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/kernel.h>
  12 #include <linux/errno.h>
  13 #include <linux/module.h>
  14 #include <linux/moduleparam.h>
  15 #include <linux/completion.h>
  16 #include <linux/sched.h>
  17 #include <linux/list.h>
  18 #include <linux/slab.h>
  19 #include <linux/smp_lock.h>
  20 #include <linux/ioctl.h>
  21 #include <linux/usb.h>
  22 #include <linux/usbdevice_fs.h>
  23 #include <linux/kthread.h>
  24 #include <linux/mutex.h>
  25
  26 #include <asm/semaphore.h>
  27 #include <asm/uaccess.h>
  28 #include <asm/byteorder.h>
  29
  30 #include "usb.h"
  31 #include "hcd.h"
  32 #include "hub.h"
  33
  34 struct usb_hub {
  35         struct device           *intfdev;       /* the "interface" device */
  36         struct usb_device       *hdev;
  37         struct urb              *urb;           /* for interrupt polling pipe */
  38
  39         /* buffer for urb ... with extra space in case of babble */
  40         char                    (*buffer)[8];
  41         dma_addr_t              buffer_dma;     /* DMA address for buffer */
  42         union {
  43                 struct usb_hub_status   hub;
  44                 struct usb_port_status  port;
  45         }                       *status;        /* buffer for status reports */
  46
  47         int                     error;          /* last reported error */
  48         int                     nerrors;        /* track consecutive errors */
  49
  50         struct list_head        event_list;     /* hubs w/data or errs ready */
  51         unsigned long           event_bits[1];  /* status change bitmask */
  52         unsigned long           change_bits[1]; /* ports with logical connect
  53                                                         status change */
  54         unsigned long           busy_bits[1];   /* ports being reset or
  55                                                         resumed */
  56 #if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
  57 #error event_bits[] is too short!
  58 #endif
  59
  60         struct usb_hub_descriptor *descriptor;  /* class descriptor */
  61         struct usb_tt           tt;             /* Transaction Translator */
  62
  63         unsigned                mA_per_port;    /* current for each child */
  64
  65         unsigned                limited_power:1;
  66         unsigned                quiescing:1;
  67         unsigned                activating:1;
  68         unsigned                resume_root_hub:1;
  69
  70         unsigned                has_indicators:1;
  71         u8                      indicator[USB_MAXCHILDREN];
  72         struct work_struct      leds;
  73 };
  74
  75
  76 /* Protect struct usb_device->state and ->children members
  77  * Note: Both are also protected by ->dev.sem, except that ->state can
  78  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
  79 static DEFINE_SPINLOCK(device_state_lock);
  80
  81 /* khubd's worklist and its lock */
  82 static DEFINE_SPINLOCK(hub_event_lock);
  83 static LIST_HEAD(hub_event_list);       /* List of hubs needing servicing */
  84
  85 /* Wakes up khubd */
  86 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
  87
  88 static struct task_struct *khubd_task;
  89
  90 /* cycle leds on hubs that aren't blinking for attention */
  91 static int blinkenlights = 0;
  92 module_param (blinkenlights, bool, S_IRUGO);
  93 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
  94
  95 /*
  96  * As of 2.6.10 we introduce a new USB device initialization scheme which
  97  * closely resembles the way Windows works.  Hopefully it will be compatible
  98  * with a wider range of devices than the old scheme.  However some previously
  99  * working devices may start giving rise to "device not accepting address"
 100  * errors; if that happens the user can try the old scheme by adjusting the
 101  * following module parameters.
 102  *
 103  * For maximum flexibility there are two boolean parameters to control the
 104  * hub driver's behavior.  On the first initialization attempt, if the
 105  * "old_scheme_first" parameter is set then the old scheme will be used,
 106  * otherwise the new scheme is used.  If that fails and "use_both_schemes"
 107  * is set, then the driver will make another attempt, using the other scheme.
 108  */
 109 static int old_scheme_first = 0;
 110 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
 111 MODULE_PARM_DESC(old_scheme_first,
 112                  "start with the old device initialization scheme");
 113
 114 static int use_both_schemes = 1;
 115 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
 116 MODULE_PARM_DESC(use_both_schemes,
 117                 "try the other device initialization scheme if the "
 118                 "first one fails");
 119
 120
 121 #ifdef  DEBUG
 122 static inline char *portspeed (int portstatus)
 123 {
 124         if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
 125                 return "480 Mb/s";
 126         else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
 127                 return "1.5 Mb/s";
 128         else
 129                 return "12 Mb/s";
 130 }
 131 #endif
 132
 133 /* Note that hdev or one of its children must be locked! */
 134 static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
 135 {
 136         return usb_get_intfdata(hdev->actconfig->interface[0]);
 137 }
 138
 139 /* USB 2.0 spec Section 11.24.4.5 */
 140 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
 141 {
 142         int i, ret;
 143
 144         for (i = 0; i < 3; i++) {
 145                 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 146                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
 147                         USB_DT_HUB << 8, 0, data, size,
 148                         USB_CTRL_GET_TIMEOUT);
 149                 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
 150                         return ret;
 151         }
 152         return -EINVAL;
 153 }
 154
 155 /*
 156  * USB 2.0 spec Section 11.24.2.1
 157  */
 158 static int clear_hub_feature(struct usb_device *hdev, int feature)
 159 {
 160         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 161                 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
 162 }
 163
 164 /*
 165  * USB 2.0 spec Section 11.24.2.2
 166  */
 167 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
 168 {
 169         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 170                 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
 171                 NULL, 0, 1000);
 172 }
 173
 174 /*
 175  * USB 2.0 spec Section 11.24.2.13
 176  */
 177 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
 178 {
 179         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 180                 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
 181                 NULL, 0, 1000);
 182 }
 183
 184 /*
 185  * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
 186  * for info about using port indicators
 187  */
 188 static void set_port_led(
 189         struct usb_hub *hub,
 190         int port1,
 191         int selector
 192 )
 193 {
 194         int status = set_port_feature(hub->hdev, (selector << 8) | port1,
 195                         USB_PORT_FEAT_INDICATOR);
 196         if (status < 0)
 197                 dev_dbg (hub->intfdev,
 198                         "port %d indicator %s status %d\n",
 199                         port1,
 200                         ({ char *s; switch (selector) {
 201                         case HUB_LED_AMBER: s = "amber"; break;
 202                         case HUB_LED_GREEN: s = "green"; break;
 203                         case HUB_LED_OFF: s = "off"; break;
 204                         case HUB_LED_AUTO: s = "auto"; break;
 205                         default: s = "??"; break;
 206                         }; s; }),
 207                         status);
 208 }
 209
 210 #define LED_CYCLE_PERIOD        ((2*HZ)/3)
 211
 212 static void led_work (void *__hub)
 213 {
 214         struct usb_hub          *hub = __hub;
 215         struct usb_device       *hdev = hub->hdev;
 216         unsigned                i;
 217         unsigned                changed = 0;
 218         int                     cursor = -1;
 219
 220         if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
 221                 return;
 222
 223         for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
 224                 unsigned        selector, mode;
 225
 226                 /* 30%-50% duty cycle */
 227
 228                 switch (hub->indicator[i]) {
 229                 /* cycle marker */
 230                 case INDICATOR_CYCLE:
 231                         cursor = i;
 232                         selector = HUB_LED_AUTO;
 233                         mode = INDICATOR_AUTO;
 234                         break;
 235                 /* blinking green = sw attention */
 236                 case INDICATOR_GREEN_BLINK:
 237                         selector = HUB_LED_GREEN;
 238                         mode = INDICATOR_GREEN_BLINK_OFF;
 239                         break;
 240                 case INDICATOR_GREEN_BLINK_OFF:
 241                         selector = HUB_LED_OFF;
 242                         mode = INDICATOR_GREEN_BLINK;
 243                         break;
 244                 /* blinking amber = hw attention */
 245                 case INDICATOR_AMBER_BLINK:
 246                         selector = HUB_LED_AMBER;
 247                         mode = INDICATOR_AMBER_BLINK_OFF;
 248                         break;
 249                 case INDICATOR_AMBER_BLINK_OFF:
 250                         selector = HUB_LED_OFF;
 251                         mode = INDICATOR_AMBER_BLINK;
 252                         break;
 253                 /* blink green/amber = reserved */
 254                 case INDICATOR_ALT_BLINK:
 255                         selector = HUB_LED_GREEN;
 256                         mode = INDICATOR_ALT_BLINK_OFF;
 257                         break;
 258                 case INDICATOR_ALT_BLINK_OFF:
 259                         selector = HUB_LED_AMBER;
 260                         mode = INDICATOR_ALT_BLINK;
 261                         break;
 262                 default:
 263                         continue;
 264                 }
 265                 if (selector != HUB_LED_AUTO)
 266                         changed = 1;
 267                 set_port_led(hub, i + 1, selector);
 268                 hub->indicator[i] = mode;
 269         }
 270         if (!changed && blinkenlights) {
 271                 cursor++;
 272                 cursor %= hub->descriptor->bNbrPorts;
 273                 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
 274                 hub->indicator[cursor] = INDICATOR_CYCLE;
 275                 changed++;
 276         }
 277         if (changed)
 278                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 279 }
 280
 281 /* use a short timeout for hub/port status fetches */
 282 #define USB_STS_TIMEOUT         1000
 283 #define USB_STS_RETRIES         5
 284
 285 /*
 286  * USB 2.0 spec Section 11.24.2.6
 287  */
 288 static int get_hub_status(struct usb_device *hdev,
 289                 struct usb_hub_status *data)
 290 {
 291         int i, status = -ETIMEDOUT;
 292
 293         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
 294                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 295                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
 296                         data, sizeof(*data), USB_STS_TIMEOUT);
 297         }
 298         return status;
 299 }
 300
 301 /*
 302  * USB 2.0 spec Section 11.24.2.7
 303  */
 304 static int get_port_status(struct usb_device *hdev, int port1,
 305                 struct usb_port_status *data)
 306 {
 307         int i, status = -ETIMEDOUT;
 308
 309         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
 310                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 311                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
 312                         data, sizeof(*data), USB_STS_TIMEOUT);
 313         }
 314         return status;
 315 }
 316
 317 static void kick_khubd(struct usb_hub *hub)
 318 {
 319         unsigned long   flags;
 320
 321         spin_lock_irqsave(&hub_event_lock, flags);
 322         if (list_empty(&hub->event_list)) {
 323                 list_add_tail(&hub->event_list, &hub_event_list);
 324                 wake_up(&khubd_wait);
 325         }
 326         spin_unlock_irqrestore(&hub_event_lock, flags);
 327 }
 328
 329 void usb_kick_khubd(struct usb_device *hdev)
 330 {
 331         kick_khubd(hdev_to_hub(hdev));
 332 }
 333
 334
 335 /* completion function, fires on port status changes and various faults */
 336 static void hub_irq(struct urb *urb)
 337 {
 338         struct usb_hub *hub = urb->context;
 339         int status;
 340         int i;
 341         unsigned long bits;
 342
 343         switch (urb->status) {
 344         case -ENOENT:           /* synchronous unlink */
 345         case -ECONNRESET:       /* async unlink */
 346         case -ESHUTDOWN:        /* hardware going away */
 347                 return;
 348
 349         default:                /* presumably an error */
 350                 /* Cause a hub reset after 10 consecutive errors */
 351                 dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
 352                 if ((++hub->nerrors < 10) || hub->error)
 353                         goto resubmit;
 354                 hub->error = urb->status;
 355                 /* FALL THROUGH */
 356
 357         /* let khubd handle things */
 358         case 0:                 /* we got data:  port status changed */
 359                 bits = 0;
 360                 for (i = 0; i < urb->actual_length; ++i)
 361                         bits |= ((unsigned long) ((*hub->buffer)[i]))
 362                                         << (i*8);
 363                 hub->event_bits[0] = bits;
 364                 break;
 365         }
 366
 367         hub->nerrors = 0;
 368
 369         /* Something happened, let khubd figure it out */
 370         kick_khubd(hub);
 371
 372 resubmit:
 373         if (hub->quiescing)
 374                 return;
 375
 376         if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
 377                         && status != -ENODEV && status != -EPERM)
 378                 dev_err (hub->intfdev, "resubmit --> %d\n", status);
 379 }
 380
 381 /* USB 2.0 spec Section 11.24.2.3 */
 382 static inline int
 383 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
 384 {
 385         return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 386                                HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
 387                                tt, NULL, 0, 1000);
 388 }
 389
 390 /*
 391  * enumeration blocks khubd for a long time. we use keventd instead, since
 392  * long blocking there is the exception, not the rule.  accordingly, HCDs
 393  * talking to TTs must queue control transfers (not just bulk and iso), so
 394  * both can talk to the same hub concurrently.
