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Input: remove BKL, fix input_open_file() locking
[deliverable/linux.git] / drivers / input / input.c
1 /*
2 * The input core
3 *
4 * Copyright (c) 1999-2002 Vojtech Pavlik
5 */
6
7 /*
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License version 2 as published by
10 * the Free Software Foundation.
11 */
12
13 #include <linux/init.h>
14 #include <linux/types.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/sched.h>
21 #include <linux/seq_file.h>
22 #include <linux/poll.h>
23 #include <linux/device.h>
24 #include <linux/mutex.h>
25 #include <linux/rcupdate.h>
26 #include <linux/smp_lock.h>
27 #include "input-compat.h"
28
29 MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
30 MODULE_DESCRIPTION("Input core");
31 MODULE_LICENSE("GPL");
32
33 #define INPUT_DEVICES 256
34
35 /*
36 * EV_ABS events which should not be cached are listed here.
37 */
38 static unsigned int input_abs_bypass_init_data[] __initdata = {
39 ABS_MT_TOUCH_MAJOR,
40 ABS_MT_TOUCH_MINOR,
41 ABS_MT_WIDTH_MAJOR,
42 ABS_MT_WIDTH_MINOR,
43 ABS_MT_ORIENTATION,
44 ABS_MT_POSITION_X,
45 ABS_MT_POSITION_Y,
46 ABS_MT_TOOL_TYPE,
47 ABS_MT_BLOB_ID,
48 ABS_MT_TRACKING_ID,
49 ABS_MT_PRESSURE,
50 0
51 };
52 static unsigned long input_abs_bypass[BITS_TO_LONGS(ABS_CNT)];
53
54 static LIST_HEAD(input_dev_list);
55 static LIST_HEAD(input_handler_list);
56
57 /*
58 * input_mutex protects access to both input_dev_list and input_handler_list.
59 * This also causes input_[un]register_device and input_[un]register_handler
60 * be mutually exclusive which simplifies locking in drivers implementing
61 * input handlers.
62 */
63 static DEFINE_MUTEX(input_mutex);
64
65 static struct input_handler *input_table[8];
66
67 static inline int is_event_supported(unsigned int code,
68 unsigned long *bm, unsigned int max)
69 {
70 return code <= max && test_bit(code, bm);
71 }
72
73 static int input_defuzz_abs_event(int value, int old_val, int fuzz)
74 {
75 if (fuzz) {
76 if (value > old_val - fuzz / 2 && value < old_val + fuzz / 2)
77 return old_val;
78
79 if (value > old_val - fuzz && value < old_val + fuzz)
80 return (old_val * 3 + value) / 4;
81
82 if (value > old_val - fuzz * 2 && value < old_val + fuzz * 2)
83 return (old_val + value) / 2;
84 }
85
86 return value;
87 }
88
89 /*
90 * Pass event first through all filters and then, if event has not been
91 * filtered out, through all open handles. This function is called with
92 * dev->event_lock held and interrupts disabled.
93 */
94 static void input_pass_event(struct input_dev *dev,
95 unsigned int type, unsigned int code, int value)
96 {
97 struct input_handler *handler;
98 struct input_handle *handle;
99
100 rcu_read_lock();
101
102 handle = rcu_dereference(dev->grab);
103 if (handle)
104 handle->handler->event(handle, type, code, value);
105 else {
106 bool filtered = false;
107
108 list_for_each_entry_rcu(handle, &dev->h_list, d_node) {
109 if (!handle->open)
110 continue;
111
112 handler = handle->handler;
113 if (!handler->filter) {
114 if (filtered)
115 break;
116
117 handler->event(handle, type, code, value);
118
119 } else if (handler->filter(handle, type, code, value))
120 filtered = true;
121 }
122 }
123
124 rcu_read_unlock();
125 }
126
127 /*
128 * Generate software autorepeat event. Note that we take
129 * dev->event_lock here to avoid racing with input_event
130 * which may cause keys get "stuck".
131 */
132 static void input_repeat_key(unsigned long data)
133 {
134 struct input_dev *dev = (void *) data;
135 unsigned long flags;
136
137 spin_lock_irqsave(&dev->event_lock, flags);
138
139 if (test_bit(dev->repeat_key, dev->key) &&
140 is_event_supported(dev->repeat_key, dev->keybit, KEY_MAX)) {
141
142 input_pass_event(dev, EV_KEY, dev->repeat_key, 2);
143
144 if (dev->sync) {
145 /*
146 * Only send SYN_REPORT if we are not in a middle
147 * of driver parsing a new hardware packet.
148 * Otherwise assume that the driver will send
149 * SYN_REPORT once it's done.
150 */
151 input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
152 }
153
154 if (dev->rep[REP_PERIOD])
155 mod_timer(&dev->timer, jiffies +
156 msecs_to_jiffies(dev->rep[REP_PERIOD]));
157 }
158
159 spin_unlock_irqrestore(&dev->event_lock, flags);
160 }
161
162 static void input_start_autorepeat(struct input_dev *dev, int code)
163 {
164 if (test_bit(EV_REP, dev->evbit) &&
165 dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] &&
166 dev->timer.data) {
167 dev->repeat_key = code;
168 mod_timer(&dev->timer,
169 jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
170 }
171 }
172
173 static void input_stop_autorepeat(struct input_dev *dev)
174 {
175 del_timer(&dev->timer);
176 }
177
178 #define INPUT_IGNORE_EVENT 0
179 #define INPUT_PASS_TO_HANDLERS 1
180 #define INPUT_PASS_TO_DEVICE 2
181 #define INPUT_PASS_TO_ALL (INPUT_PASS_TO_HANDLERS | INPUT_PASS_TO_DEVICE)
182
183 static void input_handle_event(struct input_dev *dev,
184 unsigned int type, unsigned int code, int value)
185 {
186 int disposition = INPUT_IGNORE_EVENT;
187
188 switch (type) {
189
190 case EV_SYN:
191 switch (code) {
192 case SYN_CONFIG:
193 disposition = INPUT_PASS_TO_ALL;
194 break;
195
196 case SYN_REPORT:
197 if (!dev->sync) {
198 dev->sync = 1;
199 disposition = INPUT_PASS_TO_HANDLERS;
200 }
201 break;
202 case SYN_MT_REPORT:
203 dev->sync = 0;
204 disposition = INPUT_PASS_TO_HANDLERS;
205 break;
206 }
207 break;
208
209 case EV_KEY:
210 if (is_event_supported(code, dev->keybit, KEY_MAX) &&
211 !!test_bit(code, dev->key) != value) {
212
213 if (value != 2) {
214 __change_bit(code, dev->key);
215 if (value)
216 input_start_autorepeat(dev, code);
217 else
218 input_stop_autorepeat(dev);
219 }
220
221 disposition = INPUT_PASS_TO_HANDLERS;
222 }
223 break;
224
225 case EV_SW:
226 if (is_event_supported(code, dev->swbit, SW_MAX) &&
227 !!test_bit(code, dev->sw) != value) {
228
229 __change_bit(code, dev->sw);
230 disposition = INPUT_PASS_TO_HANDLERS;
231 }
232 break;
233
234 case EV_ABS:
235 if (is_event_supported(code, dev->absbit, ABS_MAX)) {
236
237 if (test_bit(code, input_abs_bypass)) {
238 disposition = INPUT_PASS_TO_HANDLERS;
239 break;
240 }
241
242 value = input_defuzz_abs_event(value,
243 dev->abs[code], dev->absfuzz[code]);
244
245 if (dev->abs[code] != value) {
246 dev->abs[code] = value;
247 disposition = INPUT_PASS_TO_HANDLERS;
248 }
249 }
250 break;
251
252 case EV_REL:
253 if (is_event_supported(code, dev->relbit, REL_MAX) && value)
254 disposition = INPUT_PASS_TO_HANDLERS;
255
256 break;
257
258 case EV_MSC:
259 if (is_event_supported(code, dev->mscbit, MSC_MAX))
260 disposition = INPUT_PASS_TO_ALL;
261
262 break;
263
264 case EV_LED:
265 if (is_event_supported(code, dev->ledbit, LED_MAX) &&
266 !!test_bit(code, dev->led) != value) {
267
268 __change_bit(code, dev->led);
269 disposition = INPUT_PASS_TO_ALL;
270 }
271 break;
272
273 case EV_SND:
274 if (is_event_supported(code, dev->sndbit, SND_MAX)) {
275
276 if (!!test_bit(code, dev->snd) != !!value)
277 __change_bit(code, dev->snd);
278 disposition = INPUT_PASS_TO_ALL;
279 }
280 break;
281
282 case EV_REP:
283 if (code <= REP_MAX && value >= 0 && dev->rep[code] != value) {
284 dev->rep[code] = value;
285 disposition = INPUT_PASS_TO_ALL;
286 }
287 break;
288
289 case EV_FF:
290 if (value >= 0)
291 disposition = INPUT_PASS_TO_ALL;
292 break;
293
294 case EV_PWR:
295 disposition = INPUT_PASS_TO_ALL;
296 break;
297 }
298
299 if (disposition != INPUT_IGNORE_EVENT && type != EV_SYN)
300 dev->sync = 0;
301
302 if ((disposition & INPUT_PASS_TO_DEVICE) && dev->event)
303 dev->event(dev, type, code, value);
304
305 if (disposition & INPUT_PASS_TO_HANDLERS)
306 input_pass_event(dev, type, code, value);
307 }
308
309 /**
310 * input_event() - report new input event
311 * @dev: device that generated the event
312 * @type: type of the event
313 * @code: event code
314 * @value: value of the event
315 *
316 * This function should be used by drivers implementing various input
317 * devices to report input events. See also input_inject_event().
