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         hub->activating = 0;
 457         usb_kill_urb(hub->urb);
 458         if (hub->has_indicators)
 459                 cancel_delayed_work(&hub->leds);
 460         if (hub->has_indicators || hub->tt.hub)
 461                 flush_scheduled_work();
 462 }
 463
 464 static void hub_activate(struct usb_hub *hub)
 465 {
 466         int     status;
 467
 468         hub->quiescing = 0;
 469         hub->activating = 1;
 470         status = usb_submit_urb(hub->urb, GFP_NOIO);
 471         if (status < 0)
 472                 dev_err(hub->intfdev, "activate --> %d\n", status);
 473         if (hub->has_indicators && blinkenlights)
 474                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 475
 476         /* scan all ports ASAP */
 477         kick_khubd(hub);
 478 }
 479
 480 static int hub_hub_status(struct usb_hub *hub,
 481                 u16 *status, u16 *change)
 482 {
 483         int ret;
 484
 485         ret = get_hub_status(hub->hdev, &hub->status->hub);
 486         if (ret < 0)
 487                 dev_err (hub->intfdev,
 488                         "%s failed (err = %d)\n", __FUNCTION__, ret);
 489         else {
 490                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
 491                 *change = le16_to_cpu(hub->status->hub.wHubChange);
 492                 ret = 0;
 493         }
 494         return ret;
 495 }
 496
 497 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
 498 {
 499         struct usb_device *hdev = hub->hdev;
 500         int ret;
 501
 502         if (hdev->children[port1-1] && set_state) {
 503                 usb_set_device_state(hdev->children[port1-1],
 504                                 USB_STATE_NOTATTACHED);
 505         }
 506         ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
 507         if (ret)
 508                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
 509                         port1, ret);
 510
 511         return ret;
 512 }
 513
 514 static int hub_configure(struct usb_hub *hub,
 515         struct usb_endpoint_descriptor *endpoint)
 516 {
 517         struct usb_device *hdev = hub->hdev;
 518         struct device *hub_dev = hub->intfdev;
 519         u16 hubstatus, hubchange;
 520         unsigned int pipe;
 521         int maxp, ret;
 522         char *message;
 523
 524         hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
 525                         &hub->buffer_dma);
 526         if (!hub->buffer) {
 527                 message = "can't allocate hub irq buffer";
 528                 ret = -ENOMEM;
 529                 goto fail;
 530         }
 531
 532         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
 533         if (!hub->status) {
 534                 message = "can't kmalloc hub status buffer";
 535                 ret = -ENOMEM;
 536                 goto fail;
 537         }
 538
 539         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
 540         if (!hub->descriptor) {
 541                 message = "can't kmalloc hub descriptor";
 542                 ret = -ENOMEM;
 543                 goto fail;
 544         }
 545
 546         /* Request the entire hub descriptor.
 547          * hub->descriptor can handle USB_MAXCHILDREN ports,
 548          * but the hub can/will return fewer bytes here.
 549          */
 550         ret = get_hub_descriptor(hdev, hub->descriptor,
 551                         sizeof(*hub->descriptor));
 552         if (ret < 0) {
 553                 message = "can't read hub descriptor";
 554                 goto fail;
 555         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
 556                 message = "hub has too many ports!";
 557                 ret = -ENODEV;
 558                 goto fail;
 559         }
 560
 561         hdev->maxchild = hub->descriptor->bNbrPorts;
 562         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
 563                 (hdev->maxchild == 1) ? "" : "s");
 564
 565         le16_to_cpus(&hub->descriptor->wHubCharacteristics);
 566
 567         if (hub->descriptor->wHubCharacteristics & HUB_CHAR_COMPOUND) {
 568                 int     i;
 569                 char    portstr [USB_MAXCHILDREN + 1];
 570
 571                 for (i = 0; i < hdev->maxchild; i++)
 572                         portstr[i] = hub->descriptor->DeviceRemovable
 573                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
 574                                 ? 'F' : 'R';
 575                 portstr[hdev->maxchild] = 0;
 576                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
 577         } else
 578                 dev_dbg(hub_dev, "standalone hub\n");
 579
 580         switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_LPSM) {
 581                 case 0x00:
 582                         dev_dbg(hub_dev, "ganged power switching\n");
 583                         break;
 584                 case 0x01:
 585                         dev_dbg(hub_dev, "individual port power switching\n");
 586                         break;
 587                 case 0x02:
 588                 case 0x03:
 589                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
 590                         break;
 591         }
 592
 593         switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) {
 594                 case 0x00:
 595                         dev_dbg(hub_dev, "global over-current protection\n");
 596                         break;
 597                 case 0x08:
 598                         dev_dbg(hub_dev, "individual port over-current protection\n");
 599                         break;
 600                 case 0x10:
 601                 case 0x18:
 602                         dev_dbg(hub_dev, "no over-current protection\n");
 603                         break;
 604         }
 605
 606         spin_lock_init (&hub->tt.lock);
 607         INIT_LIST_HEAD (&hub->tt.clear_list);
 608         INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub);
 609         switch (hdev->descriptor.bDeviceProtocol) {
 610                 case 0:
 611                         break;
 612                 case 1:
 613                         dev_dbg(hub_dev, "Single TT\n");
 614                         hub->tt.hub = hdev;
 615                         break;
 616                 case 2:
 617                         ret = usb_set_interface(hdev, 0, 1);
 618                         if (ret == 0) {
 619                                 dev_dbg(hub_dev, "TT per port\n");
 620                                 hub->tt.multi = 1;
 621                         } else
 622                                 dev_err(hub_dev, "Using single TT (err %d)\n",
 623                                         ret);
 624                         hub->tt.hub = hdev;
 625                         break;
 626                 default:
 627                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
 628                                 hdev->descriptor.bDeviceProtocol);
 629                         break;
 630         }
 631
 632         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
 633         switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_TTTT) {
 634                 case HUB_TTTT_8_BITS:
 635                         if (hdev->descriptor.bDeviceProtocol != 0) {
 636                                 hub->tt.think_time = 666;
 637                                 dev_dbg(hub_dev, "TT requires at most %d "
 638                                                 "FS bit times (%d ns)\n",
 639                                         8, hub->tt.think_time);
 640                         }
 641                         break;
 642                 case HUB_TTTT_16_BITS:
 643                         hub->tt.think_time = 666 * 2;
 644                         dev_dbg(hub_dev, "TT requires at most %d "
 645                                         "FS bit times (%d ns)\n",
 646                                 16, hub->tt.think_time);
 647                         break;
 648                 case HUB_TTTT_24_BITS:
 649                         hub->tt.think_time = 666 * 3;
 650                         dev_dbg(hub_dev, "TT requires at most %d "
 651                                         "FS bit times (%d ns)\n",
 652                                 24, hub->tt.think_time);
 653                         break;
 654                 case HUB_TTTT_32_BITS:
 655                         hub->tt.think_time = 666 * 4;
 656                         dev_dbg(hub_dev, "TT requires at most %d "
 657                                         "FS bit times (%d ns)\n",
 658                                 32, hub->tt.think_time);
 659                         break;
 660         }
 661
 662         /* probe() zeroes hub->indicator[] */
 663         if (hub->descriptor->wHubCharacteristics & HUB_CHAR_PORTIND) {
 664                 hub->has_indicators = 1;
 665                 dev_dbg(hub_dev, "Port indicators are supported\n");
 666         }
 667
 668         dev_dbg(hub_dev, "power on to power good time: %dms\n",
 669                 hub->descriptor->bPwrOn2PwrGood * 2);
 670
 671         /* power budgeting mostly matters with bus-powered hubs,
 672          * and battery-powered root hubs (may provide just 8 mA).
 673          */
 674         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
 675         if (ret < 0) {
 676                 message = "can't get hub status";
 677                 goto fail;
 678         }
 679         le16_to_cpus(&hubstatus);
 680         if (hdev == hdev->bus->root_hub) {
 681                 struct usb_hcd *hcd =
 682                                 container_of(hdev->bus, struct usb_hcd, self);
 683
 684                 hub->power_budget = min(500u, hcd->power_budget) / 2;
 685         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
 686                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
 687                         hub->descriptor->bHubContrCurrent);
 688                 hub->power_budget = (501 - hub->descriptor->bHubContrCurrent)
 689                                         / 2;
 690         }
 691         if (hub->power_budget)
 692                 dev_dbg(hub_dev, "%dmA bus power budget for children\n",
 693                         hub->power_budget * 2);
 694
 695
 696         ret = hub_hub_status(hub, &hubstatus, &hubchange);
 697         if (ret < 0) {
 698                 message = "can't get hub status";
 699                 goto fail;
 700         }
 701
 702         /* local power status reports aren't always correct */
 703         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
 704                 dev_dbg(hub_dev, "local power source is %s\n",
 705                         (hubstatus & HUB_STATUS_LOCAL_POWER)
 706                         ? "lost (inactive)" : "good");
 707
 708         if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) == 0)
 709                 dev_dbg(hub_dev, "%sover-current condition exists\n",
 710                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
 711
 712         /* set up the interrupt endpoint */
 713         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
 714         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
 715
 716         if (maxp > sizeof(*hub->buffer))
 717                 maxp = sizeof(*hub->buffer);
 718
 719         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
 720         if (!hub->urb) {
 721                 message = "couldn't allocate interrupt urb";
 722                 ret = -ENOMEM;
 723                 goto fail;
 724         }
 725
 726         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
 727                 hub, endpoint->bInterval);
 728         hub->urb->transfer_dma = hub->buffer_dma;
 729         hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 730
 731         /* maybe cycle the hub leds */
 732         if (hub->has_indicators && blinkenlights)
 733                 hub->indicator [0] = INDICATOR_CYCLE;
 734
 735         hub_power_on(hub);
 736         hub_activate(hub);
 737         return 0;
 738
 739 fail:
 740         dev_err (hub_dev, "config failed, %s (err %d)\n",
 741                         message, ret);
 742         /* hub_disconnect() frees urb and descriptor */
 743         return ret;
 744 }
 745
 746 static unsigned highspeed_hubs;
 747
 748 /* Called after the hub driver is unbound from a hub with children */
 749 static void hub_remove_children_work(void *__hub)
 750 {
 751         struct usb_hub          *hub = __hub;
 752         struct usb_device       *hdev = hub->hdev;
 753         int                     i;
 754
 755         kfree(hub);
 756
 757         usb_lock_device(hdev);
 758         for (i = 0; i < hdev->maxchild; ++i) {
 759                 if (hdev->children[i])
 760                         usb_disconnect(&hdev->children[i]);
 761         }
 762         usb_unlock_device(hdev);
 763         usb_put_dev(hdev);
 764 }
 765
 766 static void hub_disconnect(struct usb_interface *intf)
 767 {
 768         struct usb_hub *hub = usb_get_intfdata (intf);
 769         struct usb_device *hdev;
 770         int n, port1;
 771
 772         usb_set_intfdata (intf, NULL);
 773         hdev = hub->hdev;
 774
 775         if (hdev->speed == USB_SPEED_HIGH)
 776                 highspeed_hubs--;
 777
 778         hub_quiesce(hub);
 779         usb_free_urb(hub->urb);
 780         hub->urb = NULL;
 781
 782         spin_lock_irq(&hub_event_lock);
 783         list_del_init(&hub->event_list);
 784         spin_unlock_irq(&hub_event_lock);
 785
 786         kfree(hub->descriptor);
 787         hub->descriptor = NULL;
 788
 789         kfree(hub->status);
 790         hub->status = NULL;
 791
 792         if (hub->buffer) {
 793                 usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
 794                                 hub->buffer_dma);
 795                 hub->buffer = NULL;
 796         }
 797
 798         /* If there are any children then this is an unbind only, not a
 799          * physical disconnection.  The active ports must be disabled
 800          * and later on we must call usb_disconnect().  We can't call
 801          * it now because we may not hold the hub's device lock.
