 2 == (int)old_scheme_first)
2672
2673#define HUB_ROOT_RESET_TIME	50	/* times are in msec */
2674#define HUB_SHORT_RESET_TIME	10
2675#define HUB_BH_RESET_TIME	50
2676#define HUB_LONG_RESET_TIME	200
2677#define HUB_RESET_TIMEOUT	800
2678
2679/*
2680 * "New scheme" enumeration causes an extra state transition to be
2681 * exposed to an xhci host and causes USB3 devices to receive control
2682 * commands in the default state.  This has been seen to cause
2683 * enumeration failures, so disable this enumeration scheme for USB3
2684 * devices.
2685 */
2686static bool use_new_scheme(struct usb_device *udev, int retry)
2687{
2688	if (udev->speed >= USB_SPEED_SUPER)
2689		return false;
2690
2691	return USE_NEW_SCHEME(retry);
2692}
2693
2694/* Is a USB 3.0 port in the Inactive or Compliance Mode state?
2695 * Port worm reset is required to recover
2696 */
2697static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
2698		u16 portstatus)
2699{
2700	u16 link_state;
2701
2702	if (!hub_is_superspeed(hub->hdev))
2703		return false;
2704
2705	if (test_bit(port1, hub->warm_reset_bits))
2706		return true;
2707
2708	link_state = portstatus & USB_PORT_STAT_LINK_STATE;
2709	return link_state == USB_SS_PORT_LS_SS_INACTIVE
2710		|| link_state == USB_SS_PORT_LS_COMP_MOD;
2711}
2712
2713static int hub_port_wait_reset(struct usb_hub *hub, int port1,
2714			struct usb_device *udev, unsigned int delay, bool warm)
2715{
2716	int delay_time, ret;
2717	u16 portstatus;
2718	u16 portchange;
2719	u32 ext_portstatus = 0;
2720
2721	for (delay_time = 0;
2722			delay_time < HUB_RESET_TIMEOUT;
2723			delay_time += delay) {
2724		/* wait to give the device a chance to reset */
2725		msleep(delay);
2726
2727		/* read and decode port status */
2728		if (hub_is_superspeedplus(hub->hdev))
2729			ret = hub_ext_port_status(hub, port1,
2730						  HUB_EXT_PORT_STATUS,
2731						  &portstatus, &portchange,
2732						  &ext_portstatus);
2733		else
2734			ret = hub_port_status(hub, port1, &portstatus,
2735					      &portchange);
2736		if (ret < 0)
2737			return ret;
2738
2739		/* The port state is unknown until the reset completes. */
2740		if (!(portstatus & USB_PORT_STAT_RESET))
 
 
 
 
 
 
 
2741			break;
2742
2743		/* switch to the long delay after two short delay failures */
2744		if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
2745			delay = HUB_LONG_RESET_TIME;
2746
2747		dev_dbg(&hub->ports[port1 - 1]->dev,
2748				"not %sreset yet, waiting %dms\n",
2749				warm ? "warm " : "", delay);
2750	}
2751
2752	if ((portstatus & USB_PORT_STAT_RESET))
2753		return -EBUSY;
2754
2755	if (hub_port_warm_reset_required(hub, port1, portstatus))
2756		return -ENOTCONN;
2757
2758	/* Device went away? */
2759	if (!(portstatus & USB_PORT_STAT_CONNECTION))
2760		return -ENOTCONN;
2761
2762	/* bomb out completely if the connection bounced.  A USB 3.0
2763	 * connection may bounce if multiple warm resets were issued,
2764	 * but the device may have successfully re-connected. Ignore it.
2765	 */
2766	if (!hub_is_superspeed(hub->hdev) &&
2767			(portchange & USB_PORT_STAT_C_CONNECTION))
2768		return -ENOTCONN;
2769
2770	if (!(portstatus & USB_PORT_STAT_ENABLE))
2771		return -EBUSY;
2772
2773	if (!udev)
2774		return 0;
2775
2776	if (hub_is_wusb(hub))
2777		udev->speed = USB_SPEED_WIRELESS;
2778	else if (hub_is_superspeedplus(hub->hdev) &&
2779		 port_speed_is_ssp(hub->hdev, ext_portstatus &
2780				   USB_EXT_PORT_STAT_RX_SPEED_ID))
2781		udev->speed = USB_SPEED_SUPER_PLUS;
2782	else if (hub_is_superspeed(hub->hdev))
2783		udev->speed = USB_SPEED_SUPER;
2784	else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
2785		udev->speed = USB_SPEED_HIGH;
2786	else if (portstatus & USB_PORT_STAT_LOW_SPEED)
2787		udev->speed = USB_SPEED_LOW;
2788	else
2789		udev->speed = USB_SPEED_FULL;
2790	return 0;
2791}
2792
2793/* Handle port reset and port warm(BH) reset (for USB3 protocol ports) */
2794static int hub_port_reset(struct usb_hub *hub, int port1,
2795			struct usb_device *udev, unsigned int delay, bool warm)
2796{
2797	int i, status;
2798	u16 portchange, portstatus;
2799	struct usb_port *port_dev = hub->ports[port1 - 1];
2800
2801	if (!hub_is_superspeed(hub->hdev)) {
2802		if (warm) {
2803			dev_err(hub->intfdev, "only USB3 hub support "
2804						"warm reset\n");
2805			return -EINVAL;
2806		}
2807		/* Block EHCI CF initialization during the port reset.
2808		 * Some companion controllers don't like it when they mix.
2809		 */
2810		down_read(&ehci_cf_port_reset_rwsem);
2811	} else if (!warm) {
2812		/*
2813		 * If the caller hasn't explicitly requested a warm reset,
2814		 * double check and see if one is needed.
2815		 */
2816		if (hub_port_status(hub, port1, &portstatus, &portchange) == 0)
2817			if (hub_port_warm_reset_required(hub, port1,
2818							portstatus))
2819				warm = true;
2820	}
2821	clear_bit(port1, hub->warm_reset_bits);
2822
2823	/* Reset the port */
2824	for (i = 0; i < PORT_RESET_TRIES; i++) {
2825		status = set_port_feature(hub->hdev, port1, (warm ?
2826					USB_PORT_FEAT_BH_PORT_RESET :
2827					USB_PORT_FEAT_RESET));
2828		if (status == -ENODEV) {
2829			;	/* The hub is gone */
2830		} else if (status) {
2831			dev_err(&port_dev->dev,
2832					"cannot %sreset (err = %d)\n",
2833					warm ? "warm " : "", status);
2834		} else {
2835			status = hub_port_wait_reset(hub, port1, udev, delay,
2836								warm);
2837			if (status && status != -ENOTCONN && status != -ENODEV)
2838				dev_dbg(hub->intfdev,
2839						"port_wait_reset: err = %d\n",
2840						status);
2841		}
2842
2843		/* Check for disconnect or reset */
2844		if (status == 0 || status == -ENOTCONN || status == -ENODEV) {
2845			usb_clear_port_feature(hub->hdev, port1,
2846					USB_PORT_FEAT_C_RESET);
2847
2848			if (!hub_is_superspeed(hub->hdev))
2849				goto done;
2850
2851			usb_clear_port_feature(hub->hdev, port1,
2852					USB_PORT_FEAT_C_BH_PORT_RESET);
2853			usb_clear_port_feature(hub->hdev, port1,
2854					USB_PORT_FEAT_C_PORT_LINK_STATE);
2855			usb_clear_port_feature(hub->hdev, port1,
2856					USB_PORT_FEAT_C_CONNECTION);
2857
2858			/*
2859			 * If a USB 3.0 device migrates from reset to an error
2860			 * state, re-issue the warm reset.
2861			 */
2862			if (hub_port_status(hub, port1,
2863					&portstatus, &portchange) < 0)
2864				goto done;
2865
2866			if (!hub_port_warm_reset_required(hub, port1,
2867					portstatus))
2868				goto done;
2869
2870			/*
2871			 * If the port is in SS.Inactive or Compliance Mode, the
2872			 * hot or warm reset failed.  Try another warm reset.
2873			 */
2874			if (!warm) {
2875				dev_dbg(&port_dev->dev,
2876						"hot reset failed, warm reset\n");
2877				warm = true;
2878			}
2879		}
2880
2881		dev_dbg(&port_dev->dev,
2882				"not enabled, trying %sreset again...\n",
2883				warm ? "warm " : "");
2884		delay = HUB_LONG_RESET_TIME;
2885	}
2886
2887	dev_err(&port_dev->dev, "Cannot enable. Maybe the USB cable is bad?\n");
2888
2889done:
2890	if (status == 0) {
2891		/* TRSTRCY = 10 ms; plus some extra */
2892		msleep(10 + 40);
2893		if (udev) {
2894			struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2895
2896			update_devnum(udev, 0);
2897			/* The xHC may think the device is already reset,
2898			 * so ignore the status.
2899			 */
2900			if (hcd->driver->reset_device)
2901				hcd->driver->reset_device(hcd, udev);
2902
2903			usb_set_device_state(udev, USB_STATE_DEFAULT);
2904		}
2905	} else {
2906		if (udev)
2907			usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2908	}
2909
2910	if (!hub_is_superspeed(hub->hdev))
2911		up_read(&ehci_cf_port_reset_rwsem);
2912
2913	return status;
2914}
2915
2916/* Check if a port is power on */
2917static int port_is_power_on(struct usb_hub *hub, unsigned portstatus)
2918{
2919	int ret = 0;
2920
2921	if (hub_is_superspeed(hub->hdev)) {
2922		if (portstatus & USB_SS_PORT_STAT_POWER)
2923			ret = 1;
2924	} else {
2925		if (portstatus & USB_PORT_STAT_POWER)
2926			ret = 1;
2927	}
2928
2929	return ret;
2930}
2931
2932static void usb_lock_port(struct usb_port *port_dev)
2933		__acquires(&port_dev->status_lock)
2934{
2935	mutex_lock(&port_dev->status_lock);
2936	__acquire(&port_dev->status_lock);
2937}
2938
2939static void usb_unlock_port(struct usb_port *port_dev)
2940		__releases(&port_dev->status_lock)
2941{
2942	mutex_unlock(&port_dev->status_lock);
2943	__release(&port_dev->status_lock);
2944}
2945
2946#ifdef	CONFIG_PM
2947
2948/* Check if a port is suspended(USB2.0 port) or in U3 state(USB3.0 port) */
2949static int port_is_suspended(struct usb_hub *hub, unsigned portstatus)
2950{
2951	int ret = 0;
2952
2953	if (hub_is_superspeed(hub->hdev)) {
2954		if ((portstatus & USB_PORT_STAT_LINK_STATE)
2955				== USB_SS_PORT_LS_U3)
2956			ret = 1;
2957	} else {
2958		if (portstatus & USB_PORT_STAT_SUSPEND)
2959			ret = 1;
2960	}
2961
2962	return ret;
2963}
2964
2965/* Determine whether the device on a port is ready for a normal resume,
2966 * is ready for a reset-resume, or should be disconnected.
2967 */
2968static int check_port_resume_type(struct usb_device *udev,
2969		struct usb_hub *hub, int port1,
2970		int status, u16 portchange, u16 portstatus)
2971{
2972	struct usb_port *port_dev = hub->ports[port1 - 1];
2973	int retries = 3;
2974
2975 retry:
2976	/* Is a warm reset needed to recover the connection? */
2977	if (status == 0 && udev->reset_resume
2978		&& hub_port_warm_reset_required(hub, port1, portstatus)) {
2979		/* pass */;
2980	}
2981	/* Is the device still present? */
2982	else if (status || port_is_suspended(hub, portstatus) ||
2983			!port_is_power_on(hub, portstatus)) {
2984		if (status >= 0)
2985			status = -ENODEV;
2986	} else if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2987		if (retries--) {
2988			usleep_range(200, 300);
2989			status = hub_port_status(hub, port1, &portstatus,
2990							     &portchange);
2991			goto retry;
2992		}
2993		status = -ENODEV;
2994	}
2995
2996	/* Can't do a normal resume if the port isn't enabled,
2997	 * so try a reset-resume instead.
2998	 */
2999	else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
3000		if (udev->persist_enabled)
3001			udev->reset_resume = 1;
3002		else
3003			status = -ENODEV;
3004	}
3005
3006	if (status) {
3007		dev_dbg(&port_dev->dev, "status %04x.%04x after resume, %d\n",
3008				portchange, portstatus, status);
3009	} else if (udev->reset_resume) {
3010
3011		/* Late port handoff can set status-change bits */
3012		if (portchange & USB_PORT_STAT_C_CONNECTION)
3013			usb_clear_port_feature(hub->hdev, port1,
3014					USB_PORT_FEAT_C_CONNECTION);
3015		if (portchange & USB_PORT_STAT_C_ENABLE)
3016			usb_clear_port_feature(hub->hdev, port1,
3017					USB_PORT_FEAT_C_ENABLE);
3018	}
3019
3020	return status;
3021}
3022
3023int usb_disable_ltm(struct usb_device *udev)
3024{
3025	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3026
3027	/* Check if the roothub and device supports LTM. */
3028	if (!usb_device_supports_ltm(hcd->self.root_hub) ||
3029			!usb_device_supports_ltm(udev))
3030		return 0;
3031
3032	/* Clear Feature LTM Enable can only be sent if the device is
3033	 * configured.
3034	 */
3035	if (!udev->actconfig)
3036		return 0;
3037
3038	return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3039			USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
3040			USB_DEVICE_LTM_ENABLE, 0, NULL, 0,
3041			USB_CTRL_SET_TIMEOUT);
3042}
3043EXPORT_SYMBOL_GPL(usb_disable_ltm);
3044
3045void usb_enable_ltm(struct usb_device *udev)
3046{
3047	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3048
3049	/* Check if the roothub and device supports LTM. */
3050	if (!usb_device_supports_ltm(hcd->self.root_hub) ||
3051			!usb_device_supports_ltm(udev))
3052		return;
3053
3054	/* Set Feature LTM Enable can only be sent if the device is
3055	 * configured.
3056	 */
3057	if (!udev->actconfig)
3058		return;
3059
3060	usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3061			USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
3062			USB_DEVICE_LTM_ENABLE, 0, NULL, 0,
3063			USB_CTRL_SET_TIMEOUT);
3064}
3065EXPORT_SYMBOL_GPL(usb_enable_ltm);
3066
3067/*
3068 * usb_enable_remote_wakeup - enable remote wakeup for a device
3069 * @udev: target device
3070 *
3071 * For USB-2 devices: Set the device's remote wakeup feature.
3072 *
3073 * For USB-3 devices: Assume there's only one function on the device and
3074 * enable remote wake for the first interface.  FIXME if the interface
3075 * association descriptor shows there's more than one function.