318 *
319 * NOTE: input_event() may be safely used right after input device was
320 * allocated with input_allocate_device(), even before it is registered
321 * with input_register_device(), but the event will not reach any of the
322 * input handlers. Such early invocation of input_event() may be used
323 * to 'seed' initial state of a switch or initial position of absolute
324 * axis, etc.
325 */
326 void input_event(struct input_dev *dev,
327 unsigned int type, unsigned int code, int value)
328 {
329 unsigned long flags;
330
331 if (is_event_supported(type, dev->evbit, EV_MAX)) {
332
333 spin_lock_irqsave(&dev->event_lock, flags);
334 add_input_randomness(type, code, value);
335 input_handle_event(dev, type, code, value);
336 spin_unlock_irqrestore(&dev->event_lock, flags);
337 }
338 }
339 EXPORT_SYMBOL(input_event);
340
341 /**
342 * input_inject_event() - send input event from input handler
343 * @handle: input handle to send event through
344 * @type: type of the event
345 * @code: event code
346 * @value: value of the event
347 *
348 * Similar to input_event() but will ignore event if device is
349 * "grabbed" and handle injecting event is not the one that owns
350 * the device.
351 */
352 void input_inject_event(struct input_handle *handle,
353 unsigned int type, unsigned int code, int value)
354 {
355 struct input_dev *dev = handle->dev;
356 struct input_handle *grab;
357 unsigned long flags;
358
359 if (is_event_supported(type, dev->evbit, EV_MAX)) {
360 spin_lock_irqsave(&dev->event_lock, flags);
361
362 rcu_read_lock();
363 grab = rcu_dereference(dev->grab);
364 if (!grab || grab == handle)
365 input_handle_event(dev, type, code, value);
366 rcu_read_unlock();
367
368 spin_unlock_irqrestore(&dev->event_lock, flags);
369 }
370 }
371 EXPORT_SYMBOL(input_inject_event);
372
373 /**
374 * input_grab_device - grabs device for exclusive use
375 * @handle: input handle that wants to own the device
376 *
377 * When a device is grabbed by an input handle all events generated by
378 * the device are delivered only to this handle. Also events injected
379 * by other input handles are ignored while device is grabbed.
380 */
381 int input_grab_device(struct input_handle *handle)
382 {
383 struct input_dev *dev = handle->dev;
384 int retval;
385
386 retval = mutex_lock_interruptible(&dev->mutex);
387 if (retval)
388 return retval;
389
390 if (dev->grab) {
391 retval = -EBUSY;
392 goto out;
393 }
394
395 rcu_assign_pointer(dev->grab, handle);
396 synchronize_rcu();
397
398 out:
399 mutex_unlock(&dev->mutex);
400 return retval;
401 }
402 EXPORT_SYMBOL(input_grab_device);
403
404 static void __input_release_device(struct input_handle *handle)
405 {
406 struct input_dev *dev = handle->dev;
407
408 if (dev->grab == handle) {
409 rcu_assign_pointer(dev->grab, NULL);
410 /* Make sure input_pass_event() notices that grab is gone */
411 synchronize_rcu();
412
413 list_for_each_entry(handle, &dev->h_list, d_node)
414 if (handle->open && handle->handler->start)
415 handle->handler->start(handle);
416 }
417 }
418
419 /**
420 * input_release_device - release previously grabbed device
421 * @handle: input handle that owns the device
422 *
423 * Releases previously grabbed device so that other input handles can
424 * start receiving input events. Upon release all handlers attached
425 * to the device have their start() method called so they have a change
426 * to synchronize device state with the rest of the system.
427 */
428 void input_release_device(struct input_handle *handle)
429 {
430 struct input_dev *dev = handle->dev;
431
432 mutex_lock(&dev->mutex);
433 __input_release_device(handle);
434 mutex_unlock(&dev->mutex);
435 }
436 EXPORT_SYMBOL(input_release_device);
437
438 /**
439 * input_open_device - open input device
440 * @handle: handle through which device is being accessed
441 *
442 * This function should be called by input handlers when they
443 * want to start receive events from given input device.
444 */
445 int input_open_device(struct input_handle *handle)
446 {
447 struct input_dev *dev = handle->dev;
448 int retval;
449
450 retval = mutex_lock_interruptible(&dev->mutex);
451 if (retval)
452 return retval;
453
454 if (dev->going_away) {
455 retval = -ENODEV;
456 goto out;
457 }
458
459 handle->open++;
460
461 if (!dev->users++ && dev->open)
462 retval = dev->open(dev);
463
464 if (retval) {
465 dev->users--;
466 if (!--handle->open) {
467 /*
468 * Make sure we are not delivering any more events
469 * through this handle
470 */
471 synchronize_rcu();
472 }
473 }
474
475 out:
476 mutex_unlock(&dev->mutex);
477 return retval;
478 }
479 EXPORT_SYMBOL(input_open_device);
480
481 int input_flush_device(struct input_handle *handle, struct file *file)
482 {
483 struct input_dev *dev = handle->dev;
484 int retval;
485
486 retval = mutex_lock_interruptible(&dev->mutex);
487 if (retval)
488 return retval;
489
490 if (dev->flush)
491 retval = dev->flush(dev, file);
492
493 mutex_unlock(&dev->mutex);
494 return retval;
495 }
496 EXPORT_SYMBOL(input_flush_device);
497
498 /**
499 * input_close_device - close input device
500 * @handle: handle through which device is being accessed
501 *
502 * This function should be called by input handlers when they
503 * want to stop receive events from given input device.