 802          */
 803         n = 0;
 804         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
 805                 if (hdev->children[port1 - 1]) {
 806                         ++n;
 807                         hub_port_disable(hub, port1, 1);
 808                 }
 809         }
 810
 811         if (n == 0)
 812                 kfree(hub);
 813         else {
 814                 /* Reuse the hub->leds work_struct for our own purposes */
 815                 INIT_WORK(&hub->leds, hub_remove_children_work, hub);
 816                 schedule_work(&hub->leds);
 817                 usb_get_dev(hdev);
 818         }
 819 }
 820
 821 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
 822 {
 823         struct usb_host_interface *desc;
 824         struct usb_endpoint_descriptor *endpoint;
 825         struct usb_device *hdev;
 826         struct usb_hub *hub;
 827
 828         desc = intf->cur_altsetting;
 829         hdev = interface_to_usbdev(intf);
 830
 831         /* Some hubs have a subclass of 1, which AFAICT according to the */
 832         /*  specs is not defined, but it works */
 833         if ((desc->desc.bInterfaceSubClass != 0) &&
 834             (desc->desc.bInterfaceSubClass != 1)) {
 835 descriptor_error:
 836                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
 837                 return -EIO;
 838         }
 839
 840         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
 841         if (desc->desc.bNumEndpoints != 1)
 842                 goto descriptor_error;
 843
 844         endpoint = &desc->endpoint[0].desc;
 845
 846         /* Output endpoint? Curiouser and curiouser.. */
 847         if (!(endpoint->bEndpointAddress & USB_DIR_IN))
 848                 goto descriptor_error;
 849
 850         /* If it's not an interrupt endpoint, we'd better punt! */
 851         if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
 852                         != USB_ENDPOINT_XFER_INT)
 853                 goto descriptor_error;
 854
 855         /* We found a hub */
 856         dev_info (&intf->dev, "USB hub found\n");
 857
 858         hub = kmalloc(sizeof(*hub), GFP_KERNEL);
 859         if (!hub) {
 860                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
 861                 return -ENOMEM;
 862         }
 863
 864         memset(hub, 0, sizeof(*hub));
 865
 866         INIT_LIST_HEAD(&hub->event_list);
 867         hub->intfdev = &intf->dev;
 868         hub->hdev = hdev;
 869         INIT_WORK(&hub->leds, led_work, hub);
 870
 871         usb_set_intfdata (intf, hub);
 872
 873         if (hdev->speed == USB_SPEED_HIGH)
 874                 highspeed_hubs++;
 875
 876         if (hub_configure(hub, endpoint) >= 0)
 877                 return 0;
 878
 879         hub_disconnect (intf);
 880         return -ENODEV;
 881 }
 882
 883 static int
 884 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
 885 {
 886         struct usb_device *hdev = interface_to_usbdev (intf);
 887
 888         /* assert ifno == 0 (part of hub spec) */
 889         switch (code) {
 890         case USBDEVFS_HUB_PORTINFO: {
 891                 struct usbdevfs_hub_portinfo *info = user_data;
 892                 int i;
 893
 894                 spin_lock_irq(&device_state_lock);
 895                 if (hdev->devnum <= 0)
 896                         info->nports = 0;
 897                 else {
 898                         info->nports = hdev->maxchild;
 899                         for (i = 0; i < info->nports; i++) {
 900                                 if (hdev->children[i] == NULL)
 901                                         info->port[i] = 0;
 902                                 else
 903                                         info->port[i] =
 904                                                 hdev->children[i]->devnum;
 905                         }
 906                 }
 907                 spin_unlock_irq(&device_state_lock);
 908
 909                 return info->nports + 1;
 910                 }
 911
 912         default:
 913                 return -ENOSYS;
 914         }
 915 }
 916
 917 /* caller has locked the hub device */
 918 static void hub_pre_reset(struct usb_hub *hub)
 919 {
 920         struct usb_device *hdev = hub->hdev;
 921         int i;
 922
 923         for (i = 0; i < hdev->maxchild; ++i) {
 924                 if (hdev->children[i])
 925                         usb_disconnect(&hdev->children[i]);
 926         }
 927         hub_quiesce(hub);
 928 }
 929
 930 /* caller has locked the hub device */
 931 static void hub_post_reset(struct usb_hub *hub)
 932 {
 933         hub_activate(hub);
 934         hub_power_on(hub);
 935 }
 936
 937
 938 /* grab device/port lock, returning index of that port (zero based).
 939  * protects the upstream link used by this device from concurrent
 940  * tree operations like suspend, resume, reset, and disconnect, which
 941  * apply to everything downstream of a given port.
 942  */
 943 static int locktree(struct usb_device *udev)
 944 {
 945         int                     t;
 946         struct usb_device       *hdev;
 947
 948         if (!udev)
 949                 return -ENODEV;
 950
 951         /* root hub is always the first lock in the series */
 952         hdev = udev->parent;
 953         if (!hdev) {
 954                 usb_lock_device(udev);
 955                 return 0;
 956         }
 957
 958         /* on the path from root to us, lock everything from
 959          * top down, dropping parent locks when not needed
 960          */
 961         t = locktree(hdev);
 962         if (t < 0)
 963                 return t;
 964         for (t = 0; t < hdev->maxchild; t++) {
 965                 if (hdev->children[t] == udev) {
 966                         /* everything is fail-fast once disconnect
 967                          * processing starts
 968                          */
 969                         if (udev->state == USB_STATE_NOTATTACHED)
 970                                 break;
 971
 972                         /* when everyone grabs locks top->bottom,
 973                          * non-overlapping work may be concurrent
 974                          */
 975                         down(&udev->serialize);
 976                         up(&hdev->serialize);
 977                         return t + 1;
 978                 }
 979         }
 980         usb_unlock_device(hdev);
 981         return -ENODEV;
 982 }
 983
 984 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
 985 {
 986         int i;
 987
 988         for (i = 0; i < udev->maxchild; ++i) {
 989                 if (udev->children[i])
 990                         recursively_mark_NOTATTACHED(udev->children[i]);
 991         }
 992         udev->state = USB_STATE_NOTATTACHED;
 993 }
 994
 995 /**
 996  * usb_set_device_state - change a device's current state (usbcore, hcds)
 997  * @udev: pointer to device whose state should be changed
 998  * @new_state: new state value to be stored
 999  *
1000  * udev->state is _not_ fully protected by the device lock.  Although
1001  * most transitions are made only while holding the lock, the state can
1002  * can change to USB_STATE_NOTATTACHED at almost any time.  This
1003  * is so that devices can be marked as disconnected as soon as possible,
1004  * without having to wait for any semaphores to be released.  As a result,
1005  * all changes to any device's state must be protected by the
1006  * device_state_lock spinlock.
1007  *
1008  * Once a device has been added to the device tree, all changes to its state
1009  * should be made using this routine.  The state should _not_ be set directly.
1010  *
1011  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1012  * Otherwise udev->state is set to new_state, and if new_state is
1013  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1014  * to USB_STATE_NOTATTACHED.
1015  */
1016 void usb_set_device_state(struct usb_device *udev,
1017                 enum usb_device_state new_state)
1018 {
1019         unsigned long flags;
1020
1021         spin_lock_irqsave(&device_state_lock, flags);
1022         if (udev->state == USB_STATE_NOTATTACHED)
1023                 ;       /* do nothing */
1024         else if (new_state != USB_STATE_NOTATTACHED) {
1025                 udev->state = new_state;
1026                 if (new_state == USB_STATE_CONFIGURED)
1027                         device_init_wakeup(&udev->dev,
1028                                 (udev->actconfig->desc.bmAttributes
1029                                  & USB_CONFIG_ATT_WAKEUP));
1030                 else if (new_state != USB_STATE_SUSPENDED)
1031                         device_init_wakeup(&udev->dev, 0);
1032         } else
1033                 recursively_mark_NOTATTACHED(udev);
1034         spin_unlock_irqrestore(&device_state_lock, flags);
1035 }
1036 EXPORT_SYMBOL(usb_set_device_state);
1037
1038
1039 static void choose_address(struct usb_device *udev)
1040 {
1041         int             devnum;
1042         struct usb_bus  *bus = udev->bus;
1043
1044         /* If khubd ever becomes multithreaded, this will need a lock */
1045
1046         /* Try to allocate the next devnum beginning at bus->devnum_next. */
1047         devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1048                         bus->devnum_next);
1049         if (devnum >= 128)
1050                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1051
1052         bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1053
1054         if (devnum < 128) {
1055                 set_bit(devnum, bus->devmap.devicemap);
1056                 udev->devnum = devnum;
1057         }
1058 }
1059
1060 static void release_address(struct usb_device *udev)
1061 {
1062         if (udev->devnum > 0) {
1063                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1064                 udev->devnum = -1;
1065         }
1066 }
1067
1068 /**
1069  * usb_disconnect - disconnect a device (usbcore-internal)
1070  * @pdev: pointer to device being disconnected
1071  * Context: !in_interrupt ()
1072  *
1073  * Something got disconnected. Get rid of it and all of its children.
1074  *
1075  * If *pdev is a normal device then the parent hub must already be locked.
1076  * If *pdev is a root hub then this routine will acquire the
1077  * usb_bus_list_lock on behalf of the caller.
1078  *
1079  * Only hub drivers (including virtual root hub drivers for host
1080  * controllers) should ever call this.
1081  *
1082  * This call is synchronous, and may not be used in an interrupt context.
1083  */
1084 void usb_disconnect(struct usb_device **pdev)
1085 {
1086         struct usb_device       *udev = *pdev;
1087         int                     i;
1088
1089         if (!udev) {
1090                 pr_debug ("%s nodev\n", __FUNCTION__);
1091                 return;
1092         }
1093
1094         /* mark the device as inactive, so any further urb submissions for
1095          * this device (and any of its children) will fail immediately.
1096          * this quiesces everyting except pending urbs.
