projects/linux·blob v2.6.30 · refs

891 lines · 19.9 KiB

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/device.h>
22#include "input-compat.h"
23
24struct evdev {
25 int exist;
26 int open;
27 int minor;
28 char name[16];
29 struct input_handle handle;
30 wait_queue_head_t wait;
31 struct evdev_client *grab;
32 struct list_head client_list;
33 spinlock_t client_lock; /* protects client_list */
34 struct mutex mutex;
35 struct device dev;
36};
37
38struct evdev_client {
39 struct input_event buffer[EVDEV_BUFFER_SIZE];
40 int head;
41 int tail;
42 spinlock_t buffer_lock; /* protects access to buffer, head and tail */
43 struct fasync_struct *fasync;
44 struct evdev *evdev;
45 struct list_head node;
46};
47
48static struct evdev *evdev_table[EVDEV_MINORS];
49static DEFINE_MUTEX(evdev_table_mutex);
50
51static void evdev_pass_event(struct evdev_client *client,
52 struct input_event *event)
53{
54 /*
55 * Interrupts are disabled, just acquire the lock
56 */
57 spin_lock(&client->buffer_lock);
58 client->buffer[client->head++] = *event;
59 client->head &= EVDEV_BUFFER_SIZE - 1;
60 spin_unlock(&client->buffer_lock);
61
62 kill_fasync(&client->fasync, SIGIO, POLL_IN);
63}
64
65/*
66 * Pass incoming event to all connected clients.
67 */
68static void evdev_event(struct input_handle *handle,
69 unsigned int type, unsigned int code, int value)
70{
71 struct evdev *evdev = handle->private;
72 struct evdev_client *client;
73 struct input_event event;
74
75 do_gettimeofday(&event.time);
76 event.type = type;
77 event.code = code;
78 event.value = value;
79
80 rcu_read_lock();
81
82 client = rcu_dereference(evdev->grab);
83 if (client)
84 evdev_pass_event(client, &event);
85 else
86 list_for_each_entry_rcu(client, &evdev->client_list, node)
87 evdev_pass_event(client, &event);
88
89 rcu_read_unlock();
90
91 wake_up_interruptible(&evdev->wait);
92}
93
94static int evdev_fasync(int fd, struct file *file, int on)
95{
96 struct evdev_client *client = file->private_data;
97
98 return fasync_helper(fd, file, on, &client->fasync);
99}
100
101static int evdev_flush(struct file *file, fl_owner_t id)
102{
103 struct evdev_client *client = file->private_data;
104 struct evdev *evdev = client->evdev;
105 int retval;
106
107 retval = mutex_lock_interruptible(&evdev->mutex);
108 if (retval)
109 return retval;
110
111 if (!evdev->exist)
112 retval = -ENODEV;
113 else
114 retval = input_flush_device(&evdev->handle, file);
115
116 mutex_unlock(&evdev->mutex);
117 return retval;
118}
119
120static void evdev_free(struct device *dev)
121{
122 struct evdev *evdev = container_of(dev, struct evdev, dev);
123
124 input_put_device(evdev->handle.dev);
125 kfree(evdev);
126}
127
128/*
129 * Grabs an event device (along with underlying input device).
130 * This function is called with evdev->mutex taken.
