Line data Source code
1 : // SPDX-License-Identifier: GPL-2.0-only
2 : /*
3 : * The input core
4 : *
5 : * Copyright (c) 1999-2002 Vojtech Pavlik
6 : */
7 :
8 :
9 : #define pr_fmt(fmt) KBUILD_BASENAME ": " fmt
10 :
11 : #include <linux/init.h>
12 : #include <linux/types.h>
13 : #include <linux/idr.h>
14 : #include <linux/input/mt.h>
15 : #include <linux/module.h>
16 : #include <linux/slab.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/pm.h>
23 : #include <linux/poll.h>
24 : #include <linux/device.h>
25 : #include <linux/kstrtox.h>
26 : #include <linux/mutex.h>
27 : #include <linux/rcupdate.h>
28 : #include "input-compat.h"
29 : #include "input-core-private.h"
30 : #include "input-poller.h"
31 :
32 : MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
33 : MODULE_DESCRIPTION("Input core");
34 : MODULE_LICENSE("GPL");
35 :
36 : #define INPUT_MAX_CHAR_DEVICES 1024
37 : #define INPUT_FIRST_DYNAMIC_DEV 256
38 : static DEFINE_IDA(input_ida);
39 :
40 : static LIST_HEAD(input_dev_list);
41 : static LIST_HEAD(input_handler_list);
42 :
43 : /*
44 : * input_mutex protects access to both input_dev_list and input_handler_list.
45 : * This also causes input_[un]register_device and input_[un]register_handler
46 : * be mutually exclusive which simplifies locking in drivers implementing
47 : * input handlers.
48 : */
49 : static DEFINE_MUTEX(input_mutex);
50 :
51 : static const struct input_value input_value_sync = { EV_SYN, SYN_REPORT, 1 };
52 :
53 : static const unsigned int input_max_code[EV_CNT] = {
54 : [EV_KEY] = KEY_MAX,
55 : [EV_REL] = REL_MAX,
56 : [EV_ABS] = ABS_MAX,
57 : [EV_MSC] = MSC_MAX,
58 : [EV_SW] = SW_MAX,
59 : [EV_LED] = LED_MAX,
60 : [EV_SND] = SND_MAX,
61 : [EV_FF] = FF_MAX,
62 : };
63 :
64 0 : static inline int is_event_supported(unsigned int code,
65 : unsigned long *bm, unsigned int max)
66 : {
67 0 : return code <= max && test_bit(code, bm);
68 : }
69 :
70 0 : static int input_defuzz_abs_event(int value, int old_val, int fuzz)
71 : {
72 0 : if (fuzz) {
73 0 : if (value > old_val - fuzz / 2 && value < old_val + fuzz / 2)
74 : return old_val;
75 :
76 0 : if (value > old_val - fuzz && value < old_val + fuzz)
77 0 : return (old_val * 3 + value) / 4;
78 :
79 0 : if (value > old_val - fuzz * 2 && value < old_val + fuzz * 2)
80 0 : return (old_val + value) / 2;
81 : }
82 :
83 : return value;
84 : }
85 :
86 0 : static void input_start_autorepeat(struct input_dev *dev, int code)
87 : {
88 0 : if (test_bit(EV_REP, dev->evbit) &&
89 0 : dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] &&
90 0 : dev->timer.function) {
91 0 : dev->repeat_key = code;
92 0 : mod_timer(&dev->timer,
93 0 : jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
94 : }
95 0 : }
96 :
97 : static void input_stop_autorepeat(struct input_dev *dev)
98 : {
99 0 : del_timer(&dev->timer);
100 : }
101 :
102 : /*
103 : * Pass event first through all filters and then, if event has not been
104 : * filtered out, through all open handles. This function is called with
105 : * dev->event_lock held and interrupts disabled.
106 : */
107 0 : static unsigned int input_to_handler(struct input_handle *handle,
108 : struct input_value *vals, unsigned int count)
109 : {
110 0 : struct input_handler *handler = handle->handler;
111 0 : struct input_value *end = vals;
112 : struct input_value *v;
113 :
114 0 : if (handler->filter) {
115 0 : for (v = vals; v != vals + count; v++) {
116 0 : if (handler->filter(handle, v->type, v->code, v->value))
117 0 : continue;
118 0 : if (end != v)
119 0 : *end = *v;
120 0 : end++;
121 : }
122 0 : count = end - vals;
123 : }
124 :
125 0 : if (!count)
126 : return 0;
127 :
128 0 : if (handler->events)
129 0 : handler->events(handle, vals, count);
130 0 : else if (handler->event)
131 0 : for (v = vals; v != vals + count; v++)
132 0 : handler->event(handle, v->type, v->code, v->value);
133 :
134 : return count;
135 : }
136 :
137 : /*
138 : * Pass values first through all filters and then, if event has not been
139 : * filtered out, through all open handles. This function is called with
140 : * dev->event_lock held and interrupts disabled.
141 : */
142 0 : static void input_pass_values(struct input_dev *dev,
143 : struct input_value *vals, unsigned int count)
144 : {
145 : struct input_handle *handle;
146 : struct input_value *v;
147 :
148 : lockdep_assert_held(&dev->event_lock);
149 :
150 0 : if (!count)
151 : return;
152 :
153 : rcu_read_lock();
154 :
155 0 : handle = rcu_dereference(dev->grab);
156 0 : if (handle) {
157 0 : count = input_to_handler(handle, vals, count);
158 : } else {
159 0 : list_for_each_entry_rcu(handle, &dev->h_list, d_node)
160 0 : if (handle->open) {
161 0 : count = input_to_handler(handle, vals, count);
162 0 : if (!count)
163 : break;
164 : }
165 : }
166 :
167 : rcu_read_unlock();
168 :
169 : /* trigger auto repeat for key events */
170 0 : if (test_bit(EV_REP, dev->evbit) && test_bit(EV_KEY, dev->evbit)) {
171 0 : for (v = vals; v != vals + count; v++) {
172 0 : if (v->type == EV_KEY && v->value != 2) {
173 0 : if (v->value)
174 0 : input_start_autorepeat(dev, v->code);
175 : else
176 : input_stop_autorepeat(dev);
177 : }
178 : }
179 : }
180 : }
181 :
182 : #define INPUT_IGNORE_EVENT 0
183 : #define INPUT_PASS_TO_HANDLERS 1
184 : #define INPUT_PASS_TO_DEVICE 2
185 : #define INPUT_SLOT 4
186 : #define INPUT_FLUSH 8
187 : #define INPUT_PASS_TO_ALL (INPUT_PASS_TO_HANDLERS | INPUT_PASS_TO_DEVICE)
188 :
189 0 : static int input_handle_abs_event(struct input_dev *dev,
190 : unsigned int code, int *pval)
191 : {
192 0 : struct input_mt *mt = dev->mt;
193 0 : bool is_new_slot = false;
194 : bool is_mt_event;
195 : int *pold;
196 :
197 0 : if (code == ABS_MT_SLOT) {
198 : /*
199 : * "Stage" the event; we'll flush it later, when we
200 : * get actual touch data.
201 : */
202 0 : if (mt && *pval >= 0 && *pval < mt->num_slots)
203 0 : mt->slot = *pval;
204 :
205 : return INPUT_IGNORE_EVENT;
206 : }
207 :
208 0 : is_mt_event = input_is_mt_value(code);
209 :
210 0 : if (!is_mt_event) {
211 0 : pold = &dev->absinfo[code].value;
212 0 : } else if (mt) {
213 0 : pold = &mt->slots[mt->slot].abs[code - ABS_MT_FIRST];
214 0 : is_new_slot = mt->slot != dev->absinfo[ABS_MT_SLOT].value;
215 : } else {
216 : /*
217 : * Bypass filtering for multi-touch events when
218 : * not employing slots.
219 : */
220 : pold = NULL;
221 : }
222 :
223 0 : if (pold) {
224 0 : *pval = input_defuzz_abs_event(*pval, *pold,
225 0 : dev->absinfo[code].fuzz);
226 0 : if (*pold == *pval)
227 : return INPUT_IGNORE_EVENT;
228 :
229 0 : *pold = *pval;
230 : }
231 :
232 : /* Flush pending "slot" event */
233 0 : if (is_new_slot) {
234 0 : dev->absinfo[ABS_MT_SLOT].value = mt->slot;
235 : return INPUT_PASS_TO_HANDLERS | INPUT_SLOT;
236 : }
237 :
238 : return INPUT_PASS_TO_HANDLERS;
239 : }
240 :
241 0 : static int input_get_disposition(struct input_dev *dev,
242 : unsigned int type, unsigned int code, int *pval)
243 : {
244 0 : int disposition = INPUT_IGNORE_EVENT;
245 0 : int value = *pval;
246 :
247 : /* filter-out events from inhibited devices */
248 0 : if (dev->inhibited)
249 : return INPUT_IGNORE_EVENT;
250 :
251 0 : switch (type) {
252 :
253 : case EV_SYN:
254 0 : switch (code) {
255 : case SYN_CONFIG:
256 0 : disposition = INPUT_PASS_TO_ALL;
257 0 : break;
258 :
259 : case SYN_REPORT:
260 0 : disposition = INPUT_PASS_TO_HANDLERS | INPUT_FLUSH;
261 0 : break;
262 : case SYN_MT_REPORT:
263 0 : disposition = INPUT_PASS_TO_HANDLERS;
264 0 : break;
265 : }
266 : break;
267 :
268 : case EV_KEY:
269 0 : if (is_event_supported(code, dev->keybit, KEY_MAX)) {
270 :
271 : /* auto-repeat bypasses state updates */
272 0 : if (value == 2) {
273 : disposition = INPUT_PASS_TO_HANDLERS;
274 : break;
275 : }
276 :
277 0 : if (!!test_bit(code, dev->key) != !!value) {
278 :
279 0 : __change_bit(code, dev->key);
280 : disposition = INPUT_PASS_TO_HANDLERS;
281 : }
282 : }
283 : break;
284 :
285 : case EV_SW:
286 0 : if (is_event_supported(code, dev->swbit, SW_MAX) &&
287 0 : !!test_bit(code, dev->sw) != !!value) {
288 :
289 0 : __change_bit(code, dev->sw);
290 : disposition = INPUT_PASS_TO_HANDLERS;
291 : }
292 : break;
293 :
294 : case EV_ABS:
295 0 : if (is_event_supported(code, dev->absbit, ABS_MAX))
296 0 : disposition = input_handle_abs_event(dev, code, &value);
297 :
298 : break;
299 :
300 : case EV_REL:
301 0 : if (is_event_supported(code, dev->relbit, REL_MAX) && value)
302 0 : disposition = INPUT_PASS_TO_HANDLERS;
303 :
304 : break;
305 :
306 : case EV_MSC:
307 0 : if (is_event_supported(code, dev->mscbit, MSC_MAX))
308 0 : disposition = INPUT_PASS_TO_ALL;
309 :
310 : break;
311 :
312 : case EV_LED:
313 0 : if (is_event_supported(code, dev->ledbit, LED_MAX) &&
314 0 : !!test_bit(code, dev->led) != !!value) {
315 :
316 0 : __change_bit(code, dev->led);
317 : disposition = INPUT_PASS_TO_ALL;
318 : }
319 : break;
320 :
321 : case EV_SND:
322 0 : if (is_event_supported(code, dev->sndbit, SND_MAX)) {
323 :
324 0 : if (!!test_bit(code, dev->snd) != !!value)
325 0 : __change_bit(code, dev->snd);
326 : disposition = INPUT_PASS_TO_ALL;
327 : }
328 : break;
329 :
330 : case EV_REP:
331 0 : if (code <= REP_MAX && value >= 0 && dev->rep[code] != value) {
332 0 : dev->rep[code] = value;
333 0 : disposition = INPUT_PASS_TO_ALL;
334 : }
335 : break;
336 :
337 : case EV_FF:
338 0 : if (value >= 0)
339 0 : disposition = INPUT_PASS_TO_ALL;
340 : break;
341 :
342 : case EV_PWR:
343 0 : disposition = INPUT_PASS_TO_ALL;
344 0 : break;
345 : }
346 :
347 0 : *pval = value;
348 0 : return disposition;
349 : }
350 :
351 0 : static void input_event_dispose(struct input_dev *dev, int disposition,
352 : unsigned int type, unsigned int code, int value)
353 : {
354 0 : if ((disposition & INPUT_PASS_TO_DEVICE) && dev->event)
355 0 : dev->event(dev, type, code, value);
356 :
357 0 : if (!dev->vals)
358 : return;
359 :
360 0 : if (disposition & INPUT_PASS_TO_HANDLERS) {
361 : struct input_value *v;
362 :
363 0 : if (disposition & INPUT_SLOT) {
364 0 : v = &dev->vals[dev->num_vals++];
365 0 : v->type = EV_ABS;
366 0 : v->code = ABS_MT_SLOT;
367 0 : v->value = dev->mt->slot;
368 : }
369 :
370 0 : v = &dev->vals[dev->num_vals++];
371 0 : v->type = type;
372 0 : v->code = code;
373 0 : v->value = value;
374 : }
375 :
376 0 : if (disposition & INPUT_FLUSH) {
377 0 : if (dev->num_vals >= 2)
378 0 : input_pass_values(dev, dev->vals, dev->num_vals);
379 0 : dev->num_vals = 0;
380 : /*
381 : * Reset the timestamp on flush so we won't end up
382 : * with a stale one. Note we only need to reset the
383 : * monolithic one as we use its presence when deciding
384 : * whether to generate a synthetic timestamp.
