drivers/usb/core/hub.c

   1 /*
   2  * USB hub driver.
   3  *
   4  * (C) Copyright 1999 Linus Torvalds
   5  * (C) Copyright 1999 Johannes Erdfelt
   6  * (C) Copyright 1999 Gregory P. Smith
   7  * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
   8  *
   9  */
  10
  11 #include <linux/config.h>
  12 #ifdef CONFIG_USB_DEBUG
  13         #define DEBUG
  14 #else
  15         #undef DEBUG
  16 #endif
  17 #include <linux/kernel.h>
  18 #include <linux/errno.h>
  19 #include <linux/module.h>
  20 #include <linux/moduleparam.h>
  21 #include <linux/completion.h>
  22 #include <linux/sched.h>
  23 #include <linux/list.h>
  24 #include <linux/slab.h>
  25 #include <linux/smp_lock.h>
  26 #include <linux/ioctl.h>
  27 #include <linux/usb.h>
  28 #include <linux/usbdevice_fs.h>
  29 #include <linux/suspend.h>
  30
  31 #include <asm/semaphore.h>
  32 #include <asm/uaccess.h>
  33 #include <asm/byteorder.h>
  34
  35 #include "usb.h"
  36 #include "hcd.h"
  37 #include "hub.h"
  38
  39 /* Protect struct usb_device->state and ->children members
  40  * Note: Both are also protected by ->serialize, except that ->state can
  41  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
  42 static spinlock_t device_state_lock = SPIN_LOCK_UNLOCKED;
  43
  44 /* khubd's worklist and its lock */
  45 static spinlock_t hub_event_lock = SPIN_LOCK_UNLOCKED;
  46 static LIST_HEAD(hub_event_list);       /* List of hubs needing servicing */
  47
  48 /* Wakes up khubd */
  49 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
  50
  51 static pid_t khubd_pid = 0;                     /* PID of khubd */
  52 static DECLARE_COMPLETION(khubd_exited);
  53
  54 /* cycle leds on hubs that aren't blinking for attention */
  55 static int blinkenlights = 0;
  56 module_param (blinkenlights, bool, S_IRUGO);
  57 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
  58
  59 /*
  60  * As of 2.6.10 we introduce a new USB device initialization scheme which
  61  * closely resembles the way Windows works.  Hopefully it will be compatible
  62  * with a wider range of devices than the old scheme.  However some previously
  63  * working devices may start giving rise to "device not accepting address"
  64  * errors; if that happens the user can try the old scheme by adjusting the
  65  * following module parameters.
  66  *
  67  * For maximum flexibility there are two boolean parameters to control the
  68  * hub driver's behavior.  On the first initialization attempt, if the
  69  * "old_scheme_first" parameter is set then the old scheme will be used,
  70  * otherwise the new scheme is used.  If that fails and "use_both_schemes"
  71  * is set, then the driver will make another attempt, using the other scheme.
  72  */
  73 static int old_scheme_first = 0;
  74 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
  75 MODULE_PARM_DESC(old_scheme_first,
  76                  "start with the old device initialization scheme");
  77
  78 static int use_both_schemes = 0;
  79 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
  80 MODULE_PARM_DESC(use_both_schemes,
  81                 "try the other device initialization scheme if the "
  82                 "first one fails");
  83
  84
  85 #ifdef  DEBUG
  86 static inline char *portspeed (int portstatus)
  87 {
  88         if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
  89                 return "480 Mb/s";
  90         else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
  91                 return "1.5 Mb/s";
  92         else
  93                 return "12 Mb/s";
  94 }
  95 #endif
  96
  97 /* for dev_info, dev_dbg, etc */
  98 static inline struct device *hubdev (struct usb_device *hdev)
  99 {
 100         return &hdev->actconfig->interface[0]->dev;
 101 }
 102
 103 /* USB 2.0 spec Section 11.24.4.5 */
 104 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
 105 {
 106         int i, ret;
 107
 108         for (i = 0; i < 3; i++) {
 109                 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 110                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
 111                         USB_DT_HUB << 8, 0, data, size,
 112                         HZ * USB_CTRL_GET_TIMEOUT);
 113                 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
 114                         return ret;
 115         }
 116         return -EINVAL;
 117 }
 118
 119 /*
 120  * USB 2.0 spec Section 11.24.2.1
 121  */
 122 static int clear_hub_feature(struct usb_device *hdev, int feature)
 123 {
 124         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 125                 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, HZ);
 126 }
 127
 128 /*
 129  * USB 2.0 spec Section 11.24.2.2
 130  */
 131 static int clear_port_feature(struct usb_device *hdev, int port, int feature)
 132 {
 133         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 134                 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port, NULL, 0, HZ);
 135 }
 136
 137 /*
 138  * USB 2.0 spec Section 11.24.2.13
 139  */
 140 static int set_port_feature(struct usb_device *hdev, int port, int feature)
 141 {
 142         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 143                 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port, NULL, 0, HZ);
 144 }
 145
 146 /*
 147  * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
 148  * for info about using port indicators
 149  */
 150 static void set_port_led(
 151         struct usb_device *hdev,
 152         int port,
 153         int selector
 154 )
 155 {
 156         int status = set_port_feature(hdev, (selector << 8) | port,
 157                         USB_PORT_FEAT_INDICATOR);
 158         if (status < 0)
 159                 dev_dbg (hubdev (hdev),
 160                         "port %d indicator %s status %d\n",
 161                         port,
 162                         ({ char *s; switch (selector) {
 163                         case HUB_LED_AMBER: s = "amber"; break;
 164                         case HUB_LED_GREEN: s = "green"; break;
 165                         case HUB_LED_OFF: s = "off"; break;
 166                         case HUB_LED_AUTO: s = "auto"; break;
 167                         default: s = "??"; break;
 168                         }; s; }),
 169                         status);
 170 }
 171
 172 #define LED_CYCLE_PERIOD        ((2*HZ)/3)
 173
 174 static void led_work (void *__hub)
 175 {
 176         struct usb_hub          *hub = __hub;
 177         struct usb_device       *hdev = hub->hdev;
 178         unsigned                i;
 179         unsigned                changed = 0;
 180         int                     cursor = -1;
 181
 182         if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
 183                 return;
 184
 185         for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
 186                 unsigned        selector, mode;
 187
 188                 /* 30%-50% duty cycle */
 189
 190                 switch (hub->indicator[i]) {
 191                 /* cycle marker */
 192                 case INDICATOR_CYCLE:
 193                         cursor = i;
 194                         selector = HUB_LED_AUTO;
 195                         mode = INDICATOR_AUTO;
 196                         break;
 197                 /* blinking green = sw attention */
 198                 case INDICATOR_GREEN_BLINK:
 199                         selector = HUB_LED_GREEN;
 200                         mode = INDICATOR_GREEN_BLINK_OFF;
 201                         break;
 202                 case INDICATOR_GREEN_BLINK_OFF:
 203                         selector = HUB_LED_OFF;
 204                         mode = INDICATOR_GREEN_BLINK;
 205                         break;
 206                 /* blinking amber = hw attention */
 207                 case INDICATOR_AMBER_BLINK:
 208                         selector = HUB_LED_AMBER;
 209                         mode = INDICATOR_AMBER_BLINK_OFF;
 210                         break;
 211                 case INDICATOR_AMBER_BLINK_OFF:
 212                         selector = HUB_LED_OFF;
 213                         mode = INDICATOR_AMBER_BLINK;
 214                         break;
 215                 /* blink green/amber = reserved */
 216                 case INDICATOR_ALT_BLINK:
 217                         selector = HUB_LED_GREEN;
 218                         mode = INDICATOR_ALT_BLINK_OFF;
 219                         break;
 220                 case INDICATOR_ALT_BLINK_OFF:
 221                         selector = HUB_LED_AMBER;
 222                         mode = INDICATOR_ALT_BLINK;
 223                         break;
 224                 default:
 225                         continue;
 226                 }
 227                 if (selector != HUB_LED_AUTO)
 228                         changed = 1;
 229                 set_port_led(hdev, i + 1, selector);
 230                 hub->indicator[i] = mode;
 231         }
 232         if (!changed && blinkenlights) {
 233                 cursor++;
 234                 cursor %= hub->descriptor->bNbrPorts;
 235                 set_port_led(hdev, cursor + 1, HUB_LED_GREEN);
 236                 hub->indicator[cursor] = INDICATOR_CYCLE;
 237                 changed++;
 238         }
 239         if (changed)
 240                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 241 }
 242
 243 /*
 244  * USB 2.0 spec Section 11.24.2.6
 245  */
 246 static int get_hub_status(struct usb_device *hdev,
 247                 struct usb_hub_status *data)
 248 {
 249         return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 250                 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
 251                 data, sizeof(*data), HZ * USB_CTRL_GET_TIMEOUT);
 252 }
 253
 254 /*
 255  * USB 2.0 spec Section 11.24.2.7
 256  */
 257 static int get_port_status(struct usb_device *hdev, int port,
 258                 struct usb_port_status *data)
 259 {
 260         return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 261                 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port,
 262                 data, sizeof(*data), HZ * USB_CTRL_GET_TIMEOUT);
 263 }
 264
 265 static void kick_khubd(struct usb_hub *hub)
 266 {
 267         unsigned long   flags;
 268
 269         spin_lock_irqsave(&hub_event_lock, flags);
 270         if (list_empty(&hub->event_list)) {
 271                 list_add_tail(&hub->event_list, &hub_event_list);
 272                 wake_up(&khubd_wait);
 273         }
 274         spin_unlock_irqrestore(&hub_event_lock, flags);
 275 }
 276
 277
 278 /* completion function, fires on port status changes and various faults */
 279 static void hub_irq(struct urb *urb, struct pt_regs *regs)
 280 {
 281         struct usb_hub *hub = (struct usb_hub *)urb->context;
 282         int status;
 283         int i;
 284         unsigned long bits;
 285
 286         switch (urb->status) {
 287         case -ENOENT:           /* synchronous unlink */
 288         case -ECONNRESET:       /* async unlink */
 289         case -ESHUTDOWN:        /* hardware going away */
 290                 return;
 291
 292         default:                /* presumably an error */
 293                 /* Cause a hub reset after 10 consecutive errors */
 294                 dev_dbg (&hub->intf->dev, "transfer --> %d\n", urb->status);
 295                 if ((++hub->nerrors < 10) || hub->error)
 296                         goto resubmit;
 297                 hub->error = urb->status;
 298                 /* FALL THROUGH */
 299
 300         /* let khubd handle things */
 301         case 0:                 /* we got data:  port status changed */
 302                 bits = 0;
 303                 for (i = 0; i < urb->actual_length; ++i)
 304                         bits |= ((unsigned long) ((*hub->buffer)[i]))
 305                                         << (i*8);
 306                 hub->event_bits[0] = bits;
 307                 break;
 308         }
 309
 310         hub->nerrors = 0;
 311
 312         /* Something happened, let khubd figure it out */
 313         kick_khubd(hub);
 314
 315 resubmit:
 316         if (hub->quiescing)
 317                 return;
 318
 319         if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
 320                         && status != -ENODEV && status != -EPERM)
 321                 dev_err (&hub->intf->dev, "resubmit --> %d\n", status);
 322 }
 323
 324 /* USB 2.0 spec Section 11.24.2.3 */
 325 static inline int
 326 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
 327 {
 328         return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 329                                HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
 330                                tt, NULL, 0, HZ);
 331 }
 332
 333 /*
 334  * enumeration blocks khubd for a long time. we use keventd instead, since
 335  * long blocking there is the exception, not the rule.  accordingly, HCDs
 336  * talking to TTs must queue control transfers (not just bulk and iso), so
 337  * both can talk to the same hub concurrently.
 338  */
 339 static void hub_tt_kevent (void *arg)
 340 {
 341         struct usb_hub          *hub = arg;
 342         unsigned long           flags;
 343
 344         spin_lock_irqsave (&hub->tt.lock, flags);
 345         while (!list_empty (&hub->tt.clear_list)) {
 346                 struct list_head        *temp;
 347                 struct usb_tt_clear     *clear;
 348                 struct usb_device       *hdev = hub->hdev;
 349                 int                     status;
 350
 351                 temp = hub->tt.clear_list.next;
 352                 clear = list_entry (temp, struct usb_tt_clear, clear_list);
 353                 list_del (&clear->clear_list);
 354
 355                 /* drop lock so HCD can concurrently report other TT errors */
 356                 spin_unlock_irqrestore (&hub->tt.lock, flags);
 357                 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
 358                 spin_lock_irqsave (&hub->tt.lock, flags);
 359
 360                 if (status)
 361                         dev_err (&hdev->dev,
 362                                 "clear tt %d (%04x) error %d\n",
 363                                 clear->tt, clear->devinfo, status);
 364                 kfree (clear);
 365         }
 366         spin_unlock_irqrestore (&hub->tt.lock, flags);
 367 }
 368
 369 /**
 370  * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
 371  * @dev: the device whose split transaction failed
 372  * @pipe: identifies the endpoint of the failed transaction
 373  *
 374  * High speed HCDs use this to tell the hub driver that some split control or
 375  * bulk transaction failed in a way that requires clearing internal state of
 376  * a transaction translator.  This is normally detected (and reported) from
 377  * interrupt context.
