99562cee827e7c6af548ec2f889b3fc769dd9213
[sfrench/cifs-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 <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         kfree(evdev);
128 }
129
130 /*
131  * Grabs an event device (along with underlying input device).
132  * This function is called with evdev->mutex taken.
133  */
134 static int evdev_grab(struct evdev *evdev, struct evdev_client *client)
135 {
136         int error;
137
138         if (evdev->grab)
139                 return -EBUSY;
140
141         error = input_grab_device(&evdev->handle);
142         if (error)
143                 return error;
144
145         rcu_assign_pointer(evdev->grab, client);
146         synchronize_rcu();
147
148         return 0;
149 }
150
151 static int evdev_ungrab(struct evdev *evdev, struct evdev_client *client)
152 {
153         if (evdev->grab != client)
154                 return  -EINVAL;
155
156         rcu_assign_pointer(evdev->grab, NULL);
157         synchronize_rcu();
158         input_release_device(&evdev->handle);
159
160         return 0;
161 }
162
163 static void evdev_attach_client(struct evdev *evdev,
164                                 struct evdev_client *client)
165 {
166         spin_lock(&evdev->client_lock);
167         list_add_tail_rcu(&client->node, &evdev->client_list);
168         spin_unlock(&evdev->client_lock);
169         synchronize_rcu();
170 }
171
172 static void evdev_detach_client(struct evdev *evdev,
173                                 struct evdev_client *client)
174 {
175         spin_lock(&evdev->client_lock);
176         list_del_rcu(&client->node);
177         spin_unlock(&evdev->client_lock);
178         synchronize_rcu();
179 }
180
181 static int evdev_open_device(struct evdev *evdev)
182 {
183         int retval;
184
185         retval = mutex_lock_interruptible(&evdev->mutex);
186         if (retval)
187                 return retval;
188
189         if (!evdev->exist)
190                 retval = -ENODEV;
191         else if (!evdev->open++) {
192                 retval = input_open_device(&evdev->handle);
193                 if (retval)
194                         evdev->open--;
195         }
196
197         mutex_unlock(&evdev->mutex);
198         return retval;
199 }
200
201 static void evdev_close_device(struct evdev *evdev)
202 {
203         mutex_lock(&evdev->mutex);
204
205         if (evdev->exist && !--evdev->open)
206                 input_close_device(&evdev->handle);
207
208         mutex_unlock(&evdev->mutex);
209 }
210
211 /*
212  * Wake up users waiting for IO so they can disconnect from
213  * dead device.
214  */
215 static void evdev_hangup(struct evdev *evdev)
216 {
217         struct evdev_client *client;
218
219         spin_lock(&evdev->client_lock);
220         list_for_each_entry(client, &evdev->client_list, node)
221                 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
222         spin_unlock(&evdev->client_lock);
223
224         wake_up_interruptible(&evdev->wait);
225 }
226
227 static int evdev_release(struct inode *inode, struct file *file)
228 {
229         struct evdev_client *client = file->private_data;
230         struct evdev *evdev = client->evdev;
231
232         mutex_lock(&evdev->mutex);
233         if (evdev->grab == client)
234                 evdev_ungrab(evdev, client);
235         mutex_unlock(&evdev->mutex);
236
237         evdev_fasync(-1, file, 0);
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 #ifdef CONFIG_COMPAT
294
295 struct input_event_compat {
296         struct compat_timeval time;
297         __u16 type;
298         __u16 code;
299         __s32 value;
300 };
301
302 /* Note to the author of this code: did it ever occur to
303    you why the ifdefs are needed? Think about it again. -AK */
304 #ifdef CONFIG_X86_64
305 #  define COMPAT_TEST is_compat_task()
306 #elif defined(CONFIG_IA64)
307 #  define COMPAT_TEST IS_IA32_PROCESS(task_pt_regs(current))
308 #elif defined(CONFIG_S390)
309 #  define COMPAT_TEST test_thread_flag(TIF_31BIT)
310 #elif defined(CONFIG_MIPS)
311 #  define COMPAT_TEST test_thread_flag(TIF_32BIT_ADDR)
312 #else
313 #  define COMPAT_TEST test_thread_flag(TIF_32BIT)
314 #endif
315
316 static inline size_t evdev_event_size(void)
317 {
318         return COMPAT_TEST ?
