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/ioctl.h>
20 #include <linux/usb.h>
21 #include <linux/usbdevice_fs.h>
22 #include <linux/usb/hcd.h>
23 #include <linux/usb/quirks.h>
24 #include <linux/kthread.h>
25 #include <linux/mutex.h>
26 #include <linux/freezer.h>
27 #include <linux/random.h>
29 #include <asm/uaccess.h>
30 #include <asm/byteorder.h>
34 /* if we are in debug mode, always announce new devices */
36 #ifndef CONFIG_USB_ANNOUNCE_NEW_DEVICES
37 #define CONFIG_USB_ANNOUNCE_NEW_DEVICES
42 struct device *intfdev; /* the "interface" device */
43 struct usb_device *hdev;
45 struct urb *urb; /* for interrupt polling pipe */
47 /* buffer for urb ... with extra space in case of babble */
50 struct usb_hub_status hub;
51 struct usb_port_status port;
52 } *status; /* buffer for status reports */
53 struct mutex status_mutex; /* for the status buffer */
55 int error; /* last reported error */
56 int nerrors; /* track consecutive errors */
58 struct list_head event_list; /* hubs w/data or errs ready */
59 unsigned long event_bits[1]; /* status change bitmask */
60 unsigned long change_bits[1]; /* ports with logical connect
62 unsigned long busy_bits[1]; /* ports being reset or
64 unsigned long removed_bits[1]; /* ports with a "removed"
66 #if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
67 #error event_bits[] is too short!
70 struct usb_hub_descriptor *descriptor; /* class descriptor */
71 struct usb_tt tt; /* Transaction Translator */
73 unsigned mA_per_port; /* current for each child */
75 unsigned limited_power:1;
77 unsigned disconnected:1;
79 unsigned has_indicators:1;
80 u8 indicator[USB_MAXCHILDREN];
81 struct delayed_work leds;
82 struct delayed_work init_work;
86 static inline int hub_is_superspeed(struct usb_device *hdev)
88 return (hdev->descriptor.bDeviceProtocol == 3);
91 /* Protect struct usb_device->state and ->children members
92 * Note: Both are also protected by ->dev.sem, except that ->state can
93 * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
94 static DEFINE_SPINLOCK(device_state_lock);
96 /* khubd's worklist and its lock */
97 static DEFINE_SPINLOCK(hub_event_lock);
98 static LIST_HEAD(hub_event_list); /* List of hubs needing servicing */
101 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
103 static struct task_struct *khubd_task;
105 /* cycle leds on hubs that aren't blinking for attention */
106 static int blinkenlights = 0;
107 module_param (blinkenlights, bool, S_IRUGO);
108 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
111 * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
112 * 10 seconds to send reply for the initial 64-byte descriptor request.
114 /* define initial 64-byte descriptor request timeout in milliseconds */
115 static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
116 module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
117 MODULE_PARM_DESC(initial_descriptor_timeout,
118 "initial 64-byte descriptor request timeout in milliseconds "
119 "(default 5000 - 5.0 seconds)");
122 * As of 2.6.10 we introduce a new USB device initialization scheme which
123 * closely resembles the way Windows works. Hopefully it will be compatible
124 * with a wider range of devices than the old scheme. However some previously
125 * working devices may start giving rise to "device not accepting address"
126 * errors; if that happens the user can try the old scheme by adjusting the
127 * following module parameters.
129 * For maximum flexibility there are two boolean parameters to control the
130 * hub driver's behavior. On the first initialization attempt, if the
131 * "old_scheme_first" parameter is set then the old scheme will be used,
132 * otherwise the new scheme is used. If that fails and "use_both_schemes"
133 * is set, then the driver will make another attempt, using the other scheme.
135 static int old_scheme_first = 0;
136 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
137 MODULE_PARM_DESC(old_scheme_first,
138 "start with the old device initialization scheme");
140 static int use_both_schemes = 1;
141 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
142 MODULE_PARM_DESC(use_both_schemes,
143 "try the other device initialization scheme if the "
146 /* Mutual exclusion for EHCI CF initialization. This interferes with
147 * port reset on some companion controllers.
149 DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
150 EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
152 #define HUB_DEBOUNCE_TIMEOUT 1500
153 #define HUB_DEBOUNCE_STEP 25
154 #define HUB_DEBOUNCE_STABLE 100
157 static int usb_reset_and_verify_device(struct usb_device *udev);
159 static inline char *portspeed(struct usb_hub *hub, int portstatus)
161 if (hub_is_superspeed(hub->hdev))
163 if (portstatus & USB_PORT_STAT_HIGH_SPEED)
165 else if (portstatus & USB_PORT_STAT_LOW_SPEED)
171 /* Note that hdev or one of its children must be locked! */
172 static struct usb_hub *hdev_to_hub(struct usb_device *hdev)
174 if (!hdev || !hdev->actconfig)
176 return usb_get_intfdata(hdev->actconfig->interface[0]);
179 /* USB 2.0 spec Section 11.24.4.5 */
180 static int get_hub_descriptor(struct usb_device *hdev, void *data)
185 if (hub_is_superspeed(hdev)) {
186 dtype = USB_DT_SS_HUB;
187 size = USB_DT_SS_HUB_SIZE;
190 size = sizeof(struct usb_hub_descriptor);
193 for (i = 0; i < 3; i++) {
194 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
195 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
196 dtype << 8, 0, data, size,
197 USB_CTRL_GET_TIMEOUT);
198 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
205 * USB 2.0 spec Section 11.24.2.1
207 static int clear_hub_feature(struct usb_device *hdev, int feature)
209 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
210 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
214 * USB 2.0 spec Section 11.24.2.2
216 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
218 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
219 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
224 * USB 2.0 spec Section 11.24.2.13
226 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
228 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
229 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
234 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
235 * for info about using port indicators
237 static void set_port_led(
243 int status = set_port_feature(hub->hdev, (selector << 8) | port1,
244 USB_PORT_FEAT_INDICATOR);
246 dev_dbg (hub->intfdev,
247 "port %d indicator %s status %d\n",
249 ({ char *s; switch (selector) {
250 case HUB_LED_AMBER: s = "amber"; break;
251 case HUB_LED_GREEN: s = "green"; break;
252 case HUB_LED_OFF: s = "off"; break;
253 case HUB_LED_AUTO: s = "auto"; break;
254 default: s = "??"; break;
259 #define LED_CYCLE_PERIOD ((2*HZ)/3)
261 static void led_work (struct work_struct *work)
263 struct usb_hub *hub =
264 container_of(work, struct usb_hub, leds.work);
265 struct usb_device *hdev = hub->hdev;
267 unsigned changed = 0;
270 if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
273 for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
274 unsigned selector, mode;
276 /* 30%-50% duty cycle */
278 switch (hub->indicator[i]) {
280 case INDICATOR_CYCLE:
282 selector = HUB_LED_AUTO;
283 mode = INDICATOR_AUTO;
285 /* blinking green = sw attention */
286 case INDICATOR_GREEN_BLINK:
287 selector = HUB_LED_GREEN;
288 mode = INDICATOR_GREEN_BLINK_OFF;
290 case INDICATOR_GREEN_BLINK_OFF:
291 selector = HUB_LED_OFF;
292 mode = INDICATOR_GREEN_BLINK;
294 /* blinking amber = hw attention */
295 case INDICATOR_AMBER_BLINK:
296 selector = HUB_LED_AMBER;
297 mode = INDICATOR_AMBER_BLINK_OFF;
299 case INDICATOR_AMBER_BLINK_OFF:
300 selector = HUB_LED_OFF;
301 mode = INDICATOR_AMBER_BLINK;
303 /* blink green/amber = reserved */
304 case INDICATOR_ALT_BLINK:
305 selector = HUB_LED_GREEN;
306 mode = INDICATOR_ALT_BLINK_OFF;
308 case INDICATOR_ALT_BLINK_OFF:
309 selector = HUB_LED_AMBER;
310 mode = INDICATOR_ALT_BLINK;
315 if (selector != HUB_LED_AUTO)
317 set_port_led(hub, i + 1, selector);
318 hub->indicator[i] = mode;
320 if (!changed && blinkenlights) {
322 cursor %= hub->descriptor->bNbrPorts;
323 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
324 hub->indicator[cursor] = INDICATOR_CYCLE;
328 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
331 /* use a short timeout for hub/port status fetches */
332 #define USB_STS_TIMEOUT 1000
333 #define USB_STS_RETRIES 5
336 * USB 2.0 spec Section 11.24.2.6
338 static int get_hub_status(struct usb_device *hdev,
339 struct usb_hub_status *data)
341 int i, status = -ETIMEDOUT;
343 for (i = 0; i < USB_STS_RETRIES &&
344 (status == -ETIMEDOUT || status == -EPIPE); i++) {
345 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
346 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
347 data, sizeof(*data), USB_STS_TIMEOUT);
353 * USB 2.0 spec Section 11.24.2.7
355 static int get_port_status(struct usb_device *hdev, int port1,
356 struct usb_port_status *data)
358 int i, status = -ETIMEDOUT;
360 for (i = 0; i < USB_STS_RETRIES &&
361 (status == -ETIMEDOUT || status == -EPIPE); i++) {
362 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
363 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
364 data, sizeof(*data), USB_STS_TIMEOUT);
369 static int hub_port_status(struct usb_hub *hub, int port1,
370 u16 *status, u16 *change)
374 mutex_lock(&hub->status_mutex);
375 ret = get_port_status(hub->hdev, port1, &hub->status->port);
377 dev_err(hub->intfdev,
378 "%s failed (err = %d)\n", __func__, ret);
382 *status = le16_to_cpu(hub->status->port.wPortStatus);
383 *change = le16_to_cpu(hub->status->port.wPortChange);
387 mutex_unlock(&hub->status_mutex);
391 static void kick_khubd(struct usb_hub *hub)
395 spin_lock_irqsave(&hub_event_lock, flags);
396 if (!hub->disconnected && list_empty(&hub->event_list)) {
397 list_add_tail(&hub->event_list, &hub_event_list);
399 /* Suppress autosuspend until khubd runs */
400 usb_autopm_get_interface_no_resume(
401 to_usb_interface(hub->intfdev));
402 wake_up(&khubd_wait);
404 spin_unlock_irqrestore(&hub_event_lock, flags);
407 void usb_kick_khubd(struct usb_device *hdev)
409 struct usb_hub *hub = hdev_to_hub(hdev);
416 /* completion function, fires on port status changes and various faults */
417 static void hub_irq(struct urb *urb)
419 struct usb_hub *hub = urb->context;
420 int status = urb->status;
425 case -ENOENT: /* synchronous unlink */
426 case -ECONNRESET: /* async unlink */
427 case -ESHUTDOWN: /* hardware going away */
430 default: /* presumably an error */
431 /* Cause a hub reset after 10 consecutive errors */
432 dev_dbg (hub->intfdev, "transfer --> %d\n", status);
433 if ((++hub->nerrors < 10) || hub->error)
438 /* let khubd handle things */
439 case 0: /* we got data: port status changed */
441 for (i = 0; i < urb->actual_length; ++i)
442 bits |= ((unsigned long) ((*hub->buffer)[i]))
444 hub->event_bits[0] = bits;
450 /* Something happened, let khubd figure it out */
457 if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
458 && status != -ENODEV && status != -EPERM)
459 dev_err (hub->intfdev, "resubmit --> %d\n", status);
462 /* USB 2.0 spec Section 11.24.2.3 */
464 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
466 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
467 HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
472 * enumeration blocks khubd for a long time. we use keventd instead, since
473 * long blocking there is the exception, not the rule. accordingly, HCDs
474 * talking to TTs must queue control transfers (not just bulk and iso), so
475 * both can talk to the same hub concurrently.
477 static void hub_tt_work(struct work_struct *work)
479 struct usb_hub *hub =
480 container_of(work, struct usb_hub, tt.clear_work);
484 spin_lock_irqsave (&hub->tt.lock, flags);
485 while (--limit && !list_empty (&hub->tt.clear_list)) {
486 struct list_head *next;
487 struct usb_tt_clear *clear;
488 struct usb_device *hdev = hub->hdev;
489 const struct hc_driver *drv;
492 next = hub->tt.clear_list.next;
493 clear = list_entry (next, struct usb_tt_clear, clear_list);
494 list_del (&clear->clear_list);
496 /* drop lock so HCD can concurrently report other TT errors */
497 spin_unlock_irqrestore (&hub->tt.lock, flags);
498 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
501 "clear tt %d (%04x) error %d\n",
502 clear->tt, clear->devinfo, status);
504 /* Tell the HCD, even if the operation failed */
505 drv = clear->hcd->driver;
506 if (drv->clear_tt_buffer_complete)
507 (drv->clear_tt_buffer_complete)(clear->hcd, clear->ep);
510 spin_lock_irqsave(&hub->tt.lock, flags);
512 spin_unlock_irqrestore (&hub->tt.lock, flags);
516 * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
517 * @urb: an URB associated with the failed or incomplete split transaction
519 * High speed HCDs use this to tell the hub driver that some split control or
520 * bulk transaction failed in a way that requires clearing internal state of
521 * a transaction translator. This is normally detected (and reported) from
524 * It may not be possible for that hub to handle additional full (or low)
525 * speed transactions until that state is fully cleared out.
527 int usb_hub_clear_tt_buffer(struct urb *urb)
529 struct usb_device *udev = urb->dev;
530 int pipe = urb->pipe;
531 struct usb_tt *tt = udev->tt;
533 struct usb_tt_clear *clear;
535 /* we've got to cope with an arbitrary number of pending TT clears,
536 * since each TT has "at least two" buffers that can need it (and
537 * there can be many TTs per hub). even if they're uncommon.
539 if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) {
540 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
541 /* FIXME recover somehow ... RESET_TT? */
545 /* info that CLEAR_TT_BUFFER needs */
546 clear->tt = tt->multi ? udev->ttport : 1;
547 clear->devinfo = usb_pipeendpoint (pipe);
548 clear->devinfo |= udev->devnum << 4;
549 clear->devinfo |= usb_pipecontrol (pipe)
550 ? (USB_ENDPOINT_XFER_CONTROL << 11)
551 : (USB_ENDPOINT_XFER_BULK << 11);
552 if (usb_pipein (pipe))
553 clear->devinfo |= 1 << 15;
555 /* info for completion callback */
556 clear->hcd = bus_to_hcd(udev->bus);
559 /* tell keventd to clear state for this TT */
560 spin_lock_irqsave (&tt->lock, flags);
561 list_add_tail (&clear->clear_list, &tt->clear_list);
562 schedule_work(&tt->clear_work);
563 spin_unlock_irqrestore (&tt->lock, flags);
566 EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer);
568 /* If do_delay is false, return the number of milliseconds the caller
571 static unsigned hub_power_on(struct usb_hub *hub, bool do_delay)
574 unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
576 u16 wHubCharacteristics =
577 le16_to_cpu(hub->descriptor->wHubCharacteristics);
579 /* Enable power on each port. Some hubs have reserved values
580 * of LPSM (> 2) in their descriptors, even though they are
581 * USB 2.0 hubs. Some hubs do not implement port-power switching
582 * but only emulate it. In all cases, the ports won't work
583 * unless we send these messages to the hub.
