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)
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/smp_lock.h>
20 #include <linux/ioctl.h>
21 #include <linux/usb.h>
22 #include <linux/usbdevice_fs.h>
23 #include <linux/kthread.h>
24 #include <linux/mutex.h>
26 #include <asm/semaphore.h>
27 #include <asm/uaccess.h>
28 #include <asm/byteorder.h>
34 /* Protect struct usb_device->state and ->children members
35 * Note: Both are also protected by ->dev.sem, except that ->state can
36 * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
37 static DEFINE_SPINLOCK(device_state_lock);
39 /* khubd's worklist and its lock */
40 static DEFINE_SPINLOCK(hub_event_lock);
41 static LIST_HEAD(hub_event_list); /* List of hubs needing servicing */
44 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
46 static struct task_struct *khubd_task;
48 /* cycle leds on hubs that aren't blinking for attention */
49 static int blinkenlights = 0;
50 module_param (blinkenlights, bool, S_IRUGO);
51 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
54 * As of 2.6.10 we introduce a new USB device initialization scheme which
55 * closely resembles the way Windows works. Hopefully it will be compatible
56 * with a wider range of devices than the old scheme. However some previously
57 * working devices may start giving rise to "device not accepting address"
58 * errors; if that happens the user can try the old scheme by adjusting the
59 * following module parameters.
61 * For maximum flexibility there are two boolean parameters to control the
62 * hub driver's behavior. On the first initialization attempt, if the
63 * "old_scheme_first" parameter is set then the old scheme will be used,
64 * otherwise the new scheme is used. If that fails and "use_both_schemes"
65 * is set, then the driver will make another attempt, using the other scheme.
67 static int old_scheme_first = 0;
68 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
69 MODULE_PARM_DESC(old_scheme_first,
70 "start with the old device initialization scheme");
72 static int use_both_schemes = 1;
73 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
74 MODULE_PARM_DESC(use_both_schemes,
75 "try the other device initialization scheme if the "
80 static inline char *portspeed (int portstatus)
82 if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
84 else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
91 /* Note that hdev or one of its children must be locked! */
92 static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
94 return usb_get_intfdata(hdev->actconfig->interface[0]);
97 /* USB 2.0 spec Section 11.24.4.5 */
98 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
102 for (i = 0; i < 3; i++) {
103 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
104 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
105 USB_DT_HUB << 8, 0, data, size,
106 USB_CTRL_GET_TIMEOUT);
107 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
114 * USB 2.0 spec Section 11.24.2.1
116 static int clear_hub_feature(struct usb_device *hdev, int feature)
118 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
119 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
123 * USB 2.0 spec Section 11.24.2.2
125 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
127 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
128 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
133 * USB 2.0 spec Section 11.24.2.13
135 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
137 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
138 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
143 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
144 * for info about using port indicators
146 static void set_port_led(
152 int status = set_port_feature(hub->hdev, (selector << 8) | port1,
153 USB_PORT_FEAT_INDICATOR);
155 dev_dbg (hub->intfdev,
156 "port %d indicator %s status %d\n",
158 ({ char *s; switch (selector) {
159 case HUB_LED_AMBER: s = "amber"; break;
160 case HUB_LED_GREEN: s = "green"; break;
161 case HUB_LED_OFF: s = "off"; break;
162 case HUB_LED_AUTO: s = "auto"; break;
163 default: s = "??"; break;
168 #define LED_CYCLE_PERIOD ((2*HZ)/3)
170 static void led_work (struct work_struct *work)
172 struct usb_hub *hub =
173 container_of(work, struct usb_hub, leds.work);
174 struct usb_device *hdev = hub->hdev;
176 unsigned changed = 0;
179 if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
182 for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
183 unsigned selector, mode;
185 /* 30%-50% duty cycle */
187 switch (hub->indicator[i]) {
189 case INDICATOR_CYCLE:
191 selector = HUB_LED_AUTO;
192 mode = INDICATOR_AUTO;
194 /* blinking green = sw attention */
195 case INDICATOR_GREEN_BLINK:
196 selector = HUB_LED_GREEN;
197 mode = INDICATOR_GREEN_BLINK_OFF;
199 case INDICATOR_GREEN_BLINK_OFF:
200 selector = HUB_LED_OFF;
201 mode = INDICATOR_GREEN_BLINK;
203 /* blinking amber = hw attention */
204 case INDICATOR_AMBER_BLINK:
205 selector = HUB_LED_AMBER;
206 mode = INDICATOR_AMBER_BLINK_OFF;
208 case INDICATOR_AMBER_BLINK_OFF:
209 selector = HUB_LED_OFF;
210 mode = INDICATOR_AMBER_BLINK;
212 /* blink green/amber = reserved */
213 case INDICATOR_ALT_BLINK:
214 selector = HUB_LED_GREEN;
215 mode = INDICATOR_ALT_BLINK_OFF;
217 case INDICATOR_ALT_BLINK_OFF:
218 selector = HUB_LED_AMBER;
219 mode = INDICATOR_ALT_BLINK;
224 if (selector != HUB_LED_AUTO)
226 set_port_led(hub, i + 1, selector);
227 hub->indicator[i] = mode;
229 if (!changed && blinkenlights) {
231 cursor %= hub->descriptor->bNbrPorts;
232 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
233 hub->indicator[cursor] = INDICATOR_CYCLE;
237 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
240 /* use a short timeout for hub/port status fetches */
241 #define USB_STS_TIMEOUT 1000
242 #define USB_STS_RETRIES 5
245 * USB 2.0 spec Section 11.24.2.6
247 static int get_hub_status(struct usb_device *hdev,
248 struct usb_hub_status *data)
250 int i, status = -ETIMEDOUT;
252 for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
253 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
254 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
255 data, sizeof(*data), USB_STS_TIMEOUT);
261 * USB 2.0 spec Section 11.24.2.7
263 static int get_port_status(struct usb_device *hdev, int port1,
264 struct usb_port_status *data)
266 int i, status = -ETIMEDOUT;
268 for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
269 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
270 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
271 data, sizeof(*data), USB_STS_TIMEOUT);
276 static void kick_khubd(struct usb_hub *hub)
280 spin_lock_irqsave(&hub_event_lock, flags);
281 if (list_empty(&hub->event_list)) {
282 list_add_tail(&hub->event_list, &hub_event_list);
283 wake_up(&khubd_wait);
285 spin_unlock_irqrestore(&hub_event_lock, flags);
288 void usb_kick_khubd(struct usb_device *hdev)
290 kick_khubd(hdev_to_hub(hdev));
294 /* completion function, fires on port status changes and various faults */
295 static void hub_irq(struct urb *urb)
297 struct usb_hub *hub = urb->context;
302 switch (urb->status) {
303 case -ENOENT: /* synchronous unlink */
304 case -ECONNRESET: /* async unlink */
305 case -ESHUTDOWN: /* hardware going away */
308 default: /* presumably an error */
309 /* Cause a hub reset after 10 consecutive errors */
310 dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
311 if ((++hub->nerrors < 10) || hub->error)
313 hub->error = urb->status;
316 /* let khubd handle things */
317 case 0: /* we got data: port status changed */
319 for (i = 0; i < urb->actual_length; ++i)
320 bits |= ((unsigned long) ((*hub->buffer)[i]))
322 hub->event_bits[0] = bits;
328 /* Something happened, let khubd figure it out */
335 if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
336 && status != -ENODEV && status != -EPERM)
337 dev_err (hub->intfdev, "resubmit --> %d\n", status);
340 /* USB 2.0 spec Section 11.24.2.3 */
342 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
344 return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
345 HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
350 * enumeration blocks khubd for a long time. we use keventd instead, since
351 * long blocking there is the exception, not the rule. accordingly, HCDs
352 * talking to TTs must queue control transfers (not just bulk and iso), so
353 * both can talk to the same hub concurrently.
355 static void hub_tt_kevent (struct work_struct *work)
357 struct usb_hub *hub =
358 container_of(work, struct usb_hub, tt.kevent);
361 spin_lock_irqsave (&hub->tt.lock, flags);
362 while (!list_empty (&hub->tt.clear_list)) {
363 struct list_head *temp;
364 struct usb_tt_clear *clear;
365 struct usb_device *hdev = hub->hdev;
368 temp = hub->tt.clear_list.next;
369 clear = list_entry (temp, struct usb_tt_clear, clear_list);
370 list_del (&clear->clear_list);
372 /* drop lock so HCD can concurrently report other TT errors */
373 spin_unlock_irqrestore (&hub->tt.lock, flags);
374 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
375 spin_lock_irqsave (&hub->tt.lock, flags);
379 "clear tt %d (%04x) error %d\n",
380 clear->tt, clear->devinfo, status);
383 spin_unlock_irqrestore (&hub->tt.lock, flags);
387 * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
388 * @udev: the device whose split transaction failed
389 * @pipe: identifies the endpoint of the failed transaction
391 * High speed HCDs use this to tell the hub driver that some split control or
392 * bulk transaction failed in a way that requires clearing internal state of
393 * a transaction translator. This is normally detected (and reported) from
396 * It may not be possible for that hub to handle additional full (or low)
397 * speed transactions until that state is fully cleared out.
399 void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
401 struct usb_tt *tt = udev->tt;
403 struct usb_tt_clear *clear;
405 /* we've got to cope with an arbitrary number of pending TT clears,
406 * since each TT has "at least two" buffers that can need it (and
407 * there can be many TTs per hub). even if they're uncommon.
