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/input/mt.h>
  18#include <linux/module.h>
  19#include <linux/slab.h>
  20#include <linux/random.h>
  21#include <linux/major.h>
  22#include <linux/proc_fs.h>
  23#include <linux/sched.h>
  24#include <linux/seq_file.h>
  25#include <linux/poll.h>
  26#include <linux/device.h>
  27#include <linux/mutex.h>
  28#include <linux/rcupdate.h>
  29#include "input-compat.h"
 
  30
  31MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
  32MODULE_DESCRIPTION("Input core");
  33MODULE_LICENSE("GPL");
  34
  35#define INPUT_DEVICES	256
 
 
  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 struct input_handler *input_table[8];
  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
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  72/*
  73 * Pass event first through all filters and then, if event has not been
  74 * filtered out, through all open handles. This function is called with
  75 * dev->event_lock held and interrupts disabled.
  76 */
  77static void input_pass_event(struct input_dev *dev,
  78			     unsigned int type, unsigned int code, int value)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  79{
  80	struct input_handler *handler;
  81	struct input_handle *handle;
 
 
 
 
  82
  83	rcu_read_lock();
  84
  85	handle = rcu_dereference(dev->grab);
  86	if (handle)
  87		handle->handler->event(handle, type, code, value);
  88	else {
  89		bool filtered = false;
  90
  91		list_for_each_entry_rcu(handle, &dev->h_list, d_node) {
  92			if (!handle->open)
  93				continue;
  94
  95			handler = handle->handler;
  96			if (!handler->filter) {
  97				if (filtered)
  98					break;
 
 
  99
 100				handler->event(handle, type, code, value);
 101
 102			} else if (handler->filter(handle, type, code, value))
 103				filtered = true;
 
 
 
 
 
 
 
 104		}
 105	}
 
 106
 107	rcu_read_unlock();
 
 
 
 
 
 108}
 109
 110/*
 111 * Generate software autorepeat event. Note that we take
 112 * dev->event_lock here to avoid racing with input_event
 113 * which may cause keys get "stuck".
 114 */
 115static void input_repeat_key(unsigned long data)
 116{
 117	struct input_dev *dev = (void *) data;
 118	unsigned long flags;
 119
 120	spin_lock_irqsave(&dev->event_lock, flags);
 121
 122	if (test_bit(dev->repeat_key, dev->key) &&
 123	    is_event_supported(dev->repeat_key, dev->keybit, KEY_MAX)) {
 
 
 
 
 124
 125		input_pass_event(dev, EV_KEY, dev->repeat_key, 2);
 126
 127		if (dev->sync) {
 128			/*
 129			 * Only send SYN_REPORT if we are not in a middle
 130			 * of driver parsing a new hardware packet.
 131			 * Otherwise assume that the driver will send
 132			 * SYN_REPORT once it's done.
 133			 */
 134			input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
 135		}
 136
 137		if (dev->rep[REP_PERIOD])
 138			mod_timer(&dev->timer, jiffies +
 139					msecs_to_jiffies(dev->rep[REP_PERIOD]));
 140	}
 141
 142	spin_unlock_irqrestore(&dev->event_lock, flags);
 143}
 144
 145static void input_start_autorepeat(struct input_dev *dev, int code)
 146{
 147	if (test_bit(EV_REP, dev->evbit) &&
 148	    dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] &&
 149	    dev->timer.data) {
 150		dev->repeat_key = code;
 151		mod_timer(&dev->timer,
 152			  jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
 153	}
 154}
 155
 156static void input_stop_autorepeat(struct input_dev *dev)
 157{
 158	del_timer(&dev->timer);
 159}
 160
 161#define INPUT_IGNORE_EVENT	0
 162#define INPUT_PASS_TO_HANDLERS	1
 163#define INPUT_PASS_TO_DEVICE	2
 
 
 164#define INPUT_PASS_TO_ALL	(INPUT_PASS_TO_HANDLERS | INPUT_PASS_TO_DEVICE)
 165
 166static int input_handle_abs_event(struct input_dev *dev,
 167				  unsigned int code, int *pval)
 168{
 
 169	bool is_mt_event;
 170	int *pold;
 171
 172	if (code == ABS_MT_SLOT) {
 173		/*
 174		 * "Stage" the event; we'll flush it later, when we
 175		 * get actual touch data.
 176		 */
 177		if (*pval >= 0 && *pval < dev->mtsize)
 178			dev->slot = *pval;
 179
 180		return INPUT_IGNORE_EVENT;
 181	}
 182
 183	is_mt_event = code >= ABS_MT_FIRST && code <= ABS_MT_LAST;
 184
 185	if (!is_mt_event) {
 186		pold = &dev->absinfo[code].value;
 187	} else if (dev->mt) {
 188		struct input_mt_slot *mtslot = &dev->mt[dev->slot];
 189		pold = &mtslot->abs[code - ABS_MT_FIRST];
 190	} else {
 191		/*
 192		 * Bypass filtering for multi-touch events when
 193		 * not employing slots.
 194		 */
 195		pold = NULL;
 196	}
 197
 198	if (pold) {
 199		*pval = input_defuzz_abs_event(*pval, *pold,
 200						dev->absinfo[code].fuzz);
 201		if (*pold == *pval)
 202			return INPUT_IGNORE_EVENT;
 203
 204		*pold = *pval;
 205	}
 206
 207	/* Flush pending "slot" event */
 208	if (is_mt_event && dev->slot != input_abs_get_val(dev, ABS_MT_SLOT)) {
 209		input_abs_set_val(dev, ABS_MT_SLOT, dev->slot);
 210		input_pass_event(dev, EV_ABS, ABS_MT_SLOT, dev->slot);
 211	}
 212
 213	return INPUT_PASS_TO_HANDLERS;
 214}
 215
 216static void input_handle_event(struct input_dev *dev,
 217			       unsigned int type, unsigned int code, int value)
 218{
 219	int disposition = INPUT_IGNORE_EVENT;
 
 220
 221	switch (type) {
 222
 223	case EV_SYN:
 224		switch (code) {
 225		case SYN_CONFIG:
 226			disposition = INPUT_PASS_TO_ALL;
 227			break;
 228
 229		case SYN_REPORT:
 230			if (!dev->sync) {
 231				dev->sync = true;
 232				disposition = INPUT_PASS_TO_HANDLERS;
 233			}
 234			break;
 235		case SYN_MT_REPORT:
 236			dev->sync = false;
 237			disposition = INPUT_PASS_TO_HANDLERS;
 238			break;
 239		}
 240		break;
 241
 242	case EV_KEY:
 243		if (is_event_supported(code, dev->keybit, KEY_MAX) &&
 244		    !!test_bit(code, dev->key) != value) {
 245
 246			if (value != 2) {
 247				__change_bit(code, dev->key);
 248				if (value)
 249					input_start_autorepeat(dev, code);
 250				else
 251					input_stop_autorepeat(dev);
 252			}
 253
 254			disposition = INPUT_PASS_TO_HANDLERS;
 
 
 
 
 255		}
 256		break;
 257
 258	case EV_SW:
 259		if (is_event_supported(code, dev->swbit, SW_MAX) &&
 260		    !!test_bit(code, dev->sw) != value) {
 261
 262			__change_bit(code, dev->sw);
 263			disposition = INPUT_PASS_TO_HANDLERS;
 264		}
 265		break;
 266
 267	case EV_ABS:
 268		if (is_event_supported(code, dev->absbit, ABS_MAX))
 269			disposition = input_handle_abs_event(dev, code, &value);
 270
 271		break;
 272
 273	case EV_REL:
 274		if (is_event_supported(code, dev->relbit, REL_MAX) && value)
 275			disposition = INPUT_PASS_TO_HANDLERS;
 276
 277		break;
 278
 279	case EV_MSC:
 280		if (is_event_supported(code, dev->mscbit, MSC_MAX))
 281			disposition = INPUT_PASS_TO_ALL;
 282
 283		break;
 284
 285	case EV_LED:
 286		if (is_event_supported(code, dev->ledbit, LED_MAX) &&
 287		    !!test_bit(code, dev->led) != value) {
 288
 289			__change_bit(code, dev->led);
 290			disposition = INPUT_PASS_TO_ALL;
 291		}
 292		break;
 293
 294	case EV_SND:
 295		if (is_event_supported(code, dev->sndbit, SND_MAX)) {
 296
 297			if (!!test_bit(code, dev->snd) != !!value)
 298				__change_bit(code, dev->snd);
 299			disposition = INPUT_PASS_TO_ALL;
 300		}
 301		break;
 302
 303	case EV_REP:
 304		if (code <= REP_MAX && value >= 0 && dev->rep[code] != value) {
 305			dev->rep[code] = value;
 306			disposition = INPUT_PASS_TO_ALL;
 307		}
 308		break;
 309
 310	case EV_FF:
 311		if (value >= 0)
 312			disposition = INPUT_PASS_TO_ALL;
 313		break;
 314
 315	case EV_PWR:
 316		disposition = INPUT_PASS_TO_ALL;
 317		break;
 318	}
 319
 