3076 */
3077static int usb_enable_remote_wakeup(struct usb_device *udev)
3078{
3079	if (udev->speed < USB_SPEED_SUPER)
3080		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3081				USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
3082				USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0,
3083				USB_CTRL_SET_TIMEOUT);
3084	else
3085		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3086				USB_REQ_SET_FEATURE, USB_RECIP_INTERFACE,
3087				USB_INTRF_FUNC_SUSPEND,
3088				USB_INTRF_FUNC_SUSPEND_RW |
3089					USB_INTRF_FUNC_SUSPEND_LP,
3090				NULL, 0, USB_CTRL_SET_TIMEOUT);
3091}
3092
3093/*
3094 * usb_disable_remote_wakeup - disable remote wakeup for a device
3095 * @udev: target device
3096 *
3097 * For USB-2 devices: Clear the device's remote wakeup feature.
3098 *
3099 * For USB-3 devices: Assume there's only one function on the device and
3100 * disable remote wake for the first interface.  FIXME if the interface
3101 * association descriptor shows there's more than one function.
3102 */
3103static int usb_disable_remote_wakeup(struct usb_device *udev)
3104{
3105	if (udev->speed < USB_SPEED_SUPER)
3106		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3107				USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
3108				USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0,
3109				USB_CTRL_SET_TIMEOUT);
3110	else
3111		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3112				USB_REQ_CLEAR_FEATURE, USB_RECIP_INTERFACE,
3113				USB_INTRF_FUNC_SUSPEND,	0, NULL, 0,
3114				USB_CTRL_SET_TIMEOUT);
3115}
3116
3117/* Count of wakeup-enabled devices at or below udev */
3118static unsigned wakeup_enabled_descendants(struct usb_device *udev)
3119{
3120	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
3121
3122	return udev->do_remote_wakeup +
3123			(hub ? hub->wakeup_enabled_descendants : 0);
3124}
3125
3126/*
3127 * usb_port_suspend - suspend a usb device's upstream port
3128 * @udev: device that's no longer in active use, not a root hub
3129 * Context: must be able to sleep; device not locked; pm locks held
3130 *
3131 * Suspends a USB device that isn't in active use, conserving power.
3132 * Devices may wake out of a suspend, if anything important happens,
3133 * using the remote wakeup mechanism.  They may also be taken out of
3134 * suspend by the host, using usb_port_resume().  It's also routine
3135 * to disconnect devices while they are suspended.
3136 *
3137 * This only affects the USB hardware for a device; its interfaces
3138 * (and, for hubs, child devices) must already have been suspended.
3139 *
3140 * Selective port suspend reduces power; most suspended devices draw
3141 * less than 500 uA.  It's also used in OTG, along with remote wakeup.
3142 * All devices below the suspended port are also suspended.
3143 *
3144 * Devices leave suspend state when the host wakes them up.  Some devices
3145 * also support "remote wakeup", where the device can activate the USB
3146 * tree above them to deliver data, such as a keypress or packet.  In
3147 * some cases, this wakes the USB host.
3148 *
3149 * Suspending OTG devices may trigger HNP, if that's been enabled
3150 * between a pair of dual-role devices.  That will change roles, such
3151 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
3152 *
3153 * Devices on USB hub ports have only one "suspend" state, corresponding
3154 * to ACPI D2, "may cause the device to lose some context".
3155 * State transitions include:
3156 *
3157 *   - suspend, resume ... when the VBUS power link stays live
3158 *   - suspend, disconnect ... VBUS lost
3159 *
3160 * Once VBUS drop breaks the circuit, the port it's using has to go through
3161 * normal re-enumeration procedures, starting with enabling VBUS power.
3162 * Other than re-initializing the hub (plug/unplug, except for root hubs),
3163 * Linux (2.6) currently has NO mechanisms to initiate that:  no hub_wq
3164 * timer, no SRP, no requests through sysfs.
3165 *
3166 * If Runtime PM isn't enabled or used, non-SuperSpeed devices may not get
3167 * suspended until their bus goes into global suspend (i.e., the root
3168 * hub is suspended).  Nevertheless, we change @udev->state to
3169 * USB_STATE_SUSPENDED as this is the device's "logical" state.  The actual
3170 * upstream port setting is stored in @udev->port_is_suspended.
3171 *
3172 * Returns 0 on success, else negative errno.
3173 */
3174int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
3175{
3176	struct usb_hub	*hub = usb_hub_to_struct_hub(udev->parent);
3177	struct usb_port *port_dev = hub->ports[udev->portnum - 1];
3178	int		port1 = udev->portnum;
3179	int		status;
3180	bool		really_suspend = true;
3181
3182	usb_lock_port(port_dev);
3183
3184	/* enable remote wakeup when appropriate; this lets the device
3185	 * wake up the upstream hub (including maybe the root hub).
3186	 *
3187	 * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
3188	 * we don't explicitly enable it here.
3189	 */
3190	if (udev->do_remote_wakeup) {
3191		status = usb_enable_remote_wakeup(udev);
3192		if (status) {
3193			dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
3194					status);
3195			/* bail if autosuspend is requested */
3196			if (PMSG_IS_AUTO(msg))
3197				goto err_wakeup;
3198		}
3199	}
3200
3201	/* disable USB2 hardware LPM */
3202	if (udev->usb2_hw_lpm_enabled == 1)
3203		usb_set_usb2_hardware_lpm(udev, 0);
3204
3205	if (usb_disable_ltm(udev)) {
3206		dev_err(&udev->dev, "Failed to disable LTM before suspend\n.");
3207		status = -ENOMEM;
3208		if (PMSG_IS_AUTO(msg))
3209			goto err_ltm;
3210	}
3211	if (usb_unlocked_disable_lpm(udev)) {
3212		dev_err(&udev->dev, "Failed to disable LPM before suspend\n.");
3213		status = -ENOMEM;
3214		if (PMSG_IS_AUTO(msg))
3215			goto err_lpm3;
3216	}
3217
3218	/* see 7.1.7.6 */
3219	if (hub_is_superspeed(hub->hdev))
3220		status = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_U3);
3221
3222	/*
3223	 * For system suspend, we do not need to enable the suspend feature
3224	 * on individual USB-2 ports.  The devices will automatically go
3225	 * into suspend a few ms after the root hub stops sending packets.
3226	 * The USB 2.0 spec calls this "global suspend".
3227	 *
3228	 * However, many USB hubs have a bug: They don't relay wakeup requests
3229	 * from a downstream port if the port's suspend feature isn't on.
3230	 * Therefore we will turn on the suspend feature if udev or any of its
3231	 * descendants is enabled for remote wakeup.
3232	 */
3233	else if (PMSG_IS_AUTO(msg) || wakeup_enabled_descendants(udev) > 0)
3234		status = set_port_feature(hub->hdev, port1,
3235				USB_PORT_FEAT_SUSPEND);
3236	else {
3237		really_suspend = false;
3238		status = 0;
3239	}
3240	if (status) {
3241		dev_dbg(&port_dev->dev, "can't suspend, status %d\n", status);
3242
3243		/* Try to enable USB3 LPM and LTM again */
3244		usb_unlocked_enable_lpm(udev);
3245 err_lpm3:
3246		usb_enable_ltm(udev);
3247 err_ltm:
3248		/* Try to enable USB2 hardware LPM again */
3249		if (udev->usb2_hw_lpm_capable == 1)
3250			usb_set_usb2_hardware_lpm(udev, 1);
3251
3252		if (udev->do_remote_wakeup)
3253			(void) usb_disable_remote_wakeup(udev);
3254 err_wakeup:
3255
3256		/* System sleep transitions should never fail */
3257		if (!PMSG_IS_AUTO(msg))
3258			status = 0;
3259	} else {
3260		dev_dbg(&udev->dev, "usb %ssuspend, wakeup %d\n",
3261				(PMSG_IS_AUTO(msg) ? "auto-" : ""),
3262				udev->do_remote_wakeup);
3263		if (really_suspend) {
3264			udev->port_is_suspended = 1;
3265
3266			/* device has up to 10 msec to fully suspend */
3267			msleep(10);
3268		}
3269		usb_set_device_state(udev, USB_STATE_SUSPENDED);
3270	}
3271
3272	if (status == 0 && !udev->do_remote_wakeup && udev->persist_enabled
3273			&& test_and_clear_bit(port1, hub->child_usage_bits))
3274		pm_runtime_put_sync(&port_dev->dev);
3275
3276	usb_mark_last_busy(hub->hdev);
3277
3278	usb_unlock_port(port_dev);
3279	return status;
3280}
3281
3282/*
3283 * If the USB "suspend" state is in use (rather than "global suspend"),
3284 * many devices will be individually taken out of suspend state using
3285 * special "resume" signaling.  This routine kicks in shortly after
3286 * hardware resume signaling is finished, either because of selective
3287 * resume (by host) or remote wakeup (by device) ... now see what changed
3288 * in the tree that's rooted at this device.
3289 *
3290 * If @udev->reset_resume is set then the device is reset before the
3291 * status check is done.
3292 */
3293static int finish_port_resume(struct usb_device *udev)
3294{
3295	int	status = 0;
3296	u16	devstatus = 0;
3297
3298	/* caller owns the udev device lock */
3299	dev_dbg(&udev->dev, "%s\n",
3300		udev->reset_resume ? "finish reset-resume" : "finish resume");
3301
3302	/* usb ch9 identifies four variants of SUSPENDED, based on what
3303	 * state the device resumes to.  Linux currently won't see the
3304	 * first two on the host side; they'd be inside hub_port_init()
3305	 * during many timeouts, but hub_wq can't suspend until later.
3306	 */
3307	usb_set_device_state(udev, udev->actconfig
3308			? USB_STATE_CONFIGURED
3309			: USB_STATE_ADDRESS);
3310
3311	/* 10.5.4.5 says not to reset a suspended port if the attached
3312	 * device is enabled for remote wakeup.  Hence the reset
3313	 * operation is carried out here, after the port has been
3314	 * resumed.
3315	 */
3316	if (udev->reset_resume) {
3317		/*
3318		 * If the device morphs or switches modes when it is reset,
3319		 * we don't want to perform a reset-resume.  We'll fail the
3320		 * resume, which will cause a logical disconnect, and then
3321		 * the device will be rediscovered.
3322		 */
3323 retry_reset_resume:
3324		if (udev->quirks & USB_QUIRK_RESET)
3325			status = -ENODEV;
3326		else
3327			status = usb_reset_and_verify_device(udev);
3328	}
3329
3330	/* 10.5.4.5 says be sure devices in the tree are still there.
3331	 * For now let's assume the device didn't go crazy on resume,
3332	 * and device drivers will know about any resume quirks.
3333	 */
3334	if (status == 0) {
3335		devstatus = 0;
3336		status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
3337
3338		/* If a normal resume failed, try doing a reset-resume */
3339		if (status && !udev->reset_resume && udev->persist_enabled) {
3340			dev_dbg(&udev->dev, "retry with reset-resume\n");
3341			udev->reset_resume = 1;
3342			goto retry_reset_resume;
3343		}
3344	}
3345
3346	if (status) {
3347		dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
3348				status);
3349	/*
3350	 * There are a few quirky devices which violate the standard
3351	 * by claiming to have remote wakeup enabled after a reset,
3352	 * which crash if the feature is cleared, hence check for
3353	 * udev->reset_resume
3354	 */
3355	} else if (udev->actconfig && !udev->reset_resume) {
3356		if (udev->speed < USB_SPEED_SUPER) {
3357			if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
3358				status = usb_disable_remote_wakeup(udev);
3359		} else {
3360			status = usb_get_status(udev, USB_RECIP_INTERFACE, 0,
3361					&devstatus);
3362			if (!status && devstatus & (USB_INTRF_STAT_FUNC_RW_CAP
3363					| USB_INTRF_STAT_FUNC_RW))
3364				status = usb_disable_remote_wakeup(udev);
3365		}
3366
3367		if (status)
3368			dev_dbg(&udev->dev,
3369				"disable remote wakeup, status %d\n",
3370				status);
3371		status = 0;
3372	}
3373	return status;
3374}
3375
3376/*
3377 * There are some SS USB devices which take longer time for link training.
3378 * XHCI specs 4.19.4 says that when Link training is successful, port
3379 * sets CCS bit to 1. So if SW reads port status before successful link
3380 * training, then it will not find device to be present.
3381 * USB Analyzer log with such buggy devices show that in some cases
3382 * device switch on the RX termination after long delay of host enabling
3383 * the VBUS. In few other cases it has been seen that device fails to
3384 * negotiate link training in first attempt. It has been
3385 * reported till now that few devices take as long as 2000 ms to train
3386 * the link after host enabling its VBUS and termination. Following
3387 * routine implements a 2000 ms timeout for link training. If in a case
3388 * link trains before timeout, loop will exit earlier.
3389 *
3390 * There are also some 2.0 hard drive based devices and 3.0 thumb
3391 * drives that, when plugged into a 2.0 only port, take a long
3392 * time to set CCS after VBUS enable.
3393 *
3394 * FIXME: If a device was connected before suspend, but was removed
3395 * while system was asleep, then the loop in the following routine will
3396 * only exit at timeout.
3397 *
3398 * This routine should only be called when persist is enabled.
3399 */
3400static int wait_for_connected(struct usb_device *udev,
3401		struct usb_hub *hub, int *port1,
3402		u16 *portchange, u16 *portstatus)
3403{
3404	int status = 0, delay_ms = 0;
3405
3406	while (delay_ms < 2000) {
3407		if (status || *portstatus & USB_PORT_STAT_CONNECTION)
3408			break;
3409		msleep(20);
3410		delay_ms += 20;
3411		status = hub_port_status(hub, *port1, portstatus, portchange);
3412	}
3413	dev_dbg(&udev->dev, "Waited %dms for CONNECT\n", delay_ms);
3414	return status;
3415}
3416
3417/*
3418 * usb_port_resume - re-activate a suspended usb device's upstream port
3419 * @udev: device to re-activate, not a root hub
3420 * Context: must be able to sleep; device not locked; pm locks held
3421 *
3422 * This will re-activate the suspended device, increasing power usage
3423 * while letting drivers communicate again with its endpoints.
3424 * USB resume explicitly guarantees that the power session between
3425 * the host and the device is the same as it was when the device
3426 * suspended.
3427 *
3428 * If @udev->reset_resume is set then this routine won't check that the
3429 * port is still enabled.  Furthermore, finish_port_resume() above will
3430 * reset @udev.  The end result is that a broken power session can be
3431 * recovered and @udev will appear to persist across a loss of VBUS power.
3432 *
3433 * For example, if a host controller doesn't maintain VBUS suspend current
3434 * during a system sleep or is reset when the system wakes up, all the USB
3435 * power sessions below it will be broken.  This is especially troublesome
3436 * for mass-storage devices containing mounted filesystems, since the
3437 * device will appear to have disconnected and all the memory mappings
3438 * to it will be lost.  Using the USB_PERSIST facility, the device can be
3439 * made to appear as if it had not disconnected.
