USB: yurex: Remove allocation of coherent buffer for setup-packet buffer
[pandora-kernel.git] / drivers / usb / misc / yurex.c
1 /*
2  * Driver for Meywa-Denki & KAYAC YUREX
3  *
4  * Copyright (C) 2010 Tomoki Sekiyama (tomoki.sekiyama@gmail.com)
5  *
6  *      This program is free software; you can redistribute it and/or
7  *      modify it under the terms of the GNU General Public License as
8  *      published by the Free Software Foundation, version 2.
9  *
10  */
11
12 #include <linux/kernel.h>
13 #include <linux/errno.h>
14 #include <linux/init.h>
15 #include <linux/slab.h>
16 #include <linux/module.h>
17 #include <linux/kref.h>
18 #include <linux/mutex.h>
19 #include <linux/uaccess.h>
20 #include <linux/usb.h>
21 #include <linux/hid.h>
22
23 #define DRIVER_AUTHOR "Tomoki Sekiyama"
24 #define DRIVER_DESC "Driver for Meywa-Denki & KAYAC YUREX"
25
26 #define YUREX_VENDOR_ID         0x0c45
27 #define YUREX_PRODUCT_ID        0x1010
28
29 #define CMD_ACK         '!'
30 #define CMD_ANIMATE     'A'
31 #define CMD_COUNT       'C'
32 #define CMD_LED         'L'
33 #define CMD_READ        'R'
34 #define CMD_SET         'S'
35 #define CMD_VERSION     'V'
36 #define CMD_EOF         0x0d
37 #define CMD_PADDING     0xff
38
39 #define YUREX_BUF_SIZE          8
40 #define YUREX_WRITE_TIMEOUT     (HZ*2)
41
42 /* table of devices that work with this driver */
43 static struct usb_device_id yurex_table[] = {
44         { USB_DEVICE(YUREX_VENDOR_ID, YUREX_PRODUCT_ID) },
45         { }                                     /* Terminating entry */
46 };
47 MODULE_DEVICE_TABLE(usb, yurex_table);
48
49 #ifdef CONFIG_USB_DYNAMIC_MINORS
50 #define YUREX_MINOR_BASE        0
51 #else
52 #define YUREX_MINOR_BASE        192
53 #endif
54
55 /* Structure to hold all of our device specific stuff */
56 struct usb_yurex {
57         struct usb_device       *udev;
58         struct usb_interface    *interface;
59         __u8                    int_in_endpointAddr;
60         struct urb              *urb;           /* URB for interrupt in */
61         unsigned char           *int_buffer;    /* buffer for intterupt in */
62         struct urb              *cntl_urb;      /* URB for control msg */
63         struct usb_ctrlrequest  *cntl_req;      /* req for control msg */
64         unsigned char           *cntl_buffer;   /* buffer for control msg */
65
66         struct kref             kref;
67         struct mutex            io_mutex;
68         struct fasync_struct    *async_queue;
69         wait_queue_head_t       waitq;
70
71         spinlock_t              lock;
72         __s64                   bbu;            /* BBU from device */
73 };
74 #define to_yurex_dev(d) container_of(d, struct usb_yurex, kref)
75
76 static struct usb_driver yurex_driver;
77 static const struct file_operations yurex_fops;
78
79
80 static void yurex_control_callback(struct urb *urb)
81 {
82         struct usb_yurex *dev = urb->context;
83         int status = urb->status;
84
85         if (status) {
86                 err("%s - control failed: %d\n", __func__, status);
87                 wake_up_interruptible(&dev->waitq);
88                 return;
89         }
90         /* on success, sender woken up by CMD_ACK int in, or timeout */
91 }
92
93 static void yurex_delete(struct kref *kref)
94 {
95         struct usb_yurex *dev = to_yurex_dev(kref);
96
97         dbg("yurex_delete");
98
99         usb_put_dev(dev->udev);
100         if (dev->cntl_urb) {
101                 usb_kill_urb(dev->cntl_urb);
102                 kfree(dev->cntl_req);
103                 if (dev->cntl_buffer)
104                         usb_free_coherent(dev->udev, YUREX_BUF_SIZE,
105                                 dev->cntl_buffer, dev->cntl_urb->transfer_dma);
106                 usb_free_urb(dev->cntl_urb);
107         }
108         if (dev->urb) {
109                 usb_kill_urb(dev->urb);
110                 if (dev->int_buffer)
