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/config.h>
12 #include <linux/kernel.h>
13 #include <linux/errno.h>
14 #include <linux/module.h>
15 #include <linux/moduleparam.h>
16 #include <linux/completion.h>
17 #include <linux/sched.h>
18 #include <linux/list.h>
19 #include <linux/slab.h>
20 #include <linux/smp_lock.h>
21 #include <linux/ioctl.h>
22 #include <linux/usb.h>
23 #include <linux/usbdevice_fs.h>
24 #include <linux/kthread.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 (void *__hub)
172 struct usb_hub *hub = __hub;
173 struct usb_device *hdev = hub->hdev;
175 unsigned changed = 0;
178 if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
181 for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
182 unsigned selector, mode;
184 /* 30%-50% duty cycle */
186 switch (hub->indicator[i]) {
188 case INDICATOR_CYCLE:
190 selector = HUB_LED_AUTO;
191 mode = INDICATOR_AUTO;
193 /* blinking green = sw attention */
194 case INDICATOR_GREEN_BLINK:
195 selector = HUB_LED_GREEN;
196 mode = INDICATOR_GREEN_BLINK_OFF;
198 case INDICATOR_GREEN_BLINK_OFF:
199 selector = HUB_LED_OFF;
200 mode = INDICATOR_GREEN_BLINK;
202 /* blinking amber = hw attention */
203 case INDICATOR_AMBER_BLINK:
204 selector = HUB_LED_AMBER;
205 mode = INDICATOR_AMBER_BLINK_OFF;
207 case INDICATOR_AMBER_BLINK_OFF:
208 selector = HUB_LED_OFF;
209 mode = INDICATOR_AMBER_BLINK;
211 /* blink green/amber = reserved */
212 case INDICATOR_ALT_BLINK:
213 selector = HUB_LED_GREEN;
214 mode = INDICATOR_ALT_BLINK_OFF;
216 case INDICATOR_ALT_BLINK_OFF:
217 selector = HUB_LED_AMBER;
218 mode = INDICATOR_ALT_BLINK;
223 if (selector != HUB_LED_AUTO)
225 set_port_led(hub, i + 1, selector);
226 hub->indicator[i] = mode;
228 if (!changed && blinkenlights) {
230 cursor %= hub->descriptor->bNbrPorts;
231 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
232 hub->indicator[cursor] = INDICATOR_CYCLE;
236 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
239 /* use a short timeout for hub/port status fetches */
240 #define USB_STS_TIMEOUT 1000
241 #define USB_STS_RETRIES 5
244 * USB 2.0 spec Section 11.24.2.6
246 static int get_hub_status(struct usb_device *hdev,
247 struct usb_hub_status *data)
249 int i, status = -ETIMEDOUT;
251 for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
252 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
253 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
254 data, sizeof(*data), USB_STS_TIMEOUT);
260 * USB 2.0 spec Section 11.24.2.7
262 static int get_port_status(struct usb_device *hdev, int port1,
263 struct usb_port_status *data)
265 int i, status = -ETIMEDOUT;
267 for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
268 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
269 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
270 data, sizeof(*data), USB_STS_TIMEOUT);
275 static void kick_khubd(struct usb_hub *hub)
279 spin_lock_irqsave(&hub_event_lock, flags);
280 if (list_empty(&hub->event_list)) {
281 list_add_tail(&hub->event_list, &hub_event_list);
282 wake_up(&khubd_wait);
284 spin_unlock_irqrestore(&hub_event_lock, flags);
287 void usb_kick_khubd(struct usb_device *hdev)
289 kick_khubd(hdev_to_hub(hdev));
293 /* completion function, fires on port status changes and various faults */
294 static void hub_irq(struct urb *urb, struct pt_regs *regs)
296 struct usb_hub *hub = (struct usb_hub *)urb->context;
301 switch (urb->status) {
302 case -ENOENT: /* synchronous unlink */
303 case -ECONNRESET: /* async unlink */
304 case -ESHUTDOWN: /* hardware going away */
307 default: /* presumably an error */
308 /* Cause a hub reset after 10 consecutive errors */
309 dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
310 if ((++hub->nerrors < 10) || hub->error)
312 hub->error = urb->status;
315 /* let khubd handle things */
316 case 0: /* we got data: port status changed */
318 for (i = 0; i < urb->actual_length; ++i)
319 bits |= ((unsigned long) ((*hub->buffer)[i]))
321 hub->event_bits[0] = bits;
327 /* Something happened, let khubd figure it out */
334 if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
335 && status != -ENODEV && status != -EPERM)
336 dev_err (hub->intfdev, "resubmit --> %d\n", status);
339 /* USB 2.0 spec Section 11.24.2.3 */
341 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
343 return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
344 HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
349 * enumeration blocks khubd for a long time. we use keventd instead, since
350 * long blocking there is the exception, not the rule. accordingly, HCDs
351 * talking to TTs must queue control transfers (not just bulk and iso), so
352 * both can talk to the same hub concurrently.
354 static void hub_tt_kevent (void *arg)
356 struct usb_hub *hub = arg;
359 spin_lock_irqsave (&hub->tt.lock, flags);
360 while (!list_empty (&hub->tt.clear_list)) {
361 struct list_head *temp;
362 struct usb_tt_clear *clear;
363 struct usb_device *hdev = hub->hdev;
366 temp = hub->tt.clear_list.next;
367 clear = list_entry (temp, struct usb_tt_clear, clear_list);
368 list_del (&clear->clear_list);
370 /* drop lock so HCD can concurrently report other TT errors */
371 spin_unlock_irqrestore (&hub->tt.lock, flags);
372 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
373 spin_lock_irqsave (&hub->tt.lock, flags);
377 "clear tt %d (%04x) error %d\n",
378 clear->tt, clear->devinfo, status);
381 spin_unlock_irqrestore (&hub->tt.lock, flags);
385 * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
386 * @udev: the device whose split transaction failed
387 * @pipe: identifies the endpoint of the failed transaction
389 * High speed HCDs use this to tell the hub driver that some split control or
390 * bulk transaction failed in a way that requires clearing internal state of
391 * a transaction translator. This is normally detected (and reported) from
394 * It may not be possible for that hub to handle additional full (or low)
395 * speed transactions until that state is fully cleared out.
397 void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
399 struct usb_tt *tt = udev->tt;
401 struct usb_tt_clear *clear;
403 /* we've got to cope with an arbitrary number of pending TT clears,
404 * since each TT has "at least two" buffers that can need it (and
405 * there can be many TTs per hub). even if they're uncommon.
407 if ((clear = kmalloc (sizeof *clear, SLAB_ATOMIC)) == NULL) {
408 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
409 /* FIXME recover somehow ... RESET_TT? */
413 /* info that CLEAR_TT_BUFFER needs */
414 clear->tt = tt->multi ? udev->ttport : 1;
415 clear->devinfo = usb_pipeendpoint (pipe);
416 clear->devinfo |= udev->devnum << 4;
417 clear->devinfo |= usb_pipecontrol (pipe)
418 ? (USB_ENDPOINT_XFER_CONTROL << 11)
419 : (USB_ENDPOINT_XFER_BULK << 11);
420 if (usb_pipein (pipe))
421 clear->devinfo |= 1 << 15;
423 /* tell keventd to clear state for this TT */
424 spin_lock_irqsave (&tt->lock, flags);
425 list_add_tail (&clear->clear_list, &tt->clear_list);
426 schedule_work (&tt->kevent);
427 spin_unlock_irqrestore (&tt->lock, flags);
430 static void hub_power_on(struct usb_hub *hub)
433 unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
434 u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
436 /* if hub supports power switching, enable power on each port */
437 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2) {
438 dev_dbg(hub->intfdev, "enabling power on all ports\n");
439 for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
440 set_port_feature(hub->hdev, port1,
441 USB_PORT_FEAT_POWER);
444 /* Wait at least 100 msec for power to become stable */
445 msleep(max(pgood_delay, (unsigned) 100));
448 static inline void __hub_quiesce(struct usb_hub *hub)
450 /* (nonblocking) khubd and related activity won't re-trigger */
453 hub->resume_root_hub = 0;
456 static void hub_quiesce(struct usb_hub *hub)
458 /* (blocking) stop khubd and related activity */
460 usb_kill_urb(hub->urb);
461 if (hub->has_indicators)
462 cancel_delayed_work(&hub->leds);
463 if (hub->has_indicators || hub->tt.hub)
464 flush_scheduled_work();
467 static void hub_activate(struct usb_hub *hub)
473 hub->resume_root_hub = 0;
474 status = usb_submit_urb(hub->urb, GFP_NOIO);
476 dev_err(hub->intfdev, "activate --> %d\n", status);
477 if (hub->has_indicators && blinkenlights)
478 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
480 /* scan all ports ASAP */
484 static int hub_hub_status(struct usb_hub *hub,
485 u16 *status, u16 *change)
489 ret = get_hub_status(hub->hdev, &hub->status->hub);
491 dev_err (hub->intfdev,
492 "%s failed (err = %d)\n", __FUNCTION__, ret);
494 *status = le16_to_cpu(hub->status->hub.wHubStatus);
495 *change = le16_to_cpu(hub->status->hub.wHubChange);
501 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
503 struct usb_device *hdev = hub->hdev;
506 if (hdev->children[port1-1] && set_state) {
507 usb_set_device_state(hdev->children[port1-1],
508 USB_STATE_NOTATTACHED);
510 ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
512 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
519 /* caller has locked the hub device */
520 static void hub_pre_reset(struct usb_hub *hub, int disable_ports)
522 struct usb_device *hdev = hub->hdev;
525 for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
526 if (hdev->children[port1 - 1]) {
527 usb_disconnect(&hdev->children[port1 - 1]);
529 hub_port_disable(hub, port1, 0);
535 /* caller has locked the hub device */
536 static void hub_post_reset(struct usb_hub *hub)
543 static int hub_configure(struct usb_hub *hub,
544 struct usb_endpoint_descriptor *endpoint)
546 struct usb_device *hdev = hub->hdev;
547 struct device *hub_dev = hub->intfdev;
548 u16 hubstatus, hubchange;
549 u16 wHubCharacteristics;
554 hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
557 message = "can't allocate hub irq buffer";
562 hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
564 message = "can't kmalloc hub status buffer";
569 hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
570 if (!hub->descriptor) {
571 message = "can't kmalloc hub descriptor";
576 /* Request the entire hub descriptor.
