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/uaccess.h> 27 #include <asm/byteorder.h> 28 29 #include "usb.h" 30 #include "hcd.h" 31 #include "hub.h" 32 33 /* if we are in debug mode, always announce new devices */ 34 #ifdef DEBUG 35 #ifndef CONFIG_USB_ANNOUNCE_NEW_DEVICES 36 #define CONFIG_USB_ANNOUNCE_NEW_DEVICES 37 #endif 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 union { 49 struct usb_hub_status hub; 50 struct usb_port_status port; 51 } *status; /* buffer for status reports */ 52 struct mutex status_mutex; /* for the status buffer */ 53 54 int error; /* last reported error */ 55 int nerrors; /* track consecutive errors */ 56 57 struct list_head event_list; /* hubs w/data or errs ready */ 58 unsigned long event_bits[1]; /* status change bitmask */ 59 unsigned long change_bits[1]; /* ports with logical connect 60 status change */ 61 unsigned long busy_bits[1]; /* ports being reset or 62 resumed */ 63 unsigned long removed_bits[1]; /* ports with a "removed" 64 device present */ 65 #if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */ 66 #error event_bits[] is too short! 67 #endif 68 69 struct usb_hub_descriptor *descriptor; /* class descriptor */ 70 struct usb_tt tt; /* Transaction Translator */ 71 72 unsigned mA_per_port; /* current for each child */ 73 74 unsigned init_done:1; 75 unsigned limited_power:1; 76 unsigned quiescing:1; 77 unsigned disconnected:1; 78 79 unsigned has_indicators:1; 80 u8 indicator[USB_MAXCHILDREN]; 81 struct delayed_work leds; 82 struct delayed_work init_work; 83 void **port_owners; 84 }; 85 86 87 /* Protect struct usb_device->state and ->children members 88 * Note: Both are also protected by ->dev.sem, except that ->state can 89 * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */ 90 static DEFINE_SPINLOCK(device_state_lock); 91 92 /* khubd's worklist and its lock */ 93 static DEFINE_SPINLOCK(hub_event_lock); 94 static LIST_HEAD(hub_event_list); /* List of hubs needing servicing */ 95 96 /* Wakes up khubd */ 97 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait); 98 99 static struct task_struct *khubd_task; 100 101 /* cycle leds on hubs that aren't blinking for attention */ 102 static int blinkenlights = 0; 103 module_param (blinkenlights, bool, S_IRUGO); 104 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs"); 105 106 /* 107 * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about 108 * 10 seconds to send reply for the initial 64-byte descriptor request. 109 */ 110 /* define initial 64-byte descriptor request timeout in milliseconds */ 111 static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT; 112 module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR); 113 MODULE_PARM_DESC(initial_descriptor_timeout, 114 "initial 64-byte descriptor request timeout in milliseconds " 115 "(default 5000 - 5.0 seconds)"); 116 117 /* 118 * As of 2.6.10 we introduce a new USB device initialization scheme which 119 * closely resembles the way Windows works. Hopefully it will be compatible 120 * with a wider range of devices than the old scheme. However some previously 121 * working devices may start giving rise to "device not accepting address" 122 * errors; if that happens the user can try the old scheme by adjusting the 123 * following module parameters. 124 * 125 * For maximum flexibility there are two boolean parameters to control the 126 * hub driver's behavior. On the first initialization attempt, if the 127 * "old_scheme_first" parameter is set then the old scheme will be used, 128 * otherwise the new scheme is used. If that fails and "use_both_schemes" 129 * is set, then the driver will make another attempt, using the other scheme. 130 */ 131 static int old_scheme_first = 0; 132 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR); 133 MODULE_PARM_DESC(old_scheme_first, 134 "start with the old device initialization scheme"); 135 136 static int use_both_schemes = 1; 137 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR); 138 MODULE_PARM_DESC(use_both_schemes, 139 "try the other device initialization scheme if the " 140 "first one fails"); 141 142 /* Mutual exclusion for EHCI CF initialization. This interferes with 143 * port reset on some companion controllers. 144 */ 145 DECLARE_RWSEM(ehci_cf_port_reset_rwsem); 146 EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem); 147 148 #define HUB_DEBOUNCE_TIMEOUT 1500 149 #define HUB_DEBOUNCE_STEP 25 150 #define HUB_DEBOUNCE_STABLE 100 151 152 153 static int usb_reset_and_verify_device(struct usb_device *udev); 154 155 static inline char *portspeed(int portstatus) 156 { 157 if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED)) 158 return "480 Mb/s"; 159 else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED)) 160 return "1.5 Mb/s"; 161 else if (portstatus & (1 << USB_PORT_FEAT_SUPERSPEED)) 162 return "5.0 Gb/s"; 163 else 164 return "12 Mb/s"; 165 } 166 167 /* Note that hdev or one of its children must be locked! */ 168 static struct usb_hub *hdev_to_hub(struct usb_device *hdev) 169 { 170 if (!hdev || !hdev->actconfig) 171 return NULL; 172 return usb_get_intfdata(hdev->actconfig->interface[0]); 173 } 174 175 /* USB 2.0 spec Section 11.24.4.5 */ 176 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size) 177 { 178 int i, ret; 179 180 for (i = 0; i < 3; i++) { 181 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0), 182 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB, 183 USB_DT_HUB << 8, 0, data, size, 184 USB_CTRL_GET_TIMEOUT); 185 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2)) 186 return ret; 187 } 188 return -EINVAL; 189 } 190 191 /* 192 * USB 2.0 spec Section 11.24.2.1 193 */ 194 static int clear_hub_feature(struct usb_device *hdev, int feature) 195 { 196 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0), 197 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000); 198 } 199 200 /* 201 * USB 2.0 spec Section 11.24.2.2 202 */ 203 static int clear_port_feature(struct usb_device *hdev, int port1, int feature) 204 { 205 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0), 206 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1, 207 NULL, 0, 1000); 208 } 209 210 /* 211 * USB 2.0 spec Section 11.24.2.13 212 */ 213 static int set_port_feature(struct usb_device *hdev, int port1, int feature) 214 { 215 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0), 216 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1, 217 NULL, 0, 1000); 218 } 219 220 /* 221 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7 222 * for info about using port indicators 223 */ 224 static void set_port_led( 225 struct usb_hub *hub, 226 int port1, 227 int selector 228 ) 229 { 230 int status = set_port_feature(hub->hdev, (selector << 8) | port1, 231 USB_PORT_FEAT_INDICATOR); 232 if (status < 0) 233 dev_dbg (hub->intfdev, 234 "port %d indicator %s status %d\n", 235 port1, 236 ({ char *s; switch (selector) { 237 case HUB_LED_AMBER: s = "amber"; break; 238 case HUB_LED_GREEN: s = "green"; break; 239 case HUB_LED_OFF: s = "off"; break; 240 case HUB_LED_AUTO: s = "auto"; break; 241 default: s = "??"; break; 242 }; s; }), 243 status); 244 } 245 246 #define LED_CYCLE_PERIOD ((2*HZ)/3) 247 248 static void led_work (struct work_struct *work) 249 { 250 struct usb_hub *hub = 251 container_of(work, struct usb_hub, leds.work); 252 struct usb_device *hdev = hub->hdev; 253 unsigned i; 254 unsigned changed = 0; 255 int cursor = -1; 256 257 if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing) 258 return; 259 260 for (i = 0; i < hub->descriptor->bNbrPorts; i++) { 261 unsigned selector, mode; 262 263 /* 30%-50% duty cycle */ 264 265 switch (hub->indicator[i]) { 266 /* cycle marker */ 267 case INDICATOR_CYCLE: 268 cursor = i; 269 selector = HUB_LED_AUTO; 270 mode = INDICATOR_AUTO; 271 break; 272 /* blinking green = sw attention */ 273 case INDICATOR_GREEN_BLINK: 274 selector = HUB_LED_GREEN; 275 mode = INDICATOR_GREEN_BLINK_OFF; 276 break; 277 case INDICATOR_GREEN_BLINK_OFF: 278 selector = HUB_LED_OFF; 279 mode = INDICATOR_GREEN_BLINK; 280 break; 281 /* blinking amber = hw attention */ 282 case INDICATOR_AMBER_BLINK: 283 selector = HUB_LED_AMBER; 284 mode = INDICATOR_AMBER_BLINK_OFF; 285 break; 286 case INDICATOR_AMBER_BLINK_OFF: 287 selector = HUB_LED_OFF; 288 mode = INDICATOR_AMBER_BLINK; 289 break; 290 /* blink green/amber = reserved */ 291 case INDICATOR_ALT_BLINK: 292 selector = HUB_LED_GREEN; 293 mode = INDICATOR_ALT_BLINK_OFF; 294 break; 295 case INDICATOR_ALT_BLINK_OFF: 296 selector = HUB_LED_AMBER; 297 mode = INDICATOR_ALT_BLINK; 298 break; 299 default: 300 continue; 301 } 302 if (selector != HUB_LED_AUTO) 303 changed = 1; 304 set_port_led(hub, i + 1, selector); 305 hub->indicator[i] = mode; 306 } 307 if (!changed && blinkenlights) { 308 cursor++; 309 cursor %= hub->descriptor->bNbrPorts; 310 set_port_led(hub, cursor + 1, HUB_LED_GREEN); 311 hub->indicator[cursor] = INDICATOR_CYCLE; 312 changed++; 313 } 314 if (changed) 315 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD); 316 } 317 318 /* use a short timeout for hub/port status fetches */ 319 #define USB_STS_TIMEOUT 1000 320 #define USB_STS_RETRIES 5 321 322 /* 323 * USB 2.0 spec Section 11.24.2.6 324 */ 325 static int get_hub_status(struct usb_device *hdev, 326 struct usb_hub_status *data) 327 { 328 int i, status = -ETIMEDOUT; 329 330 for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) { 331 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0), 332 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0, 333 data, sizeof(*data), USB_STS_TIMEOUT); 334 } 335 return status; 336 } 337 338 /* 339 * USB 2.0 spec Section 11.24.2.7 340 */ 341 static int get_port_status(struct usb_device *hdev, int port1, 342 struct usb_port_status *data) 343 { 344 int i, status = -ETIMEDOUT; 345 346 for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) { 347 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0), 348 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1, 349 data, sizeof(*data), USB_STS_TIMEOUT); 350 } 351 return status; 352 } 353 354 static int hub_port_status(struct usb_hub *hub, int port1, 355 u16 *status, u16 *change) 356 { 357 int ret; 358 359 mutex_lock(&hub->status_mutex); 360 ret = get_port_status(hub->hdev, port1, &hub->status->port); 361 if (ret < 4) { 362 dev_err(hub->intfdev, 363 "%s failed (err = %d)\n", __func__, ret); 364 if (ret >= 0) 365 ret = -EIO; 366 } else { 367 *status = le16_to_cpu(hub->status->port.wPortStatus); 368 *change = le16_to_cpu(hub->status->port.wPortChange); 369 ret = 0; 370 } 371 mutex_unlock(&hub->status_mutex); 372 return ret; 373 } 374 375 static void kick_khubd(struct usb_hub *hub) 376 { 377 unsigned long flags; 378 379 spin_lock_irqsave(&hub_event_lock, flags); 380 if (!hub->disconnected && list_empty(&hub->event_list)) { 381 list_add_tail(&hub->event_list, &hub_event_list); 382 383 /* Suppress autosuspend until khubd runs */ 384 usb_autopm_get_interface_no_resume( 385 to_usb_interface(hub->intfdev)); 386 wake_up(&khubd_wait); 387 } 388 spin_unlock_irqrestore(&hub_event_lock, flags); 389 } 390 391 void usb_kick_khubd(struct usb_device *hdev) 392 { 393 struct usb_hub *hub = hdev_to_hub(hdev); 394 395 if (hub) 396 kick_khubd(hub); 397 } 398 399 400 /* completion function, fires on port status changes and various faults */ 401 static void hub_irq(struct urb *urb) 402 { 403 struct usb_hub *hub = urb->context; 404 int status = urb->status; 405 unsigned i; 406 unsigned long bits; 407 408 switch (status) { 409 case -ENOENT: /* synchronous unlink */ 410 case -ECONNRESET: /* async unlink */ 411 case -ESHUTDOWN: /* hardware going away */ 412 return; 413 414 default: /* presumably an error */ 415 /* Cause a hub reset after 10 consecutive errors */ 416 dev_dbg (hub->intfdev, "transfer --> %d\n", status); 417 if ((++hub->nerrors < 10) || hub->error) 418 goto resubmit; 419 hub->error = status; 420 /* FALL THROUGH */ 421 422 /* let khubd handle things */ 423 case 0: /* we got data: port status changed */ 424 bits = 0; 425 for (i = 0; i < urb->actual_length; ++i) 426 bits |= ((unsigned long) ((*hub->buffer)[i])) 427 << (i*8); 428 hub->event_bits[0] = bits; 429 break; 430 } 431 432 hub->nerrors = 0; 433 434 /* Something happened, let khubd figure it out */ 435 kick_khubd(hub); 436 437 resubmit: 438 if (hub->quiescing) 439 return; 440 441 if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0 442 && status != -ENODEV && status != -EPERM) 443 dev_err (hub->intfdev, "resubmit --> %d\n", status); 444 } 445 446 /* USB 2.0 spec Section 11.24.2.3 */ 447 static inline int 448 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt) 449 { 450 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0), 451 HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo, 452 tt, NULL, 0, 1000); 453 } 454 455 /* 456 * enumeration blocks khubd for a long time. we use keventd instead, since 457 * long blocking there is the exception, not the rule. accordingly, HCDs 458 * talking to TTs must queue control transfers (not just bulk and iso), so 459 * both can talk to the same hub concurrently. 460 */ 461 static void hub_tt_work(struct work_struct *work) 462 { 463 struct usb_hub *hub = 464 container_of(work, struct usb_hub, tt.clear_work); 465 unsigned long flags; 466 int limit = 100; 467 468 spin_lock_irqsave (&hub->tt.lock, flags); 469 while (--limit && !list_empty (&hub->tt.clear_list)) { 470 struct list_head *next; 471 struct usb_tt_clear *clear; 472 struct usb_device *hdev = hub->hdev; 473 const struct hc_driver *drv; 474 int status; 475 476 next = hub->tt.clear_list.next; 477 clear = list_entry (next, struct usb_tt_clear, clear_list); 478 list_del (&clear->clear_list); 479 480 /* drop lock so HCD can concurrently report other TT errors */ 481 spin_unlock_irqrestore (&hub->tt.lock, flags); 482 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt); 483 if (status) 484 dev_err (&hdev->dev, 485 "clear tt %d (%04x) error %d\n", 486 clear->tt, clear->devinfo, status); 487 488 /* Tell the HCD, even if the operation failed */ 489 drv = clear->hcd->driver; 490 if (drv->clear_tt_buffer_complete) 491 (drv->clear_tt_buffer_complete)(clear->hcd, clear->ep); 492 493 kfree(clear); 494 spin_lock_irqsave(&hub->tt.lock, flags); 495 } 496 spin_unlock_irqrestore (&hub->tt.lock, flags); 497 } 498 499 /** 500 * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub 501 * @urb: an URB associated with the failed or incomplete split transaction 502 * 503 * High speed HCDs use this to tell the hub driver that some split control or 504 * bulk transaction failed in a way that requires clearing internal state of 505 * a transaction translator. This is normally detected (and reported) from 506 * interrupt context. 507 * 508 * It may not be possible for that hub to handle additional full (or low) 509 * speed transactions until that state is fully cleared out. 510 */ 511 int usb_hub_clear_tt_buffer(struct urb *urb) 512 { 513 struct usb_device *udev = urb->dev; 514 int pipe = urb->pipe; 515 struct usb_tt *tt = udev->tt; 516 unsigned long flags; 517 struct usb_tt_clear *clear; 518 519 /* we've got to cope with an arbitrary number of pending TT clears, 520 * since each TT has "at least two" buffers that can need it (and 521 * there can be many TTs per hub). even if they're uncommon. 