git.oblomov.eu Git - linux-2.6/blob - 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
  26 #include <asm/semaphore.h>
  27 #include <asm/uaccess.h>
  28 #include <asm/byteorder.h>
  29
  30 #include "usb.h"
  31 #include "hcd.h"
  32 #include "hub.h"
  33
  34 /* Protect struct usb_device->state and ->children members
  35  * Note: Both are also protected by ->dev.sem, except that ->state can
  36  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
  37 static DEFINE_SPINLOCK(device_state_lock);
  38
  39 /* khubd's worklist and its lock */
  40 static DEFINE_SPINLOCK(hub_event_lock);
  41 static LIST_HEAD(hub_event_list);       /* List of hubs needing servicing */
  42
  43 /* Wakes up khubd */
  44 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
  45
  46 static struct task_struct *khubd_task;
  47
  48 /* cycle leds on hubs that aren't blinking for attention */
  49 static int blinkenlights = 0;
  50 module_param (blinkenlights, bool, S_IRUGO);
  51 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
  52
  53 /*
  54  * As of 2.6.10 we introduce a new USB device initialization scheme which
  55  * closely resembles the way Windows works.  Hopefully it will be compatible
  56  * with a wider range of devices than the old scheme.  However some previously
  57  * working devices may start giving rise to "device not accepting address"
  58  * errors; if that happens the user can try the old scheme by adjusting the
  59  * following module parameters.
  60  *
  61  * For maximum flexibility there are two boolean parameters to control the
  62  * hub driver's behavior.  On the first initialization attempt, if the
  63  * "old_scheme_first" parameter is set then the old scheme will be used,
  64  * otherwise the new scheme is used.  If that fails and "use_both_schemes"
  65  * is set, then the driver will make another attempt, using the other scheme.
  66  */
  67 static int old_scheme_first = 0;
  68 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
  69 MODULE_PARM_DESC(old_scheme_first,
  70                  "start with the old device initialization scheme");
  71
  72 static int use_both_schemes = 1;
  73 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
  74 MODULE_PARM_DESC(use_both_schemes,
  75                 "try the other device initialization scheme if the "
  76                 "first one fails");
  77
  78
  79 #ifdef  DEBUG
  80 static inline char *portspeed (int portstatus)
  81 {
  82         if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
  83                 return "480 Mb/s";
  84         else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
  85                 return "1.5 Mb/s";
  86         else
  87                 return "12 Mb/s";
  88 }
  89 #endif
  90
  91 /* Note that hdev or one of its children must be locked! */
  92 static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
  93 {
  94         return usb_get_intfdata(hdev->actconfig->interface[0]);
  95 }
  96
  97 /* USB 2.0 spec Section 11.24.4.5 */
  98 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
  99 {
 100         int i, ret;
 101
 102         for (i = 0; i < 3; i++) {
 103                 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 104                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
 105                         USB_DT_HUB << 8, 0, data, size,
 106                         USB_CTRL_GET_TIMEOUT);
 107                 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
 108                         return ret;
 109         }
 110         return -EINVAL;
 111 }
 112
 113 /*
 114  * USB 2.0 spec Section 11.24.2.1
 115  */
 116 static int clear_hub_feature(struct usb_device *hdev, int feature)
 117 {
 118         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 119                 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
 120 }
 121
 122 /*
 123  * USB 2.0 spec Section 11.24.2.2
 124  */
 125 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
 126 {
 127         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 128                 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
 129                 NULL, 0, 1000);
 130 }
 131
 132 /*
 133  * USB 2.0 spec Section 11.24.2.13
 134  */
 135 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
 136 {
 137         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 138                 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
 139                 NULL, 0, 1000);
 140 }
 141
 142 /*
 143  * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
 144  * for info about using port indicators
 145  */
 146 static void set_port_led(
 147         struct usb_hub *hub,
 148         int port1,
 149         int selector
 150 )
 151 {
 152         int status = set_port_feature(hub->hdev, (selector << 8) | port1,
 153                         USB_PORT_FEAT_INDICATOR);
 154         if (status < 0)
 155                 dev_dbg (hub->intfdev,
 156                         "port %d indicator %s status %d\n",
 157                         port1,
 158                         ({ char *s; switch (selector) {
 159                         case HUB_LED_AMBER: s = "amber"; break;
 160                         case HUB_LED_GREEN: s = "green"; break;
 161                         case HUB_LED_OFF: s = "off"; break;
 162                         case HUB_LED_AUTO: s = "auto"; break;
 163                         default: s = "??"; break;
 164                         }; s; }),
 165                         status);
 166 }
 167
 168 #define LED_CYCLE_PERIOD        ((2*HZ)/3)
 169
 170 static void led_work (void *__hub)
 171 {
 172         struct usb_hub          *hub = __hub;
 173         struct usb_device       *hdev = hub->hdev;
 174         unsigned                i;
 175         unsigned                changed = 0;
 176         int                     cursor = -1;
 177
 178         if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
 179                 return;
 180
 181         for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
 182                 unsigned        selector, mode;
 183
 184                 /* 30%-50% duty cycle */
 185
 186                 switch (hub->indicator[i]) {
 187                 /* cycle marker */
 188                 case INDICATOR_CYCLE:
 189                         cursor = i;
 190                         selector = HUB_LED_AUTO;
 191                         mode = INDICATOR_AUTO;
 192                         break;
 193                 /* blinking green = sw attention */
 194                 case INDICATOR_GREEN_BLINK:
 195                         selector = HUB_LED_GREEN;
 196                         mode = INDICATOR_GREEN_BLINK_OFF;
 197                         break;
 198                 case INDICATOR_GREEN_BLINK_OFF:
 199                         selector = HUB_LED_OFF;
 200                         mode = INDICATOR_GREEN_BLINK;
 201                         break;
 202                 /* blinking amber = hw attention */
 203                 case INDICATOR_AMBER_BLINK:
 204                         selector = HUB_LED_AMBER;
 205                         mode = INDICATOR_AMBER_BLINK_OFF;
 206                         break;
 207                 case INDICATOR_AMBER_BLINK_OFF:
 208                         selector = HUB_LED_OFF;
 209                         mode = INDICATOR_AMBER_BLINK;
 210                         break;
 211                 /* blink green/amber = reserved */
 212                 case INDICATOR_ALT_BLINK:
 213                         selector = HUB_LED_GREEN;
 214                         mode = INDICATOR_ALT_BLINK_OFF;
 215                         break;
 216                 case INDICATOR_ALT_BLINK_OFF:
 217                         selector = HUB_LED_AMBER;
 218                         mode = INDICATOR_ALT_BLINK;
 219                         break;
 220                 default:
 221                         continue;
 222                 }
 223                 if (selector != HUB_LED_AUTO)
 224                         changed = 1;
 225                 set_port_led(hub, i + 1, selector);
 226                 hub->indicator[i] = mode;
 227         }
 228         if (!changed && blinkenlights) {
 229                 cursor++;
 230                 cursor %= hub->descriptor->bNbrPorts;
 231                 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
 232                 hub->indicator[cursor] = INDICATOR_CYCLE;
 233                 changed++;
 234         }
 235         if (changed)
 236                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 237 }
 238
 239 /* use a short timeout for hub/port status fetches */
 240 #define USB_STS_TIMEOUT         1000
 241 #define USB_STS_RETRIES         5
 242
 243 /*
 244  * USB 2.0 spec Section 11.24.2.6
 245  */
 246 static int get_hub_status(struct usb_device *hdev,
 247                 struct usb_hub_status *data)
 248 {
 249         int i, status = -ETIMEDOUT;
 250
 251         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
 252                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 253                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
 254                         data, sizeof(*data), USB_STS_TIMEOUT);
 255         }
 256         return status;
 257 }
 258
 259 /*
 260  * USB 2.0 spec Section 11.24.2.7
 261  */
 262 static int get_port_status(struct usb_device *hdev, int port1,
 263                 struct usb_port_status *data)
 264 {
 265         int i, status = -ETIMEDOUT;
 266
 267         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
 268                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 269                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
 270                         data, sizeof(*data), USB_STS_TIMEOUT);
 271         }
 272         return status;
 273 }
 274
 275 static void kick_khubd(struct usb_hub *hub)
 276 {
 277         unsigned long   flags;
 278
 279         spin_lock_irqsave(&hub_event_lock, flags);
 280         if (list_empty(&hub->event_list)) {
 281                 list_add_tail(&hub->event_list, &hub_event_list);
 282                 wake_up(&khubd_wait);
 283         }
 284         spin_unlock_irqrestore(&hub_event_lock, flags);
 285 }
 286
 287 void usb_kick_khubd(struct usb_device *hdev)
 288 {
 289         kick_khubd(hdev_to_hub(hdev));
 290 }
 291
 292
 293 /* completion function, fires on port status changes and various faults */
 294 static void hub_irq(struct urb *urb, struct pt_regs *regs)
 295 {
 296         struct usb_hub *hub = (struct usb_hub *)urb->context;
 297         int status;
 298         int i;
 299         unsigned long bits;
 300
 301         switch (urb->status) {
 302         case -ENOENT:           /* synchronous unlink */
 303         case -ECONNRESET:       /* async unlink */
 304         case -ESHUTDOWN:        /* hardware going away */
 305                 return;
 306
 307         default:                /* presumably an error */
 308                 /* Cause a hub reset after 10 consecutive errors */
 309                 dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
 310                 if ((++hub->nerrors < 10) || hub->error)
 311                         goto resubmit;
 312                 hub->error = urb->status;
 313                 /* FALL THROUGH */
 314
 315         /* let khubd handle things */
 316         case 0:                 /* we got data:  port status changed */
 317                 bits = 0;
 318                 for (i = 0; i < urb->actual_length; ++i)
 319                         bits |= ((unsigned long) ((*hub->buffer)[i]))
 320                                         << (i*8);
 321                 hub->event_bits[0] = bits;
 322                 break;
 323         }
 324
 325         hub->nerrors = 0;
 326
 327         /* Something happened, let khubd figure it out */
 328         kick_khubd(hub);
 329
 330 resubmit:
 331         if (hub->quiescing)
 332                 return;
 333
 334         if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
 335                         && status != -ENODEV && status != -EPERM)
 336                 dev_err (hub->intfdev, "resubmit --> %d\n", status);
 337 }
 338
 339 /* USB 2.0 spec Section 11.24.2.3 */
 340 static inline int
 341 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
 342 {
 343         return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 344                                HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
 345                                tt, NULL, 0, 1000);
 346 }
 347
 348 /*
 349  * enumeration blocks khubd for a long time. we use keventd instead, since
 350  * long blocking there is the exception, not the rule.  accordingly, HCDs
 351  * talking to TTs must queue control transfers (not just bulk and iso), so
 352  * both can talk to the same hub concurrently.
 353  */
 354 static void hub_tt_kevent (void *arg)
 355 {
 356         struct usb_hub          *hub = arg;
 357         unsigned long           flags;
 358
 359         spin_lock_irqsave (&hub->tt.lock, flags);
 360         while (!list_empty (&hub->tt.clear_list)) {
 361                 struct list_head        *temp;
 362                 struct usb_tt_clear     *clear;
 363                 struct usb_device       *hdev = hub->hdev;
 364                 int                     status;
 365
 366                 temp = hub->tt.clear_list.next;
 367                 clear = list_entry (temp, struct usb_tt_clear, clear_list);
 368                 list_del (&clear->clear_list);
 369
 370                 /* drop lock so HCD can concurrently report other TT errors */
 371                 spin_unlock_irqrestore (&hub->tt.lock, flags);
 372                 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
 373                 spin_lock_irqsave (&hub->tt.lock, flags);
 374
 375                 if (status)
 376                         dev_err (&hdev->dev,
 377                                 "clear tt %d (%04x) error %d\n",
 378                                 clear->tt, clear->devinfo, status);
 379                 kfree(clear);
 380         }
 381         spin_unlock_irqrestore (&hub->tt.lock, flags);
 382 }
 383
 384 /**
 385  * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
 386  * @udev: the device whose split transaction failed
 387  * @pipe: identifies the endpoint of the failed transaction
 388  *
 389  * High speed HCDs use this to tell the hub driver that some split control or
 390  * bulk transaction failed in a way that requires clearing internal state of
 391  * a transaction translator.  This is normally detected (and reported) from
 392  * interrupt context.
 393  *
 394  * It may not be possible for that hub to handle additional full (or low)
 395  * speed transactions until that state is fully cleared out.
 396  */
 397 void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
 398 {
 399         struct usb_tt           *tt = udev->tt;
 400         unsigned long           flags;
 401         struct usb_tt_clear     *clear;
 402
 403         /* we've got to cope with an arbitrary number of pending TT clears,
 404          * since each TT has "at least two" buffers that can need it (and
 405          * there can be many TTs per hub).  even if they're uncommon.
