xref: /linux/drivers/input/input.c (revision 2b8232ce512105e28453f301d1510de8363bccd1)
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/input.h>
15 #include <linux/module.h>
16 #include <linux/random.h>
17 #include <linux/major.h>
18 #include <linux/proc_fs.h>
19 #include <linux/seq_file.h>
20 #include <linux/interrupt.h>
21 #include <linux/poll.h>
22 #include <linux/device.h>
23 #include <linux/mutex.h>
24 
25 MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
26 MODULE_DESCRIPTION("Input core");
27 MODULE_LICENSE("GPL");
28 
29 #define INPUT_DEVICES	256
30 
31 static LIST_HEAD(input_dev_list);
32 static LIST_HEAD(input_handler_list);
33 
34 static struct input_handler *input_table[8];
35 
36 /**
37  * input_event() - report new input event
38  * @dev: device that generated the event
39  * @type: type of the event
40  * @code: event code
41  * @value: value of the event
42  *
43  * This function should be used by drivers implementing various input devices
44  * See also input_inject_event()
45  */
46 void input_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)
47 {
48 	struct input_handle *handle;
49 
50 	if (type > EV_MAX || !test_bit(type, dev->evbit))
51 		return;
52 
53 	add_input_randomness(type, code, value);
54 
55 	switch (type) {
56 
57 		case EV_SYN:
58 			switch (code) {
59 				case SYN_CONFIG:
60 					if (dev->event)
61 						dev->event(dev, type, code, value);
62 					break;
63 
64 				case SYN_REPORT:
65 					if (dev->sync)
66 						return;
67 					dev->sync = 1;
68 					break;
69 			}
70 			break;
71 
72 		case EV_KEY:
73 
74 			if (code > KEY_MAX || !test_bit(code, dev->keybit) || !!test_bit(code, dev->key) == value)
75 				return;
76 
77 			if (value == 2)
78 				break;
79 
80 			change_bit(code, dev->key);
81 
82 			if (test_bit(EV_REP, dev->evbit) && dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] && dev->timer.data && value) {
83 				dev->repeat_key = code;
84 				mod_timer(&dev->timer, jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
85 			}
86 
87 			break;
88 
89 		case EV_SW:
90 
91 			if (code > SW_MAX || !test_bit(code, dev->swbit) || !!test_bit(code, dev->sw) == value)
92 				return;
93 
94 			change_bit(code, dev->sw);
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)
136 				dev->event(dev, type, code, value);
137 
138 			break;
139 
140 		case EV_LED:
141 
142 			if (code > LED_MAX || !test_bit(code, dev->ledbit) || !!test_bit(code, dev->led) == value)
143 				return;
144 
145 			change_bit(code, dev->led);
146 
147 			if (dev->event)
148 				dev->event(dev, type, code, value);
149 
150 			break;
151 
152 		case EV_SND:
153 
154 			if (code > SND_MAX || !test_bit(code, dev->sndbit))
155 				return;
156 
157 			if (!!test_bit(code, dev->snd) != !!value)
158 				change_bit(code, dev->snd);
159 
160 			if (dev->event)
161 				dev->event(dev, type, code, value);
162 
163 			break;
164 
165 		case EV_REP:
166 
167 			if (code > REP_MAX || value < 0 || dev->rep[code] == value)
168 				return;
169 
170 			dev->rep[code] = value;
171 			if (dev->event)
172 				dev->event(dev, type, code, value);
173 
174 			break;
175 
176 		case EV_FF:
177 
178 			if (value < 0)
179 				return;
180 
181 			if (dev->event)
182 				dev->event(dev, type, code, value);
183 			break;
184 	}
185 
186 	if (type != EV_SYN)
187 		dev->sync = 0;
188 
189 	if (dev->grab)
190 		dev->grab->handler->event(dev->grab, type, code, value);
191 	else
192 		list_for_each_entry(handle, &dev->h_list, d_node)
193 			if (handle->open)
194 				handle->handler->event(handle, type, code, value);
195 }
196 EXPORT_SYMBOL(input_event);
197 
198 /**
199  * input_inject_event() - send input event from input handler
200  * @handle: input handle to send event through
201  * @type: type of the event
202  * @code: event code
203  * @value: value of the event
204  *
205  * Similar to input_event() but will ignore event if device is "grabbed" and handle
206  * injecting event is not the one that owns the device.