522 */ 523 if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) { 524 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n"); 525 /* FIXME recover somehow ... RESET_TT? */ 526 return -ENOMEM; 527 } 528 529 /* info that CLEAR_TT_BUFFER needs */ 530 clear->tt = tt->multi ? udev->ttport : 1; 531 clear->devinfo = usb_pipeendpoint (pipe); 532 clear->devinfo |= udev->devnum << 4; 533 clear->devinfo |= usb_pipecontrol (pipe) 534 ? (USB_ENDPOINT_XFER_CONTROL << 11) 535 : (USB_ENDPOINT_XFER_BULK << 11); 536 if (usb_pipein (pipe)) 537 clear->devinfo |= 1 << 15; 538 539 /* info for completion callback */ 540 clear->hcd = bus_to_hcd(udev->bus); 541 clear->ep = urb->ep; 542 543 /* tell keventd to clear state for this TT */ 544 spin_lock_irqsave (&tt->lock, flags); 545 list_add_tail (&clear->clear_list, &tt->clear_list); 546 schedule_work(&tt->clear_work); 547 spin_unlock_irqrestore (&tt->lock, flags); 548 return 0; 549 } 550 EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer); 551 552 /* If do_delay is false, return the number of milliseconds the caller 553 * needs to delay. 554 */ 555 static unsigned hub_power_on(struct usb_hub *hub, bool do_delay) 556 { 557 int port1; 558 unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2; 559 unsigned delay; 560 u16 wHubCharacteristics = 561 le16_to_cpu(hub->descriptor->wHubCharacteristics); 562 563 /* Enable power on each port. Some hubs have reserved values 564 * of LPSM (> 2) in their descriptors, even though they are 565 * USB 2.0 hubs. Some hubs do not implement port-power switching 566 * but only emulate it. In all cases, the ports won't work 567 * unless we send these messages to the hub. 568 */ 569 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2) 570 dev_dbg(hub->intfdev, "enabling power on all ports\n"); 571 else 572 dev_dbg(hub->intfdev, "trying to enable port power on " 573 "non-switchable hub\n"); 574 for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++) 575 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER); 576 577 /* Wait at least 100 msec for power to become stable */ 578 delay = max(pgood_delay, (unsigned) 100); 579 if (do_delay) 580 msleep(delay); 581 return delay; 582 } 583 584 static int hub_hub_status(struct usb_hub *hub, 585 u16 *status, u16 *change) 586 { 587 int ret; 588 589 mutex_lock(&hub->status_mutex); 590 ret = get_hub_status(hub->hdev, &hub->status->hub); 591 if (ret < 0) 592 dev_err (hub->intfdev, 593 "%s failed (err = %d)\n", __func__, ret); 594 else { 595 *status = le16_to_cpu(hub->status->hub.wHubStatus); 596 *change = le16_to_cpu(hub->status->hub.wHubChange); 597 ret = 0; 598 } 599 mutex_unlock(&hub->status_mutex); 600 return ret; 601 } 602 603 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state) 604 { 605 struct usb_device *hdev = hub->hdev; 606 int ret = 0; 607 608 if (hdev->children[port1-1] && set_state) 609 usb_set_device_state(hdev->children[port1-1], 610 USB_STATE_NOTATTACHED); 611 if (!hub->error) 612 ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE); 613 if (ret) 614 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n", 615 port1, ret); 616 return ret; 617 } 618 619 /* 620 * Disable a port and mark a logical connnect-change event, so that some 621 * time later khubd will disconnect() any existing usb_device on the port 622 * and will re-enumerate if there actually is a device attached. 623 */ 624 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1) 625 { 626 dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1); 627 hub_port_disable(hub, port1, 1); 628 629 /* FIXME let caller ask to power down the port: 630 * - some devices won't enumerate without a VBUS power cycle 631 * - SRP saves power that way 632 * - ... new call, TBD ... 633 * That's easy if this hub can switch power per-port, and 634 * khubd reactivates the port later (timer, SRP, etc). 635 * Powerdown must be optional, because of reset/DFU. 636 */ 637 638 set_bit(port1, hub->change_bits); 639 kick_khubd(hub); 640 } 641 642 /** 643 * usb_remove_device - disable a device's port on its parent hub 644 * @udev: device to be disabled and removed 645 * Context: @udev locked, must be able to sleep. 646 * 647 * After @udev's port has been disabled, khubd is notified and it will 648 * see that the device has been disconnected. When the device is 649 * physically unplugged and something is plugged in, the events will 650 * be received and processed normally. 651 */ 652 int usb_remove_device(struct usb_device *udev) 653 { 654 struct usb_hub *hub; 655 struct usb_interface *intf; 656 657 if (!udev->parent) /* Can't remove a root hub */ 658 return -EINVAL; 659 hub = hdev_to_hub(udev->parent); 660 intf = to_usb_interface(hub->intfdev); 661 662 usb_autopm_get_interface(intf); 663 set_bit(udev->portnum, hub->removed_bits); 664 hub_port_logical_disconnect(hub, udev->portnum); 665 usb_autopm_put_interface(intf); 666 return 0; 667 } 668 669 enum hub_activation_type { 670 HUB_INIT, HUB_INIT2, HUB_INIT3, /* INITs must come first */ 671 HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME, 672 }; 673 674 static void hub_init_func2(struct work_struct *ws); 675 static void hub_init_func3(struct work_struct *ws); 676 677 static void hub_activate(struct usb_hub *hub, enum hub_activation_type type) 678 { 679 struct usb_device *hdev = hub->hdev; 680 int port1; 681 int status; 682 bool need_debounce_delay = false; 683 unsigned delay; 684 685 /* Continue a partial initialization */ 686 if (type == HUB_INIT2) 687 goto init2; 688 if (type == HUB_INIT3) 689 goto init3; 690 691 /* After a resume, port power should still be on. 692 * For any other type of activation, turn it on. 693 */ 694 if (type != HUB_RESUME) { 695 696 /* Speed up system boot by using a delayed_work for the 697 * hub's initial power-up delays. This is pretty awkward 698 * and the implementation looks like a home-brewed sort of 699 * setjmp/longjmp, but it saves at least 100 ms for each 700 * root hub (assuming usbcore is compiled into the kernel 701 * rather than as a module). It adds up. 702 * 703 * This can't be done for HUB_RESUME or HUB_RESET_RESUME 704 * because for those activation types the ports have to be 705 * operational when we return. In theory this could be done 706 * for HUB_POST_RESET, but it's easier not to. 707 */ 708 if (type == HUB_INIT) { 709 delay = hub_power_on(hub, false); 710 PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func2); 711 schedule_delayed_work(&hub->init_work, 712 msecs_to_jiffies(delay)); 713 714 /* Suppress autosuspend until init is done */ 715 usb_autopm_get_interface_no_resume( 716 to_usb_interface(hub->intfdev)); 717 return; /* Continues at init2: below */ 718 } else { 719 hub_power_on(hub, true); 720 } 721 } 722 init2: 723 724 /* Check each port and set hub->change_bits to let khubd know 725 * which ports need attention. 726 */ 727 for (port1 = 1; port1 <= hdev->maxchild; ++port1) { 728 struct usb_device *udev = hdev->children[port1-1]; 729 u16 portstatus, portchange; 730 731 portstatus = portchange = 0; 732 status = hub_port_status(hub, port1, &portstatus, &portchange); 733 if (udev || (portstatus & USB_PORT_STAT_CONNECTION)) 734 dev_dbg(hub->intfdev, 735 "port %d: status %04x change %04x\n", 736 port1, portstatus, portchange); 737 738 /* After anything other than HUB_RESUME (i.e., initialization 739 * or any sort of reset), every port should be disabled. 740 * Unconnected ports should likewise be disabled (paranoia), 741 * and so should ports for which we have no usb_device. 742 */ 743 if ((portstatus & USB_PORT_STAT_ENABLE) && ( 744 type != HUB_RESUME || 745 !(portstatus & USB_PORT_STAT_CONNECTION) || 746 !udev || 747 udev->state == USB_STATE_NOTATTACHED)) { 748 clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE); 749 portstatus &= ~USB_PORT_STAT_ENABLE; 750 } 751 752 /* Clear status-change flags; we'll debounce later */ 753 if (portchange & USB_PORT_STAT_C_CONNECTION) { 754 need_debounce_delay = true; 755 clear_port_feature(hub->hdev, port1, 756 USB_PORT_FEAT_C_CONNECTION); 757 } 758 if (portchange & USB_PORT_STAT_C_ENABLE) { 759 need_debounce_delay = true; 760 clear_port_feature(hub->hdev, port1, 761 USB_PORT_FEAT_C_ENABLE); 762 } 763 764 /* We can forget about a "removed" device when there's a 765 * physical disconnect or the connect status changes. 766 */ 767 if (!(portstatus & USB_PORT_STAT_CONNECTION) || 768 (portchange & USB_PORT_STAT_C_CONNECTION)) 769 clear_bit(port1, hub->removed_bits); 770 771 if (!udev || udev->state == USB_STATE_NOTATTACHED) { 772 /* Tell khubd to disconnect the device or 773 * check for a new connection 774 */ 775 if (udev || (portstatus & USB_PORT_STAT_CONNECTION)) 776 set_bit(port1, hub->change_bits); 777 778 } else if (portstatus & USB_PORT_STAT_ENABLE) { 779 /* The power session apparently survived the resume. 780 * If there was an overcurrent or suspend change 781 * (i.e., remote wakeup request), have khubd 782 * take care of it. 783 */ 784 if (portchange) 785 set_bit(port1, hub->change_bits); 786 787 } else if (udev->persist_enabled) { 788 #ifdef CONFIG_PM 789 udev->reset_resume = 1; 790 #endif 791 set_bit(port1, hub->change_bits); 792 793 } else { 794 /* The power session is gone; tell khubd */ 795 usb_set_device_state(udev, USB_STATE_NOTATTACHED); 796 set_bit(port1, hub->change_bits); 797 } 798 } 799 800 /* If no port-status-change flags were set, we don't need any 801 * debouncing. If flags were set we can try to debounce the 802 * ports all at once right now, instead of letting khubd do them 803 * one at a time later on. 804 * 805 * If any port-status changes do occur during this delay, khubd 806 * will see them later and handle them normally. 807 */ 808 if (need_debounce_delay) { 809 delay = HUB_DEBOUNCE_STABLE; 810 811 /* Don't do a long sleep inside a workqueue routine */ 812 if (type == HUB_INIT2) { 813 PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func3); 814 schedule_delayed_work(&hub->init_work, 815 msecs_to_jiffies(delay)); 816 return; /* Continues at init3: below */ 817 } else { 818 msleep(delay); 819 } 820 } 821 init3: 822 hub->quiescing = 0; 823 hub->init_done = 1; 824 825 status = usb_submit_urb(hub->urb, GFP_NOIO); 826 if (status < 0) 827 dev_err(hub->intfdev, "activate --> %d\n", status); 828 if (hub->has_indicators && blinkenlights) 829 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD); 830 831 /* Scan all ports that need attention */ 832 kick_khubd(hub); 833 834 /* Allow autosuspend if it was suppressed */ 835 if (type <= HUB_INIT3) 836 usb_autopm_put_interface_async(to_usb_interface(hub->intfdev)); 837 } 838 839 /* Implement the continuations for the delays above */ 840 static void hub_init_func2(struct work_struct *ws) 841 { 842 struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work); 843 844 hub_activate(hub, HUB_INIT2); 845 } 846 847 static void hub_init_func3(struct work_struct *ws) 848 { 849 struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work); 850 851 hub_activate(hub, HUB_INIT3); 852 } 853 854 enum hub_quiescing_type { 855 HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND 856 }; 857 858 static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type) 859 { 860 struct usb_device *hdev = hub->hdev; 861 int i; 862 863 cancel_delayed_work_sync(&hub->init_work); 864 if (!hub->init_done) { 865 hub->init_done = 1; 866 usb_autopm_put_interface_no_suspend( 867 to_usb_interface(hub->intfdev)); 868 } 869 870 /* khubd and related activity won't re-trigger */ 871 hub->quiescing = 1; 872 873 if (type != HUB_SUSPEND) { 874 /* Disconnect all the children */ 875 for (i = 0; i < hdev->maxchild; ++i) { 876 if (hdev->children[i]) 877 usb_disconnect(&hdev->children[i]); 878 } 879 } 880 881 /* Stop khubd and related activity */ 882 usb_kill_urb(hub->urb); 883 if (hub->has_indicators) 884 cancel_delayed_work_sync(&hub->leds); 885 if (hub->tt.hub) 886 cancel_work_sync(&hub->tt.clear_work); 887 } 888 889 /* caller has locked the hub device */ 890 static int hub_pre_reset(struct usb_interface *intf) 891 { 892 struct usb_hub *hub = usb_get_intfdata(intf); 893 894 hub_quiesce(hub, HUB_PRE_RESET); 895 return 0; 896 } 897 898 /* caller has locked the hub device */ 899 static int hub_post_reset(struct usb_interface *intf) 900 { 901 struct usb_hub *hub = usb_get_intfdata(intf); 902 903 hub_activate(hub, HUB_POST_RESET); 904 return 0; 905 } 906 907 static int hub_configure(struct usb_hub *hub, 908 struct usb_endpoint_descriptor *endpoint) 909 { 910 struct usb_hcd *hcd; 911 struct usb_device *hdev = hub->hdev; 912 struct device *hub_dev = hub->intfdev; 913 u16 hubstatus, hubchange; 914 u16 wHubCharacteristics; 915 unsigned int pipe; 916 int maxp, ret; 917 char *message = "out of memory"; 918 919 hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL); 920 if (!hub->buffer) { 921 ret = -ENOMEM; 922 goto fail; 923 } 924 925 hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL); 926 if (!hub->status) { 927 ret = -ENOMEM; 928 goto fail; 929 } 930 mutex_init(&hub->status_mutex); 931 932 hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL); 933 if (!hub->descriptor) { 934 ret = -ENOMEM; 935 goto fail; 936 } 937 938 /* Request the entire hub descriptor. 939 * hub->descriptor can handle USB_MAXCHILDREN ports, 940 * but the hub can/will return fewer bytes here. 941 */ 942 ret = get_hub_descriptor(hdev, hub->descriptor, 943 sizeof(*hub->descriptor)); 944 if (ret < 0) { 945 message = "can't read hub descriptor"; 946 goto fail; 947 } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) { 948 message = "hub has too many ports!"; 949 ret = -ENODEV; 950 goto fail; 951 } 952 953 hdev->maxchild = hub->descriptor->bNbrPorts; 954 dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild, 955 (hdev->maxchild == 1) ? "" : "s"); 956 957 hub->port_owners = kzalloc(hdev->maxchild * sizeof(void *), GFP_KERNEL); 958 if (!hub->port_owners) { 959 ret = -ENOMEM; 960 goto fail; 961 } 962 963 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics); 964 965 if (wHubCharacteristics & HUB_CHAR_COMPOUND) { 966 int i; 967 char portstr [USB_MAXCHILDREN + 1]; 968 969 for (i = 0; i < hdev->maxchild; i++) 970 portstr[i] = hub->descriptor->DeviceRemovable 971 [((i + 1) / 8)] & (1 << ((i + 1) % 8)) 972 ? 