Merge branch 'smsc47b397-new-id' into release
[linux-2.6] / 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 <linux/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_fasync(-1, file, 0);
239         evdev_detach_client(evdev, client);
240         kfree(client);
241
242         evdev_close_device(evdev);
243         put_device(&evdev->dev);
244
245         return 0;
246 }
247
248 static int evdev_open(struct inode *inode, struct file *file)
249 {
250         struct evdev *evdev;
251         struct evdev_client *client;
252         int i = iminor(inode) - EVDEV_MINOR_BASE;
253         int error;
254
255         if (i >= EVDEV_MINORS)
256                 return -ENODEV;
257
258         error = mutex_lock_interruptible(&evdev_table_mutex);
259         if (error)
260                 return error;
261         evdev = evdev_table[i];
262         if (evdev)
263                 get_device(&evdev->dev);
264         mutex_unlock(&evdev_table_mutex);
265
266         if (!evdev)
267                 return -ENODEV;
268
269         client = kzalloc(sizeof(struct evdev_client), GFP_KERNEL);
270         if (!client) {
271                 error = -ENOMEM;
272                 goto err_put_evdev;
273         }
274
275         spin_lock_init(&client->buffer_lock);
276         client->evdev = evdev;
277         evdev_attach_client(evdev, client);
278
279         error = evdev_open_device(evdev);
280         if (error)
281                 goto err_free_client;
282
283         file->private_data = client;
284         return 0;
285
286  err_free_client:
287         evdev_detach_client(evdev, client);
288         kfree(client);
289  err_put_evdev:
290         put_device(&evdev->dev);
291         return error;
292 }
293
294 #ifdef CONFIG_COMPAT
295
296 struct input_event_compat {
297         struct compat_timeval time;
298         __u16 type;
299         __u16 code;
300         __s32 value;
301 };
302
303 /* Note to the author of this code: did it ever occur to
304    you why the ifdefs are needed? Think about it again. -AK */
305 #ifdef CONFIG_X86_64
306 #  define COMPAT_TEST is_compat_task()
307 #elif defined(CONFIG_IA64)
308 #  define COMPAT_TEST IS_IA32_PROCESS(task_pt_regs(current))
309 #elif defined(CONFIG_S390)
310 #  define COMPAT_TEST test_thread_flag(TIF_31BIT)
311 #elif defined(CONFIG_MIPS)
312 #  define COMPAT_TEST test_thread_flag(TIF_32BIT_ADDR)
313 #else
314 #  define COMPAT_TEST test_thread_flag(TIF_32BIT)
315 #endif
316
317 static inline size_t evdev_event_size(void)
318 {
319         return COMPAT_TEST ?
320                 sizeof(struct input_event_compat) : sizeof(struct input_event);
321 }
322
323 static int evdev_event_from_user(const char __user *buffer,
324                                  struct input_event *event)
325 {
326         if (COMPAT_TEST) {
327                 struct input_event_compat compat_event;
328
329                 if (copy_from_user(&compat_event, buffer,
330                                    sizeof(struct input_event_compat)))
331                         return -EFAULT;
332
333                 event->time.tv_sec = compat_event.time.tv_sec;
334                 event->time.tv_usec = compat_event.time.tv_usec;
335                 event->type = compat_event.type;
336                 event->code = compat_event.code;
337                 event->value = compat_event.value;
338
339         } else {
340                 if (copy_from_user(event, buffer, sizeof(struct input_event)))
341                         return -EFAULT;
342         }
343
344         return 0;
345 }
346
347 static int evdev_event_to_user(char __user *buffer,
348                                 const struct input_event *event)
349 {
350         if (COMPAT_TEST) {
351                 struct input_event_compat compat_event;
352
353                 compat_event.time.tv_sec = event->time.tv_sec;
354                 compat_event.time.tv_usec = event->time.tv_usec;
355                 compat_event.type = event->type;
356                 compat_event.code = event->code;
357                 compat_event.value = event->value;
358
359                 if (copy_to_user(buffer, &compat_event,
360                                  sizeof(struct input_event_compat)))
361                         return -EFAULT;
362
363         } else {
364                 if (copy_to_user(buffer, event, sizeof(struct input_event)))
365                         return -EFAULT;
366         }
367
368         return 0;
369 }
370
371 #else
372
373 static inline size_t evdev_event_size(void)
374 {
375         return sizeof(struct input_event);
376 }
377
378 static int evdev_event_from_user(const char __user *buffer,
379                                  struct input_event *event)
380 {
381         if (copy_from_user(event, buffer, sizeof(struct input_event)))
382                 return -EFAULT;
383
384         return 0;
385 }
386
387 static int evdev_event_to_user(char __user *buffer,
