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USB: add reset_resume method
[wandboard.git] / drivers / usb / core / hub.c
blob0b8ed414d5cf793b3912e09af6b75c75c37991cc
1 /*
2 * USB hub driver.
3 *
4 * (C) Copyright 1999 Linus Torvalds
5 * (C) Copyright 1999 Johannes Erdfelt
6 * (C) Copyright 1999 Gregory P. Smith
7 * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
8 *
9 */
10
11 #include <linux/kernel.h>
12 #include <linux/errno.h>
13 #include <linux/module.h>
14 #include <linux/moduleparam.h>
15 #include <linux/completion.h>
16 #include <linux/sched.h>
17 #include <linux/list.h>
18 #include <linux/slab.h>
19 #include <linux/ioctl.h>
20 #include <linux/usb.h>
21 #include <linux/usbdevice_fs.h>
22 #include <linux/kthread.h>
23 #include <linux/mutex.h>
24 #include <linux/freezer.h>
25
26 #include <asm/semaphore.h>
27 #include <asm/uaccess.h>
28 #include <asm/byteorder.h>
29
30 #include "usb.h"
31 #include "hcd.h"
32 #include "hub.h"
33
34 struct usb_hub {
35 struct device *intfdev; /* the "interface" device */
36 struct usb_device *hdev;
37 struct kref kref;
38 struct urb *urb; /* for interrupt polling pipe */
39
40 /* buffer for urb ... with extra space in case of babble */
41 char (*buffer)[8];
42 dma_addr_t buffer_dma; /* DMA address for buffer */
43 union {
44 struct usb_hub_status hub;
45 struct usb_port_status port;
46 } *status; /* buffer for status reports */
47 struct mutex status_mutex; /* for the status buffer */
48
49 int error; /* last reported error */
50 int nerrors; /* track consecutive errors */
51
52 struct list_head event_list; /* hubs w/data or errs ready */
53 unsigned long event_bits[1]; /* status change bitmask */
54 unsigned long change_bits[1]; /* ports with logical connect
55 status change */
56 unsigned long busy_bits[1]; /* ports being reset or
57 resumed */
58 #if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
59 #error event_bits[] is too short!
60 #endif
61
62 struct usb_hub_descriptor *descriptor; /* class descriptor */
63 struct usb_tt tt; /* Transaction Translator */
64
65 unsigned mA_per_port; /* current for each child */
66
67 unsigned limited_power:1;
68 unsigned quiescing:1;
69 unsigned activating:1;
70 unsigned disconnected:1;
71
72 unsigned has_indicators:1;
73 u8 indicator[USB_MAXCHILDREN];
74 struct delayed_work leds;
75 };
76
77
78 /* Protect struct usb_device->state and ->children members
79 * Note: Both are also protected by ->dev.sem, except that ->state can
80 * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
81 static DEFINE_SPINLOCK(device_state_lock);
82
83 /* khubd's worklist and its lock */
84 static DEFINE_SPINLOCK(hub_event_lock);
85 static LIST_HEAD(hub_event_list); /* List of hubs needing servicing */
86
87 /* Wakes up khubd */
88 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
89
90 static struct task_struct *khubd_task;
91
92 /* cycle leds on hubs that aren't blinking for attention */
93 static int blinkenlights = 0;
94 module_param (blinkenlights, bool, S_IRUGO);
95 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
96
97 /*
98 * As of 2.6.10 we introduce a new USB device initialization scheme which
99 * closely resembles the way Windows works. Hopefully it will be compatible
100 * with a wider range of devices than the old scheme. However some previously
101 * working devices may start giving rise to "device not accepting address"
102 * errors; if that happens the user can try the old scheme by adjusting the
103 * following module parameters.
104 *
105 * For maximum flexibility there are two boolean parameters to control the
106 * hub driver's behavior. On the first initialization attempt, if the
107 * "old_scheme_first" parameter is set then the old scheme will be used,
108 * otherwise the new scheme is used. If that fails and "use_both_schemes"
109 * is set, then the driver will make another attempt, using the other scheme.
110 */
111 static int old_scheme_first = 0;
112 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
113 MODULE_PARM_DESC(old_scheme_first,
114 "start with the old device initialization scheme");
115
116 static int use_both_schemes = 1;
117 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
118 MODULE_PARM_DESC(use_both_schemes,
119 "try the other device initialization scheme if the "
120 "first one fails");
121
122
123 static inline char *portspeed(int portstatus)
124 {
125 if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
126 return "480 Mb/s";
127 else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
128 return "1.5 Mb/s";
129 else
130 return "12 Mb/s";
131 }
132
133 /* Note that hdev or one of its children must be locked! */
134 static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
135 {
136 return usb_get_intfdata(hdev->actconfig->interface[0]);
137 }
138
139 /* USB 2.0 spec Section 11.24.4.5 */
140 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
141 {
142 int i, ret;
143
144 for (i = 0; i < 3; i++) {
145 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
146 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
147 USB_DT_HUB << 8, 0, data, size,
148 USB_CTRL_GET_TIMEOUT);
149 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
150 return ret;
151 }
152 return -EINVAL;
153 }
154
155 /*
156 * USB 2.0 spec Section 11.24.2.1
157 */
158 static int clear_hub_feature(struct usb_device *hdev, int feature)
159 {
160 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
161 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
162 }
163
164 /*
165 * USB 2.0 spec Section 11.24.2.2
166 */
167 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
168 {
169 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
170 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
171 NULL, 0, 1000);
172 }
173
174 /*
175 * USB 2.0 spec Section 11.24.2.13
176 */
177 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
178 {
179 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
180 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
181 NULL, 0, 1000);
182 }
183
184 /*
185 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
186 * for info about using port indicators
187 */
188 static void set_port_led(
189 struct usb_hub *hub,
190 int port1,
191 int selector
192 )
193 {
194 int status = set_port_feature(hub->hdev, (selector << 8) | port1,
195 USB_PORT_FEAT_INDICATOR);
196 if (status < 0)
197 dev_dbg (hub->intfdev,
198 "port %d indicator %s status %d\n",
199 port1,
200 ({ char *s; switch (selector) {
201 case HUB_LED_AMBER: s = "amber"; break;
202 case HUB_LED_GREEN: s = "green"; break;
203 case HUB_LED_OFF: s = "off"; break;
204 case HUB_LED_AUTO: s = "auto"; break;
205 default: s = "??"; break;
206 }; s; }),
207 status);
208 }
209
210 #define LED_CYCLE_PERIOD ((2*HZ)/3)
211
212 static void led_work (struct work_struct *work)
213 {
214 struct usb_hub *hub =
215 container_of(work, struct usb_hub, leds.work);
216 struct usb_device *hdev = hub->hdev;
217 unsigned i;
218 unsigned changed = 0;
219 int cursor = -1;
220
221 if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
222 return;
223
224 for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
225 unsigned selector, mode;
226
227 /* 30%-50% duty cycle */
228
229 switch (hub->indicator[i]) {
230 /* cycle marker */
231 case INDICATOR_CYCLE:
232 cursor = i;
233 selector = HUB_LED_AUTO;
234 mode = INDICATOR_AUTO;
235 break;
236 /* blinking green = sw attention */
237 case INDICATOR_GREEN_BLINK:
238 selector = HUB_LED_GREEN;
239 mode = INDICATOR_GREEN_BLINK_OFF;
240 break;
241 case INDICATOR_GREEN_BLINK_OFF:
242 selector = HUB_LED_OFF;
243 mode = INDICATOR_GREEN_BLINK;
244 break;
245 /* blinking amber = hw attention */
246 case INDICATOR_AMBER_BLINK:
247 selector = HUB_LED_AMBER;
248 mode = INDICATOR_AMBER_BLINK_OFF;
249 break;
250 case INDICATOR_AMBER_BLINK_OFF:
251 selector = HUB_LED_OFF;
252 mode = INDICATOR_AMBER_BLINK;
253 break;
254 /* blink green/amber = reserved */
255 case INDICATOR_ALT_BLINK:
256 selector = HUB_LED_GREEN;
257 mode = INDICATOR_ALT_BLINK_OFF;
258 break;
259 case INDICATOR_ALT_BLINK_OFF:
260 selector = HUB_LED_AMBER;
261 mode = INDICATOR_ALT_BLINK;
262 break;
263 default:
264 continue;
265 }
266 if (selector != HUB_LED_AUTO)
267 changed = 1;
268 set_port_led(hub, i + 1, selector);
269 hub->indicator[i] = mode;
270 }
271 if (!changed && blinkenlights) {
272 cursor++;
273 cursor %= hub->descriptor->bNbrPorts;
274 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
275 hub->indicator[cursor] = INDICATOR_CYCLE;
276 changed++;
277 }
278 if (changed)
279 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
280 }
281
282 /* use a short timeout for hub/port status fetches */
283 #define USB_STS_TIMEOUT 1000
284 #define USB_STS_RETRIES 5
285
286 /*
287 * USB 2.0 spec Section 11.24.2.6
288 */
289 static int get_hub_status(struct usb_device *hdev,
290 struct usb_hub_status *data)
291 {
292 int i, status = -ETIMEDOUT;
293
294 for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
295 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
296 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
297 data, sizeof(*data), USB_STS_TIMEOUT);
298 }
299 return status;
300 }
301
302 /*
303 * USB 2.0 spec Section 11.24.2.7
304 */
305 static int get_port_status(struct usb_device *hdev, int port1,
306 struct usb_port_status *data)
307 {
308 int i, status = -ETIMEDOUT;
309
310 for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
311 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
312 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
313 data, sizeof(*data), USB_STS_TIMEOUT);
314 }
315 return status;
316 }
317
318 static void kick_khubd(struct usb_hub *hub)
319 {
320 unsigned long flags;
321
322 /* Suppress autosuspend until khubd runs */
323 to_usb_interface(hub->intfdev)->pm_usage_cnt = 1;
324
325 spin_lock_irqsave(&hub_event_lock, flags);
326 if (!hub->disconnected & list_empty(&hub->event_list)) {
327 list_add_tail(&hub->event_list, &hub_event_list);
328 wake_up(&khubd_wait);
329 }
330 spin_unlock_irqrestore(&hub_event_lock, flags);
331 }
332
333 void usb_kick_khubd(struct usb_device *hdev)
334 {
335 /* FIXME: What if hdev isn't bound to the hub driver? */
336 kick_khubd(hdev_to_hub(hdev));
337 }
338
339
340 /* completion function, fires on port status changes and various faults */
341 static void hub_irq(struct urb *urb)
342 {
343 struct usb_hub *hub = urb->context;
344 int status;
345 int i;
346 unsigned long bits;
347
348 switch (urb->status) {
349 case -ENOENT: /* synchronous unlink */
350 case -ECONNRESET: /* async unlink */
351 case -ESHUTDOWN: /* hardware going away */
352 return;
353
354 default: /* presumably an error */
355 /* Cause a hub reset after 10 consecutive errors */
356 dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
357 if ((++hub->nerrors < 10) || hub->error)
358 goto resubmit;
359 hub->error = urb->status;
360 /* FALL THROUGH */
361
362 /* let khubd handle things */
363 case 0: /* we got data: port status changed */
364 bits = 0;
365 for (i = 0; i < urb->actual_length; ++i)
366 bits |= ((unsigned long) ((*hub->buffer)[i]))
367 << (i*8);
368 hub->event_bits[0] = bits;
369 break;
370 }
371
372 hub->nerrors = 0;
373
374 /* Something happened, let khubd figure it out */
375 kick_khubd(hub);
376
377 resubmit:
378 if (hub->quiescing)
379 return;
380
381 if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
382 && status != -ENODEV && status != -EPERM)
383 dev_err (hub->intfdev, "resubmit --> %d\n", status);
384 }
385
386 /* USB 2.0 spec Section 11.24.2.3 */
387 static inline int
388 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
389 {
390 return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
391 HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
392 tt, NULL, 0, 1000);
393 }
394
395 /*
396 * enumeration blocks khubd for a long time. we use keventd instead, since
397 * long blocking there is the exception, not the rule. accordingly, HCDs
398 * talking to TTs must queue control transfers (not just bulk and iso), so
399 * both can talk to the same hub concurrently.
