USB: make hub driver's release more robust
[linux-2.6/verdex.git] / drivers / usb / core / hub.c
blob77a6627b18d2da8e4422e5cdf241dab85939e937
1 /*
2 * USB hub driver.
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)
9 */
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>
26 #include <asm/semaphore.h>
27 #include <asm/uaccess.h>
28 #include <asm/byteorder.h>
30 #include "usb.h"
31 #include "hcd.h"
32 #include "hub.h"
34 struct usb_hub {
35 struct device *intfdev; /* the "interface" device */
36 struct usb_device *hdev;
37 struct kref kref;
38 struct urb *urb; /* for interrupt polling pipe */
40 /* buffer for urb ... with extra space in case of babble */
41 char (*buffer)[8];
42 dma_addr_t buffer_dma; /* DMA address for buffer */
43 union {
44 struct usb_hub_status hub;
45 struct usb_port_status port;
46 } *status; /* buffer for status reports */
47 struct mutex status_mutex; /* for the status buffer */
49 int error; /* last reported error */
50 int nerrors; /* track consecutive errors */
52 struct list_head event_list; /* hubs w/data or errs ready */
53 unsigned long event_bits[1]; /* status change bitmask */
54 unsigned long change_bits[1]; /* ports with logical connect
55 status change */
56 unsigned long busy_bits[1]; /* ports being reset or
57 resumed */
58 #if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
59 #error event_bits[] is too short!
60 #endif
62 struct usb_hub_descriptor *descriptor; /* class descriptor */
63 struct usb_tt tt; /* Transaction Translator */
65 unsigned mA_per_port; /* current for each child */
67 unsigned limited_power:1;
68 unsigned quiescing:1;
69 unsigned activating:1;
70 unsigned disconnected:1;
72 unsigned has_indicators:1;
73 u8 indicator[USB_MAXCHILDREN];
74 struct delayed_work leds;
78 /* Protect struct usb_device->state and ->children members
79 * Note: Both are also protected by ->dev.sem, except that ->state can
80 * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
81 static DEFINE_SPINLOCK(device_state_lock);
83 /* khubd's worklist and its lock */
84 static DEFINE_SPINLOCK(hub_event_lock);
85 static LIST_HEAD(hub_event_list); /* List of hubs needing servicing */
87 /* Wakes up khubd */
88 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
90 static struct task_struct *khubd_task;
92 /* cycle leds on hubs that aren't blinking for attention */
93 static int blinkenlights = 0;
94 module_param (blinkenlights, bool, S_IRUGO);
95 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
98 * As of 2.6.10 we introduce a new USB device initialization scheme which
99 * closely resembles the way Windows works. Hopefully it will be compatible
100 * with a wider range of devices than the old scheme. However some previously
101 * working devices may start giving rise to "device not accepting address"
102 * errors; if that happens the user can try the old scheme by adjusting the
103 * following module parameters.
105 * For maximum flexibility there are two boolean parameters to control the
106 * hub driver's behavior. On the first initialization attempt, if the
107 * "old_scheme_first" parameter is set then the old scheme will be used,
108 * otherwise the new scheme is used. If that fails and "use_both_schemes"
109 * is set, then the driver will make another attempt, using the other scheme.
111 static int old_scheme_first = 0;
112 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
113 MODULE_PARM_DESC(old_scheme_first,
114 "start with the old device initialization scheme");
116 static int use_both_schemes = 1;
117 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
118 MODULE_PARM_DESC(use_both_schemes,
119 "try the other device initialization scheme if the "
120 "first one fails");
123 static inline char *portspeed(int portstatus)
125 if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
126 return "480 Mb/s";
127 else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
128 return "1.5 Mb/s";
129 else
130 return "12 Mb/s";
133 /* Note that hdev or one of its children must be locked! */
134 static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
136 return usb_get_intfdata(hdev->actconfig->interface[0]);
139 /* USB 2.0 spec Section 11.24.4.5 */
140 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
142 int i, ret;
144 for (i = 0; i < 3; i++) {
145 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
146 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
147 USB_DT_HUB << 8, 0, data, size,
148 USB_CTRL_GET_TIMEOUT);
149 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
150 return ret;
152 return -EINVAL;
156 * USB 2.0 spec Section 11.24.2.1
158 static int clear_hub_feature(struct usb_device *hdev, int feature)
160 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
161 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
165 * USB 2.0 spec Section 11.24.2.2
167 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
169 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
170 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
171 NULL, 0, 1000);
175 * USB 2.0 spec Section 11.24.2.13
177 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
179 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
180 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
181 NULL, 0, 1000);
185 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
186 * for info about using port indicators
188 static void set_port_led(
189 struct usb_hub *hub,
190 int port1,
191 int selector
194 int status = set_port_feature(hub->hdev, (selector << 8) | port1,
195 USB_PORT_FEAT_INDICATOR);
196 if (status < 0)
197 dev_dbg (hub->intfdev,
198 "port %d indicator %s status %d\n",
199 port1,
200 ({ char *s; switch (selector) {
201 case HUB_LED_AMBER: s = "amber"; break;
202 case HUB_LED_GREEN: s = "green"; break;
203 case HUB_LED_OFF: s = "off"; break;
204 case HUB_LED_AUTO: s = "auto"; break;
205 default: s = "??"; break;
206 }; s; }),
207 status);
210 #define LED_CYCLE_PERIOD ((2*HZ)/3)
212 static void led_work (struct work_struct *work)
214 struct usb_hub *hub =
215 container_of(work, struct usb_hub, leds.work);
216 struct usb_device *hdev = hub->hdev;
217 unsigned i;
218 unsigned changed = 0;
219 int cursor = -1;
221 if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
222 return;
224 for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
225 unsigned selector, mode;
227 /* 30%-50% duty cycle */
229 switch (hub->indicator[i]) {
230 /* cycle marker */
231 case INDICATOR_CYCLE:
232 cursor = i;
233 selector = HUB_LED_AUTO;
234 mode = INDICATOR_AUTO;
235 break;
236 /* blinking green = sw attention */
237 case INDICATOR_GREEN_BLINK:
238 selector = HUB_LED_GREEN;
239 mode = INDICATOR_GREEN_BLINK_OFF;
240 break;
241 case INDICATOR_GREEN_BLINK_OFF:
242 selector = HUB_LED_OFF;
243 mode = INDICATOR_GREEN_BLINK;
244 break;
245 /* blinking amber = hw attention */
246 case INDICATOR_AMBER_BLINK:
247 selector = HUB_LED_AMBER;
248 mode = INDICATOR_AMBER_BLINK_OFF;
249 break;
250 case INDICATOR_AMBER_BLINK_OFF:
251 selector = HUB_LED_OFF;
252 mode = INDICATOR_AMBER_BLINK;
253 break;
254 /* blink green/amber = reserved */
255 case INDICATOR_ALT_BLINK:
256 selector = HUB_LED_GREEN;
257 mode = INDICATOR_ALT_BLINK_OFF;
258 break;
259 case INDICATOR_ALT_BLINK_OFF:
260 selector = HUB_LED_AMBER;
261 mode = INDICATOR_ALT_BLINK;
262 break;
263 default:
264 continue;
266 if (selector != HUB_LED_AUTO)
267 changed = 1;
268 set_port_led(hub, i + 1, selector);
269 hub->indicator[i] = mode;
271 if (!changed && blinkenlights) {
272 cursor++;
273 cursor %= hub->descriptor->bNbrPorts;
274 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
275 hub->indicator[cursor] = INDICATOR_CYCLE;
276 changed++;
278 if (changed)
279 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
282 /* use a short timeout for hub/port status fetches */
283 #define USB_STS_TIMEOUT 1000
284 #define USB_STS_RETRIES 5
287 * USB 2.0 spec Section 11.24.2.6
289 static int get_hub_status(struct usb_device *hdev,
290 struct usb_hub_status *data)
292 int i, status = -ETIMEDOUT;
294 for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
295 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
296 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
297 data, sizeof(*data), USB_STS_TIMEOUT);
299 return status;
303 * USB 2.0 spec Section 11.24.2.7
305 static int get_port_status(struct usb_device *hdev, int port1,
306 struct usb_port_status *data)
308 int i, status = -ETIMEDOUT;
310 for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
311 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
312 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
313 data, sizeof(*data), USB_STS_TIMEOUT);
315 return status;
318 static void kick_khubd(struct usb_hub *hub)
320 unsigned long flags;
322 /* Suppress autosuspend until khubd runs */
323 to_usb_interface(hub->intfdev)->pm_usage_cnt = 1;
325 spin_lock_irqsave(&hub_event_lock, flags);
326 if (!hub->disconnected & list_empty(&hub->event_list)) {
327 list_add_tail(&hub->event_list, &hub_event_list);
328 wake_up(&khubd_wait);
330 spin_unlock_irqrestore(&hub_event_lock, flags);
333 void usb_kick_khubd(struct usb_device *hdev)
335 /* FIXME: What if hdev isn't bound to the hub driver? */
336 kick_khubd(hdev_to_hub(hdev));
340 /* completion function, fires on port status changes and various faults */
341 static void hub_irq(struct urb *urb)
343 struct usb_hub *hub = urb->context;
344 int status;
345 int i;
346 unsigned long bits;
348 switch (urb->status) {
349 case -ENOENT: /* synchronous unlink */
350 case -ECONNRESET: /* async unlink */
351 case -ESHUTDOWN: /* hardware going away */
352 return;
354 default: /* presumably an error */
355 /* Cause a hub reset after 10 consecutive errors */
356 dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
357 if ((++hub->nerrors < 10) || hub->error)
358 goto resubmit;
359 hub->error = urb->status;
360 /* FALL THROUGH */
362 /* let khubd handle things */
363 case 0: /* we got data: port status changed */
364 bits = 0;
365 for (i = 0; i < urb->actual_length; ++i)
366 bits |= ((unsigned long) ((*hub->buffer)[i]))
367 << (i*8);
368 hub->event_bits[0] = bits;
369 break;
372 hub->nerrors = 0;
374 /* Something happened, let khubd figure it out */
375 kick_khubd(hub);
377 resubmit:
378 if (hub->quiescing)
379 return;
381 if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
382 && status != -ENODEV && status != -EPERM)
383 dev_err (hub->intfdev, "resubmit --> %d\n", status);
386 /* USB 2.0 spec Section 11.24.2.3 */
387 static inline int
388 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
390 return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
391 HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
392 tt, NULL, 0, 1000);
396 * enumeration blocks khubd for a long time. we use keventd instead, since
397 * long blocking there is the exception, not the rule. accordingly, HCDs
398 * talking to TTs must queue control transfers (not just bulk and iso), so
399 * both can talk to the same hub concurrently.
401 static void hub_tt_kevent (struct work_struct *work)
403 struct usb_hub *hub =
404 container_of(work, struct usb_hub, tt.kevent);
405 unsigned long flags;
407 spin_lock_irqsave (&hub->tt.lock, flags);
408 while (!list_empty (&hub->tt.clear_list)) {
409 struct list_head *temp;
410 struct usb_tt_clear *clear;
411 struct usb_device *hdev = hub->hdev;
412 int status;
414 temp = hub->tt.clear_list.next;
415 clear = list_entry (temp, struct usb_tt_clear, clear_list);
416 list_del (&clear->clear_list);
418 /* drop lock so HCD can concurrently report other TT errors */
419 spin_unlock_irqrestore (&hub->tt.lock, flags);
420 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
421 spin_lock_irqsave (&hub->tt.lock, flags);
423 if (status)
424 dev_err (&hdev->dev,
425 "clear tt %d (%04x) error %d\n",
426 clear->tt, clear->devinfo, status);
427 kfree(clear);
429 spin_unlock_irqrestore (&hub->tt.lock, flags);
433 * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
434 * @udev: the device whose split transaction failed
435 * @pipe: identifies the endpoint of the failed transaction
437 * High speed HCDs use this to tell the hub driver that some split control or
438 * bulk transaction failed in a way that requires clearing internal state of
439 * a transaction translator. This is normally detected (and reported) from
440 * interrupt context.