 406          */
 407         if ((clear = kmalloc (sizeof *clear, SLAB_ATOMIC)) == NULL) {
 408                 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
 409                 /* FIXME recover somehow ... RESET_TT? */
 410                 return;
 411         }
 412
 413         /* info that CLEAR_TT_BUFFER needs */
 414         clear->tt = tt->multi ? udev->ttport : 1;
 415         clear->devinfo = usb_pipeendpoint (pipe);
 416         clear->devinfo |= udev->devnum << 4;
 417         clear->devinfo |= usb_pipecontrol (pipe)
 418                         ? (USB_ENDPOINT_XFER_CONTROL << 11)
 419                         : (USB_ENDPOINT_XFER_BULK << 11);
 420         if (usb_pipein (pipe))
 421                 clear->devinfo |= 1 << 15;
 422
 423         /* tell keventd to clear state for this TT */
 424         spin_lock_irqsave (&tt->lock, flags);
 425         list_add_tail (&clear->clear_list, &tt->clear_list);
 426         schedule_work (&tt->kevent);
 427         spin_unlock_irqrestore (&tt->lock, flags);
 428 }
 429
 430 static void hub_power_on(struct usb_hub *hub)
 431 {
 432         int port1;
 433         unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
 434         u16 wHubCharacteristics =
 435                         le16_to_cpu(hub->descriptor->wHubCharacteristics);
 436
 437         /* Enable power on each port.  Some hubs have reserved values
 438          * of LPSM (> 2) in their descriptors, even though they are
 439          * USB 2.0 hubs.  Some hubs do not implement port-power switching
 440          * but only emulate it.  In all cases, the ports won't work
 441          * unless we send these messages to the hub.
 442          */
 443         if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
 444                 dev_dbg(hub->intfdev, "enabling power on all ports\n");
 445         else
 446                 dev_dbg(hub->intfdev, "trying to enable port power on "
 447                                 "non-switchable hub\n");
 448         for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
 449                 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
 450
 451         /* Wait at least 100 msec for power to become stable */
 452         msleep(max(pgood_delay, (unsigned) 100));
 453 }
 454
 455 static inline void __hub_quiesce(struct usb_hub *hub)
 456 {
 457         /* (nonblocking) khubd and related activity won't re-trigger */
 458         hub->quiescing = 1;
 459         hub->activating = 0;
 460         hub->resume_root_hub = 0;
 461 }
 462
 463 static void hub_quiesce(struct usb_hub *hub)
 464 {
 465         /* (blocking) stop khubd and related activity */
 466         __hub_quiesce(hub);
 467         usb_kill_urb(hub->urb);
 468         if (hub->has_indicators)
 469                 cancel_delayed_work(&hub->leds);
 470         if (hub->has_indicators || hub->tt.hub)
 471                 flush_scheduled_work();
 472 }
 473
 474 static void hub_activate(struct usb_hub *hub)
 475 {
 476         int     status;
 477
 478         hub->quiescing = 0;
 479         hub->activating = 1;
 480         hub->resume_root_hub = 0;
 481         status = usb_submit_urb(hub->urb, GFP_NOIO);
 482         if (status < 0)
 483                 dev_err(hub->intfdev, "activate --> %d\n", status);
 484         if (hub->has_indicators && blinkenlights)
 485                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 486
 487         /* scan all ports ASAP */
 488         kick_khubd(hub);
 489 }
 490
 491 static int hub_hub_status(struct usb_hub *hub,
 492                 u16 *status, u16 *change)
 493 {
 494         int ret;
 495
 496         ret = get_hub_status(hub->hdev, &hub->status->hub);
 497         if (ret < 0)
 498                 dev_err (hub->intfdev,
 499                         "%s failed (err = %d)\n", __FUNCTION__, ret);
 500         else {
 501                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
 502                 *change = le16_to_cpu(hub->status->hub.wHubChange);
 503                 ret = 0;
 504         }
 505         return ret;
 506 }
 507
 508 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
 509 {
 510         struct usb_device *hdev = hub->hdev;
 511         int ret;
 512
 513         if (hdev->children[port1-1] && set_state) {
 514                 usb_set_device_state(hdev->children[port1-1],
 515                                 USB_STATE_NOTATTACHED);
 516         }
 517         ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
 518         if (ret)
 519                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
 520                         port1, ret);
 521
 522         return ret;
 523 }
 524
 525
 526 /* caller has locked the hub device */
 527 static void hub_pre_reset(struct usb_interface *intf)
 528 {
 529         struct usb_hub *hub = usb_get_intfdata(intf);
 530         struct usb_device *hdev = hub->hdev;
 531         int port1;
 532
 533         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
 534                 if (hdev->children[port1 - 1]) {
 535                         usb_disconnect(&hdev->children[port1 - 1]);
 536                         if (hub->error == 0)
 537                                 hub_port_disable(hub, port1, 0);
 538                 }
 539         }
 540         hub_quiesce(hub);
 541 }
 542
 543 /* caller has locked the hub device */
 544 static void hub_post_reset(struct usb_interface *intf)
 545 {
 546         struct usb_hub *hub = usb_get_intfdata(intf);
 547
 548         hub_activate(hub);
 549         hub_power_on(hub);
 550 }
 551
 552
 553 static int hub_configure(struct usb_hub *hub,
 554         struct usb_endpoint_descriptor *endpoint)
 555 {
 556         struct usb_device *hdev = hub->hdev;
 557         struct device *hub_dev = hub->intfdev;
 558         u16 hubstatus, hubchange;
 559         u16 wHubCharacteristics;
 560         unsigned int pipe;
 561         int maxp, ret;
 562         char *message;
 563
 564         hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
 565                         &hub->buffer_dma);
 566         if (!hub->buffer) {
 567                 message = "can't allocate hub irq buffer";
 568                 ret = -ENOMEM;
 569                 goto fail;
 570         }
 571
 572         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
 573         if (!hub->status) {
 574                 message = "can't kmalloc hub status buffer";
 575                 ret = -ENOMEM;
 576                 goto fail;
 577         }
 578
 579         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
 580         if (!hub->descriptor) {
 581                 message = "can't kmalloc hub descriptor";
 582                 ret = -ENOMEM;
 583                 goto fail;
 584         }
 585
 586         /* Request the entire hub descriptor.
 587          * hub->descriptor can handle USB_MAXCHILDREN ports,
 588          * but the hub can/will return fewer bytes here.
 589          */
 590         ret = get_hub_descriptor(hdev, hub->descriptor,
 591                         sizeof(*hub->descriptor));
 592         if (ret < 0) {
 593                 message = "can't read hub descriptor";
 594                 goto fail;
 595         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
 596                 message = "hub has too many ports!";
 597                 ret = -ENODEV;
 598                 goto fail;
 599         }
 600
 601         hdev->maxchild = hub->descriptor->bNbrPorts;
 602         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
 603                 (hdev->maxchild == 1) ? "" : "s");
 604
 605         wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
 606
 607         if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
 608                 int     i;
 609                 char    portstr [USB_MAXCHILDREN + 1];
 610
 611                 for (i = 0; i < hdev->maxchild; i++)
 612                         portstr[i] = hub->descriptor->DeviceRemovable
 613                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
 614                                 ? 'F' : 'R';
 615                 portstr[hdev->maxchild] = 0;
 616                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
 617         } else
 618                 dev_dbg(hub_dev, "standalone hub\n");
 619
 620         switch (wHubCharacteristics & HUB_CHAR_LPSM) {
 621                 case 0x00:
 622                         dev_dbg(hub_dev, "ganged power switching\n");
 623                         break;
 624                 case 0x01:
 625                         dev_dbg(hub_dev, "individual port power switching\n");
 626                         break;
 627                 case 0x02:
 628                 case 0x03:
 629                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
 630                         break;
 631         }
 632
 633         switch (wHubCharacteristics & HUB_CHAR_OCPM) {
 634                 case 0x00:
 635                         dev_dbg(hub_dev, "global over-current protection\n");
 636                         break;
 637                 case 0x08:
 638                         dev_dbg(hub_dev, "individual port over-current protection\n");
 639                         break;
 640                 case 0x10:
 641                 case 0x18:
 642                         dev_dbg(hub_dev, "no over-current protection\n");
 643                         break;
 644         }
 645
 646         spin_lock_init (&hub->tt.lock);
 647         INIT_LIST_HEAD (&hub->tt.clear_list);
 648         INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub);
 649         switch (hdev->descriptor.bDeviceProtocol) {
 650                 case 0:
 651                         break;
 652                 case 1:
 653                         dev_dbg(hub_dev, "Single TT\n");
 654                         hub->tt.hub = hdev;
 655                         break;
 656                 case 2:
 657                         ret = usb_set_interface(hdev, 0, 1);
 658                         if (ret == 0) {
 659                                 dev_dbg(hub_dev, "TT per port\n");
 660                                 hub->tt.multi = 1;
 661                         } else
 662                                 dev_err(hub_dev, "Using single TT (err %d)\n",
 663                                         ret);
 664                         hub->tt.hub = hdev;
 665                         break;
 666                 default:
 667                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
 668                                 hdev->descriptor.bDeviceProtocol);
 669                         break;
 670         }
 671
 672         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
 673         switch (wHubCharacteristics & HUB_CHAR_TTTT) {
 674                 case HUB_TTTT_8_BITS:
 675                         if (hdev->descriptor.bDeviceProtocol != 0) {
 676                                 hub->tt.think_time = 666;
 677                                 dev_dbg(hub_dev, "TT requires at most %d "
 678                                                 "FS bit times (%d ns)\n",
 679                                         8, hub->tt.think_time);
 680                         }
 681                         break;
 682                 case HUB_TTTT_16_BITS:
 683                         hub->tt.think_time = 666 * 2;
 684                         dev_dbg(hub_dev, "TT requires at most %d "
 685                                         "FS bit times (%d ns)\n",
 686                                 16, hub->tt.think_time);
 687                         break;
 688                 case HUB_TTTT_24_BITS:
 689                         hub->tt.think_time = 666 * 3;
 690                         dev_dbg(hub_dev, "TT requires at most %d "
 691                                         "FS bit times (%d ns)\n",
 692                                 24, hub->tt.think_time);
 693                         break;
 694                 case HUB_TTTT_32_BITS:
 695                         hub->tt.think_time = 666 * 4;
 696                         dev_dbg(hub_dev, "TT requires at most %d "
 697                                         "FS bit times (%d ns)\n",
 698                                 32, hub->tt.think_time);
 699                         break;
 700         }
 701
 702         /* probe() zeroes hub->indicator[] */
 703         if (wHubCharacteristics & HUB_CHAR_PORTIND) {
 704                 hub->has_indicators = 1;
 705                 dev_dbg(hub_dev, "Port indicators are supported\n");
 706         }
 707
 708         dev_dbg(hub_dev, "power on to power good time: %dms\n",
 709                 hub->descriptor->bPwrOn2PwrGood * 2);
 710
 711         /* power budgeting mostly matters with bus-powered hubs,
 712          * and battery-powered root hubs (may provide just 8 mA).