 395  */
 396 static void hub_tt_kevent (void *arg)
 397 {
 398         struct usb_hub          *hub = arg;
 399         unsigned long           flags;
 400
 401         spin_lock_irqsave (&hub->tt.lock, flags);
 402         while (!list_empty (&hub->tt.clear_list)) {
 403                 struct list_head        *temp;
 404                 struct usb_tt_clear     *clear;
 405                 struct usb_device       *hdev = hub->hdev;
 406                 int                     status;
 407
 408                 temp = hub->tt.clear_list.next;
 409                 clear = list_entry (temp, struct usb_tt_clear, clear_list);
 410                 list_del (&clear->clear_list);
 411
 412                 /* drop lock so HCD can concurrently report other TT errors */
 413                 spin_unlock_irqrestore (&hub->tt.lock, flags);
 414                 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
 415                 spin_lock_irqsave (&hub->tt.lock, flags);
 416
 417                 if (status)
 418                         dev_err (&hdev->dev,
 419                                 "clear tt %d (%04x) error %d\n",
 420                                 clear->tt, clear->devinfo, status);
 421                 kfree(clear);
 422         }
 423         spin_unlock_irqrestore (&hub->tt.lock, flags);
 424 }
 425
 426 /**
 427  * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
 428  * @udev: the device whose split transaction failed
 429  * @pipe: identifies the endpoint of the failed transaction
 430  *
 431  * High speed HCDs use this to tell the hub driver that some split control or
 432  * bulk transaction failed in a way that requires clearing internal state of
 433  * a transaction translator.  This is normally detected (and reported) from
 434  * interrupt context.
 435  *
 436  * It may not be possible for that hub to handle additional full (or low)
 437  * speed transactions until that state is fully cleared out.
 438  */
 439 void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
 440 {
 441         struct usb_tt           *tt = udev->tt;
 442         unsigned long           flags;
 443         struct usb_tt_clear     *clear;
 444
 445         /* we've got to cope with an arbitrary number of pending TT clears,
 446          * since each TT has "at least two" buffers that can need it (and
 447          * there can be many TTs per hub).  even if they're uncommon.
 448          */
 449         if ((clear = kmalloc (sizeof *clear, SLAB_ATOMIC)) == NULL) {
 450                 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
 451                 /* FIXME recover somehow ... RESET_TT? */
 452                 return;
 453         }
 454
 455         /* info that CLEAR_TT_BUFFER needs */
 456         clear->tt = tt->multi ? udev->ttport : 1;
 457         clear->devinfo = usb_pipeendpoint (pipe);
 458         clear->devinfo |= udev->devnum << 4;
 459         clear->devinfo |= usb_pipecontrol (pipe)
 460                         ? (USB_ENDPOINT_XFER_CONTROL << 11)
 461                         : (USB_ENDPOINT_XFER_BULK << 11);
 462         if (usb_pipein (pipe))
 463                 clear->devinfo |= 1 << 15;
 464
 465         /* tell keventd to clear state for this TT */
 466         spin_lock_irqsave (&tt->lock, flags);
 467         list_add_tail (&clear->clear_list, &tt->clear_list);
 468         schedule_work (&tt->kevent);
 469         spin_unlock_irqrestore (&tt->lock, flags);
 470 }
 471
 472 static void hub_power_on(struct usb_hub *hub)
 473 {
 474         int port1;
 475         unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
 476         u16 wHubCharacteristics =
 477                         le16_to_cpu(hub->descriptor->wHubCharacteristics);
 478
 479         /* Enable power on each port.  Some hubs have reserved values
 480          * of LPSM (> 2) in their descriptors, even though they are
 481          * USB 2.0 hubs.  Some hubs do not implement port-power switching
 482          * but only emulate it.  In all cases, the ports won't work
 483          * unless we send these messages to the hub.
 484          */
 485         if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
 486                 dev_dbg(hub->intfdev, "enabling power on all ports\n");
 487         else
 488                 dev_dbg(hub->intfdev, "trying to enable port power on "
 489                                 "non-switchable hub\n");
 490         for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
 491                 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
 492
 493         /* Wait at least 100 msec for power to become stable */
 494         msleep(max(pgood_delay, (unsigned) 100));
 495 }
 496
 497 static void hub_quiesce(struct usb_hub *hub)
 498 {
 499         /* (nonblocking) khubd and related activity won't re-trigger */
 500         hub->quiescing = 1;
 501         hub->activating = 0;
 502         hub->resume_root_hub = 0;
 503
 504         /* (blocking) stop khubd and related activity */
 505         usb_kill_urb(hub->urb);
 506         if (hub->has_indicators)
 507                 cancel_delayed_work(&hub->leds);
 508         if (hub->has_indicators || hub->tt.hub)
 509                 flush_scheduled_work();
 510 }
 511
 512 static void hub_activate(struct usb_hub *hub)
 513 {
 514         int     status;
 515
 516         hub->quiescing = 0;
 517         hub->activating = 1;
 518         hub->resume_root_hub = 0;
 519         status = usb_submit_urb(hub->urb, GFP_NOIO);
 520         if (status < 0)
 521                 dev_err(hub->intfdev, "activate --> %d\n", status);
 522         if (hub->has_indicators && blinkenlights)
 523                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 524
 525         /* scan all ports ASAP */
 526         kick_khubd(hub);
 527 }
 528
 529 static int hub_hub_status(struct usb_hub *hub,
 530                 u16 *status, u16 *change)
 531 {
 532         int ret;
 533
 534         ret = get_hub_status(hub->hdev, &hub->status->hub);
 535         if (ret < 0)
 536                 dev_err (hub->intfdev,
 537                         "%s failed (err = %d)\n", __FUNCTION__, ret);
 538         else {
 539                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
 540                 *change = le16_to_cpu(hub->status->hub.wHubChange);
 541                 ret = 0;
 542         }
 543         return ret;
 544 }
 545
 546 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
 547 {
 548         struct usb_device *hdev = hub->hdev;
 549         int ret;
 550
 551         if (hdev->children[port1-1] && set_state) {
 552                 usb_set_device_state(hdev->children[port1-1],
 553                                 USB_STATE_NOTATTACHED);
 554         }
 555         ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
 556         if (ret)
 557                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
 558                         port1, ret);
 559
 560         return ret;
 561 }
 562
 563
 564 /* caller has locked the hub device */
 565 static void hub_pre_reset(struct usb_interface *intf)
 566 {
 567         struct usb_hub *hub = usb_get_intfdata(intf);
 568         struct usb_device *hdev = hub->hdev;
 569         int port1;
 570
 571         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
 572                 if (hdev->children[port1 - 1]) {
 573                         usb_disconnect(&hdev->children[port1 - 1]);
 574                         if (hub->error == 0)
 575                                 hub_port_disable(hub, port1, 0);
 576                 }
 577         }
 578         hub_quiesce(hub);
 579 }
 580
 581 /* caller has locked the hub device */
 582 static void hub_post_reset(struct usb_interface *intf)
 583 {
 584         struct usb_hub *hub = usb_get_intfdata(intf);
 585
 586         hub_activate(hub);
 587         hub_power_on(hub);
 588 }
 589
 590
 591 static int hub_configure(struct usb_hub *hub,
 592         struct usb_endpoint_descriptor *endpoint)
 593 {
 594         struct usb_device *hdev = hub->hdev;
 595         struct device *hub_dev = hub->intfdev;
 596         u16 hubstatus, hubchange;
 597         u16 wHubCharacteristics;
 598         unsigned int pipe;
 599         int maxp, ret;
 600         char *message;
 601
 602         hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
 603                         &hub->buffer_dma);
 604         if (!hub->buffer) {
 605                 message = "can't allocate hub irq buffer";
 606                 ret = -ENOMEM;
 607                 goto fail;
 608         }
 609
 610         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
 611         if (!hub->status) {
 612                 message = "can't kmalloc hub status buffer";
 613                 ret = -ENOMEM;
 614                 goto fail;
 615         }
 616
 617         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
 618         if (!hub->descriptor) {
 619                 message = "can't kmalloc hub descriptor";
 620                 ret = -ENOMEM;
 621                 goto fail;
 622         }
 623
 624         /* Request the entire hub descriptor.
 625          * hub->descriptor can handle USB_MAXCHILDREN ports,
 626          * but the hub can/will return fewer bytes here.
 627          */
 628         ret = get_hub_descriptor(hdev, hub->descriptor,
 629                         sizeof(*hub->descriptor));
 630         if (ret < 0) {
 631                 message = "can't read hub descriptor";
 632                 goto fail;
 633         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
 634                 message = "hub has too many ports!";
 635                 ret = -ENODEV;
 636                 goto fail;
 637         }
 638
 639         hdev->maxchild = hub->descriptor->bNbrPorts;
 640         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
 641                 (hdev->maxchild == 1) ? "" : "s");
 642
 643         wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
 644
 645         if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
 646                 int     i;
 647                 char    portstr [USB_MAXCHILDREN + 1];
 648
 649                 for (i = 0; i < hdev->maxchild; i++)
 650                         portstr[i] = hub->descriptor->DeviceRemovable
 651                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
 652                                 ? 'F' : 'R';
 653                 portstr[hdev->maxchild] = 0;
 654                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
 655         } else
 656                 dev_dbg(hub_dev, "standalone hub\n");
 657
 658         switch (wHubCharacteristics & HUB_CHAR_LPSM) {
 659                 case 0x00:
 660                         dev_dbg(hub_dev, "ganged power switching\n");
 661                         break;
 662                 case 0x01:
 663                         dev_dbg(hub_dev, "individual port power switching\n");
 664                         break;
 665                 case 0x02:
 666                 case 0x03:
 667                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
 668                         break;
 669         }
 670
 671         switch (wHubCharacteristics & HUB_CHAR_OCPM) {
 672                 case 0x00:
 673                         dev_dbg(hub_dev, "global over-current protection\n");
 674                         break;
 675                 case 0x08:
 676                         dev_dbg(hub_dev, "individual port over-current protection\n");
 677                         break;
 678                 case 0x10:
 679                 case 0x18:
 680                         dev_dbg(hub_dev, "no over-current protection\n");
 681                         break;
 682         }
 683
 684         spin_lock_init (&hub->tt.lock);
 685         INIT_LIST_HEAD (&hub->tt.clear_list);
 686         INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub);
 687         switch (hdev->descriptor.bDeviceProtocol) {
 688                 case 0:
 689                         break;
 690                 case 1:
 691                         dev_dbg(hub_dev, "Single TT\n");
 692                         hub->tt.hub = hdev;
 693                         break;
 694                 case 2:
 695                         ret = usb_set_interface(hdev, 0, 1);
 696                         if (ret == 0) {
 697                                 dev_dbg(hub_dev, "TT per port\n");
 698                                 hub->tt.multi = 1;
 699                         } else
 700                                 dev_err(hub_dev, "Using single TT (err %d)\n",
 701                                         ret);
 702                         hub->tt.hub = hdev;
 703                         break;
 704                 default:
 705                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
 706                                 hdev->descriptor.bDeviceProtocol);
 707                         break;
 708         }
 709
 710         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
 711         switch (wHubCharacteristics & HUB_CHAR_TTTT) {
 712                 case HUB_TTTT_8_BITS:
 713                         if (hdev->descriptor.bDeviceProtocol != 0) {
 714                                 hub->tt.think_time = 666;
 715                                 dev_dbg(hub_dev, "TT requires at most %d "
 716                                                 "FS bit times (%d ns)\n",
 717                                         8, hub->tt.think_time);
 718                         }
 719                         break;
 720                 case HUB_TTTT_16_BITS:
 721                         hub->tt.think_time = 666 * 2;
 722                         dev_dbg(hub_dev, "TT requires at most %d "
 723                                         "FS bit times (%d ns)\n",
 724                                 16, hub->tt.think_time);
 725                         break;
 726                 case HUB_TTTT_24_BITS:
 727                         hub->tt.think_time = 666 * 3;
 728                         dev_dbg(hub_dev, "TT requires at most %d "
 729                                         "FS bit times (%d ns)\n",
 730                                 24, hub->tt.think_time);
 731                         break;
 732                 case HUB_TTTT_32_BITS:
 733                         hub->tt.think_time = 666 * 4;
 734                         dev_dbg(hub_dev, "TT requires at most %d "
 735                                         "FS bit times (%d ns)\n",
 736                                 32, hub->tt.think_time);
 737                         break;
 738         }
 739
 740         /* probe() zeroes hub->indicator[] */
 741         if (wHubCharacteristics & HUB_CHAR_PORTIND) {
 742                 hub->has_indicators = 1;
 743                 dev_dbg(hub_dev, "Port indicators are supported\n");
 744         }
 745
 746         dev_dbg(hub_dev, "power on to power good time: %dms\n",
 747                 hub->descriptor->bPwrOn2PwrGood * 2);
 748
 749         /* power budgeting mostly matters with bus-powered hubs,
 750          * and battery-powered root hubs (may provide just 8 mA).
