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[PATCH] remove duplicated resume path code
[linux-2.6/x86.git] / drivers / usb / core / hub.c
blobb2ae9b6ca4dbed343dedd52fa1461933c61872c3
1 /*
2 * USB hub driver.
3 *
4 * (C) Copyright 1999 Linus Torvalds
5 * (C) Copyright 1999 Johannes Erdfelt
6 * (C) Copyright 1999 Gregory P. Smith
7 * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
8 *
9 */
10
11 #include <linux/config.h>
12 #ifdef CONFIG_USB_DEBUG
13 #define DEBUG
14 #else
15 #undef DEBUG
16 #endif
17 #include <linux/kernel.h>
18 #include <linux/errno.h>
19 #include <linux/module.h>
20 #include <linux/moduleparam.h>
21 #include <linux/completion.h>
22 #include <linux/sched.h>
23 #include <linux/list.h>
24 #include <linux/slab.h>
25 #include <linux/smp_lock.h>
26 #include <linux/ioctl.h>
27 #include <linux/usb.h>
28 #include <linux/usbdevice_fs.h>
29 #include <linux/kthread.h>
30
31 #include <asm/semaphore.h>
32 #include <asm/uaccess.h>
33 #include <asm/byteorder.h>
34
35 #include "usb.h"
36 #include "hcd.h"
37 #include "hub.h"
38
39 /* Protect struct usb_device->state and ->children members
40 * Note: Both are also protected by ->serialize, except that ->state can
41 * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
42 static DEFINE_SPINLOCK(device_state_lock);
43
44 /* khubd's worklist and its lock */
45 static DEFINE_SPINLOCK(hub_event_lock);
46 static LIST_HEAD(hub_event_list); /* List of hubs needing servicing */
47
48 /* Wakes up khubd */
49 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
50
51 static struct task_struct *khubd_task;
52
53 /* cycle leds on hubs that aren't blinking for attention */
54 static int blinkenlights = 0;
55 module_param (blinkenlights, bool, S_IRUGO);
56 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
57
58 /*
59 * As of 2.6.10 we introduce a new USB device initialization scheme which
60 * closely resembles the way Windows works. Hopefully it will be compatible
61 * with a wider range of devices than the old scheme. However some previously
62 * working devices may start giving rise to "device not accepting address"
63 * errors; if that happens the user can try the old scheme by adjusting the
64 * following module parameters.
65 *
66 * For maximum flexibility there are two boolean parameters to control the
67 * hub driver's behavior. On the first initialization attempt, if the
68 * "old_scheme_first" parameter is set then the old scheme will be used,
69 * otherwise the new scheme is used. If that fails and "use_both_schemes"
70 * is set, then the driver will make another attempt, using the other scheme.
71 */
72 static int old_scheme_first = 0;
73 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
74 MODULE_PARM_DESC(old_scheme_first,
75 "start with the old device initialization scheme");
76
77 static int use_both_schemes = 1;
78 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
79 MODULE_PARM_DESC(use_both_schemes,
80 "try the other device initialization scheme if the "
81 "first one fails");
82
83
84 #ifdef DEBUG
85 static inline char *portspeed (int portstatus)
86 {
87 if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
88 return "480 Mb/s";
89 else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
90 return "1.5 Mb/s";
91 else
92 return "12 Mb/s";
93 }
94 #endif
95
96 /* Note that hdev or one of its children must be locked! */
97 static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
98 {
99 return usb_get_intfdata(hdev->actconfig->interface[0]);
100 }
101
102 /* USB 2.0 spec Section 11.24.4.5 */
103 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
104 {
105 int i, ret;
106
107 for (i = 0; i < 3; i++) {
108 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
109 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
110 USB_DT_HUB << 8, 0, data, size,
111 USB_CTRL_GET_TIMEOUT);
112 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
113 return ret;
114 }
115 return -EINVAL;
116 }
117
118 /*
119 * USB 2.0 spec Section 11.24.2.1
120 */
121 static int clear_hub_feature(struct usb_device *hdev, int feature)
122 {
123 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
124 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
125 }
126
127 /*
128 * USB 2.0 spec Section 11.24.2.2
129 */
130 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
131 {
132 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
133 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
134 NULL, 0, 1000);
135 }
136
137 /*
138 * USB 2.0 spec Section 11.24.2.13
139 */
140 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
141 {
142 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
143 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
144 NULL, 0, 1000);
145 }
146
147 /*
148 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
149 * for info about using port indicators
150 */
151 static void set_port_led(
152 struct usb_hub *hub,
153 int port1,
154 int selector
155 )
156 {
157 int status = set_port_feature(hub->hdev, (selector << 8) | port1,
158 USB_PORT_FEAT_INDICATOR);
159 if (status < 0)
160 dev_dbg (hub->intfdev,
161 "port %d indicator %s status %d\n",
162 port1,
163 ({ char *s; switch (selector) {
164 case HUB_LED_AMBER: s = "amber"; break;
165 case HUB_LED_GREEN: s = "green"; break;
166 case HUB_LED_OFF: s = "off"; break;
167 case HUB_LED_AUTO: s = "auto"; break;
168 default: s = "??"; break;
169 }; s; }),
170 status);
171 }
172
173 #define LED_CYCLE_PERIOD ((2*HZ)/3)
174
175 static void led_work (void *__hub)
176 {
177 struct usb_hub *hub = __hub;
178 struct usb_device *hdev = hub->hdev;
179 unsigned i;
180 unsigned changed = 0;
181 int cursor = -1;
182
183 if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
184 return;
185
186 for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
187 unsigned selector, mode;
188
189 /* 30%-50% duty cycle */
190
191 switch (hub->indicator[i]) {
192 /* cycle marker */
193 case INDICATOR_CYCLE:
194 cursor = i;
195 selector = HUB_LED_AUTO;
196 mode = INDICATOR_AUTO;
197 break;
198 /* blinking green = sw attention */
199 case INDICATOR_GREEN_BLINK:
200 selector = HUB_LED_GREEN;
201 mode = INDICATOR_GREEN_BLINK_OFF;
202 break;
203 case INDICATOR_GREEN_BLINK_OFF:
204 selector = HUB_LED_OFF;
205 mode = INDICATOR_GREEN_BLINK;
206 break;
207 /* blinking amber = hw attention */
208 case INDICATOR_AMBER_BLINK:
209 selector = HUB_LED_AMBER;
210 mode = INDICATOR_AMBER_BLINK_OFF;
211 break;
212 case INDICATOR_AMBER_BLINK_OFF:
213 selector = HUB_LED_OFF;
214 mode = INDICATOR_AMBER_BLINK;
215 break;
216 /* blink green/amber = reserved */
217 case INDICATOR_ALT_BLINK:
218 selector = HUB_LED_GREEN;
219 mode = INDICATOR_ALT_BLINK_OFF;
220 break;
221 case INDICATOR_ALT_BLINK_OFF:
222 selector = HUB_LED_AMBER;
223 mode = INDICATOR_ALT_BLINK;
224 break;
225 default:
226 continue;
227 }
228 if (selector != HUB_LED_AUTO)
229 changed = 1;
230 set_port_led(hub, i + 1, selector);
231 hub->indicator[i] = mode;
232 }
233 if (!changed && blinkenlights) {
234 cursor++;
235 cursor %= hub->descriptor->bNbrPorts;
236 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
237 hub->indicator[cursor] = INDICATOR_CYCLE;
238 changed++;
239 }
240 if (changed)
241 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
242 }
243
244 /* use a short timeout for hub/port status fetches */
245 #define USB_STS_TIMEOUT 1000
246 #define USB_STS_RETRIES 5
247
248 /*
249 * USB 2.0 spec Section 11.24.2.6
250 */
251 static int get_hub_status(struct usb_device *hdev,
252 struct usb_hub_status *data)
253 {
254 int i, status = -ETIMEDOUT;
255
256 for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
257 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
258 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
259 data, sizeof(*data), USB_STS_TIMEOUT);
260 }
261 return status;
262 }
263
264 /*
265 * USB 2.0 spec Section 11.24.2.7
266 */
267 static int get_port_status(struct usb_device *hdev, int port1,
268 struct usb_port_status *data)
269 {
270 int i, status = -ETIMEDOUT;
271
272 for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
273 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
274 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
275 data, sizeof(*data), USB_STS_TIMEOUT);
276 }
277 return status;
278 }
279
280 static void kick_khubd(struct usb_hub *hub)
281 {
282 unsigned long flags;
283
284 spin_lock_irqsave(&hub_event_lock, flags);
285 if (list_empty(&hub->event_list)) {
286 list_add_tail(&hub->event_list, &hub_event_list);
287 wake_up(&khubd_wait);
288 }
289 spin_unlock_irqrestore(&hub_event_lock, flags);
290 }
291
292 void usb_kick_khubd(struct usb_device *hdev)
293 {
294 kick_khubd(hdev_to_hub(hdev));
295 }
296
297
298 /* completion function, fires on port status changes and various faults */
299 static void hub_irq(struct urb *urb, struct pt_regs *regs)
300 {
301 struct usb_hub *hub = (struct usb_hub *)urb->context;
302 int status;
303 int i;
304 unsigned long bits;
305
306 switch (urb->status) {
307 case -ENOENT: /* synchronous unlink */
308 case -ECONNRESET: /* async unlink */
309 case -ESHUTDOWN: /* hardware going away */
310 return;
311
312 default: /* presumably an error */
313 /* Cause a hub reset after 10 consecutive errors */
314 dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
315 if ((++hub->nerrors < 10) || hub->error)
316 goto resubmit;
317 hub->error = urb->status;
318 /* FALL THROUGH */
319
320 /* let khubd handle things */
321 case 0: /* we got data: port status changed */
322 bits = 0;
323 for (i = 0; i < urb->actual_length; ++i)
324 bits |= ((unsigned long) ((*hub->buffer)[i]))
325 << (i*8);
326 hub->event_bits[0] = bits;
327 break;
328 }
329
330 hub->nerrors = 0;
331
332 /* Something happened, let khubd figure it out */
333 kick_khubd(hub);
334
335 resubmit:
336 if (hub->quiescing)
337 return;
338
339 if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
340 && status != -ENODEV && status != -EPERM)
341 dev_err (hub->intfdev, "resubmit --> %d\n", status);
342 }
343
344 /* USB 2.0 spec Section 11.24.2.3 */
345 static inline int
346 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
347 {
348 return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
349 HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
350 tt, NULL, 0, 1000);
351 }
352
353 /*
354 * enumeration blocks khubd for a long time. we use keventd instead, since
355 * long blocking there is the exception, not the rule. accordingly, HCDs
356 * talking to TTs must queue control transfers (not just bulk and iso), so
357 * both can talk to the same hub concurrently.
358 */
359 static void hub_tt_kevent (void *arg)
360 {
361 struct usb_hub *hub = arg;
362 unsigned long flags;
363
364 spin_lock_irqsave (&hub->tt.lock, flags);
365 while (!list_empty (&hub->tt.clear_list)) {
366 struct list_head *temp;
367 struct usb_tt_clear *clear;
368 struct usb_device *hdev = hub->hdev;
369 int status;
370
371 temp = hub->tt.clear_list.next;
372 clear = list_entry (temp, struct usb_tt_clear, clear_list);
373 list_del (&clear->clear_list);
374
375 /* drop lock so HCD can concurrently report other TT errors */
376 spin_unlock_irqrestore (&hub->tt.lock, flags);
377 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
378 spin_lock_irqsave (&hub->tt.lock, flags);
379
380 if (status)
381 dev_err (&hdev->dev,
382 "clear tt %d (%04x) error %d\n",
383 clear->tt, clear->devinfo, status);
384 kfree(clear);
385 }
386 spin_unlock_irqrestore (&hub->tt.lock, flags);
387 }
388
389 /**
390 * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
391 * @udev: the device whose split transaction failed
392 * @pipe: identifies the endpoint of the failed transaction
393 *
394 * High speed HCDs use this to tell the hub driver that some split control or
395 * bulk transaction failed in a way that requires clearing internal state of
396 * a transaction translator. This is normally detected (and reported) from
397 * interrupt context.
398 *
399 * It may not be possible for that hub to handle additional full (or low)
400 * speed transactions until that state is fully cleared out.
