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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/usb/core/hub.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/usb/core/hub.c')
-rw-r--r--drivers/usb/core/hub.c3057
1 files changed, 3057 insertions, 0 deletions
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
new file mode 100644
index 000000000000..fa0dc4f6de47
--- /dev/null
+++ b/drivers/usb/core/hub.c
@@ -0,0 +1,3057 @@
1/*
2 * USB hub driver.
3 *
4 * (C) Copyright 1999 Linus Torvalds
5 * (C) Copyright 1999 Johannes Erdfelt
6 * (C) Copyright 1999 Gregory P. Smith
7 * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
8 *
9 */
10
11#include <linux/config.h>
12#ifdef CONFIG_USB_DEBUG
13 #define DEBUG
14#else
15 #undef DEBUG
16#endif
17#include <linux/kernel.h>
18#include <linux/errno.h>
19#include <linux/module.h>
20#include <linux/moduleparam.h>
21#include <linux/completion.h>
22#include <linux/sched.h>
23#include <linux/list.h>
24#include <linux/slab.h>
25#include <linux/smp_lock.h>
26#include <linux/ioctl.h>
27#include <linux/usb.h>
28#include <linux/usbdevice_fs.h>
29
30#include <asm/semaphore.h>
31#include <asm/uaccess.h>
32#include <asm/byteorder.h>
33
34#include "usb.h"
35#include "hcd.h"
36#include "hub.h"
37
38/* Protect struct usb_device->state and ->children members
39 * Note: Both are also protected by ->serialize, except that ->state can
40 * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
41static DEFINE_SPINLOCK(device_state_lock);
42
43/* khubd's worklist and its lock */
44static DEFINE_SPINLOCK(hub_event_lock);
45static LIST_HEAD(hub_event_list); /* List of hubs needing servicing */
46
47/* Wakes up khubd */
48static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
49
50static pid_t khubd_pid = 0; /* PID of khubd */
51static DECLARE_COMPLETION(khubd_exited);
52
53/* cycle leds on hubs that aren't blinking for attention */
54static int blinkenlights = 0;
55module_param (blinkenlights, bool, S_IRUGO);
56MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
57
58/*
59 * As of 2.6.10 we introduce a new USB device initialization scheme which
60 * closely resembles the way Windows works. Hopefully it will be compatible
61 * with a wider range of devices than the old scheme. However some previously
62 * working devices may start giving rise to "device not accepting address"
63 * errors; if that happens the user can try the old scheme by adjusting the
64 * following module parameters.
65 *
66 * For maximum flexibility there are two boolean parameters to control the
67 * hub driver's behavior. On the first initialization attempt, if the
68 * "old_scheme_first" parameter is set then the old scheme will be used,
69 * otherwise the new scheme is used. If that fails and "use_both_schemes"
70 * is set, then the driver will make another attempt, using the other scheme.
71 */
72static int old_scheme_first = 0;
73module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
74MODULE_PARM_DESC(old_scheme_first,
75 "start with the old device initialization scheme");
76
77static int use_both_schemes = 1;
78module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
79MODULE_PARM_DESC(use_both_schemes,
80 "try the other device initialization scheme if the "
81 "first one fails");
82
83
84#ifdef DEBUG
85static inline char *portspeed (int portstatus)
86{
87 if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
88 return "480 Mb/s";
89 else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
90 return "1.5 Mb/s";
91 else
92 return "12 Mb/s";
93}
94#endif
95
96/* Note that hdev or one of its children must be locked! */
97static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
98{
99 return usb_get_intfdata(hdev->actconfig->interface[0]);
100}
101
102/* USB 2.0 spec Section 11.24.4.5 */
103static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
104{
105 int i, ret;
106
107 for (i = 0; i < 3; i++) {
108 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
109 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
110 USB_DT_HUB << 8, 0, data, size,
111 USB_CTRL_GET_TIMEOUT);
112 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
113 return ret;
114 }
115 return -EINVAL;
116}
117
118/*
119 * USB 2.0 spec Section 11.24.2.1
120 */
121static int clear_hub_feature(struct usb_device *hdev, int feature)
122{
123 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
124 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
125}
126
127/*
128 * USB 2.0 spec Section 11.24.2.2
129 */
130static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
131{
132 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
133 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
134 NULL, 0, 1000);
135}
136
137/*
138 * USB 2.0 spec Section 11.24.2.13
139 */
140static int set_port_feature(struct usb_device *hdev, int port1, int feature)
141{
142 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
143 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
144 NULL, 0, 1000);
145}
146
147/*
148 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
149 * for info about using port indicators
150 */
151static void set_port_led(
152 struct usb_hub *hub,
153 int port1,
154 int selector
155)
156{
157 int status = set_port_feature(hub->hdev, (selector << 8) | port1,
158 USB_PORT_FEAT_INDICATOR);
159 if (status < 0)
160 dev_dbg (hub->intfdev,
161 "port %d indicator %s status %d\n",
162 port1,
163 ({ char *s; switch (selector) {
164 case HUB_LED_AMBER: s = "amber"; break;
165 case HUB_LED_GREEN: s = "green"; break;
166 case HUB_LED_OFF: s = "off"; break;
167 case HUB_LED_AUTO: s = "auto"; break;
168 default: s = "??"; break;
169 }; s; }),
170 status);
171}
172
173#define LED_CYCLE_PERIOD ((2*HZ)/3)
174
175static void led_work (void *__hub)
176{
177 struct usb_hub *hub = __hub;
178 struct usb_device *hdev = hub->hdev;
179 unsigned i;
180 unsigned changed = 0;
181 int cursor = -1;
182
183 if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
184 return;
185
186 for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
187 unsigned selector, mode;
188
189 /* 30%-50% duty cycle */
190
191 switch (hub->indicator[i]) {
192 /* cycle marker */
193 case INDICATOR_CYCLE:
194 cursor = i;
195 selector = HUB_LED_AUTO;
196 mode = INDICATOR_AUTO;
197 break;
198 /* blinking green = sw attention */
199 case INDICATOR_GREEN_BLINK:
200 selector = HUB_LED_GREEN;
201 mode = INDICATOR_GREEN_BLINK_OFF;
202 break;
203 case INDICATOR_GREEN_BLINK_OFF:
204 selector = HUB_LED_OFF;
205 mode = INDICATOR_GREEN_BLINK;
206 break;
207 /* blinking amber = hw attention */
208 case INDICATOR_AMBER_BLINK:
209 selector = HUB_LED_AMBER;
210 mode = INDICATOR_AMBER_BLINK_OFF;
211 break;
212 case INDICATOR_AMBER_BLINK_OFF:
213 selector = HUB_LED_OFF;
214 mode = INDICATOR_AMBER_BLINK;
215 break;
216 /* blink green/amber = reserved */
217 case INDICATOR_ALT_BLINK:
218 selector = HUB_LED_GREEN;
219 mode = INDICATOR_ALT_BLINK_OFF;
220 break;
221 case INDICATOR_ALT_BLINK_OFF:
222 selector = HUB_LED_AMBER;
223 mode = INDICATOR_ALT_BLINK;
224 break;
225 default:
226 continue;
227 }
228 if (selector != HUB_LED_AUTO)
229 changed = 1;
230 set_port_led(hub, i + 1, selector);
231 hub->indicator[i] = mode;
232 }
233 if (!changed && blinkenlights) {
234 cursor++;
235 cursor %= hub->descriptor->bNbrPorts;
236 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
237 hub->indicator[cursor] = INDICATOR_CYCLE;
238 changed++;
239 }
240 if (changed)
241 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
242}
243
244/* use a short timeout for hub/port status fetches */
245#define USB_STS_TIMEOUT 1000
246#define USB_STS_RETRIES 5
247
248/*
249 * USB 2.0 spec Section 11.24.2.6
250 */
251static int get_hub_status(struct usb_device *hdev,
252 struct usb_hub_status *data)
253{
254 int i, status = -ETIMEDOUT;
255
256 for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
257 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
258 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
259 data, sizeof(*data), USB_STS_TIMEOUT);
260 }
261 return status;
262}
263
264/*
265 * USB 2.0 spec Section 11.24.2.7
266 */
267static int get_port_status(struct usb_device *hdev, int port1,
268 struct usb_port_status *data)
269{
270 int i, status = -ETIMEDOUT;
271
272 for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
273 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
274 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
275 data, sizeof(*data), USB_STS_TIMEOUT);
276 }
277 return status;
278}
279
280static void kick_khubd(struct usb_hub *hub)
281{
282 unsigned long flags;
283
284 spin_lock_irqsave(&hub_event_lock, flags);
285 if (list_empty(&hub->event_list)) {
286 list_add_tail(&hub->event_list, &hub_event_list);
287 wake_up(&khubd_wait);
288 }
289 spin_unlock_irqrestore(&hub_event_lock, flags);
290}
291
292void usb_kick_khubd(struct usb_device *hdev)
293{
294 kick_khubd(hdev_to_hub(hdev));
295}
296
297
298/* completion function, fires on port status changes and various faults */
299static void hub_irq(struct urb *urb, struct pt_regs *regs)
300{
301 struct usb_hub *hub = (struct usb_hub *)urb->context;
302 int status;
303 int i;
304 unsigned long bits;
305
306 switch (urb->status) {
307 case -ENOENT: /* synchronous unlink */
308 case -ECONNRESET: /* async unlink */
309 case -ESHUTDOWN: /* hardware going away */
310 return;
311
312 default: /* presumably an error */
313 /* Cause a hub reset after 10 consecutive errors */
314 dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
315 if ((++hub->nerrors < 10) || hub->error)
316 goto resubmit;
317 hub->error = urb->status;
318 /* FALL THROUGH */
319
320 /* let khubd handle things */
321 case 0: /* we got data: port status changed */
322 bits = 0;
323 for (i = 0; i < urb->actual_length; ++i)
324 bits |= ((unsigned long) ((*hub->buffer)[i]))
325 << (i*8);
326 hub->event_bits[0] = bits;
327 break;
328 }
329
330 hub->nerrors = 0;
331
332 /* Something happened, let khubd figure it out */
333 kick_khubd(hub);
334
335resubmit:
336 if (hub->quiescing)
337 return;
338
339 if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
340 && status != -ENODEV && status != -EPERM)
341 dev_err (hub->intfdev, "resubmit --> %d\n", status);
342}
343
344/* USB 2.0 spec Section 11.24.2.3 */
345static inline int
346hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
347{
348 return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
349 HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
350 tt, NULL, 0, 1000);
351}
352
353/*
354 * enumeration blocks khubd for a long time. we use keventd instead, since
355 * long blocking there is the exception, not the rule. accordingly, HCDs
356 * talking to TTs must queue control transfers (not just bulk and iso), so
357 * both can talk to the same hub concurrently.
358 */
359static void hub_tt_kevent (void *arg)
360{
361 struct usb_hub *hub = arg;
362 unsigned long flags;
363
364 spin_lock_irqsave (&hub->tt.lock, flags);
365 while (!list_empty (&hub->tt.clear_list)) {
366 struct list_head *temp;
367 struct usb_tt_clear *clear;
368 struct usb_device *hdev = hub->hdev;
369 int status;
370
371 temp = hub->tt.clear_list.next;
372 clear = list_entry (temp, struct usb_tt_clear, clear_list);
373 list_del (&clear->clear_list);
374
375 /* drop lock so HCD can concurrently report other TT errors */
376 spin_unlock_irqrestore (&hub->tt.lock, flags);
377 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
378 spin_lock_irqsave (&hub->tt.lock, flags);
379
380 if (status)
381 dev_err (&hdev->dev,
382 "clear tt %d (%04x) error %d\n",
383 clear->tt, clear->devinfo, status);
384 kfree (clear);
385 }
386 spin_unlock_irqrestore (&hub->tt.lock, flags);
387}
388
389/**
390 * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
391 * @udev: the device whose split transaction failed
392 * @pipe: identifies the endpoint of the failed transaction
393 *
394 * High speed HCDs use this to tell the hub driver that some split control or
395 * bulk transaction failed in a way that requires clearing internal state of
396 * a transaction translator. This is normally detected (and reported) from
397 * interrupt context.
398 *
399 * It may not be possible for that hub to handle additional full (or low)
400 * speed transactions until that state is fully cleared out.
