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>
30 #define DRIVER_VERSION "v0.03"
31 #define DRIVER_AUTHOR "Oliver Neukum"
32 #define DRIVER_DESC "USB Abstract Control Model driver for USB WCM Device Management"
34 #define HUAWEI_VENDOR_ID 0x12D1
36 static const struct usb_device_id wdm_ids[] = {
38 .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS |
39 USB_DEVICE_ID_MATCH_INT_SUBCLASS,
40 .bInterfaceClass = USB_CLASS_COMM,
41 .bInterfaceSubClass = USB_CDC_SUBCLASS_DMM
45 * Huawei E392, E398 and possibly other Qualcomm based modems
46 * embed the Qualcomm QMI protocol inside CDC on CDC ECM like
47 * control interfaces. Userspace access to this is required
48 * to configure the accompanying data interface
50 .match_flags = USB_DEVICE_ID_MATCH_VENDOR |
51 USB_DEVICE_ID_MATCH_INT_INFO,
52 .idVendor = HUAWEI_VENDOR_ID,
53 .bInterfaceClass = USB_CLASS_VENDOR_SPEC,
54 .bInterfaceSubClass = 1,
55 .bInterfaceProtocol = 9, /* NOTE: CDC ECM control interface! */
60 MODULE_DEVICE_TABLE (usb, wdm_ids);
62 #define WDM_MINOR_BASE 176
66 #define WDM_DISCONNECTING 2
69 #define WDM_INT_STALL 5
70 #define WDM_POLL_RUNNING 6
71 #define WDM_RESPONDING 7
72 #define WDM_SUSPENDING 8
73 #define WDM_RESETTING 9
77 /* CDC-WMC r1.1 requires wMaxCommand to be "at least 256 decimal (0x100)" */
78 #define WDM_DEFAULT_BUFSIZE 256
80 static DEFINE_MUTEX(wdm_mutex);
82 /* --- method tables --- */
85 u8 *inbuf; /* buffer for response */
86 u8 *outbuf; /* buffer for command */
87 u8 *sbuf; /* buffer for status */
88 u8 *ubuf; /* buffer for copy to user space */
93 struct usb_interface *intf;
94 struct usb_ctrlrequest *orq;
95 struct usb_ctrlrequest *irq;
111 wait_queue_head_t wait;
112 struct work_struct rxwork;
117 static struct usb_driver wdm_driver;
119 /* --- callbacks --- */
120 static void wdm_out_callback(struct urb *urb)
122 struct wdm_device *desc;
124 spin_lock(&desc->iuspin);
125 desc->werr = urb->status;
126 spin_unlock(&desc->iuspin);
127 clear_bit(WDM_IN_USE, &desc->flags);
129 wake_up(&desc->wait);
132 static void wdm_in_callback(struct urb *urb)
134 struct wdm_device *desc = urb->context;
135 int status = urb->status;
137 spin_lock(&desc->iuspin);
138 clear_bit(WDM_RESPONDING, &desc->flags);
143 dev_dbg(&desc->intf->dev,
144 "nonzero urb status received: -ENOENT");
147 dev_dbg(&desc->intf->dev,
148 "nonzero urb status received: -ECONNRESET");
151 dev_dbg(&desc->intf->dev,
152 "nonzero urb status received: -ESHUTDOWN");
155 dev_err(&desc->intf->dev,
156 "nonzero urb status received: -EPIPE\n");
159 dev_err(&desc->intf->dev,
160 "Unexpected error %d\n", status);
166 desc->reslength = urb->actual_length;
167 memmove(desc->ubuf + desc->length, desc->inbuf, desc->reslength);
168 desc->length += desc->reslength;
170 wake_up(&desc->wait);
172 set_bit(WDM_READ, &desc->flags);
173 spin_unlock(&desc->iuspin);
176 static void wdm_int_callback(struct urb *urb)
179 int status = urb->status;
180 struct wdm_device *desc;
181 struct usb_cdc_notification *dr;
184 dr = (struct usb_cdc_notification *)desc->sbuf;
193 set_bit(WDM_INT_STALL, &desc->flags);
194 dev_err(&desc->intf->dev, "Stall on int endpoint\n");
195 goto sw; /* halt is cleared in work */
197 dev_err(&desc->intf->dev,
198 "nonzero urb status received: %d\n", status);
203 if (urb->actual_length < sizeof(struct usb_cdc_notification)) {
204 dev_err(&desc->intf->dev, "wdm_int_callback - %d bytes\n",
