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fs: use kmem_cache_zalloc instead
[pv_ops_mirror.git] / drivers / input / input.c
blob2f2b020cd6294109da6e757e2968c12bca97aaef
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/poll.h>
21 #include <linux/device.h>
22 #include <linux/mutex.h>
23 #include <linux/rcupdate.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 /*
35 * input_mutex protects access to both input_dev_list and input_handler_list.
36 * This also causes input_[un]register_device and input_[un]register_handler
37 * be mutually exclusive which simplifies locking in drivers implementing
38 * input handlers.
39 */
40 static DEFINE_MUTEX(input_mutex);
41
42 static struct input_handler *input_table[8];
43
44 static inline int is_event_supported(unsigned int code,
45 unsigned long *bm, unsigned int max)
46 {
47 return code <= max && test_bit(code, bm);
48 }
49
50 static int input_defuzz_abs_event(int value, int old_val, int fuzz)
51 {
52 if (fuzz) {
53 if (value > old_val - fuzz / 2 && value < old_val + fuzz / 2)
54 return old_val;
55
56 if (value > old_val - fuzz && value < old_val + fuzz)
57 return (old_val * 3 + value) / 4;
58
59 if (value > old_val - fuzz * 2 && value < old_val + fuzz * 2)
60 return (old_val + value) / 2;
61 }
62
63 return value;
64 }
65
66 /*
67 * Pass event through all open handles. This function is called with
68 * dev->event_lock held and interrupts disabled.
69 */
70 static void input_pass_event(struct input_dev *dev,
71 unsigned int type, unsigned int code, int value)
72 {
73 struct input_handle *handle;
74
75 rcu_read_lock();
76
77 handle = rcu_dereference(dev->grab);
78 if (handle)
79 handle->handler->event(handle, type, code, value);
80 else
81 list_for_each_entry_rcu(handle, &dev->h_list, d_node)
82 if (handle->open)
83 handle->handler->event(handle,
84 type, code, value);
85 rcu_read_unlock();
86 }
87
88 /*
89 * Generate software autorepeat event. Note that we take
90 * dev->event_lock here to avoid racing with input_event
91 * which may cause keys get "stuck".
92 */
93 static void input_repeat_key(unsigned long data)
94 {
95 struct input_dev *dev = (void *) data;
96 unsigned long flags;
97
98 spin_lock_irqsave(&dev->event_lock, flags);
99
100 if (test_bit(dev->repeat_key, dev->key) &&
101 is_event_supported(dev->repeat_key, dev->keybit, KEY_MAX)) {
102
103 input_pass_event(dev, EV_KEY, dev->repeat_key, 2);
104
105 if (dev->sync) {
106 /*
107 * Only send SYN_REPORT if we are not in a middle
108 * of driver parsing a new hardware packet.
109 * Otherwise assume that the driver will send
110 * SYN_REPORT once it's done.
111 */
112 input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
113 }
114
115 if (dev->rep[REP_PERIOD])
116 mod_timer(&dev->timer, jiffies +
117 msecs_to_jiffies(dev->rep[REP_PERIOD]));
118 }
119
120 spin_unlock_irqrestore(&dev->event_lock, flags);
121 }
122
123 static void input_start_autorepeat(struct input_dev *dev, int code)
124 {
125 if (test_bit(EV_REP, dev->evbit) &&
126 dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] &&
127 dev->timer.data) {
128 dev->repeat_key = code;
129 mod_timer(&dev->timer,
130 jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
131 }
132 }
133
134 #define INPUT_IGNORE_EVENT 0
135 #define INPUT_PASS_TO_HANDLERS 1
136 #define INPUT_PASS_TO_DEVICE 2
137 #define INPUT_PASS_TO_ALL (INPUT_PASS_TO_HANDLERS | INPUT_PASS_TO_DEVICE)
138
139 static void input_handle_event(struct input_dev *dev,
140 unsigned int type, unsigned int code, int value)
141 {
142 int disposition = INPUT_IGNORE_EVENT;
143
144 switch (type) {
145
146 case EV_SYN:
147 switch (code) {
148 case SYN_CONFIG:
149 disposition = INPUT_PASS_TO_ALL;
150 break;
151
152 case SYN_REPORT:
153 if (!dev->sync) {
154 dev->sync = 1;
155 disposition = INPUT_PASS_TO_HANDLERS;
156 }
157 break;
158 }
159 break;
160
161 case EV_KEY:
162 if (is_event_supported(code, dev->keybit, KEY_MAX) &&
163 !!test_bit(code, dev->key) != value) {
164
165 if (value != 2) {
166 __change_bit(code, dev->key);
167 if (value)
168 input_start_autorepeat(dev, code);
169 }
170
171 disposition = INPUT_PASS_TO_HANDLERS;
172 }
173 break;
174
175 case EV_SW:
176 if (is_event_supported(code, dev->swbit, SW_MAX) &&
177 !!test_bit(code, dev->sw) != value) {
178
179 __change_bit(code, dev->sw);
180 disposition = INPUT_PASS_TO_HANDLERS;
181 }
182 break;
183
184 case EV_ABS:
185 if (is_event_supported(code, dev->absbit, ABS_MAX)) {
186
187 value = input_defuzz_abs_event(value,
188 dev->abs[code], dev->absfuzz[code]);
189
190 if (dev->abs[code] != value) {
191 dev->abs[code] = value;
192 disposition = INPUT_PASS_TO_HANDLERS;
193 }
194 }
195 break;
196
197 case EV_REL:
198 if (is_event_supported(code, dev->relbit, REL_MAX) && value)
199 disposition = INPUT_PASS_TO_HANDLERS;
200
201 break;
202
203 case EV_MSC:
204 if (is_event_supported(code, dev->mscbit, MSC_MAX))
205 disposition = INPUT_PASS_TO_ALL;
206
207 break;
208
209 case EV_LED:
210 if (is_event_supported(code, dev->ledbit, LED_MAX) &&
211 !!test_bit(code, dev->led) != value) {
212
213 __change_bit(code, dev->led);
214 disposition = INPUT_PASS_TO_ALL;
215 }
216 break;
217
218 case EV_SND:
219 if (is_event_supported(code, dev->sndbit, SND_MAX)) {
220
221 if (!!test_bit(code, dev->snd) != !!value)
222 __change_bit(code, dev->snd);
223 disposition = INPUT_PASS_TO_ALL;
224 }
225 break;
226
227 case EV_REP:
228 if (code <= REP_MAX && value >= 0 && dev->rep[code] != value) {
229 dev->rep[code] = value;
230 disposition = INPUT_PASS_TO_ALL;
231 }
232 break;
233
234 case EV_FF:
235 if (value >= 0)
236 disposition = INPUT_PASS_TO_ALL;
237 break;
238 }
239
240 if (type != EV_SYN)
241 dev->sync = 0;
242
243 if ((disposition & INPUT_PASS_TO_DEVICE) && dev->event)
244 dev->event(dev, type, code, value);
245
246 if (disposition & INPUT_PASS_TO_HANDLERS)
247 input_pass_event(dev, type, code, value);
248 }
249
250 /**
251 * input_event() - report new input event
252 * @dev: device that generated the event
253 * @type: type of the event
254 * @code: event code
255 * @value: value of the event
256 *
257 * This function should be used by drivers implementing various input
258 * devices. See also input_inject_event().