'F' : 'R'; 973 portstr[hdev->maxchild] = 0; 974 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr); 975 } else 976 dev_dbg(hub_dev, "standalone hub\n"); 977 978 switch (wHubCharacteristics & HUB_CHAR_LPSM) { 979 case 0x00: 980 dev_dbg(hub_dev, "ganged power switching\n"); 981 break; 982 case 0x01: 983 dev_dbg(hub_dev, "individual port power switching\n"); 984 break; 985 case 0x02: 986 case 0x03: 987 dev_dbg(hub_dev, "no power switching (usb 1.0)\n"); 988 break; 989 } 990 991 switch (wHubCharacteristics & HUB_CHAR_OCPM) { 992 case 0x00: 993 dev_dbg(hub_dev, "global over-current protection\n"); 994 break; 995 case 0x08: 996 dev_dbg(hub_dev, "individual port over-current protection\n"); 997 break; 998 case 0x10: 999 case 0x18: 1000 dev_dbg(hub_dev, "no over-current protection\n"); 1001 break; 1002 } 1003 1004 spin_lock_init (&hub->tt.lock); 1005 INIT_LIST_HEAD (&hub->tt.clear_list); 1006 INIT_WORK(&hub->tt.clear_work, hub_tt_work); 1007 switch (hdev->descriptor.bDeviceProtocol) { 1008 case 0: 1009 break; 1010 case 1: 1011 dev_dbg(hub_dev, "Single TT\n"); 1012 hub->tt.hub = hdev; 1013 break; 1014 case 2: 1015 ret = usb_set_interface(hdev, 0, 1); 1016 if (ret == 0) { 1017 dev_dbg(hub_dev, "TT per port\n"); 1018 hub->tt.multi = 1; 1019 } else 1020 dev_err(hub_dev, "Using single TT (err %d)\n", 1021 ret); 1022 hub->tt.hub = hdev; 1023 break; 1024 case 3: 1025 /* USB 3.0 hubs don't have a TT */ 1026 break; 1027 default: 1028 dev_dbg(hub_dev, "Unrecognized hub protocol %d\n", 1029 hdev->descriptor.bDeviceProtocol); 1030 break; 1031 } 1032 1033 /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */ 1034 switch (wHubCharacteristics & HUB_CHAR_TTTT) { 1035 case HUB_TTTT_8_BITS: 1036 if (hdev->descriptor.bDeviceProtocol != 0) { 1037 hub->tt.think_time = 666; 1038 dev_dbg(hub_dev, "TT requires at most %d " 1039 "FS bit times (%d ns)\n", 1040 8, hub->tt.think_time); 1041 } 1042 break; 1043 case HUB_TTTT_16_BITS: 1044 hub->tt.think_time = 666 * 2; 1045 dev_dbg(hub_dev, "TT requires at most %d " 1046 "FS bit times (%d ns)\n", 1047 16, hub->tt.think_time); 1048 break; 1049 case HUB_TTTT_24_BITS: 1050 hub->tt.think_time = 666 * 3; 1051 dev_dbg(hub_dev, "TT requires at most %d " 1052 "FS bit times (%d ns)\n", 1053 24, hub->tt.think_time); 1054 break; 1055 case HUB_TTTT_32_BITS: 1056 hub->tt.think_time = 666 * 4; 1057 dev_dbg(hub_dev, "TT requires at most %d " 1058 "FS bit times (%d ns)\n", 1059 32, hub->tt.think_time); 1060 break; 1061 } 1062 1063 /* probe() zeroes hub->indicator[] */ 1064 if (wHubCharacteristics & HUB_CHAR_PORTIND) { 1065 hub->has_indicators = 1; 1066 dev_dbg(hub_dev, "Port indicators are supported\n"); 1067 } 1068 1069 dev_dbg(hub_dev, "power on to power good time: %dms\n", 1070 hub->descriptor->bPwrOn2PwrGood * 2); 1071 1072 /* power budgeting mostly matters with bus-powered hubs, 1073 * and battery-powered root hubs (may provide just 8 mA). 1074 */ 1075 ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus); 1076 if (ret < 2) { 1077 message = "can't get hub status"; 1078 goto fail; 1079 } 1080 le16_to_cpus(&hubstatus); 1081 if (hdev == hdev->bus->root_hub) { 1082 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500) 1083 hub->mA_per_port = 500; 1084 else { 1085 hub->mA_per_port = hdev->bus_mA; 1086 hub->limited_power = 1; 1087 } 1088 } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) { 1089 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n", 1090 hub->descriptor->bHubContrCurrent); 1091 hub->limited_power = 1; 1092 if (hdev->maxchild > 0) { 1093 int remaining = hdev->bus_mA - 1094 hub->descriptor->bHubContrCurrent; 1095 1096 if (remaining < hdev->maxchild * 100) 1097 dev_warn(hub_dev, 1098 "insufficient power available " 1099 "to use all downstream ports\n"); 1100 hub->mA_per_port = 100; /* 7.2.1.1 */ 1101 } 1102 } else { /* Self-powered external hub */ 1103 /* FIXME: What about battery-powered external hubs that 1104 * provide less current per port? */ 1105 hub->mA_per_port = 500; 1106 } 1107 if (hub->mA_per_port < 500) 1108 dev_dbg(hub_dev, "%umA bus power budget for each child\n", 1109 hub->mA_per_port); 1110 1111 /* Update the HCD's internal representation of this hub before khubd 1112 * starts getting port status changes for devices under the hub. 1113 */ 1114 hcd = bus_to_hcd(hdev->bus); 1115 if (hcd->driver->update_hub_device) { 1116 ret = hcd->driver->update_hub_device(hcd, hdev, 1117 &hub->tt, GFP_KERNEL); 1118 if (ret < 0) { 1119 message = "can't update HCD hub info"; 1120 goto fail; 1121 } 1122 } 1123 1124 ret = hub_hub_status(hub, &hubstatus, &hubchange); 1125 if (ret < 0) { 1126 message = "can't get hub status"; 1127 goto fail; 1128 } 1129 1130 /* local power status reports aren't always correct */ 1131 if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER) 1132 dev_dbg(hub_dev, "local power source is %s\n", 1133 (hubstatus & HUB_STATUS_LOCAL_POWER) 1134 ? "lost (inactive)" : "good"); 1135 1136 if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0) 1137 dev_dbg(hub_dev, "%sover-current condition exists\n", 1138 (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no "); 1139 1140 /* set up the interrupt endpoint 1141 * We use the EP's maxpacket size instead of (PORTS+1+7)/8 1142 * bytes as USB2.0[11.12.3] says because some hubs are known 1143 * to send more data (and thus cause overflow). For root hubs, 1144 * maxpktsize is defined in hcd.c's fake endpoint descriptors 1145 * to be big enough for at least USB_MAXCHILDREN ports. */ 1146 pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress); 1147 maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe)); 1148 1149 if (maxp > sizeof(*hub->buffer)) 1150 maxp = sizeof(*hub->buffer); 1151 1152 hub->urb = usb_alloc_urb(0, GFP_KERNEL); 1153 if (!hub->urb) { 1154 ret = -ENOMEM; 1155 goto fail; 1156 } 1157 1158 usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq, 1159 hub, endpoint->bInterval); 1160 1161 /* maybe cycle the hub leds */ 1162 if (hub->has_indicators && blinkenlights) 1163 hub->indicator [0] = INDICATOR_CYCLE; 1164 1165 hub_activate(hub, HUB_INIT); 1166 return 0; 1167 1168 fail: 1169 dev_err (hub_dev, "config failed, %s (err %d)\n", 1170 message, ret); 1171 /* hub_disconnect() frees urb and descriptor */ 1172 return ret; 1173 } 1174 1175 static void hub_release(struct kref *kref) 1176 { 1177 struct usb_hub *hub = container_of(kref, struct usb_hub, kref); 1178 1179 usb_put_intf(to_usb_interface(hub->intfdev)); 1180 kfree(hub); 1181 } 1182 1183 static unsigned highspeed_hubs; 1184 1185 static void hub_disconnect(struct usb_interface *intf) 1186 { 1187 struct usb_hub *hub = usb_get_intfdata (intf); 1188 1189 /* Take the hub off the event list and don't let it be added again */ 1190 spin_lock_irq(&hub_event_lock); 1191 if (!list_empty(&hub->event_list)) { 1192 list_del_init(&hub->event_list); 1193 usb_autopm_put_interface_no_suspend(intf); 1194 } 1195 hub->disconnected = 1; 1196 spin_unlock_irq(&hub_event_lock); 1197 1198 /* Disconnect all children and quiesce the hub */ 1199 hub->error = 0; 1200 hub_quiesce(hub, HUB_DISCONNECT); 1201 1202 usb_set_intfdata (intf, NULL); 1203 hub->hdev->maxchild = 0; 1204 1205 if (hub->hdev->speed == USB_SPEED_HIGH) 1206 highspeed_hubs--; 1207 1208 usb_free_urb(hub->urb); 1209 kfree(hub->port_owners); 1210 kfree(hub->descriptor); 1211 kfree(hub->status); 1212 kfree(hub->buffer); 1213 1214 kref_put(&hub->kref, hub_release); 1215 } 1216 1217 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id) 1218 { 1219 struct usb_host_interface *desc; 1220 struct usb_endpoint_descriptor *endpoint; 1221 struct usb_device *hdev; 1222 struct usb_hub *hub; 1223 1224 desc = intf->cur_altsetting; 1225 hdev = interface_to_usbdev(intf); 1226 1227 if (hdev->level == MAX_TOPO_LEVEL) { 1228 dev_err(&intf->dev, 1229 "Unsupported bus topology: hub nested too deep\n"); 1230 return -E2BIG; 1231 } 1232 1233 #ifdef CONFIG_USB_OTG_BLACKLIST_HUB 1234 if (hdev->parent) { 1235 dev_warn(&intf->dev, "ignoring external hub\n"); 1236 return -ENODEV; 1237 } 1238 #endif 1239 1240 /* Some hubs have a subclass of 1, which AFAICT according to the */ 1241 /* specs is not defined, but it works */ 1242 if ((desc->desc.bInterfaceSubClass != 0) && 1243 (desc->desc.bInterfaceSubClass != 1)) { 1244 descriptor_error: 1245 dev_err (&intf->dev, "bad descriptor, ignoring hub\n"); 1246 return -EIO; 1247 } 1248 1249 /* Multiple endpoints? What kind of mutant ninja-hub is this? */ 1250 if (desc->desc.bNumEndpoints != 1) 1251 goto descriptor_error; 1252 1253 endpoint = &desc->endpoint[0].desc; 1254 1255 /* If it's not an interrupt in endpoint, we'd better punt! */ 1256 if (!usb_endpoint_is_int_in(endpoint)) 1257 goto descriptor_error; 1258 1259 /* We found a hub */ 1260 dev_info (&intf->dev, "USB hub found\n"); 1261 1262 hub = kzalloc(sizeof(*hub), GFP_KERNEL); 1263 if (!hub) { 1264 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n"); 1265 return -ENOMEM; 1266 } 1267 1268 kref_init(&hub->kref); 1269 INIT_LIST_HEAD(&hub->event_list); 1270 hub->intfdev = &intf->dev; 1271 hub->hdev = hdev; 1272 INIT_DELAYED_WORK(&hub->leds, led_work); 1273 INIT_DELAYED_WORK(&hub->init_work, NULL); 1274 usb_get_intf(intf); 1275 1276 usb_set_intfdata (intf, hub); 1277 intf->needs_remote_wakeup = 1; 1278 1279 if (hdev->speed == USB_SPEED_HIGH) 1280 highspeed_hubs++; 1281 1282 if (hub_configure(hub, endpoint) >= 0) 1283 return 0; 1284 1285 hub_disconnect (intf); 1286 return -ENODEV; 1287 } 1288 1289 static int 1290 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data) 1291 { 1292 struct usb_device *hdev = interface_to_usbdev (intf); 1293 1294 /* assert ifno == 0 (part of hub spec) */ 1295 switch (code) { 1296 case USBDEVFS_HUB_PORTINFO: { 1297 struct usbdevfs_hub_portinfo *info = user_data; 1298 int i; 1299 1300 spin_lock_irq(&device_state_lock); 1301 if (hdev->devnum <= 0) 1302 info->nports = 0; 1303 else { 1304 info->nports = hdev->maxchild; 1305 for (i = 0; i < info->nports; i++) { 1306 if (hdev->children[i] == NULL) 1307 info->port[i] = 0; 1308 else 1309 info->port[i] = 1310 hdev->children[i]->devnum; 1311 } 1312 } 1313 spin_unlock_irq(&device_state_lock); 1314 1315 return info->nports + 1; 1316 } 1317 1318 default: 1319 return -ENOSYS; 1320 } 1321 } 1322 1323 /* 1324 * Allow user programs to claim ports on a hub. When a device is attached 1325 * to one of these "claimed" ports, the program will "own" the device. 1326 */ 1327 static int find_port_owner(struct usb_device *hdev, unsigned port1, 1328 void ***ppowner) 1329 { 1330 if (hdev->state == USB_STATE_NOTATTACHED) 1331 return -ENODEV; 1332 if (port1 == 0 || port1 > hdev->maxchild) 1333 return -EINVAL; 1334 1335 /* This assumes that devices not managed by the hub driver 1336 * will always have maxchild equal to 0. 1337 */ 1338 *ppowner = &(hdev_to_hub(hdev)->port_owners[port1 - 1]); 1339 return 0; 1340 } 1341 1342 /* In the following three functions, the caller must hold hdev's lock */ 1343 int usb_hub_claim_port(struct usb_device *hdev, unsigned port1, void *owner) 1344 { 1345 int rc; 1346 void **powner; 1347 1348 rc = find_port_owner(hdev, port1, &powner); 1349 if (rc) 1350 return rc; 1351 if (*powner) 1352 return -EBUSY; 1353 *powner = owner; 1354 return rc; 1355 } 1356 1357 int usb_hub_release_port(struct usb_device *hdev, unsigned port1, void *owner) 1358 { 1359 int rc; 1360 void **powner; 1361 1362 rc = find_port_owner(hdev, port1, &powner); 1363 if (rc) 1364 return rc; 1365 if (*powner != owner) 1366 return -ENOENT; 1367 *powner = NULL; 1368 return rc; 1369 } 1370 1371 void usb_hub_release_all_ports(struct usb_device *hdev, void *owner) 1372 { 1373 int n; 1374 void **powner; 1375 1376 n = find_port_owner(hdev, 1, &powner); 1377 if (n == 0) { 1378 for (; n < hdev->maxchild; (++n, ++powner)) { 1379 if (*powner == owner) 1380 *powner = NULL; 1381 } 1382 } 1383 } 1384 1385 /* The caller must hold udev's lock */ 1386 bool usb_device_is_owned(struct usb_device *udev) 1387 { 1388 struct usb_hub *hub; 1389 1390 if (udev->state == USB_STATE_NOTATTACHED || !udev->parent) 1391 return false; 1392 hub = hdev_to_hub(udev->parent); 1393 return !!hub->port_owners[udev->portnum - 1]; 1394 } 1395 1396 1397 static void recursively_mark_NOTATTACHED(struct usb_device *udev) 1398 { 1399 int i; 1400 1401 for (i = 0; i < udev->maxchild; ++i) { 1402 if (udev->children[i]) 1403 recursively_mark_NOTATTACHED(udev->children[i]); 1404 } 1405 if (udev->state == USB_STATE_SUSPENDED) { 1406 udev->discon_suspended = 1; 1407 udev->active_duration -= jiffies; 1408 } 1409 udev->state = USB_STATE_NOTATTACHED; 1410 } 1411 1412 /** 1413 * usb_set_device_state - change a device's current state (usbcore, hcds) 1414 * @udev: pointer to device whose state should be changed 1415 * @new_state: new state value to be stored 1416 * 1417 * udev->state is _not_ fully protected by the device lock. Although 1418 * most transitions are made only while holding the lock, the state can 1419 * can change to USB_STATE_NOTATTACHED at almost any time. This 1420 * is so that devices can be marked as disconnected as soon as possible, 1421 * without having to wait for any semaphores to be released. As a result, 1422 * all changes to any device's state must be protected by the 1423 * device_state_lock spinlock. 1424 * 1425 * Once a device has been added to the device tree, all changes to its state 1426 * should be made using this routine. The state should _not_ be set directly. 1427 * 1428 * If udev->state is already USB_STATE_NOTATTACHED then no change is made. 1429 * Otherwise udev->state is set to new_state, and if new_state is 1430 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set 1431 * to USB_STATE_NOTATTACHED. 1432 */ 1433 void usb_set_device_state(struct usb_device *udev, 1434 enum usb_device_state new_state) 1435 { 1436 unsigned long flags; 1437 1438 spin_lock_irqsave(&device_state_lock, flags); 1439 if (udev->state == USB_STATE_NOTATTACHED) 1440 ; /* do nothing */ 1441 else if (new_state != USB_STATE_NOTATTACHED) { 1442 1443 /* root hub wakeup capabilities are managed out-of-band 1444 * and may involve silicon errata ... ignore them here. 1445 */ 1446 if (udev->parent) { 1447 if (udev->state == USB_STATE_SUSPENDED 1448 || new_state == USB_STATE_SUSPENDED) 1449 ; /* No change to wakeup settings */ 1450 else if (new_state == USB_STATE_CONFIGURED) 1451 device_init_wakeup(&udev->dev, 1452 (udev->actconfig->desc.bmAttributes 1453 & USB_CONFIG_ATT_WAKEUP)); 1454 else 1455 device_init_wakeup(&udev->dev, 0); 1456 } 1457 if (udev->state == USB_STATE_SUSPENDED && 1458 new_state != USB_STATE_SUSPENDED) 1459 udev->active_duration -= jiffies; 1460 else if (new_state == USB_STATE_SUSPENDED && 1461 udev->state != USB_STATE_SUSPENDED) 1462 udev->active_duration += jiffies; 1463 udev->state = new_state; 1464 } else 1465 recursively_mark_NOTATTACHED(udev); 1466 spin_unlock_irqrestore(&device_state_lock, flags); 1467 } 1468 EXPORT_SYMBOL_GPL(usb_set_device_state); 1469 1470 /* 1471 * WUSB devices are simple: they have no hubs behind, so the mapping 1472 * device <-> virtual port number becomes 1:1. Why? to simplify the 1473 * life of the device connection logic in 1474 * drivers/usb/wusbcore/devconnect.c. When we do the initial secret 1475 * handshake we need to assign a temporary address in the unauthorized 1476 * space. For simplicity we use the first virtual port number found to 1477 * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()] 1478 * and that becomes it's address [X < 128] or its unauthorized address 1479 * [X | 0x80]. 1480 * 1481 * We add 1 as an offset to the one-based USB-stack port number 1482 * (zero-based wusb virtual port index) for two reasons: (a) dev addr 1483 * 0 is reserved by USB for default address; (b) Linux's USB stack 1484 * uses always #1 for the root hub of the controller. So USB stack's 1485 * port #1, which is wusb virtual-port #0 has address #2. 1486 * 1487 * Devices connected under xHCI are not as simple. The host controller 1488 * supports virtualization, so the hardware assigns device addresses and 1489 * the HCD must setup data structures before issuing a set address 1490 * command to the hardware. 