585 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
586 dev_dbg(hub->intfdev, "enabling power on all ports\n");
588 dev_dbg(hub->intfdev, "trying to enable port power on "
589 "non-switchable hub\n");
590 for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
591 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
593 /* Wait at least 100 msec for power to become stable */
594 delay = max(pgood_delay, (unsigned) 100);
600 static int hub_hub_status(struct usb_hub *hub,
601 u16 *status, u16 *change)
605 mutex_lock(&hub->status_mutex);
606 ret = get_hub_status(hub->hdev, &hub->status->hub);
608 dev_err (hub->intfdev,
609 "%s failed (err = %d)\n", __func__, ret);
611 *status = le16_to_cpu(hub->status->hub.wHubStatus);
612 *change = le16_to_cpu(hub->status->hub.wHubChange);
615 mutex_unlock(&hub->status_mutex);
619 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
621 struct usb_device *hdev = hub->hdev;
624 if (hdev->children[port1-1] && set_state)
625 usb_set_device_state(hdev->children[port1-1],
626 USB_STATE_NOTATTACHED);
627 if (!hub->error && !hub_is_superspeed(hub->hdev))
628 ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
630 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
636 * Disable a port and mark a logical connect-change event, so that some
637 * time later khubd will disconnect() any existing usb_device on the port
638 * and will re-enumerate if there actually is a device attached.
640 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
642 dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
643 hub_port_disable(hub, port1, 1);
645 /* FIXME let caller ask to power down the port:
646 * - some devices won't enumerate without a VBUS power cycle
647 * - SRP saves power that way
648 * - ... new call, TBD ...
649 * That's easy if this hub can switch power per-port, and
650 * khubd reactivates the port later (timer, SRP, etc).
651 * Powerdown must be optional, because of reset/DFU.
654 set_bit(port1, hub->change_bits);
659 * usb_remove_device - disable a device's port on its parent hub
660 * @udev: device to be disabled and removed
661 * Context: @udev locked, must be able to sleep.
663 * After @udev's port has been disabled, khubd is notified and it will
664 * see that the device has been disconnected. When the device is
665 * physically unplugged and something is plugged in, the events will
666 * be received and processed normally.
668 int usb_remove_device(struct usb_device *udev)
671 struct usb_interface *intf;
673 if (!udev->parent) /* Can't remove a root hub */
675 hub = hdev_to_hub(udev->parent);
676 intf = to_usb_interface(hub->intfdev);
678 usb_autopm_get_interface(intf);
679 set_bit(udev->portnum, hub->removed_bits);
680 hub_port_logical_disconnect(hub, udev->portnum);
681 usb_autopm_put_interface(intf);
685 enum hub_activation_type {
686 HUB_INIT, HUB_INIT2, HUB_INIT3, /* INITs must come first */
687 HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
690 static void hub_init_func2(struct work_struct *ws);
691 static void hub_init_func3(struct work_struct *ws);
693 static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
695 struct usb_device *hdev = hub->hdev;
700 bool need_debounce_delay = false;
703 /* Continue a partial initialization */
704 if (type == HUB_INIT2)
706 if (type == HUB_INIT3)
709 /* The superspeed hub except for root hub has to use Hub Depth
710 * value as an offset into the route string to locate the bits
711 * it uses to determine the downstream port number. So hub driver
712 * should send a set hub depth request to superspeed hub after
713 * the superspeed hub is set configuration in initialization or
716 * After a resume, port power should still be on.
717 * For any other type of activation, turn it on.
719 if (type != HUB_RESUME) {
720 if (hdev->parent && hub_is_superspeed(hdev)) {
721 ret = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
722 HUB_SET_DEPTH, USB_RT_HUB,
723 hdev->level - 1, 0, NULL, 0,
724 USB_CTRL_SET_TIMEOUT);
726 dev_err(hub->intfdev,
727 "set hub depth failed\n");
730 /* Speed up system boot by using a delayed_work for the
731 * hub's initial power-up delays. This is pretty awkward
732 * and the implementation looks like a home-brewed sort of
733 * setjmp/longjmp, but it saves at least 100 ms for each
734 * root hub (assuming usbcore is compiled into the kernel
735 * rather than as a module). It adds up.
737 * This can't be done for HUB_RESUME or HUB_RESET_RESUME
738 * because for those activation types the ports have to be
739 * operational when we return. In theory this could be done
740 * for HUB_POST_RESET, but it's easier not to.
742 if (type == HUB_INIT) {
743 delay = hub_power_on(hub, false);
744 PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func2);
745 schedule_delayed_work(&hub->init_work,
746 msecs_to_jiffies(delay));
748 /* Suppress autosuspend until init is done */
749 usb_autopm_get_interface_no_resume(
750 to_usb_interface(hub->intfdev));
751 return; /* Continues at init2: below */
752 } else if (type == HUB_RESET_RESUME) {
753 /* The internal host controller state for the hub device
754 * may be gone after a host power loss on system resume.
755 * Update the device's info so the HW knows it's a hub.
757 hcd = bus_to_hcd(hdev->bus);
758 if (hcd->driver->update_hub_device) {
759 ret = hcd->driver->update_hub_device(hcd, hdev,
762 dev_err(hub->intfdev, "Host not "
763 "accepting hub info "
765 dev_err(hub->intfdev, "LS/FS devices "
766 "and hubs may not work "
767 "under this hub\n.");
770 hub_power_on(hub, true);
772 hub_power_on(hub, true);
777 /* Check each port and set hub->change_bits to let khubd know
778 * which ports need attention.
780 for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
781 struct usb_device *udev = hdev->children[port1-1];
782 u16 portstatus, portchange;
784 portstatus = portchange = 0;
785 status = hub_port_status(hub, port1, &portstatus, &portchange);
786 if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
787 dev_dbg(hub->intfdev,
788 "port %d: status %04x change %04x\n",
789 port1, portstatus, portchange);
791 /* After anything other than HUB_RESUME (i.e., initialization
792 * or any sort of reset), every port should be disabled.
793 * Unconnected ports should likewise be disabled (paranoia),
794 * and so should ports for which we have no usb_device.
796 if ((portstatus & USB_PORT_STAT_ENABLE) && (
797 type != HUB_RESUME ||
798 !(portstatus & USB_PORT_STAT_CONNECTION) ||
800 udev->state == USB_STATE_NOTATTACHED)) {
802 * USB3 protocol ports will automatically transition
803 * to Enabled state when detect an USB3.0 device attach.
804 * Do not disable USB3 protocol ports.
806 if (!hub_is_superspeed(hdev)) {
807 clear_port_feature(hdev, port1,
808 USB_PORT_FEAT_ENABLE);
809 portstatus &= ~USB_PORT_STAT_ENABLE;
811 /* Pretend that power was lost for USB3 devs */
812 portstatus &= ~USB_PORT_STAT_ENABLE;
816 /* Clear status-change flags; we'll debounce later */
817 if (portchange & USB_PORT_STAT_C_CONNECTION) {
818 need_debounce_delay = true;
819 clear_port_feature(hub->hdev, port1,
820 USB_PORT_FEAT_C_CONNECTION);
822 if (portchange & USB_PORT_STAT_C_ENABLE) {
823 need_debounce_delay = true;
824 clear_port_feature(hub->hdev, port1,
825 USB_PORT_FEAT_C_ENABLE);
827 if (portchange & USB_PORT_STAT_C_LINK_STATE) {
828 need_debounce_delay = true;
829 clear_port_feature(hub->hdev, port1,
830 USB_PORT_FEAT_C_PORT_LINK_STATE);
833 if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
834 hub_is_superspeed(hub->hdev)) {
835 need_debounce_delay = true;
836 clear_port_feature(hub->hdev, port1,
837 USB_PORT_FEAT_C_BH_PORT_RESET);
839 /* We can forget about a "removed" device when there's a
840 * physical disconnect or the connect status changes.
842 if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
843 (portchange & USB_PORT_STAT_C_CONNECTION))
844 clear_bit(port1, hub->removed_bits);
846 if (!udev || udev->state == USB_STATE_NOTATTACHED) {
847 /* Tell khubd to disconnect the device or
848 * check for a new connection
850 if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
851 set_bit(port1, hub->change_bits);
853 } else if (portstatus & USB_PORT_STAT_ENABLE) {
854 /* The power session apparently survived the resume.
855 * If there was an overcurrent or suspend change
856 * (i.e., remote wakeup request), have khubd
860 set_bit(port1, hub->change_bits);
862 } else if (udev->persist_enabled) {
864 udev->reset_resume = 1;
866 set_bit(port1, hub->change_bits);
869 /* The power session is gone; tell khubd */
870 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
871 set_bit(port1, hub->change_bits);
875 /* If no port-status-change flags were set, we don't need any
876 * debouncing. If flags were set we can try to debounce the
877 * ports all at once right now, instead of letting khubd do them
878 * one at a time later on.
880 * If any port-status changes do occur during this delay, khubd
881 * will see them later and handle them normally.
883 if (need_debounce_delay) {
884 delay = HUB_DEBOUNCE_STABLE;
886 /* Don't do a long sleep inside a workqueue routine */
887 if (type == HUB_INIT2) {
888 PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func3);
889 schedule_delayed_work(&hub->init_work,
890 msecs_to_jiffies(delay));
891 return; /* Continues at init3: below */
899 status = usb_submit_urb(hub->urb, GFP_NOIO);
901 dev_err(hub->intfdev, "activate --> %d\n", status);
902 if (hub->has_indicators && blinkenlights)
903 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
905 /* Scan all ports that need attention */
908 /* Allow autosuspend if it was suppressed */
909 if (type <= HUB_INIT3)
910 usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
913 /* Implement the continuations for the delays above */
914 static void hub_init_func2(struct work_struct *ws)
916 struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
918 hub_activate(hub, HUB_INIT2);
921 static void hub_init_func3(struct work_struct *ws)
923 struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
925 hub_activate(hub, HUB_INIT3);
928 enum hub_quiescing_type {
929 HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
932 static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
934 struct usb_device *hdev = hub->hdev;
937 cancel_delayed_work_sync(&hub->init_work);
939 /* khubd and related activity won't re-trigger */
942 if (type != HUB_SUSPEND) {
943 /* Disconnect all the children */
944 for (i = 0; i < hdev->maxchild; ++i) {
945 if (hdev->children[i])
946 usb_disconnect(&hdev->children[i]);
950 /* Stop khubd and related activity */
951 usb_kill_urb(hub->urb);
952 if (hub->has_indicators)
953 cancel_delayed_work_sync(&hub->leds);
955 cancel_work_sync(&hub->tt.clear_work);
958 /* caller has locked the hub device */
959 static int hub_pre_reset(struct usb_interface *intf)
961 struct usb_hub *hub = usb_get_intfdata(intf);
963 hub_quiesce(hub, HUB_PRE_RESET);
967 /* caller has locked the hub device */
968 static int hub_post_reset(struct usb_interface *intf)
970 struct usb_hub *hub = usb_get_intfdata(intf);
972 hub_activate(hub, HUB_POST_RESET);
976 static int hub_configure(struct usb_hub *hub,
977 struct usb_endpoint_descriptor *endpoint)
980 struct usb_device *hdev = hub->hdev;
981 struct device *hub_dev = hub->intfdev;
982 u16 hubstatus, hubchange;
983 u16 wHubCharacteristics;
986 char *message = "out of memory";
988 hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
994 hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
999 mutex_init(&hub->status_mutex);
1001 hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
1002 if (!hub->descriptor) {
1007 /* Request the entire hub descriptor.
1008 * hub->descriptor can handle USB_MAXCHILDREN ports,
1009 * but the hub can/will return fewer bytes here.
1011 ret = get_hub_descriptor(hdev, hub->descriptor);
1013 message = "can't read hub descriptor";
1015 } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
1016 message = "hub has too many ports!";
1021 hdev->maxchild = hub->descriptor->bNbrPorts;
1022 dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
1023 (hdev->maxchild == 1) ? "" : "s");
1025 hub->port_owners = kzalloc(hdev->maxchild * sizeof(void *), GFP_KERNEL);
1026 if (!hub->port_owners) {
1031 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
1033 /* FIXME for USB 3.0, skip for now */
1034 if ((wHubCharacteristics & HUB_CHAR_COMPOUND) &&
1035 !(hub_is_superspeed(hdev))) {
1037 char portstr [USB_MAXCHILDREN + 1];
1039 for (i = 0; i < hdev->maxchild; i++)
1040 portstr[i] = hub->descriptor->u.hs.DeviceRemovable
1041 [((i + 1) / 8)] & (1 << ((i + 1) % 8))
1043 portstr[hdev->maxchild] = 0;
1044 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
1046 dev_dbg(hub_dev, "standalone hub\n");
1048 switch (wHubCharacteristics & HUB_CHAR_LPSM) {
1050 dev_dbg(hub_dev, "ganged power switching\n");
1053 dev_dbg(hub_dev, "individual port power switching\n");
1057 dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
1061 switch (wHubCharacteristics & HUB_CHAR_OCPM) {
1063 dev_dbg(hub_dev, "global over-current protection\n");
1066 dev_dbg(hub_dev, "individual port over-current protection\n");
1070 dev_dbg(hub_dev, "no over-current protection\n");
1074 spin_lock_init (&hub->tt.lock);
1075 INIT_LIST_HEAD (&hub->tt.clear_list);
1076 INIT_WORK(&hub->tt.clear_work, hub_tt_work);
1077 switch (hdev->descriptor.bDeviceProtocol) {
1081 dev_dbg(hub_dev, "Single TT\n");
1085 ret = usb_set_interface(hdev, 0, 1);
1087 dev_dbg(hub_dev, "TT per port\n");
1090 dev_err(hub_dev, "Using single TT (err %d)\n",
1095 /* USB 3.0 hubs don't have a TT */
1098 dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
1099 hdev->descriptor.bDeviceProtocol);
1103 /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
1104 switch (wHubCharacteristics & HUB_CHAR_TTTT) {
1105 case HUB_TTTT_8_BITS:
1106 if (hdev->descriptor.bDeviceProtocol != 0) {
1107 hub->tt.think_time = 666;
1108 dev_dbg(hub_dev, "TT requires at most %d "
1109 "FS bit times (%d ns)\n",
1110 8, hub->tt.think_time);
1113 case HUB_TTTT_16_BITS:
1114 hub->tt.think_time = 666 * 2;
1115 dev_dbg(hub_dev, "TT requires at most %d "
1116 "FS bit times (%d ns)\n",
1117 16, hub->tt.think_time);
1119 case HUB_TTTT_24_BITS:
1120 hub->tt.think_time = 666 * 3;
1121 dev_dbg(hub_dev, "TT requires at most %d "
1122 "FS bit times (%d ns)\n",
1123 24, hub->tt.think_time);
1125 case HUB_TTTT_32_BITS:
1126 hub->tt.think_time = 666 * 4;
1127 dev_dbg(hub_dev, "TT requires at most %d "
1128 "FS bit times (%d ns)\n",
1129 32, hub->tt.think_time);
1133 /* probe() zeroes hub->indicator[] */
1134 if (wHubCharacteristics & HUB_CHAR_PORTIND) {
1135 hub->has_indicators = 1;
1136 dev_dbg(hub_dev, "Port indicators are supported\n");
1139 dev_dbg(hub_dev, "power on to power good time: %dms\n",
1140 hub->descriptor->bPwrOn2PwrGood * 2);
1142 /* power budgeting mostly matters with bus-powered hubs,
1143 * and battery-powered root hubs (may provide just 8 mA).