259 */
260
261 void input_event(struct input_dev *dev,
262 unsigned int type, unsigned int code, int value)
263 {
264 unsigned long flags;
265
266 if (is_event_supported(type, dev->evbit, EV_MAX)) {
267
268 spin_lock_irqsave(&dev->event_lock, flags);
269 add_input_randomness(type, code, value);
270 input_handle_event(dev, type, code, value);
271 spin_unlock_irqrestore(&dev->event_lock, flags);
272 }
273 }
274 EXPORT_SYMBOL(input_event);
275
276 /**
277 * input_inject_event() - send input event from input handler
278 * @handle: input handle to send event through
279 * @type: type of the event
280 * @code: event code
281 * @value: value of the event
282 *
283 * Similar to input_event() but will ignore event if device is
284 * "grabbed" and handle injecting event is not the one that owns
285 * the device.
286 */
287 void input_inject_event(struct input_handle *handle,
288 unsigned int type, unsigned int code, int value)
289 {
290 struct input_dev *dev = handle->dev;
291 struct input_handle *grab;
292 unsigned long flags;
293
294 if (is_event_supported(type, dev->evbit, EV_MAX)) {
295 spin_lock_irqsave(&dev->event_lock, flags);
296
297 rcu_read_lock();
298 grab = rcu_dereference(dev->grab);
299 if (!grab || grab == handle)
300 input_handle_event(dev, type, code, value);
301 rcu_read_unlock();
302
303 spin_unlock_irqrestore(&dev->event_lock, flags);
304 }
305 }
306 EXPORT_SYMBOL(input_inject_event);
307
308 /**
309 * input_grab_device - grabs device for exclusive use
310 * @handle: input handle that wants to own the device
311 *
312 * When a device is grabbed by an input handle all events generated by
313 * the device are delivered only to this handle. Also events injected
314 * by other input handles are ignored while device is grabbed.
315 */
316 int input_grab_device(struct input_handle *handle)
317 {
318 struct input_dev *dev = handle->dev;
319 int retval;
320
321 retval = mutex_lock_interruptible(&dev->mutex);
322 if (retval)
323 return retval;
324
325 if (dev->grab) {
326 retval = -EBUSY;
327 goto out;
328 }
329
330 rcu_assign_pointer(dev->grab, handle);
331 synchronize_rcu();
332
333 out:
334 mutex_unlock(&dev->mutex);
335 return retval;
336 }
337 EXPORT_SYMBOL(input_grab_device);
338
339 static void __input_release_device(struct input_handle *handle)
340 {
341 struct input_dev *dev = handle->dev;
342
343 if (dev->grab == handle) {
344 rcu_assign_pointer(dev->grab, NULL);
345 /* Make sure input_pass_event() notices that grab is gone */
346 synchronize_rcu();
347
348 list_for_each_entry(handle, &dev->h_list, d_node)
349 if (handle->open && handle->handler->start)
350 handle->handler->start(handle);
351 }
352 }
353
354 /**
355 * input_release_device - release previously grabbed device
356 * @handle: input handle that owns the device
357 *
358 * Releases previously grabbed device so that other input handles can
359 * start receiving input events. Upon release all handlers attached
360 * to the device have their start() method called so they have a change
361 * to synchronize device state with the rest of the system.
362 */
363 void input_release_device(struct input_handle *handle)
364 {
365 struct input_dev *dev = handle->dev;
366
367 mutex_lock(&dev->mutex);
368 __input_release_device(handle);
369 mutex_unlock(&dev->mutex);
370 }
371 EXPORT_SYMBOL(input_release_device);
372
373 /**
374 * input_open_device - open input device
375 * @handle: handle through which device is being accessed
376 *
377 * This function should be called by input handlers when they
378 * want to start receive events from given input device.
379 */
380 int input_open_device(struct input_handle *handle)
381 {
382 struct input_dev *dev = handle->dev;
383 int retval;
384
385 retval = mutex_lock_interruptible(&dev->mutex);
386 if (retval)
387 return retval;
388
389 if (dev->going_away) {
390 retval = -ENODEV;
391 goto out;
392 }
393
394 handle->open++;
395
396 if (!dev->users++ && dev->open)
397 retval = dev->open(dev);
398
399 if (retval) {
400 dev->users--;
401 if (!--handle->open) {
402 /*
403 * Make sure we are not delivering any more events
404 * through this handle
405 */
406 synchronize_rcu();
407 }
408 }
409
410 out:
411 mutex_unlock(&dev->mutex);
412 return retval;
413 }
414 EXPORT_SYMBOL(input_open_device);
415
416 int input_flush_device(struct input_handle *handle, struct file *file)
417 {
418 struct input_dev *dev = handle->dev;
419 int retval;
420
421 retval = mutex_lock_interruptible(&dev->mutex);
422 if (retval)
423 return retval;
424
425 if (dev->flush)
426 retval = dev->flush(dev, file);
427
428 mutex_unlock(&dev->mutex);
429 return retval;
430 }
431 EXPORT_SYMBOL(input_flush_device);
432
433 /**
434 * input_close_device - close input device
435 * @handle: handle through which device is being accessed
436 *
437 * This function should be called by input handlers when they
438 * want to stop receive events from given input device.
