projects / linux-block.git / blame
? search:
summary | shortlog | log | commit | commitdiff | tree
blob | blame (incremental) | history | HEAD
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[linux-block.git] / drivers / usb / core / hub.c
CommitLineData
1da177e4
LT		 1/*
2 * USB hub driver.
3 *
4 * (C) Copyright 1999 Linus Torvalds
5 * (C) Copyright 1999 Johannes Erdfelt
6 * (C) Copyright 1999 Gregory P. Smith
7 * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
8 *
9 */
10
11#include <linux/config.h>
1da177e4
LT		 12#include <linux/kernel.h>
13#include <linux/errno.h>
14#include <linux/module.h>
15#include <linux/moduleparam.h>
16#include <linux/completion.h>
17#include <linux/sched.h>
18#include <linux/list.h>
19#include <linux/slab.h>
20#include <linux/smp_lock.h>
21#include <linux/ioctl.h>
22#include <linux/usb.h>
23#include <linux/usbdevice_fs.h>
9c8d6178 24#include <linux/kthread.h>
4186ecf8 25#include <linux/mutex.h>
1da177e4
LT		 26
27#include <asm/semaphore.h>
28#include <asm/uaccess.h>
29#include <asm/byteorder.h>
30
31#include "usb.h"
32#include "hcd.h"
33#include "hub.h"
34
35/* Protect struct usb_device->state and ->children members
9ad3d6cc 36 * Note: Both are also protected by ->dev.sem, except that ->state can
1da177e4
LT		 37 * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
38static DEFINE_SPINLOCK(device_state_lock);
39
40/* khubd's worklist and its lock */
41static DEFINE_SPINLOCK(hub_event_lock);
42static LIST_HEAD(hub_event_list); /* List of hubs needing servicing */
43
44/* Wakes up khubd */
45static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
46
9c8d6178 47static struct task_struct *khubd_task;
1da177e4
LT		 48
49/* cycle leds on hubs that aren't blinking for attention */
50static int blinkenlights = 0;
51module_param (blinkenlights, bool, S_IRUGO);
52MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
53
54/*
55 * As of 2.6.10 we introduce a new USB device initialization scheme which
56 * closely resembles the way Windows works. Hopefully it will be compatible
57 * with a wider range of devices than the old scheme. However some previously
58 * working devices may start giving rise to "device not accepting address"
59 * errors; if that happens the user can try the old scheme by adjusting the
60 * following module parameters.
61 *
62 * For maximum flexibility there are two boolean parameters to control the
63 * hub driver's behavior. On the first initialization attempt, if the
64 * "old_scheme_first" parameter is set then the old scheme will be used,
65 * otherwise the new scheme is used. If that fails and "use_both_schemes"
66 * is set, then the driver will make another attempt, using the other scheme.
67 */
68static int old_scheme_first = 0;
69module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
70MODULE_PARM_DESC(old_scheme_first,
71 "start with the old device initialization scheme");
72
73static int use_both_schemes = 1;
74module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
75MODULE_PARM_DESC(use_both_schemes,
76 "try the other device initialization scheme if the "
77 "first one fails");
78
79
80#ifdef DEBUG
81static inline char *portspeed (int portstatus)
82{
83 if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
84 return "480 Mb/s";
85 else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
86 return "1.5 Mb/s";
87 else
88 return "12 Mb/s";
89}
90#endif
91
92/* Note that hdev or one of its children must be locked! */
93static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
94{
95 return usb_get_intfdata(hdev->actconfig->interface[0]);
96}
97
98/* USB 2.0 spec Section 11.24.4.5 */
99static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
100{
101 int i, ret;
102
103 for (i = 0; i < 3; i++) {
104 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
105 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
106 USB_DT_HUB << 8, 0, data, size,
107 USB_CTRL_GET_TIMEOUT);
108 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
109 return ret;
110 }
111 return -EINVAL;
112}
113
114/*
115 * USB 2.0 spec Section 11.24.2.1
116 */
117static int clear_hub_feature(struct usb_device *hdev, int feature)
118{
119 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
120 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
121}
122
123/*
124 * USB 2.0 spec Section 11.24.2.2
125 */
126static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
127{
128 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
129 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
130 NULL, 0, 1000);
131}
132
133/*
134 * USB 2.0 spec Section 11.24.2.13
135 */
136static int set_port_feature(struct usb_device *hdev, int port1, int feature)
137{
138 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
139 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
140 NULL, 0, 1000);
141}
142
143/*
144 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
145 * for info about using port indicators
146 */
147static void set_port_led(
148 struct usb_hub *hub,
149 int port1,
150 int selector
151)
152{
153 int status = set_port_feature(hub->hdev, (selector << 8) | port1,
154 USB_PORT_FEAT_INDICATOR);
155 if (status < 0)
156 dev_dbg (hub->intfdev,
157 "port %d indicator %s status %d\n",
158 port1,
159 ({ char *s; switch (selector) {
160 case HUB_LED_AMBER: s = "amber"; break;
161 case HUB_LED_GREEN: s = "green"; break;
162 case HUB_LED_OFF: s = "off"; break;
163 case HUB_LED_AUTO: s = "auto"; break;
164 default: s = "??"; break;
165 }; s; }),
166 status);
167}
168
169#define LED_CYCLE_PERIOD ((2*HZ)/3)
170
171static void led_work (void *__hub)
172{
173 struct usb_hub *hub = __hub;
174 struct usb_device *hdev = hub->hdev;
175 unsigned i;
176 unsigned changed = 0;
177 int cursor = -1;
178
179 if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
180 return;
181
182 for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
183 unsigned selector, mode;
184
185 /* 30%-50% duty cycle */
186
187 switch (hub->indicator[i]) {
188 /* cycle marker */
189 case INDICATOR_CYCLE:
190 cursor = i;
191 selector = HUB_LED_AUTO;
192 mode = INDICATOR_AUTO;
193 break;
194 /* blinking green = sw attention */
195 case INDICATOR_GREEN_BLINK:
196 selector = HUB_LED_GREEN;
197 mode = INDICATOR_GREEN_BLINK_OFF;
198 break;
199 case INDICATOR_GREEN_BLINK_OFF:
200 selector = HUB_LED_OFF;
201 mode = INDICATOR_GREEN_BLINK;
202 break;
203 /* blinking amber = hw attention */
204 case INDICATOR_AMBER_BLINK:
205 selector = HUB_LED_AMBER;
206 mode = INDICATOR_AMBER_BLINK_OFF;
207 break;
208 case INDICATOR_AMBER_BLINK_OFF:
209 selector = HUB_LED_OFF;
210 mode = INDICATOR_AMBER_BLINK;
211 break;
212 /* blink green/amber = reserved */
213 case INDICATOR_ALT_BLINK:
214 selector = HUB_LED_GREEN;
215 mode = INDICATOR_ALT_BLINK_OFF;
216 break;
217 case INDICATOR_ALT_BLINK_OFF:
218 selector = HUB_LED_AMBER;
219 mode = INDICATOR_ALT_BLINK;
220 break;
221 default:
222 continue;
223 }
224 if (selector != HUB_LED_AUTO)
225 changed = 1;
226 set_port_led(hub, i + 1, selector);
227 hub->indicator[i] = mode;
228 }
229 if (!changed && blinkenlights) {
230 cursor++;
231 cursor %= hub->descriptor->bNbrPorts;
232 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
233 hub->indicator[cursor] = INDICATOR_CYCLE;
234 changed++;
235 }
236 if (changed)
237 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
238}
239
240/* use a short timeout for hub/port status fetches */
241#define USB_STS_TIMEOUT 1000
242#define USB_STS_RETRIES 5
243
244/*
245 * USB 2.0 spec Section 11.24.2.6
246 */
247static int get_hub_status(struct usb_device *hdev,
248 struct usb_hub_status *data)
249{
250 int i, status = -ETIMEDOUT;
251
252 for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
253 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
254 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
255 data, sizeof(*data), USB_STS_TIMEOUT);
256 }
257 return status;
258}
259
260/*
261 * USB 2.0 spec Section 11.24.2.7
262 */
263static int get_port_status(struct usb_device *hdev, int port1,
264 struct usb_port_status *data)
265{
266 int i, status = -ETIMEDOUT;
267
268 for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
269 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
270 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
271 data, sizeof(*data), USB_STS_TIMEOUT);
272 }
273 return status;
274}
275
276static void kick_khubd(struct usb_hub *hub)
277{
278 unsigned long flags;
279
280 spin_lock_irqsave(&hub_event_lock, flags);
281 if (list_empty(&hub->event_list)) {
282 list_add_tail(&hub->event_list, &hub_event_list);
283 wake_up(&khubd_wait);
284 }
285 spin_unlock_irqrestore(&hub_event_lock, flags);
286}
287
288void usb_kick_khubd(struct usb_device *hdev)
289{
290 kick_khubd(hdev_to_hub(hdev));
291}
292
293
294/* completion function, fires on port status changes and various faults */
295static void hub_irq(struct urb *urb, struct pt_regs *regs)
296{
297 struct usb_hub *hub = (struct usb_hub *)urb->context;
298 int status;
299 int i;
300 unsigned long bits;
301
302 switch (urb->status) {
303 case -ENOENT: /* synchronous unlink */
304 case -ECONNRESET: /* async unlink */
305 case -ESHUTDOWN: /* hardware going away */
306 return;
307
308 default: /* presumably an error */
309 /* Cause a hub reset after 10 consecutive errors */
310 dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
311 if ((++hub->nerrors < 10) || hub->error)
312 goto resubmit;
313 hub->error = urb->status;
314 /* FALL THROUGH */
315
316 /* let khubd handle things */
317 case 0: /* we got data: port status changed */
318 bits = 0;
319 for (i = 0; i < urb->actual_length; ++i)
320 bits |= ((unsigned long) ((*hub->buffer)[i]))
321 << (i*8);
322 hub->event_bits[0] = bits;
323 break;
324 }
325
326 hub->nerrors = 0;
327
328 /* Something happened, let khubd figure it out */
329 kick_khubd(hub);
330
331resubmit:
332 if (hub->quiescing)
333 return;
334
335 if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
336 && status != -ENODEV && status != -EPERM)
337 dev_err (hub->intfdev, "resubmit --> %d\n", status);
338}
339
340/* USB 2.0 spec Section 11.24.2.3 */
341static inline int
342hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
343{
344 return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
345 HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
346 tt, NULL, 0, 1000);
347}
348
349/*
350 * enumeration blocks khubd for a long time. we use keventd instead, since
351 * long blocking there is the exception, not the rule. accordingly, HCDs
352 * talking to TTs must queue control transfers (not just bulk and iso), so
353 * both can talk to the same hub concurrently.
354 */
355static void hub_tt_kevent (void *arg)
356{
357 struct usb_hub *hub = arg;
358 unsigned long flags;
359
360 spin_lock_irqsave (&hub->tt.lock, flags);
361 while (!list_empty (&hub->tt.clear_list)) {
362 struct list_head *temp;
363 struct usb_tt_clear *clear;
364 struct usb_device *hdev = hub->hdev;
365 int status;
366
367 temp = hub->tt.clear_list.next;
368 clear = list_entry (temp, struct usb_tt_clear, clear_list);
369 list_del (&clear->clear_list);
370
371 /* drop lock so HCD can concurrently report other TT errors */
372 spin_unlock_irqrestore (&hub->tt.lock, flags);
373 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
374 spin_lock_irqsave (&hub->tt.lock, flags);
375
376 if (status)
377 dev_err (&hdev->dev,
378 "clear tt %d (%04x) error %d\n",
379 clear->tt, clear->devinfo, status);
1bc3c9e1 380 kfree(clear);
1da177e4
LT		 381 }
382 spin_unlock_irqrestore (&hub->tt.lock, flags);
383}
384
385/**
386 * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
387 * @udev: the device whose split transaction failed
388 * @pipe: identifies the endpoint of the failed transaction
389 *
390 * High speed HCDs use this to tell the hub driver that some split control or
391 * bulk transaction failed in a way that requires clearing internal state of
392 * a transaction translator. This is normally detected (and reported) from
393 * interrupt context.
394 *
395 * It may not be possible for that hub to handle additional full (or low)
396 * speed transactions until that state is fully cleared out.
397 */
398void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
399{
400 struct usb_tt *tt = udev->tt;
401 unsigned long flags;
402 struct usb_tt_clear *clear;
403
404 /* we've got to cope with an arbitrary number of pending TT clears,
405 * since each TT has "at least two" buffers that can need it (and
406 * there can be many TTs per hub). even if they're uncommon.
407 */
408 if ((clear = kmalloc (sizeof *clear, SLAB_ATOMIC)) == NULL) {
409 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
410 /* FIXME recover somehow ... RESET_TT? */
411 return;
412 }
413
414 /* info that CLEAR_TT_BUFFER needs */
415 clear->tt = tt->multi ? udev->ttport : 1;
416 clear->devinfo = usb_pipeendpoint (pipe);
417 clear->devinfo |= udev->devnum << 4;
418 clear->devinfo |= usb_pipecontrol (pipe)
419 ? (USB_ENDPOINT_XFER_CONTROL << 11)
420 : (USB_ENDPOINT_XFER_BULK << 11);
421 if (usb_pipein (pipe))
422 clear->devinfo |= 1 << 15;
423
424 /* tell keventd to clear state for this TT */
425 spin_lock_irqsave (&tt->lock, flags);
426 list_add_tail (&clear->clear_list, &tt->clear_list);
427 schedule_work (&tt->kevent);
428 spin_unlock_irqrestore (&tt->lock, flags);
429}
430
431static void hub_power_on(struct usb_hub *hub)
432{
433 int port1;
b789696a 434 unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
4489a571
AS		 435 u16 wHubCharacteristics =
436 le16_to_cpu(hub->descriptor->wHubCharacteristics);
437
438 /* Enable power on each port. Some hubs have reserved values
439 * of LPSM (> 2) in their descriptors, even though they are
440 * USB 2.0 hubs. Some hubs do not implement port-power switching
441 * but only emulate it. In all cases, the ports won't work
442 * unless we send these messages to the hub.