1145 ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
1147 message = "can't get hub status";
1150 le16_to_cpus(&hubstatus);
1151 if (hdev == hdev->bus->root_hub) {
1152 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
1153 hub->mA_per_port = 500;
1155 hub->mA_per_port = hdev->bus_mA;
1156 hub->limited_power = 1;
1158 } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1159 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
1160 hub->descriptor->bHubContrCurrent);
1161 hub->limited_power = 1;
1162 if (hdev->maxchild > 0) {
1163 int remaining = hdev->bus_mA -
1164 hub->descriptor->bHubContrCurrent;
1166 if (remaining < hdev->maxchild * 100)
1168 "insufficient power available "
1169 "to use all downstream ports\n");
1170 hub->mA_per_port = 100; /* 7.2.1.1 */
1172 } else { /* Self-powered external hub */
1173 /* FIXME: What about battery-powered external hubs that
1174 * provide less current per port? */
1175 hub->mA_per_port = 500;
1177 if (hub->mA_per_port < 500)
1178 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
1181 /* Update the HCD's internal representation of this hub before khubd
1182 * starts getting port status changes for devices under the hub.
1184 hcd = bus_to_hcd(hdev->bus);
1185 if (hcd->driver->update_hub_device) {
1186 ret = hcd->driver->update_hub_device(hcd, hdev,
1187 &hub->tt, GFP_KERNEL);
1189 message = "can't update HCD hub info";
1194 ret = hub_hub_status(hub, &hubstatus, &hubchange);
1196 message = "can't get hub status";
1200 /* local power status reports aren't always correct */
1201 if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
1202 dev_dbg(hub_dev, "local power source is %s\n",
1203 (hubstatus & HUB_STATUS_LOCAL_POWER)
1204 ? "lost (inactive)" : "good");
1206 if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
1207 dev_dbg(hub_dev, "%sover-current condition exists\n",
1208 (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
1210 /* set up the interrupt endpoint
1211 * We use the EP's maxpacket size instead of (PORTS+1+7)/8
1212 * bytes as USB2.0[11.12.3] says because some hubs are known
1213 * to send more data (and thus cause overflow). For root hubs,
1214 * maxpktsize is defined in hcd.c's fake endpoint descriptors
1215 * to be big enough for at least USB_MAXCHILDREN ports. */
1216 pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
1217 maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
1219 if (maxp > sizeof(*hub->buffer))
1220 maxp = sizeof(*hub->buffer);
1222 hub->urb = usb_alloc_urb(0, GFP_KERNEL);
1228 usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1229 hub, endpoint->bInterval);
1231 /* maybe cycle the hub leds */
1232 if (hub->has_indicators && blinkenlights)
1233 hub->indicator [0] = INDICATOR_CYCLE;
1235 hub_activate(hub, HUB_INIT);
1239 dev_err (hub_dev, "config failed, %s (err %d)\n",
1241 /* hub_disconnect() frees urb and descriptor */
1245 static void hub_release(struct kref *kref)
1247 struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1249 usb_put_intf(to_usb_interface(hub->intfdev));
1253 static unsigned highspeed_hubs;
1255 static void hub_disconnect(struct usb_interface *intf)
1257 struct usb_hub *hub = usb_get_intfdata (intf);
1259 /* Take the hub off the event list and don't let it be added again */
1260 spin_lock_irq(&hub_event_lock);
1261 if (!list_empty(&hub->event_list)) {
1262 list_del_init(&hub->event_list);
1263 usb_autopm_put_interface_no_suspend(intf);
1265 hub->disconnected = 1;
1266 spin_unlock_irq(&hub_event_lock);
1268 /* Disconnect all children and quiesce the hub */
1270 hub_quiesce(hub, HUB_DISCONNECT);
1272 usb_set_intfdata (intf, NULL);
1273 hub->hdev->maxchild = 0;
1275 if (hub->hdev->speed == USB_SPEED_HIGH)
1278 usb_free_urb(hub->urb);
1279 kfree(hub->port_owners);
1280 kfree(hub->descriptor);
1284 kref_put(&hub->kref, hub_release);
1287 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1289 struct usb_host_interface *desc;
1290 struct usb_endpoint_descriptor *endpoint;
1291 struct usb_device *hdev;
1292 struct usb_hub *hub;
1294 desc = intf->cur_altsetting;
1295 hdev = interface_to_usbdev(intf);
1297 /* Hubs have proper suspend/resume support. USB 3.0 device suspend is
1298 * different from USB 2.0/1.1 device suspend, and unfortunately we
1299 * don't support it yet. So leave autosuspend disabled for USB 3.0
1300 * external hubs for now. Enable autosuspend for USB 3.0 roothubs,
1301 * since that isn't a "real" hub.
1303 if (!hub_is_superspeed(hdev) || !hdev->parent)
1304 usb_enable_autosuspend(hdev);
1306 if (hdev->level == MAX_TOPO_LEVEL) {
1308 "Unsupported bus topology: hub nested too deep\n");
1312 #ifdef CONFIG_USB_OTG_BLACKLIST_HUB
1314 dev_warn(&intf->dev, "ignoring external hub\n");
1319 /* Some hubs have a subclass of 1, which AFAICT according to the */
1320 /* specs is not defined, but it works */
1321 if ((desc->desc.bInterfaceSubClass != 0) &&
1322 (desc->desc.bInterfaceSubClass != 1)) {
1324 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
1328 /* Multiple endpoints? What kind of mutant ninja-hub is this? */
1329 if (desc->desc.bNumEndpoints != 1)
1330 goto descriptor_error;
1332 endpoint = &desc->endpoint[0].desc;
1334 /* If it's not an interrupt in endpoint, we'd better punt! */
1335 if (!usb_endpoint_is_int_in(endpoint))
1336 goto descriptor_error;
1338 /* We found a hub */
1339 dev_info (&intf->dev, "USB hub found\n");
1341 hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1343 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
1347 kref_init(&hub->kref);
1348 INIT_LIST_HEAD(&hub->event_list);
1349 hub->intfdev = &intf->dev;
1351 INIT_DELAYED_WORK(&hub->leds, led_work);
1352 INIT_DELAYED_WORK(&hub->init_work, NULL);
1355 usb_set_intfdata (intf, hub);
1356 intf->needs_remote_wakeup = 1;
1358 if (hdev->speed == USB_SPEED_HIGH)
1361 if (hub_configure(hub, endpoint) >= 0)
1364 hub_disconnect (intf);
1370 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1372 struct usb_device *hdev = interface_to_usbdev (intf);
1374 /* assert ifno == 0 (part of hub spec) */
1376 case USBDEVFS_HUB_PORTINFO: {
1377 struct usbdevfs_hub_portinfo *info = user_data;
1380 spin_lock_irq(&device_state_lock);
1381 if (hdev->devnum <= 0)
1384 info->nports = hdev->maxchild;
1385 for (i = 0; i < info->nports; i++) {
1386 if (hdev->children[i] == NULL)
1390 hdev->children[i]->devnum;
1393 spin_unlock_irq(&device_state_lock);
1395 return info->nports + 1;
1404 * Allow user programs to claim ports on a hub. When a device is attached
1405 * to one of these "claimed" ports, the program will "own" the device.
1407 static int find_port_owner(struct usb_device *hdev, unsigned port1,
1410 if (hdev->state == USB_STATE_NOTATTACHED)
1412 if (port1 == 0 || port1 > hdev->maxchild)
1415 /* This assumes that devices not managed by the hub driver
1416 * will always have maxchild equal to 0.
1418 *ppowner = &(hdev_to_hub(hdev)->port_owners[port1 - 1]);
1422 /* In the following three functions, the caller must hold hdev's lock */
1423 int usb_hub_claim_port(struct usb_device *hdev, unsigned port1, void *owner)
1428 rc = find_port_owner(hdev, port1, &powner);
1437 int usb_hub_release_port(struct usb_device *hdev, unsigned port1, void *owner)
1442 rc = find_port_owner(hdev, port1, &powner);
1445 if (*powner != owner)
1451 void usb_hub_release_all_ports(struct usb_device *hdev, void *owner)
1456 n = find_port_owner(hdev, 1, &powner);
1458 for (; n < hdev->maxchild; (++n, ++powner)) {
1459 if (*powner == owner)
1465 /* The caller must hold udev's lock */
1466 bool usb_device_is_owned(struct usb_device *udev)
1468 struct usb_hub *hub;
1470 if (udev->state == USB_STATE_NOTATTACHED || !udev->parent)
1472 hub = hdev_to_hub(udev->parent);
1473 return !!hub->port_owners[udev->portnum - 1];
1477 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1481 for (i = 0; i < udev->maxchild; ++i) {
1482 if (udev->children[i])
1483 recursively_mark_NOTATTACHED(udev->children[i]);
1485 if (udev->state == USB_STATE_SUSPENDED)
1486 udev->active_duration -= jiffies;
1487 udev->state = USB_STATE_NOTATTACHED;
1491 * usb_set_device_state - change a device's current state (usbcore, hcds)
1492 * @udev: pointer to device whose state should be changed
1493 * @new_state: new state value to be stored
1495 * udev->state is _not_ fully protected by the device lock. Although
1496 * most transitions are made only while holding the lock, the state can
1497 * can change to USB_STATE_NOTATTACHED at almost any time. This
1498 * is so that devices can be marked as disconnected as soon as possible,
1499 * without having to wait for any semaphores to be released. As a result,
1500 * all changes to any device's state must be protected by the
1501 * device_state_lock spinlock.
1503 * Once a device has been added to the device tree, all changes to its state
1504 * should be made using this routine. The state should _not_ be set directly.
1506 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1507 * Otherwise udev->state is set to new_state, and if new_state is
1508 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1509 * to USB_STATE_NOTATTACHED.
1511 void usb_set_device_state(struct usb_device *udev,
1512 enum usb_device_state new_state)
1514 unsigned long flags;
1517 spin_lock_irqsave(&device_state_lock, flags);
1518 if (udev->state == USB_STATE_NOTATTACHED)
1520 else if (new_state != USB_STATE_NOTATTACHED) {
1522 /* root hub wakeup capabilities are managed out-of-band
1523 * and may involve silicon errata ... ignore them here.
1526 if (udev->state == USB_STATE_SUSPENDED
1527 || new_state == USB_STATE_SUSPENDED)
1528 ; /* No change to wakeup settings */
1529 else if (new_state == USB_STATE_CONFIGURED)
1530 wakeup = udev->actconfig->desc.bmAttributes
1531 & USB_CONFIG_ATT_WAKEUP;
1535 if (udev->state == USB_STATE_SUSPENDED &&
1536 new_state != USB_STATE_SUSPENDED)
1537 udev->active_duration -= jiffies;
1538 else if (new_state == USB_STATE_SUSPENDED &&
1539 udev->state != USB_STATE_SUSPENDED)
1540 udev->active_duration += jiffies;
1541 udev->state = new_state;
1543 recursively_mark_NOTATTACHED(udev);
1544 spin_unlock_irqrestore(&device_state_lock, flags);
1546 device_set_wakeup_capable(&udev->dev, wakeup);
1548 EXPORT_SYMBOL_GPL(usb_set_device_state);
1551 * Choose a device number.
1553 * Device numbers are used as filenames in usbfs. On USB-1.1 and
1554 * USB-2.0 buses they are also used as device addresses, however on
1555 * USB-3.0 buses the address is assigned by the controller hardware
1556 * and it usually is not the same as the device number.
1558 * WUSB devices are simple: they have no hubs behind, so the mapping
1559 * device <-> virtual port number becomes 1:1. Why? to simplify the
1560 * life of the device connection logic in
1561 * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
1562 * handshake we need to assign a temporary address in the unauthorized
1563 * space. For simplicity we use the first virtual port number found to
1564 * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
1565 * and that becomes it's address [X < 128] or its unauthorized address
1568 * We add 1 as an offset to the one-based USB-stack port number
1569 * (zero-based wusb virtual port index) for two reasons: (a) dev addr
1570 * 0 is reserved by USB for default address; (b) Linux's USB stack
1571 * uses always #1 for the root hub of the controller. So USB stack's
1572 * port #1, which is wusb virtual-port #0 has address #2.
1574 * Devices connected under xHCI are not as simple. The host controller
1575 * supports virtualization, so the hardware assigns device addresses and
1576 * the HCD must setup data structures before issuing a set address
1577 * command to the hardware.
1579 static void choose_devnum(struct usb_device *udev)
1582 struct usb_bus *bus = udev->bus;
1584 /* If khubd ever becomes multithreaded, this will need a lock */
1586 devnum = udev->portnum + 1;
1587 BUG_ON(test_bit(devnum, bus->devmap.devicemap));
1589 /* Try to allocate the next devnum beginning at
1590 * bus->devnum_next. */
1591 devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1594 devnum = find_next_zero_bit(bus->devmap.devicemap,
1596 bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1599 set_bit(devnum, bus->devmap.devicemap);
1600 udev->devnum = devnum;
1604 static void release_devnum(struct usb_device *udev)
1606 if (udev->devnum > 0) {
1607 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1612 static void update_devnum(struct usb_device *udev, int devnum)
1614 /* The address for a WUSB device is managed by wusbcore. */
1616 udev->devnum = devnum;
1619 static void hub_free_dev(struct usb_device *udev)
1621 struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1623 /* Root hubs aren't real devices, so don't free HCD resources */
1624 if (hcd->driver->free_dev && udev->parent)
1625 hcd->driver->free_dev(hcd, udev);
1629 * usb_disconnect - disconnect a device (usbcore-internal)
1630 * @pdev: pointer to device being disconnected
1631 * Context: !in_interrupt ()
1633 * Something got disconnected. Get rid of it and all of its children.
