Linux Audio

Check our new training course

Open-source upstreaming

Need help get the support for your hardware in upstream Linux?
Loading...
v4.6
 
   1/*
   2 * The input core
   3 *
   4 * Copyright (c) 1999-2002 Vojtech Pavlik
   5 */
   6
   7/*
   8 * This program is free software; you can redistribute it and/or modify it
   9 * under the terms of the GNU General Public License version 2 as published by
  10 * the Free Software Foundation.
  11 */
  12
  13#define pr_fmt(fmt) KBUILD_BASENAME ": " fmt
  14
  15#include <linux/init.h>
  16#include <linux/types.h>
  17#include <linux/idr.h>
  18#include <linux/input/mt.h>
  19#include <linux/module.h>
  20#include <linux/slab.h>
  21#include <linux/random.h>
  22#include <linux/major.h>
  23#include <linux/proc_fs.h>
  24#include <linux/sched.h>
  25#include <linux/seq_file.h>
  26#include <linux/poll.h>
  27#include <linux/device.h>
  28#include <linux/mutex.h>
  29#include <linux/rcupdate.h>
  30#include "input-compat.h"
 
  31
  32MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
  33MODULE_DESCRIPTION("Input core");
  34MODULE_LICENSE("GPL");
  35
  36#define INPUT_MAX_CHAR_DEVICES		1024
  37#define INPUT_FIRST_DYNAMIC_DEV		256
  38static DEFINE_IDA(input_ida);
  39
  40static LIST_HEAD(input_dev_list);
  41static 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 */
  49static DEFINE_MUTEX(input_mutex);
  50
  51static const struct input_value input_value_sync = { EV_SYN, SYN_REPORT, 1 };
  52
  53static inline int is_event_supported(unsigned int code,
  54				     unsigned long *bm, unsigned int max)
  55{
  56	return code <= max && test_bit(code, bm);
  57}
  58
  59static int input_defuzz_abs_event(int value, int old_val, int fuzz)
  60{
  61	if (fuzz) {
  62		if (value > old_val - fuzz / 2 && value < old_val + fuzz / 2)
  63			return old_val;
  64
  65		if (value > old_val - fuzz && value < old_val + fuzz)
  66			return (old_val * 3 + value) / 4;
  67
  68		if (value > old_val - fuzz * 2 && value < old_val + fuzz * 2)
  69			return (old_val + value) / 2;
  70	}
  71
  72	return value;
  73}
  74
  75static void input_start_autorepeat(struct input_dev *dev, int code)
  76{
  77	if (test_bit(EV_REP, dev->evbit) &&
  78	    dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] &&
  79	    dev->timer.data) {
  80		dev->repeat_key = code;
  81		mod_timer(&dev->timer,
  82			  jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
  83	}
  84}
  85
  86static void input_stop_autorepeat(struct input_dev *dev)
  87{
  88	del_timer(&dev->timer);
  89}
  90
  91/*
  92 * Pass event first through all filters and then, if event has not been
  93 * filtered out, through all open handles. This function is called with
  94 * dev->event_lock held and interrupts disabled.
  95 */
  96static unsigned int input_to_handler(struct input_handle *handle,
  97			struct input_value *vals, unsigned int count)
  98{
  99	struct input_handler *handler = handle->handler;
 100	struct input_value *end = vals;
 101	struct input_value *v;
 102
 103	if (handler->filter) {
 104		for (v = vals; v != vals + count; v++) {
 105			if (handler->filter(handle, v->type, v->code, v->value))
 106				continue;
 107			if (end != v)
 108				*end = *v;
 109			end++;
 110		}
 111		count = end - vals;
 112	}
 113
 114	if (!count)
 115		return 0;
 116
 117	if (handler->events)
 118		handler->events(handle, vals, count);
 119	else if (handler->event)
 120		for (v = vals; v != vals + count; v++)
 121			handler->event(handle, v->type, v->code, v->value);
 122
 123	return count;
 124}
 125
 126/*
 127 * Pass values first through all filters and then, if event has not been
 128 * filtered out, through all open handles. This function is called with
 129 * dev->event_lock held and interrupts disabled.
 130 */
 131static void input_pass_values(struct input_dev *dev,
 132			      struct input_value *vals, unsigned int count)
 133{
 134	struct input_handle *handle;
 135	struct input_value *v;
 136
 137	if (!count)
 138		return;
 139
 140	rcu_read_lock();
 141
 142	handle = rcu_dereference(dev->grab);
 143	if (handle) {
 144		count = input_to_handler(handle, vals, count);
 145	} else {
 146		list_for_each_entry_rcu(handle, &dev->h_list, d_node)
 147			if (handle->open) {
 148				count = input_to_handler(handle, vals, count);
 149				if (!count)
 150					break;
 151			}
 152	}
 153
 154	rcu_read_unlock();
 155
 156	add_input_randomness(vals->type, vals->code, vals->value);
 157
 158	/* trigger auto repeat for key events */
 159	if (test_bit(EV_REP, dev->evbit) && test_bit(EV_KEY, dev->evbit)) {
 160		for (v = vals; v != vals + count; v++) {
 161			if (v->type == EV_KEY && v->value != 2) {
 162				if (v->value)
 163					input_start_autorepeat(dev, v->code);
 164				else
 165					input_stop_autorepeat(dev);
 166			}
 167		}
 168	}
 169}
 170
 171static void input_pass_event(struct input_dev *dev,
 172			     unsigned int type, unsigned int code, int value)
 173{
 174	struct input_value vals[] = { { type, code, value } };
 175
 176	input_pass_values(dev, vals, ARRAY_SIZE(vals));
 177}
 178
 179/*
 180 * Generate software autorepeat event. Note that we take
 181 * dev->event_lock here to avoid racing with input_event
 182 * which may cause keys get "stuck".
 183 */
 184static void input_repeat_key(unsigned long data)
 185{
 186	struct input_dev *dev = (void *) data;
 187	unsigned long flags;
 188
 189	spin_lock_irqsave(&dev->event_lock, flags);
 190
 191	if (test_bit(dev->repeat_key, dev->key) &&
 192	    is_event_supported(dev->repeat_key, dev->keybit, KEY_MAX)) {
 193		struct input_value vals[] =  {
 194			{ EV_KEY, dev->repeat_key, 2 },
 195			input_value_sync
 196		};
 197
 
 198		input_pass_values(dev, vals, ARRAY_SIZE(vals));
 199
 200		if (dev->rep[REP_PERIOD])
 201			mod_timer(&dev->timer, jiffies +
 202					msecs_to_jiffies(dev->rep[REP_PERIOD]));
 203	}
 204
 205	spin_unlock_irqrestore(&dev->event_lock, flags);
 206}
 207
 208#define INPUT_IGNORE_EVENT	0
 209#define INPUT_PASS_TO_HANDLERS	1
 210#define INPUT_PASS_TO_DEVICE	2
 211#define INPUT_SLOT		4
 212#define INPUT_FLUSH		8
 213#define INPUT_PASS_TO_ALL	(INPUT_PASS_TO_HANDLERS | INPUT_PASS_TO_DEVICE)
 214
 215static int input_handle_abs_event(struct input_dev *dev,
 216				  unsigned int code, int *pval)
 217{
 218	struct input_mt *mt = dev->mt;
 219	bool is_mt_event;
 220	int *pold;
 221
 222	if (code == ABS_MT_SLOT) {
 223		/*
 224		 * "Stage" the event; we'll flush it later, when we
 225		 * get actual touch data.
 226		 */
 227		if (mt && *pval >= 0 && *pval < mt->num_slots)
 228			mt->slot = *pval;
 229
 230		return INPUT_IGNORE_EVENT;
 231	}
 232
 233	is_mt_event = input_is_mt_value(code);
 234
 235	if (!is_mt_event) {
 236		pold = &dev->absinfo[code].value;
 237	} else if (mt) {
 238		pold = &mt->slots[mt->slot].abs[code - ABS_MT_FIRST];
 239	} else {
 240		/*
 241		 * Bypass filtering for multi-touch events when
 242		 * not employing slots.
 243		 */
 244		pold = NULL;
 245	}
 246
 247	if (pold) {
 248		*pval = input_defuzz_abs_event(*pval, *pold,
 249						dev->absinfo[code].fuzz);
 250		if (*pold == *pval)
 251			return INPUT_IGNORE_EVENT;
 252
 253		*pold = *pval;
 254	}
 255
 256	/* Flush pending "slot" event */
 257	if (is_mt_event && mt && mt->slot != input_abs_get_val(dev, ABS_MT_SLOT)) {
 258		input_abs_set_val(dev, ABS_MT_SLOT, mt->slot);
 259		return INPUT_PASS_TO_HANDLERS | INPUT_SLOT;
 260	}
 261
 262	return INPUT_PASS_TO_HANDLERS;
 263}
 264
 265static int input_get_disposition(struct input_dev *dev,
 266			  unsigned int type, unsigned int code, int *pval)
 267{
 268	int disposition = INPUT_IGNORE_EVENT;
 269	int value = *pval;
 270
 271	switch (type) {
 272
 273	case EV_SYN:
 274		switch (code) {
 275		case SYN_CONFIG:
 276			disposition = INPUT_PASS_TO_ALL;
 277			break;
 278
 279		case SYN_REPORT:
 280			disposition = INPUT_PASS_TO_HANDLERS | INPUT_FLUSH;
 281			break;
 282		case SYN_MT_REPORT:
 283			disposition = INPUT_PASS_TO_HANDLERS;
 284			break;
 285		}
 286		break;
 287
 288	case EV_KEY:
 289		if (is_event_supported(code, dev->keybit, KEY_MAX)) {
 290
 291			/* auto-repeat bypasses state updates */
 292			if (value == 2) {
 293				disposition = INPUT_PASS_TO_HANDLERS;
 294				break;
 295			}
 296
 297			if (!!test_bit(code, dev->key) != !!value) {
 298
 299				__change_bit(code, dev->key);
 300				disposition = INPUT_PASS_TO_HANDLERS;
 301			}
 302		}
 303		break;
 304
 305	case EV_SW:
 306		if (is_event_supported(code, dev->swbit, SW_MAX) &&
 307		    !!test_bit(code, dev->sw) != !!value) {
 308
 309			__change_bit(code, dev->sw);
 310			disposition = INPUT_PASS_TO_HANDLERS;
 311		}
 312		break;
 313
 314	case EV_ABS:
 315		if (is_event_supported(code, dev->absbit, ABS_MAX))
 316			disposition = input_handle_abs_event(dev, code, &value);
 317
 318		break;
 319
 320	case EV_REL:
 321		if (is_event_supported(code, dev->relbit, REL_MAX) && value)
 322			disposition = INPUT_PASS_TO_HANDLERS;
 323
 324		break;
 325
 326	case EV_MSC:
 327		if (is_event_supported(code, dev->mscbit, MSC_MAX))
 328			disposition = INPUT_PASS_TO_ALL;
 329
 330		break;
 331
 332	case EV_LED:
 333		if (is_event_supported(code, dev->ledbit, LED_MAX) &&
 334		    !!test_bit(code, dev->led) != !!value) {
 335
 336			__change_bit(code, dev->led);
 337			disposition = INPUT_PASS_TO_ALL;
 338		}
 339		break;
 340
 341	case EV_SND:
 342		if (is_event_supported(code, dev->sndbit, SND_MAX)) {
 343
 344			if (!!test_bit(code, dev->snd) != !!value)
 345				__change_bit(code, dev->snd);
 346			disposition = INPUT_PASS_TO_ALL;
 347		}
 348		break;
 349
 350	case EV_REP:
 351		if (code <= REP_MAX && value >= 0 && dev->rep[code] != value) {
 352			dev->rep[code] = value;
 353			disposition = INPUT_PASS_TO_ALL;
 354		}
 355		break;
 356
 357	case EV_FF:
 358		if (value >= 0)
 359			disposition = INPUT_PASS_TO_ALL;
 360		break;
 361
 362	case EV_PWR:
 363		disposition = INPUT_PASS_TO_ALL;
 364		break;
 365	}
 366
 367	*pval = value;
 368	return disposition;
 369}
 370
 371static void input_handle_event(struct input_dev *dev,
 372			       unsigned int type, unsigned int code, int value)
 373{
 374	int disposition;
 375
 
 
 
 
 376	disposition = input_get_disposition(dev, type, code, &value);
 
 
 377
 378	if ((disposition & INPUT_PASS_TO_DEVICE) && dev->event)
 379		dev->event(dev, type, code, value);
 380
 381	if (!dev->vals)
 382		return;
 383
 384	if (disposition & INPUT_PASS_TO_HANDLERS) {
 385		struct input_value *v;
 386
 387		if (disposition & INPUT_SLOT) {
 388			v = &dev->vals[dev->num_vals++];
 389			v->type = EV_ABS;
 390			v->code = ABS_MT_SLOT;
 391			v->value = dev->mt->slot;
 392		}
 393
 394		v = &dev->vals[dev->num_vals++];
 395		v->type = type;
 396		v->code = code;
 397		v->value = value;
 398	}
 399
 400	if (disposition & INPUT_FLUSH) {
 401		if (dev->num_vals >= 2)
 402			input_pass_values(dev, dev->vals, dev->num_vals);
 403		dev->num_vals = 0;
 
 
 
 
 
 
 
 404	} else if (dev->num_vals >= dev->max_vals - 2) {
 405		dev->vals[dev->num_vals++] = input_value_sync;
 406		input_pass_values(dev, dev->vals, dev->num_vals);
 407		dev->num_vals = 0;
 408	}
 409
 410}
 411
 412/**
 413 * input_event() - report new input event
 414 * @dev: device that generated the event
 415 * @type: type of the event
 416 * @code: event code
 417 * @value: value of the event
 418 *
 419 * This function should be used by drivers implementing various input
 420 * devices to report input events. See also input_inject_event().
 421 *
 422 * NOTE: input_event() may be safely used right after input device was
 423 * allocated with input_allocate_device(), even before it is registered
 424 * with input_register_device(), but the event will not reach any of the
 425 * input handlers. Such early invocation of input_event() may be used
 426 * to 'seed' initial state of a switch or initial position of absolute
 427 * axis, etc.
 428 */
 429void input_event(struct input_dev *dev,
 430		 unsigned int type, unsigned int code, int value)
 431{
 432	unsigned long flags;
 433
 434	if (is_event_supported(type, dev->evbit, EV_MAX)) {
 435
 436		spin_lock_irqsave(&dev->event_lock, flags);
 437		input_handle_event(dev, type, code, value);
 438		spin_unlock_irqrestore(&dev->event_lock, flags);
 439	}
 440}
 441EXPORT_SYMBOL(input_event);
 442
 443/**
 444 * input_inject_event() - send input event from input handler
 445 * @handle: input handle to send event through
 446 * @type: type of the event
 447 * @code: event code
 448 * @value: value of the event
 449 *
 450 * Similar to input_event() but will ignore event if device is
 451 * "grabbed" and handle injecting event is not the one that owns
 452 * the device.
 453 */
 454void input_inject_event(struct input_handle *handle,
 455			unsigned int type, unsigned int code, int value)
 456{
 457	struct input_dev *dev = handle->dev;
 458	struct input_handle *grab;
 459	unsigned long flags;
 460
 461	if (is_event_supported(type, dev->evbit, EV_MAX)) {
 462		spin_lock_irqsave(&dev->event_lock, flags);
 463
 464		rcu_read_lock();
 465		grab = rcu_dereference(dev->grab);
 466		if (!grab || grab == handle)
 467			input_handle_event(dev, type, code, value);
 468		rcu_read_unlock();
 469
 470		spin_unlock_irqrestore(&dev->event_lock, flags);
 471	}
 472}
 473EXPORT_SYMBOL(input_inject_event);
 474
 475/**
 476 * input_alloc_absinfo - allocates array of input_absinfo structs
 477 * @dev: the input device emitting absolute events
 478 *
 479 * If the absinfo struct the caller asked for is already allocated, this
 480 * functions will not do anything.
 481 */
 482void input_alloc_absinfo(struct input_dev *dev)
 483{
 484	if (!dev->absinfo)
 485		dev->absinfo = kcalloc(ABS_CNT, sizeof(struct input_absinfo),
 486					GFP_KERNEL);
 487
 488	WARN(!dev->absinfo, "%s(): kcalloc() failed?\n", __func__);
 
 
 
 
 
 
 
 
 
 489}
 490EXPORT_SYMBOL(input_alloc_absinfo);
 491
 492void input_set_abs_params(struct input_dev *dev, unsigned int axis,
 493			  int min, int max, int fuzz, int flat)
 494{
 495	struct input_absinfo *absinfo;
 496
 497	input_alloc_absinfo(dev);
 498	if (!dev->absinfo)
 499		return;
 500
 501	absinfo = &dev->absinfo[axis];
 502	absinfo->minimum = min;
 503	absinfo->maximum = max;
 504	absinfo->fuzz = fuzz;
 505	absinfo->flat = flat;
 506
 507	__set_bit(EV_ABS, dev->evbit);
 508	__set_bit(axis, dev->absbit);
 509}
 510EXPORT_SYMBOL(input_set_abs_params);
 511
 512
 513/**
 514 * input_grab_device - grabs device for exclusive use
 515 * @handle: input handle that wants to own the device
 516 *
 517 * When a device is grabbed by an input handle all events generated by
 518 * the device are delivered only to this handle. Also events injected
 519 * by other input handles are ignored while device is grabbed.
 520 */
 521int input_grab_device(struct input_handle *handle)
 522{
 523	struct input_dev *dev = handle->dev;
 524	int retval;
 525
 526	retval = mutex_lock_interruptible(&dev->mutex);
 527	if (retval)
 528		return retval;
 529
 530	if (dev->grab) {
 531		retval = -EBUSY;
 532		goto out;
 533	}
 534
 535	rcu_assign_pointer(dev->grab, handle);
 536
 537 out:
 538	mutex_unlock(&dev->mutex);
 539	return retval;
 540}
 541EXPORT_SYMBOL(input_grab_device);
 542
 543static void __input_release_device(struct input_handle *handle)
 544{
 545	struct input_dev *dev = handle->dev;
 546	struct input_handle *grabber;
 547
 548	grabber = rcu_dereference_protected(dev->grab,
 549					    lockdep_is_held(&dev->mutex));
 550	if (grabber == handle) {
 551		rcu_assign_pointer(dev->grab, NULL);
 552		/* Make sure input_pass_event() notices that grab is gone */
 553		synchronize_rcu();
 554
 555		list_for_each_entry(handle, &dev->h_list, d_node)
 556			if (handle->open && handle->handler->start)
 557				handle->handler->start(handle);
 558	}
 559}
 560
 561/**
 562 * input_release_device - release previously grabbed device
 563 * @handle: input handle that owns the device
 564 *
 565 * Releases previously grabbed device so that other input handles can
 566 * start receiving input events. Upon release all handlers attached
 567 * to the device have their start() method called so they have a change
 568 * to synchronize device state with the rest of the system.
 569 */
 570void input_release_device(struct input_handle *handle)
 571{
 572	struct input_dev *dev = handle->dev;
 573
 574	mutex_lock(&dev->mutex);
 575	__input_release_device(handle);
 576	mutex_unlock(&dev->mutex);
 577}
 578EXPORT_SYMBOL(input_release_device);
 579
 580/**
 581 * input_open_device - open input device
 582 * @handle: handle through which device is being accessed
 583 *
 584 * This function should be called by input handlers when they
 585 * want to start receive events from given input device.
 586 */
 587int input_open_device(struct input_handle *handle)
 588{
 589	struct input_dev *dev = handle->dev;
 590	int retval;
 591
 592	retval = mutex_lock_interruptible(&dev->mutex);
 593	if (retval)
 594		return retval;
 595
 596	if (dev->going_away) {
 597		retval = -ENODEV;
 598		goto out;
 599	}
 600
 601	handle->open++;
 602
 603	if (!dev->users++ && dev->open)
 604		retval = dev->open(dev);
 
 
 
 
 
 605
 606	if (retval) {
 607		dev->users--;
 608		if (!--handle->open) {
 
 
 609			/*
 610			 * Make sure we are not delivering any more events
 611			 * through this handle
 612			 */
 613			synchronize_rcu();
 
 614		}
 615	}
 616
 
 
 