131 */
132static int evdev_grab(struct evdev *evdev, struct evdev_client *client)
133{
134 int error;
135
136 if (evdev->grab)
137 return -EBUSY;
138
139 error = input_grab_device(&evdev->handle);
140 if (error)
141 return error;
142
143 rcu_assign_pointer(evdev->grab, client);
144 synchronize_rcu();
145
146 return 0;
147}
148
149static int evdev_ungrab(struct evdev *evdev, struct evdev_client *client)
150{
151 if (evdev->grab != client)
152 return -EINVAL;
153
154 rcu_assign_pointer(evdev->grab, NULL);
155 synchronize_rcu();
156 input_release_device(&evdev->handle);
157
158 return 0;
159}
160
161static void evdev_attach_client(struct evdev *evdev,
162 struct evdev_client *client)
163{
164 spin_lock(&evdev->client_lock);
165 list_add_tail_rcu(&client->node, &evdev->client_list);
166 spin_unlock(&evdev->client_lock);
167 synchronize_rcu();
168}
169
170static void evdev_detach_client(struct evdev *evdev,
171 struct evdev_client *client)
172{
173 spin_lock(&evdev->client_lock);
174 list_del_rcu(&client->node);
175 spin_unlock(&evdev->client_lock);
176 synchronize_rcu();
177}
178
179static int evdev_open_device(struct evdev *evdev)
180{
181 int retval;
182
183 retval = mutex_lock_interruptible(&evdev->mutex);
184 if (retval)
185 return retval;
186
187 if (!evdev->exist)
188 retval = -ENODEV;
189 else if (!evdev->open++) {
190 retval = input_open_device(&evdev->handle);
191 if (retval)
192 evdev->open--;
193 }
194
195 mutex_unlock(&evdev->mutex);
196 return retval;
197}
198
199static void evdev_close_device(struct evdev *evdev)
200{
201 mutex_lock(&evdev->mutex);
202
203 if (evdev->exist && !--evdev->open)
204 input_close_device(&evdev->handle);
205
206 mutex_unlock(&evdev->mutex);
207}
208
209/*
210 * Wake up users waiting for IO so they can disconnect from
211 * dead device.
212 */
213static void evdev_hangup(struct evdev *evdev)
214{
215 struct evdev_client *client;
216
217 spin_lock(&evdev->client_lock);
218 list_for_each_entry(client, &evdev->client_list, node)
219 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
220 spin_unlock(&evdev->client_lock);
221
222 wake_up_interruptible(&evdev->wait);
223}
224
225static int evdev_release(struct inode *inode, struct file *file)
226{
227 struct evdev_client *client = file->private_data;
228 struct evdev *evdev = client->evdev;
229
230 mutex_lock(&evdev->mutex);
231 if (evdev->grab == client)
232 evdev_ungrab(evdev, client);
233 mutex_unlock(&evdev->mutex);
234
235 evdev_detach_client(evdev, client);
236 kfree(client);
237
238 evdev_close_device(evdev);
239 put_device(&evdev->dev);
240
241 return 0;
242}
243
244static int evdev_open(struct inode *inode, struct file *file)
245{
246 struct evdev *evdev;
247 struct evdev_client *client;
248 int i = iminor(inode) - EVDEV_MINOR_BASE;
249 int error;
250
251 if (i >= EVDEV_MINORS)
252 return -ENODEV;
253
254 error = mutex_lock_interruptible(&evdev_table_mutex);
255 if (error)
256 return error;
257 evdev = evdev_table[i];
258 if (evdev)
259 get_device(&evdev->dev);
260 mutex_unlock(&evdev_table_mutex);
261
262 if (!evdev)
263 return -ENODEV;
264
265 client = kzalloc(sizeof(struct evdev_client), GFP_KERNEL);
266 if (!client) {
267 error = -ENOMEM;
268 goto err_put_evdev;
269 }
270
271 spin_lock_init(&client->buffer_lock);
272 client->evdev = evdev;
273 evdev_attach_client(evdev, client);
274
275 error = evdev_open_device(evdev);
276 if (error)
277 goto err_free_client;
278
279 file->private_data = client;
280 return 0;
281
282 err_free_client:
283 evdev_detach_client(evdev, client);
284 kfree(client);
285 err_put_evdev:
286 put_device(&evdev->dev);
287 return error;
288}
289
290static ssize_t evdev_write(struct file *file, const char __user *buffer,
291 size_t count, loff_t *ppos)
292{
293 struct evdev_client *client = file->private_data;
294 struct evdev *evdev = client->evdev;
295 struct input_event event;
296 int retval;
297
298 retval = mutex_lock_interruptible(&evdev->mutex);
299 if (retval)
300 return retval;
301
302 if (!evdev->exist) {
303 retval = -ENODEV;
304 goto out;
305 }
306
307 while (retval < count) {
308
309 if (input_event_from_user(buffer + retval, &event)) {
310 retval = -EFAULT;
311 goto out;
312 }
313
314 input_inject_event(&evdev->handle,
315 event.type, event.code, event.value);
316 retval += input_event_size();
317 }
318
319 out:
320 mutex_unlock(&evdev->mutex);
321 return retval;
322}
323
324static int evdev_fetch_next_event(struct evdev_client *client,
325 struct input_event *event)