442 * It may not be possible for that hub to handle additional full (or low)
443 * speed transactions until that state is fully cleared out.
445 void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
447 struct usb_tt *tt = udev->tt;
448 unsigned long flags;
449 struct usb_tt_clear *clear;
451 /* we've got to cope with an arbitrary number of pending TT clears,
452 * since each TT has "at least two" buffers that can need it (and
453 * there can be many TTs per hub). even if they're uncommon.
455 if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) {
456 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
457 /* FIXME recover somehow ... RESET_TT? */
458 return;
461 /* info that CLEAR_TT_BUFFER needs */
462 clear->tt = tt->multi ? udev->ttport : 1;
463 clear->devinfo = usb_pipeendpoint (pipe);
464 clear->devinfo |= udev->devnum << 4;
465 clear->devinfo |= usb_pipecontrol (pipe)
466 ? (USB_ENDPOINT_XFER_CONTROL << 11)
467 : (USB_ENDPOINT_XFER_BULK << 11);
468 if (usb_pipein (pipe))
469 clear->devinfo |= 1 << 15;
471 /* tell keventd to clear state for this TT */
472 spin_lock_irqsave (&tt->lock, flags);
473 list_add_tail (&clear->clear_list, &tt->clear_list);
474 schedule_work (&tt->kevent);
475 spin_unlock_irqrestore (&tt->lock, flags);
478 static void hub_power_on(struct usb_hub *hub)
480 int port1;
481 unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
482 u16 wHubCharacteristics =
483 le16_to_cpu(hub->descriptor->wHubCharacteristics);
485 /* Enable power on each port. Some hubs have reserved values
486 * of LPSM (> 2) in their descriptors, even though they are
487 * USB 2.0 hubs. Some hubs do not implement port-power switching
488 * but only emulate it. In all cases, the ports won't work
489 * unless we send these messages to the hub.
491 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
492 dev_dbg(hub->intfdev, "enabling power on all ports\n");
493 else
494 dev_dbg(hub->intfdev, "trying to enable port power on "
495 "non-switchable hub\n");
496 for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
497 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
499 /* Wait at least 100 msec for power to become stable */
500 msleep(max(pgood_delay, (unsigned) 100));
503 static void hub_quiesce(struct usb_hub *hub)
505 /* (nonblocking) khubd and related activity won't re-trigger */
506 hub->quiescing = 1;
507 hub->activating = 0;
509 /* (blocking) stop khubd and related activity */
510 usb_kill_urb(hub->urb);
511 if (hub->has_indicators)
512 cancel_delayed_work(&hub->leds);
513 if (hub->has_indicators || hub->tt.hub)
514 flush_scheduled_work();
517 static void hub_activate(struct usb_hub *hub)
519 int status;
521 hub->quiescing = 0;
522 hub->activating = 1;
524 status = usb_submit_urb(hub->urb, GFP_NOIO);
525 if (status < 0)
526 dev_err(hub->intfdev, "activate --> %d\n", status);
527 if (hub->has_indicators && blinkenlights)
528 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
530 /* scan all ports ASAP */
531 kick_khubd(hub);
534 static int hub_hub_status(struct usb_hub *hub,
535 u16 *status, u16 *change)
537 int ret;
539 mutex_lock(&hub->status_mutex);
540 ret = get_hub_status(hub->hdev, &hub->status->hub);
541 if (ret < 0)
542 dev_err (hub->intfdev,
543 "%s failed (err = %d)\n", __FUNCTION__, ret);
544 else {
545 *status = le16_to_cpu(hub->status->hub.wHubStatus);
546 *change = le16_to_cpu(hub->status->hub.wHubChange);
547 ret = 0;
549 mutex_unlock(&hub->status_mutex);
550 return ret;
553 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
555 struct usb_device *hdev = hub->hdev;
556 int ret;
558 if (hdev->children[port1-1] && set_state) {
559 usb_set_device_state(hdev->children[port1-1],
560 USB_STATE_NOTATTACHED);
562 ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
563 if (ret)
564 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
565 port1, ret);
567 return ret;
571 /* caller has locked the hub device */
572 static void hub_pre_reset(struct usb_interface *intf)
574 struct usb_hub *hub = usb_get_intfdata(intf);
575 struct usb_device *hdev = hub->hdev;
576 int port1;
578 for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
579 if (hdev->children[port1 - 1]) {
580 usb_disconnect(&hdev->children[port1 - 1]);
581 if (hub->error == 0)
582 hub_port_disable(hub, port1, 0);
585 hub_quiesce(hub);
588 /* caller has locked the hub device */
589 static void hub_post_reset(struct usb_interface *intf)
591 struct usb_hub *hub = usb_get_intfdata(intf);
593 hub_activate(hub);
594 hub_power_on(hub);
598 static int hub_configure(struct usb_hub *hub,
599 struct usb_endpoint_descriptor *endpoint)
601 struct usb_device *hdev = hub->hdev;
602 struct device *hub_dev = hub->intfdev;
603 u16 hubstatus, hubchange;
604 u16 wHubCharacteristics;
605 unsigned int pipe;
606 int maxp, ret;
607 char *message;
609 hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
610 &hub->buffer_dma);
611 if (!hub->buffer) {
612 message = "can't allocate hub irq buffer";
613 ret = -ENOMEM;
614 goto fail;
617 hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
618 if (!hub->status) {
619 message = "can't kmalloc hub status buffer";
620 ret = -ENOMEM;
621 goto fail;
623 mutex_init(&hub->status_mutex);
625 hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
626 if (!hub->descriptor) {
627 message = "can't kmalloc hub descriptor";
628 ret = -ENOMEM;
629 goto fail;
632 /* Request the entire hub descriptor.
633 * hub->descriptor can handle USB_MAXCHILDREN ports,
634 * but the hub can/will return fewer bytes here.
636 ret = get_hub_descriptor(hdev, hub->descriptor,
637 sizeof(*hub->descriptor));
638 if (ret < 0) {
639 message = "can't read hub descriptor";
640 goto fail;
641 } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
642 message = "hub has too many ports!";
643 ret = -ENODEV;
644 goto fail;
647 hdev->maxchild = hub->descriptor->bNbrPorts;
648 dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
649 (hdev->maxchild == 1) ? "" : "s");
651 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
653 if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
654 int i;
655 char portstr [USB_MAXCHILDREN + 1];
657 for (i = 0; i < hdev->maxchild; i++)
658 portstr[i] = hub->descriptor->DeviceRemovable
659 [((i + 1) / 8)] & (1 << ((i + 1) % 8))
660 ? 'F' : 'R';
661 portstr[hdev->maxchild] = 0;
662 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
663 } else
664 dev_dbg(hub_dev, "standalone hub\n");
666 switch (wHubCharacteristics & HUB_CHAR_LPSM) {
667 case 0x00:
668 dev_dbg(hub_dev, "ganged power switching\n");
669 break;
670 case 0x01:
671 dev_dbg(hub_dev, "individual port power switching\n");
672 break;
673 case 0x02:
674 case 0x03:
675 dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
676 break;
679 switch (wHubCharacteristics & HUB_CHAR_OCPM) {
680 case 0x00:
681 dev_dbg(hub_dev, "global over-current protection\n");
682 break;
683 case 0x08:
684 dev_dbg(hub_dev, "individual port over-current protection\n");
685 break;
686 case 0x10:
687 case 0x18:
688 dev_dbg(hub_dev, "no over-current protection\n");
689 break;
692 spin_lock_init (&hub->tt.lock);
693 INIT_LIST_HEAD (&hub->tt.clear_list);
694 INIT_WORK (&hub->tt.kevent, hub_tt_kevent);
695 switch (hdev->descriptor.bDeviceProtocol) {
696 case 0:
697 break;
698 case 1:
699 dev_dbg(hub_dev, "Single TT\n");
700 hub->tt.hub = hdev;
701 break;
702 case 2:
703 ret = usb_set_interface(hdev, 0, 1);
704 if (ret == 0) {
705 dev_dbg(hub_dev, "TT per port\n");
706 hub->tt.multi = 1;
707 } else
708 dev_err(hub_dev, "Using single TT (err %d)\n",
709 ret);
710 hub->tt.hub = hdev;
711 break;
712 default:
713 dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
714 hdev->descriptor.bDeviceProtocol);
715 break;
718 /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
719 switch (wHubCharacteristics & HUB_CHAR_TTTT) {
720 case HUB_TTTT_8_BITS:
721 if (hdev->descriptor.bDeviceProtocol != 0) {
722 hub->tt.think_time = 666;
723 dev_dbg(hub_dev, "TT requires at most %d "
724 "FS bit times (%d ns)\n",
725 8, hub->tt.think_time);
727 break;
728 case HUB_TTTT_16_BITS:
729 hub->tt.think_time = 666 * 2;
730 dev_dbg(hub_dev, "TT requires at most %d "
731 "FS bit times (%d ns)\n",
732 16, hub->tt.think_time);
733 break;
734 case HUB_TTTT_24_BITS:
735 hub->tt.think_time = 666 * 3;
736 dev_dbg(hub_dev, "TT requires at most %d "
737 "FS bit times (%d ns)\n",
738 24, hub->tt.think_time);
739 break;
740 case HUB_TTTT_32_BITS:
741 hub->tt.think_time = 666 * 4;
742 dev_dbg(hub_dev, "TT requires at most %d "
743 "FS bit times (%d ns)\n",
744 32, hub->tt.think_time);
745 break;
748 /* probe() zeroes hub->indicator[] */
749 if (wHubCharacteristics & HUB_CHAR_PORTIND) {
750 hub->has_indicators = 1;
751 dev_dbg(hub_dev, "Port indicators are supported\n");
754 dev_dbg(hub_dev, "power on to power good time: %dms\n",
755 hub->descriptor->bPwrOn2PwrGood * 2);
757 /* power budgeting mostly matters with bus-powered hubs,
758 * and battery-powered root hubs (may provide just 8 mA).