1635 * If *pdev is a normal device then the parent hub must already be locked.
1636 * If *pdev is a root hub then this routine will acquire the
1637 * usb_bus_list_lock on behalf of the caller.
1639 * Only hub drivers (including virtual root hub drivers for host
1640 * controllers) should ever call this.
1642 * This call is synchronous, and may not be used in an interrupt context.
1644 void usb_disconnect(struct usb_device **pdev)
1646 struct usb_device *udev = *pdev;
1649 /* mark the device as inactive, so any further urb submissions for
1650 * this device (and any of its children) will fail immediately.
1651 * this quiesces everything except pending urbs.
1653 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1654 dev_info(&udev->dev, "USB disconnect, device number %d\n",
1657 usb_lock_device(udev);
1659 /* Free up all the children before we remove this device */
1660 for (i = 0; i < USB_MAXCHILDREN; i++) {
1661 if (udev->children[i])
1662 usb_disconnect(&udev->children[i]);
1665 /* deallocate hcd/hardware state ... nuking all pending urbs and
1666 * cleaning up all state associated with the current configuration
1667 * so that the hardware is now fully quiesced.
1669 dev_dbg (&udev->dev, "unregistering device\n");
1670 usb_disable_device(udev, 0);
1671 usb_hcd_synchronize_unlinks(udev);
1673 usb_remove_ep_devs(&udev->ep0);
1674 usb_unlock_device(udev);
1676 /* Unregister the device. The device driver is responsible
1677 * for de-configuring the device and invoking the remove-device
1678 * notifier chain (used by usbfs and possibly others).
1680 device_del(&udev->dev);
1682 /* Free the device number and delete the parent's children[]
1683 * (or root_hub) pointer.
1685 release_devnum(udev);
1687 /* Avoid races with recursively_mark_NOTATTACHED() */
1688 spin_lock_irq(&device_state_lock);
1690 spin_unlock_irq(&device_state_lock);
1694 put_device(&udev->dev);
1697 #ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
1698 static void show_string(struct usb_device *udev, char *id, char *string)
1702 dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1705 static void announce_device(struct usb_device *udev)
1707 dev_info(&udev->dev, "New USB device found, idVendor=%04x, idProduct=%04x\n",
1708 le16_to_cpu(udev->descriptor.idVendor),
1709 le16_to_cpu(udev->descriptor.idProduct));
1710 dev_info(&udev->dev,
1711 "New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
1712 udev->descriptor.iManufacturer,
1713 udev->descriptor.iProduct,
1714 udev->descriptor.iSerialNumber);
1715 show_string(udev, "Product", udev->product);
1716 show_string(udev, "Manufacturer", udev->manufacturer);
1717 show_string(udev, "SerialNumber", udev->serial);
1720 static inline void announce_device(struct usb_device *udev) { }
1723 #ifdef CONFIG_USB_OTG
1724 #include "otg_whitelist.h"
1728 * usb_enumerate_device_otg - FIXME (usbcore-internal)
1729 * @udev: newly addressed device (in ADDRESS state)
1731 * Finish enumeration for On-The-Go devices
1733 static int usb_enumerate_device_otg(struct usb_device *udev)
1737 #ifdef CONFIG_USB_OTG
1739 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1740 * to wake us after we've powered off VBUS; and HNP, switching roles
1741 * "host" to "peripheral". The OTG descriptor helps figure this out.
1743 if (!udev->bus->is_b_host
1745 && udev->parent == udev->bus->root_hub) {
1746 struct usb_otg_descriptor *desc = NULL;
1747 struct usb_bus *bus = udev->bus;
1749 /* descriptor may appear anywhere in config */
1750 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1751 le16_to_cpu(udev->config[0].desc.wTotalLength),
1752 USB_DT_OTG, (void **) &desc) == 0) {
1753 if (desc->bmAttributes & USB_OTG_HNP) {
1754 unsigned port1 = udev->portnum;
1756 dev_info(&udev->dev,
1757 "Dual-Role OTG device on %sHNP port\n",
1758 (port1 == bus->otg_port)
1761 /* enable HNP before suspend, it's simpler */
1762 if (port1 == bus->otg_port)
1763 bus->b_hnp_enable = 1;
1764 err = usb_control_msg(udev,
1765 usb_sndctrlpipe(udev, 0),
1766 USB_REQ_SET_FEATURE, 0,
1768 ? USB_DEVICE_B_HNP_ENABLE
1769 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1770 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1772 /* OTG MESSAGE: report errors here,
1773 * customize to match your product.
1775 dev_info(&udev->dev,
1776 "can't set HNP mode: %d\n",
1778 bus->b_hnp_enable = 0;
1784 if (!is_targeted(udev)) {
1786 /* Maybe it can talk to us, though we can't talk to it.
1787 * (Includes HNP test device.)
1789 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1790 err = usb_port_suspend(udev, PMSG_SUSPEND);
1792 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1804 * usb_enumerate_device - Read device configs/intfs/otg (usbcore-internal)
1805 * @udev: newly addressed device (in ADDRESS state)
1807 * This is only called by usb_new_device() and usb_authorize_device()
1808 * and FIXME -- all comments that apply to them apply here wrt to
1811 * If the device is WUSB and not authorized, we don't attempt to read
1812 * the string descriptors, as they will be errored out by the device
1813 * until it has been authorized.
1815 static int usb_enumerate_device(struct usb_device *udev)
1819 if (udev->config == NULL) {
1820 err = usb_get_configuration(udev);
1822 dev_err(&udev->dev, "can't read configurations, error %d\n",
1827 if (udev->wusb == 1 && udev->authorized == 0) {
1828 udev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1829 udev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1830 udev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1833 /* read the standard strings and cache them if present */
1834 udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1835 udev->manufacturer = usb_cache_string(udev,
1836 udev->descriptor.iManufacturer);
1837 udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1839 err = usb_enumerate_device_otg(udev);
1846 * usb_new_device - perform initial device setup (usbcore-internal)
1847 * @udev: newly addressed device (in ADDRESS state)
1849 * This is called with devices which have been detected but not fully
1850 * enumerated. The device descriptor is available, but not descriptors
1851 * for any device configuration. The caller must have locked either
1852 * the parent hub (if udev is a normal device) or else the
1853 * usb_bus_list_lock (if udev is a root hub). The parent's pointer to
1854 * udev has already been installed, but udev is not yet visible through
1855 * sysfs or other filesystem code.
1857 * It will return if the device is configured properly or not. Zero if
1858 * the interface was registered with the driver core; else a negative
1861 * This call is synchronous, and may not be used in an interrupt context.
1863 * Only the hub driver or root-hub registrar should ever call this.
1865 int usb_new_device(struct usb_device *udev)
1870 /* Initialize non-root-hub device wakeup to disabled;
1871 * device (un)configuration controls wakeup capable
1872 * sysfs power/wakeup controls wakeup enabled/disabled
1874 device_init_wakeup(&udev->dev, 0);
1877 /* Tell the runtime-PM framework the device is active */
1878 pm_runtime_set_active(&udev->dev);
1879 pm_runtime_get_noresume(&udev->dev);
1880 pm_runtime_use_autosuspend(&udev->dev);
1881 pm_runtime_enable(&udev->dev);
1883 /* By default, forbid autosuspend for all devices. It will be
1884 * allowed for hubs during binding.
1886 usb_disable_autosuspend(udev);
1888 err = usb_enumerate_device(udev); /* Read descriptors */
1891 dev_dbg(&udev->dev, "udev %d, busnum %d, minor = %d\n",
1892 udev->devnum, udev->bus->busnum,
1893 (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
1894 /* export the usbdev device-node for libusb */
1895 udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
1896 (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
1898 /* Tell the world! */
1899 announce_device(udev);
1902 add_device_randomness(udev->serial, strlen(udev->serial));
1904 add_device_randomness(udev->product, strlen(udev->product));
1905 if (udev->manufacturer)
1906 add_device_randomness(udev->manufacturer,
1907 strlen(udev->manufacturer));
1909 device_enable_async_suspend(&udev->dev);
1910 /* Register the device. The device driver is responsible
1911 * for configuring the device and invoking the add-device
1912 * notifier chain (used by usbfs and possibly others).
1914 err = device_add(&udev->dev);
1916 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1920 (void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev);
1921 usb_mark_last_busy(udev);
1922 pm_runtime_put_sync_autosuspend(&udev->dev);
1926 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1927 pm_runtime_disable(&udev->dev);
1928 pm_runtime_set_suspended(&udev->dev);
1934 * usb_deauthorize_device - deauthorize a device (usbcore-internal)
1935 * @usb_dev: USB device
1937 * Move the USB device to a very basic state where interfaces are disabled
1938 * and the device is in fact unconfigured and unusable.
1940 * We share a lock (that we have) with device_del(), so we need to
1943 int usb_deauthorize_device(struct usb_device *usb_dev)
1945 usb_lock_device(usb_dev);
1946 if (usb_dev->authorized == 0)
1947 goto out_unauthorized;
1949 usb_dev->authorized = 0;
1950 usb_set_configuration(usb_dev, -1);
1952 kfree(usb_dev->product);
1953 usb_dev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1954 kfree(usb_dev->manufacturer);
1955 usb_dev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1956 kfree(usb_dev->serial);
1957 usb_dev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1959 usb_destroy_configuration(usb_dev);
1960 usb_dev->descriptor.bNumConfigurations = 0;
1963 usb_unlock_device(usb_dev);
1968 int usb_authorize_device(struct usb_device *usb_dev)
1972 usb_lock_device(usb_dev);
1973 if (usb_dev->authorized == 1)
1974 goto out_authorized;
1976 result = usb_autoresume_device(usb_dev);
1978 dev_err(&usb_dev->dev,
1979 "can't autoresume for authorization: %d\n", result);
1980 goto error_autoresume;
1982 result = usb_get_device_descriptor(usb_dev, sizeof(usb_dev->descriptor));
1984 dev_err(&usb_dev->dev, "can't re-read device descriptor for "
1985 "authorization: %d\n", result);
1986 goto error_device_descriptor;
1989 kfree(usb_dev->product);
1990 usb_dev->product = NULL;
1991 kfree(usb_dev->manufacturer);
1992 usb_dev->manufacturer = NULL;
1993 kfree(usb_dev->serial);
1994 usb_dev->serial = NULL;
1996 usb_dev->authorized = 1;
1997 result = usb_enumerate_device(usb_dev);
1999 goto error_enumerate;
2000 /* Choose and set the configuration. This registers the interfaces
2001 * with the driver core and lets interface drivers bind to them.
2003 c = usb_choose_configuration(usb_dev);
2005 result = usb_set_configuration(usb_dev, c);
2007 dev_err(&usb_dev->dev,
2008 "can't set config #%d, error %d\n", c, result);
2009 /* This need not be fatal. The user can try to
2010 * set other configurations. */
2013 dev_info(&usb_dev->dev, "authorized to connect\n");
2016 error_device_descriptor:
2017 usb_autosuspend_device(usb_dev);
2020 usb_unlock_device(usb_dev); // complements locktree
2025 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
2026 static unsigned hub_is_wusb(struct usb_hub *hub)
2028 struct usb_hcd *hcd;
2029 if (hub->hdev->parent != NULL) /* not a root hub? */
2031 hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
2032 return hcd->wireless;
2036 #define PORT_RESET_TRIES 5
2037 #define SET_ADDRESS_TRIES 2
2038 #define GET_DESCRIPTOR_TRIES 2
2039 #define SET_CONFIG_TRIES (2 * (use_both_schemes + 1))
2040 #define USE_NEW_SCHEME(i) ((i) / 2 == old_scheme_first)
2042 #define HUB_ROOT_RESET_TIME 50 /* times are in msec */
2043 #define HUB_SHORT_RESET_TIME 10
2044 #define HUB_BH_RESET_TIME 50
2045 #define HUB_LONG_RESET_TIME 200
2046 #define HUB_RESET_TIMEOUT 500
2048 static int hub_port_reset(struct usb_hub *hub, int port1,
2049 struct usb_device *udev, unsigned int delay, bool warm);
2051 /* Is a USB 3.0 port in the Inactive or Complinance Mode state?
2052 * Port worm reset is required to recover
2054 static bool hub_port_warm_reset_required(struct usb_hub *hub, u16 portstatus)
2056 return hub_is_superspeed(hub->hdev) &&
2057 (((portstatus & USB_PORT_STAT_LINK_STATE) ==
2058 USB_SS_PORT_LS_SS_INACTIVE) ||
2059 ((portstatus & USB_PORT_STAT_LINK_STATE) ==
2060 USB_SS_PORT_LS_COMP_MOD)) ;
2063 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
2064 struct usb_device *udev, unsigned int delay, bool warm)
2066 int delay_time, ret;
2070 for (delay_time = 0;
2071 delay_time < HUB_RESET_TIMEOUT;
2072 delay_time += delay) {
2073 /* wait to give the device a chance to reset */
2076 /* read and decode port status */
2077 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2082 * Some buggy devices require a warm reset to be issued even
2083 * when the port appears not to be connected.
