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)
 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
1057         /* Make sure no potential wakeup events get lost,
1058          * by forcing the root hub to be resumed.
1059          */
1060         rhdev->dev.power.prev_state.event = PM_EVENT_ON;
1061
1062         spin_lock_irqsave(&device_state_lock, flags);
1063         hub = hdev_to_hub(rhdev);
1064         for (port1 = 1; port1 <= rhdev->maxchild; ++port1) {
1065                 if (rhdev->children[port1 - 1]) {
1066                         recursively_mark_NOTATTACHED(
1067                                         rhdev->children[port1 - 1]);
1068                         set_bit(port1, hub->change_bits);
1069                 }
1070         }
1071         spin_unlock_irqrestore(&device_state_lock, flags);
1072 }
1073 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
1074
1075 #endif  /* CONFIG_PM */
1076
1077 static void choose_address(struct usb_device *udev)
1078 {
1079         int             devnum;
1080         struct usb_bus  *bus = udev->bus;
1081
1082         /* If khubd ever becomes multithreaded, this will need a lock */
1083
1084         /* Try to allocate the next devnum beginning at bus->devnum_next. */
1085         devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1086                         bus->devnum_next);
1087         if (devnum >= 128)
1088                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1089
1090         bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1091
1092         if (devnum < 128) {
1093                 set_bit(devnum, bus->devmap.devicemap);
1094                 udev->devnum = devnum;
1095         }
1096 }
1097
1098 static void release_address(struct usb_device *udev)
1099 {
1100         if (udev->devnum > 0) {
1101                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1102                 udev->devnum = -1;
1103         }
1104 }
1105
1106 /**
1107  * usb_disconnect - disconnect a device (usbcore-internal)
1108  * @pdev: pointer to device being disconnected
1109  * Context: !in_interrupt ()
1110  *
1111  * Something got disconnected. Get rid of it and all of its children.
1112  *
1113  * If *pdev is a normal device then the parent hub must already be locked.
1114  * If *pdev is a root hub then this routine will acquire the
1115  * usb_bus_list_lock on behalf of the caller.
1116  *
1117  * Only hub drivers (including virtual root hub drivers for host
1118  * controllers) should ever call this.
1119  *
1120  * This call is synchronous, and may not be used in an interrupt context.
1121  */
1122 void usb_disconnect(struct usb_device **pdev)
1123 {
1124         struct usb_device       *udev = *pdev;
1125         int                     i;
1126
1127         if (!udev) {
1128                 pr_debug ("%s nodev\n", __FUNCTION__);
1129                 return;
1130         }
1131
1132         /* mark the device as inactive, so any further urb submissions for
1133          * this device (and any of its children) will fail immediately.
1134          * this quiesces everyting except pending urbs.
1135          */
1136         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1137         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1138
1139         usb_lock_device(udev);
1140
1141         /* Free up all the children before we remove this device */
1142         for (i = 0; i < USB_MAXCHILDREN; i++) {
1143                 if (udev->children[i])
1144                         usb_disconnect(&udev->children[i]);
1145         }
1146
1147         /* deallocate hcd/hardware state ... nuking all pending urbs and
1148          * cleaning up all state associated with the current configuration
1149          * so that the hardware is now fully quiesced.
1150          */
1151         dev_dbg (&udev->dev, "unregistering device\n");
1152         usb_disable_device(udev, 0);
1153
1154         usb_unlock_device(udev);
1155
1156         /* Unregister the device.  The device driver is responsible
1157          * for removing the device files from usbfs and sysfs and for
1158          * de-configuring the device.
1159          */
1160         device_del(&udev->dev);
1161
1162         /* Free the device number and delete the parent's children[]
1163          * (or root_hub) pointer.
1164          */
1165         release_address(udev);
1166
1167         /* Avoid races with recursively_mark_NOTATTACHED() */
1168         spin_lock_irq(&device_state_lock);
1169         *pdev = NULL;
1170         spin_unlock_irq(&device_state_lock);
1171
1172         put_device(&udev->dev);
1173 }
1174
1175 #ifdef DEBUG
1176 static void show_string(struct usb_device *udev, char *id, char *string)
1177 {
1178         if (!string)
1179                 return;
1180         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1181 }
1182
1183 #else
1184 static inline void show_string(struct usb_device *udev, char *id, char *string)
1185 {}
1186 #endif
1187
1188
1189 #ifdef  CONFIG_USB_OTG
1190 #include "otg_whitelist.h"
1191 #endif
1192
1193 /**
1194  * usb_new_device - perform initial device setup (usbcore-internal)
1195  * @udev: newly addressed device (in ADDRESS state)
1196  *
1197  * This is called with devices which have been enumerated, but not yet
1198  * configured.  The device descriptor is available, but not descriptors
1199  * for any device configuration.  The caller must have locked either
1200  * the parent hub (if udev is a normal device) or else the
1201  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1202  * udev has already been installed, but udev is not yet visible through
1203  * sysfs or other filesystem code.
1204  *
1205  * Returns 0 for success (device is configured and listed, with its
1206  * interfaces, in sysfs); else a negative errno value.
1207  *
1208  * This call is synchronous, and may not be used in an interrupt context.
1209  *
1210  * Only the hub driver or root-hub registrar should ever call this.
1211  */
1212 int usb_new_device(struct usb_device *udev)
1213 {
1214         int err;
1215
1216         err = usb_get_configuration(udev);
1217         if (err < 0) {
1218                 dev_err(&udev->dev, "can't read configurations, error %d\n",
1219                         err);
1220                 goto fail;
1221         }
1222
1223         /* read the standard strings and cache them if present */
1224         udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1225         udev->manufacturer = usb_cache_string(udev,
1226                         udev->descriptor.iManufacturer);
1227         udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1228
1229         /* Tell the world! */
1230         dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1231                         "SerialNumber=%d\n",
1232                         udev->descriptor.iManufacturer,
1233                         udev->descriptor.iProduct,
1234                         udev->descriptor.iSerialNumber);
1235         show_string(udev, "Product", udev->product);
1236         show_string(udev, "Manufacturer", udev->manufacturer);
1237         show_string(udev, "SerialNumber", udev->serial);
1238
1239 #ifdef  CONFIG_USB_OTG
1240         /*
1241          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1242          * to wake us after we've powered off VBUS; and HNP, switching roles
1243          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1244          */
1245         if (!udev->bus->is_b_host
1246                         && udev->config
1247                         && udev->parent == udev->bus->root_hub) {
1248                 struct usb_otg_descriptor       *desc = 0;
1249                 struct usb_bus                  *bus = udev->bus;
1250
1251                 /* descriptor may appear anywhere in config */
1252                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1253                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1254                                         USB_DT_OTG, (void **) &desc) == 0) {
1255                         if (desc->bmAttributes & USB_OTG_HNP) {
1256                                 unsigned                port1 = udev->portnum;
1257
1258                                 dev_info(&udev->dev,
1259                                         "Dual-Role OTG device on %sHNP port\n",
1260                                         (port1 == bus->otg_port)
1261                                                 ? "" : "non-");
1262
1263                                 /* enable HNP before suspend, it's simpler */
1264                                 if (port1 == bus->otg_port)
1265                                         bus->b_hnp_enable = 1;
1266                                 err = usb_control_msg(udev,
1267                                         usb_sndctrlpipe(udev, 0),
1268                                         USB_REQ_SET_FEATURE, 0,
1269                                         bus->b_hnp_enable
1270                                                 ? USB_DEVICE_B_HNP_ENABLE
1271                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1272                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1273                                 if (err < 0) {
1274                                         /* OTG MESSAGE: report errors here,
1275                                          * customize to match your product.
1276                                          */
1277                                         dev_info(&udev->dev,
1278                                                 "can't set HNP mode; %d\n",
1279                                                 err);
1280                                         bus->b_hnp_enable = 0;
1281                                 }
1282                         }
1283                 }
1284         }
1285
1286         if (!is_targeted(udev)) {
1287
1288                 /* Maybe it can talk to us, though we can't talk to it.
1289                  * (Includes HNP test device.)
1290                  */
1291                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1292                         static int __usb_port_suspend(struct usb_device *,
1293                                                 int port1);
1294                         err = __usb_port_suspend(udev, udev->bus->otg_port);
1295                         if (err < 0)
1296                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1297                 }
1298                 err = -ENODEV;
1299                 goto fail;
1300         }
1301 #endif
1302
1303         /* Register the device.  The device driver is responsible
1304          * for adding the device files to usbfs and sysfs and for
1305          * configuring the device.