409 if ((clear = kmalloc (sizeof *clear, SLAB_ATOMIC)) == NULL) {
410 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
411 /* FIXME recover somehow ... RESET_TT? */
415 /* info that CLEAR_TT_BUFFER needs */
416 clear->tt = tt->multi ? udev->ttport : 1;
417 clear->devinfo = usb_pipeendpoint (pipe);
418 clear->devinfo |= udev->devnum << 4;
419 clear->devinfo |= usb_pipecontrol (pipe)
420 ? (USB_ENDPOINT_XFER_CONTROL << 11)
421 : (USB_ENDPOINT_XFER_BULK << 11);
422 if (usb_pipein (pipe))
423 clear->devinfo |= 1 << 15;
425 /* tell keventd to clear state for this TT */
426 spin_lock_irqsave (&tt->lock, flags);
427 list_add_tail (&clear->clear_list, &tt->clear_list);
428 schedule_work (&tt->kevent);
429 spin_unlock_irqrestore (&tt->lock, flags);
432 static void hub_power_on(struct usb_hub *hub)
435 unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
436 u16 wHubCharacteristics =
437 le16_to_cpu(hub->descriptor->wHubCharacteristics);
439 /* Enable power on each port. Some hubs have reserved values
440 * of LPSM (> 2) in their descriptors, even though they are
441 * USB 2.0 hubs. Some hubs do not implement port-power switching
442 * but only emulate it. In all cases, the ports won't work
443 * unless we send these messages to the hub.
445 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
446 dev_dbg(hub->intfdev, "enabling power on all ports\n");
448 dev_dbg(hub->intfdev, "trying to enable port power on "
449 "non-switchable hub\n");
450 for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
451 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
453 /* Wait at least 100 msec for power to become stable */
454 msleep(max(pgood_delay, (unsigned) 100));
457 static void hub_quiesce(struct usb_hub *hub)
459 /* (nonblocking) khubd and related activity won't re-trigger */
462 hub->resume_root_hub = 0;
464 /* (blocking) stop khubd and related activity */
465 usb_kill_urb(hub->urb);
466 if (hub->has_indicators)
467 cancel_delayed_work(&hub->leds);
468 if (hub->has_indicators || hub->tt.hub)
469 flush_scheduled_work();
472 static void hub_activate(struct usb_hub *hub)
478 hub->resume_root_hub = 0;
479 status = usb_submit_urb(hub->urb, GFP_NOIO);
481 dev_err(hub->intfdev, "activate --> %d\n", status);
482 if (hub->has_indicators && blinkenlights)
483 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
485 /* scan all ports ASAP */
489 static int hub_hub_status(struct usb_hub *hub,
490 u16 *status, u16 *change)
494 ret = get_hub_status(hub->hdev, &hub->status->hub);
496 dev_err (hub->intfdev,
497 "%s failed (err = %d)\n", __FUNCTION__, ret);
499 *status = le16_to_cpu(hub->status->hub.wHubStatus);
500 *change = le16_to_cpu(hub->status->hub.wHubChange);
506 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
508 struct usb_device *hdev = hub->hdev;
511 if (hdev->children[port1-1] && set_state) {
512 usb_set_device_state(hdev->children[port1-1],
513 USB_STATE_NOTATTACHED);
515 ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
517 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
524 /* caller has locked the hub device */
525 static void hub_pre_reset(struct usb_interface *intf)
527 struct usb_hub *hub = usb_get_intfdata(intf);
528 struct usb_device *hdev = hub->hdev;
531 for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
532 if (hdev->children[port1 - 1]) {
533 usb_disconnect(&hdev->children[port1 - 1]);
535 hub_port_disable(hub, port1, 0);
541 /* caller has locked the hub device */
542 static void hub_post_reset(struct usb_interface *intf)
544 struct usb_hub *hub = usb_get_intfdata(intf);
551 static int hub_configure(struct usb_hub *hub,
552 struct usb_endpoint_descriptor *endpoint)
554 struct usb_device *hdev = hub->hdev;
555 struct device *hub_dev = hub->intfdev;
556 u16 hubstatus, hubchange;
557 u16 wHubCharacteristics;
562 hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
565 message = "can't allocate hub irq buffer";
570 hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
572 message = "can't kmalloc hub status buffer";
577 hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
578 if (!hub->descriptor) {
579 message = "can't kmalloc hub descriptor";
584 /* Request the entire hub descriptor.
585 * hub->descriptor can handle USB_MAXCHILDREN ports,
586 * but the hub can/will return fewer bytes here.
588 ret = get_hub_descriptor(hdev, hub->descriptor,
589 sizeof(*hub->descriptor));
591 message = "can't read hub descriptor";
593 } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
594 message = "hub has too many ports!";
599 hdev->maxchild = hub->descriptor->bNbrPorts;
600 dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
601 (hdev->maxchild == 1) ? "" : "s");
603 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
605 if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
607 char portstr [USB_MAXCHILDREN + 1];
609 for (i = 0; i < hdev->maxchild; i++)
610 portstr[i] = hub->descriptor->DeviceRemovable
611 [((i + 1) / 8)] & (1 << ((i + 1) % 8))
613 portstr[hdev->maxchild] = 0;
614 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
616 dev_dbg(hub_dev, "standalone hub\n");
618 switch (wHubCharacteristics & HUB_CHAR_LPSM) {
620 dev_dbg(hub_dev, "ganged power switching\n");
623 dev_dbg(hub_dev, "individual port power switching\n");
627 dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
631 switch (wHubCharacteristics & HUB_CHAR_OCPM) {
633 dev_dbg(hub_dev, "global over-current protection\n");
636 dev_dbg(hub_dev, "individual port over-current protection\n");
640 dev_dbg(hub_dev, "no over-current protection\n");
644 spin_lock_init (&hub->tt.lock);
645 INIT_LIST_HEAD (&hub->tt.clear_list);
646 INIT_WORK (&hub->tt.kevent, hub_tt_kevent);
647 switch (hdev->descriptor.bDeviceProtocol) {
651 dev_dbg(hub_dev, "Single TT\n");
655 ret = usb_set_interface(hdev, 0, 1);
657 dev_dbg(hub_dev, "TT per port\n");
660 dev_err(hub_dev, "Using single TT (err %d)\n",
665 dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
666 hdev->descriptor.bDeviceProtocol);
670 /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
671 switch (wHubCharacteristics & HUB_CHAR_TTTT) {
672 case HUB_TTTT_8_BITS:
673 if (hdev->descriptor.bDeviceProtocol != 0) {
674 hub->tt.think_time = 666;
675 dev_dbg(hub_dev, "TT requires at most %d "
676 "FS bit times (%d ns)\n",
677 8, hub->tt.think_time);
680 case HUB_TTTT_16_BITS:
681 hub->tt.think_time = 666 * 2;
682 dev_dbg(hub_dev, "TT requires at most %d "
683 "FS bit times (%d ns)\n",
684 16, hub->tt.think_time);
686 case HUB_TTTT_24_BITS:
687 hub->tt.think_time = 666 * 3;
688 dev_dbg(hub_dev, "TT requires at most %d "
689 "FS bit times (%d ns)\n",
690 24, hub->tt.think_time);
692 case HUB_TTTT_32_BITS:
693 hub->tt.think_time = 666 * 4;
694 dev_dbg(hub_dev, "TT requires at most %d "
695 "FS bit times (%d ns)\n",
696 32, hub->tt.think_time);
700 /* probe() zeroes hub->indicator[] */
701 if (wHubCharacteristics & HUB_CHAR_PORTIND) {
702 hub->has_indicators = 1;
703 dev_dbg(hub_dev, "Port indicators are supported\n");
706 dev_dbg(hub_dev, "power on to power good time: %dms\n",
707 hub->descriptor->bPwrOn2PwrGood * 2);
709 /* power budgeting mostly matters with bus-powered hubs,
710 * and battery-powered root hubs (may provide just 8 mA).
