drivers/usb/core/hub.c

   1 /*
   2  * USB hub driver.
   3  *
   4  * (C) Copyright 1999 Linus Torvalds
   5  * (C) Copyright 1999 Johannes Erdfelt
   6  * (C) Copyright 1999 Gregory P. Smith
   7  * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
   8  *
   9  */
  10
  11 #include <linux/kernel.h>
  12 #include <linux/errno.h>
  13 #include <linux/module.h>
  14 #include <linux/moduleparam.h>
  15 #include <linux/completion.h>
  16 #include <linux/sched.h>
  17 #include <linux/list.h>
  18 #include <linux/slab.h>
  19 #include <linux/ioctl.h>
  20 #include <linux/usb.h>
  21 #include <linux/usbdevice_fs.h>
  22 #include <linux/kthread.h>
  23 #include <linux/mutex.h>
  24 #include <linux/freezer.h>
  25
  26 #include <asm/semaphore.h>
  27 #include <asm/uaccess.h>
  28 #include <asm/byteorder.h>
  29
  30 #include "usb.h"
  31 #include "hcd.h"
  32 #include "hub.h"
  33
  34 #ifdef  CONFIG_USB_PERSIST
  35 #define USB_PERSIST     1
  36 #else
  37 #define USB_PERSIST     0
  38 #endif
  39
  40 struct usb_hub {
  41         struct device           *intfdev;       /* the "interface" device */
  42         struct usb_device       *hdev;
  43         struct kref             kref;
  44         struct urb              *urb;           /* for interrupt polling pipe */
  45
  46         /* buffer for urb ... with extra space in case of babble */
  47         char                    (*buffer)[8];
  48         dma_addr_t              buffer_dma;     /* DMA address for buffer */
  49         union {
  50                 struct usb_hub_status   hub;
  51                 struct usb_port_status  port;
  52         }                       *status;        /* buffer for status reports */
  53         struct mutex            status_mutex;   /* for the status buffer */
  54
  55         int                     error;          /* last reported error */
  56         int                     nerrors;        /* track consecutive errors */
  57
  58         struct list_head        event_list;     /* hubs w/data or errs ready */
  59         unsigned long           event_bits[1];  /* status change bitmask */
  60         unsigned long           change_bits[1]; /* ports with logical connect
  61                                                         status change */
  62         unsigned long           busy_bits[1];   /* ports being reset or
  63                                                         resumed */
  64 #if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
  65 #error event_bits[] is too short!
  66 #endif
  67
  68         struct usb_hub_descriptor *descriptor;  /* class descriptor */
  69         struct usb_tt           tt;             /* Transaction Translator */
  70
  71         unsigned                mA_per_port;    /* current for each child */
  72
  73         unsigned                limited_power:1;
  74         unsigned                quiescing:1;
  75         unsigned                activating:1;
  76         unsigned                disconnected:1;
  77
  78         unsigned                has_indicators:1;
  79         u8                      indicator[USB_MAXCHILDREN];
  80         struct delayed_work     leds;
  81 };
  82
  83
  84 /* Protect struct usb_device->state and ->children members
  85  * Note: Both are also protected by ->dev.sem, except that ->state can
  86  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
  87 static DEFINE_SPINLOCK(device_state_lock);
  88
  89 /* khubd's worklist and its lock */
  90 static DEFINE_SPINLOCK(hub_event_lock);
  91 static LIST_HEAD(hub_event_list);       /* List of hubs needing servicing */
  92
  93 /* Wakes up khubd */
  94 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
  95
  96 static struct task_struct *khubd_task;
  97
  98 /* cycle leds on hubs that aren't blinking for attention */
  99 static int blinkenlights = 0;
 100 module_param (blinkenlights, bool, S_IRUGO);
 101 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
 102
 103 /*
 104  * As of 2.6.10 we introduce a new USB device initialization scheme which
 105  * closely resembles the way Windows works.  Hopefully it will be compatible
 106  * with a wider range of devices than the old scheme.  However some previously
 107  * working devices may start giving rise to "device not accepting address"
 108  * errors; if that happens the user can try the old scheme by adjusting the
 109  * following module parameters.
 110  *
 111  * For maximum flexibility there are two boolean parameters to control the
 112  * hub driver's behavior.  On the first initialization attempt, if the
 113  * "old_scheme_first" parameter is set then the old scheme will be used,
 114  * otherwise the new scheme is used.  If that fails and "use_both_schemes"
 115  * is set, then the driver will make another attempt, using the other scheme.
 116  */
 117 static int old_scheme_first = 0;
 118 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
 119 MODULE_PARM_DESC(old_scheme_first,
 120                  "start with the old device initialization scheme");
 121
 122 static int use_both_schemes = 1;
 123 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
 124 MODULE_PARM_DESC(use_both_schemes,
 125                 "try the other device initialization scheme if the "
 126                 "first one fails");
 127
 128
 129 static inline char *portspeed(int portstatus)
 130 {
 131         if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
 132                 return "480 Mb/s";
 133         else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
 134                 return "1.5 Mb/s";
 135         else
 136                 return "12 Mb/s";
 137 }
 138
 139 /* Note that hdev or one of its children must be locked! */
 140 static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
 141 {
 142         return usb_get_intfdata(hdev->actconfig->interface[0]);
 143 }
 144
 145 /* USB 2.0 spec Section 11.24.4.5 */
 146 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
 147 {
 148         int i, ret;
 149
 150         for (i = 0; i < 3; i++) {
 151                 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 152                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
 153                         USB_DT_HUB << 8, 0, data, size,
 154                         USB_CTRL_GET_TIMEOUT);
 155                 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
 156                         return ret;
 157         }
 158         return -EINVAL;
 159 }
 160
 161 /*
 162  * USB 2.0 spec Section 11.24.2.1
 163  */
 164 static int clear_hub_feature(struct usb_device *hdev, int feature)
 165 {
 166         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 167                 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
 168 }
 169
 170 /*
 171  * USB 2.0 spec Section 11.24.2.2
 172  */
 173 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
 174 {
 175         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 176                 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
 177                 NULL, 0, 1000);
 178 }
 179
 180 /*
 181  * USB 2.0 spec Section 11.24.2.13
 182  */
 183 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
 184 {
 185         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 186                 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
 187                 NULL, 0, 1000);
 188 }
 189
 190 /*
 191  * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
 192  * for info about using port indicators
 193  */
 194 static void set_port_led(
 195         struct usb_hub *hub,
 196         int port1,
 197         int selector
 198 )
 199 {
 200         int status = set_port_feature(hub->hdev, (selector << 8) | port1,
 201                         USB_PORT_FEAT_INDICATOR);
 202         if (status < 0)
 203                 dev_dbg (hub->intfdev,
 204                         "port %d indicator %s status %d\n",
 205                         port1,
 206                         ({ char *s; switch (selector) {
 207                         case HUB_LED_AMBER: s = "amber"; break;
 208                         case HUB_LED_GREEN: s = "green"; break;
 209                         case HUB_LED_OFF: s = "off"; break;
 210                         case HUB_LED_AUTO: s = "auto"; break;
 211                         default: s = "??"; break;
 212                         }; s; }),
 213                         status);
 214 }
 215
 216 #define LED_CYCLE_PERIOD        ((2*HZ)/3)
 217
 218 static void led_work (struct work_struct *work)
 219 {
 220         struct usb_hub          *hub =
 221                 container_of(work, struct usb_hub, leds.work);
 222         struct usb_device       *hdev = hub->hdev;
 223         unsigned                i;
 224         unsigned                changed = 0;
 225         int                     cursor = -1;
 226
 227         if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
 228                 return;
 229
 230         for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
 231                 unsigned        selector, mode;
 232
 233                 /* 30%-50% duty cycle */
 234
 235                 switch (hub->indicator[i]) {
 236                 /* cycle marker */
 237                 case INDICATOR_CYCLE:
 238                         cursor = i;
 239                         selector = HUB_LED_AUTO;
 240                         mode = INDICATOR_AUTO;
 241                         break;
 242                 /* blinking green = sw attention */
 243                 case INDICATOR_GREEN_BLINK:
 244                         selector = HUB_LED_GREEN;
 245                         mode = INDICATOR_GREEN_BLINK_OFF;
 246                         break;
 247                 case INDICATOR_GREEN_BLINK_OFF:
 248                         selector = HUB_LED_OFF;
 249                         mode = INDICATOR_GREEN_BLINK;
 250                         break;
 251                 /* blinking amber = hw attention */
 252                 case INDICATOR_AMBER_BLINK:
 253                         selector = HUB_LED_AMBER;
 254                         mode = INDICATOR_AMBER_BLINK_OFF;
 255                         break;
 256                 case INDICATOR_AMBER_BLINK_OFF:
 257                         selector = HUB_LED_OFF;
 258                         mode = INDICATOR_AMBER_BLINK;
 259                         break;
 260                 /* blink green/amber = reserved */
 261                 case INDICATOR_ALT_BLINK:
 262                         selector = HUB_LED_GREEN;
 263                         mode = INDICATOR_ALT_BLINK_OFF;
 264                         break;
 265                 case INDICATOR_ALT_BLINK_OFF:
 266                         selector = HUB_LED_AMBER;
 267                         mode = INDICATOR_ALT_BLINK;
 268                         break;
 269                 default:
 270                         continue;
 271                 }
 272                 if (selector != HUB_LED_AUTO)
 273                         changed = 1;
 274                 set_port_led(hub, i + 1, selector);
 275                 hub->indicator[i] = mode;
 276         }
 277         if (!changed && blinkenlights) {
 278                 cursor++;
 279                 cursor %= hub->descriptor->bNbrPorts;
 280                 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
 281                 hub->indicator[cursor] = INDICATOR_CYCLE;
 282                 changed++;
 283         }
 284         if (changed)
 285                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 286 }
 287
 288 /* use a short timeout for hub/port status fetches */
 289 #define USB_STS_TIMEOUT         1000
 290 #define USB_STS_RETRIES         5
 291
 292 /*
 293  * USB 2.0 spec Section 11.24.2.6
 294  */
 295 static int get_hub_status(struct usb_device *hdev,
 296                 struct usb_hub_status *data)
 297 {
 298         int i, status = -ETIMEDOUT;
 299
 300         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
 301                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 302                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
 303                         data, sizeof(*data), USB_STS_TIMEOUT);
 304         }
 305         return status;
 306 }
 307
 308 /*
 309  * USB 2.0 spec Section 11.24.2.7
 310  */
 311 static int get_port_status(struct usb_device *hdev, int port1,
 312                 struct usb_port_status *data)
 313 {
 314         int i, status = -ETIMEDOUT;
 315
 316         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
 317                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 318                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
 319                         data, sizeof(*data), USB_STS_TIMEOUT);
 320         }
 321         return status;
 322 }
 323
 324 static void kick_khubd(struct usb_hub *hub)
 325 {
 326         unsigned long   flags;
 327
 328         /* Suppress autosuspend until khubd runs */
 329         to_usb_interface(hub->intfdev)->pm_usage_cnt = 1;
 330
 331         spin_lock_irqsave(&hub_event_lock, flags);
 332         if (!hub->disconnected & list_empty(&hub->event_list)) {
 333                 list_add_tail(&hub->event_list, &hub_event_list);
 334                 wake_up(&khubd_wait);
 335         }
 336         spin_unlock_irqrestore(&hub_event_lock, flags);
 337 }
 338
 339 void usb_kick_khubd(struct usb_device *hdev)
 340 {
 341         /* FIXME: What if hdev isn't bound to the hub driver? */
 342         kick_khubd(hdev_to_hub(hdev));
 343 }
 344
 345
 346 /* completion function, fires on port status changes and various faults */
 347 static void hub_irq(struct urb *urb)
 348 {
 349         struct usb_hub *hub = urb->context;
 350         int status;
 351         int i;
 352         unsigned long bits;
 353
 354         switch (urb->status) {
 355         case -ENOENT:           /* synchronous unlink */
 356         case -ECONNRESET:       /* async unlink */
 357         case -ESHUTDOWN:        /* hardware going away */
 358                 return;
 359
 360         default:                /* presumably an error */
 361                 /* Cause a hub reset after 10 consecutive errors */
 362                 dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
 363                 if ((++hub->nerrors < 10) || hub->error)
 364                         goto resubmit;
 365                 hub->error = urb->status;
 366                 /* FALL THROUGH */
 367
 368         /* let khubd handle things */
 369         case 0:                 /* we got data:  port status changed */
 370                 bits = 0;
 371                 for (i = 0; i < urb->actual_length; ++i)
 372                         bits |= ((unsigned long) ((*hub->buffer)[i]))
 373                                         << (i*8);
 374                 hub->event_bits[0] = bits;
 375                 break;
 376         }
 377
 378         hub->nerrors = 0;
 379
 380         /* Something happened, let khubd figure it out */
 381         kick_khubd(hub);
 382
 383 resubmit:
 384         if (hub->quiescing)
 385                 return;
 386
 387         if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
 388                         && status != -ENODEV && status != -EPERM)
 389                 dev_err (hub->intfdev, "resubmit --> %d\n", status);
 390 }
 391
 392 /* USB 2.0 spec Section 11.24.2.3 */
 393 static inline int
 394 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
 395 {
 396         return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 397                                HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
 398                                tt, NULL, 0, 1000);
 399 }
 400
 401 /*
 402  * enumeration blocks khubd for a long time. we use keventd instead, since
 403  * long blocking there is the exception, not the rule.  accordingly, HCDs
 404  * talking to TTs must queue control transfers (not just bulk and iso), so
 405  * both can talk to the same hub concurrently.
