xref: /linux/drivers/input/input.c (revision eb2bce7f5e7ac1ca6da434461217fadf3c688d2c)
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/smp_lock.h>
15 #include <linux/input.h>
16 #include <linux/module.h>
17 #include <linux/random.h>
18 #include <linux/major.h>
19 #include <linux/proc_fs.h>
20 #include <linux/seq_file.h>
21 #include <linux/interrupt.h>
22 #include <linux/poll.h>
23 #include <linux/device.h>
24 #include <linux/mutex.h>
25 
26 MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
27 MODULE_DESCRIPTION("Input core");
28 MODULE_LICENSE("GPL");
29 
30 #define INPUT_DEVICES	256
31 
32 static LIST_HEAD(input_dev_list);
33 static LIST_HEAD(input_handler_list);
34 
35 static struct input_handler *input_table[8];
36 
37 /**
38  * input_event() - report new input event
39  * @dev: device that generated the event
40  * @type: type of the event
41  * @code: event code
42  * @value: value of the event
43  *
44  * This function should be used by drivers implementing various input devices
45  * See also input_inject_event()
46  */
47 void input_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)
48 {
49 	struct input_handle *handle;
50 
51 	if (type > EV_MAX || !test_bit(type, dev->evbit))
52 		return;
53 
54 	add_input_randomness(type, code, value);
55 
56 	switch (type) {
57 
58 		case EV_SYN:
59 			switch (code) {
60 				case SYN_CONFIG:
61 					if (dev->event)
62 						dev->event(dev, type, code, value);
63 					break;
64 
65 				case SYN_REPORT:
66 					if (dev->sync)
67 						return;
68 					dev->sync = 1;
69 					break;
70 			}
71 			break;
72 
73 		case EV_KEY:
74 
75 			if (code > KEY_MAX || !test_bit(code, dev->keybit) || !!test_bit(code, dev->key) == value)
76 				return;
77 
78 			if (value == 2)
79 				break;
80 
81 			change_bit(code, dev->key);
82 
83 			if (test_bit(EV_REP, dev->evbit) && dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] && dev->timer.data && value) {
84 				dev->repeat_key = code;
85 				mod_timer(&dev->timer, jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
86 			}
87 
88 			break;
89 
90 		case EV_SW:
91 
92 			if (code > SW_MAX || !test_bit(code, dev->swbit) || !!test_bit(code, dev->sw) == value)
93 				return;
94 
95 			change_bit(code, dev->sw);
96 
97 			break;
98 
99 		case EV_ABS:
100 
101 			if (code > ABS_MAX || !test_bit(code, dev->absbit))
102 				return;
103 
104 			if (dev->absfuzz[code]) {
105 				if ((value > dev->abs[code] - (dev->absfuzz[code] >> 1)) &&
106 				    (value < dev->abs[code] + (dev->absfuzz[code] >> 1)))
107 					return;
108 
109 				if ((value > dev->abs[code] - dev->absfuzz[code]) &&
110 				    (value < dev->abs[code] + dev->absfuzz[code]))
111 					value = (dev->abs[code] * 3 + value) >> 2;
112 
113 				if ((value > dev->abs[code] - (dev->absfuzz[code] << 1)) &&
114 				    (value < dev->abs[code] + (dev->absfuzz[code] << 1)))
115 					value = (dev->abs[code] + value) >> 1;
116 			}
117 
118 			if (dev->abs[code] == value)
119 				return;
120 
121 			dev->abs[code] = value;
122 			break;
123 
124 		case EV_REL:
125 
126 			if (code > REL_MAX || !test_bit(code, dev->relbit) || (value == 0))
127 				return;
128 
129 			break;
130 
131 		case EV_MSC:
132 
133 			if (code > MSC_MAX || !test_bit(code, dev->mscbit))
134 				return;
135 
136 			if (dev->event)
137 				dev->event(dev, type, code, value);
138 
139 			break;
140 
141 		case EV_LED:
142 
143 			if (code > LED_MAX || !test_bit(code, dev->ledbit) || !!test_bit(code, dev->led) == value)
144 				return;
145 
146 			change_bit(code, dev->led);
147 
148 			if (dev->event)
149 				dev->event(dev, type, code, value);
150 
151 			break;
152 
153 		case EV_SND:
154 
155 			if (code > SND_MAX || !test_bit(code, dev->sndbit))
156 				return;
157 
158 			if (!!test_bit(code, dev->snd) != !!value)
159 				change_bit(code, dev->snd);
160 
161 			if (dev->event)
162 				dev->event(dev, type, code, value);
163 
164 			break;
165 
166 		case EV_REP:
167 
168 			if (code > REP_MAX || value < 0 || dev->rep[code] == value)
169 				return;
170 
171 			dev->rep[code] = value;
172 			if (dev->event)
173 				dev->event(dev, type, code, value);
174 
175 			break;
176 
177 		case EV_FF:
178 
179 			if (value < 0)
180 				return;
181 
182 			if (dev->event)
183 				dev->event(dev, type, code, value);
184 			break;
185 	}
186 
187 	if (type != EV_SYN)
188 		dev->sync = 0;
189 
190 	if (dev->grab)
191 		dev->grab->handler->event(dev->grab, type, code, value);
192 	else
193 		list_for_each_entry(handle, &dev->h_list, d_node)
194 			if (handle->open)
195 				handle->handler->event(handle, type, code, value);
196 }
197 EXPORT_SYMBOL(input_event);
198 
199 /**
200  * input_inject_event() - send input event from input handler
201  * @handle: input handle to send event through
202  * @type: type of the event
203  * @code: event code
204  * @value: value of the event
205  *
206  * Similar to input_event() but will ignore event if device is "grabbed" and handle
207  * injecting event is not the one that owns the device.