712 ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
714 message = "can't get hub status";
717 le16_to_cpus(&hubstatus);
718 if (hdev == hdev->bus->root_hub) {
719 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
720 hub->mA_per_port = 500;
722 hub->mA_per_port = hdev->bus_mA;
723 hub->limited_power = 1;
725 } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
726 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
727 hub->descriptor->bHubContrCurrent);
728 hub->limited_power = 1;
729 if (hdev->maxchild > 0) {
730 int remaining = hdev->bus_mA -
731 hub->descriptor->bHubContrCurrent;
733 if (remaining < hdev->maxchild * 100)
735 "insufficient power available "
736 "to use all downstream ports\n");
737 hub->mA_per_port = 100; /* 7.2.1.1 */
739 } else { /* Self-powered external hub */
740 /* FIXME: What about battery-powered external hubs that
741 * provide less current per port? */
742 hub->mA_per_port = 500;
744 if (hub->mA_per_port < 500)
745 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
748 ret = hub_hub_status(hub, &hubstatus, &hubchange);
750 message = "can't get hub status";
754 /* local power status reports aren't always correct */
755 if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
756 dev_dbg(hub_dev, "local power source is %s\n",
757 (hubstatus & HUB_STATUS_LOCAL_POWER)
758 ? "lost (inactive)" : "good");
760 if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
761 dev_dbg(hub_dev, "%sover-current condition exists\n",
762 (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
764 /* set up the interrupt endpoint */
765 pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
766 maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
768 if (maxp > sizeof(*hub->buffer))
769 maxp = sizeof(*hub->buffer);
771 hub->urb = usb_alloc_urb(0, GFP_KERNEL);
773 message = "couldn't allocate interrupt urb";
778 usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
779 hub, endpoint->bInterval);
780 hub->urb->transfer_dma = hub->buffer_dma;
781 hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
783 /* maybe cycle the hub leds */
784 if (hub->has_indicators && blinkenlights)
785 hub->indicator [0] = INDICATOR_CYCLE;
792 dev_err (hub_dev, "config failed, %s (err %d)\n",
794 /* hub_disconnect() frees urb and descriptor */
798 static unsigned highspeed_hubs;
800 static void hub_disconnect(struct usb_interface *intf)
802 struct usb_hub *hub = usb_get_intfdata (intf);
803 struct usb_device *hdev;
805 /* Disconnect all children and quiesce the hub */
809 usb_set_intfdata (intf, NULL);
812 if (hdev->speed == USB_SPEED_HIGH)
815 usb_free_urb(hub->urb);
818 spin_lock_irq(&hub_event_lock);
819 list_del_init(&hub->event_list);
820 spin_unlock_irq(&hub_event_lock);
822 kfree(hub->descriptor);
823 hub->descriptor = NULL;
829 usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
837 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
839 struct usb_host_interface *desc;
840 struct usb_endpoint_descriptor *endpoint;
841 struct usb_device *hdev;
844 desc = intf->cur_altsetting;
845 hdev = interface_to_usbdev(intf);
847 #ifdef CONFIG_USB_OTG_BLACKLIST_HUB
849 dev_warn(&intf->dev, "ignoring external hub\n");
854 /* Some hubs have a subclass of 1, which AFAICT according to the */
855 /* specs is not defined, but it works */
856 if ((desc->desc.bInterfaceSubClass != 0) &&
857 (desc->desc.bInterfaceSubClass != 1)) {
859 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
863 /* Multiple endpoints? What kind of mutant ninja-hub is this? */
864 if (desc->desc.bNumEndpoints != 1)
865 goto descriptor_error;
867 endpoint = &desc->endpoint[0].desc;
869 /* If it's not an interrupt in endpoint, we'd better punt! */
870 if (!usb_endpoint_is_int_in(endpoint))
871 goto descriptor_error;
874 dev_info (&intf->dev, "USB hub found\n");
876 hub = kzalloc(sizeof(*hub), GFP_KERNEL);
878 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
882 INIT_LIST_HEAD(&hub->event_list);
883 hub->intfdev = &intf->dev;
885 INIT_DELAYED_WORK(&hub->leds, led_work);
887 usb_set_intfdata (intf, hub);
889 if (hdev->speed == USB_SPEED_HIGH)
892 if (hub_configure(hub, endpoint) >= 0)
895 hub_disconnect (intf);
900 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
902 struct usb_device *hdev = interface_to_usbdev (intf);
904 /* assert ifno == 0 (part of hub spec) */
906 case USBDEVFS_HUB_PORTINFO: {
907 struct usbdevfs_hub_portinfo *info = user_data;
910 spin_lock_irq(&device_state_lock);
911 if (hdev->devnum <= 0)
914 info->nports = hdev->maxchild;
915 for (i = 0; i < info->nports; i++) {
916 if (hdev->children[i] == NULL)
920 hdev->children[i]->devnum;
923 spin_unlock_irq(&device_state_lock);
925 return info->nports + 1;
934 /* grab device/port lock, returning index of that port (zero based).
935 * protects the upstream link used by this device from concurrent
936 * tree operations like suspend, resume, reset, and disconnect, which
937 * apply to everything downstream of a given port.
939 static int locktree(struct usb_device *udev)
942 struct usb_device *hdev;
947 /* root hub is always the first lock in the series */
950 usb_lock_device(udev);
954 /* on the path from root to us, lock everything from
955 * top down, dropping parent locks when not needed
961 /* everything is fail-fast once disconnect
964 if (udev->state == USB_STATE_NOTATTACHED) {
965 usb_unlock_device(hdev);
969 /* when everyone grabs locks top->bottom,
970 * non-overlapping work may be concurrent
972 usb_lock_device(udev);
973 usb_unlock_device(hdev);
974 return udev->portnum;
977 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
981 for (i = 0; i < udev->maxchild; ++i) {
982 if (udev->children[i])
983 recursively_mark_NOTATTACHED(udev->children[i]);
985 udev->state = USB_STATE_NOTATTACHED;
989 * usb_set_device_state - change a device's current state (usbcore, hcds)
990 * @udev: pointer to device whose state should be changed
991 * @new_state: new state value to be stored
993 * udev->state is _not_ fully protected by the device lock. Although
994 * most transitions are made only while holding the lock, the state can
995 * can change to USB_STATE_NOTATTACHED at almost any time. This
996 * is so that devices can be marked as disconnected as soon as possible,
997 * without having to wait for any semaphores to be released. As a result,
998 * all changes to any device's state must be protected by the
999 * device_state_lock spinlock.
1001 * Once a device has been added to the device tree, all changes to its state
1002 * should be made using this routine. The state should _not_ be set directly.
1004 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1005 * Otherwise udev->state is set to new_state, and if new_state is
1006 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1007 * to USB_STATE_NOTATTACHED.
1009 void usb_set_device_state(struct usb_device *udev,
1010 enum usb_device_state new_state)
1012 unsigned long flags;
1014 spin_lock_irqsave(&device_state_lock, flags);
1015 if (udev->state == USB_STATE_NOTATTACHED)
1017 else if (new_state != USB_STATE_NOTATTACHED) {
1019 /* root hub wakeup capabilities are managed out-of-band
1020 * and may involve silicon errata ... ignore them here.
1023 if (udev->state == USB_STATE_SUSPENDED
1024 || new_state == USB_STATE_SUSPENDED)
1025 ; /* No change to wakeup settings */
1026 else if (new_state == USB_STATE_CONFIGURED)
1027 device_init_wakeup(&udev->dev,
1028 (udev->actconfig->desc.bmAttributes
1029 & USB_CONFIG_ATT_WAKEUP));
1031 device_init_wakeup(&udev->dev, 0);
1033 udev->state = new_state;
1035 recursively_mark_NOTATTACHED(udev);
1036 spin_unlock_irqrestore(&device_state_lock, flags);
1043 * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
1044 * @rhdev: struct usb_device for the root hub
1046 * The USB host controller driver calls this function when its root hub
1047 * is resumed and Vbus power has been interrupted or the controller
1048 * has been reset. The routine marks all the children of the root hub
1049 * as NOTATTACHED and marks logical connect-change events on their ports.
1051 void usb_root_hub_lost_power(struct usb_device *rhdev)
1053 struct usb_hub *hub;
1055 unsigned long flags;
1057 dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
1059 /* Make sure no potential wakeup events get lost,
1060 * by forcing the root hub to be resumed.
1062 rhdev->dev.power.prev_state.event = PM_EVENT_ON;
1064 spin_lock_irqsave(&device_state_lock, flags);
1065 hub = hdev_to_hub(rhdev);
1066 for (port1 = 1; port1 <= rhdev->maxchild; ++port1) {
1067 if (rhdev->children[port1 - 1]) {
1068 recursively_mark_NOTATTACHED(
1069 rhdev->children[port1 - 1]);
1070 set_bit(port1, hub->change_bits);
1073 spin_unlock_irqrestore(&device_state_lock, flags);
1075 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
1077 #endif /* CONFIG_PM */
1079 static void choose_address(struct usb_device *udev)
1082 struct usb_bus *bus = udev->bus;
1084 /* If khubd ever becomes multithreaded, this will need a lock */
1086 /* Try to allocate the next devnum beginning at bus->devnum_next. */
1087 devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1090 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1092 bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1095 set_bit(devnum, bus->devmap.devicemap);
1096 udev->devnum = devnum;
1100 static void release_address(struct usb_device *udev)
1102 if (udev->devnum > 0) {
1103 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1109 * usb_disconnect - disconnect a device (usbcore-internal)
1110 * @pdev: pointer to device being disconnected
1111 * Context: !in_interrupt ()
1113 * Something got disconnected. Get rid of it and all of its children.
1115 * If *pdev is a normal device then the parent hub must already be locked.
1116 * If *pdev is a root hub then this routine will acquire the
1117 * usb_bus_list_lock on behalf of the caller.
1119 * Only hub drivers (including virtual root hub drivers for host
1120 * controllers) should ever call this.
1122 * This call is synchronous, and may not be used in an interrupt context.
1124 void usb_disconnect(struct usb_device **pdev)
1126 struct usb_device *udev = *pdev;
1130 pr_debug ("%s nodev\n", __FUNCTION__);
1134 /* mark the device as inactive, so any further urb submissions for
1135 * this device (and any of its children) will fail immediately.
1136 * this quiesces everyting except pending urbs.
1138 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1139 dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1141 usb_lock_device(udev);
1143 /* Free up all the children before we remove this device */
1144 for (i = 0; i < USB_MAXCHILDREN; i++) {
1145 if (udev->children[i])
1146 usb_disconnect(&udev->children[i]);
1149 /* deallocate hcd/hardware state ... nuking all pending urbs and
1150 * cleaning up all state associated with the current configuration
1151 * so that the hardware is now fully quiesced.
1153 dev_dbg (&udev->dev, "unregistering device\n");
1154 usb_disable_device(udev, 0);
1156 usb_unlock_device(udev);
1158 /* Unregister the device. The device driver is responsible
1159 * for removing the device files from usbfs and sysfs and for
1160 * de-configuring the device.