401 */
402void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
403{
404 struct usb_tt *tt = udev->tt;
405 unsigned long flags;
406 struct usb_tt_clear *clear;
407
408 /* we've got to cope with an arbitrary number of pending TT clears,
409 * since each TT has "at least two" buffers that can need it (and
410 * there can be many TTs per hub). even if they're uncommon.
411 */
412 if ((clear = kmalloc (sizeof *clear, SLAB_ATOMIC)) == NULL) {
413 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
414 /* FIXME recover somehow ... RESET_TT? */
415 return;
416 }
417
418 /* info that CLEAR_TT_BUFFER needs */
419 clear->tt = tt->multi ? udev->ttport : 1;
420 clear->devinfo = usb_pipeendpoint (pipe);
421 clear->devinfo |= udev->devnum << 4;
422 clear->devinfo |= usb_pipecontrol (pipe)
423 ? (USB_ENDPOINT_XFER_CONTROL << 11)
424 : (USB_ENDPOINT_XFER_BULK << 11);
425 if (usb_pipein (pipe))
426 clear->devinfo |= 1 << 15;
427
428 /* tell keventd to clear state for this TT */
429 spin_lock_irqsave (&tt->lock, flags);
430 list_add_tail (&clear->clear_list, &tt->clear_list);
431 schedule_work (&tt->kevent);
432 spin_unlock_irqrestore (&tt->lock, flags);
433}
434
435static void hub_power_on(struct usb_hub *hub)
436{
437 int port1;
438
439 /* if hub supports power switching, enable power on each port */
440 if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_LPSM) < 2) {
441 dev_dbg(hub->intfdev, "enabling power on all ports\n");
442 for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
443 set_port_feature(hub->hdev, port1,
444 USB_PORT_FEAT_POWER);
445 }
446
447 /* Wait for power to be enabled */
448 msleep(hub->descriptor->bPwrOn2PwrGood * 2);
449}
450
451static void hub_quiesce(struct usb_hub *hub)
452{
453 /* stop khubd and related activity */
454 hub->quiescing = 1;
455 usb_kill_urb(hub->urb);
456 if (hub->has_indicators)
457 cancel_delayed_work(&hub->leds);
458 if (hub->has_indicators || hub->tt.hub)
459 flush_scheduled_work();
460}
461
462static void hub_activate(struct usb_hub *hub)
463{
464 int status;
465
466 hub->quiescing = 0;
467 hub->activating = 1;
468 status = usb_submit_urb(hub->urb, GFP_NOIO);
469 if (status < 0)
470 dev_err(hub->intfdev, "activate --> %d\n", status);
471 if (hub->has_indicators && blinkenlights)
472 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
473
474 /* scan all ports ASAP */
475 kick_khubd(hub);
476}
477
478static int hub_hub_status(struct usb_hub *hub,
479 u16 *status, u16 *change)
480{
481 int ret;
482
483 ret = get_hub_status(hub->hdev, &hub->status->hub);
484 if (ret < 0)
485 dev_err (hub->intfdev,
486 "%s failed (err = %d)\n", __FUNCTION__, ret);
487 else {
488 *status = le16_to_cpu(hub->status->hub.wHubStatus);
489 *change = le16_to_cpu(hub->status->hub.wHubChange);
490 ret = 0;
491 }
492 return ret;
493}
494
495static int hub_configure(struct usb_hub *hub,
496 struct usb_endpoint_descriptor *endpoint)
497{
498 struct usb_device *hdev = hub->hdev;
499 struct device *hub_dev = hub->intfdev;
500 u16 hubstatus, hubchange;
501 unsigned int pipe;
502 int maxp, ret;
503 char *message;
504
505 hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
506 &hub->buffer_dma);
507 if (!hub->buffer) {
508 message = "can't allocate hub irq buffer";
509 ret = -ENOMEM;
510 goto fail;
511 }
512
513 hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
514 if (!hub->status) {
515 message = "can't kmalloc hub status buffer";
516 ret = -ENOMEM;
517 goto fail;
518 }
519
520 hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
521 if (!hub->descriptor) {
522 message = "can't kmalloc hub descriptor";
523 ret = -ENOMEM;
524 goto fail;
525 }
526
527 /* Request the entire hub descriptor.
528 * hub->descriptor can handle USB_MAXCHILDREN ports,
529 * but the hub can/will return fewer bytes here.
530 */
531 ret = get_hub_descriptor(hdev, hub->descriptor,
532 sizeof(*hub->descriptor));
533 if (ret < 0) {
534 message = "can't read hub descriptor";
535 goto fail;
536 } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
537 message = "hub has too many ports!";
538 ret = -ENODEV;
539 goto fail;
540 }
541
542 hdev->maxchild = hub->descriptor->bNbrPorts;
543 dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
544 (hdev->maxchild == 1) ? "" : "s");
545
546 le16_to_cpus(&hub->descriptor->wHubCharacteristics);
547
548 if (hub->descriptor->wHubCharacteristics & HUB_CHAR_COMPOUND) {
549 int i;
550 char portstr [USB_MAXCHILDREN + 1];
551
552 for (i = 0; i < hdev->maxchild; i++)
553 portstr[i] = hub->descriptor->DeviceRemovable
554 [((i + 1) / 8)] & (1 << ((i + 1) % 8))
555 ? 'F' : 'R';
556 portstr[hdev->maxchild] = 0;
557 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
558 } else
559 dev_dbg(hub_dev, "standalone hub\n");
560
561 switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_LPSM) {
562 case 0x00:
563 dev_dbg(hub_dev, "ganged power switching\n");
564 break;
565 case 0x01:
566 dev_dbg(hub_dev, "individual port power switching\n");
567 break;
568 case 0x02:
569 case 0x03:
570 dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
571 break;
572 }
573
574 switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) {
575 case 0x00:
576 dev_dbg(hub_dev, "global over-current protection\n");
577 break;
578 case 0x08:
579 dev_dbg(hub_dev, "individual port over-current protection\n");
580 break;
581 case 0x10:
582 case 0x18:
583 dev_dbg(hub_dev, "no over-current protection\n");
584 break;
585 }
586
587 spin_lock_init (&hub->tt.lock);
588 INIT_LIST_HEAD (&hub->tt.clear_list);
589 INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub);
590 switch (hdev->descriptor.bDeviceProtocol) {
591 case 0:
592 break;
593 case 1:
594 dev_dbg(hub_dev, "Single TT\n");
595 hub->tt.hub = hdev;
596 break;
597 case 2:
598 ret = usb_set_interface(hdev, 0, 1);
599 if (ret == 0) {
600 dev_dbg(hub_dev, "TT per port\n");
601 hub->tt.multi = 1;
602 } else
603 dev_err(hub_dev, "Using single TT (err %d)\n",
604 ret);
605 hub->tt.hub = hdev;
606 break;
607 default:
608 dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
609 hdev->descriptor.bDeviceProtocol);
610 break;
611 }
612
613 switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_TTTT) {
614 case 0x00:
615 if (hdev->descriptor.bDeviceProtocol != 0)
616 dev_dbg(hub_dev, "TT requires at most 8 FS bit times\n");
617 break;
618 case 0x20:
619 dev_dbg(hub_dev, "TT requires at most 16 FS bit times\n");
620 break;
621 case 0x40:
622 dev_dbg(hub_dev, "TT requires at most 24 FS bit times\n");
623 break;
624 case 0x60:
625 dev_dbg(hub_dev, "TT requires at most 32 FS bit times\n");
626 break;
627 }
628
629 /* probe() zeroes hub->indicator[] */
630 if (hub->descriptor->wHubCharacteristics & HUB_CHAR_PORTIND) {
631 hub->has_indicators = 1;
632 dev_dbg(hub_dev, "Port indicators are supported\n");
633 }
634
635 dev_dbg(hub_dev, "power on to power good time: %dms\n",
636 hub->descriptor->bPwrOn2PwrGood * 2);
637
638 /* power budgeting mostly matters with bus-powered hubs,
639 * and battery-powered root hubs (may provide just 8 mA).
640 */
641 ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
642 if (ret < 0) {
643 message = "can't get hub status";
644 goto fail;
645 }
646 cpu_to_le16s(&hubstatus);
647 if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
648 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
649 hub->descriptor->bHubContrCurrent);
650 hub->power_budget = (501 - hub->descriptor->bHubContrCurrent)
651 / 2;
652 dev_dbg(hub_dev, "%dmA bus power budget for children\n",
653 hub->power_budget * 2);
654 }
655
656
657 ret = hub_hub_status(hub, &hubstatus, &hubchange);
658 if (ret < 0) {
659 message = "can't get hub status";
660 goto fail;
661 }
662
663 /* local power status reports aren't always correct */
664 if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
665 dev_dbg(hub_dev, "local power source is %s\n",
666 (hubstatus & HUB_STATUS_LOCAL_POWER)
667 ? "lost (inactive)" : "good");
668
669 if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) == 0)
670 dev_dbg(hub_dev, "%sover-current condition exists\n",
671 (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
672
673 /* set up the interrupt endpoint */
674 pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
675 maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
676
677 if (maxp > sizeof(*hub->buffer))
678 maxp = sizeof(*hub->buffer);
679
680 hub->urb = usb_alloc_urb(0, GFP_KERNEL);
681 if (!hub->urb) {
682 message = "couldn't allocate interrupt urb";
683 ret = -ENOMEM;
684 goto fail;
685 }
686
687 usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
688 hub, endpoint->bInterval);
689 hub->urb->transfer_dma = hub->buffer_dma;
690 hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
691
692 /* maybe cycle the hub leds */
693 if (hub->has_indicators && blinkenlights)
694 hub->indicator [0] = INDICATOR_CYCLE;
695
696 hub_power_on(hub);
697 hub_activate(hub);
698 return 0;
699
700fail:
701 dev_err (hub_dev, "config failed, %s (err %d)\n",
702 message, ret);
703 /* hub_disconnect() frees urb and descriptor */
704 return ret;
705}
706
707static unsigned highspeed_hubs;
708
709static void hub_disconnect(struct usb_interface *intf)
710{
711 struct usb_hub *hub = usb_get_intfdata (intf);
712 struct usb_device *hdev;
713
714 if (!hub)
715 return;
716 hdev = hub->hdev;
717
718 if (hdev->speed == USB_SPEED_HIGH)
719 highspeed_hubs--;
720
721 usb_set_intfdata (intf, NULL);
722
723 hub_quiesce(hub);
724 usb_free_urb(hub->urb);
725 hub->urb = NULL;
726
727 spin_lock_irq(&hub_event_lock);
728 list_del_init(&hub->event_list);
729 spin_unlock_irq(&hub_event_lock);
730
731 if (hub->descriptor) {
732 kfree(hub->descriptor);
733 hub->descriptor = NULL;
734 }
735
736 if (hub->status) {
737 kfree(hub->status);
738 hub->status = NULL;
739 }
740
741 if (hub->buffer) {
742 usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
743 hub->buffer_dma);
744 hub->buffer = NULL;
745 }
746
747 /* Free the memory */
748 kfree(hub);
749}
750
751static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
752{
753 struct usb_host_interface *desc;
754 struct usb_endpoint_descriptor *endpoint;
755 struct usb_device *hdev;
756 struct usb_hub *hub;
757
758 desc = intf->cur_altsetting;
759 hdev = interface_to_usbdev(intf);
760
761 /* Some hubs have a subclass of 1, which AFAICT according to the */
762 /* specs is not defined, but it works */
763 if ((desc->desc.bInterfaceSubClass != 0) &&
764 (desc->desc.bInterfaceSubClass != 1)) {
765descriptor_error:
766 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
767 return -EIO;
768 }
769
770 /* Multiple endpoints? What kind of mutant ninja-hub is this? */
771 if (desc->desc.bNumEndpoints != 1)
772 goto descriptor_error;
773
774 endpoint = &desc->endpoint[0].desc;
775
776 /* Output endpoint? Curiouser and curiouser.. */
777 if (!(endpoint->bEndpointAddress & USB_DIR_IN))
778 goto descriptor_error;
779
780 /* If it's not an interrupt endpoint, we'd better punt! */
781 if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
782 != USB_ENDPOINT_XFER_INT)
783 goto descriptor_error;
784
785 /* We found a hub */
786 dev_info (&intf->dev, "USB hub found\n");
787
788 hub = kmalloc(sizeof(*hub), GFP_KERNEL);
789 if (!hub) {
790 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
791 return -ENOMEM;
792 }
793
794 memset(hub, 0, sizeof(*hub));
795
796 INIT_LIST_HEAD(&hub->event_list);
797 hub->intfdev = &intf->dev;
798 hub->hdev = hdev;
799 INIT_WORK(&hub->leds, led_work, hub);
800
801 usb_set_intfdata (intf, hub);
802
803 if (hdev->speed == USB_SPEED_HIGH)
804 highspeed_hubs++;
805
806 if (hub_configure(hub, endpoint) >= 0)
807 return 0;
808
809 hub_disconnect (intf);
810 return -ENODEV;
811}
812
813static int
814hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
815{
816 struct usb_device *hdev = interface_to_usbdev (intf);
817
818 /* assert ifno == 0 (part of hub spec) */
819 switch (code) {
820 case USBDEVFS_HUB_PORTINFO: {
821 struct usbdevfs_hub_portinfo *info = user_data;
822 int i;
823
824 spin_lock_irq(&device_state_lock);
825 if (hdev->devnum <= 0)
826 info->nports = 0;
827 else {
828 info->nports = hdev->maxchild;
829 for (i = 0; i < info->nports; i++) {
830 if (hdev->children[i] == NULL)
831 info->port[i] = 0;
832 else
833 info->port[i] =
834 hdev->children[i]->devnum;
835 }
836 }
837 spin_unlock_irq(&device_state_lock);
838
839 return info->nports + 1;
840 }
841
842 default:
843 return -ENOSYS;
844 }
845}
846
847/* caller has locked the hub device */
848static void hub_pre_reset(struct usb_hub *hub)
849{
850 struct usb_device *hdev = hub->hdev;
851 int i;
852
853 for (i = 0; i < hdev->maxchild; ++i) {
854 if (hdev->children[i])
855 usb_disconnect(&hdev->children[i]);
856 }
857 hub_quiesce(hub);
858}
859
860/* caller has locked the hub device */
861static void hub_post_reset(struct usb_hub *hub)
862{
863 hub_activate(hub);
864 hub_power_on(hub);
865}
866
867
868/* grab device/port lock, returning index of that port (zero based).