 
 
 
 
 
 
 
 
 320	if (disposition != INPUT_IGNORE_EVENT && type != EV_SYN)
 321		dev->sync = false;
 322
 323	if ((disposition & INPUT_PASS_TO_DEVICE) && dev->event)
 324		dev->event(dev, type, code, value);
 325
 326	if (disposition & INPUT_PASS_TO_HANDLERS)
 327		input_pass_event(dev, type, code, value);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 328}
 329
 330/**
 331 * input_event() - report new input event
 332 * @dev: device that generated the event
 333 * @type: type of the event
 334 * @code: event code
 335 * @value: value of the event
 336 *
 337 * This function should be used by drivers implementing various input
 338 * devices to report input events. See also input_inject_event().
 339 *
 340 * NOTE: input_event() may be safely used right after input device was
 341 * allocated with input_allocate_device(), even before it is registered
 342 * with input_register_device(), but the event will not reach any of the
 343 * input handlers. Such early invocation of input_event() may be used
 344 * to 'seed' initial state of a switch or initial position of absolute
 345 * axis, etc.
 346 */
 347void input_event(struct input_dev *dev,
 348		 unsigned int type, unsigned int code, int value)
 349{
 350	unsigned long flags;
 351
 352	if (is_event_supported(type, dev->evbit, EV_MAX)) {
 353
 354		spin_lock_irqsave(&dev->event_lock, flags);
 355		add_input_randomness(type, code, value);
 356		input_handle_event(dev, type, code, value);
 357		spin_unlock_irqrestore(&dev->event_lock, flags);
 358	}
 359}
 360EXPORT_SYMBOL(input_event);
 361
 362/**
 363 * input_inject_event() - send input event from input handler
 364 * @handle: input handle to send event through
 365 * @type: type of the event
 366 * @code: event code
 367 * @value: value of the event
 368 *
 369 * Similar to input_event() but will ignore event if device is
 370 * "grabbed" and handle injecting event is not the one that owns
 371 * the device.
 372 */
 373void input_inject_event(struct input_handle *handle,
 374			unsigned int type, unsigned int code, int value)
 375{
 376	struct input_dev *dev = handle->dev;
 377	struct input_handle *grab;
 378	unsigned long flags;
 379
 380	if (is_event_supported(type, dev->evbit, EV_MAX)) {
 381		spin_lock_irqsave(&dev->event_lock, flags);
 382
 383		rcu_read_lock();
 384		grab = rcu_dereference(dev->grab);
 385		if (!grab || grab == handle)
 386			input_handle_event(dev, type, code, value);
 387		rcu_read_unlock();
 388
 389		spin_unlock_irqrestore(&dev->event_lock, flags);
 390	}
 391}
 392EXPORT_SYMBOL(input_inject_event);
 393
 394/**
 395 * input_alloc_absinfo - allocates array of input_absinfo structs
 396 * @dev: the input device emitting absolute events
 397 *
 398 * If the absinfo struct the caller asked for is already allocated, this
 399 * functions will not do anything.
 400 */
 401void input_alloc_absinfo(struct input_dev *dev)
 402{
 403	if (!dev->absinfo)
 404		dev->absinfo = kcalloc(ABS_CNT, sizeof(struct input_absinfo),
 405					GFP_KERNEL);
 406
 407	WARN(!dev->absinfo, "%s(): kcalloc() failed?\n", __func__);
 
 
 
 
 
 
 
 
 
 408}
 409EXPORT_SYMBOL(input_alloc_absinfo);
 410
 411void input_set_abs_params(struct input_dev *dev, unsigned int axis,
 412			  int min, int max, int fuzz, int flat)
 413{
 414	struct input_absinfo *absinfo;
 415
 416	input_alloc_absinfo(dev);
 417	if (!dev->absinfo)
 418		return;
 419
 420	absinfo = &dev->absinfo[axis];
 421	absinfo->minimum = min;
 422	absinfo->maximum = max;
 423	absinfo->fuzz = fuzz;
 424	absinfo->flat = flat;
 425
 426	dev->absbit[BIT_WORD(axis)] |= BIT_MASK(axis);
 
 427}
 428EXPORT_SYMBOL(input_set_abs_params);
 429
 430
 431/**
 432 * input_grab_device - grabs device for exclusive use
 433 * @handle: input handle that wants to own the device
 434 *
 435 * When a device is grabbed by an input handle all events generated by
 436 * the device are delivered only to this handle. Also events injected
 437 * by other input handles are ignored while device is grabbed.
 438 */
 439int input_grab_device(struct input_handle *handle)
 440{
 441	struct input_dev *dev = handle->dev;
 442	int retval;
 443
 444	retval = mutex_lock_interruptible(&dev->mutex);
 445	if (retval)
 446		return retval;
 447
 448	if (dev->grab) {
 449		retval = -EBUSY;
 450		goto out;
 451	}
 452
 453	rcu_assign_pointer(dev->grab, handle);
 454
 455 out:
 456	mutex_unlock(&dev->mutex);
 457	return retval;
 458}
 459EXPORT_SYMBOL(input_grab_device);
 460
 461static void __input_release_device(struct input_handle *handle)
 462{
 463	struct input_dev *dev = handle->dev;
 
 464
 465	if (dev->grab == handle) {
 
 
 466		rcu_assign_pointer(dev->grab, NULL);
 467		/* Make sure input_pass_event() notices that grab is gone */
 468		synchronize_rcu();
 469
 470		list_for_each_entry(handle, &dev->h_list, d_node)
 471			if (handle->open && handle->handler->start)
 472				handle->handler->start(handle);
 473	}
 474}
 475
 476/**
 477 * input_release_device - release previously grabbed device
 478 * @handle: input handle that owns the device
 479 *
 480 * Releases previously grabbed device so that other input handles can
 481 * start receiving input events. Upon release all handlers attached
 482 * to the device have their start() method called so they have a change
 483 * to synchronize device state with the rest of the system.
 484 */
 485void input_release_device(struct input_handle *handle)
 486{
 487	struct input_dev *dev = handle->dev;
 488
 489	mutex_lock(&dev->mutex);
 490	__input_release_device(handle);
 491	mutex_unlock(&dev->mutex);
 492}
 493EXPORT_SYMBOL(input_release_device);
 494
 495/**
 496 * input_open_device - open input device
 497 * @handle: handle through which device is being accessed
 498 *
 499 * This function should be called by input handlers when they
 500 * want to start receive events from given input device.
 501 */
 502int input_open_device(struct input_handle *handle)
 503{
 504	struct input_dev *dev = handle->dev;
 505	int retval;
 506
 507	retval = mutex_lock_interruptible(&dev->mutex);
 508	if (retval)
 509		return retval;
 510
 511	if (dev->going_away) {
 512		retval = -ENODEV;
 513		goto out;
 514	}
 515
 516	handle->open++;
 517
 518	if (!dev->users++ && dev->open)
 519		retval = dev->open(dev);
 
 
 
 
 
 520
 521	if (retval) {
 522		dev->users--;
 523		if (!--handle->open) {
 
 
 524			/*
 525			 * Make sure we are not delivering any more events
 526			 * through this handle
 527			 */
 528			synchronize_rcu();
 
 529		}
 530	}
 531
 
 
 
 532 out:
 533	mutex_unlock(&dev->mutex);
 534	return retval;
 535}
 536EXPORT_SYMBOL(input_open_device);
 537
 538int input_flush_device(struct input_handle *handle, struct file *file)
 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->flush)
 548		retval = dev->flush(dev, file);
 549
 550	mutex_unlock(&dev->mutex);
 551	return retval;
 552}
 553EXPORT_SYMBOL(input_flush_device);
 554
 555/**
 556 * input_close_device - close input device
 557 * @handle: handle through which device is being accessed
 558 *
 559 * This function should be called by input handlers when they
 560 * want to stop receive events from given input device.
 561 */
 562void input_close_device(struct input_handle *handle)
 563{
 564	struct input_dev *dev = handle->dev;
 565
 566	mutex_lock(&dev->mutex);
 567
 568	__input_release_device(handle);
 569
 570	if (!--dev->users && dev->close)
 571		dev->close(dev);
 
 
 
 
 
