Input: do not corrupt system-wide procfs fops.
[linux-2.6.git] / drivers / input / input.c
1 /*
2  * The input core
3  *
4  * Copyright (c) 1999-2002 Vojtech Pavlik
5  */
6
7 /*
8  * This program is free software; you can redistribute it and/or modify it
9  * under the terms of the GNU General Public License version 2 as published by
10  * the Free Software Foundation.
11  */
12
13 #include <linux/init.h>
14 #include <linux/sched.h>
15 #include <linux/smp_lock.h>
16 #include <linux/input.h>
17 #include <linux/module.h>
18 #include <linux/random.h>
19 #include <linux/major.h>
20 #include <linux/proc_fs.h>
21 #include <linux/kobject_uevent.h>
22 #include <linux/interrupt.h>
23 #include <linux/poll.h>
24 #include <linux/device.h>
25 #include <linux/devfs_fs_kernel.h>
26
27 MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
28 MODULE_DESCRIPTION("Input core");
29 MODULE_LICENSE("GPL");
30
31 EXPORT_SYMBOL(input_register_device);
32 EXPORT_SYMBOL(input_unregister_device);
33 EXPORT_SYMBOL(input_register_handler);
34 EXPORT_SYMBOL(input_unregister_handler);
35 EXPORT_SYMBOL(input_grab_device);
36 EXPORT_SYMBOL(input_release_device);
37 EXPORT_SYMBOL(input_open_device);
38 EXPORT_SYMBOL(input_close_device);
39 EXPORT_SYMBOL(input_accept_process);
40 EXPORT_SYMBOL(input_flush_device);
41 EXPORT_SYMBOL(input_event);
42 EXPORT_SYMBOL(input_class);
43
44 #define INPUT_DEVICES   256
45
46 static LIST_HEAD(input_dev_list);
47 static LIST_HEAD(input_handler_list);
48
49 static struct input_handler *input_table[8];
50
51 #ifdef CONFIG_PROC_FS
52 static struct proc_dir_entry *proc_bus_input_dir;
53 static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
54 static int input_devices_state;
55 #endif
56
57 void input_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)
58 {
59         struct input_handle *handle;
60
61         if (type > EV_MAX || !test_bit(type, dev->evbit))
62                 return;
63
64         add_input_randomness(type, code, value);
65
66         switch (type) {
67
68                 case EV_SYN:
69                         switch (code) {
70                                 case SYN_CONFIG:
71                                         if (dev->event) dev->event(dev, type, code, value);
72                                         break;
73
74                                 case SYN_REPORT:
75                                         if (dev->sync) return;
76                                         dev->sync = 1;
77                                         break;
78                         }
79                         break;
80
81                 case EV_KEY:
82
83                         if (code > KEY_MAX || !test_bit(code, dev->keybit) || !!test_bit(code, dev->key) == value)
84                                 return;
85
86                         if (value == 2)
87                                 break;
88
89                         change_bit(code, dev->key);
90
91                         if (test_bit(EV_REP, dev->evbit) && dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] && dev->timer.data && value) {
92                                 dev->repeat_key = code;
93                                 mod_timer(&dev->timer, jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
94                         }
95
96                         break;
97
98                 case EV_ABS:
99
100                         if (code > ABS_MAX || !test_bit(code, dev->absbit))
101                                 return;
102
103                         if (dev->absfuzz[code]) {
104                                 if ((value > dev->abs[code] - (dev->absfuzz[code] >> 1)) &&
105                                     (value < dev->abs[code] + (dev->absfuzz[code] >> 1)))
106                                         return;
107
108                                 if ((value > dev->abs[code] - dev->absfuzz[code]) &&
109                                     (value < dev->abs[code] + dev->absfuzz[code]))
110                                         value = (dev->abs[code] * 3 + value) >> 2;
111
112                                 if ((value > dev->abs[code] - (dev->absfuzz[code] << 1)) &&
113                                     (value < dev->abs[code] + (dev->absfuzz[code] << 1)))
114                                         value = (dev->abs[code] + value) >> 1;
115                         }
116
117                         if (dev->abs[code] == value)
118                                 return;
119
120                         dev->abs[code] = value;
121                         break;
122
123                 case EV_REL:
124
125                         if (code > REL_MAX || !test_bit(code, dev->relbit) || (value == 0))
126                                 return;
127
128                         break;
129
130                 case EV_MSC:
131
132                         if (code > MSC_MAX || !test_bit(code, dev->mscbit))
133                                 return;
134
135                         if (dev->event) dev->event(dev, type, code, value);
136
137                         break;
138
139                 case EV_LED:
140
141                         if (code > LED_MAX || !test_bit(code, dev->ledbit) || !!test_bit(code, dev->led) == value)
142                                 return;
143
144                         change_bit(code, dev->led);
145                         if (dev->event) dev->event(dev, type, code, value);
