xref: /openbmc/linux/drivers/input/input.c (revision 64c70b1c)
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 struct list_head *list_get_nth_element(struct list_head *list, loff_t *pos)
475 {
476 	struct list_head *node;
477 	loff_t i = 0;
478 
479 	list_for_each(node, list)
480 		if (i++ == *pos)
481 			return node;
482 
483 	return NULL;
484 }
485 
486 static struct list_head *list_get_next_element(struct list_head *list, struct list_head *element, loff_t *pos)
487 {
488 	if (element->next == list)
489 		return NULL;
490 
491 	++(*pos);
492 	return element->next;
493 }
494 
495 static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
496 {
497 	/* acquire lock here ... Yes, we do need locking, I knowi, I know... */
498 
499 	return list_get_nth_element(&input_dev_list, pos);
500 }
501 
502 static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
503 {
504 	return list_get_next_element(&input_dev_list, v, pos);
505 }
506 
507 static void input_devices_seq_stop(struct seq_file *seq, void *v)
508 {
509 	/* release lock here */
510 }
511 
512 static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
513 				   unsigned long *bitmap, int max)
514 {
515 	int i;
516 
517 	for (i = NBITS(max) - 1; i > 0; i--)
518 		if (bitmap[i])
519 			break;
520 
521 	seq_printf(seq, "B: %s=", name);
522 	for (; i >= 0; i--)
523 		seq_printf(seq, "%lx%s", bitmap[i], i > 0 ? " " : "");
524 	seq_putc(seq, '\n');
525 }
526 
527 static int input_devices_seq_show(struct seq_file *seq, void *v)
528 {
529 	struct input_dev *dev = container_of(v, struct input_dev, node);
530 	const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
531 	struct input_handle *handle;
532 
533 	seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
534 		   dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
535 
536 	seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
537 	seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
538 	seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
539 	seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
540 	seq_printf(seq, "H: Handlers=");
541 
542 	list_for_each_entry(handle, &dev->h_list, d_node)
543 		seq_printf(seq, "%s ", handle->name);
544 	seq_putc(seq, '\n');
545 
546 	input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
547 	if (test_bit(EV_KEY, dev->evbit))
548 		input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
549 	if (test_bit(EV_REL, dev->evbit))
550 		input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
551 	if (test_bit(EV_ABS, dev->evbit))
552 		input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
553 	if (test_bit(EV_MSC, dev->evbit))
554 		input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
555 	if (test_bit(EV_LED, dev->evbit))
556 		input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
557 	if (test_bit(EV_SND, dev->evbit))
558 		input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
559 	if (test_bit(EV_FF, dev->evbit))
560 		input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
561 	if (test_bit(EV_SW, dev->evbit))
562 		input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);
563 
564 	seq_putc(seq, '\n');
565 
566 	kfree(path);
567 	return 0;
568 }
569 
570 static struct seq_operations input_devices_seq_ops = {
571 	.start	= input_devices_seq_start,
572 	.next	= input_devices_seq_next,
573 	.stop	= input_devices_seq_stop,
574 	.show	= input_devices_seq_show,
575 };
576 
577 static int input_proc_devices_open(struct inode *inode, struct file *file)
578 {
579 	return seq_open(file, &input_devices_seq_ops);
580 }
581 
582 static const struct file_operations input_devices_fileops = {
583 	.owner		= THIS_MODULE,
584 	.open		= input_proc_devices_open,
585 	.poll		= input_proc_devices_poll,