 572
 573	if (!--handle->open) {
 574		/*
 575		 * synchronize_rcu() makes sure that input_pass_event()
 576		 * completed and that no more input events are delivered
 577		 * through this handle
 578		 */
 579		synchronize_rcu();
 580	}
 581
 582	mutex_unlock(&dev->mutex);
 583}
 584EXPORT_SYMBOL(input_close_device);
 585
 586/*
 587 * Simulate keyup events for all keys that are marked as pressed.
 588 * The function must be called with dev->event_lock held.
 589 */
 590static void input_dev_release_keys(struct input_dev *dev)
 591{
 
 592	int code;
 593
 594	if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
 595		for (code = 0; code <= KEY_MAX; code++) {
 596			if (is_event_supported(code, dev->keybit, KEY_MAX) &&
 597			    __test_and_clear_bit(code, dev->key)) {
 598				input_pass_event(dev, EV_KEY, code, 0);
 599			}
 600		}
 601		input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
 
 
 
 
 602	}
 603}
 604
 605/*
 606 * Prepare device for unregistering
 607 */
 608static void input_disconnect_device(struct input_dev *dev)
 609{
 610	struct input_handle *handle;
 611
 612	/*
 613	 * Mark device as going away. Note that we take dev->mutex here
 614	 * not to protect access to dev->going_away but rather to ensure
 615	 * that there are no threads in the middle of input_open_device()
 616	 */
 617	mutex_lock(&dev->mutex);
 618	dev->going_away = true;
 619	mutex_unlock(&dev->mutex);
 620
 621	spin_lock_irq(&dev->event_lock);
 622
 623	/*
 624	 * Simulate keyup events for all pressed keys so that handlers
 625	 * are not left with "stuck" keys. The driver may continue
 626	 * generate events even after we done here but they will not
 627	 * reach any handlers.
 628	 */
 629	input_dev_release_keys(dev);
 630
 631	list_for_each_entry(handle, &dev->h_list, d_node)
 632		handle->open = 0;
 633
 634	spin_unlock_irq(&dev->event_lock);
 635}
 636
 637/**
 638 * input_scancode_to_scalar() - converts scancode in &struct input_keymap_entry
 639 * @ke: keymap entry containing scancode to be converted.
 640 * @scancode: pointer to the location where converted scancode should
 641 *	be stored.
 642 *
 643 * This function is used to convert scancode stored in &struct keymap_entry
 644 * into scalar form understood by legacy keymap handling methods. These
 645 * methods expect scancodes to be represented as 'unsigned int'.
 646 */
 647int input_scancode_to_scalar(const struct input_keymap_entry *ke,
 648			     unsigned int *scancode)
 649{
 650	switch (ke->len) {
 651	case 1:
 652		*scancode = *((u8 *)ke->scancode);
 653		break;
 654
 655	case 2:
 656		*scancode = *((u16 *)ke->scancode);
 657		break;
 658
 659	case 4:
 660		*scancode = *((u32 *)ke->scancode);
 661		break;
 662
 663	default:
 664		return -EINVAL;
 665	}
 666
 667	return 0;
 668}
 669EXPORT_SYMBOL(input_scancode_to_scalar);
 670
 671/*
 672 * Those routines handle the default case where no [gs]etkeycode() is
 673 * defined. In this case, an array indexed by the scancode is used.
 674 */
 675
 676static unsigned int input_fetch_keycode(struct input_dev *dev,
 677					unsigned int index)
 678{
 679	switch (dev->keycodesize) {
 680	case 1:
 681		return ((u8 *)dev->keycode)[index];
 682
 683	case 2:
 684		return ((u16 *)dev->keycode)[index];
 685
 686	default:
 687		return ((u32 *)dev->keycode)[index];
 688	}
 689}
 690
 691static int input_default_getkeycode(struct input_dev *dev,
 692				    struct input_keymap_entry *ke)
 693{
 694	unsigned int index;
 695	int error;
 696
 697	if (!dev->keycodesize)
 698		return -EINVAL;
 699
 700	if (ke->flags & INPUT_KEYMAP_BY_INDEX)
 701		index = ke->index;
 702	else {
 703		error = input_scancode_to_scalar(ke, &index);
 704		if (error)
 705			return error;
 706	}
 707
 708	if (index >= dev->keycodemax)
 709		return -EINVAL;
 710
 711	ke->keycode = input_fetch_keycode(dev, index);
 712	ke->index = index;
 713	ke->len = sizeof(index);
 714	memcpy(ke->scancode, &index, sizeof(index));
 715
 716	return 0;
 717}
 718
 719static int input_default_setkeycode(struct input_dev *dev,
 720				    const struct input_keymap_entry *ke,
 721				    unsigned int *old_keycode)
 722{
 723	unsigned int index;
 724	int error;
 725	int i;
 726
 727	if (!dev->keycodesize)
 728		return -EINVAL;
 729
 730	if (ke->flags & INPUT_KEYMAP_BY_INDEX) {
 731		index = ke->index;
 732	} else {
 733		error = input_scancode_to_scalar(ke, &index);
 734		if (error)
 735			return error;
 736	}
 737
 738	if (index >= dev->keycodemax)
 739		return -EINVAL;
 740
 741	if (dev->keycodesize < sizeof(ke->keycode) &&
 742			(ke->keycode >> (dev->keycodesize * 8)))
 743		return -EINVAL;
 744
 745	switch (dev->keycodesize) {
 746		case 1: {
 747			u8 *k = (u8 *)dev->keycode;
 748			*old_keycode = k[index];
 749			k[index] = ke->keycode;
 750			break;
 751		}
 752		case 2: {
 753			u16 *k = (u16 *)dev->keycode;
 754			*old_keycode = k[index];
 755			k[index] = ke->keycode;
 756			break;
 757		}
 758		default: {
 759			u32 *k = (u32 *)dev->keycode;
 760			*old_keycode = k[index];
 761			k[index] = ke->keycode;
 762			break;
 763		}
 764	}
 765
 766	__clear_bit(*old_keycode, dev->keybit);
 767	__set_bit(ke->keycode, dev->keybit);
 768
 769	for (i = 0; i < dev->keycodemax; i++) {
 770		if (input_fetch_keycode(dev, i) == *old_keycode) {
 771			__set_bit(*old_keycode, dev->keybit);
 772			break; /* Setting the bit twice is useless, so break */
 
 773		}
 774	}
 775
 
 776	return 0;
 777}
 778
 779/**
 780 * input_get_keycode - retrieve keycode currently mapped to a given scancode
 781 * @dev: input device which keymap is being queried
 782 * @ke: keymap entry
 783 *
 784 * This function should be called by anyone interested in retrieving current
 785 * keymap. Presently evdev handlers use it.
 786 */
 787int input_get_keycode(struct input_dev *dev, struct input_keymap_entry *ke)
 788{
 789	unsigned long flags;
 790	int retval;
 791
 792	spin_lock_irqsave(&dev->event_lock, flags);
 793	retval = dev->getkeycode(dev, ke);
 794	spin_unlock_irqrestore(&dev->event_lock, flags);
 795
 796	return retval;
 797}
 798EXPORT_SYMBOL(input_get_keycode);
 799
 800/**
 801 * input_set_keycode - attribute a keycode to a given scancode
 802 * @dev: input device which keymap is being updated
 803 * @ke: new keymap entry
 804 *
 805 * This function should be called by anyone needing to update current
 806 * keymap. Presently keyboard and evdev handlers use it.
 807 */
 808int input_set_keycode(struct input_dev *dev,
 809		      const struct input_keymap_entry *ke)
 810{
 811	unsigned long flags;
 812	unsigned int old_keycode;
 813	int retval;
 814
 815	if (ke->keycode > KEY_MAX)
 816		return -EINVAL;
 817
 818	spin_lock_irqsave(&dev->event_lock, flags);
 819
 820	retval = dev->setkeycode(dev, ke, &old_keycode);
 821	if (retval)
 822		goto out;
 823
 824	/* Make sure KEY_RESERVED did not get enabled. */
 825	__clear_bit(KEY_RESERVED, dev->keybit);
 826
 827	/*
 828	 * Simulate keyup event if keycode is not present
 829	 * in the keymap anymore
 830	 */
 831	if (test_bit(EV_KEY, dev->evbit) &&
 832	    !is_event_supported(old_keycode, dev->keybit, KEY_MAX) &&
 833	    __test_and_clear_bit(old_keycode, dev->key)) {
 
 
 
 
 
 
 
