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         unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
 439         u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
 440
 441         /* if hub supports power switching, enable power on each port */
 442         if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2) {
 443                 dev_dbg(hub->intfdev, "enabling power on all ports\n");
 444                 for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
 445                         set_port_feature(hub->hdev, port1,
 446                                         USB_PORT_FEAT_POWER);
 447         }
 448
 449         /* Wait at least 100 msec for power to become stable */
 450         msleep(max(pgood_delay, (unsigned) 100));
 451 }
 452
 453 static inline void __hub_quiesce(struct usb_hub *hub)
 454 {
 455         /* (nonblocking) khubd and related activity won't re-trigger */
 456         hub->quiescing = 1;
 457         hub->activating = 0;
 458         hub->resume_root_hub = 0;
 459 }
 460
 461 static void hub_quiesce(struct usb_hub *hub)
 462 {
 463         /* (blocking) stop khubd and related activity */
 464         __hub_quiesce(hub);
 465         usb_kill_urb(hub->urb);
 466         if (hub->has_indicators)
 467                 cancel_delayed_work(&hub->leds);
 468         if (hub->has_indicators || hub->tt.hub)
 469                 flush_scheduled_work();
 470 }
 471
 472 static void hub_activate(struct usb_hub *hub)
 473 {
 474         int     status;
 475
 476         hub->quiescing = 0;
 477         hub->activating = 1;
 478         hub->resume_root_hub = 0;
 479         status = usb_submit_urb(hub->urb, GFP_NOIO);
 480         if (status < 0)
 481                 dev_err(hub->intfdev, "activate --> %d\n", status);
 482         if (hub->has_indicators && blinkenlights)
 483                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 484
 485         /* scan all ports ASAP */
 486         kick_khubd(hub);
 487 }
 488
 489 static int hub_hub_status(struct usb_hub *hub,
 490                 u16 *status, u16 *change)
 491 {
 492         int ret;
 493
 494         ret = get_hub_status(hub->hdev, &hub->status->hub);
 495         if (ret < 0)
 496                 dev_err (hub->intfdev,
 497                         "%s failed (err = %d)\n", __FUNCTION__, ret);
 498         else {
 499                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
 500                 *change = le16_to_cpu(hub->status->hub.wHubChange);
 501                 ret = 0;
 502         }
 503         return ret;
 504 }
 505
 506 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
 507 {
 508         struct usb_device *hdev = hub->hdev;
 509         int ret;
 510
 511         if (hdev->children[port1-1] && set_state) {
 512                 usb_set_device_state(hdev->children[port1-1],
 513                                 USB_STATE_NOTATTACHED);
 514         }
 515         ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
 516         if (ret)
 517                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
 518                         port1, ret);
 519
 520         return ret;
 521 }
 522
 523 static int hub_configure(struct usb_hub *hub,
 524         struct usb_endpoint_descriptor *endpoint)
 525 {
 526         struct usb_device *hdev = hub->hdev;
 527         struct device *hub_dev = hub->intfdev;
 528         u16 hubstatus, hubchange;
 529         u16 wHubCharacteristics;
 530         unsigned int pipe;
 531         int maxp, ret;
 532         char *message;
 533
 534         hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
 535                         &hub->buffer_dma);
 536         if (!hub->buffer) {
 537                 message = "can't allocate hub irq buffer";
 538                 ret = -ENOMEM;
 539                 goto fail;
 540         }
 541
 542         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
 543         if (!hub->status) {
 544                 message = "can't kmalloc hub status buffer";
 545                 ret = -ENOMEM;
 546                 goto fail;
 547         }
 548
 549         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
 550         if (!hub->descriptor) {
 551                 message = "can't kmalloc hub descriptor";
 552                 ret = -ENOMEM;
 553                 goto fail;
 554         }
 555
 556         /* Request the entire hub descriptor.
 557          * hub->descriptor can handle USB_MAXCHILDREN ports,
 558          * but the hub can/will return fewer bytes here.
 559          */
 560         ret = get_hub_descriptor(hdev, hub->descriptor,
 561                         sizeof(*hub->descriptor));
 562         if (ret < 0) {
 563                 message = "can't read hub descriptor";
 564                 goto fail;
 565         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
 566                 message = "hub has too many ports!";
 567                 ret = -ENODEV;
 568                 goto fail;
 569         }
 570
 571         hdev->maxchild = hub->descriptor->bNbrPorts;
 572         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
 573                 (hdev->maxchild == 1) ? "" : "s");
 574
 575         wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
 576
 577         if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
 578                 int     i;
 579                 char    portstr [USB_MAXCHILDREN + 1];
 580
 581                 for (i = 0; i < hdev->maxchild; i++)
 582                         portstr[i] = hub->descriptor->DeviceRemovable
 583                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
 584                                 ? 'F' : 'R';
 585                 portstr[hdev->maxchild] = 0;
 586                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
 587         } else
 588                 dev_dbg(hub_dev, "standalone hub\n");
 589
 590         switch (wHubCharacteristics & HUB_CHAR_LPSM) {
 591                 case 0x00:
 592                         dev_dbg(hub_dev, "ganged power switching\n");
 593                         break;
 594                 case 0x01:
 595                         dev_dbg(hub_dev, "individual port power switching\n");
 596                         break;
 597                 case 0x02:
 598                 case 0x03:
 599                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
 600                         break;
 601         }
 602
 603         switch (wHubCharacteristics & HUB_CHAR_OCPM) {
 604                 case 0x00:
 605                         dev_dbg(hub_dev, "global over-current protection\n");
 606                         break;
 607                 case 0x08:
 608                         dev_dbg(hub_dev, "individual port over-current protection\n");
 609                         break;
 610                 case 0x10:
 611                 case 0x18:
 612                         dev_dbg(hub_dev, "no over-current protection\n");
 613                         break;
 614         }
 615
 616         spin_lock_init (&hub->tt.lock);
 617         INIT_LIST_HEAD (&hub->tt.clear_list);
 618         INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub);
 619         switch (hdev->descriptor.bDeviceProtocol) {
 620                 case 0:
 621                         break;
 622                 case 1:
 623                         dev_dbg(hub_dev, "Single TT\n");
 624                         hub->tt.hub = hdev;
 625                         break;
 626                 case 2:
 627                         ret = usb_set_interface(hdev, 0, 1);
 628                         if (ret == 0) {
 629                                 dev_dbg(hub_dev, "TT per port\n");
 630                                 hub->tt.multi = 1;
 631                         } else
 632                                 dev_err(hub_dev, "Using single TT (err %d)\n",
 633                                         ret);
 634                         hub->tt.hub = hdev;
 635                         break;
 636                 default:
 637                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
 638                                 hdev->descriptor.bDeviceProtocol);
 639                         break;
 640         }
 641
 642         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
 643         switch (wHubCharacteristics & HUB_CHAR_TTTT) {
 644                 case HUB_TTTT_8_BITS:
 645                         if (hdev->descriptor.bDeviceProtocol != 0) {
 646                                 hub->tt.think_time = 666;
 647                                 dev_dbg(hub_dev, "TT requires at most %d "
 648                                                 "FS bit times (%d ns)\n",
 649                                         8, hub->tt.think_time);
 650                         }
 651                         break;
 652                 case HUB_TTTT_16_BITS:
 653                         hub->tt.think_time = 666 * 2;
 654                         dev_dbg(hub_dev, "TT requires at most %d "
 655                                         "FS bit times (%d ns)\n",
 656                                 16, hub->tt.think_time);
 657                         break;
 658                 case HUB_TTTT_24_BITS:
 659                         hub->tt.think_time = 666 * 3;
 660                         dev_dbg(hub_dev, "TT requires at most %d "
 661                                         "FS bit times (%d ns)\n",
 662                                 24, hub->tt.think_time);
 663                         break;
 664                 case HUB_TTTT_32_BITS:
 665                         hub->tt.think_time = 666 * 4;
 666                         dev_dbg(hub_dev, "TT requires at most %d "
 667                                         "FS bit times (%d ns)\n",
 668                                 32, hub->tt.think_time);
 669                         break;
 670         }
 671
 672         /* probe() zeroes hub->indicator[] */
 673         if (wHubCharacteristics & HUB_CHAR_PORTIND) {
 674                 hub->has_indicators = 1;
 675                 dev_dbg(hub_dev, "Port indicators are supported\n");
 676         }
 677
 678         dev_dbg(hub_dev, "power on to power good time: %dms\n",
 679                 hub->descriptor->bPwrOn2PwrGood * 2);
 680
 681         /* power budgeting mostly matters with bus-powered hubs,
 682          * and battery-powered root hubs (may provide just 8 mA).
 683          */
 684         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
 685         if (ret < 0) {
 686                 message = "can't get hub status";
 687                 goto fail;
 688         }
 689         le16_to_cpus(&hubstatus);
 690         if (hdev == hdev->bus->root_hub) {
 691                 struct usb_hcd *hcd =
 692                                 container_of(hdev->bus, struct usb_hcd, self);
 693
 694                 hub->power_budget = min(500u, hcd->power_budget) / 2;
 695         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
 696                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
 697                         hub->descriptor->bHubContrCurrent);
 698                 hub->power_budget = (501 - hub->descriptor->bHubContrCurrent)
 699                                         / 2;
 700         }
 701         if (hub->power_budget)
 702                 dev_dbg(hub_dev, "%dmA bus power budget for children\n",
 703                         hub->power_budget * 2);
 704
 705
 706         ret = hub_hub_status(hub, &hubstatus, &hubchange);
 707         if (ret < 0) {
 708                 message = "can't get hub status";
 709                 goto fail;
 710         }
 711
 712         /* local power status reports aren't always correct */
 713         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
 714                 dev_dbg(hub_dev, "local power source is %s\n",
 715                         (hubstatus & HUB_STATUS_LOCAL_POWER)
 716                         ? "lost (inactive)" : "good");
 717
 718         if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
 719                 dev_dbg(hub_dev, "%sover-current condition exists\n",
 720                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
 721
 722         /* set up the interrupt endpoint */
 723         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
 724         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
 725
 726         if (maxp > sizeof(*hub->buffer))
 727                 maxp = sizeof(*hub->buffer);
 728
 729         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
 730         if (!hub->urb) {
 731                 message = "couldn't allocate interrupt urb";
 732                 ret = -ENOMEM;
 733                 goto fail;
 734         }
 735
 736         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
 737                 hub, endpoint->bInterval);
 738         hub->urb->transfer_dma = hub->buffer_dma;
 739         hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 740
 741         /* maybe cycle the hub leds */
 742         if (hub->has_indicators && blinkenlights)
 743                 hub->indicator [0] = INDICATOR_CYCLE;
 744
 745         hub_power_on(hub);
 746         hub_activate(hub);
 747         return 0;
 748
 749 fail:
 750         dev_err (hub_dev, "config failed, %s (err %d)\n",
 751                         message, ret);
 752         /* hub_disconnect() frees urb and descriptor */
 753         return ret;
 754 }
 755
 756 static unsigned highspeed_hubs;
 757
 758 /* Called after the hub driver is unbound from a hub with children */
 759 static void hub_remove_children_work(void *__hub)
 760 {
 761         struct usb_hub          *hub = __hub;
 762         struct usb_device       *hdev = hub->hdev;
 763         int                     i;
 764
 765         kfree(hub);
 766
 767         usb_lock_device(hdev);
 768         for (i = 0; i < hdev->maxchild; ++i) {
 769                 if (hdev->children[i])
 770                         usb_disconnect(&hdev->children[i]);
 771         }
 772         usb_unlock_device(hdev);
 773         usb_put_dev(hdev);
 774 }
 775
 776 static void hub_disconnect(struct usb_interface *intf)
 777 {
 778         struct usb_hub *hub = usb_get_intfdata (intf);
 779         struct usb_device *hdev;
 780         int n, port1;
 781
 782         usb_set_intfdata (intf, NULL);
 783         hdev = hub->hdev;
 784
 785         if (hdev->speed == USB_SPEED_HIGH)
 786                 highspeed_hubs--;
 787
 788         hub_quiesce(hub);
 789         usb_free_urb(hub->urb);
 790         hub->urb = NULL;
 791
 792         spin_lock_irq(&hub_event_lock);
 793         list_del_init(&hub->event_list);
 794         spin_unlock_irq(&hub_event_lock);
 795
 796         kfree(hub->descriptor);
 797         hub->descriptor = NULL;
 798
 799         kfree(hub->status);
 800         hub->status = NULL;
 801
 802         if (hub->buffer) {
 803                 usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
 804                                 hub->buffer_dma);
 805                 hub->buffer = NULL;
 806         }
 807
 808         /* If there are any children then this is an unbind only, not a
 809          * physical disconnection.  The active ports must be disabled
 810          * and later on we must call usb_disconnect().  We can't call
 811          * it now because we may not hold the hub's device lock.
