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 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
60 static DEFINE_MUTEX(wdm_mutex);
62 /* --- method tables --- */
65 u8 *inbuf; /* buffer for response */
66 u8 *outbuf; /* buffer for command */
67 u8 *sbuf; /* buffer for status */
68 u8 *ubuf; /* buffer for copy to user space */
73 struct usb_interface *intf;
74 struct usb_ctrlrequest *orq;
75 struct usb_ctrlrequest *irq;
93 wait_queue_head_t wait;
94 struct work_struct rxwork;
99 static struct usb_driver wdm_driver;
101 /* --- callbacks --- */
102 static void wdm_out_callback(struct urb *urb)
104 struct wdm_device *desc;
106 spin_lock(&desc->iuspin);
107 desc->werr = urb->status;
108 spin_unlock(&desc->iuspin);
109 clear_bit(WDM_IN_USE, &desc->flags);
111 wake_up(&desc->wait);
114 static void wdm_in_callback(struct urb *urb)
116 struct wdm_device *desc = urb->context;
117 int status = urb->status;
119 spin_lock(&desc->iuspin);
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;
150 wake_up(&desc->wait);
152 set_bit(WDM_READ, &desc->flags);
153 spin_unlock(&desc->iuspin);
156 static void wdm_int_callback(struct urb *urb)
159 int status = urb->status;
160 struct wdm_device *desc;
161 struct usb_ctrlrequest *req;
162 struct usb_cdc_notification *dr;
166 dr = (struct usb_cdc_notification *)desc->sbuf;
175 set_bit(WDM_INT_STALL, &desc->flags);
176 dev_err(&desc->intf->dev, "Stall on int endpoint\n");
177 goto sw; /* halt is cleared in work */
179 dev_err(&desc->intf->dev,
180 "nonzero urb status received: %d\n", status);
185 if (urb->actual_length < sizeof(struct usb_cdc_notification)) {
186 dev_err(&desc->intf->dev, "wdm_int_callback - %d bytes\n",
191 switch (dr->bNotificationType) {
192 case USB_CDC_NOTIFY_RESPONSE_AVAILABLE:
193 dev_dbg(&desc->intf->dev,
194 "NOTIFY_RESPONSE_AVAILABLE received: index %d len %d",
195 dr->wIndex, dr->wLength);
198 case USB_CDC_NOTIFY_NETWORK_CONNECTION:
200 dev_dbg(&desc->intf->dev,
201 "NOTIFY_NETWORK_CONNECTION %s network",
202 dr->wValue ? "connected to" : "disconnected from");
205 clear_bit(WDM_POLL_RUNNING, &desc->flags);
206 dev_err(&desc->intf->dev,
207 "unknown notification %d received: index %d len %d\n",
208 dr->bNotificationType, dr->wIndex, dr->wLength);
212 req->bRequestType = (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE);
213 req->bRequest = USB_CDC_GET_ENCAPSULATED_RESPONSE;
215 req->wIndex = desc->inum;
216 req->wLength = cpu_to_le16(desc->wMaxCommand);
218 usb_fill_control_urb(
220 interface_to_usbdev(desc->intf),
221 /* using common endpoint 0 */
222 usb_rcvctrlpipe(interface_to_usbdev(desc->intf), 0),
223 (unsigned char *)req,
229 desc->response->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
230 spin_lock(&desc->iuspin);
231 clear_bit(WDM_READ, &desc->flags);
232 if (!test_bit(WDM_DISCONNECTING, &desc->flags)) {
233 rv = usb_submit_urb(desc->response, GFP_ATOMIC);
234 dev_dbg(&desc->intf->dev, "%s: usb_submit_urb %d",
237 spin_unlock(&desc->iuspin);
243 rv = schedule_work(&desc->rxwork);
245 dev_err(&desc->intf->dev,
246 "Cannot schedule work\n");
250 rv = usb_submit_urb(urb, GFP_ATOMIC);
252 dev_err(&desc->intf->dev,
253 "%s - usb_submit_urb failed with result %d\n",
258 static void kill_urbs(struct wdm_device *desc)
260 /* the order here is essential */
261 usb_kill_urb(desc->command);
262 usb_kill_urb(desc->validity);
263 usb_kill_urb(desc->response);
266 static void free_urbs(struct wdm_device *desc)
268 usb_free_urb(desc->validity);
269 usb_free_urb(desc->response);
270 usb_free_urb(desc->command);
273 static void cleanup(struct wdm_device *desc)
275 usb_buffer_free(interface_to_usbdev(desc->intf),
