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
  30 #include <asm/semaphore.h>
  31 #include <asm/uaccess.h>
  32 #include <asm/byteorder.h>
  33
  34 #include "usb.h"
  35 #include "hcd.h"
  36 #include "hub.h"
  37
  38 /* Protect struct usb_device->state and ->children members
  39  * Note: Both are also protected by ->serialize, except that ->state can
  40  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
  41 static DEFINE_SPINLOCK(device_state_lock);
  42
  43 /* khubd's worklist and its lock */
  44 static DEFINE_SPINLOCK(hub_event_lock);
  45 static LIST_HEAD(hub_event_list);       /* List of hubs needing servicing */
  46
  47 /* Wakes up khubd */
  48 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
  49
  50 static pid_t khubd_pid = 0;                     /* PID of khubd */
  51 static DECLARE_COMPLETION(khubd_exited);
  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         cpu_to_le16s(&hubstatus);
 647         if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
 648                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
 649                         hub->descriptor->bHubContrCurrent);
 650                 hub->power_budget = (501 - hub->descriptor->bHubContrCurrent)
 651                                         / 2;
 652                 dev_dbg(hub_dev, "%dmA bus power budget for children\n",
 653                         hub->power_budget * 2);
 654         }
 655
 656
 657         ret = hub_hub_status(hub, &hubstatus, &hubchange);
 658         if (ret < 0) {
 659                 message = "can't get hub status";
 660                 goto fail;
 661         }
 662
 663         /* local power status reports aren't always correct */
 664         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
 665                 dev_dbg(hub_dev, "local power source is %s\n",
 666                         (hubstatus & HUB_STATUS_LOCAL_POWER)
 667                         ? "lost (inactive)" : "good");
 668
 669         if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) == 0)
 670                 dev_dbg(hub_dev, "%sover-current condition exists\n",
 671                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
 672
 673         /* set up the interrupt endpoint */
 674         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
 675         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
 676
 677         if (maxp > sizeof(*hub->buffer))
 678                 maxp = sizeof(*hub->buffer);
 679
 680         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
 681         if (!hub->urb) {
 682                 message = "couldn't allocate interrupt urb";
 683                 ret = -ENOMEM;
 684                 goto fail;
 685         }
 686
 687         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
 688                 hub, endpoint->bInterval);
 689         hub->urb->transfer_dma = hub->buffer_dma;
 690         hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 691
 692         /* maybe cycle the hub leds */
 693         if (hub->has_indicators && blinkenlights)
 694                 hub->indicator [0] = INDICATOR_CYCLE;
 695
 696         hub_power_on(hub);
 697         hub_activate(hub);
 698         return 0;
 699
 700 fail:
 701         dev_err (hub_dev, "config failed, %s (err %d)\n",
 702                         message, ret);
 703         /* hub_disconnect() frees urb and descriptor */
 704         return ret;
 705 }
 706
 707 static unsigned highspeed_hubs;
 708
 709 static void hub_disconnect(struct usb_interface *intf)
 710 {
 711         struct usb_hub *hub = usb_get_intfdata (intf);
 712         struct usb_device *hdev;
 713
 714         if (!hub)
 715                 return;
 716         hdev = hub->hdev;
 717
 718         if (hdev->speed == USB_SPEED_HIGH)
 719                 highspeed_hubs--;
 720
 721         usb_set_intfdata (intf, NULL);
 722
 723         hub_quiesce(hub);
 724         usb_free_urb(hub->urb);
 725         hub->urb = NULL;
 726
 727         spin_lock_irq(&hub_event_lock);
 728         list_del_init(&hub->event_list);
 729         spin_unlock_irq(&hub_event_lock);
 730
 731         kfree(hub->descriptor);
 732         hub->descriptor = NULL;
 733
 734         kfree(hub->status);
 735         hub->status = NULL;
 736
 737         if (hub->buffer) {
 738                 usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
 739                                 hub->buffer_dma);
 740                 hub->buffer = NULL;
 741         }
 742
 743         /* Free the memory */
 744         kfree(hub);
 745 }
 746
 747 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
 748 {
 749         struct usb_host_interface *desc;
 750         struct usb_endpoint_descriptor *endpoint;
 751         struct usb_device *hdev;
 752         struct usb_hub *hub;
 753
 754         desc = intf->cur_altsetting;
 755         hdev = interface_to_usbdev(intf);
 756
 757         /* Some hubs have a subclass of 1, which AFAICT according to the */
 758         /*  specs is not defined, but it works */
 759         if ((desc->desc.bInterfaceSubClass != 0) &&
 760             (desc->desc.bInterfaceSubClass != 1)) {
 761 descriptor_error:
 762                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
 763                 return -EIO;
 764         }
 765
 766         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
 767         if (desc->desc.bNumEndpoints != 1)
 768                 goto descriptor_error;
 769
 770         endpoint = &desc->endpoint[0].desc;
 771
 772         /* Output endpoint? Curiouser and curiouser.. */
 773         if (!(endpoint->bEndpointAddress & USB_DIR_IN))
 774                 goto descriptor_error;
 775
 776         /* If it's not an interrupt endpoint, we'd better punt! */
 777         if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
 778                         != USB_ENDPOINT_XFER_INT)
 779                 goto descriptor_error;
 780
 781         /* We found a hub */
 782         dev_info (&intf->dev, "USB hub found\n");
 783
 784         hub = kmalloc(sizeof(*hub), GFP_KERNEL);
 785         if (!hub) {
 786                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
 787                 return -ENOMEM;
 788         }
 789
 790         memset(hub, 0, sizeof(*hub));
 791
 792         INIT_LIST_HEAD(&hub->event_list);
 793         hub->intfdev = &intf->dev;
 794         hub->hdev = hdev;
 795         INIT_WORK(&hub->leds, led_work, hub);
 796
 797         usb_set_intfdata (intf, hub);
 798
 799         if (hdev->speed == USB_SPEED_HIGH)
 800                 highspeed_hubs++;
 801
 802         if (hub_configure(hub, endpoint) >= 0)
 803                 return 0;
 804
 805         hub_disconnect (intf);
 806         return -ENODEV;
 807 }
 808
 809 static int
 810 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
 811 {
 812         struct usb_device *hdev = interface_to_usbdev (intf);
 813
 814         /* assert ifno == 0 (part of hub spec) */
 815         switch (code) {
 816         case USBDEVFS_HUB_PORTINFO: {
 817                 struct usbdevfs_hub_portinfo *info = user_data;
 818                 int i;
 819
 820                 spin_lock_irq(&device_state_lock);
 821                 if (hdev->devnum <= 0)
 822                         info->nports = 0;
 823                 else {
 824                         info->nports = hdev->maxchild;
 825                         for (i = 0; i < info->nports; i++) {
 826                                 if (hdev->children[i] == NULL)
 827                                         info->port[i] = 0;
 828                                 else
 829                                         info->port[i] =
 830                                                 hdev->children[i]->devnum;
 831                         }
 832                 }
 833                 spin_unlock_irq(&device_state_lock);
 834
 835                 return info->nports + 1;
 836                 }
 837
 838         default:
 839                 return -ENOSYS;
 840         }
 841 }
 842
 843 /* caller has locked the hub device */
 844 static void hub_pre_reset(struct usb_hub *hub)
 845 {
 846         struct usb_device *hdev = hub->hdev;
 847         int i;
 848
 849         for (i = 0; i < hdev->maxchild; ++i) {
 850                 if (hdev->children[i])
 851                         usb_disconnect(&hdev->children[i]);
 852         }
 853         hub_quiesce(hub);
 854 }
 855
 856 /* caller has locked the hub device */
 857 static void hub_post_reset(struct usb_hub *hub)
 858 {
 859         hub_activate(hub);
 860         hub_power_on(hub);
 861 }
 862
 863
 864 /* grab device/port lock, returning index of that port (zero based).
 865  * protects the upstream link used by this device from concurrent
 866  * tree operations like suspend, resume, reset, and disconnect, which
 867  * apply to everything downstream of a given port.
 868  */
 869 static int locktree(struct usb_device *udev)
 870 {
 871         int                     t;
 872         struct usb_device       *hdev;
 873
 874         if (!udev)
 875                 return -ENODEV;
 876
 877         /* root hub is always the first lock in the series */
 878         hdev = udev->parent;
 879         if (!hdev) {
 880                 usb_lock_device(udev);
 881                 return 0;
 882         }
 883
 884         /* on the path from root to us, lock everything from
 885          * top down, dropping parent locks when not needed
 886          */
 887         t = locktree(hdev);
 888         if (t < 0)
 889                 return t;
 890         for (t = 0; t < hdev->maxchild; t++) {
 891                 if (hdev->children[t] == udev) {
 892                         /* everything is fail-fast once disconnect
 893                          * processing starts
 894                          */
 895                         if (udev->state == USB_STATE_NOTATTACHED)
 896                                 break;
 897
 898                         /* when everyone grabs locks top->bottom,
 899                          * non-overlapping work may be concurrent
 900                          */
 901                         down(&udev->serialize);
 902                         up(&hdev->serialize);
 903                         return t + 1;
 904                 }
 905         }
 906         usb_unlock_device(hdev);
 907         return -ENODEV;
 908 }
 909
 910 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
 911 {
 912         int i;
 913
 914         for (i = 0; i < udev->maxchild; ++i) {
 915                 if (udev->children[i])
 916                         recursively_mark_NOTATTACHED(udev->children[i]);
 917         }
 918         udev->state = USB_STATE_NOTATTACHED;
 919 }
 920
 921 /**
 922  * usb_set_device_state - change a device's current state (usbcore, hcds)
 923  * @udev: pointer to device whose state should be changed
 924  * @new_state: new state value to be stored
 925  *
 926  * udev->state is _not_ fully protected by the device lock.  Although
 927  * most transitions are made only while holding the lock, the state can
 928  * can change to USB_STATE_NOTATTACHED at almost any time.  This
 929  * is so that devices can be marked as disconnected as soon as possible,
 930  * without having to wait for any semaphores to be released.  As a result,
 931  * all changes to any device's state must be protected by the
 932  * device_state_lock spinlock.
 933  *
 934  * Once a device has been added to the device tree, all changes to its state
 935  * should be made using this routine.  The state should _not_ be set directly.