 617 out:
 618	mutex_unlock(&dev->mutex);
 619	return retval;
 620}
 621EXPORT_SYMBOL(input_open_device);
 622
 623int input_flush_device(struct input_handle *handle, struct file *file)
 624{
 625	struct input_dev *dev = handle->dev;
 626	int retval;
 627
 628	retval = mutex_lock_interruptible(&dev->mutex);
 629	if (retval)
 630		return retval;
 631
 632	if (dev->flush)
 633		retval = dev->flush(dev, file);
 634
 635	mutex_unlock(&dev->mutex);
 636	return retval;
 637}
 638EXPORT_SYMBOL(input_flush_device);
 639
 640/**
 641 * input_close_device - close input device
 642 * @handle: handle through which device is being accessed
 643 *
 644 * This function should be called by input handlers when they
 645 * want to stop receive events from given input device.
 646 */
 647void input_close_device(struct input_handle *handle)
 648{
 649	struct input_dev *dev = handle->dev;
 650
 651	mutex_lock(&dev->mutex);
 652
 653	__input_release_device(handle);
 654
 655	if (!--dev->users && dev->close)
 656		dev->close(dev);
 
 
 
 
 657
 658	if (!--handle->open) {
 659		/*
 660		 * synchronize_rcu() makes sure that input_pass_event()
 661		 * completed and that no more input events are delivered
 662		 * through this handle
 663		 */
 664		synchronize_rcu();
 665	}
 666
 667	mutex_unlock(&dev->mutex);
 668}
 669EXPORT_SYMBOL(input_close_device);
 670
 671/*
 672 * Simulate keyup events for all keys that are marked as pressed.
 673 * The function must be called with dev->event_lock held.
 674 */
 675static void input_dev_release_keys(struct input_dev *dev)
 676{
 677	bool need_sync = false;
 678	int code;
 679
 680	if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
 681		for_each_set_bit(code, dev->key, KEY_CNT) {
 682			input_pass_event(dev, EV_KEY, code, 0);
 683			need_sync = true;
 684		}
 685
 686		if (need_sync)
 687			input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
 688
 689		memset(dev->key, 0, sizeof(dev->key));
 690	}
 691}
 692
 693/*
 694 * Prepare device for unregistering
 695 */
 696static void input_disconnect_device(struct input_dev *dev)
 697{
 698	struct input_handle *handle;
 699
 700	/*
 701	 * Mark device as going away. Note that we take dev->mutex here
 702	 * not to protect access to dev->going_away but rather to ensure
 703	 * that there are no threads in the middle of input_open_device()
 704	 */
 705	mutex_lock(&dev->mutex);
 706	dev->going_away = true;
 707	mutex_unlock(&dev->mutex);
 708
 709	spin_lock_irq(&dev->event_lock);
 710
 711	/*
 712	 * Simulate keyup events for all pressed keys so that handlers
 713	 * are not left with "stuck" keys. The driver may continue
 714	 * generate events even after we done here but they will not
 715	 * reach any handlers.
 716	 */
 717	input_dev_release_keys(dev);
 718
 719	list_for_each_entry(handle, &dev->h_list, d_node)
 720		handle->open = 0;
 721
 722	spin_unlock_irq(&dev->event_lock);
 723}
 724
 725/**
 726 * input_scancode_to_scalar() - converts scancode in &struct input_keymap_entry
 727 * @ke: keymap entry containing scancode to be converted.
 728 * @scancode: pointer to the location where converted scancode should
 729 *	be stored.
 730 *
 731 * This function is used to convert scancode stored in &struct keymap_entry
 732 * into scalar form understood by legacy keymap handling methods. These
 733 * methods expect scancodes to be represented as 'unsigned int'.
 734 */
 735int input_scancode_to_scalar(const struct input_keymap_entry *ke,
 736			     unsigned int *scancode)
 737{
 738	switch (ke->len) {
 739	case 1:
 740		*scancode = *((u8 *)ke->scancode);
 741		break;
 742
 743	case 2:
 744		*scancode = *((u16 *)ke->scancode);
 745		break;
 746
 747	case 4:
 748		*scancode = *((u32 *)ke->scancode);
 749		break;
 750
 751	default:
 752		return -EINVAL;
 753	}
 754
 755	return 0;
 756}
 757EXPORT_SYMBOL(input_scancode_to_scalar);
 758
 759/*
 760 * Those routines handle the default case where no [gs]etkeycode() is
 761 * defined. In this case, an array indexed by the scancode is used.
 762 */
 763
 764static unsigned int input_fetch_keycode(struct input_dev *dev,
 765					unsigned int index)
 766{
 767	switch (dev->keycodesize) {
 768	case 1:
 769		return ((u8 *)dev->keycode)[index];
 770
 771	case 2:
 772		return ((u16 *)dev->keycode)[index];
 773
 774	default:
 775		return ((u32 *)dev->keycode)[index];
 776	}
 777}
 778
 779static int input_default_getkeycode(struct input_dev *dev,
 780				    struct input_keymap_entry *ke)
 781{
 782	unsigned int index;
 783	int error;
 784
 785	if (!dev->keycodesize)
 786		return -EINVAL;
 787
 788	if (ke->flags & INPUT_KEYMAP_BY_INDEX)
 789		index = ke->index;
 790	else {
 791		error = input_scancode_to_scalar(ke, &index);
 792		if (error)
 793			return error;
 794	}
 795
 796	if (index >= dev->keycodemax)
 797		return -EINVAL;
 798
 799	ke->keycode = input_fetch_keycode(dev, index);
 800	ke->index = index;
 801	ke->len = sizeof(index);
 802	memcpy(ke->scancode, &index, sizeof(index));
 803
 804	return 0;
 805}
 806
 807static int input_default_setkeycode(struct input_dev *dev,
 808				    const struct input_keymap_entry *ke,
 809				    unsigned int *old_keycode)
 810{
 811	unsigned int index;
 812	int error;
 813	int i;
 814
 815	if (!dev->keycodesize)
 816		return -EINVAL;
 817
 818	if (ke->flags & INPUT_KEYMAP_BY_INDEX) {
 819		index = ke->index;
 820	} else {
 821		error = input_scancode_to_scalar(ke, &index);
 822		if (error)
 823			return error;
 824	}
 825
 826	if (index >= dev->keycodemax)
 827		return -EINVAL;
 828
 829	if (dev->keycodesize < sizeof(ke->keycode) &&
 830			(ke->keycode >> (dev->keycodesize * 8)))
 831		return -EINVAL;
 832
 833	switch (dev->keycodesize) {
 834		case 1: {
 835			u8 *k = (u8 *)dev->keycode;
 836			*old_keycode = k[index];
 837			k[index] = ke->keycode;
 838			break;
 839		}
 840		case 2: {
 841			u16 *k = (u16 *)dev->keycode;
 842			*old_keycode = k[index];
 843			k[index] = ke->keycode;
 844			break;
 845		}
 846		default: {
 847			u32 *k = (u32 *)dev->keycode;
 848			*old_keycode = k[index];
 849			k[index] = ke->keycode;
 850			break;
 851		}
 852	}
 853
 854	__clear_bit(*old_keycode, dev->keybit);
 855	__set_bit(ke->keycode, dev->keybit);
 856
 857	for (i = 0; i < dev->keycodemax; i++) {
 858		if (input_fetch_keycode(dev, i) == *old_keycode) {
 859			__set_bit(*old_keycode, dev->keybit);
 860			break; /* Setting the bit twice is useless, so break */
 
 861		}
 862	}
 863
 
 864	return 0;
 865}
 866
 867/**
 868 * input_get_keycode - retrieve keycode currently mapped to a given scancode
 869 * @dev: input device which keymap is being queried
 870 * @ke: keymap entry
 871 *
 872 * This function should be called by anyone interested in retrieving current
 873 * keymap. Presently evdev handlers use it.
 874 */
 875int input_get_keycode(struct input_dev *dev, struct input_keymap_entry *ke)
 876{
 877	unsigned long flags;
 878	int retval;
 879
 880	spin_lock_irqsave(&dev->event_lock, flags);
 881	retval = dev->getkeycode(dev, ke);
 882	spin_unlock_irqrestore(&dev->event_lock, flags);
 883
 884	return retval;
 885}
 886EXPORT_SYMBOL(input_get_keycode);
 887
 888/**
 889 * input_set_keycode - attribute a keycode to a given scancode
 890 * @dev: input device which keymap is being updated
 891 * @ke: new keymap entry
 892 *
 893 * This function should be called by anyone needing to update current
 894 * keymap. Presently keyboard and evdev handlers use it.
 895 */
 896int input_set_keycode(struct input_dev *dev,
 897		      const struct input_keymap_entry *ke)
 898{
 899	unsigned long flags;
 900	unsigned int old_keycode;
 901	int retval;
 902
 903	if (ke->keycode > KEY_MAX)
 904		return -EINVAL;
 905
 906	spin_lock_irqsave(&dev->event_lock, flags);
 907
 908	retval = dev->setkeycode(dev, ke, &old_keycode);
 909	if (retval)
 910		goto out;
 911
 912	/* Make sure KEY_RESERVED did not get enabled. */
 913	__clear_bit(KEY_RESERVED, dev->keybit);
 914
 915	/*
 916	 * Simulate keyup event if keycode is not present
 917	 * in the keymap anymore
 918	 */
 919	if (test_bit(EV_KEY, dev->evbit) &&
 920	    !is_event_supported(old_keycode, dev->keybit, KEY_MAX) &&
 921	    __test_and_clear_bit(old_keycode, dev->key)) {
 
 
 
 
 922		struct input_value vals[] =  {
 923			{ EV_KEY, old_keycode, 0 },
 924			input_value_sync
 925		};
 926
 927		input_pass_values(dev, vals, ARRAY_SIZE(vals));
 928	}
 929
 930 out:
 931	spin_unlock_irqrestore(&dev->event_lock, flags);
 932
 933	return retval;
 934}
 935EXPORT_SYMBOL(input_set_keycode);
 936
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 937static const struct input_device_id *input_match_device(struct input_handler *handler,
 938							struct input_dev *dev)
 939{
 940	const struct input_device_id *id;
 941
 942	for (id = handler->id_table; id->flags || id->driver_info; id++) {
 943
 944		if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
 945			if (id->bustype != dev->id.bustype)
 946				continue;
 947
 948		if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
 949			if (id->vendor != dev->id.vendor)
 950				continue;
 951
 952		if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
 953			if (id->product != dev->id.product)
 954				continue;
 955
 956		if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
 957			if (id->version != dev->id.version)
 958				continue;
 959
 960		if (!bitmap_subset(id->evbit, dev->evbit, EV_MAX))
 961			continue;
 962
 963		if (!bitmap_subset(id->keybit, dev->keybit, KEY_MAX))
 964			continue;
 965
 966		if (!bitmap_subset(id->relbit, dev->relbit, REL_MAX))
 967			continue;
 968
 969		if (!bitmap_subset(id->absbit, dev->absbit, ABS_MAX))
 970			continue;
 971
 972		if (!bitmap_subset(id->mscbit, dev->mscbit, MSC_MAX))
 973			continue;
 974
 975		if (!bitmap_subset(id->ledbit, dev->ledbit, LED_MAX))
 976			continue;
 977
 978		if (!bitmap_subset(id->sndbit, dev->sndbit, SND_MAX))
 979			continue;
 980
 981		if (!bitmap_subset(id->ffbit, dev->ffbit, FF_MAX))
 982			continue;
 983
 984		if (!bitmap_subset(id->swbit, dev->swbit, SW_MAX))
 985			continue;
 986
 987		if (!handler->match || handler->match(handler, dev))
 988			return id;
 
 989	}
 990
 991	return NULL;
 992}
 993
 994static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
 995{
 996	const struct input_device_id *id;
 997	int error;
 998
 999	id = input_match_device(handler, dev);
1000	if (!id)
1001		return -ENODEV;
1002
1003	error = handler->connect(handler, dev, id);
1004	if (error && error != -ENODEV)
1005		pr_err("failed to attach handler %s to device %s, error: %d\n",
1006		       handler->name, kobject_name(&dev->dev.kobj), error);
1007
1008	return error;
1009}
1010
1011#ifdef CONFIG_COMPAT
1012
1013static int input_bits_to_string(char *buf, int buf_size,
1014				unsigned long bits, bool skip_empty)
1015{
1016	int len = 0;
1017
1018	if (in_compat_syscall()) {
1019		u32 dword = bits >> 32;
1020		if (dword || !skip_empty)
1021			len += snprintf(buf, buf_size, "%x ", dword);
1022
1023		dword = bits & 0xffffffffUL;
1024		if (dword || !skip_empty || len)
1025			len += snprintf(buf + len, max(buf_size - len, 0),
1026					"%x", dword);
1027	} else {
1028		if (bits || !skip_empty)
1029			len += snprintf(buf, buf_size, "%lx", bits);
1030	}
1031
1032	return len;
1033}
1034
1035#else /* !CONFIG_COMPAT */
1036
1037static int input_bits_to_string(char *buf, int buf_size,
1038				unsigned long bits, bool skip_empty)
1039{
1040	return bits || !skip_empty ?
1041		snprintf(buf, buf_size, "%lx", bits) : 0;
1042}
1043
1044#endif
1045
1046#ifdef CONFIG_PROC_FS
1047
1048static struct proc_dir_entry *proc_bus_input_dir;
1049static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
1050static int input_devices_state;
1051
1052static inline void input_wakeup_procfs_readers(void)
1053{
1054	input_devices_state++;
1055	wake_up(&input_devices_poll_wait);
1056}
1057
1058static unsigned int input_proc_devices_poll(struct file *file, poll_table *wait)
1059{
1060	poll_wait(file, &input_devices_poll_wait, wait);
1061	if (file->f_version != input_devices_state) {
1062		file->f_version = input_devices_state;
1063		return POLLIN | POLLRDNORM;
1064	}
1065
1066	return 0;
1067}
1068
1069union input_seq_state {
1070	struct {
1071		unsigned short pos;
1072		bool mutex_acquired;
1073	};
1074	void *p;
1075};
1076
1077static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
1078{
1079	union input_seq_state *state = (union input_seq_state *)&seq->private;
1080	int error;
1081
1082	/* We need to fit into seq->private pointer */
1083	BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1084
1085	error = mutex_lock_interruptible(&input_mutex);
1086	if (error) {
1087		state->mutex_acquired = false;
1088		return ERR_PTR(error);
1089	}
1090
1091	state->mutex_acquired = true;
1092
1093	return seq_list_start(&input_dev_list, *pos);
1094}
1095
1096static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1097{
1098	return seq_list_next(v, &input_dev_list, pos);
1099}
1100
1101static void input_seq_stop(struct seq_file *seq, void *v)
1102{
1103	union input_seq_state *state = (union input_seq_state *)&seq->private;
1104
1105	if (state->mutex_acquired)
1106		mutex_unlock(&input_mutex);
1107}
1108
1109static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
1110				   unsigned long *bitmap, int max)
1111{
1112	int i;
1113	bool skip_empty = true;
1114	char buf[18];
1115
1116	seq_printf(seq, "B: %s=", name);
1117
1118	for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1119		if (input_bits_to_string(buf, sizeof(buf),
1120					 bitmap[i], skip_empty)) {
1121			skip_empty = false;
1122			seq_printf(seq, "%s%s", buf, i > 0 ? " " : "");
1123		}
1124	}
1125
1126	/*
1127	 * If no output was produced print a single 0.
1128	 */
1129	if (skip_empty)
1130		seq_puts(seq, "0");
1131
1132	seq_putc(seq, '\n');
1133}
1134
1135static int input_devices_seq_show(struct seq_file *seq, void *v)
1136{
1137	struct input_dev *dev = container_of(v, struct input_dev, node);
1138	const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1139	struct input_handle *handle;
1140
1141	seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
1142		   dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
1143
1144	seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
1145	seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
1146	seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
1147	seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
1148	seq_printf(seq, "H: Handlers=");
1149
1150	list_for_each_entry(handle, &dev->h_list, d_node)
1151		seq_printf(seq, "%s ", handle->name);
1152	seq_putc(seq, '\n');
1153
1154	input_seq_print_bitmap(seq, "PROP", dev->propbit, INPUT_PROP_MAX);
1155
1156	input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
1157	if (test_bit(EV_KEY, dev->evbit))
1158		input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
1159	if (test_bit(EV_REL, dev->evbit))
1160		input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
1161	if (test_bit(EV_ABS, dev->evbit))
1162		input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
1163	if (test_bit(EV_MSC, dev->evbit))
1164		input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
1165	if (test_bit(EV_LED, dev->evbit))
1166		input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
1167	if (test_bit(EV_SND, dev->evbit))
1168		input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
1169	if (test_bit(EV_FF, dev->evbit))
1170		input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
1171	if (test_bit(EV_SW, dev->evbit))
1172		input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);
1173
1174	seq_putc(seq, '\n');
1175
1176	kfree(path);
1177	return 0;
1178}
1179
1180static const struct seq_operations input_devices_seq_ops = {
1181	.start	= input_devices_seq_start,
1182	.next	= input_devices_seq_next,
1183	.stop	= input_seq_stop,
1184	.show	= input_devices_seq_show,
1185};
1186
1187static int input_proc_devices_open(struct inode *inode, struct file *file)
1188{
1189	return seq_open(file, &input_devices_seq_ops);
1190}
1191
1192static const struct file_operations input_devices_fileops = {
1193	.owner		= THIS_MODULE,
1194	.open		= input_proc_devices_open,
1195	.poll		= input_proc_devices_poll,
1196	.read		= seq_read,
1197	.llseek		= seq_lseek,
1198	.release	= seq_release,
1199};
1200
1201static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
1202{
1203	union input_seq_state *state = (union input_seq_state *)&seq->private;
1204	int error;
1205
1206	/* We need to fit into seq->private pointer */
1207	BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1208
1209	error = mutex_lock_interruptible(&input_mutex);
1210	if (error) {
1211		state->mutex_acquired = false;
1212		return ERR_PTR(error);
1213	}
1214
1215	state->mutex_acquired = true;
1216	state->pos = *pos;
1217
1218	return seq_list_start(&input_handler_list, *pos);
1219}
1220
1221static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1222{
1223	union input_seq_state *state = (union input_seq_state *)&seq->private;
1224
1225	state->pos = *pos + 1;
1226	return seq_list_next(v, &input_handler_list, pos);
1227}
1228
1229static int input_handlers_seq_show(struct seq_file *seq, void *v)
1230{
1231	struct input_handler *handler = container_of(v, struct input_handler, node);
1232	union input_seq_state *state = (union input_seq_state *)&seq->private;
1233
1234	seq_printf(seq, "N: Number=%u Name=%s", state->pos, handler->name);
1235	if (handler->filter)
1236		seq_puts(seq, " (filter)");
1237	if (handler->legacy_minors)
1238		seq_printf(seq, " Minor=%d", handler->minor);
1239	seq_putc(seq, '\n');
1240
1241	return 0;
1242}
1243
1244static const struct seq_operations input_handlers_seq_ops = {
1245	.start	= input_handlers_seq_start,
1246	.next	= input_handlers_seq_next,
1247	.stop	= input_seq_stop,
1248	.show	= input_handlers_seq_show,
1249};
1250
1251static int input_proc_handlers_open(struct inode *inode, struct file *file)
1252{
1253	return seq_open(file, &input_handlers_seq_ops);
1254}
1255
1256static const struct file_operations input_handlers_fileops = {
1257	.owner		= THIS_MODULE,
1258	.open		= input_proc_handlers_open,
1259	.read		= seq_read,
1260	.llseek		= seq_lseek,
1261	.release	= seq_release,
1262};
1263
1264static int __init input_proc_init(void)
1265{
1266	struct proc_dir_entry *entry;
1267
1268	proc_bus_input_dir = proc_mkdir("bus/input", NULL);
1269	if (!proc_bus_input_dir)
1270		return -ENOMEM;
1271
1272	entry = proc_create("devices", 0, proc_bus_input_dir,
1273			    &input_devices_fileops);
1274	if (!entry)
1275		goto fail1;
1276
1277	entry = proc_create("handlers", 0, proc_bus_input_dir,
1278			    &input_handlers_fileops);
1279	if (!entry)
1280		goto fail2;
1281
1282	return 0;
1283
1284 fail2:	remove_proc_entry("devices", proc_bus_input_dir);
1285 fail1: remove_proc_entry("bus/input", NULL);
1286	return -ENOMEM;
1287}
1288
1289static void input_proc_exit(void)
1290{
1291	remove_proc_entry("devices", proc_bus_input_dir);
1292	remove_proc_entry("handlers", proc_bus_input_dir);
1293	remove_proc_entry("bus/input", NULL);
1294}
1295
1296#else /* !CONFIG_PROC_FS */
1297static inline void input_wakeup_procfs_readers(void) { }
1298static inline int input_proc_init(void) { return 0; }
1299static inline void input_proc_exit(void) { }
1300#endif
1301
1302#define INPUT_DEV_STRING_ATTR_SHOW(name)				\
1303static ssize_t input_dev_show_##name(struct device *dev,		\
1304				     struct device_attribute *attr,	\
1305				     char *buf)				\
1306{									\
1307	struct input_dev *input_dev = to_input_dev(dev);		\
1308									\
1309	return scnprintf(buf, PAGE_SIZE, "%s\n",			\
1310			 input_dev->name ? input_dev->name : "");	\
1311}									\
1312static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
1313
1314INPUT_DEV_STRING_ATTR_SHOW(name);
1315INPUT_DEV_STRING_ATTR_SHOW(phys);
1316INPUT_DEV_STRING_ATTR_SHOW(uniq);
1317
1318static int input_print_modalias_bits(char *buf, int size,
1319				     char name, unsigned long *bm,
1320				     unsigned int min_bit, unsigned int max_bit)
1321{
1322	int len = 0, i;
1323
1324	len += snprintf(buf, max(size, 0), "%c", name);
1325	for (i = min_bit; i < max_bit; i++)
1326		if (bm[BIT_WORD(i)] & BIT_MASK(i))
1327			len += snprintf(buf + len, max(size - len, 0), "%X,", i);
1328	return len;
1329}
1330
1331static int input_print_modalias(char *buf, int size, struct input_dev *id,
1332				int add_cr)
1333{
1334	int len;
1335
1336	len = snprintf(buf, max(size, 0),
1337		       "input:b%04Xv%04Xp%04Xe%04X-",
1338		       id->id.bustype, id->id.vendor,
1339		       id->id.product, id->id.version);
1340
1341	len += input_print_modalias_bits(buf + len, size - len,
1342				'e', id->evbit, 0, EV_MAX);
1343	len += input_print_modalias_bits(buf + len, size - len,
1344				'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
1345	len += input_print_modalias_bits(buf + len, size - len,
1346				'r', id->relbit, 0, REL_MAX);
1347	len += input_print_modalias_bits(buf + len, size - len,
1348				'a', id->absbit, 0, ABS_MAX);
1349	len += input_print_modalias_bits(buf + len, size - len,
1350				'm', id->mscbit, 0, MSC_MAX);
1351	len += input_print_modalias_bits(buf + len, size - len,
1352				'l', id->ledbit, 0, LED_MAX);
1353	len += input_print_modalias_bits(buf + len, size - len,
1354				's', id->sndbit, 0, SND_MAX);
1355	len += input_print_modalias_bits(buf + len, size - len,
1356				'f', id->ffbit, 0, FF_MAX);
1357	len += input_print_modalias_bits(buf + len, size - len,
1358				'w', id->swbit, 0, SW_MAX);
1359
1360	if (add_cr)
1361		len += snprintf(buf + len, max(size - len, 0), "\n");
1362
1363	return len;
1364}
1365
1366static ssize_t input_dev_show_modalias(struct device *dev,
1367				       struct device_attribute *attr,
1368				       char *buf)
1369{
1370	struct input_dev *id = to_input_dev(dev);
1371	ssize_t len;
1372
1373	len = input_print_modalias(buf, PAGE_SIZE, id, 1);
1374
1375	return min_t(int, len, PAGE_SIZE);
1376}
1377static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
1378
1379static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1380			      int max, int add_cr);
1381
1382static ssize_t input_dev_show_properties(struct device *dev,
1383					 struct device_attribute *attr,
1384					 char *buf)
1385{
1386	struct input_dev *input_dev = to_input_dev(dev);
1387	int len = input_print_bitmap(buf, PAGE_SIZE, input_dev->propbit,
1388				     INPUT_PROP_MAX, true);
1389	return min_t(int, len, PAGE_SIZE);
1390}
1391static DEVICE_ATTR(properties, S_IRUGO, input_dev_show_properties, NULL);
1392
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1393static struct attribute *input_dev_attrs[] = {
1394	&dev_attr_name.attr,
1395	&dev_attr_phys.attr,
1396	&dev_attr_uniq.attr,
1397	&dev_attr_modalias.attr,
1398	&dev_attr_properties.attr,
 
