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
 440         /* if hub supports power switching, enable power on each port */
 441         if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_LPSM) < 2) {
 442                 dev_dbg(hub->intfdev, "enabling power on all ports\n");
 443                 for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
 444                         set_port_feature(hub->hdev, port1,
 445                                         USB_PORT_FEAT_POWER);
 446         }
 447
 448         /* Wait at least 100 msec for power to become stable */
 449         msleep(max(pgood_delay, (unsigned) 100));
 450 }
 451
 452 static void hub_quiesce(struct usb_hub *hub)
 453 {
 454         /* stop khubd and related activity */
 455         hub->quiescing = 1;
 456         usb_kill_urb(hub->urb);
 457         if (hub->has_indicators)
 458                 cancel_delayed_work(&hub->leds);
 459         if (hub->has_indicators || hub->tt.hub)
 460                 flush_scheduled_work();
 461 }
 462
 463 static void hub_activate(struct usb_hub *hub)
 464 {
 465         int     status;
 466
 467         hub->quiescing = 0;
 468         hub->activating = 1;
 469         status = usb_submit_urb(hub->urb, GFP_NOIO);
 470         if (status < 0)
 471                 dev_err(hub->intfdev, "activate --> %d\n", status);
 472         if (hub->has_indicators && blinkenlights)
 473                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 474
 475         /* scan all ports ASAP */
 476         kick_khubd(hub);
 477 }
 478
 479 static int hub_hub_status(struct usb_hub *hub,
 480                 u16 *status, u16 *change)
 481 {
 482         int ret;
 483
 484         ret = get_hub_status(hub->hdev, &hub->status->hub);
 485         if (ret < 0)
 486                 dev_err (hub->intfdev,
 487                         "%s failed (err = %d)\n", __FUNCTION__, ret);
 488         else {
 489                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
 490                 *change = le16_to_cpu(hub->status->hub.wHubChange);
 491                 ret = 0;
 492         }
 493         return ret;
 494 }
 495
 496 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
 497 {
 498         struct usb_device *hdev = hub->hdev;
 499         int ret;
 500
 501         if (hdev->children[port1-1] && set_state) {
 502                 usb_set_device_state(hdev->children[port1-1],
 503                                 USB_STATE_NOTATTACHED);
 504         }
 505         ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
 506         if (ret)
 507                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
 508                         port1, ret);
 509
 510         return ret;
 511 }
 512
 513 static int hub_configure(struct usb_hub *hub,
 514         struct usb_endpoint_descriptor *endpoint)
 515 {
 516         struct usb_device *hdev = hub->hdev;
 517         struct device *hub_dev = hub->intfdev;
 518         u16 hubstatus, hubchange;
 519         unsigned int pipe;
 520         int maxp, ret;
 521         char *message;
 522
 523         hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
 524                         &hub->buffer_dma);
 525         if (!hub->buffer) {
 526                 message = "can't allocate hub irq buffer";
 527                 ret = -ENOMEM;
 528                 goto fail;
 529         }
 530
 531         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
 532         if (!hub->status) {
 533                 message = "can't kmalloc hub status buffer";
 534                 ret = -ENOMEM;
 535                 goto fail;
 536         }
 537
 538         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
 539         if (!hub->descriptor) {
 540                 message = "can't kmalloc hub descriptor";
 541                 ret = -ENOMEM;
 542                 goto fail;
 543         }
 544
 545         /* Request the entire hub descriptor.
 546          * hub->descriptor can handle USB_MAXCHILDREN ports,
 547          * but the hub can/will return fewer bytes here.
 548          */
 549         ret = get_hub_descriptor(hdev, hub->descriptor,
 550                         sizeof(*hub->descriptor));
 551         if (ret < 0) {
 552                 message = "can't read hub descriptor";
 553                 goto fail;
 554         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
 555                 message = "hub has too many ports!";
 556                 ret = -ENODEV;
 557                 goto fail;
 558         }
 559
 560         hdev->maxchild = hub->descriptor->bNbrPorts;
 561         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
 562                 (hdev->maxchild == 1) ? "" : "s");
 563
 564         le16_to_cpus(&hub->descriptor->wHubCharacteristics);
 565
 566         if (hub->descriptor->wHubCharacteristics & HUB_CHAR_COMPOUND) {
 567                 int     i;
 568                 char    portstr [USB_MAXCHILDREN + 1];
 569
 570                 for (i = 0; i < hdev->maxchild; i++)
 571                         portstr[i] = hub->descriptor->DeviceRemovable
 572                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
 573                                 ? 'F' : 'R';
 574                 portstr[hdev->maxchild] = 0;
 575                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
 576         } else
 577                 dev_dbg(hub_dev, "standalone hub\n");
 578
 579         switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_LPSM) {
 580                 case 0x00:
 581                         dev_dbg(hub_dev, "ganged power switching\n");
 582                         break;
 583                 case 0x01:
 584                         dev_dbg(hub_dev, "individual port power switching\n");
 585                         break;
 586                 case 0x02:
 587                 case 0x03:
 588                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
 589                         break;
 590         }
 591
 592         switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) {
 593                 case 0x00:
 594                         dev_dbg(hub_dev, "global over-current protection\n");
 595                         break;
 596                 case 0x08:
 597                         dev_dbg(hub_dev, "individual port over-current protection\n");
 598                         break;
 599                 case 0x10:
 600                 case 0x18:
 601                         dev_dbg(hub_dev, "no over-current protection\n");
 602                         break;
 603         }
 604
 605         spin_lock_init (&hub->tt.lock);
 606         INIT_LIST_HEAD (&hub->tt.clear_list);
 607         INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub);
 608         switch (hdev->descriptor.bDeviceProtocol) {
 609                 case 0:
 610                         break;
 611                 case 1:
 612                         dev_dbg(hub_dev, "Single TT\n");
 613                         hub->tt.hub = hdev;
 614                         break;
 615                 case 2:
 616                         ret = usb_set_interface(hdev, 0, 1);
 617                         if (ret == 0) {
 618                                 dev_dbg(hub_dev, "TT per port\n");
 619                                 hub->tt.multi = 1;
 620                         } else
 621                                 dev_err(hub_dev, "Using single TT (err %d)\n",
 622                                         ret);
 623                         hub->tt.hub = hdev;
 624                         break;
 625                 default:
 626                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
 627                                 hdev->descriptor.bDeviceProtocol);
 628                         break;
 629         }
 630
 631         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
 632         switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_TTTT) {
 633                 case HUB_TTTT_8_BITS:
 634                         if (hdev->descriptor.bDeviceProtocol != 0) {
 635                                 hub->tt.think_time = 666;
 636                                 dev_dbg(hub_dev, "TT requires at most %d "
 637                                                 "FS bit times (%d ns)\n",
 638                                         8, hub->tt.think_time);
 639                         }
 640                         break;
 641                 case HUB_TTTT_16_BITS:
 642                         hub->tt.think_time = 666 * 2;
 643                         dev_dbg(hub_dev, "TT requires at most %d "
 644                                         "FS bit times (%d ns)\n",
 645                                 16, hub->tt.think_time);
 646                         break;
 647                 case HUB_TTTT_24_BITS:
 648                         hub->tt.think_time = 666 * 3;
 649                         dev_dbg(hub_dev, "TT requires at most %d "
 650                                         "FS bit times (%d ns)\n",
 651                                 24, hub->tt.think_time);
 652                         break;
 653                 case HUB_TTTT_32_BITS:
 654                         hub->tt.think_time = 666 * 4;
 655                         dev_dbg(hub_dev, "TT requires at most %d "
 656                                         "FS bit times (%d ns)\n",
 657                                 32, hub->tt.think_time);
 658                         break;
 659         }
 660
 661         /* probe() zeroes hub->indicator[] */
 662         if (hub->descriptor->wHubCharacteristics & HUB_CHAR_PORTIND) {
 663                 hub->has_indicators = 1;
 664                 dev_dbg(hub_dev, "Port indicators are supported\n");
 665         }
 666
 667         dev_dbg(hub_dev, "power on to power good time: %dms\n",
 668                 hub->descriptor->bPwrOn2PwrGood * 2);
 669
 670         /* power budgeting mostly matters with bus-powered hubs,
 671          * and battery-powered root hubs (may provide just 8 mA).
 672          */
 673         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
 674         if (ret < 0) {
 675                 message = "can't get hub status";
 676                 goto fail;
 677         }
 678         le16_to_cpus(&hubstatus);
 679         if (hdev == hdev->bus->root_hub) {
 680                 struct usb_hcd *hcd =
 681                                 container_of(hdev->bus, struct usb_hcd, self);
 682
 683                 hub->power_budget = min(500u, hcd->power_budget) / 2;
 684         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
 685                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
 686                         hub->descriptor->bHubContrCurrent);
 687                 hub->power_budget = (501 - hub->descriptor->bHubContrCurrent)
 688                                         / 2;
 689         }
 690         if (hub->power_budget)
 691                 dev_dbg(hub_dev, "%dmA bus power budget for children\n",
 692                         hub->power_budget * 2);
 693
 694
 695         ret = hub_hub_status(hub, &hubstatus, &hubchange);
 696         if (ret < 0) {
 697                 message = "can't get hub status";
 698                 goto fail;
 699         }
 700
 701         /* local power status reports aren't always correct */
 702         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
 703                 dev_dbg(hub_dev, "local power source is %s\n",
 704                         (hubstatus & HUB_STATUS_LOCAL_POWER)
 705                         ? "lost (inactive)" : "good");
 706
 707         if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) == 0)
 708                 dev_dbg(hub_dev, "%sover-current condition exists\n",
 709                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
 710
 711         /* set up the interrupt endpoint */
 712         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
 713         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
 714
 715         if (maxp > sizeof(*hub->buffer))
 716                 maxp = sizeof(*hub->buffer);
 717
 718         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
 719         if (!hub->urb) {
 720                 message = "couldn't allocate interrupt urb";
 721                 ret = -ENOMEM;
 722                 goto fail;
 723         }
 724
 725         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
 726                 hub, endpoint->bInterval);
 727         hub->urb->transfer_dma = hub->buffer_dma;
 728         hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 729
 730         /* maybe cycle the hub leds */
 731         if (hub->has_indicators && blinkenlights)
 732                 hub->indicator [0] = INDICATOR_CYCLE;
 733
 734         hub_power_on(hub);
 735         hub_activate(hub);
 736         return 0;
 737
 738 fail:
 739         dev_err (hub_dev, "config failed, %s (err %d)\n",
 740                         message, ret);
 741         /* hub_disconnect() frees urb and descriptor */
 742         return ret;
 743 }
 744
 745 static unsigned highspeed_hubs;
 746
 747 /* Called after the hub driver is unbound from a hub with children */
 748 static void hub_remove_children_work(void *__hub)
 749 {
 750         struct usb_hub          *hub = __hub;
 751         struct usb_device       *hdev = hub->hdev;
 752         int                     i;
 753
 754         kfree(hub);
 755
 756         usb_lock_device(hdev);
 757         for (i = 0; i < hdev->maxchild; ++i) {
 758                 if (hdev->children[i])
 759                         usb_disconnect(&hdev->children[i]);
 760         }
 761         usb_unlock_device(hdev);
 762         usb_put_dev(hdev);
 763 }
 764
 765 static void hub_disconnect(struct usb_interface *intf)
 766 {
 767         struct usb_hub *hub = usb_get_intfdata (intf);
 768         struct usb_device *hdev;
 769         int n, port1;
 770
 771         usb_set_intfdata (intf, NULL);
 772         hdev = hub->hdev;
 773
 774         if (hdev->speed == USB_SPEED_HIGH)
 775                 highspeed_hubs--;
 776
 777         hub_quiesce(hub);
 778         usb_free_urb(hub->urb);
 779         hub->urb = NULL;
 780
 781         spin_lock_irq(&hub_event_lock);
 782         list_del_init(&hub->event_list);
 783         spin_unlock_irq(&hub_event_lock);
 784
 785         kfree(hub->descriptor);
 786         hub->descriptor = NULL;
 787
 788         kfree(hub->status);
 789         hub->status = NULL;
 790
 791         if (hub->buffer) {
 792                 usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
 793                                 hub->buffer_dma);
 794                 hub->buffer = NULL;
 795         }
 796
 797         /* If there are any children then this is an unbind only, not a
 798          * physical disconnection.  The active ports must be disabled
 799          * and later on we must call usb_disconnect().  We can't call
 800          * it now because we may not hold the hub's device lock.