869 * protects the upstream link used by this device from concurrent
870 * tree operations like suspend, resume, reset, and disconnect, which
871 * apply to everything downstream of a given port.
872 */
873static int locktree(struct usb_device *udev)
874{
875 int t;
876 struct usb_device *hdev;
877
878 if (!udev)
879 return -ENODEV;
880
881 /* root hub is always the first lock in the series */
882 hdev = udev->parent;
883 if (!hdev) {
884 usb_lock_device(udev);
885 return 0;
886 }
887
888 /* on the path from root to us, lock everything from
889 * top down, dropping parent locks when not needed
890 */
891 t = locktree(hdev);
892 if (t < 0)
893 return t;
894 for (t = 0; t < hdev->maxchild; t++) {
895 if (hdev->children[t] == udev) {
896 /* everything is fail-fast once disconnect
897 * processing starts
898 */
899 if (udev->state == USB_STATE_NOTATTACHED)
900 break;
901
902 /* when everyone grabs locks top->bottom,
903 * non-overlapping work may be concurrent
904 */
905 down(&udev->serialize);
906 up(&hdev->serialize);
907 return t + 1;
908 }
909 }
910 usb_unlock_device(hdev);
911 return -ENODEV;
912}
913
914static void recursively_mark_NOTATTACHED(struct usb_device *udev)
915{
916 int i;
917
918 for (i = 0; i < udev->maxchild; ++i) {
919 if (udev->children[i])
920 recursively_mark_NOTATTACHED(udev->children[i]);
921 }
922 udev->state = USB_STATE_NOTATTACHED;
923}
924
925/**
926 * usb_set_device_state - change a device's current state (usbcore, hcds)
927 * @udev: pointer to device whose state should be changed
928 * @new_state: new state value to be stored
929 *
930 * udev->state is _not_ fully protected by the device lock. Although
931 * most transitions are made only while holding the lock, the state can
932 * can change to USB_STATE_NOTATTACHED at almost any time. This
933 * is so that devices can be marked as disconnected as soon as possible,
934 * without having to wait for any semaphores to be released. As a result,
935 * all changes to any device's state must be protected by the
936 * device_state_lock spinlock.
937 *
938 * Once a device has been added to the device tree, all changes to its state
939 * should be made using this routine. The state should _not_ be set directly.
940 *
941 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
942 * Otherwise udev->state is set to new_state, and if new_state is
943 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
944 * to USB_STATE_NOTATTACHED.
945 */
946void usb_set_device_state(struct usb_device *udev,
947 enum usb_device_state new_state)
948{
949 unsigned long flags;
950
951 spin_lock_irqsave(&device_state_lock, flags);
952 if (udev->state == USB_STATE_NOTATTACHED)
953 ; /* do nothing */
954 else if (new_state != USB_STATE_NOTATTACHED)
955 udev->state = new_state;
956 else
957 recursively_mark_NOTATTACHED(udev);
958 spin_unlock_irqrestore(&device_state_lock, flags);
959}
960EXPORT_SYMBOL(usb_set_device_state);
961
962
963static void choose_address(struct usb_device *udev)
964{
965 int devnum;
966 struct usb_bus *bus = udev->bus;
967
968 /* If khubd ever becomes multithreaded, this will need a lock */
969
970 /* Try to allocate the next devnum beginning at bus->devnum_next. */
971 devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
972 bus->devnum_next);
973 if (devnum >= 128)
974 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
975
976 bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
977
978 if (devnum < 128) {
979 set_bit(devnum, bus->devmap.devicemap);
980 udev->devnum = devnum;
981 }
982}
983
984static void release_address(struct usb_device *udev)
985{
986 if (udev->devnum > 0) {
987 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
988 udev->devnum = -1;
989 }
990}
991
992/**
993 * usb_disconnect - disconnect a device (usbcore-internal)
994 * @pdev: pointer to device being disconnected
995 * Context: !in_interrupt ()
996 *
997 * Something got disconnected. Get rid of it and all of its children.
998 *
999 * If *pdev is a normal device then the parent hub must already be locked.
1000 * If *pdev is a root hub then this routine will acquire the
1001 * usb_bus_list_lock on behalf of the caller.
1002 *
1003 * Only hub drivers (including virtual root hub drivers for host
1004 * controllers) should ever call this.
1005 *
1006 * This call is synchronous, and may not be used in an interrupt context.
1007 */
1008void usb_disconnect(struct usb_device **pdev)
1009{
1010 struct usb_device *udev = *pdev;
1011 int i;
1012
1013 if (!udev) {
1014 pr_debug ("%s nodev\n", __FUNCTION__);
1015 return;
1016 }
1017
1018 /* mark the device as inactive, so any further urb submissions for
1019 * this device (and any of its children) will fail immediately.
1020 * this quiesces everyting except pending urbs.
1021 */
1022 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1023
1024 /* lock the bus list on behalf of HCDs unregistering their root hubs */
1025 if (!udev->parent) {
1026 down(&usb_bus_list_lock);
1027 usb_lock_device(udev);
1028 } else
1029 down(&udev->serialize);
1030
1031 dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1032
1033 /* Free up all the children before we remove this device */
1034 for (i = 0; i < USB_MAXCHILDREN; i++) {
1035 if (udev->children[i])
1036 usb_disconnect(&udev->children[i]);
1037 }
1038
1039 /* deallocate hcd/hardware state ... nuking all pending urbs and
1040 * cleaning up all state associated with the current configuration
1041 * so that the hardware is now fully quiesced.
1042 */
1043 usb_disable_device(udev, 0);
1044
1045 /* Free the device number, remove the /proc/bus/usb entry and
1046 * the sysfs attributes, and delete the parent's children[]
1047 * (or root_hub) pointer.
1048 */
1049 dev_dbg (&udev->dev, "unregistering device\n");
1050 release_address(udev);
1051 usbfs_remove_device(udev);
1052 usb_remove_sysfs_dev_files(udev);
1053
1054 /* Avoid races with recursively_mark_NOTATTACHED() */
1055 spin_lock_irq(&device_state_lock);
1056 *pdev = NULL;
1057 spin_unlock_irq(&device_state_lock);
1058
1059 if (!udev->parent) {
1060 usb_unlock_device(udev);
1061 up(&usb_bus_list_lock);
1062 } else
1063 up(&udev->serialize);
1064
1065 device_unregister(&udev->dev);
1066}
1067
1068static int choose_configuration(struct usb_device *udev)
1069{
1070 int c, i;
1071
1072 /* NOTE: this should interact with hub power budgeting */
1073
1074 c = udev->config[0].desc.bConfigurationValue;
1075 if (udev->descriptor.bNumConfigurations != 1) {
1076 for (i = 0; i < udev->descriptor.bNumConfigurations; i++) {
1077 struct usb_interface_descriptor *desc;
1078
1079 /* heuristic: Linux is more likely to have class
1080 * drivers, so avoid vendor-specific interfaces.
1081 */
1082 desc = &udev->config[i].intf_cache[0]
1083 ->altsetting->desc;
1084 if (desc->bInterfaceClass == USB_CLASS_VENDOR_SPEC)
1085 continue;
1086 /* COMM/2/all is CDC ACM, except 0xff is MSFT RNDIS.
1087 * MSFT needs this to be the first config; never use
1088 * it as the default unless Linux has host-side RNDIS.
1089 * A second config would ideally be CDC-Ethernet, but
1090 * may instead be the "vendor specific" CDC subset
1091 * long used by ARM Linux for sa1100 or pxa255.
1092 */
1093 if (desc->bInterfaceClass == USB_CLASS_COMM
1094 && desc->bInterfaceSubClass == 2
1095 && desc->bInterfaceProtocol == 0xff) {
1096 c = udev->config[1].desc.bConfigurationValue;
1097 continue;
1098 }
1099 c = udev->config[i].desc.bConfigurationValue;
1100 break;
1101 }
1102 dev_info(&udev->dev,
1103 "configuration #%d chosen from %d choices\n",
1104 c, udev->descriptor.bNumConfigurations);
1105 }
1106 return c;
1107}
1108
1109#ifdef DEBUG
1110static void show_string(struct usb_device *udev, char *id, char *string)
1111{
1112 if (!string)
1113 return;
1114 dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1115}
1116
1117#else
1118static inline void show_string(struct usb_device *udev, char *id, char *string)
1119{}
1120#endif
1121
1122static void get_string(struct usb_device *udev, char **string, int index)
1123{
1124 char *buf;
1125
1126 if (!index)
1127 return;
1128 buf = kmalloc(256, GFP_KERNEL);
1129 if (!buf)
1130 return;
1131 if (usb_string(udev, index, buf, 256) > 0)
1132 *string = buf;
1133 else
1134 kfree(buf);
1135}
1136
1137
1138#ifdef CONFIG_USB_OTG
1139#include "otg_whitelist.h"
1140#endif
1141
1142/**
1143 * usb_new_device - perform initial device setup (usbcore-internal)
1144 * @udev: newly addressed device (in ADDRESS state)
1145 *
1146 * This is called with devices which have been enumerated, but not yet
1147 * configured. The device descriptor is available, but not descriptors
1148 * for any device configuration. The caller must have locked udev and
1149 * either the parent hub (if udev is a normal device) or else the
1150 * usb_bus_list_lock (if udev is a root hub). The parent's pointer to
1151 * udev has already been installed, but udev is not yet visible through
1152 * sysfs or other filesystem code.
1153 *
1154 * Returns 0 for success (device is configured and listed, with its
1155 * interfaces, in sysfs); else a negative errno value.
1156 *
1157 * This call is synchronous, and may not be used in an interrupt context.
1158 *
1159 * Only the hub driver should ever call this; root hub registration
1160 * uses it indirectly.