 378  *
 379  * It may not be possible for that hub to handle additional full (or low)
 380  * speed transactions until that state is fully cleared out.
 381  */
 382 void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
 383 {
 384         struct usb_tt           *tt = udev->tt;
 385         unsigned long           flags;
 386         struct usb_tt_clear     *clear;
 387
 388         /* we've got to cope with an arbitrary number of pending TT clears,
 389          * since each TT has "at least two" buffers that can need it (and
 390          * there can be many TTs per hub).  even if they're uncommon.
 391          */
 392         if ((clear = kmalloc (sizeof *clear, SLAB_ATOMIC)) == 0) {
 393                 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
 394                 /* FIXME recover somehow ... RESET_TT? */
 395                 return;
 396         }
 397
 398         /* info that CLEAR_TT_BUFFER needs */
 399         clear->tt = tt->multi ? udev->ttport : 1;
 400         clear->devinfo = usb_pipeendpoint (pipe);
 401         clear->devinfo |= udev->devnum << 4;
 402         clear->devinfo |= usb_pipecontrol (pipe)
 403                         ? (USB_ENDPOINT_XFER_CONTROL << 11)
 404                         : (USB_ENDPOINT_XFER_BULK << 11);
 405         if (usb_pipein (pipe))
 406                 clear->devinfo |= 1 << 15;
 407
 408         /* tell keventd to clear state for this TT */
 409         spin_lock_irqsave (&tt->lock, flags);
 410         list_add_tail (&clear->clear_list, &tt->clear_list);
 411         schedule_work (&tt->kevent);
 412         spin_unlock_irqrestore (&tt->lock, flags);
 413 }
 414
 415 static void hub_power_on(struct usb_hub *hub)
 416 {
 417         int i;
 418
 419         /* if hub supports power switching, enable power on each port */
 420         if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_LPSM) < 2) {
 421                 dev_dbg(&hub->intf->dev, "enabling power on all ports\n");
 422                 for (i = 0; i < hub->descriptor->bNbrPorts; i++)
 423                         set_port_feature(hub->hdev, i + 1,
 424                                         USB_PORT_FEAT_POWER);
 425         }
 426
 427         /* Wait for power to be enabled */
 428         msleep(hub->descriptor->bPwrOn2PwrGood * 2);
 429 }
 430
 431 static void hub_quiesce(struct usb_hub *hub)
 432 {
 433         /* stop khubd and related activity */
 434         hub->quiescing = 1;
 435         usb_kill_urb(hub->urb);
 436         if (hub->has_indicators)
 437                 cancel_delayed_work(&hub->leds);
 438         if (hub->has_indicators || hub->tt.hub)
 439                 flush_scheduled_work();
 440 }
 441
 442 static void hub_activate(struct usb_hub *hub)
 443 {
 444         int     status;
 445
 446         hub->quiescing = 0;
 447         status = usb_submit_urb(hub->urb, GFP_NOIO);
 448         if (status < 0)
 449                 dev_err(&hub->intf->dev, "activate --> %d\n", status);
 450         if (hub->has_indicators && blinkenlights)
 451                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 452
 453         /* scan all ports ASAP */
 454         hub->event_bits[0] = ~0;
 455         kick_khubd(hub);
 456 }
 457
 458 static int hub_hub_status(struct usb_hub *hub,
 459                 u16 *status, u16 *change)
 460 {
 461         int ret;
 462
 463         ret = get_hub_status(hub->hdev, &hub->status->hub);
 464         if (ret < 0)
 465                 dev_err (&hub->intf->dev,
 466                         "%s failed (err = %d)\n", __FUNCTION__, ret);
 467         else {
 468                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
 469                 *change = le16_to_cpu(hub->status->hub.wHubChange);
 470                 ret = 0;
 471         }
 472         return ret;
 473 }
 474
 475 static int hub_configure(struct usb_hub *hub,
 476         struct usb_endpoint_descriptor *endpoint)
 477 {
 478         struct usb_device *hdev = hub->hdev;
 479         struct device *hub_dev = &hub->intf->dev;
 480         u16 hubstatus, hubchange;
 481         unsigned int pipe;
 482         int maxp, ret;
 483         char *message;
 484
 485         hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
 486                         &hub->buffer_dma);
 487         if (!hub->buffer) {
 488                 message = "can't allocate hub irq buffer";
 489                 ret = -ENOMEM;
 490                 goto fail;
 491         }
 492
 493         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
 494         if (!hub->status) {
 495                 message = "can't kmalloc hub status buffer";
 496                 ret = -ENOMEM;
 497                 goto fail;
 498         }
 499
 500         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
 501         if (!hub->descriptor) {
 502                 message = "can't kmalloc hub descriptor";
 503                 ret = -ENOMEM;
 504                 goto fail;
 505         }
 506
 507         /* Request the entire hub descriptor.
 508          * hub->descriptor can handle USB_MAXCHILDREN ports,
 509          * but the hub can/will return fewer bytes here.
 510          */
 511         ret = get_hub_descriptor(hdev, hub->descriptor,
 512                         sizeof(*hub->descriptor));
 513         if (ret < 0) {
 514                 message = "can't read hub descriptor";
 515                 goto fail;
 516         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
 517                 message = "hub has too many ports!";
 518                 ret = -ENODEV;
 519                 goto fail;
 520         }
 521
 522         hdev->maxchild = hub->descriptor->bNbrPorts;
 523         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
 524                 (hdev->maxchild == 1) ? "" : "s");
 525
 526         le16_to_cpus(&hub->descriptor->wHubCharacteristics);
 527
 528         if (hub->descriptor->wHubCharacteristics & HUB_CHAR_COMPOUND) {
 529                 int     i;
 530                 char    portstr [USB_MAXCHILDREN + 1];
 531
 532                 for (i = 0; i < hdev->maxchild; i++)
 533                         portstr[i] = hub->descriptor->DeviceRemovable
 534                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
 535                                 ? 'F' : 'R';
 536                 portstr[hdev->maxchild] = 0;
 537                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
 538         } else
 539                 dev_dbg(hub_dev, "standalone hub\n");
 540
 541         switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_LPSM) {
 542                 case 0x00:
 543                         dev_dbg(hub_dev, "ganged power switching\n");
 544                         break;
 545                 case 0x01:
 546                         dev_dbg(hub_dev, "individual port power switching\n");
 547                         break;
 548                 case 0x02:
 549                 case 0x03:
 550                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
 551                         break;
 552         }
 553
 554         switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) {
 555                 case 0x00:
 556                         dev_dbg(hub_dev, "global over-current protection\n");
 557                         break;
 558                 case 0x08:
 559                         dev_dbg(hub_dev, "individual port over-current protection\n");
 560                         break;
 561                 case 0x10:
 562                 case 0x18:
 563                         dev_dbg(hub_dev, "no over-current protection\n");
 564                         break;
 565         }
 566
 567         spin_lock_init (&hub->tt.lock);
 568         INIT_LIST_HEAD (&hub->tt.clear_list);
 569         INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub);
 570         switch (hdev->descriptor.bDeviceProtocol) {
 571                 case 0:
 572                         break;
 573                 case 1:
 574                         dev_dbg(hub_dev, "Single TT\n");
 575                         hub->tt.hub = hdev;
 576                         break;
 577                 case 2:
 578                         ret = usb_set_interface(hdev, 0, 1);
 579                         if (ret == 0) {
 580                                 dev_dbg(hub_dev, "TT per port\n");
 581                                 hub->tt.multi = 1;
 582                         } else
 583                                 dev_err(hub_dev, "Using single TT (err %d)\n",
 584                                         ret);
 585                         hub->tt.hub = hdev;
 586                         break;
 587                 default:
 588                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
 589                                 hdev->descriptor.bDeviceProtocol);
 590                         break;
 591         }
 592
 593         switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_TTTT) {
 594                 case 0x00:
 595                         if (hdev->descriptor.bDeviceProtocol != 0)
 596                                 dev_dbg(hub_dev, "TT requires at most 8 FS bit times\n");
 597                         break;
 598                 case 0x20:
 599                         dev_dbg(hub_dev, "TT requires at most 16 FS bit times\n");
 600                         break;
 601                 case 0x40:
 602                         dev_dbg(hub_dev, "TT requires at most 24 FS bit times\n");
 603                         break;
 604                 case 0x60:
 605                         dev_dbg(hub_dev, "TT requires at most 32 FS bit times\n");
 606                         break;
 607         }
 608
 609         /* probe() zeroes hub->indicator[] */
 610         if (hub->descriptor->wHubCharacteristics & HUB_CHAR_PORTIND) {
 611                 hub->has_indicators = 1;
 612                 dev_dbg(hub_dev, "Port indicators are supported\n");
 613         }
 614
 615         dev_dbg(hub_dev, "power on to power good time: %dms\n",
 616                 hub->descriptor->bPwrOn2PwrGood * 2);
 617
 618         /* power budgeting mostly matters with bus-powered hubs,
 619          * and battery-powered root hubs (may provide just 8 mA).
