ed8baa0aec3cce31023a2e97557db22ab5a7f7c6
[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/device.h>
22 #include "input-compat.h"
23
24 struct 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
38 struct 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
48 static struct evdev *evdev_table[EVDEV_MINORS];
49 static DEFINE_MUTEX(evdev_table_mutex);
50
51 static 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  */
68 static 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
94 static int evdev_fasync(int fd, struct file *file, int on)
95 {
96         struct evdev_client *client = file->private_data;
97         int retval;
98
99         retval = fasync_helper(fd, file, on, &client->fasync);
100
101         return retval < 0 ? retval : 0;
102 }
103
104 static int evdev_flush(struct file *file, fl_owner_t id)
105 {
106         struct evdev_client *client = file->private_data;
107         struct evdev *evdev = client->evdev;
108         int retval;
109
110         retval = mutex_lock_interruptible(&evdev->mutex);
111         if (retval)
112                 return retval;
113
114         if (!evdev->exist)
115                 retval = -ENODEV;
116         else
117                 retval = input_flush_device(&evdev->handle, file);
118
119         mutex_unlock(&evdev->mutex);
120         return retval;
121 }
122
123 static void evdev_free(struct device *dev)
124 {
125         struct evdev *evdev = container_of(dev, struct evdev, dev);
126
127         input_put_device(evdev->handle.dev);
128         kfree(evdev);
129 }
130
131 /*
132  * Grabs an event device (along with underlying input device).
133  * This function is called with evdev->mutex taken.
134  */
135 static int evdev_grab(struct evdev *evdev, struct evdev_client *client)
136 {
137         int error;
138
139         if (evdev->grab)
140                 return -EBUSY;
141
142         error = input_grab_device(&evdev->handle);
143         if (error)
144                 return error;
145
146         rcu_assign_pointer(evdev->grab, client);
147         synchronize_rcu();
148
149         return 0;
150 }
151
152 static int evdev_ungrab(struct evdev *evdev, struct evdev_client *client)
153 {
154         if (evdev->grab != client)
155                 return  -EINVAL;
156
157         rcu_assign_pointer(evdev->grab, NULL);
158         synchronize_rcu();
159         input_release_device(&evdev->handle);
160
161         return 0;
162 }
163
164 static void evdev_attach_client(struct evdev *evdev,
165                                 struct evdev_client *client)
166 {
167         spin_lock(&evdev->client_lock);
168         list_add_tail_rcu(&client->node, &evdev->client_list);
169         spin_unlock(&evdev->client_lock);
170         synchronize_rcu();
171 }
172
173 static void evdev_detach_client(struct evdev *evdev,
174                                 struct evdev_client *client)
175 {
176         spin_lock(&evdev->client_lock);
177         list_del_rcu(&client->node);
178         spin_unlock(&evdev->client_lock);
179         synchronize_rcu();
180 }
181
182 static int evdev_open_device(struct evdev *evdev)
183 {
184         int retval;
185
186         retval = mutex_lock_interruptible(&evdev->mutex);
187         if (retval)
188                 return retval;
189
190         if (!evdev->exist)
191                 retval = -ENODEV;
192         else if (!evdev->open++) {
193                 retval = input_open_device(&evdev->handle);
194                 if (retval)
195                         evdev->open--;
196         }
197
198         mutex_unlock(&evdev->mutex);
199         return retval;
200 }
201
202 static void evdev_close_device(struct evdev *evdev)
203 {
204         mutex_lock(&evdev->mutex);
205
206         if (evdev->exist && !--evdev->open)
207                 input_close_device(&evdev->handle);
208
209         mutex_unlock(&evdev->mutex);
210 }
211
212 /*
213  * Wake up users waiting for IO so they can disconnect from
214  * dead device.