586 	.read		= seq_read,
587 	.llseek		= seq_lseek,
588 	.release	= seq_release,
589 };
590 
591 static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
592 {
593 	/* acquire lock here ... Yes, we do need locking, I knowi, I know... */
594 	seq->private = (void *)(unsigned long)*pos;
595 	return list_get_nth_element(&input_handler_list, pos);
596 }
597 
598 static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
599 {
600 	seq->private = (void *)(unsigned long)(*pos + 1);
601 	return list_get_next_element(&input_handler_list, v, pos);
602 }
603 
604 static void input_handlers_seq_stop(struct seq_file *seq, void *v)
605 {
606 	/* release lock here */
607 }
608 
609 static int input_handlers_seq_show(struct seq_file *seq, void *v)
610 {
611 	struct input_handler *handler = container_of(v, struct input_handler, node);
612 
613 	seq_printf(seq, "N: Number=%ld Name=%s",
614 		   (unsigned long)seq->private, handler->name);
615 	if (handler->fops)
616 		seq_printf(seq, " Minor=%d", handler->minor);
617 	seq_putc(seq, '\n');
618 
619 	return 0;
620 }
621 static struct seq_operations input_handlers_seq_ops = {
622 	.start	= input_handlers_seq_start,
623 	.next	= input_handlers_seq_next,
624 	.stop	= input_handlers_seq_stop,
625 	.show	= input_handlers_seq_show,
626 };
627 
628 static int input_proc_handlers_open(struct inode *inode, struct file *file)
629 {
630 	return seq_open(file, &input_handlers_seq_ops);
631 }
632 
633 static const struct file_operations input_handlers_fileops = {
634 	.owner		= THIS_MODULE,
635 	.open		= input_proc_handlers_open,
636 	.read		= seq_read,
637 	.llseek		= seq_lseek,
638 	.release	= seq_release,
639 };
640 
641 static int __init input_proc_init(void)
642 {
643 	struct proc_dir_entry *entry;
644 
645 	proc_bus_input_dir = proc_mkdir("input", proc_bus);
646 	if (!proc_bus_input_dir)
647 		return -ENOMEM;
648 
649 	proc_bus_input_dir->owner = THIS_MODULE;
650 
651 	entry = create_proc_entry("devices", 0, proc_bus_input_dir);
652 	if (!entry)
653 		goto fail1;
654 
655 	entry->owner = THIS_MODULE;
656 	entry->proc_fops = &input_devices_fileops;
657 
658 	entry = create_proc_entry("handlers", 0, proc_bus_input_dir);
659 	if (!entry)
660 		goto fail2;
661 
662 	entry->owner = THIS_MODULE;
663 	entry->proc_fops = &input_handlers_fileops;
664 
665 	return 0;
666 
667  fail2:	remove_proc_entry("devices", proc_bus_input_dir);
668  fail1: remove_proc_entry("input", proc_bus);
669 	return -ENOMEM;
670 }
671 
672 static void input_proc_exit(void)
673 {
674 	remove_proc_entry("devices", proc_bus_input_dir);
675 	remove_proc_entry("handlers", proc_bus_input_dir);
676 	remove_proc_entry("input", proc_bus);
677 }
678 
679 #else /* !CONFIG_PROC_FS */
680 static inline void input_wakeup_procfs_readers(void) { }
681 static inline int input_proc_init(void) { return 0; }
682 static inline void input_proc_exit(void) { }
683 #endif
684 
685 #define INPUT_DEV_STRING_ATTR_SHOW(name)				\
686 static ssize_t input_dev_show_##name(struct device *dev,		\
687 				     struct device_attribute *attr,	\
688 				     char *buf)				\
689 {									\
690 	struct input_dev *input_dev = to_input_dev(dev);		\
691 									\
692 	return scnprintf(buf, PAGE_SIZE, "%s\n",			\
693 			 input_dev->name ? input_dev->name : "");	\
694 }									\
695 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
696 
697 INPUT_DEV_STRING_ATTR_SHOW(name);
698 INPUT_DEV_STRING_ATTR_SHOW(phys);
699 INPUT_DEV_STRING_ATTR_SHOW(uniq);
700 
701 static int input_print_modalias_bits(char *buf, int size,
702 				     char name, unsigned long *bm,
703 				     unsigned int min_bit, unsigned int max_bit)
704 {
705 	int len = 0, i;
706 
707 	len += snprintf(buf, max(size, 0), "%c", name);
708 	for (i = min_bit; i < max_bit; i++)