401 */
402 void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
403 {
404 struct usb_tt *tt = udev->tt;
405 unsigned long flags;
406 struct usb_tt_clear *clear;
407
408 /* we've got to cope with an arbitrary number of pending TT clears,
409 * since each TT has "at least two" buffers that can need it (and
410 * there can be many TTs per hub). even if they're uncommon.
411 */
412 if ((clear = kmalloc (sizeof *clear, SLAB_ATOMIC)) == NULL) {
413 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
414 /* FIXME recover somehow ... RESET_TT? */
415 return;
416 }
417
418 /* info that CLEAR_TT_BUFFER needs */
419 clear->tt = tt->multi ? udev->ttport : 1;
420 clear->devinfo = usb_pipeendpoint (pipe);
421 clear->devinfo |= udev->devnum << 4;
422 clear->devinfo |= usb_pipecontrol (pipe)
423 ? (USB_ENDPOINT_XFER_CONTROL << 11)
424 : (USB_ENDPOINT_XFER_BULK << 11);
425 if (usb_pipein (pipe))
426 clear->devinfo |= 1 << 15;
427
428 /* tell keventd to clear state for this TT */
429 spin_lock_irqsave (&tt->lock, flags);
430 list_add_tail (&clear->clear_list, &tt->clear_list);
431 schedule_work (&tt->kevent);
432 spin_unlock_irqrestore (&tt->lock, flags);
433 }
434
435 static void hub_power_on(struct usb_hub *hub)
436 {
437 int port1;
438 unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
439
440 /* if hub supports power switching, enable power on each port */
441 if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_LPSM) < 2) {
442 dev_dbg(hub->intfdev, "enabling power on all ports\n");
443 for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
444 set_port_feature(hub->hdev, port1,
445 USB_PORT_FEAT_POWER);
446 }
447
448 /* Wait at least 100 msec for power to become stable */
449 msleep(max(pgood_delay, (unsigned) 100));
450 }
451
452 static void hub_quiesce(struct usb_hub *hub)
453 {
454 /* stop khubd and related activity */
455 hub->quiescing = 1;
456 hub->activating = 0;
457 usb_kill_urb(hub->urb);
458 if (hub->has_indicators)
459 cancel_delayed_work(&hub->leds);
460 if (hub->has_indicators || hub->tt.hub)
461 flush_scheduled_work();
462 }
463
464 static void hub_activate(struct usb_hub *hub)
465 {
466 int status;
467
468 hub->quiescing = 0;
469 hub->activating = 1;
470 status = usb_submit_urb(hub->urb, GFP_NOIO);
471 if (status < 0)
472 dev_err(hub->intfdev, "activate --> %d\n", status);
473 if (hub->has_indicators && blinkenlights)
474 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
475
476 /* scan all ports ASAP */
477 kick_khubd(hub);
478 }
479
480 static int hub_hub_status(struct usb_hub *hub,
481 u16 *status, u16 *change)
482 {
483 int ret;
484
485 ret = get_hub_status(hub->hdev, &hub->status->hub);
486 if (ret < 0)
487 dev_err (hub->intfdev,
488 "%s failed (err = %d)\n", __FUNCTION__, ret);
489 else {
490 *status = le16_to_cpu(hub->status->hub.wHubStatus);
491 *change = le16_to_cpu(hub->status->hub.wHubChange);
492 ret = 0;
493 }
494 return ret;
495 }
496
497 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
498 {
499 struct usb_device *hdev = hub->hdev;
500 int ret;
501
502 if (hdev->children[port1-1] && set_state) {
503 usb_set_device_state(hdev->children[port1-1],
504 USB_STATE_NOTATTACHED);
505 }
506 ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
507 if (ret)
508 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
509 port1, ret);
510
511 return ret;
512 }
513
514 static int hub_configure(struct usb_hub *hub,
515 struct usb_endpoint_descriptor *endpoint)
516 {
517 struct usb_device *hdev = hub->hdev;
518 struct device *hub_dev = hub->intfdev;
519 u16 hubstatus, hubchange;
520 unsigned int pipe;
521 int maxp, ret;
522 char *message;
523
524 hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
525 &hub->buffer_dma);
526 if (!hub->buffer) {
527 message = "can't allocate hub irq buffer";
528 ret = -ENOMEM;
529 goto fail;
530 }
531
532 hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
533 if (!hub->status) {
534 message = "can't kmalloc hub status buffer";
535 ret = -ENOMEM;
536 goto fail;
537 }
538
539 hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
540 if (!hub->descriptor) {
541 message = "can't kmalloc hub descriptor";
542 ret = -ENOMEM;
543 goto fail;
544 }
545
546 /* Request the entire hub descriptor.
547 * hub->descriptor can handle USB_MAXCHILDREN ports,
548 * but the hub can/will return fewer bytes here.
549 */
550 ret = get_hub_descriptor(hdev, hub->descriptor,
551 sizeof(*hub->descriptor));
552 if (ret < 0) {
553 message = "can't read hub descriptor";
554 goto fail;
555 } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
556 message = "hub has too many ports!";
557 ret = -ENODEV;
558 goto fail;
559 }
560
561 hdev->maxchild = hub->descriptor->bNbrPorts;
562 dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
563 (hdev->maxchild == 1) ? "" : "s");
564
565 le16_to_cpus(&hub->descriptor->wHubCharacteristics);
566
567 if (hub->descriptor->wHubCharacteristics & HUB_CHAR_COMPOUND) {
568 int i;
569 char portstr [USB_MAXCHILDREN + 1];
570
571 for (i = 0; i < hdev->maxchild; i++)
572 portstr[i] = hub->descriptor->DeviceRemovable
573 [((i + 1) / 8)] & (1 << ((i + 1) % 8))
574 ? 'F' : 'R';
575 portstr[hdev->maxchild] = 0;
576 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
577 } else
578 dev_dbg(hub_dev, "standalone hub\n");
579
580 switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_LPSM) {
581 case 0x00:
582 dev_dbg(hub_dev, "ganged power switching\n");
583 break;
584 case 0x01:
585 dev_dbg(hub_dev, "individual port power switching\n");
586 break;
587 case 0x02:
588 case 0x03:
589 dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
590 break;
591 }
592
593 switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) {
594 case 0x00:
595 dev_dbg(hub_dev, "global over-current protection\n");
596 break;
597 case 0x08:
598 dev_dbg(hub_dev, "individual port over-current protection\n");
599 break;
600 case 0x10:
601 case 0x18:
602 dev_dbg(hub_dev, "no over-current protection\n");
603 break;
604 }
605
606 spin_lock_init (&hub->tt.lock);
607 INIT_LIST_HEAD (&hub->tt.clear_list);
608 INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub);
609 switch (hdev->descriptor.bDeviceProtocol) {
610 case 0:
611 break;
612 case 1:
613 dev_dbg(hub_dev, "Single TT\n");
614 hub->tt.hub = hdev;
615 break;
616 case 2:
617 ret = usb_set_interface(hdev, 0, 1);
618 if (ret == 0) {
619 dev_dbg(hub_dev, "TT per port\n");
620 hub->tt.multi = 1;
621 } else
622 dev_err(hub_dev, "Using single TT (err %d)\n",
623 ret);
624 hub->tt.hub = hdev;
625 break;
626 default:
627 dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
628 hdev->descriptor.bDeviceProtocol);
629 break;
630 }
631
632 /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
633 switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_TTTT) {
634 case HUB_TTTT_8_BITS:
635 if (hdev->descriptor.bDeviceProtocol != 0) {
636 hub->tt.think_time = 666;
637 dev_dbg(hub_dev, "TT requires at most %d "
638 "FS bit times (%d ns)\n",
639 8, hub->tt.think_time);
640 }
641 break;
642 case HUB_TTTT_16_BITS:
643 hub->tt.think_time = 666 * 2;
644 dev_dbg(hub_dev, "TT requires at most %d "
645 "FS bit times (%d ns)\n",
646 16, hub->tt.think_time);
647 break;
648 case HUB_TTTT_24_BITS:
649 hub->tt.think_time = 666 * 3;
650 dev_dbg(hub_dev, "TT requires at most %d "
651 "FS bit times (%d ns)\n",
652 24, hub->tt.think_time);
653 break;
654 case HUB_TTTT_32_BITS:
655 hub->tt.think_time = 666 * 4;
656 dev_dbg(hub_dev, "TT requires at most %d "
657 "FS bit times (%d ns)\n",
658 32, hub->tt.think_time);
659 break;
660 }
661
662 /* probe() zeroes hub->indicator[] */
663 if (hub->descriptor->wHubCharacteristics & HUB_CHAR_PORTIND) {
664 hub->has_indicators = 1;
665 dev_dbg(hub_dev, "Port indicators are supported\n");
666 }
667
668 dev_dbg(hub_dev, "power on to power good time: %dms\n",
669 hub->descriptor->bPwrOn2PwrGood * 2);
670
671 /* power budgeting mostly matters with bus-powered hubs,
672 * and battery-powered root hubs (may provide just 8 mA).
673 */
674 ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
675 if (ret < 0) {
676 message = "can't get hub status";
677 goto fail;
678 }
679 le16_to_cpus(&hubstatus);
680 if (hdev == hdev->bus->root_hub) {
681 struct usb_hcd *hcd =
682 container_of(hdev->bus, struct usb_hcd, self);
683
684 hub->power_budget = min(500u, hcd->power_budget) / 2;
685 } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
686 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
687 hub->descriptor->bHubContrCurrent);
688 hub->power_budget = (501 - hub->descriptor->bHubContrCurrent)
689 / 2;
690 }
691 if (hub->power_budget)
692 dev_dbg(hub_dev, "%dmA bus power budget for children\n",
693 hub->power_budget * 2);
694
695
696 ret = hub_hub_status(hub, &hubstatus, &hubchange);
697 if (ret < 0) {
698 message = "can't get hub status";
699 goto fail;
700 }
701
702 /* local power status reports aren't always correct */
703 if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
704 dev_dbg(hub_dev, "local power source is %s\n",
705 (hubstatus & HUB_STATUS_LOCAL_POWER)
706 ? "lost (inactive)" : "good");
707
708 if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) == 0)
709 dev_dbg(hub_dev, "%sover-current condition exists\n",
710 (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
711
712 /* set up the interrupt endpoint */
713 pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
714 maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
715
716 if (maxp > sizeof(*hub->buffer))
717 maxp = sizeof(*hub->buffer);
718
719 hub->urb = usb_alloc_urb(0, GFP_KERNEL);
720 if (!hub->urb) {
721 message = "couldn't allocate interrupt urb";
722 ret = -ENOMEM;
723 goto fail;
724 }
725
726 usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
727 hub, endpoint->bInterval);
728 hub->urb->transfer_dma = hub->buffer_dma;
729 hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
730
731 /* maybe cycle the hub leds */
732 if (hub->has_indicators && blinkenlights)
733 hub->indicator [0] = INDICATOR_CYCLE;
734
735 hub_power_on(hub);
736 hub_activate(hub);
737 return 0;
738
739 fail:
740 dev_err (hub_dev, "config failed, %s (err %d)\n",
741 message, ret);
742 /* hub_disconnect() frees urb and descriptor */
743 return ret;
744 }
745
746 static unsigned highspeed_hubs;
747
748 /* Called after the hub driver is unbound from a hub with children */
749 static void hub_remove_children_work(void *__hub)
750 {
751 struct usb_hub *hub = __hub;
752 struct usb_device *hdev = hub->hdev;
753 int i;
754
755 kfree(hub);
756
757 usb_lock_device(hdev);
758 for (i = 0; i < hdev->maxchild; ++i) {
759 if (hdev->children[i])
760 usb_disconnect(&hdev->children[i]);
761 }
762 usb_unlock_device(hdev);
763 usb_put_dev(hdev);
764 }
765
766 static void hub_disconnect(struct usb_interface *intf)
767 {
768 struct usb_hub *hub = usb_get_intfdata (intf);
769 struct usb_device *hdev;
770 int n, port1;
771
772 usb_set_intfdata (intf, NULL);
773 hdev = hub->hdev;
774
775 if (hdev->speed == USB_SPEED_HIGH)
776 highspeed_hubs--;
777
778 hub_quiesce(hub);
779 usb_free_urb(hub->urb);
780 hub->urb = NULL;
781
782 spin_lock_irq(&hub_event_lock);
783 list_del_init(&hub->event_list);
784 spin_unlock_irq(&hub_event_lock);
785
786 kfree(hub->descriptor);
787 hub->descriptor = NULL;
788
789 kfree(hub->status);
790 hub->status = NULL;
791
792 if (hub->buffer) {
793 usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
794 hub->buffer_dma);
795 hub->buffer = NULL;
796 }
797
798 /* If there are any children then this is an unbind only, not a
799 * physical disconnection. The active ports must be disabled
800 * and later on we must call usb_disconnect(). We can't call
801 * it now because we may not hold the hub's device lock.