439 */
440 void input_close_device(struct input_handle *handle)
441 {
442 struct input_dev *dev = handle->dev;
443
444 mutex_lock(&dev->mutex);
445
446 __input_release_device(handle);
447
448 if (!--dev->users && dev->close)
449 dev->close(dev);
450
451 if (!--handle->open) {
452 /*
453 * synchronize_rcu() makes sure that input_pass_event()
454 * completed and that no more input events are delivered
455 * through this handle
456 */
457 synchronize_rcu();
458 }
459
460 mutex_unlock(&dev->mutex);
461 }
462 EXPORT_SYMBOL(input_close_device);
463
464 /*
465 * Prepare device for unregistering
466 */
467 static void input_disconnect_device(struct input_dev *dev)
468 {
469 struct input_handle *handle;
470 int code;
471
472 /*
473 * Mark device as going away. Note that we take dev->mutex here
474 * not to protect access to dev->going_away but rather to ensure
475 * that there are no threads in the middle of input_open_device()
476 */
477 mutex_lock(&dev->mutex);
478 dev->going_away = 1;
479 mutex_unlock(&dev->mutex);
480
481 spin_lock_irq(&dev->event_lock);
482
483 /*
484 * Simulate keyup events for all pressed keys so that handlers
485 * are not left with "stuck" keys. The driver may continue
486 * generate events even after we done here but they will not
487 * reach any handlers.
488 */
489 if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
490 for (code = 0; code <= KEY_MAX; code++) {
491 if (is_event_supported(code, dev->keybit, KEY_MAX) &&
492 test_bit(code, dev->key)) {
493 input_pass_event(dev, EV_KEY, code, 0);
494 }
495 }
496 input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
497 }
498
499 list_for_each_entry(handle, &dev->h_list, d_node)
500 handle->open = 0;
501
502 spin_unlock_irq(&dev->event_lock);
503 }
504
505 static int input_fetch_keycode(struct input_dev *dev, int scancode)
506 {
507 switch (dev->keycodesize) {
508 case 1:
509 return ((u8 *)dev->keycode)[scancode];
510
511 case 2:
512 return ((u16 *)dev->keycode)[scancode];
513
514 default:
515 return ((u32 *)dev->keycode)[scancode];
516 }
517 }
518
519 static int input_default_getkeycode(struct input_dev *dev,
520 int scancode, int *keycode)
521 {
522 if (!dev->keycodesize)
523 return -EINVAL;
524
525 if (scancode < 0 || scancode >= dev->keycodemax)
526 return -EINVAL;
527
528 *keycode = input_fetch_keycode(dev, scancode);
529
530 return 0;
531 }
532
533 static int input_default_setkeycode(struct input_dev *dev,
534 int scancode, int keycode)
535 {
536 int old_keycode;
537 int i;
538
539 if (scancode < 0 || scancode >= dev->keycodemax)
540 return -EINVAL;
541
542 if (keycode < 0 || keycode > KEY_MAX)
543 return -EINVAL;
544
545 if (!dev->keycodesize)
546 return -EINVAL;
547
548 if (dev->keycodesize < sizeof(keycode) && (keycode >> (dev->keycodesize * 8)))
549 return -EINVAL;
550
551 switch (dev->keycodesize) {
552 case 1: {
553 u8 *k = (u8 *)dev->keycode;
554 old_keycode = k[scancode];
555 k[scancode] = keycode;
556 break;
557 }
558 case 2: {
559 u16 *k = (u16 *)dev->keycode;
560 old_keycode = k[scancode];
561 k[scancode] = keycode;
562 break;
563 }
564 default: {
565 u32 *k = (u32 *)dev->keycode;
566 old_keycode = k[scancode];
567 k[scancode] = keycode;
568 break;
569 }
570 }
571
572 clear_bit(old_keycode, dev->keybit);
573 set_bit(keycode, dev->keybit);
574
575 for (i = 0; i < dev->keycodemax; i++) {
576 if (input_fetch_keycode(dev, i) == old_keycode) {
577 set_bit(old_keycode, dev->keybit);
578 break; /* Setting the bit twice is useless, so break */
579 }
580 }
581
582 return 0;
583 }
584
585
586 #define MATCH_BIT(bit, max) \
587 for (i = 0; i < NBITS(max); i++) \
588 if ((id->bit[i] & dev->bit[i]) != id->bit[i]) \
589 break; \
590 if (i != NBITS(max)) \
591 continue;
592
593 static const struct input_device_id *input_match_device(const struct input_device_id *id,
594 struct input_dev *dev)
595 {
596 int i;
597
598 for (; id->flags || id->driver_info; id++) {
599
600 if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
601 if (id->bustype != dev->id.bustype)
602 continue;
603
604 if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
605 if (id->vendor != dev->id.vendor)
606 continue;
607
608 if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
609 if (id->product != dev->id.product)
610 continue;
611
612 if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
613 if (id->version != dev->id.version)
614 continue;
615
616 MATCH_BIT(evbit, EV_MAX);
617 MATCH_BIT(keybit, KEY_MAX);
618 MATCH_BIT(relbit, REL_MAX);
619 MATCH_BIT(absbit, ABS_MAX);
620 MATCH_BIT(mscbit, MSC_MAX);
621 MATCH_BIT(ledbit, LED_MAX);
622 MATCH_BIT(sndbit, SND_MAX);
623 MATCH_BIT(ffbit, FF_MAX);
624 MATCH_BIT(swbit, SW_MAX);
625
626 return id;
627 }
628
629 return NULL;
630 }
631
632 static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
633 {
634 const struct input_device_id *id;
635 int error;
636
637 if (handler->blacklist && input_match_device(handler->blacklist, dev))
638 return -ENODEV;
639
640 id = input_match_device(handler->id_table, dev);
641 if (!id)
642 return -ENODEV;
643
644 error = handler->connect(handler, dev, id);
645 if (error && error != -ENODEV)
646 printk(KERN_ERR
647 "input: failed to attach handler %s to device %s, "
648 "error: %d\n",
649 handler->name, kobject_name(&dev->dev.kobj), error);
650
651 return error;
652 }
653
654
655 #ifdef CONFIG_PROC_FS
656
657 static struct proc_dir_entry *proc_bus_input_dir;
658 static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
659 static int input_devices_state;