385 : */
386 0 : dev->timestamp[INPUT_CLK_MONO] = ktime_set(0, 0);
387 0 : } else if (dev->num_vals >= dev->max_vals - 2) {
388 0 : dev->vals[dev->num_vals++] = input_value_sync;
389 0 : input_pass_values(dev, dev->vals, dev->num_vals);
390 0 : dev->num_vals = 0;
391 : }
392 : }
393 :
394 0 : void input_handle_event(struct input_dev *dev,
395 : unsigned int type, unsigned int code, int value)
396 : {
397 : int disposition;
398 :
399 : lockdep_assert_held(&dev->event_lock);
400 :
401 0 : disposition = input_get_disposition(dev, type, code, &value);
402 0 : if (disposition != INPUT_IGNORE_EVENT) {
403 0 : if (type != EV_SYN)
404 0 : add_input_randomness(type, code, value);
405 :
406 0 : input_event_dispose(dev, disposition, type, code, value);
407 : }
408 0 : }
409 :
410 : /**
411 : * input_event() - report new input event
412 : * @dev: device that generated the event
413 : * @type: type of the event
414 : * @code: event code
415 : * @value: value of the event
416 : *
417 : * This function should be used by drivers implementing various input
418 : * devices to report input events. See also input_inject_event().
419 : *
420 : * NOTE: input_event() may be safely used right after input device was
421 : * allocated with input_allocate_device(), even before it is registered
422 : * with input_register_device(), but the event will not reach any of the
423 : * input handlers. Such early invocation of input_event() may be used
424 : * to 'seed' initial state of a switch or initial position of absolute
425 : * axis, etc.
426 : */
427 0 : void input_event(struct input_dev *dev,
428 : unsigned int type, unsigned int code, int value)
429 : {
430 : unsigned long flags;
431 :
432 0 : if (is_event_supported(type, dev->evbit, EV_MAX)) {
433 :
434 0 : spin_lock_irqsave(&dev->event_lock, flags);
435 0 : input_handle_event(dev, type, code, value);
436 0 : spin_unlock_irqrestore(&dev->event_lock, flags);
437 : }
438 0 : }
439 : EXPORT_SYMBOL(input_event);
440 :
441 : /**
442 : * input_inject_event() - send input event from input handler
443 : * @handle: input handle to send event through
444 : * @type: type of the event
445 : * @code: event code
446 : * @value: value of the event
447 : *
448 : * Similar to input_event() but will ignore event if device is
449 : * "grabbed" and handle injecting event is not the one that owns
450 : * the device.
451 : */
452 0 : void input_inject_event(struct input_handle *handle,
453 : unsigned int type, unsigned int code, int value)
454 : {
455 0 : struct input_dev *dev = handle->dev;
456 : struct input_handle *grab;
457 : unsigned long flags;
458 :
459 0 : if (is_event_supported(type, dev->evbit, EV_MAX)) {
460 0 : spin_lock_irqsave(&dev->event_lock, flags);
461 :
462 : rcu_read_lock();
463 0 : grab = rcu_dereference(dev->grab);
464 0 : if (!grab || grab == handle)
465 0 : input_handle_event(dev, type, code, value);
466 : rcu_read_unlock();
467 :
468 0 : spin_unlock_irqrestore(&dev->event_lock, flags);
469 : }
470 0 : }
471 : EXPORT_SYMBOL(input_inject_event);
472 :
473 : /**
474 : * input_alloc_absinfo - allocates array of input_absinfo structs
475 : * @dev: the input device emitting absolute events
476 : *
477 : * If the absinfo struct the caller asked for is already allocated, this
478 : * functions will not do anything.
479 : */
480 0 : void input_alloc_absinfo(struct input_dev *dev)
481 : {
482 0 : if (dev->absinfo)
483 : return;
484 :
485 0 : dev->absinfo = kcalloc(ABS_CNT, sizeof(*dev->absinfo), GFP_KERNEL);
486 0 : if (!dev->absinfo) {
487 0 : dev_err(dev->dev.parent ?: &dev->dev,
488 : "%s: unable to allocate memory\n", __func__);
489 : /*
490 : * We will handle this allocation failure in
491 : * input_register_device() when we refuse to register input
492 : * device with ABS bits but without absinfo.
493 : */
494 : }
495 : }
496 : EXPORT_SYMBOL(input_alloc_absinfo);
497 :
498 0 : void input_set_abs_params(struct input_dev *dev, unsigned int axis,
499 : int min, int max, int fuzz, int flat)
500 : {
501 : struct input_absinfo *absinfo;
502 :
503 0 : __set_bit(EV_ABS, dev->evbit);
504 0 : __set_bit(axis, dev->absbit);
505 :
506 0 : input_alloc_absinfo(dev);
507 0 : if (!dev->absinfo)
508 : return;
509 :
510 0 : absinfo = &dev->absinfo[axis];
511 0 : absinfo->minimum = min;
512 0 : absinfo->maximum = max;
513 0 : absinfo->fuzz = fuzz;
514 0 : absinfo->flat = flat;
515 : }
516 : EXPORT_SYMBOL(input_set_abs_params);
517 :
518 : /**
519 : * input_copy_abs - Copy absinfo from one input_dev to another
520 : * @dst: Destination input device to copy the abs settings to
521 : * @dst_axis: ABS_* value selecting the destination axis
522 : * @src: Source input device to copy the abs settings from
523 : * @src_axis: ABS_* value selecting the source axis
524 : *
525 : * Set absinfo for the selected destination axis by copying it from
526 : * the specified source input device's source axis.
527 : * This is useful to e.g. setup a pen/stylus input-device for combined
528 : * touchscreen/pen hardware where the pen uses the same coordinates as
529 : * the touchscreen.
530 : */
531 0 : void input_copy_abs(struct input_dev *dst, unsigned int dst_axis,
532 : const struct input_dev *src, unsigned int src_axis)
533 : {
534 : /* src must have EV_ABS and src_axis set */
535 0 : if (WARN_ON(!(test_bit(EV_ABS, src->evbit) &&
536 : test_bit(src_axis, src->absbit))))
537 : return;
538 :
539 : /*
540 : * input_alloc_absinfo() may have failed for the source. Our caller is
541 : * expected to catch this when registering the input devices, which may
542 : * happen after the input_copy_abs() call.
543 : */
544 0 : if (!src->absinfo)
545 : return;
546 :
547 0 : input_set_capability(dst, EV_ABS, dst_axis);
548 0 : if (!dst->absinfo)
549 : return;
550 :
551 0 : dst->absinfo[dst_axis] = src->absinfo[src_axis];
552 : }
553 : EXPORT_SYMBOL(input_copy_abs);
554 :
555 : /**
556 : * input_grab_device - grabs device for exclusive use
557 : * @handle: input handle that wants to own the device
558 : *
559 : * When a device is grabbed by an input handle all events generated by
560 : * the device are delivered only to this handle. Also events injected
561 : * by other input handles are ignored while device is grabbed.
562 : */
563 0 : int input_grab_device(struct input_handle *handle)
564 : {
565 0 : struct input_dev *dev = handle->dev;
566 : int retval;
567 :
568 0 : retval = mutex_lock_interruptible(&dev->mutex);
569 0 : if (retval)
570 : return retval;
571 :
572 0 : if (dev->grab) {
573 : retval = -EBUSY;
574 : goto out;
575 : }
576 :
577 0 : rcu_assign_pointer(dev->grab, handle);
578 :
579 : out:
580 0 : mutex_unlock(&dev->mutex);
581 0 : return retval;
582 : }
583 : EXPORT_SYMBOL(input_grab_device);
584 :
585 0 : static void __input_release_device(struct input_handle *handle)
586 : {
587 0 : struct input_dev *dev = handle->dev;
588 : struct input_handle *grabber;
589 :
590 0 : grabber = rcu_dereference_protected(dev->grab,
591 : lockdep_is_held(&dev->mutex));
592 0 : if (grabber == handle) {
593 0 : rcu_assign_pointer(dev->grab, NULL);
594 : /* Make sure input_pass_values() notices that grab is gone */
595 0 : synchronize_rcu();
596 :
597 0 : list_for_each_entry(handle, &dev->h_list, d_node)
598 0 : if (handle->open && handle->handler->start)
599 0 : handle->handler->start(handle);
600 : }
601 0 : }
602 :
603 : /**
604 : * input_release_device - release previously grabbed device
605 : * @handle: input handle that owns the device
606 : *
607 : * Releases previously grabbed device so that other input handles can
608 : * start receiving input events. Upon release all handlers attached
609 : * to the device have their start() method called so they have a change
610 : * to synchronize device state with the rest of the system.
611 : */
612 0 : void input_release_device(struct input_handle *handle)
613 : {
614 0 : struct input_dev *dev = handle->dev;
615 :
616 0 : mutex_lock(&dev->mutex);
617 0 : __input_release_device(handle);
618 0 : mutex_unlock(&dev->mutex);
619 0 : }
620 : EXPORT_SYMBOL(input_release_device);
621 :
622 : /**
623 : * input_open_device - open input device
624 : * @handle: handle through which device is being accessed
625 : *
626 : * This function should be called by input handlers when they
627 : * want to start receive events from given input device.
628 : */
629 0 : int input_open_device(struct input_handle *handle)
630 : {
631 0 : struct input_dev *dev = handle->dev;
632 : int retval;
633 :
634 0 : retval = mutex_lock_interruptible(&dev->mutex);
635 0 : if (retval)
636 : return retval;
637 :
638 0 : if (dev->going_away) {
639 : retval = -ENODEV;
640 : goto out;
641 : }
642 :
643 0 : handle->open++;
644 :
645 0 : if (dev->users++ || dev->inhibited) {
646 : /*
647 : * Device is already opened and/or inhibited,
648 : * so we can exit immediately and report success.
649 : */
650 : goto out;
651 : }
652 :
653 0 : if (dev->open) {
654 0 : retval = dev->open(dev);
655 0 : if (retval) {
656 0 : dev->users--;
657 0 : handle->open--;
658 : /*
659 : * Make sure we are not delivering any more events
660 : * through this handle
661 : */
662 0 : synchronize_rcu();
663 0 : goto out;
664 : }
665 : }
666 :
667 0 : if (dev->poller)
668 0 : input_dev_poller_start(dev->poller);
669 :
670 : out:
671 0 : mutex_unlock(&dev->mutex);
672 0 : return retval;
673 : }
674 : EXPORT_SYMBOL(input_open_device);
675 :
676 0 : int input_flush_device(struct input_handle *handle, struct file *file)
677 : {
678 0 : struct input_dev *dev = handle->dev;
679 : int retval;
680 :
681 0 : retval = mutex_lock_interruptible(&dev->mutex);
682 0 : if (retval)
683 : return retval;
684 :
685 0 : if (dev->flush)
686 0 : retval = dev->flush(dev, file);
687 :
688 0 : mutex_unlock(&dev->mutex);
689 0 : return retval;
690 : }
691 : EXPORT_SYMBOL(input_flush_device);
692 :
693 : /**
694 : * input_close_device - close input device
695 : * @handle: handle through which device is being accessed
696 : *
697 : * This function should be called by input handlers when they
698 : * want to stop receive events from given input device.