208  */
209 void input_inject_event(struct input_handle *handle, unsigned int type, unsigned int code, int value)
210 {
211 	if (!handle->dev->grab || handle->dev->grab == handle)
212 		input_event(handle->dev, type, code, value);
213 }
214 EXPORT_SYMBOL(input_inject_event);
215 
216 static void input_repeat_key(unsigned long data)
217 {
218 	struct input_dev *dev = (void *) data;
219 
220 	if (!test_bit(dev->repeat_key, dev->key))
221 		return;
222 
223 	input_event(dev, EV_KEY, dev->repeat_key, 2);
224 	input_sync(dev);
225 
226 	if (dev->rep[REP_PERIOD])
227 		mod_timer(&dev->timer, jiffies + msecs_to_jiffies(dev->rep[REP_PERIOD]));
228 }
229 
230 int input_grab_device(struct input_handle *handle)
231 {
232 	if (handle->dev->grab)
233 		return -EBUSY;
234 
235 	handle->dev->grab = handle;
236 	return 0;
237 }
238 EXPORT_SYMBOL(input_grab_device);
239 
240 void input_release_device(struct input_handle *handle)
241 {
242 	struct input_dev *dev = handle->dev;
243 
244 	if (dev->grab == handle) {
245 		dev->grab = NULL;
246 
247 		list_for_each_entry(handle, &dev->h_list, d_node)
248 			if (handle->handler->start)
249 				handle->handler->start(handle);
250 	}
251 }
252 EXPORT_SYMBOL(input_release_device);
253 
254 int input_open_device(struct input_handle *handle)
255 {
256 	struct input_dev *dev = handle->dev;
257 	int err;
258 
259 	err = mutex_lock_interruptible(&dev->mutex);
260 	if (err)
261 		return err;
262 
263 	handle->open++;
264 
265 	if (!dev->users++ && dev->open)
266 		err = dev->open(dev);
267 
268 	if (err)
269 		handle->open--;
270 
271 	mutex_unlock(&dev->mutex);
272 
273 	return err;
274 }
275 EXPORT_SYMBOL(input_open_device);
276 
277 int input_flush_device(struct input_handle* handle, struct file* file)
278 {
279 	if (handle->dev->flush)
280 		return handle->dev->flush(handle->dev, file);
281 
282 	return 0;
283 }
284 EXPORT_SYMBOL(input_flush_device);
285 
286 void input_close_device(struct input_handle *handle)
287 {
288 	struct input_dev *dev = handle->dev;
289 
290 	input_release_device(handle);
291 
292 	mutex_lock(&dev->mutex);
293 
294 	if (!--dev->users && dev->close)
295 		dev->close(dev);
296 	handle->open--;
297 
298 	mutex_unlock(&dev->mutex);
299 }
300 EXPORT_SYMBOL(input_close_device);
301 
302 static int input_fetch_keycode(struct input_dev *dev, int scancode)
303 {
304 	switch (dev->keycodesize) {
305 		case 1:
306 			return ((u8 *)dev->keycode)[scancode];
307 
308 		case 2:
309 			return ((u16 *)dev->keycode)[scancode];
310 
311 		default:
312 			return ((u32 *)dev->keycode)[scancode];
313 	}
314 }
315 
316 static int input_default_getkeycode(struct input_dev *dev,
317 				    int scancode, int *keycode)
318 {
319 	if (!dev->keycodesize)
320 		return -EINVAL;
321 
322 	if (scancode < 0 || scancode >= dev->keycodemax)
323 		return -EINVAL;
324 
325 	*keycode = input_fetch_keycode(dev, scancode);
326 
327 	return 0;
328 }
329 
330 static int input_default_setkeycode(struct input_dev *dev,
331 				    int scancode, int keycode)
332 {
333 	int old_keycode;
334 	int i;
335 
336 	if (scancode < 0 || scancode >= dev->keycodemax)
337 		return -EINVAL;
338 
339 	if (keycode < 0 || keycode > KEY_MAX)
340 		return -EINVAL;
341 
342 	if (!dev->keycodesize)
343 		return -EINVAL;
344 
345 	if (dev->keycodesize < sizeof(keycode) && (keycode >> (dev->keycodesize * 8)))
346 		return -EINVAL;
347 
348 	switch (dev->keycodesize) {
349 		case 1: {
350 			u8 *k = (u8 *)dev->keycode;
351 			old_keycode = k[scancode];
352 			k[scancode] = keycode;
353 			break;
354 		}
355 		case 2: {
356 			u16 *k = (u16 *)dev->keycode;
357 			old_keycode = k[scancode];
358 			k[scancode] = keycode;
359 			break;
360 		}
361 		default: {
362 			u32 *k = (u32 *)dev->keycode;
363 			old_keycode = k[scancode];
364 			k[scancode] = keycode;
365 			break;
366 		}
367 	}
368 
369 	clear_bit(old_keycode, dev->keybit);
370 	set_bit(keycode, dev->keybit);
371 
372 	for (i = 0; i < dev->keycodemax; i++) {
373 		if (input_fetch_keycode(dev, i) == old_keycode) {
374 			set_bit(old_keycode, dev->keybit);
375 			break; /* Setting the bit twice is useless, so break */
376 		}
377 	}
378 
379 	return 0;
380 }
381 
382 
383 #define MATCH_BIT(bit, max) \
384 		for (i = 0; i < NBITS(max); i++) \
385 			if ((id->bit[i] & dev->bit[i]) != id->bit[i]) \
386 				break; \
387 		if (i != NBITS(max)) \
388 			continue;
389 
390 static const struct input_device_id *input_match_device(const struct input_device_id *id,
391 							struct input_dev *dev)
392 {
393 	int i;
394 
395 	for (; id->flags || id->driver_info; id++) {
396 
397 		if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
398 			if (id->bustype != dev->id.bustype)
399 				continue;
400 
401 		if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
402 			if (id->vendor != dev->id.vendor)