660
661 static inline void input_wakeup_procfs_readers(void)
662 {
663 input_devices_state++;
664 wake_up(&input_devices_poll_wait);
665 }
666
667 static unsigned int input_proc_devices_poll(struct file *file, poll_table *wait)
668 {
669 int state = input_devices_state;
670
671 poll_wait(file, &input_devices_poll_wait, wait);
672 if (state != input_devices_state)
673 return POLLIN | POLLRDNORM;
674
675 return 0;
676 }
677
678 static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
679 {
680 if (mutex_lock_interruptible(&input_mutex))
681 return NULL;
682
683 return seq_list_start(&input_dev_list, *pos);
684 }
685
686 static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
687 {
688 return seq_list_next(v, &input_dev_list, pos);
689 }
690
691 static void input_devices_seq_stop(struct seq_file *seq, void *v)
692 {
693 mutex_unlock(&input_mutex);
694 }
695
696 static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
697 unsigned long *bitmap, int max)
698 {
699 int i;
700
701 for (i = NBITS(max) - 1; i > 0; i--)
702 if (bitmap[i])
703 break;
704
705 seq_printf(seq, "B: %s=", name);
706 for (; i >= 0; i--)
707 seq_printf(seq, "%lx%s", bitmap[i], i > 0 ? " " : "");
708 seq_putc(seq, '\n');
709 }
710
711 static int input_devices_seq_show(struct seq_file *seq, void *v)
712 {
713 struct input_dev *dev = container_of(v, struct input_dev, node);
714 const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
715 struct input_handle *handle;
716
717 seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
718 dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
719
720 seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
721 seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
722 seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
723 seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
724 seq_printf(seq, "H: Handlers=");
725
726 list_for_each_entry(handle, &dev->h_list, d_node)
727 seq_printf(seq, "%s ", handle->name);
728 seq_putc(seq, '\n');
729
730 input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
731 if (test_bit(EV_KEY, dev->evbit))
732 input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
733 if (test_bit(EV_REL, dev->evbit))
734 input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
735 if (test_bit(EV_ABS, dev->evbit))
736 input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
737 if (test_bit(EV_MSC, dev->evbit))
738 input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
739 if (test_bit(EV_LED, dev->evbit))
740 input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
741 if (test_bit(EV_SND, dev->evbit))
742 input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
743 if (test_bit(EV_FF, dev->evbit))
744 input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
745 if (test_bit(EV_SW, dev->evbit))
746 input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);
747
748 seq_putc(seq, '\n');
749
750 kfree(path);
751 return 0;
752 }
753
754 static struct seq_operations input_devices_seq_ops = {
755 .start = input_devices_seq_start,
756 .next = input_devices_seq_next,
757 .stop = input_devices_seq_stop,
758 .show = input_devices_seq_show,
759 };
760
761 static int input_proc_devices_open(struct inode *inode, struct file *file)
762 {
763 return seq_open(file, &input_devices_seq_ops);
764 }
765
766 static const struct file_operations input_devices_fileops = {
767 .owner = THIS_MODULE,
768 .open = input_proc_devices_open,
769 .poll = input_proc_devices_poll,
770 .read = seq_read,
771 .llseek = seq_lseek,
772 .release = seq_release,
773 };
774
775 static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
776 {
777 if (mutex_lock_interruptible(&input_mutex))
778 return NULL;
779
780 seq->private = (void *)(unsigned long)*pos;
781 return seq_list_start(&input_handler_list, *pos);
782 }
783
784 static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
785 {
786 seq->private = (void *)(unsigned long)(*pos + 1);
787 return seq_list_next(v, &input_handler_list, pos);
788 }
789
790 static void input_handlers_seq_stop(struct seq_file *seq, void *v)
791 {
792 mutex_unlock(&input_mutex);
793 }
794
795 static int input_handlers_seq_show(struct seq_file *seq, void *v)
796 {
797 struct input_handler *handler = container_of(v, struct input_handler, node);
798
799 seq_printf(seq, "N: Number=%ld Name=%s",
800 (unsigned long)seq->private, handler->name);
801 if (handler->fops)
802 seq_printf(seq, " Minor=%d", handler->minor);
803 seq_putc(seq, '\n');
804
805 return 0;
806 }
807 static struct seq_operations input_handlers_seq_ops = {
808 .start = input_handlers_seq_start,
809 .next = input_handlers_seq_next,
810 .stop = input_handlers_seq_stop,
811 .show = input_handlers_seq_show,
812 };
813
814 static int input_proc_handlers_open(struct inode *inode, struct file *file)
815 {
816 return seq_open(file, &input_handlers_seq_ops);
817 }
818
819 static const struct file_operations input_handlers_fileops = {
820 .owner = THIS_MODULE,
821 .open = input_proc_handlers_open,
822 .read = seq_read,
823 .llseek = seq_lseek,
824 .release = seq_release,
825 };
826
827 static int __init input_proc_init(void)
828 {
829 struct proc_dir_entry *entry;
830
831 proc_bus_input_dir = proc_mkdir("input", proc_bus);
832 if (!proc_bus_input_dir)
833 return -ENOMEM;
834
835 proc_bus_input_dir->owner = THIS_MODULE;
836
837 entry = create_proc_entry("devices", 0, proc_bus_input_dir);
838 if (!entry)
839 goto fail1;
840
841 entry->owner = THIS_MODULE;
