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/drivers/usb/core/hub.c

https://bitbucket.org/cyanogenmod/android_kernel_asus_tf300t
C | 4051 lines | 2699 code | 486 blank | 866 comment | 636 complexity | 391473d5e0cab8c688aa1a8fac051e4a MD5 | raw file
Possible License(s): LGPL-2.0, AGPL-1.0, GPL-2.0

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   1/*
   2 * USB hub driver.
   3 *
   4 * (C) Copyright 1999 Linus Torvalds
   5 * (C) Copyright 1999 Johannes Erdfelt
   6 * (C) Copyright 1999 Gregory P. Smith
   7 * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
   8 *
   9 */
  10
  11#include <linux/kernel.h>
  12#include <linux/errno.h>
  13#include <linux/module.h>
  14#include <linux/moduleparam.h>
  15#include <linux/completion.h>
  16#include <linux/sched.h>
  17#include <linux/list.h>
  18#include <linux/slab.h>
  19#include <linux/ioctl.h>
  20#include <linux/usb.h>
  21#include <linux/usbdevice_fs.h>
  22#include <linux/usb/hcd.h>
  23#include <linux/usb/quirks.h>
  24#include <linux/kthread.h>
  25#include <linux/mutex.h>
  26#include <linux/freezer.h>
  27
  28#include <asm/uaccess.h>
  29#include <asm/byteorder.h>
  30
  31#include "usb.h"
  32
  33/* if we are in debug mode, always announce new devices */
  34#ifdef DEBUG
  35#ifndef CONFIG_USB_ANNOUNCE_NEW_DEVICES
  36#define CONFIG_USB_ANNOUNCE_NEW_DEVICES
  37#endif
  38#endif
  39
  40struct usb_hub {
  41	struct device		*intfdev;	/* the "interface" device */
  42	struct usb_device	*hdev;
  43	struct kref		kref;
  44	struct urb		*urb;		/* for interrupt polling pipe */
  45
  46	/* buffer for urb ... with extra space in case of babble */
  47	char			(*buffer)[8];
  48	union {
  49		struct usb_hub_status	hub;
  50		struct usb_port_status	port;
  51	}			*status;	/* buffer for status reports */
  52	struct mutex		status_mutex;	/* for the status buffer */
  53
  54	int			error;		/* last reported error */
  55	int			nerrors;	/* track consecutive errors */
  56
  57	struct list_head	event_list;	/* hubs w/data or errs ready */
  58	unsigned long		event_bits[1];	/* status change bitmask */
  59	unsigned long		change_bits[1];	/* ports with logical connect
  60							status change */
  61	unsigned long		busy_bits[1];	/* ports being reset or
  62							resumed */
  63	unsigned long		removed_bits[1]; /* ports with a "removed"
  64							device present */
  65#if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
  66#error event_bits[] is too short!
  67#endif
  68
  69	struct usb_hub_descriptor *descriptor;	/* class descriptor */
  70	struct usb_tt		tt;		/* Transaction Translator */
  71
  72	unsigned		mA_per_port;	/* current for each child */
  73
  74	unsigned		limited_power:1;
  75	unsigned		quiescing:1;
  76	unsigned		disconnected:1;
  77
  78	unsigned		has_indicators:1;
  79	u8			indicator[USB_MAXCHILDREN];
  80	struct delayed_work	leds;
  81	struct delayed_work	init_work;
  82	void			**port_owners;
  83};
  84
  85static inline int hub_is_superspeed(struct usb_device *hdev)
  86{
  87	return (hdev->descriptor.bDeviceProtocol == 3);
  88}
  89
  90/* Protect struct usb_device->state and ->children members
  91 * Note: Both are also protected by ->dev.sem, except that ->state can
  92 * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
  93static DEFINE_SPINLOCK(device_state_lock);
  94
  95/* khubd's worklist and its lock */
  96static DEFINE_SPINLOCK(hub_event_lock);
  97static LIST_HEAD(hub_event_list);	/* List of hubs needing servicing */
  98
  99/* Wakes up khubd */
 100static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
 101
 102static struct task_struct *khubd_task;
 103
 104/* cycle leds on hubs that aren't blinking for attention */
 105static int blinkenlights = 0;
 106module_param (blinkenlights, bool, S_IRUGO);
 107MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
 108
 109/*
 110 * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
 111 * 10 seconds to send reply for the initial 64-byte descriptor request.
 112 */
 113/* define initial 64-byte descriptor request timeout in milliseconds */
 114static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
 115module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
 116MODULE_PARM_DESC(initial_descriptor_timeout,
 117		"initial 64-byte descriptor request timeout in milliseconds "
 118		"(default 5000 - 5.0 seconds)");
 119
 120/*
 121 * As of 2.6.10 we introduce a new USB device initialization scheme which
 122 * closely resembles the way Windows works.  Hopefully it will be compatible
 123 * with a wider range of devices than the old scheme.  However some previously
 124 * working devices may start giving rise to "device not accepting address"
 125 * errors; if that happens the user can try the old scheme by adjusting the
 126 * following module parameters.
 127 *
 128 * For maximum flexibility there are two boolean parameters to control the
 129 * hub driver's behavior.  On the first initialization attempt, if the
 130 * "old_scheme_first" parameter is set then the old scheme will be used,
 131 * otherwise the new scheme is used.  If that fails and "use_both_schemes"
 132 * is set, then the driver will make another attempt, using the other scheme.
 133 */
 134static int old_scheme_first = 0;
 135module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
 136MODULE_PARM_DESC(old_scheme_first,
 137		 "start with the old device initialization scheme");
 138
 139static int use_both_schemes = 1;
 140module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
 141MODULE_PARM_DESC(use_both_schemes,
 142		"try the other device initialization scheme if the "
 143		"first one fails");
 144
 145/* Mutual exclusion for EHCI CF initialization.  This interferes with
 146 * port reset on some companion controllers.