403 				continue;
404 
405 		if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
406 			if (id->product != dev->id.product)
407 				continue;
408 
409 		if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
410 			if (id->version != dev->id.version)
411 				continue;
412 
413 		MATCH_BIT(evbit,  EV_MAX);
414 		MATCH_BIT(keybit, KEY_MAX);
415 		MATCH_BIT(relbit, REL_MAX);
416 		MATCH_BIT(absbit, ABS_MAX);
417 		MATCH_BIT(mscbit, MSC_MAX);
418 		MATCH_BIT(ledbit, LED_MAX);
419 		MATCH_BIT(sndbit, SND_MAX);
420 		MATCH_BIT(ffbit,  FF_MAX);
421 		MATCH_BIT(swbit,  SW_MAX);
422 
423 		return id;
424 	}
425 
426 	return NULL;
427 }
428 
429 static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
430 {
431 	const struct input_device_id *id;
432 	int error;
433 
434 	if (handler->blacklist && input_match_device(handler->blacklist, dev))
435 		return -ENODEV;
436 
437 	id = input_match_device(handler->id_table, dev);
438 	if (!id)
439 		return -ENODEV;
440 
441 	error = handler->connect(handler, dev, id);
442 	if (error && error != -ENODEV)
443 		printk(KERN_ERR
444 			"input: failed to attach handler %s to device %s, "
445 			"error: %d\n",
446 			handler->name, kobject_name(&dev->cdev.kobj), error);
447 
448 	return error;
449 }
450 
451 
452 #ifdef CONFIG_PROC_FS
453 
454 static struct proc_dir_entry *proc_bus_input_dir;
455 static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
456 static int input_devices_state;
457 
458 static inline void input_wakeup_procfs_readers(void)
459 {
460 	input_devices_state++;
461 	wake_up(&input_devices_poll_wait);
462 }
463 
464 static unsigned int input_proc_devices_poll(struct file *file, poll_table *wait)
465 {
466 	int state = input_devices_state;
467 
468 	poll_wait(file, &input_devices_poll_wait, wait);
469 	if (state != input_devices_state)
470 		return POLLIN | POLLRDNORM;
471 
472 	return 0;
473 }
474 
475 static struct list_head *list_get_nth_element(struct list_head *list, loff_t *pos)
476 {
477 	struct list_head *node;
478 	loff_t i = 0;
479 
480 	list_for_each(node, list)
481 		if (i++ == *pos)
482 			return node;
483 
484 	return NULL;
485 }
486 
487 static struct list_head *list_get_next_element(struct list_head *list, struct list_head *element, loff_t *pos)
488 {
489 	if (element->next == list)
490 		return NULL;
491 
492 	++(*pos);
493 	return element->next;
494 }
495 
496 static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
497 {
498 	/* acquire lock here ... Yes, we do need locking, I knowi, I know... */
499 
500 	return list_get_nth_element(&input_dev_list, pos);
501 }
502 
503 static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
504 {
505 	return list_get_next_element(&input_dev_list, v, pos);
506 }
507 
508 static void input_devices_seq_stop(struct seq_file *seq, void *v)
509 {
510 	/* release lock here */
511 }
512 
513 static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
514 				   unsigned long *bitmap, int max)
515 {
516 	int i;
517 
518 	for (i = NBITS(max) - 1; i > 0; i--)
519 		if (bitmap[i])
520 			break;
521 
522 	seq_printf(seq, "B: %s=", name);
523 	for (; i >= 0; i--)
524 		seq_printf(seq, "%lx%s", bitmap[i], i > 0 ? " " : "");
525 	seq_putc(seq, '\n');
526 }
527 
528 static int input_devices_seq_show(struct seq_file *seq, void *v)
529 {
530 	struct input_dev *dev = container_of(v, struct input_dev, node);
531 	const char *path = kobject_get_path(&dev->cdev.kobj, GFP_KERNEL);
532 	struct input_handle *handle;
533 
534 	seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
535 		   dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
536 
537 	seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
538 	seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
539 	seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
540 	seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
541 	seq_printf(seq, "H: Handlers=");
542 
543 	list_for_each_entry(handle, &dev->h_list, d_node)
544 		seq_printf(seq, "%s ", handle->name);
545 	seq_putc(seq, '\n');
546 
547 	input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
548 	if (test_bit(EV_KEY, dev->evbit))
549 		input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
550 	if (test_bit(EV_REL, dev->evbit))
551 		input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
552 	if (test_bit(EV_ABS, dev->evbit))
553 		input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
554 	if (test_bit(EV_MSC, dev->evbit))
555 		input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
556 	if (test_bit(EV_LED, dev->evbit))
557 		input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
558 	if (test_bit(EV_SND, dev->evbit))
559 		input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
560 	if (test_bit(EV_FF, dev->evbit))
561 		input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
562 	if (test_bit(EV_SW, dev->evbit))