699 : */
700 0 : void input_close_device(struct input_handle *handle)
701 : {
702 0 : struct input_dev *dev = handle->dev;
703 :
704 0 : mutex_lock(&dev->mutex);
705 :
706 0 : __input_release_device(handle);
707 :
708 0 : if (!--dev->users && !dev->inhibited) {
709 0 : if (dev->poller)
710 0 : input_dev_poller_stop(dev->poller);
711 0 : if (dev->close)
712 0 : dev->close(dev);
713 : }
714 :
715 0 : if (!--handle->open) {
716 : /*
717 : * synchronize_rcu() makes sure that input_pass_values()
718 : * completed and that no more input events are delivered
719 : * through this handle
720 : */
721 0 : synchronize_rcu();
722 : }
723 :
724 0 : mutex_unlock(&dev->mutex);
725 0 : }
726 : EXPORT_SYMBOL(input_close_device);
727 :
728 : /*
729 : * Simulate keyup events for all keys that are marked as pressed.
730 : * The function must be called with dev->event_lock held.
731 : */
732 0 : static bool input_dev_release_keys(struct input_dev *dev)
733 : {
734 0 : bool need_sync = false;
735 : int code;
736 :
737 : lockdep_assert_held(&dev->event_lock);
738 :
739 0 : if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
740 0 : for_each_set_bit(code, dev->key, KEY_CNT) {
741 0 : input_handle_event(dev, EV_KEY, code, 0);
742 0 : need_sync = true;
743 : }
744 : }
745 :
746 0 : return need_sync;
747 : }
748 :
749 : /*
750 : * Prepare device for unregistering
751 : */
752 0 : static void input_disconnect_device(struct input_dev *dev)
753 : {
754 : struct input_handle *handle;
755 :
756 : /*
757 : * Mark device as going away. Note that we take dev->mutex here
758 : * not to protect access to dev->going_away but rather to ensure
759 : * that there are no threads in the middle of input_open_device()
760 : */
761 0 : mutex_lock(&dev->mutex);
762 0 : dev->going_away = true;
763 0 : mutex_unlock(&dev->mutex);
764 :
765 0 : spin_lock_irq(&dev->event_lock);
766 :
767 : /*
768 : * Simulate keyup events for all pressed keys so that handlers
769 : * are not left with "stuck" keys. The driver may continue
770 : * generate events even after we done here but they will not
771 : * reach any handlers.
772 : */
773 0 : if (input_dev_release_keys(dev))
774 0 : input_handle_event(dev, EV_SYN, SYN_REPORT, 1);
775 :
776 0 : list_for_each_entry(handle, &dev->h_list, d_node)
777 0 : handle->open = 0;
778 :
779 0 : spin_unlock_irq(&dev->event_lock);
780 0 : }
781 :
782 : /**
783 : * input_scancode_to_scalar() - converts scancode in &struct input_keymap_entry
784 : * @ke: keymap entry containing scancode to be converted.
785 : * @scancode: pointer to the location where converted scancode should
786 : * be stored.
787 : *
788 : * This function is used to convert scancode stored in &struct keymap_entry
789 : * into scalar form understood by legacy keymap handling methods. These
790 : * methods expect scancodes to be represented as 'unsigned int'.
791 : */
792 0 : int input_scancode_to_scalar(const struct input_keymap_entry *ke,
793 : unsigned int *scancode)
794 : {
795 0 : switch (ke->len) {
796 : case 1:
797 0 : *scancode = *((u8 *)ke->scancode);
798 0 : break;
799 :
800 : case 2:
801 0 : *scancode = *((u16 *)ke->scancode);
802 0 : break;
803 :
804 : case 4:
805 0 : *scancode = *((u32 *)ke->scancode);
806 0 : break;
807 :
808 : default:
809 : return -EINVAL;
810 : }
811 :
812 : return 0;
813 : }
814 : EXPORT_SYMBOL(input_scancode_to_scalar);
815 :
816 : /*
817 : * Those routines handle the default case where no [gs]etkeycode() is
818 : * defined. In this case, an array indexed by the scancode is used.
819 : */
820 :
821 : static unsigned int input_fetch_keycode(struct input_dev *dev,
822 : unsigned int index)
823 : {
824 0 : switch (dev->keycodesize) {
825 : case 1:
826 0 : return ((u8 *)dev->keycode)[index];
827 :
828 : case 2:
829 0 : return ((u16 *)dev->keycode)[index];
830 :
831 : default:
832 0 : return ((u32 *)dev->keycode)[index];
833 : }
834 : }
835 :
836 0 : static int input_default_getkeycode(struct input_dev *dev,
837 : struct input_keymap_entry *ke)
838 : {
839 : unsigned int index;
840 : int error;
841 :
842 0 : if (!dev->keycodesize)
843 : return -EINVAL;
844 :
845 0 : if (ke->flags & INPUT_KEYMAP_BY_INDEX)
846 0 : index = ke->index;
847 : else {
848 0 : error = input_scancode_to_scalar(ke, &index);
849 0 : if (error)
850 : return error;
851 : }
852 :
853 0 : if (index >= dev->keycodemax)
854 : return -EINVAL;
855 :
856 0 : ke->keycode = input_fetch_keycode(dev, index);
857 0 : ke->index = index;
858 0 : ke->len = sizeof(index);
859 0 : memcpy(ke->scancode, &index, sizeof(index));
860 :
861 0 : return 0;
862 : }
863 :
864 0 : static int input_default_setkeycode(struct input_dev *dev,
865 : const struct input_keymap_entry *ke,
866 : unsigned int *old_keycode)
867 : {
868 : unsigned int index;
869 : int error;
870 : int i;
871 :
872 0 : if (!dev->keycodesize)
873 : return -EINVAL;
874 :
875 0 : if (ke->flags & INPUT_KEYMAP_BY_INDEX) {
876 0 : index = ke->index;
877 : } else {
878 0 : error = input_scancode_to_scalar(ke, &index);
879 0 : if (error)
880 : return error;
881 : }
882 :
883 0 : if (index >= dev->keycodemax)
884 : return -EINVAL;
885 :
886 0 : if (dev->keycodesize < sizeof(ke->keycode) &&
887 0 : (ke->keycode >> (dev->keycodesize * 8)))
888 : return -EINVAL;
889 :
890 0 : switch (dev->keycodesize) {
891 : case 1: {
892 0 : u8 *k = (u8 *)dev->keycode;
893 0 : *old_keycode = k[index];
894 0 : k[index] = ke->keycode;
895 0 : break;
896 : }
897 : case 2: {
898 0 : u16 *k = (u16 *)dev->keycode;
899 0 : *old_keycode = k[index];
900 0 : k[index] = ke->keycode;
901 0 : break;
902 : }
903 : default: {
904 0 : u32 *k = (u32 *)dev->keycode;
905 0 : *old_keycode = k[index];
906 0 : k[index] = ke->keycode;
907 0 : break;
908 : }
909 : }
910 :
911 0 : if (*old_keycode <= KEY_MAX) {
912 0 : __clear_bit(*old_keycode, dev->keybit);
913 0 : for (i = 0; i < dev->keycodemax; i++) {
914 0 : if (input_fetch_keycode(dev, i) == *old_keycode) {
915 0 : __set_bit(*old_keycode, dev->keybit);
916 : /* Setting the bit twice is useless, so break */
917 : break;
918 : }
919 : }
920 : }
921 :
922 0 : __set_bit(ke->keycode, dev->keybit);
923 : return 0;
924 : }
925 :
926 : /**
927 : * input_get_keycode - retrieve keycode currently mapped to a given scancode
928 : * @dev: input device which keymap is being queried
929 : * @ke: keymap entry
930 : *
931 : * This function should be called by anyone interested in retrieving current
932 : * keymap. Presently evdev handlers use it.
933 : */
934 0 : int input_get_keycode(struct input_dev *dev, struct input_keymap_entry *ke)
935 : {
936 : unsigned long flags;
937 : int retval;
938 :
939 0 : spin_lock_irqsave(&dev->event_lock, flags);
940 0 : retval = dev->getkeycode(dev, ke);
941 0 : spin_unlock_irqrestore(&dev->event_lock, flags);
942 :
943 0 : return retval;
944 : }
945 : EXPORT_SYMBOL(input_get_keycode);
946 :
947 : /**
948 : * input_set_keycode - attribute a keycode to a given scancode
949 : * @dev: input device which keymap is being updated
950 : * @ke: new keymap entry
951 : *
952 : * This function should be called by anyone needing to update current
953 : * keymap. Presently keyboard and evdev handlers use it.
954 : */
955 0 : int input_set_keycode(struct input_dev *dev,
956 : const struct input_keymap_entry *ke)
957 : {
958 : unsigned long flags;
959 : unsigned int old_keycode;
960 : int retval;
961 :
962 0 : if (ke->keycode > KEY_MAX)
963 : return -EINVAL;
964 :
965 0 : spin_lock_irqsave(&dev->event_lock, flags);
966 :
967 0 : retval = dev->setkeycode(dev, ke, &old_keycode);
968 0 : if (retval)
969 : goto out;
970 :
971 : /* Make sure KEY_RESERVED did not get enabled. */
972 0 : __clear_bit(KEY_RESERVED, dev->keybit);
973 :
974 : /*
975 : * Simulate keyup event if keycode is not present
976 : * in the keymap anymore
977 : */
978 0 : if (old_keycode > KEY_MAX) {
979 0 : dev_warn(dev->dev.parent ?: &dev->dev,
980 : "%s: got too big old keycode %#x\n",
981 : __func__, old_keycode);
982 0 : } else if (test_bit(EV_KEY, dev->evbit) &&
983 0 : !is_event_supported(old_keycode, dev->keybit, KEY_MAX) &&
984 0 : __test_and_clear_bit(old_keycode, dev->key)) {
985 : /*
986 : * We have to use input_event_dispose() here directly instead
987 : * of input_handle_event() because the key we want to release
988 : * here is considered no longer supported by the device and
989 : * input_handle_event() will ignore it.
990 : */
991 0 : input_event_dispose(dev, INPUT_PASS_TO_HANDLERS,
992 : EV_KEY, old_keycode, 0);
993 0 : input_event_dispose(dev, INPUT_PASS_TO_HANDLERS | INPUT_FLUSH,
994 : EV_SYN, SYN_REPORT, 1);
995 : }
996 :
997 : out:
998 0 : spin_unlock_irqrestore(&dev->event_lock, flags);
999 :
1000 0 : return retval;
1001 : }
1002 : EXPORT_SYMBOL(input_set_keycode);
1003 :
1004 0 : bool input_match_device_id(const struct input_dev *dev,
1005 : const struct input_device_id *id)
1006 : {
1007 0 : if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
1008 0 : if (id->bustype != dev->id.bustype)
1009 : return false;
1010 :
1011 0 : if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
1012 0 : if (id->vendor != dev->id.vendor)
1013 : return false;
1014 :
1015 0 : if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
1016 0 : if (id->product != dev->id.product)
1017 : return false;
1018 :
1019 0 : if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
1020 0 : if (id->version != dev->id.version)
1021 : return false;
1022 :
1023 0 : if (!bitmap_subset(id->evbit, dev->evbit, EV_MAX) ||
1024 0 : !bitmap_subset(id->keybit, dev->keybit, KEY_MAX) ||
1025 0 : !bitmap_subset(id->relbit, dev->relbit, REL_MAX) ||
1026 0 : !bitmap_subset(id->absbit, dev->absbit, ABS_MAX) ||
1027 0 : !bitmap_subset(id->mscbit, dev->mscbit, MSC_MAX) ||
1028 0 : !bitmap_subset(id->ledbit, dev->ledbit, LED_MAX) ||
1029 0 : !bitmap_subset(id->sndbit, dev->sndbit, SND_MAX) ||
1030 0 : !bitmap_subset(id->ffbit, dev->ffbit, FF_MAX) ||
1031 0 : !bitmap_subset(id->swbit, dev->swbit, SW_MAX) ||
1032 0 : !bitmap_subset(id->propbit, dev->propbit, INPUT_PROP_MAX)) {
1033 : return false;
1034 : }
1035 :
1036 : return true;
1037 : }
1038 : EXPORT_SYMBOL(input_match_device_id);
1039 :
1040 0 : static const struct input_device_id *input_match_device(struct input_handler *handler,
1041 : struct input_dev *dev)
1042 : {
1043 : const struct input_device_id *id;
1044 :
1045 0 : for (id = handler->id_table; id->flags || id->driver_info; id++) {
1046 0 : if (input_match_device_id(dev, id) &&
1047 0 : (!handler->match || handler->match(handler, dev))) {
1048 : return id;
1049 : }
1050 : }
1051 :
1052 : return NULL;
1053 : }
1054 :
1055 0 : static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
1056 : {
1057 : const struct input_device_id *id;
1058 : int error;
1059 :
1060 0 : id = input_match_device(handler, dev);
1061 0 : if (!id)
1062 : return -ENODEV;
1063 :
1064 0 : error = handler->connect(handler, dev, id);
1065 0 : if (error && error != -ENODEV)
1066 0 : pr_err("failed to attach handler %s to device %s, error: %d\n",
1067 : handler->name, kobject_name(&dev->dev.kobj), error);
1068 :
1069 : return error;
1070 : }
1071 :
1072 : #ifdef CONFIG_COMPAT
1073 :
1074 : static int input_bits_to_string(char *buf, int buf_size,
1075 : unsigned long bits, bool skip_empty)
1076 : {
1077 : int len = 0;
1078 :
1079 : if (in_compat_syscall()) {
1080 : u32 dword = bits >> 32;
1081 : if (dword || !skip_empty)
1082 : len += snprintf(buf, buf_size, "%x ", dword);
1083 :
1084 : dword = bits & 0xffffffffUL;
1085 : if (dword || !skip_empty || len)
1086 : len += snprintf(buf + len, max(buf_size - len, 0),
1087 : "%x", dword);
1088 : } else {
1089 : if (bits || !skip_empty)
1090 : len += snprintf(buf, buf_size, "%lx", bits);
1091 : }
1092 :
1093 : return len;
1094 : }
1095 :
1096 : #else /* !CONFIG_COMPAT */
1097 :
1098 : static int input_bits_to_string(char *buf, int buf_size,
1099 : unsigned long bits, bool skip_empty)
1100 : {
1101 0 : return bits || !skip_empty ?