 812          */
 813         n = 0;
 814         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
 815                 if (hdev->children[port1 - 1]) {
 816                         ++n;
 817                         hub_port_disable(hub, port1, 1);
 818                 }
 819         }
 820
 821         if (n == 0)
 822                 kfree(hub);
 823         else {
 824                 /* Reuse the hub->leds work_struct for our own purposes */
 825                 INIT_WORK(&hub->leds, hub_remove_children_work, hub);
 826                 schedule_work(&hub->leds);
 827                 usb_get_dev(hdev);
 828         }
 829 }
 830
 831 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
 832 {
 833         struct usb_host_interface *desc;
 834         struct usb_endpoint_descriptor *endpoint;
 835         struct usb_device *hdev;
 836         struct usb_hub *hub;
 837
 838         desc = intf->cur_altsetting;
 839         hdev = interface_to_usbdev(intf);
 840
 841         /* Some hubs have a subclass of 1, which AFAICT according to the */
 842         /*  specs is not defined, but it works */
 843         if ((desc->desc.bInterfaceSubClass != 0) &&
 844             (desc->desc.bInterfaceSubClass != 1)) {
 845 descriptor_error:
 846                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
 847                 return -EIO;
 848         }
 849
 850         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
 851         if (desc->desc.bNumEndpoints != 1)
 852                 goto descriptor_error;
 853
 854         endpoint = &desc->endpoint[0].desc;
 855
 856         /* Output endpoint? Curiouser and curiouser.. */
 857         if (!(endpoint->bEndpointAddress & USB_DIR_IN))
 858                 goto descriptor_error;
 859
 860         /* If it's not an interrupt endpoint, we'd better punt! */
 861         if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
 862                         != USB_ENDPOINT_XFER_INT)
 863                 goto descriptor_error;
 864
 865         /* We found a hub */
 866         dev_info (&intf->dev, "USB hub found\n");
 867
 868         hub = kzalloc(sizeof(*hub), GFP_KERNEL);
 869         if (!hub) {
 870                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
 871                 return -ENOMEM;
 872         }
 873
 874         INIT_LIST_HEAD(&hub->event_list);
 875         hub->intfdev = &intf->dev;
 876         hub->hdev = hdev;
 877         INIT_WORK(&hub->leds, led_work, hub);
 878
 879         usb_set_intfdata (intf, hub);
 880
 881         if (hdev->speed == USB_SPEED_HIGH)
 882                 highspeed_hubs++;
 883
 884         if (hub_configure(hub, endpoint) >= 0)
 885                 return 0;
 886
 887         hub_disconnect (intf);
 888         return -ENODEV;
 889 }
 890
 891 static int
 892 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
 893 {
 894         struct usb_device *hdev = interface_to_usbdev (intf);
 895
 896         /* assert ifno == 0 (part of hub spec) */
 897         switch (code) {
 898         case USBDEVFS_HUB_PORTINFO: {
 899                 struct usbdevfs_hub_portinfo *info = user_data;
 900                 int i;
 901
 902                 spin_lock_irq(&device_state_lock);
 903                 if (hdev->devnum <= 0)
 904                         info->nports = 0;
 905                 else {
 906                         info->nports = hdev->maxchild;
 907                         for (i = 0; i < info->nports; i++) {
 908                                 if (hdev->children[i] == NULL)
 909                                         info->port[i] = 0;
 910                                 else
 911                                         info->port[i] =
 912                                                 hdev->children[i]->devnum;
 913                         }
 914                 }
 915                 spin_unlock_irq(&device_state_lock);
 916
 917                 return info->nports + 1;
 918                 }
 919
 920         default:
 921                 return -ENOSYS;
 922         }
 923 }
 924
 925 /* caller has locked the hub device */
 926 static void hub_pre_reset(struct usb_hub *hub)
 927 {
 928         struct usb_device *hdev = hub->hdev;
 929         int i;
 930
 931         for (i = 0; i < hdev->maxchild; ++i) {
 932                 if (hdev->children[i])
 933                         usb_disconnect(&hdev->children[i]);
 934         }
 935         hub_quiesce(hub);
 936 }
 937
 938 /* caller has locked the hub device */
 939 static void hub_post_reset(struct usb_hub *hub)
 940 {
 941         hub_activate(hub);
 942         hub_power_on(hub);
 943 }
 944
 945
 946 /* grab device/port lock, returning index of that port (zero based).
 947  * protects the upstream link used by this device from concurrent
 948  * tree operations like suspend, resume, reset, and disconnect, which
 949  * apply to everything downstream of a given port.
 950  */
 951 static int locktree(struct usb_device *udev)
 952 {
 953         int                     t;
 954         struct usb_device       *hdev;
 955
 956         if (!udev)
 957                 return -ENODEV;
 958
 959         /* root hub is always the first lock in the series */
 960         hdev = udev->parent;
 961         if (!hdev) {
 962                 usb_lock_device(udev);
 963                 return 0;
 964         }
 965
 966         /* on the path from root to us, lock everything from
 967          * top down, dropping parent locks when not needed
 968          */
 969         t = locktree(hdev);
 970         if (t < 0)
 971                 return t;
 972         for (t = 0; t < hdev->maxchild; t++) {
 973                 if (hdev->children[t] == udev) {
 974                         /* everything is fail-fast once disconnect
 975                          * processing starts
 976                          */
 977                         if (udev->state == USB_STATE_NOTATTACHED)
 978                                 break;
 979
 980                         /* when everyone grabs locks top->bottom,
 981                          * non-overlapping work may be concurrent
 982                          */
 983                         down(&udev->serialize);
 984                         up(&hdev->serialize);
 985                         return t + 1;
 986                 }
 987         }
 988         usb_unlock_device(hdev);
 989         return -ENODEV;
 990 }
 991
 992 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
 993 {
 994         int i;
 995
 996         for (i = 0; i < udev->maxchild; ++i) {
 997                 if (udev->children[i])
 998                         recursively_mark_NOTATTACHED(udev->children[i]);
 999         }
1000         udev->state = USB_STATE_NOTATTACHED;
1001 }
1002
1003 /**
1004  * usb_set_device_state - change a device's current state (usbcore, hcds)
1005  * @udev: pointer to device whose state should be changed
1006  * @new_state: new state value to be stored
1007  *
1008  * udev->state is _not_ fully protected by the device lock.  Although
1009  * most transitions are made only while holding the lock, the state can
1010  * can change to USB_STATE_NOTATTACHED at almost any time.  This
1011  * is so that devices can be marked as disconnected as soon as possible,
1012  * without having to wait for any semaphores to be released.  As a result,
1013  * all changes to any device's state must be protected by the
1014  * device_state_lock spinlock.
1015  *
1016  * Once a device has been added to the device tree, all changes to its state
1017  * should be made using this routine.  The state should _not_ be set directly.
1018  *
1019  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1020  * Otherwise udev->state is set to new_state, and if new_state is
1021  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1022  * to USB_STATE_NOTATTACHED.
1023  */
1024 void usb_set_device_state(struct usb_device *udev,
1025                 enum usb_device_state new_state)
1026 {
1027         unsigned long flags;
1028
1029         spin_lock_irqsave(&device_state_lock, flags);
1030         if (udev->state == USB_STATE_NOTATTACHED)
1031                 ;       /* do nothing */
1032         else if (new_state != USB_STATE_NOTATTACHED) {
1033                 udev->state = new_state;
1034                 if (new_state == USB_STATE_CONFIGURED)
1035                         device_init_wakeup(&udev->dev,
1036                                 (udev->actconfig->desc.bmAttributes
1037                                  & USB_CONFIG_ATT_WAKEUP));
1038                 else if (new_state != USB_STATE_SUSPENDED)
1039                         device_init_wakeup(&udev->dev, 0);
1040         } else
1041                 recursively_mark_NOTATTACHED(udev);
1042         spin_unlock_irqrestore(&device_state_lock, flags);
1043 }
1044 EXPORT_SYMBOL(usb_set_device_state);
1045
1046
1047 static void choose_address(struct usb_device *udev)
1048 {
1049         int             devnum;
1050         struct usb_bus  *bus = udev->bus;
1051
1052         /* If khubd ever becomes multithreaded, this will need a lock */
1053
1054         /* Try to allocate the next devnum beginning at bus->devnum_next. */
1055         devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1056                         bus->devnum_next);
1057         if (devnum >= 128)
1058                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1059
1060         bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1061
1062         if (devnum < 128) {
1063                 set_bit(devnum, bus->devmap.devicemap);
1064                 udev->devnum = devnum;
1065         }
1066 }
1067
1068 static void release_address(struct usb_device *udev)
1069 {
1070         if (udev->devnum > 0) {
1071                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1072                 udev->devnum = -1;
1073         }
1074 }
1075
1076 /**
1077  * usb_disconnect - disconnect a device (usbcore-internal)
1078  * @pdev: pointer to device being disconnected
1079  * Context: !in_interrupt ()
1080  *
1081  * Something got disconnected. Get rid of it and all of its children.
