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         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
 631         switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_TTTT) {
 632                 case HUB_TTTT_8_BITS:
 633                         if (hdev->descriptor.bDeviceProtocol != 0) {
 634                                 hub->tt.think_time = 666;
 635                                 dev_dbg(hub_dev, "TT requires at most %d "
 636                                                 "FS bit times (%d ns)\n",
 637                                         8, hub->tt.think_time);
 638                         }
 639                         break;
 640                 case HUB_TTTT_16_BITS:
 641                         hub->tt.think_time = 666 * 2;
 642                         dev_dbg(hub_dev, "TT requires at most %d "
 643                                         "FS bit times (%d ns)\n",
 644                                 16, hub->tt.think_time);
 645                         break;
 646                 case HUB_TTTT_24_BITS:
 647                         hub->tt.think_time = 666 * 3;
 648                         dev_dbg(hub_dev, "TT requires at most %d "
 649                                         "FS bit times (%d ns)\n",
 650                                 24, hub->tt.think_time);
 651                         break;
 652                 case HUB_TTTT_32_BITS:
 653                         hub->tt.think_time = 666 * 4;
 654                         dev_dbg(hub_dev, "TT requires at most %d "
 655                                         "FS bit times (%d ns)\n",
 656                                 32, hub->tt.think_time);
 657                         break;
 658         }
 659
 660         /* probe() zeroes hub->indicator[] */
 661         if (hub->descriptor->wHubCharacteristics & HUB_CHAR_PORTIND) {
 662                 hub->has_indicators = 1;
 663                 dev_dbg(hub_dev, "Port indicators are supported\n");
 664         }
 665
 666         dev_dbg(hub_dev, "power on to power good time: %dms\n",
 667                 hub->descriptor->bPwrOn2PwrGood * 2);
 668
 669         /* power budgeting mostly matters with bus-powered hubs,
 670          * and battery-powered root hubs (may provide just 8 mA).
 671          */
 672         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
 673         if (ret < 0) {
 674                 message = "can't get hub status";
 675                 goto fail;
 676         }
 677         le16_to_cpus(&hubstatus);
 678         if (hdev == hdev->bus->root_hub) {
 679                 struct usb_hcd *hcd =
 680                                 container_of(hdev->bus, struct usb_hcd, self);
 681
 682                 hub->power_budget = min(500u, hcd->power_budget) / 2;
 683         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
 684                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
 685                         hub->descriptor->bHubContrCurrent);
 686                 hub->power_budget = (501 - hub->descriptor->bHubContrCurrent)
 687                                         / 2;
 688         }
 689         if (hub->power_budget)
 690                 dev_dbg(hub_dev, "%dmA bus power budget for children\n",
 691                         hub->power_budget * 2);
 692
 693
 694         ret = hub_hub_status(hub, &hubstatus, &hubchange);
 695         if (ret < 0) {
 696                 message = "can't get hub status";
 697                 goto fail;
 698         }
 699
 700         /* local power status reports aren't always correct */
 701         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
 702                 dev_dbg(hub_dev, "local power source is %s\n",
 703                         (hubstatus & HUB_STATUS_LOCAL_POWER)
 704                         ? "lost (inactive)" : "good");
 705
 706         if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) == 0)
 707                 dev_dbg(hub_dev, "%sover-current condition exists\n",
 708                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
 709
 710         /* set up the interrupt endpoint */
 711         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
 712         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
 713
 714         if (maxp > sizeof(*hub->buffer))
 715                 maxp = sizeof(*hub->buffer);
 716
 717         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
 718         if (!hub->urb) {
 719                 message = "couldn't allocate interrupt urb";
 720                 ret = -ENOMEM;
 721                 goto fail;
 722         }
 723
 724         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
 725                 hub, endpoint->bInterval);
 726         hub->urb->transfer_dma = hub->buffer_dma;
 727         hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 728
 729         /* maybe cycle the hub leds */
 730         if (hub->has_indicators && blinkenlights)
 731                 hub->indicator [0] = INDICATOR_CYCLE;
 732
 733         hub_power_on(hub);
 734         hub_activate(hub);
 735         return 0;
 736
 737 fail:
 738         dev_err (hub_dev, "config failed, %s (err %d)\n",
 739                         message, ret);
 740         /* hub_disconnect() frees urb and descriptor */
 741         return ret;
 742 }
 743
 744 static unsigned highspeed_hubs;
 745
 746 /* Called after the hub driver is unbound from a hub with children */
 747 static void hub_remove_children_work(void *__hub)
 748 {
 749         struct usb_hub          *hub = __hub;
 750         struct usb_device       *hdev = hub->hdev;
 751         int                     i;
 752
 753         kfree(hub);
 754
 755         usb_lock_device(hdev);
 756         for (i = 0; i < hdev->maxchild; ++i) {
 757                 if (hdev->children[i])
 758                         usb_disconnect(&hdev->children[i]);
 759         }
 760         usb_unlock_device(hdev);
 761         usb_put_dev(hdev);
 762 }
 763
 764 static void hub_disconnect(struct usb_interface *intf)
 765 {
 766         struct usb_hub *hub = usb_get_intfdata (intf);
 767         struct usb_device *hdev;
 768         int n, port1;
 769
 770         usb_set_intfdata (intf, NULL);
 771         hdev = hub->hdev;
 772
 773         if (hdev->speed == USB_SPEED_HIGH)
 774                 highspeed_hubs--;
 775
 776         hub_quiesce(hub);
 777         usb_free_urb(hub->urb);
 778         hub->urb = NULL;
 779
 780         spin_lock_irq(&hub_event_lock);
 781         list_del_init(&hub->event_list);
 782         spin_unlock_irq(&hub_event_lock);
 783
 784         kfree(hub->descriptor);
 785         hub->descriptor = NULL;
 786
 787         kfree(hub->status);
 788         hub->status = NULL;
 789
 790         if (hub->buffer) {
 791                 usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
 792                                 hub->buffer_dma);
 793                 hub->buffer = NULL;
 794         }
 795
 796         /* If there are any children then this is an unbind only, not a
 797          * physical disconnection.  The active ports must be disabled
 798          * and later on we must call usb_disconnect().  We can't call
 799          * it now because we may not hold the hub's device lock.
 800          */
 801         n = 0;
 802         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
 803                 if (hdev->children[port1 - 1]) {
 804                         ++n;
 805                         hub_port_disable(hub, port1, 1);
 806                 }
 807         }
 808
 809         if (n == 0)
 810                 kfree(hub);
 811         else {
 812                 /* Reuse the hub->leds work_struct for our own purposes */
 813                 INIT_WORK(&hub->leds, hub_remove_children_work, hub);
 814                 schedule_work(&hub->leds);
 815                 usb_get_dev(hdev);
 816         }
 817 }
 818
 819 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
 820 {
 821         struct usb_host_interface *desc;
 822         struct usb_endpoint_descriptor *endpoint;
 823         struct usb_device *hdev;
 824         struct usb_hub *hub;
 825
 826         desc = intf->cur_altsetting;
 827         hdev = interface_to_usbdev(intf);
 828
 829         /* Some hubs have a subclass of 1, which AFAICT according to the */
 830         /*  specs is not defined, but it works */
 831         if ((desc->desc.bInterfaceSubClass != 0) &&
 832             (desc->desc.bInterfaceSubClass != 1)) {
 833 descriptor_error:
 834                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
 835                 return -EIO;
 836         }
 837
 838         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
 839         if (desc->desc.bNumEndpoints != 1)
 840                 goto descriptor_error;
 841
 842         endpoint = &desc->endpoint[0].desc;
 843
 844         /* Output endpoint? Curiouser and curiouser.. */
 845         if (!(endpoint->bEndpointAddress & USB_DIR_IN))
 846                 goto descriptor_error;
 847
 848         /* If it's not an interrupt endpoint, we'd better punt! */
 849         if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
 850                         != USB_ENDPOINT_XFER_INT)
 851                 goto descriptor_error;
 852
 853         /* We found a hub */
 854         dev_info (&intf->dev, "USB hub found\n");
 855
 856         hub = kmalloc(sizeof(*hub), GFP_KERNEL);
 857         if (!hub) {
 858                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
 859                 return -ENOMEM;
 860         }
 861
 862         memset(hub, 0, sizeof(*hub));
 863
 864         INIT_LIST_HEAD(&hub->event_list);
 865         hub->intfdev = &intf->dev;
 866         hub->hdev = hdev;
 867         INIT_WORK(&hub->leds, led_work, hub);
 868
 869         usb_set_intfdata (intf, hub);
 870
 871         if (hdev->speed == USB_SPEED_HIGH)
 872                 highspeed_hubs++;
 873
 874         if (hub_configure(hub, endpoint) >= 0)
 875                 return 0;
 876
 877         hub_disconnect (intf);
 878         return -ENODEV;
 879 }
 880
 881 static int
 882 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
 883 {
 884         struct usb_device *hdev = interface_to_usbdev (intf);
 885
 886         /* assert ifno == 0 (part of hub spec) */
 887         switch (code) {
 888         case USBDEVFS_HUB_PORTINFO: {
 889                 struct usbdevfs_hub_portinfo *info = user_data;
 890                 int i;
 891
 892                 spin_lock_irq(&device_state_lock);
 893                 if (hdev->devnum <= 0)
 894                         info->nports = 0;
 895                 else {
 896                         info->nports = hdev->maxchild;
 897                         for (i = 0; i < info->nports; i++) {
 898                                 if (hdev->children[i] == NULL)
 899                                         info->port[i] = 0;
 900                                 else
 901                                         info->port[i] =
 902                                                 hdev->children[i]->devnum;
 903                         }
 904                 }
 905                 spin_unlock_irq(&device_state_lock);
 906
 907                 return info->nports + 1;
 908                 }
 909
 910         default:
 911                 return -ENOSYS;
 912         }
 913 }
 914
 915 /* caller has locked the hub device */
 916 static void hub_pre_reset(struct usb_hub *hub)
 917 {
 918         struct usb_device *hdev = hub->hdev;
 919         int i;
 920
 921         for (i = 0; i < hdev->maxchild; ++i) {
 922                 if (hdev->children[i])
 923                         usb_disconnect(&hdev->children[i]);
 924         }
 925         hub_quiesce(hub);
 926 }
 927
 928 /* caller has locked the hub device */
 929 static void hub_post_reset(struct usb_hub *hub)
 930 {
 931         hub_activate(hub);
 932         hub_power_on(hub);
 933 }
 934
 935
 936 /* grab device/port lock, returning index of that port (zero based).