400 */
401 static void hub_tt_kevent (struct work_struct *work)
402 {
403 struct usb_hub *hub =
404 container_of(work, struct usb_hub, tt.kevent);
405 unsigned long flags;
406 int limit = 100;
407
408 spin_lock_irqsave (&hub->tt.lock, flags);
409 while (--limit && !list_empty (&hub->tt.clear_list)) {
410 struct list_head *temp;
411 struct usb_tt_clear *clear;
412 struct usb_device *hdev = hub->hdev;
413 int status;
414
415 temp = hub->tt.clear_list.next;
416 clear = list_entry (temp, struct usb_tt_clear, clear_list);
417 list_del (&clear->clear_list);
418
419 /* drop lock so HCD can concurrently report other TT errors */
420 spin_unlock_irqrestore (&hub->tt.lock, flags);
421 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
422 spin_lock_irqsave (&hub->tt.lock, flags);
423
424 if (status)
425 dev_err (&hdev->dev,
426 "clear tt %d (%04x) error %d\n",
427 clear->tt, clear->devinfo, status);
428 kfree(clear);
429 }
430 spin_unlock_irqrestore (&hub->tt.lock, flags);
431 }
432
433 /**
434 * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
435 * @udev: the device whose split transaction failed
436 * @pipe: identifies the endpoint of the failed transaction
437 *
438 * High speed HCDs use this to tell the hub driver that some split control or
439 * bulk transaction failed in a way that requires clearing internal state of
440 * a transaction translator. This is normally detected (and reported) from
441 * interrupt context.
442 *
443 * It may not be possible for that hub to handle additional full (or low)
444 * speed transactions until that state is fully cleared out.
445 */
446 void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
447 {
448 struct usb_tt *tt = udev->tt;
449 unsigned long flags;
450 struct usb_tt_clear *clear;
451
452 /* we've got to cope with an arbitrary number of pending TT clears,
453 * since each TT has "at least two" buffers that can need it (and
454 * there can be many TTs per hub). even if they're uncommon.
455 */
456 if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) {
457 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
458 /* FIXME recover somehow ... RESET_TT? */
459 return;
460 }
461
462 /* info that CLEAR_TT_BUFFER needs */
463 clear->tt = tt->multi ? udev->ttport : 1;
464 clear->devinfo = usb_pipeendpoint (pipe);
465 clear->devinfo |= udev->devnum << 4;
466 clear->devinfo |= usb_pipecontrol (pipe)
467 ? (USB_ENDPOINT_XFER_CONTROL << 11)
468 : (USB_ENDPOINT_XFER_BULK << 11);
469 if (usb_pipein (pipe))
470 clear->devinfo |= 1 << 15;
471
472 /* tell keventd to clear state for this TT */
473 spin_lock_irqsave (&tt->lock, flags);
474 list_add_tail (&clear->clear_list, &tt->clear_list);
475 schedule_work (&tt->kevent);
476 spin_unlock_irqrestore (&tt->lock, flags);
477 }
478
479 static void hub_power_on(struct usb_hub *hub)
480 {
481 int port1;
482 unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
483 u16 wHubCharacteristics =
484 le16_to_cpu(hub->descriptor->wHubCharacteristics);
485
486 /* Enable power on each port. Some hubs have reserved values
487 * of LPSM (> 2) in their descriptors, even though they are
488 * USB 2.0 hubs. Some hubs do not implement port-power switching
489 * but only emulate it. In all cases, the ports won't work
490 * unless we send these messages to the hub.
491 */
492 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
493 dev_dbg(hub->intfdev, "enabling power on all ports\n");
494 else
495 dev_dbg(hub->intfdev, "trying to enable port power on "
496 "non-switchable hub\n");
497 for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
498 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
499
500 /* Wait at least 100 msec for power to become stable */
501 msleep(max(pgood_delay, (unsigned) 100));
502 }
503
504 static void hub_quiesce(struct usb_hub *hub)
505 {
506 /* (nonblocking) khubd and related activity won't re-trigger */
507 hub->quiescing = 1;
508 hub->activating = 0;
509
510 /* (blocking) stop khubd and related activity */
511 usb_kill_urb(hub->urb);
512 if (hub->has_indicators)
513 cancel_delayed_work(&hub->leds);
514 if (hub->has_indicators || hub->tt.hub)
515 flush_scheduled_work();
516 }
517
518 static void hub_activate(struct usb_hub *hub)
519 {
520 int status;
521
522 hub->quiescing = 0;
523 hub->activating = 1;
524
525 status = usb_submit_urb(hub->urb, GFP_NOIO);
526 if (status < 0)
527 dev_err(hub->intfdev, "activate --> %d\n", status);
528 if (hub->has_indicators && blinkenlights)
529 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
530
531 /* scan all ports ASAP */
532 kick_khubd(hub);
533 }
534
535 static int hub_hub_status(struct usb_hub *hub,
536 u16 *status, u16 *change)
537 {
538 int ret;
539
540 mutex_lock(&hub->status_mutex);
541 ret = get_hub_status(hub->hdev, &hub->status->hub);
542 if (ret < 0)
543 dev_err (hub->intfdev,
544 "%s failed (err = %d)\n", __FUNCTION__, ret);
545 else {
546 *status = le16_to_cpu(hub->status->hub.wHubStatus);
547 *change = le16_to_cpu(hub->status->hub.wHubChange);
548 ret = 0;
549 }
550 mutex_unlock(&hub->status_mutex);
551 return ret;
552 }
553
554 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
555 {
556 struct usb_device *hdev = hub->hdev;
557 int ret = 0;
558
559 if (hdev->children[port1-1] && set_state)
560 usb_set_device_state(hdev->children[port1-1],
561 USB_STATE_NOTATTACHED);
562 if (!hub->error)
563 ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
564 if (ret)
565 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
566 port1, ret);
567 return ret;
568 }
569
570 /*
571 * Disable a port and mark a logical connnect-change event, so that some
572 * time later khubd will disconnect() any existing usb_device on the port
573 * and will re-enumerate if there actually is a device attached.
574 */
575 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
576 {
577 dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
578 hub_port_disable(hub, port1, 1);
579
580 /* FIXME let caller ask to power down the port:
581 * - some devices won't enumerate without a VBUS power cycle
582 * - SRP saves power that way
583 * - ... new call, TBD ...
584 * That's easy if this hub can switch power per-port, and
585 * khubd reactivates the port later (timer, SRP, etc).
586 * Powerdown must be optional, because of reset/DFU.
587 */
588
589 set_bit(port1, hub->change_bits);
590 kick_khubd(hub);
591 }
592
593 static void disconnect_all_children(struct usb_hub *hub, int logical)
594 {
595 struct usb_device *hdev = hub->hdev;
596 int port1;
597
598 for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
599 if (hdev->children[port1-1]) {
600 if (logical)
601 hub_port_logical_disconnect(hub, port1);
602 else
603 usb_disconnect(&hdev->children[port1-1]);
604 }
605 }
606 }
607
608 /* caller has locked the hub device */
609 static int hub_pre_reset(struct usb_interface *intf)
610 {
611 struct usb_hub *hub = usb_get_intfdata(intf);
612
613 disconnect_all_children(hub, 0);
614 hub_quiesce(hub);
615 return 0;
616 }
617
618 /* caller has locked the hub device */
619 static int hub_post_reset(struct usb_interface *intf)
620 {
621 struct usb_hub *hub = usb_get_intfdata(intf);
622
623 hub_power_on(hub);
624 hub_activate(hub);
625 return 0;
626 }
627
628 static int hub_configure(struct usb_hub *hub,
629 struct usb_endpoint_descriptor *endpoint)
630 {
631 struct usb_device *hdev = hub->hdev;
632 struct device *hub_dev = hub->intfdev;
633 u16 hubstatus, hubchange;
634 u16 wHubCharacteristics;
635 unsigned int pipe;
636 int maxp, ret;
637 char *message;
638
639 hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
640 &hub->buffer_dma);
641 if (!hub->buffer) {
642 message = "can't allocate hub irq buffer";
643 ret = -ENOMEM;
644 goto fail;
645 }
646
647 hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
648 if (!hub->status) {
649 message = "can't kmalloc hub status buffer";
650 ret = -ENOMEM;
651 goto fail;
652 }
653 mutex_init(&hub->status_mutex);
654
655 hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
656 if (!hub->descriptor) {
657 message = "can't kmalloc hub descriptor";
658 ret = -ENOMEM;
659 goto fail;
660 }
661
662 /* Request the entire hub descriptor.
663 * hub->descriptor can handle USB_MAXCHILDREN ports,
664 * but the hub can/will return fewer bytes here.
665 */
666 ret = get_hub_descriptor(hdev, hub->descriptor,
667 sizeof(*hub->descriptor));
668 if (ret < 0) {
669 message = "can't read hub descriptor";
670 goto fail;
671 } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
672 message = "hub has too many ports!";
673 ret = -ENODEV;
674 goto fail;
675 }
676
677 hdev->maxchild = hub->descriptor->bNbrPorts;
678 dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
679 (hdev->maxchild == 1) ? "" : "s");
680
681 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
682
683 if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
684 int i;
685 char portstr [USB_MAXCHILDREN + 1];
686
687 for (i = 0; i < hdev->maxchild; i++)
688 portstr[i] = hub->descriptor->DeviceRemovable
689 [((i + 1) / 8)] & (1 << ((i + 1) % 8))
690 ? 'F' : 'R';
691 portstr[hdev->maxchild] = 0;
692 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
693 } else
694 dev_dbg(hub_dev, "standalone hub\n");
695
696 switch (wHubCharacteristics & HUB_CHAR_LPSM) {
697 case 0x00:
698 dev_dbg(hub_dev, "ganged power switching\n");
699 break;
700 case 0x01:
701 dev_dbg(hub_dev, "individual port power switching\n");
702 break;
703 case 0x02:
704 case 0x03:
705 dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
706 break;
707 }
708
709 switch (wHubCharacteristics & HUB_CHAR_OCPM) {
710 case 0x00:
711 dev_dbg(hub_dev, "global over-current protection\n");
712 break;
713 case 0x08:
714 dev_dbg(hub_dev, "individual port over-current protection\n");
715 break;
716 case 0x10:
717 case 0x18:
718 dev_dbg(hub_dev, "no over-current protection\n");
719 break;
720 }
721
722 spin_lock_init (&hub->tt.lock);
723 INIT_LIST_HEAD (&hub->tt.clear_list);
724 INIT_WORK (&hub->tt.kevent, hub_tt_kevent);
725 switch (hdev->descriptor.bDeviceProtocol) {
726 case 0:
727 break;
728 case 1:
729 dev_dbg(hub_dev, "Single TT\n");
730 hub->tt.hub = hdev;
731 break;
732 case 2:
733 ret = usb_set_interface(hdev, 0, 1);
734 if (ret == 0) {
735 dev_dbg(hub_dev, "TT per port\n");
736 hub->tt.multi = 1;
737 } else
738 dev_err(hub_dev, "Using single TT (err %d)\n",
739 ret);
740 hub->tt.hub = hdev;
741 break;
742 default:
743 dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
744 hdev->descriptor.bDeviceProtocol);
745 break;
746 }
747
748 /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
749 switch (wHubCharacteristics & HUB_CHAR_TTTT) {
750 case HUB_TTTT_8_BITS:
751 if (hdev->descriptor.bDeviceProtocol != 0) {
752 hub->tt.think_time = 666;
753 dev_dbg(hub_dev, "TT requires at most %d "
754 "FS bit times (%d ns)\n",
755 8, hub->tt.think_time);
756 }
757 break;
758 case HUB_TTTT_16_BITS:
759 hub->tt.think_time = 666 * 2;
760 dev_dbg(hub_dev, "TT requires at most %d "
761 "FS bit times (%d ns)\n",
762 16, hub->tt.think_time);
763 break;
764 case HUB_TTTT_24_BITS:
765 hub->tt.think_time = 666 * 3;
766 dev_dbg(hub_dev, "TT requires at most %d "
767 "FS bit times (%d ns)\n",
768 24, hub->tt.think_time);
769 break;
770 case HUB_TTTT_32_BITS:
771 hub->tt.think_time = 666 * 4;
772 dev_dbg(hub_dev, "TT requires at most %d "
773 "FS bit times (%d ns)\n",
774 32, hub->tt.think_time);
775 break;
776 }
777
778 /* probe() zeroes hub->indicator[] */
779 if (wHubCharacteristics & HUB_CHAR_PORTIND) {
780 hub->has_indicators = 1;
781 dev_dbg(hub_dev, "Port indicators are supported\n");
782 }
783
784 dev_dbg(hub_dev, "power on to power good time: %dms\n",
785 hub->descriptor->bPwrOn2PwrGood * 2);
786
787 /* power budgeting mostly matters with bus-powered hubs,
788 * and battery-powered root hubs (may provide just 8 mA).
