drivers/usb/core/hub.c

   1 /*
   2  * USB hub driver.
   3  *
   4  * (C) Copyright 1999 Linus Torvalds
   5  * (C) Copyright 1999 Johannes Erdfelt
   6  * (C) Copyright 1999 Gregory P. Smith
   7  * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
   8  *
   9  */
  10
  11 #include <linux/config.h>
  12 #ifdef CONFIG_USB_DEBUG
  13         #define DEBUG
  14 #else
  15         #undef DEBUG
  16 #endif
  17 #include <linux/kernel.h>
  18 #include <linux/errno.h>
  19 #include <linux/module.h>
  20 #include <linux/moduleparam.h>
  21 #include <linux/completion.h>
  22 #include <linux/sched.h>
  23 #include <linux/list.h>
  24 #include <linux/slab.h>
  25 #include <linux/smp_lock.h>
  26 #include <linux/ioctl.h>
  27 #include <linux/usb.h>
  28 #include <linux/usbdevice_fs.h>
  29 #include <linux/kthread.h>
  30
  31 #include <asm/semaphore.h>
  32 #include <asm/uaccess.h>
  33 #include <asm/byteorder.h>
  34
  35 #include "usb.h"
  36 #include "hcd.h"
  37 #include "hub.h"
  38
  39 /* Protect struct usb_device->state and ->children members
  40  * Note: Both are also protected by ->serialize, except that ->state can
  41  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
  42 static DEFINE_SPINLOCK(device_state_lock);
  43
  44 /* khubd's worklist and its lock */
  45 static DEFINE_SPINLOCK(hub_event_lock);
  46 static LIST_HEAD(hub_event_list);       /* List of hubs needing servicing */
  47
  48 /* Wakes up khubd */
  49 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
  50
  51 static struct task_struct *khubd_task;
  52
  53 /* cycle leds on hubs that aren't blinking for attention */
  54 static int blinkenlights = 0;
  55 module_param (blinkenlights, bool, S_IRUGO);
  56 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
  57
  58 /*
  59  * As of 2.6.10 we introduce a new USB device initialization scheme which
  60  * closely resembles the way Windows works.  Hopefully it will be compatible
  61  * with a wider range of devices than the old scheme.  However some previously
  62  * working devices may start giving rise to "device not accepting address"
  63  * errors; if that happens the user can try the old scheme by adjusting the
  64  * following module parameters.
  65  *
  66  * For maximum flexibility there are two boolean parameters to control the
  67  * hub driver's behavior.  On the first initialization attempt, if the
  68  * "old_scheme_first" parameter is set then the old scheme will be used,
  69  * otherwise the new scheme is used.  If that fails and "use_both_schemes"
  70  * is set, then the driver will make another attempt, using the other scheme.
  71  */
  72 static int old_scheme_first = 0;
  73 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
  74 MODULE_PARM_DESC(old_scheme_first,
  75                  "start with the old device initialization scheme");
  76
  77 static int use_both_schemes = 1;
  78 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
  79 MODULE_PARM_DESC(use_both_schemes,
  80                 "try the other device initialization scheme if the "
  81                 "first one fails");
  82
  83
  84 #ifdef  DEBUG
  85 static inline char *portspeed (int portstatus)
  86 {
  87         if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
  88                 return "480 Mb/s";
  89         else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
  90                 return "1.5 Mb/s";
  91         else
  92                 return "12 Mb/s";
  93 }
  94 #endif
  95
  96 /* Note that hdev or one of its children must be locked! */
  97 static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
  98 {
  99         return usb_get_intfdata(hdev->actconfig->interface[0]);
 100 }
 101
 102 /* USB 2.0 spec Section 11.24.4.5 */
 103 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
 104 {
 105         int i, ret;
 106
 107         for (i = 0; i < 3; i++) {
 108                 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 109                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
 110                         USB_DT_HUB << 8, 0, data, size,
 111                         USB_CTRL_GET_TIMEOUT);
 112                 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
 113                         return ret;
 114         }
 115         return -EINVAL;
 116 }
 117
 118 /*
 119  * USB 2.0 spec Section 11.24.2.1
 120  */
 121 static int clear_hub_feature(struct usb_device *hdev, int feature)
 122 {
 123         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 124                 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
 125 }
 126
 127 /*
 128  * USB 2.0 spec Section 11.24.2.2
 129  */
 130 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
 131 {
 132         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 133                 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
 134                 NULL, 0, 1000);
 135 }
 136
 137 /*
 138  * USB 2.0 spec Section 11.24.2.13
 139  */
 140 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
 141 {
 142         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 143                 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
 144                 NULL, 0, 1000);
 145 }
 146
 147 /*
 148  * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
 149  * for info about using port indicators
 150  */
 151 static void set_port_led(
 152         struct usb_hub *hub,
 153         int port1,
 154         int selector
 155 )
 156 {
 157         int status = set_port_feature(hub->hdev, (selector << 8) | port1,
 158                         USB_PORT_FEAT_INDICATOR);
 159         if (status < 0)
 160                 dev_dbg (hub->intfdev,
 161                         "port %d indicator %s status %d\n",
 162                         port1,
 163                         ({ char *s; switch (selector) {
 164                         case HUB_LED_AMBER: s = "amber"; break;
 165                         case HUB_LED_GREEN: s = "green"; break;
 166                         case HUB_LED_OFF: s = "off"; break;
 167                         case HUB_LED_AUTO: s = "auto"; break;
 168                         default: s = "??"; break;
 169                         }; s; }),
 170                         status);
 171 }
 172
 173 #define LED_CYCLE_PERIOD        ((2*HZ)/3)
 174
 175 static void led_work (void *__hub)
 176 {
 177         struct usb_hub          *hub = __hub;
 178         struct usb_device       *hdev = hub->hdev;
 179         unsigned                i;
 180         unsigned                changed = 0;
 181         int                     cursor = -1;
 182
 183         if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
 184                 return;
 185
 186         for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
 187                 unsigned        selector, mode;
 188
 189                 /* 30%-50% duty cycle */
 190
 191                 switch (hub->indicator[i]) {
 192                 /* cycle marker */
 193                 case INDICATOR_CYCLE:
 194                         cursor = i;
 195                         selector = HUB_LED_AUTO;
 196                         mode = INDICATOR_AUTO;
 197                         break;
 198                 /* blinking green = sw attention */
 199                 case INDICATOR_GREEN_BLINK:
 200                         selector = HUB_LED_GREEN;
 201                         mode = INDICATOR_GREEN_BLINK_OFF;
 202                         break;
 203                 case INDICATOR_GREEN_BLINK_OFF:
 204                         selector = HUB_LED_OFF;
 205                         mode = INDICATOR_GREEN_BLINK;
 206                         break;
 207                 /* blinking amber = hw attention */
 208                 case INDICATOR_AMBER_BLINK:
 209                         selector = HUB_LED_AMBER;
 210                         mode = INDICATOR_AMBER_BLINK_OFF;
 211                         break;
 212                 case INDICATOR_AMBER_BLINK_OFF:
 213                         selector = HUB_LED_OFF;
 214                         mode = INDICATOR_AMBER_BLINK;
 215                         break;
 216                 /* blink green/amber = reserved */
 217                 case INDICATOR_ALT_BLINK:
 218                         selector = HUB_LED_GREEN;
 219                         mode = INDICATOR_ALT_BLINK_OFF;
 220                         break;
 221                 case INDICATOR_ALT_BLINK_OFF:
 222                         selector = HUB_LED_AMBER;
 223                         mode = INDICATOR_ALT_BLINK;
 224                         break;
 225                 default:
 226                         continue;
 227                 }
 228                 if (selector != HUB_LED_AUTO)
 229                         changed = 1;
 230                 set_port_led(hub, i + 1, selector);
 231                 hub->indicator[i] = mode;
 232         }
 233         if (!changed && blinkenlights) {
 234                 cursor++;
 235                 cursor %= hub->descriptor->bNbrPorts;
 236                 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
 237                 hub->indicator[cursor] = INDICATOR_CYCLE;
 238                 changed++;
 239         }
 240         if (changed)
 241                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 242 }
 243
 244 /* use a short timeout for hub/port status fetches */
 245 #define USB_STS_TIMEOUT         1000
 246 #define USB_STS_RETRIES         5
 247
 248 /*
 249  * USB 2.0 spec Section 11.24.2.6
 250  */
 251 static int get_hub_status(struct usb_device *hdev,
 252                 struct usb_hub_status *data)
 253 {
 254         int i, status = -ETIMEDOUT;
 255
 256         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
 257                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 258                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
 259                         data, sizeof(*data), USB_STS_TIMEOUT);
 260         }
 261         return status;
 262 }
 263
 264 /*
 265  * USB 2.0 spec Section 11.24.2.7
 266  */
 267 static int get_port_status(struct usb_device *hdev, int port1,
 268                 struct usb_port_status *data)
 269 {
 270         int i, status = -ETIMEDOUT;
 271
 272         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
 273                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 274                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
 275                         data, sizeof(*data), USB_STS_TIMEOUT);
 276         }
 277         return status;
 278 }
 279
 280 static void kick_khubd(struct usb_hub *hub)
 281 {
 282         unsigned long   flags;
 283
 284         spin_lock_irqsave(&hub_event_lock, flags);
 285         if (list_empty(&hub->event_list)) {
 286                 list_add_tail(&hub->event_list, &hub_event_list);
 287                 wake_up(&khubd_wait);
 288         }
 289         spin_unlock_irqrestore(&hub_event_lock, flags);
 290 }
 291
 292 void usb_kick_khubd(struct usb_device *hdev)
 293 {
 294         kick_khubd(hdev_to_hub(hdev));
 295 }
 296
 297
 298 /* completion function, fires on port status changes and various faults */
 299 static void hub_irq(struct urb *urb, struct pt_regs *regs)
 300 {
 301         struct usb_hub *hub = (struct usb_hub *)urb->context;
 302         int status;
 303         int i;
 304         unsigned long bits;
 305
 306         switch (urb->status) {
 307         case -ENOENT:           /* synchronous unlink */
 308         case -ECONNRESET:       /* async unlink */
 309         case -ESHUTDOWN:        /* hardware going away */
 310                 return;
 311
 312         default:                /* presumably an error */
 313                 /* Cause a hub reset after 10 consecutive errors */
 314                 dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
 315                 if ((++hub->nerrors < 10) || hub->error)
 316                         goto resubmit;
 317                 hub->error = urb->status;
 318                 /* FALL THROUGH */
 319
 320         /* let khubd handle things */
 321         case 0:                 /* we got data:  port status changed */
 322                 bits = 0;
 323                 for (i = 0; i < urb->actual_length; ++i)
 324                         bits |= ((unsigned long) ((*hub->buffer)[i]))
 325                                         << (i*8);
 326                 hub->event_bits[0] = bits;
 327                 break;
 328         }
 329
 330         hub->nerrors = 0;
 331
 332         /* Something happened, let khubd figure it out */
 333         kick_khubd(hub);
 334
 335 resubmit:
 336         if (hub->quiescing)
 337                 return;
 338
 339         if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
 340                         && status != -ENODEV && status != -EPERM)
 341                 dev_err (hub->intfdev, "resubmit --> %d\n", status);
 342 }
 343
 344 /* USB 2.0 spec Section 11.24.2.3 */
 345 static inline int
 346 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
 347 {
 348         return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 349                                HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
 350                                tt, NULL, 0, 1000);
 351 }
 352
 353 /*
 354  * enumeration blocks khubd for a long time. we use keventd instead, since
 355  * long blocking there is the exception, not the rule.  accordingly, HCDs
 356  * talking to TTs must queue control transfers (not just bulk and iso), so
 357  * both can talk to the same hub concurrently.
 358  */
 359 static void hub_tt_kevent (void *arg)
 360 {
 361         struct usb_hub          *hub = arg;
 362         unsigned long           flags;
 363
 364         spin_lock_irqsave (&hub->tt.lock, flags);
 365         while (!list_empty (&hub->tt.clear_list)) {
 366                 struct list_head        *temp;
 367                 struct usb_tt_clear     *clear;
 368                 struct usb_device       *hdev = hub->hdev;
 369                 int                     status;
 370
 371                 temp = hub->tt.clear_list.next;
 372                 clear = list_entry (temp, struct usb_tt_clear, clear_list);
 373                 list_del (&clear->clear_list);
 374
 375                 /* drop lock so HCD can concurrently report other TT errors */
 376                 spin_unlock_irqrestore (&hub->tt.lock, flags);
 377                 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
 378                 spin_lock_irqsave (&hub->tt.lock, flags);
 379
 380                 if (status)
 381                         dev_err (&hdev->dev,
 382                                 "clear tt %d (%04x) error %d\n",
 383                                 clear->tt, clear->devinfo, status);
 384                 kfree(clear);
 385         }
 386         spin_unlock_irqrestore (&hub->tt.lock, flags);
 387 }
 388
 389 /**
 390  * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
 391  * @udev: the device whose split transaction failed
 392  * @pipe: identifies the endpoint of the failed transaction
 393  *
 394  * High speed HCDs use this to tell the hub driver that some split control or
 395  * bulk transaction failed in a way that requires clearing internal state of
 396  * a transaction translator.  This is normally detected (and reported) from
 397  * interrupt context.