1306          */
1307         err = device_add (&udev->dev);
1308         if (err) {
1309                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1310                 goto fail;
1311         }
1312
1313         return 0;
1314
1315 fail:
1316         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1317         return err;
1318 }
1319
1320
1321 static int hub_port_status(struct usb_hub *hub, int port1,
1322                                u16 *status, u16 *change)
1323 {
1324         int ret;
1325
1326         ret = get_port_status(hub->hdev, port1, &hub->status->port);
1327         if (ret < 0)
1328                 dev_err (hub->intfdev,
1329                         "%s failed (err = %d)\n", __FUNCTION__, ret);
1330         else {
1331                 *status = le16_to_cpu(hub->status->port.wPortStatus);
1332                 *change = le16_to_cpu(hub->status->port.wPortChange);
1333                 ret = 0;
1334         }
1335         return ret;
1336 }
1337
1338
1339 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
1340 static unsigned hub_is_wusb(struct usb_hub *hub)
1341 {
1342         struct usb_hcd *hcd;
1343         if (hub->hdev->parent != NULL)  /* not a root hub? */
1344                 return 0;
1345         hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
1346         return hcd->wireless;
1347 }
1348
1349
1350 #define PORT_RESET_TRIES        5
1351 #define SET_ADDRESS_TRIES       2
1352 #define GET_DESCRIPTOR_TRIES    2
1353 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1354 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1355
1356 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1357 #define HUB_SHORT_RESET_TIME    10
1358 #define HUB_LONG_RESET_TIME     200
1359 #define HUB_RESET_TIMEOUT       500
1360
1361 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1362                                 struct usb_device *udev, unsigned int delay)
1363 {
1364         int delay_time, ret;
1365         u16 portstatus;
1366         u16 portchange;
1367
1368         for (delay_time = 0;
1369                         delay_time < HUB_RESET_TIMEOUT;
1370                         delay_time += delay) {
1371                 /* wait to give the device a chance to reset */
1372                 msleep(delay);
1373
1374                 /* read and decode port status */
1375                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1376                 if (ret < 0)
1377                         return ret;
1378
1379                 /* Device went away? */
1380                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1381                         return -ENOTCONN;
1382
1383                 /* bomb out completely if something weird happened */
1384                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1385                         return -EINVAL;
1386
1387                 /* if we`ve finished resetting, then break out of the loop */
1388                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1389                     (portstatus & USB_PORT_STAT_ENABLE)) {
1390                         if (hub_is_wusb(hub))
1391                                 udev->speed = USB_SPEED_VARIABLE;
1392                         else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1393                                 udev->speed = USB_SPEED_HIGH;
1394                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1395                                 udev->speed = USB_SPEED_LOW;
1396                         else
1397                                 udev->speed = USB_SPEED_FULL;
1398                         return 0;
1399                 }
1400
1401                 /* switch to the long delay after two short delay failures */
1402                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1403                         delay = HUB_LONG_RESET_TIME;
1404
1405                 dev_dbg (hub->intfdev,
1406                         "port %d not reset yet, waiting %dms\n",
1407                         port1, delay);
1408         }
1409
1410         return -EBUSY;
1411 }
1412
1413 static int hub_port_reset(struct usb_hub *hub, int port1,
1414                                 struct usb_device *udev, unsigned int delay)
1415 {
1416         int i, status;
1417
1418         /* Reset the port */
1419         for (i = 0; i < PORT_RESET_TRIES; i++) {
1420                 status = set_port_feature(hub->hdev,
1421                                 port1, USB_PORT_FEAT_RESET);
1422                 if (status)
1423                         dev_err(hub->intfdev,
1424                                         "cannot reset port %d (err = %d)\n",
1425                                         port1, status);
1426                 else {
1427                         status = hub_port_wait_reset(hub, port1, udev, delay);
1428                         if (status && status != -ENOTCONN)
1429                                 dev_dbg(hub->intfdev,
1430                                                 "port_wait_reset: err = %d\n",
1431                                                 status);
1432                 }
1433
1434                 /* return on disconnect or reset */
1435                 switch (status) {
1436                 case 0:
1437                         /* TRSTRCY = 10 ms; plus some extra */
1438                         msleep(10 + 40);
1439                         /* FALL THROUGH */
1440                 case -ENOTCONN:
1441                 case -ENODEV:
1442                         clear_port_feature(hub->hdev,
1443                                 port1, USB_PORT_FEAT_C_RESET);
1444                         /* FIXME need disconnect() for NOTATTACHED device */
1445                         usb_set_device_state(udev, status
1446                                         ? USB_STATE_NOTATTACHED
1447                                         : USB_STATE_DEFAULT);
1448                         return status;
1449                 }
1450
1451                 dev_dbg (hub->intfdev,
1452                         "port %d not enabled, trying reset again...\n",
1453                         port1);
1454                 delay = HUB_LONG_RESET_TIME;
1455         }
1456
1457         dev_err (hub->intfdev,
1458                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1459                 port1);
1460
1461         return status;
1462 }
1463
1464 /*
1465  * Disable a port and mark a logical connnect-change event, so that some
1466  * time later khubd will disconnect() any existing usb_device on the port
1467  * and will re-enumerate if there actually is a device attached.
1468  */
1469 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1470 {
1471         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1472         hub_port_disable(hub, port1, 1);
1473
1474         /* FIXME let caller ask to power down the port:
1475          *  - some devices won't enumerate without a VBUS power cycle
1476          *  - SRP saves power that way
1477          *  - ... new call, TBD ...
1478          * That's easy if this hub can switch power per-port, and
1479          * khubd reactivates the port later (timer, SRP, etc).
1480          * Powerdown must be optional, because of reset/DFU.
1481          */
1482
1483         set_bit(port1, hub->change_bits);
1484         kick_khubd(hub);
1485 }
1486
1487 #ifdef  CONFIG_PM
1488
1489 #ifdef  CONFIG_USB_SUSPEND
1490
1491 /*
1492  * Selective port suspend reduces power; most suspended devices draw
1493  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1494  * All devices below the suspended port are also suspended.
1495  *
1496  * Devices leave suspend state when the host wakes them up.  Some devices
1497  * also support "remote wakeup", where the device can activate the USB
1498  * tree above them to deliver data, such as a keypress or packet.  In
1499  * some cases, this wakes the USB host.
1500  */
1501 static int hub_port_suspend(struct usb_hub *hub, int port1,
1502                 struct usb_device *udev)
1503 {
1504         int     status;
1505
1506         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1507
1508         /* enable remote wakeup when appropriate; this lets the device
1509          * wake up the upstream hub (including maybe the root hub).
1510          *
1511          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1512          * we don't explicitly enable it here.
1513          */
1514         if (udev->do_remote_wakeup) {
1515                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1516                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1517                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1518                                 NULL, 0,
1519                                 USB_CTRL_SET_TIMEOUT);
1520                 if (status)
1521                         dev_dbg(&udev->dev,
1522                                 "won't remote wakeup, status %d\n",
1523                                 status);
1524         }
1525
1526         /* see 7.1.7.6 */
1527         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1528         if (status) {
1529                 dev_dbg(hub->intfdev,
1530                         "can't suspend port %d, status %d\n",
1531                         port1, status);
1532                 /* paranoia:  "should not happen" */
1533                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1534                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1535                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1536                                 NULL, 0,
1537                                 USB_CTRL_SET_TIMEOUT);
1538         } else {
1539                 /* device has up to 10 msec to fully suspend */
1540                 dev_dbg(&udev->dev, "usb %ssuspend\n",
1541                                 udev->auto_pm ? "auto-" : "");
1542                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1543                 msleep(10);
1544         }
1545         return status;
1546 }
1547
1548 /*
1549  * Devices on USB hub ports have only one "suspend" state, corresponding
1550  * to ACPI D2, "may cause the device to lose some context".
1551  * State transitions include:
1552  *
1553  *   - suspend, resume ... when the VBUS power link stays live
1554  *   - suspend, disconnect ... VBUS lost
1555  *
1556  * Once VBUS drop breaks the circuit, the port it's using has to go through
1557  * normal re-enumeration procedures, starting with enabling VBUS power.
1558  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1559  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1560  * timer, no SRP, no requests through sysfs.