577 * hub->descriptor can handle USB_MAXCHILDREN ports,
578 * but the hub can/will return fewer bytes here.
580 ret = get_hub_descriptor(hdev, hub->descriptor,
581 sizeof(*hub->descriptor));
583 message = "can't read hub descriptor";
585 } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
586 message = "hub has too many ports!";
591 hdev->maxchild = hub->descriptor->bNbrPorts;
592 dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
593 (hdev->maxchild == 1) ? "" : "s");
595 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
597 if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
599 char portstr [USB_MAXCHILDREN + 1];
601 for (i = 0; i < hdev->maxchild; i++)
602 portstr[i] = hub->descriptor->DeviceRemovable
603 [((i + 1) / 8)] & (1 << ((i + 1) % 8))
605 portstr[hdev->maxchild] = 0;
606 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
608 dev_dbg(hub_dev, "standalone hub\n");
610 switch (wHubCharacteristics & HUB_CHAR_LPSM) {
612 dev_dbg(hub_dev, "ganged power switching\n");
615 dev_dbg(hub_dev, "individual port power switching\n");
619 dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
623 switch (wHubCharacteristics & HUB_CHAR_OCPM) {
625 dev_dbg(hub_dev, "global over-current protection\n");
628 dev_dbg(hub_dev, "individual port over-current protection\n");
632 dev_dbg(hub_dev, "no over-current protection\n");
636 spin_lock_init (&hub->tt.lock);
637 INIT_LIST_HEAD (&hub->tt.clear_list);
638 INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub);
639 switch (hdev->descriptor.bDeviceProtocol) {
643 dev_dbg(hub_dev, "Single TT\n");
647 ret = usb_set_interface(hdev, 0, 1);
649 dev_dbg(hub_dev, "TT per port\n");
652 dev_err(hub_dev, "Using single TT (err %d)\n",
657 dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
658 hdev->descriptor.bDeviceProtocol);
662 /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
663 switch (wHubCharacteristics & HUB_CHAR_TTTT) {
664 case HUB_TTTT_8_BITS:
665 if (hdev->descriptor.bDeviceProtocol != 0) {
666 hub->tt.think_time = 666;
667 dev_dbg(hub_dev, "TT requires at most %d "
668 "FS bit times (%d ns)\n",
669 8, hub->tt.think_time);
672 case HUB_TTTT_16_BITS:
673 hub->tt.think_time = 666 * 2;
674 dev_dbg(hub_dev, "TT requires at most %d "
675 "FS bit times (%d ns)\n",
676 16, hub->tt.think_time);
678 case HUB_TTTT_24_BITS:
679 hub->tt.think_time = 666 * 3;
680 dev_dbg(hub_dev, "TT requires at most %d "
681 "FS bit times (%d ns)\n",
682 24, hub->tt.think_time);
684 case HUB_TTTT_32_BITS:
685 hub->tt.think_time = 666 * 4;
686 dev_dbg(hub_dev, "TT requires at most %d "
687 "FS bit times (%d ns)\n",
688 32, hub->tt.think_time);
692 /* probe() zeroes hub->indicator[] */
693 if (wHubCharacteristics & HUB_CHAR_PORTIND) {
694 hub->has_indicators = 1;
695 dev_dbg(hub_dev, "Port indicators are supported\n");
698 dev_dbg(hub_dev, "power on to power good time: %dms\n",
699 hub->descriptor->bPwrOn2PwrGood * 2);
701 /* power budgeting mostly matters with bus-powered hubs,
702 * and battery-powered root hubs (may provide just 8 mA).
704 ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
706 message = "can't get hub status";
709 le16_to_cpus(&hubstatus);
710 if (hdev == hdev->bus->root_hub) {
711 struct usb_hcd *hcd =
712 container_of(hdev->bus, struct usb_hcd, self);
714 hub->power_budget = min(500u, hcd->power_budget) / 2;
715 } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
716 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
717 hub->descriptor->bHubContrCurrent);
718 hub->power_budget = (501 - hub->descriptor->bHubContrCurrent)
721 if (hub->power_budget)
722 dev_dbg(hub_dev, "%dmA bus power budget for children\n",
723 hub->power_budget * 2);
726 ret = hub_hub_status(hub, &hubstatus, &hubchange);
728 message = "can't get hub status";
732 /* local power status reports aren't always correct */
733 if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
734 dev_dbg(hub_dev, "local power source is %s\n",
735 (hubstatus & HUB_STATUS_LOCAL_POWER)
736 ? "lost (inactive)" : "good");
738 if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
739 dev_dbg(hub_dev, "%sover-current condition exists\n",
740 (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
742 /* set up the interrupt endpoint */
743 pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
744 maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
746 if (maxp > sizeof(*hub->buffer))
747 maxp = sizeof(*hub->buffer);
749 hub->urb = usb_alloc_urb(0, GFP_KERNEL);
751 message = "couldn't allocate interrupt urb";
756 usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
757 hub, endpoint->bInterval);
758 hub->urb->transfer_dma = hub->buffer_dma;
759 hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
761 /* maybe cycle the hub leds */
762 if (hub->has_indicators && blinkenlights)
763 hub->indicator [0] = INDICATOR_CYCLE;
770 dev_err (hub_dev, "config failed, %s (err %d)\n",
772 /* hub_disconnect() frees urb and descriptor */
776 static unsigned highspeed_hubs;
778 static void hub_disconnect(struct usb_interface *intf)
780 struct usb_hub *hub = usb_get_intfdata (intf);
781 struct usb_device *hdev;
783 usb_set_intfdata (intf, NULL);
786 if (hdev->speed == USB_SPEED_HIGH)
789 /* Disconnect all children and quiesce the hub */
790 hub_pre_reset(hub, 1);
792 usb_free_urb(hub->urb);
795 spin_lock_irq(&hub_event_lock);
796 list_del_init(&hub->event_list);
797 spin_unlock_irq(&hub_event_lock);
799 kfree(hub->descriptor);
800 hub->descriptor = NULL;
806 usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
814 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
816 struct usb_host_interface *desc;
817 struct usb_endpoint_descriptor *endpoint;
818 struct usb_device *hdev;
821 desc = intf->cur_altsetting;
822 hdev = interface_to_usbdev(intf);
824 /* Some hubs have a subclass of 1, which AFAICT according to the */
825 /* specs is not defined, but it works */
826 if ((desc->desc.bInterfaceSubClass != 0) &&
827 (desc->desc.bInterfaceSubClass != 1)) {
829 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
833 /* Multiple endpoints? What kind of mutant ninja-hub is this? */
834 if (desc->desc.bNumEndpoints != 1)
835 goto descriptor_error;
837 endpoint = &desc->endpoint[0].desc;
839 /* Output endpoint? Curiouser and curiouser.. */
840 if (!(endpoint->bEndpointAddress & USB_DIR_IN))
841 goto descriptor_error;
843 /* If it's not an interrupt endpoint, we'd better punt! */
844 if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
845 != USB_ENDPOINT_XFER_INT)
846 goto descriptor_error;
849 dev_info (&intf->dev, "USB hub found\n");
851 hub = kzalloc(sizeof(*hub), GFP_KERNEL);
853 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
857 INIT_LIST_HEAD(&hub->event_list);
858 hub->intfdev = &intf->dev;
860 INIT_WORK(&hub->leds, led_work, hub);
862 usb_set_intfdata (intf, hub);
864 if (hdev->speed == USB_SPEED_HIGH)
867 if (hub_configure(hub, endpoint) >= 0)
870 hub_disconnect (intf);
875 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
877 struct usb_device *hdev = interface_to_usbdev (intf);
879 /* assert ifno == 0 (part of hub spec) */
881 case USBDEVFS_HUB_PORTINFO: {
882 struct usbdevfs_hub_portinfo *info = user_data;
885 spin_lock_irq(&device_state_lock);
886 if (hdev->devnum <= 0)
889 info->nports = hdev->maxchild;
890 for (i = 0; i < info->nports; i++) {
891 if (hdev->children[i] == NULL)
895 hdev->children[i]->devnum;
898 spin_unlock_irq(&device_state_lock);
900 return info->nports + 1;
909 /* grab device/port lock, returning index of that port (zero based).