789 */
790 ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
791 if (ret < 2) {
792 message = "can't get hub status";
793 goto fail;
794 }
795 le16_to_cpus(&hubstatus);
796 if (hdev == hdev->bus->root_hub) {
797 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
798 hub->mA_per_port = 500;
799 else {
800 hub->mA_per_port = hdev->bus_mA;
801 hub->limited_power = 1;
802 }
803 } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
804 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
805 hub->descriptor->bHubContrCurrent);
806 hub->limited_power = 1;
807 if (hdev->maxchild > 0) {
808 int remaining = hdev->bus_mA -
809 hub->descriptor->bHubContrCurrent;
810
811 if (remaining < hdev->maxchild * 100)
812 dev_warn(hub_dev,
813 "insufficient power available "
814 "to use all downstream ports\n");
815 hub->mA_per_port = 100; /* 7.2.1.1 */
816 }
817 } else { /* Self-powered external hub */
818 /* FIXME: What about battery-powered external hubs that
819 * provide less current per port? */
820 hub->mA_per_port = 500;
821 }
822 if (hub->mA_per_port < 500)
823 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
824 hub->mA_per_port);
825
826 ret = hub_hub_status(hub, &hubstatus, &hubchange);
827 if (ret < 0) {
828 message = "can't get hub status";
829 goto fail;
830 }
831
832 /* local power status reports aren't always correct */
833 if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
834 dev_dbg(hub_dev, "local power source is %s\n",
835 (hubstatus & HUB_STATUS_LOCAL_POWER)
836 ? "lost (inactive)" : "good");
837
838 if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
839 dev_dbg(hub_dev, "%sover-current condition exists\n",
840 (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
841
842 /* set up the interrupt endpoint
843 * We use the EP's maxpacket size instead of (PORTS+1+7)/8
844 * bytes as USB2.0[11.12.3] says because some hubs are known
845 * to send more data (and thus cause overflow). For root hubs,
846 * maxpktsize is defined in hcd.c's fake endpoint descriptors
847 * to be big enough for at least USB_MAXCHILDREN ports. */
848 pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
849 maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
850
851 if (maxp > sizeof(*hub->buffer))
852 maxp = sizeof(*hub->buffer);
853
854 hub->urb = usb_alloc_urb(0, GFP_KERNEL);
855 if (!hub->urb) {
856 message = "couldn't allocate interrupt urb";
857 ret = -ENOMEM;
858 goto fail;
859 }
860
861 usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
862 hub, endpoint->bInterval);
863 hub->urb->transfer_dma = hub->buffer_dma;
864 hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
865
866 /* maybe cycle the hub leds */
867 if (hub->has_indicators && blinkenlights)
868 hub->indicator [0] = INDICATOR_CYCLE;
869
870 hub_power_on(hub);
871 hub_activate(hub);
872 return 0;
873
874 fail:
875 dev_err (hub_dev, "config failed, %s (err %d)\n",
876 message, ret);
877 /* hub_disconnect() frees urb and descriptor */
878 return ret;
879 }
880
881 static void hub_release(struct kref *kref)
882 {
883 struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
884
885 usb_put_intf(to_usb_interface(hub->intfdev));
886 kfree(hub);
887 }
888
889 static unsigned highspeed_hubs;
890
891 static void hub_disconnect(struct usb_interface *intf)
892 {
893 struct usb_hub *hub = usb_get_intfdata (intf);
894
895 /* Take the hub off the event list and don't let it be added again */
896 spin_lock_irq(&hub_event_lock);
897 list_del_init(&hub->event_list);
898 hub->disconnected = 1;
899 spin_unlock_irq(&hub_event_lock);
900
901 /* Disconnect all children and quiesce the hub */
902 hub->error = 0;
903 hub_pre_reset(intf);
904
905 usb_set_intfdata (intf, NULL);
906
907 if (hub->hdev->speed == USB_SPEED_HIGH)
908 highspeed_hubs--;
909
910 usb_free_urb(hub->urb);
911 kfree(hub->descriptor);
912 kfree(hub->status);
913 usb_buffer_free(hub->hdev, sizeof(*hub->buffer), hub->buffer,
914 hub->buffer_dma);
915
916 kref_put(&hub->kref, hub_release);
917 }
918
919 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
920 {
921 struct usb_host_interface *desc;
922 struct usb_endpoint_descriptor *endpoint;
923 struct usb_device *hdev;
924 struct usb_hub *hub;
925
926 desc = intf->cur_altsetting;
927 hdev = interface_to_usbdev(intf);
928
929 #ifdef CONFIG_USB_OTG_BLACKLIST_HUB
930 if (hdev->parent) {
931 dev_warn(&intf->dev, "ignoring external hub\n");
932 return -ENODEV;
933 }
934 #endif
935
936 /* Some hubs have a subclass of 1, which AFAICT according to the */
937 /* specs is not defined, but it works */
938 if ((desc->desc.bInterfaceSubClass != 0) &&
939 (desc->desc.bInterfaceSubClass != 1)) {
940 descriptor_error:
941 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
942 return -EIO;
943 }
944
945 /* Multiple endpoints? What kind of mutant ninja-hub is this? */
946 if (desc->desc.bNumEndpoints != 1)
947 goto descriptor_error;
948
949 endpoint = &desc->endpoint[0].desc;
950
951 /* If it's not an interrupt in endpoint, we'd better punt! */
952 if (!usb_endpoint_is_int_in(endpoint))
953 goto descriptor_error;
954
955 /* We found a hub */
956 dev_info (&intf->dev, "USB hub found\n");
957
958 hub = kzalloc(sizeof(*hub), GFP_KERNEL);
959 if (!hub) {
960 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
961 return -ENOMEM;
962 }
963
964 kref_init(&hub->kref);
965 INIT_LIST_HEAD(&hub->event_list);
966 hub->intfdev = &intf->dev;
967 hub->hdev = hdev;
968 INIT_DELAYED_WORK(&hub->leds, led_work);
969 usb_get_intf(intf);
970
971 usb_set_intfdata (intf, hub);
972 intf->needs_remote_wakeup = 1;
973
974 if (hdev->speed == USB_SPEED_HIGH)
975 highspeed_hubs++;
976
977 if (hub_configure(hub, endpoint) >= 0)
978 return 0;
979
980 hub_disconnect (intf);
981 return -ENODEV;
982 }
983
984 static int
985 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
986 {
987 struct usb_device *hdev = interface_to_usbdev (intf);
988
989 /* assert ifno == 0 (part of hub spec) */
990 switch (code) {
991 case USBDEVFS_HUB_PORTINFO: {
992 struct usbdevfs_hub_portinfo *info = user_data;
993 int i;
994
995 spin_lock_irq(&device_state_lock);
996 if (hdev->devnum <= 0)
997 info->nports = 0;
998 else {
999 info->nports = hdev->maxchild;
1000 for (i = 0; i < info->nports; i++) {
1001 if (hdev->children[i] == NULL)
1002 info->port[i] = 0;
1003 else
1004 info->port[i] =
1005 hdev->children[i]->devnum;
1006 }
1007 }
1008 spin_unlock_irq(&device_state_lock);
1009
1010 return info->nports + 1;
1011 }
1012
1013 default:
1014 return -ENOSYS;
1015 }
1016 }
1017
1018
1019 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1020 {
1021 int i;
1022
1023 for (i = 0; i < udev->maxchild; ++i) {
1024 if (udev->children[i])
1025 recursively_mark_NOTATTACHED(udev->children[i]);
1026 }
1027 if (udev->state == USB_STATE_SUSPENDED)
1028 udev->discon_suspended = 1;
1029 udev->state = USB_STATE_NOTATTACHED;
1030 }
1031
1032 /**
1033 * usb_set_device_state - change a device's current state (usbcore, hcds)
1034 * @udev: pointer to device whose state should be changed
1035 * @new_state: new state value to be stored
1036 *
1037 * udev->state is _not_ fully protected by the device lock. Although
1038 * most transitions are made only while holding the lock, the state can
1039 * can change to USB_STATE_NOTATTACHED at almost any time. This
1040 * is so that devices can be marked as disconnected as soon as possible,
1041 * without having to wait for any semaphores to be released. As a result,
1042 * all changes to any device's state must be protected by the
1043 * device_state_lock spinlock.
1044 *
1045 * Once a device has been added to the device tree, all changes to its state
1046 * should be made using this routine. The state should _not_ be set directly.
1047 *
1048 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1049 * Otherwise udev->state is set to new_state, and if new_state is
1050 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1051 * to USB_STATE_NOTATTACHED.
1052 */
1053 void usb_set_device_state(struct usb_device *udev,
1054 enum usb_device_state new_state)
1055 {
1056 unsigned long flags;
1057
1058 spin_lock_irqsave(&device_state_lock, flags);
1059 if (udev->state == USB_STATE_NOTATTACHED)
1060 ; /* do nothing */
1061 else if (new_state != USB_STATE_NOTATTACHED) {
1062
1063 /* root hub wakeup capabilities are managed out-of-band
1064 * and may involve silicon errata ... ignore them here.
1065 */
1066 if (udev->parent) {
1067 if (udev->state == USB_STATE_SUSPENDED
1068 || new_state == USB_STATE_SUSPENDED)
1069 ; /* No change to wakeup settings */
1070 else if (new_state == USB_STATE_CONFIGURED)
1071 device_init_wakeup(&udev->dev,
1072 (udev->actconfig->desc.bmAttributes
1073 & USB_CONFIG_ATT_WAKEUP));
1074 else
1075 device_init_wakeup(&udev->dev, 0);
1076 }
1077 udev->state = new_state;
1078 } else
1079 recursively_mark_NOTATTACHED(udev);
1080 spin_unlock_irqrestore(&device_state_lock, flags);
1081 }
1082
1083
1084 #ifdef CONFIG_PM
1085
1086 /**
1087 * usb_reset_suspended_device - reset a suspended device instead of resuming it
1088 * @udev: device to be reset instead of resumed
1089 *
1090 * If a host controller doesn't maintain VBUS suspend current during a
1091 * system sleep or is reset when the system wakes up, all the USB
1092 * power sessions below it will be broken. This is especially troublesome
1093 * for mass-storage devices containing mounted filesystems, since the
1094 * device will appear to have disconnected and all the memory mappings
1095 * to it will be lost.
1096 *
1097 * As an alternative, this routine attempts to recover power sessions for
1098 * devices that are still present by resetting them instead of resuming
1099 * them. If all goes well, the devices will appear to persist across the
1100 * the interruption of the power sessions.
1101 *
1102 * This facility is inherently dangerous. Although usb_reset_device()
1103 * makes every effort to insure that the same device is present after the
1104 * reset as before, it cannot provide a 100% guarantee. Furthermore it's
1105 * quite possible for a device to remain unaltered but its media to be
1106 * changed. If the user replaces a flash memory card while the system is
1107 * asleep, he will have only himself to blame when the filesystem on the
1108 * new card is corrupted and the system crashes.
1109 */
1110 int usb_reset_suspended_device(struct usb_device *udev)
1111 {
1112 int rc = 0;
1113
1114 dev_dbg(&udev->dev, "usb %sresume\n", "reset-");
1115
1116 /* After we're done the device won't be suspended any more.
1117 * In addition, the reset won't work if udev->state is SUSPENDED.
1118 */
1119 usb_set_device_state(udev, udev->actconfig
1120 ? USB_STATE_CONFIGURED
1121 : USB_STATE_ADDRESS);
1122
1123 /* Root hubs don't need to be (and can't be) reset */
1124 if (udev->parent)
1125 rc = usb_reset_device(udev);
1126 return rc;
1127 }
1128
1129 /**
1130 * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
1131 * @rhdev: struct usb_device for the root hub
1132 *
1133 * The USB host controller driver calls this function when its root hub
1134 * is resumed and Vbus power has been interrupted or the controller
1135 * has been reset. The routine marks @rhdev as having lost power. When
1136 * the hub driver is resumed it will take notice; if CONFIG_USB_PERSIST
1137 * is enabled then it will carry out power-session recovery, otherwise
1138 * it will disconnect all the child devices.
1139 */
1140 void usb_root_hub_lost_power(struct usb_device *rhdev)
1141 {
1142 dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
1143 rhdev->reset_resume = 1;
1144 }
1145 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
1146
1147 #endif /* CONFIG_PM */
1148
1149 static void choose_address(struct usb_device *udev)
1150 {
1151 int devnum;
1152 struct usb_bus *bus = udev->bus;
1153
1154 /* If khubd ever becomes multithreaded, this will need a lock */
1155
1156 /* Try to allocate the next devnum beginning at bus->devnum_next. */
1157 devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1158 bus->devnum_next);
1159 if (devnum >= 128)
1160 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1161
1162 bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1163
1164 if (devnum < 128) {
1165 set_bit(devnum, bus->devmap.devicemap);
1166 udev->devnum = devnum;
1167 }
1168 }
1169
1170 static void release_address(struct usb_device *udev)
1171 {
1172 if (udev->devnum > 0) {
1173 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1174 udev->devnum = -1;
1175 }
1176 }
1177
1178 #ifdef CONFIG_USB_SUSPEND
1179
1180 static void usb_stop_pm(struct usb_device *udev)
1181 {
1182 /* Synchronize with the ksuspend thread to prevent any more
1183 * autosuspend requests from being submitted, and decrement
1184 * the parent's count of unsuspended children.