 801          */
 802         n = 0;
 803         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
 804                 if (hdev->children[port1 - 1]) {
 805                         ++n;
 806                         hub_port_disable(hub, port1, 1);
 807                 }
 808         }
 809
 810         if (n == 0)
 811                 kfree(hub);
 812         else {
 813                 /* Reuse the hub->leds work_struct for our own purposes */
 814                 INIT_WORK(&hub->leds, hub_remove_children_work, hub);
 815                 schedule_work(&hub->leds);
 816                 usb_get_dev(hdev);
 817         }
 818 }
 819
 820 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
 821 {
 822         struct usb_host_interface *desc;
 823         struct usb_endpoint_descriptor *endpoint;
 824         struct usb_device *hdev;
 825         struct usb_hub *hub;
 826
 827         desc = intf->cur_altsetting;
 828         hdev = interface_to_usbdev(intf);
 829
 830         /* Some hubs have a subclass of 1, which AFAICT according to the */
 831         /*  specs is not defined, but it works */
 832         if ((desc->desc.bInterfaceSubClass != 0) &&
 833             (desc->desc.bInterfaceSubClass != 1)) {
 834 descriptor_error:
 835                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
 836                 return -EIO;
 837         }
 838
 839         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
 840         if (desc->desc.bNumEndpoints != 1)
 841                 goto descriptor_error;
 842
 843         endpoint = &desc->endpoint[0].desc;
 844
 845         /* Output endpoint? Curiouser and curiouser.. */
 846         if (!(endpoint->bEndpointAddress & USB_DIR_IN))
 847                 goto descriptor_error;
 848
 849         /* If it's not an interrupt endpoint, we'd better punt! */
 850         if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
 851                         != USB_ENDPOINT_XFER_INT)
 852                 goto descriptor_error;
 853
 854         /* We found a hub */
 855         dev_info (&intf->dev, "USB hub found\n");
 856
 857         hub = kmalloc(sizeof(*hub), GFP_KERNEL);
 858         if (!hub) {
 859                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
 860                 return -ENOMEM;
 861         }
 862
 863         memset(hub, 0, sizeof(*hub));
 864
 865         INIT_LIST_HEAD(&hub->event_list);
 866         hub->intfdev = &intf->dev;
 867         hub->hdev = hdev;
 868         INIT_WORK(&hub->leds, led_work, hub);
 869
 870         usb_set_intfdata (intf, hub);
 871
 872         if (hdev->speed == USB_SPEED_HIGH)
 873                 highspeed_hubs++;
 874
 875         if (hub_configure(hub, endpoint) >= 0)
 876                 return 0;
 877
 878         hub_disconnect (intf);
 879         return -ENODEV;
 880 }
 881
 882 static int
 883 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
 884 {
 885         struct usb_device *hdev = interface_to_usbdev (intf);
 886
 887         /* assert ifno == 0 (part of hub spec) */
 888         switch (code) {
 889         case USBDEVFS_HUB_PORTINFO: {
 890                 struct usbdevfs_hub_portinfo *info = user_data;
 891                 int i;
 892
 893                 spin_lock_irq(&device_state_lock);
 894                 if (hdev->devnum <= 0)
 895                         info->nports = 0;
 896                 else {
 897                         info->nports = hdev->maxchild;
 898                         for (i = 0; i < info->nports; i++) {
 899                                 if (hdev->children[i] == NULL)
 900                                         info->port[i] = 0;
 901                                 else
 902                                         info->port[i] =
 903                                                 hdev->children[i]->devnum;
 904                         }
 905                 }
 906                 spin_unlock_irq(&device_state_lock);
 907
 908                 return info->nports + 1;
 909                 }
 910
 911         default:
 912                 return -ENOSYS;
 913         }
 914 }
 915
 916 /* caller has locked the hub device */
 917 static void hub_pre_reset(struct usb_hub *hub)
 918 {
 919         struct usb_device *hdev = hub->hdev;
 920         int i;
 921
 922         for (i = 0; i < hdev->maxchild; ++i) {
 923                 if (hdev->children[i])
 924                         usb_disconnect(&hdev->children[i]);
 925         }
 926         hub_quiesce(hub);
 927 }
 928
 929 /* caller has locked the hub device */
 930 static void hub_post_reset(struct usb_hub *hub)
 931 {
 932         hub_activate(hub);
 933         hub_power_on(hub);
 934 }
 935
 936
 937 /* grab device/port lock, returning index of that port (zero based).
 938  * protects the upstream link used by this device from concurrent
 939  * tree operations like suspend, resume, reset, and disconnect, which
 940  * apply to everything downstream of a given port.
 941  */
 942 static int locktree(struct usb_device *udev)
 943 {
 944         int                     t;
 945         struct usb_device       *hdev;
 946
 947         if (!udev)
 948                 return -ENODEV;
 949
 950         /* root hub is always the first lock in the series */
 951         hdev = udev->parent;
 952         if (!hdev) {
 953                 usb_lock_device(udev);
 954                 return 0;
 955         }
 956
 957         /* on the path from root to us, lock everything from
 958          * top down, dropping parent locks when not needed
 959          */
 960         t = locktree(hdev);
 961         if (t < 0)
 962                 return t;
 963         for (t = 0; t < hdev->maxchild; t++) {
 964                 if (hdev->children[t] == udev) {
 965                         /* everything is fail-fast once disconnect
 966                          * processing starts
 967                          */
 968                         if (udev->state == USB_STATE_NOTATTACHED)
 969                                 break;
 970
 971                         /* when everyone grabs locks top->bottom,
 972                          * non-overlapping work may be concurrent
 973                          */
 974                         down(&udev->serialize);
 975                         up(&hdev->serialize);
 976                         return t + 1;
 977                 }
 978         }
 979         usb_unlock_device(hdev);
 980         return -ENODEV;
 981 }
 982
 983 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
 984 {
 985         int i;
 986
 987         for (i = 0; i < udev->maxchild; ++i) {
 988                 if (udev->children[i])
 989                         recursively_mark_NOTATTACHED(udev->children[i]);
 990         }
 991         udev->state = USB_STATE_NOTATTACHED;
 992 }
 993
 994 /**
 995  * usb_set_device_state - change a device's current state (usbcore, hcds)
 996  * @udev: pointer to device whose state should be changed
 997  * @new_state: new state value to be stored
 998  *
 999  * udev->state is _not_ fully protected by the device lock.  Although
1000  * most transitions are made only while holding the lock, the state can
1001  * can change to USB_STATE_NOTATTACHED at almost any time.  This
1002  * is so that devices can be marked as disconnected as soon as possible,
1003  * without having to wait for any semaphores to be released.  As a result,
1004  * all changes to any device's state must be protected by the
1005  * device_state_lock spinlock.
1006  *
1007  * Once a device has been added to the device tree, all changes to its state
1008  * should be made using this routine.  The state should _not_ be set directly.
1009  *
1010  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1011  * Otherwise udev->state is set to new_state, and if new_state is
1012  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1013  * to USB_STATE_NOTATTACHED.
1014  */
1015 void usb_set_device_state(struct usb_device *udev,
1016                 enum usb_device_state new_state)
1017 {
1018         unsigned long flags;
1019
1020         spin_lock_irqsave(&device_state_lock, flags);
1021         if (udev->state == USB_STATE_NOTATTACHED)
1022                 ;       /* do nothing */
1023         else if (new_state != USB_STATE_NOTATTACHED)
1024                 udev->state = new_state;
1025         else
1026                 recursively_mark_NOTATTACHED(udev);
1027         spin_unlock_irqrestore(&device_state_lock, flags);
1028 }
1029 EXPORT_SYMBOL(usb_set_device_state);
1030
1031
1032 static void choose_address(struct usb_device *udev)
1033 {
1034         int             devnum;
1035         struct usb_bus  *bus = udev->bus;
1036
1037         /* If khubd ever becomes multithreaded, this will need a lock */
1038
1039         /* Try to allocate the next devnum beginning at bus->devnum_next. */
1040         devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1041                         bus->devnum_next);
1042         if (devnum >= 128)
1043                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1044
1045         bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1046
1047         if (devnum < 128) {
1048                 set_bit(devnum, bus->devmap.devicemap);
1049                 udev->devnum = devnum;
1050         }
1051 }
1052
1053 static void release_address(struct usb_device *udev)
1054 {
1055         if (udev->devnum > 0) {
1056                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1057                 udev->devnum = -1;
1058         }
1059 }
1060
1061 /**
1062  * usb_disconnect - disconnect a device (usbcore-internal)
1063  * @pdev: pointer to device being disconnected
1064  * Context: !in_interrupt ()
1065  *
1066  * Something got disconnected. Get rid of it and all of its children.
1067  *
1068  * If *pdev is a normal device then the parent hub must already be locked.
1069  * If *pdev is a root hub then this routine will acquire the
1070  * usb_bus_list_lock on behalf of the caller.
1071  *
1072  * Only hub drivers (including virtual root hub drivers for host
1073  * controllers) should ever call this.
1074  *
1075  * This call is synchronous, and may not be used in an interrupt context.
1076  */
1077 void usb_disconnect(struct usb_device **pdev)
1078 {
1079         struct usb_device       *udev = *pdev;
1080         int                     i;
1081
1082         if (!udev) {
1083                 pr_debug ("%s nodev\n", __FUNCTION__);
1084                 return;
1085         }
1086
1087         /* mark the device as inactive, so any further urb submissions for
1088          * this device (and any of its children) will fail immediately.
1089          * this quiesces everyting except pending urbs.