842 entry->proc_fops = &input_devices_fileops;
843
844 entry = create_proc_entry("handlers", 0, proc_bus_input_dir);
845 if (!entry)
846 goto fail2;
847
848 entry->owner = THIS_MODULE;
849 entry->proc_fops = &input_handlers_fileops;
850
851 return 0;
852
853 fail2: remove_proc_entry("devices", proc_bus_input_dir);
854 fail1: remove_proc_entry("input", proc_bus);
855 return -ENOMEM;
856 }
857
858 static void input_proc_exit(void)
859 {
860 remove_proc_entry("devices", proc_bus_input_dir);
861 remove_proc_entry("handlers", proc_bus_input_dir);
862 remove_proc_entry("input", proc_bus);
863 }
864
865 #else /* !CONFIG_PROC_FS */
866 static inline void input_wakeup_procfs_readers(void) { }
867 static inline int input_proc_init(void) { return 0; }
868 static inline void input_proc_exit(void) { }
869 #endif
870
871 #define INPUT_DEV_STRING_ATTR_SHOW(name) \
872 static ssize_t input_dev_show_##name(struct device *dev, \
873 struct device_attribute *attr, \
874 char *buf) \
875 { \
876 struct input_dev *input_dev = to_input_dev(dev); \
877 \
878 return scnprintf(buf, PAGE_SIZE, "%s\n", \
879 input_dev->name ? input_dev->name : ""); \
880 } \
881 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
882
883 INPUT_DEV_STRING_ATTR_SHOW(name);
884 INPUT_DEV_STRING_ATTR_SHOW(phys);
885 INPUT_DEV_STRING_ATTR_SHOW(uniq);
886
887 static int input_print_modalias_bits(char *buf, int size,
888 char name, unsigned long *bm,
889 unsigned int min_bit, unsigned int max_bit)
890 {
891 int len = 0, i;
892
893 len += snprintf(buf, max(size, 0), "%c", name);
894 for (i = min_bit; i < max_bit; i++)
895 if (bm[LONG(i)] & BIT(i))
896 len += snprintf(buf + len, max(size - len, 0), "%X,", i);
897 return len;
898 }
899
900 static int input_print_modalias(char *buf, int size, struct input_dev *id,
901 int add_cr)
902 {
903 int len;
904
905 len = snprintf(buf, max(size, 0),
906 "input:b%04Xv%04Xp%04Xe%04X-",
907 id->id.bustype, id->id.vendor,
908 id->id.product, id->id.version);
909
910 len += input_print_modalias_bits(buf + len, size - len,
911 'e', id->evbit, 0, EV_MAX);
912 len += input_print_modalias_bits(buf + len, size - len,
913 'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
914 len += input_print_modalias_bits(buf + len, size - len,
915 'r', id->relbit, 0, REL_MAX);
916 len += input_print_modalias_bits(buf + len, size - len,
917 'a', id->absbit, 0, ABS_MAX);
918 len += input_print_modalias_bits(buf + len, size - len,
919 'm', id->mscbit, 0, MSC_MAX);
920 len += input_print_modalias_bits(buf + len, size - len,
921 'l', id->ledbit, 0, LED_MAX);
922 len += input_print_modalias_bits(buf + len, size - len,
923 's', id->sndbit, 0, SND_MAX);
924 len += input_print_modalias_bits(buf + len, size - len,
925 'f', id->ffbit, 0, FF_MAX);
926 len += input_print_modalias_bits(buf + len, size - len,
927 'w', id->swbit, 0, SW_MAX);
928
929 if (add_cr)
930 len += snprintf(buf + len, max(size - len, 0), "\n");
931
932 return len;
933 }
934
935 static ssize_t input_dev_show_modalias(struct device *dev,
936 struct device_attribute *attr,
937 char *buf)
938 {
939 struct input_dev *id = to_input_dev(dev);
940 ssize_t len;
941
942 len = input_print_modalias(buf, PAGE_SIZE, id, 1);
943
944 return min_t(int, len, PAGE_SIZE);
945 }
946 static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
947
948 static struct attribute *input_dev_attrs[] = {
949 &dev_attr_name.attr,
950 &dev_attr_phys.attr,
951 &dev_attr_uniq.attr,
952 &dev_attr_modalias.attr,
953 NULL
954 };
955
956 static struct attribute_group input_dev_attr_group = {
957 .attrs = input_dev_attrs,
958 };
959
960 #define INPUT_DEV_ID_ATTR(name) \
961 static ssize_t input_dev_show_id_##name(struct device *dev, \
962 struct device_attribute *attr, \
963 char *buf) \
964 { \
965 struct input_dev *input_dev = to_input_dev(dev); \
966 return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name); \
967 } \
968 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
969
970 INPUT_DEV_ID_ATTR(bustype);
971 INPUT_DEV_ID_ATTR(vendor);
972 INPUT_DEV_ID_ATTR(product);
973 INPUT_DEV_ID_ATTR(version);
974
975 static struct attribute *input_dev_id_attrs[] = {
976 &dev_attr_bustype.attr,
977 &dev_attr_vendor.attr,
978 &dev_attr_product.attr,
979 &dev_attr_version.attr,
980 NULL
981 };
982
983 static struct attribute_group input_dev_id_attr_group = {
984 .name = "id",
985 .attrs = input_dev_id_attrs,
986 };
987
988 static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
989 int max, int add_cr)
990 {
991 int i;
992 int len = 0;
993
994 for (i = NBITS(max) - 1; i > 0; i--)
995 if (bitmap[i])
996 break;
997
998 for (; i >= 0; i--)
999 len += snprintf(buf + len, max(buf_size - len, 0),
1000 "%lx%s", bitmap[i], i > 0 ? " " : "");
1001
1002 if (add_cr)
1003 len += snprintf(buf + len, max(buf_size - len, 0), "\n");
1004
1005 return len;
1006 }
1007
1008 #define INPUT_DEV_CAP_ATTR(ev, bm) \
1009 static ssize_t input_dev_show_cap_##bm(struct device *dev, \
1010 struct device_attribute *attr, \
1011 char *buf) \
1012 { \
1013 struct input_dev *input_dev = to_input_dev(dev); \
1014 int len = input_print_bitmap(buf, PAGE_SIZE, \
1015 input_dev->bm##bit, ev##_MAX, 1); \
1016 return min_t(int, len, PAGE_SIZE); \
1017 } \
1018 static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
1019
1020 INPUT_DEV_CAP_ATTR(EV, ev);
1021 INPUT_DEV_CAP_ATTR(KEY, key);
1022 INPUT_DEV_CAP_ATTR(REL, rel);
1023 INPUT_DEV_CAP_ATTR(ABS, abs);
1024 INPUT_DEV_CAP_ATTR(MSC, msc);
1025 INPUT_DEV_CAP_ATTR(LED, led);
