4 * This driver supports USB CDC WCM Device Management.
6 * Copyright (c) 2007-2009 Oliver Neukum
8 * Some code taken from cdc-acm.c
10 * Released under the GPLv2.
12 * Many thanks to Carl Nordbeck
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/slab.h>
17 #include <linux/module.h>
18 #include <linux/mutex.h>
19 #include <linux/uaccess.h>
20 #include <linux/bitops.h>
21 #include <linux/poll.h>
22 #include <linux/usb.h>
23 #include <linux/usb/cdc.h>
24 #include <asm/byteorder.h>
25 #include <asm/unaligned.h>
26 #include <linux/usb/cdc-wdm.h>
31 #define DRIVER_VERSION "v0.03"
32 #define DRIVER_AUTHOR "Oliver Neukum"
33 #define DRIVER_DESC "USB Abstract Control Model driver for USB WCM Device Management"
35 #define HUAWEI_VENDOR_ID 0x12D1
37 static const struct usb_device_id wdm_ids[] = {
39 .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS |
40 USB_DEVICE_ID_MATCH_INT_SUBCLASS,
41 .bInterfaceClass = USB_CLASS_COMM,
42 .bInterfaceSubClass = USB_CDC_SUBCLASS_DMM
46 * Huawei E392, E398 and possibly other Qualcomm based modems
47 * embed the Qualcomm QMI protocol inside CDC on CDC ECM like
48 * control interfaces. Userspace access to this is required
49 * to configure the accompanying data interface
51 .match_flags = USB_DEVICE_ID_MATCH_VENDOR |
52 USB_DEVICE_ID_MATCH_INT_INFO,
53 .idVendor = HUAWEI_VENDOR_ID,
54 .bInterfaceClass = USB_CLASS_VENDOR_SPEC,
55 .bInterfaceSubClass = 1,
56 .bInterfaceProtocol = 9, /* NOTE: CDC ECM control interface! */
61 MODULE_DEVICE_TABLE (usb, wdm_ids);
63 #define WDM_MINOR_BASE 176
67 #define WDM_DISCONNECTING 2
70 #define WDM_INT_STALL 5
71 #define WDM_POLL_RUNNING 6
72 #define WDM_RESPONDING 7
73 #define WDM_SUSPENDING 8
74 #define WDM_RESETTING 9
78 /* CDC-WMC r1.1 requires wMaxCommand to be "at least 256 decimal (0x100)" */
79 #define WDM_DEFAULT_BUFSIZE 256
81 static DEFINE_MUTEX(wdm_mutex);
82 static DEFINE_SPINLOCK(wdm_device_list_lock);
83 static LIST_HEAD(wdm_device_list);
85 /* --- method tables --- */
88 u8 *inbuf; /* buffer for response */
89 u8 *outbuf; /* buffer for command */
90 u8 *sbuf; /* buffer for status */
91 u8 *ubuf; /* buffer for copy to user space */
96 struct usb_interface *intf;
97 struct usb_ctrlrequest *orq;
98 struct usb_ctrlrequest *irq;
114 wait_queue_head_t wait;
115 struct work_struct rxwork;
119 struct list_head device_list;
120 int (*manage_power)(struct usb_interface *, int);
123 static struct usb_driver wdm_driver;
125 /* return intfdata if we own the interface, else look up intf in the list */
126 static struct wdm_device *wdm_find_device(struct usb_interface *intf)
128 struct wdm_device *desc = NULL;
130 spin_lock(&wdm_device_list_lock);
131 list_for_each_entry(desc, &wdm_device_list, device_list)
132 if (desc->intf == intf)
134 spin_unlock(&wdm_device_list_lock);
139 static struct wdm_device *wdm_find_device_by_minor(int minor)
141 struct wdm_device *desc = NULL;
143 spin_lock(&wdm_device_list_lock);
144 list_for_each_entry(desc, &wdm_device_list, device_list)
145 if (desc->intf->minor == minor)
147 spin_unlock(&wdm_device_list_lock);
152 /* --- callbacks --- */
153 static void wdm_out_callback(struct urb *urb)
155 struct wdm_device *desc;
157 spin_lock(&desc->iuspin);
158 desc->werr = urb->status;
159 spin_unlock(&desc->iuspin);
162 clear_bit(WDM_IN_USE, &desc->flags);
163 wake_up(&desc->wait);