146
147                         break;
148
149                 case EV_SND:
150
151                         if (code > SND_MAX || !test_bit(code, dev->sndbit))
152                                 return;
153
154                         if (dev->event) dev->event(dev, type, code, value);
155
156                         break;
157
158                 case EV_REP:
159
160                         if (code > REP_MAX || value < 0 || dev->rep[code] == value) return;
161
162                         dev->rep[code] = value;
163                         if (dev->event) dev->event(dev, type, code, value);
164
165                         break;
166
167                 case EV_FF:
168                         if (dev->event) dev->event(dev, type, code, value);
169                         break;
170         }
171
172         if (type != EV_SYN)
173                 dev->sync = 0;
174
175         if (dev->grab)
176                 dev->grab->handler->event(dev->grab, type, code, value);
177         else
178                 list_for_each_entry(handle, &dev->h_list, d_node)
179                         if (handle->open)
180                                 handle->handler->event(handle, type, code, value);
181 }
182
183 static void input_repeat_key(unsigned long data)
184 {
185         struct input_dev *dev = (void *) data;
186
187         if (!test_bit(dev->repeat_key, dev->key))
188                 return;
189
190         input_event(dev, EV_KEY, dev->repeat_key, 2);
191         input_sync(dev);
192
193         if (dev->rep[REP_PERIOD])
194                 mod_timer(&dev->timer, jiffies + msecs_to_jiffies(dev->rep[REP_PERIOD]));
195 }
196
197 int input_accept_process(struct input_handle *handle, struct file *file)
198 {
199         if (handle->dev->accept)
200                 return handle->dev->accept(handle->dev, file);
201
202         return 0;
203 }
204
205 int input_grab_device(struct input_handle *handle)
206 {
207         if (handle->dev->grab)
208                 return -EBUSY;
209
210         handle->dev->grab = handle;
211         return 0;
212 }
213
214 void input_release_device(struct input_handle *handle)
215 {
216         if (handle->dev->grab == handle)
217                 handle->dev->grab = NULL;
218 }
219
220 int input_open_device(struct input_handle *handle)
221 {
222         struct input_dev *dev = handle->dev;
223         int err;
224
225         err = down_interruptible(&dev->sem);
226         if (err)
227                 return err;
228
229         handle->open++;
230
231         if (!dev->users++ && dev->open)
232                 err = dev->open(dev);
233
234         if (err)
235                 handle->open--;
236
237         up(&dev->sem);
238
239         return err;
240 }
241
242 int input_flush_device(struct input_handle* handle, struct file* file)
243 {
244         if (handle->dev->flush)
245                 return handle->dev->flush(handle->dev, file);
246
247         return 0;
248 }
249
250 void input_close_device(struct input_handle *handle)
251 {
252         struct input_dev *dev = handle->dev;
253
254         input_release_device(handle);
255
256         down(&dev->sem);
257
258         if (!--dev->users && dev->close)
259                 dev->close(dev);
260         handle->open--;
261
262         up(&dev->sem);
263 }
264
265 static void input_link_handle(struct input_handle *handle)
266 {
267         list_add_tail(&handle->d_node, &handle->dev->h_list);
268         list_add_tail(&handle->h_node, &handle->handler->h_list);
269 }
270
271 #define MATCH_BIT(bit, max) \
272                 for (i = 0; i < NBITS(max); i++) \
273                         if ((id->bit[i] & dev->bit[i]) != id->bit[i]) \
274                                 break; \
275                 if (i != NBITS(max)) \
276                         continue;
277
278 static struct input_device_id *input_match_device(struct input_device_id *id, struct input_dev *dev)
279 {
280         int i;
281
282         for (; id->flags || id->driver_info; id++) {
283
284                 if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
285                         if (id->id.bustype != dev->id.bustype)
286                                 continue;
287
288                 if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
289                         if (id->id.vendor != dev->id.vendor)
290                                 continue;
291
292                 if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
293                         if (id->id.product != dev->id.product)
294                                 continue;
295
296                 if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
297                         if (id->id.version != dev->id.version)
298                                 continue;
299
300                 MATCH_BIT(evbit,  EV_MAX);
301                 MATCH_BIT(keybit, KEY_MAX);
302                 MATCH_BIT(relbit, REL_MAX);
303                 MATCH_BIT(absbit, ABS_MAX);
304                 MATCH_BIT(mscbit, MSC_MAX);
305                 MATCH_BIT(ledbit, LED_MAX);
306                 MATCH_BIT(sndbit, SND_MAX);
307                 MATCH_BIT(ffbit,  FF_MAX);
308
309                 return id;
310         }
311
312         return NULL;
313 }
314
315 /*
316  * Input hotplugging interface - loading event handlers based on
317  * device bitfields.