1561  *
1562  * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1563  * the root hub for their bus goes into global suspend ... so we don't
1564  * (falsely) update the device power state to say it suspended.
1565  */
1566 static int __usb_port_suspend (struct usb_device *udev, int port1)
1567 {
1568         int     status = 0;
1569
1570         /* caller owns the udev device lock */
1571         if (port1 < 0)
1572                 return port1;
1573
1574         /* we change the device's upstream USB link,
1575          * but root hubs have no upstream USB link.
1576          */
1577         if (udev->parent)
1578                 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1579                                 udev);
1580         else {
1581                 dev_dbg(&udev->dev, "usb %ssuspend\n",
1582                                 udev->auto_pm ? "auto-" : "");
1583                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1584         }
1585         return status;
1586 }
1587
1588 /*
1589  * usb_port_suspend - suspend a usb device's upstream port
1590  * @udev: device that's no longer in active use
1591  * Context: must be able to sleep; device not locked; pm locks held
1592  *
1593  * Suspends a USB device that isn't in active use, conserving power.
1594  * Devices may wake out of a suspend, if anything important happens,
1595  * using the remote wakeup mechanism.  They may also be taken out of
1596  * suspend by the host, using usb_port_resume().  It's also routine
1597  * to disconnect devices while they are suspended.
1598  *
1599  * This only affects the USB hardware for a device; its interfaces
1600  * (and, for hubs, child devices) must already have been suspended.
1601  *
1602  * Suspending OTG devices may trigger HNP, if that's been enabled
1603  * between a pair of dual-role devices.  That will change roles, such
1604  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1605  *
1606  * Returns 0 on success, else negative errno.
1607  */
1608 int usb_port_suspend(struct usb_device *udev)
1609 {
1610         return __usb_port_suspend(udev, udev->portnum);
1611 }
1612
1613 /*
1614  * If the USB "suspend" state is in use (rather than "global suspend"),
1615  * many devices will be individually taken out of suspend state using
1616  * special" resume" signaling.  These routines kick in shortly after
1617  * hardware resume signaling is finished, either because of selective
1618  * resume (by host) or remote wakeup (by device) ... now see what changed
1619  * in the tree that's rooted at this device.
1620  */
1621 static int finish_port_resume(struct usb_device *udev)
1622 {
1623         int     status;
1624         u16     devstatus;
1625
1626         /* caller owns the udev device lock */
1627         dev_dbg(&udev->dev, "finish resume\n");
1628
1629         /* usb ch9 identifies four variants of SUSPENDED, based on what
1630          * state the device resumes to.  Linux currently won't see the
1631          * first two on the host side; they'd be inside hub_port_init()
1632          * during many timeouts, but khubd can't suspend until later.
1633          */
1634         usb_set_device_state(udev, udev->actconfig
1635                         ? USB_STATE_CONFIGURED
1636                         : USB_STATE_ADDRESS);
1637
1638         /* 10.5.4.5 says be sure devices in the tree are still there.
1639          * For now let's assume the device didn't go crazy on resume,
1640          * and device drivers will know about any resume quirks.
1641          */
1642         status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1643         if (status >= 0)
1644                 status = (status == 2 ? 0 : -ENODEV);
1645
1646         if (status)
1647                 dev_dbg(&udev->dev,
1648                         "gone after usb resume? status %d\n",
1649                         status);
1650         else if (udev->actconfig) {
1651                 le16_to_cpus(&devstatus);
1652                 if ((devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
1653                                 && udev->parent) {
1654                         status = usb_control_msg(udev,
1655                                         usb_sndctrlpipe(udev, 0),
1656                                         USB_REQ_CLEAR_FEATURE,
1657                                                 USB_RECIP_DEVICE,
1658                                         USB_DEVICE_REMOTE_WAKEUP, 0,
1659                                         NULL, 0,
1660                                         USB_CTRL_SET_TIMEOUT);
1661                         if (status)
1662                                 dev_dbg(&udev->dev, "disable remote "
1663                                         "wakeup, status %d\n", status);
1664                 }
1665                 status = 0;
1666
1667         } else if (udev->devnum <= 0) {
1668                 dev_dbg(&udev->dev, "bogus resume!\n");
1669                 status = -EINVAL;
1670         }
1671         return status;
1672 }
1673
1674 static int
1675 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1676 {
1677         int     status;
1678
1679         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1680
1681         set_bit(port1, hub->busy_bits);
1682
1683         /* see 7.1.7.7; affects power usage, but not budgeting */
1684         status = clear_port_feature(hub->hdev,
1685                         port1, USB_PORT_FEAT_SUSPEND);
1686         if (status) {
1687                 dev_dbg(hub->intfdev,
1688                         "can't resume port %d, status %d\n",
1689                         port1, status);
1690         } else {
1691                 u16             devstatus;
1692                 u16             portchange;
1693
1694                 /* drive resume for at least 20 msec */
1695                 if (udev)
1696                         dev_dbg(&udev->dev, "usb %sresume\n",
1697                                         udev->auto_pm ? "auto-" : "");
1698                 msleep(25);
1699
1700 #define LIVE_FLAGS      ( USB_PORT_STAT_POWER \
1701                         | USB_PORT_STAT_ENABLE \
1702                         | USB_PORT_STAT_CONNECTION)
1703
1704                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1705                  * stop resume signaling.  Then finish the resume
1706                  * sequence.
1707                  */
1708                 devstatus = portchange = 0;
1709                 status = hub_port_status(hub, port1,
1710                                 &devstatus, &portchange);
1711                 if (status < 0
1712                                 || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
1713                                 || (devstatus & USB_PORT_STAT_SUSPEND) != 0
1714                                 ) {
1715                         dev_dbg(hub->intfdev,
1716                                 "port %d status %04x.%04x after resume, %d\n",
1717                                 port1, portchange, devstatus, status);
1718                         if (status >= 0)
1719                                 status = -ENODEV;
1720                 } else {
1721                         if (portchange & USB_PORT_STAT_C_SUSPEND)
1722                                 clear_port_feature(hub->hdev, port1,
1723                                                 USB_PORT_FEAT_C_SUSPEND);
1724                         /* TRSMRCY = 10 msec */
1725                         msleep(10);
1726                         if (udev)
1727                                 status = finish_port_resume(udev);
1728                 }
1729         }
1730         if (status < 0)
1731                 hub_port_logical_disconnect(hub, port1);
1732
1733         clear_bit(port1, hub->busy_bits);
1734         if (!hub->hdev->parent && !hub->busy_bits[0])
1735                 usb_enable_root_hub_irq(hub->hdev->bus);
1736
1737         return status;
1738 }
1739
1740 /*
1741  * usb_port_resume - re-activate a suspended usb device's upstream port
1742  * @udev: device to re-activate
1743  * Context: must be able to sleep; device not locked; pm locks held
1744  *
1745  * This will re-activate the suspended device, increasing power usage
1746  * while letting drivers communicate again with its endpoints.
1747  * USB resume explicitly guarantees that the power session between
1748  * the host and the device is the same as it was when the device
1749  * suspended.
1750  *
1751  * Returns 0 on success, else negative errno.
1752  */
1753 int usb_port_resume(struct usb_device *udev)
1754 {
1755         int     status;
1756
1757         /* we change the device's upstream USB link,
1758          * but root hubs have no upstream USB link.
1759          */
1760         if (udev->parent) {
1761                 // NOTE this fails if parent is also suspended...