111                         usb_free_coherent(dev->udev, YUREX_BUF_SIZE,
112                                 dev->int_buffer, dev->urb->transfer_dma);
113                 usb_free_urb(dev->urb);
114         }
115         kfree(dev);
116 }
117
118 /*
119  * usb class driver info in order to get a minor number from the usb core,
120  * and to have the device registered with the driver core
121  */
122 static struct usb_class_driver yurex_class = {
123         .name =         "yurex%d",
124         .fops =         &yurex_fops,
125         .minor_base =   YUREX_MINOR_BASE,
126 };
127
128 static void yurex_interrupt(struct urb *urb)
129 {
130         struct usb_yurex *dev = urb->context;
131         unsigned char *buf = dev->int_buffer;
132         int status = urb->status;
133         unsigned long flags;
134         int retval, i;
135
136         switch (status) {
137         case 0: /*success*/
138                 break;
139         case -EOVERFLOW:
140                 err("%s - overflow with length %d, actual length is %d",
141                     __func__, YUREX_BUF_SIZE, dev->urb->actual_length);
142         case -ECONNRESET:
143         case -ENOENT:
144         case -ESHUTDOWN:
145         case -EILSEQ:
146                 /* The device is terminated, clean up */
147                 return;
148         default:
149                 err("%s - unknown status received: %d", __func__, status);
150                 goto exit;
151         }
152
153         /* handle received message */
154         switch (buf[0]) {
155         case CMD_COUNT:
156         case CMD_READ:
157                 if (buf[6] == CMD_EOF) {
158                         spin_lock_irqsave(&dev->lock, flags);
159                         dev->bbu = 0;
160                         for (i = 1; i < 6; i++) {
161                                 dev->bbu += buf[i];
162                                 if (i != 5)
163                                         dev->bbu <<= 8;
164                         }
165                         dbg("%s count: %lld", __func__, dev->bbu);
166                         spin_unlock_irqrestore(&dev->lock, flags);
167
168                         kill_fasync(&dev->async_queue, SIGIO, POLL_IN);
169                 }
170                 else
171                         dbg("data format error - no EOF");
172                 break;
173         case CMD_ACK:
174                 dbg("%s ack: %c", __func__, buf[1]);
175                 wake_up_interruptible(&dev->waitq);
176                 break;
177         }
178
179 exit:
180         retval = usb_submit_urb(dev->urb, GFP_ATOMIC);
181         if (retval) {
182                 err("%s - usb_submit_urb failed: %d",
183                         __func__, retval);
184         }
185 }
186
187 static int yurex_probe(struct usb_interface *interface, const struct usb_device_id *id)
188 {
189         struct usb_yurex *dev;
190         struct usb_host_interface *iface_desc;
191         struct usb_endpoint_descriptor *endpoint;
192         int retval = -ENOMEM;
193         int i;
194         DEFINE_WAIT(wait);
195
196         /* allocate memory for our device state and initialize it */
197         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
198         if (!dev) {
199                 err("Out of memory");
200                 goto error;
201         }
202         kref_init(&dev->kref);
203         mutex_init(&dev->io_mutex);
204         spin_lock_init(&dev->lock);
205         init_waitqueue_head(&dev->waitq);
206
207         dev->udev = usb_get_dev(interface_to_usbdev(interface));
208         dev->interface = interface;
209
210         /* set up the endpoint information */
211         iface_desc = interface->cur_altsetting;
212         for (i = 0; i < iface_desc->desc.bNumEndpoints; i++) {
213                 endpoint = &iface_desc->endpoint[i].desc;
214
215                 if (usb_endpoint_is_int_in(endpoint)) {
216                         dev->int_in_endpointAddr = endpoint->bEndpointAddress;