318  */
319
320 #ifdef CONFIG_HOTPLUG
321
322 /*
323  * Input hotplugging invokes what /proc/sys/kernel/hotplug says
324  * (normally /sbin/hotplug) when input devices get added or removed.
325  *
326  * This invokes a user mode policy agent, typically helping to load driver
327  * or other modules, configure the device, and more.  Drivers can provide
328  * a MODULE_DEVICE_TABLE to help with module loading subtasks.
329  *
330  */
331
332 #define SPRINTF_BIT_A(bit, name, max) \
333         do { \
334                 envp[i++] = scratch; \
335                 scratch += sprintf(scratch, name); \
336                 for (j = NBITS(max) - 1; j >= 0; j--) \
337                         if (dev->bit[j]) break; \
338                 for (; j >= 0; j--) \
339                         scratch += sprintf(scratch, "%lx ", dev->bit[j]); \
340                 scratch++; \
341         } while (0)
342
343 #define SPRINTF_BIT_A2(bit, name, max, ev) \
344         do { \
345                 if (test_bit(ev, dev->evbit)) \
346                         SPRINTF_BIT_A(bit, name, max); \
347         } while (0)
348
349 static void input_call_hotplug(char *verb, struct input_dev *dev)
350 {
351         char *argv[3], **envp, *buf, *scratch;
352         int i = 0, j, value;
353
354         if (!hotplug_path[0]) {
355                 printk(KERN_ERR "input.c: calling hotplug without a hotplug agent defined\n");
356                 return;
357         }
358         if (in_interrupt()) {
359                 printk(KERN_ERR "input.c: calling hotplug from interrupt\n");
360                 return;
361         }
362         if (!current->fs->root) {
363                 printk(KERN_WARNING "input.c: calling hotplug without valid filesystem\n");
364                 return;
365         }
366         if (!(envp = (char **) kmalloc(20 * sizeof(char *), GFP_KERNEL))) {
367                 printk(KERN_ERR "input.c: not enough memory allocating hotplug environment\n");
368                 return;
369         }
370         if (!(buf = kmalloc(1024, GFP_KERNEL))) {
371                 kfree (envp);
372                 printk(KERN_ERR "input.c: not enough memory allocating hotplug environment\n");
373                 return;
374         }
375
376         argv[0] = hotplug_path;
377         argv[1] = "input";
378         argv[2] = NULL;
379
380         envp[i++] = "HOME=/";
381         envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
382
383         scratch = buf;
384
385         envp[i++] = scratch;
386         scratch += sprintf(scratch, "ACTION=%s", verb) + 1;
387
388         envp[i++] = scratch;
389         scratch += sprintf(scratch, "PRODUCT=%x/%x/%x/%x",
390                 dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version) + 1;
391
392         if (dev->name) {
393                 envp[i++] = scratch;
394                 scratch += sprintf(scratch, "NAME=%s", dev->name) + 1;
395         }
396
397         if (dev->phys) {
398                 envp[i++] = scratch;
399                 scratch += sprintf(scratch, "PHYS=%s", dev->phys) + 1;
400         }
401
402         SPRINTF_BIT_A(evbit, "EV=", EV_MAX);
403         SPRINTF_BIT_A2(keybit, "KEY=", KEY_MAX, EV_KEY);
404         SPRINTF_BIT_A2(relbit, "REL=", REL_MAX, EV_REL);
405         SPRINTF_BIT_A2(absbit, "ABS=", ABS_MAX, EV_ABS);
406         SPRINTF_BIT_A2(mscbit, "MSC=", MSC_MAX, EV_MSC);
407         SPRINTF_BIT_A2(ledbit, "LED=", LED_MAX, EV_LED);
408         SPRINTF_BIT_A2(sndbit, "SND=", SND_MAX, EV_SND);
409         SPRINTF_BIT_A2(ffbit,  "FF=",  FF_MAX, EV_FF);
410
411         envp[i++] = NULL;
412
413 #ifdef INPUT_DEBUG
414         printk(KERN_DEBUG "input.c: calling %s %s [%s %s %s %s %s]\n",
415                 argv[0], argv[1], envp[0], envp[1], envp[2], envp[3], envp[4]);
416 #endif
417
418         value = call_usermodehelper(argv [0], argv, envp, 0);
419
420         kfree(buf);
421         kfree(envp);
422
423 #ifdef INPUT_DEBUG
424         if (value != 0)
425                 printk(KERN_DEBUG "input.c: hotplug returned %d\n", value);
426 #endif
427 }
428
429 #endif
430
431 void input_register_device(struct input_dev *dev)
432 {
433         struct input_handle *handle;
434         struct input_handler *handler;
435         struct input_device_id *id;
436