 751          */
 752         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
 753         if (ret < 2) {
 754                 message = "can't get hub status";
 755                 goto fail;
 756         }
 757         le16_to_cpus(&hubstatus);
 758         if (hdev == hdev->bus->root_hub) {
 759                 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
 760                         hub->mA_per_port = 500;
 761                 else {
 762                         hub->mA_per_port = hdev->bus_mA;
 763                         hub->limited_power = 1;
 764                 }
 765         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
 766                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
 767                         hub->descriptor->bHubContrCurrent);
 768                 hub->limited_power = 1;
 769                 if (hdev->maxchild > 0) {
 770                         int remaining = hdev->bus_mA -
 771                                         hub->descriptor->bHubContrCurrent;
 772
 773                         if (remaining < hdev->maxchild * 100)
 774                                 dev_warn(hub_dev,
 775                                         "insufficient power available "
 776                                         "to use all downstream ports\n");
 777                         hub->mA_per_port = 100;         /* 7.2.1.1 */
 778                 }
 779         } else {        /* Self-powered external hub */
 780                 /* FIXME: What about battery-powered external hubs that
 781                  * provide less current per port? */
 782                 hub->mA_per_port = 500;
 783         }
 784         if (hub->mA_per_port < 500)
 785                 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
 786                                 hub->mA_per_port);
 787
 788         ret = hub_hub_status(hub, &hubstatus, &hubchange);
 789         if (ret < 0) {
 790                 message = "can't get hub status";
 791                 goto fail;
 792         }
 793
 794         /* local power status reports aren't always correct */
 795         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
 796                 dev_dbg(hub_dev, "local power source is %s\n",
 797                         (hubstatus & HUB_STATUS_LOCAL_POWER)
 798                         ? "lost (inactive)" : "good");
 799
 800         if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
 801                 dev_dbg(hub_dev, "%sover-current condition exists\n",
 802                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
 803
 804         /* set up the interrupt endpoint
 805          * We use the EP's maxpacket size instead of (PORTS+1+7)/8
 806          * bytes as USB2.0[11.12.3] says because some hubs are known
 807          * to send more data (and thus cause overflow). For root hubs,
 808          * maxpktsize is defined in hcd.c's fake endpoint descriptors
 809          * to be big enough for at least USB_MAXCHILDREN ports. */
 810         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
 811         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
 812
 813         if (maxp > sizeof(*hub->buffer))
 814                 maxp = sizeof(*hub->buffer);
 815
 816         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
 817         if (!hub->urb) {
 818                 message = "couldn't allocate interrupt urb";
 819                 ret = -ENOMEM;
 820                 goto fail;
 821         }
 822
 823         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
 824                 hub, endpoint->bInterval);
 825         hub->urb->transfer_dma = hub->buffer_dma;
 826         hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 827
 828         /* maybe cycle the hub leds */
 829         if (hub->has_indicators && blinkenlights)
 830                 hub->indicator [0] = INDICATOR_CYCLE;
 831
 832         hub_power_on(hub);
 833         hub_activate(hub);
 834         return 0;
 835
 836 fail:
 837         dev_err (hub_dev, "config failed, %s (err %d)\n",
 838                         message, ret);
 839         /* hub_disconnect() frees urb and descriptor */
 840         return ret;
 841 }
 842
 843 static unsigned highspeed_hubs;
 844
 845 static void hub_disconnect(struct usb_interface *intf)
 846 {
 847         struct usb_hub *hub = usb_get_intfdata (intf);
 848         struct usb_device *hdev;
 849
 850         /* Disconnect all children and quiesce the hub */
 851         hub->error = 0;
 852         hub_pre_reset(intf);
 853
 854         usb_set_intfdata (intf, NULL);
 855         hdev = hub->hdev;
 856
 857         if (hdev->speed == USB_SPEED_HIGH)
 858                 highspeed_hubs--;
 859
 860         usb_free_urb(hub->urb);
 861         hub->urb = NULL;
 862
 863         spin_lock_irq(&hub_event_lock);
 864         list_del_init(&hub->event_list);
 865         spin_unlock_irq(&hub_event_lock);
 866
 867         kfree(hub->descriptor);
 868         hub->descriptor = NULL;
 869
 870         kfree(hub->status);
 871         hub->status = NULL;
 872
 873         if (hub->buffer) {
 874                 usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
 875                                 hub->buffer_dma);
 876                 hub->buffer = NULL;
 877         }
 878
 879         kfree(hub);
 880 }
 881
 882 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
 883 {
 884         struct usb_host_interface *desc;
 885         struct usb_endpoint_descriptor *endpoint;
 886         struct usb_device *hdev;
 887         struct usb_hub *hub;
 888
 889         desc = intf->cur_altsetting;
 890         hdev = interface_to_usbdev(intf);
 891
 892 #ifdef  CONFIG_USB_OTG_BLACKLIST_HUB
 893         if (hdev->parent) {
 894                 dev_warn(&intf->dev, "ignoring external hub\n");
 895                 return -ENODEV;
 896         }
 897 #endif
 898
 899         /* Some hubs have a subclass of 1, which AFAICT according to the */
 900         /*  specs is not defined, but it works */
 901         if ((desc->desc.bInterfaceSubClass != 0) &&
 902             (desc->desc.bInterfaceSubClass != 1)) {
 903 descriptor_error:
 904                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
 905                 return -EIO;
 906         }
 907
 908         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
 909         if (desc->desc.bNumEndpoints != 1)
 910                 goto descriptor_error;
 911
 912         endpoint = &desc->endpoint[0].desc;
 913
 914         /* If it's not an interrupt in endpoint, we'd better punt! */
 915         if (!usb_endpoint_is_int_in(endpoint))
 916                 goto descriptor_error;
 917
 918         /* We found a hub */
 919         dev_info (&intf->dev, "USB hub found\n");
 920
 921         hub = kzalloc(sizeof(*hub), GFP_KERNEL);
 922         if (!hub) {
 923                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
 924                 return -ENOMEM;
 925         }
 926
 927         INIT_LIST_HEAD(&hub->event_list);
 928         hub->intfdev = &intf->dev;
 929         hub->hdev = hdev;
 930         INIT_WORK(&hub->leds, led_work, hub);
 931
 932         usb_set_intfdata (intf, hub);
 933
 934         if (hdev->speed == USB_SPEED_HIGH)
 935                 highspeed_hubs++;
 936
 937         if (hub_configure(hub, endpoint) >= 0)
 938                 return 0;
 939
 940         hub_disconnect (intf);
 941         return -ENODEV;
 942 }
 943
 944 static int
 945 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
 946 {
 947         struct usb_device *hdev = interface_to_usbdev (intf);
 948
 949         /* assert ifno == 0 (part of hub spec) */
 950         switch (code) {
 951         case USBDEVFS_HUB_PORTINFO: {
 952                 struct usbdevfs_hub_portinfo *info = user_data;
 953                 int i;
 954
 955                 spin_lock_irq(&device_state_lock);
 956                 if (hdev->devnum <= 0)
 957                         info->nports = 0;
 958                 else {
 959                         info->nports = hdev->maxchild;
 960                         for (i = 0; i < info->nports; i++) {
 961                                 if (hdev->children[i] == NULL)
 962                                         info->port[i] = 0;
 963                                 else
 964                                         info->port[i] =
 965                                                 hdev->children[i]->devnum;
 966                         }
 967                 }
 968                 spin_unlock_irq(&device_state_lock);
 969
 970                 return info->nports + 1;
 971                 }
 972
 973         default:
 974                 return -ENOSYS;
 975         }
 976 }
 977
 978
 979 /* grab device/port lock, returning index of that port (zero based).
 980  * protects the upstream link used by this device from concurrent
 981  * tree operations like suspend, resume, reset, and disconnect, which
 982  * apply to everything downstream of a given port.
 983  */
 984 static int locktree(struct usb_device *udev)
 985 {
 986         int                     t;
 987         struct usb_device       *hdev;
 988
 989         if (!udev)
 990                 return -ENODEV;
 991
 992         /* root hub is always the first lock in the series */
 993         hdev = udev->parent;
 994         if (!hdev) {
 995                 usb_lock_device(udev);
 996                 return 0;
 997         }
 998
 999         /* on the path from root to us, lock everything from
1000          * top down, dropping parent locks when not needed
1001          */
1002         t = locktree(hdev);
1003         if (t < 0)
1004                 return t;
1005
1006         /* everything is fail-fast once disconnect
1007          * processing starts
1008          */
1009         if (udev->state == USB_STATE_NOTATTACHED) {
1010                 usb_unlock_device(hdev);
1011                 return -ENODEV;
1012         }
1013
1014         /* when everyone grabs locks top->bottom,
1015          * non-overlapping work may be concurrent
1016          */
1017         usb_lock_device(udev);
1018         usb_unlock_device(hdev);
1019         return udev->portnum;
1020 }
1021
1022 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1023 {
1024         int i;
1025
1026         for (i = 0; i < udev->maxchild; ++i) {
1027                 if (udev->children[i])
1028                         recursively_mark_NOTATTACHED(udev->children[i]);
1029         }
1030         udev->state = USB_STATE_NOTATTACHED;
1031 }
1032
1033 /**
1034  * usb_set_device_state - change a device's current state (usbcore, hcds)
1035  * @udev: pointer to device whose state should be changed
1036  * @new_state: new state value to be stored
1037  *
1038  * udev->state is _not_ fully protected by the device lock.  Although
1039  * most transitions are made only while holding the lock, the state can
1040  * can change to USB_STATE_NOTATTACHED at almost any time.  This
1041  * is so that devices can be marked as disconnected as soon as possible,
1042  * without having to wait for any semaphores to be released.  As a result,
1043  * all changes to any device's state must be protected by the
1044  * device_state_lock spinlock.
1045  *
1046  * Once a device has been added to the device tree, all changes to its state
1047  * should be made using this routine.  The state should _not_ be set directly.
1048  *
1049  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1050  * Otherwise udev->state is set to new_state, and if new_state is
1051  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1052  * to USB_STATE_NOTATTACHED.
1053  */
1054 void usb_set_device_state(struct usb_device *udev,
1055                 enum usb_device_state new_state)
1056 {
1057         unsigned long flags;
1058
1059         spin_lock_irqsave(&device_state_lock, flags);
1060         if (udev->state == USB_STATE_NOTATTACHED)
1061                 ;       /* do nothing */
1062         else if (new_state != USB_STATE_NOTATTACHED) {
1063
1064                 /* root hub wakeup capabilities are managed out-of-band
1065                  * and may involve silicon errata ... ignore them here.
1066                  */
1067                 if (udev->parent) {
1068                         if (udev->state == USB_STATE_SUSPENDED
1069                                         || new_state == USB_STATE_SUSPENDED)
1070                                 ;       /* No change to wakeup settings */
1071                         else if (new_state == USB_STATE_CONFIGURED)
1072                                 device_init_wakeup(&udev->dev,
1073                                         (udev->actconfig->desc.bmAttributes
1074                                          & USB_CONFIG_ATT_WAKEUP));
1075                         else
1076                                 device_init_wakeup(&udev->dev, 0);
1077                 }
1078                 udev->state = new_state;
1079         } else
1080                 recursively_mark_NOTATTACHED(udev);
1081         spin_unlock_irqrestore(&device_state_lock, flags);
1082 }
1083
1084
1085 #ifdef  CONFIG_PM
1086
1087 /**
1088  * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
1089  * @rhdev: struct usb_device for the root hub
1090  *
1091  * The USB host controller driver calls this function when its root hub
1092  * is resumed and Vbus power has been interrupted or the controller
1093  * has been reset.  The routine marks all the children of the root hub
1094  * as NOTATTACHED and marks logical connect-change events on their ports.
1095  */
1096 void usb_root_hub_lost_power(struct usb_device *rhdev)
1097 {
1098         struct usb_hub *hub;
1099         int port1;
1100         unsigned long flags;
1101
1102         dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
1103
1104         /* Make sure no potential wakeup events get lost,
1105          * by forcing the root hub to be resumed.
1106          */
1107         rhdev->dev.power.prev_state.event = PM_EVENT_ON;
1108
1109         spin_lock_irqsave(&device_state_lock, flags);
1110         hub = hdev_to_hub(rhdev);
1111         for (port1 = 1; port1 <= rhdev->maxchild; ++port1) {
1112                 if (rhdev->children[port1 - 1]) {
1113                         recursively_mark_NOTATTACHED(
1114                                         rhdev->children[port1 - 1]);
1115                         set_bit(port1, hub->change_bits);
1116                 }
1117         }
1118         spin_unlock_irqrestore(&device_state_lock, flags);
1119 }
1120 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
1121
1122 #endif  /* CONFIG_PM */
1123
1124 static void choose_address(struct usb_device *udev)
1125 {
1126         int             devnum;
1127         struct usb_bus  *bus = udev->bus;
1128
1129         /* If khubd ever becomes multithreaded, this will need a lock */
1130
1131         /* Try to allocate the next devnum beginning at bus->devnum_next. */
1132         devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1133                         bus->devnum_next);
1134         if (devnum >= 128)
1135                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1136
1137         bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1138
1139         if (devnum < 128) {
1140                 set_bit(devnum, bus->devmap.devicemap);
1141                 udev->devnum = devnum;
1142         }
1143 }
1144
1145 static void release_address(struct usb_device *udev)
1146 {
1147         if (udev->devnum > 0) {
1148                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1149                 udev->devnum = -1;
1150         }
1151 }
1152
1153 /**
1154  * usb_disconnect - disconnect a device (usbcore-internal)
1155  * @pdev: pointer to device being disconnected
1156  * Context: !in_interrupt ()
1157  *
1158  * Something got disconnected. Get rid of it and all of its children.