326{
327 int have_event;
328
329 spin_lock_irq(&client->buffer_lock);
330
331 have_event = client->head != client->tail;
332 if (have_event) {
333 *event = client->buffer[client->tail++];
334 client->tail &= EVDEV_BUFFER_SIZE - 1;
335 }
336
337 spin_unlock_irq(&client->buffer_lock);
338
339 return have_event;
340}
341
342static ssize_t evdev_read(struct file *file, char __user *buffer,
343 size_t count, loff_t *ppos)
344{
345 struct evdev_client *client = file->private_data;
346 struct evdev *evdev = client->evdev;
347 struct input_event event;
348 int retval;
349
350 if (count < input_event_size())
351 return -EINVAL;
352
353 if (client->head == client->tail && evdev->exist &&
354 (file->f_flags & O_NONBLOCK))
355 return -EAGAIN;
356
357 retval = wait_event_interruptible(evdev->wait,
358 client->head != client->tail || !evdev->exist);
359 if (retval)
360 return retval;
361
362 if (!evdev->exist)
363 return -ENODEV;
364
365 while (retval + input_event_size() <= count &&
366 evdev_fetch_next_event(client, &event)) {
367
368 if (input_event_to_user(buffer + retval, &event))
369 return -EFAULT;
370
371 retval += input_event_size();
372 }
373
374 return retval;
375}
376
377/* No kernel lock - fine */
378static unsigned int evdev_poll(struct file *file, poll_table *wait)
379{
380 struct evdev_client *client = file->private_data;
381 struct evdev *evdev = client->evdev;
382
383 poll_wait(file, &evdev->wait, wait);
384 return ((client->head == client->tail) ? 0 : (POLLIN | POLLRDNORM)) |
385 (evdev->exist ? 0 : (POLLHUP | POLLERR));
386}
387
388#ifdef CONFIG_COMPAT
389
390#define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
391#define BITS_TO_LONGS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1)
392
393#ifdef __BIG_ENDIAN
394static int bits_to_user(unsigned long *bits, unsigned int maxbit,
395 unsigned int maxlen, void __user *p, int compat)
396{
397 int len, i;
398
399 if (compat) {
400 len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t);
401 if (len > maxlen)
402 len = maxlen;
403
404 for (i = 0; i < len / sizeof(compat_long_t); i++)
405 if (copy_to_user((compat_long_t __user *) p + i,
406 (compat_long_t *) bits +
407 i + 1 - ((i % 2) << 1),
408 sizeof(compat_long_t)))
409 return -EFAULT;
410 } else {
411 len = BITS_TO_LONGS(maxbit) * sizeof(long);
412 if (len > maxlen)
413 len = maxlen;
414
415 if (copy_to_user(p, bits, len))
416 return -EFAULT;
417 }
418
419 return len;
420}
421#else
422static int bits_to_user(unsigned long *bits, unsigned int maxbit,
423 unsigned int maxlen, void __user *p, int compat)
424{
425 int len = compat ?
426 BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t) :
427 BITS_TO_LONGS(maxbit) * sizeof(long);
428
429 if (len > maxlen)
430 len = maxlen;
431
432 return copy_to_user(p, bits, len) ? -EFAULT : len;
433}
434#endif /* __BIG_ENDIAN */
435
436#else
437
438static int bits_to_user(unsigned long *bits, unsigned int maxbit,
439 unsigned int maxlen, void __user *p, int compat)
440{
441 int len = BITS_TO_LONGS(maxbit) * sizeof(long);
442
443 if (len > maxlen)
444 len = maxlen;
445
446 return copy_to_user(p, bits, len) ? -EFAULT : len;
447}
448
449#endif /* CONFIG_COMPAT */
450
451static int str_to_user(const char *str, unsigned int maxlen, void __user *p)
452{
453 int len;
454
455 if (!str)
456 return -ENOENT;
457
458 len = strlen(str) + 1;
459 if (len > maxlen)
460 len = maxlen;
461
462 return copy_to_user(p, str, len) ? -EFAULT : len;
463}
464
465#define OLD_KEY_MAX 0x1ff
466static int handle_eviocgbit(struct input_dev *dev, unsigned int cmd, void __user *p, int compat_mode)
467{
468 static unsigned long keymax_warn_time;
469 unsigned long *bits;
470 int len;
471
472 switch (_IOC_NR(cmd) & EV_MAX) {
473
474 case 0: bits = dev->evbit; len = EV_MAX; break;
475 case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
476 case EV_REL: bits = dev->relbit; len = REL_MAX; break;
477 case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
478 case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break;
479 case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
480 case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
481 case EV_FF: bits = dev->ffbit; len = FF_MAX; break;
482 case EV_SW: bits = dev->swbit; len = SW_MAX; break;
483 default: return -EINVAL;
484 }
485
486 /*
487 * Work around bugs in userspace programs that like to do
488 * EVIOCGBIT(EV_KEY, KEY_MAX) and not realize that 'len'
489 * should be in bytes, not in bits.
