4 * This driver supports USB CDC WCM Device Management.
6 * Copyright (c) 2007-2008 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/smp_lock.h>
19 #include <linux/mutex.h>
20 #include <linux/uaccess.h>
21 #include <linux/bitops.h>
22 #include <linux/poll.h>
23 #include <linux/usb.h>
24 #include <linux/usb/cdc.h>
25 #include <asm/byteorder.h>
26 #include <asm/unaligned.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 static struct usb_device_id wdm_ids[] = {
37 .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS |
38 USB_DEVICE_ID_MATCH_INT_SUBCLASS,
39 .bInterfaceClass = USB_CLASS_COMM,
40 .bInterfaceSubClass = USB_CDC_SUBCLASS_DMM
45 #define WDM_MINOR_BASE 176
49 #define WDM_DISCONNECTING 2
52 #define WDM_INT_STALL 5
53 #define WDM_POLL_RUNNING 6
59 static DEFINE_MUTEX(wdm_mutex);
61 /* --- method tables --- */
64 u8 *inbuf; /* buffer for response */
65 u8 *outbuf; /* buffer for command */
66 u8 *sbuf; /* buffer for status */
67 u8 *ubuf; /* buffer for copy to user space */
72 struct usb_interface *intf;
73 struct usb_ctrlrequest *orq;
74 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);
123 dev_dbg(&desc->intf->dev,
124 "nonzero urb status received: -ENOENT");
127 dev_dbg(&desc->intf->dev,
128 "nonzero urb status received: -ECONNRESET");
131 dev_dbg(&desc->intf->dev,
132 "nonzero urb status received: -ESHUTDOWN");
135 dev_err(&desc->intf->dev,
136 "nonzero urb status received: -EPIPE\n");
139 dev_err(&desc->intf->dev,
140 "Unexpected error %d\n", status);
146 desc->reslength = urb->actual_length;
147 memmove(desc->ubuf + desc->length, desc->inbuf, desc->reslength);
148 desc->length += desc->reslength;
149 wake_up(&desc->wait);
151 set_bit(WDM_READ, &desc->flags);
152 spin_unlock(&desc->iuspin);
155 static void wdm_int_callback(struct urb *urb)
158 int status = urb->status;
159 struct wdm_device *desc;
160 struct usb_ctrlrequest *req;
161 struct usb_cdc_notification *dr;
165 dr = (struct usb_cdc_notification *)desc->sbuf;
174 set_bit(WDM_INT_STALL, &desc->flags);
175 dev_err(&desc->intf->dev, "Stall on int endpoint\n");
176 goto sw; /* halt is cleared in work */
178 dev_err(&desc->intf->dev,
179 "nonzero urb status received: %d\n", status);
184 if (urb->actual_length < sizeof(struct usb_cdc_notification)) {
185 dev_err(&desc->intf->dev, "wdm_int_callback - %d bytes\n",
190 switch (dr->bNotificationType) {
191 case USB_CDC_NOTIFY_RESPONSE_AVAILABLE:
192 dev_dbg(&desc->intf->dev,
193 "NOTIFY_RESPONSE_AVAILABLE received: index %d len %d",
194 dr->wIndex, dr->wLength);
197 case USB_CDC_NOTIFY_NETWORK_CONNECTION:
199 dev_dbg(&desc->intf->dev,
200 "NOTIFY_NETWORK_CONNECTION %s network",
201 dr->wValue ? "connected to" : "disconnected from");
204 clear_bit(WDM_POLL_RUNNING, &desc->flags);
205 dev_err(&desc->intf->dev,
206 "unknown notification %d received: index %d len %d\n",
207 dr->bNotificationType, dr->wIndex, dr->wLength);
211 req->bRequestType = (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE);
212 req->bRequest = USB_CDC_GET_ENCAPSULATED_RESPONSE;
214 req->wIndex = desc->inum;
215 req->wLength = cpu_to_le16(desc->wMaxCommand);
217 usb_fill_control_urb(
219 interface_to_usbdev(desc->intf),
220 /* using common endpoint 0 */
221 usb_rcvctrlpipe(interface_to_usbdev(desc->intf), 0),
222 (unsigned char *)req,
228 desc->response->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
229 spin_lock(&desc->iuspin);
230 clear_bit(WDM_READ, &desc->flags);
231 if (!test_bit(WDM_DISCONNECTING, &desc->flags)) {
232 rv = usb_submit_urb(desc->response, GFP_ATOMIC);
233 dev_dbg(&desc->intf->dev, "%s: usb_submit_urb %d",
236 spin_unlock(&desc->iuspin);
242 rv = schedule_work(&desc->rxwork);
244 dev_err(&desc->intf->dev,
245 "Cannot schedule work\n");
