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USB: cdc-wdm cleanup
[linux-2.6/mini2440.git] / drivers / usb / class / cdc-wdm.c
blob3a656f8f99357247ccf164ac3a42ce407d92d729
1 /*
2 * cdc-wdm.c
3 *
4 * This driver supports USB CDC WCM Device Management.
5 *
6 * Copyright (c) 2007-2008 Oliver Neukum
7 *
8 * Some code taken from cdc-acm.c
9 *
10 * Released under the GPLv2.
11 *
12 * Many thanks to Carl Nordbeck
13 */
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>
27
28 /*
29 * Version Information
30 */
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"
34
35 static struct usb_device_id wdm_ids[] = {
36 {
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
41 },
42 { }
43 };
44
45 #define WDM_MINOR_BASE 176
46
47
48 #define WDM_IN_USE 1
49 #define WDM_DISCONNECTING 2
50 #define WDM_RESULT 3
51 #define WDM_READ 4
52 #define WDM_INT_STALL 5
53 #define WDM_POLL_RUNNING 6
54
55
56 #define WDM_MAX 16
57
58
59 static DEFINE_MUTEX(wdm_mutex);
60
61 /* --- method tables --- */
62
63 struct wdm_device {
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 */
68
69 struct urb *command;
70 struct urb *response;
71 struct urb *validity;
72 struct usb_interface *intf;
73 struct usb_ctrlrequest *orq;
74 struct usb_ctrlrequest *irq;
75 spinlock_t iuspin;
76
77 unsigned long flags;
78 u16 bufsize;
79 u16 wMaxCommand;
80 u16 wMaxPacketSize;
81 u16 bMaxPacketSize0;
82 __le16 inum;
83 int reslength;
84 int length;
85 int read;
86 int count;
87 dma_addr_t shandle;
88 dma_addr_t ihandle;
89 struct mutex wlock;
90 struct mutex rlock;
91 wait_queue_head_t wait;
92 struct work_struct rxwork;
93 int werr;
94 int rerr;
95 };
96
97 static struct usb_driver wdm_driver;
98
99 /* --- callbacks --- */
100 static void wdm_out_callback(struct urb *urb)
101 {
102 struct wdm_device *desc;
103 desc = urb->context;
104 spin_lock(&desc->iuspin);
105 desc->werr = urb->status;
106 spin_unlock(&desc->iuspin);
107 clear_bit(WDM_IN_USE, &desc->flags);
108 kfree(desc->outbuf);
109 wake_up(&desc->wait);
110 }
111
112 static void wdm_in_callback(struct urb *urb)
113 {
114 struct wdm_device *desc = urb->context;
115 int status = urb->status;
116
117 spin_lock(&desc->iuspin);
118
119 if (status) {
120 switch (status) {
121 case -ENOENT:
122 dev_dbg(&desc->intf->dev,
123 "nonzero urb status received: -ENOENT");
124 break;
125 case -ECONNRESET:
126 dev_dbg(&desc->intf->dev,
127 "nonzero urb status received: -ECONNRESET");
128 break;
129 case -ESHUTDOWN:
130 dev_dbg(&desc->intf->dev,
131 "nonzero urb status received: -ESHUTDOWN");
132 break;
133 case -EPIPE:
134 err("nonzero urb status received: -EPIPE");
135 break;
136 default:
137 err("Unexpected error %d", status);
138 break;
139 }
140 }
141
142 desc->rerr = 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);
147
148 set_bit(WDM_READ, &desc->flags);
149 spin_unlock(&desc->iuspin);
150 }
151
152 static void wdm_int_callback(struct urb *urb)
153 {
154 int rv = 0;
155 int status = urb->status;
156 struct wdm_device *desc;
157 struct usb_ctrlrequest *req;
158 struct usb_cdc_notification *dr;
159
160 desc = urb->context;
161 req = desc->irq;
162 dr = (struct usb_cdc_notification *)desc->sbuf;
163
164 if (status) {
165 switch (status) {
166 case -ESHUTDOWN:
167 case -ENOENT:
168 case -ECONNRESET:
169 return; /* unplug */
170 case -EPIPE:
171 set_bit(WDM_INT_STALL, &desc->flags);
172 err("Stall on int endpoint");
173 goto sw; /* halt is cleared in work */
174 default:
175 err("nonzero urb status received: %d", status);
176 break;
177 }
178 }
179
180 if (urb->actual_length < sizeof(struct usb_cdc_notification)) {
181 err("wdm_int_callback - %d bytes", urb->actual_length);
182 goto exit;
183 }
184
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);
190 break;
191
192 case USB_CDC_NOTIFY_NETWORK_CONNECTION:
193
194 dev_dbg(&desc->intf->dev,
195 "NOTIFY_NETWORK_CONNECTION %s network",
196 dr->wValue ? "connected to" : "disconnected from");
197 goto exit;
198 default:
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);
202 goto exit;
203 }
204
205 req->bRequestType = (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE);
206 req->bRequest = USB_CDC_GET_ENCAPSULATED_RESPONSE;
207 req->wValue = 0;
208 req->wIndex = desc->inum;
209 req->wLength = cpu_to_le16(desc->wMaxCommand);
210
211 usb_fill_control_urb(
212 desc->response,
213 interface_to_usbdev(desc->intf),
214 /* using common endpoint 0 */
215 usb_rcvctrlpipe(interface_to_usbdev(desc->intf), 0),
216 (unsigned char *)req,
217 desc->inbuf,
218 desc->wMaxCommand,
219 wdm_in_callback,
220 desc
221 );
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",
228 __func__, rv);
229 }
230 spin_unlock(&desc->iuspin);
231 if (rv < 0) {
232 if (rv == -EPERM)
233 return;
234 if (rv == -ENOMEM) {
235 sw:
236 rv = schedule_work(&desc->rxwork);
237 if (rv)
238 err("Cannot schedule work");
239 }
240 }
241 exit:
242 rv = usb_submit_urb(urb, GFP_ATOMIC);
243 if (rv)
244 err("%s - usb_submit_urb failed with result %d",
245 __func__, rv);
246
247 }
248
249 static void kill_urbs(struct wdm_device *desc)
250 {
251 usb_kill_urb(desc->command);
252 usb_kill_urb(desc->validity);
253 usb_kill_urb(desc->response);
254 }
255
256 static void free_urbs(struct wdm_device *desc)
257 {
258 usb_free_urb(desc->validity);
259 usb_free_urb(desc->response);
260 usb_free_urb(desc->command);
261 }
262
263 static void cleanup(struct wdm_device *desc)
264 {
265 usb_buffer_free(interface_to_usbdev(desc->intf),
266 desc->wMaxPacketSize,
267 desc->sbuf,
268 desc->validity->transfer_dma);
269 usb_buffer_free(interface_to_usbdev(desc->intf),
270 desc->wMaxCommand,
271 desc->inbuf,
272 desc->response->transfer_dma);
273 kfree(desc->orq);
274 kfree(desc->irq);
275 kfree(desc->ubuf);
276 free_urbs(desc);
277 kfree(desc);
278 }
279
280 static ssize_t wdm_write
281 (struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
282 {
283 u8 *buf;
284 int rv = -EMSGSIZE, r, we;
285 struct wdm_device *desc = file->private_data;
286 struct usb_ctrlrequest *req;
287
288 if (count > desc->wMaxCommand)
289 count = desc->wMaxCommand;
290
291 spin_lock_irq(&desc->iuspin);
292 we = desc->werr;
293 desc->werr = 0;
294 spin_unlock_irq(&desc->iuspin);
295 if (we < 0)
296 return -EIO;
297
298 r = mutex_lock_interruptible(&desc->wlock); /* concurrent writes */
299 rv = -ERESTARTSYS;
300 if (r)
301 goto outnl;
302
303 r = wait_event_interruptible(desc->wait, !test_bit(WDM_IN_USE,
304 &desc->flags));
305 if (r < 0)
306 goto out;
307
308 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
309 rv = -ENODEV;
310 goto out;