276 desc->wMaxPacketSize,
278 desc->validity->transfer_dma);
279 usb_buffer_free(interface_to_usbdev(desc->intf),
282 desc->response->transfer_dma);
290 static ssize_t wdm_write
291 (struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
294 int rv = -EMSGSIZE, r, we;
295 struct wdm_device *desc = file->private_data;
296 struct usb_ctrlrequest *req;
298 if (count > desc->wMaxCommand)
299 count = desc->wMaxCommand;
301 spin_lock_irq(&desc->iuspin);
304 spin_unlock_irq(&desc->iuspin);
308 r = mutex_lock_interruptible(&desc->wlock); /* concurrent writes */
313 r = usb_autopm_get_interface(desc->intf);
316 r = wait_event_interruptible(desc->wait, !test_bit(WDM_IN_USE,
321 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
326 desc->outbuf = buf = kmalloc(count, GFP_KERNEL);
332 r = copy_from_user(buf, buffer, count);
340 usb_fill_control_urb(
342 interface_to_usbdev(desc->intf),
343 /* using common endpoint 0 */
344 usb_sndctrlpipe(interface_to_usbdev(desc->intf), 0),
345 (unsigned char *)req,
352 req->bRequestType = (USB_DIR_OUT | USB_TYPE_CLASS |
353 USB_RECIP_INTERFACE);
354 req->bRequest = USB_CDC_SEND_ENCAPSULATED_COMMAND;
356 req->wIndex = desc->inum;
357 req->wLength = cpu_to_le16(count);
358 set_bit(WDM_IN_USE, &desc->flags);
360 rv = usb_submit_urb(desc->command, GFP_KERNEL);
363 clear_bit(WDM_IN_USE, &desc->flags);
364 dev_err(&desc->intf->dev, "Tx URB error: %d\n", rv);
366 dev_dbg(&desc->intf->dev, "Tx URB has been submitted index=%d",
370 usb_autopm_put_interface(desc->intf);
372 mutex_unlock(&desc->wlock);
374 return rv < 0 ? rv : count;
377 static ssize_t wdm_read
378 (struct file *file, char __user *buffer, size_t count, loff_t *ppos)
382 struct wdm_device *desc = file->private_data;
385 rv = mutex_lock_interruptible(&desc->rlock); /*concurrent reads */
389 if (desc->length == 0) {
393 rv = wait_event_interruptible(desc->wait,
394 test_bit(WDM_READ, &desc->flags));
396 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
400 usb_mark_last_busy(interface_to_usbdev(desc->intf));
406 spin_lock_irq(&desc->iuspin);
408 if (desc->rerr) { /* read completed, error happened */
411 spin_unlock_irq(&desc->iuspin);
412 dev_err(&desc->intf->dev,
413 "reading had resulted in %d\n", t);
418 * recheck whether we've lost the race
419 * against the completion handler
421 if (!test_bit(WDM_READ, &desc->flags)) { /* lost race */
422 spin_unlock_irq(&desc->iuspin);
425 if (!desc->reslength) { /* zero length read */
426 spin_unlock_irq(&desc->iuspin);
429 clear_bit(WDM_READ, &desc->flags);
430 spin_unlock_irq(&desc->iuspin);
433 cntr = count > desc->length ? desc->length : count;
434 rv = copy_to_user(buffer, desc->ubuf, cntr);
440 for (i = 0; i < desc->length - cntr; i++)
441 desc->ubuf[i] = desc->ubuf[i + cntr];
443 desc->length -= cntr;
444 /* in case we had outstanding data */
446 clear_bit(WDM_READ, &desc->flags);
450 mutex_unlock(&desc->rlock);
452 dev_err(&desc->intf->dev, "wdm_read: exit error\n");
456 static int wdm_flush(struct file *file, fl_owner_t id)
458 struct wdm_device *desc = file->private_data;
460 wait_event(desc->wait, !test_bit(WDM_IN_USE, &desc->flags));
462 dev_err(&desc->intf->dev, "Error in flush path: %d\n",
468 static unsigned int wdm_poll(struct file *file, struct poll_table_struct *wait)
470 struct wdm_device *desc = file->private_data;
472 unsigned int mask = 0;
474 spin_lock_irqsave(&desc->iuspin, flags);
475 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
477 spin_unlock_irqrestore(&desc->iuspin, flags);
480 if (test_bit(WDM_READ, &desc->flags))
481 mask = POLLIN | POLLRDNORM;
482 if (desc->rerr || desc->werr)