1090          */
1091         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1092
1093         /* lock the bus list on behalf of HCDs unregistering their root hubs */
1094         if (!udev->parent) {
1095                 down(&usb_bus_list_lock);
1096                 usb_lock_device(udev);
1097         } else
1098                 down(&udev->serialize);
1099
1100         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1101
1102         /* Free up all the children before we remove this device */
1103         for (i = 0; i < USB_MAXCHILDREN; i++) {
1104                 if (udev->children[i])
1105                         usb_disconnect(&udev->children[i]);
1106         }
1107
1108         /* deallocate hcd/hardware state ... nuking all pending urbs and
1109          * cleaning up all state associated with the current configuration
1110          * so that the hardware is now fully quiesced.
1111          */
1112         usb_disable_device(udev, 0);
1113
1114         /* Free the device number, remove the /proc/bus/usb entry and
1115          * the sysfs attributes, and delete the parent's children[]
1116          * (or root_hub) pointer.
1117          */
1118         dev_dbg (&udev->dev, "unregistering device\n");
1119         release_address(udev);
1120         usbfs_remove_device(udev);
1121         usbdev_remove(udev);
1122         usb_remove_sysfs_dev_files(udev);
1123
1124         /* Avoid races with recursively_mark_NOTATTACHED() */
1125         spin_lock_irq(&device_state_lock);
1126         *pdev = NULL;
1127         spin_unlock_irq(&device_state_lock);
1128
1129         if (!udev->parent) {
1130                 usb_unlock_device(udev);
1131                 up(&usb_bus_list_lock);
1132         } else
1133                 up(&udev->serialize);
1134
1135         device_unregister(&udev->dev);
1136 }
1137
1138 static int choose_configuration(struct usb_device *udev)
1139 {
1140         int c, i;
1141
1142         /* NOTE: this should interact with hub power budgeting */
1143
1144         c = udev->config[0].desc.bConfigurationValue;
1145         if (udev->descriptor.bNumConfigurations != 1) {
1146                 for (i = 0; i < udev->descriptor.bNumConfigurations; i++) {
1147                         struct usb_interface_descriptor *desc;
1148
1149                         /* heuristic:  Linux is more likely to have class
1150                          * drivers, so avoid vendor-specific interfaces.
1151                          */
1152                         desc = &udev->config[i].intf_cache[0]
1153                                         ->altsetting->desc;
1154                         if (desc->bInterfaceClass == USB_CLASS_VENDOR_SPEC)
1155                                 continue;
1156                         /* COMM/2/all is CDC ACM, except 0xff is MSFT RNDIS.
1157                          * MSFT needs this to be the first config; never use
1158                          * it as the default unless Linux has host-side RNDIS.
1159                          * A second config would ideally be CDC-Ethernet, but
1160                          * may instead be the "vendor specific" CDC subset
1161                          * long used by ARM Linux for sa1100 or pxa255.
1162                          */
1163                         if (desc->bInterfaceClass == USB_CLASS_COMM
1164                                         && desc->bInterfaceSubClass == 2
1165                                         && desc->bInterfaceProtocol == 0xff) {
1166                                 c = udev->config[1].desc.bConfigurationValue;
1167                                 continue;
1168                         }
1169                         c = udev->config[i].desc.bConfigurationValue;
1170                         break;
1171                 }
1172                 dev_info(&udev->dev,
1173                         "configuration #%d chosen from %d choices\n",
1174                         c, udev->descriptor.bNumConfigurations);
1175         }
1176         return c;
1177 }
1178
1179 #ifdef DEBUG
1180 static void show_string(struct usb_device *udev, char *id, char *string)
1181 {
1182         if (!string)
1183                 return;
1184         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1185 }
1186
1187 #else
1188 static inline void show_string(struct usb_device *udev, char *id, char *string)
1189 {}
1190 #endif
1191
1192 static void get_string(struct usb_device *udev, char **string, int index)
1193 {
1194         char *buf;
1195
1196         if (!index)
1197                 return;
1198         buf = kmalloc(256, GFP_KERNEL);
1199         if (!buf)
1200                 return;
1201         if (usb_string(udev, index, buf, 256) > 0)
1202                 *string = buf;
1203         else
1204                 kfree(buf);
1205 }
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         get_string(udev, &udev->product, udev->descriptor.iProduct);
1246         get_string(udev, &udev->manufacturer, udev->descriptor.iManufacturer);
1247         get_string(udev, &udev->serial, udev->descriptor.iSerialNumber);
1248
1249         /* Tell the world! */
1250         dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1251                         "SerialNumber=%d\n",
1252                         udev->descriptor.iManufacturer,
1253                         udev->descriptor.iProduct,
1254                         udev->descriptor.iSerialNumber);
1255         show_string(udev, "Product", udev->product);
1256         show_string(udev, "Manufacturer", udev->manufacturer);
1257         show_string(udev, "SerialNumber", udev->serial);
1258
1259 #ifdef  CONFIG_USB_OTG
1260         /*
1261          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1262          * to wake us after we've powered off VBUS; and HNP, switching roles
1263          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1264          */
1265         if (!udev->bus->is_b_host
1266                         && udev->config
1267                         && udev->parent == udev->bus->root_hub) {
1268                 struct usb_otg_descriptor       *desc = 0;
1269                 struct usb_bus                  *bus = udev->bus;
1270
1271                 /* descriptor may appear anywhere in config */
1272                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1273                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1274                                         USB_DT_OTG, (void **) &desc) == 0) {
1275                         if (desc->bmAttributes & USB_OTG_HNP) {
1276                                 unsigned                port1;
1277                                 struct usb_device       *root = udev->parent;
1278
1279                                 for (port1 = 1; port1 <= root->maxchild;
1280                                                 port1++) {
1281                                         if (root->children[port1-1] == udev)
1282                                                 break;
1283                                 }
1284
1285                                 dev_info(&udev->dev,
1286                                         "Dual-Role OTG device on %sHNP port\n",
1287                                         (port1 == bus->otg_port)
1288                                                 ? "" : "non-");
1289
1290                                 /* enable HNP before suspend, it's simpler */
1291                                 if (port1 == bus->otg_port)
1292                                         bus->b_hnp_enable = 1;
1293                                 err = usb_control_msg(udev,
1294                                         usb_sndctrlpipe(udev, 0),
1295                                         USB_REQ_SET_FEATURE, 0,
1296                                         bus->b_hnp_enable
1297                                                 ? USB_DEVICE_B_HNP_ENABLE
1298                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1299                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1300                                 if (err < 0) {
1301                                         /* OTG MESSAGE: report errors here,
1302                                          * customize to match your product.
1303                                          */
1304                                         dev_info(&udev->dev,
1305                                                 "can't set HNP mode; %d\n",
1306                                                 err);
1307                                         bus->b_hnp_enable = 0;
1308                                 }
1309                         }
1310                 }
1311         }
1312
1313         if (!is_targeted(udev)) {
1314
1315                 /* Maybe it can talk to us, though we can't talk to it.
1316                  * (Includes HNP test device.)
1317                  */
1318                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1319                         static int __usb_suspend_device (struct usb_device *,
1320                                                 int port1, pm_message_t state);
1321                         err = __usb_suspend_device(udev,
1322                                         udev->bus->otg_port,
1323                                         PMSG_SUSPEND);
1324                         if (err < 0)
1325                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1326                 }
1327                 err = -ENODEV;
1328                 goto fail;
1329         }
1330 #endif
1331
1332         /* put device-specific files into sysfs */
1333         err = device_add (&udev->dev);
1334         if (err) {
1335                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1336                 goto fail;
1337         }
1338         usb_create_sysfs_dev_files (udev);
1339
1340         /* choose and set the configuration. that registers the interfaces
1341          * with the driver core, and lets usb device drivers bind to them.
1342          */
1343         c = choose_configuration(udev);
1344         if (c < 0)
1345                 dev_warn(&udev->dev,
1346                                 "can't choose an initial configuration\n");
1347         else {
1348                 err = usb_set_configuration(udev, c);
1349                 if (err) {
1350                         dev_err(&udev->dev, "can't set config #%d, error %d\n",
1351                                         c, err);
1352                         usb_remove_sysfs_dev_files(udev);
1353                         device_del(&udev->dev);
1354                         goto fail;
1355                 }
1356         }
1357
1358         /* USB device state == configured ... usable */
1359
1360         /* add a /proc/bus/usb entry */
1361         usbdev_add(udev);
1362         usbfs_add_device(udev);
1363         return 0;
1364
1365 fail:
1366         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1367         return err;
1368 }
1369
1370
1371 static int hub_port_status(struct usb_hub *hub, int port1,
1372                                u16 *status, u16 *change)
1373 {
1374         int ret;
1375
1376         ret = get_port_status(hub->hdev, port1, &hub->status->port);
1377         if (ret < 0)
1378                 dev_err (hub->intfdev,
1379                         "%s failed (err = %d)\n", __FUNCTION__, ret);
1380         else {
1381                 *status = le16_to_cpu(hub->status->port.wPortStatus);
1382                 *change = le16_to_cpu(hub->status->port.wPortChange);
1383                 ret = 0;
1384         }
1385         return ret;
1386 }
1387
1388 #define PORT_RESET_TRIES        5
1389 #define SET_ADDRESS_TRIES       2
1390 #define GET_DESCRIPTOR_TRIES    2
1391 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1392 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1393
1394 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1395 #define HUB_SHORT_RESET_TIME    10
1396 #define HUB_LONG_RESET_TIME     200
1397 #define HUB_RESET_TIMEOUT       500
1398
1399 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1400                                 struct usb_device *udev, unsigned int delay)
1401 {
1402         int delay_time, ret;
1403         u16 portstatus;
1404         u16 portchange;
1405
1406         for (delay_time = 0;
1407                         delay_time < HUB_RESET_TIMEOUT;
1408                         delay_time += delay) {
1409                 /* wait to give the device a chance to reset */
1410                 msleep(delay);
1411
1412                 /* read and decode port status */
1413                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1414                 if (ret < 0)
1415                         return ret;
1416
1417                 /* Device went away? */
1418                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1419                         return -ENOTCONN;
1420
1421                 /* bomb out completely if something weird happened */
1422                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1423                         return -EINVAL;
1424
1425                 /* if we`ve finished resetting, then break out of the loop */
1426                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1427                     (portstatus & USB_PORT_STAT_ENABLE)) {
1428                         if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1429                                 udev->speed = USB_SPEED_HIGH;
1430                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1431                                 udev->speed = USB_SPEED_LOW;
1432                         else
1433                                 udev->speed = USB_SPEED_FULL;
1434                         return 0;
1435                 }
1436
1437                 /* switch to the long delay after two short delay failures */
1438                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1439                         delay = HUB_LONG_RESET_TIME;
1440
1441                 dev_dbg (hub->intfdev,
1442                         "port %d not reset yet, waiting %dms\n",
1443                         port1, delay);
1444         }
1445
1446         return -EBUSY;
1447 }
1448
1449 static int hub_port_reset(struct usb_hub *hub, int port1,
1450                                 struct usb_device *udev, unsigned int delay)
1451 {
1452         int i, status;
1453
1454         /* Reset the port */
1455         for (i = 0; i < PORT_RESET_TRIES; i++) {
1456                 status = set_port_feature(hub->hdev,
1457                                 port1, USB_PORT_FEAT_RESET);
1458                 if (status)
1459                         dev_err(hub->intfdev,
1460                                         "cannot reset port %d (err = %d)\n",
1461                                         port1, status);
1462                 else {
1463                         status = hub_port_wait_reset(hub, port1, udev, delay);
1464                         if (status && status != -ENOTCONN)
1465                                 dev_dbg(hub->intfdev,
1466                                                 "port_wait_reset: err = %d\n",
1467                                                 status);
1468                 }
1469
1470                 /* return on disconnect or reset */
1471                 switch (status) {
1472                 case 0:
1473                         /* TRSTRCY = 10 ms; plus some extra */
1474                         msleep(10 + 40);
1475                         /* FALL THROUGH */
1476                 case -ENOTCONN:
1477                 case -ENODEV:
1478                         clear_port_feature(hub->hdev,
1479                                 port1, USB_PORT_FEAT_C_RESET);
1480                         /* FIXME need disconnect() for NOTATTACHED device */
1481                         usb_set_device_state(udev, status
1482                                         ? USB_STATE_NOTATTACHED
1483                                         : USB_STATE_DEFAULT);
1484                         return status;
1485                 }
1486
1487                 dev_dbg (hub->intfdev,
1488                         "port %d not enabled, trying reset again...\n",
1489                         port1);
1490                 delay = HUB_LONG_RESET_TIME;
1491         }
1492
1493         dev_err (hub->intfdev,
1494                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1495                 port1);
1496
1497         return status;
1498 }
1499
1500 /*
1501  * Disable a port and mark a logical connnect-change event, so that some
1502  * time later khubd will disconnect() any existing usb_device on the port
1503  * and will re-enumerate if there actually is a device attached.