709 		if (bm[LONG(i)] & BIT(i))
710 			len += snprintf(buf + len, max(size - len, 0), "%X,", i);
711 	return len;
712 }
713 
714 static int input_print_modalias(char *buf, int size, struct input_dev *id,
715 				int add_cr)
716 {
717 	int len;
718 
719 	len = snprintf(buf, max(size, 0),
720 		       "input:b%04Xv%04Xp%04Xe%04X-",
721 		       id->id.bustype, id->id.vendor,
722 		       id->id.product, id->id.version);
723 
724 	len += input_print_modalias_bits(buf + len, size - len,
725 				'e', id->evbit, 0, EV_MAX);
726 	len += input_print_modalias_bits(buf + len, size - len,
727 				'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
728 	len += input_print_modalias_bits(buf + len, size - len,
729 				'r', id->relbit, 0, REL_MAX);
730 	len += input_print_modalias_bits(buf + len, size - len,
731 				'a', id->absbit, 0, ABS_MAX);
732 	len += input_print_modalias_bits(buf + len, size - len,
733 				'm', id->mscbit, 0, MSC_MAX);
734 	len += input_print_modalias_bits(buf + len, size - len,
735 				'l', id->ledbit, 0, LED_MAX);
736 	len += input_print_modalias_bits(buf + len, size - len,
737 				's', id->sndbit, 0, SND_MAX);
738 	len += input_print_modalias_bits(buf + len, size - len,
739 				'f', id->ffbit, 0, FF_MAX);
740 	len += input_print_modalias_bits(buf + len, size - len,
741 				'w', id->swbit, 0, SW_MAX);
742 
743 	if (add_cr)
744 		len += snprintf(buf + len, max(size - len, 0), "\n");
745 
746 	return len;
747 }
748 
749 static ssize_t input_dev_show_modalias(struct device *dev,
750 				       struct device_attribute *attr,
751 				       char *buf)
752 {
753 	struct input_dev *id = to_input_dev(dev);
754 	ssize_t len;
755 
756 	len = input_print_modalias(buf, PAGE_SIZE, id, 1);
757 
758 	return min_t(int, len, PAGE_SIZE);
759 }
760 static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
761 
762 static struct attribute *input_dev_attrs[] = {
763 	&dev_attr_name.attr,
764 	&dev_attr_phys.attr,
765 	&dev_attr_uniq.attr,
766 	&dev_attr_modalias.attr,
767 	NULL
768 };
769 
770 static struct attribute_group input_dev_attr_group = {
771 	.attrs	= input_dev_attrs,
772 };
773 
774 #define INPUT_DEV_ID_ATTR(name)						\
775 static ssize_t input_dev_show_id_##name(struct device *dev,		\
776 					struct device_attribute *attr,	\
777 					char *buf)			\
778 {									\
779 	struct input_dev *input_dev = to_input_dev(dev);		\
780 	return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name);	\
781 }									\
782 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
783 
784 INPUT_DEV_ID_ATTR(bustype);
785 INPUT_DEV_ID_ATTR(vendor);
786 INPUT_DEV_ID_ATTR(product);
787 INPUT_DEV_ID_ATTR(version);
788 
789 static struct attribute *input_dev_id_attrs[] = {
790 	&dev_attr_bustype.attr,
791 	&dev_attr_vendor.attr,
792 	&dev_attr_product.attr,
793 	&dev_attr_version.attr,
794 	NULL
795 };
796 
797 static struct attribute_group input_dev_id_attr_group = {
798 	.name	= "id",
799 	.attrs	= input_dev_id_attrs,
800 };
801 
802 static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
803 			      int max, int add_cr)
804 {
805 	int i;
806 	int len = 0;
807 
808 	for (i = NBITS(max) - 1; i > 0; i--)
809 		if (bitmap[i])
810 			break;
811 
812 	for (; i >= 0; i--)
813 		len += snprintf(buf + len, max(buf_size - len, 0),
814 				"%lx%s", bitmap[i], i > 0 ? " " : "");
815 
816 	if (add_cr)
817 		len += snprintf(buf + len, max(buf_size - len, 0), "\n");
818 
819 	return len;
820 }
821 
822 #define INPUT_DEV_CAP_ATTR(ev, bm)					\
823 static ssize_t input_dev_show_cap_##bm(struct device *dev,		\
824 				       struct device_attribute *attr,	\
825 				       char *buf)			\
826 {									\
827 	struct input_dev *input_dev = to_input_dev(dev);		\
828 	int len = input_print_bitmap(buf, PAGE_SIZE,			\