 147 */
 148DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
 149EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
 150
 151#define HUB_DEBOUNCE_TIMEOUT	1500
 152#define HUB_DEBOUNCE_STEP	  25
 153#define HUB_DEBOUNCE_STABLE	 100
 154
 155
 156static int usb_reset_and_verify_device(struct usb_device *udev);
 157
 158static inline char *portspeed(struct usb_hub *hub, int portstatus)
 159{
 160	if (hub_is_superspeed(hub->hdev))
 161		return "5.0 Gb/s";
 162	if (portstatus & USB_PORT_STAT_HIGH_SPEED)
 163    		return "480 Mb/s";
 164	else if (portstatus & USB_PORT_STAT_LOW_SPEED)
 165		return "1.5 Mb/s";
 166	else
 167		return "12 Mb/s";
 168}
 169
 170/* Note that hdev or one of its children must be locked! */
 171static struct usb_hub *hdev_to_hub(struct usb_device *hdev)
 172{
 173	if (!hdev || !hdev->actconfig)
 174		return NULL;
 175	return usb_get_intfdata(hdev->actconfig->interface[0]);
 176}
 177
 178/* USB 2.0 spec Section 11.24.4.5 */
 179static int get_hub_descriptor(struct usb_device *hdev, void *data)
 180{
 181	int i, ret, size;
 182	unsigned dtype;
 183
 184	if (hub_is_superspeed(hdev)) {
 185		dtype = USB_DT_SS_HUB;
 186		size = USB_DT_SS_HUB_SIZE;
 187	} else {
 188		dtype = USB_DT_HUB;
 189		size = sizeof(struct usb_hub_descriptor);
 190	}
 191
 192	for (i = 0; i < 3; i++) {
 193		ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 194			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
 195			dtype << 8, 0, data, size,
 196			USB_CTRL_GET_TIMEOUT);
 197		if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
 198			return ret;
 199	}
 200	return -EINVAL;
 201}
 202
 203/*
 204 * USB 2.0 spec Section 11.24.2.1
 205 */
 206static int clear_hub_feature(struct usb_device *hdev, int feature)
 207{
 208	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 209		USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
 210}
 211
 212/*
 213 * USB 2.0 spec Section 11.24.2.2
 214 */
 215static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
 216{
 217	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 218		USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
 219		NULL, 0, 1000);
 220}
 221
 222/*
 223 * USB 2.0 spec Section 11.24.2.13
 224 */
 225static int set_port_feature(struct usb_device *hdev, int port1, int feature)
 226{
 227	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 228		USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
 229		NULL, 0, 1000);
 230}
 231
 232/*
 233 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
 234 * for info about using port indicators
 235 */
 236static void set_port_led(
 237	struct usb_hub *hub,
 238	int port1,
 239	int selector
 240)
 241{
 242	int status = set_port_feature(hub->hdev, (selector << 8) | port1,
 243			USB_PORT_FEAT_INDICATOR);
 244	if (status < 0)
 245		dev_dbg (hub->intfdev,
 246			"port %d indicator %s status %d\n",
 247			port1,
 248			({ char *s; switch (selector) {
 249			case HUB_LED_AMBER: s = "amber"; break;
 250			case HUB_LED_GREEN: s = "green"; break;
 251			case HUB_LED_OFF: s = "off"; break;
 252			case HUB_LED_AUTO: s = "auto"; break;
 253			default: s = "??"; break;
 254			}; s; }),
 255			status);
 256}
 257
 258#define	LED_CYCLE_PERIOD	((2*HZ)/3)
 259
 260static void led_work (struct work_struct *work)
 261{
 262	struct usb_hub		*hub =
 263		container_of(work, struct usb_hub, leds.work);
 264	struct usb_device	*hdev = hub->hdev;
 265	unsigned		i;
 266	unsigned		changed = 0;
 267	int			cursor = -1;
 268
 269	if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
 270		return;
 271
 272	for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
 273		unsigned	selector, mode;
 274
 275		/* 30%-50% duty cycle */
 276
 277		switch (hub->indicator[i]) {
 278		/* cycle marker */
 279		case INDICATOR_CYCLE:
 280			cursor = i;
 281			selector = HUB_LED_AUTO;
 282			mode = INDICATOR_AUTO;
 283			break;
 284		/* blinking green = sw attention */
 285		case INDICATOR_GREEN_BLINK:
 286			selector = HUB_LED_GREEN;
 287			mode = INDICATOR_GREEN_BLINK_OFF;
 288			break;
 289		case INDICATOR_GREEN_BLINK_OFF:
 290			selector = HUB_LED_OFF;
 291			mode = INDICATOR_GREEN_BLINK;
 292			break;
 293		/* blinking amber = hw attention */
 294		case INDICATOR_AMBER_BLINK:
 295			selector = HUB_LED_AMBER;
 296			mode = INDICATOR_AMBER_BLINK_OFF;
 297			break;
 298		case INDICATOR_AMBER_BLINK_OFF:
 299			selector = HUB_LED_OFF;
 300			mode = INDICATOR_AMBER_BLINK;
 301			break;
 302		/* blink green/amber = reserved */
 303		case INDICATOR_ALT_BLINK:
 304			selector = HUB_LED_GREEN;
 305			mode = INDICATOR_ALT_BLINK_OFF;
 306			break;
 307		case INDICATOR_ALT_BLINK_OFF:
 308			selector = HUB_LED_AMBER;
 309			mode = INDICATOR_ALT_BLINK;
 310			break;
 311		default:
 312			continue;
 313		}
 314		if (selector != HUB_LED_AUTO)
 315			changed = 1;
 316		set_port_led(hub, i + 1, selector);
 317		hub->indicator[i] = mode;
 318	}
 319	if (!changed && blinkenlights) {
 320		cursor++;
 321		cursor %= hub->descriptor->bNbrPorts;
 322		set_port_led(hub, cursor + 1, HUB_LED_GREEN);
 323		hub->indicator[cursor] = INDICATOR_CYCLE;
 324		changed++;
 325	}
 326	if (changed)
 327		schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 328}
 329
 330/* use a short timeout for hub/port status fetches */
 331#define	USB_STS_TIMEOUT		1000
 332#define	USB_STS_RETRIES		5
 333
 334/*
 335 * USB 2.0 spec Section 11.24.2.6
 336 */
 337static int get_hub_status(struct usb_device *hdev,
 338		struct usb_hub_status *data)
 339{
 340	int i, status = -ETIMEDOUT;
 341
 342	for (i = 0; i < USB_STS_RETRIES &&
 343			(status == -ETIMEDOUT || status == -EPIPE); i++) {
 344		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 345			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
 346			data, sizeof(*data), USB_STS_TIMEOUT);
 347	}
 348	return status;
 349}
 350
 351/*
 352 * USB 2.0 spec Section 11.24.2.7
 353 */
 354static int get_port_status(struct usb_device *hdev, int port1,
 355		struct usb_port_status *data)
 356{
 357	int i, status = -ETIMEDOUT;
 358
 359	for (i = 0; i < USB_STS_RETRIES &&
 360			(status == -ETIMEDOUT || status == -EPIPE); i++) {
 361		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 362			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
 363			data, sizeof(*data), USB_STS_TIMEOUT);
 364	}
 365	return status;
 366}
 367
 368static int hub_port_status(struct usb_hub *hub, int port1,
 369		u16 *status, u16 *change)
 370{
 371	int ret;
 372
 373	mutex_lock(&hub->status_mutex);
 374	ret = get_port_status(hub->hdev, port1, &hub->status->port);
 375	if (ret < 4) {
 376		dev_err(hub->intfdev,
 377			"%s failed (err = %d)\n", __func__, ret);
 378		if (ret >= 0)
 379			ret = -EIO;
 380	} else {
 381		*status = le16_to_cpu(hub->status->port.wPortStatus);
 382		*change = le16_to_cpu(hub->status->port.wPortChange);
 383
 384		ret = 0;
 385	}
 386	mutex_unlock(&hub->status_mutex);
 387	return ret;
 388}
 389
 390static void kick_khubd(struct usb_hub *hub)
 391{
 392	unsigned long	flags;
 393
 394	spin_lock_irqsave(&hub_event_lock, flags);
 395	if (!hub->disconnected && list_empty(&hub->event_list)) {
 396		list_add_tail(&hub->event_list, &hub_event_list);
 397
 398		/* Suppress autosuspend until khubd runs */
 399		usb_autopm_get_interface_no_resume(
 400				to_usb_interface(hub->intfdev));
 401		wake_up(&khubd_wait);
 402	}
 403	spin_unlock_irqrestore(&hub_event_lock, flags);
 404}
 405
 406void usb_kick_khubd(struct usb_device *hdev)
 407{
 408	struct usb_hub *hub = hdev_to_hub(hdev);
 409
 410	if (hub)
 411		kick_khubd(hub);
 412}
 413
 414
 415/* completion function, fires on port status changes and various faults */
 416static void hub_irq(struct urb *urb)
 417{
 418	struct usb_hub *hub = urb->context;
 419	int status = urb->status;
 420	unsigned i;
 421	unsigned long bits;
 422
 423	switch (status) {
 424	case -ENOENT:		/* synchronous unlink */
 425	case -ECONNRESET:	/* async unlink */
 426	case -ESHUTDOWN:	/* hardware going away */
 427		return;
 428
 429	default:		/* presumably an error */
 430		/* Cause a hub reset after 10 consecutive errors */
 431		dev_dbg (hub->intfdev, "transfer --> %d\n", status);
 432		if ((++hub->nerrors < 10) || hub->error)
 433			goto resubmit;
 434		hub->error = status;
 435		/* FALL THROUGH */
 436
 437	/* let khubd handle things */
 438	case 0:			/* we got data:  port status changed */
 439		bits = 0;
 440		for (i = 0; i < urb->actual_length; ++i)
 441			bits |= ((unsigned long) ((*hub->buffer)[i]))
 442					<< (i*8);
 443		hub->event_bits[0] = bits;
 444		break;
 445	}
 446
 447	hub->nerrors = 0;
 448
 449	/* Something happened, let khubd figure it out */
 450	kick_khubd(hub);
 451
 452resubmit:
 453	if (hub->quiescing)
 454		return;
 455
 456	if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
 457			&& status != -ENODEV && status != -EPERM)
 458		dev_err (hub->intfdev, "resubmit --> %d\n", status);
 459}
 460
 461/* USB 2.0 spec Section 11.24.2.3 */
 462static inline int
 463hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
 464{
 465	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 466			       HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
 467			       tt, NULL, 0, 1000);
 468}
 469
 470/*
 471 * enumeration blocks khubd for a long time. we use keventd instead, since
 472 * long blocking there is the exception, not the rule.  accordingly, HCDs
 473 * talking to TTs must queue control transfers (not just bulk and iso), so
 474 * both can talk to the same hub concurrently.