 398  *
 399  * It may not be possible for that hub to handle additional full (or low)
 400  * speed transactions until that state is fully cleared out.
 401  */
 402 void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
 403 {
 404         struct usb_tt           *tt = udev->tt;
 405         unsigned long           flags;
 406         struct usb_tt_clear     *clear;
 407
 408         /* we've got to cope with an arbitrary number of pending TT clears,
 409          * since each TT has "at least two" buffers that can need it (and
 410          * there can be many TTs per hub).  even if they're uncommon.
 411          */
 412         if ((clear = kmalloc (sizeof *clear, SLAB_ATOMIC)) == NULL) {
 413                 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
 414                 /* FIXME recover somehow ... RESET_TT? */
 415                 return;
 416         }
 417
 418         /* info that CLEAR_TT_BUFFER needs */
 419         clear->tt = tt->multi ? udev->ttport : 1;
 420         clear->devinfo = usb_pipeendpoint (pipe);
 421         clear->devinfo |= udev->devnum << 4;
 422         clear->devinfo |= usb_pipecontrol (pipe)
 423                         ? (USB_ENDPOINT_XFER_CONTROL << 11)
 424                         : (USB_ENDPOINT_XFER_BULK << 11);
 425         if (usb_pipein (pipe))
 426                 clear->devinfo |= 1 << 15;
 427
 428         /* tell keventd to clear state for this TT */
 429         spin_lock_irqsave (&tt->lock, flags);
 430         list_add_tail (&clear->clear_list, &tt->clear_list);
 431         schedule_work (&tt->kevent);
 432         spin_unlock_irqrestore (&tt->lock, flags);
 433 }
 434
 435 static void hub_power_on(struct usb_hub *hub)
 436 {
 437         int port1;
 438
 439         /* if hub supports power switching, enable power on each port */
 440         if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_LPSM) < 2) {
 441                 dev_dbg(hub->intfdev, "enabling power on all ports\n");
 442                 for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
 443                         set_port_feature(hub->hdev, port1,
 444                                         USB_PORT_FEAT_POWER);
 445         }
 446
 447         /* Wait for power to be enabled */
 448         msleep(hub->descriptor->bPwrOn2PwrGood * 2);
 449 }
 450
 451 static void hub_quiesce(struct usb_hub *hub)
 452 {
 453         /* stop khubd and related activity */
 454         hub->quiescing = 1;
 455         usb_kill_urb(hub->urb);
 456         if (hub->has_indicators)
 457                 cancel_delayed_work(&hub->leds);
 458         if (hub->has_indicators || hub->tt.hub)
 459                 flush_scheduled_work();
 460 }
 461
 462 static void hub_activate(struct usb_hub *hub)
 463 {
 464         int     status;
 465
 466         hub->quiescing = 0;
 467         hub->activating = 1;
 468         status = usb_submit_urb(hub->urb, GFP_NOIO);
 469         if (status < 0)
 470                 dev_err(hub->intfdev, "activate --> %d\n", status);
 471         if (hub->has_indicators && blinkenlights)
 472                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 473
 474         /* scan all ports ASAP */
 475         kick_khubd(hub);
 476 }
 477
 478 static int hub_hub_status(struct usb_hub *hub,
 479                 u16 *status, u16 *change)
 480 {
 481         int ret;
 482
 483         ret = get_hub_status(hub->hdev, &hub->status->hub);
 484         if (ret < 0)
 485                 dev_err (hub->intfdev,
 486                         "%s failed (err = %d)\n", __FUNCTION__, ret);
 487         else {
 488                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
 489                 *change = le16_to_cpu(hub->status->hub.wHubChange);
 490                 ret = 0;
 491         }
 492         return ret;
 493 }
 494
 495 static int hub_configure(struct usb_hub *hub,
 496         struct usb_endpoint_descriptor *endpoint)
 497 {
 498         struct usb_device *hdev = hub->hdev;
 499         struct device *hub_dev = hub->intfdev;
 500         u16 hubstatus, hubchange;
 501         unsigned int pipe;
 502         int maxp, ret;
 503         char *message;
 504
 505         hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
 506                         &hub->buffer_dma);
 507         if (!hub->buffer) {
 508                 message = "can't allocate hub irq buffer";
 509                 ret = -ENOMEM;
 510                 goto fail;
 511         }
 512
 513         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
 514         if (!hub->status) {
 515                 message = "can't kmalloc hub status buffer";
 516                 ret = -ENOMEM;
 517                 goto fail;
 518         }
 519
 520         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
 521         if (!hub->descriptor) {
 522                 message = "can't kmalloc hub descriptor";
 523                 ret = -ENOMEM;
 524                 goto fail;
 525         }
 526
 527         /* Request the entire hub descriptor.
 528          * hub->descriptor can handle USB_MAXCHILDREN ports,
 529          * but the hub can/will return fewer bytes here.
 530          */
 531         ret = get_hub_descriptor(hdev, hub->descriptor,
 532                         sizeof(*hub->descriptor));
 533         if (ret < 0) {
 534                 message = "can't read hub descriptor";
 535                 goto fail;
 536         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
 537                 message = "hub has too many ports!";
 538                 ret = -ENODEV;
 539                 goto fail;
 540         }
 541
 542         hdev->maxchild = hub->descriptor->bNbrPorts;
 543         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
 544                 (hdev->maxchild == 1) ? "" : "s");
 545
 546         le16_to_cpus(&hub->descriptor->wHubCharacteristics);
 547
 548         if (hub->descriptor->wHubCharacteristics & HUB_CHAR_COMPOUND) {
 549                 int     i;
 550                 char    portstr [USB_MAXCHILDREN + 1];
 551
 552                 for (i = 0; i < hdev->maxchild; i++)
 553                         portstr[i] = hub->descriptor->DeviceRemovable
 554                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
 555                                 ? 'F' : 'R';
 556                 portstr[hdev->maxchild] = 0;
 557                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
 558         } else
 559                 dev_dbg(hub_dev, "standalone hub\n");
 560
 561         switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_LPSM) {
 562                 case 0x00:
 563                         dev_dbg(hub_dev, "ganged power switching\n");
 564                         break;
 565                 case 0x01:
 566                         dev_dbg(hub_dev, "individual port power switching\n");
 567                         break;
 568                 case 0x02:
 569                 case 0x03:
 570                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
 571                         break;
 572         }
 573
 574         switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) {
 575                 case 0x00:
 576                         dev_dbg(hub_dev, "global over-current protection\n");
 577                         break;
 578                 case 0x08:
 579                         dev_dbg(hub_dev, "individual port over-current protection\n");
 580                         break;
 581                 case 0x10:
 582                 case 0x18:
 583                         dev_dbg(hub_dev, "no over-current protection\n");
 584                         break;
 585         }
 586
 587         spin_lock_init (&hub->tt.lock);
 588         INIT_LIST_HEAD (&hub->tt.clear_list);
 589         INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub);
 590         switch (hdev->descriptor.bDeviceProtocol) {
 591                 case 0:
 592                         break;
 593                 case 1:
 594                         dev_dbg(hub_dev, "Single TT\n");
 595                         hub->tt.hub = hdev;
 596                         break;
 597                 case 2:
 598                         ret = usb_set_interface(hdev, 0, 1);
 599                         if (ret == 0) {
 600                                 dev_dbg(hub_dev, "TT per port\n");
 601                                 hub->tt.multi = 1;
 602                         } else
 603                                 dev_err(hub_dev, "Using single TT (err %d)\n",
 604                                         ret);
 605                         hub->tt.hub = hdev;
 606                         break;
 607                 default:
 608                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
 609                                 hdev->descriptor.bDeviceProtocol);
 610                         break;
 611         }
 612
 613         switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_TTTT) {
 614                 case 0x00:
 615                         if (hdev->descriptor.bDeviceProtocol != 0)
 616                                 dev_dbg(hub_dev, "TT requires at most 8 FS bit times\n");
 617                         break;
 618                 case 0x20:
 619                         dev_dbg(hub_dev, "TT requires at most 16 FS bit times\n");
 620                         break;
 621                 case 0x40:
 622                         dev_dbg(hub_dev, "TT requires at most 24 FS bit times\n");
 623                         break;
 624                 case 0x60:
 625                         dev_dbg(hub_dev, "TT requires at most 32 FS bit times\n");
 626                         break;
 627         }
 628
 629         /* probe() zeroes hub->indicator[] */
 630         if (hub->descriptor->wHubCharacteristics & HUB_CHAR_PORTIND) {
 631                 hub->has_indicators = 1;
 632                 dev_dbg(hub_dev, "Port indicators are supported\n");
 633         }
 634
 635         dev_dbg(hub_dev, "power on to power good time: %dms\n",
 636                 hub->descriptor->bPwrOn2PwrGood * 2);
 637
 638         /* power budgeting mostly matters with bus-powered hubs,
 639          * and battery-powered root hubs (may provide just 8 mA).
