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/kthread.h>
23 #include <linux/mutex.h>
24 #include <linux/freezer.h>
26 #include <asm/uaccess.h>
27 #include <asm/byteorder.h>
33 /* if we are in debug mode, always announce new devices */
35 #ifndef CONFIG_USB_ANNOUNCE_NEW_DEVICES
36 #define CONFIG_USB_ANNOUNCE_NEW_DEVICES
41 struct device *intfdev; /* the "interface" device */
42 struct usb_device *hdev;
44 struct urb *urb; /* for interrupt polling pipe */
46 /* buffer for urb ... with extra space in case of babble */
48 dma_addr_t buffer_dma; /* DMA address for buffer */
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 #if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
65 #error event_bits[] is too short!
68 struct usb_hub_descriptor *descriptor; /* class descriptor */
69 struct usb_tt tt; /* Transaction Translator */
71 unsigned mA_per_port; /* current for each child */
73 unsigned limited_power:1;
75 unsigned activating:1;
76 unsigned disconnected:1;
78 unsigned has_indicators:1;
79 u8 indicator[USB_MAXCHILDREN];
80 struct delayed_work leds;
84 /* Protect struct usb_device->state and ->children members
85 * Note: Both are also protected by ->dev.sem, except that ->state can
86 * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
87 static DEFINE_SPINLOCK(device_state_lock);
89 /* khubd's worklist and its lock */
90 static DEFINE_SPINLOCK(hub_event_lock);
91 static LIST_HEAD(hub_event_list); /* List of hubs needing servicing */
94 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
96 static struct task_struct *khubd_task;
98 /* cycle leds on hubs that aren't blinking for attention */
99 static int blinkenlights = 0;
100 module_param (blinkenlights, bool, S_IRUGO);
101 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
104 * As of 2.6.10 we introduce a new USB device initialization scheme which
105 * closely resembles the way Windows works. Hopefully it will be compatible
106 * with a wider range of devices than the old scheme. However some previously
107 * working devices may start giving rise to "device not accepting address"
108 * errors; if that happens the user can try the old scheme by adjusting the
109 * following module parameters.
111 * For maximum flexibility there are two boolean parameters to control the
112 * hub driver's behavior. On the first initialization attempt, if the
113 * "old_scheme_first" parameter is set then the old scheme will be used,
114 * otherwise the new scheme is used. If that fails and "use_both_schemes"
115 * is set, then the driver will make another attempt, using the other scheme.
117 static int old_scheme_first = 0;
118 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
119 MODULE_PARM_DESC(old_scheme_first,
120 "start with the old device initialization scheme");
122 static int use_both_schemes = 1;
123 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
124 MODULE_PARM_DESC(use_both_schemes,
125 "try the other device initialization scheme if the "
128 /* Mutual exclusion for EHCI CF initialization. This interferes with
129 * port reset on some companion controllers.
131 DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
132 EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
135 static inline char *portspeed(int portstatus)
137 if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
139 else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
145 /* Note that hdev or one of its children must be locked! */
146 static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
148 return usb_get_intfdata(hdev->actconfig->interface[0]);
151 /* USB 2.0 spec Section 11.24.4.5 */
152 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
156 for (i = 0; i < 3; i++) {
157 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
158 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
159 USB_DT_HUB << 8, 0, data, size,
160 USB_CTRL_GET_TIMEOUT);
161 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
168 * USB 2.0 spec Section 11.24.2.1
170 static int clear_hub_feature(struct usb_device *hdev, int feature)
172 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
173 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
177 * USB 2.0 spec Section 11.24.2.2
179 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
181 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
182 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
187 * USB 2.0 spec Section 11.24.2.13
189 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
191 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
192 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
197 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
198 * for info about using port indicators
200 static void set_port_led(
206 int status = set_port_feature(hub->hdev, (selector << 8) | port1,
207 USB_PORT_FEAT_INDICATOR);
209 dev_dbg (hub->intfdev,
210 "port %d indicator %s status %d\n",
212 ({ char *s; switch (selector) {
213 case HUB_LED_AMBER: s = "amber"; break;
214 case HUB_LED_GREEN: s = "green"; break;
215 case HUB_LED_OFF: s = "off"; break;
216 case HUB_LED_AUTO: s = "auto"; break;
217 default: s = "??"; break;
222 #define LED_CYCLE_PERIOD ((2*HZ)/3)
224 static void led_work (struct work_struct *work)
226 struct usb_hub *hub =
227 container_of(work, struct usb_hub, leds.work);
228 struct usb_device *hdev = hub->hdev;
230 unsigned changed = 0;
233 if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
236 for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
237 unsigned selector, mode;
239 /* 30%-50% duty cycle */
241 switch (hub->indicator[i]) {
243 case INDICATOR_CYCLE:
245 selector = HUB_LED_AUTO;
246 mode = INDICATOR_AUTO;
248 /* blinking green = sw attention */
249 case INDICATOR_GREEN_BLINK:
250 selector = HUB_LED_GREEN;
251 mode = INDICATOR_GREEN_BLINK_OFF;
253 case INDICATOR_GREEN_BLINK_OFF:
254 selector = HUB_LED_OFF;
255 mode = INDICATOR_GREEN_BLINK;
257 /* blinking amber = hw attention */
258 case INDICATOR_AMBER_BLINK:
259 selector = HUB_LED_AMBER;
260 mode = INDICATOR_AMBER_BLINK_OFF;
262 case INDICATOR_AMBER_BLINK_OFF:
263 selector = HUB_LED_OFF;
264 mode = INDICATOR_AMBER_BLINK;
266 /* blink green/amber = reserved */
267 case INDICATOR_ALT_BLINK:
268 selector = HUB_LED_GREEN;
269 mode = INDICATOR_ALT_BLINK_OFF;
271 case INDICATOR_ALT_BLINK_OFF:
272 selector = HUB_LED_AMBER;
273 mode = INDICATOR_ALT_BLINK;
278 if (selector != HUB_LED_AUTO)
280 set_port_led(hub, i + 1, selector);
281 hub->indicator[i] = mode;
283 if (!changed && blinkenlights) {
285 cursor %= hub->descriptor->bNbrPorts;
286 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
287 hub->indicator[cursor] = INDICATOR_CYCLE;
291 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
294 /* use a short timeout for hub/port status fetches */
295 #define USB_STS_TIMEOUT 1000
296 #define USB_STS_RETRIES 5
299 * USB 2.0 spec Section 11.24.2.6
301 static int get_hub_status(struct usb_device *hdev,
302 struct usb_hub_status *data)
304 int i, status = -ETIMEDOUT;
306 for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
307 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
308 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
309 data, sizeof(*data), USB_STS_TIMEOUT);
315 * USB 2.0 spec Section 11.24.2.7
317 static int get_port_status(struct usb_device *hdev, int port1,
318 struct usb_port_status *data)
320 int i, status = -ETIMEDOUT;
322 for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
323 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
324 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
325 data, sizeof(*data), USB_STS_TIMEOUT);
330 static int hub_port_status(struct usb_hub *hub, int port1,
331 u16 *status, u16 *change)
335 mutex_lock(&hub->status_mutex);
336 ret = get_port_status(hub->hdev, port1, &hub->status->port);
338 dev_err(hub->intfdev,
339 "%s failed (err = %d)\n", __func__, ret);
343 *status = le16_to_cpu(hub->status->port.wPortStatus);
344 *change = le16_to_cpu(hub->status->port.wPortChange);
347 mutex_unlock(&hub->status_mutex);
351 static void kick_khubd(struct usb_hub *hub)
355 /* Suppress autosuspend until khubd runs */
356 to_usb_interface(hub->intfdev)->pm_usage_cnt = 1;
358 spin_lock_irqsave(&hub_event_lock, flags);
359 if (!hub->disconnected && list_empty(&hub->event_list)) {
360 list_add_tail(&hub->event_list, &hub_event_list);
361 wake_up(&khubd_wait);
363 spin_unlock_irqrestore(&hub_event_lock, flags);
366 void usb_kick_khubd(struct usb_device *hdev)
368 /* FIXME: What if hdev isn't bound to the hub driver? */
369 kick_khubd(hdev_to_hub(hdev));
373 /* completion function, fires on port status changes and various faults */
374 static void hub_irq(struct urb *urb)
376 struct usb_hub *hub = urb->context;
377 int status = urb->status;
382 case -ENOENT: /* synchronous unlink */
383 case -ECONNRESET: /* async unlink */
384 case -ESHUTDOWN: /* hardware going away */
387 default: /* presumably an error */
388 /* Cause a hub reset after 10 consecutive errors */
389 dev_dbg (hub->intfdev, "transfer --> %d\n", status);
390 if ((++hub->nerrors < 10) || hub->error)
395 /* let khubd handle things */
396 case 0: /* we got data: port status changed */
398 for (i = 0; i < urb->actual_length; ++i)
399 bits |= ((unsigned long) ((*hub->buffer)[i]))
401 hub->event_bits[0] = bits;
407 /* Something happened, let khubd figure it out */
414 if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
415 && status != -ENODEV && status != -EPERM)
416 dev_err (hub->intfdev, "resubmit --> %d\n", status);
419 /* USB 2.0 spec Section 11.24.2.3 */
421 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
423 return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
424 HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
429 * enumeration blocks khubd for a long time. we use keventd instead, since
430 * long blocking there is the exception, not the rule. accordingly, HCDs
431 * talking to TTs must queue control transfers (not just bulk and iso), so
432 * both can talk to the same hub concurrently.
434 static void hub_tt_kevent (struct work_struct *work)
436 struct usb_hub *hub =
437 container_of(work, struct usb_hub, tt.kevent);
441 spin_lock_irqsave (&hub->tt.lock, flags);
442 while (--limit && !list_empty (&hub->tt.clear_list)) {
443 struct list_head *temp;
444 struct usb_tt_clear *clear;
445 struct usb_device *hdev = hub->hdev;
448 temp = hub->tt.clear_list.next;
449 clear = list_entry (temp, struct usb_tt_clear, clear_list);
450 list_del (&clear->clear_list);
452 /* drop lock so HCD can concurrently report other TT errors */
453 spin_unlock_irqrestore (&hub->tt.lock, flags);
454 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
455 spin_lock_irqsave (&hub->tt.lock, flags);
459 "clear tt %d (%04x) error %d\n",
460 clear->tt, clear->devinfo, status);
463 spin_unlock_irqrestore (&hub->tt.lock, flags);
467 * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
468 * @udev: the device whose split transaction failed
469 * @pipe: identifies the endpoint of the failed transaction
471 * High speed HCDs use this to tell the hub driver that some split control or
472 * bulk transaction failed in a way that requires clearing internal state of
473 * a transaction translator. This is normally detected (and reported) from
476 * It may not be possible for that hub to handle additional full (or low)
477 * speed transactions until that state is fully cleared out.
479 void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
481 struct usb_tt *tt = udev->tt;
483 struct usb_tt_clear *clear;
485 /* we've got to cope with an arbitrary number of pending TT clears,
486 * since each TT has "at least two" buffers that can need it (and
487 * there can be many TTs per hub). even if they're uncommon.