 936  *
 937  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
 938  * Otherwise udev->state is set to new_state, and if new_state is
 939  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
 940  * to USB_STATE_NOTATTACHED.
 941  */
 942 void usb_set_device_state(struct usb_device *udev,
 943                 enum usb_device_state new_state)
 944 {
 945         unsigned long flags;
 946
 947         spin_lock_irqsave(&device_state_lock, flags);
 948         if (udev->state == USB_STATE_NOTATTACHED)
 949                 ;       /* do nothing */
 950         else if (new_state != USB_STATE_NOTATTACHED)
 951                 udev->state = new_state;
 952         else
 953                 recursively_mark_NOTATTACHED(udev);
 954         spin_unlock_irqrestore(&device_state_lock, flags);
 955 }
 956 EXPORT_SYMBOL(usb_set_device_state);
 957
 958
 959 static void choose_address(struct usb_device *udev)
 960 {
 961         int             devnum;
 962         struct usb_bus  *bus = udev->bus;
 963
 964         /* If khubd ever becomes multithreaded, this will need a lock */
 965
 966         /* Try to allocate the next devnum beginning at bus->devnum_next. */
 967         devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
 968                         bus->devnum_next);
 969         if (devnum >= 128)
 970                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
 971
 972         bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
 973
 974         if (devnum < 128) {
 975                 set_bit(devnum, bus->devmap.devicemap);
 976                 udev->devnum = devnum;
 977         }
 978 }
 979
 980 static void release_address(struct usb_device *udev)
 981 {
 982         if (udev->devnum > 0) {
 983                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
 984                 udev->devnum = -1;
 985         }
 986 }
 987
 988 /**
 989  * usb_disconnect - disconnect a device (usbcore-internal)
 990  * @pdev: pointer to device being disconnected
 991  * Context: !in_interrupt ()
 992  *
 993  * Something got disconnected. Get rid of it and all of its children.
 994  *
 995  * If *pdev is a normal device then the parent hub must already be locked.
 996  * If *pdev is a root hub then this routine will acquire the
 997  * usb_bus_list_lock on behalf of the caller.
 998  *
 999  * Only hub drivers (including virtual root hub drivers for host
1000  * controllers) should ever call this.
1001  *
1002  * This call is synchronous, and may not be used in an interrupt context.
1003  */
1004 void usb_disconnect(struct usb_device **pdev)
1005 {
1006         struct usb_device       *udev = *pdev;
1007         int                     i;
1008
1009         if (!udev) {
1010                 pr_debug ("%s nodev\n", __FUNCTION__);
1011                 return;
1012         }
1013
1014         /* mark the device as inactive, so any further urb submissions for
1015          * this device (and any of its children) will fail immediately.
1016          * this quiesces everyting except pending urbs.
1017          */
1018         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1019
1020         /* lock the bus list on behalf of HCDs unregistering their root hubs */
1021         if (!udev->parent) {
1022                 down(&usb_bus_list_lock);
1023                 usb_lock_device(udev);
1024         } else
1025                 down(&udev->serialize);
1026
1027         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1028
1029         /* Free up all the children before we remove this device */
1030         for (i = 0; i < USB_MAXCHILDREN; i++) {
1031                 if (udev->children[i])
1032                         usb_disconnect(&udev->children[i]);
1033         }
1034
1035         /* deallocate hcd/hardware state ... nuking all pending urbs and
1036          * cleaning up all state associated with the current configuration
1037          * so that the hardware is now fully quiesced.
1038          */
1039         usb_disable_device(udev, 0);
1040
1041         /* Free the device number, remove the /proc/bus/usb entry and
1042          * the sysfs attributes, and delete the parent's children[]
1043          * (or root_hub) pointer.
1044          */
1045         dev_dbg (&udev->dev, "unregistering device\n");
1046         release_address(udev);
1047         usbfs_remove_device(udev);
1048         usb_remove_sysfs_dev_files(udev);
1049
1050         /* Avoid races with recursively_mark_NOTATTACHED() */
1051         spin_lock_irq(&device_state_lock);
1052         *pdev = NULL;
1053         spin_unlock_irq(&device_state_lock);
1054
1055         if (!udev->parent) {
1056                 usb_unlock_device(udev);
1057                 up(&usb_bus_list_lock);
1058         } else
1059                 up(&udev->serialize);
1060
1061         device_unregister(&udev->dev);
1062 }
1063
1064 static int choose_configuration(struct usb_device *udev)
1065 {
1066         int c, i;
1067
1068         /* NOTE: this should interact with hub power budgeting */
1069
1070         c = udev->config[0].desc.bConfigurationValue;
1071         if (udev->descriptor.bNumConfigurations != 1) {
1072                 for (i = 0; i < udev->descriptor.bNumConfigurations; i++) {
1073                         struct usb_interface_descriptor *desc;
1074
1075                         /* heuristic:  Linux is more likely to have class
1076                          * drivers, so avoid vendor-specific interfaces.
1077                          */
1078                         desc = &udev->config[i].intf_cache[0]
1079                                         ->altsetting->desc;
1080                         if (desc->bInterfaceClass == USB_CLASS_VENDOR_SPEC)
1081                                 continue;
1082                         /* COMM/2/all is CDC ACM, except 0xff is MSFT RNDIS.
1083                          * MSFT needs this to be the first config; never use
1084                          * it as the default unless Linux has host-side RNDIS.
1085                          * A second config would ideally be CDC-Ethernet, but
1086                          * may instead be the "vendor specific" CDC subset
1087                          * long used by ARM Linux for sa1100 or pxa255.
1088                          */
1089                         if (desc->bInterfaceClass == USB_CLASS_COMM
1090                                         && desc->bInterfaceSubClass == 2
1091                                         && desc->bInterfaceProtocol == 0xff) {
1092                                 c = udev->config[1].desc.bConfigurationValue;
1093                                 continue;
1094                         }
1095                         c = udev->config[i].desc.bConfigurationValue;
1096                         break;
1097                 }
1098                 dev_info(&udev->dev,
1099                         "configuration #%d chosen from %d choices\n",
1100                         c, udev->descriptor.bNumConfigurations);
1101         }
1102         return c;
1103 }
1104
1105 #ifdef DEBUG
1106 static void show_string(struct usb_device *udev, char *id, char *string)
1107 {
1108         if (!string)
1109                 return;
1110         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1111 }
1112
1113 #else
1114 static inline void show_string(struct usb_device *udev, char *id, char *string)
1115 {}
1116 #endif
1117
1118 static void get_string(struct usb_device *udev, char **string, int index)
1119 {
1120         char *buf;
1121
1122         if (!index)
1123                 return;
1124         buf = kmalloc(256, GFP_KERNEL);
1125         if (!buf)
1126                 return;
1127         if (usb_string(udev, index, buf, 256) > 0)
1128                 *string = buf;
1129         else
1130                 kfree(buf);
1131 }
1132
1133
1134 #ifdef  CONFIG_USB_OTG
1135 #include "otg_whitelist.h"
1136 #endif
1137
1138 /**
1139  * usb_new_device - perform initial device setup (usbcore-internal)
1140  * @udev: newly addressed device (in ADDRESS state)
1141  *
1142  * This is called with devices which have been enumerated, but not yet
1143  * configured.  The device descriptor is available, but not descriptors
1144  * for any device configuration.  The caller must have locked udev and
1145  * either the parent hub (if udev is a normal device) or else the
1146  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1147  * udev has already been installed, but udev is not yet visible through
1148  * sysfs or other filesystem code.
1149  *
1150  * Returns 0 for success (device is configured and listed, with its
1151  * interfaces, in sysfs); else a negative errno value.
1152  *
1153  * This call is synchronous, and may not be used in an interrupt context.
1154  *
1155  * Only the hub driver should ever call this; root hub registration
1156  * uses it indirectly.
1157  */
1158 int usb_new_device(struct usb_device *udev)
1159 {
1160         int err;
1161         int c;
1162
1163         err = usb_get_configuration(udev);
1164         if (err < 0) {
1165                 dev_err(&udev->dev, "can't read configurations, error %d\n",
1166                         err);
1167                 goto fail;
1168         }
1169
1170         /* read the standard strings and cache them if present */
1171         get_string(udev, &udev->product, udev->descriptor.iProduct);
1172         get_string(udev, &udev->manufacturer, udev->descriptor.iManufacturer);
1173         get_string(udev, &udev->serial, udev->descriptor.iSerialNumber);
1174
1175         /* Tell the world! */
1176         dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1177                         "SerialNumber=%d\n",
1178                         udev->descriptor.iManufacturer,
1179                         udev->descriptor.iProduct,
1180                         udev->descriptor.iSerialNumber);
1181         show_string(udev, "Product", udev->product);
1182         show_string(udev, "Manufacturer", udev->manufacturer);
1183         show_string(udev, "SerialNumber", udev->serial);
1184
1185 #ifdef  CONFIG_USB_OTG
1186         /*
1187          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1188          * to wake us after we've powered off VBUS; and HNP, switching roles
1189          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1190          */
1191         if (!udev->bus->is_b_host
1192                         && udev->config
1193                         && udev->parent == udev->bus->root_hub) {
1194                 struct usb_otg_descriptor       *desc = 0;
1195                 struct usb_bus                  *bus = udev->bus;
1196
1197                 /* descriptor may appear anywhere in config */
1198                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1199                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1200                                         USB_DT_OTG, (void **) &desc) == 0) {
1201                         if (desc->bmAttributes & USB_OTG_HNP) {
1202                                 unsigned                port1;
1203                                 struct usb_device       *root = udev->parent;
1204
1205                                 for (port1 = 1; port1 <= root->maxchild;
1206                                                 port1++) {
1207                                         if (root->children[port1-1] == udev)
1208                                                 break;
1209                                 }
1210
1211                                 dev_info(&udev->dev,
1212                                         "Dual-Role OTG device on %sHNP port\n",
1213                                         (port1 == bus->otg_port)
1214                                                 ? "" : "non-");
1215
1216                                 /* enable HNP before suspend, it's simpler */
1217                                 if (port1 == bus->otg_port)
1218                                         bus->b_hnp_enable = 1;
1219                                 err = usb_control_msg(udev,
1220                                         usb_sndctrlpipe(udev, 0),
1221                                         USB_REQ_SET_FEATURE, 0,
1222                                         bus->b_hnp_enable
1223                                                 ? USB_DEVICE_B_HNP_ENABLE
1224                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1225                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1226                                 if (err < 0) {
1227                                         /* OTG MESSAGE: report errors here,
1228                                          * customize to match your product.