209 switch (dr->bNotificationType) {
210 case USB_CDC_NOTIFY_RESPONSE_AVAILABLE:
211 dev_dbg(&desc->intf->dev,
212 "NOTIFY_RESPONSE_AVAILABLE received: index %d len %d",
213 dr->wIndex, dr->wLength);
216 case USB_CDC_NOTIFY_NETWORK_CONNECTION:
218 dev_dbg(&desc->intf->dev,
219 "NOTIFY_NETWORK_CONNECTION %s network",
220 dr->wValue ? "connected to" : "disconnected from");
223 clear_bit(WDM_POLL_RUNNING, &desc->flags);
224 dev_err(&desc->intf->dev,
225 "unknown notification %d received: index %d len %d\n",
226 dr->bNotificationType, dr->wIndex, dr->wLength);
230 spin_lock(&desc->iuspin);
231 clear_bit(WDM_READ, &desc->flags);
232 set_bit(WDM_RESPONDING, &desc->flags);
233 if (!test_bit(WDM_DISCONNECTING, &desc->flags)
234 && !test_bit(WDM_SUSPENDING, &desc->flags)) {
235 rv = usb_submit_urb(desc->response, GFP_ATOMIC);
236 dev_dbg(&desc->intf->dev, "%s: usb_submit_urb %d",
239 spin_unlock(&desc->iuspin);
241 clear_bit(WDM_RESPONDING, &desc->flags);
246 rv = schedule_work(&desc->rxwork);
248 dev_err(&desc->intf->dev,
249 "Cannot schedule work\n");
253 rv = usb_submit_urb(urb, GFP_ATOMIC);
255 dev_err(&desc->intf->dev,
256 "%s - usb_submit_urb failed with result %d\n",
261 static void kill_urbs(struct wdm_device *desc)
263 /* the order here is essential */
264 usb_kill_urb(desc->command);
265 usb_kill_urb(desc->validity);
266 usb_kill_urb(desc->response);
269 static void free_urbs(struct wdm_device *desc)
271 usb_free_urb(desc->validity);
272 usb_free_urb(desc->response);
273 usb_free_urb(desc->command);
276 static void cleanup(struct wdm_device *desc)
287 static ssize_t wdm_write
288 (struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
291 int rv = -EMSGSIZE, r, we;
292 struct wdm_device *desc = file->private_data;
293 struct usb_ctrlrequest *req;
295 if (count > desc->wMaxCommand)
296 count = desc->wMaxCommand;
298 spin_lock_irq(&desc->iuspin);
301 spin_unlock_irq(&desc->iuspin);
305 desc->outbuf = buf = kmalloc(count, GFP_KERNEL);
311 r = copy_from_user(buf, buffer, count);
318 /* concurrent writes and disconnect */
319 r = mutex_lock_interruptible(&desc->wlock);
326 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
332 r = usb_autopm_get_interface(desc->intf);
338 if (!(file->f_flags & O_NONBLOCK))
339 r = wait_event_interruptible(desc->wait, !test_bit(WDM_IN_USE,
342 if (test_bit(WDM_IN_USE, &desc->flags))
345 if (test_bit(WDM_RESETTING, &desc->flags))
354 usb_fill_control_urb(
356 interface_to_usbdev(desc->intf),
357 /* using common endpoint 0 */
358 usb_sndctrlpipe(interface_to_usbdev(desc->intf), 0),
359 (unsigned char *)req,
366 req->bRequestType = (USB_DIR_OUT | USB_TYPE_CLASS |
367 USB_RECIP_INTERFACE);
368 req->bRequest = USB_CDC_SEND_ENCAPSULATED_COMMAND;
370 req->wIndex = desc->inum;
371 req->wLength = cpu_to_le16(count);
372 set_bit(WDM_IN_USE, &desc->flags);
374 rv = usb_submit_urb(desc->command, GFP_KERNEL);
377 clear_bit(WDM_IN_USE, &desc->flags);
378 dev_err(&desc->intf->dev, "Tx URB error: %d\n", rv);
380 dev_dbg(&desc->intf->dev, "Tx URB has been submitted index=%d",
384 usb_autopm_put_interface(desc->intf);
386 mutex_unlock(&desc->wlock);
388 return rv < 0 ? rv : count;
391 static ssize_t wdm_read
392 (struct file *file, char __user *buffer, size_t count, loff_t *ppos)
396 struct wdm_device *desc = file->private_data;
399 rv = mutex_lock_interruptible(&desc->rlock); /*concurrent reads */