1185 */
1186 usb_pm_lock(udev);
1187 if (udev->parent && !udev->discon_suspended)
1188 usb_autosuspend_device(udev->parent);
1189 usb_pm_unlock(udev);
1190
1191 /* Stop any autosuspend requests already submitted */
1192 cancel_rearming_delayed_work(&udev->autosuspend);
1193 }
1194
1195 #else
1196
1197 static inline void usb_stop_pm(struct usb_device *udev)
1198 { }
1199
1200 #endif
1201
1202 /**
1203 * usb_disconnect - disconnect a device (usbcore-internal)
1204 * @pdev: pointer to device being disconnected
1205 * Context: !in_interrupt ()
1206 *
1207 * Something got disconnected. Get rid of it and all of its children.
1208 *
1209 * If *pdev is a normal device then the parent hub must already be locked.
1210 * If *pdev is a root hub then this routine will acquire the
1211 * usb_bus_list_lock on behalf of the caller.
1212 *
1213 * Only hub drivers (including virtual root hub drivers for host
1214 * controllers) should ever call this.
1215 *
1216 * This call is synchronous, and may not be used in an interrupt context.
1217 */
1218 void usb_disconnect(struct usb_device **pdev)
1219 {
1220 struct usb_device *udev = *pdev;
1221 int i;
1222
1223 if (!udev) {
1224 pr_debug ("%s nodev\n", __FUNCTION__);
1225 return;
1226 }
1227
1228 /* mark the device as inactive, so any further urb submissions for
1229 * this device (and any of its children) will fail immediately.
1230 * this quiesces everyting except pending urbs.
1231 */
1232 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1233 dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1234
1235 usb_lock_device(udev);
1236
1237 /* Free up all the children before we remove this device */
1238 for (i = 0; i < USB_MAXCHILDREN; i++) {
1239 if (udev->children[i])
1240 usb_disconnect(&udev->children[i]);
1241 }
1242
1243 /* deallocate hcd/hardware state ... nuking all pending urbs and
1244 * cleaning up all state associated with the current configuration
1245 * so that the hardware is now fully quiesced.
1246 */
1247 dev_dbg (&udev->dev, "unregistering device\n");
1248 usb_disable_device(udev, 0);
1249
1250 usb_unlock_device(udev);
1251
1252 /* Unregister the device. The device driver is responsible
1253 * for removing the device files from usbfs and sysfs and for
1254 * de-configuring the device.
1255 */
1256 device_del(&udev->dev);
1257
1258 /* Free the device number and delete the parent's children[]
1259 * (or root_hub) pointer.
1260 */
1261 release_address(udev);
1262
1263 /* Avoid races with recursively_mark_NOTATTACHED() */
1264 spin_lock_irq(&device_state_lock);
1265 *pdev = NULL;
1266 spin_unlock_irq(&device_state_lock);
1267
1268 usb_stop_pm(udev);
1269
1270 put_device(&udev->dev);
1271 }
1272
1273 #ifdef DEBUG
1274 static void show_string(struct usb_device *udev, char *id, char *string)
1275 {
1276 if (!string)
1277 return;
1278 dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1279 }
1280
1281 #else
1282 static inline void show_string(struct usb_device *udev, char *id, char *string)
1283 {}
1284 #endif
1285
1286
1287 #ifdef CONFIG_USB_OTG
1288 #include "otg_whitelist.h"
1289 #endif
1290
1291 /**
1292 * usb_new_device - perform initial device setup (usbcore-internal)
1293 * @udev: newly addressed device (in ADDRESS state)
1294 *
1295 * This is called with devices which have been enumerated, but not yet
1296 * configured. The device descriptor is available, but not descriptors
1297 * for any device configuration. The caller must have locked either
1298 * the parent hub (if udev is a normal device) or else the
1299 * usb_bus_list_lock (if udev is a root hub). The parent's pointer to
1300 * udev has already been installed, but udev is not yet visible through
1301 * sysfs or other filesystem code.
1302 *
1303 * It will return if the device is configured properly or not. Zero if
1304 * the interface was registered with the driver core; else a negative
1305 * errno value.
1306 *
1307 * This call is synchronous, and may not be used in an interrupt context.
1308 *
1309 * Only the hub driver or root-hub registrar should ever call this.
1310 */
1311 int usb_new_device(struct usb_device *udev)
1312 {
1313 int err;
1314
1315 /* Determine quirks */
1316 usb_detect_quirks(udev);
1317
1318 err = usb_get_configuration(udev);
1319 if (err < 0) {
1320 dev_err(&udev->dev, "can't read configurations, error %d\n",
1321 err);
1322 goto fail;
1323 }
1324
1325 /* read the standard strings and cache them if present */
1326 udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1327 udev->manufacturer = usb_cache_string(udev,
1328 udev->descriptor.iManufacturer);
1329 udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1330
1331 /* Tell the world! */
1332 dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1333 "SerialNumber=%d\n",
1334 udev->descriptor.iManufacturer,
1335 udev->descriptor.iProduct,
1336 udev->descriptor.iSerialNumber);
1337 show_string(udev, "Product", udev->product);
1338 show_string(udev, "Manufacturer", udev->manufacturer);
1339 show_string(udev, "SerialNumber", udev->serial);
1340
1341 #ifdef CONFIG_USB_OTG
1342 /*
1343 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1344 * to wake us after we've powered off VBUS; and HNP, switching roles
1345 * "host" to "peripheral". The OTG descriptor helps figure this out.
1346 */
1347 if (!udev->bus->is_b_host
1348 && udev->config
1349 && udev->parent == udev->bus->root_hub) {
1350 struct usb_otg_descriptor *desc = 0;
1351 struct usb_bus *bus = udev->bus;
1352
1353 /* descriptor may appear anywhere in config */
1354 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1355 le16_to_cpu(udev->config[0].desc.wTotalLength),
1356 USB_DT_OTG, (void **) &desc) == 0) {
1357 if (desc->bmAttributes & USB_OTG_HNP) {
1358 unsigned port1 = udev->portnum;
1359
1360 dev_info(&udev->dev,
1361 "Dual-Role OTG device on %sHNP port\n",
1362 (port1 == bus->otg_port)
1363 ? "" : "non-");
1364
1365 /* enable HNP before suspend, it's simpler */
1366 if (port1 == bus->otg_port)
1367 bus->b_hnp_enable = 1;
1368 err = usb_control_msg(udev,
1369 usb_sndctrlpipe(udev, 0),
1370 USB_REQ_SET_FEATURE, 0,
1371 bus->b_hnp_enable
1372 ? USB_DEVICE_B_HNP_ENABLE
1373 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1374 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1375 if (err < 0) {
1376 /* OTG MESSAGE: report errors here,
1377 * customize to match your product.
1378 */
1379 dev_info(&udev->dev,
1380 "can't set HNP mode; %d\n",
1381 err);
1382 bus->b_hnp_enable = 0;
1383 }
1384 }
1385 }
1386 }
1387
1388 if (!is_targeted(udev)) {
1389
1390 /* Maybe it can talk to us, though we can't talk to it.
1391 * (Includes HNP test device.)
1392 */
1393 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1394 err = usb_port_suspend(udev);
1395 if (err < 0)
1396 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1397 }
1398 err = -ENOTSUPP;
1399 goto fail;
1400 }
1401 #endif
1402
1403 /* export the usbdev device-node for libusb */
1404 udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
1405 (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
1406
1407 /* Register the device. The device driver is responsible
1408 * for adding the device files to sysfs and for configuring
1409 * the device.
1410 */
1411 err = device_add(&udev->dev);
1412 if (err) {
1413 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1414 goto fail;
1415 }
1416
1417 /* Increment the parent's count of unsuspended children */
1418 if (udev->parent)
1419 usb_autoresume_device(udev->parent);
1420
1421 exit:
1422 return err;
1423
1424 fail:
1425 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1426 goto exit;
1427 }
1428
1429 static int hub_port_status(struct usb_hub *hub, int port1,
1430 u16 *status, u16 *change)
1431 {
1432 int ret;
1433
1434 mutex_lock(&hub->status_mutex);
1435 ret = get_port_status(hub->hdev, port1, &hub->status->port);
1436 if (ret < 4) {
1437 dev_err (hub->intfdev,
1438 "%s failed (err = %d)\n", __FUNCTION__, ret);
1439 if (ret >= 0)
1440 ret = -EIO;
1441 } else {
1442 *status = le16_to_cpu(hub->status->port.wPortStatus);
1443 *change = le16_to_cpu(hub->status->port.wPortChange);
1444 ret = 0;
1445 }
1446 mutex_unlock(&hub->status_mutex);
1447 return ret;
1448 }
1449
1450
1451 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
1452 static unsigned hub_is_wusb(struct usb_hub *hub)
1453 {
1454 struct usb_hcd *hcd;
1455 if (hub->hdev->parent != NULL) /* not a root hub? */
1456 return 0;
1457 hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
1458 return hcd->wireless;
1459 }
1460
1461
1462 #define PORT_RESET_TRIES 5
1463 #define SET_ADDRESS_TRIES 2
1464 #define GET_DESCRIPTOR_TRIES 2
1465 #define SET_CONFIG_TRIES (2 * (use_both_schemes + 1))
1466 #define USE_NEW_SCHEME(i) ((i) / 2 == old_scheme_first)
1467
1468 #define HUB_ROOT_RESET_TIME 50 /* times are in msec */
1469 #define HUB_SHORT_RESET_TIME 10
1470 #define HUB_LONG_RESET_TIME 200
1471 #define HUB_RESET_TIMEOUT 500
1472
1473 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1474 struct usb_device *udev, unsigned int delay)
1475 {
1476 int delay_time, ret;
1477 u16 portstatus;
1478 u16 portchange;
1479
1480 for (delay_time = 0;
1481 delay_time < HUB_RESET_TIMEOUT;
1482 delay_time += delay) {
1483 /* wait to give the device a chance to reset */
1484 msleep(delay);
1485
1486 /* read and decode port status */
1487 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1488 if (ret < 0)
1489 return ret;
1490
1491 /* Device went away? */
1492 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1493 return -ENOTCONN;
1494
1495 /* bomb out completely if the connection bounced */
1496 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1497 return -ENOTCONN;
1498
1499 /* if we`ve finished resetting, then break out of the loop */
1500 if (!(portstatus & USB_PORT_STAT_RESET) &&
1501 (portstatus & USB_PORT_STAT_ENABLE)) {
1502 if (hub_is_wusb(hub))
1503 udev->speed = USB_SPEED_VARIABLE;
1504 else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1505 udev->speed = USB_SPEED_HIGH;
1506 else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1507 udev->speed = USB_SPEED_LOW;
1508 else
1509 udev->speed = USB_SPEED_FULL;
1510 return 0;
1511 }
1512
1513 /* switch to the long delay after two short delay failures */
1514 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1515 delay = HUB_LONG_RESET_TIME;
1516
1517 dev_dbg (hub->intfdev,
1518 "port %d not reset yet, waiting %dms\n",
1519 port1, delay);
1520 }
1521
1522 return -EBUSY;
1523 }
1524
1525 static int hub_port_reset(struct usb_hub *hub, int port1,
1526 struct usb_device *udev, unsigned int delay)
1527 {
1528 int i, status;
1529
1530 /* Reset the port */
1531 for (i = 0; i < PORT_RESET_TRIES; i++) {
1532 status = set_port_feature(hub->hdev,
1533 port1, USB_PORT_FEAT_RESET);
1534 if (status)
1535 dev_err(hub->intfdev,
1536 "cannot reset port %d (err = %d)\n",
1537 port1, status);
1538 else {
1539 status = hub_port_wait_reset(hub, port1, udev, delay);
1540 if (status && status != -ENOTCONN)
1541 dev_dbg(hub->intfdev,
1542 "port_wait_reset: err = %d\n",
1543 status);
1544 }
1545
1546 /* return on disconnect or reset */
1547 switch (status) {
1548 case 0:
1549 /* TRSTRCY = 10 ms; plus some extra */
1550 msleep(10 + 40);
1551 /* FALL THROUGH */
1552 case -ENOTCONN:
1553 case -ENODEV:
1554 clear_port_feature(hub->hdev,
1555 port1, USB_PORT_FEAT_C_RESET);
1556 /* FIXME need disconnect() for NOTATTACHED device */
1557 usb_set_device_state(udev, status
1558 ? USB_STATE_NOTATTACHED
1559 : USB_STATE_DEFAULT);
1560 return status;
1561 }
1562
1563 dev_dbg (hub->intfdev,
1564 "port %d not enabled, trying reset again...\n",
1565 port1);
1566 delay = HUB_LONG_RESET_TIME;
1567 }
1568
1569 dev_err (hub->intfdev,
1570 "Cannot enable port %i. Maybe the USB cable is bad?\n",
1571 port1);
1572
1573 return status;
1574 }
1575
1576 #ifdef CONFIG_PM
1577
1578 #ifdef CONFIG_USB_SUSPEND
1579
1580 /*
1581 * usb_port_suspend - suspend a usb device's upstream port
1582 * @udev: device that's no longer in active use, not a root hub
1583 * Context: must be able to sleep; device not locked; pm locks held
1584 *
1585 * Suspends a USB device that isn't in active use, conserving power.