1162 device_del(&udev->dev);
1164 /* Free the device number and delete the parent's children[]
1165 * (or root_hub) pointer.
1167 release_address(udev);
1169 /* Avoid races with recursively_mark_NOTATTACHED() */
1170 spin_lock_irq(&device_state_lock);
1172 spin_unlock_irq(&device_state_lock);
1174 put_device(&udev->dev);
1178 static void show_string(struct usb_device *udev, char *id, char *string)
1182 dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1186 static inline void show_string(struct usb_device *udev, char *id, char *string)
1191 #ifdef CONFIG_USB_OTG
1192 #include "otg_whitelist.h"
1193 static int __usb_port_suspend(struct usb_device *, int port1);
1197 * usb_new_device - perform initial device setup (usbcore-internal)
1198 * @udev: newly addressed device (in ADDRESS state)
1200 * This is called with devices which have been enumerated, but not yet
1201 * configured. The device descriptor is available, but not descriptors
1202 * for any device configuration. The caller must have locked either
1203 * the parent hub (if udev is a normal device) or else the
1204 * usb_bus_list_lock (if udev is a root hub). The parent's pointer to
1205 * udev has already been installed, but udev is not yet visible through
1206 * sysfs or other filesystem code.
1208 * Returns 0 for success (device is configured and listed, with its
1209 * interfaces, in sysfs); else a negative errno value.
1211 * This call is synchronous, and may not be used in an interrupt context.
1213 * Only the hub driver or root-hub registrar should ever call this.
1215 int usb_new_device(struct usb_device *udev)
1219 err = usb_get_configuration(udev);
1221 dev_err(&udev->dev, "can't read configurations, error %d\n",
1226 /* read the standard strings and cache them if present */
1227 udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1228 udev->manufacturer = usb_cache_string(udev,
1229 udev->descriptor.iManufacturer);
1230 udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1232 /* Tell the world! */
1233 dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1234 "SerialNumber=%d\n",
1235 udev->descriptor.iManufacturer,
1236 udev->descriptor.iProduct,
1237 udev->descriptor.iSerialNumber);
1238 show_string(udev, "Product", udev->product);
1239 show_string(udev, "Manufacturer", udev->manufacturer);
1240 show_string(udev, "SerialNumber", udev->serial);
1242 #ifdef CONFIG_USB_OTG
1244 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1245 * to wake us after we've powered off VBUS; and HNP, switching roles
1246 * "host" to "peripheral". The OTG descriptor helps figure this out.
1248 if (!udev->bus->is_b_host
1250 && udev->parent == udev->bus->root_hub) {
1251 struct usb_otg_descriptor *desc = 0;
1252 struct usb_bus *bus = udev->bus;
1254 /* descriptor may appear anywhere in config */
1255 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1256 le16_to_cpu(udev->config[0].desc.wTotalLength),
1257 USB_DT_OTG, (void **) &desc) == 0) {
1258 if (desc->bmAttributes & USB_OTG_HNP) {
1259 unsigned port1 = udev->portnum;
1261 dev_info(&udev->dev,
1262 "Dual-Role OTG device on %sHNP port\n",
1263 (port1 == bus->otg_port)
1266 /* enable HNP before suspend, it's simpler */
1267 if (port1 == bus->otg_port)
1268 bus->b_hnp_enable = 1;
1269 err = usb_control_msg(udev,
1270 usb_sndctrlpipe(udev, 0),
1271 USB_REQ_SET_FEATURE, 0,
1273 ? USB_DEVICE_B_HNP_ENABLE
1274 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1275 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1277 /* OTG MESSAGE: report errors here,
1278 * customize to match your product.
1280 dev_info(&udev->dev,
1281 "can't set HNP mode; %d\n",
1283 bus->b_hnp_enable = 0;
1289 if (!is_targeted(udev)) {
1291 /* Maybe it can talk to us, though we can't talk to it.
1292 * (Includes HNP test device.)
1294 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1295 err = __usb_port_suspend(udev, udev->bus->otg_port);
1297 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1304 /* Register the device. The device driver is responsible
1305 * for adding the device files to usbfs and sysfs and for
1306 * configuring the device.
1308 err = device_add (&udev->dev);
1310 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1317 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1322 static int hub_port_status(struct usb_hub *hub, int port1,
1323 u16 *status, u16 *change)
1327 ret = get_port_status(hub->hdev, port1, &hub->status->port);
1329 dev_err (hub->intfdev,
1330 "%s failed (err = %d)\n", __FUNCTION__, ret);
1332 *status = le16_to_cpu(hub->status->port.wPortStatus);
1333 *change = le16_to_cpu(hub->status->port.wPortChange);
1340 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
1341 static unsigned hub_is_wusb(struct usb_hub *hub)
1343 struct usb_hcd *hcd;
1344 if (hub->hdev->parent != NULL) /* not a root hub? */
1346 hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
1347 return hcd->wireless;
1351 #define PORT_RESET_TRIES 5
1352 #define SET_ADDRESS_TRIES 2
1353 #define GET_DESCRIPTOR_TRIES 2
1354 #define SET_CONFIG_TRIES (2 * (use_both_schemes + 1))
1355 #define USE_NEW_SCHEME(i) ((i) / 2 == old_scheme_first)
1357 #define HUB_ROOT_RESET_TIME 50 /* times are in msec */
1358 #define HUB_SHORT_RESET_TIME 10
1359 #define HUB_LONG_RESET_TIME 200
1360 #define HUB_RESET_TIMEOUT 500
1362 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1363 struct usb_device *udev, unsigned int delay)
1365 int delay_time, ret;
1369 for (delay_time = 0;
1370 delay_time < HUB_RESET_TIMEOUT;
1371 delay_time += delay) {
1372 /* wait to give the device a chance to reset */
1375 /* read and decode port status */
1376 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1380 /* Device went away? */
1381 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1384 /* bomb out completely if something weird happened */
1385 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1388 /* if we`ve finished resetting, then break out of the loop */
1389 if (!(portstatus & USB_PORT_STAT_RESET) &&
1390 (portstatus & USB_PORT_STAT_ENABLE)) {
1391 if (hub_is_wusb(hub))
1392 udev->speed = USB_SPEED_VARIABLE;
1393 else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1394 udev->speed = USB_SPEED_HIGH;
1395 else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1396 udev->speed = USB_SPEED_LOW;
1398 udev->speed = USB_SPEED_FULL;
1402 /* switch to the long delay after two short delay failures */
1403 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1404 delay = HUB_LONG_RESET_TIME;
1406 dev_dbg (hub->intfdev,
1407 "port %d not reset yet, waiting %dms\n",
1414 static int hub_port_reset(struct usb_hub *hub, int port1,
1415 struct usb_device *udev, unsigned int delay)
1419 /* Reset the port */
1420 for (i = 0; i < PORT_RESET_TRIES; i++) {
1421 status = set_port_feature(hub->hdev,
1422 port1, USB_PORT_FEAT_RESET);
1424 dev_err(hub->intfdev,
1425 "cannot reset port %d (err = %d)\n",
1428 status = hub_port_wait_reset(hub, port1, udev, delay);
1429 if (status && status != -ENOTCONN)
1430 dev_dbg(hub->intfdev,
1431 "port_wait_reset: err = %d\n",
1435 /* return on disconnect or reset */
1438 /* TRSTRCY = 10 ms; plus some extra */
1443 clear_port_feature(hub->hdev,
1444 port1, USB_PORT_FEAT_C_RESET);
1445 /* FIXME need disconnect() for NOTATTACHED device */
1446 usb_set_device_state(udev, status
1447 ? USB_STATE_NOTATTACHED
1448 : USB_STATE_DEFAULT);
1452 dev_dbg (hub->intfdev,
1453 "port %d not enabled, trying reset again...\n",
1455 delay = HUB_LONG_RESET_TIME;
1458 dev_err (hub->intfdev,
1459 "Cannot enable port %i. Maybe the USB cable is bad?\n",
1466 * Disable a port and mark a logical connnect-change event, so that some
1467 * time later khubd will disconnect() any existing usb_device on the port
1468 * and will re-enumerate if there actually is a device attached.
1470 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1472 dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1473 hub_port_disable(hub, port1, 1);
1475 /* FIXME let caller ask to power down the port:
1476 * - some devices won't enumerate without a VBUS power cycle
1477 * - SRP saves power that way
1478 * - ... new call, TBD ...
1479 * That's easy if this hub can switch power per-port, and
1480 * khubd reactivates the port later (timer, SRP, etc).
1481 * Powerdown must be optional, because of reset/DFU.
1484 set_bit(port1, hub->change_bits);
1490 #ifdef CONFIG_USB_SUSPEND
1493 * Selective port suspend reduces power; most suspended devices draw
1494 * less than 500 uA. It's also used in OTG, along with remote wakeup.
1495 * All devices below the suspended port are also suspended.
1497 * Devices leave suspend state when the host wakes them up. Some devices
1498 * also support "remote wakeup", where the device can activate the USB
1499 * tree above them to deliver data, such as a keypress or packet. In
1500 * some cases, this wakes the USB host.
1502 static int hub_port_suspend(struct usb_hub *hub, int port1,
1503 struct usb_device *udev)
1507 // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1509 /* enable remote wakeup when appropriate; this lets the device
1510 * wake up the upstream hub (including maybe the root hub).
