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/config.h>
  12 #ifdef CONFIG_USB_DEBUG
  13         #define DEBUG
  14 #else
  15         #undef DEBUG
  16 #endif
  17 #include <linux/kernel.h>
  18 #include <linux/errno.h>
  19 #include <linux/module.h>
  20 #include <linux/moduleparam.h>
  21 #include <linux/completion.h>
  22 #include <linux/sched.h>
  23 #include <linux/list.h>
  24 #include <linux/slab.h>
  25 #include <linux/smp_lock.h>
  26 #include <linux/ioctl.h>
  27 #include <linux/usb.h>
  28 #include <linux/usbdevice_fs.h>
  29 #include <linux/kthread.h>
  30
  31 #include <asm/semaphore.h>
  32 #include <asm/uaccess.h>
  33 #include <asm/byteorder.h>
  34
  35 #include "usb.h"
  36 #include "hcd.h"
  37 #include "hub.h"
  38
  39 /* Protect struct usb_device->state and ->children members
  40  * Note: Both are also protected by ->serialize, except that ->state can
  41  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
  42 static DEFINE_SPINLOCK(device_state_lock);
  43
  44 /* khubd's worklist and its lock */
  45 static DEFINE_SPINLOCK(hub_event_lock);
  46 static LIST_HEAD(hub_event_list);       /* List of hubs needing servicing */
  47
  48 /* Wakes up khubd */
  49 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
  50
  51 static struct task_struct *khubd_task;
  52
  53 /* cycle leds on hubs that aren't blinking for attention */
  54 static int blinkenlights = 0;
  55 module_param (blinkenlights, bool, S_IRUGO);
  56 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
  57
  58 /*
  59  * As of 2.6.10 we introduce a new USB device initialization scheme which
  60  * closely resembles the way Windows works.  Hopefully it will be compatible
  61  * with a wider range of devices than the old scheme.  However some previously
  62  * working devices may start giving rise to "device not accepting address"
  63  * errors; if that happens the user can try the old scheme by adjusting the
  64  * following module parameters.
  65  *
  66  * For maximum flexibility there are two boolean parameters to control the
  67  * hub driver's behavior.  On the first initialization attempt, if the
  68  * "old_scheme_first" parameter is set then the old scheme will be used,
  69  * otherwise the new scheme is used.  If that fails and "use_both_schemes"
  70  * is set, then the driver will make another attempt, using the other scheme.
  71  */
  72 static int old_scheme_first = 0;
  73 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
  74 MODULE_PARM_DESC(old_scheme_first,
  75                  "start with the old device initialization scheme");
  76
  77 static int use_both_schemes = 1;
  78 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
  79 MODULE_PARM_DESC(use_both_schemes,
  80                 "try the other device initialization scheme if the "
  81                 "first one fails");
  82
  83
  84 #ifdef  DEBUG
  85 static inline char *portspeed (int portstatus)
  86 {
  87         if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
  88                 return "480 Mb/s";
  89         else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
  90                 return "1.5 Mb/s";
  91         else
  92                 return "12 Mb/s";
  93 }
  94 #endif
  95
  96 /* Note that hdev or one of its children must be locked! */
  97 static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
  98 {
  99         return usb_get_intfdata(hdev->actconfig->interface[0]);
 100 }
 101
 102 /* USB 2.0 spec Section 11.24.4.5 */
 103 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
 104 {
 105         int i, ret;
 106
 107         for (i = 0; i < 3; i++) {
 108                 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 109                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
 110                         USB_DT_HUB << 8, 0, data, size,
 111                         USB_CTRL_GET_TIMEOUT);
 112                 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
 113                         return ret;
 114         }
 115         return -EINVAL;
 116 }
 117
 118 /*
 119  * USB 2.0 spec Section 11.24.2.1
 120  */
 121 static int clear_hub_feature(struct usb_device *hdev, int feature)
 122 {
 123         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 124                 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
 125 }
 126
 127 /*
 128  * USB 2.0 spec Section 11.24.2.2
 129  */
 130 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
 131 {
 132         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 133                 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
 134                 NULL, 0, 1000);
 135 }
 136
 137 /*
 138  * USB 2.0 spec Section 11.24.2.13
 139  */
 140 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
 141 {
 142         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 143                 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
 144                 NULL, 0, 1000);
 145 }
 146
 147 /*
 148  * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
 149  * for info about using port indicators
 150  */
 151 static void set_port_led(
 152         struct usb_hub *hub,
 153         int port1,
 154         int selector
 155 )
 156 {
 157         int status = set_port_feature(hub->hdev, (selector << 8) | port1,
 158                         USB_PORT_FEAT_INDICATOR);
 159         if (status < 0)
 160                 dev_dbg (hub->intfdev,
 161                         "port %d indicator %s status %d\n",
 162                         port1,
 163                         ({ char *s; switch (selector) {
 164                         case HUB_LED_AMBER: s = "amber"; break;
 165                         case HUB_LED_GREEN: s = "green"; break;
 166                         case HUB_LED_OFF: s = "off"; break;
 167                         case HUB_LED_AUTO: s = "auto"; break;
 168                         default: s = "??"; break;
 169                         }; s; }),
 170                         status);
 171 }
 172
 173 #define LED_CYCLE_PERIOD        ((2*HZ)/3)
 174
 175 static void led_work (void *__hub)
 176 {
 177         struct usb_hub          *hub = __hub;
 178         struct usb_device       *hdev = hub->hdev;
 179         unsigned                i;
 180         unsigned                changed = 0;
 181         int                     cursor = -1;
 182
 183         if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
 184                 return;
 185
 186         for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
 187                 unsigned        selector, mode;
 188
 189                 /* 30%-50% duty cycle */
 190
 191                 switch (hub->indicator[i]) {
 192                 /* cycle marker */
 193                 case INDICATOR_CYCLE:
 194                         cursor = i;
 195                         selector = HUB_LED_AUTO;
 196                         mode = INDICATOR_AUTO;
 197                         break;
 198                 /* blinking green = sw attention */
 199                 case INDICATOR_GREEN_BLINK:
 200                         selector = HUB_LED_GREEN;
 201                         mode = INDICATOR_GREEN_BLINK_OFF;
 202                         break;
 203                 case INDICATOR_GREEN_BLINK_OFF:
 204                         selector = HUB_LED_OFF;
 205                         mode = INDICATOR_GREEN_BLINK;
 206                         break;
 207                 /* blinking amber = hw attention */
 208                 case INDICATOR_AMBER_BLINK:
 209                         selector = HUB_LED_AMBER;
 210                         mode = INDICATOR_AMBER_BLINK_OFF;
 211                         break;
 212                 case INDICATOR_AMBER_BLINK_OFF:
 213                         selector = HUB_LED_OFF;
 214                         mode = INDICATOR_AMBER_BLINK;
 215                         break;
 216                 /* blink green/amber = reserved */
 217                 case INDICATOR_ALT_BLINK:
 218                         selector = HUB_LED_GREEN;
 219                         mode = INDICATOR_ALT_BLINK_OFF;
 220                         break;
 221                 case INDICATOR_ALT_BLINK_OFF:
 222                         selector = HUB_LED_AMBER;
 223                         mode = INDICATOR_ALT_BLINK;
 224                         break;
 225                 default:
 226                         continue;
 227                 }
 228                 if (selector != HUB_LED_AUTO)
 229                         changed = 1;
 230                 set_port_led(hub, i + 1, selector);
 231                 hub->indicator[i] = mode;
 232         }
 233         if (!changed && blinkenlights) {
 234                 cursor++;
 235                 cursor %= hub->descriptor->bNbrPorts;
 236                 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
 237                 hub->indicator[cursor] = INDICATOR_CYCLE;
 238                 changed++;
 239         }
 240         if (changed)
 241                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 242 }
 243
 244 /* use a short timeout for hub/port status fetches */
 245 #define USB_STS_TIMEOUT         1000
 246 #define USB_STS_RETRIES         5
 247
 248 /*
 249  * USB 2.0 spec Section 11.24.2.6
 250  */
 251 static int get_hub_status(struct usb_device *hdev,
 252                 struct usb_hub_status *data)
 253 {
 254         int i, status = -ETIMEDOUT;
 255
 256         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
 257                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 258                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
 259                         data, sizeof(*data), USB_STS_TIMEOUT);
 260         }
 261         return status;
 262 }
 263
 264 /*
 265  * USB 2.0 spec Section 11.24.2.7
 266  */
 267 static int get_port_status(struct usb_device *hdev, int port1,
 268                 struct usb_port_status *data)
 269 {
 270         int i, status = -ETIMEDOUT;
 271
 272         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
 273                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 274                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
 275                         data, sizeof(*data), USB_STS_TIMEOUT);
 276         }
 277         return status;
 278 }
 279
 280 static void kick_khubd(struct usb_hub *hub)
 281 {
 282         unsigned long   flags;
 283
 284         spin_lock_irqsave(&hub_event_lock, flags);
 285         if (list_empty(&hub->event_list)) {
 286                 list_add_tail(&hub->event_list, &hub_event_list);
 287                 wake_up(&khubd_wait);
 288         }
 289         spin_unlock_irqrestore(&hub_event_lock, flags);
 290 }
 291
 292 void usb_kick_khubd(struct usb_device *hdev)
 293 {
 294         kick_khubd(hdev_to_hub(hdev));
 295 }
 296
 297
 298 /* completion function, fires on port status changes and various faults */
 299 static void hub_irq(struct urb *urb, struct pt_regs *regs)
 300 {
 301         struct usb_hub *hub = (struct usb_hub *)urb->context;
 302         int status;
 303         int i;
 304         unsigned long bits;
 305
 306         switch (urb->status) {
 307         case -ENOENT:           /* synchronous unlink */
 308         case -ECONNRESET:       /* async unlink */
 309         case -ESHUTDOWN:        /* hardware going away */
 310                 return;
 311
 312         default:                /* presumably an error */
 313                 /* Cause a hub reset after 10 consecutive errors */
 314                 dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
 315                 if ((++hub->nerrors < 10) || hub->error)
 316                         goto resubmit;
 317                 hub->error = urb->status;
 318                 /* FALL THROUGH */
 319
 320         /* let khubd handle things */
 321         case 0:                 /* we got data:  port status changed */
 322                 bits = 0;
 323                 for (i = 0; i < urb->actual_length; ++i)
 324                         bits |= ((unsigned long) ((*hub->buffer)[i]))
 325                                         << (i*8);
 326                 hub->event_bits[0] = bits;
 327                 break;
 328         }
 329
 330         hub->nerrors = 0;
 331
 332         /* Something happened, let khubd figure it out */
 333         kick_khubd(hub);
 334
 335 resubmit:
 336         if (hub->quiescing)
 337                 return;
 338
 339         if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
 340                         && status != -ENODEV && status != -EPERM)
 341                 dev_err (hub->intfdev, "resubmit --> %d\n", status);
 342 }
 343
 344 /* USB 2.0 spec Section 11.24.2.3 */
 345 static inline int
 346 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
 347 {
 348         return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 349                                HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
 350                                tt, NULL, 0, 1000);
 351 }
 352
 353 /*
 354  * enumeration blocks khubd for a long time. we use keventd instead, since
 355  * long blocking there is the exception, not the rule.  accordingly, HCDs
 356  * talking to TTs must queue control transfers (not just bulk and iso), so
 357  * both can talk to the same hub concurrently.
 358  */
 359 static void hub_tt_kevent (void *arg)
 360 {
 361         struct usb_hub          *hub = arg;
 362         unsigned long           flags;
 363
 364         spin_lock_irqsave (&hub->tt.lock, flags);
 365         while (!list_empty (&hub->tt.clear_list)) {
 366                 struct list_head        *temp;
 367                 struct usb_tt_clear     *clear;
 368                 struct usb_device       *hdev = hub->hdev;
 369                 int                     status;
 370
 371                 temp = hub->tt.clear_list.next;
 372                 clear = list_entry (temp, struct usb_tt_clear, clear_list);
 373                 list_del (&clear->clear_list);
 374
 375                 /* drop lock so HCD can concurrently report other TT errors */
 376                 spin_unlock_irqrestore (&hub->tt.lock, flags);
 377                 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
 378                 spin_lock_irqsave (&hub->tt.lock, flags);
 379
 380                 if (status)
 381                         dev_err (&hdev->dev,
 382                                 "clear tt %d (%04x) error %d\n",
 383                                 clear->tt, clear->devinfo, status);
 384                 kfree(clear);
 385         }
 386         spin_unlock_irqrestore (&hub->tt.lock, flags);
 387 }
 388
 389 /**
 390  * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
 391  * @udev: the device whose split transaction failed
 392  * @pipe: identifies the endpoint of the failed transaction
 393  *
 394  * High speed HCDs use this to tell the hub driver that some split control or
 395  * bulk transaction failed in a way that requires clearing internal state of
 396  * a transaction translator.  This is normally detected (and reported) from
 397  * interrupt context.
 398  *
 399  * It may not be possible for that hub to handle additional full (or low)
 400  * speed transactions until that state is fully cleared out.