443 */
444 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
1da177e4 445 dev_dbg(hub->intfdev, "enabling power on all ports\n");
4489a571
AS		 446 else
447 dev_dbg(hub->intfdev, "trying to enable port power on "
448 "non-switchable hub\n");
449 for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
450 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
1da177e4 451
b789696a
DB		 452 /* Wait at least 100 msec for power to become stable */
453 msleep(max(pgood_delay, (unsigned) 100));
1da177e4
LT		 454}
455
979d5199 456static inline void __hub_quiesce(struct usb_hub *hub)
1da177e4 457{
979d5199 458 /* (nonblocking) khubd and related activity won't re-trigger */
1da177e4 459 hub->quiescing = 1;
c9f89fa4 460 hub->activating = 0;
979d5199
DB		 461 hub->resume_root_hub = 0;
462}
463
464static void hub_quiesce(struct usb_hub *hub)
465{
466 /* (blocking) stop khubd and related activity */
467 __hub_quiesce(hub);
1da177e4
LT		 468 usb_kill_urb(hub->urb);
469 if (hub->has_indicators)
470 cancel_delayed_work(&hub->leds);
471 if (hub->has_indicators || hub->tt.hub)
472 flush_scheduled_work();
473}
474
475static void hub_activate(struct usb_hub *hub)
476{
477 int status;
478
479 hub->quiescing = 0;
480 hub->activating = 1;
979d5199 481 hub->resume_root_hub = 0;
1da177e4
LT		 482 status = usb_submit_urb(hub->urb, GFP_NOIO);
483 if (status < 0)
484 dev_err(hub->intfdev, "activate --> %d\n", status);
485 if (hub->has_indicators && blinkenlights)
486 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
487
488 /* scan all ports ASAP */
489 kick_khubd(hub);
490}
491
492static int hub_hub_status(struct usb_hub *hub,
493 u16 *status, u16 *change)
494{
495 int ret;
496
497 ret = get_hub_status(hub->hdev, &hub->status->hub);
498 if (ret < 0)
499 dev_err (hub->intfdev,
500 "%s failed (err = %d)\n", __FUNCTION__, ret);
501 else {
502 *status = le16_to_cpu(hub->status->hub.wHubStatus);
503 *change = le16_to_cpu(hub->status->hub.wHubChange);
504 ret = 0;
505 }
506 return ret;
507}
508
8b28c752
AS		 509static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
510{
511 struct usb_device *hdev = hub->hdev;
512 int ret;
513
514 if (hdev->children[port1-1] && set_state) {
515 usb_set_device_state(hdev->children[port1-1],
516 USB_STATE_NOTATTACHED);
517 }
518 ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
519 if (ret)
520 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
521 port1, ret);
522
523 return ret;
524}
525
7d069b7d
AS		 526
527/* caller has locked the hub device */
7de18d8b 528static void hub_pre_reset(struct usb_interface *intf)
7d069b7d 529{
7de18d8b 530 struct usb_hub *hub = usb_get_intfdata(intf);
7d069b7d
AS		 531 struct usb_device *hdev = hub->hdev;
532 int port1;
533
534 for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
535 if (hdev->children[port1 - 1]) {
536 usb_disconnect(&hdev->children[port1 - 1]);
7de18d8b 537 if (hub->error == 0)
7d069b7d
AS		 538 hub_port_disable(hub, port1, 0);
539 }
540 }
541 hub_quiesce(hub);
542}
543
544/* caller has locked the hub device */
7de18d8b 545static void hub_post_reset(struct usb_interface *intf)
7d069b7d 546{
7de18d8b
AS		 547 struct usb_hub *hub = usb_get_intfdata(intf);
548
7d069b7d
AS		 549 hub_activate(hub);
550 hub_power_on(hub);
551}
552
553
1da177e4
LT		 554static int hub_configure(struct usb_hub *hub,
555 struct usb_endpoint_descriptor *endpoint)
556{
557 struct usb_device *hdev = hub->hdev;
558 struct device *hub_dev = hub->intfdev;
559 u16 hubstatus, hubchange;
74ad9bd2 560 u16 wHubCharacteristics;
1da177e4
LT		 561 unsigned int pipe;
562 int maxp, ret;
563 char *message;
564
565 hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
566 &hub->buffer_dma);
567 if (!hub->buffer) {
568 message = "can't allocate hub irq buffer";
569 ret = -ENOMEM;
570 goto fail;
571 }
572
573 hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
574 if (!hub->status) {
575 message = "can't kmalloc hub status buffer";
576 ret = -ENOMEM;
577 goto fail;
578 }
579
580 hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
581 if (!hub->descriptor) {
582 message = "can't kmalloc hub descriptor";
583 ret = -ENOMEM;
584 goto fail;
585 }
586
587 /* Request the entire hub descriptor.
588 * hub->descriptor can handle USB_MAXCHILDREN ports,
589 * but the hub can/will return fewer bytes here.
590 */
591 ret = get_hub_descriptor(hdev, hub->descriptor,
592 sizeof(*hub->descriptor));
593 if (ret < 0) {
594 message = "can't read hub descriptor";
595 goto fail;
596 } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
597 message = "hub has too many ports!";
598 ret = -ENODEV;
599 goto fail;
600 }
601
602 hdev->maxchild = hub->descriptor->bNbrPorts;
603 dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
604 (hdev->maxchild == 1) ? "" : "s");
605
74ad9bd2 606 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
1da177e4 607
74ad9bd2 608 if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
1da177e4
LT		 609 int i;
610 char portstr [USB_MAXCHILDREN + 1];
611
612 for (i = 0; i < hdev->maxchild; i++)
613 portstr[i] = hub->descriptor->DeviceRemovable
614 [((i + 1) / 8)] & (1 << ((i + 1) % 8))
615 ? 'F' : 'R';
616 portstr[hdev->maxchild] = 0;
617 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
618 } else
619 dev_dbg(hub_dev, "standalone hub\n");
620
74ad9bd2 621 switch (wHubCharacteristics & HUB_CHAR_LPSM) {
1da177e4
LT		 622 case 0x00:
623 dev_dbg(hub_dev, "ganged power switching\n");
624 break;
625 case 0x01:
626 dev_dbg(hub_dev, "individual port power switching\n");
627 break;
628 case 0x02:
629 case 0x03:
630 dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
631 break;
632 }
633
74ad9bd2 634 switch (wHubCharacteristics & HUB_CHAR_OCPM) {
1da177e4
LT		 635 case 0x00:
636 dev_dbg(hub_dev, "global over-current protection\n");
637 break;
638 case 0x08:
639 dev_dbg(hub_dev, "individual port over-current protection\n");
640 break;
641 case 0x10:
642 case 0x18:
643 dev_dbg(hub_dev, "no over-current protection\n");
644 break;
645 }
646
647 spin_lock_init (&hub->tt.lock);
648 INIT_LIST_HEAD (&hub->tt.clear_list);
649 INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub);
650 switch (hdev->descriptor.bDeviceProtocol) {
651 case 0:
652 break;
653 case 1:
654 dev_dbg(hub_dev, "Single TT\n");
655 hub->tt.hub = hdev;
656 break;
657 case 2:
658 ret = usb_set_interface(hdev, 0, 1);
659 if (ret == 0) {
660 dev_dbg(hub_dev, "TT per port\n");
661 hub->tt.multi = 1;
662 } else
663 dev_err(hub_dev, "Using single TT (err %d)\n",
664 ret);
665 hub->tt.hub = hdev;
666 break;
667 default:
668 dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
669 hdev->descriptor.bDeviceProtocol);
670 break;
671 }
672
e09711ae 673 /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
74ad9bd2 674 switch (wHubCharacteristics & HUB_CHAR_TTTT) {
e09711ae 675 case HUB_TTTT_8_BITS:
676 if (hdev->descriptor.bDeviceProtocol != 0) {
677 hub->tt.think_time = 666;
678 dev_dbg(hub_dev, "TT requires at most %d "
679 "FS bit times (%d ns)\n",
680 8, hub->tt.think_time);
681 }
1da177e4 682 break;
e09711ae 683 case HUB_TTTT_16_BITS:
684 hub->tt.think_time = 666 * 2;
685 dev_dbg(hub_dev, "TT requires at most %d "
686 "FS bit times (%d ns)\n",
687 16, hub->tt.think_time);
1da177e4 688 break;
e09711ae 689 case HUB_TTTT_24_BITS:
690 hub->tt.think_time = 666 * 3;
691 dev_dbg(hub_dev, "TT requires at most %d "
692 "FS bit times (%d ns)\n",
693 24, hub->tt.think_time);
1da177e4 694 break;
e09711ae 695 case HUB_TTTT_32_BITS:
696 hub->tt.think_time = 666 * 4;
697 dev_dbg(hub_dev, "TT requires at most %d "
698 "FS bit times (%d ns)\n",
699 32, hub->tt.think_time);
1da177e4
LT		 700 break;
701 }
702
703 /* probe() zeroes hub->indicator[] */
74ad9bd2 704 if (wHubCharacteristics & HUB_CHAR_PORTIND) {
1da177e4
LT		 705 hub->has_indicators = 1;
706 dev_dbg(hub_dev, "Port indicators are supported\n");
707 }
708
709 dev_dbg(hub_dev, "power on to power good time: %dms\n",
710 hub->descriptor->bPwrOn2PwrGood * 2);
711
712 /* power budgeting mostly matters with bus-powered hubs,
713 * and battery-powered root hubs (may provide just 8 mA).
714 */
715 ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
55c52718 716 if (ret < 2) {
1da177e4
LT		 717 message = "can't get hub status";
718 goto fail;
719 }
7d35b929
AS		 720 le16_to_cpus(&hubstatus);
721 if (hdev == hdev->bus->root_hub) {
55c52718
AS		 722 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
723 hub->mA_per_port = 500;
724 else {
725 hub->mA_per_port = hdev->bus_mA;
726 hub->limited_power = 1;
727 }
7d35b929 728 } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1da177e4
LT		 729 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
730 hub->descriptor->bHubContrCurrent);
55c52718
AS		 731 hub->limited_power = 1;
732 if (hdev->maxchild > 0) {
733 int remaining = hdev->bus_mA -
734 hub->descriptor->bHubContrCurrent;
735
736 if (remaining < hdev->maxchild * 100)
737 dev_warn(hub_dev,
738 "insufficient power available "
739 "to use all downstream ports\n");
740 hub->mA_per_port = 100; /* 7.2.1.1 */
741 }
742 } else { /* Self-powered external hub */
743 /* FIXME: What about battery-powered external hubs that
744 * provide less current per port? */
745 hub->mA_per_port = 500;
7d35b929 746 }
55c52718
AS		 747 if (hub->mA_per_port < 500)
748 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
749 hub->mA_per_port);
1da177e4
LT		 750
751 ret = hub_hub_status(hub, &hubstatus, &hubchange);
752 if (ret < 0) {
753 message = "can't get hub status";
754 goto fail;
755 }
756
757 /* local power status reports aren't always correct */
758 if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
759 dev_dbg(hub_dev, "local power source is %s\n",
760 (hubstatus & HUB_STATUS_LOCAL_POWER)
761 ? "lost (inactive)" : "good");
762
74ad9bd2 763 if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
1da177e4
LT		 764 dev_dbg(hub_dev, "%sover-current condition exists\n",
765 (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
766
767 /* set up the interrupt endpoint */
768 pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
769 maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
770
771 if (maxp > sizeof(*hub->buffer))
772 maxp = sizeof(*hub->buffer);
773
774 hub->urb = usb_alloc_urb(0, GFP_KERNEL);
775 if (!hub->urb) {
776 message = "couldn't allocate interrupt urb";
777 ret = -ENOMEM;
778 goto fail;
779 }
780
781 usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
782 hub, endpoint->bInterval);
783 hub->urb->transfer_dma = hub->buffer_dma;
784 hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
785
786 /* maybe cycle the hub leds */
787 if (hub->has_indicators && blinkenlights)
788 hub->indicator [0] = INDICATOR_CYCLE;
789
790 hub_power_on(hub);
791 hub_activate(hub);
792 return 0;
793
794fail:
795 dev_err (hub_dev, "config failed, %s (err %d)\n",
796 message, ret);
797 /* hub_disconnect() frees urb and descriptor */
798 return ret;
799}
800
801static unsigned highspeed_hubs;
802
803static void hub_disconnect(struct usb_interface *intf)
804{
805 struct usb_hub *hub = usb_get_intfdata (intf);
806 struct usb_device *hdev;
807
7de18d8b
AS		 808 /* Disconnect all children and quiesce the hub */
809 hub->error = 0;
810 hub_pre_reset(intf);
811
8b28c752 812 usb_set_intfdata (intf, NULL);
1da177e4
LT		 813 hdev = hub->hdev;
814
815 if (hdev->speed == USB_SPEED_HIGH)
816 highspeed_hubs--;
817
1da177e4
LT		 818 usb_free_urb(hub->urb);
819 hub->urb = NULL;
820
821 spin_lock_irq(&hub_event_lock);
822 list_del_init(&hub->event_list);
823 spin_unlock_irq(&hub_event_lock);
824
1bc3c9e1
JJ		 825 kfree(hub->descriptor);
826 hub->descriptor = NULL;
1da177e4 827
1bc3c9e1
JJ		 828 kfree(hub->status);
829 hub->status = NULL;
1da177e4
LT		 830
831 if (hub->buffer) {
832 usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
833 hub->buffer_dma);
834 hub->buffer = NULL;
835 }
836
7d069b7d 837 kfree(hub);
1da177e4
LT		 838}
839
840static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
841{
842 struct usb_host_interface *desc;
843 struct usb_endpoint_descriptor *endpoint;
844 struct usb_device *hdev;
845 struct usb_hub *hub;
846
847 desc = intf->cur_altsetting;
848 hdev = interface_to_usbdev(intf);
849
89ccbdc9
DB		 850#ifdef CONFIG_USB_OTG_BLACKLIST_HUB
851 if (hdev->parent) {
852 dev_warn(&intf->dev, "ignoring external hub\n");
853 return -ENODEV;
854 }
855#endif
856
1da177e4
LT		 857 /* Some hubs have a subclass of 1, which AFAICT according to the */
858 /* specs is not defined, but it works */
859 if ((desc->desc.bInterfaceSubClass != 0) &&
860 (desc->desc.bInterfaceSubClass != 1)) {
861descriptor_error:
862 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
863 return -EIO;
864 }
865
866 /* Multiple endpoints? What kind of mutant ninja-hub is this? */
867 if (desc->desc.bNumEndpoints != 1)
868 goto descriptor_error;
869
870 endpoint = &desc->endpoint[0].desc;
871
872 /* Output endpoint? Curiouser and curiouser.. */
873 if (!(endpoint->bEndpointAddress & USB_DIR_IN))
874 goto descriptor_error;
875
876 /* If it's not an interrupt endpoint, we'd better punt! */
877 if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
878 != USB_ENDPOINT_XFER_INT)
879 goto descriptor_error;
880
881 /* We found a hub */
882 dev_info (&intf->dev, "USB hub found\n");
883
0a1ef3b5 884 hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1da177e4
LT		 885 if (!hub) {
886 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
887 return -ENOMEM;
888 }
889
1da177e4
LT		 890 INIT_LIST_HEAD(&hub->event_list);
891 hub->intfdev = &intf->dev;
892 hub->hdev = hdev;
893 INIT_WORK(&hub->leds, led_work, hub);
894
895 usb_set_intfdata (intf, hub);
896
897 if (hdev->speed == USB_SPEED_HIGH)
898 highspeed_hubs++;
899
900 if (hub_configure(hub, endpoint) >= 0)
901 return 0;
902
903 hub_disconnect (intf);
904 return -ENODEV;
905}
906
907static int
908hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
909{
910 struct usb_device *hdev = interface_to_usbdev (intf);
911
912 /* assert ifno == 0 (part of hub spec) */
913 switch (code) {
914 case USBDEVFS_HUB_PORTINFO: {
915 struct usbdevfs_hub_portinfo *info = user_data;
916 int i;
917
918 spin_lock_irq(&device_state_lock);
919 if (hdev->devnum <= 0)
920 info->nports = 0;
921 else {
922 info->nports = hdev->maxchild;
923 for (i = 0; i < info->nports; i++) {
924 if (hdev->children[i] == NULL)
925 info->port[i] = 0;
926 else
927 info->port[i] =
928 hdev->children[i]->devnum;
929 }
930 }
931 spin_unlock_irq(&device_state_lock);
932
933 return info->nports + 1;
934 }
935
936 default:
937 return -ENOSYS;
938 }
939}
940
1da177e4
LT		 941
942/* grab device/port lock, returning index of that port (zero based).