215  */
216 static void evdev_hangup(struct evdev *evdev)
217 {
218         struct evdev_client *client;
219
220         spin_lock(&evdev->client_lock);
221         list_for_each_entry(client, &evdev->client_list, node)
222                 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
223         spin_unlock(&evdev->client_lock);
224
225         wake_up_interruptible(&evdev->wait);
226 }
227
228 static int evdev_release(struct inode *inode, struct file *file)
229 {
230         struct evdev_client *client = file->private_data;
231         struct evdev *evdev = client->evdev;
232
233         mutex_lock(&evdev->mutex);
234         if (evdev->grab == client)
235                 evdev_ungrab(evdev, client);
236         mutex_unlock(&evdev->mutex);
237
238         evdev_detach_client(evdev, client);
239         kfree(client);
240
241         evdev_close_device(evdev);
242         put_device(&evdev->dev);
243
244         return 0;
245 }
246
247 static int evdev_open(struct inode *inode, struct file *file)
248 {
249         struct evdev *evdev;
250         struct evdev_client *client;
251         int i = iminor(inode) - EVDEV_MINOR_BASE;
252         int error;
253
254         if (i >= EVDEV_MINORS)
255                 return -ENODEV;
256
257         error = mutex_lock_interruptible(&evdev_table_mutex);
258         if (error)
259                 return error;
260         evdev = evdev_table[i];
261         if (evdev)
262                 get_device(&evdev->dev);
263         mutex_unlock(&evdev_table_mutex);
264
265         if (!evdev)
266                 return -ENODEV;
267
268         client = kzalloc(sizeof(struct evdev_client), GFP_KERNEL);
269         if (!client) {
270                 error = -ENOMEM;
271                 goto err_put_evdev;
272         }
273
274         spin_lock_init(&client->buffer_lock);
275         client->evdev = evdev;
276         evdev_attach_client(evdev, client);
277
278         error = evdev_open_device(evdev);
279         if (error)
280                 goto err_free_client;
281
282         file->private_data = client;
283         return 0;
284
285  err_free_client:
286         evdev_detach_client(evdev, client);
287         kfree(client);
288  err_put_evdev:
289         put_device(&evdev->dev);
290         return error;
291 }
292
293 static ssize_t evdev_write(struct file *file, const char __user *buffer,
294                            size_t count, loff_t *ppos)
295 {
296         struct evdev_client *client = file->private_data;
297         struct evdev *evdev = client->evdev;
298         struct input_event event;
299         int retval;
300
301         retval = mutex_lock_interruptible(&evdev->mutex);
302         if (retval)
303                 return retval;
304
305         if (!evdev->exist) {
306                 retval = -ENODEV;
307                 goto out;
308         }
309
310         while (retval < count) {
311
312                 if (input_event_from_user(buffer + retval, &event)) {
313                         retval = -EFAULT;
314                         goto out;
315                 }
316
317                 input_inject_event(&evdev->handle,
318                                    event.type, event.code, event.value);
319                 retval += input_event_size();
320         }
321
322  out:
323         mutex_unlock(&evdev->mutex);
324         return retval;
325 }
326
327 static int evdev_fetch_next_event(struct evdev_client *client,
328                                   struct input_event *event)
329 {
330         int have_event;
331
332         spin_lock_irq(&client->buffer_lock);
333
334         have_event = client->head != client->tail;
335         if (have_event) {
336                 *event = client->buffer[client->tail++];
337                 client->tail &= EVDEV_BUFFER_SIZE - 1;
338         }
339
340         spin_unlock_irq(&client->buffer_lock);
341
342         return have_event;
343 }
344
345 static ssize_t evdev_read(struct file *file, char __user *buffer,
346                           size_t count, loff_t *ppos)
347 {
348         struct evdev_client *client = file->private_data;
349         struct evdev *evdev = client->evdev;
350         struct input_event event;
351         int retval;
352
353         if (count < input_event_size())
354                 return -EINVAL;
355
356         if (client->head == client->tail && evdev->exist &&
357             (file->f_flags & O_NONBLOCK))
358                 return -EAGAIN;
359
360         retval = wait_event_interruptible(evdev->wait,
361                 client->head != client->tail || !evdev->exist);
362         if (retval)