1399	NULL
1400};
1401
1402static struct attribute_group input_dev_attr_group = {
1403	.attrs	= input_dev_attrs,
1404};
1405
1406#define INPUT_DEV_ID_ATTR(name)						\
1407static ssize_t input_dev_show_id_##name(struct device *dev,		\
1408					struct device_attribute *attr,	\
1409					char *buf)			\
1410{									\
1411	struct input_dev *input_dev = to_input_dev(dev);		\
1412	return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name);	\
1413}									\
1414static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
1415
1416INPUT_DEV_ID_ATTR(bustype);
1417INPUT_DEV_ID_ATTR(vendor);
1418INPUT_DEV_ID_ATTR(product);
1419INPUT_DEV_ID_ATTR(version);
1420
1421static struct attribute *input_dev_id_attrs[] = {
1422	&dev_attr_bustype.attr,
1423	&dev_attr_vendor.attr,
1424	&dev_attr_product.attr,
1425	&dev_attr_version.attr,
1426	NULL
1427};
1428
1429static struct attribute_group input_dev_id_attr_group = {
1430	.name	= "id",
1431	.attrs	= input_dev_id_attrs,
1432};
1433
1434static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1435			      int max, int add_cr)
1436{
1437	int i;
1438	int len = 0;
1439	bool skip_empty = true;
1440
1441	for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1442		len += input_bits_to_string(buf + len, max(buf_size - len, 0),
1443					    bitmap[i], skip_empty);
1444		if (len) {
1445			skip_empty = false;
1446			if (i > 0)
1447				len += snprintf(buf + len, max(buf_size - len, 0), " ");
1448		}
1449	}
1450
1451	/*
1452	 * If no output was produced print a single 0.
1453	 */
1454	if (len == 0)
1455		len = snprintf(buf, buf_size, "%d", 0);
1456
1457	if (add_cr)
1458		len += snprintf(buf + len, max(buf_size - len, 0), "\n");
1459
1460	return len;
1461}
1462
1463#define INPUT_DEV_CAP_ATTR(ev, bm)					\
1464static ssize_t input_dev_show_cap_##bm(struct device *dev,		\
1465				       struct device_attribute *attr,	\
1466				       char *buf)			\
1467{									\
1468	struct input_dev *input_dev = to_input_dev(dev);		\
1469	int len = input_print_bitmap(buf, PAGE_SIZE,			\
1470				     input_dev->bm##bit, ev##_MAX,	\
1471				     true);				\
1472	return min_t(int, len, PAGE_SIZE);				\
1473}									\
1474static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
1475
1476INPUT_DEV_CAP_ATTR(EV, ev);
1477INPUT_DEV_CAP_ATTR(KEY, key);
1478INPUT_DEV_CAP_ATTR(REL, rel);
1479INPUT_DEV_CAP_ATTR(ABS, abs);
1480INPUT_DEV_CAP_ATTR(MSC, msc);
1481INPUT_DEV_CAP_ATTR(LED, led);
1482INPUT_DEV_CAP_ATTR(SND, snd);
1483INPUT_DEV_CAP_ATTR(FF, ff);
1484INPUT_DEV_CAP_ATTR(SW, sw);
1485
1486static struct attribute *input_dev_caps_attrs[] = {
1487	&dev_attr_ev.attr,
1488	&dev_attr_key.attr,
1489	&dev_attr_rel.attr,
1490	&dev_attr_abs.attr,
1491	&dev_attr_msc.attr,
1492	&dev_attr_led.attr,
1493	&dev_attr_snd.attr,
1494	&dev_attr_ff.attr,
1495	&dev_attr_sw.attr,
1496	NULL
1497};
1498
1499static struct attribute_group input_dev_caps_attr_group = {
1500	.name	= "capabilities",
1501	.attrs	= input_dev_caps_attrs,
1502};
1503
1504static const struct attribute_group *input_dev_attr_groups[] = {
1505	&input_dev_attr_group,
1506	&input_dev_id_attr_group,
1507	&input_dev_caps_attr_group,
 
1508	NULL
1509};
1510
1511static void input_dev_release(struct device *device)
1512{
1513	struct input_dev *dev = to_input_dev(device);
1514
1515	input_ff_destroy(dev);
1516	input_mt_destroy_slots(dev);
 
1517	kfree(dev->absinfo);
1518	kfree(dev->vals);
1519	kfree(dev);
1520
1521	module_put(THIS_MODULE);
1522}
1523
1524/*
1525 * Input uevent interface - loading event handlers based on
1526 * device bitfields.
1527 */
1528static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
1529				   const char *name, unsigned long *bitmap, int max)
1530{
1531	int len;
1532
1533	if (add_uevent_var(env, "%s", name))
1534		return -ENOMEM;
1535
1536	len = input_print_bitmap(&env->buf[env->buflen - 1],
1537				 sizeof(env->buf) - env->buflen,
1538				 bitmap, max, false);
1539	if (len >= (sizeof(env->buf) - env->buflen))
1540		return -ENOMEM;
1541
1542	env->buflen += len;
1543	return 0;
1544}
1545
1546static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
1547					 struct input_dev *dev)
1548{
1549	int len;
1550
1551	if (add_uevent_var(env, "MODALIAS="))
1552		return -ENOMEM;
1553
1554	len = input_print_modalias(&env->buf[env->buflen - 1],
1555				   sizeof(env->buf) - env->buflen,
1556				   dev, 0);
1557	if (len >= (sizeof(env->buf) - env->buflen))
1558		return -ENOMEM;
1559
1560	env->buflen += len;
1561	return 0;
1562}
1563
1564#define INPUT_ADD_HOTPLUG_VAR(fmt, val...)				\
1565	do {								\
1566		int err = add_uevent_var(env, fmt, val);		\
1567		if (err)						\
1568			return err;					\
1569	} while (0)
1570
1571#define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max)				\
1572	do {								\
1573		int err = input_add_uevent_bm_var(env, name, bm, max);	\
1574		if (err)						\
1575			return err;					\
1576	} while (0)
1577
1578#define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev)				\
1579	do {								\
1580		int err = input_add_uevent_modalias_var(env, dev);	\
1581		if (err)						\
1582			return err;					\
1583	} while (0)
1584
1585static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
1586{
1587	struct input_dev *dev = to_input_dev(device);
1588
1589	INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
1590				dev->id.bustype, dev->id.vendor,
1591				dev->id.product, dev->id.version);
1592	if (dev->name)
1593		INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
1594	if (dev->phys)
1595		INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
1596	if (dev->uniq)
1597		INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
1598
1599	INPUT_ADD_HOTPLUG_BM_VAR("PROP=", dev->propbit, INPUT_PROP_MAX);
1600
1601	INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
1602	if (test_bit(EV_KEY, dev->evbit))
1603		INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
1604	if (test_bit(EV_REL, dev->evbit))
1605		INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
1606	if (test_bit(EV_ABS, dev->evbit))
1607		INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
1608	if (test_bit(EV_MSC, dev->evbit))
1609		INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
1610	if (test_bit(EV_LED, dev->evbit))
1611		INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
1612	if (test_bit(EV_SND, dev->evbit))
1613		INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
1614	if (test_bit(EV_FF, dev->evbit))
1615		INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
1616	if (test_bit(EV_SW, dev->evbit))
1617		INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
1618
1619	INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
1620
1621	return 0;
1622}
1623
1624#define INPUT_DO_TOGGLE(dev, type, bits, on)				\
1625	do {								\
1626		int i;							\
1627		bool active;						\
1628									\
1629		if (!test_bit(EV_##type, dev->evbit))			\
1630			break;						\
1631									\
1632		for_each_set_bit(i, dev->bits##bit, type##_CNT) {	\
1633			active = test_bit(i, dev->bits);		\
1634			if (!active && !on)				\
1635				continue;				\
1636									\
1637			dev->event(dev, EV_##type, i, on ? active : 0);	\
1638		}							\
1639	} while (0)
1640
1641static void input_dev_toggle(struct input_dev *dev, bool activate)
1642{
1643	if (!dev->event)
1644		return;
1645
1646	INPUT_DO_TOGGLE(dev, LED, led, activate);
1647	INPUT_DO_TOGGLE(dev, SND, snd, activate);
1648
1649	if (activate && test_bit(EV_REP, dev->evbit)) {
1650		dev->event(dev, EV_REP, REP_PERIOD, dev->rep[REP_PERIOD]);
1651		dev->event(dev, EV_REP, REP_DELAY, dev->rep[REP_DELAY]);
1652	}
1653}
1654
1655/**
1656 * input_reset_device() - reset/restore the state of input device
1657 * @dev: input device whose state needs to be reset
1658 *
1659 * This function tries to reset the state of an opened input device and
1660 * bring internal state and state if the hardware in sync with each other.
1661 * We mark all keys as released, restore LED state, repeat rate, etc.
1662 */
1663void input_reset_device(struct input_dev *dev)
1664{
1665	unsigned long flags;
1666
1667	mutex_lock(&dev->mutex);
1668	spin_lock_irqsave(&dev->event_lock, flags);
1669
1670	input_dev_toggle(dev, true);
1671	input_dev_release_keys(dev);
1672
1673	spin_unlock_irqrestore(&dev->event_lock, flags);
1674	mutex_unlock(&dev->mutex);
1675}
1676EXPORT_SYMBOL(input_reset_device);
1677
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1678#ifdef CONFIG_PM_SLEEP
1679static int input_dev_suspend(struct device *dev)
1680{
1681	struct input_dev *input_dev = to_input_dev(dev);
1682
1683	spin_lock_irq(&input_dev->event_lock);
1684
1685	/*
1686	 * Keys that are pressed now are unlikely to be
1687	 * still pressed when we resume.
1688	 */
1689	input_dev_release_keys(input_dev);
1690
1691	/* Turn off LEDs and sounds, if any are active. */
1692	input_dev_toggle(input_dev, false);
1693
1694	spin_unlock_irq(&input_dev->event_lock);
1695
1696	return 0;
1697}
1698
1699static int input_dev_resume(struct device *dev)
1700{
1701	struct input_dev *input_dev = to_input_dev(dev);
1702
1703	spin_lock_irq(&input_dev->event_lock);
1704
1705	/* Restore state of LEDs and sounds, if any were active. */
1706	input_dev_toggle(input_dev, true);
1707
1708	spin_unlock_irq(&input_dev->event_lock);
1709
1710	return 0;
1711}
1712
1713static int input_dev_freeze(struct device *dev)
1714{
1715	struct input_dev *input_dev = to_input_dev(dev);
1716
1717	spin_lock_irq(&input_dev->event_lock);
1718
1719	/*
1720	 * Keys that are pressed now are unlikely to be
1721	 * still pressed when we resume.
1722	 */
1723	input_dev_release_keys(input_dev);
1724
1725	spin_unlock_irq(&input_dev->event_lock);
1726
1727	return 0;
1728}
1729
1730static int input_dev_poweroff(struct device *dev)
1731{
1732	struct input_dev *input_dev = to_input_dev(dev);
1733
1734	spin_lock_irq(&input_dev->event_lock);
1735
1736	/* Turn off LEDs and sounds, if any are active. */
1737	input_dev_toggle(input_dev, false);
1738
1739	spin_unlock_irq(&input_dev->event_lock);
1740
1741	return 0;
1742}
1743
1744static const struct dev_pm_ops input_dev_pm_ops = {
1745	.suspend	= input_dev_suspend,
1746	.resume		= input_dev_resume,
1747	.freeze		= input_dev_freeze,
1748	.poweroff	= input_dev_poweroff,
1749	.restore	= input_dev_resume,
1750};
1751#endif /* CONFIG_PM */
1752
1753static struct device_type input_dev_type = {
1754	.groups		= input_dev_attr_groups,
1755	.release	= input_dev_release,
1756	.uevent		= input_dev_uevent,
1757#ifdef CONFIG_PM_SLEEP
1758	.pm		= &input_dev_pm_ops,
1759#endif
1760};
1761
1762static char *input_devnode(struct device *dev, umode_t *mode)
1763{
1764	return kasprintf(GFP_KERNEL, "input/%s", dev_name(dev));
1765}
1766
1767struct class input_class = {
1768	.name		= "input",
1769	.devnode	= input_devnode,
1770};
1771EXPORT_SYMBOL_GPL(input_class);
1772
1773/**
1774 * input_allocate_device - allocate memory for new input device
1775 *
1776 * Returns prepared struct input_dev or %NULL.
1777 *
1778 * NOTE: Use input_free_device() to free devices that have not been
1779 * registered; input_unregister_device() should be used for already
1780 * registered devices.
1781 */
1782struct input_dev *input_allocate_device(void)
1783{
1784	static atomic_t input_no = ATOMIC_INIT(-1);
1785	struct input_dev *dev;
1786
1787	dev = kzalloc(sizeof(struct input_dev), GFP_KERNEL);
1788	if (dev) {
1789		dev->dev.type = &input_dev_type;
1790		dev->dev.class = &input_class;
1791		device_initialize(&dev->dev);
1792		mutex_init(&dev->mutex);
1793		spin_lock_init(&dev->event_lock);
1794		init_timer(&dev->timer);
1795		INIT_LIST_HEAD(&dev->h_list);
1796		INIT_LIST_HEAD(&dev->node);
1797
1798		dev_set_name(&dev->dev, "input%lu",
1799			     (unsigned long)atomic_inc_return(&input_no));
1800
1801		__module_get(THIS_MODULE);
1802	}
1803
1804	return dev;
1805}
1806EXPORT_SYMBOL(input_allocate_device);
1807
1808struct input_devres {
1809	struct input_dev *input;
1810};
1811
1812static int devm_input_device_match(struct device *dev, void *res, void *data)
1813{
1814	struct input_devres *devres = res;
1815
1816	return devres->input == data;
1817}
1818
1819static void devm_input_device_release(struct device *dev, void *res)
1820{
1821	struct input_devres *devres = res;
1822	struct input_dev *input = devres->input;
1823
1824	dev_dbg(dev, "%s: dropping reference to %s\n",
1825		__func__, dev_name(&input->dev));
1826	input_put_device(input);
1827}
1828
1829/**
1830 * devm_input_allocate_device - allocate managed input device
1831 * @dev: device owning the input device being created
1832 *
1833 * Returns prepared struct input_dev or %NULL.
1834 *
1835 * Managed input devices do not need to be explicitly unregistered or
1836 * freed as it will be done automatically when owner device unbinds from
1837 * its driver (or binding fails). Once managed input device is allocated,
1838 * it is ready to be set up and registered in the same fashion as regular
1839 * input device. There are no special devm_input_device_[un]register()
1840 * variants, regular ones work with both managed and unmanaged devices,
1841 * should you need them. In most cases however, managed input device need
1842 * not be explicitly unregistered or freed.
1843 *
1844 * NOTE: the owner device is set up as parent of input device and users
1845 * should not override it.
1846 */
1847struct input_dev *devm_input_allocate_device(struct device *dev)
1848{
1849	struct input_dev *input;
1850	struct input_devres *devres;
1851
1852	devres = devres_alloc(devm_input_device_release,
1853			      sizeof(struct input_devres), GFP_KERNEL);
1854	if (!devres)
1855		return NULL;
1856
1857	input = input_allocate_device();
1858	if (!input) {
1859		devres_free(devres);
1860		return NULL;
1861	}
1862
1863	input->dev.parent = dev;
1864	input->devres_managed = true;
1865
1866	devres->input = input;
1867	devres_add(dev, devres);
1868
1869	return input;
1870}
1871EXPORT_SYMBOL(devm_input_allocate_device);
1872
1873/**
1874 * input_free_device - free memory occupied by input_dev structure
1875 * @dev: input device to free
1876 *
1877 * This function should only be used if input_register_device()
1878 * was not called yet or if it failed. Once device was registered
1879 * use input_unregister_device() and memory will be freed once last
1880 * reference to the device is dropped.
1881 *
1882 * Device should be allocated by input_allocate_device().
1883 *
1884 * NOTE: If there are references to the input device then memory
1885 * will not be freed until last reference is dropped.
1886 */
1887void input_free_device(struct input_dev *dev)
1888{
1889	if (dev) {
1890		if (dev->devres_managed)
1891			WARN_ON(devres_destroy(dev->dev.parent,
1892						devm_input_device_release,
1893						devm_input_device_match,
1894						dev));
1895		input_put_device(dev);
1896	}
1897}
1898EXPORT_SYMBOL(input_free_device);
1899
1900/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1901 * input_set_capability - mark device as capable of a certain event
1902 * @dev: device that is capable of emitting or accepting event
1903 * @type: type of the event (EV_KEY, EV_REL, etc...)
1904 * @code: event code
1905 *
1906 * In addition to setting up corresponding bit in appropriate capability
1907 * bitmap the function also adjusts dev->evbit.
1908 */
1909void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
1910{
1911	switch (type) {
1912	case EV_KEY:
1913		__set_bit(code, dev->keybit);
1914		break;
1915
1916	case EV_REL:
1917		__set_bit(code, dev->relbit);
1918		break;
1919
1920	case EV_ABS:
1921		input_alloc_absinfo(dev);
1922		if (!dev->absinfo)
1923			return;
1924
1925		__set_bit(code, dev->absbit);
1926		break;
1927
1928	case EV_MSC:
1929		__set_bit(code, dev->mscbit);
1930		break;
1931
1932	case EV_SW:
1933		__set_bit(code, dev->swbit);
1934		break;
1935
1936	case EV_LED:
1937		__set_bit(code, dev->ledbit);
1938		break;
1939
1940	case EV_SND:
1941		__set_bit(code, dev->sndbit);
1942		break;
1943
1944	case EV_FF:
1945		__set_bit(code, dev->ffbit);
1946		break;
1947
1948	case EV_PWR:
1949		/* do nothing */
1950		break;
1951
1952	default:
1953		pr_err("input_set_capability: unknown type %u (code %u)\n",
1954		       type, code);
1955		dump_stack();
1956		return;
1957	}
1958
1959	__set_bit(type, dev->evbit);
1960}
1961EXPORT_SYMBOL(input_set_capability);
1962
1963static unsigned int input_estimate_events_per_packet(struct input_dev *dev)
1964{
1965	int mt_slots;
1966	int i;
1967	unsigned int events;
1968
1969	if (dev->mt) {
1970		mt_slots = dev->mt->num_slots;
1971	} else if (test_bit(ABS_MT_TRACKING_ID, dev->absbit)) {
1972		mt_slots = dev->absinfo[ABS_MT_TRACKING_ID].maximum -
1973			   dev->absinfo[ABS_MT_TRACKING_ID].minimum + 1,
1974		mt_slots = clamp(mt_slots, 2, 32);
1975	} else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
1976		mt_slots = 2;
1977	} else {
1978		mt_slots = 0;
1979	}
1980
1981	events = mt_slots + 1; /* count SYN_MT_REPORT and SYN_REPORT */
1982
1983	if (test_bit(EV_ABS, dev->evbit))
1984		for_each_set_bit(i, dev->absbit, ABS_CNT)
1985			events += input_is_mt_axis(i) ? mt_slots : 1;
1986
1987	if (test_bit(EV_REL, dev->evbit))
1988		events += bitmap_weight(dev->relbit, REL_CNT);
1989
1990	/* Make room for KEY and MSC events */
1991	events += 7;
1992
1993	return events;
1994}
1995
1996#define INPUT_CLEANSE_BITMASK(dev, type, bits)				\
1997	do {								\
1998		if (!test_bit(EV_##type, dev->evbit))			\
1999			memset(dev->bits##bit, 0,			\
2000				sizeof(dev->bits##bit));		\
2001	} while (0)
2002
2003static void input_cleanse_bitmasks(struct input_dev *dev)
2004{
2005	INPUT_CLEANSE_BITMASK(dev, KEY, key);
2006	INPUT_CLEANSE_BITMASK(dev, REL, rel);
2007	INPUT_CLEANSE_BITMASK(dev, ABS, abs);
2008	INPUT_CLEANSE_BITMASK(dev, MSC, msc);
2009	INPUT_CLEANSE_BITMASK(dev, LED, led);
2010	INPUT_CLEANSE_BITMASK(dev, SND, snd);
2011	INPUT_CLEANSE_BITMASK(dev, FF, ff);
2012	INPUT_CLEANSE_BITMASK(dev, SW, sw);
2013}
2014
2015static void __input_unregister_device(struct input_dev *dev)
2016{
2017	struct input_handle *handle, *next;
2018
2019	input_disconnect_device(dev);
2020
2021	mutex_lock(&input_mutex);
2022
2023	list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
2024		handle->handler->disconnect(handle);
2025	WARN_ON(!list_empty(&dev->h_list));
2026
2027	del_timer_sync(&dev->timer);
2028	list_del_init(&dev->node);
2029
2030	input_wakeup_procfs_readers();
2031
2032	mutex_unlock(&input_mutex);
2033
2034	device_del(&dev->dev);
2035}
2036
2037static void devm_input_device_unregister(struct device *dev, void *res)
2038{
2039	struct input_devres *devres = res;
2040	struct input_dev *input = devres->input;
2041
2042	dev_dbg(dev, "%s: unregistering device %s\n",
2043		__func__, dev_name(&input->dev));
2044	__input_unregister_device(input);
2045}
2046
2047/**
2048 * input_enable_softrepeat - enable software autorepeat
2049 * @dev: input device
2050 * @delay: repeat delay
2051 * @period: repeat period
2052 *
2053 * Enable software autorepeat on the input device.
2054 */
2055void input_enable_softrepeat(struct input_dev *dev, int delay, int period)
2056{
2057	dev->timer.data = (unsigned long) dev;
2058	dev->timer.function = input_repeat_key;
2059	dev->rep[REP_DELAY] = delay;
2060	dev->rep[REP_PERIOD] = period;
2061}
2062EXPORT_SYMBOL(input_enable_softrepeat);
2063
 
