Linux 2.6.28-rc9
[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 <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_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 struct ff_periodic_effect_compat {
303         __u16 waveform;
304         __u16 period;
305         __s16 magnitude;
306         __s16 offset;
307         __u16 phase;
308
309         struct ff_envelope envelope;
310
311         __u32 custom_len;
312         compat_uptr_t custom_data;
313 };
314
315 struct ff_effect_compat {
316         __u16 type;
317         __s16 id;
318         __u16 direction;
319         struct ff_trigger trigger;
320         struct ff_replay replay;
321
322         union {
323                 struct ff_constant_effect constant;
324                 struct ff_ramp_effect ramp;
325                 struct ff_periodic_effect_compat periodic;
326                 struct ff_condition_effect condition[2]; /* One for each axis */
327                 struct ff_rumble_effect rumble;
328         } u;
329 };
330
331 /* Note to the author of this code: did it ever occur to
332    you why the ifdefs are needed? Think about it again. -AK */
333 #ifdef CONFIG_X86_64
334 #  define COMPAT_TEST is_compat_task()
335 #elif defined(CONFIG_IA64)
336 #  define COMPAT_TEST IS_IA32_PROCESS(task_pt_regs(current))
337 #elif defined(CONFIG_S390)
338 #  define COMPAT_TEST test_thread_flag(TIF_31BIT)
339 #elif defined(CONFIG_MIPS)
340 #  define COMPAT_TEST test_thread_flag(TIF_32BIT_ADDR)
341 #else
342 #  define COMPAT_TEST test_thread_flag(TIF_32BIT)
343 #endif
344
345 static inline size_t evdev_event_size(void)
346 {
347         return COMPAT_TEST ?
348                 sizeof(struct input_event_compat) : sizeof(struct input_event);
349 }
350
351 static int evdev_event_from_user(const char __user *buffer,
352                                  struct input_event *event)
353 {
354         if (COMPAT_TEST) {
355                 struct input_event_compat compat_event;
356
357                 if (copy_from_user(&compat_event, buffer,
358                                    sizeof(struct input_event_compat)))
359                         return -EFAULT;
360
361                 event->time.tv_sec = compat_event.time.tv_sec;
362                 event->time.tv_usec = compat_event.time.tv_usec;
363                 event->type = compat_event.type;
364                 event->code = compat_event.code;
365                 event->value = compat_event.value;
366
367         } else {
368                 if (copy_from_user(event, buffer, sizeof(struct input_event)))
369                         return -EFAULT;
370         }
371
372         return 0;
373 }
374
375 static int evdev_event_to_user(char __user *buffer,
376                                 const struct input_event *event)
377 {
378         if (COMPAT_TEST) {
379                 struct input_event_compat compat_event;
380
381                 compat_event.time.tv_sec = event->time.tv_sec;
382                 compat_event.time.tv_usec = event->time.tv_usec;
383                 compat_event.type = event->type;
384                 compat_event.code = event->code;
385                 compat_event.value = event->value;
386
387                 if (copy_to_user(buffer, &compat_event,
388                                  sizeof(struct input_event_compat)))
389                         return -EFAULT;
390
391         } else {
392                 if (copy_to_user(buffer, event, sizeof(struct input_event)))
393                         return -EFAULT;
394         }
395
396         return 0;
397 }
398
399 static int evdev_ff_effect_from_user(const char __user *buffer, size_t size,
400                                      struct ff_effect *effect)
401 {
402         if (COMPAT_TEST) {
403                 struct ff_effect_compat *compat_effect;
404
405                 if (size != sizeof(struct ff_effect_compat))
406                         return -EINVAL;
407
408                 /*
409                  * It so happens that the pointer which needs to be changed
410                  * is the last field in the structure, so we can copy the
411                  * whole thing and replace just the pointer.