829 				     input_dev->bm##bit, ev##_MAX, 1);	\
830 	return min_t(int, len, PAGE_SIZE);				\
831 }									\
832 static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
833 
834 INPUT_DEV_CAP_ATTR(EV, ev);
835 INPUT_DEV_CAP_ATTR(KEY, key);
836 INPUT_DEV_CAP_ATTR(REL, rel);
837 INPUT_DEV_CAP_ATTR(ABS, abs);
838 INPUT_DEV_CAP_ATTR(MSC, msc);
839 INPUT_DEV_CAP_ATTR(LED, led);
840 INPUT_DEV_CAP_ATTR(SND, snd);
841 INPUT_DEV_CAP_ATTR(FF, ff);
842 INPUT_DEV_CAP_ATTR(SW, sw);
843 
844 static struct attribute *input_dev_caps_attrs[] = {
845 	&dev_attr_ev.attr,
846 	&dev_attr_key.attr,
847 	&dev_attr_rel.attr,
848 	&dev_attr_abs.attr,
849 	&dev_attr_msc.attr,
850 	&dev_attr_led.attr,
851 	&dev_attr_snd.attr,
852 	&dev_attr_ff.attr,
853 	&dev_attr_sw.attr,
854 	NULL
855 };
856 
857 static struct attribute_group input_dev_caps_attr_group = {
858 	.name	= "capabilities",
859 	.attrs	= input_dev_caps_attrs,
860 };
861 
862 static struct attribute_group *input_dev_attr_groups[] = {
863 	&input_dev_attr_group,
864 	&input_dev_id_attr_group,
865 	&input_dev_caps_attr_group,
866 	NULL
867 };
868 
869 static void input_dev_release(struct device *device)
870 {
871 	struct input_dev *dev = to_input_dev(device);
872 
873 	input_ff_destroy(dev);
874 	kfree(dev);
875 
876 	module_put(THIS_MODULE);
877 }
878 
879 /*
880  * Input uevent interface - loading event handlers based on
881  * device bitfields.
882  */
883 static int input_add_uevent_bm_var(char **envp, int num_envp, int *cur_index,
884 				   char *buffer, int buffer_size, int *cur_len,
885 				   const char *name, unsigned long *bitmap, int max)
886 {
887 	if (*cur_index >= num_envp - 1)
888 		return -ENOMEM;
889 
890 	envp[*cur_index] = buffer + *cur_len;
891 
892 	*cur_len += snprintf(buffer + *cur_len, max(buffer_size - *cur_len, 0), name);
893 	if (*cur_len >= buffer_size)
894 		return -ENOMEM;
895 
896 	*cur_len += input_print_bitmap(buffer + *cur_len,
897 					max(buffer_size - *cur_len, 0),
898 					bitmap, max, 0) + 1;
899 	if (*cur_len > buffer_size)
900 		return -ENOMEM;
901 
902 	(*cur_index)++;
903 	return 0;
904 }
905 
906 static int input_add_uevent_modalias_var(char **envp, int num_envp, int *cur_index,
907 					 char *buffer, int buffer_size, int *cur_len,
908 					 struct input_dev *dev)
909 {
910 	if (*cur_index >= num_envp - 1)
911 		return -ENOMEM;
912 
913 	envp[*cur_index] = buffer + *cur_len;
914 
915 	*cur_len += snprintf(buffer + *cur_len, max(buffer_size - *cur_len, 0),
916 			     "MODALIAS=");
917 	if (*cur_len >= buffer_size)
918 		return -ENOMEM;
919 
920 	*cur_len += input_print_modalias(buffer + *cur_len,
921 					 max(buffer_size - *cur_len, 0),
922 					 dev, 0) + 1;
923 	if (*cur_len > buffer_size)
924 		return -ENOMEM;
925 
926 	(*cur_index)++;
927 	return 0;
928 }
929 
930 #define INPUT_ADD_HOTPLUG_VAR(fmt, val...)				\
931 	do {								\
932 		int err = add_uevent_var(envp, num_envp, &i,		\
933 					buffer, buffer_size, &len,	\
934 					fmt, val);			\
935 		if (err)						\
936 			return err;					\
937 	} while (0)
938 
939 #define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max)				\
940 	do {								\
941 		int err = input_add_uevent_bm_var(envp, num_envp, &i,	\
942 					buffer, buffer_size, &len,	\
943 					name, bm, max);			\
944 		if (err)						\
945 			return err;					\
946 	} while (0)
947 
948 #define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev)				\
949 	do {								\
950 		int err = input_add_uevent_modalias_var(envp,		\
951 					num_envp, &i,			\
952 					buffer, buffer_size, &len,	\
953 					dev);				\
954 		if (err)						\
955 			return err;					\
956 	} while (0)
957 
958 static int input_dev_uevent(struct device *device, char **envp,
959 			    int num_envp, char *buffer, int buffer_size)