1512 * NOTE: OTG devices may issue remote wakeup (or SRP) even when
1513 * we don't explicitly enable it here.
1515 if (udev->do_remote_wakeup) {
1516 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1517 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1518 USB_DEVICE_REMOTE_WAKEUP, 0,
1520 USB_CTRL_SET_TIMEOUT);
1523 "won't remote wakeup, status %d\n",
1528 status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1530 dev_dbg(hub->intfdev,
1531 "can't suspend port %d, status %d\n",
1533 /* paranoia: "should not happen" */
1534 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1535 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1536 USB_DEVICE_REMOTE_WAKEUP, 0,
1538 USB_CTRL_SET_TIMEOUT);
1540 /* device has up to 10 msec to fully suspend */
1541 dev_dbg(&udev->dev, "usb %ssuspend\n",
1542 udev->auto_pm ? "auto-" : "");
1543 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1550 * Devices on USB hub ports have only one "suspend" state, corresponding
1551 * to ACPI D2, "may cause the device to lose some context".
1552 * State transitions include:
1554 * - suspend, resume ... when the VBUS power link stays live
1555 * - suspend, disconnect ... VBUS lost
1557 * Once VBUS drop breaks the circuit, the port it's using has to go through
1558 * normal re-enumeration procedures, starting with enabling VBUS power.
1559 * Other than re-initializing the hub (plug/unplug, except for root hubs),
1560 * Linux (2.6) currently has NO mechanisms to initiate that: no khubd
1561 * timer, no SRP, no requests through sysfs.
1563 * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1564 * the root hub for their bus goes into global suspend ... so we don't
1565 * (falsely) update the device power state to say it suspended.
1567 static int __usb_port_suspend (struct usb_device *udev, int port1)
1571 /* caller owns the udev device lock */
1575 /* we change the device's upstream USB link,
1576 * but root hubs have no upstream USB link.
1579 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1582 dev_dbg(&udev->dev, "usb %ssuspend\n",
1583 udev->auto_pm ? "auto-" : "");
1584 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1590 * usb_port_suspend - suspend a usb device's upstream port
1591 * @udev: device that's no longer in active use
1592 * Context: must be able to sleep; device not locked; pm locks held
1594 * Suspends a USB device that isn't in active use, conserving power.
1595 * Devices may wake out of a suspend, if anything important happens,
1596 * using the remote wakeup mechanism. They may also be taken out of
1597 * suspend by the host, using usb_port_resume(). It's also routine
1598 * to disconnect devices while they are suspended.
1600 * This only affects the USB hardware for a device; its interfaces
1601 * (and, for hubs, child devices) must already have been suspended.
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.
1607 * Returns 0 on success, else negative errno.
1609 int usb_port_suspend(struct usb_device *udev)
1611 return __usb_port_suspend(udev, udev->portnum);
1615 * If the USB "suspend" state is in use (rather than "global suspend"),
1616 * many devices will be individually taken out of suspend state using
1617 * special" resume" signaling. These routines kick in shortly after
1618 * hardware resume signaling is finished, either because of selective
1619 * resume (by host) or remote wakeup (by device) ... now see what changed
1620 * in the tree that's rooted at this device.
1622 static int finish_port_resume(struct usb_device *udev)
1627 /* caller owns the udev device lock */
1628 dev_dbg(&udev->dev, "finish resume\n");
1630 /* usb ch9 identifies four variants of SUSPENDED, based on what
1631 * state the device resumes to. Linux currently won't see the
1632 * first two on the host side; they'd be inside hub_port_init()
1633 * during many timeouts, but khubd can't suspend until later.
1635 usb_set_device_state(udev, udev->actconfig
1636 ? USB_STATE_CONFIGURED
1637 : USB_STATE_ADDRESS);
1639 /* 10.5.4.5 says be sure devices in the tree are still there.
1640 * For now let's assume the device didn't go crazy on resume,
1641 * and device drivers will know about any resume quirks.
1643 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1645 status = (status == 2 ? 0 : -ENODEV);
1649 "gone after usb resume? status %d\n",
1651 else if (udev->actconfig) {
1652 le16_to_cpus(&devstatus);
1653 if ((devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
1655 status = usb_control_msg(udev,
1656 usb_sndctrlpipe(udev, 0),
1657 USB_REQ_CLEAR_FEATURE,
1659 USB_DEVICE_REMOTE_WAKEUP, 0,
1661 USB_CTRL_SET_TIMEOUT);
1663 dev_dbg(&udev->dev, "disable remote "
1664 "wakeup, status %d\n", status);
1668 } else if (udev->devnum <= 0) {
1669 dev_dbg(&udev->dev, "bogus resume!\n");
1676 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1680 // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1682 set_bit(port1, hub->busy_bits);
1684 /* see 7.1.7.7; affects power usage, but not budgeting */
1685 status = clear_port_feature(hub->hdev,
1686 port1, USB_PORT_FEAT_SUSPEND);
1688 dev_dbg(hub->intfdev,
1689 "can't resume port %d, status %d\n",
1695 /* drive resume for at least 20 msec */
1697 dev_dbg(&udev->dev, "usb %sresume\n",
1698 udev->auto_pm ? "auto-" : "");
1701 #define LIVE_FLAGS ( USB_PORT_STAT_POWER \
1702 | USB_PORT_STAT_ENABLE \
1703 | USB_PORT_STAT_CONNECTION)
1705 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1706 * stop resume signaling. Then finish the resume
1709 devstatus = portchange = 0;
1710 status = hub_port_status(hub, port1,
1711 &devstatus, &portchange);
1713 || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
1714 || (devstatus & USB_PORT_STAT_SUSPEND) != 0
1716 dev_dbg(hub->intfdev,
1717 "port %d status %04x.%04x after resume, %d\n",
1718 port1, portchange, devstatus, status);
1722 if (portchange & USB_PORT_STAT_C_SUSPEND)
1723 clear_port_feature(hub->hdev, port1,
1724 USB_PORT_FEAT_C_SUSPEND);
1725 /* TRSMRCY = 10 msec */
1728 status = finish_port_resume(udev);
1732 hub_port_logical_disconnect(hub, port1);
1734 clear_bit(port1, hub->busy_bits);
1735 if (!hub->hdev->parent && !hub->busy_bits[0])
1736 usb_enable_root_hub_irq(hub->hdev->bus);
1742 * usb_port_resume - re-activate a suspended usb device's upstream port
1743 * @udev: device to re-activate
1744 * Context: must be able to sleep; device not locked; pm locks held
1746 * This will re-activate the suspended device, increasing power usage
1747 * while letting drivers communicate again with its endpoints.
1748 * USB resume explicitly guarantees that the power session between
1749 * the host and the device is the same as it was when the device
1752 * Returns 0 on success, else negative errno.
1754 int usb_port_resume(struct usb_device *udev)
1758 /* we change the device's upstream USB link,
1759 * but root hubs have no upstream USB link.
1762 // NOTE this fails if parent is also suspended...
1763 status = hub_port_resume(hdev_to_hub(udev->parent),
1764 udev->portnum, udev);
1766 dev_dbg(&udev->dev, "usb %sresume\n",
1767 udev->auto_pm ? "auto-" : "");
1768 status = finish_port_resume(udev);
1771 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
1775 static int remote_wakeup(struct usb_device *udev)
1779 /* All this just to avoid sending a port-resume message
1780 * to the parent hub! */
1782 usb_lock_device(udev);
1784 if (udev->state == USB_STATE_SUSPENDED) {
1785 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
1786 /* TRSMRCY = 10 msec */
1788 status = finish_port_resume(udev);
1790 udev->dev.power.power_state.event = PM_EVENT_ON;
1792 usb_pm_unlock(udev);
1795 usb_autoresume_device(udev, 0);
1796 usb_unlock_device(udev);
1800 #else /* CONFIG_USB_SUSPEND */
1802 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
1804 int usb_port_suspend(struct usb_device *udev)
1810 finish_port_resume(struct usb_device *udev)
1816 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1821 int usb_port_resume(struct usb_device *udev)
1826 static inline int remote_wakeup(struct usb_device *udev)
1833 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
1835 struct usb_hub *hub = usb_get_intfdata (intf);
1836 struct usb_device *hdev = hub->hdev;
1839 /* fail if children aren't already suspended */
1840 for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1841 struct usb_device *udev;
1843 udev = hdev->children [port1-1];
1844 if (udev && msg.event == PM_EVENT_SUSPEND &&
1845 #ifdef CONFIG_USB_SUSPEND
1846 udev->state != USB_STATE_SUSPENDED
1848 udev->dev.power.power_state.event
1853 dev_dbg(&intf->dev, "port %d nyet suspended\n",
1859 /* "global suspend" of the downstream HC-to-USB interface */
1860 if (!hdev->parent) {
1861 struct usb_bus *bus = hdev->bus;
1863 int status = hcd_bus_suspend (bus);
1866 dev_dbg(&hdev->dev, "'global' suspend %d\n",
1874 /* stop khubd and related activity */
1879 static int hub_resume(struct usb_interface *intf)
1881 struct usb_device *hdev = interface_to_usbdev(intf);
1882 struct usb_hub *hub = usb_get_intfdata (intf);
1885 /* "global resume" of the downstream HC-to-USB interface */
1886 if (!hdev->parent) {
1887 struct usb_bus *bus = hdev->bus;
1889 status = hcd_bus_resume (bus);
1891 dev_dbg(&intf->dev, "'global' resume %d\n",
1898 /* TRSMRCY = 10 msec */
1903 /* tell khubd to look for changes on this hub */
1908 #else /* CONFIG_PM */
1910 static inline int remote_wakeup(struct usb_device *udev)
1915 #define hub_suspend NULL
1916 #define hub_resume NULL
1919 void usb_resume_root_hub(struct usb_device *hdev)
1921 struct usb_hub *hub = hdev_to_hub(hdev);
1923 hub->resume_root_hub = 1;
1928 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
1930 * Between connect detection and reset signaling there must be a delay
1931 * of 100ms at least for debounce and power-settling. The corresponding
1932 * timer shall restart whenever the downstream port detects a disconnect.