484 if (!test_bit(WDM_IN_USE, &desc->flags))
485 mask |= POLLOUT | POLLWRNORM;
486 spin_unlock_irqrestore(&desc->iuspin, flags);
488 poll_wait(file, &desc->wait, wait);
494 static int wdm_open(struct inode *inode, struct file *file)
496 int minor = iminor(inode);
498 struct usb_interface *intf;
499 struct wdm_device *desc;
501 mutex_lock(&wdm_mutex);
502 intf = usb_find_interface(&wdm_driver, minor);
506 desc = usb_get_intfdata(intf);
507 if (test_bit(WDM_DISCONNECTING, &desc->flags))
511 file->private_data = desc;
513 rv = usb_autopm_get_interface(desc->intf);
515 dev_err(&desc->intf->dev, "Error autopm - %d\n", rv);
518 intf->needs_remote_wakeup = 1;
520 mutex_lock(&desc->plock);
521 if (!desc->count++) {
522 rv = usb_submit_urb(desc->validity, GFP_KERNEL);
525 dev_err(&desc->intf->dev,
526 "Error submitting int urb - %d\n", rv);
531 mutex_unlock(&desc->plock);
532 usb_autopm_put_interface(desc->intf);
534 mutex_unlock(&wdm_mutex);
538 static int wdm_release(struct inode *inode, struct file *file)
540 struct wdm_device *desc = file->private_data;
542 mutex_lock(&wdm_mutex);
543 mutex_lock(&desc->plock);
545 mutex_unlock(&desc->plock);
548 dev_dbg(&desc->intf->dev, "wdm_release: cleanup");
550 if (!test_bit(WDM_DISCONNECTING, &desc->flags))
551 desc->intf->needs_remote_wakeup = 0;
553 mutex_unlock(&wdm_mutex);
557 static const struct file_operations wdm_fops = {
558 .owner = THIS_MODULE,
563 .release = wdm_release,
567 static struct usb_class_driver wdm_class = {
570 .minor_base = WDM_MINOR_BASE,
573 /* --- error handling --- */
574 static void wdm_rxwork(struct work_struct *work)
576 struct wdm_device *desc = container_of(work, struct wdm_device, rxwork);
580 spin_lock_irqsave(&desc->iuspin, flags);
581 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
582 spin_unlock_irqrestore(&desc->iuspin, flags);
584 spin_unlock_irqrestore(&desc->iuspin, flags);
585 rv = usb_submit_urb(desc->response, GFP_KERNEL);
586 if (rv < 0 && rv != -EPERM) {
587 spin_lock_irqsave(&desc->iuspin, flags);
588 if (!test_bit(WDM_DISCONNECTING, &desc->flags))
589 schedule_work(&desc->rxwork);
590 spin_unlock_irqrestore(&desc->iuspin, flags);
595 /* --- hotplug --- */
597 static int wdm_probe(struct usb_interface *intf, const struct usb_device_id *id)
600 struct usb_device *udev = interface_to_usbdev(intf);
601 struct wdm_device *desc;
602 struct usb_host_interface *iface;
603 struct usb_endpoint_descriptor *ep;
604 struct usb_cdc_dmm_desc *dmhd;
605 u8 *buffer = intf->altsetting->extra;
606 int buflen = intf->altsetting->extralen;
613 if (buffer [1] != USB_DT_CS_INTERFACE) {
614 dev_err(&intf->dev, "skipping garbage\n");
618 switch (buffer [2]) {
619 case USB_CDC_HEADER_TYPE:
621 case USB_CDC_DMM_TYPE:
622 dmhd = (struct usb_cdc_dmm_desc *)buffer;
623 maxcom = le16_to_cpu(dmhd->wMaxCommand);
625 "Finding maximum buffer length: %d", maxcom);
629 "Ignoring extra header, type %d, length %d\n",
630 buffer[2], buffer[0]);
639 desc = kzalloc(sizeof(struct wdm_device), GFP_KERNEL);
642 mutex_init(&desc->wlock);
643 mutex_init(&desc->rlock);
644 mutex_init(&desc->plock);
645 spin_lock_init(&desc->iuspin);
646 init_waitqueue_head(&desc->wait);
647 desc->wMaxCommand = maxcom;
648 /* this will be expanded and needed in hardware endianness */
649 desc->inum = cpu_to_le16((u16)intf->cur_altsetting->desc.bInterfaceNumber);
651 INIT_WORK(&desc->rxwork, wdm_rxwork);
654 iface = intf->cur_altsetting;
655 if (iface->desc.bNumEndpoints != 1)
657 ep = &iface->endpoint[0].desc;
658 if (!ep || !usb_endpoint_is_int_in(ep))
661 desc->wMaxPacketSize = le16_to_cpu(ep->wMaxPacketSize);
662 desc->bMaxPacketSize0 = udev->descriptor.bMaxPacketSize0;
