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v4.10.11
 
   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);
v6.13.7
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * The input core
   4 *
   5 * Copyright (c) 1999-2002 Vojtech Pavlik
   6 */
   7
 
 
 
 
 
   8
   9#define pr_fmt(fmt) KBUILD_BASENAME ": " fmt
  10
  11#include <linux/init.h>
  12#include <linux/types.h>
  13#include <linux/idr.h>
  14#include <linux/input/mt.h>
  15#include <linux/module.h>
  16#include <linux/slab.h>
  17#include <linux/random.h>
  18#include <linux/major.h>
  19#include <linux/proc_fs.h>
  20#include <linux/sched.h>
  21#include <linux/seq_file.h>
  22#include <linux/pm.h>
  23#include <linux/poll.h>
  24#include <linux/device.h>
  25#include <linux/kstrtox.h>
  26#include <linux/mutex.h>
  27#include <linux/rcupdate.h>
  28#include "input-compat.h"
  29#include "input-core-private.h"
  30#include "input-poller.h"
  31
  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 const unsigned int input_max_code[EV_CNT] = {
  54	[EV_KEY] = KEY_MAX,
  55	[EV_REL] = REL_MAX,
  56	[EV_ABS] = ABS_MAX,
  57	[EV_MSC] = MSC_MAX,
  58	[EV_SW] = SW_MAX,
  59	[EV_LED] = LED_MAX,
  60	[EV_SND] = SND_MAX,
  61	[EV_FF] = FF_MAX,
  62};
  63
  64static inline int is_event_supported(unsigned int code,
  65				     unsigned long *bm, unsigned int max)
  66{
  67	return code <= max && test_bit(code, bm);
  68}
  69
  70static int input_defuzz_abs_event(int value, int old_val, int fuzz)
  71{
  72	if (fuzz) {
  73		if (value > old_val - fuzz / 2 && value < old_val + fuzz / 2)
  74			return old_val;
  75
  76		if (value > old_val - fuzz && value < old_val + fuzz)
  77			return (old_val * 3 + value) / 4;
  78
  79		if (value > old_val - fuzz * 2 && value < old_val + fuzz * 2)
  80			return (old_val + value) / 2;
  81	}
  82
  83	return value;
  84}
  85
  86static void input_start_autorepeat(struct input_dev *dev, int code)
  87{
  88	if (test_bit(EV_REP, dev->evbit) &&
  89	    dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] &&
  90	    dev->timer.function) {
  91		dev->repeat_key = code;
  92		mod_timer(&dev->timer,
  93			  jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
  94	}
  95}
  96
  97static void input_stop_autorepeat(struct input_dev *dev)
  98{
  99	del_timer(&dev->timer);
 100}
 101
 102/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 103 * Pass values first through all filters and then, if event has not been
 104 * filtered out, through all open handles. This order is achieved by placing
 105 * filters at the head of the list of handles attached to the device, and
 106 * placing regular handles at the tail of the list.
 107 *
 108 * This function is called with dev->event_lock held and interrupts disabled.
 109 */
 110static void input_pass_values(struct input_dev *dev,
 111			      struct input_value *vals, unsigned int count)
 112{
 113	struct input_handle *handle;
 114	struct input_value *v;
 115
 116	lockdep_assert_held(&dev->event_lock);
 