388                                 const struct input_event *event)
389 {
390         if (copy_to_user(buffer, event, sizeof(struct input_event)))
391                 return -EFAULT;
392
393         return 0;
394 }
395
396 #endif /* CONFIG_COMPAT */
397
398 static ssize_t evdev_write(struct file *file, const char __user *buffer,
399                            size_t count, loff_t *ppos)
400 {
401         struct evdev_client *client = file->private_data;
402         struct evdev *evdev = client->evdev;
403         struct input_event event;
404         int retval;
405
406         retval = mutex_lock_interruptible(&evdev->mutex);
407         if (retval)
408                 return retval;
409
410         if (!evdev->exist) {
411                 retval = -ENODEV;
412                 goto out;
413         }
414
415         while (retval < count) {
416
417                 if (evdev_event_from_user(buffer + retval, &event)) {
418                         retval = -EFAULT;
419                         goto out;
420                 }
421
422                 input_inject_event(&evdev->handle,
423                                    event.type, event.code, event.value);
424                 retval += evdev_event_size();
425         }
426
427  out:
428         mutex_unlock(&evdev->mutex);
429         return retval;
430 }
431
432 static int evdev_fetch_next_event(struct evdev_client *client,
433                                   struct input_event *event)
434 {
435         int have_event;
436
437         spin_lock_irq(&client->buffer_lock);
438
439         have_event = client->head != client->tail;
440         if (have_event) {
441                 *event = client->buffer[client->tail++];
442                 client->tail &= EVDEV_BUFFER_SIZE - 1;
443         }
444
445         spin_unlock_irq(&client->buffer_lock);
446
447         return have_event;
448 }
449
450 static ssize_t evdev_read(struct file *file, char __user *buffer,
451                           size_t count, loff_t *ppos)
452 {
453         struct evdev_client *client = file->private_data;
454         struct evdev *evdev = client->evdev;
455         struct input_event event;
456         int retval;
457
458         if (count < evdev_event_size())
459                 return -EINVAL;
460
461         if (client->head == client->tail && evdev->exist &&
462             (file->f_flags & O_NONBLOCK))
463                 return -EAGAIN;
464
465         retval = wait_event_interruptible(evdev->wait,
466                 client->head != client->tail || !evdev->exist);
467         if (retval)
468                 return retval;
469
470         if (!evdev->exist)
471                 return -ENODEV;
472
473         while (retval + evdev_event_size() <= count &&
474                evdev_fetch_next_event(client, &event)) {
475
476                 if (evdev_event_to_user(buffer + retval, &event))
477                         return -EFAULT;
478
479                 retval += evdev_event_size();
480         }
481
482         return retval;
483 }
484
485 /* No kernel lock - fine */
486 static unsigned int evdev_poll(struct file *file, poll_table *wait)
487 {
488         struct evdev_client *client = file->private_data;
489         struct evdev *evdev = client->evdev;
490
491         poll_wait(file, &evdev->wait, wait);
492         return ((client->head == client->tail) ? 0 : (POLLIN | POLLRDNORM)) |
493                 (evdev->exist ? 0 : (POLLHUP | POLLERR));
494 }
495
496 #ifdef CONFIG_COMPAT
497
498 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
499 #define BITS_TO_LONGS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1)
500
501 #ifdef __BIG_ENDIAN
502 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
503                         unsigned int maxlen, void __user *p, int compat)
504 {
505         int len, i;
506
507         if (compat) {
508                 len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t);
509                 if (len > maxlen)
510                         len = maxlen;
511
512                 for (i = 0; i < len / sizeof(compat_long_t); i++)
513                         if (copy_to_user((compat_long_t __user *) p + i,
514                                          (compat_long_t *) bits +
515                                                 i + 1 - ((i % 2) << 1),
516                                          sizeof(compat_long_t)))
517                                 return -EFAULT;
518         } else {
519                 len = BITS_TO_LONGS(maxbit) * sizeof(long);
520                 if (len > maxlen)
521                         len = maxlen;
522
523                 if (copy_to_user(p, bits, len))
524                         return -EFAULT;
525         }
526
527         return len;
528 }
529 #else
530 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
531                         unsigned int maxlen, void __user *p, int compat)
532 {
533         int len = compat ?