 620          */
 621         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
 622         if (ret < 0) {
 623                 message = "can't get hub status";
 624                 goto fail;
 625         }
 626         cpu_to_le16s(&hubstatus);
 627         if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
 628                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
 629                         hub->descriptor->bHubContrCurrent);
 630                 hub->power_budget = (501 - hub->descriptor->bHubContrCurrent)
 631                                         / 2;
 632                 dev_dbg(hub_dev, "%dmA bus power budget for children\n",
 633                         hub->power_budget * 2);
 634         }
 635
 636
 637         ret = hub_hub_status(hub, &hubstatus, &hubchange);
 638         if (ret < 0) {
 639                 message = "can't get hub status";
 640                 goto fail;
 641         }
 642
 643         /* local power status reports aren't always correct */
 644         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
 645                 dev_dbg(hub_dev, "local power source is %s\n",
 646                         (hubstatus & HUB_STATUS_LOCAL_POWER)
 647                         ? "lost (inactive)" : "good");
 648
 649         if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) == 0)
 650                 dev_dbg(hub_dev, "%sover-current condition exists\n",
 651                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
 652
 653         /* set up the interrupt endpoint */
 654         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
 655         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
 656
 657         if (maxp > sizeof(*hub->buffer))
 658                 maxp = sizeof(*hub->buffer);
 659
 660         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
 661         if (!hub->urb) {
 662                 message = "couldn't allocate interrupt urb";
 663                 ret = -ENOMEM;
 664                 goto fail;
 665         }
 666
 667         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
 668                 hub, endpoint->bInterval);
 669         hub->urb->transfer_dma = hub->buffer_dma;
 670         hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 671
 672         /* maybe cycle the hub leds */
 673         if (hub->has_indicators && blinkenlights)
 674                 hub->indicator [0] = INDICATOR_CYCLE;
 675
 676         hub_power_on(hub);
 677         hub->change_bits[0] = ~0;
 678         hub_activate(hub);
 679         return 0;
 680
 681 fail:
 682         dev_err (hub_dev, "config failed, %s (err %d)\n",
 683                         message, ret);
 684         /* hub_disconnect() frees urb and descriptor */
 685         return ret;
 686 }
 687
 688 static unsigned highspeed_hubs;
 689
 690 static void hub_disconnect(struct usb_interface *intf)
 691 {
 692         struct usb_hub *hub = usb_get_intfdata (intf);
 693         struct usb_device *hdev;
 694
 695         if (!hub)
 696                 return;
 697         hdev = hub->hdev;
 698
 699         if (hdev->speed == USB_SPEED_HIGH)
 700                 highspeed_hubs--;
 701
 702         usb_set_intfdata (intf, NULL);
 703
 704         hub_quiesce(hub);
 705         usb_free_urb(hub->urb);
 706         hub->urb = NULL;
 707
 708         spin_lock_irq(&hub_event_lock);
 709         list_del_init(&hub->event_list);
 710         spin_unlock_irq(&hub_event_lock);
 711
 712         if (hub->descriptor) {
 713                 kfree(hub->descriptor);
 714                 hub->descriptor = NULL;
 715         }
 716
 717         if (hub->status) {
 718                 kfree(hub->status);
 719                 hub->status = NULL;
 720         }
 721
 722         if (hub->buffer) {
 723                 usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
 724                                 hub->buffer_dma);
 725                 hub->buffer = NULL;
 726         }
 727
 728         /* Free the memory */
 729         kfree(hub);
 730 }
 731
 732 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
 733 {
 734         struct usb_host_interface *desc;
 735         struct usb_endpoint_descriptor *endpoint;
 736         struct usb_device *hdev;
 737         struct usb_hub *hub;
 738         struct device *hub_dev;
 739
 740         desc = intf->cur_altsetting;
 741         hdev = interface_to_usbdev(intf);
 742         hub_dev = &intf->dev;
 743
 744         /* Some hubs have a subclass of 1, which AFAICT according to the */
 745         /*  specs is not defined, but it works */
 746         if ((desc->desc.bInterfaceSubClass != 0) &&
 747             (desc->desc.bInterfaceSubClass != 1)) {
 748 descriptor_error:
 749                 dev_err (hub_dev, "bad descriptor, ignoring hub\n");
 750                 return -EIO;
 751         }
 752
 753         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
 754         if (desc->desc.bNumEndpoints != 1)
 755                 goto descriptor_error;
 756
 757         endpoint = &desc->endpoint[0].desc;
 758
 759         /* Output endpoint? Curiouser and curiouser.. */
 760         if (!(endpoint->bEndpointAddress & USB_DIR_IN))
 761                 goto descriptor_error;
 762
 763         /* If it's not an interrupt endpoint, we'd better punt! */
 764         if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
 765                         != USB_ENDPOINT_XFER_INT)
 766                 goto descriptor_error;
 767
 768         /* We found a hub */
 769         dev_info (hub_dev, "USB hub found\n");
 770
 771         hub = kmalloc(sizeof(*hub), GFP_KERNEL);
 772         if (!hub) {
 773                 dev_dbg (hub_dev, "couldn't kmalloc hub struct\n");
 774                 return -ENOMEM;
 775         }
 776
 777         memset(hub, 0, sizeof(*hub));
 778
 779         INIT_LIST_HEAD(&hub->event_list);
 780         hub->intf = intf;
 781         hub->hdev = hdev;
 782         INIT_WORK(&hub->leds, led_work, hub);
 783
 784         usb_set_intfdata (intf, hub);
 785
 786         if (hdev->speed == USB_SPEED_HIGH)
 787                 highspeed_hubs++;
 788
 789         if (hub_configure(hub, endpoint) >= 0)
 790                 return 0;
 791
 792         hub_disconnect (intf);
 793         return -ENODEV;
 794 }
 795
 796 static int
 797 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
 798 {
 799         struct usb_device *hdev = interface_to_usbdev (intf);
 800
 801         /* assert ifno == 0 (part of hub spec) */
 802         switch (code) {
 803         case USBDEVFS_HUB_PORTINFO: {
 804                 struct usbdevfs_hub_portinfo *info = user_data;
 805                 unsigned long flags;
 806                 int i;
 807
 808                 spin_lock_irqsave(&hub_event_lock, flags);
 809                 if (hdev->devnum <= 0)
 810                         info->nports = 0;
 811                 else {
 812                         info->nports = hdev->maxchild;
 813                         for (i = 0; i < info->nports; i++) {
 814                                 if (hdev->children[i] == NULL)
 815                                         info->port[i] = 0;
 816                                 else
 817                                         info->port[i] =
 818                                                 hdev->children[i]->devnum;
 819                         }
 820                 }
 821                 spin_unlock_irqrestore(&hub_event_lock, flags);
 822
 823                 return info->nports + 1;
 824                 }
 825
 826         default:
 827                 return -ENOSYS;
 828         }
 829 }
 830
 831 /* caller has locked the hub device */
 832 static void hub_pre_reset(struct usb_device *hdev)
 833 {
 834         struct usb_hub *hub = usb_get_intfdata(hdev->actconfig->interface[0]);
 835         int i;
 836
 837         for (i = 0; i < hdev->maxchild; ++i) {
 838                 if (hdev->children[i])
 839                         usb_disconnect(&hdev->children[i]);
 840         }
 841         hub_quiesce(hub);
 842 }
 843
 844 /* caller has locked the hub device */
 845 static void hub_post_reset(struct usb_device *hdev)
 846 {
 847         struct usb_hub *hub = usb_get_intfdata(hdev->actconfig->interface[0]);
 848
 849         hub_activate(hub);
 850         hub_power_on(hub);
 851 }
 852
 853
 854 /* grab device/port lock, returning index of that port (zero based).
 855  * protects the upstream link used by this device from concurrent
 856  * tree operations like suspend, resume, reset, and disconnect, which
 857  * apply to everything downstream of a given port.
 858  */
 859 static int locktree(struct usb_device *udev)
 860 {
 861         int                     t;
 862         struct usb_device       *hdev;
 863
 864         if (!udev)
 865                 return -ENODEV;
 866
 867         /* root hub is always the first lock in the series */
 868         hdev = udev->parent;
 869         if (!hdev) {
 870                 usb_lock_device(udev);
 871                 return 0;
 872         }
 873
 874         /* on the path from root to us, lock everything from
 875          * top down, dropping parent locks when not needed
 876          */
 877         t = locktree(hdev);
 878         if (t < 0)
 879                 return t;
 880         for (t = 0; t < hdev->maxchild; t++) {
 881                 if (hdev->children[t] == udev) {
 882                         /* everything is fail-fast once disconnect
 883                          * processing starts
 884                          */
 885                         if (udev->state == USB_STATE_NOTATTACHED)
 886                                 break;
 887
 888                         /* when everyone grabs locks top->bottom,
 889                          * non-overlapping work may be concurrent
 890                          */
 891                         down(&udev->serialize);
 892                         up(&hdev->serialize);
 893                         return t;
 894                 }
 895         }
 896         usb_unlock_device(hdev);
 897         return -ENODEV;
 898 }
 899
 900 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
 901 {
 902         int i;
 903
 904         for (i = 0; i < udev->maxchild; ++i) {
 905                 if (udev->children[i])
 906                         recursively_mark_NOTATTACHED(udev->children[i]);
 907         }
 908         udev->state = USB_STATE_NOTATTACHED;
 909 }
 910
 911 /**
 912  * usb_set_device_state - change a device's current state (usbcore, hcds)
 913  * @udev: pointer to device whose state should be changed
 914  * @new_state: new state value to be stored
 915  *
 916  * udev->state is _not_ fully protected by the device lock.  Although
 917  * most transitions are made only while holding the lock, the state can
 918  * can change to USB_STATE_NOTATTACHED at almost any time.  This
 919  * is so that devices can be marked as disconnected as soon as possible,
 920  * without having to wait for any semaphores to be released.  As a result,
 921  * all changes to any device's state must be protected by the
 922  * device_state_lock spinlock.
 923  *
 924  * Once a device has been added to the device tree, all changes to its state
 925  * should be made using this routine.  The state should _not_ be set directly.
 926  *
 927  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
 928  * Otherwise udev->state is set to new_state, and if new_state is
 929  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
 930  * to USB_STATE_NOTATTACHED.
 931  */
 932 void usb_set_device_state(struct usb_device *udev,
 933                 enum usb_device_state new_state)
 934 {
 935         unsigned long flags;
 936
 937         spin_lock_irqsave(&device_state_lock, flags);
 938         if (udev->state == USB_STATE_NOTATTACHED)
 939                 ;       /* do nothing */
 940         else if (new_state != USB_STATE_NOTATTACHED)
 941                 udev->state = new_state;
 942         else
 943                 recursively_mark_NOTATTACHED(udev);
 944         spin_unlock_irqrestore(&device_state_lock, flags);
 945 }
 946 EXPORT_SYMBOL(usb_set_device_state);
 947
 948
 949 static void choose_address(struct usb_device *udev)
 950 {
 951         int             devnum;
 952         struct usb_bus  *bus = udev->bus;
 953
 954         /* If khubd ever becomes multithreaded, this will need a lock */
 955
 956         /* Try to allocate the next devnum beginning at bus->devnum_next. */
 957         devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
 958                         bus->devnum_next);
 959         if (devnum >= 128)
 960                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
 961
 962         bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
 963
 964         if (devnum < 128) {
 965                 set_bit(devnum, bus->devmap.devicemap);
 966                 udev->devnum = devnum;
 967         }
 968 }
 969
 970 static void release_address(struct usb_device *udev)
 971 {
 972         if (udev->devnum > 0) {
 973                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
 974                 udev->devnum = -1;
 975         }
 976 }
 977
 978 /**
 979  * usb_disconnect - disconnect a device (usbcore-internal)
 980  * @pdev: pointer to device being disconnected
 981  * Context: !in_interrupt ()
 982  *
 983  * Something got disconnected. Get rid of it and all of its children.
 984  *
 985  * If *pdev is a normal device then the parent hub must already be locked.
 986  * If *pdev is a root hub then this routine will acquire the
 987  * usb_bus_list_lock on behalf of the caller.
 988  *
 989  * Only hub drivers (including virtual root hub drivers for host
 990  * controllers) should ever call this.
 991  *
 992  * This call is synchronous, and may not be used in an interrupt context.
 993  */
 994 void usb_disconnect(struct usb_device **pdev)
 995 {
 996         struct usb_device       *udev = *pdev;
 997         int                     i;
 998
 999         if (!udev) {
1000                 pr_debug ("%s nodev\n", __FUNCTION__);
1001                 return;
1002         }
1003
1004         /* mark the device as inactive, so any further urb submissions for
1005          * this device (and any of its children) will fail immediately.
1006          * this quiesces everyting except pending urbs.
1007          */
1008         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1009
1010         /* lock the bus list on behalf of HCDs unregistering their root hubs */
1011         if (!udev->parent) {
1012                 down(&usb_bus_list_lock);
1013                 usb_lock_device(udev);
1014         } else
1015                 down(&udev->serialize);
1016
1017         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1018
1019         /* Free up all the children before we remove this device */
1020         for (i = 0; i < USB_MAXCHILDREN; i++) {
1021                 if (udev->children[i])
1022                         usb_disconnect(&udev->children[i]);
1023         }
1024
1025         /* deallocate hcd/hardware state ... nuking all pending urbs and
1026          * cleaning up all state associated with the current configuration
1027          * so that the hardware is now fully quiesced.
1028          */
1029         usb_disable_device(udev, 0);
1030
1031         /* Free the device number, remove the /proc/bus/usb entry and
1032          * the sysfs attributes, and delete the parent's children[]
1033          * (or root_hub) pointer.
1034          */
1035         dev_dbg (&udev->dev, "unregistering device\n");
1036         release_address(udev);
1037         usbfs_remove_device(udev);
1038         usb_remove_sysfs_dev_files(udev);
1039
1040         /* Avoid races with recursively_mark_NOTATTACHED() */
1041         spin_lock_irq(&device_state_lock);
1042         *pdev = NULL;
1043         spin_unlock_irq(&device_state_lock);
1044
1045         if (!udev->parent) {
1046                 usb_unlock_device(udev);
1047                 up(&usb_bus_list_lock);
1048         } else
1049                 up(&udev->serialize);
1050
1051         device_unregister(&udev->dev);
1052 }
1053
1054 static int choose_configuration(struct usb_device *udev)
1055 {
1056         int c, i;
1057
1058         /* NOTE: this should interact with hub power budgeting */
1059
1060         c = udev->config[0].desc.bConfigurationValue;
1061         if (udev->descriptor.bNumConfigurations != 1) {
1062                 for (i = 0; i < udev->descriptor.bNumConfigurations; i++) {
1063                         struct usb_interface_descriptor *desc;
1064
1065                         /* heuristic:  Linux is more likely to have class
1066                          * drivers, so avoid vendor-specific interfaces.
1067                          */
1068                         desc = &udev->config[i].intf_cache[0]
1069                                         ->altsetting->desc;
1070                         if (desc->bInterfaceClass == USB_CLASS_VENDOR_SPEC)
1071                                 continue;
1072                         /* COMM/2/all is CDC ACM, except 0xff is MSFT RNDIS.
1073                          * MSFT needs this to be the first config; never use
1074                          * it as the default unless Linux has host-side RNDIS.
1075                          * A second config would ideally be CDC-Ethernet, but
1076                          * may instead be the "vendor specific" CDC subset
1077                          * long used by ARM Linux for sa1100 or pxa255.
1078                          */
1079                         if (desc->bInterfaceClass == USB_CLASS_COMM
1080                                         && desc->bInterfaceSubClass == 2
1081                                         && desc->bInterfaceProtocol == 0xff) {
1082                                 c = udev->config[1].desc.bConfigurationValue;
1083                                 continue;
1084                         }
1085                         c = udev->config[i].desc.bConfigurationValue;
1086                         break;
1087                 }
1088                 dev_info(&udev->dev,
1089                         "configuration #%d chosen from %d choices\n",
1090                         c, udev->descriptor.bNumConfigurations);
1091         }
1092         return c;
1093 }
1094
1095 #ifdef DEBUG
1096 static void show_string(struct usb_device *udev, char *id, int index)
1097 {
1098         char *buf;
1099
1100         if (!index)
1101                 return;
1102         if (!(buf = kmalloc(256, GFP_KERNEL)))
1103                 return;
1104         if (usb_string(udev, index, buf, 256) > 0)
1105                 dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, buf);
1106         kfree(buf);
1107 }
1108
1109 #else
1110 static inline void show_string(struct usb_device *udev, char *id, int index)
1111 {}
1112 #endif
1113
1114 #ifdef  CONFIG_USB_OTG
1115 #include "otg_whitelist.h"
1116 #endif
1117
1118 /**
1119  * usb_new_device - perform initial device setup (usbcore-internal)
1120  * @udev: newly addressed device (in ADDRESS state)
1121  *
1122  * This is called with devices which have been enumerated, but not yet
1123  * configured.  The device descriptor is available, but not descriptors
1124  * for any device configuration.  The caller must have locked udev and
1125  * either the parent hub (if udev is a normal device) or else the
1126  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1127  * udev has already been installed, but udev is not yet visible through
1128  * sysfs or other filesystem code.