 713          */
 714         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
 715         if (ret < 2) {
 716                 message = "can't get hub status";
 717                 goto fail;
 718         }
 719         le16_to_cpus(&hubstatus);
 720         if (hdev == hdev->bus->root_hub) {
 721                 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
 722                         hub->mA_per_port = 500;
 723                 else {
 724                         hub->mA_per_port = hdev->bus_mA;
 725                         hub->limited_power = 1;
 726                 }
 727         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
 728                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
 729                         hub->descriptor->bHubContrCurrent);
 730                 hub->limited_power = 1;
 731                 if (hdev->maxchild > 0) {
 732                         int remaining = hdev->bus_mA -
 733                                         hub->descriptor->bHubContrCurrent;
 734
 735                         if (remaining < hdev->maxchild * 100)
 736                                 dev_warn(hub_dev,
 737                                         "insufficient power available "
 738                                         "to use all downstream ports\n");
 739                         hub->mA_per_port = 100;         /* 7.2.1.1 */
 740                 }
 741         } else {        /* Self-powered external hub */
 742                 /* FIXME: What about battery-powered external hubs that
 743                  * provide less current per port? */
 744                 hub->mA_per_port = 500;
 745         }
 746         if (hub->mA_per_port < 500)
 747                 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
 748                                 hub->mA_per_port);
 749
 750         ret = hub_hub_status(hub, &hubstatus, &hubchange);
 751         if (ret < 0) {
 752                 message = "can't get hub status";
 753                 goto fail;
 754         }
 755
 756         /* local power status reports aren't always correct */
 757         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
 758                 dev_dbg(hub_dev, "local power source is %s\n",
 759                         (hubstatus & HUB_STATUS_LOCAL_POWER)
 760                         ? "lost (inactive)" : "good");
 761
 762         if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
 763                 dev_dbg(hub_dev, "%sover-current condition exists\n",
 764                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
 765
 766         /* set up the interrupt endpoint */
 767         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
 768         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
 769
 770         if (maxp > sizeof(*hub->buffer))
 771                 maxp = sizeof(*hub->buffer);
 772
 773         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
 774         if (!hub->urb) {
 775                 message = "couldn't allocate interrupt urb";
 776                 ret = -ENOMEM;
 777                 goto fail;
 778         }
 779
 780         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
 781                 hub, endpoint->bInterval);
 782         hub->urb->transfer_dma = hub->buffer_dma;
 783         hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 784
 785         /* maybe cycle the hub leds */
 786         if (hub->has_indicators && blinkenlights)
 787                 hub->indicator [0] = INDICATOR_CYCLE;
 788
 789         hub_power_on(hub);
 790         hub_activate(hub);
 791         return 0;
 792
 793 fail:
 794         dev_err (hub_dev, "config failed, %s (err %d)\n",
 795                         message, ret);
 796         /* hub_disconnect() frees urb and descriptor */
 797         return ret;
 798 }
 799
 800 static unsigned highspeed_hubs;
 801
 802 static void hub_disconnect(struct usb_interface *intf)
 803 {
 804         struct usb_hub *hub = usb_get_intfdata (intf);
 805         struct usb_device *hdev;
 806
 807         /* Disconnect all children and quiesce the hub */
 808         hub->error = 0;
 809         hub_pre_reset(intf);
 810
 811         usb_set_intfdata (intf, NULL);
 812         hdev = hub->hdev;
 813
 814         if (hdev->speed == USB_SPEED_HIGH)
 815                 highspeed_hubs--;
 816
 817         usb_free_urb(hub->urb);
 818         hub->urb = NULL;
 819
 820         spin_lock_irq(&hub_event_lock);
 821         list_del_init(&hub->event_list);
 822         spin_unlock_irq(&hub_event_lock);
 823
 824         kfree(hub->descriptor);
 825         hub->descriptor = NULL;
 826
 827         kfree(hub->status);
 828         hub->status = NULL;
 829
 830         if (hub->buffer) {
 831                 usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
 832                                 hub->buffer_dma);
 833                 hub->buffer = NULL;
 834         }
 835
 836         kfree(hub);
 837 }
 838
 839 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
 840 {
 841         struct usb_host_interface *desc;
 842         struct usb_endpoint_descriptor *endpoint;
 843         struct usb_device *hdev;
 844         struct usb_hub *hub;
 845
 846         desc = intf->cur_altsetting;
 847         hdev = interface_to_usbdev(intf);
 848
 849 #ifdef  CONFIG_USB_OTG_BLACKLIST_HUB
 850         if (hdev->parent) {
 851                 dev_warn(&intf->dev, "ignoring external hub\n");
 852                 return -ENODEV;
 853         }
 854 #endif
 855
 856         /* Some hubs have a subclass of 1, which AFAICT according to the */
 857         /*  specs is not defined, but it works */
 858         if ((desc->desc.bInterfaceSubClass != 0) &&
 859             (desc->desc.bInterfaceSubClass != 1)) {
 860 descriptor_error:
 861                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
 862                 return -EIO;
 863         }
 864
 865         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
 866         if (desc->desc.bNumEndpoints != 1)
 867                 goto descriptor_error;
 868
 869         endpoint = &desc->endpoint[0].desc;
 870
 871         /* Output endpoint? Curiouser and curiouser.. */
 872         if (!(endpoint->bEndpointAddress & USB_DIR_IN))
 873                 goto descriptor_error;
 874
 875         /* If it's not an interrupt endpoint, we'd better punt! */
 876         if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
 877                         != USB_ENDPOINT_XFER_INT)
 878                 goto descriptor_error;
 879
 880         /* We found a hub */
 881         dev_info (&intf->dev, "USB hub found\n");
 882
 883         hub = kzalloc(sizeof(*hub), GFP_KERNEL);
 884         if (!hub) {
 885                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
 886                 return -ENOMEM;
 887         }
 888
 889         INIT_LIST_HEAD(&hub->event_list);
 890         hub->intfdev = &intf->dev;
 891         hub->hdev = hdev;
 892         INIT_WORK(&hub->leds, led_work, hub);
 893
 894         usb_set_intfdata (intf, hub);
 895
 896         if (hdev->speed == USB_SPEED_HIGH)
 897                 highspeed_hubs++;
 898
 899         if (hub_configure(hub, endpoint) >= 0)
 900                 return 0;
 901
 902         hub_disconnect (intf);
 903         return -ENODEV;
 904 }
 905
 906 static int
 907 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
 908 {
 909         struct usb_device *hdev = interface_to_usbdev (intf);
 910
 911         /* assert ifno == 0 (part of hub spec) */
 912         switch (code) {
 913         case USBDEVFS_HUB_PORTINFO: {
 914                 struct usbdevfs_hub_portinfo *info = user_data;
 915                 int i;
 916
 917                 spin_lock_irq(&device_state_lock);
 918                 if (hdev->devnum <= 0)
 919                         info->nports = 0;
 920                 else {
 921                         info->nports = hdev->maxchild;
 922                         for (i = 0; i < info->nports; i++) {
 923                                 if (hdev->children[i] == NULL)
 924                                         info->port[i] = 0;
 925                                 else
 926                                         info->port[i] =
 927                                                 hdev->children[i]->devnum;
 928                         }
 929                 }
 930                 spin_unlock_irq(&device_state_lock);
 931
 932                 return info->nports + 1;
 933                 }
 934
 935         default:
 936                 return -ENOSYS;
 937         }
 938 }
 939
 940
 941 /* grab device/port lock, returning index of that port (zero based).
 942  * protects the upstream link used by this device from concurrent
 943  * tree operations like suspend, resume, reset, and disconnect, which
 944  * apply to everything downstream of a given port.
 945  */
 946 static int locktree(struct usb_device *udev)
 947 {
 948         int                     t;
 949         struct usb_device       *hdev;
 950
 951         if (!udev)
 952                 return -ENODEV;
 953
 954         /* root hub is always the first lock in the series */
 955         hdev = udev->parent;
 956         if (!hdev) {
 957                 usb_lock_device(udev);
 958                 return 0;
 959         }
 960
 961         /* on the path from root to us, lock everything from
 962          * top down, dropping parent locks when not needed
 963          */
 964         t = locktree(hdev);
 965         if (t < 0)
 966                 return t;
 967
 968         /* everything is fail-fast once disconnect
 969          * processing starts
 970          */
 971         if (udev->state == USB_STATE_NOTATTACHED) {
 972                 usb_unlock_device(hdev);
 973                 return -ENODEV;
 974         }
 975
 976         /* when everyone grabs locks top->bottom,
 977          * non-overlapping work may be concurrent
 978          */
 979         usb_lock_device(udev);
 980         usb_unlock_device(hdev);
 981         return udev->portnum;
 982 }
 983
 984 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
 985 {
 986         int i;
 987
 988         for (i = 0; i < udev->maxchild; ++i) {
 989                 if (udev->children[i])
 990                         recursively_mark_NOTATTACHED(udev->children[i]);
 991         }
 992         udev->state = USB_STATE_NOTATTACHED;
 993 }
 994
 995 /**
 996  * usb_set_device_state - change a device's current state (usbcore, hcds)
 997  * @udev: pointer to device whose state should be changed
 998  * @new_state: new state value to be stored
 999  *
1000  * udev->state is _not_ fully protected by the device lock.  Although
1001  * most transitions are made only while holding the lock, the state can
1002  * can change to USB_STATE_NOTATTACHED at almost any time.  This
1003  * is so that devices can be marked as disconnected as soon as possible,
1004  * without having to wait for any semaphores to be released.  As a result,
1005  * all changes to any device's state must be protected by the
1006  * device_state_lock spinlock.
1007  *
1008  * Once a device has been added to the device tree, all changes to its state
1009  * should be made using this routine.  The state should _not_ be set directly.
1010  *
1011  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1012  * Otherwise udev->state is set to new_state, and if new_state is
1013  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1014  * to USB_STATE_NOTATTACHED.
1015  */
1016 void usb_set_device_state(struct usb_device *udev,
1017                 enum usb_device_state new_state)
1018 {
1019         unsigned long flags;
1020
1021         spin_lock_irqsave(&device_state_lock, flags);
1022         if (udev->state == USB_STATE_NOTATTACHED)
1023                 ;       /* do nothing */
1024         else if (new_state != USB_STATE_NOTATTACHED) {
1025                 udev->state = new_state;
1026
1027                 /* root hub wakeup capabilities are managed out-of-band
1028                  * and may involve silicon errata ... ignore them here.
1029                  */
1030                 if (udev->parent) {
1031                         if (new_state == USB_STATE_CONFIGURED)
1032                                 device_init_wakeup(&udev->dev,
1033                                         (udev->actconfig->desc.bmAttributes
1034                                          & USB_CONFIG_ATT_WAKEUP));
1035                         else if (new_state != USB_STATE_SUSPENDED)
1036                                 device_init_wakeup(&udev->dev, 0);
1037                 }
1038         } else
1039                 recursively_mark_NOTATTACHED(udev);
1040         spin_unlock_irqrestore(&device_state_lock, flags);
1041 }
1042
1043
1044 #ifdef CONFIG_PM
1045
1046 /**
1047  * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
1048  * @rhdev: struct usb_device for the root hub
1049  *
1050  * The USB host controller driver calls this function when its root hub
1051  * is resumed and Vbus power has been interrupted or the controller
1052  * has been reset.  The routine marks all the children of the root hub
1053  * as NOTATTACHED and marks logical connect-change events on their ports.
1054  */
1055 void usb_root_hub_lost_power(struct usb_device *rhdev)
1056 {
1057         struct usb_hub *hub;
1058         int port1;
1059         unsigned long flags;
1060
1061         dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
1062         spin_lock_irqsave(&device_state_lock, flags);
1063         hub = hdev_to_hub(rhdev);
1064         for (port1 = 1; port1 <= rhdev->maxchild; ++port1) {
1065                 if (rhdev->children[port1 - 1]) {
1066                         recursively_mark_NOTATTACHED(
1067                                         rhdev->children[port1 - 1]);
1068                         set_bit(port1, hub->change_bits);
1069                 }
1070         }
1071         spin_unlock_irqrestore(&device_state_lock, flags);
1072 }
1073 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
1074
1075 #endif
1076
1077 static void choose_address(struct usb_device *udev)
1078 {
1079         int             devnum;
1080         struct usb_bus  *bus = udev->bus;
1081
1082         /* If khubd ever becomes multithreaded, this will need a lock */
1083
1084         /* Try to allocate the next devnum beginning at bus->devnum_next. */
1085         devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1086                         bus->devnum_next);
1087         if (devnum >= 128)
1088                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1089
1090         bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1091
1092         if (devnum < 128) {
1093                 set_bit(devnum, bus->devmap.devicemap);
1094                 udev->devnum = devnum;
1095         }
1096 }
1097
1098 static void release_address(struct usb_device *udev)
1099 {
1100         if (udev->devnum > 0) {
1101                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1102                 udev->devnum = -1;
1103         }
1104 }
1105
1106 /**
1107  * usb_disconnect - disconnect a device (usbcore-internal)
1108  * @pdev: pointer to device being disconnected
1109  * Context: !in_interrupt ()
1110  *
1111  * Something got disconnected. Get rid of it and all of its children.
1112  *
1113  * If *pdev is a normal device then the parent hub must already be locked.
1114  * If *pdev is a root hub then this routine will acquire the
1115  * usb_bus_list_lock on behalf of the caller.
1116  *
1117  * Only hub drivers (including virtual root hub drivers for host
1118  * controllers) should ever call this.
1119  *
1120  * This call is synchronous, and may not be used in an interrupt context.
1121  */
1122 void usb_disconnect(struct usb_device **pdev)
1123 {
1124         struct usb_device       *udev = *pdev;
1125         int                     i;
1126
1127         if (!udev) {
1128                 pr_debug ("%s nodev\n", __FUNCTION__);
1129                 return;
1130         }
1131
1132         /* mark the device as inactive, so any further urb submissions for
1133          * this device (and any of its children) will fail immediately.
1134          * this quiesces everyting except pending urbs.
1135          */
1136         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1137         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1138
1139         usb_lock_device(udev);
1140
1141         /* Free up all the children before we remove this device */
1142         for (i = 0; i < USB_MAXCHILDREN; i++) {
1143                 if (udev->children[i])
1144                         usb_disconnect(&udev->children[i]);
1145         }
1146
1147         /* deallocate hcd/hardware state ... nuking all pending urbs and
1148          * cleaning up all state associated with the current configuration
1149          * so that the hardware is now fully quiesced.
1150          */
1151         usb_disable_device(udev, 0);
1152
1153         usb_notify_remove_device(udev);
1154
1155         /* Free the device number, remove the /proc/bus/usb entry and
1156          * the sysfs attributes, and delete the parent's children[]
1157          * (or root_hub) pointer.
1158          */
1159         dev_dbg (&udev->dev, "unregistering device\n");
1160         release_address(udev);
1161         usb_remove_sysfs_dev_files(udev);
1162
1163         /* Avoid races with recursively_mark_NOTATTACHED() */
1164         spin_lock_irq(&device_state_lock);
1165         *pdev = NULL;
1166         spin_unlock_irq(&device_state_lock);
1167
1168         usb_unlock_device(udev);
1169
1170         device_unregister(&udev->dev);
1171 }
1172
1173 static inline const char *plural(int n)
1174 {
1175         return (n == 1 ? "" : "s");
1176 }
1177
1178 static int choose_configuration(struct usb_device *udev)
1179 {
1180         int i;
1181         int num_configs;
1182         int insufficient_power = 0;
1183         struct usb_host_config *c, *best;
1184
1185         best = NULL;
1186         c = udev->config;
1187         num_configs = udev->descriptor.bNumConfigurations;
1188         for (i = 0; i < num_configs; (i++, c++)) {
1189                 struct usb_interface_descriptor *desc = NULL;
1190
1191                 /* It's possible that a config has no interfaces! */
1192                 if (c->desc.bNumInterfaces > 0)
1193                         desc = &c->intf_cache[0]->altsetting->desc;
1194
1195                 /*
1196                  * HP's USB bus-powered keyboard has only one configuration
1197                  * and it claims to be self-powered; other devices may have
1198                  * similar errors in their descriptors.  If the next test
1199                  * were allowed to execute, such configurations would always
1200                  * be rejected and the devices would not work as expected.
1201                  * In the meantime, we run the risk of selecting a config
1202                  * that requires external power at a time when that power
1203                  * isn't available.  It seems to be the lesser of two evils.