207  */
208 void input_inject_event(struct input_handle *handle, unsigned int type, unsigned int code, int value)
209 {
210 	if (!handle->dev->grab || handle->dev->grab == handle)
211 		input_event(handle->dev, type, code, value);
212 }
213 EXPORT_SYMBOL(input_inject_event);
214 
215 static void input_repeat_key(unsigned long data)
216 {
217 	struct input_dev *dev = (void *) data;
218 
219 	if (!test_bit(dev->repeat_key, dev->key))
220 		return;
221 
222 	input_event(dev, EV_KEY, dev->repeat_key, 2);
223 	input_sync(dev);
224 
225 	if (dev->rep[REP_PERIOD])
226 		mod_timer(&dev->timer, jiffies + msecs_to_jiffies(dev->rep[REP_PERIOD]));
227 }
228 
229 int input_grab_device(struct input_handle *handle)
230 {
231 	if (handle->dev->grab)
232 		return -EBUSY;
233 
234 	handle->dev->grab = handle;
235 	return 0;
236 }
237 EXPORT_SYMBOL(input_grab_device);
238 
239 void input_release_device(struct input_handle *handle)
240 {
241 	struct input_dev *dev = handle->dev;
242 
243 	if (dev->grab == handle) {
244 		dev->grab = NULL;
245 
246 		list_for_each_entry(handle, &dev->h_list, d_node)
247 			if (handle->handler->start)
248 				handle->handler->start(handle);
249 	}
250 }
251 EXPORT_SYMBOL(input_release_device);
252 
253 int input_open_device(struct input_handle *handle)
254 {
255 	struct input_dev *dev = handle->dev;
256 	int err;
257 
258 	err = mutex_lock_interruptible(&dev->mutex);
259 	if (err)
260 		return err;
261 
262 	handle->open++;
263 
264 	if (!dev->users++ && dev->open)
265 		err = dev->open(dev);
266 
267 	if (err)
268 		handle->open--;
269 
270 	mutex_unlock(&dev->mutex);
271 
272 	return err;
273 }
274 EXPORT_SYMBOL(input_open_device);
275 
276 int input_flush_device(struct input_handle* handle, struct file* file)
277 {
278 	if (handle->dev->flush)
279 		return handle->dev->flush(handle->dev, file);
280 
281 	return 0;
282 }
283 EXPORT_SYMBOL(input_flush_device);
284 
285 void input_close_device(struct input_handle *handle)
286 {
287 	struct input_dev *dev = handle->dev;
288 
289 	input_release_device(handle);
290 
291 	mutex_lock(&dev->mutex);
292 
293 	if (!--dev->users && dev->close)
294 		dev->close(dev);
295 	handle->open--;
296 
297 	mutex_unlock(&dev->mutex);
298 }
299 EXPORT_SYMBOL(input_close_device);
300 
301 static int input_fetch_keycode(struct input_dev *dev, int scancode)
302 {
303 	switch (dev->keycodesize) {
304 		case 1:
305 			return ((u8 *)dev->keycode)[scancode];
306 
307 		case 2:
308 			return ((u16 *)dev->keycode)[scancode];
309 
310 		default:
311 			return ((u32 *)dev->keycode)[scancode];
312 	}
313 }
314 
315 static int input_default_getkeycode(struct input_dev *dev,
316 				    int scancode, int *keycode)
317 {
318 	if (!dev->keycodesize)
319 		return -EINVAL;
320 
321 	if (scancode < 0 || scancode >= dev->keycodemax)
322 		return -EINVAL;
323 
324 	*keycode = input_fetch_keycode(dev, scancode);
325 
326 	return 0;
327 }
328 
329 static int input_default_setkeycode(struct input_dev *dev,
330 				    int scancode, int keycode)
331 {
332 	int old_keycode;
333 	int i;
334 
335 	if (scancode < 0 || scancode >= dev->keycodemax)
336 		return -EINVAL;
337 
338 	if (keycode < 0 || keycode > KEY_MAX)
339 		return -EINVAL;
340 
341 	if (!dev->keycodesize)
342 		return -EINVAL;
343 
344 	if (dev->keycodesize < sizeof(keycode) && (keycode >> (dev->keycodesize * 8)))
345 		return -EINVAL;
346 
347 	switch (dev->keycodesize) {
348 		case 1: {
349 			u8 *k = (u8 *)dev->keycode;
350 			old_keycode = k[scancode];
351 			k[scancode] = keycode;
352 			break;
353 		}
354 		case 2: {
355 			u16 *k = (u16 *)dev->keycode;
356 			old_keycode = k[scancode];
357 			k[scancode] = keycode;
358 			break;
359 		}
360 		default: {
361 			u32 *k = (u32 *)dev->keycode;
362 			old_keycode = k[scancode];
363 			k[scancode] = keycode;
364 			break;
365 		}
366 	}
367 
368 	clear_bit(old_keycode, dev->keybit);
369 	set_bit(keycode, dev->keybit);
370 
371 	for (i = 0; i < dev->keycodemax; i++) {
372 		if (input_fetch_keycode(dev, i) == old_keycode) {
373 			set_bit(old_keycode, dev->keybit);
374 			break; /* Setting the bit twice is useless, so break */
375 		}
376 	}
377 
378 	return 0;
379 }
380 
381 
382 #define MATCH_BIT(bit, max) \
383 		for (i = 0; i < NBITS(max); i++) \
384 			if ((id->bit[i] & dev->bit[i]) != id->bit[i]) \
385 				break; \
386 		if (i != NBITS(max)) \
387 			continue;
388 
389 static const struct input_device_id *input_match_device(const struct input_device_id *id,
390 							struct input_dev *dev)
391 {
392 	int i;
393 
394 	for (; id->flags || id->driver_info; id++) {
395 
396 		if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
397 			if (id->bustype != dev->id.bustype)
