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
156 static void hub_release(struct kref *kref);
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,
181 struct usb_hub_descriptor *desc)
186 if (hub_is_superspeed(hdev)) {
187 dtype = USB_DT_SS_HUB;
188 size = USB_DT_SS_HUB_SIZE;
191 size = sizeof(struct usb_hub_descriptor);
194 for (i = 0; i < 3; i++) {
195 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
196 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
197 dtype << 8, 0, desc, size,
198 USB_CTRL_GET_TIMEOUT);
199 if (hub_is_superspeed(hdev)) {
202 } else if (ret >= USB_DT_HUB_NONVAR_SIZE + 2) {
203 /* Make sure we have the DeviceRemovable field. */
204 size = USB_DT_HUB_NONVAR_SIZE + desc->bNbrPorts / 8 + 1;
214 * USB 2.0 spec Section 11.24.2.1
216 static int clear_hub_feature(struct usb_device *hdev, int feature)
218 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
219 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
223 * USB 2.0 spec Section 11.24.2.2
225 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
227 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
228 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
233 * USB 2.0 spec Section 11.24.2.13
235 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
237 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
238 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
243 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
244 * for info about using port indicators
246 static void set_port_led(
252 int status = set_port_feature(hub->hdev, (selector << 8) | port1,
253 USB_PORT_FEAT_INDICATOR);
255 dev_dbg (hub->intfdev,
256 "port %d indicator %s status %d\n",
258 ({ char *s; switch (selector) {
259 case HUB_LED_AMBER: s = "amber"; break;
260 case HUB_LED_GREEN: s = "green"; break;
261 case HUB_LED_OFF: s = "off"; break;
262 case HUB_LED_AUTO: s = "auto"; break;
263 default: s = "??"; break;
268 #define LED_CYCLE_PERIOD ((2*HZ)/3)
270 static void led_work (struct work_struct *work)
272 struct usb_hub *hub =
273 container_of(work, struct usb_hub, leds.work);
274 struct usb_device *hdev = hub->hdev;
276 unsigned changed = 0;
279 if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
282 for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
283 unsigned selector, mode;
285 /* 30%-50% duty cycle */
287 switch (hub->indicator[i]) {
289 case INDICATOR_CYCLE:
291 selector = HUB_LED_AUTO;
292 mode = INDICATOR_AUTO;
294 /* blinking green = sw attention */
295 case INDICATOR_GREEN_BLINK:
296 selector = HUB_LED_GREEN;
297 mode = INDICATOR_GREEN_BLINK_OFF;
299 case INDICATOR_GREEN_BLINK_OFF:
300 selector = HUB_LED_OFF;
301 mode = INDICATOR_GREEN_BLINK;
303 /* blinking amber = hw attention */
304 case INDICATOR_AMBER_BLINK:
305 selector = HUB_LED_AMBER;
306 mode = INDICATOR_AMBER_BLINK_OFF;
308 case INDICATOR_AMBER_BLINK_OFF:
309 selector = HUB_LED_OFF;
310 mode = INDICATOR_AMBER_BLINK;
312 /* blink green/amber = reserved */
313 case INDICATOR_ALT_BLINK:
314 selector = HUB_LED_GREEN;
315 mode = INDICATOR_ALT_BLINK_OFF;
317 case INDICATOR_ALT_BLINK_OFF:
318 selector = HUB_LED_AMBER;
319 mode = INDICATOR_ALT_BLINK;
324 if (selector != HUB_LED_AUTO)
326 set_port_led(hub, i + 1, selector);
327 hub->indicator[i] = mode;
329 if (!changed && blinkenlights) {
331 cursor %= hub->descriptor->bNbrPorts;
332 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
333 hub->indicator[cursor] = INDICATOR_CYCLE;
337 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
340 /* use a short timeout for hub/port status fetches */
341 #define USB_STS_TIMEOUT 1000
342 #define USB_STS_RETRIES 5
345 * USB 2.0 spec Section 11.24.2.6
347 static int get_hub_status(struct usb_device *hdev,
348 struct usb_hub_status *data)
350 int i, status = -ETIMEDOUT;
352 for (i = 0; i < USB_STS_RETRIES &&
353 (status == -ETIMEDOUT || status == -EPIPE); i++) {
354 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
355 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
356 data, sizeof(*data), USB_STS_TIMEOUT);
362 * USB 2.0 spec Section 11.24.2.7
364 static int get_port_status(struct usb_device *hdev, int port1,
365 struct usb_port_status *data)
367 int i, status = -ETIMEDOUT;
369 for (i = 0; i < USB_STS_RETRIES &&
370 (status == -ETIMEDOUT || status == -EPIPE); i++) {
371 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
372 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
373 data, sizeof(*data), USB_STS_TIMEOUT);
378 static int hub_port_status(struct usb_hub *hub, int port1,
379 u16 *status, u16 *change)
383 mutex_lock(&hub->status_mutex);
384 ret = get_port_status(hub->hdev, port1, &hub->status->port);
386 dev_err(hub->intfdev,
387 "%s failed (err = %d)\n", __func__, ret);
391 *status = le16_to_cpu(hub->status->port.wPortStatus);
392 *change = le16_to_cpu(hub->status->port.wPortChange);
396 mutex_unlock(&hub->status_mutex);
400 static void kick_khubd(struct usb_hub *hub)
404 spin_lock_irqsave(&hub_event_lock, flags);
405 if (!hub->disconnected && list_empty(&hub->event_list)) {
406 list_add_tail(&hub->event_list, &hub_event_list);
408 /* Suppress autosuspend until khubd runs */
409 usb_autopm_get_interface_no_resume(
410 to_usb_interface(hub->intfdev));
411 wake_up(&khubd_wait);
413 spin_unlock_irqrestore(&hub_event_lock, flags);
416 void usb_kick_khubd(struct usb_device *hdev)
418 struct usb_hub *hub = hdev_to_hub(hdev);
425 /* completion function, fires on port status changes and various faults */
426 static void hub_irq(struct urb *urb)
428 struct usb_hub *hub = urb->context;
429 int status = urb->status;
434 case -ENOENT: /* synchronous unlink */
435 case -ECONNRESET: /* async unlink */
436 case -ESHUTDOWN: /* hardware going away */
439 default: /* presumably an error */
440 /* Cause a hub reset after 10 consecutive errors */
441 dev_dbg (hub->intfdev, "transfer --> %d\n", status);
442 if ((++hub->nerrors < 10) || hub->error)
447 /* let khubd handle things */
448 case 0: /* we got data: port status changed */
450 for (i = 0; i < urb->actual_length; ++i)
451 bits |= ((unsigned long) ((*hub->buffer)[i]))
453 hub->event_bits[0] = bits;
459 /* Something happened, let khubd figure it out */
466 if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
467 && status != -ENODEV && status != -EPERM)
468 dev_err (hub->intfdev, "resubmit --> %d\n", status);
471 /* USB 2.0 spec Section 11.24.2.3 */
473 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
475 /* Need to clear both directions for control ep */
476 if (((devinfo >> 11) & USB_ENDPOINT_XFERTYPE_MASK) ==
477 USB_ENDPOINT_XFER_CONTROL) {
478 int status = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
479 HUB_CLEAR_TT_BUFFER, USB_RT_PORT,
480 devinfo ^ 0x8000, tt, NULL, 0, 1000);
484 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
485 HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
490 * enumeration blocks khubd for a long time. we use keventd instead, since
491 * long blocking there is the exception, not the rule. accordingly, HCDs
492 * talking to TTs must queue control transfers (not just bulk and iso), so
493 * both can talk to the same hub concurrently.
495 static void hub_tt_work(struct work_struct *work)
497 struct usb_hub *hub =
498 container_of(work, struct usb_hub, tt.clear_work);
502 spin_lock_irqsave (&hub->tt.lock, flags);
503 while (!list_empty(&hub->tt.clear_list)) {
504 struct list_head *next;
505 struct usb_tt_clear *clear;
506 struct usb_device *hdev = hub->hdev;
507 const struct hc_driver *drv;
510 if (!hub->quiescing && --limit < 0)
513 next = hub->tt.clear_list.next;
514 clear = list_entry (next, struct usb_tt_clear, clear_list);
515 list_del (&clear->clear_list);
517 /* drop lock so HCD can concurrently report other TT errors */
518 spin_unlock_irqrestore (&hub->tt.lock, flags);
519 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
522 "clear tt %d (%04x) error %d\n",
523 clear->tt, clear->devinfo, status);
525 /* Tell the HCD, even if the operation failed */
526 drv = clear->hcd->driver;
527 if (drv->clear_tt_buffer_complete)
528 (drv->clear_tt_buffer_complete)(clear->hcd, clear->ep);
531 spin_lock_irqsave(&hub->tt.lock, flags);
533 spin_unlock_irqrestore (&hub->tt.lock, flags);
537 * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
538 * @urb: an URB associated with the failed or incomplete split transaction
540 * High speed HCDs use this to tell the hub driver that some split control or
541 * bulk transaction failed in a way that requires clearing internal state of
542 * a transaction translator. This is normally detected (and reported) from
545 * It may not be possible for that hub to handle additional full (or low)
546 * speed transactions until that state is fully cleared out.
548 int usb_hub_clear_tt_buffer(struct urb *urb)
550 struct usb_device *udev = urb->dev;
551 int pipe = urb->pipe;
552 struct usb_tt *tt = udev->tt;
554 struct usb_tt_clear *clear;
556 /* we've got to cope with an arbitrary number of pending TT clears,
557 * since each TT has "at least two" buffers that can need it (and
558 * there can be many TTs per hub). even if they're uncommon.
560 if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) {
561 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
562 /* FIXME recover somehow ... RESET_TT? */
566 /* info that CLEAR_TT_BUFFER needs */
567 clear->tt = tt->multi ? udev->ttport : 1;
568 clear->devinfo = usb_pipeendpoint (pipe);
569 clear->devinfo |= udev->devnum << 4;
570 clear->devinfo |= usb_pipecontrol (pipe)
571 ? (USB_ENDPOINT_XFER_CONTROL << 11)
572 : (USB_ENDPOINT_XFER_BULK << 11);
573 if (usb_pipein (pipe))
574 clear->devinfo |= 1 << 15;
576 /* info for completion callback */
577 clear->hcd = bus_to_hcd(udev->bus);
580 /* tell keventd to clear state for this TT */
581 spin_lock_irqsave (&tt->lock, flags);
582 list_add_tail (&clear->clear_list, &tt->clear_list);
583 schedule_work(&tt->clear_work);
584 spin_unlock_irqrestore (&tt->lock, flags);
587 EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer);
589 /* If do_delay is false, return the number of milliseconds the caller
592 static unsigned hub_power_on(struct usb_hub *hub, bool do_delay)
595 unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
597 u16 wHubCharacteristics =
598 le16_to_cpu(hub->descriptor->wHubCharacteristics);
600 /* Enable power on each port. Some hubs have reserved values
601 * of LPSM (> 2) in their descriptors, even though they are
602 * USB 2.0 hubs. Some hubs do not implement port-power switching
603 * but only emulate it. In all cases, the ports won't work
604 * unless we send these messages to the hub.
606 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
607 dev_dbg(hub->intfdev, "enabling power on all ports\n");
609 dev_dbg(hub->intfdev, "trying to enable port power on "
610 "non-switchable hub\n");
611 for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
612 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
614 /* Wait at least 100 msec for power to become stable */
615 delay = max(pgood_delay, (unsigned) 100);
621 static int hub_hub_status(struct usb_hub *hub,
622 u16 *status, u16 *change)
626 mutex_lock(&hub->status_mutex);
627 ret = get_hub_status(hub->hdev, &hub->status->hub);
629 dev_err (hub->intfdev,
630 "%s failed (err = %d)\n", __func__, ret);
632 *status = le16_to_cpu(hub->status->hub.wHubStatus);
633 *change = le16_to_cpu(hub->status->hub.wHubChange);
636 mutex_unlock(&hub->status_mutex);
640 static int hub_set_port_link_state(struct usb_hub *hub, int port1,
641 unsigned int link_status)
643 return set_port_feature(hub->hdev,
644 port1 | (link_status << 3),
645 USB_PORT_FEAT_LINK_STATE);
649 * If USB 3.0 ports are placed into the Disabled state, they will no longer
650 * detect any device connects or disconnects. This is generally not what the
651 * USB core wants, since it expects a disabled port to produce a port status
652 * change event when a new device connects.
654 * Instead, set the link state to Disabled, wait for the link to settle into
655 * that state, clear any change bits, and then put the port into the RxDetect
658 static int hub_usb3_port_disable(struct usb_hub *hub, int port1)
662 u16 portchange, portstatus;
664 if (!hub_is_superspeed(hub->hdev))
667 ret = hub_port_status(hub, port1, &portstatus, &portchange);
672 * USB controller Advanced Micro Devices, Inc. [AMD] FCH USB XHCI
673 * Controller [1022:7814] will have spurious result making the following
674 * usb 3.0 device hotplugging route to the 2.0 root hub and recognized
675 * as high-speed device if we set the usb 3.0 port link state to
676 * Disabled. Since it's already in USB_SS_PORT_LS_RX_DETECT state, we
677 * check the state here to avoid the bug.
679 if ((portstatus & USB_PORT_STAT_LINK_STATE) ==
680 USB_SS_PORT_LS_RX_DETECT) {
681 dev_dbg(hub->intfdev,
682 "Not disabling port %d; link state is RxDetect\n",
687 ret = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_SS_DISABLED);
689 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
694 /* Wait for the link to enter the disabled state. */
695 for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
696 ret = hub_port_status(hub, port1, &portstatus, &portchange);
700 if ((portstatus & USB_PORT_STAT_LINK_STATE) ==
701 USB_SS_PORT_LS_SS_DISABLED)
703 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
705 msleep(HUB_DEBOUNCE_STEP);
707 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
708 dev_warn(hub->intfdev, "Could not disable port %d after %d ms\n",
711 return hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_RX_DETECT);
714 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
716 struct usb_device *hdev = hub->hdev;
719 if (hdev->children[port1-1] && set_state)
720 usb_set_device_state(hdev->children[port1-1],
721 USB_STATE_NOTATTACHED);
723 if (hub_is_superspeed(hub->hdev))
724 ret = hub_usb3_port_disable(hub, port1);
726 ret = clear_port_feature(hdev, port1,
727 USB_PORT_FEAT_ENABLE);
730 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
736 * Disable a port and mark a logical connect-change event, so that some
737 * time later khubd will disconnect() any existing usb_device on the port
738 * and will re-enumerate if there actually is a device attached.
740 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
742 dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
743 hub_port_disable(hub, port1, 1);
745 /* FIXME let caller ask to power down the port:
746 * - some devices won't enumerate without a VBUS power cycle
747 * - SRP saves power that way
748 * - ... new call, TBD ...