1097          */
1098         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1099
1100         /* lock the bus list on behalf of HCDs unregistering their root hubs */
1101         if (!udev->parent) {
1102                 down(&usb_bus_list_lock);
1103                 usb_lock_device(udev);
1104         } else
1105                 down(&udev->serialize);
1106
1107         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1108
1109         /* Free up all the children before we remove this device */
1110         for (i = 0; i < USB_MAXCHILDREN; i++) {
1111                 if (udev->children[i])
1112                         usb_disconnect(&udev->children[i]);
1113         }
1114
1115         /* deallocate hcd/hardware state ... nuking all pending urbs and
1116          * cleaning up all state associated with the current configuration
1117          * so that the hardware is now fully quiesced.
1118          */
1119         usb_disable_device(udev, 0);
1120
1121         /* Free the device number, remove the /proc/bus/usb entry and
1122          * the sysfs attributes, and delete the parent's children[]
1123          * (or root_hub) pointer.
1124          */
1125         dev_dbg (&udev->dev, "unregistering device\n");
1126         release_address(udev);
1127         usbfs_remove_device(udev);
1128         usbdev_remove(udev);
1129         usb_remove_sysfs_dev_files(udev);
1130
1131         /* Avoid races with recursively_mark_NOTATTACHED() */
1132         spin_lock_irq(&device_state_lock);
1133         *pdev = NULL;
1134         spin_unlock_irq(&device_state_lock);
1135
1136         if (!udev->parent) {
1137                 usb_unlock_device(udev);
1138                 up(&usb_bus_list_lock);
1139         } else
1140                 up(&udev->serialize);
1141
1142         device_unregister(&udev->dev);
1143 }
1144
1145 static int choose_configuration(struct usb_device *udev)
1146 {
1147         int c, i;
1148
1149         /* NOTE: this should interact with hub power budgeting */
1150
1151         c = udev->config[0].desc.bConfigurationValue;
1152         if (udev->descriptor.bNumConfigurations != 1) {
1153                 for (i = 0; i < udev->descriptor.bNumConfigurations; i++) {
1154                         struct usb_interface_descriptor *desc;
1155
1156                         /* heuristic:  Linux is more likely to have class
1157                          * drivers, so avoid vendor-specific interfaces.
1158                          */
1159                         desc = &udev->config[i].intf_cache[0]
1160                                         ->altsetting->desc;
1161                         if (desc->bInterfaceClass == USB_CLASS_VENDOR_SPEC)
1162                                 continue;
1163                         /* COMM/2/all is CDC ACM, except 0xff is MSFT RNDIS.
1164                          * MSFT needs this to be the first config; never use
1165                          * it as the default unless Linux has host-side RNDIS.
1166                          * A second config would ideally be CDC-Ethernet, but
1167                          * may instead be the "vendor specific" CDC subset
1168                          * long used by ARM Linux for sa1100 or pxa255.
1169                          */
1170                         if (desc->bInterfaceClass == USB_CLASS_COMM
1171                                         && desc->bInterfaceSubClass == 2
1172                                         && desc->bInterfaceProtocol == 0xff) {
1173                                 c = udev->config[1].desc.bConfigurationValue;
1174                                 continue;
1175                         }
1176                         c = udev->config[i].desc.bConfigurationValue;
1177                         break;
1178                 }
1179                 dev_info(&udev->dev,
1180                         "configuration #%d chosen from %d choices\n",
1181                         c, udev->descriptor.bNumConfigurations);
1182         }
1183         return c;
1184 }
1185
1186 #ifdef DEBUG
1187 static void show_string(struct usb_device *udev, char *id, char *string)
1188 {
1189         if (!string)
1190                 return;
1191         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1192 }
1193
1194 #else
1195 static inline void show_string(struct usb_device *udev, char *id, char *string)
1196 {}
1197 #endif
1198
1199 static void get_string(struct usb_device *udev, char **string, int index)
1200 {
1201         char *buf;
1202
1203         if (!index)
1204                 return;
1205         buf = kmalloc(256, GFP_KERNEL);
1206         if (!buf)
1207                 return;
1208         if (usb_string(udev, index, buf, 256) > 0)
1209                 *string = buf;
1210         else
1211                 kfree(buf);
1212 }
1213
1214
1215 #ifdef  CONFIG_USB_OTG
1216 #include "otg_whitelist.h"
1217 #endif
1218
1219 /**
1220  * usb_new_device - perform initial device setup (usbcore-internal)
1221  * @udev: newly addressed device (in ADDRESS state)
1222  *
1223  * This is called with devices which have been enumerated, but not yet
1224  * configured.  The device descriptor is available, but not descriptors
1225  * for any device configuration.  The caller must have locked udev and
1226  * either the parent hub (if udev is a normal device) or else the
1227  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1228  * udev has already been installed, but udev is not yet visible through
1229  * sysfs or other filesystem code.
1230  *
1231  * Returns 0 for success (device is configured and listed, with its
1232  * interfaces, in sysfs); else a negative errno value.
1233  *
1234  * This call is synchronous, and may not be used in an interrupt context.
1235  *
1236  * Only the hub driver should ever call this; root hub registration
1237  * uses it indirectly.
1238  */
1239 int usb_new_device(struct usb_device *udev)
1240 {
1241         int err;
1242         int c;
1243
1244         err = usb_get_configuration(udev);
1245         if (err < 0) {
1246                 dev_err(&udev->dev, "can't read configurations, error %d\n",
1247                         err);
1248                 goto fail;
1249         }
1250
1251         /* read the standard strings and cache them if present */
1252         get_string(udev, &udev->product, udev->descriptor.iProduct);
1253         get_string(udev, &udev->manufacturer, udev->descriptor.iManufacturer);
1254         get_string(udev, &udev->serial, udev->descriptor.iSerialNumber);
1255
1256         /* Tell the world! */
1257         dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1258                         "SerialNumber=%d\n",
1259                         udev->descriptor.iManufacturer,
1260                         udev->descriptor.iProduct,
1261                         udev->descriptor.iSerialNumber);
1262         show_string(udev, "Product", udev->product);
1263         show_string(udev, "Manufacturer", udev->manufacturer);
1264         show_string(udev, "SerialNumber", udev->serial);
1265
1266 #ifdef  CONFIG_USB_OTG
1267         /*
1268          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1269          * to wake us after we've powered off VBUS; and HNP, switching roles
1270          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1271          */
1272         if (!udev->bus->is_b_host
1273                         && udev->config
1274                         && udev->parent == udev->bus->root_hub) {
1275                 struct usb_otg_descriptor       *desc = 0;
1276                 struct usb_bus                  *bus = udev->bus;
1277
1278                 /* descriptor may appear anywhere in config */
1279                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1280                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1281                                         USB_DT_OTG, (void **) &desc) == 0) {
1282                         if (desc->bmAttributes & USB_OTG_HNP) {
1283                                 unsigned                port1;
1284                                 struct usb_device       *root = udev->parent;
1285
1286                                 for (port1 = 1; port1 <= root->maxchild;
1287                                                 port1++) {
1288                                         if (root->children[port1-1] == udev)
1289                                                 break;
1290                                 }
1291
1292                                 dev_info(&udev->dev,
1293                                         "Dual-Role OTG device on %sHNP port\n",
1294                                         (port1 == bus->otg_port)
1295                                                 ? "" : "non-");
1296
1297                                 /* enable HNP before suspend, it's simpler */
1298                                 if (port1 == bus->otg_port)
1299                                         bus->b_hnp_enable = 1;
1300                                 err = usb_control_msg(udev,
1301                                         usb_sndctrlpipe(udev, 0),
1302                                         USB_REQ_SET_FEATURE, 0,
1303                                         bus->b_hnp_enable
1304                                                 ? USB_DEVICE_B_HNP_ENABLE
1305                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1306                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1307                                 if (err < 0) {
1308                                         /* OTG MESSAGE: report errors here,
1309                                          * customize to match your product.
1310                                          */
1311                                         dev_info(&udev->dev,
1312                                                 "can't set HNP mode; %d\n",
1313                                                 err);
1314                                         bus->b_hnp_enable = 0;
1315                                 }
1316                         }
1317                 }
1318         }
1319
1320         if (!is_targeted(udev)) {
1321
1322                 /* Maybe it can talk to us, though we can't talk to it.
1323                  * (Includes HNP test device.)
1324                  */
1325                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1326                         static int __usb_suspend_device (struct usb_device *,
1327                                                 int port1, pm_message_t state);
1328                         err = __usb_suspend_device(udev,
1329                                         udev->bus->otg_port,
1330                                         PMSG_SUSPEND);
1331                         if (err < 0)
1332                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1333                 }
1334                 err = -ENODEV;
1335                 goto fail;
1336         }
1337 #endif
1338
1339         /* put device-specific files into sysfs */
1340         err = device_add (&udev->dev);
1341         if (err) {
1342                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1343                 goto fail;
1344         }
1345         usb_create_sysfs_dev_files (udev);
1346
1347         /* choose and set the configuration. that registers the interfaces
1348          * with the driver core, and lets usb device drivers bind to them.