319                 sizeof(struct input_event_compat) : sizeof(struct input_event);
320 }
321
322 static int evdev_event_from_user(const char __user *buffer,
323                                  struct input_event *event)
324 {
325         if (COMPAT_TEST) {
326                 struct input_event_compat compat_event;
327
328                 if (copy_from_user(&compat_event, buffer,
329                                    sizeof(struct input_event_compat)))
330                         return -EFAULT;
331
332                 event->time.tv_sec = compat_event.time.tv_sec;
333                 event->time.tv_usec = compat_event.time.tv_usec;
334                 event->type = compat_event.type;
335                 event->code = compat_event.code;
336                 event->value = compat_event.value;
337
338         } else {
339                 if (copy_from_user(event, buffer, sizeof(struct input_event)))
340                         return -EFAULT;
341         }
342
343         return 0;
344 }
345
346 static int evdev_event_to_user(char __user *buffer,
347                                 const struct input_event *event)
348 {
349         if (COMPAT_TEST) {
350                 struct input_event_compat compat_event;
351
352                 compat_event.time.tv_sec = event->time.tv_sec;
353                 compat_event.time.tv_usec = event->time.tv_usec;
354                 compat_event.type = event->type;
355                 compat_event.code = event->code;
356                 compat_event.value = event->value;
357
358                 if (copy_to_user(buffer, &compat_event,
359                                  sizeof(struct input_event_compat)))
360                         return -EFAULT;
361
362         } else {
363                 if (copy_to_user(buffer, event, sizeof(struct input_event)))
364                         return -EFAULT;
365         }
366
367         return 0;
368 }
369
370 #else
371
372 static inline size_t evdev_event_size(void)
373 {
374         return sizeof(struct input_event);
375 }
376
377 static int evdev_event_from_user(const char __user *buffer,
378                                  struct input_event *event)
379 {
380         if (copy_from_user(event, buffer, sizeof(struct input_event)))
381                 return -EFAULT;
382
383         return 0;
384 }
385
386 static int evdev_event_to_user(char __user *buffer,
387                                 const struct input_event *event)
388 {
389         if (copy_to_user(buffer, event, sizeof(struct input_event)))
390                 return -EFAULT;
391
392         return 0;
393 }
394
395 #endif /* CONFIG_COMPAT */
396
397 static ssize_t evdev_write(struct file *file, const char __user *buffer,
398                            size_t count, loff_t *ppos)
399 {
400         struct evdev_client *client = file->private_data;
401         struct evdev *evdev = client->evdev;
402         struct input_event event;
403         int retval;
404
405         retval = mutex_lock_interruptible(&evdev->mutex);
406         if (retval)
407                 return retval;
408
409         if (!evdev->exist) {
410                 retval = -ENODEV;
411                 goto out;
412         }
413
414         while (retval < count) {
415
416                 if (evdev_event_from_user(buffer + retval, &event)) {
417                         retval = -EFAULT;
418                         goto out;
419                 }
420
421                 input_inject_event(&evdev->handle,
422                                    event.type, event.code, event.value);
423                 retval += evdev_event_size();
424         }
425
426  out:
427         mutex_unlock(&evdev->mutex);
428         return retval;
429 }
430
431 static int evdev_fetch_next_event(struct evdev_client *client,
432                                   struct input_event *event)
433 {
434         int have_event;
435
436         spin_lock_irq(&client->buffer_lock);
437
438         have_event = client->head != client->tail;
439         if (have_event) {
440                 *event = client->buffer[client->tail++];
441                 client->tail &= EVDEV_BUFFER_SIZE - 1;
442         }
443
444         spin_unlock_irq(&client->buffer_lock);
445
446         return have_event;
447 }
448
449 static ssize_t evdev_read(struct file *file, char __user *buffer,
450                           size_t count, loff_t *ppos)
451 {
452         struct evdev_client *client = file->private_data;
453         struct evdev *evdev = client->evdev;
454         struct input_event event;
455         int retval;
456
457         if (count < evdev_event_size())
458                 return -EINVAL;
459
460         if (client->head == client->tail && evdev->exist &&
461             (file->f_flags & O_NONBLOCK))
462                 return -EAGAIN;
463
464         retval = wait_event_interruptible(evdev->wait,
465                 client->head != client->tail || !evdev->exist);
466         if (retval)
467                 return retval;
468
469         if (!evdev->exist)
470                 return -ENODEV;
471
472         while (retval + evdev_event_size() <= count &&
473                evdev_fetch_next_event(client, &event)) {
474
475                 if (evdev_event_to_user(buffer + retval, &event))
476                         return -EFAULT;
477
478                 retval += evdev_event_size();