960 {
961 	struct input_dev *dev = to_input_dev(device);
962 	int i = 0;
963 	int len = 0;
964 
965 	INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
966 				dev->id.bustype, dev->id.vendor,
967 				dev->id.product, dev->id.version);
968 	if (dev->name)
969 		INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
970 	if (dev->phys)
971 		INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
972 	if (dev->uniq)
973 		INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
974 
975 	INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
976 	if (test_bit(EV_KEY, dev->evbit))
977 		INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
978 	if (test_bit(EV_REL, dev->evbit))
979 		INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
980 	if (test_bit(EV_ABS, dev->evbit))
981 		INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
982 	if (test_bit(EV_MSC, dev->evbit))
983 		INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
984 	if (test_bit(EV_LED, dev->evbit))
985 		INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
986 	if (test_bit(EV_SND, dev->evbit))
987 		INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
988 	if (test_bit(EV_FF, dev->evbit))
989 		INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
990 	if (test_bit(EV_SW, dev->evbit))
991 		INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
992 
993 	INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
994 
995 	envp[i] = NULL;
996 	return 0;
997 }
998 
999 static struct device_type input_dev_type = {
1000 	.groups		= input_dev_attr_groups,
1001 	.release	= input_dev_release,
1002 	.uevent		= input_dev_uevent,
1003 };
1004 
1005 struct class input_class = {
1006 	.name		= "input",
1007 };
1008 EXPORT_SYMBOL_GPL(input_class);
1009 
1010 /**
1011  * input_allocate_device - allocate memory for new input device
1012  *
1013  * Returns prepared struct input_dev or NULL.
1014  *
1015  * NOTE: Use input_free_device() to free devices that have not been
1016  * registered; input_unregister_device() should be used for already
1017  * registered devices.
1018  */
1019 struct input_dev *input_allocate_device(void)
1020 {
1021 	struct input_dev *dev;
1022 
1023 	dev = kzalloc(sizeof(struct input_dev), GFP_KERNEL);
1024 	if (dev) {
1025 		dev->dev.type = &input_dev_type;
1026 		dev->dev.class = &input_class;
1027 		device_initialize(&dev->dev);
1028 		mutex_init(&dev->mutex);
1029 		INIT_LIST_HEAD(&dev->h_list);
1030 		INIT_LIST_HEAD(&dev->node);
1031 
1032 		__module_get(THIS_MODULE);
1033 	}
1034 
1035 	return dev;
1036 }
1037 EXPORT_SYMBOL(input_allocate_device);
1038 
1039 /**
1040  * input_free_device - free memory occupied by input_dev structure
1041  * @dev: input device to free
1042  *
1043  * This function should only be used if input_register_device()
1044  * was not called yet or if it failed. Once device was registered
1045  * use input_unregister_device() and memory will be freed once last
1046  * refrence to the device is dropped.
1047  *
1048  * Device should be allocated by input_allocate_device().
1049  *
1050  * NOTE: If there are references to the input device then memory
1051  * will not be freed until last reference is dropped.
1052  */
1053 void input_free_device(struct input_dev *dev)
1054 {
1055 	if (dev)
1056 		input_put_device(dev);
1057 }
1058 EXPORT_SYMBOL(input_free_device);
1059 
1060 /**
1061  * input_set_capability - mark device as capable of a certain event
1062  * @dev: device that is capable of emitting or accepting event
1063  * @type: type of the event (EV_KEY, EV_REL, etc...)
1064  * @code: event code
1065  *
1066  * In addition to setting up corresponding bit in appropriate capability
1067  * bitmap the function also adjusts dev->evbit.