1349          */
1350         c = choose_configuration(udev);
1351         if (c < 0)
1352                 dev_warn(&udev->dev,
1353                                 "can't choose an initial configuration\n");
1354         else {
1355                 err = usb_set_configuration(udev, c);
1356                 if (err) {
1357                         dev_err(&udev->dev, "can't set config #%d, error %d\n",
1358                                         c, err);
1359                         usb_remove_sysfs_dev_files(udev);
1360                         device_del(&udev->dev);
1361                         goto fail;
1362                 }
1363         }
1364
1365         /* USB device state == configured ... usable */
1366
1367         /* add a /proc/bus/usb entry */
1368         usbdev_add(udev);
1369         usbfs_add_device(udev);
1370         return 0;
1371
1372 fail:
1373         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1374         return err;
1375 }
1376
1377
1378 static int hub_port_status(struct usb_hub *hub, int port1,
1379                                u16 *status, u16 *change)
1380 {
1381         int ret;
1382
1383         ret = get_port_status(hub->hdev, port1, &hub->status->port);
1384         if (ret < 0)
1385                 dev_err (hub->intfdev,
1386                         "%s failed (err = %d)\n", __FUNCTION__, ret);
1387         else {
1388                 *status = le16_to_cpu(hub->status->port.wPortStatus);
1389                 *change = le16_to_cpu(hub->status->port.wPortChange);
1390                 ret = 0;
1391         }
1392         return ret;
1393 }
1394
1395 #define PORT_RESET_TRIES        5
1396 #define SET_ADDRESS_TRIES       2
1397 #define GET_DESCRIPTOR_TRIES    2
1398 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1399 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1400
1401 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1402 #define HUB_SHORT_RESET_TIME    10
1403 #define HUB_LONG_RESET_TIME     200
1404 #define HUB_RESET_TIMEOUT       500
1405
1406 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1407                                 struct usb_device *udev, unsigned int delay)
1408 {
1409         int delay_time, ret;
1410         u16 portstatus;
1411         u16 portchange;
1412
1413         for (delay_time = 0;
1414                         delay_time < HUB_RESET_TIMEOUT;
1415                         delay_time += delay) {
1416                 /* wait to give the device a chance to reset */
1417                 msleep(delay);
1418
1419                 /* read and decode port status */
1420                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1421                 if (ret < 0)
1422                         return ret;
1423
1424                 /* Device went away? */
1425                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1426                         return -ENOTCONN;
1427
1428                 /* bomb out completely if something weird happened */
1429                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1430                         return -EINVAL;
1431
1432                 /* if we`ve finished resetting, then break out of the loop */
1433                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1434                     (portstatus & USB_PORT_STAT_ENABLE)) {
1435                         if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1436                                 udev->speed = USB_SPEED_HIGH;
1437                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1438                                 udev->speed = USB_SPEED_LOW;
1439                         else
1440                                 udev->speed = USB_SPEED_FULL;
1441                         return 0;
1442                 }
1443
1444                 /* switch to the long delay after two short delay failures */
1445                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1446                         delay = HUB_LONG_RESET_TIME;
1447
1448                 dev_dbg (hub->intfdev,
1449                         "port %d not reset yet, waiting %dms\n",
1450                         port1, delay);
1451         }
1452
1453         return -EBUSY;
1454 }
1455
1456 static int hub_port_reset(struct usb_hub *hub, int port1,
1457                                 struct usb_device *udev, unsigned int delay)
1458 {
1459         int i, status;
1460
1461         /* Reset the port */
1462         for (i = 0; i < PORT_RESET_TRIES; i++) {
1463                 status = set_port_feature(hub->hdev,
1464                                 port1, USB_PORT_FEAT_RESET);
1465                 if (status)
1466                         dev_err(hub->intfdev,
1467                                         "cannot reset port %d (err = %d)\n",
1468                                         port1, status);
1469                 else {
1470                         status = hub_port_wait_reset(hub, port1, udev, delay);
1471                         if (status && status != -ENOTCONN)
1472                                 dev_dbg(hub->intfdev,
1473                                                 "port_wait_reset: err = %d\n",
1474                                                 status);
1475                 }
1476
1477                 /* return on disconnect or reset */
1478                 switch (status) {
1479                 case 0:
1480                         /* TRSTRCY = 10 ms; plus some extra */
1481                         msleep(10 + 40);
1482                         /* FALL THROUGH */
1483                 case -ENOTCONN:
1484                 case -ENODEV:
1485                         clear_port_feature(hub->hdev,
1486                                 port1, USB_PORT_FEAT_C_RESET);
1487                         /* FIXME need disconnect() for NOTATTACHED device */
1488                         usb_set_device_state(udev, status
1489                                         ? USB_STATE_NOTATTACHED
1490                                         : USB_STATE_DEFAULT);
1491                         return status;
1492                 }
1493
1494                 dev_dbg (hub->intfdev,
1495                         "port %d not enabled, trying reset again...\n",
1496                         port1);
1497                 delay = HUB_LONG_RESET_TIME;
1498         }
1499
1500         dev_err (hub->intfdev,
1501                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1502                 port1);
1503
1504         return status;
1505 }
1506
1507 /*
1508  * Disable a port and mark a logical connnect-change event, so that some
1509  * time later khubd will disconnect() any existing usb_device on the port
1510  * and will re-enumerate if there actually is a device attached.
1511  */
1512 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1513 {
1514         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1515         hub_port_disable(hub, port1, 1);
1516
1517         /* FIXME let caller ask to power down the port:
1518          *  - some devices won't enumerate without a VBUS power cycle
1519          *  - SRP saves power that way
1520          *  - usb_suspend_device(dev, PMSG_SUSPEND)
1521          * That's easy if this hub can switch power per-port, and
1522          * khubd reactivates the port later (timer, SRP, etc).
1523          * Powerdown must be optional, because of reset/DFU.
1524          */
1525
1526         set_bit(port1, hub->change_bits);
1527         kick_khubd(hub);
1528 }
1529
1530
1531 #ifdef  CONFIG_USB_SUSPEND
1532
1533 /*
1534  * Selective port suspend reduces power; most suspended devices draw
1535  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1536  * All devices below the suspended port are also suspended.
1537  *
1538  * Devices leave suspend state when the host wakes them up.  Some devices
1539  * also support "remote wakeup", where the device can activate the USB
1540  * tree above them to deliver data, such as a keypress or packet.  In
1541  * some cases, this wakes the USB host.
1542  */
1543 static int hub_port_suspend(struct usb_hub *hub, int port1,
1544                 struct usb_device *udev)
1545 {
1546         int     status;
1547
1548         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1549
1550         /* enable remote wakeup when appropriate; this lets the device
1551          * wake up the upstream hub (including maybe the root hub).
1552          *
1553          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1554          * we don't explicitly enable it here.
1555          */
1556         if (device_may_wakeup(&udev->dev)) {
1557                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1558                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1559                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1560                                 NULL, 0,
1561                                 USB_CTRL_SET_TIMEOUT);
1562                 if (status)
1563                         dev_dbg(&udev->dev,
1564                                 "won't remote wakeup, status %d\n",
1565                                 status);
1566         }
1567
1568         /* see 7.1.7.6 */
1569         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1570         if (status) {
1571                 dev_dbg(hub->intfdev,
1572                         "can't suspend port %d, status %d\n",
1573                         port1, status);
1574                 /* paranoia:  "should not happen" */
1575                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1576                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1577                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1578                                 NULL, 0,
1579                                 USB_CTRL_SET_TIMEOUT);
1580         } else {
1581                 /* device has up to 10 msec to fully suspend */
1582                 dev_dbg(&udev->dev, "usb suspend\n");
1583                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1584                 msleep(10);
1585         }
1586         return status;
1587 }
1588
1589 /*
1590  * Devices on USB hub ports have only one "suspend" state, corresponding
1591  * to ACPI D2, "may cause the device to lose some context".
1592  * State transitions include:
1593  *
1594  *   - suspend, resume ... when the VBUS power link stays live
1595  *   - suspend, disconnect ... VBUS lost
1596  *
1597  * Once VBUS drop breaks the circuit, the port it's using has to go through
1598  * normal re-enumeration procedures, starting with enabling VBUS power.
1599  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1600  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1601  * timer, no SRP, no requests through sysfs.
1602  */
1603 static int __usb_suspend_device (struct usb_device *udev, int port1,
1604                                  pm_message_t state)
1605 {
1606         int     status;
1607
1608         /* caller owns the udev device lock */
1609         if (port1 < 0)
1610                 return port1;
1611
1612         if (udev->state == USB_STATE_SUSPENDED
1613                         || udev->state == USB_STATE_NOTATTACHED) {
1614                 return 0;
1615         }
1616
1617         /* all interfaces must already be suspended */
1618         if (udev->actconfig) {
1619                 int     i;
1620
1621                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1622                         struct usb_interface    *intf;
1623
1624                         intf = udev->actconfig->interface[i];
1625                         if (is_active(intf)) {
1626                                 dev_dbg(&intf->dev, "nyet suspended\n");
1627                                 return -EBUSY;
1628                         }
1629                 }
1630         }
1631
1632         /* "global suspend" of the HC-to-USB interface (root hub), or
1633          * "selective suspend" of just one hub-device link.
1634          */
1635         if (!udev->parent) {
1636                 struct usb_bus  *bus = udev->bus;
1637                 if (bus && bus->op->hub_suspend) {
1638                         status = bus->op->hub_suspend (bus);
1639                         if (status == 0) {
1640                                 dev_dbg(&udev->dev, "usb suspend\n");
1641                                 usb_set_device_state(udev,
1642                                                 USB_STATE_SUSPENDED);
1643                         }
1644                 } else
1645                         status = -EOPNOTSUPP;
1646         } else
1647                 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1648                                 udev);
1649
1650         if (status == 0)
1651                 udev->dev.power.power_state = state;
1652         return status;
1653 }
1654
1655 /**
1656  * usb_suspend_device - suspend a usb device
1657  * @udev: device that's no longer in active use
1658  * @state: PMSG_SUSPEND to suspend
1659  * Context: must be able to sleep; device not locked
1660  *
1661  * Suspends a USB device that isn't in active use, conserving power.
1662  * Devices may wake out of a suspend, if anything important happens,
1663  * using the remote wakeup mechanism.  They may also be taken out of
1664  * suspend by the host, using usb_resume_device().  It's also routine
1665  * to disconnect devices while they are suspended.
1666  *
1667  * Suspending OTG devices may trigger HNP, if that's been enabled
1668  * between a pair of dual-role devices.  That will change roles, such
1669  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1670  *
1671  * Returns 0 on success, else negative errno.
1672  */
1673 int usb_suspend_device(struct usb_device *udev, pm_message_t state)
1674 {
1675         int     port1, status;
1676
1677         port1 = locktree(udev);
1678         if (port1 < 0)
1679                 return port1;
1680
1681         status = __usb_suspend_device(udev, port1, state);
1682         usb_unlock_device(udev);
1683         return status;
1684 }
1685
1686 /*
1687  * hardware resume signaling is finished, either because of selective
1688  * resume (by host) or remote wakeup (by device) ... now see what changed
1689  * in the tree that's rooted at this device.
1690  */
1691 static int finish_port_resume(struct usb_device *udev)
1692 {
1693         int     status;
1694         u16     devstatus;
1695
1696         /* caller owns the udev device lock */
1697         dev_dbg(&udev->dev, "usb resume\n");
1698
1699         /* usb ch9 identifies four variants of SUSPENDED, based on what
1700          * state the device resumes to.  Linux currently won't see the
1701          * first two on the host side; they'd be inside hub_port_init()
1702          * during many timeouts, but khubd can't suspend until later.
1703          */
1704         usb_set_device_state(udev, udev->actconfig
1705                         ? USB_STATE_CONFIGURED
1706                         : USB_STATE_ADDRESS);
1707         udev->dev.power.power_state = PMSG_ON;
1708
1709         /* 10.5.4.5 says be sure devices in the tree are still there.
1710          * For now let's assume the device didn't go crazy on resume,
1711          * and device drivers will know about any resume quirks.