 401  */
 402 void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
 403 {
 404         struct usb_tt           *tt = udev->tt;
 405         unsigned long           flags;
 406         struct usb_tt_clear     *clear;
 407
 408         /* we've got to cope with an arbitrary number of pending TT clears,
 409          * since each TT has "at least two" buffers that can need it (and
 410          * there can be many TTs per hub).  even if they're uncommon.
 411          */
 412         if ((clear = kmalloc (sizeof *clear, SLAB_ATOMIC)) == NULL) {
 413                 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
 414                 /* FIXME recover somehow ... RESET_TT? */
 415                 return;
 416         }
 417
 418         /* info that CLEAR_TT_BUFFER needs */
 419         clear->tt = tt->multi ? udev->ttport : 1;
 420         clear->devinfo = usb_pipeendpoint (pipe);
 421         clear->devinfo |= udev->devnum << 4;
 422         clear->devinfo |= usb_pipecontrol (pipe)
 423                         ? (USB_ENDPOINT_XFER_CONTROL << 11)
 424                         : (USB_ENDPOINT_XFER_BULK << 11);
 425         if (usb_pipein (pipe))
 426                 clear->devinfo |= 1 << 15;
 427
 428         /* tell keventd to clear state for this TT */
 429         spin_lock_irqsave (&tt->lock, flags);
 430         list_add_tail (&clear->clear_list, &tt->clear_list);
 431         schedule_work (&tt->kevent);
 432         spin_unlock_irqrestore (&tt->lock, flags);
 433 }
 434
 435 static void hub_power_on(struct usb_hub *hub)
 436 {
 437         int port1;
 438
 439         /* if hub supports power switching, enable power on each port */
 440         if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_LPSM) < 2) {
 441                 dev_dbg(hub->intfdev, "enabling power on all ports\n");
 442                 for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
 443                         set_port_feature(hub->hdev, port1,
 444                                         USB_PORT_FEAT_POWER);
 445         }
 446
 447         /* Wait for power to be enabled */
 448         msleep(hub->descriptor->bPwrOn2PwrGood * 2);
 449 }
 450
 451 static void hub_quiesce(struct usb_hub *hub)
 452 {
 453         /* stop khubd and related activity */
 454         hub->quiescing = 1;
 455         usb_kill_urb(hub->urb);
 456         if (hub->has_indicators)
 457                 cancel_delayed_work(&hub->leds);
 458         if (hub->has_indicators || hub->tt.hub)
 459                 flush_scheduled_work();
 460 }
 461
 462 static void hub_activate(struct usb_hub *hub)
 463 {
 464         int     status;
 465
 466         hub->quiescing = 0;
 467         hub->activating = 1;
 468         status = usb_submit_urb(hub->urb, GFP_NOIO);
 469         if (status < 0)
 470                 dev_err(hub->intfdev, "activate --> %d\n", status);
 471         if (hub->has_indicators && blinkenlights)
 472                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 473
 474         /* scan all ports ASAP */
 475         kick_khubd(hub);
 476 }
 477
 478 static int hub_hub_status(struct usb_hub *hub,
 479                 u16 *status, u16 *change)
 480 {
 481         int ret;
 482
 483         ret = get_hub_status(hub->hdev, &hub->status->hub);
 484         if (ret < 0)
 485                 dev_err (hub->intfdev,
 486                         "%s failed (err = %d)\n", __FUNCTION__, ret);
 487         else {
 488                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
 489                 *change = le16_to_cpu(hub->status->hub.wHubChange);
 490                 ret = 0;
 491         }
 492         return ret;
 493 }
 494
 495 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
 496 {
 497         struct usb_device *hdev = hub->hdev;
 498         int ret;
 499
 500         if (hdev->children[port1-1] && set_state) {
 501                 usb_set_device_state(hdev->children[port1-1],
 502                                 USB_STATE_NOTATTACHED);
 503         }
 504         ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
 505         if (ret)
 506                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
 507                         port1, ret);
 508
 509         return ret;
 510 }
 511
 512 static int hub_configure(struct usb_hub *hub,
 513         struct usb_endpoint_descriptor *endpoint)
 514 {
 515         struct usb_device *hdev = hub->hdev;
 516         struct device *hub_dev = hub->intfdev;
 517         u16 hubstatus, hubchange;
 518         unsigned int pipe;
 519         int maxp, ret;
 520         char *message;
 521
 522         hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
 523                         &hub->buffer_dma);
 524         if (!hub->buffer) {
 525                 message = "can't allocate hub irq buffer";
 526                 ret = -ENOMEM;
 527                 goto fail;
 528         }
 529
 530         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
 531         if (!hub->status) {
 532                 message = "can't kmalloc hub status buffer";
 533                 ret = -ENOMEM;
 534                 goto fail;
 535         }
 536
 537         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
 538         if (!hub->descriptor) {
 539                 message = "can't kmalloc hub descriptor";
 540                 ret = -ENOMEM;
 541                 goto fail;
 542         }
 543
 544         /* Request the entire hub descriptor.
 545          * hub->descriptor can handle USB_MAXCHILDREN ports,
 546          * but the hub can/will return fewer bytes here.
 547          */
 548         ret = get_hub_descriptor(hdev, hub->descriptor,
 549                         sizeof(*hub->descriptor));
 550         if (ret < 0) {
 551                 message = "can't read hub descriptor";
 552                 goto fail;
 553         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
 554                 message = "hub has too many ports!";
 555                 ret = -ENODEV;
 556                 goto fail;
 557         }
 558
 559         hdev->maxchild = hub->descriptor->bNbrPorts;
 560         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
 561                 (hdev->maxchild == 1) ? "" : "s");
 562
 563         le16_to_cpus(&hub->descriptor->wHubCharacteristics);
 564
 565         if (hub->descriptor->wHubCharacteristics & HUB_CHAR_COMPOUND) {
 566                 int     i;
 567                 char    portstr [USB_MAXCHILDREN + 1];
 568
 569                 for (i = 0; i < hdev->maxchild; i++)
 570                         portstr[i] = hub->descriptor->DeviceRemovable
 571                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
 572                                 ? 'F' : 'R';
 573                 portstr[hdev->maxchild] = 0;
 574                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
 575         } else
 576                 dev_dbg(hub_dev, "standalone hub\n");
 577
 578         switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_LPSM) {
 579                 case 0x00:
 580                         dev_dbg(hub_dev, "ganged power switching\n");
 581                         break;
 582                 case 0x01:
 583                         dev_dbg(hub_dev, "individual port power switching\n");
 584                         break;
 585                 case 0x02:
 586                 case 0x03:
 587                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
 588                         break;
 589         }
 590
 591         switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) {
 592                 case 0x00:
 593                         dev_dbg(hub_dev, "global over-current protection\n");
 594                         break;
 595                 case 0x08:
 596                         dev_dbg(hub_dev, "individual port over-current protection\n");
 597                         break;
 598                 case 0x10:
 599                 case 0x18:
 600                         dev_dbg(hub_dev, "no over-current protection\n");
 601                         break;
 602         }
 603
 604         spin_lock_init (&hub->tt.lock);
 605         INIT_LIST_HEAD (&hub->tt.clear_list);
 606         INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub);
 607         switch (hdev->descriptor.bDeviceProtocol) {
 608                 case 0:
 609                         break;
 610                 case 1:
 611                         dev_dbg(hub_dev, "Single TT\n");
 612                         hub->tt.hub = hdev;
 613                         break;
 614                 case 2:
 615                         ret = usb_set_interface(hdev, 0, 1);
 616                         if (ret == 0) {
 617                                 dev_dbg(hub_dev, "TT per port\n");
 618                                 hub->tt.multi = 1;
 619                         } else
 620                                 dev_err(hub_dev, "Using single TT (err %d)\n",
 621                                         ret);
 622                         hub->tt.hub = hdev;
 623                         break;
 624                 default:
 625                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
 626                                 hdev->descriptor.bDeviceProtocol);
 627                         break;
 628         }
 629
 630         switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_TTTT) {
 631                 case 0x00:
 632                         if (hdev->descriptor.bDeviceProtocol != 0)
 633                                 dev_dbg(hub_dev, "TT requires at most 8 FS bit times\n");
 634                         break;
 635                 case 0x20:
 636                         dev_dbg(hub_dev, "TT requires at most 16 FS bit times\n");
 637                         break;
 638                 case 0x40:
 639                         dev_dbg(hub_dev, "TT requires at most 24 FS bit times\n");
 640                         break;
 641                 case 0x60:
 642                         dev_dbg(hub_dev, "TT requires at most 32 FS bit times\n");
 643                         break;
 644         }
 645
 646         /* probe() zeroes hub->indicator[] */
 647         if (hub->descriptor->wHubCharacteristics & HUB_CHAR_PORTIND) {
 648                 hub->has_indicators = 1;
 649                 dev_dbg(hub_dev, "Port indicators are supported\n");
 650         }
 651
 652         dev_dbg(hub_dev, "power on to power good time: %dms\n",
 653                 hub->descriptor->bPwrOn2PwrGood * 2);
 654
 655         /* power budgeting mostly matters with bus-powered hubs,
 656          * and battery-powered root hubs (may provide just 8 mA).
 657          */
 658         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
 659         if (ret < 0) {
 660                 message = "can't get hub status";
 661                 goto fail;
 662         }
 663         le16_to_cpus(&hubstatus);
 664         if (hdev == hdev->bus->root_hub) {
 665                 struct usb_hcd *hcd =
 666                                 container_of(hdev->bus, struct usb_hcd, self);
 667
 668                 hub->power_budget = min(500u, hcd->power_budget) / 2;
 669         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
 670                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
 671                         hub->descriptor->bHubContrCurrent);
 672                 hub->power_budget = (501 - hub->descriptor->bHubContrCurrent)
 673                                         / 2;
 674         }
 675         if (hub->power_budget)
 676                 dev_dbg(hub_dev, "%dmA bus power budget for children\n",
 677                         hub->power_budget * 2);
 678
 679
 680         ret = hub_hub_status(hub, &hubstatus, &hubchange);
 681         if (ret < 0) {
 682                 message = "can't get hub status";
 683                 goto fail;
 684         }
 685
 686         /* local power status reports aren't always correct */
 687         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
 688                 dev_dbg(hub_dev, "local power source is %s\n",
 689                         (hubstatus & HUB_STATUS_LOCAL_POWER)
 690                         ? "lost (inactive)" : "good");
 691
 692         if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) == 0)
 693                 dev_dbg(hub_dev, "%sover-current condition exists\n",
 694                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
 695
 696         /* set up the interrupt endpoint */
 697         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
 698         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
 699
 700         if (maxp > sizeof(*hub->buffer))
 701                 maxp = sizeof(*hub->buffer);
 702
 703         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
 704         if (!hub->urb) {
 705                 message = "couldn't allocate interrupt urb";
 706                 ret = -ENOMEM;
 707                 goto fail;
 708         }
 709
 710         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
 711                 hub, endpoint->bInterval);
 712         hub->urb->transfer_dma = hub->buffer_dma;
 713         hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 714
 715         /* maybe cycle the hub leds */
 716         if (hub->has_indicators && blinkenlights)
 717                 hub->indicator [0] = INDICATOR_CYCLE;
 718
 719         hub_power_on(hub);
 720         hub_activate(hub);
 721         return 0;
 722
 723 fail:
 724         dev_err (hub_dev, "config failed, %s (err %d)\n",
 725                         message, ret);
 726         /* hub_disconnect() frees urb and descriptor */
 727         return ret;
 728 }
 729
 730 static unsigned highspeed_hubs;
 731
 732 /* Called after the hub driver is unbound from a hub with children */
 733 static void hub_remove_children_work(void *__hub)
 734 {
 735         struct usb_hub          *hub = __hub;
 736         struct usb_device       *hdev = hub->hdev;
 737         int                     i;
 738
 739         kfree(hub);
 740
 741         usb_lock_device(hdev);
 742         for (i = 0; i < hdev->maxchild; ++i) {
 743                 if (hdev->children[i])
 744                         usb_disconnect(&hdev->children[i]);
 745         }
 746         usb_unlock_device(hdev);
 747         usb_put_dev(hdev);
 748 }
 749
 750 static void hub_disconnect(struct usb_interface *intf)
 751 {
 752         struct usb_hub *hub = usb_get_intfdata (intf);
 753         struct usb_device *hdev;
 754         int n, port1;
 755
 756         usb_set_intfdata (intf, NULL);
 757         hdev = hub->hdev;
 758
 759         if (hdev->speed == USB_SPEED_HIGH)
 760                 highspeed_hubs--;
 761
 762         hub_quiesce(hub);
 763         usb_free_urb(hub->urb);
 764         hub->urb = NULL;
 765
 766         spin_lock_irq(&hub_event_lock);
 767         list_del_init(&hub->event_list);
 768         spin_unlock_irq(&hub_event_lock);
 769
 770         kfree(hub->descriptor);
 771         hub->descriptor = NULL;
 772
 773         kfree(hub->status);
 774         hub->status = NULL;
 775
 776         if (hub->buffer) {
 777                 usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
 778                                 hub->buffer_dma);
 779                 hub->buffer = NULL;
 780         }
 781
 782         /* If there are any children then this is an unbind only, not a
 783          * physical disconnection.  The active ports must be disabled
 784          * and later on we must call usb_disconnect().  We can't call
 785          * it now because we may not hold the hub's device lock.