 475 */
 476static void hub_tt_work(struct work_struct *work)
 477{
 478	struct usb_hub		*hub =
 479		container_of(work, struct usb_hub, tt.clear_work);
 480	unsigned long		flags;
 481	int			limit = 100;
 482
 483	spin_lock_irqsave (&hub->tt.lock, flags);
 484	while (--limit && !list_empty (&hub->tt.clear_list)) {
 485		struct list_head	*next;
 486		struct usb_tt_clear	*clear;
 487		struct usb_device	*hdev = hub->hdev;
 488		const struct hc_driver	*drv;
 489		int			status;
 490
 491		next = hub->tt.clear_list.next;
 492		clear = list_entry (next, struct usb_tt_clear, clear_list);
 493		list_del (&clear->clear_list);
 494
 495		/* drop lock so HCD can concurrently report other TT errors */
 496		spin_unlock_irqrestore (&hub->tt.lock, flags);
 497		status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
 498		if (status)
 499			dev_err (&hdev->dev,
 500				"clear tt %d (%04x) error %d\n",
 501				clear->tt, clear->devinfo, status);
 502
 503		/* Tell the HCD, even if the operation failed */
 504		drv = clear->hcd->driver;
 505		if (drv->clear_tt_buffer_complete)
 506			(drv->clear_tt_buffer_complete)(clear->hcd, clear->ep);
 507
 508		kfree(clear);
 509		spin_lock_irqsave(&hub->tt.lock, flags);
 510	}
 511	spin_unlock_irqrestore (&hub->tt.lock, flags);
 512}
 513
 514/**
 515 * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
 516 * @urb: an URB associated with the failed or incomplete split transaction
 517 *
 518 * High speed HCDs use this to tell the hub driver that some split control or
 519 * bulk transaction failed in a way that requires clearing internal state of
 520 * a transaction translator.  This is normally detected (and reported) from
 521 * interrupt context.
 522 *
 523 * It may not be possible for that hub to handle additional full (or low)
 524 * speed transactions until that state is fully cleared out.
 525 */
 526int usb_hub_clear_tt_buffer(struct urb *urb)
 527{
 528	struct usb_device	*udev = urb->dev;
 529	int			pipe = urb->pipe;
 530	struct usb_tt		*tt = udev->tt;
 531	unsigned long		flags;
 532	struct usb_tt_clear	*clear;
 533
 534	/* we've got to cope with an arbitrary number of pending TT clears,
 535	 * since each TT has "at least two" buffers that can need it (and
 536	 * there can be many TTs per hub).  even if they're uncommon.
 537	 */
 538	if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) {
 539		dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
 540		/* FIXME recover somehow ... RESET_TT? */
 541		return -ENOMEM;
 542	}
 543
 544	/* info that CLEAR_TT_BUFFER needs */
 545	clear->tt = tt->multi ? udev->ttport : 1;
 546	clear->devinfo = usb_pipeendpoint (pipe);
 547	clear->devinfo |= udev->devnum << 4;
 548	clear->devinfo |= usb_pipecontrol (pipe)
 549			? (USB_ENDPOINT_XFER_CONTROL << 11)
 550			: (USB_ENDPOINT_XFER_BULK << 11);
 551	if (usb_pipein (pipe))
 552		clear->devinfo |= 1 << 15;
 553
 554	/* info for completion callback */
 555	clear->hcd = bus_to_hcd(udev->bus);
 556	clear->ep = urb->ep;
 557
 558	/* tell keventd to clear state for this TT */
 559	spin_lock_irqsave (&tt->lock, flags);
 560	list_add_tail (&clear->clear_list, &tt->clear_list);
 561	schedule_work(&tt->clear_work);
 562	spin_unlock_irqrestore (&tt->lock, flags);
 563	return 0;
 564}
 565EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer);
 566
 567/* If do_delay is false, return the number of milliseconds the caller
 568 * needs to delay.
 569 */
 570static unsigned hub_power_on(struct usb_hub *hub, bool do_delay)
 571{
 572	int port1;
 573	unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
 574	unsigned delay;
 575	u16 wHubCharacteristics =
 576			le16_to_cpu(hub->descriptor->wHubCharacteristics);
 577
 578	/* Enable power on each port.  Some hubs have reserved values
 579	 * of LPSM (> 2) in their descriptors, even though they are
 580	 * USB 2.0 hubs.  Some hubs do not implement port-power switching
 581	 * but only emulate it.  In all cases, the ports won't work
 582	 * unless we send these messages to the hub.
 583	 */
 584	if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
 585		dev_dbg(hub->intfdev, "enabling power on all ports\n");
 586	else
 587		dev_dbg(hub->intfdev, "trying to enable port power on "
 588				"non-switchable hub\n");
 589	for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
 590		set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
 591
 592	/* Wait at least 100 msec for power to become stable */
 593	delay = max(pgood_delay, (unsigned) 100);
 594	if (do_delay)
 595		msleep(delay);
 596	return delay;
 597}
 598
 599static int hub_hub_status(struct usb_hub *hub,
 600		u16 *status, u16 *change)
 601{
 602	int ret;
 603
 604	mutex_lock(&hub->status_mutex);
 605	ret = get_hub_status(hub->hdev, &hub->status->hub);
 606	if (ret < 0)
 607		dev_err (hub->intfdev,
 608			"%s failed (err = %d)\n", __func__, ret);
 609	else {
 610		*status = le16_to_cpu(hub->status->hub.wHubStatus);
 611		*change = le16_to_cpu(hub->status->hub.wHubChange); 
 612		ret = 0;
 613	}
 614	mutex_unlock(&hub->status_mutex);
 615	return ret;
 616}
 617
 618static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
 619{
 620	struct usb_device *hdev = hub->hdev;
 621	int ret = 0;
 622
 623	if (hdev->children[port1-1] && set_state)
 624		usb_set_device_state(hdev->children[port1-1],
 625				USB_STATE_NOTATTACHED);
 626	if (!hub->error && !hub_is_superspeed(hub->hdev))
 627		ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
 628	if (ret)
 629		dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
 630				port1, ret);
 631	return ret;
 632}
 633
 634/*
 635 * Disable a port and mark a logical connect-change event, so that some
 636 * time later khubd will disconnect() any existing usb_device on the port
 637 * and will re-enumerate if there actually is a device attached.
 638 */
 639static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
 640{
 641	dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
 642	hub_port_disable(hub, port1, 1);
 643
 644	/* FIXME let caller ask to power down the port:
 645	 *  - some devices won't enumerate without a VBUS power cycle
 646	 *  - SRP saves power that way
 647	 *  - ... new call, TBD ...
 648	 * That's easy if this hub can switch power per-port, and
 649	 * khubd reactivates the port later (timer, SRP, etc).
 650	 * Powerdown must be optional, because of reset/DFU.
 651	 */
 652
 653	set_bit(port1, hub->change_bits);
 654 	kick_khubd(hub);
 655}
 656
 657/**
 658 * usb_remove_device - disable a device's port on its parent hub
 659 * @udev: device to be disabled and removed
 660 * Context: @udev locked, must be able to sleep.