489 if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) {
490 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
491 /* FIXME recover somehow ... RESET_TT? */
495 /* info that CLEAR_TT_BUFFER needs */
496 clear->tt = tt->multi ? udev->ttport : 1;
497 clear->devinfo = usb_pipeendpoint (pipe);
498 clear->devinfo |= udev->devnum << 4;
499 clear->devinfo |= usb_pipecontrol (pipe)
500 ? (USB_ENDPOINT_XFER_CONTROL << 11)
501 : (USB_ENDPOINT_XFER_BULK << 11);
502 if (usb_pipein (pipe))
503 clear->devinfo |= 1 << 15;
505 /* tell keventd to clear state for this TT */
506 spin_lock_irqsave (&tt->lock, flags);
507 list_add_tail (&clear->clear_list, &tt->clear_list);
508 schedule_work (&tt->kevent);
509 spin_unlock_irqrestore (&tt->lock, flags);
511 EXPORT_SYMBOL_GPL(usb_hub_tt_clear_buffer);
513 static void hub_power_on(struct usb_hub *hub)
516 unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
517 u16 wHubCharacteristics =
518 le16_to_cpu(hub->descriptor->wHubCharacteristics);
520 /* Enable power on each port. Some hubs have reserved values
521 * of LPSM (> 2) in their descriptors, even though they are
522 * USB 2.0 hubs. Some hubs do not implement port-power switching
523 * but only emulate it. In all cases, the ports won't work
524 * unless we send these messages to the hub.
526 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
527 dev_dbg(hub->intfdev, "enabling power on all ports\n");
529 dev_dbg(hub->intfdev, "trying to enable port power on "
530 "non-switchable hub\n");
531 for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
532 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
534 /* Wait at least 100 msec for power to become stable */
535 msleep(max(pgood_delay, (unsigned) 100));
538 static void hub_quiesce(struct usb_hub *hub)
540 /* (nonblocking) khubd and related activity won't re-trigger */
544 /* (blocking) stop khubd and related activity */
545 usb_kill_urb(hub->urb);
546 if (hub->has_indicators)
547 cancel_delayed_work_sync(&hub->leds);
549 cancel_work_sync(&hub->tt.kevent);
552 static void hub_activate(struct usb_hub *hub)
559 status = usb_submit_urb(hub->urb, GFP_NOIO);
561 dev_err(hub->intfdev, "activate --> %d\n", status);
562 if (hub->has_indicators && blinkenlights)
563 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
565 /* scan all ports ASAP */
569 static int hub_hub_status(struct usb_hub *hub,
570 u16 *status, u16 *change)
574 mutex_lock(&hub->status_mutex);
575 ret = get_hub_status(hub->hdev, &hub->status->hub);
577 dev_err (hub->intfdev,
578 "%s failed (err = %d)\n", __func__, ret);
580 *status = le16_to_cpu(hub->status->hub.wHubStatus);
581 *change = le16_to_cpu(hub->status->hub.wHubChange);
584 mutex_unlock(&hub->status_mutex);
588 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
590 struct usb_device *hdev = hub->hdev;
593 if (hdev->children[port1-1] && set_state)
594 usb_set_device_state(hdev->children[port1-1],
595 USB_STATE_NOTATTACHED);
597 ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
599 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
605 * Disable a port and mark a logical connnect-change event, so that some
606 * time later khubd will disconnect() any existing usb_device on the port
607 * and will re-enumerate if there actually is a device attached.
609 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
611 dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
612 hub_port_disable(hub, port1, 1);
614 /* FIXME let caller ask to power down the port:
615 * - some devices won't enumerate without a VBUS power cycle
616 * - SRP saves power that way
617 * - ... new call, TBD ...
618 * That's easy if this hub can switch power per-port, and
619 * khubd reactivates the port later (timer, SRP, etc).
620 * Powerdown must be optional, because of reset/DFU.
623 set_bit(port1, hub->change_bits);
627 /* caller has locked the hub device */
628 static void hub_stop(struct usb_hub *hub)
630 struct usb_device *hdev = hub->hdev;
633 /* Disconnect all the children */
634 for (i = 0; i < hdev->maxchild; ++i) {
635 if (hdev->children[i])
636 usb_disconnect(&hdev->children[i]);
643 #define HUB_RESET_RESUME 3
647 /* Try to identify which devices need USB-PERSIST handling */
648 static int persistent_device(struct usb_device *udev)
652 struct usb_host_config *actconfig;
654 /* Explicitly not marked persistent? */
655 if (!udev->persist_enabled)
658 /* No active config? */
659 actconfig = udev->actconfig;
663 /* FIXME! We should check whether it's open here or not! */
666 * Check that all the interface drivers have a
667 * 'reset_resume' entrypoint
670 for (i = 0; i < actconfig->desc.bNumInterfaces; i++) {
671 struct usb_interface *intf;
672 struct usb_driver *driver;
674 intf = actconfig->interface[i];
675 if (!intf->dev.driver)
677 driver = to_usb_driver(intf->dev.driver);
678 if (!driver->reset_resume)
681 * We have at least one driver, and that one
682 * has a reset_resume method.
689 static void hub_restart(struct usb_hub *hub, int type)
691 struct usb_device *hdev = hub->hdev;
694 /* Check each of the children to see if they require
695 * USB-PERSIST handling or disconnection. Also check
696 * each unoccupied port to make sure it is still disabled.
698 for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
699 struct usb_device *udev = hdev->children[port1-1];
701 u16 portstatus, portchange;
703 if (!udev || udev->state == USB_STATE_NOTATTACHED) {
704 if (type != HUB_RESET) {
705 status = hub_port_status(hub, port1,
706 &portstatus, &portchange);
707 if (status == 0 && (portstatus &
708 USB_PORT_STAT_ENABLE))
709 clear_port_feature(hdev, port1,
710 USB_PORT_FEAT_ENABLE);
715 /* Was the power session lost while we were suspended? */
717 case HUB_RESET_RESUME:
719 portchange = USB_PORT_STAT_C_CONNECTION;
724 status = hub_port_status(hub, port1,
725 &portstatus, &portchange);
729 /* For "USB_PERSIST"-enabled children we must
730 * mark the child device for reset-resume and
731 * turn off the various status changes to prevent
732 * khubd from disconnecting it later.
734 if (status == 0 && !(portstatus & USB_PORT_STAT_ENABLE) &&
735 persistent_device(udev)) {
736 if (portchange & USB_PORT_STAT_C_ENABLE)
737 clear_port_feature(hub->hdev, port1,
738 USB_PORT_FEAT_C_ENABLE);
739 if (portchange & USB_PORT_STAT_C_CONNECTION)
740 clear_port_feature(hub->hdev, port1,
741 USB_PORT_FEAT_C_CONNECTION);
742 udev->reset_resume = 1;
745 /* Otherwise for a reset_resume we must disconnect the child,
746 * but as we may not lock the child device here
747 * we have to do a "logical" disconnect.
749 else if (type == HUB_RESET_RESUME)
750 hub_port_logical_disconnect(hub, port1);
756 #endif /* CONFIG_PM */
758 /* caller has locked the hub device */
759 static int hub_pre_reset(struct usb_interface *intf)
761 struct usb_hub *hub = usb_get_intfdata(intf);
767 /* caller has locked the hub device */
768 static int hub_post_reset(struct usb_interface *intf)
770 struct usb_hub *hub = usb_get_intfdata(intf);
777 static int hub_configure(struct usb_hub *hub,
778 struct usb_endpoint_descriptor *endpoint)
780 struct usb_device *hdev = hub->hdev;
781 struct device *hub_dev = hub->intfdev;
782 u16 hubstatus, hubchange;
783 u16 wHubCharacteristics;
788 hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
791 message = "can't allocate hub irq buffer";
796 hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
798 message = "can't kmalloc hub status buffer";
802 mutex_init(&hub->status_mutex);
804 hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
805 if (!hub->descriptor) {
806 message = "can't kmalloc hub descriptor";
811 /* Request the entire hub descriptor.
812 * hub->descriptor can handle USB_MAXCHILDREN ports,
813 * but the hub can/will return fewer bytes here.
815 ret = get_hub_descriptor(hdev, hub->descriptor,
816 sizeof(*hub->descriptor));
818 message = "can't read hub descriptor";
820 } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
821 message = "hub has too many ports!";
826 hdev->maxchild = hub->descriptor->bNbrPorts;
827 dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
828 (hdev->maxchild == 1) ? "" : "s");
830 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
832 if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
834 char portstr [USB_MAXCHILDREN + 1];
836 for (i = 0; i < hdev->maxchild; i++)
837 portstr[i] = hub->descriptor->DeviceRemovable
838 [((i + 1) / 8)] & (1 << ((i + 1) % 8))
840 portstr[hdev->maxchild] = 0;
841 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
843 dev_dbg(hub_dev, "standalone hub\n");
845 switch (wHubCharacteristics & HUB_CHAR_LPSM) {
847 dev_dbg(hub_dev, "ganged power switching\n");
850 dev_dbg(hub_dev, "individual port power switching\n");
854 dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
858 switch (wHubCharacteristics & HUB_CHAR_OCPM) {
860 dev_dbg(hub_dev, "global over-current protection\n");
863 dev_dbg(hub_dev, "individual port over-current protection\n");
867 dev_dbg(hub_dev, "no over-current protection\n");
871 spin_lock_init (&hub->tt.lock);
872 INIT_LIST_HEAD (&hub->tt.clear_list);
873 INIT_WORK (&hub->tt.kevent, hub_tt_kevent);
874 switch (hdev->descriptor.bDeviceProtocol) {
878 dev_dbg(hub_dev, "Single TT\n");
882 ret = usb_set_interface(hdev, 0, 1);
884 dev_dbg(hub_dev, "TT per port\n");
887 dev_err(hub_dev, "Using single TT (err %d)\n",
892 dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
893 hdev->descriptor.bDeviceProtocol);
897 /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
898 switch (wHubCharacteristics & HUB_CHAR_TTTT) {
899 case HUB_TTTT_8_BITS:
900 if (hdev->descriptor.bDeviceProtocol != 0) {
901 hub->tt.think_time = 666;
902 dev_dbg(hub_dev, "TT requires at most %d "
903 "FS bit times (%d ns)\n",
904 8, hub->tt.think_time);
907 case HUB_TTTT_16_BITS:
908 hub->tt.think_time = 666 * 2;
909 dev_dbg(hub_dev, "TT requires at most %d "
910 "FS bit times (%d ns)\n",
911 16, hub->tt.think_time);
913 case HUB_TTTT_24_BITS:
914 hub->tt.think_time = 666 * 3;
915 dev_dbg(hub_dev, "TT requires at most %d "
916 "FS bit times (%d ns)\n",
917 24, hub->tt.think_time);
919 case HUB_TTTT_32_BITS:
920 hub->tt.think_time = 666 * 4;
921 dev_dbg(hub_dev, "TT requires at most %d "
922 "FS bit times (%d ns)\n",
923 32, hub->tt.think_time);
927 /* probe() zeroes hub->indicator[] */
928 if (wHubCharacteristics & HUB_CHAR_PORTIND) {
929 hub->has_indicators = 1;
930 dev_dbg(hub_dev, "Port indicators are supported\n");
933 dev_dbg(hub_dev, "power on to power good time: %dms\n",
934 hub->descriptor->bPwrOn2PwrGood * 2);
936 /* power budgeting mostly matters with bus-powered hubs,
937 * and battery-powered root hubs (may provide just 8 mA).