3440 *
3441 * This facility can be dangerous.  Although usb_reset_and_verify_device() makes
3442 * every effort to insure that the same device is present after the
3443 * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
3444 * quite possible for a device to remain unaltered but its media to be
3445 * changed.  If the user replaces a flash memory card while the system is
3446 * asleep, he will have only himself to blame when the filesystem on the
3447 * new card is corrupted and the system crashes.
3448 *
3449 * Returns 0 on success, else negative errno.
3450 */
3451int usb_port_resume(struct usb_device *udev, pm_message_t msg)
3452{
3453	struct usb_hub	*hub = usb_hub_to_struct_hub(udev->parent);
3454	struct usb_port *port_dev = hub->ports[udev->portnum  - 1];
3455	int		port1 = udev->portnum;
3456	int		status;
3457	u16		portchange, portstatus;
3458
3459	if (!test_and_set_bit(port1, hub->child_usage_bits)) {
3460		status = pm_runtime_get_sync(&port_dev->dev);
3461		if (status < 0) {
3462			dev_dbg(&udev->dev, "can't resume usb port, status %d\n",
3463					status);
3464			return status;
3465		}
3466	}
3467
3468	usb_lock_port(port_dev);
3469
3470	/* Skip the initial Clear-Suspend step for a remote wakeup */
3471	status = hub_port_status(hub, port1, &portstatus, &portchange);
3472	if (status == 0 && !port_is_suspended(hub, portstatus))
3473		goto SuspendCleared;
3474
3475	/* see 7.1.7.7; affects power usage, but not budgeting */
3476	if (hub_is_superspeed(hub->hdev))
3477		status = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_U0);
3478	else
3479		status = usb_clear_port_feature(hub->hdev,
3480				port1, USB_PORT_FEAT_SUSPEND);
3481	if (status) {
3482		dev_dbg(&port_dev->dev, "can't resume, status %d\n", status);
3483	} else {
3484		/* drive resume for USB_RESUME_TIMEOUT msec */
3485		dev_dbg(&udev->dev, "usb %sresume\n",
3486				(PMSG_IS_AUTO(msg) ? "auto-" : ""));
3487		msleep(USB_RESUME_TIMEOUT);
3488
3489		/* Virtual root hubs can trigger on GET_PORT_STATUS to
3490		 * stop resume signaling.  Then finish the resume
3491		 * sequence.
3492		 */
3493		status = hub_port_status(hub, port1, &portstatus, &portchange);
3494
3495		/* TRSMRCY = 10 msec */
3496		msleep(10);
3497	}
3498
3499 SuspendCleared:
3500	if (status == 0) {
3501		udev->port_is_suspended = 0;
3502		if (hub_is_superspeed(hub->hdev)) {
3503			if (portchange & USB_PORT_STAT_C_LINK_STATE)
3504				usb_clear_port_feature(hub->hdev, port1,
3505					USB_PORT_FEAT_C_PORT_LINK_STATE);
3506		} else {
3507			if (portchange & USB_PORT_STAT_C_SUSPEND)
3508				usb_clear_port_feature(hub->hdev, port1,
3509						USB_PORT_FEAT_C_SUSPEND);
3510		}
3511	}
3512
3513	if (udev->persist_enabled)
3514		status = wait_for_connected(udev, hub, &port1, &portchange,
3515				&portstatus);
3516
3517	status = check_port_resume_type(udev,
3518			hub, port1, status, portchange, portstatus);
3519	if (status == 0)
3520		status = finish_port_resume(udev);
3521	if (status < 0) {
3522		dev_dbg(&udev->dev, "can't resume, status %d\n", status);
3523		hub_port_logical_disconnect(hub, port1);
3524	} else  {
3525		/* Try to enable USB2 hardware LPM */
3526		if (udev->usb2_hw_lpm_capable == 1)
3527			usb_set_usb2_hardware_lpm(udev, 1);
3528
3529		/* Try to enable USB3 LTM and LPM */
3530		usb_enable_ltm(udev);
3531		usb_unlocked_enable_lpm(udev);
3532	}
3533
3534	usb_unlock_port(port_dev);
3535
3536	return status;
3537}
3538
3539int usb_remote_wakeup(struct usb_device *udev)
3540{
3541	int	status = 0;
3542
3543	usb_lock_device(udev);
3544	if (udev->state == USB_STATE_SUSPENDED) {
3545		dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
3546		status = usb_autoresume_device(udev);
3547		if (status == 0) {
3548			/* Let the drivers do their thing, then... */
3549			usb_autosuspend_device(udev);
3550		}
3551	}
3552	usb_unlock_device(udev);
3553	return status;
3554}
3555
3556/* Returns 1 if there was a remote wakeup and a connect status change. */
3557static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
3558		u16 portstatus, u16 portchange)
3559		__must_hold(&port_dev->status_lock)
3560{
3561	struct usb_port *port_dev = hub->ports[port - 1];
3562	struct usb_device *hdev;
3563	struct usb_device *udev;
3564	int connect_change = 0;
3565	int ret;
3566
3567	hdev = hub->hdev;
3568	udev = port_dev->child;
3569	if (!hub_is_superspeed(hdev)) {
3570		if (!(portchange & USB_PORT_STAT_C_SUSPEND))
3571			return 0;
3572		usb_clear_port_feature(hdev, port, USB_PORT_FEAT_C_SUSPEND);
3573	} else {
3574		if (!udev || udev->state != USB_STATE_SUSPENDED ||
3575				 (portstatus & USB_PORT_STAT_LINK_STATE) !=
3576				 USB_SS_PORT_LS_U0)
3577			return 0;
3578	}
3579
3580	if (udev) {
3581		/* TRSMRCY = 10 msec */
3582		msleep(10);
3583
3584		usb_unlock_port(port_dev);
3585		ret = usb_remote_wakeup(udev);
3586		usb_lock_port(port_dev);
3587		if (ret < 0)
3588			connect_change = 1;
3589	} else {
3590		ret = -ENODEV;
3591		hub_port_disable(hub, port, 1);
3592	}
3593	dev_dbg(&port_dev->dev, "resume, status %d\n", ret);
3594	return connect_change;
3595}
3596
3597static int check_ports_changed(struct usb_hub *hub)
3598{
3599	int port1;
3600
3601	for (port1 = 1; port1 <= hub->hdev->maxchild; ++port1) {
3602		u16 portstatus, portchange;
3603		int status;
3604
3605		status = hub_port_status(hub, port1, &portstatus, &portchange);
3606		if (!status && portchange)
3607			return 1;
3608	}
3609	return 0;
3610}
3611
3612static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
3613{
3614	struct usb_hub		*hub = usb_get_intfdata(intf);
3615	struct usb_device	*hdev = hub->hdev;
3616	unsigned		port1;
3617	int			status;
3618
3619	/*
3620	 * Warn if children aren't already suspended.
3621	 * Also, add up the number of wakeup-enabled descendants.
3622	 */
3623	hub->wakeup_enabled_descendants = 0;
3624	for (port1 = 1; port1 <= hdev->maxchild; port1++) {
3625		struct usb_port *port_dev = hub->ports[port1 - 1];
3626		struct usb_device *udev = port_dev->child;
3627
3628		if (udev && udev->can_submit) {
3629			dev_warn(&port_dev->dev, "device %s not suspended yet\n",
3630					dev_name(&udev->dev));
3631			if (PMSG_IS_AUTO(msg))
3632				return -EBUSY;
3633		}
3634		if (udev)
3635			hub->wakeup_enabled_descendants +=
3636					wakeup_enabled_descendants(udev);
3637	}
3638
3639	if (hdev->do_remote_wakeup && hub->quirk_check_port_auto_suspend) {
3640		/* check if there are changes pending on hub ports */
3641		if (check_ports_changed(hub)) {
3642			if (PMSG_IS_AUTO(msg))
3643				return -EBUSY;
3644			pm_wakeup_event(&hdev->dev, 2000);
3645		}
3646	}
3647
3648	if (hub_is_superspeed(hdev) && hdev->do_remote_wakeup) {
3649		/* Enable hub to send remote wakeup for all ports. */
3650		for (port1 = 1; port1 <= hdev->maxchild; port1++) {
3651			status = set_port_feature(hdev,
3652					port1 |
3653					USB_PORT_FEAT_REMOTE_WAKE_CONNECT |
3654					USB_PORT_FEAT_REMOTE_WAKE_DISCONNECT |
3655					USB_PORT_FEAT_REMOTE_WAKE_OVER_CURRENT,
3656					USB_PORT_FEAT_REMOTE_WAKE_MASK);
3657		}
3658	}
3659
3660	dev_dbg(&intf->dev, "%s\n", __func__);
3661
3662	/* stop hub_wq and related activity */
3663	hub_quiesce(hub, HUB_SUSPEND);
3664	return 0;
3665}
3666
3667static int hub_resume(struct usb_interface *intf)
3668{
3669	struct usb_hub *hub = usb_get_intfdata(intf);
3670
3671	dev_dbg(&intf->dev, "%s\n", __func__);
3672	hub_activate(hub, HUB_RESUME);
3673	return 0;
3674}
3675
3676static int hub_reset_resume(struct usb_interface *intf)
3677{
3678	struct usb_hub *hub = usb_get_intfdata(intf);
3679
3680	dev_dbg(&intf->dev, "%s\n", __func__);
3681	hub_activate(hub, HUB_RESET_RESUME);
3682	return 0;
3683}
3684
3685/**
3686 * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
3687 * @rhdev: struct usb_device for the root hub
3688 *
3689 * The USB host controller driver calls this function when its root hub
3690 * is resumed and Vbus power has been interrupted or the controller
3691 * has been reset.  The routine marks @rhdev as having lost power.
3692 * When the hub driver is resumed it will take notice and carry out
3693 * power-session recovery for all the "USB-PERSIST"-enabled child devices;
3694 * the others will be disconnected.
3695 */
3696void usb_root_hub_lost_power(struct usb_device *rhdev)
3697{
3698	dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
3699	rhdev->reset_resume = 1;
3700}
3701EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
3702
3703static const char * const usb3_lpm_names[]  = {
3704	"U0",
3705	"U1",
3706	"U2",
3707	"U3",
3708};
3709
3710/*
3711 * Send a Set SEL control transfer to the device, prior to enabling
3712 * device-initiated U1 or U2.  This lets the device know the exit latencies from
3713 * the time the device initiates a U1 or U2 exit, to the time it will receive a
3714 * packet from the host.
3715 *
3716 * This function will fail if the SEL or PEL values for udev are greater than
3717 * the maximum allowed values for the link state to be enabled.
3718 */
3719static int usb_req_set_sel(struct usb_device *udev, enum usb3_link_state state)
3720{
3721	struct usb_set_sel_req *sel_values;
3722	unsigned long long u1_sel;
3723	unsigned long long u1_pel;
3724	unsigned long long u2_sel;
3725	unsigned long long u2_pel;
3726	int ret;
3727
3728	if (udev->state != USB_STATE_CONFIGURED)
3729		return 0;
3730
3731	/* Convert SEL and PEL stored in ns to us */
3732	u1_sel = DIV_ROUND_UP(udev->u1_params.sel, 1000);
3733	u1_pel = DIV_ROUND_UP(udev->u1_params.pel, 1000);
3734	u2_sel = DIV_ROUND_UP(udev->u2_params.sel, 1000);
3735	u2_pel = DIV_ROUND_UP(udev->u2_params.pel, 1000);
3736
3737	/*
3738	 * Make sure that the calculated SEL and PEL values for the link
3739	 * state we're enabling aren't bigger than the max SEL/PEL
3740	 * value that will fit in the SET SEL control transfer.
3741	 * Otherwise the device would get an incorrect idea of the exit
3742	 * latency for the link state, and could start a device-initiated
3743	 * U1/U2 when the exit latencies are too high.
3744	 */
3745	if ((state == USB3_LPM_U1 &&
3746				(u1_sel > USB3_LPM_MAX_U1_SEL_PEL ||
3747				 u1_pel > USB3_LPM_MAX_U1_SEL_PEL)) ||
3748			(state == USB3_LPM_U2 &&
3749			 (u2_sel > USB3_LPM_MAX_U2_SEL_PEL ||
3750			  u2_pel > USB3_LPM_MAX_U2_SEL_PEL))) {
3751		dev_dbg(&udev->dev, "Device-initiated %s disabled due to long SEL %llu us or PEL %llu us\n",
3752				usb3_lpm_names[state], u1_sel, u1_pel);
3753		return -EINVAL;
3754	}
3755
3756	/*
3757	 * If we're enabling device-initiated LPM for one link state,
3758	 * but the other link state has a too high SEL or PEL value,
3759	 * just set those values to the max in the Set SEL request.
3760	 */
3761	if (u1_sel > USB3_LPM_MAX_U1_SEL_PEL)
3762		u1_sel = USB3_LPM_MAX_U1_SEL_PEL;
3763
3764	if (u1_pel > USB3_LPM_MAX_U1_SEL_PEL)
3765		u1_pel = USB3_LPM_MAX_U1_SEL_PEL;
3766
3767	if (u2_sel > USB3_LPM_MAX_U2_SEL_PEL)
3768		u2_sel = USB3_LPM_MAX_U2_SEL_PEL;
3769
3770	if (u2_pel > USB3_LPM_MAX_U2_SEL_PEL)
3771		u2_pel = USB3_LPM_MAX_U2_SEL_PEL;
3772
3773	/*
3774	 * usb_enable_lpm() can be called as part of a failed device reset,
3775	 * which may be initiated by an error path of a mass storage driver.
3776	 * Therefore, use GFP_NOIO.
3777	 */
3778	sel_values = kmalloc(sizeof *(sel_values), GFP_NOIO);
3779	if (!sel_values)
3780		return -ENOMEM;
3781
3782	sel_values->u1_sel = u1_sel;
3783	sel_values->u1_pel = u1_pel;
3784	sel_values->u2_sel = cpu_to_le16(u2_sel);
3785	sel_values->u2_pel = cpu_to_le16(u2_pel);
3786
3787	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3788			USB_REQ_SET_SEL,
3789			USB_RECIP_DEVICE,
3790			0, 0,
3791			sel_values, sizeof *(sel_values),
3792			USB_CTRL_SET_TIMEOUT);
3793	kfree(sel_values);
3794	return ret;
3795}
3796
3797/*
3798 * Enable or disable device-initiated U1 or U2 transitions.
3799 */
3800static int usb_set_device_initiated_lpm(struct usb_device *udev,
3801		enum usb3_link_state state, bool enable)
3802{
3803	int ret;
3804	int feature;
3805
3806	switch (state) {
3807	case USB3_LPM_U1:
3808		feature = USB_DEVICE_U1_ENABLE;
3809		break;
3810	case USB3_LPM_U2:
3811		feature = USB_DEVICE_U2_ENABLE;
3812		break;
3813	default:
3814		dev_warn(&udev->dev, "%s: Can't %s non-U1 or U2 state.\n",
3815				__func__, enable ? "enable" : "disable");
3816		return -EINVAL;
3817	}
3818
3819	if (udev->state != USB_STATE_CONFIGURED) {
3820		dev_dbg(&udev->dev, "%s: Can't %s %s state "
3821				"for unconfigured device.\n",
3822				__func__, enable ? "enable" : "disable",
3823				usb3_lpm_names[state]);
3824		return 0;
3825	}
3826
3827	if (enable) {
3828		/*
3829		 * Now send the control transfer to enable device-initiated LPM
3830		 * for either U1 or U2.