1204                  *
1205                  * Bugzilla #6448 reports a device that appears to crash
1206                  * when it receives a GET_DEVICE_STATUS request!  We don't
1207                  * have any other way to tell whether a device is self-powered,
1208                  * but since we don't use that information anywhere but here,
1209                  * the call has been removed.
1210                  *
1211                  * Maybe the GET_DEVICE_STATUS call and the test below can
1212                  * be reinstated when device firmwares become more reliable.
1213                  * Don't hold your breath.
1214                  */
1215 #if 0
1216                 /* Rule out self-powered configs for a bus-powered device */
1217                 if (bus_powered && (c->desc.bmAttributes &
1218                                         USB_CONFIG_ATT_SELFPOWER))
1219                         continue;
1220 #endif
1221
1222                 /*
1223                  * The next test may not be as effective as it should be.
1224                  * Some hubs have errors in their descriptor, claiming
1225                  * to be self-powered when they are really bus-powered.
1226                  * We will overestimate the amount of current such hubs
1227                  * make available for each port.
1228                  *
1229                  * This is a fairly benign sort of failure.  It won't
1230                  * cause us to reject configurations that we should have
1231                  * accepted.
1232                  */
1233
1234                 /* Rule out configs that draw too much bus current */
1235                 if (c->desc.bMaxPower * 2 > udev->bus_mA) {
1236                         insufficient_power++;
1237                         continue;
1238                 }
1239
1240                 /* If the first config's first interface is COMM/2/0xff
1241                  * (MSFT RNDIS), rule it out unless Linux has host-side
1242                  * RNDIS support. */
1243                 if (i == 0 && desc
1244                                 && desc->bInterfaceClass == USB_CLASS_COMM
1245                                 && desc->bInterfaceSubClass == 2
1246                                 && desc->bInterfaceProtocol == 0xff) {
1247 #ifndef CONFIG_USB_NET_RNDIS_HOST
1248                         continue;
1249 #else
1250                         best = c;
1251 #endif
1252                 }
1253
1254                 /* From the remaining configs, choose the first one whose
1255                  * first interface is for a non-vendor-specific class.
1256                  * Reason: Linux is more likely to have a class driver
1257                  * than a vendor-specific driver. */
1258                 else if (udev->descriptor.bDeviceClass !=
1259                                                 USB_CLASS_VENDOR_SPEC &&
1260                                 (!desc || desc->bInterfaceClass !=
1261                                                 USB_CLASS_VENDOR_SPEC)) {
1262                         best = c;
1263                         break;
1264                 }
1265
1266                 /* If all the remaining configs are vendor-specific,
1267                  * choose the first one. */
1268                 else if (!best)
1269                         best = c;
1270         }
1271
1272         if (insufficient_power > 0)
1273                 dev_info(&udev->dev, "rejected %d configuration%s "
1274                         "due to insufficient available bus power\n",
1275                         insufficient_power, plural(insufficient_power));
1276
1277         if (best) {
1278                 i = best->desc.bConfigurationValue;
1279                 dev_info(&udev->dev,
1280                         "configuration #%d chosen from %d choice%s\n",
1281                         i, num_configs, plural(num_configs));
1282         } else {
1283                 i = -1;
1284                 dev_warn(&udev->dev,
1285                         "no configuration chosen from %d choice%s\n",
1286                         num_configs, plural(num_configs));
1287         }
1288         return i;
1289 }
1290
1291 #ifdef DEBUG
1292 static void show_string(struct usb_device *udev, char *id, char *string)
1293 {
1294         if (!string)
1295                 return;
1296         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1297 }
1298
1299 #else
1300 static inline void show_string(struct usb_device *udev, char *id, char *string)
1301 {}
1302 #endif
1303
1304
1305 #ifdef  CONFIG_USB_OTG
1306 #include "otg_whitelist.h"
1307 #endif
1308
1309 /**
1310  * usb_new_device - perform initial device setup (usbcore-internal)
1311  * @udev: newly addressed device (in ADDRESS state)
1312  *
1313  * This is called with devices which have been enumerated, but not yet
1314  * configured.  The device descriptor is available, but not descriptors
1315  * for any device configuration.  The caller must have locked either
1316  * the parent hub (if udev is a normal device) or else the
1317  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1318  * udev has already been installed, but udev is not yet visible through
1319  * sysfs or other filesystem code.
1320  *
1321  * Returns 0 for success (device is configured and listed, with its
1322  * interfaces, in sysfs); else a negative errno value.
1323  *
1324  * This call is synchronous, and may not be used in an interrupt context.
1325  *
1326  * Only the hub driver or root-hub registrar should ever call this.
1327  */
1328 int usb_new_device(struct usb_device *udev)
1329 {
1330         int err;
1331         int c;
1332
1333         err = usb_get_configuration(udev);
1334         if (err < 0) {
1335                 dev_err(&udev->dev, "can't read configurations, error %d\n",
1336                         err);
1337                 goto fail;
1338         }
1339
1340         /* read the standard strings and cache them if present */
1341         udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1342         udev->manufacturer = usb_cache_string(udev,
1343                         udev->descriptor.iManufacturer);
1344         udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1345
1346         /* Tell the world! */
1347         dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1348                         "SerialNumber=%d\n",
1349                         udev->descriptor.iManufacturer,
1350                         udev->descriptor.iProduct,
1351                         udev->descriptor.iSerialNumber);
1352         show_string(udev, "Product", udev->product);
1353         show_string(udev, "Manufacturer", udev->manufacturer);
1354         show_string(udev, "SerialNumber", udev->serial);
1355
1356 #ifdef  CONFIG_USB_OTG
1357         /*
1358          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1359          * to wake us after we've powered off VBUS; and HNP, switching roles
1360          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1361          */
1362         if (!udev->bus->is_b_host
1363                         && udev->config
1364                         && udev->parent == udev->bus->root_hub) {
1365                 struct usb_otg_descriptor       *desc = 0;
1366                 struct usb_bus                  *bus = udev->bus;
1367
1368                 /* descriptor may appear anywhere in config */
1369                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1370                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1371                                         USB_DT_OTG, (void **) &desc) == 0) {
1372                         if (desc->bmAttributes & USB_OTG_HNP) {
1373                                 unsigned                port1 = udev->portnum;
1374                                 struct usb_device       *root = udev->parent;
1375
1376                                 dev_info(&udev->dev,
1377                                         "Dual-Role OTG device on %sHNP port\n",
1378                                         (port1 == bus->otg_port)
1379                                                 ? "" : "non-");
1380
1381                                 /* enable HNP before suspend, it's simpler */
1382                                 if (port1 == bus->otg_port)
1383                                         bus->b_hnp_enable = 1;
1384                                 err = usb_control_msg(udev,
1385                                         usb_sndctrlpipe(udev, 0),
1386                                         USB_REQ_SET_FEATURE, 0,
1387                                         bus->b_hnp_enable
1388                                                 ? USB_DEVICE_B_HNP_ENABLE
1389                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1390                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1391                                 if (err < 0) {
1392                                         /* OTG MESSAGE: report errors here,
1393                                          * customize to match your product.
1394                                          */
1395                                         dev_info(&udev->dev,
1396                                                 "can't set HNP mode; %d\n",
1397                                                 err);
1398                                         bus->b_hnp_enable = 0;
1399                                 }
1400                         }
1401                 }
1402         }
1403
1404         if (!is_targeted(udev)) {
1405
1406                 /* Maybe it can talk to us, though we can't talk to it.
1407                  * (Includes HNP test device.)
1408                  */
1409                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1410                         static int __usb_suspend_device(struct usb_device *,
1411                                                 int port1);
1412                         err = __usb_suspend_device(udev, udev->bus->otg_port);
1413                         if (err < 0)
1414                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1415                 }
1416                 err = -ENODEV;
1417                 goto fail;
1418         }
1419 #endif
1420
1421         /* put device-specific files into sysfs */
1422         err = device_add (&udev->dev);
1423         if (err) {
1424                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1425                 goto fail;
1426         }
1427         usb_create_sysfs_dev_files (udev);
1428
1429         usb_lock_device(udev);
1430
1431         /* choose and set the configuration. that registers the interfaces
1432          * with the driver core, and lets usb device drivers bind to them.
1433          */
1434         c = choose_configuration(udev);
1435         if (c >= 0) {
1436                 err = usb_set_configuration(udev, c);
1437                 if (err) {
1438                         dev_err(&udev->dev, "can't set config #%d, error %d\n",
1439                                         c, err);
1440                         /* This need not be fatal.  The user can try to
1441                          * set other configurations. */
1442                 }
1443         }
1444
1445         /* USB device state == configured ... usable */
1446         usb_notify_add_device(udev);
1447
1448         usb_unlock_device(udev);
1449
1450         return 0;
1451
1452 fail:
1453         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1454         return err;
1455 }
1456
1457
1458 static int hub_port_status(struct usb_hub *hub, int port1,
1459                                u16 *status, u16 *change)
1460 {
1461         int ret;
1462
1463         ret = get_port_status(hub->hdev, port1, &hub->status->port);
1464         if (ret < 0)
1465                 dev_err (hub->intfdev,
1466                         "%s failed (err = %d)\n", __FUNCTION__, ret);
1467         else {
1468                 *status = le16_to_cpu(hub->status->port.wPortStatus);
1469                 *change = le16_to_cpu(hub->status->port.wPortChange);
1470                 ret = 0;
1471         }
1472         return ret;
1473 }
1474
1475 #define PORT_RESET_TRIES        5
1476 #define SET_ADDRESS_TRIES       2
1477 #define GET_DESCRIPTOR_TRIES    2
1478 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1479 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1480
1481 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1482 #define HUB_SHORT_RESET_TIME    10
1483 #define HUB_LONG_RESET_TIME     200
1484 #define HUB_RESET_TIMEOUT       500
1485
1486 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1487                                 struct usb_device *udev, unsigned int delay)
1488 {
1489         int delay_time, ret;
1490         u16 portstatus;
1491         u16 portchange;
1492
1493         for (delay_time = 0;
1494                         delay_time < HUB_RESET_TIMEOUT;
1495                         delay_time += delay) {
1496                 /* wait to give the device a chance to reset */
1497                 msleep(delay);
1498
1499                 /* read and decode port status */
1500                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1501                 if (ret < 0)
1502                         return ret;
1503
1504                 /* Device went away? */
1505                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1506                         return -ENOTCONN;
1507
1508                 /* bomb out completely if something weird happened */
1509                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1510                         return -EINVAL;
1511
1512                 /* if we`ve finished resetting, then break out of the loop */
1513                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1514                     (portstatus & USB_PORT_STAT_ENABLE)) {
1515                         if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1516                                 udev->speed = USB_SPEED_HIGH;
1517                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1518                                 udev->speed = USB_SPEED_LOW;
1519                         else
1520                                 udev->speed = USB_SPEED_FULL;
1521                         return 0;
1522                 }
1523
1524                 /* switch to the long delay after two short delay failures */
1525                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1526                         delay = HUB_LONG_RESET_TIME;
1527
1528                 dev_dbg (hub->intfdev,
1529                         "port %d not reset yet, waiting %dms\n",
1530                         port1, delay);
1531         }
1532
1533         return -EBUSY;
1534 }
1535
1536 static int hub_port_reset(struct usb_hub *hub, int port1,
1537                                 struct usb_device *udev, unsigned int delay)
1538 {
1539         int i, status;
1540
1541         /* Reset the port */
1542         for (i = 0; i < PORT_RESET_TRIES; i++) {
1543                 status = set_port_feature(hub->hdev,
1544                                 port1, USB_PORT_FEAT_RESET);
1545                 if (status)
1546                         dev_err(hub->intfdev,
1547                                         "cannot reset port %d (err = %d)\n",
1548                                         port1, status);
1549                 else {
1550                         status = hub_port_wait_reset(hub, port1, udev, delay);
1551                         if (status && status != -ENOTCONN)
1552                                 dev_dbg(hub->intfdev,
1553                                                 "port_wait_reset: err = %d\n",
1554                                                 status);
1555                 }
1556
1557                 /* return on disconnect or reset */
1558                 switch (status) {
1559                 case 0:
1560                         /* TRSTRCY = 10 ms; plus some extra */
1561                         msleep(10 + 40);
1562                         /* FALL THROUGH */
1563                 case -ENOTCONN:
1564                 case -ENODEV:
1565                         clear_port_feature(hub->hdev,
1566                                 port1, USB_PORT_FEAT_C_RESET);
1567                         /* FIXME need disconnect() for NOTATTACHED device */
1568                         usb_set_device_state(udev, status
1569                                         ? USB_STATE_NOTATTACHED
1570                                         : USB_STATE_DEFAULT);
1571                         return status;
1572                 }
1573
1574                 dev_dbg (hub->intfdev,
1575                         "port %d not enabled, trying reset again...\n",
1576                         port1);
1577                 delay = HUB_LONG_RESET_TIME;
1578         }
1579
1580         dev_err (hub->intfdev,
1581                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1582                 port1);
1583
1584         return status;
1585 }
1586
1587 /*
1588  * Disable a port and mark a logical connnect-change event, so that some
1589  * time later khubd will disconnect() any existing usb_device on the port
1590  * and will re-enumerate if there actually is a device attached.
1591  */
1592 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1593 {
1594         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1595         hub_port_disable(hub, port1, 1);
1596
1597         /* FIXME let caller ask to power down the port:
1598          *  - some devices won't enumerate without a VBUS power cycle
1599          *  - SRP saves power that way
1600          *  - ... new call, TBD ...
1601          * That's easy if this hub can switch power per-port, and
1602          * khubd reactivates the port later (timer, SRP, etc).