1504  */
1505 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1506 {
1507         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1508         hub_port_disable(hub, port1, 1);
1509
1510         /* FIXME let caller ask to power down the port:
1511          *  - some devices won't enumerate without a VBUS power cycle
1512          *  - SRP saves power that way
1513          *  - usb_suspend_device(dev, PMSG_SUSPEND)
1514          * That's easy if this hub can switch power per-port, and
1515          * khubd reactivates the port later (timer, SRP, etc).
1516          * Powerdown must be optional, because of reset/DFU.
1517          */
1518
1519         set_bit(port1, hub->change_bits);
1520         kick_khubd(hub);
1521 }
1522
1523
1524 #ifdef  CONFIG_USB_SUSPEND
1525
1526 /*
1527  * Selective port suspend reduces power; most suspended devices draw
1528  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1529  * All devices below the suspended port are also suspended.
1530  *
1531  * Devices leave suspend state when the host wakes them up.  Some devices
1532  * also support "remote wakeup", where the device can activate the USB
1533  * tree above them to deliver data, such as a keypress or packet.  In
1534  * some cases, this wakes the USB host.
1535  */
1536 static int hub_port_suspend(struct usb_hub *hub, int port1,
1537                 struct usb_device *udev)
1538 {
1539         int     status;
1540
1541         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1542
1543         /* enable remote wakeup when appropriate; this lets the device
1544          * wake up the upstream hub (including maybe the root hub).
1545          *
1546          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1547          * we don't explicitly enable it here.
1548          */
1549         if (udev->actconfig
1550                         // && FIXME (remote wakeup enabled on this bus)
1551                         // ... currently assuming it's always appropriate
1552                         && (udev->actconfig->desc.bmAttributes
1553                                 & USB_CONFIG_ATT_WAKEUP) != 0) {
1554                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1555                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1556                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1557                                 NULL, 0,
1558                                 USB_CTRL_SET_TIMEOUT);
1559                 if (status)
1560                         dev_dbg(&udev->dev,
1561                                 "won't remote wakeup, status %d\n",
1562                                 status);
1563         }
1564
1565         /* see 7.1.7.6 */
1566         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1567         if (status) {
1568                 dev_dbg(hub->intfdev,
1569                         "can't suspend port %d, status %d\n",
1570                         port1, status);
1571                 /* paranoia:  "should not happen" */
1572                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1573                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1574                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1575                                 NULL, 0,
1576                                 USB_CTRL_SET_TIMEOUT);
1577         } else {
1578                 /* device has up to 10 msec to fully suspend */
1579                 dev_dbg(&udev->dev, "usb suspend\n");
1580                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1581                 msleep(10);
1582         }
1583         return status;
1584 }
1585
1586 /*
1587  * Devices on USB hub ports have only one "suspend" state, corresponding
1588  * to ACPI D2, "may cause the device to lose some context".
1589  * State transitions include:
1590  *
1591  *   - suspend, resume ... when the VBUS power link stays live
1592  *   - suspend, disconnect ... VBUS lost
1593  *
1594  * Once VBUS drop breaks the circuit, the port it's using has to go through
1595  * normal re-enumeration procedures, starting with enabling VBUS power.
1596  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1597  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1598  * timer, no SRP, no requests through sysfs.
1599  */
1600 static int __usb_suspend_device (struct usb_device *udev, int port1,
1601                                  pm_message_t state)
1602 {
1603         int     status;
1604
1605         /* caller owns the udev device lock */
1606         if (port1 < 0)
1607                 return port1;
1608
1609         if (udev->state == USB_STATE_SUSPENDED
1610                         || udev->state == USB_STATE_NOTATTACHED) {
1611                 return 0;
1612         }
1613
1614         /* suspend interface drivers; if this is a hub, it
1615          * suspends the child devices
1616          */
1617         if (udev->actconfig) {
1618                 int     i;
1619
1620                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1621                         struct usb_interface    *intf;
1622                         struct usb_driver       *driver;
1623
1624                         intf = udev->actconfig->interface[i];
1625                         if (state.event <= intf->dev.power.power_state.event)
1626                                 continue;
1627                         if (!intf->dev.driver)
1628                                 continue;
1629                         driver = to_usb_driver(intf->dev.driver);
1630
1631                         if (driver->suspend) {
1632                                 status = driver->suspend(intf, state);
1633                                 if (intf->dev.power.power_state.event != state.event
1634                                                 || status)
1635                                         dev_err(&intf->dev,
1636                                                 "suspend %d fail, code %d\n",
1637                                                 state.event, status);
1638                         }
1639
1640                         /* only drivers with suspend() can ever resume();
1641                          * and after power loss, even they won't.
1642                          * bus_rescan_devices() can rebind drivers later.
1643                          *
1644                          * FIXME the PM core self-deadlocks when unbinding
1645                          * drivers during suspend/resume ... everything grabs
1646                          * dpm_sem (not a spinlock, ugh).  we want to unbind,
1647                          * since we know every driver's probe/disconnect works
1648                          * even for drivers that can't suspend.
1649                          */
1650                         if (!driver->suspend || state.event > PM_EVENT_FREEZE) {
1651 #if 1
1652                                 dev_warn(&intf->dev, "resume is unsafe!\n");
1653 #else
1654                                 down_write(&usb_bus_type.rwsem);
1655                                 device_release_driver(&intf->dev);
1656                                 up_write(&usb_bus_type.rwsem);
1657 #endif
1658                         }
1659                 }
1660         }
1661
1662         /*
1663          * FIXME this needs port power off call paths too, to help force
1664          * USB into the "generic" PM model.  At least for devices on
1665          * ports that aren't using ganged switching (usually root hubs).
1666          *
1667          * NOTE: SRP-capable links should adopt more aggressive poweroff
1668          * policies (when HNP doesn't apply) once we have mechanisms to
1669          * turn power back on!  (Likely not before 2.7...)
1670          */
1671         if (state.event > PM_EVENT_FREEZE) {
1672                 dev_warn(&udev->dev, "no poweroff yet, suspending instead\n");
1673         }
1674
1675         /* "global suspend" of the HC-to-USB interface (root hub), or
1676          * "selective suspend" of just one hub-device link.
1677          */
1678         if (!udev->parent) {
1679                 struct usb_bus  *bus = udev->bus;
1680                 if (bus && bus->op->hub_suspend) {
1681                         status = bus->op->hub_suspend (bus);
1682                         if (status == 0) {
1683                                 dev_dbg(&udev->dev, "usb suspend\n");
1684                                 usb_set_device_state(udev,
1685                                                 USB_STATE_SUSPENDED);
1686                         }
1687                 } else
1688                         status = -EOPNOTSUPP;
1689         } else
1690                 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1691                                 udev);
1692
1693         if (status == 0)
1694                 udev->dev.power.power_state = state;
1695         return status;
1696 }
1697
1698 /**
1699  * usb_suspend_device - suspend a usb device
1700  * @udev: device that's no longer in active use
1701  * @state: PMSG_SUSPEND to suspend
1702  * Context: must be able to sleep; device not locked
1703  *
1704  * Suspends a USB device that isn't in active use, conserving power.
1705  * Devices may wake out of a suspend, if anything important happens,
1706  * using the remote wakeup mechanism.  They may also be taken out of
1707  * suspend by the host, using usb_resume_device().  It's also routine
1708  * to disconnect devices while they are suspended.
1709  *
1710  * Suspending OTG devices may trigger HNP, if that's been enabled
1711  * between a pair of dual-role devices.  That will change roles, such
1712  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1713  *
1714  * Returns 0 on success, else negative errno.
1715  */
1716 int usb_suspend_device(struct usb_device *udev, pm_message_t state)
1717 {
1718         int     port1, status;
1719
1720         port1 = locktree(udev);
1721         if (port1 < 0)
1722                 return port1;
1723
1724         status = __usb_suspend_device(udev, port1, state);
1725         usb_unlock_device(udev);
1726         return status;
1727 }
1728
1729 /*
1730  * hardware resume signaling is finished, either because of selective
1731  * resume (by host) or remote wakeup (by device) ... now see what changed
1732  * in the tree that's rooted at this device.
1733  */
1734 static int finish_port_resume(struct usb_device *udev)
1735 {
1736         int     status;
1737         u16     devstatus;
1738
1739         /* caller owns the udev device lock */
1740         dev_dbg(&udev->dev, "usb resume\n");
1741
1742         /* usb ch9 identifies four variants of SUSPENDED, based on what
1743          * state the device resumes to.  Linux currently won't see the
1744          * first two on the host side; they'd be inside hub_port_init()
1745          * during many timeouts, but khubd can't suspend until later.
1746          */
1747         usb_set_device_state(udev, udev->actconfig
1748                         ? USB_STATE_CONFIGURED
1749                         : USB_STATE_ADDRESS);
1750         udev->dev.power.power_state = PMSG_ON;
1751
1752         /* 10.5.4.5 says be sure devices in the tree are still there.
1753          * For now let's assume the device didn't go crazy on resume,
1754          * and device drivers will know about any resume quirks.