1934 * Apparently there are some bluetooth and irda-dongles and a number of
1935 * low-speed devices for which this debounce period may last over a second.
1936 * Not covered by the spec - but easy to deal with.
1938 * This implementation uses a 1500ms total debounce timeout; if the
1939 * connection isn't stable by then it returns -ETIMEDOUT. It checks
1940 * every 25ms for transient disconnects. When the port status has been
1941 * unchanged for 100ms it returns the port status.
1944 #define HUB_DEBOUNCE_TIMEOUT 1500
1945 #define HUB_DEBOUNCE_STEP 25
1946 #define HUB_DEBOUNCE_STABLE 100
1948 static int hub_port_debounce(struct usb_hub *hub, int port1)
1951 int total_time, stable_time = 0;
1952 u16 portchange, portstatus;
1953 unsigned connection = 0xffff;
1955 for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
1956 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1960 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
1961 (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
1962 stable_time += HUB_DEBOUNCE_STEP;
1963 if (stable_time >= HUB_DEBOUNCE_STABLE)
1967 connection = portstatus & USB_PORT_STAT_CONNECTION;
1970 if (portchange & USB_PORT_STAT_C_CONNECTION) {
1971 clear_port_feature(hub->hdev, port1,
1972 USB_PORT_FEAT_C_CONNECTION);
1975 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
1977 msleep(HUB_DEBOUNCE_STEP);
1980 dev_dbg (hub->intfdev,
1981 "debounce: port %d: total %dms stable %dms status 0x%x\n",
1982 port1, total_time, stable_time, portstatus);
1984 if (stable_time < HUB_DEBOUNCE_STABLE)
1989 static void ep0_reinit(struct usb_device *udev)
1991 usb_disable_endpoint(udev, 0 + USB_DIR_IN);
1992 usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
1993 udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
1996 #define usb_sndaddr0pipe() (PIPE_CONTROL << 30)
1997 #define usb_rcvaddr0pipe() ((PIPE_CONTROL << 30) | USB_DIR_IN)
1999 static int hub_set_address(struct usb_device *udev)
2003 if (udev->devnum == 0)
2005 if (udev->state == USB_STATE_ADDRESS)
2007 if (udev->state != USB_STATE_DEFAULT)
2009 retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2010 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2011 NULL, 0, USB_CTRL_SET_TIMEOUT);
2013 usb_set_device_state(udev, USB_STATE_ADDRESS);
2019 /* Reset device, (re)assign address, get device descriptor.
2020 * Device connection must be stable, no more debouncing needed.
2021 * Returns device in USB_STATE_ADDRESS, except on error.
2023 * If this is called for an already-existing device (as part of
2024 * usb_reset_device), the caller must own the device lock. For a
2025 * newly detected device that is not accessible through any global
2026 * pointers, it's not necessary to lock the device.
2029 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2032 static DEFINE_MUTEX(usb_address0_mutex);
2034 struct usb_device *hdev = hub->hdev;
2036 unsigned delay = HUB_SHORT_RESET_TIME;
2037 enum usb_device_speed oldspeed = udev->speed;
2040 /* root hub ports have a slightly longer reset period
2041 * (from USB 2.0 spec, section 7.1.7.5)
2043 if (!hdev->parent) {
2044 delay = HUB_ROOT_RESET_TIME;
2045 if (port1 == hdev->bus->otg_port)
2046 hdev->bus->b_hnp_enable = 0;
2049 /* Some low speed devices have problems with the quick delay, so */
2050 /* be a bit pessimistic with those devices. RHbug #23670 */
2051 if (oldspeed == USB_SPEED_LOW)
2052 delay = HUB_LONG_RESET_TIME;
2054 mutex_lock(&usb_address0_mutex);
2056 /* Reset the device; full speed may morph to high speed */
2057 retval = hub_port_reset(hub, port1, udev, delay);
2058 if (retval < 0) /* error or disconnect */
2060 /* success, speed is known */
2063 if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2064 dev_dbg(&udev->dev, "device reset changed speed!\n");
2067 oldspeed = udev->speed;
2069 /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2070 * it's fixed size except for full speed devices.
2071 * For Wireless USB devices, ep0 max packet is always 512 (tho
2072 * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
2074 switch (udev->speed) {
2075 case USB_SPEED_VARIABLE: /* fixed at 512 */
2076 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(512);
2078 case USB_SPEED_HIGH: /* fixed at 64 */
2079 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2081 case USB_SPEED_FULL: /* 8, 16, 32, or 64 */
2082 /* to determine the ep0 maxpacket size, try to read
2083 * the device descriptor to get bMaxPacketSize0 and
2084 * then correct our initial guess.
2086 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2088 case USB_SPEED_LOW: /* fixed at 8 */
2089 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2096 switch (udev->speed) {
2097 case USB_SPEED_LOW: speed = "low"; break;
2098 case USB_SPEED_FULL: speed = "full"; break;
2099 case USB_SPEED_HIGH: speed = "high"; break;
2100 case USB_SPEED_VARIABLE:
2104 default: speed = "?"; break;
2106 dev_info (&udev->dev,
2107 "%s %s speed %sUSB device using %s and address %d\n",
2108 (udev->config) ? "reset" : "new", speed, type,
2109 udev->bus->controller->driver->name, udev->devnum);
2111 /* Set up TT records, if needed */
2113 udev->tt = hdev->tt;
2114 udev->ttport = hdev->ttport;
2115 } else if (udev->speed != USB_SPEED_HIGH
2116 && hdev->speed == USB_SPEED_HIGH) {
2117 udev->tt = &hub->tt;
2118 udev->ttport = port1;
2121 /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2122 * Because device hardware and firmware is sometimes buggy in
2123 * this area, and this is how Linux has done it for ages.
2124 * Change it cautiously.
2126 * NOTE: If USE_NEW_SCHEME() is true we will start by issuing
2127 * a 64-byte GET_DESCRIPTOR request. This is what Windows does,
2128 * so it may help with some non-standards-compliant devices.
2129 * Otherwise we start with SET_ADDRESS and then try to read the
2130 * first 8 bytes of the device descriptor to get the ep0 maxpacket
2133 for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2134 if (USE_NEW_SCHEME(retry_counter)) {
2135 struct usb_device_descriptor *buf;
2138 #define GET_DESCRIPTOR_BUFSIZE 64
2139 buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2145 /* Use a short timeout the first time through,
2146 * so that recalcitrant full-speed devices with
2147 * 8- or 16-byte ep0-maxpackets won't slow things
2148 * down tremendously by NAKing the unexpectedly
2149 * early status stage. Also, retry on all errors;
2150 * some devices are flakey.
2151 * 255 is for WUSB devices, we actually need to use 512.
2154 for (j = 0; j < 3; ++j) {
2155 buf->bMaxPacketSize0 = 0;
2156 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2157 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2158 USB_DT_DEVICE << 8, 0,
2159 buf, GET_DESCRIPTOR_BUFSIZE,
2160 (i ? USB_CTRL_GET_TIMEOUT : 1000));
2161 switch (buf->bMaxPacketSize0) {
2162 case 8: case 16: case 32: case 64: case 255:
2163 if (buf->bDescriptorType ==
2177 udev->descriptor.bMaxPacketSize0 =
2178 buf->bMaxPacketSize0;
2181 retval = hub_port_reset(hub, port1, udev, delay);
2182 if (retval < 0) /* error or disconnect */
2184 if (oldspeed != udev->speed) {
2186 "device reset changed speed!\n");
2191 dev_err(&udev->dev, "device descriptor "
2192 "read/%s, error %d\n",
2197 #undef GET_DESCRIPTOR_BUFSIZE
2200 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2201 retval = hub_set_address(udev);
2208 "device not accepting address %d, error %d\n",
2209 udev->devnum, retval);
2213 /* cope with hardware quirkiness:
2214 * - let SET_ADDRESS settle, some device hardware wants it
2215 * - read ep0 maxpacket even for high and low speed,
2218 if (USE_NEW_SCHEME(retry_counter))
2221 retval = usb_get_device_descriptor(udev, 8);
2223 dev_err(&udev->dev, "device descriptor "
2224 "read/%s, error %d\n",
2236 i = udev->descriptor.bMaxPacketSize0 == 0xff?
