Input: reduce raciness when input handlers disconnect
[linux-2.6.git] / drivers / input / evdev.c
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/compat.h>
24
25 struct evdev {
26         int exist;
27         int open;
28         int minor;
29         char name[16];
30         struct input_handle handle;
31         wait_queue_head_t wait;
32         struct evdev_client *grab;
33         struct list_head client_list;
34 };
35
36 struct evdev_client {
37         struct input_event buffer[EVDEV_BUFFER_SIZE];
38         int head;
39         int tail;
40         struct fasync_struct *fasync;
41         struct evdev *evdev;
42         struct list_head node;
43 };
44
45 static struct evdev *evdev_table[EVDEV_MINORS];
46
47 static void evdev_event(struct input_handle *handle, unsigned int type, unsigned int code, int value)
48 {
49         struct evdev *evdev = handle->private;
50         struct evdev_client *client;
51
52         if (evdev->grab) {
53                 client = evdev->grab;
54
55                 do_gettimeofday(&client->buffer[client->head].time);
56                 client->buffer[client->head].type = type;
57                 client->buffer[client->head].code = code;
58                 client->buffer[client->head].value = value;
59                 client->head = (client->head + 1) & (EVDEV_BUFFER_SIZE - 1);
60
61                 kill_fasync(&client->fasync, SIGIO, POLL_IN);
62         } else
63                 list_for_each_entry(client, &evdev->client_list, node) {
64
65                         do_gettimeofday(&client->buffer[client->head].time);
66                         client->buffer[client->head].type = type;
67                         client->buffer[client->head].code = code;
68                         client->buffer[client->head].value = value;
69                         client->head = (client->head + 1) & (EVDEV_BUFFER_SIZE - 1);
70
71                         kill_fasync(&client->fasync, SIGIO, POLL_IN);
72                 }
73
74         wake_up_interruptible(&evdev->wait);
75 }
76
77 static int evdev_fasync(int fd, struct file *file, int on)
78 {
79         struct evdev_client *client = file->private_data;
80         int retval;
81
82         retval = fasync_helper(fd, file, on, &client->fasync);
83
84         return retval < 0 ? retval : 0;
85 }
86
87 static int evdev_flush(struct file *file, fl_owner_t id)
88 {
89         struct evdev_client *client = file->private_data;
90         struct evdev *evdev = client->evdev;
91
92         if (!evdev->exist)
93                 return -ENODEV;
94
95         return input_flush_device(&evdev->handle, file);
96 }
97
98 static void evdev_free(struct evdev *evdev)
99 {
100         evdev_table[evdev->minor] = NULL;
101         kfree(evdev);
102 }
103
104 static int evdev_release(struct inode *inode, struct file *file)
105 {
106         struct evdev_client *client = file->private_data;
107         struct evdev *evdev = client->evdev;
108
109         if (evdev->grab == client) {
110                 input_release_device(&evdev->handle);
111                 evdev->grab = NULL;
112         }
113
114         evdev_fasync(-1, file, 0);
115         list_del(&client->node);
116         kfree(client);
117
118         if (!--evdev->open) {
119                 if (evdev->exist)
120                         input_close_device(&evdev->handle);
121                 else
122                         evdev_free(evdev);
123         }
124
125         return 0;
126 }
127
128 static int evdev_open(struct inode *inode, struct file *file)
129 {
130         struct evdev_client *client;
131         struct evdev *evdev;
132         int i = iminor(inode) - EVDEV_MINOR_BASE;
133         int error;
134
135         if (i >= EVDEV_MINORS)
136                 return -ENODEV;
137
138         evdev = evdev_table[i];
139
140         if (!evdev || !evdev->exist)
141                 return -ENODEV;
142
143         client = kzalloc(sizeof(struct evdev_client), GFP_KERNEL);
144         if (!client)
145                 return -ENOMEM;
146
147         client->evdev = evdev;
148         list_add_tail(&client->node, &evdev->client_list);
149
150         if (!evdev->open++ && evdev->exist) {
151                 error = input_open_device(&evdev->handle);
152                 if (error) {
153                         list_del(&client->node);
154                         kfree(client);
155                         return error;
156                 }
157         }
158
159         file->private_data = client;
160         return 0;
161 }
162
163 #ifdef CONFIG_COMPAT
164
165 struct input_event_compat {
166         struct compat_timeval time;
167         __u16 type;
168         __u16 code;
169         __s32 value;
170 };
171
172 /* Note to the author of this code: did it ever occur to
173    you why the ifdefs are needed? Think about it again. -AK */
174 #ifdef CONFIG_X86_64
175 #  define COMPAT_TEST is_compat_task()
176 #elif defined(CONFIG_IA64)
177 #  define COMPAT_TEST IS_IA32_PROCESS(task_pt_regs(current))
178 #elif defined(CONFIG_S390)
179 #  define COMPAT_TEST test_thread_flag(TIF_31BIT)
180 #elif defined(CONFIG_MIPS)
181 #  define COMPAT_TEST (current->thread.mflags & MF_32BIT_ADDR)
182 #else
183 #  define COMPAT_TEST test_thread_flag(TIF_32BIT)
184 #endif
185
186 static inline size_t evdev_event_size(void)
187 {
188         return COMPAT_TEST ?
