drivers/usb/core/hub.c

   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/smp_lock.h>
  20 #include <linux/ioctl.h>
  21 #include <linux/usb.h>
  22 #include <linux/usbdevice_fs.h>
  23 #include <linux/kthread.h>
  24 #include <linux/mutex.h>
  25 #include <linux/freezer.h>
  26
  27 #include <asm/semaphore.h>
  28 #include <asm/uaccess.h>
  29 #include <asm/byteorder.h>
  30
  31 #include "usb.h"
  32 #include "hcd.h"
  33 #include "hub.h"
  34
  35 struct usb_hub {
  36         struct device           *intfdev;       /* the "interface" device */
  37         struct usb_device       *hdev;
  38         struct urb              *urb;           /* for interrupt polling pipe */
  39
  40         /* buffer for urb ... with extra space in case of babble */
  41         char                    (*buffer)[8];
  42         dma_addr_t              buffer_dma;     /* DMA address for buffer */
  43         union {
  44                 struct usb_hub_status   hub;
  45                 struct usb_port_status  port;
  46         }                       *status;        /* buffer for status reports */
  47         struct mutex            status_mutex;   /* for the status buffer */
  48
  49         int                     error;          /* last reported error */
  50         int                     nerrors;        /* track consecutive errors */
  51
  52         struct list_head        event_list;     /* hubs w/data or errs ready */
  53         unsigned long           event_bits[1];  /* status change bitmask */
  54         unsigned long           change_bits[1]; /* ports with logical connect
  55                                                         status change */
  56         unsigned long           busy_bits[1];   /* ports being reset or
  57                                                         resumed */
  58 #if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
  59 #error event_bits[] is too short!
  60 #endif
  61
  62         struct usb_hub_descriptor *descriptor;  /* class descriptor */
  63         struct usb_tt           tt;             /* Transaction Translator */
  64
  65         unsigned                mA_per_port;    /* current for each child */
  66
  67         unsigned                limited_power:1;
  68         unsigned                quiescing:1;
  69         unsigned                activating:1;
  70
  71         unsigned                has_indicators:1;
  72         u8                      indicator[USB_MAXCHILDREN];
  73         struct delayed_work     leds;
  74 };
  75
  76
  77 /* Protect struct usb_device->state and ->children members
  78  * Note: Both are also protected by ->dev.sem, except that ->state can
  79  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
  80 static DEFINE_SPINLOCK(device_state_lock);
  81
  82 /* khubd's worklist and its lock */
  83 static DEFINE_SPINLOCK(hub_event_lock);
  84 static LIST_HEAD(hub_event_list);       /* List of hubs needing servicing */
  85
  86 /* Wakes up khubd */
  87 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
  88
  89 static struct task_struct *khubd_task;
  90
  91 /* multithreaded probe logic */
  92 static int multithread_probe = 0;
  93
  94 /* cycle leds on hubs that aren't blinking for attention */
  95 static int blinkenlights = 0;
  96 module_param (blinkenlights, bool, S_IRUGO);
  97 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
  98
  99 /*
 100  * As of 2.6.10 we introduce a new USB device initialization scheme which
 101  * closely resembles the way Windows works.  Hopefully it will be compatible
 102  * with a wider range of devices than the old scheme.  However some previously
 103  * working devices may start giving rise to "device not accepting address"
 104  * errors; if that happens the user can try the old scheme by adjusting the
 105  * following module parameters.
 106  *
 107  * For maximum flexibility there are two boolean parameters to control the
 108  * hub driver's behavior.  On the first initialization attempt, if the
 109  * "old_scheme_first" parameter is set then the old scheme will be used,
 110  * otherwise the new scheme is used.  If that fails and "use_both_schemes"
 111  * is set, then the driver will make another attempt, using the other scheme.
 112  */
 113 static int old_scheme_first = 0;
 114 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
 115 MODULE_PARM_DESC(old_scheme_first,
 116                  "start with the old device initialization scheme");
 117
 118 static int use_both_schemes = 1;
 119 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
 120 MODULE_PARM_DESC(use_both_schemes,
 121                 "try the other device initialization scheme if the "
 122                 "first one fails");
 123
 124
 125 #ifdef  DEBUG
 126 static inline char *portspeed (int portstatus)
 127 {
 128         if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
 129                 return "480 Mb/s";
 130         else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
 131                 return "1.5 Mb/s";
 132         else
 133                 return "12 Mb/s";
 134 }
 135 #endif
 136
 137 /* Note that hdev or one of its children must be locked! */
 138 static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
 139 {
 140         return usb_get_intfdata(hdev->actconfig->interface[0]);
 141 }
 142
 143 /* USB 2.0 spec Section 11.24.4.5 */
 144 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
 145 {
 146         int i, ret;
 147
 148         for (i = 0; i < 3; i++) {
 149                 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 150                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
 151                         USB_DT_HUB << 8, 0, data, size,
 152                         USB_CTRL_GET_TIMEOUT);
 153                 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
 154                         return ret;
 155         }
 156         return -EINVAL;
 157 }
 158
 159 /*
 160  * USB 2.0 spec Section 11.24.2.1
 161  */
 162 static int clear_hub_feature(struct usb_device *hdev, int feature)
 163 {
 164         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 165                 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
 166 }
 167
 168 /*
 169  * USB 2.0 spec Section 11.24.2.2
 170  */
 171 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
 172 {
 173         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 174                 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
 175                 NULL, 0, 1000);
 176 }
 177
 178 /*
 179  * USB 2.0 spec Section 11.24.2.13
 180  */
 181 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
 182 {
 183         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 184                 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
 185                 NULL, 0, 1000);
 186 }
 187
 188 /*
 189  * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
 190  * for info about using port indicators
 191  */
 192 static void set_port_led(
 193         struct usb_hub *hub,
 194         int port1,
 195         int selector
 196 )
 197 {
 198         int status = set_port_feature(hub->hdev, (selector << 8) | port1,
 199                         USB_PORT_FEAT_INDICATOR);
 200         if (status < 0)
 201                 dev_dbg (hub->intfdev,
 202                         "port %d indicator %s status %d\n",
 203                         port1,
 204                         ({ char *s; switch (selector) {
 205                         case HUB_LED_AMBER: s = "amber"; break;
 206                         case HUB_LED_GREEN: s = "green"; break;
 207                         case HUB_LED_OFF: s = "off"; break;
 208                         case HUB_LED_AUTO: s = "auto"; break;
 209                         default: s = "??"; break;
 210                         }; s; }),
 211                         status);
 212 }
 213
 214 #define LED_CYCLE_PERIOD        ((2*HZ)/3)
 215
 216 static void led_work (struct work_struct *work)
 217 {
 218         struct usb_hub          *hub =
 219                 container_of(work, struct usb_hub, leds.work);
 220         struct usb_device       *hdev = hub->hdev;
 221         unsigned                i;
 222         unsigned                changed = 0;
 223         int                     cursor = -1;
 224
 225         if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
 226                 return;
 227
 228         for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
 229                 unsigned        selector, mode;
 230
 231                 /* 30%-50% duty cycle */
 232
 233                 switch (hub->indicator[i]) {
 234                 /* cycle marker */
 235                 case INDICATOR_CYCLE:
 236                         cursor = i;
 237                         selector = HUB_LED_AUTO;
 238                         mode = INDICATOR_AUTO;
 239                         break;
 240                 /* blinking green = sw attention */
 241                 case INDICATOR_GREEN_BLINK:
 242                         selector = HUB_LED_GREEN;
 243                         mode = INDICATOR_GREEN_BLINK_OFF;
 244                         break;
 245                 case INDICATOR_GREEN_BLINK_OFF:
 246                         selector = HUB_LED_OFF;
 247                         mode = INDICATOR_GREEN_BLINK;
 248                         break;
 249                 /* blinking amber = hw attention */
 250                 case INDICATOR_AMBER_BLINK:
 251                         selector = HUB_LED_AMBER;
 252                         mode = INDICATOR_AMBER_BLINK_OFF;
 253                         break;
 254                 case INDICATOR_AMBER_BLINK_OFF:
 255                         selector = HUB_LED_OFF;
 256                         mode = INDICATOR_AMBER_BLINK;
 257                         break;
 258                 /* blink green/amber = reserved */
 259                 case INDICATOR_ALT_BLINK:
 260                         selector = HUB_LED_GREEN;
 261                         mode = INDICATOR_ALT_BLINK_OFF;
 262                         break;
 263                 case INDICATOR_ALT_BLINK_OFF:
 264                         selector = HUB_LED_AMBER;
 265                         mode = INDICATOR_ALT_BLINK;
 266                         break;
 267                 default:
 268                         continue;
 269                 }
 270                 if (selector != HUB_LED_AUTO)
 271                         changed = 1;
 272                 set_port_led(hub, i + 1, selector);
 273                 hub->indicator[i] = mode;
 274         }
 275         if (!changed && blinkenlights) {
 276                 cursor++;
 277                 cursor %= hub->descriptor->bNbrPorts;
 278                 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
 279                 hub->indicator[cursor] = INDICATOR_CYCLE;
 280                 changed++;
 281         }
 282         if (changed)
 283                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 284 }
 285
 286 /* use a short timeout for hub/port status fetches */
 287 #define USB_STS_TIMEOUT         1000
 288 #define USB_STS_RETRIES         5
 289
 290 /*
 291  * USB 2.0 spec Section 11.24.2.6
 292  */
 293 static int get_hub_status(struct usb_device *hdev,
 294                 struct usb_hub_status *data)
 295 {
 296         int i, status = -ETIMEDOUT;
 297
 298         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
 299                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 300                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
 301                         data, sizeof(*data), USB_STS_TIMEOUT);
 302         }
 303         return status;
 304 }
 305
 306 /*
 307  * USB 2.0 spec Section 11.24.2.7
 308  */
 309 static int get_port_status(struct usb_device *hdev, int port1,
 310                 struct usb_port_status *data)
 311 {
 312         int i, status = -ETIMEDOUT;
 313
 314         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
 315                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 316                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
 317                         data, sizeof(*data), USB_STS_TIMEOUT);
 318         }
 319         return status;
 320 }
 321
 322 static void kick_khubd(struct usb_hub *hub)
 323 {
 324         unsigned long   flags;
 325
 326         /* Suppress autosuspend until khubd runs */
 327         to_usb_interface(hub->intfdev)->pm_usage_cnt = 1;
 328
 329         spin_lock_irqsave(&hub_event_lock, flags);
 330         if (list_empty(&hub->event_list)) {
 331                 list_add_tail(&hub->event_list, &hub_event_list);
 332                 wake_up(&khubd_wait);
 333         }
 334         spin_unlock_irqrestore(&hub_event_lock, flags);
 335 }
 336
 337 void usb_kick_khubd(struct usb_device *hdev)
 338 {
 339         kick_khubd(hdev_to_hub(hdev));
 340 }
 341
 342
 343 /* completion function, fires on port status changes and various faults */
 344 static void hub_irq(struct urb *urb)
 345 {
 346         struct usb_hub *hub = urb->context;
 347         int status;
 348         int i;
 349         unsigned long bits;
 350
 351         switch (urb->status) {
 352         case -ENOENT:           /* synchronous unlink */
 353         case -ECONNRESET:       /* async unlink */
 354         case -ESHUTDOWN:        /* hardware going away */
 355                 return;
 356
 357         default:                /* presumably an error */
 358                 /* Cause a hub reset after 10 consecutive errors */
 359                 dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
 360                 if ((++hub->nerrors < 10) || hub->error)
 361                         goto resubmit;
 362                 hub->error = urb->status;
 363                 /* FALL THROUGH */
 364
 365         /* let khubd handle things */
 366         case 0:                 /* we got data:  port status changed */
 367                 bits = 0;
 368                 for (i = 0; i < urb->actual_length; ++i)
 369                         bits |= ((unsigned long) ((*hub->buffer)[i]))
 370                                         << (i*8);
 371                 hub->event_bits[0] = bits;
 372                 break;
 373         }
 374
 375         hub->nerrors = 0;
 376
 377         /* Something happened, let khubd figure it out */
 378         kick_khubd(hub);
 379
 380 resubmit:
 381         if (hub->quiescing)
 382                 return;
 383
 384         if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
 385                         && status != -ENODEV && status != -EPERM)
 386                 dev_err (hub->intfdev, "resubmit --> %d\n", status);
 387 }
 388
 389 /* USB 2.0 spec Section 11.24.2.3 */
 390 static inline int
 391 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
 392 {
 393         return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 394                                HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
 395                                tt, NULL, 0, 1000);
 396 }
 397
 398 /*
 399  * enumeration blocks khubd for a long time. we use keventd instead, since
 400  * long blocking there is the exception, not the rule.  accordingly, HCDs
 401  * talking to TTs must queue control transfers (not just bulk and iso), so
 402  * both can talk to the same hub concurrently.
