[PATCH] EISA: tidy-up driver_register() return value
[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/smp_lock.h>
22 #include <linux/device.h>
23 #include <linux/compat.h>
24
25 struct evdev {
26         int exist;
27         int open;
28         int minor;
29         char name[16];
30         struct input_handle handle;
31         wait_queue_head_t wait;
32         struct evdev_list *grab;
33         struct list_head list;
34 };
35
36 struct evdev_list {
37         struct input_event buffer[EVDEV_BUFFER_SIZE];
38         int head;
39         int tail;
40         struct fasync_struct *fasync;
41         struct evdev *evdev;
42         struct list_head node;
43 };
44
45 static struct evdev *evdev_table[EVDEV_MINORS];
46
47 static void evdev_event(struct input_handle *handle, unsigned int type, unsigned int code, int value)
48 {
49         struct evdev *evdev = handle->private;
50         struct evdev_list *list;
51
52         if (evdev->grab) {
53                 list = evdev->grab;
54
55                 do_gettimeofday(&list->buffer[list->head].time);
56                 list->buffer[list->head].type = type;
57                 list->buffer[list->head].code = code;
58                 list->buffer[list->head].value = value;
59                 list->head = (list->head + 1) & (EVDEV_BUFFER_SIZE - 1);
60
61                 kill_fasync(&list->fasync, SIGIO, POLL_IN);
62         } else
63                 list_for_each_entry(list, &evdev->list, node) {
64
65                         do_gettimeofday(&list->buffer[list->head].time);
66                         list->buffer[list->head].type = type;
67                         list->buffer[list->head].code = code;
68                         list->buffer[list->head].value = value;
69                         list->head = (list->head + 1) & (EVDEV_BUFFER_SIZE - 1);
70
71                         kill_fasync(&list->fasync, SIGIO, POLL_IN);
72                 }
73
74         wake_up_interruptible(&evdev->wait);
75 }
76
77 static int evdev_fasync(int fd, struct file *file, int on)
78 {
79         int retval;
80         struct evdev_list *list = file->private_data;
81         retval = fasync_helper(fd, file, on, &list->fasync);
82         return retval < 0 ? retval : 0;
83 }
84
85 static int evdev_flush(struct file * file)
86 {
87         struct evdev_list *list = file->private_data;
88         if (!list->evdev->exist) return -ENODEV;
89         return input_flush_device(&list->evdev->handle, file);
90 }
91
92 static void evdev_free(struct evdev *evdev)
93 {
94         evdev_table[evdev->minor] = NULL;
95         kfree(evdev);
96 }
97
98 static int evdev_release(struct inode * inode, struct file * file)
99 {
100         struct evdev_list *list = file->private_data;
101
102         if (list->evdev->grab == list) {
103                 input_release_device(&list->evdev->handle);
104                 list->evdev->grab = NULL;
105         }
106
107         evdev_fasync(-1, file, 0);
108         list_del(&list->node);
109
110         if (!--list->evdev->open) {
111                 if (list->evdev->exist)
112                         input_close_device(&list->evdev->handle);
113                 else
114                         evdev_free(list->evdev);
115         }
116
117         kfree(list);
118         return 0;
119 }
120
121 static int evdev_open(struct inode * inode, struct file * file)
122 {
123         struct evdev_list *list;
124         int i = iminor(inode) - EVDEV_MINOR_BASE;
125         int accept_err;
126
127         if (i >= EVDEV_MINORS || !evdev_table[i] || !evdev_table[i]->exist)
128                 return -ENODEV;
129
130         if ((accept_err = input_accept_process(&(evdev_table[i]->handle), file)))
131                 return accept_err;
132
133         if (!(list = kmalloc(sizeof(struct evdev_list), GFP_KERNEL)))
134                 return -ENOMEM;
135         memset(list, 0, sizeof(struct evdev_list));
136
137         list->evdev = evdev_table[i];
138         list_add_tail(&list->node, &evdev_table[i]->list);
139         file->private_data = list;
140
141         if (!list->evdev->open++)
142                 if (list->evdev->exist)
143                         input_open_device(&list->evdev->handle);
144
145         return 0;
146 }
147
148 #ifdef CONFIG_COMPAT
149
150 struct input_event_compat {
151         struct compat_timeval time;
152         __u16 type;
153         __u16 code;
154         __s32 value;
155 };
156
157 /* Note to the author of this code: did it ever occur to
158    you why the ifdefs are needed? Think about it again. -AK */
159 #ifdef CONFIG_X86_64
160 #  define COMPAT_TEST is_compat_task()
161 #elif defined(CONFIG_IA64)
162 #  define COMPAT_TEST IS_IA32_PROCESS(task_pt_regs(current))
163 #elif defined(CONFIG_S390)
164 #  define COMPAT_TEST test_thread_flag(TIF_31BIT)
165 #elif defined(CONFIG_MIPS)
166 #  define COMPAT_TEST (current->thread.mflags & MF_32BIT_ADDR)
167 #else
168 #  define COMPAT_TEST test_thread_flag(TIF_32BIT)
169 #endif
170
171 static inline size_t evdev_event_size(void)
172 {
173         return COMPAT_TEST ?