760 ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
761 if (ret < 2) {
762 message = "can't get hub status";
763 goto fail;
765 le16_to_cpus(&hubstatus);
766 if (hdev == hdev->bus->root_hub) {
767 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
768 hub->mA_per_port = 500;
769 else {
770 hub->mA_per_port = hdev->bus_mA;
771 hub->limited_power = 1;
773 } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
774 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
775 hub->descriptor->bHubContrCurrent);
776 hub->limited_power = 1;
777 if (hdev->maxchild > 0) {
778 int remaining = hdev->bus_mA -
779 hub->descriptor->bHubContrCurrent;
781 if (remaining < hdev->maxchild * 100)
782 dev_warn(hub_dev,
783 "insufficient power available "
784 "to use all downstream ports\n");
785 hub->mA_per_port = 100; /* 7.2.1.1 */
787 } else { /* Self-powered external hub */
788 /* FIXME: What about battery-powered external hubs that
789 * provide less current per port? */
790 hub->mA_per_port = 500;
792 if (hub->mA_per_port < 500)
793 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
794 hub->mA_per_port);
796 ret = hub_hub_status(hub, &hubstatus, &hubchange);
797 if (ret < 0) {
798 message = "can't get hub status";
799 goto fail;
802 /* local power status reports aren't always correct */
803 if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
804 dev_dbg(hub_dev, "local power source is %s\n",
805 (hubstatus & HUB_STATUS_LOCAL_POWER)
806 ? "lost (inactive)" : "good");
808 if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
809 dev_dbg(hub_dev, "%sover-current condition exists\n",
810 (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
812 /* set up the interrupt endpoint
813 * We use the EP's maxpacket size instead of (PORTS+1+7)/8
814 * bytes as USB2.0[11.12.3] says because some hubs are known
815 * to send more data (and thus cause overflow). For root hubs,
816 * maxpktsize is defined in hcd.c's fake endpoint descriptors
817 * to be big enough for at least USB_MAXCHILDREN ports. */
818 pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
819 maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
821 if (maxp > sizeof(*hub->buffer))
822 maxp = sizeof(*hub->buffer);
824 hub->urb = usb_alloc_urb(0, GFP_KERNEL);
825 if (!hub->urb) {
826 message = "couldn't allocate interrupt urb";
827 ret = -ENOMEM;
828 goto fail;
831 usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
832 hub, endpoint->bInterval);
833 hub->urb->transfer_dma = hub->buffer_dma;
834 hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
836 /* maybe cycle the hub leds */
837 if (hub->has_indicators && blinkenlights)
838 hub->indicator [0] = INDICATOR_CYCLE;
840 hub_power_on(hub);
841 hub_activate(hub);
842 return 0;
844 fail:
845 dev_err (hub_dev, "config failed, %s (err %d)\n",
846 message, ret);
847 /* hub_disconnect() frees urb and descriptor */
848 return ret;
851 static void hub_release(struct kref *kref)
853 struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
855 usb_put_intf(to_usb_interface(hub->intfdev));
856 kfree(hub);
859 static unsigned highspeed_hubs;
861 static void hub_disconnect(struct usb_interface *intf)
863 struct usb_hub *hub = usb_get_intfdata (intf);
865 /* Take the hub off the event list and don't let it be added again */
866 spin_lock_irq(&hub_event_lock);
867 list_del_init(&hub->event_list);
868 hub->disconnected = 1;
869 spin_unlock_irq(&hub_event_lock);
871 /* Disconnect all children and quiesce the hub */
872 hub->error = 0;
873 hub_pre_reset(intf);
875 usb_set_intfdata (intf, NULL);
877 if (hub->hdev->speed == USB_SPEED_HIGH)
878 highspeed_hubs--;
880 usb_free_urb(hub->urb);
881 kfree(hub->descriptor);
882 kfree(hub->status);
883 usb_buffer_free(hub->hdev, sizeof(*hub->buffer), hub->buffer,
884 hub->buffer_dma);
886 kref_put(&hub->kref, hub_release);
889 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
891 struct usb_host_interface *desc;
892 struct usb_endpoint_descriptor *endpoint;
893 struct usb_device *hdev;
894 struct usb_hub *hub;
896 desc = intf->cur_altsetting;
897 hdev = interface_to_usbdev(intf);
899 #ifdef CONFIG_USB_OTG_BLACKLIST_HUB
900 if (hdev->parent) {
901 dev_warn(&intf->dev, "ignoring external hub\n");
902 return -ENODEV;
904 #endif
906 /* Some hubs have a subclass of 1, which AFAICT according to the */
907 /* specs is not defined, but it works */
908 if ((desc->desc.bInterfaceSubClass != 0) &&
909 (desc->desc.bInterfaceSubClass != 1)) {
910 descriptor_error:
911 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
912 return -EIO;
915 /* Multiple endpoints? What kind of mutant ninja-hub is this? */
916 if (desc->desc.bNumEndpoints != 1)
917 goto descriptor_error;
919 endpoint = &desc->endpoint[0].desc;
921 /* If it's not an interrupt in endpoint, we'd better punt! */
922 if (!usb_endpoint_is_int_in(endpoint))
923 goto descriptor_error;
925 /* We found a hub */
926 dev_info (&intf->dev, "USB hub found\n");
928 hub = kzalloc(sizeof(*hub), GFP_KERNEL);
929 if (!hub) {
930 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
931 return -ENOMEM;
934 kref_init(&hub->kref);
935 INIT_LIST_HEAD(&hub->event_list);
936 hub->intfdev = &intf->dev;
937 hub->hdev = hdev;
938 INIT_DELAYED_WORK(&hub->leds, led_work);
939 usb_get_intf(intf);
941 usb_set_intfdata (intf, hub);
942 intf->needs_remote_wakeup = 1;
944 if (hdev->speed == USB_SPEED_HIGH)
945 highspeed_hubs++;
947 if (hub_configure(hub, endpoint) >= 0)
948 return 0;
950 hub_disconnect (intf);
951 return -ENODEV;
954 static int
955 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
957 struct usb_device *hdev = interface_to_usbdev (intf);
959 /* assert ifno == 0 (part of hub spec) */
960 switch (code) {
961 case USBDEVFS_HUB_PORTINFO: {
962 struct usbdevfs_hub_portinfo *info = user_data;
963 int i;
965 spin_lock_irq(&device_state_lock);
966 if (hdev->devnum <= 0)
967 info->nports = 0;
968 else {
969 info->nports = hdev->maxchild;
970 for (i = 0; i < info->nports; i++) {
971 if (hdev->children[i] == NULL)
972 info->port[i] = 0;
973 else
974 info->port[i] =
975 hdev->children[i]->devnum;
978 spin_unlock_irq(&device_state_lock);
980 return info->nports + 1;
983 default:
984 return -ENOSYS;
989 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
991 int i;
993 for (i = 0; i < udev->maxchild; ++i) {
994 if (udev->children[i])
995 recursively_mark_NOTATTACHED(udev->children[i]);
997 if (udev->state == USB_STATE_SUSPENDED)
998 udev->discon_suspended = 1;
999 udev->state = USB_STATE_NOTATTACHED;
1003 * usb_set_device_state - change a device's current state (usbcore, hcds)
1004 * @udev: pointer to device whose state should be changed
1005 * @new_state: new state value to be stored
1007 * udev->state is _not_ fully protected by the device lock. Although
1008 * most transitions are made only while holding the lock, the state can
1009 * can change to USB_STATE_NOTATTACHED at almost any time. This
1010 * is so that devices can be marked as disconnected as soon as possible,
1011 * without having to wait for any semaphores to be released. As a result,
1012 * all changes to any device's state must be protected by the
1013 * device_state_lock spinlock.
1015 * Once a device has been added to the device tree, all changes to its state
1016 * should be made using this routine. The state should _not_ be set directly.
1018 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1019 * Otherwise udev->state is set to new_state, and if new_state is
1020 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1021 * to USB_STATE_NOTATTACHED.
1023 void usb_set_device_state(struct usb_device *udev,
1024 enum usb_device_state new_state)
1026 unsigned long flags;
1028 spin_lock_irqsave(&device_state_lock, flags);
1029 if (udev->state == USB_STATE_NOTATTACHED)
1030 ; /* do nothing */
1031 else if (new_state != USB_STATE_NOTATTACHED) {
1033 /* root hub wakeup capabilities are managed out-of-band
1034 * and may involve silicon errata ... ignore them here.
1036 if (udev->parent) {
1037 if (udev->state == USB_STATE_SUSPENDED
1038 || new_state == USB_STATE_SUSPENDED)
1039 ; /* No change to wakeup settings */
1040 else if (new_state == USB_STATE_CONFIGURED)
1041 device_init_wakeup(&udev->dev,
1042 (udev->actconfig->desc.bmAttributes
1043 & USB_CONFIG_ATT_WAKEUP));
1044 else
1045 device_init_wakeup(&udev->dev, 0);
1047 udev->state = new_state;
1048 } else
1049 recursively_mark_NOTATTACHED(udev);
1050 spin_unlock_irqrestore(&device_state_lock, flags);
1054 #ifdef CONFIG_PM
1057 * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
1058 * @rhdev: struct usb_device for the root hub
1060 * The USB host controller driver calls this function when its root hub
1061 * is resumed and Vbus power has been interrupted or the controller
1062 * has been reset. The routine marks all the children of the root hub
1063 * as NOTATTACHED and marks logical connect-change events on their ports.
1065 void usb_root_hub_lost_power(struct usb_device *rhdev)
1067 struct usb_hub *hub;
1068 int port1;
1069 unsigned long flags;
1071 dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
1073 spin_lock_irqsave(&device_state_lock, flags);
1074 hub = hdev_to_hub(rhdev);
1075 for (port1 = 1; port1 <= rhdev->maxchild; ++port1) {
1076 if (rhdev->children[port1 - 1]) {
1077 recursively_mark_NOTATTACHED(
1078 rhdev->children[port1 - 1]);
1079 set_bit(port1, hub->change_bits);
1082 spin_unlock_irqrestore(&device_state_lock, flags);
1084 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
1086 #endif /* CONFIG_PM */
1088 static void choose_address(struct usb_device *udev)
1090 int devnum;
1091 struct usb_bus *bus = udev->bus;
1093 /* If khubd ever becomes multithreaded, this will need a lock */
1095 /* Try to allocate the next devnum beginning at bus->devnum_next. */
1096 devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1097 bus->devnum_next);
1098 if (devnum >= 128)
1099 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1101 bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1103 if (devnum < 128) {
1104 set_bit(devnum, bus->devmap.devicemap);
1105 udev->devnum = devnum;
1109 static void release_address(struct usb_device *udev)
1111 if (udev->devnum > 0) {
1112 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1113 udev->devnum = -1;
1117 #ifdef CONFIG_USB_SUSPEND
1119 static void usb_stop_pm(struct usb_device *udev)
1121 /* Synchronize with the ksuspend thread to prevent any more
1122 * autosuspend requests from being submitted, and decrement
1123 * the parent's count of unsuspended children.
1125 usb_pm_lock(udev);
1126 if (udev->parent && !udev->discon_suspended)
1127 usb_autosuspend_device(udev->parent);
1128 usb_pm_unlock(udev);
1130 /* Stop any autosuspend requests already submitted */
1131 cancel_rearming_delayed_work(&udev->autosuspend);
1134 #else
1136 static inline void usb_stop_pm(struct usb_device *udev)
1139 #endif
1142 * usb_disconnect - disconnect a device (usbcore-internal)
1143 * @pdev: pointer to device being disconnected
1144 * Context: !in_interrupt ()
1146 * Something got disconnected. Get rid of it and all of its children.
1148 * If *pdev is a normal device then the parent hub must already be locked.
1149 * If *pdev is a root hub then this routine will acquire the
1150 * usb_bus_list_lock on behalf of the caller.
1152 * Only hub drivers (including virtual root hub drivers for host
1153 * controllers) should ever call this.
1155 * This call is synchronous, and may not be used in an interrupt context.
1157 void usb_disconnect(struct usb_device **pdev)
1159 struct usb_device *udev = *pdev;
1160 int i;
1162 if (!udev) {
1163 pr_debug ("%s nodev\n", __FUNCTION__);
1164 return;
1167 /* mark the device as inactive, so any further urb submissions for
1168 * this device (and any of its children) will fail immediately.