363                 return retval;
364
365         if (!evdev->exist)
366                 return -ENODEV;
367
368         while (retval + input_event_size() <= count &&
369                evdev_fetch_next_event(client, &event)) {
370
371                 if (input_event_to_user(buffer + retval, &event))
372                         return -EFAULT;
373
374                 retval += input_event_size();
375         }
376
377         return retval;
378 }
379
380 /* No kernel lock - fine */
381 static unsigned int evdev_poll(struct file *file, poll_table *wait)
382 {
383         struct evdev_client *client = file->private_data;
384         struct evdev *evdev = client->evdev;
385
386         poll_wait(file, &evdev->wait, wait);
387         return ((client->head == client->tail) ? 0 : (POLLIN | POLLRDNORM)) |
388                 (evdev->exist ? 0 : (POLLHUP | POLLERR));
389 }
390
391 #ifdef CONFIG_COMPAT
392
393 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
394 #define BITS_TO_LONGS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1)
395
396 #ifdef __BIG_ENDIAN
397 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
398                         unsigned int maxlen, void __user *p, int compat)
399 {
400         int len, i;
401
402         if (compat) {
403                 len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t);
404                 if (len > maxlen)
405                         len = maxlen;
406
407                 for (i = 0; i < len / sizeof(compat_long_t); i++)
408                         if (copy_to_user((compat_long_t __user *) p + i,
409                                          (compat_long_t *) bits +
410                                                 i + 1 - ((i % 2) << 1),
411                                          sizeof(compat_long_t)))
412                                 return -EFAULT;
413         } else {
414                 len = BITS_TO_LONGS(maxbit) * sizeof(long);
415                 if (len > maxlen)
416                         len = maxlen;
417
418                 if (copy_to_user(p, bits, len))
419                         return -EFAULT;
420         }
421
422         return len;
423 }
424 #else
425 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
426                         unsigned int maxlen, void __user *p, int compat)
427 {
428         int len = compat ?
429                         BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t) :
430                         BITS_TO_LONGS(maxbit) * sizeof(long);
431
432         if (len > maxlen)
433                 len = maxlen;
434
435         return copy_to_user(p, bits, len) ? -EFAULT : len;
436 }
437 #endif /* __BIG_ENDIAN */
438
439 #else
440
441 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
442                         unsigned int maxlen, void __user *p, int compat)
443 {
444         int len = BITS_TO_LONGS(maxbit) * sizeof(long);
445
446         if (len > maxlen)
447                 len = maxlen;
448
449         return copy_to_user(p, bits, len) ? -EFAULT : len;
450 }
451
452 #endif /* CONFIG_COMPAT */
453
454 static int str_to_user(const char *str, unsigned int maxlen, void __user *p)
455 {
456         int len;
457
458         if (!str)
459                 return -ENOENT;
460
461         len = strlen(str) + 1;
462         if (len > maxlen)
463                 len = maxlen;
464
465         return copy_to_user(p, str, len) ? -EFAULT : len;
466 }
467
468 #define OLD_KEY_MAX     0x1ff
469 static int handle_eviocgbit(struct input_dev *dev, unsigned int cmd, void __user *p, int compat_mode)
470 {
471         static unsigned long keymax_warn_time;
472         unsigned long *bits;
473         int len;
474
475         switch (_IOC_NR(cmd) & EV_MAX) {
476
477         case      0: bits = dev->evbit;  len = EV_MAX;  break;
478         case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
479         case EV_REL: bits = dev->relbit; len = REL_MAX; break;
480         case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
481         case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break;
482         case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
483         case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
484         case EV_FF:  bits = dev->ffbit;  len = FF_MAX;  break;
485         case EV_SW:  bits = dev->swbit;  len = SW_MAX;  break;
486         default: return -EINVAL;
487         }
488
489         /*
490          * Work around bugs in userspace programs that like to do
491          * EVIOCGBIT(EV_KEY, KEY_MAX) and not realize that 'len'
492          * should be in bytes, not in bits.
