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;
91 wait_queue_head_t wait;
92 struct work_struct rxwork;
97 static struct usb_driver wdm_driver;
99 /* --- callbacks --- */
100 static void wdm_out_callback(struct urb *urb)
102 struct wdm_device *desc;
104 spin_lock(&desc->iuspin);
105 desc->werr = urb->status;
106 spin_unlock(&desc->iuspin);
107 clear_bit(WDM_IN_USE, &desc->flags);
109 wake_up(&desc->wait);
112 static void wdm_in_callback(struct urb *urb)
114 struct wdm_device *desc = urb->context;
115 int status = urb->status;
117 spin_lock(&desc->iuspin);
122 dev_dbg(&desc->intf->dev,
123 "nonzero urb status received: -ENOENT");
126 dev_dbg(&desc->intf->dev,
127 "nonzero urb status received: -ECONNRESET");
130 dev_dbg(&desc->intf->dev,
131 "nonzero urb status received: -ESHUTDOWN");
134 err("nonzero urb status received: -EPIPE");
137 err("Unexpected error %d", status);
143 desc->reslength = urb->actual_length;
144 memmove(desc->ubuf + desc->length, desc->inbuf, desc->reslength);
145 desc->length += desc->reslength;
146 wake_up(&desc->wait);
148 set_bit(WDM_READ, &desc->flags);
149 spin_unlock(&desc->iuspin);
152 static void wdm_int_callback(struct urb *urb)
155 int status = urb->status;
156 struct wdm_device *desc;
157 struct usb_ctrlrequest *req;
158 struct usb_cdc_notification *dr;
162 dr = (struct usb_cdc_notification *)desc->sbuf;
171 set_bit(WDM_INT_STALL, &desc->flags);
172 err("Stall on int endpoint");
173 goto sw; /* halt is cleared in work */
175 err("nonzero urb status received: %d", status);
180 if (urb->actual_length < sizeof(struct usb_cdc_notification)) {
181 err("wdm_int_callback - %d bytes", urb->actual_length);
185 switch (dr->bNotificationType) {
186 case USB_CDC_NOTIFY_RESPONSE_AVAILABLE:
187 dev_dbg(&desc->intf->dev,
188 "NOTIFY_RESPONSE_AVAILABLE received: index %d len %d",
189 dr->wIndex, dr->wLength);
192 case USB_CDC_NOTIFY_NETWORK_CONNECTION:
194 dev_dbg(&desc->intf->dev,
195 "NOTIFY_NETWORK_CONNECTION %s network",
196 dr->wValue ? "connected to" : "disconnected from");
199 clear_bit(WDM_POLL_RUNNING, &desc->flags);
200 err("unknown notification %d received: index %d len %d",
201 dr->bNotificationType, dr->wIndex, dr->wLength);
205 req->bRequestType = (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE);
206 req->bRequest = USB_CDC_GET_ENCAPSULATED_RESPONSE;
208 req->wIndex = desc->inum;
209 req->wLength = cpu_to_le16(desc->wMaxCommand);
211 usb_fill_control_urb(
213 interface_to_usbdev(desc->intf),
214 /* using common endpoint 0 */
215 usb_rcvctrlpipe(interface_to_usbdev(desc->intf), 0),
216 (unsigned char *)req,
222 desc->response->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
223 spin_lock(&desc->iuspin);
224 clear_bit(WDM_READ, &desc->flags);
225 if (!test_bit(WDM_DISCONNECTING, &desc->flags)) {
226 rv = usb_submit_urb(desc->response, GFP_ATOMIC);
227 dev_dbg(&desc->intf->dev, "%s: usb_submit_urb %d",
230 spin_unlock(&desc->iuspin);
236 rv = schedule_work(&desc->rxwork);
238 err("Cannot schedule work");
242 rv = usb_submit_urb(urb, GFP_ATOMIC);
244 err("%s - usb_submit_urb failed with result %d",
249 static void kill_urbs(struct wdm_device *desc)
251 usb_kill_urb(desc->command);
252 usb_kill_urb(desc->validity);
253 usb_kill_urb(desc->response);
256 static void free_urbs(struct wdm_device *desc)
258 usb_free_urb(desc->validity);
259 usb_free_urb(desc->response);
260 usb_free_urb(desc->command);
263 static void cleanup(struct wdm_device *desc)
265 usb_buffer_free(interface_to_usbdev(desc->intf),
266 desc->wMaxPacketSize,
268 desc->validity->transfer_dma);
269 usb_buffer_free(interface_to_usbdev(desc->intf),
272 desc->response->transfer_dma);
280 static ssize_t wdm_write
281 (struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
284 int rv = -EMSGSIZE, r, we;
285 struct wdm_device *desc = file->private_data;
286 struct usb_ctrlrequest *req;
288 if (count > desc->wMaxCommand)
289 count = desc->wMaxCommand;
291 spin_lock_irq(&desc->iuspin);
294 spin_unlock_irq(&desc->iuspin);