398 				continue;
399 
400 		if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
401 			if (id->vendor != dev->id.vendor)
402 				continue;
403 
404 		if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
405 			if (id->product != dev->id.product)
406 				continue;
407 
408 		if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
409 			if (id->version != dev->id.version)
410 				continue;
411 
412 		MATCH_BIT(evbit,  EV_MAX);
413 		MATCH_BIT(keybit, KEY_MAX);
414 		MATCH_BIT(relbit, REL_MAX);
415 		MATCH_BIT(absbit, ABS_MAX);
416 		MATCH_BIT(mscbit, MSC_MAX);
417 		MATCH_BIT(ledbit, LED_MAX);
418 		MATCH_BIT(sndbit, SND_MAX);
419 		MATCH_BIT(ffbit,  FF_MAX);
420 		MATCH_BIT(swbit,  SW_MAX);
421 
422 		return id;
423 	}
424 
425 	return NULL;
426 }
427 
428 static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
429 {
430 	const struct input_device_id *id;
431 	int error;
432 
433 	if (handler->blacklist && input_match_device(handler->blacklist, dev))
434 		return -ENODEV;
435 
436 	id = input_match_device(handler->id_table, dev);
437 	if (!id)
438 		return -ENODEV;
439 
440 	error = handler->connect(handler, dev, id);
441 	if (error && error != -ENODEV)
442 		printk(KERN_ERR
443 			"input: failed to attach handler %s to device %s, "
444 			"error: %d\n",
445 			handler->name, kobject_name(&dev->dev.kobj), error);
446 
447 	return error;
448 }
449 
450 
451 #ifdef CONFIG_PROC_FS
452 
453 static struct proc_dir_entry *proc_bus_input_dir;
454 static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
455 static int input_devices_state;
456 
457 static inline void input_wakeup_procfs_readers(void)
458 {
459 	input_devices_state++;
460 	wake_up(&input_devices_poll_wait);
461 }
462 
463 static unsigned int input_proc_devices_poll(struct file *file, poll_table *wait)
464 {
465 	int state = input_devices_state;
466 
467 	poll_wait(file, &input_devices_poll_wait, wait);
468 	if (state != input_devices_state)
469 		return POLLIN | POLLRDNORM;
470 
471 	return 0;
472 }
473 
474 static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
475 {
476 	/* acquire lock here ... Yes, we do need locking, I knowi, I know... */
477 
478 	return seq_list_start(&input_dev_list, *pos);
479 }
480 
481 static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
482 {
483 	return seq_list_next(v, &input_dev_list, pos);
484 }
485 
486 static void input_devices_seq_stop(struct seq_file *seq, void *v)
487 {
488 	/* release lock here */
489 }
490 
491 static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
492 				   unsigned long *bitmap, int max)
493 {
494 	int i;
495 
496 	for (i = NBITS(max) - 1; i > 0; i--)
497 		if (bitmap[i])
498 			break;
499 
500 	seq_printf(seq, "B: %s=", name);
501 	for (; i >= 0; i--)
502 		seq_printf(seq, "%lx%s", bitmap[i], i > 0 ? " " : "");
503 	seq_putc(seq, '\n');
504 }
505 
506 static int input_devices_seq_show(struct seq_file *seq, void *v)
507 {
508 	struct input_dev *dev = container_of(v, struct input_dev, node);
509 	const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
510 	struct input_handle *handle;
511 
512 	seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
513 		   dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
514 
515 	seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
516 	seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
517 	seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
518 	seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
519 	seq_printf(seq, "H: Handlers=");
520 
521 	list_for_each_entry(handle, &dev->h_list, d_node)
522 		seq_printf(seq, "%s ", handle->name);
523 	seq_putc(seq, '\n');
524 
525 	input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
526 	if (test_bit(EV_KEY, dev->evbit))
527 		input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
528 	if (test_bit(EV_REL, dev->evbit))
529 		input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
530 	if (test_bit(EV_ABS, dev->evbit))
531 		input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
532 	if (test_bit(EV_MSC, dev->evbit))
533 		input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
534 	if (test_bit(EV_LED, dev->evbit))
535 		input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
536 	if (test_bit(EV_SND, dev->evbit))
537 		input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
538 	if (test_bit(EV_FF, dev->evbit))
539 		input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
540 	if (test_bit(EV_SW, dev->evbit))
541 		input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);
542 
543 	seq_putc(seq, '\n');
544 
545 	kfree(path);
546 	return 0;
547 }
548 
549 static struct seq_operations input_devices_seq_ops = {