1229                                          */
1230                                         dev_info(&udev->dev,
1231                                                 "can't set HNP mode; %d\n",
1232                                                 err);
1233                                         bus->b_hnp_enable = 0;
1234                                 }
1235                         }
1236                 }
1237         }
1238
1239         if (!is_targeted(udev)) {
1240
1241                 /* Maybe it can talk to us, though we can't talk to it.
1242                  * (Includes HNP test device.)
1243                  */
1244                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1245                         static int __usb_suspend_device (struct usb_device *,
1246                                                 int port1, pm_message_t state);
1247                         err = __usb_suspend_device(udev,
1248                                         udev->bus->otg_port,
1249                                         PMSG_SUSPEND);
1250                         if (err < 0)
1251                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1252                 }
1253                 err = -ENODEV;
1254                 goto fail;
1255         }
1256 #endif
1257
1258         /* put device-specific files into sysfs */
1259         err = device_add (&udev->dev);
1260         if (err) {
1261                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1262                 goto fail;
1263         }
1264         usb_create_sysfs_dev_files (udev);
1265
1266         /* choose and set the configuration. that registers the interfaces
1267          * with the driver core, and lets usb device drivers bind to them.
1268          */
1269         c = choose_configuration(udev);
1270         if (c < 0)
1271                 dev_warn(&udev->dev,
1272                                 "can't choose an initial configuration\n");
1273         else {
1274                 err = usb_set_configuration(udev, c);
1275                 if (err) {
1276                         dev_err(&udev->dev, "can't set config #%d, error %d\n",
1277                                         c, err);
1278                         usb_remove_sysfs_dev_files(udev);
1279                         device_del(&udev->dev);
1280                         goto fail;
1281                 }
1282         }
1283
1284         /* USB device state == configured ... usable */
1285
1286         /* add a /proc/bus/usb entry */
1287         usbfs_add_device(udev);
1288         return 0;
1289
1290 fail:
1291         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1292         return err;
1293 }
1294
1295
1296 static int hub_port_status(struct usb_hub *hub, int port1,
1297                                u16 *status, u16 *change)
1298 {
1299         int ret;
1300
1301         ret = get_port_status(hub->hdev, port1, &hub->status->port);
1302         if (ret < 0)
1303                 dev_err (hub->intfdev,
1304                         "%s failed (err = %d)\n", __FUNCTION__, ret);
1305         else {
1306                 *status = le16_to_cpu(hub->status->port.wPortStatus);
1307                 *change = le16_to_cpu(hub->status->port.wPortChange);
1308                 ret = 0;
1309         }
1310         return ret;
1311 }
1312
1313 #define PORT_RESET_TRIES        5
1314 #define SET_ADDRESS_TRIES       2
1315 #define GET_DESCRIPTOR_TRIES    2
1316 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1317 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1318
1319 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1320 #define HUB_SHORT_RESET_TIME    10
1321 #define HUB_LONG_RESET_TIME     200
1322 #define HUB_RESET_TIMEOUT       500
1323
1324 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1325                                 struct usb_device *udev, unsigned int delay)
1326 {
1327         int delay_time, ret;
1328         u16 portstatus;
1329         u16 portchange;
1330
1331         for (delay_time = 0;
1332                         delay_time < HUB_RESET_TIMEOUT;
1333                         delay_time += delay) {
1334                 /* wait to give the device a chance to reset */
1335                 msleep(delay);
1336
1337                 /* read and decode port status */
1338                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1339                 if (ret < 0)
1340                         return ret;
1341
1342                 /* Device went away? */
1343                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1344                         return -ENOTCONN;
1345
1346                 /* bomb out completely if something weird happened */
1347                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1348                         return -EINVAL;
1349
1350                 /* if we`ve finished resetting, then break out of the loop */
1351                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1352                     (portstatus & USB_PORT_STAT_ENABLE)) {
1353                         if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1354                                 udev->speed = USB_SPEED_HIGH;
1355                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1356                                 udev->speed = USB_SPEED_LOW;
1357                         else
1358                                 udev->speed = USB_SPEED_FULL;
1359                         return 0;
1360                 }
1361
1362                 /* switch to the long delay after two short delay failures */
1363                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1364                         delay = HUB_LONG_RESET_TIME;
1365
1366                 dev_dbg (hub->intfdev,
1367                         "port %d not reset yet, waiting %dms\n",
1368                         port1, delay);
1369         }
1370
1371         return -EBUSY;
1372 }
1373
1374 static int hub_port_reset(struct usb_hub *hub, int port1,
1375                                 struct usb_device *udev, unsigned int delay)
1376 {
1377         int i, status;
1378
1379         /* Reset the port */
1380         for (i = 0; i < PORT_RESET_TRIES; i++) {
1381                 status = set_port_feature(hub->hdev,
1382                                 port1, USB_PORT_FEAT_RESET);
1383                 if (status)
1384                         dev_err(hub->intfdev,
1385                                         "cannot reset port %d (err = %d)\n",
1386                                         port1, status);
1387                 else {
1388                         status = hub_port_wait_reset(hub, port1, udev, delay);
1389                         if (status)
1390                                 dev_dbg(hub->intfdev,
1391                                                 "port_wait_reset: err = %d\n",
1392                                                 status);
1393                 }
1394
1395                 /* return on disconnect or reset */
1396                 switch (status) {
1397                 case 0:
1398                         /* TRSTRCY = 10 ms */
1399                         msleep(10);
1400                         /* FALL THROUGH */
1401                 case -ENOTCONN:
1402                 case -ENODEV:
1403                         clear_port_feature(hub->hdev,
1404                                 port1, USB_PORT_FEAT_C_RESET);
1405                         /* FIXME need disconnect() for NOTATTACHED device */
1406                         usb_set_device_state(udev, status
1407                                         ? USB_STATE_NOTATTACHED
1408                                         : USB_STATE_DEFAULT);
1409                         return status;
1410                 }
1411
1412                 dev_dbg (hub->intfdev,
1413                         "port %d not enabled, trying reset again...\n",
1414                         port1);
1415                 delay = HUB_LONG_RESET_TIME;
1416         }
1417
1418         dev_err (hub->intfdev,
1419                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1420                 port1);
1421
1422         return status;
1423 }
1424
1425 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
1426 {
1427         struct usb_device *hdev = hub->hdev;
1428         int ret;
1429
1430         if (hdev->children[port1-1] && set_state) {
1431                 usb_set_device_state(hdev->children[port1-1],
1432                                 USB_STATE_NOTATTACHED);
1433         }
1434         ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
1435         if (ret)
1436                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
1437                         port1, ret);
1438
1439         return ret;
1440 }
1441
1442 /*
1443  * Disable a port and mark a logical connnect-change event, so that some
1444  * time later khubd will disconnect() any existing usb_device on the port
1445  * and will re-enumerate if there actually is a device attached.
1446  */
1447 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1448 {
1449         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1450         hub_port_disable(hub, port1, 1);
1451
1452         /* FIXME let caller ask to power down the port:
1453          *  - some devices won't enumerate without a VBUS power cycle
1454          *  - SRP saves power that way
1455          *  - usb_suspend_device(dev, PMSG_SUSPEND)
1456          * That's easy if this hub can switch power per-port, and
1457          * khubd reactivates the port later (timer, SRP, etc).
1458          * Powerdown must be optional, because of reset/DFU.
1459          */
1460
1461         set_bit(port1, hub->change_bits);
1462         kick_khubd(hub);
1463 }
1464
1465
1466 #ifdef  CONFIG_USB_SUSPEND
1467
1468 /*
1469  * Selective port suspend reduces power; most suspended devices draw
1470  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1471  * All devices below the suspended port are also suspended.
1472  *
1473  * Devices leave suspend state when the host wakes them up.  Some devices
1474  * also support "remote wakeup", where the device can activate the USB
1475  * tree above them to deliver data, such as a keypress or packet.  In
1476  * some cases, this wakes the USB host.
1477  */
1478 static int hub_port_suspend(struct usb_hub *hub, int port1,
1479                 struct usb_device *udev)
1480 {
1481         int     status;
1482
1483         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1484
1485         /* enable remote wakeup when appropriate; this lets the device
1486          * wake up the upstream hub (including maybe the root hub).
1487          *
1488          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1489          * we don't explicitly enable it here.
1490          */
1491         if (udev->actconfig
1492                         // && FIXME (remote wakeup enabled on this bus)
1493                         // ... currently assuming it's always appropriate
1494                         && (udev->actconfig->desc.bmAttributes
1495                                 & USB_CONFIG_ATT_WAKEUP) != 0) {
1496                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1497                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1498                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1499                                 NULL, 0,
1500                                 USB_CTRL_SET_TIMEOUT);
1501                 if (status)
1502                         dev_dbg(&udev->dev,
1503                                 "won't remote wakeup, status %d\n",
1504                                 status);
1505         }
1506
1507         /* see 7.1.7.6 */
1508         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1509         if (status) {
1510                 dev_dbg(hub->intfdev,
1511                         "can't suspend port %d, status %d\n",
1512                         port1, status);
1513                 /* paranoia:  "should not happen" */
1514                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1515                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1516                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1517                                 NULL, 0,
1518                                 USB_CTRL_SET_TIMEOUT);
1519         } else {
1520                 /* device has up to 10 msec to fully suspend */
1521                 dev_dbg(&udev->dev, "usb suspend\n");
1522                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1523                 msleep(10);
1524         }
1525         return status;
1526 }
1527
1528 /*
1529  * Devices on USB hub ports have only one "suspend" state, corresponding
1530  * to ACPI D2, "may cause the device to lose some context".
1531  * State transitions include:
1532  *
1533  *   - suspend, resume ... when the VBUS power link stays live
1534  *   - suspend, disconnect ... VBUS lost
1535  *
1536  * Once VBUS drop breaks the circuit, the port it's using has to go through
1537  * normal re-enumeration procedures, starting with enabling VBUS power.
1538  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1539  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1540  * timer, no SRP, no requests through sysfs.