910 * protects the upstream link used by this device from concurrent
911 * tree operations like suspend, resume, reset, and disconnect, which
912 * apply to everything downstream of a given port.
914 static int locktree(struct usb_device *udev)
917 struct usb_device *hdev;
922 /* root hub is always the first lock in the series */
925 usb_lock_device(udev);
929 /* on the path from root to us, lock everything from
930 * top down, dropping parent locks when not needed
935 for (t = 0; t < hdev->maxchild; t++) {
936 if (hdev->children[t] == udev) {
937 /* everything is fail-fast once disconnect
940 if (udev->state == USB_STATE_NOTATTACHED)
943 /* when everyone grabs locks top->bottom,
944 * non-overlapping work may be concurrent
946 usb_lock_device(udev);
947 usb_unlock_device(hdev);
951 usb_unlock_device(hdev);
955 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
959 for (i = 0; i < udev->maxchild; ++i) {
960 if (udev->children[i])
961 recursively_mark_NOTATTACHED(udev->children[i]);
963 udev->state = USB_STATE_NOTATTACHED;
967 * usb_set_device_state - change a device's current state (usbcore, hcds)
968 * @udev: pointer to device whose state should be changed
969 * @new_state: new state value to be stored
971 * udev->state is _not_ fully protected by the device lock. Although
972 * most transitions are made only while holding the lock, the state can
973 * can change to USB_STATE_NOTATTACHED at almost any time. This
974 * is so that devices can be marked as disconnected as soon as possible,
975 * without having to wait for any semaphores to be released. As a result,
976 * all changes to any device's state must be protected by the
977 * device_state_lock spinlock.
979 * Once a device has been added to the device tree, all changes to its state
980 * should be made using this routine. The state should _not_ be set directly.
982 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
983 * Otherwise udev->state is set to new_state, and if new_state is
984 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
985 * to USB_STATE_NOTATTACHED.
987 void usb_set_device_state(struct usb_device *udev,
988 enum usb_device_state new_state)
992 spin_lock_irqsave(&device_state_lock, flags);
993 if (udev->state == USB_STATE_NOTATTACHED)
995 else if (new_state != USB_STATE_NOTATTACHED) {
996 udev->state = new_state;
997 if (new_state == USB_STATE_CONFIGURED)
998 device_init_wakeup(&udev->dev,
999 (udev->actconfig->desc.bmAttributes
1000 & USB_CONFIG_ATT_WAKEUP));
1001 else if (new_state != USB_STATE_SUSPENDED)
1002 device_init_wakeup(&udev->dev, 0);
1004 recursively_mark_NOTATTACHED(udev);
1005 spin_unlock_irqrestore(&device_state_lock, flags);
1007 EXPORT_SYMBOL(usb_set_device_state);
1013 * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
1014 * @rhdev: struct usb_device for the root hub
1016 * The USB host controller driver calls this function when its root hub
1017 * is resumed and Vbus power has been interrupted or the controller
1018 * has been reset. The routine marks all the children of the root hub
1019 * as NOTATTACHED and marks logical connect-change events on their ports.
1021 void usb_root_hub_lost_power(struct usb_device *rhdev)
1023 struct usb_hub *hub;
1025 unsigned long flags;
1027 dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
1028 spin_lock_irqsave(&device_state_lock, flags);
1029 hub = hdev_to_hub(rhdev);
1030 for (port1 = 1; port1 <= rhdev->maxchild; ++port1) {
1031 if (rhdev->children[port1 - 1]) {
1032 recursively_mark_NOTATTACHED(
1033 rhdev->children[port1 - 1]);
1034 set_bit(port1, hub->change_bits);
1037 spin_unlock_irqrestore(&device_state_lock, flags);
1039 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
1043 static void choose_address(struct usb_device *udev)
1046 struct usb_bus *bus = udev->bus;
1048 /* If khubd ever becomes multithreaded, this will need a lock */
1050 /* Try to allocate the next devnum beginning at bus->devnum_next. */
1051 devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1054 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1056 bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1059 set_bit(devnum, bus->devmap.devicemap);
1060 udev->devnum = devnum;
1064 static void release_address(struct usb_device *udev)
1066 if (udev->devnum > 0) {
1067 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1073 * usb_disconnect - disconnect a device (usbcore-internal)
1074 * @pdev: pointer to device being disconnected
1075 * Context: !in_interrupt ()
1077 * Something got disconnected. Get rid of it and all of its children.
1079 * If *pdev is a normal device then the parent hub must already be locked.
1080 * If *pdev is a root hub then this routine will acquire the
1081 * usb_bus_list_lock on behalf of the caller.
1083 * Only hub drivers (including virtual root hub drivers for host
1084 * controllers) should ever call this.
1086 * This call is synchronous, and may not be used in an interrupt context.
1088 void usb_disconnect(struct usb_device **pdev)
1090 struct usb_device *udev = *pdev;
1094 pr_debug ("%s nodev\n", __FUNCTION__);
1098 /* mark the device as inactive, so any further urb submissions for
1099 * this device (and any of its children) will fail immediately.
1100 * this quiesces everyting except pending urbs.
1102 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1103 dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1105 usb_lock_device(udev);
1107 /* Free up all the children before we remove this device */
1108 for (i = 0; i < USB_MAXCHILDREN; i++) {
1109 if (udev->children[i])
1110 usb_disconnect(&udev->children[i]);
1113 /* deallocate hcd/hardware state ... nuking all pending urbs and
1114 * cleaning up all state associated with the current configuration
1115 * so that the hardware is now fully quiesced.
1117 usb_disable_device(udev, 0);
1119 usb_notify_remove_device(udev);
1121 /* Free the device number, remove the /proc/bus/usb entry and
1122 * the sysfs attributes, and delete the parent's children[]
1123 * (or root_hub) pointer.
1125 dev_dbg (&udev->dev, "unregistering device\n");
1126 release_address(udev);
1127 usb_remove_sysfs_dev_files(udev);
1129 /* Avoid races with recursively_mark_NOTATTACHED() */
1130 spin_lock_irq(&device_state_lock);
1132 spin_unlock_irq(&device_state_lock);
1134 usb_unlock_device(udev);
1136 device_unregister(&udev->dev);
1139 static int choose_configuration(struct usb_device *udev)
1143 /* NOTE: this should interact with hub power budgeting */
1145 c = udev->config[0].desc.bConfigurationValue;
1146 if (udev->descriptor.bNumConfigurations != 1) {
1147 for (i = 0; i < udev->descriptor.bNumConfigurations; i++) {
1148 struct usb_interface_descriptor *desc;
1150 /* heuristic: Linux is more likely to have class
1151 * drivers, so avoid vendor-specific interfaces.
1153 desc = &udev->config[i].intf_cache[0]
1155 if (desc->bInterfaceClass == USB_CLASS_VENDOR_SPEC)
1157 /* COMM/2/all is CDC ACM, except 0xff is MSFT RNDIS.
1158 * MSFT needs this to be the first config; never use
1159 * it as the default unless Linux has host-side RNDIS.
1160 * A second config would ideally be CDC-Ethernet, but
1161 * may instead be the "vendor specific" CDC subset
1162 * long used by ARM Linux for sa1100 or pxa255.
1164 if (desc->bInterfaceClass == USB_CLASS_COMM
1165 && desc->bInterfaceSubClass == 2
1166 && desc->bInterfaceProtocol == 0xff) {
1167 c = udev->config[1].desc.bConfigurationValue;
1170 c = udev->config[i].desc.bConfigurationValue;
1173 dev_info(&udev->dev,
1174 "configuration #%d chosen from %d choices\n",
1175 c, udev->descriptor.bNumConfigurations);
1181 static void show_string(struct usb_device *udev, char *id, char *string)
1185 dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1189 static inline void show_string(struct usb_device *udev, char *id, char *string)
1194 #ifdef CONFIG_USB_OTG
1195 #include "otg_whitelist.h"
1199 * usb_new_device - perform initial device setup (usbcore-internal)
1200 * @udev: newly addressed device (in ADDRESS state)
1202 * This is called with devices which have been enumerated, but not yet
1203 * configured. The device descriptor is available, but not descriptors
1204 * for any device configuration. The caller must have locked either
1205 * the parent hub (if udev is a normal device) or else the
1206 * usb_bus_list_lock (if udev is a root hub). The parent's pointer to
1207 * udev has already been installed, but udev is not yet visible through
1208 * sysfs or other filesystem code.