479         }
480
481         return retval;
482 }
483
484 /* No kernel lock - fine */
485 static unsigned int evdev_poll(struct file *file, poll_table *wait)
486 {
487         struct evdev_client *client = file->private_data;
488         struct evdev *evdev = client->evdev;
489
490         poll_wait(file, &evdev->wait, wait);
491         return ((client->head == client->tail) ? 0 : (POLLIN | POLLRDNORM)) |
492                 (evdev->exist ? 0 : (POLLHUP | POLLERR));
493 }
494
495 #ifdef CONFIG_COMPAT
496
497 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
498 #define BITS_TO_LONGS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1)
499
500 #ifdef __BIG_ENDIAN
501 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
502                         unsigned int maxlen, void __user *p, int compat)
503 {
504         int len, i;
505
506         if (compat) {
507                 len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t);
508                 if (len > maxlen)
509                         len = maxlen;
510
511                 for (i = 0; i < len / sizeof(compat_long_t); i++)
512                         if (copy_to_user((compat_long_t __user *) p + i,
513                                          (compat_long_t *) bits +
514                                                 i + 1 - ((i % 2) << 1),
515                                          sizeof(compat_long_t)))
516                                 return -EFAULT;
517         } else {
518                 len = BITS_TO_LONGS(maxbit) * sizeof(long);
519                 if (len > maxlen)
520                         len = maxlen;
521
522                 if (copy_to_user(p, bits, len))
523                         return -EFAULT;
524         }
525
526         return len;
527 }
528 #else
529 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
530                         unsigned int maxlen, void __user *p, int compat)
531 {
532         int len = compat ?
533                         BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t) :
534                         BITS_TO_LONGS(maxbit) * sizeof(long);
535
536         if (len > maxlen)
537                 len = maxlen;
538
539         return copy_to_user(p, bits, len) ? -EFAULT : len;
540 }
541 #endif /* __BIG_ENDIAN */
542
543 #else
544
545 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
546                         unsigned int maxlen, void __user *p, int compat)
547 {
548         int len = BITS_TO_LONGS(maxbit) * sizeof(long);
549
550         if (len > maxlen)
551                 len = maxlen;
552
553         return copy_to_user(p, bits, len) ? -EFAULT : len;
554 }
555
556 #endif /* CONFIG_COMPAT */
557
558 static int str_to_user(const char *str, unsigned int maxlen, void __user *p)
559 {
560         int len;
561
562         if (!str)
563                 return -ENOENT;
564
565         len = strlen(str) + 1;
566         if (len > maxlen)
567                 len = maxlen;
568
569         return copy_to_user(p, str, len) ? -EFAULT : len;
570 }
571
572 static long evdev_do_ioctl(struct file *file, unsigned int cmd,
573                            void __user *p, int compat_mode)
574 {
575         struct evdev_client *client = file->private_data;
576         struct evdev *evdev = client->evdev;
577         struct input_dev *dev = evdev->handle.dev;
578         struct input_absinfo abs;
579         struct ff_effect effect;
580         int __user *ip = (int __user *)p;
581         int i, t, u, v;
582         int error;
583
584         switch (cmd) {
585
586         case EVIOCGVERSION:
587                 return put_user(EV_VERSION, ip);
588
589         case EVIOCGID:
590                 if (copy_to_user(p, &dev->id, sizeof(struct input_id)))
591                         return -EFAULT;
592                 return 0;
593
594         case EVIOCGREP:
595                 if (!test_bit(EV_REP, dev->evbit))
596                         return -ENOSYS;
597                 if (put_user(dev->rep[REP_DELAY], ip))
598                         return -EFAULT;
599                 if (put_user(dev->rep[REP_PERIOD], ip + 1))
600                         return -EFAULT;
601                 return 0;
602
603         case EVIOCSREP:
604                 if (!test_bit(EV_REP, dev->evbit))
605                         return -ENOSYS;
606                 if (get_user(u, ip))
607                         return -EFAULT;
608                 if (get_user(v, ip + 1))
609                         return -EFAULT;
610
611                 input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u);
612                 input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v);
613
614                 return 0;
615
616         case EVIOCGKEYCODE:
617                 if (get_user(t, ip))
618                         return -EFAULT;
619
620                 error = input_get_keycode(dev, t, &v);
621                 if (error)
622                         return error;
623
624                 if (put_user(v, ip + 1))
625                         return -EFAULT;
626
627                 return 0;
628
629         case EVIOCSKEYCODE:
630                 if (get_user(t, ip) || get_user(v, ip + 1))
631                         return -EFAULT;
632
633                 return input_set_keycode(dev, t, v);
634
635         case EVIOCSFF:
636                 if (copy_from_user(&effect, p, sizeof(effect)))
