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