1586 * Devices may wake out of a suspend, if anything important happens,
1587 * using the remote wakeup mechanism. They may also be taken out of
1588 * suspend by the host, using usb_port_resume(). It's also routine
1589 * to disconnect devices while they are suspended.
1590 *
1591 * This only affects the USB hardware for a device; its interfaces
1592 * (and, for hubs, child devices) must already have been suspended.
1593 *
1594 * Selective port suspend reduces power; most suspended devices draw
1595 * less than 500 uA. It's also used in OTG, along with remote wakeup.
1596 * All devices below the suspended port are also suspended.
1597 *
1598 * Devices leave suspend state when the host wakes them up. Some devices
1599 * also support "remote wakeup", where the device can activate the USB
1600 * tree above them to deliver data, such as a keypress or packet. In
1601 * some cases, this wakes the USB host.
1602 *
1603 * Suspending OTG devices may trigger HNP, if that's been enabled
1604 * between a pair of dual-role devices. That will change roles, such
1605 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1606 *
1607 * Devices on USB hub ports have only one "suspend" state, corresponding
1608 * to ACPI D2, "may cause the device to lose some context".
1609 * State transitions include:
1610 *
1611 * - suspend, resume ... when the VBUS power link stays live
1612 * - suspend, disconnect ... VBUS lost
1613 *
1614 * Once VBUS drop breaks the circuit, the port it's using has to go through
1615 * normal re-enumeration procedures, starting with enabling VBUS power.
1616 * Other than re-initializing the hub (plug/unplug, except for root hubs),
1617 * Linux (2.6) currently has NO mechanisms to initiate that: no khubd
1618 * timer, no SRP, no requests through sysfs.
1619 *
1620 * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1621 * the root hub for their bus goes into global suspend ... so we don't
1622 * (falsely) update the device power state to say it suspended.
1623 *
1624 * Returns 0 on success, else negative errno.
1625 */
1626 int usb_port_suspend(struct usb_device *udev)
1627 {
1628 struct usb_hub *hub = hdev_to_hub(udev->parent);
1629 int port1 = udev->portnum;
1630 int status;
1631
1632 // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1633
1634 /* enable remote wakeup when appropriate; this lets the device
1635 * wake up the upstream hub (including maybe the root hub).
1636 *
1637 * NOTE: OTG devices may issue remote wakeup (or SRP) even when
1638 * we don't explicitly enable it here.
1639 */
1640 if (udev->do_remote_wakeup) {
1641 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1642 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1643 USB_DEVICE_REMOTE_WAKEUP, 0,
1644 NULL, 0,
1645 USB_CTRL_SET_TIMEOUT);
1646 if (status)
1647 dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
1648 status);
1649 }
1650
1651 /* see 7.1.7.6 */
1652 status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1653 if (status) {
1654 dev_dbg(hub->intfdev, "can't suspend port %d, status %d\n",
1655 port1, status);
1656 /* paranoia: "should not happen" */
1657 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1658 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1659 USB_DEVICE_REMOTE_WAKEUP, 0,
1660 NULL, 0,
1661 USB_CTRL_SET_TIMEOUT);
1662 } else {
1663 /* device has up to 10 msec to fully suspend */
1664 dev_dbg(&udev->dev, "usb %ssuspend\n",
1665 udev->auto_pm ? "auto-" : "");
1666 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1667 msleep(10);
1668 }
1669 return status;
1670 }
1671
1672 /*
1673 * If the USB "suspend" state is in use (rather than "global suspend"),
1674 * many devices will be individually taken out of suspend state using
1675 * special" resume" signaling. These routines kick in shortly after
1676 * hardware resume signaling is finished, either because of selective
1677 * resume (by host) or remote wakeup (by device) ... now see what changed
1678 * in the tree that's rooted at this device.
1679 */
1680 static int finish_port_resume(struct usb_device *udev)
1681 {
1682 int status;
1683 u16 devstatus;
1684
1685 /* caller owns the udev device lock */
1686 dev_dbg(&udev->dev, "finish resume\n");
1687
1688 /* usb ch9 identifies four variants of SUSPENDED, based on what
1689 * state the device resumes to. Linux currently won't see the
1690 * first two on the host side; they'd be inside hub_port_init()
1691 * during many timeouts, but khubd can't suspend until later.
1692 */
1693 usb_set_device_state(udev, udev->actconfig
1694 ? USB_STATE_CONFIGURED
1695 : USB_STATE_ADDRESS);
1696
1697 /* 10.5.4.5 says be sure devices in the tree are still there.
1698 * For now let's assume the device didn't go crazy on resume,
1699 * and device drivers will know about any resume quirks.
1700 */
1701 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1702 if (status >= 0)
1703 status = (status == 2 ? 0 : -ENODEV);
1704
1705 if (status) {
1706 dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
1707 status);
1708 } else if (udev->actconfig) {
1709 le16_to_cpus(&devstatus);
1710 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
1711 status = usb_control_msg(udev,
1712 usb_sndctrlpipe(udev, 0),
1713 USB_REQ_CLEAR_FEATURE,
1714 USB_RECIP_DEVICE,
1715 USB_DEVICE_REMOTE_WAKEUP, 0,
1716 NULL, 0,
1717 USB_CTRL_SET_TIMEOUT);
1718 if (status)
1719 dev_dbg(&udev->dev, "disable remote "
1720 "wakeup, status %d\n", status);
1721 }
1722 status = 0;
1723 }
1724 return status;
1725 }
1726
1727 /*
1728 * usb_port_resume - re-activate a suspended usb device's upstream port
1729 * @udev: device to re-activate, not a root hub
1730 * Context: must be able to sleep; device not locked; pm locks held
1731 *
1732 * This will re-activate the suspended device, increasing power usage
1733 * while letting drivers communicate again with its endpoints.
1734 * USB resume explicitly guarantees that the power session between
1735 * the host and the device is the same as it was when the device
1736 * suspended.
1737 *
1738 * Returns 0 on success, else negative errno.
1739 */
1740 int usb_port_resume(struct usb_device *udev)
1741 {
1742 struct usb_hub *hub = hdev_to_hub(udev->parent);
1743 int port1 = udev->portnum;
1744 int status;
1745 u16 portchange, portstatus;
1746
1747 /* Skip the initial Clear-Suspend step for a remote wakeup */
1748 status = hub_port_status(hub, port1, &portstatus, &portchange);
1749 if (status == 0 && !(portstatus & USB_PORT_STAT_SUSPEND))
1750 goto SuspendCleared;
1751
1752 // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1753
1754 set_bit(port1, hub->busy_bits);
1755
1756 /* see 7.1.7.7; affects power usage, but not budgeting */
1757 status = clear_port_feature(hub->hdev,
1758 port1, USB_PORT_FEAT_SUSPEND);
1759 if (status) {
1760 dev_dbg(hub->intfdev, "can't resume port %d, status %d\n",
1761 port1, status);
1762 } else {
1763 /* drive resume for at least 20 msec */
1764 dev_dbg(&udev->dev, "usb %sresume\n",
1765 udev->auto_pm ? "auto-" : "");
1766 msleep(25);
1767
1768 #define LIVE_FLAGS ( USB_PORT_STAT_POWER \
1769 | USB_PORT_STAT_ENABLE \
1770 | USB_PORT_STAT_CONNECTION)
1771
1772 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1773 * stop resume signaling. Then finish the resume
1774 * sequence.
1775 */
1776 status = hub_port_status(hub, port1, &portstatus, &portchange);
1777 SuspendCleared:
1778 if (status < 0
1779 || (portstatus & LIVE_FLAGS) != LIVE_FLAGS
1780 || (portstatus & USB_PORT_STAT_SUSPEND) != 0
1781 ) {
1782 dev_dbg(hub->intfdev,
1783 "port %d status %04x.%04x after resume, %d\n",
1784 port1, portchange, portstatus, status);
1785 if (status >= 0)
1786 status = -ENODEV;
1787 } else {
1788 if (portchange & USB_PORT_STAT_C_SUSPEND)
1789 clear_port_feature(hub->hdev, port1,
1790 USB_PORT_FEAT_C_SUSPEND);
1791 /* TRSMRCY = 10 msec */
1792 msleep(10);
1793 status = finish_port_resume(udev);
1794 }
1795 }
1796 if (status < 0) {
1797 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
1798 hub_port_logical_disconnect(hub, port1);
1799 }
1800
1801 clear_bit(port1, hub->busy_bits);
1802 if (!hub->hdev->parent && !hub->busy_bits[0])
1803 usb_enable_root_hub_irq(hub->hdev->bus);
1804
1805 return status;
1806 }
1807
1808 static int remote_wakeup(struct usb_device *udev)
1809 {
1810 int status = 0;
1811
1812 usb_lock_device(udev);
1813 if (udev->state == USB_STATE_SUSPENDED) {
1814 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
1815 usb_mark_last_busy(udev);
1816 status = usb_external_resume_device(udev);
1817 }
1818 usb_unlock_device(udev);
1819 return status;
1820 }
1821
1822 #else /* CONFIG_USB_SUSPEND */
1823
1824 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
1825
1826 int usb_port_suspend(struct usb_device *udev)
1827 {
1828 return 0;
1829 }
1830
1831 int usb_port_resume(struct usb_device *udev)
1832 {
1833 return 0;
1834 }
1835
1836 static inline int remote_wakeup(struct usb_device *udev)
1837 {
1838 return 0;
1839 }
1840
1841 #endif
1842
1843 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
1844 {
1845 struct usb_hub *hub = usb_get_intfdata (intf);
1846 struct usb_device *hdev = hub->hdev;
1847 unsigned port1;
1848
1849 /* fail if children aren't already suspended */
1850 for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1851 struct usb_device *udev;
1852
1853 udev = hdev->children [port1-1];
1854 if (udev && msg.event == PM_EVENT_SUSPEND &&
1855 #ifdef CONFIG_USB_SUSPEND
1856 udev->state != USB_STATE_SUSPENDED
1857 #else
1858 udev->dev.power.power_state.event
1859 == PM_EVENT_ON
1860 #endif
1861 ) {
1862 if (!hdev->auto_pm)
1863 dev_dbg(&intf->dev, "port %d nyet suspended\n",
1864 port1);
1865 return -EBUSY;
1866 }
1867 }
1868
1869 dev_dbg(&intf->dev, "%s\n", __FUNCTION__);
1870
1871 /* stop khubd and related activity */
1872 hub_quiesce(hub);
1873 return 0;
1874 }
1875
1876 static int hub_resume(struct usb_interface *intf)
1877 {
1878 struct usb_hub *hub = usb_get_intfdata (intf);
1879
1880 dev_dbg(&intf->dev, "%s\n", __FUNCTION__);
1881
1882 /* tell khubd to look for changes on this hub */
1883 hub_activate(hub);
1884 return 0;
1885 }
1886
1887 #ifdef CONFIG_USB_PERSIST
1888
1889 #define USB_PERSIST 1
1890
1891 /* For "persistent-device" resets we must mark the child devices for reset
1892 * and turn off a possible connect-change status (so khubd won't disconnect
1893 * them later).