550 	.start	= input_devices_seq_start,
551 	.next	= input_devices_seq_next,
552 	.stop	= input_devices_seq_stop,
553 	.show	= input_devices_seq_show,
554 };
555 
556 static int input_proc_devices_open(struct inode *inode, struct file *file)
557 {
558 	return seq_open(file, &input_devices_seq_ops);
559 }
560 
561 static const struct file_operations input_devices_fileops = {
562 	.owner		= THIS_MODULE,
563 	.open		= input_proc_devices_open,
564 	.poll		= input_proc_devices_poll,
565 	.read		= seq_read,
566 	.llseek		= seq_lseek,
567 	.release	= seq_release,
568 };
569 
570 static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
571 {
572 	/* acquire lock here ... Yes, we do need locking, I knowi, I know... */
573 	seq->private = (void *)(unsigned long)*pos;
574 	return seq_list_start(&input_handler_list, *pos);
575 }
576 
577 static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
578 {
579 	seq->private = (void *)(unsigned long)(*pos + 1);
580 	return seq_list_next(v, &input_handler_list, pos);
581 }
582 
583 static void input_handlers_seq_stop(struct seq_file *seq, void *v)
584 {
585 	/* release lock here */
586 }
587 
588 static int input_handlers_seq_show(struct seq_file *seq, void *v)
589 {
590 	struct input_handler *handler = container_of(v, struct input_handler, node);
591 
592 	seq_printf(seq, "N: Number=%ld Name=%s",
593 		   (unsigned long)seq->private, handler->name);
594 	if (handler->fops)
595 		seq_printf(seq, " Minor=%d", handler->minor);
596 	seq_putc(seq, '\n');
597 
598 	return 0;
599 }
600 static struct seq_operations input_handlers_seq_ops = {
601 	.start	= input_handlers_seq_start,
602 	.next	= input_handlers_seq_next,
603 	.stop	= input_handlers_seq_stop,
604 	.show	= input_handlers_seq_show,
605 };
606 
607 static int input_proc_handlers_open(struct inode *inode, struct file *file)
608 {
609 	return seq_open(file, &input_handlers_seq_ops);
610 }
611 
612 static const struct file_operations input_handlers_fileops = {
613 	.owner		= THIS_MODULE,
614 	.open		= input_proc_handlers_open,
615 	.read		= seq_read,
616 	.llseek		= seq_lseek,
617 	.release	= seq_release,
618 };
619 
620 static int __init input_proc_init(void)
621 {
622 	struct proc_dir_entry *entry;
623 
624 	proc_bus_input_dir = proc_mkdir("input", proc_bus);
625 	if (!proc_bus_input_dir)
626 		return -ENOMEM;
627 
628 	proc_bus_input_dir->owner = THIS_MODULE;
629 
630 	entry = create_proc_entry("devices", 0, proc_bus_input_dir);
631 	if (!entry)
632 		goto fail1;
633 
634 	entry->owner = THIS_MODULE;
635 	entry->proc_fops = &input_devices_fileops;
636 
637 	entry = create_proc_entry("handlers", 0, proc_bus_input_dir);
638 	if (!entry)
639 		goto fail2;
640 
641 	entry->owner = THIS_MODULE;
642 	entry->proc_fops = &input_handlers_fileops;
643 
644 	return 0;
645 
646  fail2:	remove_proc_entry("devices", proc_bus_input_dir);
647  fail1: remove_proc_entry("input", proc_bus);
648 	return -ENOMEM;
649 }
650 
651 static void input_proc_exit(void)
652 {
653 	remove_proc_entry("devices", proc_bus_input_dir);
654 	remove_proc_entry("handlers", proc_bus_input_dir);
655 	remove_proc_entry("input", proc_bus);
656 }
657 
658 #else /* !CONFIG_PROC_FS */
659 static inline void input_wakeup_procfs_readers(void) { }
660 static inline int input_proc_init(void) { return 0; }
661 static inline void input_proc_exit(void) { }
662 #endif
663 
664 #define INPUT_DEV_STRING_ATTR_SHOW(name)				\
665 static ssize_t input_dev_show_##name(struct device *dev,		\
666 				     struct device_attribute *attr,	\
667 				     char *buf)				\
668 {									\
669 	struct input_dev *input_dev = to_input_dev(dev);		\
670 									\
671 	return scnprintf(buf, PAGE_SIZE, "%s\n",			\
672 			 input_dev->name ? input_dev->name : "");	\
673 }									\
674 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
675 
676 INPUT_DEV_STRING_ATTR_SHOW(name);
677 INPUT_DEV_STRING_ATTR_SHOW(phys);
678 INPUT_DEV_STRING_ATTR_SHOW(uniq);
679 
680 static int input_print_modalias_bits(char *buf, int size,
681 				     char name, unsigned long *bm,
682 				     unsigned int min_bit, unsigned int max_bit)
683 {
684 	int len = 0, i;
685 
686 	len += snprintf(buf, max(size, 0), "%c", name);
687 	for (i = min_bit; i < max_bit; i++)
688 		if (bm[LONG(i)] & BIT(i))
689 			len += snprintf(buf + len, max(size - len, 0), "%X,", i);
690 	return len;
691 }
692 
693 static int input_print_modalias(char *buf, int size, struct input_dev *id,
694 				int add_cr)
695 {
696 	int len;
697 
698 	len = snprintf(buf, max(size, 0),
699 		       "input:b%04Xv%04Xp%04Xe%04X-",
700 		       id->id.bustype, id->id.vendor,
701 		       id->id.product, id->id.version);
702 
703 	len += input_print_modalias_bits(buf + len, size - len,
