USB: prevent buggy hubs from crashing the USB stack
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / usb / core / hub.c
blob0b5561e936c0c976b27c59c3be03f2a243de3b5e
1 /*
2 * USB hub driver.
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)
9 */
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/pm_runtime.h>
29 #include <asm/uaccess.h>
30 #include <asm/byteorder.h>
32 #include "usb.h"
34 /* if we are in debug mode, always announce new devices */
35 #ifdef DEBUG
36 #ifndef CONFIG_USB_ANNOUNCE_NEW_DEVICES
37 #define CONFIG_USB_ANNOUNCE_NEW_DEVICES
38 #endif
39 #endif
41 struct usb_hub {
42 struct device *intfdev; /* the "interface" device */
43 struct usb_device *hdev;
44 struct kref kref;
45 struct urb *urb; /* for interrupt polling pipe */
47 /* buffer for urb ... with extra space in case of babble */
48 char (*buffer)[8];
49 union {
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
61 status change */
62 unsigned long busy_bits[1]; /* ports being reset or
63 resumed */
64 unsigned long removed_bits[1]; /* ports with a "removed"
65 device present */
66 #if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
67 #error event_bits[] is too short!
68 #endif
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;
76 unsigned quiescing: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;
83 void **port_owners;
87 /* Protect struct usb_device->state and ->children members
88 * Note: Both are also protected by ->dev.sem, except that ->state can
89 * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
90 static DEFINE_SPINLOCK(device_state_lock);
92 /* khubd's worklist and its lock */
93 static DEFINE_SPINLOCK(hub_event_lock);
94 static LIST_HEAD(hub_event_list); /* List of hubs needing servicing */
96 /* Wakes up khubd */
97 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
99 static struct task_struct *khubd_task;
101 /* cycle leds on hubs that aren't blinking for attention */
102 static int blinkenlights = 0;
103 module_param (blinkenlights, bool, S_IRUGO);
104 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
107 * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
108 * 10 seconds to send reply for the initial 64-byte descriptor request.
110 /* define initial 64-byte descriptor request timeout in milliseconds */
111 static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
112 module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
113 MODULE_PARM_DESC(initial_descriptor_timeout,
114 "initial 64-byte descriptor request timeout in milliseconds "
115 "(default 5000 - 5.0 seconds)");
118 * As of 2.6.10 we introduce a new USB device initialization scheme which
119 * closely resembles the way Windows works. Hopefully it will be compatible
120 * with a wider range of devices than the old scheme. However some previously
121 * working devices may start giving rise to "device not accepting address"
122 * errors; if that happens the user can try the old scheme by adjusting the
123 * following module parameters.
125 * For maximum flexibility there are two boolean parameters to control the
126 * hub driver's behavior. On the first initialization attempt, if the
127 * "old_scheme_first" parameter is set then the old scheme will be used,
128 * otherwise the new scheme is used. If that fails and "use_both_schemes"
129 * is set, then the driver will make another attempt, using the other scheme.
131 static int old_scheme_first = 0;
132 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
133 MODULE_PARM_DESC(old_scheme_first,
134 "start with the old device initialization scheme");
136 static int use_both_schemes = 1;
137 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
138 MODULE_PARM_DESC(use_both_schemes,
139 "try the other device initialization scheme if the "
140 "first one fails");
142 /* Mutual exclusion for EHCI CF initialization. This interferes with
143 * port reset on some companion controllers.
145 DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
146 EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
148 #define HUB_DEBOUNCE_TIMEOUT 1500
149 #define HUB_DEBOUNCE_STEP 25
150 #define HUB_DEBOUNCE_STABLE 100
153 static int usb_reset_and_verify_device(struct usb_device *udev);
155 static inline char *portspeed(int portstatus)
157 if (portstatus & USB_PORT_STAT_HIGH_SPEED)
158 return "480 Mb/s";
159 else if (portstatus & USB_PORT_STAT_LOW_SPEED)
160 return "1.5 Mb/s";
161 else if (portstatus & USB_PORT_STAT_SUPER_SPEED)
162 return "5.0 Gb/s";
163 else
164 return "12 Mb/s";
167 /* Note that hdev or one of its children must be locked! */
168 static struct usb_hub *hdev_to_hub(struct usb_device *hdev)
170 if (!hdev || !hdev->actconfig)
171 return NULL;
172 return usb_get_intfdata(hdev->actconfig->interface[0]);
175 /* USB 2.0 spec Section 11.24.4.5 */
176 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
178 int i, ret;
180 for (i = 0; i < 3; i++) {
181 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
182 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
183 USB_DT_HUB << 8, 0, data, size,
184 USB_CTRL_GET_TIMEOUT);
185 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
186 return ret;
188 return -EINVAL;
192 * USB 2.0 spec Section 11.24.2.1
194 static int clear_hub_feature(struct usb_device *hdev, int feature)
196 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
197 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
201 * USB 2.0 spec Section 11.24.2.2
203 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
205 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
206 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
207 NULL, 0, 1000);
211 * USB 2.0 spec Section 11.24.2.13
213 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
215 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
216 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
217 NULL, 0, 1000);
221 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
222 * for info about using port indicators
224 static void set_port_led(
225 struct usb_hub *hub,
226 int port1,
227 int selector
230 int status = set_port_feature(hub->hdev, (selector << 8) | port1,
231 USB_PORT_FEAT_INDICATOR);
232 if (status < 0)
233 dev_dbg (hub->intfdev,
234 "port %d indicator %s status %d\n",
235 port1,
236 ({ char *s; switch (selector) {
237 case HUB_LED_AMBER: s = "amber"; break;
238 case HUB_LED_GREEN: s = "green"; break;
239 case HUB_LED_OFF: s = "off"; break;
240 case HUB_LED_AUTO: s = "auto"; break;
241 default: s = "??"; break;
242 }; s; }),
243 status);
246 #define LED_CYCLE_PERIOD ((2*HZ)/3)
248 static void led_work (struct work_struct *work)
250 struct usb_hub *hub =
251 container_of(work, struct usb_hub, leds.work);
252 struct usb_device *hdev = hub->hdev;
253 unsigned i;
254 unsigned changed = 0;
255 int cursor = -1;
257 if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
258 return;
260 for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
261 unsigned selector, mode;
263 /* 30%-50% duty cycle */
265 switch (hub->indicator[i]) {
266 /* cycle marker */
267 case INDICATOR_CYCLE:
268 cursor = i;
269 selector = HUB_LED_AUTO;
270 mode = INDICATOR_AUTO;
271 break;
272 /* blinking green = sw attention */
273 case INDICATOR_GREEN_BLINK:
274 selector = HUB_LED_GREEN;
275 mode = INDICATOR_GREEN_BLINK_OFF;
276 break;
277 case INDICATOR_GREEN_BLINK_OFF:
278 selector = HUB_LED_OFF;
279 mode = INDICATOR_GREEN_BLINK;
280 break;
281 /* blinking amber = hw attention */
282 case INDICATOR_AMBER_BLINK:
283 selector = HUB_LED_AMBER;
284 mode = INDICATOR_AMBER_BLINK_OFF;
285 break;
286 case INDICATOR_AMBER_BLINK_OFF:
287 selector = HUB_LED_OFF;
288 mode = INDICATOR_AMBER_BLINK;
289 break;
290 /* blink green/amber = reserved */
291 case INDICATOR_ALT_BLINK:
292 selector = HUB_LED_GREEN;
293 mode = INDICATOR_ALT_BLINK_OFF;
294 break;
295 case INDICATOR_ALT_BLINK_OFF:
296 selector = HUB_LED_AMBER;
297 mode = INDICATOR_ALT_BLINK;
298 break;
299 default:
300 continue;
302 if (selector != HUB_LED_AUTO)
303 changed = 1;
304 set_port_led(hub, i + 1, selector);
305 hub->indicator[i] = mode;
307 if (!changed && blinkenlights) {
308 cursor++;
309 cursor %= hub->descriptor->bNbrPorts;
310 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
311 hub->indicator[cursor] = INDICATOR_CYCLE;
312 changed++;
314 if (changed)
315 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
318 /* use a short timeout for hub/port status fetches */
319 #define USB_STS_TIMEOUT 1000
320 #define USB_STS_RETRIES 5
323 * USB 2.0 spec Section 11.24.2.6
325 static int get_hub_status(struct usb_device *hdev,
326 struct usb_hub_status *data)
328 int i, status = -ETIMEDOUT;
330 for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
331 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
332 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
333 data, sizeof(*data), USB_STS_TIMEOUT);
335 return status;
339 * USB 2.0 spec Section 11.24.2.7
341 static int get_port_status(struct usb_device *hdev, int port1,
342 struct usb_port_status *data)
344 int i, status = -ETIMEDOUT;
346 for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
347 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
348 USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
349 data, sizeof(*data), USB_STS_TIMEOUT);
351 return status;
354 static int hub_port_status(struct usb_hub *hub, int port1,
355 u16 *status, u16 *change)
357 int ret;
359 mutex_lock(&hub->status_mutex);
360 ret = get_port_status(hub->hdev, port1, &hub->status->port);
361 if (ret < 4) {
362 dev_err(hub->intfdev,
363 "%s failed (err = %d)\n", __func__, ret);
364 if (ret >= 0)
365 ret = -EIO;
366 } else {
367 *status = le16_to_cpu(hub->status->port.wPortStatus);
368 *change = le16_to_cpu(hub->status->port.wPortChange);
369 ret = 0;
371 mutex_unlock(&hub->status_mutex);
372 return ret;
375 static void kick_khubd(struct usb_hub *hub)
377 unsigned long flags;
379 spin_lock_irqsave(&hub_event_lock, flags);
380 if (!hub->disconnected && list_empty(&hub->event_list)) {
381 list_add_tail(&hub->event_list, &hub_event_list);
383 /* Suppress autosuspend until khubd runs */
384 usb_autopm_get_interface_no_resume(
385 to_usb_interface(hub->intfdev));
386 wake_up(&khubd_wait);
388 spin_unlock_irqrestore(&hub_event_lock, flags);
391 void usb_kick_khubd(struct usb_device *hdev)
393 struct usb_hub *hub = hdev_to_hub(hdev);
395 if (hub)
396 kick_khubd(hub);
400 /* completion function, fires on port status changes and various faults */
401 static void hub_irq(struct urb *urb)
403 struct usb_hub *hub = urb->context;
404 int status = urb->status;
405 unsigned i;
406 unsigned long bits;
408 switch (status) {
409 case -ENOENT: /* synchronous unlink */
410 case -ECONNRESET: /* async unlink */
411 case -ESHUTDOWN: /* hardware going away */
412 return;
414 default: /* presumably an error */
415 /* Cause a hub reset after 10 consecutive errors */
416 dev_dbg (hub->intfdev, "transfer --> %d\n", status);
417 if ((++hub->nerrors < 10) || hub->error)
418 goto resubmit;
419 hub->error = status;
420 /* FALL THROUGH */
422 /* let khubd handle things */
423 case 0: /* we got data: port status changed */
424 bits = 0;
425 for (i = 0; i < urb->actual_length; ++i)
426 bits |= ((unsigned long) ((*hub->buffer)[i]))
427 << (i*8);
428 hub->event_bits[0] = bits;
429 break;
432 hub->nerrors = 0;
434 /* Something happened, let khubd figure it out */
435 kick_khubd(hub);
437 resubmit:
438 if (hub->quiescing)
439 return;
441 if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
442 && status != -ENODEV && status != -EPERM)
443 dev_err (hub->intfdev, "resubmit --> %d\n", status);
446 /* USB 2.0 spec Section 11.24.2.3 */
447 static inline int
448 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
450 return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
451 HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
452 tt, NULL, 0, 1000);
456 * enumeration blocks khubd for a long time. we use keventd instead, since
457 * long blocking there is the exception, not the rule. accordingly, HCDs
458 * talking to TTs must queue control transfers (not just bulk and iso), so
459 * both can talk to the same hub concurrently.
461 static void hub_tt_work(struct work_struct *work)
463 struct usb_hub *hub =
464 container_of(work, struct usb_hub, tt.clear_work);
465 unsigned long flags;
466 int limit = 100;
468 spin_lock_irqsave (&hub->tt.lock, flags);
469 while (--limit && !list_empty (&hub->tt.clear_list)) {
470 struct list_head *next;
471 struct usb_tt_clear *clear;
472 struct usb_device *hdev = hub->hdev;
473 const struct hc_driver *drv;
474 int status;
476 next = hub->tt.clear_list.next;
477 clear = list_entry (next, struct usb_tt_clear, clear_list);
478 list_del (&clear->clear_list);
480 /* drop lock so HCD can concurrently report other TT errors */
481 spin_unlock_irqrestore (&hub->tt.lock, flags);
482 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
483 if (status)
484 dev_err (&hdev->dev,
485 "clear tt %d (%04x) error %d\n",
486 clear->tt, clear->devinfo, status);
488 /* Tell the HCD, even if the operation failed */
489 drv = clear->hcd->driver;
490 if (drv->clear_tt_buffer_complete)
491 (drv->clear_tt_buffer_complete)(clear->hcd, clear->ep);
493 kfree(clear);
494 spin_lock_irqsave(&hub->tt.lock, flags);
496 spin_unlock_irqrestore (&hub->tt.lock, flags);
500 * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
501 * @urb: an URB associated with the failed or incomplete split transaction
503 * High speed HCDs use this to tell the hub driver that some split control or
504 * bulk transaction failed in a way that requires clearing internal state of
505 * a transaction translator. This is normally detected (and reported) from
506 * interrupt context.
508 * It may not be possible for that hub to handle additional full (or low)
509 * speed transactions until that state is fully cleared out.
511 int usb_hub_clear_tt_buffer(struct urb *urb)
513 struct usb_device *udev = urb->dev;
514 int pipe = urb->pipe;
515 struct usb_tt *tt = udev->tt;
516 unsigned long flags;
517 struct usb_tt_clear *clear;
519 /* we've got to cope with an arbitrary number of pending TT clears,
520 * since each TT has "at least two" buffers that can need it (and
521 * there can be many TTs per hub). even if they're uncommon.
523 if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) {
524 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
525 /* FIXME recover somehow ... RESET_TT? */
526 return -ENOMEM;
529 /* info that CLEAR_TT_BUFFER needs */
530 clear->tt = tt->multi ? udev->ttport : 1;
531 clear->devinfo = usb_pipeendpoint (pipe);
532 clear->devinfo |= udev->devnum << 4;
533 clear->devinfo |= usb_pipecontrol (pipe)
534 ? (USB_ENDPOINT_XFER_CONTROL << 11)
535 : (USB_ENDPOINT_XFER_BULK << 11);
536 if (usb_pipein (pipe))
537 clear->devinfo |= 1 << 15;
539 /* info for completion callback */
540 clear->hcd = bus_to_hcd(udev->bus);
541 clear->ep = urb->ep;
543 /* tell keventd to clear state for this TT */
544 spin_lock_irqsave (&tt->lock, flags);
545 list_add_tail (&clear->clear_list, &tt->clear_list);
546 schedule_work(&tt->clear_work);
547 spin_unlock_irqrestore (&tt->lock, flags);
548 return 0;
550 EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer);
552 /* If do_delay is false, return the number of milliseconds the caller
553 * needs to delay.