1026 INPUT_DEV_CAP_ATTR(SND, snd);
1027 INPUT_DEV_CAP_ATTR(FF, ff);
1028 INPUT_DEV_CAP_ATTR(SW, sw);
1029
1030 static struct attribute *input_dev_caps_attrs[] = {
1031 &dev_attr_ev.attr,
1032 &dev_attr_key.attr,
1033 &dev_attr_rel.attr,
1034 &dev_attr_abs.attr,
1035 &dev_attr_msc.attr,
1036 &dev_attr_led.attr,
1037 &dev_attr_snd.attr,
1038 &dev_attr_ff.attr,
1039 &dev_attr_sw.attr,
1040 NULL
1041 };
1042
1043 static struct attribute_group input_dev_caps_attr_group = {
1044 .name = "capabilities",
1045 .attrs = input_dev_caps_attrs,
1046 };
1047
1048 static struct attribute_group *input_dev_attr_groups[] = {
1049 &input_dev_attr_group,
1050 &input_dev_id_attr_group,
1051 &input_dev_caps_attr_group,
1052 NULL
1053 };
1054
1055 static void input_dev_release(struct device *device)
1056 {
1057 struct input_dev *dev = to_input_dev(device);
1058
1059 input_ff_destroy(dev);
1060 kfree(dev);
1061
1062 module_put(THIS_MODULE);
1063 }
1064
1065 /*
1066 * Input uevent interface - loading event handlers based on
1067 * device bitfields.
1068 */
1069 static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
1070 const char *name, unsigned long *bitmap, int max)
1071 {
1072 int len;
1073
1074 if (add_uevent_var(env, "%s=", name))
1075 return -ENOMEM;
1076
1077 len = input_print_bitmap(&env->buf[env->buflen - 1],
1078 sizeof(env->buf) - env->buflen,
1079 bitmap, max, 0);
1080 if (len >= (sizeof(env->buf) - env->buflen))
1081 return -ENOMEM;
1082
1083 env->buflen += len;
1084 return 0;
1085 }
1086
1087 static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
1088 struct input_dev *dev)
1089 {
1090 int len;
1091
1092 if (add_uevent_var(env, "MODALIAS="))
1093 return -ENOMEM;
1094
1095 len = input_print_modalias(&env->buf[env->buflen - 1],
1096 sizeof(env->buf) - env->buflen,
1097 dev, 0);
1098 if (len >= (sizeof(env->buf) - env->buflen))
1099 return -ENOMEM;
1100
1101 env->buflen += len;
1102 return 0;
1103 }
1104
1105 #define INPUT_ADD_HOTPLUG_VAR(fmt, val...) \
1106 do { \
1107 int err = add_uevent_var(env, fmt, val); \
1108 if (err) \
1109 return err; \
1110 } while (0)
1111
1112 #define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max) \
1113 do { \
1114 int err = input_add_uevent_bm_var(env, name, bm, max); \
1115 if (err) \
1116 return err; \
1117 } while (0)
1118
1119 #define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev) \
1120 do { \
1121 int err = input_add_uevent_modalias_var(env, dev); \
1122 if (err) \
1123 return err; \
1124 } while (0)
1125
1126 static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
1127 {
1128 struct input_dev *dev = to_input_dev(device);
1129
1130 INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
1131 dev->id.bustype, dev->id.vendor,
1132 dev->id.product, dev->id.version);
1133 if (dev->name)
1134 INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
1135 if (dev->phys)
1136 INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
1137 if (dev->uniq)
1138 INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
1139
1140 INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
1141 if (test_bit(EV_KEY, dev->evbit))
1142 INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
1143 if (test_bit(EV_REL, dev->evbit))
1144 INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
1145 if (test_bit(EV_ABS, dev->evbit))
1146 INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
1147 if (test_bit(EV_MSC, dev->evbit))
1148 INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
1149 if (test_bit(EV_LED, dev->evbit))
1150 INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
1151 if (test_bit(EV_SND, dev->evbit))
1152 INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
1153 if (test_bit(EV_FF, dev->evbit))
1154 INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
1155 if (test_bit(EV_SW, dev->evbit))
1156 INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
1157
1158 INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
1159
1160 return 0;
1161 }
1162
1163 static struct device_type input_dev_type = {
1164 .groups = input_dev_attr_groups,
1165 .release = input_dev_release,
1166 .uevent = input_dev_uevent,
1167 };
1168
1169 struct class input_class = {
1170 .name = "input",
1171 };
1172 EXPORT_SYMBOL_GPL(input_class);
1173
1174 /**
1175 * input_allocate_device - allocate memory for new input device
1176 *
1177 * Returns prepared struct input_dev or NULL.
1178 *
1179 * NOTE: Use input_free_device() to free devices that have not been
1180 * registered; input_unregister_device() should be used for already
1181 * registered devices.
1182 */
1183 struct input_dev *input_allocate_device(void)
1184 {
1185 struct input_dev *dev;
1186
1187 dev = kzalloc(sizeof(struct input_dev), GFP_KERNEL);
1188 if (dev) {
1189 dev->dev.type = &input_dev_type;
1190 dev->dev.class = &input_class;
1191 device_initialize(&dev->dev);
1192 mutex_init(&dev->mutex);
1193 spin_lock_init(&dev->event_lock);
1194 INIT_LIST_HEAD(&dev->h_list);
1195 INIT_LIST_HEAD(&dev->node);
1196
1197 __module_get(THIS_MODULE);
1198 }
1199
1200 return dev;
1201 }
1202 EXPORT_SYMBOL(input_allocate_device);
1203
1204 /**
1205 * input_free_device - free memory occupied by input_dev structure
1206 * @dev: input device to free
1207 *
1208 * This function should only be used if input_register_device()
1209 * was not called yet or if it failed. Once device was registered
1210 * use input_unregister_device() and memory will be freed once last
1211 * reference to the device is dropped.