504 */
505 void input_close_device(struct input_handle *handle)
506 {
507 struct input_dev *dev = handle->dev;
508
509 mutex_lock(&dev->mutex);
510
511 __input_release_device(handle);
512
513 if (!--dev->users && dev->close)
514 dev->close(dev);
515
516 if (!--handle->open) {
517 /*
518 * synchronize_rcu() makes sure that input_pass_event()
519 * completed and that no more input events are delivered
520 * through this handle
521 */
522 synchronize_rcu();
523 }
524
525 mutex_unlock(&dev->mutex);
526 }
527 EXPORT_SYMBOL(input_close_device);
528
529 /*
530 * Prepare device for unregistering
531 */
532 static void input_disconnect_device(struct input_dev *dev)
533 {
534 struct input_handle *handle;
535 int code;
536
537 /*
538 * Mark device as going away. Note that we take dev->mutex here
539 * not to protect access to dev->going_away but rather to ensure
540 * that there are no threads in the middle of input_open_device()
541 */
542 mutex_lock(&dev->mutex);
543 dev->going_away = true;
544 mutex_unlock(&dev->mutex);
545
546 spin_lock_irq(&dev->event_lock);
547
548 /*
549 * Simulate keyup events for all pressed keys so that handlers
550 * are not left with "stuck" keys. The driver may continue
551 * generate events even after we done here but they will not
552 * reach any handlers.
553 */
554 if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
555 for (code = 0; code <= KEY_MAX; code++) {
556 if (is_event_supported(code, dev->keybit, KEY_MAX) &&
557 __test_and_clear_bit(code, dev->key)) {
558 input_pass_event(dev, EV_KEY, code, 0);
559 }
560 }
561 input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
562 }
563
564 list_for_each_entry(handle, &dev->h_list, d_node)
565 handle->open = 0;
566
567 spin_unlock_irq(&dev->event_lock);
568 }
569
570 static int input_fetch_keycode(struct input_dev *dev, int scancode)
571 {
572 switch (dev->keycodesize) {
573 case 1:
574 return ((u8 *)dev->keycode)[scancode];
575
576 case 2:
577 return ((u16 *)dev->keycode)[scancode];
578
579 default:
580 return ((u32 *)dev->keycode)[scancode];
581 }
582 }
583
584 static int input_default_getkeycode(struct input_dev *dev,
585 unsigned int scancode,
586 unsigned int *keycode)
587 {
588 if (!dev->keycodesize)
589 return -EINVAL;
590
591 if (scancode >= dev->keycodemax)
592 return -EINVAL;
593
594 *keycode = input_fetch_keycode(dev, scancode);
595
596 return 0;
597 }
598
599 static int input_default_setkeycode(struct input_dev *dev,
600 unsigned int scancode,
601 unsigned int keycode)
602 {
603 int old_keycode;
604 int i;
605
606 if (scancode >= dev->keycodemax)
607 return -EINVAL;
608
609 if (!dev->keycodesize)
610 return -EINVAL;
611
612 if (dev->keycodesize < sizeof(keycode) && (keycode >> (dev->keycodesize * 8)))
613 return -EINVAL;
614
615 switch (dev->keycodesize) {
616 case 1: {
617 u8 *k = (u8 *)dev->keycode;
618 old_keycode = k[scancode];
619 k[scancode] = keycode;
620 break;
621 }
622 case 2: {
623 u16 *k = (u16 *)dev->keycode;
624 old_keycode = k[scancode];
625 k[scancode] = keycode;
626 break;
627 }
628 default: {
629 u32 *k = (u32 *)dev->keycode;
630 old_keycode = k[scancode];
631 k[scancode] = keycode;
632 break;
633 }
634 }
635
636 __clear_bit(old_keycode, dev->keybit);
637 __set_bit(keycode, dev->keybit);
638
639 for (i = 0; i < dev->keycodemax; i++) {
640 if (input_fetch_keycode(dev, i) == old_keycode) {
641 __set_bit(old_keycode, dev->keybit);
642 break; /* Setting the bit twice is useless, so break */
643 }
644 }
645
646 return 0;
647 }
648
649 /**
650 * input_get_keycode - retrieve keycode currently mapped to a given scancode
651 * @dev: input device which keymap is being queried
652 * @scancode: scancode (or its equivalent for device in question) for which
653 * keycode is needed
654 * @keycode: result
655 *
656 * This function should be called by anyone interested in retrieving current
657 * keymap. Presently keyboard and evdev handlers use it.
658 */
659 int input_get_keycode(struct input_dev *dev,
660 unsigned int scancode, unsigned int *keycode)
661 {
662 return dev->getkeycode(dev, scancode, keycode);
663 }
664 EXPORT_SYMBOL(input_get_keycode);
665
666 /**
667 * input_get_keycode - assign new keycode to a given scancode
668 * @dev: input device which keymap is being updated
669 * @scancode: scancode (or its equivalent for device in question)
670 * @keycode: new keycode to be assigned to the scancode
671 *
672 * This function should be called by anyone needing to update current
673 * keymap. Presently keyboard and evdev handlers use it.
674 */
675 int input_set_keycode(struct input_dev *dev,
676 unsigned int scancode, unsigned int keycode)
677 {
678 unsigned long flags;
679 int old_keycode;
680 int retval;
681
682 if (keycode > KEY_MAX)
683 return -EINVAL;
684
685 spin_lock_irqsave(&dev->event_lock, flags);
686
687 retval = dev->getkeycode(dev, scancode, &old_keycode);
688 if (retval)
689 goto out;
690
691 retval = dev->setkeycode(dev, scancode, keycode);
692 if (retval)
693 goto out;
694
695 /* Make sure KEY_RESERVED did not get enabled. */
696 __clear_bit(KEY_RESERVED, dev->keybit);
697
698 /*
699 * Simulate keyup event if keycode is not present
700 * in the keymap anymore
701 */
702 if (test_bit(EV_KEY, dev->evbit) &&
703 !is_event_supported(old_keycode, dev->keybit, KEY_MAX) &&
704 __test_and_clear_bit(old_keycode, dev->key)) {
705
706 input_pass_event(dev, EV_KEY, old_keycode, 0);
707 if (dev->sync)
708 input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
709 }
710
711 out:
712 spin_unlock_irqrestore(&dev->event_lock, flags);
713
714 return retval;
715 }
716 EXPORT_SYMBOL(input_set_keycode);
717
718 #define MATCH_BIT(bit, max) \
719 for (i = 0; i < BITS_TO_LONGS(max); i++) \
720 if ((id->bit[i] & dev->bit[i]) != id->bit[i]) \
721 break; \
722 if (i != BITS_TO_LONGS(max)) \
723 continue;
724
725 static const struct input_device_id *input_match_device(struct input_handler *handler,
726 struct input_dev *dev)
727 {
728 const struct input_device_id *id;
729 int i;
730
731 for (id = handler->id_table; id->flags || id->driver_info; id++) {
732
733 if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
734 if (id->bustype != dev->id.bustype)
735 continue;
736
737 if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
738 if (id->vendor != dev->id.vendor)
739 continue;
740
741 if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
742 if (id->product != dev->id.product)
743 continue;
744
745 if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
746 if (id->version != dev->id.version)
747 continue;
748
749 MATCH_BIT(evbit, EV_MAX);
750 MATCH_BIT(keybit, KEY_MAX);
751 MATCH_BIT(relbit, REL_MAX);
752 MATCH_BIT(absbit, ABS_MAX);
753 MATCH_BIT(mscbit, MSC_MAX);
754 MATCH_BIT(ledbit, LED_MAX);
755 MATCH_BIT(sndbit, SND_MAX);
756 MATCH_BIT(ffbit, FF_MAX);
757 MATCH_BIT(swbit, SW_MAX);
758
759 if (!handler->match || handler->match(handler, dev))
760 return id;
761 }
762
763 return NULL;
764 }
765
766 static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
767 {
768 const struct input_device_id *id;
769 int error;
770
771 id = input_match_device(handler, dev);
772 if (!id)
773 return -ENODEV;
774
775 error = handler->connect(handler, dev, id);
776 if (error && error != -ENODEV)
777 printk(KERN_ERR
778 "input: failed to attach handler %s to device %s, "
779 "error: %d\n",
780 handler->name, kobject_name(&dev->dev.kobj), error);
781
782 return error;
783 }
784
785 #ifdef CONFIG_COMPAT
786
787 static int input_bits_to_string(char *buf, int buf_size,
788 unsigned long bits, bool skip_empty)
789 {
790 int len = 0;
791
792 if (INPUT_COMPAT_TEST) {
793 u32 dword = bits >> 32;
794 if (dword || !skip_empty)
795 len += snprintf(buf, buf_size, "%x ", dword);
796
797 dword = bits & 0xffffffffUL;
798 if (dword || !skip_empty || len)
799 len += snprintf(buf + len, max(buf_size - len, 0),
800 "%x", dword);
801 } else {
802 if (bits || !skip_empty)
803 len += snprintf(buf, buf_size, "%lx", bits);
804 }
805
806 return len;
807 }
808
809 #else /* !CONFIG_COMPAT */
810
811 static int input_bits_to_string(char *buf, int buf_size,
812 unsigned long bits, bool skip_empty)
813 {
814 return bits || !skip_empty ?
