aboutsummaryrefslogtreecommitdiff
path: root/drivers/usb/misc/yurex.c
blob: b6ab515bfc6c0b1be593ed99e10e86391e012525 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
/*
 * Driver for Meywa-Denki & KAYAC YUREX
 *
 * Copyright (C) 2010 Tomoki Sekiyama (tomoki.sekiyama@gmail.com)
 *
 *	This program is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU General Public License as
 *	published by the Free Software Foundation, version 2.
 *
 */

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/kref.h>
#include <linux/mutex.h>
#include <linux/uaccess.h>
#include <linux/usb.h>
#include <linux/hid.h>

#define DRIVER_AUTHOR "Tomoki Sekiyama"
#define DRIVER_DESC "Driver for Meywa-Denki & KAYAC YUREX"

#define YUREX_VENDOR_ID		0x0c45
#define YUREX_PRODUCT_ID	0x1010

#define CMD_ACK		'!'
#define CMD_ANIMATE	'A'
#define CMD_COUNT	'C'
#define CMD_LED		'L'
#define CMD_READ	'R'
#define CMD_SET		'S'
#define CMD_VERSION	'V'
#define CMD_EOF		0x0d
#define CMD_PADDING	0xff

#define YUREX_BUF_SIZE		8
#define YUREX_WRITE_TIMEOUT	(HZ*2)

/* table of devices that work with this driver */
static struct usb_device_id yurex_table[] = {
	{ USB_DEVICE(YUREX_VENDOR_ID, YUREX_PRODUCT_ID) },
	{ }					/* Terminating entry */
};
MODULE_DEVICE_TABLE(usb, yurex_table);

#ifdef CONFIG_USB_DYNAMIC_MINORS
#define YUREX_MINOR_BASE	0
#else
#define YUREX_MINOR_BASE	192
#endif

/* Structure to hold all of our device specific stuff */
struct usb_yurex {
	struct usb_device	*udev;
	struct usb_interface	*interface;
	__u8			int_in_endpointAddr;
	struct urb		*urb;		/* URB for interrupt in */
	unsigned char           *int_buffer;	/* buffer for intterupt in */
	struct urb		*cntl_urb;	/* URB for control msg */
	struct usb_ctrlrequest	*cntl_req;	/* req for control msg */
	unsigned char		*cntl_buffer;	/* buffer for control msg */

	struct kref		kref;
	struct mutex		io_mutex;
	struct fasync_struct	*async_queue;
	wait_queue_head_t	waitq;

	spinlock_t		lock;
	__s64			bbu;		/* BBU from device */
};
#define to_yurex_dev(d) container_of(d, struct usb_yurex, kref)

static struct usb_driver yurex_driver;
static const struct file_operations yurex_fops;


static void yurex_control_callback(struct urb *urb)
{
	struct usb_yurex *dev = urb->context;
	int status = urb->status;

	if (status) {
		dev_err(&urb->dev->dev, "%s - control failed: %d\n",
			__func__, status);
		wake_up_interruptible(&dev->waitq);
		return;
	}
	/* on success, sender woken up by CMD_ACK int in, or timeout */
}

static void yurex_delete(struct kref *kref)
{
	struct usb_yurex *dev = to_yurex_dev(kref);

	dev_dbg(&dev->interface->dev, "%s\n", __func__);

	usb_put_dev(dev->udev);
	if (dev->cntl_urb) {
		usb_kill_urb(dev->cntl_urb);
		kfree(dev->cntl_req);
		if (dev->cntl_buffer)
			usb_free_coherent(dev->udev, YUREX_BUF_SIZE,
				dev->cntl_buffer, dev->cntl_urb->transfer_dma);
		usb_free_urb(dev->cntl_urb);
	}
	if (dev->urb) {
		usb_kill_urb(dev->urb);
		if (dev->int_buffer)
			usb_free_coherent(dev->udev, YUREX_BUF_SIZE,
				dev->int_buffer, dev->urb->transfer_dma);
		usb_free_urb(dev->urb);
	}
	kfree(dev);
}