 786          */
 787         n = 0;
 788         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
 789                 if (hdev->children[port1 - 1]) {
 790                         ++n;
 791                         hub_port_disable(hub, port1, 1);
 792                 }
 793         }
 794
 795         if (n == 0)
 796                 kfree(hub);
 797         else {
 798                 /* Reuse the hub->leds work_struct for our own purposes */
 799                 INIT_WORK(&hub->leds, hub_remove_children_work, hub);
 800                 schedule_work(&hub->leds);
 801                 usb_get_dev(hdev);
 802         }
 803 }
 804
 805 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
 806 {
 807         struct usb_host_interface *desc;
 808         struct usb_endpoint_descriptor *endpoint;
 809         struct usb_device *hdev;
 810         struct usb_hub *hub;
 811
 812         desc = intf->cur_altsetting;
 813         hdev = interface_to_usbdev(intf);
 814
 815         /* Some hubs have a subclass of 1, which AFAICT according to the */
 816         /*  specs is not defined, but it works */
 817         if ((desc->desc.bInterfaceSubClass != 0) &&
 818             (desc->desc.bInterfaceSubClass != 1)) {
 819 descriptor_error:
 820                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
 821                 return -EIO;
 822         }
 823
 824         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
 825         if (desc->desc.bNumEndpoints != 1)
 826                 goto descriptor_error;
 827
 828         endpoint = &desc->endpoint[0].desc;
 829
 830         /* Output endpoint? Curiouser and curiouser.. */
 831         if (!(endpoint->bEndpointAddress & USB_DIR_IN))
 832                 goto descriptor_error;
 833
 834         /* If it's not an interrupt endpoint, we'd better punt! */
 835         if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
 836                         != USB_ENDPOINT_XFER_INT)
 837                 goto descriptor_error;
 838
 839         /* We found a hub */
 840         dev_info (&intf->dev, "USB hub found\n");
 841
 842         hub = kmalloc(sizeof(*hub), GFP_KERNEL);
 843         if (!hub) {
 844                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
 845                 return -ENOMEM;
 846         }
 847
 848         memset(hub, 0, sizeof(*hub));
 849
 850         INIT_LIST_HEAD(&hub->event_list);
 851         hub->intfdev = &intf->dev;
 852         hub->hdev = hdev;
 853         INIT_WORK(&hub->leds, led_work, hub);
 854
 855         usb_set_intfdata (intf, hub);
 856
 857         if (hdev->speed == USB_SPEED_HIGH)
 858                 highspeed_hubs++;
 859
 860         if (hub_configure(hub, endpoint) >= 0)
 861                 return 0;
 862
 863         hub_disconnect (intf);
 864         return -ENODEV;
 865 }
 866
 867 static int
 868 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
 869 {
 870         struct usb_device *hdev = interface_to_usbdev (intf);
 871
 872         /* assert ifno == 0 (part of hub spec) */
 873         switch (code) {
 874         case USBDEVFS_HUB_PORTINFO: {
 875                 struct usbdevfs_hub_portinfo *info = user_data;
 876                 int i;
 877
 878                 spin_lock_irq(&device_state_lock);
 879                 if (hdev->devnum <= 0)
 880                         info->nports = 0;
 881                 else {
 882                         info->nports = hdev->maxchild;
 883                         for (i = 0; i < info->nports; i++) {
 884                                 if (hdev->children[i] == NULL)
 885                                         info->port[i] = 0;
 886                                 else
 887                                         info->port[i] =
 888                                                 hdev->children[i]->devnum;
 889                         }
 890                 }
 891                 spin_unlock_irq(&device_state_lock);
 892
 893                 return info->nports + 1;
 894                 }
 895
 896         default:
 897                 return -ENOSYS;
 898         }
 899 }
 900
 901 /* caller has locked the hub device */
 902 static void hub_pre_reset(struct usb_hub *hub)
 903 {
 904         struct usb_device *hdev = hub->hdev;
 905         int i;
 906
 907         for (i = 0; i < hdev->maxchild; ++i) {
 908                 if (hdev->children[i])
 909                         usb_disconnect(&hdev->children[i]);
 910         }
 911         hub_quiesce(hub);
 912 }
 913
 914 /* caller has locked the hub device */
 915 static void hub_post_reset(struct usb_hub *hub)
 916 {
 917         hub_activate(hub);
 918         hub_power_on(hub);
 919 }
 920
 921
 922 /* grab device/port lock, returning index of that port (zero based).
 923  * protects the upstream link used by this device from concurrent
 924  * tree operations like suspend, resume, reset, and disconnect, which
 925  * apply to everything downstream of a given port.
 926  */
 927 static int locktree(struct usb_device *udev)
 928 {
 929         int                     t;
 930         struct usb_device       *hdev;
 931
 932         if (!udev)
 933                 return -ENODEV;
 934
 935         /* root hub is always the first lock in the series */
 936         hdev = udev->parent;
 937         if (!hdev) {
 938                 usb_lock_device(udev);
 939                 return 0;
 940         }
 941
 942         /* on the path from root to us, lock everything from
 943          * top down, dropping parent locks when not needed
 944          */
 945         t = locktree(hdev);
 946         if (t < 0)
 947                 return t;
 948         for (t = 0; t < hdev->maxchild; t++) {
 949                 if (hdev->children[t] == udev) {
 950                         /* everything is fail-fast once disconnect
 951                          * processing starts
 952                          */
 953                         if (udev->state == USB_STATE_NOTATTACHED)
 954                                 break;
 955
 956                         /* when everyone grabs locks top->bottom,
 957                          * non-overlapping work may be concurrent
 958                          */
 959                         down(&udev->serialize);
 960                         up(&hdev->serialize);
 961                         return t + 1;
 962                 }
 963         }
 964         usb_unlock_device(hdev);
 965         return -ENODEV;
 966 }
 967
 968 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
 969 {
 970         int i;
 971
 972         for (i = 0; i < udev->maxchild; ++i) {
 973                 if (udev->children[i])
 974                         recursively_mark_NOTATTACHED(udev->children[i]);
 975         }
 976         udev->state = USB_STATE_NOTATTACHED;
 977 }
 978
 979 /**
 980  * usb_set_device_state - change a device's current state (usbcore, hcds)
 981  * @udev: pointer to device whose state should be changed
 982  * @new_state: new state value to be stored
 983  *
 984  * udev->state is _not_ fully protected by the device lock.  Although
 985  * most transitions are made only while holding the lock, the state can
 986  * can change to USB_STATE_NOTATTACHED at almost any time.  This
 987  * is so that devices can be marked as disconnected as soon as possible,
 988  * without having to wait for any semaphores to be released.  As a result,
 989  * all changes to any device's state must be protected by the
 990  * device_state_lock spinlock.
 991  *
 992  * Once a device has been added to the device tree, all changes to its state
 993  * should be made using this routine.  The state should _not_ be set directly.
 994  *
 995  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
 996  * Otherwise udev->state is set to new_state, and if new_state is
 997  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
 998  * to USB_STATE_NOTATTACHED.
 999  */
1000 void usb_set_device_state(struct usb_device *udev,
1001                 enum usb_device_state new_state)
1002 {
1003         unsigned long flags;
1004
1005         spin_lock_irqsave(&device_state_lock, flags);
1006         if (udev->state == USB_STATE_NOTATTACHED)
1007                 ;       /* do nothing */
1008         else if (new_state != USB_STATE_NOTATTACHED)
1009                 udev->state = new_state;
1010         else
1011                 recursively_mark_NOTATTACHED(udev);
1012         spin_unlock_irqrestore(&device_state_lock, flags);
1013 }
1014 EXPORT_SYMBOL(usb_set_device_state);
1015
1016
1017 static void choose_address(struct usb_device *udev)
1018 {
1019         int             devnum;
1020         struct usb_bus  *bus = udev->bus;
1021
1022         /* If khubd ever becomes multithreaded, this will need a lock */
1023
1024         /* Try to allocate the next devnum beginning at bus->devnum_next. */
1025         devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1026                         bus->devnum_next);
1027         if (devnum >= 128)
1028                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1029
1030         bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1031
1032         if (devnum < 128) {
1033                 set_bit(devnum, bus->devmap.devicemap);
1034                 udev->devnum = devnum;
1035         }
1036 }
1037
1038 static void release_address(struct usb_device *udev)
1039 {
1040         if (udev->devnum > 0) {
1041                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1042                 udev->devnum = -1;
1043         }
1044 }
1045
1046 /**
1047  * usb_disconnect - disconnect a device (usbcore-internal)
1048  * @pdev: pointer to device being disconnected
1049  * Context: !in_interrupt ()
1050  *
1051  * Something got disconnected. Get rid of it and all of its children.
1052  *
1053  * If *pdev is a normal device then the parent hub must already be locked.
1054  * If *pdev is a root hub then this routine will acquire the
1055  * usb_bus_list_lock on behalf of the caller.
1056  *
1057  * Only hub drivers (including virtual root hub drivers for host
1058  * controllers) should ever call this.
1059  *
1060  * This call is synchronous, and may not be used in an interrupt context.
1061  */
1062 void usb_disconnect(struct usb_device **pdev)
1063 {
1064         struct usb_device       *udev = *pdev;
1065         int                     i;
1066
1067         if (!udev) {
1068                 pr_debug ("%s nodev\n", __FUNCTION__);
1069                 return;
1070         }
1071
1072         /* mark the device as inactive, so any further urb submissions for
1073          * this device (and any of its children) will fail immediately.
1074          * this quiesces everyting except pending urbs.
1075          */
1076         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1077
1078         /* lock the bus list on behalf of HCDs unregistering their root hubs */
1079         if (!udev->parent) {
1080                 down(&usb_bus_list_lock);
1081                 usb_lock_device(udev);
1082         } else
1083                 down(&udev->serialize);
1084
1085         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1086
1087         /* Free up all the children before we remove this device */
1088         for (i = 0; i < USB_MAXCHILDREN; i++) {
1089                 if (udev->children[i])
1090                         usb_disconnect(&udev->children[i]);
1091         }
1092
1093         /* deallocate hcd/hardware state ... nuking all pending urbs and
1094          * cleaning up all state associated with the current configuration
1095          * so that the hardware is now fully quiesced.
1096          */
1097         usb_disable_device(udev, 0);
1098
1099         /* Free the device number, remove the /proc/bus/usb entry and
1100          * the sysfs attributes, and delete the parent's children[]
1101          * (or root_hub) pointer.
1102          */
1103         dev_dbg (&udev->dev, "unregistering device\n");
1104         release_address(udev);
1105         usbfs_remove_device(udev);
1106         usbdev_remove(udev);
1107         usb_remove_sysfs_dev_files(udev);
1108
1109         /* Avoid races with recursively_mark_NOTATTACHED() */
1110         spin_lock_irq(&device_state_lock);
1111         *pdev = NULL;
1112         spin_unlock_irq(&device_state_lock);
1113
1114         if (!udev->parent) {
1115                 usb_unlock_device(udev);
1116                 up(&usb_bus_list_lock);
1117         } else
1118                 up(&udev->serialize);
1119
1120         device_unregister(&udev->dev);
1121 }
1122
1123 static int choose_configuration(struct usb_device *udev)
1124 {
1125         int c, i;
1126
1127         /* NOTE: this should interact with hub power budgeting */
1128
1129         c = udev->config[0].desc.bConfigurationValue;
1130         if (udev->descriptor.bNumConfigurations != 1) {
1131                 for (i = 0; i < udev->descriptor.bNumConfigurations; i++) {
1132                         struct usb_interface_descriptor *desc;
1133
1134                         /* heuristic:  Linux is more likely to have class
1135                          * drivers, so avoid vendor-specific interfaces.
1136                          */
1137                         desc = &udev->config[i].intf_cache[0]
1138                                         ->altsetting->desc;
1139                         if (desc->bInterfaceClass == USB_CLASS_VENDOR_SPEC)
1140                                 continue;
1141                         /* COMM/2/all is CDC ACM, except 0xff is MSFT RNDIS.
1142                          * MSFT needs this to be the first config; never use
1143                          * it as the default unless Linux has host-side RNDIS.
1144                          * A second config would ideally be CDC-Ethernet, but
1145                          * may instead be the "vendor specific" CDC subset
1146                          * long used by ARM Linux for sa1100 or pxa255.