412                  */
413
414                 compat_effect = (struct ff_effect_compat *)effect;
415
416                 if (copy_from_user(compat_effect, buffer,
417                                    sizeof(struct ff_effect_compat)))
418                         return -EFAULT;
419
420                 if (compat_effect->type == FF_PERIODIC &&
421                     compat_effect->u.periodic.waveform == FF_CUSTOM)
422                         effect->u.periodic.custom_data =
423                                 compat_ptr(compat_effect->u.periodic.custom_data);
424         } else {
425                 if (size != sizeof(struct ff_effect))
426                         return -EINVAL;
427
428                 if (copy_from_user(effect, buffer, sizeof(struct ff_effect)))
429                         return -EFAULT;
430         }
431
432         return 0;
433 }
434
435 #else
436
437 static inline size_t evdev_event_size(void)
438 {
439         return sizeof(struct input_event);
440 }
441
442 static int evdev_event_from_user(const char __user *buffer,
443                                  struct input_event *event)
444 {
445         if (copy_from_user(event, buffer, sizeof(struct input_event)))
446                 return -EFAULT;
447
448         return 0;
449 }
450
451 static int evdev_event_to_user(char __user *buffer,
452                                 const struct input_event *event)
453 {
454         if (copy_to_user(buffer, event, sizeof(struct input_event)))
455                 return -EFAULT;
456
457         return 0;
458 }
459
460 static int evdev_ff_effect_from_user(const char __user *buffer, size_t size,
461                                      struct ff_effect *effect)
462 {
463         if (size != sizeof(struct ff_effect))
464                 return -EINVAL;
465
466         if (copy_from_user(effect, buffer, sizeof(struct ff_effect)))
467                 return -EFAULT;
468
469         return 0;
470 }
471
472 #endif /* CONFIG_COMPAT */
473
474 static ssize_t evdev_write(struct file *file, const char __user *buffer,
475                            size_t count, loff_t *ppos)
476 {
477         struct evdev_client *client = file->private_data;
478         struct evdev *evdev = client->evdev;
479         struct input_event event;
480         int retval;
481
482         retval = mutex_lock_interruptible(&evdev->mutex);
483         if (retval)
484                 return retval;
485
486         if (!evdev->exist) {
487                 retval = -ENODEV;
488                 goto out;
489         }
490
491         while (retval < count) {
492
493                 if (evdev_event_from_user(buffer + retval, &event)) {
494                         retval = -EFAULT;
495                         goto out;
496                 }
497
498                 input_inject_event(&evdev->handle,
499                                    event.type, event.code, event.value);
500                 retval += evdev_event_size();
501         }
502
503  out:
504         mutex_unlock(&evdev->mutex);
505         return retval;
506 }
507
508 static int evdev_fetch_next_event(struct evdev_client *client,
509                                   struct input_event *event)
510 {
511         int have_event;
512
513         spin_lock_irq(&client->buffer_lock);
514
515         have_event = client->head != client->tail;
516         if (have_event) {
517                 *event = client->buffer[client->tail++];
518                 client->tail &= EVDEV_BUFFER_SIZE - 1;
519         }
520
521         spin_unlock_irq(&client->buffer_lock);
522
523         return have_event;
524 }
525
526 static ssize_t evdev_read(struct file *file, char __user *buffer,
527                           size_t count, loff_t *ppos)
528 {
529         struct evdev_client *client = file->private_data;
530         struct evdev *evdev = client->evdev;
531         struct input_event event;
532         int retval;
533
534         if (count < evdev_event_size())
535                 return -EINVAL;
536
537         if (client->head == client->tail && evdev->exist &&
538             (file->f_flags & O_NONBLOCK))
539                 return -EAGAIN;
540
541         retval = wait_event_interruptible(evdev->wait,
542                 client->head != client->tail || !evdev->exist);
543         if (retval)
544                 return retval;
545
546         if (!evdev->exist)
547                 return -ENODEV;
548
549         while (retval + evdev_event_size() <= count &&