3831		 */
3832		ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3833				USB_REQ_SET_FEATURE,
3834				USB_RECIP_DEVICE,
3835				feature,
3836				0, NULL, 0,
3837				USB_CTRL_SET_TIMEOUT);
3838	} else {
3839		ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3840				USB_REQ_CLEAR_FEATURE,
3841				USB_RECIP_DEVICE,
3842				feature,
3843				0, NULL, 0,
3844				USB_CTRL_SET_TIMEOUT);
3845	}
3846	if (ret < 0) {
3847		dev_warn(&udev->dev, "%s of device-initiated %s failed.\n",
3848				enable ? "Enable" : "Disable",
3849				usb3_lpm_names[state]);
3850		return -EBUSY;
3851	}
3852	return 0;
3853}
3854
3855static int usb_set_lpm_timeout(struct usb_device *udev,
3856		enum usb3_link_state state, int timeout)
3857{
3858	int ret;
3859	int feature;
3860
3861	switch (state) {
3862	case USB3_LPM_U1:
3863		feature = USB_PORT_FEAT_U1_TIMEOUT;
3864		break;
3865	case USB3_LPM_U2:
3866		feature = USB_PORT_FEAT_U2_TIMEOUT;
3867		break;
3868	default:
3869		dev_warn(&udev->dev, "%s: Can't set timeout for non-U1 or U2 state.\n",
3870				__func__);
3871		return -EINVAL;
3872	}
3873
3874	if (state == USB3_LPM_U1 && timeout > USB3_LPM_U1_MAX_TIMEOUT &&
3875			timeout != USB3_LPM_DEVICE_INITIATED) {
3876		dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x, "
3877				"which is a reserved value.\n",
3878				usb3_lpm_names[state], timeout);
3879		return -EINVAL;
3880	}
3881
3882	ret = set_port_feature(udev->parent,
3883			USB_PORT_LPM_TIMEOUT(timeout) | udev->portnum,
3884			feature);
3885	if (ret < 0) {
3886		dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x,"
3887				"error code %i\n", usb3_lpm_names[state],
3888				timeout, ret);
3889		return -EBUSY;
3890	}
3891	if (state == USB3_LPM_U1)
3892		udev->u1_params.timeout = timeout;
3893	else
3894		udev->u2_params.timeout = timeout;
3895	return 0;
3896}
3897
3898/*
3899 * Enable the hub-initiated U1/U2 idle timeouts, and enable device-initiated
3900 * U1/U2 entry.
3901 *
3902 * We will attempt to enable U1 or U2, but there are no guarantees that the
3903 * control transfers to set the hub timeout or enable device-initiated U1/U2
3904 * will be successful.
3905 *
3906 * If we cannot set the parent hub U1/U2 timeout, we attempt to let the xHCI
3907 * driver know about it.  If that call fails, it should be harmless, and just
3908 * take up more slightly more bus bandwidth for unnecessary U1/U2 exit latency.
3909 */
3910static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
3911		enum usb3_link_state state)
3912{
3913	int timeout, ret;
3914	__u8 u1_mel = udev->bos->ss_cap->bU1devExitLat;
3915	__le16 u2_mel = udev->bos->ss_cap->bU2DevExitLat;
3916
3917	/* If the device says it doesn't have *any* exit latency to come out of
3918	 * U1 or U2, it's probably lying.  Assume it doesn't implement that link
3919	 * state.
3920	 */
3921	if ((state == USB3_LPM_U1 && u1_mel == 0) ||
3922			(state == USB3_LPM_U2 && u2_mel == 0))
3923		return;
3924
3925	/*
3926	 * First, let the device know about the exit latencies
3927	 * associated with the link state we're about to enable.
3928	 */
3929	ret = usb_req_set_sel(udev, state);
3930	if (ret < 0) {
3931		dev_warn(&udev->dev, "Set SEL for device-initiated %s failed.\n",
3932				usb3_lpm_names[state]);
3933		return;
3934	}
3935
3936	/* We allow the host controller to set the U1/U2 timeout internally
3937	 * first, so that it can change its schedule to account for the
3938	 * additional latency to send data to a device in a lower power
3939	 * link state.
3940	 */
3941	timeout = hcd->driver->enable_usb3_lpm_timeout(hcd, udev, state);
3942
3943	/* xHCI host controller doesn't want to enable this LPM state. */
3944	if (timeout == 0)
3945		return;
3946
3947	if (timeout < 0) {
3948		dev_warn(&udev->dev, "Could not enable %s link state, "
3949				"xHCI error %i.\n", usb3_lpm_names[state],
3950				timeout);
3951		return;
3952	}
3953
3954	if (usb_set_lpm_timeout(udev, state, timeout)) {
3955		/* If we can't set the parent hub U1/U2 timeout,
3956		 * device-initiated LPM won't be allowed either, so let the xHCI
3957		 * host know that this link state won't be enabled.
3958		 */
3959		hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
3960	} else {
3961		/* Only a configured device will accept the Set Feature
3962		 * U1/U2_ENABLE
3963		 */
3964		if (udev->actconfig)
3965			usb_set_device_initiated_lpm(udev, state, true);
3966
3967		/* As soon as usb_set_lpm_timeout(timeout) returns 0, the
3968		 * hub-initiated LPM is enabled. Thus, LPM is enabled no
3969		 * matter the result of usb_set_device_initiated_lpm().
3970		 * The only difference is whether device is able to initiate
3971		 * LPM.
3972		 */
3973		if (state == USB3_LPM_U1)
3974			udev->usb3_lpm_u1_enabled = 1;
3975		else if (state == USB3_LPM_U2)
3976			udev->usb3_lpm_u2_enabled = 1;
3977	}
3978}
3979
3980/*
3981 * Disable the hub-initiated U1/U2 idle timeouts, and disable device-initiated
3982 * U1/U2 entry.
3983 *
3984 * If this function returns -EBUSY, the parent hub will still allow U1/U2 entry.
3985 * If zero is returned, the parent will not allow the link to go into U1/U2.
3986 *
3987 * If zero is returned, device-initiated U1/U2 entry may still be enabled, but
3988 * it won't have an effect on the bus link state because the parent hub will
3989 * still disallow device-initiated U1/U2 entry.
3990 *
3991 * If zero is returned, the xHCI host controller may still think U1/U2 entry is
3992 * possible.  The result will be slightly more bus bandwidth will be taken up
3993 * (to account for U1/U2 exit latency), but it should be harmless.
3994 */
3995static int usb_disable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
3996		enum usb3_link_state state)
3997{
3998	switch (state) {
3999	case USB3_LPM_U1:
4000	case USB3_LPM_U2:
4001		break;
4002	default:
4003		dev_warn(&udev->dev, "%s: Can't disable non-U1 or U2 state.\n",
4004				__func__);
4005		return -EINVAL;
4006	}
4007
4008	if (usb_set_lpm_timeout(udev, state, 0))
4009		return -EBUSY;
4010
4011	usb_set_device_initiated_lpm(udev, state, false);
4012
4013	if (hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state))
4014		dev_warn(&udev->dev, "Could not disable xHCI %s timeout, "
4015				"bus schedule bandwidth may be impacted.\n",
4016				usb3_lpm_names[state]);
4017
4018	/* As soon as usb_set_lpm_timeout(0) return 0, hub initiated LPM
4019	 * is disabled. Hub will disallows link to enter U1/U2 as well,
4020	 * even device is initiating LPM. Hence LPM is disabled if hub LPM
4021	 * timeout set to 0, no matter device-initiated LPM is disabled or
4022	 * not.
4023	 */
4024	if (state == USB3_LPM_U1)
4025		udev->usb3_lpm_u1_enabled = 0;
4026	else if (state == USB3_LPM_U2)
4027		udev->usb3_lpm_u2_enabled = 0;
4028
4029	return 0;
4030}
4031
4032/*
4033 * Disable hub-initiated and device-initiated U1 and U2 entry.
4034 * Caller must own the bandwidth_mutex.
4035 *
4036 * This will call usb_enable_lpm() on failure, which will decrement
4037 * lpm_disable_count, and will re-enable LPM if lpm_disable_count reaches zero.
4038 */
4039int usb_disable_lpm(struct usb_device *udev)
4040{
4041	struct usb_hcd *hcd;
4042
4043	if (!udev || !udev->parent ||
4044			udev->speed < USB_SPEED_SUPER ||
4045			!udev->lpm_capable ||
4046			udev->state < USB_STATE_DEFAULT)
4047		return 0;
4048
4049	hcd = bus_to_hcd(udev->bus);
4050	if (!hcd || !hcd->driver->disable_usb3_lpm_timeout)
4051		return 0;
4052
4053	udev->lpm_disable_count++;
4054	if ((udev->u1_params.timeout == 0 && udev->u2_params.timeout == 0))
4055		return 0;
4056
4057	/* If LPM is enabled, attempt to disable it. */
4058	if (usb_disable_link_state(hcd, udev, USB3_LPM_U1))
4059		goto enable_lpm;
4060	if (usb_disable_link_state(hcd, udev, USB3_LPM_U2))
4061		goto enable_lpm;
4062
4063	return 0;
4064
4065enable_lpm:
4066	usb_enable_lpm(udev);
4067	return -EBUSY;
4068}
4069EXPORT_SYMBOL_GPL(usb_disable_lpm);
4070
4071/* Grab the bandwidth_mutex before calling usb_disable_lpm() */
4072int usb_unlocked_disable_lpm(struct usb_device *udev)
4073{
4074	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4075	int ret;
4076
4077	if (!hcd)
4078		return -EINVAL;
4079
4080	mutex_lock(hcd->bandwidth_mutex);
4081	ret = usb_disable_lpm(udev);
4082	mutex_unlock(hcd->bandwidth_mutex);
4083
4084	return ret;
4085}
4086EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
4087
4088/*
4089 * Attempt to enable device-initiated and hub-initiated U1 and U2 entry.  The
4090 * xHCI host policy may prevent U1 or U2 from being enabled.
4091 *
4092 * Other callers may have disabled link PM, so U1 and U2 entry will be disabled
4093 * until the lpm_disable_count drops to zero.  Caller must own the
4094 * bandwidth_mutex.
4095 */
4096void usb_enable_lpm(struct usb_device *udev)
4097{
4098	struct usb_hcd *hcd;
4099	struct usb_hub *hub;
4100	struct usb_port *port_dev;
4101
4102	if (!udev || !udev->parent ||
4103			udev->speed < USB_SPEED_SUPER ||
4104			!udev->lpm_capable ||
4105			udev->state < USB_STATE_DEFAULT)
4106		return;
4107
4108	udev->lpm_disable_count--;
4109	hcd = bus_to_hcd(udev->bus);
4110	/* Double check that we can both enable and disable LPM.
4111	 * Device must be configured to accept set feature U1/U2 timeout.
4112	 */
4113	if (!hcd || !hcd->driver->enable_usb3_lpm_timeout ||
4114			!hcd->driver->disable_usb3_lpm_timeout)
4115		return;
4116
4117	if (udev->lpm_disable_count > 0)
4118		return;
4119
4120	hub = usb_hub_to_struct_hub(udev->parent);
4121	if (!hub)
4122		return;
4123
4124	port_dev = hub->ports[udev->portnum - 1];
4125
4126	if (port_dev->usb3_lpm_u1_permit)
4127		usb_enable_link_state(hcd, udev, USB3_LPM_U1);
4128
4129	if (port_dev->usb3_lpm_u2_permit)
4130		usb_enable_link_state(hcd, udev, USB3_LPM_U2);
4131}
4132EXPORT_SYMBOL_GPL(usb_enable_lpm);
4133
4134/* Grab the bandwidth_mutex before calling usb_enable_lpm() */
4135void usb_unlocked_enable_lpm(struct usb_device *udev)
4136{
4137	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4138
4139	if (!hcd)
4140		return;
4141
4142	mutex_lock(hcd->bandwidth_mutex);
4143	usb_enable_lpm(udev);
4144	mutex_unlock(hcd->bandwidth_mutex);
4145}
4146EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
4147
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4148
4149#else	/* CONFIG_PM */
4150
4151#define hub_suspend		NULL
4152#define hub_resume		NULL
4153#define hub_reset_resume	NULL
4154
 
 
 
4155int usb_disable_lpm(struct usb_device *udev)
4156{
4157	return 0;
4158}
4159EXPORT_SYMBOL_GPL(usb_disable_lpm);
4160
4161void usb_enable_lpm(struct usb_device *udev) { }
4162EXPORT_SYMBOL_GPL(usb_enable_lpm);
4163
4164int usb_unlocked_disable_lpm(struct usb_device *udev)
4165{
4166	return 0;
4167}
4168EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
4169
4170void usb_unlocked_enable_lpm(struct usb_device *udev) { }
4171EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
4172
4173int usb_disable_ltm(struct usb_device *udev)
4174{
4175	return 0;
4176}
4177EXPORT_SYMBOL_GPL(usb_disable_ltm);
4178
4179void usb_enable_ltm(struct usb_device *udev) { }
4180EXPORT_SYMBOL_GPL(usb_enable_ltm);
4181
4182static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
4183		u16 portstatus, u16 portchange)
4184{
4185	return 0;
4186}
4187
4188#endif	/* CONFIG_PM */
4189
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4190
4191/* USB 2.0 spec, 7.1.7.3 / fig 7-29:
4192 *
4193 * Between connect detection and reset signaling there must be a delay
4194 * of 100ms at least for debounce and power-settling.  The corresponding
4195 * timer shall restart whenever the downstream port detects a disconnect.
4196 *
4197 * Apparently there are some bluetooth and irda-dongles and a number of
4198 * low-speed devices for which this debounce period may last over a second.
4199 * Not covered by the spec - but easy to deal with.
4200 *
4201 * This implementation uses a 1500ms total debounce timeout; if the
4202 * connection isn't stable by then it returns -ETIMEDOUT.  It checks
4203 * every 25ms for transient disconnects.  When the port status has been
4204 * unchanged for 100ms it returns the port status.
