xref: /linux/drivers/input/evdev.c (revision d67b569f5f620c0fb95d5212642746b7ba9d29e4)
1 /*
2  * Event char devices, giving access to raw input device events.
3  *
4  * Copyright (c) 1999-2002 Vojtech Pavlik
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License version 2 as published by
8  * the Free Software Foundation.
9  */
10 
11 #define EVDEV_MINOR_BASE	64
12 #define EVDEV_MINORS		32
13 #define EVDEV_BUFFER_SIZE	64
14 
15 #include <linux/poll.h>
16 #include <linux/slab.h>
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/input.h>
20 #include <linux/major.h>
21 #include <linux/smp_lock.h>
22 #include <linux/device.h>
23 #include <linux/devfs_fs_kernel.h>
24 #include <linux/compat.h>
25 
26 struct evdev {
27 	int exist;
28 	int open;
29 	int minor;
30 	char name[16];
31 	struct input_handle handle;
32 	wait_queue_head_t wait;
33 	struct evdev_list *grab;
34 	struct list_head list;
35 };
36 
37 struct evdev_list {
38 	struct input_event buffer[EVDEV_BUFFER_SIZE];
39 	int head;
40 	int tail;
41 	struct fasync_struct *fasync;
42 	struct evdev *evdev;
43 	struct list_head node;
44 };
45 
46 static struct evdev *evdev_table[EVDEV_MINORS];
47 
48 static void evdev_event(struct input_handle *handle, unsigned int type, unsigned int code, int value)
49 {
50 	struct evdev *evdev = handle->private;
51 	struct evdev_list *list;
52 
53 	if (evdev->grab) {
54 		list = evdev->grab;
55 
56 		do_gettimeofday(&list->buffer[list->head].time);
57 		list->buffer[list->head].type = type;
58 		list->buffer[list->head].code = code;
59 		list->buffer[list->head].value = value;
60 		list->head = (list->head + 1) & (EVDEV_BUFFER_SIZE - 1);
61 
62 		kill_fasync(&list->fasync, SIGIO, POLL_IN);
63 	} else
64 		list_for_each_entry(list, &evdev->list, node) {
65 
66 			do_gettimeofday(&list->buffer[list->head].time);
67 			list->buffer[list->head].type = type;
68 			list->buffer[list->head].code = code;
69 			list->buffer[list->head].value = value;
70 			list->head = (list->head + 1) & (EVDEV_BUFFER_SIZE - 1);
71 
72 			kill_fasync(&list->fasync, SIGIO, POLL_IN);
73 		}
74 
75 	wake_up_interruptible(&evdev->wait);
76 }
77 
78 static int evdev_fasync(int fd, struct file *file, int on)
79 {
80 	int retval;
81 	struct evdev_list *list = file->private_data;
82 	retval = fasync_helper(fd, file, on, &list->fasync);
83 	return retval < 0 ? retval : 0;
84 }
85 
86 static int evdev_flush(struct file * file)
87 {
88 	struct evdev_list *list = file->private_data;
89 	if (!list->evdev->exist) return -ENODEV;
90 	return input_flush_device(&list->evdev->handle, file);
91 }
92 
93 static void evdev_free(struct evdev *evdev)
94 {
95 	evdev_table[evdev->minor] = NULL;
96 	kfree(evdev);
97 }
98 
99 static int evdev_release(struct inode * inode, struct file * file)
100 {
101 	struct evdev_list *list = file->private_data;
102 
103 	if (list->evdev->grab == list) {
104 		input_release_device(&list->evdev->handle);
105 		list->evdev->grab = NULL;
106 	}
107 
108 	evdev_fasync(-1, file, 0);
109 	list_del(&list->node);
110 
111 	if (!--list->evdev->open) {
112 		if (list->evdev->exist)
113 			input_close_device(&list->evdev->handle);
114 		else
115 			evdev_free(list->evdev);
116 	}
117 
118 	kfree(list);
119 	return 0;
120 }
121 
122 static int evdev_open(struct inode * inode, struct file * file)
123 {
124 	struct evdev_list *list;
125 	int i = iminor(inode) - EVDEV_MINOR_BASE;
126 	int accept_err;
127 
128 	if (i >= EVDEV_MINORS || !evdev_table[i] || !evdev_table[i]->exist)
129 		return -ENODEV;
130 
131 	if ((accept_err = input_accept_process(&(evdev_table[i]->handle), file)))
132 		return accept_err;
133 
134 	if (!(list = kmalloc(sizeof(struct evdev_list), GFP_KERNEL)))
135 		return -ENOMEM;
136 	memset(list, 0, sizeof(struct evdev_list));