939 ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
941 message = "can't get hub status";
944 le16_to_cpus(&hubstatus);
945 if (hdev == hdev->bus->root_hub) {
946 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
947 hub->mA_per_port = 500;
949 hub->mA_per_port = hdev->bus_mA;
950 hub->limited_power = 1;
952 } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
953 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
954 hub->descriptor->bHubContrCurrent);
955 hub->limited_power = 1;
956 if (hdev->maxchild > 0) {
957 int remaining = hdev->bus_mA -
958 hub->descriptor->bHubContrCurrent;
960 if (remaining < hdev->maxchild * 100)
962 "insufficient power available "
963 "to use all downstream ports\n");
964 hub->mA_per_port = 100; /* 7.2.1.1 */
966 } else { /* Self-powered external hub */
967 /* FIXME: What about battery-powered external hubs that
968 * provide less current per port? */
969 hub->mA_per_port = 500;
971 if (hub->mA_per_port < 500)
972 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
975 ret = hub_hub_status(hub, &hubstatus, &hubchange);
977 message = "can't get hub status";
981 /* local power status reports aren't always correct */
982 if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
983 dev_dbg(hub_dev, "local power source is %s\n",
984 (hubstatus & HUB_STATUS_LOCAL_POWER)
985 ? "lost (inactive)" : "good");
987 if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
988 dev_dbg(hub_dev, "%sover-current condition exists\n",
989 (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
991 /* set up the interrupt endpoint
992 * We use the EP's maxpacket size instead of (PORTS+1+7)/8
993 * bytes as USB2.0[11.12.3] says because some hubs are known
994 * to send more data (and thus cause overflow). For root hubs,
995 * maxpktsize is defined in hcd.c's fake endpoint descriptors
996 * to be big enough for at least USB_MAXCHILDREN ports. */
997 pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
998 maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
1000 if (maxp > sizeof(*hub->buffer))
1001 maxp = sizeof(*hub->buffer);
1003 hub->urb = usb_alloc_urb(0, GFP_KERNEL);
1005 message = "couldn't allocate interrupt urb";
1010 usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1011 hub, endpoint->bInterval);
1012 hub->urb->transfer_dma = hub->buffer_dma;
1013 hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1015 /* maybe cycle the hub leds */
1016 if (hub->has_indicators && blinkenlights)
1017 hub->indicator [0] = INDICATOR_CYCLE;
1024 dev_err (hub_dev, "config failed, %s (err %d)\n",
1026 /* hub_disconnect() frees urb and descriptor */
1030 static void hub_release(struct kref *kref)
1032 struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1034 usb_put_intf(to_usb_interface(hub->intfdev));
1038 static unsigned highspeed_hubs;
1040 static void hub_disconnect(struct usb_interface *intf)
1042 struct usb_hub *hub = usb_get_intfdata (intf);
1044 /* Take the hub off the event list and don't let it be added again */
1045 spin_lock_irq(&hub_event_lock);
1046 list_del_init(&hub->event_list);
1047 hub->disconnected = 1;
1048 spin_unlock_irq(&hub_event_lock);
1050 /* Disconnect all children and quiesce the hub */
1054 usb_set_intfdata (intf, NULL);
1056 if (hub->hdev->speed == USB_SPEED_HIGH)
1059 usb_free_urb(hub->urb);
1060 kfree(hub->descriptor);
1062 usb_buffer_free(hub->hdev, sizeof(*hub->buffer), hub->buffer,
1065 kref_put(&hub->kref, hub_release);
1068 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1070 struct usb_host_interface *desc;
1071 struct usb_endpoint_descriptor *endpoint;
1072 struct usb_device *hdev;
1073 struct usb_hub *hub;
1075 desc = intf->cur_altsetting;
1076 hdev = interface_to_usbdev(intf);
1078 #ifdef CONFIG_USB_OTG_BLACKLIST_HUB
1080 dev_warn(&intf->dev, "ignoring external hub\n");
1085 /* Some hubs have a subclass of 1, which AFAICT according to the */
1086 /* specs is not defined, but it works */
1087 if ((desc->desc.bInterfaceSubClass != 0) &&
1088 (desc->desc.bInterfaceSubClass != 1)) {
1090 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
1094 /* Multiple endpoints? What kind of mutant ninja-hub is this? */
1095 if (desc->desc.bNumEndpoints != 1)
1096 goto descriptor_error;
1098 endpoint = &desc->endpoint[0].desc;
1100 /* If it's not an interrupt in endpoint, we'd better punt! */
1101 if (!usb_endpoint_is_int_in(endpoint))
1102 goto descriptor_error;
1104 /* We found a hub */
1105 dev_info (&intf->dev, "USB hub found\n");
1107 hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1109 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
1113 kref_init(&hub->kref);
1114 INIT_LIST_HEAD(&hub->event_list);
1115 hub->intfdev = &intf->dev;
1117 INIT_DELAYED_WORK(&hub->leds, led_work);
1120 usb_set_intfdata (intf, hub);
1121 intf->needs_remote_wakeup = 1;
1123 if (hdev->speed == USB_SPEED_HIGH)
1126 if (hub_configure(hub, endpoint) >= 0)
1129 hub_disconnect (intf);
1134 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1136 struct usb_device *hdev = interface_to_usbdev (intf);
1138 /* assert ifno == 0 (part of hub spec) */
1140 case USBDEVFS_HUB_PORTINFO: {
1141 struct usbdevfs_hub_portinfo *info = user_data;
1144 spin_lock_irq(&device_state_lock);
1145 if (hdev->devnum <= 0)
1148 info->nports = hdev->maxchild;
1149 for (i = 0; i < info->nports; i++) {
1150 if (hdev->children[i] == NULL)
1154 hdev->children[i]->devnum;
1157 spin_unlock_irq(&device_state_lock);
1159 return info->nports + 1;
1168 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1172 for (i = 0; i < udev->maxchild; ++i) {
1173 if (udev->children[i])
1174 recursively_mark_NOTATTACHED(udev->children[i]);
1176 if (udev->state == USB_STATE_SUSPENDED) {
1177 udev->discon_suspended = 1;
1178 udev->active_duration -= jiffies;
1180 udev->state = USB_STATE_NOTATTACHED;
1184 * usb_set_device_state - change a device's current state (usbcore, hcds)
1185 * @udev: pointer to device whose state should be changed
1186 * @new_state: new state value to be stored
1188 * udev->state is _not_ fully protected by the device lock. Although
1189 * most transitions are made only while holding the lock, the state can
1190 * can change to USB_STATE_NOTATTACHED at almost any time. This
1191 * is so that devices can be marked as disconnected as soon as possible,
1192 * without having to wait for any semaphores to be released. As a result,
1193 * all changes to any device's state must be protected by the
1194 * device_state_lock spinlock.
1196 * Once a device has been added to the device tree, all changes to its state
1197 * should be made using this routine. The state should _not_ be set directly.
1199 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1200 * Otherwise udev->state is set to new_state, and if new_state is
1201 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1202 * to USB_STATE_NOTATTACHED.
1204 void usb_set_device_state(struct usb_device *udev,
1205 enum usb_device_state new_state)
1207 unsigned long flags;
1209 spin_lock_irqsave(&device_state_lock, flags);
1210 if (udev->state == USB_STATE_NOTATTACHED)
1212 else if (new_state != USB_STATE_NOTATTACHED) {
1214 /* root hub wakeup capabilities are managed out-of-band
1215 * and may involve silicon errata ... ignore them here.
1218 if (udev->state == USB_STATE_SUSPENDED
1219 || new_state == USB_STATE_SUSPENDED)
1220 ; /* No change to wakeup settings */
1221 else if (new_state == USB_STATE_CONFIGURED)
1222 device_init_wakeup(&udev->dev,
1223 (udev->actconfig->desc.bmAttributes
1224 & USB_CONFIG_ATT_WAKEUP));
1226 device_init_wakeup(&udev->dev, 0);
1228 if (udev->state == USB_STATE_SUSPENDED &&
1229 new_state != USB_STATE_SUSPENDED)
1230 udev->active_duration -= jiffies;
1231 else if (new_state == USB_STATE_SUSPENDED &&
1232 udev->state != USB_STATE_SUSPENDED)
1233 udev->active_duration += jiffies;
1234 udev->state = new_state;
1236 recursively_mark_NOTATTACHED(udev);
1237 spin_unlock_irqrestore(&device_state_lock, flags);
1241 * WUSB devices are simple: they have no hubs behind, so the mapping
1242 * device <-> virtual port number becomes 1:1. Why? to simplify the
1243 * life of the device connection logic in
1244 * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
1245 * handshake we need to assign a temporary address in the unauthorized
1246 * space. For simplicity we use the first virtual port number found to
1247 * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
1248 * and that becomes it's address [X < 128] or its unauthorized address
1251 * We add 1 as an offset to the one-based USB-stack port number
1252 * (zero-based wusb virtual port index) for two reasons: (a) dev addr
1253 * 0 is reserved by USB for default address; (b) Linux's USB stack
1254 * uses always #1 for the root hub of the controller. So USB stack's
1255 * port #1, which is wusb virtual-port #0 has address #2.
1257 static void choose_address(struct usb_device *udev)
1260 struct usb_bus *bus = udev->bus;
1262 /* If khubd ever becomes multithreaded, this will need a lock */
1264 devnum = udev->portnum + 1;
1265 BUG_ON(test_bit(devnum, bus->devmap.devicemap));
1267 /* Try to allocate the next devnum beginning at
1268 * bus->devnum_next. */
1269 devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1272 devnum = find_next_zero_bit(bus->devmap.devicemap,
1274 bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1277 set_bit(devnum, bus->devmap.devicemap);
1278 udev->devnum = devnum;
1282 static void release_address(struct usb_device *udev)
1284 if (udev->devnum > 0) {
1285 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1290 static void update_address(struct usb_device *udev, int devnum)
1292 /* The address for a WUSB device is managed by wusbcore. */
1294 udev->devnum = devnum;
1297 #ifdef CONFIG_USB_SUSPEND
1299 static void usb_stop_pm(struct usb_device *udev)
1301 /* Synchronize with the ksuspend thread to prevent any more
1302 * autosuspend requests from being submitted, and decrement
1303 * the parent's count of unsuspended children.
1306 if (udev->parent && !udev->discon_suspended)
1307 usb_autosuspend_device(udev->parent);
1308 usb_pm_unlock(udev);
1310 /* Stop any autosuspend requests already submitted */
1311 cancel_rearming_delayed_work(&udev->autosuspend);
1316 static inline void usb_stop_pm(struct usb_device *udev)
1322 * usb_disconnect - disconnect a device (usbcore-internal)
1323 * @pdev: pointer to device being disconnected
1324 * Context: !in_interrupt ()
1326 * Something got disconnected. Get rid of it and all of its children.
1328 * If *pdev is a normal device then the parent hub must already be locked.
1329 * If *pdev is a root hub then this routine will acquire the
1330 * usb_bus_list_lock on behalf of the caller.
1332 * Only hub drivers (including virtual root hub drivers for host
1333 * controllers) should ever call this.