249 rv = usb_submit_urb(urb, GFP_ATOMIC);
251 dev_err(&desc->intf->dev,
252 "%s - usb_submit_urb failed with result %d\n",
257 static void kill_urbs(struct wdm_device *desc)
259 /* the order here is essential */
260 usb_kill_urb(desc->command);
261 usb_kill_urb(desc->validity);
262 usb_kill_urb(desc->response);
265 static void free_urbs(struct wdm_device *desc)
267 usb_free_urb(desc->validity);
268 usb_free_urb(desc->response);
269 usb_free_urb(desc->command);
272 static void cleanup(struct wdm_device *desc)
274 usb_buffer_free(interface_to_usbdev(desc->intf),
275 desc->wMaxPacketSize,
277 desc->validity->transfer_dma);
278 usb_buffer_free(interface_to_usbdev(desc->intf),
281 desc->response->transfer_dma);
289 static ssize_t wdm_write
290 (struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
293 int rv = -EMSGSIZE, r, we;
294 struct wdm_device *desc = file->private_data;
295 struct usb_ctrlrequest *req;
297 if (count > desc->wMaxCommand)
298 count = desc->wMaxCommand;
300 spin_lock_irq(&desc->iuspin);
303 spin_unlock_irq(&desc->iuspin);
307 r = mutex_lock_interruptible(&desc->wlock); /* concurrent writes */
312 r = usb_autopm_get_interface(desc->intf);
315 r = wait_event_interruptible(desc->wait, !test_bit(WDM_IN_USE,
320 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
325 desc->outbuf = buf = kmalloc(count, GFP_KERNEL);
331 r = copy_from_user(buf, buffer, count);
339 usb_fill_control_urb(
341 interface_to_usbdev(desc->intf),
342 /* using common endpoint 0 */
343 usb_sndctrlpipe(interface_to_usbdev(desc->intf), 0),
344 (unsigned char *)req,
351 req->bRequestType = (USB_DIR_OUT | USB_TYPE_CLASS |
352 USB_RECIP_INTERFACE);
353 req->bRequest = USB_CDC_SEND_ENCAPSULATED_COMMAND;
355 req->wIndex = desc->inum;
356 req->wLength = cpu_to_le16(count);
357 set_bit(WDM_IN_USE, &desc->flags);
359 rv = usb_submit_urb(desc->command, GFP_KERNEL);
362 clear_bit(WDM_IN_USE, &desc->flags);
363 dev_err(&desc->intf->dev, "Tx URB error: %d\n", rv);
365 dev_dbg(&desc->intf->dev, "Tx URB has been submitted index=%d",
369 usb_autopm_put_interface(desc->intf);
371 mutex_unlock(&desc->wlock);
373 return rv < 0 ? rv : count;
376 static ssize_t wdm_read
377 (struct file *file, char __user *buffer, size_t count, loff_t *ppos)
381 struct wdm_device *desc = file->private_data;
384 rv = mutex_lock_interruptible(&desc->rlock); /*concurrent reads */
388 if (desc->length == 0) {
392 rv = wait_event_interruptible(desc->wait,
393 test_bit(WDM_READ, &desc->flags));
395 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
399 usb_mark_last_busy(interface_to_usbdev(desc->intf));
405 spin_lock_irq(&desc->iuspin);
407 if (desc->rerr) { /* read completed, error happened */
410 spin_unlock_irq(&desc->iuspin);
411 dev_err(&desc->intf->dev,
412 "reading had resulted in %d\n", t);
417 * recheck whether we've lost the race
418 * against the completion handler
420 if (!test_bit(WDM_READ, &desc->flags)) { /* lost race */
421 spin_unlock_irq(&desc->iuspin);
424 if (!desc->reslength) { /* zero length read */
425 spin_unlock_irq(&desc->iuspin);
428 clear_bit(WDM_READ, &desc->flags);
429 spin_unlock_irq(&desc->iuspin);
432 cntr = count > desc->length ? desc->length : count;
433 rv = copy_to_user(buffer, desc->ubuf, cntr);
439 for (i = 0; i < desc->length - cntr; i++)
440 desc->ubuf[i] = desc->ubuf[i + cntr];
442 desc->length -= cntr;
443 /* in case we had outstanding data */
445 clear_bit(WDM_READ, &desc->flags);
449 mutex_unlock(&desc->rlock);
451 dev_err(&desc->intf->dev, "wdm_read: exit error\n");
455 static int wdm_flush(struct file *file, fl_owner_t id)
457 struct wdm_device *desc = file->private_data;
459 wait_event(desc->wait, !test_bit(WDM_IN_USE, &desc->flags));
461 dev_err(&desc->intf->dev, "Error in flush path: %d\n",