166 static void wdm_in_callback(struct urb *urb)
168 struct wdm_device *desc = urb->context;
169 int status = urb->status;
171 spin_lock(&desc->iuspin);
172 clear_bit(WDM_RESPONDING, &desc->flags);
177 dev_dbg(&desc->intf->dev,
178 "nonzero urb status received: -ENOENT");
181 dev_dbg(&desc->intf->dev,
182 "nonzero urb status received: -ECONNRESET");
185 dev_dbg(&desc->intf->dev,
186 "nonzero urb status received: -ESHUTDOWN");
189 dev_err(&desc->intf->dev,
190 "nonzero urb status received: -EPIPE\n");
193 dev_err(&desc->intf->dev,
194 "Unexpected error %d\n", status);
200 desc->reslength = urb->actual_length;
201 memmove(desc->ubuf + desc->length, desc->inbuf, desc->reslength);
202 desc->length += desc->reslength;
204 wake_up(&desc->wait);
206 set_bit(WDM_READ, &desc->flags);
207 spin_unlock(&desc->iuspin);
210 static void wdm_int_callback(struct urb *urb)
213 int status = urb->status;
214 struct wdm_device *desc;
215 struct usb_cdc_notification *dr;
218 dr = (struct usb_cdc_notification *)desc->sbuf;
227 set_bit(WDM_INT_STALL, &desc->flags);
228 dev_err(&desc->intf->dev, "Stall on int endpoint\n");
229 goto sw; /* halt is cleared in work */
231 dev_err(&desc->intf->dev,
232 "nonzero urb status received: %d\n", status);
237 if (urb->actual_length < sizeof(struct usb_cdc_notification)) {
238 dev_err(&desc->intf->dev, "wdm_int_callback - %d bytes\n",
243 switch (dr->bNotificationType) {
244 case USB_CDC_NOTIFY_RESPONSE_AVAILABLE:
245 dev_dbg(&desc->intf->dev,
246 "NOTIFY_RESPONSE_AVAILABLE received: index %d len %d",
247 dr->wIndex, dr->wLength);
250 case USB_CDC_NOTIFY_NETWORK_CONNECTION:
252 dev_dbg(&desc->intf->dev,
253 "NOTIFY_NETWORK_CONNECTION %s network",
254 dr->wValue ? "connected to" : "disconnected from");
257 clear_bit(WDM_POLL_RUNNING, &desc->flags);
258 dev_err(&desc->intf->dev,
259 "unknown notification %d received: index %d len %d\n",
260 dr->bNotificationType, dr->wIndex, dr->wLength);
264 spin_lock(&desc->iuspin);
265 clear_bit(WDM_READ, &desc->flags);
266 set_bit(WDM_RESPONDING, &desc->flags);
267 if (!test_bit(WDM_DISCONNECTING, &desc->flags)
268 && !test_bit(WDM_SUSPENDING, &desc->flags)) {
269 rv = usb_submit_urb(desc->response, GFP_ATOMIC);
270 dev_dbg(&desc->intf->dev, "%s: usb_submit_urb %d",
273 spin_unlock(&desc->iuspin);
275 clear_bit(WDM_RESPONDING, &desc->flags);
280 rv = schedule_work(&desc->rxwork);
282 dev_err(&desc->intf->dev,
283 "Cannot schedule work\n");
287 rv = usb_submit_urb(urb, GFP_ATOMIC);
289 dev_err(&desc->intf->dev,
290 "%s - usb_submit_urb failed with result %d\n",
295 static void kill_urbs(struct wdm_device *desc)
297 /* the order here is essential */
298 usb_kill_urb(desc->command);
299 usb_kill_urb(desc->validity);
300 usb_kill_urb(desc->response);
303 static void free_urbs(struct wdm_device *desc)
305 usb_free_urb(desc->validity);
306 usb_free_urb(desc->response);
307 usb_free_urb(desc->command);
310 static void cleanup(struct wdm_device *desc)
321 static ssize_t wdm_write
322 (struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
325 int rv = -EMSGSIZE, r, we;
326 struct wdm_device *desc = file->private_data;
327 struct usb_ctrlrequest *req;
329 if (count > desc->wMaxCommand)
330 count = desc->wMaxCommand;
332 spin_lock_irq(&desc->iuspin);
335 spin_unlock_irq(&desc->iuspin);
339 buf = kmalloc(count, GFP_KERNEL);
345 r = copy_from_user(buf, buffer, count);