403 cntr = ACCESS_ONCE(desc->length);
407 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
412 if (file->f_flags & O_NONBLOCK) {
413 if (!test_bit(WDM_READ, &desc->flags)) {
414 rv = cntr ? cntr : -EAGAIN;
419 rv = wait_event_interruptible(desc->wait,
420 test_bit(WDM_READ, &desc->flags));
423 /* may have happened while we slept */
424 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
428 if (test_bit(WDM_RESETTING, &desc->flags)) {
432 usb_mark_last_busy(interface_to_usbdev(desc->intf));
438 spin_lock_irq(&desc->iuspin);
440 if (desc->rerr) { /* read completed, error happened */
442 spin_unlock_irq(&desc->iuspin);
447 * recheck whether we've lost the race
448 * against the completion handler
450 if (!test_bit(WDM_READ, &desc->flags)) { /* lost race */
451 spin_unlock_irq(&desc->iuspin);
454 if (!desc->reslength) { /* zero length read */
455 spin_unlock_irq(&desc->iuspin);
459 spin_unlock_irq(&desc->iuspin);
464 rv = copy_to_user(buffer, desc->ubuf, cntr);
470 spin_lock_irq(&desc->iuspin);
472 for (i = 0; i < desc->length - cntr; i++)
473 desc->ubuf[i] = desc->ubuf[i + cntr];
475 desc->length -= cntr;
476 /* in case we had outstanding data */
478 clear_bit(WDM_READ, &desc->flags);
480 spin_unlock_irq(&desc->iuspin);
485 mutex_unlock(&desc->rlock);
489 static int wdm_flush(struct file *file, fl_owner_t id)
491 struct wdm_device *desc = file->private_data;
493 wait_event(desc->wait, !test_bit(WDM_IN_USE, &desc->flags));
495 dev_err(&desc->intf->dev, "Error in flush path: %d\n",
501 static unsigned int wdm_poll(struct file *file, struct poll_table_struct *wait)
503 struct wdm_device *desc = file->private_data;
505 unsigned int mask = 0;
507 spin_lock_irqsave(&desc->iuspin, flags);
508 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
510 spin_unlock_irqrestore(&desc->iuspin, flags);
513 if (test_bit(WDM_READ, &desc->flags))
514 mask = POLLIN | POLLRDNORM;
515 if (desc->rerr || desc->werr)
517 if (!test_bit(WDM_IN_USE, &desc->flags))
518 mask |= POLLOUT | POLLWRNORM;
519 spin_unlock_irqrestore(&desc->iuspin, flags);
521 poll_wait(file, &desc->wait, wait);
527 static int wdm_open(struct inode *inode, struct file *file)
529 int minor = iminor(inode);
531 struct usb_interface *intf;
532 struct wdm_device *desc;
534 mutex_lock(&wdm_mutex);
535 intf = usb_find_interface(&wdm_driver, minor);
539 desc = usb_get_intfdata(intf);
540 if (test_bit(WDM_DISCONNECTING, &desc->flags))
542 file->private_data = desc;
544 rv = usb_autopm_get_interface(desc->intf);
546 dev_err(&desc->intf->dev, "Error autopm - %d\n", rv);
549 intf->needs_remote_wakeup = 1;
551 /* using write lock to protect desc->count */
552 mutex_lock(&desc->wlock);
553 if (!desc->count++) {
556 rv = usb_submit_urb(desc->validity, GFP_KERNEL);
559 dev_err(&desc->intf->dev,
560 "Error submitting int urb - %d\n", rv);
565 mutex_unlock(&desc->wlock);
566 usb_autopm_put_interface(desc->intf);
568 mutex_unlock(&wdm_mutex);
572 static int wdm_release(struct inode *inode, struct file *file)
574 struct wdm_device *desc = file->private_data;
576 mutex_lock(&wdm_mutex);
578 /* using write lock to protect desc->count */
579 mutex_lock(&desc->wlock);
581 mutex_unlock(&desc->wlock);
584 dev_dbg(&desc->intf->dev, "wdm_release: cleanup");
586 if (!test_bit(WDM_DISCONNECTING, &desc->flags))
587 desc->intf->needs_remote_wakeup = 0;
589 mutex_unlock(&wdm_mutex);