1335 * This call is synchronous, and may not be used in an interrupt context.
1337 void usb_disconnect(struct usb_device **pdev)
1339 struct usb_device *udev = *pdev;
1343 pr_debug ("%s nodev\n", __func__);
1347 /* mark the device as inactive, so any further urb submissions for
1348 * this device (and any of its children) will fail immediately.
1349 * this quiesces everyting except pending urbs.
1351 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1352 dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1354 usb_lock_device(udev);
1356 /* Free up all the children before we remove this device */
1357 for (i = 0; i < USB_MAXCHILDREN; i++) {
1358 if (udev->children[i])
1359 usb_disconnect(&udev->children[i]);
1362 /* deallocate hcd/hardware state ... nuking all pending urbs and
1363 * cleaning up all state associated with the current configuration
1364 * so that the hardware is now fully quiesced.
1366 dev_dbg (&udev->dev, "unregistering device\n");
1367 usb_disable_device(udev, 0);
1369 usb_unlock_device(udev);
1371 /* Remove the device-specific files from sysfs. This must be
1372 * done with udev unlocked, because some of the attribute
1373 * routines try to acquire the device lock.
1375 usb_remove_sysfs_dev_files(udev);
1377 /* Unregister the device. The device driver is responsible
1378 * for removing the device files from usbfs and sysfs and for
1379 * de-configuring the device.
1381 device_del(&udev->dev);
1383 /* Free the device number and delete the parent's children[]
1384 * (or root_hub) pointer.
1386 release_address(udev);
1388 /* Avoid races with recursively_mark_NOTATTACHED() */
1389 spin_lock_irq(&device_state_lock);
1391 spin_unlock_irq(&device_state_lock);
1395 put_device(&udev->dev);
1398 #ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
1399 static void show_string(struct usb_device *udev, char *id, char *string)
1403 dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1406 static void announce_device(struct usb_device *udev)
1408 dev_info(&udev->dev, "New USB device found, idVendor=%04x, idProduct=%04x\n",
1409 le16_to_cpu(udev->descriptor.idVendor),
1410 le16_to_cpu(udev->descriptor.idProduct));
1411 dev_info(&udev->dev, "New USB device strings: Mfr=%d, Product=%d, "
1412 "SerialNumber=%d\n",
1413 udev->descriptor.iManufacturer,
1414 udev->descriptor.iProduct,
1415 udev->descriptor.iSerialNumber);
1416 show_string(udev, "Product", udev->product);
1417 show_string(udev, "Manufacturer", udev->manufacturer);
1418 show_string(udev, "SerialNumber", udev->serial);
1421 static inline void announce_device(struct usb_device *udev) { }
1424 #ifdef CONFIG_USB_OTG
1425 #include "otg_whitelist.h"
1429 * usb_configure_device_otg - FIXME (usbcore-internal)
1430 * @udev: newly addressed device (in ADDRESS state)
1432 * Do configuration for On-The-Go devices
1434 static int usb_configure_device_otg(struct usb_device *udev)
1438 #ifdef CONFIG_USB_OTG
1440 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1441 * to wake us after we've powered off VBUS; and HNP, switching roles
1442 * "host" to "peripheral". The OTG descriptor helps figure this out.
1444 if (!udev->bus->is_b_host
1446 && udev->parent == udev->bus->root_hub) {
1447 struct usb_otg_descriptor *desc = 0;
1448 struct usb_bus *bus = udev->bus;
1450 /* descriptor may appear anywhere in config */
1451 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1452 le16_to_cpu(udev->config[0].desc.wTotalLength),
1453 USB_DT_OTG, (void **) &desc) == 0) {
1454 if (desc->bmAttributes & USB_OTG_HNP) {
1455 unsigned port1 = udev->portnum;
1457 dev_info(&udev->dev,
1458 "Dual-Role OTG device on %sHNP port\n",
1459 (port1 == bus->otg_port)
1462 /* enable HNP before suspend, it's simpler */
1463 if (port1 == bus->otg_port)
1464 bus->b_hnp_enable = 1;
1465 err = usb_control_msg(udev,
1466 usb_sndctrlpipe(udev, 0),
1467 USB_REQ_SET_FEATURE, 0,
1469 ? USB_DEVICE_B_HNP_ENABLE
1470 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1471 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1473 /* OTG MESSAGE: report errors here,
1474 * customize to match your product.
1476 dev_info(&udev->dev,
1477 "can't set HNP mode; %d\n",
1479 bus->b_hnp_enable = 0;
1485 if (!is_targeted(udev)) {
1487 /* Maybe it can talk to us, though we can't talk to it.
1488 * (Includes HNP test device.)
1490 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1491 err = usb_port_suspend(udev);
1493 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1505 * usb_configure_device - Detect and probe device intfs/otg (usbcore-internal)
1506 * @udev: newly addressed device (in ADDRESS state)
1508 * This is only called by usb_new_device() and usb_authorize_device()
1509 * and FIXME -- all comments that apply to them apply here wrt to
1512 * If the device is WUSB and not authorized, we don't attempt to read
1513 * the string descriptors, as they will be errored out by the device
1514 * until it has been authorized.
1516 static int usb_configure_device(struct usb_device *udev)
1520 if (udev->config == NULL) {
1521 err = usb_get_configuration(udev);
1523 dev_err(&udev->dev, "can't read configurations, error %d\n",
1528 if (udev->wusb == 1 && udev->authorized == 0) {
1529 udev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1530 udev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1531 udev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1534 /* read the standard strings and cache them if present */
1535 udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1536 udev->manufacturer = usb_cache_string(udev,
1537 udev->descriptor.iManufacturer);
1538 udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1540 err = usb_configure_device_otg(udev);
1547 * usb_new_device - perform initial device setup (usbcore-internal)
1548 * @udev: newly addressed device (in ADDRESS state)
1550 * This is called with devices which have been enumerated, but not yet
1551 * configured. The device descriptor is available, but not descriptors
1552 * for any device configuration. The caller must have locked either
1553 * the parent hub (if udev is a normal device) or else the
1554 * usb_bus_list_lock (if udev is a root hub). The parent's pointer to
1555 * udev has already been installed, but udev is not yet visible through
1556 * sysfs or other filesystem code.
1558 * It will return if the device is configured properly or not. Zero if
1559 * the interface was registered with the driver core; else a negative
1562 * This call is synchronous, and may not be used in an interrupt context.
1564 * Only the hub driver or root-hub registrar should ever call this.
1566 int usb_new_device(struct usb_device *udev)
1570 usb_detect_quirks(udev); /* Determine quirks */
1571 err = usb_configure_device(udev); /* detect & probe dev/intfs */
1574 /* export the usbdev device-node for libusb */
1575 udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
1576 (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
1578 /* Increment the parent's count of unsuspended children */
1580 usb_autoresume_device(udev->parent);
1582 /* Register the device. The device driver is responsible
1583 * for adding the device files to sysfs and for configuring
1586 err = device_add(&udev->dev);
1588 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1592 /* put device-specific files into sysfs */
1593 usb_create_sysfs_dev_files(udev);
1595 /* Tell the world! */
1596 announce_device(udev);
1600 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1606 * usb_deauthorize_device - deauthorize a device (usbcore-internal)
1607 * @usb_dev: USB device
1609 * Move the USB device to a very basic state where interfaces are disabled
1610 * and the device is in fact unconfigured and unusable.
1612 * We share a lock (that we have) with device_del(), so we need to
1615 int usb_deauthorize_device(struct usb_device *usb_dev)
1618 usb_lock_device(usb_dev);
1619 if (usb_dev->authorized == 0)
1620 goto out_unauthorized;
1621 usb_dev->authorized = 0;
1622 usb_set_configuration(usb_dev, -1);
1623 usb_dev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1624 usb_dev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1625 usb_dev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1626 kfree(usb_dev->config);
1627 usb_dev->config = NULL;
1628 for (cnt = 0; cnt < usb_dev->descriptor.bNumConfigurations; cnt++)
1629 kfree(usb_dev->rawdescriptors[cnt]);
1630 usb_dev->descriptor.bNumConfigurations = 0;
1631 kfree(usb_dev->rawdescriptors);
1633 usb_unlock_device(usb_dev);
1638 int usb_authorize_device(struct usb_device *usb_dev)
1641 usb_lock_device(usb_dev);
1642 if (usb_dev->authorized == 1)
1643 goto out_authorized;
1644 kfree(usb_dev->product);
1645 usb_dev->product = NULL;
1646 kfree(usb_dev->manufacturer);
1647 usb_dev->manufacturer = NULL;
1648 kfree(usb_dev->serial);
1649 usb_dev->serial = NULL;
1650 result = usb_autoresume_device(usb_dev);
1652 dev_err(&usb_dev->dev,
1653 "can't autoresume for authorization: %d\n", result);
1654 goto error_autoresume;
1656 result = usb_get_device_descriptor(usb_dev, sizeof(usb_dev->descriptor));
1658 dev_err(&usb_dev->dev, "can't re-read device descriptor for "
1659 "authorization: %d\n", result);
1660 goto error_device_descriptor;
1662 usb_dev->authorized = 1;
1663 result = usb_configure_device(usb_dev);
1665 goto error_configure;
1666 /* Choose and set the configuration. This registers the interfaces
1667 * with the driver core and lets interface drivers bind to them.
1669 c = usb_choose_configuration(usb_dev);
1671 result = usb_set_configuration(usb_dev, c);
1673 dev_err(&usb_dev->dev,
1674 "can't set config #%d, error %d\n", c, result);
1675 /* This need not be fatal. The user can try to
1676 * set other configurations. */
1679 dev_info(&usb_dev->dev, "authorized to connect\n");
1681 error_device_descriptor:
1684 usb_unlock_device(usb_dev); // complements locktree
1689 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
1690 static unsigned hub_is_wusb(struct usb_hub *hub)
1692 struct usb_hcd *hcd;
1693 if (hub->hdev->parent != NULL) /* not a root hub? */
1695 hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
1696 return hcd->wireless;
1700 #define PORT_RESET_TRIES 5
1701 #define SET_ADDRESS_TRIES 2
1702 #define GET_DESCRIPTOR_TRIES 2
1703 #define SET_CONFIG_TRIES (2 * (use_both_schemes + 1))
1704 #define USE_NEW_SCHEME(i) ((i) / 2 == old_scheme_first)
1706 #define HUB_ROOT_RESET_TIME 50 /* times are in msec */
1707 #define HUB_SHORT_RESET_TIME 10
1708 #define HUB_LONG_RESET_TIME 200
1709 #define HUB_RESET_TIMEOUT 500
1711 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1712 struct usb_device *udev, unsigned int delay)
1714 int delay_time, ret;
1718 for (delay_time = 0;
1719 delay_time < HUB_RESET_TIMEOUT;
1720 delay_time += delay) {
1721 /* wait to give the device a chance to reset */
1724 /* read and decode port status */
1725 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1729 /* Device went away? */
1730 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1733 /* bomb out completely if the connection bounced */
1734 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1737 /* if we`ve finished resetting, then break out of the loop */
1738 if (!(portstatus & USB_PORT_STAT_RESET) &&
1739 (portstatus & USB_PORT_STAT_ENABLE)) {
1740 if (hub_is_wusb(hub))
1741 udev->speed = USB_SPEED_VARIABLE;
1742 else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1743 udev->speed = USB_SPEED_HIGH;
1744 else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1745 udev->speed = USB_SPEED_LOW;
1747 udev->speed = USB_SPEED_FULL;
1751 /* switch to the long delay after two short delay failures */
1752 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1753 delay = HUB_LONG_RESET_TIME;
1755 dev_dbg (hub->intfdev,
1756 "port %d not reset yet, waiting %dms\n",
1763 static int hub_port_reset(struct usb_hub *hub, int port1,
1764 struct usb_device *udev, unsigned int delay)
1768 /* Block EHCI CF initialization during the port reset.