1541  */
1542 static int __usb_suspend_device (struct usb_device *udev, int port1,
1543                                  pm_message_t state)
1544 {
1545         int     status;
1546
1547         /* caller owns the udev device lock */
1548         if (port1 < 0)
1549                 return port1;
1550
1551         if (udev->state == USB_STATE_SUSPENDED
1552                         || udev->state == USB_STATE_NOTATTACHED) {
1553                 return 0;
1554         }
1555
1556         /* suspend interface drivers; if this is a hub, it
1557          * suspends the child devices
1558          */
1559         if (udev->actconfig) {
1560                 int     i;
1561
1562                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1563                         struct usb_interface    *intf;
1564                         struct usb_driver       *driver;
1565
1566                         intf = udev->actconfig->interface[i];
1567                         if (state <= intf->dev.power.power_state)
1568                                 continue;
1569                         if (!intf->dev.driver)
1570                                 continue;
1571                         driver = to_usb_driver(intf->dev.driver);
1572
1573                         if (driver->suspend) {
1574                                 status = driver->suspend(intf, state);
1575                                 if (intf->dev.power.power_state != state
1576                                                 || status)
1577                                         dev_err(&intf->dev,
1578                                                 "suspend %d fail, code %d\n",
1579                                                 state, status);
1580                         }
1581
1582                         /* only drivers with suspend() can ever resume();
1583                          * and after power loss, even they won't.
1584                          * bus_rescan_devices() can rebind drivers later.
1585                          *
1586                          * FIXME the PM core self-deadlocks when unbinding
1587                          * drivers during suspend/resume ... everything grabs
1588                          * dpm_sem (not a spinlock, ugh).  we want to unbind,
1589                          * since we know every driver's probe/disconnect works
1590                          * even for drivers that can't suspend.
1591                          */
1592                         if (!driver->suspend || state > PM_SUSPEND_MEM) {
1593 #if 1
1594                                 dev_warn(&intf->dev, "resume is unsafe!\n");
1595 #else
1596                                 down_write(&usb_bus_type.rwsem);
1597                                 device_release_driver(&intf->dev);
1598                                 up_write(&usb_bus_type.rwsem);
1599 #endif
1600                         }
1601                 }
1602         }
1603
1604         /*
1605          * FIXME this needs port power off call paths too, to help force
1606          * USB into the "generic" PM model.  At least for devices on
1607          * ports that aren't using ganged switching (usually root hubs).
1608          *
1609          * NOTE: SRP-capable links should adopt more aggressive poweroff
1610          * policies (when HNP doesn't apply) once we have mechanisms to
1611          * turn power back on!  (Likely not before 2.7...)
1612          */
1613         if (state > PM_SUSPEND_MEM) {
1614                 dev_warn(&udev->dev, "no poweroff yet, suspending instead\n");
1615         }
1616
1617         /* "global suspend" of the HC-to-USB interface (root hub), or
1618          * "selective suspend" of just one hub-device link.
1619          */
1620         if (!udev->parent) {
1621                 struct usb_bus  *bus = udev->bus;
1622                 if (bus && bus->op->hub_suspend) {
1623                         status = bus->op->hub_suspend (bus);
1624                         if (status == 0) {
1625                                 dev_dbg(&udev->dev, "usb suspend\n");
1626                                 usb_set_device_state(udev,
1627                                                 USB_STATE_SUSPENDED);
1628                         }
1629                 } else
1630                         status = -EOPNOTSUPP;
1631         } else
1632                 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1633                                 udev);
1634
1635         if (status == 0)
1636                 udev->dev.power.power_state = state;
1637         return status;
1638 }
1639
1640 /**
1641  * usb_suspend_device - suspend a usb device
1642  * @udev: device that's no longer in active use
1643  * @state: PMSG_SUSPEND to suspend
1644  * Context: must be able to sleep; device not locked
1645  *
1646  * Suspends a USB device that isn't in active use, conserving power.
1647  * Devices may wake out of a suspend, if anything important happens,
1648  * using the remote wakeup mechanism.  They may also be taken out of
1649  * suspend by the host, using usb_resume_device().  It's also routine
1650  * to disconnect devices while they are suspended.
1651  *
1652  * Suspending OTG devices may trigger HNP, if that's been enabled
1653  * between a pair of dual-role devices.  That will change roles, such
1654  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1655  *
1656  * Returns 0 on success, else negative errno.
1657  */
1658 int usb_suspend_device(struct usb_device *udev, pm_message_t state)
1659 {
1660         int     port1, status;
1661
1662         port1 = locktree(udev);
1663         if (port1 < 0)
1664                 return port1;
1665
1666         status = __usb_suspend_device(udev, port1, state);
1667         usb_unlock_device(udev);
1668         return status;
1669 }
1670
1671 /*
1672  * hardware resume signaling is finished, either because of selective
1673  * resume (by host) or remote wakeup (by device) ... now see what changed
1674  * in the tree that's rooted at this device.
1675  */
1676 static int finish_port_resume(struct usb_device *udev)
1677 {
1678         int     status;
1679         u16     devstatus;
1680
1681         /* caller owns the udev device lock */
1682         dev_dbg(&udev->dev, "usb resume\n");
1683
1684         /* usb ch9 identifies four variants of SUSPENDED, based on what
1685          * state the device resumes to.  Linux currently won't see the
1686          * first two on the host side; they'd be inside hub_port_init()
1687          * during many timeouts, but khubd can't suspend until later.
1688          */
1689         usb_set_device_state(udev, udev->actconfig
1690                         ? USB_STATE_CONFIGURED
1691                         : USB_STATE_ADDRESS);
1692         udev->dev.power.power_state = PMSG_ON;
1693
1694         /* 10.5.4.5 says be sure devices in the tree are still there.
1695          * For now let's assume the device didn't go crazy on resume,
1696          * and device drivers will know about any resume quirks.
1697          */
1698         status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1699         if (status < 0)
1700                 dev_dbg(&udev->dev,
1701                         "gone after usb resume? status %d\n",
1702                         status);
1703         else if (udev->actconfig) {
1704                 unsigned        i;
1705
1706                 le16_to_cpus(&devstatus);
1707                 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
1708                         status = usb_control_msg(udev,
1709                                         usb_sndctrlpipe(udev, 0),
1710                                         USB_REQ_CLEAR_FEATURE,
1711                                                 USB_RECIP_DEVICE,
1712                                         USB_DEVICE_REMOTE_WAKEUP, 0,
1713                                         NULL, 0,
1714                                         USB_CTRL_SET_TIMEOUT);
1715                         if (status) {
1716                                 dev_dbg(&udev->dev, "disable remote "
1717                                         "wakeup, status %d\n", status);
1718                                 status = 0;
1719                         }
1720                 }
1721
1722                 /* resume interface drivers; if this is a hub, it
1723                  * resumes the child devices
1724                  */
1725                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1726                         struct usb_interface    *intf;
1727                         struct usb_driver       *driver;
1728
1729                         intf = udev->actconfig->interface[i];
1730                         if (intf->dev.power.power_state == PMSG_SUSPEND)
1731                                 continue;
1732                         if (!intf->dev.driver) {
1733                                 /* FIXME maybe force to alt 0 */
1734                                 continue;
1735                         }
1736                         driver = to_usb_driver(intf->dev.driver);
1737
1738                         /* bus_rescan_devices() may rebind drivers */
1739                         if (!driver->resume)
1740                                 continue;
1741
1742                         /* can we do better than just logging errors? */
1743                         status = driver->resume(intf);
1744                         if (intf->dev.power.power_state != PMSG_ON
1745                                         || status)
1746                                 dev_dbg(&intf->dev,
1747                                         "resume fail, state %d code %d\n",
1748                                         intf->dev.power.power_state, status);
1749                 }
1750                 status = 0;
1751
1752         } else if (udev->devnum <= 0) {
1753                 dev_dbg(&udev->dev, "bogus resume!\n");
1754                 status = -EINVAL;
1755         }
1756         return status;
1757 }
1758
1759 static int
1760 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1761 {
1762         int     status;
1763
1764         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1765
1766         /* see 7.1.7.7; affects power usage, but not budgeting */
1767         status = clear_port_feature(hub->hdev,
1768                         port1, USB_PORT_FEAT_SUSPEND);
1769         if (status) {
1770                 dev_dbg(hub->intfdev,
1771                         "can't resume port %d, status %d\n",
1772                         port1, status);
1773         } else {
1774                 u16             devstatus;
1775                 u16             portchange;
1776
1777                 /* drive resume for at least 20 msec */
1778                 if (udev)
1779                         dev_dbg(&udev->dev, "RESUME\n");
1780                 msleep(25);
1781
1782 #define LIVE_FLAGS      ( USB_PORT_STAT_POWER \
1783                         | USB_PORT_STAT_ENABLE \
1784                         | USB_PORT_STAT_CONNECTION)
1785
1786                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1787                  * stop resume signaling.  Then finish the resume
1788                  * sequence.
1789                  */
1790                 devstatus = portchange = 0;
1791                 status = hub_port_status(hub, port1,
1792                                 &devstatus, &portchange);
1793                 if (status < 0
1794                                 || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
1795                                 || (devstatus & USB_PORT_STAT_SUSPEND) != 0
1796                                 ) {
1797                         dev_dbg(hub->intfdev,
1798                                 "port %d status %04x.%04x after resume, %d\n",
1799                                 port1, portchange, devstatus, status);
1800                 } else {
1801                         /* TRSMRCY = 10 msec */
1802                         msleep(10);
1803                         if (udev)
1804                                 status = finish_port_resume(udev);
1805                 }
1806         }
1807         if (status < 0)
1808                 hub_port_logical_disconnect(hub, port1);
1809
1810         return status;
1811 }
1812
1813 static int hub_resume (struct usb_interface *intf);
1814
1815 /**
1816  * usb_resume_device - re-activate a suspended usb device
1817  * @udev: device to re-activate
1818  * Context: must be able to sleep; device not locked
1819  *
1820  * This will re-activate the suspended device, increasing power usage
1821  * while letting drivers communicate again with its endpoints.
1822  * USB resume explicitly guarantees that the power session between
1823  * the host and the device is the same as it was when the device
1824  * suspended.