 937  * protects the upstream link used by this device from concurrent
 938  * tree operations like suspend, resume, reset, and disconnect, which
 939  * apply to everything downstream of a given port.
 940  */
 941 static int locktree(struct usb_device *udev)
 942 {
 943         int                     t;
 944         struct usb_device       *hdev;
 945
 946         if (!udev)
 947                 return -ENODEV;
 948
 949         /* root hub is always the first lock in the series */
 950         hdev = udev->parent;
 951         if (!hdev) {
 952                 usb_lock_device(udev);
 953                 return 0;
 954         }
 955
 956         /* on the path from root to us, lock everything from
 957          * top down, dropping parent locks when not needed
 958          */
 959         t = locktree(hdev);
 960         if (t < 0)
 961                 return t;
 962         for (t = 0; t < hdev->maxchild; t++) {
 963                 if (hdev->children[t] == udev) {
 964                         /* everything is fail-fast once disconnect
 965                          * processing starts
 966                          */
 967                         if (udev->state == USB_STATE_NOTATTACHED)
 968                                 break;
 969
 970                         /* when everyone grabs locks top->bottom,
 971                          * non-overlapping work may be concurrent
 972                          */
 973                         down(&udev->serialize);
 974                         up(&hdev->serialize);
 975                         return t + 1;
 976                 }
 977         }
 978         usb_unlock_device(hdev);
 979         return -ENODEV;
 980 }
 981
 982 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
 983 {
 984         int i;
 985
 986         for (i = 0; i < udev->maxchild; ++i) {
 987                 if (udev->children[i])
 988                         recursively_mark_NOTATTACHED(udev->children[i]);
 989         }
 990         udev->state = USB_STATE_NOTATTACHED;
 991 }
 992
 993 /**
 994  * usb_set_device_state - change a device's current state (usbcore, hcds)
 995  * @udev: pointer to device whose state should be changed
 996  * @new_state: new state value to be stored
 997  *
 998  * udev->state is _not_ fully protected by the device lock.  Although
 999  * most transitions are made only while holding the lock, the state can
1000  * can change to USB_STATE_NOTATTACHED at almost any time.  This
1001  * is so that devices can be marked as disconnected as soon as possible,
1002  * without having to wait for any semaphores to be released.  As a result,
1003  * all changes to any device's state must be protected by the
1004  * device_state_lock spinlock.
1005  *
1006  * Once a device has been added to the device tree, all changes to its state
1007  * should be made using this routine.  The state should _not_ be set directly.
1008  *
1009  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1010  * Otherwise udev->state is set to new_state, and if new_state is
1011  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1012  * to USB_STATE_NOTATTACHED.
1013  */
1014 void usb_set_device_state(struct usb_device *udev,
1015                 enum usb_device_state new_state)
1016 {
1017         unsigned long flags;
1018
1019         spin_lock_irqsave(&device_state_lock, flags);
1020         if (udev->state == USB_STATE_NOTATTACHED)
1021                 ;       /* do nothing */
1022         else if (new_state != USB_STATE_NOTATTACHED)
1023                 udev->state = new_state;
1024         else
1025                 recursively_mark_NOTATTACHED(udev);
1026         spin_unlock_irqrestore(&device_state_lock, flags);
1027 }
1028 EXPORT_SYMBOL(usb_set_device_state);
1029
1030
1031 static void choose_address(struct usb_device *udev)
1032 {
1033         int             devnum;
1034         struct usb_bus  *bus = udev->bus;
1035
1036         /* If khubd ever becomes multithreaded, this will need a lock */
1037
1038         /* Try to allocate the next devnum beginning at bus->devnum_next. */
1039         devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1040                         bus->devnum_next);
1041         if (devnum >= 128)
1042                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1043
1044         bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1045
1046         if (devnum < 128) {
1047                 set_bit(devnum, bus->devmap.devicemap);
1048                 udev->devnum = devnum;
1049         }
1050 }
1051
1052 static void release_address(struct usb_device *udev)
1053 {
1054         if (udev->devnum > 0) {
1055                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1056                 udev->devnum = -1;
1057         }
1058 }
1059
1060 /**
1061  * usb_disconnect - disconnect a device (usbcore-internal)
1062  * @pdev: pointer to device being disconnected
1063  * Context: !in_interrupt ()
1064  *
1065  * Something got disconnected. Get rid of it and all of its children.
1066  *
1067  * If *pdev is a normal device then the parent hub must already be locked.
1068  * If *pdev is a root hub then this routine will acquire the
1069  * usb_bus_list_lock on behalf of the caller.
1070  *
1071  * Only hub drivers (including virtual root hub drivers for host
1072  * controllers) should ever call this.
1073  *
1074  * This call is synchronous, and may not be used in an interrupt context.
1075  */
1076 void usb_disconnect(struct usb_device **pdev)
1077 {
1078         struct usb_device       *udev = *pdev;
1079         int                     i;
1080
1081         if (!udev) {
1082                 pr_debug ("%s nodev\n", __FUNCTION__);
1083                 return;
1084         }
1085
1086         /* mark the device as inactive, so any further urb submissions for
1087          * this device (and any of its children) will fail immediately.
1088          * this quiesces everyting except pending urbs.
1089          */
1090         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1091
1092         /* lock the bus list on behalf of HCDs unregistering their root hubs */
1093         if (!udev->parent) {
1094                 down(&usb_bus_list_lock);
1095                 usb_lock_device(udev);
1096         } else
1097                 down(&udev->serialize);
1098
1099         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1100
1101         /* Free up all the children before we remove this device */
1102         for (i = 0; i < USB_MAXCHILDREN; i++) {
1103                 if (udev->children[i])
1104                         usb_disconnect(&udev->children[i]);
1105         }
1106
1107         /* deallocate hcd/hardware state ... nuking all pending urbs and
1108          * cleaning up all state associated with the current configuration
1109          * so that the hardware is now fully quiesced.
1110          */
1111         usb_disable_device(udev, 0);
1112
1113         /* Free the device number, remove the /proc/bus/usb entry and
1114          * the sysfs attributes, and delete the parent's children[]
1115          * (or root_hub) pointer.
1116          */
1117         dev_dbg (&udev->dev, "unregistering device\n");
1118         release_address(udev);
1119         usbfs_remove_device(udev);
1120         usbdev_remove(udev);
1121         usb_remove_sysfs_dev_files(udev);
1122
1123         /* Avoid races with recursively_mark_NOTATTACHED() */
1124         spin_lock_irq(&device_state_lock);
1125         *pdev = NULL;
1126         spin_unlock_irq(&device_state_lock);
1127
1128         if (!udev->parent) {
1129                 usb_unlock_device(udev);
1130                 up(&usb_bus_list_lock);
1131         } else
1132                 up(&udev->serialize);
1133
1134         device_unregister(&udev->dev);
1135 }
1136
1137 static int choose_configuration(struct usb_device *udev)
1138 {
1139         int c, i;
1140
1141         /* NOTE: this should interact with hub power budgeting */
1142
1143         c = udev->config[0].desc.bConfigurationValue;
1144         if (udev->descriptor.bNumConfigurations != 1) {
1145                 for (i = 0; i < udev->descriptor.bNumConfigurations; i++) {
1146                         struct usb_interface_descriptor *desc;
1147
1148                         /* heuristic:  Linux is more likely to have class
1149                          * drivers, so avoid vendor-specific interfaces.
1150                          */
1151                         desc = &udev->config[i].intf_cache[0]
1152                                         ->altsetting->desc;
1153                         if (desc->bInterfaceClass == USB_CLASS_VENDOR_SPEC)
1154                                 continue;
1155                         /* COMM/2/all is CDC ACM, except 0xff is MSFT RNDIS.
1156                          * MSFT needs this to be the first config; never use
1157                          * it as the default unless Linux has host-side RNDIS.
1158                          * A second config would ideally be CDC-Ethernet, but
1159                          * may instead be the "vendor specific" CDC subset
1160                          * long used by ARM Linux for sa1100 or pxa255.
1161                          */
1162                         if (desc->bInterfaceClass == USB_CLASS_COMM
1163                                         && desc->bInterfaceSubClass == 2
1164                                         && desc->bInterfaceProtocol == 0xff) {
1165                                 c = udev->config[1].desc.bConfigurationValue;
1166                                 continue;
1167                         }
1168                         c = udev->config[i].desc.bConfigurationValue;
1169                         break;
1170                 }
1171                 dev_info(&udev->dev,
1172                         "configuration #%d chosen from %d choices\n",
1173                         c, udev->descriptor.bNumConfigurations);
1174         }
1175         return c;
1176 }
1177
1178 #ifdef DEBUG
1179 static void show_string(struct usb_device *udev, char *id, char *string)
1180 {
1181         if (!string)
1182                 return;
1183         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1184 }
1185
1186 #else
1187 static inline void show_string(struct usb_device *udev, char *id, char *string)
1188 {}
1189 #endif
1190
1191 static void get_string(struct usb_device *udev, char **string, int index)
1192 {
1193         char *buf;
1194
1195         if (!index)
1196                 return;
1197         buf = kmalloc(256, GFP_KERNEL);
1198         if (!buf)
1199                 return;
1200         if (usb_string(udev, index, buf, 256) > 0)
1201                 *string = buf;
1202         else
1203                 kfree(buf);
1204 }
1205
1206
1207 #ifdef  CONFIG_USB_OTG
1208 #include "otg_whitelist.h"
1209 #endif
1210
1211 /**
1212  * usb_new_device - perform initial device setup (usbcore-internal)
1213  * @udev: newly addressed device (in ADDRESS state)
1214  *
1215  * This is called with devices which have been enumerated, but not yet
1216  * configured.  The device descriptor is available, but not descriptors
1217  * for any device configuration.  The caller must have locked udev and
1218  * either the parent hub (if udev is a normal device) or else the
1219  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1220  * udev has already been installed, but udev is not yet visible through
1221  * sysfs or other filesystem code.
1222  *
1223  * Returns 0 for success (device is configured and listed, with its
1224  * interfaces, in sysfs); else a negative errno value.
1225  *
1226  * This call is synchronous, and may not be used in an interrupt context.
1227  *
1228  * Only the hub driver should ever call this; root hub registration
1229  * uses it indirectly.