943 * protects the upstream link used by this device from concurrent
944 * tree operations like suspend, resume, reset, and disconnect, which
945 * apply to everything downstream of a given port.
946 */
947static int locktree(struct usb_device *udev)
948{
949 int t;
950 struct usb_device *hdev;
951
952 if (!udev)
953 return -ENODEV;
954
955 /* root hub is always the first lock in the series */
956 hdev = udev->parent;
957 if (!hdev) {
958 usb_lock_device(udev);
959 return 0;
960 }
961
962 /* on the path from root to us, lock everything from
963 * top down, dropping parent locks when not needed
964 */
965 t = locktree(hdev);
966 if (t < 0)
967 return t;
1da177e4 968
12c3da34
AS		 969 /* everything is fail-fast once disconnect
970 * processing starts
971 */
972 if (udev->state == USB_STATE_NOTATTACHED) {
973 usb_unlock_device(hdev);
974 return -ENODEV;
1da177e4 975 }
12c3da34
AS		 976
977 /* when everyone grabs locks top->bottom,
978 * non-overlapping work may be concurrent
979 */
980 usb_lock_device(udev);
1da177e4 981 usb_unlock_device(hdev);
12c3da34 982 return udev->portnum;
1da177e4
LT		 983}
984
985static void recursively_mark_NOTATTACHED(struct usb_device *udev)
986{
987 int i;
988
989 for (i = 0; i < udev->maxchild; ++i) {
990 if (udev->children[i])
991 recursively_mark_NOTATTACHED(udev->children[i]);
992 }
993 udev->state = USB_STATE_NOTATTACHED;
994}
995
996/**
997 * usb_set_device_state - change a device's current state (usbcore, hcds)
998 * @udev: pointer to device whose state should be changed
999 * @new_state: new state value to be stored
1000 *
1001 * udev->state is _not_ fully protected by the device lock. Although
1002 * most transitions are made only while holding the lock, the state can
1003 * can change to USB_STATE_NOTATTACHED at almost any time. This
1004 * is so that devices can be marked as disconnected as soon as possible,
1005 * without having to wait for any semaphores to be released. As a result,
1006 * all changes to any device's state must be protected by the
1007 * device_state_lock spinlock.
1008 *
1009 * Once a device has been added to the device tree, all changes to its state
1010 * should be made using this routine. The state should _not_ be set directly.
1011 *
1012 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1013 * Otherwise udev->state is set to new_state, and if new_state is
1014 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1015 * to USB_STATE_NOTATTACHED.
1016 */
1017void usb_set_device_state(struct usb_device *udev,
1018 enum usb_device_state new_state)
1019{
1020 unsigned long flags;
1021
1022 spin_lock_irqsave(&device_state_lock, flags);
1023 if (udev->state == USB_STATE_NOTATTACHED)
1024 ; /* do nothing */
b94dc6b5 1025 else if (new_state != USB_STATE_NOTATTACHED) {
1da177e4 1026 udev->state = new_state;
fb669cc0
DB		 1027
1028 /* root hub wakeup capabilities are managed out-of-band
1029 * and may involve silicon errata ... ignore them here.
1030 */
1031 if (udev->parent) {
1032 if (new_state == USB_STATE_CONFIGURED)
1033 device_init_wakeup(&udev->dev,
1034 (udev->actconfig->desc.bmAttributes
1035 & USB_CONFIG_ATT_WAKEUP));
1036 else if (new_state != USB_STATE_SUSPENDED)
1037 device_init_wakeup(&udev->dev, 0);
1038 }
b94dc6b5 1039 } else
1da177e4
LT		 1040 recursively_mark_NOTATTACHED(udev);
1041 spin_unlock_irqrestore(&device_state_lock, flags);
1042}
1da177e4
LT		 1043
1044
1c50c317
AS		 1045#ifdef CONFIG_PM
1046
1047/**
1048 * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
1049 * @rhdev: struct usb_device for the root hub
1050 *
1051 * The USB host controller driver calls this function when its root hub
1052 * is resumed and Vbus power has been interrupted or the controller
1053 * has been reset. The routine marks all the children of the root hub
1054 * as NOTATTACHED and marks logical connect-change events on their ports.
1055 */
1056void usb_root_hub_lost_power(struct usb_device *rhdev)
1057{
1058 struct usb_hub *hub;
1059 int port1;
1060 unsigned long flags;
1061
1062 dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
1063 spin_lock_irqsave(&device_state_lock, flags);
1064 hub = hdev_to_hub(rhdev);
1065 for (port1 = 1; port1 <= rhdev->maxchild; ++port1) {
1066 if (rhdev->children[port1 - 1]) {
1067 recursively_mark_NOTATTACHED(
1068 rhdev->children[port1 - 1]);
1069 set_bit(port1, hub->change_bits);
1070 }
1071 }
1072 spin_unlock_irqrestore(&device_state_lock, flags);
1073}
1074EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
1075
1076#endif
1077
1da177e4
LT		 1078static void choose_address(struct usb_device *udev)
1079{
1080 int devnum;
1081 struct usb_bus *bus = udev->bus;
1082
1083 /* If khubd ever becomes multithreaded, this will need a lock */
1084
1085 /* Try to allocate the next devnum beginning at bus->devnum_next. */
1086 devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1087 bus->devnum_next);
1088 if (devnum >= 128)
1089 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1090
1091 bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1092
1093 if (devnum < 128) {
1094 set_bit(devnum, bus->devmap.devicemap);
1095 udev->devnum = devnum;
1096 }
1097}
1098
1099static void release_address(struct usb_device *udev)
1100{
1101 if (udev->devnum > 0) {
1102 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1103 udev->devnum = -1;
1104 }
1105}
1106
1107/**
1108 * usb_disconnect - disconnect a device (usbcore-internal)
1109 * @pdev: pointer to device being disconnected
1110 * Context: !in_interrupt ()
1111 *
1112 * Something got disconnected. Get rid of it and all of its children.
1113 *
1114 * If *pdev is a normal device then the parent hub must already be locked.
1115 * If *pdev is a root hub then this routine will acquire the
1116 * usb_bus_list_lock on behalf of the caller.
1117 *
1118 * Only hub drivers (including virtual root hub drivers for host
1119 * controllers) should ever call this.
1120 *
1121 * This call is synchronous, and may not be used in an interrupt context.
1122 */
1123void usb_disconnect(struct usb_device **pdev)
1124{
1125 struct usb_device *udev = *pdev;
1126 int i;
1127
1128 if (!udev) {
1129 pr_debug ("%s nodev\n", __FUNCTION__);
1130 return;
1131 }
1132
1133 /* mark the device as inactive, so any further urb submissions for
1134 * this device (and any of its children) will fail immediately.
1135 * this quiesces everyting except pending urbs.
1136 */
1137 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1da177e4
LT		 1138 dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1139
9ad3d6cc
AS		 1140 usb_lock_device(udev);
1141
1da177e4
LT		 1142 /* Free up all the children before we remove this device */
1143 for (i = 0; i < USB_MAXCHILDREN; i++) {
1144 if (udev->children[i])
1145 usb_disconnect(&udev->children[i]);
1146 }
1147
1148 /* deallocate hcd/hardware state ... nuking all pending urbs and
1149 * cleaning up all state associated with the current configuration
1150 * so that the hardware is now fully quiesced.
1151 */
1152 usb_disable_device(udev, 0);
1153
3099e75a
GKH		 1154 usb_notify_remove_device(udev);
1155
1da177e4
LT		 1156 /* Free the device number, remove the /proc/bus/usb entry and
1157 * the sysfs attributes, and delete the parent's children[]
1158 * (or root_hub) pointer.
1159 */
1160 dev_dbg (&udev->dev, "unregistering device\n");
1161 release_address(udev);
1da177e4
LT		 1162 usb_remove_sysfs_dev_files(udev);
1163
1164 /* Avoid races with recursively_mark_NOTATTACHED() */
1165 spin_lock_irq(&device_state_lock);
1166 *pdev = NULL;
1167 spin_unlock_irq(&device_state_lock);
1168
9ad3d6cc 1169 usb_unlock_device(udev);
1da177e4
LT		 1170
1171 device_unregister(&udev->dev);
1172}
1173
55c52718
AS		 1174static inline const char *plural(int n)
1175{
1176 return (n == 1 ? "" : "s");
1177}
1178
1da177e4
LT		 1179static int choose_configuration(struct usb_device *udev)
1180{
55c52718 1181 int i;
55c52718 1182 int num_configs;
1fbe75e1 1183 int insufficient_power = 0;
55c52718
AS		 1184 struct usb_host_config *c, *best;
1185
55c52718
AS		 1186 best = NULL;
1187 c = udev->config;
1188 num_configs = udev->descriptor.bNumConfigurations;
1189 for (i = 0; i < num_configs; (i++, c++)) {
6aa35675
AS		 1190 struct usb_interface_descriptor *desc = NULL;
1191
1192 /* It's possible that a config has no interfaces! */
1193 if (c->desc.bNumInterfaces > 0)
1194 desc = &c->intf_cache[0]->altsetting->desc;
55c52718
AS		 1195
1196 /*
1197 * HP's USB bus-powered keyboard has only one configuration
1198 * and it claims to be self-powered; other devices may have
1199 * similar errors in their descriptors. If the next test
1200 * were allowed to execute, such configurations would always
1201 * be rejected and the devices would not work as expected.
436f5762
AS		 1202 * In the meantime, we run the risk of selecting a config
1203 * that requires external power at a time when that power
1204 * isn't available. It seems to be the lesser of two evils.
1205 *
1206 * Bugzilla #6448 reports a device that appears to crash
1207 * when it receives a GET_DEVICE_STATUS request! We don't
1208 * have any other way to tell whether a device is self-powered,
1209 * but since we don't use that information anywhere but here,
1210 * the call has been removed.
1211 *
1212 * Maybe the GET_DEVICE_STATUS call and the test below can
1213 * be reinstated when device firmwares become more reliable.
1214 * Don't hold your breath.
55c52718
AS		 1215 */
1216#if 0
1217 /* Rule out self-powered configs for a bus-powered device */
1218 if (bus_powered && (c->desc.bmAttributes &
1219 USB_CONFIG_ATT_SELFPOWER))
1220 continue;
1221#endif
1da177e4 1222
55c52718
AS		 1223 /*
1224 * The next test may not be as effective as it should be.
1225 * Some hubs have errors in their descriptor, claiming
1226 * to be self-powered when they are really bus-powered.
1227 * We will overestimate the amount of current such hubs
1228 * make available for each port.
1229 *
1230 * This is a fairly benign sort of failure. It won't
1231 * cause us to reject configurations that we should have
1232 * accepted.
1233 */
1da177e4 1234
55c52718 1235 /* Rule out configs that draw too much bus current */
1fbe75e1
DD		 1236 if (c->desc.bMaxPower * 2 > udev->bus_mA) {
1237 insufficient_power++;
55c52718 1238 continue;
1fbe75e1 1239 }
1da177e4 1240
55c52718
AS		 1241 /* If the first config's first interface is COMM/2/0xff
1242 * (MSFT RNDIS), rule it out unless Linux has host-side
1243 * RNDIS support. */
6aa35675
AS		 1244 if (i == 0 && desc
1245 && desc->bInterfaceClass == USB_CLASS_COMM
55c52718
AS		 1246 && desc->bInterfaceSubClass == 2
1247 && desc->bInterfaceProtocol == 0xff) {
3f8f4a18 1248#ifndef CONFIG_USB_NET_RNDIS_HOST
55c52718
AS		 1249 continue;
1250#else
1251 best = c;
1252#endif
1253 }
1254
1255 /* From the remaining configs, choose the first one whose
1256 * first interface is for a non-vendor-specific class.