563 		input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);
564 
565 	seq_putc(seq, '\n');
566 
567 	kfree(path);
568 	return 0;
569 }
570 
571 static struct seq_operations input_devices_seq_ops = {
572 	.start	= input_devices_seq_start,
573 	.next	= input_devices_seq_next,
574 	.stop	= input_devices_seq_stop,
575 	.show	= input_devices_seq_show,
576 };
577 
578 static int input_proc_devices_open(struct inode *inode, struct file *file)
579 {
580 	return seq_open(file, &input_devices_seq_ops);
581 }
582 
583 static const struct file_operations input_devices_fileops = {
584 	.owner		= THIS_MODULE,
585 	.open		= input_proc_devices_open,
586 	.poll		= input_proc_devices_poll,
587 	.read		= seq_read,
588 	.llseek		= seq_lseek,
589 	.release	= seq_release,
590 };
591 
592 static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
593 {
594 	/* acquire lock here ... Yes, we do need locking, I knowi, I know... */
595 	seq->private = (void *)(unsigned long)*pos;
596 	return list_get_nth_element(&input_handler_list, pos);
597 }
598 
599 static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
600 {
601 	seq->private = (void *)(unsigned long)(*pos + 1);
602 	return list_get_next_element(&input_handler_list, v, pos);
603 }
604 
605 static void input_handlers_seq_stop(struct seq_file *seq, void *v)
606 {
607 	/* release lock here */
608 }
609 
610 static int input_handlers_seq_show(struct seq_file *seq, void *v)
611 {
612 	struct input_handler *handler = container_of(v, struct input_handler, node);
613 
614 	seq_printf(seq, "N: Number=%ld Name=%s",
615 		   (unsigned long)seq->private, handler->name);
616 	if (handler->fops)
617 		seq_printf(seq, " Minor=%d", handler->minor);
618 	seq_putc(seq, '\n');
619 
620 	return 0;
621 }
622 static struct seq_operations input_handlers_seq_ops = {
623 	.start	= input_handlers_seq_start,
624 	.next	= input_handlers_seq_next,
625 	.stop	= input_handlers_seq_stop,
626 	.show	= input_handlers_seq_show,
627 };
628 
629 static int input_proc_handlers_open(struct inode *inode, struct file *file)
630 {
631 	return seq_open(file, &input_handlers_seq_ops);
632 }
633 
634 static const struct file_operations input_handlers_fileops = {
635 	.owner		= THIS_MODULE,
636 	.open		= input_proc_handlers_open,
637 	.read		= seq_read,
638 	.llseek		= seq_lseek,
639 	.release	= seq_release,
640 };
641 
642 static int __init input_proc_init(void)
643 {
644 	struct proc_dir_entry *entry;
645 
646 	proc_bus_input_dir = proc_mkdir("input", proc_bus);
647 	if (!proc_bus_input_dir)
648 		return -ENOMEM;
649 
650 	proc_bus_input_dir->owner = THIS_MODULE;
651 
652 	entry = create_proc_entry("devices", 0, proc_bus_input_dir);
653 	if (!entry)
654 		goto fail1;
655 
656 	entry->owner = THIS_MODULE;
657 	entry->proc_fops = &input_devices_fileops;
658 
659 	entry = create_proc_entry("handlers", 0, proc_bus_input_dir);
660 	if (!entry)
661 		goto fail2;
662 
663 	entry->owner = THIS_MODULE;
664 	entry->proc_fops = &input_handlers_fileops;
665 
666 	return 0;
667 
668  fail2:	remove_proc_entry("devices", proc_bus_input_dir);
669  fail1: remove_proc_entry("input", proc_bus);
670 	return -ENOMEM;
671 }
672 
673 static void input_proc_exit(void)
674 {
675 	remove_proc_entry("devices", proc_bus_input_dir);
676 	remove_proc_entry("handlers", proc_bus_input_dir);
677 	remove_proc_entry("input", proc_bus);
678 }
679 
680 #else /* !CONFIG_PROC_FS */
681 static inline void input_wakeup_procfs_readers(void) { }
682 static inline int input_proc_init(void) { return 0; }
683 static inline void input_proc_exit(void) { }
684 #endif
685 
686 #define INPUT_DEV_STRING_ATTR_SHOW(name)					\
687 static ssize_t input_dev_show_##name(struct class_device *dev, char *buf)	\
688 {										\
689 	struct input_dev *input_dev = to_input_dev(dev);			\
690 										\
691 	return scnprintf(buf, PAGE_SIZE, "%s\n",				\
692 			 input_dev->name ? input_dev->name : "");		\
693 }										\
694 static CLASS_DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL);
695 
696 INPUT_DEV_STRING_ATTR_SHOW(name);
697 INPUT_DEV_STRING_ATTR_SHOW(phys);
698 INPUT_DEV_STRING_ATTR_SHOW(uniq);
699 
700 static int input_print_modalias_bits(char *buf, int size,
701 				     char name, unsigned long *bm,
702 				     unsigned int min_bit, unsigned int max_bit)
703 {
704 	int len = 0, i;
705 
706 	len += snprintf(buf, max(size, 0), "%c", name);
707 	for (i = min_bit; i < max_bit; i++)
708 		if (bm[LONG(i)] & BIT(i))
709 			len += snprintf(buf + len, max(size - len, 0), "%X,", i);
710 	return len;
711 }
712 
713 static int input_print_modalias(char *buf, int size, struct input_dev *id,
714 				int add_cr)
715 {
716 	int len;
717 
718 	len = snprintf(buf, max(size, 0),
719 		       "input:b%04Xv%04Xp%04Xe%04X-",
720 		       id->id.bustype, id->id.vendor,