 
 834
 835		input_pass_event(dev, EV_KEY, old_keycode, 0);
 836		if (dev->sync)
 837			input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
 838	}
 839
 840 out:
 841	spin_unlock_irqrestore(&dev->event_lock, flags);
 842
 843	return retval;
 844}
 845EXPORT_SYMBOL(input_set_keycode);
 846
 847#define MATCH_BIT(bit, max) \
 848		for (i = 0; i < BITS_TO_LONGS(max); i++) \
 849			if ((id->bit[i] & dev->bit[i]) != id->bit[i]) \
 850				break; \
 851		if (i != BITS_TO_LONGS(max)) \
 852			continue;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 853
 854static const struct input_device_id *input_match_device(struct input_handler *handler,
 855							struct input_dev *dev)
 856{
 857	const struct input_device_id *id;
 858	int i;
 859
 860	for (id = handler->id_table; id->flags || id->driver_info; id++) {
 861
 862		if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
 863			if (id->bustype != dev->id.bustype)
 864				continue;
 865
 866		if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
 867			if (id->vendor != dev->id.vendor)
 868				continue;
 869
 870		if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
 871			if (id->product != dev->id.product)
 872				continue;
 873
 874		if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
 875			if (id->version != dev->id.version)
 876				continue;
 877
 878		MATCH_BIT(evbit,  EV_MAX);
 879		MATCH_BIT(keybit, KEY_MAX);
 880		MATCH_BIT(relbit, REL_MAX);
 881		MATCH_BIT(absbit, ABS_MAX);
 882		MATCH_BIT(mscbit, MSC_MAX);
 883		MATCH_BIT(ledbit, LED_MAX);
 884		MATCH_BIT(sndbit, SND_MAX);
 885		MATCH_BIT(ffbit,  FF_MAX);
 886		MATCH_BIT(swbit,  SW_MAX);
 887
 888		if (!handler->match || handler->match(handler, dev))
 889			return id;
 