1230  */
1231 int usb_new_device(struct usb_device *udev)
1232 {
1233         int err;
1234         int c;
1235
1236         err = usb_get_configuration(udev);
1237         if (err < 0) {
1238                 dev_err(&udev->dev, "can't read configurations, error %d\n",
1239                         err);
1240                 goto fail;
1241         }
1242
1243         /* read the standard strings and cache them if present */
1244         get_string(udev, &udev->product, udev->descriptor.iProduct);
1245         get_string(udev, &udev->manufacturer, udev->descriptor.iManufacturer);
1246         get_string(udev, &udev->serial, udev->descriptor.iSerialNumber);
1247
1248         /* Tell the world! */
1249         dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1250                         "SerialNumber=%d\n",
1251                         udev->descriptor.iManufacturer,
1252                         udev->descriptor.iProduct,
1253                         udev->descriptor.iSerialNumber);
1254         show_string(udev, "Product", udev->product);
1255         show_string(udev, "Manufacturer", udev->manufacturer);
1256         show_string(udev, "SerialNumber", udev->serial);
1257
1258 #ifdef  CONFIG_USB_OTG
1259         /*
1260          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1261          * to wake us after we've powered off VBUS; and HNP, switching roles
1262          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1263          */
1264         if (!udev->bus->is_b_host
1265                         && udev->config
1266                         && udev->parent == udev->bus->root_hub) {
1267                 struct usb_otg_descriptor       *desc = 0;
1268                 struct usb_bus                  *bus = udev->bus;
1269
1270                 /* descriptor may appear anywhere in config */
1271                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1272                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1273                                         USB_DT_OTG, (void **) &desc) == 0) {
1274                         if (desc->bmAttributes & USB_OTG_HNP) {
1275                                 unsigned                port1;
1276                                 struct usb_device       *root = udev->parent;
1277
1278                                 for (port1 = 1; port1 <= root->maxchild;
1279                                                 port1++) {
1280                                         if (root->children[port1-1] == udev)
1281                                                 break;
1282                                 }
1283
1284                                 dev_info(&udev->dev,
1285                                         "Dual-Role OTG device on %sHNP port\n",
1286                                         (port1 == bus->otg_port)
1287                                                 ? "" : "non-");
1288
1289                                 /* enable HNP before suspend, it's simpler */
1290                                 if (port1 == bus->otg_port)
1291                                         bus->b_hnp_enable = 1;
1292                                 err = usb_control_msg(udev,
1293                                         usb_sndctrlpipe(udev, 0),
1294                                         USB_REQ_SET_FEATURE, 0,
1295                                         bus->b_hnp_enable
1296                                                 ? USB_DEVICE_B_HNP_ENABLE
1297                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1298                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1299                                 if (err < 0) {
1300                                         /* OTG MESSAGE: report errors here,
1301                                          * customize to match your product.
1302                                          */
1303                                         dev_info(&udev->dev,
1304                                                 "can't set HNP mode; %d\n",
1305                                                 err);
1306                                         bus->b_hnp_enable = 0;
1307                                 }
1308                         }
1309                 }
1310         }
1311
1312         if (!is_targeted(udev)) {
1313
1314                 /* Maybe it can talk to us, though we can't talk to it.
1315                  * (Includes HNP test device.)
1316                  */
1317                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1318                         static int __usb_suspend_device (struct usb_device *,
1319                                                 int port1, pm_message_t state);
1320                         err = __usb_suspend_device(udev,
1321                                         udev->bus->otg_port,
1322                                         PMSG_SUSPEND);
1323                         if (err < 0)
1324                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1325                 }
1326                 err = -ENODEV;
1327                 goto fail;
1328         }
1329 #endif
1330
1331         /* put device-specific files into sysfs */
1332         err = device_add (&udev->dev);
1333         if (err) {
1334                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1335                 goto fail;
1336         }
1337         usb_create_sysfs_dev_files (udev);
1338
1339         /* choose and set the configuration. that registers the interfaces
1340          * with the driver core, and lets usb device drivers bind to them.
1341          */
1342         c = choose_configuration(udev);
1343         if (c < 0)
1344                 dev_warn(&udev->dev,
1345                                 "can't choose an initial configuration\n");
1346         else {
1347                 err = usb_set_configuration(udev, c);
1348                 if (err) {
1349                         dev_err(&udev->dev, "can't set config #%d, error %d\n",
1350                                         c, err);
1351                         usb_remove_sysfs_dev_files(udev);
1352                         device_del(&udev->dev);
1353                         goto fail;
1354                 }
1355         }
1356
1357         /* USB device state == configured ... usable */
1358
1359         /* add a /proc/bus/usb entry */
1360         usbdev_add(udev);
1361         usbfs_add_device(udev);
1362         return 0;
1363
1364 fail:
1365         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1366         return err;
1367 }
1368
1369
1370 static int hub_port_status(struct usb_hub *hub, int port1,
1371                                u16 *status, u16 *change)
1372 {
1373         int ret;
1374
1375         ret = get_port_status(hub->hdev, port1, &hub->status->port);
1376         if (ret < 0)
1377                 dev_err (hub->intfdev,
1378                         "%s failed (err = %d)\n", __FUNCTION__, ret);
1379         else {
1380                 *status = le16_to_cpu(hub->status->port.wPortStatus);
1381                 *change = le16_to_cpu(hub->status->port.wPortChange);
1382                 ret = 0;
1383         }
1384         return ret;
1385 }
1386
1387 #define PORT_RESET_TRIES        5
1388 #define SET_ADDRESS_TRIES       2
1389 #define GET_DESCRIPTOR_TRIES    2
1390 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1391 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1392
1393 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1394 #define HUB_SHORT_RESET_TIME    10
1395 #define HUB_LONG_RESET_TIME     200
1396 #define HUB_RESET_TIMEOUT       500
1397
1398 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1399                                 struct usb_device *udev, unsigned int delay)
1400 {
1401         int delay_time, ret;
1402         u16 portstatus;
1403         u16 portchange;
1404
1405         for (delay_time = 0;
1406                         delay_time < HUB_RESET_TIMEOUT;
1407                         delay_time += delay) {
1408                 /* wait to give the device a chance to reset */
1409                 msleep(delay);
1410
1411                 /* read and decode port status */
1412                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1413                 if (ret < 0)
1414                         return ret;
1415
1416                 /* Device went away? */
1417                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1418                         return -ENOTCONN;
1419
1420                 /* bomb out completely if something weird happened */
1421                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1422                         return -EINVAL;
1423
1424                 /* if we`ve finished resetting, then break out of the loop */
1425                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1426                     (portstatus & USB_PORT_STAT_ENABLE)) {
1427                         if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1428                                 udev->speed = USB_SPEED_HIGH;
1429                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1430                                 udev->speed = USB_SPEED_LOW;
1431                         else
1432                                 udev->speed = USB_SPEED_FULL;
1433                         return 0;
1434                 }
1435
1436                 /* switch to the long delay after two short delay failures */
1437                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1438                         delay = HUB_LONG_RESET_TIME;
1439
1440                 dev_dbg (hub->intfdev,
1441                         "port %d not reset yet, waiting %dms\n",
1442                         port1, delay);
1443         }
1444
1445         return -EBUSY;
1446 }
1447
1448 static int hub_port_reset(struct usb_hub *hub, int port1,
1449                                 struct usb_device *udev, unsigned int delay)
1450 {
1451         int i, status;
1452
1453         /* Reset the port */
1454         for (i = 0; i < PORT_RESET_TRIES; i++) {
1455                 status = set_port_feature(hub->hdev,
1456                                 port1, USB_PORT_FEAT_RESET);
1457                 if (status)
1458                         dev_err(hub->intfdev,
1459                                         "cannot reset port %d (err = %d)\n",
1460                                         port1, status);
1461                 else {
1462                         status = hub_port_wait_reset(hub, port1, udev, delay);
1463                         if (status)
1464                                 dev_dbg(hub->intfdev,
1465                                                 "port_wait_reset: err = %d\n",
1466                                                 status);
1467                 }
1468
1469                 /* return on disconnect or reset */
1470                 switch (status) {
1471                 case 0:
1472                         /* TRSTRCY = 10 ms */
1473                         msleep(10);
1474                         /* FALL THROUGH */
1475                 case -ENOTCONN:
1476                 case -ENODEV:
1477                         clear_port_feature(hub->hdev,
1478                                 port1, USB_PORT_FEAT_C_RESET);
1479                         /* FIXME need disconnect() for NOTATTACHED device */
1480                         usb_set_device_state(udev, status
1481                                         ? USB_STATE_NOTATTACHED
1482                                         : USB_STATE_DEFAULT);
1483                         return status;
1484                 }
1485
1486                 dev_dbg (hub->intfdev,
1487                         "port %d not enabled, trying reset again...\n",
1488                         port1);
1489                 delay = HUB_LONG_RESET_TIME;
1490         }
1491
1492         dev_err (hub->intfdev,
1493                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1494                 port1);
1495
1496         return status;
1497 }
1498
1499 /*
1500  * Disable a port and mark a logical connnect-change event, so that some
1501  * time later khubd will disconnect() any existing usb_device on the port
1502  * and will re-enumerate if there actually is a device attached.
1503  */
1504 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1505 {
1506         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1507         hub_port_disable(hub, port1, 1);
1508
1509         /* FIXME let caller ask to power down the port:
1510          *  - some devices won't enumerate without a VBUS power cycle
1511          *  - SRP saves power that way
1512          *  - usb_suspend_device(dev, PMSG_SUSPEND)
1513          * That's easy if this hub can switch power per-port, and
1514          * khubd reactivates the port later (timer, SRP, etc).
1515          * Powerdown must be optional, because of reset/DFU.
1516          */
1517
1518         set_bit(port1, hub->change_bits);
1519         kick_khubd(hub);
1520 }
1521
1522
1523 #ifdef  CONFIG_USB_SUSPEND
1524
1525 /*
1526  * Selective port suspend reduces power; most suspended devices draw
1527  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1528  * All devices below the suspended port are also suspended.
1529  *
1530  * Devices leave suspend state when the host wakes them up.  Some devices
1531  * also support "remote wakeup", where the device can activate the USB
1532  * tree above them to deliver data, such as a keypress or packet.  In
1533  * some cases, this wakes the USB host.
1534  */
1535 static int hub_port_suspend(struct usb_hub *hub, int port1,
1536                 struct usb_device *udev)
1537 {
1538         int     status;
1539
1540         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1541
1542         /* enable remote wakeup when appropriate; this lets the device
1543          * wake up the upstream hub (including maybe the root hub).
1544          *
1545          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1546          * we don't explicitly enable it here.