749 * That's easy if this hub can switch power per-port, and
750 * khubd reactivates the port later (timer, SRP, etc).
751 * Powerdown must be optional, because of reset/DFU.
754 set_bit(port1, hub->change_bits);
759 * usb_remove_device - disable a device's port on its parent hub
760 * @udev: device to be disabled and removed
761 * Context: @udev locked, must be able to sleep.
763 * After @udev's port has been disabled, khubd is notified and it will
764 * see that the device has been disconnected. When the device is
765 * physically unplugged and something is plugged in, the events will
766 * be received and processed normally.
768 int usb_remove_device(struct usb_device *udev)
771 struct usb_interface *intf;
773 if (!udev->parent) /* Can't remove a root hub */
775 hub = hdev_to_hub(udev->parent);
776 intf = to_usb_interface(hub->intfdev);
778 usb_autopm_get_interface(intf);
779 set_bit(udev->portnum, hub->removed_bits);
780 hub_port_logical_disconnect(hub, udev->portnum);
781 usb_autopm_put_interface(intf);
785 enum hub_activation_type {
786 HUB_INIT, HUB_INIT2, HUB_INIT3, /* INITs must come first */
787 HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
790 static void hub_init_func2(struct work_struct *ws);
791 static void hub_init_func3(struct work_struct *ws);
793 static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
795 struct usb_device *hdev = hub->hdev;
800 bool need_debounce_delay = false;
803 /* Continue a partial initialization */
804 if (type == HUB_INIT2 || type == HUB_INIT3) {
805 device_lock(hub->intfdev);
807 /* Was the hub disconnected while we were waiting? */
808 if (hub->disconnected) {
809 device_unlock(hub->intfdev);
810 kref_put(&hub->kref, hub_release);
813 if (type == HUB_INIT2)
817 kref_get(&hub->kref);
819 /* The superspeed hub except for root hub has to use Hub Depth
820 * value as an offset into the route string to locate the bits
821 * it uses to determine the downstream port number. So hub driver
822 * should send a set hub depth request to superspeed hub after
823 * the superspeed hub is set configuration in initialization or
826 * After a resume, port power should still be on.
827 * For any other type of activation, turn it on.
829 if (type != HUB_RESUME) {
830 if (hdev->parent && hub_is_superspeed(hdev)) {
831 ret = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
832 HUB_SET_DEPTH, USB_RT_HUB,
833 hdev->level - 1, 0, NULL, 0,
834 USB_CTRL_SET_TIMEOUT);
836 dev_err(hub->intfdev,
837 "set hub depth failed\n");
840 /* Speed up system boot by using a delayed_work for the
841 * hub's initial power-up delays. This is pretty awkward
842 * and the implementation looks like a home-brewed sort of
843 * setjmp/longjmp, but it saves at least 100 ms for each
844 * root hub (assuming usbcore is compiled into the kernel
845 * rather than as a module). It adds up.
847 * This can't be done for HUB_RESUME or HUB_RESET_RESUME
848 * because for those activation types the ports have to be
849 * operational when we return. In theory this could be done
850 * for HUB_POST_RESET, but it's easier not to.
852 if (type == HUB_INIT) {
853 delay = hub_power_on(hub, false);
854 PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func2);
855 schedule_delayed_work(&hub->init_work,
856 msecs_to_jiffies(delay));
858 /* Suppress autosuspend until init is done */
859 usb_autopm_get_interface_no_resume(
860 to_usb_interface(hub->intfdev));
861 return; /* Continues at init2: below */
862 } else if (type == HUB_RESET_RESUME) {
863 /* The internal host controller state for the hub device
864 * may be gone after a host power loss on system resume.
865 * Update the device's info so the HW knows it's a hub.
867 hcd = bus_to_hcd(hdev->bus);
868 if (hcd->driver->update_hub_device) {
869 ret = hcd->driver->update_hub_device(hcd, hdev,
872 dev_err(hub->intfdev, "Host not "
873 "accepting hub info "
875 dev_err(hub->intfdev, "LS/FS devices "
876 "and hubs may not work "
877 "under this hub\n.");
880 hub_power_on(hub, true);
882 hub_power_on(hub, true);
887 /* Check each port and set hub->change_bits to let khubd know
888 * which ports need attention.
890 for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
891 struct usb_device *udev = hdev->children[port1-1];
892 u16 portstatus, portchange;
894 portstatus = portchange = 0;
895 status = hub_port_status(hub, port1, &portstatus, &portchange);
899 if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
900 dev_dbg(hub->intfdev,
901 "port %d: status %04x change %04x\n",
902 port1, portstatus, portchange);
904 /* After anything other than HUB_RESUME (i.e., initialization
905 * or any sort of reset), every port should be disabled.
906 * Unconnected ports should likewise be disabled (paranoia),
907 * and so should ports for which we have no usb_device.
909 if ((portstatus & USB_PORT_STAT_ENABLE) && (
910 type != HUB_RESUME ||
911 !(portstatus & USB_PORT_STAT_CONNECTION) ||
913 udev->state == USB_STATE_NOTATTACHED)) {
915 * USB3 protocol ports will automatically transition
916 * to Enabled state when detect an USB3.0 device attach.
917 * Do not disable USB3 protocol ports.
919 if (!hub_is_superspeed(hdev)) {
920 clear_port_feature(hdev, port1,
921 USB_PORT_FEAT_ENABLE);
922 portstatus &= ~USB_PORT_STAT_ENABLE;
924 /* Pretend that power was lost for USB3 devs */
925 portstatus &= ~USB_PORT_STAT_ENABLE;
929 /* Clear status-change flags; we'll debounce later */
930 if (portchange & USB_PORT_STAT_C_CONNECTION) {
931 need_debounce_delay = true;
932 clear_port_feature(hub->hdev, port1,
933 USB_PORT_FEAT_C_CONNECTION);
935 if (portchange & USB_PORT_STAT_C_ENABLE) {
936 need_debounce_delay = true;
937 clear_port_feature(hub->hdev, port1,
938 USB_PORT_FEAT_C_ENABLE);
940 if (portchange & USB_PORT_STAT_C_LINK_STATE) {
941 need_debounce_delay = true;
942 clear_port_feature(hub->hdev, port1,
943 USB_PORT_FEAT_C_PORT_LINK_STATE);
945 if (portchange & USB_PORT_STAT_C_RESET) {
946 need_debounce_delay = true;
947 clear_port_feature(hub->hdev, port1,
948 USB_PORT_FEAT_C_RESET);
951 if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
952 hub_is_superspeed(hub->hdev)) {
953 need_debounce_delay = true;
954 clear_port_feature(hub->hdev, port1,
955 USB_PORT_FEAT_C_BH_PORT_RESET);
957 /* We can forget about a "removed" device when there's a
958 * physical disconnect or the connect status changes.
960 if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
961 (portchange & USB_PORT_STAT_C_CONNECTION))
962 clear_bit(port1, hub->removed_bits);
964 if (!udev || udev->state == USB_STATE_NOTATTACHED) {
965 /* Tell khubd to disconnect the device or
966 * check for a new connection
968 if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
969 set_bit(port1, hub->change_bits);
971 } else if (portstatus & USB_PORT_STAT_ENABLE) {
972 /* The power session apparently survived the resume.
973 * If there was an overcurrent or suspend change
974 * (i.e., remote wakeup request), have khubd
978 set_bit(port1, hub->change_bits);
980 } else if (udev->persist_enabled) {
982 udev->reset_resume = 1;
984 set_bit(port1, hub->change_bits);
987 /* The power session is gone; tell khubd */
988 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
989 set_bit(port1, hub->change_bits);
993 /* If no port-status-change flags were set, we don't need any
994 * debouncing. If flags were set we can try to debounce the
995 * ports all at once right now, instead of letting khubd do them
996 * one at a time later on.
998 * If any port-status changes do occur during this delay, khubd
999 * will see them later and handle them normally.
1001 if (need_debounce_delay) {
1002 delay = HUB_DEBOUNCE_STABLE;
1004 /* Don't do a long sleep inside a workqueue routine */
1005 if (type == HUB_INIT2) {
1006 PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func3);
1007 schedule_delayed_work(&hub->init_work,
1008 msecs_to_jiffies(delay));
1009 device_unlock(hub->intfdev);
1010 return; /* Continues at init3: below */
1018 status = usb_submit_urb(hub->urb, GFP_NOIO);
1020 dev_err(hub->intfdev, "activate --> %d\n", status);
1021 if (hub->has_indicators && blinkenlights)
1022 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
1024 /* Scan all ports that need attention */
1027 /* Allow autosuspend if it was suppressed */
1028 if (type <= HUB_INIT3)
1029 usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
1031 if (type == HUB_INIT2 || type == HUB_INIT3)
1032 device_unlock(hub->intfdev);
1034 kref_put(&hub->kref, hub_release);
1037 /* Implement the continuations for the delays above */
1038 static void hub_init_func2(struct work_struct *ws)
1040 struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1042 hub_activate(hub, HUB_INIT2);
1045 static void hub_init_func3(struct work_struct *ws)
1047 struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1049 hub_activate(hub, HUB_INIT3);
1052 enum hub_quiescing_type {
1053 HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
1056 static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
1058 struct usb_device *hdev = hub->hdev;
1061 cancel_delayed_work_sync(&hub->init_work);
1063 /* khubd and related activity won't re-trigger */
1066 if (type != HUB_SUSPEND) {
1067 /* Disconnect all the children */
1068 for (i = 0; i < hdev->maxchild; ++i) {
1069 if (hdev->children[i])
1070 usb_disconnect(&hdev->children[i]);
1074 /* Stop khubd and related activity */
1075 usb_kill_urb(hub->urb);
1076 if (hub->has_indicators)
1077 cancel_delayed_work_sync(&hub->leds);
1079 flush_work_sync(&hub->tt.clear_work);
1082 /* caller has locked the hub device */
1083 static int hub_pre_reset(struct usb_interface *intf)
1085 struct usb_hub *hub = usb_get_intfdata(intf);
1087 hub_quiesce(hub, HUB_PRE_RESET);
1091 /* caller has locked the hub device */
1092 static int hub_post_reset(struct usb_interface *intf)
1094 struct usb_hub *hub = usb_get_intfdata(intf);
1096 hub_activate(hub, HUB_POST_RESET);
1100 static int hub_configure(struct usb_hub *hub,
1101 struct usb_endpoint_descriptor *endpoint)
1103 struct usb_hcd *hcd;
1104 struct usb_device *hdev = hub->hdev;
1105 struct device *hub_dev = hub->intfdev;
1106 u16 hubstatus, hubchange;
1107 u16 wHubCharacteristics;
1110 char *message = "out of memory";
1113 hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
1119 hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
1124 mutex_init(&hub->status_mutex);
1126 hub->descriptor = kzalloc(sizeof(*hub->descriptor), GFP_KERNEL);
1127 if (!hub->descriptor) {
1132 /* Request the entire hub descriptor.
1133 * hub->descriptor can handle USB_MAXCHILDREN ports,
1134 * but a (non-SS) hub can/will return fewer bytes here.
1136 ret = get_hub_descriptor(hdev, hub->descriptor);
1138 message = "can't read hub descriptor";
1142 maxchild = USB_MAXCHILDREN;
1143 if (hub_is_superspeed(hdev))
1144 maxchild = min_t(unsigned, maxchild, USB_SS_MAXPORTS);
1146 if (hub->descriptor->bNbrPorts > maxchild) {
1147 message = "hub has too many ports!";
1152 hdev->maxchild = hub->descriptor->bNbrPorts;
1153 dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
1154 (hdev->maxchild == 1) ? "" : "s");
1156 hub->port_owners = kzalloc(hdev->maxchild * sizeof(void *), GFP_KERNEL);
1157 if (!hub->port_owners) {
1162 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
1164 /* FIXME for USB 3.0, skip for now */
1165 if ((wHubCharacteristics & HUB_CHAR_COMPOUND) &&
1166 !(hub_is_superspeed(hdev))) {
1168 char portstr [USB_MAXCHILDREN + 1];
1170 for (i = 0; i < hdev->maxchild; i++)
1171 portstr[i] = hub->descriptor->u.hs.DeviceRemovable
1172 [((i + 1) / 8)] & (1 << ((i + 1) % 8))
1174 portstr[hdev->maxchild] = 0;
1175 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
1177 dev_dbg(hub_dev, "standalone hub\n");
1179 switch (wHubCharacteristics & HUB_CHAR_LPSM) {
1181 dev_dbg(hub_dev, "ganged power switching\n");
1184 dev_dbg(hub_dev, "individual port power switching\n");
1188 dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
1192 switch (wHubCharacteristics & HUB_CHAR_OCPM) {
1194 dev_dbg(hub_dev, "global over-current protection\n");
1197 dev_dbg(hub_dev, "individual port over-current protection\n");
1201 dev_dbg(hub_dev, "no over-current protection\n");
1205 spin_lock_init (&hub->tt.lock);
1206 INIT_LIST_HEAD (&hub->tt.clear_list);
1207 INIT_WORK(&hub->tt.clear_work, hub_tt_work);
1208 switch (hdev->descriptor.bDeviceProtocol) {
1212 dev_dbg(hub_dev, "Single TT\n");
1216 ret = usb_set_interface(hdev, 0, 1);
1218 dev_dbg(hub_dev, "TT per port\n");
1221 dev_err(hub_dev, "Using single TT (err %d)\n",
1226 /* USB 3.0 hubs don't have a TT */
1229 dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
1230 hdev->descriptor.bDeviceProtocol);
1234 /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
1235 switch (wHubCharacteristics & HUB_CHAR_TTTT) {
1236 case HUB_TTTT_8_BITS:
1237 if (hdev->descriptor.bDeviceProtocol != 0) {
1238 hub->tt.think_time = 666;
1239 dev_dbg(hub_dev, "TT requires at most %d "
1240 "FS bit times (%d ns)\n",
1241 8, hub->tt.think_time);
1244 case HUB_TTTT_16_BITS:
1245 hub->tt.think_time = 666 * 2;
1246 dev_dbg(hub_dev, "TT requires at most %d "
1247 "FS bit times (%d ns)\n",
1248 16, hub->tt.think_time);
1250 case HUB_TTTT_24_BITS:
1251 hub->tt.think_time = 666 * 3;
1252 dev_dbg(hub_dev, "TT requires at most %d "
1253 "FS bit times (%d ns)\n",
1254 24, hub->tt.think_time);
1256 case HUB_TTTT_32_BITS:
1257 hub->tt.think_time = 666 * 4;
1258 dev_dbg(hub_dev, "TT requires at most %d "
1259 "FS bit times (%d ns)\n",
1260 32, hub->tt.think_time);
1264 /* probe() zeroes hub->indicator[] */
1265 if (wHubCharacteristics & HUB_CHAR_PORTIND) {
1266 hub->has_indicators = 1;
1267 dev_dbg(hub_dev, "Port indicators are supported\n");
1270 dev_dbg(hub_dev, "power on to power good time: %dms\n",
1271 hub->descriptor->bPwrOn2PwrGood * 2);
1273 /* power budgeting mostly matters with bus-powered hubs,
1274 * and battery-powered root hubs (may provide just 8 mA).