802 */
803 n = 0;
804 for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
805 if (hdev->children[port1 - 1]) {
806 ++n;
807 hub_port_disable(hub, port1, 1);
808 }
809 }
810
811 if (n == 0)
812 kfree(hub);
813 else {
814 /* Reuse the hub->leds work_struct for our own purposes */
815 INIT_WORK(&hub->leds, hub_remove_children_work, hub);
816 schedule_work(&hub->leds);
817 usb_get_dev(hdev);
818 }
819 }
820
821 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
822 {
823 struct usb_host_interface *desc;
824 struct usb_endpoint_descriptor *endpoint;
825 struct usb_device *hdev;
826 struct usb_hub *hub;
827
828 desc = intf->cur_altsetting;
829 hdev = interface_to_usbdev(intf);
830
831 /* Some hubs have a subclass of 1, which AFAICT according to the */
832 /* specs is not defined, but it works */
833 if ((desc->desc.bInterfaceSubClass != 0) &&
834 (desc->desc.bInterfaceSubClass != 1)) {
835 descriptor_error:
836 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
837 return -EIO;
838 }
839
840 /* Multiple endpoints? What kind of mutant ninja-hub is this? */
841 if (desc->desc.bNumEndpoints != 1)
842 goto descriptor_error;
843
844 endpoint = &desc->endpoint[0].desc;
845
846 /* Output endpoint? Curiouser and curiouser.. */
847 if (!(endpoint->bEndpointAddress & USB_DIR_IN))
848 goto descriptor_error;
849
850 /* If it's not an interrupt endpoint, we'd better punt! */
851 if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
852 != USB_ENDPOINT_XFER_INT)
853 goto descriptor_error;
854
855 /* We found a hub */
856 dev_info (&intf->dev, "USB hub found\n");
857
858 hub = kmalloc(sizeof(*hub), GFP_KERNEL);
859 if (!hub) {
860 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
861 return -ENOMEM;
862 }
863
864 memset(hub, 0, sizeof(*hub));
865
866 INIT_LIST_HEAD(&hub->event_list);
867 hub->intfdev = &intf->dev;
868 hub->hdev = hdev;
869 INIT_WORK(&hub->leds, led_work, hub);
870
871 usb_set_intfdata (intf, hub);
872
873 if (hdev->speed == USB_SPEED_HIGH)
874 highspeed_hubs++;
875
876 if (hub_configure(hub, endpoint) >= 0)
877 return 0;
878
879 hub_disconnect (intf);
880 return -ENODEV;
881 }
882
883 static int
884 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
885 {
886 struct usb_device *hdev = interface_to_usbdev (intf);
887
888 /* assert ifno == 0 (part of hub spec) */
889 switch (code) {
890 case USBDEVFS_HUB_PORTINFO: {
891 struct usbdevfs_hub_portinfo *info = user_data;
892 int i;
893
894 spin_lock_irq(&device_state_lock);
895 if (hdev->devnum <= 0)
896 info->nports = 0;
897 else {
898 info->nports = hdev->maxchild;
899 for (i = 0; i < info->nports; i++) {
900 if (hdev->children[i] == NULL)
901 info->port[i] = 0;
902 else
903 info->port[i] =
904 hdev->children[i]->devnum;
905 }
906 }
907 spin_unlock_irq(&device_state_lock);
908
909 return info->nports + 1;
910 }
911
912 default:
913 return -ENOSYS;
914 }
915 }
916
917 /* caller has locked the hub device */
918 static void hub_pre_reset(struct usb_hub *hub)
919 {
920 struct usb_device *hdev = hub->hdev;
921 int i;
922
923 for (i = 0; i < hdev->maxchild; ++i) {
924 if (hdev->children[i])
925 usb_disconnect(&hdev->children[i]);
926 }
927 hub_quiesce(hub);
928 }
929
930 /* caller has locked the hub device */
931 static void hub_post_reset(struct usb_hub *hub)
932 {
933 hub_activate(hub);
934 hub_power_on(hub);
935 }
936
937
938 /* grab device/port lock, returning index of that port (zero based).
939 * protects the upstream link used by this device from concurrent
940 * tree operations like suspend, resume, reset, and disconnect, which
941 * apply to everything downstream of a given port.
942 */
943 static int locktree(struct usb_device *udev)
944 {
945 int t;
946 struct usb_device *hdev;
947
948 if (!udev)
949 return -ENODEV;
950
951 /* root hub is always the first lock in the series */
952 hdev = udev->parent;
953 if (!hdev) {
954 usb_lock_device(udev);
955 return 0;
956 }
957
958 /* on the path from root to us, lock everything from
959 * top down, dropping parent locks when not needed
960 */
961 t = locktree(hdev);
962 if (t < 0)
963 return t;
964 for (t = 0; t < hdev->maxchild; t++) {
965 if (hdev->children[t] == udev) {
966 /* everything is fail-fast once disconnect
967 * processing starts
968 */
969 if (udev->state == USB_STATE_NOTATTACHED)
970 break;
971
972 /* when everyone grabs locks top->bottom,
973 * non-overlapping work may be concurrent
974 */
975 down(&udev->serialize);
976 up(&hdev->serialize);
977 return t + 1;
978 }
979 }
980 usb_unlock_device(hdev);
981 return -ENODEV;
982 }
983
984 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
985 {
986 int i;
987
988 for (i = 0; i < udev->maxchild; ++i) {
989 if (udev->children[i])
990 recursively_mark_NOTATTACHED(udev->children[i]);
991 }
992 udev->state = USB_STATE_NOTATTACHED;
993 }
994
995 /**
996 * usb_set_device_state - change a device's current state (usbcore, hcds)
997 * @udev: pointer to device whose state should be changed
998 * @new_state: new state value to be stored
999 *
1000 * udev->state is _not_ fully protected by the device lock. Although
1001 * most transitions are made only while holding the lock, the state can
1002 * can change to USB_STATE_NOTATTACHED at almost any time. This
1003 * is so that devices can be marked as disconnected as soon as possible,
1004 * without having to wait for any semaphores to be released. As a result,
1005 * all changes to any device's state must be protected by the
1006 * device_state_lock spinlock.
1007 *
1008 * Once a device has been added to the device tree, all changes to its state
1009 * should be made using this routine. The state should _not_ be set directly.
1010 *
1011 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1012 * Otherwise udev->state is set to new_state, and if new_state is
1013 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1014 * to USB_STATE_NOTATTACHED.
1015 */
1016 void usb_set_device_state(struct usb_device *udev,
1017 enum usb_device_state new_state)
1018 {
1019 unsigned long flags;
1020
1021 spin_lock_irqsave(&device_state_lock, flags);
1022 if (udev->state == USB_STATE_NOTATTACHED)
1023 ; /* do nothing */
1024 else if (new_state != USB_STATE_NOTATTACHED) {
1025 udev->state = new_state;
1026 if (new_state == USB_STATE_CONFIGURED)
1027 device_init_wakeup(&udev->dev,
1028 (udev->actconfig->desc.bmAttributes
1029 & USB_CONFIG_ATT_WAKEUP));
1030 else if (new_state != USB_STATE_SUSPENDED)
1031 device_init_wakeup(&udev->dev, 0);
1032 } else
1033 recursively_mark_NOTATTACHED(udev);
1034 spin_unlock_irqrestore(&device_state_lock, flags);
1035 }
1036 EXPORT_SYMBOL(usb_set_device_state);
1037
1038
1039 static void choose_address(struct usb_device *udev)
1040 {
1041 int devnum;
1042 struct usb_bus *bus = udev->bus;
1043
1044 /* If khubd ever becomes multithreaded, this will need a lock */
1045
1046 /* Try to allocate the next devnum beginning at bus->devnum_next. */
1047 devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1048 bus->devnum_next);
1049 if (devnum >= 128)
1050 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1051
1052 bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1053
1054 if (devnum < 128) {
1055 set_bit(devnum, bus->devmap.devicemap);
1056 udev->devnum = devnum;
1057 }
1058 }
1059
1060 static void release_address(struct usb_device *udev)
1061 {
1062 if (udev->devnum > 0) {
1063 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1064 udev->devnum = -1;
1065 }
1066 }
1067
1068 /**
1069 * usb_disconnect - disconnect a device (usbcore-internal)
1070 * @pdev: pointer to device being disconnected
1071 * Context: !in_interrupt ()
1072 *
1073 * Something got disconnected. Get rid of it and all of its children.
1074 *
1075 * If *pdev is a normal device then the parent hub must already be locked.
1076 * If *pdev is a root hub then this routine will acquire the
1077 * usb_bus_list_lock on behalf of the caller.
1078 *
1079 * Only hub drivers (including virtual root hub drivers for host
1080 * controllers) should ever call this.
1081 *
1082 * This call is synchronous, and may not be used in an interrupt context.
1083 */
1084 void usb_disconnect(struct usb_device **pdev)
1085 {
1086 struct usb_device *udev = *pdev;
1087 int i;
1088
1089 if (!udev) {
1090 pr_debug ("%s nodev\n", __FUNCTION__);
1091 return;
1092 }
1093
1094 /* mark the device as inactive, so any further urb submissions for
1095 * this device (and any of its children) will fail immediately.
1096 * this quiesces everyting except pending urbs.
1097 */
1098 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1099
1100 /* lock the bus list on behalf of HCDs unregistering their root hubs */
1101 if (!udev->parent) {
1102 down(&usb_bus_list_lock);
1103 usb_lock_device(udev);
1104 } else
1105 down(&udev->serialize);
1106
1107 dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1108
1109 /* Free up all the children before we remove this device */
1110 for (i = 0; i < USB_MAXCHILDREN; i++) {
1111 if (udev->children[i])
1112 usb_disconnect(&udev->children[i]);
1113 }
1114
1115 /* deallocate hcd/hardware state ... nuking all pending urbs and
1116 * cleaning up all state associated with the current configuration
1117 * so that the hardware is now fully quiesced.
1118 */
1119 usb_disable_device(udev, 0);
1120
1121 /* Free the device number, remove the /proc/bus/usb entry and
1122 * the sysfs attributes, and delete the parent's children[]
1123 * (or root_hub) pointer.
1124 */
1125 dev_dbg (&udev->dev, "unregistering device\n");
1126 release_address(udev);
1127 usbfs_remove_device(udev);
1128 usbdev_remove(udev);
1129 usb_remove_sysfs_dev_files(udev);
1130
1131 /* Avoid races with recursively_mark_NOTATTACHED() */
1132 spin_lock_irq(&device_state_lock);
1133 *pdev = NULL;
1134 spin_unlock_irq(&device_state_lock);
1135
1136 if (!udev->parent) {
1137 usb_unlock_device(udev);
1138 up(&usb_bus_list_lock);
1139 } else
1140 up(&udev->serialize);
1141
1142 device_unregister(&udev->dev);
1143 }
1144
1145 static int choose_configuration(struct usb_device *udev)
1146 {
1147 int c, i;
1148
1149 /* NOTE: this should interact with hub power budgeting */
1150
1151 c = udev->config[0].desc.bConfigurationValue;
1152 if (udev->descriptor.bNumConfigurations != 1) {
1153 for (i = 0; i < udev->descriptor.bNumConfigurations; i++) {
1154 struct usb_interface_descriptor *desc;
1155
1156 /* heuristic: Linux is more likely to have class
1157 * drivers, so avoid vendor-specific interfaces.
1158 */
1159 desc = &udev->config[i].intf_cache[0]
1160 ->altsetting->desc;
1161 if (desc->bInterfaceClass == USB_CLASS_VENDOR_SPEC)
1162 continue;
1163 /* COMM/2/all is CDC ACM, except 0xff is MSFT RNDIS.
1164 * MSFT needs this to be the first config; never use
1165 * it as the default unless Linux has host-side RNDIS.
1166 * A second config would ideally be CDC-Ethernet, but
1167 * may instead be the "vendor specific" CDC subset
1168 * long used by ARM Linux for sa1100 or pxa255.