 403  */
 404 static void hub_tt_kevent (struct work_struct *work)
 405 {
 406         struct usb_hub          *hub =
 407                 container_of(work, struct usb_hub, tt.kevent);
 408         unsigned long           flags;
 409
 410         spin_lock_irqsave (&hub->tt.lock, flags);
 411         while (!list_empty (&hub->tt.clear_list)) {
 412                 struct list_head        *temp;
 413                 struct usb_tt_clear     *clear;
 414                 struct usb_device       *hdev = hub->hdev;
 415                 int                     status;
 416
 417                 temp = hub->tt.clear_list.next;
 418                 clear = list_entry (temp, struct usb_tt_clear, clear_list);
 419                 list_del (&clear->clear_list);
 420
 421                 /* drop lock so HCD can concurrently report other TT errors */
 422                 spin_unlock_irqrestore (&hub->tt.lock, flags);
 423                 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
 424                 spin_lock_irqsave (&hub->tt.lock, flags);
 425
 426                 if (status)
 427                         dev_err (&hdev->dev,
 428                                 "clear tt %d (%04x) error %d\n",
 429                                 clear->tt, clear->devinfo, status);
 430                 kfree(clear);
 431         }
 432         spin_unlock_irqrestore (&hub->tt.lock, flags);
 433 }
 434
 435 /**
 436  * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
 437  * @udev: the device whose split transaction failed
 438  * @pipe: identifies the endpoint of the failed transaction
 439  *
 440  * High speed HCDs use this to tell the hub driver that some split control or
 441  * bulk transaction failed in a way that requires clearing internal state of
 442  * a transaction translator.  This is normally detected (and reported) from
 443  * interrupt context.
 444  *
 445  * It may not be possible for that hub to handle additional full (or low)
 446  * speed transactions until that state is fully cleared out.
 447  */
 448 void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
 449 {
 450         struct usb_tt           *tt = udev->tt;
 451         unsigned long           flags;
 452         struct usb_tt_clear     *clear;
 453
 454         /* we've got to cope with an arbitrary number of pending TT clears,
 455          * since each TT has "at least two" buffers that can need it (and
 456          * there can be many TTs per hub).  even if they're uncommon.
 457          */
 458         if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) {
 459                 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
 460                 /* FIXME recover somehow ... RESET_TT? */
 461                 return;
 462         }
 463
 464         /* info that CLEAR_TT_BUFFER needs */
 465         clear->tt = tt->multi ? udev->ttport : 1;
 466         clear->devinfo = usb_pipeendpoint (pipe);
 467         clear->devinfo |= udev->devnum << 4;
 468         clear->devinfo |= usb_pipecontrol (pipe)
 469                         ? (USB_ENDPOINT_XFER_CONTROL << 11)
 470                         : (USB_ENDPOINT_XFER_BULK << 11);
 471         if (usb_pipein (pipe))
 472                 clear->devinfo |= 1 << 15;
 473
 474         /* tell keventd to clear state for this TT */
 475         spin_lock_irqsave (&tt->lock, flags);
 476         list_add_tail (&clear->clear_list, &tt->clear_list);
 477         schedule_work (&tt->kevent);
 478         spin_unlock_irqrestore (&tt->lock, flags);
 479 }
 480
 481 static void hub_power_on(struct usb_hub *hub)
 482 {
 483         int port1;
 484         unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
 485         u16 wHubCharacteristics =
 486                         le16_to_cpu(hub->descriptor->wHubCharacteristics);
 487
 488         /* Enable power on each port.  Some hubs have reserved values
 489          * of LPSM (> 2) in their descriptors, even though they are
 490          * USB 2.0 hubs.  Some hubs do not implement port-power switching
 491          * but only emulate it.  In all cases, the ports won't work
 492          * unless we send these messages to the hub.
 493          */
 494         if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
 495                 dev_dbg(hub->intfdev, "enabling power on all ports\n");
 496         else
 497                 dev_dbg(hub->intfdev, "trying to enable port power on "
 498                                 "non-switchable hub\n");
 499         for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
 500                 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
 501
 502         /* Wait at least 100 msec for power to become stable */
 503         msleep(max(pgood_delay, (unsigned) 100));
 504 }
 505
 506 static void hub_quiesce(struct usb_hub *hub)
 507 {
 508         /* (nonblocking) khubd and related activity won't re-trigger */
 509         hub->quiescing = 1;
 510         hub->activating = 0;
 511
 512         /* (blocking) stop khubd and related activity */
 513         usb_kill_urb(hub->urb);
 514         if (hub->has_indicators)
 515                 cancel_delayed_work(&hub->leds);
 516         if (hub->has_indicators || hub->tt.hub)
 517                 flush_scheduled_work();
 518 }
 519
 520 static void hub_activate(struct usb_hub *hub)
 521 {
 522         int     status;
 523
 524         hub->quiescing = 0;
 525         hub->activating = 1;
 526
 527         status = usb_submit_urb(hub->urb, GFP_NOIO);
 528         if (status < 0)
 529                 dev_err(hub->intfdev, "activate --> %d\n", status);
 530         if (hub->has_indicators && blinkenlights)
 531                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 532
 533         /* scan all ports ASAP */
 534         kick_khubd(hub);
 535 }
 536
 537 static int hub_hub_status(struct usb_hub *hub,
 538                 u16 *status, u16 *change)
 539 {
 540         int ret;
 541
 542         mutex_lock(&hub->status_mutex);
 543         ret = get_hub_status(hub->hdev, &hub->status->hub);
 544         if (ret < 0)
 545                 dev_err (hub->intfdev,
 546                         "%s failed (err = %d)\n", __FUNCTION__, ret);
 547         else {
 548                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
 549                 *change = le16_to_cpu(hub->status->hub.wHubChange);
 550                 ret = 0;
 551         }
 552         mutex_unlock(&hub->status_mutex);
 553         return ret;
 554 }
 555
 556 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
 557 {
 558         struct usb_device *hdev = hub->hdev;
 559         int ret;
 560
 561         if (hdev->children[port1-1] && set_state) {
 562                 usb_set_device_state(hdev->children[port1-1],
 563                                 USB_STATE_NOTATTACHED);
 564         }
 565         ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
 566         if (ret)
 567                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
 568                         port1, ret);
 569
 570         return ret;
 571 }
 572
 573
 574 /* caller has locked the hub device */
 575 static void hub_pre_reset(struct usb_interface *intf)
 576 {
 577         struct usb_hub *hub = usb_get_intfdata(intf);
 578         struct usb_device *hdev = hub->hdev;
 579         int port1;
 580
 581         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
 582                 if (hdev->children[port1 - 1]) {
 583                         usb_disconnect(&hdev->children[port1 - 1]);
 584                         if (hub->error == 0)
 585                                 hub_port_disable(hub, port1, 0);
 586                 }
 587         }
 588         hub_quiesce(hub);
 589 }
 590
 591 /* caller has locked the hub device */
 592 static void hub_post_reset(struct usb_interface *intf)
 593 {
 594         struct usb_hub *hub = usb_get_intfdata(intf);
 595
 596         hub_activate(hub);
 597         hub_power_on(hub);
 598 }
 599
 600
 601 static int hub_configure(struct usb_hub *hub,
 602         struct usb_endpoint_descriptor *endpoint)
 603 {
 604         struct usb_device *hdev = hub->hdev;
 605         struct device *hub_dev = hub->intfdev;
 606         u16 hubstatus, hubchange;
 607         u16 wHubCharacteristics;
 608         unsigned int pipe;
 609         int maxp, ret;
 610         char *message;
 611
 612         hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
 613                         &hub->buffer_dma);
 614         if (!hub->buffer) {
 615                 message = "can't allocate hub irq buffer";
 616                 ret = -ENOMEM;
 617                 goto fail;
 618         }
 619
 620         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
 621         if (!hub->status) {
 622                 message = "can't kmalloc hub status buffer";
 623                 ret = -ENOMEM;
 624                 goto fail;
 625         }
 626         mutex_init(&hub->status_mutex);
 627
 628         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
 629         if (!hub->descriptor) {
 630                 message = "can't kmalloc hub descriptor";
 631                 ret = -ENOMEM;
 632                 goto fail;
 633         }
 634
 635         /* Request the entire hub descriptor.
 636          * hub->descriptor can handle USB_MAXCHILDREN ports,
 637          * but the hub can/will return fewer bytes here.
 638          */
 639         ret = get_hub_descriptor(hdev, hub->descriptor,
 640                         sizeof(*hub->descriptor));
 641         if (ret < 0) {
 642                 message = "can't read hub descriptor";
 643                 goto fail;
 644         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
 645                 message = "hub has too many ports!";
 646                 ret = -ENODEV;
 647                 goto fail;
 648         }
 649
 650         hdev->maxchild = hub->descriptor->bNbrPorts;
 651         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
 652                 (hdev->maxchild == 1) ? "" : "s");
 653
 654         wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
 655
 656         if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
 657                 int     i;
 658                 char    portstr [USB_MAXCHILDREN + 1];
 659
 660                 for (i = 0; i < hdev->maxchild; i++)
 661                         portstr[i] = hub->descriptor->DeviceRemovable
 662                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
 663                                 ? 'F' : 'R';
 664                 portstr[hdev->maxchild] = 0;
 665                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
 666         } else
 667                 dev_dbg(hub_dev, "standalone hub\n");
 668
 669         switch (wHubCharacteristics & HUB_CHAR_LPSM) {
 670                 case 0x00:
 671                         dev_dbg(hub_dev, "ganged power switching\n");
 672                         break;
 673                 case 0x01:
 674                         dev_dbg(hub_dev, "individual port power switching\n");
 675                         break;
 676                 case 0x02:
 677                 case 0x03:
 678                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
 679                         break;
 680         }
 681
 682         switch (wHubCharacteristics & HUB_CHAR_OCPM) {
 683                 case 0x00:
 684                         dev_dbg(hub_dev, "global over-current protection\n");
 685                         break;
 686                 case 0x08:
 687                         dev_dbg(hub_dev, "individual port over-current protection\n");
 688                         break;
 689                 case 0x10:
 690                 case 0x18:
 691                         dev_dbg(hub_dev, "no over-current protection\n");
 692                         break;
 693         }
 694
 695         spin_lock_init (&hub->tt.lock);
 696         INIT_LIST_HEAD (&hub->tt.clear_list);
 697         INIT_WORK (&hub->tt.kevent, hub_tt_kevent);
 698         switch (hdev->descriptor.bDeviceProtocol) {
 699                 case 0:
 700                         break;
 701                 case 1:
 702                         dev_dbg(hub_dev, "Single TT\n");
 703                         hub->tt.hub = hdev;
 704                         break;
 705                 case 2:
 706                         ret = usb_set_interface(hdev, 0, 1);
 707                         if (ret == 0) {
 708                                 dev_dbg(hub_dev, "TT per port\n");
 709                                 hub->tt.multi = 1;
 710                         } else
 711                                 dev_err(hub_dev, "Using single TT (err %d)\n",
 712                                         ret);
 713                         hub->tt.hub = hdev;
 714                         break;
 715                 default:
 716                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
 717                                 hdev->descriptor.bDeviceProtocol);
 718                         break;
 719         }
 720
 721         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
 722         switch (wHubCharacteristics & HUB_CHAR_TTTT) {
 723                 case HUB_TTTT_8_BITS:
 724                         if (hdev->descriptor.bDeviceProtocol != 0) {
 725                                 hub->tt.think_time = 666;
 726                                 dev_dbg(hub_dev, "TT requires at most %d "
 727                                                 "FS bit times (%d ns)\n",
 728                                         8, hub->tt.think_time);
 729                         }
 730                         break;
 731                 case HUB_TTTT_16_BITS:
 732                         hub->tt.think_time = 666 * 2;
 733                         dev_dbg(hub_dev, "TT requires at most %d "
 734                                         "FS bit times (%d ns)\n",
 735                                 16, hub->tt.think_time);
 736                         break;
 737                 case HUB_TTTT_24_BITS:
 738                         hub->tt.think_time = 666 * 3;
 739                         dev_dbg(hub_dev, "TT requires at most %d "
 740                                         "FS bit times (%d ns)\n",
 741                                 24, hub->tt.think_time);
 742                         break;
 743                 case HUB_TTTT_32_BITS:
 744                         hub->tt.think_time = 666 * 4;
 745                         dev_dbg(hub_dev, "TT requires at most %d "
 746                                         "FS bit times (%d ns)\n",
 747                                 32, hub->tt.think_time);
 748                         break;
 749         }
 750
 751         /* probe() zeroes hub->indicator[] */
 752         if (wHubCharacteristics & HUB_CHAR_PORTIND) {
 753                 hub->has_indicators = 1;
 754                 dev_dbg(hub_dev, "Port indicators are supported\n");
 755         }
 756
 757         dev_dbg(hub_dev, "power on to power good time: %dms\n",
 758                 hub->descriptor->bPwrOn2PwrGood * 2);
 759
 760         /* power budgeting mostly matters with bus-powered hubs,
 761          * and battery-powered root hubs (may provide just 8 mA).