1276 ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
1278 message = "can't get hub status";
1281 le16_to_cpus(&hubstatus);
1282 if (hdev == hdev->bus->root_hub) {
1283 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
1284 hub->mA_per_port = 500;
1286 hub->mA_per_port = hdev->bus_mA;
1287 hub->limited_power = 1;
1289 } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1290 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
1291 hub->descriptor->bHubContrCurrent);
1292 hub->limited_power = 1;
1293 if (hdev->maxchild > 0) {
1294 int remaining = hdev->bus_mA -
1295 hub->descriptor->bHubContrCurrent;
1297 if (remaining < hdev->maxchild * 100)
1299 "insufficient power available "
1300 "to use all downstream ports\n");
1301 hub->mA_per_port = 100; /* 7.2.1.1 */
1303 } else { /* Self-powered external hub */
1304 /* FIXME: What about battery-powered external hubs that
1305 * provide less current per port? */
1306 hub->mA_per_port = 500;
1308 if (hub->mA_per_port < 500)
1309 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
1312 /* Update the HCD's internal representation of this hub before khubd
1313 * starts getting port status changes for devices under the hub.
1315 hcd = bus_to_hcd(hdev->bus);
1316 if (hcd->driver->update_hub_device) {
1317 ret = hcd->driver->update_hub_device(hcd, hdev,
1318 &hub->tt, GFP_KERNEL);
1320 message = "can't update HCD hub info";
1325 ret = hub_hub_status(hub, &hubstatus, &hubchange);
1327 message = "can't get hub status";
1331 /* local power status reports aren't always correct */
1332 if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
1333 dev_dbg(hub_dev, "local power source is %s\n",
1334 (hubstatus & HUB_STATUS_LOCAL_POWER)
1335 ? "lost (inactive)" : "good");
1337 if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
1338 dev_dbg(hub_dev, "%sover-current condition exists\n",
1339 (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
1341 /* set up the interrupt endpoint
1342 * We use the EP's maxpacket size instead of (PORTS+1+7)/8
1343 * bytes as USB2.0[11.12.3] says because some hubs are known
1344 * to send more data (and thus cause overflow). For root hubs,
1345 * maxpktsize is defined in hcd.c's fake endpoint descriptors
1346 * to be big enough for at least USB_MAXCHILDREN ports. */
1347 pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
1348 maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
1350 if (maxp > sizeof(*hub->buffer))
1351 maxp = sizeof(*hub->buffer);
1353 hub->urb = usb_alloc_urb(0, GFP_KERNEL);
1359 usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1360 hub, endpoint->bInterval);
1362 /* maybe cycle the hub leds */
1363 if (hub->has_indicators && blinkenlights)
1364 hub->indicator [0] = INDICATOR_CYCLE;
1366 hub_activate(hub, HUB_INIT);
1370 dev_err (hub_dev, "config failed, %s (err %d)\n",
1372 /* hub_disconnect() frees urb and descriptor */
1376 static void hub_release(struct kref *kref)
1378 struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1380 usb_put_intf(to_usb_interface(hub->intfdev));
1384 static unsigned highspeed_hubs;
1386 static void hub_disconnect(struct usb_interface *intf)
1388 struct usb_hub *hub = usb_get_intfdata (intf);
1390 /* Take the hub off the event list and don't let it be added again */
1391 spin_lock_irq(&hub_event_lock);
1392 if (!list_empty(&hub->event_list)) {
1393 list_del_init(&hub->event_list);
1394 usb_autopm_put_interface_no_suspend(intf);
1396 hub->disconnected = 1;
1397 spin_unlock_irq(&hub_event_lock);
1399 /* Disconnect all children and quiesce the hub */
1401 hub_quiesce(hub, HUB_DISCONNECT);
1403 usb_set_intfdata (intf, NULL);
1404 hub->hdev->maxchild = 0;
1406 if (hub->hdev->speed == USB_SPEED_HIGH)
1409 usb_free_urb(hub->urb);
1410 kfree(hub->port_owners);
1411 kfree(hub->descriptor);
1415 kref_put(&hub->kref, hub_release);
1418 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1420 struct usb_host_interface *desc;
1421 struct usb_endpoint_descriptor *endpoint;
1422 struct usb_device *hdev;
1423 struct usb_hub *hub;
1425 desc = intf->cur_altsetting;
1426 hdev = interface_to_usbdev(intf);
1429 * Hubs have proper suspend/resume support, except for root hubs
1430 * where the controller driver doesn't have bus_suspend and
1431 * bus_resume methods. Also, USB 3.0 device suspend is
1432 * different from USB 2.0/1.1 device suspend, and unfortunately we
1433 * don't support it yet. So leave autosuspend disabled for USB 3.0
1434 * external hubs for now. Enable autosuspend for USB 3.0 roothubs,
1435 * since that isn't a "real" hub.
1437 if (hdev->parent) { /* normal device */
1438 if (!hub_is_superspeed(hdev))
1439 usb_enable_autosuspend(hdev);
1440 } else { /* root hub */
1441 const struct hc_driver *drv = bus_to_hcd(hdev->bus)->driver;
1443 if (drv->bus_suspend && drv->bus_resume)
1444 usb_enable_autosuspend(hdev);
1447 if (hdev->level == MAX_TOPO_LEVEL) {
1449 "Unsupported bus topology: hub nested too deep\n");
1453 #ifdef CONFIG_USB_OTG_BLACKLIST_HUB
1455 dev_warn(&intf->dev, "ignoring external hub\n");
1460 /* Some hubs have a subclass of 1, which AFAICT according to the */
1461 /* specs is not defined, but it works */
1462 if ((desc->desc.bInterfaceSubClass != 0) &&
1463 (desc->desc.bInterfaceSubClass != 1)) {
1465 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
1469 /* Multiple endpoints? What kind of mutant ninja-hub is this? */
1470 if (desc->desc.bNumEndpoints != 1)
1471 goto descriptor_error;
1473 endpoint = &desc->endpoint[0].desc;
1475 /* If it's not an interrupt in endpoint, we'd better punt! */
1476 if (!usb_endpoint_is_int_in(endpoint))
1477 goto descriptor_error;
1479 /* We found a hub */
1480 dev_info (&intf->dev, "USB hub found\n");
1482 hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1484 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
1488 kref_init(&hub->kref);
1489 INIT_LIST_HEAD(&hub->event_list);
1490 hub->intfdev = &intf->dev;
1492 INIT_DELAYED_WORK(&hub->leds, led_work);
1493 INIT_DELAYED_WORK(&hub->init_work, NULL);
1496 usb_set_intfdata (intf, hub);
1497 intf->needs_remote_wakeup = 1;
1499 if (hdev->speed == USB_SPEED_HIGH)
1502 if (hub_configure(hub, endpoint) >= 0)
1505 hub_disconnect (intf);
1511 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1513 struct usb_device *hdev = interface_to_usbdev (intf);
1515 /* assert ifno == 0 (part of hub spec) */
1517 case USBDEVFS_HUB_PORTINFO: {
1518 struct usbdevfs_hub_portinfo *info = user_data;
1521 spin_lock_irq(&device_state_lock);
1522 if (hdev->devnum <= 0)
1525 info->nports = hdev->maxchild;
1526 for (i = 0; i < info->nports; i++) {
1527 if (hdev->children[i] == NULL)
1531 hdev->children[i]->devnum;
1534 spin_unlock_irq(&device_state_lock);
1536 return info->nports + 1;
1545 * Allow user programs to claim ports on a hub. When a device is attached
1546 * to one of these "claimed" ports, the program will "own" the device.
1548 static int find_port_owner(struct usb_device *hdev, unsigned port1,
1551 if (hdev->state == USB_STATE_NOTATTACHED)
1553 if (port1 == 0 || port1 > hdev->maxchild)
1556 /* This assumes that devices not managed by the hub driver
1557 * will always have maxchild equal to 0.
1559 *ppowner = &(hdev_to_hub(hdev)->port_owners[port1 - 1]);
1563 /* In the following three functions, the caller must hold hdev's lock */
1564 int usb_hub_claim_port(struct usb_device *hdev, unsigned port1, void *owner)
1569 rc = find_port_owner(hdev, port1, &powner);
1578 int usb_hub_release_port(struct usb_device *hdev, unsigned port1, void *owner)
1583 rc = find_port_owner(hdev, port1, &powner);
1586 if (*powner != owner)
1592 void usb_hub_release_all_ports(struct usb_device *hdev, void *owner)
1597 n = find_port_owner(hdev, 1, &powner);
1599 for (; n < hdev->maxchild; (++n, ++powner)) {
1600 if (*powner == owner)
1606 /* The caller must hold udev's lock */
1607 bool usb_device_is_owned(struct usb_device *udev)
1609 struct usb_hub *hub;
1611 if (udev->state == USB_STATE_NOTATTACHED || !udev->parent)
1613 hub = hdev_to_hub(udev->parent);
1614 return !!hub->port_owners[udev->portnum - 1];
1618 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1622 for (i = 0; i < udev->maxchild; ++i) {
1623 if (udev->children[i])
1624 recursively_mark_NOTATTACHED(udev->children[i]);
1626 if (udev->state == USB_STATE_SUSPENDED)
1627 udev->active_duration -= jiffies;
1628 udev->state = USB_STATE_NOTATTACHED;
1632 * usb_set_device_state - change a device's current state (usbcore, hcds)
1633 * @udev: pointer to device whose state should be changed
1634 * @new_state: new state value to be stored
1636 * udev->state is _not_ fully protected by the device lock. Although
1637 * most transitions are made only while holding the lock, the state can
1638 * can change to USB_STATE_NOTATTACHED at almost any time. This
1639 * is so that devices can be marked as disconnected as soon as possible,
1640 * without having to wait for any semaphores to be released. As a result,
1641 * all changes to any device's state must be protected by the
1642 * device_state_lock spinlock.
1644 * Once a device has been added to the device tree, all changes to its state
1645 * should be made using this routine. The state should _not_ be set directly.
1647 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1648 * Otherwise udev->state is set to new_state, and if new_state is
1649 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1650 * to USB_STATE_NOTATTACHED.
1652 void usb_set_device_state(struct usb_device *udev,
1653 enum usb_device_state new_state)
1655 unsigned long flags;
1658 spin_lock_irqsave(&device_state_lock, flags);
1659 if (udev->state == USB_STATE_NOTATTACHED)
1661 else if (new_state != USB_STATE_NOTATTACHED) {
1663 /* root hub wakeup capabilities are managed out-of-band
1664 * and may involve silicon errata ... ignore them here.
1667 if (udev->state == USB_STATE_SUSPENDED
1668 || new_state == USB_STATE_SUSPENDED)
1669 ; /* No change to wakeup settings */
1670 else if (new_state == USB_STATE_CONFIGURED)
1671 wakeup = (udev->quirks &
1672 USB_QUIRK_IGNORE_REMOTE_WAKEUP) ? 0 :
1673 udev->actconfig->desc.bmAttributes &
1674 USB_CONFIG_ATT_WAKEUP;
1678 if (udev->state == USB_STATE_SUSPENDED &&
1679 new_state != USB_STATE_SUSPENDED)
1680 udev->active_duration -= jiffies;
1681 else if (new_state == USB_STATE_SUSPENDED &&
1682 udev->state != USB_STATE_SUSPENDED)
1683 udev->active_duration += jiffies;
1684 udev->state = new_state;
1686 recursively_mark_NOTATTACHED(udev);
1687 spin_unlock_irqrestore(&device_state_lock, flags);
1689 device_set_wakeup_capable(&udev->dev, wakeup);
1691 EXPORT_SYMBOL_GPL(usb_set_device_state);
1694 * Choose a device number.
1696 * Device numbers are used as filenames in usbfs. On USB-1.1 and
1697 * USB-2.0 buses they are also used as device addresses, however on
1698 * USB-3.0 buses the address is assigned by the controller hardware
1699 * and it usually is not the same as the device number.
1701 * WUSB devices are simple: they have no hubs behind, so the mapping
1702 * device <-> virtual port number becomes 1:1. Why? to simplify the
1703 * life of the device connection logic in
1704 * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
1705 * handshake we need to assign a temporary address in the unauthorized
1706 * space. For simplicity we use the first virtual port number found to
1707 * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
1708 * and that becomes it's address [X < 128] or its unauthorized address
1711 * We add 1 as an offset to the one-based USB-stack port number
1712 * (zero-based wusb virtual port index) for two reasons: (a) dev addr
1713 * 0 is reserved by USB for default address; (b) Linux's USB stack
1714 * uses always #1 for the root hub of the controller. So USB stack's
1715 * port #1, which is wusb virtual-port #0 has address #2.
1717 * Devices connected under xHCI are not as simple. The host controller
1718 * supports virtualization, so the hardware assigns device addresses and
1719 * the HCD must setup data structures before issuing a set address
1720 * command to the hardware.
1722 static void choose_devnum(struct usb_device *udev)
1725 struct usb_bus *bus = udev->bus;
1727 /* If khubd ever becomes multithreaded, this will need a lock */
1729 devnum = udev->portnum + 1;
1730 BUG_ON(test_bit(devnum, bus->devmap.devicemap));
1732 /* Try to allocate the next devnum beginning at
1733 * bus->devnum_next. */
1734 devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1737 devnum = find_next_zero_bit(bus->devmap.devicemap,
1739 bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1742 set_bit(devnum, bus->devmap.devicemap);
1743 udev->devnum = devnum;
1747 static void release_devnum(struct usb_device *udev)
1749 if (udev->devnum > 0) {
1750 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1755 static void update_devnum(struct usb_device *udev, int devnum)
1757 /* The address for a WUSB device is managed by wusbcore. */
1759 udev->devnum = devnum;
1762 static void hub_free_dev(struct usb_device *udev)
1764 struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1766 /* Root hubs aren't real devices, so don't free HCD resources */
1767 if (hcd->driver->free_dev && udev->parent)
1768 hcd->driver->free_dev(hcd, udev);
1772 * usb_disconnect - disconnect a device (usbcore-internal)
1773 * @pdev: pointer to device being disconnected
1774 * Context: !in_interrupt ()
1776 * Something got disconnected. Get rid of it and all of its children.
1778 * If *pdev is a normal device then the parent hub must already be locked.
1779 * If *pdev is a root hub then this routine will acquire the
1780 * usb_bus_list_lock on behalf of the caller.
1782 * Only hub drivers (including virtual root hub drivers for host
1783 * controllers) should ever call this.
1785 * This call is synchronous, and may not be used in an interrupt context.
