aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/input/misc/uinput.c
blob: a56ad4ba8fe2eb482ee4a26f1f36baa56753e1c5 (plain) (blame)
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
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
/*
 *  User level driver support for input subsystem
 *
 * Heavily based on evdev.c by Vojtech Pavlik
 *
 * 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; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 * Author: Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
 *
 * Changes/Revisions:
 *	0.3	09/04/2006 (Anssi Hannula <anssi.hannula@gmail.com>)
 *		- updated ff support for the changes in kernel interface
 *		- added MODULE_VERSION
 *	0.2	16/10/2004 (Micah Dowty <micah@navi.cx>)
 *		- added force feedback support
 *              - added UI_SET_PHYS
 *	0.1	20/06/2002
 *		- first public version
 */
#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/smp_lock.h>
#include <linux/fs.h>
#include <linux/miscdevice.h>
#include <linux/uinput.h>

static int uinput_dev_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)
{
	struct uinput_device	*udev = input_get_drvdata(dev);

	udev->buff[udev->head].type = type;
	udev->buff[udev->head].code = code;
	udev->buff[udev->head].value = value;
	do_gettimeofday(&udev->buff[udev->head].time);
	udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;

	wake_up_interruptible(&udev->waitq);

	return 0;
}

static int uinput_request_alloc_id(struct uinput_device *udev, struct uinput_request *request)
{
	/* Atomically allocate an ID for the given request. Returns 0 on success. */
	int id;
	int err = -1;

	spin_lock(&udev->requests_lock);

	for (id = 0; id < UINPUT_NUM_REQUESTS; id++)
		if (!udev->requests[id]) {
			request->id = id;
			udev->requests[id] = request;
			err = 0;
			break;
		}

	spin_unlock(&udev->requests_lock);
	return err;
}

static struct uinput_request* uinput_request_find(struct uinput_device *udev, int id)
{
	/* Find an input request, by ID. Returns NULL if the ID isn't valid. */
	if (id >= UINPUT_NUM_REQUESTS || id < 0)
		return NULL;
	return udev->requests[id];
}

static inline int uinput_request_reserve_slot(struct uinput_device *udev, struct uinput_request *request)
{
	/* Allocate slot. If none are available right away, wait. */
	return wait_event_interruptible(udev->requests_waitq,
					!uinput_request_alloc_id(udev, request));
}

static void uinput_request_done(struct uinput_device *udev, struct uinput_request *request)
{
	/* Mark slot as available */
	udev->requests[request->id] = NULL;
	wake_up(&udev->requests_waitq);

	complete(&request->done);
}

static int uinput_request_submit(struct input_dev *dev, struct uinput_request *request)
{
	/* Tell our userspace app about this new request by queueing an input event */
	uinput_dev_event(dev, EV_UINPUT, request->code, request->id);

	/* Wait for the request to complete */
	wait_for_completion(&request->done);
	return request->retval;
}

static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
{
	uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
}

static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
{
	uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
}

static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value)
{
	return uinput_dev_event(dev, EV_FF, effect_id, value);
}

static int uinput_dev_upload_effect(struct input_dev *dev, struct ff_effect *effect, struct ff_effect *old)
{
	struct uinput_request request;
	int retval;

	request.id = -1;
	init_completion(&request.done);
	request.code = UI_FF_UPLOAD;
	request.u.upload.effect = effect;
	request.u.upload.old = old;

	retval = uinput_request_reserve_slot(input_get_drvdata(dev), &request);
	if (!retval)
		retval = uinput_request_submit(dev, &request);

	return retval;
}

static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
{
	struct uinput_request request;
	int retval;

	if (!test_bit(EV_FF, dev->evbit))
		return -ENOSYS;

	request.id = -1;
	init_completion(&request.done);
	request.code = UI_FF_ERASE;
	request.u.effect_id = effect_id;

	retval = uinput_request_reserve_slot(input_get_drvdata(dev), &request);
	if (!retval)
		retval = uinput_request_submit(dev, &request);

	return retval;
}

static void uinput_destroy_device(struct uinput_device *udev)
{
	const char *name, *phys;

	if (udev->dev) {
		name = udev->dev->name;
		phys = udev->dev->phys;
		if (udev->state == UIST_CREATED)
			input_unregister_device(udev->dev);
		else
			input_free_device(udev->dev);
		kfree(name);
		kfree(phys);
		udev->dev = NULL;
	}