/*
 * usb class driver info in order to get a minor number from the usb core,
 * and to have the device registered with the driver core
 */
static struct usb_class_driver yurex_class = {
	.name =		"yurex%d",
	.fops =		&yurex_fops,
	.minor_base =	YUREX_MINOR_BASE,
};

static void yurex_interrupt(struct urb *urb)
{
	struct usb_yurex *dev = urb->context;
	unsigned char *buf = dev->int_buffer;
	int status = urb->status;
	unsigned long flags;
	int retval, i;

	switch (status) {
	case 0: /*success*/
		break;
	case -EOVERFLOW:
		dev_err(&dev->interface->dev,
			"%s - overflow with length %d, actual length is %d\n",
			__func__, YUREX_BUF_SIZE, dev->urb->actual_length);
	case -ECONNRESET:
	case -ENOENT:
	case -ESHUTDOWN:
	case -EILSEQ:
		/* The device is terminated, clean up */
		return;
	default:
		dev_err(&dev->interface->dev,
			"%s - unknown status received: %d\n", __func__, status);
		goto exit;
	}

	/* handle received message */
	switch (buf[0]) {
	case CMD_COUNT:
	case CMD_READ:
		if (buf[6] == CMD_EOF) {
			spin_lock_irqsave(&dev->lock, flags);
			dev->bbu = 0;
			for (i = 1; i < 6; i++) {
				dev->bbu += buf[i];
				if (i != 5)
					dev->bbu <<= 8;
			}
			dev_dbg(&dev->interface->dev, "%s count: %lld\n",
				__func__, dev->bbu);
			spin_unlock_irqrestore(&dev->lock, flags);

			kill_fasync(&dev->async_queue, SIGIO, POLL_IN);
		}
		else
			dev_dbg(&dev->interface->dev,
				"data format error - no EOF\n");
		break;
	case CMD_ACK:
		dev_dbg(&dev->interface->dev, "%s ack: %c\n",
			__func__, buf[1]);
		wake_up_interruptible(&dev->waitq);
		break;
	}

exit:
	retval = usb_submit_urb(dev->urb, GFP_ATOMIC);
	if (retval) {
		dev_err(&dev->interface->dev, "%s - usb_submit_urb failed: %d\n",
			__func__, retval);
	}
}

static int yurex_probe(struct usb_interface *interface, const struct usb_device_id *id)
{
	struct usb_yurex *dev;
	struct usb_host_interface *iface_desc;
	struct usb_endpoint_descriptor *endpoint;
	int retval = -ENOMEM;
	int i;
	DEFINE_WAIT(wait);

	/* allocate memory for our device state and initialize it */
	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
	if (!dev) {
		dev_err(&interface->dev, "Out of memory\n");
		goto error;
	}
	kref_init(&dev->kref);
	mutex_init(&dev->io_mutex);
	spin_lock_init(&dev->lock);
	init_waitqueue_head(&dev->waitq);

	dev->udev = usb_get_dev(interface_to_usbdev(interface));
	dev->interface = interface;

	/* set up the endpoint information */
	iface_desc = interface->cur_altsetting;
	for (i = 0; i < iface_desc->desc.bNumEndpoints; i++) {
		endpoint = &iface_desc->endpoint[i].desc;

		if (usb_endpoint_is_int_in(endpoint)) {
			dev->int_in_endpointAddr = endpoint->bEndpointAddress;
			break;
		}
	}
	if (!dev->int_in_endpointAddr) {
		retval = -ENODEV;
		dev_err(&interface->dev, "Could not find endpoints\n");
		goto error;
	}


	/* allocate control URB */
	dev->cntl_urb = usb_alloc_urb(0, GFP_KERNEL);
	if (!dev->cntl_urb) {
		dev_err(&interface->dev, "Could not allocate control URB\n");
		goto error;
	}

	/* allocate buffer for control req */
	dev->cntl_req = kmalloc(YUREX_BUF_SIZE, GFP_KERNEL);
	if (!dev->cntl_req) {
		dev_err(&interface->dev, "Could not allocate cntl_req\n");
		goto error;
	}

	/* allocate buffer for control msg */
	dev->cntl_buffer = usb_alloc_coherent(dev->udev, YUREX_BUF_SIZE,
					      GFP_KERNEL,
					      &dev->cntl_urb->transfer_dma);
	if (!dev->cntl_buffer) {
		dev_err(&interface->dev, "Could not allocate cntl_buffer\n");
		goto error;
	}