 406  */
 407 static void hub_tt_kevent (struct work_struct *work)
 408 {
 409         struct usb_hub          *hub =
 410                 container_of(work, struct usb_hub, tt.kevent);
 411         unsigned long           flags;
 412         int                     limit = 100;
 413
 414         spin_lock_irqsave (&hub->tt.lock, flags);
 415         while (--limit && !list_empty (&hub->tt.clear_list)) {
 416                 struct list_head        *temp;
 417                 struct usb_tt_clear     *clear;
 418                 struct usb_device       *hdev = hub->hdev;
 419                 int                     status;
 420
 421                 temp = hub->tt.clear_list.next;
 422                 clear = list_entry (temp, struct usb_tt_clear, clear_list);
 423                 list_del (&clear->clear_list);
 424
 425                 /* drop lock so HCD can concurrently report other TT errors */
 426                 spin_unlock_irqrestore (&hub->tt.lock, flags);
 427                 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
 428                 spin_lock_irqsave (&hub->tt.lock, flags);
 429
 430                 if (status)
 431                         dev_err (&hdev->dev,
 432                                 "clear tt %d (%04x) error %d\n",
 433                                 clear->tt, clear->devinfo, status);
 434                 kfree(clear);
 435         }
 436         spin_unlock_irqrestore (&hub->tt.lock, flags);
 437 }
 438
 439 /**
 440  * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
 441  * @udev: the device whose split transaction failed
 442  * @pipe: identifies the endpoint of the failed transaction
 443  *
 444  * High speed HCDs use this to tell the hub driver that some split control or
 445  * bulk transaction failed in a way that requires clearing internal state of
 446  * a transaction translator.  This is normally detected (and reported) from
 447  * interrupt context.
 448  *
 449  * It may not be possible for that hub to handle additional full (or low)
 450  * speed transactions until that state is fully cleared out.
 451  */
 452 void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
 453 {
 454         struct usb_tt           *tt = udev->tt;
 455         unsigned long           flags;
 456         struct usb_tt_clear     *clear;
 457
 458         /* we've got to cope with an arbitrary number of pending TT clears,
 459          * since each TT has "at least two" buffers that can need it (and
 460          * there can be many TTs per hub).  even if they're uncommon.
 461          */
 462         if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) {
 463                 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
 464                 /* FIXME recover somehow ... RESET_TT? */
 465                 return;
 466         }
 467
 468         /* info that CLEAR_TT_BUFFER needs */
 469         clear->tt = tt->multi ? udev->ttport : 1;
 470         clear->devinfo = usb_pipeendpoint (pipe);
 471         clear->devinfo |= udev->devnum << 4;
 472         clear->devinfo |= usb_pipecontrol (pipe)
 473                         ? (USB_ENDPOINT_XFER_CONTROL << 11)
 474                         : (USB_ENDPOINT_XFER_BULK << 11);
 475         if (usb_pipein (pipe))
 476                 clear->devinfo |= 1 << 15;
 477
 478         /* tell keventd to clear state for this TT */
 479         spin_lock_irqsave (&tt->lock, flags);
 480         list_add_tail (&clear->clear_list, &tt->clear_list);
 481         schedule_work (&tt->kevent);
 482         spin_unlock_irqrestore (&tt->lock, flags);
 483 }
 484
 485 static void hub_power_on(struct usb_hub *hub)
 486 {
 487         int port1;
 488         unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
 489         u16 wHubCharacteristics =
 490                         le16_to_cpu(hub->descriptor->wHubCharacteristics);
 491
 492         /* Enable power on each port.  Some hubs have reserved values
 493          * of LPSM (> 2) in their descriptors, even though they are
 494          * USB 2.0 hubs.  Some hubs do not implement port-power switching
 495          * but only emulate it.  In all cases, the ports won't work
 496          * unless we send these messages to the hub.
 497          */
 498         if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
 499                 dev_dbg(hub->intfdev, "enabling power on all ports\n");
 500         else
 501                 dev_dbg(hub->intfdev, "trying to enable port power on "
 502                                 "non-switchable hub\n");
 503         for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
 504                 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
 505
 506         /* Wait at least 100 msec for power to become stable */
 507         msleep(max(pgood_delay, (unsigned) 100));
 508 }
 509
 510 static void hub_quiesce(struct usb_hub *hub)
 511 {
 512         /* (nonblocking) khubd and related activity won't re-trigger */
 513         hub->quiescing = 1;
 514         hub->activating = 0;
 515
 516         /* (blocking) stop khubd and related activity */
 517         usb_kill_urb(hub->urb);
 518         if (hub->has_indicators)
 519                 cancel_delayed_work(&hub->leds);
 520         if (hub->has_indicators || hub->tt.hub)
 521                 flush_scheduled_work();
 522 }
 523
 524 static void hub_activate(struct usb_hub *hub)
 525 {
 526         int     status;
 527
 528         hub->quiescing = 0;
 529         hub->activating = 1;
 530
 531         status = usb_submit_urb(hub->urb, GFP_NOIO);
 532         if (status < 0)
 533                 dev_err(hub->intfdev, "activate --> %d\n", status);
 534         if (hub->has_indicators && blinkenlights)
 535                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 536
 537         /* scan all ports ASAP */
 538         kick_khubd(hub);
 539 }
 540
 541 static int hub_hub_status(struct usb_hub *hub,
 542                 u16 *status, u16 *change)
 543 {
 544         int ret;
 545
 546         mutex_lock(&hub->status_mutex);
 547         ret = get_hub_status(hub->hdev, &hub->status->hub);
 548         if (ret < 0)
 549                 dev_err (hub->intfdev,
 550                         "%s failed (err = %d)\n", __FUNCTION__, ret);
 551         else {
 552                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
 553                 *change = le16_to_cpu(hub->status->hub.wHubChange);
 554                 ret = 0;
 555         }
 556         mutex_unlock(&hub->status_mutex);
 557         return ret;
 558 }
 559
 560 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
 561 {
 562         struct usb_device *hdev = hub->hdev;
 563         int ret = 0;
 564
 565         if (hdev->children[port1-1] && set_state)
 566                 usb_set_device_state(hdev->children[port1-1],
 567                                 USB_STATE_NOTATTACHED);
 568         if (!hub->error)
 569                 ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
 570         if (ret)
 571                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
 572                                 port1, ret);
 573         return ret;
 574 }
 575
 576 /*
 577  * Disable a port and mark a logical connnect-change event, so that some
 578  * time later khubd will disconnect() any existing usb_device on the port
 579  * and will re-enumerate if there actually is a device attached.
 580  */
 581 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
 582 {
 583         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
 584         hub_port_disable(hub, port1, 1);
 585
 586         /* FIXME let caller ask to power down the port:
 587          *  - some devices won't enumerate without a VBUS power cycle
 588          *  - SRP saves power that way
 589          *  - ... new call, TBD ...
 590          * That's easy if this hub can switch power per-port, and
 591          * khubd reactivates the port later (timer, SRP, etc).
 592          * Powerdown must be optional, because of reset/DFU.
 593          */
 594
 595         set_bit(port1, hub->change_bits);
 596         kick_khubd(hub);
 597 }
 598
 599 /* caller has locked the hub device */
 600 static int hub_pre_reset(struct usb_interface *intf)
 601 {
 602         struct usb_hub *hub = usb_get_intfdata(intf);
 603         struct usb_device *hdev = hub->hdev;
 604         int i;
 605
 606         /* Disconnect all the children */
 607         for (i = 0; i < hdev->maxchild; ++i) {
 608                 if (hdev->children[i])
 609                         usb_disconnect(&hdev->children[i]);
 610         }
 611         hub_quiesce(hub);
 612         return 0;
 613 }
 614
 615 /* caller has locked the hub device */
 616 static int hub_post_reset(struct usb_interface *intf)
 617 {
 618         struct usb_hub *hub = usb_get_intfdata(intf);
 619
 620         hub_power_on(hub);
 621         hub_activate(hub);
 622         return 0;
 623 }
 624
 625 static int hub_configure(struct usb_hub *hub,
 626         struct usb_endpoint_descriptor *endpoint)
 627 {
 628         struct usb_device *hdev = hub->hdev;
 629         struct device *hub_dev = hub->intfdev;
 630         u16 hubstatus, hubchange;
 631         u16 wHubCharacteristics;
 632         unsigned int pipe;
 633         int maxp, ret;
 634         char *message;
 635
 636         hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
 637                         &hub->buffer_dma);
 638         if (!hub->buffer) {
 639                 message = "can't allocate hub irq buffer";
 640                 ret = -ENOMEM;
 641                 goto fail;
 642         }
 643
 644         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
 645         if (!hub->status) {
 646                 message = "can't kmalloc hub status buffer";
 647                 ret = -ENOMEM;
 648                 goto fail;
 649         }
 650         mutex_init(&hub->status_mutex);
 651
 652         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
 653         if (!hub->descriptor) {
 654                 message = "can't kmalloc hub descriptor";
 655                 ret = -ENOMEM;
 656                 goto fail;
 657         }
 658
 659         /* Request the entire hub descriptor.
 660          * hub->descriptor can handle USB_MAXCHILDREN ports,
 661          * but the hub can/will return fewer bytes here.
 662          */
 663         ret = get_hub_descriptor(hdev, hub->descriptor,
 664                         sizeof(*hub->descriptor));
 665         if (ret < 0) {
 666                 message = "can't read hub descriptor";
 667                 goto fail;
 668         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
 669                 message = "hub has too many ports!";
 670                 ret = -ENODEV;
 671                 goto fail;
 672         }
 673
 674         hdev->maxchild = hub->descriptor->bNbrPorts;
 675         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
 676                 (hdev->maxchild == 1) ? "" : "s");
 677
 678         wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
 679
 680         if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
 681                 int     i;
 682                 char    portstr [USB_MAXCHILDREN + 1];
 683
 684                 for (i = 0; i < hdev->maxchild; i++)
 685                         portstr[i] = hub->descriptor->DeviceRemovable
 686                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
 687                                 ? 'F' : 'R';
 688                 portstr[hdev->maxchild] = 0;
 689                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
 690         } else
 691                 dev_dbg(hub_dev, "standalone hub\n");
 692
 693         switch (wHubCharacteristics & HUB_CHAR_LPSM) {
 694                 case 0x00:
 695                         dev_dbg(hub_dev, "ganged power switching\n");
 696                         break;
 697                 case 0x01:
 698                         dev_dbg(hub_dev, "individual port power switching\n");
 699                         break;
 700                 case 0x02:
 701                 case 0x03:
 702                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
 703                         break;
 704         }
 705
 706         switch (wHubCharacteristics & HUB_CHAR_OCPM) {
 707                 case 0x00:
 708                         dev_dbg(hub_dev, "global over-current protection\n");
 709                         break;
 710                 case 0x08:
 711                         dev_dbg(hub_dev, "individual port over-current protection\n");
 712                         break;
 713                 case 0x10:
 714                 case 0x18:
 715                         dev_dbg(hub_dev, "no over-current protection\n");
 716                         break;
 717         }
 718
 719         spin_lock_init (&hub->tt.lock);
 720         INIT_LIST_HEAD (&hub->tt.clear_list);
 721         INIT_WORK (&hub->tt.kevent, hub_tt_kevent);
 722         switch (hdev->descriptor.bDeviceProtocol) {
 723                 case 0:
 724                         break;
 725                 case 1:
 726                         dev_dbg(hub_dev, "Single TT\n");
 727                         hub->tt.hub = hdev;
 728                         break;
 729                 case 2:
 730                         ret = usb_set_interface(hdev, 0, 1);
 731                         if (ret == 0) {
 732                                 dev_dbg(hub_dev, "TT per port\n");
 733                                 hub->tt.multi = 1;
 734                         } else
 735                                 dev_err(hub_dev, "Using single TT (err %d)\n",
 736                                         ret);
 737                         hub->tt.hub = hdev;
 738                         break;
 739                 default:
 740                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
 741                                 hdev->descriptor.bDeviceProtocol);
 742                         break;
 743         }
 744
 745         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
 746         switch (wHubCharacteristics & HUB_CHAR_TTTT) {
 747                 case HUB_TTTT_8_BITS:
 748                         if (hdev->descriptor.bDeviceProtocol != 0) {
 749                                 hub->tt.think_time = 666;
 750                                 dev_dbg(hub_dev, "TT requires at most %d "
 751                                                 "FS bit times (%d ns)\n",
 752                                         8, hub->tt.think_time);
 753                         }
 754                         break;
 755                 case HUB_TTTT_16_BITS:
 756                         hub->tt.think_time = 666 * 2;
 757                         dev_dbg(hub_dev, "TT requires at most %d "
 758                                         "FS bit times (%d ns)\n",
 759                                 16, hub->tt.think_time);
 760                         break;
 761                 case HUB_TTTT_24_BITS:
 762                         hub->tt.think_time = 666 * 3;
 763                         dev_dbg(hub_dev, "TT requires at most %d "
 764                                         "FS bit times (%d ns)\n",
 765                                 24, hub->tt.think_time);
 766                         break;
 767                 case HUB_TTTT_32_BITS:
 768                         hub->tt.think_time = 666 * 4;
 769                         dev_dbg(hub_dev, "TT requires at most %d "
 770                                         "FS bit times (%d ns)\n",
 771                                 32, hub->tt.think_time);
 772                         break;
 773         }
 774
 775         /* probe() zeroes hub->indicator[] */
 776         if (wHubCharacteristics & HUB_CHAR_PORTIND) {
 777                 hub->has_indicators = 1;
 778                 dev_dbg(hub_dev, "Port indicators are supported\n");
 779         }
 780
 781         dev_dbg(hub_dev, "power on to power good time: %dms\n",
 782                 hub->descriptor->bPwrOn2PwrGood * 2);
 783
 784         /* power budgeting mostly matters with bus-powered hubs,
 785          * and battery-powered root hubs (may provide just 8 mA).