593 static const struct file_operations wdm_fops = {
594 .owner = THIS_MODULE,
599 .release = wdm_release,
601 .llseek = noop_llseek,
604 static struct usb_class_driver wdm_class = {
607 .minor_base = WDM_MINOR_BASE,
610 /* --- error handling --- */
611 static void wdm_rxwork(struct work_struct *work)
613 struct wdm_device *desc = container_of(work, struct wdm_device, rxwork);
617 spin_lock_irqsave(&desc->iuspin, flags);
618 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
619 spin_unlock_irqrestore(&desc->iuspin, flags);
621 spin_unlock_irqrestore(&desc->iuspin, flags);
622 rv = usb_submit_urb(desc->response, GFP_KERNEL);
623 if (rv < 0 && rv != -EPERM) {
624 spin_lock_irqsave(&desc->iuspin, flags);
625 if (!test_bit(WDM_DISCONNECTING, &desc->flags))
626 schedule_work(&desc->rxwork);
627 spin_unlock_irqrestore(&desc->iuspin, flags);
632 /* --- hotplug --- */
634 static int wdm_probe(struct usb_interface *intf, const struct usb_device_id *id)
637 struct wdm_device *desc;
638 struct usb_host_interface *iface;
639 struct usb_endpoint_descriptor *ep;
640 struct usb_cdc_dmm_desc *dmhd;
641 u8 *buffer = intf->altsetting->extra;
642 int buflen = intf->altsetting->extralen;
643 u16 maxcom = WDM_DEFAULT_BUFSIZE;
649 if (buffer [1] != USB_DT_CS_INTERFACE) {
650 dev_err(&intf->dev, "skipping garbage\n");
654 switch (buffer [2]) {
655 case USB_CDC_HEADER_TYPE:
657 case USB_CDC_DMM_TYPE:
658 dmhd = (struct usb_cdc_dmm_desc *)buffer;
659 maxcom = le16_to_cpu(dmhd->wMaxCommand);
661 "Finding maximum buffer length: %d", maxcom);
665 "Ignoring extra header, type %d, length %d\n",
666 buffer[2], buffer[0]);
675 desc = kzalloc(sizeof(struct wdm_device), GFP_KERNEL);
678 mutex_init(&desc->rlock);
679 mutex_init(&desc->wlock);
680 spin_lock_init(&desc->iuspin);
681 init_waitqueue_head(&desc->wait);
682 desc->wMaxCommand = maxcom;
683 /* this will be expanded and needed in hardware endianness */
684 desc->inum = cpu_to_le16((u16)intf->cur_altsetting->desc.bInterfaceNumber);
686 INIT_WORK(&desc->rxwork, wdm_rxwork);
689 iface = intf->cur_altsetting;
690 if (iface->desc.bNumEndpoints != 1)
692 ep = &iface->endpoint[0].desc;
693 if (!ep || !usb_endpoint_is_int_in(ep))
696 desc->wMaxPacketSize = usb_endpoint_maxp(ep);
698 desc->orq = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
701 desc->irq = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
705 desc->validity = usb_alloc_urb(0, GFP_KERNEL);
709 desc->response = usb_alloc_urb(0, GFP_KERNEL);
713 desc->command = usb_alloc_urb(0, GFP_KERNEL);
717 desc->ubuf = kmalloc(desc->wMaxCommand, GFP_KERNEL);
721 desc->sbuf = kmalloc(desc->wMaxPacketSize, GFP_KERNEL);
725 desc->inbuf = kmalloc(desc->wMaxCommand, GFP_KERNEL);
731 interface_to_usbdev(intf),
732 usb_rcvintpipe(interface_to_usbdev(intf), ep->bEndpointAddress),
734 desc->wMaxPacketSize,
740 desc->irq->bRequestType = (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE);
741 desc->irq->bRequest = USB_CDC_GET_ENCAPSULATED_RESPONSE;
742 desc->irq->wValue = 0;
743 desc->irq->wIndex = desc->inum;
744 desc->irq->wLength = cpu_to_le16(desc->wMaxCommand);
746 usb_fill_control_urb(
748 interface_to_usbdev(intf),
749 /* using common endpoint 0 */
750 usb_rcvctrlpipe(interface_to_usbdev(desc->intf), 0),
751 (unsigned char *)desc->irq,
758 usb_set_intfdata(intf, desc);
759 rv = usb_register_dev(intf, &wdm_class);
763 dev_info(&intf->dev, "%s: USB WDM device\n", dev_name(intf->usb_dev));