721 		       id->id.product, id->id.version);
722 
723 	len += input_print_modalias_bits(buf + len, size - len,
724 				'e', id->evbit, 0, EV_MAX);
725 	len += input_print_modalias_bits(buf + len, size - len,
726 				'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
727 	len += input_print_modalias_bits(buf + len, size - len,
728 				'r', id->relbit, 0, REL_MAX);
729 	len += input_print_modalias_bits(buf + len, size - len,
730 				'a', id->absbit, 0, ABS_MAX);
731 	len += input_print_modalias_bits(buf + len, size - len,
732 				'm', id->mscbit, 0, MSC_MAX);
733 	len += input_print_modalias_bits(buf + len, size - len,
734 				'l', id->ledbit, 0, LED_MAX);
735 	len += input_print_modalias_bits(buf + len, size - len,
736 				's', id->sndbit, 0, SND_MAX);
737 	len += input_print_modalias_bits(buf + len, size - len,
738 				'f', id->ffbit, 0, FF_MAX);
739 	len += input_print_modalias_bits(buf + len, size - len,
740 				'w', id->swbit, 0, SW_MAX);
741 
742 	if (add_cr)
743 		len += snprintf(buf + len, max(size - len, 0), "\n");
744 
745 	return len;
746 }
747 
748 static ssize_t input_dev_show_modalias(struct class_device *dev, char *buf)
749 {
750 	struct input_dev *id = to_input_dev(dev);
751 	ssize_t len;
752 
753 	len = input_print_modalias(buf, PAGE_SIZE, id, 1);
754 
755 	return min_t(int, len, PAGE_SIZE);
756 }
757 static CLASS_DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
758 
759 static struct attribute *input_dev_attrs[] = {
760 	&class_device_attr_name.attr,
761 	&class_device_attr_phys.attr,
762 	&class_device_attr_uniq.attr,
763 	&class_device_attr_modalias.attr,
764 	NULL
765 };
766 
767 static struct attribute_group input_dev_attr_group = {
768 	.attrs	= input_dev_attrs,
769 };
770 
771 #define INPUT_DEV_ID_ATTR(name)							\
772 static ssize_t input_dev_show_id_##name(struct class_device *dev, char *buf)	\
773 {										\
774 	struct input_dev *input_dev = to_input_dev(dev);			\
775 	return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name);		\
776 }										\
777 static CLASS_DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL);
778 
779 INPUT_DEV_ID_ATTR(bustype);
780 INPUT_DEV_ID_ATTR(vendor);
781 INPUT_DEV_ID_ATTR(product);
782 INPUT_DEV_ID_ATTR(version);
783 
784 static struct attribute *input_dev_id_attrs[] = {
785 	&class_device_attr_bustype.attr,
786 	&class_device_attr_vendor.attr,
787 	&class_device_attr_product.attr,
788 	&class_device_attr_version.attr,
789 	NULL
790 };
791 
792 static struct attribute_group input_dev_id_attr_group = {
793 	.name	= "id",
794 	.attrs	= input_dev_id_attrs,
795 };
796 
797 static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
798 			      int max, int add_cr)
799 {
800 	int i;
801 	int len = 0;
802 
803 	for (i = NBITS(max) - 1; i > 0; i--)
804 		if (bitmap[i])
805 			break;
806 
807 	for (; i >= 0; i--)
808 		len += snprintf(buf + len, max(buf_size - len, 0),
809 				"%lx%s", bitmap[i], i > 0 ? " " : "");
810 
811 	if (add_cr)
812 		len += snprintf(buf + len, max(buf_size - len, 0), "\n");
813 
814 	return len;
815 }
816 
817 #define INPUT_DEV_CAP_ATTR(ev, bm)						\
818 static ssize_t input_dev_show_cap_##bm(struct class_device *dev, char *buf)	\
819 {										\
820 	struct input_dev *input_dev = to_input_dev(dev);			\
821 	int len = input_print_bitmap(buf, PAGE_SIZE,				\
822 				     input_dev->bm##bit, ev##_MAX, 1);		\
823 	return min_t(int, len, PAGE_SIZE);					\
824 }										\
825 static CLASS_DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL);
826 
827 INPUT_DEV_CAP_ATTR(EV, ev);
828 INPUT_DEV_CAP_ATTR(KEY, key);
829 INPUT_DEV_CAP_ATTR(REL, rel);
830 INPUT_DEV_CAP_ATTR(ABS, abs);
831 INPUT_DEV_CAP_ATTR(MSC, msc);
832 INPUT_DEV_CAP_ATTR(LED, led);
833 INPUT_DEV_CAP_ATTR(SND, snd);
834 INPUT_DEV_CAP_ATTR(FF, ff);
835 INPUT_DEV_CAP_ATTR(SW, sw);
836 
837 static struct attribute *input_dev_caps_attrs[] = {
838 	&class_device_attr_ev.attr,
839 	&class_device_attr_key.attr,
840 	&class_device_attr_rel.attr,
841 	&class_device_attr_abs.attr,
842 	&class_device_attr_msc.attr,
843 	&class_device_attr_led.attr,
844 	&class_device_attr_snd.attr,
845 	&class_device_attr_ff.attr,
846 	&class_device_attr_sw.attr,
847 	NULL
848 };
849 
850 static struct attribute_group input_dev_caps_attr_group = {
851 	.name	= "capabilities",
852 	.attrs	= input_dev_caps_attrs,
853 };
854 
855 static struct attribute_group *input_dev_attr_groups[] = {
856 	&input_dev_attr_group,
857 	&input_dev_id_attr_group,
858 	&input_dev_caps_attr_group,
859 	NULL
860 };
861 
862 static void input_dev_release(struct class_device *class_dev)
863 {
864 	struct input_dev *dev = to_input_dev(class_dev);
865 
866 	input_ff_destroy(dev);
867 	kfree(dev);
868 
869 	module_put(THIS_MODULE);
870 }
871 
872 /*
873  * Input uevent interface - loading event handlers based on
874  * device bitfields.