1603          * Powerdown must be optional, because of reset/DFU.
1604          */
1605
1606         set_bit(port1, hub->change_bits);
1607         kick_khubd(hub);
1608 }
1609
1610
1611 #ifdef  CONFIG_USB_SUSPEND
1612
1613 /*
1614  * Selective port suspend reduces power; most suspended devices draw
1615  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1616  * All devices below the suspended port are also suspended.
1617  *
1618  * Devices leave suspend state when the host wakes them up.  Some devices
1619  * also support "remote wakeup", where the device can activate the USB
1620  * tree above them to deliver data, such as a keypress or packet.  In
1621  * some cases, this wakes the USB host.
1622  */
1623 static int hub_port_suspend(struct usb_hub *hub, int port1,
1624                 struct usb_device *udev)
1625 {
1626         int     status;
1627
1628         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1629
1630         /* enable remote wakeup when appropriate; this lets the device
1631          * wake up the upstream hub (including maybe the root hub).
1632          *
1633          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1634          * we don't explicitly enable it here.
1635          */
1636         if (device_may_wakeup(&udev->dev)) {
1637                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1638                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1639                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1640                                 NULL, 0,
1641                                 USB_CTRL_SET_TIMEOUT);
1642                 if (status)
1643                         dev_dbg(&udev->dev,
1644                                 "won't remote wakeup, status %d\n",
1645                                 status);
1646         }
1647
1648         /* see 7.1.7.6 */
1649         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1650         if (status) {
1651                 dev_dbg(hub->intfdev,
1652                         "can't suspend port %d, status %d\n",
1653                         port1, status);
1654                 /* paranoia:  "should not happen" */
1655                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1656                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1657                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1658                                 NULL, 0,
1659                                 USB_CTRL_SET_TIMEOUT);
1660         } else {
1661                 /* device has up to 10 msec to fully suspend */
1662                 dev_dbg(&udev->dev, "usb suspend\n");
1663                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1664                 msleep(10);
1665         }
1666         return status;
1667 }
1668
1669 /*
1670  * Devices on USB hub ports have only one "suspend" state, corresponding
1671  * to ACPI D2, "may cause the device to lose some context".
1672  * State transitions include:
1673  *
1674  *   - suspend, resume ... when the VBUS power link stays live
1675  *   - suspend, disconnect ... VBUS lost
1676  *
1677  * Once VBUS drop breaks the circuit, the port it's using has to go through
1678  * normal re-enumeration procedures, starting with enabling VBUS power.
1679  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1680  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1681  * timer, no SRP, no requests through sysfs.
1682  *
1683  * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1684  * the root hub for their bus goes into global suspend ... so we don't
1685  * (falsely) update the device power state to say it suspended.
1686  */
1687 static int __usb_suspend_device (struct usb_device *udev, int port1)
1688 {
1689         int     status = 0;
1690
1691         /* caller owns the udev device lock */
1692         if (port1 < 0)
1693                 return port1;
1694
1695         if (udev->state == USB_STATE_SUSPENDED
1696                         || udev->state == USB_STATE_NOTATTACHED) {
1697                 return 0;
1698         }
1699
1700         /* all interfaces must already be suspended */
1701         if (udev->actconfig) {
1702                 int     i;
1703
1704                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1705                         struct usb_interface    *intf;
1706
1707                         intf = udev->actconfig->interface[i];
1708                         if (is_active(intf)) {
1709                                 dev_dbg(&intf->dev, "nyet suspended\n");
1710                                 return -EBUSY;
1711                         }
1712                 }
1713         }
1714
1715         /* we only change a device's upstream USB link.
1716          * root hubs have no upstream USB link.
1717          */
1718         if (udev->parent)
1719                 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1720                                 udev);
1721
1722         if (status == 0)
1723                 udev->dev.power.power_state = PMSG_SUSPEND;
1724         return status;
1725 }
1726
1727 #endif
1728
1729 /*
1730  * usb_suspend_device - suspend a usb device
1731  * @udev: device that's no longer in active use
1732  * Context: must be able to sleep; device not locked; pm locks held
1733  *
1734  * Suspends a USB device that isn't in active use, conserving power.
1735  * Devices may wake out of a suspend, if anything important happens,
1736  * using the remote wakeup mechanism.  They may also be taken out of
1737  * suspend by the host, using usb_resume_device().  It's also routine
1738  * to disconnect devices while they are suspended.
1739  *
1740  * This only affects the USB hardware for a device; its interfaces
1741  * (and, for hubs, child devices) must already have been suspended.
1742  *
1743  * Suspending OTG devices may trigger HNP, if that's been enabled
1744  * between a pair of dual-role devices.  That will change roles, such
1745  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1746  *
1747  * Returns 0 on success, else negative errno.
1748  */
1749 int usb_suspend_device(struct usb_device *udev)
1750 {
1751 #ifdef  CONFIG_USB_SUSPEND
1752         if (udev->state == USB_STATE_NOTATTACHED)
1753                 return -ENODEV;
1754         return __usb_suspend_device(udev, udev->portnum);
1755 #else
1756         /* NOTE:  udev->state unchanged, it's not lying ... */
1757         udev->dev.power.power_state = PMSG_SUSPEND;
1758         return 0;
1759 #endif
1760 }
1761
1762 /*
1763  * If the USB "suspend" state is in use (rather than "global suspend"),
1764  * many devices will be individually taken out of suspend state using
1765  * special" resume" signaling.  These routines kick in shortly after
1766  * hardware resume signaling is finished, either because of selective
1767  * resume (by host) or remote wakeup (by device) ... now see what changed
1768  * in the tree that's rooted at this device.
1769  */
1770 static int finish_device_resume(struct usb_device *udev)
1771 {
1772         int     status;
1773         u16     devstatus;
1774
1775         /* caller owns the udev device lock */
1776         dev_dbg(&udev->dev, "finish resume\n");
1777
1778         /* usb ch9 identifies four variants of SUSPENDED, based on what
1779          * state the device resumes to.  Linux currently won't see the
1780          * first two on the host side; they'd be inside hub_port_init()
1781          * during many timeouts, but khubd can't suspend until later.
1782          */
1783         usb_set_device_state(udev, udev->actconfig
1784                         ? USB_STATE_CONFIGURED
1785                         : USB_STATE_ADDRESS);
1786         udev->dev.power.power_state = PMSG_ON;
1787
1788         /* 10.5.4.5 says be sure devices in the tree are still there.
1789          * For now let's assume the device didn't go crazy on resume,
1790          * and device drivers will know about any resume quirks.
1791          */
1792         status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1793         if (status >= 0)
1794                 status = (status == 2 ? 0 : -ENODEV);
1795
1796         if (status)
1797                 dev_dbg(&udev->dev,
1798                         "gone after usb resume? status %d\n",
1799                         status);
1800         else if (udev->actconfig) {
1801                 unsigned        i;
1802                 int             (*resume)(struct device *);
1803
1804                 le16_to_cpus(&devstatus);
1805                 if ((devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
1806                                 && udev->parent) {
1807                         status = usb_control_msg(udev,
1808                                         usb_sndctrlpipe(udev, 0),
1809                                         USB_REQ_CLEAR_FEATURE,
1810                                                 USB_RECIP_DEVICE,
1811                                         USB_DEVICE_REMOTE_WAKEUP, 0,
1812                                         NULL, 0,
1813                                         USB_CTRL_SET_TIMEOUT);
1814                         if (status) {
1815                                 dev_dbg(&udev->dev, "disable remote "
1816                                         "wakeup, status %d\n", status);
1817                                 status = 0;
1818                         }
1819                 }
1820
1821                 /* resume interface drivers; if this is a hub, it
1822                  * may have a child resume event to deal with soon
1823                  */
1824                 resume = udev->dev.bus->resume;
1825                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1826                         struct device *dev =
1827                                         &udev->actconfig->interface[i]->dev;
1828
1829                         down(&dev->sem);
1830                         (void) resume(dev);
1831                         up(&dev->sem);
1832                 }
1833                 status = 0;
1834
1835         } else if (udev->devnum <= 0) {
1836                 dev_dbg(&udev->dev, "bogus resume!\n");
1837                 status = -EINVAL;
1838         }
1839         return status;
1840 }
1841
1842 #ifdef  CONFIG_USB_SUSPEND
1843
1844 static int
1845 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1846 {
1847         int     status;
1848
1849         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1850
1851         /* see 7.1.7.7; affects power usage, but not budgeting */
1852         status = clear_port_feature(hub->hdev,
1853                         port1, USB_PORT_FEAT_SUSPEND);
1854         if (status) {
1855                 dev_dbg(hub->intfdev,
1856                         "can't resume port %d, status %d\n",
1857                         port1, status);
1858         } else {
1859                 u16             devstatus;
1860                 u16             portchange;
1861
1862                 /* drive resume for at least 20 msec */
1863                 if (udev)
1864                         dev_dbg(&udev->dev, "RESUME\n");
1865                 msleep(25);
1866
1867 #define LIVE_FLAGS      ( USB_PORT_STAT_POWER \
1868                         | USB_PORT_STAT_ENABLE \
1869                         | USB_PORT_STAT_CONNECTION)
1870
1871                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1872                  * stop resume signaling.  Then finish the resume
1873                  * sequence.
1874                  */
1875                 devstatus = portchange = 0;
1876                 status = hub_port_status(hub, port1,
1877                                 &devstatus, &portchange);
1878                 if (status < 0
1879                                 || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
1880                                 || (devstatus & USB_PORT_STAT_SUSPEND) != 0
1881                                 ) {
1882                         dev_dbg(hub->intfdev,
1883                                 "port %d status %04x.%04x after resume, %d\n",
1884                                 port1, portchange, devstatus, status);
1885                         if (status >= 0)
1886                                 status = -ENODEV;
1887                 } else {
1888                         if (portchange & USB_PORT_STAT_C_SUSPEND)
1889                                 clear_port_feature(hub->hdev, port1,
1890                                                 USB_PORT_FEAT_C_SUSPEND);
1891                         /* TRSMRCY = 10 msec */
1892                         msleep(10);
1893                         if (udev)
1894                                 status = finish_device_resume(udev);
1895                 }
1896         }
1897         if (status < 0)
1898                 hub_port_logical_disconnect(hub, port1);
1899
1900         return status;
1901 }
1902
1903 #endif
1904
1905 /*
1906  * usb_resume_device - re-activate a suspended usb device
1907  * @udev: device to re-activate
1908  * Context: must be able to sleep; device not locked; pm locks held
1909  *
1910  * This will re-activate the suspended device, increasing power usage
1911  * while letting drivers communicate again with its endpoints.
1912  * USB resume explicitly guarantees that the power session between
1913  * the host and the device is the same as it was when the device
1914  * suspended.
1915  *
1916  * Returns 0 on success, else negative errno.
1917  */
1918 int usb_resume_device(struct usb_device *udev)
1919 {
1920         int     status;
1921
1922         if (udev->state == USB_STATE_NOTATTACHED)
1923                 return -ENODEV;
1924
1925         /* selective resume of one downstream hub-to-device port */
1926         if (udev->parent) {
1927 #ifdef  CONFIG_USB_SUSPEND
1928                 if (udev->state == USB_STATE_SUSPENDED) {
1929                         // NOTE swsusp may bork us, device state being wrong...
1930                         // NOTE this fails if parent is also suspended...
1931                         status = hub_port_resume(hdev_to_hub(udev->parent),
1932                                         udev->portnum, udev);
1933                 } else
1934 #endif
1935                         status = 0;
1936         } else
1937                 status = finish_device_resume(udev);
1938         if (status < 0)
1939                 dev_dbg(&udev->dev, "can't resume, status %d\n",
1940                         status);
1941
1942         /* rebind drivers that had no suspend() */
1943         if (status == 0) {
1944                 usb_unlock_device(udev);
1945                 bus_rescan_devices(&usb_bus_type);
1946                 usb_lock_device(udev);
1947         }
1948         return status;
1949 }
1950
1951 static int remote_wakeup(struct usb_device *udev)
1952 {
1953         int     status = 0;
1954
1955 #ifdef  CONFIG_USB_SUSPEND
1956
1957         /* don't repeat RESUME sequence if this device
1958          * was already woken up by some other task
1959          */
1960         usb_lock_device(udev);
1961         if (udev->state == USB_STATE_SUSPENDED) {
1962                 dev_dbg(&udev->dev, "RESUME (wakeup)\n");
1963                 /* TRSMRCY = 10 msec */
1964                 msleep(10);
1965                 status = finish_device_resume(udev);
1966         }
1967         usb_unlock_device(udev);
1968 #endif
1969         return status;
1970 }
1971
1972 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
1973 {
1974         struct usb_hub          *hub = usb_get_intfdata (intf);
1975         struct usb_device       *hdev = hub->hdev;
1976         unsigned                port1;
1977
1978         /* fail if children aren't already suspended */
1979         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1980                 struct usb_device       *udev;
1981
1982                 udev = hdev->children [port1-1];
1983                 if (udev && (udev->dev.power.power_state.event
1984                                         == PM_EVENT_ON
1985 #ifdef  CONFIG_USB_SUSPEND
1986                                 || udev->state != USB_STATE_SUSPENDED
1987 #endif
1988                                 )) {
1989                         dev_dbg(&intf->dev, "port %d nyet suspended\n", port1);
1990                         return -EBUSY;
1991                 }
1992         }
1993
1994         /* "global suspend" of the downstream HC-to-USB interface */
1995         if (!hdev->parent) {
1996                 struct usb_bus  *bus = hdev->bus;
1997                 if (bus) {
1998                         int     status = hcd_bus_suspend (bus);
1999
2000                         if (status != 0) {
2001                                 dev_dbg(&hdev->dev, "'global' suspend %d\n",
2002                                         status);
2003                                 return status;
2004                         }
2005                 } else
2006                         return -EOPNOTSUPP;
2007         }
2008
2009         /* stop khubd and related activity */
2010         hub_quiesce(hub);
2011         return 0;
2012 }
2013
2014 static int hub_resume(struct usb_interface *intf)
2015 {
2016         struct usb_device       *hdev = interface_to_usbdev(intf);
2017         struct usb_hub          *hub = usb_get_intfdata (intf);
2018         int                     status;
2019
2020         /* "global resume" of the downstream HC-to-USB interface */
2021         if (!hdev->parent) {
2022                 struct usb_bus  *bus = hdev->bus;
2023                 if (bus) {
2024                         status = hcd_bus_resume (bus);
2025                         if (status) {
2026                                 dev_dbg(&intf->dev, "'global' resume %d\n",
2027                                         status);
2028                                 return status;
2029                         }
2030                 } else
2031                         return -EOPNOTSUPP;
2032                 if (status == 0) {
2033                         /* TRSMRCY = 10 msec */
2034                         msleep(10);
2035                 }
2036         }
2037
2038         hub_activate(hub);
2039
2040         /* REVISIT:  this recursion probably shouldn't exist.  Remove
2041          * this code sometime, after retesting with different root and
2042          * external hubs.