137 
138 	list->evdev = evdev_table[i];
139 	list_add_tail(&list->node, &evdev_table[i]->list);
140 	file->private_data = list;
141 
142 	if (!list->evdev->open++)
143 		if (list->evdev->exist)
144 			input_open_device(&list->evdev->handle);
145 
146 	return 0;
147 }
148 
149 #ifdef CONFIG_COMPAT
150 struct input_event_compat {
151 	struct compat_timeval time;
152 	__u16 type;
153 	__u16 code;
154 	__s32 value;
155 };
156 
157 #ifdef CONFIG_X86_64
158 #  define COMPAT_TEST test_thread_flag(TIF_IA32)
159 #elif defined(CONFIG_IA64)
160 #  define COMPAT_TEST IS_IA32_PROCESS(ia64_task_regs(current))
161 #elif defined(CONFIG_ARCH_S390)
162 #  define COMPAT_TEST test_thread_flag(TIF_31BIT)
163 #else
164 #  define COMPAT_TEST test_thread_flag(TIF_32BIT)
165 #endif
166 
167 static ssize_t evdev_write_compat(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
168 {
169 	struct evdev_list *list = file->private_data;
170 	struct input_event_compat event;
171 	int retval = 0;
172 
173 	while (retval < count) {
174 		if (copy_from_user(&event, buffer + retval, sizeof(struct input_event_compat)))
175 			return -EFAULT;
176 		input_event(list->evdev->handle.dev, event.type, event.code, event.value);
177 		retval += sizeof(struct input_event_compat);
178 	}
179 
180 	return retval;
181 }
182 #endif
183 
184 static ssize_t evdev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
185 {
186 	struct evdev_list *list = file->private_data;
187 	struct input_event event;
188 	int retval = 0;
189 
190 	if (!list->evdev->exist) return -ENODEV;
191 
192 #ifdef CONFIG_COMPAT
193 	if (COMPAT_TEST)
194 		return evdev_write_compat(file, buffer, count, ppos);
195 #endif
196 
197 	while (retval < count) {
198 
199 		if (copy_from_user(&event, buffer + retval, sizeof(struct input_event)))
200 			return -EFAULT;
201 		input_event(list->evdev->handle.dev, event.type, event.code, event.value);
202 		retval += sizeof(struct input_event);
203 	}
204 
205 	return retval;
206 }
207 
208 #ifdef CONFIG_COMPAT
209 static ssize_t evdev_read_compat(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
210 {
211 	struct evdev_list *list = file->private_data;
212 	int retval;
213 
214 	if (count < sizeof(struct input_event_compat))
215 		return -EINVAL;
216 
217 	if (list->head == list->tail && list->evdev->exist && (file->f_flags & O_NONBLOCK))
218 		return -EAGAIN;
219 
220 	retval = wait_event_interruptible(list->evdev->wait,
221 		list->head != list->tail || (!list->evdev->exist));
222 
223 	if (retval)
224 		return retval;
225 
226 	if (!list->evdev->exist)
227 		return -ENODEV;
228 
229 	while (list->head != list->tail && retval + sizeof(struct input_event_compat) <= count) {
230 		struct input_event *event = (struct input_event *) list->buffer + list->tail;
231 		struct input_event_compat event_compat;
232 		event_compat.time.tv_sec = event->time.tv_sec;
233 		event_compat.time.tv_usec = event->time.tv_usec;
234 		event_compat.type = event->type;
235 		event_compat.code = event->code;
236 		event_compat.value = event->value;
237 
238 		if (copy_to_user(buffer + retval, &event_compat,
239 			sizeof(struct input_event_compat))) return -EFAULT;
240 		list->tail = (list->tail + 1) & (EVDEV_BUFFER_SIZE - 1);
241 		retval += sizeof(struct input_event_compat);
242 	}
243 
244 	return retval;
245 }
246 #endif
247 
248 static ssize_t evdev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
249 {
250 	struct evdev_list *list = file->private_data;
251 	int retval;
252 
253 #ifdef CONFIG_COMPAT
254 	if (COMPAT_TEST)
255 		return evdev_read_compat(file, buffer, count, ppos);
256 #endif
257 
258 	if (count < sizeof(struct input_event))
259 		return -EINVAL;
260 
261 	if (list->head == list->tail && list->evdev->exist && (file->f_flags & O_NONBLOCK))