1210 * Returns 0 for success (device is configured and listed, with its
1211 * interfaces, in sysfs); else a negative errno value.
1213 * This call is synchronous, and may not be used in an interrupt context.
1215 * Only the hub driver or root-hub registrar should ever call this.
1217 int usb_new_device(struct usb_device *udev)
1222 err = usb_get_configuration(udev);
1224 dev_err(&udev->dev, "can't read configurations, error %d\n",
1229 /* read the standard strings and cache them if present */
1230 udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1231 udev->manufacturer = usb_cache_string(udev,
1232 udev->descriptor.iManufacturer);
1233 udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1235 /* Tell the world! */
1236 dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1237 "SerialNumber=%d\n",
1238 udev->descriptor.iManufacturer,
1239 udev->descriptor.iProduct,
1240 udev->descriptor.iSerialNumber);
1241 show_string(udev, "Product", udev->product);
1242 show_string(udev, "Manufacturer", udev->manufacturer);
1243 show_string(udev, "SerialNumber", udev->serial);
1245 #ifdef CONFIG_USB_OTG
1247 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1248 * to wake us after we've powered off VBUS; and HNP, switching roles
1249 * "host" to "peripheral". The OTG descriptor helps figure this out.
1251 if (!udev->bus->is_b_host
1253 && udev->parent == udev->bus->root_hub) {
1254 struct usb_otg_descriptor *desc = 0;
1255 struct usb_bus *bus = udev->bus;
1257 /* descriptor may appear anywhere in config */
1258 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1259 le16_to_cpu(udev->config[0].desc.wTotalLength),
1260 USB_DT_OTG, (void **) &desc) == 0) {
1261 if (desc->bmAttributes & USB_OTG_HNP) {
1263 struct usb_device *root = udev->parent;
1265 for (port1 = 1; port1 <= root->maxchild;
1267 if (root->children[port1-1] == udev)
1271 dev_info(&udev->dev,
1272 "Dual-Role OTG device on %sHNP port\n",
1273 (port1 == bus->otg_port)
1276 /* enable HNP before suspend, it's simpler */
1277 if (port1 == bus->otg_port)
1278 bus->b_hnp_enable = 1;
1279 err = usb_control_msg(udev,
1280 usb_sndctrlpipe(udev, 0),
1281 USB_REQ_SET_FEATURE, 0,
1283 ? USB_DEVICE_B_HNP_ENABLE
1284 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1285 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1287 /* OTG MESSAGE: report errors here,
1288 * customize to match your product.
1290 dev_info(&udev->dev,
1291 "can't set HNP mode; %d\n",
1293 bus->b_hnp_enable = 0;
1299 if (!is_targeted(udev)) {
1301 /* Maybe it can talk to us, though we can't talk to it.
1302 * (Includes HNP test device.)
1304 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1305 static int __usb_suspend_device(struct usb_device *,
1307 err = __usb_suspend_device(udev, udev->bus->otg_port);
1309 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1316 /* put device-specific files into sysfs */
1317 err = device_add (&udev->dev);
1319 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1322 usb_create_sysfs_dev_files (udev);
1324 usb_lock_device(udev);
1326 /* choose and set the configuration. that registers the interfaces
1327 * with the driver core, and lets usb device drivers bind to them.
1329 c = choose_configuration(udev);
1331 dev_warn(&udev->dev,
1332 "can't choose an initial configuration\n");
1334 err = usb_set_configuration(udev, c);
1336 dev_err(&udev->dev, "can't set config #%d, error %d\n",
1338 usb_remove_sysfs_dev_files(udev);
1339 device_del(&udev->dev);
1344 /* USB device state == configured ... usable */
1345 usb_notify_add_device(udev);
1347 usb_unlock_device(udev);
1352 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1357 static int hub_port_status(struct usb_hub *hub, int port1,
1358 u16 *status, u16 *change)
1362 ret = get_port_status(hub->hdev, port1, &hub->status->port);
1364 dev_err (hub->intfdev,
1365 "%s failed (err = %d)\n", __FUNCTION__, ret);
1367 *status = le16_to_cpu(hub->status->port.wPortStatus);
1368 *change = le16_to_cpu(hub->status->port.wPortChange);
1374 #define PORT_RESET_TRIES 5
1375 #define SET_ADDRESS_TRIES 2
1376 #define GET_DESCRIPTOR_TRIES 2
1377 #define SET_CONFIG_TRIES (2 * (use_both_schemes + 1))
1378 #define USE_NEW_SCHEME(i) ((i) / 2 == old_scheme_first)
1380 #define HUB_ROOT_RESET_TIME 50 /* times are in msec */
1381 #define HUB_SHORT_RESET_TIME 10
1382 #define HUB_LONG_RESET_TIME 200
1383 #define HUB_RESET_TIMEOUT 500
1385 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1386 struct usb_device *udev, unsigned int delay)
1388 int delay_time, ret;
1392 for (delay_time = 0;
1393 delay_time < HUB_RESET_TIMEOUT;
1394 delay_time += delay) {
1395 /* wait to give the device a chance to reset */
1398 /* read and decode port status */
1399 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1403 /* Device went away? */
1404 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1407 /* bomb out completely if something weird happened */
1408 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1411 /* if we`ve finished resetting, then break out of the loop */
1412 if (!(portstatus & USB_PORT_STAT_RESET) &&
1413 (portstatus & USB_PORT_STAT_ENABLE)) {
1414 if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1415 udev->speed = USB_SPEED_HIGH;
1416 else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1417 udev->speed = USB_SPEED_LOW;
1419 udev->speed = USB_SPEED_FULL;
1423 /* switch to the long delay after two short delay failures */
1424 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1425 delay = HUB_LONG_RESET_TIME;
1427 dev_dbg (hub->intfdev,
1428 "port %d not reset yet, waiting %dms\n",
1435 static int hub_port_reset(struct usb_hub *hub, int port1,
1436 struct usb_device *udev, unsigned int delay)
1440 /* Reset the port */
1441 for (i = 0; i < PORT_RESET_TRIES; i++) {
1442 status = set_port_feature(hub->hdev,
1443 port1, USB_PORT_FEAT_RESET);
1445 dev_err(hub->intfdev,
1446 "cannot reset port %d (err = %d)\n",
1449 status = hub_port_wait_reset(hub, port1, udev, delay);
1450 if (status && status != -ENOTCONN)
1451 dev_dbg(hub->intfdev,
1452 "port_wait_reset: err = %d\n",
1456 /* return on disconnect or reset */
1459 /* TRSTRCY = 10 ms; plus some extra */
1464 clear_port_feature(hub->hdev,
1465 port1, USB_PORT_FEAT_C_RESET);
1466 /* FIXME need disconnect() for NOTATTACHED device */
1467 usb_set_device_state(udev, status
1468 ? USB_STATE_NOTATTACHED
1469 : USB_STATE_DEFAULT);
1473 dev_dbg (hub->intfdev,
1474 "port %d not enabled, trying reset again...\n",
1476 delay = HUB_LONG_RESET_TIME;
1479 dev_err (hub->intfdev,
1480 "Cannot enable port %i. Maybe the USB cable is bad?\n",
1487 * Disable a port and mark a logical connnect-change event, so that some
1488 * time later khubd will disconnect() any existing usb_device on the port
1489 * and will re-enumerate if there actually is a device attached.
1491 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1493 dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1494 hub_port_disable(hub, port1, 1);
1496 /* FIXME let caller ask to power down the port:
1497 * - some devices won't enumerate without a VBUS power cycle
1498 * - SRP saves power that way
1499 * - ... new call, TBD ...
1500 * That's easy if this hub can switch power per-port, and
1501 * khubd reactivates the port later (timer, SRP, etc).
1502 * Powerdown must be optional, because of reset/DFU.
1505 set_bit(port1, hub->change_bits);
1510 #ifdef CONFIG_USB_SUSPEND
1513 * Selective port suspend reduces power; most suspended devices draw
1514 * less than 500 uA. It's also used in OTG, along with remote wakeup.
1515 * All devices below the suspended port are also suspended.
1517 * Devices leave suspend state when the host wakes them up. Some devices
1518 * also support "remote wakeup", where the device can activate the USB
1519 * tree above them to deliver data, such as a keypress or packet. In
1520 * some cases, this wakes the USB host.
1522 static int hub_port_suspend(struct usb_hub *hub, int port1,
1523 struct usb_device *udev)
1527 // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1529 /* enable remote wakeup when appropriate; this lets the device
1530 * wake up the upstream hub (including maybe the root hub).
1532 * NOTE: OTG devices may issue remote wakeup (or SRP) even when
1533 * we don't explicitly enable it here.
