xref: /linux/drivers/input/evdev.c (revision 13abf8130139c2ccd4962a7e5a8902be5e6cb5a7)
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 #elif defined(CONFIG_MIPS)
164 #  define COMPAT_TEST (current->thread.mflags & MF_32BIT_ADDR)
165 #else
166 #  define COMPAT_TEST test_thread_flag(TIF_32BIT)
167 #endif
168 
169 static ssize_t evdev_write_compat(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
170 {
171 	struct evdev_list *list = file->private_data;
172 	struct input_event_compat event;
173 	int retval = 0;
174 
175 	while (retval < count) {
176 		if (copy_from_user(&event, buffer + retval, sizeof(struct input_event_compat)))
177 			return -EFAULT;
178 		input_event(list->evdev->handle.dev, event.type, event.code, event.value);
179 		retval += sizeof(struct input_event_compat);
180 	}
181 
182 	return retval;
183 }
184 #endif
185 
186 static ssize_t evdev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
187 {
188 	struct evdev_list *list = file->private_data;
189 	struct input_event event;
190 	int retval = 0;
191 
192 	if (!list->evdev->exist) return -ENODEV;
193 
194 #ifdef CONFIG_COMPAT
195 	if (COMPAT_TEST)
196 		return evdev_write_compat(file, buffer, count, ppos);
197 #endif
198 
199 	while (retval < count) {
200 
201 		if (copy_from_user(&event, buffer + retval, sizeof(struct input_event)))
202 			return -EFAULT;
203 		input_event(list->evdev->handle.dev, event.type, event.code, event.value);
204 		retval += sizeof(struct input_event);
205 	}
206 
207 	return retval;
208 }
209 
210 #ifdef CONFIG_COMPAT
211 static ssize_t evdev_read_compat(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
212 {
213 	struct evdev_list *list = file->private_data;
214 	int retval;
215 
216 	if (count < sizeof(struct input_event_compat))
217 		return -EINVAL;
218 
219 	if (list->head == list->tail && list->evdev->exist && (file->f_flags & O_NONBLOCK))
220 		return -EAGAIN;
221 
222 	retval = wait_event_interruptible(list->evdev->wait,
223 		list->head != list->tail || (!list->evdev->exist));
224 
225 	if (retval)
226 		return retval;
227 
228 	if (!list->evdev->exist)
229 		return -ENODEV;
230 
231 	while (list->head != list->tail && retval + sizeof(struct input_event_compat) <= count) {
232 		struct input_event *event = (struct input_event *) list->buffer + list->tail;
233 		struct input_event_compat event_compat;
234 		event_compat.time.tv_sec = event->time.tv_sec;
235 		event_compat.time.tv_usec = event->time.tv_usec;
236 		event_compat.type = event->type;
237 		event_compat.code = event->code;
238 		event_compat.value = event->value;
239 
240 		if (copy_to_user(buffer + retval, &event_compat,
241 			sizeof(struct input_event_compat))) return -EFAULT;
242 		list->tail = (list->tail + 1) & (EVDEV_BUFFER_SIZE - 1);
243 		retval += sizeof(struct input_event_compat);
244 	}
245 
246 	return retval;
247 }
248 #endif
249 
250 static ssize_t evdev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
251 {
252 	struct evdev_list *list = file->private_data;
253 	int retval;
254 
255 #ifdef CONFIG_COMPAT
256 	if (COMPAT_TEST)
257 		return evdev_read_compat(file, buffer, count, ppos);
258 #endif
259 
260 	if (count < sizeof(struct input_event))
261 		return -EINVAL;
262 
263 	if (list->head == list->tail && list->evdev->exist && (file->f_flags & O_NONBLOCK))
264 		return -EAGAIN;
265 
266 	retval = wait_event_interruptible(list->evdev->wait,
267 		list->head != list->tail || (!list->evdev->exist));
268 
269 	if (retval)
270 		return retval;
271 
272 	if (!list->evdev->exist)
273 		return -ENODEV;
274 
275 	while (list->head != list->tail && retval + sizeof(struct input_event) <= count) {