2043          */
2044 #ifdef  CONFIG_USB_SUSPEND
2045         {
2046         unsigned                port1;
2047
2048         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
2049                 struct usb_device       *udev;
2050                 u16                     portstat, portchange;
2051
2052                 udev = hdev->children [port1-1];
2053                 status = hub_port_status(hub, port1, &portstat, &portchange);
2054                 if (status == 0) {
2055                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2056                                 clear_port_feature(hdev, port1,
2057                                         USB_PORT_FEAT_C_SUSPEND);
2058                                 portchange &= ~USB_PORT_STAT_C_SUSPEND;
2059                         }
2060
2061                         /* let khubd handle disconnects etc */
2062                         if (portchange)
2063                                 continue;
2064                 }
2065
2066                 if (!udev || status < 0)
2067                         continue;
2068                 usb_lock_device(udev);
2069                 if (portstat & USB_PORT_STAT_SUSPEND)
2070                         status = hub_port_resume(hub, port1, udev);
2071                 else {
2072                         status = finish_device_resume(udev);
2073                         if (status < 0) {
2074                                 dev_dbg(&intf->dev, "resume port %d --> %d\n",
2075                                         port1, status);
2076                                 hub_port_logical_disconnect(hub, port1);
2077                         }
2078                 }
2079                 usb_unlock_device(udev);
2080         }
2081         }
2082 #endif
2083         return 0;
2084 }
2085
2086 void usb_suspend_root_hub(struct usb_device *hdev)
2087 {
2088         struct usb_hub *hub = hdev_to_hub(hdev);
2089
2090         /* This also makes any led blinker stop retriggering.  We're called
2091          * from irq, so the blinker might still be scheduled.  Caller promises
2092          * that the root hub status URB will be canceled.
2093          */
2094         __hub_quiesce(hub);
2095         mark_quiesced(to_usb_interface(hub->intfdev));
2096 }
2097
2098 void usb_resume_root_hub(struct usb_device *hdev)
2099 {
2100         struct usb_hub *hub = hdev_to_hub(hdev);
2101
2102         hub->resume_root_hub = 1;
2103         kick_khubd(hub);
2104 }
2105
2106
2107 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2108  *
2109  * Between connect detection and reset signaling there must be a delay
2110  * of 100ms at least for debounce and power-settling.  The corresponding
2111  * timer shall restart whenever the downstream port detects a disconnect.
2112  *
2113  * Apparently there are some bluetooth and irda-dongles and a number of
2114  * low-speed devices for which this debounce period may last over a second.
2115  * Not covered by the spec - but easy to deal with.
2116  *
2117  * This implementation uses a 1500ms total debounce timeout; if the
2118  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
2119  * every 25ms for transient disconnects.  When the port status has been
2120  * unchanged for 100ms it returns the port status.
2121  */
2122
2123 #define HUB_DEBOUNCE_TIMEOUT    1500
2124 #define HUB_DEBOUNCE_STEP         25
2125 #define HUB_DEBOUNCE_STABLE      100
2126
2127 static int hub_port_debounce(struct usb_hub *hub, int port1)
2128 {
2129         int ret;
2130         int total_time, stable_time = 0;
2131         u16 portchange, portstatus;
2132         unsigned connection = 0xffff;
2133
2134         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2135                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2136                 if (ret < 0)
2137                         return ret;
2138
2139                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2140                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2141                         stable_time += HUB_DEBOUNCE_STEP;
2142                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2143                                 break;
2144                 } else {
2145                         stable_time = 0;
2146                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2147                 }
2148
2149                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2150                         clear_port_feature(hub->hdev, port1,
2151                                         USB_PORT_FEAT_C_CONNECTION);
2152                 }
2153
2154                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2155                         break;
2156                 msleep(HUB_DEBOUNCE_STEP);
2157         }
2158
2159         dev_dbg (hub->intfdev,
2160                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2161                 port1, total_time, stable_time, portstatus);
2162
2163         if (stable_time < HUB_DEBOUNCE_STABLE)
2164                 return -ETIMEDOUT;
2165         return portstatus;
2166 }
2167
2168 static void ep0_reinit(struct usb_device *udev)
2169 {
2170         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2171         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2172         udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2173 }
2174
2175 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2176 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2177
2178 static int hub_set_address(struct usb_device *udev)
2179 {
2180         int retval;
2181
2182         if (udev->devnum == 0)
2183                 return -EINVAL;
2184         if (udev->state == USB_STATE_ADDRESS)
2185                 return 0;
2186         if (udev->state != USB_STATE_DEFAULT)
2187                 return -EINVAL;
2188         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2189                 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2190                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2191         if (retval == 0) {
2192                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2193                 ep0_reinit(udev);
2194         }
2195         return retval;
2196 }
2197
2198 /* Reset device, (re)assign address, get device descriptor.
2199  * Device connection must be stable, no more debouncing needed.
2200  * Returns device in USB_STATE_ADDRESS, except on error.
2201  *
2202  * If this is called for an already-existing device (as part of
2203  * usb_reset_device), the caller must own the device lock.  For a
2204  * newly detected device that is not accessible through any global
2205  * pointers, it's not necessary to lock the device.
2206  */
2207 static int
2208 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2209                 int retry_counter)
2210 {
2211         static DEFINE_MUTEX(usb_address0_mutex);
2212
2213         struct usb_device       *hdev = hub->hdev;
2214         int                     i, j, retval;
2215         unsigned                delay = HUB_SHORT_RESET_TIME;
2216         enum usb_device_speed   oldspeed = udev->speed;
2217
2218         /* root hub ports have a slightly longer reset period
2219          * (from USB 2.0 spec, section 7.1.7.5)
2220          */
2221         if (!hdev->parent) {
2222                 delay = HUB_ROOT_RESET_TIME;
2223                 if (port1 == hdev->bus->otg_port)
2224                         hdev->bus->b_hnp_enable = 0;
2225         }
2226
2227         /* Some low speed devices have problems with the quick delay, so */
2228         /*  be a bit pessimistic with those devices. RHbug #23670 */
2229         if (oldspeed == USB_SPEED_LOW)
2230                 delay = HUB_LONG_RESET_TIME;
2231
2232         mutex_lock(&usb_address0_mutex);
2233
2234         /* Reset the device; full speed may morph to high speed */
2235         retval = hub_port_reset(hub, port1, udev, delay);
2236         if (retval < 0)         /* error or disconnect */
2237                 goto fail;
2238                                 /* success, speed is known */
2239         retval = -ENODEV;
2240
2241         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2242                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2243                 goto fail;
2244         }
2245         oldspeed = udev->speed;
2246
2247         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2248          * it's fixed size except for full speed devices.
2249          */
2250         switch (udev->speed) {
2251         case USB_SPEED_HIGH:            /* fixed at 64 */
2252                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2253                 break;
2254         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2255                 /* to determine the ep0 maxpacket size, try to read
2256                  * the device descriptor to get bMaxPacketSize0 and
2257                  * then correct our initial guess.
2258                  */
2259                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2260                 break;
2261         case USB_SPEED_LOW:             /* fixed at 8 */
2262                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2263                 break;
2264         default:
2265                 goto fail;
2266         }
2267
2268         dev_info (&udev->dev,
2269                         "%s %s speed USB device using %s and address %d\n",
2270                         (udev->config) ? "reset" : "new",
2271                         ({ char *speed; switch (udev->speed) {
2272                         case USB_SPEED_LOW:     speed = "low";  break;
2273                         case USB_SPEED_FULL:    speed = "full"; break;
2274                         case USB_SPEED_HIGH:    speed = "high"; break;
2275                         default:                speed = "?";    break;
2276                         }; speed;}),
2277                         udev->bus->controller->driver->name,
2278                         udev->devnum);
2279
2280         /* Set up TT records, if needed  */
2281         if (hdev->tt) {
2282                 udev->tt = hdev->tt;
2283                 udev->ttport = hdev->ttport;
2284         } else if (udev->speed != USB_SPEED_HIGH
2285                         && hdev->speed == USB_SPEED_HIGH) {
2286                 udev->tt = &hub->tt;
2287                 udev->ttport = port1;
2288         }
2289
2290         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2291          * Because device hardware and firmware is sometimes buggy in
2292          * this area, and this is how Linux has done it for ages.
2293          * Change it cautiously.
2294          *
2295          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2296          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2297          * so it may help with some non-standards-compliant devices.
2298          * Otherwise we start with SET_ADDRESS and then try to read the
2299          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2300          * value.
2301          */
2302         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2303                 if (USE_NEW_SCHEME(retry_counter)) {
2304                         struct usb_device_descriptor *buf;
2305                         int r = 0;
2306
2307 #define GET_DESCRIPTOR_BUFSIZE  64
2308                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2309                         if (!buf) {
2310                                 retval = -ENOMEM;
2311                                 continue;
2312                         }
2313
2314                         /* Use a short timeout the first time through,
2315                          * so that recalcitrant full-speed devices with
2316                          * 8- or 16-byte ep0-maxpackets won't slow things
2317                          * down tremendously by NAKing the unexpectedly
2318                          * early status stage.  Also, retry on all errors;
2319                          * some devices are flakey.