437         set_bit(EV_SYN, dev->evbit);
438
439         init_MUTEX(&dev->sem);
440
441         /*
442          * If delay and period are pre-set by the driver, then autorepeating
443          * is handled by the driver itself and we don't do it in input.c.
444          */
445
446         init_timer(&dev->timer);
447         if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD]) {
448                 dev->timer.data = (long) dev;
449                 dev->timer.function = input_repeat_key;
450                 dev->rep[REP_DELAY] = 250;
451                 dev->rep[REP_PERIOD] = 33;
452         }
453
454         INIT_LIST_HEAD(&dev->h_list);
455         list_add_tail(&dev->node, &input_dev_list);
456
457         list_for_each_entry(handler, &input_handler_list, node)
458                 if (!handler->blacklist || !input_match_device(handler->blacklist, dev))
459                         if ((id = input_match_device(handler->id_table, dev)))
460                                 if ((handle = handler->connect(handler, dev, id)))
461                                         input_link_handle(handle);
462
463 #ifdef CONFIG_HOTPLUG
464         input_call_hotplug("add", dev);
465 #endif
466
467 #ifdef CONFIG_PROC_FS
468         input_devices_state++;
469         wake_up(&input_devices_poll_wait);
470 #endif
471 }
472
473 void input_unregister_device(struct input_dev *dev)
474 {
475         struct list_head * node, * next;
476
477         if (!dev) return;
478
479         del_timer_sync(&dev->timer);
480
481         list_for_each_safe(node, next, &dev->h_list) {
482                 struct input_handle * handle = to_handle(node);
483                 list_del_init(&handle->d_node);
484                 list_del_init(&handle->h_node);
485                 handle->handler->disconnect(handle);
486         }
487
488 #ifdef CONFIG_HOTPLUG
489         input_call_hotplug("remove", dev);
490 #endif
491
492         list_del_init(&dev->node);
493
494 #ifdef CONFIG_PROC_FS
495         input_devices_state++;
496         wake_up(&input_devices_poll_wait);
497 #endif
498 }
499
500 void input_register_handler(struct input_handler *handler)
501 {
502         struct input_dev *dev;
503         struct input_handle *handle;
504         struct input_device_id *id;
505
506         if (!handler) return;
507
508         INIT_LIST_HEAD(&handler->h_list);
509
510         if (handler->fops != NULL)
511                 input_table[handler->minor >> 5] = handler;
512
513         list_add_tail(&handler->node, &input_handler_list);
514
515         list_for_each_entry(dev, &input_dev_list, node)
516                 if (!handler->blacklist || !input_match_device(handler->blacklist, dev))
517                         if ((id = input_match_device(handler->id_table, dev)))
518                                 if ((handle = handler->connect(handler, dev, id)))
519                                         input_link_handle(handle);
520
521 #ifdef CONFIG_PROC_FS
522         input_devices_state++;
523         wake_up(&input_devices_poll_wait);
524 #endif
525 }
526
527 void input_unregister_handler(struct input_handler *handler)
528 {
529         struct list_head * node, * next;
530
531         list_for_each_safe(node, next, &handler->h_list) {
532                 struct input_handle * handle = to_handle_h(node);
533                 list_del_init(&handle->h_node);
534                 list_del_init(&handle->d_node);
535                 handler->disconnect(handle);
536         }
537
538         list_del_init(&handler->node);
539
540         if (handler->fops != NULL)
541                 input_table[handler->minor >> 5] = NULL;
542
543 #ifdef CONFIG_PROC_FS
544         input_devices_state++;
545         wake_up(&input_devices_poll_wait);
546 #endif
547 }
548
549 static int input_open_file(struct inode *inode, struct file *file)
550 {
551         struct input_handler *handler = input_table[iminor(inode) >> 5];
552         struct file_operations *old_fops, *new_fops = NULL;
553         int err;
554
555         /* No load-on-demand here? */
556         if (!handler || !(new_fops = fops_get(handler->fops)))
557                 return -ENODEV;
558
559         /*
560          * That's _really_ odd. Usually NULL ->open means "nothing special",
561          * not "no device". Oh, well...