1169 * this quiesces everyting except pending urbs.
1171 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1172 dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1174 usb_lock_device(udev);
1176 /* Free up all the children before we remove this device */
1177 for (i = 0; i < USB_MAXCHILDREN; i++) {
1178 if (udev->children[i])
1179 usb_disconnect(&udev->children[i]);
1182 /* deallocate hcd/hardware state ... nuking all pending urbs and
1183 * cleaning up all state associated with the current configuration
1184 * so that the hardware is now fully quiesced.
1186 dev_dbg (&udev->dev, "unregistering device\n");
1187 usb_disable_device(udev, 0);
1189 usb_unlock_device(udev);
1191 /* Unregister the device. The device driver is responsible
1192 * for removing the device files from usbfs and sysfs and for
1193 * de-configuring the device.
1195 device_del(&udev->dev);
1197 /* Free the device number and delete the parent's children[]
1198 * (or root_hub) pointer.
1200 release_address(udev);
1202 /* Avoid races with recursively_mark_NOTATTACHED() */
1203 spin_lock_irq(&device_state_lock);
1204 *pdev = NULL;
1205 spin_unlock_irq(&device_state_lock);
1207 usb_stop_pm(udev);
1209 put_device(&udev->dev);
1212 #ifdef DEBUG
1213 static void show_string(struct usb_device *udev, char *id, char *string)
1215 if (!string)
1216 return;
1217 dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1220 #else
1221 static inline void show_string(struct usb_device *udev, char *id, char *string)
1223 #endif
1226 #ifdef CONFIG_USB_OTG
1227 #include "otg_whitelist.h"
1228 static int __usb_port_suspend(struct usb_device *, int port1);
1229 #endif
1232 * usb_new_device - perform initial device setup (usbcore-internal)
1233 * @udev: newly addressed device (in ADDRESS state)
1235 * This is called with devices which have been enumerated, but not yet
1236 * configured. The device descriptor is available, but not descriptors
1237 * for any device configuration. The caller must have locked either
1238 * the parent hub (if udev is a normal device) or else the
1239 * usb_bus_list_lock (if udev is a root hub). The parent's pointer to
1240 * udev has already been installed, but udev is not yet visible through
1241 * sysfs or other filesystem code.
1243 * It will return if the device is configured properly or not. Zero if
1244 * the interface was registered with the driver core; else a negative
1245 * errno value.
1247 * This call is synchronous, and may not be used in an interrupt context.
1249 * Only the hub driver or root-hub registrar should ever call this.
1251 int usb_new_device(struct usb_device *udev)
1253 int err;
1255 /* Determine quirks */
1256 usb_detect_quirks(udev);
1258 err = usb_get_configuration(udev);
1259 if (err < 0) {
1260 dev_err(&udev->dev, "can't read configurations, error %d\n",
1261 err);
1262 goto fail;
1265 /* read the standard strings and cache them if present */
1266 udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1267 udev->manufacturer = usb_cache_string(udev,
1268 udev->descriptor.iManufacturer);
1269 udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1271 /* Tell the world! */
1272 dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1273 "SerialNumber=%d\n",
1274 udev->descriptor.iManufacturer,
1275 udev->descriptor.iProduct,
1276 udev->descriptor.iSerialNumber);
1277 show_string(udev, "Product", udev->product);
1278 show_string(udev, "Manufacturer", udev->manufacturer);
1279 show_string(udev, "SerialNumber", udev->serial);
1281 #ifdef CONFIG_USB_OTG
1283 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1284 * to wake us after we've powered off VBUS; and HNP, switching roles
1285 * "host" to "peripheral". The OTG descriptor helps figure this out.
1287 if (!udev->bus->is_b_host
1288 && udev->config
1289 && udev->parent == udev->bus->root_hub) {
1290 struct usb_otg_descriptor *desc = 0;
1291 struct usb_bus *bus = udev->bus;
1293 /* descriptor may appear anywhere in config */
1294 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1295 le16_to_cpu(udev->config[0].desc.wTotalLength),
1296 USB_DT_OTG, (void **) &desc) == 0) {
1297 if (desc->bmAttributes & USB_OTG_HNP) {
1298 unsigned port1 = udev->portnum;
1300 dev_info(&udev->dev,
1301 "Dual-Role OTG device on %sHNP port\n",
1302 (port1 == bus->otg_port)
1303 ? "" : "non-");
1305 /* enable HNP before suspend, it's simpler */
1306 if (port1 == bus->otg_port)
1307 bus->b_hnp_enable = 1;
1308 err = usb_control_msg(udev,
1309 usb_sndctrlpipe(udev, 0),
1310 USB_REQ_SET_FEATURE, 0,
1311 bus->b_hnp_enable
1312 ? USB_DEVICE_B_HNP_ENABLE
1313 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1314 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1315 if (err < 0) {
1316 /* OTG MESSAGE: report errors here,
1317 * customize to match your product.
1319 dev_info(&udev->dev,
1320 "can't set HNP mode; %d\n",
1321 err);
1322 bus->b_hnp_enable = 0;
1328 if (!is_targeted(udev)) {
1330 /* Maybe it can talk to us, though we can't talk to it.
1331 * (Includes HNP test device.)
1333 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1334 err = __usb_port_suspend(udev, udev->bus->otg_port);
1335 if (err < 0)
1336 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1338 err = -ENODEV;
1339 goto fail;
1341 #endif
1343 /* export the usbdev device-node for libusb */
1344 udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
1345 (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
1347 /* Register the device. The device driver is responsible
1348 * for adding the device files to sysfs and for configuring
1349 * the device.
1351 err = device_add(&udev->dev);
1352 if (err) {
1353 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1354 goto fail;
1357 /* Increment the parent's count of unsuspended children */
1358 if (udev->parent)
1359 usb_autoresume_device(udev->parent);
1361 exit:
1362 return err;
1364 fail:
1365 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1366 goto exit;
1369 static int hub_port_status(struct usb_hub *hub, int port1,
1370 u16 *status, u16 *change)
1372 int ret;
1374 mutex_lock(&hub->status_mutex);
1375 ret = get_port_status(hub->hdev, port1, &hub->status->port);
1376 if (ret < 4) {
1377 dev_err (hub->intfdev,
1378 "%s failed (err = %d)\n", __FUNCTION__, ret);
1379 if (ret >= 0)
1380 ret = -EIO;
1381 } else {
1382 *status = le16_to_cpu(hub->status->port.wPortStatus);
1383 *change = le16_to_cpu(hub->status->port.wPortChange);
1384 ret = 0;
1386 mutex_unlock(&hub->status_mutex);
1387 return ret;
1391 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
1392 static unsigned hub_is_wusb(struct usb_hub *hub)
1394 struct usb_hcd *hcd;
1395 if (hub->hdev->parent != NULL) /* not a root hub? */
1396 return 0;
1397 hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
1398 return hcd->wireless;
1402 #define PORT_RESET_TRIES 5
1403 #define SET_ADDRESS_TRIES 2
1404 #define GET_DESCRIPTOR_TRIES 2
1405 #define SET_CONFIG_TRIES (2 * (use_both_schemes + 1))
1406 #define USE_NEW_SCHEME(i) ((i) / 2 == old_scheme_first)
1408 #define HUB_ROOT_RESET_TIME 50 /* times are in msec */
1409 #define HUB_SHORT_RESET_TIME 10
1410 #define HUB_LONG_RESET_TIME 200
1411 #define HUB_RESET_TIMEOUT 500
1413 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1414 struct usb_device *udev, unsigned int delay)
1416 int delay_time, ret;
1417 u16 portstatus;
1418 u16 portchange;
1420 for (delay_time = 0;
1421 delay_time < HUB_RESET_TIMEOUT;
1422 delay_time += delay) {
1423 /* wait to give the device a chance to reset */
1424 msleep(delay);
1426 /* read and decode port status */
1427 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1428 if (ret < 0)
1429 return ret;
1431 /* Device went away? */
1432 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1433 return -ENOTCONN;
1435 /* bomb out completely if something weird happened */
1436 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1437 return -EINVAL;
1439 /* if we`ve finished resetting, then break out of the loop */
1440 if (!(portstatus & USB_PORT_STAT_RESET) &&
1441 (portstatus & USB_PORT_STAT_ENABLE)) {
1442 if (hub_is_wusb(hub))
1443 udev->speed = USB_SPEED_VARIABLE;
1444 else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1445 udev->speed = USB_SPEED_HIGH;
1446 else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1447 udev->speed = USB_SPEED_LOW;
1448 else
1449 udev->speed = USB_SPEED_FULL;
1450 return 0;
1453 /* switch to the long delay after two short delay failures */
1454 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1455 delay = HUB_LONG_RESET_TIME;
1457 dev_dbg (hub->intfdev,
1458 "port %d not reset yet, waiting %dms\n",
1459 port1, delay);
1462 return -EBUSY;
1465 static int hub_port_reset(struct usb_hub *hub, int port1,
1466 struct usb_device *udev, unsigned int delay)
1468 int i, status;
1470 /* Reset the port */
1471 for (i = 0; i < PORT_RESET_TRIES; i++) {
1472 status = set_port_feature(hub->hdev,
1473 port1, USB_PORT_FEAT_RESET);
1474 if (status)
1475 dev_err(hub->intfdev,
1476 "cannot reset port %d (err = %d)\n",
1477 port1, status);
1478 else {
1479 status = hub_port_wait_reset(hub, port1, udev, delay);
1480 if (status && status != -ENOTCONN)
1481 dev_dbg(hub->intfdev,
1482 "port_wait_reset: err = %d\n",
1483 status);
1486 /* return on disconnect or reset */
1487 switch (status) {
1488 case 0:
1489 /* TRSTRCY = 10 ms; plus some extra */
1490 msleep(10 + 40);
1491 /* FALL THROUGH */
1492 case -ENOTCONN:
1493 case -ENODEV:
1494 clear_port_feature(hub->hdev,
1495 port1, USB_PORT_FEAT_C_RESET);
1496 /* FIXME need disconnect() for NOTATTACHED device */
1497 usb_set_device_state(udev, status
1498 ? USB_STATE_NOTATTACHED
1499 : USB_STATE_DEFAULT);
1500 return status;
1503 dev_dbg (hub->intfdev,
1504 "port %d not enabled, trying reset again...\n",
1505 port1);
1506 delay = HUB_LONG_RESET_TIME;
1509 dev_err (hub->intfdev,
1510 "Cannot enable port %i. Maybe the USB cable is bad?\n",
1511 port1);
1513 return status;
1517 * Disable a port and mark a logical connnect-change event, so that some
1518 * time later khubd will disconnect() any existing usb_device on the port
1519 * and will re-enumerate if there actually is a device attached.
1521 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1523 dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1524 hub_port_disable(hub, port1, 1);
1526 /* FIXME let caller ask to power down the port:
1527 * - some devices won't enumerate without a VBUS power cycle
1528 * - SRP saves power that way
1529 * - ... new call, TBD ...
1530 * That's easy if this hub can switch power per-port, and
1531 * khubd reactivates the port later (timer, SRP, etc).
1532 * Powerdown must be optional, because of reset/DFU.
1535 set_bit(port1, hub->change_bits);
1536 kick_khubd(hub);
1539 #ifdef CONFIG_PM
1541 #ifdef CONFIG_USB_SUSPEND
1544 * Selective port suspend reduces power; most suspended devices draw
1545 * less than 500 uA. It's also used in OTG, along with remote wakeup.