815 snprintf(buf, buf_size, "%lx", bits) : 0;
816 }
817
818 #endif
819
820 #ifdef CONFIG_PROC_FS
821
822 static struct proc_dir_entry *proc_bus_input_dir;
823 static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
824 static int input_devices_state;
825
826 static inline void input_wakeup_procfs_readers(void)
827 {
828 input_devices_state++;
829 wake_up(&input_devices_poll_wait);
830 }
831
832 static unsigned int input_proc_devices_poll(struct file *file, poll_table *wait)
833 {
834 poll_wait(file, &input_devices_poll_wait, wait);
835 if (file->f_version != input_devices_state) {
836 file->f_version = input_devices_state;
837 return POLLIN | POLLRDNORM;
838 }
839
840 return 0;
841 }
842
843 union input_seq_state {
844 struct {
845 unsigned short pos;
846 bool mutex_acquired;
847 };
848 void *p;
849 };
850
851 static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
852 {
853 union input_seq_state *state = (union input_seq_state *)&seq->private;
854 int error;
855
856 /* We need to fit into seq->private pointer */
857 BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
858
859 error = mutex_lock_interruptible(&input_mutex);
860 if (error) {
861 state->mutex_acquired = false;
862 return ERR_PTR(error);
863 }
864
865 state->mutex_acquired = true;
866
867 return seq_list_start(&input_dev_list, *pos);
868 }
869
870 static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
871 {
872 return seq_list_next(v, &input_dev_list, pos);
873 }
874
875 static void input_seq_stop(struct seq_file *seq, void *v)
876 {
877 union input_seq_state *state = (union input_seq_state *)&seq->private;
878
879 if (state->mutex_acquired)
880 mutex_unlock(&input_mutex);
881 }
882
883 static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
884 unsigned long *bitmap, int max)
885 {
886 int i;
887 bool skip_empty = true;
888 char buf[18];
889
890 seq_printf(seq, "B: %s=", name);
891
892 for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
893 if (input_bits_to_string(buf, sizeof(buf),
894 bitmap[i], skip_empty)) {
895 skip_empty = false;
896 seq_printf(seq, "%s%s", buf, i > 0 ? " " : "");
897 }
898 }
899
900 /*
901 * If no output was produced print a single 0.
902 */
903 if (skip_empty)
904 seq_puts(seq, "0");
905
906 seq_putc(seq, '\n');
907 }
908
909 static int input_devices_seq_show(struct seq_file *seq, void *v)
910 {
911 struct input_dev *dev = container_of(v, struct input_dev, node);
912 const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
913 struct input_handle *handle;
914
915 seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
916 dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
917
918 seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
919 seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
920 seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
921 seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
922 seq_printf(seq, "H: Handlers=");
923
924 list_for_each_entry(handle, &dev->h_list, d_node)
925 seq_printf(seq, "%s ", handle->name);
926 seq_putc(seq, '\n');
927
928 input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
929 if (test_bit(EV_KEY, dev->evbit))
930 input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
931 if (test_bit(EV_REL, dev->evbit))
932 input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
933 if (test_bit(EV_ABS, dev->evbit))
934 input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
935 if (test_bit(EV_MSC, dev->evbit))
936 input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
937 if (test_bit(EV_LED, dev->evbit))
938 input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
939 if (test_bit(EV_SND, dev->evbit))
940 input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
941 if (test_bit(EV_FF, dev->evbit))
942 input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
943 if (test_bit(EV_SW, dev->evbit))
944 input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);
945
946 seq_putc(seq, '\n');
947
948 kfree(path);
949 return 0;
950 }
951
952 static const struct seq_operations input_devices_seq_ops = {
953 .start = input_devices_seq_start,
954 .next = input_devices_seq_next,
955 .stop = input_seq_stop,
956 .show = input_devices_seq_show,
957 };
958
959 static int input_proc_devices_open(struct inode *inode, struct file *file)
960 {
961 return seq_open(file, &input_devices_seq_ops);
962 }
963
964 static const struct file_operations input_devices_fileops = {
965 .owner = THIS_MODULE,
966 .open = input_proc_devices_open,
967 .poll = input_proc_devices_poll,
968 .read = seq_read,
969 .llseek = seq_lseek,
970 .release = seq_release,
971 };
972
973 static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
974 {
975 union input_seq_state *state = (union input_seq_state *)&seq->private;
976 int error;
977
978 /* We need to fit into seq->private pointer */
979 BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
980
981 error = mutex_lock_interruptible(&input_mutex);
982 if (error) {
983 state->mutex_acquired = false;
984 return ERR_PTR(error);
985 }
986
987 state->mutex_acquired = true;
988 state->pos = *pos;
989
990 return seq_list_start(&input_handler_list, *pos);
991 }
992
993 static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
994 {
995 union input_seq_state *state = (union input_seq_state *)&seq->private;
996
997 state->pos = *pos + 1;
998 return seq_list_next(v, &input_handler_list, pos);
999 }
1000
1001 static int input_handlers_seq_show(struct seq_file *seq, void *v)
1002 {
1003 struct input_handler *handler = container_of(v, struct input_handler, node);
1004 union input_seq_state *state = (union input_seq_state *)&seq->private;
1005
1006 seq_printf(seq, "N: Number=%u Name=%s", state->pos, handler->name);
1007 if (handler->filter)
1008 seq_puts(seq, " (filter)");
1009 if (handler->fops)
1010 seq_printf(seq, " Minor=%d", handler->minor);
1011 seq_putc(seq, '\n');
1012
1013 return 0;
1014 }
1015
1016 static const struct seq_operations input_handlers_seq_ops = {
1017 .start = input_handlers_seq_start,
1018 .next = input_handlers_seq_next,
1019 .stop = input_seq_stop,
1020 .show = input_handlers_seq_show,
1021 };
1022
1023 static int input_proc_handlers_open(struct inode *inode, struct file *file)
1024 {
1025 return seq_open(file, &input_handlers_seq_ops);
1026 }
1027
1028 static const struct file_operations input_handlers_fileops = {
1029 .owner = THIS_MODULE,
1030 .open = input_proc_handlers_open,
1031 .read = seq_read,
1032 .llseek = seq_lseek,
1033 .release = seq_release,
1034 };
1035
1036 static int __init input_proc_init(void)
1037 {
1038 struct proc_dir_entry *entry;
1039
1040 proc_bus_input_dir = proc_mkdir("bus/input", NULL);
1041 if (!proc_bus_input_dir)
1042 return -ENOMEM;
1043
1044 entry = proc_create("devices", 0, proc_bus_input_dir,
1045 &input_devices_fileops);
1046 if (!entry)
1047 goto fail1;
1048