1147                          */
1148                         if (desc->bInterfaceClass == USB_CLASS_COMM
1149                                         && desc->bInterfaceSubClass == 2
1150                                         && desc->bInterfaceProtocol == 0xff) {
1151                                 c = udev->config[1].desc.bConfigurationValue;
1152                                 continue;
1153                         }
1154                         c = udev->config[i].desc.bConfigurationValue;
1155                         break;
1156                 }
1157                 dev_info(&udev->dev,
1158                         "configuration #%d chosen from %d choices\n",
1159                         c, udev->descriptor.bNumConfigurations);
1160         }
1161         return c;
1162 }
1163
1164 #ifdef DEBUG
1165 static void show_string(struct usb_device *udev, char *id, char *string)
1166 {
1167         if (!string)
1168                 return;
1169         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1170 }
1171
1172 #else
1173 static inline void show_string(struct usb_device *udev, char *id, char *string)
1174 {}
1175 #endif
1176
1177 static void get_string(struct usb_device *udev, char **string, int index)
1178 {
1179         char *buf;
1180
1181         if (!index)
1182                 return;
1183         buf = kmalloc(256, GFP_KERNEL);
1184         if (!buf)
1185                 return;
1186         if (usb_string(udev, index, buf, 256) > 0)
1187                 *string = buf;
1188         else
1189                 kfree(buf);
1190 }
1191
1192
1193 #ifdef  CONFIG_USB_OTG
1194 #include "otg_whitelist.h"
1195 #endif
1196
1197 /**
1198  * usb_new_device - perform initial device setup (usbcore-internal)
1199  * @udev: newly addressed device (in ADDRESS state)
1200  *
1201  * This is called with devices which have been enumerated, but not yet
1202  * configured.  The device descriptor is available, but not descriptors
1203  * for any device configuration.  The caller must have locked udev and
1204  * either the parent hub (if udev is a normal device) or else the
1205  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1206  * udev has already been installed, but udev is not yet visible through
1207  * sysfs or other filesystem code.
1208  *
1209  * Returns 0 for success (device is configured and listed, with its
1210  * interfaces, in sysfs); else a negative errno value.
1211  *
1212  * This call is synchronous, and may not be used in an interrupt context.
1213  *
1214  * Only the hub driver should ever call this; root hub registration
1215  * uses it indirectly.
1216  */
1217 int usb_new_device(struct usb_device *udev)
1218 {
1219         int err;
1220         int c;
1221
1222         err = usb_get_configuration(udev);
1223         if (err < 0) {
1224                 dev_err(&udev->dev, "can't read configurations, error %d\n",
1225                         err);
1226                 goto fail;
1227         }
1228
1229         /* read the standard strings and cache them if present */
1230         get_string(udev, &udev->product, udev->descriptor.iProduct);
1231         get_string(udev, &udev->manufacturer, udev->descriptor.iManufacturer);
1232         get_string(udev, &udev->serial, udev->descriptor.iSerialNumber);
1233
1234         /* Tell the world! */
1235         dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1236                         "SerialNumber=%d\n",
1237                         udev->descriptor.iManufacturer,
1238                         udev->descriptor.iProduct,
1239                         udev->descriptor.iSerialNumber);
1240         show_string(udev, "Product", udev->product);
1241         show_string(udev, "Manufacturer", udev->manufacturer);
1242         show_string(udev, "SerialNumber", udev->serial);
1243
1244 #ifdef  CONFIG_USB_OTG
1245         /*
1246          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1247          * to wake us after we've powered off VBUS; and HNP, switching roles
1248          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1249          */
1250         if (!udev->bus->is_b_host
1251                         && udev->config
1252                         && udev->parent == udev->bus->root_hub) {
1253                 struct usb_otg_descriptor       *desc = 0;
1254                 struct usb_bus                  *bus = udev->bus;
1255
1256                 /* descriptor may appear anywhere in config */
1257                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1258                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1259                                         USB_DT_OTG, (void **) &desc) == 0) {
1260                         if (desc->bmAttributes & USB_OTG_HNP) {
1261                                 unsigned                port1;
1262                                 struct usb_device       *root = udev->parent;
1263
1264                                 for (port1 = 1; port1 <= root->maxchild;
1265                                                 port1++) {
1266                                         if (root->children[port1-1] == udev)
1267                                                 break;
1268                                 }
1269
1270                                 dev_info(&udev->dev,
1271                                         "Dual-Role OTG device on %sHNP port\n",
1272                                         (port1 == bus->otg_port)
1273                                                 ? "" : "non-");
1274
1275                                 /* enable HNP before suspend, it's simpler */
1276                                 if (port1 == bus->otg_port)
1277                                         bus->b_hnp_enable = 1;
1278                                 err = usb_control_msg(udev,
1279                                         usb_sndctrlpipe(udev, 0),
1280                                         USB_REQ_SET_FEATURE, 0,
1281                                         bus->b_hnp_enable
1282                                                 ? USB_DEVICE_B_HNP_ENABLE
1283                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1284                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1285                                 if (err < 0) {
1286                                         /* OTG MESSAGE: report errors here,
1287                                          * customize to match your product.
1288                                          */
1289                                         dev_info(&udev->dev,
1290                                                 "can't set HNP mode; %d\n",
1291                                                 err);
1292                                         bus->b_hnp_enable = 0;
1293                                 }
1294                         }
1295                 }
1296         }
1297
1298         if (!is_targeted(udev)) {
1299
1300                 /* Maybe it can talk to us, though we can't talk to it.
1301                  * (Includes HNP test device.)
1302                  */
1303                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1304                         static int __usb_suspend_device (struct usb_device *,
1305                                                 int port1, pm_message_t state);
1306                         err = __usb_suspend_device(udev,
1307                                         udev->bus->otg_port,
1308                                         PMSG_SUSPEND);
1309                         if (err < 0)
1310                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1311                 }
1312                 err = -ENODEV;
1313                 goto fail;
1314         }
1315 #endif
1316
1317         /* put device-specific files into sysfs */
1318         err = device_add (&udev->dev);
1319         if (err) {
1320                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1321                 goto fail;
1322         }
1323         usb_create_sysfs_dev_files (udev);
1324
1325         /* choose and set the configuration. that registers the interfaces
1326          * with the driver core, and lets usb device drivers bind to them.
1327          */
1328         c = choose_configuration(udev);
1329         if (c < 0)
1330                 dev_warn(&udev->dev,
1331                                 "can't choose an initial configuration\n");
1332         else {
1333                 err = usb_set_configuration(udev, c);
1334                 if (err) {
1335                         dev_err(&udev->dev, "can't set config #%d, error %d\n",
1336                                         c, err);
1337                         usb_remove_sysfs_dev_files(udev);
1338                         device_del(&udev->dev);
1339                         goto fail;
1340                 }
1341         }
1342
1343         /* USB device state == configured ... usable */
1344
1345         /* add a /proc/bus/usb entry */
1346         usbdev_add(udev);
1347         usbfs_add_device(udev);
1348         return 0;
1349
1350 fail:
1351         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1352         return err;
1353 }
1354
1355
1356 static int hub_port_status(struct usb_hub *hub, int port1,
1357                                u16 *status, u16 *change)
1358 {
1359         int ret;
1360
1361         ret = get_port_status(hub->hdev, port1, &hub->status->port);
1362         if (ret < 0)
1363                 dev_err (hub->intfdev,
1364                         "%s failed (err = %d)\n", __FUNCTION__, ret);
1365         else {
1366                 *status = le16_to_cpu(hub->status->port.wPortStatus);
1367                 *change = le16_to_cpu(hub->status->port.wPortChange);
1368                 ret = 0;
1369         }
1370         return ret;
1371 }
1372
1373 #define PORT_RESET_TRIES        5
1374 #define SET_ADDRESS_TRIES       2
1375 #define GET_DESCRIPTOR_TRIES    2
1376 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1377 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1378
1379 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1380 #define HUB_SHORT_RESET_TIME    10
1381 #define HUB_LONG_RESET_TIME     200
1382 #define HUB_RESET_TIMEOUT       500
1383
1384 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1385                                 struct usb_device *udev, unsigned int delay)
1386 {
1387         int delay_time, ret;
1388         u16 portstatus;
1389         u16 portchange;
1390
1391         for (delay_time = 0;
1392                         delay_time < HUB_RESET_TIMEOUT;
1393                         delay_time += delay) {
1394                 /* wait to give the device a chance to reset */
1395                 msleep(delay);
1396
1397                 /* read and decode port status */
1398                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1399                 if (ret < 0)
1400                         return ret;
1401
1402                 /* Device went away? */
1403                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1404                         return -ENOTCONN;
1405
1406                 /* bomb out completely if something weird happened */
1407                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1408                         return -EINVAL;
1409
1410                 /* if we`ve finished resetting, then break out of the loop */
1411                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1412                     (portstatus & USB_PORT_STAT_ENABLE)) {
1413                         if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1414                                 udev->speed = USB_SPEED_HIGH;
1415                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1416                                 udev->speed = USB_SPEED_LOW;
1417                         else
1418                                 udev->speed = USB_SPEED_FULL;
1419                         return 0;
1420                 }
1421
1422                 /* switch to the long delay after two short delay failures */
1423                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1424                         delay = HUB_LONG_RESET_TIME;
1425
1426                 dev_dbg (hub->intfdev,
1427                         "port %d not reset yet, waiting %dms\n",
1428                         port1, delay);
1429         }
1430
1431         return -EBUSY;
1432 }
1433
1434 static int hub_port_reset(struct usb_hub *hub, int port1,
1435                                 struct usb_device *udev, unsigned int delay)
1436 {
1437         int i, status;
1438
1439         /* Reset the port */
1440         for (i = 0; i < PORT_RESET_TRIES; i++) {
1441                 status = set_port_feature(hub->hdev,
1442                                 port1, USB_PORT_FEAT_RESET);
1443                 if (status)
1444                         dev_err(hub->intfdev,
1445                                         "cannot reset port %d (err = %d)\n",
1446                                         port1, status);
1447                 else {
1448                         status = hub_port_wait_reset(hub, port1, udev, delay);
1449                         if (status)
1450                                 dev_dbg(hub->intfdev,
1451                                                 "port_wait_reset: err = %d\n",
1452                                                 status);
1453                 }
1454
1455                 /* return on disconnect or reset */
1456                 switch (status) {
1457                 case 0:
1458                         /* TRSTRCY = 10 ms */
1459                         msleep(10);
1460                         /* FALL THROUGH */
1461                 case -ENOTCONN:
1462                 case -ENODEV:
1463                         clear_port_feature(hub->hdev,
1464                                 port1, USB_PORT_FEAT_C_RESET);
1465                         /* FIXME need disconnect() for NOTATTACHED device */
1466                         usb_set_device_state(udev, status
1467                                         ? USB_STATE_NOTATTACHED
1468                                         : USB_STATE_DEFAULT);
1469                         return status;
1470                 }
1471
1472                 dev_dbg (hub->intfdev,
1473                         "port %d not enabled, trying reset again...\n",
1474                         port1);
1475                 delay = HUB_LONG_RESET_TIME;
1476         }
1477
1478         dev_err (hub->intfdev,
1479                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1480                 port1);
1481
1482         return status;
1483 }
1484
1485 /*
1486  * Disable a port and mark a logical connnect-change event, so that some
1487  * time later khubd will disconnect() any existing usb_device on the port
1488  * and will re-enumerate if there actually is a device attached.
1489  */
1490 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1491 {
1492         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1493         hub_port_disable(hub, port1, 1);
1494
1495         /* FIXME let caller ask to power down the port:
1496          *  - some devices won't enumerate without a VBUS power cycle
1497          *  - SRP saves power that way
1498          *  - usb_suspend_device(dev, PMSG_SUSPEND)
1499          * That's easy if this hub can switch power per-port, and
1500          * khubd reactivates the port later (timer, SRP, etc).
1501          * Powerdown must be optional, because of reset/DFU.
1502          */
1503
1504         set_bit(port1, hub->change_bits);
1505         kick_khubd(hub);
1506 }
1507
1508
1509 #ifdef  CONFIG_USB_SUSPEND
1510
1511 /*
1512  * Selective port suspend reduces power; most suspended devices draw
1513  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1514  * All devices below the suspended port are also suspended.
1515  *
1516  * Devices leave suspend state when the host wakes them up.  Some devices
1517  * also support "remote wakeup", where the device can activate the USB
1518  * tree above them to deliver data, such as a keypress or packet.  In
1519  * some cases, this wakes the USB host.
1520  */
1521 static int hub_port_suspend(struct usb_hub *hub, int port1,
1522                 struct usb_device *udev)
1523 {
1524         int     status;
1525
1526         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1527
1528         /* enable remote wakeup when appropriate; this lets the device
1529          * wake up the upstream hub (including maybe the root hub).
1530          *
1531          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1532          * we don't explicitly enable it here.