 661 *
 662 * After @udev's port has been disabled, khubd is notified and it will
 663 * see that the device has been disconnected.  When the device is
 664 * physically unplugged and something is plugged in, the events will
 665 * be received and processed normally.
 666 */
 667int usb_remove_device(struct usb_device *udev)
 668{
 669	struct usb_hub *hub;
 670	struct usb_interface *intf;
 671
 672	if (!udev->parent)	/* Can't remove a root hub */
 673		return -EINVAL;
 674	hub = hdev_to_hub(udev->parent);
 675	intf = to_usb_interface(hub->intfdev);
 676
 677	usb_autopm_get_interface(intf);
 678	set_bit(udev->portnum, hub->removed_bits);
 679	hub_port_logical_disconnect(hub, udev->portnum);
 680	usb_autopm_put_interface(intf);
 681	return 0;
 682}
 683
 684enum hub_activation_type {
 685	HUB_INIT, HUB_INIT2, HUB_INIT3,		/* INITs must come first */
 686	HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
 687};
 688
 689static void hub_init_func2(struct work_struct *ws);
 690static void hub_init_func3(struct work_struct *ws);
 691
 692static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
 693{
 694	struct usb_device *hdev = hub->hdev;
 695	struct usb_hcd *hcd;
 696	int ret;
 697	int port1;
 698	int status;
 699	bool need_debounce_delay = false;
 700	unsigned delay;
 701
 702	/* Continue a partial initialization */
 703	if (type == HUB_INIT2)
 704		goto init2;
 705	if (type == HUB_INIT3)
 706		goto init3;
 707
 708	/* After a resume, port power should still be on.
 709	 * For any other type of activation, turn it on.
 710	 */
 711	if (type != HUB_RESUME) {
 712
 713		/* Speed up system boot by using a delayed_work for the
 714		 * hub's initial power-up delays.  This is pretty awkward
 715		 * and the implementation looks like a home-brewed sort of
 716		 * setjmp/longjmp, but it saves at least 100 ms for each
 717		 * root hub (assuming usbcore is compiled into the kernel
 718		 * rather than as a module).  It adds up.
 719		 *
 720		 * This can't be done for HUB_RESUME or HUB_RESET_RESUME
 721		 * because for those activation types the ports have to be
 722		 * operational when we return.  In theory this could be done
 723		 * for HUB_POST_RESET, but it's easier not to.
 724		 */
 725		if (type == HUB_INIT) {
 726			delay = hub_power_on(hub, false);
 727			PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func2);
 728			schedule_delayed_work(&hub->init_work,
 729					msecs_to_jiffies(delay));
 730
 731			/* Suppress autosuspend until init is done */
 732			usb_autopm_get_interface_no_resume(
 733					to_usb_interface(hub->intfdev));
 734			return;		/* Continues at init2: below */
 735		} else if (type == HUB_RESET_RESUME) {
 736			/* The internal host controller state for the hub device
 737			 * may be gone after a host power loss on system resume.
 738			 * Update the device's info so the HW knows it's a hub.
 739			 */
 740			hcd = bus_to_hcd(hdev->bus);
 741			if (hcd->driver->update_hub_device) {
 742				ret = hcd->driver->update_hub_device(hcd, hdev,
 743						&hub->tt, GFP_NOIO);
 744				if (ret < 0) {
 745					dev_err(hub->intfdev, "Host not "
 746							"accepting hub info "
 747							"update.\n");
 748					dev_err(hub->intfdev, "LS/FS devices "
 749							"and hubs may not work "
 750							"under this hub\n.");
 751				}
 752			}
 753			hub_power_on(hub, true);
 754		} else {
 755			hub_power_on(hub, true);
 756		}
 757	}
 758 init2:
 759
 760	/* Check each port and set hub->change_bits to let khubd know
 761	 * which ports need attention.
 762	 */
 763	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
 764		struct usb_device *udev = hdev->children[port1-1];
 765		u16 portstatus, portchange;
 766
 767		portstatus = portchange = 0;
 768		status = hub_port_status(hub, port1, &portstatus, &portchange);
 769		if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
 770			dev_dbg(hub->intfdev,
 771					"port %d: status %04x change %04x\n",
 772					port1, portstatus, portchange);
 773
 774		/* After anything other than HUB_RESUME (i.e., initialization
 775		 * or any sort of reset), every port should be disabled.
 776		 * Unconnected ports should likewise be disabled (paranoia),
 777		 * and so should ports for which we have no usb_device.
 778		 */
 779		if ((portstatus & USB_PORT_STAT_ENABLE) && (
 780				type != HUB_RESUME ||
 781				!(portstatus & USB_PORT_STAT_CONNECTION) ||
 782				!udev ||
 783				udev->state == USB_STATE_NOTATTACHED)) {
 784			/*
 785			 * USB3 protocol ports will automatically transition
 786			 * to Enabled state when detect an USB3.0 device attach.
 787			 * Do not disable USB3 protocol ports.
 788			 */
 789			if (!hub_is_superspeed(hdev)) {
 790				clear_port_feature(hdev, port1,
 791						   USB_PORT_FEAT_ENABLE);
 792				portstatus &= ~USB_PORT_STAT_ENABLE;
 793			} else {
 794				/* Pretend that power was lost for USB3 devs */
 795				portstatus &= ~USB_PORT_STAT_ENABLE;
 796			}
 797		}
 798
 799		/* Clear status-change flags; we'll debounce later */
 800		if (portchange & USB_PORT_STAT_C_CONNECTION) {
 801			need_debounce_delay = true;
 802			clear_port_feature(hub->hdev, port1,
 803					USB_PORT_FEAT_C_CONNECTION);
 804		}
 805		if (portchange & USB_PORT_STAT_C_ENABLE) {
 806			need_debounce_delay = true;
 807			clear_port_feature(hub->hdev, port1,
 808					USB_PORT_FEAT_C_ENABLE);
 809		}
 810		if (portchange & USB_PORT_STAT_C_LINK_STATE) {
 811			need_debounce_delay = true;
 812			clear_port_feature(hub->hdev, port1,
 813					USB_PORT_FEAT_C_PORT_LINK_STATE);
 814		}
 815
 816		if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
 817				hub_is_superspeed(hub->hdev)) {
 818			need_debounce_delay = true;
 819			clear_port_feature(hub->hdev, port1,
 820					USB_PORT_FEAT_C_BH_PORT_RESET);
 821		}
 822		/* We can forget about a "removed" device when there's a
 823		 * physical disconnect or the connect status changes.
 824		 */
 825		if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
 826				(portchange & USB_PORT_STAT_C_CONNECTION))
 827			clear_bit(port1, hub->removed_bits);
 828
 829		if (!udev || udev->state == USB_STATE_NOTATTACHED) {
 830			/* Tell khubd to disconnect the device or
 831			 * check for a new connection
 832			 */
 833			if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
 834				set_bit(port1, hub->change_bits);
 835
 836		} else if (portstatus & USB_PORT_STAT_ENABLE) {
 837			/* The power session apparently survived the resume.
 838			 * If there was an overcurrent or suspend change
 839			 * (i.e., remote wakeup request), have khubd
 840			 * take care of it.
 841			 */
 842			if (portchange)
 843				set_bit(port1, hub->change_bits);
 844
 845		} else if (udev->persist_enabled) {
 846#ifdef CONFIG_PM
 847			udev->reset_resume = 1;
 848#endif
 849			set_bit(port1, hub->change_bits);
 850
 851		} else {
 852			/* The power session is gone; tell khubd */
 853			usb_set_device_state(udev, USB_STATE_NOTATTACHED);
 854			set_bit(port1, hub->change_bits);
 855		}
 856	}
 857
 858	/* If no port-status-change flags were set, we don't need any
 859	 * debouncing.  If flags were set we can try to debounce the
 860	 * ports all at once right now, instead of letting khubd do them
 861	 * one at a time later on.
