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);