493          */
494         if ((_IOC_NR(cmd) & EV_MAX) == EV_KEY && _IOC_SIZE(cmd) == OLD_KEY_MAX) {
495                 len = OLD_KEY_MAX;
496                 if (printk_timed_ratelimit(&keymax_warn_time, 10 * 1000))
497                         printk(KERN_WARNING
498                                 "evdev.c(EVIOCGBIT): Suspicious buffer size %u, "
499                                 "limiting output to %zu bytes. See "
500                                 "http://userweb.kernel.org/~dtor/eviocgbit-bug.html\n",
501                                 OLD_KEY_MAX,
502                                 BITS_TO_LONGS(OLD_KEY_MAX) * sizeof(long));
503         }
504
505         return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode);
506 }
507 #undef OLD_KEY_MAX
508
509 static long evdev_do_ioctl(struct file *file, unsigned int cmd,
510                            void __user *p, int compat_mode)
511 {
512         struct evdev_client *client = file->private_data;
513         struct evdev *evdev = client->evdev;
514         struct input_dev *dev = evdev->handle.dev;
515         struct input_absinfo abs;
516         struct ff_effect effect;
517         int __user *ip = (int __user *)p;
518         int i, t, u, v;
519         int error;
520
521         switch (cmd) {
522
523         case EVIOCGVERSION:
524                 return put_user(EV_VERSION, ip);
525
526         case EVIOCGID:
527                 if (copy_to_user(p, &dev->id, sizeof(struct input_id)))
528                         return -EFAULT;
529                 return 0;
530
531         case EVIOCGREP:
532                 if (!test_bit(EV_REP, dev->evbit))
533                         return -ENOSYS;
534                 if (put_user(dev->rep[REP_DELAY], ip))
535                         return -EFAULT;
536                 if (put_user(dev->rep[REP_PERIOD], ip + 1))
537                         return -EFAULT;
538                 return 0;
539
540         case EVIOCSREP:
541                 if (!test_bit(EV_REP, dev->evbit))
542                         return -ENOSYS;
543                 if (get_user(u, ip))
544                         return -EFAULT;
545                 if (get_user(v, ip + 1))
546                         return -EFAULT;
547
548                 input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u);
549                 input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v);
550
551                 return 0;
552
553         case EVIOCGKEYCODE:
554                 if (get_user(t, ip))
555                         return -EFAULT;
556
557                 error = input_get_keycode(dev, t, &v);
558                 if (error)
559                         return error;
560
561                 if (put_user(v, ip + 1))
562                         return -EFAULT;
563
564                 return 0;
565
566         case EVIOCSKEYCODE:
567                 if (get_user(t, ip) || get_user(v, ip + 1))
568                         return -EFAULT;
569
570                 return input_set_keycode(dev, t, v);
571
572         case EVIOCRMFF:
573                 return input_ff_erase(dev, (int)(unsigned long) p, file);
574
575         case EVIOCGEFFECTS:
576                 i = test_bit(EV_FF, dev->evbit) ?
577                                 dev->ff->max_effects : 0;
578                 if (put_user(i, ip))
579                         return -EFAULT;
580                 return 0;
581
582         case EVIOCGRAB:
583                 if (p)
584                         return evdev_grab(evdev, client);
585                 else
586                         return evdev_ungrab(evdev, client);
587
588         default:
589
590                 if (_IOC_TYPE(cmd) != 'E')
591                         return -EINVAL;
592
593                 if (_IOC_DIR(cmd) == _IOC_READ) {
594
595                         if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0, 0)))
596                                 return handle_eviocgbit(dev, cmd, p, compat_mode);
597
598                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0)))
599                                 return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd),
600                                                     p, compat_mode);
601
602                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0)))
603                                 return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd),
604                                                     p, compat_mode);
605
606                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0)))
607                                 return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd),
608                                                     p, compat_mode);
609
610                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0)))
611                                 return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd),
612                                                     p, compat_mode);
613
614                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0)))
615                                 return str_to_user(dev->name, _IOC_SIZE(cmd), p);
616
617                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0)))
618                                 return str_to_user(dev->phys, _IOC_SIZE(cmd), p);