1533          */
1534         if (udev->actconfig
1535                         // && FIXME (remote wakeup enabled on this bus)
1536                         // ... currently assuming it's always appropriate
1537                         && (udev->actconfig->desc.bmAttributes
1538                                 & USB_CONFIG_ATT_WAKEUP) != 0) {
1539                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1540                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1541                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1542                                 NULL, 0,
1543                                 USB_CTRL_SET_TIMEOUT);
1544                 if (status)
1545                         dev_dbg(&udev->dev,
1546                                 "won't remote wakeup, status %d\n",
1547                                 status);
1548         }
1549
1550         /* see 7.1.7.6 */
1551         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1552         if (status) {
1553                 dev_dbg(hub->intfdev,
1554                         "can't suspend port %d, status %d\n",
1555                         port1, status);
1556                 /* paranoia:  "should not happen" */
1557                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1558                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1559                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1560                                 NULL, 0,
1561                                 USB_CTRL_SET_TIMEOUT);
1562         } else {
1563                 /* device has up to 10 msec to fully suspend */
1564                 dev_dbg(&udev->dev, "usb suspend\n");
1565                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1566                 msleep(10);
1567         }
1568         return status;
1569 }
1570
1571 /*
1572  * Devices on USB hub ports have only one "suspend" state, corresponding
1573  * to ACPI D2, "may cause the device to lose some context".
1574  * State transitions include:
1575  *
1576  *   - suspend, resume ... when the VBUS power link stays live
1577  *   - suspend, disconnect ... VBUS lost
1578  *
1579  * Once VBUS drop breaks the circuit, the port it's using has to go through
1580  * normal re-enumeration procedures, starting with enabling VBUS power.
1581  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1582  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1583  * timer, no SRP, no requests through sysfs.
1584  */
1585 static int __usb_suspend_device (struct usb_device *udev, int port1,
1586                                  pm_message_t state)
1587 {
1588         int     status;
1589
1590         /* caller owns the udev device lock */
1591         if (port1 < 0)
1592                 return port1;
1593
1594         if (udev->state == USB_STATE_SUSPENDED
1595                         || udev->state == USB_STATE_NOTATTACHED) {
1596                 return 0;
1597         }
1598
1599         /* suspend interface drivers; if this is a hub, it
1600          * suspends the child devices
1601          */
1602         if (udev->actconfig) {
1603                 int     i;
1604
1605                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1606                         struct usb_interface    *intf;
1607                         struct usb_driver       *driver;
1608
1609                         intf = udev->actconfig->interface[i];
1610                         if (state.event <= intf->dev.power.power_state.event)
1611                                 continue;
1612                         if (!intf->dev.driver)
1613                                 continue;
1614                         driver = to_usb_driver(intf->dev.driver);
1615
1616                         if (driver->suspend) {
1617                                 status = driver->suspend(intf, state);
1618                                 if (intf->dev.power.power_state.event != state.event
1619                                                 || status)
1620                                         dev_err(&intf->dev,
1621                                                 "suspend %d fail, code %d\n",
1622                                                 state.event, status);
1623                         }
1624
1625                         /* only drivers with suspend() can ever resume();
1626                          * and after power loss, even they won't.
1627                          * bus_rescan_devices() can rebind drivers later.
1628                          *
1629                          * FIXME the PM core self-deadlocks when unbinding
1630                          * drivers during suspend/resume ... everything grabs
1631                          * dpm_sem (not a spinlock, ugh).  we want to unbind,
1632                          * since we know every driver's probe/disconnect works
1633                          * even for drivers that can't suspend.
1634                          */
1635                         if (!driver->suspend || state.event > PM_EVENT_FREEZE) {
1636 #if 1
1637                                 dev_warn(&intf->dev, "resume is unsafe!\n");
1638 #else
1639                                 down_write(&usb_bus_type.rwsem);
1640                                 device_release_driver(&intf->dev);
1641                                 up_write(&usb_bus_type.rwsem);
1642 #endif
1643                         }
1644                 }
1645         }
1646
1647         /*
1648          * FIXME this needs port power off call paths too, to help force
1649          * USB into the "generic" PM model.  At least for devices on
1650          * ports that aren't using ganged switching (usually root hubs).
1651          *
1652          * NOTE: SRP-capable links should adopt more aggressive poweroff
1653          * policies (when HNP doesn't apply) once we have mechanisms to
1654          * turn power back on!  (Likely not before 2.7...)
1655          */
1656         if (state.event > PM_EVENT_FREEZE) {
1657                 dev_warn(&udev->dev, "no poweroff yet, suspending instead\n");
1658         }
1659
1660         /* "global suspend" of the HC-to-USB interface (root hub), or
1661          * "selective suspend" of just one hub-device link.
1662          */
1663         if (!udev->parent) {
1664                 struct usb_bus  *bus = udev->bus;
1665                 if (bus && bus->op->hub_suspend) {
1666                         status = bus->op->hub_suspend (bus);
1667                         if (status == 0) {
1668                                 dev_dbg(&udev->dev, "usb suspend\n");
1669                                 usb_set_device_state(udev,
1670                                                 USB_STATE_SUSPENDED);
1671                         }
1672                 } else
1673                         status = -EOPNOTSUPP;
1674         } else
1675                 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1676                                 udev);
1677
1678         if (status == 0)
1679                 udev->dev.power.power_state = state;
1680         return status;
1681 }
1682
1683 /**
1684  * usb_suspend_device - suspend a usb device
1685  * @udev: device that's no longer in active use
1686  * @state: PMSG_SUSPEND to suspend
1687  * Context: must be able to sleep; device not locked
1688  *
1689  * Suspends a USB device that isn't in active use, conserving power.
1690  * Devices may wake out of a suspend, if anything important happens,
1691  * using the remote wakeup mechanism.  They may also be taken out of
1692  * suspend by the host, using usb_resume_device().  It's also routine
1693  * to disconnect devices while they are suspended.
1694  *
1695  * Suspending OTG devices may trigger HNP, if that's been enabled
1696  * between a pair of dual-role devices.  That will change roles, such
1697  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1698  *
1699  * Returns 0 on success, else negative errno.
1700  */
1701 int usb_suspend_device(struct usb_device *udev, pm_message_t state)
1702 {
1703         int     port1, status;
1704
1705         port1 = locktree(udev);
1706         if (port1 < 0)
1707                 return port1;
1708
1709         status = __usb_suspend_device(udev, port1, state);
1710         usb_unlock_device(udev);
1711         return status;
1712 }
1713
1714 /*
1715  * hardware resume signaling is finished, either because of selective
1716  * resume (by host) or remote wakeup (by device) ... now see what changed
1717  * in the tree that's rooted at this device.
1718  */
1719 static int finish_port_resume(struct usb_device *udev)
1720 {
1721         int     status;
1722         u16     devstatus;
1723
1724         /* caller owns the udev device lock */
1725         dev_dbg(&udev->dev, "usb resume\n");
1726
1727         /* usb ch9 identifies four variants of SUSPENDED, based on what
1728          * state the device resumes to.  Linux currently won't see the
1729          * first two on the host side; they'd be inside hub_port_init()
1730          * during many timeouts, but khubd can't suspend until later.
1731          */
1732         usb_set_device_state(udev, udev->actconfig
1733                         ? USB_STATE_CONFIGURED
1734                         : USB_STATE_ADDRESS);
1735         udev->dev.power.power_state = PMSG_ON;
1736
1737         /* 10.5.4.5 says be sure devices in the tree are still there.
1738          * For now let's assume the device didn't go crazy on resume,
1739          * and device drivers will know about any resume quirks.
1740          */
1741         status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1742         if (status < 0)
1743                 dev_dbg(&udev->dev,
1744                         "gone after usb resume? status %d\n",
1745                         status);
1746         else if (udev->actconfig) {
1747                 unsigned        i;
1748
1749                 le16_to_cpus(&devstatus);
1750                 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
1751                         status = usb_control_msg(udev,
1752                                         usb_sndctrlpipe(udev, 0),
1753                                         USB_REQ_CLEAR_FEATURE,
1754                                                 USB_RECIP_DEVICE,
1755                                         USB_DEVICE_REMOTE_WAKEUP, 0,
1756                                         NULL, 0,
1757                                         USB_CTRL_SET_TIMEOUT);
1758                         if (status) {
1759                                 dev_dbg(&udev->dev, "disable remote "
1760                                         "wakeup, status %d\n", status);
1761                                 status = 0;
1762                         }
1763                 }
1764
1765                 /* resume interface drivers; if this is a hub, it
1766                  * resumes the child devices
1767                  */
1768                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1769                         struct usb_interface    *intf;
1770                         struct usb_driver       *driver;
1771
1772                         intf = udev->actconfig->interface[i];
1773                         if (intf->dev.power.power_state.event == PM_EVENT_ON)
1774                                 continue;
1775                         if (!intf->dev.driver) {
1776                                 /* FIXME maybe force to alt 0 */
1777                                 continue;
1778                         }
1779                         driver = to_usb_driver(intf->dev.driver);
1780
1781                         /* bus_rescan_devices() may rebind drivers */
1782                         if (!driver->resume)
1783                                 continue;
1784
1785                         /* can we do better than just logging errors? */
1786                         status = driver->resume(intf);
1787                         if (intf->dev.power.power_state.event != PM_EVENT_ON
1788                                         || status)
1789                                 dev_dbg(&intf->dev,
1790                                         "resume fail, state %d code %d\n",
1791                                         intf->dev.power.power_state.event, status);
1792                 }
1793                 status = 0;
1794
1795         } else if (udev->devnum <= 0) {
1796                 dev_dbg(&udev->dev, "bogus resume!\n");
1797                 status = -EINVAL;
1798         }
1799         return status;
1800 }
1801
1802 static int
1803 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1804 {
1805         int     status;
1806
1807         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1808
1809         /* see 7.1.7.7; affects power usage, but not budgeting */
1810         status = clear_port_feature(hub->hdev,
1811                         port1, USB_PORT_FEAT_SUSPEND);
1812         if (status) {
1813                 dev_dbg(hub->intfdev,
1814                         "can't resume port %d, status %d\n",
1815                         port1, status);
1816         } else {
1817                 u16             devstatus;
1818                 u16             portchange;
1819
1820                 /* drive resume for at least 20 msec */
1821                 if (udev)
1822                         dev_dbg(&udev->dev, "RESUME\n");
1823                 msleep(25);
1824
1825 #define LIVE_FLAGS      ( USB_PORT_STAT_POWER \
1826                         | USB_PORT_STAT_ENABLE \
1827                         | USB_PORT_STAT_CONNECTION)
1828
1829                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1830                  * stop resume signaling.  Then finish the resume
1831                  * sequence.
1832                  */
1833                 devstatus = portchange = 0;
1834                 status = hub_port_status(hub, port1,
1835                                 &devstatus, &portchange);
1836                 if (status < 0
1837                                 || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
1838                                 || (devstatus & USB_PORT_STAT_SUSPEND) != 0
1839                                 ) {
1840                         dev_dbg(hub->intfdev,
1841                                 "port %d status %04x.%04x after resume, %d\n",
1842                                 port1, portchange, devstatus, status);
1843                 } else {
1844                         /* TRSMRCY = 10 msec */
1845                         msleep(10);
1846                         if (udev)
1847                                 status = finish_port_resume(udev);
1848                 }
1849         }
1850         if (status < 0)
1851                 hub_port_logical_disconnect(hub, port1);
1852
1853         return status;
1854 }
1855
1856 static int hub_resume (struct usb_interface *intf);
1857
1858 /**
1859  * usb_resume_device - re-activate a suspended usb device
1860  * @udev: device to re-activate
1861  * Context: must be able to sleep; device not locked
1862  *
1863  * This will re-activate the suspended device, increasing power usage
1864  * while letting drivers communicate again with its endpoints.
1865  * USB resume explicitly guarantees that the power session between
1866  * the host and the device is the same as it was when the device
1867  * suspended.
1868  *
1869  * Returns 0 on success, else negative errno.
1870  */
1871 int usb_resume_device(struct usb_device *udev)
1872 {
1873         int     port1, status;
1874
1875         port1 = locktree(udev);
1876         if (port1 < 0)
1877                 return port1;
1878
1879         /* "global resume" of the HC-to-USB interface (root hub), or
1880          * selective resume of one hub-to-device port
1881          */
1882         if (!udev->parent) {
1883                 struct usb_bus  *bus = udev->bus;
1884                 if (bus && bus->op->hub_resume) {
1885                         status = bus->op->hub_resume (bus);
1886                 } else
1887                         status = -EOPNOTSUPP;
1888                 if (status == 0) {
1889                         dev_dbg(&udev->dev, "usb resume\n");
1890                         /* TRSMRCY = 10 msec */
1891                         msleep(10);
1892                         usb_set_device_state (udev, USB_STATE_CONFIGURED);
1893                         udev->dev.power.power_state = PMSG_ON;
1894                         status = hub_resume (udev
1895                                         ->actconfig->interface[0]);
1896                 }
1897         } else if (udev->state == USB_STATE_SUSPENDED) {
1898                 // NOTE this fails if parent is also suspended...