1755          */
1756         status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1757         if (status < 0)
1758                 dev_dbg(&udev->dev,
1759                         "gone after usb resume? status %d\n",
1760                         status);
1761         else if (udev->actconfig) {
1762                 unsigned        i;
1763
1764                 le16_to_cpus(&devstatus);
1765                 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
1766                         status = usb_control_msg(udev,
1767                                         usb_sndctrlpipe(udev, 0),
1768                                         USB_REQ_CLEAR_FEATURE,
1769                                                 USB_RECIP_DEVICE,
1770                                         USB_DEVICE_REMOTE_WAKEUP, 0,
1771                                         NULL, 0,
1772                                         USB_CTRL_SET_TIMEOUT);
1773                         if (status) {
1774                                 dev_dbg(&udev->dev, "disable remote "
1775                                         "wakeup, status %d\n", status);
1776                                 status = 0;
1777                         }
1778                 }
1779
1780                 /* resume interface drivers; if this is a hub, it
1781                  * resumes the child devices
1782                  */
1783                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1784                         struct usb_interface    *intf;
1785                         struct usb_driver       *driver;
1786
1787                         intf = udev->actconfig->interface[i];
1788                         if (intf->dev.power.power_state.event == PM_EVENT_ON)
1789                                 continue;
1790                         if (!intf->dev.driver) {
1791                                 /* FIXME maybe force to alt 0 */
1792                                 continue;
1793                         }
1794                         driver = to_usb_driver(intf->dev.driver);
1795
1796                         /* bus_rescan_devices() may rebind drivers */
1797                         if (!driver->resume)
1798                                 continue;
1799
1800                         /* can we do better than just logging errors? */
1801                         status = driver->resume(intf);
1802                         if (intf->dev.power.power_state.event != PM_EVENT_ON
1803                                         || status)
1804                                 dev_dbg(&intf->dev,
1805                                         "resume fail, state %d code %d\n",
1806                                         intf->dev.power.power_state.event, status);
1807                 }
1808                 status = 0;
1809
1810         } else if (udev->devnum <= 0) {
1811                 dev_dbg(&udev->dev, "bogus resume!\n");
1812                 status = -EINVAL;
1813         }
1814         return status;
1815 }
1816
1817 static int
1818 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1819 {
1820         int     status;
1821
1822         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1823
1824         /* see 7.1.7.7; affects power usage, but not budgeting */
1825         status = clear_port_feature(hub->hdev,
1826                         port1, USB_PORT_FEAT_SUSPEND);
1827         if (status) {
1828                 dev_dbg(hub->intfdev,
1829                         "can't resume port %d, status %d\n",
1830                         port1, status);
1831         } else {
1832                 u16             devstatus;
1833                 u16             portchange;
1834
1835                 /* drive resume for at least 20 msec */
1836                 if (udev)
1837                         dev_dbg(&udev->dev, "RESUME\n");
1838                 msleep(25);
1839
1840 #define LIVE_FLAGS      ( USB_PORT_STAT_POWER \
1841                         | USB_PORT_STAT_ENABLE \
1842                         | USB_PORT_STAT_CONNECTION)
1843
1844                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1845                  * stop resume signaling.  Then finish the resume
1846                  * sequence.
1847                  */
1848                 devstatus = portchange = 0;
1849                 status = hub_port_status(hub, port1,
1850                                 &devstatus, &portchange);
1851                 if (status < 0
1852                                 || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
1853                                 || (devstatus & USB_PORT_STAT_SUSPEND) != 0
1854                                 ) {
1855                         dev_dbg(hub->intfdev,
1856                                 "port %d status %04x.%04x after resume, %d\n",
1857                                 port1, portchange, devstatus, status);
1858                 } else {
1859                         /* TRSMRCY = 10 msec */
1860                         msleep(10);
1861                         if (udev)
1862                                 status = finish_port_resume(udev);
1863                 }
1864         }
1865         if (status < 0)
1866                 hub_port_logical_disconnect(hub, port1);
1867
1868         return status;
1869 }
1870
1871 static int hub_resume (struct usb_interface *intf);
1872
1873 /**
1874  * usb_resume_device - re-activate a suspended usb device
1875  * @udev: device to re-activate
1876  * Context: must be able to sleep; device not locked
1877  *
1878  * This will re-activate the suspended device, increasing power usage
1879  * while letting drivers communicate again with its endpoints.
1880  * USB resume explicitly guarantees that the power session between
1881  * the host and the device is the same as it was when the device
1882  * suspended.
1883  *
1884  * Returns 0 on success, else negative errno.
1885  */
1886 int usb_resume_device(struct usb_device *udev)
1887 {
1888         int     port1, status;
1889
1890         port1 = locktree(udev);
1891         if (port1 < 0)
1892                 return port1;
1893
1894         /* "global resume" of the HC-to-USB interface (root hub), or
1895          * selective resume of one hub-to-device port
1896          */
1897         if (!udev->parent) {
1898                 struct usb_bus  *bus = udev->bus;
1899                 if (bus && bus->op->hub_resume) {
1900                         status = bus->op->hub_resume (bus);
1901                 } else
1902                         status = -EOPNOTSUPP;
1903                 if (status == 0) {
1904                         dev_dbg(&udev->dev, "usb resume\n");
1905                         /* TRSMRCY = 10 msec */
1906                         msleep(10);
1907                         usb_set_device_state (udev, USB_STATE_CONFIGURED);
1908                         udev->dev.power.power_state = PMSG_ON;
1909                         status = hub_resume (udev
1910                                         ->actconfig->interface[0]);
1911                 }
1912         } else if (udev->state == USB_STATE_SUSPENDED) {
1913                 // NOTE this fails if parent is also suspended...
1914                 status = hub_port_resume(hdev_to_hub(udev->parent),
1915                                 port1, udev);
1916         } else {
1917                 status = 0;
1918         }
1919         if (status < 0) {
1920                 dev_dbg(&udev->dev, "can't resume, status %d\n",
1921                         status);
1922         }
1923
1924         usb_unlock_device(udev);
1925
1926         /* rebind drivers that had no suspend() */
1927         if (status == 0) {
1928                 usb_lock_all_devices();
1929                 bus_rescan_devices(&usb_bus_type);
1930                 usb_unlock_all_devices();
1931         }
1932         return status;
1933 }
1934
1935 static int remote_wakeup(struct usb_device *udev)
1936 {
1937         int     status = 0;
1938
1939         /* don't repeat RESUME sequence if this device
1940          * was already woken up by some other task
1941          */
1942         down(&udev->serialize);
1943         if (udev->state == USB_STATE_SUSPENDED) {
1944                 dev_dbg(&udev->dev, "RESUME (wakeup)\n");
1945                 /* TRSMRCY = 10 msec */
1946                 msleep(10);
1947                 status = finish_port_resume(udev);
1948         }
1949         up(&udev->serialize);
1950         return status;
1951 }
1952
1953 static int hub_suspend(struct usb_interface *intf, pm_message_t state)
1954 {
1955         struct usb_hub          *hub = usb_get_intfdata (intf);
1956         struct usb_device       *hdev = hub->hdev;
1957         unsigned                port1;
1958         int                     status;
1959
1960         /* stop khubd and related activity */
1961         hub_quiesce(hub);
1962
1963         /* then suspend every port */
1964         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1965                 struct usb_device       *udev;
1966
1967                 udev = hdev->children [port1-1];
1968                 if (!udev)
1969                         continue;
1970                 down(&udev->serialize);
1971                 status = __usb_suspend_device(udev, port1, state);
1972                 up(&udev->serialize);
1973                 if (status < 0)
1974                         dev_dbg(&intf->dev, "suspend port %d --> %d\n",
1975                                 port1, status);
1976         }
1977
1978         intf->dev.power.power_state = state;
1979         return 0;
1980 }
1981
1982 static int hub_resume(struct usb_interface *intf)
1983 {
1984         struct usb_device       *hdev = interface_to_usbdev(intf);
1985         struct usb_hub          *hub = usb_get_intfdata (intf);
1986         unsigned                port1;
1987         int                     status;
1988
1989         if (intf->dev.power.power_state.event == PM_EVENT_ON)
1990                 return 0;
1991
1992         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1993                 struct usb_device       *udev;
1994                 u16                     portstat, portchange;
1995
1996                 udev = hdev->children [port1-1];
1997                 status = hub_port_status(hub, port1, &portstat, &portchange);
1998                 if (status == 0) {
1999                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2000                                 clear_port_feature(hdev, port1,
2001                                         USB_PORT_FEAT_C_SUSPEND);
2002                                 portchange &= ~USB_PORT_STAT_C_SUSPEND;
2003                         }
2004
2005                         /* let khubd handle disconnects etc */
2006                         if (portchange)
2007                                 continue;
2008                 }
2009
2010                 if (!udev || status < 0)
2011                         continue;
2012                 down (&udev->serialize);
2013                 if (portstat & USB_PORT_STAT_SUSPEND)
2014                         status = hub_port_resume(hub, port1, udev);
2015                 else {
2016                         status = finish_port_resume(udev);
2017                         if (status < 0) {
2018                                 dev_dbg(&intf->dev, "resume port %d --> %d\n",
2019                                         port1, status);
2020                                 hub_port_logical_disconnect(hub, port1);
2021                         }
2022                 }
2023                 up(&udev->serialize);
2024         }
2025         intf->dev.power.power_state = PMSG_ON;
2026
2027         hub->resume_root_hub = 0;
2028         hub_activate(hub);
2029         return 0;
2030 }
2031
2032 void usb_resume_root_hub(struct usb_device *hdev)
2033 {
2034         struct usb_hub *hub = hdev_to_hub(hdev);
2035
2036         hub->resume_root_hub = 1;
2037         kick_khubd(hub);
2038 }
2039
2040 #else   /* !CONFIG_USB_SUSPEND */
2041
2042 int usb_suspend_device(struct usb_device *udev, pm_message_t state)
2043 {
2044         return 0;
2045 }
2046
2047 int usb_resume_device(struct usb_device *udev)
2048 {
2049         return 0;
2050 }
2051
2052 #define hub_suspend             NULL
2053 #define hub_resume              NULL
2054 #define remote_wakeup(x)        0
2055
2056 #endif  /* CONFIG_USB_SUSPEND */
2057
2058 EXPORT_SYMBOL(usb_suspend_device);
2059 EXPORT_SYMBOL(usb_resume_device);
2060
2061
2062
2063 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2064  *
2065  * Between connect detection and reset signaling there must be a delay
2066  * of 100ms at least for debounce and power-settling.  The corresponding
2067  * timer shall restart whenever the downstream port detects a disconnect.
2068  *
2069  * Apparently there are some bluetooth and irda-dongles and a number of
2070  * low-speed devices for which this debounce period may last over a second.
2071  * Not covered by the spec - but easy to deal with.
2072  *
2073  * This implementation uses a 1500ms total debounce timeout; if the
2074  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
2075  * every 25ms for transient disconnects.  When the port status has been
2076  * unchanged for 100ms it returns the port status.
