summaryrefslogtreecommitdiffstats
path: root/drivers/input/input.c
blob: 83c77c990ddab8b8e6a6e17e4f360d3d2d0b40d1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
/*
 * The input core
 *
 * Copyright (c) 1999-2002 Vojtech Pavlik
 */

/*
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 */

#include <linux/init.h>
#include <linux/sched.h>
#include <linux/smp_lock.h>
#include <linux/input.h>
#include <linux/module.h>
#include <linux/random.h>
#include <linux/major.h>
#include <linux/proc_fs.h>
#include <linux/kobject_uevent.h>
#include <linux/interrupt.h>
#include <linux/poll.h>
#include <linux/device.h>
#include <linux/devfs_fs_kernel.h>

MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
MODULE_DESCRIPTION("Input core");
MODULE_LICENSE("GPL");

EXPORT_SYMBOL(input_register_device);
EXPORT_SYMBOL(input_unregister_device);
EXPORT_SYMBOL(input_register_handler);
EXPORT_SYMBOL(input_unregister_handler);
EXPORT_SYMBOL(input_grab_device);
EXPORT_SYMBOL(input_release_device);
EXPORT_SYMBOL(input_open_device);
EXPORT_SYMBOL(input_close_device);
EXPORT_SYMBOL(input_accept_process);
EXPORT_SYMBOL(input_flush_device);
EXPORT_SYMBOL(input_event);
EXPORT_SYMBOL(input_class);

#define INPUT_DEVICES	256

static LIST_HEAD(input_dev_list);
static LIST_HEAD(input_handler_list);

static struct input_handler *input_table[8];

#ifdef CONFIG_PROC_FS
static struct proc_dir_entry *proc_bus_input_dir;
static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
static int input_devices_state;
#endif

void input_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)
{
	struct input_handle *handle;

	if (type > EV_MAX || !test_bit(type, dev->evbit))
		return;

	add_input_randomness(type, code, value);

	switch (type) {

		case EV_SYN:
			switch (code) {
				case SYN_CONFIG:
					if (dev->event) dev->event(dev, type, code, value);
					break;

				case SYN_REPORT:
					if (dev->sync) return;
					dev->sync = 1;
					break;
			}
			break;

		case EV_KEY:

			if (code > KEY_MAX || !test_bit(code, dev->keybit) || !!test_bit(code, dev->key) == value)
				return;

			if (value == 2)
				break;

			change_bit(code, dev->key);

			if (test_bit(EV_REP, dev->evbit) && dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] && dev->timer.data && value) {
				dev->repeat_key = code;
				mod_timer(&dev->timer, jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
			}

			break;

		case EV_ABS:

			if (code > ABS_MAX || !test_bit(code, dev->absbit))
				return;

			if (dev->absfuzz[code]) {
				if ((value > dev->abs[code] - (dev->absfuzz[code] >> 1)) &&
				    (value < dev->abs[code] + (dev->absfuzz[code] >> 1)))
					return;

				if ((value > dev->abs[code] - dev->absfuzz[code]) &&
				    (value < dev->abs[code] + dev->absfuzz[code]))
					value = (dev->abs[code] * 3 + value) >> 2;

				if ((value > dev->abs[code] - (dev->absfuzz[code] << 1)) &&
				    (value < dev->abs[code] + (dev->absfuzz[code] << 1)))
					value = (dev->abs[code] + value) >> 1;
			}

			if (dev->abs[code] == value)
				return;

			dev->abs[code] = value;
			break;

		case EV_REL:

			if (code > REL_MAX || !test_bit(code, dev->relbit) || (value == 0))
				return;

			break;

		case EV_MSC:

			if (code > MSC_MAX || !test_bit(code, dev->mscbit))
				return;

			if (dev->event) dev->event(dev, type, code, value);

			break;

		case EV_LED:

			if (code > LED_MAX || !test_bit(code, dev->ledbit) || !!test_bit(code, dev->led) == value)
				return;

			change_bit(code, dev->led);
			if (dev->event) dev->event(dev, type, code, value);

			break;

		case EV_SND:

			if (code > SND_MAX || !test_bit(code, dev->sndbit))
				return;

			if (dev->event) dev->event(dev, type, code, value);

			break;

		case EV_REP:

			if (code > REP_MAX || value < 0 || dev->rep[code] == value) return;

			dev->rep[code] = value;
			if (dev->event) dev->event(dev, type, code, value);

			break;