 640          */
 641         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
 642         if (ret < 0) {
 643                 message = "can't get hub status";
 644                 goto fail;
 645         }
 646         le16_to_cpus(&hubstatus);
 647         if (hdev == hdev->bus->root_hub) {
 648                 struct usb_hcd *hcd =
 649                                 container_of(hdev->bus, struct usb_hcd, self);
 650
 651                 hub->power_budget = min(500u, hcd->power_budget) / 2;
 652         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
 653                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
 654                         hub->descriptor->bHubContrCurrent);
 655                 hub->power_budget = (501 - hub->descriptor->bHubContrCurrent)
 656                                         / 2;
 657         }
 658         if (hub->power_budget)
 659                 dev_dbg(hub_dev, "%dmA bus power budget for children\n",
 660                         hub->power_budget * 2);
 661
 662
 663         ret = hub_hub_status(hub, &hubstatus, &hubchange);
 664         if (ret < 0) {
 665                 message = "can't get hub status";
 666                 goto fail;
 667         }
 668
 669         /* local power status reports aren't always correct */
 670         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
 671                 dev_dbg(hub_dev, "local power source is %s\n",
 672                         (hubstatus & HUB_STATUS_LOCAL_POWER)
 673                         ? "lost (inactive)" : "good");
 674
 675         if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) == 0)
 676                 dev_dbg(hub_dev, "%sover-current condition exists\n",
 677                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
 678
 679         /* set up the interrupt endpoint */
 680         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
 681         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
 682
 683         if (maxp > sizeof(*hub->buffer))
 684                 maxp = sizeof(*hub->buffer);
 685
 686         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
 687         if (!hub->urb) {
 688                 message = "couldn't allocate interrupt urb";
 689                 ret = -ENOMEM;
 690                 goto fail;
 691         }
 692
 693         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
 694                 hub, endpoint->bInterval);
 695         hub->urb->transfer_dma = hub->buffer_dma;
 696         hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 697
 698         /* maybe cycle the hub leds */
 699         if (hub->has_indicators && blinkenlights)
 700                 hub->indicator [0] = INDICATOR_CYCLE;
 701
 702         hub_power_on(hub);
 703         hub_activate(hub);
 704         return 0;
 705
 706 fail:
 707         dev_err (hub_dev, "config failed, %s (err %d)\n",
 708                         message, ret);
 709         /* hub_disconnect() frees urb and descriptor */
 710         return ret;
 711 }
 712
 713 static unsigned highspeed_hubs;
 714
 715 static void hub_disconnect(struct usb_interface *intf)
 716 {
 717         struct usb_hub *hub = usb_get_intfdata (intf);
 718         struct usb_device *hdev;
 719
 720         if (!hub)
 721                 return;
 722         hdev = hub->hdev;
 723
 724         if (hdev->speed == USB_SPEED_HIGH)
 725                 highspeed_hubs--;
 726
 727         usb_set_intfdata (intf, NULL);
 728
 729         hub_quiesce(hub);
 730         usb_free_urb(hub->urb);
 731         hub->urb = NULL;
 732
 733         spin_lock_irq(&hub_event_lock);
 734         list_del_init(&hub->event_list);
 735         spin_unlock_irq(&hub_event_lock);
 736
 737         kfree(hub->descriptor);
 738         hub->descriptor = NULL;
 739
 740         kfree(hub->status);
 741         hub->status = NULL;
 742
 743         if (hub->buffer) {
 744                 usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
 745                                 hub->buffer_dma);
 746                 hub->buffer = NULL;
 747         }
 748
 749         /* Free the memory */
 750         kfree(hub);
 751 }
 752
 753 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
 754 {
 755         struct usb_host_interface *desc;
 756         struct usb_endpoint_descriptor *endpoint;
 757         struct usb_device *hdev;
 758         struct usb_hub *hub;
 759
 760         desc = intf->cur_altsetting;
 761         hdev = interface_to_usbdev(intf);
 762
 763         /* Some hubs have a subclass of 1, which AFAICT according to the */
 764         /*  specs is not defined, but it works */
 765         if ((desc->desc.bInterfaceSubClass != 0) &&
 766             (desc->desc.bInterfaceSubClass != 1)) {
 767 descriptor_error:
 768                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
 769                 return -EIO;
 770         }
 771
 772         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
 773         if (desc->desc.bNumEndpoints != 1)
 774                 goto descriptor_error;
 775
 776         endpoint = &desc->endpoint[0].desc;
 777
 778         /* Output endpoint? Curiouser and curiouser.. */
 779         if (!(endpoint->bEndpointAddress & USB_DIR_IN))
 780                 goto descriptor_error;
 781
 782         /* If it's not an interrupt endpoint, we'd better punt! */
 783         if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
 784                         != USB_ENDPOINT_XFER_INT)
 785                 goto descriptor_error;
 786
 787         /* We found a hub */
 788         dev_info (&intf->dev, "USB hub found\n");
 789
 790         hub = kmalloc(sizeof(*hub), GFP_KERNEL);
 791         if (!hub) {
 792                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
 793                 return -ENOMEM;
 794         }
 795
 796         memset(hub, 0, sizeof(*hub));
 797
 798         INIT_LIST_HEAD(&hub->event_list);
 799         hub->intfdev = &intf->dev;
 800         hub->hdev = hdev;
 801         INIT_WORK(&hub->leds, led_work, hub);
 802
 803         usb_set_intfdata (intf, hub);
 804
 805         if (hdev->speed == USB_SPEED_HIGH)
 806                 highspeed_hubs++;
 807
 808         if (hub_configure(hub, endpoint) >= 0)
 809                 return 0;
 810
 811         hub_disconnect (intf);
 812         return -ENODEV;
 813 }
 814
 815 static int
 816 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
 817 {
 818         struct usb_device *hdev = interface_to_usbdev (intf);
 819
 820         /* assert ifno == 0 (part of hub spec) */
 821         switch (code) {
 822         case USBDEVFS_HUB_PORTINFO: {
 823                 struct usbdevfs_hub_portinfo *info = user_data;
 824                 int i;
 825
 826                 spin_lock_irq(&device_state_lock);
 827                 if (hdev->devnum <= 0)
 828                         info->nports = 0;
 829                 else {
 830                         info->nports = hdev->maxchild;
 831                         for (i = 0; i < info->nports; i++) {
 832                                 if (hdev->children[i] == NULL)
 833                                         info->port[i] = 0;
 834                                 else
 835                                         info->port[i] =
 836                                                 hdev->children[i]->devnum;
 837                         }
 838                 }
 839                 spin_unlock_irq(&device_state_lock);
 840
 841                 return info->nports + 1;
 842                 }
 843
 844         default:
 845                 return -ENOSYS;
 846         }
 847 }
 848
 849 /* caller has locked the hub device */
 850 static void hub_pre_reset(struct usb_hub *hub)
 851 {
 852         struct usb_device *hdev = hub->hdev;
 853         int i;
 854
 855         for (i = 0; i < hdev->maxchild; ++i) {
 856                 if (hdev->children[i])
 857                         usb_disconnect(&hdev->children[i]);
 858         }
 859         hub_quiesce(hub);
 860 }
 861
 862 /* caller has locked the hub device */
 863 static void hub_post_reset(struct usb_hub *hub)
 864 {
 865         hub_activate(hub);
 866         hub_power_on(hub);
 867 }
 868
 869
 870 /* grab device/port lock, returning index of that port (zero based).
 871  * protects the upstream link used by this device from concurrent
 872  * tree operations like suspend, resume, reset, and disconnect, which
 873  * apply to everything downstream of a given port.
 874  */
 875 static int locktree(struct usb_device *udev)
 876 {
 877         int                     t;
 878         struct usb_device       *hdev;
 879
 880         if (!udev)
 881                 return -ENODEV;
 882
 883         /* root hub is always the first lock in the series */
 884         hdev = udev->parent;
 885         if (!hdev) {
 886                 usb_lock_device(udev);
 887                 return 0;
 888         }
 889
 890         /* on the path from root to us, lock everything from
 891          * top down, dropping parent locks when not needed
 892          */
 893         t = locktree(hdev);
 894         if (t < 0)
 895                 return t;
 896         for (t = 0; t < hdev->maxchild; t++) {
 897                 if (hdev->children[t] == udev) {
 898                         /* everything is fail-fast once disconnect
 899                          * processing starts
 900                          */
 901                         if (udev->state == USB_STATE_NOTATTACHED)
 902                                 break;
 903
 904                         /* when everyone grabs locks top->bottom,
 905                          * non-overlapping work may be concurrent
 906                          */
 907                         down(&udev->serialize);
 908                         up(&hdev->serialize);
 909                         return t + 1;
 910                 }
 911         }
 912         usb_unlock_device(hdev);
 913         return -ENODEV;
 914 }
 915
 916 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
 917 {
 918         int i;
 919
 920         for (i = 0; i < udev->maxchild; ++i) {
 921                 if (udev->children[i])
 922                         recursively_mark_NOTATTACHED(udev->children[i]);
 923         }
 924         udev->state = USB_STATE_NOTATTACHED;
 925 }
 926
 927 /**
 928  * usb_set_device_state - change a device's current state (usbcore, hcds)
 929  * @udev: pointer to device whose state should be changed
 930  * @new_state: new state value to be stored
 931  *
 932  * udev->state is _not_ fully protected by the device lock.  Although
 933  * most transitions are made only while holding the lock, the state can
 934  * can change to USB_STATE_NOTATTACHED at almost any time.  This
 935  * is so that devices can be marked as disconnected as soon as possible,
 936  * without having to wait for any semaphores to be released.  As a result,
 937  * all changes to any device's state must be protected by the
 938  * device_state_lock spinlock.
 939  *
 940  * Once a device has been added to the device tree, all changes to its state
 941  * should be made using this routine.  The state should _not_ be set directly.
 942  *
 943  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
 944  * Otherwise udev->state is set to new_state, and if new_state is
 945  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
 946  * to USB_STATE_NOTATTACHED.
 947  */
 948 void usb_set_device_state(struct usb_device *udev,
 949                 enum usb_device_state new_state)
 950 {
 951         unsigned long flags;
 952
 953         spin_lock_irqsave(&device_state_lock, flags);
 954         if (udev->state == USB_STATE_NOTATTACHED)
 955                 ;       /* do nothing */
 956         else if (new_state != USB_STATE_NOTATTACHED)
 957                 udev->state = new_state;
 958         else
 959                 recursively_mark_NOTATTACHED(udev);
 960         spin_unlock_irqrestore(&device_state_lock, flags);
 961 }
 962 EXPORT_SYMBOL(usb_set_device_state);
 963
 964
 965 static void choose_address(struct usb_device *udev)
 966 {
 967         int             devnum;
 968         struct usb_bus  *bus = udev->bus;
 969
 970         /* If khubd ever becomes multithreaded, this will need a lock */
 971
 972         /* Try to allocate the next devnum beginning at bus->devnum_next. */
 973         devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
 974                         bus->devnum_next);
 975         if (devnum >= 128)
 976                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
 977
 978         bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
 979
 980         if (devnum < 128) {
 981                 set_bit(devnum, bus->devmap.devicemap);
 982                 udev->devnum = devnum;
 983         }
 984 }
 985
 986 static void release_address(struct usb_device *udev)
 987 {
 988         if (udev->devnum > 0) {
 989                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
 990                 udev->devnum = -1;
 991         }
 992 }
 993
 994 /**
 995  * usb_disconnect - disconnect a device (usbcore-internal)
 996  * @pdev: pointer to device being disconnected
 997  * Context: !in_interrupt ()
 998  *
 999  * Something got disconnected. Get rid of it and all of its children.
1000  *
1001  * If *pdev is a normal device then the parent hub must already be locked.
1002  * If *pdev is a root hub then this routine will acquire the
1003  * usb_bus_list_lock on behalf of the caller.
1004  *
1005  * Only hub drivers (including virtual root hub drivers for host
1006  * controllers) should ever call this.
1007  *
1008  * This call is synchronous, and may not be used in an interrupt context.
1009  */
1010 void usb_disconnect(struct usb_device **pdev)
1011 {
1012         struct usb_device       *udev = *pdev;
1013         int                     i;
1014
1015         if (!udev) {
1016                 pr_debug ("%s nodev\n", __FUNCTION__);
1017                 return;
1018         }
1019
1020         /* mark the device as inactive, so any further urb submissions for
1021          * this device (and any of its children) will fail immediately.
1022          * this quiesces everyting except pending urbs.
1023          */
1024         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1025
1026         /* lock the bus list on behalf of HCDs unregistering their root hubs */
1027         if (!udev->parent) {
1028                 down(&usb_bus_list_lock);
1029                 usb_lock_device(udev);
1030         } else
1031                 down(&udev->serialize);
1032
1033         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1034
1035         /* Free up all the children before we remove this device */
1036         for (i = 0; i < USB_MAXCHILDREN; i++) {
1037                 if (udev->children[i])
1038                         usb_disconnect(&udev->children[i]);
1039         }
1040
1041         /* deallocate hcd/hardware state ... nuking all pending urbs and
1042          * cleaning up all state associated with the current configuration
1043          * so that the hardware is now fully quiesced.
1044          */
1045         usb_disable_device(udev, 0);
1046
1047         /* Free the device number, remove the /proc/bus/usb entry and
1048          * the sysfs attributes, and delete the parent's children[]
1049          * (or root_hub) pointer.
1050          */
1051         dev_dbg (&udev->dev, "unregistering device\n");
1052         release_address(udev);
1053         usbfs_remove_device(udev);
1054         usbdev_remove(udev);
1055         usb_remove_sysfs_dev_files(udev);
1056
1057         /* Avoid races with recursively_mark_NOTATTACHED() */
1058         spin_lock_irq(&device_state_lock);
1059         *pdev = NULL;
1060         spin_unlock_irq(&device_state_lock);
1061
1062         if (!udev->parent) {
1063                 usb_unlock_device(udev);
1064                 up(&usb_bus_list_lock);
1065         } else
1066                 up(&udev->serialize);
1067
1068         device_unregister(&udev->dev);
1069 }
1070
1071 static int choose_configuration(struct usb_device *udev)
1072 {
1073         int c, i;
1074
1075         /* NOTE: this should interact with hub power budgeting */
1076
1077         c = udev->config[0].desc.bConfigurationValue;
1078         if (udev->descriptor.bNumConfigurations != 1) {
1079                 for (i = 0; i < udev->descriptor.bNumConfigurations; i++) {
1080                         struct usb_interface_descriptor *desc;
1081
1082                         /* heuristic:  Linux is more likely to have class
1083                          * drivers, so avoid vendor-specific interfaces.
1084                          */
1085                         desc = &udev->config[i].intf_cache[0]
1086                                         ->altsetting->desc;
1087                         if (desc->bInterfaceClass == USB_CLASS_VENDOR_SPEC)
1088                                 continue;
1089                         /* COMM/2/all is CDC ACM, except 0xff is MSFT RNDIS.
1090                          * MSFT needs this to be the first config; never use
1091                          * it as the default unless Linux has host-side RNDIS.
1092                          * A second config would ideally be CDC-Ethernet, but
1093                          * may instead be the "vendor specific" CDC subset
1094                          * long used by ARM Linux for sa1100 or pxa255.
1095                          */
1096                         if (desc->bInterfaceClass == USB_CLASS_COMM
1097                                         && desc->bInterfaceSubClass == 2
1098                                         && desc->bInterfaceProtocol == 0xff) {
1099                                 c = udev->config[1].desc.bConfigurationValue;
1100                                 continue;
1101                         }
1102                         c = udev->config[i].desc.bConfigurationValue;
1103                         break;
1104                 }
1105                 dev_info(&udev->dev,
1106                         "configuration #%d chosen from %d choices\n",
1107                         c, udev->descriptor.bNumConfigurations);
1108         }
1109         return c;
1110 }
1111
1112 #ifdef DEBUG
1113 static void show_string(struct usb_device *udev, char *id, char *string)
1114 {
1115         if (!string)
1116                 return;
1117         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1118 }
1119
1120 #else
1121 static inline void show_string(struct usb_device *udev, char *id, char *string)
1122 {}
1123 #endif
1124
1125 static void get_string(struct usb_device *udev, char **string, int index)
1126 {
1127         char *buf;
1128
1129         if (!index)
1130                 return;
1131         buf = kmalloc(256, GFP_KERNEL);
1132         if (!buf)
1133                 return;
1134         if (usb_string(udev, index, buf, 256) > 0)
1135                 *string = buf;
1136         else
1137                 kfree(buf);
1138 }
1139
1140
1141 #ifdef  CONFIG_USB_OTG
1142 #include "otg_whitelist.h"
1143 #endif
1144
1145 /**
1146  * usb_new_device - perform initial device setup (usbcore-internal)
1147  * @udev: newly addressed device (in ADDRESS state)
1148  *
1149  * This is called with devices which have been enumerated, but not yet
1150  * configured.  The device descriptor is available, but not descriptors
1151  * for any device configuration.  The caller must have locked udev and
1152  * either the parent hub (if udev is a normal device) or else the
1153  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1154  * udev has already been installed, but udev is not yet visible through
1155  * sysfs or other filesystem code.
