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