619
620                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0)))
621                                 return str_to_user(dev->uniq, _IOC_SIZE(cmd), p);
622
623                         if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
624
625                                 t = _IOC_NR(cmd) & ABS_MAX;
626
627                                 abs.value = dev->abs[t];
628                                 abs.minimum = dev->absmin[t];
629                                 abs.maximum = dev->absmax[t];
630                                 abs.fuzz = dev->absfuzz[t];
631                                 abs.flat = dev->absflat[t];
632
633                                 if (copy_to_user(p, &abs, sizeof(struct input_absinfo)))
634                                         return -EFAULT;
635
636                                 return 0;
637                         }
638
639                 }
640
641                 if (_IOC_DIR(cmd) == _IOC_WRITE) {
642
643                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCSFF)) {
644
645                                 if (input_ff_effect_from_user(p, _IOC_SIZE(cmd), &effect))
646                                         return -EFAULT;
647
648                                 error = input_ff_upload(dev, &effect, file);
649
650                                 if (put_user(effect.id, &(((struct ff_effect __user *)p)->id)))
651                                         return -EFAULT;
652
653                                 return error;
654                         }
655
656                         if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
657
658                                 t = _IOC_NR(cmd) & ABS_MAX;
659
660                                 if (copy_from_user(&abs, p,
661                                                 sizeof(struct input_absinfo)))
662                                         return -EFAULT;
663
664                                 /*
665                                  * Take event lock to ensure that we are not
666                                  * changing device parameters in the middle
667                                  * of event.
668                                  */
669                                 spin_lock_irq(&dev->event_lock);
670
671                                 dev->abs[t] = abs.value;
672                                 dev->absmin[t] = abs.minimum;
673                                 dev->absmax[t] = abs.maximum;
674                                 dev->absfuzz[t] = abs.fuzz;
675                                 dev->absflat[t] = abs.flat;
676
677                                 spin_unlock_irq(&dev->event_lock);
678
679                                 return 0;
680                         }
681                 }
682         }
683         return -EINVAL;
684 }
685
686 static long evdev_ioctl_handler(struct file *file, unsigned int cmd,
687                                 void __user *p, int compat_mode)
688 {
689         struct evdev_client *client = file->private_data;
690         struct evdev *evdev = client->evdev;
691         int retval;
692
693         retval = mutex_lock_interruptible(&evdev->mutex);
694         if (retval)
695                 return retval;
696
697         if (!evdev->exist) {
698                 retval = -ENODEV;
699                 goto out;
700         }
701
702         retval = evdev_do_ioctl(file, cmd, p, compat_mode);
703
704  out:
705         mutex_unlock(&evdev->mutex);
706         return retval;
707 }
708
709 static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
710 {
711         return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0);
712 }
713
714 #ifdef CONFIG_COMPAT
715 static long evdev_ioctl_compat(struct file *file,
716                                 unsigned int cmd, unsigned long arg)
717 {
718         return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1);
719 }
720 #endif
721
722 static const struct file_operations evdev_fops = {
723         .owner          = THIS_MODULE,
724         .read           = evdev_read,
725         .write          = evdev_write,
726         .poll           = evdev_poll,
727         .open           = evdev_open,
728         .release        = evdev_release,
729         .unlocked_ioctl = evdev_ioctl,
730 #ifdef CONFIG_COMPAT
731         .compat_ioctl   = evdev_ioctl_compat,
732 #endif
733         .fasync         = evdev_fasync,
734         .flush          = evdev_flush
735 };
736
737 static int evdev_install_chrdev(struct evdev *evdev)
738 {
739         /*
740          * No need to do any locking here as calls to connect and
741          * disconnect are serialized by the input core
742          */
743         evdev_table[evdev->minor] = evdev;
744         return 0;
745 }
746
747 static void evdev_remove_chrdev(struct evdev *evdev)
748 {
749         /*
750          * Lock evdev table to prevent race with evdev_open()
751          */
752         mutex_lock(&evdev_table_mutex);
753         evdev_table[evdev->minor] = NULL;
754         mutex_unlock(&evdev_table_mutex);
755 }
756
757 /*
758  * Mark device non-existent. This disables writes, ioctls and
759  * prevents new users from opening the device. Already posted
760  * blocking reads will stay, however new ones will fail.