1156  *
1157  * Returns 0 for success (device is configured and listed, with its
1158  * interfaces, in sysfs); else a negative errno value.
1159  *
1160  * This call is synchronous, and may not be used in an interrupt context.
1161  *
1162  * Only the hub driver should ever call this; root hub registration
1163  * uses it indirectly.
1164  */
1165 int usb_new_device(struct usb_device *udev)
1166 {
1167         int err;
1168         int c;
1169
1170         err = usb_get_configuration(udev);
1171         if (err < 0) {
1172                 dev_err(&udev->dev, "can't read configurations, error %d\n",
1173                         err);
1174                 goto fail;
1175         }
1176
1177         /* read the standard strings and cache them if present */
1178         get_string(udev, &udev->product, udev->descriptor.iProduct);
1179         get_string(udev, &udev->manufacturer, udev->descriptor.iManufacturer);
1180         get_string(udev, &udev->serial, udev->descriptor.iSerialNumber);
1181
1182         /* Tell the world! */
1183         dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1184                         "SerialNumber=%d\n",
1185                         udev->descriptor.iManufacturer,
1186                         udev->descriptor.iProduct,
1187                         udev->descriptor.iSerialNumber);
1188         show_string(udev, "Product", udev->product);
1189         show_string(udev, "Manufacturer", udev->manufacturer);
1190         show_string(udev, "SerialNumber", udev->serial);
1191
1192 #ifdef  CONFIG_USB_OTG
1193         /*
1194          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1195          * to wake us after we've powered off VBUS; and HNP, switching roles
1196          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1197          */
1198         if (!udev->bus->is_b_host
1199                         && udev->config
1200                         && udev->parent == udev->bus->root_hub) {
1201                 struct usb_otg_descriptor       *desc = 0;
1202                 struct usb_bus                  *bus = udev->bus;
1203
1204                 /* descriptor may appear anywhere in config */
1205                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1206                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1207                                         USB_DT_OTG, (void **) &desc) == 0) {
1208                         if (desc->bmAttributes & USB_OTG_HNP) {
1209                                 unsigned                port1;
1210                                 struct usb_device       *root = udev->parent;
1211
1212                                 for (port1 = 1; port1 <= root->maxchild;
1213                                                 port1++) {
1214                                         if (root->children[port1-1] == udev)
1215                                                 break;
1216                                 }
1217
1218                                 dev_info(&udev->dev,
1219                                         "Dual-Role OTG device on %sHNP port\n",
1220                                         (port1 == bus->otg_port)
1221                                                 ? "" : "non-");
1222
1223                                 /* enable HNP before suspend, it's simpler */
1224                                 if (port1 == bus->otg_port)
1225                                         bus->b_hnp_enable = 1;
1226                                 err = usb_control_msg(udev,
1227                                         usb_sndctrlpipe(udev, 0),
1228                                         USB_REQ_SET_FEATURE, 0,
1229                                         bus->b_hnp_enable
1230                                                 ? USB_DEVICE_B_HNP_ENABLE
1231                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1232                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1233                                 if (err < 0) {
1234                                         /* OTG MESSAGE: report errors here,
1235                                          * customize to match your product.
1236                                          */
1237                                         dev_info(&udev->dev,
1238                                                 "can't set HNP mode; %d\n",
1239                                                 err);
1240                                         bus->b_hnp_enable = 0;
1241                                 }
1242                         }
1243                 }
1244         }
1245
1246         if (!is_targeted(udev)) {
1247
1248                 /* Maybe it can talk to us, though we can't talk to it.
1249                  * (Includes HNP test device.)
1250                  */
1251                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1252                         static int __usb_suspend_device (struct usb_device *,
1253                                                 int port1, pm_message_t state);
1254                         err = __usb_suspend_device(udev,
1255                                         udev->bus->otg_port,
1256                                         PMSG_SUSPEND);
1257                         if (err < 0)
1258                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1259                 }
1260                 err = -ENODEV;
1261                 goto fail;
1262         }
1263 #endif
1264
1265         /* put device-specific files into sysfs */
1266         err = device_add (&udev->dev);
1267         if (err) {
1268                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1269                 goto fail;
1270         }
1271         usb_create_sysfs_dev_files (udev);
1272
1273         /* choose and set the configuration. that registers the interfaces
1274          * with the driver core, and lets usb device drivers bind to them.
1275          */
1276         c = choose_configuration(udev);
1277         if (c < 0)
1278                 dev_warn(&udev->dev,
1279                                 "can't choose an initial configuration\n");
1280         else {
1281                 err = usb_set_configuration(udev, c);
1282                 if (err) {
1283                         dev_err(&udev->dev, "can't set config #%d, error %d\n",
1284                                         c, err);
1285                         usb_remove_sysfs_dev_files(udev);
1286                         device_del(&udev->dev);
1287                         goto fail;
1288                 }
1289         }
1290
1291         /* USB device state == configured ... usable */
1292
1293         /* add a /proc/bus/usb entry */
1294         usbdev_add(udev);
1295         usbfs_add_device(udev);
1296         return 0;
1297
1298 fail:
1299         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1300         return err;
1301 }
1302
1303
1304 static int hub_port_status(struct usb_hub *hub, int port1,
1305                                u16 *status, u16 *change)
1306 {
1307         int ret;
1308
1309         ret = get_port_status(hub->hdev, port1, &hub->status->port);
1310         if (ret < 0)
1311                 dev_err (hub->intfdev,
1312                         "%s failed (err = %d)\n", __FUNCTION__, ret);
1313         else {
1314                 *status = le16_to_cpu(hub->status->port.wPortStatus);
1315                 *change = le16_to_cpu(hub->status->port.wPortChange);
1316                 ret = 0;
1317         }
1318         return ret;
1319 }
1320
1321 #define PORT_RESET_TRIES        5
1322 #define SET_ADDRESS_TRIES       2
1323 #define GET_DESCRIPTOR_TRIES    2
1324 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1325 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1326
1327 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1328 #define HUB_SHORT_RESET_TIME    10
1329 #define HUB_LONG_RESET_TIME     200
1330 #define HUB_RESET_TIMEOUT       500
1331
1332 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1333                                 struct usb_device *udev, unsigned int delay)
1334 {
1335         int delay_time, ret;
1336         u16 portstatus;
1337         u16 portchange;
1338
1339         for (delay_time = 0;
1340                         delay_time < HUB_RESET_TIMEOUT;
1341                         delay_time += delay) {
1342                 /* wait to give the device a chance to reset */
1343                 msleep(delay);
1344
1345                 /* read and decode port status */
1346                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1347                 if (ret < 0)
1348                         return ret;
1349
1350                 /* Device went away? */
1351                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1352                         return -ENOTCONN;
1353
1354                 /* bomb out completely if something weird happened */
1355                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1356                         return -EINVAL;
1357
1358                 /* if we`ve finished resetting, then break out of the loop */
1359                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1360                     (portstatus & USB_PORT_STAT_ENABLE)) {
1361                         if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1362                                 udev->speed = USB_SPEED_HIGH;
1363                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1364                                 udev->speed = USB_SPEED_LOW;
1365                         else
1366                                 udev->speed = USB_SPEED_FULL;
1367                         return 0;
1368                 }
1369
1370                 /* switch to the long delay after two short delay failures */
1371                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1372                         delay = HUB_LONG_RESET_TIME;
1373
1374                 dev_dbg (hub->intfdev,
1375                         "port %d not reset yet, waiting %dms\n",
1376                         port1, delay);
1377         }
1378
1379         return -EBUSY;
1380 }
1381
1382 static int hub_port_reset(struct usb_hub *hub, int port1,
1383                                 struct usb_device *udev, unsigned int delay)
1384 {
1385         int i, status;
1386
1387         /* Reset the port */
1388         for (i = 0; i < PORT_RESET_TRIES; i++) {
1389                 status = set_port_feature(hub->hdev,
1390                                 port1, USB_PORT_FEAT_RESET);
1391                 if (status)
1392                         dev_err(hub->intfdev,
1393                                         "cannot reset port %d (err = %d)\n",
1394                                         port1, status);
1395                 else {
1396                         status = hub_port_wait_reset(hub, port1, udev, delay);
1397                         if (status)
1398                                 dev_dbg(hub->intfdev,
1399                                                 "port_wait_reset: err = %d\n",
1400                                                 status);
1401                 }
1402
1403                 /* return on disconnect or reset */
1404                 switch (status) {
1405                 case 0:
1406                         /* TRSTRCY = 10 ms */
1407                         msleep(10);
1408                         /* FALL THROUGH */
1409                 case -ENOTCONN:
1410                 case -ENODEV:
1411                         clear_port_feature(hub->hdev,
1412                                 port1, USB_PORT_FEAT_C_RESET);
1413                         /* FIXME need disconnect() for NOTATTACHED device */
1414                         usb_set_device_state(udev, status
1415                                         ? USB_STATE_NOTATTACHED
1416                                         : USB_STATE_DEFAULT);
1417                         return status;
1418                 }
1419
1420                 dev_dbg (hub->intfdev,
1421                         "port %d not enabled, trying reset again...\n",
1422                         port1);
1423                 delay = HUB_LONG_RESET_TIME;
1424         }
1425
1426         dev_err (hub->intfdev,
1427                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1428                 port1);
1429
1430         return status;
1431 }
1432
1433 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
1434 {
1435         struct usb_device *hdev = hub->hdev;
1436         int ret;
1437
1438         if (hdev->children[port1-1] && set_state) {
1439                 usb_set_device_state(hdev->children[port1-1],
1440                                 USB_STATE_NOTATTACHED);
1441         }
1442         ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
1443         if (ret)
1444                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
1445                         port1, ret);
1446
1447         return ret;
1448 }
1449
1450 /*
1451  * Disable a port and mark a logical connnect-change event, so that some
1452  * time later khubd will disconnect() any existing usb_device on the port
1453  * and will re-enumerate if there actually is a device attached.
1454  */
1455 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1456 {
1457         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1458         hub_port_disable(hub, port1, 1);
1459
1460         /* FIXME let caller ask to power down the port:
1461          *  - some devices won't enumerate without a VBUS power cycle
1462          *  - SRP saves power that way
1463          *  - usb_suspend_device(dev, PMSG_SUSPEND)
1464          * That's easy if this hub can switch power per-port, and
1465          * khubd reactivates the port later (timer, SRP, etc).
1466          * Powerdown must be optional, because of reset/DFU.
1467          */
1468
1469         set_bit(port1, hub->change_bits);
1470         kick_khubd(hub);
1471 }
1472
1473
1474 #ifdef  CONFIG_USB_SUSPEND
1475
1476 /*
1477  * Selective port suspend reduces power; most suspended devices draw
1478  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1479  * All devices below the suspended port are also suspended.
1480  *
1481  * Devices leave suspend state when the host wakes them up.  Some devices
1482  * also support "remote wakeup", where the device can activate the USB
1483  * tree above them to deliver data, such as a keypress or packet.  In
1484  * some cases, this wakes the USB host.
1485  */
1486 static int hub_port_suspend(struct usb_hub *hub, int port1,
1487                 struct usb_device *udev)
1488 {
1489         int     status;
1490
1491         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1492
1493         /* enable remote wakeup when appropriate; this lets the device
1494          * wake up the upstream hub (including maybe the root hub).
1495          *
1496          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1497          * we don't explicitly enable it here.
1498          */
1499         if (udev->actconfig
1500                         // && FIXME (remote wakeup enabled on this bus)
1501                         // ... currently assuming it's always appropriate
1502                         && (udev->actconfig->desc.bmAttributes
1503                                 & USB_CONFIG_ATT_WAKEUP) != 0) {
1504                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1505                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1506                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1507                                 NULL, 0,
1508                                 USB_CTRL_SET_TIMEOUT);
1509                 if (status)
1510                         dev_dbg(&udev->dev,
1511                                 "won't remote wakeup, status %d\n",
1512                                 status);
1513         }
1514
1515         /* see 7.1.7.6 */
1516         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1517         if (status) {
1518                 dev_dbg(hub->intfdev,
1519                         "can't suspend port %d, status %d\n",
1520                         port1, status);
1521                 /* paranoia:  "should not happen" */
1522                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1523                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1524                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1525                                 NULL, 0,
1526                                 USB_CTRL_SET_TIMEOUT);
1527         } else {
1528                 /* device has up to 10 msec to fully suspend */
1529                 dev_dbg(&udev->dev, "usb suspend\n");
1530                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1531                 msleep(10);
1532         }
1533         return status;
1534 }
1535
1536 /*
1537  * Devices on USB hub ports have only one "suspend" state, corresponding
1538  * to ACPI D2, "may cause the device to lose some context".