189                 sizeof(struct input_event_compat) : sizeof(struct input_event);
190 }
191
192 static int evdev_event_from_user(const char __user *buffer, struct input_event *event)
193 {
194         if (COMPAT_TEST) {
195                 struct input_event_compat compat_event;
196
197                 if (copy_from_user(&compat_event, buffer, sizeof(struct input_event_compat)))
198                         return -EFAULT;
199
200                 event->time.tv_sec = compat_event.time.tv_sec;
201                 event->time.tv_usec = compat_event.time.tv_usec;
202                 event->type = compat_event.type;
203                 event->code = compat_event.code;
204                 event->value = compat_event.value;
205
206         } else {
207                 if (copy_from_user(event, buffer, sizeof(struct input_event)))
208                         return -EFAULT;
209         }
210
211         return 0;
212 }
213
214 static int evdev_event_to_user(char __user *buffer, const struct input_event *event)
215 {
216         if (COMPAT_TEST) {
217                 struct input_event_compat compat_event;
218
219                 compat_event.time.tv_sec = event->time.tv_sec;
220                 compat_event.time.tv_usec = event->time.tv_usec;
221                 compat_event.type = event->type;
222                 compat_event.code = event->code;
223                 compat_event.value = event->value;
224
225                 if (copy_to_user(buffer, &compat_event, sizeof(struct input_event_compat)))
226                         return -EFAULT;
227
228         } else {
229                 if (copy_to_user(buffer, event, sizeof(struct input_event)))
230                         return -EFAULT;
231         }
232
233         return 0;
234 }
235
236 #else
237
238 static inline size_t evdev_event_size(void)
239 {
240         return sizeof(struct input_event);
241 }
242
243 static int evdev_event_from_user(const char __user *buffer, struct input_event *event)
244 {
245         if (copy_from_user(event, buffer, sizeof(struct input_event)))
246                 return -EFAULT;
247
248         return 0;
249 }
250
251 static int evdev_event_to_user(char __user *buffer, const struct input_event *event)
252 {
253         if (copy_to_user(buffer, event, sizeof(struct input_event)))
254                 return -EFAULT;
255
256         return 0;
257 }
258
259 #endif /* CONFIG_COMPAT */
260
261 static ssize_t evdev_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
262 {
263         struct evdev_client *client = file->private_data;
264         struct evdev *evdev = client->evdev;
265         struct input_event event;
266         int retval = 0;
267
268         if (!evdev->exist)
269                 return -ENODEV;
270
271         while (retval < count) {
272
273                 if (evdev_event_from_user(buffer + retval, &event))
274                         return -EFAULT;
275                 input_inject_event(&evdev->handle, event.type, event.code, event.value);
276                 retval += evdev_event_size();
277         }
278
279         return retval;
280 }
281
282 static ssize_t evdev_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
283 {
284         struct evdev_client *client = file->private_data;
285         struct evdev *evdev = client->evdev;
286         int retval;
287
288         if (count < evdev_event_size())
289                 return -EINVAL;
290
291         if (client->head == client->tail && evdev->exist && (file->f_flags & O_NONBLOCK))
292                 return -EAGAIN;
293
294         retval = wait_event_interruptible(evdev->wait,
295                 client->head != client->tail || !evdev->exist);
296         if (retval)
297                 return retval;
298
299         if (!evdev->exist)
300                 return -ENODEV;
301
302         while (client->head != client->tail && retval + evdev_event_size() <= count) {
303
304                 struct input_event *event = (struct input_event *) client->buffer + client->tail;
305
306                 if (evdev_event_to_user(buffer + retval, event))
307                         return -EFAULT;
308
309                 client->tail = (client->tail + 1) & (EVDEV_BUFFER_SIZE - 1);
310                 retval += evdev_event_size();
311         }
312
313         return retval;
314 }
315
316 /* No kernel lock - fine */
317 static unsigned int evdev_poll(struct file *file, poll_table *wait)
318 {
319         struct evdev_client *client = file->private_data;
320         struct evdev *evdev = client->evdev;
321
322         poll_wait(file, &evdev->wait, wait);
323         return ((client->head == client->tail) ? 0 : (POLLIN | POLLRDNORM)) |
324                 (evdev->exist ? 0 : (POLLHUP | POLLERR));
325 }
326
327 #ifdef CONFIG_COMPAT
328
329 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
330 #define NBITS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1)
331
332 #ifdef __BIG_ENDIAN
333 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
334                         unsigned int maxlen, void __user *p, int compat)
335 {
336         int len, i;
337
338         if (compat) {
339                 len = NBITS_COMPAT(maxbit) * sizeof(compat_long_t);
340                 if (len < maxlen)
341                         len = maxlen;
342