555 static unsigned hub_power_on(struct usb_hub *hub, bool do_delay)
557 int port1;
558 unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
559 unsigned delay;
560 u16 wHubCharacteristics =
561 le16_to_cpu(hub->descriptor->wHubCharacteristics);
563 /* Enable power on each port. Some hubs have reserved values
564 * of LPSM (> 2) in their descriptors, even though they are
565 * USB 2.0 hubs. Some hubs do not implement port-power switching
566 * but only emulate it. In all cases, the ports won't work
567 * unless we send these messages to the hub.
569 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
570 dev_dbg(hub->intfdev, "enabling power on all ports\n");
571 else
572 dev_dbg(hub->intfdev, "trying to enable port power on "
573 "non-switchable hub\n");
574 for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
575 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
577 /* Wait at least 100 msec for power to become stable */
578 delay = max(pgood_delay, (unsigned) 100);
579 if (do_delay)
580 msleep(delay);
581 return delay;
584 static int hub_hub_status(struct usb_hub *hub,
585 u16 *status, u16 *change)
587 int ret;
589 mutex_lock(&hub->status_mutex);
590 ret = get_hub_status(hub->hdev, &hub->status->hub);
591 if (ret < 0)
592 dev_err (hub->intfdev,
593 "%s failed (err = %d)\n", __func__, ret);
594 else {
595 *status = le16_to_cpu(hub->status->hub.wHubStatus);
596 *change = le16_to_cpu(hub->status->hub.wHubChange);
597 ret = 0;
599 mutex_unlock(&hub->status_mutex);
600 return ret;
603 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
605 struct usb_device *hdev = hub->hdev;
606 int ret = 0;
608 if (hdev->children[port1-1] && set_state)
609 usb_set_device_state(hdev->children[port1-1],
610 USB_STATE_NOTATTACHED);
611 if (!hub->error)
612 ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
613 if (ret)
614 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
615 port1, ret);
616 return ret;
620 * Disable a port and mark a logical connnect-change event, so that some
621 * time later khubd will disconnect() any existing usb_device on the port
622 * and will re-enumerate if there actually is a device attached.
624 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
626 dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
627 hub_port_disable(hub, port1, 1);
629 /* FIXME let caller ask to power down the port:
630 * - some devices won't enumerate without a VBUS power cycle
631 * - SRP saves power that way
632 * - ... new call, TBD ...
633 * That's easy if this hub can switch power per-port, and
634 * khubd reactivates the port later (timer, SRP, etc).
635 * Powerdown must be optional, because of reset/DFU.
638 set_bit(port1, hub->change_bits);
639 kick_khubd(hub);
643 * usb_remove_device - disable a device's port on its parent hub
644 * @udev: device to be disabled and removed
645 * Context: @udev locked, must be able to sleep.
647 * After @udev's port has been disabled, khubd is notified and it will
648 * see that the device has been disconnected. When the device is
649 * physically unplugged and something is plugged in, the events will
650 * be received and processed normally.
652 int usb_remove_device(struct usb_device *udev)
654 struct usb_hub *hub;
655 struct usb_interface *intf;
657 if (!udev->parent) /* Can't remove a root hub */
658 return -EINVAL;
659 hub = hdev_to_hub(udev->parent);
660 intf = to_usb_interface(hub->intfdev);
662 usb_autopm_get_interface(intf);
663 set_bit(udev->portnum, hub->removed_bits);
664 hub_port_logical_disconnect(hub, udev->portnum);
665 usb_autopm_put_interface(intf);
666 return 0;
669 enum hub_activation_type {
670 HUB_INIT, HUB_INIT2, HUB_INIT3, /* INITs must come first */
671 HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
674 static void hub_init_func2(struct work_struct *ws);
675 static void hub_init_func3(struct work_struct *ws);
677 static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
679 struct usb_device *hdev = hub->hdev;
680 int port1;
681 int status;
682 bool need_debounce_delay = false;
683 unsigned delay;
685 /* Continue a partial initialization */
686 if (type == HUB_INIT2)
687 goto init2;
688 if (type == HUB_INIT3)
689 goto init3;
691 /* After a resume, port power should still be on.
692 * For any other type of activation, turn it on.
694 if (type != HUB_RESUME) {
696 /* Speed up system boot by using a delayed_work for the
697 * hub's initial power-up delays. This is pretty awkward
698 * and the implementation looks like a home-brewed sort of
699 * setjmp/longjmp, but it saves at least 100 ms for each
700 * root hub (assuming usbcore is compiled into the kernel
701 * rather than as a module). It adds up.
703 * This can't be done for HUB_RESUME or HUB_RESET_RESUME
704 * because for those activation types the ports have to be
705 * operational when we return. In theory this could be done
706 * for HUB_POST_RESET, but it's easier not to.
708 if (type == HUB_INIT) {
709 delay = hub_power_on(hub, false);
710 PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func2);
711 schedule_delayed_work(&hub->init_work,
712 msecs_to_jiffies(delay));
714 /* Suppress autosuspend until init is done */
715 usb_autopm_get_interface_no_resume(
716 to_usb_interface(hub->intfdev));
717 return; /* Continues at init2: below */
718 } else {
719 hub_power_on(hub, true);
722 init2:
724 /* Check each port and set hub->change_bits to let khubd know
725 * which ports need attention.
727 for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
728 struct usb_device *udev = hdev->children[port1-1];
729 u16 portstatus, portchange;
731 portstatus = portchange = 0;
732 status = hub_port_status(hub, port1, &portstatus, &portchange);
733 if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
734 dev_dbg(hub->intfdev,
735 "port %d: status %04x change %04x\n",
736 port1, portstatus, portchange);
738 /* After anything other than HUB_RESUME (i.e., initialization
739 * or any sort of reset), every port should be disabled.
740 * Unconnected ports should likewise be disabled (paranoia),
741 * and so should ports for which we have no usb_device.
743 if ((portstatus & USB_PORT_STAT_ENABLE) && (
744 type != HUB_RESUME ||
745 !(portstatus & USB_PORT_STAT_CONNECTION) ||
746 !udev ||
747 udev->state == USB_STATE_NOTATTACHED)) {
749 * USB3 protocol ports will automatically transition
750 * to Enabled state when detect an USB3.0 device attach.
751 * Do not disable USB3 protocol ports.
752 * FIXME: USB3 root hub and external hubs are treated
753 * differently here.
755 if (hdev->descriptor.bDeviceProtocol != 3 ||
756 (!hdev->parent &&
757 !(portstatus & USB_PORT_STAT_SUPER_SPEED))) {
758 clear_port_feature(hdev, port1,
759 USB_PORT_FEAT_ENABLE);
760 portstatus &= ~USB_PORT_STAT_ENABLE;
761 } else {
762 /* Pretend that power was lost for USB3 devs */
763 portstatus &= ~USB_PORT_STAT_ENABLE;
767 /* Clear status-change flags; we'll debounce later */
768 if (portchange & USB_PORT_STAT_C_CONNECTION) {
769 need_debounce_delay = true;
770 clear_port_feature(hub->hdev, port1,
771 USB_PORT_FEAT_C_CONNECTION);
773 if (portchange & USB_PORT_STAT_C_ENABLE) {
774 need_debounce_delay = true;
775 clear_port_feature(hub->hdev, port1,
776 USB_PORT_FEAT_C_ENABLE);
779 /* We can forget about a "removed" device when there's a
780 * physical disconnect or the connect status changes.
782 if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
783 (portchange & USB_PORT_STAT_C_CONNECTION))
784 clear_bit(port1, hub->removed_bits);
786 if (!udev || udev->state == USB_STATE_NOTATTACHED) {
787 /* Tell khubd to disconnect the device or
788 * check for a new connection
790 if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
791 set_bit(port1, hub->change_bits);
793 } else if (portstatus & USB_PORT_STAT_ENABLE) {
794 /* The power session apparently survived the resume.
795 * If there was an overcurrent or suspend change
796 * (i.e., remote wakeup request), have khubd
797 * take care of it.
799 if (portchange)
800 set_bit(port1, hub->change_bits);
802 } else if (udev->persist_enabled) {
803 #ifdef CONFIG_PM
804 udev->reset_resume = 1;
805 #endif
806 set_bit(port1, hub->change_bits);
808 } else {
809 /* The power session is gone; tell khubd */
810 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
811 set_bit(port1, hub->change_bits);
815 /* If no port-status-change flags were set, we don't need any
816 * debouncing. If flags were set we can try to debounce the
817 * ports all at once right now, instead of letting khubd do them
818 * one at a time later on.
820 * If any port-status changes do occur during this delay, khubd
821 * will see them later and handle them normally.
823 if (need_debounce_delay) {
824 delay = HUB_DEBOUNCE_STABLE;
826 /* Don't do a long sleep inside a workqueue routine */
827 if (type == HUB_INIT2) {
828 PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func3);
829 schedule_delayed_work(&hub->init_work,
830 msecs_to_jiffies(delay));
831 return; /* Continues at init3: below */
832 } else {
833 msleep(delay);
836 init3:
837 hub->quiescing = 0;
839 status = usb_submit_urb(hub->urb, GFP_NOIO);
840 if (status < 0)
841 dev_err(hub->intfdev, "activate --> %d\n", status);
842 if (hub->has_indicators && blinkenlights)
843 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
845 /* Scan all ports that need attention */
846 kick_khubd(hub);
848 /* Allow autosuspend if it was suppressed */
849 if (type <= HUB_INIT3)
850 usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
853 /* Implement the continuations for the delays above */
854 static void hub_init_func2(struct work_struct *ws)
856 struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
858 hub_activate(hub, HUB_INIT2);
861 static void hub_init_func3(struct work_struct *ws)
863 struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
865 hub_activate(hub, HUB_INIT3);
868 enum hub_quiescing_type {
869 HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
872 static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
874 struct usb_device *hdev = hub->hdev;
875 int i;
877 cancel_delayed_work_sync(&hub->init_work);
879 /* khubd and related activity won't re-trigger */
880 hub->quiescing = 1;
882 if (type != HUB_SUSPEND) {
883 /* Disconnect all the children */
884 for (i = 0; i < hdev->maxchild; ++i) {
885 if (hdev->children[i])
886 usb_disconnect(&hdev->children[i]);
890 /* Stop khubd and related activity */
891 usb_kill_urb(hub->urb);
892 if (hub->has_indicators)
893 cancel_delayed_work_sync(&hub->leds);
894 if (hub->tt.hub)
895 cancel_work_sync(&hub->tt.clear_work);
898 /* caller has locked the hub device */
899 static int hub_pre_reset(struct usb_interface *intf)
901 struct usb_hub *hub = usb_get_intfdata(intf);
903 hub_quiesce(hub, HUB_PRE_RESET);
904 return 0;
907 /* caller has locked the hub device */
908 static int hub_post_reset(struct usb_interface *intf)
910 struct usb_hub *hub = usb_get_intfdata(intf);
912 hub_activate(hub, HUB_POST_RESET);
913 return 0;
916 static int hub_configure(struct usb_hub *hub,
917 struct usb_endpoint_descriptor *endpoint)
919 struct usb_hcd *hcd;
920 struct usb_device *hdev = hub->hdev;
921 struct device *hub_dev = hub->intfdev;
922 u16 hubstatus, hubchange;
923 u16 wHubCharacteristics;
924 unsigned int pipe;
925 int maxp, ret;
926 char *message = "out of memory";
928 hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
929 if (!hub->buffer) {
930 ret = -ENOMEM;
931 goto fail;
934 hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
935 if (!hub->status) {
936 ret = -ENOMEM;
937 goto fail;
939 mutex_init(&hub->status_mutex);
941 hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
942 if (!hub->descriptor) {
943 ret = -ENOMEM;
944 goto fail;
947 /* Request the entire hub descriptor.
948 * hub->descriptor can handle USB_MAXCHILDREN ports,
949 * but the hub can/will return fewer bytes here.
951 ret = get_hub_descriptor(hdev, hub->descriptor,
952 sizeof(*hub->descriptor));
953 if (ret < 0) {
954 message = "can't read hub descriptor";
955 goto fail;
956 } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
957 message = "hub has too many ports!";
958 ret = -ENODEV;
959 goto fail;
962 hdev->maxchild = hub->descriptor->bNbrPorts;
963 dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
964 (hdev->maxchild == 1) ? "" : "s");
966 hub->port_owners = kzalloc(hdev->maxchild * sizeof(void *), GFP_KERNEL);
967 if (!hub->port_owners) {
968 ret = -ENOMEM;
969 goto fail;
972 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
974 if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
975 int i;
976 char portstr [USB_MAXCHILDREN + 1];
978 for (i = 0; i < hdev->maxchild; i++)
979 portstr[i] = hub->descriptor->DeviceRemovable
980 [((i + 1) / 8)] & (1 << ((i + 1) % 8))
981 ? 'F' : 'R';
982 portstr[hdev->maxchild] = 0;
983 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
984 } else
985 dev_dbg(hub_dev, "standalone hub\n");
987 switch (wHubCharacteristics & HUB_CHAR_LPSM) {
988 case 0x00:
989 dev_dbg(hub_dev, "ganged power switching\n");
990 break;
991 case 0x01:
992 dev_dbg(hub_dev, "individual port power switching\n");
993 break;
994 case 0x02:
995 case 0x03:
996 dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
997 break;
1000 switch (wHubCharacteristics & HUB_CHAR_OCPM) {
1001 case 0x00:
1002 dev_dbg(hub_dev, "global over-current protection\n");
1003 break;
1004 case 0x08:
1005 dev_dbg(hub_dev, "individual port over-current protection\n");
1006 break;
1007 case 0x10:
1008 case 0x18:
1009 dev_dbg(hub_dev, "no over-current protection\n");
1010 break;
1013 spin_lock_init (&hub->tt.lock);
1014 INIT_LIST_HEAD (&hub->tt.clear_list);
1015 INIT_WORK(&hub->tt.clear_work, hub_tt_work);
1016 switch (hdev->descriptor.bDeviceProtocol) {
1017 case 0:
1018 break;
1019 case 1:
1020 dev_dbg(hub_dev, "Single TT\n");
1021 hub->tt.hub = hdev;
1022 break;
1023 case 2:
1024 ret = usb_set_interface(hdev, 0, 1);
1025 if (ret == 0) {
1026 dev_dbg(hub_dev, "TT per port\n");
1027 hub->tt.multi = 1;
1028 } else
1029 dev_err(hub_dev, "Using single TT (err %d)\n",
1030 ret);
1031 hub->tt.hub = hdev;
1032 break;
1033 case 3:
1034 /* USB 3.0 hubs don't have a TT */
1035 break;
1036 default:
1037 dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
1038 hdev->descriptor.bDeviceProtocol);
1039 break;
1042 /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
1043 switch (wHubCharacteristics & HUB_CHAR_TTTT) {
1044 case HUB_TTTT_8_BITS:
1045 if (hdev->descriptor.bDeviceProtocol != 0) {
1046 hub->tt.think_time = 666;
1047 dev_dbg(hub_dev, "TT requires at most %d "
1048 "FS bit times (%d ns)\n",
1049 8, hub->tt.think_time);
1051 break;
1052 case HUB_TTTT_16_BITS:
1053 hub->tt.think_time = 666 * 2;
1054 dev_dbg(hub_dev, "TT requires at most %d "
1055 "FS bit times (%d ns)\n",
1056 16, hub->tt.think_time);
1057 break;
1058 case HUB_TTTT_24_BITS:
1059 hub->tt.think_time = 666 * 3;
1060 dev_dbg(hub_dev, "TT requires at most %d "
1061 "FS bit times (%d ns)\n",
1062 24, hub->tt.think_time);
1063 break;
1064 case HUB_TTTT_32_BITS:
1065 hub->tt.think_time = 666 * 4;
1066 dev_dbg(hub_dev, "TT requires at most %d "
1067 "FS bit times (%d ns)\n",
1068 32, hub->tt.think_time);
1069 break;
1072 /* probe() zeroes hub->indicator[] */
1073 if (wHubCharacteristics & HUB_CHAR_PORTIND) {
1074 hub->has_indicators = 1;
1075 dev_dbg(hub_dev, "Port indicators are supported\n");
1078 dev_dbg(hub_dev, "power on to power good time: %dms\n",
1079 hub->descriptor->bPwrOn2PwrGood * 2);
1081 /* power budgeting mostly matters with bus-powered hubs,
1082 * and battery-powered root hubs (may provide just 8 mA).