1539  * State transitions include:
1540  *
1541  *   - suspend, resume ... when the VBUS power link stays live
1542  *   - suspend, disconnect ... VBUS lost
1543  *
1544  * Once VBUS drop breaks the circuit, the port it's using has to go through
1545  * normal re-enumeration procedures, starting with enabling VBUS power.
1546  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1547  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1548  * timer, no SRP, no requests through sysfs.
1549  */
1550 static int __usb_suspend_device (struct usb_device *udev, int port1,
1551                                  pm_message_t state)
1552 {
1553         int     status;
1554
1555         /* caller owns the udev device lock */
1556         if (port1 < 0)
1557                 return port1;
1558
1559         if (udev->state == USB_STATE_SUSPENDED
1560                         || udev->state == USB_STATE_NOTATTACHED) {
1561                 return 0;
1562         }
1563
1564         /* suspend interface drivers; if this is a hub, it
1565          * suspends the child devices
1566          */
1567         if (udev->actconfig) {
1568                 int     i;
1569
1570                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1571                         struct usb_interface    *intf;
1572                         struct usb_driver       *driver;
1573
1574                         intf = udev->actconfig->interface[i];
1575                         if (state.event <= intf->dev.power.power_state.event)
1576                                 continue;
1577                         if (!intf->dev.driver)
1578                                 continue;
1579                         driver = to_usb_driver(intf->dev.driver);
1580
1581                         if (driver->suspend) {
1582                                 status = driver->suspend(intf, state);
1583                                 if (intf->dev.power.power_state.event != state.event
1584                                                 || status)
1585                                         dev_err(&intf->dev,
1586                                                 "suspend %d fail, code %d\n",
1587                                                 state.event, status);
1588                         }
1589
1590                         /* only drivers with suspend() can ever resume();
1591                          * and after power loss, even they won't.
1592                          * bus_rescan_devices() can rebind drivers later.
1593                          *
1594                          * FIXME the PM core self-deadlocks when unbinding
1595                          * drivers during suspend/resume ... everything grabs
1596                          * dpm_sem (not a spinlock, ugh).  we want to unbind,
1597                          * since we know every driver's probe/disconnect works
1598                          * even for drivers that can't suspend.
1599                          */
1600                         if (!driver->suspend || state.event > PM_EVENT_FREEZE) {
1601 #if 1
1602                                 dev_warn(&intf->dev, "resume is unsafe!\n");
1603 #else
1604                                 down_write(&usb_bus_type.rwsem);
1605                                 device_release_driver(&intf->dev);
1606                                 up_write(&usb_bus_type.rwsem);
1607 #endif
1608                         }
1609                 }
1610         }
1611
1612         /*
1613          * FIXME this needs port power off call paths too, to help force
1614          * USB into the "generic" PM model.  At least for devices on
1615          * ports that aren't using ganged switching (usually root hubs).
1616          *
1617          * NOTE: SRP-capable links should adopt more aggressive poweroff
1618          * policies (when HNP doesn't apply) once we have mechanisms to
1619          * turn power back on!  (Likely not before 2.7...)
1620          */
1621         if (state.event > PM_EVENT_FREEZE) {
1622                 dev_warn(&udev->dev, "no poweroff yet, suspending instead\n");
1623         }
1624
1625         /* "global suspend" of the HC-to-USB interface (root hub), or
1626          * "selective suspend" of just one hub-device link.
1627          */
1628         if (!udev->parent) {
1629                 struct usb_bus  *bus = udev->bus;
1630                 if (bus && bus->op->hub_suspend) {
1631                         status = bus->op->hub_suspend (bus);
1632                         if (status == 0) {
1633                                 dev_dbg(&udev->dev, "usb suspend\n");
1634                                 usb_set_device_state(udev,
1635                                                 USB_STATE_SUSPENDED);
1636                         }
1637                 } else
1638                         status = -EOPNOTSUPP;
1639         } else
1640                 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1641                                 udev);
1642
1643         if (status == 0)
1644                 udev->dev.power.power_state = state;
1645         return status;
1646 }
1647
1648 /**
1649  * usb_suspend_device - suspend a usb device
1650  * @udev: device that's no longer in active use
1651  * @state: PMSG_SUSPEND to suspend
1652  * Context: must be able to sleep; device not locked
1653  *
1654  * Suspends a USB device that isn't in active use, conserving power.
1655  * Devices may wake out of a suspend, if anything important happens,
1656  * using the remote wakeup mechanism.  They may also be taken out of
1657  * suspend by the host, using usb_resume_device().  It's also routine
1658  * to disconnect devices while they are suspended.
1659  *
1660  * Suspending OTG devices may trigger HNP, if that's been enabled
1661  * between a pair of dual-role devices.  That will change roles, such
1662  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1663  *
1664  * Returns 0 on success, else negative errno.
1665  */
1666 int usb_suspend_device(struct usb_device *udev, pm_message_t state)
1667 {
1668         int     port1, status;
1669
1670         port1 = locktree(udev);
1671         if (port1 < 0)
1672                 return port1;
1673
1674         status = __usb_suspend_device(udev, port1, state);
1675         usb_unlock_device(udev);
1676         return status;
1677 }
1678
1679 /*
1680  * hardware resume signaling is finished, either because of selective
1681  * resume (by host) or remote wakeup (by device) ... now see what changed
1682  * in the tree that's rooted at this device.
1683  */
1684 static int finish_port_resume(struct usb_device *udev)
1685 {
1686         int     status;
1687         u16     devstatus;
1688
1689         /* caller owns the udev device lock */
1690         dev_dbg(&udev->dev, "usb resume\n");
1691
1692         /* usb ch9 identifies four variants of SUSPENDED, based on what
1693          * state the device resumes to.  Linux currently won't see the
1694          * first two on the host side; they'd be inside hub_port_init()
1695          * during many timeouts, but khubd can't suspend until later.
1696          */
1697         usb_set_device_state(udev, udev->actconfig
1698                         ? USB_STATE_CONFIGURED
1699                         : USB_STATE_ADDRESS);
1700         udev->dev.power.power_state = PMSG_ON;
1701
1702         /* 10.5.4.5 says be sure devices in the tree are still there.
1703          * For now let's assume the device didn't go crazy on resume,
1704          * and device drivers will know about any resume quirks.
1705          */
1706         status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1707         if (status < 0)
1708                 dev_dbg(&udev->dev,
1709                         "gone after usb resume? status %d\n",
1710                         status);
1711         else if (udev->actconfig) {
1712                 unsigned        i;
1713
1714                 le16_to_cpus(&devstatus);
1715                 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
1716                         status = usb_control_msg(udev,
1717                                         usb_sndctrlpipe(udev, 0),
1718                                         USB_REQ_CLEAR_FEATURE,
1719                                                 USB_RECIP_DEVICE,
1720                                         USB_DEVICE_REMOTE_WAKEUP, 0,
1721                                         NULL, 0,
1722                                         USB_CTRL_SET_TIMEOUT);
1723                         if (status) {
1724                                 dev_dbg(&udev->dev, "disable remote "
1725                                         "wakeup, status %d\n", status);
1726                                 status = 0;
1727                         }
1728                 }
1729
1730                 /* resume interface drivers; if this is a hub, it
1731                  * resumes the child devices
1732                  */
1733                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1734                         struct usb_interface    *intf;
1735                         struct usb_driver       *driver;
1736
1737                         intf = udev->actconfig->interface[i];
1738                         if (intf->dev.power.power_state.event == PM_EVENT_ON)
1739                                 continue;
1740                         if (!intf->dev.driver) {
1741                                 /* FIXME maybe force to alt 0 */
1742                                 continue;
1743                         }
1744                         driver = to_usb_driver(intf->dev.driver);
1745
1746                         /* bus_rescan_devices() may rebind drivers */
1747                         if (!driver->resume)
1748                                 continue;
1749
1750                         /* can we do better than just logging errors? */
1751                         status = driver->resume(intf);
1752                         if (intf->dev.power.power_state.event != PM_EVENT_ON
1753                                         || status)
1754                                 dev_dbg(&intf->dev,
1755                                         "resume fail, state %d code %d\n",
1756                                         intf->dev.power.power_state.event, status);
1757                 }
1758                 status = 0;
1759
1760         } else if (udev->devnum <= 0) {
1761                 dev_dbg(&udev->dev, "bogus resume!\n");
1762                 status = -EINVAL;
1763         }
1764         return status;
1765 }
1766
1767 static int
1768 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1769 {
1770         int     status;
1771
1772         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1773
1774         /* see 7.1.7.7; affects power usage, but not budgeting */
1775         status = clear_port_feature(hub->hdev,
1776                         port1, USB_PORT_FEAT_SUSPEND);
1777         if (status) {
1778                 dev_dbg(hub->intfdev,
1779                         "can't resume port %d, status %d\n",
1780                         port1, status);
1781         } else {
1782                 u16             devstatus;
1783                 u16             portchange;
1784
1785                 /* drive resume for at least 20 msec */
1786                 if (udev)
1787                         dev_dbg(&udev->dev, "RESUME\n");
1788                 msleep(25);
1789
1790 #define LIVE_FLAGS      ( USB_PORT_STAT_POWER \
1791                         | USB_PORT_STAT_ENABLE \
1792                         | USB_PORT_STAT_CONNECTION)
1793
1794                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1795                  * stop resume signaling.  Then finish the resume
1796                  * sequence.
1797                  */
1798                 devstatus = portchange = 0;
1799                 status = hub_port_status(hub, port1,
1800                                 &devstatus, &portchange);
1801                 if (status < 0
1802                                 || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
1803                                 || (devstatus & USB_PORT_STAT_SUSPEND) != 0
1804                                 ) {
1805                         dev_dbg(hub->intfdev,
1806                                 "port %d status %04x.%04x after resume, %d\n",
1807                                 port1, portchange, devstatus, status);
1808                 } else {
1809                         /* TRSMRCY = 10 msec */
1810                         msleep(10);
1811                         if (udev)
1812                                 status = finish_port_resume(udev);
1813                 }
1814         }
1815         if (status < 0)
1816                 hub_port_logical_disconnect(hub, port1);
1817
1818         return status;
1819 }
1820
1821 static int hub_resume (struct usb_interface *intf);
1822
1823 /**
1824  * usb_resume_device - re-activate a suspended usb device
1825  * @udev: device to re-activate
1826  * Context: must be able to sleep; device not locked
1827  *
1828  * This will re-activate the suspended device, increasing power usage
1829  * while letting drivers communicate again with its endpoints.
1830  * USB resume explicitly guarantees that the power session between
1831  * the host and the device is the same as it was when the device
1832  * suspended.
1833  *
1834  * Returns 0 on success, else negative errno.
1835  */
1836 int usb_resume_device(struct usb_device *udev)
1837 {
1838         int     port1, status;
1839
1840         port1 = locktree(udev);
1841         if (port1 < 0)
1842                 return port1;
1843
1844         /* "global resume" of the HC-to-USB interface (root hub), or
1845          * selective resume of one hub-to-device port
1846          */
1847         if (!udev->parent) {
1848                 struct usb_bus  *bus = udev->bus;
1849                 if (bus && bus->op->hub_resume) {
1850                         status = bus->op->hub_resume (bus);
1851                 } else
1852                         status = -EOPNOTSUPP;
1853                 if (status == 0) {
1854                         dev_dbg(&udev->dev, "usb resume\n");
1855                         /* TRSMRCY = 10 msec */
1856                         msleep(10);
1857                         usb_set_device_state (udev, USB_STATE_CONFIGURED);
1858                         udev->dev.power.power_state = PMSG_ON;
1859                         status = hub_resume (udev
1860                                         ->actconfig->interface[0]);
1861                 }
1862         } else if (udev->state == USB_STATE_SUSPENDED) {
1863                 // NOTE this fails if parent is also suspended...