 117
 118	rcu_read_lock();
 119
 120	handle = rcu_dereference(dev->grab);
 121	if (handle) {
 122		count = handle->handle_events(handle, vals, count);
 123	} else {
 124		list_for_each_entry_rcu(handle, &dev->h_list, d_node)
 125			if (handle->open) {
 126				count = handle->handle_events(handle, vals,
 127							      count);
 128				if (!count)
 129					break;
 130			}
 131	}
 132
 133	rcu_read_unlock();
 134
 135	/* trigger auto repeat for key events */
 136	if (test_bit(EV_REP, dev->evbit) && test_bit(EV_KEY, dev->evbit)) {
 137		for (v = vals; v != vals + count; v++) {
 138			if (v->type == EV_KEY && v->value != 2) {
 139				if (v->value)
 140					input_start_autorepeat(dev, v->code);
 141				else
 142					input_stop_autorepeat(dev);
 143			}
 144		}
 145	}
 146}
 147
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 148#define INPUT_IGNORE_EVENT	0
 149#define INPUT_PASS_TO_HANDLERS	1
 150#define INPUT_PASS_TO_DEVICE	2
 151#define INPUT_SLOT		4
 152#define INPUT_FLUSH		8
 153#define INPUT_PASS_TO_ALL	(INPUT_PASS_TO_HANDLERS | INPUT_PASS_TO_DEVICE)
 154
 155static int input_handle_abs_event(struct input_dev *dev,
 156				  unsigned int code, int *pval)
 157{
 158	struct input_mt *mt = dev->mt;
 159	bool is_new_slot = false;
 160	bool is_mt_event;
 161	int *pold;
 162
 163	if (code == ABS_MT_SLOT) {
 164		/*
 165		 * "Stage" the event; we'll flush it later, when we
 166		 * get actual touch data.
 167		 */
 168		if (mt && *pval >= 0 && *pval < mt->num_slots)
 169			mt->slot = *pval;
 170
 171		return INPUT_IGNORE_EVENT;
 172	}
 173
 174	is_mt_event = input_is_mt_value(code);
 175
 176	if (!is_mt_event) {
 177		pold = &dev->absinfo[code].value;
 178	} else if (mt) {
 179		pold = &mt->slots[mt->slot].abs[code - ABS_MT_FIRST];
 180		is_new_slot = mt->slot != dev->absinfo[ABS_MT_SLOT].value;
 181	} else {
 182		/*
 183		 * Bypass filtering for multi-touch events when
 184		 * not employing slots.
 185		 */
 186		pold = NULL;
 187	}
 188
 189	if (pold) {
 190		*pval = input_defuzz_abs_event(*pval, *pold,
 191						dev->absinfo[code].fuzz);
 192		if (*pold == *pval)
 193			return INPUT_IGNORE_EVENT;
 194
 195		*pold = *pval;
 196	}
 197
 198	/* Flush pending "slot" event */
 199	if (is_new_slot) {
 200		dev->absinfo[ABS_MT_SLOT].value = mt->slot;
 201		return INPUT_PASS_TO_HANDLERS | INPUT_SLOT;
 202	}
 203
 204	return INPUT_PASS_TO_HANDLERS;
 205}
 206
 207static int input_get_disposition(struct input_dev *dev,
 208			  unsigned int type, unsigned int code, int *pval)
 209{
 210	int disposition = INPUT_IGNORE_EVENT;
 211	int value = *pval;
 212
 213	/* filter-out events from inhibited devices */
 214	if (dev->inhibited)
 215		return INPUT_IGNORE_EVENT;
 216
 217	switch (type) {
 218
 219	case EV_SYN:
 220		switch (code) {
 221		case SYN_CONFIG:
 222			disposition = INPUT_PASS_TO_ALL;
 223			break;
 224
 225		case SYN_REPORT:
 226			disposition = INPUT_PASS_TO_HANDLERS | INPUT_FLUSH;
 227			break;
 228		case SYN_MT_REPORT:
 229			disposition = INPUT_PASS_TO_HANDLERS;
 230			break;
 231		}
 232		break;
 233
 234	case EV_KEY:
 235		if (is_event_supported(code, dev->keybit, KEY_MAX)) {
 236
 237			/* auto-repeat bypasses state updates */
 238			if (value == 2) {
 239				disposition = INPUT_PASS_TO_HANDLERS;
 240				break;
 241			}
 242
 243			if (!!test_bit(code, dev->key) != !!value) {
 244
 245				__change_bit(code, dev->key);
 246				disposition = INPUT_PASS_TO_HANDLERS;
 247			}
 248		}
 249		break;
 250
 251	case EV_SW:
 252		if (is_event_supported(code, dev->swbit, SW_MAX) &&
 253		    !!test_bit(code, dev->sw) != !!value) {
 254
 255			__change_bit(code, dev->sw);
 256			disposition = INPUT_PASS_TO_HANDLERS;
 257		}
 258		break;
 259
 260	case EV_ABS:
 261		if (is_event_supported(code, dev->absbit, ABS_MAX))
 262			disposition = input_handle_abs_event(dev, code, &value);
 263
 264		break;
 265
 266	case EV_REL:
 267		if (is_event_supported(code, dev->relbit, REL_MAX) && value)
 268			disposition = INPUT_PASS_TO_HANDLERS;
 269
 270		break;
 271
 272	case EV_MSC:
 273		if (is_event_supported(code, dev->mscbit, MSC_MAX))
 274			disposition = INPUT_PASS_TO_ALL;
 275
 276		break;
 277
 278	case EV_LED:
 279		if (is_event_supported(code, dev->ledbit, LED_MAX) &&
 280		    !!test_bit(code, dev->led) != !!value) {
 281
 282			__change_bit(code, dev->led);
 283			disposition = INPUT_PASS_TO_ALL;
 284		}
 285		break;
 286
 287	case EV_SND:
 288		if (is_event_supported(code, dev->sndbit, SND_MAX)) {
 289
 290			if (!!test_bit(code, dev->snd) != !!value)
 291				__change_bit(code, dev->snd);
 292			disposition = INPUT_PASS_TO_ALL;
 293		}
 294		break;
 295
 296	case EV_REP:
 297		if (code <= REP_MAX && value >= 0 && dev->rep[code] != value) {
 298			dev->rep[code] = value;
 299			disposition = INPUT_PASS_TO_ALL;
 300		}
 301		break;
 302
 303	case EV_FF:
 304		if (value >= 0)
 305			disposition = INPUT_PASS_TO_ALL;
 306		break;
 307
 308	case EV_PWR:
 309		disposition = INPUT_PASS_TO_ALL;
 310		break;
 311	}
 312
 313	*pval = value;
 314	return disposition;
 315}
 316
 317static void input_event_dispose(struct input_dev *dev, int disposition,
 318				unsigned int type, unsigned int code, int value)
 319{
 