311 }
312
313 desc->outbuf = buf = kmalloc(count, GFP_KERNEL);
314 if (!buf) {
315 rv = -ENOMEM;
316 goto out;
317 }
318
319 r = copy_from_user(buf, buffer, count);
320 if (r > 0) {
321 kfree(buf);
322 rv = -EFAULT;
323 goto out;
324 }
325
326 req = desc->orq;
327 usb_fill_control_urb(
328 desc->command,
329 interface_to_usbdev(desc->intf),
330 /* using common endpoint 0 */
331 usb_sndctrlpipe(interface_to_usbdev(desc->intf), 0),
332 (unsigned char *)req,
333 buf,
334 count,
335 wdm_out_callback,
336 desc
337 );
338
339 req->bRequestType = (USB_DIR_OUT | USB_TYPE_CLASS |
340 USB_RECIP_INTERFACE);
341 req->bRequest = USB_CDC_SEND_ENCAPSULATED_COMMAND;
342 req->wValue = 0;
343 req->wIndex = desc->inum;
344 req->wLength = cpu_to_le16(count);
345 set_bit(WDM_IN_USE, &desc->flags);
346
347 rv = usb_submit_urb(desc->command, GFP_KERNEL);
348 if (rv < 0) {
349 kfree(buf);
350 clear_bit(WDM_IN_USE, &desc->flags);
351 err("Tx URB error: %d", rv);
352 } else {
353 dev_dbg(&desc->intf->dev, "Tx URB has been submitted index=%d",
354 req->wIndex);
355 }
356 out:
357 mutex_unlock(&desc->wlock);
358 outnl:
359 return rv < 0 ? rv : count;
360 }
361
362 static ssize_t wdm_read
363 (struct file *file, char __user *buffer, size_t count, loff_t *ppos)
364 {
365 int rv, cntr;
366 int i = 0;
367 struct wdm_device *desc = file->private_data;
368
369
370 rv = mutex_lock_interruptible(&desc->rlock); /*concurrent reads */
371 if (rv < 0)
372 return -ERESTARTSYS;
373
374 if (desc->length == 0) {
375 desc->read = 0;
376 retry:
377 i++;
378 rv = wait_event_interruptible(desc->wait,
379 test_bit(WDM_READ, &desc->flags));
380
381 if (rv < 0) {
382 rv = -ERESTARTSYS;
383 goto err;
384 }
385
386 spin_lock_irq(&desc->iuspin);
387
388 if (desc->rerr) { /* read completed, error happened */
389 int t = desc->rerr;
390 desc->rerr = 0;
391 spin_unlock_irq(&desc->iuspin);
392 err("reading had resulted in %d", t);
393 rv = -EIO;
394 goto err;
395 }
396 /*
397 * recheck whether we've lost the race
398 * against the completion handler
399 */
400 if (!test_bit(WDM_READ, &desc->flags)) { /* lost race */
401 spin_unlock_irq(&desc->iuspin);
402 goto retry;
403 }
404 if (!desc->reslength) { /* zero length read */
405 spin_unlock_irq(&desc->iuspin);
406 goto retry;
407 }
408 clear_bit(WDM_READ, &desc->flags);
409 spin_unlock_irq(&desc->iuspin);
410 }
411
412 cntr = count > desc->length ? desc->length : count;
413 rv = copy_to_user(buffer, desc->ubuf, cntr);
414 if (rv > 0) {
415 rv = -EFAULT;
416 goto err;
417 }
418
419 for (i = 0; i < desc->length - cntr; i++)
420 desc->ubuf[i] = desc->ubuf[i + cntr];
421
422 desc->length -= cntr;
423 /* in case we had outstanding data */
424 if (!desc->length)
425 clear_bit(WDM_READ, &desc->flags);
426 rv = cntr;
427
428 err:
429 mutex_unlock(&desc->rlock);
430 if (rv < 0)
431 err("wdm_read: exit error");
432 return rv;
433 }
434
435 static int wdm_flush(struct file *file, fl_owner_t id)
436 {
437 struct wdm_device *desc = file->private_data;
438
439 wait_event(desc->wait, !test_bit(WDM_IN_USE, &desc->flags));
440 if (desc->werr < 0)
441 err("Error in flush path: %d", desc->werr);
442
443 return desc->werr;
444 }
445
446 static unsigned int wdm_poll(struct file *file, struct poll_table_struct *wait)
447 {