1084 ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
1085 if (ret < 2) {
1086 message = "can't get hub status";
1087 goto fail;
1089 le16_to_cpus(&hubstatus);
1090 if (hdev == hdev->bus->root_hub) {
1091 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
1092 hub->mA_per_port = 500;
1093 else {
1094 hub->mA_per_port = hdev->bus_mA;
1095 hub->limited_power = 1;
1097 } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1098 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
1099 hub->descriptor->bHubContrCurrent);
1100 hub->limited_power = 1;
1101 if (hdev->maxchild > 0) {
1102 int remaining = hdev->bus_mA -
1103 hub->descriptor->bHubContrCurrent;
1105 if (remaining < hdev->maxchild * 100)
1106 dev_warn(hub_dev,
1107 "insufficient power available "
1108 "to use all downstream ports\n");
1109 hub->mA_per_port = 100; /* 7.2.1.1 */
1111 } else { /* Self-powered external hub */
1112 /* FIXME: What about battery-powered external hubs that
1113 * provide less current per port? */
1114 hub->mA_per_port = 500;
1116 if (hub->mA_per_port < 500)
1117 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
1118 hub->mA_per_port);
1120 /* Update the HCD's internal representation of this hub before khubd
1121 * starts getting port status changes for devices under the hub.
1123 hcd = bus_to_hcd(hdev->bus);
1124 if (hcd->driver->update_hub_device) {
1125 ret = hcd->driver->update_hub_device(hcd, hdev,
1126 &hub->tt, GFP_KERNEL);
1127 if (ret < 0) {
1128 message = "can't update HCD hub info";
1129 goto fail;
1133 ret = hub_hub_status(hub, &hubstatus, &hubchange);
1134 if (ret < 0) {
1135 message = "can't get hub status";
1136 goto fail;
1139 /* local power status reports aren't always correct */
1140 if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
1141 dev_dbg(hub_dev, "local power source is %s\n",
1142 (hubstatus & HUB_STATUS_LOCAL_POWER)
1143 ? "lost (inactive)" : "good");
1145 if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
1146 dev_dbg(hub_dev, "%sover-current condition exists\n",
1147 (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
1149 /* set up the interrupt endpoint
1150 * We use the EP's maxpacket size instead of (PORTS+1+7)/8
1151 * bytes as USB2.0[11.12.3] says because some hubs are known
1152 * to send more data (and thus cause overflow). For root hubs,
1153 * maxpktsize is defined in hcd.c's fake endpoint descriptors
1154 * to be big enough for at least USB_MAXCHILDREN ports. */
1155 pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
1156 maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
1158 if (maxp > sizeof(*hub->buffer))
1159 maxp = sizeof(*hub->buffer);
1161 hub->urb = usb_alloc_urb(0, GFP_KERNEL);
1162 if (!hub->urb) {
1163 ret = -ENOMEM;
1164 goto fail;
1167 usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1168 hub, endpoint->bInterval);
1170 /* maybe cycle the hub leds */
1171 if (hub->has_indicators && blinkenlights)
1172 hub->indicator [0] = INDICATOR_CYCLE;
1174 hub_activate(hub, HUB_INIT);
1175 return 0;
1177 fail:
1178 dev_err (hub_dev, "config failed, %s (err %d)\n",
1179 message, ret);
1180 /* hub_disconnect() frees urb and descriptor */
1181 return ret;
1184 static void hub_release(struct kref *kref)
1186 struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1188 usb_put_intf(to_usb_interface(hub->intfdev));
1189 kfree(hub);
1192 static unsigned highspeed_hubs;
1194 static void hub_disconnect(struct usb_interface *intf)
1196 struct usb_hub *hub = usb_get_intfdata (intf);
1198 /* Take the hub off the event list and don't let it be added again */
1199 spin_lock_irq(&hub_event_lock);
1200 if (!list_empty(&hub->event_list)) {
1201 list_del_init(&hub->event_list);
1202 usb_autopm_put_interface_no_suspend(intf);
1204 hub->disconnected = 1;
1205 spin_unlock_irq(&hub_event_lock);
1207 /* Disconnect all children and quiesce the hub */
1208 hub->error = 0;
1209 hub_quiesce(hub, HUB_DISCONNECT);
1211 usb_set_intfdata (intf, NULL);
1212 hub->hdev->maxchild = 0;
1214 if (hub->hdev->speed == USB_SPEED_HIGH)
1215 highspeed_hubs--;
1217 usb_free_urb(hub->urb);
1218 kfree(hub->port_owners);
1219 kfree(hub->descriptor);
1220 kfree(hub->status);
1221 kfree(hub->buffer);
1223 kref_put(&hub->kref, hub_release);
1226 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1228 struct usb_host_interface *desc;
1229 struct usb_endpoint_descriptor *endpoint;
1230 struct usb_device *hdev;
1231 struct usb_hub *hub;
1233 desc = intf->cur_altsetting;
1234 hdev = interface_to_usbdev(intf);
1236 /* Hubs have proper suspend/resume support */
1237 usb_enable_autosuspend(hdev);
1239 if (hdev->level == MAX_TOPO_LEVEL) {
1240 dev_err(&intf->dev,
1241 "Unsupported bus topology: hub nested too deep\n");
1242 return -E2BIG;
1245 #ifdef CONFIG_USB_OTG_BLACKLIST_HUB
1246 if (hdev->parent) {
1247 dev_warn(&intf->dev, "ignoring external hub\n");
1248 return -ENODEV;
1250 #endif
1252 /* Some hubs have a subclass of 1, which AFAICT according to the */
1253 /* specs is not defined, but it works */
1254 if ((desc->desc.bInterfaceSubClass != 0) &&
1255 (desc->desc.bInterfaceSubClass != 1)) {
1256 descriptor_error:
1257 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
1258 return -EIO;
1261 /* Multiple endpoints? What kind of mutant ninja-hub is this? */
1262 if (desc->desc.bNumEndpoints != 1)
1263 goto descriptor_error;
1265 endpoint = &desc->endpoint[0].desc;
1267 /* If it's not an interrupt in endpoint, we'd better punt! */
1268 if (!usb_endpoint_is_int_in(endpoint))
1269 goto descriptor_error;
1271 /* We found a hub */
1272 dev_info (&intf->dev, "USB hub found\n");
1274 hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1275 if (!hub) {
1276 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
1277 return -ENOMEM;
1280 kref_init(&hub->kref);
1281 INIT_LIST_HEAD(&hub->event_list);
1282 hub->intfdev = &intf->dev;
1283 hub->hdev = hdev;
1284 INIT_DELAYED_WORK(&hub->leds, led_work);
1285 INIT_DELAYED_WORK(&hub->init_work, NULL);
1286 usb_get_intf(intf);
1288 usb_set_intfdata (intf, hub);
1289 intf->needs_remote_wakeup = 1;
1291 if (hdev->speed == USB_SPEED_HIGH)
1292 highspeed_hubs++;
1294 if (hub_configure(hub, endpoint) >= 0)
1295 return 0;
1297 hub_disconnect (intf);
1298 return -ENODEV;
1301 /* No BKL needed */
1302 static int
1303 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1305 struct usb_device *hdev = interface_to_usbdev (intf);
1307 /* assert ifno == 0 (part of hub spec) */
1308 switch (code) {
1309 case USBDEVFS_HUB_PORTINFO: {
1310 struct usbdevfs_hub_portinfo *info = user_data;
1311 int i;
1313 spin_lock_irq(&device_state_lock);
1314 if (hdev->devnum <= 0)
1315 info->nports = 0;
1316 else {
1317 info->nports = hdev->maxchild;
1318 for (i = 0; i < info->nports; i++) {
1319 if (hdev->children[i] == NULL)
1320 info->port[i] = 0;
1321 else
1322 info->port[i] =
1323 hdev->children[i]->devnum;
1326 spin_unlock_irq(&device_state_lock);
1328 return info->nports + 1;
1331 default:
1332 return -ENOSYS;
1337 * Allow user programs to claim ports on a hub. When a device is attached
1338 * to one of these "claimed" ports, the program will "own" the device.
1340 static int find_port_owner(struct usb_device *hdev, unsigned port1,
1341 void ***ppowner)
1343 if (hdev->state == USB_STATE_NOTATTACHED)
1344 return -ENODEV;
1345 if (port1 == 0 || port1 > hdev->maxchild)
1346 return -EINVAL;
1348 /* This assumes that devices not managed by the hub driver
1349 * will always have maxchild equal to 0.
1351 *ppowner = &(hdev_to_hub(hdev)->port_owners[port1 - 1]);
1352 return 0;
1355 /* In the following three functions, the caller must hold hdev's lock */
1356 int usb_hub_claim_port(struct usb_device *hdev, unsigned port1, void *owner)
1358 int rc;
1359 void **powner;
1361 rc = find_port_owner(hdev, port1, &powner);
1362 if (rc)
1363 return rc;
1364 if (*powner)
1365 return -EBUSY;
1366 *powner = owner;
1367 return rc;
1370 int usb_hub_release_port(struct usb_device *hdev, unsigned port1, void *owner)
1372 int rc;
1373 void **powner;
1375 rc = find_port_owner(hdev, port1, &powner);
1376 if (rc)
1377 return rc;
1378 if (*powner != owner)
1379 return -ENOENT;
1380 *powner = NULL;
1381 return rc;
1384 void usb_hub_release_all_ports(struct usb_device *hdev, void *owner)
1386 int n;
1387 void **powner;
1389 n = find_port_owner(hdev, 1, &powner);
1390 if (n == 0) {
1391 for (; n < hdev->maxchild; (++n, ++powner)) {
1392 if (*powner == owner)
1393 *powner = NULL;
1398 /* The caller must hold udev's lock */
1399 bool usb_device_is_owned(struct usb_device *udev)
1401 struct usb_hub *hub;
1403 if (udev->state == USB_STATE_NOTATTACHED || !udev->parent)
1404 return false;
1405 hub = hdev_to_hub(udev->parent);
1406 return !!hub->port_owners[udev->portnum - 1];
1410 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1412 int i;
1414 for (i = 0; i < udev->maxchild; ++i) {
1415 if (udev->children[i])
1416 recursively_mark_NOTATTACHED(udev->children[i]);
1418 if (udev->state == USB_STATE_SUSPENDED)
1419 udev->active_duration -= jiffies;
1420 udev->state = USB_STATE_NOTATTACHED;
1424 * usb_set_device_state - change a device's current state (usbcore, hcds)
1425 * @udev: pointer to device whose state should be changed
1426 * @new_state: new state value to be stored
1428 * udev->state is _not_ fully protected by the device lock. Although
1429 * most transitions are made only while holding the lock, the state can
1430 * can change to USB_STATE_NOTATTACHED at almost any time. This
1431 * is so that devices can be marked as disconnected as soon as possible,
1432 * without having to wait for any semaphores to be released. As a result,
1433 * all changes to any device's state must be protected by the
1434 * device_state_lock spinlock.
1436 * Once a device has been added to the device tree, all changes to its state
1437 * should be made using this routine. The state should _not_ be set directly.
1439 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1440 * Otherwise udev->state is set to new_state, and if new_state is
1441 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1442 * to USB_STATE_NOTATTACHED.
1444 void usb_set_device_state(struct usb_device *udev,
1445 enum usb_device_state new_state)
1447 unsigned long flags;
1449 spin_lock_irqsave(&device_state_lock, flags);
1450 if (udev->state == USB_STATE_NOTATTACHED)
1451 ; /* do nothing */
1452 else if (new_state != USB_STATE_NOTATTACHED) {
1454 /* root hub wakeup capabilities are managed out-of-band
1455 * and may involve silicon errata ... ignore them here.
1457 if (udev->parent) {
1458 if (udev->state == USB_STATE_SUSPENDED
1459 || new_state == USB_STATE_SUSPENDED)
1460 ; /* No change to wakeup settings */
1461 else if (new_state == USB_STATE_CONFIGURED)
1462 device_set_wakeup_capable(&udev->dev,
1463 (udev->actconfig->desc.bmAttributes
1464 & USB_CONFIG_ATT_WAKEUP));
1465 else
1466 device_set_wakeup_capable(&udev->dev, 0);
1468 if (udev->state == USB_STATE_SUSPENDED &&
1469 new_state != USB_STATE_SUSPENDED)
1470 udev->active_duration -= jiffies;
1471 else if (new_state == USB_STATE_SUSPENDED &&
1472 udev->state != USB_STATE_SUSPENDED)
1473 udev->active_duration += jiffies;
1474 udev->state = new_state;
1475 } else
1476 recursively_mark_NOTATTACHED(udev);
1477 spin_unlock_irqrestore(&device_state_lock, flags);
1479 EXPORT_SYMBOL_GPL(usb_set_device_state);
1482 * WUSB devices are simple: they have no hubs behind, so the mapping
1483 * device <-> virtual port number becomes 1:1. Why? to simplify the
1484 * life of the device connection logic in
1485 * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
1486 * handshake we need to assign a temporary address in the unauthorized
1487 * space. For simplicity we use the first virtual port number found to
1488 * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
1489 * and that becomes it's address [X < 128] or its unauthorized address
1490 * [X | 0x80].
1492 * We add 1 as an offset to the one-based USB-stack port number
1493 * (zero-based wusb virtual port index) for two reasons: (a) dev addr
1494 * 0 is reserved by USB for default address; (b) Linux's USB stack
1495 * uses always #1 for the root hub of the controller. So USB stack's
1496 * port #1, which is wusb virtual-port #0 has address #2.
1498 * Devices connected under xHCI are not as simple. The host controller
1499 * supports virtualization, so the hardware assigns device addresses and
1500 * the HCD must setup data structures before issuing a set address
1501 * command to the hardware.