550                evdev_fetch_next_event(client, &event)) {
551
552                 if (evdev_event_to_user(buffer + retval, &event))
553                         return -EFAULT;
554
555                 retval += evdev_event_size();
556         }
557
558         return retval;
559 }
560
561 /* No kernel lock - fine */
562 static unsigned int evdev_poll(struct file *file, poll_table *wait)
563 {
564         struct evdev_client *client = file->private_data;
565         struct evdev *evdev = client->evdev;
566
567         poll_wait(file, &evdev->wait, wait);
568         return ((client->head == client->tail) ? 0 : (POLLIN | POLLRDNORM)) |
569                 (evdev->exist ? 0 : (POLLHUP | POLLERR));
570 }
571
572 #ifdef CONFIG_COMPAT
573
574 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
575 #define BITS_TO_LONGS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1)
576
577 #ifdef __BIG_ENDIAN
578 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
579                         unsigned int maxlen, void __user *p, int compat)
580 {
581         int len, i;
582
583         if (compat) {
584                 len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t);
585                 if (len > maxlen)
586                         len = maxlen;
587
588                 for (i = 0; i < len / sizeof(compat_long_t); i++)
589                         if (copy_to_user((compat_long_t __user *) p + i,
590                                          (compat_long_t *) bits +
591                                                 i + 1 - ((i % 2) << 1),
592                                          sizeof(compat_long_t)))
593                                 return -EFAULT;
594         } else {
595                 len = BITS_TO_LONGS(maxbit) * sizeof(long);
596                 if (len > maxlen)
597                         len = maxlen;
598
599                 if (copy_to_user(p, bits, len))
600                         return -EFAULT;
601         }
602
603         return len;
604 }
605 #else
606 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
607                         unsigned int maxlen, void __user *p, int compat)
608 {
609         int len = compat ?
610                         BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t) :
611                         BITS_TO_LONGS(maxbit) * sizeof(long);
612
613         if (len > maxlen)
614                 len = maxlen;
615
616         return copy_to_user(p, bits, len) ? -EFAULT : len;
617 }
618 #endif /* __BIG_ENDIAN */
619
620 #else
621
622 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
623                         unsigned int maxlen, void __user *p, int compat)
624 {
625         int len = BITS_TO_LONGS(maxbit) * sizeof(long);
626
627         if (len > maxlen)
628                 len = maxlen;
629
630         return copy_to_user(p, bits, len) ? -EFAULT : len;
631 }
632
633 #endif /* CONFIG_COMPAT */
634
635 static int str_to_user(const char *str, unsigned int maxlen, void __user *p)
636 {
637         int len;
638
639         if (!str)
640                 return -ENOENT;
641
642         len = strlen(str) + 1;
643         if (len > maxlen)
644                 len = maxlen;
645
646         return copy_to_user(p, str, len) ? -EFAULT : len;
647 }
648
649 #define OLD_KEY_MAX     0x1ff
650 static int handle_eviocgbit(struct input_dev *dev, unsigned int cmd, void __user *p, int compat_mode)
651 {
652         static unsigned long keymax_warn_time;
653         unsigned long *bits;
654         int len;
655
656         switch (_IOC_NR(cmd) & EV_MAX) {
657
658         case      0: bits = dev->evbit;  len = EV_MAX;  break;
659         case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
660         case EV_REL: bits = dev->relbit; len = REL_MAX; break;
661         case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
662         case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break;
663         case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
664         case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
665         case EV_FF:  bits = dev->ffbit;  len = FF_MAX;  break;
666         case EV_SW:  bits = dev->swbit;  len = SW_MAX;  break;
667         default: return -EINVAL;
668         }
669
670         /*
671          * Work around bugs in userspace programs that like to do
672          * EVIOCGBIT(EV_KEY, KEY_MAX) and not realize that 'len'
673          * should be in bytes, not in bits.