2320                          */
2321                         for (j = 0; j < 3; ++j) {
2322                                 buf->bMaxPacketSize0 = 0;
2323                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2324                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2325                                         USB_DT_DEVICE << 8, 0,
2326                                         buf, GET_DESCRIPTOR_BUFSIZE,
2327                                         (i ? USB_CTRL_GET_TIMEOUT : 1000));
2328                                 switch (buf->bMaxPacketSize0) {
2329                                 case 8: case 16: case 32: case 64:
2330                                         if (buf->bDescriptorType ==
2331                                                         USB_DT_DEVICE) {
2332                                                 r = 0;
2333                                                 break;
2334                                         }
2335                                         /* FALL THROUGH */
2336                                 default:
2337                                         if (r == 0)
2338                                                 r = -EPROTO;
2339                                         break;
2340                                 }
2341                                 if (r == 0)
2342                                         break;
2343                         }
2344                         udev->descriptor.bMaxPacketSize0 =
2345                                         buf->bMaxPacketSize0;
2346                         kfree(buf);
2347
2348                         retval = hub_port_reset(hub, port1, udev, delay);
2349                         if (retval < 0)         /* error or disconnect */
2350                                 goto fail;
2351                         if (oldspeed != udev->speed) {
2352                                 dev_dbg(&udev->dev,
2353                                         "device reset changed speed!\n");
2354                                 retval = -ENODEV;
2355                                 goto fail;
2356                         }
2357                         if (r) {
2358                                 dev_err(&udev->dev, "device descriptor "
2359                                                 "read/%s, error %d\n",
2360                                                 "64", r);
2361                                 retval = -EMSGSIZE;
2362                                 continue;
2363                         }
2364 #undef GET_DESCRIPTOR_BUFSIZE
2365                 }
2366
2367                 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2368                         retval = hub_set_address(udev);
2369                         if (retval >= 0)
2370                                 break;
2371                         msleep(200);
2372                 }
2373                 if (retval < 0) {
2374                         dev_err(&udev->dev,
2375                                 "device not accepting address %d, error %d\n",
2376                                 udev->devnum, retval);
2377                         goto fail;
2378                 }
2379
2380                 /* cope with hardware quirkiness:
2381                  *  - let SET_ADDRESS settle, some device hardware wants it
2382                  *  - read ep0 maxpacket even for high and low speed,
2383                  */
2384                 msleep(10);
2385                 if (USE_NEW_SCHEME(retry_counter))
2386                         break;
2387
2388                 retval = usb_get_device_descriptor(udev, 8);
2389                 if (retval < 8) {
2390                         dev_err(&udev->dev, "device descriptor "
2391                                         "read/%s, error %d\n",
2392                                         "8", retval);
2393                         if (retval >= 0)
2394                                 retval = -EMSGSIZE;
2395                 } else {
2396                         retval = 0;
2397                         break;
2398                 }
2399         }
2400         if (retval)
2401                 goto fail;
2402
2403         i = udev->descriptor.bMaxPacketSize0;
2404         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2405                 if (udev->speed != USB_SPEED_FULL ||
2406                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2407                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2408                         retval = -EMSGSIZE;
2409                         goto fail;
2410                 }
2411                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2412                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2413                 ep0_reinit(udev);
2414         }
2415
2416         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2417         if (retval < (signed)sizeof(udev->descriptor)) {
2418                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2419                         "all", retval);
2420                 if (retval >= 0)
2421                         retval = -ENOMSG;
2422                 goto fail;
2423         }
2424
2425         retval = 0;
2426
2427 fail:
2428         if (retval)
2429                 hub_port_disable(hub, port1, 0);
2430         mutex_unlock(&usb_address0_mutex);
2431         return retval;
2432 }
2433
2434 static void
2435 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2436 {
2437         struct usb_qualifier_descriptor *qual;
2438         int                             status;
2439
2440         qual = kmalloc (sizeof *qual, SLAB_KERNEL);
2441         if (qual == NULL)
2442                 return;
2443
2444         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2445                         qual, sizeof *qual);
2446         if (status == sizeof *qual) {
2447                 dev_info(&udev->dev, "not running at top speed; "
2448                         "connect to a high speed hub\n");
2449                 /* hub LEDs are probably harder to miss than syslog */
2450                 if (hub->has_indicators) {
2451                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2452                         schedule_work (&hub->leds);
2453                 }
2454         }
2455         kfree(qual);
2456 }
2457
2458 static unsigned
2459 hub_power_remaining (struct usb_hub *hub)
2460 {
2461         struct usb_device *hdev = hub->hdev;
2462         int remaining;
2463         int port1;
2464
2465         if (!hub->limited_power)
2466                 return 0;
2467
2468         remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
2469         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
2470                 struct usb_device       *udev = hdev->children[port1 - 1];
2471                 int                     delta;
2472
2473                 if (!udev)
2474                         continue;
2475
2476                 /* Unconfigured devices may not use more than 100mA,
2477                  * or 8mA for OTG ports */
2478                 if (udev->actconfig)
2479                         delta = udev->actconfig->desc.bMaxPower * 2;
2480                 else if (port1 != udev->bus->otg_port || hdev->parent)
2481                         delta = 100;
2482                 else
2483                         delta = 8;
2484                 if (delta > hub->mA_per_port)
2485                         dev_warn(&udev->dev, "%dmA is over %umA budget "
2486                                         "for port %d!\n",
2487                                         delta, hub->mA_per_port, port1);
2488                 remaining -= delta;
2489         }
2490         if (remaining < 0) {
2491                 dev_warn(hub->intfdev, "%dmA over power budget!\n",
2492                         - remaining);
2493                 remaining = 0;
2494         }
2495         return remaining;
2496 }
2497
2498 /* Handle physical or logical connection change events.
2499  * This routine is called when:
2500  *      a port connection-change occurs;
2501  *      a port enable-change occurs (often caused by EMI);
2502  *      usb_reset_device() encounters changed descriptors (as from
2503  *              a firmware download)
2504  * caller already locked the hub
2505  */
2506 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2507                                         u16 portstatus, u16 portchange)
2508 {
2509         struct usb_device *hdev = hub->hdev;
2510         struct device *hub_dev = hub->intfdev;
2511         u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2512         int status, i;
2513
2514         dev_dbg (hub_dev,
2515                 "port %d, status %04x, change %04x, %s\n",
2516                 port1, portstatus, portchange, portspeed (portstatus));
2517
2518         if (hub->has_indicators) {
2519                 set_port_led(hub, port1, HUB_LED_AUTO);
2520                 hub->indicator[port1-1] = INDICATOR_AUTO;
2521         }
2522
2523         /* Disconnect any existing devices under this port */
2524         if (hdev->children[port1-1])
2525                 usb_disconnect(&hdev->children[port1-1]);
2526         clear_bit(port1, hub->change_bits);
2527
2528 #ifdef  CONFIG_USB_OTG
2529         /* during HNP, don't repeat the debounce */
2530         if (hdev->bus->is_b_host)
2531                 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2532 #endif
2533
2534         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2535                 status = hub_port_debounce(hub, port1);
2536                 if (status < 0) {
2537                         dev_err (hub_dev,
2538                                 "connect-debounce failed, port %d disabled\n",
2539                                 port1);
2540                         goto done;
2541                 }
2542                 portstatus = status;
2543         }
2544
2545         /* Return now if nothing is connected */
2546         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2547
2548                 /* maybe switch power back on (e.g. root hub was reset) */
2549                 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
2550                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2551                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2552
2553                 if (portstatus & USB_PORT_STAT_ENABLE)
2554                         goto done;
2555                 return;
2556         }
2557
2558 #ifdef  CONFIG_USB_SUSPEND
2559         /* If something is connected, but the port is suspended, wake it up. */
2560         if (portstatus & USB_PORT_STAT_SUSPEND) {
2561                 status = hub_port_resume(hub, port1, NULL);
2562                 if (status < 0) {
2563                         dev_dbg(hub_dev,
2564                                 "can't clear suspend on port %d; %d\n",
2565                                 port1, status);
2566                         goto done;
2567                 }
2568         }
2569 #endif
2570
2571         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2572                 struct usb_device *udev;
2573
2574                 /* reallocate for each attempt, since references
2575                  * to the previous one can escape in various ways
2576                  */
2577                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2578                 if (!udev) {
2579                         dev_err (hub_dev,
2580                                 "couldn't allocate port %d usb_device\n",
2581                                 port1);
2582                         goto done;
2583                 }
2584
2585                 usb_set_device_state(udev, USB_STATE_POWERED);
2586                 udev->speed = USB_SPEED_UNKNOWN;
2587                 udev->bus_mA = hub->mA_per_port;
2588
2589                 /* set the address */
2590                 choose_address(udev);
2591                 if (udev->devnum <= 0) {
2592                         status = -ENOTCONN;     /* Don't retry */
2593                         goto loop;
2594                 }
2595
2596                 /* reset and get descriptor */
2597                 status = hub_port_init(hub, udev, port1, i);
2598                 if (status < 0)
2599                         goto loop;
2600
2601                 /* consecutive bus-powered hubs aren't reliable; they can
2602                  * violate the voltage drop budget.  if the new child has
2603                  * a "powered" LED, users should notice we didn't enable it
2604                  * (without reading syslog), even without per-port LEDs
2605                  * on the parent.
2606                  */
2607                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2608                                 && udev->bus_mA <= 100) {
2609                         u16     devstat;
2610
2611                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2612                                         &devstat);
2613                         if (status < 2) {
2614                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2615                                 goto loop_disable;
2616                         }
2617                         le16_to_cpus(&devstat);
2618                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2619                                 dev_err(&udev->dev,
2620                                         "can't connect bus-powered hub "
2621                                         "to this port\n");
2622                                 if (hub->has_indicators) {
2623                                         hub->indicator[port1-1] =
2624                                                 INDICATOR_AMBER_BLINK;
2625                                         schedule_work (&hub->leds);
2626                                 }
2627                                 status = -ENOTCONN;     /* Don't retry */
2628                                 goto loop_disable;
2629                         }
2630                 }
2631
2632                 /* check for devices running slower than they could */
2633                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2634                                 && udev->speed == USB_SPEED_FULL
2635                                 && highspeed_hubs != 0)
2636                         check_highspeed (hub, udev, port1);
2637
2638                 /* Store the parent's children[] pointer.  At this point
2639                  * udev becomes globally accessible, although presumably
2640                  * no one will look at it until hdev is unlocked.
2641                  */
2642                 status = 0;
2643
2644                 /* We mustn't add new devices if the parent hub has
2645                  * been disconnected; we would race with the
2646                  * recursively_mark_NOTATTACHED() routine.
2647                  */
2648                 spin_lock_irq(&device_state_lock);
2649                 if (hdev->state == USB_STATE_NOTATTACHED)
2650                         status = -ENOTCONN;
2651                 else
2652                         hdev->children[port1-1] = udev;
2653                 spin_unlock_irq(&device_state_lock);
2654
2655                 /* Run it through the hoops (find a driver, etc) */
2656                 if (!status) {
2657                         status = usb_new_device(udev);
2658                         if (status) {
2659                                 spin_lock_irq(&device_state_lock);
2660                                 hdev->children[port1-1] = NULL;
2661                                 spin_unlock_irq(&device_state_lock);
2662                         }
2663                 }
2664
2665                 if (status)
2666                         goto loop_disable;
2667
2668                 status = hub_power_remaining(hub);
2669                 if (status)
2670                         dev_dbg(hub_dev, "%dmA power budget left\n", status);
2671
2672                 return;
2673
2674 loop_disable:
2675                 hub_port_disable(hub, port1, 1);
2676 loop:
2677                 ep0_reinit(udev);
2678                 release_address(udev);
2679                 usb_put_dev(udev);
2680                 if (status == -ENOTCONN)
2681                         break;
2682         }
2683
2684 done:
2685         hub_port_disable(hub, port1, 1);
2686 }
2687
2688 static void hub_events(void)
2689 {
2690         struct list_head *tmp;
2691         struct usb_device *hdev;
2692         struct usb_interface *intf;
2693         struct usb_hub *hub;
2694         struct device *hub_dev;
2695         u16 hubstatus;
2696         u16 hubchange;
2697         u16 portstatus;
2698         u16 portchange;
2699         int i, ret;
2700         int connect_change;
2701
2702         /*
2703          *  We restart the list every time to avoid a deadlock with
2704          * deleting hubs downstream from this one. This should be
2705          * safe since we delete the hub from the event list.
2706          * Not the most efficient, but avoids deadlocks.
2707          */
2708         while (1) {
2709
2710                 /* Grab the first entry at the beginning of the list */
2711                 spin_lock_irq(&hub_event_lock);
2712                 if (list_empty(&hub_event_list)) {
2713                         spin_unlock_irq(&hub_event_lock);
2714                         break;
2715                 }
2716
2717                 tmp = hub_event_list.next;
2718                 list_del_init(tmp);
2719
2720                 hub = list_entry(tmp, struct usb_hub, event_list);
2721                 hdev = hub->hdev;
2722                 intf = to_usb_interface(hub->intfdev);
2723                 hub_dev = &intf->dev;
2724
2725                 i = hub->resume_root_hub;
2726
2727                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x%s\n",
2728                                 hdev->state, hub->descriptor
2729                                         ? hub->descriptor->bNbrPorts
2730                                         : 0,
2731                                 /* NOTE: expects max 15 ports... */
2732                                 (u16) hub->change_bits[0],
2733                                 (u16) hub->event_bits[0],
2734                                 i ? ", resume root" : "");
2735
2736                 usb_get_intf(intf);
2737                 spin_unlock_irq(&hub_event_lock);
2738
2739                 /* Is this is a root hub wanting to reactivate the downstream
2740                  * ports?  If so, be sure the interface resumes even if its
2741                  * stub "device" node was never suspended.
2742                  */
2743                 if (i) {
2744                         dpm_runtime_resume(&hdev->dev);
2745                         dpm_runtime_resume(&intf->dev);
2746                         usb_put_intf(intf);
2747                         continue;
2748                 }
2749
2750                 /* Lock the device, then check to see if we were
2751                  * disconnected while waiting for the lock to succeed. */
2752                 if (locktree(hdev) < 0) {
2753                         usb_put_intf(intf);
2754                         continue;
2755                 }
2756                 if (hub != usb_get_intfdata(intf))
2757                         goto loop;
2758
2759                 /* If the hub has died, clean up after it */
2760                 if (hdev->state == USB_STATE_NOTATTACHED) {
2761                         hub->error = -ENODEV;
2762                         hub_pre_reset(intf);
2763                         goto loop;
2764                 }
2765
2766                 /* If this is an inactive or suspended hub, do nothing */
2767                 if (hub->quiescing)
2768                         goto loop;
2769
2770                 if (hub->error) {
2771                         dev_dbg (hub_dev, "resetting for error %d\n",
2772                                 hub->error);
2773
2774                         ret = usb_reset_composite_device(hdev, intf);
2775                         if (ret) {
2776                                 dev_dbg (hub_dev,
2777                                         "error resetting hub: %d\n", ret);
2778                                 goto loop;
2779                         }
2780
2781                         hub->nerrors = 0;
2782                         hub->error = 0;
2783                 }
2784
2785                 /* deal with port status changes */
2786                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2787                         if (test_bit(i, hub->busy_bits))
2788                                 continue;
2789                         connect_change = test_bit(i, hub->change_bits);
2790                         if (!test_and_clear_bit(i, hub->event_bits) &&
2791                                         !connect_change && !hub->activating)
2792                                 continue;
2793
2794                         ret = hub_port_status(hub, i,
2795                                         &portstatus, &portchange);
2796                         if (ret < 0)
2797                                 continue;
2798
2799                         if (hub->activating && !hdev->children[i-1] &&
2800                                         (portstatus &
2801                                                 USB_PORT_STAT_CONNECTION))
2802                                 connect_change = 1;
2803
2804                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2805                                 clear_port_feature(hdev, i,
2806                                         USB_PORT_FEAT_C_CONNECTION);
2807                                 connect_change = 1;
2808                         }
2809
2810                         if (portchange & USB_PORT_STAT_C_ENABLE) {
2811                                 if (!connect_change)
2812                                         dev_dbg (hub_dev,
2813                                                 "port %d enable change, "
2814                                                 "status %08x\n",
2815                                                 i, portstatus);
2816                                 clear_port_feature(hdev, i,
2817                                         USB_PORT_FEAT_C_ENABLE);
2818
2819                                 /*
2820                                  * EM interference sometimes causes badly
2821                                  * shielded USB devices to be shutdown by
2822                                  * the hub, this hack enables them again.