1547          */
1548         if (udev->actconfig
1549                         // && FIXME (remote wakeup enabled on this bus)
1550                         // ... currently assuming it's always appropriate
1551                         && (udev->actconfig->desc.bmAttributes
1552                                 & USB_CONFIG_ATT_WAKEUP) != 0) {
1553                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1554                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1555                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1556                                 NULL, 0,
1557                                 USB_CTRL_SET_TIMEOUT);
1558                 if (status)
1559                         dev_dbg(&udev->dev,
1560                                 "won't remote wakeup, status %d\n",
1561                                 status);
1562         }
1563
1564         /* see 7.1.7.6 */
1565         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1566         if (status) {
1567                 dev_dbg(hub->intfdev,
1568                         "can't suspend port %d, status %d\n",
1569                         port1, status);
1570                 /* paranoia:  "should not happen" */
1571                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1572                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1573                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1574                                 NULL, 0,
1575                                 USB_CTRL_SET_TIMEOUT);
1576         } else {
1577                 /* device has up to 10 msec to fully suspend */
1578                 dev_dbg(&udev->dev, "usb suspend\n");
1579                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1580                 msleep(10);
1581         }
1582         return status;
1583 }
1584
1585 /*
1586  * Devices on USB hub ports have only one "suspend" state, corresponding
1587  * to ACPI D2, "may cause the device to lose some context".
1588  * State transitions include:
1589  *
1590  *   - suspend, resume ... when the VBUS power link stays live
1591  *   - suspend, disconnect ... VBUS lost
1592  *
1593  * Once VBUS drop breaks the circuit, the port it's using has to go through
1594  * normal re-enumeration procedures, starting with enabling VBUS power.
1595  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1596  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1597  * timer, no SRP, no requests through sysfs.
1598  */
1599 static int __usb_suspend_device (struct usb_device *udev, int port1,
1600                                  pm_message_t state)
1601 {
1602         int     status;
1603
1604         /* caller owns the udev device lock */
1605         if (port1 < 0)
1606                 return port1;
1607
1608         if (udev->state == USB_STATE_SUSPENDED
1609                         || udev->state == USB_STATE_NOTATTACHED) {
1610                 return 0;
1611         }
1612
1613         /* suspend interface drivers; if this is a hub, it
1614          * suspends the child devices
1615          */
1616         if (udev->actconfig) {
1617                 int     i;
1618
1619                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1620                         struct usb_interface    *intf;
1621                         struct usb_driver       *driver;
1622
1623                         intf = udev->actconfig->interface[i];
1624                         if (state.event <= intf->dev.power.power_state.event)
1625                                 continue;
1626                         if (!intf->dev.driver)
1627                                 continue;
1628                         driver = to_usb_driver(intf->dev.driver);
1629
1630                         if (driver->suspend) {
1631                                 status = driver->suspend(intf, state);
1632                                 if (intf->dev.power.power_state.event != state.event
1633                                                 || status)
1634                                         dev_err(&intf->dev,
1635                                                 "suspend %d fail, code %d\n",
1636                                                 state.event, status);
1637                         }
1638
1639                         /* only drivers with suspend() can ever resume();
1640                          * and after power loss, even they won't.
1641                          * bus_rescan_devices() can rebind drivers later.
1642                          *
1643                          * FIXME the PM core self-deadlocks when unbinding
1644                          * drivers during suspend/resume ... everything grabs
1645                          * dpm_sem (not a spinlock, ugh).  we want to unbind,
1646                          * since we know every driver's probe/disconnect works
1647                          * even for drivers that can't suspend.
1648                          */
1649                         if (!driver->suspend || state.event > PM_EVENT_FREEZE) {
1650 #if 1
1651                                 dev_warn(&intf->dev, "resume is unsafe!\n");
1652 #else
1653                                 down_write(&usb_bus_type.rwsem);
1654                                 device_release_driver(&intf->dev);
1655                                 up_write(&usb_bus_type.rwsem);
1656 #endif
1657                         }
1658                 }
1659         }
1660
1661         /*
1662          * FIXME this needs port power off call paths too, to help force
1663          * USB into the "generic" PM model.  At least for devices on
1664          * ports that aren't using ganged switching (usually root hubs).
1665          *
1666          * NOTE: SRP-capable links should adopt more aggressive poweroff
1667          * policies (when HNP doesn't apply) once we have mechanisms to
1668          * turn power back on!  (Likely not before 2.7...)
1669          */
1670         if (state.event > PM_EVENT_FREEZE) {
1671                 dev_warn(&udev->dev, "no poweroff yet, suspending instead\n");
1672         }
1673
1674         /* "global suspend" of the HC-to-USB interface (root hub), or
1675          * "selective suspend" of just one hub-device link.
1676          */
1677         if (!udev->parent) {
1678                 struct usb_bus  *bus = udev->bus;
1679                 if (bus && bus->op->hub_suspend) {
1680                         status = bus->op->hub_suspend (bus);
1681                         if (status == 0) {
1682                                 dev_dbg(&udev->dev, "usb suspend\n");
1683                                 usb_set_device_state(udev,
1684                                                 USB_STATE_SUSPENDED);
1685                         }
1686                 } else
1687                         status = -EOPNOTSUPP;
1688         } else
1689                 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1690                                 udev);
1691
1692         if (status == 0)
1693                 udev->dev.power.power_state = state;
1694         return status;
1695 }
1696
1697 /**
1698  * usb_suspend_device - suspend a usb device
1699  * @udev: device that's no longer in active use
1700  * @state: PMSG_SUSPEND to suspend
1701  * Context: must be able to sleep; device not locked
1702  *
1703  * Suspends a USB device that isn't in active use, conserving power.
1704  * Devices may wake out of a suspend, if anything important happens,
1705  * using the remote wakeup mechanism.  They may also be taken out of
1706  * suspend by the host, using usb_resume_device().  It's also routine
1707  * to disconnect devices while they are suspended.
1708  *
1709  * Suspending OTG devices may trigger HNP, if that's been enabled
1710  * between a pair of dual-role devices.  That will change roles, such
1711  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1712  *
1713  * Returns 0 on success, else negative errno.
1714  */
1715 int usb_suspend_device(struct usb_device *udev, pm_message_t state)
1716 {
1717         int     port1, status;
1718
1719         port1 = locktree(udev);
1720         if (port1 < 0)
1721                 return port1;
1722
1723         status = __usb_suspend_device(udev, port1, state);
1724         usb_unlock_device(udev);
1725         return status;
1726 }
1727
1728 /*
1729  * hardware resume signaling is finished, either because of selective
1730  * resume (by host) or remote wakeup (by device) ... now see what changed
1731  * in the tree that's rooted at this device.
1732  */
1733 static int finish_port_resume(struct usb_device *udev)
1734 {
1735         int     status;
1736         u16     devstatus;
1737
1738         /* caller owns the udev device lock */
1739         dev_dbg(&udev->dev, "usb resume\n");
1740
1741         /* usb ch9 identifies four variants of SUSPENDED, based on what
1742          * state the device resumes to.  Linux currently won't see the
1743          * first two on the host side; they'd be inside hub_port_init()
1744          * during many timeouts, but khubd can't suspend until later.
1745          */
1746         usb_set_device_state(udev, udev->actconfig
1747                         ? USB_STATE_CONFIGURED
1748                         : USB_STATE_ADDRESS);
1749         udev->dev.power.power_state = PMSG_ON;
1750
1751         /* 10.5.4.5 says be sure devices in the tree are still there.
1752          * For now let's assume the device didn't go crazy on resume,
1753          * and device drivers will know about any resume quirks.
1754          */
1755         status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1756         if (status < 0)
1757                 dev_dbg(&udev->dev,
1758                         "gone after usb resume? status %d\n",
1759                         status);
1760         else if (udev->actconfig) {
1761                 unsigned        i;
1762
1763                 le16_to_cpus(&devstatus);
1764                 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
1765                         status = usb_control_msg(udev,
1766                                         usb_sndctrlpipe(udev, 0),
1767                                         USB_REQ_CLEAR_FEATURE,
1768                                                 USB_RECIP_DEVICE,
1769                                         USB_DEVICE_REMOTE_WAKEUP, 0,
1770                                         NULL, 0,
1771                                         USB_CTRL_SET_TIMEOUT);
1772                         if (status) {
1773                                 dev_dbg(&udev->dev, "disable remote "
1774                                         "wakeup, status %d\n", status);
1775                                 status = 0;
1776                         }
1777                 }
1778
1779                 /* resume interface drivers; if this is a hub, it
1780                  * resumes the child devices
1781                  */
1782                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1783                         struct usb_interface    *intf;
1784                         struct usb_driver       *driver;
1785
1786                         intf = udev->actconfig->interface[i];
1787                         if (intf->dev.power.power_state.event == PM_EVENT_ON)
1788                                 continue;
1789                         if (!intf->dev.driver) {
1790                                 /* FIXME maybe force to alt 0 */
1791                                 continue;
1792                         }
1793                         driver = to_usb_driver(intf->dev.driver);
1794
1795                         /* bus_rescan_devices() may rebind drivers */
1796                         if (!driver->resume)
1797                                 continue;
1798
1799                         /* can we do better than just logging errors? */
1800                         status = driver->resume(intf);
1801                         if (intf->dev.power.power_state.event != PM_EVENT_ON
1802                                         || status)
1803                                 dev_dbg(&intf->dev,
1804                                         "resume fail, state %d code %d\n",
1805                                         intf->dev.power.power_state.event, status);
1806                 }
1807                 status = 0;
1808
1809         } else if (udev->devnum <= 0) {
1810                 dev_dbg(&udev->dev, "bogus resume!\n");
1811                 status = -EINVAL;
1812         }
1813         return status;
1814 }
1815
1816 static int
1817 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1818 {
1819         int     status;
1820
1821         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1822
1823         /* see 7.1.7.7; affects power usage, but not budgeting */
1824         status = clear_port_feature(hub->hdev,
1825                         port1, USB_PORT_FEAT_SUSPEND);
1826         if (status) {
1827                 dev_dbg(hub->intfdev,
1828                         "can't resume port %d, status %d\n",
1829                         port1, status);
1830         } else {
1831                 u16             devstatus;
1832                 u16             portchange;
1833
1834                 /* drive resume for at least 20 msec */
1835                 if (udev)
1836                         dev_dbg(&udev->dev, "RESUME\n");
1837                 msleep(25);
1838
1839 #define LIVE_FLAGS      ( USB_PORT_STAT_POWER \
1840                         | USB_PORT_STAT_ENABLE \
1841                         | USB_PORT_STAT_CONNECTION)
1842
1843                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1844                  * stop resume signaling.  Then finish the resume
1845                  * sequence.