1762                 status = hub_port_resume(hdev_to_hub(udev->parent),
1763                                 udev->portnum, udev);
1764         } else {
1765                 dev_dbg(&udev->dev, "usb %sresume\n",
1766                                 udev->auto_pm ? "auto-" : "");
1767                 status = finish_port_resume(udev);
1768         }
1769         if (status < 0)
1770                 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
1771         return status;
1772 }
1773
1774 static int remote_wakeup(struct usb_device *udev)
1775 {
1776         int     status = 0;
1777
1778         /* All this just to avoid sending a port-resume message
1779          * to the parent hub! */
1780
1781         usb_lock_device(udev);
1782         usb_pm_lock(udev);
1783         if (udev->state == USB_STATE_SUSPENDED) {
1784                 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
1785                 /* TRSMRCY = 10 msec */
1786                 msleep(10);
1787                 status = finish_port_resume(udev);
1788                 if (status == 0)
1789                         udev->dev.power.power_state.event = PM_EVENT_ON;
1790         }
1791         usb_pm_unlock(udev);
1792
1793         if (status == 0)
1794                 usb_autoresume_device(udev, 0);
1795         usb_unlock_device(udev);
1796         return status;
1797 }
1798
1799 #else   /* CONFIG_USB_SUSPEND */
1800
1801 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
1802
1803 int usb_port_suspend(struct usb_device *udev)
1804 {
1805         return 0;
1806 }
1807
1808 static inline int
1809 finish_port_resume(struct usb_device *udev)
1810 {
1811         return 0;
1812 }
1813
1814 static inline int
1815 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1816 {
1817         return 0;
1818 }
1819
1820 int usb_port_resume(struct usb_device *udev)
1821 {
1822         return 0;
1823 }
1824
1825 static inline int remote_wakeup(struct usb_device *udev)
1826 {
1827         return 0;
1828 }
1829
1830 #endif
1831
1832 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
1833 {
1834         struct usb_hub          *hub = usb_get_intfdata (intf);
1835         struct usb_device       *hdev = hub->hdev;
1836         unsigned                port1;
1837
1838         /* fail if children aren't already suspended */
1839         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1840                 struct usb_device       *udev;
1841
1842                 udev = hdev->children [port1-1];
1843                 if (udev && msg.event == PM_EVENT_SUSPEND &&
1844 #ifdef  CONFIG_USB_SUSPEND
1845                                 udev->state != USB_STATE_SUSPENDED
1846 #else
1847                                 udev->dev.power.power_state.event
1848                                         == PM_EVENT_ON
1849 #endif
1850                                 ) {
1851                         if (!hdev->auto_pm)
1852                                 dev_dbg(&intf->dev, "port %d nyet suspended\n",
1853                                                 port1);
1854                         return -EBUSY;
1855                 }
1856         }
1857
1858         /* "global suspend" of the downstream HC-to-USB interface */
1859         if (!hdev->parent) {
1860                 struct usb_bus  *bus = hdev->bus;
1861                 if (bus) {
1862                         int     status = hcd_bus_suspend (bus);
1863
1864                         if (status != 0) {
1865                                 dev_dbg(&hdev->dev, "'global' suspend %d\n",
1866                                         status);
1867                                 return status;
1868                         }
1869                 } else
1870                         return -EOPNOTSUPP;
1871         }
1872
1873         /* stop khubd and related activity */
1874         hub_quiesce(hub);
1875         return 0;
1876 }
1877
1878 static int hub_resume(struct usb_interface *intf)
1879 {
1880         struct usb_device       *hdev = interface_to_usbdev(intf);
1881         struct usb_hub          *hub = usb_get_intfdata (intf);
1882         int                     status;
1883
1884         /* "global resume" of the downstream HC-to-USB interface */
1885         if (!hdev->parent) {
1886                 struct usb_bus  *bus = hdev->bus;
1887                 if (bus) {
1888                         status = hcd_bus_resume (bus);
1889                         if (status) {
1890                                 dev_dbg(&intf->dev, "'global' resume %d\n",
1891                                         status);
1892                                 return status;
1893                         }
1894                 } else
1895                         return -EOPNOTSUPP;
1896                 if (status == 0) {
1897                         /* TRSMRCY = 10 msec */
1898                         msleep(10);
1899                 }
1900         }
1901
1902         /* tell khubd to look for changes on this hub */
1903         hub_activate(hub);
1904         return 0;
1905 }
1906
1907 #else   /* CONFIG_PM */
1908
1909 static inline int remote_wakeup(struct usb_device *udev)
1910 {
1911         return 0;
1912 }
1913
1914 #define hub_suspend NULL
1915 #define hub_resume NULL
1916 #endif
1917
1918 void usb_resume_root_hub(struct usb_device *hdev)
1919 {
1920         struct usb_hub *hub = hdev_to_hub(hdev);
1921
1922         hub->resume_root_hub = 1;
1923         kick_khubd(hub);
1924 }
1925
1926
1927 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
1928  *
1929  * Between connect detection and reset signaling there must be a delay
1930  * of 100ms at least for debounce and power-settling.  The corresponding
1931  * timer shall restart whenever the downstream port detects a disconnect.
1932  *
1933  * Apparently there are some bluetooth and irda-dongles and a number of
1934  * low-speed devices for which this debounce period may last over a second.
1935  * Not covered by the spec - but easy to deal with.
1936  *
1937  * This implementation uses a 1500ms total debounce timeout; if the
1938  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
1939  * every 25ms for transient disconnects.  When the port status has been
1940  * unchanged for 100ms it returns the port status.
1941  */
1942
1943 #define HUB_DEBOUNCE_TIMEOUT    1500
1944 #define HUB_DEBOUNCE_STEP         25
1945 #define HUB_DEBOUNCE_STABLE      100
1946
1947 static int hub_port_debounce(struct usb_hub *hub, int port1)
1948 {
1949         int ret;
1950         int total_time, stable_time = 0;
1951         u16 portchange, portstatus;
1952         unsigned connection = 0xffff;
1953
1954         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
1955                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1956                 if (ret < 0)
1957                         return ret;
1958
1959                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
1960                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
1961                         stable_time += HUB_DEBOUNCE_STEP;
1962                         if (stable_time >= HUB_DEBOUNCE_STABLE)
1963                                 break;
1964                 } else {
1965                         stable_time = 0;
1966                         connection = portstatus & USB_PORT_STAT_CONNECTION;
1967                 }
1968
1969                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
1970                         clear_port_feature(hub->hdev, port1,
1971                                         USB_PORT_FEAT_C_CONNECTION);
1972                 }
1973
1974                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
1975                         break;
1976                 msleep(HUB_DEBOUNCE_STEP);
1977         }
1978
1979         dev_dbg (hub->intfdev,
1980                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
1981                 port1, total_time, stable_time, portstatus);
1982
1983         if (stable_time < HUB_DEBOUNCE_STABLE)
1984                 return -ETIMEDOUT;
1985         return portstatus;
1986 }
1987
1988 static void ep0_reinit(struct usb_device *udev)
1989 {
1990         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
1991         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
1992         udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
1993 }
1994
1995 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
1996 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
1997
1998 static int hub_set_address(struct usb_device *udev)
1999 {
2000         int retval;
2001
2002         if (udev->devnum == 0)
2003                 return -EINVAL;
2004         if (udev->state == USB_STATE_ADDRESS)
2005                 return 0;
2006         if (udev->state != USB_STATE_DEFAULT)
2007                 return -EINVAL;
2008         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2009                 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2010                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2011         if (retval == 0) {
2012                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2013                 ep0_reinit(udev);
2014         }
2015         return retval;
2016 }
2017
2018 /* Reset device, (re)assign address, get device descriptor.
2019  * Device connection must be stable, no more debouncing needed.
2020  * Returns device in USB_STATE_ADDRESS, except on error.
2021  *
2022  * If this is called for an already-existing device (as part of
2023  * usb_reset_device), the caller must own the device lock.  For a
2024  * newly detected device that is not accessible through any global
2025  * pointers, it's not necessary to lock the device.
2026  */
2027 static int
2028 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2029                 int retry_counter)
2030 {
2031         static DEFINE_MUTEX(usb_address0_mutex);
2032
2033         struct usb_device       *hdev = hub->hdev;
2034         int                     i, j, retval;
2035         unsigned                delay = HUB_SHORT_RESET_TIME;
2036         enum usb_device_speed   oldspeed = udev->speed;
2037         char                    *speed, *type;
2038
2039         /* root hub ports have a slightly longer reset period
2040          * (from USB 2.0 spec, section 7.1.7.5)
2041          */
2042         if (!hdev->parent) {
2043                 delay = HUB_ROOT_RESET_TIME;
2044                 if (port1 == hdev->bus->otg_port)
2045                         hdev->bus->b_hnp_enable = 0;
2046         }
2047
2048         /* Some low speed devices have problems with the quick delay, so */
2049         /*  be a bit pessimistic with those devices. RHbug #23670 */
2050         if (oldspeed == USB_SPEED_LOW)
2051                 delay = HUB_LONG_RESET_TIME;
2052
2053         mutex_lock(&usb_address0_mutex);
2054
2055         /* Reset the device; full speed may morph to high speed */
2056         retval = hub_port_reset(hub, port1, udev, delay);
2057         if (retval < 0)         /* error or disconnect */
2058                 goto fail;
2059                                 /* success, speed is known */
2060         retval = -ENODEV;
2061
2062         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2063                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2064                 goto fail;
2065         }
2066         oldspeed = udev->speed;
2067
2068         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2069          * it's fixed size except for full speed devices.