 890	}
 891
 892	return NULL;
 893}
 894
 895static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
 896{
 897	const struct input_device_id *id;
 898	int error;
 899
 900	id = input_match_device(handler, dev);
 901	if (!id)
 902		return -ENODEV;
 903
 904	error = handler->connect(handler, dev, id);
 905	if (error && error != -ENODEV)
 906		pr_err("failed to attach handler %s to device %s, error: %d\n",
 907		       handler->name, kobject_name(&dev->dev.kobj), error);
 908
 909	return error;
 910}
 911
 912#ifdef CONFIG_COMPAT
 913
 914static int input_bits_to_string(char *buf, int buf_size,
 915				unsigned long bits, bool skip_empty)
 916{
 917	int len = 0;
 918
 919	if (INPUT_COMPAT_TEST) {
 920		u32 dword = bits >> 32;
 921		if (dword || !skip_empty)
 922			len += snprintf(buf, buf_size, "%x ", dword);
 923
 924		dword = bits & 0xffffffffUL;
 925		if (dword || !skip_empty || len)
 926			len += snprintf(buf + len, max(buf_size - len, 0),
 927					"%x", dword);
 928	} else {
 929		if (bits || !skip_empty)
 930			len += snprintf(buf, buf_size, "%lx", bits);
 931	}
 932
 933	return len;
 934}
 935
 936#else /* !CONFIG_COMPAT */
 937
 938static int input_bits_to_string(char *buf, int buf_size,
 939				unsigned long bits, bool skip_empty)
 940{
 941	return bits || !skip_empty ?
 942		snprintf(buf, buf_size, "%lx", bits) : 0;
 943}
 944
 945#endif
 946
 947#ifdef CONFIG_PROC_FS
 948
 949static struct proc_dir_entry *proc_bus_input_dir;
 950static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
 951static int input_devices_state;
 952
 953static inline void input_wakeup_procfs_readers(void)
 954{
 955	input_devices_state++;
 956	wake_up(&input_devices_poll_wait);
 957}
 958
 959static unsigned int input_proc_devices_poll(struct file *file, poll_table *wait)
 960{
 961	poll_wait(file, &input_devices_poll_wait, wait);
 962	if (file->f_version != input_devices_state) {
 963		file->f_version = input_devices_state;
 964		return POLLIN | POLLRDNORM;
 965	}
 966
 967	return 0;
 968}
 969
 970union input_seq_state {
 971	struct {
 972		unsigned short pos;
 973		bool mutex_acquired;
 974	};
 975	void *p;
 976};
 977
 978static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
 979{
 980	union input_seq_state *state = (union input_seq_state *)&seq->private;
 981	int error;
 982
 983	/* We need to fit into seq->private pointer */
 984	BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
 985
 986	error = mutex_lock_interruptible(&input_mutex);
 987	if (error) {
 988		state->mutex_acquired = false;
 989		return ERR_PTR(error);
 990	}
 991
 992	state->mutex_acquired = true;
 993
 994	return seq_list_start(&input_dev_list, *pos);
 995}
 996
 997static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 998{
 999	return seq_list_next(v, &input_dev_list, pos);
1000}
1001
1002static void input_seq_stop(struct seq_file *seq, void *v)
1003{
1004	union input_seq_state *state = (union input_seq_state *)&seq->private;
1005
1006	if (state->mutex_acquired)
1007		mutex_unlock(&input_mutex);
1008}
1009
1010static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
1011				   unsigned long *bitmap, int max)
1012{
1013	int i;
1014	bool skip_empty = true;
1015	char buf[18];
1016
1017	seq_printf(seq, "B: %s=", name);
1018
1019	for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1020		if (input_bits_to_string(buf, sizeof(buf),
1021					 bitmap[i], skip_empty)) {
1022			skip_empty = false;
1023			seq_printf(seq, "%s%s", buf, i > 0 ? " " : "");
1024		}
1025	}
1026
1027	/*
1028	 * If no output was produced print a single 0.
1029	 */
1030	if (skip_empty)
1031		seq_puts(seq, "0");
1032
1033	seq_putc(seq, '\n');
1034}
1035
1036static int input_devices_seq_show(struct seq_file *seq, void *v)
1037{
1038	struct input_dev *dev = container_of(v, struct input_dev, node);
1039	const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1040	struct input_handle *handle;
1041
1042	seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
1043		   dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
1044
1045	seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
1046	seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
1047	seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
1048	seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
1049	seq_printf(seq, "H: Handlers=");
1050
1051	list_for_each_entry(handle, &dev->h_list, d_node)
1052		seq_printf(seq, "%s ", handle->name);
1053	seq_putc(seq, '\n');
1054
1055	input_seq_print_bitmap(seq, "PROP", dev->propbit, INPUT_PROP_MAX);
1056
1057	input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
1058	if (test_bit(EV_KEY, dev->evbit))
1059		input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
1060	if (test_bit(EV_REL, dev->evbit))
1061		input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
1062	if (test_bit(EV_ABS, dev->evbit))
1063		input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
1064	if (test_bit(EV_MSC, dev->evbit))
1065		input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
1066	if (test_bit(EV_LED, dev->evbit))
1067		input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
1068	if (test_bit(EV_SND, dev->evbit))
1069		input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
1070	if (test_bit(EV_FF, dev->evbit))
1071		input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
1072	if (test_bit(EV_SW, dev->evbit))
1073		input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);
1074
1075	seq_putc(seq, '\n');
1076
1077	kfree(path);
1078	return 0;
1079}
1080
1081static const struct seq_operations input_devices_seq_ops = {
1082	.start	= input_devices_seq_start,
1083	.next	= input_devices_seq_next,
1084	.stop	= input_seq_stop,
1085	.show	= input_devices_seq_show,
1086};
1087
1088static int input_proc_devices_open(struct inode *inode, struct file *file)
1089{
1090	return seq_open(file, &input_devices_seq_ops);
1091}
1092
1093static const struct file_operations input_devices_fileops = {
1094	.owner		= THIS_MODULE,
1095	.open		= input_proc_devices_open,
1096	.poll		= input_proc_devices_poll,
1097	.read		= seq_read,
1098	.llseek		= seq_lseek,
1099	.release	= seq_release,
1100};
1101
1102static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
1103{
1104	union input_seq_state *state = (union input_seq_state *)&seq->private;
1105	int error;
1106
1107	/* We need to fit into seq->private pointer */
1108	BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1109
1110	error = mutex_lock_interruptible(&input_mutex);
1111	if (error) {
1112		state->mutex_acquired = false;
1113		return ERR_PTR(error);
1114	}
1115
1116	state->mutex_acquired = true;
1117	state->pos = *pos;
1118
1119	return seq_list_start(&input_handler_list, *pos);
1120}
1121
1122static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1123{
1124	union input_seq_state *state = (union input_seq_state *)&seq->private;
1125
1126	state->pos = *pos + 1;
1127	return seq_list_next(v, &input_handler_list, pos);
1128}
1129
1130static int input_handlers_seq_show(struct seq_file *seq, void *v)
1131{
1132	struct input_handler *handler = container_of(v, struct input_handler, node);
1133	union input_seq_state *state = (union input_seq_state *)&seq->private;
1134
1135	seq_printf(seq, "N: Number=%u Name=%s", state->pos, handler->name);
1136	if (handler->filter)
1137		seq_puts(seq, " (filter)");
1138	if (handler->fops)
1139		seq_printf(seq, " Minor=%d", handler->minor);
1140	seq_putc(seq, '\n');
1141
1142	return 0;
1143}
1144
1145static const struct seq_operations input_handlers_seq_ops = {
1146	.start	= input_handlers_seq_start,
1147	.next	= input_handlers_seq_next,
1148	.stop	= input_seq_stop,
1149	.show	= input_handlers_seq_show,
1150};
1151
1152static int input_proc_handlers_open(struct inode *inode, struct file *file)
1153{
1154	return seq_open(file, &input_handlers_seq_ops);
1155}
1156
1157static const struct file_operations input_handlers_fileops = {
1158	.owner		= THIS_MODULE,
1159	.open		= input_proc_handlers_open,
1160	.read		= seq_read,
1161	.llseek		= seq_lseek,
1162	.release	= seq_release,
1163};
1164
1165static int __init input_proc_init(void)
1166{
1167	struct proc_dir_entry *entry;
1168
1169	proc_bus_input_dir = proc_mkdir("bus/input", NULL);
1170	if (!proc_bus_input_dir)
1171		return -ENOMEM;
1172
1173	entry = proc_create("devices", 0, proc_bus_input_dir,
1174			    &input_devices_fileops);
1175	if (!entry)
1176		goto fail1;
1177
1178	entry = proc_create("handlers", 0, proc_bus_input_dir,
1179			    &input_handlers_fileops);
1180	if (!entry)
1181		goto fail2;
1182
1183	return 0;
1184
1185 fail2:	remove_proc_entry("devices", proc_bus_input_dir);
1186 fail1: remove_proc_entry("bus/input", NULL);
1187	return -ENOMEM;
1188}
1189
1190static void input_proc_exit(void)
1191{
1192	remove_proc_entry("devices", proc_bus_input_dir);
1193	remove_proc_entry("handlers", proc_bus_input_dir);
1194	remove_proc_entry("bus/input", NULL);
1195}
1196
1197#else /* !CONFIG_PROC_FS */
1198static inline void input_wakeup_procfs_readers(void) { }
1199static inline int input_proc_init(void) { return 0; }
1200static inline void input_proc_exit(void) { }
1201#endif
1202
1203#define INPUT_DEV_STRING_ATTR_SHOW(name)				\
1204static ssize_t input_dev_show_##name(struct device *dev,		\
1205				     struct device_attribute *attr,	\
1206				     char *buf)				\
1207{									\
1208	struct input_dev *input_dev = to_input_dev(dev);		\
1209									\
1210	return scnprintf(buf, PAGE_SIZE, "%s\n",			\
1211			 input_dev->name ? input_dev->name : "");	\
1212}									\
1213static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
1214
1215INPUT_DEV_STRING_ATTR_SHOW(name);
1216INPUT_DEV_STRING_ATTR_SHOW(phys);
1217INPUT_DEV_STRING_ATTR_SHOW(uniq);
1218
1219static int input_print_modalias_bits(char *buf, int size,
1220				     char name, unsigned long *bm,
1221				     unsigned int min_bit, unsigned int max_bit)
1222{
1223	int len = 0, i;
1224
1225	len += snprintf(buf, max(size, 0), "%c", name);
1226	for (i = min_bit; i < max_bit; i++)
1227		if (bm[BIT_WORD(i)] & BIT_MASK(i))
1228			len += snprintf(buf + len, max(size - len, 0), "%X,", i);
1229	return len;
1230}
1231
1232static int input_print_modalias(char *buf, int size, struct input_dev *id,
1233				int add_cr)
1234{
1235	int len;
1236
1237	len = snprintf(buf, max(size, 0),
1238		       "input:b%04Xv%04Xp%04Xe%04X-",
1239		       id->id.bustype, id->id.vendor,
1240		       id->id.product, id->id.version);
1241
1242	len += input_print_modalias_bits(buf + len, size - len,
1243				'e', id->evbit, 0, EV_MAX);
1244	len += input_print_modalias_bits(buf + len, size - len,
1245				'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
1246	len += input_print_modalias_bits(buf + len, size - len,
1247				'r', id->relbit, 0, REL_MAX);
1248	len += input_print_modalias_bits(buf + len, size - len,
1249				'a', id->absbit, 0, ABS_MAX);
1250	len += input_print_modalias_bits(buf + len, size - len,
1251				'm', id->mscbit, 0, MSC_MAX);
1252	len += input_print_modalias_bits(buf + len, size - len,
1253				'l', id->ledbit, 0, LED_MAX);
1254	len += input_print_modalias_bits(buf + len, size - len,
1255				's', id->sndbit, 0, SND_MAX);
1256	len += input_print_modalias_bits(buf + len, size - len,
1257				'f', id->ffbit, 0, FF_MAX);
1258	len += input_print_modalias_bits(buf + len, size - len,
1259				'w', id->swbit, 0, SW_MAX);
1260
1261	if (add_cr)
1262		len += snprintf(buf + len, max(size - len, 0), "\n");
1263
1264	return len;
1265}
1266
1267static ssize_t input_dev_show_modalias(struct device *dev,
1268				       struct device_attribute *attr,
1269				       char *buf)
1270{
1271	struct input_dev *id = to_input_dev(dev);
1272	ssize_t len;
1273
1274	len = input_print_modalias(buf, PAGE_SIZE, id, 1);
1275
1276	return min_t(int, len, PAGE_SIZE);
1277}
1278static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
1279
1280static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1281			      int max, int add_cr);
1282
1283static ssize_t input_dev_show_properties(struct device *dev,
1284					 struct device_attribute *attr,
1285					 char *buf)
1286{
1287	struct input_dev *input_dev = to_input_dev(dev);
1288	int len = input_print_bitmap(buf, PAGE_SIZE, input_dev->propbit,
1289				     INPUT_PROP_MAX, true);
1290	return min_t(int, len, PAGE_SIZE);
1291}
1292static DEVICE_ATTR(properties, S_IRUGO, input_dev_show_properties, NULL);
1293
1294static struct attribute *input_dev_attrs[] = {
1295	&dev_attr_name.attr,
1296	&dev_attr_phys.attr,
1297	&dev_attr_uniq.attr,
1298	&dev_attr_modalias.attr,
1299	&dev_attr_properties.attr,
1300	NULL
1301};
1302
1303static struct attribute_group input_dev_attr_group = {
1304	.attrs	= input_dev_attrs,
1305};
1306
1307#define INPUT_DEV_ID_ATTR(name)						\
1308static ssize_t input_dev_show_id_##name(struct device *dev,		\
1309					struct device_attribute *attr,	\
1310					char *buf)			\
1311{									\
1312	struct input_dev *input_dev = to_input_dev(dev);		\
1313	return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name);	\
1314}									\
1315static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
1316
1317INPUT_DEV_ID_ATTR(bustype);
1318INPUT_DEV_ID_ATTR(vendor);
1319INPUT_DEV_ID_ATTR(product);
1320INPUT_DEV_ID_ATTR(version);
1321
1322static struct attribute *input_dev_id_attrs[] = {
1323	&dev_attr_bustype.attr,
1324	&dev_attr_vendor.attr,
1325	&dev_attr_product.attr,
1326	&dev_attr_version.attr,
1327	NULL
1328};
1329
1330static struct attribute_group input_dev_id_attr_group = {
1331	.name	= "id",
1332	.attrs	= input_dev_id_attrs,
1333};
1334
1335static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1336			      int max, int add_cr)
1337{
1338	int i;
1339	int len = 0;
1340	bool skip_empty = true;
1341
1342	for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1343		len += input_bits_to_string(buf + len, max(buf_size - len, 0),
1344					    bitmap[i], skip_empty);
1345		if (len) {
1346			skip_empty = false;
1347			if (i > 0)
1348				len += snprintf(buf + len, max(buf_size - len, 0), " ");
1349		}
1350	}
1351
1352	/*
1353	 * If no output was produced print a single 0.
1354	 */
1355	if (len == 0)
1356		len = snprintf(buf, buf_size, "%d", 0);
1357
1358	if (add_cr)
1359		len += snprintf(buf + len, max(buf_size - len, 0), "\n");
1360
1361	return len;
1362}
1363
1364#define INPUT_DEV_CAP_ATTR(ev, bm)					\
1365static ssize_t input_dev_show_cap_##bm(struct device *dev,		\
1366				       struct device_attribute *attr,	\
1367				       char *buf)			\
1368{									\
1369	struct input_dev *input_dev = to_input_dev(dev);		\
1370	int len = input_print_bitmap(buf, PAGE_SIZE,			\
1371				     input_dev->bm##bit, ev##_MAX,	\
1372				     true);				\
1373	return min_t(int, len, PAGE_SIZE);				\
1374}									\
1375static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
1376
1377INPUT_DEV_CAP_ATTR(EV, ev);
1378INPUT_DEV_CAP_ATTR(KEY, key);
1379INPUT_DEV_CAP_ATTR(REL, rel);
1380INPUT_DEV_CAP_ATTR(ABS, abs);
1381INPUT_DEV_CAP_ATTR(MSC, msc);
1382INPUT_DEV_CAP_ATTR(LED, led);
1383INPUT_DEV_CAP_ATTR(SND, snd);
1384INPUT_DEV_CAP_ATTR(FF, ff);
1385INPUT_DEV_CAP_ATTR(SW, sw);
1386
1387static struct attribute *input_dev_caps_attrs[] = {
1388	&dev_attr_ev.attr,
1389	&dev_attr_key.attr,
1390	&dev_attr_rel.attr,
1391	&dev_attr_abs.attr,
1392	&dev_attr_msc.attr,
1393	&dev_attr_led.attr,
1394	&dev_attr_snd.attr,
1395	&dev_attr_ff.attr,
1396	&dev_attr_sw.attr,
1397	NULL
1398};
1399
1400static struct attribute_group input_dev_caps_attr_group = {
1401	.name	= "capabilities",
1402	.attrs	= input_dev_caps_attrs,
1403};
1404
1405static const struct attribute_group *input_dev_attr_groups[] = {
1406	&input_dev_attr_group,
1407	&input_dev_id_attr_group,
1408	&input_dev_caps_attr_group,
 