352 /* concurrent writes and disconnect */
353 r = mutex_lock_interruptible(&desc->wlock);
360 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
366 r = usb_autopm_get_interface(desc->intf);
369 rv = usb_translate_errors(r);
373 if (!(file->f_flags & O_NONBLOCK))
374 r = wait_event_interruptible(desc->wait, !test_bit(WDM_IN_USE,
377 if (test_bit(WDM_IN_USE, &desc->flags))
380 if (test_bit(WDM_RESETTING, &desc->flags))
390 usb_fill_control_urb(
392 interface_to_usbdev(desc->intf),
393 /* using common endpoint 0 */
394 usb_sndctrlpipe(interface_to_usbdev(desc->intf), 0),
395 (unsigned char *)req,
402 req->bRequestType = (USB_DIR_OUT | USB_TYPE_CLASS |
403 USB_RECIP_INTERFACE);
404 req->bRequest = USB_CDC_SEND_ENCAPSULATED_COMMAND;
406 req->wIndex = desc->inum;
407 req->wLength = cpu_to_le16(count);
408 set_bit(WDM_IN_USE, &desc->flags);
411 rv = usb_submit_urb(desc->command, GFP_KERNEL);
415 clear_bit(WDM_IN_USE, &desc->flags);
416 dev_err(&desc->intf->dev, "Tx URB error: %d\n", rv);
417 rv = usb_translate_errors(rv);
419 dev_dbg(&desc->intf->dev, "Tx URB has been submitted index=%d",
423 usb_autopm_put_interface(desc->intf);
425 mutex_unlock(&desc->wlock);
427 return rv < 0 ? rv : count;
430 static ssize_t wdm_read
431 (struct file *file, char __user *buffer, size_t count, loff_t *ppos)
435 struct wdm_device *desc = file->private_data;
438 rv = mutex_lock_interruptible(&desc->rlock); /*concurrent reads */
442 cntr = ACCESS_ONCE(desc->length);
446 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
451 if (file->f_flags & O_NONBLOCK) {
452 if (!test_bit(WDM_READ, &desc->flags)) {
453 rv = cntr ? cntr : -EAGAIN;
458 rv = wait_event_interruptible(desc->wait,
459 test_bit(WDM_READ, &desc->flags));
462 /* may have happened while we slept */
463 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
467 if (test_bit(WDM_RESETTING, &desc->flags)) {
471 usb_mark_last_busy(interface_to_usbdev(desc->intf));
477 spin_lock_irq(&desc->iuspin);
479 if (desc->rerr) { /* read completed, error happened */
481 spin_unlock_irq(&desc->iuspin);
486 * recheck whether we've lost the race
487 * against the completion handler
489 if (!test_bit(WDM_READ, &desc->flags)) { /* lost race */
490 spin_unlock_irq(&desc->iuspin);
493 if (!desc->reslength) { /* zero length read */
494 spin_unlock_irq(&desc->iuspin);
498 spin_unlock_irq(&desc->iuspin);
503 rv = copy_to_user(buffer, desc->ubuf, cntr);
509 spin_lock_irq(&desc->iuspin);
511 for (i = 0; i < desc->length - cntr; i++)
512 desc->ubuf[i] = desc->ubuf[i + cntr];
514 desc->length -= cntr;
515 /* in case we had outstanding data */
517 clear_bit(WDM_READ, &desc->flags);
519 spin_unlock_irq(&desc->iuspin);
524 mutex_unlock(&desc->rlock);
528 static int wdm_flush(struct file *file, fl_owner_t id)
530 struct wdm_device *desc = file->private_data;
532 wait_event(desc->wait, !test_bit(WDM_IN_USE, &desc->flags));
534 /* cannot dereference desc->intf if WDM_DISCONNECTING */
535 if (desc->werr < 0 && !test_bit(WDM_DISCONNECTING, &desc->flags))
536 dev_err(&desc->intf->dev, "Error in flush path: %d\n",
539 return usb_translate_errors(desc->werr);
542 static unsigned int wdm_poll(struct file *file, struct poll_table_struct *wait)
544 struct wdm_device *desc = file->private_data;
546 unsigned int mask = 0;
548 spin_lock_irqsave(&desc->iuspin, flags);