1049 entry = proc_create("handlers", 0, proc_bus_input_dir,
1050 &input_handlers_fileops);
1051 if (!entry)
1052 goto fail2;
1053
1054 return 0;
1055
1056 fail2: remove_proc_entry("devices", proc_bus_input_dir);
1057 fail1: remove_proc_entry("bus/input", NULL);
1058 return -ENOMEM;
1059 }
1060
1061 static void input_proc_exit(void)
1062 {
1063 remove_proc_entry("devices", proc_bus_input_dir);
1064 remove_proc_entry("handlers", proc_bus_input_dir);
1065 remove_proc_entry("bus/input", NULL);
1066 }
1067
1068 #else /* !CONFIG_PROC_FS */
1069 static inline void input_wakeup_procfs_readers(void) { }
1070 static inline int input_proc_init(void) { return 0; }
1071 static inline void input_proc_exit(void) { }
1072 #endif
1073
1074 #define INPUT_DEV_STRING_ATTR_SHOW(name) \
1075 static ssize_t input_dev_show_##name(struct device *dev, \
1076 struct device_attribute *attr, \
1077 char *buf) \
1078 { \
1079 struct input_dev *input_dev = to_input_dev(dev); \
1080 \
1081 return scnprintf(buf, PAGE_SIZE, "%s\n", \
1082 input_dev->name ? input_dev->name : ""); \
1083 } \
1084 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
1085
1086 INPUT_DEV_STRING_ATTR_SHOW(name);
1087 INPUT_DEV_STRING_ATTR_SHOW(phys);
1088 INPUT_DEV_STRING_ATTR_SHOW(uniq);
1089
1090 static int input_print_modalias_bits(char *buf, int size,
1091 char name, unsigned long *bm,
1092 unsigned int min_bit, unsigned int max_bit)
1093 {
1094 int len = 0, i;
1095
1096 len += snprintf(buf, max(size, 0), "%c", name);
1097 for (i = min_bit; i < max_bit; i++)
1098 if (bm[BIT_WORD(i)] & BIT_MASK(i))
1099 len += snprintf(buf + len, max(size - len, 0), "%X,", i);
1100 return len;
1101 }
1102
1103 static int input_print_modalias(char *buf, int size, struct input_dev *id,
1104 int add_cr)
1105 {
1106 int len;
1107
1108 len = snprintf(buf, max(size, 0),
1109 "input:b%04Xv%04Xp%04Xe%04X-",
1110 id->id.bustype, id->id.vendor,
1111 id->id.product, id->id.version);
1112
1113 len += input_print_modalias_bits(buf + len, size - len,
1114 'e', id->evbit, 0, EV_MAX);
1115 len += input_print_modalias_bits(buf + len, size - len,
1116 'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
1117 len += input_print_modalias_bits(buf + len, size - len,
1118 'r', id->relbit, 0, REL_MAX);
1119 len += input_print_modalias_bits(buf + len, size - len,
1120 'a', id->absbit, 0, ABS_MAX);
1121 len += input_print_modalias_bits(buf + len, size - len,
1122 'm', id->mscbit, 0, MSC_MAX);
1123 len += input_print_modalias_bits(buf + len, size - len,
1124 'l', id->ledbit, 0, LED_MAX);
1125 len += input_print_modalias_bits(buf + len, size - len,
1126 's', id->sndbit, 0, SND_MAX);
1127 len += input_print_modalias_bits(buf + len, size - len,
1128 'f', id->ffbit, 0, FF_MAX);
1129 len += input_print_modalias_bits(buf + len, size - len,
1130 'w', id->swbit, 0, SW_MAX);
1131
1132 if (add_cr)
1133 len += snprintf(buf + len, max(size - len, 0), "\n");
1134
1135 return len;
1136 }
1137
1138 static ssize_t input_dev_show_modalias(struct device *dev,
1139 struct device_attribute *attr,
1140 char *buf)
1141 {
1142 struct input_dev *id = to_input_dev(dev);
1143 ssize_t len;
1144
1145 len = input_print_modalias(buf, PAGE_SIZE, id, 1);
1146
1147 return min_t(int, len, PAGE_SIZE);
1148 }
1149 static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
1150
1151 static struct attribute *input_dev_attrs[] = {
1152 &dev_attr_name.attr,
1153 &dev_attr_phys.attr,
1154 &dev_attr_uniq.attr,
1155 &dev_attr_modalias.attr,
1156 NULL
1157 };
1158
1159 static struct attribute_group input_dev_attr_group = {
1160 .attrs = input_dev_attrs,
1161 };
1162
1163 #define INPUT_DEV_ID_ATTR(name) \
1164 static ssize_t input_dev_show_id_##name(struct device *dev, \
1165 struct device_attribute *attr, \
1166 char *buf) \
1167 { \
1168 struct input_dev *input_dev = to_input_dev(dev); \
1169 return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name); \
1170 } \
1171 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
1172
1173 INPUT_DEV_ID_ATTR(bustype);
1174 INPUT_DEV_ID_ATTR(vendor);
1175 INPUT_DEV_ID_ATTR(product);
1176 INPUT_DEV_ID_ATTR(version);
1177
1178 static struct attribute *input_dev_id_attrs[] = {
1179 &dev_attr_bustype.attr,
1180 &dev_attr_vendor.attr,
1181 &dev_attr_product.attr,
1182 &dev_attr_version.attr,
1183 NULL
1184 };
1185
1186 static struct attribute_group input_dev_id_attr_group = {
1187 .name = "id",
1188 .attrs = input_dev_id_attrs,
1189 };
1190
1191 static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1192 int max, int add_cr)
1193 {
1194 int i;
1195 int len = 0;
1196 bool skip_empty = true;
1197
1198 for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1199 len += input_bits_to_string(buf + len, max(buf_size - len, 0),
1200 bitmap[i], skip_empty);
1201 if (len) {
1202 skip_empty = false;
1203 if (i > 0)
1204 len += snprintf(buf + len, max(buf_size - len, 0), " ");
1205 }
1206 }
1207
1208 /*
1209 * If no output was produced print a single 0.
1210 */
1211 if (len == 0)
1212 len = snprintf(buf, buf_size, "%d", 0);
1213
1214 if (add_cr)
1215 len += snprintf(buf + len, max(buf_size - len, 0), "\n");
1216
1217 return len;
1218 }
1219
1220 #define INPUT_DEV_CAP_ATTR(ev, bm) \
1221 static ssize_t input_dev_show_cap_##bm(struct device *dev, \
1222 struct device_attribute *attr, \
1223 char *buf) \
1224 { \
1225 struct input_dev *input_dev = to_input_dev(dev); \
1226 int len = input_print_bitmap(buf, PAGE_SIZE, \
1227 input_dev->bm##bit, ev##_MAX, \
1228 true); \
1229 return min_t(int, len, PAGE_SIZE); \
1230 } \
1231 static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
1232
1233 INPUT_DEV_CAP_ATTR(EV, ev);
1234 INPUT_DEV_CAP_ATTR(KEY, key);
1235 INPUT_DEV_CAP_ATTR(REL, rel);
1236 INPUT_DEV_CAP_ATTR(ABS, abs);
1237 INPUT_DEV_CAP_ATTR(MSC, msc);
1238 INPUT_DEV_CAP_ATTR(LED, led);
1239 INPUT_DEV_CAP_ATTR(SND, snd);
1240 INPUT_DEV_CAP_ATTR(FF, ff);
1241 INPUT_DEV_CAP_ATTR(SW, sw);
1242
1243 static struct attribute *input_dev_caps_attrs[] = {
1244 &dev_attr_ev.attr,
1245 &dev_attr_key.attr,
1246 &dev_attr_rel.attr,
1247 &dev_attr_abs.attr,
1248 &dev_attr_msc.attr,
1249 &dev_attr_led.attr,
1250 &dev_attr_snd.attr,
1251 &dev_attr_ff.attr,
1252 &dev_attr_sw.attr,
1253 NULL
1254 };
1255
1256 static struct attribute_group input_dev_caps_attr_group = {
1257 .name = "capabilities",
1258 .attrs = input_dev_caps_attrs,
1259 };
1260
1261 static const struct attribute_group *input_dev_attr_groups[] = {
1262 &input_dev_attr_group,
1263 &input_dev_id_attr_group,
1264 &input_dev_caps_attr_group,
1265 NULL
1266 };
1267
1268 static void input_dev_release(struct device *device)
1269 {
1270 struct input_dev *dev = to_input_dev(device);
1271
1272 input_ff_destroy(dev);
1273 kfree(dev);
1274
1275 module_put(THIS_MODULE);
1276 }
1277
1278 /*
1279 * Input uevent interface - loading event handlers based on
1280 * device bitfields.