2087 * Some buggy devices can cause an NEC host controller
2088 * to transition to the "Error" state after a hot port
2089 * reset. This will show up as the port state in
2090 * "Inactive", and the port may also report a
2091 * disconnect. Forcing a warm port reset seems to make
2094 * See https://bugzilla.kernel.org/show_bug.cgi?id=41752
2096 if (hub_port_warm_reset_required(hub, portstatus)) {
2099 if ((portchange & USB_PORT_STAT_C_CONNECTION))
2100 clear_port_feature(hub->hdev, port1,
2101 USB_PORT_FEAT_C_CONNECTION);
2102 if (portchange & USB_PORT_STAT_C_LINK_STATE)
2103 clear_port_feature(hub->hdev, port1,
2104 USB_PORT_FEAT_C_PORT_LINK_STATE);
2105 if (portchange & USB_PORT_STAT_C_RESET)
2106 clear_port_feature(hub->hdev, port1,
2107 USB_PORT_FEAT_C_RESET);
2108 dev_dbg(hub->intfdev, "hot reset failed, warm reset port %d\n",
2110 ret = hub_port_reset(hub, port1,
2111 udev, HUB_BH_RESET_TIME,
2113 if ((portchange & USB_PORT_STAT_C_CONNECTION))
2114 clear_port_feature(hub->hdev, port1,
2115 USB_PORT_FEAT_C_CONNECTION);
2118 /* Device went away? */
2119 if (!(portstatus & USB_PORT_STAT_CONNECTION))
2122 /* bomb out completely if the connection bounced */
2123 if ((portchange & USB_PORT_STAT_C_CONNECTION))
2126 /* if we`ve finished resetting, then break out of
2129 if (!(portstatus & USB_PORT_STAT_RESET) &&
2130 (portstatus & USB_PORT_STAT_ENABLE)) {
2131 if (hub_is_wusb(hub))
2132 udev->speed = USB_SPEED_WIRELESS;
2133 else if (hub_is_superspeed(hub->hdev))
2134 udev->speed = USB_SPEED_SUPER;
2135 else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
2136 udev->speed = USB_SPEED_HIGH;
2137 else if (portstatus & USB_PORT_STAT_LOW_SPEED)
2138 udev->speed = USB_SPEED_LOW;
2140 udev->speed = USB_SPEED_FULL;
2144 if (portchange & USB_PORT_STAT_C_BH_RESET)
2148 /* switch to the long delay after two short delay failures */
2149 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
2150 delay = HUB_LONG_RESET_TIME;
2152 dev_dbg (hub->intfdev,
2153 "port %d not %sreset yet, waiting %dms\n",
2154 port1, warm ? "warm " : "", delay);
2160 static void hub_port_finish_reset(struct usb_hub *hub, int port1,
2161 struct usb_device *udev, int *status, bool warm)
2166 struct usb_hcd *hcd;
2167 /* TRSTRCY = 10 ms; plus some extra */
2169 update_devnum(udev, 0);
2170 hcd = bus_to_hcd(udev->bus);
2171 if (hcd->driver->reset_device) {
2172 *status = hcd->driver->reset_device(hcd, udev);
2174 dev_err(&udev->dev, "Cannot reset "
2175 "HCD device state\n");
2183 clear_port_feature(hub->hdev,
2184 port1, USB_PORT_FEAT_C_RESET);
2185 /* FIXME need disconnect() for NOTATTACHED device */
2187 clear_port_feature(hub->hdev, port1,
2188 USB_PORT_FEAT_C_BH_PORT_RESET);
2189 clear_port_feature(hub->hdev, port1,
2190 USB_PORT_FEAT_C_PORT_LINK_STATE);
2192 usb_set_device_state(udev, *status
2193 ? USB_STATE_NOTATTACHED
2194 : USB_STATE_DEFAULT);
2200 /* Handle port reset and port warm(BH) reset (for USB3 protocol ports) */
2201 static int hub_port_reset(struct usb_hub *hub, int port1,
2202 struct usb_device *udev, unsigned int delay, bool warm)
2207 /* Block EHCI CF initialization during the port reset.
2208 * Some companion controllers don't like it when they mix.
2210 down_read(&ehci_cf_port_reset_rwsem);
2212 if (!hub_is_superspeed(hub->hdev)) {
2213 dev_err(hub->intfdev, "only USB3 hub support "
2219 /* Reset the port */
2220 for (i = 0; i < PORT_RESET_TRIES; i++) {
2221 status = set_port_feature(hub->hdev, port1, (warm ?
2222 USB_PORT_FEAT_BH_PORT_RESET :
2223 USB_PORT_FEAT_RESET));
2225 dev_err(hub->intfdev,
2226 "cannot %sreset port %d (err = %d)\n",
2227 warm ? "warm " : "", port1, status);
2229 status = hub_port_wait_reset(hub, port1, udev, delay,
2231 if (status && status != -ENOTCONN)
2232 dev_dbg(hub->intfdev,
2233 "port_wait_reset: err = %d\n",
2237 /* return on disconnect or reset */
2238 if (status == 0 || status == -ENOTCONN || status == -ENODEV) {
2239 hub_port_finish_reset(hub, port1, udev, &status, warm);
2243 dev_dbg (hub->intfdev,
2244 "port %d not enabled, trying %sreset again...\n",
2245 port1, warm ? "warm " : "");
2246 delay = HUB_LONG_RESET_TIME;
2249 dev_err (hub->intfdev,
2250 "Cannot enable port %i. Maybe the USB cable is bad?\n",
2255 up_read(&ehci_cf_port_reset_rwsem);
2260 /* Check if a port is power on */
2261 static int port_is_power_on(struct usb_hub *hub, unsigned portstatus)
2265 if (hub_is_superspeed(hub->hdev)) {
2266 if (portstatus & USB_SS_PORT_STAT_POWER)
2269 if (portstatus & USB_PORT_STAT_POWER)
2278 /* Check if a port is suspended(USB2.0 port) or in U3 state(USB3.0 port) */
2279 static int port_is_suspended(struct usb_hub *hub, unsigned portstatus)
2283 if (hub_is_superspeed(hub->hdev)) {
2284 if ((portstatus & USB_PORT_STAT_LINK_STATE)
2285 == USB_SS_PORT_LS_U3)
2288 if (portstatus & USB_PORT_STAT_SUSPEND)
2295 /* Determine whether the device on a port is ready for a normal resume,
2296 * is ready for a reset-resume, or should be disconnected.
2298 static int check_port_resume_type(struct usb_device *udev,
2299 struct usb_hub *hub, int port1,
2300 int status, unsigned portchange, unsigned portstatus)
2302 /* Is the device still present? */
2303 if (status || port_is_suspended(hub, portstatus) ||
2304 !port_is_power_on(hub, portstatus) ||
2305 !(portstatus & USB_PORT_STAT_CONNECTION)) {
2310 /* Can't do a normal resume if the port isn't enabled,
2311 * so try a reset-resume instead.
2313 else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
2314 if (udev->persist_enabled)
2315 udev->reset_resume = 1;
2321 dev_dbg(hub->intfdev,
2322 "port %d status %04x.%04x after resume, %d\n",
2323 port1, portchange, portstatus, status);
2324 } else if (udev->reset_resume) {
2326 /* Late port handoff can set status-change bits */
2327 if (portchange & USB_PORT_STAT_C_CONNECTION)
2328 clear_port_feature(hub->hdev, port1,
2329 USB_PORT_FEAT_C_CONNECTION);
2330 if (portchange & USB_PORT_STAT_C_ENABLE)
2331 clear_port_feature(hub->hdev, port1,
2332 USB_PORT_FEAT_C_ENABLE);
2338 #ifdef CONFIG_USB_SUSPEND
2341 * usb_port_suspend - suspend a usb device's upstream port
2342 * @udev: device that's no longer in active use, not a root hub
2343 * Context: must be able to sleep; device not locked; pm locks held
2345 * Suspends a USB device that isn't in active use, conserving power.
2346 * Devices may wake out of a suspend, if anything important happens,
2347 * using the remote wakeup mechanism. They may also be taken out of
2348 * suspend by the host, using usb_port_resume(). It's also routine
2349 * to disconnect devices while they are suspended.
2351 * This only affects the USB hardware for a device; its interfaces
2352 * (and, for hubs, child devices) must already have been suspended.
2354 * Selective port suspend reduces power; most suspended devices draw
2355 * less than 500 uA. It's also used in OTG, along with remote wakeup.
2356 * All devices below the suspended port are also suspended.
2358 * Devices leave suspend state when the host wakes them up. Some devices
2359 * also support "remote wakeup", where the device can activate the USB
2360 * tree above them to deliver data, such as a keypress or packet. In
2361 * some cases, this wakes the USB host.
2363 * Suspending OTG devices may trigger HNP, if that's been enabled
2364 * between a pair of dual-role devices. That will change roles, such
2365 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
2367 * Devices on USB hub ports have only one "suspend" state, corresponding
2368 * to ACPI D2, "may cause the device to lose some context".
2369 * State transitions include:
2371 * - suspend, resume ... when the VBUS power link stays live
2372 * - suspend, disconnect ... VBUS lost
2374 * Once VBUS drop breaks the circuit, the port it's using has to go through
2375 * normal re-enumeration procedures, starting with enabling VBUS power.
2376 * Other than re-initializing the hub (plug/unplug, except for root hubs),
2377 * Linux (2.6) currently has NO mechanisms to initiate that: no khubd
2378 * timer, no SRP, no requests through sysfs.
2380 * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
2381 * the root hub for their bus goes into global suspend ... so we don't
2382 * (falsely) update the device power state to say it suspended.
2384 * Returns 0 on success, else negative errno.
2386 int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
2388 struct usb_hub *hub = hdev_to_hub(udev->parent);
2389 int port1 = udev->portnum;
2392 /* enable remote wakeup when appropriate; this lets the device
2393 * wake up the upstream hub (including maybe the root hub).
2395 * NOTE: OTG devices may issue remote wakeup (or SRP) even when
2396 * we don't explicitly enable it here.
2398 if (udev->do_remote_wakeup) {
2399 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2400 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
2401 USB_DEVICE_REMOTE_WAKEUP, 0,
2403 USB_CTRL_SET_TIMEOUT);
2405 dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
2407 /* bail if autosuspend is requested */
2408 if (PMSG_IS_AUTO(msg))
2413 /* disable USB2 hardware LPM */
2414 if (udev->usb2_hw_lpm_enabled == 1)
2415 usb_set_usb2_hardware_lpm(udev, 0);
2418 if (hub_is_superspeed(hub->hdev))
2419 status = set_port_feature(hub->hdev,
2420 port1 | (USB_SS_PORT_LS_U3 << 3),
2421 USB_PORT_FEAT_LINK_STATE);
2423 status = set_port_feature(hub->hdev, port1,
2424 USB_PORT_FEAT_SUSPEND);
2426 dev_dbg(hub->intfdev, "can't suspend port %d, status %d\n",
2428 /* paranoia: "should not happen" */
2429 if (udev->do_remote_wakeup)
2430 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2431 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
2432 USB_DEVICE_REMOTE_WAKEUP, 0,
2434 USB_CTRL_SET_TIMEOUT);
2436 /* Try to enable USB2 hardware LPM again */
2437 if (udev->usb2_hw_lpm_capable == 1)
2438 usb_set_usb2_hardware_lpm(udev, 1);
2440 /* System sleep transitions should never fail */
2441 if (!PMSG_IS_AUTO(msg))
2444 /* device has up to 10 msec to fully suspend */
2445 dev_dbg(&udev->dev, "usb %ssuspend, wakeup %d\n",
2446 (PMSG_IS_AUTO(msg) ? "auto-" : ""),
2447 udev->do_remote_wakeup);
2448 usb_set_device_state(udev, USB_STATE_SUSPENDED);
2451 usb_mark_last_busy(hub->hdev);
2456 * If the USB "suspend" state is in use (rather than "global suspend"),
2457 * many devices will be individually taken out of suspend state using
2458 * special "resume" signaling. This routine kicks in shortly after
2459 * hardware resume signaling is finished, either because of selective
2460 * resume (by host) or remote wakeup (by device) ... now see what changed
2461 * in the tree that's rooted at this device.
2463 * If @udev->reset_resume is set then the device is reset before the
2464 * status check is done.
2466 static int finish_port_resume(struct usb_device *udev)
2471 /* caller owns the udev device lock */
2472 dev_dbg(&udev->dev, "%s\n",
2473 udev->reset_resume ? "finish reset-resume" : "finish resume");
2475 /* usb ch9 identifies four variants of SUSPENDED, based on what
2476 * state the device resumes to. Linux currently won't see the
2477 * first two on the host side; they'd be inside hub_port_init()
2478 * during many timeouts, but khubd can't suspend until later.
2480 usb_set_device_state(udev, udev->actconfig
2481 ? USB_STATE_CONFIGURED
2482 : USB_STATE_ADDRESS);
2484 /* 10.5.4.5 says not to reset a suspended port if the attached
2485 * device is enabled for remote wakeup. Hence the reset
2486 * operation is carried out here, after the port has been
2489 if (udev->reset_resume)
2491 status = usb_reset_and_verify_device(udev);
2493 /* 10.5.4.5 says be sure devices in the tree are still there.
2494 * For now let's assume the device didn't go crazy on resume,
2495 * and device drivers will know about any resume quirks.
2499 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
2501 status = (status > 0 ? 0 : -ENODEV);
2503 /* If a normal resume failed, try doing a reset-resume */
2504 if (status && !udev->reset_resume && udev->persist_enabled) {
2505 dev_dbg(&udev->dev, "retry with reset-resume\n");
2506 udev->reset_resume = 1;
2507 goto retry_reset_resume;
2512 dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
2514 } else if (udev->actconfig) {
2515 le16_to_cpus(&devstatus);
2516 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
2517 status = usb_control_msg(udev,
2518 usb_sndctrlpipe(udev, 0),
2519 USB_REQ_CLEAR_FEATURE,
2521 USB_DEVICE_REMOTE_WAKEUP, 0,
2523 USB_CTRL_SET_TIMEOUT);
2526 "disable remote wakeup, status %d\n",
2535 * usb_port_resume - re-activate a suspended usb device's upstream port
2536 * @udev: device to re-activate, not a root hub
2537 * Context: must be able to sleep; device not locked; pm locks held
2539 * This will re-activate the suspended device, increasing power usage
2540 * while letting drivers communicate again with its endpoints.
2541 * USB resume explicitly guarantees that the power session between
2542 * the host and the device is the same as it was when the device
2545 * If @udev->reset_resume is set then this routine won't check that the
2546 * port is still enabled. Furthermore, finish_port_resume() above will
2547 * reset @udev. The end result is that a broken power session can be
2548 * recovered and @udev will appear to persist across a loss of VBUS power.
2550 * For example, if a host controller doesn't maintain VBUS suspend current
2551 * during a system sleep or is reset when the system wakes up, all the USB
2552 * power sessions below it will be broken. This is especially troublesome
2553 * for mass-storage devices containing mounted filesystems, since the
2554 * device will appear to have disconnected and all the memory mappings
2555 * to it will be lost. Using the USB_PERSIST facility, the device can be
2556 * made to appear as if it had not disconnected.
2558 * This facility can be dangerous. Although usb_reset_and_verify_device() makes
2559 * every effort to insure that the same device is present after the
2560 * reset as before, it cannot provide a 100% guarantee. Furthermore it's
2561 * quite possible for a device to remain unaltered but its media to be
2562 * changed. If the user replaces a flash memory card while the system is
2563 * asleep, he will have only himself to blame when the filesystem on the
2564 * new card is corrupted and the system crashes.