1846                  */
1847                 devstatus = portchange = 0;
1848                 status = hub_port_status(hub, port1,
1849                                 &devstatus, &portchange);
1850                 if (status < 0
1851                                 || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
1852                                 || (devstatus & USB_PORT_STAT_SUSPEND) != 0
1853                                 ) {
1854                         dev_dbg(hub->intfdev,
1855                                 "port %d status %04x.%04x after resume, %d\n",
1856                                 port1, portchange, devstatus, status);
1857                 } else {
1858                         /* TRSMRCY = 10 msec */
1859                         msleep(10);
1860                         if (udev)
1861                                 status = finish_port_resume(udev);
1862                 }
1863         }
1864         if (status < 0)
1865                 hub_port_logical_disconnect(hub, port1);
1866
1867         return status;
1868 }
1869
1870 static int hub_resume (struct usb_interface *intf);
1871
1872 /**
1873  * usb_resume_device - re-activate a suspended usb device
1874  * @udev: device to re-activate
1875  * Context: must be able to sleep; device not locked
1876  *
1877  * This will re-activate the suspended device, increasing power usage
1878  * while letting drivers communicate again with its endpoints.
1879  * USB resume explicitly guarantees that the power session between
1880  * the host and the device is the same as it was when the device
1881  * suspended.
1882  *
1883  * Returns 0 on success, else negative errno.
1884  */
1885 int usb_resume_device(struct usb_device *udev)
1886 {
1887         int     port1, status;
1888
1889         port1 = locktree(udev);
1890         if (port1 < 0)
1891                 return port1;
1892
1893         /* "global resume" of the HC-to-USB interface (root hub), or
1894          * selective resume of one hub-to-device port
1895          */
1896         if (!udev->parent) {
1897                 struct usb_bus  *bus = udev->bus;
1898                 if (bus && bus->op->hub_resume) {
1899                         status = bus->op->hub_resume (bus);
1900                 } else
1901                         status = -EOPNOTSUPP;
1902                 if (status == 0) {
1903                         dev_dbg(&udev->dev, "usb resume\n");
1904                         /* TRSMRCY = 10 msec */
1905                         msleep(10);
1906                         usb_set_device_state (udev, USB_STATE_CONFIGURED);
1907                         udev->dev.power.power_state = PMSG_ON;
1908                         status = hub_resume (udev
1909                                         ->actconfig->interface[0]);
1910                 }
1911         } else if (udev->state == USB_STATE_SUSPENDED) {
1912                 // NOTE this fails if parent is also suspended...
1913                 status = hub_port_resume(hdev_to_hub(udev->parent),
1914                                 port1, udev);
1915         } else {
1916                 status = 0;
1917         }
1918         if (status < 0) {
1919                 dev_dbg(&udev->dev, "can't resume, status %d\n",
1920                         status);
1921         }
1922
1923         usb_unlock_device(udev);
1924
1925         /* rebind drivers that had no suspend() */
1926         if (status == 0) {
1927                 usb_lock_all_devices();
1928                 bus_rescan_devices(&usb_bus_type);
1929                 usb_unlock_all_devices();
1930         }
1931         return status;
1932 }
1933
1934 static int remote_wakeup(struct usb_device *udev)
1935 {
1936         int     status = 0;
1937
1938         /* don't repeat RESUME sequence if this device
1939          * was already woken up by some other task
1940          */
1941         down(&udev->serialize);
1942         if (udev->state == USB_STATE_SUSPENDED) {
1943                 dev_dbg(&udev->dev, "RESUME (wakeup)\n");
1944                 /* TRSMRCY = 10 msec */
1945                 msleep(10);
1946                 status = finish_port_resume(udev);
1947         }
1948         up(&udev->serialize);
1949         return status;
1950 }
1951
1952 static int hub_suspend(struct usb_interface *intf, pm_message_t state)
1953 {
1954         struct usb_hub          *hub = usb_get_intfdata (intf);
1955         struct usb_device       *hdev = hub->hdev;
1956         unsigned                port1;
1957         int                     status;
1958
1959         /* stop khubd and related activity */
1960         hub_quiesce(hub);
1961
1962         /* then suspend every port */
1963         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1964                 struct usb_device       *udev;
1965
1966                 udev = hdev->children [port1-1];
1967                 if (!udev)
1968                         continue;
1969                 down(&udev->serialize);
1970                 status = __usb_suspend_device(udev, port1, state);
1971                 up(&udev->serialize);
1972                 if (status < 0)
1973                         dev_dbg(&intf->dev, "suspend port %d --> %d\n",
1974                                 port1, status);
1975         }
1976
1977         intf->dev.power.power_state = state;
1978         return 0;
1979 }
1980
1981 static int hub_resume(struct usb_interface *intf)
1982 {
1983         struct usb_device       *hdev = interface_to_usbdev(intf);
1984         struct usb_hub          *hub = usb_get_intfdata (intf);
1985         unsigned                port1;
1986         int                     status;
1987
1988         if (intf->dev.power.power_state.event == PM_EVENT_ON)
1989                 return 0;
1990
1991         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1992                 struct usb_device       *udev;
1993                 u16                     portstat, portchange;
1994
1995                 udev = hdev->children [port1-1];
1996                 status = hub_port_status(hub, port1, &portstat, &portchange);
1997                 if (status == 0) {
1998                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
1999                                 clear_port_feature(hdev, port1,
2000                                         USB_PORT_FEAT_C_SUSPEND);
2001                                 portchange &= ~USB_PORT_STAT_C_SUSPEND;
2002                         }
2003
2004                         /* let khubd handle disconnects etc */
2005                         if (portchange)
2006                                 continue;
2007                 }
2008
2009                 if (!udev || status < 0)
2010                         continue;
2011                 down (&udev->serialize);
2012                 if (portstat & USB_PORT_STAT_SUSPEND)
2013                         status = hub_port_resume(hub, port1, udev);
2014                 else {
2015                         status = finish_port_resume(udev);
2016                         if (status < 0) {
2017                                 dev_dbg(&intf->dev, "resume port %d --> %d\n",
2018                                         port1, status);
2019                                 hub_port_logical_disconnect(hub, port1);
2020                         }
2021                 }
2022                 up(&udev->serialize);
2023         }
2024         intf->dev.power.power_state = PMSG_ON;
2025
2026         hub->resume_root_hub = 0;
2027         hub_activate(hub);
2028         return 0;
2029 }
2030
2031 void usb_resume_root_hub(struct usb_device *hdev)
2032 {
2033         struct usb_hub *hub = hdev_to_hub(hdev);
2034
2035         hub->resume_root_hub = 1;
2036         kick_khubd(hub);
2037 }
2038
2039 #else   /* !CONFIG_USB_SUSPEND */
2040
2041 int usb_suspend_device(struct usb_device *udev, pm_message_t state)
2042 {
2043         return 0;
2044 }
2045
2046 int usb_resume_device(struct usb_device *udev)
2047 {
2048         return 0;
2049 }
2050
2051 #define hub_suspend             NULL
2052 #define hub_resume              NULL
2053 #define remote_wakeup(x)        0
2054
2055 #endif  /* CONFIG_USB_SUSPEND */
2056
2057 EXPORT_SYMBOL(usb_suspend_device);
2058 EXPORT_SYMBOL(usb_resume_device);
2059
2060
2061
2062 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2063  *
2064  * Between connect detection and reset signaling there must be a delay
2065  * of 100ms at least for debounce and power-settling.  The corresponding
2066  * timer shall restart whenever the downstream port detects a disconnect.
2067  *
2068  * Apparently there are some bluetooth and irda-dongles and a number of
2069  * low-speed devices for which this debounce period may last over a second.
2070  * Not covered by the spec - but easy to deal with.
2071  *
2072  * This implementation uses a 1500ms total debounce timeout; if the
2073  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
2074  * every 25ms for transient disconnects.  When the port status has been
2075  * unchanged for 100ms it returns the port status.
2076  */
2077
2078 #define HUB_DEBOUNCE_TIMEOUT    1500
2079 #define HUB_DEBOUNCE_STEP         25
2080 #define HUB_DEBOUNCE_STABLE      100
2081
2082 static int hub_port_debounce(struct usb_hub *hub, int port1)
2083 {
2084         int ret;
2085         int total_time, stable_time = 0;
2086         u16 portchange, portstatus;
2087         unsigned connection = 0xffff;
2088
2089         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2090                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2091                 if (ret < 0)
2092                         return ret;
2093
2094                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2095                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2096                         stable_time += HUB_DEBOUNCE_STEP;
2097                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2098                                 break;
2099                 } else {
2100                         stable_time = 0;
2101                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2102                 }
2103
2104                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2105                         clear_port_feature(hub->hdev, port1,
2106                                         USB_PORT_FEAT_C_CONNECTION);
2107                 }
2108
2109                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2110                         break;
2111                 msleep(HUB_DEBOUNCE_STEP);
2112         }
2113
2114         dev_dbg (hub->intfdev,
2115                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2116                 port1, total_time, stable_time, portstatus);
2117
2118         if (stable_time < HUB_DEBOUNCE_STABLE)
2119                 return -ETIMEDOUT;
2120         return portstatus;
2121 }
2122
2123 static void ep0_reinit(struct usb_device *udev)
2124 {
2125         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2126         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2127         udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2128 }
2129
2130 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2131 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2132
2133 static int hub_set_address(struct usb_device *udev)
2134 {
2135         int retval;
2136
2137         if (udev->devnum == 0)
2138                 return -EINVAL;
2139         if (udev->state == USB_STATE_ADDRESS)
2140                 return 0;
2141         if (udev->state != USB_STATE_DEFAULT)
2142                 return -EINVAL;
2143         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2144                 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2145                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2146         if (retval == 0) {
2147                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2148                 ep0_reinit(udev);
2149         }
2150         return retval;
2151 }
2152
2153 /* Reset device, (re)assign address, get device descriptor.
2154  * Device connection must be stable, no more debouncing needed.
2155  * Returns device in USB_STATE_ADDRESS, except on error.
2156  *
2157  * If this is called for an already-existing device (as part of
2158  * usb_reset_device), the caller must own the device lock.  For a
2159  * newly detected device that is not accessible through any global
2160  * pointers, it's not necessary to lock the device.