217                         break;
218                 }
219         }
220         if (!dev->int_in_endpointAddr) {
221                 retval = -ENODEV;
222                 err("Could not find endpoints");
223                 goto error;
224         }
225
226
227         /* allocate control URB */
228         dev->cntl_urb = usb_alloc_urb(0, GFP_KERNEL);
229         if (!dev->cntl_urb) {
230                 err("Could not allocate control URB");
231                 goto error;
232         }
233
234         /* allocate buffer for control req */
235         dev->cntl_req = kmalloc(YUREX_BUF_SIZE, GFP_KERNEL);
236         if (!dev->cntl_req) {
237                 err("Could not allocate cntl_req");
238                 goto error;
239         }
240
241         /* allocate buffer for control msg */
242         dev->cntl_buffer = usb_alloc_coherent(dev->udev, YUREX_BUF_SIZE,
243                                               GFP_KERNEL,
244                                               &dev->cntl_urb->transfer_dma);
245         if (!dev->cntl_buffer) {
246                 err("Could not allocate cntl_buffer");
247                 goto error;
248         }
249
250         /* configure control URB */
251         dev->cntl_req->bRequestType = USB_DIR_OUT | USB_TYPE_CLASS |
252                                       USB_RECIP_INTERFACE;
253         dev->cntl_req->bRequest = HID_REQ_SET_REPORT;
254         dev->cntl_req->wValue   = cpu_to_le16((HID_OUTPUT_REPORT + 1) << 8);
255         dev->cntl_req->wIndex   = cpu_to_le16(iface_desc->desc.bInterfaceNumber);
256         dev->cntl_req->wLength  = cpu_to_le16(YUREX_BUF_SIZE);
257
258         usb_fill_control_urb(dev->cntl_urb, dev->udev,
259                              usb_sndctrlpipe(dev->udev, 0),
260                              (void *)dev->cntl_req, dev->cntl_buffer,
261                              YUREX_BUF_SIZE, yurex_control_callback, dev);
262         dev->cntl_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
263
264
265         /* allocate interrupt URB */
266         dev->urb = usb_alloc_urb(0, GFP_KERNEL);
267         if (!dev->urb) {
268                 err("Could not allocate URB");
269                 goto error;
270         }
271
272         /* allocate buffer for interrupt in */
273         dev->int_buffer = usb_alloc_coherent(dev->udev, YUREX_BUF_SIZE,
274                                         GFP_KERNEL, &dev->urb->transfer_dma);
275         if (!dev->int_buffer) {
276                 err("Could not allocate int_buffer");
277                 goto error;
278         }
279
280         /* configure interrupt URB */
281         usb_fill_int_urb(dev->urb, dev->udev,
282                          usb_rcvintpipe(dev->udev, dev->int_in_endpointAddr),
283                          dev->int_buffer, YUREX_BUF_SIZE, yurex_interrupt,
284                          dev, 1);
285         dev->cntl_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
286         if (usb_submit_urb(dev->urb, GFP_KERNEL)) {
287                 retval = -EIO;
288                 err("Could not submitting URB");
289                 goto error;
290         }
291
292         /* save our data pointer in this interface device */
293         usb_set_intfdata(interface, dev);
294
295         /* we can register the device now, as it is ready */
296         retval = usb_register_dev(interface, &yurex_class);
297         if (retval) {
298                 err("Not able to get a minor for this device.");
299                 usb_set_intfdata(interface, NULL);
300                 goto error;
301         }
302
303         dev->bbu = -1;
304
305         dev_info(&interface->dev,
306                  "USB YUREX device now attached to Yurex #%d\n",
307                  interface->minor);
308
309         return 0;
310
311 error:
312         if (dev)
313                 /* this frees allocated memory */
314                 kref_put(&dev->kref, yurex_delete);