2566 * Returns 0 on success, else negative errno.
2568 int usb_port_resume(struct usb_device *udev, pm_message_t msg)
2570 struct usb_hub *hub = hdev_to_hub(udev->parent);
2571 int port1 = udev->portnum;
2573 u16 portchange, portstatus;
2575 /* Skip the initial Clear-Suspend step for a remote wakeup */
2576 status = hub_port_status(hub, port1, &portstatus, &portchange);
2577 if (status == 0 && !port_is_suspended(hub, portstatus))
2578 goto SuspendCleared;
2580 // dev_dbg(hub->intfdev, "resume port %d\n", port1);
2582 set_bit(port1, hub->busy_bits);
2584 /* see 7.1.7.7; affects power usage, but not budgeting */
2585 if (hub_is_superspeed(hub->hdev))
2586 status = set_port_feature(hub->hdev,
2587 port1 | (USB_SS_PORT_LS_U0 << 3),
2588 USB_PORT_FEAT_LINK_STATE);
2590 status = clear_port_feature(hub->hdev,
2591 port1, USB_PORT_FEAT_SUSPEND);
2593 dev_dbg(hub->intfdev, "can't resume port %d, status %d\n",
2596 /* drive resume for at least 20 msec */
2597 dev_dbg(&udev->dev, "usb %sresume\n",
2598 (PMSG_IS_AUTO(msg) ? "auto-" : ""));
2601 /* Virtual root hubs can trigger on GET_PORT_STATUS to
2602 * stop resume signaling. Then finish the resume
2605 status = hub_port_status(hub, port1, &portstatus, &portchange);
2607 /* TRSMRCY = 10 msec */
2613 if (hub_is_superspeed(hub->hdev)) {
2614 if (portchange & USB_PORT_STAT_C_LINK_STATE)
2615 clear_port_feature(hub->hdev, port1,
2616 USB_PORT_FEAT_C_PORT_LINK_STATE);
2618 if (portchange & USB_PORT_STAT_C_SUSPEND)
2619 clear_port_feature(hub->hdev, port1,
2620 USB_PORT_FEAT_C_SUSPEND);
2624 clear_bit(port1, hub->busy_bits);
2626 status = check_port_resume_type(udev,
2627 hub, port1, status, portchange, portstatus);
2629 status = finish_port_resume(udev);
2631 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2632 hub_port_logical_disconnect(hub, port1);
2634 /* Try to enable USB2 hardware LPM */
2635 if (udev->usb2_hw_lpm_capable == 1)
2636 usb_set_usb2_hardware_lpm(udev, 1);
2642 /* caller has locked udev */
2643 int usb_remote_wakeup(struct usb_device *udev)
2647 if (udev->state == USB_STATE_SUSPENDED) {
2648 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
2649 status = usb_autoresume_device(udev);
2651 /* Let the drivers do their thing, then... */
2652 usb_autosuspend_device(udev);
2658 #else /* CONFIG_USB_SUSPEND */
2660 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
2662 int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
2667 /* However we may need to do a reset-resume */
2669 int usb_port_resume(struct usb_device *udev, pm_message_t msg)
2671 struct usb_hub *hub = hdev_to_hub(udev->parent);
2672 int port1 = udev->portnum;
2674 u16 portchange, portstatus;
2676 status = hub_port_status(hub, port1, &portstatus, &portchange);
2677 status = check_port_resume_type(udev,
2678 hub, port1, status, portchange, portstatus);
2681 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2682 hub_port_logical_disconnect(hub, port1);
2683 } else if (udev->reset_resume) {
2684 dev_dbg(&udev->dev, "reset-resume\n");
2685 status = usb_reset_and_verify_device(udev);
2692 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
2694 struct usb_hub *hub = usb_get_intfdata (intf);
2695 struct usb_device *hdev = hub->hdev;
2698 /* Warn if children aren't already suspended */
2699 for (port1 = 1; port1 <= hdev->maxchild; port1++) {
2700 struct usb_device *udev;
2702 udev = hdev->children [port1-1];
2703 if (udev && udev->can_submit) {
2704 dev_warn(&intf->dev, "port %d nyet suspended\n", port1);
2705 if (PMSG_IS_AUTO(msg))
2710 dev_dbg(&intf->dev, "%s\n", __func__);
2712 /* stop khubd and related activity */
2713 hub_quiesce(hub, HUB_SUSPEND);
2717 static int hub_resume(struct usb_interface *intf)
2719 struct usb_hub *hub = usb_get_intfdata(intf);
2721 dev_dbg(&intf->dev, "%s\n", __func__);
2722 hub_activate(hub, HUB_RESUME);
2726 static int hub_reset_resume(struct usb_interface *intf)
2728 struct usb_hub *hub = usb_get_intfdata(intf);
2730 dev_dbg(&intf->dev, "%s\n", __func__);
2731 hub_activate(hub, HUB_RESET_RESUME);
2736 * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
2737 * @rhdev: struct usb_device for the root hub
2739 * The USB host controller driver calls this function when its root hub
2740 * is resumed and Vbus power has been interrupted or the controller
2741 * has been reset. The routine marks @rhdev as having lost power.
2742 * When the hub driver is resumed it will take notice and carry out
2743 * power-session recovery for all the "USB-PERSIST"-enabled child devices;
2744 * the others will be disconnected.
2746 void usb_root_hub_lost_power(struct usb_device *rhdev)
2748 dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
2749 rhdev->reset_resume = 1;
2751 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
2753 #else /* CONFIG_PM */
2755 #define hub_suspend NULL
2756 #define hub_resume NULL
2757 #define hub_reset_resume NULL
2761 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2763 * Between connect detection and reset signaling there must be a delay
2764 * of 100ms at least for debounce and power-settling. The corresponding
2765 * timer shall restart whenever the downstream port detects a disconnect.
2767 * Apparently there are some bluetooth and irda-dongles and a number of
2768 * low-speed devices for which this debounce period may last over a second.
2769 * Not covered by the spec - but easy to deal with.
2771 * This implementation uses a 1500ms total debounce timeout; if the
2772 * connection isn't stable by then it returns -ETIMEDOUT. It checks
2773 * every 25ms for transient disconnects. When the port status has been
2774 * unchanged for 100ms it returns the port status.
2776 static int hub_port_debounce(struct usb_hub *hub, int port1)
2779 int total_time, stable_time = 0;
2780 u16 portchange, portstatus;
2781 unsigned connection = 0xffff;
2783 for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2784 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2788 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2789 (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2790 stable_time += HUB_DEBOUNCE_STEP;
2791 if (stable_time >= HUB_DEBOUNCE_STABLE)
2795 connection = portstatus & USB_PORT_STAT_CONNECTION;
2798 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2799 clear_port_feature(hub->hdev, port1,
2800 USB_PORT_FEAT_C_CONNECTION);
2803 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2805 msleep(HUB_DEBOUNCE_STEP);
2808 dev_dbg (hub->intfdev,
2809 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2810 port1, total_time, stable_time, portstatus);
2812 if (stable_time < HUB_DEBOUNCE_STABLE)
2817 void usb_ep0_reinit(struct usb_device *udev)
2819 usb_disable_endpoint(udev, 0 + USB_DIR_IN, true);
2820 usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true);
2821 usb_enable_endpoint(udev, &udev->ep0, true);
2823 EXPORT_SYMBOL_GPL(usb_ep0_reinit);
2825 #define usb_sndaddr0pipe() (PIPE_CONTROL << 30)
2826 #define usb_rcvaddr0pipe() ((PIPE_CONTROL << 30) | USB_DIR_IN)
2828 static int hub_set_address(struct usb_device *udev, int devnum)
2831 struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2834 * The host controller will choose the device address,
2835 * instead of the core having chosen it earlier
2837 if (!hcd->driver->address_device && devnum <= 1)
2839 if (udev->state == USB_STATE_ADDRESS)
2841 if (udev->state != USB_STATE_DEFAULT)
2843 if (hcd->driver->address_device)
2844 retval = hcd->driver->address_device(hcd, udev);
2846 retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2847 USB_REQ_SET_ADDRESS, 0, devnum, 0,
2848 NULL, 0, USB_CTRL_SET_TIMEOUT);
2850 update_devnum(udev, devnum);
2851 /* Device now using proper address. */
2852 usb_set_device_state(udev, USB_STATE_ADDRESS);
2853 usb_ep0_reinit(udev);
2858 /* Reset device, (re)assign address, get device descriptor.
2859 * Device connection must be stable, no more debouncing needed.
2860 * Returns device in USB_STATE_ADDRESS, except on error.
2862 * If this is called for an already-existing device (as part of
2863 * usb_reset_and_verify_device), the caller must own the device lock. For a
2864 * newly detected device that is not accessible through any global
2865 * pointers, it's not necessary to lock the device.
2868 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2871 static DEFINE_MUTEX(usb_address0_mutex);
2873 struct usb_device *hdev = hub->hdev;
2874 struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
2876 unsigned delay = HUB_SHORT_RESET_TIME;
2877 enum usb_device_speed oldspeed = udev->speed;
2879 int devnum = udev->devnum;
2881 /* root hub ports have a slightly longer reset period
2882 * (from USB 2.0 spec, section 7.1.7.5)
2884 if (!hdev->parent) {
2885 delay = HUB_ROOT_RESET_TIME;
2886 if (port1 == hdev->bus->otg_port)
2887 hdev->bus->b_hnp_enable = 0;
2890 /* Some low speed devices have problems with the quick delay, so */
2891 /* be a bit pessimistic with those devices. RHbug #23670 */
2892 if (oldspeed == USB_SPEED_LOW)
2893 delay = HUB_LONG_RESET_TIME;
2895 mutex_lock(&usb_address0_mutex);
2897 /* Reset the device; full speed may morph to high speed */
2898 /* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */
2899 retval = hub_port_reset(hub, port1, udev, delay, false);
2900 if (retval < 0) /* error or disconnect */
2902 /* success, speed is known */
2906 if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2907 dev_dbg(&udev->dev, "device reset changed speed!\n");
2910 oldspeed = udev->speed;
2912 /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2913 * it's fixed size except for full speed devices.
2914 * For Wireless USB devices, ep0 max packet is always 512 (tho
2915 * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
2917 switch (udev->speed) {
2918 case USB_SPEED_SUPER:
2919 case USB_SPEED_WIRELESS: /* fixed at 512 */
2920 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
2922 case USB_SPEED_HIGH: /* fixed at 64 */
2923 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
2925 case USB_SPEED_FULL: /* 8, 16, 32, or 64 */
2926 /* to determine the ep0 maxpacket size, try to read
2927 * the device descriptor to get bMaxPacketSize0 and
2928 * then correct our initial guess.
2930 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
2932 case USB_SPEED_LOW: /* fixed at 8 */
2933 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(8);
2939 if (udev->speed == USB_SPEED_WIRELESS)
2940 speed = "variable speed Wireless";
2942 speed = usb_speed_string(udev->speed);
2944 if (udev->speed != USB_SPEED_SUPER)
2945 dev_info(&udev->dev,
2946 "%s %s USB device number %d using %s\n",
2947 (udev->config) ? "reset" : "new", speed,
2948 devnum, udev->bus->controller->driver->name);
2950 /* Set up TT records, if needed */
2952 udev->tt = hdev->tt;
2953 udev->ttport = hdev->ttport;
2954 } else if (udev->speed != USB_SPEED_HIGH
2955 && hdev->speed == USB_SPEED_HIGH) {
2957 dev_err(&udev->dev, "parent hub has no TT\n");
2961 udev->tt = &hub->tt;
2962 udev->ttport = port1;
2965 /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2966 * Because device hardware and firmware is sometimes buggy in
2967 * this area, and this is how Linux has done it for ages.
2968 * Change it cautiously.
2970 * NOTE: If USE_NEW_SCHEME() is true we will start by issuing
2971 * a 64-byte GET_DESCRIPTOR request. This is what Windows does,
2972 * so it may help with some non-standards-compliant devices.
2973 * Otherwise we start with SET_ADDRESS and then try to read the
2974 * first 8 bytes of the device descriptor to get the ep0 maxpacket
2977 for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2978 if (USE_NEW_SCHEME(retry_counter) && !(hcd->driver->flags & HCD_USB3)) {
2979 struct usb_device_descriptor *buf;
2982 #define GET_DESCRIPTOR_BUFSIZE 64
2983 buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2989 /* Retry on all errors; some devices are flakey.
2990 * 255 is for WUSB devices, we actually need to use
2991 * 512 (WUSB1.0[4.8.1]).
2993 for (j = 0; j < 3; ++j) {
2994 buf->bMaxPacketSize0 = 0;
2995 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2996 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2997 USB_DT_DEVICE << 8, 0,
2998 buf, GET_DESCRIPTOR_BUFSIZE,
2999 initial_descriptor_timeout);
3000 switch (buf->bMaxPacketSize0) {
3001 case 8: case 16: case 32: case 64: case 255:
3002 if (buf->bDescriptorType ==
3016 udev->descriptor.bMaxPacketSize0 =
3017 buf->bMaxPacketSize0;
3020 retval = hub_port_reset(hub, port1, udev, delay, false);
3021 if (retval < 0) /* error or disconnect */
3023 if (oldspeed != udev->speed) {
3025 "device reset changed speed!\n");
3031 "device descriptor read/64, error %d\n",
3036 #undef GET_DESCRIPTOR_BUFSIZE
3040 * If device is WUSB, we already assigned an
3041 * unauthorized address in the Connect Ack sequence;
3042 * authorization will assign the final address.
3044 if (udev->wusb == 0) {
3045 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
3046 retval = hub_set_address(udev, devnum);
3053 "device not accepting address %d, error %d\n",
3057 if (udev->speed == USB_SPEED_SUPER) {
3058 devnum = udev->devnum;
3059 dev_info(&udev->dev,
3060 "%s SuperSpeed USB device number %d using %s\n",
3061 (udev->config) ? "reset" : "new",
3062 devnum, udev->bus->controller->driver->name);
3065 /* cope with hardware quirkiness:
3066 * - let SET_ADDRESS settle, some device hardware wants it
3067 * - read ep0 maxpacket even for high and low speed,
3070 if (USE_NEW_SCHEME(retry_counter) && !(hcd->driver->flags & HCD_USB3))
3074 retval = usb_get_device_descriptor(udev, 8);
3077 "device descriptor read/8, error %d\n",
3090 * Some superspeed devices have finished the link training process
3091 * and attached to a superspeed hub port, but the device descriptor
3092 * got from those devices show they aren't superspeed devices. Warm
3093 * reset the port attached by the devices can fix them.