	/* configure control URB */
	dev->cntl_req->bRequestType = USB_DIR_OUT | USB_TYPE_CLASS |
				      USB_RECIP_INTERFACE;
	dev->cntl_req->bRequest	= HID_REQ_SET_REPORT;
	dev->cntl_req->wValue	= cpu_to_le16((HID_OUTPUT_REPORT + 1) << 8);
	dev->cntl_req->wIndex	= cpu_to_le16(iface_desc->desc.bInterfaceNumber);
	dev->cntl_req->wLength	= cpu_to_le16(YUREX_BUF_SIZE);

	usb_fill_control_urb(dev->cntl_urb, dev->udev,
			     usb_sndctrlpipe(dev->udev, 0),
			     (void *)dev->cntl_req, dev->cntl_buffer,
			     YUREX_BUF_SIZE, yurex_control_callback, dev);
	dev->cntl_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;


	/* allocate interrupt URB */
	dev->urb = usb_alloc_urb(0, GFP_KERNEL);
	if (!dev->urb) {
		dev_err(&interface->dev, "Could not allocate URB\n");
		goto error;
	}

	/* allocate buffer for interrupt in */
	dev->int_buffer = usb_alloc_coherent(dev->udev, YUREX_BUF_SIZE,
					GFP_KERNEL, &dev->urb->transfer_dma);
	if (!dev->int_buffer) {
		dev_err(&interface->dev, "Could not allocate int_buffer\n");
		goto error;
	}

	/* configure interrupt URB */
	usb_fill_int_urb(dev->urb, dev->udev,
			 usb_rcvintpipe(dev->udev, dev->int_in_endpointAddr),
			 dev->int_buffer, YUREX_BUF_SIZE, yurex_interrupt,
			 dev, 1);
	dev->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
	if (usb_submit_urb(dev->urb, GFP_KERNEL)) {
		retval = -EIO;
		dev_err(&interface->dev, "Could not submitting URB\n");
		goto error;
	}

	/* save our data pointer in this interface device */
	usb_set_intfdata(interface, dev);

	/* we can register the device now, as it is ready */
	retval = usb_register_dev(interface, &yurex_class);
	if (retval) {
		dev_err(&interface->dev,
			"Not able to get a minor for this device.\n");
		usb_set_intfdata(interface, NULL);
		goto error;
	}

	dev->bbu = -1;

	dev_info(&interface->dev,
		 "USB YUREX device now attached to Yurex #%d\n",
		 interface->minor);

	return 0;

error:
	if (dev)
		/* this frees allocated memory */
		kref_put(&dev->kref, yurex_delete);
	return retval;
}

static void yurex_disconnect(struct usb_interface *interface)
{
	struct usb_yurex *dev;
	int minor = interface->minor;

	dev = usb_get_intfdata(interface);
	usb_set_intfdata(interface, NULL);

	/* give back our minor */
	usb_deregister_dev(interface, &yurex_class);

	/* prevent more I/O from starting */
	mutex_lock(&dev->io_mutex);
	dev->interface = NULL;
	mutex_unlock(&dev->io_mutex);

	/* wakeup waiters */
	kill_fasync(&dev->async_queue, SIGIO, POLL_IN);
	wake_up_interruptible(&dev->waitq);

	/* decrement our usage count */
	kref_put(&dev->kref, yurex_delete);

	dev_info(&interface->dev, "USB YUREX #%d now disconnected\n", minor);
}

static struct usb_driver yurex_driver = {
	.name =		"yurex",
	.probe =	yurex_probe,
	.disconnect =	yurex_disconnect,
	.id_table =	yurex_table,
};


static int yurex_fasync(int fd, struct file *file, int on)
{
	struct usb_yurex *dev;

	dev = (struct usb_yurex *)file->private_data;
	return fasync_helper(fd, file, on, &dev->async_queue);
}

static int yurex_open(struct inode *inode, struct file *file)
{
	struct usb_yurex *dev;
	struct usb_interface *interface;
	int subminor;
	int retval = 0;

	subminor = iminor(inode);

	interface = usb_find_interface(&yurex_driver, subminor);
	if (!interface) {
		printk(KERN_ERR "%s - error, can't find device for minor %d",
		       __func__, subminor);
		retval = -ENODEV;
		goto exit;
	}

	dev = usb_get_intfdata(interface);
	if (!dev) {
		retval = -ENODEV;
		goto exit;
	}

	/* increment our usage count for the device */
	kref_get(&dev->kref);

	/* save our object in the file's private structure */
	mutex_lock(&dev->io_mutex);
	file->private_data = dev;
	mutex_unlock(&dev->io_mutex);

exit:
	return retval;
}

static int yurex_release(struct inode *inode, struct file *file)
{
	struct usb_yurex *dev;

	dev = (struct usb_yurex *)file->private_data;
	if (dev == NULL)
		return -ENODEV;