1787 void usb_disconnect(struct usb_device **pdev)
1789 struct usb_device *udev = *pdev;
1792 /* mark the device as inactive, so any further urb submissions for
1793 * this device (and any of its children) will fail immediately.
1794 * this quiesces everything except pending urbs.
1796 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1797 dev_info(&udev->dev, "USB disconnect, device number %d\n",
1801 * Ensure that the pm runtime code knows that the USB device
1802 * is in the process of being disconnected.
1804 pm_runtime_barrier(&udev->dev);
1806 usb_lock_device(udev);
1808 /* Free up all the children before we remove this device */
1809 for (i = 0; i < USB_MAXCHILDREN; i++) {
1810 if (udev->children[i])
1811 usb_disconnect(&udev->children[i]);
1814 /* deallocate hcd/hardware state ... nuking all pending urbs and
1815 * cleaning up all state associated with the current configuration
1816 * so that the hardware is now fully quiesced.
1818 dev_dbg (&udev->dev, "unregistering device\n");
1819 usb_disable_device(udev, 0);
1820 usb_hcd_synchronize_unlinks(udev);
1822 usb_remove_ep_devs(&udev->ep0);
1823 usb_unlock_device(udev);
1825 /* Unregister the device. The device driver is responsible
1826 * for de-configuring the device and invoking the remove-device
1827 * notifier chain (used by usbfs and possibly others).
1829 device_del(&udev->dev);
1831 /* Free the device number and delete the parent's children[]
1832 * (or root_hub) pointer.
1834 release_devnum(udev);
1836 /* Avoid races with recursively_mark_NOTATTACHED() */
1837 spin_lock_irq(&device_state_lock);
1839 spin_unlock_irq(&device_state_lock);
1843 put_device(&udev->dev);
1846 #ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
1847 static void show_string(struct usb_device *udev, char *id, char *string)
1851 dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1854 static void announce_device(struct usb_device *udev)
1856 dev_info(&udev->dev, "New USB device found, idVendor=%04x, idProduct=%04x\n",
1857 le16_to_cpu(udev->descriptor.idVendor),
1858 le16_to_cpu(udev->descriptor.idProduct));
1859 dev_info(&udev->dev,
1860 "New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
1861 udev->descriptor.iManufacturer,
1862 udev->descriptor.iProduct,
1863 udev->descriptor.iSerialNumber);
1864 show_string(udev, "Product", udev->product);
1865 show_string(udev, "Manufacturer", udev->manufacturer);
1866 show_string(udev, "SerialNumber", udev->serial);
1869 static inline void announce_device(struct usb_device *udev) { }
1872 #ifdef CONFIG_USB_OTG
1873 #include "otg_whitelist.h"
1877 * usb_enumerate_device_otg - FIXME (usbcore-internal)
1878 * @udev: newly addressed device (in ADDRESS state)
1880 * Finish enumeration for On-The-Go devices
1882 static int usb_enumerate_device_otg(struct usb_device *udev)
1886 #ifdef CONFIG_USB_OTG
1888 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1889 * to wake us after we've powered off VBUS; and HNP, switching roles
1890 * "host" to "peripheral". The OTG descriptor helps figure this out.
1892 if (!udev->bus->is_b_host
1894 && udev->parent == udev->bus->root_hub) {
1895 struct usb_otg_descriptor *desc = NULL;
1896 struct usb_bus *bus = udev->bus;
1898 /* descriptor may appear anywhere in config */
1899 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1900 le16_to_cpu(udev->config[0].desc.wTotalLength),
1901 USB_DT_OTG, (void **) &desc) == 0) {
1902 if (desc->bmAttributes & USB_OTG_HNP) {
1903 unsigned port1 = udev->portnum;
1905 dev_info(&udev->dev,
1906 "Dual-Role OTG device on %sHNP port\n",
1907 (port1 == bus->otg_port)
1910 /* enable HNP before suspend, it's simpler */
1911 if (port1 == bus->otg_port)
1912 bus->b_hnp_enable = 1;
1913 err = usb_control_msg(udev,
1914 usb_sndctrlpipe(udev, 0),
1915 USB_REQ_SET_FEATURE, 0,
1917 ? USB_DEVICE_B_HNP_ENABLE
1918 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1919 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1921 /* OTG MESSAGE: report errors here,
1922 * customize to match your product.
1924 dev_info(&udev->dev,
1925 "can't set HNP mode: %d\n",
1927 bus->b_hnp_enable = 0;
1933 if (!is_targeted(udev)) {
1935 /* Maybe it can talk to us, though we can't talk to it.
1936 * (Includes HNP test device.)
1938 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1939 err = usb_port_suspend(udev, PMSG_SUSPEND);
1941 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1953 * usb_enumerate_device - Read device configs/intfs/otg (usbcore-internal)
1954 * @udev: newly addressed device (in ADDRESS state)
1956 * This is only called by usb_new_device() and usb_authorize_device()
1957 * and FIXME -- all comments that apply to them apply here wrt to
1960 * If the device is WUSB and not authorized, we don't attempt to read
1961 * the string descriptors, as they will be errored out by the device
1962 * until it has been authorized.
1964 static int usb_enumerate_device(struct usb_device *udev)
1968 if (udev->config == NULL) {
1969 err = usb_get_configuration(udev);
1971 dev_err(&udev->dev, "can't read configurations, error %d\n",
1976 if (udev->wusb == 1 && udev->authorized == 0) {
1977 udev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1978 udev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1979 udev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1982 /* read the standard strings and cache them if present */
1983 udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1984 udev->manufacturer = usb_cache_string(udev,
1985 udev->descriptor.iManufacturer);
1986 udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1988 err = usb_enumerate_device_otg(udev);
1992 usb_detect_interface_quirks(udev);
1999 * usb_new_device - perform initial device setup (usbcore-internal)
2000 * @udev: newly addressed device (in ADDRESS state)
2002 * This is called with devices which have been detected but not fully
2003 * enumerated. The device descriptor is available, but not descriptors
2004 * for any device configuration. The caller must have locked either
2005 * the parent hub (if udev is a normal device) or else the
2006 * usb_bus_list_lock (if udev is a root hub). The parent's pointer to
2007 * udev has already been installed, but udev is not yet visible through
2008 * sysfs or other filesystem code.
2010 * It will return if the device is configured properly or not. Zero if
2011 * the interface was registered with the driver core; else a negative
2014 * This call is synchronous, and may not be used in an interrupt context.
2016 * Only the hub driver or root-hub registrar should ever call this.
2018 int usb_new_device(struct usb_device *udev)
2023 /* Initialize non-root-hub device wakeup to disabled;
2024 * device (un)configuration controls wakeup capable
2025 * sysfs power/wakeup controls wakeup enabled/disabled
2027 device_init_wakeup(&udev->dev, 0);
2030 /* Tell the runtime-PM framework the device is active */
2031 pm_runtime_set_active(&udev->dev);
2032 pm_runtime_get_noresume(&udev->dev);
2033 pm_runtime_use_autosuspend(&udev->dev);
2034 pm_runtime_enable(&udev->dev);
2036 /* By default, forbid autosuspend for all devices. It will be
2037 * allowed for hubs during binding.
2039 usb_disable_autosuspend(udev);
2041 err = usb_enumerate_device(udev); /* Read descriptors */
2044 dev_dbg(&udev->dev, "udev %d, busnum %d, minor = %d\n",
2045 udev->devnum, udev->bus->busnum,
2046 (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2047 /* export the usbdev device-node for libusb */
2048 udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
2049 (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2051 /* Tell the world! */
2052 announce_device(udev);
2055 add_device_randomness(udev->serial, strlen(udev->serial));
2057 add_device_randomness(udev->product, strlen(udev->product));
2058 if (udev->manufacturer)
2059 add_device_randomness(udev->manufacturer,
2060 strlen(udev->manufacturer));
2062 device_enable_async_suspend(&udev->dev);
2063 /* Register the device. The device driver is responsible
2064 * for configuring the device and invoking the add-device
2065 * notifier chain (used by usbfs and possibly others).
2067 err = device_add(&udev->dev);
2069 dev_err(&udev->dev, "can't device_add, error %d\n", err);
2073 (void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev);
2074 usb_mark_last_busy(udev);
2075 pm_runtime_put_sync_autosuspend(&udev->dev);
2079 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2080 pm_runtime_disable(&udev->dev);
2081 pm_runtime_set_suspended(&udev->dev);
2087 * usb_deauthorize_device - deauthorize a device (usbcore-internal)
2088 * @usb_dev: USB device
2090 * Move the USB device to a very basic state where interfaces are disabled
2091 * and the device is in fact unconfigured and unusable.
2093 * We share a lock (that we have) with device_del(), so we need to
2096 int usb_deauthorize_device(struct usb_device *usb_dev)
2098 usb_lock_device(usb_dev);
2099 if (usb_dev->authorized == 0)
2100 goto out_unauthorized;
2102 usb_dev->authorized = 0;
2103 usb_set_configuration(usb_dev, -1);
2105 kfree(usb_dev->product);
2106 usb_dev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
2107 kfree(usb_dev->manufacturer);
2108 usb_dev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
2109 kfree(usb_dev->serial);
2110 usb_dev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
2112 usb_destroy_configuration(usb_dev);
2113 usb_dev->descriptor.bNumConfigurations = 0;
2116 usb_unlock_device(usb_dev);
2121 int usb_authorize_device(struct usb_device *usb_dev)
2125 usb_lock_device(usb_dev);
2126 if (usb_dev->authorized == 1)
2127 goto out_authorized;
2129 result = usb_autoresume_device(usb_dev);
2131 dev_err(&usb_dev->dev,
2132 "can't autoresume for authorization: %d\n", result);
2133 goto error_autoresume;
2135 result = usb_get_device_descriptor(usb_dev, sizeof(usb_dev->descriptor));
2137 dev_err(&usb_dev->dev, "can't re-read device descriptor for "
2138 "authorization: %d\n", result);
2139 goto error_device_descriptor;
2142 kfree(usb_dev->product);
2143 usb_dev->product = NULL;
2144 kfree(usb_dev->manufacturer);
2145 usb_dev->manufacturer = NULL;
2146 kfree(usb_dev->serial);
2147 usb_dev->serial = NULL;
2149 usb_dev->authorized = 1;
2150 result = usb_enumerate_device(usb_dev);
2152 goto error_enumerate;
2153 /* Choose and set the configuration. This registers the interfaces
2154 * with the driver core and lets interface drivers bind to them.
2156 c = usb_choose_configuration(usb_dev);
2158 result = usb_set_configuration(usb_dev, c);
2160 dev_err(&usb_dev->dev,
2161 "can't set config #%d, error %d\n", c, result);
2162 /* This need not be fatal. The user can try to
2163 * set other configurations. */
2166 dev_info(&usb_dev->dev, "authorized to connect\n");
2169 error_device_descriptor:
2170 usb_autosuspend_device(usb_dev);
2173 usb_unlock_device(usb_dev); // complements locktree
2178 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
2179 static unsigned hub_is_wusb(struct usb_hub *hub)
2181 struct usb_hcd *hcd;
2182 if (hub->hdev->parent != NULL) /* not a root hub? */
2184 hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
2185 return hcd->wireless;
2189 #define PORT_RESET_TRIES 5
2190 #define SET_ADDRESS_TRIES 2
2191 #define GET_DESCRIPTOR_TRIES 2
2192 #define SET_CONFIG_TRIES (2 * (use_both_schemes + 1))
2193 #define USE_NEW_SCHEME(i) ((i) / 2 == old_scheme_first)
2195 #define HUB_ROOT_RESET_TIME 50 /* times are in msec */
2196 #define HUB_SHORT_RESET_TIME 10
2197 #define HUB_BH_RESET_TIME 50
2198 #define HUB_LONG_RESET_TIME 200
2199 #define HUB_RESET_TIMEOUT 800
2201 /* Is a USB 3.0 port in the Inactive or Complinance Mode state?
2202 * Port worm reset is required to recover
2204 static bool hub_port_warm_reset_required(struct usb_hub *hub, u16 portstatus)
2206 return hub_is_superspeed(hub->hdev) &&
2207 (((portstatus & USB_PORT_STAT_LINK_STATE) ==
2208 USB_SS_PORT_LS_SS_INACTIVE) ||
2209 ((portstatus & USB_PORT_STAT_LINK_STATE) ==
2210 USB_SS_PORT_LS_COMP_MOD)) ;
2213 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
2214 struct usb_device *udev, unsigned int delay, bool warm)
2216 int delay_time, ret;
2220 for (delay_time = 0;
2221 delay_time < HUB_RESET_TIMEOUT;
2222 delay_time += delay) {
2223 /* wait to give the device a chance to reset */
2226 /* read and decode port status */
2227 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2231 /* The port state is unknown until the reset completes. */
2232 if ((portstatus & USB_PORT_STAT_RESET))
2235 if (hub_port_warm_reset_required(hub, portstatus))
2238 /* Device went away? */
2239 if (!(portstatus & USB_PORT_STAT_CONNECTION))
2242 /* bomb out completely if the connection bounced. A USB 3.0
2243 * connection may bounce if multiple warm resets were issued,
2244 * but the device may have successfully re-connected. Ignore it.
2246 if (!hub_is_superspeed(hub->hdev) &&
2247 (portchange & USB_PORT_STAT_C_CONNECTION))
2250 if ((portstatus & USB_PORT_STAT_ENABLE)) {
2254 if (hub_is_wusb(hub))
2255 udev->speed = USB_SPEED_WIRELESS;
2256 else if (hub_is_superspeed(hub->hdev))
2257 udev->speed = USB_SPEED_SUPER;
2258 else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
2259 udev->speed = USB_SPEED_HIGH;
2260 else if (portstatus & USB_PORT_STAT_LOW_SPEED)
2261 udev->speed = USB_SPEED_LOW;
2263 udev->speed = USB_SPEED_FULL;
2268 /* switch to the long delay after two short delay failures */
2269 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
2270 delay = HUB_LONG_RESET_TIME;
2272 dev_dbg (hub->intfdev,
2273 "port %d not %sreset yet, waiting %dms\n",
2274 port1, warm ? "warm " : "", delay);
2280 /* Handle port reset and port warm(BH) reset (for USB3 protocol ports) */
2281 static int hub_port_reset(struct usb_hub *hub, int port1,
2282 struct usb_device *udev, unsigned int delay, bool warm)
2285 u16 portchange, portstatus;
2287 if (!hub_is_superspeed(hub->hdev)) {
2289 dev_err(hub->intfdev, "only USB3 hub support "
2293 /* Block EHCI CF initialization during the port reset.
2294 * Some companion controllers don't like it when they mix.
2296 down_read(&ehci_cf_port_reset_rwsem);
2299 * If the caller hasn't explicitly requested a warm reset,
2300 * double check and see if one is needed.