490 */
491 if ((_IOC_NR(cmd) & EV_MAX) == EV_KEY && _IOC_SIZE(cmd) == OLD_KEY_MAX) {
492 len = OLD_KEY_MAX;
493 if (printk_timed_ratelimit(&keymax_warn_time, 10 * 1000))
494 printk(KERN_WARNING
495 "evdev.c(EVIOCGBIT): Suspicious buffer size %u, "
496 "limiting output to %zu bytes. See "
497 "http://userweb.kernel.org/~dtor/eviocgbit-bug.html\n",
498 OLD_KEY_MAX,
499 BITS_TO_LONGS(OLD_KEY_MAX) * sizeof(long));
500 }
501
502 return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode);
503}
504#undef OLD_KEY_MAX
505
506static long evdev_do_ioctl(struct file *file, unsigned int cmd,
507 void __user *p, int compat_mode)
508{
509 struct evdev_client *client = file->private_data;
510 struct evdev *evdev = client->evdev;
511 struct input_dev *dev = evdev->handle.dev;
512 struct input_absinfo abs;
513 struct ff_effect effect;
514 int __user *ip = (int __user *)p;
515 int i, t, u, v;
516 int error;
517
518 switch (cmd) {
519
520 case EVIOCGVERSION:
521 return put_user(EV_VERSION, ip);
522
523 case EVIOCGID:
524 if (copy_to_user(p, &dev->id, sizeof(struct input_id)))
525 return -EFAULT;
526 return 0;
527
528 case EVIOCGREP:
529 if (!test_bit(EV_REP, dev->evbit))
530 return -ENOSYS;
531 if (put_user(dev->rep[REP_DELAY], ip))
532 return -EFAULT;
533 if (put_user(dev->rep[REP_PERIOD], ip + 1))
534 return -EFAULT;
535 return 0;
536
537 case EVIOCSREP:
538 if (!test_bit(EV_REP, dev->evbit))
539 return -ENOSYS;
540 if (get_user(u, ip))
541 return -EFAULT;
542 if (get_user(v, ip + 1))
543 return -EFAULT;
544
545 input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u);
546 input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v);
547
548 return 0;
549
550 case EVIOCGKEYCODE:
551 if (get_user(t, ip))
552 return -EFAULT;
553
554 error = input_get_keycode(dev, t, &v);
555 if (error)
556 return error;
557
558 if (put_user(v, ip + 1))
559 return -EFAULT;
560
561 return 0;
562
563 case EVIOCSKEYCODE:
564 if (get_user(t, ip) || get_user(v, ip + 1))
565 return -EFAULT;
566
567 return input_set_keycode(dev, t, v);
568
569 case EVIOCRMFF:
570 return input_ff_erase(dev, (int)(unsigned long) p, file);
571
572 case EVIOCGEFFECTS:
573 i = test_bit(EV_FF, dev->evbit) ?