2070          * For Wireless USB devices, ep0 max packet is always 512 (tho
2071          * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
2072          */
2073         switch (udev->speed) {
2074         case USB_SPEED_VARIABLE:        /* fixed at 512 */
2075                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(512);
2076                 break;
2077         case USB_SPEED_HIGH:            /* fixed at 64 */
2078                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2079                 break;
2080         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2081                 /* to determine the ep0 maxpacket size, try to read
2082                  * the device descriptor to get bMaxPacketSize0 and
2083                  * then correct our initial guess.
2084                  */
2085                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2086                 break;
2087         case USB_SPEED_LOW:             /* fixed at 8 */
2088                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2089                 break;
2090         default:
2091                 goto fail;
2092         }
2093
2094         type = "";
2095         switch (udev->speed) {
2096         case USB_SPEED_LOW:     speed = "low";  break;
2097         case USB_SPEED_FULL:    speed = "full"; break;
2098         case USB_SPEED_HIGH:    speed = "high"; break;
2099         case USB_SPEED_VARIABLE:
2100                                 speed = "variable";
2101                                 type = "Wireless ";
2102                                 break;
2103         default:                speed = "?";    break;
2104         }
2105         dev_info (&udev->dev,
2106                   "%s %s speed %sUSB device using %s and address %d\n",
2107                   (udev->config) ? "reset" : "new", speed, type,
2108                   udev->bus->controller->driver->name, udev->devnum);
2109
2110         /* Set up TT records, if needed  */
2111         if (hdev->tt) {
2112                 udev->tt = hdev->tt;
2113                 udev->ttport = hdev->ttport;
2114         } else if (udev->speed != USB_SPEED_HIGH
2115                         && hdev->speed == USB_SPEED_HIGH) {
2116                 udev->tt = &hub->tt;
2117                 udev->ttport = port1;
2118         }
2119
2120         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2121          * Because device hardware and firmware is sometimes buggy in
2122          * this area, and this is how Linux has done it for ages.
2123          * Change it cautiously.
2124          *
2125          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2126          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2127          * so it may help with some non-standards-compliant devices.
2128          * Otherwise we start with SET_ADDRESS and then try to read the
2129          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2130          * value.
2131          */
2132         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2133                 if (USE_NEW_SCHEME(retry_counter)) {
2134                         struct usb_device_descriptor *buf;
2135                         int r = 0;
2136
2137 #define GET_DESCRIPTOR_BUFSIZE  64
2138                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2139                         if (!buf) {
2140                                 retval = -ENOMEM;
2141                                 continue;
2142                         }
2143
2144                         /* Use a short timeout the first time through,
2145                          * so that recalcitrant full-speed devices with
2146                          * 8- or 16-byte ep0-maxpackets won't slow things
2147                          * down tremendously by NAKing the unexpectedly
2148                          * early status stage.  Also, retry on all errors;
2149                          * some devices are flakey.
2150                          * 255 is for WUSB devices, we actually need to use 512.
2151                          * WUSB1.0[4.8.1].
2152                          */
2153                         for (j = 0; j < 3; ++j) {
2154                                 buf->bMaxPacketSize0 = 0;
2155                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2156                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2157                                         USB_DT_DEVICE << 8, 0,
2158                                         buf, GET_DESCRIPTOR_BUFSIZE,
2159                                         (i ? USB_CTRL_GET_TIMEOUT : 1000));
2160                                 switch (buf->bMaxPacketSize0) {
2161                                 case 8: case 16: case 32: case 64: case 255:
2162                                         if (buf->bDescriptorType ==
2163                                                         USB_DT_DEVICE) {
2164                                                 r = 0;
2165                                                 break;
2166                                         }
2167                                         /* FALL THROUGH */
2168                                 default:
2169                                         if (r == 0)
2170                                                 r = -EPROTO;
2171                                         break;
2172                                 }
2173                                 if (r == 0)
2174                                         break;
2175                         }
2176                         udev->descriptor.bMaxPacketSize0 =
2177                                         buf->bMaxPacketSize0;
2178                         kfree(buf);
2179
2180                         retval = hub_port_reset(hub, port1, udev, delay);
2181                         if (retval < 0)         /* error or disconnect */
2182                                 goto fail;
2183                         if (oldspeed != udev->speed) {
2184                                 dev_dbg(&udev->dev,
2185                                         "device reset changed speed!\n");
2186                                 retval = -ENODEV;
2187                                 goto fail;
2188                         }
2189                         if (r) {
2190                                 dev_err(&udev->dev, "device descriptor "
2191                                                 "read/%s, error %d\n",
2192                                                 "64", r);
2193                                 retval = -EMSGSIZE;
2194                                 continue;
2195                         }
2196 #undef GET_DESCRIPTOR_BUFSIZE
2197                 }
2198
2199                 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2200                         retval = hub_set_address(udev);
2201                         if (retval >= 0)
2202                                 break;
2203                         msleep(200);
2204                 }
2205                 if (retval < 0) {
2206                         dev_err(&udev->dev,
2207                                 "device not accepting address %d, error %d\n",
2208                                 udev->devnum, retval);
2209                         goto fail;
2210                 }
2211
2212                 /* cope with hardware quirkiness:
2213                  *  - let SET_ADDRESS settle, some device hardware wants it
2214                  *  - read ep0 maxpacket even for high and low speed,
2215                  */
2216                 msleep(10);
2217                 if (USE_NEW_SCHEME(retry_counter))
2218                         break;
2219
2220                 retval = usb_get_device_descriptor(udev, 8);
2221                 if (retval < 8) {
2222                         dev_err(&udev->dev, "device descriptor "
2223                                         "read/%s, error %d\n",
2224                                         "8", retval);
2225                         if (retval >= 0)
2226                                 retval = -EMSGSIZE;
2227                 } else {
2228                         retval = 0;
2229                         break;
2230                 }
2231         }
2232         if (retval)
2233                 goto fail;
2234
2235         i = udev->descriptor.bMaxPacketSize0 == 0xff?
2236             512 : udev->descriptor.bMaxPacketSize0;
2237         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2238                 if (udev->speed != USB_SPEED_FULL ||
2239                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2240                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2241                         retval = -EMSGSIZE;
2242                         goto fail;
2243                 }
2244                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2245                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2246                 ep0_reinit(udev);
2247         }
2248
2249         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2250         if (retval < (signed)sizeof(udev->descriptor)) {
2251                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2252                         "all", retval);
2253                 if (retval >= 0)
2254                         retval = -ENOMSG;
2255                 goto fail;
2256         }
2257
2258         retval = 0;
2259
2260 fail:
2261         if (retval)
2262                 hub_port_disable(hub, port1, 0);
2263         mutex_unlock(&usb_address0_mutex);
2264         return retval;
2265 }
2266
2267 static void
2268 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2269 {
2270         struct usb_qualifier_descriptor *qual;
2271         int                             status;
2272
2273         qual = kmalloc (sizeof *qual, SLAB_KERNEL);
2274         if (qual == NULL)
2275                 return;
2276
2277         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2278                         qual, sizeof *qual);
2279         if (status == sizeof *qual) {
2280                 dev_info(&udev->dev, "not running at top speed; "
2281                         "connect to a high speed hub\n");
2282                 /* hub LEDs are probably harder to miss than syslog */
2283                 if (hub->has_indicators) {
2284                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2285                         schedule_work (&hub->leds);
2286                 }
2287         }
2288         kfree(qual);
2289 }
2290
2291 static unsigned
2292 hub_power_remaining (struct usb_hub *hub)
2293 {
2294         struct usb_device *hdev = hub->hdev;
2295         int remaining;
2296         int port1;
2297
2298         if (!hub->limited_power)
2299                 return 0;
2300
2301         remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
2302         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
2303                 struct usb_device       *udev = hdev->children[port1 - 1];
2304                 int                     delta;
2305
2306                 if (!udev)
2307                         continue;
2308
2309                 /* Unconfigured devices may not use more than 100mA,
2310                  * or 8mA for OTG ports */
2311                 if (udev->actconfig)
2312                         delta = udev->actconfig->desc.bMaxPower * 2;
2313                 else if (port1 != udev->bus->otg_port || hdev->parent)
2314                         delta = 100;
2315                 else
2316                         delta = 8;
2317                 if (delta > hub->mA_per_port)
2318                         dev_warn(&udev->dev, "%dmA is over %umA budget "
2319                                         "for port %d!\n",
2320                                         delta, hub->mA_per_port, port1);
2321                 remaining -= delta;
2322         }
2323         if (remaining < 0) {
2324                 dev_warn(hub->intfdev, "%dmA over power budget!\n",
2325                         - remaining);
2326                 remaining = 0;
2327         }
2328         return remaining;
2329 }
2330
2331 /* Handle physical or logical connection change events.