1169 */
1170 if (desc->bInterfaceClass == USB_CLASS_COMM
1171 && desc->bInterfaceSubClass == 2
1172 && desc->bInterfaceProtocol == 0xff) {
1173 c = udev->config[1].desc.bConfigurationValue;
1174 continue;
1175 }
1176 c = udev->config[i].desc.bConfigurationValue;
1177 break;
1178 }
1179 dev_info(&udev->dev,
1180 "configuration #%d chosen from %d choices\n",
1181 c, udev->descriptor.bNumConfigurations);
1182 }
1183 return c;
1184 }
1185
1186 #ifdef DEBUG
1187 static void show_string(struct usb_device *udev, char *id, char *string)
1188 {
1189 if (!string)
1190 return;
1191 dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1192 }
1193
1194 #else
1195 static inline void show_string(struct usb_device *udev, char *id, char *string)
1196 {}
1197 #endif
1198
1199 static void get_string(struct usb_device *udev, char **string, int index)
1200 {
1201 char *buf;
1202
1203 if (!index)
1204 return;
1205 buf = kmalloc(256, GFP_KERNEL);
1206 if (!buf)
1207 return;
1208 if (usb_string(udev, index, buf, 256) > 0)
1209 *string = buf;
1210 else
1211 kfree(buf);
1212 }
1213
1214
1215 #ifdef CONFIG_USB_OTG
1216 #include "otg_whitelist.h"
1217 #endif
1218
1219 /**
1220 * usb_new_device - perform initial device setup (usbcore-internal)
1221 * @udev: newly addressed device (in ADDRESS state)
1222 *
1223 * This is called with devices which have been enumerated, but not yet
1224 * configured. The device descriptor is available, but not descriptors
1225 * for any device configuration. The caller must have locked udev and
1226 * either the parent hub (if udev is a normal device) or else the
1227 * usb_bus_list_lock (if udev is a root hub). The parent's pointer to
1228 * udev has already been installed, but udev is not yet visible through
1229 * sysfs or other filesystem code.
1230 *
1231 * Returns 0 for success (device is configured and listed, with its
1232 * interfaces, in sysfs); else a negative errno value.
1233 *
1234 * This call is synchronous, and may not be used in an interrupt context.
1235 *
1236 * Only the hub driver should ever call this; root hub registration
1237 * uses it indirectly.
1238 */
1239 int usb_new_device(struct usb_device *udev)
1240 {
1241 int err;
1242 int c;
1243
1244 err = usb_get_configuration(udev);
1245 if (err < 0) {
1246 dev_err(&udev->dev, "can't read configurations, error %d\n",
1247 err);
1248 goto fail;
1249 }
1250
1251 /* read the standard strings and cache them if present */
1252 get_string(udev, &udev->product, udev->descriptor.iProduct);
1253 get_string(udev, &udev->manufacturer, udev->descriptor.iManufacturer);
1254 get_string(udev, &udev->serial, udev->descriptor.iSerialNumber);
1255
1256 /* Tell the world! */
1257 dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1258 "SerialNumber=%d\n",
1259 udev->descriptor.iManufacturer,
1260 udev->descriptor.iProduct,
1261 udev->descriptor.iSerialNumber);
1262 show_string(udev, "Product", udev->product);
1263 show_string(udev, "Manufacturer", udev->manufacturer);
1264 show_string(udev, "SerialNumber", udev->serial);
1265
1266 #ifdef CONFIG_USB_OTG
1267 /*
1268 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1269 * to wake us after we've powered off VBUS; and HNP, switching roles
1270 * "host" to "peripheral". The OTG descriptor helps figure this out.
1271 */
1272 if (!udev->bus->is_b_host
1273 && udev->config
1274 && udev->parent == udev->bus->root_hub) {
1275 struct usb_otg_descriptor *desc = 0;
1276 struct usb_bus *bus = udev->bus;
1277
1278 /* descriptor may appear anywhere in config */
1279 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1280 le16_to_cpu(udev->config[0].desc.wTotalLength),
1281 USB_DT_OTG, (void **) &desc) == 0) {
1282 if (desc->bmAttributes & USB_OTG_HNP) {
1283 unsigned port1;
1284 struct usb_device *root = udev->parent;
1285
1286 for (port1 = 1; port1 <= root->maxchild;
1287 port1++) {
1288 if (root->children[port1-1] == udev)
1289 break;
1290 }
1291
1292 dev_info(&udev->dev,
1293 "Dual-Role OTG device on %sHNP port\n",
1294 (port1 == bus->otg_port)
1295 ? "" : "non-");
1296
1297 /* enable HNP before suspend, it's simpler */
1298 if (port1 == bus->otg_port)
1299 bus->b_hnp_enable = 1;
1300 err = usb_control_msg(udev,
1301 usb_sndctrlpipe(udev, 0),
1302 USB_REQ_SET_FEATURE, 0,
1303 bus->b_hnp_enable
1304 ? USB_DEVICE_B_HNP_ENABLE
1305 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1306 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1307 if (err < 0) {
1308 /* OTG MESSAGE: report errors here,
1309 * customize to match your product.
1310 */
1311 dev_info(&udev->dev,
1312 "can't set HNP mode; %d\n",
1313 err);
1314 bus->b_hnp_enable = 0;
1315 }
1316 }
1317 }
1318 }
1319
1320 if (!is_targeted(udev)) {
1321
1322 /* Maybe it can talk to us, though we can't talk to it.
1323 * (Includes HNP test device.)
1324 */
1325 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1326 static int __usb_suspend_device(struct usb_device *,
1327 int port1);
1328 err = __usb_suspend_device(udev, udev->bus->otg_port);
1329 if (err < 0)
1330 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1331 }
1332 err = -ENODEV;
1333 goto fail;
1334 }
1335 #endif
1336
1337 /* put device-specific files into sysfs */
1338 err = device_add (&udev->dev);
1339 if (err) {
1340 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1341 goto fail;
1342 }
1343 usb_create_sysfs_dev_files (udev);
1344
1345 /* choose and set the configuration. that registers the interfaces
1346 * with the driver core, and lets usb device drivers bind to them.
1347 */
1348 c = choose_configuration(udev);
1349 if (c < 0)
1350 dev_warn(&udev->dev,
1351 "can't choose an initial configuration\n");
1352 else {
1353 err = usb_set_configuration(udev, c);
1354 if (err) {
1355 dev_err(&udev->dev, "can't set config #%d, error %d\n",
1356 c, err);
1357 usb_remove_sysfs_dev_files(udev);
1358 device_del(&udev->dev);
1359 goto fail;
1360 }
1361 }
1362
1363 /* USB device state == configured ... usable */
1364
1365 /* add a /proc/bus/usb entry */
1366 usbdev_add(udev);
1367 usbfs_add_device(udev);
1368 return 0;
1369
1370 fail:
1371 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1372 return err;
1373 }
1374
1375
1376 static int hub_port_status(struct usb_hub *hub, int port1,
1377 u16 *status, u16 *change)
1378 {
1379 int ret;
1380
1381 ret = get_port_status(hub->hdev, port1, &hub->status->port);
1382 if (ret < 0)
1383 dev_err (hub->intfdev,
1384 "%s failed (err = %d)\n", __FUNCTION__, ret);
1385 else {
1386 *status = le16_to_cpu(hub->status->port.wPortStatus);
1387 *change = le16_to_cpu(hub->status->port.wPortChange);
1388 ret = 0;
1389 }
1390 return ret;
1391 }
1392
1393 #define PORT_RESET_TRIES 5
1394 #define SET_ADDRESS_TRIES 2
1395 #define GET_DESCRIPTOR_TRIES 2
1396 #define SET_CONFIG_TRIES (2 * (use_both_schemes + 1))
1397 #define USE_NEW_SCHEME(i) ((i) / 2 == old_scheme_first)
1398
1399 #define HUB_ROOT_RESET_TIME 50 /* times are in msec */
1400 #define HUB_SHORT_RESET_TIME 10
1401 #define HUB_LONG_RESET_TIME 200
1402 #define HUB_RESET_TIMEOUT 500
1403
1404 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1405 struct usb_device *udev, unsigned int delay)
1406 {
1407 int delay_time, ret;
1408 u16 portstatus;
1409 u16 portchange;
1410
1411 for (delay_time = 0;
1412 delay_time < HUB_RESET_TIMEOUT;
1413 delay_time += delay) {
1414 /* wait to give the device a chance to reset */
1415 msleep(delay);
1416
1417 /* read and decode port status */
1418 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1419 if (ret < 0)
1420 return ret;
1421
1422 /* Device went away? */
1423 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1424 return -ENOTCONN;
1425
1426 /* bomb out completely if something weird happened */
1427 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1428 return -EINVAL;
1429
1430 /* if we`ve finished resetting, then break out of the loop */
1431 if (!(portstatus & USB_PORT_STAT_RESET) &&
1432 (portstatus & USB_PORT_STAT_ENABLE)) {
1433 if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1434 udev->speed = USB_SPEED_HIGH;
1435 else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1436 udev->speed = USB_SPEED_LOW;
1437 else
1438 udev->speed = USB_SPEED_FULL;
1439 return 0;
1440 }
1441
1442 /* switch to the long delay after two short delay failures */
1443 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1444 delay = HUB_LONG_RESET_TIME;
1445
1446 dev_dbg (hub->intfdev,
1447 "port %d not reset yet, waiting %dms\n",
1448 port1, delay);
1449 }
1450
1451 return -EBUSY;
1452 }
1453
1454 static int hub_port_reset(struct usb_hub *hub, int port1,
1455 struct usb_device *udev, unsigned int delay)
1456 {
1457 int i, status;
1458
1459 /* Reset the port */
1460 for (i = 0; i < PORT_RESET_TRIES; i++) {
1461 status = set_port_feature(hub->hdev,
1462 port1, USB_PORT_FEAT_RESET);
1463 if (status)
1464 dev_err(hub->intfdev,
1465 "cannot reset port %d (err = %d)\n",
1466 port1, status);
1467 else {
1468 status = hub_port_wait_reset(hub, port1, udev, delay);
1469 if (status && status != -ENOTCONN)
1470 dev_dbg(hub->intfdev,
1471 "port_wait_reset: err = %d\n",
1472 status);
1473 }
1474
1475 /* return on disconnect or reset */
1476 switch (status) {
1477 case 0:
1478 /* TRSTRCY = 10 ms; plus some extra */
1479 msleep(10 + 40);
1480 /* FALL THROUGH */
1481 case -ENOTCONN:
1482 case -ENODEV:
1483 clear_port_feature(hub->hdev,
1484 port1, USB_PORT_FEAT_C_RESET);
1485 /* FIXME need disconnect() for NOTATTACHED device */
1486 usb_set_device_state(udev, status
1487 ? USB_STATE_NOTATTACHED
1488 : USB_STATE_DEFAULT);
1489 return status;
1490 }
1491
1492 dev_dbg (hub->intfdev,
1493 "port %d not enabled, trying reset again...\n",
1494 port1);
1495 delay = HUB_LONG_RESET_TIME;
1496 }
1497
1498 dev_err (hub->intfdev,
1499 "Cannot enable port %i. Maybe the USB cable is bad?\n",
1500 port1);
1501
1502 return status;
1503 }
1504
1505 /*
1506 * Disable a port and mark a logical connnect-change event, so that some
1507 * time later khubd will disconnect() any existing usb_device on the port
1508 * and will re-enumerate if there actually is a device attached.
1509 */
1510 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1511 {
1512 dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1513 hub_port_disable(hub, port1, 1);
1514
1515 /* FIXME let caller ask to power down the port:
1516 * - some devices won't enumerate without a VBUS power cycle
1517 * - SRP saves power that way
1518 * - ... new call, TBD ...
1519 * That's easy if this hub can switch power per-port, and
1520 * khubd reactivates the port later (timer, SRP, etc).
1521 * Powerdown must be optional, because of reset/DFU.
1522 */
1523
1524 set_bit(port1, hub->change_bits);
1525 kick_khubd(hub);
1526 }
1527
1528
1529 #ifdef CONFIG_USB_SUSPEND
1530
1531 /*
1532 * Selective port suspend reduces power; most suspended devices draw
1533 * less than 500 uA. It's also used in OTG, along with remote wakeup.
1534 * All devices below the suspended port are also suspended.