1503 static void choose_address(struct usb_device *udev)
1505 int devnum;
1506 struct usb_bus *bus = udev->bus;
1508 /* If khubd ever becomes multithreaded, this will need a lock */
1509 if (udev->wusb) {
1510 devnum = udev->portnum + 1;
1511 BUG_ON(test_bit(devnum, bus->devmap.devicemap));
1512 } else {
1513 /* Try to allocate the next devnum beginning at
1514 * bus->devnum_next. */
1515 devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1516 bus->devnum_next);
1517 if (devnum >= 128)
1518 devnum = find_next_zero_bit(bus->devmap.devicemap,
1519 128, 1);
1520 bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1522 if (devnum < 128) {
1523 set_bit(devnum, bus->devmap.devicemap);
1524 udev->devnum = devnum;
1528 static void release_address(struct usb_device *udev)
1530 if (udev->devnum > 0) {
1531 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1532 udev->devnum = -1;
1536 static void update_address(struct usb_device *udev, int devnum)
1538 /* The address for a WUSB device is managed by wusbcore. */
1539 if (!udev->wusb)
1540 udev->devnum = devnum;
1543 static void hub_free_dev(struct usb_device *udev)
1545 struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1547 /* Root hubs aren't real devices, so don't free HCD resources */
1548 if (hcd->driver->free_dev && udev->parent)
1549 hcd->driver->free_dev(hcd, udev);
1553 * usb_disconnect - disconnect a device (usbcore-internal)
1554 * @pdev: pointer to device being disconnected
1555 * Context: !in_interrupt ()
1557 * Something got disconnected. Get rid of it and all of its children.
1559 * If *pdev is a normal device then the parent hub must already be locked.
1560 * If *pdev is a root hub then this routine will acquire the
1561 * usb_bus_list_lock on behalf of the caller.
1563 * Only hub drivers (including virtual root hub drivers for host
1564 * controllers) should ever call this.
1566 * This call is synchronous, and may not be used in an interrupt context.
1568 void usb_disconnect(struct usb_device **pdev)
1570 struct usb_device *udev = *pdev;
1571 int i;
1573 if (!udev) {
1574 pr_debug ("%s nodev\n", __func__);
1575 return;
1578 /* mark the device as inactive, so any further urb submissions for
1579 * this device (and any of its children) will fail immediately.
1580 * this quiesces everyting except pending urbs.
1582 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1583 dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1585 usb_lock_device(udev);
1587 /* Free up all the children before we remove this device */
1588 for (i = 0; i < USB_MAXCHILDREN; i++) {
1589 if (udev->children[i])
1590 usb_disconnect(&udev->children[i]);
1593 /* deallocate hcd/hardware state ... nuking all pending urbs and
1594 * cleaning up all state associated with the current configuration
1595 * so that the hardware is now fully quiesced.
1597 dev_dbg (&udev->dev, "unregistering device\n");
1598 usb_disable_device(udev, 0);
1599 usb_hcd_synchronize_unlinks(udev);
1601 usb_remove_ep_devs(&udev->ep0);
1602 usb_unlock_device(udev);
1604 /* Unregister the device. The device driver is responsible
1605 * for de-configuring the device and invoking the remove-device
1606 * notifier chain (used by usbfs and possibly others).
1608 device_del(&udev->dev);
1610 /* Free the device number and delete the parent's children[]
1611 * (or root_hub) pointer.
1613 release_address(udev);
1615 /* Avoid races with recursively_mark_NOTATTACHED() */
1616 spin_lock_irq(&device_state_lock);
1617 *pdev = NULL;
1618 spin_unlock_irq(&device_state_lock);
1620 hub_free_dev(udev);
1622 put_device(&udev->dev);
1625 #ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
1626 static void show_string(struct usb_device *udev, char *id, char *string)
1628 if (!string)
1629 return;
1630 dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1633 static void announce_device(struct usb_device *udev)
1635 dev_info(&udev->dev, "New USB device found, idVendor=%04x, idProduct=%04x\n",
1636 le16_to_cpu(udev->descriptor.idVendor),
1637 le16_to_cpu(udev->descriptor.idProduct));
1638 dev_info(&udev->dev,
1639 "New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
1640 udev->descriptor.iManufacturer,
1641 udev->descriptor.iProduct,
1642 udev->descriptor.iSerialNumber);
1643 show_string(udev, "Product", udev->product);
1644 show_string(udev, "Manufacturer", udev->manufacturer);
1645 show_string(udev, "SerialNumber", udev->serial);
1647 #else
1648 static inline void announce_device(struct usb_device *udev) { }
1649 #endif
1651 #ifdef CONFIG_USB_OTG
1652 #include "otg_whitelist.h"
1653 #endif
1656 * usb_enumerate_device_otg - FIXME (usbcore-internal)
1657 * @udev: newly addressed device (in ADDRESS state)
1659 * Finish enumeration for On-The-Go devices
1661 static int usb_enumerate_device_otg(struct usb_device *udev)
1663 int err = 0;
1665 #ifdef CONFIG_USB_OTG
1667 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1668 * to wake us after we've powered off VBUS; and HNP, switching roles
1669 * "host" to "peripheral". The OTG descriptor helps figure this out.
1671 if (!udev->bus->is_b_host
1672 && udev->config
1673 && udev->parent == udev->bus->root_hub) {
1674 struct usb_otg_descriptor *desc = NULL;
1675 struct usb_bus *bus = udev->bus;
1677 /* descriptor may appear anywhere in config */
1678 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1679 le16_to_cpu(udev->config[0].desc.wTotalLength),
1680 USB_DT_OTG, (void **) &desc) == 0) {
1681 if (desc->bmAttributes & USB_OTG_HNP) {
1682 unsigned port1 = udev->portnum;
1684 dev_info(&udev->dev,
1685 "Dual-Role OTG device on %sHNP port\n",
1686 (port1 == bus->otg_port)
1687 ? "" : "non-");
1689 /* enable HNP before suspend, it's simpler */
1690 if (port1 == bus->otg_port)
1691 bus->b_hnp_enable = 1;
1692 err = usb_control_msg(udev,
1693 usb_sndctrlpipe(udev, 0),
1694 USB_REQ_SET_FEATURE, 0,
1695 bus->b_hnp_enable
1696 ? USB_DEVICE_B_HNP_ENABLE
1697 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1698 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1699 if (err < 0) {
1700 /* OTG MESSAGE: report errors here,
1701 * customize to match your product.
1703 dev_info(&udev->dev,
1704 "can't set HNP mode: %d\n",
1705 err);
1706 bus->b_hnp_enable = 0;
1712 if (!is_targeted(udev)) {
1714 /* Maybe it can talk to us, though we can't talk to it.
1715 * (Includes HNP test device.)
1717 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1718 err = usb_port_suspend(udev, PMSG_SUSPEND);
1719 if (err < 0)
1720 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1722 err = -ENOTSUPP;
1723 goto fail;
1725 fail:
1726 #endif
1727 return err;
1732 * usb_enumerate_device - Read device configs/intfs/otg (usbcore-internal)
1733 * @udev: newly addressed device (in ADDRESS state)
1735 * This is only called by usb_new_device() and usb_authorize_device()
1736 * and FIXME -- all comments that apply to them apply here wrt to
1737 * environment.
1739 * If the device is WUSB and not authorized, we don't attempt to read
1740 * the string descriptors, as they will be errored out by the device
1741 * until it has been authorized.
1743 static int usb_enumerate_device(struct usb_device *udev)
1745 int err;
1747 if (udev->config == NULL) {
1748 err = usb_get_configuration(udev);
1749 if (err < 0) {
1750 dev_err(&udev->dev, "can't read configurations, error %d\n",
1751 err);
1752 goto fail;
1755 if (udev->wusb == 1 && udev->authorized == 0) {
1756 udev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1757 udev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1758 udev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1760 else {
1761 /* read the standard strings and cache them if present */
1762 udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1763 udev->manufacturer = usb_cache_string(udev,
1764 udev->descriptor.iManufacturer);
1765 udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1767 err = usb_enumerate_device_otg(udev);
1768 fail:
1769 return err;
1774 * usb_new_device - perform initial device setup (usbcore-internal)
1775 * @udev: newly addressed device (in ADDRESS state)
1777 * This is called with devices which have been detected but not fully
1778 * enumerated. The device descriptor is available, but not descriptors
1779 * for any device configuration. The caller must have locked either
1780 * the parent hub (if udev is a normal device) or else the
1781 * usb_bus_list_lock (if udev is a root hub). The parent's pointer to
1782 * udev has already been installed, but udev is not yet visible through
1783 * sysfs or other filesystem code.
1785 * It will return if the device is configured properly or not. Zero if
1786 * the interface was registered with the driver core; else a negative
1787 * errno value.
1789 * This call is synchronous, and may not be used in an interrupt context.
1791 * Only the hub driver or root-hub registrar should ever call this.
1793 int usb_new_device(struct usb_device *udev)
1795 int err;
1797 if (udev->parent) {
1798 /* Initialize non-root-hub device wakeup to disabled;
1799 * device (un)configuration controls wakeup capable
1800 * sysfs power/wakeup controls wakeup enabled/disabled
1802 device_init_wakeup(&udev->dev, 0);
1805 /* Tell the runtime-PM framework the device is active */
1806 pm_runtime_set_active(&udev->dev);
1807 pm_runtime_enable(&udev->dev);
1809 err = usb_enumerate_device(udev); /* Read descriptors */
1810 if (err < 0)
1811 goto fail;
1812 dev_dbg(&udev->dev, "udev %d, busnum %d, minor = %d\n",
1813 udev->devnum, udev->bus->busnum,
1814 (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
1815 /* export the usbdev device-node for libusb */
1816 udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
1817 (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
1819 /* Tell the world! */
1820 announce_device(udev);
1822 device_enable_async_suspend(&udev->dev);
1823 /* Register the device. The device driver is responsible
1824 * for configuring the device and invoking the add-device
1825 * notifier chain (used by usbfs and possibly others).
1827 err = device_add(&udev->dev);
1828 if (err) {
1829 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1830 goto fail;
1833 (void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev);
1834 return err;
1836 fail:
1837 usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1838 pm_runtime_disable(&udev->dev);
1839 pm_runtime_set_suspended(&udev->dev);
1840 return err;
1845 * usb_deauthorize_device - deauthorize a device (usbcore-internal)
1846 * @usb_dev: USB device
1848 * Move the USB device to a very basic state where interfaces are disabled
1849 * and the device is in fact unconfigured and unusable.
1851 * We share a lock (that we have) with device_del(), so we need to
1852 * defer its call.
1854 int usb_deauthorize_device(struct usb_device *usb_dev)
1856 usb_lock_device(usb_dev);
1857 if (usb_dev->authorized == 0)
1858 goto out_unauthorized;
1860 usb_dev->authorized = 0;
1861 usb_set_configuration(usb_dev, -1);
1863 kfree(usb_dev->product);
1864 usb_dev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1865 kfree(usb_dev->manufacturer);
1866 usb_dev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1867 kfree(usb_dev->serial);
1868 usb_dev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1870 usb_destroy_configuration(usb_dev);
1871 usb_dev->descriptor.bNumConfigurations = 0;
1873 out_unauthorized:
1874 usb_unlock_device(usb_dev);
1875 return 0;
1879 int usb_authorize_device(struct usb_device *usb_dev)
1881 int result = 0, c;
1883 usb_lock_device(usb_dev);
1884 if (usb_dev->authorized == 1)
1885 goto out_authorized;
1887 result = usb_autoresume_device(usb_dev);
1888 if (result < 0) {
1889 dev_err(&usb_dev->dev,
1890 "can't autoresume for authorization: %d\n", result);
1891 goto error_autoresume;
1893 result = usb_get_device_descriptor(usb_dev, sizeof(usb_dev->descriptor));
1894 if (result < 0) {
1895 dev_err(&usb_dev->dev, "can't re-read device descriptor for "
1896 "authorization: %d\n", result);
1897 goto error_device_descriptor;
1900 kfree(usb_dev->product);
1901 usb_dev->product = NULL;
1902 kfree(usb_dev->manufacturer);
1903 usb_dev->manufacturer = NULL;
1904 kfree(usb_dev->serial);
1905 usb_dev->serial = NULL;
1907 usb_dev->authorized = 1;
1908 result = usb_enumerate_device(usb_dev);
1909 if (result < 0)
1910 goto error_enumerate;
1911 /* Choose and set the configuration. This registers the interfaces
1912 * with the driver core and lets interface drivers bind to them.
1914 c = usb_choose_configuration(usb_dev);
1915 if (c >= 0) {
1916 result = usb_set_configuration(usb_dev, c);
1917 if (result) {
1918 dev_err(&usb_dev->dev,
1919 "can't set config #%d, error %d\n", c, result);
1920 /* This need not be fatal. The user can try to
1921 * set other configurations. */
1924 dev_info(&usb_dev->dev, "authorized to connect\n");
1926 error_enumerate:
1927 error_device_descriptor:
1928 usb_autosuspend_device(usb_dev);
1929 error_autoresume:
1930 out_authorized:
1931 usb_unlock_device(usb_dev); // complements locktree
1932 return result;
1936 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
1937 static unsigned hub_is_wusb(struct usb_hub *hub)
1939 struct usb_hcd *hcd;
1940 if (hub->hdev->parent != NULL) /* not a root hub? */
1941 return 0;
1942 hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
1943 return hcd->wireless;
1947 #define PORT_RESET_TRIES 5
1948 #define SET_ADDRESS_TRIES 2
1949 #define GET_DESCRIPTOR_TRIES 2
1950 #define SET_CONFIG_TRIES (2 * (use_both_schemes + 1))
1951 #define USE_NEW_SCHEME(i) ((i) / 2 == old_scheme_first)
1953 #define HUB_ROOT_RESET_TIME 50 /* times are in msec */
1954 #define HUB_SHORT_RESET_TIME 10
1955 #define HUB_LONG_RESET_TIME 200
1956 #define HUB_RESET_TIMEOUT 500
1958 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1959 struct usb_device *udev, unsigned int delay)
1961 int delay_time, ret;
1962 u16 portstatus;
1963 u16 portchange;
1965 for (delay_time = 0;
1966 delay_time < HUB_RESET_TIMEOUT;
1967 delay_time += delay) {
1968 /* wait to give the device a chance to reset */
1969 msleep(delay);
1971 /* read and decode port status */
1972 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1973 if (ret < 0)
1974 return ret;
1976 /* Device went away? */
1977 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1978 return -ENOTCONN;
1980 /* bomb out completely if the connection bounced */
1981 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1982 return -ENOTCONN;
1984 /* if we`ve finished resetting, then break out of the loop */
1985 if (!(portstatus & USB_PORT_STAT_RESET) &&
1986 (portstatus & USB_PORT_STAT_ENABLE)) {
1987 if (hub_is_wusb(hub))
1988 udev->speed = USB_SPEED_WIRELESS;
1989 else if (portstatus & USB_PORT_STAT_SUPER_SPEED)
1990 udev->speed = USB_SPEED_SUPER;
1991 else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1992 udev->speed = USB_SPEED_HIGH;
1993 else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1994 udev->speed = USB_SPEED_LOW;
1995 else
1996 udev->speed = USB_SPEED_FULL;
1997 return 0;
2000 /* switch to the long delay after two short delay failures */
2001 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
2002 delay = HUB_LONG_RESET_TIME;
2004 dev_dbg (hub->intfdev,
2005 "port %d not reset yet, waiting %dms\n",
2006 port1, delay);
2009 return -EBUSY;
2012 static int hub_port_reset(struct usb_hub *hub, int port1,
2013 struct usb_device *udev, unsigned int delay)
2015 int i, status;
2016 struct usb_hcd *hcd;
2018 hcd = bus_to_hcd(udev->bus);
2019 /* Block EHCI CF initialization during the port reset.