704 				'e', id->evbit, 0, EV_MAX);
705 	len += input_print_modalias_bits(buf + len, size - len,
706 				'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
707 	len += input_print_modalias_bits(buf + len, size - len,
708 				'r', id->relbit, 0, REL_MAX);
709 	len += input_print_modalias_bits(buf + len, size - len,
710 				'a', id->absbit, 0, ABS_MAX);
711 	len += input_print_modalias_bits(buf + len, size - len,
712 				'm', id->mscbit, 0, MSC_MAX);
713 	len += input_print_modalias_bits(buf + len, size - len,
714 				'l', id->ledbit, 0, LED_MAX);
715 	len += input_print_modalias_bits(buf + len, size - len,
716 				's', id->sndbit, 0, SND_MAX);
717 	len += input_print_modalias_bits(buf + len, size - len,
718 				'f', id->ffbit, 0, FF_MAX);
719 	len += input_print_modalias_bits(buf + len, size - len,
720 				'w', id->swbit, 0, SW_MAX);
721 
722 	if (add_cr)
723 		len += snprintf(buf + len, max(size - len, 0), "\n");
724 
725 	return len;
726 }
727 
728 static ssize_t input_dev_show_modalias(struct device *dev,
729 				       struct device_attribute *attr,
730 				       char *buf)
731 {
732 	struct input_dev *id = to_input_dev(dev);
733 	ssize_t len;
734 
735 	len = input_print_modalias(buf, PAGE_SIZE, id, 1);
736 
737 	return min_t(int, len, PAGE_SIZE);
738 }
739 static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
740 
741 static struct attribute *input_dev_attrs[] = {
742 	&dev_attr_name.attr,
743 	&dev_attr_phys.attr,
744 	&dev_attr_uniq.attr,
745 	&dev_attr_modalias.attr,
746 	NULL
747 };
748 
749 static struct attribute_group input_dev_attr_group = {
750 	.attrs	= input_dev_attrs,
751 };
752 
753 #define INPUT_DEV_ID_ATTR(name)						\
754 static ssize_t input_dev_show_id_##name(struct device *dev,		\
755 					struct device_attribute *attr,	\
756 					char *buf)			\
757 {									\
758 	struct input_dev *input_dev = to_input_dev(dev);		\
759 	return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name);	\
760 }									\
761 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
762 
763 INPUT_DEV_ID_ATTR(bustype);
764 INPUT_DEV_ID_ATTR(vendor);
765 INPUT_DEV_ID_ATTR(product);
766 INPUT_DEV_ID_ATTR(version);
767 
768 static struct attribute *input_dev_id_attrs[] = {
769 	&dev_attr_bustype.attr,
770 	&dev_attr_vendor.attr,
771 	&dev_attr_product.attr,
772 	&dev_attr_version.attr,
773 	NULL
774 };
775 
776 static struct attribute_group input_dev_id_attr_group = {
777 	.name	= "id",
778 	.attrs	= input_dev_id_attrs,
779 };
780 
781 static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
782 			      int max, int add_cr)
783 {
784 	int i;
785 	int len = 0;
786 
787 	for (i = NBITS(max) - 1; i > 0; i--)
788 		if (bitmap[i])
789 			break;
790 
791 	for (; i >= 0; i--)
792 		len += snprintf(buf + len, max(buf_size - len, 0),
793 				"%lx%s", bitmap[i], i > 0 ? " " : "");
794 
795 	if (add_cr)
796 		len += snprintf(buf + len, max(buf_size - len, 0), "\n");
797 
798 	return len;
799 }
800 
801 #define INPUT_DEV_CAP_ATTR(ev, bm)					\
802 static ssize_t input_dev_show_cap_##bm(struct device *dev,		\
803 				       struct device_attribute *attr,	\
804 				       char *buf)			\
805 {									\
806 	struct input_dev *input_dev = to_input_dev(dev);		\
807 	int len = input_print_bitmap(buf, PAGE_SIZE,			\
808 				     input_dev->bm##bit, ev##_MAX, 1);	\
809 	return min_t(int, len, PAGE_SIZE);				\
810 }									\
811 static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
812 
813 INPUT_DEV_CAP_ATTR(EV, ev);
814 INPUT_DEV_CAP_ATTR(KEY, key);
815 INPUT_DEV_CAP_ATTR(REL, rel);
816 INPUT_DEV_CAP_ATTR(ABS, abs);
817 INPUT_DEV_CAP_ATTR(MSC, msc);
818 INPUT_DEV_CAP_ATTR(LED, led);
819 INPUT_DEV_CAP_ATTR(SND, snd);
820 INPUT_DEV_CAP_ATTR(FF, ff);
821 INPUT_DEV_CAP_ATTR(SW, sw);
822 
823 static struct attribute *input_dev_caps_attrs[] = {
824 	&dev_attr_ev.attr,
825 	&dev_attr_key.attr,
826 	&dev_attr_rel.attr,
827 	&dev_attr_abs.attr,
828 	&dev_attr_msc.attr,
829 	&dev_attr_led.attr,
830 	&dev_attr_snd.attr,
831 	&dev_attr_ff.attr,
832 	&dev_attr_sw.attr,
833 	NULL
834 };
835 
836 static struct attribute_group input_dev_caps_attr_group = {
837 	.name	= "capabilities",
838 	.attrs	= input_dev_caps_attrs,
839 };
840 
841 static struct attribute_group *input_dev_attr_groups[] = {
842 	&input_dev_attr_group,
843 	&input_dev_id_attr_group,
844 	&input_dev_caps_attr_group,
845 	NULL
846 };
847 
848 static void input_dev_release(struct device *device)
849 {
850 	struct input_dev *dev = to_input_dev(device);
851 
852 	input_ff_destroy(dev);
853 	kfree(dev);
854 
855 	module_put(THIS_MODULE);
856 }
857 
858 /*
859  * Input uevent interface - loading event handlers based on
860  * device bitfields.