298 r = mutex_lock_interruptible(&desc->wlock); /* concurrent writes */
303 r = wait_event_interruptible(desc->wait, !test_bit(WDM_IN_USE,
308 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
313 desc->outbuf = buf = kmalloc(count, GFP_KERNEL);
319 r = copy_from_user(buf, buffer, count);
327 usb_fill_control_urb(
329 interface_to_usbdev(desc->intf),
330 /* using common endpoint 0 */
331 usb_sndctrlpipe(interface_to_usbdev(desc->intf), 0),
332 (unsigned char *)req,
339 req->bRequestType = (USB_DIR_OUT | USB_TYPE_CLASS |
340 USB_RECIP_INTERFACE);
341 req->bRequest = USB_CDC_SEND_ENCAPSULATED_COMMAND;
343 req->wIndex = desc->inum;
344 req->wLength = cpu_to_le16(count);
345 set_bit(WDM_IN_USE, &desc->flags);
347 rv = usb_submit_urb(desc->command, GFP_KERNEL);
350 clear_bit(WDM_IN_USE, &desc->flags);
351 err("Tx URB error: %d", rv);
353 dev_dbg(&desc->intf->dev, "Tx URB has been submitted index=%d",
357 mutex_unlock(&desc->wlock);
359 return rv < 0 ? rv : count;
362 static ssize_t wdm_read
363 (struct file *file, char __user *buffer, size_t count, loff_t *ppos)
367 struct wdm_device *desc = file->private_data;
370 rv = mutex_lock_interruptible(&desc->rlock); /*concurrent reads */
374 if (desc->length == 0) {
378 rv = wait_event_interruptible(desc->wait,
379 test_bit(WDM_READ, &desc->flags));
386 spin_lock_irq(&desc->iuspin);
388 if (desc->rerr) { /* read completed, error happened */
391 spin_unlock_irq(&desc->iuspin);
392 err("reading had resulted in %d", t);
397 * recheck whether we've lost the race
398 * against the completion handler
400 if (!test_bit(WDM_READ, &desc->flags)) { /* lost race */
401 spin_unlock_irq(&desc->iuspin);
404 if (!desc->reslength) { /* zero length read */
405 spin_unlock_irq(&desc->iuspin);
408 clear_bit(WDM_READ, &desc->flags);
409 spin_unlock_irq(&desc->iuspin);
412 cntr = count > desc->length ? desc->length : count;
413 rv = copy_to_user(buffer, desc->ubuf, cntr);
419 for (i = 0; i < desc->length - cntr; i++)
420 desc->ubuf[i] = desc->ubuf[i + cntr];
422 desc->length -= cntr;
423 /* in case we had outstanding data */
425 clear_bit(WDM_READ, &desc->flags);
429 mutex_unlock(&desc->rlock);
431 err("wdm_read: exit error");
435 static int wdm_flush(struct file *file, fl_owner_t id)
437 struct wdm_device *desc = file->private_data;
439 wait_event(desc->wait, !test_bit(WDM_IN_USE, &desc->flags));
441 err("Error in flush path: %d", desc->werr);
446 static unsigned int wdm_poll(struct file *file, struct poll_table_struct *wait)
448 struct wdm_device *desc = file->private_data;
450 unsigned int mask = 0;
452 spin_lock_irqsave(&desc->iuspin, flags);
453 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
455 spin_unlock_irqrestore(&desc->iuspin, flags);
458 if (test_bit(WDM_READ, &desc->flags))
459 mask = POLLIN | POLLRDNORM;
460 if (desc->rerr || desc->werr)
462 if (!test_bit(WDM_IN_USE, &desc->flags))
463 mask |= POLLOUT | POLLWRNORM;
464 spin_unlock_irqrestore(&desc->iuspin, flags);
466 poll_wait(file, &desc->wait, wait);
472 static int wdm_open(struct inode *inode, struct file *file)
474 int minor = iminor(inode);
476 struct usb_interface *intf;
477 struct wdm_device *desc;
479 mutex_lock(&wdm_mutex);
480 intf = usb_find_interface(&wdm_driver, minor);
484 desc = usb_get_intfdata(intf);
485 if (test_bit(WDM_DISCONNECTING, &desc->flags))
489 file->private_data = desc;
491 rv = usb_submit_urb(desc->validity, GFP_KERNEL);
495 err("Error submitting int urb - %d", rv);
501 mutex_unlock(&wdm_mutex);
505 static int wdm_release(struct inode *inode, struct file *file)
507 struct wdm_device *desc = file->private_data;
509 mutex_lock(&wdm_mutex);
512 dev_dbg(&desc->intf->dev, "wdm_release: cleanup");
515 mutex_unlock(&wdm_mutex);
519 static const struct file_operations wdm_fops = {
520 .owner = THIS_MODULE,
525 .release = wdm_release,
529 static struct usb_class_driver wdm_class = {
532 .minor_base = WDM_MINOR_BASE,
535 /* --- error handling --- */
536 static void wdm_rxwork(struct work_struct *work)