 762          */
 763         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
 764         if (ret < 2) {
 765                 message = "can't get hub status";
 766                 goto fail;
 767         }
 768         le16_to_cpus(&hubstatus);
 769         if (hdev == hdev->bus->root_hub) {
 770                 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
 771                         hub->mA_per_port = 500;
 772                 else {
 773                         hub->mA_per_port = hdev->bus_mA;
 774                         hub->limited_power = 1;
 775                 }
 776         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
 777                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
 778                         hub->descriptor->bHubContrCurrent);
 779                 hub->limited_power = 1;
 780                 if (hdev->maxchild > 0) {
 781                         int remaining = hdev->bus_mA -
 782                                         hub->descriptor->bHubContrCurrent;
 783
 784                         if (remaining < hdev->maxchild * 100)
 785                                 dev_warn(hub_dev,
 786                                         "insufficient power available "
 787                                         "to use all downstream ports\n");
 788                         hub->mA_per_port = 100;         /* 7.2.1.1 */
 789                 }
 790         } else {        /* Self-powered external hub */
 791                 /* FIXME: What about battery-powered external hubs that
 792                  * provide less current per port? */
 793                 hub->mA_per_port = 500;
 794         }
 795         if (hub->mA_per_port < 500)
 796                 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
 797                                 hub->mA_per_port);
 798
 799         ret = hub_hub_status(hub, &hubstatus, &hubchange);
 800         if (ret < 0) {
 801                 message = "can't get hub status";
 802                 goto fail;
 803         }
 804
 805         /* local power status reports aren't always correct */
 806         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
 807                 dev_dbg(hub_dev, "local power source is %s\n",
 808                         (hubstatus & HUB_STATUS_LOCAL_POWER)
 809                         ? "lost (inactive)" : "good");
 810
 811         if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
 812                 dev_dbg(hub_dev, "%sover-current condition exists\n",
 813                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
 814
 815         /* set up the interrupt endpoint
 816          * We use the EP's maxpacket size instead of (PORTS+1+7)/8
 817          * bytes as USB2.0[11.12.3] says because some hubs are known
 818          * to send more data (and thus cause overflow). For root hubs,
 819          * maxpktsize is defined in hcd.c's fake endpoint descriptors
 820          * to be big enough for at least USB_MAXCHILDREN ports. */
 821         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
 822         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
 823
 824         if (maxp > sizeof(*hub->buffer))
 825                 maxp = sizeof(*hub->buffer);
 826
 827         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
 828         if (!hub->urb) {
 829                 message = "couldn't allocate interrupt urb";
 830                 ret = -ENOMEM;
 831                 goto fail;
 832         }
 833
 834         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
 835                 hub, endpoint->bInterval);
 836         hub->urb->transfer_dma = hub->buffer_dma;
 837         hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 838
 839         /* maybe cycle the hub leds */
 840         if (hub->has_indicators && blinkenlights)
 841                 hub->indicator [0] = INDICATOR_CYCLE;
 842
 843         hub_power_on(hub);
 844         hub_activate(hub);
 845         return 0;
 846
 847 fail:
 848         dev_err (hub_dev, "config failed, %s (err %d)\n",
 849                         message, ret);
 850         /* hub_disconnect() frees urb and descriptor */
 851         return ret;
 852 }
 853
 854 static unsigned highspeed_hubs;
 855
 856 static void hub_disconnect(struct usb_interface *intf)
 857 {
 858         struct usb_hub *hub = usb_get_intfdata (intf);
 859         struct usb_device *hdev;
 860
 861         /* Disconnect all children and quiesce the hub */
 862         hub->error = 0;
 863         hub_pre_reset(intf);
 864
 865         usb_set_intfdata (intf, NULL);
 866         hdev = hub->hdev;
 867
 868         if (hdev->speed == USB_SPEED_HIGH)
 869                 highspeed_hubs--;
 870
 871         usb_free_urb(hub->urb);
 872         hub->urb = NULL;
 873
 874         spin_lock_irq(&hub_event_lock);
 875         list_del_init(&hub->event_list);
 876         spin_unlock_irq(&hub_event_lock);
 877
 878         kfree(hub->descriptor);
 879         hub->descriptor = NULL;
 880
 881         kfree(hub->status);
 882         hub->status = NULL;
 883
 884         if (hub->buffer) {
 885                 usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
 886                                 hub->buffer_dma);
 887                 hub->buffer = NULL;
 888         }
 889
 890         kfree(hub);
 891 }
 892
 893 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
 894 {
 895         struct usb_host_interface *desc;
 896         struct usb_endpoint_descriptor *endpoint;
 897         struct usb_device *hdev;
 898         struct usb_hub *hub;
 899
 900         desc = intf->cur_altsetting;
 901         hdev = interface_to_usbdev(intf);
 902
 903 #ifdef  CONFIG_USB_OTG_BLACKLIST_HUB
 904         if (hdev->parent) {
 905                 dev_warn(&intf->dev, "ignoring external hub\n");
 906                 return -ENODEV;
 907         }
 908 #endif
 909
 910         /* Some hubs have a subclass of 1, which AFAICT according to the */
 911         /*  specs is not defined, but it works */
 912         if ((desc->desc.bInterfaceSubClass != 0) &&
 913             (desc->desc.bInterfaceSubClass != 1)) {
 914 descriptor_error:
 915                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
 916                 return -EIO;
 917         }
 918
 919         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
 920         if (desc->desc.bNumEndpoints != 1)
 921                 goto descriptor_error;
 922
 923         endpoint = &desc->endpoint[0].desc;
 924
 925         /* If it's not an interrupt in endpoint, we'd better punt! */
 926         if (!usb_endpoint_is_int_in(endpoint))
 927                 goto descriptor_error;
 928
 929         /* We found a hub */
 930         dev_info (&intf->dev, "USB hub found\n");
 931
 932         hub = kzalloc(sizeof(*hub), GFP_KERNEL);
 933         if (!hub) {
 934                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
 935                 return -ENOMEM;
 936         }
 937
 938         INIT_LIST_HEAD(&hub->event_list);
 939         hub->intfdev = &intf->dev;
 940         hub->hdev = hdev;
 941         INIT_DELAYED_WORK(&hub->leds, led_work);
 942
 943         usb_set_intfdata (intf, hub);
 944         intf->needs_remote_wakeup = 1;
 945
 946         if (hdev->speed == USB_SPEED_HIGH)
 947                 highspeed_hubs++;
 948
 949         if (hub_configure(hub, endpoint) >= 0)
 950                 return 0;
 951
 952         hub_disconnect (intf);
 953         return -ENODEV;
 954 }
 955
 956 static int
 957 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
 958 {
 959         struct usb_device *hdev = interface_to_usbdev (intf);
 960
 961         /* assert ifno == 0 (part of hub spec) */
 962         switch (code) {
 963         case USBDEVFS_HUB_PORTINFO: {
 964                 struct usbdevfs_hub_portinfo *info = user_data;
 965                 int i;
 966
 967                 spin_lock_irq(&device_state_lock);
 968                 if (hdev->devnum <= 0)
 969                         info->nports = 0;
 970                 else {
 971                         info->nports = hdev->maxchild;
 972                         for (i = 0; i < info->nports; i++) {
 973                                 if (hdev->children[i] == NULL)
 974                                         info->port[i] = 0;
 975                                 else
 976                                         info->port[i] =
 977                                                 hdev->children[i]->devnum;
 978                         }
 979                 }
 980                 spin_unlock_irq(&device_state_lock);
 981
 982                 return info->nports + 1;
 983                 }
 984
 985         default:
 986                 return -ENOSYS;
 987         }
 988 }
 989
 990
 991 /* grab device/port lock, returning index of that port (zero based).
 992  * protects the upstream link used by this device from concurrent
 993  * tree operations like suspend, resume, reset, and disconnect, which
 994  * apply to everything downstream of a given port.
 995  */
 996 static int locktree(struct usb_device *udev)
 997 {
 998         int                     t;
 999         struct usb_device       *hdev;
1000
1001         if (!udev)
1002                 return -ENODEV;
1003
1004         /* root hub is always the first lock in the series */
1005         hdev = udev->parent;
1006         if (!hdev) {
1007                 usb_lock_device(udev);
1008                 return 0;
1009         }
1010
1011         /* on the path from root to us, lock everything from
1012          * top down, dropping parent locks when not needed
1013          */
1014         t = locktree(hdev);
1015         if (t < 0)
1016                 return t;
1017
1018         /* everything is fail-fast once disconnect
1019          * processing starts
1020          */
1021         if (udev->state == USB_STATE_NOTATTACHED) {
1022                 usb_unlock_device(hdev);
1023                 return -ENODEV;
1024         }
1025
1026         /* when everyone grabs locks top->bottom,
1027          * non-overlapping work may be concurrent
1028          */
1029         usb_lock_device(udev);
1030         usb_unlock_device(hdev);
1031         return udev->portnum;
1032 }
1033
1034 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1035 {
1036         int i;
1037
1038         for (i = 0; i < udev->maxchild; ++i) {
1039                 if (udev->children[i])
1040                         recursively_mark_NOTATTACHED(udev->children[i]);
1041         }
1042         if (udev->state == USB_STATE_SUSPENDED)
1043                 udev->discon_suspended = 1;
1044         udev->state = USB_STATE_NOTATTACHED;
1045 }
1046
1047 /**
1048  * usb_set_device_state - change a device's current state (usbcore, hcds)
1049  * @udev: pointer to device whose state should be changed
1050  * @new_state: new state value to be stored
1051  *
1052  * udev->state is _not_ fully protected by the device lock.  Although
1053  * most transitions are made only while holding the lock, the state can
1054  * can change to USB_STATE_NOTATTACHED at almost any time.  This
1055  * is so that devices can be marked as disconnected as soon as possible,
1056  * without having to wait for any semaphores to be released.  As a result,
1057  * all changes to any device's state must be protected by the
1058  * device_state_lock spinlock.
1059  *
1060  * Once a device has been added to the device tree, all changes to its state
1061  * should be made using this routine.  The state should _not_ be set directly.
1062  *
1063  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1064  * Otherwise udev->state is set to new_state, and if new_state is
1065  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1066  * to USB_STATE_NOTATTACHED.
1067  */
1068 void usb_set_device_state(struct usb_device *udev,
1069                 enum usb_device_state new_state)
1070 {
1071         unsigned long flags;
1072
1073         spin_lock_irqsave(&device_state_lock, flags);
1074         if (udev->state == USB_STATE_NOTATTACHED)
1075                 ;       /* do nothing */
1076         else if (new_state != USB_STATE_NOTATTACHED) {
1077
1078                 /* root hub wakeup capabilities are managed out-of-band
1079                  * and may involve silicon errata ... ignore them here.
1080                  */
1081                 if (udev->parent) {
1082                         if (udev->state == USB_STATE_SUSPENDED
1083                                         || new_state == USB_STATE_SUSPENDED)
1084                                 ;       /* No change to wakeup settings */
1085                         else if (new_state == USB_STATE_CONFIGURED)
1086                                 device_init_wakeup(&udev->dev,
1087                                         (udev->actconfig->desc.bmAttributes
1088                                          & USB_CONFIG_ATT_WAKEUP));
1089                         else
1090                                 device_init_wakeup(&udev->dev, 0);
1091                 }
1092                 udev->state = new_state;
1093         } else
1094                 recursively_mark_NOTATTACHED(udev);
1095         spin_unlock_irqrestore(&device_state_lock, flags);
1096 }
1097
1098
1099 #ifdef  CONFIG_PM
1100
1101 /**
1102  * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
1103  * @rhdev: struct usb_device for the root hub
1104  *
1105  * The USB host controller driver calls this function when its root hub
1106  * is resumed and Vbus power has been interrupted or the controller
1107  * has been reset.  The routine marks all the children of the root hub
1108  * as NOTATTACHED and marks logical connect-change events on their ports.
1109  */
1110 void usb_root_hub_lost_power(struct usb_device *rhdev)
1111 {
1112         struct usb_hub *hub;
1113         int port1;
1114         unsigned long flags;
1115
1116         dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
1117
1118         /* Make sure no potential wakeup events get lost,
1119          * by forcing the root hub to be resumed.
1120          */
1121         rhdev->dev.power.prev_state.event = PM_EVENT_ON;
1122
1123         spin_lock_irqsave(&device_state_lock, flags);
1124         hub = hdev_to_hub(rhdev);
1125         for (port1 = 1; port1 <= rhdev->maxchild; ++port1) {
1126                 if (rhdev->children[port1 - 1]) {
1127                         recursively_mark_NOTATTACHED(
1128                                         rhdev->children[port1 - 1]);
1129                         set_bit(port1, hub->change_bits);
1130                 }
1131         }
1132         spin_unlock_irqrestore(&device_state_lock, flags);
1133 }
1134 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
1135
1136 #endif  /* CONFIG_PM */
1137
1138 static void choose_address(struct usb_device *udev)
1139 {
1140         int             devnum;
1141         struct usb_bus  *bus = udev->bus;
1142
1143         /* If khubd ever becomes multithreaded, this will need a lock */
1144
1145         /* Try to allocate the next devnum beginning at bus->devnum_next. */
1146         devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1147                         bus->devnum_next);
1148         if (devnum >= 128)
1149                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1150
1151         bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1152
1153         if (devnum < 128) {
1154                 set_bit(devnum, bus->devmap.devicemap);
1155                 udev->devnum = devnum;
1156         }
1157 }
1158
1159 static void release_address(struct usb_device *udev)
1160 {
1161         if (udev->devnum > 0) {
1162                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1163                 udev->devnum = -1;
1164         }
1165 }
1166
1167 /**
1168  * usb_disconnect - disconnect a device (usbcore-internal)
1169  * @pdev: pointer to device being disconnected
1170  * Context: !in_interrupt ()
1171  *
1172  * Something got disconnected. Get rid of it and all of its children.