2332  * This routine is called when:
2333  *      a port connection-change occurs;
2334  *      a port enable-change occurs (often caused by EMI);
2335  *      usb_reset_device() encounters changed descriptors (as from
2336  *              a firmware download)
2337  * caller already locked the hub
2338  */
2339 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2340                                         u16 portstatus, u16 portchange)
2341 {
2342         struct usb_device *hdev = hub->hdev;
2343         struct device *hub_dev = hub->intfdev;
2344         u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2345         int status, i;
2346
2347         dev_dbg (hub_dev,
2348                 "port %d, status %04x, change %04x, %s\n",
2349                 port1, portstatus, portchange, portspeed (portstatus));
2350
2351         if (hub->has_indicators) {
2352                 set_port_led(hub, port1, HUB_LED_AUTO);
2353                 hub->indicator[port1-1] = INDICATOR_AUTO;
2354         }
2355
2356         /* Disconnect any existing devices under this port */
2357         if (hdev->children[port1-1])
2358                 usb_disconnect(&hdev->children[port1-1]);
2359         clear_bit(port1, hub->change_bits);
2360
2361 #ifdef  CONFIG_USB_OTG
2362         /* during HNP, don't repeat the debounce */
2363         if (hdev->bus->is_b_host)
2364                 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2365 #endif
2366
2367         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2368                 status = hub_port_debounce(hub, port1);
2369                 if (status < 0) {
2370                         dev_err (hub_dev,
2371                                 "connect-debounce failed, port %d disabled\n",
2372                                 port1);
2373                         goto done;
2374                 }
2375                 portstatus = status;
2376         }
2377
2378         /* Return now if nothing is connected */
2379         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2380
2381                 /* maybe switch power back on (e.g. root hub was reset) */
2382                 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
2383                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2384                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2385
2386                 if (portstatus & USB_PORT_STAT_ENABLE)
2387                         goto done;
2388                 return;
2389         }
2390
2391 #ifdef  CONFIG_USB_SUSPEND
2392         /* If something is connected, but the port is suspended, wake it up. */
2393         if (portstatus & USB_PORT_STAT_SUSPEND) {
2394                 status = hub_port_resume(hub, port1, NULL);
2395                 if (status < 0) {
2396                         dev_dbg(hub_dev,
2397                                 "can't clear suspend on port %d; %d\n",
2398                                 port1, status);
2399                         goto done;
2400                 }
2401         }
2402 #endif
2403
2404         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2405                 struct usb_device *udev;
2406
2407                 /* reallocate for each attempt, since references
2408                  * to the previous one can escape in various ways
2409                  */
2410                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2411                 if (!udev) {
2412                         dev_err (hub_dev,
2413                                 "couldn't allocate port %d usb_device\n",
2414                                 port1);
2415                         goto done;
2416                 }
2417
2418                 usb_set_device_state(udev, USB_STATE_POWERED);
2419                 udev->speed = USB_SPEED_UNKNOWN;
2420                 udev->bus_mA = hub->mA_per_port;
2421                 udev->level = hdev->level + 1;
2422
2423                 /* set the address */
2424                 choose_address(udev);
2425                 if (udev->devnum <= 0) {
2426                         status = -ENOTCONN;     /* Don't retry */
2427                         goto loop;
2428                 }
2429
2430                 /* reset and get descriptor */
2431                 status = hub_port_init(hub, udev, port1, i);
2432                 if (status < 0)
2433                         goto loop;
2434
2435                 /* consecutive bus-powered hubs aren't reliable; they can
2436                  * violate the voltage drop budget.  if the new child has
2437                  * a "powered" LED, users should notice we didn't enable it
2438                  * (without reading syslog), even without per-port LEDs
2439                  * on the parent.
2440                  */
2441                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2442                                 && udev->bus_mA <= 100) {
2443                         u16     devstat;
2444
2445                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2446                                         &devstat);
2447                         if (status < 2) {
2448                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2449                                 goto loop_disable;
2450                         }
2451                         le16_to_cpus(&devstat);
2452                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2453                                 dev_err(&udev->dev,
2454                                         "can't connect bus-powered hub "
2455                                         "to this port\n");
2456                                 if (hub->has_indicators) {
2457                                         hub->indicator[port1-1] =
2458                                                 INDICATOR_AMBER_BLINK;
2459                                         schedule_work (&hub->leds);
2460                                 }
2461                                 status = -ENOTCONN;     /* Don't retry */
2462                                 goto loop_disable;
2463                         }
2464                 }
2465
2466                 /* check for devices running slower than they could */
2467                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2468                                 && udev->speed == USB_SPEED_FULL
2469                                 && highspeed_hubs != 0)
2470                         check_highspeed (hub, udev, port1);
2471
2472                 /* Store the parent's children[] pointer.  At this point
2473                  * udev becomes globally accessible, although presumably
2474                  * no one will look at it until hdev is unlocked.
2475                  */
2476                 status = 0;
2477
2478                 /* We mustn't add new devices if the parent hub has
2479                  * been disconnected; we would race with the
2480                  * recursively_mark_NOTATTACHED() routine.
2481                  */
2482                 spin_lock_irq(&device_state_lock);
2483                 if (hdev->state == USB_STATE_NOTATTACHED)
2484                         status = -ENOTCONN;
2485                 else
2486                         hdev->children[port1-1] = udev;
2487                 spin_unlock_irq(&device_state_lock);
2488
2489                 /* Run it through the hoops (find a driver, etc) */
2490                 if (!status) {
2491                         status = usb_new_device(udev);
2492                         if (status) {
2493                                 spin_lock_irq(&device_state_lock);
2494                                 hdev->children[port1-1] = NULL;
2495                                 spin_unlock_irq(&device_state_lock);
2496                         }
2497                 }
2498
2499                 if (status)
2500                         goto loop_disable;
2501
2502                 status = hub_power_remaining(hub);
2503                 if (status)
2504                         dev_dbg(hub_dev, "%dmA power budget left\n", status);
2505
2506                 return;
2507
2508 loop_disable:
2509                 hub_port_disable(hub, port1, 1);
2510 loop:
2511                 ep0_reinit(udev);
2512                 release_address(udev);
2513                 usb_put_dev(udev);
2514                 if (status == -ENOTCONN)
2515                         break;
2516         }
2517
2518 done:
2519         hub_port_disable(hub, port1, 1);
2520 }
2521
2522 static void hub_events(void)
2523 {
2524         struct list_head *tmp;
2525         struct usb_device *hdev;
2526         struct usb_interface *intf;
2527         struct usb_hub *hub;
2528         struct device *hub_dev;
2529         u16 hubstatus;
2530         u16 hubchange;
2531         u16 portstatus;
2532         u16 portchange;
2533         int i, ret;
2534         int connect_change;
2535
2536         /*
2537          *  We restart the list every time to avoid a deadlock with
2538          * deleting hubs downstream from this one. This should be
2539          * safe since we delete the hub from the event list.
2540          * Not the most efficient, but avoids deadlocks.