343                 for (i = 0; i < len / sizeof(compat_long_t); i++)
344                         if (copy_to_user((compat_long_t __user *) p + i,
345                                          (compat_long_t *) bits +
346                                                 i + 1 - ((i % 2) << 1),
347                                          sizeof(compat_long_t)))
348                                 return -EFAULT;
349         } else {
350                 len = NBITS(maxbit) * sizeof(long);
351                 if (len > maxlen)
352                         len = maxlen;
353
354                 if (copy_to_user(p, bits, len))
355                         return -EFAULT;
356         }
357
358         return len;
359 }
360 #else
361 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
362                         unsigned int maxlen, void __user *p, int compat)
363 {
364         int len = compat ?
365                         NBITS_COMPAT(maxbit) * sizeof(compat_long_t) :
366                         NBITS(maxbit) * sizeof(long);
367
368         if (len > maxlen)
369                 len = maxlen;
370
371         return copy_to_user(p, bits, len) ? -EFAULT : len;
372 }
373 #endif /* __BIG_ENDIAN */
374
375 #else
376
377 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
378                         unsigned int maxlen, void __user *p, int compat)
379 {
380         int len = NBITS(maxbit) * sizeof(long);
381
382         if (len > maxlen)
383                 len = maxlen;
384
385         return copy_to_user(p, bits, len) ? -EFAULT : len;
386 }
387
388 #endif /* CONFIG_COMPAT */
389
390 static int str_to_user(const char *str, unsigned int maxlen, void __user *p)
391 {
392         int len;
393
394         if (!str)
395                 return -ENOENT;
396
397         len = strlen(str) + 1;
398         if (len > maxlen)
399                 len = maxlen;
400
401         return copy_to_user(p, str, len) ? -EFAULT : len;
402 }
403
404 static long evdev_ioctl_handler(struct file *file, unsigned int cmd,
405                                 void __user *p, int compat_mode)
406 {
407         struct evdev_client *client = file->private_data;
408         struct evdev *evdev = client->evdev;
409         struct input_dev *dev = evdev->handle.dev;
410         struct input_absinfo abs;
411         struct ff_effect effect;
412         int __user *ip = (int __user *)p;
413         int i, t, u, v;
414         int error;
415
416         if (!evdev->exist)
417                 return -ENODEV;
418
419         switch (cmd) {
420
421                 case EVIOCGVERSION:
422                         return put_user(EV_VERSION, ip);
423
424                 case EVIOCGID:
425                         if (copy_to_user(p, &dev->id, sizeof(struct input_id)))
426                                 return -EFAULT;
427                         return 0;
428
429                 case EVIOCGREP:
430                         if (!test_bit(EV_REP, dev->evbit))
431                                 return -ENOSYS;
432                         if (put_user(dev->rep[REP_DELAY], ip))
433                                 return -EFAULT;
434                         if (put_user(dev->rep[REP_PERIOD], ip + 1))
435                                 return -EFAULT;
436                         return 0;
437
438                 case EVIOCSREP:
439                         if (!test_bit(EV_REP, dev->evbit))
440                                 return -ENOSYS;
441                         if (get_user(u, ip))
442                                 return -EFAULT;
443                         if (get_user(v, ip + 1))
444                                 return -EFAULT;
445
446                         input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u);
447                         input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v);
448
449                         return 0;
450
451                 case EVIOCGKEYCODE:
452                         if (get_user(t, ip))
453                                 return -EFAULT;
454
455                         error = dev->getkeycode(dev, t, &v);
456                         if (error)
457                                 return error;
458
459                         if (put_user(v, ip + 1))
460                                 return -EFAULT;
461
462                         return 0;
463
464                 case EVIOCSKEYCODE:
465                         if (get_user(t, ip) || get_user(v, ip + 1))
466                                 return -EFAULT;
467
468                         return dev->setkeycode(dev, t, v);
469
470                 case EVIOCSFF:
471                         if (copy_from_user(&effect, p, sizeof(effect)))
472                                 return -EFAULT;
473
474                         error = input_ff_upload(dev, &effect, file);
475
476                         if (put_user(effect.id, &(((struct ff_effect __user *)p)->id)))
477                                 return -EFAULT;
478
479                         return error;
480
481                 case EVIOCRMFF:
482                         return input_ff_erase(dev, (int)(unsigned long) p, file);
483
484                 case EVIOCGEFFECTS:
485                         i = test_bit(EV_FF, dev->evbit) ? dev->ff->max_effects : 0;
486                         if (put_user(i, ip))