1409	NULL
1410};
1411
1412static void input_dev_release(struct device *device)
1413{
1414	struct input_dev *dev = to_input_dev(device);
1415
1416	input_ff_destroy(dev);
1417	input_mt_destroy_slots(dev);
 
1418	kfree(dev->absinfo);
 
1419	kfree(dev);
1420
1421	module_put(THIS_MODULE);
1422}
1423
1424/*
1425 * Input uevent interface - loading event handlers based on
1426 * device bitfields.
1427 */
1428static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
1429				   const char *name, unsigned long *bitmap, int max)
1430{
1431	int len;
1432
1433	if (add_uevent_var(env, "%s", name))
1434		return -ENOMEM;
1435
1436	len = input_print_bitmap(&env->buf[env->buflen - 1],
1437				 sizeof(env->buf) - env->buflen,
1438				 bitmap, max, false);
1439	if (len >= (sizeof(env->buf) - env->buflen))
1440		return -ENOMEM;
1441
1442	env->buflen += len;
1443	return 0;
1444}
1445
1446static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
1447					 struct input_dev *dev)
1448{
1449	int len;
1450
1451	if (add_uevent_var(env, "MODALIAS="))
1452		return -ENOMEM;
1453
1454	len = input_print_modalias(&env->buf[env->buflen - 1],
1455				   sizeof(env->buf) - env->buflen,
1456				   dev, 0);
1457	if (len >= (sizeof(env->buf) - env->buflen))
1458		return -ENOMEM;
1459
1460	env->buflen += len;
1461	return 0;
1462}
1463
1464#define INPUT_ADD_HOTPLUG_VAR(fmt, val...)				\
1465	do {								\
1466		int err = add_uevent_var(env, fmt, val);		\
1467		if (err)						\
1468			return err;					\
1469	} while (0)
1470
1471#define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max)				\
1472	do {								\
1473		int err = input_add_uevent_bm_var(env, name, bm, max);	\
1474		if (err)						\
1475			return err;					\
1476	} while (0)
1477
1478#define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev)				\
1479	do {								\
1480		int err = input_add_uevent_modalias_var(env, dev);	\
1481		if (err)						\
1482			return err;					\
1483	} while (0)
1484
1485static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
1486{
1487	struct input_dev *dev = to_input_dev(device);
1488
1489	INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
1490				dev->id.bustype, dev->id.vendor,
1491				dev->id.product, dev->id.version);
1492	if (dev->name)
1493		INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
1494	if (dev->phys)
1495		INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
1496	if (dev->uniq)
1497		INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
1498
1499	INPUT_ADD_HOTPLUG_BM_VAR("PROP=", dev->propbit, INPUT_PROP_MAX);
1500
1501	INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
1502	if (test_bit(EV_KEY, dev->evbit))
1503		INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
1504	if (test_bit(EV_REL, dev->evbit))
1505		INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
1506	if (test_bit(EV_ABS, dev->evbit))
1507		INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
1508	if (test_bit(EV_MSC, dev->evbit))
1509		INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
1510	if (test_bit(EV_LED, dev->evbit))
1511		INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
1512	if (test_bit(EV_SND, dev->evbit))
1513		INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
1514	if (test_bit(EV_FF, dev->evbit))
1515		INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
1516	if (test_bit(EV_SW, dev->evbit))
1517		INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
1518
1519	INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
1520
1521	return 0;
1522}
1523
1524#define INPUT_DO_TOGGLE(dev, type, bits, on)				\
1525	do {								\
1526		int i;							\
1527		bool active;						\
1528									\
1529		if (!test_bit(EV_##type, dev->evbit))			\
1530			break;						\
1531									\
1532		for (i = 0; i < type##_MAX; i++) {			\
1533			if (!test_bit(i, dev->bits##bit))		\
1534				continue;				\
1535									\
1536			active = test_bit(i, dev->bits);		\
1537			if (!active && !on)				\
1538				continue;				\
1539									\
1540			dev->event(dev, EV_##type, i, on ? active : 0);	\
1541		}							\
1542	} while (0)
1543
1544static void input_dev_toggle(struct input_dev *dev, bool activate)
1545{
1546	if (!dev->event)
1547		return;
1548
1549	INPUT_DO_TOGGLE(dev, LED, led, activate);
1550	INPUT_DO_TOGGLE(dev, SND, snd, activate);
1551
1552	if (activate && test_bit(EV_REP, dev->evbit)) {
1553		dev->event(dev, EV_REP, REP_PERIOD, dev->rep[REP_PERIOD]);
1554		dev->event(dev, EV_REP, REP_DELAY, dev->rep[REP_DELAY]);
1555	}
1556}
1557
1558/**
1559 * input_reset_device() - reset/restore the state of input device
1560 * @dev: input device whose state needs to be reset
1561 *
1562 * This function tries to reset the state of an opened input device and
1563 * bring internal state and state if the hardware in sync with each other.
1564 * We mark all keys as released, restore LED state, repeat rate, etc.
1565 */
1566void input_reset_device(struct input_dev *dev)
1567{
1568	mutex_lock(&dev->mutex);
1569
1570	if (dev->users) {
1571		input_dev_toggle(dev, true);
1572
1573		/*
1574		 * Keys that have been pressed at suspend time are unlikely
1575		 * to be still pressed when we resume.
1576		 */
1577		spin_lock_irq(&dev->event_lock);
1578		input_dev_release_keys(dev);
1579		spin_unlock_irq(&dev->event_lock);
1580	}
1581
 
1582	mutex_unlock(&dev->mutex);
1583}
1584EXPORT_SYMBOL(input_reset_device);
1585
1586#ifdef CONFIG_PM
1587static int input_dev_suspend(struct device *dev)
1588{
1589	struct input_dev *input_dev = to_input_dev(dev);
1590
1591	mutex_lock(&input_dev->mutex);
1592
1593	if (input_dev->users)
1594		input_dev_toggle(input_dev, false);
 
 
 
 
 
 
1595
1596	mutex_unlock(&input_dev->mutex);
1597
1598	return 0;
1599}
1600
1601static int input_dev_resume(struct device *dev)
1602{
1603	struct input_dev *input_dev = to_input_dev(dev);
1604
1605	input_reset_device(input_dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1606
1607	return 0;
1608}
1609
1610static const struct dev_pm_ops input_dev_pm_ops = {
1611	.suspend	= input_dev_suspend,
1612	.resume		= input_dev_resume,
1613	.poweroff	= input_dev_suspend,
 
1614	.restore	= input_dev_resume,
1615};
1616#endif /* CONFIG_PM */
1617
1618static struct device_type input_dev_type = {
1619	.groups		= input_dev_attr_groups,
1620	.release	= input_dev_release,
1621	.uevent		= input_dev_uevent,
1622#ifdef CONFIG_PM
1623	.pm		= &input_dev_pm_ops,
1624#endif
1625};
1626
1627static char *input_devnode(struct device *dev, mode_t *mode)
1628{
1629	return kasprintf(GFP_KERNEL, "input/%s", dev_name(dev));
1630}
1631
1632struct class input_class = {
1633	.name		= "input",
1634	.devnode	= input_devnode,
1635};
1636EXPORT_SYMBOL_GPL(input_class);
1637
1638/**
1639 * input_allocate_device - allocate memory for new input device
1640 *
1641 * Returns prepared struct input_dev or NULL.
1642 *
1643 * NOTE: Use input_free_device() to free devices that have not been
1644 * registered; input_unregister_device() should be used for already
1645 * registered devices.
1646 */
1647struct input_dev *input_allocate_device(void)
1648{
 