637                         return -EFAULT;
638
639                 error = input_ff_upload(dev, &effect, file);
640
641                 if (put_user(effect.id, &(((struct ff_effect __user *)p)->id)))
642                         return -EFAULT;
643
644                 return error;
645
646         case EVIOCRMFF:
647                 return input_ff_erase(dev, (int)(unsigned long) p, file);
648
649         case EVIOCGEFFECTS:
650                 i = test_bit(EV_FF, dev->evbit) ?
651                                 dev->ff->max_effects : 0;
652                 if (put_user(i, ip))
653                         return -EFAULT;
654                 return 0;
655
656         case EVIOCGRAB:
657                 if (p)
658                         return evdev_grab(evdev, client);
659                 else
660                         return evdev_ungrab(evdev, client);
661
662         default:
663
664                 if (_IOC_TYPE(cmd) != 'E')
665                         return -EINVAL;
666
667                 if (_IOC_DIR(cmd) == _IOC_READ) {
668
669                         if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0, 0))) {
670
671                                 unsigned long *bits;
672                                 int len;
673
674                                 switch (_IOC_NR(cmd) & EV_MAX) {
675
676                                 case      0: bits = dev->evbit;  len = EV_MAX;  break;
677                                 case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
678                                 case EV_REL: bits = dev->relbit; len = REL_MAX; break;
679                                 case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
680                                 case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break;
681                                 case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
682                                 case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
683                                 case EV_FF:  bits = dev->ffbit;  len = FF_MAX;  break;
684                                 case EV_SW:  bits = dev->swbit;  len = SW_MAX;  break;
685                                 default: return -EINVAL;
686                                 }
687                                 return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode);
688                         }
689
690                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0)))
691                                 return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd),
692                                                     p, compat_mode);
693
694                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0)))
695                                 return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd),
696                                                     p, compat_mode);
697
698                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0)))
699                                 return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd),
700                                                     p, compat_mode);
701
702                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0)))
703                                 return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd),
704                                                     p, compat_mode);
705
706                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0)))
707                                 return str_to_user(dev->name, _IOC_SIZE(cmd), p);
708
709                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0)))
710                                 return str_to_user(dev->phys, _IOC_SIZE(cmd), p);
711
712                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0)))
713                                 return str_to_user(dev->uniq, _IOC_SIZE(cmd), p);
714
715                         if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
716
717                                 t = _IOC_NR(cmd) & ABS_MAX;
718
719                                 abs.value = dev->abs[t];
720                                 abs.minimum = dev->absmin[t];
721                                 abs.maximum = dev->absmax[t];
722                                 abs.fuzz = dev->absfuzz[t];
723                                 abs.flat = dev->absflat[t];
724
725                                 if (copy_to_user(p, &abs, sizeof(struct input_absinfo)))
726                                         return -EFAULT;
727
728                                 return 0;
729                         }
730
731                 }
732
733                 if (_IOC_DIR(cmd) == _IOC_WRITE) {
734
735                         if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
736
737                                 t = _IOC_NR(cmd) & ABS_MAX;
738
739                                 if (copy_from_user(&abs, p,
740                                                 sizeof(struct input_absinfo)))
741                                         return -EFAULT;
742
743                                 /*
744                                  * Take event lock to ensure that we are not
745                                  * changing device parameters in the middle
746                                  * of event.