1491 */ 1492 static void choose_address(struct usb_device *udev) 1493 { 1494 int devnum; 1495 struct usb_bus *bus = udev->bus; 1496 1497 /* If khubd ever becomes multithreaded, this will need a lock */ 1498 if (udev->wusb) { 1499 devnum = udev->portnum + 1; 1500 BUG_ON(test_bit(devnum, bus->devmap.devicemap)); 1501 } else { 1502 /* Try to allocate the next devnum beginning at 1503 * bus->devnum_next. */ 1504 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1505 bus->devnum_next); 1506 if (devnum >= 128) 1507 devnum = find_next_zero_bit(bus->devmap.devicemap, 1508 128, 1); 1509 bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1); 1510 } 1511 if (devnum < 128) { 1512 set_bit(devnum, bus->devmap.devicemap); 1513 udev->devnum = devnum; 1514 } 1515 } 1516 1517 static void release_address(struct usb_device *udev) 1518 { 1519 if (udev->devnum > 0) { 1520 clear_bit(udev->devnum, udev->bus->devmap.devicemap); 1521 udev->devnum = -1; 1522 } 1523 } 1524 1525 static void update_address(struct usb_device *udev, int devnum) 1526 { 1527 /* The address for a WUSB device is managed by wusbcore. */ 1528 if (!udev->wusb) 1529 udev->devnum = devnum; 1530 } 1531 1532 #ifdef CONFIG_USB_SUSPEND 1533 1534 static void usb_stop_pm(struct usb_device *udev) 1535 { 1536 /* Synchronize with the ksuspend thread to prevent any more 1537 * autosuspend requests from being submitted, and decrement 1538 * the parent's count of unsuspended children. 1539 */ 1540 usb_pm_lock(udev); 1541 if (udev->parent && !udev->discon_suspended) 1542 usb_autosuspend_device(udev->parent); 1543 usb_pm_unlock(udev); 1544 1545 /* Stop any autosuspend or autoresume requests already submitted */ 1546 cancel_delayed_work_sync(&udev->autosuspend); 1547 cancel_work_sync(&udev->autoresume); 1548 } 1549 1550 #else 1551 1552 static inline void usb_stop_pm(struct usb_device *udev) 1553 { } 1554 1555 #endif 1556 1557 /** 1558 * usb_disconnect - disconnect a device (usbcore-internal) 1559 * @pdev: pointer to device being disconnected 1560 * Context: !in_interrupt () 1561 * 1562 * Something got disconnected. Get rid of it and all of its children. 1563 * 1564 * If *pdev is a normal device then the parent hub must already be locked. 1565 * If *pdev is a root hub then this routine will acquire the 1566 * usb_bus_list_lock on behalf of the caller. 1567 * 1568 * Only hub drivers (including virtual root hub drivers for host 1569 * controllers) should ever call this. 1570 * 1571 * This call is synchronous, and may not be used in an interrupt context. 1572 */ 1573 void usb_disconnect(struct usb_device **pdev) 1574 { 1575 struct usb_device *udev = *pdev; 1576 int i; 1577 1578 if (!udev) { 1579 pr_debug ("%s nodev\n", __func__); 1580 return; 1581 } 1582 1583 /* mark the device as inactive, so any further urb submissions for 1584 * this device (and any of its children) will fail immediately. 1585 * this quiesces everyting except pending urbs. 1586 */ 1587 usb_set_device_state(udev, USB_STATE_NOTATTACHED); 1588 dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum); 1589 1590 usb_lock_device(udev); 1591 1592 /* Free up all the children before we remove this device */ 1593 for (i = 0; i < USB_MAXCHILDREN; i++) { 1594 if (udev->children[i]) 1595 usb_disconnect(&udev->children[i]); 1596 } 1597 1598 /* deallocate hcd/hardware state ... nuking all pending urbs and 1599 * cleaning up all state associated with the current configuration 1600 * so that the hardware is now fully quiesced. 1601 */ 1602 dev_dbg (&udev->dev, "unregistering device\n"); 1603 usb_disable_device(udev, 0); 1604 usb_hcd_synchronize_unlinks(udev); 1605 1606 usb_remove_ep_devs(&udev->ep0); 1607 usb_unlock_device(udev); 1608 1609 /* Unregister the device. The device driver is responsible 1610 * for de-configuring the device and invoking the remove-device 1611 * notifier chain (used by usbfs and possibly others). 1612 */ 1613 device_del(&udev->dev); 1614 1615 /* Free the device number and delete the parent's children[] 1616 * (or root_hub) pointer. 1617 */ 1618 release_address(udev); 1619 1620 /* Avoid races with recursively_mark_NOTATTACHED() */ 1621 spin_lock_irq(&device_state_lock); 1622 *pdev = NULL; 1623 spin_unlock_irq(&device_state_lock); 1624 1625 usb_stop_pm(udev); 1626 1627 put_device(&udev->dev); 1628 } 1629 1630 #ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES 1631 static void show_string(struct usb_device *udev, char *id, char *string) 1632 { 1633 if (!string) 1634 return; 1635 dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string); 1636 } 1637 1638 static void announce_device(struct usb_device *udev) 1639 { 1640 dev_info(&udev->dev, "New USB device found, idVendor=%04x, idProduct=%04x\n", 1641 le16_to_cpu(udev->descriptor.idVendor), 1642 le16_to_cpu(udev->descriptor.idProduct)); 1643 dev_info(&udev->dev, 1644 "New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n", 1645 udev->descriptor.iManufacturer, 1646 udev->descriptor.iProduct, 1647 udev->descriptor.iSerialNumber); 1648 show_string(udev, "Product", udev->product); 1649 show_string(udev, "Manufacturer", udev->manufacturer); 1650 show_string(udev, "SerialNumber", udev->serial); 1651 } 1652 #else 1653 static inline void announce_device(struct usb_device *udev) { } 1654 #endif 1655 1656 #ifdef CONFIG_USB_OTG 1657 #include "otg_whitelist.h" 1658 #endif 1659 1660 /** 1661 * usb_enumerate_device_otg - FIXME (usbcore-internal) 1662 * @udev: newly addressed device (in ADDRESS state) 1663 * 1664 * Finish enumeration for On-The-Go devices 1665 */ 1666 static int usb_enumerate_device_otg(struct usb_device *udev) 1667 { 1668 int err = 0; 1669 1670 #ifdef CONFIG_USB_OTG 1671 /* 1672 * OTG-aware devices on OTG-capable root hubs may be able to use SRP, 1673 * to wake us after we've powered off VBUS; and HNP, switching roles 1674 * "host" to "peripheral". The OTG descriptor helps figure this out. 1675 */ 1676 if (!udev->bus->is_b_host 1677 && udev->config 1678 && udev->parent == udev->bus->root_hub) { 1679 struct usb_otg_descriptor *desc = NULL; 1680 struct usb_bus *bus = udev->bus; 1681 1682 /* descriptor may appear anywhere in config */ 1683 if (__usb_get_extra_descriptor (udev->rawdescriptors[0], 1684 le16_to_cpu(udev->config[0].desc.wTotalLength), 1685 USB_DT_OTG, (void **) &desc) == 0) { 1686 if (desc->bmAttributes & USB_OTG_HNP) { 1687 unsigned port1 = udev->portnum; 1688 1689 dev_info(&udev->dev, 1690 "Dual-Role OTG device on %sHNP port\n", 1691 (port1 == bus->otg_port) 1692 ? "" : "non-"); 1693 1694 /* enable HNP before suspend, it's simpler */ 1695 if (port1 == bus->otg_port) 1696 bus->b_hnp_enable = 1; 1697 err = usb_control_msg(udev, 1698 usb_sndctrlpipe(udev, 0), 1699 USB_REQ_SET_FEATURE, 0, 1700 bus->b_hnp_enable 1701 ? USB_DEVICE_B_HNP_ENABLE 1702 : USB_DEVICE_A_ALT_HNP_SUPPORT, 1703 0, NULL, 0, USB_CTRL_SET_TIMEOUT); 1704 if (err < 0) { 1705 /* OTG MESSAGE: report errors here, 1706 * customize to match your product. 1707 */ 1708 dev_info(&udev->dev, 1709 "can't set HNP mode: %d\n", 1710 err); 1711 bus->b_hnp_enable = 0; 1712 } 1713 } 1714 } 1715 } 1716 1717 if (!is_targeted(udev)) { 1718 1719 /* Maybe it can talk to us, though we can't talk to it. 1720 * (Includes HNP test device.) 1721 */ 1722 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) { 1723 err = usb_port_suspend(udev, PMSG_SUSPEND); 1724 if (err < 0) 1725 dev_dbg(&udev->dev, "HNP fail, %d\n", err); 1726 } 1727 err = -ENOTSUPP; 1728 goto fail; 1729 } 1730 fail: 1731 #endif 1732 return err; 1733 } 1734 1735 1736 /** 1737 * usb_enumerate_device - Read device configs/intfs/otg (usbcore-internal) 1738 * @udev: newly addressed device (in ADDRESS state) 1739 * 1740 * This is only called by usb_new_device() and usb_authorize_device() 1741 * and FIXME -- all comments that apply to them apply here wrt to 1742 * environment. 1743 * 1744 * If the device is WUSB and not authorized, we don't attempt to read 1745 * the string descriptors, as they will be errored out by the device 1746 * until it has been authorized. 1747 */ 1748 static int usb_enumerate_device(struct usb_device *udev) 1749 { 1750 int err; 1751 1752 if (udev->config == NULL) { 1753 err = usb_get_configuration(udev); 1754 if (err < 0) { 1755 dev_err(&udev->dev, "can't read configurations, error %d\n", 1756 err); 1757 goto fail; 1758 } 1759 } 1760 if (udev->wusb == 1 && udev->authorized == 0) { 1761 udev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL); 1762 udev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL); 1763 udev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL); 1764 } 1765 else { 1766 /* read the standard strings and cache them if present */ 1767 udev->product = usb_cache_string(udev, udev->descriptor.iProduct); 1768 udev->manufacturer = usb_cache_string(udev, 1769 udev->descriptor.iManufacturer); 1770 udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber); 1771 } 1772 err = usb_enumerate_device_otg(udev); 1773 fail: 1774 return err; 1775 } 1776 1777 1778 /** 1779 * usb_new_device - perform initial device setup (usbcore-internal) 1780 * @udev: newly addressed device (in ADDRESS state) 1781 * 1782 * This is called with devices which have been detected but not fully 1783 * enumerated. The device descriptor is available, but not descriptors 1784 * for any device configuration. The caller must have locked either 1785 * the parent hub (if udev is a normal device) or else the 1786 * usb_bus_list_lock (if udev is a root hub). The parent's pointer to 1787 * udev has already been installed, but udev is not yet visible through 1788 * sysfs or other filesystem code. 1789 * 1790 * It will return if the device is configured properly or not. Zero if 1791 * the interface was registered with the driver core; else a negative 1792 * errno value. 1793 * 1794 * This call is synchronous, and may not be used in an interrupt context. 1795 * 1796 * Only the hub driver or root-hub registrar should ever call this. 1797 */ 1798 int usb_new_device(struct usb_device *udev) 1799 { 1800 int err; 1801 1802 /* Increment the parent's count of unsuspended children */ 1803 if (udev->parent) 1804 usb_autoresume_device(udev->parent); 1805 1806 usb_detect_quirks(udev); 1807 err = usb_enumerate_device(udev); /* Read descriptors */ 1808 if (err < 0) 1809 goto fail; 1810 dev_dbg(&udev->dev, "udev %d, busnum %d, minor = %d\n", 1811 udev->devnum, udev->bus->busnum, 1812 (((udev->bus->busnum-1) * 128) + (udev->devnum-1))); 1813 /* export the usbdev device-node for libusb */ 1814 udev->dev.devt = MKDEV(USB_DEVICE_MAJOR, 1815 (((udev->bus->busnum-1) * 128) + (udev->devnum-1))); 1816 1817 /* Tell the world! */ 1818 announce_device(udev); 1819 1820 /* Register the device. The device driver is responsible 1821 * for configuring the device and invoking the add-device 1822 * notifier chain (used by usbfs and possibly others). 1823 */ 1824 err = device_add(&udev->dev); 1825 if (err) { 1826 dev_err(&udev->dev, "can't device_add, error %d\n", err); 1827 goto fail; 1828 } 1829 1830 (void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev); 1831 return err; 1832 1833 fail: 1834 usb_set_device_state(udev, USB_STATE_NOTATTACHED); 1835 usb_stop_pm(udev); 1836 return err; 1837 } 1838 1839 1840 /** 1841 * usb_deauthorize_device - deauthorize a device (usbcore-internal) 1842 * @usb_dev: USB device 1843 * 1844 * Move the USB device to a very basic state where interfaces are disabled 1845 * and the device is in fact unconfigured and unusable. 1846 * 1847 * We share a lock (that we have) with device_del(), so we need to 1848 * defer its call. 1849 */ 1850 int usb_deauthorize_device(struct usb_device *usb_dev) 1851 { 1852 usb_lock_device(usb_dev); 1853 if (usb_dev->authorized == 0) 1854 goto out_unauthorized; 1855 1856 usb_dev->authorized = 0; 1857 usb_set_configuration(usb_dev, -1); 1858 1859 kfree(usb_dev->product); 1860 usb_dev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL); 1861 kfree(usb_dev->manufacturer); 1862 usb_dev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL); 1863 kfree(usb_dev->serial); 1864 usb_dev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL); 1865 1866 usb_destroy_configuration(usb_dev); 1867 usb_dev->descriptor.bNumConfigurations = 0; 1868 1869 out_unauthorized: 1870 usb_unlock_device(usb_dev); 1871 return 0; 1872 } 1873 1874 1875 int usb_authorize_device(struct usb_device *usb_dev) 1876 { 1877 int result = 0, c; 1878 1879 usb_lock_device(usb_dev); 1880 if (usb_dev->authorized == 1) 1881 goto out_authorized; 1882 1883 result = usb_autoresume_device(usb_dev); 1884 if (result < 0) { 1885 dev_err(&usb_dev->dev, 1886 "can't autoresume for authorization: %d\n", result); 1887 goto error_autoresume; 1888 } 1889 result = usb_get_device_descriptor(usb_dev, sizeof(usb_dev->descriptor)); 1890 if (result < 0) { 1891 dev_err(&usb_dev->dev, "can't re-read device descriptor for " 1892 "authorization: %d\n", result); 1893 goto error_device_descriptor; 1894 } 1895 1896 kfree(usb_dev->product); 1897 usb_dev->product = NULL; 1898 kfree(usb_dev->manufacturer); 1899 usb_dev->manufacturer = NULL; 1900 kfree(usb_dev->serial); 1901 usb_dev->serial = NULL; 1902 1903 usb_dev->authorized = 1; 1904 result = usb_enumerate_device(usb_dev); 1905 if (result < 0) 1906 goto error_enumerate; 1907 /* Choose and set the configuration. This registers the interfaces 1908 * with the driver core and lets interface drivers bind to them. 1909 */ 1910 c = usb_choose_configuration(usb_dev); 1911 if (c >= 0) { 1912 result = usb_set_configuration(usb_dev, c); 1913 if (result) { 1914 dev_err(&usb_dev->dev, 1915 "can't set config #%d, error %d\n", c, result); 1916 /* This need not be fatal. The user can try to 1917 * set other configurations. */ 1918 } 1919 } 1920 dev_info(&usb_dev->dev, "authorized to connect\n"); 1921 1922 error_enumerate: 1923 error_device_descriptor: 1924 usb_autosuspend_device(usb_dev); 1925 error_autoresume: 1926 out_authorized: 1927 usb_unlock_device(usb_dev); // complements locktree 1928 return result; 1929 } 1930 1931 1932 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */ 1933 static unsigned hub_is_wusb(struct usb_hub *hub) 1934 { 1935 struct usb_hcd *hcd; 1936 if (hub->hdev->parent != NULL) /* not a root hub? */ 1937 return 0; 1938 hcd = container_of(hub->hdev->bus, struct usb_hcd, self); 1939 return hcd->wireless; 1940 } 1941 1942 1943 #define PORT_RESET_TRIES 5 1944 #define SET_ADDRESS_TRIES 2 1945 #define GET_DESCRIPTOR_TRIES 2 1946 #define SET_CONFIG_TRIES (2 * (use_both_schemes + 1)) 1947 #define USE_NEW_SCHEME(i) ((i) / 2 == old_scheme_first) 1948 1949 #define HUB_ROOT_RESET_TIME 50 /* times are in msec */ 1950 #define HUB_SHORT_RESET_TIME 10 1951 #define HUB_LONG_RESET_TIME 200 1952 #define HUB_RESET_TIMEOUT 500 1953 1954 static int hub_port_wait_reset(struct usb_hub *hub, int port1, 1955 struct usb_device *udev, unsigned int delay) 1956 { 1957 int delay_time, ret; 1958 u16 portstatus; 1959 u16 portchange; 1960 1961 for (delay_time = 0; 1962 delay_time < HUB_RESET_TIMEOUT; 1963 delay_time += delay) { 1964 /* wait to give the device a chance to reset */ 1965 msleep(delay); 1966 1967 /* read and decode port status */ 1968 ret = hub_port_status(hub, port1, &portstatus, &portchange); 1969 if (ret < 0) 1970 return ret; 1971 1972 /* Device went away? */ 1973 if (!