 
 
 
 
 
 
 
2064/**
2065 * input_register_device - register device with input core
2066 * @dev: device to be registered
2067 *
2068 * This function registers device with input core. The device must be
2069 * allocated with input_allocate_device() and all it's capabilities
2070 * set up before registering.
2071 * If function fails the device must be freed with input_free_device().
2072 * Once device has been successfully registered it can be unregistered
2073 * with input_unregister_device(); input_free_device() should not be
2074 * called in this case.
2075 *
2076 * Note that this function is also used to register managed input devices
2077 * (ones allocated with devm_input_allocate_device()). Such managed input
2078 * devices need not be explicitly unregistered or freed, their tear down
2079 * is controlled by the devres infrastructure. It is also worth noting
2080 * that tear down of managed input devices is internally a 2-step process:
2081 * registered managed input device is first unregistered, but stays in
2082 * memory and can still handle input_event() calls (although events will
2083 * not be delivered anywhere). The freeing of managed input device will
2084 * happen later, when devres stack is unwound to the point where device
2085 * allocation was made.
2086 */
2087int input_register_device(struct input_dev *dev)
2088{
2089	struct input_devres *devres = NULL;
2090	struct input_handler *handler;
2091	unsigned int packet_size;
2092	const char *path;
2093	int error;
2094
 
 
 
 
 
 
2095	if (dev->devres_managed) {
2096		devres = devres_alloc(devm_input_device_unregister,
2097				      sizeof(struct input_devres), GFP_KERNEL);
2098		if (!devres)
2099			return -ENOMEM;
2100
2101		devres->input = dev;
2102	}
2103
2104	/* Every input device generates EV_SYN/SYN_REPORT events. */
2105	__set_bit(EV_SYN, dev->evbit);
2106
2107	/* KEY_RESERVED is not supposed to be transmitted to userspace. */
2108	__clear_bit(KEY_RESERVED, dev->keybit);
2109
2110	/* Make sure that bitmasks not mentioned in dev->evbit are clean. */
2111	input_cleanse_bitmasks(dev);
2112
2113	packet_size = input_estimate_events_per_packet(dev);
2114	if (dev->hint_events_per_packet < packet_size)
2115		dev->hint_events_per_packet = packet_size;
2116
2117	dev->max_vals = dev->hint_events_per_packet + 2;
2118	dev->vals = kcalloc(dev->max_vals, sizeof(*dev->vals), GFP_KERNEL);
2119	if (!dev->vals) {
2120		error = -ENOMEM;
2121		goto err_devres_free;
2122	}
2123
2124	/*
2125	 * If delay and period are pre-set by the driver, then autorepeating
2126	 * is handled by the driver itself and we don't do it in input.c.
2127	 */
2128	if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD])
2129		input_enable_softrepeat(dev, 250, 33);
2130
2131	if (!dev->getkeycode)
2132		dev->getkeycode = input_default_getkeycode;
2133
2134	if (!dev->setkeycode)
2135		dev->setkeycode = input_default_setkeycode;
 
 
 
2136
2137	error = device_add(&dev->dev);
2138	if (error)
2139		goto err_free_vals;
2140
2141	path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
2142	pr_info("%s as %s\n",
2143		dev->name ? dev->name : "Unspecified device",
2144		path ? path : "N/A");
2145	kfree(path);
2146
2147	error = mutex_lock_interruptible(&input_mutex);
2148	if (error)
2149		goto err_device_del;
2150
2151	list_add_tail(&dev->node, &input_dev_list);
2152
2153	list_for_each_entry(handler, &input_handler_list, node)
2154		input_attach_handler(dev, handler);
2155
2156	input_wakeup_procfs_readers();
2157
2158	mutex_unlock(&input_mutex);
2159
2160	if (dev->devres_managed) {
2161		dev_dbg(dev->dev.parent, "%s: registering %s with devres.\n",
2162			__func__, dev_name(&dev->dev));
2163		devres_add(dev->dev.parent, devres);
2164	}
2165	return 0;
2166
2167err_device_del:
2168	device_del(&dev->dev);
2169err_free_vals:
2170	kfree(dev->vals);
2171	dev->vals = NULL;
2172err_devres_free:
2173	devres_free(devres);
2174	return error;
2175}
2176EXPORT_SYMBOL(input_register_device);
2177
2178/**
2179 * input_unregister_device - unregister previously registered device
2180 * @dev: device to be unregistered
2181 *
2182 * This function unregisters an input device. Once device is unregistered
2183 * the caller should not try to access it as it may get freed at any moment.
2184 */
2185void input_unregister_device(struct input_dev *dev)
2186{
2187	if (dev->devres_managed) {
2188		WARN_ON(devres_destroy(dev->dev.parent,
2189					devm_input_device_unregister,
2190					devm_input_device_match,
2191					dev));
2192		__input_unregister_device(dev);
2193		/*
2194		 * We do not do input_put_device() here because it will be done
2195		 * when 2nd devres fires up.
2196		 */
2197	} else {
2198		__input_unregister_device(dev);
2199		input_put_device(dev);
2200	}
2201}
2202EXPORT_SYMBOL(input_unregister_device);
2203
2204/**
2205 * input_register_handler - register a new input handler
2206 * @handler: handler to be registered
2207 *
2208 * This function registers a new input handler (interface) for input
2209 * devices in the system and attaches it to all input devices that
2210 * are compatible with the handler.
2211 */
2212int input_register_handler(struct input_handler *handler)
2213{
2214	struct input_dev *dev;
2215	int error;
2216
2217	error = mutex_lock_interruptible(&input_mutex);
2218	if (error)
2219		return error;
2220
2221	INIT_LIST_HEAD(&handler->h_list);
2222
2223	list_add_tail(&handler->node, &input_handler_list);
2224
2225	list_for_each_entry(dev, &input_dev_list, node)
2226		input_attach_handler(dev, handler);
2227
2228	input_wakeup_procfs_readers();
2229
2230	mutex_unlock(&input_mutex);
2231	return 0;
2232}
2233EXPORT_SYMBOL(input_register_handler);
2234
2235/**
2236 * input_unregister_handler - unregisters an input handler
2237 * @handler: handler to be unregistered
2238 *
2239 * This function disconnects a handler from its input devices and
2240 * removes it from lists of known handlers.
2241 */
2242void input_unregister_handler(struct input_handler *handler)
2243{
2244	struct input_handle *handle, *next;
2245
2246	mutex_lock(&input_mutex);
2247
2248	list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
2249		handler->disconnect(handle);
2250	WARN_ON(!list_empty(&handler->h_list));
2251
2252	list_del_init(&handler->node);
2253
2254	input_wakeup_procfs_readers();
2255
2256	mutex_unlock(&input_mutex);
2257}
2258EXPORT_SYMBOL(input_unregister_handler);
2259
2260/**
2261 * input_handler_for_each_handle - handle iterator
2262 * @handler: input handler to iterate
2263 * @data: data for the callback
2264 * @fn: function to be called for each handle
2265 *
2266 * Iterate over @bus's list of devices, and call @fn for each, passing
2267 * it @data and stop when @fn returns a non-zero value. The function is
2268 * using RCU to traverse the list and therefore may be using in atomic
2269 * contexts. The @fn callback is invoked from RCU critical section and
2270 * thus must not sleep.
2271 */
2272int input_handler_for_each_handle(struct input_handler *handler, void *data,
2273				  int (*fn)(struct input_handle *, void *))
2274{
2275	struct input_handle *handle;
2276	int retval = 0;
2277
2278	rcu_read_lock();
2279
2280	list_for_each_entry_rcu(handle, &handler->h_list, h_node) {
2281		retval = fn(handle, data);
2282		if (retval)
2283			break;
2284	}
2285
2286	rcu_read_unlock();
2287
2288	return retval;
2289}
2290EXPORT_SYMBOL(input_handler_for_each_handle);
2291
2292/**
2293 * input_register_handle - register a new input handle
2294 * @handle: handle to register
2295 *
2296 * This function puts a new input handle onto device's
2297 * and handler's lists so that events can flow through
2298 * it once it is opened using input_open_device().
2299 *
2300 * This function is supposed to be called from handler's
2301 * connect() method.
2302 */
2303int input_register_handle(struct input_handle *handle)
2304{
2305	struct input_handler *handler = handle->handler;
2306	struct input_dev *dev = handle->dev;
2307	int error;
2308
2309	/*
2310	 * We take dev->mutex here to prevent race with
2311	 * input_release_device().
2312	 */
2313	error = mutex_lock_interruptible(&dev->mutex);
2314	if (error)
2315		return error;
2316
2317	/*
2318	 * Filters go to the head of the list, normal handlers
2319	 * to the tail.
2320	 */
2321	if (handler->filter)
2322		list_add_rcu(&handle->d_node, &dev->h_list);
2323	else
2324		list_add_tail_rcu(&handle->d_node, &dev->h_list);
2325
2326	mutex_unlock(&dev->mutex);
2327
2328	/*
2329	 * Since we are supposed to be called from ->connect()
2330	 * which is mutually exclusive with ->disconnect()
2331	 * we can't be racing with input_unregister_handle()
2332	 * and so separate lock is not needed here.
2333	 */
2334	list_add_tail_rcu(&handle->h_node, &handler->h_list);
2335
2336	if (handler->start)
2337		handler->start(handle);
2338
2339	return 0;
2340}
2341EXPORT_SYMBOL(input_register_handle);
2342
2343/**
2344 * input_unregister_handle - unregister an input handle
2345 * @handle: handle to unregister
2346 *
2347 * This function removes input handle from device's
2348 * and handler's lists.
2349 *
2350 * This function is supposed to be called from handler's
2351 * disconnect() method.
2352 */
2353void input_unregister_handle(struct input_handle *handle)
2354{
2355	struct input_dev *dev = handle->dev;
2356
2357	list_del_rcu(&handle->h_node);
2358
2359	/*
2360	 * Take dev->mutex to prevent race with input_release_device().
2361	 */
2362	mutex_lock(&dev->mutex);
2363	list_del_rcu(&handle->d_node);
2364	mutex_unlock(&dev->mutex);
2365
2366	synchronize_rcu();
2367}
2368EXPORT_SYMBOL(input_unregister_handle);
2369
2370/**
2371 * input_get_new_minor - allocates a new input minor number
2372 * @legacy_base: beginning or the legacy range to be searched
2373 * @legacy_num: size of legacy range
2374 * @allow_dynamic: whether we can also take ID from the dynamic range
2375 *
2376 * This function allocates a new device minor for from input major namespace.
2377 * Caller can request legacy minor by specifying @legacy_base and @legacy_num
2378 * parameters and whether ID can be allocated from dynamic range if there are
2379 * no free IDs in legacy range.
2380 */
2381int input_get_new_minor(int legacy_base, unsigned int legacy_num,
2382			bool allow_dynamic)
2383{
2384	/*
2385	 * This function should be called from input handler's ->connect()
2386	 * methods, which are serialized with input_mutex, so no additional
2387	 * locking is needed here.
2388	 */
2389	if (legacy_base >= 0) {
2390		int minor = ida_simple_get(&input_ida,
2391					   legacy_base,
2392					   legacy_base + legacy_num,
2393					   GFP_KERNEL);
2394		if (minor >= 0 || !allow_dynamic)
2395			return minor;
2396	}
2397
2398	return ida_simple_get(&input_ida,
2399			      INPUT_FIRST_DYNAMIC_DEV, INPUT_MAX_CHAR_DEVICES,
2400			      GFP_KERNEL);
2401}
2402EXPORT_SYMBOL(input_get_new_minor);
2403
2404/**
2405 * input_free_minor - release previously allocated minor
2406 * @minor: minor to be released
2407 *
2408 * This function releases previously allocated input minor so that it can be
2409 * reused later.
2410 */
2411void input_free_minor(unsigned int minor)
2412{
2413	ida_simple_remove(&input_ida, minor);
2414}
2415EXPORT_SYMBOL(input_free_minor);
2416
2417static int __init input_init(void)
2418{
2419	int err;
2420
2421	err = class_register(&input_class);
2422	if (err) {
2423		pr_err("unable to register input_dev class\n");
2424		return err;
2425	}
2426
2427	err = input_proc_init();
2428	if (err)
2429		goto fail1;
2430
2431	err = register_chrdev_region(MKDEV(INPUT_MAJOR, 0),
2432				     INPUT_MAX_CHAR_DEVICES, "input");
2433	if (err) {
2434		pr_err("unable to register char major %d", INPUT_MAJOR);
2435		goto fail2;
2436	}
2437
2438	return 0;
2439
2440 fail2:	input_proc_exit();
2441 fail1:	class_unregister(&input_class);
2442	return err;
2443}
2444
2445static void __exit input_exit(void)
2446{
2447	input_proc_exit();
2448	unregister_chrdev_region(MKDEV(INPUT_MAJOR, 0),
2449				 INPUT_MAX_CHAR_DEVICES);
2450	class_unregister(&input_class);
2451}
2452
2453subsys_initcall(input_init);
2454module_exit(input_exit);
v5.14.15
   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/poll.h>
  23#include <linux/device.h>
  24#include <linux/mutex.h>
  25#include <linux/rcupdate.h>
  26#include "input-compat.h"
  27#include "input-poller.h"
  28
  29MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
  30MODULE_DESCRIPTION("Input core");
  31MODULE_LICENSE("GPL");
  32
  33#define INPUT_MAX_CHAR_DEVICES		1024
  34#define INPUT_FIRST_DYNAMIC_DEV		256
  35static DEFINE_IDA(input_ida);
  36
  37static LIST_HEAD(input_dev_list);
  38static LIST_HEAD(input_handler_list);
  39
  40/*
  41 * input_mutex protects access to both input_dev_list and input_handler_list.
  42 * This also causes input_[un]register_device and input_[un]register_handler
  43 * be mutually exclusive which simplifies locking in drivers implementing
  44 * input handlers.
  45 */
  46static DEFINE_MUTEX(input_mutex);
  47
  48static const struct input_value input_value_sync = { EV_SYN, SYN_REPORT, 1 };
  49
  50static inline int is_event_supported(unsigned int code,
  51				     unsigned long *bm, unsigned int max)
  52{
  53	return code <= max && test_bit(code, bm);
  54}
  55
  56static int input_defuzz_abs_event(int value, int old_val, int fuzz)
  57{
  58	if (fuzz) {
  59		if (value > old_val - fuzz / 2 && value < old_val + fuzz / 2)
  60			return old_val;
  61
  62		if (value > old_val - fuzz && value < old_val + fuzz)
  63			return (old_val * 3 + value) / 4;
  64
  65		if (value > old_val - fuzz * 2 && value < old_val + fuzz * 2)
  66			return (old_val + value) / 2;
  67	}
  68
  69	return value;
  70}
  71
  72static void input_start_autorepeat(struct input_dev *dev, int code)
  73{
  74	if (test_bit(EV_REP, dev->evbit) &&
  75	    dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] &&
  76	    dev->timer.function) {
  77		dev->repeat_key = code;
  78		mod_timer(&dev->timer,
  79			  jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
  80	}
  81}
  82
  83static void input_stop_autorepeat(struct input_dev *dev)
  84{
  85	del_timer(&dev->timer);
  86}
  87
  88/*
  89 * Pass event first through all filters and then, if event has not been
  90 * filtered out, through all open handles. This function is called with
  91 * dev->event_lock held and interrupts disabled.
  92 */
  93static unsigned int input_to_handler(struct input_handle *handle,
  94			struct input_value *vals, unsigned int count)
  95{
  96	struct input_handler *handler = handle->handler;
  97	struct input_value *end = vals;
  98	struct input_value *v;
  99
 100	if (handler->filter) {
 101		for (v = vals; v != vals + count; v++) {
 102			if (handler->filter(handle, v->type, v->code, v->value))
 103				continue;
 104			if (end != v)
 105				*end = *v;
 106			end++;
 107		}
 108		count = end - vals;
 109	}
 110
 111	if (!count)
 112		return 0;
 113
 114	if (handler->events)
 115		handler->events(handle, vals, count);
 116	else if (handler->event)
 117		for (v = vals; v != vals + count; v++)
 118			handler->event(handle, v->type, v->code, v->value);
 119
 120	return count;
 121}
 122
 123/*
 124 * Pass values first through all filters and then, if event has not been
 125 * filtered out, through all open handles. This function is called with
 126 * dev->event_lock held and interrupts disabled.
 127 */
 128static void input_pass_values(struct input_dev *dev,
 129			      struct input_value *vals, unsigned int count)
 130{
 131	struct input_handle *handle;
 132	struct input_value *v;
 133
 134	if (!count)
 135		return;
 136
 137	rcu_read_lock();
 138
 139	handle = rcu_dereference(dev->grab);
 140	if (handle) {
 141		count = input_to_handler(handle, vals, count);
 142	} else {
 143		list_for_each_entry_rcu(handle, &dev->h_list, d_node)
 144			if (handle->open) {
 145				count = input_to_handler(handle, vals, count);
 146				if (!count)
 147					break;
 148			}
 149	}
 150
 151	rcu_read_unlock();
 152
 