 862	 *
 863	 * If any port-status changes do occur during this delay, khubd
 864	 * will see them later and handle them normally.
 865	 */
 866	if (need_debounce_delay) {
 867		delay = HUB_DEBOUNCE_STABLE;
 868
 869		/* Don't do a long sleep inside a workqueue routine */
 870		if (type == HUB_INIT2) {
 871			PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func3);
 872			schedule_delayed_work(&hub->init_work,
 873					msecs_to_jiffies(delay));
 874			return;		/* Continues at init3: below */
 875		} else {
 876			msleep(delay);
 877		}
 878	}
 879 init3:
 880	hub->quiescing = 0;
 881
 882	status = usb_submit_urb(hub->urb, GFP_NOIO);
 883	if (status < 0)
 884		dev_err(hub->intfdev, "activate --> %d\n", status);
 885	if (hub->has_indicators && blinkenlights)
 886		schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 887
 888	/* Scan all ports that need attention */
 889	kick_khubd(hub);
 890
 891	/* Allow autosuspend if it was suppressed */
 892	if (type <= HUB_INIT3)
 893		usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
 894}
 895
 896/* Implement the continuations for the delays above */
 897static void hub_init_func2(struct work_struct *ws)
 898{
 899	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
 900
 901	hub_activate(hub, HUB_INIT2);
 902}
 903
 904static void hub_init_func3(struct work_struct *ws)
 905{
 906	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
 907
 908	hub_activate(hub, HUB_INIT3);
 909}
 910
 911enum hub_quiescing_type {
 912	HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
 913};
 914
 915static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
 916{
 917	struct usb_device *hdev = hub->hdev;
 918	int i;
 919
 920	cancel_delayed_work_sync(&hub->init_work);
 921
 922	/* khubd and related activity won't re-trigger */
 923	hub->quiescing = 1;
 924
 925	if (type != HUB_SUSPEND) {
 926		/* Disconnect all the children */
 927		for (i = 0; i < hdev->maxchild; ++i) {
 928			if (hdev->children[i])
 929				usb_disconnect(&hdev->children[i]);
 930		}
 931	}
 932
 933	/* Stop khubd and related activity */
 934	usb_kill_urb(hub->urb);
 935	if (hub->has_indicators)
 936		cancel_delayed_work_sync(&hub->leds);
 937	if (hub->tt.hub)
 938		cancel_work_sync(&hub->tt.clear_work);
 939}
 940
 941/* caller has locked the hub device */
 942static int hub_pre_reset(struct usb_interface *intf)
 943{
 944	struct usb_hub *hub = usb_get_intfdata(intf);
 945
 946	hub_quiesce(hub, HUB_PRE_RESET);
 947	return 0;
 948}
 949
 950/* caller has locked the hub device */
 951static int hub_post_reset(struct usb_interface *intf)
 952{
 953	struct usb_hub *hub = usb_get_intfdata(intf);
 954
 955	hub_activate(hub, HUB_POST_RESET);
 956	return 0;
 957}
 958
 959static int hub_configure(struct usb_hub *hub,
 960	struct usb_endpoint_descriptor *endpoint)
 961{
 962	struct usb_hcd *hcd;
 963	struct usb_device *hdev = hub->hdev;
 964	struct device *hub_dev = hub->intfdev;
 965	u16 hubstatus, hubchange;
 966	u16 wHubCharacteristics;
 967	unsigned int pipe;
 968	int maxp, ret;
 969	char *message = "out of memory";
 970
 971	hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
 972	if (!hub->buffer) {
 973		ret = -ENOMEM;
 974		goto fail;
 975	}
 976
 977	hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
 978	if (!hub->status) {
 979		ret = -ENOMEM;
 980		goto fail;
 981	}
 982	mutex_init(&hub->status_mutex);
 983
 984	hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
 985	if (!hub->descriptor) {
 986		ret = -ENOMEM;
 987		goto fail;
 988	}
 989
 990	if (hub_is_superspeed(hdev) && (hdev->parent != NULL)) {
 991		ret = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 992				HUB_SET_DEPTH, USB_RT_HUB,
 993				hdev->level - 1, 0, NULL, 0,
 994				USB_CTRL_SET_TIMEOUT);
 995
 996		if (ret < 0) {
 997			message = "can't set hub depth";
 998			goto fail;
 999		}
1000	}
1001
1002	/* Request the entire hub descriptor.
1003	 * hub->descriptor can handle USB_MAXCHILDREN ports,
1004	 * but the hub can/will return fewer bytes here.
1005	 */
1006	ret = get_hub_descriptor(hdev, hub->descriptor);
1007	if (ret < 0) {
1008		message = "can't read hub descriptor";
1009		goto fail;
1010	} else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
1011		message = "hub has too many ports!";
1012		ret = -ENODEV;
1013		goto fail;
1014	}
1015
1016	hdev->maxchild = hub->descriptor->bNbrPorts;
1017	dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
1018		(hdev->maxchild == 1) ? "" : "s");
1019
1020	hub->port_owners = kzalloc(hdev->maxchild * sizeof(void *), GFP_KERNEL);
1021	if (!hub->port_owners) {
1022		ret = -ENOMEM;
1023		goto fail;
1024	}
1025
1026	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
1027
1028	/* FIXME for USB 3.0, skip for now */
1029	if ((wHubCharacteristics & HUB_CHAR_COMPOUND) &&
1030			!(hub_is_superspeed(hdev))) {
1031		int	i;
1032		char	portstr [USB_MAXCHILDREN + 1];
1033
1034		for (i = 0; i < hdev->maxchild; i++)
1035			portstr[i] = hub->descriptor->u.hs.DeviceRemovable
1036				    [((i + 1) / 8)] & (1 << ((i + 1) % 8))
1037				? 'F' : 'R';
1038		portstr[hdev->maxchild] = 0;
1039		dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
1040	} else
1041		dev_dbg(hub_dev, "standalone hub\n");
1042
1043	switch (wHubCharacteristics & HUB_CHAR_LPSM) {
1044		case 0x00:
1045			dev_dbg(hub_dev, "ganged power switching\n");
1046			break;
1047		case 0x01:
1048			dev_dbg(hub_dev, "individual port power switching\n");
1049			break;
1050		case 0x02:
1051		case 0x03:
1052			dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
1053			break;
1054	}
1055
1056	switch (wHubCharacteristics & HUB_CHAR_OCPM) {
1057		case 0x00:
1058			dev_dbg(hub_dev, "global over-current protection\n");
1059			break;
1060		case 0x08:
1061			dev_dbg(hub_dev, "individual port over-current protection\n");
1062			break;
1063		case 0x10:
1064		case 0x18:
1065			dev_dbg(hub_dev, "no over-current protection\n");
1066                        break;
1067	}
1068
1069	spin_lock_init (&hub->tt.lock);
1070	INIT_LIST_HEAD (&hub->tt.clear_list);
1071	INIT_WORK(&hub->tt.clear_work, hub_tt_work);
1072	switch (hdev->descriptor.bDeviceProtocol) {
1073		case 0:
1074			break;
1075		case 1:
1076			dev_dbg(hub_dev, "Single TT\n");
1077			hub->tt.hub = hdev;
1078			break;
1079		case 2:
1080			ret = usb_set_interface(hdev, 0, 1);
1081			if (ret == 0) {
1082				dev_dbg(hub_dev, "TT per port\n");
1083				hub->tt.multi = 1;
1084			} else
1085				dev_err(hub_dev, "Using single TT (err %d)\n",
1086					ret);
1087			hub->tt.hub = hdev;
1088			break;
1089		case 3:
1090			/* USB 3.0 hubs don't have a TT */
1091			break;
1092		default:
1093			dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
1094				hdev->descriptor.bDeviceProtocol);
1095			break;
1096	}
1097
1098	/* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
1099	switch (wHubCharacteristics & HUB_CHAR_TTTT) {
1100		case HUB_TTTT_8_BITS:
1101			if (hdev->descriptor.bDeviceProtocol != 0) {
1102				hub->tt.think_time = 666;
1103				dev_dbg(hub_dev, "TT requires at most %d "
1104						"FS bit times (%d ns)\n",
1105					8, hub->tt.think_time);
1106			}
1107			break;
1108		case HUB_TTTT_16_BITS:
1109			hub->tt.think_time = 666 * 2;
1110			dev_dbg(hub_dev, "TT requires at most %d "
1111					"FS bit times (%d ns)\n",
1112				16, hub->tt.think_time);
1113			break;
1114		case HUB_TTTT_24_BITS:
1115			hub->tt.think_time = 666 * 3;
1116			dev_dbg(hub_dev, "TT requires at most %d "
1117					"FS bit times (%d ns)\n",
1118				24, hub->tt.think_time);
1119			break;
1120		case HUB_TTTT_32_BITS:
1121			hub->tt.think_time = 666 * 4;
1122			dev_dbg(hub_dev, "TT requires at most %d "
1123					"FS bit times (%d ns)\n",
1124				32, hub->tt.think_time);
1125			break;
1126	}
1127
1128	/* probe() zeroes hub->indicator[] */
1129	if (wHubCharacteristics & HUB_CHAR_PORTIND) {
1130		hub->has_indicators = 1;
1131		dev_dbg(hub_dev, "Port indicators are supported\n");
1132	}
1133
1134	dev_dbg(hub_dev, "power on to power good time: %dms\n",
1135		hub->descriptor->bPwrOn2PwrGood * 2);
1136
1137	/* power budgeting mostly matters with bus-powered hubs,
1138	 * and battery-powered root hubs (may provide just 8 mA).