1535 if (device_may_wakeup(&udev->dev)) {
1536 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1537 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1538 USB_DEVICE_REMOTE_WAKEUP, 0,
1540 USB_CTRL_SET_TIMEOUT);
1543 "won't remote wakeup, status %d\n",
1548 status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1550 dev_dbg(hub->intfdev,
1551 "can't suspend port %d, status %d\n",
1553 /* paranoia: "should not happen" */
1554 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1555 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1556 USB_DEVICE_REMOTE_WAKEUP, 0,
1558 USB_CTRL_SET_TIMEOUT);
1560 /* device has up to 10 msec to fully suspend */
1561 dev_dbg(&udev->dev, "usb suspend\n");
1562 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1569 * Devices on USB hub ports have only one "suspend" state, corresponding
1570 * to ACPI D2, "may cause the device to lose some context".
1571 * State transitions include:
1573 * - suspend, resume ... when the VBUS power link stays live
1574 * - suspend, disconnect ... VBUS lost
1576 * Once VBUS drop breaks the circuit, the port it's using has to go through
1577 * normal re-enumeration procedures, starting with enabling VBUS power.
1578 * Other than re-initializing the hub (plug/unplug, except for root hubs),
1579 * Linux (2.6) currently has NO mechanisms to initiate that: no khubd
1580 * timer, no SRP, no requests through sysfs.
1582 * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1583 * the root hub for their bus goes into global suspend ... so we don't
1584 * (falsely) update the device power state to say it suspended.
1586 static int __usb_suspend_device (struct usb_device *udev, int port1)
1590 /* caller owns the udev device lock */
1594 if (udev->state == USB_STATE_SUSPENDED
1595 || udev->state == USB_STATE_NOTATTACHED) {
1599 /* all interfaces must already be suspended */
1600 if (udev->actconfig) {
1603 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1604 struct usb_interface *intf;
1606 intf = udev->actconfig->interface[i];
1607 if (is_active(intf)) {
1608 dev_dbg(&intf->dev, "nyet suspended\n");
1614 /* we only change a device's upstream USB link.
1615 * root hubs have no upstream USB link.
1618 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1622 udev->dev.power.power_state = PMSG_SUSPEND;
1629 * usb_suspend_device - suspend a usb device
1630 * @udev: device that's no longer in active use
1631 * Context: must be able to sleep; device not locked; pm locks held
1633 * Suspends a USB device that isn't in active use, conserving power.
1634 * Devices may wake out of a suspend, if anything important happens,
1635 * using the remote wakeup mechanism. They may also be taken out of
1636 * suspend by the host, using usb_resume_device(). It's also routine
1637 * to disconnect devices while they are suspended.
1639 * This only affects the USB hardware for a device; its interfaces
1640 * (and, for hubs, child devices) must already have been suspended.
1642 * Suspending OTG devices may trigger HNP, if that's been enabled
1643 * between a pair of dual-role devices. That will change roles, such
1644 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1646 * Returns 0 on success, else negative errno.
1648 int usb_suspend_device(struct usb_device *udev)
1650 #ifdef CONFIG_USB_SUSPEND
1653 port1 = locktree(udev);
1657 status = __usb_suspend_device(udev, port1);
1658 usb_unlock_device(udev);
1661 /* NOTE: udev->state unchanged, it's not lying ... */
1662 udev->dev.power.power_state = PMSG_SUSPEND;
1668 * If the USB "suspend" state is in use (rather than "global suspend"),
1669 * many devices will be individually taken out of suspend state using
1670 * special" resume" signaling. These routines kick in shortly after
1671 * hardware resume signaling is finished, either because of selective
1672 * resume (by host) or remote wakeup (by device) ... now see what changed
1673 * in the tree that's rooted at this device.
1675 static int finish_device_resume(struct usb_device *udev)
1680 /* caller owns the udev device lock */
1681 dev_dbg(&udev->dev, "finish resume\n");
1683 /* usb ch9 identifies four variants of SUSPENDED, based on what
1684 * state the device resumes to. Linux currently won't see the
1685 * first two on the host side; they'd be inside hub_port_init()
1686 * during many timeouts, but khubd can't suspend until later.
1688 usb_set_device_state(udev, udev->actconfig
1689 ? USB_STATE_CONFIGURED
1690 : USB_STATE_ADDRESS);
1692 /* 10.5.4.5 says be sure devices in the tree are still there.
1693 * For now let's assume the device didn't go crazy on resume,
1694 * and device drivers will know about any resume quirks.
1696 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1699 "gone after usb resume? status %d\n",
1701 else if (udev->actconfig) {
1703 int (*resume)(struct device *);
1705 le16_to_cpus(&devstatus);
1706 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)
1708 status = usb_control_msg(udev,
1709 usb_sndctrlpipe(udev, 0),
1710 USB_REQ_CLEAR_FEATURE,
1712 USB_DEVICE_REMOTE_WAKEUP, 0,
1714 USB_CTRL_SET_TIMEOUT);
1716 dev_dbg(&udev->dev, "disable remote "
1717 "wakeup, status %d\n", status);
1722 /* resume interface drivers; if this is a hub, it
1723 * may have a child resume event to deal with soon
1725 resume = udev->dev.bus->resume;
1726 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++)
1727 (void) resume(&udev->actconfig->interface[i]->dev);
1730 } else if (udev->devnum <= 0) {
1731 dev_dbg(&udev->dev, "bogus resume!\n");
1737 #ifdef CONFIG_USB_SUSPEND
1740 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1744 // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1746 /* see 7.1.7.7; affects power usage, but not budgeting */
1747 status = clear_port_feature(hub->hdev,
1748 port1, USB_PORT_FEAT_SUSPEND);
1750 dev_dbg(hub->intfdev,
1751 "can't resume port %d, status %d\n",
1757 /* drive resume for at least 20 msec */
1759 dev_dbg(&udev->dev, "RESUME\n");
1762 #define LIVE_FLAGS ( USB_PORT_STAT_POWER \
1763 | USB_PORT_STAT_ENABLE \
1764 | USB_PORT_STAT_CONNECTION)
1766 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1767 * stop resume signaling. Then finish the resume
1770 devstatus = portchange = 0;
1771 status = hub_port_status(hub, port1,
1772 &devstatus, &portchange);
1774 || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
1775 || (devstatus & USB_PORT_STAT_SUSPEND) != 0
1777 dev_dbg(hub->intfdev,
1778 "port %d status %04x.%04x after resume, %d\n",
1779 port1, portchange, devstatus, status);
1781 /* TRSMRCY = 10 msec */
1784 status = finish_device_resume(udev);
1788 hub_port_logical_disconnect(hub, port1);
1796 * usb_resume_device - re-activate a suspended usb device
1797 * @udev: device to re-activate
1798 * Context: must be able to sleep; device not locked; pm locks held
1800 * This will re-activate the suspended device, increasing power usage
1801 * while letting drivers communicate again with its endpoints.
1802 * USB resume explicitly guarantees that the power session between
1803 * the host and the device is the same as it was when the device
1806 * Returns 0 on success, else negative errno.
1808 int usb_resume_device(struct usb_device *udev)
1812 port1 = locktree(udev);
1816 #ifdef CONFIG_USB_SUSPEND
1817 /* selective resume of one downstream hub-to-device port */
1819 if (udev->state == USB_STATE_SUSPENDED) {
1820 // NOTE swsusp may bork us, device state being wrong...
1821 // NOTE this fails if parent is also suspended...
1822 status = hub_port_resume(hdev_to_hub(udev->parent),
1828 status = finish_device_resume(udev);
1830 dev_dbg(&udev->dev, "can't resume, status %d\n",
1833 usb_unlock_device(udev);
1835 /* rebind drivers that had no suspend() */
1837 bus_rescan_devices(&usb_bus_type);
1841 static int remote_wakeup(struct usb_device *udev)
1845 #ifdef CONFIG_USB_SUSPEND
1847 /* don't repeat RESUME sequence if this device
1848 * was already woken up by some other task
1850 usb_lock_device(udev);
1851 if (udev->state == USB_STATE_SUSPENDED) {
1852 dev_dbg(&udev->dev, "RESUME (wakeup)\n");
1853 /* TRSMRCY = 10 msec */
1855 status = finish_device_resume(udev);
1857 usb_unlock_device(udev);
1862 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
1864 struct usb_hub *hub = usb_get_intfdata (intf);
1865 struct usb_device *hdev = hub->hdev;
1868 /* fail if children aren't already suspended */
1869 for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1870 struct usb_device *udev;
1872 udev = hdev->children [port1-1];
1873 if (udev && (udev->dev.power.power_state.event
1875 #ifdef CONFIG_USB_SUSPEND
1876 || udev->state != USB_STATE_SUSPENDED
1879 dev_dbg(&intf->dev, "port %d nyet suspended\n", port1);
1884 /* "global suspend" of the downstream HC-to-USB interface */
1885 if (!hdev->parent) {
1886 struct usb_bus *bus = hdev->bus;
1888 int status = hcd_bus_suspend (bus);
1891 dev_dbg(&hdev->dev, "'global' suspend %d\n",
1899 /* stop khubd and related activity */
1904 static int hub_resume(struct usb_interface *intf)
1906 struct usb_device *hdev = interface_to_usbdev(intf);
1907 struct usb_hub *hub = usb_get_intfdata (intf);
1910 /* "global resume" of the downstream HC-to-USB interface */
1911 if (!hdev->parent) {
1912 struct usb_bus *bus = hdev->bus;
1914 status = hcd_bus_resume (bus);
1916 dev_dbg(&intf->dev, "'global' resume %d\n",
1923 /* TRSMRCY = 10 msec */
1930 /* REVISIT: this recursion probably shouldn't exist. Remove
1931 * this code sometime, after retesting with different root and
1934 #ifdef CONFIG_USB_SUSPEND
1938 for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1939 struct usb_device *udev;
1940 u16 portstat, portchange;
1942 udev = hdev->children [port1-1];
1943 status = hub_port_status(hub, port1, &portstat, &portchange);
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;
1951 /* let khubd handle disconnects etc */
1956 if (!udev || status < 0)
1958 usb_lock_device(udev);
1959 if (portstat & USB_PORT_STAT_SUSPEND)
1960 status = hub_port_resume(hub, port1, udev);
1962 status = finish_device_resume(udev);
1964 dev_dbg(&intf->dev, "resume port %d --> %d\n",
1966 hub_port_logical_disconnect(hub, port1);
1969 usb_unlock_device(udev);
1976 void usb_suspend_root_hub(struct usb_device *hdev)
1978 struct usb_hub *hub = hdev_to_hub(hdev);
1980 /* This also makes any led blinker stop retriggering. We're called
1981 * from irq, so the blinker might still be scheduled. Caller promises
1982 * that the root hub status URB will be canceled.