1894 */
1895 static void mark_children_for_reset_resume(struct usb_hub *hub)
1896 {
1897 struct usb_device *hdev = hub->hdev;
1898 int port1;
1899
1900 for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
1901 struct usb_device *child = hdev->children[port1-1];
1902
1903 if (child) {
1904 child->reset_resume = 1;
1905 clear_port_feature(hdev, port1,
1906 USB_PORT_FEAT_C_CONNECTION);
1907 }
1908 }
1909 }
1910
1911 #else
1912
1913 #define USB_PERSIST 0
1914
1915 static inline void mark_children_for_reset_resume(struct usb_hub *hub)
1916 { }
1917
1918 #endif /* CONFIG_USB_PERSIST */
1919
1920 static int hub_reset_resume(struct usb_interface *intf)
1921 {
1922 struct usb_hub *hub = usb_get_intfdata(intf);
1923
1924 hub_power_on(hub);
1925 if (USB_PERSIST)
1926 mark_children_for_reset_resume(hub);
1927 else {
1928 /* Reset-resume doesn't call pre_reset, so we have to
1929 * disconnect the children here. But we may not lock
1930 * the child devices, so we have to do a "logical"
1931 * disconnect.
1932 */
1933 disconnect_all_children(hub, 1);
1934 }
1935 hub_activate(hub);
1936 return 0;
1937 }
1938
1939 #else /* CONFIG_PM */
1940
1941 static inline int remote_wakeup(struct usb_device *udev)
1942 {
1943 return 0;
1944 }
1945
1946 #define hub_suspend NULL
1947 #define hub_resume NULL
1948 #define hub_reset_resume NULL
1949 #endif
1950
1951
1952 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
1953 *
1954 * Between connect detection and reset signaling there must be a delay
1955 * of 100ms at least for debounce and power-settling. The corresponding
1956 * timer shall restart whenever the downstream port detects a disconnect.
1957 *
1958 * Apparently there are some bluetooth and irda-dongles and a number of
1959 * low-speed devices for which this debounce period may last over a second.
1960 * Not covered by the spec - but easy to deal with.
1961 *
1962 * This implementation uses a 1500ms total debounce timeout; if the
1963 * connection isn't stable by then it returns -ETIMEDOUT. It checks
1964 * every 25ms for transient disconnects. When the port status has been
1965 * unchanged for 100ms it returns the port status.
1966 */
1967
1968 #define HUB_DEBOUNCE_TIMEOUT 1500
1969 #define HUB_DEBOUNCE_STEP 25
1970 #define HUB_DEBOUNCE_STABLE 100
1971
1972 static int hub_port_debounce(struct usb_hub *hub, int port1)
1973 {
1974 int ret;
1975 int total_time, stable_time = 0;
1976 u16 portchange, portstatus;
1977 unsigned connection = 0xffff;
1978
1979 for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
1980 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1981 if (ret < 0)
1982 return ret;
1983
1984 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
1985 (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
1986 stable_time += HUB_DEBOUNCE_STEP;
1987 if (stable_time >= HUB_DEBOUNCE_STABLE)
1988 break;
1989 } else {
1990 stable_time = 0;
1991 connection = portstatus & USB_PORT_STAT_CONNECTION;
1992 }
1993
1994 if (portchange & USB_PORT_STAT_C_CONNECTION) {
1995 clear_port_feature(hub->hdev, port1,
1996 USB_PORT_FEAT_C_CONNECTION);
1997 }
1998
1999 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2000 break;
2001 msleep(HUB_DEBOUNCE_STEP);
2002 }
2003
2004 dev_dbg (hub->intfdev,
2005 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2006 port1, total_time, stable_time, portstatus);
2007
2008 if (stable_time < HUB_DEBOUNCE_STABLE)
2009 return -ETIMEDOUT;
2010 return portstatus;
2011 }
2012
2013 static void ep0_reinit(struct usb_device *udev)
2014 {
2015 usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2016 usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2017 udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2018 }
2019
2020 #define usb_sndaddr0pipe() (PIPE_CONTROL << 30)
2021 #define usb_rcvaddr0pipe() ((PIPE_CONTROL << 30) | USB_DIR_IN)
2022
2023 static int hub_set_address(struct usb_device *udev)
2024 {
2025 int retval;
2026
2027 if (udev->devnum == 0)
2028 return -EINVAL;
2029 if (udev->state == USB_STATE_ADDRESS)
2030 return 0;
2031 if (udev->state != USB_STATE_DEFAULT)
2032 return -EINVAL;
2033 retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2034 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2035 NULL, 0, USB_CTRL_SET_TIMEOUT);
2036 if (retval == 0) {
2037 usb_set_device_state(udev, USB_STATE_ADDRESS);
2038 ep0_reinit(udev);
2039 }
2040 return retval;
2041 }
2042
2043 /* Reset device, (re)assign address, get device descriptor.
2044 * Device connection must be stable, no more debouncing needed.
2045 * Returns device in USB_STATE_ADDRESS, except on error.
2046 *
2047 * If this is called for an already-existing device (as part of
2048 * usb_reset_device), the caller must own the device lock. For a
2049 * newly detected device that is not accessible through any global
2050 * pointers, it's not necessary to lock the device.
2051 */
2052 static int
2053 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2054 int retry_counter)
2055 {
2056 static DEFINE_MUTEX(usb_address0_mutex);
2057
2058 struct usb_device *hdev = hub->hdev;
2059 int i, j, retval;
2060 unsigned delay = HUB_SHORT_RESET_TIME;
2061 enum usb_device_speed oldspeed = udev->speed;
2062 char *speed, *type;
2063
2064 /* root hub ports have a slightly longer reset period
2065 * (from USB 2.0 spec, section 7.1.7.5)
2066 */
2067 if (!hdev->parent) {
2068 delay = HUB_ROOT_RESET_TIME;
2069 if (port1 == hdev->bus->otg_port)
2070 hdev->bus->b_hnp_enable = 0;
2071 }
2072
2073 /* Some low speed devices have problems with the quick delay, so */
2074 /* be a bit pessimistic with those devices. RHbug #23670 */
2075 if (oldspeed == USB_SPEED_LOW)
2076 delay = HUB_LONG_RESET_TIME;
2077
2078 mutex_lock(&usb_address0_mutex);
2079
2080 /* Reset the device; full speed may morph to high speed */
2081 retval = hub_port_reset(hub, port1, udev, delay);
2082 if (retval < 0) /* error or disconnect */
2083 goto fail;
2084 /* success, speed is known */
2085 retval = -ENODEV;
2086
2087 if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2088 dev_dbg(&udev->dev, "device reset changed speed!\n");
2089 goto fail;
2090 }
2091 oldspeed = udev->speed;
2092
2093 /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2094 * it's fixed size except for full speed devices.
2095 * For Wireless USB devices, ep0 max packet is always 512 (tho
2096 * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
2097 */
2098 switch (udev->speed) {
2099 case USB_SPEED_VARIABLE: /* fixed at 512 */
2100 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(512);
2101 break;
2102 case USB_SPEED_HIGH: /* fixed at 64 */
2103 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2104 break;
2105 case USB_SPEED_FULL: /* 8, 16, 32, or 64 */
2106 /* to determine the ep0 maxpacket size, try to read
2107 * the device descriptor to get bMaxPacketSize0 and
2108 * then correct our initial guess.
2109 */
2110 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2111 break;
2112 case USB_SPEED_LOW: /* fixed at 8 */
2113 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2114 break;
2115 default:
2116 goto fail;
2117 }
2118
2119 type = "";
2120 switch (udev->speed) {
2121 case USB_SPEED_LOW: speed = "low"; break;
2122 case USB_SPEED_FULL: speed = "full"; break;
2123 case USB_SPEED_HIGH: speed = "high"; break;
2124 case USB_SPEED_VARIABLE:
2125 speed = "variable";
2126 type = "Wireless ";
2127 break;
2128 default: speed = "?"; break;
2129 }
2130 dev_info (&udev->dev,
2131 "%s %s speed %sUSB device using %s and address %d\n",
2132 (udev->config) ? "reset" : "new", speed, type,
2133 udev->bus->controller->driver->name, udev->devnum);
2134
2135 /* Set up TT records, if needed */
2136 if (hdev->tt) {
2137 udev->tt = hdev->tt;
2138 udev->ttport = hdev->ttport;
2139 } else if (udev->speed != USB_SPEED_HIGH
2140 && hdev->speed == USB_SPEED_HIGH) {
2141 udev->tt = &hub->tt;
2142 udev->ttport = port1;
2143 }
2144
2145 /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2146 * Because device hardware and firmware is sometimes buggy in
2147 * this area, and this is how Linux has done it for ages.
2148 * Change it cautiously.
2149 *
2150 * NOTE: If USE_NEW_SCHEME() is true we will start by issuing
2151 * a 64-byte GET_DESCRIPTOR request. This is what Windows does,
2152 * so it may help with some non-standards-compliant devices.
2153 * Otherwise we start with SET_ADDRESS and then try to read the
2154 * first 8 bytes of the device descriptor to get the ep0 maxpacket
2155 * value.
2156 */
2157 for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2158 if (USE_NEW_SCHEME(retry_counter)) {
2159 struct usb_device_descriptor *buf;
2160 int r = 0;
2161
2162 #define GET_DESCRIPTOR_BUFSIZE 64
2163 buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2164 if (!buf) {
2165 retval = -ENOMEM;
2166 continue;
2167 }
2168
2169 /* Retry on all errors; some devices are flakey.
2170 * 255 is for WUSB devices, we actually need to use
2171 * 512 (WUSB1.0[4.8.1]).
2172 */
2173 for (j = 0; j < 3; ++j) {
2174 buf->bMaxPacketSize0 = 0;
2175 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2176 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2177 USB_DT_DEVICE << 8, 0,
2178 buf, GET_DESCRIPTOR_BUFSIZE,
2179 USB_CTRL_GET_TIMEOUT);
2180 switch (buf->bMaxPacketSize0) {
2181 case 8: case 16: case 32: case 64: case 255:
2182 if (buf->bDescriptorType ==
2183 USB_DT_DEVICE) {
2184 r = 0;
2185 break;
2186 }
2187 /* FALL THROUGH */
2188 default:
2189 if (r == 0)
2190 r = -EPROTO;
2191 break;
2192 }
2193 if (r == 0)
2194 break;
2195 }
2196 udev->descriptor.bMaxPacketSize0 =
2197 buf->bMaxPacketSize0;
2198 kfree(buf);
2199
2200 retval = hub_port_reset(hub, port1, udev, delay);
2201 if (retval < 0) /* error or disconnect */
2202 goto fail;
2203 if (oldspeed != udev->speed) {
2204 dev_dbg(&udev->dev,
2205 "device reset changed speed!\n");
2206 retval = -ENODEV;
2207 goto fail;
2208 }
2209 if (r) {
2210 dev_err(&udev->dev, "device descriptor "
2211 "read/%s, error %d\n",
2212 "64", r);
2213 retval = -EMSGSIZE;
2214 continue;
2215 }
2216 #undef GET_DESCRIPTOR_BUFSIZE
2217 }
2218
2219 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2220 retval = hub_set_address(udev);
2221 if (retval >= 0)
2222 break;
2223 msleep(200);
2224 }
2225 if (retval < 0) {
2226 dev_err(&udev->dev,
2227 "device not accepting address %d, error %d\n",
2228 udev->devnum, retval);
2229 goto fail;
2230 }
2231
2232 /* cope with hardware quirkiness:
2233 * - let SET_ADDRESS settle, some device hardware wants it
2234 * - read ep0 maxpacket even for high and low speed,
2235 */
2236 msleep(10);
2237 if (USE_NEW_SCHEME(retry_counter))
2238 break;
2239
2240 retval = usb_get_device_descriptor(udev, 8);
2241 if (retval < 8) {
2242 dev_err(&udev->dev, "device descriptor "
2243 "read/%s, error %d\n",
2244 "8", retval);
2245 if (retval >= 0)
2246 retval = -EMSGSIZE;
2247 } else {
2248 retval = 0;
2249 break;
2250 }
2251 }
2252 if (retval)
2253 goto fail;
2254
2255 i = udev->descriptor.bMaxPacketSize0 == 0xff?