 
 
 
 
 320	if ((disposition & INPUT_PASS_TO_DEVICE) && dev->event)
 321		dev->event(dev, type, code, value);
 322
 
 
 
 323	if (disposition & INPUT_PASS_TO_HANDLERS) {
 324		struct input_value *v;
 325
 326		if (disposition & INPUT_SLOT) {
 327			v = &dev->vals[dev->num_vals++];
 328			v->type = EV_ABS;
 329			v->code = ABS_MT_SLOT;
 330			v->value = dev->mt->slot;
 331		}
 332
 333		v = &dev->vals[dev->num_vals++];
 334		v->type = type;
 335		v->code = code;
 336		v->value = value;
 337	}
 338
 339	if (disposition & INPUT_FLUSH) {
 340		if (dev->num_vals >= 2)
 341			input_pass_values(dev, dev->vals, dev->num_vals);
 342		dev->num_vals = 0;
 343		/*
 344		 * Reset the timestamp on flush so we won't end up
 345		 * with a stale one. Note we only need to reset the
 346		 * monolithic one as we use its presence when deciding
 347		 * whether to generate a synthetic timestamp.
 348		 */
 349		dev->timestamp[INPUT_CLK_MONO] = ktime_set(0, 0);
 350	} else if (dev->num_vals >= dev->max_vals - 2) {
 351		dev->vals[dev->num_vals++] = input_value_sync;
 352		input_pass_values(dev, dev->vals, dev->num_vals);
 353		dev->num_vals = 0;
 354	}
 355}
 356
 357void input_handle_event(struct input_dev *dev,
 358			unsigned int type, unsigned int code, int value)
 359{
 360	int disposition;
 361
 362	lockdep_assert_held(&dev->event_lock);
 363
 364	disposition = input_get_disposition(dev, type, code, &value);
 365	if (disposition != INPUT_IGNORE_EVENT) {
 366		if (type != EV_SYN)
 367			add_input_randomness(type, code, value);
 368
 369		input_event_dispose(dev, disposition, type, code, value);
 370	}
 371}
 372
 373/**
 374 * input_event() - report new input event
 375 * @dev: device that generated the event
 376 * @type: type of the event
 377 * @code: event code
 378 * @value: value of the event
 379 *
 380 * This function should be used by drivers implementing various input
 381 * devices to report input events. See also input_inject_event().
 382 *
 383 * NOTE: input_event() may be safely used right after input device was
 384 * allocated with input_allocate_device(), even before it is registered
 385 * with input_register_device(), but the event will not reach any of the
 386 * input handlers. Such early invocation of input_event() may be used
 387 * to 'seed' initial state of a switch or initial position of absolute
 388 * axis, etc.
 389 */
 390void input_event(struct input_dev *dev,
 391		 unsigned int type, unsigned int code, int value)
 392{
 393	unsigned long flags;
 394
 395	if (is_event_supported(type, dev->evbit, EV_MAX)) {
 396
 397		spin_lock_irqsave(&dev->event_lock, flags);
 398		input_handle_event(dev, type, code, value);
 399		spin_unlock_irqrestore(&dev->event_lock, flags);
 400	}
 401}
 402EXPORT_SYMBOL(input_event);
 403
 404/**
 405 * input_inject_event() - send input event from input handler
 406 * @handle: input handle to send event through
 407 * @type: type of the event
 408 * @code: event code
 409 * @value: value of the event
 410 *
 411 * Similar to input_event() but will ignore event if device is
 412 * "grabbed" and handle injecting event is not the one that owns
 413 * the device.
 414 */
 415void input_inject_event(struct input_handle *handle,
 416			unsigned int type, unsigned int code, int value)
 417{
 418	struct input_dev *dev = handle->dev;
 419	struct input_handle *grab;
 420	unsigned long flags;
 421
 422	if (is_event_supported(type, dev->evbit, EV_MAX)) {
 423		spin_lock_irqsave(&dev->event_lock, flags);
 424
 425		rcu_read_lock();
 426		grab = rcu_dereference(dev->grab);
 427		if (!grab || grab == handle)
 428			input_handle_event(dev, type, code, value);
 429		rcu_read_unlock();
 430
 431		spin_unlock_irqrestore(&dev->event_lock, flags);
 432	}
 433}
 434EXPORT_SYMBOL(input_inject_event);
 435
 436/**
 437 * input_alloc_absinfo - allocates array of input_absinfo structs
 438 * @dev: the input device emitting absolute events
 439 *
 440 * If the absinfo struct the caller asked for is already allocated, this
 441 * functions will not do anything.
 442 */
 443void input_alloc_absinfo(struct input_dev *dev)
 444{
 445	if (dev->absinfo)
 446		return;
 