1281 */
1282 static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
1283 const char *name, unsigned long *bitmap, int max)
1284 {
1285 int len;
1286
1287 if (add_uevent_var(env, "%s=", name))
1288 return -ENOMEM;
1289
1290 len = input_print_bitmap(&env->buf[env->buflen - 1],
1291 sizeof(env->buf) - env->buflen,
1292 bitmap, max, false);
1293 if (len >= (sizeof(env->buf) - env->buflen))
1294 return -ENOMEM;
1295
1296 env->buflen += len;
1297 return 0;
1298 }
1299
1300 static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
1301 struct input_dev *dev)
1302 {
1303 int len;
1304
1305 if (add_uevent_var(env, "MODALIAS="))
1306 return -ENOMEM;
1307
1308 len = input_print_modalias(&env->buf[env->buflen - 1],
1309 sizeof(env->buf) - env->buflen,
1310 dev, 0);
1311 if (len >= (sizeof(env->buf) - env->buflen))
1312 return -ENOMEM;
1313
1314 env->buflen += len;
1315 return 0;
1316 }
1317
1318 #define INPUT_ADD_HOTPLUG_VAR(fmt, val...) \
1319 do { \
1320 int err = add_uevent_var(env, fmt, val); \
1321 if (err) \
1322 return err; \
1323 } while (0)
1324
1325 #define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max) \
1326 do { \
1327 int err = input_add_uevent_bm_var(env, name, bm, max); \
1328 if (err) \
1329 return err; \
1330 } while (0)
1331
1332 #define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev) \
1333 do { \
1334 int err = input_add_uevent_modalias_var(env, dev); \
1335 if (err) \
1336 return err; \
1337 } while (0)
1338
1339 static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
1340 {
1341 struct input_dev *dev = to_input_dev(device);
1342
1343 INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
1344 dev->id.bustype, dev->id.vendor,
1345 dev->id.product, dev->id.version);
1346 if (dev->name)
1347 INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
1348 if (dev->phys)
1349 INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
1350 if (dev->uniq)
1351 INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
1352
1353 INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
1354 if (test_bit(EV_KEY, dev->evbit))
1355 INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
1356 if (test_bit(EV_REL, dev->evbit))
1357 INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
1358 if (test_bit(EV_ABS, dev->evbit))
1359 INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
1360 if (test_bit(EV_MSC, dev->evbit))
1361 INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
1362 if (test_bit(EV_LED, dev->evbit))
1363 INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
1364 if (test_bit(EV_SND, dev->evbit))
1365 INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
1366 if (test_bit(EV_FF, dev->evbit))
1367 INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
1368 if (test_bit(EV_SW, dev->evbit))
1369 INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
1370
1371 INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
1372
1373 return 0;
1374 }
1375
1376 #define INPUT_DO_TOGGLE(dev, type, bits, on) \
1377 do { \
1378 int i; \
1379 bool active; \
1380 \
1381 if (!test_bit(EV_##type, dev->evbit)) \
1382 break; \
1383 \
1384 for (i = 0; i < type##_MAX; i++) { \
1385 if (!test_bit(i, dev->bits##bit)) \
1386 continue; \
1387 \
1388 active = test_bit(i, dev->bits); \
1389 if (!active && !on) \
1390 continue; \
1391 \
1392 dev->event(dev, EV_##type, i, on ? active : 0); \
1393 } \
1394 } while (0)
1395
1396 #ifdef CONFIG_PM
1397 static void input_dev_reset(struct input_dev *dev, bool activate)
1398 {
1399 if (!dev->event)
1400 return;
1401
1402 INPUT_DO_TOGGLE(dev, LED, led, activate);
1403 INPUT_DO_TOGGLE(dev, SND, snd, activate);
1404
1405 if (activate && test_bit(EV_REP, dev->evbit)) {
1406 dev->event(dev, EV_REP, REP_PERIOD, dev->rep[REP_PERIOD]);
1407 dev->event(dev, EV_REP, REP_DELAY, dev->rep[REP_DELAY]);
1408 }
1409 }
1410
1411 static int input_dev_suspend(struct device *dev)
1412 {
1413 struct input_dev *input_dev = to_input_dev(dev);
1414
1415 mutex_lock(&input_dev->mutex);
1416 input_dev_reset(input_dev, false);
1417 mutex_unlock(&input_dev->mutex);
1418
1419 return 0;
1420 }
1421
1422 static int input_dev_resume(struct device *dev)
1423 {
1424 struct input_dev *input_dev = to_input_dev(dev);
1425
1426 mutex_lock(&input_dev->mutex);
1427 input_dev_reset(input_dev, true);
1428 mutex_unlock(&input_dev->mutex);
1429
1430 return 0;
1431 }
1432
1433 static const struct dev_pm_ops input_dev_pm_ops = {
1434 .suspend = input_dev_suspend,
1435 .resume = input_dev_resume,
1436 .poweroff = input_dev_suspend,
1437 .restore = input_dev_resume,
1438 };
1439 #endif /* CONFIG_PM */
1440
1441 static struct device_type input_dev_type = {
1442 .groups = input_dev_attr_groups,
1443 .release = input_dev_release,
1444 .uevent = input_dev_uevent,
1445 #ifdef CONFIG_PM
1446 .pm = &input_dev_pm_ops,
1447 #endif
1448 };
1449
1450 static char *input_devnode(struct device *dev, mode_t *mode)
1451 {
1452 return kasprintf(GFP_KERNEL, "input/%s", dev_name(dev));
1453 }
1454
1455 struct class input_class = {
1456 .name = "input",
1457 .devnode = input_devnode,
1458 };
1459 EXPORT_SYMBOL_GPL(input_class);
1460
1461 /**
1462 * input_allocate_device - allocate memory for new input device
1463 *
1464 * Returns prepared struct input_dev or NULL.
1465 *
1466 * NOTE: Use input_free_device() to free devices that have not been
1467 * registered; input_unregister_device() should be used for already
1468 * registered devices.