1769 * Some companion controllers don't like it when they mix.
1771 down_read(&ehci_cf_port_reset_rwsem);
1773 /* Reset the port */
1774 for (i = 0; i < PORT_RESET_TRIES; i++) {
1775 status = set_port_feature(hub->hdev,
1776 port1, USB_PORT_FEAT_RESET);
1778 dev_err(hub->intfdev,
1779 "cannot reset port %d (err = %d)\n",
1782 status = hub_port_wait_reset(hub, port1, udev, delay);
1783 if (status && status != -ENOTCONN)
1784 dev_dbg(hub->intfdev,
1785 "port_wait_reset: err = %d\n",
1789 /* return on disconnect or reset */
1792 /* TRSTRCY = 10 ms; plus some extra */
1794 update_address(udev, 0);
1798 clear_port_feature(hub->hdev,
1799 port1, USB_PORT_FEAT_C_RESET);
1800 /* FIXME need disconnect() for NOTATTACHED device */
1801 usb_set_device_state(udev, status
1802 ? USB_STATE_NOTATTACHED
1803 : USB_STATE_DEFAULT);
1807 dev_dbg (hub->intfdev,
1808 "port %d not enabled, trying reset again...\n",
1810 delay = HUB_LONG_RESET_TIME;
1813 dev_err (hub->intfdev,
1814 "Cannot enable port %i. Maybe the USB cable is bad?\n",
1818 up_read(&ehci_cf_port_reset_rwsem);
1824 #define MASK_BITS (USB_PORT_STAT_POWER | USB_PORT_STAT_CONNECTION | \
1825 USB_PORT_STAT_SUSPEND)
1826 #define WANT_BITS (USB_PORT_STAT_POWER | USB_PORT_STAT_CONNECTION)
1828 /* Determine whether the device on a port is ready for a normal resume,
1829 * is ready for a reset-resume, or should be disconnected.
1831 static int check_port_resume_type(struct usb_device *udev,
1832 struct usb_hub *hub, int port1,
1833 int status, unsigned portchange, unsigned portstatus)
1835 /* Is the device still present? */
1836 if (status || (portstatus & MASK_BITS) != WANT_BITS) {
1841 /* Can't do a normal resume if the port isn't enabled */
1842 else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume)
1846 dev_dbg(hub->intfdev,
1847 "port %d status %04x.%04x after resume, %d\n",
1848 port1, portchange, portstatus, status);
1849 } else if (udev->reset_resume) {
1851 /* Late port handoff can set status-change bits */
1852 if (portchange & USB_PORT_STAT_C_CONNECTION)
1853 clear_port_feature(hub->hdev, port1,
1854 USB_PORT_FEAT_C_CONNECTION);
1855 if (portchange & USB_PORT_STAT_C_ENABLE)
1856 clear_port_feature(hub->hdev, port1,
1857 USB_PORT_FEAT_C_ENABLE);
1863 #ifdef CONFIG_USB_SUSPEND
1866 * usb_port_suspend - suspend a usb device's upstream port
1867 * @udev: device that's no longer in active use, not a root hub
1868 * Context: must be able to sleep; device not locked; pm locks held
1870 * Suspends a USB device that isn't in active use, conserving power.
1871 * Devices may wake out of a suspend, if anything important happens,
1872 * using the remote wakeup mechanism. They may also be taken out of
1873 * suspend by the host, using usb_port_resume(). It's also routine
1874 * to disconnect devices while they are suspended.
1876 * This only affects the USB hardware for a device; its interfaces
1877 * (and, for hubs, child devices) must already have been suspended.
1879 * Selective port suspend reduces power; most suspended devices draw
1880 * less than 500 uA. It's also used in OTG, along with remote wakeup.
1881 * All devices below the suspended port are also suspended.
1883 * Devices leave suspend state when the host wakes them up. Some devices
1884 * also support "remote wakeup", where the device can activate the USB
1885 * tree above them to deliver data, such as a keypress or packet. In
1886 * some cases, this wakes the USB host.
1888 * Suspending OTG devices may trigger HNP, if that's been enabled
1889 * between a pair of dual-role devices. That will change roles, such
1890 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1892 * Devices on USB hub ports have only one "suspend" state, corresponding
1893 * to ACPI D2, "may cause the device to lose some context".
1894 * State transitions include:
1896 * - suspend, resume ... when the VBUS power link stays live
1897 * - suspend, disconnect ... VBUS lost
1899 * Once VBUS drop breaks the circuit, the port it's using has to go through
1900 * normal re-enumeration procedures, starting with enabling VBUS power.
1901 * Other than re-initializing the hub (plug/unplug, except for root hubs),
1902 * Linux (2.6) currently has NO mechanisms to initiate that: no khubd
1903 * timer, no SRP, no requests through sysfs.
1905 * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1906 * the root hub for their bus goes into global suspend ... so we don't
1907 * (falsely) update the device power state to say it suspended.
1909 * Returns 0 on success, else negative errno.
1911 int usb_port_suspend(struct usb_device *udev)
1913 struct usb_hub *hub = hdev_to_hub(udev->parent);
1914 int port1 = udev->portnum;
1917 // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1919 /* enable remote wakeup when appropriate; this lets the device
1920 * wake up the upstream hub (including maybe the root hub).
1922 * NOTE: OTG devices may issue remote wakeup (or SRP) even when
1923 * we don't explicitly enable it here.
1925 if (udev->do_remote_wakeup) {
1926 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1927 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1928 USB_DEVICE_REMOTE_WAKEUP, 0,
1930 USB_CTRL_SET_TIMEOUT);
1932 dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
1937 status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1939 dev_dbg(hub->intfdev, "can't suspend port %d, status %d\n",
1941 /* paranoia: "should not happen" */
1942 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1943 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1944 USB_DEVICE_REMOTE_WAKEUP, 0,
1946 USB_CTRL_SET_TIMEOUT);
1948 /* device has up to 10 msec to fully suspend */
1949 dev_dbg(&udev->dev, "usb %ssuspend\n",
1950 udev->auto_pm ? "auto-" : "");
1951 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1958 * If the USB "suspend" state is in use (rather than "global suspend"),
1959 * many devices will be individually taken out of suspend state using
1960 * special "resume" signaling. This routine kicks in shortly after
1961 * hardware resume signaling is finished, either because of selective
1962 * resume (by host) or remote wakeup (by device) ... now see what changed
1963 * in the tree that's rooted at this device.
1965 * If @udev->reset_resume is set then the device is reset before the
1966 * status check is done.
1968 static int finish_port_resume(struct usb_device *udev)
1973 /* caller owns the udev device lock */
1974 dev_dbg(&udev->dev, "finish %sresume\n",
1975 udev->reset_resume ? "reset-" : "");
1977 /* usb ch9 identifies four variants of SUSPENDED, based on what
1978 * state the device resumes to. Linux currently won't see the
1979 * first two on the host side; they'd be inside hub_port_init()
1980 * during many timeouts, but khubd can't suspend until later.
1982 usb_set_device_state(udev, udev->actconfig
1983 ? USB_STATE_CONFIGURED
1984 : USB_STATE_ADDRESS);
1986 /* 10.5.4.5 says not to reset a suspended port if the attached
1987 * device is enabled for remote wakeup. Hence the reset
1988 * operation is carried out here, after the port has been
1991 if (udev->reset_resume)
1992 status = usb_reset_device(udev);
1994 /* 10.5.4.5 says be sure devices in the tree are still there.
1995 * For now let's assume the device didn't go crazy on resume,
1996 * and device drivers will know about any resume quirks.
2000 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
2002 status = (status > 0 ? 0 : -ENODEV);
2006 dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
2008 } else if (udev->actconfig) {
2009 le16_to_cpus(&devstatus);
2010 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
2011 status = usb_control_msg(udev,
2012 usb_sndctrlpipe(udev, 0),
2013 USB_REQ_CLEAR_FEATURE,
2015 USB_DEVICE_REMOTE_WAKEUP, 0,
2017 USB_CTRL_SET_TIMEOUT);
2019 dev_dbg(&udev->dev, "disable remote "
2020 "wakeup, status %d\n", status);
2028 * usb_port_resume - re-activate a suspended usb device's upstream port
2029 * @udev: device to re-activate, not a root hub
2030 * Context: must be able to sleep; device not locked; pm locks held
2032 * This will re-activate the suspended device, increasing power usage
2033 * while letting drivers communicate again with its endpoints.
2034 * USB resume explicitly guarantees that the power session between
2035 * the host and the device is the same as it was when the device
2038 * If @udev->reset_resume is set then this routine won't check that the
2039 * port is still enabled. Furthermore, finish_port_resume() above will
2040 * reset @udev. The end result is that a broken power session can be
2041 * recovered and @udev will appear to persist across a loss of VBUS power.
2043 * For example, if a host controller doesn't maintain VBUS suspend current
2044 * during a system sleep or is reset when the system wakes up, all the USB
2045 * power sessions below it will be broken. This is especially troublesome
2046 * for mass-storage devices containing mounted filesystems, since the
2047 * device will appear to have disconnected and all the memory mappings
2048 * to it will be lost. Using the USB_PERSIST facility, the device can be
2049 * made to appear as if it had not disconnected.
2051 * This facility can be dangerous. Although usb_reset_device() makes
2052 * every effort to insure that the same device is present after the
2053 * reset as before, it cannot provide a 100% guarantee. Furthermore it's
2054 * quite possible for a device to remain unaltered but its media to be
2055 * changed. If the user replaces a flash memory card while the system is
2056 * asleep, he will have only himself to blame when the filesystem on the
2057 * new card is corrupted and the system crashes.
2059 * Returns 0 on success, else negative errno.