1082  *
1083  * If *pdev is a normal device then the parent hub must already be locked.
1084  * If *pdev is a root hub then this routine will acquire the
1085  * usb_bus_list_lock on behalf of the caller.
1086  *
1087  * Only hub drivers (including virtual root hub drivers for host
1088  * controllers) should ever call this.
1089  *
1090  * This call is synchronous, and may not be used in an interrupt context.
1091  */
1092 void usb_disconnect(struct usb_device **pdev)
1093 {
1094         struct usb_device       *udev = *pdev;
1095         int                     i;
1096
1097         if (!udev) {
1098                 pr_debug ("%s nodev\n", __FUNCTION__);
1099                 return;
1100         }
1101
1102         /* mark the device as inactive, so any further urb submissions for
1103          * this device (and any of its children) will fail immediately.
1104          * this quiesces everyting except pending urbs.
1105          */
1106         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1107
1108         /* lock the bus list on behalf of HCDs unregistering their root hubs */
1109         if (!udev->parent) {
1110                 down(&usb_bus_list_lock);
1111                 usb_lock_device(udev);
1112         } else
1113                 down(&udev->serialize);
1114
1115         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1116
1117         /* Free up all the children before we remove this device */
1118         for (i = 0; i < USB_MAXCHILDREN; i++) {
1119                 if (udev->children[i])
1120                         usb_disconnect(&udev->children[i]);
1121         }
1122
1123         /* deallocate hcd/hardware state ... nuking all pending urbs and
1124          * cleaning up all state associated with the current configuration
1125          * so that the hardware is now fully quiesced.
1126          */
1127         usb_disable_device(udev, 0);
1128
1129         usb_notify_remove_device(udev);
1130
1131         /* Free the device number, remove the /proc/bus/usb entry and
1132          * the sysfs attributes, and delete the parent's children[]
1133          * (or root_hub) pointer.
1134          */
1135         dev_dbg (&udev->dev, "unregistering device\n");
1136         release_address(udev);
1137         usb_remove_sysfs_dev_files(udev);
1138
1139         /* Avoid races with recursively_mark_NOTATTACHED() */
1140         spin_lock_irq(&device_state_lock);
1141         *pdev = NULL;
1142         spin_unlock_irq(&device_state_lock);
1143
1144         if (!udev->parent) {
1145                 usb_unlock_device(udev);
1146                 up(&usb_bus_list_lock);
1147         } else
1148                 up(&udev->serialize);
1149
1150         device_unregister(&udev->dev);
1151 }
1152
1153 static int choose_configuration(struct usb_device *udev)
1154 {
1155         int c, i;
1156
1157         /* NOTE: this should interact with hub power budgeting */
1158
1159         c = udev->config[0].desc.bConfigurationValue;
1160         if (udev->descriptor.bNumConfigurations != 1) {
1161                 for (i = 0; i < udev->descriptor.bNumConfigurations; i++) {
1162                         struct usb_interface_descriptor *desc;
1163
1164                         /* heuristic:  Linux is more likely to have class
1165                          * drivers, so avoid vendor-specific interfaces.
1166                          */
1167                         desc = &udev->config[i].intf_cache[0]
1168                                         ->altsetting->desc;
1169                         if (desc->bInterfaceClass == USB_CLASS_VENDOR_SPEC)
1170                                 continue;
1171                         /* COMM/2/all is CDC ACM, except 0xff is MSFT RNDIS.
1172                          * MSFT needs this to be the first config; never use
1173                          * it as the default unless Linux has host-side RNDIS.
1174                          * A second config would ideally be CDC-Ethernet, but
1175                          * may instead be the "vendor specific" CDC subset
1176                          * long used by ARM Linux for sa1100 or pxa255.
1177                          */
1178                         if (desc->bInterfaceClass == USB_CLASS_COMM
1179                                         && desc->bInterfaceSubClass == 2
1180                                         && desc->bInterfaceProtocol == 0xff) {
1181                                 c = udev->config[1].desc.bConfigurationValue;
1182                                 continue;
1183                         }
1184                         c = udev->config[i].desc.bConfigurationValue;
1185                         break;
1186                 }
1187                 dev_info(&udev->dev,
1188                         "configuration #%d chosen from %d choices\n",
1189                         c, udev->descriptor.bNumConfigurations);
1190         }
1191         return c;
1192 }
1193
1194 #ifdef DEBUG
1195 static void show_string(struct usb_device *udev, char *id, char *string)
1196 {
1197         if (!string)
1198                 return;
1199         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1200 }
1201
1202 #else
1203 static inline void show_string(struct usb_device *udev, char *id, char *string)
1204 {}
1205 #endif
1206
1207
1208 #ifdef  CONFIG_USB_OTG
1209 #include "otg_whitelist.h"
1210 #endif
1211
1212 /**
1213  * usb_new_device - perform initial device setup (usbcore-internal)
1214  * @udev: newly addressed device (in ADDRESS state)
1215  *
1216  * This is called with devices which have been enumerated, but not yet
1217  * configured.  The device descriptor is available, but not descriptors
1218  * for any device configuration.  The caller must have locked udev and
1219  * either the parent hub (if udev is a normal device) or else the
1220  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1221  * udev has already been installed, but udev is not yet visible through
1222  * sysfs or other filesystem code.
1223  *
1224  * Returns 0 for success (device is configured and listed, with its
1225  * interfaces, in sysfs); else a negative errno value.
1226  *
1227  * This call is synchronous, and may not be used in an interrupt context.
1228  *
1229  * Only the hub driver should ever call this; root hub registration
1230  * uses it indirectly.
1231  */
1232 int usb_new_device(struct usb_device *udev)
1233 {
1234         int err;
1235         int c;
1236
1237         err = usb_get_configuration(udev);
1238         if (err < 0) {
1239                 dev_err(&udev->dev, "can't read configurations, error %d\n",
1240                         err);
1241                 goto fail;
1242         }
1243
1244         /* read the standard strings and cache them if present */
1245         udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1246         udev->manufacturer = usb_cache_string(udev,
1247                         udev->descriptor.iManufacturer);
1248         udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1249
1250         /* Tell the world! */
1251         dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1252                         "SerialNumber=%d\n",
1253                         udev->descriptor.iManufacturer,
1254                         udev->descriptor.iProduct,
1255                         udev->descriptor.iSerialNumber);
1256         show_string(udev, "Product", udev->product);
1257         show_string(udev, "Manufacturer", udev->manufacturer);
1258         show_string(udev, "SerialNumber", udev->serial);
1259
1260 #ifdef  CONFIG_USB_OTG
1261         /*
1262          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1263          * to wake us after we've powered off VBUS; and HNP, switching roles
1264          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1265          */
1266         if (!udev->bus->is_b_host
1267                         && udev->config
1268                         && udev->parent == udev->bus->root_hub) {
1269                 struct usb_otg_descriptor       *desc = 0;
1270                 struct usb_bus                  *bus = udev->bus;
1271
1272                 /* descriptor may appear anywhere in config */
1273                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1274                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1275                                         USB_DT_OTG, (void **) &desc) == 0) {
1276                         if (desc->bmAttributes & USB_OTG_HNP) {
1277                                 unsigned                port1;
1278                                 struct usb_device       *root = udev->parent;
1279
1280                                 for (port1 = 1; port1 <= root->maxchild;
1281                                                 port1++) {
1282                                         if (root->children[port1-1] == udev)
1283                                                 break;
1284                                 }
1285
1286                                 dev_info(&udev->dev,
1287                                         "Dual-Role OTG device on %sHNP port\n",
1288                                         (port1 == bus->otg_port)
1289                                                 ? "" : "non-");
1290
1291                                 /* enable HNP before suspend, it's simpler */
1292                                 if (port1 == bus->otg_port)
1293                                         bus->b_hnp_enable = 1;
1294                                 err = usb_control_msg(udev,
1295                                         usb_sndctrlpipe(udev, 0),
1296                                         USB_REQ_SET_FEATURE, 0,
1297                                         bus->b_hnp_enable
1298                                                 ? USB_DEVICE_B_HNP_ENABLE
1299                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1300                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1301                                 if (err < 0) {
1302                                         /* OTG MESSAGE: report errors here,
1303                                          * customize to match your product.
1304                                          */
1305                                         dev_info(&udev->dev,
1306                                                 "can't set HNP mode; %d\n",
1307                                                 err);
1308                                         bus->b_hnp_enable = 0;
1309                                 }
1310                         }
1311                 }
1312         }
1313
1314         if (!is_targeted(udev)) {
1315
1316                 /* Maybe it can talk to us, though we can't talk to it.
1317                  * (Includes HNP test device.)