 786          */
 787         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
 788         if (ret < 2) {
 789                 message = "can't get hub status";
 790                 goto fail;
 791         }
 792         le16_to_cpus(&hubstatus);
 793         if (hdev == hdev->bus->root_hub) {
 794                 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
 795                         hub->mA_per_port = 500;
 796                 else {
 797                         hub->mA_per_port = hdev->bus_mA;
 798                         hub->limited_power = 1;
 799                 }
 800         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
 801                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
 802                         hub->descriptor->bHubContrCurrent);
 803                 hub->limited_power = 1;
 804                 if (hdev->maxchild > 0) {
 805                         int remaining = hdev->bus_mA -
 806                                         hub->descriptor->bHubContrCurrent;
 807
 808                         if (remaining < hdev->maxchild * 100)
 809                                 dev_warn(hub_dev,
 810                                         "insufficient power available "
 811                                         "to use all downstream ports\n");
 812                         hub->mA_per_port = 100;         /* 7.2.1.1 */
 813                 }
 814         } else {        /* Self-powered external hub */
 815                 /* FIXME: What about battery-powered external hubs that
 816                  * provide less current per port? */
 817                 hub->mA_per_port = 500;
 818         }
 819         if (hub->mA_per_port < 500)
 820                 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
 821                                 hub->mA_per_port);
 822
 823         ret = hub_hub_status(hub, &hubstatus, &hubchange);
 824         if (ret < 0) {
 825                 message = "can't get hub status";
 826                 goto fail;
 827         }
 828
 829         /* local power status reports aren't always correct */
 830         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
 831                 dev_dbg(hub_dev, "local power source is %s\n",
 832                         (hubstatus & HUB_STATUS_LOCAL_POWER)
 833                         ? "lost (inactive)" : "good");
 834
 835         if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
 836                 dev_dbg(hub_dev, "%sover-current condition exists\n",
 837                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
 838
 839         /* set up the interrupt endpoint
 840          * We use the EP's maxpacket size instead of (PORTS+1+7)/8
 841          * bytes as USB2.0[11.12.3] says because some hubs are known
 842          * to send more data (and thus cause overflow). For root hubs,
 843          * maxpktsize is defined in hcd.c's fake endpoint descriptors
 844          * to be big enough for at least USB_MAXCHILDREN ports. */
 845         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
 846         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
 847
 848         if (maxp > sizeof(*hub->buffer))
 849                 maxp = sizeof(*hub->buffer);
 850
 851         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
 852         if (!hub->urb) {
 853                 message = "couldn't allocate interrupt urb";
 854                 ret = -ENOMEM;
 855                 goto fail;
 856         }
 857
 858         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
 859                 hub, endpoint->bInterval);
 860         hub->urb->transfer_dma = hub->buffer_dma;
 861         hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 862
 863         /* maybe cycle the hub leds */
 864         if (hub->has_indicators && blinkenlights)
 865                 hub->indicator [0] = INDICATOR_CYCLE;
 866
 867         hub_power_on(hub);
 868         hub_activate(hub);
 869         return 0;
 870
 871 fail:
 872         dev_err (hub_dev, "config failed, %s (err %d)\n",
 873                         message, ret);
 874         /* hub_disconnect() frees urb and descriptor */
 875         return ret;
 876 }
 877
 878 static void hub_release(struct kref *kref)
 879 {
 880         struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
 881
 882         usb_put_intf(to_usb_interface(hub->intfdev));
 883         kfree(hub);
 884 }
 885
 886 static unsigned highspeed_hubs;
 887
 888 static void hub_disconnect(struct usb_interface *intf)
 889 {
 890         struct usb_hub *hub = usb_get_intfdata (intf);
 891
 892         /* Take the hub off the event list and don't let it be added again */
 893         spin_lock_irq(&hub_event_lock);
 894         list_del_init(&hub->event_list);
 895         hub->disconnected = 1;
 896         spin_unlock_irq(&hub_event_lock);
 897
 898         /* Disconnect all children and quiesce the hub */
 899         hub->error = 0;
 900         hub_pre_reset(intf);
 901
 902         usb_set_intfdata (intf, NULL);
 903
 904         if (hub->hdev->speed == USB_SPEED_HIGH)
 905                 highspeed_hubs--;
 906
 907         usb_free_urb(hub->urb);
 908         kfree(hub->descriptor);
 909         kfree(hub->status);
 910         usb_buffer_free(hub->hdev, sizeof(*hub->buffer), hub->buffer,
 911                         hub->buffer_dma);
 912
 913         kref_put(&hub->kref, hub_release);
 914 }
 915
 916 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
 917 {
 918         struct usb_host_interface *desc;
 919         struct usb_endpoint_descriptor *endpoint;
 920         struct usb_device *hdev;
 921         struct usb_hub *hub;
 922
 923         desc = intf->cur_altsetting;
 924         hdev = interface_to_usbdev(intf);
 925
 926 #ifdef  CONFIG_USB_OTG_BLACKLIST_HUB
 927         if (hdev->parent) {
 928                 dev_warn(&intf->dev, "ignoring external hub\n");
 929                 return -ENODEV;
 930         }
 931 #endif
 932
 933         /* Some hubs have a subclass of 1, which AFAICT according to the */
 934         /*  specs is not defined, but it works */
 935         if ((desc->desc.bInterfaceSubClass != 0) &&
 936             (desc->desc.bInterfaceSubClass != 1)) {
 937 descriptor_error:
 938                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
 939                 return -EIO;
 940         }
 941
 942         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
 943         if (desc->desc.bNumEndpoints != 1)
 944                 goto descriptor_error;
 945
 946         endpoint = &desc->endpoint[0].desc;
 947
 948         /* If it's not an interrupt in endpoint, we'd better punt! */
 949         if (!usb_endpoint_is_int_in(endpoint))
 950                 goto descriptor_error;
 951
 952         /* We found a hub */
 953         dev_info (&intf->dev, "USB hub found\n");
 954
 955         hub = kzalloc(sizeof(*hub), GFP_KERNEL);
 956         if (!hub) {
 957                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
 958                 return -ENOMEM;
 959         }
 960
 961         kref_init(&hub->kref);
 962         INIT_LIST_HEAD(&hub->event_list);
 963         hub->intfdev = &intf->dev;
 964         hub->hdev = hdev;
 965         INIT_DELAYED_WORK(&hub->leds, led_work);
 966         usb_get_intf(intf);
 967
 968         usb_set_intfdata (intf, hub);
 969         intf->needs_remote_wakeup = 1;
 970
 971         if (hdev->speed == USB_SPEED_HIGH)
 972                 highspeed_hubs++;
 973
 974         if (hub_configure(hub, endpoint) >= 0)
 975                 return 0;
 976
 977         hub_disconnect (intf);
 978         return -ENODEV;
 979 }
 980
 981 static int
 982 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
 983 {
 984         struct usb_device *hdev = interface_to_usbdev (intf);
 985
 986         /* assert ifno == 0 (part of hub spec) */
 987         switch (code) {
 988         case USBDEVFS_HUB_PORTINFO: {
 989                 struct usbdevfs_hub_portinfo *info = user_data;
 990                 int i;
 991
 992                 spin_lock_irq(&device_state_lock);
 993                 if (hdev->devnum <= 0)
 994                         info->nports = 0;
 995                 else {
 996                         info->nports = hdev->maxchild;
 997                         for (i = 0; i < info->nports; i++) {
 998                                 if (hdev->children[i] == NULL)
 999                                         info->port[i] = 0;
1000                                 else
1001                                         info->port[i] =
1002                                                 hdev->children[i]->devnum;
1003                         }
1004                 }
1005                 spin_unlock_irq(&device_state_lock);
1006
1007                 return info->nports + 1;
1008                 }
1009
1010         default:
1011                 return -ENOSYS;
1012         }
1013 }
1014
1015
1016 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1017 {
1018         int i;
1019
1020         for (i = 0; i < udev->maxchild; ++i) {
1021                 if (udev->children[i])
1022                         recursively_mark_NOTATTACHED(udev->children[i]);
1023         }
1024         if (udev->state == USB_STATE_SUSPENDED)
1025                 udev->discon_suspended = 1;
1026         udev->state = USB_STATE_NOTATTACHED;
1027 }
1028
1029 /**
1030  * usb_set_device_state - change a device's current state (usbcore, hcds)
1031  * @udev: pointer to device whose state should be changed
1032  * @new_state: new state value to be stored
1033  *
1034  * udev->state is _not_ fully protected by the device lock.  Although
1035  * most transitions are made only while holding the lock, the state can
1036  * can change to USB_STATE_NOTATTACHED at almost any time.  This
1037  * is so that devices can be marked as disconnected as soon as possible,
1038  * without having to wait for any semaphores to be released.  As a result,
1039  * all changes to any device's state must be protected by the
1040  * device_state_lock spinlock.
1041  *
1042  * Once a device has been added to the device tree, all changes to its state
1043  * should be made using this routine.  The state should _not_ be set directly.
1044  *
1045  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1046  * Otherwise udev->state is set to new_state, and if new_state is
1047  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1048  * to USB_STATE_NOTATTACHED.
1049  */
1050 void usb_set_device_state(struct usb_device *udev,
1051                 enum usb_device_state new_state)
1052 {
1053         unsigned long flags;
1054
1055         spin_lock_irqsave(&device_state_lock, flags);
1056         if (udev->state == USB_STATE_NOTATTACHED)
1057                 ;       /* do nothing */
1058         else if (new_state != USB_STATE_NOTATTACHED) {
1059
1060                 /* root hub wakeup capabilities are managed out-of-band
1061                  * and may involve silicon errata ... ignore them here.
1062                  */
1063                 if (udev->parent) {
1064                         if (udev->state == USB_STATE_SUSPENDED
1065                                         || new_state == USB_STATE_SUSPENDED)
1066                                 ;       /* No change to wakeup settings */
1067                         else if (new_state == USB_STATE_CONFIGURED)
1068                                 device_init_wakeup(&udev->dev,
1069                                         (udev->actconfig->desc.bmAttributes
1070                                          & USB_CONFIG_ATT_WAKEUP));
1071                         else
1072                                 device_init_wakeup(&udev->dev, 0);
1073                 }
1074                 udev->state = new_state;
1075         } else
1076                 recursively_mark_NOTATTACHED(udev);
1077         spin_unlock_irqrestore(&device_state_lock, flags);
1078 }
1079
1080 static void choose_address(struct usb_device *udev)
1081 {
1082         int             devnum;
1083         struct usb_bus  *bus = udev->bus;
1084
1085         /* If khubd ever becomes multithreaded, this will need a lock */
1086
1087         /* Try to allocate the next devnum beginning at bus->devnum_next. */
1088         devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1089                         bus->devnum_next);
1090         if (devnum >= 128)
1091                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1092
1093         bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1094
1095         if (devnum < 128) {
1096                 set_bit(devnum, bus->devmap.devicemap);
1097                 udev->devnum = devnum;
1098         }
1099 }
1100
1101 static void release_address(struct usb_device *udev)
1102 {
1103         if (udev->devnum > 0) {
1104                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1105                 udev->devnum = -1;
1106         }
1107 }
1108
1109 #ifdef  CONFIG_USB_SUSPEND
1110
1111 static void usb_stop_pm(struct usb_device *udev)
1112 {
1113         /* Synchronize with the ksuspend thread to prevent any more
1114          * autosuspend requests from being submitted, and decrement
1115          * the parent's count of unsuspended children.
1116          */
1117         usb_pm_lock(udev);
1118         if (udev->parent && !udev->discon_suspended)
1119                 usb_autosuspend_device(udev->parent);
1120         usb_pm_unlock(udev);
1121
1122         /* Stop any autosuspend requests already submitted */
1123         cancel_rearming_delayed_work(&udev->autosuspend);
1124 }
1125
1126 #else
1127
1128 static inline void usb_stop_pm(struct usb_device *udev)
1129 { }
1130
1131 #endif
1132
1133 /**
1134  * usb_disconnect - disconnect a device (usbcore-internal)
1135  * @pdev: pointer to device being disconnected
1136  * Context: !in_interrupt ()
1137  *
1138  * Something got disconnected. Get rid of it and all of its children.