262 		return -EAGAIN;
263 
264 	retval = wait_event_interruptible(list->evdev->wait,
265 		list->head != list->tail || (!list->evdev->exist));
266 
267 	if (retval)
268 		return retval;
269 
270 	if (!list->evdev->exist)
271 		return -ENODEV;
272 
273 	while (list->head != list->tail && retval + sizeof(struct input_event) <= count) {
274 		if (copy_to_user(buffer + retval, list->buffer + list->tail,
275 			sizeof(struct input_event))) return -EFAULT;
276 		list->tail = (list->tail + 1) & (EVDEV_BUFFER_SIZE - 1);
277 		retval += sizeof(struct input_event);
278 	}
279 
280 	return retval;
281 }
282 
283 /* No kernel lock - fine */
284 static unsigned int evdev_poll(struct file *file, poll_table *wait)
285 {
286 	struct evdev_list *list = file->private_data;
287 	poll_wait(file, &list->evdev->wait, wait);
288 	return ((list->head == list->tail) ? 0 : (POLLIN | POLLRDNORM)) |
289 		(list->evdev->exist ? 0 : (POLLHUP | POLLERR));
290 }
291 
292 static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
293 {
294 	struct evdev_list *list = file->private_data;
295 	struct evdev *evdev = list->evdev;
296 	struct input_dev *dev = evdev->handle.dev;
297 	struct input_absinfo abs;
298 	void __user *p = (void __user *)arg;
299 	int __user *ip = (int __user *)arg;
300 	int i, t, u, v;
301 
302 	if (!evdev->exist) return -ENODEV;
303 
304 	switch (cmd) {
305 
306 		case EVIOCGVERSION:
307 			return put_user(EV_VERSION, ip);
308 
309 		case EVIOCGID:
310 			return copy_to_user(p, &dev->id, sizeof(struct input_id)) ? -EFAULT : 0;
311 
312 		case EVIOCGKEYCODE:
313 			if (get_user(t, ip)) return -EFAULT;
314 			if (t < 0 || t >= dev->keycodemax || !dev->keycodesize) return -EINVAL;
315 			if (put_user(INPUT_KEYCODE(dev, t), ip + 1)) return -EFAULT;
316 			return 0;
317 
318 		case EVIOCSKEYCODE:
319 			if (get_user(t, ip)) return -EFAULT;
320 			if (t < 0 || t >= dev->keycodemax || !dev->keycodesize) return -EINVAL;
321 			if (get_user(v, ip + 1)) return -EFAULT;
322 			if (v < 0 || v > KEY_MAX) return -EINVAL;
323 			u = SET_INPUT_KEYCODE(dev, t, v);
324 			clear_bit(u, dev->keybit);
325 			set_bit(v, dev->keybit);
326 			for (i = 0; i < dev->keycodemax; i++)
327 				if (INPUT_KEYCODE(dev,i) == u)
328 					set_bit(u, dev->keybit);
329 			return 0;
330 
331 		case EVIOCSFF:
332 			if (dev->upload_effect) {
333 				struct ff_effect effect;
334 				int err;
335 
336 				if (copy_from_user(&effect, p, sizeof(effect)))
337 					return -EFAULT;
338 				err = dev->upload_effect(dev, &effect);
339 				if (put_user(effect.id, &(((struct ff_effect __user *)arg)->id)))
340 					return -EFAULT;
341 				return err;
342 			}
343 			else return -ENOSYS;
344 
345 		case EVIOCRMFF:
346 			if (dev->erase_effect) {
347 				return dev->erase_effect(dev, (int)arg);
348 			}
349 			else return -ENOSYS;
350 
351 		case EVIOCGEFFECTS:
352 			if (put_user(dev->ff_effects_max, ip))
353 				return -EFAULT;
354 			return 0;
355 
356 		case EVIOCGRAB:
357 			if (arg) {
358 				if (evdev->grab)
359 					return -EBUSY;
360 				if (input_grab_device(&evdev->handle))
361 					return -EBUSY;
362 				evdev->grab = list;
363 				return 0;
364 			} else {
365 				if (evdev->grab != list)
366 					return -EINVAL;
367 				input_release_device(&evdev->handle);
368 				evdev->grab = NULL;
369 				return 0;
370 			}
371 
372 		default:
373 
374 			if (_IOC_TYPE(cmd) != 'E')
375 				return -EINVAL;
376 
377 			if (_IOC_DIR(cmd) == _IOC_READ) {
378 
379 				if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0,0))) {
380 
381 					long *bits;
382 					int len;
383 
384 					switch (_IOC_NR(cmd) & EV_MAX) {
385 						case      0: bits = dev->evbit;  len = EV_MAX;  break;
386 						case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