549 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
550 mask = POLLHUP | POLLERR;
551 spin_unlock_irqrestore(&desc->iuspin, flags);
554 if (test_bit(WDM_READ, &desc->flags))
555 mask = POLLIN | POLLRDNORM;
556 if (desc->rerr || desc->werr)
558 if (!test_bit(WDM_IN_USE, &desc->flags))
559 mask |= POLLOUT | POLLWRNORM;
560 spin_unlock_irqrestore(&desc->iuspin, flags);
562 poll_wait(file, &desc->wait, wait);
568 static int wdm_open(struct inode *inode, struct file *file)
570 int minor = iminor(inode);
572 struct usb_interface *intf;
573 struct wdm_device *desc;
575 mutex_lock(&wdm_mutex);
576 desc = wdm_find_device_by_minor(minor);
581 if (test_bit(WDM_DISCONNECTING, &desc->flags))
583 file->private_data = desc;
585 rv = usb_autopm_get_interface(desc->intf);
587 dev_err(&desc->intf->dev, "Error autopm - %d\n", rv);
591 /* using write lock to protect desc->count */
592 mutex_lock(&desc->wlock);
593 if (!desc->count++) {
596 rv = usb_submit_urb(desc->validity, GFP_KERNEL);
599 dev_err(&desc->intf->dev,
600 "Error submitting int urb - %d\n", rv);
601 rv = usb_translate_errors(rv);
606 mutex_unlock(&desc->wlock);
607 if (desc->count == 1)
608 desc->manage_power(intf, 1);
609 usb_autopm_put_interface(desc->intf);
611 mutex_unlock(&wdm_mutex);
615 static int wdm_release(struct inode *inode, struct file *file)
617 struct wdm_device *desc = file->private_data;
619 mutex_lock(&wdm_mutex);
621 /* using write lock to protect desc->count */
622 mutex_lock(&desc->wlock);
624 mutex_unlock(&desc->wlock);
627 if (!test_bit(WDM_DISCONNECTING, &desc->flags)) {
628 dev_dbg(&desc->intf->dev, "wdm_release: cleanup");
630 desc->manage_power(desc->intf, 0);
632 /* must avoid dev_printk here as desc->intf is invalid */
633 pr_debug(KBUILD_MODNAME " %s: device gone - cleaning up\n", __func__);
637 mutex_unlock(&wdm_mutex);
641 static const struct file_operations wdm_fops = {
642 .owner = THIS_MODULE,
647 .release = wdm_release,
649 .llseek = noop_llseek,
652 static struct usb_class_driver wdm_class = {
655 .minor_base = WDM_MINOR_BASE,
658 /* --- error handling --- */
659 static void wdm_rxwork(struct work_struct *work)
661 struct wdm_device *desc = container_of(work, struct wdm_device, rxwork);
665 spin_lock_irqsave(&desc->iuspin, flags);
666 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
667 spin_unlock_irqrestore(&desc->iuspin, flags);
669 spin_unlock_irqrestore(&desc->iuspin, flags);
670 rv = usb_submit_urb(desc->response, GFP_KERNEL);
671 if (rv < 0 && rv != -EPERM) {
672 spin_lock_irqsave(&desc->iuspin, flags);
673 if (!test_bit(WDM_DISCONNECTING, &desc->flags))
674 schedule_work(&desc->rxwork);
675 spin_unlock_irqrestore(&desc->iuspin, flags);
680 /* --- hotplug --- */
682 static int wdm_create(struct usb_interface *intf, struct usb_endpoint_descriptor *ep,
683 u16 bufsize, int (*manage_power)(struct usb_interface *, int))
686 struct wdm_device *desc;
688 desc = kzalloc(sizeof(struct wdm_device), GFP_KERNEL);
691 INIT_LIST_HEAD(&desc->device_list);
692 mutex_init(&desc->rlock);
693 mutex_init(&desc->wlock);
694 spin_lock_init(&desc->iuspin);
695 init_waitqueue_head(&desc->wait);
696 desc->wMaxCommand = bufsize;
697 /* this will be expanded and needed in hardware endianness */
698 desc->inum = cpu_to_le16((u16)intf->cur_altsetting->desc.bInterfaceNumber);
700 INIT_WORK(&desc->rxwork, wdm_rxwork);