2077  */
2078
2079 #define HUB_DEBOUNCE_TIMEOUT    1500
2080 #define HUB_DEBOUNCE_STEP         25
2081 #define HUB_DEBOUNCE_STABLE      100
2082
2083 static int hub_port_debounce(struct usb_hub *hub, int port1)
2084 {
2085         int ret;
2086         int total_time, stable_time = 0;
2087         u16 portchange, portstatus;
2088         unsigned connection = 0xffff;
2089
2090         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2091                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2092                 if (ret < 0)
2093                         return ret;
2094
2095                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2096                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2097                         stable_time += HUB_DEBOUNCE_STEP;
2098                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2099                                 break;
2100                 } else {
2101                         stable_time = 0;
2102                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2103                 }
2104
2105                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2106                         clear_port_feature(hub->hdev, port1,
2107                                         USB_PORT_FEAT_C_CONNECTION);
2108                 }
2109
2110                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2111                         break;
2112                 msleep(HUB_DEBOUNCE_STEP);
2113         }
2114
2115         dev_dbg (hub->intfdev,
2116                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2117                 port1, total_time, stable_time, portstatus);
2118
2119         if (stable_time < HUB_DEBOUNCE_STABLE)
2120                 return -ETIMEDOUT;
2121         return portstatus;
2122 }
2123
2124 static void ep0_reinit(struct usb_device *udev)
2125 {
2126         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2127         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2128         udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2129 }
2130
2131 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2132 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2133
2134 static int hub_set_address(struct usb_device *udev)
2135 {
2136         int retval;
2137
2138         if (udev->devnum == 0)
2139                 return -EINVAL;
2140         if (udev->state == USB_STATE_ADDRESS)
2141                 return 0;
2142         if (udev->state != USB_STATE_DEFAULT)
2143                 return -EINVAL;
2144         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2145                 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2146                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2147         if (retval == 0) {
2148                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2149                 ep0_reinit(udev);
2150         }
2151         return retval;
2152 }
2153
2154 /* Reset device, (re)assign address, get device descriptor.
2155  * Device connection must be stable, no more debouncing needed.
2156  * Returns device in USB_STATE_ADDRESS, except on error.
2157  *
2158  * If this is called for an already-existing device (as part of
2159  * usb_reset_device), the caller must own the device lock.  For a
2160  * newly detected device that is not accessible through any global
2161  * pointers, it's not necessary to lock the device.
2162  */
2163 static int
2164 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2165                 int retry_counter)
2166 {
2167         static DECLARE_MUTEX(usb_address0_sem);
2168
2169         struct usb_device       *hdev = hub->hdev;
2170         int                     i, j, retval;
2171         unsigned                delay = HUB_SHORT_RESET_TIME;
2172         enum usb_device_speed   oldspeed = udev->speed;
2173
2174         /* root hub ports have a slightly longer reset period
2175          * (from USB 2.0 spec, section 7.1.7.5)
2176          */
2177         if (!hdev->parent) {
2178                 delay = HUB_ROOT_RESET_TIME;
2179                 if (port1 == hdev->bus->otg_port)
2180                         hdev->bus->b_hnp_enable = 0;
2181         }
2182
2183         /* Some low speed devices have problems with the quick delay, so */
2184         /*  be a bit pessimistic with those devices. RHbug #23670 */
2185         if (oldspeed == USB_SPEED_LOW)
2186                 delay = HUB_LONG_RESET_TIME;
2187
2188         down(&usb_address0_sem);
2189
2190         /* Reset the device; full speed may morph to high speed */
2191         retval = hub_port_reset(hub, port1, udev, delay);
2192         if (retval < 0)         /* error or disconnect */
2193                 goto fail;
2194                                 /* success, speed is known */
2195         retval = -ENODEV;
2196
2197         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2198                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2199                 goto fail;
2200         }
2201         oldspeed = udev->speed;
2202
2203         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2204          * it's fixed size except for full speed devices.
2205          */
2206         switch (udev->speed) {
2207         case USB_SPEED_HIGH:            /* fixed at 64 */
2208                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2209                 break;
2210         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2211                 /* to determine the ep0 maxpacket size, try to read
2212                  * the device descriptor to get bMaxPacketSize0 and
2213                  * then correct our initial guess.
2214                  */
2215                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2216                 break;
2217         case USB_SPEED_LOW:             /* fixed at 8 */
2218                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2219                 break;
2220         default:
2221                 goto fail;
2222         }
2223
2224         dev_info (&udev->dev,
2225                         "%s %s speed USB device using %s and address %d\n",
2226                         (udev->config) ? "reset" : "new",
2227                         ({ char *speed; switch (udev->speed) {
2228                         case USB_SPEED_LOW:     speed = "low";  break;
2229                         case USB_SPEED_FULL:    speed = "full"; break;
2230                         case USB_SPEED_HIGH:    speed = "high"; break;
2231                         default:                speed = "?";    break;
2232                         }; speed;}),
2233                         udev->bus->controller->driver->name,
2234                         udev->devnum);
2235
2236         /* Set up TT records, if needed  */
2237         if (hdev->tt) {
2238                 udev->tt = hdev->tt;
2239                 udev->ttport = hdev->ttport;
2240         } else if (udev->speed != USB_SPEED_HIGH
2241                         && hdev->speed == USB_SPEED_HIGH) {
2242                 udev->tt = &hub->tt;
2243                 udev->ttport = port1;
2244         }
2245
2246         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2247          * Because device hardware and firmware is sometimes buggy in
2248          * this area, and this is how Linux has done it for ages.
2249          * Change it cautiously.
2250          *
2251          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2252          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2253          * so it may help with some non-standards-compliant devices.
2254          * Otherwise we start with SET_ADDRESS and then try to read the
2255          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2256          * value.
2257          */
2258         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2259                 if (USE_NEW_SCHEME(retry_counter)) {
2260                         struct usb_device_descriptor *buf;
2261                         int r = 0;
2262
2263 #define GET_DESCRIPTOR_BUFSIZE  64
2264                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2265                         if (!buf) {
2266                                 retval = -ENOMEM;
2267                                 continue;
2268                         }
2269
2270                         /* Use a short timeout the first time through,
2271                          * so that recalcitrant full-speed devices with
2272                          * 8- or 16-byte ep0-maxpackets won't slow things
2273                          * down tremendously by NAKing the unexpectedly
2274                          * early status stage.  Also, retry on all errors;
2275                          * some devices are flakey.
2276                          */
2277                         for (j = 0; j < 3; ++j) {
2278                                 buf->bMaxPacketSize0 = 0;
2279                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2280                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2281                                         USB_DT_DEVICE << 8, 0,
2282                                         buf, GET_DESCRIPTOR_BUFSIZE,
2283                                         (i ? USB_CTRL_GET_TIMEOUT : 1000));
2284                                 switch (buf->bMaxPacketSize0) {
2285                                 case 8: case 16: case 32: case 64:
2286                                         if (buf->bDescriptorType ==
2287                                                         USB_DT_DEVICE) {
2288                                                 r = 0;
2289                                                 break;
2290                                         }
2291                                         /* FALL THROUGH */
2292                                 default:
2293                                         if (r == 0)
2294                                                 r = -EPROTO;
2295                                         break;
2296                                 }
2297                                 if (r == 0)
2298                                         break;
2299                         }
2300                         udev->descriptor.bMaxPacketSize0 =
2301                                         buf->bMaxPacketSize0;
2302                         kfree(buf);
2303
2304                         retval = hub_port_reset(hub, port1, udev, delay);
2305                         if (retval < 0)         /* error or disconnect */
2306                                 goto fail;
2307                         if (oldspeed != udev->speed) {
2308                                 dev_dbg(&udev->dev,
2309                                         "device reset changed speed!\n");
2310                                 retval = -ENODEV;
2311                                 goto fail;
2312                         }
2313                         if (r) {
2314                                 dev_err(&udev->dev, "device descriptor "
2315                                                 "read/%s, error %d\n",
2316                                                 "64", r);
2317                                 retval = -EMSGSIZE;
2318                                 continue;
2319                         }
2320 #undef GET_DESCRIPTOR_BUFSIZE
2321                 }
2322
2323                 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2324                         retval = hub_set_address(udev);
2325                         if (retval >= 0)
2326                                 break;
2327                         msleep(200);
2328                 }
2329                 if (retval < 0) {
2330                         dev_err(&udev->dev,
2331                                 "device not accepting address %d, error %d\n",
2332                                 udev->devnum, retval);
2333                         goto fail;
2334                 }
2335
2336                 /* cope with hardware quirkiness:
2337                  *  - let SET_ADDRESS settle, some device hardware wants it
2338                  *  - read ep0 maxpacket even for high and low speed,
2339                  */
2340                 msleep(10);
2341                 if (USE_NEW_SCHEME(retry_counter))
2342                         break;
2343
2344                 retval = usb_get_device_descriptor(udev, 8);
2345                 if (retval < 8) {
2346                         dev_err(&udev->dev, "device descriptor "
2347                                         "read/%s, error %d\n",
2348                                         "8", retval);
2349                         if (retval >= 0)
2350                                 retval = -EMSGSIZE;
2351                 } else {
2352                         retval = 0;
2353                         break;
2354                 }
2355         }
2356         if (retval)
2357                 goto fail;
2358
2359         i = udev->descriptor.bMaxPacketSize0;
2360         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2361                 if (udev->speed != USB_SPEED_FULL ||
2362                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2363                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2364                         retval = -EMSGSIZE;
2365                         goto fail;
2366                 }
2367                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2368                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2369                 ep0_reinit(udev);
2370         }
2371
2372         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2373         if (retval < (signed)sizeof(udev->descriptor)) {
2374                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2375                         "all", retval);
2376                 if (retval >= 0)
2377                         retval = -ENOMSG;
2378                 goto fail;
2379         }
2380
2381         retval = 0;
2382
2383 fail:
2384         if (retval)
2385                 hub_port_disable(hub, port1, 0);
2386         up(&usb_address0_sem);
2387         return retval;
2388 }
2389
2390 static void
2391 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2392 {
2393         struct usb_qualifier_descriptor *qual;
2394         int                             status;
2395
2396         qual = kmalloc (sizeof *qual, SLAB_KERNEL);
2397         if (qual == NULL)
2398                 return;
2399
2400         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2401                         qual, sizeof *qual);
2402         if (status == sizeof *qual) {
2403                 dev_info(&udev->dev, "not running at top speed; "
2404                         "connect to a high speed hub\n");
2405                 /* hub LEDs are probably harder to miss than syslog */
2406                 if (hub->has_indicators) {
2407                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2408                         schedule_work (&hub->leds);
2409                 }
2410         }
2411         kfree(qual);
2412 }
2413
2414 static unsigned
2415 hub_power_remaining (struct usb_hub *hub)
2416 {
2417         struct usb_device *hdev = hub->hdev;
2418         int remaining;
2419         unsigned i;
2420
2421         remaining = hub->power_budget;
2422         if (!remaining)         /* self-powered */
2423                 return 0;
2424
2425         for (i = 0; i < hdev->maxchild; i++) {
2426                 struct usb_device       *udev = hdev->children[i];
2427                 int                     delta, ceiling;
2428
2429                 if (!udev)
2430                         continue;
2431
2432                 /* 100mA per-port ceiling, or 8mA for OTG ports */
2433                 if (i != (udev->bus->otg_port - 1) || hdev->parent)
2434                         ceiling = 50;
2435                 else
2436                         ceiling = 4;
2437
2438                 if (udev->actconfig)
2439                         delta = udev->actconfig->desc.bMaxPower;
2440                 else
2441                         delta = ceiling;
2442                 // dev_dbg(&udev->dev, "budgeted %dmA\n", 2 * delta);
2443                 if (delta > ceiling)
2444                         dev_warn(&udev->dev, "%dmA over %dmA budget!\n",
2445                                 2 * (delta - ceiling), 2 * ceiling);
2446                 remaining -= delta;
2447         }
2448         if (remaining < 0) {
2449                 dev_warn(hub->intfdev,
2450                         "%dmA over power budget!\n",
2451                         -2 * remaining);
2452                 remaining = 0;
2453         }
2454         return remaining;
2455 }
2456
2457 /* Handle physical or logical connection change events.