276 		if (copy_to_user(buffer + retval, list->buffer + list->tail,
277 			sizeof(struct input_event))) return -EFAULT;
278 		list->tail = (list->tail + 1) & (EVDEV_BUFFER_SIZE - 1);
279 		retval += sizeof(struct input_event);
280 	}
281 
282 	return retval;
283 }
284 
285 /* No kernel lock - fine */
286 static unsigned int evdev_poll(struct file *file, poll_table *wait)
287 {
288 	struct evdev_list *list = file->private_data;
289 	poll_wait(file, &list->evdev->wait, wait);
290 	return ((list->head == list->tail) ? 0 : (POLLIN | POLLRDNORM)) |
291 		(list->evdev->exist ? 0 : (POLLHUP | POLLERR));
292 }
293 
294 static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
295 {
296 	struct evdev_list *list = file->private_data;
297 	struct evdev *evdev = list->evdev;
298 	struct input_dev *dev = evdev->handle.dev;
299 	struct input_absinfo abs;
300 	void __user *p = (void __user *)arg;
301 	int __user *ip = (int __user *)arg;
302 	int i, t, u, v;
303 
304 	if (!evdev->exist) return -ENODEV;
305 
306 	switch (cmd) {
307 
308 		case EVIOCGVERSION:
309 			return put_user(EV_VERSION, ip);
310 
311 		case EVIOCGID:
312 			return copy_to_user(p, &dev->id, sizeof(struct input_id)) ? -EFAULT : 0;
313 
314 		case EVIOCGKEYCODE:
315 			if (get_user(t, ip)) return -EFAULT;
316 			if (t < 0 || t >= dev->keycodemax || !dev->keycodesize) return -EINVAL;
317 			if (put_user(INPUT_KEYCODE(dev, t), ip + 1)) return -EFAULT;
318 			return 0;
319 
320 		case EVIOCSKEYCODE:
321 			if (get_user(t, ip)) return -EFAULT;
322 			if (t < 0 || t >= dev->keycodemax || !dev->keycodesize) return -EINVAL;
323 			if (get_user(v, ip + 1)) return -EFAULT;
324 			if (v < 0 || v > KEY_MAX) return -EINVAL;
325 			if (v >> (dev->keycodesize * 8)) return -EINVAL;
326 			u = SET_INPUT_KEYCODE(dev, t, v);
327 			clear_bit(u, dev->keybit);
328 			set_bit(v, dev->keybit);
329 			for (i = 0; i < dev->keycodemax; i++)
330 				if (INPUT_KEYCODE(dev,i) == u)
331 					set_bit(u, dev->keybit);
332 			return 0;
333 
334 		case EVIOCSFF:
335 			if (dev->upload_effect) {
336 				struct ff_effect effect;
337 				int err;
338 
339 				if (copy_from_user(&effect, p, sizeof(effect)))
340 					return -EFAULT;
341 				err = dev->upload_effect(dev, &effect);
342 				if (put_user(effect.id, &(((struct ff_effect __user *)arg)->id)))
343 					return -EFAULT;
344 				return err;
345 			}
346 			else return -ENOSYS;
347 
348 		case EVIOCRMFF:
349 			if (dev->erase_effect) {
350 				return dev->erase_effect(dev, (int)arg);
351 			}
352 			else return -ENOSYS;
353 
354 		case EVIOCGEFFECTS:
355 			if (put_user(dev->ff_effects_max, ip))
356 				return -EFAULT;
357 			return 0;
358 
359 		case EVIOCGRAB:
360 			if (arg) {
361 				if (evdev->grab)
362 					return -EBUSY;
363 				if (input_grab_device(&evdev->handle))
364 					return -EBUSY;
365 				evdev->grab = list;
366 				return 0;
367 			} else {
368 				if (evdev->grab != list)
369 					return -EINVAL;
370 				input_release_device(&evdev->handle);
371 				evdev->grab = NULL;
372 				return 0;
373 			}
374 
375 		default:
376 
377 			if (_IOC_TYPE(cmd) != 'E')
378 				return -EINVAL;
379 
380 			if (_IOC_DIR(cmd) == _IOC_READ) {
381 
382 				if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0,0))) {
383 
384 					long *bits;
385 					int len;
386 
387 					switch (_IOC_NR(cmd) & EV_MAX) {
388 						case      0: bits = dev->evbit;  len = EV_MAX;  break;
389 						case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
390 						case EV_REL: bits = dev->relbit; len = REL_MAX; break;
391 						case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
392 						case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break;