1535 *
1536 * Devices leave suspend state when the host wakes them up. Some devices
1537 * also support "remote wakeup", where the device can activate the USB
1538 * tree above them to deliver data, such as a keypress or packet. In
1539 * some cases, this wakes the USB host.
1540 */
1541 static int hub_port_suspend(struct usb_hub *hub, int port1,
1542 struct usb_device *udev)
1543 {
1544 int status;
1545
1546 // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1547
1548 /* enable remote wakeup when appropriate; this lets the device
1549 * wake up the upstream hub (including maybe the root hub).
1550 *
1551 * NOTE: OTG devices may issue remote wakeup (or SRP) even when
1552 * we don't explicitly enable it here.
1553 */
1554 if (device_may_wakeup(&udev->dev)) {
1555 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1556 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1557 USB_DEVICE_REMOTE_WAKEUP, 0,
1558 NULL, 0,
1559 USB_CTRL_SET_TIMEOUT);
1560 if (status)
1561 dev_dbg(&udev->dev,
1562 "won't remote wakeup, status %d\n",
1563 status);
1564 }
1565
1566 /* see 7.1.7.6 */
1567 status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1568 if (status) {
1569 dev_dbg(hub->intfdev,
1570 "can't suspend port %d, status %d\n",
1571 port1, status);
1572 /* paranoia: "should not happen" */
1573 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1574 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1575 USB_DEVICE_REMOTE_WAKEUP, 0,
1576 NULL, 0,
1577 USB_CTRL_SET_TIMEOUT);
1578 } else {
1579 /* device has up to 10 msec to fully suspend */
1580 dev_dbg(&udev->dev, "usb suspend\n");
1581 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1582 msleep(10);
1583 }
1584 return status;
1585 }
1586
1587 /*
1588 * Devices on USB hub ports have only one "suspend" state, corresponding
1589 * to ACPI D2, "may cause the device to lose some context".
1590 * State transitions include:
1591 *
1592 * - suspend, resume ... when the VBUS power link stays live
1593 * - suspend, disconnect ... VBUS lost
1594 *
1595 * Once VBUS drop breaks the circuit, the port it's using has to go through
1596 * normal re-enumeration procedures, starting with enabling VBUS power.
1597 * Other than re-initializing the hub (plug/unplug, except for root hubs),
1598 * Linux (2.6) currently has NO mechanisms to initiate that: no khubd
1599 * timer, no SRP, no requests through sysfs.
1600 *
1601 * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1602 * the root hub for their bus goes into global suspend ... so we don't
1603 * (falsely) update the device power state to say it suspended.
1604 */
1605 static int __usb_suspend_device (struct usb_device *udev, int port1)
1606 {
1607 int status;
1608
1609 /* caller owns the udev device lock */
1610 if (port1 < 0)
1611 return port1;
1612
1613 if (udev->state == USB_STATE_SUSPENDED
1614 || udev->state == USB_STATE_NOTATTACHED) {
1615 return 0;
1616 }
1617
1618 /* all interfaces must already be suspended */
1619 if (udev->actconfig) {
1620 int i;
1621
1622 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1623 struct usb_interface *intf;
1624
1625 intf = udev->actconfig->interface[i];
1626 if (is_active(intf)) {
1627 dev_dbg(&intf->dev, "nyet suspended\n");
1628 return -EBUSY;
1629 }
1630 }
1631 }
1632
1633 /* "global suspend" of the HC-to-USB interface (root hub), or
1634 * "selective suspend" of just one hub-device link.
1635 */
1636 if (!udev->parent) {
1637 struct usb_bus *bus = udev->bus;
1638 if (bus && bus->op->hub_suspend) {
1639 status = bus->op->hub_suspend (bus);
1640 if (status == 0) {
1641 dev_dbg(&udev->dev, "usb suspend\n");
1642 usb_set_device_state(udev,
1643 USB_STATE_SUSPENDED);
1644 }
1645 } else
1646 status = -EOPNOTSUPP;
1647 } else
1648 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1649 udev);
1650
1651 if (status == 0)
1652 udev->dev.power.power_state = PMSG_SUSPEND;
1653 return status;
1654 }
1655
1656 /**
1657 * usb_suspend_device - suspend a usb device
1658 * @udev: device that's no longer in active use
1659 * Context: must be able to sleep; device not locked
1660 *
1661 * Suspends a USB device that isn't in active use, conserving power.
1662 * Devices may wake out of a suspend, if anything important happens,
1663 * using the remote wakeup mechanism. They may also be taken out of
1664 * suspend by the host, using usb_resume_device(). It's also routine
1665 * to disconnect devices while they are suspended.
1666 *
1667 * This only affects the USB hardware for a device; its interfaces
1668 * (and, for hubs, child devices) must already have been suspended.
1669 *
1670 * Suspending OTG devices may trigger HNP, if that's been enabled
1671 * between a pair of dual-role devices. That will change roles, such
1672 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1673 *
1674 * Returns 0 on success, else negative errno.
1675 */
1676 int usb_suspend_device(struct usb_device *udev)
1677 {
1678 int port1, status;
1679
1680 port1 = locktree(udev);
1681 if (port1 < 0)
1682 return port1;
1683
1684 status = __usb_suspend_device(udev, port1);
1685 usb_unlock_device(udev);
1686 return status;
1687 }
1688
1689 /*
1690 * If the USB "suspend" state is in use (rather than "global suspend"),
1691 * many devices will be individually taken out of suspend state using
1692 * special" resume" signaling. These routines kick in shortly after
1693 * hardware resume signaling is finished, either because of selective
1694 * resume (by host) or remote wakeup (by device) ... now see what changed
1695 * in the tree that's rooted at this device.
1696 */
1697 static int finish_port_resume(struct usb_device *udev)
1698 {
1699 int status;
1700 u16 devstatus;
1701
1702 /* caller owns the udev device lock */
1703 dev_dbg(&udev->dev, "usb resume\n");
1704
1705 /* usb ch9 identifies four variants of SUSPENDED, based on what
1706 * state the device resumes to. Linux currently won't see the
1707 * first two on the host side; they'd be inside hub_port_init()
1708 * during many timeouts, but khubd can't suspend until later.
1709 */
1710 usb_set_device_state(udev, udev->actconfig
1711 ? USB_STATE_CONFIGURED
1712 : USB_STATE_ADDRESS);
1713 udev->dev.power.power_state = PMSG_ON;
1714
1715 /* 10.5.4.5 says be sure devices in the tree are still there.
1716 * For now let's assume the device didn't go crazy on resume,
1717 * and device drivers will know about any resume quirks.
1718 */
1719 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1720 if (status < 0)
1721 dev_dbg(&udev->dev,
1722 "gone after usb resume? status %d\n",
1723 status);
1724 else if (udev->actconfig) {
1725 unsigned i;
1726 int (*resume)(struct device *);
1727
1728 le16_to_cpus(&devstatus);
1729 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
1730 status = usb_control_msg(udev,
1731 usb_sndctrlpipe(udev, 0),
1732 USB_REQ_CLEAR_FEATURE,
1733 USB_RECIP_DEVICE,
1734 USB_DEVICE_REMOTE_WAKEUP, 0,
1735 NULL, 0,
1736 USB_CTRL_SET_TIMEOUT);
1737 if (status) {
1738 dev_dbg(&udev->dev, "disable remote "
1739 "wakeup, status %d\n", status);
1740 status = 0;
1741 }
1742 }
1743
1744 /* resume interface drivers; if this is a hub, it
1745 * may have a child resume event to deal with soon
1746 */
1747 resume = udev->dev.bus->resume;
1748 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++)
1749 (void) resume(&udev->actconfig->interface[i]->dev);
1750 status = 0;
1751
1752 } else if (udev->devnum <= 0) {
1753 dev_dbg(&udev->dev, "bogus resume!\n");
1754 status = -EINVAL;
1755 }
1756 return status;
1757 }
1758
1759 static int
1760 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1761 {
1762 int status;
1763
1764 // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1765
1766 /* see 7.1.7.7; affects power usage, but not budgeting */
1767 status = clear_port_feature(hub->hdev,
1768 port1, USB_PORT_FEAT_SUSPEND);
1769 if (status) {
1770 dev_dbg(hub->intfdev,
1771 "can't resume port %d, status %d\n",
1772 port1, status);
1773 } else {
1774 u16 devstatus;
1775 u16 portchange;
1776
1777 /* drive resume for at least 20 msec */
1778 if (udev)
1779 dev_dbg(&udev->dev, "RESUME\n");
1780 msleep(25);
1781
1782 #define LIVE_FLAGS ( USB_PORT_STAT_POWER \
1783 | USB_PORT_STAT_ENABLE \
1784 | USB_PORT_STAT_CONNECTION)
1785
1786 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1787 * stop resume signaling. Then finish the resume
1788 * sequence.
1789 */
1790 devstatus = portchange = 0;
1791 status = hub_port_status(hub, port1,
1792 &devstatus, &portchange);
1793 if (status < 0
1794 || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
1795 || (devstatus & USB_PORT_STAT_SUSPEND) != 0
1796 ) {
1797 dev_dbg(hub->intfdev,
1798 "port %d status %04x.%04x after resume, %d\n",
1799 port1, portchange, devstatus, status);
1800 } else {
1801 /* TRSMRCY = 10 msec */
1802 msleep(10);
1803 if (udev)
1804 status = finish_port_resume(udev);
1805 }
1806 }
1807 if (status < 0)
1808 hub_port_logical_disconnect(hub, port1);
1809
1810 return status;
1811 }
1812
1813 static int hub_resume (struct usb_interface *intf);
1814
1815 /**
1816 * usb_resume_device - re-activate a suspended usb device
1817 * @udev: device to re-activate
1818 * Context: must be able to sleep; device not locked
1819 *
1820 * This will re-activate the suspended device, increasing power usage
1821 * while letting drivers communicate again with its endpoints.
1822 * USB resume explicitly guarantees that the power session between
1823 * the host and the device is the same as it was when the device
1824 * suspended.
1825 *
1826 * Returns 0 on success, else negative errno.
1827 */
1828 int usb_resume_device(struct usb_device *udev)
1829 {
1830 int port1, status;
1831
1832 port1 = locktree(udev);
1833 if (port1 < 0)
1834 return port1;
1835
1836 /* "global resume" of the HC-to-USB interface (root hub), or
1837 * selective resume of one hub-to-device port
1838 */
1839 if (!udev->parent) {
1840 struct usb_bus *bus = udev->bus;
1841 if (bus && bus->op->hub_resume) {
1842 status = bus->op->hub_resume (bus);
1843 } else
1844 status = -EOPNOTSUPP;
1845 if (status == 0) {
1846 dev_dbg(&udev->dev, "usb resume\n");
1847 /* TRSMRCY = 10 msec */
1848 msleep(10);
1849 usb_set_device_state (udev, USB_STATE_CONFIGURED);
1850 udev->dev.power.power_state = PMSG_ON;
1851 status = hub_resume (udev
1852 ->actconfig->interface[0]);
1853 }
1854 } else if (udev->state == USB_STATE_SUSPENDED) {
1855 // NOTE this fails if parent is also suspended...