1139	 */
1140	ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
1141	if (ret < 2) {
1142		message = "can't get hub status";
1143		goto fail;
1144	}
1145	le16_to_cpus(&hubstatus);
1146	if (hdev == hdev->bus->root_hub) {
1147		if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
1148			hub->mA_per_port = 500;
1149		else {
1150			hub->mA_per_port = hdev->bus_mA;
1151			hub->limited_power = 1;
1152		}
1153	} else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1154		dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
1155			hub->descriptor->bHubContrCurrent);
1156		hub->limited_power = 1;
1157		if (hdev->maxchild > 0) {
1158			int remaining = hdev->bus_mA -
1159					hub->descriptor->bHubContrCurrent;
1160
1161			if (remaining < hdev->maxchild * 100)
1162				dev_warn(hub_dev,
1163					"insufficient power available "
1164					"to use all downstream ports\n");
1165			hub->mA_per_port = 100;		/* 7.2.1.1 */
1166		}
1167	} else {	/* Self-powered external hub */
1168		/* FIXME: What about battery-powered external hubs that
1169		 * provide less current per port? */
1170		hub->mA_per_port = 500;
1171	}
1172	if (hub->mA_per_port < 500)
1173		dev_dbg(hub_dev, "%umA bus power budget for each child\n",
1174				hub->mA_per_port);
1175
1176	/* Update the HCD's internal representation of this hub before khubd
1177	 * starts getting port status changes for devices under the hub.
1178	 */
1179	hcd = bus_to_hcd(hdev->bus);
1180	if (hcd->driver->update_hub_device) {
1181		ret = hcd->driver->update_hub_device(hcd, hdev,
1182				&hub->tt, GFP_KERNEL);
1183		if (ret < 0) {
1184			message = "can't update HCD hub info";
1185			goto fail;
1186		}
1187	}
1188
1189	ret = hub_hub_status(hub, &hubstatus, &hubchange);
1190	if (ret < 0) {
1191		message = "can't get hub status";
1192		goto fail;
1193	}
1194
1195	/* local power status reports aren't always correct */
1196	if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
1197		dev_dbg(hub_dev, "local power source is %s\n",
1198			(hubstatus & HUB_STATUS_LOCAL_POWER)
1199			? "lost (inactive)" : "good");
1200
1201	if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
1202		dev_dbg(hub_dev, "%sover-current condition exists\n",
1203			(hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
1204
1205	/* set up the interrupt endpoint
1206	 * We use the EP's maxpacket size instead of (PORTS+1+7)/8
1207	 * bytes as USB2.0[11.12.3] says because some hubs are known
1208	 * to send more data (and thus cause overflow). For root hubs,
1209	 * maxpktsize is defined in hcd.c's fake endpoint descriptors
1210	 * to be big enough for at least USB_MAXCHILDREN ports. */
1211	pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
1212	maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
1213
1214	if (maxp > sizeof(*hub->buffer))
1215		maxp = sizeof(*hub->buffer);
1216
1217	hub->urb = usb_alloc_urb(0, GFP_KERNEL);
1218	if (!hub->urb) {
1219		ret = -ENOMEM;
1220		goto fail;
1221	}
1222
1223	usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1224		hub, endpoint->bInterval);
1225
1226	/* maybe cycle the hub leds */
1227	if (hub->has_indicators && blinkenlights)
1228		hub->indicator [0] = INDICATOR_CYCLE;
1229
1230	hub_activate(hub, HUB_INIT);
1231	return 0;
1232
1233fail:
1234	dev_err (hub_dev, "config failed, %s (err %d)\n",
1235			message, ret);
1236	/* hub_disconnect() frees urb and descriptor */
1237	return ret;
1238}
1239
1240static void hub_release(struct kref *kref)
1241{
1242	struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1243
1244	usb_put_intf(to_usb_interface(hub->intfdev));
1245	kfree(hub);
1246}
1247
1248static unsigned highspeed_hubs;
1249
1250static void hub_disconnect(struct usb_interface *intf)
1251{
1252	struct usb_hub *hub = usb_get_intfdata (intf);
1253
1254	/* Take the hub off the event list and don't let it be added again */
1255	spin_lock_irq(&hub_event_lock);
1256	if (!list_empty(&hub->event_list)) {
1257		list_del_init(&hub->event_list);
1258		usb_autopm_put_interface_no_suspend(intf);
1259	}
1260	hub->disconnected = 1;
1261	spin_unlock_irq(&hub_event_lock);
1262
1263	/* Disconnect all children and quiesce the hub */
1264	hub->error = 0;
1265	hub_quiesce(hub, HUB_DISCONNECT);
1266
1267	usb_set_intfdata (intf, NULL);
1268	hub->hdev->maxchild = 0;
1269
1270	if (hub->hdev->speed == USB_SPEED_HIGH)
1271		highspeed_hubs--;
1272
1273	usb_free_urb(hub->urb);
1274	kfree(hub->port_owners);
1275	kfree(hub->descriptor);
1276	kfree(hub->status);
1277	kfree(hub->buffer);
1278
1279	kref_put(&hub->kref, hub_release);
1280}
1281
1282static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1283{
1284	struct usb_host_interface *desc;
1285	struct usb_endpoint_descriptor *endpoint;
1286	struct usb_device *hdev;
1287	struct usb_hub *hub;
1288
1289	desc = intf->cur_altsetting;
1290	hdev = interface_to_usbdev(intf);
1291
1292	/* Hubs have proper suspend/resume support.  USB 3.0 device suspend is
1293	 * different from USB 2.0/1.1 device suspend, and unfortunately we
1294	 * don't support it yet.  So leave autosuspend disabled for USB 3.0
1295	 * external hubs for now.  Enable autosuspend for USB 3.0 roothubs,
1296	 * since that isn't a "real" hub.