761  */
762 static void evdev_mark_dead(struct evdev *evdev)
763 {
764         mutex_lock(&evdev->mutex);
765         evdev->exist = 0;
766         mutex_unlock(&evdev->mutex);
767 }
768
769 static void evdev_cleanup(struct evdev *evdev)
770 {
771         struct input_handle *handle = &evdev->handle;
772
773         evdev_mark_dead(evdev);
774         evdev_hangup(evdev);
775         evdev_remove_chrdev(evdev);
776
777         /* evdev is marked dead so no one else accesses evdev->open */
778         if (evdev->open) {
779                 input_flush_device(handle, NULL);
780                 input_close_device(handle);
781         }
782 }
783
784 /*
785  * Create new evdev device. Note that input core serializes calls
786  * to connect and disconnect so we don't need to lock evdev_table here.
787  */
788 static int evdev_connect(struct input_handler *handler, struct input_dev *dev,
789                          const struct input_device_id *id)
790 {
791         struct evdev *evdev;
792         int minor;
793         int error;
794
795         for (minor = 0; minor < EVDEV_MINORS; minor++)
796                 if (!evdev_table[minor])
797                         break;
798
799         if (minor == EVDEV_MINORS) {
800                 printk(KERN_ERR "evdev: no more free evdev devices\n");
801                 return -ENFILE;
802         }
803
804         evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL);
805         if (!evdev)
806                 return -ENOMEM;
807
808         INIT_LIST_HEAD(&evdev->client_list);
809         spin_lock_init(&evdev->client_lock);
810         mutex_init(&evdev->mutex);
811         init_waitqueue_head(&evdev->wait);
812
813         snprintf(evdev->name, sizeof(evdev->name), "event%d", minor);
814         evdev->exist = 1;
815         evdev->minor = minor;
816
817         evdev->handle.dev = input_get_device(dev);
818         evdev->handle.name = evdev->name;
819         evdev->handle.handler = handler;
820         evdev->handle.private = evdev;
821
822         dev_set_name(&evdev->dev, evdev->name);
823         evdev->dev.devt = MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor);
824         evdev->dev.class = &input_class;
825         evdev->dev.parent = &dev->dev;
826         evdev->dev.release = evdev_free;
827         device_initialize(&evdev->dev);
828
829         error = input_register_handle(&evdev->handle);
830         if (error)
831                 goto err_free_evdev;
832
833         error = evdev_install_chrdev(evdev);
834         if (error)
835                 goto err_unregister_handle;
836
837         error = device_add(&evdev->dev);
838         if (error)
839                 goto err_cleanup_evdev;
840
841         return 0;
842
843  err_cleanup_evdev:
844         evdev_cleanup(evdev);
845  err_unregister_handle:
846         input_unregister_handle(&evdev->handle);
847  err_free_evdev:
848         put_device(&evdev->dev);
849         return error;
850 }
851
852 static void evdev_disconnect(struct input_handle *handle)
853 {
854         struct evdev *evdev = handle->private;
855
856         device_del(&evdev->dev);
857         evdev_cleanup(evdev);
858         input_unregister_handle(handle);
859         put_device(&evdev->dev);
860 }
861
862 static const struct input_device_id evdev_ids[] = {
863         { .driver_info = 1 },   /* Matches all devices */
864         { },                    /* Terminating zero entry */
865 };
866
867 MODULE_DEVICE_TABLE(input, evdev_ids);
868
869 static struct input_handler evdev_handler = {
870         .event          = evdev_event,
871         .connect        = evdev_connect,
872         .disconnect     = evdev_disconnect,
873         .fops           = &evdev_fops,
874         .minor          = EVDEV_MINOR_BASE,
875         .name           = "evdev",
876         .id_table       = evdev_ids,
877 };
878
879 static int __init evdev_init(void)
880 {
881         return input_register_handler(&evdev_handler);
882 }
883
884 static void __exit evdev_exit(void)
885 {
886         input_unregister_handler(&evdev_handler);
887 }
888
889 module_init(evdev_init);
890 module_exit(evdev_exit);
891
892 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
893 MODULE_DESCRIPTION("Input driver event char devices");
894 MODULE_LICENSE("GPL");