875  */
876 static int input_add_uevent_bm_var(char **envp, int num_envp, int *cur_index,
877 				   char *buffer, int buffer_size, int *cur_len,
878 				   const char *name, unsigned long *bitmap, int max)
879 {
880 	if (*cur_index >= num_envp - 1)
881 		return -ENOMEM;
882 
883 	envp[*cur_index] = buffer + *cur_len;
884 
885 	*cur_len += snprintf(buffer + *cur_len, max(buffer_size - *cur_len, 0), name);
886 	if (*cur_len >= buffer_size)
887 		return -ENOMEM;
888 
889 	*cur_len += input_print_bitmap(buffer + *cur_len,
890 					max(buffer_size - *cur_len, 0),
891 					bitmap, max, 0) + 1;
892 	if (*cur_len > buffer_size)
893 		return -ENOMEM;
894 
895 	(*cur_index)++;
896 	return 0;
897 }
898 
899 static int input_add_uevent_modalias_var(char **envp, int num_envp, int *cur_index,
900 					 char *buffer, int buffer_size, int *cur_len,
901 					 struct input_dev *dev)
902 {
903 	if (*cur_index >= num_envp - 1)
904 		return -ENOMEM;
905 
906 	envp[*cur_index] = buffer + *cur_len;
907 
908 	*cur_len += snprintf(buffer + *cur_len, max(buffer_size - *cur_len, 0),
909 			     "MODALIAS=");
910 	if (*cur_len >= buffer_size)
911 		return -ENOMEM;
912 
913 	*cur_len += input_print_modalias(buffer + *cur_len,
914 					 max(buffer_size - *cur_len, 0),
915 					 dev, 0) + 1;
916 	if (*cur_len > buffer_size)
917 		return -ENOMEM;
918 
919 	(*cur_index)++;
920 	return 0;
921 }
922 
923 #define INPUT_ADD_HOTPLUG_VAR(fmt, val...)				\
924 	do {								\
925 		int err = add_uevent_var(envp, num_envp, &i,		\
926 					buffer, buffer_size, &len,	\
927 					fmt, val);			\
928 		if (err)						\
929 			return err;					\
930 	} while (0)
931 
932 #define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max)				\
933 	do {								\
934 		int err = input_add_uevent_bm_var(envp, num_envp, &i,	\
935 					buffer, buffer_size, &len,	\
936 					name, bm, max);			\
937 		if (err)						\
938 			return err;					\
939 	} while (0)
940 
941 #define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev)				\
942 	do {								\
943 		int err = input_add_uevent_modalias_var(envp,		\
944 					num_envp, &i,			\
945 					buffer, buffer_size, &len,	\
946 					dev);				\
947 		if (err)						\
948 			return err;					\
949 	} while (0)
950 
951 static int input_dev_uevent(struct class_device *cdev, char **envp,
952 			    int num_envp, char *buffer, int buffer_size)
953 {
954 	struct input_dev *dev = to_input_dev(cdev);
955 	int i = 0;
956 	int len = 0;
957 
958 	INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
959 				dev->id.bustype, dev->id.vendor,
960 				dev->id.product, dev->id.version);
961 	if (dev->name)
962 		INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
963 	if (dev->phys)
964 		INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
965 	if (dev->uniq)
966 		INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
967 
968 	INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
969 	if (test_bit(EV_KEY, dev->evbit))
970 		INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
971 	if (test_bit(EV_REL, dev->evbit))
972 		INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
973 	if (test_bit(EV_ABS, dev->evbit))
974 		INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
975 	if (test_bit(EV_MSC, dev->evbit))
976 		INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
977 	if (test_bit(EV_LED, dev->evbit))
978 		INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
979 	if (test_bit(EV_SND, dev->evbit))
980 		INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
981 	if (test_bit(EV_FF, dev->evbit))
982 		INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
983 	if (test_bit(EV_SW, dev->evbit))
984 		INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
985 
986 	INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
987 
988 	envp[i] = NULL;
989 	return 0;
990 }
991 
992 struct class input_class = {
993 	.name			= "input",
994 	.release		= input_dev_release,
995 	.uevent			= input_dev_uevent,
996 };
997 EXPORT_SYMBOL_GPL(input_class);
998 
999 /**
1000  * input_allocate_device - allocate memory for new input device
1001  *
1002  * Returns prepared struct input_dev or NULL.