1139  *
1140  * If *pdev is a normal device then the parent hub must already be locked.
1141  * If *pdev is a root hub then this routine will acquire the
1142  * usb_bus_list_lock on behalf of the caller.
1143  *
1144  * Only hub drivers (including virtual root hub drivers for host
1145  * controllers) should ever call this.
1146  *
1147  * This call is synchronous, and may not be used in an interrupt context.
1148  */
1149 void usb_disconnect(struct usb_device **pdev)
1150 {
1151         struct usb_device       *udev = *pdev;
1152         int                     i;
1153
1154         if (!udev) {
1155                 pr_debug ("%s nodev\n", __FUNCTION__);
1156                 return;
1157         }
1158
1159         /* mark the device as inactive, so any further urb submissions for
1160          * this device (and any of its children) will fail immediately.
1161          * this quiesces everyting except pending urbs.
1162          */
1163         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1164         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1165
1166         usb_lock_device(udev);
1167
1168         /* Free up all the children before we remove this device */
1169         for (i = 0; i < USB_MAXCHILDREN; i++) {
1170                 if (udev->children[i])
1171                         usb_disconnect(&udev->children[i]);
1172         }
1173
1174         /* deallocate hcd/hardware state ... nuking all pending urbs and
1175          * cleaning up all state associated with the current configuration
1176          * so that the hardware is now fully quiesced.
1177          */
1178         dev_dbg (&udev->dev, "unregistering device\n");
1179         usb_disable_device(udev, 0);
1180
1181         usb_unlock_device(udev);
1182
1183         /* Unregister the device.  The device driver is responsible
1184          * for removing the device files from usbfs and sysfs and for
1185          * de-configuring the device.
1186          */
1187         device_del(&udev->dev);
1188
1189         /* Free the device number and delete the parent's children[]
1190          * (or root_hub) pointer.
1191          */
1192         release_address(udev);
1193
1194         /* Avoid races with recursively_mark_NOTATTACHED() */
1195         spin_lock_irq(&device_state_lock);
1196         *pdev = NULL;
1197         spin_unlock_irq(&device_state_lock);
1198
1199         usb_stop_pm(udev);
1200
1201         put_device(&udev->dev);
1202 }
1203
1204 #ifdef DEBUG
1205 static void show_string(struct usb_device *udev, char *id, char *string)
1206 {
1207         if (!string)
1208                 return;
1209         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1210 }
1211
1212 #else
1213 static inline void show_string(struct usb_device *udev, char *id, char *string)
1214 {}
1215 #endif
1216
1217
1218 #ifdef  CONFIG_USB_OTG
1219 #include "otg_whitelist.h"
1220 #endif
1221
1222 /**
1223  * usb_new_device - perform initial device setup (usbcore-internal)
1224  * @udev: newly addressed device (in ADDRESS state)
1225  *
1226  * This is called with devices which have been enumerated, but not yet
1227  * configured.  The device descriptor is available, but not descriptors
1228  * for any device configuration.  The caller must have locked either
1229  * the parent hub (if udev is a normal device) or else the
1230  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1231  * udev has already been installed, but udev is not yet visible through
1232  * sysfs or other filesystem code.
1233  *
1234  * It will return if the device is configured properly or not.  Zero if
1235  * the interface was registered with the driver core; else a negative
1236  * errno value.
1237  *
1238  * This call is synchronous, and may not be used in an interrupt context.
1239  *
1240  * Only the hub driver or root-hub registrar should ever call this.
1241  */
1242 int usb_new_device(struct usb_device *udev)
1243 {
1244         int err;
1245
1246         /* Determine quirks */
1247         usb_detect_quirks(udev);
1248
1249         err = usb_get_configuration(udev);
1250         if (err < 0) {
1251                 dev_err(&udev->dev, "can't read configurations, error %d\n",
1252                         err);
1253                 goto fail;
1254         }
1255
1256         /* read the standard strings and cache them if present */
1257         udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1258         udev->manufacturer = usb_cache_string(udev,
1259                         udev->descriptor.iManufacturer);
1260         udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1261
1262         /* Tell the world! */
1263         dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1264                         "SerialNumber=%d\n",
1265                         udev->descriptor.iManufacturer,
1266                         udev->descriptor.iProduct,
1267                         udev->descriptor.iSerialNumber);
1268         show_string(udev, "Product", udev->product);
1269         show_string(udev, "Manufacturer", udev->manufacturer);
1270         show_string(udev, "SerialNumber", udev->serial);
1271
1272 #ifdef  CONFIG_USB_OTG
1273         /*
1274          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1275          * to wake us after we've powered off VBUS; and HNP, switching roles
1276          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1277          */
1278         if (!udev->bus->is_b_host
1279                         && udev->config
1280                         && udev->parent == udev->bus->root_hub) {
1281                 struct usb_otg_descriptor       *desc = 0;
1282                 struct usb_bus                  *bus = udev->bus;
1283
1284                 /* descriptor may appear anywhere in config */
1285                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1286                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1287                                         USB_DT_OTG, (void **) &desc) == 0) {
1288                         if (desc->bmAttributes & USB_OTG_HNP) {
1289                                 unsigned                port1 = udev->portnum;
1290
1291                                 dev_info(&udev->dev,
1292                                         "Dual-Role OTG device on %sHNP port\n",
1293                                         (port1 == bus->otg_port)
1294                                                 ? "" : "non-");
1295
1296                                 /* enable HNP before suspend, it's simpler */
1297                                 if (port1 == bus->otg_port)
1298                                         bus->b_hnp_enable = 1;
1299                                 err = usb_control_msg(udev,
1300                                         usb_sndctrlpipe(udev, 0),
1301                                         USB_REQ_SET_FEATURE, 0,
1302                                         bus->b_hnp_enable
1303                                                 ? USB_DEVICE_B_HNP_ENABLE
1304                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1305                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1306                                 if (err < 0) {
1307                                         /* OTG MESSAGE: report errors here,
1308                                          * customize to match your product.
1309                                          */
1310                                         dev_info(&udev->dev,
1311                                                 "can't set HNP mode; %d\n",
1312                                                 err);
1313                                         bus->b_hnp_enable = 0;
1314                                 }
1315                         }
1316                 }
1317         }
1318
1319         if (!is_targeted(udev)) {
1320
1321                 /* Maybe it can talk to us, though we can't talk to it.
1322                  * (Includes HNP test device.)
1323                  */
1324                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1325                         err = usb_port_suspend(udev);
1326                         if (err < 0)
1327                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1328                 }
1329                 err = -ENOTSUPP;
1330                 goto fail;
1331         }
1332 #endif
1333
1334         /* export the usbdev device-node for libusb */
1335         udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
1336                         (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
1337
1338         /* Increment the parent's count of unsuspended children */
1339         if (udev->parent)
1340                 usb_autoresume_device(udev->parent);
1341
1342         /* Register the device.  The device driver is responsible
1343          * for adding the device files to sysfs and for configuring
1344          * the device.
1345          */
1346         err = device_add(&udev->dev);
1347         if (err) {
1348                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1349                 if (udev->parent)
1350                         usb_autosuspend_device(udev->parent);
1351                 goto fail;
1352         }
1353
1354 exit:
1355         return err;
1356
1357 fail:
1358         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1359         goto exit;
1360 }
1361
1362 static int hub_port_status(struct usb_hub *hub, int port1,
1363                                u16 *status, u16 *change)
1364 {
1365         int ret;
1366
1367         mutex_lock(&hub->status_mutex);
1368         ret = get_port_status(hub->hdev, port1, &hub->status->port);
1369         if (ret < 4) {
1370                 dev_err (hub->intfdev,
1371                         "%s failed (err = %d)\n", __FUNCTION__, ret);
1372                 if (ret >= 0)
1373                         ret = -EIO;
1374         } else {
1375                 *status = le16_to_cpu(hub->status->port.wPortStatus);
1376                 *change = le16_to_cpu(hub->status->port.wPortChange);
1377                 ret = 0;
1378         }
1379         mutex_unlock(&hub->status_mutex);
1380         return ret;
1381 }
1382
1383
1384 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
1385 static unsigned hub_is_wusb(struct usb_hub *hub)
1386 {
1387         struct usb_hcd *hcd;
1388         if (hub->hdev->parent != NULL)  /* not a root hub? */
1389                 return 0;
1390         hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
1391         return hcd->wireless;
1392 }
1393
1394
1395 #define PORT_RESET_TRIES        5
1396 #define SET_ADDRESS_TRIES       2
1397 #define GET_DESCRIPTOR_TRIES    2
1398 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1399 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1400
1401 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1402 #define HUB_SHORT_RESET_TIME    10
1403 #define HUB_LONG_RESET_TIME     200
1404 #define HUB_RESET_TIMEOUT       500
1405
1406 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1407                                 struct usb_device *udev, unsigned int delay)
1408 {
1409         int delay_time, ret;
1410         u16 portstatus;
1411         u16 portchange;
1412
1413         for (delay_time = 0;
1414                         delay_time < HUB_RESET_TIMEOUT;
1415                         delay_time += delay) {
1416                 /* wait to give the device a chance to reset */
1417                 msleep(delay);
1418
1419                 /* read and decode port status */
1420                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1421                 if (ret < 0)
1422                         return ret;
1423
1424                 /* Device went away? */
1425                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1426                         return -ENOTCONN;
1427
1428                 /* bomb out completely if the connection bounced */
1429                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1430                         return -ENOTCONN;
1431
1432                 /* if we`ve finished resetting, then break out of the loop */
1433                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1434                     (portstatus & USB_PORT_STAT_ENABLE)) {
1435                         if (hub_is_wusb(hub))
1436                                 udev->speed = USB_SPEED_VARIABLE;
1437                         else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1438                                 udev->speed = USB_SPEED_HIGH;
1439                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1440                                 udev->speed = USB_SPEED_LOW;
1441                         else
1442                                 udev->speed = USB_SPEED_FULL;
1443                         return 0;
1444                 }
1445
1446                 /* switch to the long delay after two short delay failures */
1447                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1448                         delay = HUB_LONG_RESET_TIME;
1449
1450                 dev_dbg (hub->intfdev,
1451                         "port %d not reset yet, waiting %dms\n",
1452                         port1, delay);
1453         }
1454
1455         return -EBUSY;
1456 }
1457
1458 static int hub_port_reset(struct usb_hub *hub, int port1,
1459                                 struct usb_device *udev, unsigned int delay)
1460 {
1461         int i, status;
1462
1463         /* Reset the port */
1464         for (i = 0; i < PORT_RESET_TRIES; i++) {
1465                 status = set_port_feature(hub->hdev,
1466                                 port1, USB_PORT_FEAT_RESET);
1467                 if (status)
1468                         dev_err(hub->intfdev,
1469                                         "cannot reset port %d (err = %d)\n",
1470                                         port1, status);
1471                 else {
1472                         status = hub_port_wait_reset(hub, port1, udev, delay);
1473                         if (status && status != -ENOTCONN)
1474                                 dev_dbg(hub->intfdev,
1475                                                 "port_wait_reset: err = %d\n",
1476                                                 status);
1477                 }
1478
1479                 /* return on disconnect or reset */
1480                 switch (status) {
1481                 case 0:
1482                         /* TRSTRCY = 10 ms; plus some extra */
1483                         msleep(10 + 40);
1484                         udev->devnum = 0;       /* Device now at address 0 */
1485                         /* FALL THROUGH */
1486                 case -ENOTCONN:
1487                 case -ENODEV:
1488                         clear_port_feature(hub->hdev,
1489                                 port1, USB_PORT_FEAT_C_RESET);
1490                         /* FIXME need disconnect() for NOTATTACHED device */
1491                         usb_set_device_state(udev, status
1492                                         ? USB_STATE_NOTATTACHED
1493                                         : USB_STATE_DEFAULT);
1494                         return status;
1495                 }
1496
1497                 dev_dbg (hub->intfdev,
1498                         "port %d not enabled, trying reset again...\n",
1499                         port1);
1500                 delay = HUB_LONG_RESET_TIME;
1501         }
1502
1503         dev_err (hub->intfdev,
1504                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1505                 port1);
1506
1507         return status;
1508 }
1509
1510 #ifdef  CONFIG_PM
1511
1512 #ifdef  CONFIG_USB_SUSPEND
1513
1514 /*
1515  * usb_port_suspend - suspend a usb device's upstream port
1516  * @udev: device that's no longer in active use, not a root hub
1517  * Context: must be able to sleep; device not locked; pm locks held
1518  *
1519  * Suspends a USB device that isn't in active use, conserving power.
1520  * Devices may wake out of a suspend, if anything important happens,
1521  * using the remote wakeup mechanism.  They may also be taken out of
1522  * suspend by the host, using usb_port_resume().  It's also routine
1523  * to disconnect devices while they are suspended.
1524  *
1525  * This only affects the USB hardware for a device; its interfaces
1526  * (and, for hubs, child devices) must already have been suspended.
