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 static const struct usb_device_id wdm_ids[] = {
36 .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS |
37 USB_DEVICE_ID_MATCH_INT_SUBCLASS,
38 .bInterfaceClass = USB_CLASS_COMM,
39 .bInterfaceSubClass = USB_CDC_SUBCLASS_DMM
44 MODULE_DEVICE_TABLE (usb, wdm_ids);
46 #define WDM_MINOR_BASE 176
50 #define WDM_DISCONNECTING 2
53 #define WDM_INT_STALL 5
54 #define WDM_POLL_RUNNING 6
55 #define WDM_RESPONDING 7
61 static DEFINE_MUTEX(wdm_mutex);
63 /* --- method tables --- */
66 u8 *inbuf; /* buffer for response */
67 u8 *outbuf; /* buffer for command */
68 u8 *sbuf; /* buffer for status */
69 u8 *ubuf; /* buffer for copy to user space */
74 struct usb_interface *intf;
75 struct usb_ctrlrequest *orq;
76 struct usb_ctrlrequest *irq;
92 wait_queue_head_t wait;
93 struct work_struct rxwork;
98 static struct usb_driver wdm_driver;
100 /* --- callbacks --- */
101 static void wdm_out_callback(struct urb *urb)
103 struct wdm_device *desc;
105 spin_lock(&desc->iuspin);
106 desc->werr = urb->status;
107 spin_unlock(&desc->iuspin);
108 clear_bit(WDM_IN_USE, &desc->flags);
110 wake_up(&desc->wait);
113 static void wdm_in_callback(struct urb *urb)
115 struct wdm_device *desc = urb->context;
116 int status = urb->status;
118 spin_lock(&desc->iuspin);
119 clear_bit(WDM_RESPONDING, &desc->flags);
124 dev_dbg(&desc->intf->dev,
125 "nonzero urb status received: -ENOENT");
128 dev_dbg(&desc->intf->dev,
129 "nonzero urb status received: -ECONNRESET");
132 dev_dbg(&desc->intf->dev,
133 "nonzero urb status received: -ESHUTDOWN");
136 dev_err(&desc->intf->dev,
137 "nonzero urb status received: -EPIPE\n");
140 dev_err(&desc->intf->dev,
141 "Unexpected error %d\n", status);
147 desc->reslength = urb->actual_length;
148 memmove(desc->ubuf + desc->length, desc->inbuf, desc->reslength);
149 desc->length += desc->reslength;
151 wake_up(&desc->wait);
153 set_bit(WDM_READ, &desc->flags);
154 spin_unlock(&desc->iuspin);
157 static void wdm_int_callback(struct urb *urb)
160 int status = urb->status;
161 struct wdm_device *desc;
162 struct usb_ctrlrequest *req;
163 struct usb_cdc_notification *dr;
167 dr = (struct usb_cdc_notification *)desc->sbuf;
176 set_bit(WDM_INT_STALL, &desc->flags);
177 dev_err(&desc->intf->dev, "Stall on int endpoint\n");
178 goto sw; /* halt is cleared in work */
180 dev_err(&desc->intf->dev,
181 "nonzero urb status received: %d\n", status);
186 if (urb->actual_length < sizeof(struct usb_cdc_notification)) {
187 dev_err(&desc->intf->dev, "wdm_int_callback - %d bytes\n",
192 switch (dr->bNotificationType) {
193 case USB_CDC_NOTIFY_RESPONSE_AVAILABLE:
194 dev_dbg(&desc->intf->dev,
195 "NOTIFY_RESPONSE_AVAILABLE received: index %d len %d",
196 dr->wIndex, dr->wLength);
199 case USB_CDC_NOTIFY_NETWORK_CONNECTION:
201 dev_dbg(&desc->intf->dev,
202 "NOTIFY_NETWORK_CONNECTION %s network",
203 dr->wValue ? "connected to" : "disconnected from");
206 clear_bit(WDM_POLL_RUNNING, &desc->flags);
207 dev_err(&desc->intf->dev,
208 "unknown notification %d received: index %d len %d\n",
209 dr->bNotificationType, dr->wIndex, dr->wLength);
213 req->bRequestType = (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE);
214 req->bRequest = USB_CDC_GET_ENCAPSULATED_RESPONSE;
216 req->wIndex = desc->inum;
217 req->wLength = cpu_to_le16(desc->wMaxCommand);
219 usb_fill_control_urb(
221 interface_to_usbdev(desc->intf),
222 /* using common endpoint 0 */
223 usb_rcvctrlpipe(interface_to_usbdev(desc->intf), 0),
224 (unsigned char *)req,
230 desc->response->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
231 spin_lock(&desc->iuspin);
232 clear_bit(WDM_READ, &desc->flags);
233 set_bit(WDM_RESPONDING, &desc->flags);