 
 153	/* trigger auto repeat for key events */
 154	if (test_bit(EV_REP, dev->evbit) && test_bit(EV_KEY, dev->evbit)) {
 155		for (v = vals; v != vals + count; v++) {
 156			if (v->type == EV_KEY && v->value != 2) {
 157				if (v->value)
 158					input_start_autorepeat(dev, v->code);
 159				else
 160					input_stop_autorepeat(dev);
 161			}
 162		}
 163	}
 164}
 165
 166static void input_pass_event(struct input_dev *dev,
 167			     unsigned int type, unsigned int code, int value)
 168{
 169	struct input_value vals[] = { { type, code, value } };
 170
 171	input_pass_values(dev, vals, ARRAY_SIZE(vals));
 172}
 173
 174/*
 175 * Generate software autorepeat event. Note that we take
 176 * dev->event_lock here to avoid racing with input_event
 177 * which may cause keys get "stuck".
 178 */
 179static void input_repeat_key(struct timer_list *t)
 180{
 181	struct input_dev *dev = from_timer(dev, t, timer);
 182	unsigned long flags;
 183
 184	spin_lock_irqsave(&dev->event_lock, flags);
 185
 186	if (test_bit(dev->repeat_key, dev->key) &&
 187	    is_event_supported(dev->repeat_key, dev->keybit, KEY_MAX)) {
 188		struct input_value vals[] =  {
 189			{ EV_KEY, dev->repeat_key, 2 },
 190			input_value_sync
 191		};
 192
 193		input_set_timestamp(dev, ktime_get());
 194		input_pass_values(dev, vals, ARRAY_SIZE(vals));
 195
 196		if (dev->rep[REP_PERIOD])
 197			mod_timer(&dev->timer, jiffies +
 198					msecs_to_jiffies(dev->rep[REP_PERIOD]));
 199	}
 200
 201	spin_unlock_irqrestore(&dev->event_lock, flags);
 202}
 203
 204#define INPUT_IGNORE_EVENT	0
 205#define INPUT_PASS_TO_HANDLERS	1
 206#define INPUT_PASS_TO_DEVICE	2
 207#define INPUT_SLOT		4
 208#define INPUT_FLUSH		8
 209#define INPUT_PASS_TO_ALL	(INPUT_PASS_TO_HANDLERS | INPUT_PASS_TO_DEVICE)
 210
 211static int input_handle_abs_event(struct input_dev *dev,
 212				  unsigned int code, int *pval)
 213{
 214	struct input_mt *mt = dev->mt;
 215	bool is_mt_event;
 216	int *pold;
 217
 218	if (code == ABS_MT_SLOT) {
 219		/*
 220		 * "Stage" the event; we'll flush it later, when we
 221		 * get actual touch data.
 222		 */
 223		if (mt && *pval >= 0 && *pval < mt->num_slots)
 224			mt->slot = *pval;
 225
 226		return INPUT_IGNORE_EVENT;
 227	}
 228
 229	is_mt_event = input_is_mt_value(code);
 230
 231	if (!is_mt_event) {
 232		pold = &dev->absinfo[code].value;
 233	} else if (mt) {
 234		pold = &mt->slots[mt->slot].abs[code - ABS_MT_FIRST];
 235	} else {
 236		/*
 237		 * Bypass filtering for multi-touch events when
 238		 * not employing slots.
 239		 */
 240		pold = NULL;
 241	}
 242
 243	if (pold) {
 244		*pval = input_defuzz_abs_event(*pval, *pold,
 245						dev->absinfo[code].fuzz);
 246		if (*pold == *pval)
 247			return INPUT_IGNORE_EVENT;
 248
 249		*pold = *pval;
 250	}
 251
 252	/* Flush pending "slot" event */
 253	if (is_mt_event && mt && mt->slot != input_abs_get_val(dev, ABS_MT_SLOT)) {
 254		input_abs_set_val(dev, ABS_MT_SLOT, mt->slot);
 255		return INPUT_PASS_TO_HANDLERS | INPUT_SLOT;
 256	}
 257
 258	return INPUT_PASS_TO_HANDLERS;
 259}
 260
 261static int input_get_disposition(struct input_dev *dev,
 262			  unsigned int type, unsigned int code, int *pval)
 263{
 264	int disposition = INPUT_IGNORE_EVENT;
 265	int value = *pval;
 266
 267	switch (type) {
 268
 269	case EV_SYN:
 270		switch (code) {
 271		case SYN_CONFIG:
 272			disposition = INPUT_PASS_TO_ALL;
 273			break;
 274
 275		case SYN_REPORT:
 276			disposition = INPUT_PASS_TO_HANDLERS | INPUT_FLUSH;
 277			break;
 278		case SYN_MT_REPORT:
 279			disposition = INPUT_PASS_TO_HANDLERS;
 280			break;
 281		}
 282		break;
 283
 284	case EV_KEY:
 285		if (is_event_supported(code, dev->keybit, KEY_MAX)) {
 286
 287			/* auto-repeat bypasses state updates */
 288			if (value == 2) {
 289				disposition = INPUT_PASS_TO_HANDLERS;
 290				break;
 291			}
 292
 293			if (!!test_bit(code, dev->key) != !!value) {
 294
 295				__change_bit(code, dev->key);
 296				disposition = INPUT_PASS_TO_HANDLERS;
 297			}
 298		}
 299		break;
 300
 301	case EV_SW:
 302		if (is_event_supported(code, dev->swbit, SW_MAX) &&
 303		    !!test_bit(code, dev->sw) != !!value) {
 304
 305			__change_bit(code, dev->sw);
 306			disposition = INPUT_PASS_TO_HANDLERS;
 307		}
 308		break;
 309
 310	case EV_ABS:
 311		if (is_event_supported(code, dev->absbit, ABS_MAX))
 312			disposition = input_handle_abs_event(dev, code, &value);
 313
 314		break;
 315
 316	case EV_REL:
 317		if (is_event_supported(code, dev->relbit, REL_MAX) && value)
 318			disposition = INPUT_PASS_TO_HANDLERS;
 319
 320		break;
 321
 322	case EV_MSC:
 323		if (is_event_supported(code, dev->mscbit, MSC_MAX))
 324			disposition = INPUT_PASS_TO_ALL;
 325
 326		break;
 327
 328	case EV_LED:
 329		if (is_event_supported(code, dev->ledbit, LED_MAX) &&
 330		    !!test_bit(code, dev->led) != !!value) {
 331
 332			__change_bit(code, dev->led);
 333			disposition = INPUT_PASS_TO_ALL;
 334		}
 335		break;
 336
 337	case EV_SND:
 338		if (is_event_supported(code, dev->sndbit, SND_MAX)) {
 339
 340			if (!!test_bit(code, dev->snd) != !!value)
 341				__change_bit(code, dev->snd);
 342			disposition = INPUT_PASS_TO_ALL;
 343		}
 344		break;
 345
 346	case EV_REP:
 347		if (code <= REP_MAX && value >= 0 && dev->rep[code] != value) {
 348			dev->rep[code] = value;
 349			disposition = INPUT_PASS_TO_ALL;
 350		}
 351		break;
 352
 353	case EV_FF:
 354		if (value >= 0)
 355			disposition = INPUT_PASS_TO_ALL;
 356		break;
 357
 358	case EV_PWR:
 359		disposition = INPUT_PASS_TO_ALL;
 360		break;
 361	}
 362
 363	*pval = value;
 364	return disposition;
 365}
 366
 367static void input_handle_event(struct input_dev *dev,
 368			       unsigned int type, unsigned int code, int value)
 369{
 370	int disposition;
 371
 372	/* filter-out events from inhibited devices */
 373	if (dev->inhibited)
 374		return;
 375
 376	disposition = input_get_disposition(dev, type, code, &value);
 377	if (disposition != INPUT_IGNORE_EVENT && type != EV_SYN)
 378		add_input_randomness(type, code, value);
 379
 380	if ((disposition & INPUT_PASS_TO_DEVICE) && dev->event)
 381		dev->event(dev, type, code, value);
 382
 383	if (!dev->vals)
 384		return;
 385
 386	if (disposition & INPUT_PASS_TO_HANDLERS) {
 387		struct input_value *v;
 388
 389		if (disposition & INPUT_SLOT) {
 390			v = &dev->vals[dev->num_vals++];
 391			v->type = EV_ABS;
 392			v->code = ABS_MT_SLOT;
 393			v->value = dev->mt->slot;
 394		}
 395
 396		v = &dev->vals[dev->num_vals++];
 397		v->type = type;
 398		v->code = code;
 399		v->value = value;
 400	}
 401
 402	if (disposition & INPUT_FLUSH) {
 403		if (dev->num_vals >= 2)
 404			input_pass_values(dev, dev->vals, dev->num_vals);
 405		dev->num_vals = 0;
 406		/*
 407		 * Reset the timestamp on flush so we won't end up
 408		 * with a stale one. Note we only need to reset the
 409		 * monolithic one as we use its presence when deciding
 410		 * whether to generate a synthetic timestamp.
 411		 */
 412		dev->timestamp[INPUT_CLK_MONO] = ktime_set(0, 0);
 413	} else if (dev->num_vals >= dev->max_vals - 2) {
 414		dev->vals[dev->num_vals++] = input_value_sync;
 415		input_pass_values(dev, dev->vals, dev->num_vals);
 416		dev->num_vals = 0;
 417	}
 418
 419}
 420
 421/**
 422 * input_event() - report new input event
 423 * @dev: device that generated the event
 424 * @type: type of the event
 425 * @code: event code
 426 * @value: value of the event
 427 *
 428 * This function should be used by drivers implementing various input
 429 * devices to report input events. See also input_inject_event().
 430 *
 431 * NOTE: input_event() may be safely used right after input device was
 432 * allocated with input_allocate_device(), even before it is registered
 433 * with input_register_device(), but the event will not reach any of the
 434 * input handlers. Such early invocation of input_event() may be used
 435 * to 'seed' initial state of a switch or initial position of absolute
 436 * axis, etc.
 437 */
 438void input_event(struct input_dev *dev,
 439		 unsigned int type, unsigned int code, int value)
 440{
 441	unsigned long flags;
 442
 443	if (is_event_supported(type, dev->evbit, EV_MAX)) {
 444
 445		spin_lock_irqsave(&dev->event_lock, flags);
 446		input_handle_event(dev, type, code, value);
 447		spin_unlock_irqrestore(&dev->event_lock, flags);
 448	}
 449}
 450EXPORT_SYMBOL(input_event);
 451
 452/**
 453 * input_inject_event() - send input event from input handler
 454 * @handle: input handle to send event through
 455 * @type: type of the event
 456 * @code: event code
 457 * @value: value of the event
 458 *
 459 * Similar to input_event() but will ignore event if device is
 460 * "grabbed" and handle injecting event is not the one that owns
 461 * the device.
 462 */
 463void input_inject_event(struct input_handle *handle,
 464			unsigned int type, unsigned int code, int value)
 465{
 466	struct input_dev *dev = handle->dev;
 467	struct input_handle *grab;
 468	unsigned long flags;
 469
 470	if (is_event_supported(type, dev->evbit, EV_MAX)) {
 471		spin_lock_irqsave(&dev->event_lock, flags);
 472
 473		rcu_read_lock();
 474		grab = rcu_dereference(dev->grab);
 475		if (!grab || grab == handle)
 476			input_handle_event(dev, type, code, value);
 477		rcu_read_unlock();
 478
 479		spin_unlock_irqrestore(&dev->event_lock, flags);
 480	}
 481}
 482EXPORT_SYMBOL(input_inject_event);
 483
 484/**
 485 * input_alloc_absinfo - allocates array of input_absinfo structs
 486 * @dev: the input device emitting absolute events
 487 *
 488 * If the absinfo struct the caller asked for is already allocated, this
 489 * functions will not do anything.
 490 */
 491void input_alloc_absinfo(struct input_dev *dev)
 492{
 493	if (dev->absinfo)
 494		return;
 