1318                  */
1319                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1320                         static int __usb_suspend_device(struct usb_device *,
1321                                                 int port1);
1322                         err = __usb_suspend_device(udev, udev->bus->otg_port);
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         usb_notify_add_device(udev);
1359
1360         return 0;
1361
1362 fail:
1363         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1364         return err;
1365 }
1366
1367
1368 static int hub_port_status(struct usb_hub *hub, int port1,
1369                                u16 *status, u16 *change)
1370 {
1371         int ret;
1372
1373         ret = get_port_status(hub->hdev, port1, &hub->status->port);
1374         if (ret < 0)
1375                 dev_err (hub->intfdev,
1376                         "%s failed (err = %d)\n", __FUNCTION__, ret);
1377         else {
1378                 *status = le16_to_cpu(hub->status->port.wPortStatus);
1379                 *change = le16_to_cpu(hub->status->port.wPortChange);
1380                 ret = 0;
1381         }
1382         return ret;
1383 }
1384
1385 #define PORT_RESET_TRIES        5
1386 #define SET_ADDRESS_TRIES       2
1387 #define GET_DESCRIPTOR_TRIES    2
1388 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1389 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1390
1391 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1392 #define HUB_SHORT_RESET_TIME    10
1393 #define HUB_LONG_RESET_TIME     200
1394 #define HUB_RESET_TIMEOUT       500
1395
1396 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1397                                 struct usb_device *udev, unsigned int delay)
1398 {
1399         int delay_time, ret;
1400         u16 portstatus;
1401         u16 portchange;
1402
1403         for (delay_time = 0;
1404                         delay_time < HUB_RESET_TIMEOUT;
1405                         delay_time += delay) {
1406                 /* wait to give the device a chance to reset */
1407                 msleep(delay);
1408
1409                 /* read and decode port status */
1410                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1411                 if (ret < 0)
1412                         return ret;
1413
1414                 /* Device went away? */
1415                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1416                         return -ENOTCONN;
1417
1418                 /* bomb out completely if something weird happened */
1419                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1420                         return -EINVAL;
1421
1422                 /* if we`ve finished resetting, then break out of the loop */
1423                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1424                     (portstatus & USB_PORT_STAT_ENABLE)) {
1425                         if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1426                                 udev->speed = USB_SPEED_HIGH;
1427                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1428                                 udev->speed = USB_SPEED_LOW;
1429                         else
1430                                 udev->speed = USB_SPEED_FULL;
1431                         return 0;
1432                 }
1433
1434                 /* switch to the long delay after two short delay failures */
1435                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1436                         delay = HUB_LONG_RESET_TIME;
1437
1438                 dev_dbg (hub->intfdev,
1439                         "port %d not reset yet, waiting %dms\n",
1440                         port1, delay);
1441         }
1442
1443         return -EBUSY;
1444 }
1445
1446 static int hub_port_reset(struct usb_hub *hub, int port1,
1447                                 struct usb_device *udev, unsigned int delay)
1448 {
1449         int i, status;
1450
1451         /* Reset the port */
1452         for (i = 0; i < PORT_RESET_TRIES; i++) {
1453                 status = set_port_feature(hub->hdev,
1454                                 port1, USB_PORT_FEAT_RESET);
1455                 if (status)
1456                         dev_err(hub->intfdev,
1457                                         "cannot reset port %d (err = %d)\n",
1458                                         port1, status);
1459                 else {
1460                         status = hub_port_wait_reset(hub, port1, udev, delay);
1461                         if (status && status != -ENOTCONN)
1462                                 dev_dbg(hub->intfdev,
1463                                                 "port_wait_reset: err = %d\n",
1464                                                 status);
1465                 }
1466
1467                 /* return on disconnect or reset */
1468                 switch (status) {
1469                 case 0:
1470                         /* TRSTRCY = 10 ms; plus some extra */
1471                         msleep(10 + 40);
1472                         /* FALL THROUGH */
1473                 case -ENOTCONN:
1474                 case -ENODEV:
1475                         clear_port_feature(hub->hdev,
1476                                 port1, USB_PORT_FEAT_C_RESET);
1477                         /* FIXME need disconnect() for NOTATTACHED device */
1478                         usb_set_device_state(udev, status
1479                                         ? USB_STATE_NOTATTACHED
1480                                         : USB_STATE_DEFAULT);
1481                         return status;
1482                 }
1483
1484                 dev_dbg (hub->intfdev,
1485                         "port %d not enabled, trying reset again...\n",
1486                         port1);
1487                 delay = HUB_LONG_RESET_TIME;
1488         }
1489
1490         dev_err (hub->intfdev,
1491                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1492                 port1);
1493
1494         return status;
1495 }
1496
1497 /*
1498  * Disable a port and mark a logical connnect-change event, so that some
1499  * time later khubd will disconnect() any existing usb_device on the port
1500  * and will re-enumerate if there actually is a device attached.
1501  */
1502 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1503 {
1504         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1505         hub_port_disable(hub, port1, 1);
1506
1507         /* FIXME let caller ask to power down the port:
1508          *  - some devices won't enumerate without a VBUS power cycle
1509          *  - SRP saves power that way
1510          *  - ... new call, TBD ...
1511          * That's easy if this hub can switch power per-port, and
1512          * khubd reactivates the port later (timer, SRP, etc).
1513          * Powerdown must be optional, because of reset/DFU.
1514          */
1515
1516         set_bit(port1, hub->change_bits);
1517         kick_khubd(hub);
1518 }
1519
1520
1521 #ifdef  CONFIG_USB_SUSPEND
1522
1523 /*
1524  * Selective port suspend reduces power; most suspended devices draw
1525  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1526  * All devices below the suspended port are also suspended.
1527  *
1528  * Devices leave suspend state when the host wakes them up.  Some devices
1529  * also support "remote wakeup", where the device can activate the USB
1530  * tree above them to deliver data, such as a keypress or packet.  In
1531  * some cases, this wakes the USB host.
1532  */
1533 static int hub_port_suspend(struct usb_hub *hub, int port1,
1534                 struct usb_device *udev)
1535 {
1536         int     status;
1537
1538         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1539
1540         /* enable remote wakeup when appropriate; this lets the device
1541          * wake up the upstream hub (including maybe the root hub).
1542          *
1543          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1544          * we don't explicitly enable it here.
1545          */
1546         if (device_may_wakeup(&udev->dev)) {
1547                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1548                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1549                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1550                                 NULL, 0,
1551                                 USB_CTRL_SET_TIMEOUT);
1552                 if (status)
1553                         dev_dbg(&udev->dev,
1554                                 "won't remote wakeup, status %d\n",
1555                                 status);
1556         }
1557
1558         /* see 7.1.7.6 */
1559         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1560         if (status) {
1561                 dev_dbg(hub->intfdev,
1562                         "can't suspend port %d, status %d\n",
1563                         port1, status);
1564                 /* paranoia:  "should not happen" */
1565                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1566                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1567                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1568                                 NULL, 0,
1569                                 USB_CTRL_SET_TIMEOUT);
1570         } else {
1571                 /* device has up to 10 msec to fully suspend */
1572                 dev_dbg(&udev->dev, "usb suspend\n");
1573                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1574                 msleep(10);
1575         }
1576         return status;
1577 }
1578
1579 /*
1580  * Devices on USB hub ports have only one "suspend" state, corresponding
1581  * to ACPI D2, "may cause the device to lose some context".
1582  * State transitions include:
1583  *
1584  *   - suspend, resume ... when the VBUS power link stays live
1585  *   - suspend, disconnect ... VBUS lost
1586  *
1587  * Once VBUS drop breaks the circuit, the port it's using has to go through
1588  * normal re-enumeration procedures, starting with enabling VBUS power.
1589  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1590  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1591  * timer, no SRP, no requests through sysfs.
1592  *
1593  * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1594  * the root hub for their bus goes into global suspend ... so we don't
1595  * (falsely) update the device power state to say it suspended.
1596  */
1597 static int __usb_suspend_device (struct usb_device *udev, int port1)
1598 {
1599         int     status = 0;
1600
1601         /* caller owns the udev device lock */
1602         if (port1 < 0)
1603                 return port1;
1604
1605         if (udev->state == USB_STATE_SUSPENDED
1606                         || udev->state == USB_STATE_NOTATTACHED) {
1607                 return 0;
1608         }
1609
1610         /* all interfaces must already be suspended */
1611         if (udev->actconfig) {
1612                 int     i;
1613
1614                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1615                         struct usb_interface    *intf;
1616
1617                         intf = udev->actconfig->interface[i];
1618                         if (is_active(intf)) {
1619                                 dev_dbg(&intf->dev, "nyet suspended\n");
1620                                 return -EBUSY;
1621                         }
1622                 }
1623         }
1624
1625         /* we only change a device's upstream USB link.
1626          * root hubs have no upstream USB link.
1627          */
1628         if (udev->parent)
1629                 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1630                                 udev);
1631
1632         if (status == 0)
1633                 udev->dev.power.power_state = PMSG_SUSPEND;
1634         return status;
1635 }
1636
1637 #endif
1638
1639 /*
1640  * usb_suspend_device - suspend a usb device
1641  * @udev: device that's no longer in active use
1642  * Context: must be able to sleep; device not locked; pm locks held
1643  *
1644  * Suspends a USB device that isn't in active use, conserving power.
1645  * Devices may wake out of a suspend, if anything important happens,
1646  * using the remote wakeup mechanism.  They may also be taken out of
1647  * suspend by the host, using usb_resume_device().  It's also routine
1648  * to disconnect devices while they are suspended.
1649  *
1650  * This only affects the USB hardware for a device; its interfaces
1651  * (and, for hubs, child devices) must already have been suspended.
1652  *
1653  * Suspending OTG devices may trigger HNP, if that's been enabled
1654  * between a pair of dual-role devices.  That will change roles, such
1655  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1656  *
1657  * Returns 0 on success, else negative errno.
1658  */
1659 int usb_suspend_device(struct usb_device *udev)
1660 {
1661 #ifdef  CONFIG_USB_SUSPEND
1662         int     port1, status;
1663
1664         port1 = locktree(udev);
1665         if (port1 < 0)
1666                 return port1;
1667
1668         status = __usb_suspend_device(udev, port1);
1669         usb_unlock_device(udev);
1670         return status;
1671 #else
1672         /* NOTE:  udev->state unchanged, it's not lying ... */
1673         udev->dev.power.power_state = PMSG_SUSPEND;
1674         return 0;
1675 #endif
1676 }
1677 EXPORT_SYMBOL_GPL(usb_suspend_device);
1678
1679 /*
1680  * If the USB "suspend" state is in use (rather than "global suspend"),
1681  * many devices will be individually taken out of suspend state using
1682  * special" resume" signaling.  These routines kick in shortly after
1683  * hardware resume signaling is finished, either because of selective
1684  * resume (by host) or remote wakeup (by device) ... now see what changed
1685  * in the tree that's rooted at this device.
1686  */
1687 static int finish_device_resume(struct usb_device *udev)
1688 {
1689         int     status;
1690         u16     devstatus;
1691
1692         /* caller owns the udev device lock */
1693         dev_dbg(&udev->dev, "finish resume\n");
1694
1695         /* usb ch9 identifies four variants of SUSPENDED, based on what
1696          * state the device resumes to.  Linux currently won't see the
1697          * first two on the host side; they'd be inside hub_port_init()
1698          * during many timeouts, but khubd can't suspend until later.
1699          */
1700         usb_set_device_state(udev, udev->actconfig
1701                         ? USB_STATE_CONFIGURED
1702                         : USB_STATE_ADDRESS);
1703
1704         /* 10.5.4.5 says be sure devices in the tree are still there.
1705          * For now let's assume the device didn't go crazy on resume,
1706          * and device drivers will know about any resume quirks.
1707          */
1708         status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1709         if (status < 0)
1710                 dev_dbg(&udev->dev,
1711                         "gone after usb resume? status %d\n",
1712                         status);
1713         else if (udev->actconfig) {
1714                 unsigned        i;
1715                 int             (*resume)(struct device *);
1716
1717                 le16_to_cpus(&devstatus);
1718                 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)
1719                                 && udev->parent) {
1720                         status = usb_control_msg(udev,
1721                                         usb_sndctrlpipe(udev, 0),
1722                                         USB_REQ_CLEAR_FEATURE,
1723                                                 USB_RECIP_DEVICE,
1724                                         USB_DEVICE_REMOTE_WAKEUP, 0,
1725                                         NULL, 0,
1726                                         USB_CTRL_SET_TIMEOUT);
1727                         if (status) {
1728                                 dev_dbg(&udev->dev, "disable remote "
1729                                         "wakeup, status %d\n", status);
1730                                 status = 0;
1731                         }
1732                 }
1733
1734                 /* resume interface drivers; if this is a hub, it
1735                  * may have a child resume event to deal with soon
1736                  */
1737                 resume = udev->dev.bus->resume;
1738                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++)
1739                         (void) resume(&udev->actconfig->interface[i]->dev);
1740                 status = 0;
1741
1742         } else if (udev->devnum <= 0) {
1743                 dev_dbg(&udev->dev, "bogus resume!\n");
1744                 status = -EINVAL;
1745         }
1746         return status;
1747 }
1748
1749 #ifdef  CONFIG_USB_SUSPEND
1750
1751 static int
1752 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1753 {
1754         int     status;
1755
1756         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1757
1758         /* see 7.1.7.7; affects power usage, but not budgeting */
1759         status = clear_port_feature(hub->hdev,
1760                         port1, USB_PORT_FEAT_SUSPEND);
1761         if (status) {
1762                 dev_dbg(hub->intfdev,
1763                         "can't resume port %d, status %d\n",
1764                         port1, status);
1765         } else {
1766                 u16             devstatus;
1767                 u16             portchange;
1768
1769                 /* drive resume for at least 20 msec */
1770                 if (udev)
1771                         dev_dbg(&udev->dev, "RESUME\n");
1772                 msleep(25);
1773
1774 #define LIVE_FLAGS      ( USB_PORT_STAT_POWER \
1775                         | USB_PORT_STAT_ENABLE \
1776                         | USB_PORT_STAT_CONNECTION)
1777
1778                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1779                  * stop resume signaling.  Then finish the resume
1780                  * sequence.