1003  *
1004  * NOTE: Use input_free_device() to free devices that have not been
1005  * registered; input_unregister_device() should be used for already
1006  * registered devices.
1007  */
1008 struct input_dev *input_allocate_device(void)
1009 {
1010 	struct input_dev *dev;
1011 
1012 	dev = kzalloc(sizeof(struct input_dev), GFP_KERNEL);
1013 	if (dev) {
1014 		dev->cdev.class = &input_class;
1015 		dev->cdev.groups = input_dev_attr_groups;
1016 		class_device_initialize(&dev->cdev);
1017 		mutex_init(&dev->mutex);
1018 		INIT_LIST_HEAD(&dev->h_list);
1019 		INIT_LIST_HEAD(&dev->node);
1020 
1021 		__module_get(THIS_MODULE);
1022 	}
1023 
1024 	return dev;
1025 }
1026 EXPORT_SYMBOL(input_allocate_device);
1027 
1028 /**
1029  * input_free_device - free memory occupied by input_dev structure
1030  * @dev: input device to free
1031  *
1032  * This function should only be used if input_register_device()
1033  * was not called yet or if it failed. Once device was registered
1034  * use input_unregister_device() and memory will be freed once last
1035  * refrence to the device is dropped.
1036  *
1037  * Device should be allocated by input_allocate_device().
1038  *
1039  * NOTE: If there are references to the input device then memory
1040  * will not be freed until last reference is dropped.
1041  */
1042 void input_free_device(struct input_dev *dev)
1043 {
1044 	if (dev)
1045 		input_put_device(dev);
1046 }
1047 EXPORT_SYMBOL(input_free_device);
1048 
1049 /**
1050  * input_set_capability - mark device as capable of a certain event
1051  * @dev: device that is capable of emitting or accepting event
1052  * @type: type of the event (EV_KEY, EV_REL, etc...)
1053  * @code: event code
1054  *
1055  * In addition to setting up corresponding bit in appropriate capability
1056  * bitmap the function also adjusts dev->evbit.
1057  */
1058 void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
1059 {
1060 	switch (type) {
1061 	case EV_KEY:
1062 		__set_bit(code, dev->keybit);
1063 		break;
1064 
1065 	case EV_REL:
1066 		__set_bit(code, dev->relbit);
1067 		break;
1068 
1069 	case EV_ABS:
1070 		__set_bit(code, dev->absbit);
1071 		break;
1072 
1073 	case EV_MSC:
1074 		__set_bit(code, dev->mscbit);
1075 		break;
1076 
1077 	case EV_SW:
1078 		__set_bit(code, dev->swbit);
1079 		break;
1080 
1081 	case EV_LED:
1082 		__set_bit(code, dev->ledbit);
1083 		break;
1084 
1085 	case EV_SND:
1086 		__set_bit(code, dev->sndbit);
1087 		break;
1088 
1089 	case EV_FF:
1090 		__set_bit(code, dev->ffbit);
1091 		break;
1092 
1093 	default:
1094 		printk(KERN_ERR
1095 			"input_set_capability: unknown type %u (code %u)\n",
1096 			type, code);
1097 		dump_stack();
1098 		return;
1099 	}
1100 
1101 	__set_bit(type, dev->evbit);
1102 }
1103 EXPORT_SYMBOL(input_set_capability);
1104 
1105 int input_register_device(struct input_dev *dev)
1106 {
1107 	static atomic_t input_no = ATOMIC_INIT(0);
1108 	struct input_handler *handler;
1109 	const char *path;
1110 	int error;
1111 
1112 	set_bit(EV_SYN, dev->evbit);
1113 
1114 	/*
1115 	 * If delay and period are pre-set by the driver, then autorepeating
1116 	 * is handled by the driver itself and we don't do it in input.c.