393 						case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
394 						case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
395 						case EV_FF:  bits = dev->ffbit;  len = FF_MAX;  break;
396 						default: return -EINVAL;
397 					}
398 					len = NBITS(len) * sizeof(long);
399 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
400 					return copy_to_user(p, bits, len) ? -EFAULT : len;
401 				}
402 
403 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0))) {
404 					int len;
405 					len = NBITS(KEY_MAX) * sizeof(long);
406 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
407 					return copy_to_user(p, dev->key, len) ? -EFAULT : len;
408 				}
409 
410 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0))) {
411 					int len;
412 					len = NBITS(LED_MAX) * sizeof(long);
413 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
414 					return copy_to_user(p, dev->led, len) ? -EFAULT : len;
415 				}
416 
417 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0))) {
418 					int len;
419 					len = NBITS(SND_MAX) * sizeof(long);
420 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
421 					return copy_to_user(p, dev->snd, len) ? -EFAULT : len;
422 				}
423 
424 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0))) {
425 					int len;
426 					if (!dev->name) return -ENOENT;
427 					len = strlen(dev->name) + 1;
428 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
429 					return copy_to_user(p, dev->name, len) ? -EFAULT : len;
430 				}
431 
432 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0))) {
433 					int len;
434 					if (!dev->phys) return -ENOENT;
435 					len = strlen(dev->phys) + 1;
436 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
437 					return copy_to_user(p, dev->phys, len) ? -EFAULT : len;
438 				}
439 
440 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0))) {
441 					int len;
442 					if (!dev->uniq) return -ENOENT;
443 					len = strlen(dev->uniq) + 1;
444 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
445 					return copy_to_user(p, dev->uniq, len) ? -EFAULT : len;
446 				}
447 
448 				if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
449 
450 					int t = _IOC_NR(cmd) & ABS_MAX;
451 
452 					abs.value = dev->abs[t];
453 					abs.minimum = dev->absmin[t];
454 					abs.maximum = dev->absmax[t];
455 					abs.fuzz = dev->absfuzz[t];
456 					abs.flat = dev->absflat[t];
457 
458 					if (copy_to_user(p, &abs, sizeof(struct input_absinfo)))
459 						return -EFAULT;
460 
461 					return 0;
462 				}
463 
464 			}
465 
466 			if (_IOC_DIR(cmd) == _IOC_WRITE) {
467 
468 				if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
469 
470 					int t = _IOC_NR(cmd) & ABS_MAX;
471 
472 					if (copy_from_user(&abs, p, sizeof(struct input_absinfo)))
473 						return -EFAULT;
474 
475 					dev->abs[t] = abs.value;
476 					dev->absmin[t] = abs.minimum;
477 					dev->absmax[t] = abs.maximum;
478 					dev->absfuzz[t] = abs.fuzz;
479 					dev->absflat[t] = abs.flat;
480 
481 					return 0;
482 				}
483 			}
484 	}
485 	return -EINVAL;
486 }
487 
488 #ifdef CONFIG_COMPAT
489 
490 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
491 #define NBITS_COMPAT(x) ((((x)-1)/BITS_PER_LONG_COMPAT)+1)
492 #define OFF_COMPAT(x)  ((x)%BITS_PER_LONG_COMPAT)
493 #define BIT_COMPAT(x)  (1UL<<OFF_COMPAT(x))
494 #define LONG_COMPAT(x) ((x)/BITS_PER_LONG_COMPAT)
495 #define test_bit_compat(bit, array) ((array[LONG_COMPAT(bit)] >> OFF_COMPAT(bit)) & 1)
496 
497 #ifdef __BIG_ENDIAN
498 #define bit_to_user(bit, max) \
499 do { \
500 	int i; \
501 	int len = NBITS_COMPAT((max)) * sizeof(compat_long_t); \
502 	if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd); \