1173  *
1174  * If *pdev is a normal device then the parent hub must already be locked.
1175  * If *pdev is a root hub then this routine will acquire the
1176  * usb_bus_list_lock on behalf of the caller.
1177  *
1178  * Only hub drivers (including virtual root hub drivers for host
1179  * controllers) should ever call this.
1180  *
1181  * This call is synchronous, and may not be used in an interrupt context.
1182  */
1183 void usb_disconnect(struct usb_device **pdev)
1184 {
1185         struct usb_device       *udev = *pdev;
1186         int                     i;
1187
1188         if (!udev) {
1189                 pr_debug ("%s nodev\n", __FUNCTION__);
1190                 return;
1191         }
1192
1193         /* mark the device as inactive, so any further urb submissions for
1194          * this device (and any of its children) will fail immediately.
1195          * this quiesces everyting except pending urbs.
1196          */
1197         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1198         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1199
1200         usb_lock_device(udev);
1201
1202         /* Free up all the children before we remove this device */
1203         for (i = 0; i < USB_MAXCHILDREN; i++) {
1204                 if (udev->children[i])
1205                         usb_disconnect(&udev->children[i]);
1206         }
1207
1208         /* deallocate hcd/hardware state ... nuking all pending urbs and
1209          * cleaning up all state associated with the current configuration
1210          * so that the hardware is now fully quiesced.
1211          */
1212         dev_dbg (&udev->dev, "unregistering device\n");
1213         usb_disable_device(udev, 0);
1214
1215         usb_unlock_device(udev);
1216
1217         /* Unregister the device.  The device driver is responsible
1218          * for removing the device files from usbfs and sysfs and for
1219          * de-configuring the device.
1220          */
1221         device_del(&udev->dev);
1222
1223         /* Free the device number and delete the parent's children[]
1224          * (or root_hub) pointer.
1225          */
1226         release_address(udev);
1227
1228         /* Avoid races with recursively_mark_NOTATTACHED() */
1229         spin_lock_irq(&device_state_lock);
1230         *pdev = NULL;
1231         spin_unlock_irq(&device_state_lock);
1232
1233         /* Decrement the parent's count of unsuspended children */
1234         if (udev->parent) {
1235                 usb_pm_lock(udev);
1236                 if (!udev->discon_suspended)
1237                         usb_autosuspend_device(udev->parent);
1238                 usb_pm_unlock(udev);
1239         }
1240
1241         put_device(&udev->dev);
1242 }
1243
1244 #ifdef DEBUG
1245 static void show_string(struct usb_device *udev, char *id, char *string)
1246 {
1247         if (!string)
1248                 return;
1249         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1250 }
1251
1252 #else
1253 static inline void show_string(struct usb_device *udev, char *id, char *string)
1254 {}
1255 #endif
1256
1257
1258 #ifdef  CONFIG_USB_OTG
1259 #include "otg_whitelist.h"
1260 static int __usb_port_suspend(struct usb_device *, int port1);
1261 #endif
1262
1263 static int __usb_new_device(void *void_data)
1264 {
1265         struct usb_device *udev = void_data;
1266         int err;
1267
1268         /* Lock ourself into memory in order to keep a probe sequence
1269          * sleeping in a new thread from allowing us to be unloaded.
1270          */
1271         if (!try_module_get(THIS_MODULE))
1272                 return -EINVAL;
1273
1274         err = usb_get_configuration(udev);
1275         if (err < 0) {
1276                 dev_err(&udev->dev, "can't read configurations, error %d\n",
1277                         err);
1278                 goto fail;
1279         }
1280
1281         /* read the standard strings and cache them if present */
1282         udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1283         udev->manufacturer = usb_cache_string(udev,
1284                         udev->descriptor.iManufacturer);
1285         udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1286
1287         /* Tell the world! */
1288         dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1289                         "SerialNumber=%d\n",
1290                         udev->descriptor.iManufacturer,
1291                         udev->descriptor.iProduct,
1292                         udev->descriptor.iSerialNumber);
1293         show_string(udev, "Product", udev->product);
1294         show_string(udev, "Manufacturer", udev->manufacturer);
1295         show_string(udev, "SerialNumber", udev->serial);
1296
1297 #ifdef  CONFIG_USB_OTG
1298         /*
1299          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1300          * to wake us after we've powered off VBUS; and HNP, switching roles
1301          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1302          */
1303         if (!udev->bus->is_b_host
1304                         && udev->config
1305                         && udev->parent == udev->bus->root_hub) {
1306                 struct usb_otg_descriptor       *desc = 0;
1307                 struct usb_bus                  *bus = udev->bus;
1308
1309                 /* descriptor may appear anywhere in config */
1310                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1311                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1312                                         USB_DT_OTG, (void **) &desc) == 0) {
1313                         if (desc->bmAttributes & USB_OTG_HNP) {
1314                                 unsigned                port1 = udev->portnum;
1315
1316                                 dev_info(&udev->dev,
1317                                         "Dual-Role OTG device on %sHNP port\n",
1318                                         (port1 == bus->otg_port)
1319                                                 ? "" : "non-");
1320
1321                                 /* enable HNP before suspend, it's simpler */
1322                                 if (port1 == bus->otg_port)
1323                                         bus->b_hnp_enable = 1;
1324                                 err = usb_control_msg(udev,
1325                                         usb_sndctrlpipe(udev, 0),
1326                                         USB_REQ_SET_FEATURE, 0,
1327                                         bus->b_hnp_enable
1328                                                 ? USB_DEVICE_B_HNP_ENABLE
1329                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1330                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1331                                 if (err < 0) {
1332                                         /* OTG MESSAGE: report errors here,
1333                                          * customize to match your product.
1334                                          */
1335                                         dev_info(&udev->dev,
1336                                                 "can't set HNP mode; %d\n",
1337                                                 err);
1338                                         bus->b_hnp_enable = 0;
1339                                 }
1340                         }
1341                 }
1342         }
1343
1344         if (!is_targeted(udev)) {
1345
1346                 /* Maybe it can talk to us, though we can't talk to it.
1347                  * (Includes HNP test device.)
1348                  */
1349                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1350                         err = __usb_port_suspend(udev, udev->bus->otg_port);
1351                         if (err < 0)
1352                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1353                 }
1354                 err = -ENODEV;
1355                 goto fail;
1356         }
1357 #endif
1358
1359         /* Register the device.  The device driver is responsible
1360          * for adding the device files to usbfs and sysfs and for
1361          * configuring the device.
1362          */
1363         err = device_add (&udev->dev);
1364         if (err) {
1365                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1366                 goto fail;
1367         }
1368
1369         /* Increment the parent's count of unsuspended children */
1370         if (udev->parent)
1371                 usb_autoresume_device(udev->parent);
1372
1373 exit:
1374         module_put(THIS_MODULE);
1375         return err;
1376
1377 fail:
1378         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1379         goto exit;
1380 }
1381
1382 /**
1383  * usb_new_device - perform initial device setup (usbcore-internal)
1384  * @udev: newly addressed device (in ADDRESS state)
1385  *
1386  * This is called with devices which have been enumerated, but not yet
1387  * configured.  The device descriptor is available, but not descriptors
1388  * for any device configuration.  The caller must have locked either
1389  * the parent hub (if udev is a normal device) or else the
1390  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1391  * udev has already been installed, but udev is not yet visible through
1392  * sysfs or other filesystem code.
1393  *
1394  * The return value for this function depends on if the
1395  * multithread_probe variable is set or not.  If it's set, it will
1396  * return a if the probe thread was successfully created or not.  If the
1397  * variable is not set, it will return if the device is configured
1398  * properly or not.  interfaces, in sysfs); else a negative errno value.
1399  *
1400  * This call is synchronous, and may not be used in an interrupt context.
1401  *
1402  * Only the hub driver or root-hub registrar should ever call this.
1403  */
1404 int usb_new_device(struct usb_device *udev)
1405 {
1406         struct task_struct *probe_task;
1407         int ret = 0;
1408
1409         if (multithread_probe) {
1410                 probe_task = kthread_run(__usb_new_device, udev,
1411                                          "usb-probe-%s", udev->devnum);
1412                 if (IS_ERR(probe_task))
1413                         ret = PTR_ERR(probe_task);
1414         } else
1415                 ret = __usb_new_device(udev);
1416
1417         return ret;
1418 }
1419
1420 static int hub_port_status(struct usb_hub *hub, int port1,
1421                                u16 *status, u16 *change)
1422 {
1423         int ret;
1424
1425         mutex_lock(&hub->status_mutex);
1426         ret = get_port_status(hub->hdev, port1, &hub->status->port);
1427         if (ret < 4) {
1428                 dev_err (hub->intfdev,
1429                         "%s failed (err = %d)\n", __FUNCTION__, ret);
1430                 if (ret >= 0)
1431                         ret = -EIO;
1432         } else {
1433                 *status = le16_to_cpu(hub->status->port.wPortStatus);
1434                 *change = le16_to_cpu(hub->status->port.wPortChange);
1435                 ret = 0;
1436         }
1437         mutex_unlock(&hub->status_mutex);
1438         return ret;
1439 }
1440
1441
1442 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
1443 static unsigned hub_is_wusb(struct usb_hub *hub)
1444 {
1445         struct usb_hcd *hcd;
1446         if (hub->hdev->parent != NULL)  /* not a root hub? */
1447                 return 0;
1448         hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
1449         return hcd->wireless;
1450 }
1451
1452
1453 #define PORT_RESET_TRIES        5
1454 #define SET_ADDRESS_TRIES       2
1455 #define GET_DESCRIPTOR_TRIES    2
1456 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1457 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1458
1459 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1460 #define HUB_SHORT_RESET_TIME    10
1461 #define HUB_LONG_RESET_TIME     200
1462 #define HUB_RESET_TIMEOUT       500
1463
1464 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1465                                 struct usb_device *udev, unsigned int delay)
1466 {
1467         int delay_time, ret;
1468         u16 portstatus;
1469         u16 portchange;
1470
1471         for (delay_time = 0;
1472                         delay_time < HUB_RESET_TIMEOUT;
1473                         delay_time += delay) {
1474                 /* wait to give the device a chance to reset */
1475                 msleep(delay);
1476
1477                 /* read and decode port status */
1478                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1479                 if (ret < 0)
1480                         return ret;
1481
1482                 /* Device went away? */
1483                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1484                         return -ENOTCONN;
1485
1486                 /* bomb out completely if something weird happened */
1487                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1488                         return -EINVAL;
1489
1490                 /* if we`ve finished resetting, then break out of the loop */
1491                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1492                     (portstatus & USB_PORT_STAT_ENABLE)) {
1493                         if (hub_is_wusb(hub))
1494                                 udev->speed = USB_SPEED_VARIABLE;
1495                         else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1496                                 udev->speed = USB_SPEED_HIGH;
1497                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1498                                 udev->speed = USB_SPEED_LOW;
1499                         else
1500                                 udev->speed = USB_SPEED_FULL;
1501                         return 0;
1502                 }
1503
1504                 /* switch to the long delay after two short delay failures */
1505                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1506                         delay = HUB_LONG_RESET_TIME;
1507
1508                 dev_dbg (hub->intfdev,
1509                         "port %d not reset yet, waiting %dms\n",
1510                         port1, delay);
1511         }
1512
1513         return -EBUSY;
1514 }
1515
1516 static int hub_port_reset(struct usb_hub *hub, int port1,
1517                                 struct usb_device *udev, unsigned int delay)
1518 {
1519         int i, status;
1520
1521         /* Reset the port */
1522         for (i = 0; i < PORT_RESET_TRIES; i++) {
1523                 status = set_port_feature(hub->hdev,
1524                                 port1, USB_PORT_FEAT_RESET);
1525                 if (status)
1526                         dev_err(hub->intfdev,
1527                                         "cannot reset port %d (err = %d)\n",
1528                                         port1, status);
1529                 else {
1530                         status = hub_port_wait_reset(hub, port1, udev, delay);
1531                         if (status && status != -ENOTCONN)
1532                                 dev_dbg(hub->intfdev,
1533                                                 "port_wait_reset: err = %d\n",
1534                                                 status);
1535                 }
1536
1537                 /* return on disconnect or reset */
1538                 switch (status) {
1539                 case 0:
1540                         /* TRSTRCY = 10 ms; plus some extra */
1541                         msleep(10 + 40);
1542                         /* FALL THROUGH */
1543                 case -ENOTCONN:
1544                 case -ENODEV:
1545                         clear_port_feature(hub->hdev,
1546                                 port1, USB_PORT_FEAT_C_RESET);
1547                         /* FIXME need disconnect() for NOTATTACHED device */
1548                         usb_set_device_state(udev, status
1549                                         ? USB_STATE_NOTATTACHED
1550                                         : USB_STATE_DEFAULT);
1551                         return status;
1552                 }
1553
1554                 dev_dbg (hub->intfdev,
1555                         "port %d not enabled, trying reset again...\n",
1556                         port1);
1557                 delay = HUB_LONG_RESET_TIME;
1558         }
1559
1560         dev_err (hub->intfdev,
1561                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1562                 port1);
1563
1564         return status;
1565 }
1566
1567 /*
1568  * Disable a port and mark a logical connnect-change event, so that some
1569  * time later khubd will disconnect() any existing usb_device on the port
1570  * and will re-enumerate if there actually is a device attached.