1159  *
1160  * If *pdev is a normal device then the parent hub must already be locked.
1161  * If *pdev is a root hub then this routine will acquire the
1162  * usb_bus_list_lock on behalf of the caller.
1163  *
1164  * Only hub drivers (including virtual root hub drivers for host
1165  * controllers) should ever call this.
1166  *
1167  * This call is synchronous, and may not be used in an interrupt context.
1168  */
1169 void usb_disconnect(struct usb_device **pdev)
1170 {
1171         struct usb_device       *udev = *pdev;
1172         int                     i;
1173
1174         if (!udev) {
1175                 pr_debug ("%s nodev\n", __FUNCTION__);
1176                 return;
1177         }
1178
1179         /* mark the device as inactive, so any further urb submissions for
1180          * this device (and any of its children) will fail immediately.
1181          * this quiesces everyting except pending urbs.
1182          */
1183         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1184         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1185
1186         usb_lock_device(udev);
1187
1188         /* Free up all the children before we remove this device */
1189         for (i = 0; i < USB_MAXCHILDREN; i++) {
1190                 if (udev->children[i])
1191                         usb_disconnect(&udev->children[i]);
1192         }
1193
1194         /* deallocate hcd/hardware state ... nuking all pending urbs and
1195          * cleaning up all state associated with the current configuration
1196          * so that the hardware is now fully quiesced.
1197          */
1198         dev_dbg (&udev->dev, "unregistering device\n");
1199         usb_disable_device(udev, 0);
1200
1201         usb_unlock_device(udev);
1202
1203         /* Unregister the device.  The device driver is responsible
1204          * for removing the device files from usbfs and sysfs and for
1205          * de-configuring the device.
1206          */
1207         device_del(&udev->dev);
1208
1209         /* Free the device number and delete the parent's children[]
1210          * (or root_hub) pointer.
1211          */
1212         release_address(udev);
1213
1214         /* Avoid races with recursively_mark_NOTATTACHED() */
1215         spin_lock_irq(&device_state_lock);
1216         *pdev = NULL;
1217         spin_unlock_irq(&device_state_lock);
1218
1219         put_device(&udev->dev);
1220 }
1221
1222 #ifdef DEBUG
1223 static void show_string(struct usb_device *udev, char *id, char *string)
1224 {
1225         if (!string)
1226                 return;
1227         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1228 }
1229
1230 #else
1231 static inline void show_string(struct usb_device *udev, char *id, char *string)
1232 {}
1233 #endif
1234
1235
1236 #ifdef  CONFIG_USB_OTG
1237 #include "otg_whitelist.h"
1238 static int __usb_port_suspend(struct usb_device *, int port1);
1239 #endif
1240
1241 /**
1242  * usb_new_device - perform initial device setup (usbcore-internal)
1243  * @udev: newly addressed device (in ADDRESS state)
1244  *
1245  * This is called with devices which have been enumerated, but not yet
1246  * configured.  The device descriptor is available, but not descriptors
1247  * for any device configuration.  The caller must have locked either
1248  * the parent hub (if udev is a normal device) or else the
1249  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1250  * udev has already been installed, but udev is not yet visible through
1251  * sysfs or other filesystem code.
1252  *
1253  * Returns 0 for success (device is configured and listed, with its
1254  * interfaces, in sysfs); else a negative errno value.
1255  *
1256  * This call is synchronous, and may not be used in an interrupt context.
1257  *
1258  * Only the hub driver or root-hub registrar should ever call this.
1259  */
1260 int usb_new_device(struct usb_device *udev)
1261 {
1262         int err;
1263
1264         err = usb_get_configuration(udev);
1265         if (err < 0) {
1266                 dev_err(&udev->dev, "can't read configurations, error %d\n",
1267                         err);
1268                 goto fail;
1269         }
1270
1271         /* read the standard strings and cache them if present */
1272         udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1273         udev->manufacturer = usb_cache_string(udev,
1274                         udev->descriptor.iManufacturer);
1275         udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1276
1277         /* Tell the world! */
1278         dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1279                         "SerialNumber=%d\n",
1280                         udev->descriptor.iManufacturer,
1281                         udev->descriptor.iProduct,
1282                         udev->descriptor.iSerialNumber);
1283         show_string(udev, "Product", udev->product);
1284         show_string(udev, "Manufacturer", udev->manufacturer);
1285         show_string(udev, "SerialNumber", udev->serial);
1286
1287 #ifdef  CONFIG_USB_OTG
1288         /*
1289          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1290          * to wake us after we've powered off VBUS; and HNP, switching roles
1291          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1292          */
1293         if (!udev->bus->is_b_host
1294                         && udev->config
1295                         && udev->parent == udev->bus->root_hub) {
1296                 struct usb_otg_descriptor       *desc = 0;
1297                 struct usb_bus                  *bus = udev->bus;
1298
1299                 /* descriptor may appear anywhere in config */
1300                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1301                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1302                                         USB_DT_OTG, (void **) &desc) == 0) {
1303                         if (desc->bmAttributes & USB_OTG_HNP) {
1304                                 unsigned                port1 = udev->portnum;
1305
1306                                 dev_info(&udev->dev,
1307                                         "Dual-Role OTG device on %sHNP port\n",
1308                                         (port1 == bus->otg_port)
1309                                                 ? "" : "non-");
1310
1311                                 /* enable HNP before suspend, it's simpler */
1312                                 if (port1 == bus->otg_port)
1313                                         bus->b_hnp_enable = 1;
1314                                 err = usb_control_msg(udev,
1315                                         usb_sndctrlpipe(udev, 0),
1316                                         USB_REQ_SET_FEATURE, 0,
1317                                         bus->b_hnp_enable
1318                                                 ? USB_DEVICE_B_HNP_ENABLE
1319                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1320                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1321                                 if (err < 0) {
1322                                         /* OTG MESSAGE: report errors here,
1323                                          * customize to match your product.
1324                                          */
1325                                         dev_info(&udev->dev,
1326                                                 "can't set HNP mode; %d\n",
1327                                                 err);
1328                                         bus->b_hnp_enable = 0;
1329                                 }
1330                         }
1331                 }
1332         }
1333
1334         if (!is_targeted(udev)) {
1335
1336                 /* Maybe it can talk to us, though we can't talk to it.
1337                  * (Includes HNP test device.)
1338                  */
1339                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1340                         err = __usb_port_suspend(udev, udev->bus->otg_port);
1341                         if (err < 0)
1342                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1343                 }
1344                 err = -ENODEV;
1345                 goto fail;
1346         }
1347 #endif
1348
1349         /* Register the device.  The device driver is responsible
1350          * for adding the device files to usbfs and sysfs and for
1351          * configuring the device.
1352          */
1353         err = device_add (&udev->dev);
1354         if (err) {
1355                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1356                 goto fail;
1357         }
1358
1359         return 0;
1360
1361 fail:
1362         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1363         return err;
1364 }
1365
1366
1367 static int hub_port_status(struct usb_hub *hub, int port1,
1368                                u16 *status, u16 *change)
1369 {
1370         int ret;
1371
1372         ret = get_port_status(hub->hdev, port1, &hub->status->port);
1373         if (ret < 0)
1374                 dev_err (hub->intfdev,
1375                         "%s failed (err = %d)\n", __FUNCTION__, ret);
1376         else {
1377                 *status = le16_to_cpu(hub->status->port.wPortStatus);
1378                 *change = le16_to_cpu(hub->status->port.wPortChange);
1379                 ret = 0;
1380         }
1381         return ret;
1382 }
1383
1384
1385 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
1386 static unsigned hub_is_wusb(struct usb_hub *hub)
1387 {
1388         struct usb_hcd *hcd;
1389         if (hub->hdev->parent != NULL)  /* not a root hub? */
1390                 return 0;
1391         hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
1392         return hcd->wireless;
1393 }
1394
1395
1396 #define PORT_RESET_TRIES        5
1397 #define SET_ADDRESS_TRIES       2
1398 #define GET_DESCRIPTOR_TRIES    2
1399 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1400 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1401
1402 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1403 #define HUB_SHORT_RESET_TIME    10
1404 #define HUB_LONG_RESET_TIME     200
1405 #define HUB_RESET_TIMEOUT       500
1406
1407 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1408                                 struct usb_device *udev, unsigned int delay)
1409 {
1410         int delay_time, ret;
1411         u16 portstatus;
1412         u16 portchange;
1413
1414         for (delay_time = 0;
1415                         delay_time < HUB_RESET_TIMEOUT;
1416                         delay_time += delay) {
1417                 /* wait to give the device a chance to reset */
1418                 msleep(delay);
1419
1420                 /* read and decode port status */
1421                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1422                 if (ret < 0)
1423                         return ret;
1424
1425                 /* Device went away? */
1426                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1427                         return -ENOTCONN;
1428
1429                 /* bomb out completely if something weird happened */
1430                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1431                         return -EINVAL;
1432
1433                 /* if we`ve finished resetting, then break out of the loop */
1434                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1435                     (portstatus & USB_PORT_STAT_ENABLE)) {
1436                         if (hub_is_wusb(hub))
1437                                 udev->speed = USB_SPEED_VARIABLE;
1438                         else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1439                                 udev->speed = USB_SPEED_HIGH;
1440                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1441                                 udev->speed = USB_SPEED_LOW;
1442                         else
1443                                 udev->speed = USB_SPEED_FULL;
1444                         return 0;
1445                 }
1446
1447                 /* switch to the long delay after two short delay failures */
1448                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1449                         delay = HUB_LONG_RESET_TIME;
1450
1451                 dev_dbg (hub->intfdev,
1452                         "port %d not reset yet, waiting %dms\n",
1453                         port1, delay);
1454         }
1455
1456         return -EBUSY;
1457 }
1458
1459 static int hub_port_reset(struct usb_hub *hub, int port1,
1460                                 struct usb_device *udev, unsigned int delay)
1461 {
1462         int i, status;
1463
1464         /* Reset the port */
1465         for (i = 0; i < PORT_RESET_TRIES; i++) {
1466                 status = set_port_feature(hub->hdev,
1467                                 port1, USB_PORT_FEAT_RESET);
1468                 if (status)
1469                         dev_err(hub->intfdev,
1470                                         "cannot reset port %d (err = %d)\n",
1471                                         port1, status);
1472                 else {
1473                         status = hub_port_wait_reset(hub, port1, udev, delay);
1474                         if (status && status != -ENOTCONN)
1475                                 dev_dbg(hub->intfdev,
1476                                                 "port_wait_reset: err = %d\n",
1477                                                 status);
1478                 }
1479
1480                 /* return on disconnect or reset */
1481                 switch (status) {
1482                 case 0:
1483                         /* TRSTRCY = 10 ms; plus some extra */
1484                         msleep(10 + 40);
1485                         /* FALL THROUGH */
1486                 case -ENOTCONN:
1487                 case -ENODEV:
1488                         clear_port_feature(hub->hdev,
1489                                 port1, USB_PORT_FEAT_C_RESET);
1490                         /* FIXME need disconnect() for NOTATTACHED device */
1491                         usb_set_device_state(udev, status
1492                                         ? USB_STATE_NOTATTACHED
1493                                         : USB_STATE_DEFAULT);
1494                         return status;
1495                 }
1496
1497                 dev_dbg (hub->intfdev,
1498                         "port %d not enabled, trying reset again...\n",
1499                         port1);
1500                 delay = HUB_LONG_RESET_TIME;
1501         }
1502
1503         dev_err (hub->intfdev,
1504                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1505                 port1);
1506
1507         return status;
1508 }
1509
1510 /*
1511  * Disable a port and mark a logical connnect-change event, so that some
1512  * time later khubd will disconnect() any existing usb_device on the port
1513  * and will re-enumerate if there actually is a device attached.
1514  */
1515 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1516 {
1517         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1518         hub_port_disable(hub, port1, 1);
1519
1520         /* FIXME let caller ask to power down the port:
1521          *  - some devices won't enumerate without a VBUS power cycle
1522          *  - SRP saves power that way
1523          *  - ... new call, TBD ...
1524          * That's easy if this hub can switch power per-port, and
1525          * khubd reactivates the port later (timer, SRP, etc).
1526          * Powerdown must be optional, because of reset/DFU.
1527          */
1528
1529         set_bit(port1, hub->change_bits);
1530         kick_khubd(hub);
1531 }
1532
1533 #ifdef  CONFIG_PM
1534
1535 #ifdef  CONFIG_USB_SUSPEND
1536
1537 /*
1538  * Selective port suspend reduces power; most suspended devices draw
1539  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1540  * All devices below the suspended port are also suspended.