		case EV_FF:
			if (dev->event) dev->event(dev, type, code, value);
			break;
	}

	if (type != EV_SYN)
		dev->sync = 0;

	if (dev->grab)
		dev->grab->handler->event(dev->grab, type, code, value);
	else
		list_for_each_entry(handle, &dev->h_list, d_node)
			if (handle->open)
				handle->handler->event(handle, type, code, value);
}

static void input_repeat_key(unsigned long data)
{
	struct input_dev *dev = (void *) data;

	if (!test_bit(dev->repeat_key, dev->key))
		return;

	input_event(dev, EV_KEY, dev->repeat_key, 2);
	input_sync(dev);

	if (dev->rep[REP_PERIOD])
		mod_timer(&dev->timer, jiffies + msecs_to_jiffies(dev->rep[REP_PERIOD]));
}

int input_accept_process(struct input_handle *handle, struct file *file)
{
	if (handle->dev->accept)
		return handle->dev->accept(handle->dev, file);

	return 0;
}

int input_grab_device(struct input_handle *handle)
{
	if (handle->dev->grab)
		return -EBUSY;

	handle->dev->grab = handle;
	return 0;
}

void input_release_device(struct input_handle *handle)
{
	if (handle->dev->grab == handle)
		handle->dev->grab = NULL;
}

int input_open_device(struct input_handle *handle)
{
	handle->open++;
	if (handle->dev->open)
		return handle->dev->open(handle->dev);
	return 0;
}

int input_flush_device(struct input_handle* handle, struct file* file)
{
	if (handle->dev->flush)
		return handle->dev->flush(handle->dev, file);

	return 0;
}

void input_close_device(struct input_handle *handle)
{
	input_release_device(handle);
	if (handle->dev->close)
		handle->dev->close(handle->dev);
	handle->open--;
}

static void input_link_handle(struct input_handle *handle)
{
	list_add_tail(&handle->d_node, &handle->dev->h_list);
	list_add_tail(&handle->h_node, &handle->handler->h_list);
}

#define MATCH_BIT(bit, max) \
		for (i = 0; i < NBITS(max); i++) \
			if ((id->bit[i] & dev->bit[i]) != id->bit[i]) \
				break; \
		if (i != NBITS(max)) \
			continue;

static struct input_device_id *input_match_device(struct input_device_id *id, struct input_dev *dev)
{
	int i;

	for (; id->flags || id->driver_info; id++) {

		if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
			if (id->id.bustype != dev->id.bustype)
				continue;

		if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
			if (id->id.vendor != dev->id.vendor)
				continue;

		if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
			if (id->id.product != dev->id.product)
				continue;

		if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
			if (id->id.version != dev->id.version)
				continue;

		MATCH_BIT(evbit,  EV_MAX);
		MATCH_BIT(keybit, KEY_MAX);
		MATCH_BIT(relbit, REL_MAX);
		MATCH_BIT(absbit, ABS_MAX);
		MATCH_BIT(mscbit, MSC_MAX);
		MATCH_BIT(ledbit, LED_MAX);
		MATCH_BIT(sndbit, SND_MAX);
		MATCH_BIT(ffbit,  FF_MAX);

		return id;
	}

	return NULL;
}

/*
 * Input hotplugging interface - loading event handlers based on
 * device bitfields.
 */

#ifdef CONFIG_HOTPLUG

/*
 * Input hotplugging invokes what /proc/sys/kernel/hotplug says
 * (normally /sbin/hotplug) when input devices get added or removed.
 *
 * This invokes a user mode policy agent, typically helping to load driver
 * or other modules, configure the device, and more.  Drivers can provide
 * a MODULE_DEVICE_TABLE to help with module loading subtasks.
 *
 */

#define SPRINTF_BIT_A(bit, name, max) \
	do { \
		envp[i++] = scratch; \
		scratch += sprintf(scratch, name); \
		for (j = NBITS(max) - 1; j >= 0; j--) \
			if (dev->bit[j]) break; \
		for (; j >= 0; j--) \
			scratch += sprintf(scratch, "%lx ", dev->bit[j]); \
		scratch++; \
	} while (0)