1781                  */
1782                 devstatus = portchange = 0;
1783                 status = hub_port_status(hub, port1,
1784                                 &devstatus, &portchange);
1785                 if (status < 0
1786                                 || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
1787                                 || (devstatus & USB_PORT_STAT_SUSPEND) != 0
1788                                 ) {
1789                         dev_dbg(hub->intfdev,
1790                                 "port %d status %04x.%04x after resume, %d\n",
1791                                 port1, portchange, devstatus, status);
1792                 } else {
1793                         /* TRSMRCY = 10 msec */
1794                         msleep(10);
1795                         if (udev)
1796                                 status = finish_device_resume(udev);
1797                 }
1798         }
1799         if (status < 0)
1800                 hub_port_logical_disconnect(hub, port1);
1801
1802         return status;
1803 }
1804
1805 #endif
1806
1807 /*
1808  * usb_resume_device - re-activate a suspended usb device
1809  * @udev: device to re-activate
1810  * Context: must be able to sleep; device not locked; pm locks held
1811  *
1812  * This will re-activate the suspended device, increasing power usage
1813  * while letting drivers communicate again with its endpoints.
1814  * USB resume explicitly guarantees that the power session between
1815  * the host and the device is the same as it was when the device
1816  * suspended.
1817  *
1818  * Returns 0 on success, else negative errno.
1819  */
1820 int usb_resume_device(struct usb_device *udev)
1821 {
1822         int     port1, status;
1823
1824         port1 = locktree(udev);
1825         if (port1 < 0)
1826                 return port1;
1827
1828 #ifdef  CONFIG_USB_SUSPEND
1829         /* selective resume of one downstream hub-to-device port */
1830         if (udev->parent) {
1831                 if (udev->state == USB_STATE_SUSPENDED) {
1832                         // NOTE swsusp may bork us, device state being wrong...
1833                         // NOTE this fails if parent is also suspended...
1834                         status = hub_port_resume(hdev_to_hub(udev->parent),
1835                                         port1, udev);
1836                 } else
1837                         status = 0;
1838         } else
1839 #endif
1840                 status = finish_device_resume(udev);
1841         if (status < 0)
1842                 dev_dbg(&udev->dev, "can't resume, status %d\n",
1843                         status);
1844
1845         usb_unlock_device(udev);
1846
1847         /* rebind drivers that had no suspend() */
1848         if (status == 0) {
1849                 usb_lock_all_devices();
1850                 bus_rescan_devices(&usb_bus_type);
1851                 usb_unlock_all_devices();
1852         }
1853         return status;
1854 }
1855
1856 static int remote_wakeup(struct usb_device *udev)
1857 {
1858         int     status = 0;
1859
1860 #ifdef  CONFIG_USB_SUSPEND
1861
1862         /* don't repeat RESUME sequence if this device
1863          * was already woken up by some other task
1864          */
1865         down(&udev->serialize);
1866         if (udev->state == USB_STATE_SUSPENDED) {
1867                 dev_dbg(&udev->dev, "RESUME (wakeup)\n");
1868                 /* TRSMRCY = 10 msec */
1869                 msleep(10);
1870                 status = finish_device_resume(udev);
1871         }
1872         up(&udev->serialize);
1873 #endif
1874         return status;
1875 }
1876
1877 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
1878 {
1879         struct usb_hub          *hub = usb_get_intfdata (intf);
1880         struct usb_device       *hdev = hub->hdev;
1881         unsigned                port1;
1882
1883         /* fail if children aren't already suspended */
1884         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1885                 struct usb_device       *udev;
1886
1887                 udev = hdev->children [port1-1];
1888                 if (udev && (udev->dev.power.power_state.event
1889                                         == PM_EVENT_ON
1890 #ifdef  CONFIG_USB_SUSPEND
1891                                 || udev->state != USB_STATE_SUSPENDED
1892 #endif
1893                                 )) {
1894                         dev_dbg(&intf->dev, "port %d nyet suspended\n", port1);
1895                         return -EBUSY;
1896                 }
1897         }
1898
1899         /* "global suspend" of the downstream HC-to-USB interface */
1900         if (!hdev->parent) {
1901                 struct usb_bus  *bus = hdev->bus;
1902                 if (bus) {
1903                         int     status = hcd_bus_suspend (bus);
1904
1905                         if (status != 0) {
1906                                 dev_dbg(&hdev->dev, "'global' suspend %d\n",
1907                                         status);
1908                                 return status;
1909                         }
1910                 } else
1911                         return -EOPNOTSUPP;
1912         }
1913
1914         /* stop khubd and related activity */
1915         hub_quiesce(hub);
1916         return 0;
1917 }
1918
1919 static int hub_resume(struct usb_interface *intf)
1920 {
1921         struct usb_device       *hdev = interface_to_usbdev(intf);
1922         struct usb_hub          *hub = usb_get_intfdata (intf);
1923         int                     status;
1924
1925         /* "global resume" of the downstream HC-to-USB interface */
1926         if (!hdev->parent) {
1927                 struct usb_bus  *bus = hdev->bus;
1928                 if (bus) {
1929                         status = hcd_bus_resume (bus);
1930                         if (status) {
1931                                 dev_dbg(&intf->dev, "'global' resume %d\n",
1932                                         status);
1933                                 return status;
1934                         }
1935                 } else
1936                         return -EOPNOTSUPP;
1937                 if (status == 0) {
1938                         /* TRSMRCY = 10 msec */
1939                         msleep(10);
1940                 }
1941         }
1942
1943         hub_activate(hub);
1944
1945         /* REVISIT:  this recursion probably shouldn't exist.  Remove
1946          * this code sometime, after retesting with different root and
1947          * external hubs.
1948          */
1949 #ifdef  CONFIG_USB_SUSPEND
1950         {
1951         unsigned                port1;
1952
1953         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1954                 struct usb_device       *udev;
1955                 u16                     portstat, portchange;
1956
1957                 udev = hdev->children [port1-1];
1958                 status = hub_port_status(hub, port1, &portstat, &portchange);
1959                 if (status == 0) {
1960                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
1961                                 clear_port_feature(hdev, port1,
1962                                         USB_PORT_FEAT_C_SUSPEND);
1963                                 portchange &= ~USB_PORT_STAT_C_SUSPEND;
1964                         }
1965
1966                         /* let khubd handle disconnects etc */
1967                         if (portchange)
1968                                 continue;
1969                 }
1970
1971                 if (!udev || status < 0)
1972                         continue;
1973                 down (&udev->serialize);
1974                 if (portstat & USB_PORT_STAT_SUSPEND)
1975                         status = hub_port_resume(hub, port1, udev);
1976                 else {
1977                         status = finish_device_resume(udev);
1978                         if (status < 0) {
1979                                 dev_dbg(&intf->dev, "resume port %d --> %d\n",
1980                                         port1, status);
1981                                 hub_port_logical_disconnect(hub, port1);
1982                         }
1983                 }
1984                 up(&udev->serialize);
1985         }
1986         }
1987 #endif
1988         return 0;
1989 }
1990
1991 void usb_suspend_root_hub(struct usb_device *hdev)
1992 {
1993         struct usb_hub *hub = hdev_to_hub(hdev);
1994
1995         /* This also makes any led blinker stop retriggering.  We're called
1996          * from irq, so the blinker might still be scheduled.  Caller promises
1997          * that the root hub status URB will be canceled.
1998          */
1999         __hub_quiesce(hub);
2000         mark_quiesced(to_usb_interface(hub->intfdev));
2001 }
2002
2003 void usb_resume_root_hub(struct usb_device *hdev)
2004 {
2005         struct usb_hub *hub = hdev_to_hub(hdev);
2006
2007         hub->resume_root_hub = 1;
2008         kick_khubd(hub);
2009 }
2010
2011
2012 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2013  *
2014  * Between connect detection and reset signaling there must be a delay
2015  * of 100ms at least for debounce and power-settling.  The corresponding
2016  * timer shall restart whenever the downstream port detects a disconnect.
2017  *
2018  * Apparently there are some bluetooth and irda-dongles and a number of
2019  * low-speed devices for which this debounce period may last over a second.
2020  * Not covered by the spec - but easy to deal with.
2021  *
2022  * This implementation uses a 1500ms total debounce timeout; if the
2023  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
2024  * every 25ms for transient disconnects.  When the port status has been
2025  * unchanged for 100ms it returns the port status.
2026  */
2027
2028 #define HUB_DEBOUNCE_TIMEOUT    1500
2029 #define HUB_DEBOUNCE_STEP         25
2030 #define HUB_DEBOUNCE_STABLE      100
2031
2032 static int hub_port_debounce(struct usb_hub *hub, int port1)
2033 {
2034         int ret;
2035         int total_time, stable_time = 0;
2036         u16 portchange, portstatus;
2037         unsigned connection = 0xffff;
2038
2039         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2040                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2041                 if (ret < 0)
2042                         return ret;
2043
2044                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2045                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2046                         stable_time += HUB_DEBOUNCE_STEP;
2047                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2048                                 break;
2049                 } else {
2050                         stable_time = 0;
2051                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2052                 }
2053
2054                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2055                         clear_port_feature(hub->hdev, port1,
2056                                         USB_PORT_FEAT_C_CONNECTION);
2057                 }
2058
2059                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2060                         break;
2061                 msleep(HUB_DEBOUNCE_STEP);
2062         }
2063
2064         dev_dbg (hub->intfdev,
2065                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2066                 port1, total_time, stable_time, portstatus);
2067
2068         if (stable_time < HUB_DEBOUNCE_STABLE)
2069                 return -ETIMEDOUT;
2070         return portstatus;
2071 }
2072
2073 static void ep0_reinit(struct usb_device *udev)
2074 {
2075         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2076         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2077         udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2078 }
2079
2080 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2081 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2082
2083 static int hub_set_address(struct usb_device *udev)
2084 {
2085         int retval;
2086
2087         if (udev->devnum == 0)
2088                 return -EINVAL;
2089         if (udev->state == USB_STATE_ADDRESS)
2090                 return 0;
2091         if (udev->state != USB_STATE_DEFAULT)
2092                 return -EINVAL;
2093         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2094                 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2095                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2096         if (retval == 0) {
2097                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2098                 ep0_reinit(udev);
2099         }
2100         return retval;
2101 }
2102
2103 /* Reset device, (re)assign address, get device descriptor.