1571  */
1572 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1573 {
1574         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1575         hub_port_disable(hub, port1, 1);
1576
1577         /* FIXME let caller ask to power down the port:
1578          *  - some devices won't enumerate without a VBUS power cycle
1579          *  - SRP saves power that way
1580          *  - ... new call, TBD ...
1581          * That's easy if this hub can switch power per-port, and
1582          * khubd reactivates the port later (timer, SRP, etc).
1583          * Powerdown must be optional, because of reset/DFU.
1584          */
1585
1586         set_bit(port1, hub->change_bits);
1587         kick_khubd(hub);
1588 }
1589
1590 #ifdef  CONFIG_PM
1591
1592 #ifdef  CONFIG_USB_SUSPEND
1593
1594 /*
1595  * Selective port suspend reduces power; most suspended devices draw
1596  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1597  * All devices below the suspended port are also suspended.
1598  *
1599  * Devices leave suspend state when the host wakes them up.  Some devices
1600  * also support "remote wakeup", where the device can activate the USB
1601  * tree above them to deliver data, such as a keypress or packet.  In
1602  * some cases, this wakes the USB host.
1603  */
1604 static int hub_port_suspend(struct usb_hub *hub, int port1,
1605                 struct usb_device *udev)
1606 {
1607         int     status;
1608
1609         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1610
1611         /* enable remote wakeup when appropriate; this lets the device
1612          * wake up the upstream hub (including maybe the root hub).
1613          *
1614          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1615          * we don't explicitly enable it here.
1616          */
1617         if (udev->do_remote_wakeup) {
1618                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1619                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1620                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1621                                 NULL, 0,
1622                                 USB_CTRL_SET_TIMEOUT);
1623                 if (status)
1624                         dev_dbg(&udev->dev,
1625                                 "won't remote wakeup, status %d\n",
1626                                 status);
1627         }
1628
1629         /* see 7.1.7.6 */
1630         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1631         if (status) {
1632                 dev_dbg(hub->intfdev,
1633                         "can't suspend port %d, status %d\n",
1634                         port1, status);
1635                 /* paranoia:  "should not happen" */
1636                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1637                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1638                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1639                                 NULL, 0,
1640                                 USB_CTRL_SET_TIMEOUT);
1641         } else {
1642                 /* device has up to 10 msec to fully suspend */
1643                 dev_dbg(&udev->dev, "usb %ssuspend\n",
1644                                 udev->auto_pm ? "auto-" : "");
1645                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1646                 msleep(10);
1647         }
1648         return status;
1649 }
1650
1651 /*
1652  * Devices on USB hub ports have only one "suspend" state, corresponding
1653  * to ACPI D2, "may cause the device to lose some context".
1654  * State transitions include:
1655  *
1656  *   - suspend, resume ... when the VBUS power link stays live
1657  *   - suspend, disconnect ... VBUS lost
1658  *
1659  * Once VBUS drop breaks the circuit, the port it's using has to go through
1660  * normal re-enumeration procedures, starting with enabling VBUS power.
1661  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1662  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1663  * timer, no SRP, no requests through sysfs.
1664  *
1665  * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1666  * the root hub for their bus goes into global suspend ... so we don't
1667  * (falsely) update the device power state to say it suspended.
1668  */
1669 static int __usb_port_suspend (struct usb_device *udev, int port1)
1670 {
1671         int     status = 0;
1672
1673         /* caller owns the udev device lock */
1674         if (port1 < 0)
1675                 return port1;
1676
1677         /* we change the device's upstream USB link,
1678          * but root hubs have no upstream USB link.
1679          */
1680         if (udev->parent)
1681                 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1682                                 udev);
1683         else {
1684                 dev_dbg(&udev->dev, "usb %ssuspend\n",
1685                                 udev->auto_pm ? "auto-" : "");
1686                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1687         }
1688         return status;
1689 }
1690
1691 /*
1692  * usb_port_suspend - suspend a usb device's upstream port
1693  * @udev: device that's no longer in active use
1694  * Context: must be able to sleep; device not locked; pm locks held
1695  *
1696  * Suspends a USB device that isn't in active use, conserving power.
1697  * Devices may wake out of a suspend, if anything important happens,
1698  * using the remote wakeup mechanism.  They may also be taken out of
1699  * suspend by the host, using usb_port_resume().  It's also routine
1700  * to disconnect devices while they are suspended.
1701  *
1702  * This only affects the USB hardware for a device; its interfaces
1703  * (and, for hubs, child devices) must already have been suspended.
1704  *
1705  * Suspending OTG devices may trigger HNP, if that's been enabled
1706  * between a pair of dual-role devices.  That will change roles, such
1707  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1708  *
1709  * Returns 0 on success, else negative errno.
1710  */
1711 int usb_port_suspend(struct usb_device *udev)
1712 {
1713         return __usb_port_suspend(udev, udev->portnum);
1714 }
1715
1716 /*
1717  * If the USB "suspend" state is in use (rather than "global suspend"),
1718  * many devices will be individually taken out of suspend state using
1719  * special" resume" signaling.  These routines kick in shortly after
1720  * hardware resume signaling is finished, either because of selective
1721  * resume (by host) or remote wakeup (by device) ... now see what changed
1722  * in the tree that's rooted at this device.
1723  */
1724 static int finish_port_resume(struct usb_device *udev)
1725 {
1726         int     status;
1727         u16     devstatus;
1728
1729         /* caller owns the udev device lock */
1730         dev_dbg(&udev->dev, "finish resume\n");
1731
1732         /* usb ch9 identifies four variants of SUSPENDED, based on what
1733          * state the device resumes to.  Linux currently won't see the
1734          * first two on the host side; they'd be inside hub_port_init()
1735          * during many timeouts, but khubd can't suspend until later.
1736          */
1737         usb_set_device_state(udev, udev->actconfig
1738                         ? USB_STATE_CONFIGURED
1739                         : USB_STATE_ADDRESS);
1740
1741         /* 10.5.4.5 says be sure devices in the tree are still there.
1742          * For now let's assume the device didn't go crazy on resume,
1743          * and device drivers will know about any resume quirks.
1744          */
1745         status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1746         if (status >= 0)
1747                 status = (status == 2 ? 0 : -ENODEV);
1748
1749         if (status)
1750                 dev_dbg(&udev->dev,
1751                         "gone after usb resume? status %d\n",
1752                         status);
1753         else if (udev->actconfig) {
1754                 le16_to_cpus(&devstatus);
1755                 if ((devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
1756                                 && udev->parent) {
1757                         status = usb_control_msg(udev,
1758                                         usb_sndctrlpipe(udev, 0),
1759                                         USB_REQ_CLEAR_FEATURE,
1760                                                 USB_RECIP_DEVICE,
1761                                         USB_DEVICE_REMOTE_WAKEUP, 0,
1762                                         NULL, 0,
1763                                         USB_CTRL_SET_TIMEOUT);
1764                         if (status)
1765                                 dev_dbg(&udev->dev, "disable remote "
1766                                         "wakeup, status %d\n", status);
1767                 }
1768                 status = 0;
1769
1770         } else if (udev->devnum <= 0) {
1771                 dev_dbg(&udev->dev, "bogus resume!\n");
1772                 status = -EINVAL;
1773         }
1774         return status;
1775 }
1776
1777 static int
1778 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1779 {
1780         int     status;
1781         u16     portchange, portstatus;
1782
1783         /* Skip the initial Clear-Suspend step for a remote wakeup */
1784         status = hub_port_status(hub, port1, &portstatus, &portchange);
1785         if (status == 0 && !(portstatus & USB_PORT_STAT_SUSPEND))
1786                 goto SuspendCleared;
1787
1788         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1789
1790         set_bit(port1, hub->busy_bits);
1791
1792         /* see 7.1.7.7; affects power usage, but not budgeting */
1793         status = clear_port_feature(hub->hdev,
1794                         port1, USB_PORT_FEAT_SUSPEND);
1795         if (status) {
1796                 dev_dbg(hub->intfdev,
1797                         "can't resume port %d, status %d\n",
1798                         port1, status);
1799         } else {
1800                 /* drive resume for at least 20 msec */
1801                 if (udev)
1802                         dev_dbg(&udev->dev, "usb %sresume\n",
1803                                         udev->auto_pm ? "auto-" : "");
1804                 msleep(25);
1805
1806 #define LIVE_FLAGS      ( USB_PORT_STAT_POWER \
1807                         | USB_PORT_STAT_ENABLE \
1808                         | USB_PORT_STAT_CONNECTION)
1809
1810                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1811                  * stop resume signaling.  Then finish the resume
1812                  * sequence.
1813                  */
1814                 status = hub_port_status(hub, port1, &portstatus, &portchange);
1815 SuspendCleared:
1816                 if (status < 0
1817                                 || (portstatus & LIVE_FLAGS) != LIVE_FLAGS
1818                                 || (portstatus & USB_PORT_STAT_SUSPEND) != 0
1819                                 ) {
1820                         dev_dbg(hub->intfdev,
1821                                 "port %d status %04x.%04x after resume, %d\n",
1822                                 port1, portchange, portstatus, status);
1823                         if (status >= 0)
1824                                 status = -ENODEV;
1825                 } else {
1826                         if (portchange & USB_PORT_STAT_C_SUSPEND)
1827                                 clear_port_feature(hub->hdev, port1,
1828                                                 USB_PORT_FEAT_C_SUSPEND);
1829                         /* TRSMRCY = 10 msec */
1830                         msleep(10);
1831                         if (udev)
1832                                 status = finish_port_resume(udev);
1833                 }
1834         }
1835         if (status < 0)
1836                 hub_port_logical_disconnect(hub, port1);
1837
1838         clear_bit(port1, hub->busy_bits);
1839         if (!hub->hdev->parent && !hub->busy_bits[0])
1840                 usb_enable_root_hub_irq(hub->hdev->bus);
1841
1842         return status;
1843 }
1844
1845 /*
1846  * usb_port_resume - re-activate a suspended usb device's upstream port
1847  * @udev: device to re-activate
1848  * Context: must be able to sleep; device not locked; pm locks held
1849  *
1850  * This will re-activate the suspended device, increasing power usage
1851  * while letting drivers communicate again with its endpoints.
1852  * USB resume explicitly guarantees that the power session between
1853  * the host and the device is the same as it was when the device
1854  * suspended.
1855  *
1856  * Returns 0 on success, else negative errno.
1857  */
1858 int usb_port_resume(struct usb_device *udev)
1859 {
1860         int     status;
1861
1862         /* we change the device's upstream USB link,
1863          * but root hubs have no upstream USB link.
1864          */
1865         if (udev->parent) {
1866                 // NOTE this fails if parent is also suspended...
1867                 status = hub_port_resume(hdev_to_hub(udev->parent),
1868                                 udev->portnum, udev);
1869         } else {
1870                 dev_dbg(&udev->dev, "usb %sresume\n",
1871                                 udev->auto_pm ? "auto-" : "");
1872                 status = finish_port_resume(udev);
1873         }
1874         if (status < 0)
1875                 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
1876         return status;
1877 }
1878
1879 static int remote_wakeup(struct usb_device *udev)
1880 {
1881         int     status = 0;
1882
1883         usb_lock_device(udev);
1884         if (udev->state == USB_STATE_SUSPENDED) {
1885                 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
1886                 status = usb_autoresume_device(udev);
1887
1888                 /* Give the interface drivers a chance to do something,
1889                  * then autosuspend the device again. */
1890                 if (status == 0)
1891                         usb_autosuspend_device(udev);
1892         }
1893         usb_unlock_device(udev);
1894         return status;
1895 }
1896
1897 #else   /* CONFIG_USB_SUSPEND */
1898
1899 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
1900
1901 int usb_port_suspend(struct usb_device *udev)
1902 {
1903         return 0;
1904 }
1905
1906 static inline int
1907 finish_port_resume(struct usb_device *udev)
1908 {
1909         return 0;
1910 }
1911
1912 static inline int
1913 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1914 {
1915         return 0;
1916 }
1917
1918 int usb_port_resume(struct usb_device *udev)
1919 {
1920         return 0;
1921 }
1922
1923 static inline int remote_wakeup(struct usb_device *udev)
1924 {
1925         return 0;
1926 }
1927
1928 #endif
1929
1930 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
1931 {
1932         struct usb_hub          *hub = usb_get_intfdata (intf);
1933         struct usb_device       *hdev = hub->hdev;
1934         unsigned                port1;
1935
1936         /* fail if children aren't already suspended */
1937         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1938                 struct usb_device       *udev;
1939
1940                 udev = hdev->children [port1-1];
1941                 if (udev && msg.event == PM_EVENT_SUSPEND &&
1942 #ifdef  CONFIG_USB_SUSPEND
1943                                 udev->state != USB_STATE_SUSPENDED
1944 #else
1945                                 udev->dev.power.power_state.event
1946                                         == PM_EVENT_ON
1947 #endif
1948                                 ) {
1949                         if (!hdev->auto_pm)
1950                                 dev_dbg(&intf->dev, "port %d nyet suspended\n",
1951                                                 port1);
1952                         return -EBUSY;
1953                 }
1954         }
1955
1956         dev_dbg(&intf->dev, "%s\n", __FUNCTION__);
1957
1958         /* "global suspend" of the downstream HC-to-USB interface */
1959         if (!hdev->parent) {
1960                 struct usb_bus  *bus = hdev->bus;
1961                 if (bus) {
1962                         int     status = hcd_bus_suspend (bus);
1963
1964                         if (status != 0) {
1965                                 dev_dbg(&hdev->dev, "'global' suspend %d\n",
1966                                         status);
1967                                 return status;
1968                         }
1969                 } else
1970                         return -EOPNOTSUPP;
1971         }
1972
1973         /* stop khubd and related activity */
1974         hub_quiesce(hub);
1975         return 0;
1976 }
1977
1978 static int hub_resume(struct usb_interface *intf)
1979 {
1980         struct usb_hub          *hub = usb_get_intfdata (intf);
1981         struct usb_device       *hdev = hub->hdev;
1982         int                     status;
1983
1984         dev_dbg(&intf->dev, "%s\n", __FUNCTION__);
1985
1986         /* "global resume" of the downstream HC-to-USB interface */
1987         if (!hdev->parent) {
1988                 struct usb_bus  *bus = hdev->bus;
1989                 if (bus) {
1990                         status = hcd_bus_resume (bus);
1991                         if (status) {
1992                                 dev_dbg(&intf->dev, "'global' resume %d\n",
1993                                         status);
1994                                 return status;
1995                         }
1996                 } else
1997                         return -EOPNOTSUPP;
1998                 if (status == 0) {
1999                         /* TRSMRCY = 10 msec */
2000                         msleep(10);
2001                 }
2002         }
2003
2004         /* tell khubd to look for changes on this hub */
2005         hub_activate(hub);
2006         return 0;
2007 }
2008
2009 #else   /* CONFIG_PM */
2010
2011 static inline int remote_wakeup(struct usb_device *udev)
2012 {
2013         return 0;
2014 }
2015
2016 #define hub_suspend NULL
2017 #define hub_resume NULL
2018 #endif
2019
2020 void usb_resume_root_hub(struct usb_device *hdev)
2021 {
2022         struct usb_hub *hub = hdev_to_hub(hdev);
2023
2024         kick_khubd(hub);
2025 }
2026
2027
2028 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2029  *
2030  * Between connect detection and reset signaling there must be a delay
2031  * of 100ms at least for debounce and power-settling.  The corresponding
2032  * timer shall restart whenever the downstream port detects a disconnect.