1161 */
1162int usb_new_device(struct usb_device *udev)
1163{
1164 int err;
1165 int c;
1166
1167 err = usb_get_configuration(udev);
1168 if (err < 0) {
1169 dev_err(&udev->dev, "can't read configurations, error %d\n",
1170 err);
1171 goto fail;
1172 }
1173
1174 /* read the standard strings and cache them if present */
1175 get_string(udev, &udev->product, udev->descriptor.iProduct);
1176 get_string(udev, &udev->manufacturer, udev->descriptor.iManufacturer);
1177 get_string(udev, &udev->serial, udev->descriptor.iSerialNumber);
1178
1179 /* Tell the world! */
1180 dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1181 "SerialNumber=%d\n",
1182 udev->descriptor.iManufacturer,
1183 udev->descriptor.iProduct,
1184 udev->descriptor.iSerialNumber);
1185 show_string(udev, "Product", udev->product);
1186 show_string(udev, "Manufacturer", udev->manufacturer);
1187 show_string(udev, "SerialNumber", udev->serial);
1188
1189#ifdef CONFIG_USB_OTG
1190 /*
1191 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1192 * to wake us after we've powered off VBUS; and HNP, switching roles
1193 * "host" to "peripheral". The OTG descriptor helps figure this out.
1194 */
1195 if (!udev->bus->is_b_host
1196 && udev->config
1197 && udev->parent == udev->bus->root_hub) {
1198 struct usb_otg_descriptor *desc = 0;
1199 struct usb_bus *bus = udev->bus;
1200
1201 /* descriptor may appear anywhere in config */
1202 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1203 le16_to_cpu(udev->config[0].desc.wTotalLength),
1204 USB_DT_OTG, (void **) &desc) == 0) {
1205 if (desc->bmAttributes & USB_OTG_HNP) {
1206 unsigned port1;
1207 struct usb_device *root = udev->parent;
1208
1209 for (port1 = 1; port1 <= root->maxchild;
1210 port1++) {
1211 if (root->children[port1-1] == udev)
1212 break;
1213 }
1214
1215 dev_info(&udev->dev,
1216 "Dual-Role OTG device on %sHNP port\n",
1217 (port1 == bus->otg_port)
1218 ? "" : "non-");
1219
1220 /* enable HNP before suspend, it's simpler */
1221 if (port1 == bus->otg_port)
1222 bus->b_hnp_enable = 1;
1223 err = usb_control_msg(udev,
1224 usb_sndctrlpipe(udev, 0),
1225 USB_REQ_SET_FEATURE, 0,
1226 bus->b_hnp_enable
1227 ? USB_DEVICE_B_HNP_ENABLE
1228 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1229 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1230 if (err < 0) {
1231 /* OTG MESSAGE: report errors here,
1232 * customize to match your product.
1233 */
1234 dev_info(&udev->dev,
1235 "can't set HNP mode; %d\n",
1236 err);
1237 bus->b_hnp_enable = 0;
1238 }
1239 }
1240 }
1241 }
1242
1243 if (!is_targeted(udev)) {
1244
1245 /* Maybe it can talk to us, though we can't talk to it.
1246 * (Includes HNP test device.)
1247 */
1248 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1249 static int __usb_suspend_device (struct usb_device *,
1250 int port1, pm_message_t state);
1251 err = __usb_suspend_device(udev,
1252 udev->bus->otg_port,
1253 PMSG_SUSPEND);
1254 if (err < 0)
1255 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1256 }
1257 err = -ENODEV;
1258 goto fail;
1259 }
1260#endif
1261
1262 /* put device-specific files into sysfs */
1263 err = device_add (&udev->dev);
1264 if (err) {
1265 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1266 goto fail;
1267 }
1268 usb_create_sysfs_dev_files (udev);
1269
1270 /* choose and set the configuration. that registers the interfaces
1271 * with the driver core, and lets usb device drivers bind to them.
1272 */
1273 c = choose_configuration(udev);
1274 if (c < 0)
1275 dev_warn(&udev->dev,
1276 "can't choose an initial configuration\n");
1277 else {
1278 err = usb_set_configuration(udev, c);
1279 if (err) {
1280 dev_err(&udev->dev, "can't set config #%d, error %d\n",
1281 c, err);
1282 usb_remove_sysfs_dev_files(udev);
1283 device_del(&udev->dev);
1284 goto fail;
1285 }
1286 }
1287
1288 /* USB device state == configured ... usable */
1289
1290 /* add a /proc/bus/usb entry */
1291 usbfs_add_device(udev);
1292 return 0;
1293
1294fail:
1295 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1296 return err;
1297}
1298
1299
1300static int hub_port_status(struct usb_hub *hub, int port1,
1301 u16 *status, u16 *change)
1302{
1303 int ret;
1304
1305 ret = get_port_status(hub->hdev, port1, &hub->status->port);
1306 if (ret < 0)
1307 dev_err (hub->intfdev,
1308 "%s failed (err = %d)\n", __FUNCTION__, ret);
1309 else {
1310 *status = le16_to_cpu(hub->status->port.wPortStatus);
1311 *change = le16_to_cpu(hub->status->port.wPortChange);
1312 ret = 0;
1313 }
1314 return ret;
1315}
1316
1317#define PORT_RESET_TRIES 5
1318#define SET_ADDRESS_TRIES 2
1319#define GET_DESCRIPTOR_TRIES 2
1320#define SET_CONFIG_TRIES (2 * (use_both_schemes + 1))
1321#define USE_NEW_SCHEME(i) ((i) / 2 == old_scheme_first)
1322
1323#define HUB_ROOT_RESET_TIME 50 /* times are in msec */
1324#define HUB_SHORT_RESET_TIME 10
1325#define HUB_LONG_RESET_TIME 200
1326#define HUB_RESET_TIMEOUT 500
1327
1328static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1329 struct usb_device *udev, unsigned int delay)
1330{
1331 int delay_time, ret;
1332 u16 portstatus;
1333 u16 portchange;
1334
1335 for (delay_time = 0;
1336 delay_time < HUB_RESET_TIMEOUT;
1337 delay_time += delay) {
1338 /* wait to give the device a chance to reset */
1339 msleep(delay);
1340
1341 /* read and decode port status */
1342 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1343 if (ret < 0)
1344 return ret;
1345
1346 /* Device went away? */
1347 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1348 return -ENOTCONN;
1349
1350 /* bomb out completely if something weird happened */
1351 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1352 return -EINVAL;
1353
1354 /* if we`ve finished resetting, then break out of the loop */
1355 if (!(portstatus & USB_PORT_STAT_RESET) &&
1356 (portstatus & USB_PORT_STAT_ENABLE)) {
1357 if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1358 udev->speed = USB_SPEED_HIGH;
1359 else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1360 udev->speed = USB_SPEED_LOW;
1361 else
1362 udev->speed = USB_SPEED_FULL;
1363 return 0;
1364 }
1365
1366 /* switch to the long delay after two short delay failures */
1367 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1368 delay = HUB_LONG_RESET_TIME;
1369
1370 dev_dbg (hub->intfdev,
1371 "port %d not reset yet, waiting %dms\n",
1372 port1, delay);
1373 }
1374
1375 return -EBUSY;
1376}
1377
1378static int hub_port_reset(struct usb_hub *hub, int port1,
1379 struct usb_device *udev, unsigned int delay)
1380{
1381 int i, status;
1382
1383 /* Reset the port */
1384 for (i = 0; i < PORT_RESET_TRIES; i++) {
1385 status = set_port_feature(hub->hdev,
1386 port1, USB_PORT_FEAT_RESET);
1387 if (status)
1388 dev_err(hub->intfdev,
1389 "cannot reset port %d (err = %d)\n",
1390 port1, status);
1391 else {
1392 status = hub_port_wait_reset(hub, port1, udev, delay);
1393 if (status)
1394 dev_dbg(hub->intfdev,
1395 "port_wait_reset: err = %d\n",
1396 status);
1397 }
1398
1399 /* return on disconnect or reset */
1400 switch (status) {
1401 case 0:
1402 /* TRSTRCY = 10 ms */
1403 msleep(10);
1404 /* FALL THROUGH */
1405 case -ENOTCONN:
1406 case -ENODEV:
1407 clear_port_feature(hub->hdev,
1408 port1, USB_PORT_FEAT_C_RESET);
1409 /* FIXME need disconnect() for NOTATTACHED device */
1410 usb_set_device_state(udev, status
1411 ? USB_STATE_NOTATTACHED
1412 : USB_STATE_DEFAULT);
1413 return status;
1414 }
1415
1416 dev_dbg (hub->intfdev,
1417 "port %d not enabled, trying reset again...\n",
1418 port1);
1419 delay = HUB_LONG_RESET_TIME;
1420 }
1421
1422 dev_err (hub->intfdev,
1423 "Cannot enable port %i. Maybe the USB cable is bad?\n",
1424 port1);
1425
1426 return status;
1427}
1428
1429static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
1430{
1431 struct usb_device *hdev = hub->hdev;
1432 int ret;
1433
1434 if (hdev->children[port1-1] && set_state) {
1435 usb_set_device_state(hdev->children[port1-1],
1436 USB_STATE_NOTATTACHED);
1437 }
1438 ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
1439 if (ret)
1440 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
1441 port1, ret);
1442
1443 return ret;
1444}
1445
1446/*
1447 * Disable a port and mark a logical connnect-change event, so that some
1448 * time later khubd will disconnect() any existing usb_device on the port
1449 * and will re-enumerate if there actually is a device attached.
1450 */
1451static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1452{
1453 dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1454 hub_port_disable(hub, port1, 1);
1455
1456 /* FIXME let caller ask to power down the port:
1457 * - some devices won't enumerate without a VBUS power cycle
1458 * - SRP saves power that way
1459 * - usb_suspend_device(dev,PM_SUSPEND_DISK)
1460 * That's easy if this hub can switch power per-port, and
1461 * khubd reactivates the port later (timer, SRP, etc).
1462 * Powerdown must be optional, because of reset/DFU.
1463 */
1464
1465 set_bit(port1, hub->change_bits);
1466 kick_khubd(hub);
1467}
1468
1469
1470#ifdef CONFIG_USB_SUSPEND
1471
1472/*
1473 * Selective port suspend reduces power; most suspended devices draw
1474 * less than 500 uA. It's also used in OTG, along with remote wakeup.
1475 * All devices below the suspended port are also suspended.
1476 *
1477 * Devices leave suspend state when the host wakes them up. Some devices
1478 * also support "remote wakeup", where the device can activate the USB
1479 * tree above them to deliver data, such as a keypress or packet. In
1480 * some cases, this wakes the USB host.
1481 */
1482static int hub_port_suspend(struct usb_hub *hub, int port1,
1483 struct usb_device *udev)
1484{
1485 int status;
1486
1487 // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1488
1489 /* enable remote wakeup when appropriate; this lets the device
1490 * wake up the upstream hub (including maybe the root hub).
1491 *
1492 * NOTE: OTG devices may issue remote wakeup (or SRP) even when
1493 * we don't explicitly enable it here.
1494 */
1495 if (udev->actconfig
1496 // && FIXME (remote wakeup enabled on this bus)
1497 // ... currently assuming it's always appropriate
1498 && (udev->actconfig->desc.bmAttributes
1499 & USB_CONFIG_ATT_WAKEUP) != 0) {
1500 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1501 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1502 USB_DEVICE_REMOTE_WAKEUP, 0,
1503 NULL, 0,
1504 USB_CTRL_SET_TIMEOUT);
1505 if (status)
1506 dev_dbg(&udev->dev,
1507 "won't remote wakeup, status %d\n",
1508 status);
1509 }
1510
1511 /* see 7.1.7.6 */
1512 status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1513 if (status) {
1514 dev_dbg(hub->intfdev,
1515 "can't suspend port %d, status %d\n",
1516 port1, status);
1517 /* paranoia: "should not happen" */
1518 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1519 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1520 USB_DEVICE_REMOTE_WAKEUP, 0,
1521 NULL, 0,
1522 USB_CTRL_SET_TIMEOUT);
1523 } else {
1524 /* device has up to 10 msec to fully suspend */
1525 dev_dbg(&udev->dev, "usb suspend\n");
1526 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1527 msleep(10);
1528 }
1529 return status;
1530}
1531
1532/*
1533 * Devices on USB hub ports have only one "suspend" state, corresponding
1534 * to ACPI D2 (PM_SUSPEND_MEM), "may cause the device to lose some context".
1535 * State transitions include:
1536 *
1537 * - suspend, resume ... when the VBUS power link stays live
1538 * - suspend, disconnect ... VBUS lost
1539 *
1540 * Once VBUS drop breaks the circuit, the port it's using has to go through
1541 * normal re-enumeration procedures, starting with enabling VBUS power.