1985 mark_quiesced(to_usb_interface(hub->intfdev));
1988 void usb_resume_root_hub(struct usb_device *hdev)
1990 struct usb_hub *hub = hdev_to_hub(hdev);
1992 hub->resume_root_hub = 1;
1997 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
1999 * Between connect detection and reset signaling there must be a delay
2000 * of 100ms at least for debounce and power-settling. The corresponding
2001 * timer shall restart whenever the downstream port detects a disconnect.
2003 * Apparently there are some bluetooth and irda-dongles and a number of
2004 * low-speed devices for which this debounce period may last over a second.
2005 * Not covered by the spec - but easy to deal with.
2007 * This implementation uses a 1500ms total debounce timeout; if the
2008 * connection isn't stable by then it returns -ETIMEDOUT. It checks
2009 * every 25ms for transient disconnects. When the port status has been
2010 * unchanged for 100ms it returns the port status.
2013 #define HUB_DEBOUNCE_TIMEOUT 1500
2014 #define HUB_DEBOUNCE_STEP 25
2015 #define HUB_DEBOUNCE_STABLE 100
2017 static int hub_port_debounce(struct usb_hub *hub, int port1)
2020 int total_time, stable_time = 0;
2021 u16 portchange, portstatus;
2022 unsigned connection = 0xffff;
2024 for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2025 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2029 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2030 (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2031 stable_time += HUB_DEBOUNCE_STEP;
2032 if (stable_time >= HUB_DEBOUNCE_STABLE)
2036 connection = portstatus & USB_PORT_STAT_CONNECTION;
2039 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2040 clear_port_feature(hub->hdev, port1,
2041 USB_PORT_FEAT_C_CONNECTION);
2044 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2046 msleep(HUB_DEBOUNCE_STEP);
2049 dev_dbg (hub->intfdev,
2050 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2051 port1, total_time, stable_time, portstatus);
2053 if (stable_time < HUB_DEBOUNCE_STABLE)
2058 static void ep0_reinit(struct usb_device *udev)
2060 usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2061 usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2062 udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2065 #define usb_sndaddr0pipe() (PIPE_CONTROL << 30)
2066 #define usb_rcvaddr0pipe() ((PIPE_CONTROL << 30) | USB_DIR_IN)
2068 static int hub_set_address(struct usb_device *udev)
2072 if (udev->devnum == 0)
2074 if (udev->state == USB_STATE_ADDRESS)
2076 if (udev->state != USB_STATE_DEFAULT)
2078 retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2079 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2080 NULL, 0, USB_CTRL_SET_TIMEOUT);
2082 usb_set_device_state(udev, USB_STATE_ADDRESS);
2088 /* Reset device, (re)assign address, get device descriptor.
2089 * Device connection must be stable, no more debouncing needed.
2090 * Returns device in USB_STATE_ADDRESS, except on error.
2092 * If this is called for an already-existing device (as part of
2093 * usb_reset_device), the caller must own the device lock. For a
2094 * newly detected device that is not accessible through any global
2095 * pointers, it's not necessary to lock the device.
2098 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2101 static DECLARE_MUTEX(usb_address0_sem);
2103 struct usb_device *hdev = hub->hdev;
2105 unsigned delay = HUB_SHORT_RESET_TIME;
2106 enum usb_device_speed oldspeed = udev->speed;
2108 /* root hub ports have a slightly longer reset period
2109 * (from USB 2.0 spec, section 7.1.7.5)
2111 if (!hdev->parent) {
2112 delay = HUB_ROOT_RESET_TIME;
2113 if (port1 == hdev->bus->otg_port)
2114 hdev->bus->b_hnp_enable = 0;
2117 /* Some low speed devices have problems with the quick delay, so */
2118 /* be a bit pessimistic with those devices. RHbug #23670 */
2119 if (oldspeed == USB_SPEED_LOW)
2120 delay = HUB_LONG_RESET_TIME;
2122 down(&usb_address0_sem);
2124 /* Reset the device; full speed may morph to high speed */
2125 retval = hub_port_reset(hub, port1, udev, delay);
2126 if (retval < 0) /* error or disconnect */
2128 /* success, speed is known */
2131 if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2132 dev_dbg(&udev->dev, "device reset changed speed!\n");
2135 oldspeed = udev->speed;
2137 /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2138 * it's fixed size except for full speed devices.
2140 switch (udev->speed) {
2141 case USB_SPEED_HIGH: /* fixed at 64 */
2142 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2144 case USB_SPEED_FULL: /* 8, 16, 32, or 64 */
2145 /* to determine the ep0 maxpacket size, try to read
2146 * the device descriptor to get bMaxPacketSize0 and
2147 * then correct our initial guess.
2149 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2151 case USB_SPEED_LOW: /* fixed at 8 */
2152 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2158 dev_info (&udev->dev,
2159 "%s %s speed USB device using %s and address %d\n",
2160 (udev->config) ? "reset" : "new",
2161 ({ char *speed; switch (udev->speed) {
2162 case USB_SPEED_LOW: speed = "low"; break;
2163 case USB_SPEED_FULL: speed = "full"; break;
2164 case USB_SPEED_HIGH: speed = "high"; break;
2165 default: speed = "?"; break;
2167 udev->bus->controller->driver->name,
2170 /* Set up TT records, if needed */
2172 udev->tt = hdev->tt;
2173 udev->ttport = hdev->ttport;
2174 } else if (udev->speed != USB_SPEED_HIGH
2175 && hdev->speed == USB_SPEED_HIGH) {
2176 udev->tt = &hub->tt;
2177 udev->ttport = port1;
2180 /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2181 * Because device hardware and firmware is sometimes buggy in
2182 * this area, and this is how Linux has done it for ages.
2183 * Change it cautiously.
2185 * NOTE: If USE_NEW_SCHEME() is true we will start by issuing
2186 * a 64-byte GET_DESCRIPTOR request. This is what Windows does,
2187 * so it may help with some non-standards-compliant devices.
2188 * Otherwise we start with SET_ADDRESS and then try to read the
2189 * first 8 bytes of the device descriptor to get the ep0 maxpacket
2192 for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2193 if (USE_NEW_SCHEME(retry_counter)) {
2194 struct usb_device_descriptor *buf;
2197 #define GET_DESCRIPTOR_BUFSIZE 64
2198 buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2204 /* Use a short timeout the first time through,
2205 * so that recalcitrant full-speed devices with
2206 * 8- or 16-byte ep0-maxpackets won't slow things
2207 * down tremendously by NAKing the unexpectedly
2208 * early status stage. Also, retry on all errors;
2209 * some devices are flakey.