1102 0 : snprintf(buf, buf_size, "%lx", bits) : 0;
1103 : }
1104 :
1105 : #endif
1106 :
1107 : #ifdef CONFIG_PROC_FS
1108 :
1109 : static struct proc_dir_entry *proc_bus_input_dir;
1110 : static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
1111 : static int input_devices_state;
1112 :
1113 : static inline void input_wakeup_procfs_readers(void)
1114 : {
1115 0 : input_devices_state++;
1116 0 : wake_up(&input_devices_poll_wait);
1117 : }
1118 :
1119 0 : static __poll_t input_proc_devices_poll(struct file *file, poll_table *wait)
1120 : {
1121 0 : poll_wait(file, &input_devices_poll_wait, wait);
1122 0 : if (file->f_version != input_devices_state) {
1123 0 : file->f_version = input_devices_state;
1124 0 : return EPOLLIN | EPOLLRDNORM;
1125 : }
1126 :
1127 : return 0;
1128 : }
1129 :
1130 : union input_seq_state {
1131 : struct {
1132 : unsigned short pos;
1133 : bool mutex_acquired;
1134 : };
1135 : void *p;
1136 : };
1137 :
1138 0 : static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
1139 : {
1140 0 : union input_seq_state *state = (union input_seq_state *)&seq->private;
1141 : int error;
1142 :
1143 : /* We need to fit into seq->private pointer */
1144 : BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1145 :
1146 0 : error = mutex_lock_interruptible(&input_mutex);
1147 0 : if (error) {
1148 0 : state->mutex_acquired = false;
1149 0 : return ERR_PTR(error);
1150 : }
1151 :
1152 0 : state->mutex_acquired = true;
1153 :
1154 0 : return seq_list_start(&input_dev_list, *pos);
1155 : }
1156 :
1157 0 : static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1158 : {
1159 0 : return seq_list_next(v, &input_dev_list, pos);
1160 : }
1161 :
1162 0 : static void input_seq_stop(struct seq_file *seq, void *v)
1163 : {
1164 0 : union input_seq_state *state = (union input_seq_state *)&seq->private;
1165 :
1166 0 : if (state->mutex_acquired)
1167 0 : mutex_unlock(&input_mutex);
1168 0 : }
1169 :
1170 0 : static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
1171 : unsigned long *bitmap, int max)
1172 : {
1173 : int i;
1174 0 : bool skip_empty = true;
1175 : char buf[18];
1176 :
1177 0 : seq_printf(seq, "B: %s=", name);
1178 :
1179 0 : for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1180 0 : if (input_bits_to_string(buf, sizeof(buf),
1181 0 : bitmap[i], skip_empty)) {
1182 0 : skip_empty = false;
1183 0 : seq_printf(seq, "%s%s", buf, i > 0 ? " " : "");
1184 : }
1185 : }
1186 :
1187 : /*
1188 : * If no output was produced print a single 0.
1189 : */
1190 0 : if (skip_empty)
1191 0 : seq_putc(seq, '0');
1192 :
1193 0 : seq_putc(seq, '\n');
1194 0 : }
1195 :
1196 0 : static int input_devices_seq_show(struct seq_file *seq, void *v)
1197 : {
1198 0 : struct input_dev *dev = container_of(v, struct input_dev, node);
1199 0 : const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1200 : struct input_handle *handle;
1201 :
1202 0 : seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
1203 0 : dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
1204 :
1205 0 : seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
1206 0 : seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
1207 0 : seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
1208 0 : seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
1209 0 : seq_puts(seq, "H: Handlers=");
1210 :
1211 0 : list_for_each_entry(handle, &dev->h_list, d_node)
1212 0 : seq_printf(seq, "%s ", handle->name);
1213 0 : seq_putc(seq, '\n');
1214 :
1215 0 : input_seq_print_bitmap(seq, "PROP", dev->propbit, INPUT_PROP_MAX);
1216 :
1217 0 : input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
1218 0 : if (test_bit(EV_KEY, dev->evbit))
1219 0 : input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
1220 0 : if (test_bit(EV_REL, dev->evbit))
1221 0 : input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
1222 0 : if (test_bit(EV_ABS, dev->evbit))
1223 0 : input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
1224 0 : if (test_bit(EV_MSC, dev->evbit))
1225 0 : input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
1226 0 : if (test_bit(EV_LED, dev->evbit))
1227 0 : input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
1228 0 : if (test_bit(EV_SND, dev->evbit))
1229 0 : input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
1230 0 : if (test_bit(EV_FF, dev->evbit))
1231 0 : input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
1232 0 : if (test_bit(EV_SW, dev->evbit))
1233 0 : input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);
1234 :
1235 0 : seq_putc(seq, '\n');
1236 :
1237 0 : kfree(path);
1238 0 : return 0;
1239 : }
1240 :
1241 : static const struct seq_operations input_devices_seq_ops = {
1242 : .start = input_devices_seq_start,
1243 : .next = input_devices_seq_next,
1244 : .stop = input_seq_stop,
1245 : .show = input_devices_seq_show,
1246 : };
1247 :
1248 0 : static int input_proc_devices_open(struct inode *inode, struct file *file)
1249 : {
1250 0 : return seq_open(file, &input_devices_seq_ops);
1251 : }
1252 :
1253 : static const struct proc_ops input_devices_proc_ops = {
1254 : .proc_open = input_proc_devices_open,
1255 : .proc_poll = input_proc_devices_poll,
1256 : .proc_read = seq_read,
1257 : .proc_lseek = seq_lseek,
1258 : .proc_release = seq_release,
1259 : };
1260 :
1261 0 : static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
1262 : {
1263 0 : union input_seq_state *state = (union input_seq_state *)&seq->private;
1264 : int error;
1265 :
1266 : /* We need to fit into seq->private pointer */
1267 : BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1268 :
1269 0 : error = mutex_lock_interruptible(&input_mutex);
1270 0 : if (error) {
1271 0 : state->mutex_acquired = false;
1272 0 : return ERR_PTR(error);
1273 : }
1274 :
1275 0 : state->mutex_acquired = true;
1276 0 : state->pos = *pos;
1277 :
1278 0 : return seq_list_start(&input_handler_list, *pos);
1279 : }
1280 :
1281 0 : static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1282 : {
1283 0 : union input_seq_state *state = (union input_seq_state *)&seq->private;
1284 :
1285 0 : state->pos = *pos + 1;
1286 0 : return seq_list_next(v, &input_handler_list, pos);
1287 : }
1288 :
1289 0 : static int input_handlers_seq_show(struct seq_file *seq, void *v)
1290 : {
1291 0 : struct input_handler *handler = container_of(v, struct input_handler, node);
1292 0 : union input_seq_state *state = (union input_seq_state *)&seq->private;
1293 :
1294 0 : seq_printf(seq, "N: Number=%u Name=%s", state->pos, handler->name);
1295 0 : if (handler->filter)
1296 0 : seq_puts(seq, " (filter)");
1297 0 : if (handler->legacy_minors)
1298 0 : seq_printf(seq, " Minor=%d", handler->minor);
1299 0 : seq_putc(seq, '\n');
1300 :
1301 0 : return 0;
1302 : }
1303 :
1304 : static const struct seq_operations input_handlers_seq_ops = {
1305 : .start = input_handlers_seq_start,
1306 : .next = input_handlers_seq_next,
1307 : .stop = input_seq_stop,
1308 : .show = input_handlers_seq_show,
1309 : };
1310 :
1311 0 : static int input_proc_handlers_open(struct inode *inode, struct file *file)
1312 : {
1313 0 : return seq_open(file, &input_handlers_seq_ops);
1314 : }
1315 :
1316 : static const struct proc_ops input_handlers_proc_ops = {
1317 : .proc_open = input_proc_handlers_open,
1318 : .proc_read = seq_read,
1319 : .proc_lseek = seq_lseek,
1320 : .proc_release = seq_release,
1321 : };
1322 :
1323 1 : static int __init input_proc_init(void)
1324 : {
1325 : struct proc_dir_entry *entry;
1326 :
1327 1 : proc_bus_input_dir = proc_mkdir("bus/input", NULL);
1328 1 : if (!proc_bus_input_dir)
1329 : return -ENOMEM;
1330 :
1331 1 : entry = proc_create("devices", 0, proc_bus_input_dir,
1332 : &input_devices_proc_ops);
1333 1 : if (!entry)
1334 : goto fail1;
1335 :
1336 1 : entry = proc_create("handlers", 0, proc_bus_input_dir,
1337 : &input_handlers_proc_ops);
1338 1 : if (!entry)
1339 : goto fail2;
1340 :
1341 : return 0;
1342 :
1343 0 : fail2: remove_proc_entry("devices", proc_bus_input_dir);
1344 0 : fail1: remove_proc_entry("bus/input", NULL);
1345 0 : return -ENOMEM;
1346 : }
1347 :
1348 0 : static void input_proc_exit(void)
1349 : {
1350 0 : remove_proc_entry("devices", proc_bus_input_dir);
1351 0 : remove_proc_entry("handlers", proc_bus_input_dir);
1352 0 : remove_proc_entry("bus/input", NULL);
1353 0 : }
1354 :
1355 : #else /* !CONFIG_PROC_FS */
1356 : static inline void input_wakeup_procfs_readers(void) { }
1357 : static inline int input_proc_init(void) { return 0; }
1358 : static inline void input_proc_exit(void) { }
1359 : #endif
1360 :
1361 : #define INPUT_DEV_STRING_ATTR_SHOW(name) \
1362 : static ssize_t input_dev_show_##name(struct device *dev, \
1363 : struct device_attribute *attr, \
1364 : char *buf) \
1365 : { \
1366 : struct input_dev *input_dev = to_input_dev(dev); \
1367 : \
1368 : return scnprintf(buf, PAGE_SIZE, "%s\n", \
1369 : input_dev->name ? input_dev->name : ""); \
1370 : } \
1371 : static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
1372 :
1373 0 : INPUT_DEV_STRING_ATTR_SHOW(name);
1374 0 : INPUT_DEV_STRING_ATTR_SHOW(phys);
1375 0 : INPUT_DEV_STRING_ATTR_SHOW(uniq);
1376 :
1377 0 : static int input_print_modalias_bits(char *buf, int size,
1378 : char name, const unsigned long *bm,
1379 : unsigned int min_bit, unsigned int max_bit)
1380 : {
1381 0 : int len = 0, i;
1382 :
1383 0 : len += snprintf(buf, max(size, 0), "%c", name);
1384 0 : for (i = min_bit; i < max_bit; i++)
1385 0 : if (bm[BIT_WORD(i)] & BIT_MASK(i))
1386 0 : len += snprintf(buf + len, max(size - len, 0), "%X,", i);
1387 0 : return len;
1388 : }
1389 :
1390 0 : static int input_print_modalias(char *buf, int size, const struct input_dev *id,
1391 : int add_cr)
1392 : {
1393 : int len;
1394 :
1395 0 : len = snprintf(buf, max(size, 0),
1396 : "input:b%04Xv%04Xp%04Xe%04X-",
1397 0 : id->id.bustype, id->id.vendor,
1398 0 : id->id.product, id->id.version);
1399 :
1400 0 : len += input_print_modalias_bits(buf + len, size - len,
1401 0 : 'e', id->evbit, 0, EV_MAX);
1402 0 : len += input_print_modalias_bits(buf + len, size - len,
1403 0 : 'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
1404 0 : len += input_print_modalias_bits(buf + len, size - len,
1405 0 : 'r', id->relbit, 0, REL_MAX);
1406 0 : len += input_print_modalias_bits(buf + len, size - len,
1407 0 : 'a', id->absbit, 0, ABS_MAX);
1408 0 : len += input_print_modalias_bits(buf + len, size - len,
1409 0 : 'm', id->mscbit, 0, MSC_MAX);
1410 0 : len += input_print_modalias_bits(buf + len, size - len,
1411 0 : 'l', id->ledbit, 0, LED_MAX);
1412 0 : len += input_print_modalias_bits(buf + len, size - len,
1413 0 : 's', id->sndbit, 0, SND_MAX);
1414 0 : len += input_print_modalias_bits(buf + len, size - len,
1415 0 : 'f', id->ffbit, 0, FF_MAX);
1416 0 : len += input_print_modalias_bits(buf + len, size - len,