703 if (!usb_endpoint_is_int_in(ep))
706 desc->wMaxPacketSize = usb_endpoint_maxp(ep);
708 desc->orq = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
711 desc->irq = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
715 desc->validity = usb_alloc_urb(0, GFP_KERNEL);
719 desc->response = usb_alloc_urb(0, GFP_KERNEL);
723 desc->command = usb_alloc_urb(0, GFP_KERNEL);
727 desc->ubuf = kmalloc(desc->wMaxCommand, GFP_KERNEL);
731 desc->sbuf = kmalloc(desc->wMaxPacketSize, GFP_KERNEL);
735 desc->inbuf = kmalloc(desc->wMaxCommand, GFP_KERNEL);
741 interface_to_usbdev(intf),
742 usb_rcvintpipe(interface_to_usbdev(intf), ep->bEndpointAddress),
744 desc->wMaxPacketSize,
750 desc->irq->bRequestType = (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE);
751 desc->irq->bRequest = USB_CDC_GET_ENCAPSULATED_RESPONSE;
752 desc->irq->wValue = 0;
753 desc->irq->wIndex = desc->inum;
754 desc->irq->wLength = cpu_to_le16(desc->wMaxCommand);
756 usb_fill_control_urb(
758 interface_to_usbdev(intf),
759 /* using common endpoint 0 */
760 usb_rcvctrlpipe(interface_to_usbdev(desc->intf), 0),
761 (unsigned char *)desc->irq,
768 desc->manage_power = manage_power;
770 spin_lock(&wdm_device_list_lock);
771 list_add(&desc->device_list, &wdm_device_list);
772 spin_unlock(&wdm_device_list_lock);
774 rv = usb_register_dev(intf, &wdm_class);
778 dev_info(&intf->dev, "%s: USB WDM device\n", dev_name(intf->usb_dev));
782 spin_lock(&wdm_device_list_lock);
783 list_del(&desc->device_list);
784 spin_unlock(&wdm_device_list_lock);
789 static int wdm_manage_power(struct usb_interface *intf, int on)
791 /* need autopm_get/put here to ensure the usbcore sees the new value */
792 int rv = usb_autopm_get_interface(intf);
796 intf->needs_remote_wakeup = on;
797 usb_autopm_put_interface(intf);
802 static int wdm_probe(struct usb_interface *intf, const struct usb_device_id *id)
805 struct usb_host_interface *iface;
806 struct usb_endpoint_descriptor *ep;
807 struct usb_cdc_dmm_desc *dmhd;
808 u8 *buffer = intf->altsetting->extra;
809 int buflen = intf->altsetting->extralen;
810 u16 maxcom = WDM_DEFAULT_BUFSIZE;
815 if (buffer[1] != USB_DT_CS_INTERFACE) {
816 dev_err(&intf->dev, "skipping garbage\n");
821 case USB_CDC_HEADER_TYPE:
823 case USB_CDC_DMM_TYPE:
824 dmhd = (struct usb_cdc_dmm_desc *)buffer;
825 maxcom = le16_to_cpu(dmhd->wMaxCommand);
827 "Finding maximum buffer length: %d", maxcom);
831 "Ignoring extra header, type %d, length %d\n",
832 buffer[2], buffer[0]);
840 iface = intf->cur_altsetting;
841 if (iface->desc.bNumEndpoints != 1)
843 ep = &iface->endpoint[0].desc;
845 rv = wdm_create(intf, ep, maxcom, &wdm_manage_power);
852 * usb_cdc_wdm_register - register a WDM subdriver
853 * @intf: usb interface the subdriver will associate with
854 * @ep: interrupt endpoint to monitor for notifications
855 * @bufsize: maximum message size to support for read/write
857 * Create WDM usb class character device and associate it with intf
858 * without binding, allowing another driver to manage the interface.
860 * The subdriver will manage the given interrupt endpoint exclusively
861 * and will issue control requests referring to the given intf. It
862 * will otherwise avoid interferring, and in particular not do
863 * usb_set_intfdata/usb_get_intfdata on intf.
865 * The return value is a pointer to the subdriver's struct usb_driver.