4205 */
4206int hub_port_debounce(struct usb_hub *hub, int port1, bool must_be_connected)
4207{
4208	int ret;
4209	u16 portchange, portstatus;
4210	unsigned connection = 0xffff;
4211	int total_time, stable_time = 0;
4212	struct usb_port *port_dev = hub->ports[port1 - 1];
4213
4214	for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
4215		ret = hub_port_status(hub, port1, &portstatus, &portchange);
4216		if (ret < 0)
4217			return ret;
4218
4219		if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
4220		     (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
4221			if (!must_be_connected ||
4222			     (connection == USB_PORT_STAT_CONNECTION))
4223				stable_time += HUB_DEBOUNCE_STEP;
4224			if (stable_time >= HUB_DEBOUNCE_STABLE)
4225				break;
4226		} else {
4227			stable_time = 0;
4228			connection = portstatus & USB_PORT_STAT_CONNECTION;
4229		}
4230
4231		if (portchange & USB_PORT_STAT_C_CONNECTION) {
4232			usb_clear_port_feature(hub->hdev, port1,
4233					USB_PORT_FEAT_C_CONNECTION);
4234		}
4235
4236		if (total_time >= HUB_DEBOUNCE_TIMEOUT)
4237			break;
4238		msleep(HUB_DEBOUNCE_STEP);
4239	}
4240
4241	dev_dbg(&port_dev->dev, "debounce total %dms stable %dms status 0x%x\n",
4242			total_time, stable_time, portstatus);
4243
4244	if (stable_time < HUB_DEBOUNCE_STABLE)
4245		return -ETIMEDOUT;
4246	return portstatus;
4247}
4248
4249void usb_ep0_reinit(struct usb_device *udev)
4250{
4251	usb_disable_endpoint(udev, 0 + USB_DIR_IN, true);
4252	usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true);
4253	usb_enable_endpoint(udev, &udev->ep0, true);
4254}
4255EXPORT_SYMBOL_GPL(usb_ep0_reinit);
4256
4257#define usb_sndaddr0pipe()	(PIPE_CONTROL << 30)
4258#define usb_rcvaddr0pipe()	((PIPE_CONTROL << 30) | USB_DIR_IN)
4259
4260static int hub_set_address(struct usb_device *udev, int devnum)
4261{
4262	int retval;
4263	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4264
4265	/*
4266	 * The host controller will choose the device address,
4267	 * instead of the core having chosen it earlier
4268	 */
4269	if (!hcd->driver->address_device && devnum <= 1)
4270		return -EINVAL;
4271	if (udev->state == USB_STATE_ADDRESS)
4272		return 0;
4273	if (udev->state != USB_STATE_DEFAULT)
4274		return -EINVAL;
4275	if (hcd->driver->address_device)
4276		retval = hcd->driver->address_device(hcd, udev);
4277	else
4278		retval = usb_control_msg(udev, usb_sndaddr0pipe(),
4279				USB_REQ_SET_ADDRESS, 0, devnum, 0,
4280				NULL, 0, USB_CTRL_SET_TIMEOUT);
4281	if (retval == 0) {
4282		update_devnum(udev, devnum);
4283		/* Device now using proper address. */
4284		usb_set_device_state(udev, USB_STATE_ADDRESS);
4285		usb_ep0_reinit(udev);
4286	}
4287	return retval;
4288}
4289
4290/*
4291 * There are reports of USB 3.0 devices that say they support USB 2.0 Link PM
4292 * when they're plugged into a USB 2.0 port, but they don't work when LPM is
4293 * enabled.
4294 *
4295 * Only enable USB 2.0 Link PM if the port is internal (hardwired), or the
4296 * device says it supports the new USB 2.0 Link PM errata by setting the BESL
4297 * support bit in the BOS descriptor.
4298 */
4299static void hub_set_initial_usb2_lpm_policy(struct usb_device *udev)
4300{
4301	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
4302	int connect_type = USB_PORT_CONNECT_TYPE_UNKNOWN;
4303
4304	if (!udev->usb2_hw_lpm_capable)
4305		return;
4306
4307	if (hub)
4308		connect_type = hub->ports[udev->portnum - 1]->connect_type;
4309
4310	if ((udev->bos->ext_cap->bmAttributes & cpu_to_le32(USB_BESL_SUPPORT)) ||
4311			connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
4312		udev->usb2_hw_lpm_allowed = 1;
4313		usb_set_usb2_hardware_lpm(udev, 1);
4314	}
4315}
4316
4317static int hub_enable_device(struct usb_device *udev)
4318{
4319	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4320
4321	if (!hcd->driver->enable_device)
4322		return 0;
4323	if (udev->state == USB_STATE_ADDRESS)
4324		return 0;
4325	if (udev->state != USB_STATE_DEFAULT)
4326		return -EINVAL;
4327
4328	return hcd->driver->enable_device(hcd, udev);
4329}
4330
4331/* Reset device, (re)assign address, get device descriptor.
4332 * Device connection must be stable, no more debouncing needed.
4333 * Returns device in USB_STATE_ADDRESS, except on error.
4334 *
4335 * If this is called for an already-existing device (as part of
4336 * usb_reset_and_verify_device), the caller must own the device lock and
4337 * the port lock.  For a newly detected device that is not accessible
4338 * through any global pointers, it's not necessary to lock the device,
4339 * but it is still necessary to lock the port.
4340 */
4341static int
4342hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1,
4343		int retry_counter)
4344{
4345	struct usb_device	*hdev = hub->hdev;
4346	struct usb_hcd		*hcd = bus_to_hcd(hdev->bus);
4347	int			retries, operations, retval, i;
4348	unsigned		delay = HUB_SHORT_RESET_TIME;
4349	enum usb_device_speed	oldspeed = udev->speed;
4350	const char		*speed;
4351	int			devnum = udev->devnum;
4352
4353	/* root hub ports have a slightly longer reset period
4354	 * (from USB 2.0 spec, section 7.1.7.5)
4355	 */
4356	if (!hdev->parent) {
4357		delay = HUB_ROOT_RESET_TIME;
4358		if (port1 == hdev->bus->otg_port)
4359			hdev->bus->b_hnp_enable = 0;
4360	}
4361
4362	/* Some low speed devices have problems with the quick delay, so */
4363	/*  be a bit pessimistic with those devices. RHbug #23670 */
4364	if (oldspeed == USB_SPEED_LOW)
4365		delay = HUB_LONG_RESET_TIME;
4366
4367	mutex_lock(&hdev->bus->usb_address0_mutex);
4368
4369	/* Reset the device; full speed may morph to high speed */
4370	/* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */
4371	retval = hub_port_reset(hub, port1, udev, delay, false);
4372	if (retval < 0)		/* error or disconnect */
4373		goto fail;
4374	/* success, speed is known */
4375
4376	retval = -ENODEV;
4377
4378	/* Don't allow speed changes at reset, except usb 3.0 to faster */
4379	if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed &&
4380	    !(oldspeed == USB_SPEED_SUPER && udev->speed > oldspeed)) {
4381		dev_dbg(&udev->dev, "device reset changed speed!\n");
4382		goto fail;
4383	}
4384	oldspeed = udev->speed;
4385
4386	/* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
4387	 * it's fixed size except for full speed devices.
4388	 * For Wireless USB devices, ep0 max packet is always 512 (tho
4389	 * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
4390	 */
4391	switch (udev->speed) {
4392	case USB_SPEED_SUPER_PLUS:
4393	case USB_SPEED_SUPER:
4394	case USB_SPEED_WIRELESS:	/* fixed at 512 */
4395		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
4396		break;
4397	case USB_SPEED_HIGH:		/* fixed at 64 */
4398		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
4399		break;
4400	case USB_SPEED_FULL:		/* 8, 16, 32, or 64 */
4401		/* to determine the ep0 maxpacket size, try to read
4402		 * the device descriptor to get bMaxPacketSize0 and
4403		 * then correct our initial guess.
4404		 */
4405		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
4406		break;
4407	case USB_SPEED_LOW:		/* fixed at 8 */
4408		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(8);
4409		break;
4410	default:
4411		goto fail;
4412	}
4413
4414	if (udev->speed == USB_SPEED_WIRELESS)
4415		speed = "variable speed Wireless";
4416	else
4417		speed = usb_speed_string(udev->speed);
4418
4419	if (udev->speed < USB_SPEED_SUPER)
4420		dev_info(&udev->dev,
4421				"%s %s USB device number %d using %s\n",
4422				(udev->config) ? "reset" : "new", speed,
4423				devnum, udev->bus->controller->driver->name);
4424
4425	/* Set up TT records, if needed  */
4426	if (hdev->tt) {
4427		udev->tt = hdev->tt;
4428		udev->ttport = hdev->ttport;
4429	} else if (udev->speed != USB_SPEED_HIGH
4430			&& hdev->speed == USB_SPEED_HIGH) {
4431		if (!hub->tt.hub) {
4432			dev_err(&udev->dev, "parent hub has no TT\n");
4433			retval = -EINVAL;
4434			goto fail;
4435		}
4436		udev->tt = &hub->tt;
4437		udev->ttport = port1;
4438	}
4439
4440	/* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
4441	 * Because device hardware and firmware is sometimes buggy in
4442	 * this area, and this is how Linux has done it for ages.
4443	 * Change it cautiously.
4444	 *
4445	 * NOTE:  If use_new_scheme() is true we will start by issuing
4446	 * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
4447	 * so it may help with some non-standards-compliant devices.
4448	 * Otherwise we start with SET_ADDRESS and then try to read the
4449	 * first 8 bytes of the device descriptor to get the ep0 maxpacket
4450	 * value.
4451	 */
4452	for (retries = 0; retries < GET_DESCRIPTOR_TRIES; (++retries, msleep(100))) {
4453		bool did_new_scheme = false;
4454
4455		if (use_new_scheme(udev, retry_counter)) {
4456			struct usb_device_descriptor *buf;
4457			int r = 0;
4458
4459			did_new_scheme = true;
4460			retval = hub_enable_device(udev);
4461			if (retval < 0) {
4462				dev_err(&udev->dev,
4463					"hub failed to enable device, error %d\n",
4464					retval);
4465				goto fail;
4466			}
4467
4468#define GET_DESCRIPTOR_BUFSIZE	64
4469			buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
4470			if (!buf) {
4471				retval = -ENOMEM;
4472				continue;
4473			}
4474
4475			/* Retry on all errors; some devices are flakey.
4476			 * 255 is for WUSB devices, we actually need to use
4477			 * 512 (WUSB1.0[4.8.1]).
4478			 */
4479			for (operations = 0; operations < 3; ++operations) {
4480				buf->bMaxPacketSize0 = 0;
4481				r = usb_control_msg(udev, usb_rcvaddr0pipe(),
4482					USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
4483					USB_DT_DEVICE << 8, 0,
4484					buf, GET_DESCRIPTOR_BUFSIZE,
4485					initial_descriptor_timeout);
4486				switch (buf->bMaxPacketSize0) {
4487				case 8: case 16: case 32: case 64: case 255:
4488					if (buf->bDescriptorType ==
4489							USB_DT_DEVICE) {
4490						r = 0;
4491						break;
4492					}
4493					/* FALL THROUGH */
4494				default:
4495					if (r == 0)
4496						r = -EPROTO;
4497					break;
4498				}
4499				/*
4500				 * Some devices time out if they are powered on
4501				 * when already connected. They need a second
4502				 * reset. But only on the first attempt,
4503				 * lest we get into a time out/reset loop
4504				 */
4505				if (r == 0  || (r == -ETIMEDOUT && retries == 0))
4506					break;
4507			}
4508			udev->descriptor.bMaxPacketSize0 =
4509					buf->bMaxPacketSize0;
4510			kfree(buf);
4511
4512			retval = hub_port_reset(hub, port1, udev, delay, false);
4513			if (retval < 0)		/* error or disconnect */
4514				goto fail;
4515			if (oldspeed != udev->speed) {
4516				dev_dbg(&udev->dev,
4517					"device reset changed speed!\n");
4518				retval = -ENODEV;
4519				goto fail;
4520			}
4521			if (r) {
4522				if (r != -ENODEV)
4523					dev_err(&udev->dev, "device descriptor read/64, error %d\n",
4524							r);
4525				retval = -EMSGSIZE;
4526				continue;
4527			}
4528#undef GET_DESCRIPTOR_BUFSIZE
4529		}
4530
4531		/*
4532		 * If device is WUSB, we already assigned an
4533		 * unauthorized address in the Connect Ack sequence;
4534		 * authorization will assign the final address.
4535		 */
4536		if (udev->wusb == 0) {
4537			for (operations = 0; operations < SET_ADDRESS_TRIES; ++operations) {
4538				retval = hub_set_address(udev, devnum);
4539				if (retval >= 0)
4540					break;
4541				msleep(200);
4542			}
4543			if (retval < 0) {
4544				if (retval != -ENODEV)
4545					dev_err(&udev->dev, "device not accepting address %d, error %d\n",
4546							devnum, retval);
4547				goto fail;
4548			}
4549			if (udev->speed >= USB_SPEED_SUPER) {
4550				devnum = udev->devnum;
4551				dev_info(&udev->dev,
4552						"%s SuperSpeed%s USB device number %d using %s\n",
4553						(udev->config) ? "reset" : "new",
4554					 (udev->speed == USB_SPEED_SUPER_PLUS) ? "Plus" : "",
4555						devnum, udev->bus->controller->driver->name);
4556			}
4557
4558			/* cope with hardware quirkiness:
4559			 *  - let SET_ADDRESS settle, some device hardware wants it
4560			 *  - read ep0 maxpacket even for high and low speed,
4561			 */
4562			msleep(10);
4563			/* use_new_scheme() checks the speed which may have
4564			 * changed since the initial look so we cache the result
4565			 * in did_new_scheme
4566			 */
4567			if (did_new_scheme)
4568				break;
4569		}
4570
4571		retval = usb_get_device_descriptor(udev, 8);
4572		if (retval < 8) {
4573			if (retval != -ENODEV)
4574				dev_err(&udev->dev,
4575					"device descriptor read/8, error %d\n",
4576					retval);
4577			if (retval >= 0)
4578				retval = -EMSGSIZE;
4579		} else {
4580			retval = 0;
4581			break;
4582		}
4583	}
4584	if (retval)
4585		goto fail;
4586
4587	/*
4588	 * Some superspeed devices have finished the link training process
4589	 * and attached to a superspeed hub port, but the device descriptor
4590	 * got from those devices show they aren't superspeed devices. Warm
4591	 * reset the port attached by the devices can fix them.