861  */
862 static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
863 				   const char *name, unsigned long *bitmap, int max)
864 {
865 	int len;
866 
867 	if (add_uevent_var(env, "%s=", name))
868 		return -ENOMEM;
869 
870 	len = input_print_bitmap(&env->buf[env->buflen - 1],
871 				 sizeof(env->buf) - env->buflen,
872 				 bitmap, max, 0);
873 	if (len >= (sizeof(env->buf) - env->buflen))
874 		return -ENOMEM;
875 
876 	env->buflen += len;
877 	return 0;
878 }
879 
880 static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
881 					 struct input_dev *dev)
882 {
883 	int len;
884 
885 	if (add_uevent_var(env, "MODALIAS="))
886 		return -ENOMEM;
887 
888 	len = input_print_modalias(&env->buf[env->buflen - 1],
889 				   sizeof(env->buf) - env->buflen,
890 				   dev, 0);
891 	if (len >= (sizeof(env->buf) - env->buflen))
892 		return -ENOMEM;
893 
894 	env->buflen += len;
895 	return 0;
896 }
897 
898 #define INPUT_ADD_HOTPLUG_VAR(fmt, val...)				\
899 	do {								\
900 		int err = add_uevent_var(env, fmt, val);		\
901 		if (err)						\
902 			return err;					\
903 	} while (0)
904 
905 #define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max)				\
906 	do {								\
907 		int err = input_add_uevent_bm_var(env, name, bm, max);	\
908 		if (err)						\
909 			return err;					\
910 	} while (0)
911 
912 #define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev)				\
913 	do {								\
914 		int err = input_add_uevent_modalias_var(env, dev);	\
915 		if (err)						\
916 			return err;					\
917 	} while (0)
918 
919 static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
920 {
921 	struct input_dev *dev = to_input_dev(device);
922 
923 	INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
924 				dev->id.bustype, dev->id.vendor,
925 				dev->id.product, dev->id.version);
926 	if (dev->name)
927 		INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
928 	if (dev->phys)
929 		INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
930 	if (dev->uniq)
931 		INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
932 
933 	INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
934 	if (test_bit(EV_KEY, dev->evbit))
935 		INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
936 	if (test_bit(EV_REL, dev->evbit))
937 		INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
938 	if (test_bit(EV_ABS, dev->evbit))
939 		INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
940 	if (test_bit(EV_MSC, dev->evbit))
941 		INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
942 	if (test_bit(EV_LED, dev->evbit))
943 		INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
944 	if (test_bit(EV_SND, dev->evbit))
945 		INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
946 	if (test_bit(EV_FF, dev->evbit))
947 		INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
948 	if (test_bit(EV_SW, dev->evbit))
949 		INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
950 
951 	INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
952 
953 	return 0;
954 }
955 
956 static struct device_type input_dev_type = {
957 	.groups		= input_dev_attr_groups,
958 	.release	= input_dev_release,
959 	.uevent		= input_dev_uevent,
960 };
961 
962 struct class input_class = {
963 	.name		= "input",
964 };
965 EXPORT_SYMBOL_GPL(input_class);
966 
967 /**
968  * input_allocate_device - allocate memory for new input device
969  *
970  * Returns prepared struct input_dev or NULL.
971  *
972  * NOTE: Use input_free_device() to free devices that have not been
973  * registered; input_unregister_device() should be used for already
974  * registered devices.