534                         BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t) :
535                         BITS_TO_LONGS(maxbit) * sizeof(long);
536
537         if (len > maxlen)
538                 len = maxlen;
539
540         return copy_to_user(p, bits, len) ? -EFAULT : len;
541 }
542 #endif /* __BIG_ENDIAN */
543
544 #else
545
546 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
547                         unsigned int maxlen, void __user *p, int compat)
548 {
549         int len = BITS_TO_LONGS(maxbit) * sizeof(long);
550
551         if (len > maxlen)
552                 len = maxlen;
553
554         return copy_to_user(p, bits, len) ? -EFAULT : len;
555 }
556
557 #endif /* CONFIG_COMPAT */
558
559 static int str_to_user(const char *str, unsigned int maxlen, void __user *p)
560 {
561         int len;
562
563         if (!str)
564                 return -ENOENT;
565
566         len = strlen(str) + 1;
567         if (len > maxlen)
568                 len = maxlen;
569
570         return copy_to_user(p, str, len) ? -EFAULT : len;
571 }
572
573 static long evdev_do_ioctl(struct file *file, unsigned int cmd,
574                            void __user *p, int compat_mode)
575 {
576         struct evdev_client *client = file->private_data;
577         struct evdev *evdev = client->evdev;
578         struct input_dev *dev = evdev->handle.dev;
579         struct input_absinfo abs;
580         struct ff_effect effect;
581         int __user *ip = (int __user *)p;
582         int i, t, u, v;
583         int error;
584
585         switch (cmd) {
586
587         case EVIOCGVERSION:
588                 return put_user(EV_VERSION, ip);
589
590         case EVIOCGID:
591                 if (copy_to_user(p, &dev->id, sizeof(struct input_id)))
592                         return -EFAULT;
593                 return 0;
594
595         case EVIOCGREP:
596                 if (!test_bit(EV_REP, dev->evbit))
597                         return -ENOSYS;
598                 if (put_user(dev->rep[REP_DELAY], ip))
599                         return -EFAULT;
600                 if (put_user(dev->rep[REP_PERIOD], ip + 1))
601                         return -EFAULT;
602                 return 0;
603
604         case EVIOCSREP:
605                 if (!test_bit(EV_REP, dev->evbit))
606                         return -ENOSYS;
607                 if (get_user(u, ip))
608                         return -EFAULT;
609                 if (get_user(v, ip + 1))
610                         return -EFAULT;
611
612                 input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u);
613                 input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v);
614
615                 return 0;
616
617         case EVIOCGKEYCODE:
618                 if (get_user(t, ip))
619                         return -EFAULT;
620
621                 error = input_get_keycode(dev, t, &v);
622                 if (error)
623                         return error;
624
625                 if (put_user(v, ip + 1))
626                         return -EFAULT;
627
628                 return 0;
629
630         case EVIOCSKEYCODE:
631                 if (get_user(t, ip) || get_user(v, ip + 1))
632                         return -EFAULT;
633
634                 return input_set_keycode(dev, t, v);
635
636         case EVIOCSFF:
637                 if (copy_from_user(&effect, p, sizeof(effect)))
638                         return -EFAULT;
639
640                 error = input_ff_upload(dev, &effect, file);
641
642                 if (put_user(effect.id, &(((struct ff_effect __user *)p)->id)))
643                         return -EFAULT;
644
645                 return error;
646
647         case EVIOCRMFF:
648                 return input_ff_erase(dev, (int)(unsigned long) p, file);
649
650         case EVIOCGEFFECTS:
651                 i = test_bit(EV_FF, dev->evbit) ?