1864                 status = hub_port_resume(hdev_to_hub(udev->parent),
1865                                 port1, udev);
1866         } else {
1867                 status = 0;
1868         }
1869         if (status < 0) {
1870                 dev_dbg(&udev->dev, "can't resume, status %d\n",
1871                         status);
1872         }
1873
1874         usb_unlock_device(udev);
1875
1876         /* rebind drivers that had no suspend() */
1877         if (status == 0) {
1878                 usb_lock_all_devices();
1879                 bus_rescan_devices(&usb_bus_type);
1880                 usb_unlock_all_devices();
1881         }
1882         return status;
1883 }
1884
1885 static int remote_wakeup(struct usb_device *udev)
1886 {
1887         int     status = 0;
1888
1889         /* don't repeat RESUME sequence if this device
1890          * was already woken up by some other task
1891          */
1892         down(&udev->serialize);
1893         if (udev->state == USB_STATE_SUSPENDED) {
1894                 dev_dbg(&udev->dev, "RESUME (wakeup)\n");
1895                 /* TRSMRCY = 10 msec */
1896                 msleep(10);
1897                 status = finish_port_resume(udev);
1898         }
1899         up(&udev->serialize);
1900         return status;
1901 }
1902
1903 static int hub_suspend(struct usb_interface *intf, pm_message_t state)
1904 {
1905         struct usb_hub          *hub = usb_get_intfdata (intf);
1906         struct usb_device       *hdev = hub->hdev;
1907         unsigned                port1;
1908         int                     status;
1909
1910         /* stop khubd and related activity */
1911         hub_quiesce(hub);
1912
1913         /* then suspend every port */
1914         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1915                 struct usb_device       *udev;
1916
1917                 udev = hdev->children [port1-1];
1918                 if (!udev)
1919                         continue;
1920                 down(&udev->serialize);
1921                 status = __usb_suspend_device(udev, port1, state);
1922                 up(&udev->serialize);
1923                 if (status < 0)
1924                         dev_dbg(&intf->dev, "suspend port %d --> %d\n",
1925                                 port1, status);
1926         }
1927
1928         intf->dev.power.power_state = state;
1929         return 0;
1930 }
1931
1932 static int hub_resume(struct usb_interface *intf)
1933 {
1934         struct usb_device       *hdev = interface_to_usbdev(intf);
1935         struct usb_hub          *hub = usb_get_intfdata (intf);
1936         unsigned                port1;
1937         int                     status;
1938
1939         if (intf->dev.power.power_state.event == PM_EVENT_ON)
1940                 return 0;
1941
1942         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1943                 struct usb_device       *udev;
1944                 u16                     portstat, portchange;
1945
1946                 udev = hdev->children [port1-1];
1947                 status = hub_port_status(hub, port1, &portstat, &portchange);
1948                 if (status == 0) {
1949                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
1950                                 clear_port_feature(hdev, port1,
1951                                         USB_PORT_FEAT_C_SUSPEND);
1952                                 portchange &= ~USB_PORT_STAT_C_SUSPEND;
1953                         }
1954
1955                         /* let khubd handle disconnects etc */
1956                         if (portchange)
1957                                 continue;
1958                 }
1959
1960                 if (!udev || status < 0)
1961                         continue;
1962                 down (&udev->serialize);
1963                 if (portstat & USB_PORT_STAT_SUSPEND)
1964                         status = hub_port_resume(hub, port1, udev);
1965                 else {
1966                         status = finish_port_resume(udev);
1967                         if (status < 0) {
1968                                 dev_dbg(&intf->dev, "resume port %d --> %d\n",
1969                                         port1, status);
1970                                 hub_port_logical_disconnect(hub, port1);
1971                         }
1972                 }
1973                 up(&udev->serialize);
1974         }
1975         intf->dev.power.power_state = PMSG_ON;
1976
1977         hub->resume_root_hub = 0;
1978         hub_activate(hub);
1979         return 0;
1980 }
1981
1982 void usb_resume_root_hub(struct usb_device *hdev)
1983 {
1984         struct usb_hub *hub = hdev_to_hub(hdev);
1985
1986         hub->resume_root_hub = 1;
1987         kick_khubd(hub);
1988 }
1989
1990 #else   /* !CONFIG_USB_SUSPEND */
1991
1992 int usb_suspend_device(struct usb_device *udev, pm_message_t state)
1993 {
1994         return 0;
1995 }
1996
1997 int usb_resume_device(struct usb_device *udev)
1998 {
1999         return 0;
2000 }
2001
2002 #define hub_suspend             NULL
2003 #define hub_resume              NULL
2004 #define remote_wakeup(x)        0
2005
2006 #endif  /* CONFIG_USB_SUSPEND */
2007
2008 EXPORT_SYMBOL(usb_suspend_device);
2009 EXPORT_SYMBOL(usb_resume_device);
2010
2011
2012
2013 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2014  *
2015  * Between connect detection and reset signaling there must be a delay
2016  * of 100ms at least for debounce and power-settling.  The corresponding
2017  * timer shall restart whenever the downstream port detects a disconnect.
2018  *
2019  * Apparently there are some bluetooth and irda-dongles and a number of
2020  * low-speed devices for which this debounce period may last over a second.
2021  * Not covered by the spec - but easy to deal with.
2022  *
2023  * This implementation uses a 1500ms total debounce timeout; if the
2024  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
2025  * every 25ms for transient disconnects.  When the port status has been
2026  * unchanged for 100ms it returns the port status.
2027  */
2028
2029 #define HUB_DEBOUNCE_TIMEOUT    1500
2030 #define HUB_DEBOUNCE_STEP         25
2031 #define HUB_DEBOUNCE_STABLE      100
2032
2033 static int hub_port_debounce(struct usb_hub *hub, int port1)
2034 {
2035         int ret;
2036         int total_time, stable_time = 0;
2037         u16 portchange, portstatus;
2038         unsigned connection = 0xffff;
2039
2040         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2041                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2042                 if (ret < 0)
2043                         return ret;
2044
2045                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2046                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2047                         stable_time += HUB_DEBOUNCE_STEP;
2048                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2049                                 break;
2050                 } else {
2051                         stable_time = 0;
2052                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2053                 }
2054
2055                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2056                         clear_port_feature(hub->hdev, port1,
2057                                         USB_PORT_FEAT_C_CONNECTION);
2058                 }
2059
2060                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2061                         break;
2062                 msleep(HUB_DEBOUNCE_STEP);
2063         }
2064
2065         dev_dbg (hub->intfdev,
2066                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2067                 port1, total_time, stable_time, portstatus);
2068
2069         if (stable_time < HUB_DEBOUNCE_STABLE)
2070                 return -ETIMEDOUT;
2071         return portstatus;
2072 }
2073
2074 static void ep0_reinit(struct usb_device *udev)
2075 {
2076         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2077         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2078         udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2079 }
2080
2081 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2082 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2083
2084 static int hub_set_address(struct usb_device *udev)
2085 {
2086         int retval;
2087
2088         if (udev->devnum == 0)
2089                 return -EINVAL;
2090         if (udev->state == USB_STATE_ADDRESS)
2091                 return 0;
2092         if (udev->state != USB_STATE_DEFAULT)
2093                 return -EINVAL;
2094         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2095                 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2096                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2097         if (retval == 0) {
2098                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2099                 ep0_reinit(udev);
2100         }
2101         return retval;
2102 }
2103
2104 /* Reset device, (re)assign address, get device descriptor.
2105  * Device connection must be stable, no more debouncing needed.
2106  * Returns device in USB_STATE_ADDRESS, except on error.
2107  *
2108  * If this is called for an already-existing device (as part of
2109  * usb_reset_device), the caller must own the device lock.  For a
2110  * newly detected device that is not accessible through any global
2111  * pointers, it's not necessary to lock the device.
2112  */
2113 static int
2114 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2115                 int retry_counter)
2116 {
2117         static DECLARE_MUTEX(usb_address0_sem);
2118
2119         struct usb_device       *hdev = hub->hdev;
2120         int                     i, j, retval;
2121         unsigned                delay = HUB_SHORT_RESET_TIME;
2122         enum usb_device_speed   oldspeed = udev->speed;
2123
2124         /* root hub ports have a slightly longer reset period
2125          * (from USB 2.0 spec, section 7.1.7.5)
2126          */
2127         if (!hdev->parent) {
2128                 delay = HUB_ROOT_RESET_TIME;
2129                 if (port1 == hdev->bus->otg_port)
2130                         hdev->bus->b_hnp_enable = 0;
2131         }
2132
2133         /* Some low speed devices have problems with the quick delay, so */
2134         /*  be a bit pessimistic with those devices. RHbug #23670 */
2135         if (oldspeed == USB_SPEED_LOW)
2136                 delay = HUB_LONG_RESET_TIME;
2137
2138         down(&usb_address0_sem);
2139
2140         /* Reset the device; full speed may morph to high speed */
2141         retval = hub_port_reset(hub, port1, udev, delay);
2142         if (retval < 0)         /* error or disconnect */
2143                 goto fail;
2144                                 /* success, speed is known */
2145         retval = -ENODEV;
2146
2147         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2148                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2149                 goto fail;
2150         }
2151         oldspeed = udev->speed;
2152
2153         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2154          * it's fixed size except for full speed devices.
2155          */
2156         switch (udev->speed) {
2157         case USB_SPEED_HIGH:            /* fixed at 64 */
2158                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2159                 break;
2160         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2161                 /* to determine the ep0 maxpacket size, try to read
2162                  * the device descriptor to get bMaxPacketSize0 and
2163                  * then correct our initial guess.
2164                  */
2165                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2166                 break;
2167         case USB_SPEED_LOW:             /* fixed at 8 */
2168                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2169                 break;
2170         default:
2171                 goto fail;
2172         }
2173
2174         dev_info (&udev->dev,
2175                         "%s %s speed USB device using %s and address %d\n",
2176                         (udev->config) ? "reset" : "new",
2177                         ({ char *speed; switch (udev->speed) {
2178                         case USB_SPEED_LOW:     speed = "low";  break;
2179                         case USB_SPEED_FULL:    speed = "full"; break;
2180                         case USB_SPEED_HIGH:    speed = "high"; break;
2181                         default:                speed = "?";    break;
2182                         }; speed;}),
2183                         udev->bus->controller->driver->name,
2184                         udev->devnum);
2185
2186         /* Set up TT records, if needed  */
2187         if (hdev->tt) {
2188                 udev->tt = hdev->tt;
2189                 udev->ttport = hdev->ttport;
2190         } else if (udev->speed != USB_SPEED_HIGH
2191                         && hdev->speed == USB_SPEED_HIGH) {
2192                 udev->tt = &hub->tt;
2193                 udev->ttport = port1;
2194         }
2195
2196         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2197          * Because device hardware and firmware is sometimes buggy in
2198          * this area, and this is how Linux has done it for ages.
2199          * Change it cautiously.
2200          *
2201          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2202          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2203          * so it may help with some non-standards-compliant devices.
2204          * Otherwise we start with SET_ADDRESS and then try to read the
2205          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2206          * value.
2207          */
2208         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2209                 if (USE_NEW_SCHEME(retry_counter)) {
2210                         struct usb_device_descriptor *buf;
2211                         int r = 0;
2212
2213 #define GET_DESCRIPTOR_BUFSIZE  64
2214                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2215                         if (!buf) {
2216                                 retval = -ENOMEM;
2217                                 continue;
2218                         }
2219
2220                         /* Use a short timeout the first time through,
2221                          * so that recalcitrant full-speed devices with
2222                          * 8- or 16-byte ep0-maxpackets won't slow things
2223                          * down tremendously by NAKing the unexpectedly
2224                          * early status stage.  Also, retry on all errors;
2225                          * some devices are flakey.