2061 int usb_port_resume(struct usb_device *udev)
2063 struct usb_hub *hub = hdev_to_hub(udev->parent);
2064 int port1 = udev->portnum;
2066 u16 portchange, portstatus;
2068 /* Skip the initial Clear-Suspend step for a remote wakeup */
2069 status = hub_port_status(hub, port1, &portstatus, &portchange);
2070 if (status == 0 && !(portstatus & USB_PORT_STAT_SUSPEND))
2071 goto SuspendCleared;
2073 // dev_dbg(hub->intfdev, "resume port %d\n", port1);
2075 set_bit(port1, hub->busy_bits);
2077 /* see 7.1.7.7; affects power usage, but not budgeting */
2078 status = clear_port_feature(hub->hdev,
2079 port1, USB_PORT_FEAT_SUSPEND);
2081 dev_dbg(hub->intfdev, "can't resume port %d, status %d\n",
2084 /* drive resume for at least 20 msec */
2085 dev_dbg(&udev->dev, "usb %sresume\n",
2086 udev->auto_pm ? "auto-" : "");
2089 /* Virtual root hubs can trigger on GET_PORT_STATUS to
2090 * stop resume signaling. Then finish the resume
2093 status = hub_port_status(hub, port1, &portstatus, &portchange);
2095 /* TRSMRCY = 10 msec */
2101 if (portchange & USB_PORT_STAT_C_SUSPEND)
2102 clear_port_feature(hub->hdev, port1,
2103 USB_PORT_FEAT_C_SUSPEND);
2106 clear_bit(port1, hub->busy_bits);
2107 if (!hub->hdev->parent && !hub->busy_bits[0])
2108 usb_enable_root_hub_irq(hub->hdev->bus);
2110 status = check_port_resume_type(udev,
2111 hub, port1, status, portchange, portstatus);
2113 status = finish_port_resume(udev);
2115 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2116 hub_port_logical_disconnect(hub, port1);
2121 static int remote_wakeup(struct usb_device *udev)
2125 usb_lock_device(udev);
2126 if (udev->state == USB_STATE_SUSPENDED) {
2127 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
2128 usb_mark_last_busy(udev);
2129 status = usb_external_resume_device(udev);
2131 usb_unlock_device(udev);
2135 #else /* CONFIG_USB_SUSPEND */
2137 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
2139 int usb_port_suspend(struct usb_device *udev)
2144 /* However we may need to do a reset-resume */
2146 int usb_port_resume(struct usb_device *udev)
2148 struct usb_hub *hub = hdev_to_hub(udev->parent);
2149 int port1 = udev->portnum;
2151 u16 portchange, portstatus;
2153 status = hub_port_status(hub, port1, &portstatus, &portchange);
2154 status = check_port_resume_type(udev,
2155 hub, port1, status, portchange, portstatus);
2158 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2159 hub_port_logical_disconnect(hub, port1);
2160 } else if (udev->reset_resume) {
2161 dev_dbg(&udev->dev, "reset-resume\n");
2162 status = usb_reset_device(udev);
2167 static inline int remote_wakeup(struct usb_device *udev)
2174 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
2176 struct usb_hub *hub = usb_get_intfdata (intf);
2177 struct usb_device *hdev = hub->hdev;
2180 /* fail if children aren't already suspended */
2181 for (port1 = 1; port1 <= hdev->maxchild; port1++) {
2182 struct usb_device *udev;
2184 udev = hdev->children [port1-1];
2185 if (udev && udev->can_submit) {
2187 dev_dbg(&intf->dev, "port %d nyet suspended\n",
2193 dev_dbg(&intf->dev, "%s\n", __func__);
2195 /* stop khubd and related activity */
2200 static int hub_resume(struct usb_interface *intf)
2202 struct usb_hub *hub = usb_get_intfdata(intf);
2204 dev_dbg(&intf->dev, "%s\n", __func__);
2205 hub_restart(hub, HUB_RESUME);
2209 static int hub_reset_resume(struct usb_interface *intf)
2211 struct usb_hub *hub = usb_get_intfdata(intf);
2213 dev_dbg(&intf->dev, "%s\n", __func__);
2215 hub_restart(hub, HUB_RESET_RESUME);
2220 * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
2221 * @rhdev: struct usb_device for the root hub
2223 * The USB host controller driver calls this function when its root hub
2224 * is resumed and Vbus power has been interrupted or the controller
2225 * has been reset. The routine marks @rhdev as having lost power.
2226 * When the hub driver is resumed it will take notice and carry out
2227 * power-session recovery for all the "USB-PERSIST"-enabled child devices;
2228 * the others will be disconnected.
2230 void usb_root_hub_lost_power(struct usb_device *rhdev)
2232 dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
2233 rhdev->reset_resume = 1;
2235 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
2237 #else /* CONFIG_PM */
2239 static inline int remote_wakeup(struct usb_device *udev)
2244 #define hub_suspend NULL
2245 #define hub_resume NULL
2246 #define hub_reset_resume NULL
2250 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2252 * Between connect detection and reset signaling there must be a delay
2253 * of 100ms at least for debounce and power-settling. The corresponding
2254 * timer shall restart whenever the downstream port detects a disconnect.
2256 * Apparently there are some bluetooth and irda-dongles and a number of
2257 * low-speed devices for which this debounce period may last over a second.
2258 * Not covered by the spec - but easy to deal with.
2260 * This implementation uses a 1500ms total debounce timeout; if the
2261 * connection isn't stable by then it returns -ETIMEDOUT. It checks
2262 * every 25ms for transient disconnects. When the port status has been
2263 * unchanged for 100ms it returns the port status.
2266 #define HUB_DEBOUNCE_TIMEOUT 1500
2267 #define HUB_DEBOUNCE_STEP 25
2268 #define HUB_DEBOUNCE_STABLE 100
2270 static int hub_port_debounce(struct usb_hub *hub, int port1)
2273 int total_time, stable_time = 0;
2274 u16 portchange, portstatus;
2275 unsigned connection = 0xffff;
2277 for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2278 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2282 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2283 (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2284 stable_time += HUB_DEBOUNCE_STEP;
2285 if (stable_time >= HUB_DEBOUNCE_STABLE)
2289 connection = portstatus & USB_PORT_STAT_CONNECTION;
2292 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2293 clear_port_feature(hub->hdev, port1,
2294 USB_PORT_FEAT_C_CONNECTION);
2297 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2299 msleep(HUB_DEBOUNCE_STEP);
2302 dev_dbg (hub->intfdev,
2303 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2304 port1, total_time, stable_time, portstatus);
2306 if (stable_time < HUB_DEBOUNCE_STABLE)
2311 void usb_ep0_reinit(struct usb_device *udev)
2313 usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2314 usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2315 usb_enable_endpoint(udev, &udev->ep0);
2317 EXPORT_SYMBOL_GPL(usb_ep0_reinit);
2319 #define usb_sndaddr0pipe() (PIPE_CONTROL << 30)
2320 #define usb_rcvaddr0pipe() ((PIPE_CONTROL << 30) | USB_DIR_IN)
2322 static int hub_set_address(struct usb_device *udev, int devnum)
2328 if (udev->state == USB_STATE_ADDRESS)
2330 if (udev->state != USB_STATE_DEFAULT)
2332 retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2333 USB_REQ_SET_ADDRESS, 0, devnum, 0,
2334 NULL, 0, USB_CTRL_SET_TIMEOUT);
2336 /* Device now using proper address. */
2337 update_address(udev, devnum);
2338 usb_set_device_state(udev, USB_STATE_ADDRESS);
2339 usb_ep0_reinit(udev);
2344 /* Reset device, (re)assign address, get device descriptor.
2345 * Device connection must be stable, no more debouncing needed.
2346 * Returns device in USB_STATE_ADDRESS, except on error.
2348 * If this is called for an already-existing device (as part of
2349 * usb_reset_device), the caller must own the device lock. For a
2350 * newly detected device that is not accessible through any global
2351 * pointers, it's not necessary to lock the device.
2354 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2357 static DEFINE_MUTEX(usb_address0_mutex);
2359 struct usb_device *hdev = hub->hdev;
2361 unsigned delay = HUB_SHORT_RESET_TIME;
2362 enum usb_device_speed oldspeed = udev->speed;
2364 int devnum = udev->devnum;
2366 /* root hub ports have a slightly longer reset period
2367 * (from USB 2.0 spec, section 7.1.7.5)
2369 if (!hdev->parent) {
2370 delay = HUB_ROOT_RESET_TIME;
2371 if (port1 == hdev->bus->otg_port)
2372 hdev->bus->b_hnp_enable = 0;
2375 /* Some low speed devices have problems with the quick delay, so */
2376 /* be a bit pessimistic with those devices. RHbug #23670 */
2377 if (oldspeed == USB_SPEED_LOW)
2378 delay = HUB_LONG_RESET_TIME;
2380 mutex_lock(&usb_address0_mutex);
2382 /* Reset the device; full speed may morph to high speed */
2383 retval = hub_port_reset(hub, port1, udev, delay);
2384 if (retval < 0) /* error or disconnect */
2386 /* success, speed is known */
2389 if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2390 dev_dbg(&udev->dev, "device reset changed speed!\n");
2393 oldspeed = udev->speed;
2395 /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2396 * it's fixed size except for full speed devices.
2397 * For Wireless USB devices, ep0 max packet is always 512 (tho
2398 * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
2400 switch (udev->speed) {
2401 case USB_SPEED_VARIABLE: /* fixed at 512 */
2402 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(512);
2404 case USB_SPEED_HIGH: /* fixed at 64 */
2405 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2407 case USB_SPEED_FULL: /* 8, 16, 32, or 64 */
2408 /* to determine the ep0 maxpacket size, try to read
2409 * the device descriptor to get bMaxPacketSize0 and
2410 * then correct our initial guess.
2412 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2414 case USB_SPEED_LOW: /* fixed at 8 */
2415 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2422 switch (udev->speed) {
2423 case USB_SPEED_LOW: speed = "low"; break;
2424 case USB_SPEED_FULL: speed = "full"; break;
2425 case USB_SPEED_HIGH: speed = "high"; break;
2426 case USB_SPEED_VARIABLE:
2430 default: speed = "?"; break;
2432 dev_info (&udev->dev,
2433 "%s %s speed %sUSB device using %s and address %d\n",
2434 (udev->config) ? "reset" : "new", speed, type,
2435 udev->bus->controller->driver->name, devnum);
2437 /* Set up TT records, if needed */
2439 udev->tt = hdev->tt;
2440 udev->ttport = hdev->ttport;
2441 } else if (udev->speed != USB_SPEED_HIGH
2442 && hdev->speed == USB_SPEED_HIGH) {
2443 udev->tt = &hub->tt;
2444 udev->ttport = port1;
2447 /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2448 * Because device hardware and firmware is sometimes buggy in
2449 * this area, and this is how Linux has done it for ages.
2450 * Change it cautiously.
2452 * NOTE: If USE_NEW_SCHEME() is true we will start by issuing
2453 * a 64-byte GET_DESCRIPTOR request. This is what Windows does,
2454 * so it may help with some non-standards-compliant devices.
2455 * Otherwise we start with SET_ADDRESS and then try to read the
2456 * first 8 bytes of the device descriptor to get the ep0 maxpacket
2459 for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2460 if (USE_NEW_SCHEME(retry_counter)) {
2461 struct usb_device_descriptor *buf;
2464 #define GET_DESCRIPTOR_BUFSIZE 64
2465 buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2471 /* Retry on all errors; some devices are flakey.
2472 * 255 is for WUSB devices, we actually need to use
2473 * 512 (WUSB1.0[4.8.1]).