#define SPRINTF_BIT_A2(bit, name, max, ev) \
	do { \
		if (test_bit(ev, dev->evbit)) \
			SPRINTF_BIT_A(bit, name, max); \
	} while (0)

static void input_call_hotplug(char *verb, struct input_dev *dev)
{
	char *argv[3], **envp, *buf, *scratch;
	int i = 0, j, value;

	if (!hotplug_path[0]) {
		printk(KERN_ERR "input.c: calling hotplug without a hotplug agent defined\n");
		return;
	}
	if (in_interrupt()) {
		printk(KERN_ERR "input.c: calling hotplug from interrupt\n");
		return;
	}
	if (!current->fs->root) {
		printk(KERN_WARNING "input.c: calling hotplug without valid filesystem\n");
		return;
	}
	if (!(envp = (char **) kmalloc(20 * sizeof(char *), GFP_KERNEL))) {
		printk(KERN_ERR "input.c: not enough memory allocating hotplug environment\n");
		return;
	}
	if (!(buf = kmalloc(1024, GFP_KERNEL))) {
		kfree (envp);
		printk(KERN_ERR "input.c: not enough memory allocating hotplug environment\n");
		return;
	}

	argv[0] = hotplug_path;
	argv[1] = "input";
	argv[2] = NULL;

	envp[i++] = "HOME=/";
	envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";

	scratch = buf;

	envp[i++] = scratch;
	scratch += sprintf(scratch, "ACTION=%s", verb) + 1;

	envp[i++] = scratch;
	scratch += sprintf(scratch, "PRODUCT=%x/%x/%x/%x",
		dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version) + 1;

	if (dev->name) {
		envp[i++] = scratch;
		scratch += sprintf(scratch, "NAME=%s", dev->name) + 1;
	}

	if (dev->phys) {
		envp[i++] = scratch;
		scratch += sprintf(scratch, "PHYS=%s", dev->phys) + 1;
	}

	SPRINTF_BIT_A(evbit, "EV=", EV_MAX);
	SPRINTF_BIT_A2(keybit, "KEY=", KEY_MAX, EV_KEY);
	SPRINTF_BIT_A2(relbit, "REL=", REL_MAX, EV_REL);
	SPRINTF_BIT_A2(absbit, "ABS=", ABS_MAX, EV_ABS);
	SPRINTF_BIT_A2(mscbit, "MSC=", MSC_MAX, EV_MSC);
	SPRINTF_BIT_A2(ledbit, "LED=", LED_MAX, EV_LED);
	SPRINTF_BIT_A2(sndbit, "SND=", SND_MAX, EV_SND);
	SPRINTF_BIT_A2(ffbit,  "FF=",  FF_MAX, EV_FF);

	envp[i++] = NULL;

#ifdef INPUT_DEBUG
	printk(KERN_DEBUG "input.c: calling %s %s [%s %s %s %s %s]\n",
		argv[0], argv[1], envp[0], envp[1], envp[2], envp[3], envp[4]);
#endif

	value = call_usermodehelper(argv [0], argv, envp, 0);

	kfree(buf);
	kfree(envp);

#ifdef INPUT_DEBUG
	if (value != 0)
		printk(KERN_DEBUG "input.c: hotplug returned %d\n", value);
#endif
}

#endif

void input_register_device(struct input_dev *dev)
{
	struct input_handle *handle;
	struct input_handler *handler;
	struct input_device_id *id;

	set_bit(EV_SYN, dev->evbit);

	/*
	 * If delay and period are pre-set by the driver, then autorepeating
	 * is handled by the driver itself and we don't do it in input.c.
	 */

	init_timer(&dev->timer);
	if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD]) {
		dev->timer.data = (long) dev;
		dev->timer.function = input_repeat_key;
		dev->rep[REP_DELAY] = 250;
		dev->rep[REP_PERIOD] = 33;
	}

	INIT_LIST_HEAD(&dev->h_list);
	list_add_tail(&dev->node, &input_dev_list);

	list_for_each_entry(handler, &input_handler_list, node)
		if (!handler->blacklist || !input_match_device(handler->blacklist, dev))
			if ((id = input_match_device(handler->id_table, dev)))
				if ((handle = handler->connect(handler, dev, id)))
					input_link_handle(handle);

#ifdef CONFIG_HOTPLUG
	input_call_hotplug("add", dev);
#endif

#ifdef CONFIG_PROC_FS
	input_devices_state++;
	wake_up(&input_devices_poll_wait);
#endif
}

void input_unregister_device(struct input_dev *dev)
{
	struct list_head * node, * next;

	if (!dev) return;

	del_timer_sync(&dev->timer);

	list_for_each_safe(node, next, &dev->h_list) {
		struct input_handle * handle = to_handle(node);
		list_del_init(&handle->d_node);
		list_del_init(&handle->h_node);
		handle->handler->disconnect(handle);
	}