1541  *
1542  * Devices leave suspend state when the host wakes them up.  Some devices
1543  * also support "remote wakeup", where the device can activate the USB
1544  * tree above them to deliver data, such as a keypress or packet.  In
1545  * some cases, this wakes the USB host.
1546  */
1547 static int hub_port_suspend(struct usb_hub *hub, int port1,
1548                 struct usb_device *udev)
1549 {
1550         int     status;
1551
1552         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1553
1554         /* enable remote wakeup when appropriate; this lets the device
1555          * wake up the upstream hub (including maybe the root hub).
1556          *
1557          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1558          * we don't explicitly enable it here.
1559          */
1560         if (udev->do_remote_wakeup) {
1561                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1562                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1563                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1564                                 NULL, 0,
1565                                 USB_CTRL_SET_TIMEOUT);
1566                 if (status)
1567                         dev_dbg(&udev->dev,
1568                                 "won't remote wakeup, status %d\n",
1569                                 status);
1570         }
1571
1572         /* see 7.1.7.6 */
1573         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1574         if (status) {
1575                 dev_dbg(hub->intfdev,
1576                         "can't suspend port %d, status %d\n",
1577                         port1, status);
1578                 /* paranoia:  "should not happen" */
1579                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1580                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1581                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1582                                 NULL, 0,
1583                                 USB_CTRL_SET_TIMEOUT);
1584         } else {
1585                 /* device has up to 10 msec to fully suspend */
1586                 dev_dbg(&udev->dev, "usb %ssuspend\n",
1587                                 udev->auto_pm ? "auto-" : "");
1588                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1589                 msleep(10);
1590         }
1591         return status;
1592 }
1593
1594 /*
1595  * Devices on USB hub ports have only one "suspend" state, corresponding
1596  * to ACPI D2, "may cause the device to lose some context".
1597  * State transitions include:
1598  *
1599  *   - suspend, resume ... when the VBUS power link stays live
1600  *   - suspend, disconnect ... VBUS lost
1601  *
1602  * Once VBUS drop breaks the circuit, the port it's using has to go through
1603  * normal re-enumeration procedures, starting with enabling VBUS power.
1604  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1605  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1606  * timer, no SRP, no requests through sysfs.
1607  *
1608  * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1609  * the root hub for their bus goes into global suspend ... so we don't
1610  * (falsely) update the device power state to say it suspended.
1611  */
1612 static int __usb_port_suspend (struct usb_device *udev, int port1)
1613 {
1614         int     status = 0;
1615
1616         /* caller owns the udev device lock */
1617         if (port1 < 0)
1618                 return port1;
1619
1620         /* we change the device's upstream USB link,
1621          * but root hubs have no upstream USB link.
1622          */
1623         if (udev->parent)
1624                 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1625                                 udev);
1626         else {
1627                 dev_dbg(&udev->dev, "usb %ssuspend\n",
1628                                 udev->auto_pm ? "auto-" : "");
1629                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1630         }
1631         return status;
1632 }
1633
1634 /*
1635  * usb_port_suspend - suspend a usb device's upstream port
1636  * @udev: device that's no longer in active use
1637  * Context: must be able to sleep; device not locked; pm locks held
1638  *
1639  * Suspends a USB device that isn't in active use, conserving power.
1640  * Devices may wake out of a suspend, if anything important happens,
1641  * using the remote wakeup mechanism.  They may also be taken out of
1642  * suspend by the host, using usb_port_resume().  It's also routine
1643  * to disconnect devices while they are suspended.
1644  *
1645  * This only affects the USB hardware for a device; its interfaces
1646  * (and, for hubs, child devices) must already have been suspended.
1647  *
1648  * Suspending OTG devices may trigger HNP, if that's been enabled
1649  * between a pair of dual-role devices.  That will change roles, such
1650  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1651  *
1652  * Returns 0 on success, else negative errno.
1653  */
1654 int usb_port_suspend(struct usb_device *udev)
1655 {
1656         return __usb_port_suspend(udev, udev->portnum);
1657 }
1658
1659 /*
1660  * If the USB "suspend" state is in use (rather than "global suspend"),
1661  * many devices will be individually taken out of suspend state using
1662  * special" resume" signaling.  These routines kick in shortly after
1663  * hardware resume signaling is finished, either because of selective
1664  * resume (by host) or remote wakeup (by device) ... now see what changed
1665  * in the tree that's rooted at this device.
1666  */
1667 static int finish_port_resume(struct usb_device *udev)
1668 {
1669         int     status;
1670         u16     devstatus;
1671
1672         /* caller owns the udev device lock */
1673         dev_dbg(&udev->dev, "finish resume\n");
1674
1675         /* usb ch9 identifies four variants of SUSPENDED, based on what
1676          * state the device resumes to.  Linux currently won't see the
1677          * first two on the host side; they'd be inside hub_port_init()
1678          * during many timeouts, but khubd can't suspend until later.
1679          */
1680         usb_set_device_state(udev, udev->actconfig
1681                         ? USB_STATE_CONFIGURED
1682                         : USB_STATE_ADDRESS);
1683
1684         /* 10.5.4.5 says be sure devices in the tree are still there.
1685          * For now let's assume the device didn't go crazy on resume,
1686          * and device drivers will know about any resume quirks.
1687          */
1688         status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1689         if (status >= 0)
1690                 status = (status == 2 ? 0 : -ENODEV);
1691
1692         if (status)
1693                 dev_dbg(&udev->dev,
1694                         "gone after usb resume? status %d\n",
1695                         status);
1696         else if (udev->actconfig) {
1697                 le16_to_cpus(&devstatus);
1698                 if ((devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
1699                                 && udev->parent) {
1700                         status = usb_control_msg(udev,
1701                                         usb_sndctrlpipe(udev, 0),
1702                                         USB_REQ_CLEAR_FEATURE,
1703                                                 USB_RECIP_DEVICE,
1704                                         USB_DEVICE_REMOTE_WAKEUP, 0,
1705                                         NULL, 0,
1706                                         USB_CTRL_SET_TIMEOUT);
1707                         if (status)
1708                                 dev_dbg(&udev->dev, "disable remote "
1709                                         "wakeup, status %d\n", status);
1710                 }
1711                 status = 0;
1712
1713         } else if (udev->devnum <= 0) {
1714                 dev_dbg(&udev->dev, "bogus resume!\n");
1715                 status = -EINVAL;
1716         }
1717         return status;
1718 }
1719
1720 static int
1721 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1722 {
1723         int     status;
1724
1725         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1726
1727         set_bit(port1, hub->busy_bits);
1728
1729         /* see 7.1.7.7; affects power usage, but not budgeting */
1730         status = clear_port_feature(hub->hdev,
1731                         port1, USB_PORT_FEAT_SUSPEND);
1732         if (status) {
1733                 dev_dbg(hub->intfdev,
1734                         "can't resume port %d, status %d\n",
1735                         port1, status);
1736         } else {
1737                 u16             devstatus;
1738                 u16             portchange;
1739
1740                 /* drive resume for at least 20 msec */
1741                 if (udev)
1742                         dev_dbg(&udev->dev, "usb %sresume\n",
1743                                         udev->auto_pm ? "auto-" : "");
1744                 msleep(25);
1745
1746 #define LIVE_FLAGS      ( USB_PORT_STAT_POWER \
1747                         | USB_PORT_STAT_ENABLE \
1748                         | USB_PORT_STAT_CONNECTION)
1749
1750                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1751                  * stop resume signaling.  Then finish the resume
1752                  * sequence.
1753                  */
1754                 devstatus = portchange = 0;
1755                 status = hub_port_status(hub, port1,
1756                                 &devstatus, &portchange);
1757                 if (status < 0
1758                                 || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
1759                                 || (devstatus & USB_PORT_STAT_SUSPEND) != 0
1760                                 ) {
1761                         dev_dbg(hub->intfdev,
1762                                 "port %d status %04x.%04x after resume, %d\n",
1763                                 port1, portchange, devstatus, status);
1764                         if (status >= 0)
1765                                 status = -ENODEV;
1766                 } else {
1767                         if (portchange & USB_PORT_STAT_C_SUSPEND)
1768                                 clear_port_feature(hub->hdev, port1,
1769                                                 USB_PORT_FEAT_C_SUSPEND);
1770                         /* TRSMRCY = 10 msec */
1771                         msleep(10);
1772                         if (udev)
1773                                 status = finish_port_resume(udev);
1774                 }
1775         }
1776         if (status < 0)
1777                 hub_port_logical_disconnect(hub, port1);
1778
1779         clear_bit(port1, hub->busy_bits);
1780         if (!hub->hdev->parent && !hub->busy_bits[0])
1781                 usb_enable_root_hub_irq(hub->hdev->bus);
1782
1783         return status;
1784 }
1785
1786 /*
1787  * usb_port_resume - re-activate a suspended usb device's upstream port
1788  * @udev: device to re-activate
1789  * Context: must be able to sleep; device not locked; pm locks held
1790  *
1791  * This will re-activate the suspended device, increasing power usage
1792  * while letting drivers communicate again with its endpoints.
1793  * USB resume explicitly guarantees that the power session between
1794  * the host and the device is the same as it was when the device
1795  * suspended.
1796  *
1797  * Returns 0 on success, else negative errno.
1798  */
1799 int usb_port_resume(struct usb_device *udev)
1800 {
1801         int     status;
1802
1803         /* we change the device's upstream USB link,
1804          * but root hubs have no upstream USB link.
1805          */
1806         if (udev->parent) {
1807                 // NOTE this fails if parent is also suspended...
1808                 status = hub_port_resume(hdev_to_hub(udev->parent),
1809                                 udev->portnum, udev);
1810         } else {
1811                 dev_dbg(&udev->dev, "usb %sresume\n",
1812                                 udev->auto_pm ? "auto-" : "");
1813                 status = finish_port_resume(udev);
1814         }
1815         if (status < 0)
1816                 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
1817         return status;
1818 }
1819
1820 static int remote_wakeup(struct usb_device *udev)
1821 {
1822         int     status = 0;
1823
1824         /* All this just to avoid sending a port-resume message
1825          * to the parent hub! */
1826
1827         usb_lock_device(udev);
1828         usb_pm_lock(udev);
1829         if (udev->state == USB_STATE_SUSPENDED) {
1830                 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
1831                 /* TRSMRCY = 10 msec */
1832                 msleep(10);
1833                 status = finish_port_resume(udev);
1834                 if (status == 0)
1835                         udev->dev.power.power_state.event = PM_EVENT_ON;
1836         }
1837         usb_pm_unlock(udev);
1838
1839         if (status == 0)
1840                 usb_autoresume_device(udev, 0);
1841         usb_unlock_device(udev);
1842         return status;
1843 }
1844
1845 #else   /* CONFIG_USB_SUSPEND */
1846
1847 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
1848
1849 int usb_port_suspend(struct usb_device *udev)
1850 {
1851         return 0;
1852 }
1853
1854 static inline int
1855 finish_port_resume(struct usb_device *udev)
1856 {
1857         return 0;
1858 }
1859
1860 static inline int
1861 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1862 {
1863         return 0;
1864 }
1865
1866 int usb_port_resume(struct usb_device *udev)
1867 {
1868         return 0;
1869 }
1870
1871 static inline int remote_wakeup(struct usb_device *udev)
1872 {
1873         return 0;
1874 }
1875
1876 #endif
1877
1878 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
1879 {
1880         struct usb_hub          *hub = usb_get_intfdata (intf);
1881         struct usb_device       *hdev = hub->hdev;
1882         unsigned                port1;
1883
1884         /* fail if children aren't already suspended */
1885         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1886                 struct usb_device       *udev;
1887
1888                 udev = hdev->children [port1-1];
1889                 if (udev && msg.event == PM_EVENT_SUSPEND &&
1890 #ifdef  CONFIG_USB_SUSPEND
1891                                 udev->state != USB_STATE_SUSPENDED
1892 #else
1893                                 udev->dev.power.power_state.event
1894                                         == PM_EVENT_ON
1895 #endif
1896                                 ) {
1897                         if (!hdev->auto_pm)
1898                                 dev_dbg(&intf->dev, "port %d nyet suspended\n",
1899                                                 port1);
1900                         return -EBUSY;
1901                 }
1902         }
1903
1904         /* "global suspend" of the downstream HC-to-USB interface */
1905         if (!hdev->parent) {
1906                 struct usb_bus  *bus = hdev->bus;
1907                 if (bus) {
1908                         int     status = hcd_bus_suspend (bus);
1909
1910                         if (status != 0) {
1911                                 dev_dbg(&hdev->dev, "'global' suspend %d\n",
1912                                         status);
1913                                 return status;
1914                         }
1915                 } else
1916                         return -EOPNOTSUPP;
1917         }
1918
1919         /* stop khubd and related activity */
1920         hub_quiesce(hub);
1921         return 0;
1922 }
1923
1924 static int hub_resume(struct usb_interface *intf)
1925 {
1926         struct usb_device       *hdev = interface_to_usbdev(intf);
1927         struct usb_hub          *hub = usb_get_intfdata (intf);
1928         int                     status;
1929
1930         /* "global resume" of the downstream HC-to-USB interface */
1931         if (!hdev->parent) {
1932                 struct usb_bus  *bus = hdev->bus;
1933                 if (bus) {
1934                         status = hcd_bus_resume (bus);
1935                         if (status) {
1936                                 dev_dbg(&intf->dev, "'global' resume %d\n",
1937                                         status);
1938                                 return status;
1939                         }
1940                 } else
1941                         return -EOPNOTSUPP;
1942                 if (status == 0) {
1943                         /* TRSMRCY = 10 msec */
1944                         msleep(10);
1945                 }
1946         }
1947
1948         /* tell khubd to look for changes on this hub */
1949         hub_activate(hub);
1950         return 0;
1951 }
1952
1953 #else   /* CONFIG_PM */
1954
1955 static inline int remote_wakeup(struct usb_device *udev)
1956 {
1957         return 0;
1958 }
1959
1960 #define hub_suspend NULL
1961 #define hub_resume NULL
1962 #endif
1963
1964 void usb_resume_root_hub(struct usb_device *hdev)
1965 {
1966         struct usb_hub *hub = hdev_to_hub(hdev);
1967
1968         hub->resume_root_hub = 1;
1969         kick_khubd(hub);
1970 }
1971
1972
1973 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
1974  *
1975  * Between connect detection and reset signaling there must be a delay
1976  * of 100ms at least for debounce and power-settling.  The corresponding
1977  * timer shall restart whenever the downstream port detects a disconnect.