652                                 dev->ff->max_effects : 0;
653                 if (put_user(i, ip))
654                         return -EFAULT;
655                 return 0;
656
657         case EVIOCGRAB:
658                 if (p)
659                         return evdev_grab(evdev, client);
660                 else
661                         return evdev_ungrab(evdev, client);
662
663         default:
664
665                 if (_IOC_TYPE(cmd) != 'E')
666                         return -EINVAL;
667
668                 if (_IOC_DIR(cmd) == _IOC_READ) {
669
670                         if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0, 0))) {
671
672                                 unsigned long *bits;
673                                 int len;
674
675                                 switch (_IOC_NR(cmd) & EV_MAX) {
676
677                                 case      0: bits = dev->evbit;  len = EV_MAX;  break;
678                                 case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
679                                 case EV_REL: bits = dev->relbit; len = REL_MAX; break;
680                                 case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
681                                 case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break;
682                                 case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
683                                 case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
684                                 case EV_FF:  bits = dev->ffbit;  len = FF_MAX;  break;
685                                 case EV_SW:  bits = dev->swbit;  len = SW_MAX;  break;
686                                 default: return -EINVAL;
687                                 }
688                                 return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode);
689                         }
690
691                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0)))
692                                 return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd),
693                                                     p, compat_mode);
694
695                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0)))
696                                 return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd),
697                                                     p, compat_mode);
698
699                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0)))
700                                 return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd),
701                                                     p, compat_mode);
702
703                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0)))
704                                 return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd),
705                                                     p, compat_mode);
706
707                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0)))
708                                 return str_to_user(dev->name, _IOC_SIZE(cmd), p);
709
710                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0)))
711                                 return str_to_user(dev->phys, _IOC_SIZE(cmd), p);
712
713                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0)))
714                                 return str_to_user(dev->uniq, _IOC_SIZE(cmd), p);
715
716                         if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
717
718                                 t = _IOC_NR(cmd) & ABS_MAX;
719
720                                 abs.value = dev->abs[t];
721                                 abs.minimum = dev->absmin[t];
722                                 abs.maximum = dev->absmax[t];
723                                 abs.fuzz = dev->absfuzz[t];
724                                 abs.flat = dev->absflat[t];
725
726                                 if (copy_to_user(p, &abs, sizeof(struct input_absinfo)))
727                                         return -EFAULT;
728
729                                 return 0;
730                         }
731
732                 }
733
734                 if (_IOC_DIR(cmd) == _IOC_WRITE) {
735
736                         if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
737
738                                 t = _IOC_NR(cmd) & ABS_MAX;
739
740                                 if (copy_from_user(&abs, p,
741                                                 sizeof(struct input_absinfo)))
742                                         return -EFAULT;
743
744                                 /*
745                                  * Take event lock to ensure that we are not
746                                  * changing device parameters in the middle
747                                  * of event.
748                                  */
749                                 spin_lock_irq(&dev->event_lock);
750
751                                 dev->abs[t] = abs.value;
752                                 dev->absmin[t] = abs.minimum;
753                                 dev->absmax[t] = abs.maximum;
754                                 dev->absfuzz[t] = abs.fuzz;
755                                 dev->absflat[t] = abs.flat;
756
757                                 spin_unlock_irq(&dev->event_lock);
758
759                                 return 0;
760                         }
761                 }
762         }
763         return -EINVAL;
764 }
765
766 static long evdev_ioctl_handler(struct file *file, unsigned int cmd,
767                                 void __user *p, int compat_mode)
768 {
769         struct evdev_client *client = file->private_data;
770         struct evdev *evdev = client->evdev;
771         int retval;
772
773         retval = mutex_lock_interruptible(&evdev->mutex);
774         if (retval)
775                 return retval;
776
777         if (!evdev->exist) {
778                 retval = -ENODEV;
779                 goto out;
780         }
781
782         retval = evdev_do_ioctl(file, cmd, p, compat_mode);
783
784  out:
785         mutex_unlock(&evdev->mutex);
786         return retval;
787 }
788
789 static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
790 {
791         return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0);
792 }
793
794 #ifdef CONFIG_COMPAT
795 static long evdev_ioctl_compat(struct file *file,
796                                 unsigned int cmd, unsigned long arg)
797 {
798         return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1);
799 }
800 #endif
801
802 static const struct file_operations evdev_fops = {
803         .owner          = THIS_MODULE,
804         .read           = evdev_read,
805         .write          = evdev_write,
806         .poll           = evdev_poll,
807         .open           = evdev_open,
808         .release        = evdev_release,
809         .unlocked_ioctl = evdev_ioctl,
810 #ifdef CONFIG_COMPAT
811         .compat_ioctl   = evdev_ioctl_compat,
812 #endif
813         .fasync         = evdev_fasync,
814         .flush          = evdev_flush
815 };
816
817 static int evdev_install_chrdev(struct evdev *evdev)
818 {
819         /*
820          * No need to do any locking here as calls to connect and
821          * disconnect are serialized by the input core
822          */
823         evdev_table[evdev->minor] = evdev;
824         return 0;
825 }
826
827 static void evdev_remove_chrdev(struct evdev *evdev)
828 {
829         /*
830          * Lock evdev table to prevent race with evdev_open()
831          */
832         mutex_lock(&evdev_table_mutex);
833         evdev_table[evdev->minor] = NULL;
834         mutex_unlock(&evdev_table_mutex);
835 }
836
837 /*
838  * Mark device non-existent. This disables writes, ioctls and
839  * prevents new users from opening the device. Already posted
840  * blocking reads will stay, however new ones will fail.