1417 0 : 'w', id->swbit, 0, SW_MAX);
1418 :
1419 0 : if (add_cr)
1420 0 : len += snprintf(buf + len, max(size - len, 0), "\n");
1421 :
1422 0 : return len;
1423 : }
1424 :
1425 0 : static ssize_t input_dev_show_modalias(struct device *dev,
1426 : struct device_attribute *attr,
1427 : char *buf)
1428 : {
1429 0 : struct input_dev *id = to_input_dev(dev);
1430 : ssize_t len;
1431 :
1432 0 : len = input_print_modalias(buf, PAGE_SIZE, id, 1);
1433 :
1434 0 : return min_t(int, len, PAGE_SIZE);
1435 : }
1436 : static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
1437 :
1438 : static int input_print_bitmap(char *buf, int buf_size, const unsigned long *bitmap,
1439 : int max, int add_cr);
1440 :
1441 0 : static ssize_t input_dev_show_properties(struct device *dev,
1442 : struct device_attribute *attr,
1443 : char *buf)
1444 : {
1445 0 : struct input_dev *input_dev = to_input_dev(dev);
1446 0 : int len = input_print_bitmap(buf, PAGE_SIZE, input_dev->propbit,
1447 : INPUT_PROP_MAX, true);
1448 0 : return min_t(int, len, PAGE_SIZE);
1449 : }
1450 : static DEVICE_ATTR(properties, S_IRUGO, input_dev_show_properties, NULL);
1451 :
1452 : static int input_inhibit_device(struct input_dev *dev);
1453 : static int input_uninhibit_device(struct input_dev *dev);
1454 :
1455 0 : static ssize_t inhibited_show(struct device *dev,
1456 : struct device_attribute *attr,
1457 : char *buf)
1458 : {
1459 0 : struct input_dev *input_dev = to_input_dev(dev);
1460 :
1461 0 : return scnprintf(buf, PAGE_SIZE, "%d\n", input_dev->inhibited);
1462 : }
1463 :
1464 0 : static ssize_t inhibited_store(struct device *dev,
1465 : struct device_attribute *attr, const char *buf,
1466 : size_t len)
1467 : {
1468 0 : struct input_dev *input_dev = to_input_dev(dev);
1469 : ssize_t rv;
1470 : bool inhibited;
1471 :
1472 0 : if (kstrtobool(buf, &inhibited))
1473 : return -EINVAL;
1474 :
1475 0 : if (inhibited)
1476 0 : rv = input_inhibit_device(input_dev);
1477 : else
1478 0 : rv = input_uninhibit_device(input_dev);
1479 :
1480 0 : if (rv != 0)
1481 : return rv;
1482 :
1483 0 : return len;
1484 : }
1485 :
1486 : static DEVICE_ATTR_RW(inhibited);
1487 :
1488 : static struct attribute *input_dev_attrs[] = {
1489 : &dev_attr_name.attr,
1490 : &dev_attr_phys.attr,
1491 : &dev_attr_uniq.attr,
1492 : &dev_attr_modalias.attr,
1493 : &dev_attr_properties.attr,
1494 : &dev_attr_inhibited.attr,
1495 : NULL
1496 : };
1497 :
1498 : static const struct attribute_group input_dev_attr_group = {
1499 : .attrs = input_dev_attrs,
1500 : };
1501 :
1502 : #define INPUT_DEV_ID_ATTR(name) \
1503 : static ssize_t input_dev_show_id_##name(struct device *dev, \
1504 : struct device_attribute *attr, \
1505 : char *buf) \
1506 : { \
1507 : struct input_dev *input_dev = to_input_dev(dev); \
1508 : return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name); \
1509 : } \
1510 : static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
1511 :
1512 0 : INPUT_DEV_ID_ATTR(bustype);
1513 0 : INPUT_DEV_ID_ATTR(vendor);
1514 0 : INPUT_DEV_ID_ATTR(product);
1515 0 : INPUT_DEV_ID_ATTR(version);
1516 :
1517 : static struct attribute *input_dev_id_attrs[] = {
1518 : &dev_attr_bustype.attr,
1519 : &dev_attr_vendor.attr,
1520 : &dev_attr_product.attr,
1521 : &dev_attr_version.attr,
1522 : NULL
1523 : };
1524 :
1525 : static const struct attribute_group input_dev_id_attr_group = {
1526 : .name = "id",
1527 : .attrs = input_dev_id_attrs,
1528 : };
1529 :
1530 0 : static int input_print_bitmap(char *buf, int buf_size, const unsigned long *bitmap,
1531 : int max, int add_cr)
1532 : {
1533 : int i;
1534 0 : int len = 0;
1535 0 : bool skip_empty = true;
1536 :
1537 0 : for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1538 0 : len += input_bits_to_string(buf + len, max(buf_size - len, 0),
1539 0 : bitmap[i], skip_empty);
1540 0 : if (len) {
1541 0 : skip_empty = false;
1542 0 : if (i > 0)
1543 0 : len += snprintf(buf + len, max(buf_size - len, 0), " ");
1544 : }
1545 : }
1546 :
1547 : /*
1548 : * If no output was produced print a single 0.
1549 : */
1550 0 : if (len == 0)
1551 0 : len = snprintf(buf, buf_size, "%d", 0);
1552 :
1553 0 : if (add_cr)
1554 0 : len += snprintf(buf + len, max(buf_size - len, 0), "\n");
1555 :
1556 0 : return len;
1557 : }
1558 :
1559 : #define INPUT_DEV_CAP_ATTR(ev, bm) \
1560 : static ssize_t input_dev_show_cap_##bm(struct device *dev, \
1561 : struct device_attribute *attr, \
1562 : char *buf) \
1563 : { \
1564 : struct input_dev *input_dev = to_input_dev(dev); \
1565 : int len = input_print_bitmap(buf, PAGE_SIZE, \
1566 : input_dev->bm##bit, ev##_MAX, \
1567 : true); \
1568 : return min_t(int, len, PAGE_SIZE); \
1569 : } \
1570 : static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
1571 :
1572 0 : INPUT_DEV_CAP_ATTR(EV, ev);
1573 0 : INPUT_DEV_CAP_ATTR(KEY, key);
1574 0 : INPUT_DEV_CAP_ATTR(REL, rel);
1575 0 : INPUT_DEV_CAP_ATTR(ABS, abs);
1576 0 : INPUT_DEV_CAP_ATTR(MSC, msc);
1577 0 : INPUT_DEV_CAP_ATTR(LED, led);
1578 0 : INPUT_DEV_CAP_ATTR(SND, snd);
1579 0 : INPUT_DEV_CAP_ATTR(FF, ff);
1580 0 : INPUT_DEV_CAP_ATTR(SW, sw);
1581 :
1582 : static struct attribute *input_dev_caps_attrs[] = {
1583 : &dev_attr_ev.attr,
1584 : &dev_attr_key.attr,
1585 : &dev_attr_rel.attr,
1586 : &dev_attr_abs.attr,
1587 : &dev_attr_msc.attr,
1588 : &dev_attr_led.attr,
1589 : &dev_attr_snd.attr,
1590 : &dev_attr_ff.attr,
1591 : &dev_attr_sw.attr,
1592 : NULL
1593 : };
1594 :
1595 : static const struct attribute_group input_dev_caps_attr_group = {
1596 : .name = "capabilities",
1597 : .attrs = input_dev_caps_attrs,
1598 : };
1599 :
1600 : static const struct attribute_group *input_dev_attr_groups[] = {
1601 : &input_dev_attr_group,
1602 : &input_dev_id_attr_group,
1603 : &input_dev_caps_attr_group,
1604 : &input_poller_attribute_group,
1605 : NULL
1606 : };
1607 :
1608 0 : static void input_dev_release(struct device *device)
1609 : {
1610 0 : struct input_dev *dev = to_input_dev(device);
1611 :
1612 0 : input_ff_destroy(dev);
1613 0 : input_mt_destroy_slots(dev);
1614 0 : kfree(dev->poller);
1615 0 : kfree(dev->absinfo);
1616 0 : kfree(dev->vals);
1617 0 : kfree(dev);
1618 :
1619 0 : module_put(THIS_MODULE);
1620 0 : }
1621 :
1622 : /*
1623 : * Input uevent interface - loading event handlers based on
1624 : * device bitfields.
1625 : */
1626 0 : static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
1627 : const char *name, const unsigned long *bitmap, int max)
1628 : {
1629 : int len;
1630 :
1631 0 : if (add_uevent_var(env, "%s", name))
1632 : return -ENOMEM;
1633 :
1634 0 : len = input_print_bitmap(&env->buf[env->buflen - 1],
1635 0 : sizeof(env->buf) - env->buflen,
1636 : bitmap, max, false);
1637 0 : if (len >= (sizeof(env->buf) - env->buflen))
1638 : return -ENOMEM;
1639 :
1640 0 : env->buflen += len;
1641 0 : return 0;
1642 : }
1643 :
1644 0 : static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
1645 : const struct input_dev *dev)
1646 : {
1647 : int len;
1648 :
1649 0 : if (add_uevent_var(env, "MODALIAS="))
1650 : return -ENOMEM;
1651 :
1652 0 : len = input_print_modalias(&env->buf[env->buflen - 1],
1653 0 : sizeof(env->buf) - env->buflen,
1654 : dev, 0);
1655 0 : if (len >= (sizeof(env->buf) - env->buflen))
1656 : return -ENOMEM;
1657 :
1658 0 : env->buflen += len;
1659 0 : return 0;
1660 : }
1661 :
1662 : #define INPUT_ADD_HOTPLUG_VAR(fmt, val...) \
1663 : do { \
1664 : int err = add_uevent_var(env, fmt, val); \
1665 : if (err) \
1666 : return err; \
1667 : } while (0)
1668 :
1669 : #define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max) \
1670 : do { \
1671 : int err = input_add_uevent_bm_var(env, name, bm, max); \
1672 : if (err) \
1673 : return err; \
1674 : } while (0)
1675 :
1676 : #define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev) \
1677 : do { \
1678 : int err = input_add_uevent_modalias_var(env, dev); \
1679 : if (err) \
1680 : return err; \
1681 : } while (0)
1682 :
1683 0 : static int input_dev_uevent(const struct device *device, struct kobj_uevent_env *env)
1684 : {
1685 0 : const struct input_dev *dev = to_input_dev(device);
1686 :
1687 0 : INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
1688 : dev->id.bustype, dev->id.vendor,
1689 : dev->id.product, dev->id.version);
1690 0 : if (dev->name)
1691 0 : INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
1692 0 : if (dev->phys)
1693 0 : INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
1694 0 : if (dev->uniq)
1695 0 : INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
1696 :
1697 0 : INPUT_ADD_HOTPLUG_BM_VAR("PROP=", dev->propbit, INPUT_PROP_MAX);
1698 :
1699 0 : INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
1700 0 : if (test_bit(EV_KEY, dev->evbit))
1701 0 : INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
1702 0 : if (test_bit(EV_REL, dev->evbit))
1703 0 : INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
1704 0 : if (test_bit(EV_ABS, dev->evbit))
1705 0 : INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
1706 0 : if (test_bit(EV_MSC, dev->evbit))
1707 0 : INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
1708 0 : if (test_bit(EV_LED, dev->evbit))
1709 0 : INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
1710 0 : if (test_bit(EV_SND, dev->evbit))
1711 0 : INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
1712 0 : if (test_bit(EV_FF, dev->evbit))
1713 0 : INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
1714 0 : if (test_bit(EV_SW, dev->evbit))
1715 0 : INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
1716 :
1717 0 : INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
1718 :
1719 0 : return 0;
1720 : }
1721 :
1722 : #define INPUT_DO_TOGGLE(dev, type, bits, on) \
1723 : do { \
1724 : int i; \
1725 : bool active; \
1726 : \
1727 : if (!test_bit(EV_##type, dev->evbit)) \
1728 : break; \
1729 : \
1730 : for_each_set_bit(i, dev->bits##bit, type##_CNT) { \
1731 : active = test_bit(i, dev->bits); \
1732 : if (!active && !on) \
1733 : continue; \
1734 : \
1735 : dev->event(dev, EV_##type, i, on ? active : 0); \
1736 : } \
1737 : } while (0)
1738 :
1739 0 : static void input_dev_toggle(struct input_dev *dev, bool activate)
1740 : {
1741 0 : if (!dev->event)
1742 : return;
1743 :
1744 0 : INPUT_DO_TOGGLE(dev, LED, led, activate);
1745 0 : INPUT_DO_TOGGLE(dev, SND, snd, activate);
1746 :
1747 0 : if (activate && test_bit(EV_REP, dev->evbit)) {
1748 0 : dev->event(dev, EV_REP, REP_PERIOD, dev->rep[REP_PERIOD]);
1749 0 : dev->event(dev, EV_REP, REP_DELAY, dev->rep[REP_DELAY]);
1750 : }
1751 : }
1752 :
1753 : /**
1754 : * input_reset_device() - reset/restore the state of input device
1755 : * @dev: input device whose state needs to be reset
1756 : *
1757 : * This function tries to reset the state of an opened input device and
1758 : * bring internal state and state if the hardware in sync with each other.
