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