1542 * Other than re-initializing the hub (plug/unplug, except for root hubs),
1543 * Linux (2.6) currently has NO mechanisms to initiate that: no khubd
1544 * timer, no SRP, no requests through sysfs.
1545 */
1546static int __usb_suspend_device (struct usb_device *udev, int port1,
1547 pm_message_t state)
1548{
1549 int status;
1550
1551 /* caller owns the udev device lock */
1552 if (port1 < 0)
1553 return port1;
1554
1555 if (udev->state == USB_STATE_SUSPENDED
1556 || udev->state == USB_STATE_NOTATTACHED) {
1557 return 0;
1558 }
1559
1560 /* suspend interface drivers; if this is a hub, it
1561 * suspends the child devices
1562 */
1563 if (udev->actconfig) {
1564 int i;
1565
1566 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1567 struct usb_interface *intf;
1568 struct usb_driver *driver;
1569
1570 intf = udev->actconfig->interface[i];
1571 if (state <= intf->dev.power.power_state)
1572 continue;
1573 if (!intf->dev.driver)
1574 continue;
1575 driver = to_usb_driver(intf->dev.driver);
1576
1577 if (driver->suspend) {
1578 status = driver->suspend(intf, state);
1579 if (intf->dev.power.power_state != state
1580 || status)
1581 dev_err(&intf->dev,
1582 "suspend %d fail, code %d\n",
1583 state, status);
1584 }
1585
1586 /* only drivers with suspend() can ever resume();
1587 * and after power loss, even they won't.
1588 * bus_rescan_devices() can rebind drivers later.
1589 *
1590 * FIXME the PM core self-deadlocks when unbinding
1591 * drivers during suspend/resume ... everything grabs
1592 * dpm_sem (not a spinlock, ugh). we want to unbind,
1593 * since we know every driver's probe/disconnect works
1594 * even for drivers that can't suspend.
1595 */
1596 if (!driver->suspend || state > PM_SUSPEND_MEM) {
1597#if 1
1598 dev_warn(&intf->dev, "resume is unsafe!\n");
1599#else
1600 down_write(&usb_bus_type.rwsem);
1601 device_release_driver(&intf->dev);
1602 up_write(&usb_bus_type.rwsem);
1603#endif
1604 }
1605 }
1606 }
1607
1608 /*
1609 * FIXME this needs port power off call paths too, to help force
1610 * USB into the "generic" PM model. At least for devices on
1611 * ports that aren't using ganged switching (usually root hubs).
1612 *
1613 * NOTE: SRP-capable links should adopt more aggressive poweroff
1614 * policies (when HNP doesn't apply) once we have mechanisms to
1615 * turn power back on! (Likely not before 2.7...)
1616 */
1617 if (state > PM_SUSPEND_MEM) {
1618 dev_warn(&udev->dev, "no poweroff yet, suspending instead\n");
1619 }
1620
1621 /* "global suspend" of the HC-to-USB interface (root hub), or
1622 * "selective suspend" of just one hub-device link.
1623 */
1624 if (!udev->parent) {
1625 struct usb_bus *bus = udev->bus;
1626 if (bus && bus->op->hub_suspend) {
1627 status = bus->op->hub_suspend (bus);
1628 if (status == 0) {
1629 dev_dbg(&udev->dev, "usb suspend\n");
1630 usb_set_device_state(udev,
1631 USB_STATE_SUSPENDED);
1632 }
1633 } else
1634 status = -EOPNOTSUPP;
1635 } else
1636 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1637 udev);
1638
1639 if (status == 0)
1640 udev->dev.power.power_state = state;
1641 return status;
1642}
1643
1644/**
1645 * usb_suspend_device - suspend a usb device
1646 * @udev: device that's no longer in active use
1647 * @state: PMSG_SUSPEND to suspend
1648 * Context: must be able to sleep; device not locked
1649 *
1650 * Suspends a USB device that isn't in active use, conserving power.
1651 * Devices may wake out of a suspend, if anything important happens,
1652 * using the remote wakeup mechanism. They may also be taken out of
1653 * suspend by the host, using usb_resume_device(). It's also routine
1654 * to disconnect devices while they are suspended.
1655 *
1656 * Suspending OTG devices may trigger HNP, if that's been enabled
1657 * between a pair of dual-role devices. That will change roles, such
1658 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1659 *
1660 * Returns 0 on success, else negative errno.
1661 */
1662int usb_suspend_device(struct usb_device *udev, pm_message_t state)
1663{
1664 int port1, status;
1665
1666 port1 = locktree(udev);
1667 if (port1 < 0)
1668 return port1;
1669
1670 status = __usb_suspend_device(udev, port1, state);
1671 usb_unlock_device(udev);
1672 return status;
1673}
1674
1675/*
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 */
1680static 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, "usb 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 udev->dev.power.power_state = PMSG_ON;
1697
1698 /* 10.5.4.5 says be sure devices in the tree are still there.
1699 * For now let's assume the device didn't go crazy on resume,
1700 * and device drivers will know about any resume quirks.
1701 */
1702 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1703 if (status < 0)
1704 dev_dbg(&udev->dev,
1705 "gone after usb resume? status %d\n",
1706 status);
1707 else if (udev->actconfig) {
1708 unsigned i;
1709
1710 le16_to_cpus(&devstatus);
1711 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
1712 status = usb_control_msg(udev,
1713 usb_sndctrlpipe(udev, 0),
1714 USB_REQ_CLEAR_FEATURE,
1715 USB_RECIP_DEVICE,
1716 USB_DEVICE_REMOTE_WAKEUP, 0,
1717 NULL, 0,
1718 USB_CTRL_SET_TIMEOUT);
1719 if (status) {
1720 dev_dbg(&udev->dev, "disable remote "
1721 "wakeup, status %d\n", status);
1722 status = 0;
1723 }
1724 }
1725
1726 /* resume interface drivers; if this is a hub, it
1727 * resumes the child devices
1728 */
1729 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1730 struct usb_interface *intf;
1731 struct usb_driver *driver;
1732
1733 intf = udev->actconfig->interface[i];
1734 if (intf->dev.power.power_state == PM_SUSPEND_ON)
1735 continue;
1736 if (!intf->dev.driver) {
1737 /* FIXME maybe force to alt 0 */
1738 continue;
1739 }
1740 driver = to_usb_driver(intf->dev.driver);
1741
1742 /* bus_rescan_devices() may rebind drivers */
1743 if (!driver->resume)
1744 continue;
1745
1746 /* can we do better than just logging errors? */
1747 status = driver->resume(intf);
1748 if (intf->dev.power.power_state != PM_SUSPEND_ON
1749 || status)
1750 dev_dbg(&intf->dev,
1751 "resume fail, state %d code %d\n",
1752 intf->dev.power.power_state, status);
1753 }
1754 status = 0;
1755
1756 } else if (udev->devnum <= 0) {
1757 dev_dbg(&udev->dev, "bogus resume!\n");
1758 status = -EINVAL;
1759 }
1760 return status;
1761}
1762
1763static int
1764hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1765{
1766 int status;
1767
1768 // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1769
1770 /* see 7.1.7.7; affects power usage, but not budgeting */
1771 status = clear_port_feature(hub->hdev,
1772 port1, USB_PORT_FEAT_SUSPEND);
1773 if (status) {
1774 dev_dbg(hub->intfdev,
1775 "can't resume port %d, status %d\n",
1776 port1, status);
1777 } else {
1778 u16 devstatus;
1779 u16 portchange;
1780
1781 /* drive resume for at least 20 msec */
1782 if (udev)
1783 dev_dbg(&udev->dev, "RESUME\n");
1784 msleep(25);
1785
1786#define LIVE_FLAGS ( USB_PORT_STAT_POWER \
1787 | USB_PORT_STAT_ENABLE \
1788 | USB_PORT_STAT_CONNECTION)
1789
1790 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1791 * stop resume signaling. Then finish the resume
1792 * sequence.
1793 */
1794 devstatus = portchange = 0;
1795 status = hub_port_status(hub, port1,
1796 &devstatus, &portchange);
1797 if (status < 0
1798 || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
1799 || (devstatus & USB_PORT_STAT_SUSPEND) != 0
1800 ) {
1801 dev_dbg(hub->intfdev,
1802 "port %d status %04x.%04x after resume, %d\n",
1803 port1, portchange, devstatus, status);
1804 } else {
1805 /* TRSMRCY = 10 msec */
1806 msleep(10);
1807 if (udev)
1808 status = finish_port_resume(udev);
1809 }
1810 }
1811 if (status < 0)
1812 hub_port_logical_disconnect(hub, port1);
1813
1814 return status;
1815}
1816
1817static int hub_resume (struct usb_interface *intf);
1818
1819/**
1820 * usb_resume_device - re-activate a suspended usb device
1821 * @udev: device to re-activate
1822 * Context: must be able to sleep; device not locked
1823 *
1824 * This will re-activate the suspended device, increasing power usage
1825 * while letting drivers communicate again with its endpoints.
1826 * USB resume explicitly guarantees that the power session between
1827 * the host and the device is the same as it was when the device
1828 * suspended.
1829 *
1830 * Returns 0 on success, else negative errno.
1831 */
1832int usb_resume_device(struct usb_device *udev)
1833{
1834 int port1, status;
1835
1836 port1 = locktree(udev);
1837 if (port1 < 0)
1838 return port1;
1839
1840 /* "global resume" of the HC-to-USB interface (root hub), or
1841 * selective resume of one hub-to-device port
1842 */
1843 if (!udev->parent) {
1844 struct usb_bus *bus = udev->bus;
1845 if (bus && bus->op->hub_resume) {
1846 status = bus->op->hub_resume (bus);
1847 } else
1848 status = -EOPNOTSUPP;
1849 if (status == 0) {
1850 dev_dbg(&udev->dev, "usb resume\n");
1851 /* TRSMRCY = 10 msec */
1852 msleep(10);
1853 usb_set_device_state (udev, USB_STATE_CONFIGURED);
1854 udev->dev.power.power_state = PMSG_ON;
1855 status = hub_resume (udev
1856 ->actconfig->interface[0]);
1857 }
1858 } else if (udev->state == USB_STATE_SUSPENDED) {
1859 // NOTE this fails if parent is also suspended...