(portstatus & USB_PORT_STAT_CONNECTION)) 1974 return -ENOTCONN; 1975 1976 /* bomb out completely if the connection bounced */ 1977 if ((portchange & USB_PORT_STAT_C_CONNECTION)) 1978 return -ENOTCONN; 1979 1980 /* if we`ve finished resetting, then break out of the loop */ 1981 if (!(portstatus & USB_PORT_STAT_RESET) && 1982 (portstatus & USB_PORT_STAT_ENABLE)) { 1983 if (hub_is_wusb(hub)) 1984 udev->speed = USB_SPEED_VARIABLE; 1985 else if (portstatus & USB_PORT_STAT_HIGH_SPEED) 1986 udev->speed = USB_SPEED_HIGH; 1987 else if (portstatus & USB_PORT_STAT_LOW_SPEED) 1988 udev->speed = USB_SPEED_LOW; 1989 else 1990 udev->speed = USB_SPEED_FULL; 1991 return 0; 1992 } 1993 1994 /* switch to the long delay after two short delay failures */ 1995 if (delay_time >= 2 * HUB_SHORT_RESET_TIME) 1996 delay = HUB_LONG_RESET_TIME; 1997 1998 dev_dbg (hub->intfdev, 1999 "port %d not reset yet, waiting %dms\n", 2000 port1, delay); 2001 } 2002 2003 return -EBUSY; 2004 } 2005 2006 static int hub_port_reset(struct usb_hub *hub, int port1, 2007 struct usb_device *udev, unsigned int delay) 2008 { 2009 int i, status; 2010 2011 /* Block EHCI CF initialization during the port reset. 2012 * Some companion controllers don't like it when they mix. 2013 */ 2014 down_read(&ehci_cf_port_reset_rwsem); 2015 2016 /* Reset the port */ 2017 for (i = 0; i < PORT_RESET_TRIES; i++) { 2018 status = set_port_feature(hub->hdev, 2019 port1, USB_PORT_FEAT_RESET); 2020 if (status) 2021 dev_err(hub->intfdev, 2022 "cannot reset port %d (err = %d)\n", 2023 port1, status); 2024 else { 2025 status = hub_port_wait_reset(hub, port1, udev, delay); 2026 if (status && status != -ENOTCONN) 2027 dev_dbg(hub->intfdev, 2028 "port_wait_reset: err = %d\n", 2029 status); 2030 } 2031 2032 /* return on disconnect or reset */ 2033 switch (status) { 2034 case 0: 2035 /* TRSTRCY = 10 ms; plus some extra */ 2036 msleep(10 + 40); 2037 update_address(udev, 0); 2038 /* FALL THROUGH */ 2039 case -ENOTCONN: 2040 case -ENODEV: 2041 clear_port_feature(hub->hdev, 2042 port1, USB_PORT_FEAT_C_RESET); 2043 /* FIXME need disconnect() for NOTATTACHED device */ 2044 usb_set_device_state(udev, status 2045 ? USB_STATE_NOTATTACHED 2046 : USB_STATE_DEFAULT); 2047 goto done; 2048 } 2049 2050 dev_dbg (hub->intfdev, 2051 "port %d not enabled, trying reset again...\n", 2052 port1); 2053 delay = HUB_LONG_RESET_TIME; 2054 } 2055 2056 dev_err (hub->intfdev, 2057 "Cannot enable port %i. Maybe the USB cable is bad?\n", 2058 port1); 2059 2060 done: 2061 up_read(&ehci_cf_port_reset_rwsem); 2062 return status; 2063 } 2064 2065 #ifdef CONFIG_PM 2066 2067 #define MASK_BITS (USB_PORT_STAT_POWER | USB_PORT_STAT_CONNECTION | \ 2068 USB_PORT_STAT_SUSPEND) 2069 #define WANT_BITS (USB_PORT_STAT_POWER | USB_PORT_STAT_CONNECTION) 2070 2071 /* Determine whether the device on a port is ready for a normal resume, 2072 * is ready for a reset-resume, or should be disconnected. 2073 */ 2074 static int check_port_resume_type(struct usb_device *udev, 2075 struct usb_hub *hub, int port1, 2076 int status, unsigned portchange, unsigned portstatus) 2077 { 2078 /* Is the device still present? */ 2079 if (status || (portstatus & MASK_BITS) != WANT_BITS) { 2080 if (status >= 0) 2081 status = -ENODEV; 2082 } 2083 2084 /* Can't do a normal resume if the port isn't enabled, 2085 * so try a reset-resume instead. 2086 */ 2087 else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) { 2088 if (udev->persist_enabled) 2089 udev->reset_resume = 1; 2090 else 2091 status = -ENODEV; 2092 } 2093 2094 if (status) { 2095 dev_dbg(hub->intfdev, 2096 "port %d status %04x.%04x after resume, %d\n", 2097 port1, portchange, portstatus, status); 2098 } else if (udev->reset_resume) { 2099 2100 /* Late port handoff can set status-change bits */ 2101 if (portchange & USB_PORT_STAT_C_CONNECTION) 2102 clear_port_feature(hub->hdev, port1, 2103 USB_PORT_FEAT_C_CONNECTION); 2104 if (portchange & USB_PORT_STAT_C_ENABLE) 2105 clear_port_feature(hub->hdev, port1, 2106 USB_PORT_FEAT_C_ENABLE); 2107 } 2108 2109 return status; 2110 } 2111 2112 #ifdef CONFIG_USB_SUSPEND 2113 2114 /* 2115 * usb_port_suspend - suspend a usb device's upstream port 2116 * @udev: device that's no longer in active use, not a root hub 2117 * Context: must be able to sleep; device not locked; pm locks held 2118 * 2119 * Suspends a USB device that isn't in active use, conserving power. 2120 * Devices may wake out of a suspend, if anything important happens, 2121 * using the remote wakeup mechanism. They may also be taken out of 2122 * suspend by the host, using usb_port_resume(). It's also routine 2123 * to disconnect devices while they are suspended. 2124 * 2125 * This only affects the USB hardware for a device; its interfaces 2126 * (and, for hubs, child devices) must already have been suspended. 2127 * 2128 * Selective port suspend reduces power; most suspended devices draw 2129 * less than 500 uA. It's also used in OTG, along with remote wakeup. 2130 * All devices below the suspended port are also suspended. 2131 * 2132 * Devices leave suspend state when the host wakes them up. Some devices 2133 * also support "remote wakeup", where the device can activate the USB 2134 * tree above them to deliver data, such as a keypress or packet. In 2135 * some cases, this wakes the USB host. 2136 * 2137 * Suspending OTG devices may trigger HNP, if that's been enabled 2138 * between a pair of dual-role devices. That will change roles, such 2139 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral. 2140 * 2141 * Devices on USB hub ports have only one "suspend" state, corresponding 2142 * to ACPI D2, "may cause the device to lose some context". 2143 * State transitions include: 2144 * 2145 * - suspend, resume ... when the VBUS power link stays live 2146 * - suspend, disconnect ... VBUS lost 2147 * 2148 * Once VBUS drop breaks the circuit, the port it's using has to go through 2149 * normal re-enumeration procedures, starting with enabling VBUS power. 2150 * Other than re-initializing the hub (plug/unplug, except for root hubs), 2151 * Linux (2.6) currently has NO mechanisms to initiate that: no khubd 2152 * timer, no SRP, no requests through sysfs. 2153 * 2154 * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when 2155 * the root hub for their bus goes into global suspend ... so we don't 2156 * (falsely) update the device power state to say it suspended. 2157 * 2158 * Returns 0 on success, else negative errno. 2159 */ 2160 int usb_port_suspend(struct usb_device *udev, pm_message_t msg) 2161 { 2162 struct usb_hub *hub = hdev_to_hub(udev->parent); 2163 int port1 = udev->portnum; 2164 int status; 2165 2166 // dev_dbg(hub->intfdev, "suspend port %d\n", port1); 2167 2168 /* enable remote wakeup when appropriate; this lets the device 2169 * wake up the upstream hub (including maybe the root hub). 2170 * 2171 * NOTE: OTG devices may issue remote wakeup (or SRP) even when 2172 * we don't explicitly enable it here. 2173 */ 2174 if (udev->do_remote_wakeup) { 2175 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0), 2176 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE, 2177 USB_DEVICE_REMOTE_WAKEUP, 0, 2178 NULL, 0, 2179 USB_CTRL_SET_TIMEOUT); 2180 if (status) { 2181 dev_dbg(&udev->dev, "won't remote wakeup, status %d\n", 2182 status); 2183 /* bail if autosuspend is requested */ 2184 if (msg.event & PM_EVENT_AUTO) 2185 return status; 2186 } 2187 } 2188 2189 /* see 7.1.7.6 */ 2190 status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND); 2191 if (status) { 2192 dev_dbg(hub->intfdev, "can't suspend port %d, status %d\n", 2193 port1, status); 2194 /* paranoia: "should not happen" */ 2195 if (udev->do_remote_wakeup) 2196 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0), 2197 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE, 2198 USB_DEVICE_REMOTE_WAKEUP, 0, 2199 NULL, 0, 2200 USB_CTRL_SET_TIMEOUT); 2201 } else { 2202 /* device has up to 10 msec to fully suspend */ 2203 dev_dbg(&udev->dev, "usb %ssuspend\n", 2204 (msg.event & PM_EVENT_AUTO ? "auto-" : "")); 2205 usb_set_device_state(udev, USB_STATE_SUSPENDED); 2206 msleep(10); 2207 } 2208 return status; 2209 } 2210 2211 /* 2212 * If the USB "suspend" state is in use (rather than "global suspend"), 2213 * many devices will be individually taken out of suspend state using 2214 * special "resume" signaling. This routine kicks in shortly after 2215 * hardware resume signaling is finished, either because of selective 2216 * resume (by host) or remote wakeup (by device) ... now see what changed 2217 * in the tree that's rooted at this device. 2218 * 2219 * If @udev->reset_resume is set then the device is reset before the 2220 * status check is done. 2221 */ 2222 static int finish_port_resume(struct usb_device *udev) 2223 { 2224 int status = 0; 2225 u16 devstatus; 2226 2227 /* caller owns the udev device lock */ 2228 dev_dbg(&udev->dev, "%s\n", 2229 udev->reset_resume ? "finish reset-resume" : "finish resume"); 2230 2231 /* usb ch9 identifies four variants of SUSPENDED, based on what 2232 * state the device resumes to. Linux currently won't see the 2233 * first two on the host side; they'd be inside hub_port_init() 2234 * during many timeouts, but khubd can't suspend until later. 2235 */ 2236 usb_set_device_state(udev, udev->actconfig 2237 ? USB_STATE_CONFIGURED 2238 : USB_STATE_ADDRESS); 2239 2240 /* 10.5.4.5 says not to reset a suspended port if the attached 2241 * device is enabled for remote wakeup. Hence the reset 2242 * operation is carried out here, after the port has been 2243 * resumed. 2244 */ 2245 if (udev->reset_resume) 2246 retry_reset_resume: 2247 status = usb_reset_and_verify_device(udev); 2248 2249 /* 10.5.4.5 says be sure devices in the tree are still there. 2250 * For now let's assume the device didn't go crazy on resume, 2251 * and device drivers will know about any resume quirks. 2252 */ 2253 if (status == 0) { 2254 devstatus = 0; 2255 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus); 2256 if (status >= 0) 2257 status = (status > 0 ? 0 : -ENODEV); 2258 2259 /* If a normal resume failed, try doing a reset-resume */ 2260 if (status && !udev->reset_resume && udev->persist_enabled) { 2261 dev_dbg(&udev->dev, "retry with reset-resume\n"); 2262 udev->reset_resume = 1; 2263 goto retry_reset_resume; 2264 } 2265 } 2266 2267 if (status) { 2268 dev_dbg(&udev->dev, "gone after usb resume? status %d\n", 2269 status); 2270 } else if (udev->actconfig) { 2271 le16_to_cpus(&devstatus); 2272 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) { 2273 status = usb_control_msg(udev, 2274 usb_sndctrlpipe(udev, 0), 2275 USB_REQ_CLEAR_FEATURE, 2276 USB_RECIP_DEVICE, 2277 USB_DEVICE_REMOTE_WAKEUP, 0, 2278 NULL, 0, 2279 USB_CTRL_SET_TIMEOUT); 2280 if (status) 2281 dev_dbg(&udev->dev, 2282 "disable remote wakeup, status %d\n", 2283 status); 2284 } 2285 status = 0; 2286 } 2287 return status; 2288 } 2289 2290 /* 2291 * usb_port_resume - re-activate a suspended usb device's upstream port 2292 * @udev: device to re-activate, not a root hub 2293 * Context: must be able to sleep; device not locked; pm locks held 2294 * 2295 * This will re-activate the suspended device, increasing power usage 2296 * while letting drivers communicate again with its endpoints. 2297 * USB resume explicitly guarantees that the power session between 2298 * the host and the device is the same as it was when the device 2299 * suspended. 2300 * 2301 * If @udev->reset_resume is set then this routine won't check that the 2302 * port is still enabled. Furthermore, finish_port_resume() above will 2303 * reset @udev. The end result is that a broken power session can be 2304 * recovered and @udev will appear to persist across a loss of VBUS power. 2305 * 2306 * For example, if a host controller doesn't maintain VBUS suspend current 2307 * during a system sleep or is reset when the system wakes up, all the USB 2308 * power sessions below it will be broken. This is especially troublesome 2309 * for mass-storage devices containing mounted filesystems, since the 2310 * device will appear to have disconnected and all the memory mappings 2311 * to it will be lost. Using the USB_PERSIST facility, the device can be 2312 * made to appear as if it had not disconnected. 2313 * 2314 * This facility can be dangerous. Although usb_reset_and_verify_device() makes 2315 * every effort to insure that the same device is present after the 2316 * reset as before, it cannot provide a 100% guarantee. Furthermore it's 2317 * quite possible for a device to remain unaltered but its media to be 2318 * changed. If the user replaces a flash memory card while the system is 2319 * asleep, he will have only himself to blame when the filesystem on the 2320 * new card is corrupted and the system crashes. 2321 * 2322 * Returns 0 on success, else negative errno. 2323 */ 2324 int usb_port_resume(struct usb_device *udev, pm_message_t msg) 2325 { 2326 struct usb_hub *hub = hdev_to_hub(udev->parent); 2327 int port1 = udev->portnum; 2328 int status; 2329 u16 portchange, portstatus; 2330 2331 /* Skip the initial Clear-Suspend step for a remote wakeup */ 2332 status = hub_port_status(hub, port1, &portstatus, &portchange); 2333 if (status == 0 && !(portstatus & USB_PORT_STAT_SUSPEND)) 2334 goto SuspendCleared; 2335 2336 // dev_dbg(hub->intfdev, "resume port %d\n", port1); 2337 2338 set_bit(port1, hub->busy_bits); 2339 2340 /* see 7.1.7.7; affects power usage, but not budgeting */ 2341 status = clear_port_feature(hub->hdev, 2342 port1, USB_PORT_FEAT_SUSPEND); 2343 if (status) { 2344 dev_dbg(hub->intfdev, "can't resume port %d, status %d\n", 2345 port1, status); 2346 } else { 2347 /* drive resume for at least 20 msec */ 2348 dev_dbg(&udev->dev, "usb %sresume\n", 2349 (msg.event & PM_EVENT_AUTO ? "auto-" : "")); 2350 msleep(25); 2351 2352 /* Virtual root hubs can trigger on GET_PORT_STATUS to 2353 * stop resume signaling. Then finish the resume 2354 * sequence. 