1527  *
1528  * Selective port suspend reduces power; most suspended devices draw
1529  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1530  * All devices below the suspended port are also suspended.
1531  *
1532  * Devices leave suspend state when the host wakes them up.  Some devices
1533  * also support "remote wakeup", where the device can activate the USB
1534  * tree above them to deliver data, such as a keypress or packet.  In
1535  * some cases, this wakes the USB host.
1536  *
1537  * Suspending OTG devices may trigger HNP, if that's been enabled
1538  * between a pair of dual-role devices.  That will change roles, such
1539  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1540  *
1541  * Devices on USB hub ports have only one "suspend" state, corresponding
1542  * to ACPI D2, "may cause the device to lose some context".
1543  * State transitions include:
1544  *
1545  *   - suspend, resume ... when the VBUS power link stays live
1546  *   - suspend, disconnect ... VBUS lost
1547  *
1548  * Once VBUS drop breaks the circuit, the port it's using has to go through
1549  * normal re-enumeration procedures, starting with enabling VBUS power.
1550  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1551  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1552  * timer, no SRP, no requests through sysfs.
1553  *
1554  * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1555  * the root hub for their bus goes into global suspend ... so we don't
1556  * (falsely) update the device power state to say it suspended.
1557  *
1558  * Returns 0 on success, else negative errno.
1559  */
1560 int usb_port_suspend(struct usb_device *udev)
1561 {
1562         struct usb_hub  *hub = hdev_to_hub(udev->parent);
1563         int             port1 = udev->portnum;
1564         int             status;
1565
1566         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1567
1568         /* enable remote wakeup when appropriate; this lets the device
1569          * wake up the upstream hub (including maybe the root hub).
1570          *
1571          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1572          * we don't explicitly enable it here.
1573          */
1574         if (udev->do_remote_wakeup) {
1575                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1576                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1577                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1578                                 NULL, 0,
1579                                 USB_CTRL_SET_TIMEOUT);
1580                 if (status)
1581                         dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
1582                                         status);
1583         }
1584
1585         /* see 7.1.7.6 */
1586         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1587         if (status) {
1588                 dev_dbg(hub->intfdev, "can't suspend port %d, status %d\n",
1589                                 port1, status);
1590                 /* paranoia:  "should not happen" */
1591                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1592                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1593                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1594                                 NULL, 0,
1595                                 USB_CTRL_SET_TIMEOUT);
1596         } else {
1597                 /* device has up to 10 msec to fully suspend */
1598                 dev_dbg(&udev->dev, "usb %ssuspend\n",
1599                                 udev->auto_pm ? "auto-" : "");
1600                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1601                 msleep(10);
1602         }
1603         return status;
1604 }
1605
1606 /*
1607  * If the USB "suspend" state is in use (rather than "global suspend"),
1608  * many devices will be individually taken out of suspend state using
1609  * special "resume" signaling.  This routine kicks in shortly after
1610  * hardware resume signaling is finished, either because of selective
1611  * resume (by host) or remote wakeup (by device) ... now see what changed
1612  * in the tree that's rooted at this device.
1613  *
1614  * If @udev->reset_resume is set then the device is reset before the
1615  * status check is done.
1616  */
1617 static int finish_port_resume(struct usb_device *udev)
1618 {
1619         int     status = 0;
1620         u16     devstatus;
1621
1622         /* caller owns the udev device lock */
1623         dev_dbg(&udev->dev, "finish %sresume\n",
1624                         udev->reset_resume ? "reset-" : "");
1625
1626         /* usb ch9 identifies four variants of SUSPENDED, based on what
1627          * state the device resumes to.  Linux currently won't see the
1628          * first two on the host side; they'd be inside hub_port_init()
1629          * during many timeouts, but khubd can't suspend until later.
1630          */
1631         usb_set_device_state(udev, udev->actconfig
1632                         ? USB_STATE_CONFIGURED
1633                         : USB_STATE_ADDRESS);
1634
1635         /* 10.5.4.5 says not to reset a suspended port if the attached
1636          * device is enabled for remote wakeup.  Hence the reset
1637          * operation is carried out here, after the port has been
1638          * resumed.
1639          */
1640         if (udev->reset_resume)
1641                 status = usb_reset_device(udev);
1642
1643         /* 10.5.4.5 says be sure devices in the tree are still there.
1644          * For now let's assume the device didn't go crazy on resume,
1645          * and device drivers will know about any resume quirks.
1646          */
1647         if (status == 0) {
1648                 devstatus = 0;
1649                 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1650                 if (status >= 0)
1651                         status = (status > 0 ? 0 : -ENODEV);
1652         }
1653
1654         if (status) {
1655                 dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
1656                                 status);
1657         } else if (udev->actconfig) {
1658                 le16_to_cpus(&devstatus);
1659                 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
1660                         status = usb_control_msg(udev,
1661                                         usb_sndctrlpipe(udev, 0),
1662                                         USB_REQ_CLEAR_FEATURE,
1663                                                 USB_RECIP_DEVICE,
1664                                         USB_DEVICE_REMOTE_WAKEUP, 0,
1665                                         NULL, 0,
1666                                         USB_CTRL_SET_TIMEOUT);
1667                         if (status)
1668                                 dev_dbg(&udev->dev, "disable remote "
1669                                         "wakeup, status %d\n", status);
1670                 }
1671                 status = 0;
1672         }
1673         return status;
1674 }
1675
1676 /*
1677  * usb_port_resume - re-activate a suspended usb device's upstream port
1678  * @udev: device to re-activate, not a root hub
1679  * Context: must be able to sleep; device not locked; pm locks held
1680  *
1681  * This will re-activate the suspended device, increasing power usage
1682  * while letting drivers communicate again with its endpoints.
1683  * USB resume explicitly guarantees that the power session between
1684  * the host and the device is the same as it was when the device
1685  * suspended.
1686  *
1687  * If CONFIG_USB_PERSIST and @udev->reset_resume are both set then this
1688  * routine won't check that the port is still enabled.  Furthermore,
1689  * if @udev->reset_resume is set then finish_port_resume() above will
1690  * reset @udev.  The end result is that a broken power session can be
1691  * recovered and @udev will appear to persist across a loss of VBUS power.
1692  *
1693  * For example, if a host controller doesn't maintain VBUS suspend current
1694  * during a system sleep or is reset when the system wakes up, all the USB
1695  * power sessions below it will be broken.  This is especially troublesome
1696  * for mass-storage devices containing mounted filesystems, since the
1697  * device will appear to have disconnected and all the memory mappings
1698  * to it will be lost.  Using the USB_PERSIST facility, the device can be
1699  * made to appear as if it had not disconnected.
1700  *
1701  * This facility is inherently dangerous.  Although usb_reset_device()
1702  * makes every effort to insure that the same device is present after the
1703  * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
1704  * quite possible for a device to remain unaltered but its media to be
1705  * changed.  If the user replaces a flash memory card while the system is
1706  * asleep, he will have only himself to blame when the filesystem on the
1707  * new card is corrupted and the system crashes.
1708  *
1709  * Returns 0 on success, else negative errno.
1710  */
1711 int usb_port_resume(struct usb_device *udev)
1712 {
1713         struct usb_hub  *hub = hdev_to_hub(udev->parent);
1714         int             port1 = udev->portnum;
1715         int             status;
1716         u16             portchange, portstatus;
1717         unsigned        mask_flags, want_flags;
1718
1719         /* Skip the initial Clear-Suspend step for a remote wakeup */
1720         status = hub_port_status(hub, port1, &portstatus, &portchange);
1721         if (status == 0 && !(portstatus & USB_PORT_STAT_SUSPEND))
1722                 goto SuspendCleared;
1723
1724         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1725
1726         set_bit(port1, hub->busy_bits);
1727
1728         /* see 7.1.7.7; affects power usage, but not budgeting */
1729         status = clear_port_feature(hub->hdev,
1730                         port1, USB_PORT_FEAT_SUSPEND);
1731         if (status) {
1732                 dev_dbg(hub->intfdev, "can't resume port %d, status %d\n",
1733                                 port1, status);
1734         } else {
1735                 /* drive resume for at least 20 msec */
1736                 dev_dbg(&udev->dev, "usb %sresume\n",
1737                                 udev->auto_pm ? "auto-" : "");
1738                 msleep(25);
1739
1740                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1741                  * stop resume signaling.  Then finish the resume
1742                  * sequence.
1743                  */
1744                 status = hub_port_status(hub, port1, &portstatus, &portchange);
1745
1746  SuspendCleared:
1747                 if (USB_PERSIST && udev->reset_resume)
1748                         want_flags = USB_PORT_STAT_POWER
1749                                         | USB_PORT_STAT_CONNECTION;
1750                 else
1751                         want_flags = USB_PORT_STAT_POWER
1752                                         | USB_PORT_STAT_CONNECTION
1753                                         | USB_PORT_STAT_ENABLE;
1754                 mask_flags = want_flags | USB_PORT_STAT_SUSPEND;
1755
1756                 if (status < 0 || (portstatus & mask_flags) != want_flags) {
1757                         dev_dbg(hub->intfdev,
1758                                 "port %d status %04x.%04x after resume, %d\n",
1759                                 port1, portchange, portstatus, status);
1760                         if (status >= 0)
1761                                 status = -ENODEV;
1762                 } else {
1763                         if (portchange & USB_PORT_STAT_C_SUSPEND)
1764                                 clear_port_feature(hub->hdev, port1,
1765                                                 USB_PORT_FEAT_C_SUSPEND);
1766                         /* TRSMRCY = 10 msec */
1767                         msleep(10);
1768                 }
1769         }
1770
1771         clear_bit(port1, hub->busy_bits);
1772         if (!hub->hdev->parent && !hub->busy_bits[0])
1773                 usb_enable_root_hub_irq(hub->hdev->bus);
1774
1775         if (status == 0)
1776                 status = finish_port_resume(udev);
1777         if (status < 0) {
1778                 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
1779                 hub_port_logical_disconnect(hub, port1);
1780         }
1781         return status;
1782 }
1783
1784 static int remote_wakeup(struct usb_device *udev)
1785 {
1786         int     status = 0;
1787
1788         usb_lock_device(udev);
1789         if (udev->state == USB_STATE_SUSPENDED) {
1790                 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
1791                 usb_mark_last_busy(udev);
1792                 status = usb_external_resume_device(udev);
1793         }
1794         usb_unlock_device(udev);
1795         return status;
1796 }
1797
1798 #else   /* CONFIG_USB_SUSPEND */
1799
1800 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
1801
1802 int usb_port_suspend(struct usb_device *udev)
1803 {
1804         return 0;
1805 }
1806
1807 int usb_port_resume(struct usb_device *udev)
1808 {
1809         int status = 0;
1810
1811         /* However we may need to do a reset-resume */
1812         if (udev->reset_resume) {
1813                 dev_dbg(&udev->dev, "reset-resume\n");
1814                 status = usb_reset_device(udev);
1815         }
1816         return status;
1817 }
1818
1819 static inline int remote_wakeup(struct usb_device *udev)
1820 {
1821         return 0;
1822 }
1823
1824 #endif
1825
1826 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
1827 {
1828         struct usb_hub          *hub = usb_get_intfdata (intf);
1829         struct usb_device       *hdev = hub->hdev;
1830         unsigned                port1;
1831
1832         /* fail if children aren't already suspended */
1833         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1834                 struct usb_device       *udev;
1835
1836                 udev = hdev->children [port1-1];
1837                 if (udev && msg.event == PM_EVENT_SUSPEND &&
1838 #ifdef  CONFIG_USB_SUSPEND
1839                                 udev->state != USB_STATE_SUSPENDED
1840 #else
1841                                 udev->dev.power.power_state.event
1842                                         == PM_EVENT_ON
1843 #endif
1844                                 ) {
1845                         if (!hdev->auto_pm)
1846                                 dev_dbg(&intf->dev, "port %d nyet suspended\n",
1847                                                 port1);
1848                         return -EBUSY;
1849                 }
1850         }
1851
1852         dev_dbg(&intf->dev, "%s\n", __FUNCTION__);
1853
1854         /* stop khubd and related activity */
1855         hub_quiesce(hub);
1856         return 0;
1857 }
1858
1859 static int hub_resume(struct usb_interface *intf)
1860 {
1861         struct usb_hub          *hub = usb_get_intfdata (intf);
1862
1863         dev_dbg(&intf->dev, "%s\n", __FUNCTION__);
1864
1865         /* tell khubd to look for changes on this hub */
1866         hub_activate(hub);
1867         return 0;
1868 }
1869
1870 static int hub_reset_resume(struct usb_interface *intf)
1871 {
1872         struct usb_hub *hub = usb_get_intfdata(intf);
1873         struct usb_device *hdev = hub->hdev;
1874         int port1;
1875
1876         hub_power_on(hub);
1877
1878         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
1879                 struct usb_device *child = hdev->children[port1-1];
1880
1881                 if (child) {
1882
1883                         /* For "USB_PERSIST"-enabled children we must
1884                          * mark the child device for reset-resume and
1885                          * turn off the connect-change status to prevent
1886                          * khubd from disconnecting it later.