1825  *
1826  * Returns 0 on success, else negative errno.
1827  */
1828 int usb_resume_device(struct usb_device *udev)
1829 {
1830         int     port1, status;
1831
1832         port1 = locktree(udev);
1833         if (port1 < 0)
1834                 return port1;
1835
1836         /* "global resume" of the HC-to-USB interface (root hub), or
1837          * selective resume of one hub-to-device port
1838          */
1839         if (!udev->parent) {
1840                 struct usb_bus  *bus = udev->bus;
1841                 if (bus && bus->op->hub_resume) {
1842                         status = bus->op->hub_resume (bus);
1843                 } else
1844                         status = -EOPNOTSUPP;
1845                 if (status == 0) {
1846                         dev_dbg(&udev->dev, "usb resume\n");
1847                         /* TRSMRCY = 10 msec */
1848                         msleep(10);
1849                         usb_set_device_state (udev, USB_STATE_CONFIGURED);
1850                         udev->dev.power.power_state = PMSG_ON;
1851                         status = hub_resume (udev
1852                                         ->actconfig->interface[0]);
1853                 }
1854         } else if (udev->state == USB_STATE_SUSPENDED) {
1855                 // NOTE this fails if parent is also suspended...
1856                 status = hub_port_resume(hdev_to_hub(udev->parent),
1857                                 port1, udev);
1858         } else {
1859                 status = 0;
1860         }
1861         if (status < 0) {
1862                 dev_dbg(&udev->dev, "can't resume, status %d\n",
1863                         status);
1864         }
1865
1866         usb_unlock_device(udev);
1867
1868         /* rebind drivers that had no suspend() */
1869         if (status == 0) {
1870                 usb_lock_all_devices();
1871                 bus_rescan_devices(&usb_bus_type);
1872                 usb_unlock_all_devices();
1873         }
1874         return status;
1875 }
1876
1877 static int remote_wakeup(struct usb_device *udev)
1878 {
1879         int     status = 0;
1880
1881         /* don't repeat RESUME sequence if this device
1882          * was already woken up by some other task
1883          */
1884         down(&udev->serialize);
1885         if (udev->state == USB_STATE_SUSPENDED) {
1886                 dev_dbg(&udev->dev, "RESUME (wakeup)\n");
1887                 /* TRSMRCY = 10 msec */
1888                 msleep(10);
1889                 status = finish_port_resume(udev);
1890         }
1891         up(&udev->serialize);
1892         return status;
1893 }
1894
1895 static int hub_suspend(struct usb_interface *intf, pm_message_t state)
1896 {
1897         struct usb_hub          *hub = usb_get_intfdata (intf);
1898         struct usb_device       *hdev = hub->hdev;
1899         unsigned                port1;
1900         int                     status;
1901
1902         /* stop khubd and related activity */
1903         hub_quiesce(hub);
1904
1905         /* then suspend every port */
1906         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1907                 struct usb_device       *udev;
1908
1909                 udev = hdev->children [port1-1];
1910                 if (!udev)
1911                         continue;
1912                 down(&udev->serialize);
1913                 status = __usb_suspend_device(udev, port1, state);
1914                 up(&udev->serialize);
1915                 if (status < 0)
1916                         dev_dbg(&intf->dev, "suspend port %d --> %d\n",
1917                                 port1, status);
1918         }
1919
1920         intf->dev.power.power_state = state;
1921         return 0;
1922 }
1923
1924 static int hub_resume(struct usb_interface *intf)
1925 {
1926         struct usb_device       *hdev = interface_to_usbdev(intf);
1927         struct usb_hub          *hub = usb_get_intfdata (intf);
1928         unsigned                port1;
1929         int                     status;
1930
1931         if (intf->dev.power.power_state == PM_SUSPEND_ON)
1932                 return 0;
1933
1934         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1935                 struct usb_device       *udev;
1936                 u16                     portstat, portchange;
1937
1938                 udev = hdev->children [port1-1];
1939                 status = hub_port_status(hub, port1, &portstat, &portchange);
1940                 if (status == 0) {
1941                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
1942                                 clear_port_feature(hdev, port1,
1943                                         USB_PORT_FEAT_C_SUSPEND);
1944                                 portchange &= ~USB_PORT_STAT_C_SUSPEND;
1945                         }
1946
1947                         /* let khubd handle disconnects etc */
1948                         if (portchange)
1949                                 continue;
1950                 }
1951
1952                 if (!udev || status < 0)
1953                         continue;
1954                 down (&udev->serialize);
1955                 if (portstat & USB_PORT_STAT_SUSPEND)
1956                         status = hub_port_resume(hub, port1, udev);
1957                 else {
1958                         status = finish_port_resume(udev);
1959                         if (status < 0) {
1960                                 dev_dbg(&intf->dev, "resume port %d --> %d\n",
1961                                         port1, status);
1962                                 hub_port_logical_disconnect(hub, port1);
1963                         }
1964                 }
1965                 up(&udev->serialize);
1966         }
1967         intf->dev.power.power_state = PMSG_ON;
1968
1969         hub->resume_root_hub = 0;
1970         hub_activate(hub);
1971         return 0;
1972 }
1973
1974 void usb_resume_root_hub(struct usb_device *hdev)
1975 {
1976         struct usb_hub *hub = hdev_to_hub(hdev);
1977
1978         hub->resume_root_hub = 1;
1979         kick_khubd(hub);
1980 }
1981
1982 #else   /* !CONFIG_USB_SUSPEND */
1983
1984 int usb_suspend_device(struct usb_device *udev, pm_message_t state)
1985 {
1986         return 0;
1987 }
1988
1989 int usb_resume_device(struct usb_device *udev)
1990 {
1991         return 0;
1992 }
1993
1994 #define hub_suspend             NULL
1995 #define hub_resume              NULL
1996 #define remote_wakeup(x)        0
1997
1998 #endif  /* CONFIG_USB_SUSPEND */
1999
2000 EXPORT_SYMBOL(usb_suspend_device);
2001 EXPORT_SYMBOL(usb_resume_device);
2002
2003
2004
2005 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2006  *
2007  * Between connect detection and reset signaling there must be a delay
2008  * of 100ms at least for debounce and power-settling.  The corresponding
2009  * timer shall restart whenever the downstream port detects a disconnect.
2010  *
2011  * Apparently there are some bluetooth and irda-dongles and a number of
2012  * low-speed devices for which this debounce period may last over a second.
2013  * Not covered by the spec - but easy to deal with.
2014  *
2015  * This implementation uses a 1500ms total debounce timeout; if the
2016  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
2017  * every 25ms for transient disconnects.  When the port status has been
2018  * unchanged for 100ms it returns the port status.
2019  */
2020
2021 #define HUB_DEBOUNCE_TIMEOUT    1500
2022 #define HUB_DEBOUNCE_STEP         25
2023 #define HUB_DEBOUNCE_STABLE      100
2024
2025 static int hub_port_debounce(struct usb_hub *hub, int port1)
2026 {
2027         int ret;
2028         int total_time, stable_time = 0;
2029         u16 portchange, portstatus;
2030         unsigned connection = 0xffff;
2031
2032         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2033                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2034                 if (ret < 0)
2035                         return ret;
2036
2037                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2038                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2039                         stable_time += HUB_DEBOUNCE_STEP;
2040                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2041                                 break;
2042                 } else {
2043                         stable_time = 0;
2044                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2045                 }
2046
2047                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2048                         clear_port_feature(hub->hdev, port1,
2049                                         USB_PORT_FEAT_C_CONNECTION);
2050                 }
2051
2052                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2053                         break;
2054                 msleep(HUB_DEBOUNCE_STEP);
2055         }
2056
2057         dev_dbg (hub->intfdev,
2058                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2059                 port1, total_time, stable_time, portstatus);
2060
2061         if (stable_time < HUB_DEBOUNCE_STABLE)
2062                 return -ETIMEDOUT;
2063         return portstatus;
2064 }
2065
2066 static void ep0_reinit(struct usb_device *udev)
2067 {
2068         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2069         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2070         udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2071 }
2072
2073 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2074 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2075
2076 static int hub_set_address(struct usb_device *udev)
2077 {
2078         int retval;
2079
2080         if (udev->devnum == 0)
2081                 return -EINVAL;
2082         if (udev->state == USB_STATE_ADDRESS)
2083                 return 0;
2084         if (udev->state != USB_STATE_DEFAULT)
2085                 return -EINVAL;
2086         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2087                 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2088                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2089         if (retval == 0) {
2090                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2091                 ep0_reinit(udev);
2092         }
2093         return retval;
2094 }
2095
2096 /* Reset device, (re)assign address, get device descriptor.
2097  * Device connection must be stable, no more debouncing needed.
2098  * Returns device in USB_STATE_ADDRESS, except on error.
2099  *
2100  * If this is called for an already-existing device (as part of
2101  * usb_reset_device), the caller must own the device lock.  For a
2102  * newly detected device that is not accessible through any global
2103  * pointers, it's not necessary to lock the device.
2104  */
2105 static int
2106 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2107                 int retry_counter)
2108 {
2109         static DECLARE_MUTEX(usb_address0_sem);
2110
2111         struct usb_device       *hdev = hub->hdev;
2112         int                     i, j, retval;
2113         unsigned                delay = HUB_SHORT_RESET_TIME;
2114         enum usb_device_speed   oldspeed = udev->speed;
2115
2116         /* root hub ports have a slightly longer reset period
2117          * (from USB 2.0 spec, section 7.1.7.5)
2118          */
2119         if (!hdev->parent) {
2120                 delay = HUB_ROOT_RESET_TIME;
2121                 if (port1 == hdev->bus->otg_port)
2122                         hdev->bus->b_hnp_enable = 0;
2123         }
2124
2125         /* Some low speed devices have problems with the quick delay, so */
2126         /*  be a bit pessimistic with those devices. RHbug #23670 */
2127         if (oldspeed == USB_SPEED_LOW)
2128                 delay = HUB_LONG_RESET_TIME;
2129
2130         down(&usb_address0_sem);
2131
2132         /* Reset the device; full speed may morph to high speed */
2133         retval = hub_port_reset(hub, port1, udev, delay);
2134         if (retval < 0)         /* error or disconnect */
2135                 goto fail;
2136                                 /* success, speed is known */
2137         retval = -ENODEV;
2138
2139         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2140                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2141                 goto fail;
2142         }
2143         oldspeed = udev->speed;
2144
2145         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2146          * it's fixed size except for full speed devices.