1129  *
1130  * Returns 0 for success (device is configured and listed, with its
1131  * interfaces, in sysfs); else a negative errno value.
1132  *
1133  * This call is synchronous, and may not be used in an interrupt context.
1134  *
1135  * Only the hub driver should ever call this; root hub registration
1136  * uses it indirectly.
1137  */
1138 int usb_new_device(struct usb_device *udev)
1139 {
1140         int err;
1141         int c;
1142
1143         err = usb_get_configuration(udev);
1144         if (err < 0) {
1145                 dev_err(&udev->dev, "can't read configurations, error %d\n",
1146                         err);
1147                 goto fail;
1148         }
1149
1150         /* Tell the world! */
1151         dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1152                         "SerialNumber=%d\n",
1153                         udev->descriptor.iManufacturer,
1154                         udev->descriptor.iProduct,
1155                         udev->descriptor.iSerialNumber);
1156
1157         if (udev->descriptor.iProduct)
1158                 show_string(udev, "Product",
1159                                 udev->descriptor.iProduct);
1160         if (udev->descriptor.iManufacturer)
1161                 show_string(udev, "Manufacturer",
1162                                 udev->descriptor.iManufacturer);
1163         if (udev->descriptor.iSerialNumber)
1164                 show_string(udev, "SerialNumber",
1165                                 udev->descriptor.iSerialNumber);
1166
1167 #ifdef  CONFIG_USB_OTG
1168         /*
1169          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1170          * to wake us after we've powered off VBUS; and HNP, switching roles
1171          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1172          */
1173         if (!udev->bus->is_b_host
1174                         && udev->config
1175                         && udev->parent == udev->bus->root_hub) {
1176                 struct usb_otg_descriptor       *desc = 0;
1177                 struct usb_bus                  *bus = udev->bus;
1178
1179                 /* descriptor may appear anywhere in config */
1180                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1181                                         udev->config[0].desc.wTotalLength,
1182                                         USB_DT_OTG, (void **) &desc) == 0) {
1183                         if (desc->bmAttributes & USB_OTG_HNP) {
1184                                 unsigned                port;
1185                                 struct usb_device       *root = udev->parent;
1186
1187                                 for (port = 0; port < root->maxchild; port++) {
1188                                         if (root->children[port] == udev)
1189                                                 break;
1190                                 }
1191                                 port++;
1192
1193                                 dev_info(&udev->dev,
1194                                         "Dual-Role OTG device on %sHNP port\n",
1195                                         (port == bus->otg_port)
1196                                                 ? "" : "non-");
1197
1198                                 /* enable HNP before suspend, it's simpler */
1199                                 if (port == bus->otg_port)
1200                                         bus->b_hnp_enable = 1;
1201                                 err = usb_control_msg(udev,
1202                                         usb_sndctrlpipe(udev, 0),
1203                                         USB_REQ_SET_FEATURE, 0,
1204                                         bus->b_hnp_enable
1205                                                 ? USB_DEVICE_B_HNP_ENABLE
1206                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1207                                         0, NULL, 0, HZ * USB_CTRL_SET_TIMEOUT);
1208                                 if (err < 0) {
1209                                         /* OTG MESSAGE: report errors here,
1210                                          * customize to match your product.
1211                                          */
1212                                         dev_info(&udev->dev,
1213                                                 "can't set HNP mode; %d\n",
1214                                                 err);
1215                                         bus->b_hnp_enable = 0;
1216                                 }
1217                         }
1218                 }
1219         }
1220
1221         if (!is_targeted(udev)) {
1222
1223                 /* Maybe it can talk to us, though we can't talk to it.
1224                  * (Includes HNP test device.)
1225                  */
1226                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1227                         static int __usb_suspend_device (struct usb_device *,
1228                                                 int port, u32 state);
1229                         err = __usb_suspend_device(udev,
1230                                         udev->bus->otg_port - 1,
1231                                         PM_SUSPEND_MEM);
1232                         if (err < 0)
1233                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1234                 }
1235                 err = -ENODEV;
1236                 goto fail;
1237         }
1238 #endif
1239
1240         /* put device-specific files into sysfs */
1241         err = device_add (&udev->dev);
1242         if (err) {
1243                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1244                 goto fail;
1245         }
1246         usb_create_sysfs_dev_files (udev);
1247
1248         /* choose and set the configuration. that registers the interfaces
1249          * with the driver core, and lets usb device drivers bind to them.
1250          */
1251         c = choose_configuration(udev);
1252         if (c < 0)
1253                 dev_warn(&udev->dev,
1254                                 "can't choose an initial configuration\n");
1255         else {
1256                 err = usb_set_configuration(udev, c);
1257                 if (err) {
1258                         dev_err(&udev->dev, "can't set config #%d, error %d\n",
1259                                         c, err);
1260                         usb_remove_sysfs_dev_files(udev);
1261                         device_del(&udev->dev);
1262                         goto fail;
1263                 }
1264         }
1265
1266         /* USB device state == configured ... usable */
1267
1268         /* add a /proc/bus/usb entry */
1269         usbfs_add_device(udev);
1270         return 0;
1271
1272 fail:
1273         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1274         return err;
1275 }
1276
1277
1278 static int hub_port_status(struct usb_device *hdev, int port,
1279                                u16 *status, u16 *change)
1280 {
1281         struct usb_hub *hub = usb_get_intfdata(hdev->actconfig->interface[0]);
1282         int ret;
1283
1284         if (!hub)
1285                 return -ENODEV;
1286
1287         ret = get_port_status(hdev, port + 1, &hub->status->port);
1288         if (ret < 0)
1289                 dev_err (&hub->intf->dev,
1290                         "%s failed (err = %d)\n", __FUNCTION__, ret);
1291         else {
1292                 *status = le16_to_cpu(hub->status->port.wPortStatus);
1293                 *change = le16_to_cpu(hub->status->port.wPortChange);
1294                 ret = 0;
1295         }
1296         return ret;
1297 }
1298
1299 #define PORT_RESET_TRIES        5
1300 #define SET_ADDRESS_TRIES       2
1301 #define GET_DESCRIPTOR_TRIES    2
1302 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1303 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1304
1305 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1306 #define HUB_SHORT_RESET_TIME    10
1307 #define HUB_LONG_RESET_TIME     200
1308 #define HUB_RESET_TIMEOUT       500
1309
1310 static int hub_port_wait_reset(struct usb_device *hdev, int port,
1311                                 struct usb_device *udev, unsigned int delay)
1312 {
1313         int delay_time, ret;
1314         u16 portstatus;
1315         u16 portchange;
1316
1317         for (delay_time = 0;
1318                         delay_time < HUB_RESET_TIMEOUT;
1319                         delay_time += delay) {
1320                 /* wait to give the device a chance to reset */
1321                 msleep(delay);
1322
1323                 /* read and decode port status */
1324                 ret = hub_port_status(hdev, port, &portstatus, &portchange);
1325                 if (ret < 0)
1326                         return ret;
1327
1328                 /* Device went away? */
1329                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1330                         return -ENOTCONN;
1331
1332                 /* bomb out completely if something weird happened */
1333                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1334                         return -EINVAL;
1335
1336                 /* if we`ve finished resetting, then break out of the loop */
1337                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1338                     (portstatus & USB_PORT_STAT_ENABLE)) {
1339                         if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1340                                 udev->speed = USB_SPEED_HIGH;
1341                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1342                                 udev->speed = USB_SPEED_LOW;
1343                         else
1344                                 udev->speed = USB_SPEED_FULL;
1345                         return 0;
1346                 }
1347
1348                 /* switch to the long delay after two short delay failures */
1349                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1350                         delay = HUB_LONG_RESET_TIME;
1351
1352                 dev_dbg (hubdev (hdev),
1353                         "port %d not reset yet, waiting %dms\n",
1354                         port + 1, delay);
1355         }
1356
1357         return -EBUSY;
1358 }
1359
1360 static int hub_port_reset(struct usb_device *hdev, int port,
1361                                 struct usb_device *udev, unsigned int delay)
1362 {
1363         int i, status;
1364         struct device *hub_dev = hubdev (hdev);
1365
1366         /* Reset the port */
1367         for (i = 0; i < PORT_RESET_TRIES; i++) {
1368                 status = set_port_feature(hdev, port + 1, USB_PORT_FEAT_RESET);
1369                 if (status)
1370                         dev_err(hub_dev, "cannot reset port %d (err = %d)\n",
1371                                         port + 1, status);
1372                 else
1373                         status = hub_port_wait_reset(hdev, port, udev, delay);
1374
1375                 /* return on disconnect or reset */
1376                 switch (status) {
1377                 case 0:
1378                 case -ENOTCONN:
1379                 case -ENODEV:
1380                         clear_port_feature(hdev,
1381                                 port + 1, USB_PORT_FEAT_C_RESET);
1382                         /* FIXME need disconnect() for NOTATTACHED device */
1383                         usb_set_device_state(udev, status
1384                                         ? USB_STATE_NOTATTACHED
1385                                         : USB_STATE_DEFAULT);
1386                         return status;
1387                 }
1388
1389                 dev_dbg (hub_dev,
1390                         "port %d not enabled, trying reset again...\n",
1391                         port + 1);
1392                 delay = HUB_LONG_RESET_TIME;
1393         }
1394
1395         dev_err (hub_dev,
1396                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1397                 port + 1);
1398
1399         return status;
1400 }
1401
1402 static int hub_port_disable(struct usb_device *hdev, int port)
1403 {
1404         int ret;
1405
1406         if (hdev->children[port]) {
1407                 usb_set_device_state(hdev->children[port],
1408                                 USB_STATE_NOTATTACHED);
1409         }
1410         ret = clear_port_feature(hdev, port + 1, USB_PORT_FEAT_ENABLE);
1411         if (ret)
1412                 dev_err(hubdev(hdev), "cannot disable port %d (err = %d)\n",
1413                         port + 1, ret);
1414
1415         return ret;
1416 }
1417
1418 /*
1419  * Disable a port and mark a logical connnect-change event, so that some
1420  * time later khubd will disconnect() any existing usb_device on the port
1421  * and will re-enumerate if there actually is a device attached.
1422  */
1423 static void hub_port_logical_disconnect(struct usb_device *hdev, int port)
1424 {
1425         struct usb_hub *hub;
1426
1427         dev_dbg(hubdev(hdev), "logical disconnect on port %d\n", port + 1);
1428         hub_port_disable(hdev, port);
1429
1430         /* FIXME let caller ask to power down the port:
1431          *  - some devices won't enumerate without a VBUS power cycle
1432          *  - SRP saves power that way
1433          *  - usb_suspend_device(dev,PM_SUSPEND_DISK)
1434          * That's easy if this hub can switch power per-port, and
1435          * khubd reactivates the port later (timer, SRP, etc).
1436          * Powerdown must be optional, because of reset/DFU.
1437          */
1438
1439         hub = usb_get_intfdata(hdev->actconfig->interface[0]);
1440         set_bit(port, hub->change_bits);
1441         kick_khubd(hub);
1442 }
1443
1444
1445 #ifdef  CONFIG_USB_SUSPEND
1446
1447 /*
1448  * Selective port suspend reduces power; most suspended devices draw
1449  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1450  * All devices below the suspended port are also suspended.
1451  *
1452  * Devices leave suspend state when the host wakes them up.  Some devices
1453  * also support "remote wakeup", where the device can activate the USB
1454  * tree above them to deliver data, such as a keypress or packet.  In
1455  * some cases, this wakes the USB host.
1456  */
1457 static int hub_port_suspend(struct usb_device *hdev, int port)
1458 {
1459         int                     status;
1460         struct usb_device       *udev;
1461
1462         udev = hdev->children[port];
1463         // dev_dbg(hubdev(hdev), "suspend port %d\n", port + 1);
1464
1465         /* enable remote wakeup when appropriate; this lets the device
1466          * wake up the upstream hub (including maybe the root hub).
1467          *
1468          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1469          * we don't explicitly enable it here.