	udev->state = UIST_NEW_DEVICE;
}

static int uinput_create_device(struct uinput_device *udev)
{
	struct input_dev *dev = udev->dev;
	int error;

	if (udev->state != UIST_SETUP_COMPLETE) {
		printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
		return -EINVAL;
	}

	if (udev->ff_effects_max) {
		error = input_ff_create(dev, udev->ff_effects_max);
		if (error)
			goto fail1;

		dev->ff->upload = uinput_dev_upload_effect;
		dev->ff->erase = uinput_dev_erase_effect;
		dev->ff->playback = uinput_dev_playback;
		dev->ff->set_gain = uinput_dev_set_gain;
		dev->ff->set_autocenter = uinput_dev_set_autocenter;
	}

	error = input_register_device(udev->dev);
	if (error)
		goto fail2;

	udev->state = UIST_CREATED;

	return 0;

 fail2:	input_ff_destroy(dev);
 fail1: uinput_destroy_device(udev);
	return error;
}

static int uinput_open(struct inode *inode, struct file *file)
{
	struct uinput_device *newdev;

	newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
	if (!newdev)
		return -ENOMEM;

	mutex_init(&newdev->mutex);
	spin_lock_init(&newdev->requests_lock);
	init_waitqueue_head(&newdev->requests_waitq);
	init_waitqueue_head(&newdev->waitq);
	newdev->state = UIST_NEW_DEVICE;

	file->private_data = newdev;

	return 0;
}

static int uinput_validate_absbits(struct input_dev *dev)
{
	unsigned int cnt;
	int retval = 0;

	for (cnt = 0; cnt < ABS_MAX + 1; cnt++) {
		if (!test_bit(cnt, dev->absbit))
			continue;

		if ((dev->absmax[cnt] <= dev->absmin[cnt])) {
			printk(KERN_DEBUG
				"%s: invalid abs[%02x] min:%d max:%d\n",
				UINPUT_NAME, cnt,
				dev->absmin[cnt], dev->absmax[cnt]);
			retval = -EINVAL;
			break;
		}

		if (dev->absflat[cnt] > (dev->absmax[cnt] - dev->absmin[cnt])) {
			printk(KERN_DEBUG
				"%s: absflat[%02x] out of range: %d "
				"(min:%d/max:%d)\n",
				UINPUT_NAME, cnt, dev->absflat[cnt],
				dev->absmin[cnt], dev->absmax[cnt]);
			retval = -EINVAL;
			break;
		}
	}
	return retval;
}

static int uinput_allocate_device(struct uinput_device *udev)
{
	udev->dev = input_allocate_device();
	if (!udev->dev)
		return -ENOMEM;

	udev->dev->event = uinput_dev_event;
	input_set_drvdata(udev->dev, udev);

	return 0;
}

static int uinput_setup_device(struct uinput_device *udev, const char __user *buffer, size_t count)
{
	struct uinput_user_dev	*user_dev;
	struct input_dev	*dev;
	char			*name;
	int			size;
	int			retval;

	if (count != sizeof(struct uinput_user_dev))
		return -EINVAL;

	if (!udev->dev) {
		retval = uinput_allocate_device(udev);
		if (retval)
			return retval;
	}

	dev = udev->dev;

	user_dev = kmalloc(sizeof(struct uinput_user_dev), GFP_KERNEL);
	if (!user_dev)
		return -ENOMEM;

	if (copy_from_user(user_dev, buffer, sizeof(struct uinput_user_dev))) {
		retval = -EFAULT;
		goto exit;
	}

	udev->ff_effects_max = user_dev->ff_effects_max;

	size = strnlen(user_dev->name, UINPUT_MAX_NAME_SIZE) + 1;
	if (!size) {
		retval = -EINVAL;
		goto exit;
	}

	kfree(dev->name);
	dev->name = name = kmalloc(size, GFP_KERNEL);
	if (!name) {
		retval = -ENOMEM;
		goto exit;
	}
	strlcpy(name, user_dev->name, size);

	dev->id.bustype	= user_dev->id.bustype;
	dev->id.vendor	= user_dev->id.vendor;
	dev->id.product	= user_dev->id.product;
	dev->id.version	= user_dev->id.version;

	size = sizeof(int) * (ABS_MAX + 1);
	memcpy(dev->absmax, user_dev->absmax, size);
	memcpy(dev->absmin, user_dev->absmin, size);
	memcpy(dev->absfuzz, user_dev->absfuzz, size);
	memcpy(dev->absflat, user_dev->absflat, size);