1257 * Reason: Linux is more likely to have a class driver
1258 * than a vendor-specific driver. */
1259 else if (udev->descriptor.bDeviceClass !=
1260 USB_CLASS_VENDOR_SPEC &&
6aa35675
AS		 1261 (!desc || desc->bInterfaceClass !=
1262 USB_CLASS_VENDOR_SPEC)) {
55c52718 1263 best = c;
1da177e4
LT		 1264 break;
1265 }
55c52718
AS		 1266
1267 /* If all the remaining configs are vendor-specific,
1268 * choose the first one. */
1269 else if (!best)
1270 best = c;
1271 }
1272
1fbe75e1
DD		 1273 if (insufficient_power > 0)
1274 dev_info(&udev->dev, "rejected %d configuration%s "
1275 "due to insufficient available bus power\n",
1276 insufficient_power, plural(insufficient_power));
1277
55c52718
AS		 1278 if (best) {
1279 i = best->desc.bConfigurationValue;
1da177e4 1280 dev_info(&udev->dev,
55c52718
AS		 1281 "configuration #%d chosen from %d choice%s\n",
1282 i, num_configs, plural(num_configs));
1283 } else {
1284 i = -1;
1285 dev_warn(&udev->dev,
1286 "no configuration chosen from %d choice%s\n",
1287 num_configs, plural(num_configs));
1da177e4 1288 }
55c52718 1289 return i;
1da177e4
LT		 1290}
1291
1292#ifdef DEBUG
1293static void show_string(struct usb_device *udev, char *id, char *string)
1294{
1295 if (!string)
1296 return;
1297 dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1298}
1299
1300#else
1301static inline void show_string(struct usb_device *udev, char *id, char *string)
1302{}
1303#endif
1304
1da177e4
LT		 1305
1306#ifdef CONFIG_USB_OTG
1307#include "otg_whitelist.h"
1308#endif
1309
1310/**
1311 * usb_new_device - perform initial device setup (usbcore-internal)
1312 * @udev: newly addressed device (in ADDRESS state)
1313 *
1314 * This is called with devices which have been enumerated, but not yet
1315 * configured. The device descriptor is available, but not descriptors
9ad3d6cc
AS		 1316 * for any device configuration. The caller must have locked either
1317 * the parent hub (if udev is a normal device) or else the
1da177e4
LT		 1318 * usb_bus_list_lock (if udev is a root hub). The parent's pointer to
1319 * udev has already been installed, but udev is not yet visible through
1320 * sysfs or other filesystem code.
1321 *
1322 * Returns 0 for success (device is configured and listed, with its
1323 * interfaces, in sysfs); else a negative errno value.
1324 *
1325 * This call is synchronous, and may not be used in an interrupt context.
1326 *
9ad3d6cc 1327 * Only the hub driver or root-hub registrar should ever call this.
1da177e4
LT		 1328 */
1329int usb_new_device(struct usb_device *udev)
1330{
1331 int err;
1332 int c;
1333
1334 err = usb_get_configuration(udev);
1335 if (err < 0) {
1336 dev_err(&udev->dev, "can't read configurations, error %d\n",
1337 err);
1338 goto fail;
1339 }
1340
1341 /* read the standard strings and cache them if present */
4f62efe6
AS		 1342 udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1343 udev->manufacturer = usb_cache_string(udev,
1344 udev->descriptor.iManufacturer);
1345 udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1da177e4
LT		 1346
1347 /* Tell the world! */
1348 dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1349 "SerialNumber=%d\n",
1350 udev->descriptor.iManufacturer,
1351 udev->descriptor.iProduct,
1352 udev->descriptor.iSerialNumber);
1353 show_string(udev, "Product", udev->product);
1354 show_string(udev, "Manufacturer", udev->manufacturer);
1355 show_string(udev, "SerialNumber", udev->serial);
1356
1357#ifdef CONFIG_USB_OTG
1358 /*
1359 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1360 * to wake us after we've powered off VBUS; and HNP, switching roles
1361 * "host" to "peripheral". The OTG descriptor helps figure this out.
1362 */
1363 if (!udev->bus->is_b_host
1364 && udev->config
1365 && udev->parent == udev->bus->root_hub) {
1366 struct usb_otg_descriptor *desc = 0;
1367 struct usb_bus *bus = udev->bus;
1368
1369 /* descriptor may appear anywhere in config */
1370 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1371 le16_to_cpu(udev->config[0].desc.wTotalLength),
1372 USB_DT_OTG, (void **) &desc) == 0) {
1373 if (desc->bmAttributes & USB_OTG_HNP) {
12c3da34 1374 unsigned port1 = udev->portnum;
1da177e4
LT		 1375 struct usb_device *root = udev->parent;
1376
1da177e4
LT		 1377 dev_info(&udev->dev,
1378 "Dual-Role OTG device on %sHNP port\n",
1379 (port1 == bus->otg_port)
1380 ? "" : "non-");
1381
1382 /* enable HNP before suspend, it's simpler */
1383 if (port1 == bus->otg_port)
1384 bus->b_hnp_enable = 1;
1385 err = usb_control_msg(udev,
1386 usb_sndctrlpipe(udev, 0),
1387 USB_REQ_SET_FEATURE, 0,
1388 bus->b_hnp_enable
1389 ? USB_DEVICE_B_HNP_ENABLE
1390 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1391 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1392 if (err < 0) {
1393 /* OTG MESSAGE: report errors here,
1394 * customize to match your product.
1395 */
1396 dev_info(&udev->dev,
1397 "can't set HNP mode; %d\n",
1398 err);
1399 bus->b_hnp_enable = 0;
1400 }
1401 }
1402 }
1403 }
1404
1405 if (!is_targeted(udev)) {
1406
1407 /* Maybe it can talk to us, though we can't talk to it.
1408 * (Includes HNP test device.)
1409 */
1410 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
390a8c34
DB		 1411 static int __usb_suspend_device(struct usb_device *,
1412 int port1);
1413 err = __usb_suspend_device(udev, udev->bus->otg_port);
1da177e4
LT		 1414 if (err < 0)
1415 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1416 }
1417 err = -ENODEV;
1418 goto fail;
1419 }
1420#endif
1421
1422 /* put device-specific files into sysfs */
1423 err = device_add (&udev->dev);
1424 if (err) {
1425 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1426 goto fail;
1427 }
1428 usb_create_sysfs_dev_files (udev);
1429
9ad3d6cc
AS		 1430 usb_lock_device(udev);
1431
1da177e4
LT		 1432 /* choose and set the configuration. that registers the interfaces
1433 * with the driver core, and lets usb device drivers bind to them.
1434 */
1435 c = choose_configuration(udev);
55c52718 1436 if (c >= 0) {
1da177e4
LT		 1437 err = usb_set_configuration(udev, c);
1438 if (err) {
1439 dev_err(&udev->dev, "can't set config #%d, error %d\n",
1440 c, err);
55c52718
AS		 1441 /* This need not be fatal. The user can try to
1442 * set other configurations. */
1da177e4
LT		 1443 }
1444 }
1445
1446 /* USB device state == configured ... usable */
3099e75a 1447 usb_notify_add_device(udev);
1da177e4 1448
9ad3d6cc
AS		 1449 usb_unlock_device(udev);
1450
1da177e4
LT		 1451 return 0;
1452
1453fail:
1454 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1455 return err;
1456}
1457
1458
1459static int hub_port_status(struct usb_hub *hub, int port1,
1460 u16 *status, u16 *change)
1461{
1462 int ret;
1463
1464 ret = get_port_status(hub->hdev, port1, &hub->status->port);
1465 if (ret < 0)
1466 dev_err (hub->intfdev,
1467 "%s failed (err = %d)\n", __FUNCTION__, ret);
1468 else {
1469 *status = le16_to_cpu(hub->status->port.wPortStatus);
1470 *change = le16_to_cpu(hub->status->port.wPortChange);
1471 ret = 0;
1472 }
1473 return ret;
1474}
1475
1476#define PORT_RESET_TRIES 5
1477#define SET_ADDRESS_TRIES 2
1478#define GET_DESCRIPTOR_TRIES 2
1479#define SET_CONFIG_TRIES (2 * (use_both_schemes + 1))
1480#define USE_NEW_SCHEME(i) ((i) / 2 == old_scheme_first)
1481
1482#define HUB_ROOT_RESET_TIME 50 /* times are in msec */
1483#define HUB_SHORT_RESET_TIME 10
1484#define HUB_LONG_RESET_TIME 200
1485#define HUB_RESET_TIMEOUT 500
1486
1487static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1488 struct usb_device *udev, unsigned int delay)
1489{
1490 int delay_time, ret;
1491 u16 portstatus;
1492 u16 portchange;
1493
1494 for (delay_time = 0;
1495 delay_time < HUB_RESET_TIMEOUT;
1496 delay_time += delay) {
1497 /* wait to give the device a chance to reset */
1498 msleep(delay);
1499
1500 /* read and decode port status */
1501 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1502 if (ret < 0)
1503 return ret;
1504
1505 /* Device went away? */
1506 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1507 return -ENOTCONN;
1508
1509 /* bomb out completely if something weird happened */
1510 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1511 return -EINVAL;
1512
1513 /* if we`ve finished resetting, then break out of the loop */
1514 if (!(portstatus & USB_PORT_STAT_RESET) &&
1515 (portstatus & USB_PORT_STAT_ENABLE)) {
1516 if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1517 udev->speed = USB_SPEED_HIGH;
1518 else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1519 udev->speed = USB_SPEED_LOW;
1520 else
1521 udev->speed = USB_SPEED_FULL;
1522 return 0;
1523 }
1524
1525 /* switch to the long delay after two short delay failures */
1526 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1527 delay = HUB_LONG_RESET_TIME;
1528
1529 dev_dbg (hub->intfdev,
1530 "port %d not reset yet, waiting %dms\n",
1531 port1, delay);
1532 }
1533
1534 return -EBUSY;
1535}
1536
1537static int hub_port_reset(struct usb_hub *hub, int port1,
1538 struct usb_device *udev, unsigned int delay)
1539{
1540 int i, status;
1541
1542 /* Reset the port */
1543 for (i = 0; i < PORT_RESET_TRIES; i++) {
1544 status = set_port_feature(hub->hdev,
1545 port1, USB_PORT_FEAT_RESET);
1546 if (status)
1547 dev_err(hub->intfdev,
1548 "cannot reset port %d (err = %d)\n",
1549 port1, status);
1550 else {
1551 status = hub_port_wait_reset(hub, port1, udev, delay);
dd16525b 1552 if (status && status != -ENOTCONN)
1da177e4
LT		 1553 dev_dbg(hub->intfdev,
1554 "port_wait_reset: err = %d\n",
1555 status);
1556 }
1557
1558 /* return on disconnect or reset */
1559 switch (status) {
1560 case 0:
b789696a
DB		 1561 /* TRSTRCY = 10 ms; plus some extra */
1562 msleep(10 + 40);
1da177e4
LT		 1563 /* FALL THROUGH */
1564 case -ENOTCONN:
1565 case -ENODEV:
1566 clear_port_feature(hub->hdev,
1567 port1, USB_PORT_FEAT_C_RESET);
1568 /* FIXME need disconnect() for NOTATTACHED device */
1569 usb_set_device_state(udev, status
1570 ? USB_STATE_NOTATTACHED
1571 : USB_STATE_DEFAULT);
1572 return status;
1573 }
1574
1575 dev_dbg (hub->intfdev,
1576 "port %d not enabled, trying reset again...\n",
1577 port1);
1578 delay = HUB_LONG_RESET_TIME;
1579 }
1580
1581 dev_err (hub->intfdev,
1582 "Cannot enable port %i. Maybe the USB cable is bad?\n",
1583 port1);
1584
1585 return status;
1586}
1587
1da177e4
LT		 1588/*
1589 * Disable a port and mark a logical connnect-change event, so that some
1590 * time later khubd will disconnect() any existing usb_device on the port
1591 * and will re-enumerate if there actually is a device attached.
1592 */
1593static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1594{
1595 dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1596 hub_port_disable(hub, port1, 1);
1597
1598 /* FIXME let caller ask to power down the port:
1599 * - some devices won't enumerate without a VBUS power cycle
1600 * - SRP saves power that way
390a8c34 1601 * - ... new call, TBD ...
1da177e4
LT		 1602 * That's easy if this hub can switch power per-port, and
1603 * khubd reactivates the port later (timer, SRP, etc).
1604 * Powerdown must be optional, because of reset/DFU.
1605 */
1606
1607 set_bit(port1, hub->change_bits);
1608 kick_khubd(hub);
1609}
1610
1611
1612#ifdef CONFIG_USB_SUSPEND
1613
1614/*
1615 * Selective port suspend reduces power; most suspended devices draw
1616 * less than 500 uA. It's also used in OTG, along with remote wakeup.
1617 * All devices below the suspended port are also suspended.
1618 *
1619 * Devices leave suspend state when the host wakes them up. Some devices
1620 * also support "remote wakeup", where the device can activate the USB
1621 * tree above them to deliver data, such as a keypress or packet. In
1622 * some cases, this wakes the USB host.
1623 */
1624static int hub_port_suspend(struct usb_hub *hub, int port1,
1625 struct usb_device *udev)
1626{
1627 int status;
1628
1629 // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1630
1631 /* enable remote wakeup when appropriate; this lets the device
1632 * wake up the upstream hub (including maybe the root hub).
1633 *
1634 * NOTE: OTG devices may issue remote wakeup (or SRP) even when
1635 * we don't explicitly enable it here.