467 static unsigned int wdm_poll(struct file *file, struct poll_table_struct *wait)
469 struct wdm_device *desc = file->private_data;
471 unsigned int mask = 0;
473 spin_lock_irqsave(&desc->iuspin, flags);
474 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
476 spin_unlock_irqrestore(&desc->iuspin, flags);
479 if (test_bit(WDM_READ, &desc->flags))
480 mask = POLLIN | POLLRDNORM;
481 if (desc->rerr || desc->werr)
483 if (!test_bit(WDM_IN_USE, &desc->flags))
484 mask |= POLLOUT | POLLWRNORM;
485 spin_unlock_irqrestore(&desc->iuspin, flags);
487 poll_wait(file, &desc->wait, wait);
493 static int wdm_open(struct inode *inode, struct file *file)
495 int minor = iminor(inode);
497 struct usb_interface *intf;
498 struct wdm_device *desc;
500 mutex_lock(&wdm_mutex);
501 intf = usb_find_interface(&wdm_driver, minor);
505 desc = usb_get_intfdata(intf);
506 if (test_bit(WDM_DISCONNECTING, &desc->flags))
510 file->private_data = desc;
512 rv = usb_autopm_get_interface(desc->intf);
514 dev_err(&desc->intf->dev, "Error autopm - %d\n", rv);
517 intf->needs_remote_wakeup = 1;
519 mutex_lock(&desc->plock);
520 if (!desc->count++) {
521 rv = usb_submit_urb(desc->validity, GFP_KERNEL);
524 dev_err(&desc->intf->dev,
525 "Error submitting int urb - %d\n", rv);
530 mutex_unlock(&desc->plock);
531 usb_autopm_put_interface(desc->intf);
533 mutex_unlock(&wdm_mutex);
537 static int wdm_release(struct inode *inode, struct file *file)
539 struct wdm_device *desc = file->private_data;
541 mutex_lock(&wdm_mutex);
542 mutex_lock(&desc->plock);
544 mutex_unlock(&desc->plock);
547 dev_dbg(&desc->intf->dev, "wdm_release: cleanup");
549 if (!test_bit(WDM_DISCONNECTING, &desc->flags))
550 desc->intf->needs_remote_wakeup = 0;
552 mutex_unlock(&wdm_mutex);
556 static const struct file_operations wdm_fops = {
557 .owner = THIS_MODULE,
562 .release = wdm_release,
566 static struct usb_class_driver wdm_class = {
569 .minor_base = WDM_MINOR_BASE,
572 /* --- error handling --- */
573 static void wdm_rxwork(struct work_struct *work)
575 struct wdm_device *desc = container_of(work, struct wdm_device, rxwork);
579 spin_lock_irqsave(&desc->iuspin, flags);
580 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
581 spin_unlock_irqrestore(&desc->iuspin, flags);
583 spin_unlock_irqrestore(&desc->iuspin, flags);
584 rv = usb_submit_urb(desc->response, GFP_KERNEL);
585 if (rv < 0 && rv != -EPERM) {
586 spin_lock_irqsave(&desc->iuspin, flags);
587 if (!test_bit(WDM_DISCONNECTING, &desc->flags))
588 schedule_work(&desc->rxwork);
589 spin_unlock_irqrestore(&desc->iuspin, flags);
594 /* --- hotplug --- */
596 static int wdm_probe(struct usb_interface *intf, const struct usb_device_id *id)
599 struct usb_device *udev = interface_to_usbdev(intf);
600 struct wdm_device *desc;
601 struct usb_host_interface *iface;
602 struct usb_endpoint_descriptor *ep;
603 struct usb_cdc_dmm_desc *dmhd;
604 u8 *buffer = intf->altsetting->extra;
605 int buflen = intf->altsetting->extralen;
612 if (buffer [1] != USB_DT_CS_INTERFACE) {
613 dev_err(&intf->dev, "skipping garbage\n");
617 switch (buffer [2]) {
618 case USB_CDC_HEADER_TYPE:
620 case USB_CDC_DMM_TYPE:
621 dmhd = (struct usb_cdc_dmm_desc *)buffer;
622 maxcom = le16_to_cpu(dmhd->wMaxCommand);
624 "Finding maximum buffer length: %d", maxcom);
628 "Ignoring extra header, type %d, length %d\n",
629 buffer[2], buffer[0]);
638 desc = kzalloc(sizeof(struct wdm_device), GFP_KERNEL);
641 mutex_init(&desc->wlock);
642 mutex_init(&desc->rlock);
643 mutex_init(&desc->plock);
644 spin_lock_init(&desc->iuspin);
645 init_waitqueue_head(&desc->wait);
646 desc->wMaxCommand = maxcom;
647 desc->inum = cpu_to_le16((u16)intf->cur_altsetting->desc.bInterfaceNumber);