2256 512 : udev->descriptor.bMaxPacketSize0;
2257 if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2258 if (udev->speed != USB_SPEED_FULL ||
2259 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2260 dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2261 retval = -EMSGSIZE;
2262 goto fail;
2263 }
2264 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2265 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2266 ep0_reinit(udev);
2267 }
2268
2269 retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2270 if (retval < (signed)sizeof(udev->descriptor)) {
2271 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2272 "all", retval);
2273 if (retval >= 0)
2274 retval = -ENOMSG;
2275 goto fail;
2276 }
2277
2278 retval = 0;
2279
2280 fail:
2281 if (retval)
2282 hub_port_disable(hub, port1, 0);
2283 mutex_unlock(&usb_address0_mutex);
2284 return retval;
2285 }
2286
2287 static void
2288 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2289 {
2290 struct usb_qualifier_descriptor *qual;
2291 int status;
2292
2293 qual = kmalloc (sizeof *qual, GFP_KERNEL);
2294 if (qual == NULL)
2295 return;
2296
2297 status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2298 qual, sizeof *qual);
2299 if (status == sizeof *qual) {
2300 dev_info(&udev->dev, "not running at top speed; "
2301 "connect to a high speed hub\n");
2302 /* hub LEDs are probably harder to miss than syslog */
2303 if (hub->has_indicators) {
2304 hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2305 schedule_delayed_work (&hub->leds, 0);
2306 }
2307 }
2308 kfree(qual);
2309 }
2310
2311 static unsigned
2312 hub_power_remaining (struct usb_hub *hub)
2313 {
2314 struct usb_device *hdev = hub->hdev;
2315 int remaining;
2316 int port1;
2317
2318 if (!hub->limited_power)
2319 return 0;
2320
2321 remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
2322 for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
2323 struct usb_device *udev = hdev->children[port1 - 1];
2324 int delta;
2325
2326 if (!udev)
2327 continue;
2328
2329 /* Unconfigured devices may not use more than 100mA,
2330 * or 8mA for OTG ports */
2331 if (udev->actconfig)
2332 delta = udev->actconfig->desc.bMaxPower * 2;
2333 else if (port1 != udev->bus->otg_port || hdev->parent)
2334 delta = 100;
2335 else
2336 delta = 8;
2337 if (delta > hub->mA_per_port)
2338 dev_warn(&udev->dev, "%dmA is over %umA budget "
2339 "for port %d!\n",
2340 delta, hub->mA_per_port, port1);
2341 remaining -= delta;
2342 }
2343 if (remaining < 0) {
2344 dev_warn(hub->intfdev, "%dmA over power budget!\n",
2345 - remaining);
2346 remaining = 0;
2347 }
2348 return remaining;
2349 }
2350
2351 /* Handle physical or logical connection change events.
2352 * This routine is called when:
2353 * a port connection-change occurs;
2354 * a port enable-change occurs (often caused by EMI);
2355 * usb_reset_device() encounters changed descriptors (as from
2356 * a firmware download)
2357 * caller already locked the hub
2358 */
2359 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2360 u16 portstatus, u16 portchange)
2361 {
2362 struct usb_device *hdev = hub->hdev;
2363 struct device *hub_dev = hub->intfdev;
2364 u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2365 int status, i;
2366
2367 dev_dbg (hub_dev,
2368 "port %d, status %04x, change %04x, %s\n",
2369 port1, portstatus, portchange, portspeed (portstatus));
2370
2371 if (hub->has_indicators) {
2372 set_port_led(hub, port1, HUB_LED_AUTO);
2373 hub->indicator[port1-1] = INDICATOR_AUTO;
2374 }
2375
2376 /* Disconnect any existing devices under this port */
2377 if (hdev->children[port1-1])
2378 usb_disconnect(&hdev->children[port1-1]);
2379 clear_bit(port1, hub->change_bits);
2380
2381 #ifdef CONFIG_USB_OTG
2382 /* during HNP, don't repeat the debounce */
2383 if (hdev->bus->is_b_host)
2384 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2385 #endif
2386
2387 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2388 status = hub_port_debounce(hub, port1);
2389 if (status < 0) {
2390 if (printk_ratelimit())
2391 dev_err (hub_dev, "connect-debounce failed, "
2392 "port %d disabled\n", port1);
2393 goto done;
2394 }
2395 portstatus = status;
2396 }
2397
2398 /* Return now if nothing is connected */
2399 if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2400
2401 /* maybe switch power back on (e.g. root hub was reset) */
2402 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
2403 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2404 set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2405
2406 if (portstatus & USB_PORT_STAT_ENABLE)
2407 goto done;
2408 return;
2409 }
2410
2411 for (i = 0; i < SET_CONFIG_TRIES; i++) {
2412 struct usb_device *udev;
2413
2414 /* reallocate for each attempt, since references
2415 * to the previous one can escape in various ways
2416 */
2417 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2418 if (!udev) {
2419 dev_err (hub_dev,
2420 "couldn't allocate port %d usb_device\n",
2421 port1);
2422 goto done;
2423 }
2424
2425 usb_set_device_state(udev, USB_STATE_POWERED);
2426 udev->speed = USB_SPEED_UNKNOWN;
2427 udev->bus_mA = hub->mA_per_port;
2428 udev->level = hdev->level + 1;
2429
2430 /* set the address */
2431 choose_address(udev);
2432 if (udev->devnum <= 0) {
2433 status = -ENOTCONN; /* Don't retry */
2434 goto loop;
2435 }
2436
2437 /* reset and get descriptor */
2438 status = hub_port_init(hub, udev, port1, i);
2439 if (status < 0)
2440 goto loop;
2441
2442 /* consecutive bus-powered hubs aren't reliable; they can
2443 * violate the voltage drop budget. if the new child has
2444 * a "powered" LED, users should notice we didn't enable it
2445 * (without reading syslog), even without per-port LEDs
2446 * on the parent.
2447 */
2448 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2449 && udev->bus_mA <= 100) {
2450 u16 devstat;
2451
2452 status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2453 &devstat);
2454 if (status < 2) {
2455 dev_dbg(&udev->dev, "get status %d ?\n", status);
2456 goto loop_disable;
2457 }
2458 le16_to_cpus(&devstat);
2459 if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2460 dev_err(&udev->dev,
2461 "can't connect bus-powered hub "
2462 "to this port\n");
2463 if (hub->has_indicators) {
2464 hub->indicator[port1-1] =
2465 INDICATOR_AMBER_BLINK;
2466 schedule_delayed_work (&hub->leds, 0);
2467 }
2468 status = -ENOTCONN; /* Don't retry */
2469 goto loop_disable;
2470 }
2471 }
2472
2473 /* check for devices running slower than they could */
2474 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2475 && udev->speed == USB_SPEED_FULL
2476 && highspeed_hubs != 0)
2477 check_highspeed (hub, udev, port1);
2478
2479 /* Store the parent's children[] pointer. At this point
2480 * udev becomes globally accessible, although presumably
2481 * no one will look at it until hdev is unlocked.
2482 */
2483 status = 0;
2484
2485 /* We mustn't add new devices if the parent hub has
2486 * been disconnected; we would race with the
2487 * recursively_mark_NOTATTACHED() routine.
2488 */
2489 spin_lock_irq(&device_state_lock);
2490 if (hdev->state == USB_STATE_NOTATTACHED)
2491 status = -ENOTCONN;
2492 else
2493 hdev->children[port1-1] = udev;
2494 spin_unlock_irq(&device_state_lock);
2495
2496 /* Run it through the hoops (find a driver, etc) */
2497 if (!status) {
2498 status = usb_new_device(udev);
2499 if (status) {
2500 spin_lock_irq(&device_state_lock);
2501 hdev->children[port1-1] = NULL;
2502 spin_unlock_irq(&device_state_lock);
2503 }
2504 }
2505
2506 if (status)
2507 goto loop_disable;
2508
2509 status = hub_power_remaining(hub);
2510 if (status)
2511 dev_dbg(hub_dev, "%dmA power budget left\n", status);
2512
2513 return;
2514
2515 loop_disable:
2516 hub_port_disable(hub, port1, 1);
2517 loop:
2518 ep0_reinit(udev);
2519 release_address(udev);
2520 usb_put_dev(udev);
2521 if ((status == -ENOTCONN) || (status == -ENOTSUPP))
2522 break;
2523 }
2524
2525 done:
2526 hub_port_disable(hub, port1, 1);
2527 }
2528
2529 static void hub_events(void)
2530 {
2531 struct list_head *tmp;
2532 struct usb_device *hdev;
2533 struct usb_interface *intf;
2534 struct usb_hub *hub;
2535 struct device *hub_dev;
2536 u16 hubstatus;
2537 u16 hubchange;
2538 u16 portstatus;
2539 u16 portchange;
2540 int i, ret;
2541 int connect_change;
2542
2543 /*
2544 * We restart the list every time to avoid a deadlock with
2545 * deleting hubs downstream from this one. This should be
2546 * safe since we delete the hub from the event list.
2547 * Not the most efficient, but avoids deadlocks.
2548 */
2549 while (1) {
2550
2551 /* Grab the first entry at the beginning of the list */
2552 spin_lock_irq(&hub_event_lock);
2553 if (list_empty(&hub_event_list)) {
2554 spin_unlock_irq(&hub_event_lock);
2555 break;
2556 }
2557
2558 tmp = hub_event_list.next;
2559 list_del_init(tmp);
2560
2561 hub = list_entry(tmp, struct usb_hub, event_list);
2562 kref_get(&hub->kref);
2563 spin_unlock_irq(&hub_event_lock);
2564
2565 hdev = hub->hdev;
2566 hub_dev = hub->intfdev;
2567 intf = to_usb_interface(hub_dev);
2568 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
2569 hdev->state, hub->descriptor
2570 ? hub->descriptor->bNbrPorts
2571 : 0,
2572 /* NOTE: expects max 15 ports... */
2573 (u16) hub->change_bits[0],
2574 (u16) hub->event_bits[0]);
2575
2576 /* Lock the device, then check to see if we were
2577 * disconnected while waiting for the lock to succeed. */
2578 usb_lock_device(hdev);
2579 if (unlikely(hub->disconnected))
2580 goto loop;
2581
2582 /* If the hub has died, clean up after it */
2583 if (hdev->state == USB_STATE_NOTATTACHED) {
2584 hub->error = -ENODEV;
2585 hub_pre_reset(intf);
2586 goto loop;
2587 }
2588
2589 /* Autoresume */
2590 ret = usb_autopm_get_interface(intf);
2591 if (ret) {
2592 dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
2593 goto loop;
2594 }
2595
2596 /* If this is an inactive hub, do nothing */
2597 if (hub->quiescing)
2598 goto loop_autopm;
2599
2600 if (hub->error) {
2601 dev_dbg (hub_dev, "resetting for error %d\n",
2602 hub->error);
2603
2604 ret = usb_reset_composite_device(hdev, intf);
2605 if (ret) {
2606 dev_dbg (hub_dev,
2607 "error resetting hub: %d\n", ret);
2608 goto loop_autopm;
2609 }
2610
2611 hub->nerrors = 0;
2612 hub->error = 0;
2613 }
2614
2615 /* deal with port status changes */
2616 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2617 if (test_bit(i, hub->busy_bits))
2618 continue;
2619 connect_change = test_bit(i, hub->change_bits);
2620 if (!test_and_clear_bit(i, hub->event_bits) &&
2621 !connect_change && !hub->activating)
2622 continue;
2623
2624 ret = hub_port_status(hub, i,
2625 &portstatus, &portchange);
2626 if (ret < 0)
2627 continue;
2628
2629 if (hub->activating && !hdev->children[i-1] &&
2630 (portstatus &
2631 USB_PORT_STAT_CONNECTION))
2632 connect_change = 1;
2633
2634 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2635 clear_port_feature(hdev, i,
2636 USB_PORT_FEAT_C_CONNECTION);
2637 connect_change = 1;
2638 }
2639
2640 if (portchange & USB_PORT_STAT_C_ENABLE) {
2641 if (!connect_change)
2642 dev_dbg (hub_dev,
2643 "port %d enable change, "
2644 "status %08x\n",
2645 i, portstatus);
2646 clear_port_feature(hdev, i,
2647 USB_PORT_FEAT_C_ENABLE);
2648
2649 /*
2650 * EM interference sometimes causes badly
2651 * shielded USB devices to be shutdown by
2652 * the hub, this hack enables them again.
2653 * Works at least with mouse driver.