1297	 */
1298	if (!hub_is_superspeed(hdev) || !hdev->parent)
1299		usb_enable_autosuspend(hdev);
1300
1301	if (hdev->level == MAX_TOPO_LEVEL) {
1302		dev_err(&intf->dev,
1303			"Unsupported bus topology: hub nested too deep\n");
1304		return -E2BIG;
1305	}
1306
1307#ifdef	CONFIG_USB_OTG_BLACKLIST_HUB
1308	if (hdev->parent) {
1309		dev_warn(&intf->dev, "ignoring external hub\n");
1310		return -ENODEV;
1311	}
1312#endif
1313
1314	/* Some hubs have a subclass of 1, which AFAICT according to the */
1315	/*  specs is not defined, but it works */
1316	if ((desc->desc.bInterfaceSubClass != 0) &&
1317	    (desc->desc.bInterfaceSubClass != 1)) {
1318descriptor_error:
1319		dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
1320		return -EIO;
1321	}
1322
1323	/* Multiple endpoints? What kind of mutant ninja-hub is this? */
1324	if (desc->desc.bNumEndpoints != 1)
1325		goto descriptor_error;
1326
1327	endpoint = &desc->endpoint[0].desc;
1328
1329	/* If it's not an interrupt in endpoint, we'd better punt! */
1330	if (!usb_endpoint_is_int_in(endpoint))
1331		goto descriptor_error;
1332
1333	/* We found a hub */
1334	dev_info (&intf->dev, "USB hub found\n");
1335
1336	hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1337	if (!hub) {
1338		dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
1339		return -ENOMEM;
1340	}
1341
1342	kref_init(&hub->kref);
1343	INIT_LIST_HEAD(&hub->event_list);
1344	hub->intfdev = &intf->dev;
1345	hub->hdev = hdev;
1346	INIT_DELAYED_WORK(&hub->leds, led_work);
1347	INIT_DELAYED_WORK(&hub->init_work, NULL);
1348	usb_get_intf(intf);
1349
1350	usb_set_intfdata (intf, hub);
1351	intf->needs_remote_wakeup = 1;
1352
1353	if (hdev->speed == USB_SPEED_HIGH)
1354		highspeed_hubs++;
1355
1356	if (hub_configure(hub, endpoint) >= 0)
1357		return 0;
1358
1359	hub_disconnect (intf);
1360	return -ENODEV;
1361}
1362
1363/* No BKL needed */
1364static int
1365hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1366{
1367	struct usb_device *hdev = interface_to_usbdev (intf);
1368
1369	/* assert ifno == 0 (part of hub spec) */
1370	switch (code) {
1371	case USBDEVFS_HUB_PORTINFO: {
1372		struct usbdevfs_hub_portinfo *info = user_data;
1373		int i;
1374
1375		spin_lock_irq(&device_state_lock);
1376		if (hdev->devnum <= 0)
1377			info->nports = 0;
1378		else {
1379			info->nports = hdev->maxchild;
1380			for (i = 0; i < info->nports; i++) {
1381				if (hdev->children[i] == NULL)
1382					info->port[i] = 0;
1383				else
1384					info->port[i] =
1385						hdev->children[i]->devnum;
1386			}
1387		}
1388		spin_unlock_irq(&device_state_lock);
1389
1390		return info->nports + 1;
1391		}
1392
1393	default:
1394		return -ENOSYS;
1395	}
1396}
1397
1398/*
1399 * Allow user programs to claim ports on a hub.  When a device is attached
1400 * to one of these "claimed" ports, the program will "own" the device.
1401 */
1402static int find_port_owner(struct usb_device *hdev, unsigned port1,
1403		void ***ppowner)
1404{
1405	if (hdev->state == USB_STATE_NOTATTACHED)
1406		return -ENODEV;
1407	if (port1 == 0 || port1 > hdev->maxchild)
1408		return -EINVAL;
1409
1410	/* This assumes that devices not managed by the hub driver
1411	 * will always have maxchild equal to 0.
1412	 */
1413	*ppowner = &(hdev_to_hub(hdev)->port_owners[port1 - 1]);
1414	return 0;
1415}
1416
1417/* In the following three functions, the caller must hold hdev's lock */
1418int usb_hub_claim_port(struct usb_device *hdev, unsigned port1, void *owner)
1419{
1420	int rc;
1421	void **powner;
1422
1423	rc = find_port_owner(hdev, port1, &powner);
1424	if (rc)
1425		return rc;
1426	if (*powner)
1427		return -EBUSY;
1428	*powner = owner;
1429	return rc;
1430}
1431
1432int usb_hub_release_port(struct usb_device *hdev, unsigned port1, void *owner)
1433{
1434	int rc;
1435	void **powner;
1436
1437	rc = find_port_owner(hdev, port1, &powner);
1438	if (rc)
1439		return rc;
1440	if (*powner != owner)
1441		return -ENOENT;
1442	*powner = NULL;
1443	return rc;
1444}
1445
1446void usb_hub_release_all_ports(struct usb_device *hdev, void *owner)
1447{
1448	int n;
1449	void **powner;
1450
1451	n = find_port_owner(hdev, 1, &powner);
1452	if (n == 0) {
1453		for (; n < hdev->maxchild; (++n, ++powner)) {
1454			if (*powner == owner)
1455				*powner = NULL;
1456		}
1457	}
1458}
1459
1460/* The caller must hold udev's lock */
1461bool usb_device_is_owned(struct usb_device *udev)
1462{
1463	struct usb_hub *hub;
1464
1465	if (udev->state == USB_STATE_NOTATTACHED || !udev->parent)
1466		return false;
1467	hub = hdev_to_hub(udev->parent);
1468	return !!hub->port_owners[udev->portnum - 1];
1469}
1470
1471
1472static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1473{
1474	int i;
1475
1476	for (i = 0; i < udev->maxchild; ++i) {
1477		if (udev->children[i])
1478			recursively_mark_NOTATTACHED(udev->children[i]);
1479	}
1480	if (udev->state == USB_STATE_SUSPENDED)
1481		udev->active_duration -= jiffies;
1482	udev->state = USB_STATE_NOTATTACHED;
1483}
1484
1485/**
1486 * usb_set_device_state - change a device's current state (usbcore, hcds)
1487 * @udev: pointer to device whose state should be changed
1488 * @new_state: new state value to be stored
1489 *
1490 * udev->state is _not_ fully protected by the device lock.  Although
1491 * most transitions are made only while holding the lock, the state can
1492 * can change to USB_STATE_NOTATTACHED at almost any time.  This
1493 * is so that devices can be marked as disconnected as soon as possible,
1494 * without having to wait for any semaphores to be released.  As a result,
1495 * all changes to any device's state must be protected by the
1496 * device_state_lock spinlock.
1497 *
1498 * Once a device has been added to the device tree, all changes to its state
1499 * should be made using this routine.  The state should _not_ be set directly.
1500 *
1501 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1502 * Otherwise udev->state is set to new_state, and if new_state is
1503 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1504 * to USB_STATE_NOTATTACHED.
1505 */
1506void usb_set_device_state(struct usb_device *udev,
1507		enum usb_device_state new_state)
1508{
1509	unsigned long flags;
1510	int wakeup = -1;
1511
1512	spin_lock_irqsave(&device_state_lock, flags);
1513	if (udev->state == USB_STATE_NOTATTACHED)
1514		;	/* do nothing */
1515	else if (new_state != USB_STATE_NOTATTACHED) {
1516
1517		/* root hub wakeup capabilities are managed out-of-band
1518		 * and may involve silicon errata ... ignore them here.
1519		 */
1520		if (udev->parent) {
1521			if (udev->state == USB_STATE_SUSPENDED
1522					|| new_state == USB_STATE_SUSPENDED)
1523				;	/* No change to wakeup settings */
1524			else if (new_state == USB_STATE_CONFIGURED)
1525				wakeup = udev->actconfig->desc.bmAttributes
1526					 & USB_CONFIG_ATT_WAKEUP;
1527			else
1528				wakeup = 0;
1529		}
1530		if (udev->state == USB_STATE_SUSPENDED &&
1531			new_state != USB_STATE_SUSPENDED)
1532			udev->active_duration -= jiffies;
1533		else if (new_state == USB_STATE_SUSPENDED &&
1534				udev->state != USB_STATE_SUSPENDED)
1535			udev->active_duration += jiffies;
1536		udev->state = new_state;
1537	} else
1538		recursively_mark_NOTATTACHED(udev);
1539	spin_unlock_irqrestore(&device_state_lock, flags);
1540	if (wakeup >= 0)
1541		device_set_wakeup_capable(&udev->dev, wakeup);
1542}
1543EXPORT_SYMBOL_GPL(usb_set_device_state);
1544
1545/*
1546 * Choose a device number.