1636 */
b94dc6b5 1637 if (device_may_wakeup(&udev->dev)) {
1da177e4
LT		 1638 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1639 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1640 USB_DEVICE_REMOTE_WAKEUP, 0,
1641 NULL, 0,
1642 USB_CTRL_SET_TIMEOUT);
1643 if (status)
1644 dev_dbg(&udev->dev,
1645 "won't remote wakeup, status %d\n",
1646 status);
1647 }
1648
1649 /* see 7.1.7.6 */
1650 status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1651 if (status) {
1652 dev_dbg(hub->intfdev,
1653 "can't suspend port %d, status %d\n",
1654 port1, status);
1655 /* paranoia: "should not happen" */
1656 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1657 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1658 USB_DEVICE_REMOTE_WAKEUP, 0,
1659 NULL, 0,
1660 USB_CTRL_SET_TIMEOUT);
1661 } else {
1662 /* device has up to 10 msec to fully suspend */
1663 dev_dbg(&udev->dev, "usb suspend\n");
1664 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1665 msleep(10);
1666 }
1667 return status;
1668}
1669
1670/*
1671 * Devices on USB hub ports have only one "suspend" state, corresponding
ba9d35fb 1672 * to ACPI D2, "may cause the device to lose some context".
1da177e4
LT		 1673 * State transitions include:
1674 *
1675 * - suspend, resume ... when the VBUS power link stays live
1676 * - suspend, disconnect ... VBUS lost
1677 *
1678 * Once VBUS drop breaks the circuit, the port it's using has to go through
1679 * normal re-enumeration procedures, starting with enabling VBUS power.
1680 * Other than re-initializing the hub (plug/unplug, except for root hubs),
1681 * Linux (2.6) currently has NO mechanisms to initiate that: no khubd
1682 * timer, no SRP, no requests through sysfs.
390a8c34
DB		 1683 *
1684 * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1685 * the root hub for their bus goes into global suspend ... so we don't
1686 * (falsely) update the device power state to say it suspended.
1da177e4 1687 */
390a8c34 1688static int __usb_suspend_device (struct usb_device *udev, int port1)
1da177e4 1689{
f3f3253d 1690 int status = 0;
1da177e4
LT		 1691
1692 /* caller owns the udev device lock */
1693 if (port1 < 0)
1694 return port1;
1695
1696 if (udev->state == USB_STATE_SUSPENDED
1697 || udev->state == USB_STATE_NOTATTACHED) {
1698 return 0;
1699 }
1700
c9f89fa4 1701 /* all interfaces must already be suspended */
1da177e4
LT		 1702 if (udev->actconfig) {
1703 int i;
1704
1705 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1706 struct usb_interface *intf;
1da177e4
LT		 1707
1708 intf = udev->actconfig->interface[i];
c9f89fa4
DB		 1709 if (is_active(intf)) {
1710 dev_dbg(&intf->dev, "nyet suspended\n");
1711 return -EBUSY;
1da177e4
LT		 1712 }
1713 }
1714 }
1715
f3f3253d
DB		 1716 /* we only change a device's upstream USB link.
1717 * root hubs have no upstream USB link.
1da177e4 1718 */
f3f3253d 1719 if (udev->parent)
1da177e4
LT		 1720 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1721 udev);
1722
1723 if (status == 0)
390a8c34 1724 udev->dev.power.power_state = PMSG_SUSPEND;
1da177e4
LT		 1725 return status;
1726}
1727
f3f3253d
DB		 1728#endif
1729
5edbfb7c 1730/*
1da177e4
LT		 1731 * usb_suspend_device - suspend a usb device
1732 * @udev: device that's no longer in active use
5edbfb7c 1733 * Context: must be able to sleep; device not locked; pm locks held
1da177e4
LT		 1734 *
1735 * Suspends a USB device that isn't in active use, conserving power.
1736 * Devices may wake out of a suspend, if anything important happens,
1737 * using the remote wakeup mechanism. They may also be taken out of
1738 * suspend by the host, using usb_resume_device(). It's also routine
1739 * to disconnect devices while they are suspended.
1740 *
390a8c34
DB		 1741 * This only affects the USB hardware for a device; its interfaces
1742 * (and, for hubs, child devices) must already have been suspended.
1743 *
1da177e4
LT		 1744 * Suspending OTG devices may trigger HNP, if that's been enabled
1745 * between a pair of dual-role devices. That will change roles, such
1746 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1747 *
1748 * Returns 0 on success, else negative errno.
1749 */
390a8c34 1750int usb_suspend_device(struct usb_device *udev)
1da177e4 1751{
f3f3253d 1752#ifdef CONFIG_USB_SUSPEND
4bf0ba86
AS		 1753 if (udev->state == USB_STATE_NOTATTACHED)
1754 return -ENODEV;
12c3da34 1755 return __usb_suspend_device(udev, udev->portnum);
f3f3253d
DB		 1756#else
1757 /* NOTE: udev->state unchanged, it's not lying ... */
1758 udev->dev.power.power_state = PMSG_SUSPEND;
1759 return 0;
1760#endif
1da177e4 1761}
f3f3253d 1762
1da177e4 1763/*
390a8c34
DB		 1764 * If the USB "suspend" state is in use (rather than "global suspend"),
1765 * many devices will be individually taken out of suspend state using
1766 * special" resume" signaling. These routines kick in shortly after
1da177e4
LT		 1767 * hardware resume signaling is finished, either because of selective
1768 * resume (by host) or remote wakeup (by device) ... now see what changed
1769 * in the tree that's rooted at this device.
1770 */
f3f3253d 1771static int finish_device_resume(struct usb_device *udev)
1da177e4
LT		 1772{
1773 int status;
1774 u16 devstatus;
1775
1776 /* caller owns the udev device lock */
f3f3253d 1777 dev_dbg(&udev->dev, "finish resume\n");
1da177e4
LT		 1778
1779 /* usb ch9 identifies four variants of SUSPENDED, based on what
1780 * state the device resumes to. Linux currently won't see the
1781 * first two on the host side; they'd be inside hub_port_init()
1782 * during many timeouts, but khubd can't suspend until later.
1783 */
1784 usb_set_device_state(udev, udev->actconfig
1785 ? USB_STATE_CONFIGURED
1786 : USB_STATE_ADDRESS);
4bf0ba86 1787 udev->dev.power.power_state = PMSG_ON;
1da177e4
LT		 1788
1789 /* 10.5.4.5 says be sure devices in the tree are still there.
1790 * For now let's assume the device didn't go crazy on resume,
1791 * and device drivers will know about any resume quirks.
1792 */
1793 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
55c52718 1794 if (status < 2)
1da177e4
LT		 1795 dev_dbg(&udev->dev,
1796 "gone after usb resume? status %d\n",
1797 status);
1798 else if (udev->actconfig) {
1799 unsigned i;
dbc3887e 1800 int (*resume)(struct device *);
1da177e4
LT		 1801
1802 le16_to_cpus(&devstatus);
55c52718 1803 if ((devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
f3f3253d 1804 && udev->parent) {
1da177e4
LT		 1805 status = usb_control_msg(udev,
1806 usb_sndctrlpipe(udev, 0),
1807 USB_REQ_CLEAR_FEATURE,
1808 USB_RECIP_DEVICE,
1809 USB_DEVICE_REMOTE_WAKEUP, 0,
1810 NULL, 0,
1811 USB_CTRL_SET_TIMEOUT);
1812 if (status) {
1813 dev_dbg(&udev->dev, "disable remote "
1814 "wakeup, status %d\n", status);
1815 status = 0;
1816 }
1817 }
1818
1819 /* resume interface drivers; if this is a hub, it
dbc3887e 1820 * may have a child resume event to deal with soon
1da177e4 1821 */
dbc3887e 1822 resume = udev->dev.bus->resume;
4bf0ba86
AS		 1823 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1824 struct device *dev =
1825 &udev->actconfig->interface[i]->dev;
1826
1827 down(&dev->sem);
1828 (void) resume(dev);
1829 up(&dev->sem);
1830 }
1da177e4
LT		 1831 status = 0;
1832
1833 } else if (udev->devnum <= 0) {
1834 dev_dbg(&udev->dev, "bogus resume!\n");
1835 status = -EINVAL;
1836 }
1837 return status;
1838}
1839
f3f3253d
DB		 1840#ifdef CONFIG_USB_SUSPEND
1841
1da177e4
LT		 1842static int
1843hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1844{
1845 int status;
1846
1847 // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1848
1849 /* see 7.1.7.7; affects power usage, but not budgeting */
1850 status = clear_port_feature(hub->hdev,
1851 port1, USB_PORT_FEAT_SUSPEND);
1852 if (status) {
1853 dev_dbg(hub->intfdev,
1854 "can't resume port %d, status %d\n",
1855 port1, status);
1856 } else {
1857 u16 devstatus;
1858 u16 portchange;
1859
1860 /* drive resume for at least 20 msec */
1861 if (udev)
1862 dev_dbg(&udev->dev, "RESUME\n");
1863 msleep(25);
1864
1865#define LIVE_FLAGS ( USB_PORT_STAT_POWER \
1866 | USB_PORT_STAT_ENABLE \
1867 | USB_PORT_STAT_CONNECTION)
1868
1869 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1870 * stop resume signaling. Then finish the resume
1871 * sequence.
1872 */
1873 devstatus = portchange = 0;
1874 status = hub_port_status(hub, port1,
1875 &devstatus, &portchange);
1876 if (status < 0
1877 || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
1878 || (devstatus & USB_PORT_STAT_SUSPEND) != 0
1879 ) {
1880 dev_dbg(hub->intfdev,
1881 "port %d status %04x.%04x after resume, %d\n",
1882 port1, portchange, devstatus, status);
1883 } else {
1884 /* TRSMRCY = 10 msec */
1885 msleep(10);
1886 if (udev)
f3f3253d 1887 status = finish_device_resume(udev);
1da177e4
LT		 1888 }
1889 }
1890 if (status < 0)
1891 hub_port_logical_disconnect(hub, port1);
1892
1893 return status;
1894}
1895
f3f3253d 1896#endif
1da177e4 1897
5edbfb7c 1898/*
1da177e4
LT		 1899 * usb_resume_device - re-activate a suspended usb device
1900 * @udev: device to re-activate
5edbfb7c 1901 * Context: must be able to sleep; device not locked; pm locks held
1da177e4
LT		 1902 *
1903 * This will re-activate the suspended device, increasing power usage
1904 * while letting drivers communicate again with its endpoints.
1905 * USB resume explicitly guarantees that the power session between
1906 * the host and the device is the same as it was when the device
1907 * suspended.
1908 *
1909 * Returns 0 on success, else negative errno.
1910 */
1911int usb_resume_device(struct usb_device *udev)
1912{
12c3da34 1913 int status;
1da177e4 1914
4bf0ba86
AS		 1915 if (udev->state == USB_STATE_NOTATTACHED)
1916 return -ENODEV;
1da177e4 1917
f3f3253d
DB		 1918 /* selective resume of one downstream hub-to-device port */
1919 if (udev->parent) {
fb669cc0 1920#ifdef CONFIG_USB_SUSPEND
f3f3253d
DB		 1921 if (udev->state == USB_STATE_SUSPENDED) {
1922 // NOTE swsusp may bork us, device state being wrong...
1923 // NOTE this fails if parent is also suspended...
1924 status = hub_port_resume(hdev_to_hub(udev->parent),
12c3da34 1925 udev->portnum, udev);
1da177e4 1926 } else
f3f3253d 1927#endif
43c5d5aa 1928 status = 0;
fb669cc0 1929 } else
f3f3253d
DB		 1930 status = finish_device_resume(udev);
1931 if (status < 0)
1da177e4
LT		 1932 dev_dbg(&udev->dev, "can't resume, status %d\n",
1933 status);
1da177e4 1934
1da177e4 1935 /* rebind drivers that had no suspend() */
4bf0ba86
AS		 1936 if (status == 0) {
1937 usb_unlock_device(udev);
1da177e4 1938 bus_rescan_devices(&usb_bus_type);
4bf0ba86
AS		 1939 usb_lock_device(udev);
1940 }
1da177e4
LT		 1941 return status;
1942}
1943
1944static int remote_wakeup(struct usb_device *udev)
1945{
1946 int status = 0;
1947
f3f3253d
DB		 1948#ifdef CONFIG_USB_SUSPEND
1949
1da177e4
LT		 1950 /* don't repeat RESUME sequence if this device
1951 * was already woken up by some other task
1952 */
9ad3d6cc 1953 usb_lock_device(udev);
1da177e4
LT		 1954 if (udev->state == USB_STATE_SUSPENDED) {
1955 dev_dbg(&udev->dev, "RESUME (wakeup)\n");
1956 /* TRSMRCY = 10 msec */
1957 msleep(10);
f3f3253d 1958 status = finish_device_resume(udev);
1da177e4 1959 }
9ad3d6cc 1960 usb_unlock_device(udev);
f3f3253d 1961#endif
1da177e4
LT		 1962 return status;
1963}
1964
db690874 1965static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
1da177e4
LT		 1966{
1967 struct usb_hub *hub = usb_get_intfdata (intf);
1968 struct usb_device *hdev = hub->hdev;
1969 unsigned port1;
1da177e4 1970
c9f89fa4 1971 /* fail if children aren't already suspended */
1da177e4
LT		 1972 for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1973 struct usb_device *udev;
1974
1975 udev = hdev->children [port1-1];
f3f3253d
DB		 1976 if (udev && (udev->dev.power.power_state.event
1977 == PM_EVENT_ON
1978#ifdef CONFIG_USB_SUSPEND
1979 || udev->state != USB_STATE_SUSPENDED
1980#endif
1981 )) {
c9f89fa4
DB		 1982 dev_dbg(&intf->dev, "port %d nyet suspended\n", port1);
1983 return -EBUSY;
1984 }
1da177e4
LT		 1985 }
1986
f3f3253d
DB		 1987 /* "global suspend" of the downstream HC-to-USB interface */
1988 if (!hdev->parent) {
1989 struct usb_bus *bus = hdev->bus;
0c0382e3
AS		 1990 if (bus) {
1991 int status = hcd_bus_suspend (bus);
f3f3253d
DB		 1992
1993 if (status != 0) {
1994 dev_dbg(&hdev->dev, "'global' suspend %d\n",
1995 status);
1996 return status;
1997 }
1998 } else
1999 return -EOPNOTSUPP;
2000 }
2001
c9f89fa4
DB		 2002 /* stop khubd and related activity */
2003 hub_quiesce(hub);
1da177e4
LT		 2004 return 0;
2005}
2006
2007static int hub_resume(struct usb_interface *intf)
2008{
2009 struct usb_device *hdev = interface_to_usbdev(intf);
2010 struct usb_hub *hub = usb_get_intfdata (intf);
1da177e4
LT		 2011 int status;
2012
f3f3253d
DB		 2013 /* "global resume" of the downstream HC-to-USB interface */
2014 if (!hdev->parent) {
2015 struct usb_bus *bus = hdev->bus;
0c0382e3
AS		 2016 if (bus) {
2017 status = hcd_bus_resume (bus);
f3f3253d
DB		 2018 if (status) {
2019 dev_dbg(&intf->dev, "'global' resume %d\n",
2020 status);
2021 return status;
2022 }
2023 } else
2024 return -EOPNOTSUPP;
2025 if (status == 0) {
2026 /* TRSMRCY = 10 msec */
2027 msleep(10);
2028 }
2029 }
2030
2031 hub_activate(hub);
2032
2033 /* REVISIT: this recursion probably shouldn't exist. Remove
2034 * this code sometime, after retesting with different root and
2035 * external hubs.