767 usb_set_intfdata(intf, NULL);
779 static void wdm_disconnect(struct usb_interface *intf)
781 struct wdm_device *desc;
784 usb_deregister_dev(intf, &wdm_class);
785 mutex_lock(&wdm_mutex);
786 desc = usb_get_intfdata(intf);
788 /* the spinlock makes sure no new urbs are generated in the callbacks */
789 spin_lock_irqsave(&desc->iuspin, flags);
790 set_bit(WDM_DISCONNECTING, &desc->flags);
791 set_bit(WDM_READ, &desc->flags);
792 /* to terminate pending flushes */
793 clear_bit(WDM_IN_USE, &desc->flags);
794 spin_unlock_irqrestore(&desc->iuspin, flags);
795 wake_up_all(&desc->wait);
796 mutex_lock(&desc->rlock);
797 mutex_lock(&desc->wlock);
799 cancel_work_sync(&desc->rxwork);
800 mutex_unlock(&desc->wlock);
801 mutex_unlock(&desc->rlock);
804 mutex_unlock(&wdm_mutex);
808 static int wdm_suspend(struct usb_interface *intf, pm_message_t message)
810 struct wdm_device *desc = usb_get_intfdata(intf);
813 dev_dbg(&desc->intf->dev, "wdm%d_suspend\n", intf->minor);
815 /* if this is an autosuspend the caller does the locking */
816 if (!PMSG_IS_AUTO(message)) {
817 mutex_lock(&desc->rlock);
818 mutex_lock(&desc->wlock);
820 spin_lock_irq(&desc->iuspin);
822 if (PMSG_IS_AUTO(message) &&
823 (test_bit(WDM_IN_USE, &desc->flags)
824 || test_bit(WDM_RESPONDING, &desc->flags))) {
825 spin_unlock_irq(&desc->iuspin);
829 set_bit(WDM_SUSPENDING, &desc->flags);
830 spin_unlock_irq(&desc->iuspin);
831 /* callback submits work - order is essential */
833 cancel_work_sync(&desc->rxwork);
835 if (!PMSG_IS_AUTO(message)) {
836 mutex_unlock(&desc->wlock);
837 mutex_unlock(&desc->rlock);
844 static int recover_from_urb_loss(struct wdm_device *desc)
849 rv = usb_submit_urb(desc->validity, GFP_NOIO);
851 dev_err(&desc->intf->dev,
852 "Error resume submitting int urb - %d\n", rv);
858 static int wdm_resume(struct usb_interface *intf)
860 struct wdm_device *desc = usb_get_intfdata(intf);
863 dev_dbg(&desc->intf->dev, "wdm%d_resume\n", intf->minor);
865 clear_bit(WDM_SUSPENDING, &desc->flags);
866 rv = recover_from_urb_loss(desc);
872 static int wdm_pre_reset(struct usb_interface *intf)
874 struct wdm_device *desc = usb_get_intfdata(intf);
877 * we notify everybody using poll of
878 * an exceptional situation
879 * must be done before recovery lest a spontaneous
880 * message from the device is lost
882 spin_lock_irq(&desc->iuspin);
883 set_bit(WDM_RESETTING, &desc->flags); /* inform read/write */
884 set_bit(WDM_READ, &desc->flags); /* unblock read */
885 clear_bit(WDM_IN_USE, &desc->flags); /* unblock write */
887 spin_unlock_irq(&desc->iuspin);
888 wake_up_all(&desc->wait);
889 mutex_lock(&desc->rlock);
890 mutex_lock(&desc->wlock);
892 cancel_work_sync(&desc->rxwork);
896 static int wdm_post_reset(struct usb_interface *intf)
898 struct wdm_device *desc = usb_get_intfdata(intf);
901 clear_bit(WDM_RESETTING, &desc->flags);
902 rv = recover_from_urb_loss(desc);
903 mutex_unlock(&desc->wlock);
904 mutex_unlock(&desc->rlock);
908 static struct usb_driver wdm_driver = {
911 .disconnect = wdm_disconnect,
913 .suspend = wdm_suspend,
914 .resume = wdm_resume,
915 .reset_resume = wdm_resume,
917 .pre_reset = wdm_pre_reset,
918 .post_reset = wdm_post_reset,
920 .supports_autosuspend = 1,
923 module_usb_driver(wdm_driver);
925 MODULE_AUTHOR(DRIVER_AUTHOR);
926 MODULE_DESCRIPTION(DRIVER_DESC);
927 MODULE_LICENSE("GPL");