1759 : * We mark all keys as released, restore LED state, repeat rate, etc.
1760 : */
1761 0 : void input_reset_device(struct input_dev *dev)
1762 : {
1763 : unsigned long flags;
1764 :
1765 0 : mutex_lock(&dev->mutex);
1766 0 : spin_lock_irqsave(&dev->event_lock, flags);
1767 :
1768 0 : input_dev_toggle(dev, true);
1769 0 : if (input_dev_release_keys(dev))
1770 0 : input_handle_event(dev, EV_SYN, SYN_REPORT, 1);
1771 :
1772 0 : spin_unlock_irqrestore(&dev->event_lock, flags);
1773 0 : mutex_unlock(&dev->mutex);
1774 0 : }
1775 : EXPORT_SYMBOL(input_reset_device);
1776 :
1777 0 : static int input_inhibit_device(struct input_dev *dev)
1778 : {
1779 0 : mutex_lock(&dev->mutex);
1780 :
1781 0 : if (dev->inhibited)
1782 : goto out;
1783 :
1784 0 : if (dev->users) {
1785 0 : if (dev->close)
1786 0 : dev->close(dev);
1787 0 : if (dev->poller)
1788 0 : input_dev_poller_stop(dev->poller);
1789 : }
1790 :
1791 0 : spin_lock_irq(&dev->event_lock);
1792 0 : input_mt_release_slots(dev);
1793 0 : input_dev_release_keys(dev);
1794 0 : input_handle_event(dev, EV_SYN, SYN_REPORT, 1);
1795 0 : input_dev_toggle(dev, false);
1796 0 : spin_unlock_irq(&dev->event_lock);
1797 :
1798 0 : dev->inhibited = true;
1799 :
1800 : out:
1801 0 : mutex_unlock(&dev->mutex);
1802 0 : return 0;
1803 : }
1804 :
1805 0 : static int input_uninhibit_device(struct input_dev *dev)
1806 : {
1807 0 : int ret = 0;
1808 :
1809 0 : mutex_lock(&dev->mutex);
1810 :
1811 0 : if (!dev->inhibited)
1812 : goto out;
1813 :
1814 0 : if (dev->users) {
1815 0 : if (dev->open) {
1816 0 : ret = dev->open(dev);
1817 0 : if (ret)
1818 : goto out;
1819 : }
1820 0 : if (dev->poller)
1821 0 : input_dev_poller_start(dev->poller);
1822 : }
1823 :
1824 0 : dev->inhibited = false;
1825 0 : spin_lock_irq(&dev->event_lock);
1826 0 : input_dev_toggle(dev, true);
1827 0 : spin_unlock_irq(&dev->event_lock);
1828 :
1829 : out:
1830 0 : mutex_unlock(&dev->mutex);
1831 0 : return ret;
1832 : }
1833 :
1834 0 : static int input_dev_suspend(struct device *dev)
1835 : {
1836 0 : struct input_dev *input_dev = to_input_dev(dev);
1837 :
1838 0 : spin_lock_irq(&input_dev->event_lock);
1839 :
1840 : /*
1841 : * Keys that are pressed now are unlikely to be
1842 : * still pressed when we resume.
1843 : */
1844 0 : if (input_dev_release_keys(input_dev))
1845 0 : input_handle_event(input_dev, EV_SYN, SYN_REPORT, 1);
1846 :
1847 : /* Turn off LEDs and sounds, if any are active. */
1848 0 : input_dev_toggle(input_dev, false);
1849 :
1850 0 : spin_unlock_irq(&input_dev->event_lock);
1851 :
1852 0 : return 0;
1853 : }
1854 :
1855 0 : static int input_dev_resume(struct device *dev)
1856 : {
1857 0 : struct input_dev *input_dev = to_input_dev(dev);
1858 :
1859 0 : spin_lock_irq(&input_dev->event_lock);
1860 :
1861 : /* Restore state of LEDs and sounds, if any were active. */
1862 0 : input_dev_toggle(input_dev, true);
1863 :
1864 0 : spin_unlock_irq(&input_dev->event_lock);
1865 :
1866 0 : return 0;
1867 : }
1868 :
1869 0 : static int input_dev_freeze(struct device *dev)
1870 : {
1871 0 : struct input_dev *input_dev = to_input_dev(dev);
1872 :
1873 0 : spin_lock_irq(&input_dev->event_lock);
1874 :
1875 : /*
1876 : * Keys that are pressed now are unlikely to be
1877 : * still pressed when we resume.
1878 : */
1879 0 : if (input_dev_release_keys(input_dev))
1880 0 : input_handle_event(input_dev, EV_SYN, SYN_REPORT, 1);
1881 :
1882 0 : spin_unlock_irq(&input_dev->event_lock);
1883 :
1884 0 : return 0;
1885 : }
1886 :
1887 0 : static int input_dev_poweroff(struct device *dev)
1888 : {
1889 0 : struct input_dev *input_dev = to_input_dev(dev);
1890 :
1891 0 : spin_lock_irq(&input_dev->event_lock);
1892 :
1893 : /* Turn off LEDs and sounds, if any are active. */
1894 0 : input_dev_toggle(input_dev, false);
1895 :
1896 0 : spin_unlock_irq(&input_dev->event_lock);
1897 :
1898 0 : return 0;
1899 : }
1900 :
1901 : static const struct dev_pm_ops input_dev_pm_ops = {
1902 : .suspend = input_dev_suspend,
1903 : .resume = input_dev_resume,
1904 : .freeze = input_dev_freeze,
1905 : .poweroff = input_dev_poweroff,
1906 : .restore = input_dev_resume,
1907 : };
1908 :
1909 : static const struct device_type input_dev_type = {
1910 : .groups = input_dev_attr_groups,
1911 : .release = input_dev_release,
1912 : .uevent = input_dev_uevent,
1913 : .pm = pm_sleep_ptr(&input_dev_pm_ops),
1914 : };
1915 :
1916 0 : static char *input_devnode(const struct device *dev, umode_t *mode)
1917 : {
1918 0 : return kasprintf(GFP_KERNEL, "input/%s", dev_name(dev));
1919 : }
1920 :
1921 : struct class input_class = {
1922 : .name = "input",
1923 : .devnode = input_devnode,
1924 : };
1925 : EXPORT_SYMBOL_GPL(input_class);
1926 :
1927 : /**
1928 : * input_allocate_device - allocate memory for new input device
1929 : *
1930 : * Returns prepared struct input_dev or %NULL.
1931 : *
1932 : * NOTE: Use input_free_device() to free devices that have not been
1933 : * registered; input_unregister_device() should be used for already
1934 : * registered devices.
1935 : */
1936 0 : struct input_dev *input_allocate_device(void)
1937 : {
1938 : static atomic_t input_no = ATOMIC_INIT(-1);
1939 : struct input_dev *dev;
1940 :
1941 0 : dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1942 0 : if (dev) {
1943 0 : dev->dev.type = &input_dev_type;
1944 0 : dev->dev.class = &input_class;
1945 0 : device_initialize(&dev->dev);
1946 0 : mutex_init(&dev->mutex);
1947 0 : spin_lock_init(&dev->event_lock);
1948 0 : timer_setup(&dev->timer, NULL, 0);
1949 0 : INIT_LIST_HEAD(&dev->h_list);
1950 0 : INIT_LIST_HEAD(&dev->node);
1951 :
1952 0 : dev_set_name(&dev->dev, "input%lu",
1953 0 : (unsigned long)atomic_inc_return(&input_no));
1954 :
1955 0 : __module_get(THIS_MODULE);
1956 : }
1957 :
1958 0 : return dev;
1959 : }
1960 : EXPORT_SYMBOL(input_allocate_device);
1961 :
1962 : struct input_devres {
1963 : struct input_dev *input;
1964 : };
1965 :
1966 0 : static int devm_input_device_match(struct device *dev, void *res, void *data)
1967 : {
1968 0 : struct input_devres *devres = res;
1969 :
1970 0 : return devres->input == data;
1971 : }
1972 :
1973 0 : static void devm_input_device_release(struct device *dev, void *res)
1974 : {
1975 0 : struct input_devres *devres = res;
1976 0 : struct input_dev *input = devres->input;
1977 :
1978 : dev_dbg(dev, "%s: dropping reference to %s\n",
1979 : __func__, dev_name(&input->dev));
1980 0 : input_put_device(input);
1981 0 : }
1982 :
1983 : /**
1984 : * devm_input_allocate_device - allocate managed input device
1985 : * @dev: device owning the input device being created
1986 : *
1987 : * Returns prepared struct input_dev or %NULL.
1988 : *
1989 : * Managed input devices do not need to be explicitly unregistered or
1990 : * freed as it will be done automatically when owner device unbinds from
1991 : * its driver (or binding fails). Once managed input device is allocated,
1992 : * it is ready to be set up and registered in the same fashion as regular
1993 : * input device. There are no special devm_input_device_[un]register()
1994 : * variants, regular ones work with both managed and unmanaged devices,
1995 : * should you need them. In most cases however, managed input device need
1996 : * not be explicitly unregistered or freed.
1997 : *
1998 : * NOTE: the owner device is set up as parent of input device and users
1999 : * should not override it.
2000 : */
2001 0 : struct input_dev *devm_input_allocate_device(struct device *dev)
2002 : {
2003 : struct input_dev *input;
2004 : struct input_devres *devres;
2005 :
2006 0 : devres = devres_alloc(devm_input_device_release,
2007 : sizeof(*devres), GFP_KERNEL);
2008 0 : if (!devres)
2009 : return NULL;
2010 :
2011 0 : input = input_allocate_device();
2012 0 : if (!input) {
2013 0 : devres_free(devres);
2014 0 : return NULL;
2015 : }
2016 :
2017 0 : input->dev.parent = dev;
2018 0 : input->devres_managed = true;
2019 :
2020 0 : devres->input = input;
2021 0 : devres_add(dev, devres);
2022 :
2023 0 : return input;
2024 : }
2025 : EXPORT_SYMBOL(devm_input_allocate_device);
2026 :
2027 : /**
2028 : * input_free_device - free memory occupied by input_dev structure
2029 : * @dev: input device to free
2030 : *
2031 : * This function should only be used if input_register_device()
2032 : * was not called yet or if it failed. Once device was registered
2033 : * use input_unregister_device() and memory will be freed once last
2034 : * reference to the device is dropped.
2035 : *
2036 : * Device should be allocated by input_allocate_device().
2037 : *
2038 : * NOTE: If there are references to the input device then memory
2039 : * will not be freed until last reference is dropped.