574 dev->ff->max_effects : 0;
575 if (put_user(i, ip))
576 return -EFAULT;
577 return 0;
578
579 case EVIOCGRAB:
580 if (p)
581 return evdev_grab(evdev, client);
582 else
583 return evdev_ungrab(evdev, client);
584
585 default:
586
587 if (_IOC_TYPE(cmd) != 'E')
588 return -EINVAL;
589
590 if (_IOC_DIR(cmd) == _IOC_READ) {
591
592 if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0, 0)))
593 return handle_eviocgbit(dev, cmd, p, compat_mode);
594
595 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0)))
596 return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd),
597 p, compat_mode);
598
599 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0)))
600 return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd),
601 p, compat_mode);
602
603 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0)))
604 return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd),
605 p, compat_mode);
606
607 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0)))
608 return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd),
609 p, compat_mode);
610
611 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0)))
612 return str_to_user(dev->name, _IOC_SIZE(cmd), p);
613
614 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0)))
615 return str_to_user(dev->phys, _IOC_SIZE(cmd), p);
616
617 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0)))
618 return str_to_user(dev->uniq, _IOC_SIZE(cmd), p);
619
620 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
621
622 t = _IOC_NR(cmd) & ABS_MAX;
623
624 abs.value = dev->abs[t];
625 abs.minimum = dev->absmin[t];
626 abs.maximum = dev->absmax[t];
627 abs.fuzz = dev->absfuzz[t];
628 abs.flat = dev->absflat[t];
629
630 if (copy_to_user(p, &abs, sizeof(struct input_absinfo)))
631 return -EFAULT;
632
633 return 0;
634 }
635
636 }
637
638 if (_IOC_DIR(cmd) == _IOC_WRITE) {
639
640 if (_IOC_NR(cmd) == _IOC_NR(EVIOCSFF)) {
641
642 if (input_ff_effect_from_user(p, _IOC_SIZE(cmd), &effect))
643 return -EFAULT;
644
645 error = input_ff_upload(dev, &effect, file);
646
647 if (put_user(effect.id, &(((struct ff_effect __user *)p)->id)))
648 return -EFAULT;
649
650 return error;
651 }
652
653 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
654
655 t = _IOC_NR(cmd) & ABS_MAX;
656
657 if (copy_from_user(&abs, p,
658 sizeof(struct input_absinfo)))
659 return -EFAULT;
660
661 /*
662 * Take event lock to ensure that we are not
663 * changing device parameters in the middle
664 * of event.
665 */
666 spin_lock_irq(&dev->event_lock);
667
668 dev->abs[t] = abs.value;
669 dev->absmin[t] = abs.minimum;
670 dev->absmax[t] = abs.maximum;
671 dev->absfuzz[t] = abs.fuzz;
672 dev->absflat[t] = abs.flat;
673
674 spin_unlock_irq(&dev->event_lock);
675
676 return 0;
677 }
678 }
679 }
680 return -EINVAL;
681}
682
683static long evdev_ioctl_handler(struct file *file, unsigned int cmd,
684 void __user *p, int compat_mode)
685{
686 struct evdev_client *client = file->private_data;
687 struct evdev *evdev = client->evdev;
688 int retval;
689
690 retval = mutex_lock_interruptible(&evdev->mutex);
691 if (retval)
692 return retval;
693
694 if (!evdev->exist) {
695 retval = -ENODEV;
696 goto out;
697 }
698
699 retval = evdev_do_ioctl(file, cmd, p, compat_mode);
700
701 out:
702 mutex_unlock(&evdev->mutex);
703 return retval;
704}
705
706static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
707{
708 return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0);
709}
710
711#ifdef CONFIG_COMPAT
712static long evdev_ioctl_compat(struct file *file,
713 unsigned int cmd, unsigned long arg)
714{
715 return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1);
716}
717#endif
718
719static const struct file_operations evdev_fops = {
720 .owner = THIS_MODULE,
721 .read = evdev_read,
722 .write = evdev_write,
723 .poll = evdev_poll,
724 .open = evdev_open,
725 .release = evdev_release,
726 .unlocked_ioctl = evdev_ioctl,
727#ifdef CONFIG_COMPAT
728 .compat_ioctl = evdev_ioctl_compat,
729#endif
730 .fasync = evdev_fasync,
731 .flush = evdev_flush
732};
733
734static int evdev_install_chrdev(struct evdev *evdev)
735{
736 /*
737 * No need to do any locking here as calls to connect and
738 * disconnect are serialized by the input core
739 */
740 evdev_table[evdev->minor] = evdev;
741 return 0;
742}
743
744static void evdev_remove_chrdev(struct evdev *evdev)
745{
746 /*
747 * Lock evdev table to prevent race with evdev_open()
748 */
749 mutex_lock(&evdev_table_mutex);
750 evdev_table[evdev->minor] = NULL;
751 mutex_unlock(&evdev_table_mutex);
752}
753
754/*
755 * Mark device non-existent. This disables writes, ioctls and
756 * prevents new users from opening the device. Already posted
757 * blocking reads will stay, however new ones will fail.