1712          */
1713         status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1714         if (status < 0)
1715                 dev_dbg(&udev->dev,
1716                         "gone after usb resume? status %d\n",
1717                         status);
1718         else if (udev->actconfig) {
1719                 unsigned        i;
1720
1721                 le16_to_cpus(&devstatus);
1722                 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
1723                         status = usb_control_msg(udev,
1724                                         usb_sndctrlpipe(udev, 0),
1725                                         USB_REQ_CLEAR_FEATURE,
1726                                                 USB_RECIP_DEVICE,
1727                                         USB_DEVICE_REMOTE_WAKEUP, 0,
1728                                         NULL, 0,
1729                                         USB_CTRL_SET_TIMEOUT);
1730                         if (status) {
1731                                 dev_dbg(&udev->dev, "disable remote "
1732                                         "wakeup, status %d\n", status);
1733                                 status = 0;
1734                         }
1735                 }
1736
1737                 /* resume interface drivers; if this is a hub, it
1738                  * resumes the child devices
1739                  */
1740                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1741                         struct usb_interface    *intf;
1742                         struct usb_driver       *driver;
1743
1744                         intf = udev->actconfig->interface[i];
1745                         if (is_active(intf))
1746                                 continue;
1747                         if (!intf->dev.driver) {
1748                                 /* FIXME maybe force to alt 0 */
1749                                 continue;
1750                         }
1751                         driver = to_usb_driver(intf->dev.driver);
1752
1753                         /* bus_rescan_devices() may rebind drivers */
1754                         if (!driver->resume)
1755                                 continue;
1756
1757                         /* can we do better than just logging errors? */
1758                         mark_active(intf);
1759                         status = driver->resume(intf);
1760                         if (status < 0) {
1761                                 mark_quiesced(intf);
1762                                 dev_dbg(&intf->dev,
1763                                         "resume error %d\n",
1764                                         status);
1765                         }
1766                 }
1767                 status = 0;
1768
1769         } else if (udev->devnum <= 0) {
1770                 dev_dbg(&udev->dev, "bogus resume!\n");
1771                 status = -EINVAL;
1772         }
1773         return status;
1774 }
1775
1776 static int
1777 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1778 {
1779         int     status;
1780
1781         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1782
1783         /* see 7.1.7.7; affects power usage, but not budgeting */
1784         status = clear_port_feature(hub->hdev,
1785                         port1, USB_PORT_FEAT_SUSPEND);
1786         if (status) {
1787                 dev_dbg(hub->intfdev,
1788                         "can't resume port %d, status %d\n",
1789                         port1, status);
1790         } else {
1791                 u16             devstatus;
1792                 u16             portchange;
1793
1794                 /* drive resume for at least 20 msec */
1795                 if (udev)
1796                         dev_dbg(&udev->dev, "RESUME\n");
1797                 msleep(25);
1798
1799 #define LIVE_FLAGS      ( USB_PORT_STAT_POWER \
1800                         | USB_PORT_STAT_ENABLE \
1801                         | USB_PORT_STAT_CONNECTION)
1802
1803                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1804                  * stop resume signaling.  Then finish the resume
1805                  * sequence.
1806                  */
1807                 devstatus = portchange = 0;
1808                 status = hub_port_status(hub, port1,
1809                                 &devstatus, &portchange);
1810                 if (status < 0
1811                                 || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
1812                                 || (devstatus & USB_PORT_STAT_SUSPEND) != 0
1813                                 ) {
1814                         dev_dbg(hub->intfdev,
1815                                 "port %d status %04x.%04x after resume, %d\n",
1816                                 port1, portchange, devstatus, status);
1817                 } else {
1818                         /* TRSMRCY = 10 msec */
1819                         msleep(10);
1820                         if (udev)
1821                                 status = finish_port_resume(udev);
1822                 }
1823         }
1824         if (status < 0)
1825                 hub_port_logical_disconnect(hub, port1);
1826
1827         return status;
1828 }
1829
1830 static int hub_resume (struct usb_interface *intf);
1831
1832 /**
1833  * usb_resume_device - re-activate a suspended usb device
1834  * @udev: device to re-activate
1835  * Context: must be able to sleep; device not locked
1836  *
1837  * This will re-activate the suspended device, increasing power usage
1838  * while letting drivers communicate again with its endpoints.
1839  * USB resume explicitly guarantees that the power session between
1840  * the host and the device is the same as it was when the device
1841  * suspended.
1842  *
1843  * Returns 0 on success, else negative errno.
1844  */
1845 int usb_resume_device(struct usb_device *udev)
1846 {
1847         int     port1, status;
1848
1849         port1 = locktree(udev);
1850         if (port1 < 0)
1851                 return port1;
1852
1853         /* "global resume" of the HC-to-USB interface (root hub), or
1854          * selective resume of one hub-to-device port
1855          */
1856         if (!udev->parent) {
1857                 struct usb_bus  *bus = udev->bus;
1858                 if (bus && bus->op->hub_resume) {
1859                         status = bus->op->hub_resume (bus);
1860                 } else
1861                         status = -EOPNOTSUPP;
1862                 if (status == 0) {
1863                         dev_dbg(&udev->dev, "usb resume\n");
1864                         /* TRSMRCY = 10 msec */
1865                         msleep(10);
1866                         usb_set_device_state (udev, USB_STATE_CONFIGURED);
1867                         udev->dev.power.power_state = PMSG_ON;
1868                         status = hub_resume (udev
1869                                         ->actconfig->interface[0]);
1870                 }
1871         } else if (udev->state == USB_STATE_SUSPENDED) {
1872                 // NOTE this fails if parent is also suspended...
1873                 status = hub_port_resume(hdev_to_hub(udev->parent),
1874                                 port1, udev);
1875         } else {
1876                 status = 0;
1877         }
1878         if (status < 0) {
1879                 dev_dbg(&udev->dev, "can't resume, status %d\n",
1880                         status);
1881         }
1882
1883         usb_unlock_device(udev);
1884
1885         /* rebind drivers that had no suspend() */
1886         if (status == 0) {
1887                 usb_lock_all_devices();
1888                 bus_rescan_devices(&usb_bus_type);
1889                 usb_unlock_all_devices();
1890         }
1891         return status;
1892 }
1893
1894 static int remote_wakeup(struct usb_device *udev)
1895 {
1896         int     status = 0;
1897
1898         /* don't repeat RESUME sequence if this device
1899          * was already woken up by some other task
1900          */
1901         down(&udev->serialize);
1902         if (udev->state == USB_STATE_SUSPENDED) {
1903                 dev_dbg(&udev->dev, "RESUME (wakeup)\n");
1904                 /* TRSMRCY = 10 msec */
1905                 msleep(10);
1906                 status = finish_port_resume(udev);
1907         }
1908         up(&udev->serialize);
1909         return status;
1910 }
1911
1912 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
1913 {
1914         struct usb_hub          *hub = usb_get_intfdata (intf);
1915         struct usb_device       *hdev = hub->hdev;
1916         unsigned                port1;
1917
1918         /* fail if children aren't already suspended */
1919         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1920                 struct usb_device       *udev;
1921
1922                 udev = hdev->children [port1-1];
1923                 if (udev && udev->state != USB_STATE_SUSPENDED) {
1924                         dev_dbg(&intf->dev, "port %d nyet suspended\n", port1);
1925                         return -EBUSY;
1926                 }
1927         }
1928
1929         /* stop khubd and related activity */
1930         hub_quiesce(hub);
1931         return 0;
1932 }
1933
1934 static int hub_resume(struct usb_interface *intf)
1935 {
1936         struct usb_device       *hdev = interface_to_usbdev(intf);
1937         struct usb_hub          *hub = usb_get_intfdata (intf);
1938         unsigned                port1;
1939         int                     status;
1940
1941         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1942                 struct usb_device       *udev;
1943                 u16                     portstat, portchange;
1944
1945                 udev = hdev->children [port1-1];
1946                 status = hub_port_status(hub, port1, &portstat, &portchange);
1947                 if (status == 0) {
1948                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
1949                                 clear_port_feature(hdev, port1,
1950                                         USB_PORT_FEAT_C_SUSPEND);
1951                                 portchange &= ~USB_PORT_STAT_C_SUSPEND;
1952                         }
1953
1954                         /* let khubd handle disconnects etc */
1955                         if (portchange)
1956                                 continue;
1957                 }
1958
1959                 if (!udev || status < 0)
1960                         continue;
1961                 down (&udev->serialize);
1962                 if (portstat & USB_PORT_STAT_SUSPEND)
1963                         status = hub_port_resume(hub, port1, udev);
1964                 else {
1965                         status = finish_port_resume(udev);
1966                         if (status < 0) {
1967                                 dev_dbg(&intf->dev, "resume port %d --> %d\n",
1968                                         port1, status);
1969                                 hub_port_logical_disconnect(hub, port1);
1970                         }
1971                 }
1972                 up(&udev->serialize);
1973         }
1974         hub->resume_root_hub = 0;
1975         hub_activate(hub);
1976         return 0;
1977 }
1978
1979 void usb_resume_root_hub(struct usb_device *hdev)
1980 {
1981         struct usb_hub *hub = hdev_to_hub(hdev);
1982
1983         hub->resume_root_hub = 1;
1984         kick_khubd(hub);
1985 }
1986
1987 #else   /* !CONFIG_USB_SUSPEND */
1988
1989 int usb_suspend_device(struct usb_device *udev, pm_message_t state)
1990 {
1991         return 0;
1992 }
1993
1994 int usb_resume_device(struct usb_device *udev)
1995 {
1996         return 0;
1997 }
1998
1999 #define hub_suspend             NULL
2000 #define hub_resume              NULL
2001 #define remote_wakeup(x)        0
2002
2003 #endif  /* CONFIG_USB_SUSPEND */
2004
2005 EXPORT_SYMBOL(usb_suspend_device);
2006 EXPORT_SYMBOL(usb_resume_device);
2007
2008
2009
2010 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2011  *
2012  * Between connect detection and reset signaling there must be a delay
2013  * of 100ms at least for debounce and power-settling.  The corresponding
2014  * timer shall restart whenever the downstream port detects a disconnect.
2015  *
2016  * Apparently there are some bluetooth and irda-dongles and a number of
2017  * low-speed devices for which this debounce period may last over a second.
2018  * Not covered by the spec - but easy to deal with.
2019  *
2020  * This implementation uses a 1500ms total debounce timeout; if the
2021  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
2022  * every 25ms for transient disconnects.  When the port status has been
2023  * unchanged for 100ms it returns the port status.
2024  */
2025
2026 #define HUB_DEBOUNCE_TIMEOUT    1500
2027 #define HUB_DEBOUNCE_STEP         25
2028 #define HUB_DEBOUNCE_STABLE      100
2029
2030 static int hub_port_debounce(struct usb_hub *hub, int port1)
2031 {
2032         int ret;
2033         int total_time, stable_time = 0;
2034         u16 portchange, portstatus;
2035         unsigned connection = 0xffff;
2036
2037         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2038                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2039                 if (ret < 0)
2040                         return ret;
2041
2042                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2043                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2044                         stable_time += HUB_DEBOUNCE_STEP;
2045                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2046                                 break;
2047                 } else {
2048                         stable_time = 0;
2049                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2050                 }
2051
2052                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2053                         clear_port_feature(hub->hdev, port1,
2054                                         USB_PORT_FEAT_C_CONNECTION);
2055                 }
2056
2057                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2058                         break;
2059                 msleep(HUB_DEBOUNCE_STEP);
2060         }
2061
2062         dev_dbg (hub->intfdev,
2063                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2064                 port1, total_time, stable_time, portstatus);
2065
2066         if (stable_time < HUB_DEBOUNCE_STABLE)
2067                 return -ETIMEDOUT;
2068         return portstatus;
2069 }
2070
2071 static void ep0_reinit(struct usb_device *udev)
2072 {
2073         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2074         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2075         udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2076 }
2077
2078 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2079 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2080
2081 static int hub_set_address(struct usb_device *udev)
2082 {
2083         int retval;
2084
2085         if (udev->devnum == 0)
2086                 return -EINVAL;
2087         if (udev->state == USB_STATE_ADDRESS)
2088                 return 0;
2089         if (udev->state != USB_STATE_DEFAULT)
2090                 return -EINVAL;
2091         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2092                 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2093                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2094         if (retval == 0) {
2095                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2096                 ep0_reinit(udev);
2097         }
2098         return retval;
2099 }
2100
2101 /* Reset device, (re)assign address, get device descriptor.