387 						case EV_REL: bits = dev->relbit; len = REL_MAX; break;
388 						case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
389 						case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break;
390 						case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
391 						case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
392 						case EV_FF:  bits = dev->ffbit;  len = FF_MAX;  break;
393 						default: return -EINVAL;
394 					}
395 					len = NBITS(len) * sizeof(long);
396 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
397 					return copy_to_user(p, bits, len) ? -EFAULT : len;
398 				}
399 
400 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0))) {
401 					int len;
402 					len = NBITS(KEY_MAX) * sizeof(long);
403 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
404 					return copy_to_user(p, dev->key, len) ? -EFAULT : len;
405 				}
406 
407 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0))) {
408 					int len;
409 					len = NBITS(LED_MAX) * sizeof(long);
410 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
411 					return copy_to_user(p, dev->led, len) ? -EFAULT : len;
412 				}
413 
414 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0))) {
415 					int len;
416 					len = NBITS(SND_MAX) * sizeof(long);
417 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
418 					return copy_to_user(p, dev->snd, len) ? -EFAULT : len;
419 				}
420 
421 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0))) {
422 					int len;
423 					if (!dev->name) return -ENOENT;
424 					len = strlen(dev->name) + 1;
425 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
426 					return copy_to_user(p, dev->name, len) ? -EFAULT : len;
427 				}
428 
429 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0))) {
430 					int len;
431 					if (!dev->phys) return -ENOENT;
432 					len = strlen(dev->phys) + 1;
433 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
434 					return copy_to_user(p, dev->phys, len) ? -EFAULT : len;
435 				}
436 
437 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0))) {
438 					int len;
439 					if (!dev->uniq) return -ENOENT;
440 					len = strlen(dev->uniq) + 1;
441 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
442 					return copy_to_user(p, dev->uniq, len) ? -EFAULT : len;
443 				}
444 
445 				if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
446 
447 					int t = _IOC_NR(cmd) & ABS_MAX;
448 
449 					abs.value = dev->abs[t];
450 					abs.minimum = dev->absmin[t];
451 					abs.maximum = dev->absmax[t];
452 					abs.fuzz = dev->absfuzz[t];
453 					abs.flat = dev->absflat[t];
454 
455 					if (copy_to_user(p, &abs, sizeof(struct input_absinfo)))
456 						return -EFAULT;
457 
458 					return 0;
459 				}
460 
461 			}
462 
463 			if (_IOC_DIR(cmd) == _IOC_WRITE) {
464 
465 				if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
466 
467 					int t = _IOC_NR(cmd) & ABS_MAX;
468 
469 					if (copy_from_user(&abs, p, sizeof(struct input_absinfo)))
470 						return -EFAULT;
471 
472 					dev->abs[t] = abs.value;
473 					dev->absmin[t] = abs.minimum;
474 					dev->absmax[t] = abs.maximum;
475 					dev->absfuzz[t] = abs.fuzz;
476 					dev->absflat[t] = abs.flat;
477 
478 					return 0;
479 				}
480 			}
481 	}
482 	return -EINVAL;
483 }
484 
485 #ifdef CONFIG_COMPAT
486 
487 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
488 #define NBITS_COMPAT(x) ((((x)-1)/BITS_PER_LONG_COMPAT)+1)
489 #define OFF_COMPAT(x)  ((x)%BITS_PER_LONG_COMPAT)
490 #define BIT_COMPAT(x)  (1UL<<OFF_COMPAT(x))
491 #define LONG_COMPAT(x) ((x)/BITS_PER_LONG_COMPAT)
492 #define test_bit_compat(bit, array) ((array[LONG_COMPAT(bit)] >> OFF_COMPAT(bit)) & 1)
493 
494 #ifdef __BIG_ENDIAN