1856 status = hub_port_resume(hdev_to_hub(udev->parent),
1857 port1, udev);
1858 } else {
1859 status = 0;
1860 }
1861 if (status < 0) {
1862 dev_dbg(&udev->dev, "can't resume, status %d\n",
1863 status);
1864 }
1865
1866 usb_unlock_device(udev);
1867
1868 /* rebind drivers that had no suspend() */
1869 if (status == 0) {
1870 usb_lock_all_devices();
1871 bus_rescan_devices(&usb_bus_type);
1872 usb_unlock_all_devices();
1873 }
1874 return status;
1875 }
1876
1877 static int remote_wakeup(struct usb_device *udev)
1878 {
1879 int status = 0;
1880
1881 /* don't repeat RESUME sequence if this device
1882 * was already woken up by some other task
1883 */
1884 down(&udev->serialize);
1885 if (udev->state == USB_STATE_SUSPENDED) {
1886 dev_dbg(&udev->dev, "RESUME (wakeup)\n");
1887 /* TRSMRCY = 10 msec */
1888 msleep(10);
1889 status = finish_port_resume(udev);
1890 }
1891 up(&udev->serialize);
1892 return status;
1893 }
1894
1895 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
1896 {
1897 struct usb_hub *hub = usb_get_intfdata (intf);
1898 struct usb_device *hdev = hub->hdev;
1899 unsigned port1;
1900
1901 /* fail if children aren't already suspended */
1902 for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1903 struct usb_device *udev;
1904
1905 udev = hdev->children [port1-1];
1906 if (udev && udev->state != USB_STATE_SUSPENDED) {
1907 dev_dbg(&intf->dev, "port %d nyet suspended\n", port1);
1908 return -EBUSY;
1909 }
1910 }
1911
1912 /* stop khubd and related activity */
1913 hub_quiesce(hub);
1914 return 0;
1915 }
1916
1917 static int hub_resume(struct usb_interface *intf)
1918 {
1919 struct usb_device *hdev = interface_to_usbdev(intf);
1920 struct usb_hub *hub = usb_get_intfdata (intf);
1921 unsigned port1;
1922 int status;
1923
1924 for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1925 struct usb_device *udev;
1926 u16 portstat, portchange;
1927
1928 udev = hdev->children [port1-1];
1929 status = hub_port_status(hub, port1, &portstat, &portchange);
1930 if (status == 0) {
1931 if (portchange & USB_PORT_STAT_C_SUSPEND) {
1932 clear_port_feature(hdev, port1,
1933 USB_PORT_FEAT_C_SUSPEND);
1934 portchange &= ~USB_PORT_STAT_C_SUSPEND;
1935 }
1936
1937 /* let khubd handle disconnects etc */
1938 if (portchange)
1939 continue;
1940 }
1941
1942 if (!udev || status < 0)
1943 continue;
1944 down (&udev->serialize);
1945 if (portstat & USB_PORT_STAT_SUSPEND)
1946 status = hub_port_resume(hub, port1, udev);
1947 else {
1948 status = finish_port_resume(udev);
1949 if (status < 0) {
1950 dev_dbg(&intf->dev, "resume port %d --> %d\n",
1951 port1, status);
1952 hub_port_logical_disconnect(hub, port1);
1953 }
1954 }
1955 up(&udev->serialize);
1956 }
1957 hub->resume_root_hub = 0;
1958 hub_activate(hub);
1959 return 0;
1960 }
1961
1962 void usb_resume_root_hub(struct usb_device *hdev)
1963 {
1964 struct usb_hub *hub = hdev_to_hub(hdev);
1965
1966 hub->resume_root_hub = 1;
1967 kick_khubd(hub);
1968 }
1969
1970 #else /* !CONFIG_USB_SUSPEND */
1971
1972 int usb_suspend_device(struct usb_device *udev)
1973 {
1974 /* state does NOT lie by saying it's USB_STATE_SUSPENDED! */
1975 return 0;
1976 }
1977
1978 int usb_resume_device(struct usb_device *udev)
1979 {
1980 udev->dev.power_state.event = PM_EVENT_ON;
1981 return 0;
1982 }
1983
1984 #define hub_suspend NULL
1985 #define hub_resume NULL
1986 #define remote_wakeup(x) 0
1987
1988 #endif /* CONFIG_USB_SUSPEND */
1989
1990 EXPORT_SYMBOL(usb_suspend_device);
1991 EXPORT_SYMBOL(usb_resume_device);
1992
1993
1994
1995 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
1996 *
1997 * Between connect detection and reset signaling there must be a delay
1998 * of 100ms at least for debounce and power-settling. The corresponding
1999 * timer shall restart whenever the downstream port detects a disconnect.
2000 *
2001 * Apparently there are some bluetooth and irda-dongles and a number of
2002 * low-speed devices for which this debounce period may last over a second.
2003 * Not covered by the spec - but easy to deal with.
2004 *
2005 * This implementation uses a 1500ms total debounce timeout; if the
2006 * connection isn't stable by then it returns -ETIMEDOUT. It checks
2007 * every 25ms for transient disconnects. When the port status has been
2008 * unchanged for 100ms it returns the port status.
2009 */
2010
2011 #define HUB_DEBOUNCE_TIMEOUT 1500
2012 #define HUB_DEBOUNCE_STEP 25
2013 #define HUB_DEBOUNCE_STABLE 100
2014
2015 static int hub_port_debounce(struct usb_hub *hub, int port1)
2016 {
2017 int ret;
2018 int total_time, stable_time = 0;
2019 u16 portchange, portstatus;
2020 unsigned connection = 0xffff;
2021
2022 for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2023 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2024 if (ret < 0)
2025 return ret;
2026
2027 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2028 (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2029 stable_time += HUB_DEBOUNCE_STEP;
2030 if (stable_time >= HUB_DEBOUNCE_STABLE)
2031 break;
2032 } else {
2033 stable_time = 0;
2034 connection = portstatus & USB_PORT_STAT_CONNECTION;
2035 }
2036
2037 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2038 clear_port_feature(hub->hdev, port1,
2039 USB_PORT_FEAT_C_CONNECTION);
2040 }
2041
2042 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2043 break;
2044 msleep(HUB_DEBOUNCE_STEP);
2045 }
2046
2047 dev_dbg (hub->intfdev,
2048 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2049 port1, total_time, stable_time, portstatus);
2050
2051 if (stable_time < HUB_DEBOUNCE_STABLE)
2052 return -ETIMEDOUT;
2053 return portstatus;
2054 }
2055
2056 static void ep0_reinit(struct usb_device *udev)
2057 {
2058 usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2059 usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2060 udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2061 }
2062
2063 #define usb_sndaddr0pipe() (PIPE_CONTROL << 30)
2064 #define usb_rcvaddr0pipe() ((PIPE_CONTROL << 30) | USB_DIR_IN)
2065
2066 static int hub_set_address(struct usb_device *udev)
2067 {
2068 int retval;
2069
2070 if (udev->devnum == 0)
2071 return -EINVAL;
2072 if (udev->state == USB_STATE_ADDRESS)
2073 return 0;
2074 if (udev->state != USB_STATE_DEFAULT)
2075 return -EINVAL;
2076 retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2077 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2078 NULL, 0, USB_CTRL_SET_TIMEOUT);
2079 if (retval == 0) {
2080 usb_set_device_state(udev, USB_STATE_ADDRESS);
2081 ep0_reinit(udev);
2082 }
2083 return retval;
2084 }
2085
2086 /* Reset device, (re)assign address, get device descriptor.
2087 * Device connection must be stable, no more debouncing needed.
2088 * Returns device in USB_STATE_ADDRESS, except on error.
2089 *
2090 * If this is called for an already-existing device (as part of
2091 * usb_reset_device), the caller must own the device lock. For a
2092 * newly detected device that is not accessible through any global
2093 * pointers, it's not necessary to lock the device.
2094 */
2095 static int
2096 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2097 int retry_counter)
2098 {
2099 static DECLARE_MUTEX(usb_address0_sem);
2100
2101 struct usb_device *hdev = hub->hdev;
2102 int i, j, retval;
2103 unsigned delay = HUB_SHORT_RESET_TIME;
2104 enum usb_device_speed oldspeed = udev->speed;
2105
2106 /* root hub ports have a slightly longer reset period
2107 * (from USB 2.0 spec, section 7.1.7.5)
2108 */
2109 if (!hdev->parent) {
2110 delay = HUB_ROOT_RESET_TIME;
2111 if (port1 == hdev->bus->otg_port)
2112 hdev->bus->b_hnp_enable = 0;
2113 }
2114
2115 /* Some low speed devices have problems with the quick delay, so */
2116 /* be a bit pessimistic with those devices. RHbug #23670 */
2117 if (oldspeed == USB_SPEED_LOW)
2118 delay = HUB_LONG_RESET_TIME;
2119
2120 down(&usb_address0_sem);
2121
2122 /* Reset the device; full speed may morph to high speed */
2123 retval = hub_port_reset(hub, port1, udev, delay);
2124 if (retval < 0) /* error or disconnect */
2125 goto fail;
2126 /* success, speed is known */
2127 retval = -ENODEV;
2128
2129 if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2130 dev_dbg(&udev->dev, "device reset changed speed!\n");
2131 goto fail;
2132 }
2133 oldspeed = udev->speed;
2134
2135 /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2136 * it's fixed size except for full speed devices.
2137 */
2138 switch (udev->speed) {
2139 case USB_SPEED_HIGH: /* fixed at 64 */
2140 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2141 break;
2142 case USB_SPEED_FULL: /* 8, 16, 32, or 64 */
2143 /* to determine the ep0 maxpacket size, try to read
2144 * the device descriptor to get bMaxPacketSize0 and
2145 * then correct our initial guess.
2146 */
2147 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2148 break;
2149 case USB_SPEED_LOW: /* fixed at 8 */
2150 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2151 break;
2152 default:
2153 goto fail;
2154 }
2155
2156 dev_info (&udev->dev,
2157 "%s %s speed USB device using %s and address %d\n",
2158 (udev->config) ? "reset" : "new",
2159 ({ char *speed; switch (udev->speed) {
2160 case USB_SPEED_LOW: speed = "low"; break;
2161 case USB_SPEED_FULL: speed = "full"; break;
2162 case USB_SPEED_HIGH: speed = "high"; break;
2163 default: speed = "?"; break;
2164 }; speed;}),
2165 udev->bus->controller->driver->name,
2166 udev->devnum);
2167
2168 /* Set up TT records, if needed */
2169 if (hdev->tt) {
2170 udev->tt = hdev->tt;
2171 udev->ttport = hdev->ttport;
2172 } else if (udev->speed != USB_SPEED_HIGH
2173 && hdev->speed == USB_SPEED_HIGH) {
2174 udev->tt = &hub->tt;
2175 udev->ttport = port1;
2176 }
2177
2178 /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2179 * Because device hardware and firmware is sometimes buggy in
2180 * this area, and this is how Linux has done it for ages.
2181 * Change it cautiously.
2182 *
2183 * NOTE: If USE_NEW_SCHEME() is true we will start by issuing
2184 * a 64-byte GET_DESCRIPTOR request. This is what Windows does,
2185 * so it may help with some non-standards-compliant devices.
2186 * Otherwise we start with SET_ADDRESS and then try to read the
2187 * first 8 bytes of the device descriptor to get the ep0 maxpacket
2188 * value.
2189 */
2190 for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2191 if (USE_NEW_SCHEME(retry_counter)) {
2192 struct usb_device_descriptor *buf;
2193 int r = 0;
2194
2195 #define GET_DESCRIPTOR_BUFSIZE 64
2196 buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2197 if (!buf) {
2198 retval = -ENOMEM;
2199 continue;
2200 }
2201
2202 /* Use a short timeout the first time through,
2203 * so that recalcitrant full-speed devices with
2204 * 8- or 16-byte ep0-maxpackets won't slow things
2205 * down tremendously by NAKing the unexpectedly
2206 * early status stage. Also, retry on all errors;
2207 * some devices are flakey.