841  */
842 static void evdev_mark_dead(struct evdev *evdev)
843 {
844         mutex_lock(&evdev->mutex);
845         evdev->exist = 0;
846         mutex_unlock(&evdev->mutex);
847 }
848
849 static void evdev_cleanup(struct evdev *evdev)
850 {
851         struct input_handle *handle = &evdev->handle;
852
853         evdev_mark_dead(evdev);
854         evdev_hangup(evdev);
855         evdev_remove_chrdev(evdev);
856
857         /* evdev is marked dead so no one else accesses evdev->open */
858         if (evdev->open) {
859                 input_flush_device(handle, NULL);
860                 input_close_device(handle);
861         }
862 }
863
864 /*
865  * Create new evdev device. Note that input core serializes calls
866  * to connect and disconnect so we don't need to lock evdev_table here.
867  */
868 static int evdev_connect(struct input_handler *handler, struct input_dev *dev,
869                          const struct input_device_id *id)
870 {
871         struct evdev *evdev;
872         int minor;
873         int error;
874
875         for (minor = 0; minor < EVDEV_MINORS; minor++)
876                 if (!evdev_table[minor])
877                         break;
878
879         if (minor == EVDEV_MINORS) {
880                 printk(KERN_ERR "evdev: no more free evdev devices\n");
881                 return -ENFILE;
882         }
883
884         evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL);
885         if (!evdev)
886                 return -ENOMEM;
887
888         INIT_LIST_HEAD(&evdev->client_list);
889         spin_lock_init(&evdev->client_lock);
890         mutex_init(&evdev->mutex);
891         init_waitqueue_head(&evdev->wait);
892
893         snprintf(evdev->name, sizeof(evdev->name), "event%d", minor);
894         evdev->exist = 1;
895         evdev->minor = minor;
896
897         evdev->handle.dev = input_get_device(dev);
898         evdev->handle.name = evdev->name;
899         evdev->handle.handler = handler;
900         evdev->handle.private = evdev;
901
902         strlcpy(evdev->dev.bus_id, evdev->name, sizeof(evdev->dev.bus_id));
903         evdev->dev.devt = MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor);
904         evdev->dev.class = &input_class;
905         evdev->dev.parent = &dev->dev;
906         evdev->dev.release = evdev_free;
907         device_initialize(&evdev->dev);
908
909         error = input_register_handle(&evdev->handle);
910         if (error)
911                 goto err_free_evdev;
912
913         error = evdev_install_chrdev(evdev);
914         if (error)
915                 goto err_unregister_handle;
916
917         error = device_add(&evdev->dev);
918         if (error)
919                 goto err_cleanup_evdev;
920
921         return 0;
922
923  err_cleanup_evdev:
924         evdev_cleanup(evdev);
925  err_unregister_handle:
926         input_unregister_handle(&evdev->handle);
927  err_free_evdev:
928         put_device(&evdev->dev);
929         return error;
930 }
931
932 static void evdev_disconnect(struct input_handle *handle)
933 {
934         struct evdev *evdev = handle->private;
935
936         device_del(&evdev->dev);
937         evdev_cleanup(evdev);
938         input_unregister_handle(handle);
939         put_device(&evdev->dev);
940 }
941
942 static const struct input_device_id evdev_ids[] = {
943         { .driver_info = 1 },   /* Matches all devices */
944         { },                    /* Terminating zero entry */
945 };
946
947 MODULE_DEVICE_TABLE(input, evdev_ids);
948
949 static struct input_handler evdev_handler = {
950         .event          = evdev_event,
951         .connect        = evdev_connect,
952         .disconnect     = evdev_disconnect,
953         .fops           = &evdev_fops,
954         .minor          = EVDEV_MINOR_BASE,
955         .name           = "evdev",
956         .id_table       = evdev_ids,
957 };
958
959 static int __init evdev_init(void)
960 {
961         return input_register_handler(&evdev_handler);
962 }
963
964 static void __exit evdev_exit(void)
965 {
966         input_unregister_handler(&evdev_handler);
967 }
968
969 module_init(evdev_init);
970 module_exit(evdev_exit);
971
972 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
973 MODULE_DESCRIPTION("Input driver event char devices");
974 MODULE_LICENSE("GPL");