1469 */
1470 struct input_dev *input_allocate_device(void)
1471 {
1472 struct input_dev *dev;
1473
1474 dev = kzalloc(sizeof(struct input_dev), GFP_KERNEL);
1475 if (dev) {
1476 dev->dev.type = &input_dev_type;
1477 dev->dev.class = &input_class;
1478 device_initialize(&dev->dev);
1479 mutex_init(&dev->mutex);
1480 spin_lock_init(&dev->event_lock);
1481 INIT_LIST_HEAD(&dev->h_list);
1482 INIT_LIST_HEAD(&dev->node);
1483
1484 __module_get(THIS_MODULE);
1485 }
1486
1487 return dev;
1488 }
1489 EXPORT_SYMBOL(input_allocate_device);
1490
1491 /**
1492 * input_free_device - free memory occupied by input_dev structure
1493 * @dev: input device to free
1494 *
1495 * This function should only be used if input_register_device()
1496 * was not called yet or if it failed. Once device was registered
1497 * use input_unregister_device() and memory will be freed once last
1498 * reference to the device is dropped.
1499 *
1500 * Device should be allocated by input_allocate_device().
1501 *
1502 * NOTE: If there are references to the input device then memory
1503 * will not be freed until last reference is dropped.
1504 */
1505 void input_free_device(struct input_dev *dev)
1506 {
1507 if (dev)
1508 input_put_device(dev);
1509 }
1510 EXPORT_SYMBOL(input_free_device);
1511
1512 /**
1513 * input_set_capability - mark device as capable of a certain event
1514 * @dev: device that is capable of emitting or accepting event
1515 * @type: type of the event (EV_KEY, EV_REL, etc...)
1516 * @code: event code
1517 *
1518 * In addition to setting up corresponding bit in appropriate capability
1519 * bitmap the function also adjusts dev->evbit.
1520 */
1521 void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
1522 {
1523 switch (type) {
1524 case EV_KEY:
1525 __set_bit(code, dev->keybit);
1526 break;
1527
1528 case EV_REL:
1529 __set_bit(code, dev->relbit);
1530 break;
1531
1532 case EV_ABS:
1533 __set_bit(code, dev->absbit);
1534 break;
1535
1536 case EV_MSC:
1537 __set_bit(code, dev->mscbit);
1538 break;
1539
1540 case EV_SW:
1541 __set_bit(code, dev->swbit);
1542 break;
1543
1544 case EV_LED:
1545 __set_bit(code, dev->ledbit);
1546 break;
1547
1548 case EV_SND:
1549 __set_bit(code, dev->sndbit);
1550 break;
1551
1552 case EV_FF:
1553 __set_bit(code, dev->ffbit);
1554 break;
1555
1556 case EV_PWR:
1557 /* do nothing */
1558 break;
1559
1560 default:
1561 printk(KERN_ERR
1562 "input_set_capability: unknown type %u (code %u)\n",
1563 type, code);
1564 dump_stack();
1565 return;
1566 }
1567
1568 __set_bit(type, dev->evbit);
1569 }
1570 EXPORT_SYMBOL(input_set_capability);
1571
1572 #define INPUT_CLEANSE_BITMASK(dev, type, bits) \
1573 do { \
1574 if (!test_bit(EV_##type, dev->evbit)) \
1575 memset(dev->bits##bit, 0, \
1576 sizeof(dev->bits##bit)); \
1577 } while (0)
1578
1579 static void input_cleanse_bitmasks(struct input_dev *dev)
1580 {
1581 INPUT_CLEANSE_BITMASK(dev, KEY, key);
1582 INPUT_CLEANSE_BITMASK(dev, REL, rel);
1583 INPUT_CLEANSE_BITMASK(dev, ABS, abs);
1584 INPUT_CLEANSE_BITMASK(dev, MSC, msc);
1585 INPUT_CLEANSE_BITMASK(dev, LED, led);
1586 INPUT_CLEANSE_BITMASK(dev, SND, snd);
1587 INPUT_CLEANSE_BITMASK(dev, FF, ff);
1588 INPUT_CLEANSE_BITMASK(dev, SW, sw);
1589 }
1590
1591 /**
1592 * input_register_device - register device with input core
1593 * @dev: device to be registered
1594 *
1595 * This function registers device with input core. The device must be
1596 * allocated with input_allocate_device() and all it's capabilities
1597 * set up before registering.
1598 * If function fails the device must be freed with input_free_device().
1599 * Once device has been successfully registered it can be unregistered
1600 * with input_unregister_device(); input_free_device() should not be
1601 * called in this case.
1602 */
1603 int input_register_device(struct input_dev *dev)
1604 {
1605 static atomic_t input_no = ATOMIC_INIT(0);
1606 struct input_handler *handler;
1607 const char *path;
1608 int error;
1609
1610 /* Every input device generates EV_SYN/SYN_REPORT events. */
1611 __set_bit(EV_SYN, dev->evbit);
1612
1613 /* KEY_RESERVED is not supposed to be transmitted to userspace. */
1614 __clear_bit(KEY_RESERVED, dev->keybit);
1615
1616 /* Make sure that bitmasks not mentioned in dev->evbit are clean. */
1617 input_cleanse_bitmasks(dev);
1618
1619 /*
1620 * If delay and period are pre-set by the driver, then autorepeating
1621 * is handled by the driver itself and we don't do it in input.c.
1622 */
1623 init_timer(&dev->timer);
1624 if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD]) {
1625 dev->timer.data = (long) dev;
1626 dev->timer.function = input_repeat_key;
1627 dev->rep[REP_DELAY] = 250;
1628 dev->rep[REP_PERIOD] = 33;
1629 }
1630
1631 if (!dev->getkeycode)
1632 dev->getkeycode = input_default_getkeycode;
1633
1634 if (!dev->setkeycode)
1635 dev->setkeycode = input_default_setkeycode;
1636
1637 dev_set_name(&dev->dev, "input%ld",
1638 (unsigned long) atomic_inc_return(&input_no) - 1);
1639
1640 error = device_add(&dev->dev);
1641 if (error)
1642 return error;
1643
1644 path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1645 printk(KERN_INFO "input: %s as %s\n",
1646 dev->name ? dev->name : "Unspecified device", path ? path : "N/A");
1647 kfree(path);
1648
1649 error = mutex_lock_interruptible(&input_mutex);
1650 if (error) {
1651 device_del(&dev->dev);
1652 return error;
1653 }
1654
1655 list_add_tail(&dev->node, &input_dev_list);
1656
1657 list_for_each_entry(handler, &input_handler_list, node)
1658 input_attach_handler(dev, handler);
1659
1660 input_wakeup_procfs_readers();
1661
1662 mutex_unlock(&input_mutex);
1663
1664 return 0;
1665 }
1666 EXPORT_SYMBOL(input_register_device);
1667
1668 /**
1669 * input_unregister_device - unregister previously registered device
1670 * @dev: device to be unregistered
1671 *
1672 * This function unregisters an input device. Once device is unregistered
1673 * the caller should not try to access it as it may get freed at any moment.
1674 */
1675 void input_unregister_device(struct input_dev *dev)
1676 {
1677 struct input_handle *handle, *next;
1678
1679 input_disconnect_device(dev);
1680
1681 mutex_lock(&input_mutex);
1682
1683 list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
1684 handle->handler->disconnect(handle);
1685 WARN_ON(!list_empty(&dev->h_list));
1686
1687 del_timer_sync(&dev->timer);
1688 list_del_init(&dev->node);
1689
1690 input_wakeup_procfs_readers();
1691
1692 mutex_unlock(&input_mutex);
1693
1694 device_unregister(&dev->dev);
1695 }
1696 EXPORT_SYMBOL(input_unregister_device);
1697
1698 /**
1699 * input_register_handler - register a new input handler
1700 * @handler: handler to be registered
1701 *
1702 * This function registers a new input handler (interface) for input
1703 * devices in the system and attaches it to all input devices that
1704 * are compatible with the handler.