2161  */
2162 static int
2163 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2164                 int retry_counter)
2165 {
2166         static DECLARE_MUTEX(usb_address0_sem);
2167
2168         struct usb_device       *hdev = hub->hdev;
2169         int                     i, j, retval;
2170         unsigned                delay = HUB_SHORT_RESET_TIME;
2171         enum usb_device_speed   oldspeed = udev->speed;
2172
2173         /* root hub ports have a slightly longer reset period
2174          * (from USB 2.0 spec, section 7.1.7.5)
2175          */
2176         if (!hdev->parent) {
2177                 delay = HUB_ROOT_RESET_TIME;
2178                 if (port1 == hdev->bus->otg_port)
2179                         hdev->bus->b_hnp_enable = 0;
2180         }
2181
2182         /* Some low speed devices have problems with the quick delay, so */
2183         /*  be a bit pessimistic with those devices. RHbug #23670 */
2184         if (oldspeed == USB_SPEED_LOW)
2185                 delay = HUB_LONG_RESET_TIME;
2186
2187         down(&usb_address0_sem);
2188
2189         /* Reset the device; full speed may morph to high speed */
2190         retval = hub_port_reset(hub, port1, udev, delay);
2191         if (retval < 0)         /* error or disconnect */
2192                 goto fail;
2193                                 /* success, speed is known */
2194         retval = -ENODEV;
2195
2196         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2197                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2198                 goto fail;
2199         }
2200         oldspeed = udev->speed;
2201
2202         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2203          * it's fixed size except for full speed devices.
2204          */
2205         switch (udev->speed) {
2206         case USB_SPEED_HIGH:            /* fixed at 64 */
2207                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2208                 break;
2209         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2210                 /* to determine the ep0 maxpacket size, try to read
2211                  * the device descriptor to get bMaxPacketSize0 and
2212                  * then correct our initial guess.
2213                  */
2214                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2215                 break;
2216         case USB_SPEED_LOW:             /* fixed at 8 */
2217                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2218                 break;
2219         default:
2220                 goto fail;
2221         }
2222
2223         dev_info (&udev->dev,
2224                         "%s %s speed USB device using %s and address %d\n",
2225                         (udev->config) ? "reset" : "new",
2226                         ({ char *speed; switch (udev->speed) {
2227                         case USB_SPEED_LOW:     speed = "low";  break;
2228                         case USB_SPEED_FULL:    speed = "full"; break;
2229                         case USB_SPEED_HIGH:    speed = "high"; break;
2230                         default:                speed = "?";    break;
2231                         }; speed;}),
2232                         udev->bus->controller->driver->name,
2233                         udev->devnum);
2234
2235         /* Set up TT records, if needed  */
2236         if (hdev->tt) {
2237                 udev->tt = hdev->tt;
2238                 udev->ttport = hdev->ttport;
2239         } else if (udev->speed != USB_SPEED_HIGH
2240                         && hdev->speed == USB_SPEED_HIGH) {
2241                 udev->tt = &hub->tt;
2242                 udev->ttport = port1;
2243         }
2244
2245         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2246          * Because device hardware and firmware is sometimes buggy in
2247          * this area, and this is how Linux has done it for ages.
2248          * Change it cautiously.
2249          *
2250          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2251          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2252          * so it may help with some non-standards-compliant devices.
2253          * Otherwise we start with SET_ADDRESS and then try to read the
2254          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2255          * value.
2256          */
2257         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2258                 if (USE_NEW_SCHEME(retry_counter)) {
2259                         struct usb_device_descriptor *buf;
2260                         int r = 0;
2261
2262 #define GET_DESCRIPTOR_BUFSIZE  64
2263                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2264                         if (!buf) {
2265                                 retval = -ENOMEM;
2266                                 continue;
2267                         }
2268
2269                         /* Use a short timeout the first time through,
2270                          * so that recalcitrant full-speed devices with
2271                          * 8- or 16-byte ep0-maxpackets won't slow things
2272                          * down tremendously by NAKing the unexpectedly
2273                          * early status stage.  Also, retry on all errors;
2274                          * some devices are flakey.
2275                          */
2276                         for (j = 0; j < 3; ++j) {
2277                                 buf->bMaxPacketSize0 = 0;
2278                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2279                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2280                                         USB_DT_DEVICE << 8, 0,
2281                                         buf, GET_DESCRIPTOR_BUFSIZE,
2282                                         (i ? USB_CTRL_GET_TIMEOUT : 1000));
2283                                 switch (buf->bMaxPacketSize0) {
2284                                 case 8: case 16: case 32: case 64:
2285                                         if (buf->bDescriptorType ==
2286                                                         USB_DT_DEVICE) {
2287                                                 r = 0;
2288                                                 break;
2289                                         }
2290                                         /* FALL THROUGH */
2291                                 default:
2292                                         if (r == 0)
2293                                                 r = -EPROTO;
2294                                         break;
2295                                 }
2296                                 if (r == 0)
2297                                         break;
2298                         }
2299                         udev->descriptor.bMaxPacketSize0 =
2300                                         buf->bMaxPacketSize0;
2301                         kfree(buf);
2302
2303                         retval = hub_port_reset(hub, port1, udev, delay);
2304                         if (retval < 0)         /* error or disconnect */
2305                                 goto fail;
2306                         if (oldspeed != udev->speed) {
2307                                 dev_dbg(&udev->dev,
2308                                         "device reset changed speed!\n");
2309                                 retval = -ENODEV;
2310                                 goto fail;
2311                         }
2312                         if (r) {
2313                                 dev_err(&udev->dev, "device descriptor "
2314                                                 "read/%s, error %d\n",
2315                                                 "64", r);
2316                                 retval = -EMSGSIZE;
2317                                 continue;
2318                         }
2319 #undef GET_DESCRIPTOR_BUFSIZE
2320                 }
2321
2322                 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2323                         retval = hub_set_address(udev);
2324                         if (retval >= 0)
2325                                 break;
2326                         msleep(200);
2327                 }
2328                 if (retval < 0) {
2329                         dev_err(&udev->dev,
2330                                 "device not accepting address %d, error %d\n",
2331                                 udev->devnum, retval);
2332                         goto fail;
2333                 }
2334
2335                 /* cope with hardware quirkiness:
2336                  *  - let SET_ADDRESS settle, some device hardware wants it
2337                  *  - read ep0 maxpacket even for high and low speed,
2338                  */
2339                 msleep(10);
2340                 if (USE_NEW_SCHEME(retry_counter))
2341                         break;
2342
2343                 retval = usb_get_device_descriptor(udev, 8);
2344                 if (retval < 8) {
2345                         dev_err(&udev->dev, "device descriptor "
2346                                         "read/%s, error %d\n",
2347                                         "8", retval);
2348                         if (retval >= 0)
2349                                 retval = -EMSGSIZE;
2350                 } else {
2351                         retval = 0;
2352                         break;
2353                 }
2354         }
2355         if (retval)
2356                 goto fail;
2357
2358         i = udev->descriptor.bMaxPacketSize0;
2359         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2360                 if (udev->speed != USB_SPEED_FULL ||
2361                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2362                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2363                         retval = -EMSGSIZE;
2364                         goto fail;
2365                 }
2366                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2367                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2368                 ep0_reinit(udev);
2369         }
2370
2371         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2372         if (retval < (signed)sizeof(udev->descriptor)) {
2373                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2374                         "all", retval);
2375                 if (retval >= 0)
2376                         retval = -ENOMSG;
2377                 goto fail;
2378         }
2379
2380         retval = 0;
2381
2382 fail:
2383         if (retval)
2384                 hub_port_disable(hub, port1, 0);
2385         up(&usb_address0_sem);
2386         return retval;
2387 }
2388
2389 static void
2390 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2391 {
2392         struct usb_qualifier_descriptor *qual;
2393         int                             status;
2394
2395         qual = kmalloc (sizeof *qual, SLAB_KERNEL);
2396         if (qual == NULL)
2397                 return;
2398
2399         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2400                         qual, sizeof *qual);
2401         if (status == sizeof *qual) {
2402                 dev_info(&udev->dev, "not running at top speed; "
2403                         "connect to a high speed hub\n");
2404                 /* hub LEDs are probably harder to miss than syslog */
2405                 if (hub->has_indicators) {
2406                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2407                         schedule_work (&hub->leds);
2408                 }
2409         }
2410         kfree(qual);
2411 }
2412
2413 static unsigned
2414 hub_power_remaining (struct usb_hub *hub)
2415 {
2416         struct usb_device *hdev = hub->hdev;
2417         int remaining;
2418         unsigned i;
2419
2420         remaining = hub->power_budget;
2421         if (!remaining)         /* self-powered */
2422                 return 0;
2423
2424         for (i = 0; i < hdev->maxchild; i++) {
2425                 struct usb_device       *udev = hdev->children[i];
2426                 int                     delta, ceiling;
2427
2428                 if (!udev)
2429                         continue;
2430
2431                 /* 100mA per-port ceiling, or 8mA for OTG ports */
2432                 if (i != (udev->bus->otg_port - 1) || hdev->parent)
2433                         ceiling = 50;
2434                 else
2435                         ceiling = 4;
2436
2437                 if (udev->actconfig)
2438                         delta = udev->actconfig->desc.bMaxPower;
2439                 else
2440                         delta = ceiling;
2441                 // dev_dbg(&udev->dev, "budgeted %dmA\n", 2 * delta);
2442                 if (delta > ceiling)
2443                         dev_warn(&udev->dev, "%dmA over %dmA budget!\n",
2444                                 2 * (delta - ceiling), 2 * ceiling);
2445                 remaining -= delta;
2446         }
2447         if (remaining < 0) {
2448                 dev_warn(hub->intfdev,
2449                         "%dmA over power budget!\n",
2450                         -2 * remaining);
2451                 remaining = 0;
2452         }
2453         return remaining;
2454 }
2455
2456 /* Handle physical or logical connection change events.
