aboutsummaryrefslogtreecommitdiff
path: root/drivers/input/evdev.c
blob: 17552a29978b862853e3bacf413547e2237e5931 (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
/*
 * Event char devices, giving access to raw input device events.
 *
 * Copyright (c) 1999-2002 Vojtech Pavlik
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 */

#define EVDEV_MINOR_BASE	64
#define EVDEV_MINORS		32
#define EVDEV_BUFFER_SIZE	64

#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/input.h>
#include <linux/major.h>
#include <linux/smp_lock.h>
#include <linux/device.h>
#include <linux/devfs_fs_kernel.h>

struct evdev {
	int exist;
	int open;
	int minor;
	char name[16];
	struct input_handle handle;
	wait_queue_head_t wait;
	struct evdev_list *grab;
	struct list_head list;
};

struct evdev_list {
	struct input_event buffer[EVDEV_BUFFER_SIZE];
	int head;
	int tail;
	struct fasync_struct *fasync;
	struct evdev *evdev;
	struct list_head node;
};

static struct evdev *evdev_table[EVDEV_MINORS];

static void evdev_event(struct input_handle *handle, unsigned int type, unsigned int code, int value)
{
	struct evdev *evdev = handle->private;
	struct evdev_list *list;

	if (evdev->grab) {
		list = evdev->grab;

		do_gettimeofday(&list->buffer[list->head].time);
		list->buffer[list->head].type = type;
		list->buffer[list->head].code = code;
		list->buffer[list->head].value = value;
		list->head = (list->head + 1) & (EVDEV_BUFFER_SIZE - 1);

		kill_fasync(&list->fasync, SIGIO, POLL_IN);
	} else
		list_for_each_entry(list, &evdev->list, node) {

			do_gettimeofday(&list->buffer[list->head].time);
			list->buffer[list->head].type = type;
			list->buffer[list->head].code = code;
			list->buffer[list->head].value = value;
			list->head = (list->head + 1) & (EVDEV_BUFFER_SIZE - 1);

			kill_fasync(&list->fasync, SIGIO, POLL_IN);
		}

	wake_up_interruptible(&evdev->wait);
}

static int evdev_fasync(int fd, struct file *file, int on)
{
	int retval;
	struct evdev_list *list = file->private_data;
	retval = fasync_helper(fd, file, on, &list->fasync);
	return retval < 0 ? retval : 0;
}

static int evdev_flush(struct file * file)
{
	struct evdev_list *list = file->private_data;
	if (!list->evdev->exist) return -ENODEV;
	return input_flush_device(&list->evdev->handle, file);
}

static void evdev_free(struct evdev *evdev)
{
	evdev_table[evdev->minor] = NULL;
	kfree(evdev);
}

static int evdev_release(struct inode * inode, struct file * file)
{
	struct evdev_list *list = file->private_data;

	if (list->evdev->grab == list) {
		input_release_device(&list->evdev->handle);
		list->evdev->grab = NULL;
	}

	evdev_fasync(-1, file, 0);
	list_del(&list->node);

	if (!--list->evdev->open) {
		if (list->evdev->exist)
			input_close_device(&list->evdev->handle);
		else
			evdev_free(list->evdev);
	}

	kfree(list);
	return 0;
}

static int evdev_open(struct inode * inode, struct file * file)
{
	struct evdev_list *list;
	int i = iminor(inode) - EVDEV_MINOR_BASE;
	int accept_err;

	if (i >= EVDEV_MINORS || !evdev_table[i] || !evdev_table[i]->exist)
		return -ENODEV;

	if ((accept_err = input_accept_process(&(evdev_table[i]->handle), file)))
		return accept_err;

	if (!(list = kmalloc(sizeof(struct evdev_list), GFP_KERNEL)))
		return -ENOMEM;
	memset(list, 0, sizeof(struct evdev_list));

	list->evdev = evdev_table[i];
	list_add_tail(&list->node, &evdev_table[i]->list);
	file->private_data = list;

	if (!list->evdev->open++)
		if (list->evdev->exist)
			input_open_device(&list->evdev->handle);

	return 0;
}

static ssize_t evdev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
{
	struct evdev_list *list = file->private_data;
	struct input_event event;
	int retval = 0;

	if (!list->evdev->exist) return -ENODEV;

	while (retval < count) {

		if (copy_from_user(&event, buffer + retval, sizeof(struct input_event)))
			return -EFAULT;
		input_event(list->evdev->handle.dev, event.type, event.code, event.value);
		retval += sizeof(struct input_event);
	}

	return retval;
}

static ssize_t evdev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
{
	struct evdev_list *list = file->private_data;
	int retval;

	if (count < sizeof(struct input_event))
		return -EINVAL;

	if (list->head == list->tail && list->evdev->exist && (file->f_flags & O_NONBLOCK))
		return -EAGAIN;