1887                          */
1888                         if (USB_PERSIST && child->persist_enabled) {
1889                                 child->reset_resume = 1;
1890                                 clear_port_feature(hdev, port1,
1891                                                 USB_PORT_FEAT_C_CONNECTION);
1892
1893                         /* Otherwise we must disconnect the child,
1894                          * but as we may not lock the child device here
1895                          * we have to do a "logical" disconnect.
1896                          */
1897                         } else {
1898                                 hub_port_logical_disconnect(hub, port1);
1899                         }
1900                 }
1901         }
1902
1903         hub_activate(hub);
1904         return 0;
1905 }
1906
1907 /**
1908  * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
1909  * @rhdev: struct usb_device for the root hub
1910  *
1911  * The USB host controller driver calls this function when its root hub
1912  * is resumed and Vbus power has been interrupted or the controller
1913  * has been reset.  The routine marks @rhdev as having lost power.  When
1914  * the hub driver is resumed it will take notice; if CONFIG_USB_PERSIST
1915  * is enabled then it will carry out power-session recovery, otherwise
1916  * it will disconnect all the child devices.
1917  */
1918 void usb_root_hub_lost_power(struct usb_device *rhdev)
1919 {
1920         dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
1921         rhdev->reset_resume = 1;
1922 }
1923 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
1924
1925 #else   /* CONFIG_PM */
1926
1927 static inline int remote_wakeup(struct usb_device *udev)
1928 {
1929         return 0;
1930 }
1931
1932 #define hub_suspend             NULL
1933 #define hub_resume              NULL
1934 #define hub_reset_resume        NULL
1935 #endif
1936
1937
1938 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
1939  *
1940  * Between connect detection and reset signaling there must be a delay
1941  * of 100ms at least for debounce and power-settling.  The corresponding
1942  * timer shall restart whenever the downstream port detects a disconnect.
1943  *
1944  * Apparently there are some bluetooth and irda-dongles and a number of
1945  * low-speed devices for which this debounce period may last over a second.
1946  * Not covered by the spec - but easy to deal with.
1947  *
1948  * This implementation uses a 1500ms total debounce timeout; if the
1949  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
1950  * every 25ms for transient disconnects.  When the port status has been
1951  * unchanged for 100ms it returns the port status.
1952  */
1953
1954 #define HUB_DEBOUNCE_TIMEOUT    1500
1955 #define HUB_DEBOUNCE_STEP         25
1956 #define HUB_DEBOUNCE_STABLE      100
1957
1958 static int hub_port_debounce(struct usb_hub *hub, int port1)
1959 {
1960         int ret;
1961         int total_time, stable_time = 0;
1962         u16 portchange, portstatus;
1963         unsigned connection = 0xffff;
1964
1965         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
1966                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1967                 if (ret < 0)
1968                         return ret;
1969
1970                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
1971                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
1972                         stable_time += HUB_DEBOUNCE_STEP;
1973                         if (stable_time >= HUB_DEBOUNCE_STABLE)
1974                                 break;
1975                 } else {
1976                         stable_time = 0;
1977                         connection = portstatus & USB_PORT_STAT_CONNECTION;
1978                 }
1979
1980                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
1981                         clear_port_feature(hub->hdev, port1,
1982                                         USB_PORT_FEAT_C_CONNECTION);
1983                 }
1984
1985                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
1986                         break;
1987                 msleep(HUB_DEBOUNCE_STEP);
1988         }
1989
1990         dev_dbg (hub->intfdev,
1991                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
1992                 port1, total_time, stable_time, portstatus);
1993
1994         if (stable_time < HUB_DEBOUNCE_STABLE)
1995                 return -ETIMEDOUT;
1996         return portstatus;
1997 }
1998
1999 static void ep0_reinit(struct usb_device *udev)
2000 {
2001         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2002         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2003         usb_enable_endpoint(udev, &udev->ep0);
2004 }
2005
2006 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2007 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2008
2009 static int hub_set_address(struct usb_device *udev, int devnum)
2010 {
2011         int retval;
2012
2013         if (devnum <= 1)
2014                 return -EINVAL;
2015         if (udev->state == USB_STATE_ADDRESS)
2016                 return 0;
2017         if (udev->state != USB_STATE_DEFAULT)
2018                 return -EINVAL;
2019         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2020                 USB_REQ_SET_ADDRESS, 0, devnum, 0,
2021                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2022         if (retval == 0) {
2023                 udev->devnum = devnum;  /* Device now using proper address */
2024                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2025                 ep0_reinit(udev);
2026         }
2027         return retval;
2028 }
2029
2030 /* Reset device, (re)assign address, get device descriptor.
2031  * Device connection must be stable, no more debouncing needed.
2032  * Returns device in USB_STATE_ADDRESS, except on error.
2033  *
2034  * If this is called for an already-existing device (as part of
2035  * usb_reset_device), the caller must own the device lock.  For a
2036  * newly detected device that is not accessible through any global
2037  * pointers, it's not necessary to lock the device.
2038  */
2039 static int
2040 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2041                 int retry_counter)
2042 {
2043         static DEFINE_MUTEX(usb_address0_mutex);
2044
2045         struct usb_device       *hdev = hub->hdev;
2046         int                     i, j, retval;
2047         unsigned                delay = HUB_SHORT_RESET_TIME;
2048         enum usb_device_speed   oldspeed = udev->speed;
2049         char                    *speed, *type;
2050         int                     devnum = udev->devnum;
2051
2052         /* root hub ports have a slightly longer reset period
2053          * (from USB 2.0 spec, section 7.1.7.5)
2054          */
2055         if (!hdev->parent) {
2056                 delay = HUB_ROOT_RESET_TIME;
2057                 if (port1 == hdev->bus->otg_port)
2058                         hdev->bus->b_hnp_enable = 0;
2059         }
2060
2061         /* Some low speed devices have problems with the quick delay, so */
2062         /*  be a bit pessimistic with those devices. RHbug #23670 */
2063         if (oldspeed == USB_SPEED_LOW)
2064                 delay = HUB_LONG_RESET_TIME;
2065
2066         mutex_lock(&usb_address0_mutex);
2067
2068         /* Reset the device; full speed may morph to high speed */
2069         retval = hub_port_reset(hub, port1, udev, delay);
2070         if (retval < 0)         /* error or disconnect */
2071                 goto fail;
2072                                 /* success, speed is known */
2073         retval = -ENODEV;
2074
2075         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2076                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2077                 goto fail;
2078         }
2079         oldspeed = udev->speed;
2080
2081         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2082          * it's fixed size except for full speed devices.
2083          * For Wireless USB devices, ep0 max packet is always 512 (tho
2084          * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
2085          */
2086         switch (udev->speed) {
2087         case USB_SPEED_VARIABLE:        /* fixed at 512 */
2088                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(512);
2089                 break;
2090         case USB_SPEED_HIGH:            /* fixed at 64 */
2091                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2092                 break;
2093         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2094                 /* to determine the ep0 maxpacket size, try to read
2095                  * the device descriptor to get bMaxPacketSize0 and
2096                  * then correct our initial guess.
2097                  */
2098                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2099                 break;
2100         case USB_SPEED_LOW:             /* fixed at 8 */
2101                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2102                 break;
2103         default:
2104                 goto fail;
2105         }
2106
2107         type = "";
2108         switch (udev->speed) {
2109         case USB_SPEED_LOW:     speed = "low";  break;
2110         case USB_SPEED_FULL:    speed = "full"; break;
2111         case USB_SPEED_HIGH:    speed = "high"; break;
2112         case USB_SPEED_VARIABLE:
2113                                 speed = "variable";
2114                                 type = "Wireless ";
2115                                 break;
2116         default:                speed = "?";    break;
2117         }
2118         dev_info (&udev->dev,
2119                   "%s %s speed %sUSB device using %s and address %d\n",
2120                   (udev->config) ? "reset" : "new", speed, type,
2121                   udev->bus->controller->driver->name, devnum);
2122
2123         /* Set up TT records, if needed  */
2124         if (hdev->tt) {
2125                 udev->tt = hdev->tt;
2126                 udev->ttport = hdev->ttport;
2127         } else if (udev->speed != USB_SPEED_HIGH
2128                         && hdev->speed == USB_SPEED_HIGH) {
2129                 udev->tt = &hub->tt;
2130                 udev->ttport = port1;
2131         }
2132
2133         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2134          * Because device hardware and firmware is sometimes buggy in
2135          * this area, and this is how Linux has done it for ages.
2136          * Change it cautiously.
2137          *
2138          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2139          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2140          * so it may help with some non-standards-compliant devices.
2141          * Otherwise we start with SET_ADDRESS and then try to read the
2142          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2143          * value.
2144          */
2145         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2146                 if (USE_NEW_SCHEME(retry_counter)) {
2147                         struct usb_device_descriptor *buf;
2148                         int r = 0;
2149
2150 #define GET_DESCRIPTOR_BUFSIZE  64
2151                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2152                         if (!buf) {
2153                                 retval = -ENOMEM;
2154                                 continue;
2155                         }
2156
2157                         /* Retry on all errors; some devices are flakey.
2158                          * 255 is for WUSB devices, we actually need to use
2159                          * 512 (WUSB1.0[4.8.1]).
2160                          */
2161                         for (j = 0; j < 3; ++j) {
2162                                 buf->bMaxPacketSize0 = 0;
2163                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2164                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2165                                         USB_DT_DEVICE << 8, 0,
2166                                         buf, GET_DESCRIPTOR_BUFSIZE,
2167                                         USB_CTRL_GET_TIMEOUT);
2168                                 switch (buf->bMaxPacketSize0) {
2169                                 case 8: case 16: case 32: case 64: case 255:
2170                                         if (buf->bDescriptorType ==
2171                                                         USB_DT_DEVICE) {
2172                                                 r = 0;
2173                                                 break;
2174                                         }
2175                                         /* FALL THROUGH */
2176                                 default:
2177                                         if (r == 0)
2178                                                 r = -EPROTO;
2179                                         break;
2180                                 }
2181                                 if (r == 0)
2182                                         break;
2183                         }
2184                         udev->descriptor.bMaxPacketSize0 =
2185                                         buf->bMaxPacketSize0;
2186                         kfree(buf);
2187
2188                         retval = hub_port_reset(hub, port1, udev, delay);
2189                         if (retval < 0)         /* error or disconnect */
2190                                 goto fail;
2191                         if (oldspeed != udev->speed) {
2192                                 dev_dbg(&udev->dev,
2193                                         "device reset changed speed!\n");
2194                                 retval = -ENODEV;
2195                                 goto fail;
2196                         }
2197                         if (r) {
2198                                 dev_err(&udev->dev, "device descriptor "
2199                                                 "read/%s, error %d\n",
2200                                                 "64", r);
2201                                 retval = -EMSGSIZE;
2202                                 continue;
2203                         }
2204 #undef GET_DESCRIPTOR_BUFSIZE
2205                 }
2206
2207                 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2208                         retval = hub_set_address(udev, devnum);
2209                         if (retval >= 0)
2210                                 break;
2211                         msleep(200);
2212                 }
2213                 if (retval < 0) {
2214                         dev_err(&udev->dev,
2215                                 "device not accepting address %d, error %d\n",
2216                                 devnum, retval);
2217                         goto fail;
2218                 }
2219
2220                 /* cope with hardware quirkiness:
2221                  *  - let SET_ADDRESS settle, some device hardware wants it
2222                  *  - read ep0 maxpacket even for high and low speed,
2223                  */
2224                 msleep(10);
2225                 if (USE_NEW_SCHEME(retry_counter))
2226                         break;
2227
2228                 retval = usb_get_device_descriptor(udev, 8);
2229                 if (retval < 8) {
2230                         dev_err(&udev->dev, "device descriptor "
2231                                         "read/%s, error %d\n",
2232                                         "8", retval);
2233                         if (retval >= 0)
2234                                 retval = -EMSGSIZE;
2235                 } else {
2236                         retval = 0;
2237                         break;
2238                 }
2239         }
2240         if (retval)
2241                 goto fail;
2242
2243         i = udev->descriptor.bMaxPacketSize0 == 0xff?