758 */
759static void evdev_mark_dead(struct evdev *evdev)
760{
761 mutex_lock(&evdev->mutex);
762 evdev->exist = 0;
763 mutex_unlock(&evdev->mutex);
764}
765
766static void evdev_cleanup(struct evdev *evdev)
767{
768 struct input_handle *handle = &evdev->handle;
769
770 evdev_mark_dead(evdev);
771 evdev_hangup(evdev);
772 evdev_remove_chrdev(evdev);
773
774 /* evdev is marked dead so no one else accesses evdev->open */
775 if (evdev->open) {
776 input_flush_device(handle, NULL);
777 input_close_device(handle);
778 }
779}
780
781/*
782 * Create new evdev device. Note that input core serializes calls
783 * to connect and disconnect so we don't need to lock evdev_table here.
784 */
785static int evdev_connect(struct input_handler *handler, struct input_dev *dev,
786 const struct input_device_id *id)
787{
788 struct evdev *evdev;
789 int minor;
790 int error;
791
792 for (minor = 0; minor < EVDEV_MINORS; minor++)
793 if (!evdev_table[minor])
794 break;
795
796 if (minor == EVDEV_MINORS) {
797 printk(KERN_ERR "evdev: no more free evdev devices\n");
798 return -ENFILE;
799 }
800
801 evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL);
802 if (!evdev)
803 return -ENOMEM;
804
805 INIT_LIST_HEAD(&evdev->client_list);
806 spin_lock_init(&evdev->client_lock);
807 mutex_init(&evdev->mutex);
808 init_waitqueue_head(&evdev->wait);
809
810 snprintf(evdev->name, sizeof(evdev->name), "event%d", minor);
811 evdev->exist = 1;
812 evdev->minor = minor;
813
814 evdev->handle.dev = input_get_device(dev);
815 evdev->handle.name = evdev->name;
816 evdev->handle.handler = handler;
817 evdev->handle.private = evdev;
818
819 dev_set_name(&evdev->dev, evdev->name);
820 evdev->dev.devt = MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor);
821 evdev->dev.class = &input_class;
822 evdev->dev.parent = &dev->dev;
823 evdev->dev.release = evdev_free;
824 device_initialize(&evdev->dev);
825
826 error = input_register_handle(&evdev->handle);
827 if (error)
828 goto err_free_evdev;
829
830 error = evdev_install_chrdev(evdev);
831 if (error)
832 goto err_unregister_handle;
833
834 error = device_add(&evdev->dev);
835 if (error)
836 goto err_cleanup_evdev;
837
838 return 0;
839
840 err_cleanup_evdev:
841 evdev_cleanup(evdev);
842 err_unregister_handle:
843 input_unregister_handle(&evdev->handle);
844 err_free_evdev:
845 put_device(&evdev->dev);
846 return error;
847}
848
849static void evdev_disconnect(struct input_handle *handle)
850{
851 struct evdev *evdev = handle->private;
852
853 device_del(&evdev->dev);
854 evdev_cleanup(evdev);
855 input_unregister_handle(handle);
856 put_device(&evdev->dev);
857}
858
859static const struct input_device_id evdev_ids[] = {
860 { .driver_info = 1 }, /* Matches all devices */
861 { }, /* Terminating zero entry */
862};
863
864MODULE_DEVICE_TABLE(input, evdev_ids);
865
866static struct input_handler evdev_handler = {
867 .event = evdev_event,
868 .connect = evdev_connect,
869 .disconnect = evdev_disconnect,
870 .fops = &evdev_fops,
871 .minor = EVDEV_MINOR_BASE,
872 .name = "evdev",
873 .id_table = evdev_ids,
874};
875
876static int __init evdev_init(void)
877{
878 return input_register_handler(&evdev_handler);
879}
880
881static void __exit evdev_exit(void)
882{
883 input_unregister_handler(&evdev_handler);
884}
885
886module_init(evdev_init);
887module_exit(evdev_exit);
888
889MODULE_AUTHOR("Vojtech Pavlik <[email protected]>");
890MODULE_DESCRIPTION("Input driver event char devices");
891MODULE_LICENSE("GPL");