2040 : */
2041 0 : void input_free_device(struct input_dev *dev)
2042 : {
2043 0 : if (dev) {
2044 0 : if (dev->devres_managed)
2045 0 : WARN_ON(devres_destroy(dev->dev.parent,
2046 : devm_input_device_release,
2047 : devm_input_device_match,
2048 : dev));
2049 : input_put_device(dev);
2050 : }
2051 0 : }
2052 : EXPORT_SYMBOL(input_free_device);
2053 :
2054 : /**
2055 : * input_set_timestamp - set timestamp for input events
2056 : * @dev: input device to set timestamp for
2057 : * @timestamp: the time at which the event has occurred
2058 : * in CLOCK_MONOTONIC
2059 : *
2060 : * This function is intended to provide to the input system a more
2061 : * accurate time of when an event actually occurred. The driver should
2062 : * call this function as soon as a timestamp is acquired ensuring
2063 : * clock conversions in input_set_timestamp are done correctly.
2064 : *
2065 : * The system entering suspend state between timestamp acquisition and
2066 : * calling input_set_timestamp can result in inaccurate conversions.
2067 : */
2068 0 : void input_set_timestamp(struct input_dev *dev, ktime_t timestamp)
2069 : {
2070 0 : dev->timestamp[INPUT_CLK_MONO] = timestamp;
2071 0 : dev->timestamp[INPUT_CLK_REAL] = ktime_mono_to_real(timestamp);
2072 0 : dev->timestamp[INPUT_CLK_BOOT] = ktime_mono_to_any(timestamp,
2073 : TK_OFFS_BOOT);
2074 0 : }
2075 : EXPORT_SYMBOL(input_set_timestamp);
2076 :
2077 : /**
2078 : * input_get_timestamp - get timestamp for input events
2079 : * @dev: input device to get timestamp from
2080 : *
2081 : * A valid timestamp is a timestamp of non-zero value.
2082 : */
2083 0 : ktime_t *input_get_timestamp(struct input_dev *dev)
2084 : {
2085 0 : const ktime_t invalid_timestamp = ktime_set(0, 0);
2086 :
2087 0 : if (!ktime_compare(dev->timestamp[INPUT_CLK_MONO], invalid_timestamp))
2088 0 : input_set_timestamp(dev, ktime_get());
2089 :
2090 0 : return dev->timestamp;
2091 : }
2092 : EXPORT_SYMBOL(input_get_timestamp);
2093 :
2094 : /**
2095 : * input_set_capability - mark device as capable of a certain event
2096 : * @dev: device that is capable of emitting or accepting event
2097 : * @type: type of the event (EV_KEY, EV_REL, etc...)
2098 : * @code: event code
2099 : *
2100 : * In addition to setting up corresponding bit in appropriate capability
2101 : * bitmap the function also adjusts dev->evbit.
2102 : */
2103 0 : void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
2104 : {
2105 0 : if (type < EV_CNT && input_max_code[type] &&
2106 : code > input_max_code[type]) {
2107 0 : pr_err("%s: invalid code %u for type %u\n", __func__, code,
2108 : type);
2109 0 : dump_stack();
2110 0 : return;
2111 : }
2112 :
2113 0 : switch (type) {
2114 : case EV_KEY:
2115 0 : __set_bit(code, dev->keybit);
2116 : break;
2117 :
2118 : case EV_REL:
2119 0 : __set_bit(code, dev->relbit);
2120 : break;
2121 :
2122 : case EV_ABS:
2123 0 : input_alloc_absinfo(dev);
2124 0 : __set_bit(code, dev->absbit);
2125 : break;
2126 :
2127 : case EV_MSC:
2128 0 : __set_bit(code, dev->mscbit);
2129 : break;
2130 :
2131 : case EV_SW:
2132 0 : __set_bit(code, dev->swbit);
2133 : break;
2134 :
2135 : case EV_LED:
2136 0 : __set_bit(code, dev->ledbit);
2137 : break;
2138 :
2139 : case EV_SND:
2140 0 : __set_bit(code, dev->sndbit);
2141 : break;
2142 :
2143 : case EV_FF:
2144 0 : __set_bit(code, dev->ffbit);
2145 : break;
2146 :
2147 : case EV_PWR:
2148 : /* do nothing */
2149 : break;
2150 :
2151 : default:
2152 0 : pr_err("%s: unknown type %u (code %u)\n", __func__, type, code);
2153 0 : dump_stack();
2154 0 : return;
2155 : }
2156 :
2157 0 : __set_bit(type, dev->evbit);
2158 : }
2159 : EXPORT_SYMBOL(input_set_capability);
2160 :
2161 0 : static unsigned int input_estimate_events_per_packet(struct input_dev *dev)
2162 : {
2163 : int mt_slots;
2164 : int i;
2165 : unsigned int events;
2166 :
2167 0 : if (dev->mt) {
2168 0 : mt_slots = dev->mt->num_slots;
2169 0 : } else if (test_bit(ABS_MT_TRACKING_ID, dev->absbit)) {
2170 0 : mt_slots = dev->absinfo[ABS_MT_TRACKING_ID].maximum -
2171 0 : dev->absinfo[ABS_MT_TRACKING_ID].minimum + 1,
2172 0 : mt_slots = clamp(mt_slots, 2, 32);
2173 0 : } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
2174 : mt_slots = 2;
2175 : } else {
2176 0 : mt_slots = 0;
2177 : }
2178 :
2179 0 : events = mt_slots + 1; /* count SYN_MT_REPORT and SYN_REPORT */
2180 :
2181 0 : if (test_bit(EV_ABS, dev->evbit))
2182 0 : for_each_set_bit(i, dev->absbit, ABS_CNT)
2183 0 : events += input_is_mt_axis(i) ? mt_slots : 1;
2184 :
2185 0 : if (test_bit(EV_REL, dev->evbit))
2186 0 : events += bitmap_weight(dev->relbit, REL_CNT);
2187 :
2188 : /* Make room for KEY and MSC events */
2189 0 : events += 7;
2190 :
2191 0 : return events;
2192 : }
2193 :
2194 : #define INPUT_CLEANSE_BITMASK(dev, type, bits) \
2195 : do { \
2196 : if (!test_bit(EV_##type, dev->evbit)) \
2197 : memset(dev->bits##bit, 0, \
2198 : sizeof(dev->bits##bit)); \
2199 : } while (0)
2200 :
2201 0 : static void input_cleanse_bitmasks(struct input_dev *dev)
2202 : {
2203 0 : INPUT_CLEANSE_BITMASK(dev, KEY, key);
2204 0 : INPUT_CLEANSE_BITMASK(dev, REL, rel);
2205 0 : INPUT_CLEANSE_BITMASK(dev, ABS, abs);
2206 0 : INPUT_CLEANSE_BITMASK(dev, MSC, msc);
2207 0 : INPUT_CLEANSE_BITMASK(dev, LED, led);
2208 0 : INPUT_CLEANSE_BITMASK(dev, SND, snd);
2209 0 : INPUT_CLEANSE_BITMASK(dev, FF, ff);
2210 0 : INPUT_CLEANSE_BITMASK(dev, SW, sw);
2211 0 : }
2212 :
2213 0 : static void __input_unregister_device(struct input_dev *dev)
2214 : {
2215 : struct input_handle *handle, *next;
2216 :
2217 0 : input_disconnect_device(dev);
2218 :
2219 0 : mutex_lock(&input_mutex);
2220 :
2221 0 : list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
2222 0 : handle->handler->disconnect(handle);
2223 0 : WARN_ON(!list_empty(&dev->h_list));
2224 :
2225 0 : del_timer_sync(&dev->timer);
2226 0 : list_del_init(&dev->node);
2227 :
2228 : input_wakeup_procfs_readers();
2229 :
2230 0 : mutex_unlock(&input_mutex);
2231 :
2232 0 : device_del(&dev->dev);
2233 0 : }
2234 :
2235 0 : static void devm_input_device_unregister(struct device *dev, void *res)
2236 : {
2237 0 : struct input_devres *devres = res;
2238 0 : struct input_dev *input = devres->input;
2239 :
2240 : dev_dbg(dev, "%s: unregistering device %s\n",
2241 : __func__, dev_name(&input->dev));
2242 0 : __input_unregister_device(input);
2243 0 : }
2244 :
2245 : /*
2246 : * Generate software autorepeat event. Note that we take
2247 : * dev->event_lock here to avoid racing with input_event
2248 : * which may cause keys get "stuck".
2249 : */
2250 0 : static void input_repeat_key(struct timer_list *t)
2251 : {
2252 0 : struct input_dev *dev = from_timer(dev, t, timer);
2253 : unsigned long flags;
2254 :
2255 0 : spin_lock_irqsave(&dev->event_lock, flags);
2256 :
2257 0 : if (!dev->inhibited &&
2258 0 : test_bit(dev->repeat_key, dev->key) &&
2259 0 : is_event_supported(dev->repeat_key, dev->keybit, KEY_MAX)) {
2260 :
2261 0 : input_set_timestamp(dev, ktime_get());
2262 0 : input_handle_event(dev, EV_KEY, dev->repeat_key, 2);
2263 0 : input_handle_event(dev, EV_SYN, SYN_REPORT, 1);
2264 :
2265 0 : if (dev->rep[REP_PERIOD])
2266 0 : mod_timer(&dev->timer, jiffies +
2267 0 : msecs_to_jiffies(dev->rep[REP_PERIOD]));
2268 : }
2269 :
2270 0 : spin_unlock_irqrestore(&dev->event_lock, flags);
2271 0 : }
2272 :
2273 : /**
2274 : * input_enable_softrepeat - enable software autorepeat
2275 : * @dev: input device
2276 : * @delay: repeat delay
2277 : * @period: repeat period
2278 : *
2279 : * Enable software autorepeat on the input device.
2280 : */
2281 0 : void input_enable_softrepeat(struct input_dev *dev, int delay, int period)
2282 : {
2283 0 : dev->timer.function = input_repeat_key;
2284 0 : dev->rep[REP_DELAY] = delay;
2285 0 : dev->rep[REP_PERIOD] = period;
2286 0 : }
2287 : EXPORT_SYMBOL(input_enable_softrepeat);
2288 :
2289 0 : bool input_device_enabled(struct input_dev *dev)
2290 : {
2291 : lockdep_assert_held(&dev->mutex);
2292 :
2293 0 : return !dev->inhibited && dev->users > 0;
2294 : }
2295 : EXPORT_SYMBOL_GPL(input_device_enabled);
2296 :
2297 : /**
2298 : * input_register_device - register device with input core
2299 : * @dev: device to be registered
2300 : *
2301 : * This function registers device with input core. The device must be
2302 : * allocated with input_allocate_device() and all it's capabilities
2303 : * set up before registering.
2304 : * If function fails the device must be freed with input_free_device().
2305 : * Once device has been successfully registered it can be unregistered
2306 : * with input_unregister_device(); input_free_device() should not be
2307 : * called in this case.
2308 : *
2309 : * Note that this function is also used to register managed input devices
2310 : * (ones allocated with devm_input_allocate_device()). Such managed input
2311 : * devices need not be explicitly unregistered or freed, their tear down
2312 : * is controlled by the devres infrastructure. It is also worth noting
2313 : * that tear down of managed input devices is internally a 2-step process:
2314 : * registered managed input device is first unregistered, but stays in
2315 : * memory and can still handle input_event() calls (although events will
2316 : * not be delivered anywhere). The freeing of managed input device will
2317 : * happen later, when devres stack is unwound to the point where device
2318 : * allocation was made.
2319 : */
2320 0 : int input_register_device(struct input_dev *dev)
2321 : {
2322 0 : struct input_devres *devres = NULL;
2323 : struct input_handler *handler;
2324 : unsigned int packet_size;
2325 : const char *path;
2326 : int error;
2327 :
2328 0 : if (test_bit(EV_ABS, dev->evbit) && !dev->absinfo) {
2329 0 : dev_err(&dev->dev,
2330 : "Absolute device without dev->absinfo, refusing to register\n");
2331 0 : return -EINVAL;
2332 : }
2333 :
2334 0 : if (dev->devres_managed) {
2335 0 : devres = devres_alloc(devm_input_device_unregister,
2336 : sizeof(*devres), GFP_KERNEL);
2337 0 : if (!devres)
2338 : return -ENOMEM;
2339 :
2340 0 : devres->input = dev;
2341 : }
2342 :
2343 : /* Every input device generates EV_SYN/SYN_REPORT events. */
2344 0 : __set_bit(EV_SYN, dev->evbit);
2345 :
2346 : /* KEY_RESERVED is not supposed to be transmitted to userspace. */
2347 0 : __clear_bit(KEY_RESERVED, dev->keybit);
2348 :
2349 : /* Make sure that bitmasks not mentioned in dev->evbit are clean. */
2350 0 : input_cleanse_bitmasks(dev);
2351 :
2352 0 : packet_size = input_estimate_events_per_packet(dev);
2353 0 : if (dev->hint_events_per_packet < packet_size)
2354 0 : dev->hint_events_per_packet = packet_size;
2355 :
2356 0 : dev->max_vals = dev->hint_events_per_packet + 2;
2357 0 : dev->vals = kcalloc(dev->max_vals, sizeof(*dev->vals), GFP_KERNEL);
2358 0 : if (!dev->vals) {
2359 : error = -ENOMEM;
2360 : goto err_devres_free;
2361 : }
2362 :
2363 : /*
2364 : * If delay and period are pre-set by the driver, then autorepeating
2365 : * is handled by the driver itself and we don't do it in input.c.