503 	for (i = 0; i < len / sizeof(compat_long_t); i++) \
504 		if (copy_to_user((compat_long_t*) p + i, \
505 				 (compat_long_t*) (bit) + i + 1 - ((i % 2) << 1), \
506 				 sizeof(compat_long_t))) \
507 			return -EFAULT; \
508 	return len; \
509 } while (0)
510 #else
511 #define bit_to_user(bit, max) \
512 do { \
513 	int len = NBITS_COMPAT((max)) * sizeof(compat_long_t); \
514 	if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd); \
515 	return copy_to_user(p, (bit), len) ? -EFAULT : len; \
516 } while (0)
517 #endif
518 
519 static long evdev_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
520 {
521 	struct evdev_list *list = file->private_data;
522 	struct evdev *evdev = list->evdev;
523 	struct input_dev *dev = evdev->handle.dev;
524 	struct input_absinfo abs;
525 	void __user *p = compat_ptr(arg);
526 
527 	if (!evdev->exist) return -ENODEV;
528 
529 	switch (cmd) {
530 
531 		case EVIOCGVERSION:
532 		case EVIOCGID:
533 		case EVIOCGKEYCODE:
534 		case EVIOCSKEYCODE:
535 		case EVIOCSFF:
536 		case EVIOCRMFF:
537 		case EVIOCGEFFECTS:
538 		case EVIOCGRAB:
539 			return evdev_ioctl(file, cmd, (unsigned long) p);
540 
541 		default:
542 
543 			if (_IOC_TYPE(cmd) != 'E')
544 				return -EINVAL;
545 
546 			if (_IOC_DIR(cmd) == _IOC_READ) {
547 
548 				if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0,0))) {
549 					long *bits;
550 					int max;
551 
552 					switch (_IOC_NR(cmd) & EV_MAX) {
553 						case      0: bits = dev->evbit;  max = EV_MAX;  break;
554 						case EV_KEY: bits = dev->keybit; max = KEY_MAX; break;
555 						case EV_REL: bits = dev->relbit; max = REL_MAX; break;
556 						case EV_ABS: bits = dev->absbit; max = ABS_MAX; break;
557 						case EV_MSC: bits = dev->mscbit; max = MSC_MAX; break;
558 						case EV_LED: bits = dev->ledbit; max = LED_MAX; break;
559 						case EV_SND: bits = dev->sndbit; max = SND_MAX; break;
560 						case EV_FF:  bits = dev->ffbit;  max = FF_MAX;  break;
561 						default: return -EINVAL;
562 					}
563 					bit_to_user(bits, max);
564 				}
565 
566 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0)))
567 					bit_to_user(dev->key, KEY_MAX);
568 
569 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0)))
570 					bit_to_user(dev->led, LED_MAX);
571 
572 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0)))
573 					bit_to_user(dev->snd, SND_MAX);
574 
575 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0))) {
576 					int len;
577 					if (!dev->name) return -ENOENT;
578 					len = strlen(dev->name) + 1;
579 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
580 					return copy_to_user(p, dev->name, len) ? -EFAULT : len;
581 				}
582 
583 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0))) {
584 					int len;
585 					if (!dev->phys) return -ENOENT;
586 					len = strlen(dev->phys) + 1;
587 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
588 					return copy_to_user(p, dev->phys, len) ? -EFAULT : len;
589 				}
590 
591 				if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0))) {
592 					int len;
593 					if (!dev->uniq) return -ENOENT;
594 					len = strlen(dev->uniq) + 1;
595 					if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
596 					return copy_to_user(p, dev->uniq, len) ? -EFAULT : len;
597 				}
598 
599 				if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
600 
601 					int t = _IOC_NR(cmd) & ABS_MAX;
602 
603 					abs.value = dev->abs[t];
604 					abs.minimum = dev->absmin[t];
605 					abs.maximum = dev->absmax[t];
606 					abs.fuzz = dev->absfuzz[t];
607 					abs.flat = dev->absflat[t];
608 
609 					if (copy_to_user(p, &abs, sizeof(struct input_absinfo)))
610 						return -EFAULT;