	/* check if absmin/absmax/absfuzz/absflat are filled as
	 * told in Documentation/input/input-programming.txt */
	if (test_bit(EV_ABS, dev->evbit)) {
		retval = uinput_validate_absbits(dev);
		if (retval < 0)
			goto exit;
	}

	udev->state = UIST_SETUP_COMPLETE;
	retval = count;

 exit:
	kfree(user_dev);
	return retval;
}

static inline ssize_t uinput_inject_event(struct uinput_device *udev, const char __user *buffer, size_t count)
{
	struct input_event ev;

	if (count != sizeof(struct input_event))
		return -EINVAL;

	if (copy_from_user(&ev, buffer, sizeof(struct input_event)))
		return -EFAULT;

	input_event(udev->dev, ev.type, ev.code, ev.value);

	return sizeof(struct input_event);
}

static ssize_t uinput_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
{
	struct uinput_device *udev = file->private_data;
	int retval;

	retval = mutex_lock_interruptible(&udev->mutex);
	if (retval)
		return retval;

	retval = udev->state == UIST_CREATED ?
			uinput_inject_event(udev, buffer, count) :
			uinput_setup_device(udev, buffer, count);

	mutex_unlock(&udev->mutex);

	return retval;
}

static ssize_t uinput_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
{
	struct uinput_device *udev = file->private_data;
	int retval = 0;

	if (udev->state != UIST_CREATED)
		return -ENODEV;

	if (udev->head == udev->tail && (file->f_flags & O_NONBLOCK))
		return -EAGAIN;

	retval = wait_event_interruptible(udev->waitq,
			udev->head != udev->tail || udev->state != UIST_CREATED);
	if (retval)
		return retval;

	retval = mutex_lock_interruptible(&udev->mutex);
	if (retval)
		return retval;

	if (udev->state != UIST_CREATED) {
		retval = -ENODEV;
		goto out;
	}

	while (udev->head != udev->tail && retval + sizeof(struct input_event) <= count) {
		if (copy_to_user(buffer + retval, &udev->buff[udev->tail], sizeof(struct input_event))) {
			retval = -EFAULT;
			goto out;
		}
		udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
		retval += sizeof(struct input_event);
	}

 out:
	mutex_unlock(&udev->mutex);

	return retval;
}

static unsigned int uinput_poll(struct file *file, poll_table *wait)
{
	struct uinput_device *udev = file->private_data;

	poll_wait(file, &udev->waitq, wait);

	if (udev->head != udev->tail)
		return POLLIN | POLLRDNORM;

	return 0;
}

static int uinput_release(struct inode *inode, struct file *file)
{
	struct uinput_device *udev = file->private_data;

	uinput_destroy_device(udev);
	kfree(udev);

	return 0;
}

#define uinput_set_bit(_arg, _bit, _max)		\
({							\
	int __ret = 0;					\
	if (udev->state == UIST_CREATED)		\
		__ret =  -EINVAL;			\
	else if ((_arg) > (_max))			\
		__ret = -EINVAL;			\
	else set_bit((_arg), udev->dev->_bit);		\
	__ret;						\
})

static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	int			retval;
	struct uinput_device	*udev;
	void __user             *p = (void __user *)arg;
	struct uinput_ff_upload ff_up;
	struct uinput_ff_erase  ff_erase;
	struct uinput_request   *req;
	int                     length;
	char			*phys;

	udev = file->private_data;

	retval = mutex_lock_interruptible(&udev->mutex);
	if (retval)
		return retval;

	if (!udev->dev) {
		retval = uinput_allocate_device(udev);
		if (retval)
			goto out;
	}

	switch (cmd) {
		case UI_DEV_CREATE:
			retval = uinput_create_device(udev);
			break;

		case UI_DEV_DESTROY:
			uinput_destroy_device(udev);
			break;

		case UI_SET_EVBIT:
			retval = uinput_set_bit(arg, evbit, EV_MAX);
			break;

		case UI_SET_KEYBIT:
			retval = uinput_set_bit(arg, keybit, KEY_MAX);
			break;

		case UI_SET_RELBIT:
			retval = uinput_set_bit(arg, relbit, REL_MAX);
			break;

		case UI_SET_ABSBIT:
			retval = uinput_set_bit(arg, absbit, ABS_MAX);
			break;