1068  */
1069 void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
1070 {
1071 	switch (type) {
1072 	case EV_KEY:
1073 		__set_bit(code, dev->keybit);
1074 		break;
1075 
1076 	case EV_REL:
1077 		__set_bit(code, dev->relbit);
1078 		break;
1079 
1080 	case EV_ABS:
1081 		__set_bit(code, dev->absbit);
1082 		break;
1083 
1084 	case EV_MSC:
1085 		__set_bit(code, dev->mscbit);
1086 		break;
1087 
1088 	case EV_SW:
1089 		__set_bit(code, dev->swbit);
1090 		break;
1091 
1092 	case EV_LED:
1093 		__set_bit(code, dev->ledbit);
1094 		break;
1095 
1096 	case EV_SND:
1097 		__set_bit(code, dev->sndbit);
1098 		break;
1099 
1100 	case EV_FF:
1101 		__set_bit(code, dev->ffbit);
1102 		break;
1103 
1104 	default:
1105 		printk(KERN_ERR
1106 			"input_set_capability: unknown type %u (code %u)\n",
1107 			type, code);
1108 		dump_stack();
1109 		return;
1110 	}
1111 
1112 	__set_bit(type, dev->evbit);
1113 }
1114 EXPORT_SYMBOL(input_set_capability);
1115 
1116 int input_register_device(struct input_dev *dev)
1117 {
1118 	static atomic_t input_no = ATOMIC_INIT(0);
1119 	struct input_handler *handler;
1120 	const char *path;
1121 	int error;
1122 
1123 	set_bit(EV_SYN, dev->evbit);
1124 
1125 	/*
1126 	 * If delay and period are pre-set by the driver, then autorepeating
1127 	 * is handled by the driver itself and we don't do it in input.c.
1128 	 */
1129 
1130 	init_timer(&dev->timer);
1131 	if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD]) {
1132 		dev->timer.data = (long) dev;
1133 		dev->timer.function = input_repeat_key;
1134 		dev->rep[REP_DELAY] = 250;
1135 		dev->rep[REP_PERIOD] = 33;
1136 	}
1137 
1138 	if (!dev->getkeycode)
1139 		dev->getkeycode = input_default_getkeycode;
1140 
1141 	if (!dev->setkeycode)
1142 		dev->setkeycode = input_default_setkeycode;
1143 
1144 	list_add_tail(&dev->node, &input_dev_list);
1145 
1146 	snprintf(dev->dev.bus_id, sizeof(dev->dev.bus_id),
1147 		 "input%ld", (unsigned long) atomic_inc_return(&input_no) - 1);
1148 
1149 	if (dev->cdev.dev)
1150 		dev->dev.parent = dev->cdev.dev;
1151 
1152 	error = device_add(&dev->dev);
1153 	if (error)
1154 		return error;
1155 
1156 	path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1157 	printk(KERN_INFO "input: %s as %s\n",
1158 		dev->name ? dev->name : "Unspecified device", path ? path : "N/A");
1159 	kfree(path);
1160 
1161 	list_for_each_entry(handler, &input_handler_list, node)
1162 		input_attach_handler(dev, handler);
1163 
1164 	input_wakeup_procfs_readers();
1165 
1166 	return 0;
1167 }
1168 EXPORT_SYMBOL(input_register_device);
1169 
1170 void input_unregister_device(struct input_dev *dev)
1171 {
1172 	struct input_handle *handle, *next;
1173 	int code;
1174 
1175 	for (code = 0; code <= KEY_MAX; code++)
1176 		if (test_bit(code, dev->key))
1177 			input_report_key(dev, code, 0);
1178 	input_sync(dev);
1179 
1180 	del_timer_sync(&dev->timer);
1181 
1182 	list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
1183 		handle->handler->disconnect(handle);
1184 	WARN_ON(!list_empty(&dev->h_list));
1185 
1186 	list_del_init(&dev->node);
1187 
1188 	device_unregister(&dev->dev);
1189 
1190 	input_wakeup_procfs_readers();
1191 }
1192 EXPORT_SYMBOL(input_unregister_device);
1193 
1194 int input_register_handler(struct input_handler *handler)
1195 {
1196 	struct input_dev *dev;
1197 
1198 	INIT_LIST_HEAD(&handler->h_list);