174                 sizeof(struct input_event_compat) : sizeof(struct input_event);
175 }
176
177 static int evdev_event_from_user(const char __user *buffer, struct input_event *event)
178 {
179         if (COMPAT_TEST) {
180                 struct input_event_compat compat_event;
181
182                 if (copy_from_user(&compat_event, buffer, sizeof(struct input_event_compat)))
183                         return -EFAULT;
184
185                 event->time.tv_sec = compat_event.time.tv_sec;
186                 event->time.tv_usec = compat_event.time.tv_usec;
187                 event->type = compat_event.type;
188                 event->code = compat_event.code;
189                 event->value = compat_event.value;
190
191         } else {
192                 if (copy_from_user(event, buffer, sizeof(struct input_event)))
193                         return -EFAULT;
194         }
195
196         return 0;
197 }
198
199 static int evdev_event_to_user(char __user *buffer, const struct input_event *event)
200 {
201         if (COMPAT_TEST) {
202                 struct input_event_compat compat_event;
203
204                 compat_event.time.tv_sec = event->time.tv_sec;
205                 compat_event.time.tv_usec = event->time.tv_usec;
206                 compat_event.type = event->type;
207                 compat_event.code = event->code;
208                 compat_event.value = event->value;
209
210                 if (copy_to_user(buffer, &compat_event, sizeof(struct input_event_compat)))
211                         return -EFAULT;
212
213         } else {
214                 if (copy_to_user(buffer, event, sizeof(struct input_event)))
215                         return -EFAULT;
216         }
217
218         return 0;
219 }
220
221 #else
222
223 static inline size_t evdev_event_size(void)
224 {
225         return sizeof(struct input_event);
226 }
227
228 static int evdev_event_from_user(const char __user *buffer, struct input_event *event)
229 {
230         if (copy_from_user(event, buffer, sizeof(struct input_event)))
231                 return -EFAULT;
232
233         return 0;
234 }
235
236 static int evdev_event_to_user(char __user *buffer, const struct input_event *event)
237 {
238         if (copy_to_user(buffer, event, sizeof(struct input_event)))
239                 return -EFAULT;
240
241         return 0;
242 }
243
244 #endif /* CONFIG_COMPAT */
245
246 static ssize_t evdev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
247 {
248         struct evdev_list *list = file->private_data;
249         struct input_event event;
250         int retval = 0;
251
252         if (!list->evdev->exist)
253                 return -ENODEV;
254
255         while (retval < count) {
256
257                 if (evdev_event_from_user(buffer + retval, &event))
258                         return -EFAULT;
259                 input_event(list->evdev->handle.dev, event.type, event.code, event.value);
260                 retval += evdev_event_size();
261         }
262
263         return retval;
264 }
265
266 static ssize_t evdev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
267 {
268         struct evdev_list *list = file->private_data;
269         int retval;
270
271         if (count < evdev_event_size())
272                 return -EINVAL;
273
274         if (list->head == list->tail && list->evdev->exist && (file->f_flags & O_NONBLOCK))
275                 return -EAGAIN;
276
277         retval = wait_event_interruptible(list->evdev->wait,
278                 list->head != list->tail || (!list->evdev->exist));
279
280         if (retval)
281                 return retval;
282
283         if (!list->evdev->exist)
284                 return -ENODEV;
285
286         while (list->head != list->tail && retval + evdev_event_size() <= count) {
287
288                 struct input_event *event = (struct input_event *) list->buffer + list->tail;
289
290                 if (evdev_event_to_user(buffer + retval, event))
291                         return -EFAULT;
292
293                 list->tail = (list->tail + 1) & (EVDEV_BUFFER_SIZE - 1);
294                 retval += evdev_event_size();
295         }
296
297         return retval;
298 }
299
300 /* No kernel lock - fine */
301 static unsigned int evdev_poll(struct file *file, poll_table *wait)
302 {
303         struct evdev_list *list = file->private_data;
304         poll_wait(file, &list->evdev->wait, wait);
305         return ((list->head == list->tail) ? 0 : (POLLIN | POLLRDNORM)) |
306                 (list->evdev->exist ? 0 : (POLLHUP | POLLERR));
307 }
308
309 #ifdef CONFIG_COMPAT
310
311 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
312 #define NBITS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1)
313
314 #ifdef __BIG_ENDIAN
315 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
316                         unsigned int maxlen, void __user *p, int compat)
317 {
318         int len, i;
319
320         if (compat) {
321                 len = NBITS_COMPAT(maxbit) * sizeof(compat_long_t);
322                 if (len < maxlen)
323                         len = maxlen;
324
325                 for (i = 0; i < len / sizeof(compat_long_t); i++)