4592	 */
4593	if ((udev->speed >= USB_SPEED_SUPER) &&
4594			(le16_to_cpu(udev->descriptor.bcdUSB) < 0x0300)) {
4595		dev_err(&udev->dev, "got a wrong device descriptor, "
4596				"warm reset device\n");
4597		hub_port_reset(hub, port1, udev,
4598				HUB_BH_RESET_TIME, true);
4599		retval = -EINVAL;
4600		goto fail;
4601	}
4602
4603	if (udev->descriptor.bMaxPacketSize0 == 0xff ||
4604			udev->speed >= USB_SPEED_SUPER)
4605		i = 512;
4606	else
4607		i = udev->descriptor.bMaxPacketSize0;
4608	if (usb_endpoint_maxp(&udev->ep0.desc) != i) {
4609		if (udev->speed == USB_SPEED_LOW ||
4610				!(i == 8 || i == 16 || i == 32 || i == 64)) {
4611			dev_err(&udev->dev, "Invalid ep0 maxpacket: %d\n", i);
4612			retval = -EMSGSIZE;
4613			goto fail;
4614		}
4615		if (udev->speed == USB_SPEED_FULL)
4616			dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
4617		else
4618			dev_warn(&udev->dev, "Using ep0 maxpacket: %d\n", i);
4619		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
4620		usb_ep0_reinit(udev);
4621	}
4622
4623	retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
4624	if (retval < (signed)sizeof(udev->descriptor)) {
4625		if (retval != -ENODEV)
4626			dev_err(&udev->dev, "device descriptor read/all, error %d\n",
4627					retval);
4628		if (retval >= 0)
4629			retval = -ENOMSG;
4630		goto fail;
4631	}
4632
4633	usb_detect_quirks(udev);
4634
4635	if (udev->wusb == 0 && le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0201) {
4636		retval = usb_get_bos_descriptor(udev);
4637		if (!retval) {
4638			udev->lpm_capable = usb_device_supports_lpm(udev);
4639			usb_set_lpm_parameters(udev);
4640		}
4641	}
4642
4643	retval = 0;
4644	/* notify HCD that we have a device connected and addressed */
4645	if (hcd->driver->update_device)
4646		hcd->driver->update_device(hcd, udev);
4647	hub_set_initial_usb2_lpm_policy(udev);
4648fail:
4649	if (retval) {
4650		hub_port_disable(hub, port1, 0);
4651		update_devnum(udev, devnum);	/* for disconnect processing */
4652	}
4653	mutex_unlock(&hdev->bus->usb_address0_mutex);
4654	return retval;
4655}
4656
4657static void
4658check_highspeed(struct usb_hub *hub, struct usb_device *udev, int port1)
4659{
4660	struct usb_qualifier_descriptor	*qual;
4661	int				status;
4662
4663	if (udev->quirks & USB_QUIRK_DEVICE_QUALIFIER)
4664		return;
4665
4666	qual = kmalloc(sizeof *qual, GFP_KERNEL);
4667	if (qual == NULL)
4668		return;
4669
4670	status = usb_get_descriptor(udev, USB_DT_DEVICE_QUALIFIER, 0,
4671			qual, sizeof *qual);
4672	if (status == sizeof *qual) {
4673		dev_info(&udev->dev, "not running at top speed; "
4674			"connect to a high speed hub\n");
4675		/* hub LEDs are probably harder to miss than syslog */
4676		if (hub->has_indicators) {
4677			hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
4678			queue_delayed_work(system_power_efficient_wq,
4679					&hub->leds, 0);
4680		}
4681	}
4682	kfree(qual);
4683}
4684
4685static unsigned
4686hub_power_remaining(struct usb_hub *hub)
4687{
4688	struct usb_device *hdev = hub->hdev;
4689	int remaining;
4690	int port1;
4691
4692	if (!hub->limited_power)
4693		return 0;
4694
4695	remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
4696	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
4697		struct usb_port *port_dev = hub->ports[port1 - 1];
4698		struct usb_device *udev = port_dev->child;
4699		unsigned unit_load;
4700		int delta;
4701
4702		if (!udev)
4703			continue;
4704		if (hub_is_superspeed(udev))
4705			unit_load = 150;
4706		else
4707			unit_load = 100;
4708
4709		/*
4710		 * Unconfigured devices may not use more than one unit load,
4711		 * or 8mA for OTG ports
4712		 */
4713		if (udev->actconfig)
4714			delta = usb_get_max_power(udev, udev->actconfig);
4715		else if (port1 != udev->bus->otg_port || hdev->parent)
4716			delta = unit_load;
4717		else
4718			delta = 8;
4719		if (delta > hub->mA_per_port)
4720			dev_warn(&port_dev->dev, "%dmA is over %umA budget!\n",
4721					delta, hub->mA_per_port);
4722		remaining -= delta;
4723	}
4724	if (remaining < 0) {
4725		dev_warn(hub->intfdev, "%dmA over power budget!\n",
4726			-remaining);
4727		remaining = 0;
4728	}
4729	return remaining;
4730}
4731
4732static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
4733		u16 portchange)
4734{
4735	int status, i;
4736	unsigned unit_load;
4737	struct usb_device *hdev = hub->hdev;
4738	struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
4739	struct usb_port *port_dev = hub->ports[port1 - 1];
4740	struct usb_device *udev = port_dev->child;
4741	static int unreliable_port = -1;
4742
4743	/* Disconnect any existing devices under this port */
4744	if (udev) {
4745		if (hcd->usb_phy && !hdev->parent)
4746			usb_phy_notify_disconnect(hcd->usb_phy, udev->speed);
4747		usb_disconnect(&port_dev->child);
4748	}
4749
4750	/* We can forget about a "removed" device when there's a physical
4751	 * disconnect or the connect status changes.
4752	 */
4753	if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
4754			(portchange & USB_PORT_STAT_C_CONNECTION))
4755		clear_bit(port1, hub->removed_bits);
4756
4757	if (portchange & (USB_PORT_STAT_C_CONNECTION |
4758				USB_PORT_STAT_C_ENABLE)) {
4759		status = hub_port_debounce_be_stable(hub, port1);
4760		if (status < 0) {
4761			if (status != -ENODEV &&
4762				port1 != unreliable_port &&
4763				printk_ratelimit())
4764				dev_err(&port_dev->dev, "connect-debounce failed\n");
4765			portstatus &= ~USB_PORT_STAT_CONNECTION;
4766			unreliable_port = port1;
4767		} else {
4768			portstatus = status;
4769		}
4770	}
4771
4772	/* Return now if debouncing failed or nothing is connected or
4773	 * the device was "removed".
4774	 */
4775	if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
4776			test_bit(port1, hub->removed_bits)) {
4777
4778		/*
4779		 * maybe switch power back on (e.g. root hub was reset)
4780		 * but only if the port isn't owned by someone else.
4781		 */
4782		if (hub_is_port_power_switchable(hub)
4783				&& !port_is_power_on(hub, portstatus)
4784				&& !port_dev->port_owner)
4785			set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
4786
4787		if (portstatus & USB_PORT_STAT_ENABLE)
4788			goto done;
4789		return;
4790	}
4791	if (hub_is_superspeed(hub->hdev))
4792		unit_load = 150;
4793	else
4794		unit_load = 100;
4795
4796	status = 0;
4797	for (i = 0; i < SET_CONFIG_TRIES; i++) {
4798
4799		/* reallocate for each attempt, since references
4800		 * to the previous one can escape in various ways
4801		 */
4802		udev = usb_alloc_dev(hdev, hdev->bus, port1);
4803		if (!udev) {
4804			dev_err(&port_dev->dev,
4805					"couldn't allocate usb_device\n");
4806			goto done;
4807		}
4808
4809		usb_set_device_state(udev, USB_STATE_POWERED);
4810		udev->bus_mA = hub->mA_per_port;
4811		udev->level = hdev->level + 1;
4812		udev->wusb = hub_is_wusb(hub);
4813
4814		/* Devices connected to SuperSpeed hubs are USB 3.0 or later */
4815		if (hub_is_superspeed(hub->hdev))
4816			udev->speed = USB_SPEED_SUPER;
4817		else
4818			udev->speed = USB_SPEED_UNKNOWN;
4819
4820		choose_devnum(udev);
4821		if (udev->devnum <= 0) {
4822			status = -ENOTCONN;	/* Don't retry */
4823			goto loop;
4824		}
4825
4826		/* reset (non-USB 3.0 devices) and get descriptor */
4827		usb_lock_port(port_dev);
4828		status = hub_port_init(hub, udev, port1, i);
4829		usb_unlock_port(port_dev);
4830		if (status < 0)
4831			goto loop;
4832
4833		if (udev->quirks & USB_QUIRK_DELAY_INIT)
4834			msleep(1000);
4835
4836		/* consecutive bus-powered hubs aren't reliable; they can
4837		 * violate the voltage drop budget.  if the new child has
4838		 * a "powered" LED, users should notice we didn't enable it
4839		 * (without reading syslog), even without per-port LEDs
4840		 * on the parent.
4841		 */
4842		if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
4843				&& udev->bus_mA <= unit_load) {
4844			u16	devstat;
4845
4846			status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
4847					&devstat);
4848			if (status) {
4849				dev_dbg(&udev->dev, "get status %d ?\n", status);
4850				goto loop_disable;
4851			}
4852			if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
4853				dev_err(&udev->dev,
4854					"can't connect bus-powered hub "
4855					"to this port\n");
4856				if (hub->has_indicators) {
4857					hub->indicator[port1-1] =
4858						INDICATOR_AMBER_BLINK;
4859					queue_delayed_work(
4860						system_power_efficient_wq,
4861						&hub->leds, 0);
4862				}
4863				status = -ENOTCONN;	/* Don't retry */
4864				goto loop_disable;
4865			}
4866		}
4867
4868		/* check for devices running slower than they could */
4869		if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
4870				&& udev->speed == USB_SPEED_FULL
4871				&& highspeed_hubs != 0)
4872			check_highspeed(hub, udev, port1);
4873
4874		/* Store the parent's children[] pointer.  At this point
4875		 * udev becomes globally accessible, although presumably
4876		 * no one will look at it until hdev is unlocked.
4877		 */
4878		status = 0;
4879
4880		mutex_lock(&usb_port_peer_mutex);
4881
4882		/* We mustn't add new devices if the parent hub has
4883		 * been disconnected; we would race with the
4884		 * recursively_mark_NOTATTACHED() routine.
4885		 */
4886		spin_lock_irq(&device_state_lock);
4887		if (hdev->state == USB_STATE_NOTATTACHED)
4888			status = -ENOTCONN;
4889		else
4890			port_dev->child = udev;
4891		spin_unlock_irq(&device_state_lock);
4892		mutex_unlock(&usb_port_peer_mutex);
4893
4894		/* Run it through the hoops (find a driver, etc) */
4895		if (!status) {
4896			status = usb_new_device(udev);
4897			if (status) {
4898				mutex_lock(&usb_port_peer_mutex);
4899				spin_lock_irq(&device_state_lock);
4900				port_dev->child = NULL;
4901				spin_unlock_irq(&device_state_lock);
4902				mutex_unlock(&usb_port_peer_mutex);
4903			} else {
4904				if (hcd->usb_phy && !hdev->parent)
4905					usb_phy_notify_connect(hcd->usb_phy,
4906							udev->speed);
4907			}
4908		}
4909
4910		if (status)
4911			goto loop_disable;
4912
4913		status = hub_power_remaining(hub);
4914		if (status)
4915			dev_dbg(hub->intfdev, "%dmA power budget left\n", status);
4916
4917		return;
4918
4919loop_disable:
4920		hub_port_disable(hub, port1, 1);
4921loop:
4922		usb_ep0_reinit(udev);
4923		release_devnum(udev);
4924		hub_free_dev(udev);
4925		usb_put_dev(udev);
4926		if ((status == -ENOTCONN) || (status == -ENOTSUPP))
4927			break;
4928	}
4929	if (hub->hdev->parent ||
4930			!hcd->driver->port_handed_over ||
4931			!(hcd->driver->port_handed_over)(hcd, port1)) {
4932		if (status != -ENOTCONN && status != -ENODEV)
4933			dev_err(&port_dev->dev,
4934					"unable to enumerate USB device\n");
4935	}
4936
4937done:
4938	hub_port_disable(hub, port1, 1);
4939	if (hcd->driver->relinquish_port && !hub->hdev->parent)
4940		hcd->driver->relinquish_port(hcd, port1);
4941
4942}
4943
4944/* Handle physical or logical connection change events.
4945 * This routine is called when:
4946 *	a port connection-change occurs;
4947 *	a port enable-change occurs (often caused by EMI);
4948 *	usb_reset_and_verify_device() encounters changed descriptors (as from
4949 *		a firmware download)
4950 * caller already locked the hub
4951 */
4952static void hub_port_connect_change(struct usb_hub *hub, int port1,
4953					u16 portstatus, u16 portchange)
4954		__must_hold(&port_dev->status_lock)
4955{
4956	struct usb_port *port_dev = hub->ports[port1 - 1];
4957	struct usb_device *udev = port_dev->child;
4958	int status = -ENODEV;
4959
4960	dev_dbg(&port_dev->dev, "status %04x, change %04x, %s\n", portstatus,
4961			portchange, portspeed(hub, portstatus));
4962
4963	if (hub->has_indicators) {
4964		set_port_led(hub, port1, HUB_LED_AUTO);
4965		hub->indicator[port1-1] = INDICATOR_AUTO;
4966	}
4967
4968#ifdef	CONFIG_USB_OTG
4969	/* during HNP, don't repeat the debounce */
4970	if (hub->hdev->bus->is_b_host)
4971		portchange &= ~(USB_PORT_STAT_C_CONNECTION |
4972				USB_PORT_STAT_C_ENABLE);
4973#endif
4974
4975	/* Try to resuscitate an existing device */
4976	if ((portstatus & USB_PORT_STAT_CONNECTION) && udev &&
4977			udev->state != USB_STATE_NOTATTACHED) {
4978		if (portstatus & USB_PORT_STAT_ENABLE) {
4979			status = 0;		/* Nothing to do */
4980#ifdef CONFIG_PM
4981		} else if (udev->state == USB_STATE_SUSPENDED &&
4982				udev->persist_enabled) {
4983			/* For a suspended device, treat this as a
4984			 * remote wakeup event.
4985			 */
4986			usb_unlock_port(port_dev);
4987			status = usb_remote_wakeup(udev);
4988			usb_lock_port(port_dev);
4989#endif
4990		} else {
4991			/* Don't resuscitate */;
4992		}
4993	}
4994	clear_bit(port1, hub->change_bits);
4995
4996	/* successfully revalidated the connection */
4997	if (status == 0)
4998		return;
4999
5000	usb_unlock_port(port_dev);
5001	hub_port_connect(hub, port1, portstatus, portchange);
5002	usb_lock_port(port_dev);
5003}
5004
5005static void port_event(struct usb_hub *hub, int port1)
5006		__must_hold(&port_dev->status_lock)
5007{
5008	int connect_change;
5009	struct usb_port *port_dev = hub->ports[port1 - 1];
5010	struct usb_device *udev = port_dev->child;
5011	struct usb_device *hdev = hub->hdev;
5012	u16 portstatus, portchange;
5013
5014	connect_change = test_bit(port1, hub->change_bits);
5015	clear_bit(port1, hub->event_bits);
5016	clear_bit(port1, hub->wakeup_bits);
5017
5018	if (hub_port_status(hub, port1, &portstatus, &portchange) < 0)
5019		return;
5020
5021	if (portchange & USB_PORT_STAT_C_CONNECTION) {
5022		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
5023		connect_change = 1;
5024	}
5025
5026	if (portchange & USB_PORT_STAT_C_ENABLE) {
5027		if (!connect_change)
5028			dev_dbg(&port_dev->dev, "enable change, status %08x\n",
5029					portstatus);
5030		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
5031
5032		/*
5033		 * EM interference sometimes causes badly shielded USB devices
5034		 * to be shutdown by the hub, this hack enables them again.