2457  * This routine is called when:
2458  *      a port connection-change occurs;
2459  *      a port enable-change occurs (often caused by EMI);
2460  *      usb_reset_device() encounters changed descriptors (as from
2461  *              a firmware download)
2462  * caller already locked the hub
2463  */
2464 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2465                                         u16 portstatus, u16 portchange)
2466 {
2467         struct usb_device *hdev = hub->hdev;
2468         struct device *hub_dev = hub->intfdev;
2469         int status, i;
2470
2471         dev_dbg (hub_dev,
2472                 "port %d, status %04x, change %04x, %s\n",
2473                 port1, portstatus, portchange, portspeed (portstatus));
2474
2475         if (hub->has_indicators) {
2476                 set_port_led(hub, port1, HUB_LED_AUTO);
2477                 hub->indicator[port1-1] = INDICATOR_AUTO;
2478         }
2479
2480         /* Disconnect any existing devices under this port */
2481         if (hdev->children[port1-1])
2482                 usb_disconnect(&hdev->children[port1-1]);
2483         clear_bit(port1, hub->change_bits);
2484
2485 #ifdef  CONFIG_USB_OTG
2486         /* during HNP, don't repeat the debounce */
2487         if (hdev->bus->is_b_host)
2488                 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2489 #endif
2490
2491         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2492                 status = hub_port_debounce(hub, port1);
2493                 if (status < 0) {
2494                         dev_err (hub_dev,
2495                                 "connect-debounce failed, port %d disabled\n",
2496                                 port1);
2497                         goto done;
2498                 }
2499                 portstatus = status;
2500         }
2501
2502         /* Return now if nothing is connected */
2503         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2504
2505                 /* maybe switch power back on (e.g. root hub was reset) */
2506                 if ((hub->descriptor->wHubCharacteristics
2507                                         & HUB_CHAR_LPSM) < 2
2508                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2509                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2510
2511                 if (portstatus & USB_PORT_STAT_ENABLE)
2512                         goto done;
2513                 return;
2514         }
2515
2516 #ifdef  CONFIG_USB_SUSPEND
2517         /* If something is connected, but the port is suspended, wake it up. */
2518         if (portstatus & USB_PORT_STAT_SUSPEND) {
2519                 status = hub_port_resume(hub, port1, NULL);
2520                 if (status < 0) {
2521                         dev_dbg(hub_dev,
2522                                 "can't clear suspend on port %d; %d\n",
2523                                 port1, status);
2524                         goto done;
2525                 }
2526         }
2527 #endif
2528
2529         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2530                 struct usb_device *udev;
2531
2532                 /* reallocate for each attempt, since references
2533                  * to the previous one can escape in various ways
2534                  */
2535                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2536                 if (!udev) {
2537                         dev_err (hub_dev,
2538                                 "couldn't allocate port %d usb_device\n",
2539                                 port1);
2540                         goto done;
2541                 }
2542
2543                 usb_set_device_state(udev, USB_STATE_POWERED);
2544                 udev->speed = USB_SPEED_UNKNOWN;
2545
2546                 /* set the address */
2547                 choose_address(udev);
2548                 if (udev->devnum <= 0) {
2549                         status = -ENOTCONN;     /* Don't retry */
2550                         goto loop;
2551                 }
2552
2553                 /* reset and get descriptor */
2554                 status = hub_port_init(hub, udev, port1, i);
2555                 if (status < 0)
2556                         goto loop;
2557
2558                 /* consecutive bus-powered hubs aren't reliable; they can
2559                  * violate the voltage drop budget.  if the new child has
2560                  * a "powered" LED, users should notice we didn't enable it
2561                  * (without reading syslog), even without per-port LEDs
2562                  * on the parent.
2563                  */
2564                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2565                                 && hub->power_budget) {
2566                         u16     devstat;
2567
2568                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2569                                         &devstat);
2570                         if (status < 0) {
2571                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2572                                 goto loop_disable;
2573                         }
2574                         cpu_to_le16s(&devstat);
2575                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2576                                 dev_err(&udev->dev,
2577                                         "can't connect bus-powered hub "
2578                                         "to this port\n");
2579                                 if (hub->has_indicators) {
2580                                         hub->indicator[port1-1] =
2581                                                 INDICATOR_AMBER_BLINK;
2582                                         schedule_work (&hub->leds);
2583                                 }
2584                                 status = -ENOTCONN;     /* Don't retry */
2585                                 goto loop_disable;
2586                         }
2587                 }
2588
2589                 /* check for devices running slower than they could */
2590                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2591                                 && udev->speed == USB_SPEED_FULL
2592                                 && highspeed_hubs != 0)
2593                         check_highspeed (hub, udev, port1);
2594
2595                 /* Store the parent's children[] pointer.  At this point
2596                  * udev becomes globally accessible, although presumably
2597                  * no one will look at it until hdev is unlocked.
2598                  */
2599                 down (&udev->serialize);
2600                 status = 0;
2601
2602                 /* We mustn't add new devices if the parent hub has
2603                  * been disconnected; we would race with the
2604                  * recursively_mark_NOTATTACHED() routine.
2605                  */
2606                 spin_lock_irq(&device_state_lock);
2607                 if (hdev->state == USB_STATE_NOTATTACHED)
2608                         status = -ENOTCONN;
2609                 else
2610                         hdev->children[port1-1] = udev;
2611                 spin_unlock_irq(&device_state_lock);
2612
2613                 /* Run it through the hoops (find a driver, etc) */
2614                 if (!status) {
2615                         status = usb_new_device(udev);
2616                         if (status) {
2617                                 spin_lock_irq(&device_state_lock);
2618                                 hdev->children[port1-1] = NULL;
2619                                 spin_unlock_irq(&device_state_lock);
2620                         }
2621                 }
2622
2623                 up (&udev->serialize);
2624                 if (status)
2625                         goto loop_disable;
2626
2627                 status = hub_power_remaining(hub);
2628                 if (status)
2629                         dev_dbg(hub_dev,
2630                                 "%dmA power budget left\n",
2631                                 2 * status);
2632
2633                 return;
2634
2635 loop_disable:
2636                 hub_port_disable(hub, port1, 1);
2637 loop:
2638                 ep0_reinit(udev);
2639                 release_address(udev);
2640                 usb_put_dev(udev);
2641                 if (status == -ENOTCONN)
2642                         break;
2643         }
2644
2645 done:
2646         hub_port_disable(hub, port1, 1);
2647 }
2648
2649 static void hub_events(void)
2650 {
2651         struct list_head *tmp;
2652         struct usb_device *hdev;
2653         struct usb_interface *intf;
2654         struct usb_hub *hub;
2655         struct device *hub_dev;
2656         u16 hubstatus;
2657         u16 hubchange;
2658         u16 portstatus;
2659         u16 portchange;
2660         int i, ret;
2661         int connect_change;
2662
2663         /*
2664          *  We restart the list every time to avoid a deadlock with
2665          * deleting hubs downstream from this one. This should be
2666          * safe since we delete the hub from the event list.
2667          * Not the most efficient, but avoids deadlocks.
2668          */
2669         while (1) {
2670
2671                 /* Grab the first entry at the beginning of the list */
2672                 spin_lock_irq(&hub_event_lock);
2673                 if (list_empty(&hub_event_list)) {
2674                         spin_unlock_irq(&hub_event_lock);
2675                         break;
2676                 }
2677
2678                 tmp = hub_event_list.next;
2679                 list_del_init(tmp);
2680
2681                 hub = list_entry(tmp, struct usb_hub, event_list);
2682                 hdev = hub->hdev;
2683                 intf = to_usb_interface(hub->intfdev);
2684                 hub_dev = &intf->dev;
2685
2686                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
2687                                 hdev->state, hub->descriptor
2688                                         ? hub->descriptor->bNbrPorts
2689                                         : 0,
2690                                 /* NOTE: expects max 15 ports... */
2691                                 (u16) hub->change_bits[0],
2692                                 (u16) hub->event_bits[0]);
2693
2694                 usb_get_intf(intf);
2695                 i = hub->resume_root_hub;
2696                 spin_unlock_irq(&hub_event_lock);
2697
2698                 /* Is this is a root hub wanting to be resumed? */
2699                 if (i)
2700                         usb_resume_device(hdev);
2701
2702                 /* Lock the device, then check to see if we were
2703                  * disconnected while waiting for the lock to succeed. */
2704                 if (locktree(hdev) < 0) {
2705                         usb_put_intf(intf);
2706                         continue;
2707                 }
2708                 if (hub != usb_get_intfdata(intf))
2709                         goto loop;
2710
2711                 /* If the hub has died, clean up after it */
2712                 if (hdev->state == USB_STATE_NOTATTACHED) {
2713                         hub_pre_reset(hub);
2714                         goto loop;
2715                 }
2716
2717                 /* If this is an inactive or suspended hub, do nothing */
2718                 if (hub->quiescing)
2719                         goto loop;
2720
2721                 if (hub->error) {
2722                         dev_dbg (hub_dev, "resetting for error %d\n",
2723                                 hub->error);
2724
2725                         ret = usb_reset_device(hdev);
2726                         if (ret) {
2727                                 dev_dbg (hub_dev,
2728                                         "error resetting hub: %d\n", ret);
2729                                 goto loop;
2730                         }
2731
2732                         hub->nerrors = 0;
2733                         hub->error = 0;
2734                 }
2735
2736                 /* deal with port status changes */
2737                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2738                         if (test_bit(i, hub->busy_bits))
2739                                 continue;
2740                         connect_change = test_bit(i, hub->change_bits);
2741                         if (!test_and_clear_bit(i, hub->event_bits) &&
2742                                         !connect_change && !hub->activating)
2743                                 continue;
2744
2745                         ret = hub_port_status(hub, i,
2746                                         &portstatus, &portchange);
2747                         if (ret < 0)
2748                                 continue;
2749
2750                         if (hub->activating && !hdev->children[i-1] &&
2751                                         (portstatus &
2752                                                 USB_PORT_STAT_CONNECTION))
2753                                 connect_change = 1;
2754
2755                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2756                                 clear_port_feature(hdev, i,
2757                                         USB_PORT_FEAT_C_CONNECTION);
2758                                 connect_change = 1;
2759                         }
2760
2761                         if (portchange & USB_PORT_STAT_C_ENABLE) {
2762                                 if (!connect_change)
2763                                         dev_dbg (hub_dev,
2764                                                 "port %d enable change, "
2765                                                 "status %08x\n",
2766                                                 i, portstatus);
2767                                 clear_port_feature(hdev, i,
2768                                         USB_PORT_FEAT_C_ENABLE);
2769
2770                                 /*
2771                                  * EM interference sometimes causes badly
2772                                  * shielded USB devices to be shutdown by
2773                                  * the hub, this hack enables them again.
2774                                  * Works at least with mouse driver.