 495
 496	dev->absinfo = kcalloc(ABS_CNT, sizeof(*dev->absinfo), GFP_KERNEL);
 497	if (!dev->absinfo) {
 498		dev_err(dev->dev.parent ?: &dev->dev,
 499			"%s: unable to allocate memory\n", __func__);
 500		/*
 501		 * We will handle this allocation failure in
 502		 * input_register_device() when we refuse to register input
 503		 * device with ABS bits but without absinfo.
 504		 */
 505	}
 506}
 507EXPORT_SYMBOL(input_alloc_absinfo);
 508
 509void input_set_abs_params(struct input_dev *dev, unsigned int axis,
 510			  int min, int max, int fuzz, int flat)
 511{
 512	struct input_absinfo *absinfo;
 513
 514	input_alloc_absinfo(dev);
 515	if (!dev->absinfo)
 516		return;
 517
 518	absinfo = &dev->absinfo[axis];
 519	absinfo->minimum = min;
 520	absinfo->maximum = max;
 521	absinfo->fuzz = fuzz;
 522	absinfo->flat = flat;
 523
 524	__set_bit(EV_ABS, dev->evbit);
 525	__set_bit(axis, dev->absbit);
 526}
 527EXPORT_SYMBOL(input_set_abs_params);
 528
 529
 530/**
 531 * input_grab_device - grabs device for exclusive use
 532 * @handle: input handle that wants to own the device
 533 *
 534 * When a device is grabbed by an input handle all events generated by
 535 * the device are delivered only to this handle. Also events injected
 536 * by other input handles are ignored while device is grabbed.
 537 */
 538int input_grab_device(struct input_handle *handle)
 539{
 540	struct input_dev *dev = handle->dev;
 541	int retval;
 542
 543	retval = mutex_lock_interruptible(&dev->mutex);
 544	if (retval)
 545		return retval;
 546
 547	if (dev->grab) {
 548		retval = -EBUSY;
 549		goto out;
 550	}
 551
 552	rcu_assign_pointer(dev->grab, handle);
 553
 554 out:
 555	mutex_unlock(&dev->mutex);
 556	return retval;
 557}
 558EXPORT_SYMBOL(input_grab_device);
 559
 560static void __input_release_device(struct input_handle *handle)
 561{
 562	struct input_dev *dev = handle->dev;
 563	struct input_handle *grabber;
 564
 565	grabber = rcu_dereference_protected(dev->grab,
 566					    lockdep_is_held(&dev->mutex));
 567	if (grabber == handle) {
 568		rcu_assign_pointer(dev->grab, NULL);
 569		/* Make sure input_pass_event() notices that grab is gone */
 570		synchronize_rcu();
 571
 572		list_for_each_entry(handle, &dev->h_list, d_node)
 573			if (handle->open && handle->handler->start)
 574				handle->handler->start(handle);
 575	}
 576}
 577
 578/**
 579 * input_release_device - release previously grabbed device
 580 * @handle: input handle that owns the device
 581 *
 582 * Releases previously grabbed device so that other input handles can
 583 * start receiving input events. Upon release all handlers attached
 584 * to the device have their start() method called so they have a change
 585 * to synchronize device state with the rest of the system.
 586 */
 587void input_release_device(struct input_handle *handle)
 588{
 589	struct input_dev *dev = handle->dev;
 590
 591	mutex_lock(&dev->mutex);
 592	__input_release_device(handle);
 593	mutex_unlock(&dev->mutex);
 594}
 595EXPORT_SYMBOL(input_release_device);
 596
 597/**
 598 * input_open_device - open input device
 599 * @handle: handle through which device is being accessed
 600 *
 601 * This function should be called by input handlers when they
 602 * want to start receive events from given input device.
 603 */
 604int input_open_device(struct input_handle *handle)
 605{
 606	struct input_dev *dev = handle->dev;
 607	int retval;
 608
 609	retval = mutex_lock_interruptible(&dev->mutex);
 610	if (retval)
 611		return retval;
 612
 613	if (dev->going_away) {
 614		retval = -ENODEV;
 615		goto out;
 616	}
 617
 618	handle->open++;
 619
 620	if (dev->users++ || dev->inhibited) {
 621		/*
 622		 * Device is already opened and/or inhibited,
 623		 * so we can exit immediately and report success.
 624		 */
 625		goto out;
 626	}
 627
 628	if (dev->open) {
 629		retval = dev->open(dev);
 630		if (retval) {
 631			dev->users--;
 632			handle->open--;
 633			/*
 634			 * Make sure we are not delivering any more events
 635			 * through this handle
 636			 */
 637			synchronize_rcu();
 638			goto out;
 639		}
 640	}
 641
 642	if (dev->poller)
 643		input_dev_poller_start(dev->poller);
 644
 645 out:
 646	mutex_unlock(&dev->mutex);
 647	return retval;
 648}
 649EXPORT_SYMBOL(input_open_device);
 650
 651int input_flush_device(struct input_handle *handle, struct file *file)
 652{
 653	struct input_dev *dev = handle->dev;
 654	int retval;
 655
 656	retval = mutex_lock_interruptible(&dev->mutex);
 657	if (retval)
 658		return retval;
 659
 660	if (dev->flush)
 661		retval = dev->flush(dev, file);
 662
 663	mutex_unlock(&dev->mutex);
 664	return retval;
 665}
 666EXPORT_SYMBOL(input_flush_device);
 667
 668/**
 669 * input_close_device - close input device
 670 * @handle: handle through which device is being accessed
 671 *
 672 * This function should be called by input handlers when they
 673 * want to stop receive events from given input device.
 674 */
 675void input_close_device(struct input_handle *handle)
 676{
 677	struct input_dev *dev = handle->dev;
 678
 679	mutex_lock(&dev->mutex);
 680
 681	__input_release_device(handle);
 682
 683	if (!dev->inhibited && !--dev->users) {
 684		if (dev->poller)
 685			input_dev_poller_stop(dev->poller);
 686		if (dev->close)
 687			dev->close(dev);
 688	}
 689
 690	if (!--handle->open) {
 691		/*
 692		 * synchronize_rcu() makes sure that input_pass_event()
 693		 * completed and that no more input events are delivered
 694		 * through this handle
 695		 */
 696		synchronize_rcu();
 697	}
 698
 699	mutex_unlock(&dev->mutex);
 700}
 701EXPORT_SYMBOL(input_close_device);
 702
 703/*
 704 * Simulate keyup events for all keys that are marked as pressed.
 705 * The function must be called with dev->event_lock held.
 706 */
 707static void input_dev_release_keys(struct input_dev *dev)
 708{
 709	bool need_sync = false;
 710	int code;
 711
 712	if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
 713		for_each_set_bit(code, dev->key, KEY_CNT) {
 714			input_pass_event(dev, EV_KEY, code, 0);
 715			need_sync = true;
 716		}
 717
 718		if (need_sync)
 719			input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
 720
 721		memset(dev->key, 0, sizeof(dev->key));
 722	}
 723}
 724
 725/*
 726 * Prepare device for unregistering
 727 */
 728static void input_disconnect_device(struct input_dev *dev)
 729{
 730	struct input_handle *handle;
 731
 732	/*
 733	 * Mark device as going away. Note that we take dev->mutex here
 734	 * not to protect access to dev->going_away but rather to ensure
 735	 * that there are no threads in the middle of input_open_device()
 736	 */
 737	mutex_lock(&dev->mutex);
 738	dev->going_away = true;
 739	mutex_unlock(&dev->mutex);
 740
 741	spin_lock_irq(&dev->event_lock);
 742
 743	/*
 744	 * Simulate keyup events for all pressed keys so that handlers
 745	 * are not left with "stuck" keys. The driver may continue
 746	 * generate events even after we done here but they will not
 747	 * reach any handlers.
 748	 */
 749	input_dev_release_keys(dev);
 750
 751	list_for_each_entry(handle, &dev->h_list, d_node)
 752		handle->open = 0;
 753
 754	spin_unlock_irq(&dev->event_lock);
 755}
 756
 757/**
 758 * input_scancode_to_scalar() - converts scancode in &struct input_keymap_entry
 759 * @ke: keymap entry containing scancode to be converted.
 760 * @scancode: pointer to the location where converted scancode should
 761 *	be stored.
 762 *
 763 * This function is used to convert scancode stored in &struct keymap_entry
 764 * into scalar form understood by legacy keymap handling methods. These
 765 * methods expect scancodes to be represented as 'unsigned int'.
 766 */
 767int input_scancode_to_scalar(const struct input_keymap_entry *ke,
 768			     unsigned int *scancode)
 769{
 770	switch (ke->len) {
 771	case 1:
 772		*scancode = *((u8 *)ke->scancode);
 773		break;
 774
 775	case 2:
 776		*scancode = *((u16 *)ke->scancode);
 777		break;
 778
 779	case 4:
 780		*scancode = *((u32 *)ke->scancode);
 781		break;
 782
 783	default:
 784		return -EINVAL;
 785	}
 786
 787	return 0;
 788}
 789EXPORT_SYMBOL(input_scancode_to_scalar);
 790
 791/*
 792 * Those routines handle the default case where no [gs]etkeycode() is
 793 * defined. In this case, an array indexed by the scancode is used.
 794 */
 795
 796static unsigned int input_fetch_keycode(struct input_dev *dev,
 797					unsigned int index)
 798{
 799	switch (dev->keycodesize) {
 800	case 1:
 801		return ((u8 *)dev->keycode)[index];
 802
 803	case 2:
 804		return ((u16 *)dev->keycode)[index];
 805
 806	default:
 807		return ((u32 *)dev->keycode)[index];
 808	}
 809}
 810
 811static int input_default_getkeycode(struct input_dev *dev,
 812				    struct input_keymap_entry *ke)
 813{
 814	unsigned int index;
 815	int error;
 816
 817	if (!dev->keycodesize)
 818		return -EINVAL;
 819
 820	if (ke->flags & INPUT_KEYMAP_BY_INDEX)
 821		index = ke->index;
 822	else {
 823		error = input_scancode_to_scalar(ke, &index);
 824		if (error)
 825			return error;
 826	}
 827
 828	if (index >= dev->keycodemax)
 829		return -EINVAL;
 830
 831	ke->keycode = input_fetch_keycode(dev, index);
 832	ke->index = index;
 833	ke->len = sizeof(index);
 834	memcpy(ke->scancode, &index, sizeof(index));
 835
 836	return 0;
 837}
 838
 839static int input_default_setkeycode(struct input_dev *dev,
 840				    const struct input_keymap_entry *ke,
 841				    unsigned int *old_keycode)
 842{
 843	unsigned int index;
 844	int error;
 845	int i;
 846
 847	if (!dev->keycodesize)
 848		return -EINVAL;
 849
 850	if (ke->flags & INPUT_KEYMAP_BY_INDEX) {
 851		index = ke->index;
 852	} else {
 853		error = input_scancode_to_scalar(ke, &index);
 854		if (error)
 855			return error;
 856	}
 857
 858	if (index >= dev->keycodemax)
 859		return -EINVAL;
 860
 861	if (dev->keycodesize < sizeof(ke->keycode) &&
 862			(ke->keycode >> (dev->keycodesize * 8)))
 863		return -EINVAL;
 864
 865	switch (dev->keycodesize) {
 866		case 1: {
 867			u8 *k = (u8 *)dev->keycode;
 868			*old_keycode = k[index];
 869			k[index] = ke->keycode;
 870			break;
 871		}
 872		case 2: {
 873			u16 *k = (u16 *)dev->keycode;
 874			*old_keycode = k[index];
 875			k[index] = ke->keycode;
 876			break;
 877		}
 878		default: {
 879			u32 *k = (u32 *)dev->keycode;
 880			*old_keycode = k[index];
 881			k[index] = ke->keycode;
 882			break;
 883		}
 884	}
 885
 886	if (*old_keycode <= KEY_MAX) {
 887		__clear_bit(*old_keycode, dev->keybit);
 888		for (i = 0; i < dev->keycodemax; i++) {
 889			if (input_fetch_keycode(dev, i) == *old_keycode) {
 890				__set_bit(*old_keycode, dev->keybit);
 891				/* Setting the bit twice is useless, so break */
 892				break;
 893			}
 894		}
 895	}
 896
 897	__set_bit(ke->keycode, dev->keybit);
 898	return 0;
 899}
 900
 901/**
 902 * input_get_keycode - retrieve keycode currently mapped to a given scancode
 903 * @dev: input device which keymap is being queried
 904 * @ke: keymap entry
 905 *
 906 * This function should be called by anyone interested in retrieving current
 907 * keymap. Presently evdev handlers use it.
 908 */
 909int input_get_keycode(struct input_dev *dev, struct input_keymap_entry *ke)
 910{
 911	unsigned long flags;
 912	int retval;
 913
 914	spin_lock_irqsave(&dev->event_lock, flags);
 915	retval = dev->getkeycode(dev, ke);
 916	spin_unlock_irqrestore(&dev->event_lock, flags);
 917
 918	return retval;
 919}
 920EXPORT_SYMBOL(input_get_keycode);
 921
 922/**
 923 * input_set_keycode - attribute a keycode to a given scancode
 924 * @dev: input device which keymap is being updated
 925 * @ke: new keymap entry
 926 *
 927 * This function should be called by anyone needing to update current
 928 * keymap. Presently keyboard and evdev handlers use it.
 929 */
 930int input_set_keycode(struct input_dev *dev,
 931		      const struct input_keymap_entry *ke)
 932{
 933	unsigned long flags;
 934	unsigned int old_keycode;
 935	int retval;
 936
 937	if (ke->keycode > KEY_MAX)
 938		return -EINVAL;
 939
 940	spin_lock_irqsave(&dev->event_lock, flags);
 941
 942	retval = dev->setkeycode(dev, ke, &old_keycode);
 943	if (retval)
 944		goto out;
 945
 946	/* Make sure KEY_RESERVED did not get enabled. */
 947	__clear_bit(KEY_RESERVED, dev->keybit);
 948
 949	/*
 950	 * Simulate keyup event if keycode is not present
 951	 * in the keymap anymore
 952	 */
 953	if (old_keycode > KEY_MAX) {
 954		dev_warn(dev->dev.parent ?: &dev->dev,
 955			 "%s: got too big old keycode %#x\n",
 956			 __func__, old_keycode);
 957	} else if (test_bit(EV_KEY, dev->evbit) &&
 958		   !is_event_supported(old_keycode, dev->keybit, KEY_MAX) &&
 959		   __test_and_clear_bit(old_keycode, dev->key)) {
 960		struct input_value vals[] =  {
 961			{ EV_KEY, old_keycode, 0 },
 962			input_value_sync
 963		};
 964
 965		input_pass_values(dev, vals, ARRAY_SIZE(vals));
 966	}
 967
 968 out:
 969	spin_unlock_irqrestore(&dev->event_lock, flags);
 970
 971	return retval;
 972}
 973EXPORT_SYMBOL(input_set_keycode);
 974
 975bool input_match_device_id(const struct input_dev *dev,
 976			   const struct input_device_id *id)
 977{
 978	if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
 979		if (id->bustype != dev->id.bustype)
 980			return false;
 981
 982	if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
 983		if (id->vendor != dev->id.vendor)
 984			return false;
 985
 986	if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
 987		if (id->product != dev->id.product)
 988			return false;
 989
 990	if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
 991		if (id->version != dev->id.version)
 992			return false;
 993
 994	if (!bitmap_subset(id->evbit, dev->evbit, EV_MAX) ||
 995	    !bitmap_subset(id->keybit, dev->keybit, KEY_MAX) ||
 996	    !bitmap_subset(id->relbit, dev->relbit, REL_MAX) ||
 997	    !bitmap_subset(id->absbit, dev->absbit, ABS_MAX) ||
 998	    !bitmap_subset(id->mscbit, dev->mscbit, MSC_MAX) ||
 999	    !bitmap_subset(id->ledbit, dev->ledbit, LED_MAX) ||
1000	    !bitmap_subset(id->sndbit, dev->sndbit, SND_MAX) ||
1001	    !bitmap_subset(id->ffbit, dev->ffbit, FF_MAX) ||
1002	    !bitmap_subset(id->swbit, dev->swbit, SW_MAX) ||
1003	    !bitmap_subset(id->propbit, dev->propbit, INPUT_PROP_MAX)) {
1004		return false;
1005	}
1006
1007	return true;
1008}
1009EXPORT_SYMBOL(input_match_device_id);
1010
1011static const struct input_device_id *input_match_device(struct input_handler *handler,
1012							struct input_dev *dev)
1013{
1014	const struct input_device_id *id;
1015
1016	for (id = handler->id_table; id->flags || id->driver_info; id++) {
1017		if (input_match_device_id(dev, id) &&
1018		    (!handler->match || handler->match(handler, dev))) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1019			return id;
1020		}
1021	}
1022
1023	return NULL;
1024}
1025
1026static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
1027{
1028	const struct input_device_id *id;
1029	int error;
1030
1031	id = input_match_device(handler, dev);
1032	if (!id)
1033		return -ENODEV;
1034
1035	error = handler->connect(handler, dev, id);
1036	if (error && error != -ENODEV)
1037		pr_err("failed to attach handler %s to device %s, error: %d\n",
1038		       handler->name, kobject_name(&dev->dev.kobj), error);
1039
1040	return error;
1041}
1042
1043#ifdef CONFIG_COMPAT
1044
1045static int input_bits_to_string(char *buf, int buf_size,
1046				unsigned long bits, bool skip_empty)
1047{
1048	int len = 0;
1049
1050	if (in_compat_syscall()) {
1051		u32 dword = bits >> 32;
1052		if (dword || !skip_empty)
1053			len += snprintf(buf, buf_size, "%x ", dword);
1054
1055		dword = bits & 0xffffffffUL;
1056		if (dword || !skip_empty || len)
1057			len += snprintf(buf + len, max(buf_size - len, 0),
1058					"%x", dword);
1059	} else {
1060		if (bits || !skip_empty)
1061			len += snprintf(buf, buf_size, "%lx", bits);
1062	}
1063
1064	return len;
1065}
1066
1067#else /* !CONFIG_COMPAT */
1068
1069static int input_bits_to_string(char *buf, int buf_size,
1070				unsigned long bits, bool skip_empty)
1071{
1072	return bits || !skip_empty ?
1073		snprintf(buf, buf_size, "%lx", bits) : 0;
1074}
1075
1076#endif
1077
1078#ifdef CONFIG_PROC_FS
1079
1080static struct proc_dir_entry *proc_bus_input_dir;
1081static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
1082static int input_devices_state;
1083
1084static inline void input_wakeup_procfs_readers(void)
1085{
1086	input_devices_state++;
1087	wake_up(&input_devices_poll_wait);
1088}
1089
1090static __poll_t input_proc_devices_poll(struct file *file, poll_table *wait)
1091{
1092	poll_wait(file, &input_devices_poll_wait, wait);
1093	if (file->f_version != input_devices_state) {
1094		file->f_version = input_devices_state;
1095		return EPOLLIN | EPOLLRDNORM;
1096	}
1097
1098	return 0;
1099}
1100
1101union input_seq_state {
1102	struct {
1103		unsigned short pos;
1104		bool mutex_acquired;
1105	};
1106	void *p;
1107};
1108
1109static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
1110{
1111	union input_seq_state *state = (union input_seq_state *)&seq->private;
1112	int error;
1113
1114	/* We need to fit into seq->private pointer */
1115	BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1116
1117	error = mutex_lock_interruptible(&input_mutex);
1118	if (error) {
1119		state->mutex_acquired = false;
1120		return ERR_PTR(error);
1121	}
1122
1123	state->mutex_acquired = true;
1124
1125	return seq_list_start(&input_dev_list, *pos);
1126}
1127
1128static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1129{
1130	return seq_list_next(v, &input_dev_list, pos);
1131}
1132
1133static void input_seq_stop(struct seq_file *seq, void *v)
1134{
1135	union input_seq_state *state = (union input_seq_state *)&seq->private;
1136
1137	if (state->mutex_acquired)
1138		mutex_unlock(&input_mutex);
1139}
1140
1141static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
1142				   unsigned long *bitmap, int max)
1143{
1144	int i;
1145	bool skip_empty = true;
1146	char buf[18];
1147
1148	seq_printf(seq, "B: %s=", name);
1149
1150	for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1151		if (input_bits_to_string(buf, sizeof(buf),
1152					 bitmap[i], skip_empty)) {
1153			skip_empty = false;
1154			seq_printf(seq, "%s%s", buf, i > 0 ? " " : "");
1155		}
1156	}
1157
1158	/*
1159	 * If no output was produced print a single 0.
1160	 */
1161	if (skip_empty)
1162		seq_putc(seq, '0');
1163
1164	seq_putc(seq, '\n');
1165}
1166
1167static int input_devices_seq_show(struct seq_file *seq, void *v)
1168{
1169	struct input_dev *dev = container_of(v, struct input_dev, node);
1170	const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1171	struct input_handle *handle;
1172
1173	seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
1174		   dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
1175
1176	seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
1177	seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
1178	seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
1179	seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
1180	seq_puts(seq, "H: Handlers=");
1181
1182	list_for_each_entry(handle, &dev->h_list, d_node)
1183		seq_printf(seq, "%s ", handle->name);
1184	seq_putc(seq, '\n');
1185
1186	input_seq_print_bitmap(seq, "PROP", dev->propbit, INPUT_PROP_MAX);
1187
1188	input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
1189	if (test_bit(EV_KEY, dev->evbit))
1190		input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
1191	if (test_bit(EV_REL, dev->evbit))
1192		input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
1193	if (test_bit(EV_ABS, dev->evbit))
1194		input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
1195	if (test_bit(EV_MSC, dev->evbit))
1196		input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
1197	if (test_bit(EV_LED, dev->evbit))
1198		input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
1199	if (test_bit(EV_SND, dev->evbit))
1200		input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
1201	if (test_bit(EV_FF, dev->evbit))
1202		input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
1203	if (test_bit(EV_SW, dev->evbit))
1204		input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);
1205
1206	seq_putc(seq, '\n');
1207
1208	kfree(path);
1209	return 0;
1210}
1211
1212static const struct seq_operations input_devices_seq_ops = {
1213	.start	= input_devices_seq_start,
1214	.next	= input_devices_seq_next,
1215	.stop	= input_seq_stop,
1216	.show	= input_devices_seq_show,
1217};
1218
1219static int input_proc_devices_open(struct inode *inode, struct file *file)
1220{
1221	return seq_open(file, &input_devices_seq_ops);
1222}
1223
1224static const struct proc_ops input_devices_proc_ops = {
1225	.proc_open	= input_proc_devices_open,
1226	.proc_poll	= input_proc_devices_poll,
1227	.proc_read	= seq_read,
1228	.proc_lseek	= seq_lseek,
1229	.proc_release	= seq_release,
 
1230};
1231
1232static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
1233{
1234	union input_seq_state *state = (union input_seq_state *)&seq->private;
1235	int error;
1236
1237	/* We need to fit into seq->private pointer */
1238	BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1239
1240	error = mutex_lock_interruptible(&input_mutex);
1241	if (error) {
1242		state->mutex_acquired = false;
1243		return ERR_PTR(error);
1244	}
1245
1246	state->mutex_acquired = true;
1247	state->pos = *pos;
1248
1249	return seq_list_start(&input_handler_list, *pos);
1250}
1251
1252static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1253{
1254	union input_seq_state *state = (union input_seq_state *)&seq->private;
1255
1256	state->pos = *pos + 1;
1257	return seq_list_next(v, &input_handler_list, pos);
1258}
1259
1260static int input_handlers_seq_show(struct seq_file *seq, void *v)
1261{
1262	struct input_handler *handler = container_of(v, struct input_handler, node);
1263	union input_seq_state *state = (union input_seq_state *)&seq->private;
1264
1265	seq_printf(seq, "N: Number=%u Name=%s", state->pos, handler->name);
1266	if (handler->filter)
1267		seq_puts(seq, " (filter)");
1268	if (handler->legacy_minors)
1269		seq_printf(seq, " Minor=%d", handler->minor);
1270	seq_putc(seq, '\n');
1271
1272	return 0;
1273}
1274
1275static const struct seq_operations input_handlers_seq_ops = {
1276	.start	= input_handlers_seq_start,
1277	.next	= input_handlers_seq_next,
1278	.stop	= input_seq_stop,
1279	.show	= input_handlers_seq_show,
1280};
1281
1282static int input_proc_handlers_open(struct inode *inode, struct file *file)
1283{
1284	return seq_open(file, &input_handlers_seq_ops);
1285}
1286
1287static const struct proc_ops input_handlers_proc_ops = {
1288	.proc_open	= input_proc_handlers_open,
1289	.proc_read	= seq_read,
1290	.proc_lseek	= seq_lseek,
1291	.proc_release	= seq_release,
 