1899                 status = hub_port_resume(hdev_to_hub(udev->parent),
1900                                 port1, udev);
1901         } else {
1902                 status = 0;
1903         }
1904         if (status < 0) {
1905                 dev_dbg(&udev->dev, "can't resume, status %d\n",
1906                         status);
1907         }
1908
1909         usb_unlock_device(udev);
1910
1911         /* rebind drivers that had no suspend() */
1912         if (status == 0) {
1913                 usb_lock_all_devices();
1914                 bus_rescan_devices(&usb_bus_type);
1915                 usb_unlock_all_devices();
1916         }
1917         return status;
1918 }
1919
1920 static int remote_wakeup(struct usb_device *udev)
1921 {
1922         int     status = 0;
1923
1924         /* don't repeat RESUME sequence if this device
1925          * was already woken up by some other task
1926          */
1927         down(&udev->serialize);
1928         if (udev->state == USB_STATE_SUSPENDED) {
1929                 dev_dbg(&udev->dev, "RESUME (wakeup)\n");
1930                 /* TRSMRCY = 10 msec */
1931                 msleep(10);
1932                 status = finish_port_resume(udev);
1933         }
1934         up(&udev->serialize);
1935         return status;
1936 }
1937
1938 static int hub_suspend(struct usb_interface *intf, pm_message_t state)
1939 {
1940         struct usb_hub          *hub = usb_get_intfdata (intf);
1941         struct usb_device       *hdev = hub->hdev;
1942         unsigned                port1;
1943         int                     status;
1944
1945         /* stop khubd and related activity */
1946         hub_quiesce(hub);
1947
1948         /* then suspend every port */
1949         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1950                 struct usb_device       *udev;
1951
1952                 udev = hdev->children [port1-1];
1953                 if (!udev)
1954                         continue;
1955                 down(&udev->serialize);
1956                 status = __usb_suspend_device(udev, port1, state);
1957                 up(&udev->serialize);
1958                 if (status < 0)
1959                         dev_dbg(&intf->dev, "suspend port %d --> %d\n",
1960                                 port1, status);
1961         }
1962
1963         intf->dev.power.power_state = state;
1964         return 0;
1965 }
1966
1967 static int hub_resume(struct usb_interface *intf)
1968 {
1969         struct usb_device       *hdev = interface_to_usbdev(intf);
1970         struct usb_hub          *hub = usb_get_intfdata (intf);
1971         unsigned                port1;
1972         int                     status;
1973
1974         if (intf->dev.power.power_state.event == PM_EVENT_ON)
1975                 return 0;
1976
1977         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1978                 struct usb_device       *udev;
1979                 u16                     portstat, portchange;
1980
1981                 udev = hdev->children [port1-1];
1982                 status = hub_port_status(hub, port1, &portstat, &portchange);
1983                 if (status == 0) {
1984                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
1985                                 clear_port_feature(hdev, port1,
1986                                         USB_PORT_FEAT_C_SUSPEND);
1987                                 portchange &= ~USB_PORT_STAT_C_SUSPEND;
1988                         }
1989
1990                         /* let khubd handle disconnects etc */
1991                         if (portchange)
1992                                 continue;
1993                 }
1994
1995                 if (!udev || status < 0)
1996                         continue;
1997                 down (&udev->serialize);
1998                 if (portstat & USB_PORT_STAT_SUSPEND)
1999                         status = hub_port_resume(hub, port1, udev);
2000                 else {
2001                         status = finish_port_resume(udev);
2002                         if (status < 0) {
2003                                 dev_dbg(&intf->dev, "resume port %d --> %d\n",
2004                                         port1, status);
2005                                 hub_port_logical_disconnect(hub, port1);
2006                         }
2007                 }
2008                 up(&udev->serialize);
2009         }
2010         intf->dev.power.power_state = PMSG_ON;
2011
2012         hub->resume_root_hub = 0;
2013         hub_activate(hub);
2014         return 0;
2015 }
2016
2017 void usb_resume_root_hub(struct usb_device *hdev)
2018 {
2019         struct usb_hub *hub = hdev_to_hub(hdev);
2020
2021         hub->resume_root_hub = 1;
2022         kick_khubd(hub);
2023 }
2024
2025 #else   /* !CONFIG_USB_SUSPEND */
2026
2027 int usb_suspend_device(struct usb_device *udev, pm_message_t state)
2028 {
2029         return 0;
2030 }
2031
2032 int usb_resume_device(struct usb_device *udev)
2033 {
2034         return 0;
2035 }
2036
2037 #define hub_suspend             NULL
2038 #define hub_resume              NULL
2039 #define remote_wakeup(x)        0
2040
2041 #endif  /* CONFIG_USB_SUSPEND */
2042
2043 EXPORT_SYMBOL(usb_suspend_device);
2044 EXPORT_SYMBOL(usb_resume_device);
2045
2046
2047
2048 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2049  *
2050  * Between connect detection and reset signaling there must be a delay
2051  * of 100ms at least for debounce and power-settling.  The corresponding
2052  * timer shall restart whenever the downstream port detects a disconnect.
2053  *
2054  * Apparently there are some bluetooth and irda-dongles and a number of
2055  * low-speed devices for which this debounce period may last over a second.
2056  * Not covered by the spec - but easy to deal with.
2057  *
2058  * This implementation uses a 1500ms total debounce timeout; if the
2059  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
2060  * every 25ms for transient disconnects.  When the port status has been
2061  * unchanged for 100ms it returns the port status.
2062  */
2063
2064 #define HUB_DEBOUNCE_TIMEOUT    1500
2065 #define HUB_DEBOUNCE_STEP         25
2066 #define HUB_DEBOUNCE_STABLE      100
2067
2068 static int hub_port_debounce(struct usb_hub *hub, int port1)
2069 {
2070         int ret;
2071         int total_time, stable_time = 0;
2072         u16 portchange, portstatus;
2073         unsigned connection = 0xffff;
2074
2075         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2076                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2077                 if (ret < 0)
2078                         return ret;
2079
2080                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2081                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2082                         stable_time += HUB_DEBOUNCE_STEP;
2083                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2084                                 break;
2085                 } else {
2086                         stable_time = 0;
2087                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2088                 }
2089
2090                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2091                         clear_port_feature(hub->hdev, port1,
2092                                         USB_PORT_FEAT_C_CONNECTION);
2093                 }
2094
2095                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2096                         break;
2097                 msleep(HUB_DEBOUNCE_STEP);
2098         }
2099
2100         dev_dbg (hub->intfdev,
2101                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2102                 port1, total_time, stable_time, portstatus);
2103
2104         if (stable_time < HUB_DEBOUNCE_STABLE)
2105                 return -ETIMEDOUT;
2106         return portstatus;
2107 }
2108
2109 static void ep0_reinit(struct usb_device *udev)
2110 {
2111         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2112         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2113         udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2114 }
2115
2116 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2117 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2118
2119 static int hub_set_address(struct usb_device *udev)
2120 {
2121         int retval;
2122
2123         if (udev->devnum == 0)
2124                 return -EINVAL;
2125         if (udev->state == USB_STATE_ADDRESS)
2126                 return 0;
2127         if (udev->state != USB_STATE_DEFAULT)
2128                 return -EINVAL;
2129         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2130                 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2131                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2132         if (retval == 0) {
2133                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2134                 ep0_reinit(udev);
2135         }
2136         return retval;
2137 }
2138
2139 /* Reset device, (re)assign address, get device descriptor.
2140  * Device connection must be stable, no more debouncing needed.
2141  * Returns device in USB_STATE_ADDRESS, except on error.
2142  *
2143  * If this is called for an already-existing device (as part of
2144  * usb_reset_device), the caller must own the device lock.  For a
2145  * newly detected device that is not accessible through any global
2146  * pointers, it's not necessary to lock the device.
2147  */
2148 static int
2149 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2150                 int retry_counter)
2151 {
2152         static DECLARE_MUTEX(usb_address0_sem);
2153
2154         struct usb_device       *hdev = hub->hdev;
2155         int                     i, j, retval;
2156         unsigned                delay = HUB_SHORT_RESET_TIME;
2157         enum usb_device_speed   oldspeed = udev->speed;
2158
2159         /* root hub ports have a slightly longer reset period
2160          * (from USB 2.0 spec, section 7.1.7.5)
2161          */
2162         if (!hdev->parent) {
2163                 delay = HUB_ROOT_RESET_TIME;
2164                 if (port1 == hdev->bus->otg_port)
2165                         hdev->bus->b_hnp_enable = 0;
2166         }
2167
2168         /* Some low speed devices have problems with the quick delay, so */
2169         /*  be a bit pessimistic with those devices. RHbug #23670 */
2170         if (oldspeed == USB_SPEED_LOW)
2171                 delay = HUB_LONG_RESET_TIME;
2172
2173         down(&usb_address0_sem);
2174
2175         /* Reset the device; full speed may morph to high speed */
2176         retval = hub_port_reset(hub, port1, udev, delay);
2177         if (retval < 0)         /* error or disconnect */
2178                 goto fail;
2179                                 /* success, speed is known */
2180         retval = -ENODEV;
2181
2182         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2183                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2184                 goto fail;
2185         }
2186         oldspeed = udev->speed;
2187
2188         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2189          * it's fixed size except for full speed devices.
2190          */
2191         switch (udev->speed) {
2192         case USB_SPEED_HIGH:            /* fixed at 64 */
2193                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2194                 break;
2195         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2196                 /* to determine the ep0 maxpacket size, try to read
2197                  * the device descriptor to get bMaxPacketSize0 and
2198                  * then correct our initial guess.
2199                  */
2200                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2201                 break;
2202         case USB_SPEED_LOW:             /* fixed at 8 */
2203                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2204                 break;
2205         default:
2206                 goto fail;
2207         }
2208
2209         dev_info (&udev->dev,
2210                         "%s %s speed USB device using %s and address %d\n",
2211                         (udev->config) ? "reset" : "new",
2212                         ({ char *speed; switch (udev->speed) {
2213                         case USB_SPEED_LOW:     speed = "low";  break;
2214                         case USB_SPEED_FULL:    speed = "full"; break;
2215                         case USB_SPEED_HIGH:    speed = "high"; break;
2216                         default:                speed = "?";    break;
2217                         }; speed;}),
2218                         udev->bus->controller->driver->name,
2219                         udev->devnum);
2220
2221         /* Set up TT records, if needed  */
2222         if (hdev->tt) {
2223                 udev->tt = hdev->tt;
2224                 udev->ttport = hdev->ttport;
2225         } else if (udev->speed != USB_SPEED_HIGH
2226                         && hdev->speed == USB_SPEED_HIGH) {
2227                 udev->tt = &hub->tt;
2228                 udev->ttport = port1;
2229         }
2230
2231         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2232          * Because device hardware and firmware is sometimes buggy in
2233          * this area, and this is how Linux has done it for ages.
2234          * Change it cautiously.
2235          *
2236          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2237          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2238          * so it may help with some non-standards-compliant devices.
2239          * Otherwise we start with SET_ADDRESS and then try to read the
2240          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2241          * value.
2242          */
2243         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2244                 if (USE_NEW_SCHEME(retry_counter)) {
2245                         struct usb_device_descriptor *buf;
2246                         int r = 0;
2247
2248 #define GET_DESCRIPTOR_BUFSIZE  64
2249                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2250                         if (!buf) {
2251                                 retval = -ENOMEM;
2252                                 continue;
2253                         }
2254
2255                         /* Use a short timeout the first time through,
2256                          * so that recalcitrant full-speed devices with
2257                          * 8- or 16-byte ep0-maxpackets won't slow things
2258                          * down tremendously by NAKing the unexpectedly
2259                          * early status stage.  Also, retry on all errors;
2260                          * some devices are flakey.