2475 for (j = 0; j < 3; ++j) {
2476 buf->bMaxPacketSize0 = 0;
2477 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2478 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2479 USB_DT_DEVICE << 8, 0,
2480 buf, GET_DESCRIPTOR_BUFSIZE,
2481 USB_CTRL_GET_TIMEOUT);
2482 switch (buf->bMaxPacketSize0) {
2483 case 8: case 16: case 32: case 64: case 255:
2484 if (buf->bDescriptorType ==
2498 udev->descriptor.bMaxPacketSize0 =
2499 buf->bMaxPacketSize0;
2502 retval = hub_port_reset(hub, port1, udev, delay);
2503 if (retval < 0) /* error or disconnect */
2505 if (oldspeed != udev->speed) {
2507 "device reset changed speed!\n");
2512 dev_err(&udev->dev, "device descriptor "
2513 "read/%s, error %d\n",
2518 #undef GET_DESCRIPTOR_BUFSIZE
2522 * If device is WUSB, we already assigned an
2523 * unauthorized address in the Connect Ack sequence;
2524 * authorization will assign the final address.
2526 if (udev->wusb == 0) {
2527 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2528 retval = hub_set_address(udev, devnum);
2535 "device not accepting address %d, error %d\n",
2540 /* cope with hardware quirkiness:
2541 * - let SET_ADDRESS settle, some device hardware wants it
2542 * - read ep0 maxpacket even for high and low speed,
2545 if (USE_NEW_SCHEME(retry_counter))
2549 retval = usb_get_device_descriptor(udev, 8);
2551 dev_err(&udev->dev, "device descriptor "
2552 "read/%s, error %d\n",
2564 i = udev->descriptor.bMaxPacketSize0 == 0xff? /* wusb device? */
2565 512 : udev->descriptor.bMaxPacketSize0;
2566 if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2567 if (udev->speed != USB_SPEED_FULL ||
2568 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2569 dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2573 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2574 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2575 usb_ep0_reinit(udev);
2578 retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2579 if (retval < (signed)sizeof(udev->descriptor)) {
2580 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2591 hub_port_disable(hub, port1, 0);
2592 update_address(udev, devnum); /* for disconnect processing */
2594 mutex_unlock(&usb_address0_mutex);
2599 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2601 struct usb_qualifier_descriptor *qual;
2604 qual = kmalloc (sizeof *qual, GFP_KERNEL);
2608 status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2609 qual, sizeof *qual);
2610 if (status == sizeof *qual) {
2611 dev_info(&udev->dev, "not running at top speed; "
2612 "connect to a high speed hub\n");
2613 /* hub LEDs are probably harder to miss than syslog */
2614 if (hub->has_indicators) {
2615 hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2616 schedule_delayed_work (&hub->leds, 0);
2623 hub_power_remaining (struct usb_hub *hub)
2625 struct usb_device *hdev = hub->hdev;
2629 if (!hub->limited_power)
2632 remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
2633 for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
2634 struct usb_device *udev = hdev->children[port1 - 1];
2640 /* Unconfigured devices may not use more than 100mA,
2641 * or 8mA for OTG ports */
2642 if (udev->actconfig)
2643 delta = udev->actconfig->desc.bMaxPower * 2;
2644 else if (port1 != udev->bus->otg_port || hdev->parent)
2648 if (delta > hub->mA_per_port)
2649 dev_warn(&udev->dev, "%dmA is over %umA budget "
2651 delta, hub->mA_per_port, port1);
2654 if (remaining < 0) {
2655 dev_warn(hub->intfdev, "%dmA over power budget!\n",
2662 /* Handle physical or logical connection change events.
2663 * This routine is called when:
2664 * a port connection-change occurs;
2665 * a port enable-change occurs (often caused by EMI);
2666 * usb_reset_device() encounters changed descriptors (as from
2667 * a firmware download)
2668 * caller already locked the hub
2670 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2671 u16 portstatus, u16 portchange)
2673 struct usb_device *hdev = hub->hdev;
2674 struct device *hub_dev = hub->intfdev;
2675 struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
2676 u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2680 "port %d, status %04x, change %04x, %s\n",
2681 port1, portstatus, portchange, portspeed (portstatus));
2683 if (hub->has_indicators) {
2684 set_port_led(hub, port1, HUB_LED_AUTO);
2685 hub->indicator[port1-1] = INDICATOR_AUTO;
2688 /* Disconnect any existing devices under this port */
2689 if (hdev->children[port1-1])
2690 usb_disconnect(&hdev->children[port1-1]);
2691 clear_bit(port1, hub->change_bits);
2693 #ifdef CONFIG_USB_OTG
2694 /* during HNP, don't repeat the debounce */
2695 if (hdev->bus->is_b_host)
2696 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2699 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2700 status = hub_port_debounce(hub, port1);
2702 if (printk_ratelimit())
2703 dev_err (hub_dev, "connect-debounce failed, "
2704 "port %d disabled\n", port1);
2707 portstatus = status;
2710 /* Return now if nothing is connected */
2711 if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2713 /* maybe switch power back on (e.g. root hub was reset) */
2714 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
2715 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2716 set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2718 if (portstatus & USB_PORT_STAT_ENABLE)
2723 for (i = 0; i < SET_CONFIG_TRIES; i++) {
2724 struct usb_device *udev;
2726 /* reallocate for each attempt, since references
2727 * to the previous one can escape in various ways
2729 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2732 "couldn't allocate port %d usb_device\n",
2737 usb_set_device_state(udev, USB_STATE_POWERED);
2738 udev->speed = USB_SPEED_UNKNOWN;
2739 udev->bus_mA = hub->mA_per_port;
2740 udev->level = hdev->level + 1;
2741 udev->wusb = hub_is_wusb(hub);
2743 /* set the address */
2744 choose_address(udev);
2745 if (udev->devnum <= 0) {
2746 status = -ENOTCONN; /* Don't retry */
2750 /* reset and get descriptor */
2751 status = hub_port_init(hub, udev, port1, i);
2755 /* consecutive bus-powered hubs aren't reliable; they can
2756 * violate the voltage drop budget. if the new child has
2757 * a "powered" LED, users should notice we didn't enable it
2758 * (without reading syslog), even without per-port LEDs
2761 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2762 && udev->bus_mA <= 100) {
2765 status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2768 dev_dbg(&udev->dev, "get status %d ?\n", status);
2771 le16_to_cpus(&devstat);
2772 if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2774 "can't connect bus-powered hub "
2776 if (hub->has_indicators) {
2777 hub->indicator[port1-1] =
2778 INDICATOR_AMBER_BLINK;
2779 schedule_delayed_work (&hub->leds, 0);
2781 status = -ENOTCONN; /* Don't retry */
2786 /* check for devices running slower than they could */
2787 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2788 && udev->speed == USB_SPEED_FULL
2789 && highspeed_hubs != 0)
2790 check_highspeed (hub, udev, port1);
2792 /* Store the parent's children[] pointer. At this point
2793 * udev becomes globally accessible, although presumably
2794 * no one will look at it until hdev is unlocked.
2798 /* We mustn't add new devices if the parent hub has
2799 * been disconnected; we would race with the
2800 * recursively_mark_NOTATTACHED() routine.
2802 spin_lock_irq(&device_state_lock);
2803 if (hdev->state == USB_STATE_NOTATTACHED)
2806 hdev->children[port1-1] = udev;
2807 spin_unlock_irq(&device_state_lock);
2809 /* Run it through the hoops (find a driver, etc) */
2811 status = usb_new_device(udev);
2813 spin_lock_irq(&device_state_lock);
2814 hdev->children[port1-1] = NULL;
2815 spin_unlock_irq(&device_state_lock);
2822 status = hub_power_remaining(hub);
2824 dev_dbg(hub_dev, "%dmA power budget left\n", status);
2829 hub_port_disable(hub, port1, 1);
2831 usb_ep0_reinit(udev);
2832 release_address(udev);
2834 if ((status == -ENOTCONN) || (status == -ENOTSUPP))
2837 if (hub->hdev->parent ||
2838 !hcd->driver->port_handed_over ||
2839 !(hcd->driver->port_handed_over)(hcd, port1))
2840 dev_err(hub_dev, "unable to enumerate USB device on port %d\n",
2844 hub_port_disable(hub, port1, 1);
2845 if (hcd->driver->relinquish_port && !hub->hdev->parent)
2846 hcd->driver->relinquish_port(hcd, port1);
2849 static void hub_events(void)
2851 struct list_head *tmp;
2852 struct usb_device *hdev;
2853 struct usb_interface *intf;
2854 struct usb_hub *hub;
2855 struct device *hub_dev;
2864 * We restart the list every time to avoid a deadlock with
2865 * deleting hubs downstream from this one. This should be
2866 * safe since we delete the hub from the event list.
2867 * Not the most efficient, but avoids deadlocks.
2871 /* Grab the first entry at the beginning of the list */
2872 spin_lock_irq(&hub_event_lock);
2873 if (list_empty(&hub_event_list)) {
2874 spin_unlock_irq(&hub_event_lock);
2878 tmp = hub_event_list.next;
2881 hub = list_entry(tmp, struct usb_hub, event_list);
2882 kref_get(&hub->kref);
2883 spin_unlock_irq(&hub_event_lock);
2886 hub_dev = hub->intfdev;
2887 intf = to_usb_interface(hub_dev);
2888 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
2889 hdev->state, hub->descriptor
2890 ? hub->descriptor->bNbrPorts
2892 /* NOTE: expects max 15 ports... */
2893 (u16) hub->change_bits[0],
2894 (u16) hub->event_bits[0]);
2896 /* Lock the device, then check to see if we were
2897 * disconnected while waiting for the lock to succeed. */
2898 usb_lock_device(hdev);
2899 if (unlikely(hub->disconnected))
2902 /* If the hub has died, clean up after it */
2903 if (hdev->state == USB_STATE_NOTATTACHED) {
2904 hub->error = -ENODEV;
2910 ret = usb_autopm_get_interface(intf);
2912 dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
2916 /* If this is an inactive hub, do nothing */
2921 dev_dbg (hub_dev, "resetting for error %d\n",
2924 ret = usb_reset_composite_device(hdev, intf);
2927 "error resetting hub: %d\n", ret);
2935 /* deal with port status changes */
2936 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2937 if (test_bit(i, hub->busy_bits))
2939 connect_change = test_bit(i, hub->change_bits);
2940 if (!test_and_clear_bit(i, hub->event_bits) &&
2941 !connect_change && !hub->activating)
2944 ret = hub_port_status(hub, i,
2945 &portstatus, &portchange);
2949 if (hub->activating && !hdev->children[i-1] &&
2951 USB_PORT_STAT_CONNECTION))
2954 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2955 clear_port_feature(hdev, i,
2956 USB_PORT_FEAT_C_CONNECTION);
2960 if (portchange & USB_PORT_STAT_C_ENABLE) {
2961 if (!connect_change)
2963 "port %d enable change, "
2966 clear_port_feature(hdev, i,
2967 USB_PORT_FEAT_C_ENABLE);
2970 * EM interference sometimes causes badly
2971 * shielded USB devices to be shutdown by
2972 * the hub, this hack enables them again.
2973 * Works at least with mouse driver.