975  */
976 struct input_dev *input_allocate_device(void)
977 {
978 	struct input_dev *dev;
979 
980 	dev = kzalloc(sizeof(struct input_dev), GFP_KERNEL);
981 	if (dev) {
982 		dev->dev.type = &input_dev_type;
983 		dev->dev.class = &input_class;
984 		device_initialize(&dev->dev);
985 		mutex_init(&dev->mutex);
986 		INIT_LIST_HEAD(&dev->h_list);
987 		INIT_LIST_HEAD(&dev->node);
988 
989 		__module_get(THIS_MODULE);
990 	}
991 
992 	return dev;
993 }
994 EXPORT_SYMBOL(input_allocate_device);
995 
996 /**
997  * input_free_device - free memory occupied by input_dev structure
998  * @dev: input device to free
999  *
1000  * This function should only be used if input_register_device()
1001  * was not called yet or if it failed. Once device was registered
1002  * use input_unregister_device() and memory will be freed once last
1003  * refrence to the device is dropped.
1004  *
1005  * Device should be allocated by input_allocate_device().
1006  *
1007  * NOTE: If there are references to the input device then memory
1008  * will not be freed until last reference is dropped.
1009  */
1010 void input_free_device(struct input_dev *dev)
1011 {
1012 	if (dev)
1013 		input_put_device(dev);
1014 }
1015 EXPORT_SYMBOL(input_free_device);
1016 
1017 /**
1018  * input_set_capability - mark device as capable of a certain event
1019  * @dev: device that is capable of emitting or accepting event
1020  * @type: type of the event (EV_KEY, EV_REL, etc...)
1021  * @code: event code
1022  *
1023  * In addition to setting up corresponding bit in appropriate capability
1024  * bitmap the function also adjusts dev->evbit.
1025  */
1026 void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
1027 {
1028 	switch (type) {
1029 	case EV_KEY:
1030 		__set_bit(code, dev->keybit);
1031 		break;
1032 
1033 	case EV_REL:
1034 		__set_bit(code, dev->relbit);
1035 		break;
1036 
1037 	case EV_ABS:
1038 		__set_bit(code, dev->absbit);
1039 		break;
1040 
1041 	case EV_MSC:
1042 		__set_bit(code, dev->mscbit);
1043 		break;
1044 
1045 	case EV_SW:
1046 		__set_bit(code, dev->swbit);
1047 		break;
1048 
1049 	case EV_LED:
1050 		__set_bit(code, dev->ledbit);
1051 		break;
1052 
1053 	case EV_SND:
1054 		__set_bit(code, dev->sndbit);
1055 		break;
1056 
1057 	case EV_FF:
1058 		__set_bit(code, dev->ffbit);
1059 		break;
1060 
1061 	default:
1062 		printk(KERN_ERR
1063 			"input_set_capability: unknown type %u (code %u)\n",
1064 			type, code);
1065 		dump_stack();
1066 		return;
1067 	}
1068 
1069 	__set_bit(type, dev->evbit);
1070 }
1071 EXPORT_SYMBOL(input_set_capability);
1072 
1073 int input_register_device(struct input_dev *dev)
1074 {
1075 	static atomic_t input_no = ATOMIC_INIT(0);
1076 	struct input_handler *handler;
1077 	const char *path;
1078 	int error;
1079 
1080 	set_bit(EV_SYN, dev->evbit);
1081 
1082 	/*
1083 	 * If delay and period are pre-set by the driver, then autorepeating
1084 	 * is handled by the driver itself and we don't do it in input.c.
1085 	 */
1086 
1087 	init_timer(&dev->timer);
1088 	if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD]) {
1089 		dev->timer.data = (long) dev;
1090 		dev->timer.function = input_repeat_key;
1091 		dev->rep[REP_DELAY] = 250;
1092 		dev->rep[REP_PERIOD] = 33;
1093 	}
1094 
1095 	if (!dev->getkeycode)
1096 		dev->getkeycode = input_default_getkeycode;
1097 
1098 	if (!dev->setkeycode)
1099 		dev->setkeycode = input_default_setkeycode;
1100 
1101 	list_add_tail(&dev->node, &input_dev_list);
1102 
1103 	snprintf(dev->dev.bus_id, sizeof(dev->dev.bus_id),
1104 		 "input%ld", (unsigned long) atomic_inc_return(&input_no) - 1);
1105 
1106 	if (dev->cdev.dev)
1107 		dev->dev.parent = dev->cdev.dev;
1108 
1109 	error = device_add(&dev->dev);
1110 	if (error)
1111 		return error;
1112 
1113 	path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1114 	printk(KERN_INFO "input: %s as %s\n",
1115 		dev->name ? dev->name : "Unspecified device", path ? path : "N/A");
1116 	kfree(path);
1117 
1118 	list_for_each_entry(handler, &input_handler_list, node)
1119 		input_attach_handler(dev, handler);
1120 
1121 	input_wakeup_procfs_readers();
1122 
1123 	return 0;
1124 }
1125 EXPORT_SYMBOL(input_register_device);