#ifdef CONFIG_HOTPLUG
	input_call_hotplug("remove", dev);
#endif

	list_del_init(&dev->node);

#ifdef CONFIG_PROC_FS
	input_devices_state++;
	wake_up(&input_devices_poll_wait);
#endif
}

void input_register_handler(struct input_handler *handler)
{
	struct input_dev *dev;
	struct input_handle *handle;
	struct input_device_id *id;

	if (!handler) return;

	INIT_LIST_HEAD(&handler->h_list);

	if (handler->fops != NULL)
		input_table[handler->minor >> 5] = handler;

	list_add_tail(&handler->node, &input_handler_list);

	list_for_each_entry(dev, &input_dev_list, node)
		if (!handler->blacklist || !input_match_device(handler->blacklist, dev))
			if ((id = input_match_device(handler->id_table, dev)))
				if ((handle = handler->connect(handler, dev, id)))
					input_link_handle(handle);

#ifdef CONFIG_PROC_FS
	input_devices_state++;
	wake_up(&input_devices_poll_wait);
#endif
}

void input_unregister_handler(struct input_handler *handler)
{
	struct list_head * node, * next;

	list_for_each_safe(node, next, &handler->h_list) {
		struct input_handle * handle = to_handle_h(node);
		list_del_init(&handle->h_node);
		list_del_init(&handle->d_node);
		handler->disconnect(handle);
	}

	list_del_init(&handler->node);

	if (handler->fops != NULL)
		input_table[handler->minor >> 5] = NULL;

#ifdef CONFIG_PROC_FS
	input_devices_state++;
	wake_up(&input_devices_poll_wait);
#endif
}

static int input_open_file(struct inode *inode, struct file *file)
{
	struct input_handler *handler = input_table[iminor(inode) >> 5];
	struct file_operations *old_fops, *new_fops = NULL;
	int err;

	/* No load-on-demand here? */
	if (!handler || !(new_fops = fops_get(handler->fops)))
		return -ENODEV;

	/*
	 * That's _really_ odd. Usually NULL ->open means "nothing special",
	 * not "no device". Oh, well...
	 */
	if (!new_fops->open) {
		fops_put(new_fops);
		return -ENODEV;
	}
	old_fops = file->f_op;
	file->f_op = new_fops;

	err = new_fops->open(inode, file);

	if (err) {
		fops_put(file->f_op);
		file->f_op = fops_get(old_fops);
	}
	fops_put(old_fops);
	return err;
}

static struct file_operations input_fops = {
	.owner = THIS_MODULE,
	.open = input_open_file,
};

#ifdef CONFIG_PROC_FS

#define SPRINTF_BIT_B(bit, name, max) \
	do { \
		len += sprintf(buf + len, "B: %s", name); \
		for (i = NBITS(max) - 1; i >= 0; i--) \
			if (dev->bit[i]) break; \
		for (; i >= 0; i--) \
			len += sprintf(buf + len, "%lx ", dev->bit[i]); \
		len += sprintf(buf + len, "\n"); \
	} while (0)

#define SPRINTF_BIT_B2(bit, name, max, ev) \
	do { \
		if (test_bit(ev, dev->evbit)) \
			SPRINTF_BIT_B(bit, name, max); \
	} while (0)


static unsigned int input_devices_poll(struct file *file, poll_table *wait)
{
	int state = input_devices_state;
	poll_wait(file, &input_devices_poll_wait, wait);
	if (state != input_devices_state)
		return POLLIN | POLLRDNORM;
	return 0;
}

static int input_devices_read(char *buf, char **start, off_t pos, int count, int *eof, void *data)
{
	struct input_dev *dev;
	struct input_handle *handle;

	off_t at = 0;
	int i, len, cnt = 0;

	list_for_each_entry(dev, &input_dev_list, node) {

		len = sprintf(buf, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
			dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);

		len += sprintf(buf + len, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
		len += sprintf(buf + len, "P: Phys=%s\n", dev->phys ? dev->phys : "");
		len += sprintf(buf + len, "H: Handlers=");

		list_for_each_entry(handle, &dev->h_list, d_node)
			len += sprintf(buf + len, "%s ", handle->name);

		len += sprintf(buf + len, "\n");