2654 */
2655 if (!(portstatus & USB_PORT_STAT_ENABLE)
2656 && !connect_change
2657 && hdev->children[i-1]) {
2658 dev_err (hub_dev,
2659 "port %i "
2660 "disabled by hub (EMI?), "
2661 "re-enabling...\n",
2662 i);
2663 connect_change = 1;
2664 }
2665 }
2666
2667 if (portchange & USB_PORT_STAT_C_SUSPEND) {
2668 clear_port_feature(hdev, i,
2669 USB_PORT_FEAT_C_SUSPEND);
2670 if (hdev->children[i-1]) {
2671 ret = remote_wakeup(hdev->
2672 children[i-1]);
2673 if (ret < 0)
2674 connect_change = 1;
2675 } else {
2676 ret = -ENODEV;
2677 hub_port_disable(hub, i, 1);
2678 }
2679 dev_dbg (hub_dev,
2680 "resume on port %d, status %d\n",
2681 i, ret);
2682 }
2683
2684 if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2685 dev_err (hub_dev,
2686 "over-current change on port %d\n",
2687 i);
2688 clear_port_feature(hdev, i,
2689 USB_PORT_FEAT_C_OVER_CURRENT);
2690 hub_power_on(hub);
2691 }
2692
2693 if (portchange & USB_PORT_STAT_C_RESET) {
2694 dev_dbg (hub_dev,
2695 "reset change on port %d\n",
2696 i);
2697 clear_port_feature(hdev, i,
2698 USB_PORT_FEAT_C_RESET);
2699 }
2700
2701 if (connect_change)
2702 hub_port_connect_change(hub, i,
2703 portstatus, portchange);
2704 } /* end for i */
2705
2706 /* deal with hub status changes */
2707 if (test_and_clear_bit(0, hub->event_bits) == 0)
2708 ; /* do nothing */
2709 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2710 dev_err (hub_dev, "get_hub_status failed\n");
2711 else {
2712 if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2713 dev_dbg (hub_dev, "power change\n");
2714 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2715 if (hubstatus & HUB_STATUS_LOCAL_POWER)
2716 /* FIXME: Is this always true? */
2717 hub->limited_power = 0;
2718 else
2719 hub->limited_power = 1;
2720 }
2721 if (hubchange & HUB_CHANGE_OVERCURRENT) {
2722 dev_dbg (hub_dev, "overcurrent change\n");
2723 msleep(500); /* Cool down */
2724 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2725 hub_power_on(hub);
2726 }
2727 }
2728
2729 hub->activating = 0;
2730
2731 /* If this is a root hub, tell the HCD it's okay to
2732 * re-enable port-change interrupts now. */
2733 if (!hdev->parent && !hub->busy_bits[0])
2734 usb_enable_root_hub_irq(hdev->bus);
2735
2736 loop_autopm:
2737 /* Allow autosuspend if we're not going to run again */
2738 if (list_empty(&hub->event_list))
2739 usb_autopm_enable(intf);
2740 loop:
2741 usb_unlock_device(hdev);
2742 kref_put(&hub->kref, hub_release);
2743
2744 } /* end while (1) */
2745 }
2746
2747 static int hub_thread(void *__unused)
2748 {
2749 do {
2750 hub_events();
2751 wait_event_interruptible(khubd_wait,
2752 !list_empty(&hub_event_list) ||
2753 kthread_should_stop());
2754 try_to_freeze();
2755 } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2756
2757 pr_debug("%s: khubd exiting\n", usbcore_name);
2758 return 0;
2759 }
2760
2761 static struct usb_device_id hub_id_table [] = {
2762 { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2763 .bDeviceClass = USB_CLASS_HUB},
2764 { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2765 .bInterfaceClass = USB_CLASS_HUB},
2766 { } /* Terminating entry */
2767 };
2768
2769 MODULE_DEVICE_TABLE (usb, hub_id_table);
2770
2771 static struct usb_driver hub_driver = {
2772 .name = "hub",
2773 .probe = hub_probe,
2774 .disconnect = hub_disconnect,
2775 .suspend = hub_suspend,
2776 .resume = hub_resume,
2777 .reset_resume = hub_reset_resume,
2778 .pre_reset = hub_pre_reset,
2779 .post_reset = hub_post_reset,
2780 .ioctl = hub_ioctl,
2781 .id_table = hub_id_table,
2782 .supports_autosuspend = 1,
2783 };
2784
2785 int usb_hub_init(void)
2786 {
2787 if (usb_register(&hub_driver) < 0) {
2788 printk(KERN_ERR "%s: can't register hub driver\n",
2789 usbcore_name);
2790 return -1;
2791 }
2792
2793 khubd_task = kthread_run(hub_thread, NULL, "khubd");
2794 if (!IS_ERR(khubd_task))
2795 return 0;
2796
2797 /* Fall through if kernel_thread failed */
2798 usb_deregister(&hub_driver);
2799 printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2800
2801 return -1;
2802 }
2803
2804 void usb_hub_cleanup(void)
2805 {
2806 kthread_stop(khubd_task);
2807
2808 /*
2809 * Hub resources are freed for us by usb_deregister. It calls
2810 * usb_driver_purge on every device which in turn calls that
2811 * devices disconnect function if it is using this driver.
2812 * The hub_disconnect function takes care of releasing the
2813 * individual hub resources. -greg
2814 */
2815 usb_deregister(&hub_driver);
2816 } /* usb_hub_cleanup() */
2817
2818 static int config_descriptors_changed(struct usb_device *udev)
2819 {
2820 unsigned index;
2821 unsigned len = 0;
2822 struct usb_config_descriptor *buf;
2823
2824 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2825 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2826 len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2827 }
2828 buf = kmalloc (len, GFP_KERNEL);
2829 if (buf == NULL) {
2830 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2831 /* assume the worst */
2832 return 1;
2833 }
2834 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2835 int length;
2836 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2837
2838 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2839 old_length);
2840 if (length < old_length) {
2841 dev_dbg(&udev->dev, "config index %d, error %d\n",
2842 index, length);
2843 break;
2844 }
2845 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2846 != 0) {
2847 dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2848 index, buf->bConfigurationValue);
2849 break;
2850 }
2851 }
2852 kfree(buf);
2853 return index != udev->descriptor.bNumConfigurations;
2854 }
2855
2856 /**
2857 * usb_reset_device - perform a USB port reset to reinitialize a device
2858 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2859 *
2860 * WARNING - don't use this routine to reset a composite device
2861 * (one with multiple interfaces owned by separate drivers)!
2862 * Use usb_reset_composite_device() instead.
2863 *
2864 * Do a port reset, reassign the device's address, and establish its
2865 * former operating configuration. If the reset fails, or the device's
2866 * descriptors change from their values before the reset, or the original
2867 * configuration and altsettings cannot be restored, a flag will be set
2868 * telling khubd to pretend the device has been disconnected and then
2869 * re-connected. All drivers will be unbound, and the device will be
2870 * re-enumerated and probed all over again.
2871 *
2872 * Returns 0 if the reset succeeded, -ENODEV if the device has been
2873 * flagged for logical disconnection, or some other negative error code
2874 * if the reset wasn't even attempted.
2875 *
2876 * The caller must own the device lock. For example, it's safe to use
2877 * this from a driver probe() routine after downloading new firmware.
2878 * For calls that might not occur during probe(), drivers should lock
2879 * the device using usb_lock_device_for_reset().
2880 *
2881 * Locking exception: This routine may also be called from within an
2882 * autoresume handler. Such usage won't conflict with other tasks
2883 * holding the device lock because these tasks should always call
2884 * usb_autopm_resume_device(), thereby preventing any unwanted autoresume.
2885 */
2886 int usb_reset_device(struct usb_device *udev)
2887 {
2888 struct usb_device *parent_hdev = udev->parent;
2889 struct usb_hub *parent_hub;
2890 struct usb_device_descriptor descriptor = udev->descriptor;
2891 int i, ret = 0;
2892 int port1 = udev->portnum;
2893
2894 if (udev->state == USB_STATE_NOTATTACHED ||
2895 udev->state == USB_STATE_SUSPENDED) {
2896 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2897 udev->state);
2898 return -EINVAL;
2899 }
2900
2901 if (!parent_hdev) {
2902 /* this requires hcd-specific logic; see OHCI hc_restart() */
2903 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2904 return -EISDIR;
2905 }
2906 parent_hub = hdev_to_hub(parent_hdev);
2907
2908 set_bit(port1, parent_hub->busy_bits);
2909 for (i = 0; i < SET_CONFIG_TRIES; ++i) {
2910
2911 /* ep0 maxpacket size may change; let the HCD know about it.
2912 * Other endpoints will be handled by re-enumeration. */
2913 ep0_reinit(udev);
2914 ret = hub_port_init(parent_hub, udev, port1, i);
2915 if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
2916 break;
2917 }
2918 clear_bit(port1, parent_hub->busy_bits);
2919 if (!parent_hdev->parent && !parent_hub->busy_bits[0])
2920 usb_enable_root_hub_irq(parent_hdev->bus);
2921
2922 if (ret < 0)
2923 goto re_enumerate;
2924
2925 /* Device might have changed firmware (DFU or similar) */
2926 if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
2927 || config_descriptors_changed (udev)) {
2928 dev_info(&udev->dev, "device firmware changed\n");
2929 udev->descriptor = descriptor; /* for disconnect() calls */
2930 goto re_enumerate;
2931 }
2932
2933 if (!udev->actconfig)
2934 goto done;
2935
2936 ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2937 USB_REQ_SET_CONFIGURATION, 0,
2938 udev->actconfig->desc.bConfigurationValue, 0,
2939 NULL, 0, USB_CTRL_SET_TIMEOUT);
2940 if (ret < 0) {
2941 dev_err(&udev->dev,
2942 "can't restore configuration #%d (error=%d)\n",
2943 udev->actconfig->desc.bConfigurationValue, ret);
2944 goto re_enumerate;
2945 }
2946 usb_set_device_state(udev, USB_STATE_CONFIGURED);
2947
2948 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
2949 struct usb_interface *intf = udev->actconfig->interface[i];
2950 struct usb_interface_descriptor *desc;
2951
2952 /* set_interface resets host side toggle even
2953 * for altsetting zero. the interface may have no driver.
2954 */
2955 desc = &intf->cur_altsetting->desc;
2956 ret = usb_set_interface(udev, desc->bInterfaceNumber,
2957 desc->bAlternateSetting);
2958 if (ret < 0) {
2959 dev_err(&udev->dev, "failed to restore interface %d "
2960 "altsetting %d (error=%d)\n",
2961 desc->bInterfaceNumber,
2962 desc->bAlternateSetting,
2963 ret);
2964 goto re_enumerate;
2965 }
2966 }
2967
2968 done:
2969 return 0;
2970
2971 re_enumerate:
2972 hub_port_logical_disconnect(parent_hub, port1);
2973 return -ENODEV;
2974 }
2975 EXPORT_SYMBOL(usb_reset_device);
2976
2977 /**
2978 * usb_reset_composite_device - warn interface drivers and perform a USB port reset
2979 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2980 * @iface: interface bound to the driver making the request (optional)
2981 *
2982 * Warns all drivers bound to registered interfaces (using their pre_reset
2983 * method), performs the port reset, and then lets the drivers know that
2984 * the reset is over (using their post_reset method).
2985 *
2986 * Return value is the same as for usb_reset_device().
2987 *
2988 * The caller must own the device lock. For example, it's safe to use
2989 * this from a driver probe() routine after downloading new firmware.
2990 * For calls that might not occur during probe(), drivers should lock
2991 * the device using usb_lock_device_for_reset().
2992 *
2993 * The interface locks are acquired during the pre_reset stage and released
2994 * during the post_reset stage. However if iface is not NULL and is
2995 * currently being probed, we assume that the caller already owns its
2996 * lock.
2997 */
2998 int usb_reset_composite_device(struct usb_device *udev,
2999 struct usb_interface *iface)
3000 {
3001 int ret;
3002 struct usb_host_config *config = udev->actconfig;
3003
3004 if (udev->state == USB_STATE_NOTATTACHED ||
3005 udev->state == USB_STATE_SUSPENDED) {
3006 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3007 udev->state);
3008 return -EINVAL;
3009 }
3010
3011 /* Prevent autosuspend during the reset */
3012 usb_autoresume_device(udev);
3013
3014 if (iface && iface->condition != USB_INTERFACE_BINDING)
3015 iface = NULL;
3016
3017 if (config) {
3018 int i;
3019 struct usb_interface *cintf;
3020 struct usb_driver *drv;
3021
3022 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
3023 cintf = config->interface[i];
3024 if (cintf != iface)
3025 down(&cintf->dev.sem);
3026 if (device_is_registered(&cintf->dev) &&
3027 cintf->dev.driver) {
3028 drv = to_usb_driver(cintf->dev.driver);
3029 if (drv->pre_reset)
3030 (drv->pre_reset)(cintf);
3031 /* FIXME: Unbind if pre_reset returns an error or isn't defined */
3032 }
3033 }
3034 }
3035
3036 ret = usb_reset_device(udev);
3037
3038 if (config) {
3039 int i;
3040 struct usb_interface *cintf;
3041 struct usb_driver *drv;
3042
3043 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
3044 cintf = config->interface[i];
3045 if (device_is_registered(&cintf->dev) &&
3046 cintf->dev.driver) {
3047 drv = to_usb_driver(cintf->dev.driver);
3048 if (drv->post_reset)
3049 (drv->post_reset)(cintf);
3050 /* FIXME: Unbind if post_reset returns an error or isn't defined */
3051 }
3052 if (cintf != iface)
3053 up(&cintf->dev.sem);
3054 }
3055 }
3056
3057 usb_autosuspend_device(udev);
3058 return ret;
3059 }
3060 EXPORT_SYMBOL(usb_reset_composite_device);
WandBoard kernel