1126 
1127 void input_unregister_device(struct input_dev *dev)
1128 {
1129 	struct input_handle *handle, *next;
1130 	int code;
1131 
1132 	for (code = 0; code <= KEY_MAX; code++)
1133 		if (test_bit(code, dev->key))
1134 			input_report_key(dev, code, 0);
1135 	input_sync(dev);
1136 
1137 	del_timer_sync(&dev->timer);
1138 
1139 	list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
1140 		handle->handler->disconnect(handle);
1141 	WARN_ON(!list_empty(&dev->h_list));
1142 
1143 	list_del_init(&dev->node);
1144 
1145 	device_unregister(&dev->dev);
1146 
1147 	input_wakeup_procfs_readers();
1148 }
1149 EXPORT_SYMBOL(input_unregister_device);
1150 
1151 int input_register_handler(struct input_handler *handler)
1152 {
1153 	struct input_dev *dev;
1154 
1155 	INIT_LIST_HEAD(&handler->h_list);
1156 
1157 	if (handler->fops != NULL) {
1158 		if (input_table[handler->minor >> 5])
1159 			return -EBUSY;
1160 
1161 		input_table[handler->minor >> 5] = handler;
1162 	}
1163 
1164 	list_add_tail(&handler->node, &input_handler_list);
1165 
1166 	list_for_each_entry(dev, &input_dev_list, node)
1167 		input_attach_handler(dev, handler);
1168 
1169 	input_wakeup_procfs_readers();
1170 	return 0;
1171 }
1172 EXPORT_SYMBOL(input_register_handler);
1173 
1174 void input_unregister_handler(struct input_handler *handler)
1175 {
1176 	struct input_handle *handle, *next;
1177 
1178 	list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
1179 		handler->disconnect(handle);
1180 	WARN_ON(!list_empty(&handler->h_list));
1181 
1182 	list_del_init(&handler->node);
1183 
1184 	if (handler->fops != NULL)
1185 		input_table[handler->minor >> 5] = NULL;
1186 
1187 	input_wakeup_procfs_readers();
1188 }
1189 EXPORT_SYMBOL(input_unregister_handler);
1190 
1191 int input_register_handle(struct input_handle *handle)
1192 {
1193 	struct input_handler *handler = handle->handler;
1194 
1195 	list_add_tail(&handle->d_node, &handle->dev->h_list);
1196 	list_add_tail(&handle->h_node, &handler->h_list);
1197 
1198 	if (handler->start)
1199 		handler->start(handle);
1200 
1201 	return 0;
1202 }
1203 EXPORT_SYMBOL(input_register_handle);
1204 
1205 void input_unregister_handle(struct input_handle *handle)
1206 {
1207 	list_del_init(&handle->h_node);
1208 	list_del_init(&handle->d_node);
1209 }
1210 EXPORT_SYMBOL(input_unregister_handle);
1211 
1212 static int input_open_file(struct inode *inode, struct file *file)
1213 {
1214 	struct input_handler *handler = input_table[iminor(inode) >> 5];
1215 	const struct file_operations *old_fops, *new_fops = NULL;
1216 	int err;
1217 
1218 	/* No load-on-demand here? */
1219 	if (!handler || !(new_fops = fops_get(handler->fops)))
1220 		return -ENODEV;
1221 
1222 	/*
1223 	 * That's _really_ odd. Usually NULL ->open means "nothing special",
1224 	 * not "no device". Oh, well...
1225 	 */
1226 	if (!new_fops->open) {
1227 		fops_put(new_fops);
1228 		return -ENODEV;
1229 	}
1230 	old_fops = file->f_op;
1231 	file->f_op = new_fops;
1232 
1233 	err = new_fops->open(inode, file);
1234 
1235 	if (err) {
1236 		fops_put(file->f_op);
1237 		file->f_op = fops_get(old_fops);
1238 	}
1239 	fops_put(old_fops);
1240 	return err;
1241 }
1242 
1243 static const struct file_operations input_fops = {
1244 	.owner = THIS_MODULE,
1245 	.open = input_open_file,
1246 };
1247 
1248 static int __init input_init(void)
1249 {
1250 	int err;
1251 
1252 	err = class_register(&input_class);
1253 	if (err) {
1254 		printk(KERN_ERR "input: unable to register input_dev class\n");
1255 		return err;
1256 	}
1257 
1258 	err = input_proc_init();
1259 	if (err)
1260 		goto fail1;
1261 
1262 	err = register_chrdev(INPUT_MAJOR, "input", &input_fops);
1263 	if (err) {
1264 		printk(KERN_ERR "input: unable to register char major %d", INPUT_MAJOR);
1265 		goto fail2;
1266 	}
1267 
1268 	return 0;
1269 
1270  fail2:	input_proc_exit();
1271  fail1:	class_unregister(&input_class);
1272 	return err;
1273 }
1274 
1275 static void __exit input_exit(void)
1276 {
1277 	input_proc_exit();
1278 	unregister_chrdev(INPUT_MAJOR, "input");
1279 	class_unregister(&input_class);
1280 }
1281 
1282 subsys_initcall(input_init);
1283 module_exit(input_exit);
1284