	retval = wait_event_interruptible(list->evdev->wait,
		list->head != list->tail || (!list->evdev->exist));

	if (retval)
		return retval;

	if (!list->evdev->exist)
		return -ENODEV;

	while (list->head != list->tail && retval + sizeof(struct input_event) <= count) {
		if (copy_to_user(buffer + retval, list->buffer + list->tail,
			 sizeof(struct input_event))) return -EFAULT;
		list->tail = (list->tail + 1) & (EVDEV_BUFFER_SIZE - 1);
		retval += sizeof(struct input_event);
	}

	return retval;
}

/* No kernel lock - fine */
static unsigned int evdev_poll(struct file *file, poll_table *wait)
{
	struct evdev_list *list = file->private_data;
	poll_wait(file, &list->evdev->wait, wait);
	return ((list->head == list->tail) ? 0 : (POLLIN | POLLRDNORM)) |
		(list->evdev->exist ? 0 : (POLLHUP | POLLERR));
}

static int evdev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
{
	struct evdev_list *list = file->private_data;
	struct evdev *evdev = list->evdev;
	struct input_dev *dev = evdev->handle.dev;
	struct input_absinfo abs;
	void __user *p = (void __user *)arg;
	int __user *ip = (int __user *)arg;
	int i, t, u, v;

	if (!evdev->exist) return -ENODEV;

	switch (cmd) {

		case EVIOCGVERSION:
			return put_user(EV_VERSION, ip);

		case EVIOCGID:
			return copy_to_user(p, &dev->id, sizeof(struct input_id)) ? -EFAULT : 0;

		case EVIOCGKEYCODE:
			if (get_user(t, ip)) return -EFAULT;
			if (t < 0 || t >= dev->keycodemax || !dev->keycodesize) return -EINVAL;
			if (put_user(INPUT_KEYCODE(dev, t), ip + 1)) return -EFAULT;
			return 0;

		case EVIOCSKEYCODE:
			if (get_user(t, ip)) return -EFAULT;
			if (t < 0 || t >= dev->keycodemax || !dev->keycodesize) return -EINVAL;
			if (get_user(v, ip + 1)) return -EFAULT;
			if (v < 0 || v > KEY_MAX) return -EINVAL;
			u = SET_INPUT_KEYCODE(dev, t, v);
			clear_bit(u, dev->keybit);
			set_bit(v, dev->keybit);
			for (i = 0; i < dev->keycodemax; i++)
				if (INPUT_KEYCODE(dev,i) == u)
					set_bit(u, dev->keybit);
			return 0;

		case EVIOCSFF:
			if (dev->upload_effect) {
				struct ff_effect effect;
				int err;

				if (copy_from_user(&effect, p, sizeof(effect)))
					return -EFAULT;
				err = dev->upload_effect(dev, &effect);
				if (put_user(effect.id, &(((struct ff_effect __user *)arg)->id)))
					return -EFAULT;
				return err;
			}
			else return -ENOSYS;

		case EVIOCRMFF:
			if (dev->erase_effect) {
				return dev->erase_effect(dev, (int)arg);
			}
			else return -ENOSYS;

		case EVIOCGEFFECTS:
			if (put_user(dev->ff_effects_max, ip))
				return -EFAULT;
			return 0;

		case EVIOCGRAB:
			if (arg) {
				if (evdev->grab)
					return -EBUSY;
				if (input_grab_device(&evdev->handle))
					return -EBUSY;
				evdev->grab = list;
				return 0;
			} else {
				if (evdev->grab != list)
					return -EINVAL;
				input_release_device(&evdev->handle);
				evdev->grab = NULL;
				return 0;
			}

		default:

			if (_IOC_TYPE(cmd) != 'E' || _IOC_DIR(cmd) != _IOC_READ)
				return -EINVAL;

			if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0,0))) {

				long *bits;
				int len;

				switch (_IOC_NR(cmd) & EV_MAX) {
					case      0: bits = dev->evbit;  len = EV_MAX;  break;
					case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
					case EV_REL: bits = dev->relbit; len = REL_MAX; break;
					case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
					case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break;
					case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
					case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
					case EV_FF:  bits = dev->ffbit;  len = FF_MAX;  break;
					default: return -EINVAL;
				}
				len = NBITS(len) * sizeof(long);
				if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
				return copy_to_user(p, bits, len) ? -EFAULT : len;
			}

			if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0))) {
				int len;
				len = NBITS(KEY_MAX) * sizeof(long);
				if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
				return copy_to_user(p, dev->key, len) ? -EFAULT : len;
			}

			if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0))) {
				int len;
				len = NBITS(LED_MAX) * sizeof(long);
				if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
				return copy_to_user(p, dev->led, len) ? -EFAULT : len;
			}