1649	struct input_dev *dev;
1650
1651	dev = kzalloc(sizeof(struct input_dev), GFP_KERNEL);
1652	if (dev) {
1653		dev->dev.type = &input_dev_type;
1654		dev->dev.class = &input_class;
1655		device_initialize(&dev->dev);
1656		mutex_init(&dev->mutex);
1657		spin_lock_init(&dev->event_lock);
 
1658		INIT_LIST_HEAD(&dev->h_list);
1659		INIT_LIST_HEAD(&dev->node);
1660
 
 
 
1661		__module_get(THIS_MODULE);
1662	}
1663
1664	return dev;
1665}
1666EXPORT_SYMBOL(input_allocate_device);
1667
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1668/**
1669 * input_free_device - free memory occupied by input_dev structure
1670 * @dev: input device to free
1671 *
1672 * This function should only be used if input_register_device()
1673 * was not called yet or if it failed. Once device was registered
1674 * use input_unregister_device() and memory will be freed once last
1675 * reference to the device is dropped.
1676 *
1677 * Device should be allocated by input_allocate_device().
1678 *
1679 * NOTE: If there are references to the input device then memory
1680 * will not be freed until last reference is dropped.
1681 */
1682void input_free_device(struct input_dev *dev)
1683{
1684	if (dev)
 
 
 
 
 
1685		input_put_device(dev);
 
1686}
1687EXPORT_SYMBOL(input_free_device);
1688
1689/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1690 * input_set_capability - mark device as capable of a certain event
1691 * @dev: device that is capable of emitting or accepting event
1692 * @type: type of the event (EV_KEY, EV_REL, etc...)
1693 * @code: event code
1694 *
1695 * In addition to setting up corresponding bit in appropriate capability
1696 * bitmap the function also adjusts dev->evbit.
1697 */
1698void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
1699{
1700	switch (type) {
1701	case EV_KEY:
1702		__set_bit(code, dev->keybit);
1703		break;
1704
1705	case EV_REL:
1706		__set_bit(code, dev->relbit);
1707		break;
1708
1709	case EV_ABS:
 
 
 
 
1710		__set_bit(code, dev->absbit);
1711		break;
1712
1713	case EV_MSC:
1714		__set_bit(code, dev->mscbit);
1715		break;
1716
1717	case EV_SW:
1718		__set_bit(code, dev->swbit);
1719		break;
1720
1721	case EV_LED:
1722		__set_bit(code, dev->ledbit);
1723		break;
1724
1725	case EV_SND:
1726		__set_bit(code, dev->sndbit);
1727		break;
1728
1729	case EV_FF:
1730		__set_bit(code, dev->ffbit);
1731		break;
1732
1733	case EV_PWR:
1734		/* do nothing */
1735		break;
1736
1737	default:
1738		pr_err("input_set_capability: unknown type %u (code %u)\n",
1739		       type, code);
1740		dump_stack();
1741		return;
1742	}
1743
1744	__set_bit(type, dev->evbit);
1745}
1746EXPORT_SYMBOL(input_set_capability);
1747
1748static unsigned int input_estimate_events_per_packet(struct input_dev *dev)
1749{
1750	int mt_slots;
1751	int i;
1752	unsigned int events;
1753
1754	if (dev->mtsize) {
1755		mt_slots = dev->mtsize;
1756	} else if (test_bit(ABS_MT_TRACKING_ID, dev->absbit)) {
1757		mt_slots = dev->absinfo[ABS_MT_TRACKING_ID].maximum -
1758			   dev->absinfo[ABS_MT_TRACKING_ID].minimum + 1,
1759		mt_slots = clamp(mt_slots, 2, 32);
1760	} else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
1761		mt_slots = 2;
1762	} else {
1763		mt_slots = 0;
1764	}
1765
1766	events = mt_slots + 1; /* count SYN_MT_REPORT and SYN_REPORT */
1767
1768	for (i = 0; i < ABS_CNT; i++) {
1769		if (test_bit(i, dev->absbit)) {
1770			if (input_is_mt_axis(i))
1771				events += mt_slots;
1772			else
1773				events++;
1774		}
1775	}
1776
1777	for (i = 0; i < REL_CNT; i++)
1778		if (test_bit(i, dev->relbit))
1779			events++;
 
 
1780
1781	return events;
1782}
1783
1784#define INPUT_CLEANSE_BITMASK(dev, type, bits)				\
1785	do {								\
1786		if (!test_bit(EV_##type, dev->evbit))			\
1787			memset(dev->bits##bit, 0,			\
1788				sizeof(dev->bits##bit));		\
1789	} while (0)
1790
1791static void input_cleanse_bitmasks(struct input_dev *dev)
1792{
1793	INPUT_CLEANSE_BITMASK(dev, KEY, key);
1794	INPUT_CLEANSE_BITMASK(dev, REL, rel);
1795	INPUT_CLEANSE_BITMASK(dev, ABS, abs);
1796	INPUT_CLEANSE_BITMASK(dev, MSC, msc);
1797	INPUT_CLEANSE_BITMASK(dev, LED, led);
1798	INPUT_CLEANSE_BITMASK(dev, SND, snd);
1799	INPUT_CLEANSE_BITMASK(dev, FF, ff);
1800	INPUT_CLEANSE_BITMASK(dev, SW, sw);
1801}
1802
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1803/**
1804 * input_register_device - register device with input core
1805 * @dev: device to be registered
1806 *
1807 * This function registers device with input core. The device must be
1808 * allocated with input_allocate_device() and all it's capabilities
1809 * set up before registering.
1810 * If function fails the device must be freed with input_free_device().
1811 * Once device has been successfully registered it can be unregistered
1812 * with input_unregister_device(); input_free_device() should not be
1813 * called in this case.
 
 
 
 
 
 
 
 
 
 
 
1814 */
1815int input_register_device(struct input_dev *dev)
1816{
1817	static atomic_t input_no = ATOMIC_INIT(0);
1818	struct input_handler *handler;
 
1819	const char *path;
1820	int error;
1821
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1822	/* Every input device generates EV_SYN/SYN_REPORT events. */
1823	__set_bit(EV_SYN, dev->evbit);
1824
1825	/* KEY_RESERVED is not supposed to be transmitted to userspace. */
1826	__clear_bit(KEY_RESERVED, dev->keybit);
1827
1828	/* Make sure that bitmasks not mentioned in dev->evbit are clean. */
1829	input_cleanse_bitmasks(dev);
1830
1831	if (!dev->hint_events_per_packet)
1832		dev->hint_events_per_packet =
1833				input_estimate_events_per_packet(dev);
 
 
 
 
 
 
 
1834
1835	/*
1836	 * If delay and period are pre-set by the driver, then autorepeating
1837	 * is handled by the driver itself and we don't do it in input.c.
1838	 */
1839	init_timer(&dev->timer);
1840	if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD]) {
1841		dev->timer.data = (long) dev;
1842		dev->timer.function = input_repeat_key;
1843		dev->rep[REP_DELAY] = 250;
1844		dev->rep[REP_PERIOD] = 33;
1845	}
1846
1847	if (!dev->getkeycode)
1848		dev->getkeycode = input_default_getkeycode;
1849
1850	if (!dev->setkeycode)
1851		dev->setkeycode = input_default_setkeycode;
1852
1853	dev_set_name(&dev->dev, "input%ld",
1854		     (unsigned long) atomic_inc_return(&input_no) - 1);
1855
1856	error = device_add(&dev->dev);
1857	if (error)
1858		return error;
1859
1860	path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1861	pr_info("%s as %s\n",
1862		dev->name ? dev->name : "Unspecified device",
1863		path ? path : "N/A");
1864	kfree(path);
1865
1866	error = mutex_lock_interruptible(&input_mutex);
1867	if (error) {
1868		device_del(&dev->dev);
1869		return error;
1870	}
1871
1872	list_add_tail(&dev->node, &input_dev_list);
1873
1874	list_for_each_entry(handler, &input_handler_list, node)
1875		input_attach_handler(dev, handler);
1876
1877	input_wakeup_procfs_readers();
1878
1879	mutex_unlock(&input_mutex);
1880
 
 
 
 
 
1881	return 0;
 
 
 
 
 
 
 
 
 