2302 if (hub_port_status(hub, port1, &portstatus, &portchange) == 0)
2303 if (hub_port_warm_reset_required(hub, portstatus))
2307 /* Reset the port */
2308 for (i = 0; i < PORT_RESET_TRIES; i++) {
2309 status = set_port_feature(hub->hdev, port1, (warm ?
2310 USB_PORT_FEAT_BH_PORT_RESET :
2311 USB_PORT_FEAT_RESET));
2313 dev_err(hub->intfdev,
2314 "cannot %sreset port %d (err = %d)\n",
2315 warm ? "warm " : "", port1, status);
2317 status = hub_port_wait_reset(hub, port1, udev, delay,
2319 if (status && status != -ENOTCONN)
2320 dev_dbg(hub->intfdev,
2321 "port_wait_reset: err = %d\n",
2325 /* Check for disconnect or reset */
2326 if (status == 0 || status == -ENOTCONN || status == -ENODEV) {
2327 clear_port_feature(hub->hdev, port1,
2328 USB_PORT_FEAT_C_RESET);
2330 if (!hub_is_superspeed(hub->hdev))
2333 clear_port_feature(hub->hdev, port1,
2334 USB_PORT_FEAT_C_BH_PORT_RESET);
2335 clear_port_feature(hub->hdev, port1,
2336 USB_PORT_FEAT_C_PORT_LINK_STATE);
2337 clear_port_feature(hub->hdev, port1,
2338 USB_PORT_FEAT_C_CONNECTION);
2341 * If a USB 3.0 device migrates from reset to an error
2342 * state, re-issue the warm reset.
2344 if (hub_port_status(hub, port1,
2345 &portstatus, &portchange) < 0)
2348 if (!hub_port_warm_reset_required(hub, portstatus))
2352 * If the port is in SS.Inactive or Compliance Mode, the
2353 * hot or warm reset failed. Try another warm reset.
2356 dev_dbg(hub->intfdev, "hot reset failed, warm reset port %d\n",
2362 dev_dbg (hub->intfdev,
2363 "port %d not enabled, trying %sreset again...\n",
2364 port1, warm ? "warm " : "");
2365 delay = HUB_LONG_RESET_TIME;
2368 dev_err (hub->intfdev,
2369 "Cannot enable port %i. Maybe the USB cable is bad?\n",
2374 /* TRSTRCY = 10 ms; plus some extra */
2377 struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2379 update_devnum(udev, 0);
2380 /* The xHC may think the device is already reset,
2381 * so ignore the status.
2383 if (hcd->driver->reset_device)
2384 hcd->driver->reset_device(hcd, udev);
2386 usb_set_device_state(udev, USB_STATE_DEFAULT);
2390 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2393 if (!hub_is_superspeed(hub->hdev))
2394 up_read(&ehci_cf_port_reset_rwsem);
2399 /* Check if a port is power on */
2400 static int port_is_power_on(struct usb_hub *hub, unsigned portstatus)
2404 if (hub_is_superspeed(hub->hdev)) {
2405 if (portstatus & USB_SS_PORT_STAT_POWER)
2408 if (portstatus & USB_PORT_STAT_POWER)
2417 /* Check if a port is suspended(USB2.0 port) or in U3 state(USB3.0 port) */
2418 static int port_is_suspended(struct usb_hub *hub, unsigned portstatus)
2422 if (hub_is_superspeed(hub->hdev)) {
2423 if ((portstatus & USB_PORT_STAT_LINK_STATE)
2424 == USB_SS_PORT_LS_U3)
2427 if (portstatus & USB_PORT_STAT_SUSPEND)
2434 /* Determine whether the device on a port is ready for a normal resume,
2435 * is ready for a reset-resume, or should be disconnected.
2437 static int check_port_resume_type(struct usb_device *udev,
2438 struct usb_hub *hub, int port1,
2439 int status, unsigned portchange, unsigned portstatus)
2441 /* Is the device still present? */
2442 if (status || port_is_suspended(hub, portstatus) ||
2443 !port_is_power_on(hub, portstatus) ||
2444 !(portstatus & USB_PORT_STAT_CONNECTION)) {
2449 /* Can't do a normal resume if the port isn't enabled,
2450 * so try a reset-resume instead.
2452 else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
2453 if (udev->persist_enabled)
2454 udev->reset_resume = 1;
2460 dev_dbg(hub->intfdev,
2461 "port %d status %04x.%04x after resume, %d\n",
2462 port1, portchange, portstatus, status);
2463 } else if (udev->reset_resume) {
2465 /* Late port handoff can set status-change bits */
2466 if (portchange & USB_PORT_STAT_C_CONNECTION)
2467 clear_port_feature(hub->hdev, port1,
2468 USB_PORT_FEAT_C_CONNECTION);
2469 if (portchange & USB_PORT_STAT_C_ENABLE)
2470 clear_port_feature(hub->hdev, port1,
2471 USB_PORT_FEAT_C_ENABLE);
2477 #ifdef CONFIG_USB_SUSPEND
2480 * usb_port_suspend - suspend a usb device's upstream port
2481 * @udev: device that's no longer in active use, not a root hub
2482 * Context: must be able to sleep; device not locked; pm locks held
2484 * Suspends a USB device that isn't in active use, conserving power.
2485 * Devices may wake out of a suspend, if anything important happens,
2486 * using the remote wakeup mechanism. They may also be taken out of
2487 * suspend by the host, using usb_port_resume(). It's also routine
2488 * to disconnect devices while they are suspended.
2490 * This only affects the USB hardware for a device; its interfaces
2491 * (and, for hubs, child devices) must already have been suspended.
2493 * Selective port suspend reduces power; most suspended devices draw
2494 * less than 500 uA. It's also used in OTG, along with remote wakeup.
2495 * All devices below the suspended port are also suspended.
2497 * Devices leave suspend state when the host wakes them up. Some devices
2498 * also support "remote wakeup", where the device can activate the USB
2499 * tree above them to deliver data, such as a keypress or packet. In
2500 * some cases, this wakes the USB host.
2502 * Suspending OTG devices may trigger HNP, if that's been enabled
2503 * between a pair of dual-role devices. That will change roles, such
2504 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
2506 * Devices on USB hub ports have only one "suspend" state, corresponding
2507 * to ACPI D2, "may cause the device to lose some context".
2508 * State transitions include:
2510 * - suspend, resume ... when the VBUS power link stays live
2511 * - suspend, disconnect ... VBUS lost
2513 * Once VBUS drop breaks the circuit, the port it's using has to go through
2514 * normal re-enumeration procedures, starting with enabling VBUS power.
2515 * Other than re-initializing the hub (plug/unplug, except for root hubs),
2516 * Linux (2.6) currently has NO mechanisms to initiate that: no khubd
2517 * timer, no SRP, no requests through sysfs.
2519 * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
2520 * the root hub for their bus goes into global suspend ... so we don't
2521 * (falsely) update the device power state to say it suspended.
2523 * Returns 0 on success, else negative errno.
2525 int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
2527 struct usb_hub *hub = hdev_to_hub(udev->parent);
2528 int port1 = udev->portnum;
2531 /* enable remote wakeup when appropriate; this lets the device
2532 * wake up the upstream hub (including maybe the root hub).
2534 * NOTE: OTG devices may issue remote wakeup (or SRP) even when
2535 * we don't explicitly enable it here.
2537 if (udev->do_remote_wakeup) {
2538 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2539 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
2540 USB_DEVICE_REMOTE_WAKEUP, 0,
2542 USB_CTRL_SET_TIMEOUT);
2544 dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
2546 /* bail if autosuspend is requested */
2547 if (PMSG_IS_AUTO(msg))
2552 /* disable USB2 hardware LPM */
2553 if (udev->usb2_hw_lpm_enabled == 1)
2554 usb_set_usb2_hardware_lpm(udev, 0);
2557 if (hub_is_superspeed(hub->hdev))
2558 status = set_port_feature(hub->hdev,
2559 port1 | (USB_SS_PORT_LS_U3 << 3),
2560 USB_PORT_FEAT_LINK_STATE);
2562 status = set_port_feature(hub->hdev, port1,
2563 USB_PORT_FEAT_SUSPEND);
2565 dev_dbg(hub->intfdev, "can't suspend port %d, status %d\n",
2567 /* paranoia: "should not happen" */
2568 if (udev->do_remote_wakeup)
2569 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2570 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
2571 USB_DEVICE_REMOTE_WAKEUP, 0,
2573 USB_CTRL_SET_TIMEOUT);
2575 /* Try to enable USB2 hardware LPM again */
2576 if (udev->usb2_hw_lpm_capable == 1)
2577 usb_set_usb2_hardware_lpm(udev, 1);
2579 /* System sleep transitions should never fail */
2580 if (!PMSG_IS_AUTO(msg))
2583 /* device has up to 10 msec to fully suspend */
2584 dev_dbg(&udev->dev, "usb %ssuspend, wakeup %d\n",
2585 (PMSG_IS_AUTO(msg) ? "auto-" : ""),
2586 udev->do_remote_wakeup);
2587 usb_set_device_state(udev, USB_STATE_SUSPENDED);
2590 usb_mark_last_busy(hub->hdev);
2595 * If the USB "suspend" state is in use (rather than "global suspend"),
2596 * many devices will be individually taken out of suspend state using
2597 * special "resume" signaling. This routine kicks in shortly after
2598 * hardware resume signaling is finished, either because of selective
2599 * resume (by host) or remote wakeup (by device) ... now see what changed
2600 * in the tree that's rooted at this device.
2602 * If @udev->reset_resume is set then the device is reset before the
2603 * status check is done.
2605 static int finish_port_resume(struct usb_device *udev)
2610 /* caller owns the udev device lock */
2611 dev_dbg(&udev->dev, "%s\n",
2612 udev->reset_resume ? "finish reset-resume" : "finish resume");
2614 /* usb ch9 identifies four variants of SUSPENDED, based on what
2615 * state the device resumes to. Linux currently won't see the
2616 * first two on the host side; they'd be inside hub_port_init()
2617 * during many timeouts, but khubd can't suspend until later.
2619 usb_set_device_state(udev, udev->actconfig
2620 ? USB_STATE_CONFIGURED
2621 : USB_STATE_ADDRESS);
2623 /* 10.5.4.5 says not to reset a suspended port if the attached
2624 * device is enabled for remote wakeup. Hence the reset
2625 * operation is carried out here, after the port has been
2628 if (udev->reset_resume)
2630 status = usb_reset_and_verify_device(udev);
2632 /* 10.5.4.5 says be sure devices in the tree are still there.
2633 * For now let's assume the device didn't go crazy on resume,
2634 * and device drivers will know about any resume quirks.
2638 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
2640 status = (status > 0 ? 0 : -ENODEV);
2642 /* If a normal resume failed, try doing a reset-resume */
2643 if (status && !udev->reset_resume && udev->persist_enabled) {
2644 dev_dbg(&udev->dev, "retry with reset-resume\n");
2645 udev->reset_resume = 1;
2646 goto retry_reset_resume;
2651 dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
2654 * There are a few quirky devices which violate the standard
2655 * by claiming to have remote wakeup enabled after a reset,
2656 * which crash if the feature is cleared, hence check for
2657 * udev->reset_resume
2659 } else if (udev->actconfig && !udev->reset_resume) {
2660 le16_to_cpus(&devstatus);
2661 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
2662 status = usb_control_msg(udev,
2663 usb_sndctrlpipe(udev, 0),
2664 USB_REQ_CLEAR_FEATURE,
2666 USB_DEVICE_REMOTE_WAKEUP, 0,
2668 USB_CTRL_SET_TIMEOUT);
2671 "disable remote wakeup, status %d\n",
2680 * There are some SS USB devices which take longer time for link training.
2681 * XHCI specs 4.19.4 says that when Link training is successful, port
2682 * sets CSC bit to 1. So if SW reads port status before successful link
2683 * training, then it will not find device to be present.
2684 * USB Analyzer log with such buggy devices show that in some cases
2685 * device switch on the RX termination after long delay of host enabling
2686 * the VBUS. In few other cases it has been seen that device fails to
2687 * negotiate link training in first attempt. It has been
2688 * reported till now that few devices take as long as 2000 ms to train
2689 * the link after host enabling its VBUS and termination. Following
2690 * routine implements a 2000 ms timeout for link training. If in a case
2691 * link trains before timeout, loop will exit earlier.
2693 * FIXME: If a device was connected before suspend, but was removed
2694 * while system was asleep, then the loop in the following routine will
2695 * only exit at timeout.
2697 * This routine should only be called when persist is enabled for a SS
2700 static int wait_for_ss_port_enable(struct usb_device *udev,
2701 struct usb_hub *hub, int *port1,
2702 u16 *portchange, u16 *portstatus)
2704 int status = 0, delay_ms = 0;
2706 while (delay_ms < 2000) {
2707 if (status || *portstatus & USB_PORT_STAT_CONNECTION)
2711 status = hub_port_status(hub, *port1, portstatus, portchange);
2717 * usb_port_resume - re-activate a suspended usb device's upstream port
2718 * @udev: device to re-activate, not a root hub
2719 * Context: must be able to sleep; device not locked; pm locks held
2721 * This will re-activate the suspended device, increasing power usage
2722 * while letting drivers communicate again with its endpoints.
2723 * USB resume explicitly guarantees that the power session between
2724 * the host and the device is the same as it was when the device
2727 * If @udev->reset_resume is set then this routine won't check that the
2728 * port is still enabled. Furthermore, finish_port_resume() above will
2729 * reset @udev. The end result is that a broken power session can be
2730 * recovered and @udev will appear to persist across a loss of VBUS power.
2732 * For example, if a host controller doesn't maintain VBUS suspend current
2733 * during a system sleep or is reset when the system wakes up, all the USB
2734 * power sessions below it will be broken. This is especially troublesome
2735 * for mass-storage devices containing mounted filesystems, since the
2736 * device will appear to have disconnected and all the memory mappings
2737 * to it will be lost. Using the USB_PERSIST facility, the device can be
2738 * made to appear as if it had not disconnected.
2740 * This facility can be dangerous. Although usb_reset_and_verify_device() makes
2741 * every effort to insure that the same device is present after the
2742 * reset as before, it cannot provide a 100% guarantee. Furthermore it's
2743 * quite possible for a device to remain unaltered but its media to be
2744 * changed. If the user replaces a flash memory card while the system is
2745 * asleep, he will have only himself to blame when the filesystem on the
2746 * new card is corrupted and the system crashes.
2748 * Returns 0 on success, else negative errno.