3095 if ((udev->speed == USB_SPEED_SUPER) &&
3096 (le16_to_cpu(udev->descriptor.bcdUSB) < 0x0300)) {
3097 dev_err(&udev->dev, "got a wrong device descriptor, "
3098 "warm reset device\n");
3099 hub_port_reset(hub, port1, udev,
3100 HUB_BH_RESET_TIME, true);
3105 if (udev->descriptor.bMaxPacketSize0 == 0xff ||
3106 udev->speed == USB_SPEED_SUPER)
3109 i = udev->descriptor.bMaxPacketSize0;
3110 if (usb_endpoint_maxp(&udev->ep0.desc) != i) {
3111 if (udev->speed == USB_SPEED_LOW ||
3112 !(i == 8 || i == 16 || i == 32 || i == 64)) {
3113 dev_err(&udev->dev, "Invalid ep0 maxpacket: %d\n", i);
3117 if (udev->speed == USB_SPEED_FULL)
3118 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
3120 dev_warn(&udev->dev, "Using ep0 maxpacket: %d\n", i);
3121 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
3122 usb_ep0_reinit(udev);
3125 retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
3126 if (retval < (signed)sizeof(udev->descriptor)) {
3127 dev_err(&udev->dev, "device descriptor read/all, error %d\n",
3134 if (udev->wusb == 0 && le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0201) {
3135 retval = usb_get_bos_descriptor(udev);
3137 if (udev->bos->ext_cap && (USB_LPM_SUPPORT &
3138 le32_to_cpu(udev->bos->ext_cap->bmAttributes)))
3139 udev->lpm_capable = 1;
3144 /* notify HCD that we have a device connected and addressed */
3145 if (hcd->driver->update_device)
3146 hcd->driver->update_device(hcd, udev);
3149 hub_port_disable(hub, port1, 0);
3150 update_devnum(udev, devnum); /* for disconnect processing */
3152 mutex_unlock(&usb_address0_mutex);
3157 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
3159 struct usb_qualifier_descriptor *qual;
3162 qual = kmalloc (sizeof *qual, GFP_KERNEL);
3166 status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
3167 qual, sizeof *qual);
3168 if (status == sizeof *qual) {
3169 dev_info(&udev->dev, "not running at top speed; "
3170 "connect to a high speed hub\n");
3171 /* hub LEDs are probably harder to miss than syslog */
3172 if (hub->has_indicators) {
3173 hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
3174 schedule_delayed_work (&hub->leds, 0);
3181 hub_power_remaining (struct usb_hub *hub)
3183 struct usb_device *hdev = hub->hdev;
3187 if (!hub->limited_power)
3190 remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
3191 for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
3192 struct usb_device *udev = hdev->children[port1 - 1];
3198 /* Unconfigured devices may not use more than 100mA,
3199 * or 8mA for OTG ports */
3200 if (udev->actconfig)
3201 delta = udev->actconfig->desc.bMaxPower * 2;
3202 else if (port1 != udev->bus->otg_port || hdev->parent)
3206 if (delta > hub->mA_per_port)
3207 dev_warn(&udev->dev,
3208 "%dmA is over %umA budget for port %d!\n",
3209 delta, hub->mA_per_port, port1);
3212 if (remaining < 0) {
3213 dev_warn(hub->intfdev, "%dmA over power budget!\n",
3220 /* Handle physical or logical connection change events.
3221 * This routine is called when:
3222 * a port connection-change occurs;
3223 * a port enable-change occurs (often caused by EMI);
3224 * usb_reset_and_verify_device() encounters changed descriptors (as from
3225 * a firmware download)
3226 * caller already locked the hub
3228 static void hub_port_connect_change(struct usb_hub *hub, int port1,
3229 u16 portstatus, u16 portchange)
3231 struct usb_device *hdev = hub->hdev;
3232 struct device *hub_dev = hub->intfdev;
3233 struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
3234 unsigned wHubCharacteristics =
3235 le16_to_cpu(hub->descriptor->wHubCharacteristics);
3236 struct usb_device *udev;
3240 "port %d, status %04x, change %04x, %s\n",
3241 port1, portstatus, portchange, portspeed(hub, portstatus));
3243 if (hub->has_indicators) {
3244 set_port_led(hub, port1, HUB_LED_AUTO);
3245 hub->indicator[port1-1] = INDICATOR_AUTO;
3248 #ifdef CONFIG_USB_OTG
3249 /* during HNP, don't repeat the debounce */
3250 if (hdev->bus->is_b_host)
3251 portchange &= ~(USB_PORT_STAT_C_CONNECTION |
3252 USB_PORT_STAT_C_ENABLE);
3255 /* Try to resuscitate an existing device */
3256 udev = hdev->children[port1-1];
3257 if ((portstatus & USB_PORT_STAT_CONNECTION) && udev &&
3258 udev->state != USB_STATE_NOTATTACHED) {
3259 usb_lock_device(udev);
3260 if (portstatus & USB_PORT_STAT_ENABLE) {
3261 status = 0; /* Nothing to do */
3263 #ifdef CONFIG_USB_SUSPEND
3264 } else if (udev->state == USB_STATE_SUSPENDED &&
3265 udev->persist_enabled) {
3266 /* For a suspended device, treat this as a
3267 * remote wakeup event.
3269 status = usb_remote_wakeup(udev);
3273 status = -ENODEV; /* Don't resuscitate */
3275 usb_unlock_device(udev);
3278 clear_bit(port1, hub->change_bits);
3283 /* Disconnect any existing devices under this port */
3285 usb_disconnect(&hdev->children[port1-1]);
3286 clear_bit(port1, hub->change_bits);
3288 /* We can forget about a "removed" device when there's a physical
3289 * disconnect or the connect status changes.
3291 if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
3292 (portchange & USB_PORT_STAT_C_CONNECTION))
3293 clear_bit(port1, hub->removed_bits);
3295 if (portchange & (USB_PORT_STAT_C_CONNECTION |
3296 USB_PORT_STAT_C_ENABLE)) {
3297 status = hub_port_debounce(hub, port1);
3299 if (printk_ratelimit())
3300 dev_err(hub_dev, "connect-debounce failed, "
3301 "port %d disabled\n", port1);
3302 portstatus &= ~USB_PORT_STAT_CONNECTION;
3304 portstatus = status;
3308 /* Return now if debouncing failed or nothing is connected or
3309 * the device was "removed".
3311 if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
3312 test_bit(port1, hub->removed_bits)) {
3314 /* maybe switch power back on (e.g. root hub was reset) */
3315 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
3316 && !port_is_power_on(hub, portstatus))
3317 set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
3319 if (portstatus & USB_PORT_STAT_ENABLE)
3324 for (i = 0; i < SET_CONFIG_TRIES; i++) {
3326 /* reallocate for each attempt, since references
3327 * to the previous one can escape in various ways
3329 udev = usb_alloc_dev(hdev, hdev->bus, port1);
3332 "couldn't allocate port %d usb_device\n",
3337 usb_set_device_state(udev, USB_STATE_POWERED);
3338 udev->bus_mA = hub->mA_per_port;
3339 udev->level = hdev->level + 1;
3340 udev->wusb = hub_is_wusb(hub);
3342 /* Only USB 3.0 devices are connected to SuperSpeed hubs. */
3343 if (hub_is_superspeed(hub->hdev))
3344 udev->speed = USB_SPEED_SUPER;
3346 udev->speed = USB_SPEED_UNKNOWN;
3348 choose_devnum(udev);
3349 if (udev->devnum <= 0) {
3350 status = -ENOTCONN; /* Don't retry */
3354 /* reset (non-USB 3.0 devices) and get descriptor */
3355 status = hub_port_init(hub, udev, port1, i);
3359 usb_detect_quirks(udev);
3360 if (udev->quirks & USB_QUIRK_DELAY_INIT)
3363 /* consecutive bus-powered hubs aren't reliable; they can
3364 * violate the voltage drop budget. if the new child has
3365 * a "powered" LED, users should notice we didn't enable it
3366 * (without reading syslog), even without per-port LEDs
3369 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
3370 && udev->bus_mA <= 100) {
3373 status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
3376 dev_dbg(&udev->dev, "get status %d ?\n", status);
3379 le16_to_cpus(&devstat);
3380 if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
3382 "can't connect bus-powered hub "
3384 if (hub->has_indicators) {
3385 hub->indicator[port1-1] =
3386 INDICATOR_AMBER_BLINK;
3387 schedule_delayed_work (&hub->leds, 0);
3389 status = -ENOTCONN; /* Don't retry */
3394 /* check for devices running slower than they could */
3395 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
3396 && udev->speed == USB_SPEED_FULL
3397 && highspeed_hubs != 0)
3398 check_highspeed (hub, udev, port1);
3400 /* Store the parent's children[] pointer. At this point
3401 * udev becomes globally accessible, although presumably
3402 * no one will look at it until hdev is unlocked.
3406 /* We mustn't add new devices if the parent hub has
3407 * been disconnected; we would race with the
3408 * recursively_mark_NOTATTACHED() routine.
3410 spin_lock_irq(&device_state_lock);
3411 if (hdev->state == USB_STATE_NOTATTACHED)
3414 hdev->children[port1-1] = udev;
3415 spin_unlock_irq(&device_state_lock);
3417 /* Run it through the hoops (find a driver, etc) */
3419 status = usb_new_device(udev);
3421 spin_lock_irq(&device_state_lock);
3422 hdev->children[port1-1] = NULL;
3423 spin_unlock_irq(&device_state_lock);
3430 status = hub_power_remaining(hub);
3432 dev_dbg(hub_dev, "%dmA power budget left\n", status);
3437 hub_port_disable(hub, port1, 1);
3439 usb_ep0_reinit(udev);
3440 release_devnum(udev);
3443 if ((status == -ENOTCONN) || (status == -ENOTSUPP))
3446 if (hub->hdev->parent ||
3447 !hcd->driver->port_handed_over ||
3448 !(hcd->driver->port_handed_over)(hcd, port1))
3449 dev_err(hub_dev, "unable to enumerate USB device on port %d\n",
3453 hub_port_disable(hub, port1, 1);
3454 if (hcd->driver->relinquish_port && !hub->hdev->parent)
3455 hcd->driver->relinquish_port(hcd, port1);
3458 static void hub_events(void)
3460 struct list_head *tmp;
3461 struct usb_device *hdev;
3462 struct usb_interface *intf;
3463 struct usb_hub *hub;
3464 struct device *hub_dev;
3473 * We restart the list every time to avoid a deadlock with
3474 * deleting hubs downstream from this one. This should be
3475 * safe since we delete the hub from the event list.
3476 * Not the most efficient, but avoids deadlocks.
3480 /* Grab the first entry at the beginning of the list */
3481 spin_lock_irq(&hub_event_lock);
3482 if (list_empty(&hub_event_list)) {
3483 spin_unlock_irq(&hub_event_lock);
3487 tmp = hub_event_list.next;
3490 hub = list_entry(tmp, struct usb_hub, event_list);
3491 kref_get(&hub->kref);
3492 spin_unlock_irq(&hub_event_lock);
3495 hub_dev = hub->intfdev;
3496 intf = to_usb_interface(hub_dev);
3497 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
3498 hdev->state, hub->descriptor
3499 ? hub->descriptor->bNbrPorts
3501 /* NOTE: expects max 15 ports... */
3502 (u16) hub->change_bits[0],
3503 (u16) hub->event_bits[0]);
3505 /* Lock the device, then check to see if we were
3506 * disconnected while waiting for the lock to succeed. */
3507 usb_lock_device(hdev);
3508 if (unlikely(hub->disconnected))
3509 goto loop_disconnected;
3511 /* If the hub has died, clean up after it */
3512 if (hdev->state == USB_STATE_NOTATTACHED) {
3513 hub->error = -ENODEV;
3514 hub_quiesce(hub, HUB_DISCONNECT);
3519 ret = usb_autopm_get_interface(intf);
3521 dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
3525 /* If this is an inactive hub, do nothing */
3530 dev_dbg (hub_dev, "resetting for error %d\n",
3533 ret = usb_reset_device(hdev);
3536 "error resetting hub: %d\n", ret);
3544 /* deal with port status changes */
3545 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
3546 if (test_bit(i, hub->busy_bits))
3548 connect_change = test_bit(i, hub->change_bits);
3549 if (!test_and_clear_bit(i, hub->event_bits) &&
3553 ret = hub_port_status(hub, i,
3554 &portstatus, &portchange);
3558 if (portchange & USB_PORT_STAT_C_CONNECTION) {
3559 clear_port_feature(hdev, i,
3560 USB_PORT_FEAT_C_CONNECTION);
3564 if (portchange & USB_PORT_STAT_C_ENABLE) {
3565 if (!connect_change)
3567 "port %d enable change, "
3570 clear_port_feature(hdev, i,
3571 USB_PORT_FEAT_C_ENABLE);
3574 * EM interference sometimes causes badly
3575 * shielded USB devices to be shutdown by
3576 * the hub, this hack enables them again.
3577 * Works at least with mouse driver.
3579 if (!(portstatus & USB_PORT_STAT_ENABLE)
3581 && hdev->children[i-1]) {
3584 "disabled by hub (EMI?), "
3591 if (portchange & USB_PORT_STAT_C_SUSPEND) {
3592 struct usb_device *udev;
3594 clear_port_feature(hdev, i,
3595 USB_PORT_FEAT_C_SUSPEND);
3596 udev = hdev->children[i-1];
3598 /* TRSMRCY = 10 msec */
3601 usb_lock_device(udev);
3602 ret = usb_remote_wakeup(hdev->
3604 usb_unlock_device(udev);
3609 hub_port_disable(hub, i, 1);
3612 "resume on port %d, status %d\n",
3616 if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
3620 dev_dbg(hub_dev, "over-current change on port "
3622 clear_port_feature(hdev, i,
3623 USB_PORT_FEAT_C_OVER_CURRENT);
3624 msleep(100); /* Cool down */
3625 hub_power_on(hub, true);
3626 hub_port_status(hub, i, &status, &unused);
3627 if (status & USB_PORT_STAT_OVERCURRENT)
3628 dev_err(hub_dev, "over-current "
3629 "condition on port %d\n", i);
3632 if (portchange & USB_PORT_STAT_C_RESET) {
3634 "reset change on port %d\n",
3636 clear_port_feature(hdev, i,
3637 USB_PORT_FEAT_C_RESET);
3639 if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
3640 hub_is_superspeed(hub->hdev)) {
3642 "warm reset change on port %d\n",
3644 clear_port_feature(hdev, i,
3645 USB_PORT_FEAT_C_BH_PORT_RESET);
3647 if (portchange & USB_PORT_STAT_C_LINK_STATE) {
3648 clear_port_feature(hub->hdev, i,
3649 USB_PORT_FEAT_C_PORT_LINK_STATE);
3651 if (portchange & USB_PORT_STAT_C_CONFIG_ERROR) {
3653 "config error on port %d\n",
3655 clear_port_feature(hub->hdev, i,
3656 USB_PORT_FEAT_C_PORT_CONFIG_ERROR);
3659 /* Warm reset a USB3 protocol port if it's in
3660 * SS.Inactive state.