		SPRINTF_BIT_B(evbit, "EV=", EV_MAX);
		SPRINTF_BIT_B2(keybit, "KEY=", KEY_MAX, EV_KEY);
		SPRINTF_BIT_B2(relbit, "REL=", REL_MAX, EV_REL);
		SPRINTF_BIT_B2(absbit, "ABS=", ABS_MAX, EV_ABS);
		SPRINTF_BIT_B2(mscbit, "MSC=", MSC_MAX, EV_MSC);
		SPRINTF_BIT_B2(ledbit, "LED=", LED_MAX, EV_LED);
		SPRINTF_BIT_B2(sndbit, "SND=", SND_MAX, EV_SND);
		SPRINTF_BIT_B2(ffbit,  "FF=",  FF_MAX, EV_FF);

		len += sprintf(buf + len, "\n");

		at += len;

		if (at >= pos) {
			if (!*start) {
				*start = buf + (pos - (at - len));
				cnt = at - pos;
			} else  cnt += len;
			buf += len;
			if (cnt >= count)
				break;
		}
	}

	if (&dev->node == &input_dev_list)
		*eof = 1;

	return (count > cnt) ? cnt : count;
}

static int input_handlers_read(char *buf, char **start, off_t pos, int count, int *eof, void *data)
{
	struct input_handler *handler;

	off_t at = 0;
	int len = 0, cnt = 0;
	int i = 0;

	list_for_each_entry(handler, &input_handler_list, node) {

		if (handler->fops)
			len = sprintf(buf, "N: Number=%d Name=%s Minor=%d\n",
				i++, handler->name, handler->minor);
		else
			len = sprintf(buf, "N: Number=%d Name=%s\n",
				i++, handler->name);

		at += len;

		if (at >= pos) {
			if (!*start) {
				*start = buf + (pos - (at - len));
				cnt = at - pos;
			} else  cnt += len;
			buf += len;
			if (cnt >= count)
				break;
		}
	}
	if (&handler->node == &input_handler_list)
		*eof = 1;

	return (count > cnt) ? cnt : count;
}

static int __init input_proc_init(void)
{
	struct proc_dir_entry *entry;

	proc_bus_input_dir = proc_mkdir("input", proc_bus);
	if (proc_bus_input_dir == NULL)
		return -ENOMEM;
	proc_bus_input_dir->owner = THIS_MODULE;
	entry = create_proc_read_entry("devices", 0, proc_bus_input_dir, input_devices_read, NULL);
	if (entry == NULL) {
		remove_proc_entry("input", proc_bus);
		return -ENOMEM;
	}
	entry->owner = THIS_MODULE;
	entry->proc_fops->poll = input_devices_poll;
	entry = create_proc_read_entry("handlers", 0, proc_bus_input_dir, input_handlers_read, NULL);
	if (entry == NULL) {
		remove_proc_entry("devices", proc_bus_input_dir);
		remove_proc_entry("input", proc_bus);
		return -ENOMEM;
	}
	entry->owner = THIS_MODULE;
	return 0;
}
#else /* !CONFIG_PROC_FS */
static inline int input_proc_init(void) { return 0; }
#endif

struct class *input_class;

static int __init input_init(void)
{
	int retval = -ENOMEM;

	input_class = class_create(THIS_MODULE, "input");
	if (IS_ERR(input_class))
		return PTR_ERR(input_class);
	input_proc_init();
	retval = register_chrdev(INPUT_MAJOR, "input", &input_fops);
	if (retval) {
		printk(KERN_ERR "input: unable to register char major %d", INPUT_MAJOR);
		remove_proc_entry("devices", proc_bus_input_dir);
		remove_proc_entry("handlers", proc_bus_input_dir);
		remove_proc_entry("input", proc_bus);
		class_destroy(input_class);
		return retval;
	}

	retval = devfs_mk_dir("input");
	if (retval) {
		remove_proc_entry("devices", proc_bus_input_dir);
		remove_proc_entry("handlers", proc_bus_input_dir);
		remove_proc_entry("input", proc_bus);
		unregister_chrdev(INPUT_MAJOR, "input");
		class_destroy(input_class);
	}
	return retval;
}

static void __exit input_exit(void)
{
	remove_proc_entry("devices", proc_bus_input_dir);
	remove_proc_entry("handlers", proc_bus_input_dir);
	remove_proc_entry("input", proc_bus);

	devfs_remove("input");
	unregister_chrdev(INPUT_MAJOR, "input");
	class_destroy(input_class);
}

subsys_initcall(input_init);
module_exit(input_exit);
OpenPOWER on IntegriCloud