234 if (!test_bit(WDM_DISCONNECTING, &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)
278 usb_buffer_free(interface_to_usbdev(desc->intf),
279 desc->wMaxPacketSize,
281 desc->validity->transfer_dma);
282 usb_buffer_free(interface_to_usbdev(desc->intf),
285 desc->response->transfer_dma);
293 static ssize_t wdm_write
294 (struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
297 int rv = -EMSGSIZE, r, we;
298 struct wdm_device *desc = file->private_data;
299 struct usb_ctrlrequest *req;
301 if (count > desc->wMaxCommand)
302 count = desc->wMaxCommand;
304 spin_lock_irq(&desc->iuspin);
307 spin_unlock_irq(&desc->iuspin);
311 desc->outbuf = buf = kmalloc(count, GFP_KERNEL);
317 r = copy_from_user(buf, buffer, count);
324 /* concurrent writes and disconnect */
325 r = mutex_lock_interruptible(&desc->lock);
332 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
338 r = usb_autopm_get_interface(desc->intf);
344 if (!file->f_flags && O_NONBLOCK)
345 r = wait_event_interruptible(desc->wait, !test_bit(WDM_IN_USE,
348 if (test_bit(WDM_IN_USE, &desc->flags))
356 usb_fill_control_urb(
358 interface_to_usbdev(desc->intf),
359 /* using common endpoint 0 */
360 usb_sndctrlpipe(interface_to_usbdev(desc->intf), 0),
361 (unsigned char *)req,
368 req->bRequestType = (USB_DIR_OUT | USB_TYPE_CLASS |
369 USB_RECIP_INTERFACE);
370 req->bRequest = USB_CDC_SEND_ENCAPSULATED_COMMAND;
372 req->wIndex = desc->inum;
373 req->wLength = cpu_to_le16(count);
374 set_bit(WDM_IN_USE, &desc->flags);
376 rv = usb_submit_urb(desc->command, GFP_KERNEL);
379 clear_bit(WDM_IN_USE, &desc->flags);
380 dev_err(&desc->intf->dev, "Tx URB error: %d\n", rv);
382 dev_dbg(&desc->intf->dev, "Tx URB has been submitted index=%d",
386 usb_autopm_put_interface(desc->intf);
388 mutex_unlock(&desc->lock);
390 return rv < 0 ? rv : count;
393 static ssize_t wdm_read
394 (struct file *file, char __user *buffer, size_t count, loff_t *ppos)
398 struct wdm_device *desc = file->private_data;
401 rv = mutex_lock_interruptible(&desc->lock); /*concurrent reads */
405 if (desc->length == 0) {
408 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
413 if (file->f_flags & O_NONBLOCK) {
414 if (!test_bit(WDM_READ, &desc->flags)) {
415 rv = cntr ? cntr : -EAGAIN;
420 rv = wait_event_interruptible(desc->wait,
421 test_bit(WDM_READ, &desc->flags));
424 /* may have happened while we slept */
425 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
429 usb_mark_last_busy(interface_to_usbdev(desc->intf));
435 spin_lock_irq(&desc->iuspin);
437 if (desc->rerr) { /* read completed, error happened */
440 spin_unlock_irq(&desc->iuspin);
441 dev_err(&desc->intf->dev,
442 "reading had resulted in %d\n", t);
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);
458 clear_bit(WDM_READ, &desc->flags);
459 spin_unlock_irq(&desc->iuspin);
462 cntr = count > desc->length ? desc->length : count;
463 rv = copy_to_user(buffer, desc->ubuf, cntr);
469 for (i = 0; i < desc->length - cntr; i++)
470 desc->ubuf[i] = desc->ubuf[i + cntr];
472 desc->length -= cntr;
473 /* in case we had outstanding data */
475 clear_bit(WDM_READ, &desc->flags);
479 mutex_unlock(&desc->lock);
480 if (rv < 0 && rv != -EAGAIN)
481 dev_err(&desc->intf->dev, "wdm_read: exit error\n");
485 static int wdm_flush(struct file *file, fl_owner_t id)
487 struct wdm_device *desc = file->private_data;
489 wait_event(desc->wait, !test_bit(WDM_IN_USE, &desc->flags));
491 dev_err(&desc->intf->dev, "Error in flush path: %d\n",
497 static unsigned int wdm_poll(struct file *file, struct poll_table_struct *wait)
499 struct wdm_device *desc = file->private_data;
501 unsigned int mask = 0;
503 spin_lock_irqsave(&desc->iuspin, flags);
504 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