2208 */
2209 for (j = 0; j < 3; ++j) {
2210 buf->bMaxPacketSize0 = 0;
2211 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2212 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2213 USB_DT_DEVICE << 8, 0,
2214 buf, GET_DESCRIPTOR_BUFSIZE,
2215 (i ? USB_CTRL_GET_TIMEOUT : 1000));
2216 switch (buf->bMaxPacketSize0) {
2217 case 8: case 16: case 32: case 64:
2218 if (buf->bDescriptorType ==
2219 USB_DT_DEVICE) {
2220 r = 0;
2221 break;
2222 }
2223 /* FALL THROUGH */
2224 default:
2225 if (r == 0)
2226 r = -EPROTO;
2227 break;
2228 }
2229 if (r == 0)
2230 break;
2231 }
2232 udev->descriptor.bMaxPacketSize0 =
2233 buf->bMaxPacketSize0;
2234 kfree(buf);
2235
2236 retval = hub_port_reset(hub, port1, udev, delay);
2237 if (retval < 0) /* error or disconnect */
2238 goto fail;
2239 if (oldspeed != udev->speed) {
2240 dev_dbg(&udev->dev,
2241 "device reset changed speed!\n");
2242 retval = -ENODEV;
2243 goto fail;
2244 }
2245 if (r) {
2246 dev_err(&udev->dev, "device descriptor "
2247 "read/%s, error %d\n",
2248 "64", r);
2249 retval = -EMSGSIZE;
2250 continue;
2251 }
2252 #undef GET_DESCRIPTOR_BUFSIZE
2253 }
2254
2255 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2256 retval = hub_set_address(udev);
2257 if (retval >= 0)
2258 break;
2259 msleep(200);
2260 }
2261 if (retval < 0) {
2262 dev_err(&udev->dev,
2263 "device not accepting address %d, error %d\n",
2264 udev->devnum, retval);
2265 goto fail;
2266 }
2267
2268 /* cope with hardware quirkiness:
2269 * - let SET_ADDRESS settle, some device hardware wants it
2270 * - read ep0 maxpacket even for high and low speed,
2271 */
2272 msleep(10);
2273 if (USE_NEW_SCHEME(retry_counter))
2274 break;
2275
2276 retval = usb_get_device_descriptor(udev, 8);
2277 if (retval < 8) {
2278 dev_err(&udev->dev, "device descriptor "
2279 "read/%s, error %d\n",
2280 "8", retval);
2281 if (retval >= 0)
2282 retval = -EMSGSIZE;
2283 } else {
2284 retval = 0;
2285 break;
2286 }
2287 }
2288 if (retval)
2289 goto fail;
2290
2291 i = udev->descriptor.bMaxPacketSize0;
2292 if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2293 if (udev->speed != USB_SPEED_FULL ||
2294 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2295 dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2296 retval = -EMSGSIZE;
2297 goto fail;
2298 }
2299 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2300 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2301 ep0_reinit(udev);
2302 }
2303
2304 retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2305 if (retval < (signed)sizeof(udev->descriptor)) {
2306 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2307 "all", retval);
2308 if (retval >= 0)
2309 retval = -ENOMSG;
2310 goto fail;
2311 }
2312
2313 retval = 0;
2314
2315 fail:
2316 if (retval)
2317 hub_port_disable(hub, port1, 0);
2318 up(&usb_address0_sem);
2319 return retval;
2320 }
2321
2322 static void
2323 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2324 {
2325 struct usb_qualifier_descriptor *qual;
2326 int status;
2327
2328 qual = kmalloc (sizeof *qual, SLAB_KERNEL);
2329 if (qual == NULL)
2330 return;
2331
2332 status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2333 qual, sizeof *qual);
2334 if (status == sizeof *qual) {
2335 dev_info(&udev->dev, "not running at top speed; "
2336 "connect to a high speed hub\n");
2337 /* hub LEDs are probably harder to miss than syslog */
2338 if (hub->has_indicators) {
2339 hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2340 schedule_work (&hub->leds);
2341 }
2342 }
2343 kfree(qual);
2344 }
2345
2346 static unsigned
2347 hub_power_remaining (struct usb_hub *hub)
2348 {
2349 struct usb_device *hdev = hub->hdev;
2350 int remaining;
2351 unsigned i;
2352
2353 remaining = hub->power_budget;
2354 if (!remaining) /* self-powered */
2355 return 0;
2356
2357 for (i = 0; i < hdev->maxchild; i++) {
2358 struct usb_device *udev = hdev->children[i];
2359 int delta, ceiling;
2360
2361 if (!udev)
2362 continue;
2363
2364 /* 100mA per-port ceiling, or 8mA for OTG ports */
2365 if (i != (udev->bus->otg_port - 1) || hdev->parent)
2366 ceiling = 50;
2367 else
2368 ceiling = 4;
2369
2370 if (udev->actconfig)
2371 delta = udev->actconfig->desc.bMaxPower;
2372 else
2373 delta = ceiling;
2374 // dev_dbg(&udev->dev, "budgeted %dmA\n", 2 * delta);
2375 if (delta > ceiling)
2376 dev_warn(&udev->dev, "%dmA over %dmA budget!\n",
2377 2 * (delta - ceiling), 2 * ceiling);
2378 remaining -= delta;
2379 }
2380 if (remaining < 0) {
2381 dev_warn(hub->intfdev,
2382 "%dmA over power budget!\n",
2383 -2 * remaining);
2384 remaining = 0;
2385 }
2386 return remaining;
2387 }
2388
2389 /* Handle physical or logical connection change events.
2390 * This routine is called when:
2391 * a port connection-change occurs;
2392 * a port enable-change occurs (often caused by EMI);
2393 * usb_reset_device() encounters changed descriptors (as from
2394 * a firmware download)
2395 * caller already locked the hub
2396 */
2397 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2398 u16 portstatus, u16 portchange)
2399 {
2400 struct usb_device *hdev = hub->hdev;
2401 struct device *hub_dev = hub->intfdev;
2402 int status, i;
2403
2404 dev_dbg (hub_dev,
2405 "port %d, status %04x, change %04x, %s\n",
2406 port1, portstatus, portchange, portspeed (portstatus));
2407
2408 if (hub->has_indicators) {
2409 set_port_led(hub, port1, HUB_LED_AUTO);
2410 hub->indicator[port1-1] = INDICATOR_AUTO;
2411 }
2412
2413 /* Disconnect any existing devices under this port */
2414 if (hdev->children[port1-1])
2415 usb_disconnect(&hdev->children[port1-1]);
2416 clear_bit(port1, hub->change_bits);
2417
2418 #ifdef CONFIG_USB_OTG
2419 /* during HNP, don't repeat the debounce */
2420 if (hdev->bus->is_b_host)
2421 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2422 #endif
2423
2424 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2425 status = hub_port_debounce(hub, port1);
2426 if (status < 0) {
2427 dev_err (hub_dev,
2428 "connect-debounce failed, port %d disabled\n",
2429 port1);
2430 goto done;
2431 }
2432 portstatus = status;
2433 }
2434
2435 /* Return now if nothing is connected */
2436 if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2437
2438 /* maybe switch power back on (e.g. root hub was reset) */
2439 if ((hub->descriptor->wHubCharacteristics
2440 & HUB_CHAR_LPSM) < 2
2441 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2442 set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2443
2444 if (portstatus & USB_PORT_STAT_ENABLE)
2445 goto done;
2446 return;
2447 }
2448
2449 #ifdef CONFIG_USB_SUSPEND
2450 /* If something is connected, but the port is suspended, wake it up. */
2451 if (portstatus & USB_PORT_STAT_SUSPEND) {
2452 status = hub_port_resume(hub, port1, NULL);
2453 if (status < 0) {
2454 dev_dbg(hub_dev,
2455 "can't clear suspend on port %d; %d\n",
2456 port1, status);
2457 goto done;
2458 }
2459 }
2460 #endif
2461
2462 for (i = 0; i < SET_CONFIG_TRIES; i++) {
2463 struct usb_device *udev;
2464
2465 /* reallocate for each attempt, since references
2466 * to the previous one can escape in various ways
2467 */
2468 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2469 if (!udev) {
2470 dev_err (hub_dev,
2471 "couldn't allocate port %d usb_device\n",
2472 port1);
2473 goto done;
2474 }
2475
2476 usb_set_device_state(udev, USB_STATE_POWERED);
2477 udev->speed = USB_SPEED_UNKNOWN;
2478
2479 /* set the address */
2480 choose_address(udev);
2481 if (udev->devnum <= 0) {
2482 status = -ENOTCONN; /* Don't retry */
2483 goto loop;
2484 }
2485
2486 /* reset and get descriptor */
2487 status = hub_port_init(hub, udev, port1, i);
2488 if (status < 0)
2489 goto loop;
2490
2491 /* consecutive bus-powered hubs aren't reliable; they can
2492 * violate the voltage drop budget. if the new child has
2493 * a "powered" LED, users should notice we didn't enable it
2494 * (without reading syslog), even without per-port LEDs
2495 * on the parent.
2496 */
2497 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2498 && hub->power_budget) {
2499 u16 devstat;
2500
2501 status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2502 &devstat);
2503 if (status < 0) {
2504 dev_dbg(&udev->dev, "get status %d ?\n", status);
2505 goto loop_disable;
2506 }
2507 cpu_to_le16s(&devstat);
2508 if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2509 dev_err(&udev->dev,
2510 "can't connect bus-powered hub "
2511 "to this port\n");
2512 if (hub->has_indicators) {
2513 hub->indicator[port1-1] =
2514 INDICATOR_AMBER_BLINK;
2515 schedule_work (&hub->leds);
2516 }
2517 status = -ENOTCONN; /* Don't retry */
2518 goto loop_disable;
2519 }
2520 }
2521
2522 /* check for devices running slower than they could */
2523 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2524 && udev->speed == USB_SPEED_FULL
2525 && highspeed_hubs != 0)
2526 check_highspeed (hub, udev, port1);
2527
2528 /* Store the parent's children[] pointer. At this point
2529 * udev becomes globally accessible, although presumably
2530 * no one will look at it until hdev is unlocked.
2531 */
2532 down (&udev->serialize);
2533 status = 0;
2534
2535 /* We mustn't add new devices if the parent hub has
2536 * been disconnected; we would race with the
2537 * recursively_mark_NOTATTACHED() routine.
2538 */
2539 spin_lock_irq(&device_state_lock);
2540 if (hdev->state == USB_STATE_NOTATTACHED)
2541 status = -ENOTCONN;
2542 else
2543 hdev->children[port1-1] = udev;
2544 spin_unlock_irq(&device_state_lock);
2545
2546 /* Run it through the hoops (find a driver, etc) */
2547 if (!status) {
2548 status = usb_new_device(udev);
2549 if (status) {
2550 spin_lock_irq(&device_state_lock);
2551 hdev->children[port1-1] = NULL;
2552 spin_unlock_irq(&device_state_lock);
2553 }
2554 }
2555
2556 up (&udev->serialize);
2557 if (status)
2558 goto loop_disable;
2559
2560 status = hub_power_remaining(hub);
2561 if (status)
2562 dev_dbg(hub_dev,
2563 "%dmA power budget left\n",
2564 2 * status);
2565
2566 return;
2567
2568 loop_disable:
2569 hub_port_disable(hub, port1, 1);
2570 loop:
2571 ep0_reinit(udev);
2572 release_address(udev);
2573 usb_put_dev(udev);
2574 if (status == -ENOTCONN)
2575 break;
2576 }
2577
2578 done:
2579 hub_port_disable(hub, port1, 1);
2580 }
2581
2582 static void hub_events(void)
2583 {
2584 struct list_head *tmp;
2585 struct usb_device *hdev;
2586 struct usb_interface *intf;
2587 struct usb_hub *hub;
2588 struct device *hub_dev;
2589 u16 hubstatus;
2590 u16 hubchange;
2591 u16 portstatus;
2592 u16 portchange;
2593 int i, ret;
2594 int connect_change;
2595
2596 /*
2597 * We restart the list every time to avoid a deadlock with
2598 * deleting hubs downstream from this one. This should be
2599 * safe since we delete the hub from the event list.
2600 * Not the most efficient, but avoids deadlocks.
2601 */
2602 while (1) {
2603
2604 /* Grab the first entry at the beginning of the list */
2605 spin_lock_irq(&hub_event_lock);
2606 if (list_empty(&hub_event_list)) {
2607 spin_unlock_irq(&hub_event_lock);
2608 break;
2609 }
2610
2611 tmp = hub_event_list.next;
2612 list_del_init(tmp);
2613
2614 hub = list_entry(tmp, struct usb_hub, event_list);
2615 hdev = hub->hdev;
2616 intf = to_usb_interface(hub->intfdev);
2617 hub_dev = &intf->dev;
2618
2619 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
2620 hdev->state, hub->descriptor
2621 ? hub->descriptor->bNbrPorts
2622 : 0,
2623 /* NOTE: expects max 15 ports... */
2624 (u16) hub->change_bits[0],
2625 (u16) hub->event_bits[0]);
2626
2627 usb_get_intf(intf);
2628 i = hub->resume_root_hub;
2629 spin_unlock_irq(&hub_event_lock);
2630
2631 /* Is this is a root hub wanting to be resumed? */
2632 if (i)
2633 usb_resume_device(hdev);
2634
2635 /* Lock the device, then check to see if we were
2636 * disconnected while waiting for the lock to succeed. */
2637 if (locktree(hdev) < 0) {
2638 usb_put_intf(intf);
2639 continue;
2640 }
2641 if (hub != usb_get_intfdata(intf))
2642 goto loop;
2643
2644 /* If the hub has died, clean up after it */
2645 if (hdev->state == USB_STATE_NOTATTACHED) {
2646 hub_pre_reset(hub);
2647 goto loop;
2648 }
2649
2650 /* If this is an inactive or suspended hub, do nothing */
2651 if (hub->quiescing)
2652 goto loop;
2653
2654 if (hub->error) {
2655 dev_dbg (hub_dev, "resetting for error %d\n",
2656 hub->error);
2657
2658 ret = usb_reset_device(hdev);
2659 if (ret) {
2660 dev_dbg (hub_dev,
2661 "error resetting hub: %d\n", ret);
2662 goto loop;
2663 }
2664
2665 hub->nerrors = 0;
2666 hub->error = 0;
2667 }
2668
2669 /* deal with port status changes */
2670 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2671 if (test_bit(i, hub->busy_bits))
2672 continue;
2673 connect_change = test_bit(i, hub->change_bits);
2674 if (!test_and_clear_bit(i, hub->event_bits) &&
2675 !connect_change && !hub->activating)
2676 continue;
2677
2678 ret = hub_port_status(hub, i,
2679 &portstatus, &portchange);
2680 if (ret < 0)
2681 continue;
2682
2683 if (hub->activating && !hdev->children[i-1] &&
2684 (portstatus &
2685 USB_PORT_STAT_CONNECTION))
2686 connect_change = 1;
2687
2688 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2689 clear_port_feature(hdev, i,
2690 USB_PORT_FEAT_C_CONNECTION);
2691 connect_change = 1;
2692 }
2693
2694 if (portchange & USB_PORT_STAT_C_ENABLE) {
2695 if (!connect_change)
2696 dev_dbg (hub_dev,
2697 "port %d enable change, "
2698 "status %08x\n",
2699 i, portstatus);
2700 clear_port_feature(hdev, i,
2701 USB_PORT_FEAT_C_ENABLE);
2702
2703 /*
2704 * EM interference sometimes causes badly
2705 * shielded USB devices to be shutdown by
2706 * the hub, this hack enables them again.