1705 */
1706 int input_register_handler(struct input_handler *handler)
1707 {
1708 struct input_dev *dev;
1709 int retval;
1710
1711 retval = mutex_lock_interruptible(&input_mutex);
1712 if (retval)
1713 return retval;
1714
1715 INIT_LIST_HEAD(&handler->h_list);
1716
1717 if (handler->fops != NULL) {
1718 if (input_table[handler->minor >> 5]) {
1719 retval = -EBUSY;
1720 goto out;
1721 }
1722 input_table[handler->minor >> 5] = handler;
1723 }
1724
1725 list_add_tail(&handler->node, &input_handler_list);
1726
1727 list_for_each_entry(dev, &input_dev_list, node)
1728 input_attach_handler(dev, handler);
1729
1730 input_wakeup_procfs_readers();
1731
1732 out:
1733 mutex_unlock(&input_mutex);
1734 return retval;
1735 }
1736 EXPORT_SYMBOL(input_register_handler);
1737
1738 /**
1739 * input_unregister_handler - unregisters an input handler
1740 * @handler: handler to be unregistered
1741 *
1742 * This function disconnects a handler from its input devices and
1743 * removes it from lists of known handlers.
1744 */
1745 void input_unregister_handler(struct input_handler *handler)
1746 {
1747 struct input_handle *handle, *next;
1748
1749 mutex_lock(&input_mutex);
1750
1751 list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
1752 handler->disconnect(handle);
1753 WARN_ON(!list_empty(&handler->h_list));
1754
1755 list_del_init(&handler->node);
1756
1757 if (handler->fops != NULL)
1758 input_table[handler->minor >> 5] = NULL;
1759
1760 input_wakeup_procfs_readers();
1761
1762 mutex_unlock(&input_mutex);
1763 }
1764 EXPORT_SYMBOL(input_unregister_handler);
1765
1766 /**
1767 * input_handler_for_each_handle - handle iterator
1768 * @handler: input handler to iterate
1769 * @data: data for the callback
1770 * @fn: function to be called for each handle
1771 *
1772 * Iterate over @bus's list of devices, and call @fn for each, passing
1773 * it @data and stop when @fn returns a non-zero value. The function is
1774 * using RCU to traverse the list and therefore may be usind in atonic
1775 * contexts. The @fn callback is invoked from RCU critical section and
1776 * thus must not sleep.
1777 */
1778 int input_handler_for_each_handle(struct input_handler *handler, void *data,
1779 int (*fn)(struct input_handle *, void *))
1780 {
1781 struct input_handle *handle;
1782 int retval = 0;
1783
1784 rcu_read_lock();
1785
1786 list_for_each_entry_rcu(handle, &handler->h_list, h_node) {
1787 retval = fn(handle, data);
1788 if (retval)
1789 break;
1790 }
1791
1792 rcu_read_unlock();
1793
1794 return retval;
1795 }
1796 EXPORT_SYMBOL(input_handler_for_each_handle);
1797
1798 /**
1799 * input_register_handle - register a new input handle
1800 * @handle: handle to register
1801 *
1802 * This function puts a new input handle onto device's
1803 * and handler's lists so that events can flow through
1804 * it once it is opened using input_open_device().
1805 *
1806 * This function is supposed to be called from handler's
1807 * connect() method.
1808 */
1809 int input_register_handle(struct input_handle *handle)
1810 {
1811 struct input_handler *handler = handle->handler;
1812 struct input_dev *dev = handle->dev;
1813 int error;
1814
1815 /*
1816 * We take dev->mutex here to prevent race with
1817 * input_release_device().
1818 */
1819 error = mutex_lock_interruptible(&dev->mutex);
1820 if (error)
1821 return error;
1822
1823 /*
1824 * Filters go to the head of the list, normal handlers
1825 * to the tail.
1826 */
1827 if (handler->filter)
1828 list_add_rcu(&handle->d_node, &dev->h_list);
1829 else
1830 list_add_tail_rcu(&handle->d_node, &dev->h_list);
1831
1832 mutex_unlock(&dev->mutex);
1833
1834 /*
1835 * Since we are supposed to be called from ->connect()
1836 * which is mutually exclusive with ->disconnect()
1837 * we can't be racing with input_unregister_handle()
1838 * and so separate lock is not needed here.
1839 */
1840 list_add_tail_rcu(&handle->h_node, &handler->h_list);
1841
1842 if (handler->start)
1843 handler->start(handle);
1844
1845 return 0;
1846 }
1847 EXPORT_SYMBOL(input_register_handle);
1848
1849 /**
1850 * input_unregister_handle - unregister an input handle
1851 * @handle: handle to unregister
1852 *
1853 * This function removes input handle from device's
1854 * and handler's lists.
1855 *
1856 * This function is supposed to be called from handler's
1857 * disconnect() method.
1858 */
1859 void input_unregister_handle(struct input_handle *handle)
1860 {
1861 struct input_dev *dev = handle->dev;
1862
1863 list_del_rcu(&handle->h_node);
1864
1865 /*
1866 * Take dev->mutex to prevent race with input_release_device().
1867 */
1868 mutex_lock(&dev->mutex);
1869 list_del_rcu(&handle->d_node);
1870 mutex_unlock(&dev->mutex);
1871
1872 synchronize_rcu();
1873 }
1874 EXPORT_SYMBOL(input_unregister_handle);
1875
1876 static int input_open_file(struct inode *inode, struct file *file)
1877 {
1878 struct input_handler *handler;
1879 const struct file_operations *old_fops, *new_fops = NULL;
1880 int err;
1881
1882 err = mutex_lock_interruptible(&input_mutex);
1883 if (err)
1884 return err;
1885
1886 /* No load-on-demand here? */
1887 handler = input_table[iminor(inode) >> 5];
1888 if (handler)
1889 new_fops = fops_get(handler->fops);
1890
1891 mutex_unlock(&input_mutex);
1892
1893 /*
1894 * That's _really_ odd. Usually NULL ->open means "nothing special",
1895 * not "no device". Oh, well...
1896 */
1897 if (!new_fops || !new_fops->open) {
1898 fops_put(new_fops);
1899 err = -ENODEV;
1900 goto out;
1901 }
1902
1903 old_fops = file->f_op;
1904 file->f_op = new_fops;
1905
1906 err = new_fops->open(inode, file);
1907 if (err) {
1908 fops_put(file->f_op);
1909 file->f_op = fops_get(old_fops);
1910 }
1911 fops_put(old_fops);
1912 out:
1913 return err;
1914 }
1915
1916 static const struct file_operations input_fops = {
1917 .owner = THIS_MODULE,
1918 .open = input_open_file,
1919 };
1920
1921 static void __init input_init_abs_bypass(void)
1922 {
1923 const unsigned int *p;
1924
1925 for (p = input_abs_bypass_init_data; *p; p++)
1926 input_abs_bypass[BIT_WORD(*p)] |= BIT_MASK(*p);
1927 }
1928
1929 static int __init input_init(void)
1930 {
1931 int err;
1932
1933 input_init_abs_bypass();
1934
1935 err = class_register(&input_class);
1936 if (err) {
1937 printk(KERN_ERR "input: unable to register input_dev class\n");
1938 return err;
1939 }
1940
1941 err = input_proc_init();
1942 if (err)
1943 goto fail1;
1944
1945 err = register_chrdev(INPUT_MAJOR, "input", &input_fops);
1946 if (err) {
1947 printk(KERN_ERR "input: unable to register char major %d", INPUT_MAJOR);
1948 goto fail2;
1949 }
1950
1951 return 0;
1952
1953 fail2: input_proc_exit();
1954 fail1: class_unregister(&input_class);
1955 return err;
1956 }
1957
1958 static void __exit input_exit(void)
1959 {
1960 input_proc_exit();
1961 unregister_chrdev(INPUT_MAJOR, "input");
1962 class_unregister(&input_class);
1963 }
1964
1965 subsys_initcall(input_init);
1966 module_exit(input_exit);
Linux kernel - Deliverables
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