1860 status = hub_port_resume(hdev_to_hub(udev->parent),
1861 port1, udev);
1862 } else {
1863 status = 0;
1864 }
1865 if (status < 0) {
1866 dev_dbg(&udev->dev, "can't resume, status %d\n",
1867 status);
1868 }
1869
1870 usb_unlock_device(udev);
1871
1872 /* rebind drivers that had no suspend() */
1873 if (status == 0) {
1874 usb_lock_all_devices();
1875 bus_rescan_devices(&usb_bus_type);
1876 usb_unlock_all_devices();
1877 }
1878 return status;
1879}
1880
1881static int remote_wakeup(struct usb_device *udev)
1882{
1883 int status = 0;
1884
1885 /* don't repeat RESUME sequence if this device
1886 * was already woken up by some other task
1887 */
1888 down(&udev->serialize);
1889 if (udev->state == USB_STATE_SUSPENDED) {
1890 dev_dbg(&udev->dev, "RESUME (wakeup)\n");
1891 /* TRSMRCY = 10 msec */
1892 msleep(10);
1893 status = finish_port_resume(udev);
1894 }
1895 up(&udev->serialize);
1896 return status;
1897}
1898
1899static int hub_suspend(struct usb_interface *intf, pm_message_t state)
1900{
1901 struct usb_hub *hub = usb_get_intfdata (intf);
1902 struct usb_device *hdev = hub->hdev;
1903 unsigned port1;
1904 int status;
1905
1906 /* stop khubd and related activity */
1907 hub_quiesce(hub);
1908
1909 /* then suspend every port */
1910 for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1911 struct usb_device *udev;
1912
1913 udev = hdev->children [port1-1];
1914 if (!udev)
1915 continue;
1916 down(&udev->serialize);
1917 status = __usb_suspend_device(udev, port1, state);
1918 up(&udev->serialize);
1919 if (status < 0)
1920 dev_dbg(&intf->dev, "suspend port %d --> %d\n",
1921 port1, status);
1922 }
1923
1924 intf->dev.power.power_state = state;
1925 return 0;
1926}
1927
1928static int hub_resume(struct usb_interface *intf)
1929{
1930 struct usb_device *hdev = interface_to_usbdev(intf);
1931 struct usb_hub *hub = usb_get_intfdata (intf);
1932 unsigned port1;
1933 int status;
1934
1935 if (intf->dev.power.power_state == PM_SUSPEND_ON)
1936 return 0;
1937
1938 for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1939 struct usb_device *udev;
1940 u16 portstat, portchange;
1941
1942 udev = hdev->children [port1-1];
1943 status = hub_port_status(hub, port1, &portstat, &portchange);
1944 if (status == 0) {
1945 if (portchange & USB_PORT_STAT_C_SUSPEND) {
1946 clear_port_feature(hdev, port1,
1947 USB_PORT_FEAT_C_SUSPEND);
1948 portchange &= ~USB_PORT_STAT_C_SUSPEND;
1949 }
1950
1951 /* let khubd handle disconnects etc */
1952 if (portchange)
1953 continue;
1954 }
1955
1956 if (!udev || status < 0)
1957 continue;
1958 down (&udev->serialize);
1959 if (portstat & USB_PORT_STAT_SUSPEND)
1960 status = hub_port_resume(hub, port1, udev);
1961 else {
1962 status = finish_port_resume(udev);
1963 if (status < 0) {
1964 dev_dbg(&intf->dev, "resume port %d --> %d\n",
1965 port1, status);
1966 hub_port_logical_disconnect(hub, port1);
1967 }
1968 }
1969 up(&udev->serialize);
1970 }
1971 intf->dev.power.power_state = PMSG_ON;
1972
1973 hub->resume_root_hub = 0;
1974 hub_activate(hub);
1975 return 0;
1976}
1977
1978void usb_resume_root_hub(struct usb_device *hdev)
1979{
1980 struct usb_hub *hub = hdev_to_hub(hdev);
1981
1982 hub->resume_root_hub = 1;
1983 kick_khubd(hub);
1984}
1985
1986#else /* !CONFIG_USB_SUSPEND */
1987
1988int usb_suspend_device(struct usb_device *udev, pm_message_t state)
1989{
1990 return 0;
1991}
1992
1993int usb_resume_device(struct usb_device *udev)
1994{
1995 return 0;
1996}
1997
1998#define hub_suspend NULL
1999#define hub_resume NULL
2000#define remote_wakeup(x) 0
2001
2002#endif /* CONFIG_USB_SUSPEND */
2003
2004EXPORT_SYMBOL(usb_suspend_device);
2005EXPORT_SYMBOL(usb_resume_device);
2006
2007
2008
2009/* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2010 *
2011 * Between connect detection and reset signaling there must be a delay
2012 * of 100ms at least for debounce and power-settling. The corresponding
2013 * timer shall restart whenever the downstream port detects a disconnect.
2014 *
2015 * Apparently there are some bluetooth and irda-dongles and a number of
2016 * low-speed devices for which this debounce period may last over a second.
2017 * Not covered by the spec - but easy to deal with.
2018 *
2019 * This implementation uses a 1500ms total debounce timeout; if the
2020 * connection isn't stable by then it returns -ETIMEDOUT. It checks
2021 * every 25ms for transient disconnects. When the port status has been
2022 * unchanged for 100ms it returns the port status.
2023 */
2024
2025#define HUB_DEBOUNCE_TIMEOUT 1500
2026#define HUB_DEBOUNCE_STEP 25
2027#define HUB_DEBOUNCE_STABLE 100
2028
2029static int hub_port_debounce(struct usb_hub *hub, int port1)
2030{
2031 int ret;
2032 int total_time, stable_time = 0;
2033 u16 portchange, portstatus;
2034 unsigned connection = 0xffff;
2035
2036 for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2037 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2038 if (ret < 0)
2039 return ret;
2040
2041 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2042 (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2043 stable_time += HUB_DEBOUNCE_STEP;
2044 if (stable_time >= HUB_DEBOUNCE_STABLE)
2045 break;
2046 } else {
2047 stable_time = 0;
2048 connection = portstatus & USB_PORT_STAT_CONNECTION;
2049 }
2050
2051 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2052 clear_port_feature(hub->hdev, port1,
2053 USB_PORT_FEAT_C_CONNECTION);
2054 }
2055
2056 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2057 break;
2058 msleep(HUB_DEBOUNCE_STEP);
2059 }
2060
2061 dev_dbg (hub->intfdev,
2062 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2063 port1, total_time, stable_time, portstatus);
2064
2065 if (stable_time < HUB_DEBOUNCE_STABLE)
2066 return -ETIMEDOUT;
2067 return portstatus;
2068}
2069
2070static void ep0_reinit(struct usb_device *udev)
2071{
2072 usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2073 usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2074 udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2075}
2076
2077#define usb_sndaddr0pipe() (PIPE_CONTROL << 30)
2078#define usb_rcvaddr0pipe() ((PIPE_CONTROL << 30) | USB_DIR_IN)
2079
2080static int hub_set_address(struct usb_device *udev)
2081{
2082 int retval;
2083
2084 if (udev->devnum == 0)
2085 return -EINVAL;
2086 if (udev->state == USB_STATE_ADDRESS)
2087 return 0;
2088 if (udev->state != USB_STATE_DEFAULT)
2089 return -EINVAL;
2090 retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2091 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2092 NULL, 0, USB_CTRL_SET_TIMEOUT);
2093 if (retval == 0) {
2094 usb_set_device_state(udev, USB_STATE_ADDRESS);
2095 ep0_reinit(udev);
2096 }
2097 return retval;
2098}
2099
2100/* Reset device, (re)assign address, get device descriptor.
2101 * Device connection must be stable, no more debouncing needed.
2102 * Returns device in USB_STATE_ADDRESS, except on error.
2103 *
2104 * If this is called for an already-existing device (as part of
2105 * usb_reset_device), the caller must own the device lock. For a
2106 * newly detected device that is not accessible through any global
2107 * pointers, it's not necessary to lock the device.
2108 */
2109static int
2110hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2111 int retry_counter)
2112{
2113 static DECLARE_MUTEX(usb_address0_sem);
2114
2115 struct usb_device *hdev = hub->hdev;
2116 int i, j, retval;
2117 unsigned delay = HUB_SHORT_RESET_TIME;
2118 enum usb_device_speed oldspeed = udev->speed;
2119
2120 /* root hub ports have a slightly longer reset period
2121 * (from USB 2.0 spec, section 7.1.7.5)
2122 */
2123 if (!hdev->parent) {
2124 delay = HUB_ROOT_RESET_TIME;
2125 if (port1 == hdev->bus->otg_port)
2126 hdev->bus->b_hnp_enable = 0;
2127 }
2128
2129 /* Some low speed devices have problems with the quick delay, so */
2130 /* be a bit pessimistic with those devices. RHbug #23670 */
2131 if (oldspeed == USB_SPEED_LOW)
2132 delay = HUB_LONG_RESET_TIME;
2133
2134 down(&usb_address0_sem);
2135
2136 /* Reset the device; full speed may morph to high speed */
2137 retval = hub_port_reset(hub, port1, udev, delay);
2138 if (retval < 0) /* error or disconnect */
2139 goto fail;
2140 /* success, speed is known */
2141 retval = -ENODEV;
2142
2143 if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2144 dev_dbg(&udev->dev, "device reset changed speed!\n");
2145 goto fail;
2146 }
2147 oldspeed = udev->speed;
2148
2149 /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2150 * it's fixed size except for full speed devices.
2151 */
2152 switch (udev->speed) {
2153 case USB_SPEED_HIGH: /* fixed at 64 */
2154 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2155 break;
2156 case USB_SPEED_FULL: /* 8, 16, 32, or 64 */
2157 /* to determine the ep0 maxpacket size, try to read
2158 * the device descriptor to get bMaxPacketSize0 and
2159 * then correct our initial guess.
2160 */
2161 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2162 break;
2163 case USB_SPEED_LOW: /* fixed at 8 */
2164 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2165 break;
2166 default:
2167 goto fail;
2168 }
2169
2170 dev_info (&udev->dev,
2171 "%s %s speed USB device using %s and address %d\n",
2172 (udev->config) ? "reset" : "new",
2173 ({ char *speed; switch (udev->speed) {
2174 case USB_SPEED_LOW: speed = "low"; break;
2175 case USB_SPEED_FULL: speed = "full"; break;
2176 case USB_SPEED_HIGH: speed = "high"; break;
2177 default: speed = "?"; break;
2178 }; speed;}),
2179 udev->bus->controller->driver->name,
2180 udev->devnum);
2181
2182 /* Set up TT records, if needed */
2183 if (hdev->tt) {
2184 udev->tt = hdev->tt;
2185 udev->ttport = hdev->ttport;
2186 } else if (udev->speed != USB_SPEED_HIGH
2187 && hdev->speed == USB_SPEED_HIGH) {
2188 udev->tt = &hub->tt;
2189 udev->ttport = port1;
2190 }
2191
2192 /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2193 * Because device hardware and firmware is sometimes buggy in
2194 * this area, and this is how Linux has done it for ages.
2195 * Change it cautiously.
2196 *
2197 * NOTE: If USE_NEW_SCHEME() is true we will start by issuing
2198 * a 64-byte GET_DESCRIPTOR request. This is what Windows does,
2199 * so it may help with some non-standards-compliant devices.
2200 * Otherwise we start with SET_ADDRESS and then try to read the
2201 * first 8 bytes of the device descriptor to get the ep0 maxpacket
2202 * value.
2203 */
2204 for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2205 if (USE_NEW_SCHEME(retry_counter)) {
2206 struct usb_device_descriptor *buf;
2207 int r = 0;
2208
2209#define GET_DESCRIPTOR_BUFSIZE 64
2210 buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2211 if (!buf) {
2212 retval = -ENOMEM;
2213 continue;
2214 }
2215
2216 /* Use a short timeout the first time through,
2217 * so that recalcitrant full-speed devices with
2218 * 8- or 16-byte ep0-maxpackets won't slow things
2219 * down tremendously by NAKing the unexpectedly
2220 * early status stage. Also, retry on all errors;
2221 * some devices are flakey.