2036 */
2037#ifdef CONFIG_USB_SUSPEND
2038 {
2039 unsigned port1;
2040
1da177e4
LT		 2041 for (port1 = 1; port1 <= hdev->maxchild; port1++) {
2042 struct usb_device *udev;
2043 u16 portstat, portchange;
2044
2045 udev = hdev->children [port1-1];
2046 status = hub_port_status(hub, port1, &portstat, &portchange);
2047 if (status == 0) {
2048 if (portchange & USB_PORT_STAT_C_SUSPEND) {
2049 clear_port_feature(hdev, port1,
2050 USB_PORT_FEAT_C_SUSPEND);
2051 portchange &= ~USB_PORT_STAT_C_SUSPEND;
2052 }
2053
2054 /* let khubd handle disconnects etc */
2055 if (portchange)
2056 continue;
2057 }
2058
2059 if (!udev || status < 0)
2060 continue;
9ad3d6cc 2061 usb_lock_device(udev);
1da177e4
LT		 2062 if (portstat & USB_PORT_STAT_SUSPEND)
2063 status = hub_port_resume(hub, port1, udev);
2064 else {
f3f3253d 2065 status = finish_device_resume(udev);
1da177e4
LT		 2066 if (status < 0) {
2067 dev_dbg(&intf->dev, "resume port %d --> %d\n",
2068 port1, status);
2069 hub_port_logical_disconnect(hub, port1);
2070 }
2071 }
9ad3d6cc 2072 usb_unlock_device(udev);
1da177e4 2073 }
f3f3253d
DB		 2074 }
2075#endif
1da177e4
LT		 2076 return 0;
2077}
2078
979d5199
DB		 2079void usb_suspend_root_hub(struct usb_device *hdev)
2080{
2081 struct usb_hub *hub = hdev_to_hub(hdev);
2082
2083 /* This also makes any led blinker stop retriggering. We're called
2084 * from irq, so the blinker might still be scheduled. Caller promises
2085 * that the root hub status URB will be canceled.
2086 */
2087 __hub_quiesce(hub);
2088 mark_quiesced(to_usb_interface(hub->intfdev));
2089}
2090
1da177e4
LT		 2091void usb_resume_root_hub(struct usb_device *hdev)
2092{
2093 struct usb_hub *hub = hdev_to_hub(hdev);
2094
2095 hub->resume_root_hub = 1;
2096 kick_khubd(hub);
2097}
2098
1da177e4
LT		 2099
2100/* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2101 *
2102 * Between connect detection and reset signaling there must be a delay
2103 * of 100ms at least for debounce and power-settling. The corresponding
2104 * timer shall restart whenever the downstream port detects a disconnect.
2105 *
2106 * Apparently there are some bluetooth and irda-dongles and a number of
2107 * low-speed devices for which this debounce period may last over a second.
2108 * Not covered by the spec - but easy to deal with.
2109 *
2110 * This implementation uses a 1500ms total debounce timeout; if the
2111 * connection isn't stable by then it returns -ETIMEDOUT. It checks
2112 * every 25ms for transient disconnects. When the port status has been
2113 * unchanged for 100ms it returns the port status.
2114 */
2115
2116#define HUB_DEBOUNCE_TIMEOUT 1500
2117#define HUB_DEBOUNCE_STEP 25
2118#define HUB_DEBOUNCE_STABLE 100
2119
2120static int hub_port_debounce(struct usb_hub *hub, int port1)
2121{
2122 int ret;
2123 int total_time, stable_time = 0;
2124 u16 portchange, portstatus;
2125 unsigned connection = 0xffff;
2126
2127 for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2128 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2129 if (ret < 0)
2130 return ret;
2131
2132 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2133 (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2134 stable_time += HUB_DEBOUNCE_STEP;
2135 if (stable_time >= HUB_DEBOUNCE_STABLE)
2136 break;
2137 } else {
2138 stable_time = 0;
2139 connection = portstatus & USB_PORT_STAT_CONNECTION;
2140 }
2141
2142 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2143 clear_port_feature(hub->hdev, port1,
2144 USB_PORT_FEAT_C_CONNECTION);
2145 }
2146
2147 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2148 break;
2149 msleep(HUB_DEBOUNCE_STEP);
2150 }
2151
2152 dev_dbg (hub->intfdev,
2153 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2154 port1, total_time, stable_time, portstatus);
2155
2156 if (stable_time < HUB_DEBOUNCE_STABLE)
2157 return -ETIMEDOUT;
2158 return portstatus;
2159}
2160
2161static void ep0_reinit(struct usb_device *udev)
2162{
2163 usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2164 usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2165 udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2166}
2167
2168#define usb_sndaddr0pipe() (PIPE_CONTROL << 30)
2169#define usb_rcvaddr0pipe() ((PIPE_CONTROL << 30) | USB_DIR_IN)
2170
2171static int hub_set_address(struct usb_device *udev)
2172{
2173 int retval;
2174
2175 if (udev->devnum == 0)
2176 return -EINVAL;
2177 if (udev->state == USB_STATE_ADDRESS)
2178 return 0;
2179 if (udev->state != USB_STATE_DEFAULT)
2180 return -EINVAL;
2181 retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2182 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2183 NULL, 0, USB_CTRL_SET_TIMEOUT);
2184 if (retval == 0) {
2185 usb_set_device_state(udev, USB_STATE_ADDRESS);
2186 ep0_reinit(udev);
2187 }
2188 return retval;
2189}
2190
2191/* Reset device, (re)assign address, get device descriptor.
2192 * Device connection must be stable, no more debouncing needed.
2193 * Returns device in USB_STATE_ADDRESS, except on error.
2194 *
2195 * If this is called for an already-existing device (as part of
2196 * usb_reset_device), the caller must own the device lock. For a
2197 * newly detected device that is not accessible through any global
2198 * pointers, it's not necessary to lock the device.
2199 */
2200static int
2201hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2202 int retry_counter)
2203{
4186ecf8 2204 static DEFINE_MUTEX(usb_address0_mutex);
1da177e4
LT		 2205
2206 struct usb_device *hdev = hub->hdev;
2207 int i, j, retval;
2208 unsigned delay = HUB_SHORT_RESET_TIME;
2209 enum usb_device_speed oldspeed = udev->speed;
2210
2211 /* root hub ports have a slightly longer reset period
2212 * (from USB 2.0 spec, section 7.1.7.5)
2213 */
2214 if (!hdev->parent) {
2215 delay = HUB_ROOT_RESET_TIME;
2216 if (port1 == hdev->bus->otg_port)
2217 hdev->bus->b_hnp_enable = 0;
2218 }
2219
2220 /* Some low speed devices have problems with the quick delay, so */
2221 /* be a bit pessimistic with those devices. RHbug #23670 */
2222 if (oldspeed == USB_SPEED_LOW)
2223 delay = HUB_LONG_RESET_TIME;
2224
4186ecf8 2225 mutex_lock(&usb_address0_mutex);
1da177e4
LT		 2226
2227 /* Reset the device; full speed may morph to high speed */
2228 retval = hub_port_reset(hub, port1, udev, delay);
2229 if (retval < 0) /* error or disconnect */
2230 goto fail;
2231 /* success, speed is known */
2232 retval = -ENODEV;
2233
2234 if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2235 dev_dbg(&udev->dev, "device reset changed speed!\n");
2236 goto fail;
2237 }
2238 oldspeed = udev->speed;
2239
2240 /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2241 * it's fixed size except for full speed devices.
2242 */
2243 switch (udev->speed) {
2244 case USB_SPEED_HIGH: /* fixed at 64 */
2245 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2246 break;
2247 case USB_SPEED_FULL: /* 8, 16, 32, or 64 */
2248 /* to determine the ep0 maxpacket size, try to read
2249 * the device descriptor to get bMaxPacketSize0 and
2250 * then correct our initial guess.
2251 */
2252 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2253 break;
2254 case USB_SPEED_LOW: /* fixed at 8 */
2255 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2256 break;
2257 default:
2258 goto fail;
2259 }
2260
2261 dev_info (&udev->dev,
2262 "%s %s speed USB device using %s and address %d\n",
2263 (udev->config) ? "reset" : "new",
2264 ({ char *speed; switch (udev->speed) {
2265 case USB_SPEED_LOW: speed = "low"; break;
2266 case USB_SPEED_FULL: speed = "full"; break;
2267 case USB_SPEED_HIGH: speed = "high"; break;
2268 default: speed = "?"; break;
2269 }; speed;}),
2270 udev->bus->controller->driver->name,
2271 udev->devnum);
2272
2273 /* Set up TT records, if needed */
2274 if (hdev->tt) {
2275 udev->tt = hdev->tt;
2276 udev->ttport = hdev->ttport;
2277 } else if (udev->speed != USB_SPEED_HIGH
2278 && hdev->speed == USB_SPEED_HIGH) {
2279 udev->tt = &hub->tt;
2280 udev->ttport = port1;
2281 }
2282
2283 /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2284 * Because device hardware and firmware is sometimes buggy in
2285 * this area, and this is how Linux has done it for ages.
2286 * Change it cautiously.
2287 *
2288 * NOTE: If USE_NEW_SCHEME() is true we will start by issuing
2289 * a 64-byte GET_DESCRIPTOR request. This is what Windows does,
2290 * so it may help with some non-standards-compliant devices.
2291 * Otherwise we start with SET_ADDRESS and then try to read the
2292 * first 8 bytes of the device descriptor to get the ep0 maxpacket
2293 * value.
2294 */
2295 for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2296 if (USE_NEW_SCHEME(retry_counter)) {
2297 struct usb_device_descriptor *buf;
2298 int r = 0;
2299
2300#define GET_DESCRIPTOR_BUFSIZE 64
2301 buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2302 if (!buf) {
2303 retval = -ENOMEM;
2304 continue;
2305 }
2306
2307 /* Use a short timeout the first time through,
2308 * so that recalcitrant full-speed devices with
2309 * 8- or 16-byte ep0-maxpackets won't slow things
2310 * down tremendously by NAKing the unexpectedly
2311 * early status stage. Also, retry on all errors;
2312 * some devices are flakey.