448 struct wdm_device *desc = file->private_data;
449 unsigned long flags;
450 unsigned int mask = 0;
451
452 spin_lock_irqsave(&desc->iuspin, flags);
453 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
454 mask = POLLERR;
455 spin_unlock_irqrestore(&desc->iuspin, flags);
456 goto desc_out;
457 }
458 if (test_bit(WDM_READ, &desc->flags))
459 mask = POLLIN | POLLRDNORM;
460 if (desc->rerr || desc->werr)
461 mask |= POLLERR;
462 if (!test_bit(WDM_IN_USE, &desc->flags))
463 mask |= POLLOUT | POLLWRNORM;
464 spin_unlock_irqrestore(&desc->iuspin, flags);
465
466 poll_wait(file, &desc->wait, wait);
467
468 desc_out:
469 return mask;
470 }
471
472 static int wdm_open(struct inode *inode, struct file *file)
473 {
474 int minor = iminor(inode);
475 int rv = -ENODEV;
476 struct usb_interface *intf;
477 struct wdm_device *desc;
478
479 mutex_lock(&wdm_mutex);
480 intf = usb_find_interface(&wdm_driver, minor);
481 if (!intf)
482 goto out;
483
484 desc = usb_get_intfdata(intf);
485 if (test_bit(WDM_DISCONNECTING, &desc->flags))
486 goto out;
487
488 desc->count++;
489 file->private_data = desc;
490
491 rv = usb_submit_urb(desc->validity, GFP_KERNEL);
492
493 if (rv < 0) {
494 desc->count--;
495 err("Error submitting int urb - %d", rv);
496 goto out;
497 }
498 rv = 0;
499
500 out:
501 mutex_unlock(&wdm_mutex);
502 return rv;
503 }
504
505 static int wdm_release(struct inode *inode, struct file *file)
506 {
507 struct wdm_device *desc = file->private_data;
508
509 mutex_lock(&wdm_mutex);
510 desc->count--;
511 if (!desc->count) {
512 dev_dbg(&desc->intf->dev, "wdm_release: cleanup");
513 kill_urbs(desc);
514 }
515 mutex_unlock(&wdm_mutex);
516 return 0;
517 }
518
519 static const struct file_operations wdm_fops = {
520 .owner = THIS_MODULE,
521 .read = wdm_read,
522 .write = wdm_write,
523 .open = wdm_open,
524 .flush = wdm_flush,
525 .release = wdm_release,
526 .poll = wdm_poll
527 };
528
529 static struct usb_class_driver wdm_class = {
530 .name = "cdc-wdm%d",
531 .fops = &wdm_fops,
532 .minor_base = WDM_MINOR_BASE,
533 };
534
535 /* --- error handling --- */
536 static void wdm_rxwork(struct work_struct *work)
537 {
538 struct wdm_device *desc = container_of(work, struct wdm_device, rxwork);
539 unsigned long flags;
540 int rv;
541
542 spin_lock_irqsave(&desc->iuspin, flags);
543 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
544 spin_unlock_irqrestore(&desc->iuspin, flags);
545 } else {
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);
553 }
554 }
555 }
556
557 /* --- hotplug --- */
558
559 static int wdm_probe(struct usb_interface *intf, const struct usb_device_id *id)
560 {
561 int rv = -EINVAL;
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;
569 u16 maxcom = 0;
570
571 if (!buffer)
572 goto out;
573
574 while (buflen > 0) {
575 if (buffer [1] != USB_DT_CS_INTERFACE) {
576 err("skipping garbage");
577 goto next_desc;
578 }
579
580 switch (buffer [2]) {
581 case USB_CDC_HEADER_TYPE:
582 break;
583 case USB_CDC_DMM_TYPE:
584 dmhd = (struct usb_cdc_dmm_desc *)buffer;
585 maxcom = le16_to_cpu(dmhd->wMaxCommand);
586 dev_dbg(&intf->dev,
587 "Finding maximum buffer length: %d", maxcom);
588 break;
589 default:
590 err("Ignoring extra header, type %d, length %d",
591 buffer[2], buffer[0]);
592 break;
593 }
594 next_desc:
595 buflen -= buffer[0];
596 buffer += buffer[0];
597 }
598
599 rv = -ENOMEM;
600 desc = kzalloc(sizeof(struct wdm_device), GFP_KERNEL);
601 if (!desc)
602 goto out;
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);
609 desc->intf = intf;
610 INIT_WORK(&desc->rxwork, wdm_rxwork);
611
612 iface = &intf->altsetting[0];
613 ep = &iface->endpoint[0].desc;
614 if (!usb_endpoint_is_int_in(ep)) {
615 rv = -EINVAL;
616 goto err;
617 }
618
619 desc->wMaxPacketSize = le16_to_cpu(ep->wMaxPacketSize);
620 desc->bMaxPacketSize0 = udev->descriptor.bMaxPacketSize0;
621
622 desc->orq = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
623 if (!desc->orq)
624 goto err;
625 desc->irq = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
626 if (!desc->irq)
627 goto err;
628
629 desc->validity = usb_alloc_urb(0, GFP_KERNEL);
630 if (!desc->validity)
631 goto err;
632
633 desc->response = usb_alloc_urb(0, GFP_KERNEL);
634 if (!desc->response)
635 goto err;
636
637 desc->command = usb_alloc_urb(0, GFP_KERNEL);
638 if (!desc->command)
639 goto err;
640
641 desc->ubuf = kmalloc(desc->wMaxCommand, GFP_KERNEL);
642 if (!desc->ubuf)
643 goto err;
644
645 desc->sbuf = usb_buffer_alloc(interface_to_usbdev(intf),
646 desc->wMaxPacketSize,
647 GFP_KERNEL,
648 &desc->validity->transfer_dma);
649 if (!desc->sbuf)
650 goto err;
651
652 desc->inbuf = usb_buffer_alloc(interface_to_usbdev(intf),
653 desc->bMaxPacketSize0,
654 GFP_KERNEL,
655 &desc->response->transfer_dma);
656 if (!desc->inbuf)
657 goto err2;
658
659 usb_fill_int_urb(
660 desc->validity,
661 interface_to_usbdev(intf),
662 usb_rcvintpipe(interface_to_usbdev(intf), ep->bEndpointAddress),
663 desc->sbuf,
664 desc->wMaxPacketSize,
665 wdm_int_callback,
666 desc,
667 ep->bInterval
668 );
669 desc->validity->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
670
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);
675 if (rv < 0)
676 goto err;
677 out:
678 return rv;
679 err2:
680 usb_buffer_free(interface_to_usbdev(desc->intf),
681 desc->wMaxPacketSize,
682 desc->sbuf,
683 desc->validity->transfer_dma);
684 err:
685 free_urbs(desc);
686 kfree(desc->ubuf);
687 kfree(desc->orq);
688 kfree(desc->irq);
689 kfree(desc);
690 return rv;
691 }
692
693 static void wdm_disconnect(struct usb_interface *intf)
694 {
695 struct wdm_device *desc;
696 unsigned long flags;
697
698 usb_deregister_dev(intf, &wdm_class);
699 mutex_lock(&wdm_mutex);
700 desc = usb_get_intfdata(intf);
701
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);
709 kill_urbs(desc);
710 wake_up_all(&desc->wait);
711 if (!desc->count)
712 cleanup(desc);
713 mutex_unlock(&wdm_mutex);
714 }
715
716 static struct usb_driver wdm_driver = {
717 .name = "cdc_wdm",
718 .probe = wdm_probe,
719 .disconnect = wdm_disconnect,
720 .id_table = wdm_ids,
721 };
722
723 /* --- low level module stuff --- */
724
725 static int __init wdm_init(void)
726 {
727 int rv;
728
729 rv = usb_register(&wdm_driver);
730
731 return rv;
732 }
733
734 static void __exit wdm_exit(void)
735 {
736 usb_deregister(&wdm_driver);
737 }
738
739 module_init(wdm_init);
740 module_exit(wdm_exit);
741
742 MODULE_AUTHOR(DRIVER_AUTHOR);
743 MODULE_DESCRIPTION(DRIVER_DESC);
744 MODULE_LICENSE("GPL");
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