2102  * Device connection must be stable, no more debouncing needed.
2103  * Returns device in USB_STATE_ADDRESS, except on error.
2104  *
2105  * If this is called for an already-existing device (as part of
2106  * usb_reset_device), the caller must own the device lock.  For a
2107  * newly detected device that is not accessible through any global
2108  * pointers, it's not necessary to lock the device.
2109  */
2110 static int
2111 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2112                 int retry_counter)
2113 {
2114         static DECLARE_MUTEX(usb_address0_sem);
2115
2116         struct usb_device       *hdev = hub->hdev;
2117         int                     i, j, retval;
2118         unsigned                delay = HUB_SHORT_RESET_TIME;
2119         enum usb_device_speed   oldspeed = udev->speed;
2120
2121         /* root hub ports have a slightly longer reset period
2122          * (from USB 2.0 spec, section 7.1.7.5)
2123          */
2124         if (!hdev->parent) {
2125                 delay = HUB_ROOT_RESET_TIME;
2126                 if (port1 == hdev->bus->otg_port)
2127                         hdev->bus->b_hnp_enable = 0;
2128         }
2129
2130         /* Some low speed devices have problems with the quick delay, so */
2131         /*  be a bit pessimistic with those devices. RHbug #23670 */
2132         if (oldspeed == USB_SPEED_LOW)
2133                 delay = HUB_LONG_RESET_TIME;
2134
2135         down(&usb_address0_sem);
2136
2137         /* Reset the device; full speed may morph to high speed */
2138         retval = hub_port_reset(hub, port1, udev, delay);
2139         if (retval < 0)         /* error or disconnect */
2140                 goto fail;
2141                                 /* success, speed is known */
2142         retval = -ENODEV;
2143
2144         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2145                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2146                 goto fail;
2147         }
2148         oldspeed = udev->speed;
2149
2150         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2151          * it's fixed size except for full speed devices.
2152          */
2153         switch (udev->speed) {
2154         case USB_SPEED_HIGH:            /* fixed at 64 */
2155                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2156                 break;
2157         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2158                 /* to determine the ep0 maxpacket size, try to read
2159                  * the device descriptor to get bMaxPacketSize0 and
2160                  * then correct our initial guess.
2161                  */
2162                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2163                 break;
2164         case USB_SPEED_LOW:             /* fixed at 8 */
2165                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2166                 break;
2167         default:
2168                 goto fail;
2169         }
2170
2171         dev_info (&udev->dev,
2172                         "%s %s speed USB device using %s and address %d\n",
2173                         (udev->config) ? "reset" : "new",
2174                         ({ char *speed; switch (udev->speed) {
2175                         case USB_SPEED_LOW:     speed = "low";  break;
2176                         case USB_SPEED_FULL:    speed = "full"; break;
2177                         case USB_SPEED_HIGH:    speed = "high"; break;
2178                         default:                speed = "?";    break;
2179                         }; speed;}),
2180                         udev->bus->controller->driver->name,
2181                         udev->devnum);
2182
2183         /* Set up TT records, if needed  */
2184         if (hdev->tt) {
2185                 udev->tt = hdev->tt;
2186                 udev->ttport = hdev->ttport;
2187         } else if (udev->speed != USB_SPEED_HIGH
2188                         && hdev->speed == USB_SPEED_HIGH) {
2189                 udev->tt = &hub->tt;
2190                 udev->ttport = port1;
2191         }
2192
2193         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2194          * Because device hardware and firmware is sometimes buggy in
2195          * this area, and this is how Linux has done it for ages.
2196          * Change it cautiously.
2197          *
2198          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2199          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2200          * so it may help with some non-standards-compliant devices.
2201          * Otherwise we start with SET_ADDRESS and then try to read the
2202          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2203          * value.
2204          */
2205         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2206                 if (USE_NEW_SCHEME(retry_counter)) {
2207                         struct usb_device_descriptor *buf;
2208                         int r = 0;
2209
2210 #define GET_DESCRIPTOR_BUFSIZE  64
2211                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2212                         if (!buf) {
2213                                 retval = -ENOMEM;
2214                                 continue;
2215                         }
2216
2217                         /* Use a short timeout the first time through,
2218                          * so that recalcitrant full-speed devices with
2219                          * 8- or 16-byte ep0-maxpackets won't slow things
2220                          * down tremendously by NAKing the unexpectedly
2221                          * early status stage.  Also, retry on all errors;
2222                          * some devices are flakey.
2223                          */
2224                         for (j = 0; j < 3; ++j) {
2225                                 buf->bMaxPacketSize0 = 0;
2226                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2227                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2228                                         USB_DT_DEVICE << 8, 0,
2229                                         buf, GET_DESCRIPTOR_BUFSIZE,
2230                                         (i ? USB_CTRL_GET_TIMEOUT : 1000));
2231                                 switch (buf->bMaxPacketSize0) {
2232                                 case 8: case 16: case 32: case 64:
2233                                         if (buf->bDescriptorType ==
2234                                                         USB_DT_DEVICE) {
2235                                                 r = 0;
2236                                                 break;
2237                                         }
2238                                         /* FALL THROUGH */
2239                                 default:
2240                                         if (r == 0)
2241                                                 r = -EPROTO;
2242                                         break;
2243                                 }
2244                                 if (r == 0)
2245                                         break;
2246                         }
2247                         udev->descriptor.bMaxPacketSize0 =
2248                                         buf->bMaxPacketSize0;
2249                         kfree(buf);
2250
2251                         retval = hub_port_reset(hub, port1, udev, delay);
2252                         if (retval < 0)         /* error or disconnect */
2253                                 goto fail;
2254                         if (oldspeed != udev->speed) {
2255                                 dev_dbg(&udev->dev,
2256                                         "device reset changed speed!\n");
2257                                 retval = -ENODEV;
2258                                 goto fail;
2259                         }
2260                         if (r) {
2261                                 dev_err(&udev->dev, "device descriptor "
2262                                                 "read/%s, error %d\n",
2263                                                 "64", r);
2264                                 retval = -EMSGSIZE;
2265                                 continue;
2266                         }
2267 #undef GET_DESCRIPTOR_BUFSIZE
2268                 }
2269
2270                 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2271                         retval = hub_set_address(udev);
2272                         if (retval >= 0)
2273                                 break;
2274                         msleep(200);
2275                 }
2276                 if (retval < 0) {
2277                         dev_err(&udev->dev,
2278                                 "device not accepting address %d, error %d\n",
2279                                 udev->devnum, retval);
2280                         goto fail;
2281                 }
2282
2283                 /* cope with hardware quirkiness:
2284                  *  - let SET_ADDRESS settle, some device hardware wants it
2285                  *  - read ep0 maxpacket even for high and low speed,
2286                  */
2287                 msleep(10);
2288                 if (USE_NEW_SCHEME(retry_counter))
2289                         break;
2290
2291                 retval = usb_get_device_descriptor(udev, 8);
2292                 if (retval < 8) {
2293                         dev_err(&udev->dev, "device descriptor "
2294                                         "read/%s, error %d\n",
2295                                         "8", retval);
2296                         if (retval >= 0)
2297                                 retval = -EMSGSIZE;
2298                 } else {
2299                         retval = 0;
2300                         break;
2301                 }
2302         }
2303         if (retval)
2304                 goto fail;
2305
2306         i = udev->descriptor.bMaxPacketSize0;
2307         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2308                 if (udev->speed != USB_SPEED_FULL ||
2309                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2310                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2311                         retval = -EMSGSIZE;
2312                         goto fail;
2313                 }
2314                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2315                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2316                 ep0_reinit(udev);
2317         }
2318
2319         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2320         if (retval < (signed)sizeof(udev->descriptor)) {
2321                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2322                         "all", retval);
2323                 if (retval >= 0)
2324                         retval = -ENOMSG;
2325                 goto fail;
2326         }
2327
2328         retval = 0;
2329
2330 fail:
2331         if (retval)
2332                 hub_port_disable(hub, port1, 0);
2333         up(&usb_address0_sem);
2334         return retval;
2335 }
2336
2337 static void
2338 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2339 {
2340         struct usb_qualifier_descriptor *qual;
2341         int                             status;
2342
2343         qual = kmalloc (sizeof *qual, SLAB_KERNEL);
2344         if (qual == NULL)
2345                 return;
2346
2347         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2348                         qual, sizeof *qual);
2349         if (status == sizeof *qual) {
2350                 dev_info(&udev->dev, "not running at top speed; "
2351                         "connect to a high speed hub\n");
2352                 /* hub LEDs are probably harder to miss than syslog */
2353                 if (hub->has_indicators) {
2354                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2355                         schedule_work (&hub->leds);
2356                 }
2357         }
2358         kfree(qual);
2359 }
2360
2361 static unsigned
2362 hub_power_remaining (struct usb_hub *hub)
2363 {
2364         struct usb_device *hdev = hub->hdev;
2365         int remaining;
2366         unsigned i;
2367
2368         remaining = hub->power_budget;
2369         if (!remaining)         /* self-powered */
2370                 return 0;
2371
2372         for (i = 0; i < hdev->maxchild; i++) {
2373                 struct usb_device       *udev = hdev->children[i];
2374                 int                     delta, ceiling;
2375
2376                 if (!udev)
2377                         continue;
2378
2379                 /* 100mA per-port ceiling, or 8mA for OTG ports */
2380                 if (i != (udev->bus->otg_port - 1) || hdev->parent)
2381                         ceiling = 50;
2382                 else
2383                         ceiling = 4;
2384
2385                 if (udev->actconfig)
2386                         delta = udev->actconfig->desc.bMaxPower;
2387                 else
2388                         delta = ceiling;
2389                 // dev_dbg(&udev->dev, "budgeted %dmA\n", 2 * delta);
2390                 if (delta > ceiling)
2391                         dev_warn(&udev->dev, "%dmA over %dmA budget!\n",
2392                                 2 * (delta - ceiling), 2 * ceiling);
2393                 remaining -= delta;
2394         }
2395         if (remaining < 0) {
2396                 dev_warn(hub->intfdev,
2397                         "%dmA over power budget!\n",
2398                         -2 * remaining);
2399                 remaining = 0;
2400         }
2401         return remaining;
2402 }
2403
2404 /* Handle physical or logical connection change events.