2313 */
2314 for (j = 0; j < 3; ++j) {
2315 buf->bMaxPacketSize0 = 0;
2316 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2317 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2318 USB_DT_DEVICE << 8, 0,
2319 buf, GET_DESCRIPTOR_BUFSIZE,
2320 (i ? USB_CTRL_GET_TIMEOUT : 1000));
2321 switch (buf->bMaxPacketSize0) {
2322 case 8: case 16: case 32: case 64:
2323 if (buf->bDescriptorType ==
2324 USB_DT_DEVICE) {
2325 r = 0;
2326 break;
2327 }
2328 /* FALL THROUGH */
2329 default:
2330 if (r == 0)
2331 r = -EPROTO;
2332 break;
2333 }
2334 if (r == 0)
2335 break;
2336 }
2337 udev->descriptor.bMaxPacketSize0 =
2338 buf->bMaxPacketSize0;
2339 kfree(buf);
2340
2341 retval = hub_port_reset(hub, port1, udev, delay);
2342 if (retval < 0) /* error or disconnect */
2343 goto fail;
2344 if (oldspeed != udev->speed) {
2345 dev_dbg(&udev->dev,
2346 "device reset changed speed!\n");
2347 retval = -ENODEV;
2348 goto fail;
2349 }
2350 if (r) {
2351 dev_err(&udev->dev, "device descriptor "
2352 "read/%s, error %d\n",
2353 "64", r);
2354 retval = -EMSGSIZE;
2355 continue;
2356 }
2357#undef GET_DESCRIPTOR_BUFSIZE
2358 }
2359
2360 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2361 retval = hub_set_address(udev);
2362 if (retval >= 0)
2363 break;
2364 msleep(200);
2365 }
2366 if (retval < 0) {
2367 dev_err(&udev->dev,
2368 "device not accepting address %d, error %d\n",
2369 udev->devnum, retval);
2370 goto fail;
2371 }
2372
2373 /* cope with hardware quirkiness:
2374 * - let SET_ADDRESS settle, some device hardware wants it
2375 * - read ep0 maxpacket even for high and low speed,
2376 */
2377 msleep(10);
2378 if (USE_NEW_SCHEME(retry_counter))
2379 break;
2380
2381 retval = usb_get_device_descriptor(udev, 8);
2382 if (retval < 8) {
2383 dev_err(&udev->dev, "device descriptor "
2384 "read/%s, error %d\n",
2385 "8", retval);
2386 if (retval >= 0)
2387 retval = -EMSGSIZE;
2388 } else {
2389 retval = 0;
2390 break;
2391 }
2392 }
2393 if (retval)
2394 goto fail;
2395
2396 i = udev->descriptor.bMaxPacketSize0;
2397 if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2398 if (udev->speed != USB_SPEED_FULL ||
2399 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2400 dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2401 retval = -EMSGSIZE;
2402 goto fail;
2403 }
2404 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2405 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2406 ep0_reinit(udev);
2407 }
2408
2409 retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2410 if (retval < (signed)sizeof(udev->descriptor)) {
2411 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2412 "all", retval);
2413 if (retval >= 0)
2414 retval = -ENOMSG;
2415 goto fail;
2416 }
2417
2418 retval = 0;
2419
2420fail:
2421 if (retval)
2422 hub_port_disable(hub, port1, 0);
4186ecf8 2423 mutex_unlock(&usb_address0_mutex);
1da177e4
LT		 2424 return retval;
2425}
2426
2427static void
2428check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2429{
2430 struct usb_qualifier_descriptor *qual;
2431 int status;
2432
2433 qual = kmalloc (sizeof *qual, SLAB_KERNEL);
2434 if (qual == NULL)
2435 return;
2436
2437 status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2438 qual, sizeof *qual);
2439 if (status == sizeof *qual) {
2440 dev_info(&udev->dev, "not running at top speed; "
2441 "connect to a high speed hub\n");
2442 /* hub LEDs are probably harder to miss than syslog */
2443 if (hub->has_indicators) {
2444 hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2445 schedule_work (&hub->leds);
2446 }
2447 }
1bc3c9e1 2448 kfree(qual);
1da177e4
LT		 2449}
2450
2451static unsigned
2452hub_power_remaining (struct usb_hub *hub)
2453{
2454 struct usb_device *hdev = hub->hdev;
2455 int remaining;
55c52718 2456 int port1;
1da177e4 2457
55c52718 2458 if (!hub->limited_power)
1da177e4
LT		 2459 return 0;
2460
55c52718
AS		 2461 remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
2462 for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
2463 struct usb_device *udev = hdev->children[port1 - 1];
2464 int delta;
1da177e4
LT		 2465
2466 if (!udev)
2467 continue;
2468
55c52718
AS		 2469 /* Unconfigured devices may not use more than 100mA,
2470 * or 8mA for OTG ports */
1da177e4 2471 if (udev->actconfig)
55c52718
AS		 2472 delta = udev->actconfig->desc.bMaxPower * 2;
2473 else if (port1 != udev->bus->otg_port || hdev->parent)
2474 delta = 100;
1da177e4 2475 else
55c52718
AS		 2476 delta = 8;
2477 if (delta > hub->mA_per_port)
2478 dev_warn(&udev->dev, "%dmA is over %umA budget "
2479 "for port %d!\n",
2480 delta, hub->mA_per_port, port1);
1da177e4
LT		 2481 remaining -= delta;
2482 }
2483 if (remaining < 0) {
55c52718
AS		 2484 dev_warn(hub->intfdev, "%dmA over power budget!\n",
2485 - remaining);
1da177e4
LT		 2486 remaining = 0;
2487 }
2488 return remaining;
2489}
2490
2491/* Handle physical or logical connection change events.
2492 * This routine is called when:
2493 * a port connection-change occurs;
2494 * a port enable-change occurs (often caused by EMI);
2495 * usb_reset_device() encounters changed descriptors (as from
2496 * a firmware download)
2497 * caller already locked the hub
2498 */
2499static void hub_port_connect_change(struct usb_hub *hub, int port1,
2500 u16 portstatus, u16 portchange)
2501{
2502 struct usb_device *hdev = hub->hdev;
2503 struct device *hub_dev = hub->intfdev;
74ad9bd2 2504 u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
1da177e4
LT		 2505 int status, i;
2506
2507 dev_dbg (hub_dev,
2508 "port %d, status %04x, change %04x, %s\n",
2509 port1, portstatus, portchange, portspeed (portstatus));
2510
2511 if (hub->has_indicators) {
2512 set_port_led(hub, port1, HUB_LED_AUTO);
2513 hub->indicator[port1-1] = INDICATOR_AUTO;
2514 }
2515
2516 /* Disconnect any existing devices under this port */
2517 if (hdev->children[port1-1])
2518 usb_disconnect(&hdev->children[port1-1]);
2519 clear_bit(port1, hub->change_bits);
2520
2521#ifdef CONFIG_USB_OTG
2522 /* during HNP, don't repeat the debounce */
2523 if (hdev->bus->is_b_host)
2524 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2525#endif
2526
2527 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2528 status = hub_port_debounce(hub, port1);
2529 if (status < 0) {
2530 dev_err (hub_dev,
2531 "connect-debounce failed, port %d disabled\n",
2532 port1);
2533 goto done;
2534 }
2535 portstatus = status;
2536 }
2537
2538 /* Return now if nothing is connected */
2539 if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2540
2541 /* maybe switch power back on (e.g. root hub was reset) */
74ad9bd2 2542 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
1da177e4
LT		 2543 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2544 set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2545
2546 if (portstatus & USB_PORT_STAT_ENABLE)
2547 goto done;
2548 return;
2549 }
2550
2551#ifdef CONFIG_USB_SUSPEND
2552 /* If something is connected, but the port is suspended, wake it up. */
2553 if (portstatus & USB_PORT_STAT_SUSPEND) {
2554 status = hub_port_resume(hub, port1, NULL);
2555 if (status < 0) {
2556 dev_dbg(hub_dev,
2557 "can't clear suspend on port %d; %d\n",
2558 port1, status);
2559 goto done;
2560 }
2561 }
2562#endif
2563
2564 for (i = 0; i < SET_CONFIG_TRIES; i++) {
2565 struct usb_device *udev;
2566
2567 /* reallocate for each attempt, since references
2568 * to the previous one can escape in various ways
2569 */
2570 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2571 if (!udev) {
2572 dev_err (hub_dev,
2573 "couldn't allocate port %d usb_device\n",
2574 port1);
2575 goto done;
2576 }
2577
2578 usb_set_device_state(udev, USB_STATE_POWERED);
2579 udev->speed = USB_SPEED_UNKNOWN;
55c52718
AS		 2580 udev->bus_mA = hub->mA_per_port;
2581
1da177e4
LT		 2582 /* set the address */
2583 choose_address(udev);
2584 if (udev->devnum <= 0) {
2585 status = -ENOTCONN; /* Don't retry */
2586 goto loop;
2587 }
2588
2589 /* reset and get descriptor */
2590 status = hub_port_init(hub, udev, port1, i);
2591 if (status < 0)
2592 goto loop;
2593
2594 /* consecutive bus-powered hubs aren't reliable; they can
2595 * violate the voltage drop budget. if the new child has
2596 * a "powered" LED, users should notice we didn't enable it
2597 * (without reading syslog), even without per-port LEDs
2598 * on the parent.
2599 */
2600 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
55c52718 2601 && udev->bus_mA <= 100) {
1da177e4
LT		 2602 u16 devstat;
2603
2604 status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2605 &devstat);
55c52718 2606 if (status < 2) {
1da177e4
LT		 2607 dev_dbg(&udev->dev, "get status %d ?\n", status);
2608 goto loop_disable;
2609 }
55c52718 2610 le16_to_cpus(&devstat);
1da177e4
LT		 2611 if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2612 dev_err(&udev->dev,
2613 "can't connect bus-powered hub "
2614 "to this port\n");
2615 if (hub->has_indicators) {
2616 hub->indicator[port1-1] =
2617 INDICATOR_AMBER_BLINK;
2618 schedule_work (&hub->leds);
2619 }
2620 status = -ENOTCONN; /* Don't retry */
2621 goto loop_disable;
2622 }
2623 }
2624
2625 /* check for devices running slower than they could */
2626 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2627 && udev->speed == USB_SPEED_FULL
2628 && highspeed_hubs != 0)
2629 check_highspeed (hub, udev, port1);
2630
2631 /* Store the parent's children[] pointer. At this point
2632 * udev becomes globally accessible, although presumably
2633 * no one will look at it until hdev is unlocked.
2634 */
1da177e4
LT		 2635 status = 0;
2636
2637 /* We mustn't add new devices if the parent hub has
2638 * been disconnected; we would race with the
2639 * recursively_mark_NOTATTACHED() routine.
2640 */
2641 spin_lock_irq(&device_state_lock);
2642 if (hdev->state == USB_STATE_NOTATTACHED)
2643 status = -ENOTCONN;
2644 else
2645 hdev->children[port1-1] = udev;
2646 spin_unlock_irq(&device_state_lock);
2647
2648 /* Run it through the hoops (find a driver, etc) */
2649 if (!status) {
2650 status = usb_new_device(udev);
2651 if (status) {
2652 spin_lock_irq(&device_state_lock);
2653 hdev->children[port1-1] = NULL;
2654 spin_unlock_irq(&device_state_lock);
2655 }
2656 }
2657
1da177e4
LT		 2658 if (status)
2659 goto loop_disable;
2660
2661 status = hub_power_remaining(hub);
2662 if (status)
55c52718 2663 dev_dbg(hub_dev, "%dmA power budget left\n", status);
1da177e4
LT		 2664
2665 return;
2666
2667loop_disable:
2668 hub_port_disable(hub, port1, 1);
2669loop:
2670 ep0_reinit(udev);
2671 release_address(udev);
2672 usb_put_dev(udev);
2673 if (status == -ENOTCONN)
2674 break;
2675 }
2676
2677done:
2678 hub_port_disable(hub, port1, 1);
2679}
2680
2681static void hub_events(void)
2682{
2683 struct list_head *tmp;
2684 struct usb_device *hdev;
2685 struct usb_interface *intf;
2686 struct usb_hub *hub;
2687 struct device *hub_dev;
2688 u16 hubstatus;
2689 u16 hubchange;
2690 u16 portstatus;
2691 u16 portchange;
2692 int i, ret;
2693 int connect_change;
2694
2695 /*
2696 * We restart the list every time to avoid a deadlock with
2697 * deleting hubs downstream from this one. This should be
2698 * safe since we delete the hub from the event list.
2699 * Not the most efficient, but avoids deadlocks.
2700 */
2701 while (1) {
2702
2703 /* Grab the first entry at the beginning of the list */
2704 spin_lock_irq(&hub_event_lock);
2705 if (list_empty(&hub_event_list)) {
2706 spin_unlock_irq(&hub_event_lock);
2707 break;
2708 }
2709
2710 tmp = hub_event_list.next;
2711 list_del_init(tmp);
2712
2713 hub = list_entry(tmp, struct usb_hub, event_list);
2714 hdev = hub->hdev;
2715 intf = to_usb_interface(hub->intfdev);
2716 hub_dev = &intf->dev;
2717
979d5199
DB		 2718 i = hub->resume_root_hub;
2719
2720 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x%s\n",
1da177e4
LT		 2721 hdev->state, hub->descriptor
2722 ? hub->descriptor->bNbrPorts
2723 : 0,
2724 /* NOTE: expects max 15 ports... */
2725 (u16) hub->change_bits[0],
979d5199
DB		 2726 (u16) hub->event_bits[0],
2727 i ? ", resume root" : "");
1da177e4
LT		 2728
2729 usb_get_intf(intf);
1da177e4
LT		 2730 spin_unlock_irq(&hub_event_lock);
2731
979d5199
DB		 2732 /* Is this is a root hub wanting to reactivate the downstream
2733 * ports? If so, be sure the interface resumes even if its
2734 * stub "device" node was never suspended.
2735 */
2736 if (i) {
979d5199
DB		 2737 dpm_runtime_resume(&hdev->dev);
2738 dpm_runtime_resume(&intf->dev);
2425e9fe
AS		 2739 usb_put_intf(intf);
2740 continue;
979d5199 2741 }
1da177e4
LT		 2742
2743 /* Lock the device, then check to see if we were
2744 * disconnected while waiting for the lock to succeed. */
2745 if (locktree(hdev) < 0) {
2746 usb_put_intf(intf);
2747 continue;
2748 }
2749 if (hub != usb_get_intfdata(intf))
2750 goto loop;
2751
2752 /* If the hub has died, clean up after it */
2753 if (hdev->state == USB_STATE_NOTATTACHED) {
7de18d8b
AS		 2754 hub->error = -ENODEV;
2755 hub_pre_reset(intf);
1da177e4
LT		 2756 goto loop;
2757 }
2758
2759 /* If this is an inactive or suspended hub, do nothing */
2760 if (hub->quiescing)
2761 goto loop;
2762
2763 if (hub->error) {
2764 dev_dbg (hub_dev, "resetting for error %d\n",
2765 hub->error);
2766
7de18d8b 2767 ret = usb_reset_composite_device(hdev, intf);
1da177e4
LT		 2768 if (ret) {
2769 dev_dbg (hub_dev,
2770 "error resetting hub: %d\n", ret);
2771 goto loop;
2772 }
2773
2774 hub->nerrors = 0;
2775 hub->error = 0;
2776 }
2777
2778 /* deal with port status changes */
2779 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2780 if (test_bit(i, hub->busy_bits))
2781 continue;
2782 connect_change = test_bit(i, hub->change_bits);
2783 if (!test_and_clear_bit(i, hub->event_bits) &&
2784 !connect_change && !hub->activating)
2785 continue;
2786
2787 ret = hub_port_status(hub, i,
2788 &portstatus, &portchange);
2789 if (ret < 0)
2790 continue;
2791
2792 if (hub->activating && !hdev->children[i-1] &&
2793 (portstatus &
2794 USB_PORT_STAT_CONNECTION))
2795 connect_change = 1;
2796
2797 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2798 clear_port_feature(hdev, i,
2799 USB_PORT_FEAT_C_CONNECTION);
2800 connect_change = 1;
2801 }
2802
2803 if (portchange & USB_PORT_STAT_C_ENABLE) {
2804 if (!connect_change)
2805 dev_dbg (hub_dev,
2806 "port %d enable change, "
2807 "status %08x\n",
2808 i, portstatus);
2809 clear_port_feature(hdev, i,
2810 USB_PORT_FEAT_C_ENABLE);
2811
2812 /*
2813 * EM interference sometimes causes badly
2814 * shielded USB devices to be shutdown by
2815 * the hub, this hack enables them again.