506 spin_unlock_irqrestore(&desc->iuspin, flags);
509 if (test_bit(WDM_READ, &desc->flags))
510 mask = POLLIN | POLLRDNORM;
511 if (desc->rerr || desc->werr)
513 if (!test_bit(WDM_IN_USE, &desc->flags))
514 mask |= POLLOUT | POLLWRNORM;
515 spin_unlock_irqrestore(&desc->iuspin, flags);
517 poll_wait(file, &desc->wait, wait);
523 static int wdm_open(struct inode *inode, struct file *file)
525 int minor = iminor(inode);
527 struct usb_interface *intf;
528 struct wdm_device *desc;
530 mutex_lock(&wdm_mutex);
531 intf = usb_find_interface(&wdm_driver, minor);
535 desc = usb_get_intfdata(intf);
536 if (test_bit(WDM_DISCONNECTING, &desc->flags))
538 file->private_data = desc;
540 rv = usb_autopm_get_interface(desc->intf);
542 dev_err(&desc->intf->dev, "Error autopm - %d\n", rv);
545 intf->needs_remote_wakeup = 1;
547 mutex_lock(&desc->lock);
548 if (!desc->count++) {
549 rv = usb_submit_urb(desc->validity, GFP_KERNEL);
552 dev_err(&desc->intf->dev,
553 "Error submitting int urb - %d\n", rv);
558 mutex_unlock(&desc->lock);
559 usb_autopm_put_interface(desc->intf);
561 mutex_unlock(&wdm_mutex);
565 static int wdm_release(struct inode *inode, struct file *file)
567 struct wdm_device *desc = file->private_data;
569 mutex_lock(&wdm_mutex);
570 mutex_lock(&desc->lock);
572 mutex_unlock(&desc->lock);
575 dev_dbg(&desc->intf->dev, "wdm_release: cleanup");
577 if (!test_bit(WDM_DISCONNECTING, &desc->flags))
578 desc->intf->needs_remote_wakeup = 0;
580 mutex_unlock(&wdm_mutex);
584 static const struct file_operations wdm_fops = {
585 .owner = THIS_MODULE,
590 .release = wdm_release,
594 static struct usb_class_driver wdm_class = {
597 .minor_base = WDM_MINOR_BASE,
600 /* --- error handling --- */
601 static void wdm_rxwork(struct work_struct *work)
603 struct wdm_device *desc = container_of(work, struct wdm_device, rxwork);
607 spin_lock_irqsave(&desc->iuspin, flags);
608 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
609 spin_unlock_irqrestore(&desc->iuspin, flags);
611 spin_unlock_irqrestore(&desc->iuspin, flags);
612 rv = usb_submit_urb(desc->response, GFP_KERNEL);
613 if (rv < 0 && rv != -EPERM) {
614 spin_lock_irqsave(&desc->iuspin, flags);
615 if (!test_bit(WDM_DISCONNECTING, &desc->flags))
616 schedule_work(&desc->rxwork);
617 spin_unlock_irqrestore(&desc->iuspin, flags);
622 /* --- hotplug --- */
624 static int wdm_probe(struct usb_interface *intf, const struct usb_device_id *id)
627 struct usb_device *udev = interface_to_usbdev(intf);
628 struct wdm_device *desc;
629 struct usb_host_interface *iface;
630 struct usb_endpoint_descriptor *ep;
631 struct usb_cdc_dmm_desc *dmhd;
632 u8 *buffer = intf->altsetting->extra;
633 int buflen = intf->altsetting->extralen;
640 if (buffer [1] != USB_DT_CS_INTERFACE) {
641 dev_err(&intf->dev, "skipping garbage\n");
645 switch (buffer [2]) {
646 case USB_CDC_HEADER_TYPE:
648 case USB_CDC_DMM_TYPE:
649 dmhd = (struct usb_cdc_dmm_desc *)buffer;
650 maxcom = le16_to_cpu(dmhd->wMaxCommand);
652 "Finding maximum buffer length: %d", maxcom);
656 "Ignoring extra header, type %d, length %d\n",
657 buffer[2], buffer[0]);
666 desc = kzalloc(sizeof(struct wdm_device), GFP_KERNEL);
669 mutex_init(&desc->lock);
670 spin_lock_init(&desc->iuspin);
671 init_waitqueue_head(&desc->wait);
672 desc->wMaxCommand = maxcom;
673 /* this will be expanded and needed in hardware endianness */
674 desc->inum = cpu_to_le16((u16)intf->cur_altsetting->desc.bInterfaceNumber);
676 INIT_WORK(&desc->rxwork, wdm_rxwork);
679 iface = intf->cur_altsetting;
680 if (iface->desc.bNumEndpoints != 1)
682 ep = &iface->endpoint[0].desc;
683 if (!ep || !usb_endpoint_is_int_in(ep))
686 desc->wMaxPacketSize = le16_to_cpu(ep->wMaxPacketSize);
687 desc->bMaxPacketSize0 = udev->descriptor.bMaxPacketSize0;