1546 * All devices below the suspended port are also suspended.
1548 * Devices leave suspend state when the host wakes them up. Some devices
1549 * also support "remote wakeup", where the device can activate the USB
1550 * tree above them to deliver data, such as a keypress or packet. In
1551 * some cases, this wakes the USB host.
1553 static int hub_port_suspend(struct usb_hub *hub, int port1,
1554 struct usb_device *udev)
1556 int status;
1558 // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1560 /* enable remote wakeup when appropriate; this lets the device
1561 * wake up the upstream hub (including maybe the root hub).
1563 * NOTE: OTG devices may issue remote wakeup (or SRP) even when
1564 * we don't explicitly enable it here.
1566 if (udev->do_remote_wakeup) {
1567 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1568 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1569 USB_DEVICE_REMOTE_WAKEUP, 0,
1570 NULL, 0,
1571 USB_CTRL_SET_TIMEOUT);
1572 if (status)
1573 dev_dbg(&udev->dev,
1574 "won't remote wakeup, status %d\n",
1575 status);
1578 /* see 7.1.7.6 */
1579 status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1580 if (status) {
1581 dev_dbg(hub->intfdev,
1582 "can't suspend port %d, status %d\n",
1583 port1, status);
1584 /* paranoia: "should not happen" */
1585 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1586 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1587 USB_DEVICE_REMOTE_WAKEUP, 0,
1588 NULL, 0,
1589 USB_CTRL_SET_TIMEOUT);
1590 } else {
1591 /* device has up to 10 msec to fully suspend */
1592 dev_dbg(&udev->dev, "usb %ssuspend\n",
1593 udev->auto_pm ? "auto-" : "");
1594 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1595 msleep(10);
1597 return status;
1601 * Devices on USB hub ports have only one "suspend" state, corresponding
1602 * to ACPI D2, "may cause the device to lose some context".
1603 * State transitions include:
1605 * - suspend, resume ... when the VBUS power link stays live
1606 * - suspend, disconnect ... VBUS lost
1608 * Once VBUS drop breaks the circuit, the port it's using has to go through
1609 * normal re-enumeration procedures, starting with enabling VBUS power.
1610 * Other than re-initializing the hub (plug/unplug, except for root hubs),
1611 * Linux (2.6) currently has NO mechanisms to initiate that: no khubd
1612 * timer, no SRP, no requests through sysfs.
1614 * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1615 * the root hub for their bus goes into global suspend ... so we don't
1616 * (falsely) update the device power state to say it suspended.
1618 static int __usb_port_suspend (struct usb_device *udev, int port1)
1620 int status = 0;
1622 /* caller owns the udev device lock */
1623 if (port1 < 0)
1624 return port1;
1626 /* we change the device's upstream USB link,
1627 * but root hubs have no upstream USB link.
1629 if (udev->parent)
1630 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1631 udev);
1632 else {
1633 dev_dbg(&udev->dev, "usb %ssuspend\n",
1634 udev->auto_pm ? "auto-" : "");
1635 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1637 return status;
1641 * usb_port_suspend - suspend a usb device's upstream port
1642 * @udev: device that's no longer in active use
1643 * Context: must be able to sleep; device not locked; pm locks held
1645 * Suspends a USB device that isn't in active use, conserving power.
1646 * Devices may wake out of a suspend, if anything important happens,
1647 * using the remote wakeup mechanism. They may also be taken out of
1648 * suspend by the host, using usb_port_resume(). It's also routine
1649 * to disconnect devices while they are suspended.
1651 * This only affects the USB hardware for a device; its interfaces
1652 * (and, for hubs, child devices) must already have been suspended.
1654 * Suspending OTG devices may trigger HNP, if that's been enabled
1655 * between a pair of dual-role devices. That will change roles, such
1656 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1658 * Returns 0 on success, else negative errno.
1660 int usb_port_suspend(struct usb_device *udev)
1662 return __usb_port_suspend(udev, udev->portnum);
1666 * If the USB "suspend" state is in use (rather than "global suspend"),
1667 * many devices will be individually taken out of suspend state using
1668 * special" resume" signaling. These routines kick in shortly after
1669 * hardware resume signaling is finished, either because of selective
1670 * resume (by host) or remote wakeup (by device) ... now see what changed
1671 * in the tree that's rooted at this device.
1673 static int finish_port_resume(struct usb_device *udev)
1675 int status;
1676 u16 devstatus;
1678 /* caller owns the udev device lock */
1679 dev_dbg(&udev->dev, "finish resume\n");
1681 /* usb ch9 identifies four variants of SUSPENDED, based on what
1682 * state the device resumes to. Linux currently won't see the
1683 * first two on the host side; they'd be inside hub_port_init()
1684 * during many timeouts, but khubd can't suspend until later.
1686 usb_set_device_state(udev, udev->actconfig
1687 ? USB_STATE_CONFIGURED
1688 : USB_STATE_ADDRESS);
1690 /* 10.5.4.5 says be sure devices in the tree are still there.
1691 * For now let's assume the device didn't go crazy on resume,
1692 * and device drivers will know about any resume quirks.
1694 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1695 if (status >= 0)
1696 status = (status == 2 ? 0 : -ENODEV);
1698 if (status)
1699 dev_dbg(&udev->dev,
1700 "gone after usb resume? status %d\n",
1701 status);
1702 else if (udev->actconfig) {
1703 le16_to_cpus(&devstatus);
1704 if ((devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
1705 && udev->parent) {
1706 status = usb_control_msg(udev,
1707 usb_sndctrlpipe(udev, 0),
1708 USB_REQ_CLEAR_FEATURE,
1709 USB_RECIP_DEVICE,
1710 USB_DEVICE_REMOTE_WAKEUP, 0,
1711 NULL, 0,
1712 USB_CTRL_SET_TIMEOUT);
1713 if (status)
1714 dev_dbg(&udev->dev, "disable remote "
1715 "wakeup, status %d\n", status);
1717 status = 0;
1719 } else if (udev->devnum <= 0) {
1720 dev_dbg(&udev->dev, "bogus resume!\n");
1721 status = -EINVAL;
1723 return status;
1726 static int
1727 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1729 int status;
1730 u16 portchange, portstatus;
1732 /* Skip the initial Clear-Suspend step for a remote wakeup */
1733 status = hub_port_status(hub, port1, &portstatus, &portchange);
1734 if (status == 0 && !(portstatus & USB_PORT_STAT_SUSPEND))
1735 goto SuspendCleared;
1737 // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1739 set_bit(port1, hub->busy_bits);
1741 /* see 7.1.7.7; affects power usage, but not budgeting */
1742 status = clear_port_feature(hub->hdev,
1743 port1, USB_PORT_FEAT_SUSPEND);
1744 if (status) {
1745 dev_dbg(hub->intfdev,
1746 "can't resume port %d, status %d\n",
1747 port1, status);
1748 } else {
1749 /* drive resume for at least 20 msec */
1750 if (udev)
1751 dev_dbg(&udev->dev, "usb %sresume\n",
1752 udev->auto_pm ? "auto-" : "");
1753 msleep(25);
1755 #define LIVE_FLAGS ( USB_PORT_STAT_POWER \
1756 | USB_PORT_STAT_ENABLE \
1757 | USB_PORT_STAT_CONNECTION)
1759 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1760 * stop resume signaling. Then finish the resume
1761 * sequence.
1763 status = hub_port_status(hub, port1, &portstatus, &portchange);
1764 SuspendCleared:
1765 if (status < 0
1766 || (portstatus & LIVE_FLAGS) != LIVE_FLAGS
1767 || (portstatus & USB_PORT_STAT_SUSPEND) != 0
1769 dev_dbg(hub->intfdev,
1770 "port %d status %04x.%04x after resume, %d\n",
1771 port1, portchange, portstatus, status);
1772 if (status >= 0)
1773 status = -ENODEV;
1774 } else {
1775 if (portchange & USB_PORT_STAT_C_SUSPEND)
1776 clear_port_feature(hub->hdev, port1,
1777 USB_PORT_FEAT_C_SUSPEND);
1778 /* TRSMRCY = 10 msec */
1779 msleep(10);
1780 if (udev)
1781 status = finish_port_resume(udev);
1784 if (status < 0)
1785 hub_port_logical_disconnect(hub, port1);
1787 clear_bit(port1, hub->busy_bits);
1788 if (!hub->hdev->parent && !hub->busy_bits[0])
1789 usb_enable_root_hub_irq(hub->hdev->bus);
1791 return status;
1795 * usb_port_resume - re-activate a suspended usb device's upstream port
1796 * @udev: device to re-activate
1797 * Context: must be able to sleep; device not locked; pm locks held
1799 * This will re-activate the suspended device, increasing power usage
1800 * while letting drivers communicate again with its endpoints.
1801 * USB resume explicitly guarantees that the power session between
1802 * the host and the device is the same as it was when the device
1803 * suspended.
1805 * Returns 0 on success, else negative errno.
1807 int usb_port_resume(struct usb_device *udev)
1809 int status;
1811 /* we change the device's upstream USB link,
1812 * but root hubs have no upstream USB link.
1814 if (udev->parent) {
1815 // NOTE this fails if parent is also suspended...
1816 status = hub_port_resume(hdev_to_hub(udev->parent),
1817 udev->portnum, udev);
1818 } else {
1819 dev_dbg(&udev->dev, "usb %sresume\n",
1820 udev->auto_pm ? "auto-" : "");
1821 status = finish_port_resume(udev);
1823 if (status < 0)
1824 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
1825 return status;
1828 static int remote_wakeup(struct usb_device *udev)
1830 int status = 0;
1832 usb_lock_device(udev);
1833 if (udev->state == USB_STATE_SUSPENDED) {
1834 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
1835 usb_mark_last_busy(udev);
1836 status = usb_external_resume_device(udev);
1838 usb_unlock_device(udev);
1839 return status;
1842 #else /* CONFIG_USB_SUSPEND */
1844 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
1846 int usb_port_suspend(struct usb_device *udev)
1848 return 0;
1851 static inline int
1852 finish_port_resume(struct usb_device *udev)
1854 return 0;
1857 static inline int
1858 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1860 return 0;
1863 int usb_port_resume(struct usb_device *udev)
1865 return 0;
1868 static inline int remote_wakeup(struct usb_device *udev)
1870 return 0;
1873 #endif
1875 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
1877 struct usb_hub *hub = usb_get_intfdata (intf);
1878 struct usb_device *hdev = hub->hdev;
1879 unsigned port1;
1881 /* fail if children aren't already suspended */
1882 for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1883 struct usb_device *udev;
1885 udev = hdev->children [port1-1];
1886 if (udev && msg.event == PM_EVENT_SUSPEND &&
1887 #ifdef CONFIG_USB_SUSPEND
1888 udev->state != USB_STATE_SUSPENDED
1889 #else
1890 udev->dev.power.power_state.event
1891 == PM_EVENT_ON
1892 #endif
1894 if (!hdev->auto_pm)
1895 dev_dbg(&intf->dev, "port %d nyet suspended\n",
1896 port1);
1897 return -EBUSY;
1901 dev_dbg(&intf->dev, "%s\n", __FUNCTION__);
1903 /* stop khubd and related activity */
1904 hub_quiesce(hub);
1905 return 0;
1908 static int hub_resume(struct usb_interface *intf)
1910 struct usb_hub *hub = usb_get_intfdata (intf);
1912 dev_dbg(&intf->dev, "%s\n", __FUNCTION__);
1914 /* tell khubd to look for changes on this hub */
1915 hub_activate(hub);
1916 return 0;
1919 #else /* CONFIG_PM */
1921 static inline int remote_wakeup(struct usb_device *udev)
1923 return 0;
1926 #define hub_suspend NULL
1927 #define hub_resume NULL
1928 #endif
1931 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
1933 * Between connect detection and reset signaling there must be a delay
1934 * of 100ms at least for debounce and power-settling. The corresponding
1935 * timer shall restart whenever the downstream port detects a disconnect.