2222 */
2223 for (j = 0; j < 3; ++j) {
2224 buf->bMaxPacketSize0 = 0;
2225 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2226 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2227 USB_DT_DEVICE << 8, 0,
2228 buf, GET_DESCRIPTOR_BUFSIZE,
2229 (i ? USB_CTRL_GET_TIMEOUT : 1000));
2230 switch (buf->bMaxPacketSize0) {
2231 case 8: case 16: case 32: case 64:
2232 if (buf->bDescriptorType ==
2233 USB_DT_DEVICE) {
2234 r = 0;
2235 break;
2236 }
2237 /* FALL THROUGH */
2238 default:
2239 if (r == 0)
2240 r = -EPROTO;
2241 break;
2242 }
2243 if (r == 0)
2244 break;
2245 }
2246 udev->descriptor.bMaxPacketSize0 =
2247 buf->bMaxPacketSize0;
2248 kfree(buf);
2249
2250 retval = hub_port_reset(hub, port1, udev, delay);
2251 if (retval < 0) /* error or disconnect */
2252 goto fail;
2253 if (oldspeed != udev->speed) {
2254 dev_dbg(&udev->dev,
2255 "device reset changed speed!\n");
2256 retval = -ENODEV;
2257 goto fail;
2258 }
2259 if (r) {
2260 dev_err(&udev->dev, "device descriptor "
2261 "read/%s, error %d\n",
2262 "64", r);
2263 retval = -EMSGSIZE;
2264 continue;
2265 }
2266#undef GET_DESCRIPTOR_BUFSIZE
2267 }
2268
2269 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2270 retval = hub_set_address(udev);
2271 if (retval >= 0)
2272 break;
2273 msleep(200);
2274 }
2275 if (retval < 0) {
2276 dev_err(&udev->dev,
2277 "device not accepting address %d, error %d\n",
2278 udev->devnum, retval);
2279 goto fail;
2280 }
2281
2282 /* cope with hardware quirkiness:
2283 * - let SET_ADDRESS settle, some device hardware wants it
2284 * - read ep0 maxpacket even for high and low speed,
2285 */
2286 msleep(10);
2287 if (USE_NEW_SCHEME(retry_counter))
2288 break;
2289
2290 retval = usb_get_device_descriptor(udev, 8);
2291 if (retval < 8) {
2292 dev_err(&udev->dev, "device descriptor "
2293 "read/%s, error %d\n",
2294 "8", retval);
2295 if (retval >= 0)
2296 retval = -EMSGSIZE;
2297 } else {
2298 retval = 0;
2299 break;
2300 }
2301 }
2302 if (retval)
2303 goto fail;
2304
2305 i = udev->descriptor.bMaxPacketSize0;
2306 if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2307 if (udev->speed != USB_SPEED_FULL ||
2308 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2309 dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2310 retval = -EMSGSIZE;
2311 goto fail;
2312 }
2313 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2314 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2315 ep0_reinit(udev);
2316 }
2317
2318 retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2319 if (retval < (signed)sizeof(udev->descriptor)) {
2320 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2321 "all", retval);
2322 if (retval >= 0)
2323 retval = -ENOMSG;
2324 goto fail;
2325 }
2326
2327 retval = 0;
2328
2329fail:
2330 if (retval)
2331 hub_port_disable(hub, port1, 0);
2332 up(&usb_address0_sem);
2333 return retval;
2334}
2335
2336static void
2337check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2338{
2339 struct usb_qualifier_descriptor *qual;
2340 int status;
2341
2342 qual = kmalloc (sizeof *qual, SLAB_KERNEL);
2343 if (qual == NULL)
2344 return;
2345
2346 status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2347 qual, sizeof *qual);
2348 if (status == sizeof *qual) {
2349 dev_info(&udev->dev, "not running at top speed; "
2350 "connect to a high speed hub\n");
2351 /* hub LEDs are probably harder to miss than syslog */
2352 if (hub->has_indicators) {
2353 hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2354 schedule_work (&hub->leds);
2355 }
2356 }
2357 kfree (qual);
2358}
2359
2360static unsigned
2361hub_power_remaining (struct usb_hub *hub)
2362{
2363 struct usb_device *hdev = hub->hdev;
2364 int remaining;
2365 unsigned i;
2366
2367 remaining = hub->power_budget;
2368 if (!remaining) /* self-powered */
2369 return 0;
2370
2371 for (i = 0; i < hdev->maxchild; i++) {
2372 struct usb_device *udev = hdev->children[i];
2373 int delta, ceiling;
2374
2375 if (!udev)
2376 continue;
2377
2378 /* 100mA per-port ceiling, or 8mA for OTG ports */
2379 if (i != (udev->bus->otg_port - 1) || hdev->parent)
2380 ceiling = 50;
2381 else
2382 ceiling = 4;
2383
2384 if (udev->actconfig)
2385 delta = udev->actconfig->desc.bMaxPower;
2386 else
2387 delta = ceiling;
2388 // dev_dbg(&udev->dev, "budgeted %dmA\n", 2 * delta);
2389 if (delta > ceiling)
2390 dev_warn(&udev->dev, "%dmA over %dmA budget!\n",
2391 2 * (delta - ceiling), 2 * ceiling);
2392 remaining -= delta;
2393 }
2394 if (remaining < 0) {
2395 dev_warn(hub->intfdev,
2396 "%dmA over power budget!\n",
2397 -2 * remaining);
2398 remaining = 0;
2399 }
2400 return remaining;
2401}
2402
2403/* Handle physical or logical connection change events.
2404 * This routine is called when:
2405 * a port connection-change occurs;
2406 * a port enable-change occurs (often caused by EMI);
2407 * usb_reset_device() encounters changed descriptors (as from
2408 * a firmware download)
2409 * caller already locked the hub
2410 */
2411static void hub_port_connect_change(struct usb_hub *hub, int port1,
2412 u16 portstatus, u16 portchange)
2413{
2414 struct usb_device *hdev = hub->hdev;
2415 struct device *hub_dev = hub->intfdev;
2416 int status, i;
2417
2418 dev_dbg (hub_dev,
2419 "port %d, status %04x, change %04x, %s\n",
2420 port1, portstatus, portchange, portspeed (portstatus));
2421
2422 if (hub->has_indicators) {
2423 set_port_led(hub, port1, HUB_LED_AUTO);
2424 hub->indicator[port1-1] = INDICATOR_AUTO;
2425 }
2426
2427 /* Disconnect any existing devices under this port */
2428 if (hdev->children[port1-1])
2429 usb_disconnect(&hdev->children[port1-1]);
2430 clear_bit(port1, hub->change_bits);
2431
2432#ifdef CONFIG_USB_OTG
2433 /* during HNP, don't repeat the debounce */
2434 if (hdev->bus->is_b_host)
2435 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2436#endif
2437
2438 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2439 status = hub_port_debounce(hub, port1);
2440 if (status < 0) {
2441 dev_err (hub_dev,
2442 "connect-debounce failed, port %d disabled\n",
2443 port1);
2444 goto done;
2445 }
2446 portstatus = status;
2447 }
2448
2449 /* Return now if nothing is connected */
2450 if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2451
2452 /* maybe switch power back on (e.g. root hub was reset) */
2453 if ((hub->descriptor->wHubCharacteristics
2454 & HUB_CHAR_LPSM) < 2
2455 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2456 set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2457
2458 if (portstatus & USB_PORT_STAT_ENABLE)
2459 goto done;
2460 return;
2461 }
2462
2463#ifdef CONFIG_USB_SUSPEND
2464 /* If something is connected, but the port is suspended, wake it up. */
2465 if (portstatus & USB_PORT_STAT_SUSPEND) {
2466 status = hub_port_resume(hub, port1, NULL);
2467 if (status < 0) {
2468 dev_dbg(hub_dev,
2469 "can't clear suspend on port %d; %d\n",
2470 port1, status);
2471 goto done;
2472 }
2473 }
2474#endif
2475
2476 for (i = 0; i < SET_CONFIG_TRIES; i++) {
2477 struct usb_device *udev;
2478
2479 /* reallocate for each attempt, since references
2480 * to the previous one can escape in various ways
2481 */
2482 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2483 if (!udev) {
2484 dev_err (hub_dev,
2485 "couldn't allocate port %d usb_device\n",
2486 port1);
2487 goto done;
2488 }
2489
2490 usb_set_device_state(udev, USB_STATE_POWERED);
2491 udev->speed = USB_SPEED_UNKNOWN;
2492
2493 /* set the address */
2494 choose_address(udev);
2495 if (udev->devnum <= 0) {
2496 status = -ENOTCONN; /* Don't retry */
2497 goto loop;
2498 }
2499
2500 /* reset and get descriptor */
2501 status = hub_port_init(hub, udev, port1, i);
2502 if (status < 0)
2503 goto loop;
2504
2505 /* consecutive bus-powered hubs aren't reliable; they can
2506 * violate the voltage drop budget. if the new child has
2507 * a "powered" LED, users should notice we didn't enable it
2508 * (without reading syslog), even without per-port LEDs
2509 * on the parent.
2510 */
2511 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2512 && hub->power_budget) {
2513 u16 devstat;
2514
2515 status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2516 &devstat);
2517 if (status < 0) {
2518 dev_dbg(&udev->dev, "get status %d ?\n", status);
2519 goto loop_disable;
2520 }
2521 cpu_to_le16s(&devstat);
2522 if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2523 dev_err(&udev->dev,
2524 "can't connect bus-powered hub "
2525 "to this port\n");
2526 if (hub->has_indicators) {
2527 hub->indicator[port1-1] =
2528 INDICATOR_AMBER_BLINK;
2529 schedule_work (&hub->leds);
2530 }
2531 status = -ENOTCONN; /* Don't retry */
2532 goto loop_disable;
2533 }
2534 }
2535
2536 /* check for devices running slower than they could */
2537 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2538 && udev->speed == USB_SPEED_FULL
2539 && highspeed_hubs != 0)
2540 check_highspeed (hub, udev, port1);
2541
2542 /* Store the parent's children[] pointer. At this point
2543 * udev becomes globally accessible, although presumably
2544 * no one will look at it until hdev is unlocked.
2545 */
2546 down (&udev->serialize);
2547 status = 0;
2548
2549 /* We mustn't add new devices if the parent hub has
2550 * been disconnected; we would race with the
2551 * recursively_mark_NOTATTACHED() routine.
2552 */
2553 spin_lock_irq(&device_state_lock);
2554 if (hdev->state == USB_STATE_NOTATTACHED)
2555 status = -ENOTCONN;
2556 else
2557 hdev->children[port1-1] = udev;
2558 spin_unlock_irq(&device_state_lock);
2559
2560 /* Run it through the hoops (find a driver, etc) */
2561 if (!status) {
2562 status = usb_new_device(udev);
2563 if (status) {
2564 spin_lock_irq(&device_state_lock);
2565 hdev->children[port1-1] = NULL;
2566 spin_unlock_irq(&device_state_lock);
2567 }
2568 }
2569
2570 up (&udev->serialize);
2571 if (status)
2572 goto loop_disable;
2573
2574 status = hub_power_remaining(hub);
2575 if (status)
2576 dev_dbg(hub_dev,
2577 "%dmA power budget left\n",
2578 2 * status);
2579
2580 return;
2581
2582loop_disable:
2583 hub_port_disable(hub, port1, 1);
2584loop:
2585 ep0_reinit(udev);
2586 release_address(udev);
2587 usb_put_dev(udev);
2588 if (status == -ENOTCONN)
2589 break;
2590 }
2591
2592done:
2593 hub_port_disable(hub, port1, 1);
2594}
2595
2596static void hub_events(void)
2597{
2598 struct list_head *tmp;
2599 struct usb_device *hdev;
2600 struct usb_interface *intf;
2601 struct usb_hub *hub;
2602 struct device *hub_dev;
2603 u16 hubstatus;
2604 u16 hubchange;
2605 u16 portstatus;
2606 u16 portchange;
2607 int i, ret;
2608 int connect_change;
2609
2610 /*
2611 * We restart the list every time to avoid a deadlock with
2612 * deleting hubs downstream from this one. This should be
2613 * safe since we delete the hub from the event list.
2614 * Not the most efficient, but avoids deadlocks.
2615 */
2616 while (1) {
2617
2618 /* Grab the first entry at the beginning of the list */
2619 spin_lock_irq(&hub_event_lock);
2620 if (list_empty(&hub_event_list)) {
2621 spin_unlock_irq(&hub_event_lock);
2622 break;
2623 }
2624
2625 tmp = hub_event_list.next;
2626 list_del_init(tmp);
2627
2628 hub = list_entry(tmp, struct usb_hub, event_list);
2629 hdev = hub->hdev;
2630 intf = to_usb_interface(hub->intfdev);
2631 hub_dev = &intf->dev;
2632
2633 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
2634 hdev->state, hub->descriptor
2635 ? hub->descriptor->bNbrPorts
2636 : 0,
2637 /* NOTE: expects max 15 ports... */
2638 (u16) hub->change_bits[0],
2639 (u16) hub->event_bits[0]);
2640
2641 usb_get_intf(intf);
2642 i = hub->resume_root_hub;
2643 spin_unlock_irq(&hub_event_lock);
2644
2645 /* Is this is a root hub wanting to be resumed? */
2646 if (i)
2647 usb_resume_device(hdev);
2648
2649 /* Lock the device, then check to see if we were
2650 * disconnected while waiting for the lock to succeed. */
2651 if (locktree(hdev) < 0) {
2652 usb_put_intf(intf);
2653 continue;
2654 }
2655 if (hub != usb_get_intfdata(intf))
2656 goto loop;
2657
2658 /* If the hub has died, clean up after it */
2659 if (hdev->state == USB_STATE_NOTATTACHED) {
2660 hub_pre_reset(hub);
2661 goto loop;
2662 }
2663
2664 /* If this is an inactive or suspended hub, do nothing */
2665 if (hub->quiescing)
2666 goto loop;
2667
2668 if (hub->error) {
2669 dev_dbg (hub_dev, "resetting for error %d\n",
2670 hub->error);
2671
2672 ret = usb_reset_device(hdev);
2673 if (ret) {
2674 dev_dbg (hub_dev,
2675 "error resetting hub: %d\n", ret);
2676 goto loop;
2677 }
2678
2679 hub->nerrors = 0;
2680 hub->error = 0;
2681 }
2682
2683 /* deal with port status changes */
2684 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2685 if (test_bit(i, hub->busy_bits))
2686 continue;
2687 connect_change = test_bit(i, hub->change_bits);
2688 if (!test_and_clear_bit(i, hub->event_bits) &&
2689 !connect_change && !hub->activating)
2690 continue;
2691
2692 ret = hub_port_status(hub, i,
2693 &portstatus, &portchange);
2694 if (ret < 0)
2695 continue;
2696
2697 if (hub->activating && !hdev->children[i-1] &&
2698 (portstatus &
2699 USB_PORT_STAT_CONNECTION))
2700 connect_change = 1;
2701
2702 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2703 clear_port_feature(hdev, i,
2704 USB_PORT_FEAT_C_CONNECTION);
2705 connect_change = 1;
2706 }
2707
2708 if (portchange & USB_PORT_STAT_C_ENABLE) {
2709 if (!connect_change)
2710 dev_dbg (hub_dev,
2711 "port %d enable change, "
2712 "status %08x\n",
2713 i, portstatus);
2714 clear_port_feature(hdev, i,
2715 USB_PORT_FEAT_C_ENABLE);
2716
2717 /*
2718 * EM interference sometimes causes badly
2719 * shielded USB devices to be shutdown by
2720 * the hub, this hack enables them again.