1470          */
1471         if (udev->actconfig
1472                         // && FIXME (remote wakeup enabled on this bus)
1473                         // ... currently assuming it's always appropriate
1474                         && (udev->actconfig->desc.bmAttributes
1475                                 & USB_CONFIG_ATT_WAKEUP) != 0) {
1476                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1477                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1478                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1479                                 NULL, 0,
1480                                 USB_CTRL_SET_TIMEOUT);
1481                 if (status)
1482                         dev_dbg(&udev->dev,
1483                                 "won't remote wakeup, status %d\n",
1484                                 status);
1485         }
1486
1487         /* see 7.1.7.6 */
1488         status = set_port_feature(hdev, port + 1, USB_PORT_FEAT_SUSPEND);
1489         if (status) {
1490                 dev_dbg(hubdev(hdev),
1491                         "can't suspend port %d, status %d\n",
1492                         port + 1, status);
1493                 /* paranoia:  "should not happen" */
1494                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1495                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1496                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1497                                 NULL, 0,
1498                                 USB_CTRL_SET_TIMEOUT);
1499         } else {
1500                 /* device has up to 10 msec to fully suspend */
1501                 dev_dbg(&udev->dev, "usb suspend\n");
1502                 udev->state = USB_STATE_SUSPENDED;
1503                 msleep(10);
1504         }
1505         return status;
1506 }
1507
1508 /*
1509  * Devices on USB hub ports have only one "suspend" state, corresponding
1510  * to ACPI D2 (PM_SUSPEND_MEM), "may cause the device to lose some context".
1511  * State transitions include:
1512  *
1513  *   - suspend, resume ... when the VBUS power link stays live
1514  *   - suspend, disconnect ... VBUS lost
1515  *
1516  * Once VBUS drop breaks the circuit, the port it's using has to go through
1517  * normal re-enumeration procedures, starting with enabling VBUS power.
1518  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1519  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1520  * timer, no SRP, no requests through sysfs.
1521  */
1522 int __usb_suspend_device (struct usb_device *udev, int port, u32 state)
1523 {
1524         int     status;
1525
1526         /* caller owns the udev device lock */
1527         if (port < 0)
1528                 return port;
1529
1530         if (udev->state == USB_STATE_SUSPENDED
1531                         || udev->state == USB_STATE_NOTATTACHED) {
1532                 return 0;
1533         }
1534
1535         /* suspend interface drivers; if this is a hub, it
1536          * suspends the child devices
1537          */
1538         if (udev->actconfig) {
1539                 int     i;
1540
1541                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1542                         struct usb_interface    *intf;
1543                         struct usb_driver       *driver;
1544
1545                         intf = udev->actconfig->interface[i];
1546                         if (state <= intf->dev.power.power_state)
1547                                 continue;
1548                         if (!intf->dev.driver)
1549                                 continue;
1550                         driver = to_usb_driver(intf->dev.driver);
1551
1552                         if (driver->suspend) {
1553                                 status = driver->suspend(intf, state);
1554                                 if (intf->dev.power.power_state != state
1555                                                 || status)
1556                                         dev_err(&intf->dev,
1557                                                 "suspend %d fail, code %d\n",
1558                                                 state, status);
1559                         }
1560
1561                         /* only drivers with suspend() can ever resume();
1562                          * and after power loss, even they won't.
1563                          * bus_rescan_devices() can rebind drivers later.
1564                          *
1565                          * FIXME the PM core self-deadlocks when unbinding
1566                          * drivers during suspend/resume ... everything grabs
1567                          * dpm_sem (not a spinlock, ugh).  we want to unbind,
1568                          * since we know every driver's probe/disconnect works
1569                          * even for drivers that can't suspend.
1570                          */
1571                         if (!driver->suspend || state > PM_SUSPEND_MEM) {
1572 #if 1
1573                                 dev_warn(&intf->dev, "resume is unsafe!\n");
1574 #else
1575                                 down_write(&usb_bus_type.rwsem);
1576                                 device_release_driver(&intf->dev);
1577                                 up_write(&usb_bus_type.rwsem);
1578 #endif
1579                         }
1580                 }
1581         }
1582
1583         /*
1584          * FIXME this needs port power off call paths too, to help force
1585          * USB into the "generic" PM model.  At least for devices on
1586          * ports that aren't using ganged switching (usually root hubs).
1587          *
1588          * NOTE: SRP-capable links should adopt more aggressive poweroff
1589          * policies (when HNP doesn't apply) once we have mechanisms to
1590          * turn power back on!  (Likely not before 2.7...)
1591          */
1592         if (state > PM_SUSPEND_MEM) {
1593                 dev_warn(&udev->dev, "no poweroff yet, suspending instead\n");
1594         }
1595
1596         /* "global suspend" of the HC-to-USB interface (root hub), or
1597          * "selective suspend" of just one hub-device link.
1598          */
1599         if (!udev->parent) {
1600                 struct usb_bus  *bus = udev->bus;
1601                 if (bus && bus->op->hub_suspend) {
1602                         status = bus->op->hub_suspend (bus);
1603                         if (status == 0)
1604                                 usb_set_device_state(udev,
1605                                                 USB_STATE_SUSPENDED);
1606                 } else
1607                         status = -EOPNOTSUPP;
1608         } else
1609                 status = hub_port_suspend(udev->parent, port);
1610
1611         return status;
1612 }
1613 EXPORT_SYMBOL(__usb_suspend_device);
1614
1615 /**
1616  * usb_suspend_device - suspend a usb device
1617  * @udev: device that's no longer in active use
1618  * @state: PM_SUSPEND_MEM to suspend
1619  * Context: must be able to sleep; device not locked
1620  *
1621  * Suspends a USB device that isn't in active use, conserving power.
1622  * Devices may wake out of a suspend, if anything important happens,
1623  * using the remote wakeup mechanism.  They may also be taken out of
1624  * suspend by the host, using usb_resume_device().  It's also routine
1625  * to disconnect devices while they are suspended.
1626  *
1627  * Suspending OTG devices may trigger HNP, if that's been enabled
1628  * between a pair of dual-role devices.  That will change roles, such
1629  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1630  *
1631  * Returns 0 on success, else negative errno.
1632  */
1633 int usb_suspend_device(struct usb_device *udev, u32 state)
1634 {
1635         int     port, status;
1636
1637         port = locktree(udev);
1638         if (port < 0)
1639                 return port;
1640
1641         status = __usb_suspend_device(udev, port, state);
1642         usb_unlock_device(udev);
1643         return status;
1644 }
1645
1646 /*
1647  * hardware resume signaling is finished, either because of selective
1648  * resume (by host) or remote wakeup (by device) ... now see what changed
1649  * in the tree that's rooted at this device.
1650  */
1651 static int finish_port_resume(struct usb_device *udev)
1652 {
1653         int     status;
1654         u16     devstatus;
1655
1656         /* caller owns the udev device lock */
1657         dev_dbg(&udev->dev, "usb resume\n");
1658
1659         /* usb ch9 identifies four variants of SUSPENDED, based on what
1660          * state the device resumes to.  Linux currently won't see the
1661          * first two on the host side; they'd be inside hub_port_init()
1662          * during many timeouts, but khubd can't suspend until later.
1663          */
1664         udev->state = udev->actconfig
1665                 ? USB_STATE_CONFIGURED
1666                 : USB_STATE_ADDRESS;
1667
1668         /* 10.5.4.5 says be sure devices in the tree are still there.
1669          * For now let's assume the device didn't go crazy on resume,
1670          * and device drivers will know about any resume quirks.
1671          */
1672         status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1673         if (status < 0)
1674                 dev_dbg(&udev->dev,
1675                         "gone after usb resume? status %d\n",
1676                         status);
1677         else if (udev->actconfig) {
1678                 unsigned        i;
1679
1680                 le16_to_cpus(&devstatus);
1681                 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
1682                         status = usb_control_msg(udev,
1683                                         usb_sndctrlpipe(udev, 0),
1684                                         USB_REQ_CLEAR_FEATURE,
1685                                                 USB_RECIP_DEVICE,
1686                                         USB_DEVICE_REMOTE_WAKEUP, 0,
1687                                         NULL, 0,
1688                                         USB_CTRL_SET_TIMEOUT);
1689                         if (status) {
1690                                 dev_dbg(&udev->dev, "disable remote "
1691                                         "wakeup, status %d\n", status);
1692                                 status = 0;
1693                         }
1694                 }
1695
1696                 /* resume interface drivers; if this is a hub, it
1697                  * resumes the child devices
1698                  */
1699                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1700                         struct usb_interface    *intf;
1701                         struct usb_driver       *driver;
1702
1703                         intf = udev->actconfig->interface[i];
1704                         if (intf->dev.power.power_state == PM_SUSPEND_ON)
1705                                 continue;
1706                         if (!intf->dev.driver) {
1707                                 /* FIXME maybe force to alt 0 */
1708                                 continue;
1709                         }
1710                         driver = to_usb_driver(intf->dev.driver);
1711
1712                         /* bus_rescan_devices() may rebind drivers */
1713                         if (!driver->resume)
1714                                 continue;
1715
1716                         /* can we do better than just logging errors? */
1717                         status = driver->resume(intf);
1718                         if (intf->dev.power.power_state != PM_SUSPEND_ON
1719                                         || status)
1720                                 dev_dbg(&intf->dev,
1721                                         "resume fail, state %d code %d\n",
1722                                         intf->dev.power.power_state, status);
1723                 }
1724                 status = 0;
1725
1726         } else if (udev->devnum <= 0) {
1727                 dev_dbg(&udev->dev, "bogus resume!\n");
1728                 status = -EINVAL;
1729         }
1730         return status;
1731 }
1732
1733 static int
1734 hub_port_resume(struct usb_device *hdev, int port)
1735 {
1736         int                     status;
1737         struct usb_device       *udev;
1738
1739         udev = hdev->children[port];
1740         // dev_dbg(hubdev(hdev), "resume port %d\n", port + 1);
1741
1742         /* see 7.1.7.7; affects power usage, but not budgeting */
1743         status = clear_port_feature(hdev, port + 1, USB_PORT_FEAT_SUSPEND);
1744         if (status) {
1745                 dev_dbg(&hdev->actconfig->interface[0]->dev,
1746                         "can't resume port %d, status %d\n",
1747                         port + 1, status);
1748         } else {
1749                 u16             devstatus;
1750                 u16             portchange;
1751
1752                 /* drive resume for at least 20 msec */
1753                 dev_dbg(&udev->dev, "RESUME\n");
1754                 msleep(25);
1755
1756 #define LIVE_FLAGS      ( USB_PORT_STAT_POWER \
1757                         | USB_PORT_STAT_ENABLE \
1758                         | USB_PORT_STAT_CONNECTION)
1759
1760                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1761                  * stop resume signaling.  Then finish the resume
1762                  * sequence.
1763                  */
1764                 devstatus = portchange = 0;
1765                 status = hub_port_status(hdev, port,
1766                                 &devstatus, &portchange);
1767                 if (status < 0
1768                                 || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
1769                                 || (devstatus & USB_PORT_STAT_SUSPEND) != 0
1770                                 ) {
1771                         dev_dbg(&hdev->actconfig->interface[0]->dev,
1772                                 "port %d status %04x.%04x after resume, %d\n",
1773                                 port + 1, portchange, devstatus, status);
1774                 } else {
1775                         /* TRSMRCY = 10 msec */
1776                         msleep(10);
1777                         status = finish_port_resume(udev);
1778                 }
1779         }
1780         if (status < 0)
1781                 hub_port_logical_disconnect(hdev, port);
1782
1783         return status;
1784 }
1785
1786 static int hub_resume (struct usb_interface *intf);
1787
1788 /**
1789  * usb_resume_device - re-activate a suspended usb device
1790  * @udev: device to re-activate
1791  * Context: must be able to sleep; device not locked
1792  *
1793  * This will re-activate the suspended device, increasing power usage
1794  * while letting drivers communicate again with its endpoints.
1795  * USB resume explicitly guarantees that the power session between
1796  * the host and the device is the same as it was when the device
1797  * suspended.
1798  *
1799  * Returns 0 on success, else negative errno.
1800  */
1801 int usb_resume_device(struct usb_device *udev)
1802 {
1803         int                     port, status;
1804
1805         port = locktree(udev);
1806         if (port < 0)
1807                 return port;
1808
1809         /* "global resume" of the HC-to-USB interface (root hub), or
1810          * selective resume of one hub-to-device port
1811          */
1812         if (!udev->parent) {
1813                 struct usb_bus  *bus = udev->bus;
1814                 if (bus && bus->op->hub_resume) {
1815                         status = bus->op->hub_resume (bus);
1816                 } else
1817                         status = -EOPNOTSUPP;
1818                 if (status == 0) {
1819                         /* TRSMRCY = 10 msec */
1820                         msleep(10);
1821                         usb_set_device_state (udev, USB_STATE_CONFIGURED);
1822                         status = hub_resume (udev
1823                                         ->actconfig->interface[0]);
1824                 }
1825         } else if (udev->state == USB_STATE_SUSPENDED) {
1826                 // NOTE this fails if parent is also suspended...