2020 * Some companion controllers don't like it when they mix.
2022 down_read(&ehci_cf_port_reset_rwsem);
2024 /* Reset the port */
2025 for (i = 0; i < PORT_RESET_TRIES; i++) {
2026 status = set_port_feature(hub->hdev,
2027 port1, USB_PORT_FEAT_RESET);
2028 if (status)
2029 dev_err(hub->intfdev,
2030 "cannot reset port %d (err = %d)\n",
2031 port1, status);
2032 else {
2033 status = hub_port_wait_reset(hub, port1, udev, delay);
2034 if (status && status != -ENOTCONN)
2035 dev_dbg(hub->intfdev,
2036 "port_wait_reset: err = %d\n",
2037 status);
2040 /* return on disconnect or reset */
2041 switch (status) {
2042 case 0:
2043 /* TRSTRCY = 10 ms; plus some extra */
2044 msleep(10 + 40);
2045 update_address(udev, 0);
2046 if (hcd->driver->reset_device) {
2047 status = hcd->driver->reset_device(hcd, udev);
2048 if (status < 0) {
2049 dev_err(&udev->dev, "Cannot reset "
2050 "HCD device state\n");
2051 break;
2054 /* FALL THROUGH */
2055 case -ENOTCONN:
2056 case -ENODEV:
2057 clear_port_feature(hub->hdev,
2058 port1, USB_PORT_FEAT_C_RESET);
2059 /* FIXME need disconnect() for NOTATTACHED device */
2060 usb_set_device_state(udev, status
2061 ? USB_STATE_NOTATTACHED
2062 : USB_STATE_DEFAULT);
2063 goto done;
2066 dev_dbg (hub->intfdev,
2067 "port %d not enabled, trying reset again...\n",
2068 port1);
2069 delay = HUB_LONG_RESET_TIME;
2072 dev_err (hub->intfdev,
2073 "Cannot enable port %i. Maybe the USB cable is bad?\n",
2074 port1);
2076 done:
2077 up_read(&ehci_cf_port_reset_rwsem);
2078 return status;
2081 #ifdef CONFIG_PM
2083 #define MASK_BITS (USB_PORT_STAT_POWER | USB_PORT_STAT_CONNECTION | \
2084 USB_PORT_STAT_SUSPEND)
2085 #define WANT_BITS (USB_PORT_STAT_POWER | USB_PORT_STAT_CONNECTION)
2087 /* Determine whether the device on a port is ready for a normal resume,
2088 * is ready for a reset-resume, or should be disconnected.
2090 static int check_port_resume_type(struct usb_device *udev,
2091 struct usb_hub *hub, int port1,
2092 int status, unsigned portchange, unsigned portstatus)
2094 /* Is the device still present? */
2095 if (status || (portstatus & MASK_BITS) != WANT_BITS) {
2096 if (status >= 0)
2097 status = -ENODEV;
2100 /* Can't do a normal resume if the port isn't enabled,
2101 * so try a reset-resume instead.
2103 else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
2104 if (udev->persist_enabled)
2105 udev->reset_resume = 1;
2106 else
2107 status = -ENODEV;
2110 if (status) {
2111 dev_dbg(hub->intfdev,
2112 "port %d status %04x.%04x after resume, %d\n",
2113 port1, portchange, portstatus, status);
2114 } else if (udev->reset_resume) {
2116 /* Late port handoff can set status-change bits */
2117 if (portchange & USB_PORT_STAT_C_CONNECTION)
2118 clear_port_feature(hub->hdev, port1,
2119 USB_PORT_FEAT_C_CONNECTION);
2120 if (portchange & USB_PORT_STAT_C_ENABLE)
2121 clear_port_feature(hub->hdev, port1,
2122 USB_PORT_FEAT_C_ENABLE);
2125 return status;
2128 #ifdef CONFIG_USB_SUSPEND
2131 * usb_port_suspend - suspend a usb device's upstream port
2132 * @udev: device that's no longer in active use, not a root hub
2133 * Context: must be able to sleep; device not locked; pm locks held
2135 * Suspends a USB device that isn't in active use, conserving power.
2136 * Devices may wake out of a suspend, if anything important happens,
2137 * using the remote wakeup mechanism. They may also be taken out of
2138 * suspend by the host, using usb_port_resume(). It's also routine
2139 * to disconnect devices while they are suspended.
2141 * This only affects the USB hardware for a device; its interfaces
2142 * (and, for hubs, child devices) must already have been suspended.
2144 * Selective port suspend reduces power; most suspended devices draw
2145 * less than 500 uA. It's also used in OTG, along with remote wakeup.
2146 * All devices below the suspended port are also suspended.
2148 * Devices leave suspend state when the host wakes them up. Some devices
2149 * also support "remote wakeup", where the device can activate the USB
2150 * tree above them to deliver data, such as a keypress or packet. In
2151 * some cases, this wakes the USB host.
2153 * Suspending OTG devices may trigger HNP, if that's been enabled
2154 * between a pair of dual-role devices. That will change roles, such
2155 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
2157 * Devices on USB hub ports have only one "suspend" state, corresponding
2158 * to ACPI D2, "may cause the device to lose some context".
2159 * State transitions include:
2161 * - suspend, resume ... when the VBUS power link stays live
2162 * - suspend, disconnect ... VBUS lost
2164 * Once VBUS drop breaks the circuit, the port it's using has to go through
2165 * normal re-enumeration procedures, starting with enabling VBUS power.
2166 * Other than re-initializing the hub (plug/unplug, except for root hubs),
2167 * Linux (2.6) currently has NO mechanisms to initiate that: no khubd
2168 * timer, no SRP, no requests through sysfs.
2170 * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
2171 * the root hub for their bus goes into global suspend ... so we don't
2172 * (falsely) update the device power state to say it suspended.
2174 * Returns 0 on success, else negative errno.
2176 int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
2178 struct usb_hub *hub = hdev_to_hub(udev->parent);
2179 int port1 = udev->portnum;
2180 int status;
2182 // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
2184 /* enable remote wakeup when appropriate; this lets the device
2185 * wake up the upstream hub (including maybe the root hub).
2187 * NOTE: OTG devices may issue remote wakeup (or SRP) even when
2188 * we don't explicitly enable it here.
2190 if (udev->do_remote_wakeup) {
2191 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2192 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
2193 USB_DEVICE_REMOTE_WAKEUP, 0,
2194 NULL, 0,
2195 USB_CTRL_SET_TIMEOUT);
2196 if (status) {
2197 dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
2198 status);
2199 /* bail if autosuspend is requested */
2200 if (msg.event & PM_EVENT_AUTO)
2201 return status;
2205 /* see 7.1.7.6 */
2206 status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
2207 if (status) {
2208 dev_dbg(hub->intfdev, "can't suspend port %d, status %d\n",
2209 port1, status);
2210 /* paranoia: "should not happen" */
2211 if (udev->do_remote_wakeup)
2212 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2213 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
2214 USB_DEVICE_REMOTE_WAKEUP, 0,
2215 NULL, 0,
2216 USB_CTRL_SET_TIMEOUT);
2217 } else {
2218 /* device has up to 10 msec to fully suspend */
2219 dev_dbg(&udev->dev, "usb %ssuspend\n",
2220 (msg.event & PM_EVENT_AUTO ? "auto-" : ""));
2221 usb_set_device_state(udev, USB_STATE_SUSPENDED);
2222 msleep(10);
2224 return status;
2228 * If the USB "suspend" state is in use (rather than "global suspend"),
2229 * many devices will be individually taken out of suspend state using
2230 * special "resume" signaling. This routine kicks in shortly after
2231 * hardware resume signaling is finished, either because of selective
2232 * resume (by host) or remote wakeup (by device) ... now see what changed
2233 * in the tree that's rooted at this device.
2235 * If @udev->reset_resume is set then the device is reset before the
2236 * status check is done.
2238 static int finish_port_resume(struct usb_device *udev)
2240 int status = 0;
2241 u16 devstatus;
2243 /* caller owns the udev device lock */
2244 dev_dbg(&udev->dev, "%s\n",
2245 udev->reset_resume ? "finish reset-resume" : "finish resume");
2247 /* usb ch9 identifies four variants of SUSPENDED, based on what
2248 * state the device resumes to. Linux currently won't see the
2249 * first two on the host side; they'd be inside hub_port_init()
2250 * during many timeouts, but khubd can't suspend until later.
2252 usb_set_device_state(udev, udev->actconfig
2253 ? USB_STATE_CONFIGURED
2254 : USB_STATE_ADDRESS);
2256 /* 10.5.4.5 says not to reset a suspended port if the attached
2257 * device is enabled for remote wakeup. Hence the reset
2258 * operation is carried out here, after the port has been
2259 * resumed.
2261 if (udev->reset_resume)
2262 retry_reset_resume:
2263 status = usb_reset_and_verify_device(udev);
2265 /* 10.5.4.5 says be sure devices in the tree are still there.
2266 * For now let's assume the device didn't go crazy on resume,
2267 * and device drivers will know about any resume quirks.
2269 if (status == 0) {
2270 devstatus = 0;
2271 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
2272 if (status >= 0)
2273 status = (status > 0 ? 0 : -ENODEV);
2275 /* If a normal resume failed, try doing a reset-resume */
2276 if (status && !udev->reset_resume && udev->persist_enabled) {
2277 dev_dbg(&udev->dev, "retry with reset-resume\n");
2278 udev->reset_resume = 1;
2279 goto retry_reset_resume;
2283 if (status) {
2284 dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
2285 status);
2286 } else if (udev->actconfig) {
2287 le16_to_cpus(&devstatus);
2288 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
2289 status = usb_control_msg(udev,
2290 usb_sndctrlpipe(udev, 0),
2291 USB_REQ_CLEAR_FEATURE,
2292 USB_RECIP_DEVICE,
2293 USB_DEVICE_REMOTE_WAKEUP, 0,
2294 NULL, 0,
2295 USB_CTRL_SET_TIMEOUT);
2296 if (status)
2297 dev_dbg(&udev->dev,
2298 "disable remote wakeup, status %d\n",
2299 status);
2301 status = 0;
2303 return status;
2307 * usb_port_resume - re-activate a suspended usb device's upstream port
2308 * @udev: device to re-activate, not a root hub
2309 * Context: must be able to sleep; device not locked; pm locks held
2311 * This will re-activate the suspended device, increasing power usage
2312 * while letting drivers communicate again with its endpoints.
2313 * USB resume explicitly guarantees that the power session between
2314 * the host and the device is the same as it was when the device
2315 * suspended.
2317 * If @udev->reset_resume is set then this routine won't check that the
2318 * port is still enabled. Furthermore, finish_port_resume() above will
2319 * reset @udev. The end result is that a broken power session can be
2320 * recovered and @udev will appear to persist across a loss of VBUS power.
2322 * For example, if a host controller doesn't maintain VBUS suspend current
2323 * during a system sleep or is reset when the system wakes up, all the USB
2324 * power sessions below it will be broken. This is especially troublesome
2325 * for mass-storage devices containing mounted filesystems, since the
2326 * device will appear to have disconnected and all the memory mappings
2327 * to it will be lost. Using the USB_PERSIST facility, the device can be
2328 * made to appear as if it had not disconnected.
2330 * This facility can be dangerous. Although usb_reset_and_verify_device() makes
2331 * every effort to insure that the same device is present after the
2332 * reset as before, it cannot provide a 100% guarantee. Furthermore it's
2333 * quite possible for a device to remain unaltered but its media to be
2334 * changed. If the user replaces a flash memory card while the system is
2335 * asleep, he will have only himself to blame when the filesystem on the
2336 * new card is corrupted and the system crashes.
2338 * Returns 0 on success, else negative errno.
2340 int usb_port_resume(struct usb_device *udev, pm_message_t msg)
2342 struct usb_hub *hub = hdev_to_hub(udev->parent);
2343 int port1 = udev->portnum;
2344 int status;
2345 u16 portchange, portstatus;
2347 /* Skip the initial Clear-Suspend step for a remote wakeup */
2348 status = hub_port_status(hub, port1, &portstatus, &portchange);
2349 if (status == 0 && !(portstatus & USB_PORT_STAT_SUSPEND))
2350 goto SuspendCleared;
2352 // dev_dbg(hub->intfdev, "resume port %d\n", port1);
2354 set_bit(port1, hub->busy_bits);
2356 /* see 7.1.7.7; affects power usage, but not budgeting */
2357 status = clear_port_feature(hub->hdev,
2358 port1, USB_PORT_FEAT_SUSPEND);
2359 if (status) {
2360 dev_dbg(hub->intfdev, "can't resume port %d, status %d\n",
2361 port1, status);
2362 } else {
2363 /* drive resume for at least 20 msec */
2364 dev_dbg(&udev->dev, "usb %sresume\n",
2365 (msg.event & PM_EVENT_AUTO ? "auto-" : ""));
2366 msleep(25);
2368 /* Virtual root hubs can trigger on GET_PORT_STATUS to
2369 * stop resume signaling. Then finish the resume
2370 * sequence.
2372 status = hub_port_status(hub, port1, &portstatus, &portchange);
2374 /* TRSMRCY = 10 msec */
2375 msleep(10);
2378 SuspendCleared:
2379 if (status == 0) {
2380 if (portchange & USB_PORT_STAT_C_SUSPEND)
2381 clear_port_feature(hub->hdev, port1,
2382 USB_PORT_FEAT_C_SUSPEND);
2385 clear_bit(port1, hub->busy_bits);
2387 status = check_port_resume_type(udev,
2388 hub, port1, status, portchange, portstatus);
2389 if (status == 0)
2390 status = finish_port_resume(udev);
2391 if (status < 0) {
2392 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2393 hub_port_logical_disconnect(hub, port1);
2395 return status;
2398 /* caller has locked udev */
2399 int usb_remote_wakeup(struct usb_device *udev)
2401 int status = 0;
2403 if (udev->state == USB_STATE_SUSPENDED) {
2404 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
2405 status = usb_autoresume_device(udev);
2406 if (status == 0) {
2407 /* Let the drivers do their thing, then... */
2408 usb_autosuspend_device(udev);
2411 return status;
2414 #else /* CONFIG_USB_SUSPEND */
2416 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
2418 int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
2420 return 0;
2423 /* However we may need to do a reset-resume */
2425 int usb_port_resume(struct usb_device *udev, pm_message_t msg)
2427 struct usb_hub *hub = hdev_to_hub(udev->parent);
2428 int port1 = udev->portnum;
2429 int status;
2430 u16 portchange, portstatus;
2432 status = hub_port_status(hub, port1, &portstatus, &portchange);
2433 status = check_port_resume_type(udev,
2434 hub, port1, status, portchange, portstatus);
2436 if (status) {
2437 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2438 hub_port_logical_disconnect(hub, port1);
2439 } else if (udev->reset_resume) {
2440 dev_dbg(&udev->dev, "reset-resume\n");
2441 status = usb_reset_and_verify_device(udev);
2443 return status;
2446 #endif
2448 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
2450 struct usb_hub *hub = usb_get_intfdata (intf);
2451 struct usb_device *hdev = hub->hdev;
2452 unsigned port1;
2454 /* fail if children aren't already suspended */
2455 for (port1 = 1; port1 <= hdev->maxchild; port1++) {
2456 struct usb_device *udev;
2458 udev = hdev->children [port1-1];
2459 if (udev && udev->can_submit) {
2460 if (!(msg.event & PM_EVENT_AUTO))
2461 dev_dbg(&intf->dev, "port %d nyet suspended\n",
2462 port1);
2463 return -EBUSY;
2467 dev_dbg(&intf->dev, "%s\n", __func__);
2469 /* stop khubd and related activity */
2470 hub_quiesce(hub, HUB_SUSPEND);
2471 return 0;
2474 static int hub_resume(struct usb_interface *intf)
2476 struct usb_hub *hub = usb_get_intfdata(intf);
2478 dev_dbg(&intf->dev, "%s\n", __func__);
2479 hub_activate(hub, HUB_RESUME);
2480 return 0;
2483 static int hub_reset_resume(struct usb_interface *intf)
2485 struct usb_hub *hub = usb_get_intfdata(intf);
2487 dev_dbg(&intf->dev, "%s\n", __func__);
2488 hub_activate(hub, HUB_RESET_RESUME);
2489 return 0;
2493 * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
2494 * @rhdev: struct usb_device for the root hub
2496 * The USB host controller driver calls this function when its root hub
2497 * is resumed and Vbus power has been interrupted or the controller
2498 * has been reset. The routine marks @rhdev as having lost power.