2775                                  */
2776                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
2777                                     && !connect_change
2778                                     && hdev->children[i-1]) {
2779                                         dev_err (hub_dev,
2780                                             "port %i "
2781                                             "disabled by hub (EMI?), "
2782                                             "re-enabling...\n",
2783                                                 i);
2784                                         connect_change = 1;
2785                                 }
2786                         }
2787
2788                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2789                                 clear_port_feature(hdev, i,
2790                                         USB_PORT_FEAT_C_SUSPEND);
2791                                 if (hdev->children[i-1]) {
2792                                         ret = remote_wakeup(hdev->
2793                                                         children[i-1]);
2794                                         if (ret < 0)
2795                                                 connect_change = 1;
2796                                 } else {
2797                                         ret = -ENODEV;
2798                                         hub_port_disable(hub, i, 1);
2799                                 }
2800                                 dev_dbg (hub_dev,
2801                                         "resume on port %d, status %d\n",
2802                                         i, ret);
2803                         }
2804
2805                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2806                                 dev_err (hub_dev,
2807                                         "over-current change on port %d\n",
2808                                         i);
2809                                 clear_port_feature(hdev, i,
2810                                         USB_PORT_FEAT_C_OVER_CURRENT);
2811                                 hub_power_on(hub);
2812                         }
2813
2814                         if (portchange & USB_PORT_STAT_C_RESET) {
2815                                 dev_dbg (hub_dev,
2816                                         "reset change on port %d\n",
2817                                         i);
2818                                 clear_port_feature(hdev, i,
2819                                         USB_PORT_FEAT_C_RESET);
2820                         }
2821
2822                         if (connect_change)
2823                                 hub_port_connect_change(hub, i,
2824                                                 portstatus, portchange);
2825                 } /* end for i */
2826
2827                 /* deal with hub status changes */
2828                 if (test_and_clear_bit(0, hub->event_bits) == 0)
2829                         ;       /* do nothing */
2830                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2831                         dev_err (hub_dev, "get_hub_status failed\n");
2832                 else {
2833                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2834                                 dev_dbg (hub_dev, "power change\n");
2835                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2836                         }
2837                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
2838                                 dev_dbg (hub_dev, "overcurrent change\n");
2839                                 msleep(500);    /* Cool down */
2840                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2841                                 hub_power_on(hub);
2842                         }
2843                 }
2844
2845                 hub->activating = 0;
2846
2847                 /* If this is a root hub, tell the HCD it's okay to
2848                  * re-enable port-change interrupts now. */
2849                 if (!hdev->parent)
2850                         usb_enable_root_hub_irq(hdev->bus);
2851
2852 loop:
2853                 usb_unlock_device(hdev);
2854                 usb_put_intf(intf);
2855
2856         } /* end while (1) */
2857 }
2858
2859 static int hub_thread(void *__unused)
2860 {
2861         do {
2862                 hub_events();
2863                 wait_event_interruptible(khubd_wait,
2864                                 !list_empty(&hub_event_list) ||
2865                                 kthread_should_stop());
2866                 try_to_freeze();
2867         } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2868
2869         pr_debug("%s: khubd exiting\n", usbcore_name);
2870         return 0;
2871 }
2872
2873 static struct usb_device_id hub_id_table [] = {
2874     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2875       .bDeviceClass = USB_CLASS_HUB},
2876     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2877       .bInterfaceClass = USB_CLASS_HUB},
2878     { }                                         /* Terminating entry */
2879 };
2880
2881 MODULE_DEVICE_TABLE (usb, hub_id_table);
2882
2883 static struct usb_driver hub_driver = {
2884         .owner =        THIS_MODULE,
2885         .name =         "hub",
2886         .probe =        hub_probe,
2887         .disconnect =   hub_disconnect,
2888         .suspend =      hub_suspend,
2889         .resume =       hub_resume,
2890         .ioctl =        hub_ioctl,
2891         .id_table =     hub_id_table,
2892 };
2893
2894 int usb_hub_init(void)
2895 {
2896         if (usb_register(&hub_driver) < 0) {
2897                 printk(KERN_ERR "%s: can't register hub driver\n",
2898                         usbcore_name);
2899                 return -1;
2900         }
2901
2902         khubd_task = kthread_run(hub_thread, NULL, "khubd");
2903         if (!IS_ERR(khubd_task))
2904                 return 0;
2905
2906         /* Fall through if kernel_thread failed */
2907         usb_deregister(&hub_driver);
2908         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2909
2910         return -1;
2911 }
2912
2913 void usb_hub_cleanup(void)
2914 {
2915         kthread_stop(khubd_task);
2916
2917         /*
2918          * Hub resources are freed for us by usb_deregister. It calls
2919          * usb_driver_purge on every device which in turn calls that
2920          * devices disconnect function if it is using this driver.
2921          * The hub_disconnect function takes care of releasing the
2922          * individual hub resources. -greg
2923          */
2924         usb_deregister(&hub_driver);
2925 } /* usb_hub_cleanup() */
2926
2927 static int config_descriptors_changed(struct usb_device *udev)
2928 {
2929         unsigned                        index;
2930         unsigned                        len = 0;
2931         struct usb_config_descriptor    *buf;
2932
2933         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2934                 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2935                         len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2936         }
2937         buf = kmalloc (len, SLAB_KERNEL);
2938         if (buf == NULL) {
2939                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2940                 /* assume the worst */
2941                 return 1;
2942         }
2943         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2944                 int length;
2945                 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2946
2947                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2948                                 old_length);
2949                 if (length < old_length) {
2950                         dev_dbg(&udev->dev, "config index %d, error %d\n",
2951                                         index, length);
2952                         break;
2953                 }
2954                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2955                                 != 0) {
2956                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2957                                 index, buf->bConfigurationValue);
2958                         break;
2959                 }
2960         }
2961         kfree(buf);
2962         return index != udev->descriptor.bNumConfigurations;
2963 }
2964
2965 /**
2966  * usb_reset_device - perform a USB port reset to reinitialize a device
2967  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2968  *
2969  * WARNING - don't reset any device unless drivers for all of its
2970  * interfaces are expecting that reset!  Maybe some driver->reset()
2971  * method should eventually help ensure sufficient cooperation.
2972  *
2973  * Do a port reset, reassign the device's address, and establish its
2974  * former operating configuration.  If the reset fails, or the device's
2975  * descriptors change from their values before the reset, or the original
2976  * configuration and altsettings cannot be restored, a flag will be set
2977  * telling khubd to pretend the device has been disconnected and then
2978  * re-connected.  All drivers will be unbound, and the device will be
2979  * re-enumerated and probed all over again.
2980  *
2981  * Returns 0 if the reset succeeded, -ENODEV if the device has been
2982  * flagged for logical disconnection, or some other negative error code
2983  * if the reset wasn't even attempted.
2984  *
2985  * The caller must own the device lock.  For example, it's safe to use
2986  * this from a driver probe() routine after downloading new firmware.
2987  * For calls that might not occur during probe(), drivers should lock
2988  * the device using usb_lock_device_for_reset().
2989  */
2990 int usb_reset_device(struct usb_device *udev)
2991 {
2992         struct usb_device               *parent_hdev = udev->parent;
2993         struct usb_hub                  *parent_hub;
2994         struct usb_device_descriptor    descriptor = udev->descriptor;
2995         struct usb_hub                  *hub = NULL;
2996         int                             i, ret = 0, port1 = -1;
2997
2998         if (udev->state == USB_STATE_NOTATTACHED ||
2999                         udev->state == USB_STATE_SUSPENDED) {
3000                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3001                                 udev->state);
3002                 return -EINVAL;
3003         }
3004
3005         if (!parent_hdev) {
3006                 /* this requires hcd-specific logic; see OHCI hc_restart() */
3007                 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
3008                 return -EISDIR;
3009         }
3010
3011         for (i = 0; i < parent_hdev->maxchild; i++)
3012                 if (parent_hdev->children[i] == udev) {
3013                         port1 = i + 1;
3014                         break;
3015                 }
3016
3017         if (port1 < 0) {
3018                 /* If this ever happens, it's very bad */
3019                 dev_err(&udev->dev, "Can't locate device's port!\n");
3020                 return -ENOENT;
3021         }
3022         parent_hub = hdev_to_hub(parent_hdev);
3023
3024         /* If we're resetting an active hub, take some special actions */
3025         if (udev->actconfig &&
3026                         udev->actconfig->interface[0]->dev.driver ==
3027                                 &hub_driver.driver &&
3028                         (hub = hdev_to_hub(udev)) != NULL) {
3029                 hub_pre_reset(hub);
3030         }
3031
3032         set_bit(port1, parent_hub->busy_bits);
3033         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
3034
3035                 /* ep0 maxpacket size may change; let the HCD know about it.
3036                  * Other endpoints will be handled by re-enumeration. */
3037                 ep0_reinit(udev);
3038                 ret = hub_port_init(parent_hub, udev, port1, i);
3039                 if (ret >= 0)
3040                         break;
3041         }
3042         clear_bit(port1, parent_hub->busy_bits);
3043         if (ret < 0)
3044                 goto re_enumerate;
3045
3046         /* Device might have changed firmware (DFU or similar) */
3047         if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
3048                         || config_descriptors_changed (udev)) {
3049                 dev_info(&udev->dev, "device firmware changed\n");
3050                 udev->descriptor = descriptor;  /* for disconnect() calls */
3051                 goto re_enumerate;
3052         }
3053
3054         if (!udev->actconfig)
3055                 goto done;
3056
3057         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3058                         USB_REQ_SET_CONFIGURATION, 0,
3059                         udev->actconfig->desc.bConfigurationValue, 0,
3060                         NULL, 0, USB_CTRL_SET_TIMEOUT);
3061         if (ret < 0) {
3062                 dev_err(&udev->dev,
3063                         "can't restore configuration #%d (error=%d)\n",
3064                         udev->actconfig->desc.bConfigurationValue, ret);
3065                 goto re_enumerate;
3066         }
3067         usb_set_device_state(udev, USB_STATE_CONFIGURED);
3068
3069         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3070                 struct usb_interface *intf = udev->actconfig->interface[i];
3071                 struct usb_interface_descriptor *desc;
3072
3073                 /* set_interface resets host side toggle even
3074                  * for altsetting zero.  the interface may have no driver.
3075                  */
3076                 desc = &intf->cur_altsetting->desc;
3077                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3078                         desc->bAlternateSetting);
3079                 if (ret < 0) {
3080                         dev_err(&udev->dev, "failed to restore interface %d "
3081                                 "altsetting %d (error=%d)\n",
3082                                 desc->bInterfaceNumber,
3083                                 desc->bAlternateSetting,
3084                                 ret);
3085                         goto re_enumerate;
3086                 }
3087         }
3088
3089 done:
3090         if (hub)
3091                 hub_post_reset(hub);
3092         return 0;
3093
3094 re_enumerate:
3095         hub_port_logical_disconnect(parent_hub, port1);
3096         return -ENODEV;
3097 }