315         return retval;
316 }
317
318 static void yurex_disconnect(struct usb_interface *interface)
319 {
320         struct usb_yurex *dev;
321         int minor = interface->minor;
322
323         dev = usb_get_intfdata(interface);
324         usb_set_intfdata(interface, NULL);
325
326         /* give back our minor */
327         usb_deregister_dev(interface, &yurex_class);
328
329         /* prevent more I/O from starting */
330         mutex_lock(&dev->io_mutex);
331         dev->interface = NULL;
332         mutex_unlock(&dev->io_mutex);
333
334         /* wakeup waiters */
335         kill_fasync(&dev->async_queue, SIGIO, POLL_IN);
336         wake_up_interruptible(&dev->waitq);
337
338         /* decrement our usage count */
339         kref_put(&dev->kref, yurex_delete);
340
341         dev_info(&interface->dev, "USB YUREX #%d now disconnected\n", minor);
342 }
343
344 static struct usb_driver yurex_driver = {
345         .name =         "yurex",
346         .probe =        yurex_probe,
347         .disconnect =   yurex_disconnect,
348         .id_table =     yurex_table,
349 };
350
351
352 static int yurex_fasync(int fd, struct file *file, int on)
353 {
354         struct usb_yurex *dev;
355
356         dev = (struct usb_yurex *)file->private_data;
357         return fasync_helper(fd, file, on, &dev->async_queue);
358 }
359
360 static int yurex_open(struct inode *inode, struct file *file)
361 {
362         struct usb_yurex *dev;
363         struct usb_interface *interface;
364         int subminor;
365         int retval = 0;
366
367         subminor = iminor(inode);
368
369         interface = usb_find_interface(&yurex_driver, subminor);
370         if (!interface) {
371                 err("%s - error, can't find device for minor %d",
372                     __func__, subminor);
373                 retval = -ENODEV;
374                 goto exit;
375         }
376
377         dev = usb_get_intfdata(interface);
378         if (!dev) {
379                 retval = -ENODEV;
380                 goto exit;
381         }
382
383         /* increment our usage count for the device */
384         kref_get(&dev->kref);
385
386         /* save our object in the file's private structure */
387         mutex_lock(&dev->io_mutex);
388         file->private_data = dev;
389         mutex_unlock(&dev->io_mutex);
390
391 exit:
392         return retval;
393 }
394
395 static int yurex_release(struct inode *inode, struct file *file)
396 {
397         struct usb_yurex *dev;
398
399         dev = (struct usb_yurex *)file->private_data;
400         if (dev == NULL)
401                 return -ENODEV;
402
403         yurex_fasync(-1, file, 0);
404
405         /* decrement the count on our device */
406         kref_put(&dev->kref, yurex_delete);
407         return 0;
408 }
409
410 static ssize_t yurex_read(struct file *file, char *buffer, size_t count, loff_t *ppos)
411 {
412         struct usb_yurex *dev;
413         int retval = 0;
414         int bytes_read = 0;
415         char in_buffer[20];
416         unsigned long flags;
417
418         dev = (struct usb_yurex *)file->private_data;
419
420         mutex_lock(&dev->io_mutex);
421         if (!dev->interface) {          /* already disconnected */
422                 retval = -ENODEV;
423                 goto exit;
424         }
425
426         spin_lock_irqsave(&dev->lock, flags);
427         bytes_read = snprintf(in_buffer, 20, "%lld\n", dev->bbu);
428         spin_unlock_irqrestore(&dev->lock, flags);
429
430         if (*ppos < bytes_read) {
431                 if (copy_to_user(buffer, in_buffer + *ppos, bytes_read - *ppos))
432                         retval = -EFAULT;
433                 else {
434                         retval = bytes_read - *ppos;
435                         *ppos += bytes_read;
436                 }
437         }
438
439 exit:
440         mutex_unlock(&dev->io_mutex);
441         return retval;
442 }
443