2750 int usb_port_resume(struct usb_device *udev, pm_message_t msg)
2752 struct usb_hub *hub = hdev_to_hub(udev->parent);
2753 int port1 = udev->portnum;
2755 u16 portchange, portstatus;
2757 /* Skip the initial Clear-Suspend step for a remote wakeup */
2758 status = hub_port_status(hub, port1, &portstatus, &portchange);
2759 if (status == 0 && !port_is_suspended(hub, portstatus))
2760 goto SuspendCleared;
2762 // dev_dbg(hub->intfdev, "resume port %d\n", port1);
2764 set_bit(port1, hub->busy_bits);
2766 /* see 7.1.7.7; affects power usage, but not budgeting */
2767 if (hub_is_superspeed(hub->hdev))
2768 status = set_port_feature(hub->hdev,
2769 port1 | (USB_SS_PORT_LS_U0 << 3),
2770 USB_PORT_FEAT_LINK_STATE);
2772 status = clear_port_feature(hub->hdev,
2773 port1, USB_PORT_FEAT_SUSPEND);
2775 dev_dbg(hub->intfdev, "can't resume port %d, status %d\n",
2778 /* drive resume for at least 20 msec */
2779 dev_dbg(&udev->dev, "usb %sresume\n",
2780 (PMSG_IS_AUTO(msg) ? "auto-" : ""));
2783 /* Virtual root hubs can trigger on GET_PORT_STATUS to
2784 * stop resume signaling. Then finish the resume
2787 status = hub_port_status(hub, port1, &portstatus, &portchange);
2789 /* TRSMRCY = 10 msec */
2795 if (hub_is_superspeed(hub->hdev)) {
2796 if (portchange & USB_PORT_STAT_C_LINK_STATE)
2797 clear_port_feature(hub->hdev, port1,
2798 USB_PORT_FEAT_C_PORT_LINK_STATE);
2800 if (portchange & USB_PORT_STAT_C_SUSPEND)
2801 clear_port_feature(hub->hdev, port1,
2802 USB_PORT_FEAT_C_SUSPEND);
2806 clear_bit(port1, hub->busy_bits);
2808 if (udev->persist_enabled && hub_is_superspeed(hub->hdev))
2809 status = wait_for_ss_port_enable(udev, hub, &port1, &portchange,
2812 status = check_port_resume_type(udev,
2813 hub, port1, status, portchange, portstatus);
2815 status = finish_port_resume(udev);
2817 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2818 hub_port_logical_disconnect(hub, port1);
2820 /* Try to enable USB2 hardware LPM */
2821 if (udev->usb2_hw_lpm_capable == 1)
2822 usb_set_usb2_hardware_lpm(udev, 1);
2828 /* caller has locked udev */
2829 int usb_remote_wakeup(struct usb_device *udev)
2833 if (udev->state == USB_STATE_SUSPENDED) {
2834 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
2835 status = usb_autoresume_device(udev);
2837 /* Let the drivers do their thing, then... */
2838 usb_autosuspend_device(udev);
2844 #else /* CONFIG_USB_SUSPEND */
2846 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
2848 int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
2853 /* However we may need to do a reset-resume */
2855 int usb_port_resume(struct usb_device *udev, pm_message_t msg)
2857 struct usb_hub *hub = hdev_to_hub(udev->parent);
2858 int port1 = udev->portnum;
2860 u16 portchange, portstatus;
2862 status = hub_port_status(hub, port1, &portstatus, &portchange);
2863 status = check_port_resume_type(udev,
2864 hub, port1, status, portchange, portstatus);
2867 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2868 hub_port_logical_disconnect(hub, port1);
2869 } else if (udev->reset_resume) {
2870 dev_dbg(&udev->dev, "reset-resume\n");
2871 status = usb_reset_and_verify_device(udev);
2878 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
2880 struct usb_hub *hub = usb_get_intfdata (intf);
2881 struct usb_device *hdev = hub->hdev;
2884 /* Warn if children aren't already suspended */
2885 for (port1 = 1; port1 <= hdev->maxchild; port1++) {
2886 struct usb_device *udev;
2888 udev = hdev->children [port1-1];
2889 if (udev && udev->can_submit) {
2890 dev_warn(&intf->dev, "port %d nyet suspended\n", port1);
2891 if (PMSG_IS_AUTO(msg))
2896 dev_dbg(&intf->dev, "%s\n", __func__);
2898 /* stop khubd and related activity */
2899 hub_quiesce(hub, HUB_SUSPEND);
2903 static int hub_resume(struct usb_interface *intf)
2905 struct usb_hub *hub = usb_get_intfdata(intf);
2907 dev_dbg(&intf->dev, "%s\n", __func__);
2908 hub_activate(hub, HUB_RESUME);
2912 static int hub_reset_resume(struct usb_interface *intf)
2914 struct usb_hub *hub = usb_get_intfdata(intf);
2916 dev_dbg(&intf->dev, "%s\n", __func__);
2917 hub_activate(hub, HUB_RESET_RESUME);
2922 * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
2923 * @rhdev: struct usb_device for the root hub
2925 * The USB host controller driver calls this function when its root hub
2926 * is resumed and Vbus power has been interrupted or the controller
2927 * has been reset. The routine marks @rhdev as having lost power.
2928 * When the hub driver is resumed it will take notice and carry out
2929 * power-session recovery for all the "USB-PERSIST"-enabled child devices;
2930 * the others will be disconnected.
2932 void usb_root_hub_lost_power(struct usb_device *rhdev)
2934 dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
2935 rhdev->reset_resume = 1;
2937 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
2939 #else /* CONFIG_PM */
2941 #define hub_suspend NULL
2942 #define hub_resume NULL
2943 #define hub_reset_resume NULL
2947 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2949 * Between connect detection and reset signaling there must be a delay
2950 * of 100ms at least for debounce and power-settling. The corresponding
2951 * timer shall restart whenever the downstream port detects a disconnect.
2953 * Apparently there are some bluetooth and irda-dongles and a number of
2954 * low-speed devices for which this debounce period may last over a second.
2955 * Not covered by the spec - but easy to deal with.
2957 * This implementation uses a 1500ms total debounce timeout; if the
2958 * connection isn't stable by then it returns -ETIMEDOUT. It checks
2959 * every 25ms for transient disconnects. When the port status has been
2960 * unchanged for 100ms it returns the port status.
2962 static int hub_port_debounce(struct usb_hub *hub, int port1)
2965 int total_time, stable_time = 0;
2966 u16 portchange, portstatus;
2967 unsigned connection = 0xffff;
2969 for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2970 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2974 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2975 (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2976 stable_time += HUB_DEBOUNCE_STEP;
2977 if (stable_time >= HUB_DEBOUNCE_STABLE)
2981 connection = portstatus & USB_PORT_STAT_CONNECTION;
2984 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2985 clear_port_feature(hub->hdev, port1,
2986 USB_PORT_FEAT_C_CONNECTION);
2989 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2991 msleep(HUB_DEBOUNCE_STEP);
2994 dev_dbg (hub->intfdev,
2995 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2996 port1, total_time, stable_time, portstatus);
2998 if (stable_time < HUB_DEBOUNCE_STABLE)
3003 void usb_ep0_reinit(struct usb_device *udev)
3005 usb_disable_endpoint(udev, 0 + USB_DIR_IN, true);
3006 usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true);
3007 usb_enable_endpoint(udev, &udev->ep0, true);
3009 EXPORT_SYMBOL_GPL(usb_ep0_reinit);
3011 #define usb_sndaddr0pipe() (PIPE_CONTROL << 30)
3012 #define usb_rcvaddr0pipe() ((PIPE_CONTROL << 30) | USB_DIR_IN)
3014 static int hub_set_address(struct usb_device *udev, int devnum)
3017 struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3020 * The host controller will choose the device address,
3021 * instead of the core having chosen it earlier
3023 if (!hcd->driver->address_device && devnum <= 1)
3025 if (udev->state == USB_STATE_ADDRESS)
3027 if (udev->state != USB_STATE_DEFAULT)
3029 if (hcd->driver->address_device)
3030 retval = hcd->driver->address_device(hcd, udev);
3032 retval = usb_control_msg(udev, usb_sndaddr0pipe(),
3033 USB_REQ_SET_ADDRESS, 0, devnum, 0,
3034 NULL, 0, USB_CTRL_SET_TIMEOUT);
3036 update_devnum(udev, devnum);
3037 /* Device now using proper address. */
3038 usb_set_device_state(udev, USB_STATE_ADDRESS);
3039 usb_ep0_reinit(udev);
3044 /* Reset device, (re)assign address, get device descriptor.
3045 * Device connection must be stable, no more debouncing needed.
3046 * Returns device in USB_STATE_ADDRESS, except on error.
3048 * If this is called for an already-existing device (as part of
3049 * usb_reset_and_verify_device), the caller must own the device lock. For a
3050 * newly detected device that is not accessible through any global
3051 * pointers, it's not necessary to lock the device.
3054 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
3057 static DEFINE_MUTEX(usb_address0_mutex);
3059 struct usb_device *hdev = hub->hdev;
3060 struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
3061 int retries, operations, retval, i;
3062 unsigned delay = HUB_SHORT_RESET_TIME;
3063 enum usb_device_speed oldspeed = udev->speed;
3065 int devnum = udev->devnum;
3067 /* root hub ports have a slightly longer reset period
3068 * (from USB 2.0 spec, section 7.1.7.5)
3070 if (!hdev->parent) {
3071 delay = HUB_ROOT_RESET_TIME;
3072 if (port1 == hdev->bus->otg_port)
3073 hdev->bus->b_hnp_enable = 0;
3076 /* Some low speed devices have problems with the quick delay, so */
3077 /* be a bit pessimistic with those devices. RHbug #23670 */
3078 if (oldspeed == USB_SPEED_LOW)
3079 delay = HUB_LONG_RESET_TIME;
3081 mutex_lock(&usb_address0_mutex);
3083 /* Reset the device; full speed may morph to high speed */
3084 /* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */
3085 retval = hub_port_reset(hub, port1, udev, delay, false);
3086 if (retval < 0) /* error or disconnect */
3088 /* success, speed is known */
3092 if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
3093 dev_dbg(&udev->dev, "device reset changed speed!\n");
3096 oldspeed = udev->speed;
3098 /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
3099 * it's fixed size except for full speed devices.
3100 * For Wireless USB devices, ep0 max packet is always 512 (tho
3101 * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
3103 switch (udev->speed) {
3104 case USB_SPEED_SUPER:
3105 case USB_SPEED_WIRELESS: /* fixed at 512 */
3106 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
3108 case USB_SPEED_HIGH: /* fixed at 64 */
3109 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
3111 case USB_SPEED_FULL: /* 8, 16, 32, or 64 */
3112 /* to determine the ep0 maxpacket size, try to read
3113 * the device descriptor to get bMaxPacketSize0 and
3114 * then correct our initial guess.
3116 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
3118 case USB_SPEED_LOW: /* fixed at 8 */
3119 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(8);
3125 if (udev->speed == USB_SPEED_WIRELESS)
3126 speed = "variable speed Wireless";
3128 speed = usb_speed_string(udev->speed);
3130 if (udev->speed != USB_SPEED_SUPER)
3131 dev_info(&udev->dev,
3132 "%s %s USB device number %d using %s\n",
3133 (udev->config) ? "reset" : "new", speed,
3134 devnum, udev->bus->controller->driver->name);
3136 /* Set up TT records, if needed */
3138 udev->tt = hdev->tt;
3139 udev->ttport = hdev->ttport;
3140 } else if (udev->speed != USB_SPEED_HIGH
3141 && hdev->speed == USB_SPEED_HIGH) {
3143 dev_err(&udev->dev, "parent hub has no TT\n");
3147 udev->tt = &hub->tt;
3148 udev->ttport = port1;
3151 /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
3152 * Because device hardware and firmware is sometimes buggy in
3153 * this area, and this is how Linux has done it for ages.
3154 * Change it cautiously.
3156 * NOTE: If USE_NEW_SCHEME() is true we will start by issuing
3157 * a 64-byte GET_DESCRIPTOR request. This is what Windows does,
3158 * so it may help with some non-standards-compliant devices.
3159 * Otherwise we start with SET_ADDRESS and then try to read the
3160 * first 8 bytes of the device descriptor to get the ep0 maxpacket
3163 for (retries = 0; retries < GET_DESCRIPTOR_TRIES; (++retries, msleep(100))) {
3164 if (USE_NEW_SCHEME(retry_counter) && !(hcd->driver->flags & HCD_USB3)) {
3165 struct usb_device_descriptor *buf;
3168 #define GET_DESCRIPTOR_BUFSIZE 64
3169 buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
3175 /* Retry on all errors; some devices are flakey.
3176 * 255 is for WUSB devices, we actually need to use
3177 * 512 (WUSB1.0[4.8.1]).
3179 for (operations = 0; operations < 3; ++operations) {
3180 buf->bMaxPacketSize0 = 0;
3181 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
3182 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
3183 USB_DT_DEVICE << 8, 0,
3184 buf, GET_DESCRIPTOR_BUFSIZE,
3185 initial_descriptor_timeout);
3186 switch (buf->bMaxPacketSize0) {
3187 case 8: case 16: case 32: case 64: case 255:
3188 if (buf->bDescriptorType ==
3200 * Some devices time out if they are powered on
3201 * when already connected. They need a second
3202 * reset. But only on the first attempt,
3203 * lest we get into a time out/reset loop
3205 if (r == 0 || (r == -ETIMEDOUT && retries == 0))
3208 udev->descriptor.bMaxPacketSize0 =
3209 buf->bMaxPacketSize0;
3212 retval = hub_port_reset(hub, port1, udev, delay, false);
3213 if (retval < 0) /* error or disconnect */
3215 if (oldspeed != udev->speed) {
3217 "device reset changed speed!\n");
3223 "device descriptor read/64, error %d\n",
3228 #undef GET_DESCRIPTOR_BUFSIZE
3232 * If device is WUSB, we already assigned an
3233 * unauthorized address in the Connect Ack sequence;
3234 * authorization will assign the final address.
3236 if (udev->wusb == 0) {
3237 for (operations = 0; operations < SET_ADDRESS_TRIES; ++operations) {
3238 retval = hub_set_address(udev, devnum);
3245 "device not accepting address %d, error %d\n",
3249 if (udev->speed == USB_SPEED_SUPER) {
3250 devnum = udev->devnum;
3251 dev_info(&udev->dev,
3252 "%s SuperSpeed USB device number %d using %s\n",
3253 (udev->config) ? "reset" : "new",
3254 devnum, udev->bus->controller->driver->name);
3257 /* cope with hardware quirkiness:
3258 * - let SET_ADDRESS settle, some device hardware wants it
3259 * - read ep0 maxpacket even for high and low speed,
3262 if (USE_NEW_SCHEME(retry_counter) && !(hcd->driver->flags & HCD_USB3))
3266 retval = usb_get_device_descriptor(udev, 8);
3269 "device descriptor read/8, error %d\n",
3282 * Some superspeed devices have finished the link training process
3283 * and attached to a superspeed hub port, but the device descriptor
3284 * got from those devices show they aren't superspeed devices. Warm
3285 * reset the port attached by the devices can fix them.