487                                 return -EFAULT;
488                         return 0;
489
490                 case EVIOCGRAB:
491                         if (p) {
492                                 if (evdev->grab)
493                                         return -EBUSY;
494                                 if (input_grab_device(&evdev->handle))
495                                         return -EBUSY;
496                                 evdev->grab = client;
497                                 return 0;
498                         } else {
499                                 if (evdev->grab != client)
500                                         return -EINVAL;
501                                 input_release_device(&evdev->handle);
502                                 evdev->grab = NULL;
503                                 return 0;
504                         }
505
506                 default:
507
508                         if (_IOC_TYPE(cmd) != 'E')
509                                 return -EINVAL;
510
511                         if (_IOC_DIR(cmd) == _IOC_READ) {
512
513                                 if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0,0))) {
514
515                                         unsigned long *bits;
516                                         int len;
517
518                                         switch (_IOC_NR(cmd) & EV_MAX) {
519                                                 case      0: bits = dev->evbit;  len = EV_MAX;  break;
520                                                 case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
521                                                 case EV_REL: bits = dev->relbit; len = REL_MAX; break;
522                                                 case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
523                                                 case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break;
524                                                 case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
525                                                 case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
526                                                 case EV_FF:  bits = dev->ffbit;  len = FF_MAX;  break;
527                                                 case EV_SW:  bits = dev->swbit;  len = SW_MAX;  break;
528                                                 default: return -EINVAL;
529                                         }
530                                         return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode);
531                                 }
532
533                                 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0)))
534                                         return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd),
535                                                             p, compat_mode);
536
537                                 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0)))
538                                         return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd),
539                                                             p, compat_mode);
540
541                                 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0)))
542                                         return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd),
543                                                             p, compat_mode);
544
545                                 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0)))
546                                         return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd),
547                                                             p, compat_mode);
548
549                                 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0)))
550                                         return str_to_user(dev->name, _IOC_SIZE(cmd), p);
551
552                                 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0)))
553                                         return str_to_user(dev->phys, _IOC_SIZE(cmd), p);
554
555                                 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0)))
556                                         return str_to_user(dev->uniq, _IOC_SIZE(cmd), p);
557
558                                 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
559
560                                         t = _IOC_NR(cmd) & ABS_MAX;
561
562                                         abs.value = dev->abs[t];
563                                         abs.minimum = dev->absmin[t];
564                                         abs.maximum = dev->absmax[t];
565                                         abs.fuzz = dev->absfuzz[t];
566                                         abs.flat = dev->absflat[t];
567
568                                         if (copy_to_user(p, &abs, sizeof(struct input_absinfo)))
569                                                 return -EFAULT;
570
571                                         return 0;
572                                 }
573
574                         }
575
576                         if (_IOC_DIR(cmd) == _IOC_WRITE) {