444 static ssize_t yurex_write(struct file *file, const char *user_buffer, size_t count, loff_t *ppos)
445 {
446         struct usb_yurex *dev;
447         int i, set = 0, retval = 0;
448         char buffer[16];
449         char *data = buffer;
450         unsigned long long c, c2 = 0;
451         signed long timeout = 0;
452         DEFINE_WAIT(wait);
453
454         count = min(sizeof(buffer), count);
455         dev = (struct usb_yurex *)file->private_data;
456
457         /* verify that we actually have some data to write */
458         if (count == 0)
459                 goto error;
460
461         mutex_lock(&dev->io_mutex);
462         if (!dev->interface) {          /* alreaday disconnected */
463                 mutex_unlock(&dev->io_mutex);
464                 retval = -ENODEV;
465                 goto error;
466         }
467
468         if (copy_from_user(buffer, user_buffer, count)) {
469                 mutex_unlock(&dev->io_mutex);
470                 retval = -EFAULT;
471                 goto error;
472         }
473         memset(dev->cntl_buffer, CMD_PADDING, YUREX_BUF_SIZE);
474
475         switch (buffer[0]) {
476         case CMD_ANIMATE:
477         case CMD_LED:
478                 dev->cntl_buffer[0] = buffer[0];
479                 dev->cntl_buffer[1] = buffer[1];
480                 dev->cntl_buffer[2] = CMD_EOF;
481                 break;
482         case CMD_READ:
483         case CMD_VERSION:
484                 dev->cntl_buffer[0] = buffer[0];
485                 dev->cntl_buffer[1] = 0x00;
486                 dev->cntl_buffer[2] = CMD_EOF;
487                 break;
488         case CMD_SET:
489                 data++;
490                 /* FALL THROUGH */
491         case '0' ... '9':
492                 set = 1;
493                 c = c2 = simple_strtoull(data, NULL, 0);
494                 dev->cntl_buffer[0] = CMD_SET;
495                 for (i = 1; i < 6; i++) {
496                         dev->cntl_buffer[i] = (c>>32) & 0xff;
497                         c <<= 8;
498                 }
499                 buffer[6] = CMD_EOF;
500                 break;
501         default:
502                 mutex_unlock(&dev->io_mutex);
503                 return -EINVAL;
504         }
505
506         /* send the data as the control msg */
507         prepare_to_wait(&dev->waitq, &wait, TASK_INTERRUPTIBLE);
508         dbg("%s - submit %c", __func__, dev->cntl_buffer[0]);
509         retval = usb_submit_urb(dev->cntl_urb, GFP_KERNEL);
510         if (retval >= 0)
511                 timeout = schedule_timeout(YUREX_WRITE_TIMEOUT);
512         finish_wait(&dev->waitq, &wait);
513
514         mutex_unlock(&dev->io_mutex);
515
516         if (retval < 0) {
517                 err("%s - failed to send bulk msg, error %d", __func__, retval);
518                 goto error;
519         }
520         if (set && timeout)
521                 dev->bbu = c2;
522         return timeout ? count : -EIO;
523
524 error:
525         return retval;
526 }
527
528 static const struct file_operations yurex_fops = {
529         .owner =        THIS_MODULE,
530         .read =         yurex_read,
531         .write =        yurex_write,
532         .open =         yurex_open,
533         .release =      yurex_release,
534         .fasync =       yurex_fasync,
535         .llseek =       default_llseek,
536 };
537
538
539 static int __init usb_yurex_init(void)
540 {
541         int result;
542
543         /* register this driver with the USB subsystem */
544         result = usb_register(&yurex_driver);
545         if (result)
546                 err("usb_register failed. Error number %d", result);
547
548         return result;
549 }
550
551 static void __exit usb_yurex_exit(void)
552 {
553         /* deregister this driver with the USB subsystem */
554         usb_deregister(&yurex_driver);
555 }
556
557 module_init(usb_yurex_init);
558 module_exit(usb_yurex_exit);
559
560 MODULE_LICENSE("GPL");