1937 * Apparently there are some bluetooth and irda-dongles and a number of
1938 * low-speed devices for which this debounce period may last over a second.
1939 * Not covered by the spec - but easy to deal with.
1941 * This implementation uses a 1500ms total debounce timeout; if the
1942 * connection isn't stable by then it returns -ETIMEDOUT. It checks
1943 * every 25ms for transient disconnects. When the port status has been
1944 * unchanged for 100ms it returns the port status.
1947 #define HUB_DEBOUNCE_TIMEOUT 1500
1948 #define HUB_DEBOUNCE_STEP 25
1949 #define HUB_DEBOUNCE_STABLE 100
1951 static int hub_port_debounce(struct usb_hub *hub, int port1)
1953 int ret;
1954 int total_time, stable_time = 0;
1955 u16 portchange, portstatus;
1956 unsigned connection = 0xffff;
1958 for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
1959 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1960 if (ret < 0)
1961 return ret;
1963 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
1964 (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
1965 stable_time += HUB_DEBOUNCE_STEP;
1966 if (stable_time >= HUB_DEBOUNCE_STABLE)
1967 break;
1968 } else {
1969 stable_time = 0;
1970 connection = portstatus & USB_PORT_STAT_CONNECTION;
1973 if (portchange & USB_PORT_STAT_C_CONNECTION) {
1974 clear_port_feature(hub->hdev, port1,
1975 USB_PORT_FEAT_C_CONNECTION);
1978 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
1979 break;
1980 msleep(HUB_DEBOUNCE_STEP);
1983 dev_dbg (hub->intfdev,
1984 "debounce: port %d: total %dms stable %dms status 0x%x\n",
1985 port1, total_time, stable_time, portstatus);
1987 if (stable_time < HUB_DEBOUNCE_STABLE)
1988 return -ETIMEDOUT;
1989 return portstatus;
1992 static void ep0_reinit(struct usb_device *udev)
1994 usb_disable_endpoint(udev, 0 + USB_DIR_IN);
1995 usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
1996 udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
1999 #define usb_sndaddr0pipe() (PIPE_CONTROL << 30)
2000 #define usb_rcvaddr0pipe() ((PIPE_CONTROL << 30) | USB_DIR_IN)
2002 static int hub_set_address(struct usb_device *udev)
2004 int retval;
2006 if (udev->devnum == 0)
2007 return -EINVAL;
2008 if (udev->state == USB_STATE_ADDRESS)
2009 return 0;
2010 if (udev->state != USB_STATE_DEFAULT)
2011 return -EINVAL;
2012 retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2013 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2014 NULL, 0, USB_CTRL_SET_TIMEOUT);
2015 if (retval == 0) {
2016 usb_set_device_state(udev, USB_STATE_ADDRESS);
2017 ep0_reinit(udev);
2019 return retval;
2022 /* Reset device, (re)assign address, get device descriptor.
2023 * Device connection must be stable, no more debouncing needed.
2024 * Returns device in USB_STATE_ADDRESS, except on error.
2026 * If this is called for an already-existing device (as part of
2027 * usb_reset_device), the caller must own the device lock. For a
2028 * newly detected device that is not accessible through any global
2029 * pointers, it's not necessary to lock the device.
2031 static int
2032 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2033 int retry_counter)
2035 static DEFINE_MUTEX(usb_address0_mutex);
2037 struct usb_device *hdev = hub->hdev;
2038 int i, j, retval;
2039 unsigned delay = HUB_SHORT_RESET_TIME;
2040 enum usb_device_speed oldspeed = udev->speed;
2041 char *speed, *type;
2043 /* root hub ports have a slightly longer reset period
2044 * (from USB 2.0 spec, section 7.1.7.5)
2046 if (!hdev->parent) {
2047 delay = HUB_ROOT_RESET_TIME;
2048 if (port1 == hdev->bus->otg_port)
2049 hdev->bus->b_hnp_enable = 0;
2052 /* Some low speed devices have problems with the quick delay, so */
2053 /* be a bit pessimistic with those devices. RHbug #23670 */
2054 if (oldspeed == USB_SPEED_LOW)
2055 delay = HUB_LONG_RESET_TIME;
2057 mutex_lock(&usb_address0_mutex);
2059 /* Reset the device; full speed may morph to high speed */
2060 retval = hub_port_reset(hub, port1, udev, delay);
2061 if (retval < 0) /* error or disconnect */
2062 goto fail;
2063 /* success, speed is known */
2064 retval = -ENODEV;
2066 if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2067 dev_dbg(&udev->dev, "device reset changed speed!\n");
2068 goto fail;
2070 oldspeed = udev->speed;
2072 /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2073 * it's fixed size except for full speed devices.
2074 * For Wireless USB devices, ep0 max packet is always 512 (tho
2075 * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
2077 switch (udev->speed) {
2078 case USB_SPEED_VARIABLE: /* fixed at 512 */
2079 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(512);
2080 break;
2081 case USB_SPEED_HIGH: /* fixed at 64 */
2082 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2083 break;
2084 case USB_SPEED_FULL: /* 8, 16, 32, or 64 */
2085 /* to determine the ep0 maxpacket size, try to read
2086 * the device descriptor to get bMaxPacketSize0 and
2087 * then correct our initial guess.
2089 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2090 break;
2091 case USB_SPEED_LOW: /* fixed at 8 */
2092 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2093 break;
2094 default:
2095 goto fail;
2098 type = "";
2099 switch (udev->speed) {
2100 case USB_SPEED_LOW: speed = "low"; break;
2101 case USB_SPEED_FULL: speed = "full"; break;
2102 case USB_SPEED_HIGH: speed = "high"; break;
2103 case USB_SPEED_VARIABLE:
2104 speed = "variable";
2105 type = "Wireless ";
2106 break;
2107 default: speed = "?"; break;
2109 dev_info (&udev->dev,
2110 "%s %s speed %sUSB device using %s and address %d\n",
2111 (udev->config) ? "reset" : "new", speed, type,
2112 udev->bus->controller->driver->name, udev->devnum);
2114 /* Set up TT records, if needed */
2115 if (hdev->tt) {
2116 udev->tt = hdev->tt;
2117 udev->ttport = hdev->ttport;
2118 } else if (udev->speed != USB_SPEED_HIGH
2119 && hdev->speed == USB_SPEED_HIGH) {
2120 udev->tt = &hub->tt;
2121 udev->ttport = port1;
2124 /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2125 * Because device hardware and firmware is sometimes buggy in
2126 * this area, and this is how Linux has done it for ages.
2127 * Change it cautiously.
2129 * NOTE: If USE_NEW_SCHEME() is true we will start by issuing
2130 * a 64-byte GET_DESCRIPTOR request. This is what Windows does,
2131 * so it may help with some non-standards-compliant devices.
2132 * Otherwise we start with SET_ADDRESS and then try to read the
2133 * first 8 bytes of the device descriptor to get the ep0 maxpacket
2134 * value.
2136 for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2137 if (USE_NEW_SCHEME(retry_counter)) {
2138 struct usb_device_descriptor *buf;
2139 int r = 0;
2141 #define GET_DESCRIPTOR_BUFSIZE 64
2142 buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2143 if (!buf) {
2144 retval = -ENOMEM;
2145 continue;
2148 /* Retry on all errors; some devices are flakey.
2149 * 255 is for WUSB devices, we actually need to use
2150 * 512 (WUSB1.0[4.8.1]).
2152 for (j = 0; j < 3; ++j) {
2153 buf->bMaxPacketSize0 = 0;
2154 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2155 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2156 USB_DT_DEVICE << 8, 0,
2157 buf, GET_DESCRIPTOR_BUFSIZE,
2158 USB_CTRL_GET_TIMEOUT);
2159 switch (buf->bMaxPacketSize0) {
2160 case 8: case 16: case 32: case 64: case 255:
2161 if (buf->bDescriptorType ==
2162 USB_DT_DEVICE) {
2163 r = 0;
2164 break;
2166 /* FALL THROUGH */
2167 default:
2168 if (r == 0)
2169 r = -EPROTO;
2170 break;
2172 if (r == 0)
2173 break;
2175 udev->descriptor.bMaxPacketSize0 =
2176 buf->bMaxPacketSize0;
2177 kfree(buf);
2179 retval = hub_port_reset(hub, port1, udev, delay);
2180 if (retval < 0) /* error or disconnect */
2181 goto fail;
2182 if (oldspeed != udev->speed) {
2183 dev_dbg(&udev->dev,
2184 "device reset changed speed!\n");
2185 retval = -ENODEV;
2186 goto fail;
2188 if (r) {
2189 dev_err(&udev->dev, "device descriptor "
2190 "read/%s, error %d\n",
2191 "64", r);
2192 retval = -EMSGSIZE;
2193 continue;
2195 #undef GET_DESCRIPTOR_BUFSIZE
2198 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2199 retval = hub_set_address(udev);
2200 if (retval >= 0)
2201 break;
2202 msleep(200);
2204 if (retval < 0) {
2205 dev_err(&udev->dev,
2206 "device not accepting address %d, error %d\n",
2207 udev->devnum, retval);
2208 goto fail;
2211 /* cope with hardware quirkiness:
2212 * - let SET_ADDRESS settle, some device hardware wants it
2213 * - read ep0 maxpacket even for high and low speed,
2215 msleep(10);
2216 if (USE_NEW_SCHEME(retry_counter))
2217 break;
2219 retval = usb_get_device_descriptor(udev, 8);
2220 if (retval < 8) {
2221 dev_err(&udev->dev, "device descriptor "
2222 "read/%s, error %d\n",
2223 "8", retval);
2224 if (retval >= 0)
2225 retval = -EMSGSIZE;
2226 } else {
2227 retval = 0;
2228 break;
2231 if (retval)
2232 goto fail;
2234 i = udev->descriptor.bMaxPacketSize0 == 0xff?