2104  * Device connection must be stable, no more debouncing needed.
2105  * Returns device in USB_STATE_ADDRESS, except on error.
2106  *
2107  * If this is called for an already-existing device (as part of
2108  * usb_reset_device), the caller must own the device lock.  For a
2109  * newly detected device that is not accessible through any global
2110  * pointers, it's not necessary to lock the device.
2111  */
2112 static int
2113 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2114                 int retry_counter)
2115 {
2116         static DECLARE_MUTEX(usb_address0_sem);
2117
2118         struct usb_device       *hdev = hub->hdev;
2119         int                     i, j, retval;
2120         unsigned                delay = HUB_SHORT_RESET_TIME;
2121         enum usb_device_speed   oldspeed = udev->speed;
2122
2123         /* root hub ports have a slightly longer reset period
2124          * (from USB 2.0 spec, section 7.1.7.5)
2125          */
2126         if (!hdev->parent) {
2127                 delay = HUB_ROOT_RESET_TIME;
2128                 if (port1 == hdev->bus->otg_port)
2129                         hdev->bus->b_hnp_enable = 0;
2130         }
2131
2132         /* Some low speed devices have problems with the quick delay, so */
2133         /*  be a bit pessimistic with those devices. RHbug #23670 */
2134         if (oldspeed == USB_SPEED_LOW)
2135                 delay = HUB_LONG_RESET_TIME;
2136
2137         down(&usb_address0_sem);
2138
2139         /* Reset the device; full speed may morph to high speed */
2140         retval = hub_port_reset(hub, port1, udev, delay);
2141         if (retval < 0)         /* error or disconnect */
2142                 goto fail;
2143                                 /* success, speed is known */
2144         retval = -ENODEV;
2145
2146         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2147                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2148                 goto fail;
2149         }
2150         oldspeed = udev->speed;
2151
2152         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2153          * it's fixed size except for full speed devices.
2154          */
2155         switch (udev->speed) {
2156         case USB_SPEED_HIGH:            /* fixed at 64 */
2157                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2158                 break;
2159         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2160                 /* to determine the ep0 maxpacket size, try to read
2161                  * the device descriptor to get bMaxPacketSize0 and
2162                  * then correct our initial guess.
2163                  */
2164                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2165                 break;
2166         case USB_SPEED_LOW:             /* fixed at 8 */
2167                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2168                 break;
2169         default:
2170                 goto fail;
2171         }
2172
2173         dev_info (&udev->dev,
2174                         "%s %s speed USB device using %s and address %d\n",
2175                         (udev->config) ? "reset" : "new",
2176                         ({ char *speed; switch (udev->speed) {
2177                         case USB_SPEED_LOW:     speed = "low";  break;
2178                         case USB_SPEED_FULL:    speed = "full"; break;
2179                         case USB_SPEED_HIGH:    speed = "high"; break;
2180                         default:                speed = "?";    break;
2181                         }; speed;}),
2182                         udev->bus->controller->driver->name,
2183                         udev->devnum);
2184
2185         /* Set up TT records, if needed  */
2186         if (hdev->tt) {
2187                 udev->tt = hdev->tt;
2188                 udev->ttport = hdev->ttport;
2189         } else if (udev->speed != USB_SPEED_HIGH
2190                         && hdev->speed == USB_SPEED_HIGH) {
2191                 udev->tt = &hub->tt;
2192                 udev->ttport = port1;
2193         }
2194
2195         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2196          * Because device hardware and firmware is sometimes buggy in
2197          * this area, and this is how Linux has done it for ages.
2198          * Change it cautiously.
2199          *
2200          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2201          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2202          * so it may help with some non-standards-compliant devices.
2203          * Otherwise we start with SET_ADDRESS and then try to read the
2204          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2205          * value.
2206          */
2207         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2208                 if (USE_NEW_SCHEME(retry_counter)) {
2209                         struct usb_device_descriptor *buf;
2210                         int r = 0;
2211
2212 #define GET_DESCRIPTOR_BUFSIZE  64
2213                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2214                         if (!buf) {
2215                                 retval = -ENOMEM;
2216                                 continue;
2217                         }
2218
2219                         /* Use a short timeout the first time through,
2220                          * so that recalcitrant full-speed devices with
2221                          * 8- or 16-byte ep0-maxpackets won't slow things
2222                          * down tremendously by NAKing the unexpectedly
2223                          * early status stage.  Also, retry on all errors;
2224                          * some devices are flakey.
2225                          */
2226                         for (j = 0; j < 3; ++j) {
2227                                 buf->bMaxPacketSize0 = 0;
2228                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2229                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2230                                         USB_DT_DEVICE << 8, 0,
2231                                         buf, GET_DESCRIPTOR_BUFSIZE,
2232                                         (i ? USB_CTRL_GET_TIMEOUT : 1000));
2233                                 switch (buf->bMaxPacketSize0) {
2234                                 case 8: case 16: case 32: case 64:
2235                                         if (buf->bDescriptorType ==
2236                                                         USB_DT_DEVICE) {
2237                                                 r = 0;
2238                                                 break;
2239                                         }
2240                                         /* FALL THROUGH */
2241                                 default:
2242                                         if (r == 0)
2243                                                 r = -EPROTO;
2244                                         break;
2245                                 }
2246                                 if (r == 0)
2247                                         break;
2248                         }
2249                         udev->descriptor.bMaxPacketSize0 =
2250                                         buf->bMaxPacketSize0;
2251                         kfree(buf);
2252
2253                         retval = hub_port_reset(hub, port1, udev, delay);
2254                         if (retval < 0)         /* error or disconnect */
2255                                 goto fail;
2256                         if (oldspeed != udev->speed) {
2257                                 dev_dbg(&udev->dev,
2258                                         "device reset changed speed!\n");
2259                                 retval = -ENODEV;
2260                                 goto fail;
2261                         }
2262                         if (r) {
2263                                 dev_err(&udev->dev, "device descriptor "
2264                                                 "read/%s, error %d\n",
2265                                                 "64", r);
2266                                 retval = -EMSGSIZE;
2267                                 continue;
2268                         }
2269 #undef GET_DESCRIPTOR_BUFSIZE
2270                 }
2271
2272                 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2273                         retval = hub_set_address(udev);
2274                         if (retval >= 0)
2275                                 break;
2276                         msleep(200);
2277                 }
2278                 if (retval < 0) {
2279                         dev_err(&udev->dev,
2280                                 "device not accepting address %d, error %d\n",
2281                                 udev->devnum, retval);
2282                         goto fail;
2283                 }
2284
2285                 /* cope with hardware quirkiness:
2286                  *  - let SET_ADDRESS settle, some device hardware wants it
2287                  *  - read ep0 maxpacket even for high and low speed,
2288                  */
2289                 msleep(10);
2290                 if (USE_NEW_SCHEME(retry_counter))
2291                         break;
2292
2293                 retval = usb_get_device_descriptor(udev, 8);
2294                 if (retval < 8) {
2295                         dev_err(&udev->dev, "device descriptor "
2296                                         "read/%s, error %d\n",
2297                                         "8", retval);
2298                         if (retval >= 0)
2299                                 retval = -EMSGSIZE;
2300                 } else {
2301                         retval = 0;
2302                         break;
2303                 }
2304         }
2305         if (retval)
2306                 goto fail;
2307
2308         i = udev->descriptor.bMaxPacketSize0;
2309         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2310                 if (udev->speed != USB_SPEED_FULL ||
2311                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2312                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2313                         retval = -EMSGSIZE;
2314                         goto fail;
2315                 }
2316                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2317                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2318                 ep0_reinit(udev);
2319         }
2320
2321         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2322         if (retval < (signed)sizeof(udev->descriptor)) {
2323                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2324                         "all", retval);
2325                 if (retval >= 0)
2326                         retval = -ENOMSG;
2327                 goto fail;
2328         }
2329
2330         retval = 0;
2331
2332 fail:
2333         if (retval)
2334                 hub_port_disable(hub, port1, 0);
2335         up(&usb_address0_sem);
2336         return retval;
2337 }
2338
2339 static void
2340 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2341 {
2342         struct usb_qualifier_descriptor *qual;
2343         int                             status;
2344
2345         qual = kmalloc (sizeof *qual, SLAB_KERNEL);
2346         if (qual == NULL)
2347                 return;
2348
2349         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2350                         qual, sizeof *qual);
2351         if (status == sizeof *qual) {
2352                 dev_info(&udev->dev, "not running at top speed; "
2353                         "connect to a high speed hub\n");
2354                 /* hub LEDs are probably harder to miss than syslog */
2355                 if (hub->has_indicators) {
2356                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2357                         schedule_work (&hub->leds);
2358                 }
2359         }
2360         kfree(qual);
2361 }
2362
2363 static unsigned
2364 hub_power_remaining (struct usb_hub *hub)
2365 {
2366         struct usb_device *hdev = hub->hdev;
2367         int remaining;
2368         unsigned i;
2369
2370         remaining = hub->power_budget;
2371         if (!remaining)         /* self-powered */
2372                 return 0;
2373
2374         for (i = 0; i < hdev->maxchild; i++) {
2375                 struct usb_device       *udev = hdev->children[i];
2376                 int                     delta, ceiling;
2377
2378                 if (!udev)
2379                         continue;
2380
2381                 /* 100mA per-port ceiling, or 8mA for OTG ports */
2382                 if (i != (udev->bus->otg_port - 1) || hdev->parent)
2383                         ceiling = 50;
2384                 else
2385                         ceiling = 4;
2386
2387                 if (udev->actconfig)
2388                         delta = udev->actconfig->desc.bMaxPower;
2389                 else
2390                         delta = ceiling;
2391                 // dev_dbg(&udev->dev, "budgeted %dmA\n", 2 * delta);
2392                 if (delta > ceiling)
2393                         dev_warn(&udev->dev, "%dmA over %dmA budget!\n",
2394                                 2 * (delta - ceiling), 2 * ceiling);
2395                 remaining -= delta;
2396         }
2397         if (remaining < 0) {
2398                 dev_warn(hub->intfdev,
2399                         "%dmA over power budget!\n",
2400                         -2 * remaining);
2401                 remaining = 0;
2402         }
2403         return remaining;
2404 }
2405
2406 /* Handle physical or logical connection change events.