2211 for (j = 0; j < 3; ++j) {
2212 buf->bMaxPacketSize0 = 0;
2213 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2214 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2215 USB_DT_DEVICE << 8, 0,
2216 buf, GET_DESCRIPTOR_BUFSIZE,
2217 (i ? USB_CTRL_GET_TIMEOUT : 1000));
2218 switch (buf->bMaxPacketSize0) {
2219 case 8: case 16: case 32: case 64:
2220 if (buf->bDescriptorType ==
2234 udev->descriptor.bMaxPacketSize0 =
2235 buf->bMaxPacketSize0;
2238 retval = hub_port_reset(hub, port1, udev, delay);
2239 if (retval < 0) /* error or disconnect */
2241 if (oldspeed != udev->speed) {
2243 "device reset changed speed!\n");
2248 dev_err(&udev->dev, "device descriptor "
2249 "read/%s, error %d\n",
2254 #undef GET_DESCRIPTOR_BUFSIZE
2257 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2258 retval = hub_set_address(udev);
2265 "device not accepting address %d, error %d\n",
2266 udev->devnum, retval);
2270 /* cope with hardware quirkiness:
2271 * - let SET_ADDRESS settle, some device hardware wants it
2272 * - read ep0 maxpacket even for high and low speed,
2275 if (USE_NEW_SCHEME(retry_counter))
2278 retval = usb_get_device_descriptor(udev, 8);
2280 dev_err(&udev->dev, "device descriptor "
2281 "read/%s, error %d\n",
2293 i = udev->descriptor.bMaxPacketSize0;
2294 if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2295 if (udev->speed != USB_SPEED_FULL ||
2296 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2297 dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2301 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2302 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2306 retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2307 if (retval < (signed)sizeof(udev->descriptor)) {
2308 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2319 hub_port_disable(hub, port1, 0);
2320 up(&usb_address0_sem);
2325 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2327 struct usb_qualifier_descriptor *qual;
2330 qual = kmalloc (sizeof *qual, SLAB_KERNEL);
2334 status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2335 qual, sizeof *qual);
2336 if (status == sizeof *qual) {
2337 dev_info(&udev->dev, "not running at top speed; "
2338 "connect to a high speed hub\n");
2339 /* hub LEDs are probably harder to miss than syslog */
2340 if (hub->has_indicators) {
2341 hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2342 schedule_work (&hub->leds);
2349 hub_power_remaining (struct usb_hub *hub)
2351 struct usb_device *hdev = hub->hdev;
2355 remaining = hub->power_budget;
2356 if (!remaining) /* self-powered */
2359 for (i = 0; i < hdev->maxchild; i++) {
2360 struct usb_device *udev = hdev->children[i];
2366 /* 100mA per-port ceiling, or 8mA for OTG ports */
2367 if (i != (udev->bus->otg_port - 1) || hdev->parent)
2372 if (udev->actconfig)
2373 delta = udev->actconfig->desc.bMaxPower;
2376 // dev_dbg(&udev->dev, "budgeted %dmA\n", 2 * delta);
2377 if (delta > ceiling)
2378 dev_warn(&udev->dev, "%dmA over %dmA budget!\n",
2379 2 * (delta - ceiling), 2 * ceiling);
2382 if (remaining < 0) {
2383 dev_warn(hub->intfdev,
2384 "%dmA over power budget!\n",
2391 /* Handle physical or logical connection change events.
2392 * This routine is called when:
2393 * a port connection-change occurs;
2394 * a port enable-change occurs (often caused by EMI);
2395 * usb_reset_device() encounters changed descriptors (as from
2396 * a firmware download)
2397 * caller already locked the hub
2399 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2400 u16 portstatus, u16 portchange)
2402 struct usb_device *hdev = hub->hdev;
2403 struct device *hub_dev = hub->intfdev;
2404 u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2408 "port %d, status %04x, change %04x, %s\n",
2409 port1, portstatus, portchange, portspeed (portstatus));
2411 if (hub->has_indicators) {
2412 set_port_led(hub, port1, HUB_LED_AUTO);
2413 hub->indicator[port1-1] = INDICATOR_AUTO;
2416 /* Disconnect any existing devices under this port */
2417 if (hdev->children[port1-1])
2418 usb_disconnect(&hdev->children[port1-1]);
2419 clear_bit(port1, hub->change_bits);
2421 #ifdef CONFIG_USB_OTG
2422 /* during HNP, don't repeat the debounce */
2423 if (hdev->bus->is_b_host)
2424 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2427 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2428 status = hub_port_debounce(hub, port1);
2431 "connect-debounce failed, port %d disabled\n",
2435 portstatus = status;
2438 /* Return now if nothing is connected */
2439 if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2441 /* maybe switch power back on (e.g. root hub was reset) */
2442 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
2443 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2444 set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2446 if (portstatus & USB_PORT_STAT_ENABLE)
2451 #ifdef CONFIG_USB_SUSPEND
2452 /* If something is connected, but the port is suspended, wake it up. */
2453 if (portstatus & USB_PORT_STAT_SUSPEND) {
2454 status = hub_port_resume(hub, port1, NULL);
2457 "can't clear suspend on port %d; %d\n",
2464 for (i = 0; i < SET_CONFIG_TRIES; i++) {
2465 struct usb_device *udev;
2467 /* reallocate for each attempt, since references
2468 * to the previous one can escape in various ways
2470 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2473 "couldn't allocate port %d usb_device\n",
2478 usb_set_device_state(udev, USB_STATE_POWERED);
2479 udev->speed = USB_SPEED_UNKNOWN;
2481 /* set the address */
2482 choose_address(udev);
2483 if (udev->devnum <= 0) {
2484 status = -ENOTCONN; /* Don't retry */
2488 /* reset and get descriptor */
2489 status = hub_port_init(hub, udev, port1, i);
2493 /* consecutive bus-powered hubs aren't reliable; they can
2494 * violate the voltage drop budget. if the new child has
2495 * a "powered" LED, users should notice we didn't enable it
2496 * (without reading syslog), even without per-port LEDs
2499 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2500 && hub->power_budget) {
2503 status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2506 dev_dbg(&udev->dev, "get status %d ?\n", status);
2509 cpu_to_le16s(&devstat);
2510 if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2512 "can't connect bus-powered hub "
2514 if (hub->has_indicators) {
2515 hub->indicator[port1-1] =
2516 INDICATOR_AMBER_BLINK;
2517 schedule_work (&hub->leds);
2519 status = -ENOTCONN; /* Don't retry */
2524 /* check for devices running slower than they could */
2525 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2526 && udev->speed == USB_SPEED_FULL
2527 && highspeed_hubs != 0)
2528 check_highspeed (hub, udev, port1);
2530 /* Store the parent's children[] pointer. At this point
2531 * udev becomes globally accessible, although presumably
2532 * no one will look at it until hdev is unlocked.
2536 /* We mustn't add new devices if the parent hub has
2537 * been disconnected; we would race with the
2538 * recursively_mark_NOTATTACHED() routine.
2540 spin_lock_irq(&device_state_lock);
2541 if (hdev->state == USB_STATE_NOTATTACHED)
2544 hdev->children[port1-1] = udev;
2545 spin_unlock_irq(&device_state_lock);
2547 /* Run it through the hoops (find a driver, etc) */
2549 status = usb_new_device(udev);
2551 spin_lock_irq(&device_state_lock);
2552 hdev->children[port1-1] = NULL;
2553 spin_unlock_irq(&device_state_lock);
2560 status = hub_power_remaining(hub);
2563 "%dmA power budget left\n",
2569 hub_port_disable(hub, port1, 1);
2572 release_address(udev);
2574 if (status == -ENOTCONN)
2579 hub_port_disable(hub, port1, 1);
2582 static void hub_events(void)
2584 struct list_head *tmp;
2585 struct usb_device *hdev;
2586 struct usb_interface *intf;
2587 struct usb_hub *hub;
2588 struct device *hub_dev;
2597 * We restart the list every time to avoid a deadlock with
2598 * deleting hubs downstream from this one. This should be
2599 * safe since we delete the hub from the event list.
2600 * Not the most efficient, but avoids deadlocks.
2604 /* Grab the first entry at the beginning of the list */
2605 spin_lock_irq(&hub_event_lock);
2606 if (list_empty(&hub_event_list)) {
2607 spin_unlock_irq(&hub_event_lock);
2611 tmp = hub_event_list.next;
2614 hub = list_entry(tmp, struct usb_hub, event_list);
2616 intf = to_usb_interface(hub->intfdev);
2617 hub_dev = &intf->dev;
2619 i = hub->resume_root_hub;
2621 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x%s\n",
2622 hdev->state, hub->descriptor
2623 ? hub->descriptor->bNbrPorts
2625 /* NOTE: expects max 15 ports... */
2626 (u16) hub->change_bits[0],
2627 (u16) hub->event_bits[0],
2628 i ? ", resume root" : "");
2631 spin_unlock_irq(&hub_event_lock);
2633 /* Is this is a root hub wanting to reactivate the downstream
2634 * ports? If so, be sure the interface resumes even if its
2635 * stub "device" node was never suspended.