2458  * This routine is called when:
2459  *      a port connection-change occurs;
2460  *      a port enable-change occurs (often caused by EMI);
2461  *      usb_reset_device() encounters changed descriptors (as from
2462  *              a firmware download)
2463  * caller already locked the hub
2464  */
2465 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2466                                         u16 portstatus, u16 portchange)
2467 {
2468         struct usb_device *hdev = hub->hdev;
2469         struct device *hub_dev = hub->intfdev;
2470         int status, i;
2471
2472         dev_dbg (hub_dev,
2473                 "port %d, status %04x, change %04x, %s\n",
2474                 port1, portstatus, portchange, portspeed (portstatus));
2475
2476         if (hub->has_indicators) {
2477                 set_port_led(hub, port1, HUB_LED_AUTO);
2478                 hub->indicator[port1-1] = INDICATOR_AUTO;
2479         }
2480
2481         /* Disconnect any existing devices under this port */
2482         if (hdev->children[port1-1])
2483                 usb_disconnect(&hdev->children[port1-1]);
2484         clear_bit(port1, hub->change_bits);
2485
2486 #ifdef  CONFIG_USB_OTG
2487         /* during HNP, don't repeat the debounce */
2488         if (hdev->bus->is_b_host)
2489                 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2490 #endif
2491
2492         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2493                 status = hub_port_debounce(hub, port1);
2494                 if (status < 0) {
2495                         dev_err (hub_dev,
2496                                 "connect-debounce failed, port %d disabled\n",
2497                                 port1);
2498                         goto done;
2499                 }
2500                 portstatus = status;
2501         }
2502
2503         /* Return now if nothing is connected */
2504         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2505
2506                 /* maybe switch power back on (e.g. root hub was reset) */
2507                 if ((hub->descriptor->wHubCharacteristics
2508                                         & HUB_CHAR_LPSM) < 2
2509                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2510                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2511
2512                 if (portstatus & USB_PORT_STAT_ENABLE)
2513                         goto done;
2514                 return;
2515         }
2516
2517 #ifdef  CONFIG_USB_SUSPEND
2518         /* If something is connected, but the port is suspended, wake it up. */
2519         if (portstatus & USB_PORT_STAT_SUSPEND) {
2520                 status = hub_port_resume(hub, port1, NULL);
2521                 if (status < 0) {
2522                         dev_dbg(hub_dev,
2523                                 "can't clear suspend on port %d; %d\n",
2524                                 port1, status);
2525                         goto done;
2526                 }
2527         }
2528 #endif
2529
2530         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2531                 struct usb_device *udev;
2532
2533                 /* reallocate for each attempt, since references
2534                  * to the previous one can escape in various ways
2535                  */
2536                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2537                 if (!udev) {
2538                         dev_err (hub_dev,
2539                                 "couldn't allocate port %d usb_device\n",
2540                                 port1);
2541                         goto done;
2542                 }
2543
2544                 usb_set_device_state(udev, USB_STATE_POWERED);
2545                 udev->speed = USB_SPEED_UNKNOWN;
2546
2547                 /* set the address */
2548                 choose_address(udev);
2549                 if (udev->devnum <= 0) {
2550                         status = -ENOTCONN;     /* Don't retry */
2551                         goto loop;
2552                 }
2553
2554                 /* reset and get descriptor */
2555                 status = hub_port_init(hub, udev, port1, i);
2556                 if (status < 0)
2557                         goto loop;
2558
2559                 /* consecutive bus-powered hubs aren't reliable; they can
2560                  * violate the voltage drop budget.  if the new child has
2561                  * a "powered" LED, users should notice we didn't enable it
2562                  * (without reading syslog), even without per-port LEDs
2563                  * on the parent.
2564                  */
2565                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2566                                 && hub->power_budget) {
2567                         u16     devstat;
2568
2569                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2570                                         &devstat);
2571                         if (status < 0) {
2572                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2573                                 goto loop_disable;
2574                         }
2575                         cpu_to_le16s(&devstat);
2576                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2577                                 dev_err(&udev->dev,
2578                                         "can't connect bus-powered hub "
2579                                         "to this port\n");
2580                                 if (hub->has_indicators) {
2581                                         hub->indicator[port1-1] =
2582                                                 INDICATOR_AMBER_BLINK;
2583                                         schedule_work (&hub->leds);
2584                                 }
2585                                 status = -ENOTCONN;     /* Don't retry */
2586                                 goto loop_disable;
2587                         }
2588                 }
2589
2590                 /* check for devices running slower than they could */
2591                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2592                                 && udev->speed == USB_SPEED_FULL
2593                                 && highspeed_hubs != 0)
2594                         check_highspeed (hub, udev, port1);
2595
2596                 /* Store the parent's children[] pointer.  At this point
2597                  * udev becomes globally accessible, although presumably
2598                  * no one will look at it until hdev is unlocked.
2599                  */
2600                 down (&udev->serialize);
2601                 status = 0;
2602
2603                 /* We mustn't add new devices if the parent hub has
2604                  * been disconnected; we would race with the
2605                  * recursively_mark_NOTATTACHED() routine.
2606                  */
2607                 spin_lock_irq(&device_state_lock);
2608                 if (hdev->state == USB_STATE_NOTATTACHED)
2609                         status = -ENOTCONN;
2610                 else
2611                         hdev->children[port1-1] = udev;
2612                 spin_unlock_irq(&device_state_lock);
2613
2614                 /* Run it through the hoops (find a driver, etc) */
2615                 if (!status) {
2616                         status = usb_new_device(udev);
2617                         if (status) {
2618                                 spin_lock_irq(&device_state_lock);
2619                                 hdev->children[port1-1] = NULL;
2620                                 spin_unlock_irq(&device_state_lock);
2621                         }
2622                 }
2623
2624                 up (&udev->serialize);
2625                 if (status)
2626                         goto loop_disable;
2627
2628                 status = hub_power_remaining(hub);
2629                 if (status)
2630                         dev_dbg(hub_dev,
2631                                 "%dmA power budget left\n",
2632                                 2 * status);
2633
2634                 return;
2635
2636 loop_disable:
2637                 hub_port_disable(hub, port1, 1);
2638 loop:
2639                 ep0_reinit(udev);
2640                 release_address(udev);
2641                 usb_put_dev(udev);
2642                 if (status == -ENOTCONN)
2643                         break;
2644         }
2645
2646 done:
2647         hub_port_disable(hub, port1, 1);
2648 }
2649
2650 static void hub_events(void)
2651 {
2652         struct list_head *tmp;
2653         struct usb_device *hdev;
2654         struct usb_interface *intf;
2655         struct usb_hub *hub;
2656         struct device *hub_dev;
2657         u16 hubstatus;
2658         u16 hubchange;
2659         u16 portstatus;
2660         u16 portchange;
2661         int i, ret;
2662         int connect_change;
2663
2664         /*
2665          *  We restart the list every time to avoid a deadlock with
2666          * deleting hubs downstream from this one. This should be
2667          * safe since we delete the hub from the event list.
2668          * Not the most efficient, but avoids deadlocks.
2669          */
2670         while (1) {
2671
2672                 /* Grab the first entry at the beginning of the list */
2673                 spin_lock_irq(&hub_event_lock);
2674                 if (list_empty(&hub_event_list)) {
2675                         spin_unlock_irq(&hub_event_lock);
2676                         break;
2677                 }
2678
2679                 tmp = hub_event_list.next;
2680                 list_del_init(tmp);
2681
2682                 hub = list_entry(tmp, struct usb_hub, event_list);
2683                 hdev = hub->hdev;
2684                 intf = to_usb_interface(hub->intfdev);
2685                 hub_dev = &intf->dev;
2686
2687                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
2688                                 hdev->state, hub->descriptor
2689                                         ? hub->descriptor->bNbrPorts
2690                                         : 0,
2691                                 /* NOTE: expects max 15 ports... */
2692                                 (u16) hub->change_bits[0],
2693                                 (u16) hub->event_bits[0]);
2694
2695                 usb_get_intf(intf);
2696                 i = hub->resume_root_hub;
2697                 spin_unlock_irq(&hub_event_lock);
2698
2699                 /* Is this is a root hub wanting to be resumed? */
2700                 if (i)
2701                         usb_resume_device(hdev);
2702
2703                 /* Lock the device, then check to see if we were
2704                  * disconnected while waiting for the lock to succeed. */
2705                 if (locktree(hdev) < 0) {
2706                         usb_put_intf(intf);
2707                         continue;
2708                 }
2709                 if (hub != usb_get_intfdata(intf))
2710                         goto loop;
2711
2712                 /* If the hub has died, clean up after it */
2713                 if (hdev->state == USB_STATE_NOTATTACHED) {
2714                         hub_pre_reset(hub);
2715                         goto loop;
2716                 }
2717
2718                 /* If this is an inactive or suspended hub, do nothing */
2719                 if (hub->quiescing)
2720                         goto loop;
2721
2722                 if (hub->error) {
2723                         dev_dbg (hub_dev, "resetting for error %d\n",
2724                                 hub->error);
2725
2726                         ret = usb_reset_device(hdev);
2727                         if (ret) {
2728                                 dev_dbg (hub_dev,
2729                                         "error resetting hub: %d\n", ret);
2730                                 goto loop;
2731                         }
2732
2733                         hub->nerrors = 0;
2734                         hub->error = 0;
2735                 }
2736
2737                 /* deal with port status changes */
2738                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2739                         if (test_bit(i, hub->busy_bits))
2740                                 continue;
2741                         connect_change = test_bit(i, hub->change_bits);
2742                         if (!test_and_clear_bit(i, hub->event_bits) &&
2743                                         !connect_change && !hub->activating)
2744                                 continue;
2745
2746                         ret = hub_port_status(hub, i,
2747                                         &portstatus, &portchange);
2748                         if (ret < 0)
2749                                 continue;
2750
2751                         if (hub->activating && !hdev->children[i-1] &&
2752                                         (portstatus &
2753                                                 USB_PORT_STAT_CONNECTION))
2754                                 connect_change = 1;
2755
2756                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2757                                 clear_port_feature(hdev, i,
2758                                         USB_PORT_FEAT_C_CONNECTION);
2759                                 connect_change = 1;
2760                         }
2761
2762                         if (portchange & USB_PORT_STAT_C_ENABLE) {
2763                                 if (!connect_change)
2764                                         dev_dbg (hub_dev,
2765                                                 "port %d enable change, "
2766                                                 "status %08x\n",
2767                                                 i, portstatus);
2768                                 clear_port_feature(hdev, i,
2769                                         USB_PORT_FEAT_C_ENABLE);
2770
2771                                 /*
2772                                  * EM interference sometimes causes badly
2773                                  * shielded USB devices to be shutdown by
2774                                  * the hub, this hack enables them again.