1827                 status = hub_port_resume(udev->parent, port);
1828         } else {
1829                 status = 0;
1830         }
1831         if (status < 0) {
1832                 dev_dbg(&udev->dev, "can't resume, status %d\n",
1833                         status);
1834         }
1835
1836         usb_unlock_device(udev);
1837
1838         /* rebind drivers that had no suspend() */
1839         if (status == 0) {
1840                 usb_lock_all_devices();
1841                 bus_rescan_devices(&usb_bus_type);
1842                 usb_unlock_all_devices();
1843         }
1844         return status;
1845 }
1846
1847 static int remote_wakeup(struct usb_device *udev)
1848 {
1849         int     status = 0;
1850
1851         /* don't repeat RESUME sequence if this device
1852          * was already woken up by some other task
1853          */
1854         down(&udev->serialize);
1855         if (udev->state == USB_STATE_SUSPENDED) {
1856                 dev_dbg(&udev->dev, "RESUME (wakeup)\n");
1857                 /* TRSMRCY = 10 msec */
1858                 msleep(10);
1859                 status = finish_port_resume(udev);
1860         }
1861         up(&udev->serialize);
1862         return status;
1863 }
1864
1865 static int hub_suspend(struct usb_interface *intf, u32 state)
1866 {
1867         struct usb_hub          *hub = usb_get_intfdata (intf);
1868         struct usb_device       *hdev = hub->hdev;
1869         unsigned                port;
1870         int                     status;
1871
1872         /* stop khubd and related activity */
1873         hub_quiesce(hub);
1874
1875         /* then suspend every port */
1876         for (port = 0; port < hdev->maxchild; port++) {
1877                 struct usb_device       *udev;
1878
1879                 udev = hdev->children [port];
1880                 if (!udev)
1881                         continue;
1882                 down(&udev->serialize);
1883                 status = __usb_suspend_device(udev, port, state);
1884                 up(&udev->serialize);
1885                 if (status < 0)
1886                         dev_dbg(&intf->dev, "suspend port %d --> %d\n",
1887                                 port, status);
1888         }
1889
1890         intf->dev.power.power_state = state;
1891         return 0;
1892 }
1893
1894 static int hub_resume(struct usb_interface *intf)
1895 {
1896         struct usb_device       *hdev = interface_to_usbdev(intf);
1897         struct usb_hub          *hub = usb_get_intfdata (intf);
1898         unsigned                port;
1899         int                     status;
1900
1901         if (intf->dev.power.power_state == PM_SUSPEND_ON)
1902                 return 0;
1903
1904         for (port = 0; port < hdev->maxchild; port++) {
1905                 struct usb_device       *udev;
1906                 u16                     portstat, portchange;
1907
1908                 udev = hdev->children [port];
1909                 status = hub_port_status(hdev, port, &portstat, &portchange);
1910                 if (status == 0) {
1911                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
1912                                 clear_port_feature(hdev, port + 1,
1913                                         USB_PORT_FEAT_C_SUSPEND);
1914                                 portchange &= ~USB_PORT_STAT_C_SUSPEND;
1915                         }
1916
1917                         /* let khubd handle disconnects etc */
1918                         if (portchange)
1919                                 continue;
1920                 }
1921
1922                 if (!udev || status < 0)
1923                         continue;
1924                 down (&udev->serialize);
1925                 if (portstat & USB_PORT_STAT_SUSPEND)
1926                         status = hub_port_resume(hdev, port);
1927                 else {
1928                         status = finish_port_resume(udev);
1929                         if (status < 0) {
1930                                 dev_dbg(&intf->dev, "resume port %d --> %d\n",
1931                                         port + 1, status);
1932                                 hub_port_logical_disconnect(hdev, port);
1933                         }
1934                 }
1935                 up(&udev->serialize);
1936         }
1937         intf->dev.power.power_state = PM_SUSPEND_ON;
1938
1939         hub_activate(hub);
1940         return 0;
1941 }
1942
1943 #else   /* !CONFIG_USB_SUSPEND */
1944
1945 int usb_suspend_device(struct usb_device *udev, u32 state)
1946 {
1947         return 0;
1948 }
1949
1950 int usb_resume_device(struct usb_device *udev)
1951 {
1952         return 0;
1953 }
1954
1955 #define hub_suspend             NULL
1956 #define hub_resume              NULL
1957 #define remote_wakeup(x)        0
1958
1959 #endif  /* CONFIG_USB_SUSPEND */
1960
1961 EXPORT_SYMBOL(usb_suspend_device);
1962 EXPORT_SYMBOL(usb_resume_device);
1963
1964
1965
1966 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
1967  *
1968  * Between connect detection and reset signaling there must be a delay
1969  * of 100ms at least for debounce and power-settling.  The corresponding
1970  * timer shall restart whenever the downstream port detects a disconnect.
1971  *
1972  * Apparently there are some bluetooth and irda-dongles and a number of
1973  * low-speed devices for which this debounce period may last over a second.
1974  * Not covered by the spec - but easy to deal with.
1975  *
1976  * This implementation uses a 1500ms total debounce timeout; if the
1977  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
1978  * every 25ms for transient disconnects.  When the port status has been
1979  * unchanged for 100ms it returns the port status.
1980  */
1981
1982 #define HUB_DEBOUNCE_TIMEOUT    1500
1983 #define HUB_DEBOUNCE_STEP         25
1984 #define HUB_DEBOUNCE_STABLE      100
1985
1986 static int hub_port_debounce(struct usb_device *hdev, int port)
1987 {
1988         int ret;
1989         int total_time, stable_time = 0;
1990         u16 portchange, portstatus;
1991         unsigned connection = 0xffff;
1992
1993         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
1994                 ret = hub_port_status(hdev, port, &portstatus, &portchange);
1995                 if (ret < 0)
1996                         return ret;
1997
1998                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
1999                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2000                         stable_time += HUB_DEBOUNCE_STEP;
2001                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2002                                 break;
2003                 } else {
2004                         stable_time = 0;
2005                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2006                 }
2007
2008                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2009                         clear_port_feature(hdev, port+1,
2010                                         USB_PORT_FEAT_C_CONNECTION);
2011                 }
2012
2013                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2014                         break;
2015                 msleep(HUB_DEBOUNCE_STEP);
2016         }
2017
2018         dev_dbg (hubdev (hdev),
2019                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2020                 port + 1, total_time, stable_time, portstatus);
2021
2022         if (stable_time < HUB_DEBOUNCE_STABLE)
2023                 return -ETIMEDOUT;
2024         return portstatus;
2025 }
2026
2027 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2028 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2029
2030 static int hub_set_address(struct usb_device *udev)
2031 {
2032         int retval;
2033
2034         if (udev->devnum == 0)
2035                 return -EINVAL;
2036         if (udev->state == USB_STATE_ADDRESS)
2037                 return 0;
2038         if (udev->state != USB_STATE_DEFAULT)
2039                 return -EINVAL;
2040         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2041                 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2042                 NULL, 0, HZ * USB_CTRL_SET_TIMEOUT);
2043         if (retval == 0) {
2044                 int m = udev->epmaxpacketin[0];
2045
2046                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2047                 usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2048                 usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2049                 udev->epmaxpacketin[0] = udev->epmaxpacketout[0] = m;
2050         }
2051         return retval;
2052 }
2053
2054 /* Reset device, (re)assign address, get device descriptor.
2055  * Device connection must be stable, no more debouncing needed.
2056  * Returns device in USB_STATE_ADDRESS, except on error.
2057  *
2058  * If this is called for an already-existing device (as part of
2059  * usb_reset_device), the caller must own the device lock.  For a
2060  * newly detected device that is not accessible through any global
2061  * pointers, it's not necessary to lock the device.
2062  */
2063 static int
2064 hub_port_init (struct usb_device *hdev, struct usb_device *udev, int port,
2065                 int retry_counter)
2066 {
2067         static DECLARE_MUTEX(usb_address0_sem);
2068
2069         int                     i, j, retval;
2070         unsigned                delay = HUB_SHORT_RESET_TIME;
2071         enum usb_device_speed   oldspeed = udev->speed;
2072
2073         /* root hub ports have a slightly longer reset period
2074          * (from USB 2.0 spec, section 7.1.7.5)
2075          */
2076         if (!hdev->parent) {
2077                 delay = HUB_ROOT_RESET_TIME;
2078                 if (port + 1 == hdev->bus->otg_port)
2079                         hdev->bus->b_hnp_enable = 0;
2080         }
2081
2082         /* Some low speed devices have problems with the quick delay, so */
2083         /*  be a bit pessimistic with those devices. RHbug #23670 */
2084         if (oldspeed == USB_SPEED_LOW)
2085                 delay = HUB_LONG_RESET_TIME;
2086
2087         down(&usb_address0_sem);
2088
2089         /* Reset the device; full speed may morph to high speed */
2090         retval = hub_port_reset(hdev, port, udev, delay);
2091         if (retval < 0)         /* error or disconnect */
2092                 goto fail;
2093                                 /* success, speed is known */
2094         retval = -ENODEV;
2095
2096         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2097                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2098                 goto fail;
2099         }
2100         oldspeed = udev->speed;
2101
2102         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2103          * it's fixed size except for full speed devices.
2104          */
2105         switch (udev->speed) {
2106         case USB_SPEED_HIGH:            /* fixed at 64 */
2107                 i = 64;
2108                 break;
2109         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2110                 /* to determine the ep0 maxpacket size, try to read
2111                  * the device descriptor to get bMaxPacketSize0 and
2112                  * then correct our initial guess.
2113                  */
2114                 i = 64;
2115                 break;
2116         case USB_SPEED_LOW:             /* fixed at 8 */
2117                 i = 8;
2118                 break;
2119         default:
2120                 goto fail;
2121         }
2122         udev->epmaxpacketin[0] = udev->epmaxpacketout[0] = i;
2123
2124         dev_info (&udev->dev,
2125                         "%s %s speed USB device using %s and address %d\n",
2126                         (udev->config) ? "reset" : "new",
2127                         ({ char *speed; switch (udev->speed) {
2128                         case USB_SPEED_LOW:     speed = "low";  break;
2129                         case USB_SPEED_FULL:    speed = "full"; break;
2130                         case USB_SPEED_HIGH:    speed = "high"; break;
2131                         default:                speed = "?";    break;
2132                         }; speed;}),
2133                         udev->bus->controller->driver->name,
2134                         udev->devnum);
2135
2136         /* Set up TT records, if needed  */
2137         if (hdev->tt) {
2138                 udev->tt = hdev->tt;
2139                 udev->ttport = hdev->ttport;
2140         } else if (udev->speed != USB_SPEED_HIGH
2141                         && hdev->speed == USB_SPEED_HIGH) {
2142                 struct usb_hub *hub;
2143
2144                 hub = usb_get_intfdata(hdev->actconfig->interface[0]);
2145                 udev->tt = &hub->tt;
2146                 udev->ttport = port + 1;
2147         }
2148
2149         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2150          * Because device hardware and firmware is sometimes buggy in
2151          * this area, and this is how Linux has done it for ages.
2152          * Change it cautiously.
2153          *
2154          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2155          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2156          * so it may help with some non-standards-compliant devices.
2157          * Otherwise we start with SET_ADDRESS and then try to read the
2158          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2159          * value.
2160          */
2161         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2162                 if (USE_NEW_SCHEME(retry_counter)) {
2163                         struct usb_device_descriptor *buf;
2164
2165 #define GET_DESCRIPTOR_BUFSIZE  64
2166                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2167                         if (!buf) {
2168                                 retval = -ENOMEM;
2169                                 continue;
2170                         }
2171                         buf->bMaxPacketSize0 = 0;
2172
2173                         /* Use a short timeout the first time through,
2174                          * so that recalcitrant full-speed devices with
2175                          * 8- or 16-byte ep0-maxpackets won't slow things
2176                          * down tremendously by NAKing the unexpectedly
2177                          * early status stage.