747                                  */
748                                 spin_lock_irq(&dev->event_lock);
749
750                                 dev->abs[t] = abs.value;
751                                 dev->absmin[t] = abs.minimum;
752                                 dev->absmax[t] = abs.maximum;
753                                 dev->absfuzz[t] = abs.fuzz;
754                                 dev->absflat[t] = abs.flat;
755
756                                 spin_unlock_irq(&dev->event_lock);
757
758                                 return 0;
759                         }
760                 }
761         }
762         return -EINVAL;
763 }
764
765 static long evdev_ioctl_handler(struct file *file, unsigned int cmd,
766                                 void __user *p, int compat_mode)
767 {
768         struct evdev_client *client = file->private_data;
769         struct evdev *evdev = client->evdev;
770         int retval;
771
772         retval = mutex_lock_interruptible(&evdev->mutex);
773         if (retval)
774                 return retval;
775
776         if (!evdev->exist) {
777                 retval = -ENODEV;
778                 goto out;
779         }
780
781         retval = evdev_do_ioctl(file, cmd, p, compat_mode);
782
783  out:
784         mutex_unlock(&evdev->mutex);
785         return retval;
786 }
787
788 static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
789 {
790         return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0);
791 }
792
793 #ifdef CONFIG_COMPAT
794 static long evdev_ioctl_compat(struct file *file,
795                                 unsigned int cmd, unsigned long arg)
796 {
797         return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1);
798 }
799 #endif
800
801 static const struct file_operations evdev_fops = {
802         .owner          = THIS_MODULE,
803         .read           = evdev_read,
804         .write          = evdev_write,
805         .poll           = evdev_poll,
806         .open           = evdev_open,
807         .release        = evdev_release,
808         .unlocked_ioctl = evdev_ioctl,
809 #ifdef CONFIG_COMPAT
810         .compat_ioctl   = evdev_ioctl_compat,
811 #endif
812         .fasync         = evdev_fasync,
813         .flush          = evdev_flush
814 };
815
816 static int evdev_install_chrdev(struct evdev *evdev)
817 {
818         /*
819          * No need to do any locking here as calls to connect and
820          * disconnect are serialized by the input core
821          */
822         evdev_table[evdev->minor] = evdev;
823         return 0;
824 }
825
826 static void evdev_remove_chrdev(struct evdev *evdev)
827 {
828         /*
829          * Lock evdev table to prevent race with evdev_open()
830          */
831         mutex_lock(&evdev_table_mutex);
832         evdev_table[evdev->minor] = NULL;
833         mutex_unlock(&evdev_table_mutex);
834 }
835
836 /*
837  * Mark device non-existent. This disables writes, ioctls and
838  * prevents new users from opening the device. Already posted
839  * blocking reads will stay, however new ones will fail.