577
578                                 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
579
580                                         t = _IOC_NR(cmd) & ABS_MAX;
581
582                                         if (copy_from_user(&abs, p, sizeof(struct input_absinfo)))
583                                                 return -EFAULT;
584
585                                         dev->abs[t] = abs.value;
586                                         dev->absmin[t] = abs.minimum;
587                                         dev->absmax[t] = abs.maximum;
588                                         dev->absfuzz[t] = abs.fuzz;
589                                         dev->absflat[t] = abs.flat;
590
591                                         return 0;
592                                 }
593                         }
594         }
595         return -EINVAL;
596 }
597
598 static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
599 {
600         return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0);
601 }
602
603 #ifdef CONFIG_COMPAT
604 static long evdev_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
605 {
606         return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1);
607 }
608 #endif
609
610 static const struct file_operations evdev_fops = {
611         .owner =        THIS_MODULE,
612         .read =         evdev_read,
613         .write =        evdev_write,
614         .poll =         evdev_poll,
615         .open =         evdev_open,
616         .release =      evdev_release,
617         .unlocked_ioctl = evdev_ioctl,
618 #ifdef CONFIG_COMPAT
619         .compat_ioctl = evdev_ioctl_compat,
620 #endif
621         .fasync =       evdev_fasync,
622         .flush =        evdev_flush
623 };
624
625 static int evdev_connect(struct input_handler *handler, struct input_dev *dev,
626                          const struct input_device_id *id)
627 {
628         struct evdev *evdev;
629         struct class_device *cdev;
630         dev_t devt;
631         int minor;
632         int error;
633
634         for (minor = 0; minor < EVDEV_MINORS && evdev_table[minor]; minor++);
635         if (minor == EVDEV_MINORS) {
636                 printk(KERN_ERR "evdev: no more free evdev devices\n");
637                 return -ENFILE;
638         }
639
640         evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL);
641         if (!evdev)
642                 return -ENOMEM;
643
644         INIT_LIST_HEAD(&evdev->client_list);
645         init_waitqueue_head(&evdev->wait);
646
647         evdev->exist = 1;
648         evdev->minor = minor;
649         evdev->handle.dev = dev;
650         evdev->handle.name = evdev->name;
651         evdev->handle.handler = handler;
652         evdev->handle.private = evdev;
653         sprintf(evdev->name, "event%d", minor);
654
655         evdev_table[minor] = evdev;
656
657         devt = MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor),
658
659         cdev = class_device_create(&input_class, &dev->cdev, devt,
660                                    dev->cdev.dev, evdev->name);
661         if (IS_ERR(cdev)) {
662                 error = PTR_ERR(cdev);
663                 goto err_free_evdev;
664         }
665
666         /* temporary symlink to keep userspace happy */
667         error = sysfs_create_link(&input_class.subsys.kobj,
668                                   &cdev->kobj, evdev->name);
669         if (error)
670                 goto err_cdev_destroy;
671
672         error = input_register_handle(&evdev->handle);
673         if (error)
674                 goto err_remove_link;
675
676         return 0;
677
678  err_remove_link:
679         sysfs_remove_link(&input_class.subsys.kobj, evdev->name);
680  err_cdev_destroy:
681         class_device_destroy(&input_class, devt);
682  err_free_evdev:
683         kfree(evdev);
684         evdev_table[minor] = NULL;
685         return error;
686 }
687
688 static void evdev_disconnect(struct input_handle *handle)
689 {
690         struct evdev *evdev = handle->private;
691         struct evdev_client *client;
692
693         input_unregister_handle(handle);
694
695         sysfs_remove_link(&input_class.subsys.kobj, evdev->name);
696         class_device_destroy(&input_class,
697                         MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + evdev->minor));
698         evdev->exist = 0;
699
700         if (evdev->open) {
701                 input_flush_device(handle, NULL);
702                 input_close_device(handle);
703                 list_for_each_entry(client, &evdev->client_list, node)
704                         kill_fasync(&client->fasync, SIGIO, POLL_HUP);
705                 wake_up_interruptible(&evdev->wait);
706         } else
707                 evdev_free(evdev);
708 }
709
710 static const 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         return input_register_handler(&evdev_handler);
730 }
731
732 static void __exit evdev_exit(void)
733 {
734         input_unregister_handler(&evdev_handler);
735 }
736
737 module_init(evdev_init);
738 module_exit(evdev_exit);
739
740 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
741 MODULE_DESCRIPTION("Input driver event char devices");
742 MODULE_LICENSE("GPL");