2235 512 : udev->descriptor.bMaxPacketSize0;
2236 if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2237 if (udev->speed != USB_SPEED_FULL ||
2238 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2239 dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2240 retval = -EMSGSIZE;
2241 goto fail;
2243 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2244 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2245 ep0_reinit(udev);
2248 retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2249 if (retval < (signed)sizeof(udev->descriptor)) {
2250 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2251 "all", retval);
2252 if (retval >= 0)
2253 retval = -ENOMSG;
2254 goto fail;
2257 retval = 0;
2259 fail:
2260 if (retval)
2261 hub_port_disable(hub, port1, 0);
2262 mutex_unlock(&usb_address0_mutex);
2263 return retval;
2266 static void
2267 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2269 struct usb_qualifier_descriptor *qual;
2270 int status;
2272 qual = kmalloc (sizeof *qual, GFP_KERNEL);
2273 if (qual == NULL)
2274 return;
2276 status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2277 qual, sizeof *qual);
2278 if (status == sizeof *qual) {
2279 dev_info(&udev->dev, "not running at top speed; "
2280 "connect to a high speed hub\n");
2281 /* hub LEDs are probably harder to miss than syslog */
2282 if (hub->has_indicators) {
2283 hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2284 schedule_delayed_work (&hub->leds, 0);
2287 kfree(qual);
2290 static unsigned
2291 hub_power_remaining (struct usb_hub *hub)
2293 struct usb_device *hdev = hub->hdev;
2294 int remaining;
2295 int port1;
2297 if (!hub->limited_power)
2298 return 0;
2300 remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
2301 for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
2302 struct usb_device *udev = hdev->children[port1 - 1];
2303 int delta;
2305 if (!udev)
2306 continue;
2308 /* Unconfigured devices may not use more than 100mA,
2309 * or 8mA for OTG ports */
2310 if (udev->actconfig)
2311 delta = udev->actconfig->desc.bMaxPower * 2;
2312 else if (port1 != udev->bus->otg_port || hdev->parent)
2313 delta = 100;
2314 else
2315 delta = 8;
2316 if (delta > hub->mA_per_port)
2317 dev_warn(&udev->dev, "%dmA is over %umA budget "
2318 "for port %d!\n",
2319 delta, hub->mA_per_port, port1);
2320 remaining -= delta;
2322 if (remaining < 0) {
2323 dev_warn(hub->intfdev, "%dmA over power budget!\n",
2324 - remaining);
2325 remaining = 0;
2327 return remaining;
2330 /* Handle physical or logical connection change events.
2331 * This routine is called when:
2332 * a port connection-change occurs;
2333 * a port enable-change occurs (often caused by EMI);
2334 * usb_reset_device() encounters changed descriptors (as from
2335 * a firmware download)
2336 * caller already locked the hub
2338 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2339 u16 portstatus, u16 portchange)
2341 struct usb_device *hdev = hub->hdev;
2342 struct device *hub_dev = hub->intfdev;
2343 u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2344 int status, i;
2346 dev_dbg (hub_dev,
2347 "port %d, status %04x, change %04x, %s\n",
2348 port1, portstatus, portchange, portspeed (portstatus));
2350 if (hub->has_indicators) {
2351 set_port_led(hub, port1, HUB_LED_AUTO);
2352 hub->indicator[port1-1] = INDICATOR_AUTO;
2355 /* Disconnect any existing devices under this port */
2356 if (hdev->children[port1-1])
2357 usb_disconnect(&hdev->children[port1-1]);
2358 clear_bit(port1, hub->change_bits);
2360 #ifdef CONFIG_USB_OTG
2361 /* during HNP, don't repeat the debounce */
2362 if (hdev->bus->is_b_host)
2363 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2364 #endif
2366 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2367 status = hub_port_debounce(hub, port1);
2368 if (status < 0) {
2369 if (printk_ratelimit())
2370 dev_err (hub_dev, "connect-debounce failed, "
2371 "port %d disabled\n", port1);
2372 goto done;
2374 portstatus = status;
2377 /* Return now if nothing is connected */
2378 if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2380 /* maybe switch power back on (e.g. root hub was reset) */
2381 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
2382 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2383 set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2385 if (portstatus & USB_PORT_STAT_ENABLE)
2386 goto done;
2387 return;
2390 for (i = 0; i < SET_CONFIG_TRIES; i++) {
2391 struct usb_device *udev;
2393 /* reallocate for each attempt, since references
2394 * to the previous one can escape in various ways
2396 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2397 if (!udev) {
2398 dev_err (hub_dev,
2399 "couldn't allocate port %d usb_device\n",
2400 port1);
2401 goto done;
2404 usb_set_device_state(udev, USB_STATE_POWERED);
2405 udev->speed = USB_SPEED_UNKNOWN;
2406 udev->bus_mA = hub->mA_per_port;
2407 udev->level = hdev->level + 1;
2409 /* set the address */
2410 choose_address(udev);
2411 if (udev->devnum <= 0) {
2412 status = -ENOTCONN; /* Don't retry */
2413 goto loop;
2416 /* reset and get descriptor */
2417 status = hub_port_init(hub, udev, port1, i);
2418 if (status < 0)
2419 goto loop;
2421 /* consecutive bus-powered hubs aren't reliable; they can
2422 * violate the voltage drop budget. if the new child has
2423 * a "powered" LED, users should notice we didn't enable it
2424 * (without reading syslog), even without per-port LEDs
2425 * on the parent.
2427 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2428 && udev->bus_mA <= 100) {
2429 u16 devstat;
2431 status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2432 &devstat);
2433 if (status < 2) {
2434 dev_dbg(&udev->dev, "get status %d ?\n", status);
2435 goto loop_disable;
2437 le16_to_cpus(&devstat);
2438 if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2439 dev_err(&udev->dev,
2440 "can't connect bus-powered hub "
2441 "to this port\n");
2442 if (hub->has_indicators) {
2443 hub->indicator[port1-1] =
2444 INDICATOR_AMBER_BLINK;
2445 schedule_delayed_work (&hub->leds, 0);
2447 status = -ENOTCONN; /* Don't retry */
2448 goto loop_disable;
2452 /* check for devices running slower than they could */
2453 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2454 && udev->speed == USB_SPEED_FULL
2455 && highspeed_hubs != 0)
2456 check_highspeed (hub, udev, port1);
2458 /* Store the parent's children[] pointer. At this point
2459 * udev becomes globally accessible, although presumably
2460 * no one will look at it until hdev is unlocked.
2462 status = 0;
2464 /* We mustn't add new devices if the parent hub has
2465 * been disconnected; we would race with the
2466 * recursively_mark_NOTATTACHED() routine.
2468 spin_lock_irq(&device_state_lock);
2469 if (hdev->state == USB_STATE_NOTATTACHED)
2470 status = -ENOTCONN;
2471 else
2472 hdev->children[port1-1] = udev;
2473 spin_unlock_irq(&device_state_lock);
2475 /* Run it through the hoops (find a driver, etc) */
2476 if (!status) {
2477 status = usb_new_device(udev);
2478 if (status) {
2479 spin_lock_irq(&device_state_lock);
2480 hdev->children[port1-1] = NULL;
2481 spin_unlock_irq(&device_state_lock);
2485 if (status)
2486 goto loop_disable;
2488 status = hub_power_remaining(hub);
2489 if (status)
2490 dev_dbg(hub_dev, "%dmA power budget left\n", status);
2492 return;
2494 loop_disable:
2495 hub_port_disable(hub, port1, 1);
2496 loop:
2497 ep0_reinit(udev);
2498 release_address(udev);
2499 usb_put_dev(udev);
2500 if (status == -ENOTCONN)
2501 break;
2504 done:
2505 hub_port_disable(hub, port1, 1);
2508 static void hub_events(void)
2510 struct list_head *tmp;
2511 struct usb_device *hdev;
2512 struct usb_interface *intf;
2513 struct usb_hub *hub;
2514 struct device *hub_dev;
2515 u16 hubstatus;
2516 u16 hubchange;
2517 u16 portstatus;
2518 u16 portchange;
2519 int i, ret;
2520 int connect_change;
2523 * We restart the list every time to avoid a deadlock with
2524 * deleting hubs downstream from this one. This should be
2525 * safe since we delete the hub from the event list.
2526 * Not the most efficient, but avoids deadlocks.
2528 while (1) {
2530 /* Grab the first entry at the beginning of the list */
2531 spin_lock_irq(&hub_event_lock);
2532 if (list_empty(&hub_event_list)) {
2533 spin_unlock_irq(&hub_event_lock);
2534 break;
2537 tmp = hub_event_list.next;
2538 list_del_init(tmp);
2540 hub = list_entry(tmp, struct usb_hub, event_list);
2541 kref_get(&hub->kref);
2542 spin_unlock_irq(&hub_event_lock);
2544 hdev = hub->hdev;
2545 hub_dev = hub->intfdev;
2546 intf = to_usb_interface(hub_dev);
2547 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
2548 hdev->state, hub->descriptor
2549 ? hub->descriptor->bNbrPorts
2550 : 0,
2551 /* NOTE: expects max 15 ports... */
2552 (u16) hub->change_bits[0],
2553 (u16) hub->event_bits[0]);
2555 /* Lock the device, then check to see if we were
2556 * disconnected while waiting for the lock to succeed. */
2557 usb_lock_device(hdev);
2558 if (unlikely(hub->disconnected))
2559 goto loop;
2561 /* If the hub has died, clean up after it */
2562 if (hdev->state == USB_STATE_NOTATTACHED) {
2563 hub->error = -ENODEV;
2564 hub_pre_reset(intf);
2565 goto loop;
2568 /* Autoresume */
2569 ret = usb_autopm_get_interface(intf);
2570 if (ret) {
2571 dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
2572 goto loop;
2575 /* If this is an inactive hub, do nothing */
2576 if (hub->quiescing)
2577 goto loop_autopm;
2579 if (hub->error) {
2580 dev_dbg (hub_dev, "resetting for error %d\n",
2581 hub->error);
2583 ret = usb_reset_composite_device(hdev, intf);
2584 if (ret) {
2585 dev_dbg (hub_dev,
2586 "error resetting hub: %d\n", ret);
2587 goto loop_autopm;
2590 hub->nerrors = 0;
2591 hub->error = 0;
2594 /* deal with port status changes */
2595 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2596 if (test_bit(i, hub->busy_bits))
2597 continue;
2598 connect_change = test_bit(i, hub->change_bits);
2599 if (!test_and_clear_bit(i, hub->event_bits) &&
2600 !connect_change && !hub->activating)
2601 continue;
2603 ret = hub_port_status(hub, i,
2604 &portstatus, &portchange);
2605 if (ret < 0)
2606 continue;
2608 if (hub->activating && !hdev->children[i-1] &&
2609 (portstatus &
2610 USB_PORT_STAT_CONNECTION))
2611 connect_change = 1;
2613 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2614 clear_port_feature(hdev, i,
2615 USB_PORT_FEAT_C_CONNECTION);
2616 connect_change = 1;
2619 if (portchange & USB_PORT_STAT_C_ENABLE) {
2620 if (!connect_change)
2621 dev_dbg (hub_dev,
2622 "port %d enable change, "
2623 "status %08x\n",
2624 i, portstatus);
2625 clear_port_feature(hdev, i,
2626 USB_PORT_FEAT_C_ENABLE);
2629 * EM interference sometimes causes badly
2630 * shielded USB devices to be shutdown by
2631 * the hub, this hack enables them again.
2632 * Works at least with mouse driver.