495 #define bit_to_user(bit, max) \
496 do { \
497 	int i; \
498 	int len = NBITS_COMPAT((max)) * sizeof(compat_long_t); \
499 	if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd); \
500 	for (i = 0; i < len / sizeof(compat_long_t); i++) \
501 		if (copy_to_user((compat_long_t*) p + i, \
502 				 (compat_long_t*) (bit) + i + 1 - ((i % 2) << 1), \
503 				 sizeof(compat_long_t))) \
504 			return -EFAULT; \
505 	return len; \
506 } while (0)
507 #else
508 #define bit_to_user(bit, max) \
509 do { \
510 	int len = NBITS_COMPAT((max)) * sizeof(compat_long_t); \
511 	if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd); \
512 	return copy_to_user(p, (bit), len) ? -EFAULT : len; \
513 } while (0)
514 #endif
515 
516 static long evdev_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
517 {
518 	struct evdev_list *list = file->private_data;
519 	struct evdev *evdev = list->evdev;
520 	struct input_dev *dev = evdev->handle.dev;
521 	struct input_absinfo abs;
522 	void __user *p = compat_ptr(arg);
523 
524 	if (!evdev->exist) return -ENODEV;
525 
526 	switch (cmd) {
527 
528 		case EVIOCGVERSION:
529 		case EVIOCGID:
530 		case EVIOCGKEYCODE:
531 		case EVIOCSKEYCODE:
532 		case EVIOCSFF:
533 		case EVIOCRMFF:
534 		case EVIOCGEFFECTS:
535 		case EVIOCGRAB:
536 			return evdev_ioctl(file, cmd, (unsigned long) p);
537 
538 		default:
539 
540 			if (_IOC_TYPE(cmd) != 'E')
541 				return -EINVAL;
542 
543 			if (_IOC_DIR(cmd) == _IOC_READ) {
544 
545 				if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0,0))) {
546 					long *bits;
547 					int max;
548 
549 					switch (_IOC_NR(cmd) & EV_MAX) {
550 						case      0: bits = dev->evbit;  max = EV_MAX;  break;
551 						case EV_KEY: bits = dev->keybit; max = KEY_MAX; break;
552 						case EV_REL: bits = dev->relbit; max = REL_MAX; break;
553 						case EV_ABS: bits = dev->absbit; max = ABS_MAX; break;
554 						case EV_MSC: bits = dev->mscbit; max = MSC_MAX; break;
555 						case EV_LED: bits = dev->ledbit; max = LED_MAX; break;
556 						case EV_SND: bits = dev->sndbit; max = SND_MAX; break;
557 						case EV_FF:  bits = dev->ffbit;  max = FF_MAX;  break;
558 						default: return -EINVAL;
559 					}
560 					bit_to_user(bits, max);
561 				}
562 
563 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0)))
564 					bit_to_user(dev->key, KEY_MAX);
565 
566 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0)))
567 					bit_to_user(dev->led, LED_MAX);
568 
569 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0)))
570 					bit_to_user(dev->snd, SND_MAX);
571 
572 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0))) {
573 					int len;
574 					if (!dev->name) return -ENOENT;
575 					len = strlen(dev->name) + 1;
576 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
577 					return copy_to_user(p, dev->name, len) ? -EFAULT : len;
578 				}
579 
580 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0))) {
581 					int len;
582 					if (!dev->phys) return -ENOENT;
583 					len = strlen(dev->phys) + 1;
584 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
585 					return copy_to_user(p, dev->phys, len) ? -EFAULT : len;
586 				}
587 
588 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0))) {
589 					int len;
590 					if (!dev->uniq) return -ENOENT;
591 					len = strlen(dev->uniq) + 1;
592 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
593 					return copy_to_user(p, dev->uniq, len) ? -EFAULT : len;
594 				}
595 
596 				if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
597 
598 					int t = _IOC_NR(cmd) & ABS_MAX;
599 
600 					abs.value = dev->abs[t];
601 					abs.minimum = dev->absmin[t];
602 					abs.maximum = dev->absmax[t];
603 					abs.fuzz = dev->absfuzz[t];
604 					abs.flat = dev->absflat[t];
605 