		case UI_SET_MSCBIT:
			retval = uinput_set_bit(arg, mscbit, MSC_MAX);
			break;

		case UI_SET_LEDBIT:
			retval = uinput_set_bit(arg, ledbit, LED_MAX);
			break;

		case UI_SET_SNDBIT:
			retval = uinput_set_bit(arg, sndbit, SND_MAX);
			break;

		case UI_SET_FFBIT:
			retval = uinput_set_bit(arg, ffbit, FF_MAX);
			break;

		case UI_SET_SWBIT:
			retval = uinput_set_bit(arg, swbit, SW_MAX);
			break;

		case UI_SET_PHYS:
			if (udev->state == UIST_CREATED) {
				retval = -EINVAL;
				goto out;
			}
			length = strnlen_user(p, 1024);
			if (length <= 0) {
				retval = -EFAULT;
				break;
			}
			kfree(udev->dev->phys);
			udev->dev->phys = phys = kmalloc(length, GFP_KERNEL);
			if (!phys) {
				retval = -ENOMEM;
				break;
			}
			if (copy_from_user(phys, p, length)) {
				udev->dev->phys = NULL;
				kfree(phys);
				retval = -EFAULT;
				break;
			}
			phys[length - 1] = '\0';
			break;

		case UI_BEGIN_FF_UPLOAD:
			if (copy_from_user(&ff_up, p, sizeof(ff_up))) {
				retval = -EFAULT;
				break;
			}
			req = uinput_request_find(udev, ff_up.request_id);
			if (!(req && req->code == UI_FF_UPLOAD && req->u.upload.effect)) {
				retval = -EINVAL;
				break;
			}
			ff_up.retval = 0;
			memcpy(&ff_up.effect, req->u.upload.effect, sizeof(struct ff_effect));
			if (req->u.upload.old)
				memcpy(&ff_up.old, req->u.upload.old, sizeof(struct ff_effect));
			else
				memset(&ff_up.old, 0, sizeof(struct ff_effect));

			if (copy_to_user(p, &ff_up, sizeof(ff_up))) {
				retval = -EFAULT;
				break;
			}
			break;

		case UI_BEGIN_FF_ERASE:
			if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
				retval = -EFAULT;
				break;
			}
			req = uinput_request_find(udev, ff_erase.request_id);
			if (!(req && req->code == UI_FF_ERASE)) {
				retval = -EINVAL;
				break;
			}
			ff_erase.retval = 0;
			ff_erase.effect_id = req->u.effect_id;
			if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
				retval = -EFAULT;
				break;
			}
			break;

		case UI_END_FF_UPLOAD:
			if (copy_from_user(&ff_up, p, sizeof(ff_up))) {
				retval = -EFAULT;
				break;
			}
			req = uinput_request_find(udev, ff_up.request_id);
			if (!(req && req->code == UI_FF_UPLOAD && req->u.upload.effect)) {
				retval = -EINVAL;
				break;
			}
			req->retval = ff_up.retval;
			uinput_request_done(udev, req);
			break;

		case UI_END_FF_ERASE:
			if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
				retval = -EFAULT;
				break;
			}
			req = uinput_request_find(udev, ff_erase.request_id);
			if (!(req && req->code == UI_FF_ERASE)) {
				retval = -EINVAL;
				break;
			}
			req->retval = ff_erase.retval;
			uinput_request_done(udev, req);
			break;

		default:
			retval = -EINVAL;
	}

 out:
	mutex_unlock(&udev->mutex);
	return retval;
}

static const struct file_operations uinput_fops = {
	.owner		= THIS_MODULE,
	.open		= uinput_open,
	.release	= uinput_release,
	.read		= uinput_read,
	.write		= uinput_write,
	.poll		= uinput_poll,
	.unlocked_ioctl	= uinput_ioctl,
};

static struct miscdevice uinput_misc = {
	.fops		= &uinput_fops,
	.minor		= UINPUT_MINOR,
	.name		= UINPUT_NAME,
};

static int __init uinput_init(void)
{
	return misc_register(&uinput_misc);
}

static void __exit uinput_exit(void)
{
	misc_deregister(&uinput_misc);
}

MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
MODULE_DESCRIPTION("User level driver support for input subsystem");
MODULE_LICENSE("GPL");
MODULE_VERSION("0.3");

module_init(uinput_init);
module_exit(uinput_exit);