5035		 * Works at least with mouse driver.
5036		 */
5037		if (!(portstatus & USB_PORT_STAT_ENABLE)
5038		    && !connect_change && udev) {
5039			dev_err(&port_dev->dev, "disabled by hub (EMI?), re-enabling...\n");
5040			connect_change = 1;
5041		}
5042	}
5043
5044	if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
5045		u16 status = 0, unused;
5046
5047		dev_dbg(&port_dev->dev, "over-current change\n");
5048		usb_clear_port_feature(hdev, port1,
5049				USB_PORT_FEAT_C_OVER_CURRENT);
5050		msleep(100);	/* Cool down */
5051		hub_power_on(hub, true);
5052		hub_port_status(hub, port1, &status, &unused);
5053		if (status & USB_PORT_STAT_OVERCURRENT)
5054			dev_err(&port_dev->dev, "over-current condition\n");
5055	}
5056
5057	if (portchange & USB_PORT_STAT_C_RESET) {
5058		dev_dbg(&port_dev->dev, "reset change\n");
5059		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_RESET);
5060	}
5061	if ((portchange & USB_PORT_STAT_C_BH_RESET)
5062	    && hub_is_superspeed(hdev)) {
5063		dev_dbg(&port_dev->dev, "warm reset change\n");
5064		usb_clear_port_feature(hdev, port1,
5065				USB_PORT_FEAT_C_BH_PORT_RESET);
5066	}
5067	if (portchange & USB_PORT_STAT_C_LINK_STATE) {
5068		dev_dbg(&port_dev->dev, "link state change\n");
5069		usb_clear_port_feature(hdev, port1,
5070				USB_PORT_FEAT_C_PORT_LINK_STATE);
5071	}
5072	if (portchange & USB_PORT_STAT_C_CONFIG_ERROR) {
5073		dev_warn(&port_dev->dev, "config error\n");
5074		usb_clear_port_feature(hdev, port1,
5075				USB_PORT_FEAT_C_PORT_CONFIG_ERROR);
5076	}
5077
5078	/* skip port actions that require the port to be powered on */
5079	if (!pm_runtime_active(&port_dev->dev))
5080		return;
5081
5082	if (hub_handle_remote_wakeup(hub, port1, portstatus, portchange))
5083		connect_change = 1;
5084
5085	/*
5086	 * Warm reset a USB3 protocol port if it's in
5087	 * SS.Inactive state.
5088	 */
5089	if (hub_port_warm_reset_required(hub, port1, portstatus)) {
5090		dev_dbg(&port_dev->dev, "do warm reset\n");
5091		if (!udev || !(portstatus & USB_PORT_STAT_CONNECTION)
5092				|| udev->state == USB_STATE_NOTATTACHED) {
5093			if (hub_port_reset(hub, port1, NULL,
5094					HUB_BH_RESET_TIME, true) < 0)
5095				hub_port_disable(hub, port1, 1);
5096		} else {
5097			usb_unlock_port(port_dev);
5098			usb_lock_device(udev);
5099			usb_reset_device(udev);
5100			usb_unlock_device(udev);
5101			usb_lock_port(port_dev);
5102			connect_change = 0;
5103		}
5104	}
5105
5106	if (connect_change)
5107		hub_port_connect_change(hub, port1, portstatus, portchange);
5108}
5109
5110static void hub_event(struct work_struct *work)
5111{
5112	struct usb_device *hdev;
5113	struct usb_interface *intf;
5114	struct usb_hub *hub;
5115	struct device *hub_dev;
5116	u16 hubstatus;
5117	u16 hubchange;
5118	int i, ret;
5119
5120	hub = container_of(work, struct usb_hub, events);
5121	hdev = hub->hdev;
5122	hub_dev = hub->intfdev;
5123	intf = to_usb_interface(hub_dev);
5124
5125	dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
5126			hdev->state, hdev->maxchild,
5127			/* NOTE: expects max 15 ports... */
5128			(u16) hub->change_bits[0],
5129			(u16) hub->event_bits[0]);
5130
5131	/* Lock the device, then check to see if we were
5132	 * disconnected while waiting for the lock to succeed. */
5133	usb_lock_device(hdev);
5134	if (unlikely(hub->disconnected))
5135		goto out_hdev_lock;
5136
5137	/* If the hub has died, clean up after it */
5138	if (hdev->state == USB_STATE_NOTATTACHED) {
5139		hub->error = -ENODEV;
5140		hub_quiesce(hub, HUB_DISCONNECT);
5141		goto out_hdev_lock;
5142	}
5143
5144	/* Autoresume */
5145	ret = usb_autopm_get_interface(intf);
5146	if (ret) {
5147		dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
5148		goto out_hdev_lock;
5149	}
5150
5151	/* If this is an inactive hub, do nothing */
5152	if (hub->quiescing)
5153		goto out_autopm;
5154
5155	if (hub->error) {
5156		dev_dbg(hub_dev, "resetting for error %d\n", hub->error);
5157
5158		ret = usb_reset_device(hdev);
5159		if (ret) {
5160			dev_dbg(hub_dev, "error resetting hub: %d\n", ret);
5161			goto out_autopm;
5162		}
5163
5164		hub->nerrors = 0;
5165		hub->error = 0;
5166	}
5167
5168	/* deal with port status changes */
5169	for (i = 1; i <= hdev->maxchild; i++) {
5170		struct usb_port *port_dev = hub->ports[i - 1];
5171
5172		if (test_bit(i, hub->event_bits)
5173				|| test_bit(i, hub->change_bits)
5174				|| test_bit(i, hub->wakeup_bits)) {
5175			/*
5176			 * The get_noresume and barrier ensure that if
5177			 * the port was in the process of resuming, we
5178			 * flush that work and keep the port active for
5179			 * the duration of the port_event().  However,
5180			 * if the port is runtime pm suspended
5181			 * (powered-off), we leave it in that state, run
5182			 * an abbreviated port_event(), and move on.
5183			 */
5184			pm_runtime_get_noresume(&port_dev->dev);
5185			pm_runtime_barrier(&port_dev->dev);
5186			usb_lock_port(port_dev);
5187			port_event(hub, i);
5188			usb_unlock_port(port_dev);
5189			pm_runtime_put_sync(&port_dev->dev);
5190		}
5191	}
5192
5193	/* deal with hub status changes */
5194	if (test_and_clear_bit(0, hub->event_bits) == 0)
5195		;	/* do nothing */
5196	else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
5197		dev_err(hub_dev, "get_hub_status failed\n");
5198	else {
5199		if (hubchange & HUB_CHANGE_LOCAL_POWER) {
5200			dev_dbg(hub_dev, "power change\n");
5201			clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
5202			if (hubstatus & HUB_STATUS_LOCAL_POWER)
5203				/* FIXME: Is this always true? */
5204				hub->limited_power = 1;
5205			else
5206				hub->limited_power = 0;
5207		}
5208		if (hubchange & HUB_CHANGE_OVERCURRENT) {
5209			u16 status = 0;
5210			u16 unused;
5211
5212			dev_dbg(hub_dev, "over-current change\n");
5213			clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
5214			msleep(500);	/* Cool down */
5215			hub_power_on(hub, true);
5216			hub_hub_status(hub, &status, &unused);
5217			if (status & HUB_STATUS_OVERCURRENT)
5218				dev_err(hub_dev, "over-current condition\n");
5219		}
5220	}
5221
5222out_autopm:
5223	/* Balance the usb_autopm_get_interface() above */
5224	usb_autopm_put_interface_no_suspend(intf);
5225out_hdev_lock:
5226	usb_unlock_device(hdev);
5227
5228	/* Balance the stuff in kick_hub_wq() and allow autosuspend */
5229	usb_autopm_put_interface(intf);
5230	kref_put(&hub->kref, hub_release);
5231}
5232
5233static const struct usb_device_id hub_id_table[] = {
5234    { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5235			| USB_DEVICE_ID_MATCH_INT_CLASS,
5236      .idVendor = USB_VENDOR_GENESYS_LOGIC,
5237      .bInterfaceClass = USB_CLASS_HUB,
5238      .driver_info = HUB_QUIRK_CHECK_PORT_AUTOSUSPEND},
5239    { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
5240      .bDeviceClass = USB_CLASS_HUB},
5241    { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
5242      .bInterfaceClass = USB_CLASS_HUB},
5243    { }						/* Terminating entry */
5244};
5245
5246MODULE_DEVICE_TABLE(usb, hub_id_table);
5247
5248static struct usb_driver hub_driver = {
5249	.name =		"hub",
5250	.probe =	hub_probe,
5251	.disconnect =	hub_disconnect,
5252	.suspend =	hub_suspend,
5253	.resume =	hub_resume,
5254	.reset_resume =	hub_reset_resume,
5255	.pre_reset =	hub_pre_reset,
5256	.post_reset =	hub_post_reset,
5257	.unlocked_ioctl = hub_ioctl,
5258	.id_table =	hub_id_table,
5259	.supports_autosuspend =	1,
5260};
5261
5262int usb_hub_init(void)
5263{
5264	if (usb_register(&hub_driver) < 0) {
5265		printk(KERN_ERR "%s: can't register hub driver\n",
5266			usbcore_name);
5267		return -1;
5268	}
5269
5270	/*
5271	 * The workqueue needs to be freezable to avoid interfering with
5272	 * USB-PERSIST port handover. Otherwise it might see that a full-speed
5273	 * device was gone before the EHCI controller had handed its port
5274	 * over to the companion full-speed controller.
5275	 */
5276	hub_wq = alloc_workqueue("usb_hub_wq", WQ_FREEZABLE, 0);
5277	if (hub_wq)
5278		return 0;
5279
5280	/* Fall through if kernel_thread failed */
5281	usb_deregister(&hub_driver);
5282	pr_err("%s: can't allocate workqueue for usb hub\n", usbcore_name);
5283
5284	return -1;
5285}
5286
5287void usb_hub_cleanup(void)
5288{
5289	destroy_workqueue(hub_wq);
5290
5291	/*
5292	 * Hub resources are freed for us by usb_deregister. It calls
5293	 * usb_driver_purge on every device which in turn calls that
5294	 * devices disconnect function if it is using this driver.
5295	 * The hub_disconnect function takes care of releasing the
5296	 * individual hub resources. -greg
5297	 */
5298	usb_deregister(&hub_driver);
5299} /* usb_hub_cleanup() */
5300
5301static int descriptors_changed(struct usb_device *udev,
5302		struct usb_device_descriptor *old_device_descriptor,
5303		struct usb_host_bos *old_bos)
5304{
5305	int		changed = 0;
5306	unsigned	index;
5307	unsigned	serial_len = 0;
5308	unsigned	len;
5309	unsigned	old_length;
5310	int		length;
5311	char		*buf;
5312
5313	if (memcmp(&udev->descriptor, old_device_descriptor,
5314			sizeof(*old_device_descriptor)) != 0)
5315		return 1;
5316
5317	if ((old_bos && !udev->bos) || (!old_bos && udev->bos))
5318		return 1;
5319	if (udev->bos) {
5320		len = le16_to_cpu(udev->bos->desc->wTotalLength);
5321		if (len != le16_to_cpu(old_bos->desc->wTotalLength))
5322			return 1;
5323		if (memcmp(udev->bos->desc, old_bos->desc, len))
5324			return 1;
5325	}
5326
5327	/* Since the idVendor, idProduct, and bcdDevice values in the
5328	 * device descriptor haven't changed, we will assume the
5329	 * Manufacturer and Product strings haven't changed either.
5330	 * But the SerialNumber string could be different (e.g., a
5331	 * different flash card of the same brand).
5332	 */
5333	if (udev->serial)
5334		serial_len = strlen(udev->serial) + 1;
5335
5336	len = serial_len;
5337	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
5338		old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
5339		len = max(len, old_length);
5340	}
5341
5342	buf = kmalloc(len, GFP_NOIO);
5343	if (buf == NULL) {
5344		dev_err(&udev->dev, "no mem to re-read configs after reset\n");
5345		/* assume the worst */
5346		return 1;
5347	}
5348	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
5349		old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
5350		length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
5351				old_length);
5352		if (length != old_length) {
5353			dev_dbg(&udev->dev, "config index %d, error %d\n",
5354					index, length);
5355			changed = 1;
5356			break;
5357		}
5358		if (memcmp(buf, udev->rawdescriptors[index], old_length)
5359				!= 0) {
5360			dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
5361				index,
5362				((struct usb_config_descriptor *) buf)->
5363					bConfigurationValue);
5364			changed = 1;
5365			break;
5366		}
5367	}
5368
5369	if (!changed && serial_len) {
5370		length = usb_string(udev, udev->descriptor.iSerialNumber,
5371				buf, serial_len);
5372		if (length + 1 != serial_len) {
5373			dev_dbg(&udev->dev, "serial string error %d\n",
5374					length);
5375			changed = 1;
5376		} else if (memcmp(buf, udev->serial, length) != 0) {
5377			dev_dbg(&udev->dev, "serial string changed\n");
5378			changed = 1;
5379		}
5380	}
5381
5382	kfree(buf);
5383	return changed;
5384}
5385
5386/**
5387 * usb_reset_and_verify_device - perform a USB port reset to reinitialize a device
5388 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
5389 *
5390 * WARNING - don't use this routine to reset a composite device
5391 * (one with multiple interfaces owned by separate drivers)!
5392 * Use usb_reset_device() instead.
5393 *
5394 * Do a port reset, reassign the device's address, and establish its
5395 * former operating configuration.  If the reset fails, or the device's
5396 * descriptors change from their values before the reset, or the original
5397 * configuration and altsettings cannot be restored, a flag will be set
5398 * telling hub_wq to pretend the device has been disconnected and then
5399 * re-connected.  All drivers will be unbound, and the device will be
5400 * re-enumerated and probed all over again.
5401 *
5402 * Return: 0 if the reset succeeded, -ENODEV if the device has been
5403 * flagged for logical disconnection, or some other negative error code
5404 * if the reset wasn't even attempted.
5405 *
5406 * Note:
5407 * The caller must own the device lock and the port lock, the latter is
5408 * taken by usb_reset_device().  For example, it's safe to use
5409 * usb_reset_device() from a driver probe() routine after downloading
5410 * new firmware.  For calls that might not occur during probe(), drivers
5411 * should lock the device using usb_lock_device_for_reset().