2244             512 : udev->descriptor.bMaxPacketSize0;
2245         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2246                 if (udev->speed != USB_SPEED_FULL ||
2247                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2248                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2249                         retval = -EMSGSIZE;
2250                         goto fail;
2251                 }
2252                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2253                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2254                 ep0_reinit(udev);
2255         }
2256
2257         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2258         if (retval < (signed)sizeof(udev->descriptor)) {
2259                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2260                         "all", retval);
2261                 if (retval >= 0)
2262                         retval = -ENOMSG;
2263                 goto fail;
2264         }
2265
2266         retval = 0;
2267
2268 fail:
2269         if (retval) {
2270                 hub_port_disable(hub, port1, 0);
2271                 udev->devnum = devnum;  /* for disconnect processing */
2272         }
2273         mutex_unlock(&usb_address0_mutex);
2274         return retval;
2275 }
2276
2277 static void
2278 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2279 {
2280         struct usb_qualifier_descriptor *qual;
2281         int                             status;
2282
2283         qual = kmalloc (sizeof *qual, GFP_KERNEL);
2284         if (qual == NULL)
2285                 return;
2286
2287         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2288                         qual, sizeof *qual);
2289         if (status == sizeof *qual) {
2290                 dev_info(&udev->dev, "not running at top speed; "
2291                         "connect to a high speed hub\n");
2292                 /* hub LEDs are probably harder to miss than syslog */
2293                 if (hub->has_indicators) {
2294                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2295                         schedule_delayed_work (&hub->leds, 0);
2296                 }
2297         }
2298         kfree(qual);
2299 }
2300
2301 static unsigned
2302 hub_power_remaining (struct usb_hub *hub)
2303 {
2304         struct usb_device *hdev = hub->hdev;
2305         int remaining;
2306         int port1;
2307
2308         if (!hub->limited_power)
2309                 return 0;
2310
2311         remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
2312         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
2313                 struct usb_device       *udev = hdev->children[port1 - 1];
2314                 int                     delta;
2315
2316                 if (!udev)
2317                         continue;
2318
2319                 /* Unconfigured devices may not use more than 100mA,
2320                  * or 8mA for OTG ports */
2321                 if (udev->actconfig)
2322                         delta = udev->actconfig->desc.bMaxPower * 2;
2323                 else if (port1 != udev->bus->otg_port || hdev->parent)
2324                         delta = 100;
2325                 else
2326                         delta = 8;
2327                 if (delta > hub->mA_per_port)
2328                         dev_warn(&udev->dev, "%dmA is over %umA budget "
2329                                         "for port %d!\n",
2330                                         delta, hub->mA_per_port, port1);
2331                 remaining -= delta;
2332         }
2333         if (remaining < 0) {
2334                 dev_warn(hub->intfdev, "%dmA over power budget!\n",
2335                         - remaining);
2336                 remaining = 0;
2337         }
2338         return remaining;
2339 }
2340
2341 /* Handle physical or logical connection change events.
2342  * This routine is called when:
2343  *      a port connection-change occurs;
2344  *      a port enable-change occurs (often caused by EMI);
2345  *      usb_reset_device() encounters changed descriptors (as from
2346  *              a firmware download)
2347  * caller already locked the hub
2348  */
2349 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2350                                         u16 portstatus, u16 portchange)
2351 {
2352         struct usb_device *hdev = hub->hdev;
2353         struct device *hub_dev = hub->intfdev;
2354         u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2355         int status, i;
2356
2357         dev_dbg (hub_dev,
2358                 "port %d, status %04x, change %04x, %s\n",
2359                 port1, portstatus, portchange, portspeed (portstatus));
2360
2361         if (hub->has_indicators) {
2362                 set_port_led(hub, port1, HUB_LED_AUTO);
2363                 hub->indicator[port1-1] = INDICATOR_AUTO;
2364         }
2365
2366         /* Disconnect any existing devices under this port */
2367         if (hdev->children[port1-1])
2368                 usb_disconnect(&hdev->children[port1-1]);
2369         clear_bit(port1, hub->change_bits);
2370
2371 #ifdef  CONFIG_USB_OTG
2372         /* during HNP, don't repeat the debounce */
2373         if (hdev->bus->is_b_host)
2374                 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2375 #endif
2376
2377         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2378                 status = hub_port_debounce(hub, port1);
2379                 if (status < 0) {
2380                         if (printk_ratelimit())
2381                                 dev_err (hub_dev, "connect-debounce failed, "
2382                                                 "port %d disabled\n", port1);
2383                         goto done;
2384                 }
2385                 portstatus = status;
2386         }
2387
2388         /* Return now if nothing is connected */
2389         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2390
2391                 /* maybe switch power back on (e.g. root hub was reset) */
2392                 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
2393                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2394                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2395
2396                 if (portstatus & USB_PORT_STAT_ENABLE)
2397                         goto done;
2398                 return;
2399         }
2400
2401         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2402                 struct usb_device *udev;
2403
2404                 /* reallocate for each attempt, since references
2405                  * to the previous one can escape in various ways
2406                  */
2407                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2408                 if (!udev) {
2409                         dev_err (hub_dev,
2410                                 "couldn't allocate port %d usb_device\n",
2411                                 port1);
2412                         goto done;
2413                 }
2414
2415                 usb_set_device_state(udev, USB_STATE_POWERED);
2416                 udev->speed = USB_SPEED_UNKNOWN;
2417                 udev->bus_mA = hub->mA_per_port;
2418                 udev->level = hdev->level + 1;
2419
2420                 /* set the address */
2421                 choose_address(udev);
2422                 if (udev->devnum <= 0) {
2423                         status = -ENOTCONN;     /* Don't retry */
2424                         goto loop;
2425                 }
2426
2427                 /* reset and get descriptor */
2428                 status = hub_port_init(hub, udev, port1, i);
2429                 if (status < 0)
2430                         goto loop;
2431
2432                 /* consecutive bus-powered hubs aren't reliable; they can
2433                  * violate the voltage drop budget.  if the new child has
2434                  * a "powered" LED, users should notice we didn't enable it
2435                  * (without reading syslog), even without per-port LEDs
2436                  * on the parent.
2437                  */
2438                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2439                                 && udev->bus_mA <= 100) {
2440                         u16     devstat;
2441
2442                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2443                                         &devstat);
2444                         if (status < 2) {
2445                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2446                                 goto loop_disable;
2447                         }
2448                         le16_to_cpus(&devstat);
2449                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2450                                 dev_err(&udev->dev,
2451                                         "can't connect bus-powered hub "
2452                                         "to this port\n");
2453                                 if (hub->has_indicators) {
2454                                         hub->indicator[port1-1] =
2455                                                 INDICATOR_AMBER_BLINK;
2456                                         schedule_delayed_work (&hub->leds, 0);
2457                                 }
2458                                 status = -ENOTCONN;     /* Don't retry */
2459                                 goto loop_disable;
2460                         }
2461                 }
2462
2463                 /* check for devices running slower than they could */
2464                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2465                                 && udev->speed == USB_SPEED_FULL
2466                                 && highspeed_hubs != 0)
2467                         check_highspeed (hub, udev, port1);
2468
2469                 /* Store the parent's children[] pointer.  At this point
2470                  * udev becomes globally accessible, although presumably
2471                  * no one will look at it until hdev is unlocked.
2472                  */
2473                 status = 0;
2474
2475                 /* We mustn't add new devices if the parent hub has
2476                  * been disconnected; we would race with the
2477                  * recursively_mark_NOTATTACHED() routine.
2478                  */
2479                 spin_lock_irq(&device_state_lock);
2480                 if (hdev->state == USB_STATE_NOTATTACHED)
2481                         status = -ENOTCONN;
2482                 else
2483                         hdev->children[port1-1] = udev;
2484                 spin_unlock_irq(&device_state_lock);
2485
2486                 /* Run it through the hoops (find a driver, etc) */
2487                 if (!status) {
2488                         status = usb_new_device(udev);
2489                         if (status) {
2490                                 spin_lock_irq(&device_state_lock);
2491                                 hdev->children[port1-1] = NULL;
2492                                 spin_unlock_irq(&device_state_lock);
2493                         }
2494                 }
2495
2496                 if (status)
2497                         goto loop_disable;
2498
2499                 status = hub_power_remaining(hub);
2500                 if (status)
2501                         dev_dbg(hub_dev, "%dmA power budget left\n", status);
2502
2503                 return;
2504
2505 loop_disable:
2506                 hub_port_disable(hub, port1, 1);
2507 loop:
2508                 ep0_reinit(udev);
2509                 release_address(udev);
2510                 usb_put_dev(udev);
2511                 if ((status == -ENOTCONN) || (status == -ENOTSUPP))
2512                         break;
2513         }
2514
2515 done:
2516         hub_port_disable(hub, port1, 1);
2517 }
2518
2519 static void hub_events(void)
2520 {
2521         struct list_head *tmp;
2522         struct usb_device *hdev;
2523         struct usb_interface *intf;
2524         struct usb_hub *hub;
2525         struct device *hub_dev;
2526         u16 hubstatus;
2527         u16 hubchange;
2528         u16 portstatus;
2529         u16 portchange;
2530         int i, ret;
2531         int connect_change;
2532
2533         /*
2534          *  We restart the list every time to avoid a deadlock with
2535          * deleting hubs downstream from this one. This should be
2536          * safe since we delete the hub from the event list.
2537          * Not the most efficient, but avoids deadlocks.
2538          */
2539         while (1) {
2540
2541                 /* Grab the first entry at the beginning of the list */
2542                 spin_lock_irq(&hub_event_lock);
2543                 if (list_empty(&hub_event_list)) {
2544                         spin_unlock_irq(&hub_event_lock);
2545                         break;
2546                 }
2547
2548                 tmp = hub_event_list.next;
2549                 list_del_init(tmp);
2550
2551                 hub = list_entry(tmp, struct usb_hub, event_list);
2552                 kref_get(&hub->kref);
2553                 spin_unlock_irq(&hub_event_lock);
2554
2555                 hdev = hub->hdev;
2556                 hub_dev = hub->intfdev;
2557                 intf = to_usb_interface(hub_dev);
2558                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
2559                                 hdev->state, hub->descriptor
2560                                         ? hub->descriptor->bNbrPorts
2561                                         : 0,
2562                                 /* NOTE: expects max 15 ports... */
2563                                 (u16) hub->change_bits[0],
2564                                 (u16) hub->event_bits[0]);
2565
2566                 /* Lock the device, then check to see if we were
2567                  * disconnected while waiting for the lock to succeed. */
2568                 usb_lock_device(hdev);
2569                 if (unlikely(hub->disconnected))
2570                         goto loop;
2571
2572                 /* If the hub has died, clean up after it */
2573                 if (hdev->state == USB_STATE_NOTATTACHED) {
2574                         hub->error = -ENODEV;
2575                         hub_pre_reset(intf);
2576                         goto loop;
2577                 }
2578
2579                 /* Autoresume */
2580                 ret = usb_autopm_get_interface(intf);
2581                 if (ret) {
2582                         dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
2583                         goto loop;
2584                 }
2585
2586                 /* If this is an inactive hub, do nothing */
2587                 if (hub->quiescing)
2588                         goto loop_autopm;
2589
2590                 if (hub->error) {
2591                         dev_dbg (hub_dev, "resetting for error %d\n",
2592                                 hub->error);
2593
2594                         ret = usb_reset_composite_device(hdev, intf);
2595                         if (ret) {
2596                                 dev_dbg (hub_dev,
2597                                         "error resetting hub: %d\n", ret);
2598                                 goto loop_autopm;
2599                         }
2600
2601                         hub->nerrors = 0;
2602                         hub->error = 0;
2603                 }
2604
2605                 /* deal with port status changes */
2606                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2607                         if (test_bit(i, hub->busy_bits))
2608                                 continue;
2609                         connect_change = test_bit(i, hub->change_bits);
2610                         if (!test_and_clear_bit(i, hub->event_bits) &&
2611                                         !connect_change && !hub->activating)
2612                                 continue;
2613
2614                         ret = hub_port_status(hub, i,
2615                                         &portstatus, &portchange);
2616                         if (ret < 0)
2617                                 continue;
2618
2619                         if (hub->activating && !hdev->children[i-1] &&
2620                                         (portstatus &
2621                                                 USB_PORT_STAT_CONNECTION))
2622                                 connect_change = 1;
2623
2624                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2625                                 clear_port_feature(hdev, i,
2626                                         USB_PORT_FEAT_C_CONNECTION);
2627                                 connect_change = 1;
2628                         }
2629
2630                         if (portchange & USB_PORT_STAT_C_ENABLE) {
2631                                 if (!connect_change)
2632                                         dev_dbg (hub_dev,
2633                                                 "port %d enable change, "
2634                                                 "status %08x\n",
2635                                                 i, portstatus);
2636                                 clear_port_feature(hdev, i,
2637                                         USB_PORT_FEAT_C_ENABLE);
2638
2639                                 /*
2640                                  * EM interference sometimes causes badly
2641                                  * shielded USB devices to be shutdown by
2642                                  * the hub, this hack enables them again.
2643                                  * Works at least with mouse driver.