2033  *
2034  * Apparently there are some bluetooth and irda-dongles and a number of
2035  * low-speed devices for which this debounce period may last over a second.
2036  * Not covered by the spec - but easy to deal with.
2037  *
2038  * This implementation uses a 1500ms total debounce timeout; if the
2039  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
2040  * every 25ms for transient disconnects.  When the port status has been
2041  * unchanged for 100ms it returns the port status.
2042  */
2043
2044 #define HUB_DEBOUNCE_TIMEOUT    1500
2045 #define HUB_DEBOUNCE_STEP         25
2046 #define HUB_DEBOUNCE_STABLE      100
2047
2048 static int hub_port_debounce(struct usb_hub *hub, int port1)
2049 {
2050         int ret;
2051         int total_time, stable_time = 0;
2052         u16 portchange, portstatus;
2053         unsigned connection = 0xffff;
2054
2055         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2056                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2057                 if (ret < 0)
2058                         return ret;
2059
2060                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2061                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2062                         stable_time += HUB_DEBOUNCE_STEP;
2063                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2064                                 break;
2065                 } else {
2066                         stable_time = 0;
2067                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2068                 }
2069
2070                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2071                         clear_port_feature(hub->hdev, port1,
2072                                         USB_PORT_FEAT_C_CONNECTION);
2073                 }
2074
2075                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2076                         break;
2077                 msleep(HUB_DEBOUNCE_STEP);
2078         }
2079
2080         dev_dbg (hub->intfdev,
2081                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2082                 port1, total_time, stable_time, portstatus);
2083
2084         if (stable_time < HUB_DEBOUNCE_STABLE)
2085                 return -ETIMEDOUT;
2086         return portstatus;
2087 }
2088
2089 static void ep0_reinit(struct usb_device *udev)
2090 {
2091         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2092         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2093         udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2094 }
2095
2096 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2097 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2098
2099 static int hub_set_address(struct usb_device *udev)
2100 {
2101         int retval;
2102
2103         if (udev->devnum == 0)
2104                 return -EINVAL;
2105         if (udev->state == USB_STATE_ADDRESS)
2106                 return 0;
2107         if (udev->state != USB_STATE_DEFAULT)
2108                 return -EINVAL;
2109         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2110                 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2111                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2112         if (retval == 0) {
2113                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2114                 ep0_reinit(udev);
2115         }
2116         return retval;
2117 }
2118
2119 /* Reset device, (re)assign address, get device descriptor.
2120  * Device connection must be stable, no more debouncing needed.
2121  * Returns device in USB_STATE_ADDRESS, except on error.
2122  *
2123  * If this is called for an already-existing device (as part of
2124  * usb_reset_device), the caller must own the device lock.  For a
2125  * newly detected device that is not accessible through any global
2126  * pointers, it's not necessary to lock the device.
2127  */
2128 static int
2129 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2130                 int retry_counter)
2131 {
2132         static DEFINE_MUTEX(usb_address0_mutex);
2133
2134         struct usb_device       *hdev = hub->hdev;
2135         int                     i, j, retval;
2136         unsigned                delay = HUB_SHORT_RESET_TIME;
2137         enum usb_device_speed   oldspeed = udev->speed;
2138         char                    *speed, *type;
2139
2140         /* root hub ports have a slightly longer reset period
2141          * (from USB 2.0 spec, section 7.1.7.5)
2142          */
2143         if (!hdev->parent) {
2144                 delay = HUB_ROOT_RESET_TIME;
2145                 if (port1 == hdev->bus->otg_port)
2146                         hdev->bus->b_hnp_enable = 0;
2147         }
2148
2149         /* Some low speed devices have problems with the quick delay, so */
2150         /*  be a bit pessimistic with those devices. RHbug #23670 */
2151         if (oldspeed == USB_SPEED_LOW)
2152                 delay = HUB_LONG_RESET_TIME;
2153
2154         mutex_lock(&usb_address0_mutex);
2155
2156         /* Reset the device; full speed may morph to high speed */
2157         retval = hub_port_reset(hub, port1, udev, delay);
2158         if (retval < 0)         /* error or disconnect */
2159                 goto fail;
2160                                 /* success, speed is known */
2161         retval = -ENODEV;
2162
2163         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2164                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2165                 goto fail;
2166         }
2167         oldspeed = udev->speed;
2168
2169         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2170          * it's fixed size except for full speed devices.
2171          * For Wireless USB devices, ep0 max packet is always 512 (tho
2172          * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
2173          */
2174         switch (udev->speed) {
2175         case USB_SPEED_VARIABLE:        /* fixed at 512 */
2176                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(512);
2177                 break;
2178         case USB_SPEED_HIGH:            /* fixed at 64 */
2179                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2180                 break;
2181         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2182                 /* to determine the ep0 maxpacket size, try to read
2183                  * the device descriptor to get bMaxPacketSize0 and
2184                  * then correct our initial guess.
2185                  */
2186                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2187                 break;
2188         case USB_SPEED_LOW:             /* fixed at 8 */
2189                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2190                 break;
2191         default:
2192                 goto fail;
2193         }
2194
2195         type = "";
2196         switch (udev->speed) {
2197         case USB_SPEED_LOW:     speed = "low";  break;
2198         case USB_SPEED_FULL:    speed = "full"; break;
2199         case USB_SPEED_HIGH:    speed = "high"; break;
2200         case USB_SPEED_VARIABLE:
2201                                 speed = "variable";
2202                                 type = "Wireless ";
2203                                 break;
2204         default:                speed = "?";    break;
2205         }
2206         dev_info (&udev->dev,
2207                   "%s %s speed %sUSB device using %s and address %d\n",
2208                   (udev->config) ? "reset" : "new", speed, type,
2209                   udev->bus->controller->driver->name, udev->devnum);
2210
2211         /* Set up TT records, if needed  */
2212         if (hdev->tt) {
2213                 udev->tt = hdev->tt;
2214                 udev->ttport = hdev->ttport;
2215         } else if (udev->speed != USB_SPEED_HIGH
2216                         && hdev->speed == USB_SPEED_HIGH) {
2217                 udev->tt = &hub->tt;
2218                 udev->ttport = port1;
2219         }
2220
2221         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2222          * Because device hardware and firmware is sometimes buggy in
2223          * this area, and this is how Linux has done it for ages.
2224          * Change it cautiously.
2225          *
2226          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2227          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2228          * so it may help with some non-standards-compliant devices.
2229          * Otherwise we start with SET_ADDRESS and then try to read the
2230          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2231          * value.
2232          */
2233         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2234                 if (USE_NEW_SCHEME(retry_counter)) {
2235                         struct usb_device_descriptor *buf;
2236                         int r = 0;
2237
2238 #define GET_DESCRIPTOR_BUFSIZE  64
2239                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2240                         if (!buf) {
2241                                 retval = -ENOMEM;
2242                                 continue;
2243                         }
2244
2245                         /* Use a short timeout the first time through,
2246                          * so that recalcitrant full-speed devices with
2247                          * 8- or 16-byte ep0-maxpackets won't slow things
2248                          * down tremendously by NAKing the unexpectedly
2249                          * early status stage.  Also, retry on all errors;
2250                          * some devices are flakey.
2251                          * 255 is for WUSB devices, we actually need to use 512.
2252                          * WUSB1.0[4.8.1].
2253                          */
2254                         for (j = 0; j < 3; ++j) {
2255                                 buf->bMaxPacketSize0 = 0;
2256                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2257                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2258                                         USB_DT_DEVICE << 8, 0,
2259                                         buf, GET_DESCRIPTOR_BUFSIZE,
2260                                         (i ? USB_CTRL_GET_TIMEOUT : 1000));
2261                                 switch (buf->bMaxPacketSize0) {
2262                                 case 8: case 16: case 32: case 64: case 255:
2263                                         if (buf->bDescriptorType ==
2264                                                         USB_DT_DEVICE) {
2265                                                 r = 0;
2266                                                 break;
2267                                         }
2268                                         /* FALL THROUGH */
2269                                 default:
2270                                         if (r == 0)
2271                                                 r = -EPROTO;
2272                                         break;
2273                                 }
2274                                 if (r == 0)
2275                                         break;
2276                         }
2277                         udev->descriptor.bMaxPacketSize0 =
2278                                         buf->bMaxPacketSize0;
2279                         kfree(buf);
2280
2281                         retval = hub_port_reset(hub, port1, udev, delay);
2282                         if (retval < 0)         /* error or disconnect */
2283                                 goto fail;
2284                         if (oldspeed != udev->speed) {
2285                                 dev_dbg(&udev->dev,
2286                                         "device reset changed speed!\n");
2287                                 retval = -ENODEV;
2288                                 goto fail;
2289                         }
2290                         if (r) {
2291                                 dev_err(&udev->dev, "device descriptor "
2292                                                 "read/%s, error %d\n",
2293                                                 "64", r);
2294                                 retval = -EMSGSIZE;
2295                                 continue;
2296                         }
2297 #undef GET_DESCRIPTOR_BUFSIZE
2298                 }
2299
2300                 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2301                         retval = hub_set_address(udev);
2302                         if (retval >= 0)
2303                                 break;
2304                         msleep(200);
2305                 }
2306                 if (retval < 0) {
2307                         dev_err(&udev->dev,
2308                                 "device not accepting address %d, error %d\n",
2309                                 udev->devnum, retval);
2310                         goto fail;
2311                 }
2312
2313                 /* cope with hardware quirkiness:
2314                  *  - let SET_ADDRESS settle, some device hardware wants it
2315                  *  - read ep0 maxpacket even for high and low speed,
2316                  */
2317                 msleep(10);
2318                 if (USE_NEW_SCHEME(retry_counter))
2319                         break;
2320
2321                 retval = usb_get_device_descriptor(udev, 8);
2322                 if (retval < 8) {
2323                         dev_err(&udev->dev, "device descriptor "
2324                                         "read/%s, error %d\n",
2325                                         "8", retval);
2326                         if (retval >= 0)
2327                                 retval = -EMSGSIZE;
2328                 } else {
2329                         retval = 0;
2330                         break;
2331                 }
2332         }
2333         if (retval)
2334                 goto fail;
2335
2336         i = udev->descriptor.bMaxPacketSize0 == 0xff?