2499 * When the hub driver is resumed it will take notice and carry out
2500 * power-session recovery for all the "USB-PERSIST"-enabled child devices;
2501 * the others will be disconnected.
2503 void usb_root_hub_lost_power(struct usb_device *rhdev)
2505 dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
2506 rhdev->reset_resume = 1;
2508 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
2510 #else /* CONFIG_PM */
2512 #define hub_suspend NULL
2513 #define hub_resume NULL
2514 #define hub_reset_resume NULL
2515 #endif
2518 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2520 * Between connect detection and reset signaling there must be a delay
2521 * of 100ms at least for debounce and power-settling. The corresponding
2522 * timer shall restart whenever the downstream port detects a disconnect.
2524 * Apparently there are some bluetooth and irda-dongles and a number of
2525 * low-speed devices for which this debounce period may last over a second.
2526 * Not covered by the spec - but easy to deal with.
2528 * This implementation uses a 1500ms total debounce timeout; if the
2529 * connection isn't stable by then it returns -ETIMEDOUT. It checks
2530 * every 25ms for transient disconnects. When the port status has been
2531 * unchanged for 100ms it returns the port status.
2533 static int hub_port_debounce(struct usb_hub *hub, int port1)
2535 int ret;
2536 int total_time, stable_time = 0;
2537 u16 portchange, portstatus;
2538 unsigned connection = 0xffff;
2540 for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2541 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2542 if (ret < 0)
2543 return ret;
2545 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2546 (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2547 stable_time += HUB_DEBOUNCE_STEP;
2548 if (stable_time >= HUB_DEBOUNCE_STABLE)
2549 break;
2550 } else {
2551 stable_time = 0;
2552 connection = portstatus & USB_PORT_STAT_CONNECTION;
2555 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2556 clear_port_feature(hub->hdev, port1,
2557 USB_PORT_FEAT_C_CONNECTION);
2560 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2561 break;
2562 msleep(HUB_DEBOUNCE_STEP);
2565 dev_dbg (hub->intfdev,
2566 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2567 port1, total_time, stable_time, portstatus);
2569 if (stable_time < HUB_DEBOUNCE_STABLE)
2570 return -ETIMEDOUT;
2571 return portstatus;
2574 void usb_ep0_reinit(struct usb_device *udev)
2576 usb_disable_endpoint(udev, 0 + USB_DIR_IN, true);
2577 usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true);
2578 usb_enable_endpoint(udev, &udev->ep0, true);
2580 EXPORT_SYMBOL_GPL(usb_ep0_reinit);
2582 #define usb_sndaddr0pipe() (PIPE_CONTROL << 30)
2583 #define usb_rcvaddr0pipe() ((PIPE_CONTROL << 30) | USB_DIR_IN)
2585 static int hub_set_address(struct usb_device *udev, int devnum)
2587 int retval;
2588 struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2591 * The host controller will choose the device address,
2592 * instead of the core having chosen it earlier
2594 if (!hcd->driver->address_device && devnum <= 1)
2595 return -EINVAL;
2596 if (udev->state == USB_STATE_ADDRESS)
2597 return 0;
2598 if (udev->state != USB_STATE_DEFAULT)
2599 return -EINVAL;
2600 if (hcd->driver->address_device)
2601 retval = hcd->driver->address_device(hcd, udev);
2602 else
2603 retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2604 USB_REQ_SET_ADDRESS, 0, devnum, 0,
2605 NULL, 0, USB_CTRL_SET_TIMEOUT);
2606 if (retval == 0) {
2607 update_address(udev, devnum);
2608 /* Device now using proper address. */
2609 usb_set_device_state(udev, USB_STATE_ADDRESS);
2610 usb_ep0_reinit(udev);
2612 return retval;
2615 /* Reset device, (re)assign address, get device descriptor.
2616 * Device connection must be stable, no more debouncing needed.
2617 * Returns device in USB_STATE_ADDRESS, except on error.
2619 * If this is called for an already-existing device (as part of
2620 * usb_reset_and_verify_device), the caller must own the device lock. For a
2621 * newly detected device that is not accessible through any global
2622 * pointers, it's not necessary to lock the device.
2624 static int
2625 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2626 int retry_counter)
2628 static DEFINE_MUTEX(usb_address0_mutex);
2630 struct usb_device *hdev = hub->hdev;
2631 struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
2632 int i, j, retval;
2633 unsigned delay = HUB_SHORT_RESET_TIME;
2634 enum usb_device_speed oldspeed = udev->speed;
2635 char *speed, *type;
2636 int devnum = udev->devnum;
2638 /* root hub ports have a slightly longer reset period
2639 * (from USB 2.0 spec, section 7.1.7.5)
2641 if (!hdev->parent) {
2642 delay = HUB_ROOT_RESET_TIME;
2643 if (port1 == hdev->bus->otg_port)
2644 hdev->bus->b_hnp_enable = 0;
2647 /* Some low speed devices have problems with the quick delay, so */
2648 /* be a bit pessimistic with those devices. RHbug #23670 */
2649 if (oldspeed == USB_SPEED_LOW)
2650 delay = HUB_LONG_RESET_TIME;
2652 mutex_lock(&usb_address0_mutex);
2654 if (!udev->config && oldspeed == USB_SPEED_SUPER) {
2655 /* Don't reset USB 3.0 devices during an initial setup */
2656 usb_set_device_state(udev, USB_STATE_DEFAULT);
2657 } else {
2658 /* Reset the device; full speed may morph to high speed */
2659 /* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */
2660 retval = hub_port_reset(hub, port1, udev, delay);
2661 if (retval < 0) /* error or disconnect */
2662 goto fail;
2663 /* success, speed is known */
2665 retval = -ENODEV;
2667 if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2668 dev_dbg(&udev->dev, "device reset changed speed!\n");
2669 goto fail;
2671 oldspeed = udev->speed;
2673 /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2674 * it's fixed size except for full speed devices.
2675 * For Wireless USB devices, ep0 max packet is always 512 (tho
2676 * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
2678 switch (udev->speed) {
2679 case USB_SPEED_SUPER:
2680 case USB_SPEED_WIRELESS: /* fixed at 512 */
2681 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
2682 break;
2683 case USB_SPEED_HIGH: /* fixed at 64 */
2684 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
2685 break;
2686 case USB_SPEED_FULL: /* 8, 16, 32, or 64 */
2687 /* to determine the ep0 maxpacket size, try to read
2688 * the device descriptor to get bMaxPacketSize0 and
2689 * then correct our initial guess.
2691 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
2692 break;
2693 case USB_SPEED_LOW: /* fixed at 8 */
2694 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(8);
2695 break;
2696 default:
2697 goto fail;
2700 type = "";
2701 switch (udev->speed) {
2702 case USB_SPEED_LOW: speed = "low"; break;
2703 case USB_SPEED_FULL: speed = "full"; break;
2704 case USB_SPEED_HIGH: speed = "high"; break;
2705 case USB_SPEED_SUPER:
2706 speed = "super";
2707 break;
2708 case USB_SPEED_WIRELESS:
2709 speed = "variable";
2710 type = "Wireless ";
2711 break;
2712 default: speed = "?"; break;
2714 if (udev->speed != USB_SPEED_SUPER)
2715 dev_info(&udev->dev,
2716 "%s %s speed %sUSB device using %s and address %d\n",
2717 (udev->config) ? "reset" : "new", speed, type,
2718 udev->bus->controller->driver->name, devnum);
2720 /* Set up TT records, if needed */
2721 if (hdev->tt) {
2722 udev->tt = hdev->tt;
2723 udev->ttport = hdev->ttport;
2724 } else if (udev->speed != USB_SPEED_HIGH
2725 && hdev->speed == USB_SPEED_HIGH) {
2726 if (!hub->tt.hub) {
2727 dev_err(&udev->dev, "parent hub has no TT\n");
2728 retval = -EINVAL;
2729 goto fail;
2731 udev->tt = &hub->tt;
2732 udev->ttport = port1;
2735 /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2736 * Because device hardware and firmware is sometimes buggy in
2737 * this area, and this is how Linux has done it for ages.
2738 * Change it cautiously.
2740 * NOTE: If USE_NEW_SCHEME() is true we will start by issuing
2741 * a 64-byte GET_DESCRIPTOR request. This is what Windows does,
2742 * so it may help with some non-standards-compliant devices.
2743 * Otherwise we start with SET_ADDRESS and then try to read the
2744 * first 8 bytes of the device descriptor to get the ep0 maxpacket
2745 * value.
2747 for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2749 * An xHCI controller cannot send any packets to a device until
2750 * a set address command successfully completes.
2752 if (USE_NEW_SCHEME(retry_counter) && !(hcd->driver->flags & HCD_USB3)) {
2753 struct usb_device_descriptor *buf;
2754 int r = 0;
2756 #define GET_DESCRIPTOR_BUFSIZE 64
2757 buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2758 if (!buf) {
2759 retval = -ENOMEM;
2760 continue;
2763 /* Retry on all errors; some devices are flakey.
2764 * 255 is for WUSB devices, we actually need to use
2765 * 512 (WUSB1.0[4.8.1]).
2767 for (j = 0; j < 3; ++j) {
2768 buf->bMaxPacketSize0 = 0;
2769 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2770 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2771 USB_DT_DEVICE << 8, 0,
2772 buf, GET_DESCRIPTOR_BUFSIZE,
2773 initial_descriptor_timeout);
2774 switch (buf->bMaxPacketSize0) {
2775 case 8: case 16: case 32: case 64: case 255:
2776 if (buf->bDescriptorType ==
2777 USB_DT_DEVICE) {
2778 r = 0;
2779 break;
2781 /* FALL THROUGH */
2782 default:
2783 if (r == 0)
2784 r = -EPROTO;
2785 break;
2787 if (r == 0)
2788 break;
2790 udev->descriptor.bMaxPacketSize0 =
2791 buf->bMaxPacketSize0;
2792 kfree(buf);
2794 retval = hub_port_reset(hub, port1, udev, delay);
2795 if (retval < 0) /* error or disconnect */
2796 goto fail;
2797 if (oldspeed != udev->speed) {
2798 dev_dbg(&udev->dev,
2799 "device reset changed speed!\n");
2800 retval = -ENODEV;
2801 goto fail;
2803 if (r) {
2804 dev_err(&udev->dev,
2805 "device descriptor read/64, error %d\n",
2807 retval = -EMSGSIZE;
2808 continue;
2810 #undef GET_DESCRIPTOR_BUFSIZE
2814 * If device is WUSB, we already assigned an
2815 * unauthorized address in the Connect Ack sequence;
2816 * authorization will assign the final address.
2818 if (udev->wusb == 0) {
2819 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2820 retval = hub_set_address(udev, devnum);
2821 if (retval >= 0)
2822 break;
2823 msleep(200);
2825 if (retval < 0) {
2826 dev_err(&udev->dev,
2827 "device not accepting address %d, error %d\n",
2828 devnum, retval);
2829 goto fail;
2831 if (udev->speed == USB_SPEED_SUPER) {
2832 devnum = udev->devnum;
2833 dev_info(&udev->dev,
2834 "%s SuperSpeed USB device using %s and address %d\n",
2835 (udev->config) ? "reset" : "new",
2836 udev->bus->controller->driver->name, devnum);
2839 /* cope with hardware quirkiness:
2840 * - let SET_ADDRESS settle, some device hardware wants it
2841 * - read ep0 maxpacket even for high and low speed,
2843 msleep(10);
2844 if (USE_NEW_SCHEME(retry_counter) && !(hcd->driver->flags & HCD_USB3))
2845 break;
2848 retval = usb_get_device_descriptor(udev, 8);
2849 if (retval < 8) {
2850 dev_err(&udev->dev,
2851 "device descriptor read/8, error %d\n",
2852 retval);
2853 if (retval >= 0)
2854 retval = -EMSGSIZE;
2855 } else {
2856 retval = 0;
2857 break;
2860 if (retval)
2861 goto fail;
2863 if (udev->descriptor.bMaxPacketSize0 == 0xff ||
2864 udev->speed == USB_SPEED_SUPER)
2865 i = 512;
2866 else
2867 i = udev->descriptor.bMaxPacketSize0;
2868 if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2869 if (udev->speed == USB_SPEED_LOW ||
2870 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2871 dev_err(&udev->dev, "Invalid ep0 maxpacket: %d\n", i);
2872 retval = -EMSGSIZE;
2873 goto fail;
2875 if (udev->speed == USB_SPEED_FULL)
2876 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2877 else
2878 dev_warn(&udev->dev, "Using ep0 maxpacket: %d\n", i);
2879 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2880 usb_ep0_reinit(udev);
2883 retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2884 if (retval < (signed)sizeof(udev->descriptor)) {
2885 dev_err(&udev->dev, "device descriptor read/all, error %d\n",
2886 retval);
2887 if (retval >= 0)
2888 retval = -ENOMSG;
2889 goto fail;
2892 retval = 0;
2893 /* notify HCD that we have a device connected and addressed */
2894 if (hcd->driver->update_device)
2895 hcd->driver->update_device(hcd, udev);
2896 fail:
2897 if (retval) {
2898 hub_port_disable(hub, port1, 0);
2899 update_address(udev, devnum); /* for disconnect processing */
2901 mutex_unlock(&usb_address0_mutex);
2902 return retval;
2905 static void
2906 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2908 struct usb_qualifier_descriptor *qual;
2909 int status;
2911 qual = kmalloc (sizeof *qual, GFP_KERNEL);
2912 if (qual == NULL)
2913 return;
2915 status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2916 qual, sizeof *qual);
2917 if (status == sizeof *qual) {
2918 dev_info(&udev->dev, "not running at top speed; "
2919 "connect to a high speed hub\n");
2920 /* hub LEDs are probably harder to miss than syslog */
2921 if (hub->has_indicators) {
2922 hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2923 schedule_delayed_work (&hub->leds, 0);
2926 kfree(qual);
2929 static unsigned
2930 hub_power_remaining (struct usb_hub *hub)
2932 struct usb_device *hdev = hub->hdev;
2933 int remaining;
2934 int port1;
2936 if (!hub->limited_power)
2937 return 0;
2939 remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
2940 for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
2941 struct usb_device *udev = hdev->children[port1 - 1];
2942 int delta;
2944 if (!udev)
2945 continue;
2947 /* Unconfigured devices may not use more than 100mA,
2948 * or 8mA for OTG ports */
2949 if (udev->actconfig)
2950 delta = udev->actconfig->desc.bMaxPower * 2;
2951 else if (port1 != udev->bus->otg_port || hdev->parent)
2952 delta = 100;
2953 else
2954 delta = 8;
2955 if (delta > hub->mA_per_port)
2956 dev_warn(&udev->dev,
2957 "%dmA is over %umA budget for port %d!\n",
2958 delta, hub->mA_per_port, port1);
2959 remaining -= delta;
2961 if (remaining < 0) {
2962 dev_warn(hub->intfdev, "%dmA over power budget!\n",
2963 - remaining);
2964 remaining = 0;
2966 return remaining;
2969 /* Handle physical or logical connection change events.