2237 512 : udev->descriptor.bMaxPacketSize0;
2238 if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2239 if (udev->speed != USB_SPEED_FULL ||
2240 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2241 dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2245 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2246 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2250 retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2251 if (retval < (signed)sizeof(udev->descriptor)) {
2252 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2263 hub_port_disable(hub, port1, 0);
2264 mutex_unlock(&usb_address0_mutex);
2269 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2271 struct usb_qualifier_descriptor *qual;
2274 qual = kmalloc (sizeof *qual, SLAB_KERNEL);
2278 status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2279 qual, sizeof *qual);
2280 if (status == sizeof *qual) {
2281 dev_info(&udev->dev, "not running at top speed; "
2282 "connect to a high speed hub\n");
2283 /* hub LEDs are probably harder to miss than syslog */
2284 if (hub->has_indicators) {
2285 hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2286 schedule_delayed_work (&hub->leds, 0);
2293 hub_power_remaining (struct usb_hub *hub)
2295 struct usb_device *hdev = hub->hdev;
2299 if (!hub->limited_power)
2302 remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
2303 for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
2304 struct usb_device *udev = hdev->children[port1 - 1];
2310 /* Unconfigured devices may not use more than 100mA,
2311 * or 8mA for OTG ports */
2312 if (udev->actconfig)
2313 delta = udev->actconfig->desc.bMaxPower * 2;
2314 else if (port1 != udev->bus->otg_port || hdev->parent)
2318 if (delta > hub->mA_per_port)
2319 dev_warn(&udev->dev, "%dmA is over %umA budget "
2321 delta, hub->mA_per_port, port1);
2324 if (remaining < 0) {
2325 dev_warn(hub->intfdev, "%dmA over power budget!\n",
2332 /* Handle physical or logical connection change events.
2333 * This routine is called when:
2334 * a port connection-change occurs;
2335 * a port enable-change occurs (often caused by EMI);
2336 * usb_reset_device() encounters changed descriptors (as from
2337 * a firmware download)
2338 * caller already locked the hub
2340 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2341 u16 portstatus, u16 portchange)
2343 struct usb_device *hdev = hub->hdev;
2344 struct device *hub_dev = hub->intfdev;
2345 u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2349 "port %d, status %04x, change %04x, %s\n",
2350 port1, portstatus, portchange, portspeed (portstatus));
2352 if (hub->has_indicators) {
2353 set_port_led(hub, port1, HUB_LED_AUTO);
2354 hub->indicator[port1-1] = INDICATOR_AUTO;
2357 /* Disconnect any existing devices under this port */
2358 if (hdev->children[port1-1])
2359 usb_disconnect(&hdev->children[port1-1]);
2360 clear_bit(port1, hub->change_bits);
2362 #ifdef CONFIG_USB_OTG
2363 /* during HNP, don't repeat the debounce */
2364 if (hdev->bus->is_b_host)
2365 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2368 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2369 status = hub_port_debounce(hub, port1);
2372 "connect-debounce failed, port %d disabled\n",
2376 portstatus = status;
2379 /* Return now if nothing is connected */
2380 if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2382 /* maybe switch power back on (e.g. root hub was reset) */
2383 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
2384 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2385 set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2387 if (portstatus & USB_PORT_STAT_ENABLE)
2392 #ifdef CONFIG_USB_SUSPEND
2393 /* If something is connected, but the port is suspended, wake it up. */
2394 if (portstatus & USB_PORT_STAT_SUSPEND) {
2395 status = hub_port_resume(hub, port1, NULL);
2398 "can't clear suspend on port %d; %d\n",
2405 for (i = 0; i < SET_CONFIG_TRIES; i++) {
2406 struct usb_device *udev;
2408 /* reallocate for each attempt, since references
2409 * to the previous one can escape in various ways
2411 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2414 "couldn't allocate port %d usb_device\n",
2419 usb_set_device_state(udev, USB_STATE_POWERED);
2420 udev->speed = USB_SPEED_UNKNOWN;
2421 udev->bus_mA = hub->mA_per_port;
2422 udev->level = hdev->level + 1;
2424 /* set the address */
2425 choose_address(udev);
2426 if (udev->devnum <= 0) {
2427 status = -ENOTCONN; /* Don't retry */
2431 /* reset and get descriptor */
2432 status = hub_port_init(hub, udev, port1, i);
2436 /* consecutive bus-powered hubs aren't reliable; they can
2437 * violate the voltage drop budget. if the new child has
2438 * a "powered" LED, users should notice we didn't enable it
2439 * (without reading syslog), even without per-port LEDs
2442 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2443 && udev->bus_mA <= 100) {
2446 status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2449 dev_dbg(&udev->dev, "get status %d ?\n", status);
2452 le16_to_cpus(&devstat);
2453 if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2455 "can't connect bus-powered hub "
2457 if (hub->has_indicators) {
2458 hub->indicator[port1-1] =
2459 INDICATOR_AMBER_BLINK;
2460 schedule_delayed_work (&hub->leds, 0);
2462 status = -ENOTCONN; /* Don't retry */
2467 /* check for devices running slower than they could */
2468 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2469 && udev->speed == USB_SPEED_FULL
2470 && highspeed_hubs != 0)
2471 check_highspeed (hub, udev, port1);
2473 /* Store the parent's children[] pointer. At this point
2474 * udev becomes globally accessible, although presumably
2475 * no one will look at it until hdev is unlocked.
2479 /* We mustn't add new devices if the parent hub has
2480 * been disconnected; we would race with the
2481 * recursively_mark_NOTATTACHED() routine.
2483 spin_lock_irq(&device_state_lock);
2484 if (hdev->state == USB_STATE_NOTATTACHED)
2487 hdev->children[port1-1] = udev;
2488 spin_unlock_irq(&device_state_lock);
2490 /* Run it through the hoops (find a driver, etc) */
2492 status = usb_new_device(udev);
2494 spin_lock_irq(&device_state_lock);
2495 hdev->children[port1-1] = NULL;
2496 spin_unlock_irq(&device_state_lock);
2503 status = hub_power_remaining(hub);
2505 dev_dbg(hub_dev, "%dmA power budget left\n", status);
2510 hub_port_disable(hub, port1, 1);
2513 release_address(udev);
2515 if (status == -ENOTCONN)
2520 hub_port_disable(hub, port1, 1);
2523 static void hub_events(void)
2525 struct list_head *tmp;
2526 struct usb_device *hdev;
2527 struct usb_interface *intf;
2528 struct usb_hub *hub;
2529 struct device *hub_dev;
2538 * We restart the list every time to avoid a deadlock with
2539 * deleting hubs downstream from this one. This should be
2540 * safe since we delete the hub from the event list.
2541 * Not the most efficient, but avoids deadlocks.
2545 /* Grab the first entry at the beginning of the list */
2546 spin_lock_irq(&hub_event_lock);
2547 if (list_empty(&hub_event_list)) {
2548 spin_unlock_irq(&hub_event_lock);
2552 tmp = hub_event_list.next;
2555 hub = list_entry(tmp, struct usb_hub, event_list);
2557 intf = to_usb_interface(hub->intfdev);
2558 hub_dev = &intf->dev;
2560 i = hub->resume_root_hub;
2562 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x%s\n",
2563 hdev->state, hub->descriptor
2564 ? hub->descriptor->bNbrPorts
2566 /* NOTE: expects max 15 ports... */
2567 (u16) hub->change_bits[0],
2568 (u16) hub->event_bits[0],
2569 i ? ", resume root" : "");
2572 spin_unlock_irq(&hub_event_lock);
2574 /* Lock the device, then check to see if we were
2575 * disconnected while waiting for the lock to succeed. */
2576 if (locktree(hdev) < 0) {
2580 if (hub != usb_get_intfdata(intf))
2583 /* If the hub has died, clean up after it */
2584 if (hdev->state == USB_STATE_NOTATTACHED) {
2585 hub->error = -ENODEV;
2586 hub_pre_reset(intf);
2590 /* Is this is a root hub wanting to reactivate the downstream
2591 * ports? If so, be sure the interface resumes even if its
2592 * stub "device" node was never suspended.
2595 usb_autoresume_device(hdev, 0);
2597 /* If this is an inactive or suspended hub, do nothing */
2602 dev_dbg (hub_dev, "resetting for error %d\n",
2605 ret = usb_reset_composite_device(hdev, intf);
2608 "error resetting hub: %d\n", ret);
2616 /* deal with port status changes */
2617 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2618 if (test_bit(i, hub->busy_bits))
2620 connect_change = test_bit(i, hub->change_bits);
2621 if (!test_and_clear_bit(i, hub->event_bits) &&
2622 !connect_change && !hub->activating)
2625 ret = hub_port_status(hub, i,
2626 &portstatus, &portchange);
2630 if (hub->activating && !hdev->children[i-1] &&
2632 USB_PORT_STAT_CONNECTION))
2635 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2636 clear_port_feature(hdev, i,
2637 USB_PORT_FEAT_C_CONNECTION);
2641 if (portchange & USB_PORT_STAT_C_ENABLE) {
2642 if (!connect_change)
2644 "port %d enable change, "
2647 clear_port_feature(hdev, i,
2648 USB_PORT_FEAT_C_ENABLE);
2651 * EM interference sometimes causes badly
2652 * shielded USB devices to be shutdown by
2653 * the hub, this hack enables them again.
2654 * Works at least with mouse driver.