2405  * This routine is called when:
2406  *      a port connection-change occurs;
2407  *      a port enable-change occurs (often caused by EMI);
2408  *      usb_reset_device() encounters changed descriptors (as from
2409  *              a firmware download)
2410  * caller already locked the hub
2411  */
2412 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2413                                         u16 portstatus, u16 portchange)
2414 {
2415         struct usb_device *hdev = hub->hdev;
2416         struct device *hub_dev = hub->intfdev;
2417         int status, i;
2418
2419         dev_dbg (hub_dev,
2420                 "port %d, status %04x, change %04x, %s\n",
2421                 port1, portstatus, portchange, portspeed (portstatus));
2422
2423         if (hub->has_indicators) {
2424                 set_port_led(hub, port1, HUB_LED_AUTO);
2425                 hub->indicator[port1-1] = INDICATOR_AUTO;
2426         }
2427
2428         /* Disconnect any existing devices under this port */
2429         if (hdev->children[port1-1])
2430                 usb_disconnect(&hdev->children[port1-1]);
2431         clear_bit(port1, hub->change_bits);
2432
2433 #ifdef  CONFIG_USB_OTG
2434         /* during HNP, don't repeat the debounce */
2435         if (hdev->bus->is_b_host)
2436                 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2437 #endif
2438
2439         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2440                 status = hub_port_debounce(hub, port1);
2441                 if (status < 0) {
2442                         dev_err (hub_dev,
2443                                 "connect-debounce failed, port %d disabled\n",
2444                                 port1);
2445                         goto done;
2446                 }
2447                 portstatus = status;
2448         }
2449
2450         /* Return now if nothing is connected */
2451         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2452
2453                 /* maybe switch power back on (e.g. root hub was reset) */
2454                 if ((hub->descriptor->wHubCharacteristics
2455                                         & HUB_CHAR_LPSM) < 2
2456                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2457                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2458
2459                 if (portstatus & USB_PORT_STAT_ENABLE)
2460                         goto done;
2461                 return;
2462         }
2463
2464 #ifdef  CONFIG_USB_SUSPEND
2465         /* If something is connected, but the port is suspended, wake it up. */
2466         if (portstatus & USB_PORT_STAT_SUSPEND) {
2467                 status = hub_port_resume(hub, port1, NULL);
2468                 if (status < 0) {
2469                         dev_dbg(hub_dev,
2470                                 "can't clear suspend on port %d; %d\n",
2471                                 port1, status);
2472                         goto done;
2473                 }
2474         }
2475 #endif
2476
2477         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2478                 struct usb_device *udev;
2479
2480                 /* reallocate for each attempt, since references
2481                  * to the previous one can escape in various ways
2482                  */
2483                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2484                 if (!udev) {
2485                         dev_err (hub_dev,
2486                                 "couldn't allocate port %d usb_device\n",
2487                                 port1);
2488                         goto done;
2489                 }
2490
2491                 usb_set_device_state(udev, USB_STATE_POWERED);
2492                 udev->speed = USB_SPEED_UNKNOWN;
2493
2494                 /* set the address */
2495                 choose_address(udev);
2496                 if (udev->devnum <= 0) {
2497                         status = -ENOTCONN;     /* Don't retry */
2498                         goto loop;
2499                 }
2500
2501                 /* reset and get descriptor */
2502                 status = hub_port_init(hub, udev, port1, i);
2503                 if (status < 0)
2504                         goto loop;
2505
2506                 /* consecutive bus-powered hubs aren't reliable; they can
2507                  * violate the voltage drop budget.  if the new child has
2508                  * a "powered" LED, users should notice we didn't enable it
2509                  * (without reading syslog), even without per-port LEDs
2510                  * on the parent.
2511                  */
2512                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2513                                 && hub->power_budget) {
2514                         u16     devstat;
2515
2516                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2517                                         &devstat);
2518                         if (status < 0) {
2519                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2520                                 goto loop_disable;
2521                         }
2522                         cpu_to_le16s(&devstat);
2523                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2524                                 dev_err(&udev->dev,
2525                                         "can't connect bus-powered hub "
2526                                         "to this port\n");
2527                                 if (hub->has_indicators) {
2528                                         hub->indicator[port1-1] =
2529                                                 INDICATOR_AMBER_BLINK;
2530                                         schedule_work (&hub->leds);
2531                                 }
2532                                 status = -ENOTCONN;     /* Don't retry */
2533                                 goto loop_disable;
2534                         }
2535                 }
2536
2537                 /* check for devices running slower than they could */
2538                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2539                                 && udev->speed == USB_SPEED_FULL
2540                                 && highspeed_hubs != 0)
2541                         check_highspeed (hub, udev, port1);
2542
2543                 /* Store the parent's children[] pointer.  At this point
2544                  * udev becomes globally accessible, although presumably
2545                  * no one will look at it until hdev is unlocked.
2546                  */
2547                 down (&udev->serialize);
2548                 status = 0;
2549
2550                 /* We mustn't add new devices if the parent hub has
2551                  * been disconnected; we would race with the
2552                  * recursively_mark_NOTATTACHED() routine.
2553                  */
2554                 spin_lock_irq(&device_state_lock);
2555                 if (hdev->state == USB_STATE_NOTATTACHED)
2556                         status = -ENOTCONN;
2557                 else
2558                         hdev->children[port1-1] = udev;
2559                 spin_unlock_irq(&device_state_lock);
2560
2561                 /* Run it through the hoops (find a driver, etc) */
2562                 if (!status) {
2563                         status = usb_new_device(udev);
2564                         if (status) {
2565                                 spin_lock_irq(&device_state_lock);
2566                                 hdev->children[port1-1] = NULL;
2567                                 spin_unlock_irq(&device_state_lock);
2568                         }
2569                 }
2570
2571                 up (&udev->serialize);
2572                 if (status)
2573                         goto loop_disable;
2574
2575                 status = hub_power_remaining(hub);
2576                 if (status)
2577                         dev_dbg(hub_dev,
2578                                 "%dmA power budget left\n",
2579                                 2 * status);
2580
2581                 return;
2582
2583 loop_disable:
2584                 hub_port_disable(hub, port1, 1);
2585 loop:
2586                 ep0_reinit(udev);
2587                 release_address(udev);
2588                 usb_put_dev(udev);
2589                 if (status == -ENOTCONN)
2590                         break;
2591         }
2592
2593 done:
2594         hub_port_disable(hub, port1, 1);
2595 }
2596
2597 static void hub_events(void)
2598 {
2599         struct list_head *tmp;
2600         struct usb_device *hdev;
2601         struct usb_interface *intf;
2602         struct usb_hub *hub;
2603         struct device *hub_dev;
2604         u16 hubstatus;
2605         u16 hubchange;
2606         u16 portstatus;
2607         u16 portchange;
2608         int i, ret;
2609         int connect_change;
2610
2611         /*
2612          *  We restart the list every time to avoid a deadlock with
2613          * deleting hubs downstream from this one. This should be
2614          * safe since we delete the hub from the event list.
2615          * Not the most efficient, but avoids deadlocks.
2616          */
2617         while (1) {
2618
2619                 /* Grab the first entry at the beginning of the list */
2620                 spin_lock_irq(&hub_event_lock);
2621                 if (list_empty(&hub_event_list)) {
2622                         spin_unlock_irq(&hub_event_lock);
2623                         break;
2624                 }
2625
2626                 tmp = hub_event_list.next;
2627                 list_del_init(tmp);
2628
2629                 hub = list_entry(tmp, struct usb_hub, event_list);
2630                 hdev = hub->hdev;
2631                 intf = to_usb_interface(hub->intfdev);
2632                 hub_dev = &intf->dev;
2633
2634                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
2635                                 hdev->state, hub->descriptor
2636                                         ? hub->descriptor->bNbrPorts
2637                                         : 0,
2638                                 /* NOTE: expects max 15 ports... */
2639                                 (u16) hub->change_bits[0],
2640                                 (u16) hub->event_bits[0]);
2641
2642                 usb_get_intf(intf);
2643                 i = hub->resume_root_hub;
2644                 spin_unlock_irq(&hub_event_lock);
2645
2646                 /* Is this is a root hub wanting to be resumed? */
2647                 if (i)
2648                         usb_resume_device(hdev);
2649
2650                 /* Lock the device, then check to see if we were
2651                  * disconnected while waiting for the lock to succeed. */
2652                 if (locktree(hdev) < 0) {
2653                         usb_put_intf(intf);
2654                         continue;
2655                 }
2656                 if (hub != usb_get_intfdata(intf))
2657                         goto loop;
2658
2659                 /* If the hub has died, clean up after it */
2660                 if (hdev->state == USB_STATE_NOTATTACHED) {
2661                         hub_pre_reset(hub);
2662                         goto loop;
2663                 }
2664
2665                 /* If this is an inactive or suspended hub, do nothing */
2666                 if (hub->quiescing)
2667                         goto loop;
2668
2669                 if (hub->error) {
2670                         dev_dbg (hub_dev, "resetting for error %d\n",
2671                                 hub->error);
2672
2673                         ret = usb_reset_device(hdev);
2674                         if (ret) {
2675                                 dev_dbg (hub_dev,
2676                                         "error resetting hub: %d\n", ret);
2677                                 goto loop;
2678                         }
2679
2680                         hub->nerrors = 0;
2681                         hub->error = 0;
2682                 }
2683
2684                 /* deal with port status changes */
2685                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2686                         if (test_bit(i, hub->busy_bits))
2687                                 continue;
2688                         connect_change = test_bit(i, hub->change_bits);
2689                         if (!test_and_clear_bit(i, hub->event_bits) &&
2690                                         !connect_change && !hub->activating)
2691                                 continue;
2692
2693                         ret = hub_port_status(hub, i,
2694                                         &portstatus, &portchange);
2695                         if (ret < 0)
2696                                 continue;
2697
2698                         if (hub->activating && !hdev->children[i-1] &&
2699                                         (portstatus &
2700                                                 USB_PORT_STAT_CONNECTION))
2701                                 connect_change = 1;
2702
2703                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2704                                 clear_port_feature(hdev, i,
2705                                         USB_PORT_FEAT_C_CONNECTION);
2706                                 connect_change = 1;
2707                         }
2708
2709                         if (portchange & USB_PORT_STAT_C_ENABLE) {
2710                                 if (!connect_change)
2711                                         dev_dbg (hub_dev,
2712                                                 "port %d enable change, "
2713                                                 "status %08x\n",
2714                                                 i, portstatus);
2715                                 clear_port_feature(hdev, i,
2716                                         USB_PORT_FEAT_C_ENABLE);
2717
2718                                 /*
2719                                  * EM interference sometimes causes badly
2720                                  * shielded USB devices to be shutdown by
2721                                  * the hub, this hack enables them again.
2722                                  * Works at least with mouse driver.