2541          */
2542         while (1) {
2543
2544                 /* Grab the first entry at the beginning of the list */
2545                 spin_lock_irq(&hub_event_lock);
2546                 if (list_empty(&hub_event_list)) {
2547                         spin_unlock_irq(&hub_event_lock);
2548                         break;
2549                 }
2550
2551                 tmp = hub_event_list.next;
2552                 list_del_init(tmp);
2553
2554                 hub = list_entry(tmp, struct usb_hub, event_list);
2555                 hdev = hub->hdev;
2556                 intf = to_usb_interface(hub->intfdev);
2557                 hub_dev = &intf->dev;
2558
2559                 i = hub->resume_root_hub;
2560
2561                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x%s\n",
2562                                 hdev->state, hub->descriptor
2563                                         ? hub->descriptor->bNbrPorts
2564                                         : 0,
2565                                 /* NOTE: expects max 15 ports... */
2566                                 (u16) hub->change_bits[0],
2567                                 (u16) hub->event_bits[0],
2568                                 i ? ", resume root" : "");
2569
2570                 usb_get_intf(intf);
2571                 spin_unlock_irq(&hub_event_lock);
2572
2573                 /* Lock the device, then check to see if we were
2574                  * disconnected while waiting for the lock to succeed. */
2575                 if (locktree(hdev) < 0) {
2576                         usb_put_intf(intf);
2577                         continue;
2578                 }
2579                 if (hub != usb_get_intfdata(intf))
2580                         goto loop;
2581
2582                 /* If the hub has died, clean up after it */
2583                 if (hdev->state == USB_STATE_NOTATTACHED) {
2584                         hub->error = -ENODEV;
2585                         hub_pre_reset(intf);
2586                         goto loop;
2587                 }
2588
2589                 /* Is this is a root hub wanting to reactivate the downstream
2590                  * ports?  If so, be sure the interface resumes even if its
2591                  * stub "device" node was never suspended.
2592                  */
2593                 if (i)
2594                         usb_autoresume_device(hdev, 0);
2595
2596                 /* If this is an inactive or suspended hub, do nothing */
2597                 if (hub->quiescing)
2598                         goto loop;
2599
2600                 if (hub->error) {
2601                         dev_dbg (hub_dev, "resetting for error %d\n",
2602                                 hub->error);
2603
2604                         ret = usb_reset_composite_device(hdev, intf);
2605                         if (ret) {
2606                                 dev_dbg (hub_dev,
2607                                         "error resetting hub: %d\n", ret);
2608                                 goto loop;
2609                         }
2610
2611                         hub->nerrors = 0;
2612                         hub->error = 0;
2613                 }
2614
2615                 /* deal with port status changes */
2616                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2617                         if (test_bit(i, hub->busy_bits))
2618                                 continue;
2619                         connect_change = test_bit(i, hub->change_bits);
2620                         if (!test_and_clear_bit(i, hub->event_bits) &&
2621                                         !connect_change && !hub->activating)
2622                                 continue;
2623
2624                         ret = hub_port_status(hub, i,
2625                                         &portstatus, &portchange);
2626                         if (ret < 0)
2627                                 continue;
2628
2629                         if (hub->activating && !hdev->children[i-1] &&
2630                                         (portstatus &
2631                                                 USB_PORT_STAT_CONNECTION))
2632                                 connect_change = 1;
2633
2634                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2635                                 clear_port_feature(hdev, i,
2636                                         USB_PORT_FEAT_C_CONNECTION);
2637                                 connect_change = 1;
2638                         }
2639
2640                         if (portchange & USB_PORT_STAT_C_ENABLE) {
2641                                 if (!connect_change)
2642                                         dev_dbg (hub_dev,
2643                                                 "port %d enable change, "
2644                                                 "status %08x\n",
2645                                                 i, portstatus);
2646                                 clear_port_feature(hdev, i,
2647                                         USB_PORT_FEAT_C_ENABLE);
2648
2649                                 /*
2650                                  * EM interference sometimes causes badly
2651                                  * shielded USB devices to be shutdown by
2652                                  * the hub, this hack enables them again.
2653                                  * Works at least with mouse driver.
2654                                  */
2655                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
2656                                     && !connect_change
2657                                     && hdev->children[i-1]) {
2658                                         dev_err (hub_dev,
2659                                             "port %i "
2660                                             "disabled by hub (EMI?), "
2661                                             "re-enabling...\n",
2662                                                 i);
2663                                         connect_change = 1;
2664                                 }
2665                         }
2666
2667                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2668                                 clear_port_feature(hdev, i,
2669                                         USB_PORT_FEAT_C_SUSPEND);
2670                                 if (hdev->children[i-1]) {
2671                                         ret = remote_wakeup(hdev->
2672                                                         children[i-1]);
2673                                         if (ret < 0)
2674                                                 connect_change = 1;
2675                                 } else {
2676                                         ret = -ENODEV;
2677                                         hub_port_disable(hub, i, 1);
2678                                 }
2679                                 dev_dbg (hub_dev,
2680                                         "resume on port %d, status %d\n",
2681                                         i, ret);
2682                         }
2683
2684                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2685                                 dev_err (hub_dev,
2686                                         "over-current change on port %d\n",
2687                                         i);
2688                                 clear_port_feature(hdev, i,
2689                                         USB_PORT_FEAT_C_OVER_CURRENT);
2690                                 hub_power_on(hub);
2691                         }
2692
2693                         if (portchange & USB_PORT_STAT_C_RESET) {
2694                                 dev_dbg (hub_dev,
2695                                         "reset change on port %d\n",
2696                                         i);
2697                                 clear_port_feature(hdev, i,
2698                                         USB_PORT_FEAT_C_RESET);
2699                         }
2700
2701                         if (connect_change)
2702                                 hub_port_connect_change(hub, i,
2703                                                 portstatus, portchange);
2704                 } /* end for i */
2705
2706                 /* deal with hub status changes */
2707                 if (test_and_clear_bit(0, hub->event_bits) == 0)
2708                         ;       /* do nothing */
2709                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2710                         dev_err (hub_dev, "get_hub_status failed\n");
2711                 else {
2712                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2713                                 dev_dbg (hub_dev, "power change\n");
2714                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2715                                 if (hubstatus & HUB_STATUS_LOCAL_POWER)
2716                                         /* FIXME: Is this always true? */
2717                                         hub->limited_power = 0;
2718                                 else
2719                                         hub->limited_power = 1;
2720                         }
2721                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
2722                                 dev_dbg (hub_dev, "overcurrent change\n");
2723                                 msleep(500);    /* Cool down */
2724                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2725                                 hub_power_on(hub);
2726                         }
2727                 }
2728
2729                 hub->activating = 0;
2730
2731                 /* If this is a root hub, tell the HCD it's okay to
2732                  * re-enable port-change interrupts now. */
2733                 if (!hdev->parent && !hub->busy_bits[0])
2734                         usb_enable_root_hub_irq(hdev->bus);
2735
2736 loop:
2737                 usb_unlock_device(hdev);
2738                 usb_put_intf(intf);
2739
2740         } /* end while (1) */
2741 }
2742
2743 static int hub_thread(void *__unused)
2744 {
2745         do {
2746                 hub_events();
2747                 wait_event_interruptible(khubd_wait,
2748                                 !list_empty(&hub_event_list) ||
2749                                 kthread_should_stop());
2750                 try_to_freeze();
2751         } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2752
2753         pr_debug("%s: khubd exiting\n", usbcore_name);
2754         return 0;
2755 }
2756
2757 static struct usb_device_id hub_id_table [] = {
2758     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2759       .bDeviceClass = USB_CLASS_HUB},
2760     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2761       .bInterfaceClass = USB_CLASS_HUB},
2762     { }                                         /* Terminating entry */
2763 };
2764
2765 MODULE_DEVICE_TABLE (usb, hub_id_table);
2766
2767 static struct usb_driver hub_driver = {
2768         .name =         "hub",
2769         .probe =        hub_probe,
2770         .disconnect =   hub_disconnect,
2771         .suspend =      hub_suspend,
2772         .resume =       hub_resume,
2773         .pre_reset =    hub_pre_reset,
2774         .post_reset =   hub_post_reset,
2775         .ioctl =        hub_ioctl,
2776         .id_table =     hub_id_table,
2777 };
2778
2779 int usb_hub_init(void)
2780 {
2781         if (usb_register(&hub_driver) < 0) {
2782                 printk(KERN_ERR "%s: can't register hub driver\n",
2783                         usbcore_name);
2784                 return -1;
2785         }
2786
2787         khubd_task = kthread_run(hub_thread, NULL, "khubd");
2788         if (!IS_ERR(khubd_task))
2789                 return 0;
2790
2791         /* Fall through if kernel_thread failed */
2792         usb_deregister(&hub_driver);
2793         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2794
2795         return -1;
2796 }
2797
2798 void usb_hub_cleanup(void)
2799 {
2800         kthread_stop(khubd_task);
2801
2802         /*
2803          * Hub resources are freed for us by usb_deregister. It calls
2804          * usb_driver_purge on every device which in turn calls that
2805          * devices disconnect function if it is using this driver.