5412 *
5413 * Locking exception: This routine may also be called from within an
5414 * autoresume handler.  Such usage won't conflict with other tasks
5415 * holding the device lock because these tasks should always call
5416 * usb_autopm_resume_device(), thereby preventing any unwanted
5417 * autoresume.  The autoresume handler is expected to have already
5418 * acquired the port lock before calling this routine.
5419 */
5420static int usb_reset_and_verify_device(struct usb_device *udev)
5421{
5422	struct usb_device		*parent_hdev = udev->parent;
5423	struct usb_hub			*parent_hub;
5424	struct usb_hcd			*hcd = bus_to_hcd(udev->bus);
5425	struct usb_device_descriptor	descriptor = udev->descriptor;
5426	struct usb_host_bos		*bos;
5427	int				i, j, ret = 0;
5428	int				port1 = udev->portnum;
5429
5430	if (udev->state == USB_STATE_NOTATTACHED ||
5431			udev->state == USB_STATE_SUSPENDED) {
5432		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
5433				udev->state);
5434		return -EINVAL;
5435	}
5436
5437	if (!parent_hdev)
5438		return -EISDIR;
5439
5440	parent_hub = usb_hub_to_struct_hub(parent_hdev);
5441
5442	/* Disable USB2 hardware LPM.
5443	 * It will be re-enabled by the enumeration process.
5444	 */
5445	if (udev->usb2_hw_lpm_enabled == 1)
5446		usb_set_usb2_hardware_lpm(udev, 0);
5447
5448	/* Disable LPM and LTM while we reset the device and reinstall the alt
5449	 * settings.  Device-initiated LPM settings, and system exit latency
5450	 * settings are cleared when the device is reset, so we have to set
5451	 * them up again.
5452	 */
5453	ret = usb_unlocked_disable_lpm(udev);
5454	if (ret) {
5455		dev_err(&udev->dev, "%s Failed to disable LPM\n.", __func__);
5456		goto re_enumerate_no_bos;
5457	}
5458	ret = usb_disable_ltm(udev);
5459	if (ret) {
5460		dev_err(&udev->dev, "%s Failed to disable LTM\n.",
5461				__func__);
5462		goto re_enumerate_no_bos;
5463	}
5464
5465	bos = udev->bos;
5466	udev->bos = NULL;
5467
5468	for (i = 0; i < SET_CONFIG_TRIES; ++i) {
5469
5470		/* ep0 maxpacket size may change; let the HCD know about it.
5471		 * Other endpoints will be handled by re-enumeration. */
5472		usb_ep0_reinit(udev);
5473		ret = hub_port_init(parent_hub, udev, port1, i);
5474		if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
5475			break;
5476	}
5477
5478	if (ret < 0)
5479		goto re_enumerate;
5480
5481	/* Device might have changed firmware (DFU or similar) */
5482	if (descriptors_changed(udev, &descriptor, bos)) {
5483		dev_info(&udev->dev, "device firmware changed\n");
5484		udev->descriptor = descriptor;	/* for disconnect() calls */
5485		goto re_enumerate;
5486	}
5487
5488	/* Restore the device's previous configuration */
5489	if (!udev->actconfig)
5490		goto done;
5491
5492	mutex_lock(hcd->bandwidth_mutex);
5493	ret = usb_hcd_alloc_bandwidth(udev, udev->actconfig, NULL, NULL);
5494	if (ret < 0) {
5495		dev_warn(&udev->dev,
5496				"Busted HC?  Not enough HCD resources for "
5497				"old configuration.\n");
5498		mutex_unlock(hcd->bandwidth_mutex);
5499		goto re_enumerate;
5500	}
5501	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
5502			USB_REQ_SET_CONFIGURATION, 0,
5503			udev->actconfig->desc.bConfigurationValue, 0,
5504			NULL, 0, USB_CTRL_SET_TIMEOUT);
5505	if (ret < 0) {
5506		dev_err(&udev->dev,
5507			"can't restore configuration #%d (error=%d)\n",
5508			udev->actconfig->desc.bConfigurationValue, ret);
5509		mutex_unlock(hcd->bandwidth_mutex);
5510		goto re_enumerate;
5511	}
5512	mutex_unlock(hcd->bandwidth_mutex);
5513	usb_set_device_state(udev, USB_STATE_CONFIGURED);
5514
5515	/* Put interfaces back into the same altsettings as before.
5516	 * Don't bother to send the Set-Interface request for interfaces
5517	 * that were already in altsetting 0; besides being unnecessary,
5518	 * many devices can't handle it.  Instead just reset the host-side
5519	 * endpoint state.
5520	 */
5521	for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
5522		struct usb_host_config *config = udev->actconfig;
5523		struct usb_interface *intf = config->interface[i];
5524		struct usb_interface_descriptor *desc;
5525
5526		desc = &intf->cur_altsetting->desc;
5527		if (desc->bAlternateSetting == 0) {
5528			usb_disable_interface(udev, intf, true);
5529			usb_enable_interface(udev, intf, true);
5530			ret = 0;
5531		} else {
5532			/* Let the bandwidth allocation function know that this
5533			 * device has been reset, and it will have to use
5534			 * alternate setting 0 as the current alternate setting.
5535			 */
5536			intf->resetting_device = 1;
5537			ret = usb_set_interface(udev, desc->bInterfaceNumber,
5538					desc->bAlternateSetting);
5539			intf->resetting_device = 0;
5540		}
5541		if (ret < 0) {
5542			dev_err(&udev->dev, "failed to restore interface %d "
5543				"altsetting %d (error=%d)\n",
5544				desc->bInterfaceNumber,
5545				desc->bAlternateSetting,
5546				ret);
5547			goto re_enumerate;
5548		}
5549		/* Resetting also frees any allocated streams */
5550		for (j = 0; j < intf->cur_altsetting->desc.bNumEndpoints; j++)
5551			intf->cur_altsetting->endpoint[j].streams = 0;
5552	}
5553
5554done:
5555	/* Now that the alt settings are re-installed, enable LTM and LPM. */
5556	usb_set_usb2_hardware_lpm(udev, 1);
5557	usb_unlocked_enable_lpm(udev);
5558	usb_enable_ltm(udev);
5559	usb_release_bos_descriptor(udev);
5560	udev->bos = bos;
5561	return 0;
5562
5563re_enumerate:
5564	usb_release_bos_descriptor(udev);
5565	udev->bos = bos;
5566re_enumerate_no_bos:
5567	/* LPM state doesn't matter when we're about to destroy the device. */
5568	hub_port_logical_disconnect(parent_hub, port1);
5569	return -ENODEV;
5570}
5571
5572/**
5573 * usb_reset_device - warn interface drivers and perform a USB port reset
5574 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
5575 *
5576 * Warns all drivers bound to registered interfaces (using their pre_reset
5577 * method), performs the port reset, and then lets the drivers know that
5578 * the reset is over (using their post_reset method).
5579 *
5580 * Return: The same as for usb_reset_and_verify_device().
5581 *
5582 * Note:
5583 * The caller must own the device lock.  For example, it's safe to use
5584 * this from a driver probe() routine after downloading new firmware.
5585 * For calls that might not occur during probe(), drivers should lock
5586 * the device using usb_lock_device_for_reset().
5587 *
5588 * If an interface is currently being probed or disconnected, we assume
5589 * its driver knows how to handle resets.  For all other interfaces,
5590 * if the driver doesn't have pre_reset and post_reset methods then
5591 * we attempt to unbind it and rebind afterward.
5592 */
5593int usb_reset_device(struct usb_device *udev)
5594{
5595	int ret;
5596	int i;
5597	unsigned int noio_flag;
5598	struct usb_port *port_dev;
5599	struct usb_host_config *config = udev->actconfig;
5600	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
5601
5602	if (udev->state == USB_STATE_NOTATTACHED ||
5603			udev->state == USB_STATE_SUSPENDED) {
5604		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
5605				udev->state);
5606		return -EINVAL;
5607	}
5608
5609	if (!udev->parent) {
5610		/* this requires hcd-specific logic; see ohci_restart() */
5611		dev_dbg(&udev->dev, "%s for root hub!\n", __func__);
5612		return -EISDIR;
5613	}
5614
5615	port_dev = hub->ports[udev->portnum - 1];
5616
5617	/*
5618	 * Don't allocate memory with GFP_KERNEL in current
5619	 * context to avoid possible deadlock if usb mass
5620	 * storage interface or usbnet interface(iSCSI case)
5621	 * is included in current configuration. The easist
5622	 * approach is to do it for every device reset,
5623	 * because the device 'memalloc_noio' flag may have
5624	 * not been set before reseting the usb device.
5625	 */
5626	noio_flag = memalloc_noio_save();
5627
5628	/* Prevent autosuspend during the reset */
5629	usb_autoresume_device(udev);
5630
5631	if (config) {
5632		for (i = 0; i < config->desc.bNumInterfaces; ++i) {
5633			struct usb_interface *cintf = config->interface[i];
5634			struct usb_driver *drv;
5635			int unbind = 0;
5636
5637			if (cintf->dev.driver) {
5638				drv = to_usb_driver(cintf->dev.driver);
5639				if (drv->pre_reset && drv->post_reset)
5640					unbind = (drv->pre_reset)(cintf);
5641				else if (cintf->condition ==
5642						USB_INTERFACE_BOUND)
5643					unbind = 1;
5644				if (unbind)
5645					usb_forced_unbind_intf(cintf);
5646			}
5647		}
5648	}
5649
5650	usb_lock_port(port_dev);
5651	ret = usb_reset_and_verify_device(udev);
5652	usb_unlock_port(port_dev);
5653
5654	if (config) {
5655		for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
5656			struct usb_interface *cintf = config->interface[i];
5657			struct usb_driver *drv;
5658			int rebind = cintf->needs_binding;
5659
5660			if (!rebind && cintf->dev.driver) {
5661				drv = to_usb_driver(cintf->dev.driver);
5662				if (drv->post_reset)
5663					rebind = (drv->post_reset)(cintf);
5664				else if (cintf->condition ==
5665						USB_INTERFACE_BOUND)
5666					rebind = 1;
5667				if (rebind)
5668					cintf->needs_binding = 1;
5669			}
5670		}
5671		usb_unbind_and_rebind_marked_interfaces(udev);
5672	}
5673
5674	usb_autosuspend_device(udev);
5675	memalloc_noio_restore(noio_flag);
5676	return ret;
5677}
5678EXPORT_SYMBOL_GPL(usb_reset_device);
5679
5680
5681/**
5682 * usb_queue_reset_device - Reset a USB device from an atomic context
5683 * @iface: USB interface belonging to the device to reset
5684 *
5685 * This function can be used to reset a USB device from an atomic
5686 * context, where usb_reset_device() won't work (as it blocks).
5687 *
5688 * Doing a reset via this method is functionally equivalent to calling
5689 * usb_reset_device(), except for the fact that it is delayed to a
5690 * workqueue. This means that any drivers bound to other interfaces
5691 * might be unbound, as well as users from usbfs in user space.
5692 *
5693 * Corner cases:
5694 *
5695 * - Scheduling two resets at the same time from two different drivers
5696 *   attached to two different interfaces of the same device is
5697 *   possible; depending on how the driver attached to each interface
5698 *   handles ->pre_reset(), the second reset might happen or not.
5699 *
5700 * - If the reset is delayed so long that the interface is unbound from
5701 *   its driver, the reset will be skipped.
5702 *
5703 * - This function can be called during .probe().  It can also be called
5704 *   during .disconnect(), but doing so is pointless because the reset
5705 *   will not occur.  If you really want to reset the device during
5706 *   .disconnect(), call usb_reset_device() directly -- but watch out
5707 *   for nested unbinding issues!
5708 */
5709void usb_queue_reset_device(struct usb_interface *iface)
5710{
5711	if (schedule_work(&iface->reset_ws))
5712		usb_get_intf(iface);
5713}
5714EXPORT_SYMBOL_GPL(usb_queue_reset_device);
5715
5716/**
5717 * usb_hub_find_child - Get the pointer of child device
5718 * attached to the port which is specified by @port1.
5719 * @hdev: USB device belonging to the usb hub
5720 * @port1: port num to indicate which port the child device
5721 *	is attached to.
5722 *
5723 * USB drivers call this function to get hub's child device
5724 * pointer.
5725 *
5726 * Return: %NULL if input param is invalid and
5727 * child's usb_device pointer if non-NULL.
5728 */
5729struct usb_device *usb_hub_find_child(struct usb_device *hdev,
5730		int port1)
5731{
5732	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
5733
5734	if (port1 < 1 || port1 > hdev->maxchild)
5735		return NULL;
5736	return hub->ports[port1 - 1]->child;
5737}
5738EXPORT_SYMBOL_GPL(usb_hub_find_child);
5739
5740void usb_hub_adjust_deviceremovable(struct usb_device *hdev,
5741		struct usb_hub_descriptor *desc)
5742{
5743	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
5744	enum usb_port_connect_type connect_type;
5745	int i;
5746
5747	if (!hub)
5748		return;
5749
5750	if (!hub_is_superspeed(hdev)) {
5751		for (i = 1; i <= hdev->maxchild; i++) {
5752			struct usb_port *port_dev = hub->ports[i - 1];
5753
5754			connect_type = port_dev->connect_type;
5755			if (connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
5756				u8 mask = 1 << (i%8);
5757
5758				if (!(desc->u.hs.DeviceRemovable[i/8] & mask)) {
5759					dev_dbg(&port_dev->dev, "DeviceRemovable is changed to 1 according to platform information.\n");
5760					desc->u.hs.DeviceRemovable[i/8]	|= mask;
5761				}
5762			}
5763		}
5764	} else {
5765		u16 port_removable = le16_to_cpu(desc->u.ss.DeviceRemovable);
5766
5767		for (i = 1; i <= hdev->maxchild; i++) {
5768			struct usb_port *port_dev = hub->ports[i - 1];
5769
5770			connect_type = port_dev->connect_type;
5771			if (connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
5772				u16 mask = 1 << i;
5773
5774				if (!(port_removable & mask)) {
5775					dev_dbg(&port_dev->dev, "DeviceRemovable is changed to 1 according to platform information.\n");
5776					port_removable |= mask;
5777				}
5778			}
5779		}
5780
5781		desc->u.ss.DeviceRemovable = cpu_to_le16(port_removable);
5782	}
5783}
5784
5785#ifdef CONFIG_ACPI
5786/**
5787 * usb_get_hub_port_acpi_handle - Get the usb port's acpi handle
5788 * @hdev: USB device belonging to the usb hub
5789 * @port1: port num of the port
5790 *
5791 * Return: Port's acpi handle if successful, %NULL if params are
5792 * invalid.
5793 */
5794acpi_handle usb_get_hub_port_acpi_handle(struct usb_device *hdev,
5795	int port1)
5796{
5797	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
5798
5799	if (!hub)
5800		return NULL;
5801
5802	return ACPI_HANDLE(&hub->ports[port1 - 1]->dev);
5803}
5804#endif