	/* decrement the count on our device */
	kref_put(&dev->kref, yurex_delete);
	return 0;
}

static ssize_t yurex_read(struct file *file, char *buffer, size_t count, loff_t *ppos)
{
	struct usb_yurex *dev;
	int retval = 0;
	int bytes_read = 0;
	char in_buffer[20];
	unsigned long flags;

	dev = (struct usb_yurex *)file->private_data;

	mutex_lock(&dev->io_mutex);
	if (!dev->interface) {		/* already disconnected */
		retval = -ENODEV;
		goto exit;
	}

	spin_lock_irqsave(&dev->lock, flags);
	bytes_read = snprintf(in_buffer, 20, "%lld\n", dev->bbu);
	spin_unlock_irqrestore(&dev->lock, flags);

	if (*ppos < bytes_read) {
		if (copy_to_user(buffer, in_buffer + *ppos, bytes_read - *ppos))
			retval = -EFAULT;
		else {
			retval = bytes_read - *ppos;
			*ppos += bytes_read;
		}
	}

exit:
	mutex_unlock(&dev->io_mutex);
	return retval;
}

static ssize_t yurex_write(struct file *file, const char *user_buffer, size_t count, loff_t *ppos)
{
	struct usb_yurex *dev;
	int i, set = 0, retval = 0;
	char buffer[16];
	char *data = buffer;
	unsigned long long c, c2 = 0;
	signed long timeout = 0;
	DEFINE_WAIT(wait);

	count = min(sizeof(buffer), count);
	dev = (struct usb_yurex *)file->private_data;

	/* verify that we actually have some data to write */
	if (count == 0)
		goto error;

	mutex_lock(&dev->io_mutex);
	if (!dev->interface) {		/* alreaday disconnected */
		mutex_unlock(&dev->io_mutex);
		retval = -ENODEV;
		goto error;
	}

	if (copy_from_user(buffer, user_buffer, count)) {
		mutex_unlock(&dev->io_mutex);
		retval = -EFAULT;
		goto error;
	}
	memset(dev->cntl_buffer, CMD_PADDING, YUREX_BUF_SIZE);

	switch (buffer[0]) {
	case CMD_ANIMATE:
	case CMD_LED:
		dev->cntl_buffer[0] = buffer[0];
		dev->cntl_buffer[1] = buffer[1];
		dev->cntl_buffer[2] = CMD_EOF;
		break;
	case CMD_READ:
	case CMD_VERSION:
		dev->cntl_buffer[0] = buffer[0];
		dev->cntl_buffer[1] = 0x00;
		dev->cntl_buffer[2] = CMD_EOF;
		break;
	case CMD_SET:
		data++;
		/* FALL THROUGH */
	case '0' ... '9':
		set = 1;
		c = c2 = simple_strtoull(data, NULL, 0);
		dev->cntl_buffer[0] = CMD_SET;
		for (i = 1; i < 6; i++) {
			dev->cntl_buffer[i] = (c>>32) & 0xff;
			c <<= 8;
		}
		buffer[6] = CMD_EOF;
		break;
	default:
		mutex_unlock(&dev->io_mutex);
		return -EINVAL;
	}

	/* send the data as the control msg */
	prepare_to_wait(&dev->waitq, &wait, TASK_INTERRUPTIBLE);
	dev_dbg(&dev->interface->dev, "%s - submit %c\n", __func__,
		dev->cntl_buffer[0]);
	retval = usb_submit_urb(dev->cntl_urb, GFP_KERNEL);
	if (retval >= 0)
		timeout = schedule_timeout(YUREX_WRITE_TIMEOUT);
	finish_wait(&dev->waitq, &wait);

	mutex_unlock(&dev->io_mutex);

	if (retval < 0) {
		dev_err(&dev->interface->dev,
			"%s - failed to send bulk msg, error %d\n",
			__func__, retval);
		goto error;
	}
	if (set && timeout)
		dev->bbu = c2;
	return timeout ? count : -EIO;

error:
	return retval;
}

static const struct file_operations yurex_fops = {
	.owner =	THIS_MODULE,
	.read =		yurex_read,
	.write =	yurex_write,
	.open =		yurex_open,
	.release =	yurex_release,
	.fasync	=	yurex_fasync,
	.llseek =	default_llseek,
};

module_usb_driver(yurex_driver);

MODULE_LICENSE("GPL");