2721 * Works at least with mouse driver.
2722 */
2723 if (!(portstatus & USB_PORT_STAT_ENABLE)
2724 && !connect_change
2725 && hdev->children[i-1]) {
2726 dev_err (hub_dev,
2727 "port %i "
2728 "disabled by hub (EMI?), "
2729 "re-enabling...\n",
2730 i);
2731 connect_change = 1;
2732 }
2733 }
2734
2735 if (portchange & USB_PORT_STAT_C_SUSPEND) {
2736 clear_port_feature(hdev, i,
2737 USB_PORT_FEAT_C_SUSPEND);
2738 if (hdev->children[i-1]) {
2739 ret = remote_wakeup(hdev->
2740 children[i-1]);
2741 if (ret < 0)
2742 connect_change = 1;
2743 } else {
2744 ret = -ENODEV;
2745 hub_port_disable(hub, i, 1);
2746 }
2747 dev_dbg (hub_dev,
2748 "resume on port %d, status %d\n",
2749 i, ret);
2750 }
2751
2752 if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2753 dev_err (hub_dev,
2754 "over-current change on port %d\n",
2755 i);
2756 clear_port_feature(hdev, i,
2757 USB_PORT_FEAT_C_OVER_CURRENT);
2758 hub_power_on(hub);
2759 }
2760
2761 if (portchange & USB_PORT_STAT_C_RESET) {
2762 dev_dbg (hub_dev,
2763 "reset change on port %d\n",
2764 i);
2765 clear_port_feature(hdev, i,
2766 USB_PORT_FEAT_C_RESET);
2767 }
2768
2769 if (connect_change)
2770 hub_port_connect_change(hub, i,
2771 portstatus, portchange);
2772 } /* end for i */
2773
2774 /* deal with hub status changes */
2775 if (test_and_clear_bit(0, hub->event_bits) == 0)
2776 ; /* do nothing */
2777 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2778 dev_err (hub_dev, "get_hub_status failed\n");
2779 else {
2780 if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2781 dev_dbg (hub_dev, "power change\n");
2782 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2783 }
2784 if (hubchange & HUB_CHANGE_OVERCURRENT) {
2785 dev_dbg (hub_dev, "overcurrent change\n");
2786 msleep(500); /* Cool down */
2787 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2788 hub_power_on(hub);
2789 }
2790 }
2791
2792 hub->activating = 0;
2793
2794loop:
2795 usb_unlock_device(hdev);
2796 usb_put_intf(intf);
2797
2798 } /* end while (1) */
2799}
2800
2801static int hub_thread(void *__unused)
2802{
2803 /*
2804 * This thread doesn't need any user-level access,
2805 * so get rid of all our resources
2806 */
2807
2808 daemonize("khubd");
2809 allow_signal(SIGKILL);
2810
2811 /* Send me a signal to get me die (for debugging) */
2812 do {
2813 hub_events();
2814 wait_event_interruptible(khubd_wait, !list_empty(&hub_event_list));
2815 try_to_freeze(PF_FREEZE);
2816 } while (!signal_pending(current));
2817
2818 pr_debug ("%s: khubd exiting\n", usbcore_name);
2819 complete_and_exit(&khubd_exited, 0);
2820}
2821
2822static struct usb_device_id hub_id_table [] = {
2823 { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2824 .bDeviceClass = USB_CLASS_HUB},
2825 { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2826 .bInterfaceClass = USB_CLASS_HUB},
2827 { } /* Terminating entry */
2828};
2829
2830MODULE_DEVICE_TABLE (usb, hub_id_table);
2831
2832static struct usb_driver hub_driver = {
2833 .owner = THIS_MODULE,
2834 .name = "hub",
2835 .probe = hub_probe,
2836 .disconnect = hub_disconnect,
2837 .suspend = hub_suspend,
2838 .resume = hub_resume,
2839 .ioctl = hub_ioctl,
2840 .id_table = hub_id_table,
2841};
2842
2843int usb_hub_init(void)
2844{
2845 pid_t pid;
2846
2847 if (usb_register(&hub_driver) < 0) {
2848 printk(KERN_ERR "%s: can't register hub driver\n",
2849 usbcore_name);
2850 return -1;
2851 }
2852
2853 pid = kernel_thread(hub_thread, NULL, CLONE_KERNEL);
2854 if (pid >= 0) {
2855 khubd_pid = pid;
2856
2857 return 0;
2858 }
2859
2860 /* Fall through if kernel_thread failed */
2861 usb_deregister(&hub_driver);
2862 printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2863
2864 return -1;
2865}
2866
2867void usb_hub_cleanup(void)
2868{
2869 int ret;
2870
2871 /* Kill the thread */
2872 ret = kill_proc(khubd_pid, SIGKILL, 1);
2873
2874 wait_for_completion(&khubd_exited);
2875
2876 /*
2877 * Hub resources are freed for us by usb_deregister. It calls
2878 * usb_driver_purge on every device which in turn calls that
2879 * devices disconnect function if it is using this driver.
2880 * The hub_disconnect function takes care of releasing the
2881 * individual hub resources. -greg
2882 */
2883 usb_deregister(&hub_driver);
2884} /* usb_hub_cleanup() */
2885
2886
2887static int config_descriptors_changed(struct usb_device *udev)
2888{
2889 unsigned index;
2890 unsigned len = 0;
2891 struct usb_config_descriptor *buf;
2892
2893 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2894 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2895 len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2896 }
2897 buf = kmalloc (len, SLAB_KERNEL);
2898 if (buf == NULL) {
2899 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2900 /* assume the worst */
2901 return 1;
2902 }
2903 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2904 int length;
2905 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2906
2907 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2908 old_length);
2909 if (length < old_length) {
2910 dev_dbg(&udev->dev, "config index %d, error %d\n",
2911 index, length);
2912 break;
2913 }
2914 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2915 != 0) {
2916 dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2917 index, buf->bConfigurationValue);
2918 break;
2919 }
2920 }
2921 kfree(buf);
2922 return index != udev->descriptor.bNumConfigurations;
2923}
2924
2925/**
2926 * usb_reset_device - perform a USB port reset to reinitialize a device
2927 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2928 *
2929 * WARNING - don't reset any device unless drivers for all of its
2930 * interfaces are expecting that reset! Maybe some driver->reset()
2931 * method should eventually help ensure sufficient cooperation.
2932 *
2933 * Do a port reset, reassign the device's address, and establish its
2934 * former operating configuration. If the reset fails, or the device's
2935 * descriptors change from their values before the reset, or the original
2936 * configuration and altsettings cannot be restored, a flag will be set
2937 * telling khubd to pretend the device has been disconnected and then
2938 * re-connected. All drivers will be unbound, and the device will be
2939 * re-enumerated and probed all over again.
2940 *
2941 * Returns 0 if the reset succeeded, -ENODEV if the device has been
2942 * flagged for logical disconnection, or some other negative error code
2943 * if the reset wasn't even attempted.
2944 *
2945 * The caller must own the device lock. For example, it's safe to use
2946 * this from a driver probe() routine after downloading new firmware.
2947 * For calls that might not occur during probe(), drivers should lock
2948 * the device using usb_lock_device_for_reset().
2949 */
2950int usb_reset_device(struct usb_device *udev)
2951{
2952 struct usb_device *parent_hdev = udev->parent;
2953 struct usb_hub *parent_hub;
2954 struct usb_device_descriptor descriptor = udev->descriptor;
2955 struct usb_hub *hub = NULL;
2956 int i, ret = 0, port1 = -1;
2957
2958 if (udev->state == USB_STATE_NOTATTACHED ||
2959 udev->state == USB_STATE_SUSPENDED) {
2960 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2961 udev->state);
2962 return -EINVAL;
2963 }
2964
2965 if (!parent_hdev) {
2966 /* this requires hcd-specific logic; see OHCI hc_restart() */
2967 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2968 return -EISDIR;
2969 }
2970
2971 for (i = 0; i < parent_hdev->maxchild; i++)
2972 if (parent_hdev->children[i] == udev) {
2973 port1 = i + 1;
2974 break;
2975 }
2976
2977 if (port1 < 0) {
2978 /* If this ever happens, it's very bad */
2979 dev_err(&udev->dev, "Can't locate device's port!\n");
2980 return -ENOENT;
2981 }
2982 parent_hub = hdev_to_hub(parent_hdev);
2983
2984 /* If we're resetting an active hub, take some special actions */
2985 if (udev->actconfig &&
2986 udev->actconfig->interface[0]->dev.driver ==
2987 &hub_driver.driver &&
2988 (hub = hdev_to_hub(udev)) != NULL) {
2989 hub_pre_reset(hub);
2990 }
2991
2992 set_bit(port1, parent_hub->busy_bits);
2993 for (i = 0; i < SET_CONFIG_TRIES; ++i) {
2994
2995 /* ep0 maxpacket size may change; let the HCD know about it.
2996 * Other endpoints will be handled by re-enumeration. */
2997 ep0_reinit(udev);
2998 ret = hub_port_init(parent_hub, udev, port1, i);
2999 if (ret >= 0)
3000 break;
3001 }
3002 clear_bit(port1, parent_hub->busy_bits);
3003 if (ret < 0)
3004 goto re_enumerate;
3005
3006 /* Device might have changed firmware (DFU or similar) */
3007 if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
3008 || config_descriptors_changed (udev)) {
3009 dev_info(&udev->dev, "device firmware changed\n");
3010 udev->descriptor = descriptor; /* for disconnect() calls */
3011 goto re_enumerate;
3012 }
3013
3014 if (!udev->actconfig)
3015 goto done;
3016
3017 ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3018 USB_REQ_SET_CONFIGURATION, 0,
3019 udev->actconfig->desc.bConfigurationValue, 0,
3020 NULL, 0, USB_CTRL_SET_TIMEOUT);
3021 if (ret < 0) {
3022 dev_err(&udev->dev,
3023 "can't restore configuration #%d (error=%d)\n",
3024 udev->actconfig->desc.bConfigurationValue, ret);
3025 goto re_enumerate;
3026 }
3027 usb_set_device_state(udev, USB_STATE_CONFIGURED);
3028
3029 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3030 struct usb_interface *intf = udev->actconfig->interface[i];
3031 struct usb_interface_descriptor *desc;
3032
3033 /* set_interface resets host side toggle even
3034 * for altsetting zero. the interface may have no driver.
3035 */
3036 desc = &intf->cur_altsetting->desc;
3037 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3038 desc->bAlternateSetting);
3039 if (ret < 0) {
3040 dev_err(&udev->dev, "failed to restore interface %d "
3041 "altsetting %d (error=%d)\n",
3042 desc->bInterfaceNumber,
3043 desc->bAlternateSetting,
3044 ret);
3045 goto re_enumerate;
3046 }
3047 }
3048
3049done:
3050 if (hub)
3051 hub_post_reset(hub);
3052 return 0;
3053
3054re_enumerate:
3055 hub_port_logical_disconnect(parent_hub, port1);
3056 return -ENODEV;
3057}
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-10 19:32:36 -0500