3287 if ((udev->speed == USB_SPEED_SUPER) &&
3288 (le16_to_cpu(udev->descriptor.bcdUSB) < 0x0300)) {
3289 dev_err(&udev->dev, "got a wrong device descriptor, "
3290 "warm reset device\n");
3291 hub_port_reset(hub, port1, udev,
3292 HUB_BH_RESET_TIME, true);
3297 if (udev->descriptor.bMaxPacketSize0 == 0xff ||
3298 udev->speed == USB_SPEED_SUPER)
3301 i = udev->descriptor.bMaxPacketSize0;
3302 if (usb_endpoint_maxp(&udev->ep0.desc) != i) {
3303 if (udev->speed == USB_SPEED_LOW ||
3304 !(i == 8 || i == 16 || i == 32 || i == 64)) {
3305 dev_err(&udev->dev, "Invalid ep0 maxpacket: %d\n", i);
3309 if (udev->speed == USB_SPEED_FULL)
3310 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
3312 dev_warn(&udev->dev, "Using ep0 maxpacket: %d\n", i);
3313 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
3314 usb_ep0_reinit(udev);
3317 retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
3318 if (retval < (signed)sizeof(udev->descriptor)) {
3319 dev_err(&udev->dev, "device descriptor read/all, error %d\n",
3326 if (udev->wusb == 0 && le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0201) {
3327 retval = usb_get_bos_descriptor(udev);
3329 if (udev->bos->ext_cap && (USB_LPM_SUPPORT &
3330 le32_to_cpu(udev->bos->ext_cap->bmAttributes)))
3331 udev->lpm_capable = 1;
3336 /* notify HCD that we have a device connected and addressed */
3337 if (hcd->driver->update_device)
3338 hcd->driver->update_device(hcd, udev);
3341 hub_port_disable(hub, port1, 0);
3342 update_devnum(udev, devnum); /* for disconnect processing */
3344 mutex_unlock(&usb_address0_mutex);
3349 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
3351 struct usb_qualifier_descriptor *qual;
3354 qual = kmalloc (sizeof *qual, GFP_KERNEL);
3358 status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
3359 qual, sizeof *qual);
3360 if (status == sizeof *qual) {
3361 dev_info(&udev->dev, "not running at top speed; "
3362 "connect to a high speed hub\n");
3363 /* hub LEDs are probably harder to miss than syslog */
3364 if (hub->has_indicators) {
3365 hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
3366 schedule_delayed_work (&hub->leds, 0);
3373 hub_power_remaining (struct usb_hub *hub)
3375 struct usb_device *hdev = hub->hdev;
3379 if (!hub->limited_power)
3382 remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
3383 for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
3384 struct usb_device *udev = hdev->children[port1 - 1];
3390 /* Unconfigured devices may not use more than 100mA,
3391 * or 8mA for OTG ports */
3392 if (udev->actconfig)
3393 delta = udev->actconfig->desc.bMaxPower * 2;
3394 else if (port1 != udev->bus->otg_port || hdev->parent)
3398 if (delta > hub->mA_per_port)
3399 dev_warn(&udev->dev,
3400 "%dmA is over %umA budget for port %d!\n",
3401 delta, hub->mA_per_port, port1);
3404 if (remaining < 0) {
3405 dev_warn(hub->intfdev, "%dmA over power budget!\n",
3412 /* Handle physical or logical connection change events.
3413 * This routine is called when:
3414 * a port connection-change occurs;
3415 * a port enable-change occurs (often caused by EMI);
3416 * usb_reset_and_verify_device() encounters changed descriptors (as from
3417 * a firmware download)
3418 * caller already locked the hub
3420 static void hub_port_connect_change(struct usb_hub *hub, int port1,
3421 u16 portstatus, u16 portchange)
3423 struct usb_device *hdev = hub->hdev;
3424 struct device *hub_dev = hub->intfdev;
3425 struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
3426 unsigned wHubCharacteristics =
3427 le16_to_cpu(hub->descriptor->wHubCharacteristics);
3428 struct usb_device *udev;
3430 static int unreliable_port = -1;
3433 "port %d, status %04x, change %04x, %s\n",
3434 port1, portstatus, portchange, portspeed(hub, portstatus));
3436 if (hub->has_indicators) {
3437 set_port_led(hub, port1, HUB_LED_AUTO);
3438 hub->indicator[port1-1] = INDICATOR_AUTO;
3441 #ifdef CONFIG_USB_OTG
3442 /* during HNP, don't repeat the debounce */
3443 if (hdev->bus->is_b_host)
3444 portchange &= ~(USB_PORT_STAT_C_CONNECTION |
3445 USB_PORT_STAT_C_ENABLE);
3448 /* Try to resuscitate an existing device */
3449 udev = hdev->children[port1-1];
3450 if ((portstatus & USB_PORT_STAT_CONNECTION) && udev &&
3451 udev->state != USB_STATE_NOTATTACHED) {
3452 usb_lock_device(udev);
3453 if (portstatus & USB_PORT_STAT_ENABLE) {
3454 status = 0; /* Nothing to do */
3456 #ifdef CONFIG_USB_SUSPEND
3457 } else if (udev->state == USB_STATE_SUSPENDED &&
3458 udev->persist_enabled) {
3459 /* For a suspended device, treat this as a
3460 * remote wakeup event.
3462 status = usb_remote_wakeup(udev);
3466 status = -ENODEV; /* Don't resuscitate */
3468 usb_unlock_device(udev);
3471 clear_bit(port1, hub->change_bits);
3476 /* Disconnect any existing devices under this port */
3478 usb_disconnect(&hdev->children[port1-1]);
3479 clear_bit(port1, hub->change_bits);
3481 /* We can forget about a "removed" device when there's a physical
3482 * disconnect or the connect status changes.
3484 if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
3485 (portchange & USB_PORT_STAT_C_CONNECTION))
3486 clear_bit(port1, hub->removed_bits);
3488 if (portchange & (USB_PORT_STAT_C_CONNECTION |
3489 USB_PORT_STAT_C_ENABLE)) {
3490 status = hub_port_debounce(hub, port1);
3492 if (port1 != unreliable_port && printk_ratelimit())
3493 dev_err(hub_dev, "connect-debounce failed, "
3494 "port %d disabled\n", port1);
3495 portstatus &= ~USB_PORT_STAT_CONNECTION;
3496 unreliable_port = port1;
3498 portstatus = status;
3502 /* Return now if debouncing failed or nothing is connected or
3503 * the device was "removed".
3505 if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
3506 test_bit(port1, hub->removed_bits)) {
3508 /* maybe switch power back on (e.g. root hub was reset) */
3509 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
3510 && !port_is_power_on(hub, portstatus))
3511 set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
3513 if (portstatus & USB_PORT_STAT_ENABLE)
3518 for (i = 0; i < SET_CONFIG_TRIES; i++) {
3520 /* reallocate for each attempt, since references
3521 * to the previous one can escape in various ways
3523 udev = usb_alloc_dev(hdev, hdev->bus, port1);
3526 "couldn't allocate port %d usb_device\n",
3531 usb_set_device_state(udev, USB_STATE_POWERED);
3532 udev->bus_mA = hub->mA_per_port;
3533 udev->level = hdev->level + 1;
3534 udev->wusb = hub_is_wusb(hub);
3536 /* Only USB 3.0 devices are connected to SuperSpeed hubs. */
3537 if (hub_is_superspeed(hub->hdev))
3538 udev->speed = USB_SPEED_SUPER;
3540 udev->speed = USB_SPEED_UNKNOWN;
3542 choose_devnum(udev);
3543 if (udev->devnum <= 0) {
3544 status = -ENOTCONN; /* Don't retry */
3548 /* reset (non-USB 3.0 devices) and get descriptor */
3549 status = hub_port_init(hub, udev, port1, i);
3553 usb_detect_quirks(udev);
3554 if (udev->quirks & USB_QUIRK_DELAY_INIT)
3557 /* consecutive bus-powered hubs aren't reliable; they can
3558 * violate the voltage drop budget. if the new child has
3559 * a "powered" LED, users should notice we didn't enable it
3560 * (without reading syslog), even without per-port LEDs
3563 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
3564 && udev->bus_mA <= 100) {
3567 status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
3570 dev_dbg(&udev->dev, "get status %d ?\n", status);
3573 le16_to_cpus(&devstat);
3574 if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
3576 "can't connect bus-powered hub "
3578 if (hub->has_indicators) {
3579 hub->indicator[port1-1] =
3580 INDICATOR_AMBER_BLINK;
3581 schedule_delayed_work (&hub->leds, 0);
3583 status = -ENOTCONN; /* Don't retry */
3588 /* check for devices running slower than they could */
3589 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
3590 && udev->speed == USB_SPEED_FULL
3591 && highspeed_hubs != 0)
3592 check_highspeed (hub, udev, port1);
3594 /* Store the parent's children[] pointer. At this point
3595 * udev becomes globally accessible, although presumably
3596 * no one will look at it until hdev is unlocked.
3600 /* We mustn't add new devices if the parent hub has
3601 * been disconnected; we would race with the
3602 * recursively_mark_NOTATTACHED() routine.
3604 spin_lock_irq(&device_state_lock);
3605 if (hdev->state == USB_STATE_NOTATTACHED)
3608 hdev->children[port1-1] = udev;
3609 spin_unlock_irq(&device_state_lock);
3611 /* Run it through the hoops (find a driver, etc) */
3613 status = usb_new_device(udev);
3615 spin_lock_irq(&device_state_lock);
3616 hdev->children[port1-1] = NULL;
3617 spin_unlock_irq(&device_state_lock);
3624 status = hub_power_remaining(hub);
3626 dev_dbg(hub_dev, "%dmA power budget left\n", status);
3631 hub_port_disable(hub, port1, 1);
3633 usb_ep0_reinit(udev);
3634 release_devnum(udev);
3637 if ((status == -ENOTCONN) || (status == -ENOTSUPP))
3640 if (hub->hdev->parent ||
3641 !hcd->driver->port_handed_over ||
3642 !(hcd->driver->port_handed_over)(hcd, port1))
3643 dev_err(hub_dev, "unable to enumerate USB device on port %d\n",
3647 hub_port_disable(hub, port1, 1);
3648 if (hcd->driver->relinquish_port && !hub->hdev->parent)
3649 hcd->driver->relinquish_port(hcd, port1);
3652 static void hub_events(void)
3654 struct list_head *tmp;
3655 struct usb_device *hdev;
3656 struct usb_interface *intf;
3657 struct usb_hub *hub;
3658 struct device *hub_dev;
3667 * We restart the list every time to avoid a deadlock with
3668 * deleting hubs downstream from this one. This should be
3669 * safe since we delete the hub from the event list.
3670 * Not the most efficient, but avoids deadlocks.
3674 /* Grab the first entry at the beginning of the list */
3675 spin_lock_irq(&hub_event_lock);
3676 if (list_empty(&hub_event_list)) {
3677 spin_unlock_irq(&hub_event_lock);
3681 tmp = hub_event_list.next;
3684 hub = list_entry(tmp, struct usb_hub, event_list);
3685 kref_get(&hub->kref);
3688 spin_unlock_irq(&hub_event_lock);
3690 hub_dev = hub->intfdev;
3691 intf = to_usb_interface(hub_dev);
3692 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
3693 hdev->state, hub->descriptor
3694 ? hub->descriptor->bNbrPorts
3696 /* NOTE: expects max 15 ports... */
3697 (u16) hub->change_bits[0],
3698 (u16) hub->event_bits[0]);
3700 /* Lock the device, then check to see if we were
3701 * disconnected while waiting for the lock to succeed. */
3702 usb_lock_device(hdev);
3703 if (unlikely(hub->disconnected))
3704 goto loop_disconnected;
3706 /* If the hub has died, clean up after it */
3707 if (hdev->state == USB_STATE_NOTATTACHED) {
3708 hub->error = -ENODEV;
3709 hub_quiesce(hub, HUB_DISCONNECT);
3714 ret = usb_autopm_get_interface(intf);
3716 dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
3720 /* If this is an inactive hub, do nothing */
3725 dev_dbg (hub_dev, "resetting for error %d\n",
3728 ret = usb_reset_device(hdev);
3731 "error resetting hub: %d\n", ret);
3739 /* deal with port status changes */
3740 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
3741 if (test_bit(i, hub->busy_bits))
3743 connect_change = test_bit(i, hub->change_bits);
3744 if (!test_and_clear_bit(i, hub->event_bits) &&
3748 ret = hub_port_status(hub, i,
3749 &portstatus, &portchange);
3753 if (portchange & USB_PORT_STAT_C_CONNECTION) {
3754 clear_port_feature(hdev, i,
3755 USB_PORT_FEAT_C_CONNECTION);
3759 if (portchange & USB_PORT_STAT_C_ENABLE) {
3760 if (!connect_change)
3762 "port %d enable change, "
3765 clear_port_feature(hdev, i,
3766 USB_PORT_FEAT_C_ENABLE);
3769 * EM interference sometimes causes badly
3770 * shielded USB devices to be shutdown by
3771 * the hub, this hack enables them again.
3772 * Works at least with mouse driver.
3774 if (!(portstatus & USB_PORT_STAT_ENABLE)
3776 && hdev->children[i-1]) {
3779 "disabled by hub (EMI?), "
3786 if (portchange & USB_PORT_STAT_C_SUSPEND) {
3787 struct usb_device *udev;
3789 clear_port_feature(hdev, i,
3790 USB_PORT_FEAT_C_SUSPEND);
3791 udev = hdev->children[i-1];
3793 /* TRSMRCY = 10 msec */
3796 usb_lock_device(udev);
3797 ret = usb_remote_wakeup(hdev->
3799 usb_unlock_device(udev);
3804 hub_port_disable(hub, i, 1);
3807 "resume on port %d, status %d\n",
3811 if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
3815 dev_dbg(hub_dev, "over-current change on port "
3817 clear_port_feature(hdev, i,
3818 USB_PORT_FEAT_C_OVER_CURRENT);
3819 msleep(100); /* Cool down */
3820 hub_power_on(hub, true);
3821 hub_port_status(hub, i, &status, &unused);
3822 if (status & USB_PORT_STAT_OVERCURRENT)
3823 dev_err(hub_dev, "over-current "
3824 "condition on port %d\n", i);
3827 if (portchange & USB_PORT_STAT_C_RESET) {
3829 "reset change on port %d\n",
3831 clear_port_feature(hdev, i,
3832 USB_PORT_FEAT_C_RESET);
3834 if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
3835 hub_is_superspeed(hub->hdev)) {
3837 "warm reset change on port %d\n",
3839 clear_port_feature(hdev, i,
3840 USB_PORT_FEAT_C_BH_PORT_RESET);
3842 if (portchange & USB_PORT_STAT_C_LINK_STATE) {
3843 clear_port_feature(hub->hdev, i,
3844 USB_PORT_FEAT_C_PORT_LINK_STATE);
3846 if (portchange & USB_PORT_STAT_C_CONFIG_ERROR) {
3848 "config error on port %d\n",
3850 clear_port_feature(hub->hdev, i,
3851 USB_PORT_FEAT_C_PORT_CONFIG_ERROR);
3854 /* Warm reset a USB3 protocol port if it's in
3855 * SS.Inactive state.