 447
 448	dev->absinfo = kcalloc(ABS_CNT, sizeof(*dev->absinfo), GFP_KERNEL);
 449	if (!dev->absinfo) {
 450		dev_err(dev->dev.parent ?: &dev->dev,
 451			"%s: unable to allocate memory\n", __func__);
 452		/*
 453		 * We will handle this allocation failure in
 454		 * input_register_device() when we refuse to register input
 455		 * device with ABS bits but without absinfo.
 456		 */
 457	}
 458}
 459EXPORT_SYMBOL(input_alloc_absinfo);
 460
 461void input_set_abs_params(struct input_dev *dev, unsigned int axis,
 462			  int min, int max, int fuzz, int flat)
 463{
 464	struct input_absinfo *absinfo;
 465
 466	__set_bit(EV_ABS, dev->evbit);
 467	__set_bit(axis, dev->absbit);
 468
 469	input_alloc_absinfo(dev);
 470	if (!dev->absinfo)
 471		return;
 472
 473	absinfo = &dev->absinfo[axis];
 474	absinfo->minimum = min;
 475	absinfo->maximum = max;
 476	absinfo->fuzz = fuzz;
 477	absinfo->flat = flat;
 
 
 
 478}
 479EXPORT_SYMBOL(input_set_abs_params);
 480
 481/**
 482 * input_copy_abs - Copy absinfo from one input_dev to another
 483 * @dst: Destination input device to copy the abs settings to
 484 * @dst_axis: ABS_* value selecting the destination axis
 485 * @src: Source input device to copy the abs settings from
 486 * @src_axis: ABS_* value selecting the source axis
 487 *
 488 * Set absinfo for the selected destination axis by copying it from
 489 * the specified source input device's source axis.
 490 * This is useful to e.g. setup a pen/stylus input-device for combined
 491 * touchscreen/pen hardware where the pen uses the same coordinates as
 492 * the touchscreen.
 493 */
 494void input_copy_abs(struct input_dev *dst, unsigned int dst_axis,
 495		    const struct input_dev *src, unsigned int src_axis)
 496{
 497	/* src must have EV_ABS and src_axis set */
 498	if (WARN_ON(!(test_bit(EV_ABS, src->evbit) &&
 499		      test_bit(src_axis, src->absbit))))
 500		return;
 501
 502	/*
 503	 * input_alloc_absinfo() may have failed for the source. Our caller is
 504	 * expected to catch this when registering the input devices, which may
 505	 * happen after the input_copy_abs() call.
 506	 */
 507	if (!src->absinfo)
 508		return;
 509
 510	input_set_capability(dst, EV_ABS, dst_axis);
 511	if (!dst->absinfo)
 512		return;
 513
 514	dst->absinfo[dst_axis] = src->absinfo[src_axis];
 515}
 516EXPORT_SYMBOL(input_copy_abs);
 517
 518/**
 519 * input_grab_device - grabs device for exclusive use
 520 * @handle: input handle that wants to own the device
 521 *
 522 * When a device is grabbed by an input handle all events generated by
 523 * the device are delivered only to this handle. Also events injected
 524 * by other input handles are ignored while device is grabbed.
 525 */
 526int input_grab_device(struct input_handle *handle)
 527{
 528	struct input_dev *dev = handle->dev;
 529	int retval;
 530
 531	retval = mutex_lock_interruptible(&dev->mutex);
 532	if (retval)
 533		return retval;
 534
 535	if (dev->grab) {
 536		retval = -EBUSY;
 537		goto out;
 538	}
 539
 540	rcu_assign_pointer(dev->grab, handle);
 541
 542 out:
 543	mutex_unlock(&dev->mutex);
 544	return retval;
 545}
 546EXPORT_SYMBOL(input_grab_device);
 547
 548static void __input_release_device(struct input_handle *handle)
 549{
 550	struct input_dev *dev = handle->dev;
 551	struct input_handle *grabber;
 552
 553	grabber = rcu_dereference_protected(dev->grab,
 554					    lockdep_is_held(&dev->mutex));
 555	if (grabber == handle) {
 556		rcu_assign_pointer(dev->grab, NULL);