2407  * This routine is called when:
2408  *      a port connection-change occurs;
2409  *      a port enable-change occurs (often caused by EMI);
2410  *      usb_reset_device() encounters changed descriptors (as from
2411  *              a firmware download)
2412  * caller already locked the hub
2413  */
2414 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2415                                         u16 portstatus, u16 portchange)
2416 {
2417         struct usb_device *hdev = hub->hdev;
2418         struct device *hub_dev = hub->intfdev;
2419         u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2420         int status, i;
2421
2422         dev_dbg (hub_dev,
2423                 "port %d, status %04x, change %04x, %s\n",
2424                 port1, portstatus, portchange, portspeed (portstatus));
2425
2426         if (hub->has_indicators) {
2427                 set_port_led(hub, port1, HUB_LED_AUTO);
2428                 hub->indicator[port1-1] = INDICATOR_AUTO;
2429         }
2430
2431         /* Disconnect any existing devices under this port */
2432         if (hdev->children[port1-1])
2433                 usb_disconnect(&hdev->children[port1-1]);
2434         clear_bit(port1, hub->change_bits);
2435
2436 #ifdef  CONFIG_USB_OTG
2437         /* during HNP, don't repeat the debounce */
2438         if (hdev->bus->is_b_host)
2439                 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2440 #endif
2441
2442         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2443                 status = hub_port_debounce(hub, port1);
2444                 if (status < 0) {
2445                         dev_err (hub_dev,
2446                                 "connect-debounce failed, port %d disabled\n",
2447                                 port1);
2448                         goto done;
2449                 }
2450                 portstatus = status;
2451         }
2452
2453         /* Return now if nothing is connected */
2454         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2455
2456                 /* maybe switch power back on (e.g. root hub was reset) */
2457                 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
2458                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2459                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2460
2461                 if (portstatus & USB_PORT_STAT_ENABLE)
2462                         goto done;
2463                 return;
2464         }
2465
2466 #ifdef  CONFIG_USB_SUSPEND
2467         /* If something is connected, but the port is suspended, wake it up. */
2468         if (portstatus & USB_PORT_STAT_SUSPEND) {
2469                 status = hub_port_resume(hub, port1, NULL);
2470                 if (status < 0) {
2471                         dev_dbg(hub_dev,
2472                                 "can't clear suspend on port %d; %d\n",
2473                                 port1, status);
2474                         goto done;
2475                 }
2476         }
2477 #endif
2478
2479         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2480                 struct usb_device *udev;
2481
2482                 /* reallocate for each attempt, since references
2483                  * to the previous one can escape in various ways
2484                  */
2485                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2486                 if (!udev) {
2487                         dev_err (hub_dev,
2488                                 "couldn't allocate port %d usb_device\n",
2489                                 port1);
2490                         goto done;
2491                 }
2492
2493                 usb_set_device_state(udev, USB_STATE_POWERED);
2494                 udev->speed = USB_SPEED_UNKNOWN;
2495
2496                 /* set the address */
2497                 choose_address(udev);
2498                 if (udev->devnum <= 0) {
2499                         status = -ENOTCONN;     /* Don't retry */
2500                         goto loop;
2501                 }
2502
2503                 /* reset and get descriptor */
2504                 status = hub_port_init(hub, udev, port1, i);
2505                 if (status < 0)
2506                         goto loop;
2507
2508                 /* consecutive bus-powered hubs aren't reliable; they can
2509                  * violate the voltage drop budget.  if the new child has
2510                  * a "powered" LED, users should notice we didn't enable it
2511                  * (without reading syslog), even without per-port LEDs
2512                  * on the parent.
2513                  */
2514                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2515                                 && hub->power_budget) {
2516                         u16     devstat;
2517
2518                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2519                                         &devstat);
2520                         if (status < 0) {
2521                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2522                                 goto loop_disable;
2523                         }
2524                         cpu_to_le16s(&devstat);
2525                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2526                                 dev_err(&udev->dev,
2527                                         "can't connect bus-powered hub "
2528                                         "to this port\n");
2529                                 if (hub->has_indicators) {
2530                                         hub->indicator[port1-1] =
2531                                                 INDICATOR_AMBER_BLINK;
2532                                         schedule_work (&hub->leds);
2533                                 }
2534                                 status = -ENOTCONN;     /* Don't retry */
2535                                 goto loop_disable;
2536                         }
2537                 }
2538
2539                 /* check for devices running slower than they could */
2540                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2541                                 && udev->speed == USB_SPEED_FULL
2542                                 && highspeed_hubs != 0)
2543                         check_highspeed (hub, udev, port1);
2544
2545                 /* Store the parent's children[] pointer.  At this point
2546                  * udev becomes globally accessible, although presumably
2547                  * no one will look at it until hdev is unlocked.
2548                  */
2549                 down (&udev->serialize);
2550                 status = 0;
2551
2552                 /* We mustn't add new devices if the parent hub has
2553                  * been disconnected; we would race with the
2554                  * recursively_mark_NOTATTACHED() routine.
2555                  */
2556                 spin_lock_irq(&device_state_lock);
2557                 if (hdev->state == USB_STATE_NOTATTACHED)
2558                         status = -ENOTCONN;
2559                 else
2560                         hdev->children[port1-1] = udev;
2561                 spin_unlock_irq(&device_state_lock);
2562
2563                 /* Run it through the hoops (find a driver, etc) */
2564                 if (!status) {
2565                         status = usb_new_device(udev);
2566                         if (status) {
2567                                 spin_lock_irq(&device_state_lock);
2568                                 hdev->children[port1-1] = NULL;
2569                                 spin_unlock_irq(&device_state_lock);
2570                         }
2571                 }
2572
2573                 up (&udev->serialize);
2574                 if (status)
2575                         goto loop_disable;
2576
2577                 status = hub_power_remaining(hub);
2578                 if (status)
2579                         dev_dbg(hub_dev,
2580                                 "%dmA power budget left\n",
2581                                 2 * status);
2582
2583                 return;
2584
2585 loop_disable:
2586                 hub_port_disable(hub, port1, 1);
2587 loop:
2588                 ep0_reinit(udev);
2589                 release_address(udev);
2590                 usb_put_dev(udev);
2591                 if (status == -ENOTCONN)
2592                         break;
2593         }
2594
2595 done:
2596         hub_port_disable(hub, port1, 1);
2597 }
2598
2599 static void hub_events(void)
2600 {
2601         struct list_head *tmp;
2602         struct usb_device *hdev;
2603         struct usb_interface *intf;
2604         struct usb_hub *hub;
2605         struct device *hub_dev;
2606         u16 hubstatus;
2607         u16 hubchange;
2608         u16 portstatus;
2609         u16 portchange;
2610         int i, ret;
2611         int connect_change;
2612
2613         /*
2614          *  We restart the list every time to avoid a deadlock with
2615          * deleting hubs downstream from this one. This should be
2616          * safe since we delete the hub from the event list.
2617          * Not the most efficient, but avoids deadlocks.
2618          */
2619         while (1) {
2620
2621                 /* Grab the first entry at the beginning of the list */
2622                 spin_lock_irq(&hub_event_lock);
2623                 if (list_empty(&hub_event_list)) {
2624                         spin_unlock_irq(&hub_event_lock);
2625                         break;
2626                 }
2627
2628                 tmp = hub_event_list.next;
2629                 list_del_init(tmp);
2630
2631                 hub = list_entry(tmp, struct usb_hub, event_list);
2632                 hdev = hub->hdev;
2633                 intf = to_usb_interface(hub->intfdev);
2634                 hub_dev = &intf->dev;
2635
2636                 i = hub->resume_root_hub;
2637
2638                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x%s\n",
2639                                 hdev->state, hub->descriptor
2640                                         ? hub->descriptor->bNbrPorts
2641                                         : 0,
2642                                 /* NOTE: expects max 15 ports... */
2643                                 (u16) hub->change_bits[0],
2644                                 (u16) hub->event_bits[0],
2645                                 i ? ", resume root" : "");
2646
2647                 usb_get_intf(intf);
2648                 spin_unlock_irq(&hub_event_lock);
2649
2650                 /* Is this is a root hub wanting to reactivate the downstream
2651                  * ports?  If so, be sure the interface resumes even if its
2652                  * stub "device" node was never suspended.
2653                  */
2654                 if (i) {
2655                         dpm_runtime_resume(&hdev->dev);
2656                         dpm_runtime_resume(&intf->dev);
2657                 }
2658
2659                 /* Lock the device, then check to see if we were
2660                  * disconnected while waiting for the lock to succeed. */
2661                 if (locktree(hdev) < 0) {
2662                         usb_put_intf(intf);
2663                         continue;
2664                 }
2665                 if (hub != usb_get_intfdata(intf))
2666                         goto loop;
2667
2668                 /* If the hub has died, clean up after it */
2669                 if (hdev->state == USB_STATE_NOTATTACHED) {
2670                         hub_pre_reset(hub);
2671                         goto loop;
2672                 }
2673
2674                 /* If this is an inactive or suspended hub, do nothing */
2675                 if (hub->quiescing)
2676                         goto loop;
2677
2678                 if (hub->error) {
2679                         dev_dbg (hub_dev, "resetting for error %d\n",
2680                                 hub->error);
2681
2682                         ret = usb_reset_device(hdev);
2683                         if (ret) {
2684                                 dev_dbg (hub_dev,
2685                                         "error resetting hub: %d\n", ret);
2686                                 goto loop;
2687                         }
2688
2689                         hub->nerrors = 0;
2690                         hub->error = 0;
2691                 }
2692
2693                 /* deal with port status changes */
2694                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2695                         if (test_bit(i, hub->busy_bits))
2696                                 continue;
2697                         connect_change = test_bit(i, hub->change_bits);
2698                         if (!test_and_clear_bit(i, hub->event_bits) &&
2699                                         !connect_change && !hub->activating)
2700                                 continue;
2701
2702                         ret = hub_port_status(hub, i,
2703                                         &portstatus, &portchange);
2704                         if (ret < 0)
2705                                 continue;
2706
2707                         if (hub->activating && !hdev->children[i-1] &&
2708                                         (portstatus &
2709                                                 USB_PORT_STAT_CONNECTION))
2710                                 connect_change = 1;
2711
2712                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2713                                 clear_port_feature(hdev, i,
2714                                         USB_PORT_FEAT_C_CONNECTION);
2715                                 connect_change = 1;
2716                         }
2717
2718                         if (portchange & USB_PORT_STAT_C_ENABLE) {
2719                                 if (!connect_change)
2720                                         dev_dbg (hub_dev,
2721                                                 "port %d enable change, "
2722                                                 "status %08x\n",
2723                                                 i, portstatus);
2724                                 clear_port_feature(hdev, i,
2725                                         USB_PORT_FEAT_C_ENABLE);
2726
2727                                 /*
2728                                  * EM interference sometimes causes badly
2729                                  * shielded USB devices to be shutdown by
2730                                  * the hub, this hack enables them again.
2731                                  * Works at least with mouse driver.