1978  *
1979  * Apparently there are some bluetooth and irda-dongles and a number of
1980  * low-speed devices for which this debounce period may last over a second.
1981  * Not covered by the spec - but easy to deal with.
1982  *
1983  * This implementation uses a 1500ms total debounce timeout; if the
1984  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
1985  * every 25ms for transient disconnects.  When the port status has been
1986  * unchanged for 100ms it returns the port status.
1987  */
1988
1989 #define HUB_DEBOUNCE_TIMEOUT    1500
1990 #define HUB_DEBOUNCE_STEP         25
1991 #define HUB_DEBOUNCE_STABLE      100
1992
1993 static int hub_port_debounce(struct usb_hub *hub, int port1)
1994 {
1995         int ret;
1996         int total_time, stable_time = 0;
1997         u16 portchange, portstatus;
1998         unsigned connection = 0xffff;
1999
2000         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2001                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2002                 if (ret < 0)
2003                         return ret;
2004
2005                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2006                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2007                         stable_time += HUB_DEBOUNCE_STEP;
2008                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2009                                 break;
2010                 } else {
2011                         stable_time = 0;
2012                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2013                 }
2014
2015                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2016                         clear_port_feature(hub->hdev, port1,
2017                                         USB_PORT_FEAT_C_CONNECTION);
2018                 }
2019
2020                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2021                         break;
2022                 msleep(HUB_DEBOUNCE_STEP);
2023         }
2024
2025         dev_dbg (hub->intfdev,
2026                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2027                 port1, total_time, stable_time, portstatus);
2028
2029         if (stable_time < HUB_DEBOUNCE_STABLE)
2030                 return -ETIMEDOUT;
2031         return portstatus;
2032 }
2033
2034 static void ep0_reinit(struct usb_device *udev)
2035 {
2036         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2037         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2038         udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2039 }
2040
2041 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2042 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2043
2044 static int hub_set_address(struct usb_device *udev)
2045 {
2046         int retval;
2047
2048         if (udev->devnum == 0)
2049                 return -EINVAL;
2050         if (udev->state == USB_STATE_ADDRESS)
2051                 return 0;
2052         if (udev->state != USB_STATE_DEFAULT)
2053                 return -EINVAL;
2054         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2055                 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2056                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2057         if (retval == 0) {
2058                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2059                 ep0_reinit(udev);
2060         }
2061         return retval;
2062 }
2063
2064 /* Reset device, (re)assign address, get device descriptor.
2065  * Device connection must be stable, no more debouncing needed.
2066  * Returns device in USB_STATE_ADDRESS, except on error.
2067  *
2068  * If this is called for an already-existing device (as part of
2069  * usb_reset_device), the caller must own the device lock.  For a
2070  * newly detected device that is not accessible through any global
2071  * pointers, it's not necessary to lock the device.
2072  */
2073 static int
2074 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2075                 int retry_counter)
2076 {
2077         static DEFINE_MUTEX(usb_address0_mutex);
2078
2079         struct usb_device       *hdev = hub->hdev;
2080         int                     i, j, retval;
2081         unsigned                delay = HUB_SHORT_RESET_TIME;
2082         enum usb_device_speed   oldspeed = udev->speed;
2083         char                    *speed, *type;
2084
2085         /* root hub ports have a slightly longer reset period
2086          * (from USB 2.0 spec, section 7.1.7.5)
2087          */
2088         if (!hdev->parent) {
2089                 delay = HUB_ROOT_RESET_TIME;
2090                 if (port1 == hdev->bus->otg_port)
2091                         hdev->bus->b_hnp_enable = 0;
2092         }
2093
2094         /* Some low speed devices have problems with the quick delay, so */
2095         /*  be a bit pessimistic with those devices. RHbug #23670 */
2096         if (oldspeed == USB_SPEED_LOW)
2097                 delay = HUB_LONG_RESET_TIME;
2098
2099         mutex_lock(&usb_address0_mutex);
2100
2101         /* Reset the device; full speed may morph to high speed */
2102         retval = hub_port_reset(hub, port1, udev, delay);
2103         if (retval < 0)         /* error or disconnect */
2104                 goto fail;
2105                                 /* success, speed is known */
2106         retval = -ENODEV;
2107
2108         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2109                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2110                 goto fail;
2111         }
2112         oldspeed = udev->speed;
2113
2114         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2115          * it's fixed size except for full speed devices.
2116          * For Wireless USB devices, ep0 max packet is always 512 (tho
2117          * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
2118          */
2119         switch (udev->speed) {
2120         case USB_SPEED_VARIABLE:        /* fixed at 512 */
2121                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(512);
2122                 break;
2123         case USB_SPEED_HIGH:            /* fixed at 64 */
2124                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2125                 break;
2126         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2127                 /* to determine the ep0 maxpacket size, try to read
2128                  * the device descriptor to get bMaxPacketSize0 and
2129                  * then correct our initial guess.
2130                  */
2131                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2132                 break;
2133         case USB_SPEED_LOW:             /* fixed at 8 */
2134                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2135                 break;
2136         default:
2137                 goto fail;
2138         }
2139
2140         type = "";
2141         switch (udev->speed) {
2142         case USB_SPEED_LOW:     speed = "low";  break;
2143         case USB_SPEED_FULL:    speed = "full"; break;
2144         case USB_SPEED_HIGH:    speed = "high"; break;
2145         case USB_SPEED_VARIABLE:
2146                                 speed = "variable";
2147                                 type = "Wireless ";
2148                                 break;
2149         default:                speed = "?";    break;
2150         }
2151         dev_info (&udev->dev,
2152                   "%s %s speed %sUSB device using %s and address %d\n",
2153                   (udev->config) ? "reset" : "new", speed, type,
2154                   udev->bus->controller->driver->name, udev->devnum);
2155
2156         /* Set up TT records, if needed  */
2157         if (hdev->tt) {
2158                 udev->tt = hdev->tt;
2159                 udev->ttport = hdev->ttport;
2160         } else if (udev->speed != USB_SPEED_HIGH
2161                         && hdev->speed == USB_SPEED_HIGH) {
2162                 udev->tt = &hub->tt;
2163                 udev->ttport = port1;
2164         }
2165
2166         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2167          * Because device hardware and firmware is sometimes buggy in
2168          * this area, and this is how Linux has done it for ages.
2169          * Change it cautiously.
2170          *
2171          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2172          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2173          * so it may help with some non-standards-compliant devices.
2174          * Otherwise we start with SET_ADDRESS and then try to read the
2175          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2176          * value.
2177          */
2178         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2179                 if (USE_NEW_SCHEME(retry_counter)) {
2180                         struct usb_device_descriptor *buf;
2181                         int r = 0;
2182
2183 #define GET_DESCRIPTOR_BUFSIZE  64
2184                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2185                         if (!buf) {
2186                                 retval = -ENOMEM;
2187                                 continue;
2188                         }
2189
2190                         /* Use a short timeout the first time through,
2191                          * so that recalcitrant full-speed devices with
2192                          * 8- or 16-byte ep0-maxpackets won't slow things
2193                          * down tremendously by NAKing the unexpectedly
2194                          * early status stage.  Also, retry on all errors;
2195                          * some devices are flakey.
2196                          * 255 is for WUSB devices, we actually need to use 512.
2197                          * WUSB1.0[4.8.1].
2198                          */
2199                         for (j = 0; j < 3; ++j) {
2200                                 buf->bMaxPacketSize0 = 0;
2201                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2202                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2203                                         USB_DT_DEVICE << 8, 0,
2204                                         buf, GET_DESCRIPTOR_BUFSIZE,
2205                                         (i ? USB_CTRL_GET_TIMEOUT : 1000));
2206                                 switch (buf->bMaxPacketSize0) {
2207                                 case 8: case 16: case 32: case 64: case 255:
2208                                         if (buf->bDescriptorType ==
2209                                                         USB_DT_DEVICE) {
2210                                                 r = 0;
2211                                                 break;
2212                                         }
2213                                         /* FALL THROUGH */
2214                                 default:
2215                                         if (r == 0)
2216                                                 r = -EPROTO;
2217                                         break;
2218                                 }
2219                                 if (r == 0)
2220                                         break;
2221                         }
2222                         udev->descriptor.bMaxPacketSize0 =
2223                                         buf->bMaxPacketSize0;
2224                         kfree(buf);
2225
2226                         retval = hub_port_reset(hub, port1, udev, delay);
2227                         if (retval < 0)         /* error or disconnect */
2228                                 goto fail;
2229                         if (oldspeed != udev->speed) {
2230                                 dev_dbg(&udev->dev,
2231                                         "device reset changed speed!\n");
2232                                 retval = -ENODEV;
2233                                 goto fail;
2234                         }
2235                         if (r) {
2236                                 dev_err(&udev->dev, "device descriptor "
2237                                                 "read/%s, error %d\n",
2238                                                 "64", r);
2239                                 retval = -EMSGSIZE;
2240                                 continue;
2241                         }
2242 #undef GET_DESCRIPTOR_BUFSIZE
2243                 }
2244
2245                 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2246                         retval = hub_set_address(udev);
2247                         if (retval >= 0)
2248                                 break;
2249                         msleep(200);
2250                 }
2251                 if (retval < 0) {
2252                         dev_err(&udev->dev,
2253                                 "device not accepting address %d, error %d\n",
2254                                 udev->devnum, retval);
2255                         goto fail;
2256                 }
2257
2258                 /* cope with hardware quirkiness:
2259                  *  - let SET_ADDRESS settle, some device hardware wants it
2260                  *  - read ep0 maxpacket even for high and low speed,
2261                  */
2262                 msleep(10);
2263                 if (USE_NEW_SCHEME(retry_counter))
2264                         break;
2265
2266                 retval = usb_get_device_descriptor(udev, 8);
2267                 if (retval < 8) {
2268                         dev_err(&udev->dev, "device descriptor "
2269                                         "read/%s, error %d\n",
2270                                         "8", retval);
2271                         if (retval >= 0)
2272                                 retval = -EMSGSIZE;
2273                 } else {
2274                         retval = 0;
2275                         break;
2276                 }
2277         }
2278         if (retval)
2279                 goto fail;
2280
2281         i = udev->descriptor.bMaxPacketSize0 == 0xff?