			if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0))) {
				int len;
				len = NBITS(SND_MAX) * sizeof(long);
				if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
				return copy_to_user(p, dev->snd, len) ? -EFAULT : len;
			}

			if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0))) {
				int len;
				if (!dev->name) return -ENOENT;
				len = strlen(dev->name) + 1;
				if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
				return copy_to_user(p, dev->name, len) ? -EFAULT : len;
			}

			if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0))) {
				int len;
				if (!dev->phys) return -ENOENT;
				len = strlen(dev->phys) + 1;
				if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
				return copy_to_user(p, dev->phys, len) ? -EFAULT : len;
			}

			if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0))) {
				int len;
				if (!dev->uniq) return -ENOENT;
				len = strlen(dev->uniq) + 1;
				if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
				return copy_to_user(p, dev->uniq, len) ? -EFAULT : len;
			}

			if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {

				int t = _IOC_NR(cmd) & ABS_MAX;

				abs.value = dev->abs[t];
				abs.minimum = dev->absmin[t];
				abs.maximum = dev->absmax[t];
				abs.fuzz = dev->absfuzz[t];
				abs.flat = dev->absflat[t];

				if (copy_to_user(p, &abs, sizeof(struct input_absinfo)))
					return -EFAULT;

				return 0;
			}

			if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {

				int t = _IOC_NR(cmd) & ABS_MAX;

				if (copy_from_user(&abs, p, sizeof(struct input_absinfo)))
					return -EFAULT;

				dev->abs[t] = abs.value;
				dev->absmin[t] = abs.minimum;
				dev->absmax[t] = abs.maximum;
				dev->absfuzz[t] = abs.fuzz;
				dev->absflat[t] = abs.flat;

				return 0;
			}
	}
	return -EINVAL;
}

static struct file_operations evdev_fops = {
	.owner =	THIS_MODULE,
	.read =		evdev_read,
	.write =	evdev_write,
	.poll =		evdev_poll,
	.open =		evdev_open,
	.release =	evdev_release,
	.ioctl =	evdev_ioctl,
	.fasync =	evdev_fasync,
	.flush =	evdev_flush
};

static struct input_handle *evdev_connect(struct input_handler *handler, struct input_dev *dev, struct input_device_id *id)
{
	struct evdev *evdev;
	int minor;

	for (minor = 0; minor < EVDEV_MINORS && evdev_table[minor]; minor++);
	if (minor == EVDEV_MINORS) {
		printk(KERN_ERR "evdev: no more free evdev devices\n");
		return NULL;
	}

	if (!(evdev = kmalloc(sizeof(struct evdev), GFP_KERNEL)))
		return NULL;
	memset(evdev, 0, sizeof(struct evdev));

	INIT_LIST_HEAD(&evdev->list);
	init_waitqueue_head(&evdev->wait);

	evdev->exist = 1;
	evdev->minor = minor;
	evdev->handle.dev = dev;
	evdev->handle.name = evdev->name;
	evdev->handle.handler = handler;
	evdev->handle.private = evdev;
	sprintf(evdev->name, "event%d", minor);

	evdev_table[minor] = evdev;

	devfs_mk_cdev(MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor),
			S_IFCHR|S_IRUGO|S_IWUSR, "input/event%d", minor);
	class_simple_device_add(input_class,
				MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor),
				dev->dev, "event%d", minor);

	return &evdev->handle;
}

static void evdev_disconnect(struct input_handle *handle)
{
	struct evdev *evdev = handle->private;
	struct evdev_list *list;

	class_simple_device_remove(MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + evdev->minor));
	devfs_remove("input/event%d", evdev->minor);
	evdev->exist = 0;

	if (evdev->open) {
		input_close_device(handle);
		wake_up_interruptible(&evdev->wait);
		list_for_each_entry(list, &evdev->list, node)
			kill_fasync(&list->fasync, SIGIO, POLL_HUP);
	} else
		evdev_free(evdev);
}

static struct input_device_id evdev_ids[] = {
	{ .driver_info = 1 },	/* Matches all devices */
	{ },			/* Terminating zero entry */
};

MODULE_DEVICE_TABLE(input, evdev_ids);

static struct input_handler evdev_handler = {
	.event =	evdev_event,
	.connect =	evdev_connect,
	.disconnect =	evdev_disconnect,
	.fops =		&evdev_fops,
	.minor =	EVDEV_MINOR_BASE,
	.name =		"evdev",
	.id_table =	evdev_ids,
};

static int __init evdev_init(void)
{
	input_register_handler(&evdev_handler);
	return 0;
}

static void __exit evdev_exit(void)
{
	input_unregister_handler(&evdev_handler);
}

module_init(evdev_init);
module_exit(evdev_exit);

MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
MODULE_DESCRIPTION("Input driver event char devices");
MODULE_LICENSE("GPL");