611 
612 					return 0;
613 				}
614 			}
615 
616 			if (_IOC_DIR(cmd) == _IOC_WRITE) {
617 
618 				if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
619 
620 					int t = _IOC_NR(cmd) & ABS_MAX;
621 
622 					if (copy_from_user(&abs, p, sizeof(struct input_absinfo)))
623 						return -EFAULT;
624 
625 					dev->abs[t] = abs.value;
626 					dev->absmin[t] = abs.minimum;
627 					dev->absmax[t] = abs.maximum;
628 					dev->absfuzz[t] = abs.fuzz;
629 					dev->absflat[t] = abs.flat;
630 
631 					return 0;
632 				}
633 			}
634 	}
635 	return -EINVAL;
636 }
637 #endif
638 
639 static struct file_operations evdev_fops = {
640 	.owner =	THIS_MODULE,
641 	.read =		evdev_read,
642 	.write =	evdev_write,
643 	.poll =		evdev_poll,
644 	.open =		evdev_open,
645 	.release =	evdev_release,
646 	.unlocked_ioctl = evdev_ioctl,
647 #ifdef CONFIG_COMPAT
648 	.compat_ioctl =	evdev_ioctl_compat,
649 #endif
650 	.fasync =	evdev_fasync,
651 	.flush =	evdev_flush
652 };
653 
654 static struct input_handle *evdev_connect(struct input_handler *handler, struct input_dev *dev, struct input_device_id *id)
655 {
656 	struct evdev *evdev;
657 	int minor;
658 
659 	for (minor = 0; minor < EVDEV_MINORS && evdev_table[minor]; minor++);
660 	if (minor == EVDEV_MINORS) {
661 		printk(KERN_ERR "evdev: no more free evdev devices\n");
662 		return NULL;
663 	}
664 
665 	if (!(evdev = kmalloc(sizeof(struct evdev), GFP_KERNEL)))
666 		return NULL;
667 	memset(evdev, 0, sizeof(struct evdev));
668 
669 	INIT_LIST_HEAD(&evdev->list);
670 	init_waitqueue_head(&evdev->wait);
671 
672 	evdev->exist = 1;
673 	evdev->minor = minor;
674 	evdev->handle.dev = dev;
675 	evdev->handle.name = evdev->name;
676 	evdev->handle.handler = handler;
677 	evdev->handle.private = evdev;
678 	sprintf(evdev->name, "event%d", minor);
679 
680 	evdev_table[minor] = evdev;
681 
682 	devfs_mk_cdev(MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor),
683 			S_IFCHR|S_IRUGO|S_IWUSR, "input/event%d", minor);
684 	class_device_create(input_class,
685 			MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor),
686 			dev->dev, "event%d", minor);
687 
688 	return &evdev->handle;
689 }
690 
691 static void evdev_disconnect(struct input_handle *handle)
692 {
693 	struct evdev *evdev = handle->private;
694 	struct evdev_list *list;
695 
696 	class_device_destroy(input_class,
697 			MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + evdev->minor));
698 	devfs_remove("input/event%d", evdev->minor);
699 	evdev->exist = 0;
700 
701 	if (evdev->open) {
702 		input_close_device(handle);
703 		wake_up_interruptible(&evdev->wait);
704 		list_for_each_entry(list, &evdev->list, node)
705 			kill_fasync(&list->fasync, SIGIO, POLL_HUP);
706 	} else
707 		evdev_free(evdev);
708 }
709 
710 static struct input_device_id evdev_ids[] = {
711 	{ .driver_info = 1 },	/* Matches all devices */
712 	{ },			/* Terminating zero entry */
713 };
714 
715 MODULE_DEVICE_TABLE(input, evdev_ids);
716 
717 static struct input_handler evdev_handler = {
718 	.event =	evdev_event,
719 	.connect =	evdev_connect,
720 	.disconnect =	evdev_disconnect,
721 	.fops =		&evdev_fops,
722 	.minor =	EVDEV_MINOR_BASE,
723 	.name =		"evdev",
724 	.id_table =	evdev_ids,
725 };
726 
727 static int __init evdev_init(void)
728 {
729 	input_register_handler(&evdev_handler);
730 	return 0;
731 }
732 
733 static void __exit evdev_exit(void)
734 {
735 	input_unregister_handler(&evdev_handler);
736 }
737 
738 module_init(evdev_init);
739 module_exit(evdev_exit);
740 
741 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
742 MODULE_DESCRIPTION("Input driver event char devices");
743 MODULE_LICENSE("GPL");
744