2147          */
2148         switch (udev->speed) {
2149         case USB_SPEED_HIGH:            /* fixed at 64 */
2150                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2151                 break;
2152         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2153                 /* to determine the ep0 maxpacket size, try to read
2154                  * the device descriptor to get bMaxPacketSize0 and
2155                  * then correct our initial guess.
2156                  */
2157                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2158                 break;
2159         case USB_SPEED_LOW:             /* fixed at 8 */
2160                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2161                 break;
2162         default:
2163                 goto fail;
2164         }
2165
2166         dev_info (&udev->dev,
2167                         "%s %s speed USB device using %s and address %d\n",
2168                         (udev->config) ? "reset" : "new",
2169                         ({ char *speed; switch (udev->speed) {
2170                         case USB_SPEED_LOW:     speed = "low";  break;
2171                         case USB_SPEED_FULL:    speed = "full"; break;
2172                         case USB_SPEED_HIGH:    speed = "high"; break;
2173                         default:                speed = "?";    break;
2174                         }; speed;}),
2175                         udev->bus->controller->driver->name,
2176                         udev->devnum);
2177
2178         /* Set up TT records, if needed  */
2179         if (hdev->tt) {
2180                 udev->tt = hdev->tt;
2181                 udev->ttport = hdev->ttport;
2182         } else if (udev->speed != USB_SPEED_HIGH
2183                         && hdev->speed == USB_SPEED_HIGH) {
2184                 udev->tt = &hub->tt;
2185                 udev->ttport = port1;
2186         }
2187
2188         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2189          * Because device hardware and firmware is sometimes buggy in
2190          * this area, and this is how Linux has done it for ages.
2191          * Change it cautiously.
2192          *
2193          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2194          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2195          * so it may help with some non-standards-compliant devices.
2196          * Otherwise we start with SET_ADDRESS and then try to read the
2197          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2198          * value.
2199          */
2200         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2201                 if (USE_NEW_SCHEME(retry_counter)) {
2202                         struct usb_device_descriptor *buf;
2203                         int r = 0;
2204
2205 #define GET_DESCRIPTOR_BUFSIZE  64
2206                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2207                         if (!buf) {
2208                                 retval = -ENOMEM;
2209                                 continue;
2210                         }
2211
2212                         /* Use a short timeout the first time through,
2213                          * so that recalcitrant full-speed devices with
2214                          * 8- or 16-byte ep0-maxpackets won't slow things
2215                          * down tremendously by NAKing the unexpectedly
2216                          * early status stage.  Also, retry on all errors;
2217                          * some devices are flakey.
2218                          */
2219                         for (j = 0; j < 3; ++j) {
2220                                 buf->bMaxPacketSize0 = 0;
2221                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2222                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2223                                         USB_DT_DEVICE << 8, 0,
2224                                         buf, GET_DESCRIPTOR_BUFSIZE,
2225                                         (i ? USB_CTRL_GET_TIMEOUT : 1000));
2226                                 switch (buf->bMaxPacketSize0) {
2227                                 case 8: case 16: case 32: case 64:
2228                                         if (buf->bDescriptorType ==
2229                                                         USB_DT_DEVICE) {
2230                                                 r = 0;
2231                                                 break;
2232                                         }
2233                                         /* FALL THROUGH */
2234                                 default:
2235                                         if (r == 0)
2236                                                 r = -EPROTO;
2237                                         break;
2238                                 }
2239                                 if (r == 0)
2240                                         break;
2241                         }
2242                         udev->descriptor.bMaxPacketSize0 =
2243                                         buf->bMaxPacketSize0;
2244                         kfree(buf);
2245
2246                         retval = hub_port_reset(hub, port1, udev, delay);
2247                         if (retval < 0)         /* error or disconnect */
2248                                 goto fail;
2249                         if (oldspeed != udev->speed) {
2250                                 dev_dbg(&udev->dev,
2251                                         "device reset changed speed!\n");
2252                                 retval = -ENODEV;
2253                                 goto fail;
2254                         }
2255                         if (r) {
2256                                 dev_err(&udev->dev, "device descriptor "
2257                                                 "read/%s, error %d\n",
2258                                                 "64", r);
2259                                 retval = -EMSGSIZE;
2260                                 continue;
2261                         }
2262 #undef GET_DESCRIPTOR_BUFSIZE
2263                 }
2264
2265                 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2266                         retval = hub_set_address(udev);
2267                         if (retval >= 0)
2268                                 break;
2269                         msleep(200);
2270                 }
2271                 if (retval < 0) {
2272                         dev_err(&udev->dev,
2273                                 "device not accepting address %d, error %d\n",
2274                                 udev->devnum, retval);
2275                         goto fail;
2276                 }
2277
2278                 /* cope with hardware quirkiness:
2279                  *  - let SET_ADDRESS settle, some device hardware wants it
2280                  *  - read ep0 maxpacket even for high and low speed,
2281                  */
2282                 msleep(10);
2283                 if (USE_NEW_SCHEME(retry_counter))
2284                         break;
2285
2286                 retval = usb_get_device_descriptor(udev, 8);
2287                 if (retval < 8) {
2288                         dev_err(&udev->dev, "device descriptor "
2289                                         "read/%s, error %d\n",
2290                                         "8", retval);
2291                         if (retval >= 0)
2292                                 retval = -EMSGSIZE;
2293                 } else {
2294                         retval = 0;
2295                         break;
2296                 }
2297         }
2298         if (retval)
2299                 goto fail;
2300
2301         i = udev->descriptor.bMaxPacketSize0;
2302         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2303                 if (udev->speed != USB_SPEED_FULL ||
2304                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2305                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2306                         retval = -EMSGSIZE;
2307                         goto fail;
2308                 }
2309                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2310                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2311                 ep0_reinit(udev);
2312         }
2313
2314         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2315         if (retval < (signed)sizeof(udev->descriptor)) {
2316                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2317                         "all", retval);
2318                 if (retval >= 0)
2319                         retval = -ENOMSG;
2320                 goto fail;
2321         }
2322
2323         retval = 0;
2324
2325 fail:
2326         if (retval)
2327                 hub_port_disable(hub, port1, 0);
2328         up(&usb_address0_sem);
2329         return retval;
2330 }
2331
2332 static void
2333 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2334 {
2335         struct usb_qualifier_descriptor *qual;
2336         int                             status;
2337
2338         qual = kmalloc (sizeof *qual, SLAB_KERNEL);
2339         if (qual == NULL)
2340                 return;
2341
2342         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2343                         qual, sizeof *qual);
2344         if (status == sizeof *qual) {
2345                 dev_info(&udev->dev, "not running at top speed; "
2346                         "connect to a high speed hub\n");
2347                 /* hub LEDs are probably harder to miss than syslog */
2348                 if (hub->has_indicators) {
2349                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2350                         schedule_work (&hub->leds);
2351                 }
2352         }
2353         kfree(qual);
2354 }
2355
2356 static unsigned
2357 hub_power_remaining (struct usb_hub *hub)
2358 {
2359         struct usb_device *hdev = hub->hdev;
2360         int remaining;
2361         unsigned i;
2362
2363         remaining = hub->power_budget;
2364         if (!remaining)         /* self-powered */
2365                 return 0;
2366
2367         for (i = 0; i < hdev->maxchild; i++) {
2368                 struct usb_device       *udev = hdev->children[i];
2369                 int                     delta, ceiling;
2370
2371                 if (!udev)
2372                         continue;
2373
2374                 /* 100mA per-port ceiling, or 8mA for OTG ports */
2375                 if (i != (udev->bus->otg_port - 1) || hdev->parent)
2376                         ceiling = 50;
2377                 else
2378                         ceiling = 4;
2379
2380                 if (udev->actconfig)
2381                         delta = udev->actconfig->desc.bMaxPower;
2382                 else
2383                         delta = ceiling;
2384                 // dev_dbg(&udev->dev, "budgeted %dmA\n", 2 * delta);
2385                 if (delta > ceiling)
2386                         dev_warn(&udev->dev, "%dmA over %dmA budget!\n",
2387                                 2 * (delta - ceiling), 2 * ceiling);
2388                 remaining -= delta;
2389         }
2390         if (remaining < 0) {
2391                 dev_warn(hub->intfdev,
2392                         "%dmA over power budget!\n",
2393                         -2 * remaining);
2394                 remaining = 0;
2395         }
2396         return remaining;
2397 }
2398
2399 /* Handle physical or logical connection change events.