3857 if (hub_port_warm_reset_required(hub, portstatus)) {
3859 struct usb_device *udev =
3860 hub->hdev->children[i - 1];
3862 dev_dbg(hub_dev, "warm reset port %d\n", i);
3864 !(portstatus & USB_PORT_STAT_CONNECTION) ||
3865 udev->state == USB_STATE_NOTATTACHED) {
3866 status = hub_port_reset(hub, i,
3867 NULL, HUB_BH_RESET_TIME,
3870 hub_port_disable(hub, i, 1);
3872 usb_lock_device(udev);
3873 status = usb_reset_device(udev);
3874 usb_unlock_device(udev);
3880 hub_port_connect_change(hub, i,
3881 portstatus, portchange);
3884 /* deal with hub status changes */
3885 if (test_and_clear_bit(0, hub->event_bits) == 0)
3887 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
3888 dev_err (hub_dev, "get_hub_status failed\n");
3890 if (hubchange & HUB_CHANGE_LOCAL_POWER) {
3891 dev_dbg (hub_dev, "power change\n");
3892 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
3893 if (hubstatus & HUB_STATUS_LOCAL_POWER)
3894 /* FIXME: Is this always true? */
3895 hub->limited_power = 1;
3897 hub->limited_power = 0;
3899 if (hubchange & HUB_CHANGE_OVERCURRENT) {
3903 dev_dbg(hub_dev, "over-current change\n");
3904 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
3905 msleep(500); /* Cool down */
3906 hub_power_on(hub, true);
3907 hub_hub_status(hub, &status, &unused);
3908 if (status & HUB_STATUS_OVERCURRENT)
3909 dev_err(hub_dev, "over-current "
3915 /* Balance the usb_autopm_get_interface() above */
3916 usb_autopm_put_interface_no_suspend(intf);
3918 /* Balance the usb_autopm_get_interface_no_resume() in
3919 * kick_khubd() and allow autosuspend.
3921 usb_autopm_put_interface(intf);
3923 usb_unlock_device(hdev);
3925 kref_put(&hub->kref, hub_release);
3927 } /* end while (1) */
3930 static int hub_thread(void *__unused)
3932 /* khubd needs to be freezable to avoid intefering with USB-PERSIST
3933 * port handover. Otherwise it might see that a full-speed device
3934 * was gone before the EHCI controller had handed its port over to
3935 * the companion full-speed controller.
3941 wait_event_freezable(khubd_wait,
3942 !list_empty(&hub_event_list) ||
3943 kthread_should_stop());
3944 } while (!kthread_should_stop() || !list_empty(&hub_event_list));
3946 pr_debug("%s: khubd exiting\n", usbcore_name);
3950 static const struct usb_device_id hub_id_table[] = {
3951 { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
3952 .bDeviceClass = USB_CLASS_HUB},
3953 { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
3954 .bInterfaceClass = USB_CLASS_HUB},
3955 { } /* Terminating entry */
3958 MODULE_DEVICE_TABLE (usb, hub_id_table);
3960 static struct usb_driver hub_driver = {
3963 .disconnect = hub_disconnect,
3964 .suspend = hub_suspend,
3965 .resume = hub_resume,
3966 .reset_resume = hub_reset_resume,
3967 .pre_reset = hub_pre_reset,
3968 .post_reset = hub_post_reset,
3969 .unlocked_ioctl = hub_ioctl,
3970 .id_table = hub_id_table,
3971 .supports_autosuspend = 1,
3974 int usb_hub_init(void)
3976 if (usb_register(&hub_driver) < 0) {
3977 printk(KERN_ERR "%s: can't register hub driver\n",
3982 khubd_task = kthread_run(hub_thread, NULL, "khubd");
3983 if (!IS_ERR(khubd_task))
3986 /* Fall through if kernel_thread failed */
3987 usb_deregister(&hub_driver);
3988 printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
3993 void usb_hub_cleanup(void)
3995 kthread_stop(khubd_task);
3998 * Hub resources are freed for us by usb_deregister. It calls
3999 * usb_driver_purge on every device which in turn calls that
4000 * devices disconnect function if it is using this driver.
4001 * The hub_disconnect function takes care of releasing the
4002 * individual hub resources. -greg
4004 usb_deregister(&hub_driver);
4005 } /* usb_hub_cleanup() */
4007 static int descriptors_changed(struct usb_device *udev,
4008 struct usb_device_descriptor *old_device_descriptor)
4012 unsigned serial_len = 0;
4014 unsigned old_length;
4018 if (memcmp(&udev->descriptor, old_device_descriptor,
4019 sizeof(*old_device_descriptor)) != 0)
4022 /* Since the idVendor, idProduct, and bcdDevice values in the
4023 * device descriptor haven't changed, we will assume the
4024 * Manufacturer and Product strings haven't changed either.
4025 * But the SerialNumber string could be different (e.g., a
4026 * different flash card of the same brand).
4029 serial_len = strlen(udev->serial) + 1;
4032 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
4033 old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
4034 len = max(len, old_length);
4037 buf = kmalloc(len, GFP_NOIO);
4039 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
4040 /* assume the worst */
4043 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
4044 old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
4045 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
4047 if (length != old_length) {
4048 dev_dbg(&udev->dev, "config index %d, error %d\n",
4053 if (memcmp (buf, udev->rawdescriptors[index], old_length)
4055 dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
4057 ((struct usb_config_descriptor *) buf)->
4058 bConfigurationValue);
4064 if (!changed && serial_len) {
4065 length = usb_string(udev, udev->descriptor.iSerialNumber,
4067 if (length + 1 != serial_len) {
4068 dev_dbg(&udev->dev, "serial string error %d\n",
4071 } else if (memcmp(buf, udev->serial, length) != 0) {
4072 dev_dbg(&udev->dev, "serial string changed\n");
4082 * usb_reset_and_verify_device - perform a USB port reset to reinitialize a device
4083 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
4085 * WARNING - don't use this routine to reset a composite device
4086 * (one with multiple interfaces owned by separate drivers)!
4087 * Use usb_reset_device() instead.
4089 * Do a port reset, reassign the device's address, and establish its
4090 * former operating configuration. If the reset fails, or the device's
4091 * descriptors change from their values before the reset, or the original
4092 * configuration and altsettings cannot be restored, a flag will be set
4093 * telling khubd to pretend the device has been disconnected and then
4094 * re-connected. All drivers will be unbound, and the device will be
4095 * re-enumerated and probed all over again.
4097 * Returns 0 if the reset succeeded, -ENODEV if the device has been
4098 * flagged for logical disconnection, or some other negative error code
4099 * if the reset wasn't even attempted.
4101 * The caller must own the device lock. For example, it's safe to use
4102 * this from a driver probe() routine after downloading new firmware.
4103 * For calls that might not occur during probe(), drivers should lock
4104 * the device using usb_lock_device_for_reset().
4106 * Locking exception: This routine may also be called from within an
4107 * autoresume handler. Such usage won't conflict with other tasks
4108 * holding the device lock because these tasks should always call
4109 * usb_autopm_resume_device(), thereby preventing any unwanted autoresume.
4111 static int usb_reset_and_verify_device(struct usb_device *udev)
4113 struct usb_device *parent_hdev = udev->parent;
4114 struct usb_hub *parent_hub;
4115 struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4116 struct usb_device_descriptor descriptor = udev->descriptor;
4118 int port1 = udev->portnum;
4120 if (udev->state == USB_STATE_NOTATTACHED ||
4121 udev->state == USB_STATE_SUSPENDED) {
4122 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
4128 /* this requires hcd-specific logic; see ohci_restart() */
4129 dev_dbg(&udev->dev, "%s for root hub!\n", __func__);
4132 parent_hub = hdev_to_hub(parent_hdev);
4134 /* Disable USB2 hardware LPM.
4135 * It will be re-enabled by the enumeration process.
4137 if (udev->usb2_hw_lpm_enabled == 1)
4138 usb_set_usb2_hardware_lpm(udev, 0);
4140 set_bit(port1, parent_hub->busy_bits);
4141 for (i = 0; i < SET_CONFIG_TRIES; ++i) {
4143 /* ep0 maxpacket size may change; let the HCD know about it.
4144 * Other endpoints will be handled by re-enumeration. */
4145 usb_ep0_reinit(udev);
4146 ret = hub_port_init(parent_hub, udev, port1, i);
4147 if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
4150 clear_bit(port1, parent_hub->busy_bits);
4155 /* Device might have changed firmware (DFU or similar) */
4156 if (descriptors_changed(udev, &descriptor)) {
4157 dev_info(&udev->dev, "device firmware changed\n");
4158 udev->descriptor = descriptor; /* for disconnect() calls */
4162 /* Restore the device's previous configuration */
4163 if (!udev->actconfig)
4166 mutex_lock(hcd->bandwidth_mutex);
4167 ret = usb_hcd_alloc_bandwidth(udev, udev->actconfig, NULL, NULL);
4169 dev_warn(&udev->dev,
4170 "Busted HC? Not enough HCD resources for "
4171 "old configuration.\n");
4172 mutex_unlock(hcd->bandwidth_mutex);
4175 ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
4176 USB_REQ_SET_CONFIGURATION, 0,
4177 udev->actconfig->desc.bConfigurationValue, 0,
4178 NULL, 0, USB_CTRL_SET_TIMEOUT);
4181 "can't restore configuration #%d (error=%d)\n",
4182 udev->actconfig->desc.bConfigurationValue, ret);
4183 mutex_unlock(hcd->bandwidth_mutex);
4186 mutex_unlock(hcd->bandwidth_mutex);
4187 usb_set_device_state(udev, USB_STATE_CONFIGURED);
4189 /* Put interfaces back into the same altsettings as before.
4190 * Don't bother to send the Set-Interface request for interfaces
4191 * that were already in altsetting 0; besides being unnecessary,
4192 * many devices can't handle it. Instead just reset the host-side
4195 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
4196 struct usb_host_config *config = udev->actconfig;
4197 struct usb_interface *intf = config->interface[i];
4198 struct usb_interface_descriptor *desc;
4200 desc = &intf->cur_altsetting->desc;
4201 if (desc->bAlternateSetting == 0) {
4202 usb_disable_interface(udev, intf, true);
4203 usb_enable_interface(udev, intf, true);
4206 /* Let the bandwidth allocation function know that this
4207 * device has been reset, and it will have to use
4208 * alternate setting 0 as the current alternate setting.
4210 intf->resetting_device = 1;
4211 ret = usb_set_interface(udev, desc->bInterfaceNumber,
4212 desc->bAlternateSetting);
4213 intf->resetting_device = 0;
4216 dev_err(&udev->dev, "failed to restore interface %d "
4217 "altsetting %d (error=%d)\n",
4218 desc->bInterfaceNumber,
4219 desc->bAlternateSetting,
4229 hub_port_logical_disconnect(parent_hub, port1);
4234 * usb_reset_device - warn interface drivers and perform a USB port reset
4235 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
4237 * Warns all drivers bound to registered interfaces (using their pre_reset
4238 * method), performs the port reset, and then lets the drivers know that
4239 * the reset is over (using their post_reset method).
4241 * Return value is the same as for usb_reset_and_verify_device().
4243 * The caller must own the device lock. For example, it's safe to use
4244 * this from a driver probe() routine after downloading new firmware.
4245 * For calls that might not occur during probe(), drivers should lock
4246 * the device using usb_lock_device_for_reset().
4248 * If an interface is currently being probed or disconnected, we assume
4249 * its driver knows how to handle resets. For all other interfaces,
4250 * if the driver doesn't have pre_reset and post_reset methods then
4251 * we attempt to unbind it and rebind afterward.
4253 int usb_reset_device(struct usb_device *udev)
4257 struct usb_host_config *config = udev->actconfig;
4259 if (udev->state == USB_STATE_NOTATTACHED ||
4260 udev->state == USB_STATE_SUSPENDED) {
4261 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
4266 /* Prevent autosuspend during the reset */
4267 usb_autoresume_device(udev);
4270 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
4271 struct usb_interface *cintf = config->interface[i];
4272 struct usb_driver *drv;
4275 if (cintf->dev.driver) {
4276 drv = to_usb_driver(cintf->dev.driver);
4277 if (drv->pre_reset && drv->post_reset)
4278 unbind = (drv->pre_reset)(cintf);
4279 else if (cintf->condition ==
4280 USB_INTERFACE_BOUND)
4283 usb_forced_unbind_intf(cintf);
4288 ret = usb_reset_and_verify_device(udev);
4291 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
4292 struct usb_interface *cintf = config->interface[i];
4293 struct usb_driver *drv;
4294 int rebind = cintf->needs_binding;
4296 if (!rebind && cintf->dev.driver) {
4297 drv = to_usb_driver(cintf->dev.driver);
4298 if (drv->post_reset)
4299 rebind = (drv->post_reset)(cintf);
4300 else if (cintf->condition ==
4301 USB_INTERFACE_BOUND)
4304 if (ret == 0 && rebind)
4305 usb_rebind_intf(cintf);
4309 usb_autosuspend_device(udev);
4312 EXPORT_SYMBOL_GPL(usb_reset_device);
4316 * usb_queue_reset_device - Reset a USB device from an atomic context
4317 * @iface: USB interface belonging to the device to reset
4319 * This function can be used to reset a USB device from an atomic
4320 * context, where usb_reset_device() won't work (as it blocks).
4322 * Doing a reset via this method is functionally equivalent to calling
4323 * usb_reset_device(), except for the fact that it is delayed to a
4324 * workqueue. This means that any drivers bound to other interfaces
4325 * might be unbound, as well as users from usbfs in user space.
4329 * - Scheduling two resets at the same time from two different drivers
4330 * attached to two different interfaces of the same device is
4331 * possible; depending on how the driver attached to each interface
4332 * handles ->pre_reset(), the second reset might happen or not.
4334 * - If a driver is unbound and it had a pending reset, the reset will
4337 * - This function can be called during .probe() or .disconnect()
4338 * times. On return from .disconnect(), any pending resets will be
4341 * There is no no need to lock/unlock the @reset_ws as schedule_work()
4344 * NOTE: We don't do any reference count tracking because it is not
4345 * needed. The lifecycle of the work_struct is tied to the
4346 * usb_interface. Before destroying the interface we cancel the
4347 * work_struct, so the fact that work_struct is queued and or
4348 * running means the interface (and thus, the device) exist and
4351 void usb_queue_reset_device(struct usb_interface *iface)
4353 schedule_work(&iface->reset_ws);
4355 EXPORT_SYMBOL_GPL(usb_queue_reset_device);