840  */
841 static void evdev_mark_dead(struct evdev *evdev)
842 {
843         mutex_lock(&evdev->mutex);
844         evdev->exist = 0;
845         mutex_unlock(&evdev->mutex);
846 }
847
848 static void evdev_cleanup(struct evdev *evdev)
849 {
850         struct input_handle *handle = &evdev->handle;
851
852         evdev_mark_dead(evdev);
853         evdev_hangup(evdev);
854         evdev_remove_chrdev(evdev);
855
856         if (evdev->grab)
857                 evdev_ungrab(evdev, evdev->grab);
858
859         /* evdev is marked dead so no one else accesses evdev->open */
860         if (evdev->open) {
861                 input_flush_device(handle, NULL);
862                 input_close_device(handle);
863         }
864 }
865
866 /*
867  * Create new evdev device. Note that input core serializes calls
868  * to connect and disconnect so we don't need to lock evdev_table here.
869  */
870 static int evdev_connect(struct input_handler *handler, struct input_dev *dev,
871                          const struct input_device_id *id)
872 {
873         struct evdev *evdev;
874         int minor;
875         int error;
876
877         for (minor = 0; minor < EVDEV_MINORS; minor++)
878                 if (!evdev_table[minor])
879                         break;
880
881         if (minor == EVDEV_MINORS) {
882                 printk(KERN_ERR "evdev: no more free evdev devices\n");
883                 return -ENFILE;
884         }
885
886         evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL);
887         if (!evdev)
888                 return -ENOMEM;
889
890         INIT_LIST_HEAD(&evdev->client_list);
891         spin_lock_init(&evdev->client_lock);
892         mutex_init(&evdev->mutex);
893         init_waitqueue_head(&evdev->wait);
894
895         snprintf(evdev->name, sizeof(evdev->name), "event%d", minor);
896         evdev->exist = 1;
897         evdev->minor = minor;
898
899         evdev->handle.dev = dev;
900         evdev->handle.name = evdev->name;
901         evdev->handle.handler = handler;
902         evdev->handle.private = evdev;
903
904         strlcpy(evdev->dev.bus_id, evdev->name, sizeof(evdev->dev.bus_id));
905         evdev->dev.devt = MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor);
906         evdev->dev.class = &input_class;
907         evdev->dev.parent = &dev->dev;
908         evdev->dev.release = evdev_free;
909         device_initialize(&evdev->dev);
910
911         error = input_register_handle(&evdev->handle);
912         if (error)
913                 goto err_free_evdev;
914
915         error = evdev_install_chrdev(evdev);
916         if (error)
917                 goto err_unregister_handle;
918
919         error = device_add(&evdev->dev);
920         if (error)
921                 goto err_cleanup_evdev;
922
923         return 0;
924
925  err_cleanup_evdev:
926         evdev_cleanup(evdev);
927  err_unregister_handle:
928         input_unregister_handle(&evdev->handle);
929  err_free_evdev:
930         put_device(&evdev->dev);
931         return error;
932 }
933
934 static void evdev_disconnect(struct input_handle *handle)
935 {
936         struct evdev *evdev = handle->private;
937
938         device_del(&evdev->dev);
939         evdev_cleanup(evdev);
940         input_unregister_handle(handle);
941         put_device(&evdev->dev);
942 }
943
944 static const struct input_device_id evdev_ids[] = {
945         { .driver_info = 1 },   /* Matches all devices */
946         { },                    /* Terminating zero entry */
947 };
948
949 MODULE_DEVICE_TABLE(input, evdev_ids);
950
951 static struct input_handler evdev_handler = {
952         .event          = evdev_event,
953         .connect        = evdev_connect,
954         .disconnect     = evdev_disconnect,
955         .fops           = &evdev_fops,
956         .minor          = EVDEV_MINOR_BASE,
957         .name           = "evdev",
958         .id_table       = evdev_ids,
959 };
960
961 static int __init evdev_init(void)
962 {
963         return input_register_handler(&evdev_handler);
964 }
965
966 static void __exit evdev_exit(void)
967 {
968         input_unregister_handler(&evdev_handler);
969 }
970
971 module_init(evdev_init);
972 module_exit(evdev_exit);
973
974 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
975 MODULE_DESCRIPTION("Input driver event char devices");
976 MODULE_LICENSE("GPL");