2644                                  */
2645                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
2646                                     && !connect_change
2647                                     && hdev->children[i-1]) {
2648                                         dev_err (hub_dev,
2649                                             "port %i "
2650                                             "disabled by hub (EMI?), "
2651                                             "re-enabling...\n",
2652                                                 i);
2653                                         connect_change = 1;
2654                                 }
2655                         }
2656
2657                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2658                                 clear_port_feature(hdev, i,
2659                                         USB_PORT_FEAT_C_SUSPEND);
2660                                 if (hdev->children[i-1]) {
2661                                         ret = remote_wakeup(hdev->
2662                                                         children[i-1]);
2663                                         if (ret < 0)
2664                                                 connect_change = 1;
2665                                 } else {
2666                                         ret = -ENODEV;
2667                                         hub_port_disable(hub, i, 1);
2668                                 }
2669                                 dev_dbg (hub_dev,
2670                                         "resume on port %d, status %d\n",
2671                                         i, ret);
2672                         }
2673
2674                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2675                                 dev_err (hub_dev,
2676                                         "over-current change on port %d\n",
2677                                         i);
2678                                 clear_port_feature(hdev, i,
2679                                         USB_PORT_FEAT_C_OVER_CURRENT);
2680                                 hub_power_on(hub);
2681                         }
2682
2683                         if (portchange & USB_PORT_STAT_C_RESET) {
2684                                 dev_dbg (hub_dev,
2685                                         "reset change on port %d\n",
2686                                         i);
2687                                 clear_port_feature(hdev, i,
2688                                         USB_PORT_FEAT_C_RESET);
2689                         }
2690
2691                         if (connect_change)
2692                                 hub_port_connect_change(hub, i,
2693                                                 portstatus, portchange);
2694                 } /* end for i */
2695
2696                 /* deal with hub status changes */
2697                 if (test_and_clear_bit(0, hub->event_bits) == 0)
2698                         ;       /* do nothing */
2699                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2700                         dev_err (hub_dev, "get_hub_status failed\n");
2701                 else {
2702                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2703                                 dev_dbg (hub_dev, "power change\n");
2704                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2705                                 if (hubstatus & HUB_STATUS_LOCAL_POWER)
2706                                         /* FIXME: Is this always true? */
2707                                         hub->limited_power = 0;
2708                                 else
2709                                         hub->limited_power = 1;
2710                         }
2711                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
2712                                 dev_dbg (hub_dev, "overcurrent change\n");
2713                                 msleep(500);    /* Cool down */
2714                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2715                                 hub_power_on(hub);
2716                         }
2717                 }
2718
2719                 hub->activating = 0;
2720
2721                 /* If this is a root hub, tell the HCD it's okay to
2722                  * re-enable port-change interrupts now. */
2723                 if (!hdev->parent && !hub->busy_bits[0])
2724                         usb_enable_root_hub_irq(hdev->bus);
2725
2726 loop_autopm:
2727                 /* Allow autosuspend if we're not going to run again */
2728                 if (list_empty(&hub->event_list))
2729                         usb_autopm_enable(intf);
2730 loop:
2731                 usb_unlock_device(hdev);
2732                 kref_put(&hub->kref, hub_release);
2733
2734         } /* end while (1) */
2735 }
2736
2737 static int hub_thread(void *__unused)
2738 {
2739         set_freezable();
2740         do {
2741                 hub_events();
2742                 wait_event_interruptible(khubd_wait,
2743                                 !list_empty(&hub_event_list) ||
2744                                 kthread_should_stop());
2745                 try_to_freeze();
2746         } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2747
2748         pr_debug("%s: khubd exiting\n", usbcore_name);
2749         return 0;
2750 }
2751
2752 static struct usb_device_id hub_id_table [] = {
2753     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2754       .bDeviceClass = USB_CLASS_HUB},
2755     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2756       .bInterfaceClass = USB_CLASS_HUB},
2757     { }                                         /* Terminating entry */
2758 };
2759
2760 MODULE_DEVICE_TABLE (usb, hub_id_table);
2761
2762 static struct usb_driver hub_driver = {
2763         .name =         "hub",
2764         .probe =        hub_probe,
2765         .disconnect =   hub_disconnect,
2766         .suspend =      hub_suspend,
2767         .resume =       hub_resume,
2768         .reset_resume = hub_reset_resume,
2769         .pre_reset =    hub_pre_reset,
2770         .post_reset =   hub_post_reset,
2771         .ioctl =        hub_ioctl,
2772         .id_table =     hub_id_table,
2773         .supports_autosuspend = 1,
2774 };
2775
2776 int usb_hub_init(void)
2777 {
2778         if (usb_register(&hub_driver) < 0) {
2779                 printk(KERN_ERR "%s: can't register hub driver\n",
2780                         usbcore_name);
2781                 return -1;
2782         }
2783
2784         khubd_task = kthread_run(hub_thread, NULL, "khubd");
2785         if (!IS_ERR(khubd_task))
2786                 return 0;
2787
2788         /* Fall through if kernel_thread failed */
2789         usb_deregister(&hub_driver);
2790         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2791
2792         return -1;
2793 }
2794
2795 void usb_hub_cleanup(void)
2796 {
2797         kthread_stop(khubd_task);
2798
2799         /*
2800          * Hub resources are freed for us by usb_deregister. It calls
2801          * usb_driver_purge on every device which in turn calls that
2802          * devices disconnect function if it is using this driver.
2803          * The hub_disconnect function takes care of releasing the
2804          * individual hub resources. -greg
2805          */
2806         usb_deregister(&hub_driver);
2807 } /* usb_hub_cleanup() */
2808
2809 static int config_descriptors_changed(struct usb_device *udev)
2810 {
2811         unsigned                        index;
2812         unsigned                        len = 0;
2813         struct usb_config_descriptor    *buf;
2814
2815         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2816                 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2817                         len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2818         }
2819         buf = kmalloc (len, GFP_KERNEL);
2820         if (buf == NULL) {
2821                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2822                 /* assume the worst */
2823                 return 1;
2824         }
2825         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2826                 int length;
2827                 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2828
2829                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2830                                 old_length);
2831                 if (length < old_length) {
2832                         dev_dbg(&udev->dev, "config index %d, error %d\n",
2833                                         index, length);
2834                         break;
2835                 }
2836                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2837                                 != 0) {
2838                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2839                                 index, buf->bConfigurationValue);
2840                         break;
2841                 }
2842         }
2843         kfree(buf);
2844         return index != udev->descriptor.bNumConfigurations;
2845 }
2846
2847 /**
2848  * usb_reset_device - perform a USB port reset to reinitialize a device
2849  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2850  *
2851  * WARNING - don't use this routine to reset a composite device
2852  * (one with multiple interfaces owned by separate drivers)!
2853  * Use usb_reset_composite_device() instead.
2854  *
2855  * Do a port reset, reassign the device's address, and establish its
2856  * former operating configuration.  If the reset fails, or the device's
2857  * descriptors change from their values before the reset, or the original
2858  * configuration and altsettings cannot be restored, a flag will be set
2859  * telling khubd to pretend the device has been disconnected and then
2860  * re-connected.  All drivers will be unbound, and the device will be
2861  * re-enumerated and probed all over again.
2862  *
2863  * Returns 0 if the reset succeeded, -ENODEV if the device has been
2864  * flagged for logical disconnection, or some other negative error code
2865  * if the reset wasn't even attempted.
2866  *
2867  * The caller must own the device lock.  For example, it's safe to use
2868  * this from a driver probe() routine after downloading new firmware.
2869  * For calls that might not occur during probe(), drivers should lock
2870  * the device using usb_lock_device_for_reset().
2871  *
2872  * Locking exception: This routine may also be called from within an
2873  * autoresume handler.  Such usage won't conflict with other tasks
2874  * holding the device lock because these tasks should always call
2875  * usb_autopm_resume_device(), thereby preventing any unwanted autoresume.
2876  */
2877 int usb_reset_device(struct usb_device *udev)
2878 {
2879         struct usb_device               *parent_hdev = udev->parent;
2880         struct usb_hub                  *parent_hub;
2881         struct usb_device_descriptor    descriptor = udev->descriptor;
2882         int                             i, ret = 0;
2883         int                             port1 = udev->portnum;
2884
2885         if (udev->state == USB_STATE_NOTATTACHED ||
2886                         udev->state == USB_STATE_SUSPENDED) {
2887                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2888                                 udev->state);
2889                 return -EINVAL;
2890         }
2891
2892         if (!parent_hdev) {
2893                 /* this requires hcd-specific logic; see OHCI hc_restart() */
2894                 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2895                 return -EISDIR;
2896         }
2897         parent_hub = hdev_to_hub(parent_hdev);
2898
2899         set_bit(port1, parent_hub->busy_bits);
2900         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
2901
2902                 /* ep0 maxpacket size may change; let the HCD know about it.
2903                  * Other endpoints will be handled by re-enumeration. */
2904                 ep0_reinit(udev);
2905                 ret = hub_port_init(parent_hub, udev, port1, i);
2906                 if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
2907                         break;
2908         }
2909         clear_bit(port1, parent_hub->busy_bits);
2910         if (!parent_hdev->parent && !parent_hub->busy_bits[0])
2911                 usb_enable_root_hub_irq(parent_hdev->bus);
2912
2913         if (ret < 0)
2914                 goto re_enumerate;
2915
2916         /* Device might have changed firmware (DFU or similar) */
2917         if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
2918                         || config_descriptors_changed (udev)) {
2919                 dev_info(&udev->dev, "device firmware changed\n");
2920                 udev->descriptor = descriptor;  /* for disconnect() calls */
2921                 goto re_enumerate;
2922         }
2923
2924         if (!udev->actconfig)
2925                 goto done;
2926
2927         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2928                         USB_REQ_SET_CONFIGURATION, 0,
2929                         udev->actconfig->desc.bConfigurationValue, 0,
2930                         NULL, 0, USB_CTRL_SET_TIMEOUT);
2931         if (ret < 0) {
2932                 dev_err(&udev->dev,
2933                         "can't restore configuration #%d (error=%d)\n",
2934                         udev->actconfig->desc.bConfigurationValue, ret);
2935                 goto re_enumerate;
2936         }
2937         usb_set_device_state(udev, USB_STATE_CONFIGURED);
2938
2939         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
2940                 struct usb_interface *intf = udev->actconfig->interface[i];
2941                 struct usb_interface_descriptor *desc;
2942
2943                 /* set_interface resets host side toggle even
2944                  * for altsetting zero.  the interface may have no driver.
2945                  */
2946                 desc = &intf->cur_altsetting->desc;
2947                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
2948                         desc->bAlternateSetting);
2949                 if (ret < 0) {
2950                         dev_err(&udev->dev, "failed to restore interface %d "
2951                                 "altsetting %d (error=%d)\n",
2952                                 desc->bInterfaceNumber,
2953                                 desc->bAlternateSetting,
2954                                 ret);
2955                         goto re_enumerate;
2956                 }
2957         }
2958
2959 done:
2960         return 0;
2961
2962 re_enumerate:
2963         hub_port_logical_disconnect(parent_hub, port1);
2964         return -ENODEV;
2965 }
2966 EXPORT_SYMBOL(usb_reset_device);
2967
2968 /**
2969  * usb_reset_composite_device - warn interface drivers and perform a USB port reset
2970  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2971  * @iface: interface bound to the driver making the request (optional)
2972  *
2973  * Warns all drivers bound to registered interfaces (using their pre_reset
2974  * method), performs the port reset, and then lets the drivers know that
2975  * the reset is over (using their post_reset method).
2976  *
2977  * Return value is the same as for usb_reset_device().
2978  *
2979  * The caller must own the device lock.  For example, it's safe to use
2980  * this from a driver probe() routine after downloading new firmware.
2981  * For calls that might not occur during probe(), drivers should lock
2982  * the device using usb_lock_device_for_reset().
2983  *
2984  * The interface locks are acquired during the pre_reset stage and released
2985  * during the post_reset stage.  However if iface is not NULL and is
2986  * currently being probed, we assume that the caller already owns its
2987  * lock.
2988  */
2989 int usb_reset_composite_device(struct usb_device *udev,
2990                 struct usb_interface *iface)
2991 {
2992         int ret;
2993         struct usb_host_config *config = udev->actconfig;
2994
2995         if (udev->state == USB_STATE_NOTATTACHED ||
2996                         udev->state == USB_STATE_SUSPENDED) {
2997                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2998                                 udev->state);
2999                 return -EINVAL;
3000         }
3001
3002         /* Prevent autosuspend during the reset */
3003         usb_autoresume_device(udev);
3004
3005         if (iface && iface->condition != USB_INTERFACE_BINDING)
3006                 iface = NULL;
3007
3008         if (config) {
3009                 int i;
3010                 struct usb_interface *cintf;
3011                 struct usb_driver *drv;
3012
3013                 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
3014                         cintf = config->interface[i];
3015                         if (cintf != iface)
3016                                 down(&cintf->dev.sem);
3017                         if (device_is_registered(&cintf->dev) &&
3018                                         cintf->dev.driver) {
3019                                 drv = to_usb_driver(cintf->dev.driver);
3020                                 if (drv->pre_reset)
3021                                         (drv->pre_reset)(cintf);
3022         /* FIXME: Unbind if pre_reset returns an error or isn't defined */
3023                         }
3024                 }
3025         }
3026
3027         ret = usb_reset_device(udev);
3028
3029         if (config) {
3030                 int i;
3031                 struct usb_interface *cintf;
3032                 struct usb_driver *drv;
3033
3034                 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
3035                         cintf = config->interface[i];
3036                         if (device_is_registered(&cintf->dev) &&
3037                                         cintf->dev.driver) {
3038                                 drv = to_usb_driver(cintf->dev.driver);
3039                                 if (drv->post_reset)
3040                                         (drv->post_reset)(cintf);
3041         /* FIXME: Unbind if post_reset returns an error or isn't defined */
3042                         }
3043                         if (cintf != iface)
3044                                 up(&cintf->dev.sem);
3045                 }
3046         }
3047
3048         usb_autosuspend_device(udev);
3049         return ret;
3050 }
3051 EXPORT_SYMBOL(usb_reset_composite_device);