674          */
675         if ((_IOC_NR(cmd) & EV_MAX) == EV_KEY && _IOC_SIZE(cmd) == OLD_KEY_MAX) {
676                 len = OLD_KEY_MAX;
677                 if (printk_timed_ratelimit(&keymax_warn_time, 10 * 1000))
678                         printk(KERN_WARNING
679                                 "evdev.c(EVIOCGBIT): Suspicious buffer size %u, "
680                                 "limiting output to %zu bytes. See "
681                                 "http://userweb.kernel.org/~dtor/eviocgbit-bug.html\n",
682                                 OLD_KEY_MAX,
683                                 BITS_TO_LONGS(OLD_KEY_MAX) * sizeof(long));
684         }
685
686         return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode);
687 }
688 #undef OLD_KEY_MAX
689
690 static long evdev_do_ioctl(struct file *file, unsigned int cmd,
691                            void __user *p, int compat_mode)
692 {
693         struct evdev_client *client = file->private_data;
694         struct evdev *evdev = client->evdev;
695         struct input_dev *dev = evdev->handle.dev;
696         struct input_absinfo abs;
697         struct ff_effect effect;
698         int __user *ip = (int __user *)p;
699         int i, t, u, v;
700         int error;
701
702         switch (cmd) {
703
704         case EVIOCGVERSION:
705                 return put_user(EV_VERSION, ip);
706
707         case EVIOCGID:
708                 if (copy_to_user(p, &dev->id, sizeof(struct input_id)))
709                         return -EFAULT;
710                 return 0;
711
712         case EVIOCGREP:
713                 if (!test_bit(EV_REP, dev->evbit))
714                         return -ENOSYS;
715                 if (put_user(dev->rep[REP_DELAY], ip))
716                         return -EFAULT;
717                 if (put_user(dev->rep[REP_PERIOD], ip + 1))
718                         return -EFAULT;
719                 return 0;
720
721         case EVIOCSREP:
722                 if (!test_bit(EV_REP, dev->evbit))
723                         return -ENOSYS;
724                 if (get_user(u, ip))
725                         return -EFAULT;
726                 if (get_user(v, ip + 1))
727                         return -EFAULT;
728
729                 input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u);
730                 input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v);
731
732                 return 0;
733
734         case EVIOCGKEYCODE:
735                 if (get_user(t, ip))
736                         return -EFAULT;
737
738                 error = input_get_keycode(dev, t, &v);
739                 if (error)
740                         return error;
741
742                 if (put_user(v, ip + 1))
743                         return -EFAULT;
744
745                 return 0;
746
747         case EVIOCSKEYCODE:
748                 if (get_user(t, ip) || get_user(v, ip + 1))
749                         return -EFAULT;
750
751                 return input_set_keycode(dev, t, v);
752
753         case EVIOCRMFF:
754                 return input_ff_erase(dev, (int)(unsigned long) p, file);
755
756         case EVIOCGEFFECTS:
757                 i = test_bit(EV_FF, dev->evbit) ?
758                                 dev->ff->max_effects : 0;
759                 if (put_user(i, ip))
760                         return -EFAULT;
761                 return 0;
762
763         case EVIOCGRAB:
764                 if (p)
765                         return evdev_grab(evdev, client);
766                 else
767                         return evdev_ungrab(evdev, client);
768
769         default:
770
771                 if (_IOC_TYPE(cmd) != 'E')
772                         return -EINVAL;
773
774                 if (_IOC_DIR(cmd) == _IOC_READ) {
775
776                         if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0, 0)))
777                                 return handle_eviocgbit(dev, cmd, p, compat_mode);
778
779                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0)))
780                                 return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd),
781                                                     p, compat_mode);
782
783                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0)))
784                                 return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd),
785                                                     p, compat_mode);
786
787                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0)))
788                                 return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd),
789                                                     p, compat_mode);
790
791                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0)))
792                                 return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd),
793                                                     p, compat_mode);
794
795                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0)))
796                                 return str_to_user(dev->name, _IOC_SIZE(cmd), p);
797
798                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0)))
799                                 return str_to_user(dev->phys, _IOC_SIZE(cmd), p);
800
801                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0)))
802                                 return str_to_user(dev->uniq, _IOC_SIZE(cmd), p);
803
804                         if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
805
806                                 t = _IOC_NR(cmd) & ABS_MAX;
807
808                                 abs.value = dev->abs[t];
809                                 abs.minimum = dev->absmin[t];
810                                 abs.maximum = dev->absmax[t];
811                                 abs.fuzz = dev->absfuzz[t];
812                                 abs.flat = dev->absflat[t];
813
814                                 if (copy_to_user(p, &abs, sizeof(struct input_absinfo)))
815                                         return -EFAULT;
816
817                                 return 0;
818                         }
819
820                 }
821
822                 if (_IOC_DIR(cmd) == _IOC_WRITE) {
823
824                         if (_IOC_NR(cmd) == _IOC_NR(EVIOCSFF)) {
825
826                                 if (evdev_ff_effect_from_user(p, _IOC_SIZE(cmd), &effect))
827                                         return -EFAULT;
828
829                                 error = input_ff_upload(dev, &effect, file);
830
831                                 if (put_user(effect.id, &(((struct ff_effect __user *)p)->id)))
832                                         return -EFAULT;
833
834                                 return error;
835                         }
836
837                         if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
838
839                                 t = _IOC_NR(cmd) & ABS_MAX;
840
841                                 if (copy_from_user(&abs, p,
842                                                 sizeof(struct input_absinfo)))
843                                         return -EFAULT;
844
845                                 /*
846                                  * Take event lock to ensure that we are not
847                                  * changing device parameters in the middle
848                                  * of event.