3662 if (hub_port_warm_reset_required(hub, portstatus)) {
3663 dev_dbg(hub_dev, "warm reset port %d\n", i);
3664 hub_port_reset(hub, i, NULL,
3665 HUB_BH_RESET_TIME, true);
3669 hub_port_connect_change(hub, i,
3670 portstatus, portchange);
3673 /* deal with hub status changes */
3674 if (test_and_clear_bit(0, hub->event_bits) == 0)
3676 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
3677 dev_err (hub_dev, "get_hub_status failed\n");
3679 if (hubchange & HUB_CHANGE_LOCAL_POWER) {
3680 dev_dbg (hub_dev, "power change\n");
3681 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
3682 if (hubstatus & HUB_STATUS_LOCAL_POWER)
3683 /* FIXME: Is this always true? */
3684 hub->limited_power = 1;
3686 hub->limited_power = 0;
3688 if (hubchange & HUB_CHANGE_OVERCURRENT) {
3692 dev_dbg(hub_dev, "over-current change\n");
3693 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
3694 msleep(500); /* Cool down */
3695 hub_power_on(hub, true);
3696 hub_hub_status(hub, &status, &unused);
3697 if (status & HUB_STATUS_OVERCURRENT)
3698 dev_err(hub_dev, "over-current "
3704 /* Balance the usb_autopm_get_interface() above */
3705 usb_autopm_put_interface_no_suspend(intf);
3707 /* Balance the usb_autopm_get_interface_no_resume() in
3708 * kick_khubd() and allow autosuspend.
3710 usb_autopm_put_interface(intf);
3712 usb_unlock_device(hdev);
3713 kref_put(&hub->kref, hub_release);
3715 } /* end while (1) */
3718 static int hub_thread(void *__unused)
3720 /* khubd needs to be freezable to avoid intefering with USB-PERSIST
3721 * port handover. Otherwise it might see that a full-speed device
3722 * was gone before the EHCI controller had handed its port over to
3723 * the companion full-speed controller.
3729 wait_event_freezable(khubd_wait,
3730 !list_empty(&hub_event_list) ||
3731 kthread_should_stop());
3732 } while (!kthread_should_stop() || !list_empty(&hub_event_list));
3734 pr_debug("%s: khubd exiting\n", usbcore_name);
3738 static const struct usb_device_id hub_id_table[] = {
3739 { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
3740 .bDeviceClass = USB_CLASS_HUB},
3741 { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
3742 .bInterfaceClass = USB_CLASS_HUB},
3743 { } /* Terminating entry */
3746 MODULE_DEVICE_TABLE (usb, hub_id_table);
3748 static struct usb_driver hub_driver = {
3751 .disconnect = hub_disconnect,
3752 .suspend = hub_suspend,
3753 .resume = hub_resume,
3754 .reset_resume = hub_reset_resume,
3755 .pre_reset = hub_pre_reset,
3756 .post_reset = hub_post_reset,
3757 .unlocked_ioctl = hub_ioctl,
3758 .id_table = hub_id_table,
3759 .supports_autosuspend = 1,
3762 int usb_hub_init(void)
3764 if (usb_register(&hub_driver) < 0) {
3765 printk(KERN_ERR "%s: can't register hub driver\n",
3770 khubd_task = kthread_run(hub_thread, NULL, "khubd");
3771 if (!IS_ERR(khubd_task))
3774 /* Fall through if kernel_thread failed */
3775 usb_deregister(&hub_driver);
3776 printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
3781 void usb_hub_cleanup(void)
3783 kthread_stop(khubd_task);
3786 * Hub resources are freed for us by usb_deregister. It calls
3787 * usb_driver_purge on every device which in turn calls that
3788 * devices disconnect function if it is using this driver.
3789 * The hub_disconnect function takes care of releasing the
3790 * individual hub resources. -greg
3792 usb_deregister(&hub_driver);
3793 } /* usb_hub_cleanup() */
3795 static int descriptors_changed(struct usb_device *udev,
3796 struct usb_device_descriptor *old_device_descriptor)
3800 unsigned serial_len = 0;
3802 unsigned old_length;
3806 if (memcmp(&udev->descriptor, old_device_descriptor,
3807 sizeof(*old_device_descriptor)) != 0)
3810 /* Since the idVendor, idProduct, and bcdDevice values in the
3811 * device descriptor haven't changed, we will assume the
3812 * Manufacturer and Product strings haven't changed either.
3813 * But the SerialNumber string could be different (e.g., a
3814 * different flash card of the same brand).
3817 serial_len = strlen(udev->serial) + 1;
3820 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
3821 old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
3822 len = max(len, old_length);
3825 buf = kmalloc(len, GFP_NOIO);
3827 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
3828 /* assume the worst */
3831 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
3832 old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
3833 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
3835 if (length != old_length) {
3836 dev_dbg(&udev->dev, "config index %d, error %d\n",
3841 if (memcmp (buf, udev->rawdescriptors[index], old_length)
3843 dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
3845 ((struct usb_config_descriptor *) buf)->
3846 bConfigurationValue);
3852 if (!changed && serial_len) {
3853 length = usb_string(udev, udev->descriptor.iSerialNumber,
3855 if (length + 1 != serial_len) {
3856 dev_dbg(&udev->dev, "serial string error %d\n",
3859 } else if (memcmp(buf, udev->serial, length) != 0) {
3860 dev_dbg(&udev->dev, "serial string changed\n");
3870 * usb_reset_and_verify_device - perform a USB port reset to reinitialize a device
3871 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
3873 * WARNING - don't use this routine to reset a composite device
3874 * (one with multiple interfaces owned by separate drivers)!
3875 * Use usb_reset_device() instead.
3877 * Do a port reset, reassign the device's address, and establish its
3878 * former operating configuration. If the reset fails, or the device's
3879 * descriptors change from their values before the reset, or the original
3880 * configuration and altsettings cannot be restored, a flag will be set
3881 * telling khubd to pretend the device has been disconnected and then
3882 * re-connected. All drivers will be unbound, and the device will be
3883 * re-enumerated and probed all over again.
3885 * Returns 0 if the reset succeeded, -ENODEV if the device has been
3886 * flagged for logical disconnection, or some other negative error code
3887 * if the reset wasn't even attempted.
3889 * The caller must own the device lock. For example, it's safe to use
3890 * this from a driver probe() routine after downloading new firmware.
3891 * For calls that might not occur during probe(), drivers should lock
3892 * the device using usb_lock_device_for_reset().
3894 * Locking exception: This routine may also be called from within an
3895 * autoresume handler. Such usage won't conflict with other tasks
3896 * holding the device lock because these tasks should always call
3897 * usb_autopm_resume_device(), thereby preventing any unwanted autoresume.
3899 static int usb_reset_and_verify_device(struct usb_device *udev)
3901 struct usb_device *parent_hdev = udev->parent;
3902 struct usb_hub *parent_hub;
3903 struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3904 struct usb_device_descriptor descriptor = udev->descriptor;
3906 int port1 = udev->portnum;
3908 if (udev->state == USB_STATE_NOTATTACHED ||
3909 udev->state == USB_STATE_SUSPENDED) {
3910 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3916 /* this requires hcd-specific logic; see ohci_restart() */
3917 dev_dbg(&udev->dev, "%s for root hub!\n", __func__);
3920 parent_hub = hdev_to_hub(parent_hdev);
3922 set_bit(port1, parent_hub->busy_bits);
3923 for (i = 0; i < SET_CONFIG_TRIES; ++i) {
3925 /* ep0 maxpacket size may change; let the HCD know about it.
3926 * Other endpoints will be handled by re-enumeration. */
3927 usb_ep0_reinit(udev);
3928 ret = hub_port_init(parent_hub, udev, port1, i);
3929 if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
3932 clear_bit(port1, parent_hub->busy_bits);
3937 /* Device might have changed firmware (DFU or similar) */
3938 if (descriptors_changed(udev, &descriptor)) {
3939 dev_info(&udev->dev, "device firmware changed\n");
3940 udev->descriptor = descriptor; /* for disconnect() calls */
3944 /* Restore the device's previous configuration */
3945 if (!udev->actconfig)
3948 mutex_lock(hcd->bandwidth_mutex);
3949 ret = usb_hcd_alloc_bandwidth(udev, udev->actconfig, NULL, NULL);
3951 dev_warn(&udev->dev,
3952 "Busted HC? Not enough HCD resources for "
3953 "old configuration.\n");
3954 mutex_unlock(hcd->bandwidth_mutex);
3957 ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3958 USB_REQ_SET_CONFIGURATION, 0,
3959 udev->actconfig->desc.bConfigurationValue, 0,
3960 NULL, 0, USB_CTRL_SET_TIMEOUT);
3963 "can't restore configuration #%d (error=%d)\n",
3964 udev->actconfig->desc.bConfigurationValue, ret);
3965 mutex_unlock(hcd->bandwidth_mutex);
3968 mutex_unlock(hcd->bandwidth_mutex);
3969 usb_set_device_state(udev, USB_STATE_CONFIGURED);
3971 /* Put interfaces back into the same altsettings as before.
3972 * Don't bother to send the Set-Interface request for interfaces
3973 * that were already in altsetting 0; besides being unnecessary,
3974 * many devices can't handle it. Instead just reset the host-side
3977 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3978 struct usb_host_config *config = udev->actconfig;
3979 struct usb_interface *intf = config->interface[i];
3980 struct usb_interface_descriptor *desc;
3982 desc = &intf->cur_altsetting->desc;
3983 if (desc->bAlternateSetting == 0) {
3984 usb_disable_interface(udev, intf, true);
3985 usb_enable_interface(udev, intf, true);
3988 /* Let the bandwidth allocation function know that this
3989 * device has been reset, and it will have to use
3990 * alternate setting 0 as the current alternate setting.
3992 intf->resetting_device = 1;
3993 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3994 desc->bAlternateSetting);
3995 intf->resetting_device = 0;
3998 dev_err(&udev->dev, "failed to restore interface %d "
3999 "altsetting %d (error=%d)\n",
4000 desc->bInterfaceNumber,
4001 desc->bAlternateSetting,
4011 hub_port_logical_disconnect(parent_hub, port1);
4016 * usb_reset_device - warn interface drivers and perform a USB port reset
4017 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
4019 * Warns all drivers bound to registered interfaces (using their pre_reset
4020 * method), performs the port reset, and then lets the drivers know that
4021 * the reset is over (using their post_reset method).
4023 * Return value is the same as for usb_reset_and_verify_device().
4025 * The caller must own the device lock. For example, it's safe to use
4026 * this from a driver probe() routine after downloading new firmware.
4027 * For calls that might not occur during probe(), drivers should lock
4028 * the device using usb_lock_device_for_reset().
4030 * If an interface is currently being probed or disconnected, we assume
4031 * its driver knows how to handle resets. For all other interfaces,
4032 * if the driver doesn't have pre_reset and post_reset methods then
4033 * we attempt to unbind it and rebind afterward.
4035 int usb_reset_device(struct usb_device *udev)
4039 struct usb_host_config *config = udev->actconfig;
4041 if (udev->state == USB_STATE_NOTATTACHED ||
4042 udev->state == USB_STATE_SUSPENDED) {
4043 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
4048 /* Prevent autosuspend during the reset */
4049 usb_autoresume_device(udev);
4052 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
4053 struct usb_interface *cintf = config->interface[i];
4054 struct usb_driver *drv;
4057 if (cintf->dev.driver) {
4058 drv = to_usb_driver(cintf->dev.driver);
4059 if (drv->pre_reset && drv->post_reset)
4060 unbind = (drv->pre_reset)(cintf);
4061 else if (cintf->condition ==
4062 USB_INTERFACE_BOUND)
4065 usb_forced_unbind_intf(cintf);
4070 ret = usb_reset_and_verify_device(udev);
4073 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
4074 struct usb_interface *cintf = config->interface[i];
4075 struct usb_driver *drv;
4076 int rebind = cintf->needs_binding;
4078 if (!rebind && cintf->dev.driver) {
4079 drv = to_usb_driver(cintf->dev.driver);
4080 if (drv->post_reset)
4081 rebind = (drv->post_reset)(cintf);
4082 else if (cintf->condition ==
4083 USB_INTERFACE_BOUND)
4086 if (ret == 0 && rebind)
4087 usb_rebind_intf(cintf);
4091 usb_autosuspend_device(udev);
4094 EXPORT_SYMBOL_GPL(usb_reset_device);
4098 * usb_queue_reset_device - Reset a USB device from an atomic context
4099 * @iface: USB interface belonging to the device to reset
4101 * This function can be used to reset a USB device from an atomic
4102 * context, where usb_reset_device() won't work (as it blocks).
4104 * Doing a reset via this method is functionally equivalent to calling
4105 * usb_reset_device(), except for the fact that it is delayed to a
4106 * workqueue. This means that any drivers bound to other interfaces
4107 * might be unbound, as well as users from usbfs in user space.
4111 * - Scheduling two resets at the same time from two different drivers
4112 * attached to two different interfaces of the same device is
4113 * possible; depending on how the driver attached to each interface
4114 * handles ->pre_reset(), the second reset might happen or not.
4116 * - If a driver is unbound and it had a pending reset, the reset will
4119 * - This function can be called during .probe() or .disconnect()
4120 * times. On return from .disconnect(), any pending resets will be
4123 * There is no no need to lock/unlock the @reset_ws as schedule_work()
4126 * NOTE: We don't do any reference count tracking because it is not
4127 * needed. The lifecycle of the work_struct is tied to the
4128 * usb_interface. Before destroying the interface we cancel the
4129 * work_struct, so the fact that work_struct is queued and or
4130 * running means the interface (and thus, the device) exist and
4133 void usb_queue_reset_device(struct usb_interface *iface)
4135 schedule_work(&iface->reset_ws);
4137 EXPORT_SYMBOL_GPL(usb_queue_reset_device);