2707 * Works at least with mouse driver.
2708 */
2709 if (!(portstatus & USB_PORT_STAT_ENABLE)
2710 && !connect_change
2711 && hdev->children[i-1]) {
2712 dev_err (hub_dev,
2713 "port %i "
2714 "disabled by hub (EMI?), "
2715 "re-enabling...\n",
2716 i);
2717 connect_change = 1;
2718 }
2719 }
2720
2721 if (portchange & USB_PORT_STAT_C_SUSPEND) {
2722 clear_port_feature(hdev, i,
2723 USB_PORT_FEAT_C_SUSPEND);
2724 if (hdev->children[i-1]) {
2725 ret = remote_wakeup(hdev->
2726 children[i-1]);
2727 if (ret < 0)
2728 connect_change = 1;
2729 } else {
2730 ret = -ENODEV;
2731 hub_port_disable(hub, i, 1);
2732 }
2733 dev_dbg (hub_dev,
2734 "resume on port %d, status %d\n",
2735 i, ret);
2736 }
2737
2738 if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2739 dev_err (hub_dev,
2740 "over-current change on port %d\n",
2741 i);
2742 clear_port_feature(hdev, i,
2743 USB_PORT_FEAT_C_OVER_CURRENT);
2744 hub_power_on(hub);
2745 }
2746
2747 if (portchange & USB_PORT_STAT_C_RESET) {
2748 dev_dbg (hub_dev,
2749 "reset change on port %d\n",
2750 i);
2751 clear_port_feature(hdev, i,
2752 USB_PORT_FEAT_C_RESET);
2753 }
2754
2755 if (connect_change)
2756 hub_port_connect_change(hub, i,
2757 portstatus, portchange);
2758 } /* end for i */
2759
2760 /* deal with hub status changes */
2761 if (test_and_clear_bit(0, hub->event_bits) == 0)
2762 ; /* do nothing */
2763 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2764 dev_err (hub_dev, "get_hub_status failed\n");
2765 else {
2766 if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2767 dev_dbg (hub_dev, "power change\n");
2768 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2769 }
2770 if (hubchange & HUB_CHANGE_OVERCURRENT) {
2771 dev_dbg (hub_dev, "overcurrent change\n");
2772 msleep(500); /* Cool down */
2773 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2774 hub_power_on(hub);
2775 }
2776 }
2777
2778 hub->activating = 0;
2779
2780 /* If this is a root hub, tell the HCD it's okay to
2781 * re-enable port-change interrupts now. */
2782 if (!hdev->parent)
2783 usb_enable_root_hub_irq(hdev->bus);
2784
2785 loop:
2786 usb_unlock_device(hdev);
2787 usb_put_intf(intf);
2788
2789 } /* end while (1) */
2790 }
2791
2792 static int hub_thread(void *__unused)
2793 {
2794 do {
2795 hub_events();
2796 wait_event_interruptible(khubd_wait,
2797 !list_empty(&hub_event_list) ||
2798 kthread_should_stop());
2799 try_to_freeze();
2800 } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2801
2802 pr_debug("%s: khubd exiting\n", usbcore_name);
2803 return 0;
2804 }
2805
2806 static struct usb_device_id hub_id_table [] = {
2807 { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2808 .bDeviceClass = USB_CLASS_HUB},
2809 { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2810 .bInterfaceClass = USB_CLASS_HUB},
2811 { } /* Terminating entry */
2812 };
2813
2814 MODULE_DEVICE_TABLE (usb, hub_id_table);
2815
2816 static struct usb_driver hub_driver = {
2817 .owner = THIS_MODULE,
2818 .name = "hub",
2819 .probe = hub_probe,
2820 .disconnect = hub_disconnect,
2821 .suspend = hub_suspend,
2822 .resume = hub_resume,
2823 .ioctl = hub_ioctl,
2824 .id_table = hub_id_table,
2825 };
2826
2827 int usb_hub_init(void)
2828 {
2829 if (usb_register(&hub_driver) < 0) {
2830 printk(KERN_ERR "%s: can't register hub driver\n",
2831 usbcore_name);
2832 return -1;
2833 }
2834
2835 khubd_task = kthread_run(hub_thread, NULL, "khubd");
2836 if (!IS_ERR(khubd_task))
2837 return 0;
2838
2839 /* Fall through if kernel_thread failed */
2840 usb_deregister(&hub_driver);
2841 printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2842
2843 return -1;
2844 }
2845
2846 void usb_hub_cleanup(void)
2847 {
2848 kthread_stop(khubd_task);
2849
2850 /*
2851 * Hub resources are freed for us by usb_deregister. It calls
2852 * usb_driver_purge on every device which in turn calls that
2853 * devices disconnect function if it is using this driver.
2854 * The hub_disconnect function takes care of releasing the
2855 * individual hub resources. -greg
2856 */
2857 usb_deregister(&hub_driver);
2858 } /* usb_hub_cleanup() */
2859
2860 static int config_descriptors_changed(struct usb_device *udev)
2861 {
2862 unsigned index;
2863 unsigned len = 0;
2864 struct usb_config_descriptor *buf;
2865
2866 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2867 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2868 len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2869 }
2870 buf = kmalloc (len, SLAB_KERNEL);
2871 if (buf == NULL) {
2872 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2873 /* assume the worst */
2874 return 1;
2875 }
2876 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2877 int length;
2878 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2879
2880 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2881 old_length);
2882 if (length < old_length) {
2883 dev_dbg(&udev->dev, "config index %d, error %d\n",
2884 index, length);
2885 break;
2886 }
2887 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2888 != 0) {
2889 dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2890 index, buf->bConfigurationValue);
2891 break;
2892 }
2893 }
2894 kfree(buf);
2895 return index != udev->descriptor.bNumConfigurations;
2896 }
2897
2898 /**
2899 * usb_reset_device - perform a USB port reset to reinitialize a device
2900 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2901 *
2902 * WARNING - don't reset any device unless drivers for all of its
2903 * interfaces are expecting that reset! Maybe some driver->reset()
2904 * method should eventually help ensure sufficient cooperation.
2905 *
2906 * Do a port reset, reassign the device's address, and establish its
2907 * former operating configuration. If the reset fails, or the device's
2908 * descriptors change from their values before the reset, or the original
2909 * configuration and altsettings cannot be restored, a flag will be set
2910 * telling khubd to pretend the device has been disconnected and then
2911 * re-connected. All drivers will be unbound, and the device will be
2912 * re-enumerated and probed all over again.
2913 *
2914 * Returns 0 if the reset succeeded, -ENODEV if the device has been
2915 * flagged for logical disconnection, or some other negative error code
2916 * if the reset wasn't even attempted.
2917 *
2918 * The caller must own the device lock. For example, it's safe to use
2919 * this from a driver probe() routine after downloading new firmware.
2920 * For calls that might not occur during probe(), drivers should lock
2921 * the device using usb_lock_device_for_reset().
2922 */
2923 int usb_reset_device(struct usb_device *udev)
2924 {
2925 struct usb_device *parent_hdev = udev->parent;
2926 struct usb_hub *parent_hub;
2927 struct usb_device_descriptor descriptor = udev->descriptor;
2928 struct usb_hub *hub = NULL;
2929 int i, ret = 0, port1 = -1;
2930
2931 if (udev->state == USB_STATE_NOTATTACHED ||
2932 udev->state == USB_STATE_SUSPENDED) {
2933 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2934 udev->state);
2935 return -EINVAL;
2936 }
2937
2938 if (!parent_hdev) {
2939 /* this requires hcd-specific logic; see OHCI hc_restart() */
2940 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2941 return -EISDIR;
2942 }
2943
2944 for (i = 0; i < parent_hdev->maxchild; i++)
2945 if (parent_hdev->children[i] == udev) {
2946 port1 = i + 1;
2947 break;
2948 }
2949
2950 if (port1 < 0) {
2951 /* If this ever happens, it's very bad */
2952 dev_err(&udev->dev, "Can't locate device's port!\n");
2953 return -ENOENT;
2954 }
2955 parent_hub = hdev_to_hub(parent_hdev);
2956
2957 /* If we're resetting an active hub, take some special actions */
2958 if (udev->actconfig &&
2959 udev->actconfig->interface[0]->dev.driver ==
2960 &hub_driver.driver &&
2961 (hub = hdev_to_hub(udev)) != NULL) {
2962 hub_pre_reset(hub);
2963 }
2964
2965 set_bit(port1, parent_hub->busy_bits);
2966 for (i = 0; i < SET_CONFIG_TRIES; ++i) {
2967
2968 /* ep0 maxpacket size may change; let the HCD know about it.
2969 * Other endpoints will be handled by re-enumeration. */
2970 ep0_reinit(udev);
2971 ret = hub_port_init(parent_hub, udev, port1, i);
2972 if (ret >= 0)
2973 break;
2974 }
2975 clear_bit(port1, parent_hub->busy_bits);
2976 if (ret < 0)
2977 goto re_enumerate;
2978
2979 /* Device might have changed firmware (DFU or similar) */
2980 if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
2981 || config_descriptors_changed (udev)) {
2982 dev_info(&udev->dev, "device firmware changed\n");
2983 udev->descriptor = descriptor; /* for disconnect() calls */
2984 goto re_enumerate;
2985 }
2986
2987 if (!udev->actconfig)
2988 goto done;
2989
2990 ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2991 USB_REQ_SET_CONFIGURATION, 0,
2992 udev->actconfig->desc.bConfigurationValue, 0,
2993 NULL, 0, USB_CTRL_SET_TIMEOUT);
2994 if (ret < 0) {
2995 dev_err(&udev->dev,
2996 "can't restore configuration #%d (error=%d)\n",
2997 udev->actconfig->desc.bConfigurationValue, ret);
2998 goto re_enumerate;
2999 }
3000 usb_set_device_state(udev, USB_STATE_CONFIGURED);
3001
3002 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3003 struct usb_interface *intf = udev->actconfig->interface[i];
3004 struct usb_interface_descriptor *desc;
3005
3006 /* set_interface resets host side toggle even
3007 * for altsetting zero. the interface may have no driver.
3008 */
3009 desc = &intf->cur_altsetting->desc;
3010 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3011 desc->bAlternateSetting);
3012 if (ret < 0) {
3013 dev_err(&udev->dev, "failed to restore interface %d "
3014 "altsetting %d (error=%d)\n",
3015 desc->bInterfaceNumber,
3016 desc->bAlternateSetting,
3017 ret);
3018 goto re_enumerate;
3019 }
3020 }
3021
3022 done:
3023 if (hub)
3024 hub_post_reset(hub);
3025 return 0;
3026
3027 re_enumerate:
3028 hub_port_logical_disconnect(parent_hub, port1);
3029 return -ENODEV;
3030 }
x86 "subsystem" repository