2178                          */
2179                         j = usb_control_msg(udev, usb_rcvaddr0pipe(),
2180                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2181                                         USB_DT_DEVICE << 8, 0,
2182                                         buf, GET_DESCRIPTOR_BUFSIZE,
2183                                         (i ? HZ * USB_CTRL_GET_TIMEOUT : HZ));
2184                         udev->descriptor.bMaxPacketSize0 =
2185                                         buf->bMaxPacketSize0;
2186                         kfree(buf);
2187
2188                         retval = hub_port_reset(hdev, port, udev, delay);
2189                         if (retval < 0)         /* error or disconnect */
2190                                 goto fail;
2191                         if (oldspeed != udev->speed) {
2192                                 dev_dbg(&udev->dev,
2193                                         "device reset changed speed!\n");
2194                                 retval = -ENODEV;
2195                                 goto fail;
2196                         }
2197                         if (udev->descriptor.bMaxPacketSize0 == 0) {
2198                                 dev_err(&udev->dev, "device descriptor "
2199                                                 "read/%s, error %d\n",
2200                                                 "64", j);
2201                                 retval = -EMSGSIZE;
2202                                 continue;
2203                         }
2204 #undef GET_DESCRIPTOR_BUFSIZE
2205                 }
2206
2207                 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2208                         retval = hub_set_address(udev);
2209                         if (retval >= 0)
2210                                 break;
2211                         msleep(200);
2212                 }
2213                 if (retval < 0) {
2214                         dev_err(&udev->dev,
2215                                 "device not accepting address %d, error %d\n",
2216                                 udev->devnum, retval);
2217                         goto fail;
2218                 }
2219
2220                 /* cope with hardware quirkiness:
2221                  *  - let SET_ADDRESS settle, some device hardware wants it
2222                  *  - read ep0 maxpacket even for high and low speed,
2223                  */
2224                 msleep(10);
2225                 if (USE_NEW_SCHEME(retry_counter))
2226                         break;
2227
2228                 retval = usb_get_device_descriptor(udev, 8);
2229                 if (retval < 8) {
2230                         dev_err(&udev->dev, "device descriptor "
2231                                         "read/%s, error %d\n",
2232                                         "8", retval);
2233                         if (retval >= 0)
2234                                 retval = -EMSGSIZE;
2235                 } else {
2236                         retval = 0;
2237                         break;
2238                 }
2239         }
2240         if (retval)
2241                 goto fail;
2242
2243         /* Should we verify that the value is valid? */
2244         i = udev->descriptor.bMaxPacketSize0;
2245         if (udev->epmaxpacketin[0] != i) {
2246                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2247                 usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2248                 usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2249                 udev->epmaxpacketin[0] = udev->epmaxpacketout[0] = i;
2250         }
2251
2252         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2253         if (retval < (signed)sizeof(udev->descriptor)) {
2254                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2255                         "all", retval);
2256                 if (retval >= 0)
2257                         retval = -ENOMSG;
2258                 goto fail;
2259         }
2260
2261         retval = 0;
2262
2263 fail:
2264         up(&usb_address0_sem);
2265         return retval;
2266 }
2267
2268 static void
2269 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port)
2270 {
2271         struct usb_qualifier_descriptor *qual;
2272         int                             status;
2273
2274         qual = kmalloc (sizeof *qual, SLAB_KERNEL);
2275         if (qual == 0)
2276                 return;
2277
2278         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2279                         qual, sizeof *qual);
2280         if (status == sizeof *qual) {
2281                 dev_info(&udev->dev, "not running at top speed; "
2282                         "connect to a high speed hub\n");
2283                 /* hub LEDs are probably harder to miss than syslog */
2284                 if (hub->has_indicators) {
2285                         hub->indicator[port] = INDICATOR_GREEN_BLINK;
2286                         schedule_work (&hub->leds);
2287                 }
2288         }
2289         kfree (qual);
2290 }
2291
2292 static unsigned
2293 hub_power_remaining (struct usb_hub *hub)
2294 {
2295         struct usb_device *hdev = hub->hdev;
2296         int remaining;
2297         unsigned i;
2298
2299         remaining = hub->power_budget;
2300         if (!remaining)         /* self-powered */
2301                 return 0;
2302
2303         for (i = 0; i < hdev->maxchild; i++) {
2304                 struct usb_device       *udev = hdev->children[i];
2305                 int                     delta, ceiling;
2306
2307                 if (!udev)
2308                         continue;
2309
2310                 /* 100mA per-port ceiling, or 8mA for OTG ports */
2311                 if (i != (udev->bus->otg_port - 1) || hdev->parent)
2312                         ceiling = 50;
2313                 else
2314                         ceiling = 4;
2315
2316                 if (udev->actconfig)
2317                         delta = udev->actconfig->desc.bMaxPower;
2318                 else
2319                         delta = ceiling;
2320                 // dev_dbg(&udev->dev, "budgeted %dmA\n", 2 * delta);
2321                 if (delta > ceiling)
2322                         dev_warn(&udev->dev, "%dmA over %dmA budget!\n",
2323                                 2 * (delta - ceiling), 2 * ceiling);
2324                 remaining -= delta;
2325         }
2326         if (remaining < 0) {
2327                 dev_warn(&hub->intf->dev,
2328                         "%dmA over power budget!\n",
2329                         -2 * remaining);
2330                 remaining = 0;
2331         }
2332         return remaining;
2333 }
2334
2335 /* Handle physical or logical connection change events.
2336  * This routine is called when:
2337  *      a port connection-change occurs;
2338  *      a port enable-change occurs (often caused by EMI);
2339  *      usb_reset_device() encounters changed descriptors (as from
2340  *              a firmware download)
2341  * caller already locked the hub
2342  */
2343 static void hub_port_connect_change(struct usb_hub *hub, int port,
2344                                         u16 portstatus, u16 portchange)
2345 {
2346         struct usb_device *hdev = hub->hdev;
2347         struct device *hub_dev = &hub->intf->dev;
2348         int status, i;
2349
2350         dev_dbg (hub_dev,
2351                 "port %d, status %04x, change %04x, %s\n",
2352                 port + 1, portstatus, portchange, portspeed (portstatus));
2353
2354         if (hub->has_indicators) {
2355                 set_port_led(hdev, port + 1, HUB_LED_AUTO);
2356                 hub->indicator[port] = INDICATOR_AUTO;
2357         }
2358
2359         /* Disconnect any existing devices under this port */
2360         if (hdev->children[port])
2361                 usb_disconnect(&hdev->children[port]);
2362         clear_bit(port, hub->change_bits);
2363
2364 #ifdef  CONFIG_USB_OTG
2365         /* during HNP, don't repeat the debounce */
2366         if (hdev->bus->is_b_host)
2367                 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2368 #endif
2369
2370         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2371                 status = hub_port_debounce(hdev, port);
2372                 if (status < 0) {
2373                         dev_err (hub_dev,
2374                                 "connect-debounce failed, port %d disabled\n",
2375                                 port+1);
2376                         goto done;
2377                 }
2378                 portstatus = status;
2379         }
2380
2381         /* Return now if nothing is connected */
2382         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2383
2384                 /* maybe switch power back on (e.g. root hub was reset) */
2385                 if ((hub->descriptor->wHubCharacteristics
2386                                         & HUB_CHAR_LPSM) < 2
2387                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2388                         set_port_feature(hdev, port + 1, USB_PORT_FEAT_POWER);
2389
2390                 if (portstatus & USB_PORT_STAT_ENABLE)
2391                         goto done;
2392                 return;
2393         }
2394
2395 #ifdef  CONFIG_USB_SUSPEND
2396         /* If something is connected, but the port is suspended, wake it up.. */
2397         if (portstatus & USB_PORT_STAT_SUSPEND) {
2398                 status = hub_port_resume(hdev, port);
2399                 if (status < 0)
2400                         dev_dbg(hub_dev, "can't clear suspend on port %d; %d\n", port+1, status);
2401         }
2402 #endif
2403
2404         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2405                 struct usb_device *udev;
2406
2407                 /* reallocate for each attempt, since references
2408                  * to the previous one can escape in various ways
2409                  */
2410                 udev = usb_alloc_dev(hdev, hdev->bus, port);
2411                 if (!udev) {
2412                         dev_err (hub_dev,
2413                                 "couldn't allocate port %d usb_device\n", port+1);
2414                         goto done;
2415                 }
2416
2417                 usb_set_device_state(udev, USB_STATE_POWERED);
2418                 udev->speed = USB_SPEED_UNKNOWN;
2419
2420                 /* set the address */
2421                 choose_address(udev);
2422                 if (udev->devnum <= 0) {
2423                         status = -ENOTCONN;     /* Don't retry */
2424                         goto loop;
2425                 }
2426
2427                 /* reset and get descriptor */
2428                 status = hub_port_init(hdev, udev, port, i);
2429                 if (status < 0)
2430                         goto loop;
2431
2432                 /* consecutive bus-powered hubs aren't reliable; they can
2433                  * violate the voltage drop budget.  if the new child has
2434                  * a "powered" LED, users should notice we didn't enable it
2435                  * (without reading syslog), even without per-port LEDs
2436                  * on the parent.
2437                  */
2438                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2439                                 && hub->power_budget) {
2440                         u16     devstat;
2441
2442                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2443                                         &devstat);
2444                         if (status < 0) {
2445                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2446                                 goto loop;
2447                         }
2448                         cpu_to_le16s(&devstat);
2449                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2450                                 dev_err(&udev->dev,
2451                                         "can't connect bus-powered hub "
2452                                         "to this port\n");
2453                                 if (hub->has_indicators) {
2454                                         hub->indicator[port] =
2455                                                 INDICATOR_AMBER_BLINK;
2456                                         schedule_work (&hub->leds);
2457                                 }
2458                                 status = -ENOTCONN;     /* Don't retry */
2459                                 goto loop;
2460                         }
2461                 }
2462
2463                 /* check for devices running slower than they could */
2464                 if (udev->descriptor.bcdUSB >= 0x0200
2465                                 && udev->speed == USB_SPEED_FULL
2466                                 && highspeed_hubs != 0)
2467                         check_highspeed (hub, udev, port);
2468
2469                 /* Store the parent's children[] pointer.  At this point
2470                  * udev becomes globally accessible, although presumably
2471                  * no one will look at it until hdev is unlocked.
2472                  */
2473                 down (&udev->serialize);
2474                 status = 0;
2475
2476                 /* We mustn't add new devices if the parent hub has
2477                  * been disconnected; we would race with the
2478                  * recursively_mark_NOTATTACHED() routine.
2479                  */
2480                 spin_lock_irq(&device_state_lock);
2481                 if (hdev->state == USB_STATE_NOTATTACHED)
2482                         status = -ENOTCONN;
2483                 else
2484                         hdev->children[port] = udev;
2485                 spin_unlock_irq(&device_state_lock);
2486
2487                 /* Run it through the hoops (find a driver, etc) */
2488                 if (!status) {
2489                         status = usb_new_device(udev);
2490                         if (status) {
2491                                 spin_lock_irq(&device_state_lock);
2492                                 hdev->children[port] = NULL;
2493                                 spin_unlock_irq(&device_state_lock);
2494                         }
2495                 }
2496
2497                 up (&udev->serialize);
2498                 if (status)
2499                         goto loop;
2500
2501                 status = hub_power_remaining(hub);
2502                 if (status)
2503                         dev_dbg(hub_dev,
2504                                 "%dmA power budget left\n",
2505                                 2 * status);
2506
2507                 return;
2508
2509 loop:
2510                 hub_port_disable(hdev, port);
2511                 usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2512                 usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2513                 release_address(udev);
2514                 usb_put_dev(udev);
2515                 if (status == -ENOTCONN)
2516                         break;
2517         }
2518
2519 done:
2520         hub_port_disable(hdev, port);
2521 }
2522
2523 static void hub_events(void)
2524 {
2525         struct list_head *tmp;
2526         struct usb_device *hdev;
2527         struct usb_hub *hub;
2528         struct device *hub_dev;
2529         u16 hubstatus;
2530         u16 hubchange;
2531         u16 portstatus;
2532         u16 portchange;
2533         int i, ret;
2534         int connect_change;
2535
2536         /*
2537          *  We restart the list every time to avoid a deadlock with
2538          * deleting hubs downstream from this one. This should be
2539          * safe since we delete the hub from the event list.
2540          * Not the most efficient, but avoids deadlocks.