849                                  */
850                                 spin_lock_irq(&dev->event_lock);
851
852                                 dev->abs[t] = abs.value;
853                                 dev->absmin[t] = abs.minimum;
854                                 dev->absmax[t] = abs.maximum;
855                                 dev->absfuzz[t] = abs.fuzz;
856                                 dev->absflat[t] = abs.flat;
857
858                                 spin_unlock_irq(&dev->event_lock);
859
860                                 return 0;
861                         }
862                 }
863         }
864         return -EINVAL;
865 }
866
867 static long evdev_ioctl_handler(struct file *file, unsigned int cmd,
868                                 void __user *p, int compat_mode)
869 {
870         struct evdev_client *client = file->private_data;
871         struct evdev *evdev = client->evdev;
872         int retval;
873
874         retval = mutex_lock_interruptible(&evdev->mutex);
875         if (retval)
876                 return retval;
877
878         if (!evdev->exist) {
879                 retval = -ENODEV;
880                 goto out;
881         }
882
883         retval = evdev_do_ioctl(file, cmd, p, compat_mode);
884
885  out:
886         mutex_unlock(&evdev->mutex);
887         return retval;
888 }
889
890 static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
891 {
892         return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0);
893 }
894
895 #ifdef CONFIG_COMPAT
896 static long evdev_ioctl_compat(struct file *file,
897                                 unsigned int cmd, unsigned long arg)
898 {
899         return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1);
900 }
901 #endif
902
903 static const struct file_operations evdev_fops = {
904         .owner          = THIS_MODULE,
905         .read           = evdev_read,
906         .write          = evdev_write,
907         .poll           = evdev_poll,
908         .open           = evdev_open,
909         .release        = evdev_release,
910         .unlocked_ioctl = evdev_ioctl,
911 #ifdef CONFIG_COMPAT
912         .compat_ioctl   = evdev_ioctl_compat,
913 #endif
914         .fasync         = evdev_fasync,
915         .flush          = evdev_flush
916 };
917
918 static int evdev_install_chrdev(struct evdev *evdev)
919 {
920         /*
921          * No need to do any locking here as calls to connect and
922          * disconnect are serialized by the input core
923          */
924         evdev_table[evdev->minor] = evdev;
925         return 0;
926 }
927
928 static void evdev_remove_chrdev(struct evdev *evdev)
929 {
930         /*
931          * Lock evdev table to prevent race with evdev_open()
932          */
933         mutex_lock(&evdev_table_mutex);
934         evdev_table[evdev->minor] = NULL;
935         mutex_unlock(&evdev_table_mutex);
936 }
937
938 /*
939  * Mark device non-existent. This disables writes, ioctls and
940  * prevents new users from opening the device. Already posted
941  * blocking reads will stay, however new ones will fail.