2970 * This routine is called when:
2971 * a port connection-change occurs;
2972 * a port enable-change occurs (often caused by EMI);
2973 * usb_reset_and_verify_device() encounters changed descriptors (as from
2974 * a firmware download)
2975 * caller already locked the hub
2977 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2978 u16 portstatus, u16 portchange)
2980 struct usb_device *hdev = hub->hdev;
2981 struct device *hub_dev = hub->intfdev;
2982 struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
2983 unsigned wHubCharacteristics =
2984 le16_to_cpu(hub->descriptor->wHubCharacteristics);
2985 struct usb_device *udev;
2986 int status, i;
2988 dev_dbg (hub_dev,
2989 "port %d, status %04x, change %04x, %s\n",
2990 port1, portstatus, portchange, portspeed (portstatus));
2992 if (hub->has_indicators) {
2993 set_port_led(hub, port1, HUB_LED_AUTO);
2994 hub->indicator[port1-1] = INDICATOR_AUTO;
2997 #ifdef CONFIG_USB_OTG
2998 /* during HNP, don't repeat the debounce */
2999 if (hdev->bus->is_b_host)
3000 portchange &= ~(USB_PORT_STAT_C_CONNECTION |
3001 USB_PORT_STAT_C_ENABLE);
3002 #endif
3004 /* Try to resuscitate an existing device */
3005 udev = hdev->children[port1-1];
3006 if ((portstatus & USB_PORT_STAT_CONNECTION) && udev &&
3007 udev->state != USB_STATE_NOTATTACHED) {
3008 usb_lock_device(udev);
3009 if (portstatus & USB_PORT_STAT_ENABLE) {
3010 status = 0; /* Nothing to do */
3012 #ifdef CONFIG_USB_SUSPEND
3013 } else if (udev->state == USB_STATE_SUSPENDED &&
3014 udev->persist_enabled) {
3015 /* For a suspended device, treat this as a
3016 * remote wakeup event.
3018 status = usb_remote_wakeup(udev);
3019 #endif
3021 } else {
3022 status = -ENODEV; /* Don't resuscitate */
3024 usb_unlock_device(udev);
3026 if (status == 0) {
3027 clear_bit(port1, hub->change_bits);
3028 return;
3032 /* Disconnect any existing devices under this port */
3033 if (udev)
3034 usb_disconnect(&hdev->children[port1-1]);
3035 clear_bit(port1, hub->change_bits);
3037 /* We can forget about a "removed" device when there's a physical
3038 * disconnect or the connect status changes.
3040 if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
3041 (portchange & USB_PORT_STAT_C_CONNECTION))
3042 clear_bit(port1, hub->removed_bits);
3044 if (portchange & (USB_PORT_STAT_C_CONNECTION |
3045 USB_PORT_STAT_C_ENABLE)) {
3046 status = hub_port_debounce(hub, port1);
3047 if (status < 0) {
3048 if (printk_ratelimit())
3049 dev_err(hub_dev, "connect-debounce failed, "
3050 "port %d disabled\n", port1);
3051 portstatus &= ~USB_PORT_STAT_CONNECTION;
3052 } else {
3053 portstatus = status;
3057 /* Return now if debouncing failed or nothing is connected or
3058 * the device was "removed".
3060 if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
3061 test_bit(port1, hub->removed_bits)) {
3063 /* maybe switch power back on (e.g. root hub was reset) */
3064 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
3065 && !(portstatus & USB_PORT_STAT_POWER))
3066 set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
3068 if (portstatus & USB_PORT_STAT_ENABLE)
3069 goto done;
3070 return;
3073 for (i = 0; i < SET_CONFIG_TRIES; i++) {
3075 /* reallocate for each attempt, since references
3076 * to the previous one can escape in various ways
3078 udev = usb_alloc_dev(hdev, hdev->bus, port1);
3079 if (!udev) {
3080 dev_err (hub_dev,
3081 "couldn't allocate port %d usb_device\n",
3082 port1);
3083 goto done;
3086 usb_set_device_state(udev, USB_STATE_POWERED);
3087 udev->bus_mA = hub->mA_per_port;
3088 udev->level = hdev->level + 1;
3089 udev->wusb = hub_is_wusb(hub);
3092 * USB 3.0 devices are reset automatically before the connect
3093 * port status change appears, and the root hub port status
3094 * shows the correct speed. We also get port change
3095 * notifications for USB 3.0 devices from the USB 3.0 portion of
3096 * an external USB 3.0 hub, but this isn't handled correctly yet
3097 * FIXME.
3100 if (!(hcd->driver->flags & HCD_USB3))
3101 udev->speed = USB_SPEED_UNKNOWN;
3102 else if ((hdev->parent == NULL) &&
3103 (portstatus & USB_PORT_STAT_SUPER_SPEED))
3104 udev->speed = USB_SPEED_SUPER;
3105 else
3106 udev->speed = USB_SPEED_UNKNOWN;
3109 * Set the address.
3110 * Note xHCI needs to issue an address device command later
3111 * in the hub_port_init sequence for SS/HS/FS/LS devices,
3112 * and xHC will assign an address to the device. But use
3113 * kernel assigned address here, to avoid any address conflict
3114 * issue.
3116 choose_address(udev);
3117 if (udev->devnum <= 0) {
3118 status = -ENOTCONN; /* Don't retry */
3119 goto loop;
3122 /* reset (non-USB 3.0 devices) and get descriptor */
3123 status = hub_port_init(hub, udev, port1, i);
3124 if (status < 0)
3125 goto loop;
3127 usb_detect_quirks(udev);
3128 if (udev->quirks & USB_QUIRK_DELAY_INIT)
3129 msleep(1000);
3131 /* consecutive bus-powered hubs aren't reliable; they can
3132 * violate the voltage drop budget. if the new child has
3133 * a "powered" LED, users should notice we didn't enable it
3134 * (without reading syslog), even without per-port LEDs
3135 * on the parent.
3137 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
3138 && udev->bus_mA <= 100) {
3139 u16 devstat;
3141 status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
3142 &devstat);
3143 if (status < 2) {
3144 dev_dbg(&udev->dev, "get status %d ?\n", status);
3145 goto loop_disable;
3147 le16_to_cpus(&devstat);
3148 if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
3149 dev_err(&udev->dev,
3150 "can't connect bus-powered hub "
3151 "to this port\n");
3152 if (hub->has_indicators) {
3153 hub->indicator[port1-1] =
3154 INDICATOR_AMBER_BLINK;
3155 schedule_delayed_work (&hub->leds, 0);
3157 status = -ENOTCONN; /* Don't retry */
3158 goto loop_disable;
3162 /* check for devices running slower than they could */
3163 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
3164 && udev->speed == USB_SPEED_FULL
3165 && highspeed_hubs != 0)
3166 check_highspeed (hub, udev, port1);
3168 /* Store the parent's children[] pointer. At this point
3169 * udev becomes globally accessible, although presumably
3170 * no one will look at it until hdev is unlocked.
3172 status = 0;
3174 /* We mustn't add new devices if the parent hub has
3175 * been disconnected; we would race with the
3176 * recursively_mark_NOTATTACHED() routine.
3178 spin_lock_irq(&device_state_lock);
3179 if (hdev->state == USB_STATE_NOTATTACHED)
3180 status = -ENOTCONN;
3181 else
3182 hdev->children[port1-1] = udev;
3183 spin_unlock_irq(&device_state_lock);
3185 /* Run it through the hoops (find a driver, etc) */
3186 if (!status) {
3187 status = usb_new_device(udev);
3188 if (status) {
3189 spin_lock_irq(&device_state_lock);
3190 hdev->children[port1-1] = NULL;
3191 spin_unlock_irq(&device_state_lock);
3195 if (status)
3196 goto loop_disable;
3198 status = hub_power_remaining(hub);
3199 if (status)
3200 dev_dbg(hub_dev, "%dmA power budget left\n", status);
3202 return;
3204 loop_disable:
3205 hub_port_disable(hub, port1, 1);
3206 loop:
3207 usb_ep0_reinit(udev);
3208 release_address(udev);
3209 hub_free_dev(udev);
3210 usb_put_dev(udev);
3211 if ((status == -ENOTCONN) || (status == -ENOTSUPP))
3212 break;
3214 if (hub->hdev->parent ||
3215 !hcd->driver->port_handed_over ||
3216 !(hcd->driver->port_handed_over)(hcd, port1))
3217 dev_err(hub_dev, "unable to enumerate USB device on port %d\n",
3218 port1);
3220 done:
3221 hub_port_disable(hub, port1, 1);
3222 if (hcd->driver->relinquish_port && !hub->hdev->parent)
3223 hcd->driver->relinquish_port(hcd, port1);
3226 static void hub_events(void)
3228 struct list_head *tmp;
3229 struct usb_device *hdev;
3230 struct usb_interface *intf;
3231 struct usb_hub *hub;
3232 struct device *hub_dev;
3233 u16 hubstatus;
3234 u16 hubchange;
3235 u16 portstatus;
3236 u16 portchange;
3237 int i, ret;
3238 int connect_change;
3241 * We restart the list every time to avoid a deadlock with
3242 * deleting hubs downstream from this one. This should be
3243 * safe since we delete the hub from the event list.
3244 * Not the most efficient, but avoids deadlocks.
3246 while (1) {
3248 /* Grab the first entry at the beginning of the list */
3249 spin_lock_irq(&hub_event_lock);
3250 if (list_empty(&hub_event_list)) {
3251 spin_unlock_irq(&hub_event_lock);
3252 break;
3255 tmp = hub_event_list.next;
3256 list_del_init(tmp);
3258 hub = list_entry(tmp, struct usb_hub, event_list);
3259 kref_get(&hub->kref);
3260 spin_unlock_irq(&hub_event_lock);
3262 hdev = hub->hdev;
3263 hub_dev = hub->intfdev;
3264 intf = to_usb_interface(hub_dev);
3265 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
3266 hdev->state, hub->descriptor
3267 ? hub->descriptor->bNbrPorts
3268 : 0,
3269 /* NOTE: expects max 15 ports... */
3270 (u16) hub->change_bits[0],
3271 (u16) hub->event_bits[0]);
3273 /* Lock the device, then check to see if we were
3274 * disconnected while waiting for the lock to succeed. */
3275 usb_lock_device(hdev);
3276 if (unlikely(hub->disconnected))
3277 goto loop_disconnected;
3279 /* If the hub has died, clean up after it */
3280 if (hdev->state == USB_STATE_NOTATTACHED) {
3281 hub->error = -ENODEV;
3282 hub_quiesce(hub, HUB_DISCONNECT);
3283 goto loop;
3286 /* Autoresume */
3287 ret = usb_autopm_get_interface(intf);
3288 if (ret) {
3289 dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
3290 goto loop;
3293 /* If this is an inactive hub, do nothing */
3294 if (hub->quiescing)
3295 goto loop_autopm;
3297 if (hub->error) {
3298 dev_dbg (hub_dev, "resetting for error %d\n",
3299 hub->error);
3301 ret = usb_reset_device(hdev);
3302 if (ret) {
3303 dev_dbg (hub_dev,
3304 "error resetting hub: %d\n", ret);
3305 goto loop_autopm;
3308 hub->nerrors = 0;
3309 hub->error = 0;
3312 /* deal with port status changes */
3313 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
3314 if (test_bit(i, hub->busy_bits))
3315 continue;
3316 connect_change = test_bit(i, hub->change_bits);
3317 if (!test_and_clear_bit(i, hub->event_bits) &&
3318 !connect_change)
3319 continue;
3321 ret = hub_port_status(hub, i,
3322 &portstatus, &portchange);
3323 if (ret < 0)
3324 continue;
3326 if (portchange & USB_PORT_STAT_C_CONNECTION) {
3327 clear_port_feature(hdev, i,
3328 USB_PORT_FEAT_C_CONNECTION);
3329 connect_change = 1;
3332 if (portchange & USB_PORT_STAT_C_ENABLE) {
3333 if (!connect_change)
3334 dev_dbg (hub_dev,
3335 "port %d enable change, "
3336 "status %08x\n",
3337 i, portstatus);
3338 clear_port_feature(hdev, i,
3339 USB_PORT_FEAT_C_ENABLE);
3342 * EM interference sometimes causes badly
3343 * shielded USB devices to be shutdown by
3344 * the hub, this hack enables them again.
3345 * Works at least with mouse driver.
3347 if (!(portstatus & USB_PORT_STAT_ENABLE)
3348 && !connect_change
3349 && hdev->children[i-1]) {
3350 dev_err (hub_dev,
3351 "port %i "
3352 "disabled by hub (EMI?), "
3353 "re-enabling...\n",
3355 connect_change = 1;
3359 if (portchange & USB_PORT_STAT_C_SUSPEND) {
3360 struct usb_device *udev;
3362 clear_port_feature(hdev, i,
3363 USB_PORT_FEAT_C_SUSPEND);
3364 udev = hdev->children[i-1];
3365 if (udev) {
3366 /* TRSMRCY = 10 msec */
3367 msleep(10);
3369 usb_lock_device(udev);
3370 ret = usb_remote_wakeup(hdev->
3371 children[i-1]);
3372 usb_unlock_device(udev);
3373 if (ret < 0)
3374 connect_change = 1;
3375 } else {
3376 ret = -ENODEV;
3377 hub_port_disable(hub, i, 1);
3379 dev_dbg (hub_dev,
3380 "resume on port %d, status %d\n",
3381 i, ret);
3384 if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
3385 dev_err (hub_dev,
3386 "over-current change on port %d\n",
3388 clear_port_feature(hdev, i,
3389 USB_PORT_FEAT_C_OVER_CURRENT);
3390 hub_power_on(hub, true);
3393 if (portchange & USB_PORT_STAT_C_RESET) {
3394 dev_dbg (hub_dev,
3395 "reset change on port %d\n",
3397 clear_port_feature(hdev, i,
3398 USB_PORT_FEAT_C_RESET);
3401 if (connect_change)
3402 hub_port_connect_change(hub, i,
3403 portstatus, portchange);
3404 } /* end for i */
3406 /* deal with hub status changes */
3407 if (test_and_clear_bit(0, hub->event_bits) == 0)
3408 ; /* do nothing */
3409 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
3410 dev_err (hub_dev, "get_hub_status failed\n");
3411 else {
3412 if (hubchange & HUB_CHANGE_LOCAL_POWER) {
3413 dev_dbg (hub_dev, "power change\n");
3414 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
3415 if (hubstatus & HUB_STATUS_LOCAL_POWER)
3416 /* FIXME: Is this always true? */
3417 hub->limited_power = 1;
3418 else
3419 hub->limited_power = 0;
3421 if (hubchange & HUB_CHANGE_OVERCURRENT) {
3422 dev_dbg (hub_dev, "overcurrent change\n");
3423 msleep(500); /* Cool down */
3424 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
3425 hub_power_on(hub, true);
3429 loop_autopm:
3430 /* Balance the usb_autopm_get_interface() above */
3431 usb_autopm_put_interface_no_suspend(intf);
3432 loop:
3433 /* Balance the usb_autopm_get_interface_no_resume() in
3434 * kick_khubd() and allow autosuspend.