2226                          */
2227                         for (j = 0; j < 3; ++j) {
2228                                 buf->bMaxPacketSize0 = 0;
2229                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2230                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2231                                         USB_DT_DEVICE << 8, 0,
2232                                         buf, GET_DESCRIPTOR_BUFSIZE,
2233                                         (i ? USB_CTRL_GET_TIMEOUT : 1000));
2234                                 switch (buf->bMaxPacketSize0) {
2235                                 case 8: case 16: case 32: case 64:
2236                                         if (buf->bDescriptorType ==
2237                                                         USB_DT_DEVICE) {
2238                                                 r = 0;
2239                                                 break;
2240                                         }
2241                                         /* FALL THROUGH */
2242                                 default:
2243                                         if (r == 0)
2244                                                 r = -EPROTO;
2245                                         break;
2246                                 }
2247                                 if (r == 0)
2248                                         break;
2249                         }
2250                         udev->descriptor.bMaxPacketSize0 =
2251                                         buf->bMaxPacketSize0;
2252                         kfree(buf);
2253
2254                         retval = hub_port_reset(hub, port1, udev, delay);
2255                         if (retval < 0)         /* error or disconnect */
2256                                 goto fail;
2257                         if (oldspeed != udev->speed) {
2258                                 dev_dbg(&udev->dev,
2259                                         "device reset changed speed!\n");
2260                                 retval = -ENODEV;
2261                                 goto fail;
2262                         }
2263                         if (r) {
2264                                 dev_err(&udev->dev, "device descriptor "
2265                                                 "read/%s, error %d\n",
2266                                                 "64", r);
2267                                 retval = -EMSGSIZE;
2268                                 continue;
2269                         }
2270 #undef GET_DESCRIPTOR_BUFSIZE
2271                 }
2272
2273                 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2274                         retval = hub_set_address(udev);
2275                         if (retval >= 0)
2276                                 break;
2277                         msleep(200);
2278                 }
2279                 if (retval < 0) {
2280                         dev_err(&udev->dev,
2281                                 "device not accepting address %d, error %d\n",
2282                                 udev->devnum, retval);
2283                         goto fail;
2284                 }
2285
2286                 /* cope with hardware quirkiness:
2287                  *  - let SET_ADDRESS settle, some device hardware wants it
2288                  *  - read ep0 maxpacket even for high and low speed,
2289                  */
2290                 msleep(10);
2291                 if (USE_NEW_SCHEME(retry_counter))
2292                         break;
2293
2294                 retval = usb_get_device_descriptor(udev, 8);
2295                 if (retval < 8) {
2296                         dev_err(&udev->dev, "device descriptor "
2297                                         "read/%s, error %d\n",
2298                                         "8", retval);
2299                         if (retval >= 0)
2300                                 retval = -EMSGSIZE;
2301                 } else {
2302                         retval = 0;
2303                         break;
2304                 }
2305         }
2306         if (retval)
2307                 goto fail;
2308
2309         i = udev->descriptor.bMaxPacketSize0;
2310         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2311                 if (udev->speed != USB_SPEED_FULL ||
2312                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2313                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2314                         retval = -EMSGSIZE;
2315                         goto fail;
2316                 }
2317                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2318                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2319                 ep0_reinit(udev);
2320         }
2321
2322         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2323         if (retval < (signed)sizeof(udev->descriptor)) {
2324                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2325                         "all", retval);
2326                 if (retval >= 0)
2327                         retval = -ENOMSG;
2328                 goto fail;
2329         }
2330
2331         retval = 0;
2332
2333 fail:
2334         if (retval)
2335                 hub_port_disable(hub, port1, 0);
2336         up(&usb_address0_sem);
2337         return retval;
2338 }
2339
2340 static void
2341 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2342 {
2343         struct usb_qualifier_descriptor *qual;
2344         int                             status;
2345
2346         qual = kmalloc (sizeof *qual, SLAB_KERNEL);
2347         if (qual == NULL)
2348                 return;
2349
2350         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2351                         qual, sizeof *qual);
2352         if (status == sizeof *qual) {
2353                 dev_info(&udev->dev, "not running at top speed; "
2354                         "connect to a high speed hub\n");
2355                 /* hub LEDs are probably harder to miss than syslog */
2356                 if (hub->has_indicators) {
2357                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2358                         schedule_work (&hub->leds);
2359                 }
2360         }
2361         kfree(qual);
2362 }
2363
2364 static unsigned
2365 hub_power_remaining (struct usb_hub *hub)
2366 {
2367         struct usb_device *hdev = hub->hdev;
2368         int remaining;
2369         unsigned i;
2370
2371         remaining = hub->power_budget;
2372         if (!remaining)         /* self-powered */
2373                 return 0;
2374
2375         for (i = 0; i < hdev->maxchild; i++) {
2376                 struct usb_device       *udev = hdev->children[i];
2377                 int                     delta, ceiling;
2378
2379                 if (!udev)
2380                         continue;
2381
2382                 /* 100mA per-port ceiling, or 8mA for OTG ports */
2383                 if (i != (udev->bus->otg_port - 1) || hdev->parent)
2384                         ceiling = 50;
2385                 else
2386                         ceiling = 4;
2387
2388                 if (udev->actconfig)
2389                         delta = udev->actconfig->desc.bMaxPower;
2390                 else
2391                         delta = ceiling;
2392                 // dev_dbg(&udev->dev, "budgeted %dmA\n", 2 * delta);
2393                 if (delta > ceiling)
2394                         dev_warn(&udev->dev, "%dmA over %dmA budget!\n",
2395                                 2 * (delta - ceiling), 2 * ceiling);
2396                 remaining -= delta;
2397         }
2398         if (remaining < 0) {
2399                 dev_warn(hub->intfdev,
2400                         "%dmA over power budget!\n",
2401                         -2 * remaining);
2402                 remaining = 0;
2403         }
2404         return remaining;
2405 }
2406
2407 /* Handle physical or logical connection change events.
2408  * This routine is called when:
2409  *      a port connection-change occurs;
2410  *      a port enable-change occurs (often caused by EMI);
2411  *      usb_reset_device() encounters changed descriptors (as from
2412  *              a firmware download)
2413  * caller already locked the hub
2414  */
2415 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2416                                         u16 portstatus, u16 portchange)
2417 {
2418         struct usb_device *hdev = hub->hdev;
2419         struct device *hub_dev = hub->intfdev;
2420         int status, i;
2421
2422         dev_dbg (hub_dev,
2423                 "port %d, status %04x, change %04x, %s\n",
2424                 port1, portstatus, portchange, portspeed (portstatus));
2425
2426         if (hub->has_indicators) {
2427                 set_port_led(hub, port1, HUB_LED_AUTO);
2428                 hub->indicator[port1-1] = INDICATOR_AUTO;
2429         }
2430
2431         /* Disconnect any existing devices under this port */
2432         if (hdev->children[port1-1])
2433                 usb_disconnect(&hdev->children[port1-1]);
2434         clear_bit(port1, hub->change_bits);
2435
2436 #ifdef  CONFIG_USB_OTG
2437         /* during HNP, don't repeat the debounce */
2438         if (hdev->bus->is_b_host)
2439                 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2440 #endif
2441
2442         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2443                 status = hub_port_debounce(hub, port1);
2444                 if (status < 0) {
2445                         dev_err (hub_dev,
2446                                 "connect-debounce failed, port %d disabled\n",
2447                                 port1);
2448                         goto done;
2449                 }
2450                 portstatus = status;
2451         }
2452
2453         /* Return now if nothing is connected */
2454         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2455
2456                 /* maybe switch power back on (e.g. root hub was reset) */
2457                 if ((hub->descriptor->wHubCharacteristics
2458                                         & HUB_CHAR_LPSM) < 2
2459                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2460                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2461
2462                 if (portstatus & USB_PORT_STAT_ENABLE)
2463                         goto done;
2464                 return;
2465         }
2466
2467 #ifdef  CONFIG_USB_SUSPEND
2468         /* If something is connected, but the port is suspended, wake it up. */
2469         if (portstatus & USB_PORT_STAT_SUSPEND) {
2470                 status = hub_port_resume(hub, port1, NULL);
2471                 if (status < 0) {
2472                         dev_dbg(hub_dev,
2473                                 "can't clear suspend on port %d; %d\n",
2474                                 port1, status);
2475                         goto done;
2476                 }
2477         }
2478 #endif
2479
2480         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2481                 struct usb_device *udev;
2482
2483                 /* reallocate for each attempt, since references
2484                  * to the previous one can escape in various ways
2485                  */
2486                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2487                 if (!udev) {
2488                         dev_err (hub_dev,
2489                                 "couldn't allocate port %d usb_device\n",
2490                                 port1);
2491                         goto done;
2492                 }
2493
2494                 usb_set_device_state(udev, USB_STATE_POWERED);
2495                 udev->speed = USB_SPEED_UNKNOWN;
2496
2497                 /* set the address */
2498                 choose_address(udev);
2499                 if (udev->devnum <= 0) {
2500                         status = -ENOTCONN;     /* Don't retry */
2501                         goto loop;
2502                 }
2503
2504                 /* reset and get descriptor */
2505                 status = hub_port_init(hub, udev, port1, i);
2506                 if (status < 0)
2507                         goto loop;
2508
2509                 /* consecutive bus-powered hubs aren't reliable; they can
2510                  * violate the voltage drop budget.  if the new child has
2511                  * a "powered" LED, users should notice we didn't enable it
2512                  * (without reading syslog), even without per-port LEDs
2513                  * on the parent.
2514                  */
2515                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2516                                 && hub->power_budget) {
2517                         u16     devstat;
2518
2519                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2520                                         &devstat);
2521                         if (status < 0) {
2522                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2523                                 goto loop_disable;
2524                         }
2525                         cpu_to_le16s(&devstat);
2526                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2527                                 dev_err(&udev->dev,
2528                                         "can't connect bus-powered hub "
2529                                         "to this port\n");
2530                                 if (hub->has_indicators) {
2531                                         hub->indicator[port1-1] =
2532                                                 INDICATOR_AMBER_BLINK;
2533                                         schedule_work (&hub->leds);
2534                                 }
2535                                 status = -ENOTCONN;     /* Don't retry */
2536                                 goto loop_disable;
2537                         }
2538                 }
2539
2540                 /* check for devices running slower than they could */
2541                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2542                                 && udev->speed == USB_SPEED_FULL
2543                                 && highspeed_hubs != 0)
2544                         check_highspeed (hub, udev, port1);
2545
2546                 /* Store the parent's children[] pointer.  At this point
2547                  * udev becomes globally accessible, although presumably
2548                  * no one will look at it until hdev is unlocked.
2549                  */
2550                 down (&udev->serialize);
2551                 status = 0;
2552
2553                 /* We mustn't add new devices if the parent hub has
2554                  * been disconnected; we would race with the
2555                  * recursively_mark_NOTATTACHED() routine.
2556                  */
2557                 spin_lock_irq(&device_state_lock);
2558                 if (hdev->state == USB_STATE_NOTATTACHED)
2559                         status = -ENOTCONN;
2560                 else
2561                         hdev->children[port1-1] = udev;
2562                 spin_unlock_irq(&device_state_lock);
2563
2564                 /* Run it through the hoops (find a driver, etc) */
2565                 if (!status) {
2566                         status = usb_new_device(udev);
2567                         if (status) {
2568                                 spin_lock_irq(&device_state_lock);
2569                                 hdev->children[port1-1] = NULL;
2570                                 spin_unlock_irq(&device_state_lock);
2571                         }
2572                 }
2573
2574                 up (&udev->serialize);
2575                 if (status)
2576                         goto loop_disable;
2577
2578                 status = hub_power_remaining(hub);
2579                 if (status)
2580                         dev_dbg(hub_dev,
2581                                 "%dmA power budget left\n",
2582                                 2 * status);
2583
2584                 return;
2585
2586 loop_disable:
2587                 hub_port_disable(hub, port1, 1);
2588 loop:
2589                 ep0_reinit(udev);
2590                 release_address(udev);
2591                 usb_put_dev(udev);
2592                 if (status == -ENOTCONN)
2593                         break;
2594         }
2595
2596 done:
2597         hub_port_disable(hub, port1, 1);
2598 }
2599
2600 static void hub_events(void)
2601 {
2602         struct list_head *tmp;
2603         struct usb_device *hdev;
2604         struct usb_interface *intf;
2605         struct usb_hub *hub;
2606         struct device *hub_dev;
2607         u16 hubstatus;
2608         u16 hubchange;
2609         u16 portstatus;
2610         u16 portchange;
2611         int i, ret;
2612         int connect_change;
2613
2614         /*
2615          *  We restart the list every time to avoid a deadlock with
2616          * deleting hubs downstream from this one. This should be
2617          * safe since we delete the hub from the event list.
2618          * Not the most efficient, but avoids deadlocks.