866 * The registering driver is responsible for calling this subdriver's
867 * disconnect, suspend, resume, pre_reset and post_reset methods from
870 struct usb_driver *usb_cdc_wdm_register(struct usb_interface *intf,
871 struct usb_endpoint_descriptor *ep,
873 int (*manage_power)(struct usb_interface *, int))
877 rv = wdm_create(intf, ep, bufsize, manage_power);
885 EXPORT_SYMBOL(usb_cdc_wdm_register);
887 static void wdm_disconnect(struct usb_interface *intf)
889 struct wdm_device *desc;
892 usb_deregister_dev(intf, &wdm_class);
893 desc = wdm_find_device(intf);
894 mutex_lock(&wdm_mutex);
896 /* the spinlock makes sure no new urbs are generated in the callbacks */
897 spin_lock_irqsave(&desc->iuspin, flags);
898 set_bit(WDM_DISCONNECTING, &desc->flags);
899 set_bit(WDM_READ, &desc->flags);
900 /* to terminate pending flushes */
901 clear_bit(WDM_IN_USE, &desc->flags);
902 spin_unlock_irqrestore(&desc->iuspin, flags);
903 wake_up_all(&desc->wait);
904 mutex_lock(&desc->rlock);
905 mutex_lock(&desc->wlock);
907 cancel_work_sync(&desc->rxwork);
908 mutex_unlock(&desc->wlock);
909 mutex_unlock(&desc->rlock);
911 /* the desc->intf pointer used as list key is now invalid */
912 spin_lock(&wdm_device_list_lock);
913 list_del(&desc->device_list);
914 spin_unlock(&wdm_device_list_lock);
919 dev_dbg(&intf->dev, "%s: %d open files - postponing cleanup\n", __func__, desc->count);
920 mutex_unlock(&wdm_mutex);
924 static int wdm_suspend(struct usb_interface *intf, pm_message_t message)
926 struct wdm_device *desc = wdm_find_device(intf);
929 dev_dbg(&desc->intf->dev, "wdm%d_suspend\n", intf->minor);
931 /* if this is an autosuspend the caller does the locking */
932 if (!PMSG_IS_AUTO(message)) {
933 mutex_lock(&desc->rlock);
934 mutex_lock(&desc->wlock);
936 spin_lock_irq(&desc->iuspin);
938 if (PMSG_IS_AUTO(message) &&
939 (test_bit(WDM_IN_USE, &desc->flags)
940 || test_bit(WDM_RESPONDING, &desc->flags))) {
941 spin_unlock_irq(&desc->iuspin);
945 set_bit(WDM_SUSPENDING, &desc->flags);
946 spin_unlock_irq(&desc->iuspin);
947 /* callback submits work - order is essential */
949 cancel_work_sync(&desc->rxwork);
951 if (!PMSG_IS_AUTO(message)) {
952 mutex_unlock(&desc->wlock);
953 mutex_unlock(&desc->rlock);
960 static int recover_from_urb_loss(struct wdm_device *desc)
965 rv = usb_submit_urb(desc->validity, GFP_NOIO);
967 dev_err(&desc->intf->dev,
968 "Error resume submitting int urb - %d\n", rv);
974 static int wdm_resume(struct usb_interface *intf)
976 struct wdm_device *desc = wdm_find_device(intf);
979 dev_dbg(&desc->intf->dev, "wdm%d_resume\n", intf->minor);
981 clear_bit(WDM_SUSPENDING, &desc->flags);
982 rv = recover_from_urb_loss(desc);
988 static int wdm_pre_reset(struct usb_interface *intf)
990 struct wdm_device *desc = wdm_find_device(intf);
993 * we notify everybody using poll of
994 * an exceptional situation
995 * must be done before recovery lest a spontaneous
996 * message from the device is lost
998 spin_lock_irq(&desc->iuspin);
999 set_bit(WDM_RESETTING, &desc->flags); /* inform read/write */
1000 set_bit(WDM_READ, &desc->flags); /* unblock read */
1001 clear_bit(WDM_IN_USE, &desc->flags); /* unblock write */
1002 desc->rerr = -EINTR;
1003 spin_unlock_irq(&desc->iuspin);
1004 wake_up_all(&desc->wait);
1005 mutex_lock(&desc->rlock);
1006 mutex_lock(&desc->wlock);
1008 cancel_work_sync(&desc->rxwork);
1012 static int wdm_post_reset(struct usb_interface *intf)
1014 struct wdm_device *desc = wdm_find_device(intf);
1017 clear_bit(WDM_RESETTING, &desc->flags);
1018 rv = recover_from_urb_loss(desc);
1019 mutex_unlock(&desc->wlock);
1020 mutex_unlock(&desc->rlock);
1024 static struct usb_driver wdm_driver = {
1027 .disconnect = wdm_disconnect,
1029 .suspend = wdm_suspend,
1030 .resume = wdm_resume,
1031 .reset_resume = wdm_resume,
1033 .pre_reset = wdm_pre_reset,
1034 .post_reset = wdm_post_reset,
1035 .id_table = wdm_ids,
1036 .supports_autosuspend = 1,
1037 .disable_hub_initiated_lpm = 1,
1040 module_usb_driver(wdm_driver);
1042 MODULE_AUTHOR(DRIVER_AUTHOR);
1043 MODULE_DESCRIPTION(DRIVER_DESC);
1044 MODULE_LICENSE("GPL");