2638 dpm_runtime_resume(&hdev->dev);
2639 dpm_runtime_resume(&intf->dev);
2642 /* Lock the device, then check to see if we were
2643 * disconnected while waiting for the lock to succeed. */
2644 if (locktree(hdev) < 0) {
2648 if (hub != usb_get_intfdata(intf))
2651 /* If the hub has died, clean up after it */
2652 if (hdev->state == USB_STATE_NOTATTACHED) {
2653 hub_pre_reset(hub, 0);
2657 /* If this is an inactive or suspended hub, do nothing */
2662 dev_dbg (hub_dev, "resetting for error %d\n",
2665 ret = usb_reset_device(hdev);
2668 "error resetting hub: %d\n", ret);
2676 /* deal with port status changes */
2677 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2678 if (test_bit(i, hub->busy_bits))
2680 connect_change = test_bit(i, hub->change_bits);
2681 if (!test_and_clear_bit(i, hub->event_bits) &&
2682 !connect_change && !hub->activating)
2685 ret = hub_port_status(hub, i,
2686 &portstatus, &portchange);
2690 if (hub->activating && !hdev->children[i-1] &&
2692 USB_PORT_STAT_CONNECTION))
2695 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2696 clear_port_feature(hdev, i,
2697 USB_PORT_FEAT_C_CONNECTION);
2701 if (portchange & USB_PORT_STAT_C_ENABLE) {
2702 if (!connect_change)
2704 "port %d enable change, "
2707 clear_port_feature(hdev, i,
2708 USB_PORT_FEAT_C_ENABLE);
2711 * EM interference sometimes causes badly
2712 * shielded USB devices to be shutdown by
2713 * the hub, this hack enables them again.
2714 * Works at least with mouse driver.
2716 if (!(portstatus & USB_PORT_STAT_ENABLE)
2718 && hdev->children[i-1]) {
2721 "disabled by hub (EMI?), "
2728 if (portchange & USB_PORT_STAT_C_SUSPEND) {
2729 clear_port_feature(hdev, i,
2730 USB_PORT_FEAT_C_SUSPEND);
2731 if (hdev->children[i-1]) {
2732 ret = remote_wakeup(hdev->
2738 hub_port_disable(hub, i, 1);
2741 "resume on port %d, status %d\n",
2745 if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2747 "over-current change on port %d\n",
2749 clear_port_feature(hdev, i,
2750 USB_PORT_FEAT_C_OVER_CURRENT);
2754 if (portchange & USB_PORT_STAT_C_RESET) {
2756 "reset change on port %d\n",
2758 clear_port_feature(hdev, i,
2759 USB_PORT_FEAT_C_RESET);
2763 hub_port_connect_change(hub, i,
2764 portstatus, portchange);
2767 /* deal with hub status changes */
2768 if (test_and_clear_bit(0, hub->event_bits) == 0)
2770 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2771 dev_err (hub_dev, "get_hub_status failed\n");
2773 if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2774 dev_dbg (hub_dev, "power change\n");
2775 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2777 if (hubchange & HUB_CHANGE_OVERCURRENT) {
2778 dev_dbg (hub_dev, "overcurrent change\n");
2779 msleep(500); /* Cool down */
2780 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2785 hub->activating = 0;
2787 /* If this is a root hub, tell the HCD it's okay to
2788 * re-enable port-change interrupts now. */
2790 usb_enable_root_hub_irq(hdev->bus);
2793 usb_unlock_device(hdev);
2796 } /* end while (1) */
2799 static int hub_thread(void *__unused)
2803 wait_event_interruptible(khubd_wait,
2804 !list_empty(&hub_event_list) ||
2805 kthread_should_stop());
2807 } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2809 pr_debug("%s: khubd exiting\n", usbcore_name);
2813 static struct usb_device_id hub_id_table [] = {
2814 { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2815 .bDeviceClass = USB_CLASS_HUB},
2816 { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2817 .bInterfaceClass = USB_CLASS_HUB},
2818 { } /* Terminating entry */
2821 MODULE_DEVICE_TABLE (usb, hub_id_table);
2823 static struct usb_driver hub_driver = {
2826 .disconnect = hub_disconnect,
2827 .suspend = hub_suspend,
2828 .resume = hub_resume,
2830 .id_table = hub_id_table,
2833 int usb_hub_init(void)
2835 if (usb_register(&hub_driver) < 0) {
2836 printk(KERN_ERR "%s: can't register hub driver\n",
2841 khubd_task = kthread_run(hub_thread, NULL, "khubd");
2842 if (!IS_ERR(khubd_task))
2845 /* Fall through if kernel_thread failed */
2846 usb_deregister(&hub_driver);
2847 printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2852 void usb_hub_cleanup(void)
2854 kthread_stop(khubd_task);
2857 * Hub resources are freed for us by usb_deregister. It calls
2858 * usb_driver_purge on every device which in turn calls that
2859 * devices disconnect function if it is using this driver.
2860 * The hub_disconnect function takes care of releasing the
2861 * individual hub resources. -greg
2863 usb_deregister(&hub_driver);
2864 } /* usb_hub_cleanup() */
2866 static int config_descriptors_changed(struct usb_device *udev)
2870 struct usb_config_descriptor *buf;
2872 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2873 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2874 len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2876 buf = kmalloc (len, SLAB_KERNEL);
2878 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2879 /* assume the worst */
2882 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2884 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2886 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2888 if (length < old_length) {
2889 dev_dbg(&udev->dev, "config index %d, error %d\n",
2893 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2895 dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2896 index, buf->bConfigurationValue);
2901 return index != udev->descriptor.bNumConfigurations;
2905 * usb_reset_device - perform a USB port reset to reinitialize a device
2906 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2908 * WARNING - don't reset any device unless drivers for all of its
2909 * interfaces are expecting that reset! Maybe some driver->reset()
2910 * method should eventually help ensure sufficient cooperation.
2912 * Do a port reset, reassign the device's address, and establish its
2913 * former operating configuration. If the reset fails, or the device's
2914 * descriptors change from their values before the reset, or the original
2915 * configuration and altsettings cannot be restored, a flag will be set
2916 * telling khubd to pretend the device has been disconnected and then
2917 * re-connected. All drivers will be unbound, and the device will be
2918 * re-enumerated and probed all over again.
2920 * Returns 0 if the reset succeeded, -ENODEV if the device has been
2921 * flagged for logical disconnection, or some other negative error code
2922 * if the reset wasn't even attempted.
2924 * The caller must own the device lock. For example, it's safe to use
2925 * this from a driver probe() routine after downloading new firmware.
2926 * For calls that might not occur during probe(), drivers should lock
2927 * the device using usb_lock_device_for_reset().
2929 int usb_reset_device(struct usb_device *udev)
2931 struct usb_device *parent_hdev = udev->parent;
2932 struct usb_hub *parent_hub;
2933 struct usb_device_descriptor descriptor = udev->descriptor;
2934 struct usb_hub *hub = NULL;
2935 int i, ret = 0, port1 = -1;
2937 if (udev->state == USB_STATE_NOTATTACHED ||
2938 udev->state == USB_STATE_SUSPENDED) {
2939 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2945 /* this requires hcd-specific logic; see OHCI hc_restart() */
2946 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2950 for (i = 0; i < parent_hdev->maxchild; i++)
2951 if (parent_hdev->children[i] == udev) {
2957 /* If this ever happens, it's very bad */
2958 dev_err(&udev->dev, "Can't locate device's port!\n");
2961 parent_hub = hdev_to_hub(parent_hdev);
2963 /* If we're resetting an active hub, take some special actions */
2964 if (udev->actconfig &&
2965 udev->actconfig->interface[0]->dev.driver ==
2966 &hub_driver.driver &&
2967 (hub = hdev_to_hub(udev)) != NULL) {
2968 hub_pre_reset(hub, 0);
2971 set_bit(port1, parent_hub->busy_bits);
2972 for (i = 0; i < SET_CONFIG_TRIES; ++i) {
2974 /* ep0 maxpacket size may change; let the HCD know about it.
2975 * Other endpoints will be handled by re-enumeration. */
2977 ret = hub_port_init(parent_hub, udev, port1, i);
2981 clear_bit(port1, parent_hub->busy_bits);
2985 /* Device might have changed firmware (DFU or similar) */
2986 if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
2987 || config_descriptors_changed (udev)) {
2988 dev_info(&udev->dev, "device firmware changed\n");
2989 udev->descriptor = descriptor; /* for disconnect() calls */
2993 if (!udev->actconfig)
2996 ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2997 USB_REQ_SET_CONFIGURATION, 0,
2998 udev->actconfig->desc.bConfigurationValue, 0,
2999 NULL, 0, USB_CTRL_SET_TIMEOUT);
3002 "can't restore configuration #%d (error=%d)\n",
3003 udev->actconfig->desc.bConfigurationValue, ret);
3006 usb_set_device_state(udev, USB_STATE_CONFIGURED);
3008 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3009 struct usb_interface *intf = udev->actconfig->interface[i];
3010 struct usb_interface_descriptor *desc;
3012 /* set_interface resets host side toggle even
3013 * for altsetting zero. the interface may have no driver.
3015 desc = &intf->cur_altsetting->desc;
3016 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3017 desc->bAlternateSetting);
3019 dev_err(&udev->dev, "failed to restore interface %d "
3020 "altsetting %d (error=%d)\n",
3021 desc->bInterfaceNumber,
3022 desc->bAlternateSetting,
3030 hub_post_reset(hub);
3034 hub_port_logical_disconnect(parent_hub, port1);