2806          * The hub_disconnect function takes care of releasing the
2807          * individual hub resources. -greg
2808          */
2809         usb_deregister(&hub_driver);
2810 } /* usb_hub_cleanup() */
2811
2812 static int config_descriptors_changed(struct usb_device *udev)
2813 {
2814         unsigned                        index;
2815         unsigned                        len = 0;
2816         struct usb_config_descriptor    *buf;
2817
2818         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2819                 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2820                         len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2821         }
2822         buf = kmalloc (len, SLAB_KERNEL);
2823         if (buf == NULL) {
2824                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2825                 /* assume the worst */
2826                 return 1;
2827         }
2828         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2829                 int length;
2830                 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2831
2832                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2833                                 old_length);
2834                 if (length < old_length) {
2835                         dev_dbg(&udev->dev, "config index %d, error %d\n",
2836                                         index, length);
2837                         break;
2838                 }
2839                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2840                                 != 0) {
2841                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2842                                 index, buf->bConfigurationValue);
2843                         break;
2844                 }
2845         }
2846         kfree(buf);
2847         return index != udev->descriptor.bNumConfigurations;
2848 }
2849
2850 /**
2851  * usb_reset_device - perform a USB port reset to reinitialize a device
2852  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2853  *
2854  * WARNING - don't use this routine to reset a composite device
2855  * (one with multiple interfaces owned by separate drivers)!
2856  * Use usb_reset_composite_device() instead.
2857  *
2858  * Do a port reset, reassign the device's address, and establish its
2859  * former operating configuration.  If the reset fails, or the device's
2860  * descriptors change from their values before the reset, or the original
2861  * configuration and altsettings cannot be restored, a flag will be set
2862  * telling khubd to pretend the device has been disconnected and then
2863  * re-connected.  All drivers will be unbound, and the device will be
2864  * re-enumerated and probed all over again.
2865  *
2866  * Returns 0 if the reset succeeded, -ENODEV if the device has been
2867  * flagged for logical disconnection, or some other negative error code
2868  * if the reset wasn't even attempted.
2869  *
2870  * The caller must own the device lock.  For example, it's safe to use
2871  * this from a driver probe() routine after downloading new firmware.
2872  * For calls that might not occur during probe(), drivers should lock
2873  * the device using usb_lock_device_for_reset().
2874  */
2875 int usb_reset_device(struct usb_device *udev)
2876 {
2877         struct usb_device               *parent_hdev = udev->parent;
2878         struct usb_hub                  *parent_hub;
2879         struct usb_device_descriptor    descriptor = udev->descriptor;
2880         int                             i, ret = 0;
2881         int                             port1 = udev->portnum;
2882
2883         if (udev->state == USB_STATE_NOTATTACHED ||
2884                         udev->state == USB_STATE_SUSPENDED) {
2885                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2886                                 udev->state);
2887                 return -EINVAL;
2888         }
2889
2890         if (!parent_hdev) {
2891                 /* this requires hcd-specific logic; see OHCI hc_restart() */
2892                 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2893                 return -EISDIR;
2894         }
2895         parent_hub = hdev_to_hub(parent_hdev);
2896
2897         set_bit(port1, parent_hub->busy_bits);
2898         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
2899
2900                 /* ep0 maxpacket size may change; let the HCD know about it.
2901                  * Other endpoints will be handled by re-enumeration. */
2902                 ep0_reinit(udev);
2903                 ret = hub_port_init(parent_hub, udev, port1, i);
2904                 if (ret >= 0)
2905                         break;
2906         }
2907         clear_bit(port1, parent_hub->busy_bits);
2908         if (!parent_hdev->parent && !parent_hub->busy_bits[0])
2909                 usb_enable_root_hub_irq(parent_hdev->bus);
2910
2911         if (ret < 0)
2912                 goto re_enumerate;
2913
2914         /* Device might have changed firmware (DFU or similar) */
2915         if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
2916                         || config_descriptors_changed (udev)) {
2917                 dev_info(&udev->dev, "device firmware changed\n");
2918                 udev->descriptor = descriptor;  /* for disconnect() calls */
2919                 goto re_enumerate;
2920         }
2921
2922         if (!udev->actconfig)
2923                 goto done;
2924
2925         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2926                         USB_REQ_SET_CONFIGURATION, 0,
2927                         udev->actconfig->desc.bConfigurationValue, 0,
2928                         NULL, 0, USB_CTRL_SET_TIMEOUT);
2929         if (ret < 0) {
2930                 dev_err(&udev->dev,
2931                         "can't restore configuration #%d (error=%d)\n",
2932                         udev->actconfig->desc.bConfigurationValue, ret);
2933                 goto re_enumerate;
2934         }
2935         usb_set_device_state(udev, USB_STATE_CONFIGURED);
2936
2937         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
2938                 struct usb_interface *intf = udev->actconfig->interface[i];
2939                 struct usb_interface_descriptor *desc;
2940
2941                 /* set_interface resets host side toggle even
2942                  * for altsetting zero.  the interface may have no driver.
2943                  */
2944                 desc = &intf->cur_altsetting->desc;
2945                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
2946                         desc->bAlternateSetting);
2947                 if (ret < 0) {
2948                         dev_err(&udev->dev, "failed to restore interface %d "
2949                                 "altsetting %d (error=%d)\n",
2950                                 desc->bInterfaceNumber,
2951                                 desc->bAlternateSetting,
2952                                 ret);
2953                         goto re_enumerate;
2954                 }
2955         }
2956
2957 done:
2958         return 0;
2959
2960 re_enumerate:
2961         hub_port_logical_disconnect(parent_hub, port1);
2962         return -ENODEV;
2963 }
2964 EXPORT_SYMBOL(usb_reset_device);
2965
2966 /**
2967  * usb_reset_composite_device - warn interface drivers and perform a USB port reset
2968  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2969  * @iface: interface bound to the driver making the request (optional)
2970  *
2971  * Warns all drivers bound to registered interfaces (using their pre_reset
2972  * method), performs the port reset, and then lets the drivers know that
2973  * the reset is over (using their post_reset method).
2974  *
2975  * Return value is the same as for usb_reset_device().
2976  *
2977  * The caller must own the device lock.  For example, it's safe to use
2978  * this from a driver probe() routine after downloading new firmware.
2979  * For calls that might not occur during probe(), drivers should lock
2980  * the device using usb_lock_device_for_reset().
2981  *
2982  * The interface locks are acquired during the pre_reset stage and released
2983  * during the post_reset stage.  However if iface is not NULL and is
2984  * currently being probed, we assume that the caller already owns its
2985  * lock.
2986  */
2987 int usb_reset_composite_device(struct usb_device *udev,
2988                 struct usb_interface *iface)
2989 {
2990         int ret;
2991         struct usb_host_config *config = udev->actconfig;
2992
2993         if (udev->state == USB_STATE_NOTATTACHED ||
2994                         udev->state == USB_STATE_SUSPENDED) {
2995                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2996                                 udev->state);
2997                 return -EINVAL;
2998         }
2999
3000         /* Prevent autosuspend during the reset */
3001         usb_autoresume_device(udev, 1);
3002
3003         if (iface && iface->condition != USB_INTERFACE_BINDING)
3004                 iface = NULL;
3005
3006         if (config) {
3007                 int i;
3008                 struct usb_interface *cintf;
3009                 struct usb_driver *drv;
3010
3011                 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
3012                         cintf = config->interface[i];
3013                         if (cintf != iface)
3014                                 down(&cintf->dev.sem);
3015                         if (device_is_registered(&cintf->dev) &&
3016                                         cintf->dev.driver) {
3017                                 drv = to_usb_driver(cintf->dev.driver);
3018                                 if (drv->pre_reset)
3019                                         (drv->pre_reset)(cintf);
3020                         }
3021                 }
3022         }
3023
3024         ret = usb_reset_device(udev);
3025
3026         if (config) {
3027                 int i;
3028                 struct usb_interface *cintf;
3029                 struct usb_driver *drv;
3030
3031                 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
3032                         cintf = config->interface[i];
3033                         if (device_is_registered(&cintf->dev) &&
3034                                         cintf->dev.driver) {
3035                                 drv = to_usb_driver(cintf->dev.driver);
3036                                 if (drv->post_reset)
3037                                         (drv->post_reset)(cintf);
3038                         }
3039                         if (cintf != iface)
3040                                 up(&cintf->dev.sem);
3041                 }
3042         }
3043
3044         usb_autosuspend_device(udev, 1);
3045         return ret;
3046 }
3047 EXPORT_SYMBOL(usb_reset_composite_device);