2337             512 : udev->descriptor.bMaxPacketSize0;
2338         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2339                 if (udev->speed != USB_SPEED_FULL ||
2340                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2341                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2342                         retval = -EMSGSIZE;
2343                         goto fail;
2344                 }
2345                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2346                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2347                 ep0_reinit(udev);
2348         }
2349
2350         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2351         if (retval < (signed)sizeof(udev->descriptor)) {
2352                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2353                         "all", retval);
2354                 if (retval >= 0)
2355                         retval = -ENOMSG;
2356                 goto fail;
2357         }
2358
2359         retval = 0;
2360
2361 fail:
2362         if (retval)
2363                 hub_port_disable(hub, port1, 0);
2364         mutex_unlock(&usb_address0_mutex);
2365         return retval;
2366 }
2367
2368 static void
2369 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2370 {
2371         struct usb_qualifier_descriptor *qual;
2372         int                             status;
2373
2374         qual = kmalloc (sizeof *qual, GFP_KERNEL);
2375         if (qual == NULL)
2376                 return;
2377
2378         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2379                         qual, sizeof *qual);
2380         if (status == sizeof *qual) {
2381                 dev_info(&udev->dev, "not running at top speed; "
2382                         "connect to a high speed hub\n");
2383                 /* hub LEDs are probably harder to miss than syslog */
2384                 if (hub->has_indicators) {
2385                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2386                         schedule_delayed_work (&hub->leds, 0);
2387                 }
2388         }
2389         kfree(qual);
2390 }
2391
2392 static unsigned
2393 hub_power_remaining (struct usb_hub *hub)
2394 {
2395         struct usb_device *hdev = hub->hdev;
2396         int remaining;
2397         int port1;
2398
2399         if (!hub->limited_power)
2400                 return 0;
2401
2402         remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
2403         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
2404                 struct usb_device       *udev = hdev->children[port1 - 1];
2405                 int                     delta;
2406
2407                 if (!udev)
2408                         continue;
2409
2410                 /* Unconfigured devices may not use more than 100mA,
2411                  * or 8mA for OTG ports */
2412                 if (udev->actconfig)
2413                         delta = udev->actconfig->desc.bMaxPower * 2;
2414                 else if (port1 != udev->bus->otg_port || hdev->parent)
2415                         delta = 100;
2416                 else
2417                         delta = 8;
2418                 if (delta > hub->mA_per_port)
2419                         dev_warn(&udev->dev, "%dmA is over %umA budget "
2420                                         "for port %d!\n",
2421                                         delta, hub->mA_per_port, port1);
2422                 remaining -= delta;
2423         }
2424         if (remaining < 0) {
2425                 dev_warn(hub->intfdev, "%dmA over power budget!\n",
2426                         - remaining);
2427                 remaining = 0;
2428         }
2429         return remaining;
2430 }
2431
2432 /* Handle physical or logical connection change events.
2433  * This routine is called when:
2434  *      a port connection-change occurs;
2435  *      a port enable-change occurs (often caused by EMI);
2436  *      usb_reset_device() encounters changed descriptors (as from
2437  *              a firmware download)
2438  * caller already locked the hub
2439  */
2440 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2441                                         u16 portstatus, u16 portchange)
2442 {
2443         struct usb_device *hdev = hub->hdev;
2444         struct device *hub_dev = hub->intfdev;
2445         u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2446         int status, i;
2447
2448         dev_dbg (hub_dev,
2449                 "port %d, status %04x, change %04x, %s\n",
2450                 port1, portstatus, portchange, portspeed (portstatus));
2451
2452         if (hub->has_indicators) {
2453                 set_port_led(hub, port1, HUB_LED_AUTO);
2454                 hub->indicator[port1-1] = INDICATOR_AUTO;
2455         }
2456
2457         /* Disconnect any existing devices under this port */
2458         if (hdev->children[port1-1])
2459                 usb_disconnect(&hdev->children[port1-1]);
2460         clear_bit(port1, hub->change_bits);
2461
2462 #ifdef  CONFIG_USB_OTG
2463         /* during HNP, don't repeat the debounce */
2464         if (hdev->bus->is_b_host)
2465                 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2466 #endif
2467
2468         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2469                 status = hub_port_debounce(hub, port1);
2470                 if (status < 0) {
2471                         dev_err (hub_dev,
2472                                 "connect-debounce failed, port %d disabled\n",
2473                                 port1);
2474                         goto done;
2475                 }
2476                 portstatus = status;
2477         }
2478
2479         /* Return now if nothing is connected */
2480         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2481
2482                 /* maybe switch power back on (e.g. root hub was reset) */
2483                 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
2484                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2485                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2486
2487                 if (portstatus & USB_PORT_STAT_ENABLE)
2488                         goto done;
2489                 return;
2490         }
2491
2492 #ifdef  CONFIG_USB_SUSPEND
2493         /* If something is connected, but the port is suspended, wake it up. */
2494         if (portstatus & USB_PORT_STAT_SUSPEND) {
2495                 status = hub_port_resume(hub, port1, NULL);
2496                 if (status < 0) {
2497                         dev_dbg(hub_dev,
2498                                 "can't clear suspend on port %d; %d\n",
2499                                 port1, status);
2500                         goto done;
2501                 }
2502         }
2503 #endif
2504
2505         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2506                 struct usb_device *udev;
2507
2508                 /* reallocate for each attempt, since references
2509                  * to the previous one can escape in various ways
2510                  */
2511                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2512                 if (!udev) {
2513                         dev_err (hub_dev,
2514                                 "couldn't allocate port %d usb_device\n",
2515                                 port1);
2516                         goto done;
2517                 }
2518
2519                 usb_set_device_state(udev, USB_STATE_POWERED);
2520                 udev->speed = USB_SPEED_UNKNOWN;
2521                 udev->bus_mA = hub->mA_per_port;
2522                 udev->level = hdev->level + 1;
2523
2524                 /* set the address */
2525                 choose_address(udev);
2526                 if (udev->devnum <= 0) {
2527                         status = -ENOTCONN;     /* Don't retry */
2528                         goto loop;
2529                 }
2530
2531                 /* reset and get descriptor */
2532                 status = hub_port_init(hub, udev, port1, i);
2533                 if (status < 0)
2534                         goto loop;
2535
2536                 /* consecutive bus-powered hubs aren't reliable; they can
2537                  * violate the voltage drop budget.  if the new child has
2538                  * a "powered" LED, users should notice we didn't enable it
2539                  * (without reading syslog), even without per-port LEDs
2540                  * on the parent.
2541                  */
2542                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2543                                 && udev->bus_mA <= 100) {
2544                         u16     devstat;
2545
2546                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2547                                         &devstat);
2548                         if (status < 2) {
2549                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2550                                 goto loop_disable;
2551                         }
2552                         le16_to_cpus(&devstat);
2553                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2554                                 dev_err(&udev->dev,
2555                                         "can't connect bus-powered hub "
2556                                         "to this port\n");
2557                                 if (hub->has_indicators) {
2558                                         hub->indicator[port1-1] =
2559                                                 INDICATOR_AMBER_BLINK;
2560                                         schedule_delayed_work (&hub->leds, 0);
2561                                 }
2562                                 status = -ENOTCONN;     /* Don't retry */
2563                                 goto loop_disable;
2564                         }
2565                 }
2566
2567                 /* check for devices running slower than they could */
2568                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2569                                 && udev->speed == USB_SPEED_FULL
2570                                 && highspeed_hubs != 0)
2571                         check_highspeed (hub, udev, port1);
2572
2573                 /* Store the parent's children[] pointer.  At this point
2574                  * udev becomes globally accessible, although presumably
2575                  * no one will look at it until hdev is unlocked.
2576                  */
2577                 status = 0;
2578
2579                 /* We mustn't add new devices if the parent hub has
2580                  * been disconnected; we would race with the
2581                  * recursively_mark_NOTATTACHED() routine.
2582                  */
2583                 spin_lock_irq(&device_state_lock);
2584                 if (hdev->state == USB_STATE_NOTATTACHED)
2585                         status = -ENOTCONN;
2586                 else
2587                         hdev->children[port1-1] = udev;
2588                 spin_unlock_irq(&device_state_lock);
2589
2590                 /* Run it through the hoops (find a driver, etc) */
2591                 if (!status) {
2592                         status = usb_new_device(udev);
2593                         if (status) {
2594                                 spin_lock_irq(&device_state_lock);
2595                                 hdev->children[port1-1] = NULL;
2596                                 spin_unlock_irq(&device_state_lock);
2597                         }
2598                 }
2599
2600                 if (status)
2601                         goto loop_disable;
2602
2603                 status = hub_power_remaining(hub);
2604                 if (status)
2605                         dev_dbg(hub_dev, "%dmA power budget left\n", status);
2606
2607                 return;
2608
2609 loop_disable:
2610                 hub_port_disable(hub, port1, 1);
2611 loop:
2612                 ep0_reinit(udev);
2613                 release_address(udev);
2614                 usb_put_dev(udev);
2615                 if (status == -ENOTCONN)
2616                         break;
2617         }
2618
2619 done:
2620         hub_port_disable(hub, port1, 1);
2621 }
2622
2623 static void hub_events(void)
2624 {
2625         struct list_head *tmp;
2626         struct usb_device *hdev;
2627         struct usb_interface *intf;
2628         struct usb_hub *hub;
2629         struct device *hub_dev;
2630         u16 hubstatus;
2631         u16 hubchange;
2632         u16 portstatus;
2633         u16 portchange;
2634         int i, ret;
2635         int connect_change;
2636
2637         /*
2638          *  We restart the list every time to avoid a deadlock with
2639          * deleting hubs downstream from this one. This should be
2640          * safe since we delete the hub from the event list.
2641          * Not the most efficient, but avoids deadlocks.
2642          */
2643         while (1) {
2644
2645                 /* Grab the first entry at the beginning of the list */
2646                 spin_lock_irq(&hub_event_lock);
2647                 if (list_empty(&hub_event_list)) {
2648                         spin_unlock_irq(&hub_event_lock);
2649                         break;
2650                 }
2651
2652                 tmp = hub_event_list.next;
2653                 list_del_init(tmp);
2654
2655                 hub = list_entry(tmp, struct usb_hub, event_list);
2656                 hdev = hub->hdev;
2657                 intf = to_usb_interface(hub->intfdev);
2658                 hub_dev = &intf->dev;
2659
2660                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
2661                                 hdev->state, hub->descriptor
2662                                         ? hub->descriptor->bNbrPorts
2663                                         : 0,
2664                                 /* NOTE: expects max 15 ports... */
2665                                 (u16) hub->change_bits[0],
2666                                 (u16) hub->event_bits[0]);
2667
2668                 usb_get_intf(intf);
2669                 spin_unlock_irq(&hub_event_lock);
2670
2671                 /* Lock the device, then check to see if we were
2672                  * disconnected while waiting for the lock to succeed. */
2673                 if (locktree(hdev) < 0) {
2674                         usb_put_intf(intf);
2675                         continue;
2676                 }
2677                 if (hub != usb_get_intfdata(intf))
2678                         goto loop;
2679
2680                 /* If the hub has died, clean up after it */
2681                 if (hdev->state == USB_STATE_NOTATTACHED) {
2682                         hub->error = -ENODEV;
2683                         hub_pre_reset(intf);
2684                         goto loop;
2685                 }
2686
2687                 /* Autoresume */
2688                 ret = usb_autopm_get_interface(intf);
2689                 if (ret) {
2690                         dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
2691                         goto loop;
2692                 }
2693
2694                 /* If this is an inactive hub, do nothing */
2695                 if (hub->quiescing)
2696                         goto loop_autopm;
2697
2698                 if (hub->error) {
2699                         dev_dbg (hub_dev, "resetting for error %d\n",
2700                                 hub->error);
2701
2702                         ret = usb_reset_composite_device(hdev, intf);
2703                         if (ret) {
2704                                 dev_dbg (hub_dev,
2705                                         "error resetting hub: %d\n", ret);
2706                                 goto loop_autopm;
2707                         }
2708
2709                         hub->nerrors = 0;
2710                         hub->error = 0;
2711                 }
2712
2713                 /* deal with port status changes */
2714                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2715                         if (test_bit(i, hub->busy_bits))
2716                                 continue;
2717                         connect_change = test_bit(i, hub->change_bits);
2718                         if (!test_and_clear_bit(i, hub->event_bits) &&
2719                                         !connect_change && !hub->activating)
2720                                 continue;
2721
2722                         ret = hub_port_status(hub, i,
2723                                         &portstatus, &portchange);
2724                         if (ret < 0)
2725                                 continue;
2726
2727                         if (hub->activating && !hdev->children[i-1] &&
2728                                         (portstatus &
2729                                                 USB_PORT_STAT_CONNECTION))
2730                                 connect_change = 1;
2731
2732                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2733                                 clear_port_feature(hdev, i,
2734                                         USB_PORT_FEAT_C_CONNECTION);
2735                                 connect_change = 1;
2736                         }
2737
2738                         if (portchange & USB_PORT_STAT_C_ENABLE) {
2739                                 if (!connect_change)
2740                                         dev_dbg (hub_dev,
2741                                                 "port %d enable change, "
2742                                                 "status %08x\n",
2743                                                 i, portstatus);
2744                                 clear_port_feature(hdev, i,
2745                                         USB_PORT_FEAT_C_ENABLE);
2746
2747                                 /*
2748                                  * EM interference sometimes causes badly
2749                                  * shielded USB devices to be shutdown by
2750                                  * the hub, this hack enables them again.
2751                                  * Works at least with mouse driver.