1292};
1293
1294static int __init input_proc_init(void)
1295{
1296	struct proc_dir_entry *entry;
1297
1298	proc_bus_input_dir = proc_mkdir("bus/input", NULL);
1299	if (!proc_bus_input_dir)
1300		return -ENOMEM;
1301
1302	entry = proc_create("devices", 0, proc_bus_input_dir,
1303			    &input_devices_proc_ops);
1304	if (!entry)
1305		goto fail1;
1306
1307	entry = proc_create("handlers", 0, proc_bus_input_dir,
1308			    &input_handlers_proc_ops);
1309	if (!entry)
1310		goto fail2;
1311
1312	return 0;
1313
1314 fail2:	remove_proc_entry("devices", proc_bus_input_dir);
1315 fail1: remove_proc_entry("bus/input", NULL);
1316	return -ENOMEM;
1317}
1318
1319static void input_proc_exit(void)
1320{
1321	remove_proc_entry("devices", proc_bus_input_dir);
1322	remove_proc_entry("handlers", proc_bus_input_dir);
1323	remove_proc_entry("bus/input", NULL);
1324}
1325
1326#else /* !CONFIG_PROC_FS */
1327static inline void input_wakeup_procfs_readers(void) { }
1328static inline int input_proc_init(void) { return 0; }
1329static inline void input_proc_exit(void) { }
1330#endif
1331
1332#define INPUT_DEV_STRING_ATTR_SHOW(name)				\
1333static ssize_t input_dev_show_##name(struct device *dev,		\
1334				     struct device_attribute *attr,	\
1335				     char *buf)				\
1336{									\
1337	struct input_dev *input_dev = to_input_dev(dev);		\
1338									\
1339	return scnprintf(buf, PAGE_SIZE, "%s\n",			\
1340			 input_dev->name ? input_dev->name : "");	\
1341}									\
1342static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
1343
1344INPUT_DEV_STRING_ATTR_SHOW(name);
1345INPUT_DEV_STRING_ATTR_SHOW(phys);
1346INPUT_DEV_STRING_ATTR_SHOW(uniq);
1347
1348static int input_print_modalias_bits(char *buf, int size,
1349				     char name, unsigned long *bm,
1350				     unsigned int min_bit, unsigned int max_bit)
1351{
1352	int len = 0, i;
1353
1354	len += snprintf(buf, max(size, 0), "%c", name);
1355	for (i = min_bit; i < max_bit; i++)
1356		if (bm[BIT_WORD(i)] & BIT_MASK(i))
1357			len += snprintf(buf + len, max(size - len, 0), "%X,", i);
1358	return len;
1359}
1360
1361static int input_print_modalias(char *buf, int size, struct input_dev *id,
1362				int add_cr)
1363{
1364	int len;
1365
1366	len = snprintf(buf, max(size, 0),
1367		       "input:b%04Xv%04Xp%04Xe%04X-",
1368		       id->id.bustype, id->id.vendor,
1369		       id->id.product, id->id.version);
1370
1371	len += input_print_modalias_bits(buf + len, size - len,
1372				'e', id->evbit, 0, EV_MAX);
1373	len += input_print_modalias_bits(buf + len, size - len,
1374				'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
1375	len += input_print_modalias_bits(buf + len, size - len,
1376				'r', id->relbit, 0, REL_MAX);
1377	len += input_print_modalias_bits(buf + len, size - len,
1378				'a', id->absbit, 0, ABS_MAX);
1379	len += input_print_modalias_bits(buf + len, size - len,
1380				'm', id->mscbit, 0, MSC_MAX);
1381	len += input_print_modalias_bits(buf + len, size - len,
1382				'l', id->ledbit, 0, LED_MAX);
1383	len += input_print_modalias_bits(buf + len, size - len,
1384				's', id->sndbit, 0, SND_MAX);
1385	len += input_print_modalias_bits(buf + len, size - len,
1386				'f', id->ffbit, 0, FF_MAX);
1387	len += input_print_modalias_bits(buf + len, size - len,
1388				'w', id->swbit, 0, SW_MAX);
1389
1390	if (add_cr)
1391		len += snprintf(buf + len, max(size - len, 0), "\n");
1392
1393	return len;
1394}
1395
1396static ssize_t input_dev_show_modalias(struct device *dev,
1397				       struct device_attribute *attr,
1398				       char *buf)
1399{
1400	struct input_dev *id = to_input_dev(dev);
1401	ssize_t len;
1402
1403	len = input_print_modalias(buf, PAGE_SIZE, id, 1);
1404
1405	return min_t(int, len, PAGE_SIZE);
1406}
1407static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
1408
1409static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1410			      int max, int add_cr);
1411
1412static ssize_t input_dev_show_properties(struct device *dev,
1413					 struct device_attribute *attr,
1414					 char *buf)
1415{
1416	struct input_dev *input_dev = to_input_dev(dev);
1417	int len = input_print_bitmap(buf, PAGE_SIZE, input_dev->propbit,
1418				     INPUT_PROP_MAX, true);
1419	return min_t(int, len, PAGE_SIZE);
1420}
1421static DEVICE_ATTR(properties, S_IRUGO, input_dev_show_properties, NULL);
1422
1423static int input_inhibit_device(struct input_dev *dev);
1424static int input_uninhibit_device(struct input_dev *dev);
1425
1426static ssize_t inhibited_show(struct device *dev,
1427			      struct device_attribute *attr,
1428			      char *buf)
1429{
1430	struct input_dev *input_dev = to_input_dev(dev);
1431
1432	return scnprintf(buf, PAGE_SIZE, "%d\n", input_dev->inhibited);
1433}
1434
1435static ssize_t inhibited_store(struct device *dev,
1436			       struct device_attribute *attr, const char *buf,
1437			       size_t len)
1438{
1439	struct input_dev *input_dev = to_input_dev(dev);
1440	ssize_t rv;
1441	bool inhibited;
1442
1443	if (strtobool(buf, &inhibited))
1444		return -EINVAL;
1445
1446	if (inhibited)
1447		rv = input_inhibit_device(input_dev);
1448	else
1449		rv = input_uninhibit_device(input_dev);
1450
1451	if (rv != 0)
1452		return rv;
1453
1454	return len;
1455}
1456
1457static DEVICE_ATTR_RW(inhibited);
1458
1459static struct attribute *input_dev_attrs[] = {
1460	&dev_attr_name.attr,
1461	&dev_attr_phys.attr,
1462	&dev_attr_uniq.attr,
1463	&dev_attr_modalias.attr,
1464	&dev_attr_properties.attr,
1465	&dev_attr_inhibited.attr,
1466	NULL
1467};
1468
1469static const struct attribute_group input_dev_attr_group = {
1470	.attrs	= input_dev_attrs,
1471};
1472
1473#define INPUT_DEV_ID_ATTR(name)						\
1474static ssize_t input_dev_show_id_##name(struct device *dev,		\
1475					struct device_attribute *attr,	\
1476					char *buf)			\
1477{									\
1478	struct input_dev *input_dev = to_input_dev(dev);		\
1479	return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name);	\
1480}									\
1481static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
1482
1483INPUT_DEV_ID_ATTR(bustype);
1484INPUT_DEV_ID_ATTR(vendor);
1485INPUT_DEV_ID_ATTR(product);
1486INPUT_DEV_ID_ATTR(version);
1487
1488static struct attribute *input_dev_id_attrs[] = {
1489	&dev_attr_bustype.attr,
1490	&dev_attr_vendor.attr,
1491	&dev_attr_product.attr,
1492	&dev_attr_version.attr,
1493	NULL
1494};
1495
1496static const struct attribute_group input_dev_id_attr_group = {
1497	.name	= "id",
1498	.attrs	= input_dev_id_attrs,
1499};
1500
1501static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1502			      int max, int add_cr)
1503{
1504	int i;
1505	int len = 0;
1506	bool skip_empty = true;
1507
1508	for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1509		len += input_bits_to_string(buf + len, max(buf_size - len, 0),
1510					    bitmap[i], skip_empty);
1511		if (len) {
1512			skip_empty = false;
1513			if (i > 0)
1514				len += snprintf(buf + len, max(buf_size - len, 0), " ");
1515		}
1516	}
1517
1518	/*
1519	 * If no output was produced print a single 0.
1520	 */
1521	if (len == 0)
1522		len = snprintf(buf, buf_size, "%d", 0);
1523
1524	if (add_cr)
1525		len += snprintf(buf + len, max(buf_size - len, 0), "\n");
1526
1527	return len;
1528}
1529
1530#define INPUT_DEV_CAP_ATTR(ev, bm)					\
1531static ssize_t input_dev_show_cap_##bm(struct device *dev,		\
1532				       struct device_attribute *attr,	\
1533				       char *buf)			\
1534{									\
1535	struct input_dev *input_dev = to_input_dev(dev);		\
1536	int len = input_print_bitmap(buf, PAGE_SIZE,			\
1537				     input_dev->bm##bit, ev##_MAX,	\
1538				     true);				\
1539	return min_t(int, len, PAGE_SIZE);				\
1540}									\
1541static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
1542
1543INPUT_DEV_CAP_ATTR(EV, ev);
1544INPUT_DEV_CAP_ATTR(KEY, key);
1545INPUT_DEV_CAP_ATTR(REL, rel);
1546INPUT_DEV_CAP_ATTR(ABS, abs);
1547INPUT_DEV_CAP_ATTR(MSC, msc);
1548INPUT_DEV_CAP_ATTR(LED, led);
1549INPUT_DEV_CAP_ATTR(SND, snd);
1550INPUT_DEV_CAP_ATTR(FF, ff);
1551INPUT_DEV_CAP_ATTR(SW, sw);
1552
1553static struct attribute *input_dev_caps_attrs[] = {
1554	&dev_attr_ev.attr,
1555	&dev_attr_key.attr,
1556	&dev_attr_rel.attr,
1557	&dev_attr_abs.attr,
1558	&dev_attr_msc.attr,
1559	&dev_attr_led.attr,
1560	&dev_attr_snd.attr,
1561	&dev_attr_ff.attr,
1562	&dev_attr_sw.attr,
1563	NULL
1564};
1565
1566static const struct attribute_group input_dev_caps_attr_group = {
1567	.name	= "capabilities",
1568	.attrs	= input_dev_caps_attrs,
1569};
1570
1571static const struct attribute_group *input_dev_attr_groups[] = {
1572	&input_dev_attr_group,
1573	&input_dev_id_attr_group,
1574	&input_dev_caps_attr_group,
1575	&input_poller_attribute_group,
1576	NULL
1577};
1578
1579static void input_dev_release(struct device *device)
1580{
1581	struct input_dev *dev = to_input_dev(device);
1582
1583	input_ff_destroy(dev);
1584	input_mt_destroy_slots(dev);
1585	kfree(dev->poller);
1586	kfree(dev->absinfo);
1587	kfree(dev->vals);
1588	kfree(dev);
1589
1590	module_put(THIS_MODULE);
1591}
1592
1593/*
1594 * Input uevent interface - loading event handlers based on
1595 * device bitfields.
1596 */
1597static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
1598				   const char *name, unsigned long *bitmap, int max)
1599{
1600	int len;
1601
1602	if (add_uevent_var(env, "%s", name))
1603		return -ENOMEM;
1604
1605	len = input_print_bitmap(&env->buf[env->buflen - 1],
1606				 sizeof(env->buf) - env->buflen,
1607				 bitmap, max, false);
1608	if (len >= (sizeof(env->buf) - env->buflen))
1609		return -ENOMEM;
1610
1611	env->buflen += len;
1612	return 0;
1613}
1614
1615static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
1616					 struct input_dev *dev)
1617{
1618	int len;
1619
1620	if (add_uevent_var(env, "MODALIAS="))
1621		return -ENOMEM;
1622
1623	len = input_print_modalias(&env->buf[env->buflen - 1],
1624				   sizeof(env->buf) - env->buflen,
1625				   dev, 0);
1626	if (len >= (sizeof(env->buf) - env->buflen))
1627		return -ENOMEM;
1628
1629	env->buflen += len;
1630	return 0;
1631}
1632
1633#define INPUT_ADD_HOTPLUG_VAR(fmt, val...)				\
1634	do {								\
1635		int err = add_uevent_var(env, fmt, val);		\
1636		if (err)						\
1637			return err;					\
1638	} while (0)
1639
1640#define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max)				\
1641	do {								\
1642		int err = input_add_uevent_bm_var(env, name, bm, max);	\
1643		if (err)						\
1644			return err;					\
1645	} while (0)
1646
1647#define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev)				\
1648	do {								\
1649		int err = input_add_uevent_modalias_var(env, dev);	\
1650		if (err)						\
1651			return err;					\
1652	} while (0)
1653
1654static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
1655{
1656	struct input_dev *dev = to_input_dev(device);
1657
1658	INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
1659				dev->id.bustype, dev->id.vendor,
1660				dev->id.product, dev->id.version);
1661	if (dev->name)
1662		INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
1663	if (dev->phys)
1664		INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
1665	if (dev->uniq)
1666		INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
1667
1668	INPUT_ADD_HOTPLUG_BM_VAR("PROP=", dev->propbit, INPUT_PROP_MAX);
1669
1670	INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
1671	if (test_bit(EV_KEY, dev->evbit))
1672		INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
1673	if (test_bit(EV_REL, dev->evbit))
1674		INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
1675	if (test_bit(EV_ABS, dev->evbit))
1676		INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
1677	if (test_bit(EV_MSC, dev->evbit))
1678		INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
1679	if (test_bit(EV_LED, dev->evbit))
1680		INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
1681	if (test_bit(EV_SND, dev->evbit))
1682		INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
1683	if (test_bit(EV_FF, dev->evbit))
1684		INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
1685	if (test_bit(EV_SW, dev->evbit))
1686		INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
1687
1688	INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
1689
1690	return 0;
1691}
1692
1693#define INPUT_DO_TOGGLE(dev, type, bits, on)				\
1694	do {								\
1695		int i;							\
1696		bool active;						\
1697									\
1698		if (!test_bit(EV_##type, dev->evbit))			\
1699			break;						\
1700									\
1701		for_each_set_bit(i, dev->bits##bit, type##_CNT) {	\
1702			active = test_bit(i, dev->bits);		\
1703			if (!active && !on)				\
1704				continue;				\
1705									\
1706			dev->event(dev, EV_##type, i, on ? active : 0);	\
1707		}							\
1708	} while (0)
1709
1710static void input_dev_toggle(struct input_dev *dev, bool activate)
1711{
1712	if (!dev->event)
1713		return;
1714
1715	INPUT_DO_TOGGLE(dev, LED, led, activate);
1716	INPUT_DO_TOGGLE(dev, SND, snd, activate);
1717
1718	if (activate && test_bit(EV_REP, dev->evbit)) {
1719		dev->event(dev, EV_REP, REP_PERIOD, dev->rep[REP_PERIOD]);
1720		dev->event(dev, EV_REP, REP_DELAY, dev->rep[REP_DELAY]);
1721	}
1722}
1723
1724/**
1725 * input_reset_device() - reset/restore the state of input device
1726 * @dev: input device whose state needs to be reset
1727 *
1728 * This function tries to reset the state of an opened input device and
1729 * bring internal state and state if the hardware in sync with each other.
1730 * We mark all keys as released, restore LED state, repeat rate, etc.
1731 */
1732void input_reset_device(struct input_dev *dev)
1733{
1734	unsigned long flags;
1735
1736	mutex_lock(&dev->mutex);
1737	spin_lock_irqsave(&dev->event_lock, flags);
1738
1739	input_dev_toggle(dev, true);
1740	input_dev_release_keys(dev);
1741
1742	spin_unlock_irqrestore(&dev->event_lock, flags);
1743	mutex_unlock(&dev->mutex);
1744}
1745EXPORT_SYMBOL(input_reset_device);
1746
1747static int input_inhibit_device(struct input_dev *dev)
1748{
1749	int ret = 0;
1750
1751	mutex_lock(&dev->mutex);
1752
1753	if (dev->inhibited)
1754		goto out;
1755
1756	if (dev->users) {
1757		if (dev->close)
1758			dev->close(dev);
1759		if (dev->poller)
1760			input_dev_poller_stop(dev->poller);
1761	}
1762
1763	spin_lock_irq(&dev->event_lock);
1764	input_dev_release_keys(dev);
1765	input_dev_toggle(dev, false);
1766	spin_unlock_irq(&dev->event_lock);
1767
1768	dev->inhibited = true;
1769
1770out:
1771	mutex_unlock(&dev->mutex);
1772	return ret;
1773}
1774
1775static int input_uninhibit_device(struct input_dev *dev)
1776{
1777	int ret = 0;
1778
1779	mutex_lock(&dev->mutex);
1780
1781	if (!dev->inhibited)
1782		goto out;
1783
1784	if (dev->users) {
1785		if (dev->open) {
1786			ret = dev->open(dev);
1787			if (ret)
1788				goto out;
1789		}
1790		if (dev->poller)
1791			input_dev_poller_start(dev->poller);
1792	}
1793
1794	dev->inhibited = false;
1795	spin_lock_irq(&dev->event_lock);
1796	input_dev_toggle(dev, true);
1797	spin_unlock_irq(&dev->event_lock);
1798
1799out:
1800	mutex_unlock(&dev->mutex);
1801	return ret;
1802}
1803
1804#ifdef CONFIG_PM_SLEEP
1805static int input_dev_suspend(struct device *dev)
1806{
1807	struct input_dev *input_dev = to_input_dev(dev);
1808
1809	spin_lock_irq(&input_dev->event_lock);
1810
1811	/*
1812	 * Keys that are pressed now are unlikely to be
1813	 * still pressed when we resume.
1814	 */
1815	input_dev_release_keys(input_dev);
1816
1817	/* Turn off LEDs and sounds, if any are active. */
1818	input_dev_toggle(input_dev, false);
1819
1820	spin_unlock_irq(&input_dev->event_lock);
1821
1822	return 0;
1823}
1824
1825static int input_dev_resume(struct device *dev)
1826{
1827	struct input_dev *input_dev = to_input_dev(dev);
1828
1829	spin_lock_irq(&input_dev->event_lock);
1830
1831	/* Restore state of LEDs and sounds, if any were active. */
1832	input_dev_toggle(input_dev, true);
1833
1834	spin_unlock_irq(&input_dev->event_lock);
1835
1836	return 0;
1837}
1838
1839static int input_dev_freeze(struct device *dev)
1840{
1841	struct input_dev *input_dev = to_input_dev(dev);
1842
1843	spin_lock_irq(&input_dev->event_lock);
1844
1845	/*
1846	 * Keys that are pressed now are unlikely to be
1847	 * still pressed when we resume.
1848	 */
1849	input_dev_release_keys(input_dev);
1850
1851	spin_unlock_irq(&input_dev->event_lock);
1852
1853	return 0;
1854}
1855
1856static int input_dev_poweroff(struct device *dev)
1857{
1858	struct input_dev *input_dev = to_input_dev(dev);
1859
1860	spin_lock_irq(&input_dev->event_lock);
1861
1862	/* Turn off LEDs and sounds, if any are active. */
1863	input_dev_toggle(input_dev, false);
1864
1865	spin_unlock_irq(&input_dev->event_lock);
1866
1867	return 0;
1868}
1869
1870static const struct dev_pm_ops input_dev_pm_ops = {
1871	.suspend	= input_dev_suspend,
1872	.resume		= input_dev_resume,
1873	.freeze		= input_dev_freeze,
1874	.poweroff	= input_dev_poweroff,
1875	.restore	= input_dev_resume,
1876};
1877#endif /* CONFIG_PM */
1878
1879static const struct device_type input_dev_type = {
1880	.groups		= input_dev_attr_groups,
1881	.release	= input_dev_release,
1882	.uevent		= input_dev_uevent,
1883#ifdef CONFIG_PM_SLEEP
1884	.pm		= &input_dev_pm_ops,
1885#endif
1886};
1887
1888static char *input_devnode(struct device *dev, umode_t *mode)
1889{
1890	return kasprintf(GFP_KERNEL, "input/%s", dev_name(dev));
1891}
1892
1893struct class input_class = {
1894	.name		= "input",
1895	.devnode	= input_devnode,
1896};
1897EXPORT_SYMBOL_GPL(input_class);
1898
1899/**
1900 * input_allocate_device - allocate memory for new input device
1901 *
1902 * Returns prepared struct input_dev or %NULL.
1903 *
1904 * NOTE: Use input_free_device() to free devices that have not been
1905 * registered; input_unregister_device() should be used for already
1906 * registered devices.
1907 */
1908struct input_dev *input_allocate_device(void)
1909{
1910	static atomic_t input_no = ATOMIC_INIT(-1);
1911	struct input_dev *dev;
1912
1913	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1914	if (dev) {
1915		dev->dev.type = &input_dev_type;
1916		dev->dev.class = &input_class;
1917		device_initialize(&dev->dev);
1918		mutex_init(&dev->mutex);
1919		spin_lock_init(&dev->event_lock);
1920		timer_setup(&dev->timer, NULL, 0);
1921		INIT_LIST_HEAD(&dev->h_list);
1922		INIT_LIST_HEAD(&dev->node);
1923
1924		dev_set_name(&dev->dev, "input%lu",
1925			     (unsigned long)atomic_inc_return(&input_no));
1926
1927		__module_get(THIS_MODULE);
1928	}
1929
1930	return dev;
1931}
1932EXPORT_SYMBOL(input_allocate_device);
1933
1934struct input_devres {
1935	struct input_dev *input;
1936};
1937
1938static int devm_input_device_match(struct device *dev, void *res, void *data)
1939{
1940	struct input_devres *devres = res;
1941
1942	return devres->input == data;
1943}
1944
1945static void devm_input_device_release(struct device *dev, void *res)
1946{
1947	struct input_devres *devres = res;
1948	struct input_dev *input = devres->input;
1949
1950	dev_dbg(dev, "%s: dropping reference to %s\n",
1951		__func__, dev_name(&input->dev));
1952	input_put_device(input);
1953}
1954
1955/**
1956 * devm_input_allocate_device - allocate managed input device
1957 * @dev: device owning the input device being created
1958 *
1959 * Returns prepared struct input_dev or %NULL.
1960 *
1961 * Managed input devices do not need to be explicitly unregistered or
1962 * freed as it will be done automatically when owner device unbinds from
1963 * its driver (or binding fails). Once managed input device is allocated,
1964 * it is ready to be set up and registered in the same fashion as regular
1965 * input device. There are no special devm_input_device_[un]register()
1966 * variants, regular ones work with both managed and unmanaged devices,
1967 * should you need them. In most cases however, managed input device need
1968 * not be explicitly unregistered or freed.
1969 *
1970 * NOTE: the owner device is set up as parent of input device and users
1971 * should not override it.
1972 */
1973struct input_dev *devm_input_allocate_device(struct device *dev)
1974{
1975	struct input_dev *input;
1976	struct input_devres *devres;
1977
1978	devres = devres_alloc(devm_input_device_release,
1979			      sizeof(*devres), GFP_KERNEL);
1980	if (!devres)
1981		return NULL;
1982
1983	input = input_allocate_device();
1984	if (!input) {
1985		devres_free(devres);
1986		return NULL;
1987	}
1988
1989	input->dev.parent = dev;
1990	input->devres_managed = true;
1991
1992	devres->input = input;
1993	devres_add(dev, devres);
1994
1995	return input;
1996}
1997EXPORT_SYMBOL(devm_input_allocate_device);
1998
1999/**
2000 * input_free_device - free memory occupied by input_dev structure
2001 * @dev: input device to free
2002 *
2003 * This function should only be used if input_register_device()
2004 * was not called yet or if it failed. Once device was registered
2005 * use input_unregister_device() and memory will be freed once last
2006 * reference to the device is dropped.
2007 *
2008 * Device should be allocated by input_allocate_device().
2009 *
2010 * NOTE: If there are references to the input device then memory
2011 * will not be freed until last reference is dropped.
2012 */
2013void input_free_device(struct input_dev *dev)
2014{
2015	if (dev) {
2016		if (dev->devres_managed)
2017			WARN_ON(devres_destroy(dev->dev.parent,
2018						devm_input_device_release,
2019						devm_input_device_match,
2020						dev));
2021		input_put_device(dev);
2022	}
2023}
2024EXPORT_SYMBOL(input_free_device);
2025
2026/**
2027 * input_set_timestamp - set timestamp for input events
2028 * @dev: input device to set timestamp for
2029 * @timestamp: the time at which the event has occurred
2030 *   in CLOCK_MONOTONIC
2031 *
2032 * This function is intended to provide to the input system a more
2033 * accurate time of when an event actually occurred. The driver should
2034 * call this function as soon as a timestamp is acquired ensuring
2035 * clock conversions in input_set_timestamp are done correctly.
2036 *
2037 * The system entering suspend state between timestamp acquisition and
2038 * calling input_set_timestamp can result in inaccurate conversions.
2039 */
2040void input_set_timestamp(struct input_dev *dev, ktime_t timestamp)
2041{
2042	dev->timestamp[INPUT_CLK_MONO] = timestamp;
2043	dev->timestamp[INPUT_CLK_REAL] = ktime_mono_to_real(timestamp);
2044	dev->timestamp[INPUT_CLK_BOOT] = ktime_mono_to_any(timestamp,
2045							   TK_OFFS_BOOT);
2046}
2047EXPORT_SYMBOL(input_set_timestamp);
2048
2049/**
2050 * input_get_timestamp - get timestamp for input events
2051 * @dev: input device to get timestamp from
2052 *
2053 * A valid timestamp is a timestamp of non-zero value.
2054 */
2055ktime_t *input_get_timestamp(struct input_dev *dev)
2056{
2057	const ktime_t invalid_timestamp = ktime_set(0, 0);
2058
2059	if (!ktime_compare(dev->timestamp[INPUT_CLK_MONO], invalid_timestamp))
2060		input_set_timestamp(dev, ktime_get());
2061
2062	return dev->timestamp;
2063}
2064EXPORT_SYMBOL(input_get_timestamp);
2065
2066/**
2067 * input_set_capability - mark device as capable of a certain event
2068 * @dev: device that is capable of emitting or accepting event
2069 * @type: type of the event (EV_KEY, EV_REL, etc...)
2070 * @code: event code
2071 *
2072 * In addition to setting up corresponding bit in appropriate capability
2073 * bitmap the function also adjusts dev->evbit.
2074 */
2075void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
2076{
2077	switch (type) {
2078	case EV_KEY:
2079		__set_bit(code, dev->keybit);
2080		break;
2081
2082	case EV_REL:
2083		__set_bit(code, dev->relbit);
2084		break;
2085
2086	case EV_ABS:
2087		input_alloc_absinfo(dev);
2088		if (!dev->absinfo)
2089			return;
2090
2091		__set_bit(code, dev->absbit);
2092		break;
2093
2094	case EV_MSC:
2095		__set_bit(code, dev->mscbit);
2096		break;
2097
2098	case EV_SW:
2099		__set_bit(code, dev->swbit);
2100		break;
2101
2102	case EV_LED:
2103		__set_bit(code, dev->ledbit);
2104		break;
2105
2106	case EV_SND:
2107		__set_bit(code, dev->sndbit);
2108		break;
2109
2110	case EV_FF:
2111		__set_bit(code, dev->ffbit);
2112		break;
2113
2114	case EV_PWR:
2115		/* do nothing */
2116		break;
2117
2118	default:
2119		pr_err("%s: unknown type %u (code %u)\n", __func__, type, code);
 