2366 : */
2367 0 : if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD])
2368 : input_enable_softrepeat(dev, 250, 33);
2369 :
2370 0 : if (!dev->getkeycode)
2371 0 : dev->getkeycode = input_default_getkeycode;
2372 :
2373 0 : if (!dev->setkeycode)
2374 0 : dev->setkeycode = input_default_setkeycode;
2375 :
2376 0 : if (dev->poller)
2377 0 : input_dev_poller_finalize(dev->poller);
2378 :
2379 0 : error = device_add(&dev->dev);
2380 0 : if (error)
2381 : goto err_free_vals;
2382 :
2383 0 : path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
2384 0 : pr_info("%s as %s\n",
2385 : dev->name ? dev->name : "Unspecified device",
2386 : path ? path : "N/A");
2387 0 : kfree(path);
2388 :
2389 0 : error = mutex_lock_interruptible(&input_mutex);
2390 0 : if (error)
2391 : goto err_device_del;
2392 :
2393 0 : list_add_tail(&dev->node, &input_dev_list);
2394 :
2395 0 : list_for_each_entry(handler, &input_handler_list, node)
2396 0 : input_attach_handler(dev, handler);
2397 :
2398 : input_wakeup_procfs_readers();
2399 :
2400 0 : mutex_unlock(&input_mutex);
2401 :
2402 0 : if (dev->devres_managed) {
2403 : dev_dbg(dev->dev.parent, "%s: registering %s with devres.\n",
2404 : __func__, dev_name(&dev->dev));
2405 0 : devres_add(dev->dev.parent, devres);
2406 : }
2407 : return 0;
2408 :
2409 : err_device_del:
2410 0 : device_del(&dev->dev);
2411 : err_free_vals:
2412 0 : kfree(dev->vals);
2413 0 : dev->vals = NULL;
2414 : err_devres_free:
2415 0 : devres_free(devres);
2416 0 : return error;
2417 : }
2418 : EXPORT_SYMBOL(input_register_device);
2419 :
2420 : /**
2421 : * input_unregister_device - unregister previously registered device
2422 : * @dev: device to be unregistered
2423 : *
2424 : * This function unregisters an input device. Once device is unregistered
2425 : * the caller should not try to access it as it may get freed at any moment.
2426 : */
2427 0 : void input_unregister_device(struct input_dev *dev)
2428 : {
2429 0 : if (dev->devres_managed) {
2430 0 : WARN_ON(devres_destroy(dev->dev.parent,
2431 : devm_input_device_unregister,
2432 : devm_input_device_match,
2433 : dev));
2434 0 : __input_unregister_device(dev);
2435 : /*
2436 : * We do not do input_put_device() here because it will be done
2437 : * when 2nd devres fires up.
2438 : */
2439 : } else {
2440 0 : __input_unregister_device(dev);
2441 : input_put_device(dev);
2442 : }
2443 0 : }
2444 : EXPORT_SYMBOL(input_unregister_device);
2445 :
2446 : /**
2447 : * input_register_handler - register a new input handler
2448 : * @handler: handler to be registered
2449 : *
2450 : * This function registers a new input handler (interface) for input
2451 : * devices in the system and attaches it to all input devices that
2452 : * are compatible with the handler.
2453 : */
2454 0 : int input_register_handler(struct input_handler *handler)
2455 : {
2456 : struct input_dev *dev;
2457 : int error;
2458 :
2459 0 : error = mutex_lock_interruptible(&input_mutex);
2460 0 : if (error)
2461 : return error;
2462 :
2463 0 : INIT_LIST_HEAD(&handler->h_list);
2464 :
2465 0 : list_add_tail(&handler->node, &input_handler_list);
2466 :
2467 0 : list_for_each_entry(dev, &input_dev_list, node)
2468 0 : input_attach_handler(dev, handler);
2469 :
2470 : input_wakeup_procfs_readers();
2471 :
2472 0 : mutex_unlock(&input_mutex);
2473 0 : return 0;
2474 : }
2475 : EXPORT_SYMBOL(input_register_handler);
2476 :
2477 : /**
2478 : * input_unregister_handler - unregisters an input handler
2479 : * @handler: handler to be unregistered
2480 : *
2481 : * This function disconnects a handler from its input devices and
2482 : * removes it from lists of known handlers.
2483 : */
2484 0 : void input_unregister_handler(struct input_handler *handler)
2485 : {
2486 : struct input_handle *handle, *next;
2487 :
2488 0 : mutex_lock(&input_mutex);
2489 :
2490 0 : list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
2491 0 : handler->disconnect(handle);
2492 0 : WARN_ON(!list_empty(&handler->h_list));
2493 :
2494 0 : list_del_init(&handler->node);
2495 :
2496 : input_wakeup_procfs_readers();
2497 :
2498 0 : mutex_unlock(&input_mutex);
2499 0 : }
2500 : EXPORT_SYMBOL(input_unregister_handler);
2501 :
2502 : /**
2503 : * input_handler_for_each_handle - handle iterator
2504 : * @handler: input handler to iterate
2505 : * @data: data for the callback
2506 : * @fn: function to be called for each handle
2507 : *
2508 : * Iterate over @bus's list of devices, and call @fn for each, passing
2509 : * it @data and stop when @fn returns a non-zero value. The function is
2510 : * using RCU to traverse the list and therefore may be using in atomic
2511 : * contexts. The @fn callback is invoked from RCU critical section and
2512 : * thus must not sleep.
2513 : */
2514 0 : int input_handler_for_each_handle(struct input_handler *handler, void *data,
2515 : int (*fn)(struct input_handle *, void *))
2516 : {
2517 : struct input_handle *handle;
2518 0 : int retval = 0;
2519 :
2520 : rcu_read_lock();
2521 :
2522 0 : list_for_each_entry_rcu(handle, &handler->h_list, h_node) {
2523 0 : retval = fn(handle, data);
2524 0 : if (retval)
2525 : break;
2526 : }
2527 :
2528 : rcu_read_unlock();
2529 :
2530 0 : return retval;
2531 : }
2532 : EXPORT_SYMBOL(input_handler_for_each_handle);
2533 :
2534 : /**
2535 : * input_register_handle - register a new input handle
2536 : * @handle: handle to register
2537 : *
2538 : * This function puts a new input handle onto device's
2539 : * and handler's lists so that events can flow through
2540 : * it once it is opened using input_open_device().
2541 : *
2542 : * This function is supposed to be called from handler's
2543 : * connect() method.
2544 : */
2545 0 : int input_register_handle(struct input_handle *handle)
2546 : {
2547 0 : struct input_handler *handler = handle->handler;
2548 0 : struct input_dev *dev = handle->dev;
2549 : int error;
2550 :
2551 : /*
2552 : * We take dev->mutex here to prevent race with
2553 : * input_release_device().
2554 : */
2555 0 : error = mutex_lock_interruptible(&dev->mutex);
2556 0 : if (error)
2557 : return error;
2558 :
2559 : /*
2560 : * Filters go to the head of the list, normal handlers
2561 : * to the tail.
2562 : */
2563 0 : if (handler->filter)
2564 0 : list_add_rcu(&handle->d_node, &dev->h_list);
2565 : else
2566 0 : list_add_tail_rcu(&handle->d_node, &dev->h_list);
2567 :
2568 0 : mutex_unlock(&dev->mutex);
2569 :
2570 : /*
2571 : * Since we are supposed to be called from ->connect()
2572 : * which is mutually exclusive with ->disconnect()
2573 : * we can't be racing with input_unregister_handle()
2574 : * and so separate lock is not needed here.
2575 : */
2576 0 : list_add_tail_rcu(&handle->h_node, &handler->h_list);
2577 :
2578 0 : if (handler->start)
2579 0 : handler->start(handle);
2580 :
2581 : return 0;
2582 : }
2583 : EXPORT_SYMBOL(input_register_handle);
2584 :
2585 : /**
2586 : * input_unregister_handle - unregister an input handle
2587 : * @handle: handle to unregister
2588 : *
2589 : * This function removes input handle from device's
2590 : * and handler's lists.
2591 : *
2592 : * This function is supposed to be called from handler's
2593 : * disconnect() method.
2594 : */
2595 0 : void input_unregister_handle(struct input_handle *handle)
2596 : {
2597 0 : struct input_dev *dev = handle->dev;
2598 :
2599 0 : list_del_rcu(&handle->h_node);
2600 :
2601 : /*
2602 : * Take dev->mutex to prevent race with input_release_device().
2603 : */
2604 0 : mutex_lock(&dev->mutex);
2605 0 : list_del_rcu(&handle->d_node);
2606 0 : mutex_unlock(&dev->mutex);
2607 :
2608 0 : synchronize_rcu();
2609 0 : }
2610 : EXPORT_SYMBOL(input_unregister_handle);
2611 :
2612 : /**
2613 : * input_get_new_minor - allocates a new input minor number
2614 : * @legacy_base: beginning or the legacy range to be searched
2615 : * @legacy_num: size of legacy range
2616 : * @allow_dynamic: whether we can also take ID from the dynamic range
2617 : *
2618 : * This function allocates a new device minor for from input major namespace.
2619 : * Caller can request legacy minor by specifying @legacy_base and @legacy_num
2620 : * parameters and whether ID can be allocated from dynamic range if there are
2621 : * no free IDs in legacy range.
2622 : */
2623 0 : int input_get_new_minor(int legacy_base, unsigned int legacy_num,
2624 : bool allow_dynamic)
2625 : {
2626 : /*
2627 : * This function should be called from input handler's ->connect()
2628 : * methods, which are serialized with input_mutex, so no additional
2629 : * locking is needed here.
2630 : */
2631 0 : if (legacy_base >= 0) {
2632 0 : int minor = ida_simple_get(&input_ida,
2633 : legacy_base,
2634 : legacy_base + legacy_num,
2635 : GFP_KERNEL);
2636 0 : if (minor >= 0 || !allow_dynamic)
2637 : return minor;
2638 : }
2639 :
2640 0 : return ida_simple_get(&input_ida,
2641 : INPUT_FIRST_DYNAMIC_DEV, INPUT_MAX_CHAR_DEVICES,
2642 : GFP_KERNEL);
2643 : }
2644 : EXPORT_SYMBOL(input_get_new_minor);
2645 :
2646 : /**
2647 : * input_free_minor - release previously allocated minor
2648 : * @minor: minor to be released
2649 : *
2650 : * This function releases previously allocated input minor so that it can be
2651 : * reused later.
2652 : */
2653 0 : void input_free_minor(unsigned int minor)
2654 : {
2655 0 : ida_simple_remove(&input_ida, minor);
2656 0 : }
2657 : EXPORT_SYMBOL(input_free_minor);
2658 :
2659 1 : static int __init input_init(void)
2660 : {
2661 : int err;
2662 :
2663 1 : err = class_register(&input_class);
2664 1 : if (err) {
2665 0 : pr_err("unable to register input_dev class\n");
2666 0 : return err;
2667 : }
2668 :
2669 1 : err = input_proc_init();
2670 1 : if (err)
2671 : goto fail1;
2672 :
2673 1 : err = register_chrdev_region(MKDEV(INPUT_MAJOR, 0),
2674 : INPUT_MAX_CHAR_DEVICES, "input");
2675 1 : if (err) {
2676 0 : pr_err("unable to register char major %d", INPUT_MAJOR);
2677 : goto fail2;
2678 : }
2679 :
2680 : return 0;
2681 :
2682 0 : fail2: input_proc_exit();
2683 0 : fail1: class_unregister(&input_class);
2684 0 : return err;
2685 : }
2686 :
2687 0 : static void __exit input_exit(void)
2688 : {
2689 0 : input_proc_exit();
2690 0 : unregister_chrdev_region(MKDEV(INPUT_MAJOR, 0),
2691 : INPUT_MAX_CHAR_DEVICES);
2692 0 : class_unregister(&input_class);
2693 0 : }
2694 :
2695 : subsys_initcall(input_init);
2696 : module_exit(input_exit);
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