562          */
563         if (!new_fops->open) {
564                 fops_put(new_fops);
565                 return -ENODEV;
566         }
567         old_fops = file->f_op;
568         file->f_op = new_fops;
569
570         err = new_fops->open(inode, file);
571
572         if (err) {
573                 fops_put(file->f_op);
574                 file->f_op = fops_get(old_fops);
575         }
576         fops_put(old_fops);
577         return err;
578 }
579
580 static struct file_operations input_fops = {
581         .owner = THIS_MODULE,
582         .open = input_open_file,
583 };
584
585 #ifdef CONFIG_PROC_FS
586
587 #define SPRINTF_BIT_B(bit, name, max) \
588         do { \
589                 len += sprintf(buf + len, "B: %s", name); \
590                 for (i = NBITS(max) - 1; i >= 0; i--) \
591                         if (dev->bit[i]) break; \
592                 for (; i >= 0; i--) \
593                         len += sprintf(buf + len, "%lx ", dev->bit[i]); \
594                 len += sprintf(buf + len, "\n"); \
595         } while (0)
596
597 #define SPRINTF_BIT_B2(bit, name, max, ev) \
598         do { \
599                 if (test_bit(ev, dev->evbit)) \
600                         SPRINTF_BIT_B(bit, name, max); \
601         } while (0)
602
603
604 static unsigned int input_devices_poll(struct file *file, poll_table *wait)
605 {
606         int state = input_devices_state;
607         poll_wait(file, &input_devices_poll_wait, wait);
608         if (state != input_devices_state)
609                 return POLLIN | POLLRDNORM;
610         return 0;
611 }
612
613 static int input_devices_read(char *buf, char **start, off_t pos, int count, int *eof, void *data)
614 {
615         struct input_dev *dev;
616         struct input_handle *handle;
617
618         off_t at = 0;
619         int i, len, cnt = 0;
620
621         list_for_each_entry(dev, &input_dev_list, node) {
622
623                 len = sprintf(buf, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
624                         dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
625
626                 len += sprintf(buf + len, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
627                 len += sprintf(buf + len, "P: Phys=%s\n", dev->phys ? dev->phys : "");
628                 len += sprintf(buf + len, "H: Handlers=");
629
630                 list_for_each_entry(handle, &dev->h_list, d_node)
631                         len += sprintf(buf + len, "%s ", handle->name);
632
633                 len += sprintf(buf + len, "\n");
634
635                 SPRINTF_BIT_B(evbit, "EV=", EV_MAX);
636                 SPRINTF_BIT_B2(keybit, "KEY=", KEY_MAX, EV_KEY);
637                 SPRINTF_BIT_B2(relbit, "REL=", REL_MAX, EV_REL);
638                 SPRINTF_BIT_B2(absbit, "ABS=", ABS_MAX, EV_ABS);
639                 SPRINTF_BIT_B2(mscbit, "MSC=", MSC_MAX, EV_MSC);
640                 SPRINTF_BIT_B2(ledbit, "LED=", LED_MAX, EV_LED);
641                 SPRINTF_BIT_B2(sndbit, "SND=", SND_MAX, EV_SND);
642                 SPRINTF_BIT_B2(ffbit,  "FF=",  FF_MAX, EV_FF);
643
644                 len += sprintf(buf + len, "\n");
645
646                 at += len;
647
648                 if (at >= pos) {
649                         if (!*start) {
650                                 *start = buf + (pos - (at - len));
651                                 cnt = at - pos;
652                         } else  cnt += len;
653                         buf += len;
654                         if (cnt >= count)
655                                 break;
656                 }
657         }
658
659         if (&dev->node == &input_dev_list)
660                 *eof = 1;
661
662         return (count > cnt) ? cnt : count;
663 }
664
665 static int input_handlers_read(char *buf, char **start, off_t pos, int count, int *eof, void *data)
666 {
667         struct input_handler *handler;
668
669         off_t at = 0;
670         int len = 0, cnt = 0;
671         int i = 0;