2355 */ 2356 status = hub_port_status(hub, port1, &portstatus, &portchange); 2357 2358 /* TRSMRCY = 10 msec */ 2359 msleep(10); 2360 } 2361 2362 SuspendCleared: 2363 if (status == 0) { 2364 if (portchange & USB_PORT_STAT_C_SUSPEND) 2365 clear_port_feature(hub->hdev, port1, 2366 USB_PORT_FEAT_C_SUSPEND); 2367 } 2368 2369 clear_bit(port1, hub->busy_bits); 2370 2371 status = check_port_resume_type(udev, 2372 hub, port1, status, portchange, portstatus); 2373 if (status == 0) 2374 status = finish_port_resume(udev); 2375 if (status < 0) { 2376 dev_dbg(&udev->dev, "can't resume, status %d\n", status); 2377 hub_port_logical_disconnect(hub, port1); 2378 } 2379 return status; 2380 } 2381 2382 /* caller has locked udev */ 2383 static int remote_wakeup(struct usb_device *udev) 2384 { 2385 int status = 0; 2386 2387 if (udev->state == USB_STATE_SUSPENDED) { 2388 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-"); 2389 usb_mark_last_busy(udev); 2390 status = usb_external_resume_device(udev, PMSG_REMOTE_RESUME); 2391 } 2392 return status; 2393 } 2394 2395 #else /* CONFIG_USB_SUSPEND */ 2396 2397 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */ 2398 2399 int usb_port_suspend(struct usb_device *udev, pm_message_t msg) 2400 { 2401 return 0; 2402 } 2403 2404 /* However we may need to do a reset-resume */ 2405 2406 int usb_port_resume(struct usb_device *udev, pm_message_t msg) 2407 { 2408 struct usb_hub *hub = hdev_to_hub(udev->parent); 2409 int port1 = udev->portnum; 2410 int status; 2411 u16 portchange, portstatus; 2412 2413 status = hub_port_status(hub, port1, &portstatus, &portchange); 2414 status = check_port_resume_type(udev, 2415 hub, port1, status, portchange, portstatus); 2416 2417 if (status) { 2418 dev_dbg(&udev->dev, "can't resume, status %d\n", status); 2419 hub_port_logical_disconnect(hub, port1); 2420 } else if (udev->reset_resume) { 2421 dev_dbg(&udev->dev, "reset-resume\n"); 2422 status = usb_reset_and_verify_device(udev); 2423 } 2424 return status; 2425 } 2426 2427 static inline int remote_wakeup(struct usb_device *udev) 2428 { 2429 return 0; 2430 } 2431 2432 #endif 2433 2434 static int hub_suspend(struct usb_interface *intf, pm_message_t msg) 2435 { 2436 struct usb_hub *hub = usb_get_intfdata (intf); 2437 struct usb_device *hdev = hub->hdev; 2438 unsigned port1; 2439 2440 /* fail if children aren't already suspended */ 2441 for (port1 = 1; port1 <= hdev->maxchild; port1++) { 2442 struct usb_device *udev; 2443 2444 udev = hdev->children [port1-1]; 2445 if (udev && udev->can_submit) { 2446 if (!(msg.event & PM_EVENT_AUTO)) 2447 dev_dbg(&intf->dev, "port %d nyet suspended\n", 2448 port1); 2449 return -EBUSY; 2450 } 2451 } 2452 2453 dev_dbg(&intf->dev, "%s\n", __func__); 2454 2455 /* stop khubd and related activity */ 2456 hub_quiesce(hub, HUB_SUSPEND); 2457 return 0; 2458 } 2459 2460 static int hub_resume(struct usb_interface *intf) 2461 { 2462 struct usb_hub *hub = usb_get_intfdata(intf); 2463 2464 dev_dbg(&intf->dev, "%s\n", __func__); 2465 hub_activate(hub, HUB_RESUME); 2466 return 0; 2467 } 2468 2469 static int hub_reset_resume(struct usb_interface *intf) 2470 { 2471 struct usb_hub *hub = usb_get_intfdata(intf); 2472 2473 dev_dbg(&intf->dev, "%s\n", __func__); 2474 hub_activate(hub, HUB_RESET_RESUME); 2475 return 0; 2476 } 2477 2478 /** 2479 * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power 2480 * @rhdev: struct usb_device for the root hub 2481 * 2482 * The USB host controller driver calls this function when its root hub 2483 * is resumed and Vbus power has been interrupted or the controller 2484 * has been reset. The routine marks @rhdev as having lost power. 2485 * When the hub driver is resumed it will take notice and carry out 2486 * power-session recovery for all the "USB-PERSIST"-enabled child devices; 2487 * the others will be disconnected. 2488 */ 2489 void usb_root_hub_lost_power(struct usb_device *rhdev) 2490 { 2491 dev_warn(&rhdev->dev, "root hub lost power or was reset\n"); 2492 rhdev->reset_resume = 1; 2493 } 2494 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power); 2495 2496 #else /* CONFIG_PM */ 2497 2498 static inline int remote_wakeup(struct usb_device *udev) 2499 { 2500 return 0; 2501 } 2502 2503 #define hub_suspend NULL 2504 #define hub_resume NULL 2505 #define hub_reset_resume NULL 2506 #endif 2507 2508 2509 /* USB 2.0 spec, 7.1.7.3 / fig 7-29: 2510 * 2511 * Between connect detection and reset signaling there must be a delay 2512 * of 100ms at least for debounce and power-settling. The corresponding 2513 * timer shall restart whenever the downstream port detects a disconnect. 2514 * 2515 * Apparently there are some bluetooth and irda-dongles and a number of 2516 * low-speed devices for which this debounce period may last over a second. 2517 * Not covered by the spec - but easy to deal with. 2518 * 2519 * This implementation uses a 1500ms total debounce timeout; if the 2520 * connection isn't stable by then it returns -ETIMEDOUT. It checks 2521 * every 25ms for transient disconnects. When the port status has been 2522 * unchanged for 100ms it returns the port status. 2523 */ 2524 static int hub_port_debounce(struct usb_hub *hub, int port1) 2525 { 2526 int ret; 2527 int total_time, stable_time = 0; 2528 u16 portchange, portstatus; 2529 unsigned connection = 0xffff; 2530 2531 for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) { 2532 ret = hub_port_status(hub, port1, &portstatus, &portchange); 2533 if (ret < 0) 2534 return ret; 2535 2536 if (!(portchange & USB_PORT_STAT_C_CONNECTION) && 2537 (portstatus & USB_PORT_STAT_CONNECTION) == connection) { 2538 stable_time += HUB_DEBOUNCE_STEP; 2539 if (stable_time >= HUB_DEBOUNCE_STABLE) 2540 break; 2541 } else { 2542 stable_time = 0; 2543 connection = portstatus & USB_PORT_STAT_CONNECTION; 2544 } 2545 2546 if (portchange & USB_PORT_STAT_C_CONNECTION) { 2547 clear_port_feature(hub->hdev, port1, 2548 USB_PORT_FEAT_C_CONNECTION); 2549 } 2550 2551 if (total_time >= HUB_DEBOUNCE_TIMEOUT) 2552 break; 2553 msleep(HUB_DEBOUNCE_STEP); 2554 } 2555 2556 dev_dbg (hub->intfdev, 2557 "debounce: port %d: total %dms stable %dms status 0x%x\n", 2558 port1, total_time, stable_time, portstatus); 2559 2560 if (stable_time < HUB_DEBOUNCE_STABLE) 2561 return -ETIMEDOUT; 2562 return portstatus; 2563 } 2564 2565 void usb_ep0_reinit(struct usb_device *udev) 2566 { 2567 usb_disable_endpoint(udev, 0 + USB_DIR_IN, true); 2568 usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true); 2569 usb_enable_endpoint(udev, &udev->ep0, true); 2570 } 2571 EXPORT_SYMBOL_GPL(usb_ep0_reinit); 2572 2573 #define usb_sndaddr0pipe() (PIPE_CONTROL << 30) 2574 #define usb_rcvaddr0pipe() ((PIPE_CONTROL << 30) | USB_DIR_IN) 2575 2576 static int hub_set_address(struct usb_device *udev, int devnum) 2577 { 2578 int retval; 2579 struct usb_hcd *hcd = bus_to_hcd(udev->bus); 2580 2581 /* 2582 * The host controller will choose the device address, 2583 * instead of the core having chosen it earlier 2584 */ 2585 if (!hcd->driver->address_device && devnum <= 1) 2586 return -EINVAL; 2587 if (udev->state == USB_STATE_ADDRESS) 2588 return 0; 2589 if (udev->state != USB_STATE_DEFAULT) 2590 return -EINVAL; 2591 if (hcd->driver->address_device) { 2592 retval = hcd->driver->address_device(hcd, udev); 2593 } else { 2594 retval = usb_control_msg(udev, usb_sndaddr0pipe(), 2595 USB_REQ_SET_ADDRESS, 0, devnum, 0, 2596 NULL, 0, USB_CTRL_SET_TIMEOUT); 2597 if (retval == 0) 2598 update_address(udev, devnum); 2599 } 2600 if (retval == 0) { 2601 /* Device now using proper address. */ 2602 usb_set_device_state(udev, USB_STATE_ADDRESS); 2603 usb_ep0_reinit(udev); 2604 } 2605 return retval; 2606 } 2607 2608 /* Reset device, (re)assign address, get device descriptor. 2609 * Device connection must be stable, no more debouncing needed. 2610 * Returns device in USB_STATE_ADDRESS, except on error. 2611 * 2612 * If this is called for an already-existing device (as part of 2613 * usb_reset_and_verify_device), the caller must own the device lock. For a 2614 * newly detected device that is not accessible through any global 2615 * pointers, it's not necessary to lock the device. 2616 */ 2617 static int 2618 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1, 2619 int retry_counter) 2620 { 2621 static DEFINE_MUTEX(usb_address0_mutex); 2622 2623 struct usb_device *hdev = hub->hdev; 2624 struct usb_hcd *hcd = bus_to_hcd(hdev->bus); 2625 int i, j, retval; 2626 unsigned delay = HUB_SHORT_RESET_TIME; 2627 enum usb_device_speed oldspeed = udev->speed; 2628 char *speed, *type; 2629 int devnum = udev->devnum; 2630 2631 /* root hub ports have a slightly longer reset period 2632 * (from USB 2.0 spec, section 7.1.7.5) 2633 */ 2634 if (!hdev->parent) { 2635 delay = HUB_ROOT_RESET_TIME; 2636 if (port1 == hdev->bus->otg_port) 2637 hdev->bus->b_hnp_enable = 0; 2638 } 2639 2640 /* Some low speed devices have problems with the quick delay, so */ 2641 /* be a bit pessimistic with those devices. RHbug #23670 */ 2642 if (oldspeed == USB_SPEED_LOW) 2643 delay = HUB_LONG_RESET_TIME; 2644 2645 mutex_lock(&usb_address0_mutex); 2646 2647 if ((hcd->driver->flags & HCD_USB3) && udev->config) { 2648 /* FIXME this will need special handling by the xHCI driver. */ 2649 dev_dbg(&udev->dev, 2650 "xHCI reset of configured device " 2651 "not supported yet.\n"); 2652 retval = -EINVAL; 2653 goto fail; 2654 } else if (!udev->config && oldspeed == USB_SPEED_SUPER) { 2655 /* Don't reset USB 3.0 devices during an initial setup */ 2656 usb_set_device_state(udev, USB_STATE_DEFAULT); 2657 } else { 2658 /* Reset the device; full speed may morph to high speed */ 2659 /* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */ 2660 retval = hub_port_reset(hub, port1, udev, delay); 2661 if (retval < 0) /* error or disconnect */ 2662 goto fail; 2663 /* success, speed is known */ 2664 } 2665 retval = -ENODEV; 2666 2667 if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) { 2668 dev_dbg(&udev->dev, "device reset changed speed!\n"); 2669 goto fail; 2670 } 2671 oldspeed = udev->speed; 2672 2673 /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ... 2674 * it's fixed size except for full speed devices. 2675 * For Wireless USB devices, ep0 max packet is always 512 (tho 2676 * reported as 0xff in the device descriptor). WUSB1.0[4.8.1]. 2677 */ 2678 switch (udev->speed) { 2679 case USB_SPEED_SUPER: 2680 case USB_SPEED_VARIABLE: /* fixed at 512 */ 2681 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512); 2682 break; 2683 case USB_SPEED_HIGH: /* fixed at 64 */ 2684 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64); 2685 break; 2686 case USB_SPEED_FULL: /* 8, 16, 32, or 64 */ 2687 /* to determine the ep0 maxpacket size, try to read 2688 * the device descriptor to get bMaxPacketSize0 and 2689 * then correct our initial guess. 2690 */ 2691 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64); 2692 break; 2693 case USB_SPEED_LOW: /* fixed at 8 */ 2694 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(8); 2695 break; 2696 default: 2697 goto fail; 2698 } 2699 2700 type = ""; 2701 switch (udev->speed) { 2702 case USB_SPEED_LOW: speed = "low"; break; 2703 case USB_SPEED_FULL: speed = "full"; break; 2704 case USB_SPEED_HIGH: speed = "high"; break; 2705 case USB_SPEED_SUPER: 2706 speed = "super"; 2707 break; 2708 case USB_SPEED_VARIABLE: 2709 speed = "variable"; 2710 type = "Wireless "; 2711 break; 2712 default: speed = "?"; break; 2713 } 2714 if (udev->speed != USB_SPEED_SUPER) 2715 dev_info(&udev->dev, 2716 "%s %s speed %sUSB device using %s and address %d\n", 2717 (udev->config) ? "reset" : "new", speed, type, 2718 udev->bus->controller->driver->name, devnum); 2719 2720 /* Set up TT records, if needed */ 2721 if (hdev->tt) { 2722 udev->tt = hdev->tt; 2723 udev->ttport = hdev->ttport; 2724 } else if (udev->speed != USB_SPEED_HIGH 2725 && hdev->speed == USB_SPEED_HIGH) { 2726 udev->tt = &hub->tt; 2727 udev->ttport = port1; 2728 } 2729 2730 /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way? 2731 * Because device hardware and firmware is sometimes buggy in 2732 * this area, and this is how Linux has done it for ages. 2733 * Change it cautiously. 2734 * 2735 * NOTE: If USE_NEW_SCHEME() is true we will start by issuing 2736 * a 64-byte GET_DESCRIPTOR request. This is what Windows does, 2737 * so it may help with some non-standards-compliant devices. 2738 * Otherwise we start with SET_ADDRESS and then try to read the 2739 * first 8 bytes of the device descriptor to get the ep0 maxpacket 2740 * value. 2741 */ 2742 for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) { 2743 /* 2744 * An xHCI controller cannot send any packets to a device until 2745 * a set address command successfully completes. 2746 */ 2747 if (USE_NEW_SCHEME(retry_counter) && !(hcd->driver->flags & HCD_USB3)) { 2748 struct usb_device_descriptor *buf; 2749 int r = 0; 2750 2751 #define GET_DESCRIPTOR_BUFSIZE 64 2752 buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO); 2753 if (!buf) { 2754 retval = -ENOMEM; 2755 continue; 2756 } 2757 2758 /* Retry on all errors; some devices are flakey. 2759 * 255 is for WUSB devices, we actually need to use 2760 * 512 (WUSB1.0[4.8.1]). 2761 */ 2762 for (j = 0; j < 3; ++j) { 2763 buf->bMaxPacketSize0 = 0; 2764 r = usb_control_msg(udev, usb_rcvaddr0pipe(), 2765 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN, 2766 USB_DT_DEVICE << 8, 0, 2767 buf, GET_DESCRIPTOR_BUFSIZE, 2768 initial_descriptor_timeout); 2769 switch (buf->bMaxPacketSize0) { 2770 case 8: case 16: case 32: case 64: case 255: 2771 if (buf->bDescriptorType == 2772 USB_DT_DEVICE) { 2773 r = 0; 2774 break; 2775 } 2776 /* FALL THROUGH */ 2777 default: 2778 if (r == 0) 2779 r = -EPROTO; 2780 break; 2781 } 2782 if (r == 0) 2783 break; 2784 } 2785 udev->descriptor.bMaxPacketSize0 = 2786 buf->bMaxPacketSize0; 2787 kfree(buf); 2788 2789 retval = hub_port_reset(hub, port1, udev, delay); 2790 if (retval < 0) /* error or disconnect */ 2791 goto fail; 2792 if (oldspeed != udev->speed) { 2793 dev_dbg(&udev->dev, 2794 "device reset changed speed!\n"); 2795 retval = -ENODEV; 2796 goto fail; 2797 } 2798 if (r) { 2799 dev_err(&udev->dev, 2800 "device descriptor read/64, error %d\n", 2801 r); 2802 retval = -EMSGSIZE; 2803 continue; 2804 } 2805 #undef GET_DESCRIPTOR_BUFSIZE 2806 } 2807 2808 /* 2809 * If device is WUSB, we already assigned an 2810 * unauthorized address in the Connect Ack sequence; 2811 * authorization will assign the final address. 2812 */ 2813 if (udev->wusb == 0) { 2814 for (j = 0; j < SET_ADDRESS_TRIES; ++j) { 2815 retval = hub_set_address(udev, devnum); 2816 if (retval >= 0) 2817 break; 2818 msleep(200); 2819 } 2820 if (retval < 0) { 2821 dev_err(&udev->dev, 2822 "device not accepting address %d, error %d\n", 2823 devnum, retval); 2824 goto fail; 2825 } 2826 if (udev->speed == USB_SPEED_SUPER) { 2827 devnum = udev->devnum; 2828 dev_info(&udev->dev, 2829 "%s SuperSpeed USB device using %s and address %d\n", 2830 (udev->config) ? "reset" : "new", 2831 udev->bus->controller->driver->name, devnum); 2832 } 2833 2834 /* cope with hardware quirkiness: 2835 * - let SET_ADDRESS settle, some device hardware wants it 2836 * - read ep0 maxpacket even for high and low speed, 2837 */ 2838 msleep(10); 2839 if (USE_NEW_SCHEME(retry_counter) && !(hcd->driver->flags & HCD_USB3)) 2840 break; 2841 } 2842 2843 retval = usb_get_device_descriptor(udev, 8); 2844 if (retval < 8) { 2845 dev_err(&udev->dev, 2846 "device descriptor read/8, error %d\n", 2847 retval); 2848 if (retval >= 0) 2849 retval = -EMSGSIZE; 2850 } else { 2851 retval = 0; 2852 break; 2853 } 2854 } 2855 if (retval) 2856 goto fail; 2857 2858 if (udev->descriptor.bMaxPacketSize0 == 0xff || 2859 udev->speed == USB_SPEED_SUPER) 2860 i = 512; 2861 else 2862 i = udev->descriptor.bMaxPacketSize0; 2863 if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) { 2864 if (udev->speed != USB_SPEED_FULL || 2865 !