2619          */
2620         while (1) {
2621
2622                 /* Grab the first entry at the beginning of the list */
2623                 spin_lock_irq(&hub_event_lock);
2624                 if (list_empty(&hub_event_list)) {
2625                         spin_unlock_irq(&hub_event_lock);
2626                         break;
2627                 }
2628
2629                 tmp = hub_event_list.next;
2630                 list_del_init(tmp);
2631
2632                 hub = list_entry(tmp, struct usb_hub, event_list);
2633                 hdev = hub->hdev;
2634                 intf = to_usb_interface(hub->intfdev);
2635                 hub_dev = &intf->dev;
2636
2637                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
2638                                 hdev->state, hub->descriptor
2639                                         ? hub->descriptor->bNbrPorts
2640                                         : 0,
2641                                 /* NOTE: expects max 15 ports... */
2642                                 (u16) hub->change_bits[0],
2643                                 (u16) hub->event_bits[0]);
2644
2645                 usb_get_intf(intf);
2646                 i = hub->resume_root_hub;
2647                 spin_unlock_irq(&hub_event_lock);
2648
2649                 /* Is this is a root hub wanting to be resumed? */
2650                 if (i)
2651                         usb_resume_device(hdev);
2652
2653                 /* Lock the device, then check to see if we were
2654                  * disconnected while waiting for the lock to succeed. */
2655                 if (locktree(hdev) < 0) {
2656                         usb_put_intf(intf);
2657                         continue;
2658                 }
2659                 if (hub != usb_get_intfdata(intf))
2660                         goto loop;
2661
2662                 /* If the hub has died, clean up after it */
2663                 if (hdev->state == USB_STATE_NOTATTACHED) {
2664                         hub_pre_reset(hub);
2665                         goto loop;
2666                 }
2667
2668                 /* If this is an inactive or suspended hub, do nothing */
2669                 if (hub->quiescing)
2670                         goto loop;
2671
2672                 if (hub->error) {
2673                         dev_dbg (hub_dev, "resetting for error %d\n",
2674                                 hub->error);
2675
2676                         ret = usb_reset_device(hdev);
2677                         if (ret) {
2678                                 dev_dbg (hub_dev,
2679                                         "error resetting hub: %d\n", ret);
2680                                 goto loop;
2681                         }
2682
2683                         hub->nerrors = 0;
2684                         hub->error = 0;
2685                 }
2686
2687                 /* deal with port status changes */
2688                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2689                         if (test_bit(i, hub->busy_bits))
2690                                 continue;
2691                         connect_change = test_bit(i, hub->change_bits);
2692                         if (!test_and_clear_bit(i, hub->event_bits) &&
2693                                         !connect_change && !hub->activating)
2694                                 continue;
2695
2696                         ret = hub_port_status(hub, i,
2697                                         &portstatus, &portchange);
2698                         if (ret < 0)
2699                                 continue;
2700
2701                         if (hub->activating && !hdev->children[i-1] &&
2702                                         (portstatus &
2703                                                 USB_PORT_STAT_CONNECTION))
2704                                 connect_change = 1;
2705
2706                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2707                                 clear_port_feature(hdev, i,
2708                                         USB_PORT_FEAT_C_CONNECTION);
2709                                 connect_change = 1;
2710                         }
2711
2712                         if (portchange & USB_PORT_STAT_C_ENABLE) {
2713                                 if (!connect_change)
2714                                         dev_dbg (hub_dev,
2715                                                 "port %d enable change, "
2716                                                 "status %08x\n",
2717                                                 i, portstatus);
2718                                 clear_port_feature(hdev, i,
2719                                         USB_PORT_FEAT_C_ENABLE);
2720
2721                                 /*
2722                                  * EM interference sometimes causes badly
2723                                  * shielded USB devices to be shutdown by
2724                                  * the hub, this hack enables them again.
2725                                  * Works at least with mouse driver.
2726                                  */
2727                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
2728                                     && !connect_change
2729                                     && hdev->children[i-1]) {
2730                                         dev_err (hub_dev,
2731                                             "port %i "
2732                                             "disabled by hub (EMI?), "
2733                                             "re-enabling...\n",
2734                                                 i);
2735                                         connect_change = 1;
2736                                 }
2737                         }
2738
2739                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2740                                 clear_port_feature(hdev, i,
2741                                         USB_PORT_FEAT_C_SUSPEND);
2742                                 if (hdev->children[i-1]) {
2743                                         ret = remote_wakeup(hdev->
2744                                                         children[i-1]);
2745                                         if (ret < 0)
2746                                                 connect_change = 1;
2747                                 } else {
2748                                         ret = -ENODEV;
2749                                         hub_port_disable(hub, i, 1);
2750                                 }
2751                                 dev_dbg (hub_dev,
2752                                         "resume on port %d, status %d\n",
2753                                         i, ret);
2754                         }
2755
2756                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2757                                 dev_err (hub_dev,
2758                                         "over-current change on port %d\n",
2759                                         i);
2760                                 clear_port_feature(hdev, i,
2761                                         USB_PORT_FEAT_C_OVER_CURRENT);
2762                                 hub_power_on(hub);
2763                         }
2764
2765                         if (portchange & USB_PORT_STAT_C_RESET) {
2766                                 dev_dbg (hub_dev,
2767                                         "reset change on port %d\n",
2768                                         i);
2769                                 clear_port_feature(hdev, i,
2770                                         USB_PORT_FEAT_C_RESET);
2771                         }
2772
2773                         if (connect_change)
2774                                 hub_port_connect_change(hub, i,
2775                                                 portstatus, portchange);
2776                 } /* end for i */
2777
2778                 /* deal with hub status changes */
2779                 if (test_and_clear_bit(0, hub->event_bits) == 0)
2780                         ;       /* do nothing */
2781                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2782                         dev_err (hub_dev, "get_hub_status failed\n");
2783                 else {
2784                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2785                                 dev_dbg (hub_dev, "power change\n");
2786                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2787                         }
2788                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
2789                                 dev_dbg (hub_dev, "overcurrent change\n");
2790                                 msleep(500);    /* Cool down */
2791                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2792                                 hub_power_on(hub);
2793                         }
2794                 }
2795
2796                 hub->activating = 0;
2797
2798                 /* If this is a root hub, tell the HCD it's okay to
2799                  * re-enable port-change interrupts now. */
2800                 if (!hdev->parent)
2801                         usb_enable_root_hub_irq(hdev->bus);
2802
2803 loop:
2804                 usb_unlock_device(hdev);
2805                 usb_put_intf(intf);
2806
2807         } /* end while (1) */
2808 }
2809
2810 static int hub_thread(void *__unused)
2811 {
2812         do {
2813                 hub_events();
2814                 wait_event_interruptible(khubd_wait,
2815                                 !list_empty(&hub_event_list) ||
2816                                 kthread_should_stop());
2817                 try_to_freeze();
2818         } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2819
2820         pr_debug("%s: khubd exiting\n", usbcore_name);
2821         return 0;
2822 }
2823
2824 static struct usb_device_id hub_id_table [] = {
2825     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2826       .bDeviceClass = USB_CLASS_HUB},
2827     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2828       .bInterfaceClass = USB_CLASS_HUB},
2829     { }                                         /* Terminating entry */
2830 };
2831
2832 MODULE_DEVICE_TABLE (usb, hub_id_table);
2833
2834 static struct usb_driver hub_driver = {
2835         .owner =        THIS_MODULE,
2836         .name =         "hub",
2837         .probe =        hub_probe,
2838         .disconnect =   hub_disconnect,
2839         .suspend =      hub_suspend,
2840         .resume =       hub_resume,
2841         .ioctl =        hub_ioctl,
2842         .id_table =     hub_id_table,
2843 };
2844
2845 int usb_hub_init(void)
2846 {
2847         if (usb_register(&hub_driver) < 0) {
2848                 printk(KERN_ERR "%s: can't register hub driver\n",
2849                         usbcore_name);
2850                 return -1;
2851         }
2852
2853         khubd_task = kthread_run(hub_thread, NULL, "khubd");
2854         if (!IS_ERR(khubd_task))
2855                 return 0;
2856
2857         /* Fall through if kernel_thread failed */
2858         usb_deregister(&hub_driver);
2859         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2860
2861         return -1;
2862 }
2863
2864 void usb_hub_cleanup(void)
2865 {
2866         kthread_stop(khubd_task);
2867
2868         /*
2869          * Hub resources are freed for us by usb_deregister. It calls
2870          * usb_driver_purge on every device which in turn calls that
2871          * devices disconnect function if it is using this driver.
2872          * The hub_disconnect function takes care of releasing the
2873          * individual hub resources. -greg
2874          */
2875         usb_deregister(&hub_driver);
2876 } /* usb_hub_cleanup() */
2877
2878 static int config_descriptors_changed(struct usb_device *udev)
2879 {
2880         unsigned                        index;
2881         unsigned                        len = 0;
2882         struct usb_config_descriptor    *buf;
2883
2884         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2885                 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2886                         len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2887         }
2888         buf = kmalloc (len, SLAB_KERNEL);
2889         if (buf == NULL) {
2890                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2891                 /* assume the worst */
2892                 return 1;
2893         }
2894         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2895                 int length;
2896                 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2897
2898                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2899                                 old_length);
2900                 if (length < old_length) {
2901                         dev_dbg(&udev->dev, "config index %d, error %d\n",
2902                                         index, length);
2903                         break;
2904                 }
2905                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2906                                 != 0) {
2907                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2908                                 index, buf->bConfigurationValue);
2909                         break;
2910                 }
2911         }
2912         kfree(buf);
2913         return index != udev->descriptor.bNumConfigurations;
2914 }
2915
2916 /**
2917  * usb_reset_device - perform a USB port reset to reinitialize a device
2918  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2919  *
2920  * WARNING - don't reset any device unless drivers for all of its
2921  * interfaces are expecting that reset!  Maybe some driver->reset()
2922  * method should eventually help ensure sufficient cooperation.
2923  *
2924  * Do a port reset, reassign the device's address, and establish its
2925  * former operating configuration.  If the reset fails, or the device's
2926  * descriptors change from their values before the reset, or the original
2927  * configuration and altsettings cannot be restored, a flag will be set
2928  * telling khubd to pretend the device has been disconnected and then
2929  * re-connected.  All drivers will be unbound, and the device will be
2930  * re-enumerated and probed all over again.
2931  *
2932  * Returns 0 if the reset succeeded, -ENODEV if the device has been
2933  * flagged for logical disconnection, or some other negative error code
2934  * if the reset wasn't even attempted.
2935  *
2936  * The caller must own the device lock.  For example, it's safe to use
2937  * this from a driver probe() routine after downloading new firmware.
2938  * For calls that might not occur during probe(), drivers should lock
2939  * the device using usb_lock_device_for_reset().
2940  */
2941 int usb_reset_device(struct usb_device *udev)
2942 {
2943         struct usb_device               *parent_hdev = udev->parent;
2944         struct usb_hub                  *parent_hub;
2945         struct usb_device_descriptor    descriptor = udev->descriptor;
2946         struct usb_hub                  *hub = NULL;
2947         int                             i, ret = 0, port1 = -1;
2948
2949         if (udev->state == USB_STATE_NOTATTACHED ||
2950                         udev->state == USB_STATE_SUSPENDED) {
2951                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2952                                 udev->state);
2953                 return -EINVAL;
2954         }
2955
2956         if (!parent_hdev) {
2957                 /* this requires hcd-specific logic; see OHCI hc_restart() */
2958                 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2959                 return -EISDIR;
2960         }
2961
2962         for (i = 0; i < parent_hdev->maxchild; i++)
2963                 if (parent_hdev->children[i] == udev) {
2964                         port1 = i + 1;
2965                         break;
2966                 }
2967
2968         if (port1 < 0) {
2969                 /* If this ever happens, it's very bad */
2970                 dev_err(&udev->dev, "Can't locate device's port!\n");
2971                 return -ENOENT;
2972         }
2973         parent_hub = hdev_to_hub(parent_hdev);
2974
2975         /* If we're resetting an active hub, take some special actions */
2976         if (udev->actconfig &&
2977                         udev->actconfig->interface[0]->dev.driver ==
2978                                 &hub_driver.driver &&
2979                         (hub = hdev_to_hub(udev)) != NULL) {
2980                 hub_pre_reset(hub);
2981         }
2982
2983         set_bit(port1, parent_hub->busy_bits);
2984         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
2985
2986                 /* ep0 maxpacket size may change; let the HCD know about it.
2987                  * Other endpoints will be handled by re-enumeration. */
2988                 ep0_reinit(udev);
2989                 ret = hub_port_init(parent_hub, udev, port1, i);
2990                 if (ret >= 0)
2991                         break;
2992         }
2993         clear_bit(port1, parent_hub->busy_bits);
2994         if (ret < 0)
2995                 goto re_enumerate;
2996
2997         /* Device might have changed firmware (DFU or similar) */
2998         if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
2999                         || config_descriptors_changed (udev)) {
3000                 dev_info(&udev->dev, "device firmware changed\n");
3001                 udev->descriptor = descriptor;  /* for disconnect() calls */
3002                 goto re_enumerate;
3003         }
3004
3005         if (!udev->actconfig)
3006                 goto done;
3007
3008         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3009                         USB_REQ_SET_CONFIGURATION, 0,
3010                         udev->actconfig->desc.bConfigurationValue, 0,
3011                         NULL, 0, USB_CTRL_SET_TIMEOUT);
3012         if (ret < 0) {
3013                 dev_err(&udev->dev,
3014                         "can't restore configuration #%d (error=%d)\n",
3015                         udev->actconfig->desc.bConfigurationValue, ret);
3016                 goto re_enumerate;
3017         }
3018         usb_set_device_state(udev, USB_STATE_CONFIGURED);
3019
3020         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3021                 struct usb_interface *intf = udev->actconfig->interface[i];
3022                 struct usb_interface_descriptor *desc;
3023
3024                 /* set_interface resets host side toggle even
3025                  * for altsetting zero.  the interface may have no driver.
3026                  */
3027                 desc = &intf->cur_altsetting->desc;
3028                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3029                         desc->bAlternateSetting);
3030                 if (ret < 0) {
3031                         dev_err(&udev->dev, "failed to restore interface %d "
3032                                 "altsetting %d (error=%d)\n",
3033                                 desc->bInterfaceNumber,
3034                                 desc->bAlternateSetting,
3035                                 ret);
3036                         goto re_enumerate;
3037                 }
3038         }
3039
3040 done:
3041         if (hub)
3042                 hub_post_reset(hub);
3043         return 0;
3044
3045 re_enumerate:
3046         hub_port_logical_disconnect(parent_hub, port1);
3047         return -ENODEV;
3048 }