1117 	 */
1118 
1119 	init_timer(&dev->timer);
1120 	if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD]) {
1121 		dev->timer.data = (long) dev;
1122 		dev->timer.function = input_repeat_key;
1123 		dev->rep[REP_DELAY] = 250;
1124 		dev->rep[REP_PERIOD] = 33;
1125 	}
1126 
1127 	if (!dev->getkeycode)
1128 		dev->getkeycode = input_default_getkeycode;
1129 
1130 	if (!dev->setkeycode)
1131 		dev->setkeycode = input_default_setkeycode;
1132 
1133 	list_add_tail(&dev->node, &input_dev_list);
1134 
1135 	snprintf(dev->cdev.class_id, sizeof(dev->cdev.class_id),
1136 		 "input%ld", (unsigned long) atomic_inc_return(&input_no) - 1);
1137 
1138 	if (!dev->cdev.dev)
1139 		dev->cdev.dev = dev->dev.parent;
1140 
1141 	error = class_device_add(&dev->cdev);
1142 	if (error)
1143 		return error;
1144 
1145 	path = kobject_get_path(&dev->cdev.kobj, GFP_KERNEL);
1146 	printk(KERN_INFO "input: %s as %s\n",
1147 		dev->name ? dev->name : "Unspecified device", path ? path : "N/A");
1148 	kfree(path);
1149 
1150 	list_for_each_entry(handler, &input_handler_list, node)
1151 		input_attach_handler(dev, handler);
1152 
1153 	input_wakeup_procfs_readers();
1154 
1155 	return 0;
1156 }
1157 EXPORT_SYMBOL(input_register_device);
1158 
1159 void input_unregister_device(struct input_dev *dev)
1160 {
1161 	struct input_handle *handle, *next;
1162 	int code;
1163 
1164 	for (code = 0; code <= KEY_MAX; code++)
1165 		if (test_bit(code, dev->key))
1166 			input_report_key(dev, code, 0);
1167 	input_sync(dev);
1168 
1169 	del_timer_sync(&dev->timer);
1170 
1171 	list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
1172 		handle->handler->disconnect(handle);
1173 	WARN_ON(!list_empty(&dev->h_list));
1174 
1175 	list_del_init(&dev->node);
1176 
1177 	class_device_unregister(&dev->cdev);
1178 
1179 	input_wakeup_procfs_readers();
1180 }
1181 EXPORT_SYMBOL(input_unregister_device);
1182 
1183 int input_register_handler(struct input_handler *handler)
1184 {
1185 	struct input_dev *dev;
1186 
1187 	INIT_LIST_HEAD(&handler->h_list);
1188 
1189 	if (handler->fops != NULL) {
1190 		if (input_table[handler->minor >> 5])
1191 			return -EBUSY;
1192 
1193 		input_table[handler->minor >> 5] = handler;
1194 	}
1195 
1196 	list_add_tail(&handler->node, &input_handler_list);
1197 
1198 	list_for_each_entry(dev, &input_dev_list, node)
1199 		input_attach_handler(dev, handler);
1200 
1201 	input_wakeup_procfs_readers();
1202 	return 0;
1203 }
1204 EXPORT_SYMBOL(input_register_handler);
1205 
1206 void input_unregister_handler(struct input_handler *handler)
1207 {
1208 	struct input_handle *handle, *next;
1209 
1210 	list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
1211 		handler->disconnect(handle);
1212 	WARN_ON(!list_empty(&handler->h_list));
1213 
1214 	list_del_init(&handler->node);
1215 
1216 	if (handler->fops != NULL)
1217 		input_table[handler->minor >> 5] = NULL;
1218 
1219 	input_wakeup_procfs_readers();
1220 }
1221 EXPORT_SYMBOL(input_unregister_handler);
1222 
1223 int input_register_handle(struct input_handle *handle)
1224 {
1225 	struct input_handler *handler = handle->handler;
1226 
1227 	list_add_tail(&handle->d_node, &handle->dev->h_list);
1228 	list_add_tail(&handle->h_node, &handler->h_list);
1229 
1230 	if (handler->start)
1231 		handler->start(handle);
1232 
1233 	return 0;
1234 }
1235 EXPORT_SYMBOL(input_register_handle);
1236 
1237 void input_unregister_handle(struct input_handle *handle)
1238 {
1239 	list_del_init(&handle->h_node);
1240 	list_del_init(&handle->d_node);
1241 }
1242 EXPORT_SYMBOL(input_unregister_handle);
1243 
1244 static int input_open_file(struct inode *inode, struct file *file)
1245 {
1246 	struct input_handler *handler = input_table[iminor(inode) >> 5];
1247 	const struct file_operations *old_fops, *new_fops = NULL;
1248 	int err;
1249 
1250 	/* No load-on-demand here? */
1251 	if (!handler || !(new_fops = fops_get(handler->fops)))
1252 		return -ENODEV;
1253 
1254 	/*
1255 	 * That's _really_ odd. Usually NULL ->open means "nothing special",
1256 	 * not "no device". Oh, well...
1257 	 */
1258 	if (!new_fops->open) {
1259 		fops_put(new_fops);
1260 		return -ENODEV;
1261 	}
1262 	old_fops = file->f_op;
1263 	file->f_op = new_fops;
1264 
1265 	err = new_fops->open(inode, file);
1266 
1267 	if (err) {
1268 		fops_put(file->f_op);
1269 		file->f_op = fops_get(old_fops);
1270 	}
1271 	fops_put(old_fops);
1272 	return err;
1273 }
1274 
1275 static const struct file_operations input_fops = {
1276 	.owner = THIS_MODULE,
1277 	.open = input_open_file,
1278 };
1279 
1280 static int __init input_init(void)
1281 {
1282 	int err;
1283 
1284 	err = class_register(&input_class);
1285 	if (err) {
1286 		printk(KERN_ERR "input: unable to register input_dev class\n");
1287 		return err;
1288 	}
1289 
1290 	err = input_proc_init();
1291 	if (err)
1292 		goto fail1;
1293 
1294 	err = register_chrdev(INPUT_MAJOR, "input", &input_fops);
1295 	if (err) {
1296 		printk(KERN_ERR "input: unable to register char major %d", INPUT_MAJOR);
1297 		goto fail2;
1298 	}
1299 
1300 	return 0;
1301 
1302  fail2:	input_proc_exit();
1303  fail1:	class_unregister(&input_class);
1304 	return err;
1305 }
1306 
1307 static void __exit input_exit(void)
1308 {
1309 	input_proc_exit();
1310 	unregister_chrdev(INPUT_MAJOR, "input");
1311 	class_unregister(&input_class);
1312 }
1313 
1314 subsys_initcall(input_init);
1315 module_exit(input_exit);
1316