2282             512 : udev->descriptor.bMaxPacketSize0;
2283         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2284                 if (udev->speed != USB_SPEED_FULL ||
2285                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2286                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2287                         retval = -EMSGSIZE;
2288                         goto fail;
2289                 }
2290                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2291                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2292                 ep0_reinit(udev);
2293         }
2294
2295         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2296         if (retval < (signed)sizeof(udev->descriptor)) {
2297                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2298                         "all", retval);
2299                 if (retval >= 0)
2300                         retval = -ENOMSG;
2301                 goto fail;
2302         }
2303
2304         retval = 0;
2305
2306 fail:
2307         if (retval)
2308                 hub_port_disable(hub, port1, 0);
2309         mutex_unlock(&usb_address0_mutex);
2310         return retval;
2311 }
2312
2313 static void
2314 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2315 {
2316         struct usb_qualifier_descriptor *qual;
2317         int                             status;
2318
2319         qual = kmalloc (sizeof *qual, SLAB_KERNEL);
2320         if (qual == NULL)
2321                 return;
2322
2323         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2324                         qual, sizeof *qual);
2325         if (status == sizeof *qual) {
2326                 dev_info(&udev->dev, "not running at top speed; "
2327                         "connect to a high speed hub\n");
2328                 /* hub LEDs are probably harder to miss than syslog */
2329                 if (hub->has_indicators) {
2330                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2331                         schedule_work (&hub->leds);
2332                 }
2333         }
2334         kfree(qual);
2335 }
2336
2337 static unsigned
2338 hub_power_remaining (struct usb_hub *hub)
2339 {
2340         struct usb_device *hdev = hub->hdev;
2341         int remaining;
2342         int port1;
2343
2344         if (!hub->limited_power)
2345                 return 0;
2346
2347         remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
2348         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
2349                 struct usb_device       *udev = hdev->children[port1 - 1];
2350                 int                     delta;
2351
2352                 if (!udev)
2353                         continue;
2354
2355                 /* Unconfigured devices may not use more than 100mA,
2356                  * or 8mA for OTG ports */
2357                 if (udev->actconfig)
2358                         delta = udev->actconfig->desc.bMaxPower * 2;
2359                 else if (port1 != udev->bus->otg_port || hdev->parent)
2360                         delta = 100;
2361                 else
2362                         delta = 8;
2363                 if (delta > hub->mA_per_port)
2364                         dev_warn(&udev->dev, "%dmA is over %umA budget "
2365                                         "for port %d!\n",
2366                                         delta, hub->mA_per_port, port1);
2367                 remaining -= delta;
2368         }
2369         if (remaining < 0) {
2370                 dev_warn(hub->intfdev, "%dmA over power budget!\n",
2371                         - remaining);
2372                 remaining = 0;
2373         }
2374         return remaining;
2375 }
2376
2377 /* Handle physical or logical connection change events.
2378  * This routine is called when:
2379  *      a port connection-change occurs;
2380  *      a port enable-change occurs (often caused by EMI);
2381  *      usb_reset_device() encounters changed descriptors (as from
2382  *              a firmware download)
2383  * caller already locked the hub
2384  */
2385 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2386                                         u16 portstatus, u16 portchange)
2387 {
2388         struct usb_device *hdev = hub->hdev;
2389         struct device *hub_dev = hub->intfdev;
2390         u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2391         int status, i;
2392
2393         dev_dbg (hub_dev,
2394                 "port %d, status %04x, change %04x, %s\n",
2395                 port1, portstatus, portchange, portspeed (portstatus));
2396
2397         if (hub->has_indicators) {
2398                 set_port_led(hub, port1, HUB_LED_AUTO);
2399                 hub->indicator[port1-1] = INDICATOR_AUTO;
2400         }
2401
2402         /* Disconnect any existing devices under this port */
2403         if (hdev->children[port1-1])
2404                 usb_disconnect(&hdev->children[port1-1]);
2405         clear_bit(port1, hub->change_bits);
2406
2407 #ifdef  CONFIG_USB_OTG
2408         /* during HNP, don't repeat the debounce */
2409         if (hdev->bus->is_b_host)
2410                 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2411 #endif
2412
2413         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2414                 status = hub_port_debounce(hub, port1);
2415                 if (status < 0) {
2416                         dev_err (hub_dev,
2417                                 "connect-debounce failed, port %d disabled\n",
2418                                 port1);
2419                         goto done;
2420                 }
2421                 portstatus = status;
2422         }
2423
2424         /* Return now if nothing is connected */
2425         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2426
2427                 /* maybe switch power back on (e.g. root hub was reset) */
2428                 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
2429                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2430                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2431
2432                 if (portstatus & USB_PORT_STAT_ENABLE)
2433                         goto done;
2434                 return;
2435         }
2436
2437 #ifdef  CONFIG_USB_SUSPEND
2438         /* If something is connected, but the port is suspended, wake it up. */
2439         if (portstatus & USB_PORT_STAT_SUSPEND) {
2440                 status = hub_port_resume(hub, port1, NULL);
2441                 if (status < 0) {
2442                         dev_dbg(hub_dev,
2443                                 "can't clear suspend on port %d; %d\n",
2444                                 port1, status);
2445                         goto done;
2446                 }
2447         }
2448 #endif
2449
2450         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2451                 struct usb_device *udev;
2452
2453                 /* reallocate for each attempt, since references
2454                  * to the previous one can escape in various ways
2455                  */
2456                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2457                 if (!udev) {
2458                         dev_err (hub_dev,
2459                                 "couldn't allocate port %d usb_device\n",
2460                                 port1);
2461                         goto done;
2462                 }
2463
2464                 usb_set_device_state(udev, USB_STATE_POWERED);
2465                 udev->speed = USB_SPEED_UNKNOWN;
2466                 udev->bus_mA = hub->mA_per_port;
2467                 udev->level = hdev->level + 1;
2468
2469                 /* set the address */
2470                 choose_address(udev);
2471                 if (udev->devnum <= 0) {
2472                         status = -ENOTCONN;     /* Don't retry */
2473                         goto loop;
2474                 }
2475
2476                 /* reset and get descriptor */
2477                 status = hub_port_init(hub, udev, port1, i);
2478                 if (status < 0)
2479                         goto loop;
2480
2481                 /* consecutive bus-powered hubs aren't reliable; they can
2482                  * violate the voltage drop budget.  if the new child has
2483                  * a "powered" LED, users should notice we didn't enable it
2484                  * (without reading syslog), even without per-port LEDs
2485                  * on the parent.
2486                  */
2487                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2488                                 && udev->bus_mA <= 100) {
2489                         u16     devstat;
2490
2491                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2492                                         &devstat);
2493                         if (status < 2) {
2494                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2495                                 goto loop_disable;
2496                         }
2497                         le16_to_cpus(&devstat);
2498                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2499                                 dev_err(&udev->dev,
2500                                         "can't connect bus-powered hub "
2501                                         "to this port\n");
2502                                 if (hub->has_indicators) {
2503                                         hub->indicator[port1-1] =
2504                                                 INDICATOR_AMBER_BLINK;
2505                                         schedule_work (&hub->leds);
2506                                 }
2507                                 status = -ENOTCONN;     /* Don't retry */
2508                                 goto loop_disable;
2509                         }
2510                 }
2511
2512                 /* check for devices running slower than they could */
2513                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2514                                 && udev->speed == USB_SPEED_FULL
2515                                 && highspeed_hubs != 0)
2516                         check_highspeed (hub, udev, port1);
2517
2518                 /* Store the parent's children[] pointer.  At this point
2519                  * udev becomes globally accessible, although presumably
2520                  * no one will look at it until hdev is unlocked.
2521                  */
2522                 status = 0;
2523
2524                 /* We mustn't add new devices if the parent hub has
2525                  * been disconnected; we would race with the
2526                  * recursively_mark_NOTATTACHED() routine.
2527                  */
2528                 spin_lock_irq(&device_state_lock);
2529                 if (hdev->state == USB_STATE_NOTATTACHED)
2530                         status = -ENOTCONN;
2531                 else
2532                         hdev->children[port1-1] = udev;
2533                 spin_unlock_irq(&device_state_lock);
2534
2535                 /* Run it through the hoops (find a driver, etc) */
2536                 if (!status) {
2537                         status = usb_new_device(udev);
2538                         if (status) {
2539                                 spin_lock_irq(&device_state_lock);
2540                                 hdev->children[port1-1] = NULL;
2541                                 spin_unlock_irq(&device_state_lock);
2542                         }
2543                 }
2544
2545                 if (status)
2546                         goto loop_disable;
2547
2548                 status = hub_power_remaining(hub);
2549                 if (status)
2550                         dev_dbg(hub_dev, "%dmA power budget left\n", status);
2551
2552                 return;
2553
2554 loop_disable:
2555                 hub_port_disable(hub, port1, 1);
2556 loop:
2557                 ep0_reinit(udev);
2558                 release_address(udev);
2559                 usb_put_dev(udev);
2560                 if (status == -ENOTCONN)
2561                         break;
2562         }
2563
2564 done:
2565         hub_port_disable(hub, port1, 1);
2566 }
2567
2568 static void hub_events(void)
2569 {
2570         struct list_head *tmp;
2571         struct usb_device *hdev;
2572         struct usb_interface *intf;
2573         struct usb_hub *hub;
2574         struct device *hub_dev;
2575         u16 hubstatus;
2576         u16 hubchange;
2577         u16 portstatus;
2578         u16 portchange;
2579         int i, ret;
2580         int connect_change;
2581
2582         /*
2583          *  We restart the list every time to avoid a deadlock with
2584          * deleting hubs downstream from this one. This should be
2585          * safe since we delete the hub from the event list.
2586          * Not the most efficient, but avoids deadlocks.
2587          */
2588         while (1) {
2589
2590                 /* Grab the first entry at the beginning of the list */
2591                 spin_lock_irq(&hub_event_lock);
2592                 if (list_empty(&hub_event_list)) {
2593                         spin_unlock_irq(&hub_event_lock);
2594                         break;
2595                 }
2596
2597                 tmp = hub_event_list.next;
2598                 list_del_init(tmp);
2599
2600                 hub = list_entry(tmp, struct usb_hub, event_list);
2601                 hdev = hub->hdev;
2602                 intf = to_usb_interface(hub->intfdev);
2603                 hub_dev = &intf->dev;
2604
2605                 i = hub->resume_root_hub;
2606
2607                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x%s\n",
2608                                 hdev->state, hub->descriptor
2609                                         ? hub->descriptor->bNbrPorts
2610                                         : 0,
2611                                 /* NOTE: expects max 15 ports... */
2612                                 (u16) hub->change_bits[0],
2613                                 (u16) hub->event_bits[0],
2614                                 i ? ", resume root" : "");
2615
2616                 usb_get_intf(intf);
2617                 spin_unlock_irq(&hub_event_lock);
2618
2619                 /* Lock the device, then check to see if we were
2620                  * disconnected while waiting for the lock to succeed. */
2621                 if (locktree(hdev) < 0) {
2622                         usb_put_intf(intf);
2623                         continue;
2624                 }
2625                 if (hub != usb_get_intfdata(intf))
2626                         goto loop;
2627
2628                 /* If the hub has died, clean up after it */
2629                 if (hdev->state == USB_STATE_NOTATTACHED) {
2630                         hub->error = -ENODEV;
2631                         hub_pre_reset(intf);
2632                         goto loop;
2633                 }
2634
2635                 /* Is this is a root hub wanting to reactivate the downstream
2636                  * ports?  If so, be sure the interface resumes even if its
2637                  * stub "device" node was never suspended.
2638                  */
2639                 if (i)
2640                         usb_autoresume_device(hdev, 0);
2641
2642                 /* If this is an inactive or suspended hub, do nothing */
2643                 if (hub->quiescing)
2644                         goto loop;
2645
2646                 if (hub->error) {
2647                         dev_dbg (hub_dev, "resetting for error %d\n",
2648                                 hub->error);
2649
2650                         ret = usb_reset_composite_device(hdev, intf);
2651                         if (ret) {
2652                                 dev_dbg (hub_dev,
2653                                         "error resetting hub: %d\n", ret);
2654                                 goto loop;
2655                         }
2656
2657                         hub->nerrors = 0;
2658                         hub->error = 0;
2659                 }
2660
2661                 /* deal with port status changes */
2662                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2663                         if (test_bit(i, hub->busy_bits))
2664                                 continue;
2665                         connect_change = test_bit(i, hub->change_bits);
2666                         if (!test_and_clear_bit(i, hub->event_bits) &&
2667                                         !connect_change && !hub->activating)
2668                                 continue;
2669
2670                         ret = hub_port_status(hub, i,
2671                                         &portstatus, &portchange);
2672                         if (ret < 0)
2673                                 continue;
2674
2675                         if (hub->activating && !hdev->children[i-1] &&
2676                                         (portstatus &
2677                                                 USB_PORT_STAT_CONNECTION))
2678                                 connect_change = 1;
2679
2680                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2681                                 clear_port_feature(hdev, i,
2682                                         USB_PORT_FEAT_C_CONNECTION);
2683                                 connect_change = 1;
2684                         }
2685
2686                         if (portchange & USB_PORT_STAT_C_ENABLE) {
2687                                 if (!connect_change)
2688                                         dev_dbg (hub_dev,
2689                                                 "port %d enable change, "
2690                                                 "status %08x\n",
2691                                                 i, portstatus);
2692                                 clear_port_feature(hdev, i,
2693                                         USB_PORT_FEAT_C_ENABLE);
2694
2695                                 /*
2696                                  * EM interference sometimes causes badly
2697                                  * shielded USB devices to be shutdown by
2698                                  * the hub, this hack enables them again.
2699                                  * Works at least with mouse driver.