664 desc->orq = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
667 desc->irq = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
671 desc->validity = usb_alloc_urb(0, GFP_KERNEL);
675 desc->response = usb_alloc_urb(0, GFP_KERNEL);
679 desc->command = usb_alloc_urb(0, GFP_KERNEL);
683 desc->ubuf = kmalloc(desc->wMaxCommand, GFP_KERNEL);
687 desc->sbuf = usb_buffer_alloc(interface_to_usbdev(intf),
688 desc->wMaxPacketSize,
690 &desc->validity->transfer_dma);
694 desc->inbuf = usb_buffer_alloc(interface_to_usbdev(intf),
695 desc->bMaxPacketSize0,
697 &desc->response->transfer_dma);
703 interface_to_usbdev(intf),
704 usb_rcvintpipe(interface_to_usbdev(intf), ep->bEndpointAddress),
706 desc->wMaxPacketSize,
711 desc->validity->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
713 usb_set_intfdata(intf, desc);
714 rv = usb_register_dev(intf, &wdm_class);
718 dev_info(&intf->dev, "cdc-wdm%d: USB WDM device\n",
719 intf->minor - WDM_MINOR_BASE);
723 usb_set_intfdata(intf, NULL);
724 usb_buffer_free(interface_to_usbdev(desc->intf),
725 desc->bMaxPacketSize0,
727 desc->response->transfer_dma);
729 usb_buffer_free(interface_to_usbdev(desc->intf),
730 desc->wMaxPacketSize,
732 desc->validity->transfer_dma);
742 static void wdm_disconnect(struct usb_interface *intf)
744 struct wdm_device *desc;
747 usb_deregister_dev(intf, &wdm_class);
748 mutex_lock(&wdm_mutex);
749 desc = usb_get_intfdata(intf);
751 /* the spinlock makes sure no new urbs are generated in the callbacks */
752 spin_lock_irqsave(&desc->iuspin, flags);
753 set_bit(WDM_DISCONNECTING, &desc->flags);
754 set_bit(WDM_READ, &desc->flags);
755 /* to terminate pending flushes */
756 clear_bit(WDM_IN_USE, &desc->flags);
757 spin_unlock_irqrestore(&desc->iuspin, flags);
758 cancel_work_sync(&desc->rxwork);
760 wake_up_all(&desc->wait);
763 mutex_unlock(&wdm_mutex);
766 static int wdm_suspend(struct usb_interface *intf, pm_message_t message)
768 struct wdm_device *desc = usb_get_intfdata(intf);
771 dev_dbg(&desc->intf->dev, "wdm%d_suspend\n", intf->minor);
773 mutex_lock(&desc->plock);
775 if ((message.event & PM_EVENT_AUTO) &&
776 test_bit(WDM_IN_USE, &desc->flags)) {
780 cancel_work_sync(&desc->rxwork);
785 mutex_unlock(&desc->plock);
790 static int recover_from_urb_loss(struct wdm_device *desc)
795 rv = usb_submit_urb(desc->validity, GFP_NOIO);
797 dev_err(&desc->intf->dev,
798 "Error resume submitting int urb - %d\n", rv);
802 static int wdm_resume(struct usb_interface *intf)
804 struct wdm_device *desc = usb_get_intfdata(intf);
807 dev_dbg(&desc->intf->dev, "wdm%d_resume\n", intf->minor);
808 mutex_lock(&desc->plock);
809 rv = recover_from_urb_loss(desc);
810 mutex_unlock(&desc->plock);
814 static int wdm_pre_reset(struct usb_interface *intf)
816 struct wdm_device *desc = usb_get_intfdata(intf);
818 mutex_lock(&desc->plock);
822 static int wdm_post_reset(struct usb_interface *intf)
824 struct wdm_device *desc = usb_get_intfdata(intf);
827 rv = recover_from_urb_loss(desc);
828 mutex_unlock(&desc->plock);
832 static struct usb_driver wdm_driver = {
835 .disconnect = wdm_disconnect,
836 .suspend = wdm_suspend,
837 .resume = wdm_resume,
838 .reset_resume = wdm_resume,
839 .pre_reset = wdm_pre_reset,
840 .post_reset = wdm_post_reset,
842 .supports_autosuspend = 1,
845 /* --- low level module stuff --- */
847 static int __init wdm_init(void)
851 rv = usb_register(&wdm_driver);
856 static void __exit wdm_exit(void)
858 usb_deregister(&wdm_driver);
861 module_init(wdm_init);
862 module_exit(wdm_exit);
864 MODULE_AUTHOR(DRIVER_AUTHOR);
865 MODULE_DESCRIPTION(DRIVER_DESC);
866 MODULE_LICENSE("GPL");