1199 
1200 	if (handler->fops != NULL) {
1201 		if (input_table[handler->minor >> 5])
1202 			return -EBUSY;
1203 
1204 		input_table[handler->minor >> 5] = handler;
1205 	}
1206 
1207 	list_add_tail(&handler->node, &input_handler_list);
1208 
1209 	list_for_each_entry(dev, &input_dev_list, node)
1210 		input_attach_handler(dev, handler);
1211 
1212 	input_wakeup_procfs_readers();
1213 	return 0;
1214 }
1215 EXPORT_SYMBOL(input_register_handler);
1216 
1217 void input_unregister_handler(struct input_handler *handler)
1218 {
1219 	struct input_handle *handle, *next;
1220 
1221 	list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
1222 		handler->disconnect(handle);
1223 	WARN_ON(!list_empty(&handler->h_list));
1224 
1225 	list_del_init(&handler->node);
1226 
1227 	if (handler->fops != NULL)
1228 		input_table[handler->minor >> 5] = NULL;
1229 
1230 	input_wakeup_procfs_readers();
1231 }
1232 EXPORT_SYMBOL(input_unregister_handler);
1233 
1234 int input_register_handle(struct input_handle *handle)
1235 {
1236 	struct input_handler *handler = handle->handler;
1237 
1238 	list_add_tail(&handle->d_node, &handle->dev->h_list);
1239 	list_add_tail(&handle->h_node, &handler->h_list);
1240 
1241 	if (handler->start)
1242 		handler->start(handle);
1243 
1244 	return 0;
1245 }
1246 EXPORT_SYMBOL(input_register_handle);
1247 
1248 void input_unregister_handle(struct input_handle *handle)
1249 {
1250 	list_del_init(&handle->h_node);
1251 	list_del_init(&handle->d_node);
1252 }
1253 EXPORT_SYMBOL(input_unregister_handle);
1254 
1255 static int input_open_file(struct inode *inode, struct file *file)
1256 {
1257 	struct input_handler *handler = input_table[iminor(inode) >> 5];
1258 	const struct file_operations *old_fops, *new_fops = NULL;
1259 	int err;
1260 
1261 	/* No load-on-demand here? */
1262 	if (!handler || !(new_fops = fops_get(handler->fops)))
1263 		return -ENODEV;
1264 
1265 	/*
1266 	 * That's _really_ odd. Usually NULL ->open means "nothing special",
1267 	 * not "no device". Oh, well...
1268 	 */
1269 	if (!new_fops->open) {
1270 		fops_put(new_fops);
1271 		return -ENODEV;
1272 	}
1273 	old_fops = file->f_op;
1274 	file->f_op = new_fops;
1275 
1276 	err = new_fops->open(inode, file);
1277 
1278 	if (err) {
1279 		fops_put(file->f_op);
1280 		file->f_op = fops_get(old_fops);
1281 	}
1282 	fops_put(old_fops);
1283 	return err;
1284 }
1285 
1286 static const struct file_operations input_fops = {
1287 	.owner = THIS_MODULE,
1288 	.open = input_open_file,
1289 };
1290 
1291 static int __init input_init(void)
1292 {
1293 	int err;
1294 
1295 	err = class_register(&input_class);
1296 	if (err) {
1297 		printk(KERN_ERR "input: unable to register input_dev class\n");
1298 		return err;
1299 	}
1300 
1301 	err = input_proc_init();
1302 	if (err)
1303 		goto fail1;
1304 
1305 	err = register_chrdev(INPUT_MAJOR, "input", &input_fops);
1306 	if (err) {
1307 		printk(KERN_ERR "input: unable to register char major %d", INPUT_MAJOR);
1308 		goto fail2;
1309 	}
1310 
1311 	return 0;
1312 
1313  fail2:	input_proc_exit();
1314  fail1:	class_unregister(&input_class);
1315 	return err;
1316 }
1317 
1318 static void __exit input_exit(void)
1319 {
1320 	input_proc_exit();
1321 	unregister_chrdev(INPUT_MAJOR, "input");
1322 	class_unregister(&input_class);
1323 }
1324 
1325 subsys_initcall(input_init);
1326 module_exit(input_exit);
1327