2700                                  */
2701                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
2702                                     && !connect_change
2703                                     && hdev->children[i-1]) {
2704                                         dev_err (hub_dev,
2705                                             "port %i "
2706                                             "disabled by hub (EMI?), "
2707                                             "re-enabling...\n",
2708                                                 i);
2709                                         connect_change = 1;
2710                                 }
2711                         }
2712
2713                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2714                                 clear_port_feature(hdev, i,
2715                                         USB_PORT_FEAT_C_SUSPEND);
2716                                 if (hdev->children[i-1]) {
2717                                         ret = remote_wakeup(hdev->
2718                                                         children[i-1]);
2719                                         if (ret < 0)
2720                                                 connect_change = 1;
2721                                 } else {
2722                                         ret = -ENODEV;
2723                                         hub_port_disable(hub, i, 1);
2724                                 }
2725                                 dev_dbg (hub_dev,
2726                                         "resume on port %d, status %d\n",
2727                                         i, ret);
2728                         }
2729
2730                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2731                                 dev_err (hub_dev,
2732                                         "over-current change on port %d\n",
2733                                         i);
2734                                 clear_port_feature(hdev, i,
2735                                         USB_PORT_FEAT_C_OVER_CURRENT);
2736                                 hub_power_on(hub);
2737                         }
2738
2739                         if (portchange & USB_PORT_STAT_C_RESET) {
2740                                 dev_dbg (hub_dev,
2741                                         "reset change on port %d\n",
2742                                         i);
2743                                 clear_port_feature(hdev, i,
2744                                         USB_PORT_FEAT_C_RESET);
2745                         }
2746
2747                         if (connect_change)
2748                                 hub_port_connect_change(hub, i,
2749                                                 portstatus, portchange);
2750                 } /* end for i */
2751
2752                 /* deal with hub status changes */
2753                 if (test_and_clear_bit(0, hub->event_bits) == 0)
2754                         ;       /* do nothing */
2755                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2756                         dev_err (hub_dev, "get_hub_status failed\n");
2757                 else {
2758                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2759                                 dev_dbg (hub_dev, "power change\n");
2760                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2761                                 if (hubstatus & HUB_STATUS_LOCAL_POWER)
2762                                         /* FIXME: Is this always true? */
2763                                         hub->limited_power = 0;
2764                                 else
2765                                         hub->limited_power = 1;
2766                         }
2767                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
2768                                 dev_dbg (hub_dev, "overcurrent change\n");
2769                                 msleep(500);    /* Cool down */
2770                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2771                                 hub_power_on(hub);
2772                         }
2773                 }
2774
2775                 hub->activating = 0;
2776
2777                 /* If this is a root hub, tell the HCD it's okay to
2778                  * re-enable port-change interrupts now. */
2779                 if (!hdev->parent && !hub->busy_bits[0])
2780                         usb_enable_root_hub_irq(hdev->bus);
2781
2782 loop:
2783                 usb_unlock_device(hdev);
2784                 usb_put_intf(intf);
2785
2786         } /* end while (1) */
2787 }
2788
2789 static int hub_thread(void *__unused)
2790 {
2791         do {
2792                 hub_events();
2793                 wait_event_interruptible(khubd_wait,
2794                                 !list_empty(&hub_event_list) ||
2795                                 kthread_should_stop());
2796                 try_to_freeze();
2797         } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2798
2799         pr_debug("%s: khubd exiting\n", usbcore_name);
2800         return 0;
2801 }
2802
2803 static struct usb_device_id hub_id_table [] = {
2804     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2805       .bDeviceClass = USB_CLASS_HUB},
2806     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2807       .bInterfaceClass = USB_CLASS_HUB},
2808     { }                                         /* Terminating entry */
2809 };
2810
2811 MODULE_DEVICE_TABLE (usb, hub_id_table);
2812
2813 static struct usb_driver hub_driver = {
2814         .name =         "hub",
2815         .probe =        hub_probe,
2816         .disconnect =   hub_disconnect,
2817         .suspend =      hub_suspend,
2818         .resume =       hub_resume,
2819         .pre_reset =    hub_pre_reset,
2820         .post_reset =   hub_post_reset,
2821         .ioctl =        hub_ioctl,
2822         .id_table =     hub_id_table,
2823 };
2824
2825 int usb_hub_init(void)
2826 {
2827         if (usb_register(&hub_driver) < 0) {
2828                 printk(KERN_ERR "%s: can't register hub driver\n",
2829                         usbcore_name);
2830                 return -1;
2831         }
2832
2833         khubd_task = kthread_run(hub_thread, NULL, "khubd");
2834         if (!IS_ERR(khubd_task))
2835                 return 0;
2836
2837         /* Fall through if kernel_thread failed */
2838         usb_deregister(&hub_driver);
2839         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2840
2841         return -1;
2842 }
2843
2844 void usb_hub_cleanup(void)
2845 {
2846         kthread_stop(khubd_task);
2847
2848         /*
2849          * Hub resources are freed for us by usb_deregister. It calls
2850          * usb_driver_purge on every device which in turn calls that
2851          * devices disconnect function if it is using this driver.
2852          * The hub_disconnect function takes care of releasing the
2853          * individual hub resources. -greg
2854          */
2855         usb_deregister(&hub_driver);
2856 } /* usb_hub_cleanup() */
2857
2858 static int config_descriptors_changed(struct usb_device *udev)
2859 {
2860         unsigned                        index;
2861         unsigned                        len = 0;
2862         struct usb_config_descriptor    *buf;
2863
2864         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2865                 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2866                         len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2867         }
2868         buf = kmalloc (len, SLAB_KERNEL);
2869         if (buf == NULL) {
2870                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2871                 /* assume the worst */
2872                 return 1;
2873         }
2874         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2875                 int length;
2876                 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2877
2878                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2879                                 old_length);
2880                 if (length < old_length) {
2881                         dev_dbg(&udev->dev, "config index %d, error %d\n",
2882                                         index, length);
2883                         break;
2884                 }
2885                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2886                                 != 0) {
2887                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2888                                 index, buf->bConfigurationValue);
2889                         break;
2890                 }
2891         }
2892         kfree(buf);
2893         return index != udev->descriptor.bNumConfigurations;
2894 }
2895
2896 /**
2897  * usb_reset_device - perform a USB port reset to reinitialize a device
2898  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2899  *
2900  * WARNING - don't use this routine to reset a composite device
2901  * (one with multiple interfaces owned by separate drivers)!
2902  * Use usb_reset_composite_device() instead.
2903  *
2904  * Do a port reset, reassign the device's address, and establish its
2905  * former operating configuration.  If the reset fails, or the device's
2906  * descriptors change from their values before the reset, or the original
2907  * configuration and altsettings cannot be restored, a flag will be set
2908  * telling khubd to pretend the device has been disconnected and then
2909  * re-connected.  All drivers will be unbound, and the device will be
2910  * re-enumerated and probed all over again.
2911  *
2912  * Returns 0 if the reset succeeded, -ENODEV if the device has been
2913  * flagged for logical disconnection, or some other negative error code
2914  * if the reset wasn't even attempted.
2915  *
2916  * The caller must own the device lock.  For example, it's safe to use
2917  * this from a driver probe() routine after downloading new firmware.
2918  * For calls that might not occur during probe(), drivers should lock
2919  * the device using usb_lock_device_for_reset().
2920  */
2921 int usb_reset_device(struct usb_device *udev)
2922 {
2923         struct usb_device               *parent_hdev = udev->parent;
2924         struct usb_hub                  *parent_hub;
2925         struct usb_device_descriptor    descriptor = udev->descriptor;
2926         int                             i, ret = 0;
2927         int                             port1 = udev->portnum;
2928
2929         if (udev->state == USB_STATE_NOTATTACHED ||
2930                         udev->state == USB_STATE_SUSPENDED) {
2931                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2932                                 udev->state);
2933                 return -EINVAL;
2934         }
2935
2936         if (!parent_hdev) {
2937                 /* this requires hcd-specific logic; see OHCI hc_restart() */
2938                 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2939                 return -EISDIR;
2940         }
2941         parent_hub = hdev_to_hub(parent_hdev);
2942
2943         set_bit(port1, parent_hub->busy_bits);
2944         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
2945
2946                 /* ep0 maxpacket size may change; let the HCD know about it.
2947                  * Other endpoints will be handled by re-enumeration. */
2948                 ep0_reinit(udev);
2949                 ret = hub_port_init(parent_hub, udev, port1, i);
2950                 if (ret >= 0)
2951                         break;
2952         }
2953         clear_bit(port1, parent_hub->busy_bits);
2954         if (!parent_hdev->parent && !parent_hub->busy_bits[0])
2955                 usb_enable_root_hub_irq(parent_hdev->bus);
2956
2957         if (ret < 0)
2958                 goto re_enumerate;
2959
2960         /* Device might have changed firmware (DFU or similar) */
2961         if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
2962                         || config_descriptors_changed (udev)) {
2963                 dev_info(&udev->dev, "device firmware changed\n");
2964                 udev->descriptor = descriptor;  /* for disconnect() calls */
2965                 goto re_enumerate;
2966         }
2967
2968         if (!udev->actconfig)
2969                 goto done;
2970
2971         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2972                         USB_REQ_SET_CONFIGURATION, 0,
2973                         udev->actconfig->desc.bConfigurationValue, 0,
2974                         NULL, 0, USB_CTRL_SET_TIMEOUT);
2975         if (ret < 0) {
2976                 dev_err(&udev->dev,
2977                         "can't restore configuration #%d (error=%d)\n",
2978                         udev->actconfig->desc.bConfigurationValue, ret);
2979                 goto re_enumerate;
2980         }
2981         usb_set_device_state(udev, USB_STATE_CONFIGURED);
2982
2983         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
2984                 struct usb_interface *intf = udev->actconfig->interface[i];
2985                 struct usb_interface_descriptor *desc;
2986
2987                 /* set_interface resets host side toggle even
2988                  * for altsetting zero.  the interface may have no driver.
2989                  */
2990                 desc = &intf->cur_altsetting->desc;
2991                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
2992                         desc->bAlternateSetting);
2993                 if (ret < 0) {
2994                         dev_err(&udev->dev, "failed to restore interface %d "
2995                                 "altsetting %d (error=%d)\n",
2996                                 desc->bInterfaceNumber,
2997                                 desc->bAlternateSetting,
2998                                 ret);
2999                         goto re_enumerate;
3000                 }
3001         }
3002
3003 done:
3004         return 0;
3005
3006 re_enumerate:
3007         hub_port_logical_disconnect(parent_hub, port1);
3008         return -ENODEV;
3009 }
3010 EXPORT_SYMBOL(usb_reset_device);
3011
3012 /**
3013  * usb_reset_composite_device - warn interface drivers and perform a USB port reset
3014  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
3015  * @iface: interface bound to the driver making the request (optional)
3016  *
3017  * Warns all drivers bound to registered interfaces (using their pre_reset
3018  * method), performs the port reset, and then lets the drivers know that
3019  * the reset is over (using their post_reset method).
3020  *
3021  * Return value is the same as for usb_reset_device().
3022  *
3023  * The caller must own the device lock.  For example, it's safe to use
3024  * this from a driver probe() routine after downloading new firmware.
3025  * For calls that might not occur during probe(), drivers should lock
3026  * the device using usb_lock_device_for_reset().
3027  *
3028  * The interface locks are acquired during the pre_reset stage and released
3029  * during the post_reset stage.  However if iface is not NULL and is
3030  * currently being probed, we assume that the caller already owns its
3031  * lock.
3032  */
3033 int usb_reset_composite_device(struct usb_device *udev,
3034                 struct usb_interface *iface)
3035 {
3036         int ret;
3037         struct usb_host_config *config = udev->actconfig;
3038
3039         if (udev->state == USB_STATE_NOTATTACHED ||
3040                         udev->state == USB_STATE_SUSPENDED) {
3041                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3042                                 udev->state);
3043                 return -EINVAL;
3044         }
3045
3046         /* Prevent autosuspend during the reset */
3047         usb_autoresume_device(udev, 1);
3048
3049         if (iface && iface->condition != USB_INTERFACE_BINDING)
3050                 iface = NULL;
3051
3052         if (config) {
3053                 int i;
3054                 struct usb_interface *cintf;
3055                 struct usb_driver *drv;
3056
3057                 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
3058                         cintf = config->interface[i];
3059                         if (cintf != iface)
3060                                 down(&cintf->dev.sem);
3061                         if (device_is_registered(&cintf->dev) &&
3062                                         cintf->dev.driver) {
3063                                 drv = to_usb_driver(cintf->dev.driver);
3064                                 if (drv->pre_reset)
3065                                         (drv->pre_reset)(cintf);
3066                         }
3067                 }
3068         }
3069
3070         ret = usb_reset_device(udev);
3071
3072         if (config) {
3073                 int i;
3074                 struct usb_interface *cintf;
3075                 struct usb_driver *drv;
3076
3077                 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
3078                         cintf = config->interface[i];
3079                         if (device_is_registered(&cintf->dev) &&
3080                                         cintf->dev.driver) {
3081                                 drv = to_usb_driver(cintf->dev.driver);
3082                                 if (drv->post_reset)
3083                                         (drv->post_reset)(cintf);
3084                         }
3085                         if (cintf != iface)
3086                                 up(&cintf->dev.sem);
3087                 }
3088         }
3089
3090         usb_autosuspend_device(udev, 1);
3091         return ret;
3092 }
3093 EXPORT_SYMBOL(usb_reset_composite_device);