1212 *
1213 * Device should be allocated by input_allocate_device().
1214 *
1215 * NOTE: If there are references to the input device then memory
1216 * will not be freed until last reference is dropped.
1217 */
1218 void input_free_device(struct input_dev *dev)
1219 {
1220 if (dev)
1221 input_put_device(dev);
1222 }
1223 EXPORT_SYMBOL(input_free_device);
1224
1225 /**
1226 * input_set_capability - mark device as capable of a certain event
1227 * @dev: device that is capable of emitting or accepting event
1228 * @type: type of the event (EV_KEY, EV_REL, etc...)
1229 * @code: event code
1230 *
1231 * In addition to setting up corresponding bit in appropriate capability
1232 * bitmap the function also adjusts dev->evbit.
1233 */
1234 void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
1235 {
1236 switch (type) {
1237 case EV_KEY:
1238 __set_bit(code, dev->keybit);
1239 break;
1240
1241 case EV_REL:
1242 __set_bit(code, dev->relbit);
1243 break;
1244
1245 case EV_ABS:
1246 __set_bit(code, dev->absbit);
1247 break;
1248
1249 case EV_MSC:
1250 __set_bit(code, dev->mscbit);
1251 break;
1252
1253 case EV_SW:
1254 __set_bit(code, dev->swbit);
1255 break;
1256
1257 case EV_LED:
1258 __set_bit(code, dev->ledbit);
1259 break;
1260
1261 case EV_SND:
1262 __set_bit(code, dev->sndbit);
1263 break;
1264
1265 case EV_FF:
1266 __set_bit(code, dev->ffbit);
1267 break;
1268
1269 default:
1270 printk(KERN_ERR
1271 "input_set_capability: unknown type %u (code %u)\n",
1272 type, code);
1273 dump_stack();
1274 return;
1275 }
1276
1277 __set_bit(type, dev->evbit);
1278 }
1279 EXPORT_SYMBOL(input_set_capability);
1280
1281 /**
1282 * input_register_device - register device with input core
1283 * @dev: device to be registered
1284 *
1285 * This function registers device with input core. The device must be
1286 * allocated with input_allocate_device() and all it's capabilities
1287 * set up before registering.
1288 * If function fails the device must be freed with input_free_device().
1289 * Once device has been successfully registered it can be unregistered
1290 * with input_unregister_device(); input_free_device() should not be
1291 * called in this case.
1292 */
1293 int input_register_device(struct input_dev *dev)
1294 {
1295 static atomic_t input_no = ATOMIC_INIT(0);
1296 struct input_handler *handler;
1297 const char *path;
1298 int error;
1299
1300 __set_bit(EV_SYN, dev->evbit);
1301
1302 /*
1303 * If delay and period are pre-set by the driver, then autorepeating
1304 * is handled by the driver itself and we don't do it in input.c.
1305 */
1306
1307 init_timer(&dev->timer);
1308 if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD]) {
1309 dev->timer.data = (long) dev;
1310 dev->timer.function = input_repeat_key;
1311 dev->rep[REP_DELAY] = 250;
1312 dev->rep[REP_PERIOD] = 33;
1313 }
1314
1315 if (!dev->getkeycode)
1316 dev->getkeycode = input_default_getkeycode;
1317
1318 if (!dev->setkeycode)
1319 dev->setkeycode = input_default_setkeycode;
1320
1321 snprintf(dev->dev.bus_id, sizeof(dev->dev.bus_id),
1322 "input%ld", (unsigned long) atomic_inc_return(&input_no) - 1);
1323
1324 if (dev->cdev.dev)
1325 dev->dev.parent = dev->cdev.dev;
1326
1327 error = device_add(&dev->dev);
1328 if (error)
1329 return error;
1330
1331 path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1332 printk(KERN_INFO "input: %s as %s\n",
1333 dev->name ? dev->name : "Unspecified device", path ? path : "N/A");
1334 kfree(path);
1335
1336 error = mutex_lock_interruptible(&input_mutex);
1337 if (error) {
1338 device_del(&dev->dev);
1339 return error;
1340 }
1341
1342 list_add_tail(&dev->node, &input_dev_list);
1343
1344 list_for_each_entry(handler, &input_handler_list, node)
1345 input_attach_handler(dev, handler);
1346
1347 input_wakeup_procfs_readers();
1348
1349 mutex_unlock(&input_mutex);
1350
1351 return 0;
1352 }
1353 EXPORT_SYMBOL(input_register_device);
1354
1355 /**
1356 * input_unregister_device - unregister previously registered device
1357 * @dev: device to be unregistered
1358 *
1359 * This function unregisters an input device. Once device is unregistered
1360 * the caller should not try to access it as it may get freed at any moment.
1361 */
1362 void input_unregister_device(struct input_dev *dev)
1363 {
1364 struct input_handle *handle, *next;
1365
1366 input_disconnect_device(dev);
1367
1368 mutex_lock(&input_mutex);
1369
1370 list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
1371 handle->handler->disconnect(handle);
1372 WARN_ON(!list_empty(&dev->h_list));
1373
1374 del_timer_sync(&dev->timer);
1375 list_del_init(&dev->node);
1376
1377 input_wakeup_procfs_readers();
1378
1379 mutex_unlock(&input_mutex);
1380
1381 device_unregister(&dev->dev);
1382 }
1383 EXPORT_SYMBOL(input_unregister_device);
1384
1385 /**
1386 * input_register_handler - register a new input handler
1387 * @handler: handler to be registered
1388 *
1389 * This function registers a new input handler (interface) for input
1390 * devices in the system and attaches it to all input devices that
1391 * are compatible with the handler.