(i == 8 || i == 16 || i == 32 || i == 64)) { 2866 dev_err(&udev->dev, "ep0 maxpacket = %d\n", i); 2867 retval = -EMSGSIZE; 2868 goto fail; 2869 } 2870 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i); 2871 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i); 2872 usb_ep0_reinit(udev); 2873 } 2874 2875 retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE); 2876 if (retval < (signed)sizeof(udev->descriptor)) { 2877 dev_err(&udev->dev, "device descriptor read/all, error %d\n", 2878 retval); 2879 if (retval >= 0) 2880 retval = -ENOMSG; 2881 goto fail; 2882 } 2883 2884 retval = 0; 2885 2886 fail: 2887 if (retval) { 2888 hub_port_disable(hub, port1, 0); 2889 update_address(udev, devnum); /* for disconnect processing */ 2890 } 2891 mutex_unlock(&usb_address0_mutex); 2892 return retval; 2893 } 2894 2895 static void 2896 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1) 2897 { 2898 struct usb_qualifier_descriptor *qual; 2899 int status; 2900 2901 qual = kmalloc (sizeof *qual, GFP_KERNEL); 2902 if (qual == NULL) 2903 return; 2904 2905 status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0, 2906 qual, sizeof *qual); 2907 if (status == sizeof *qual) { 2908 dev_info(&udev->dev, "not running at top speed; " 2909 "connect to a high speed hub\n"); 2910 /* hub LEDs are probably harder to miss than syslog */ 2911 if (hub->has_indicators) { 2912 hub->indicator[port1-1] = INDICATOR_GREEN_BLINK; 2913 schedule_delayed_work (&hub->leds, 0); 2914 } 2915 } 2916 kfree(qual); 2917 } 2918 2919 static unsigned 2920 hub_power_remaining (struct usb_hub *hub) 2921 { 2922 struct usb_device *hdev = hub->hdev; 2923 int remaining; 2924 int port1; 2925 2926 if (!hub->limited_power) 2927 return 0; 2928 2929 remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent; 2930 for (port1 = 1; port1 <= hdev->maxchild; ++port1) { 2931 struct usb_device *udev = hdev->children[port1 - 1]; 2932 int delta; 2933 2934 if (!udev) 2935 continue; 2936 2937 /* Unconfigured devices may not use more than 100mA, 2938 * or 8mA for OTG ports */ 2939 if (udev->actconfig) 2940 delta = udev->actconfig->desc.bMaxPower * 2; 2941 else if (port1 != udev->bus->otg_port || hdev->parent) 2942 delta = 100; 2943 else 2944 delta = 8; 2945 if (delta > hub->mA_per_port) 2946 dev_warn(&udev->dev, 2947 "%dmA is over %umA budget for port %d!\n", 2948 delta, hub->mA_per_port, port1); 2949 remaining -= delta; 2950 } 2951 if (remaining < 0) { 2952 dev_warn(hub->intfdev, "%dmA over power budget!\n", 2953 - remaining); 2954 remaining = 0; 2955 } 2956 return remaining; 2957 } 2958 2959 /* Handle physical or logical connection change events. 2960 * This routine is called when: 2961 * a port connection-change occurs; 2962 * a port enable-change occurs (often caused by EMI); 2963 * usb_reset_and_verify_device() encounters changed descriptors (as from 2964 * a firmware download) 2965 * caller already locked the hub 2966 */ 2967 static void hub_port_connect_change(struct usb_hub *hub, int port1, 2968 u16 portstatus, u16 portchange) 2969 { 2970 struct usb_device *hdev = hub->hdev; 2971 struct device *hub_dev = hub->intfdev; 2972 struct usb_hcd *hcd = bus_to_hcd(hdev->bus); 2973 unsigned wHubCharacteristics = 2974 le16_to_cpu(hub->descriptor->wHubCharacteristics); 2975 struct usb_device *udev; 2976 int status, i; 2977 2978 dev_dbg (hub_dev, 2979 "port %d, status %04x, change %04x, %s\n", 2980 port1, portstatus, portchange, portspeed (portstatus)); 2981 2982 if (hub->has_indicators) { 2983 set_port_led(hub, port1, HUB_LED_AUTO); 2984 hub->indicator[port1-1] = INDICATOR_AUTO; 2985 } 2986 2987 #ifdef CONFIG_USB_OTG 2988 /* during HNP, don't repeat the debounce */ 2989 if (hdev->bus->is_b_host) 2990 portchange &= ~(USB_PORT_STAT_C_CONNECTION | 2991 USB_PORT_STAT_C_ENABLE); 2992 #endif 2993 2994 /* Try to resuscitate an existing device */ 2995 udev = hdev->children[port1-1]; 2996 if ((portstatus & USB_PORT_STAT_CONNECTION) && udev && 2997 udev->state != USB_STATE_NOTATTACHED) { 2998 usb_lock_device(udev); 2999 if (portstatus & USB_PORT_STAT_ENABLE) { 3000 status = 0; /* Nothing to do */ 3001 3002 #ifdef CONFIG_USB_SUSPEND 3003 } else if (udev->state == USB_STATE_SUSPENDED && 3004 udev->persist_enabled) { 3005 /* For a suspended device, treat this as a 3006 * remote wakeup event. 3007 */ 3008 status = remote_wakeup(udev); 3009 #endif 3010 3011 } else { 3012 status = -ENODEV; /* Don't resuscitate */ 3013 } 3014 usb_unlock_device(udev); 3015 3016 if (status == 0) { 3017 clear_bit(port1, hub->change_bits); 3018 return; 3019 } 3020 } 3021 3022 /* Disconnect any existing devices under this port */ 3023 if (udev) 3024 usb_disconnect(&hdev->children[port1-1]); 3025 clear_bit(port1, hub->change_bits); 3026 3027 /* We can forget about a "removed" device when there's a physical 3028 * disconnect or the connect status changes. 3029 */ 3030 if (!(portstatus & USB_PORT_STAT_CONNECTION) || 3031 (portchange & USB_PORT_STAT_C_CONNECTION)) 3032 clear_bit(port1, hub->removed_bits); 3033 3034 if (portchange & (USB_PORT_STAT_C_CONNECTION | 3035 USB_PORT_STAT_C_ENABLE)) { 3036 status = hub_port_debounce(hub, port1); 3037 if (status < 0) { 3038 if (printk_ratelimit()) 3039 dev_err(hub_dev, "connect-debounce failed, " 3040 "port %d disabled\n", port1); 3041 portstatus &= ~USB_PORT_STAT_CONNECTION; 3042 } else { 3043 portstatus = status; 3044 } 3045 } 3046 3047 /* Return now if debouncing failed or nothing is connected or 3048 * the device was "removed". 3049 */ 3050 if (!(portstatus & USB_PORT_STAT_CONNECTION) || 3051 test_bit(port1, hub->removed_bits)) { 3052 3053 /* maybe switch power back on (e.g. root hub was reset) */ 3054 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2 3055 && !(portstatus & (1 << USB_PORT_FEAT_POWER))) 3056 set_port_feature(hdev, port1, USB_PORT_FEAT_POWER); 3057 3058 if (portstatus & USB_PORT_STAT_ENABLE) 3059 goto done; 3060 return; 3061 } 3062 3063 for (i = 0; i < SET_CONFIG_TRIES; i++) { 3064 3065 /* reallocate for each attempt, since references 3066 * to the previous one can escape in various ways 3067 */ 3068 udev = usb_alloc_dev(hdev, hdev->bus, port1); 3069 if (!udev) { 3070 dev_err (hub_dev, 3071 "couldn't allocate port %d usb_device\n", 3072 port1); 3073 goto done; 3074 } 3075 3076 usb_set_device_state(udev, USB_STATE_POWERED); 3077 udev->bus_mA = hub->mA_per_port; 3078 udev->level = hdev->level + 1; 3079 udev->wusb = hub_is_wusb(hub); 3080 3081 /* 3082 * USB 3.0 devices are reset automatically before the connect 3083 * port status change appears, and the root hub port status 3084 * shows the correct speed. We also get port change 3085 * notifications for USB 3.0 devices from the USB 3.0 portion of 3086 * an external USB 3.0 hub, but this isn't handled correctly yet 3087 * FIXME. 3088 */ 3089 3090 if (!(hcd->driver->flags & HCD_USB3)) 3091 udev->speed = USB_SPEED_UNKNOWN; 3092 else if ((hdev->parent == NULL) && 3093 (portstatus & (1 << USB_PORT_FEAT_SUPERSPEED))) 3094 udev->speed = USB_SPEED_SUPER; 3095 else 3096 udev->speed = USB_SPEED_UNKNOWN; 3097 3098 /* 3099 * xHCI needs to issue an address device command later 3100 * in the hub_port_init sequence for SS/HS/FS/LS devices. 3101 */ 3102 if (!(hcd->driver->flags & HCD_USB3)) { 3103 /* set the address */ 3104 choose_address(udev); 3105 if (udev->devnum <= 0) { 3106 status = -ENOTCONN; /* Don't retry */ 3107 goto loop; 3108 } 3109 } 3110 3111 /* reset (non-USB 3.0 devices) and get descriptor */ 3112 status = hub_port_init(hub, udev, port1, i); 3113 if (status < 0) 3114 goto loop; 3115 3116 /* consecutive bus-powered hubs aren't reliable; they can 3117 * violate the voltage drop budget. if the new child has 3118 * a "powered" LED, users should notice we didn't enable it 3119 * (without reading syslog), even without per-port LEDs 3120 * on the parent. 3121 */ 3122 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB 3123 && udev->bus_mA <= 100) { 3124 u16 devstat; 3125 3126 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, 3127 &devstat); 3128 if (status < 2) { 3129 dev_dbg(&udev->dev, "get status %d ?\n", status); 3130 goto loop_disable; 3131 } 3132 le16_to_cpus(&devstat); 3133 if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) { 3134 dev_err(&udev->dev, 3135 "can't connect bus-powered hub " 3136 "to this port\n"); 3137 if (hub->has_indicators) { 3138 hub->indicator[port1-1] = 3139 INDICATOR_AMBER_BLINK; 3140 schedule_delayed_work (&hub->leds, 0); 3141 } 3142 status = -ENOTCONN; /* Don't retry */ 3143 goto loop_disable; 3144 } 3145 } 3146 3147 /* check for devices running slower than they could */ 3148 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200 3149 && udev->speed == USB_SPEED_FULL 3150 && highspeed_hubs != 0) 3151 check_highspeed (hub, udev, port1); 3152 3153 /* Store the parent's children[] pointer. At this point 3154 * udev becomes globally accessible, although presumably 3155 * no one will look at it until hdev is unlocked. 3156 */ 3157 status = 0; 3158 3159 /* We mustn't add new devices if the parent hub has 3160 * been disconnected; we would race with the 3161 * recursively_mark_NOTATTACHED() routine. 3162 */ 3163 spin_lock_irq(&device_state_lock); 3164 if (hdev->state == USB_STATE_NOTATTACHED) 3165 status = -ENOTCONN; 3166 else 3167 hdev->children[port1-1] = udev; 3168 spin_unlock_irq(&device_state_lock); 3169 3170 /* Run it through the hoops (find a driver, etc) */ 3171 if (!status) { 3172 status = usb_new_device(udev); 3173 if (status) { 3174 spin_lock_irq(&device_state_lock); 3175 hdev->children[port1-1] = NULL; 3176 spin_unlock_irq(&device_state_lock); 3177 } 3178 } 3179 3180 if (status) 3181 goto loop_disable; 3182 3183 status = hub_power_remaining(hub); 3184 if (status) 3185 dev_dbg(hub_dev, "%dmA power budget left\n", status); 3186 3187 return; 3188 3189 loop_disable: 3190 hub_port_disable(hub, port1, 1); 3191 loop: 3192 usb_ep0_reinit(udev); 3193 release_address(udev); 3194 usb_put_dev(udev); 3195 if ((status == -ENOTCONN) || (status == -ENOTSUPP)) 3196 break; 3197 } 3198 if (hub->hdev->parent || 3199 !hcd->driver->port_handed_over || 3200 !(hcd->driver->port_handed_over)(hcd, port1)) 3201 dev_err(hub_dev, "unable to enumerate USB device on port %d\n", 3202 port1); 3203 3204 done: 3205 hub_port_disable(hub, port1, 1); 3206 if (hcd->driver->relinquish_port && !hub->hdev->parent) 3207 hcd->driver->relinquish_port(hcd, port1); 3208 } 3209 3210 static void hub_events(void) 3211 { 3212 struct list_head *tmp; 3213 struct usb_device *hdev; 3214 struct usb_interface *intf; 3215 struct usb_hub *hub; 3216 struct device *hub_dev; 3217 u16 hubstatus; 3218 u16 hubchange; 3219 u16 portstatus; 3220 u16 portchange; 3221 int i, ret; 3222 int connect_change; 3223 3224 /* 3225 * We restart the list every time to avoid a deadlock with 3226 * deleting hubs downstream from this one. This should be 3227 * safe since we delete the hub from the event list. 3228 * Not the most efficient, but avoids deadlocks. 3229 */ 3230 while (1) { 3231 3232 /* Grab the first entry at the beginning of the list */ 3233 spin_lock_irq(&hub_event_lock); 3234 if (list_empty(&hub_event_list)) { 3235 spin_unlock_irq(&hub_event_lock); 3236 break; 3237 } 3238 3239 tmp = hub_event_list.next; 3240 list_del_init(tmp); 3241 3242 hub = list_entry(tmp, struct usb_hub, event_list); 3243 kref_get(&hub->kref); 3244 spin_unlock_irq(&hub_event_lock); 3245 3246 hdev = hub->hdev; 3247 hub_dev = hub->intfdev; 3248 intf = to_usb_interface(hub_dev); 3249 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n", 3250 hdev->state, hub->descriptor 3251 ? hub->descriptor->bNbrPorts 3252 : 0, 3253 /* NOTE: expects max 15 ports... */ 3254 (u16) hub->change_bits[0], 3255 (u16) hub->event_bits[0]); 3256 3257 /* Lock the device, then check to see if we were 3258 * disconnected while waiting for the lock to succeed. */ 3259 usb_lock_device(hdev); 3260 if (unlikely(hub->disconnected)) 3261 goto loop2; 3262 3263 /* If the hub has died, clean up after it */ 3264 if (hdev->state == USB_STATE_NOTATTACHED) { 3265 hub->error = -ENODEV; 3266 hub_quiesce(hub, HUB_DISCONNECT); 3267 goto loop; 3268 } 3269 3270 /* Autoresume */ 3271 ret = usb_autopm_get_interface(intf); 3272 if (ret) { 3273 dev_dbg(hub_dev, "Can't autoresume: %d\n", ret); 3274 goto loop; 3275 } 3276 3277 /* If this is an inactive hub, do nothing */ 3278 if (hub->quiescing) 3279 goto loop_autopm; 3280 3281 if (hub->error) { 3282 dev_dbg (hub_dev, "resetting for error %d\n", 3283 hub->error); 3284 3285 ret = usb_reset_device(hdev); 3286 if (ret) { 3287 dev_dbg (hub_dev, 3288 "error resetting hub: %d\n", ret); 3289 goto loop_autopm; 3290 } 3291 3292 hub->nerrors = 0; 3293 hub->error = 0; 3294 } 3295 3296 /* deal with port status changes */ 3297 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) { 3298 if (test_bit(i, hub->busy_bits)) 3299 continue; 3300 connect_change = test_bit(i, hub->change_bits); 3301 if (!test_and_clear_bit(i, hub->event_bits) && 3302 !connect_change) 3303 continue; 3304 3305 ret = hub_port_status(hub, i, 3306 &portstatus, &portchange); 3307 if (ret < 0) 3308 continue; 3309 3310 if (portchange & USB_PORT_STAT_C_CONNECTION) { 3311 clear_port_feature(hdev, i, 3312 USB_PORT_FEAT_C_CONNECTION); 3313 connect_change = 1; 3314 } 3315 3316 if (portchange & USB_PORT_STAT_C_ENABLE) { 3317 if (!connect_change) 3318 dev_dbg (hub_dev, 3319 "port %d enable change, " 3320 "status %08x\n", 3321 i, portstatus); 3322 clear_port_feature(hdev, i, 3323 USB_PORT_FEAT_C_ENABLE); 3324 3325 /* 3326 * EM interference sometimes causes badly 3327 * shielded USB devices to be shutdown by 3328 * the hub, this hack enables them again. 3329 * Works at least with mouse driver. 3330 */ 3331 if (!(portstatus & USB_PORT_STAT_ENABLE) 3332 && !connect_change 3333 && hdev->children[i-1]) { 3334 dev_err (hub_dev, 3335 "port %i " 3336 "disabled by hub (EMI?), " 3337 "re-enabling...\n", 3338 i); 3339 connect_change = 1; 3340 } 3341 } 3342 3343 if (portchange & USB_PORT_STAT_C_SUSPEND) { 3344 struct usb_device *udev; 3345 3346 clear_port_feature(hdev, i, 3347 USB_PORT_FEAT_C_SUSPEND); 3348 udev = hdev->children[i-1]; 3349 if (udev) { 3350 /* TRSMRCY = 10 msec */ 3351 msleep(10); 3352 3353 usb_lock_device(udev); 3354 ret = remote_wakeup(hdev-> 3355 children[i-1]); 3356 usb_unlock_device(udev); 3357 if (ret < 0) 3358 connect_change = 1; 3359 } else { 3360 ret = -ENODEV; 3361 hub_port_disable(hub, i, 1); 3362 } 3363 dev_dbg (hub_dev, 3364 "resume on port %d, status %d\n", 3365 i, ret); 3366 } 3367 3368 if (portchange & USB_PORT_STAT_C_OVERCURRENT) { 3369 dev_err (hub_dev, 3370 "over-current change on port %d\n", 3371 i); 3372 clear_port_feature(hdev, i, 3373 USB_PORT_FEAT_C_OVER_CURRENT); 3374 hub_power_on(hub, true); 3375 } 3376 3377 if (portchange & USB_PORT_STAT_C_RESET) { 3378 dev_dbg (hub_dev, 3379 "reset change on port %d\n", 3380 i); 3381 clear_port_feature(hdev, i, 3382 USB_PORT_FEAT_C_RESET); 3383 } 3384 3385 if (connect_change) 3386 hub_port_connect_change(hub, i, 3387 portstatus, portchange); 3388 } /* end for i */ 3389 3390 /* deal with hub status changes */ 3391 if (test_and_clear_bit(0, hub->event_bits) == 0) 3392 ; /* do nothing */ 3393 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0) 3394 dev_err (hub_dev, "get_hub_status failed\n"); 3395 else { 3396 if (hubchange & HUB_CHANGE_LOCAL_POWER) { 3397 dev_dbg (hub_dev, "power change\n"); 3398 clear_hub_feature(hdev, C_HUB_LOCAL_POWER); 3399 if (hubstatus & HUB_STATUS_LOCAL_POWER) 3400 /* FIXME: Is this always true? */ 3401 hub->limited_power = 1; 3402 else 3403 hub->limited_power = 0; 3404 } 3405 if (hubchange & HUB_CHANGE_OVERCURRENT) { 3406 dev_dbg (hub_dev, "overcurrent change\n"); 3407 msleep(500); /* Cool down */ 3408 clear_hub_feature(hdev, C_HUB_OVER_CURRENT); 3409 hub_power_on(hub, true); 3410 } 3411 } 3412 3413 loop_autopm: 3414 /* Balance the usb_autopm_get_interface() above */ 3415 usb_autopm_put_interface_no_suspend(intf); 3416 loop: 3417 /* Balance the usb_autopm_get_interface_no_resume() in 3418 * kick_khubd() and allow autosuspend. 