3436 usb_autopm_put_interface(intf);
3437 loop_disconnected:
3438 usb_unlock_device(hdev);
3439 kref_put(&hub->kref, hub_release);
3441 } /* end while (1) */
3444 static int hub_thread(void *__unused)
3446 /* khubd needs to be freezable to avoid intefering with USB-PERSIST
3447 * port handover. Otherwise it might see that a full-speed device
3448 * was gone before the EHCI controller had handed its port over to
3449 * the companion full-speed controller.
3451 set_freezable();
3453 do {
3454 hub_events();
3455 wait_event_freezable(khubd_wait,
3456 !list_empty(&hub_event_list) ||
3457 kthread_should_stop());
3458 } while (!kthread_should_stop() || !list_empty(&hub_event_list));
3460 pr_debug("%s: khubd exiting\n", usbcore_name);
3461 return 0;
3464 static const struct usb_device_id hub_id_table[] = {
3465 { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
3466 .bDeviceClass = USB_CLASS_HUB},
3467 { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
3468 .bInterfaceClass = USB_CLASS_HUB},
3469 { } /* Terminating entry */
3472 MODULE_DEVICE_TABLE (usb, hub_id_table);
3474 static struct usb_driver hub_driver = {
3475 .name = "hub",
3476 .probe = hub_probe,
3477 .disconnect = hub_disconnect,
3478 .suspend = hub_suspend,
3479 .resume = hub_resume,
3480 .reset_resume = hub_reset_resume,
3481 .pre_reset = hub_pre_reset,
3482 .post_reset = hub_post_reset,
3483 .unlocked_ioctl = hub_ioctl,
3484 .id_table = hub_id_table,
3485 .supports_autosuspend = 1,
3488 int usb_hub_init(void)
3490 if (usb_register(&hub_driver) < 0) {
3491 printk(KERN_ERR "%s: can't register hub driver\n",
3492 usbcore_name);
3493 return -1;
3496 khubd_task = kthread_run(hub_thread, NULL, "khubd");
3497 if (!IS_ERR(khubd_task))
3498 return 0;
3500 /* Fall through if kernel_thread failed */
3501 usb_deregister(&hub_driver);
3502 printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
3504 return -1;
3507 void usb_hub_cleanup(void)
3509 kthread_stop(khubd_task);
3512 * Hub resources are freed for us by usb_deregister. It calls
3513 * usb_driver_purge on every device which in turn calls that
3514 * devices disconnect function if it is using this driver.
3515 * The hub_disconnect function takes care of releasing the
3516 * individual hub resources. -greg
3518 usb_deregister(&hub_driver);
3519 } /* usb_hub_cleanup() */
3521 static int descriptors_changed(struct usb_device *udev,
3522 struct usb_device_descriptor *old_device_descriptor)
3524 int changed = 0;
3525 unsigned index;
3526 unsigned serial_len = 0;
3527 unsigned len;
3528 unsigned old_length;
3529 int length;
3530 char *buf;
3532 if (memcmp(&udev->descriptor, old_device_descriptor,
3533 sizeof(*old_device_descriptor)) != 0)
3534 return 1;
3536 /* Since the idVendor, idProduct, and bcdDevice values in the
3537 * device descriptor haven't changed, we will assume the
3538 * Manufacturer and Product strings haven't changed either.
3539 * But the SerialNumber string could be different (e.g., a
3540 * different flash card of the same brand).
3542 if (udev->serial)
3543 serial_len = strlen(udev->serial) + 1;
3545 len = serial_len;
3546 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
3547 old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
3548 len = max(len, old_length);
3551 buf = kmalloc(len, GFP_NOIO);
3552 if (buf == NULL) {
3553 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
3554 /* assume the worst */
3555 return 1;
3557 for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
3558 old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
3559 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
3560 old_length);
3561 if (length != old_length) {
3562 dev_dbg(&udev->dev, "config index %d, error %d\n",
3563 index, length);
3564 changed = 1;
3565 break;
3567 if (memcmp (buf, udev->rawdescriptors[index], old_length)
3568 != 0) {
3569 dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
3570 index,
3571 ((struct usb_config_descriptor *) buf)->
3572 bConfigurationValue);
3573 changed = 1;
3574 break;
3578 if (!changed && serial_len) {
3579 length = usb_string(udev, udev->descriptor.iSerialNumber,
3580 buf, serial_len);
3581 if (length + 1 != serial_len) {
3582 dev_dbg(&udev->dev, "serial string error %d\n",
3583 length);
3584 changed = 1;
3585 } else if (memcmp(buf, udev->serial, length) != 0) {
3586 dev_dbg(&udev->dev, "serial string changed\n");
3587 changed = 1;
3591 kfree(buf);
3592 return changed;
3596 * usb_reset_and_verify_device - perform a USB port reset to reinitialize a device
3597 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
3599 * WARNING - don't use this routine to reset a composite device
3600 * (one with multiple interfaces owned by separate drivers)!
3601 * Use usb_reset_device() instead.
3603 * Do a port reset, reassign the device's address, and establish its
3604 * former operating configuration. If the reset fails, or the device's
3605 * descriptors change from their values before the reset, or the original
3606 * configuration and altsettings cannot be restored, a flag will be set
3607 * telling khubd to pretend the device has been disconnected and then
3608 * re-connected. All drivers will be unbound, and the device will be
3609 * re-enumerated and probed all over again.
3611 * Returns 0 if the reset succeeded, -ENODEV if the device has been
3612 * flagged for logical disconnection, or some other negative error code
3613 * if the reset wasn't even attempted.
3615 * The caller must own the device lock. For example, it's safe to use
3616 * this from a driver probe() routine after downloading new firmware.
3617 * For calls that might not occur during probe(), drivers should lock
3618 * the device using usb_lock_device_for_reset().
3620 * Locking exception: This routine may also be called from within an
3621 * autoresume handler. Such usage won't conflict with other tasks
3622 * holding the device lock because these tasks should always call
3623 * usb_autopm_resume_device(), thereby preventing any unwanted autoresume.
3625 static int usb_reset_and_verify_device(struct usb_device *udev)
3627 struct usb_device *parent_hdev = udev->parent;
3628 struct usb_hub *parent_hub;
3629 struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3630 struct usb_device_descriptor descriptor = udev->descriptor;
3631 int i, ret = 0;
3632 int port1 = udev->portnum;
3634 if (udev->state == USB_STATE_NOTATTACHED ||
3635 udev->state == USB_STATE_SUSPENDED) {
3636 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3637 udev->state);
3638 return -EINVAL;
3641 if (!parent_hdev) {
3642 /* this requires hcd-specific logic; see ohci_restart() */
3643 dev_dbg(&udev->dev, "%s for root hub!\n", __func__);
3644 return -EISDIR;
3646 parent_hub = hdev_to_hub(parent_hdev);
3648 set_bit(port1, parent_hub->busy_bits);
3649 for (i = 0; i < SET_CONFIG_TRIES; ++i) {
3651 /* ep0 maxpacket size may change; let the HCD know about it.
3652 * Other endpoints will be handled by re-enumeration. */
3653 usb_ep0_reinit(udev);
3654 ret = hub_port_init(parent_hub, udev, port1, i);
3655 if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
3656 break;
3658 clear_bit(port1, parent_hub->busy_bits);
3660 if (ret < 0)
3661 goto re_enumerate;
3663 /* Device might have changed firmware (DFU or similar) */
3664 if (descriptors_changed(udev, &descriptor)) {
3665 dev_info(&udev->dev, "device firmware changed\n");
3666 udev->descriptor = descriptor; /* for disconnect() calls */
3667 goto re_enumerate;
3670 /* Restore the device's previous configuration */
3671 if (!udev->actconfig)
3672 goto done;
3674 mutex_lock(&hcd->bandwidth_mutex);
3675 ret = usb_hcd_alloc_bandwidth(udev, udev->actconfig, NULL, NULL);
3676 if (ret < 0) {
3677 dev_warn(&udev->dev,
3678 "Busted HC? Not enough HCD resources for "
3679 "old configuration.\n");
3680 mutex_unlock(&hcd->bandwidth_mutex);
3681 goto re_enumerate;
3683 ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3684 USB_REQ_SET_CONFIGURATION, 0,
3685 udev->actconfig->desc.bConfigurationValue, 0,
3686 NULL, 0, USB_CTRL_SET_TIMEOUT);
3687 if (ret < 0) {
3688 dev_err(&udev->dev,
3689 "can't restore configuration #%d (error=%d)\n",
3690 udev->actconfig->desc.bConfigurationValue, ret);
3691 mutex_unlock(&hcd->bandwidth_mutex);
3692 goto re_enumerate;
3694 mutex_unlock(&hcd->bandwidth_mutex);
3695 usb_set_device_state(udev, USB_STATE_CONFIGURED);
3697 /* Put interfaces back into the same altsettings as before.
3698 * Don't bother to send the Set-Interface request for interfaces
3699 * that were already in altsetting 0; besides being unnecessary,
3700 * many devices can't handle it. Instead just reset the host-side
3701 * endpoint state.
3703 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3704 struct usb_host_config *config = udev->actconfig;
3705 struct usb_interface *intf = config->interface[i];
3706 struct usb_interface_descriptor *desc;
3708 desc = &intf->cur_altsetting->desc;
3709 if (desc->bAlternateSetting == 0) {
3710 usb_disable_interface(udev, intf, true);
3711 usb_enable_interface(udev, intf, true);
3712 ret = 0;
3713 } else {
3714 /* Let the bandwidth allocation function know that this
3715 * device has been reset, and it will have to use
3716 * alternate setting 0 as the current alternate setting.
3718 intf->resetting_device = 1;
3719 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3720 desc->bAlternateSetting);
3721 intf->resetting_device = 0;
3723 if (ret < 0) {
3724 dev_err(&udev->dev, "failed to restore interface %d "
3725 "altsetting %d (error=%d)\n",
3726 desc->bInterfaceNumber,
3727 desc->bAlternateSetting,
3728 ret);
3729 goto re_enumerate;
3733 done:
3734 return 0;
3736 re_enumerate:
3737 hub_port_logical_disconnect(parent_hub, port1);
3738 return -ENODEV;
3742 * usb_reset_device - warn interface drivers and perform a USB port reset
3743 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
3745 * Warns all drivers bound to registered interfaces (using their pre_reset
3746 * method), performs the port reset, and then lets the drivers know that
3747 * the reset is over (using their post_reset method).
3749 * Return value is the same as for usb_reset_and_verify_device().
3751 * The caller must own the device lock. For example, it's safe to use
3752 * this from a driver probe() routine after downloading new firmware.
3753 * For calls that might not occur during probe(), drivers should lock
3754 * the device using usb_lock_device_for_reset().
3756 * If an interface is currently being probed or disconnected, we assume
3757 * its driver knows how to handle resets. For all other interfaces,
3758 * if the driver doesn't have pre_reset and post_reset methods then
3759 * we attempt to unbind it and rebind afterward.
3761 int usb_reset_device(struct usb_device *udev)
3763 int ret;
3764 int i;
3765 struct usb_host_config *config = udev->actconfig;
3767 if (udev->state == USB_STATE_NOTATTACHED ||
3768 udev->state == USB_STATE_SUSPENDED) {
3769 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3770 udev->state);
3771 return -EINVAL;
3774 /* Prevent autosuspend during the reset */
3775 usb_autoresume_device(udev);
3777 if (config) {
3778 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
3779 struct usb_interface *cintf = config->interface[i];
3780 struct usb_driver *drv;
3781 int unbind = 0;
3783 if (cintf->dev.driver) {
3784 drv = to_usb_driver(cintf->dev.driver);
3785 if (drv->pre_reset && drv->post_reset)
3786 unbind = (drv->pre_reset)(cintf);
3787 else if (cintf->condition ==
3788 USB_INTERFACE_BOUND)
3789 unbind = 1;
3790 if (unbind)
3791 usb_forced_unbind_intf(cintf);
3796 ret = usb_reset_and_verify_device(udev);
3798 if (config) {
3799 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
3800 struct usb_interface *cintf = config->interface[i];
3801 struct usb_driver *drv;
3802 int rebind = cintf->needs_binding;
3804 if (!rebind && cintf->dev.driver) {
3805 drv = to_usb_driver(cintf->dev.driver);
3806 if (drv->post_reset)
3807 rebind = (drv->post_reset)(cintf);
3808 else if (cintf->condition ==
3809 USB_INTERFACE_BOUND)
3810 rebind = 1;
3812 if (ret == 0 && rebind)
3813 usb_rebind_intf(cintf);
3817 usb_autosuspend_device(udev);
3818 return ret;
3820 EXPORT_SYMBOL_GPL(usb_reset_device);
3824 * usb_queue_reset_device - Reset a USB device from an atomic context
3825 * @iface: USB interface belonging to the device to reset
3827 * This function can be used to reset a USB device from an atomic
3828 * context, where usb_reset_device() won't work (as it blocks).
3830 * Doing a reset via this method is functionally equivalent to calling
3831 * usb_reset_device(), except for the fact that it is delayed to a
3832 * workqueue. This means that any drivers bound to other interfaces
3833 * might be unbound, as well as users from usbfs in user space.
3835 * Corner cases:
3837 * - Scheduling two resets at the same time from two different drivers
3838 * attached to two different interfaces of the same device is
3839 * possible; depending on how the driver attached to each interface
3840 * handles ->pre_reset(), the second reset might happen or not.
3842 * - If a driver is unbound and it had a pending reset, the reset will
3843 * be cancelled.
3845 * - This function can be called during .probe() or .disconnect()
3846 * times. On return from .disconnect(), any pending resets will be
3847 * cancelled.
3849 * There is no no need to lock/unlock the @reset_ws as schedule_work()
3850 * does its own.
3852 * NOTE: We don't do any reference count tracking because it is not
3853 * needed. The lifecycle of the work_struct is tied to the
3854 * usb_interface. Before destroying the interface we cancel the
3855 * work_struct, so the fact that work_struct is queued and or
3856 * running means the interface (and thus, the device) exist and
3857 * are referenced.
3859 void usb_queue_reset_device(struct usb_interface *iface)
3861 schedule_work(&iface->reset_ws);
3863 EXPORT_SYMBOL_GPL(usb_queue_reset_device);