2261                          */
2262                         for (j = 0; j < 3; ++j) {
2263                                 buf->bMaxPacketSize0 = 0;
2264                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2265                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2266                                         USB_DT_DEVICE << 8, 0,
2267                                         buf, GET_DESCRIPTOR_BUFSIZE,
2268                                         (i ? USB_CTRL_GET_TIMEOUT : 1000));
2269                                 switch (buf->bMaxPacketSize0) {
2270                                 case 8: case 16: case 32: case 64:
2271                                         if (buf->bDescriptorType ==
2272                                                         USB_DT_DEVICE) {
2273                                                 r = 0;
2274                                                 break;
2275                                         }
2276                                         /* FALL THROUGH */
2277                                 default:
2278                                         if (r == 0)
2279                                                 r = -EPROTO;
2280                                         break;
2281                                 }
2282                                 if (r == 0)
2283                                         break;
2284                         }
2285                         udev->descriptor.bMaxPacketSize0 =
2286                                         buf->bMaxPacketSize0;
2287                         kfree(buf);
2288
2289                         retval = hub_port_reset(hub, port1, udev, delay);
2290                         if (retval < 0)         /* error or disconnect */
2291                                 goto fail;
2292                         if (oldspeed != udev->speed) {
2293                                 dev_dbg(&udev->dev,
2294                                         "device reset changed speed!\n");
2295                                 retval = -ENODEV;
2296                                 goto fail;
2297                         }
2298                         if (r) {
2299                                 dev_err(&udev->dev, "device descriptor "
2300                                                 "read/%s, error %d\n",
2301                                                 "64", r);
2302                                 retval = -EMSGSIZE;
2303                                 continue;
2304                         }
2305 #undef GET_DESCRIPTOR_BUFSIZE
2306                 }
2307
2308                 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2309                         retval = hub_set_address(udev);
2310                         if (retval >= 0)
2311                                 break;
2312                         msleep(200);
2313                 }
2314                 if (retval < 0) {
2315                         dev_err(&udev->dev,
2316                                 "device not accepting address %d, error %d\n",
2317                                 udev->devnum, retval);
2318                         goto fail;
2319                 }
2320
2321                 /* cope with hardware quirkiness:
2322                  *  - let SET_ADDRESS settle, some device hardware wants it
2323                  *  - read ep0 maxpacket even for high and low speed,
2324                  */
2325                 msleep(10);
2326                 if (USE_NEW_SCHEME(retry_counter))
2327                         break;
2328
2329                 retval = usb_get_device_descriptor(udev, 8);
2330                 if (retval < 8) {
2331                         dev_err(&udev->dev, "device descriptor "
2332                                         "read/%s, error %d\n",
2333                                         "8", retval);
2334                         if (retval >= 0)
2335                                 retval = -EMSGSIZE;
2336                 } else {
2337                         retval = 0;
2338                         break;
2339                 }
2340         }
2341         if (retval)
2342                 goto fail;
2343
2344         i = udev->descriptor.bMaxPacketSize0;
2345         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2346                 if (udev->speed != USB_SPEED_FULL ||
2347                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2348                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2349                         retval = -EMSGSIZE;
2350                         goto fail;
2351                 }
2352                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2353                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2354                 ep0_reinit(udev);
2355         }
2356
2357         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2358         if (retval < (signed)sizeof(udev->descriptor)) {
2359                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2360                         "all", retval);
2361                 if (retval >= 0)
2362                         retval = -ENOMSG;
2363                 goto fail;
2364         }
2365
2366         retval = 0;
2367
2368 fail:
2369         if (retval)
2370                 hub_port_disable(hub, port1, 0);
2371         up(&usb_address0_sem);
2372         return retval;
2373 }
2374
2375 static void
2376 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2377 {
2378         struct usb_qualifier_descriptor *qual;
2379         int                             status;
2380
2381         qual = kmalloc (sizeof *qual, SLAB_KERNEL);
2382         if (qual == NULL)
2383                 return;
2384
2385         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2386                         qual, sizeof *qual);
2387         if (status == sizeof *qual) {
2388                 dev_info(&udev->dev, "not running at top speed; "
2389                         "connect to a high speed hub\n");
2390                 /* hub LEDs are probably harder to miss than syslog */
2391                 if (hub->has_indicators) {
2392                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2393                         schedule_work (&hub->leds);
2394                 }
2395         }
2396         kfree(qual);
2397 }
2398
2399 static unsigned
2400 hub_power_remaining (struct usb_hub *hub)
2401 {
2402         struct usb_device *hdev = hub->hdev;
2403         int remaining;
2404         unsigned i;
2405
2406         remaining = hub->power_budget;
2407         if (!remaining)         /* self-powered */
2408                 return 0;
2409
2410         for (i = 0; i < hdev->maxchild; i++) {
2411                 struct usb_device       *udev = hdev->children[i];
2412                 int                     delta, ceiling;
2413
2414                 if (!udev)
2415                         continue;
2416
2417                 /* 100mA per-port ceiling, or 8mA for OTG ports */
2418                 if (i != (udev->bus->otg_port - 1) || hdev->parent)
2419                         ceiling = 50;
2420                 else
2421                         ceiling = 4;
2422
2423                 if (udev->actconfig)
2424                         delta = udev->actconfig->desc.bMaxPower;
2425                 else
2426                         delta = ceiling;
2427                 // dev_dbg(&udev->dev, "budgeted %dmA\n", 2 * delta);
2428                 if (delta > ceiling)
2429                         dev_warn(&udev->dev, "%dmA over %dmA budget!\n",
2430                                 2 * (delta - ceiling), 2 * ceiling);
2431                 remaining -= delta;
2432         }
2433         if (remaining < 0) {
2434                 dev_warn(hub->intfdev,
2435                         "%dmA over power budget!\n",
2436                         -2 * remaining);
2437                 remaining = 0;
2438         }
2439         return remaining;
2440 }
2441
2442 /* Handle physical or logical connection change events.
2443  * This routine is called when:
2444  *      a port connection-change occurs;
2445  *      a port enable-change occurs (often caused by EMI);
2446  *      usb_reset_device() encounters changed descriptors (as from
2447  *              a firmware download)
2448  * caller already locked the hub
2449  */
2450 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2451                                         u16 portstatus, u16 portchange)
2452 {
2453         struct usb_device *hdev = hub->hdev;
2454         struct device *hub_dev = hub->intfdev;
2455         int status, i;
2456
2457         dev_dbg (hub_dev,
2458                 "port %d, status %04x, change %04x, %s\n",
2459                 port1, portstatus, portchange, portspeed (portstatus));
2460
2461         if (hub->has_indicators) {
2462                 set_port_led(hub, port1, HUB_LED_AUTO);
2463                 hub->indicator[port1-1] = INDICATOR_AUTO;
2464         }
2465
2466         /* Disconnect any existing devices under this port */
2467         if (hdev->children[port1-1])
2468                 usb_disconnect(&hdev->children[port1-1]);
2469         clear_bit(port1, hub->change_bits);
2470
2471 #ifdef  CONFIG_USB_OTG
2472         /* during HNP, don't repeat the debounce */
2473         if (hdev->bus->is_b_host)
2474                 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2475 #endif
2476
2477         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2478                 status = hub_port_debounce(hub, port1);
2479                 if (status < 0) {
2480                         dev_err (hub_dev,
2481                                 "connect-debounce failed, port %d disabled\n",
2482                                 port1);
2483                         goto done;
2484                 }
2485                 portstatus = status;
2486         }
2487
2488         /* Return now if nothing is connected */
2489         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2490
2491                 /* maybe switch power back on (e.g. root hub was reset) */
2492                 if ((hub->descriptor->wHubCharacteristics
2493                                         & HUB_CHAR_LPSM) < 2
2494                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2495                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2496
2497                 if (portstatus & USB_PORT_STAT_ENABLE)
2498                         goto done;
2499                 return;
2500         }
2501
2502 #ifdef  CONFIG_USB_SUSPEND
2503         /* If something is connected, but the port is suspended, wake it up. */
2504         if (portstatus & USB_PORT_STAT_SUSPEND) {
2505                 status = hub_port_resume(hub, port1, NULL);
2506                 if (status < 0) {
2507                         dev_dbg(hub_dev,
2508                                 "can't clear suspend on port %d; %d\n",
2509                                 port1, status);
2510                         goto done;
2511                 }
2512         }
2513 #endif
2514
2515         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2516                 struct usb_device *udev;
2517
2518                 /* reallocate for each attempt, since references
2519                  * to the previous one can escape in various ways
2520                  */
2521                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2522                 if (!udev) {
2523                         dev_err (hub_dev,
2524                                 "couldn't allocate port %d usb_device\n",
2525                                 port1);
2526                         goto done;
2527                 }
2528
2529                 usb_set_device_state(udev, USB_STATE_POWERED);
2530                 udev->speed = USB_SPEED_UNKNOWN;
2531
2532                 /* set the address */
2533                 choose_address(udev);
2534                 if (udev->devnum <= 0) {
2535                         status = -ENOTCONN;     /* Don't retry */
2536                         goto loop;
2537                 }
2538
2539                 /* reset and get descriptor */
2540                 status = hub_port_init(hub, udev, port1, i);
2541                 if (status < 0)
2542                         goto loop;
2543
2544                 /* consecutive bus-powered hubs aren't reliable; they can
2545                  * violate the voltage drop budget.  if the new child has
2546                  * a "powered" LED, users should notice we didn't enable it
2547                  * (without reading syslog), even without per-port LEDs
2548                  * on the parent.
2549                  */
2550                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2551                                 && hub->power_budget) {
2552                         u16     devstat;
2553
2554                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2555                                         &devstat);
2556                         if (status < 0) {
2557                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2558                                 goto loop_disable;
2559                         }
2560                         cpu_to_le16s(&devstat);
2561                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2562                                 dev_err(&udev->dev,
2563                                         "can't connect bus-powered hub "
2564                                         "to this port\n");
2565                                 if (hub->has_indicators) {
2566                                         hub->indicator[port1-1] =
2567                                                 INDICATOR_AMBER_BLINK;
2568                                         schedule_work (&hub->leds);
2569                                 }
2570                                 status = -ENOTCONN;     /* Don't retry */
2571                                 goto loop_disable;
2572                         }
2573                 }
2574
2575                 /* check for devices running slower than they could */
2576                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2577                                 && udev->speed == USB_SPEED_FULL
2578                                 && highspeed_hubs != 0)
2579                         check_highspeed (hub, udev, port1);
2580
2581                 /* Store the parent's children[] pointer.  At this point
2582                  * udev becomes globally accessible, although presumably
2583                  * no one will look at it until hdev is unlocked.
2584                  */
2585                 down (&udev->serialize);
2586                 status = 0;
2587
2588                 /* We mustn't add new devices if the parent hub has
2589                  * been disconnected; we would race with the
2590                  * recursively_mark_NOTATTACHED() routine.
2591                  */
2592                 spin_lock_irq(&device_state_lock);
2593                 if (hdev->state == USB_STATE_NOTATTACHED)
2594                         status = -ENOTCONN;
2595                 else
2596                         hdev->children[port1-1] = udev;
2597                 spin_unlock_irq(&device_state_lock);
2598
2599                 /* Run it through the hoops (find a driver, etc) */
2600                 if (!status) {
2601                         status = usb_new_device(udev);
2602                         if (status) {
2603                                 spin_lock_irq(&device_state_lock);
2604                                 hdev->children[port1-1] = NULL;
2605                                 spin_unlock_irq(&device_state_lock);
2606                         }
2607                 }
2608
2609                 up (&udev->serialize);
2610                 if (status)
2611                         goto loop_disable;
2612
2613                 status = hub_power_remaining(hub);
2614                 if (status)
2615                         dev_dbg(hub_dev,
2616                                 "%dmA power budget left\n",
2617                                 2 * status);
2618
2619                 return;
2620
2621 loop_disable:
2622                 hub_port_disable(hub, port1, 1);
2623 loop:
2624                 ep0_reinit(udev);
2625                 release_address(udev);
2626                 usb_put_dev(udev);
2627                 if (status == -ENOTCONN)
2628                         break;
2629         }
2630
2631 done:
2632         hub_port_disable(hub, port1, 1);
2633 }
2634
2635 static void hub_events(void)
2636 {
2637         struct list_head *tmp;
2638         struct usb_device *hdev;
2639         struct usb_interface *intf;
2640         struct usb_hub *hub;
2641         struct device *hub_dev;
2642         u16 hubstatus;
2643         u16 hubchange;
2644         u16 portstatus;
2645         u16 portchange;
2646         int i, ret;
2647         int connect_change;
2648
2649         /*
2650          *  We restart the list every time to avoid a deadlock with
2651          * deleting hubs downstream from this one. This should be
2652          * safe since we delete the hub from the event list.
2653          * Not the most efficient, but avoids deadlocks.