2816 * Works at least with mouse driver.
2817 */
2818 if (!(portstatus & USB_PORT_STAT_ENABLE)
2819 && !connect_change
2820 && hdev->children[i-1]) {
2821 dev_err (hub_dev,
2822 "port %i "
2823 "disabled by hub (EMI?), "
2824 "re-enabling...\n",
2825 i);
2826 connect_change = 1;
2827 }
2828 }
2829
2830 if (portchange & USB_PORT_STAT_C_SUSPEND) {
2831 clear_port_feature(hdev, i,
2832 USB_PORT_FEAT_C_SUSPEND);
2833 if (hdev->children[i-1]) {
2834 ret = remote_wakeup(hdev->
2835 children[i-1]);
2836 if (ret < 0)
2837 connect_change = 1;
2838 } else {
2839 ret = -ENODEV;
2840 hub_port_disable(hub, i, 1);
2841 }
2842 dev_dbg (hub_dev,
2843 "resume on port %d, status %d\n",
2844 i, ret);
2845 }
2846
2847 if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2848 dev_err (hub_dev,
2849 "over-current change on port %d\n",
2850 i);
2851 clear_port_feature(hdev, i,
2852 USB_PORT_FEAT_C_OVER_CURRENT);
2853 hub_power_on(hub);
2854 }
2855
2856 if (portchange & USB_PORT_STAT_C_RESET) {
2857 dev_dbg (hub_dev,
2858 "reset change on port %d\n",
2859 i);
2860 clear_port_feature(hdev, i,
2861 USB_PORT_FEAT_C_RESET);
2862 }
2863
2864 if (connect_change)
2865 hub_port_connect_change(hub, i,
2866 portstatus, portchange);
2867 } /* end for i */
2868
2869 /* deal with hub status changes */
2870 if (test_and_clear_bit(0, hub->event_bits) == 0)
2871 ; /* do nothing */
2872 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2873 dev_err (hub_dev, "get_hub_status failed\n");
2874 else {
2875 if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2876 dev_dbg (hub_dev, "power change\n");
2877 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
55c52718
AS		 2878 if (hubstatus & HUB_STATUS_LOCAL_POWER)
2879 /* FIXME: Is this always true? */
2880 hub->limited_power = 0;
2881 else
2882 hub->limited_power = 1;
1da177e4
LT		 2883 }
2884 if (hubchange & HUB_CHANGE_OVERCURRENT) {
2885 dev_dbg (hub_dev, "overcurrent change\n");
2886 msleep(500); /* Cool down */
2887 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2888 hub_power_on(hub);
2889 }
2890 }
2891
2892 hub->activating = 0;
2893
d5926ae7
AS		 2894 /* If this is a root hub, tell the HCD it's okay to
2895 * re-enable port-change interrupts now. */
2896 if (!hdev->parent)
2897 usb_enable_root_hub_irq(hdev->bus);
2898
1da177e4
LT		 2899loop:
2900 usb_unlock_device(hdev);
2901 usb_put_intf(intf);
2902
2903 } /* end while (1) */
2904}
2905
2906static int hub_thread(void *__unused)
2907{
1da177e4
LT		 2908 do {
2909 hub_events();
9c8d6178 2910 wait_event_interruptible(khubd_wait,
2911 !list_empty(&hub_event_list) ||
2912 kthread_should_stop());
3e1d1d28 2913 try_to_freeze();
9c8d6178 2914 } while (!kthread_should_stop() || !list_empty(&hub_event_list));
1da177e4 2915
9c8d6178 2916 pr_debug("%s: khubd exiting\n", usbcore_name);
2917 return 0;
1da177e4
LT		 2918}
2919
2920static struct usb_device_id hub_id_table [] = {
2921 { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2922 .bDeviceClass = USB_CLASS_HUB},
2923 { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2924 .bInterfaceClass = USB_CLASS_HUB},
2925 { } /* Terminating entry */
2926};
2927
2928MODULE_DEVICE_TABLE (usb, hub_id_table);
2929
2930static struct usb_driver hub_driver = {
1da177e4
LT		 2931 .name = "hub",
2932 .probe = hub_probe,
2933 .disconnect = hub_disconnect,
2934 .suspend = hub_suspend,
2935 .resume = hub_resume,
7de18d8b
AS		 2936 .pre_reset = hub_pre_reset,
2937 .post_reset = hub_post_reset,
1da177e4
LT		 2938 .ioctl = hub_ioctl,
2939 .id_table = hub_id_table,
2940};
2941
2942int usb_hub_init(void)
2943{
1da177e4
LT		 2944 if (usb_register(&hub_driver) < 0) {
2945 printk(KERN_ERR "%s: can't register hub driver\n",
2946 usbcore_name);
2947 return -1;
2948 }
2949
9c8d6178 2950 khubd_task = kthread_run(hub_thread, NULL, "khubd");
2951 if (!IS_ERR(khubd_task))
1da177e4 2952 return 0;
1da177e4
LT		 2953
2954 /* Fall through if kernel_thread failed */
2955 usb_deregister(&hub_driver);
2956 printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2957
2958 return -1;
2959}
2960
2961void usb_hub_cleanup(void)
2962{
9c8d6178 2963 kthread_stop(khubd_task);
1da177e4
LT		 2964
2965 /*
2966 * Hub resources are freed for us by usb_deregister. It calls
2967 * usb_driver_purge on every device which in turn calls that
2968 * devices disconnect function if it is using this driver.
2969 * The hub_disconnect function takes care of releasing the
2970 * individual hub resources. -greg
2971 */
2972 usb_deregister(&hub_driver);
2973} /* usb_hub_cleanup() */
2974
1da177e4
LT		 2975static int config_descriptors_changed(struct usb_device *udev)
2976{
2977 unsigned index;
2978 unsigned len = 0;
2979 struct usb_config_descriptor *buf;
2980
2981 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2982 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2983 len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2984 }
2985 buf = kmalloc (len, SLAB_KERNEL);
2986 if (buf == NULL) {
2987 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2988 /* assume the worst */
2989 return 1;
2990 }
2991 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2992 int length;
2993 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2994
2995 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2996 old_length);
2997 if (length < old_length) {
2998 dev_dbg(&udev->dev, "config index %d, error %d\n",
2999 index, length);
3000 break;
3001 }
3002 if (memcmp (buf, udev->rawdescriptors[index], old_length)
3003 != 0) {
3004 dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
3005 index, buf->bConfigurationValue);
3006 break;
3007 }
3008 }
3009 kfree(buf);
3010 return index != udev->descriptor.bNumConfigurations;
3011}
3012
3013/**
3014 * usb_reset_device - perform a USB port reset to reinitialize a device
3015 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
3016 *
79efa097
AS		 3017 * WARNING - don't use this routine to reset a composite device
3018 * (one with multiple interfaces owned by separate drivers)!
3019 * Use usb_reset_composite_device() instead.
1da177e4
LT		 3020 *
3021 * Do a port reset, reassign the device's address, and establish its
3022 * former operating configuration. If the reset fails, or the device's
3023 * descriptors change from their values before the reset, or the original
3024 * configuration and altsettings cannot be restored, a flag will be set
3025 * telling khubd to pretend the device has been disconnected and then
3026 * re-connected. All drivers will be unbound, and the device will be
3027 * re-enumerated and probed all over again.
3028 *
3029 * Returns 0 if the reset succeeded, -ENODEV if the device has been
3030 * flagged for logical disconnection, or some other negative error code
3031 * if the reset wasn't even attempted.
3032 *
3033 * The caller must own the device lock. For example, it's safe to use
3034 * this from a driver probe() routine after downloading new firmware.
3035 * For calls that might not occur during probe(), drivers should lock
3036 * the device using usb_lock_device_for_reset().
3037 */
3038int usb_reset_device(struct usb_device *udev)
3039{
3040 struct usb_device *parent_hdev = udev->parent;
3041 struct usb_hub *parent_hub;
3042 struct usb_device_descriptor descriptor = udev->descriptor;
12c3da34
AS		 3043 int i, ret = 0;
3044 int port1 = udev->portnum;
1da177e4
LT		 3045
3046 if (udev->state == USB_STATE_NOTATTACHED ||
3047 udev->state == USB_STATE_SUSPENDED) {
3048 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3049 udev->state);
3050 return -EINVAL;
3051 }
3052
3053 if (!parent_hdev) {
3054 /* this requires hcd-specific logic; see OHCI hc_restart() */
3055 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
3056 return -EISDIR;
3057 }
1da177e4
LT		 3058 parent_hub = hdev_to_hub(parent_hdev);
3059
1da177e4
LT		 3060 set_bit(port1, parent_hub->busy_bits);
3061 for (i = 0; i < SET_CONFIG_TRIES; ++i) {
3062
3063 /* ep0 maxpacket size may change; let the HCD know about it.
3064 * Other endpoints will be handled by re-enumeration. */
3065 ep0_reinit(udev);
3066 ret = hub_port_init(parent_hub, udev, port1, i);
3067 if (ret >= 0)
3068 break;
3069 }
3070 clear_bit(port1, parent_hub->busy_bits);
3071 if (ret < 0)
3072 goto re_enumerate;
3073
3074 /* Device might have changed firmware (DFU or similar) */
3075 if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
3076 || config_descriptors_changed (udev)) {
3077 dev_info(&udev->dev, "device firmware changed\n");
3078 udev->descriptor = descriptor; /* for disconnect() calls */
3079 goto re_enumerate;
3080 }
3081
3082 if (!udev->actconfig)
3083 goto done;
3084
3085 ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3086 USB_REQ_SET_CONFIGURATION, 0,
3087 udev->actconfig->desc.bConfigurationValue, 0,
3088 NULL, 0, USB_CTRL_SET_TIMEOUT);
3089 if (ret < 0) {
3090 dev_err(&udev->dev,
3091 "can't restore configuration #%d (error=%d)\n",
3092 udev->actconfig->desc.bConfigurationValue, ret);
3093 goto re_enumerate;
3094 }
3095 usb_set_device_state(udev, USB_STATE_CONFIGURED);
3096
3097 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3098 struct usb_interface *intf = udev->actconfig->interface[i];
3099 struct usb_interface_descriptor *desc;
3100
3101 /* set_interface resets host side toggle even
3102 * for altsetting zero. the interface may have no driver.
3103 */
3104 desc = &intf->cur_altsetting->desc;
3105 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3106 desc->bAlternateSetting);
3107 if (ret < 0) {
3108 dev_err(&udev->dev, "failed to restore interface %d "
3109 "altsetting %d (error=%d)\n",
3110 desc->bInterfaceNumber,
3111 desc->bAlternateSetting,
3112 ret);
3113 goto re_enumerate;
3114 }
3115 }
3116
3117done:
1da177e4
LT		 3118 return 0;
3119
3120re_enumerate:
3121 hub_port_logical_disconnect(parent_hub, port1);
3122 return -ENODEV;
3123}
79efa097
AS		 3124
3125/**
3126 * usb_reset_composite_device - warn interface drivers and perform a USB port reset
3127 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
3128 * @iface: interface bound to the driver making the request (optional)
3129 *
3130 * Warns all drivers bound to registered interfaces (using their pre_reset
3131 * method), performs the port reset, and then lets the drivers know that
3132 * the reset is over (using their post_reset method).
3133 *
3134 * Return value is the same as for usb_reset_device().
3135 *
3136 * The caller must own the device lock. For example, it's safe to use
3137 * this from a driver probe() routine after downloading new firmware.
3138 * For calls that might not occur during probe(), drivers should lock
3139 * the device using usb_lock_device_for_reset().
3140 *
3141 * The interface locks are acquired during the pre_reset stage and released
3142 * during the post_reset stage. However if iface is not NULL and is
3143 * currently being probed, we assume that the caller already owns its
3144 * lock.
3145 */
3146int usb_reset_composite_device(struct usb_device *udev,
3147 struct usb_interface *iface)
3148{
3149 int ret;
3150 struct usb_host_config *config = udev->actconfig;
3151
3152 if (udev->state == USB_STATE_NOTATTACHED ||
3153 udev->state == USB_STATE_SUSPENDED) {
3154 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3155 udev->state);
3156 return -EINVAL;
3157 }
3158
3159 if (iface && iface->condition != USB_INTERFACE_BINDING)
3160 iface = NULL;
3161
3162 if (config) {
3163 int i;
3164 struct usb_interface *cintf;
3165 struct usb_driver *drv;
3166
3167 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
3168 cintf = config->interface[i];
3169 if (cintf != iface)
3170 down(&cintf->dev.sem);
3171 if (device_is_registered(&cintf->dev) &&
3172 cintf->dev.driver) {
3173 drv = to_usb_driver(cintf->dev.driver);
3174 if (drv->pre_reset)
3175 (drv->pre_reset)(cintf);
3176 }
3177 }
3178 }
3179
3180 ret = usb_reset_device(udev);
3181
3182 if (config) {
3183 int i;
3184 struct usb_interface *cintf;
3185 struct usb_driver *drv;
3186
3187 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
3188 cintf = config->interface[i];
3189 if (device_is_registered(&cintf->dev) &&
3190 cintf->dev.driver) {
3191 drv = to_usb_driver(cintf->dev.driver);
3192 if (drv->post_reset)
3193 (drv->post_reset)(cintf);
3194 }
3195 if (cintf != iface)
3196 up(&cintf->dev.sem);
3197 }
3198 }
3199
3200 return ret;
3201}
Linux 6.x block layer and io_uring tree(s)