2400  * This routine is called when:
2401  *      a port connection-change occurs;
2402  *      a port enable-change occurs (often caused by EMI);
2403  *      usb_reset_device() encounters changed descriptors (as from
2404  *              a firmware download)
2405  * caller already locked the hub
2406  */
2407 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2408                                         u16 portstatus, u16 portchange)
2409 {
2410         struct usb_device *hdev = hub->hdev;
2411         struct device *hub_dev = hub->intfdev;
2412         int status, i;
2413
2414         dev_dbg (hub_dev,
2415                 "port %d, status %04x, change %04x, %s\n",
2416                 port1, portstatus, portchange, portspeed (portstatus));
2417
2418         if (hub->has_indicators) {
2419                 set_port_led(hub, port1, HUB_LED_AUTO);
2420                 hub->indicator[port1-1] = INDICATOR_AUTO;
2421         }
2422
2423         /* Disconnect any existing devices under this port */
2424         if (hdev->children[port1-1])
2425                 usb_disconnect(&hdev->children[port1-1]);
2426         clear_bit(port1, hub->change_bits);
2427
2428 #ifdef  CONFIG_USB_OTG
2429         /* during HNP, don't repeat the debounce */
2430         if (hdev->bus->is_b_host)
2431                 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2432 #endif
2433
2434         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2435                 status = hub_port_debounce(hub, port1);
2436                 if (status < 0) {
2437                         dev_err (hub_dev,
2438                                 "connect-debounce failed, port %d disabled\n",
2439                                 port1);
2440                         goto done;
2441                 }
2442                 portstatus = status;
2443         }
2444
2445         /* Return now if nothing is connected */
2446         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2447
2448                 /* maybe switch power back on (e.g. root hub was reset) */
2449                 if ((hub->descriptor->wHubCharacteristics
2450                                         & HUB_CHAR_LPSM) < 2
2451                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2452                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2453
2454                 if (portstatus & USB_PORT_STAT_ENABLE)
2455                         goto done;
2456                 return;
2457         }
2458
2459 #ifdef  CONFIG_USB_SUSPEND
2460         /* If something is connected, but the port is suspended, wake it up. */
2461         if (portstatus & USB_PORT_STAT_SUSPEND) {
2462                 status = hub_port_resume(hub, port1, NULL);
2463                 if (status < 0) {
2464                         dev_dbg(hub_dev,
2465                                 "can't clear suspend on port %d; %d\n",
2466                                 port1, status);
2467                         goto done;
2468                 }
2469         }
2470 #endif
2471
2472         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2473                 struct usb_device *udev;
2474
2475                 /* reallocate for each attempt, since references
2476                  * to the previous one can escape in various ways
2477                  */
2478                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2479                 if (!udev) {
2480                         dev_err (hub_dev,
2481                                 "couldn't allocate port %d usb_device\n",
2482                                 port1);
2483                         goto done;
2484                 }
2485
2486                 usb_set_device_state(udev, USB_STATE_POWERED);
2487                 udev->speed = USB_SPEED_UNKNOWN;
2488
2489                 /* set the address */
2490                 choose_address(udev);
2491                 if (udev->devnum <= 0) {
2492                         status = -ENOTCONN;     /* Don't retry */
2493                         goto loop;
2494                 }
2495
2496                 /* reset and get descriptor */
2497                 status = hub_port_init(hub, udev, port1, i);
2498                 if (status < 0)
2499                         goto loop;
2500
2501                 /* consecutive bus-powered hubs aren't reliable; they can
2502                  * violate the voltage drop budget.  if the new child has
2503                  * a "powered" LED, users should notice we didn't enable it
2504                  * (without reading syslog), even without per-port LEDs
2505                  * on the parent.
2506                  */
2507                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2508                                 && hub->power_budget) {
2509                         u16     devstat;
2510
2511                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2512                                         &devstat);
2513                         if (status < 0) {
2514                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2515                                 goto loop_disable;
2516                         }
2517                         cpu_to_le16s(&devstat);
2518                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2519                                 dev_err(&udev->dev,
2520                                         "can't connect bus-powered hub "
2521                                         "to this port\n");
2522                                 if (hub->has_indicators) {
2523                                         hub->indicator[port1-1] =
2524                                                 INDICATOR_AMBER_BLINK;
2525                                         schedule_work (&hub->leds);
2526                                 }
2527                                 status = -ENOTCONN;     /* Don't retry */
2528                                 goto loop_disable;
2529                         }
2530                 }
2531
2532                 /* check for devices running slower than they could */
2533                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2534                                 && udev->speed == USB_SPEED_FULL
2535                                 && highspeed_hubs != 0)
2536                         check_highspeed (hub, udev, port1);
2537
2538                 /* Store the parent's children[] pointer.  At this point
2539                  * udev becomes globally accessible, although presumably
2540                  * no one will look at it until hdev is unlocked.
2541                  */
2542                 down (&udev->serialize);
2543                 status = 0;
2544
2545                 /* We mustn't add new devices if the parent hub has
2546                  * been disconnected; we would race with the
2547                  * recursively_mark_NOTATTACHED() routine.
2548                  */
2549                 spin_lock_irq(&device_state_lock);
2550                 if (hdev->state == USB_STATE_NOTATTACHED)
2551                         status = -ENOTCONN;
2552                 else
2553                         hdev->children[port1-1] = udev;
2554                 spin_unlock_irq(&device_state_lock);
2555
2556                 /* Run it through the hoops (find a driver, etc) */
2557                 if (!status) {
2558                         status = usb_new_device(udev);
2559                         if (status) {
2560                                 spin_lock_irq(&device_state_lock);
2561                                 hdev->children[port1-1] = NULL;
2562                                 spin_unlock_irq(&device_state_lock);
2563                         }
2564                 }
2565
2566                 up (&udev->serialize);
2567                 if (status)
2568                         goto loop_disable;
2569
2570                 status = hub_power_remaining(hub);
2571                 if (status)
2572                         dev_dbg(hub_dev,
2573                                 "%dmA power budget left\n",
2574                                 2 * status);
2575
2576                 return;
2577
2578 loop_disable:
2579                 hub_port_disable(hub, port1, 1);
2580 loop:
2581                 ep0_reinit(udev);
2582                 release_address(udev);
2583                 usb_put_dev(udev);
2584                 if (status == -ENOTCONN)
2585                         break;
2586         }
2587
2588 done:
2589         hub_port_disable(hub, port1, 1);
2590 }
2591
2592 static void hub_events(void)
2593 {
2594         struct list_head *tmp;
2595         struct usb_device *hdev;
2596         struct usb_interface *intf;
2597         struct usb_hub *hub;
2598         struct device *hub_dev;
2599         u16 hubstatus;
2600         u16 hubchange;
2601         u16 portstatus;
2602         u16 portchange;
2603         int i, ret;
2604         int connect_change;
2605
2606         /*
2607          *  We restart the list every time to avoid a deadlock with
2608          * deleting hubs downstream from this one. This should be
2609          * safe since we delete the hub from the event list.
2610          * Not the most efficient, but avoids deadlocks.
2611          */
2612         while (1) {
2613
2614                 /* Grab the first entry at the beginning of the list */
2615                 spin_lock_irq(&hub_event_lock);
2616                 if (list_empty(&hub_event_list)) {
2617                         spin_unlock_irq(&hub_event_lock);
2618                         break;
2619                 }
2620
2621                 tmp = hub_event_list.next;
2622                 list_del_init(tmp);
2623
2624                 hub = list_entry(tmp, struct usb_hub, event_list);
2625                 hdev = hub->hdev;
2626                 intf = to_usb_interface(hub->intfdev);
2627                 hub_dev = &intf->dev;
2628
2629                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
2630                                 hdev->state, hub->descriptor
2631                                         ? hub->descriptor->bNbrPorts
2632                                         : 0,
2633                                 /* NOTE: expects max 15 ports... */
2634                                 (u16) hub->change_bits[0],
2635                                 (u16) hub->event_bits[0]);
2636
2637                 usb_get_intf(intf);
2638                 i = hub->resume_root_hub;
2639                 spin_unlock_irq(&hub_event_lock);
2640
2641                 /* Is this is a root hub wanting to be resumed? */
2642                 if (i)
2643                         usb_resume_device(hdev);
2644
2645                 /* Lock the device, then check to see if we were
2646                  * disconnected while waiting for the lock to succeed. */
2647                 if (locktree(hdev) < 0) {
2648                         usb_put_intf(intf);
2649                         continue;
2650                 }
2651                 if (hub != usb_get_intfdata(intf))
2652                         goto loop;
2653
2654                 /* If the hub has died, clean up after it */
2655                 if (hdev->state == USB_STATE_NOTATTACHED) {
2656                         hub_pre_reset(hub);
2657                         goto loop;
2658                 }
2659
2660                 /* If this is an inactive or suspended hub, do nothing */
2661                 if (hub->quiescing)
2662                         goto loop;
2663
2664                 if (hub->error) {
2665                         dev_dbg (hub_dev, "resetting for error %d\n",
2666                                 hub->error);
2667
2668                         ret = usb_reset_device(hdev);
2669                         if (ret) {
2670                                 dev_dbg (hub_dev,
2671                                         "error resetting hub: %d\n", ret);
2672                                 goto loop;
2673                         }
2674
2675                         hub->nerrors = 0;
2676                         hub->error = 0;
2677                 }
2678
2679                 /* deal with port status changes */
2680                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2681                         if (test_bit(i, hub->busy_bits))
2682                                 continue;
2683                         connect_change = test_bit(i, hub->change_bits);
2684                         if (!test_and_clear_bit(i, hub->event_bits) &&
2685                                         !connect_change && !hub->activating)
2686                                 continue;
2687
2688                         ret = hub_port_status(hub, i,
2689                                         &portstatus, &portchange);
2690                         if (ret < 0)
2691                                 continue;
2692
2693                         if (hub->activating && !hdev->children[i-1] &&
2694                                         (portstatus &
2695                                                 USB_PORT_STAT_CONNECTION))
2696                                 connect_change = 1;
2697
2698                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2699                                 clear_port_feature(hdev, i,
2700                                         USB_PORT_FEAT_C_CONNECTION);
2701                                 connect_change = 1;
2702                         }
2703
2704                         if (portchange & USB_PORT_STAT_C_ENABLE) {
2705                                 if (!connect_change)
2706                                         dev_dbg (hub_dev,
2707                                                 "port %d enable change, "
2708                                                 "status %08x\n",
2709                                                 i, portstatus);
2710                                 clear_port_feature(hdev, i,
2711                                         USB_PORT_FEAT_C_ENABLE);
2712
2713                                 /*
2714                                  * EM interference sometimes causes badly
2715                                  * shielded USB devices to be shutdown by
2716                                  * the hub, this hack enables them again.
2717                                  * Works at least with mouse driver.