2634 if (!(portstatus & USB_PORT_STAT_ENABLE)
2635 && !connect_change
2636 && hdev->children[i-1]) {
2637 dev_err (hub_dev,
2638 "port %i "
2639 "disabled by hub (EMI?), "
2640 "re-enabling...\n",
2642 connect_change = 1;
2646 if (portchange & USB_PORT_STAT_C_SUSPEND) {
2647 clear_port_feature(hdev, i,
2648 USB_PORT_FEAT_C_SUSPEND);
2649 if (hdev->children[i-1]) {
2650 ret = remote_wakeup(hdev->
2651 children[i-1]);
2652 if (ret < 0)
2653 connect_change = 1;
2654 } else {
2655 ret = -ENODEV;
2656 hub_port_disable(hub, i, 1);
2658 dev_dbg (hub_dev,
2659 "resume on port %d, status %d\n",
2660 i, ret);
2663 if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2664 dev_err (hub_dev,
2665 "over-current change on port %d\n",
2667 clear_port_feature(hdev, i,
2668 USB_PORT_FEAT_C_OVER_CURRENT);
2669 hub_power_on(hub);
2672 if (portchange & USB_PORT_STAT_C_RESET) {
2673 dev_dbg (hub_dev,
2674 "reset change on port %d\n",
2676 clear_port_feature(hdev, i,
2677 USB_PORT_FEAT_C_RESET);
2680 if (connect_change)
2681 hub_port_connect_change(hub, i,
2682 portstatus, portchange);
2683 } /* end for i */
2685 /* deal with hub status changes */
2686 if (test_and_clear_bit(0, hub->event_bits) == 0)
2687 ; /* do nothing */
2688 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2689 dev_err (hub_dev, "get_hub_status failed\n");
2690 else {
2691 if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2692 dev_dbg (hub_dev, "power change\n");
2693 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2694 if (hubstatus & HUB_STATUS_LOCAL_POWER)
2695 /* FIXME: Is this always true? */
2696 hub->limited_power = 0;
2697 else
2698 hub->limited_power = 1;
2700 if (hubchange & HUB_CHANGE_OVERCURRENT) {
2701 dev_dbg (hub_dev, "overcurrent change\n");
2702 msleep(500); /* Cool down */
2703 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2704 hub_power_on(hub);
2708 hub->activating = 0;
2710 /* If this is a root hub, tell the HCD it's okay to
2711 * re-enable port-change interrupts now. */
2712 if (!hdev->parent && !hub->busy_bits[0])
2713 usb_enable_root_hub_irq(hdev->bus);
2715 loop_autopm:
2716 /* Allow autosuspend if we're not going to run again */
2717 if (list_empty(&hub->event_list))
2718 usb_autopm_enable(intf);
2719 loop:
2720 usb_unlock_device(hdev);
2721 kref_put(&hub->kref, hub_release);
2723 } /* end while (1) */
2726 static int hub_thread(void *__unused)
2728 do {
2729 hub_events();
2730 wait_event_interruptible(khubd_wait,
2731 !list_empty(&hub_event_list) ||
2732 kthread_should_stop());
2733 try_to_freeze();
2734 } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2736 pr_debug("%s: khubd exiting\n", usbcore_name);
2737 return 0;
2740 static struct usb_device_id hub_id_table [] = {
2741 { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2742 .bDeviceClass = USB_CLASS_HUB},
2743 { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2744 .bInterfaceClass = USB_CLASS_HUB},
2745 { } /* Terminating entry */
2748 MODULE_DEVICE_TABLE (usb, hub_id_table);
2750 static struct usb_driver hub_driver = {
2751 .name = "hub",
2752 .probe = hub_probe,
2753 .disconnect = hub_disconnect,
2754 .suspend = hub_suspend,
2755 .resume = hub_resume,
2756 .pre_reset = hub_pre_reset,
2757 .post_reset = hub_post_reset,
2758 .ioctl = hub_ioctl,
2759 .id_table = hub_id_table,
2760 .supports_autosuspend = 1,
2763 int usb_hub_init(void)
2765 if (usb_register(&hub_driver) < 0) {
2766 printk(KERN_ERR "%s: can't register hub driver\n",
2767 usbcore_name);
2768 return -1;
2771 khubd_task = kthread_run(hub_thread, NULL, "khubd");
2772 if (!IS_ERR(khubd_task))
2773 return 0;
2775 /* Fall through if kernel_thread failed */
2776 usb_deregister(&hub_driver);
2777 printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2779 return -1;
2782 void usb_hub_cleanup(void)
2784 kthread_stop(khubd_task);
2787 * Hub resources are freed for us by usb_deregister. It calls
2788 * usb_driver_purge on every device which in turn calls that
2789 * devices disconnect function if it is using this driver.
2790 * The hub_disconnect function takes care of releasing the
2791 * individual hub resources. -greg
2793 usb_deregister(&hub_driver);
2794 } /* usb_hub_cleanup() */
2796 static int config_descriptors_changed(struct usb_device *udev)
2798 unsigned index;
2799 unsigned len = 0;
2800 struct usb_config_descriptor *buf;
2802 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2803 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2804 len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2806 buf = kmalloc (len, GFP_KERNEL);
2807 if (buf == NULL) {
2808 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2809 /* assume the worst */
2810 return 1;
2812 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2813 int length;
2814 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2816 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2817 old_length);
2818 if (length < old_length) {
2819 dev_dbg(&udev->dev, "config index %d, error %d\n",
2820 index, length);
2821 break;
2823 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2824 != 0) {
2825 dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2826 index, buf->bConfigurationValue);
2827 break;
2830 kfree(buf);
2831 return index != udev->descriptor.bNumConfigurations;
2835 * usb_reset_device - perform a USB port reset to reinitialize a device
2836 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2838 * WARNING - don't use this routine to reset a composite device
2839 * (one with multiple interfaces owned by separate drivers)!
2840 * Use usb_reset_composite_device() instead.
2842 * Do a port reset, reassign the device's address, and establish its
2843 * former operating configuration. If the reset fails, or the device's
2844 * descriptors change from their values before the reset, or the original
2845 * configuration and altsettings cannot be restored, a flag will be set
2846 * telling khubd to pretend the device has been disconnected and then
2847 * re-connected. All drivers will be unbound, and the device will be
2848 * re-enumerated and probed all over again.
2850 * Returns 0 if the reset succeeded, -ENODEV if the device has been
2851 * flagged for logical disconnection, or some other negative error code
2852 * if the reset wasn't even attempted.
2854 * The caller must own the device lock. For example, it's safe to use
2855 * this from a driver probe() routine after downloading new firmware.
2856 * For calls that might not occur during probe(), drivers should lock
2857 * the device using usb_lock_device_for_reset().
2859 int usb_reset_device(struct usb_device *udev)
2861 struct usb_device *parent_hdev = udev->parent;
2862 struct usb_hub *parent_hub;
2863 struct usb_device_descriptor descriptor = udev->descriptor;
2864 int i, ret = 0;
2865 int port1 = udev->portnum;
2867 if (udev->state == USB_STATE_NOTATTACHED ||
2868 udev->state == USB_STATE_SUSPENDED) {
2869 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2870 udev->state);
2871 return -EINVAL;
2874 if (!parent_hdev) {
2875 /* this requires hcd-specific logic; see OHCI hc_restart() */
2876 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2877 return -EISDIR;
2879 parent_hub = hdev_to_hub(parent_hdev);
2881 set_bit(port1, parent_hub->busy_bits);
2882 for (i = 0; i < SET_CONFIG_TRIES; ++i) {
2884 /* ep0 maxpacket size may change; let the HCD know about it.
2885 * Other endpoints will be handled by re-enumeration. */
2886 ep0_reinit(udev);
2887 ret = hub_port_init(parent_hub, udev, port1, i);
2888 if (ret >= 0)
2889 break;
2891 clear_bit(port1, parent_hub->busy_bits);
2892 if (!parent_hdev->parent && !parent_hub->busy_bits[0])
2893 usb_enable_root_hub_irq(parent_hdev->bus);
2895 if (ret < 0)
2896 goto re_enumerate;
2898 /* Device might have changed firmware (DFU or similar) */
2899 if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
2900 || config_descriptors_changed (udev)) {
2901 dev_info(&udev->dev, "device firmware changed\n");
2902 udev->descriptor = descriptor; /* for disconnect() calls */
2903 goto re_enumerate;
2906 if (!udev->actconfig)
2907 goto done;
2909 ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2910 USB_REQ_SET_CONFIGURATION, 0,
2911 udev->actconfig->desc.bConfigurationValue, 0,
2912 NULL, 0, USB_CTRL_SET_TIMEOUT);
2913 if (ret < 0) {
2914 dev_err(&udev->dev,
2915 "can't restore configuration #%d (error=%d)\n",
2916 udev->actconfig->desc.bConfigurationValue, ret);
2917 goto re_enumerate;
2919 usb_set_device_state(udev, USB_STATE_CONFIGURED);
2921 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
2922 struct usb_interface *intf = udev->actconfig->interface[i];
2923 struct usb_interface_descriptor *desc;
2925 /* set_interface resets host side toggle even
2926 * for altsetting zero. the interface may have no driver.
2928 desc = &intf->cur_altsetting->desc;
2929 ret = usb_set_interface(udev, desc->bInterfaceNumber,
2930 desc->bAlternateSetting);
2931 if (ret < 0) {
2932 dev_err(&udev->dev, "failed to restore interface %d "
2933 "altsetting %d (error=%d)\n",
2934 desc->bInterfaceNumber,
2935 desc->bAlternateSetting,
2936 ret);
2937 goto re_enumerate;
2941 done:
2942 return 0;
2944 re_enumerate:
2945 hub_port_logical_disconnect(parent_hub, port1);
2946 return -ENODEV;
2948 EXPORT_SYMBOL(usb_reset_device);
2951 * usb_reset_composite_device - warn interface drivers and perform a USB port reset
2952 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2953 * @iface: interface bound to the driver making the request (optional)
2955 * Warns all drivers bound to registered interfaces (using their pre_reset
2956 * method), performs the port reset, and then lets the drivers know that
2957 * the reset is over (using their post_reset method).
2959 * Return value is the same as for usb_reset_device().
2961 * The caller must own the device lock. For example, it's safe to use
2962 * this from a driver probe() routine after downloading new firmware.
2963 * For calls that might not occur during probe(), drivers should lock
2964 * the device using usb_lock_device_for_reset().
2966 * The interface locks are acquired during the pre_reset stage and released
2967 * during the post_reset stage. However if iface is not NULL and is
2968 * currently being probed, we assume that the caller already owns its
2969 * lock.
2971 int usb_reset_composite_device(struct usb_device *udev,
2972 struct usb_interface *iface)
2974 int ret;
2975 struct usb_host_config *config = udev->actconfig;
2977 if (udev->state == USB_STATE_NOTATTACHED ||
2978 udev->state == USB_STATE_SUSPENDED) {
2979 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2980 udev->state);
2981 return -EINVAL;
2984 /* Prevent autosuspend during the reset */
2985 usb_autoresume_device(udev);
2987 if (iface && iface->condition != USB_INTERFACE_BINDING)
2988 iface = NULL;
2990 if (config) {
2991 int i;
2992 struct usb_interface *cintf;
2993 struct usb_driver *drv;
2995 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
2996 cintf = config->interface[i];
2997 if (cintf != iface)
2998 down(&cintf->dev.sem);
2999 if (device_is_registered(&cintf->dev) &&
3000 cintf->dev.driver) {
3001 drv = to_usb_driver(cintf->dev.driver);
3002 if (drv->pre_reset)
3003 (drv->pre_reset)(cintf);
3008 ret = usb_reset_device(udev);
3010 if (config) {
3011 int i;
3012 struct usb_interface *cintf;
3013 struct usb_driver *drv;
3015 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
3016 cintf = config->interface[i];
3017 if (device_is_registered(&cintf->dev) &&
3018 cintf->dev.driver) {
3019 drv = to_usb_driver(cintf->dev.driver);
3020 if (drv->post_reset)
3021 (drv->post_reset)(cintf);
3023 if (cintf != iface)
3024 up(&cintf->dev.sem);
3028 usb_autosuspend_device(udev);
3029 return ret;
3031 EXPORT_SYMBOL(usb_reset_composite_device);