672
673         list_for_each_entry(handler, &input_handler_list, node) {
674
675                 if (handler->fops)
676                         len = sprintf(buf, "N: Number=%d Name=%s Minor=%d\n",
677                                 i++, handler->name, handler->minor);
678                 else
679                         len = sprintf(buf, "N: Number=%d Name=%s\n",
680                                 i++, handler->name);
681
682                 at += len;
683
684                 if (at >= pos) {
685                         if (!*start) {
686                                 *start = buf + (pos - (at - len));
687                                 cnt = at - pos;
688                         } else  cnt += len;
689                         buf += len;
690                         if (cnt >= count)
691                                 break;
692                 }
693         }
694         if (&handler->node == &input_handler_list)
695                 *eof = 1;
696
697         return (count > cnt) ? cnt : count;
698 }
699
700 static struct file_operations input_fileops;
701
702 static int __init input_proc_init(void)
703 {
704         struct proc_dir_entry *entry;
705
706         proc_bus_input_dir = proc_mkdir("input", proc_bus);
707         if (proc_bus_input_dir == NULL)
708                 return -ENOMEM;
709         proc_bus_input_dir->owner = THIS_MODULE;
710         entry = create_proc_read_entry("devices", 0, proc_bus_input_dir, input_devices_read, NULL);
711         if (entry == NULL) {
712                 remove_proc_entry("input", proc_bus);
713                 return -ENOMEM;
714         }
715         entry->owner = THIS_MODULE;
716         input_fileops = *entry->proc_fops;
717         entry->proc_fops = &input_fileops;
718         entry->proc_fops->poll = input_devices_poll;
719         entry = create_proc_read_entry("handlers", 0, proc_bus_input_dir, input_handlers_read, NULL);
720         if (entry == NULL) {
721                 remove_proc_entry("devices", proc_bus_input_dir);
722                 remove_proc_entry("input", proc_bus);
723                 return -ENOMEM;
724         }
725         entry->owner = THIS_MODULE;
726         return 0;
727 }
728 #else /* !CONFIG_PROC_FS */
729 static inline int input_proc_init(void) { return 0; }
730 #endif
731
732 struct class_simple *input_class;
733
734 static int __init input_init(void)
735 {
736         int retval = -ENOMEM;
737
738         input_class = class_simple_create(THIS_MODULE, "input");
739         if (IS_ERR(input_class))
740                 return PTR_ERR(input_class);
741         input_proc_init();
742         retval = register_chrdev(INPUT_MAJOR, "input", &input_fops);
743         if (retval) {
744                 printk(KERN_ERR "input: unable to register char major %d", INPUT_MAJOR);
745                 remove_proc_entry("devices", proc_bus_input_dir);
746                 remove_proc_entry("handlers", proc_bus_input_dir);
747                 remove_proc_entry("input", proc_bus);
748                 class_simple_destroy(input_class);
749                 return retval;
750         }
751
752         retval = devfs_mk_dir("input");
753         if (retval) {
754                 remove_proc_entry("devices", proc_bus_input_dir);
755                 remove_proc_entry("handlers", proc_bus_input_dir);
756                 remove_proc_entry("input", proc_bus);
757                 unregister_chrdev(INPUT_MAJOR, "input");
758                 class_simple_destroy(input_class);
759         }
760         return retval;
761 }
762
763 static void __exit input_exit(void)
764 {
765         remove_proc_entry("devices", proc_bus_input_dir);
766         remove_proc_entry("handlers", proc_bus_input_dir);
767         remove_proc_entry("input", proc_bus);
768
769         devfs_remove("input");
770         unregister_chrdev(INPUT_MAJOR, "input");
771         class_simple_destroy(input_class);
772 }
773
774 subsys_initcall(input_init);
775 module_exit(input_exit);