689 desc->orq = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
692 desc->irq = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
696 desc->validity = usb_alloc_urb(0, GFP_KERNEL);
700 desc->response = usb_alloc_urb(0, GFP_KERNEL);
704 desc->command = usb_alloc_urb(0, GFP_KERNEL);
708 desc->ubuf = kmalloc(desc->wMaxCommand, GFP_KERNEL);
712 desc->sbuf = usb_buffer_alloc(interface_to_usbdev(intf),
713 desc->wMaxPacketSize,
715 &desc->validity->transfer_dma);
719 desc->inbuf = usb_buffer_alloc(interface_to_usbdev(intf),
720 desc->bMaxPacketSize0,
722 &desc->response->transfer_dma);
728 interface_to_usbdev(intf),
729 usb_rcvintpipe(interface_to_usbdev(intf), ep->bEndpointAddress),
731 desc->wMaxPacketSize,
736 desc->validity->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
738 usb_set_intfdata(intf, desc);
739 rv = usb_register_dev(intf, &wdm_class);
743 dev_info(&intf->dev, "cdc-wdm%d: USB WDM device\n",
744 intf->minor - WDM_MINOR_BASE);
748 usb_set_intfdata(intf, NULL);
749 usb_buffer_free(interface_to_usbdev(desc->intf),
750 desc->bMaxPacketSize0,
752 desc->response->transfer_dma);
754 usb_buffer_free(interface_to_usbdev(desc->intf),
755 desc->wMaxPacketSize,
757 desc->validity->transfer_dma);
767 static void wdm_disconnect(struct usb_interface *intf)
769 struct wdm_device *desc;
772 usb_deregister_dev(intf, &wdm_class);
773 mutex_lock(&wdm_mutex);
774 desc = usb_get_intfdata(intf);
776 /* the spinlock makes sure no new urbs are generated in the callbacks */
777 spin_lock_irqsave(&desc->iuspin, flags);
778 set_bit(WDM_DISCONNECTING, &desc->flags);
779 set_bit(WDM_READ, &desc->flags);
780 /* to terminate pending flushes */
781 clear_bit(WDM_IN_USE, &desc->flags);
782 spin_unlock_irqrestore(&desc->iuspin, flags);
783 cancel_work_sync(&desc->rxwork);
784 mutex_lock(&desc->lock);
786 mutex_unlock(&desc->lock);
787 wake_up_all(&desc->wait);
790 mutex_unlock(&wdm_mutex);
793 static int wdm_suspend(struct usb_interface *intf, pm_message_t message)
795 struct wdm_device *desc = usb_get_intfdata(intf);
798 dev_dbg(&desc->intf->dev, "wdm%d_suspend\n", intf->minor);
800 mutex_lock(&desc->lock);
802 if ((message.event & PM_EVENT_AUTO) &&
803 (test_bit(WDM_IN_USE, &desc->flags)
804 || test_bit(WDM_RESPONDING, &desc->flags))) {
808 cancel_work_sync(&desc->rxwork);
813 mutex_unlock(&desc->lock);
818 static int recover_from_urb_loss(struct wdm_device *desc)
823 rv = usb_submit_urb(desc->validity, GFP_NOIO);
825 dev_err(&desc->intf->dev,
826 "Error resume submitting int urb - %d\n", rv);
830 static int wdm_resume(struct usb_interface *intf)
832 struct wdm_device *desc = usb_get_intfdata(intf);
835 dev_dbg(&desc->intf->dev, "wdm%d_resume\n", intf->minor);
836 mutex_lock(&desc->lock);
837 rv = recover_from_urb_loss(desc);
838 mutex_unlock(&desc->lock);
842 static int wdm_pre_reset(struct usb_interface *intf)
844 struct wdm_device *desc = usb_get_intfdata(intf);
846 mutex_lock(&desc->lock);
850 static int wdm_post_reset(struct usb_interface *intf)
852 struct wdm_device *desc = usb_get_intfdata(intf);
855 rv = recover_from_urb_loss(desc);
856 mutex_unlock(&desc->lock);
860 static struct usb_driver wdm_driver = {
863 .disconnect = wdm_disconnect,
864 .suspend = wdm_suspend,
865 .resume = wdm_resume,
866 .reset_resume = wdm_resume,
867 .pre_reset = wdm_pre_reset,
868 .post_reset = wdm_post_reset,
870 .supports_autosuspend = 1,
873 /* --- low level module stuff --- */
875 static int __init wdm_init(void)
879 rv = usb_register(&wdm_driver);
884 static void __exit wdm_exit(void)
886 usb_deregister(&wdm_driver);
889 module_init(wdm_init);
890 module_exit(wdm_exit);
892 MODULE_AUTHOR(DRIVER_AUTHOR);
893 MODULE_DESCRIPTION(DRIVER_DESC);
894 MODULE_LICENSE("GPL");