326                         if (copy_to_user((compat_long_t __user *) p + i,
327                                          (compat_long_t *) bits +
328                                                 i + 1 - ((i % 2) << 1),
329                                          sizeof(compat_long_t)))
330                                 return -EFAULT;
331         } else {
332                 len = NBITS(maxbit) * sizeof(long);
333                 if (len > maxlen)
334                         len = maxlen;
335
336                 if (copy_to_user(p, bits, len))
337                         return -EFAULT;
338         }
339
340         return len;
341 }
342 #else
343 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
344                         unsigned int maxlen, void __user *p, int compat)
345 {
346         int len = compat ?
347                         NBITS_COMPAT(maxbit) * sizeof(compat_long_t) :
348                         NBITS(maxbit) * sizeof(long);
349
350         if (len > maxlen)
351                 len = maxlen;
352
353         return copy_to_user(p, bits, len) ? -EFAULT : len;
354 }
355 #endif /* __BIG_ENDIAN */
356
357 #else
358
359 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
360                         unsigned int maxlen, void __user *p, int compat)
361 {
362         int len = NBITS(maxbit) * sizeof(long);
363
364         if (len > maxlen)
365                 len = maxlen;
366
367         return copy_to_user(p, bits, len) ? -EFAULT : len;
368 }
369
370 #endif /* CONFIG_COMPAT */
371
372 static int str_to_user(const char *str, unsigned int maxlen, void __user *p)
373 {
374         int len;
375
376         if (!str)
377                 return -ENOENT;
378
379         len = strlen(str) + 1;
380         if (len > maxlen)
381                 len = maxlen;
382
383         return copy_to_user(p, str, len) ? -EFAULT : len;
384 }
385
386 static long evdev_ioctl_handler(struct file *file, unsigned int cmd,
387                                 void __user *p, int compat_mode)
388 {
389         struct evdev_list *list = file->private_data;
390         struct evdev *evdev = list->evdev;
391         struct input_dev *dev = evdev->handle.dev;
392         struct input_absinfo abs;
393         int __user *ip = (int __user *)p;
394         int i, t, u, v;
395
396         if (!evdev->exist)
397                 return -ENODEV;
398
399         switch (cmd) {
400
401                 case EVIOCGVERSION:
402                         return put_user(EV_VERSION, ip);
403
404                 case EVIOCGID:
405                         if (copy_to_user(p, &dev->id, sizeof(struct input_id)))
406                                 return -EFAULT;
407
408                         return 0;
409
410                 case EVIOCGKEYCODE:
411                         if (get_user(t, ip))
412                                 return -EFAULT;
413                         if (t < 0 || t >= dev->keycodemax || !dev->keycodesize)
414                                 return -EINVAL;
415                         if (put_user(INPUT_KEYCODE(dev, t), ip + 1))
416                                 return -EFAULT;
417                         return 0;
418
419                 case EVIOCSKEYCODE:
420                         if (get_user(t, ip))
421                                 return -EFAULT;
422                         if (t < 0 || t >= dev->keycodemax || !dev->keycodesize)
423                                 return -EINVAL;
424                         if (get_user(v, ip + 1))
425                                 return -EFAULT;
426                         if (v < 0 || v > KEY_MAX)
427                                 return -EINVAL;
428                         if (dev->keycodesize < sizeof(v) && (v >> (dev->keycodesize * 8)))
429                                 return -EINVAL;
430
431                         u = SET_INPUT_KEYCODE(dev, t, v);
432                         clear_bit(u, dev->keybit);
433                         set_bit(v, dev->keybit);
434                         for (i = 0; i < dev->keycodemax; i++)
435                                 if (INPUT_KEYCODE(dev, i) == u)
436                                         set_bit(u, dev->keybit);
437
438                         return 0;
439
440                 case EVIOCSFF:
441                         if (dev->upload_effect) {
442                                 struct ff_effect effect;
443                                 int err;
444
445                                 if (copy_from_user(&effect, p, sizeof(effect)))
446                                         return -EFAULT;
447                                 err = dev->upload_effect(dev, &effect);
448                                 if (put_user(effect.id, &(((struct ff_effect __user *)p)->id)))
449                                         return -EFAULT;
450                                 return err;
451                         } else
452                                 return -ENOSYS;
453
454                 case EVIOCRMFF:
455                         if (!dev->erase_effect)
456                                 return -ENOSYS;
457
458                         return dev->erase_effect(dev, (int)(unsigned long) p);
459
460                 case EVIOCGEFFECTS:
461                         if (put_user(dev->ff_effects_max, ip))
462                                 return -EFAULT;
463                         return 0;
464
465                 case EVIOCGRAB:
466                         if (p) {
467                                 if (evdev->grab)
468                                         return -EBUSY;
469                                 if (input_grab_device(&evdev->handle))
470                                         return -EBUSY;
471                                 evdev->grab = list;
472                                 return 0;
473                         } else {
474                                 if (evdev->grab != list)
475                                         return -EINVAL;
476                                 input_release_device(&evdev->handle);
477                                 evdev->grab = NULL;
478                                 return 0;
479                         }
480
481                 default:
482
483                         if (_IOC_TYPE(cmd) != 'E')
484                                 return -EINVAL;
485
486                         if (_IOC_DIR(cmd) == _IOC_READ) {
487
488                                 if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0,0))) {
489
490                                         long *bits;
491                                         int len;
492
493                                         switch (_IOC_NR(cmd) & EV_MAX) {
494                                                 case      0: bits = dev->evbit;  len = EV_MAX;  break;
495                                                 case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
496                                                 case EV_REL: bits = dev->relbit; len = REL_MAX; break;
497                                                 case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
498                                                 case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break;
499                                                 case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
500                                                 case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
501                                                 case EV_FF:  bits = dev->ffbit;  len = FF_MAX;  break;
502                                                 case EV_SW:  bits = dev->swbit;  len = SW_MAX;  break;
503                                                 default: return -EINVAL;
504                                         }
505                                         return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode);
506                                 }
507
508                                 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0)))
509                                         return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd),
510                                                             p, compat_mode);
511
512                                 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0)))
513                                         return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd),
514                                                             p, compat_mode);
515
516                                 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0)))
517                                         return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd),
518                                                             p, compat_mode);
519
520                                 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0)))
521                                         return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd),
522                                                             p, compat_mode);
523
524                                 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0)))
525                                         return str_to_user(dev->name, _IOC_SIZE(cmd), p);
526
527                                 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0)))
528                                         return str_to_user(dev->phys, _IOC_SIZE(cmd), p);
529
530                                 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0)))
531                                         return str_to_user(dev->uniq, _IOC_SIZE(cmd), p);
532
533                                 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
534
535                                         int t = _IOC_NR(cmd) & ABS_MAX;
536
537                                         abs.value = dev->abs[t];
538                                         abs.minimum = dev->absmin[t];
539                                         abs.maximum = dev->absmax[t];
540                                         abs.fuzz = dev->absfuzz[t];
541                                         abs.flat = dev->absflat[t];
542
543                                         if (copy_to_user(p, &abs, sizeof(struct input_absinfo)))
544                                                 return -EFAULT;
545
546                                         return 0;