1392 */
1393 int input_register_handler(struct input_handler *handler)
1394 {
1395 struct input_dev *dev;
1396 int retval;
1397
1398 retval = mutex_lock_interruptible(&input_mutex);
1399 if (retval)
1400 return retval;
1401
1402 INIT_LIST_HEAD(&handler->h_list);
1403
1404 if (handler->fops != NULL) {
1405 if (input_table[handler->minor >> 5]) {
1406 retval = -EBUSY;
1407 goto out;
1408 }
1409 input_table[handler->minor >> 5] = handler;
1410 }
1411
1412 list_add_tail(&handler->node, &input_handler_list);
1413
1414 list_for_each_entry(dev, &input_dev_list, node)
1415 input_attach_handler(dev, handler);
1416
1417 input_wakeup_procfs_readers();
1418
1419 out:
1420 mutex_unlock(&input_mutex);
1421 return retval;
1422 }
1423 EXPORT_SYMBOL(input_register_handler);
1424
1425 /**
1426 * input_unregister_handler - unregisters an input handler
1427 * @handler: handler to be unregistered
1428 *
1429 * This function disconnects a handler from its input devices and
1430 * removes it from lists of known handlers.
1431 */
1432 void input_unregister_handler(struct input_handler *handler)
1433 {
1434 struct input_handle *handle, *next;
1435
1436 mutex_lock(&input_mutex);
1437
1438 list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
1439 handler->disconnect(handle);
1440 WARN_ON(!list_empty(&handler->h_list));
1441
1442 list_del_init(&handler->node);
1443
1444 if (handler->fops != NULL)
1445 input_table[handler->minor >> 5] = NULL;
1446
1447 input_wakeup_procfs_readers();
1448
1449 mutex_unlock(&input_mutex);
1450 }
1451 EXPORT_SYMBOL(input_unregister_handler);
1452
1453 /**
1454 * input_register_handle - register a new input handle
1455 * @handle: handle to register
1456 *
1457 * This function puts a new input handle onto device's
1458 * and handler's lists so that events can flow through
1459 * it once it is opened using input_open_device().
1460 *
1461 * This function is supposed to be called from handler's
1462 * connect() method.
1463 */
1464 int input_register_handle(struct input_handle *handle)
1465 {
1466 struct input_handler *handler = handle->handler;
1467 struct input_dev *dev = handle->dev;
1468 int error;
1469
1470 /*
1471 * We take dev->mutex here to prevent race with
1472 * input_release_device().
1473 */
1474 error = mutex_lock_interruptible(&dev->mutex);
1475 if (error)
1476 return error;
1477 list_add_tail_rcu(&handle->d_node, &dev->h_list);
1478 mutex_unlock(&dev->mutex);
1479 synchronize_rcu();
1480
1481 /*
1482 * Since we are supposed to be called from ->connect()
1483 * which is mutually exclusive with ->disconnect()
1484 * we can't be racing with input_unregister_handle()
1485 * and so separate lock is not needed here.
1486 */
1487 list_add_tail(&handle->h_node, &handler->h_list);
1488
1489 if (handler->start)
1490 handler->start(handle);
1491
1492 return 0;
1493 }
1494 EXPORT_SYMBOL(input_register_handle);
1495
1496 /**
1497 * input_unregister_handle - unregister an input handle
1498 * @handle: handle to unregister
1499 *
1500 * This function removes input handle from device's
1501 * and handler's lists.
1502 *
1503 * This function is supposed to be called from handler's
1504 * disconnect() method.
1505 */
1506 void input_unregister_handle(struct input_handle *handle)
1507 {
1508 struct input_dev *dev = handle->dev;
1509
1510 list_del_init(&handle->h_node);
1511
1512 /*
1513 * Take dev->mutex to prevent race with input_release_device().
1514 */
1515 mutex_lock(&dev->mutex);
1516 list_del_rcu(&handle->d_node);
1517 mutex_unlock(&dev->mutex);
1518 synchronize_rcu();
1519 }
1520 EXPORT_SYMBOL(input_unregister_handle);
1521
1522 static int input_open_file(struct inode *inode, struct file *file)
1523 {
1524 struct input_handler *handler = input_table[iminor(inode) >> 5];
1525 const struct file_operations *old_fops, *new_fops = NULL;
1526 int err;
1527
1528 /* No load-on-demand here? */
1529 if (!handler || !(new_fops = fops_get(handler->fops)))
1530 return -ENODEV;
1531
1532 /*
1533 * That's _really_ odd. Usually NULL ->open means "nothing special",
1534 * not "no device". Oh, well...
1535 */
1536 if (!new_fops->open) {
1537 fops_put(new_fops);
1538 return -ENODEV;
1539 }
1540 old_fops = file->f_op;
1541 file->f_op = new_fops;
1542
1543 err = new_fops->open(inode, file);
1544
1545 if (err) {
1546 fops_put(file->f_op);
1547 file->f_op = fops_get(old_fops);
1548 }
1549 fops_put(old_fops);
1550 return err;
1551 }
1552
1553 static const struct file_operations input_fops = {
1554 .owner = THIS_MODULE,
1555 .open = input_open_file,
1556 };
1557
1558 static int __init input_init(void)
1559 {
1560 int err;
1561
1562 err = class_register(&input_class);
1563 if (err) {
1564 printk(KERN_ERR "input: unable to register input_dev class\n");
1565 return err;
1566 }
1567
1568 err = input_proc_init();
1569 if (err)
1570 goto fail1;
1571
1572 err = register_chrdev(INPUT_MAJOR, "input", &input_fops);
1573 if (err) {
1574 printk(KERN_ERR "input: unable to register char major %d", INPUT_MAJOR);
1575 goto fail2;
1576 }
1577
1578 return 0;
1579
1580 fail2: input_proc_exit();
1581 fail1: class_unregister(&input_class);
1582 return err;
1583 }
1584
1585 static void __exit input_exit(void)
1586 {
1587 input_proc_exit();
1588 unregister_chrdev(INPUT_MAJOR, "input");
1589 class_unregister(&input_class);
1590 }
1591
1592 subsys_initcall(input_init);
1593 module_exit(input_exit);
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