2723                                  */
2724                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
2725                                     && !connect_change
2726                                     && hdev->children[i-1]) {
2727                                         dev_err (hub_dev,
2728                                             "port %i "
2729                                             "disabled by hub (EMI?), "
2730                                             "re-enabling...\n",
2731                                                 i);
2732                                         connect_change = 1;
2733                                 }
2734                         }
2735
2736                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2737                                 clear_port_feature(hdev, i,
2738                                         USB_PORT_FEAT_C_SUSPEND);
2739                                 if (hdev->children[i-1]) {
2740                                         ret = remote_wakeup(hdev->
2741                                                         children[i-1]);
2742                                         if (ret < 0)
2743                                                 connect_change = 1;
2744                                 } else {
2745                                         ret = -ENODEV;
2746                                         hub_port_disable(hub, i, 1);
2747                                 }
2748                                 dev_dbg (hub_dev,
2749                                         "resume on port %d, status %d\n",
2750                                         i, ret);
2751                         }
2752
2753                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2754                                 dev_err (hub_dev,
2755                                         "over-current change on port %d\n",
2756                                         i);
2757                                 clear_port_feature(hdev, i,
2758                                         USB_PORT_FEAT_C_OVER_CURRENT);
2759                                 hub_power_on(hub);
2760                         }
2761
2762                         if (portchange & USB_PORT_STAT_C_RESET) {
2763                                 dev_dbg (hub_dev,
2764                                         "reset change on port %d\n",
2765                                         i);
2766                                 clear_port_feature(hdev, i,
2767                                         USB_PORT_FEAT_C_RESET);
2768                         }
2769
2770                         if (connect_change)
2771                                 hub_port_connect_change(hub, i,
2772                                                 portstatus, portchange);
2773                 } /* end for i */
2774
2775                 /* deal with hub status changes */
2776                 if (test_and_clear_bit(0, hub->event_bits) == 0)
2777                         ;       /* do nothing */
2778                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2779                         dev_err (hub_dev, "get_hub_status failed\n");
2780                 else {
2781                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2782                                 dev_dbg (hub_dev, "power change\n");
2783                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2784                         }
2785                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
2786                                 dev_dbg (hub_dev, "overcurrent change\n");
2787                                 msleep(500);    /* Cool down */
2788                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2789                                 hub_power_on(hub);
2790                         }
2791                 }
2792
2793                 hub->activating = 0;
2794
2795                 /* If this is a root hub, tell the HCD it's okay to
2796                  * re-enable port-change interrupts now. */
2797                 if (!hdev->parent)
2798                         usb_enable_root_hub_irq(hdev->bus);
2799
2800 loop:
2801                 usb_unlock_device(hdev);
2802                 usb_put_intf(intf);
2803
2804         } /* end while (1) */
2805 }
2806
2807 static int hub_thread(void *__unused)
2808 {
2809         do {
2810                 hub_events();
2811                 wait_event_interruptible(khubd_wait,
2812                                 !list_empty(&hub_event_list) ||
2813                                 kthread_should_stop());
2814                 try_to_freeze();
2815         } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2816
2817         pr_debug("%s: khubd exiting\n", usbcore_name);
2818         return 0;
2819 }
2820
2821 static struct usb_device_id hub_id_table [] = {
2822     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2823       .bDeviceClass = USB_CLASS_HUB},
2824     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2825       .bInterfaceClass = USB_CLASS_HUB},
2826     { }                                         /* Terminating entry */
2827 };
2828
2829 MODULE_DEVICE_TABLE (usb, hub_id_table);
2830
2831 static struct usb_driver hub_driver = {
2832         .owner =        THIS_MODULE,
2833         .name =         "hub",
2834         .probe =        hub_probe,
2835         .disconnect =   hub_disconnect,
2836         .suspend =      hub_suspend,
2837         .resume =       hub_resume,
2838         .ioctl =        hub_ioctl,
2839         .id_table =     hub_id_table,
2840 };
2841
2842 int usb_hub_init(void)
2843 {
2844         if (usb_register(&hub_driver) < 0) {
2845                 printk(KERN_ERR "%s: can't register hub driver\n",
2846                         usbcore_name);
2847                 return -1;
2848         }
2849
2850         khubd_task = kthread_run(hub_thread, NULL, "khubd");
2851         if (!IS_ERR(khubd_task))
2852                 return 0;
2853
2854         /* Fall through if kernel_thread failed */
2855         usb_deregister(&hub_driver);
2856         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2857
2858         return -1;
2859 }
2860
2861 void usb_hub_cleanup(void)
2862 {
2863         kthread_stop(khubd_task);
2864
2865         /*
2866          * Hub resources are freed for us by usb_deregister. It calls
2867          * usb_driver_purge on every device which in turn calls that
2868          * devices disconnect function if it is using this driver.
2869          * The hub_disconnect function takes care of releasing the
2870          * individual hub resources. -greg
2871          */
2872         usb_deregister(&hub_driver);
2873 } /* usb_hub_cleanup() */
2874
2875 static int config_descriptors_changed(struct usb_device *udev)
2876 {
2877         unsigned                        index;
2878         unsigned                        len = 0;
2879         struct usb_config_descriptor    *buf;
2880
2881         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2882                 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2883                         len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2884         }
2885         buf = kmalloc (len, SLAB_KERNEL);
2886         if (buf == NULL) {
2887                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2888                 /* assume the worst */
2889                 return 1;
2890         }
2891         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2892                 int length;
2893                 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2894
2895                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2896                                 old_length);
2897                 if (length < old_length) {
2898                         dev_dbg(&udev->dev, "config index %d, error %d\n",
2899                                         index, length);
2900                         break;
2901                 }
2902                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2903                                 != 0) {
2904                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2905                                 index, buf->bConfigurationValue);
2906                         break;
2907                 }
2908         }
2909         kfree(buf);
2910         return index != udev->descriptor.bNumConfigurations;
2911 }
2912
2913 /**
2914  * usb_reset_device - perform a USB port reset to reinitialize a device
2915  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2916  *
2917  * WARNING - don't reset any device unless drivers for all of its
2918  * interfaces are expecting that reset!  Maybe some driver->reset()
2919  * method should eventually help ensure sufficient cooperation.
2920  *
2921  * Do a port reset, reassign the device's address, and establish its
2922  * former operating configuration.  If the reset fails, or the device's
2923  * descriptors change from their values before the reset, or the original
2924  * configuration and altsettings cannot be restored, a flag will be set
2925  * telling khubd to pretend the device has been disconnected and then
2926  * re-connected.  All drivers will be unbound, and the device will be
2927  * re-enumerated and probed all over again.
2928  *
2929  * Returns 0 if the reset succeeded, -ENODEV if the device has been
2930  * flagged for logical disconnection, or some other negative error code
2931  * if the reset wasn't even attempted.
2932  *
2933  * The caller must own the device lock.  For example, it's safe to use
2934  * this from a driver probe() routine after downloading new firmware.
2935  * For calls that might not occur during probe(), drivers should lock
2936  * the device using usb_lock_device_for_reset().
2937  */
2938 int usb_reset_device(struct usb_device *udev)
2939 {
2940         struct usb_device               *parent_hdev = udev->parent;
2941         struct usb_hub                  *parent_hub;
2942         struct usb_device_descriptor    descriptor = udev->descriptor;
2943         struct usb_hub                  *hub = NULL;
2944         int                             i, ret = 0, port1 = -1;
2945
2946         if (udev->state == USB_STATE_NOTATTACHED ||
2947                         udev->state == USB_STATE_SUSPENDED) {
2948                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2949                                 udev->state);
2950                 return -EINVAL;
2951         }
2952
2953         if (!parent_hdev) {
2954                 /* this requires hcd-specific logic; see OHCI hc_restart() */
2955                 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2956                 return -EISDIR;
2957         }
2958
2959         for (i = 0; i < parent_hdev->maxchild; i++)
2960                 if (parent_hdev->children[i] == udev) {
2961                         port1 = i + 1;
2962                         break;
2963                 }
2964
2965         if (port1 < 0) {
2966                 /* If this ever happens, it's very bad */
2967                 dev_err(&udev->dev, "Can't locate device's port!\n");
2968                 return -ENOENT;
2969         }
2970         parent_hub = hdev_to_hub(parent_hdev);
2971
2972         /* If we're resetting an active hub, take some special actions */
2973         if (udev->actconfig &&
2974                         udev->actconfig->interface[0]->dev.driver ==
2975                                 &hub_driver.driver &&
2976                         (hub = hdev_to_hub(udev)) != NULL) {
2977                 hub_pre_reset(hub);
2978         }
2979
2980         set_bit(port1, parent_hub->busy_bits);
2981         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
2982
2983                 /* ep0 maxpacket size may change; let the HCD know about it.
2984                  * Other endpoints will be handled by re-enumeration. */
2985                 ep0_reinit(udev);
2986                 ret = hub_port_init(parent_hub, udev, port1, i);
2987                 if (ret >= 0)
2988                         break;
2989         }
2990         clear_bit(port1, parent_hub->busy_bits);
2991         if (ret < 0)
2992                 goto re_enumerate;
2993
2994         /* Device might have changed firmware (DFU or similar) */
2995         if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
2996                         || config_descriptors_changed (udev)) {
2997                 dev_info(&udev->dev, "device firmware changed\n");
2998                 udev->descriptor = descriptor;  /* for disconnect() calls */
2999                 goto re_enumerate;
3000         }
3001
3002         if (!udev->actconfig)
3003                 goto done;
3004
3005         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3006                         USB_REQ_SET_CONFIGURATION, 0,
3007                         udev->actconfig->desc.bConfigurationValue, 0,
3008                         NULL, 0, USB_CTRL_SET_TIMEOUT);
3009         if (ret < 0) {
3010                 dev_err(&udev->dev,
3011                         "can't restore configuration #%d (error=%d)\n",
3012                         udev->actconfig->desc.bConfigurationValue, ret);
3013                 goto re_enumerate;
3014         }
3015         usb_set_device_state(udev, USB_STATE_CONFIGURED);
3016
3017         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3018                 struct usb_interface *intf = udev->actconfig->interface[i];
3019                 struct usb_interface_descriptor *desc;
3020
3021                 /* set_interface resets host side toggle even
3022                  * for altsetting zero.  the interface may have no driver.
3023                  */
3024                 desc = &intf->cur_altsetting->desc;
3025                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3026                         desc->bAlternateSetting);
3027                 if (ret < 0) {
3028                         dev_err(&udev->dev, "failed to restore interface %d "
3029                                 "altsetting %d (error=%d)\n",
3030                                 desc->bInterfaceNumber,
3031                                 desc->bAlternateSetting,
3032                                 ret);
3033                         goto re_enumerate;
3034                 }
3035         }
3036
3037 done:
3038         if (hub)
3039                 hub_post_reset(hub);
3040         return 0;
3041
3042 re_enumerate:
3043         hub_port_logical_disconnect(parent_hub, port1);
3044         return -ENODEV;
3045 }