2752                                  */
2753                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
2754                                     && !connect_change
2755                                     && hdev->children[i-1]) {
2756                                         dev_err (hub_dev,
2757                                             "port %i "
2758                                             "disabled by hub (EMI?), "
2759                                             "re-enabling...\n",
2760                                                 i);
2761                                         connect_change = 1;
2762                                 }
2763                         }
2764
2765                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2766                                 clear_port_feature(hdev, i,
2767                                         USB_PORT_FEAT_C_SUSPEND);
2768                                 if (hdev->children[i-1]) {
2769                                         ret = remote_wakeup(hdev->
2770                                                         children[i-1]);
2771                                         if (ret < 0)
2772                                                 connect_change = 1;
2773                                 } else {
2774                                         ret = -ENODEV;
2775                                         hub_port_disable(hub, i, 1);
2776                                 }
2777                                 dev_dbg (hub_dev,
2778                                         "resume on port %d, status %d\n",
2779                                         i, ret);
2780                         }
2781
2782                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2783                                 dev_err (hub_dev,
2784                                         "over-current change on port %d\n",
2785                                         i);
2786                                 clear_port_feature(hdev, i,
2787                                         USB_PORT_FEAT_C_OVER_CURRENT);
2788                                 hub_power_on(hub);
2789                         }
2790
2791                         if (portchange & USB_PORT_STAT_C_RESET) {
2792                                 dev_dbg (hub_dev,
2793                                         "reset change on port %d\n",
2794                                         i);
2795                                 clear_port_feature(hdev, i,
2796                                         USB_PORT_FEAT_C_RESET);
2797                         }
2798
2799                         if (connect_change)
2800                                 hub_port_connect_change(hub, i,
2801                                                 portstatus, portchange);
2802                 } /* end for i */
2803
2804                 /* deal with hub status changes */
2805                 if (test_and_clear_bit(0, hub->event_bits) == 0)
2806                         ;       /* do nothing */
2807                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2808                         dev_err (hub_dev, "get_hub_status failed\n");
2809                 else {
2810                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2811                                 dev_dbg (hub_dev, "power change\n");
2812                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2813                                 if (hubstatus & HUB_STATUS_LOCAL_POWER)
2814                                         /* FIXME: Is this always true? */
2815                                         hub->limited_power = 0;
2816                                 else
2817                                         hub->limited_power = 1;
2818                         }
2819                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
2820                                 dev_dbg (hub_dev, "overcurrent change\n");
2821                                 msleep(500);    /* Cool down */
2822                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2823                                 hub_power_on(hub);
2824                         }
2825                 }
2826
2827                 hub->activating = 0;
2828
2829                 /* If this is a root hub, tell the HCD it's okay to
2830                  * re-enable port-change interrupts now. */
2831                 if (!hdev->parent && !hub->busy_bits[0])
2832                         usb_enable_root_hub_irq(hdev->bus);
2833
2834 loop_autopm:
2835                 /* Allow autosuspend if we're not going to run again */
2836                 if (list_empty(&hub->event_list))
2837                         usb_autopm_enable(intf);
2838 loop:
2839                 usb_unlock_device(hdev);
2840                 usb_put_intf(intf);
2841
2842         } /* end while (1) */
2843 }
2844
2845 static int hub_thread(void *__unused)
2846 {
2847         do {
2848                 hub_events();
2849                 wait_event_interruptible(khubd_wait,
2850                                 !list_empty(&hub_event_list) ||
2851                                 kthread_should_stop());
2852                 try_to_freeze();
2853         } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2854
2855         pr_debug("%s: khubd exiting\n", usbcore_name);
2856         return 0;
2857 }
2858
2859 static struct usb_device_id hub_id_table [] = {
2860     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2861       .bDeviceClass = USB_CLASS_HUB},
2862     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2863       .bInterfaceClass = USB_CLASS_HUB},
2864     { }                                         /* Terminating entry */
2865 };
2866
2867 MODULE_DEVICE_TABLE (usb, hub_id_table);
2868
2869 static struct usb_driver hub_driver = {
2870         .name =         "hub",
2871         .probe =        hub_probe,
2872         .disconnect =   hub_disconnect,
2873         .suspend =      hub_suspend,
2874         .resume =       hub_resume,
2875         .pre_reset =    hub_pre_reset,
2876         .post_reset =   hub_post_reset,
2877         .ioctl =        hub_ioctl,
2878         .id_table =     hub_id_table,
2879         .supports_autosuspend = 1,
2880 };
2881
2882 int usb_hub_init(void)
2883 {
2884         if (usb_register(&hub_driver) < 0) {
2885                 printk(KERN_ERR "%s: can't register hub driver\n",
2886                         usbcore_name);
2887                 return -1;
2888         }
2889
2890         khubd_task = kthread_run(hub_thread, NULL, "khubd");
2891         if (!IS_ERR(khubd_task))
2892                 return 0;
2893
2894         /* Fall through if kernel_thread failed */
2895         usb_deregister(&hub_driver);
2896         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2897
2898         return -1;
2899 }
2900
2901 void usb_hub_cleanup(void)
2902 {
2903         kthread_stop(khubd_task);
2904
2905         /*
2906          * Hub resources are freed for us by usb_deregister. It calls
2907          * usb_driver_purge on every device which in turn calls that
2908          * devices disconnect function if it is using this driver.
2909          * The hub_disconnect function takes care of releasing the
2910          * individual hub resources. -greg
2911          */
2912         usb_deregister(&hub_driver);
2913 } /* usb_hub_cleanup() */
2914
2915 static int config_descriptors_changed(struct usb_device *udev)
2916 {
2917         unsigned                        index;
2918         unsigned                        len = 0;
2919         struct usb_config_descriptor    *buf;
2920
2921         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2922                 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2923                         len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2924         }
2925         buf = kmalloc (len, GFP_KERNEL);
2926         if (buf == NULL) {
2927                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2928                 /* assume the worst */
2929                 return 1;
2930         }
2931         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2932                 int length;
2933                 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2934
2935                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2936                                 old_length);
2937                 if (length < old_length) {
2938                         dev_dbg(&udev->dev, "config index %d, error %d\n",
2939                                         index, length);
2940                         break;
2941                 }
2942                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2943                                 != 0) {
2944                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2945                                 index, buf->bConfigurationValue);
2946                         break;
2947                 }
2948         }
2949         kfree(buf);
2950         return index != udev->descriptor.bNumConfigurations;
2951 }
2952
2953 /**
2954  * usb_reset_device - perform a USB port reset to reinitialize a device
2955  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2956  *
2957  * WARNING - don't use this routine to reset a composite device
2958  * (one with multiple interfaces owned by separate drivers)!
2959  * Use usb_reset_composite_device() instead.
2960  *
2961  * Do a port reset, reassign the device's address, and establish its
2962  * former operating configuration.  If the reset fails, or the device's
2963  * descriptors change from their values before the reset, or the original
2964  * configuration and altsettings cannot be restored, a flag will be set
2965  * telling khubd to pretend the device has been disconnected and then
2966  * re-connected.  All drivers will be unbound, and the device will be
2967  * re-enumerated and probed all over again.
2968  *
2969  * Returns 0 if the reset succeeded, -ENODEV if the device has been
2970  * flagged for logical disconnection, or some other negative error code
2971  * if the reset wasn't even attempted.
2972  *
2973  * The caller must own the device lock.  For example, it's safe to use
2974  * this from a driver probe() routine after downloading new firmware.
2975  * For calls that might not occur during probe(), drivers should lock
2976  * the device using usb_lock_device_for_reset().
2977  */
2978 int usb_reset_device(struct usb_device *udev)
2979 {
2980         struct usb_device               *parent_hdev = udev->parent;
2981         struct usb_hub                  *parent_hub;
2982         struct usb_device_descriptor    descriptor = udev->descriptor;
2983         int                             i, ret = 0;
2984         int                             port1 = udev->portnum;
2985
2986         if (udev->state == USB_STATE_NOTATTACHED ||
2987                         udev->state == USB_STATE_SUSPENDED) {
2988                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2989                                 udev->state);
2990                 return -EINVAL;
2991         }
2992
2993         if (!parent_hdev) {
2994                 /* this requires hcd-specific logic; see OHCI hc_restart() */
2995                 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2996                 return -EISDIR;
2997         }
2998         parent_hub = hdev_to_hub(parent_hdev);
2999
3000         set_bit(port1, parent_hub->busy_bits);
3001         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
3002
3003                 /* ep0 maxpacket size may change; let the HCD know about it.
3004                  * Other endpoints will be handled by re-enumeration. */
3005                 ep0_reinit(udev);
3006                 ret = hub_port_init(parent_hub, udev, port1, i);
3007                 if (ret >= 0)
3008                         break;
3009         }
3010         clear_bit(port1, parent_hub->busy_bits);
3011         if (!parent_hdev->parent && !parent_hub->busy_bits[0])
3012                 usb_enable_root_hub_irq(parent_hdev->bus);
3013
3014         if (ret < 0)
3015                 goto re_enumerate;
3016
3017         /* Device might have changed firmware (DFU or similar) */
3018         if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
3019                         || config_descriptors_changed (udev)) {
3020                 dev_info(&udev->dev, "device firmware changed\n");
3021                 udev->descriptor = descriptor;  /* for disconnect() calls */
3022                 goto re_enumerate;
3023         }
3024
3025         if (!udev->actconfig)
3026                 goto done;
3027
3028         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3029                         USB_REQ_SET_CONFIGURATION, 0,
3030                         udev->actconfig->desc.bConfigurationValue, 0,
3031                         NULL, 0, USB_CTRL_SET_TIMEOUT);
3032         if (ret < 0) {
3033                 dev_err(&udev->dev,
3034                         "can't restore configuration #%d (error=%d)\n",
3035                         udev->actconfig->desc.bConfigurationValue, ret);
3036                 goto re_enumerate;
3037         }
3038         usb_set_device_state(udev, USB_STATE_CONFIGURED);
3039
3040         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3041                 struct usb_interface *intf = udev->actconfig->interface[i];
3042                 struct usb_interface_descriptor *desc;
3043
3044                 /* set_interface resets host side toggle even
3045                  * for altsetting zero.  the interface may have no driver.
3046                  */
3047                 desc = &intf->cur_altsetting->desc;
3048                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3049                         desc->bAlternateSetting);
3050                 if (ret < 0) {
3051                         dev_err(&udev->dev, "failed to restore interface %d "
3052                                 "altsetting %d (error=%d)\n",
3053                                 desc->bInterfaceNumber,
3054                                 desc->bAlternateSetting,
3055                                 ret);
3056                         goto re_enumerate;
3057                 }
3058         }
3059
3060 done:
3061         return 0;
3062
3063 re_enumerate:
3064         hub_port_logical_disconnect(parent_hub, port1);
3065         return -ENODEV;
3066 }
3067 EXPORT_SYMBOL(usb_reset_device);
3068
3069 /**
3070  * usb_reset_composite_device - warn interface drivers and perform a USB port reset
3071  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
3072  * @iface: interface bound to the driver making the request (optional)
3073  *
3074  * Warns all drivers bound to registered interfaces (using their pre_reset
3075  * method), performs the port reset, and then lets the drivers know that
3076  * the reset is over (using their post_reset method).
3077  *
3078  * Return value is the same as for usb_reset_device().
3079  *
3080  * The caller must own the device lock.  For example, it's safe to use
3081  * this from a driver probe() routine after downloading new firmware.
3082  * For calls that might not occur during probe(), drivers should lock
3083  * the device using usb_lock_device_for_reset().
3084  *
3085  * The interface locks are acquired during the pre_reset stage and released
3086  * during the post_reset stage.  However if iface is not NULL and is
3087  * currently being probed, we assume that the caller already owns its
3088  * lock.
3089  */
3090 int usb_reset_composite_device(struct usb_device *udev,
3091                 struct usb_interface *iface)
3092 {
3093         int ret;
3094         struct usb_host_config *config = udev->actconfig;
3095
3096         if (udev->state == USB_STATE_NOTATTACHED ||
3097                         udev->state == USB_STATE_SUSPENDED) {
3098                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3099                                 udev->state);
3100                 return -EINVAL;
3101         }
3102
3103         /* Prevent autosuspend during the reset */
3104         usb_autoresume_device(udev);
3105
3106         if (iface && iface->condition != USB_INTERFACE_BINDING)
3107                 iface = NULL;
3108
3109         if (config) {
3110                 int i;
3111                 struct usb_interface *cintf;
3112                 struct usb_driver *drv;
3113
3114                 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
3115                         cintf = config->interface[i];
3116                         if (cintf != iface)
3117                                 down(&cintf->dev.sem);
3118                         if (device_is_registered(&cintf->dev) &&
3119                                         cintf->dev.driver) {
3120                                 drv = to_usb_driver(cintf->dev.driver);
3121                                 if (drv->pre_reset)
3122                                         (drv->pre_reset)(cintf);
3123                         }
3124                 }
3125         }
3126
3127         ret = usb_reset_device(udev);
3128
3129         if (config) {
3130                 int i;
3131                 struct usb_interface *cintf;
3132                 struct usb_driver *drv;
3133
3134                 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
3135                         cintf = config->interface[i];
3136                         if (device_is_registered(&cintf->dev) &&
3137                                         cintf->dev.driver) {
3138                                 drv = to_usb_driver(cintf->dev.driver);
3139                                 if (drv->post_reset)
3140                                         (drv->post_reset)(cintf);
3141                         }
3142                         if (cintf != iface)
3143                                 up(&cintf->dev.sem);
3144                 }
3145         }
3146
3147         usb_autosuspend_device(udev);
3148         return ret;
3149 }
3150 EXPORT_SYMBOL(usb_reset_composite_device);