2656 if (!(portstatus & USB_PORT_STAT_ENABLE)
2658 && hdev->children[i-1]) {
2661 "disabled by hub (EMI?), "
2668 if (portchange & USB_PORT_STAT_C_SUSPEND) {
2669 clear_port_feature(hdev, i,
2670 USB_PORT_FEAT_C_SUSPEND);
2671 if (hdev->children[i-1]) {
2672 ret = remote_wakeup(hdev->
2678 hub_port_disable(hub, i, 1);
2681 "resume on port %d, status %d\n",
2685 if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2687 "over-current change on port %d\n",
2689 clear_port_feature(hdev, i,
2690 USB_PORT_FEAT_C_OVER_CURRENT);
2694 if (portchange & USB_PORT_STAT_C_RESET) {
2696 "reset change on port %d\n",
2698 clear_port_feature(hdev, i,
2699 USB_PORT_FEAT_C_RESET);
2703 hub_port_connect_change(hub, i,
2704 portstatus, portchange);
2707 /* deal with hub status changes */
2708 if (test_and_clear_bit(0, hub->event_bits) == 0)
2710 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2711 dev_err (hub_dev, "get_hub_status failed\n");
2713 if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2714 dev_dbg (hub_dev, "power change\n");
2715 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2716 if (hubstatus & HUB_STATUS_LOCAL_POWER)
2717 /* FIXME: Is this always true? */
2718 hub->limited_power = 0;
2720 hub->limited_power = 1;
2722 if (hubchange & HUB_CHANGE_OVERCURRENT) {
2723 dev_dbg (hub_dev, "overcurrent change\n");
2724 msleep(500); /* Cool down */
2725 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2730 hub->activating = 0;
2732 /* If this is a root hub, tell the HCD it's okay to
2733 * re-enable port-change interrupts now. */
2734 if (!hdev->parent && !hub->busy_bits[0])
2735 usb_enable_root_hub_irq(hdev->bus);
2738 usb_unlock_device(hdev);
2741 } /* end while (1) */
2744 static int hub_thread(void *__unused)
2748 wait_event_interruptible(khubd_wait,
2749 !list_empty(&hub_event_list) ||
2750 kthread_should_stop());
2752 } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2754 pr_debug("%s: khubd exiting\n", usbcore_name);
2758 static struct usb_device_id hub_id_table [] = {
2759 { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2760 .bDeviceClass = USB_CLASS_HUB},
2761 { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2762 .bInterfaceClass = USB_CLASS_HUB},
2763 { } /* Terminating entry */
2766 MODULE_DEVICE_TABLE (usb, hub_id_table);
2768 static struct usb_driver hub_driver = {
2771 .disconnect = hub_disconnect,
2772 .suspend = hub_suspend,
2773 .resume = hub_resume,
2774 .pre_reset = hub_pre_reset,
2775 .post_reset = hub_post_reset,
2777 .id_table = hub_id_table,
2780 int usb_hub_init(void)
2782 if (usb_register(&hub_driver) < 0) {
2783 printk(KERN_ERR "%s: can't register hub driver\n",
2788 khubd_task = kthread_run(hub_thread, NULL, "khubd");
2789 if (!IS_ERR(khubd_task))
2792 /* Fall through if kernel_thread failed */
2793 usb_deregister(&hub_driver);
2794 printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2799 void usb_hub_cleanup(void)
2801 kthread_stop(khubd_task);
2804 * Hub resources are freed for us by usb_deregister. It calls
2805 * usb_driver_purge on every device which in turn calls that
2806 * devices disconnect function if it is using this driver.
2807 * The hub_disconnect function takes care of releasing the
2808 * individual hub resources. -greg
2810 usb_deregister(&hub_driver);
2811 } /* usb_hub_cleanup() */
2813 static int config_descriptors_changed(struct usb_device *udev)
2817 struct usb_config_descriptor *buf;
2819 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2820 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2821 len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2823 buf = kmalloc (len, SLAB_KERNEL);
2825 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2826 /* assume the worst */
2829 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2831 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2833 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2835 if (length < old_length) {
2836 dev_dbg(&udev->dev, "config index %d, error %d\n",
2840 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2842 dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2843 index, buf->bConfigurationValue);
2848 return index != udev->descriptor.bNumConfigurations;
2852 * usb_reset_device - perform a USB port reset to reinitialize a device
2853 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2855 * WARNING - don't use this routine to reset a composite device
2856 * (one with multiple interfaces owned by separate drivers)!
2857 * Use usb_reset_composite_device() instead.
2859 * Do a port reset, reassign the device's address, and establish its
2860 * former operating configuration. If the reset fails, or the device's
2861 * descriptors change from their values before the reset, or the original
2862 * configuration and altsettings cannot be restored, a flag will be set
2863 * telling khubd to pretend the device has been disconnected and then
2864 * re-connected. All drivers will be unbound, and the device will be
2865 * re-enumerated and probed all over again.
2867 * Returns 0 if the reset succeeded, -ENODEV if the device has been
2868 * flagged for logical disconnection, or some other negative error code
2869 * if the reset wasn't even attempted.
2871 * The caller must own the device lock. For example, it's safe to use
2872 * this from a driver probe() routine after downloading new firmware.
2873 * For calls that might not occur during probe(), drivers should lock
2874 * the device using usb_lock_device_for_reset().
2876 int usb_reset_device(struct usb_device *udev)
2878 struct usb_device *parent_hdev = udev->parent;
2879 struct usb_hub *parent_hub;
2880 struct usb_device_descriptor descriptor = udev->descriptor;
2882 int port1 = udev->portnum;
2884 if (udev->state == USB_STATE_NOTATTACHED ||
2885 udev->state == USB_STATE_SUSPENDED) {
2886 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2892 /* this requires hcd-specific logic; see OHCI hc_restart() */
2893 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2896 parent_hub = hdev_to_hub(parent_hdev);
2898 set_bit(port1, parent_hub->busy_bits);
2899 for (i = 0; i < SET_CONFIG_TRIES; ++i) {
2901 /* ep0 maxpacket size may change; let the HCD know about it.
2902 * Other endpoints will be handled by re-enumeration. */
2904 ret = hub_port_init(parent_hub, udev, port1, i);
2908 clear_bit(port1, parent_hub->busy_bits);
2909 if (!parent_hdev->parent && !parent_hub->busy_bits[0])
2910 usb_enable_root_hub_irq(parent_hdev->bus);
2915 /* Device might have changed firmware (DFU or similar) */
2916 if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
2917 || config_descriptors_changed (udev)) {
2918 dev_info(&udev->dev, "device firmware changed\n");
2919 udev->descriptor = descriptor; /* for disconnect() calls */
2923 if (!udev->actconfig)
2926 ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2927 USB_REQ_SET_CONFIGURATION, 0,
2928 udev->actconfig->desc.bConfigurationValue, 0,
2929 NULL, 0, USB_CTRL_SET_TIMEOUT);
2932 "can't restore configuration #%d (error=%d)\n",
2933 udev->actconfig->desc.bConfigurationValue, ret);
2936 usb_set_device_state(udev, USB_STATE_CONFIGURED);
2938 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
2939 struct usb_interface *intf = udev->actconfig->interface[i];
2940 struct usb_interface_descriptor *desc;
2942 /* set_interface resets host side toggle even
2943 * for altsetting zero. the interface may have no driver.
2945 desc = &intf->cur_altsetting->desc;
2946 ret = usb_set_interface(udev, desc->bInterfaceNumber,
2947 desc->bAlternateSetting);
2949 dev_err(&udev->dev, "failed to restore interface %d "
2950 "altsetting %d (error=%d)\n",
2951 desc->bInterfaceNumber,
2952 desc->bAlternateSetting,
2962 hub_port_logical_disconnect(parent_hub, port1);
2965 EXPORT_SYMBOL(usb_reset_device);
2968 * usb_reset_composite_device - warn interface drivers and perform a USB port reset
2969 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2970 * @iface: interface bound to the driver making the request (optional)
2972 * Warns all drivers bound to registered interfaces (using their pre_reset
2973 * method), performs the port reset, and then lets the drivers know that
2974 * the reset is over (using their post_reset method).
2976 * Return value is the same as for usb_reset_device().
2978 * The caller must own the device lock. For example, it's safe to use
2979 * this from a driver probe() routine after downloading new firmware.
2980 * For calls that might not occur during probe(), drivers should lock
2981 * the device using usb_lock_device_for_reset().
2983 * The interface locks are acquired during the pre_reset stage and released
2984 * during the post_reset stage. However if iface is not NULL and is
2985 * currently being probed, we assume that the caller already owns its
2988 int usb_reset_composite_device(struct usb_device *udev,
2989 struct usb_interface *iface)
2992 struct usb_host_config *config = udev->actconfig;
2994 if (udev->state == USB_STATE_NOTATTACHED ||
2995 udev->state == USB_STATE_SUSPENDED) {
2996 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3001 /* Prevent autosuspend during the reset */
3002 usb_autoresume_device(udev, 1);
3004 if (iface && iface->condition != USB_INTERFACE_BINDING)
3009 struct usb_interface *cintf;
3010 struct usb_driver *drv;
3012 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
3013 cintf = config->interface[i];
3015 down(&cintf->dev.sem);
3016 if (device_is_registered(&cintf->dev) &&
3017 cintf->dev.driver) {
3018 drv = to_usb_driver(cintf->dev.driver);
3020 (drv->pre_reset)(cintf);
3025 ret = usb_reset_device(udev);
3029 struct usb_interface *cintf;
3030 struct usb_driver *drv;
3032 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
3033 cintf = config->interface[i];
3034 if (device_is_registered(&cintf->dev) &&
3035 cintf->dev.driver) {
3036 drv = to_usb_driver(cintf->dev.driver);
3037 if (drv->post_reset)
3038 (drv->post_reset)(cintf);
3041 up(&cintf->dev.sem);
3045 usb_autosuspend_device(udev, 1);
3048 EXPORT_SYMBOL(usb_reset_composite_device);