2775                                  * Works at least with mouse driver.
2776                                  */
2777                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
2778                                     && !connect_change
2779                                     && hdev->children[i-1]) {
2780                                         dev_err (hub_dev,
2781                                             "port %i "
2782                                             "disabled by hub (EMI?), "
2783                                             "re-enabling...\n",
2784                                                 i);
2785                                         connect_change = 1;
2786                                 }
2787                         }
2788
2789                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2790                                 clear_port_feature(hdev, i,
2791                                         USB_PORT_FEAT_C_SUSPEND);
2792                                 if (hdev->children[i-1]) {
2793                                         ret = remote_wakeup(hdev->
2794                                                         children[i-1]);
2795                                         if (ret < 0)
2796                                                 connect_change = 1;
2797                                 } else {
2798                                         ret = -ENODEV;
2799                                         hub_port_disable(hub, i, 1);
2800                                 }
2801                                 dev_dbg (hub_dev,
2802                                         "resume on port %d, status %d\n",
2803                                         i, ret);
2804                         }
2805
2806                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2807                                 dev_err (hub_dev,
2808                                         "over-current change on port %d\n",
2809                                         i);
2810                                 clear_port_feature(hdev, i,
2811                                         USB_PORT_FEAT_C_OVER_CURRENT);
2812                                 hub_power_on(hub);
2813                         }
2814
2815                         if (portchange & USB_PORT_STAT_C_RESET) {
2816                                 dev_dbg (hub_dev,
2817                                         "reset change on port %d\n",
2818                                         i);
2819                                 clear_port_feature(hdev, i,
2820                                         USB_PORT_FEAT_C_RESET);
2821                         }
2822
2823                         if (connect_change)
2824                                 hub_port_connect_change(hub, i,
2825                                                 portstatus, portchange);
2826                 } /* end for i */
2827
2828                 /* deal with hub status changes */
2829                 if (test_and_clear_bit(0, hub->event_bits) == 0)
2830                         ;       /* do nothing */
2831                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2832                         dev_err (hub_dev, "get_hub_status failed\n");
2833                 else {
2834                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2835                                 dev_dbg (hub_dev, "power change\n");
2836                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2837                         }
2838                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
2839                                 dev_dbg (hub_dev, "overcurrent change\n");
2840                                 msleep(500);    /* Cool down */
2841                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2842                                 hub_power_on(hub);
2843                         }
2844                 }
2845
2846                 hub->activating = 0;
2847
2848                 /* If this is a root hub, tell the HCD it's okay to
2849                  * re-enable port-change interrupts now. */
2850                 if (!hdev->parent)
2851                         usb_enable_root_hub_irq(hdev->bus);
2852
2853 loop:
2854                 usb_unlock_device(hdev);
2855                 usb_put_intf(intf);
2856
2857         } /* end while (1) */
2858 }
2859
2860 static int hub_thread(void *__unused)
2861 {
2862         do {
2863                 hub_events();
2864                 wait_event_interruptible(khubd_wait,
2865                                 !list_empty(&hub_event_list) ||
2866                                 kthread_should_stop());
2867                 try_to_freeze();
2868         } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2869
2870         pr_debug("%s: khubd exiting\n", usbcore_name);
2871         return 0;
2872 }
2873
2874 static struct usb_device_id hub_id_table [] = {
2875     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2876       .bDeviceClass = USB_CLASS_HUB},
2877     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2878       .bInterfaceClass = USB_CLASS_HUB},
2879     { }                                         /* Terminating entry */
2880 };
2881
2882 MODULE_DEVICE_TABLE (usb, hub_id_table);
2883
2884 static struct usb_driver hub_driver = {
2885         .owner =        THIS_MODULE,
2886         .name =         "hub",
2887         .probe =        hub_probe,
2888         .disconnect =   hub_disconnect,
2889         .suspend =      hub_suspend,
2890         .resume =       hub_resume,
2891         .ioctl =        hub_ioctl,
2892         .id_table =     hub_id_table,
2893 };
2894
2895 int usb_hub_init(void)
2896 {
2897         if (usb_register(&hub_driver) < 0) {
2898                 printk(KERN_ERR "%s: can't register hub driver\n",
2899                         usbcore_name);
2900                 return -1;
2901         }
2902
2903         khubd_task = kthread_run(hub_thread, NULL, "khubd");
2904         if (!IS_ERR(khubd_task))
2905                 return 0;
2906
2907         /* Fall through if kernel_thread failed */
2908         usb_deregister(&hub_driver);
2909         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2910
2911         return -1;
2912 }
2913
2914 void usb_hub_cleanup(void)
2915 {
2916         kthread_stop(khubd_task);
2917
2918         /*
2919          * Hub resources are freed for us by usb_deregister. It calls
2920          * usb_driver_purge on every device which in turn calls that
2921          * devices disconnect function if it is using this driver.
2922          * The hub_disconnect function takes care of releasing the
2923          * individual hub resources. -greg
2924          */
2925         usb_deregister(&hub_driver);
2926 } /* usb_hub_cleanup() */
2927
2928 static int config_descriptors_changed(struct usb_device *udev)
2929 {
2930         unsigned                        index;
2931         unsigned                        len = 0;
2932         struct usb_config_descriptor    *buf;
2933
2934         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2935                 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2936                         len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2937         }
2938         buf = kmalloc (len, SLAB_KERNEL);
2939         if (buf == NULL) {
2940                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2941                 /* assume the worst */
2942                 return 1;
2943         }
2944         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2945                 int length;
2946                 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2947
2948                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2949                                 old_length);
2950                 if (length < old_length) {
2951                         dev_dbg(&udev->dev, "config index %d, error %d\n",
2952                                         index, length);
2953                         break;
2954                 }
2955                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2956                                 != 0) {
2957                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2958                                 index, buf->bConfigurationValue);
2959                         break;
2960                 }
2961         }
2962         kfree(buf);
2963         return index != udev->descriptor.bNumConfigurations;
2964 }
2965
2966 /**
2967  * usb_reset_device - perform a USB port reset to reinitialize a device
2968  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2969  *
2970  * WARNING - don't reset any device unless drivers for all of its
2971  * interfaces are expecting that reset!  Maybe some driver->reset()
2972  * method should eventually help ensure sufficient cooperation.
2973  *
2974  * Do a port reset, reassign the device's address, and establish its
2975  * former operating configuration.  If the reset fails, or the device's
2976  * descriptors change from their values before the reset, or the original
2977  * configuration and altsettings cannot be restored, a flag will be set
2978  * telling khubd to pretend the device has been disconnected and then
2979  * re-connected.  All drivers will be unbound, and the device will be
2980  * re-enumerated and probed all over again.
2981  *
2982  * Returns 0 if the reset succeeded, -ENODEV if the device has been
2983  * flagged for logical disconnection, or some other negative error code
2984  * if the reset wasn't even attempted.
2985  *
2986  * The caller must own the device lock.  For example, it's safe to use
2987  * this from a driver probe() routine after downloading new firmware.
2988  * For calls that might not occur during probe(), drivers should lock
2989  * the device using usb_lock_device_for_reset().
2990  */
2991 int usb_reset_device(struct usb_device *udev)
2992 {
2993         struct usb_device               *parent_hdev = udev->parent;
2994         struct usb_hub                  *parent_hub;
2995         struct usb_device_descriptor    descriptor = udev->descriptor;
2996         struct usb_hub                  *hub = NULL;
2997         int                             i, ret = 0, port1 = -1;
2998
2999         if (udev->state == USB_STATE_NOTATTACHED ||
3000                         udev->state == USB_STATE_SUSPENDED) {
3001                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3002                                 udev->state);
3003                 return -EINVAL;
3004         }
3005
3006         if (!parent_hdev) {
3007                 /* this requires hcd-specific logic; see OHCI hc_restart() */
3008                 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
3009                 return -EISDIR;
3010         }
3011
3012         for (i = 0; i < parent_hdev->maxchild; i++)
3013                 if (parent_hdev->children[i] == udev) {
3014                         port1 = i + 1;
3015                         break;
3016                 }
3017
3018         if (port1 < 0) {
3019                 /* If this ever happens, it's very bad */
3020                 dev_err(&udev->dev, "Can't locate device's port!\n");
3021                 return -ENOENT;
3022         }
3023         parent_hub = hdev_to_hub(parent_hdev);
3024
3025         /* If we're resetting an active hub, take some special actions */
3026         if (udev->actconfig &&
3027                         udev->actconfig->interface[0]->dev.driver ==
3028                                 &hub_driver.driver &&
3029                         (hub = hdev_to_hub(udev)) != NULL) {
3030                 hub_pre_reset(hub);
3031         }
3032
3033         set_bit(port1, parent_hub->busy_bits);
3034         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
3035
3036                 /* ep0 maxpacket size may change; let the HCD know about it.
3037                  * Other endpoints will be handled by re-enumeration. */
3038                 ep0_reinit(udev);
3039                 ret = hub_port_init(parent_hub, udev, port1, i);
3040                 if (ret >= 0)
3041                         break;
3042         }
3043         clear_bit(port1, parent_hub->busy_bits);
3044         if (ret < 0)
3045                 goto re_enumerate;
3046
3047         /* Device might have changed firmware (DFU or similar) */
3048         if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
3049                         || config_descriptors_changed (udev)) {
3050                 dev_info(&udev->dev, "device firmware changed\n");
3051                 udev->descriptor = descriptor;  /* for disconnect() calls */
3052                 goto re_enumerate;
3053         }
3054
3055         if (!udev->actconfig)
3056                 goto done;
3057
3058         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3059                         USB_REQ_SET_CONFIGURATION, 0,
3060                         udev->actconfig->desc.bConfigurationValue, 0,
3061                         NULL, 0, USB_CTRL_SET_TIMEOUT);
3062         if (ret < 0) {
3063                 dev_err(&udev->dev,
3064                         "can't restore configuration #%d (error=%d)\n",
3065                         udev->actconfig->desc.bConfigurationValue, ret);
3066                 goto re_enumerate;
3067         }
3068         usb_set_device_state(udev, USB_STATE_CONFIGURED);
3069
3070         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3071                 struct usb_interface *intf = udev->actconfig->interface[i];
3072                 struct usb_interface_descriptor *desc;
3073
3074                 /* set_interface resets host side toggle even
3075                  * for altsetting zero.  the interface may have no driver.
3076                  */
3077                 desc = &intf->cur_altsetting->desc;
3078                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3079                         desc->bAlternateSetting);
3080                 if (ret < 0) {
3081                         dev_err(&udev->dev, "failed to restore interface %d "
3082                                 "altsetting %d (error=%d)\n",
3083                                 desc->bInterfaceNumber,
3084                                 desc->bAlternateSetting,
3085                                 ret);
3086                         goto re_enumerate;
3087                 }
3088         }
3089
3090 done:
3091         if (hub)
3092                 hub_post_reset(hub);
3093         return 0;
3094
3095 re_enumerate:
3096         hub_port_logical_disconnect(parent_hub, port1);
3097         return -ENODEV;
3098 }