1882}
1883EXPORT_SYMBOL(input_register_device);
1884
1885/**
1886 * input_unregister_device - unregister previously registered device
1887 * @dev: device to be unregistered
1888 *
1889 * This function unregisters an input device. Once device is unregistered
1890 * the caller should not try to access it as it may get freed at any moment.
1891 */
1892void input_unregister_device(struct input_dev *dev)
1893{
1894	struct input_handle *handle, *next;
1895
1896	input_disconnect_device(dev);
1897
1898	mutex_lock(&input_mutex);
1899
1900	list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
1901		handle->handler->disconnect(handle);
1902	WARN_ON(!list_empty(&dev->h_list));
1903
1904	del_timer_sync(&dev->timer);
1905	list_del_init(&dev->node);
1906
1907	input_wakeup_procfs_readers();
1908
1909	mutex_unlock(&input_mutex);
1910
1911	device_unregister(&dev->dev);
1912}
1913EXPORT_SYMBOL(input_unregister_device);
1914
1915/**
1916 * input_register_handler - register a new input handler
1917 * @handler: handler to be registered
1918 *
1919 * This function registers a new input handler (interface) for input
1920 * devices in the system and attaches it to all input devices that
1921 * are compatible with the handler.
1922 */
1923int input_register_handler(struct input_handler *handler)
1924{
1925	struct input_dev *dev;
1926	int retval;
1927
1928	retval = mutex_lock_interruptible(&input_mutex);
1929	if (retval)
1930		return retval;
1931
1932	INIT_LIST_HEAD(&handler->h_list);
1933
1934	if (handler->fops != NULL) {
1935		if (input_table[handler->minor >> 5]) {
1936			retval = -EBUSY;
1937			goto out;
1938		}
1939		input_table[handler->minor >> 5] = handler;
1940	}
1941
1942	list_add_tail(&handler->node, &input_handler_list);
1943
1944	list_for_each_entry(dev, &input_dev_list, node)
1945		input_attach_handler(dev, handler);
1946
1947	input_wakeup_procfs_readers();
1948
1949 out:
1950	mutex_unlock(&input_mutex);
1951	return retval;
1952}
1953EXPORT_SYMBOL(input_register_handler);
1954
1955/**
1956 * input_unregister_handler - unregisters an input handler
1957 * @handler: handler to be unregistered
1958 *
1959 * This function disconnects a handler from its input devices and
1960 * removes it from lists of known handlers.
1961 */
1962void input_unregister_handler(struct input_handler *handler)
1963{
1964	struct input_handle *handle, *next;
1965
1966	mutex_lock(&input_mutex);
1967
1968	list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
1969		handler->disconnect(handle);
1970	WARN_ON(!list_empty(&handler->h_list));
1971
1972	list_del_init(&handler->node);
1973
1974	if (handler->fops != NULL)
1975		input_table[handler->minor >> 5] = NULL;
1976
1977	input_wakeup_procfs_readers();
1978
1979	mutex_unlock(&input_mutex);
1980}
1981EXPORT_SYMBOL(input_unregister_handler);
1982
1983/**
1984 * input_handler_for_each_handle - handle iterator
1985 * @handler: input handler to iterate
1986 * @data: data for the callback
1987 * @fn: function to be called for each handle
1988 *
1989 * Iterate over @bus's list of devices, and call @fn for each, passing
1990 * it @data and stop when @fn returns a non-zero value. The function is
1991 * using RCU to traverse the list and therefore may be usind in atonic
1992 * contexts. The @fn callback is invoked from RCU critical section and
1993 * thus must not sleep.
1994 */
1995int input_handler_for_each_handle(struct input_handler *handler, void *data,
1996				  int (*fn)(struct input_handle *, void *))
1997{
1998	struct input_handle *handle;
1999	int retval = 0;
2000
2001	rcu_read_lock();
2002
2003	list_for_each_entry_rcu(handle, &handler->h_list, h_node) {
2004		retval = fn(handle, data);
2005		if (retval)
2006			break;
2007	}
2008
2009	rcu_read_unlock();
2010
2011	return retval;
2012}
2013EXPORT_SYMBOL(input_handler_for_each_handle);
2014
2015/**
2016 * input_register_handle - register a new input handle
2017 * @handle: handle to register
2018 *
2019 * This function puts a new input handle onto device's
2020 * and handler's lists so that events can flow through
2021 * it once it is opened using input_open_device().
2022 *
2023 * This function is supposed to be called from handler's
2024 * connect() method.
2025 */
2026int input_register_handle(struct input_handle *handle)
2027{
2028	struct input_handler *handler = handle->handler;
2029	struct input_dev *dev = handle->dev;
2030	int error;
2031
2032	/*
2033	 * We take dev->mutex here to prevent race with
2034	 * input_release_device().
2035	 */
2036	error = mutex_lock_interruptible(&dev->mutex);
2037	if (error)
2038		return error;
2039
2040	/*
2041	 * Filters go to the head of the list, normal handlers
2042	 * to the tail.
2043	 */
2044	if (handler->filter)
2045		list_add_rcu(&handle->d_node, &dev->h_list);
2046	else
2047		list_add_tail_rcu(&handle->d_node, &dev->h_list);
2048
2049	mutex_unlock(&dev->mutex);
2050
2051	/*
2052	 * Since we are supposed to be called from ->connect()
2053	 * which is mutually exclusive with ->disconnect()
2054	 * we can't be racing with input_unregister_handle()
2055	 * and so separate lock is not needed here.
2056	 */
2057	list_add_tail_rcu(&handle->h_node, &handler->h_list);
2058
2059	if (handler->start)
2060		handler->start(handle);
2061
2062	return 0;
2063}
2064EXPORT_SYMBOL(input_register_handle);
2065
2066/**
2067 * input_unregister_handle - unregister an input handle
2068 * @handle: handle to unregister
2069 *
2070 * This function removes input handle from device's
2071 * and handler's lists.
2072 *
2073 * This function is supposed to be called from handler's
2074 * disconnect() method.
2075 */
2076void input_unregister_handle(struct input_handle *handle)
2077{
2078	struct input_dev *dev = handle->dev;
2079
2080	list_del_rcu(&handle->h_node);
2081
2082	/*
2083	 * Take dev->mutex to prevent race with input_release_device().
2084	 */
2085	mutex_lock(&dev->mutex);
2086	list_del_rcu(&handle->d_node);
2087	mutex_unlock(&dev->mutex);
2088
2089	synchronize_rcu();
2090}
2091EXPORT_SYMBOL(input_unregister_handle);
2092
2093static int input_open_file(struct inode *inode, struct file *file)
 
 
 
 
 
 
 
 
 
 
 
 
2094{
2095	struct input_handler *handler;
2096	const struct file_operations *old_fops, *new_fops = NULL;
2097	int err;
2098
2099	err = mutex_lock_interruptible(&input_mutex);
2100	if (err)
2101		return err;
2102
2103	/* No load-on-demand here? */
2104	handler = input_table[iminor(inode) >> 5];
2105	if (handler)
2106		new_fops = fops_get(handler->fops);
2107
2108	mutex_unlock(&input_mutex);
2109
2110	/*
2111	 * That's _really_ odd. Usually NULL ->open means "nothing special",
2112	 * not "no device". Oh, well...
 
2113	 */
2114	if (!new_fops || !new_fops->open) {
2115		fops_put(new_fops);
2116		err = -ENODEV;
2117		goto out;
 
 
 
2118	}
2119
2120	old_fops = file->f_op;
2121	file->f_op = new_fops;
2122
2123	err = new_fops->open(inode, file);
2124	if (err) {
2125		fops_put(file->f_op);
2126		file->f_op = fops_get(old_fops);
2127	}
2128	fops_put(old_fops);
2129out:
2130	return err;
2131}
 
2132
2133static const struct file_operations input_fops = {
2134	.owner = THIS_MODULE,
2135	.open = input_open_file,
2136	.llseek = noop_llseek,
2137};
 
 
 
 
 
 
 
2138
2139static int __init input_init(void)
2140{
2141	int err;
2142
2143	err = class_register(&input_class);
2144	if (err) {
2145		pr_err("unable to register input_dev class\n");
2146		return err;
2147	}
2148
2149	err = input_proc_init();
2150	if (err)
2151		goto fail1;
2152
2153	err = register_chrdev(INPUT_MAJOR, "input", &input_fops);
 
2154	if (err) {
2155		pr_err("unable to register char major %d", INPUT_MAJOR);
2156		goto fail2;
2157	}
2158
2159	return 0;
2160
2161 fail2:	input_proc_exit();
2162 fail1:	class_unregister(&input_class);
2163	return err;
2164}
2165
2166static void __exit input_exit(void)
2167{
2168	input_proc_exit();
2169	unregister_chrdev(INPUT_MAJOR, "input");
 
2170	class_unregister(&input_class);
2171}
2172
2173subsys_initcall(input_init);
2174module_exit(input_exit);