2718                                  */
2719                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
2720                                     && !connect_change
2721                                     && hdev->children[i-1]) {
2722                                         dev_err (hub_dev,
2723                                             "port %i "
2724                                             "disabled by hub (EMI?), "
2725                                             "re-enabling...\n",
2726                                                 i);
2727                                         connect_change = 1;
2728                                 }
2729                         }
2730
2731                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2732                                 clear_port_feature(hdev, i,
2733                                         USB_PORT_FEAT_C_SUSPEND);
2734                                 if (hdev->children[i-1]) {
2735                                         ret = remote_wakeup(hdev->
2736                                                         children[i-1]);
2737                                         if (ret < 0)
2738                                                 connect_change = 1;
2739                                 } else {
2740                                         ret = -ENODEV;
2741                                         hub_port_disable(hub, i, 1);
2742                                 }
2743                                 dev_dbg (hub_dev,
2744                                         "resume on port %d, status %d\n",
2745                                         i, ret);
2746                         }
2747
2748                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2749                                 dev_err (hub_dev,
2750                                         "over-current change on port %d\n",
2751                                         i);
2752                                 clear_port_feature(hdev, i,
2753                                         USB_PORT_FEAT_C_OVER_CURRENT);
2754                                 hub_power_on(hub);
2755                         }
2756
2757                         if (portchange & USB_PORT_STAT_C_RESET) {
2758                                 dev_dbg (hub_dev,
2759                                         "reset change on port %d\n",
2760                                         i);
2761                                 clear_port_feature(hdev, i,
2762                                         USB_PORT_FEAT_C_RESET);
2763                         }
2764
2765                         if (connect_change)
2766                                 hub_port_connect_change(hub, i,
2767                                                 portstatus, portchange);
2768                 } /* end for i */
2769
2770                 /* deal with hub status changes */
2771                 if (test_and_clear_bit(0, hub->event_bits) == 0)
2772                         ;       /* do nothing */
2773                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2774                         dev_err (hub_dev, "get_hub_status failed\n");
2775                 else {
2776                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2777                                 dev_dbg (hub_dev, "power change\n");
2778                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2779                         }
2780                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
2781                                 dev_dbg (hub_dev, "overcurrent change\n");
2782                                 msleep(500);    /* Cool down */
2783                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2784                                 hub_power_on(hub);
2785                         }
2786                 }
2787
2788                 hub->activating = 0;
2789
2790 loop:
2791                 usb_unlock_device(hdev);
2792                 usb_put_intf(intf);
2793
2794         } /* end while (1) */
2795 }
2796
2797 static int hub_thread(void *__unused)
2798 {
2799         /*
2800          * This thread doesn't need any user-level access,
2801          * so get rid of all our resources
2802          */
2803
2804         daemonize("khubd");
2805         allow_signal(SIGKILL);
2806
2807         /* Send me a signal to get me die (for debugging) */
2808         do {
2809                 hub_events();
2810                 wait_event_interruptible(khubd_wait, !list_empty(&hub_event_list));
2811                 try_to_freeze(PF_FREEZE);
2812         } while (!signal_pending(current));
2813
2814         pr_debug ("%s: khubd exiting\n", usbcore_name);
2815         complete_and_exit(&khubd_exited, 0);
2816 }
2817
2818 static struct usb_device_id hub_id_table [] = {
2819     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2820       .bDeviceClass = USB_CLASS_HUB},
2821     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2822       .bInterfaceClass = USB_CLASS_HUB},
2823     { }                                         /* Terminating entry */
2824 };
2825
2826 MODULE_DEVICE_TABLE (usb, hub_id_table);
2827
2828 static struct usb_driver hub_driver = {
2829         .owner =        THIS_MODULE,
2830         .name =         "hub",
2831         .probe =        hub_probe,
2832         .disconnect =   hub_disconnect,
2833         .suspend =      hub_suspend,
2834         .resume =       hub_resume,
2835         .ioctl =        hub_ioctl,
2836         .id_table =     hub_id_table,
2837 };
2838
2839 int usb_hub_init(void)
2840 {
2841         pid_t pid;
2842
2843         if (usb_register(&hub_driver) < 0) {
2844                 printk(KERN_ERR "%s: can't register hub driver\n",
2845                         usbcore_name);
2846                 return -1;
2847         }
2848
2849         pid = kernel_thread(hub_thread, NULL, CLONE_KERNEL);
2850         if (pid >= 0) {
2851                 khubd_pid = pid;
2852
2853                 return 0;
2854         }
2855
2856         /* Fall through if kernel_thread failed */
2857         usb_deregister(&hub_driver);
2858         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2859
2860         return -1;
2861 }
2862
2863 void usb_hub_cleanup(void)
2864 {
2865         int ret;
2866
2867         /* Kill the thread */
2868         ret = kill_proc(khubd_pid, SIGKILL, 1);
2869
2870         wait_for_completion(&khubd_exited);
2871
2872         /*
2873          * Hub resources are freed for us by usb_deregister. It calls
2874          * usb_driver_purge on every device which in turn calls that
2875          * devices disconnect function if it is using this driver.
2876          * The hub_disconnect function takes care of releasing the
2877          * individual hub resources. -greg
2878          */
2879         usb_deregister(&hub_driver);
2880 } /* usb_hub_cleanup() */
2881
2882
2883 static int config_descriptors_changed(struct usb_device *udev)
2884 {
2885         unsigned                        index;
2886         unsigned                        len = 0;
2887         struct usb_config_descriptor    *buf;
2888
2889         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2890                 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2891                         len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2892         }
2893         buf = kmalloc (len, SLAB_KERNEL);
2894         if (buf == NULL) {
2895                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2896                 /* assume the worst */
2897                 return 1;
2898         }
2899         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2900                 int length;
2901                 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2902
2903                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2904                                 old_length);
2905                 if (length < old_length) {
2906                         dev_dbg(&udev->dev, "config index %d, error %d\n",
2907                                         index, length);
2908                         break;
2909                 }
2910                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2911                                 != 0) {
2912                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2913                                 index, buf->bConfigurationValue);
2914                         break;
2915                 }
2916         }
2917         kfree(buf);
2918         return index != udev->descriptor.bNumConfigurations;
2919 }
2920
2921 /**
2922  * usb_reset_device - perform a USB port reset to reinitialize a device
2923  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2924  *
2925  * WARNING - don't reset any device unless drivers for all of its
2926  * interfaces are expecting that reset!  Maybe some driver->reset()
2927  * method should eventually help ensure sufficient cooperation.
2928  *
2929  * Do a port reset, reassign the device's address, and establish its
2930  * former operating configuration.  If the reset fails, or the device's
2931  * descriptors change from their values before the reset, or the original
2932  * configuration and altsettings cannot be restored, a flag will be set
2933  * telling khubd to pretend the device has been disconnected and then
2934  * re-connected.  All drivers will be unbound, and the device will be
2935  * re-enumerated and probed all over again.
2936  *
2937  * Returns 0 if the reset succeeded, -ENODEV if the device has been
2938  * flagged for logical disconnection, or some other negative error code
2939  * if the reset wasn't even attempted.
2940  *
2941  * The caller must own the device lock.  For example, it's safe to use
2942  * this from a driver probe() routine after downloading new firmware.
2943  * For calls that might not occur during probe(), drivers should lock
2944  * the device using usb_lock_device_for_reset().
2945  */
2946 int usb_reset_device(struct usb_device *udev)
2947 {
2948         struct usb_device               *parent_hdev = udev->parent;
2949         struct usb_hub                  *parent_hub;
2950         struct usb_device_descriptor    descriptor = udev->descriptor;
2951         struct usb_hub                  *hub = NULL;
2952         int                             i, ret = 0, port1 = -1;
2953
2954         if (udev->state == USB_STATE_NOTATTACHED ||
2955                         udev->state == USB_STATE_SUSPENDED) {
2956                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2957                                 udev->state);
2958                 return -EINVAL;
2959         }
2960
2961         if (!parent_hdev) {
2962                 /* this requires hcd-specific logic; see OHCI hc_restart() */
2963                 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2964                 return -EISDIR;
2965         }
2966
2967         for (i = 0; i < parent_hdev->maxchild; i++)
2968                 if (parent_hdev->children[i] == udev) {
2969                         port1 = i + 1;
2970                         break;
2971                 }
2972
2973         if (port1 < 0) {
2974                 /* If this ever happens, it's very bad */
2975                 dev_err(&udev->dev, "Can't locate device's port!\n");
2976                 return -ENOENT;
2977         }
2978         parent_hub = hdev_to_hub(parent_hdev);
2979
2980         /* If we're resetting an active hub, take some special actions */
2981         if (udev->actconfig &&
2982                         udev->actconfig->interface[0]->dev.driver ==
2983                                 &hub_driver.driver &&
2984                         (hub = hdev_to_hub(udev)) != NULL) {
2985                 hub_pre_reset(hub);
2986         }
2987
2988         set_bit(port1, parent_hub->busy_bits);
2989         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
2990
2991                 /* ep0 maxpacket size may change; let the HCD know about it.
2992                  * Other endpoints will be handled by re-enumeration. */
2993                 ep0_reinit(udev);
2994                 ret = hub_port_init(parent_hub, udev, port1, i);
2995                 if (ret >= 0)
2996                         break;
2997         }
2998         clear_bit(port1, parent_hub->busy_bits);
2999         if (ret < 0)
3000                 goto re_enumerate;
3001
3002         /* Device might have changed firmware (DFU or similar) */
3003         if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
3004                         || config_descriptors_changed (udev)) {
3005                 dev_info(&udev->dev, "device firmware changed\n");
3006                 udev->descriptor = descriptor;  /* for disconnect() calls */
3007                 goto re_enumerate;
3008         }
3009
3010         if (!udev->actconfig)
3011                 goto done;
3012
3013         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3014                         USB_REQ_SET_CONFIGURATION, 0,
3015                         udev->actconfig->desc.bConfigurationValue, 0,
3016                         NULL, 0, USB_CTRL_SET_TIMEOUT);
3017         if (ret < 0) {
3018                 dev_err(&udev->dev,
3019                         "can't restore configuration #%d (error=%d)\n",
3020                         udev->actconfig->desc.bConfigurationValue, ret);
3021                 goto re_enumerate;
3022         }
3023         usb_set_device_state(udev, USB_STATE_CONFIGURED);
3024
3025         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3026                 struct usb_interface *intf = udev->actconfig->interface[i];
3027                 struct usb_interface_descriptor *desc;
3028
3029                 /* set_interface resets host side toggle even
3030                  * for altsetting zero.  the interface may have no driver.
3031                  */
3032                 desc = &intf->cur_altsetting->desc;
3033                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3034                         desc->bAlternateSetting);
3035                 if (ret < 0) {
3036                         dev_err(&udev->dev, "failed to restore interface %d "
3037                                 "altsetting %d (error=%d)\n",
3038                                 desc->bInterfaceNumber,
3039                                 desc->bAlternateSetting,
3040                                 ret);
3041                         goto re_enumerate;
3042                 }
3043         }
3044
3045 done:
3046         if (hub)
3047                 hub_post_reset(hub);
3048         return 0;
3049
3050 re_enumerate:
3051         hub_port_logical_disconnect(parent_hub, port1);
3052         return -ENODEV;
3053 }