2975 if (!(portstatus & USB_PORT_STAT_ENABLE)
2977 && hdev->children[i-1]) {
2980 "disabled by hub (EMI?), "
2987 if (portchange & USB_PORT_STAT_C_SUSPEND) {
2988 clear_port_feature(hdev, i,
2989 USB_PORT_FEAT_C_SUSPEND);
2990 if (hdev->children[i-1]) {
2991 ret = remote_wakeup(hdev->
2997 hub_port_disable(hub, i, 1);
3000 "resume on port %d, status %d\n",
3004 if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
3006 "over-current change on port %d\n",
3008 clear_port_feature(hdev, i,
3009 USB_PORT_FEAT_C_OVER_CURRENT);
3013 if (portchange & USB_PORT_STAT_C_RESET) {
3015 "reset change on port %d\n",
3017 clear_port_feature(hdev, i,
3018 USB_PORT_FEAT_C_RESET);
3022 hub_port_connect_change(hub, i,
3023 portstatus, portchange);
3026 /* deal with hub status changes */
3027 if (test_and_clear_bit(0, hub->event_bits) == 0)
3029 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
3030 dev_err (hub_dev, "get_hub_status failed\n");
3032 if (hubchange & HUB_CHANGE_LOCAL_POWER) {
3033 dev_dbg (hub_dev, "power change\n");
3034 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
3035 if (hubstatus & HUB_STATUS_LOCAL_POWER)
3036 /* FIXME: Is this always true? */
3037 hub->limited_power = 1;
3039 hub->limited_power = 0;
3041 if (hubchange & HUB_CHANGE_OVERCURRENT) {
3042 dev_dbg (hub_dev, "overcurrent change\n");
3043 msleep(500); /* Cool down */
3044 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
3049 hub->activating = 0;
3051 /* If this is a root hub, tell the HCD it's okay to
3052 * re-enable port-change interrupts now. */
3053 if (!hdev->parent && !hub->busy_bits[0])
3054 usb_enable_root_hub_irq(hdev->bus);
3057 /* Allow autosuspend if we're not going to run again */
3058 if (list_empty(&hub->event_list))
3059 usb_autopm_enable(intf);
3061 usb_unlock_device(hdev);
3062 kref_put(&hub->kref, hub_release);
3064 } /* end while (1) */
3067 static int hub_thread(void *__unused)
3069 /* khubd needs to be freezable to avoid intefering with USB-PERSIST
3070 * port handover. Otherwise it might see that a full-speed device
3071 * was gone before the EHCI controller had handed its port over to
3072 * the companion full-speed controller.
3078 wait_event_freezable(khubd_wait,
3079 !list_empty(&hub_event_list) ||
3080 kthread_should_stop());
3081 } while (!kthread_should_stop() || !list_empty(&hub_event_list));
3083 pr_debug("%s: khubd exiting\n", usbcore_name);
3087 static struct usb_device_id hub_id_table [] = {
3088 { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
3089 .bDeviceClass = USB_CLASS_HUB},
3090 { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
3091 .bInterfaceClass = USB_CLASS_HUB},
3092 { } /* Terminating entry */
3095 MODULE_DEVICE_TABLE (usb, hub_id_table);
3097 static struct usb_driver hub_driver = {
3100 .disconnect = hub_disconnect,
3101 .suspend = hub_suspend,
3102 .resume = hub_resume,
3103 .reset_resume = hub_reset_resume,
3104 .pre_reset = hub_pre_reset,
3105 .post_reset = hub_post_reset,
3107 .id_table = hub_id_table,
3108 .supports_autosuspend = 1,
3111 int usb_hub_init(void)
3113 if (usb_register(&hub_driver) < 0) {
3114 printk(KERN_ERR "%s: can't register hub driver\n",
3119 khubd_task = kthread_run(hub_thread, NULL, "khubd");
3120 if (!IS_ERR(khubd_task))
3123 /* Fall through if kernel_thread failed */
3124 usb_deregister(&hub_driver);
3125 printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
3130 void usb_hub_cleanup(void)
3132 kthread_stop(khubd_task);
3135 * Hub resources are freed for us by usb_deregister. It calls
3136 * usb_driver_purge on every device which in turn calls that
3137 * devices disconnect function if it is using this driver.
3138 * The hub_disconnect function takes care of releasing the
3139 * individual hub resources. -greg
3141 usb_deregister(&hub_driver);
3142 } /* usb_hub_cleanup() */
3144 static int descriptors_changed(struct usb_device *udev,
3145 struct usb_device_descriptor *old_device_descriptor)
3149 unsigned serial_len = 0;
3151 unsigned old_length;
3155 if (memcmp(&udev->descriptor, old_device_descriptor,
3156 sizeof(*old_device_descriptor)) != 0)
3159 /* Since the idVendor, idProduct, and bcdDevice values in the
3160 * device descriptor haven't changed, we will assume the
3161 * Manufacturer and Product strings haven't changed either.
3162 * But the SerialNumber string could be different (e.g., a
3163 * different flash card of the same brand).
3166 serial_len = strlen(udev->serial) + 1;
3169 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
3170 old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
3171 len = max(len, old_length);
3174 buf = kmalloc(len, GFP_NOIO);
3176 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
3177 /* assume the worst */
3180 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
3181 old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
3182 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
3184 if (length != old_length) {
3185 dev_dbg(&udev->dev, "config index %d, error %d\n",
3190 if (memcmp (buf, udev->rawdescriptors[index], old_length)
3192 dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
3194 ((struct usb_config_descriptor *) buf)->
3195 bConfigurationValue);
3201 if (!changed && serial_len) {
3202 length = usb_string(udev, udev->descriptor.iSerialNumber,
3204 if (length + 1 != serial_len) {
3205 dev_dbg(&udev->dev, "serial string error %d\n",
3208 } else if (memcmp(buf, udev->serial, length) != 0) {
3209 dev_dbg(&udev->dev, "serial string changed\n");
3219 * usb_reset_device - perform a USB port reset to reinitialize a device
3220 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
3222 * WARNING - don't use this routine to reset a composite device
3223 * (one with multiple interfaces owned by separate drivers)!
3224 * Use usb_reset_composite_device() instead.
3226 * Do a port reset, reassign the device's address, and establish its
3227 * former operating configuration. If the reset fails, or the device's
3228 * descriptors change from their values before the reset, or the original
3229 * configuration and altsettings cannot be restored, a flag will be set
3230 * telling khubd to pretend the device has been disconnected and then
3231 * re-connected. All drivers will be unbound, and the device will be
3232 * re-enumerated and probed all over again.
3234 * Returns 0 if the reset succeeded, -ENODEV if the device has been
3235 * flagged for logical disconnection, or some other negative error code
3236 * if the reset wasn't even attempted.
3238 * The caller must own the device lock. For example, it's safe to use
3239 * this from a driver probe() routine after downloading new firmware.
3240 * For calls that might not occur during probe(), drivers should lock
3241 * the device using usb_lock_device_for_reset().
3243 * Locking exception: This routine may also be called from within an
3244 * autoresume handler. Such usage won't conflict with other tasks
3245 * holding the device lock because these tasks should always call
3246 * usb_autopm_resume_device(), thereby preventing any unwanted autoresume.
3248 int usb_reset_device(struct usb_device *udev)
3250 struct usb_device *parent_hdev = udev->parent;
3251 struct usb_hub *parent_hub;
3252 struct usb_device_descriptor descriptor = udev->descriptor;
3254 int port1 = udev->portnum;
3256 if (udev->state == USB_STATE_NOTATTACHED ||
3257 udev->state == USB_STATE_SUSPENDED) {
3258 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3264 /* this requires hcd-specific logic; see OHCI hc_restart() */
3265 dev_dbg(&udev->dev, "%s for root hub!\n", __func__);
3268 parent_hub = hdev_to_hub(parent_hdev);
3270 set_bit(port1, parent_hub->busy_bits);
3271 for (i = 0; i < SET_CONFIG_TRIES; ++i) {
3273 /* ep0 maxpacket size may change; let the HCD know about it.
3274 * Other endpoints will be handled by re-enumeration. */
3275 usb_ep0_reinit(udev);
3276 ret = hub_port_init(parent_hub, udev, port1, i);
3277 if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
3280 clear_bit(port1, parent_hub->busy_bits);
3281 if (!parent_hdev->parent && !parent_hub->busy_bits[0])
3282 usb_enable_root_hub_irq(parent_hdev->bus);
3287 /* Device might have changed firmware (DFU or similar) */
3288 if (descriptors_changed(udev, &descriptor)) {
3289 dev_info(&udev->dev, "device firmware changed\n");
3290 udev->descriptor = descriptor; /* for disconnect() calls */
3294 if (!udev->actconfig)
3297 ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3298 USB_REQ_SET_CONFIGURATION, 0,
3299 udev->actconfig->desc.bConfigurationValue, 0,
3300 NULL, 0, USB_CTRL_SET_TIMEOUT);
3303 "can't restore configuration #%d (error=%d)\n",
3304 udev->actconfig->desc.bConfigurationValue, ret);
3307 usb_set_device_state(udev, USB_STATE_CONFIGURED);
3309 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3310 struct usb_interface *intf = udev->actconfig->interface[i];
3311 struct usb_interface_descriptor *desc;
3313 /* set_interface resets host side toggle even
3314 * for altsetting zero. the interface may have no driver.
3316 desc = &intf->cur_altsetting->desc;
3317 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3318 desc->bAlternateSetting);
3320 dev_err(&udev->dev, "failed to restore interface %d "
3321 "altsetting %d (error=%d)\n",
3322 desc->bInterfaceNumber,
3323 desc->bAlternateSetting,
3333 hub_port_logical_disconnect(parent_hub, port1);
3336 EXPORT_SYMBOL_GPL(usb_reset_device);
3339 * usb_reset_composite_device - warn interface drivers and perform a USB port reset
3340 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
3341 * @iface: interface bound to the driver making the request (optional)
3343 * Warns all drivers bound to registered interfaces (using their pre_reset
3344 * method), performs the port reset, and then lets the drivers know that
3345 * the reset is over (using their post_reset method).
3347 * Return value is the same as for usb_reset_device().
3349 * The caller must own the device lock. For example, it's safe to use
3350 * this from a driver probe() routine after downloading new firmware.
3351 * For calls that might not occur during probe(), drivers should lock
3352 * the device using usb_lock_device_for_reset().
3354 int usb_reset_composite_device(struct usb_device *udev,
3355 struct usb_interface *iface)
3359 struct usb_host_config *config = udev->actconfig;
3361 if (udev->state == USB_STATE_NOTATTACHED ||
3362 udev->state == USB_STATE_SUSPENDED) {
3363 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3368 /* Prevent autosuspend during the reset */
3369 usb_autoresume_device(udev);
3371 if (iface && iface->condition != USB_INTERFACE_BINDING)
3375 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
3376 struct usb_interface *cintf = config->interface[i];
3377 struct usb_driver *drv;
3379 if (cintf->dev.driver) {
3380 drv = to_usb_driver(cintf->dev.driver);
3382 (drv->pre_reset)(cintf);
3383 /* FIXME: Unbind if pre_reset returns an error or isn't defined */
3388 ret = usb_reset_device(udev);
3391 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
3392 struct usb_interface *cintf = config->interface[i];
3393 struct usb_driver *drv;
3395 if (cintf->dev.driver) {
3396 drv = to_usb_driver(cintf->dev.driver);
3397 if (drv->post_reset)
3398 (drv->post_reset)(cintf);
3399 /* FIXME: Unbind if post_reset returns an error or isn't defined */
3404 usb_autosuspend_device(udev);
3407 EXPORT_SYMBOL_GPL(usb_reset_composite_device);