2541          */
2542         while (1) {
2543
2544                 /* Grab the first entry at the beginning of the list */
2545                 spin_lock_irq(&hub_event_lock);
2546                 if (list_empty(&hub_event_list)) {
2547                         spin_unlock_irq(&hub_event_lock);
2548                         break;
2549                 }
2550
2551                 tmp = hub_event_list.next;
2552                 list_del_init(tmp);
2553
2554                 hub = list_entry(tmp, struct usb_hub, event_list);
2555                 hdev = hub->hdev;
2556                 hub_dev = &hub->intf->dev;
2557
2558                 usb_get_dev(hdev);
2559                 spin_unlock_irq(&hub_event_lock);
2560
2561                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
2562                                 hdev->state, hub->descriptor
2563                                         ? hub->descriptor->bNbrPorts
2564                                         : 0,
2565                                 /* NOTE: expects max 15 ports... */
2566                                 (u16) hub->change_bits[0],
2567                                 (u16) hub->event_bits[0]);
2568
2569                 /* Lock the device, then check to see if we were
2570                  * disconnected while waiting for the lock to succeed. */
2571                 if (locktree(hdev) < 0)
2572                         break;
2573                 if (hdev->state != USB_STATE_CONFIGURED ||
2574                                 !hdev->actconfig ||
2575                                 hub != usb_get_intfdata(
2576                                         hdev->actconfig->interface[0]))
2577                         goto loop;
2578
2579                 if (hub->error) {
2580                         dev_dbg (hub_dev, "resetting for error %d\n",
2581                                 hub->error);
2582
2583                         ret = usb_reset_device(hdev);
2584                         if (ret) {
2585                                 dev_dbg (hub_dev,
2586                                         "error resetting hub: %d\n", ret);
2587                                 goto loop;
2588                         }
2589
2590                         hub->nerrors = 0;
2591                         hub->error = 0;
2592                 }
2593
2594                 /* deal with port status changes */
2595                 for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
2596                         connect_change = test_bit(i, hub->change_bits);
2597                         if (!test_and_clear_bit(i+1, hub->event_bits) &&
2598                                         !connect_change)
2599                                 continue;
2600
2601                         ret = hub_port_status(hdev, i,
2602                                         &portstatus, &portchange);
2603                         if (ret < 0)
2604                                 continue;
2605
2606                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2607                                 clear_port_feature(hdev,
2608                                         i + 1, USB_PORT_FEAT_C_CONNECTION);
2609                                 connect_change = 1;
2610                         }
2611
2612                         if (portchange & USB_PORT_STAT_C_ENABLE) {
2613                                 if (!connect_change)
2614                                         dev_dbg (hub_dev,
2615                                                 "port %d enable change, "
2616                                                 "status %08x\n",
2617                                                 i + 1, portstatus);
2618                                 clear_port_feature(hdev,
2619                                         i + 1, USB_PORT_FEAT_C_ENABLE);
2620
2621                                 /*
2622                                  * EM interference sometimes causes badly
2623                                  * shielded USB devices to be shutdown by
2624                                  * the hub, this hack enables them again.
2625                                  * Works at least with mouse driver.
2626                                  */
2627                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
2628                                     && !connect_change
2629                                     && hdev->children[i]) {
2630                                         dev_err (hub_dev,
2631                                             "port %i "
2632                                             "disabled by hub (EMI?), "
2633                                             "re-enabling...\n",
2634                                                 i + 1);
2635                                         connect_change = 1;
2636                                 }
2637                         }
2638
2639                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2640                                 clear_port_feature(hdev, i + 1,
2641                                         USB_PORT_FEAT_C_SUSPEND);
2642                                 if (hdev->children[i]) {
2643                                         ret = remote_wakeup(hdev->children[i]);
2644                                         if (ret < 0)
2645                                                 connect_change = 1;
2646                                 } else {
2647                                         ret = -ENODEV;
2648                                         hub_port_disable(hdev, i);
2649                                 }
2650                                 dev_dbg (hub_dev,
2651                                         "resume on port %d, status %d\n",
2652                                         i + 1, ret);
2653                         }
2654
2655                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2656                                 dev_err (hub_dev,
2657                                         "over-current change on port %d\n",
2658                                         i + 1);
2659                                 clear_port_feature(hdev,
2660                                         i + 1, USB_PORT_FEAT_C_OVER_CURRENT);
2661                                 hub_power_on(hub);
2662                         }
2663
2664                         if (portchange & USB_PORT_STAT_C_RESET) {
2665                                 dev_dbg (hub_dev,
2666                                         "reset change on port %d\n",
2667                                         i + 1);
2668                                 clear_port_feature(hdev,
2669                                         i + 1, USB_PORT_FEAT_C_RESET);
2670                         }
2671
2672                         if (connect_change)
2673                                 hub_port_connect_change(hub, i,
2674                                                 portstatus, portchange);
2675                 } /* end for i */
2676
2677                 /* deal with hub status changes */
2678                 if (test_and_clear_bit(0, hub->event_bits) == 0)
2679                         ;       /* do nothing */
2680                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2681                         dev_err (hub_dev, "get_hub_status failed\n");
2682                 else {
2683                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2684                                 dev_dbg (hub_dev, "power change\n");
2685                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2686                         }
2687                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
2688                                 dev_dbg (hub_dev, "overcurrent change\n");
2689                                 msleep(500);    /* Cool down */
2690                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2691                                 hub_power_on(hub);
2692                         }
2693                 }
2694
2695 loop:
2696                 usb_unlock_device(hdev);
2697                 usb_put_dev(hdev);
2698
2699         } /* end while (1) */
2700 }
2701
2702 static int hub_thread(void *__unused)
2703 {
2704         /*
2705          * This thread doesn't need any user-level access,
2706          * so get rid of all our resources
2707          */
2708
2709         daemonize("khubd");
2710         allow_signal(SIGKILL);
2711
2712         /* Send me a signal to get me die (for debugging) */
2713         do {
2714                 hub_events();
2715                 wait_event_interruptible(khubd_wait, !list_empty(&hub_event_list));
2716                 if (current->flags & PF_FREEZE)
2717                         refrigerator(PF_FREEZE);
2718         } while (!signal_pending(current));
2719
2720         pr_debug ("%s: khubd exiting\n", usbcore_name);
2721         complete_and_exit(&khubd_exited, 0);
2722 }
2723
2724 static struct usb_device_id hub_id_table [] = {
2725     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2726       .bDeviceClass = USB_CLASS_HUB},
2727     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2728       .bInterfaceClass = USB_CLASS_HUB},
2729     { }                                         /* Terminating entry */
2730 };
2731
2732 MODULE_DEVICE_TABLE (usb, hub_id_table);
2733
2734 static struct usb_driver hub_driver = {
2735         .owner =        THIS_MODULE,
2736         .name =         "hub",
2737         .probe =        hub_probe,
2738         .disconnect =   hub_disconnect,
2739         .suspend =      hub_suspend,
2740         .resume =       hub_resume,
2741         .ioctl =        hub_ioctl,
2742         .id_table =     hub_id_table,
2743 };
2744
2745 int usb_hub_init(void)
2746 {
2747         pid_t pid;
2748
2749         if (usb_register(&hub_driver) < 0) {
2750                 printk(KERN_ERR "%s: can't register hub driver\n",
2751                         usbcore_name);
2752                 return -1;
2753         }
2754
2755         pid = kernel_thread(hub_thread, NULL, CLONE_KERNEL);
2756         if (pid >= 0) {
2757                 khubd_pid = pid;
2758
2759                 return 0;
2760         }
2761
2762         /* Fall through if kernel_thread failed */
2763         usb_deregister(&hub_driver);
2764         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2765
2766         return -1;
2767 }
2768
2769 void usb_hub_cleanup(void)
2770 {
2771         int ret;
2772
2773         /* Kill the thread */
2774         ret = kill_proc(khubd_pid, SIGKILL, 1);
2775
2776         wait_for_completion(&khubd_exited);
2777
2778         /*
2779          * Hub resources are freed for us by usb_deregister. It calls
2780          * usb_driver_purge on every device which in turn calls that
2781          * devices disconnect function if it is using this driver.
2782          * The hub_disconnect function takes care of releasing the
2783          * individual hub resources. -greg
2784          */
2785         usb_deregister(&hub_driver);
2786 } /* usb_hub_cleanup() */
2787
2788
2789 static int config_descriptors_changed(struct usb_device *udev)
2790 {
2791         unsigned                        index;
2792         unsigned                        len = 0;
2793         struct usb_config_descriptor    *buf;
2794
2795         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2796                 if (len < udev->config[index].desc.wTotalLength)
2797                         len = udev->config[index].desc.wTotalLength;
2798         }
2799         buf = kmalloc (len, SLAB_KERNEL);
2800         if (buf == 0) {
2801                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2802                 /* assume the worst */
2803                 return 1;
2804         }
2805         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2806                 int length;
2807                 int old_length = udev->config[index].desc.wTotalLength;
2808
2809                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2810                                 old_length);
2811                 if (length < old_length) {
2812                         dev_dbg(&udev->dev, "config index %d, error %d\n",
2813                                         index, length);
2814                         break;
2815                 }
2816                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2817                                 != 0) {
2818                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2819                                 index, buf->bConfigurationValue);
2820                         break;
2821                 }
2822         }
2823         kfree(buf);
2824         return index != udev->descriptor.bNumConfigurations;
2825 }
2826
2827 /**
2828  * usb_reset_device - perform a USB port reset to reinitialize a device
2829  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2830  *
2831  * WARNING - don't reset any device unless drivers for all of its
2832  * interfaces are expecting that reset!  Maybe some driver->reset()
2833  * method should eventually help ensure sufficient cooperation.
2834  *
2835  * Do a port reset, reassign the device's address, and establish its
2836  * former operating configuration.  If the reset fails, or the device's
2837  * descriptors change from their values before the reset, or the original
2838  * configuration and altsettings cannot be restored, a flag will be set
2839  * telling khubd to pretend the device has been disconnected and then
2840  * re-connected.  All drivers will be unbound, and the device will be
2841  * re-enumerated and probed all over again.
2842  *
2843  * Returns 0 if the reset succeeded, -ENODEV if the device has been
2844  * flagged for logical disconnection, or some other negative error code
2845  * if the reset wasn't even attempted.
2846  *
2847  * The caller must own the device lock.  For example, it's safe to use
2848  * this from a driver probe() routine after downloading new firmware.
2849  * For calls that might not occur during probe(), drivers should lock
2850  * the device using usb_lock_device_for_reset().
2851  */
2852 int usb_reset_device(struct usb_device *udev)
2853 {
2854         struct usb_device *parent = udev->parent;
2855         struct usb_device_descriptor descriptor = udev->descriptor;
2856         int i, ret = 0, port = -1;
2857         int udev_is_a_hub = 0;
2858
2859         if (udev->state == USB_STATE_NOTATTACHED ||
2860                         udev->state == USB_STATE_SUSPENDED) {
2861                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2862                                 udev->state);
2863                 return -EINVAL;
2864         }
2865
2866         if (!parent) {
2867                 /* this requires hcd-specific logic; see OHCI hc_restart() */
2868                 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2869                 return -EISDIR;
2870         }
2871
2872         for (i = 0; i < parent->maxchild; i++)
2873                 if (parent->children[i] == udev) {
2874                         port = i;
2875                         break;
2876                 }
2877
2878         if (port < 0) {
2879                 /* If this ever happens, it's very bad */
2880                 dev_err(&udev->dev, "Can't locate device's port!\n");
2881                 return -ENOENT;
2882         }
2883
2884         /* If we're resetting an active hub, take some special actions */
2885         if (udev->actconfig &&
2886                         udev->actconfig->interface[0]->dev.driver ==
2887                         &hub_driver.driver) {
2888                 udev_is_a_hub = 1;
2889                 hub_pre_reset(udev);
2890         }
2891
2892         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
2893
2894                 /* ep0 maxpacket size may change; let the HCD know about it.
2895                  * Other endpoints will be handled by re-enumeration. */
2896                 usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2897                 usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2898                 ret = hub_port_init(parent, udev, port, i);
2899                 if (ret >= 0)
2900                         break;
2901         }
2902         if (ret < 0)
2903                 goto re_enumerate;
2904
2905         /* Device might have changed firmware (DFU or similar) */
2906         if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
2907                         || config_descriptors_changed (udev)) {
2908                 dev_info(&udev->dev, "device firmware changed\n");
2909                 udev->descriptor = descriptor;  /* for disconnect() calls */
2910                 goto re_enumerate;
2911         }
2912
2913         if (!udev->actconfig)
2914                 goto done;
2915
2916         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2917                         USB_REQ_SET_CONFIGURATION, 0,
2918                         udev->actconfig->desc.bConfigurationValue, 0,
2919                         NULL, 0, HZ * USB_CTRL_SET_TIMEOUT);
2920         if (ret < 0) {
2921                 dev_err(&udev->dev,
2922                         "can't restore configuration #%d (error=%d)\n",
2923                         udev->actconfig->desc.bConfigurationValue, ret);
2924                 goto re_enumerate;
2925         }
2926         usb_set_device_state(udev, USB_STATE_CONFIGURED);
2927
2928         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
2929                 struct usb_interface *intf = udev->actconfig->interface[i];
2930                 struct usb_interface_descriptor *desc;
2931
2932                 /* set_interface resets host side toggle even
2933                  * for altsetting zero.  the interface may have no driver.
2934                  */
2935                 desc = &intf->cur_altsetting->desc;
2936                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
2937                         desc->bAlternateSetting);
2938                 if (ret < 0) {
2939                         dev_err(&udev->dev, "failed to restore interface %d "
2940                                 "altsetting %d (error=%d)\n",
2941                                 desc->bInterfaceNumber,
2942                                 desc->bAlternateSetting,
2943                                 ret);
2944                         goto re_enumerate;
2945                 }
2946         }
2947
2948 done:
2949         if (udev_is_a_hub)
2950                 hub_post_reset(udev);
2951         return 0;
2952
2953 re_enumerate:
2954         hub_port_logical_disconnect(parent, port);
2955         return -ENODEV;
2956 }