942  */
943 static void evdev_mark_dead(struct evdev *evdev)
944 {
945         mutex_lock(&evdev->mutex);
946         evdev->exist = 0;
947         mutex_unlock(&evdev->mutex);
948 }
949
950 static void evdev_cleanup(struct evdev *evdev)
951 {
952         struct input_handle *handle = &evdev->handle;
953
954         evdev_mark_dead(evdev);
955         evdev_hangup(evdev);
956         evdev_remove_chrdev(evdev);
957
958         /* evdev is marked dead so no one else accesses evdev->open */
959         if (evdev->open) {
960                 input_flush_device(handle, NULL);
961                 input_close_device(handle);
962         }
963 }
964
965 /*
966  * Create new evdev device. Note that input core serializes calls
967  * to connect and disconnect so we don't need to lock evdev_table here.
968  */
969 static int evdev_connect(struct input_handler *handler, struct input_dev *dev,
970                          const struct input_device_id *id)
971 {
972         struct evdev *evdev;
973         int minor;
974         int error;
975
976         for (minor = 0; minor < EVDEV_MINORS; minor++)
977                 if (!evdev_table[minor])
978                         break;
979
980         if (minor == EVDEV_MINORS) {
981                 printk(KERN_ERR "evdev: no more free evdev devices\n");
982                 return -ENFILE;
983         }
984
985         evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL);
986         if (!evdev)
987                 return -ENOMEM;
988
989         INIT_LIST_HEAD(&evdev->client_list);
990         spin_lock_init(&evdev->client_lock);
991         mutex_init(&evdev->mutex);
992         init_waitqueue_head(&evdev->wait);
993
994         snprintf(evdev->name, sizeof(evdev->name), "event%d", minor);
995         evdev->exist = 1;
996         evdev->minor = minor;
997
998         evdev->handle.dev = input_get_device(dev);
999         evdev->handle.name = evdev->name;
1000         evdev->handle.handler = handler;
1001         evdev->handle.private = evdev;
1002
1003         strlcpy(evdev->dev.bus_id, evdev->name, sizeof(evdev->dev.bus_id));
1004         evdev->dev.devt = MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor);
1005         evdev->dev.class = &input_class;
1006         evdev->dev.parent = &dev->dev;
1007         evdev->dev.release = evdev_free;
1008         device_initialize(&evdev->dev);
1009
1010         error = input_register_handle(&evdev->handle);
1011         if (error)
1012                 goto err_free_evdev;
1013
1014         error = evdev_install_chrdev(evdev);
1015         if (error)
1016                 goto err_unregister_handle;
1017
1018         error = device_add(&evdev->dev);
1019         if (error)
1020                 goto err_cleanup_evdev;
1021
1022         return 0;
1023
1024  err_cleanup_evdev:
1025         evdev_cleanup(evdev);
1026  err_unregister_handle:
1027         input_unregister_handle(&evdev->handle);
1028  err_free_evdev:
1029         put_device(&evdev->dev);
1030         return error;
1031 }
1032
1033 static void evdev_disconnect(struct input_handle *handle)
1034 {
1035         struct evdev *evdev = handle->private;
1036
1037         device_del(&evdev->dev);
1038         evdev_cleanup(evdev);
1039         input_unregister_handle(handle);
1040         put_device(&evdev->dev);
1041 }
1042
1043 static const struct input_device_id evdev_ids[] = {
1044         { .driver_info = 1 },   /* Matches all devices */
1045         { },                    /* Terminating zero entry */
1046 };
1047
1048 MODULE_DEVICE_TABLE(input, evdev_ids);
1049
1050 static struct input_handler evdev_handler = {
1051         .event          = evdev_event,
1052         .connect        = evdev_connect,
1053         .disconnect     = evdev_disconnect,
1054         .fops           = &evdev_fops,
1055         .minor          = EVDEV_MINOR_BASE,
1056         .name           = "evdev",
1057         .id_table       = evdev_ids,
1058 };
1059
1060 static int __init evdev_init(void)
1061 {
1062         return input_register_handler(&evdev_handler);
1063 }
1064
1065 static void __exit evdev_exit(void)
1066 {
1067         input_unregister_handler(&evdev_handler);
1068 }
1069
1070 module_init(evdev_init);
1071 module_exit(evdev_exit);
1072
1073 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
1074 MODULE_DESCRIPTION("Input driver event char devices");
1075 MODULE_LICENSE("GPL");