2823                                  * Works at least with mouse driver.
2824                                  */
2825                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
2826                                     && !connect_change
2827                                     && hdev->children[i-1]) {
2828                                         dev_err (hub_dev,
2829                                             "port %i "
2830                                             "disabled by hub (EMI?), "
2831                                             "re-enabling...\n",
2832                                                 i);
2833                                         connect_change = 1;
2834                                 }
2835                         }
2836
2837                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2838                                 clear_port_feature(hdev, i,
2839                                         USB_PORT_FEAT_C_SUSPEND);
2840                                 if (hdev->children[i-1]) {
2841                                         ret = remote_wakeup(hdev->
2842                                                         children[i-1]);
2843                                         if (ret < 0)
2844                                                 connect_change = 1;
2845                                 } else {
2846                                         ret = -ENODEV;
2847                                         hub_port_disable(hub, i, 1);
2848                                 }
2849                                 dev_dbg (hub_dev,
2850                                         "resume on port %d, status %d\n",
2851                                         i, ret);
2852                         }
2853
2854                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2855                                 dev_err (hub_dev,
2856                                         "over-current change on port %d\n",
2857                                         i);
2858                                 clear_port_feature(hdev, i,
2859                                         USB_PORT_FEAT_C_OVER_CURRENT);
2860                                 hub_power_on(hub);
2861                         }
2862
2863                         if (portchange & USB_PORT_STAT_C_RESET) {
2864                                 dev_dbg (hub_dev,
2865                                         "reset change on port %d\n",
2866                                         i);
2867                                 clear_port_feature(hdev, i,
2868                                         USB_PORT_FEAT_C_RESET);
2869                         }
2870
2871                         if (connect_change)
2872                                 hub_port_connect_change(hub, i,
2873                                                 portstatus, portchange);
2874                 } /* end for i */
2875
2876                 /* deal with hub status changes */
2877                 if (test_and_clear_bit(0, hub->event_bits) == 0)
2878                         ;       /* do nothing */
2879                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2880                         dev_err (hub_dev, "get_hub_status failed\n");
2881                 else {
2882                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2883                                 dev_dbg (hub_dev, "power change\n");
2884                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2885                                 if (hubstatus & HUB_STATUS_LOCAL_POWER)
2886                                         /* FIXME: Is this always true? */
2887                                         hub->limited_power = 0;
2888                                 else
2889                                         hub->limited_power = 1;
2890                         }
2891                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
2892                                 dev_dbg (hub_dev, "overcurrent change\n");
2893                                 msleep(500);    /* Cool down */
2894                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2895                                 hub_power_on(hub);
2896                         }
2897                 }
2898
2899                 hub->activating = 0;
2900
2901                 /* If this is a root hub, tell the HCD it's okay to
2902                  * re-enable port-change interrupts now. */
2903                 if (!hdev->parent)
2904                         usb_enable_root_hub_irq(hdev->bus);
2905
2906 loop:
2907                 usb_unlock_device(hdev);
2908                 usb_put_intf(intf);
2909
2910         } /* end while (1) */
2911 }
2912
2913 static int hub_thread(void *__unused)
2914 {
2915         do {
2916                 hub_events();
2917                 wait_event_interruptible(khubd_wait,
2918                                 !list_empty(&hub_event_list) ||
2919                                 kthread_should_stop());
2920                 try_to_freeze();
2921         } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2922
2923         pr_debug("%s: khubd exiting\n", usbcore_name);
2924         return 0;
2925 }
2926
2927 static struct usb_device_id hub_id_table [] = {
2928     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2929       .bDeviceClass = USB_CLASS_HUB},
2930     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2931       .bInterfaceClass = USB_CLASS_HUB},
2932     { }                                         /* Terminating entry */
2933 };
2934
2935 MODULE_DEVICE_TABLE (usb, hub_id_table);
2936
2937 static struct usb_driver hub_driver = {
2938         .name =         "hub",
2939         .probe =        hub_probe,
2940         .disconnect =   hub_disconnect,
2941         .suspend =      hub_suspend,
2942         .resume =       hub_resume,
2943         .pre_reset =    hub_pre_reset,
2944         .post_reset =   hub_post_reset,
2945         .ioctl =        hub_ioctl,
2946         .id_table =     hub_id_table,
2947 };
2948
2949 int usb_hub_init(void)
2950 {
2951         if (usb_register(&hub_driver) < 0) {
2952                 printk(KERN_ERR "%s: can't register hub driver\n",
2953                         usbcore_name);
2954                 return -1;
2955         }
2956
2957         khubd_task = kthread_run(hub_thread, NULL, "khubd");
2958         if (!IS_ERR(khubd_task))
2959                 return 0;
2960
2961         /* Fall through if kernel_thread failed */
2962         usb_deregister(&hub_driver);
2963         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2964
2965         return -1;
2966 }
2967
2968 void usb_hub_cleanup(void)
2969 {
2970         kthread_stop(khubd_task);
2971
2972         /*
2973          * Hub resources are freed for us by usb_deregister. It calls
2974          * usb_driver_purge on every device which in turn calls that
2975          * devices disconnect function if it is using this driver.
2976          * The hub_disconnect function takes care of releasing the
2977          * individual hub resources. -greg
2978          */
2979         usb_deregister(&hub_driver);
2980 } /* usb_hub_cleanup() */
2981
2982 static int config_descriptors_changed(struct usb_device *udev)
2983 {
2984         unsigned                        index;
2985         unsigned                        len = 0;
2986         struct usb_config_descriptor    *buf;
2987
2988         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2989                 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2990                         len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2991         }
2992         buf = kmalloc (len, SLAB_KERNEL);
2993         if (buf == NULL) {
2994                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2995                 /* assume the worst */
2996                 return 1;
2997         }
2998         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2999                 int length;
3000                 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
3001
3002                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
3003                                 old_length);
3004                 if (length < old_length) {
3005                         dev_dbg(&udev->dev, "config index %d, error %d\n",
3006                                         index, length);
3007                         break;
3008                 }
3009                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
3010                                 != 0) {
3011                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
3012                                 index, buf->bConfigurationValue);
3013                         break;
3014                 }
3015         }
3016         kfree(buf);
3017         return index != udev->descriptor.bNumConfigurations;
3018 }
3019
3020 /**
3021  * usb_reset_device - perform a USB port reset to reinitialize a device
3022  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
3023  *
3024  * WARNING - don't use this routine to reset a composite device
3025  * (one with multiple interfaces owned by separate drivers)!
3026  * Use usb_reset_composite_device() instead.
3027  *
3028  * Do a port reset, reassign the device's address, and establish its
3029  * former operating configuration.  If the reset fails, or the device's
3030  * descriptors change from their values before the reset, or the original
3031  * configuration and altsettings cannot be restored, a flag will be set
3032  * telling khubd to pretend the device has been disconnected and then
3033  * re-connected.  All drivers will be unbound, and the device will be
3034  * re-enumerated and probed all over again.
3035  *
3036  * Returns 0 if the reset succeeded, -ENODEV if the device has been
3037  * flagged for logical disconnection, or some other negative error code
3038  * if the reset wasn't even attempted.
3039  *
3040  * The caller must own the device lock.  For example, it's safe to use
3041  * this from a driver probe() routine after downloading new firmware.
3042  * For calls that might not occur during probe(), drivers should lock
3043  * the device using usb_lock_device_for_reset().
3044  */
3045 int usb_reset_device(struct usb_device *udev)
3046 {
3047         struct usb_device               *parent_hdev = udev->parent;
3048         struct usb_hub                  *parent_hub;
3049         struct usb_device_descriptor    descriptor = udev->descriptor;
3050         int                             i, ret = 0;
3051         int                             port1 = udev->portnum;
3052
3053         if (udev->state == USB_STATE_NOTATTACHED ||
3054                         udev->state == USB_STATE_SUSPENDED) {
3055                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3056                                 udev->state);
3057                 return -EINVAL;
3058         }
3059
3060         if (!parent_hdev) {
3061                 /* this requires hcd-specific logic; see OHCI hc_restart() */
3062                 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
3063                 return -EISDIR;
3064         }
3065         parent_hub = hdev_to_hub(parent_hdev);
3066
3067         set_bit(port1, parent_hub->busy_bits);
3068         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
3069
3070                 /* ep0 maxpacket size may change; let the HCD know about it.
3071                  * Other endpoints will be handled by re-enumeration. */
3072                 ep0_reinit(udev);
3073                 ret = hub_port_init(parent_hub, udev, port1, i);
3074                 if (ret >= 0)
3075                         break;
3076         }
3077         clear_bit(port1, parent_hub->busy_bits);
3078         if (ret < 0)
3079                 goto re_enumerate;
3080
3081         /* Device might have changed firmware (DFU or similar) */
3082         if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
3083                         || config_descriptors_changed (udev)) {
3084                 dev_info(&udev->dev, "device firmware changed\n");
3085                 udev->descriptor = descriptor;  /* for disconnect() calls */
3086                 goto re_enumerate;
3087         }
3088
3089         if (!udev->actconfig)
3090                 goto done;
3091
3092         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3093                         USB_REQ_SET_CONFIGURATION, 0,
3094                         udev->actconfig->desc.bConfigurationValue, 0,
3095                         NULL, 0, USB_CTRL_SET_TIMEOUT);
3096         if (ret < 0) {
3097                 dev_err(&udev->dev,
3098                         "can't restore configuration #%d (error=%d)\n",
3099                         udev->actconfig->desc.bConfigurationValue, ret);
3100                 goto re_enumerate;
3101         }
3102         usb_set_device_state(udev, USB_STATE_CONFIGURED);
3103
3104         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3105                 struct usb_interface *intf = udev->actconfig->interface[i];
3106                 struct usb_interface_descriptor *desc;
3107
3108                 /* set_interface resets host side toggle even
3109                  * for altsetting zero.  the interface may have no driver.
3110                  */
3111                 desc = &intf->cur_altsetting->desc;
3112                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3113                         desc->bAlternateSetting);
3114                 if (ret < 0) {
3115                         dev_err(&udev->dev, "failed to restore interface %d "
3116                                 "altsetting %d (error=%d)\n",
3117                                 desc->bInterfaceNumber,
3118                                 desc->bAlternateSetting,
3119                                 ret);
3120                         goto re_enumerate;
3121                 }
3122         }
3123
3124 done:
3125         return 0;
3126
3127 re_enumerate:
3128         hub_port_logical_disconnect(parent_hub, port1);
3129         return -ENODEV;
3130 }
3131
3132 /**
3133  * usb_reset_composite_device - warn interface drivers and perform a USB port reset
3134  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
3135  * @iface: interface bound to the driver making the request (optional)
3136  *
3137  * Warns all drivers bound to registered interfaces (using their pre_reset
3138  * method), performs the port reset, and then lets the drivers know that
3139  * the reset is over (using their post_reset method).
3140  *
3141  * Return value is the same as for usb_reset_device().
3142  *
3143  * The caller must own the device lock.  For example, it's safe to use
3144  * this from a driver probe() routine after downloading new firmware.
3145  * For calls that might not occur during probe(), drivers should lock
3146  * the device using usb_lock_device_for_reset().
3147  *
3148  * The interface locks are acquired during the pre_reset stage and released
3149  * during the post_reset stage.  However if iface is not NULL and is
3150  * currently being probed, we assume that the caller already owns its
3151  * lock.
3152  */
3153 int usb_reset_composite_device(struct usb_device *udev,
3154                 struct usb_interface *iface)
3155 {
3156         int ret;
3157         struct usb_host_config *config = udev->actconfig;
3158
3159         if (udev->state == USB_STATE_NOTATTACHED ||
3160                         udev->state == USB_STATE_SUSPENDED) {
3161                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3162                                 udev->state);
3163                 return -EINVAL;
3164         }
3165
3166         if (iface && iface->condition != USB_INTERFACE_BINDING)
3167                 iface = NULL;
3168
3169         if (config) {
3170                 int i;
3171                 struct usb_interface *cintf;
3172                 struct usb_driver *drv;
3173
3174                 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
3175                         cintf = config->interface[i];
3176                         if (cintf != iface)
3177                                 down(&cintf->dev.sem);
3178                         if (device_is_registered(&cintf->dev) &&
3179                                         cintf->dev.driver) {
3180                                 drv = to_usb_driver(cintf->dev.driver);
3181                                 if (drv->pre_reset)
3182                                         (drv->pre_reset)(cintf);
3183                         }
3184                 }
3185         }
3186
3187         ret = usb_reset_device(udev);
3188
3189         if (config) {
3190                 int i;
3191                 struct usb_interface *cintf;
3192                 struct usb_driver *drv;
3193
3194                 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
3195                         cintf = config->interface[i];
3196                         if (device_is_registered(&cintf->dev) &&
3197                                         cintf->dev.driver) {
3198                                 drv = to_usb_driver(cintf->dev.driver);
3199                                 if (drv->post_reset)
3200                                         (drv->post_reset)(cintf);
3201                         }
3202                         if (cintf != iface)
3203                                 up(&cintf->dev.sem);
3204                 }
3205         }
3206
3207         return ret;
3208 }