649 INIT_WORK(&desc->rxwork, wdm_rxwork);
651 iface = &intf->altsetting[0];
652 ep = &iface->endpoint[0].desc;
653 if (!usb_endpoint_is_int_in(ep)) {
658 desc->wMaxPacketSize = le16_to_cpu(ep->wMaxPacketSize);
659 desc->bMaxPacketSize0 = udev->descriptor.bMaxPacketSize0;
661 desc->orq = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
664 desc->irq = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
668 desc->validity = usb_alloc_urb(0, GFP_KERNEL);
672 desc->response = usb_alloc_urb(0, GFP_KERNEL);
676 desc->command = usb_alloc_urb(0, GFP_KERNEL);
680 desc->ubuf = kmalloc(desc->wMaxCommand, GFP_KERNEL);
684 desc->sbuf = usb_buffer_alloc(interface_to_usbdev(intf),
685 desc->wMaxPacketSize,
687 &desc->validity->transfer_dma);
691 desc->inbuf = usb_buffer_alloc(interface_to_usbdev(intf),
692 desc->bMaxPacketSize0,
694 &desc->response->transfer_dma);
700 interface_to_usbdev(intf),
701 usb_rcvintpipe(interface_to_usbdev(intf), ep->bEndpointAddress),
703 desc->wMaxPacketSize,
708 desc->validity->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
710 usb_set_intfdata(intf, desc);
711 rv = usb_register_dev(intf, &wdm_class);
712 dev_info(&intf->dev, "cdc-wdm%d: USB WDM device\n",
713 intf->minor - WDM_MINOR_BASE);
719 usb_buffer_free(interface_to_usbdev(desc->intf),
720 desc->wMaxPacketSize,
722 desc->validity->transfer_dma);
732 static void wdm_disconnect(struct usb_interface *intf)
734 struct wdm_device *desc;
737 usb_deregister_dev(intf, &wdm_class);
738 mutex_lock(&wdm_mutex);
739 desc = usb_get_intfdata(intf);
741 /* the spinlock makes sure no new urbs are generated in the callbacks */
742 spin_lock_irqsave(&desc->iuspin, flags);
743 set_bit(WDM_DISCONNECTING, &desc->flags);
744 set_bit(WDM_READ, &desc->flags);
745 /* to terminate pending flushes */
746 clear_bit(WDM_IN_USE, &desc->flags);
747 spin_unlock_irqrestore(&desc->iuspin, flags);
748 cancel_work_sync(&desc->rxwork);
750 wake_up_all(&desc->wait);
753 mutex_unlock(&wdm_mutex);
756 static int wdm_suspend(struct usb_interface *intf, pm_message_t message)
758 struct wdm_device *desc = usb_get_intfdata(intf);
761 dev_dbg(&desc->intf->dev, "wdm%d_suspend\n", intf->minor);
763 mutex_lock(&desc->plock);
765 if (interface_to_usbdev(desc->intf)->auto_pm && test_bit(WDM_IN_USE, &desc->flags)) {
769 cancel_work_sync(&desc->rxwork);
774 mutex_unlock(&desc->plock);
779 static int recover_from_urb_loss(struct wdm_device *desc)
784 rv = usb_submit_urb(desc->validity, GFP_NOIO);
786 dev_err(&desc->intf->dev,
787 "Error resume submitting int urb - %d\n", rv);
791 static int wdm_resume(struct usb_interface *intf)
793 struct wdm_device *desc = usb_get_intfdata(intf);
796 dev_dbg(&desc->intf->dev, "wdm%d_resume\n", intf->minor);
797 mutex_lock(&desc->plock);
798 rv = recover_from_urb_loss(desc);
799 mutex_unlock(&desc->plock);
803 static int wdm_pre_reset(struct usb_interface *intf)
805 struct wdm_device *desc = usb_get_intfdata(intf);
807 mutex_lock(&desc->plock);
811 static int wdm_post_reset(struct usb_interface *intf)
813 struct wdm_device *desc = usb_get_intfdata(intf);
816 rv = recover_from_urb_loss(desc);
817 mutex_unlock(&desc->plock);
821 static struct usb_driver wdm_driver = {
824 .disconnect = wdm_disconnect,
825 .suspend = wdm_suspend,
826 .resume = wdm_resume,
827 .reset_resume = wdm_resume,
828 .pre_reset = wdm_pre_reset,
829 .post_reset = wdm_post_reset,
831 .supports_autosuspend = 1,
834 /* --- low level module stuff --- */
836 static int __init wdm_init(void)
840 rv = usb_register(&wdm_driver);
845 static void __exit wdm_exit(void)
847 usb_deregister(&wdm_driver);
850 module_init(wdm_init);
851 module_exit(wdm_exit);
853 MODULE_AUTHOR(DRIVER_AUTHOR);
854 MODULE_DESCRIPTION(DRIVER_DESC);
855 MODULE_LICENSE("GPL");