3419 */ 3420 usb_autopm_put_interface(intf); 3421 loop2: 3422 usb_unlock_device(hdev); 3423 kref_put(&hub->kref, hub_release); 3424 3425 } /* end while (1) */ 3426 } 3427 3428 static int hub_thread(void *__unused) 3429 { 3430 /* khubd needs to be freezable to avoid intefering with USB-PERSIST 3431 * port handover. Otherwise it might see that a full-speed device 3432 * was gone before the EHCI controller had handed its port over to 3433 * the companion full-speed controller. 3434 */ 3435 set_freezable(); 3436 3437 do { 3438 hub_events(); 3439 wait_event_freezable(khubd_wait, 3440 !list_empty(&hub_event_list) || 3441 kthread_should_stop()); 3442 } while (!kthread_should_stop() || !list_empty(&hub_event_list)); 3443 3444 pr_debug("%s: khubd exiting\n", usbcore_name); 3445 return 0; 3446 } 3447 3448 static struct usb_device_id hub_id_table [] = { 3449 { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS, 3450 .bDeviceClass = USB_CLASS_HUB}, 3451 { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS, 3452 .bInterfaceClass = USB_CLASS_HUB}, 3453 { } /* Terminating entry */ 3454 }; 3455 3456 MODULE_DEVICE_TABLE (usb, hub_id_table); 3457 3458 static struct usb_driver hub_driver = { 3459 .name = "hub", 3460 .probe = hub_probe, 3461 .disconnect = hub_disconnect, 3462 .suspend = hub_suspend, 3463 .resume = hub_resume, 3464 .reset_resume = hub_reset_resume, 3465 .pre_reset = hub_pre_reset, 3466 .post_reset = hub_post_reset, 3467 .ioctl = hub_ioctl, 3468 .id_table = hub_id_table, 3469 .supports_autosuspend = 1, 3470 }; 3471 3472 int usb_hub_init(void) 3473 { 3474 if (usb_register(&hub_driver) < 0) { 3475 printk(KERN_ERR "%s: can't register hub driver\n", 3476 usbcore_name); 3477 return -1; 3478 } 3479 3480 khubd_task = kthread_run(hub_thread, NULL, "khubd"); 3481 if (!IS_ERR(khubd_task)) 3482 return 0; 3483 3484 /* Fall through if kernel_thread failed */ 3485 usb_deregister(&hub_driver); 3486 printk(KERN_ERR "%s: can't start khubd\n", usbcore_name); 3487 3488 return -1; 3489 } 3490 3491 void usb_hub_cleanup(void) 3492 { 3493 kthread_stop(khubd_task); 3494 3495 /* 3496 * Hub resources are freed for us by usb_deregister. It calls 3497 * usb_driver_purge on every device which in turn calls that 3498 * devices disconnect function if it is using this driver. 3499 * The hub_disconnect function takes care of releasing the 3500 * individual hub resources. -greg 3501 */ 3502 usb_deregister(&hub_driver); 3503 } /* usb_hub_cleanup() */ 3504 3505 static int descriptors_changed(struct usb_device *udev, 3506 struct usb_device_descriptor *old_device_descriptor) 3507 { 3508 int changed = 0; 3509 unsigned index; 3510 unsigned serial_len = 0; 3511 unsigned len; 3512 unsigned old_length; 3513 int length; 3514 char *buf; 3515 3516 if (memcmp(&udev->descriptor, old_device_descriptor, 3517 sizeof(*old_device_descriptor)) != 0) 3518 return 1; 3519 3520 /* Since the idVendor, idProduct, and bcdDevice values in the 3521 * device descriptor haven't changed, we will assume the 3522 * Manufacturer and Product strings haven't changed either. 3523 * But the SerialNumber string could be different (e.g., a 3524 * different flash card of the same brand). 3525 */ 3526 if (udev->serial) 3527 serial_len = strlen(udev->serial) + 1; 3528 3529 len = serial_len; 3530 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) { 3531 old_length = le16_to_cpu(udev->config[index].desc.wTotalLength); 3532 len = max(len, old_length); 3533 } 3534 3535 buf = kmalloc(len, GFP_NOIO); 3536 if (buf == NULL) { 3537 dev_err(&udev->dev, "no mem to re-read configs after reset\n"); 3538 /* assume the worst */ 3539 return 1; 3540 } 3541 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) { 3542 old_length = le16_to_cpu(udev->config[index].desc.wTotalLength); 3543 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf, 3544 old_length); 3545 if (length != old_length) { 3546 dev_dbg(&udev->dev, "config index %d, error %d\n", 3547 index, length); 3548 changed = 1; 3549 break; 3550 } 3551 if (memcmp (buf, udev->rawdescriptors[index], old_length) 3552 != 0) { 3553 dev_dbg(&udev->dev, "config index %d changed (#%d)\n", 3554 index, 3555 ((struct usb_config_descriptor *) buf)-> 3556 bConfigurationValue); 3557 changed = 1; 3558 break; 3559 } 3560 } 3561 3562 if (!changed && serial_len) { 3563 length = usb_string(udev, udev->descriptor.iSerialNumber, 3564 buf, serial_len); 3565 if (length + 1 != serial_len) { 3566 dev_dbg(&udev->dev, "serial string error %d\n", 3567 length); 3568 changed = 1; 3569 } else if (memcmp(buf, udev->serial, length) != 0) { 3570 dev_dbg(&udev->dev, "serial string changed\n"); 3571 changed = 1; 3572 } 3573 } 3574 3575 kfree(buf); 3576 return changed; 3577 } 3578 3579 /** 3580 * usb_reset_and_verify_device - perform a USB port reset to reinitialize a device 3581 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state) 3582 * 3583 * WARNING - don't use this routine to reset a composite device 3584 * (one with multiple interfaces owned by separate drivers)! 3585 * Use usb_reset_device() instead. 3586 * 3587 * Do a port reset, reassign the device's address, and establish its 3588 * former operating configuration. If the reset fails, or the device's 3589 * descriptors change from their values before the reset, or the original 3590 * configuration and altsettings cannot be restored, a flag will be set 3591 * telling khubd to pretend the device has been disconnected and then 3592 * re-connected. All drivers will be unbound, and the device will be 3593 * re-enumerated and probed all over again. 3594 * 3595 * Returns 0 if the reset succeeded, -ENODEV if the device has been 3596 * flagged for logical disconnection, or some other negative error code 3597 * if the reset wasn't even attempted. 3598 * 3599 * The caller must own the device lock. For example, it's safe to use 3600 * this from a driver probe() routine after downloading new firmware. 3601 * For calls that might not occur during probe(), drivers should lock 3602 * the device using usb_lock_device_for_reset(). 3603 * 3604 * Locking exception: This routine may also be called from within an 3605 * autoresume handler. Such usage won't conflict with other tasks 3606 * holding the device lock because these tasks should always call 3607 * usb_autopm_resume_device(), thereby preventing any unwanted autoresume. 3608 */ 3609 static int usb_reset_and_verify_device(struct usb_device *udev) 3610 { 3611 struct usb_device *parent_hdev = udev->parent; 3612 struct usb_hub *parent_hub; 3613 struct usb_hcd *hcd = bus_to_hcd(udev->bus); 3614 struct usb_device_descriptor descriptor = udev->descriptor; 3615 int i, ret = 0; 3616 int port1 = udev->portnum; 3617 3618 if (udev->state == USB_STATE_NOTATTACHED || 3619 udev->state == USB_STATE_SUSPENDED) { 3620 dev_dbg(&udev->dev, "device reset not allowed in state %d\n", 3621 udev->state); 3622 return -EINVAL; 3623 } 3624 3625 if (!parent_hdev) { 3626 /* this requires hcd-specific logic; see OHCI hc_restart() */ 3627 dev_dbg(&udev->dev, "%s for root hub!\n", __func__); 3628 return -EISDIR; 3629 } 3630 parent_hub = hdev_to_hub(parent_hdev); 3631 3632 set_bit(port1, parent_hub->busy_bits); 3633 for (i = 0; i < SET_CONFIG_TRIES; ++i) { 3634 3635 /* ep0 maxpacket size may change; let the HCD know about it. 3636 * Other endpoints will be handled by re-enumeration. */ 3637 usb_ep0_reinit(udev); 3638 ret = hub_port_init(parent_hub, udev, port1, i); 3639 if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV) 3640 break; 3641 } 3642 clear_bit(port1, parent_hub->busy_bits); 3643 3644 if (ret < 0) 3645 goto re_enumerate; 3646 3647 /* Device might have changed firmware (DFU or similar) */ 3648 if (descriptors_changed(udev, &descriptor)) { 3649 dev_info(&udev->dev, "device firmware changed\n"); 3650 udev->descriptor = descriptor; /* for disconnect() calls */ 3651 goto re_enumerate; 3652 } 3653 3654 /* Restore the device's previous configuration */ 3655 if (!udev->actconfig) 3656 goto done; 3657 3658 mutex_lock(&hcd->bandwidth_mutex); 3659 ret = usb_hcd_alloc_bandwidth(udev, udev->actconfig, NULL, NULL); 3660 if (ret < 0) { 3661 dev_warn(&udev->dev, 3662 "Busted HC? Not enough HCD resources for " 3663 "old configuration.\n"); 3664 mutex_unlock(&hcd->bandwidth_mutex); 3665 goto re_enumerate; 3666 } 3667 ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0), 3668 USB_REQ_SET_CONFIGURATION, 0, 3669 udev->actconfig->desc.bConfigurationValue, 0, 3670 NULL, 0, USB_CTRL_SET_TIMEOUT); 3671 if (ret < 0) { 3672 dev_err(&udev->dev, 3673 "can't restore configuration #%d (error=%d)\n", 3674 udev->actconfig->desc.bConfigurationValue, ret); 3675 mutex_unlock(&hcd->bandwidth_mutex); 3676 goto re_enumerate; 3677 } 3678 mutex_unlock(&hcd->bandwidth_mutex); 3679 usb_set_device_state(udev, USB_STATE_CONFIGURED); 3680 3681 /* Put interfaces back into the same altsettings as before. 3682 * Don't bother to send the Set-Interface request for interfaces 3683 * that were already in altsetting 0; besides being unnecessary, 3684 * many devices can't handle it. Instead just reset the host-side 3685 * endpoint state. 3686 */ 3687 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) { 3688 struct usb_host_config *config = udev->actconfig; 3689 struct usb_interface *intf = config->interface[i]; 3690 struct usb_interface_descriptor *desc; 3691 3692 desc = &intf->cur_altsetting->desc; 3693 if (desc->bAlternateSetting == 0) { 3694 usb_disable_interface(udev, intf, true); 3695 usb_enable_interface(udev, intf, true); 3696 ret = 0; 3697 } else { 3698 /* Let the bandwidth allocation function know that this 3699 * device has been reset, and it will have to use 3700 * alternate setting 0 as the current alternate setting. 3701 */ 3702 intf->resetting_device = 1; 3703 ret = usb_set_interface(udev, desc->bInterfaceNumber, 3704 desc->bAlternateSetting); 3705 intf->resetting_device = 0; 3706 } 3707 if (ret < 0) { 3708 dev_err(&udev->dev, "failed to restore interface %d " 3709 "altsetting %d (error=%d)\n", 3710 desc->bInterfaceNumber, 3711 desc->bAlternateSetting, 3712 ret); 3713 goto re_enumerate; 3714 } 3715 } 3716 3717 done: 3718 return 0; 3719 3720 re_enumerate: 3721 hub_port_logical_disconnect(parent_hub, port1); 3722 return -ENODEV; 3723 } 3724 3725 /** 3726 * usb_reset_device - warn interface drivers and perform a USB port reset 3727 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state) 3728 * 3729 * Warns all drivers bound to registered interfaces (using their pre_reset 3730 * method), performs the port reset, and then lets the drivers know that 3731 * the reset is over (using their post_reset method). 3732 * 3733 * Return value is the same as for usb_reset_and_verify_device(). 3734 * 3735 * The caller must own the device lock. For example, it's safe to use 3736 * this from a driver probe() routine after downloading new firmware. 3737 * For calls that might not occur during probe(), drivers should lock 3738 * the device using usb_lock_device_for_reset(). 3739 * 3740 * If an interface is currently being probed or disconnected, we assume 3741 * its driver knows how to handle resets. For all other interfaces, 3742 * if the driver doesn't have pre_reset and post_reset methods then 3743 * we attempt to unbind it and rebind afterward. 3744 */ 3745 int usb_reset_device(struct usb_device *udev) 3746 { 3747 int ret; 3748 int i; 3749 struct usb_host_config *config = udev->actconfig; 3750 3751 if (udev->state == USB_STATE_NOTATTACHED || 3752 udev->state == USB_STATE_SUSPENDED) { 3753 dev_dbg(&udev->dev, "device reset not allowed in state %d\n", 3754 udev->state); 3755 return -EINVAL; 3756 } 3757 3758 /* Prevent autosuspend during the reset */ 3759 usb_autoresume_device(udev); 3760 3761 if (config) { 3762 for (i = 0; i < config->desc.bNumInterfaces; ++i) { 3763 struct usb_interface *cintf = config->interface[i]; 3764 struct usb_driver *drv; 3765 int unbind = 0; 3766 3767 if (cintf->dev.driver) { 3768 drv = to_usb_driver(cintf->dev.driver); 3769 if (drv->pre_reset && drv->post_reset) 3770 unbind = (drv->pre_reset)(cintf); 3771 else if (cintf->condition == 3772 USB_INTERFACE_BOUND) 3773 unbind = 1; 3774 if (unbind) 3775 usb_forced_unbind_intf(cintf); 3776 } 3777 } 3778 } 3779 3780 ret = usb_reset_and_verify_device(udev); 3781 3782 if (config) { 3783 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) { 3784 struct usb_interface *cintf = config->interface[i]; 3785 struct usb_driver *drv; 3786 int rebind = cintf->needs_binding; 3787 3788 if (!rebind && cintf->dev.driver) { 3789 drv = to_usb_driver(cintf->dev.driver); 3790 if (drv->post_reset) 3791 rebind = (drv->post_reset)(cintf); 3792 else if (cintf->condition == 3793 USB_INTERFACE_BOUND) 3794 rebind = 1; 3795 } 3796 if (ret == 0 && rebind) 3797 usb_rebind_intf(cintf); 3798 } 3799 } 3800 3801 usb_autosuspend_device(udev); 3802 return ret; 3803 } 3804 EXPORT_SYMBOL_GPL(usb_reset_device); 3805 3806 3807 /** 3808 * usb_queue_reset_device - Reset a USB device from an atomic context 3809 * @iface: USB interface belonging to the device to reset 3810 * 3811 * This function can be used to reset a USB device from an atomic 3812 * context, where usb_reset_device() won't work (as it blocks). 3813 * 3814 * Doing a reset via this method is functionally equivalent to calling 3815 * usb_reset_device(), except for the fact that it is delayed to a 3816 * workqueue. This means that any drivers bound to other interfaces 3817 * might be unbound, as well as users from usbfs in user space. 3818 * 3819 * Corner cases: 3820 * 3821 * - Scheduling two resets at the same time from two different drivers 3822 * attached to two different interfaces of the same device is 3823 * possible; depending on how the driver attached to each interface 3824 * handles ->pre_reset(), the second reset might happen or not. 3825 * 3826 * - If a driver is unbound and it had a pending reset, the reset will 3827 * be cancelled. 3828 * 3829 * - This function can be called during .probe() or .disconnect() 3830 * times. On return from .disconnect(), any pending resets will be 3831 * cancelled. 3832 * 3833 * There is no no need to lock/unlock the @reset_ws as schedule_work() 3834 * does its own. 3835 * 3836 * NOTE: We don't do any reference count tracking because it is not 3837 * needed. The lifecycle of the work_struct is tied to the 3838 * usb_interface. Before destroying the interface we cancel the 3839 * work_struct, so the fact that work_struct is queued and or 3840 * running means the interface (and thus, the device) exist and 3841 * are referenced. 3842 */ 3843 void usb_queue_reset_device(struct usb_interface *iface) 3844 { 3845 schedule_work(&iface->reset_ws); 3846 } 3847 EXPORT_SYMBOL_GPL(usb_queue_reset_device); 3848