538 struct wdm_device *desc = container_of(work, struct wdm_device, rxwork);
542 spin_lock_irqsave(&desc->iuspin, flags);
543 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
544 spin_unlock_irqrestore(&desc->iuspin, flags);
546 spin_unlock_irqrestore(&desc->iuspin, flags);
547 rv = usb_submit_urb(desc->response, GFP_KERNEL);
548 if (rv < 0 && rv != -EPERM) {
549 spin_lock_irqsave(&desc->iuspin, flags);
550 if (!test_bit(WDM_DISCONNECTING, &desc->flags))
551 schedule_work(&desc->rxwork);
552 spin_unlock_irqrestore(&desc->iuspin, flags);
557 /* --- hotplug --- */
559 static int wdm_probe(struct usb_interface *intf, const struct usb_device_id *id)
562 struct usb_device *udev = interface_to_usbdev(intf);
563 struct wdm_device *desc;
564 struct usb_host_interface *iface;
565 struct usb_endpoint_descriptor *ep;
566 struct usb_cdc_dmm_desc *dmhd;
567 u8 *buffer = intf->altsetting->extra;
568 int buflen = intf->altsetting->extralen;
575 if (buffer [1] != USB_DT_CS_INTERFACE) {
576 err("skipping garbage");
580 switch (buffer [2]) {
581 case USB_CDC_HEADER_TYPE:
583 case USB_CDC_DMM_TYPE:
584 dmhd = (struct usb_cdc_dmm_desc *)buffer;
585 maxcom = le16_to_cpu(dmhd->wMaxCommand);
587 "Finding maximum buffer length: %d", maxcom);
590 err("Ignoring extra header, type %d, length %d",
591 buffer[2], buffer[0]);
600 desc = kzalloc(sizeof(struct wdm_device), GFP_KERNEL);
603 mutex_init(&desc->wlock);
604 mutex_init(&desc->rlock);
605 spin_lock_init(&desc->iuspin);
606 init_waitqueue_head(&desc->wait);
607 desc->wMaxCommand = maxcom;
608 desc->inum = cpu_to_le16((u16)intf->cur_altsetting->desc.bInterfaceNumber);
610 INIT_WORK(&desc->rxwork, wdm_rxwork);
612 iface = &intf->altsetting[0];
613 ep = &iface->endpoint[0].desc;
614 if (!usb_endpoint_is_int_in(ep)) {
619 desc->wMaxPacketSize = le16_to_cpu(ep->wMaxPacketSize);
620 desc->bMaxPacketSize0 = udev->descriptor.bMaxPacketSize0;
622 desc->orq = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
625 desc->irq = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
629 desc->validity = usb_alloc_urb(0, GFP_KERNEL);
633 desc->response = usb_alloc_urb(0, GFP_KERNEL);
637 desc->command = usb_alloc_urb(0, GFP_KERNEL);
641 desc->ubuf = kmalloc(desc->wMaxCommand, GFP_KERNEL);
645 desc->sbuf = usb_buffer_alloc(interface_to_usbdev(intf),
646 desc->wMaxPacketSize,
648 &desc->validity->transfer_dma);
652 desc->inbuf = usb_buffer_alloc(interface_to_usbdev(intf),
653 desc->bMaxPacketSize0,
655 &desc->response->transfer_dma);
661 interface_to_usbdev(intf),
662 usb_rcvintpipe(interface_to_usbdev(intf), ep->bEndpointAddress),
664 desc->wMaxPacketSize,
669 desc->validity->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
671 usb_set_intfdata(intf, desc);
672 rv = usb_register_dev(intf, &wdm_class);
673 dev_info(&intf->dev, "cdc-wdm%d: USB WDM device\n",
674 intf->minor - WDM_MINOR_BASE);
680 usb_buffer_free(interface_to_usbdev(desc->intf),
681 desc->wMaxPacketSize,
683 desc->validity->transfer_dma);
693 static void wdm_disconnect(struct usb_interface *intf)
695 struct wdm_device *desc;
698 usb_deregister_dev(intf, &wdm_class);
699 mutex_lock(&wdm_mutex);
700 desc = usb_get_intfdata(intf);
702 /* the spinlock makes sure no new urbs are generated in the callbacks */
703 spin_lock_irqsave(&desc->iuspin, flags);
704 set_bit(WDM_DISCONNECTING, &desc->flags);
705 set_bit(WDM_READ, &desc->flags);
706 clear_bit(WDM_IN_USE, &desc->flags);
707 spin_unlock_irqrestore(&desc->iuspin, flags);
708 cancel_work_sync(&desc->rxwork);
710 wake_up_all(&desc->wait);
713 mutex_unlock(&wdm_mutex);
716 static struct usb_driver wdm_driver = {
719 .disconnect = wdm_disconnect,
723 /* --- low level module stuff --- */
725 static int __init wdm_init(void)
729 rv = usb_register(&wdm_driver);
734 static void __exit wdm_exit(void)
736 usb_deregister(&wdm_driver);
739 module_init(wdm_init);
740 module_exit(wdm_exit);
742 MODULE_AUTHOR(DRIVER_AUTHOR);
743 MODULE_DESCRIPTION(DRIVER_DESC);
744 MODULE_LICENSE("GPL");