1547 *
1548 * Device numbers are used as filenames in usbfs.  On USB-1.1 and
1549 * USB-2.0 buses they are also used as device addresses, however on
1550 * USB-3.0 buses the address is assigned by the controller hardware
1551 * and it usually is not the same as the device number.
1552 *
1553 * WUSB devices are simple: they have no hubs behind, so the mapping
1554 * device <-> virtual port number becomes 1:1. Why? to simplify the
1555 * life of the device connection logic in
1556 * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
1557 * handshake we need to assign a temporary address in the unauthorized
1558 * space. For simplicity we use the first virtual port number found to
1559 * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
1560 * and that becomes it's address [X < 128] or its unauthorized address
1561 * [X | 0x80].
1562 *
1563 * We add 1 as an offset to the one-based USB-stack port number
1564 * (zero-based wusb virtual port index) for two reasons: (a) dev addr
1565 * 0 is reserved by USB for default address; (b) Linux's USB stack
1566 * uses always #1 for the root hub of the controller. So USB stack's
1567 * port #1, which is wusb virtual-port #0 has address #2.
1568 *
1569 * Devices connected under xHCI are not as simple.  The host controller
1570 * supports virtualization, so the hardware assigns device addresses and
1571 * the HCD must setup data structures before issuing a set address
1572 * command to the hardware.
1573 */
1574static void choose_devnum(struct usb_device *udev)
1575{
1576	int		devnum;
1577	struct usb_bus	*bus = udev->bus;
1578
1579	/* If khubd ever becomes multithreaded, this will need a lock */
1580	if (udev->wusb) {
1581		devnum = udev->portnum + 1;
1582		BUG_ON(test_bit(devnum, bus->devmap.devicemap));
1583	} else {
1584		/* Try to allocate the next devnum beginning at
1585		 * bus->devnum_next. */
1586		devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1587					    bus->devnum_next);
1588		if (devnum >= 128)
1589			devnum = find_next_zero_bit(bus->devmap.devicemap,
1590						    128, 1);
1591		bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1592	}
1593	if (devnum < 128) {
1594		set_bit(devnum, bus->devmap.devicemap);
1595		udev->devnum = devnum;
1596	}
1597}
1598
1599static void release_devnum(struct usb_device *udev)
1600{
1601	if (udev->devnum > 0) {
1602		clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1603		udev->devnum = -1;
1604	}
1605}
1606
1607static void update_devnum(struct usb_device *udev, int devnum)
1608{
1609	/* The address for a WUSB device is managed by wusbcore. */
1610	if (!udev->wusb)
1611		udev->devnum = devnum;
1612}
1613
1614static void hub_free_dev(struct usb_device *udev)
1615{
1616	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1617
1618	/* Root hubs aren't real devices, so don't free HCD resources */
1619	if (hcd->driver->free_dev && udev->parent)
1620		hcd->driver->free_dev(hcd, udev);
1621}
1622
1623/**
1624 * usb_disconnect - disconnect a device (usbcore-internal)
1625 * @pdev: pointer to device being disconnected
1626 * Context: !in_interrupt ()
1627 *
1628 * Something got disconnected. Get rid of it and all of its children.
1629 *
1630 * If *pdev is a normal device then the parent hub must already be locked.
1631 * If *pdev is a root hub then this routine will acquire the
1632 * usb_bus_list_lock on behalf of the caller.
1633 *
1634 * Only hub drivers (including virtual root hub drivers for host
1635 * controllers) should ever call this.
1636 *
1637 * This call is synchronous, and may not be used in an interrupt context.
1638 */
1639void usb_disconnect(struct usb_device **pdev)
1640{
1641	struct usb_device	*udev = *pdev;
1642	int			i;
1643	struct usb_hcd		*hcd = bus_to_hcd(udev->bus);
1644
1645	if (!udev) {
1646		pr_debug ("%s nodev\n", __func__);
1647		return;
1648	}
1649
1650	/* mark the device as inactive, so any further urb submissions for
1651	 * this device (and any of its children) will fail immediately.
1652	 * this quiesces everything except pending urbs.
1653	 */
1654	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1655	dev_info(&udev->dev, "USB disconnect, device number %d\n",
1656			udev->devnum);
1657
1658	usb_lock_device(udev);
1659
1660	/* Free up all the children before we remove this device */
1661	for (i = 0; i < USB_MAXCHILDREN; i++) {
1662		if (udev->children[i])
1663			usb_disconnect(&udev->children[i]);
1664	}
1665
1666	/* deallocate hcd/hardware state ... nuking all pending urbs and
1667	 * cleaning up all state associated with the current configuration
1668	 * so that the hardware is now fully quiesced.
1669	 */
1670	dev_dbg (&udev->dev, "unregistering device\n");
1671	mutex_lock(hcd->bandwidth_mutex);
1672	usb_disable_device(udev, 0);
1673	mutex_unlock(hcd->bandwidth_mutex);
1674	usb_hcd_synchronize_unlinks(udev);
1675
1676	usb_remove_ep_devs(&udev->ep0);
1677	usb_unlock_device(udev);
1678
1679	/* Unregister the device.  The device driver is responsible
1680	 * for de-configuring the device and invoking the remove-device
1681	 * notifier chain (used by usbfs and possibly others).
1682	 */
1683	device_del(&udev->dev);
1684
1685	/* Free the device number and delete the parent's children[]
1686	 * (or root_hub) pointer.
1687	 */
1688	release_devnum(udev);
1689
1690	/* Avoid races with recursively_mark_NOTATTACHED() */
1691	spin_lock_irq(&device_state_lock);
1692	*pdev = NULL;
1693	spin_unlock_irq(&device_state_lock);
1694
1695	hub_free_dev(udev);
1696
1697	put_device(&udev->dev);
1698}
1699
1700#ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
1701static void show_string(struct usb_device *udev, char *id, char *string)
1702{
1703	if (!string)
1704		return;
1705	dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1706}
1707
1708static void announce_device(struct usb_device *udev)
1709{
1710	dev_info(&udev->dev, "New USB device found, idVendor=%04x, idProduct=%04x\n",
1711		le16_to_cpu(udev->descriptor.idVendor),
1712		le16_to_cpu(udev->descriptor.idProduct));
1713	dev_info(&udev->dev,
1714		"New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
1715		udev->descriptor.iManufacturer,
1716		udev->descriptor.iProduct,
1717		udev->descriptor.iSerialNumber);
1718	show_string(udev, "Product", udev->product);
1719	show_string(udev, "Manufacturer", udev->manufacturer);
1720	show_string(udev, "SerialNumber", udev->serial);
1721}
1722#else
1723static inline void announce_device(struct usb_device *udev) { }
1724#endif
1725
1726#ifdef	CONFIG_USB_OTG
1727#include "otg_whitelist.h"
1728#endif
1729
1730/**
1731 * usb_enumerate_device_otg - FIXME (usbcore-internal)
1732 * @udev: newly addressed device (in ADDRESS state)
1733 *
1734 * Finish enumeration for On-The-Go devices
1735 */
1736static int usb_enumerate_device_otg(struct usb_device *udev)
1737{
1738	int err = 0;
1739
1740#ifdef	CONFIG_USB_OTG
1741	/*
1742	 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1743	 * to wake us after we've powered off VBUS; and HNP, switching roles
1744	 * "host" to "peripheral".  The OTG descriptor helps figure this out.
1745	 */
1746	if (!udev->bus->is_b_host
1747			&& udev->config
1748			&& udev->parent == udev->

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