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