606 					if (copy_to_user(p, &abs, sizeof(struct input_absinfo)))
607 						return -EFAULT;
608 
609 					return 0;
610 				}
611 			}
612 
613 			if (_IOC_DIR(cmd) == _IOC_WRITE) {
614 
615 				if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
616 
617 					int t = _IOC_NR(cmd) & ABS_MAX;
618 
619 					if (copy_from_user(&abs, p, sizeof(struct input_absinfo)))
620 						return -EFAULT;
621 
622 					dev->abs[t] = abs.value;
623 					dev->absmin[t] = abs.minimum;
624 					dev->absmax[t] = abs.maximum;
625 					dev->absfuzz[t] = abs.fuzz;
626 					dev->absflat[t] = abs.flat;
627 
628 					return 0;
629 				}
630 			}
631 	}
632 	return -EINVAL;
633 }
634 #endif
635 
636 static struct file_operations evdev_fops = {
637 	.owner =	THIS_MODULE,
638 	.read =		evdev_read,
639 	.write =	evdev_write,
640 	.poll =		evdev_poll,
641 	.open =		evdev_open,
642 	.release =	evdev_release,
643 	.unlocked_ioctl = evdev_ioctl,
644 #ifdef CONFIG_COMPAT
645 	.compat_ioctl =	evdev_ioctl_compat,
646 #endif
647 	.fasync =	evdev_fasync,
648 	.flush =	evdev_flush
649 };
650 
651 static struct input_handle *evdev_connect(struct input_handler *handler, struct input_dev *dev, struct input_device_id *id)
652 {
653 	struct evdev *evdev;
654 	int minor;
655 
656 	for (minor = 0; minor < EVDEV_MINORS && evdev_table[minor]; minor++);
657 	if (minor == EVDEV_MINORS) {
658 		printk(KERN_ERR "evdev: no more free evdev devices\n");
659 		return NULL;
660 	}
661 
662 	if (!(evdev = kmalloc(sizeof(struct evdev), GFP_KERNEL)))
663 		return NULL;
664 	memset(evdev, 0, sizeof(struct evdev));
665 
666 	INIT_LIST_HEAD(&evdev->list);
667 	init_waitqueue_head(&evdev->wait);
668 
669 	evdev->exist = 1;
670 	evdev->minor = minor;
671 	evdev->handle.dev = dev;
672 	evdev->handle.name = evdev->name;
673 	evdev->handle.handler = handler;
674 	evdev->handle.private = evdev;
675 	sprintf(evdev->name, "event%d", minor);
676 
677 	evdev_table[minor] = evdev;
678 
679 	devfs_mk_cdev(MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor),
680 			S_IFCHR|S_IRUGO|S_IWUSR, "input/event%d", minor);
681 	class_device_create(input_class,
682 			MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor),
683 			dev->dev, "event%d", minor);
684 
685 	return &evdev->handle;
686 }
687 
688 static void evdev_disconnect(struct input_handle *handle)
689 {
690 	struct evdev *evdev = handle->private;
691 	struct evdev_list *list;
692 
693 	class_device_destroy(input_class,
694 			MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + evdev->minor));
695 	devfs_remove("input/event%d", evdev->minor);
696 	evdev->exist = 0;
697 
698 	if (evdev->open) {
699 		input_close_device(handle);
700 		wake_up_interruptible(&evdev->wait);
701 		list_for_each_entry(list, &evdev->list, node)
702 			kill_fasync(&list->fasync, SIGIO, POLL_HUP);
703 	} else
704 		evdev_free(evdev);
705 }
706 
707 static struct input_device_id evdev_ids[] = {
708 	{ .driver_info = 1 },	/* Matches all devices */
709 	{ },			/* Terminating zero entry */
710 };
711 
712 MODULE_DEVICE_TABLE(input, evdev_ids);
713 
714 static struct input_handler evdev_handler = {
715 	.event =	evdev_event,
716 	.connect =	evdev_connect,
717 	.disconnect =	evdev_disconnect,
718 	.fops =		&evdev_fops,
719 	.minor =	EVDEV_MINOR_BASE,
720 	.name =		"evdev",
721 	.id_table =	evdev_ids,
722 };
723 
724 static int __init evdev_init(void)
725 {
726 	input_register_handler(&evdev_handler);
727 	return 0;
728 }
729 
730 static void __exit evdev_exit(void)
731 {
732 	input_unregister_handler(&evdev_handler);
733 }
734 
735 module_init(evdev_init);
736 module_exit(evdev_exit);
737 
738 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
739 MODULE_DESCRIPTION("Input driver event char devices");
740 MODULE_LICENSE("GPL");
741