2654          */
2655         while (1) {
2656
2657                 /* Grab the first entry at the beginning of the list */
2658                 spin_lock_irq(&hub_event_lock);
2659                 if (list_empty(&hub_event_list)) {
2660                         spin_unlock_irq(&hub_event_lock);
2661                         break;
2662                 }
2663
2664                 tmp = hub_event_list.next;
2665                 list_del_init(tmp);
2666
2667                 hub = list_entry(tmp, struct usb_hub, event_list);
2668                 hdev = hub->hdev;
2669                 intf = to_usb_interface(hub->intfdev);
2670                 hub_dev = &intf->dev;
2671
2672                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
2673                                 hdev->state, hub->descriptor
2674                                         ? hub->descriptor->bNbrPorts
2675                                         : 0,
2676                                 /* NOTE: expects max 15 ports... */
2677                                 (u16) hub->change_bits[0],
2678                                 (u16) hub->event_bits[0]);
2679
2680                 usb_get_intf(intf);
2681                 i = hub->resume_root_hub;
2682                 spin_unlock_irq(&hub_event_lock);
2683
2684                 /* Is this is a root hub wanting to be resumed? */
2685                 if (i)
2686                         usb_resume_device(hdev);
2687
2688                 /* Lock the device, then check to see if we were
2689                  * disconnected while waiting for the lock to succeed. */
2690                 if (locktree(hdev) < 0) {
2691                         usb_put_intf(intf);
2692                         continue;
2693                 }
2694                 if (hub != usb_get_intfdata(intf))
2695                         goto loop;
2696
2697                 /* If the hub has died, clean up after it */
2698                 if (hdev->state == USB_STATE_NOTATTACHED) {
2699                         hub_pre_reset(hub);
2700                         goto loop;
2701                 }
2702
2703                 /* If this is an inactive or suspended hub, do nothing */
2704                 if (hub->quiescing)
2705                         goto loop;
2706
2707                 if (hub->error) {
2708                         dev_dbg (hub_dev, "resetting for error %d\n",
2709                                 hub->error);
2710
2711                         ret = usb_reset_device(hdev);
2712                         if (ret) {
2713                                 dev_dbg (hub_dev,
2714                                         "error resetting hub: %d\n", ret);
2715                                 goto loop;
2716                         }
2717
2718                         hub->nerrors = 0;
2719                         hub->error = 0;
2720                 }
2721
2722                 /* deal with port status changes */
2723                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2724                         if (test_bit(i, hub->busy_bits))
2725                                 continue;
2726                         connect_change = test_bit(i, hub->change_bits);
2727                         if (!test_and_clear_bit(i, hub->event_bits) &&
2728                                         !connect_change && !hub->activating)
2729                                 continue;
2730
2731                         ret = hub_port_status(hub, i,
2732                                         &portstatus, &portchange);
2733                         if (ret < 0)
2734                                 continue;
2735
2736                         if (hub->activating && !hdev->children[i-1] &&
2737                                         (portstatus &
2738                                                 USB_PORT_STAT_CONNECTION))
2739                                 connect_change = 1;
2740
2741                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2742                                 clear_port_feature(hdev, i,
2743                                         USB_PORT_FEAT_C_CONNECTION);
2744                                 connect_change = 1;
2745                         }
2746
2747                         if (portchange & USB_PORT_STAT_C_ENABLE) {
2748                                 if (!connect_change)
2749                                         dev_dbg (hub_dev,
2750                                                 "port %d enable change, "
2751                                                 "status %08x\n",
2752                                                 i, portstatus);
2753                                 clear_port_feature(hdev, i,
2754                                         USB_PORT_FEAT_C_ENABLE);
2755
2756                                 /*
2757                                  * EM interference sometimes causes badly
2758                                  * shielded USB devices to be shutdown by
2759                                  * the hub, this hack enables them again.
2760                                  * Works at least with mouse driver.
2761                                  */
2762                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
2763                                     && !connect_change
2764                                     && hdev->children[i-1]) {
2765                                         dev_err (hub_dev,
2766                                             "port %i "
2767                                             "disabled by hub (EMI?), "
2768                                             "re-enabling...\n",
2769                                                 i);
2770                                         connect_change = 1;
2771                                 }
2772                         }
2773
2774                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2775                                 clear_port_feature(hdev, i,
2776                                         USB_PORT_FEAT_C_SUSPEND);
2777                                 if (hdev->children[i-1]) {
2778                                         ret = remote_wakeup(hdev->
2779                                                         children[i-1]);
2780                                         if (ret < 0)
2781                                                 connect_change = 1;
2782                                 } else {
2783                                         ret = -ENODEV;
2784                                         hub_port_disable(hub, i, 1);
2785                                 }
2786                                 dev_dbg (hub_dev,
2787                                         "resume on port %d, status %d\n",
2788                                         i, ret);
2789                         }
2790
2791                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2792                                 dev_err (hub_dev,
2793                                         "over-current change on port %d\n",
2794                                         i);
2795                                 clear_port_feature(hdev, i,
2796                                         USB_PORT_FEAT_C_OVER_CURRENT);
2797                                 hub_power_on(hub);
2798                         }
2799
2800                         if (portchange & USB_PORT_STAT_C_RESET) {
2801                                 dev_dbg (hub_dev,
2802                                         "reset change on port %d\n",
2803                                         i);
2804                                 clear_port_feature(hdev, i,
2805                                         USB_PORT_FEAT_C_RESET);
2806                         }
2807
2808                         if (connect_change)
2809                                 hub_port_connect_change(hub, i,
2810                                                 portstatus, portchange);
2811                 } /* end for i */
2812
2813                 /* deal with hub status changes */
2814                 if (test_and_clear_bit(0, hub->event_bits) == 0)
2815                         ;       /* do nothing */
2816                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2817                         dev_err (hub_dev, "get_hub_status failed\n");
2818                 else {
2819                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2820                                 dev_dbg (hub_dev, "power change\n");
2821                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2822                         }
2823                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
2824                                 dev_dbg (hub_dev, "overcurrent change\n");
2825                                 msleep(500);    /* Cool down */
2826                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2827                                 hub_power_on(hub);
2828                         }
2829                 }
2830
2831                 hub->activating = 0;
2832
2833                 /* If this is a root hub, tell the HCD it's okay to
2834                  * re-enable port-change interrupts now. */
2835                 if (!hdev->parent)
2836                         usb_enable_root_hub_irq(hdev->bus);
2837
2838 loop:
2839                 usb_unlock_device(hdev);
2840                 usb_put_intf(intf);
2841
2842         } /* end while (1) */
2843 }
2844
2845 static int hub_thread(void *__unused)
2846 {
2847         do {
2848                 hub_events();
2849                 wait_event_interruptible(khubd_wait,
2850                                 !list_empty(&hub_event_list) ||
2851                                 kthread_should_stop());
2852                 try_to_freeze();
2853         } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2854
2855         pr_debug("%s: khubd exiting\n", usbcore_name);
2856         return 0;
2857 }
2858
2859 static struct usb_device_id hub_id_table [] = {
2860     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2861       .bDeviceClass = USB_CLASS_HUB},
2862     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2863       .bInterfaceClass = USB_CLASS_HUB},
2864     { }                                         /* Terminating entry */
2865 };
2866
2867 MODULE_DEVICE_TABLE (usb, hub_id_table);
2868
2869 static struct usb_driver hub_driver = {
2870         .owner =        THIS_MODULE,
2871         .name =         "hub",
2872         .probe =        hub_probe,
2873         .disconnect =   hub_disconnect,
2874         .suspend =      hub_suspend,
2875         .resume =       hub_resume,
2876         .ioctl =        hub_ioctl,
2877         .id_table =     hub_id_table,
2878 };
2879
2880 int usb_hub_init(void)
2881 {
2882         if (usb_register(&hub_driver) < 0) {
2883                 printk(KERN_ERR "%s: can't register hub driver\n",
2884                         usbcore_name);
2885                 return -1;
2886         }
2887
2888         khubd_task = kthread_run(hub_thread, NULL, "khubd");
2889         if (!IS_ERR(khubd_task))
2890                 return 0;
2891
2892         /* Fall through if kernel_thread failed */
2893         usb_deregister(&hub_driver);
2894         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2895
2896         return -1;
2897 }
2898
2899 void usb_hub_cleanup(void)
2900 {
2901         kthread_stop(khubd_task);
2902
2903         /*
2904          * Hub resources are freed for us by usb_deregister. It calls
2905          * usb_driver_purge on every device which in turn calls that
2906          * devices disconnect function if it is using this driver.
2907          * The hub_disconnect function takes care of releasing the
2908          * individual hub resources. -greg
2909          */
2910         usb_deregister(&hub_driver);
2911 } /* usb_hub_cleanup() */
2912
2913 static int config_descriptors_changed(struct usb_device *udev)
2914 {
2915         unsigned                        index;
2916         unsigned                        len = 0;
2917         struct usb_config_descriptor    *buf;
2918
2919         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2920                 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2921                         len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2922         }
2923         buf = kmalloc (len, SLAB_KERNEL);
2924         if (buf == NULL) {
2925                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2926                 /* assume the worst */
2927                 return 1;
2928         }
2929         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2930                 int length;
2931                 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2932
2933                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2934                                 old_length);
2935                 if (length < old_length) {
2936                         dev_dbg(&udev->dev, "config index %d, error %d\n",
2937                                         index, length);
2938                         break;
2939                 }
2940                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2941                                 != 0) {
2942                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2943                                 index, buf->bConfigurationValue);
2944                         break;
2945                 }
2946         }
2947         kfree(buf);
2948         return index != udev->descriptor.bNumConfigurations;
2949 }
2950
2951 /**
2952  * usb_reset_device - perform a USB port reset to reinitialize a device
2953  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2954  *
2955  * WARNING - don't reset any device unless drivers for all of its
2956  * interfaces are expecting that reset!  Maybe some driver->reset()
2957  * method should eventually help ensure sufficient cooperation.
2958  *
2959  * Do a port reset, reassign the device's address, and establish its
2960  * former operating configuration.  If the reset fails, or the device's
2961  * descriptors change from their values before the reset, or the original
2962  * configuration and altsettings cannot be restored, a flag will be set
2963  * telling khubd to pretend the device has been disconnected and then
2964  * re-connected.  All drivers will be unbound, and the device will be
2965  * re-enumerated and probed all over again.
2966  *
2967  * Returns 0 if the reset succeeded, -ENODEV if the device has been
2968  * flagged for logical disconnection, or some other negative error code
2969  * if the reset wasn't even attempted.
2970  *
2971  * The caller must own the device lock.  For example, it's safe to use
2972  * this from a driver probe() routine after downloading new firmware.
2973  * For calls that might not occur during probe(), drivers should lock
2974  * the device using usb_lock_device_for_reset().
2975  */
2976 int usb_reset_device(struct usb_device *udev)
2977 {
2978         struct usb_device               *parent_hdev = udev->parent;
2979         struct usb_hub                  *parent_hub;
2980         struct usb_device_descriptor    descriptor = udev->descriptor;
2981         struct usb_hub                  *hub = NULL;
2982         int                             i, ret = 0, port1 = -1;
2983
2984         if (udev->state == USB_STATE_NOTATTACHED ||
2985                         udev->state == USB_STATE_SUSPENDED) {
2986                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2987                                 udev->state);
2988                 return -EINVAL;
2989         }
2990
2991         if (!parent_hdev) {
2992                 /* this requires hcd-specific logic; see OHCI hc_restart() */
2993                 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2994                 return -EISDIR;
2995         }
2996
2997         for (i = 0; i < parent_hdev->maxchild; i++)
2998                 if (parent_hdev->children[i] == udev) {
2999                         port1 = i + 1;
3000                         break;
3001                 }
3002
3003         if (port1 < 0) {
3004                 /* If this ever happens, it's very bad */
3005                 dev_err(&udev->dev, "Can't locate device's port!\n");
3006                 return -ENOENT;
3007         }
3008         parent_hub = hdev_to_hub(parent_hdev);
3009
3010         /* If we're resetting an active hub, take some special actions */
3011         if (udev->actconfig &&
3012                         udev->actconfig->interface[0]->dev.driver ==
3013                                 &hub_driver.driver &&
3014                         (hub = hdev_to_hub(udev)) != NULL) {
3015                 hub_pre_reset(hub);
3016         }
3017
3018         set_bit(port1, parent_hub->busy_bits);
3019         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
3020
3021                 /* ep0 maxpacket size may change; let the HCD know about it.
3022                  * Other endpoints will be handled by re-enumeration. */
3023                 ep0_reinit(udev);
3024                 ret = hub_port_init(parent_hub, udev, port1, i);
3025                 if (ret >= 0)
3026                         break;
3027         }
3028         clear_bit(port1, parent_hub->busy_bits);
3029         if (ret < 0)
3030                 goto re_enumerate;
3031
3032         /* Device might have changed firmware (DFU or similar) */
3033         if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
3034                         || config_descriptors_changed (udev)) {
3035                 dev_info(&udev->dev, "device firmware changed\n");
3036                 udev->descriptor = descriptor;  /* for disconnect() calls */
3037                 goto re_enumerate;
3038         }
3039
3040         if (!udev->actconfig)
3041                 goto done;
3042
3043         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3044                         USB_REQ_SET_CONFIGURATION, 0,
3045                         udev->actconfig->desc.bConfigurationValue, 0,
3046                         NULL, 0, USB_CTRL_SET_TIMEOUT);
3047         if (ret < 0) {
3048                 dev_err(&udev->dev,
3049                         "can't restore configuration #%d (error=%d)\n",
3050                         udev->actconfig->desc.bConfigurationValue, ret);
3051                 goto re_enumerate;
3052         }
3053         usb_set_device_state(udev, USB_STATE_CONFIGURED);
3054
3055         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3056                 struct usb_interface *intf = udev->actconfig->interface[i];
3057                 struct usb_interface_descriptor *desc;
3058
3059                 /* set_interface resets host side toggle even
3060                  * for altsetting zero.  the interface may have no driver.
3061                  */
3062                 desc = &intf->cur_altsetting->desc;
3063                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3064                         desc->bAlternateSetting);
3065                 if (ret < 0) {
3066                         dev_err(&udev->dev, "failed to restore interface %d "
3067                                 "altsetting %d (error=%d)\n",
3068                                 desc->bInterfaceNumber,
3069                                 desc->bAlternateSetting,
3070                                 ret);
3071                         goto re_enumerate;
3072                 }
3073         }
3074
3075 done:
3076         if (hub)
3077                 hub_post_reset(hub);
3078         return 0;
3079
3080 re_enumerate:
3081         hub_port_logical_disconnect(parent_hub, port1);
3082         return -ENODEV;
3083 }