2732                                  */
2733                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
2734                                     && !connect_change
2735                                     && hdev->children[i-1]) {
2736                                         dev_err (hub_dev,
2737                                             "port %i "
2738                                             "disabled by hub (EMI?), "
2739                                             "re-enabling...\n",
2740                                                 i);
2741                                         connect_change = 1;
2742                                 }
2743                         }
2744
2745                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2746                                 clear_port_feature(hdev, i,
2747                                         USB_PORT_FEAT_C_SUSPEND);
2748                                 if (hdev->children[i-1]) {
2749                                         ret = remote_wakeup(hdev->
2750                                                         children[i-1]);
2751                                         if (ret < 0)
2752                                                 connect_change = 1;
2753                                 } else {
2754                                         ret = -ENODEV;
2755                                         hub_port_disable(hub, i, 1);
2756                                 }
2757                                 dev_dbg (hub_dev,
2758                                         "resume on port %d, status %d\n",
2759                                         i, ret);
2760                         }
2761
2762                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2763                                 dev_err (hub_dev,
2764                                         "over-current change on port %d\n",
2765                                         i);
2766                                 clear_port_feature(hdev, i,
2767                                         USB_PORT_FEAT_C_OVER_CURRENT);
2768                                 hub_power_on(hub);
2769                         }
2770
2771                         if (portchange & USB_PORT_STAT_C_RESET) {
2772                                 dev_dbg (hub_dev,
2773                                         "reset change on port %d\n",
2774                                         i);
2775                                 clear_port_feature(hdev, i,
2776                                         USB_PORT_FEAT_C_RESET);
2777                         }
2778
2779                         if (connect_change)
2780                                 hub_port_connect_change(hub, i,
2781                                                 portstatus, portchange);
2782                 } /* end for i */
2783
2784                 /* deal with hub status changes */
2785                 if (test_and_clear_bit(0, hub->event_bits) == 0)
2786                         ;       /* do nothing */
2787                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2788                         dev_err (hub_dev, "get_hub_status failed\n");
2789                 else {
2790                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2791                                 dev_dbg (hub_dev, "power change\n");
2792                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2793                         }
2794                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
2795                                 dev_dbg (hub_dev, "overcurrent change\n");
2796                                 msleep(500);    /* Cool down */
2797                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2798                                 hub_power_on(hub);
2799                         }
2800                 }
2801
2802                 hub->activating = 0;
2803
2804                 /* If this is a root hub, tell the HCD it's okay to
2805                  * re-enable port-change interrupts now. */
2806                 if (!hdev->parent)
2807                         usb_enable_root_hub_irq(hdev->bus);
2808
2809 loop:
2810                 usb_unlock_device(hdev);
2811                 usb_put_intf(intf);
2812
2813         } /* end while (1) */
2814 }
2815
2816 static int hub_thread(void *__unused)
2817 {
2818         do {
2819                 hub_events();
2820                 wait_event_interruptible(khubd_wait,
2821                                 !list_empty(&hub_event_list) ||
2822                                 kthread_should_stop());
2823                 try_to_freeze();
2824         } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2825
2826         pr_debug("%s: khubd exiting\n", usbcore_name);
2827         return 0;
2828 }
2829
2830 static struct usb_device_id hub_id_table [] = {
2831     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2832       .bDeviceClass = USB_CLASS_HUB},
2833     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2834       .bInterfaceClass = USB_CLASS_HUB},
2835     { }                                         /* Terminating entry */
2836 };
2837
2838 MODULE_DEVICE_TABLE (usb, hub_id_table);
2839
2840 static struct usb_driver hub_driver = {
2841         .owner =        THIS_MODULE,
2842         .name =         "hub",
2843         .probe =        hub_probe,
2844         .disconnect =   hub_disconnect,
2845         .suspend =      hub_suspend,
2846         .resume =       hub_resume,
2847         .ioctl =        hub_ioctl,
2848         .id_table =     hub_id_table,
2849 };
2850
2851 int usb_hub_init(void)
2852 {
2853         if (usb_register(&hub_driver) < 0) {
2854                 printk(KERN_ERR "%s: can't register hub driver\n",
2855                         usbcore_name);
2856                 return -1;
2857         }
2858
2859         khubd_task = kthread_run(hub_thread, NULL, "khubd");
2860         if (!IS_ERR(khubd_task))
2861                 return 0;
2862
2863         /* Fall through if kernel_thread failed */
2864         usb_deregister(&hub_driver);
2865         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2866
2867         return -1;
2868 }
2869
2870 void usb_hub_cleanup(void)
2871 {
2872         kthread_stop(khubd_task);
2873
2874         /*
2875          * Hub resources are freed for us by usb_deregister. It calls
2876          * usb_driver_purge on every device which in turn calls that
2877          * devices disconnect function if it is using this driver.
2878          * The hub_disconnect function takes care of releasing the
2879          * individual hub resources. -greg
2880          */
2881         usb_deregister(&hub_driver);
2882 } /* usb_hub_cleanup() */
2883
2884 static int config_descriptors_changed(struct usb_device *udev)
2885 {
2886         unsigned                        index;
2887         unsigned                        len = 0;
2888         struct usb_config_descriptor    *buf;
2889
2890         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2891                 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2892                         len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2893         }
2894         buf = kmalloc (len, SLAB_KERNEL);
2895         if (buf == NULL) {
2896                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2897                 /* assume the worst */
2898                 return 1;
2899         }
2900         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2901                 int length;
2902                 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2903
2904                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2905                                 old_length);
2906                 if (length < old_length) {
2907                         dev_dbg(&udev->dev, "config index %d, error %d\n",
2908                                         index, length);
2909                         break;
2910                 }
2911                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2912                                 != 0) {
2913                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2914                                 index, buf->bConfigurationValue);
2915                         break;
2916                 }
2917         }
2918         kfree(buf);
2919         return index != udev->descriptor.bNumConfigurations;
2920 }
2921
2922 /**
2923  * usb_reset_device - perform a USB port reset to reinitialize a device
2924  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2925  *
2926  * WARNING - don't reset any device unless drivers for all of its
2927  * interfaces are expecting that reset!  Maybe some driver->reset()
2928  * method should eventually help ensure sufficient cooperation.
2929  *
2930  * Do a port reset, reassign the device's address, and establish its
2931  * former operating configuration.  If the reset fails, or the device's
2932  * descriptors change from their values before the reset, or the original
2933  * configuration and altsettings cannot be restored, a flag will be set
2934  * telling khubd to pretend the device has been disconnected and then
2935  * re-connected.  All drivers will be unbound, and the device will be
2936  * re-enumerated and probed all over again.
2937  *
2938  * Returns 0 if the reset succeeded, -ENODEV if the device has been
2939  * flagged for logical disconnection, or some other negative error code
2940  * if the reset wasn't even attempted.
2941  *
2942  * The caller must own the device lock.  For example, it's safe to use
2943  * this from a driver probe() routine after downloading new firmware.
2944  * For calls that might not occur during probe(), drivers should lock
2945  * the device using usb_lock_device_for_reset().
2946  */
2947 int usb_reset_device(struct usb_device *udev)
2948 {
2949         struct usb_device               *parent_hdev = udev->parent;
2950         struct usb_hub                  *parent_hub;
2951         struct usb_device_descriptor    descriptor = udev->descriptor;
2952         struct usb_hub                  *hub = NULL;
2953         int                             i, ret = 0, port1 = -1;
2954
2955         if (udev->state == USB_STATE_NOTATTACHED ||
2956                         udev->state == USB_STATE_SUSPENDED) {
2957                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2958                                 udev->state);
2959                 return -EINVAL;
2960         }
2961
2962         if (!parent_hdev) {
2963                 /* this requires hcd-specific logic; see OHCI hc_restart() */
2964                 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2965                 return -EISDIR;
2966         }
2967
2968         for (i = 0; i < parent_hdev->maxchild; i++)
2969                 if (parent_hdev->children[i] == udev) {
2970                         port1 = i + 1;
2971                         break;
2972                 }
2973
2974         if (port1 < 0) {
2975                 /* If this ever happens, it's very bad */
2976                 dev_err(&udev->dev, "Can't locate device's port!\n");
2977                 return -ENOENT;
2978         }
2979         parent_hub = hdev_to_hub(parent_hdev);
2980
2981         /* If we're resetting an active hub, take some special actions */
2982         if (udev->actconfig &&
2983                         udev->actconfig->interface[0]->dev.driver ==
2984                                 &hub_driver.driver &&
2985                         (hub = hdev_to_hub(udev)) != NULL) {
2986                 hub_pre_reset(hub);
2987         }
2988
2989         set_bit(port1, parent_hub->busy_bits);
2990         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
2991
2992                 /* ep0 maxpacket size may change; let the HCD know about it.
2993                  * Other endpoints will be handled by re-enumeration. */
2994                 ep0_reinit(udev);
2995                 ret = hub_port_init(parent_hub, udev, port1, i);
2996                 if (ret >= 0)
2997                         break;
2998         }
2999         clear_bit(port1, parent_hub->busy_bits);
3000         if (ret < 0)
3001                 goto re_enumerate;
3002
3003         /* Device might have changed firmware (DFU or similar) */
3004         if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
3005                         || config_descriptors_changed (udev)) {
3006                 dev_info(&udev->dev, "device firmware changed\n");
3007                 udev->descriptor = descriptor;  /* for disconnect() calls */
3008                 goto re_enumerate;
3009         }
3010
3011         if (!udev->actconfig)
3012                 goto done;
3013
3014         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3015                         USB_REQ_SET_CONFIGURATION, 0,
3016                         udev->actconfig->desc.bConfigurationValue, 0,
3017                         NULL, 0, USB_CTRL_SET_TIMEOUT);
3018         if (ret < 0) {
3019                 dev_err(&udev->dev,
3020                         "can't restore configuration #%d (error=%d)\n",
3021                         udev->actconfig->desc.bConfigurationValue, ret);
3022                 goto re_enumerate;
3023         }
3024         usb_set_device_state(udev, USB_STATE_CONFIGURED);
3025
3026         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3027                 struct usb_interface *intf = udev->actconfig->interface[i];
3028                 struct usb_interface_descriptor *desc;
3029
3030                 /* set_interface resets host side toggle even
3031                  * for altsetting zero.  the interface may have no driver.
3032                  */
3033                 desc = &intf->cur_altsetting->desc;
3034                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3035                         desc->bAlternateSetting);
3036                 if (ret < 0) {
3037                         dev_err(&udev->dev, "failed to restore interface %d "
3038                                 "altsetting %d (error=%d)\n",
3039                                 desc->bInterfaceNumber,
3040                                 desc->bAlternateSetting,
3041                                 ret);
3042                         goto re_enumerate;
3043                 }
3044         }
3045
3046 done:
3047         if (hub)
3048                 hub_post_reset(hub);
3049         return 0;
3050
3051 re_enumerate:
3052         hub_port_logical_disconnect(parent_hub, port1);
3053         return -ENODEV;
3054 }