2120		dump_stack();
2121		return;
2122	}
2123
2124	__set_bit(type, dev->evbit);
2125}
2126EXPORT_SYMBOL(input_set_capability);
2127
2128static unsigned int input_estimate_events_per_packet(struct input_dev *dev)
2129{
2130	int mt_slots;
2131	int i;
2132	unsigned int events;
2133
2134	if (dev->mt) {
2135		mt_slots = dev->mt->num_slots;
2136	} else if (test_bit(ABS_MT_TRACKING_ID, dev->absbit)) {
2137		mt_slots = dev->absinfo[ABS_MT_TRACKING_ID].maximum -
2138			   dev->absinfo[ABS_MT_TRACKING_ID].minimum + 1,
2139		mt_slots = clamp(mt_slots, 2, 32);
2140	} else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
2141		mt_slots = 2;
2142	} else {
2143		mt_slots = 0;
2144	}
2145
2146	events = mt_slots + 1; /* count SYN_MT_REPORT and SYN_REPORT */
2147
2148	if (test_bit(EV_ABS, dev->evbit))
2149		for_each_set_bit(i, dev->absbit, ABS_CNT)
2150			events += input_is_mt_axis(i) ? mt_slots : 1;
2151
2152	if (test_bit(EV_REL, dev->evbit))
2153		events += bitmap_weight(dev->relbit, REL_CNT);
2154
2155	/* Make room for KEY and MSC events */
2156	events += 7;
2157
2158	return events;
2159}
2160
2161#define INPUT_CLEANSE_BITMASK(dev, type, bits)				\
2162	do {								\
2163		if (!test_bit(EV_##type, dev->evbit))			\
2164			memset(dev->bits##bit, 0,			\
2165				sizeof(dev->bits##bit));		\
2166	} while (0)
2167
2168static void input_cleanse_bitmasks(struct input_dev *dev)
2169{
2170	INPUT_CLEANSE_BITMASK(dev, KEY, key);
2171	INPUT_CLEANSE_BITMASK(dev, REL, rel);
2172	INPUT_CLEANSE_BITMASK(dev, ABS, abs);
2173	INPUT_CLEANSE_BITMASK(dev, MSC, msc);
2174	INPUT_CLEANSE_BITMASK(dev, LED, led);
2175	INPUT_CLEANSE_BITMASK(dev, SND, snd);
2176	INPUT_CLEANSE_BITMASK(dev, FF, ff);
2177	INPUT_CLEANSE_BITMASK(dev, SW, sw);
2178}
2179
2180static void __input_unregister_device(struct input_dev *dev)
2181{
2182	struct input_handle *handle, *next;
2183
2184	input_disconnect_device(dev);
2185
2186	mutex_lock(&input_mutex);
2187
2188	list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
2189		handle->handler->disconnect(handle);
2190	WARN_ON(!list_empty(&dev->h_list));
2191
2192	del_timer_sync(&dev->timer);
2193	list_del_init(&dev->node);
2194
2195	input_wakeup_procfs_readers();
2196
2197	mutex_unlock(&input_mutex);
2198
2199	device_del(&dev->dev);
2200}
2201
2202static void devm_input_device_unregister(struct device *dev, void *res)
2203{
2204	struct input_devres *devres = res;
2205	struct input_dev *input = devres->input;
2206
2207	dev_dbg(dev, "%s: unregistering device %s\n",
2208		__func__, dev_name(&input->dev));
2209	__input_unregister_device(input);
2210}
2211
2212/**
2213 * input_enable_softrepeat - enable software autorepeat
2214 * @dev: input device
2215 * @delay: repeat delay
2216 * @period: repeat period
2217 *
2218 * Enable software autorepeat on the input device.
2219 */
2220void input_enable_softrepeat(struct input_dev *dev, int delay, int period)
2221{
 
2222	dev->timer.function = input_repeat_key;
2223	dev->rep[REP_DELAY] = delay;
2224	dev->rep[REP_PERIOD] = period;
2225}
2226EXPORT_SYMBOL(input_enable_softrepeat);
2227
2228bool input_device_enabled(struct input_dev *dev)
2229{
2230	lockdep_assert_held(&dev->mutex);
2231
2232	return !dev->inhibited && dev->users > 0;
2233}
2234EXPORT_SYMBOL_GPL(input_device_enabled);
2235
2236/**
2237 * input_register_device - register device with input core
2238 * @dev: device to be registered
2239 *
2240 * This function registers device with input core. The device must be
2241 * allocated with input_allocate_device() and all it's capabilities
2242 * set up before registering.
2243 * If function fails the device must be freed with input_free_device().
2244 * Once device has been successfully registered it can be unregistered
2245 * with input_unregister_device(); input_free_device() should not be
2246 * called in this case.
2247 *
2248 * Note that this function is also used to register managed input devices
2249 * (ones allocated with devm_input_allocate_device()). Such managed input
2250 * devices need not be explicitly unregistered or freed, their tear down
2251 * is controlled by the devres infrastructure. It is also worth noting
2252 * that tear down of managed input devices is internally a 2-step process:
2253 * registered managed input device is first unregistered, but stays in
2254 * memory and can still handle input_event() calls (although events will
2255 * not be delivered anywhere). The freeing of managed input device will
2256 * happen later, when devres stack is unwound to the point where device
2257 * allocation was made.
2258 */
2259int input_register_device(struct input_dev *dev)
2260{
2261	struct input_devres *devres = NULL;
2262	struct input_handler *handler;
2263	unsigned int packet_size;
2264	const char *path;
2265	int error;
2266
2267	if (test_bit(EV_ABS, dev->evbit) && !dev->absinfo) {
2268		dev_err(&dev->dev,
2269			"Absolute device without dev->absinfo, refusing to register\n");
2270		return -EINVAL;
2271	}
2272
2273	if (dev->devres_managed) {
2274		devres = devres_alloc(devm_input_device_unregister,
2275				      sizeof(*devres), GFP_KERNEL);
2276		if (!devres)
2277			return -ENOMEM;
2278
2279		devres->input = dev;
2280	}
2281
2282	/* Every input device generates EV_SYN/SYN_REPORT events. */
2283	__set_bit(EV_SYN, dev->evbit);
2284
2285	/* KEY_RESERVED is not supposed to be transmitted to userspace. */
2286	__clear_bit(KEY_RESERVED, dev->keybit);
2287
2288	/* Make sure that bitmasks not mentioned in dev->evbit are clean. */
2289	input_cleanse_bitmasks(dev);
2290
2291	packet_size = input_estimate_events_per_packet(dev);
2292	if (dev->hint_events_per_packet < packet_size)
2293		dev->hint_events_per_packet = packet_size;
2294
2295	dev->max_vals = dev->hint_events_per_packet + 2;
2296	dev->vals = kcalloc(dev->max_vals, sizeof(*dev->vals), GFP_KERNEL);
2297	if (!dev->vals) {
2298		error = -ENOMEM;
2299		goto err_devres_free;
2300	}
2301
2302	/*
2303	 * If delay and period are pre-set by the driver, then autorepeating
2304	 * is handled by the driver itself and we don't do it in input.c.
2305	 */
2306	if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD])
2307		input_enable_softrepeat(dev, 250, 33);
2308
2309	if (!dev->getkeycode)
2310		dev->getkeycode = input_default_getkeycode;
2311
2312	if (!dev->setkeycode)
2313		dev->setkeycode = input_default_setkeycode;
2314
2315	if (dev->poller)
2316		input_dev_poller_finalize(dev->poller);
2317
2318	error = device_add(&dev->dev);
2319	if (error)
2320		goto err_free_vals;
2321
2322	path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
2323	pr_info("%s as %s\n",
2324		dev->name ? dev->name : "Unspecified device",
2325		path ? path : "N/A");
2326	kfree(path);
2327
2328	error = mutex_lock_interruptible(&input_mutex);
2329	if (error)
2330		goto err_device_del;
2331
2332	list_add_tail(&dev->node, &input_dev_list);
2333
2334	list_for_each_entry(handler, &input_handler_list, node)
2335		input_attach_handler(dev, handler);
2336
2337	input_wakeup_procfs_readers();
2338
2339	mutex_unlock(&input_mutex);
2340
2341	if (dev->devres_managed) {
2342		dev_dbg(dev->dev.parent, "%s: registering %s with devres.\n",
2343			__func__, dev_name(&dev->dev));
2344		devres_add(dev->dev.parent, devres);
2345	}
2346	return 0;
2347
2348err_device_del:
2349	device_del(&dev->dev);
2350err_free_vals:
2351	kfree(dev->vals);
2352	dev->vals = NULL;
2353err_devres_free:
2354	devres_free(devres);
2355	return error;
2356}
2357EXPORT_SYMBOL(input_register_device);
2358
2359/**
2360 * input_unregister_device - unregister previously registered device
2361 * @dev: device to be unregistered
2362 *
2363 * This function unregisters an input device. Once device is unregistered
2364 * the caller should not try to access it as it may get freed at any moment.
2365 */
2366void input_unregister_device(struct input_dev *dev)
2367{
2368	if (dev->devres_managed) {
2369		WARN_ON(devres_destroy(dev->dev.parent,
2370					devm_input_device_unregister,
2371					devm_input_device_match,
2372					dev));
2373		__input_unregister_device(dev);
2374		/*
2375		 * We do not do input_put_device() here because it will be done
2376		 * when 2nd devres fires up.
2377		 */
2378	} else {
2379		__input_unregister_device(dev);
2380		input_put_device(dev);
2381	}
2382}
2383EXPORT_SYMBOL(input_unregister_device);
2384
2385/**
2386 * input_register_handler - register a new input handler
2387 * @handler: handler to be registered
2388 *
2389 * This function registers a new input handler (interface) for input
2390 * devices in the system and attaches it to all input devices that
2391 * are compatible with the handler.
2392 */
2393int input_register_handler(struct input_handler *handler)
2394{
2395	struct input_dev *dev;
2396	int error;
2397
2398	error = mutex_lock_interruptible(&input_mutex);
2399	if (error)
2400		return error;
2401
2402	INIT_LIST_HEAD(&handler->h_list);
2403
2404	list_add_tail(&handler->node, &input_handler_list);
2405
2406	list_for_each_entry(dev, &input_dev_list, node)
2407		input_attach_handler(dev, handler);
2408
2409	input_wakeup_procfs_readers();
2410
2411	mutex_unlock(&input_mutex);
2412	return 0;
2413}
2414EXPORT_SYMBOL(input_register_handler);
2415
2416/**
2417 * input_unregister_handler - unregisters an input handler
2418 * @handler: handler to be unregistered
2419 *
2420 * This function disconnects a handler from its input devices and
2421 * removes it from lists of known handlers.
2422 */
2423void input_unregister_handler(struct input_handler *handler)
2424{
2425	struct input_handle *handle, *next;
2426
2427	mutex_lock(&input_mutex);
2428
2429	list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
2430		handler->disconnect(handle);
2431	WARN_ON(!list_empty(&handler->h_list));
2432
2433	list_del_init(&handler->node);
2434
2435	input_wakeup_procfs_readers();
2436
2437	mutex_unlock(&input_mutex);
2438}
2439EXPORT_SYMBOL(input_unregister_handler);
2440
2441/**
2442 * input_handler_for_each_handle - handle iterator
2443 * @handler: input handler to iterate
2444 * @data: data for the callback
2445 * @fn: function to be called for each handle
2446 *
2447 * Iterate over @bus's list of devices, and call @fn for each, passing
2448 * it @data and stop when @fn returns a non-zero value. The function is
2449 * using RCU to traverse the list and therefore may be using in atomic
2450 * contexts. The @fn callback is invoked from RCU critical section and
2451 * thus must not sleep.
2452 */
2453int input_handler_for_each_handle(struct input_handler *handler, void *data,
2454				  int (*fn)(struct input_handle *, void *))
2455{
2456	struct input_handle *handle;
2457	int retval = 0;
2458
2459	rcu_read_lock();
2460
2461	list_for_each_entry_rcu(handle, &handler->h_list, h_node) {
2462		retval = fn(handle, data);
2463		if (retval)
2464			break;
2465	}
2466
2467	rcu_read_unlock();
2468
2469	return retval;
2470}
2471EXPORT_SYMBOL(input_handler_for_each_handle);
2472
2473/**
2474 * input_register_handle - register a new input handle
2475 * @handle: handle to register
2476 *
2477 * This function puts a new input handle onto device's
2478 * and handler's lists so that events can flow through
2479 * it once it is opened using input_open_device().
2480 *
2481 * This function is supposed to be called from handler's
2482 * connect() method.
2483 */
2484int input_register_handle(struct input_handle *handle)
2485{
2486	struct input_handler *handler = handle->handler;
2487	struct input_dev *dev = handle->dev;
2488	int error;
2489
2490	/*
2491	 * We take dev->mutex here to prevent race with
2492	 * input_release_device().
2493	 */
2494	error = mutex_lock_interruptible(&dev->mutex);
2495	if (error)
2496		return error;
2497
2498	/*
2499	 * Filters go to the head of the list, normal handlers
2500	 * to the tail.
2501	 */
2502	if (handler->filter)
2503		list_add_rcu(&handle->d_node, &dev->h_list);
2504	else
2505		list_add_tail_rcu(&handle->d_node, &dev->h_list);
2506
2507	mutex_unlock(&dev->mutex);
2508
2509	/*
2510	 * Since we are supposed to be called from ->connect()
2511	 * which is mutually exclusive with ->disconnect()
2512	 * we can't be racing with input_unregister_handle()
2513	 * and so separate lock is not needed here.
2514	 */
2515	list_add_tail_rcu(&handle->h_node, &handler->h_list);
2516
2517	if (handler->start)
2518		handler->start(handle);
2519
2520	return 0;
2521}
2522EXPORT_SYMBOL(input_register_handle);
2523
2524/**
2525 * input_unregister_handle - unregister an input handle
2526 * @handle: handle to unregister
2527 *
2528 * This function removes input handle from device's
2529 * and handler's lists.
2530 *
2531 * This function is supposed to be called from handler's
2532 * disconnect() method.
2533 */
2534void input_unregister_handle(struct input_handle *handle)
2535{
2536	struct input_dev *dev = handle->dev;
2537
2538	list_del_rcu(&handle->h_node);
2539
2540	/*
2541	 * Take dev->mutex to prevent race with input_release_device().
2542	 */
2543	mutex_lock(&dev->mutex);
2544	list_del_rcu(&handle->d_node);
2545	mutex_unlock(&dev->mutex);
2546
2547	synchronize_rcu();
2548}
2549EXPORT_SYMBOL(input_unregister_handle);
2550
2551/**
2552 * input_get_new_minor - allocates a new input minor number
2553 * @legacy_base: beginning or the legacy range to be searched
2554 * @legacy_num: size of legacy range
2555 * @allow_dynamic: whether we can also take ID from the dynamic range
2556 *
2557 * This function allocates a new device minor for from input major namespace.
2558 * Caller can request legacy minor by specifying @legacy_base and @legacy_num
2559 * parameters and whether ID can be allocated from dynamic range if there are
2560 * no free IDs in legacy range.
2561 */
2562int input_get_new_minor(int legacy_base, unsigned int legacy_num,
2563			bool allow_dynamic)
2564{
2565	/*
2566	 * This function should be called from input handler's ->connect()
2567	 * methods, which are serialized with input_mutex, so no additional
2568	 * locking is needed here.
2569	 */
2570	if (legacy_base >= 0) {
2571		int minor = ida_simple_get(&input_ida,
2572					   legacy_base,
2573					   legacy_base + legacy_num,
2574					   GFP_KERNEL);
2575		if (minor >= 0 || !allow_dynamic)
2576			return minor;
2577	}
2578
2579	return ida_simple_get(&input_ida,
2580			      INPUT_FIRST_DYNAMIC_DEV, INPUT_MAX_CHAR_DEVICES,
2581			      GFP_KERNEL);
2582}
2583EXPORT_SYMBOL(input_get_new_minor);
2584
2585/**
2586 * input_free_minor - release previously allocated minor
2587 * @minor: minor to be released
2588 *
2589 * This function releases previously allocated input minor so that it can be
2590 * reused later.
2591 */
2592void input_free_minor(unsigned int minor)
2593{
2594	ida_simple_remove(&input_ida, minor);
2595}
2596EXPORT_SYMBOL(input_free_minor);
2597
2598static int __init input_init(void)
2599{
2600	int err;
2601
2602	err = class_register(&input_class);
2603	if (err) {
2604		pr_err("unable to register input_dev class\n");
2605		return err;
2606	}
2607
2608	err = input_proc_init();
2609	if (err)
2610		goto fail1;
2611
2612	err = register_chrdev_region(MKDEV(INPUT_MAJOR, 0),
2613				     INPUT_MAX_CHAR_DEVICES, "input");
2614	if (err) {
2615		pr_err("unable to register char major %d", INPUT_MAJOR);
2616		goto fail2;
2617	}
2618
2619	return 0;
2620
2621 fail2:	input_proc_exit();
2622 fail1:	class_unregister(&input_class);
2623	return err;
2624}
2625
2626static void __exit input_exit(void)
2627{
2628	input_proc_exit();
2629	unregister_chrdev_region(MKDEV(INPUT_MAJOR, 0),
2630				 INPUT_MAX_CHAR_DEVICES);
2631	class_unregister(&input_class);
2632}
2633
2634subsys_initcall(input_init);
2635module_exit(input_exit);