547                                 }
548
549                         }
550
551                         if (_IOC_DIR(cmd) == _IOC_WRITE) {
552
553                                 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
554
555                                         int t = _IOC_NR(cmd) & ABS_MAX;
556
557                                         if (copy_from_user(&abs, p, sizeof(struct input_absinfo)))
558                                                 return -EFAULT;
559
560                                         dev->abs[t] = abs.value;
561                                         dev->absmin[t] = abs.minimum;
562                                         dev->absmax[t] = abs.maximum;
563                                         dev->absfuzz[t] = abs.fuzz;
564                                         dev->absflat[t] = abs.flat;
565
566                                         return 0;
567                                 }
568                         }
569         }
570         return -EINVAL;
571 }
572
573 static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
574 {
575         return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0);
576 }
577
578 #ifdef CONFIG_COMPAT
579 static long evdev_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
580 {
581         return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1);
582 }
583 #endif
584
585 static struct file_operations evdev_fops = {
586         .owner =        THIS_MODULE,
587         .read =         evdev_read,
588         .write =        evdev_write,
589         .poll =         evdev_poll,
590         .open =         evdev_open,
591         .release =      evdev_release,
592         .unlocked_ioctl = evdev_ioctl,
593 #ifdef CONFIG_COMPAT
594         .compat_ioctl = evdev_ioctl_compat,
595 #endif
596         .fasync =       evdev_fasync,
597         .flush =        evdev_flush
598 };
599
600 static struct input_handle *evdev_connect(struct input_handler *handler, struct input_dev *dev, struct input_device_id *id)
601 {
602         struct evdev *evdev;
603         struct class_device *cdev;
604         int minor;
605
606         for (minor = 0; minor < EVDEV_MINORS && evdev_table[minor]; minor++);
607         if (minor == EVDEV_MINORS) {
608                 printk(KERN_ERR "evdev: no more free evdev devices\n");
609                 return NULL;
610         }
611
612         if (!(evdev = kmalloc(sizeof(struct evdev), GFP_KERNEL)))
613                 return NULL;
614         memset(evdev, 0, sizeof(struct evdev));
615
616         INIT_LIST_HEAD(&evdev->list);
617         init_waitqueue_head(&evdev->wait);
618
619         evdev->exist = 1;
620         evdev->minor = minor;
621         evdev->handle.dev = dev;
622         evdev->handle.name = evdev->name;
623         evdev->handle.handler = handler;
624         evdev->handle.private = evdev;
625         sprintf(evdev->name, "event%d", minor);
626
627         evdev_table[minor] = evdev;
628
629         cdev = class_device_create(&input_class, &dev->cdev,
630                         MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor),
631                         dev->cdev.dev, evdev->name);
632
633         /* temporary symlink to keep userspace happy */
634         sysfs_create_link(&input_class.subsys.kset.kobj, &cdev->kobj,
635                           evdev->name);
636
637         return &evdev->handle;
638 }
639
640 static void evdev_disconnect(struct input_handle *handle)
641 {
642         struct evdev *evdev = handle->private;
643         struct evdev_list *list;
644
645         sysfs_remove_link(&input_class.subsys.kset.kobj, evdev->name);
646         class_device_destroy(&input_class,
647                         MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + evdev->minor));
648         evdev->exist = 0;
649
650         if (evdev->open) {
651                 input_close_device(handle);
652                 wake_up_interruptible(&evdev->wait);
653                 list_for_each_entry(list, &evdev->list, node)
654                         kill_fasync(&list->fasync, SIGIO, POLL_HUP);
655         } else
656                 evdev_free(evdev);
657 }
658
659 static struct input_device_id evdev_ids[] = {
660         { .driver_info = 1 },   /* Matches all devices */
661         { },                    /* Terminating zero entry */
662 };
663
664 MODULE_DEVICE_TABLE(input, evdev_ids);
665
666 static struct input_handler evdev_handler = {
667         .event =        evdev_event,
668         .connect =      evdev_connect,
669         .disconnect =   evdev_disconnect,
670         .fops =         &evdev_fops,
671         .minor =        EVDEV_MINOR_BASE,
672         .name =         "evdev",
673         .id_table =     evdev_ids,
674 };
675
676 static int __init evdev_init(void)
677 {
678         input_register_handler(&evdev_handler);
679         return 0;
680 }
681
682 static void __exit evdev_exit(void)
683 {
684         input_unregister_handler(&evdev_handler);
685 }
686
687 module_init(evdev_init);
688 module_exit(evdev_exit);
689
690 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
691 MODULE_DESCRIPTION("Input driver event char devices");
692 MODULE_LICENSE("GPL");