 557		/* Make sure input_pass_values() notices that grab is gone */
 558		synchronize_rcu();
 559
 560		list_for_each_entry(handle, &dev->h_list, d_node)
 561			if (handle->open && handle->handler->start)
 562				handle->handler->start(handle);
 563	}
 564}
 565
 566/**
 567 * input_release_device - release previously grabbed device
 568 * @handle: input handle that owns the device
 569 *
 570 * Releases previously grabbed device so that other input handles can
 571 * start receiving input events. Upon release all handlers attached
 572 * to the device have their start() method called so they have a change
 573 * to synchronize device state with the rest of the system.
 574 */
 575void input_release_device(struct input_handle *handle)
 576{
 577	struct input_dev *dev = handle->dev;
 578
 579	mutex_lock(&dev->mutex);
 580	__input_release_device(handle);
 581	mutex_unlock(&dev->mutex);
 582}
 583EXPORT_SYMBOL(input_release_device);
 584
 585/**
 586 * input_open_device - open input device
 587 * @handle: handle through which device is being accessed
 588 *
 589 * This function should be called by input handlers when they
 590 * want to start receive events from given input device.
 591 */
 592int input_open_device(struct input_handle *handle)
 593{
 594	struct input_dev *dev = handle->dev;
 595	int retval;
 596
 597	retval = mutex_lock_interruptible(&dev->mutex);
 598	if (retval)
 599		return retval;
 600
 601	if (dev->going_away) {
 602		retval = -ENODEV;
 603		goto out;
 604	}
 605
 606	handle->open++;
 607
 608	if (handle->handler->passive_observer)
 609		goto out;
 610
 611	if (dev->users++ || dev->inhibited) {
 612		/*
 613		 * Device is already opened and/or inhibited,
 614		 * so we can exit immediately and report success.
 615		 */
 616		goto out;
 617	}
 618
 619	if (dev->open) {
 620		retval = dev->open(dev);
 621		if (retval) {
 622			dev->users--;
 623			handle->open--;
 624			/*
 625			 * Make sure we are not delivering any more events
 626			 * through this handle
 627			 */
 628			synchronize_rcu();
 629			goto out;
 630		}
 631	}
 632
 633	if (dev->poller)
 634		input_dev_poller_start(dev->poller);
 635
 636 out:
 637	mutex_unlock(&dev->mutex);
 638	return retval;
 639}
 640EXPORT_SYMBOL(input_open_device);
 641
 642int input_flush_device(struct input_handle *handle, struct file *file)
 643{
 644	struct input_dev *dev = handle->dev;
 645	int retval;
 646
 647	retval = mutex_lock_interruptible(&dev->mutex);
 648	if (retval)
 649		return retval;
 650
 651	if (dev->flush)
 652		retval = dev->flush(dev, file);
 653
 654	mutex_unlock(&dev->mutex);
 655	return retval;
 656}
 657EXPORT_SYMBOL(input_flush_device);
 658
 659/**
 660 * input_close_device - close input device
 661 * @handle: handle through which device is being accessed
 662 *
 663 * This function should be called by input handlers when they
 664 * want to stop receive events from given input device.
 665 */
 666void input_close_device(struct input_handle *handle)
 667{
 668	struct input_dev *dev = handle->dev;
 669
 670	mutex_lock(&dev->mutex);
 671
 672	__input_release_device(handle);
 673
 674	if (!handle->handler->passive_observer) {
 675		if (!--dev->users && !dev->inhibited) {
 676			if (dev->poller)
 677				input_dev_poller_stop(dev->poller);
 678			if (dev->close)
 679				dev->close(dev);
 680		}
 681	}
 682
 683	if (!--handle->open) {
 684		/*
 685		 * synchronize_rcu() makes sure that input_pass_values()
 686		 * completed and that no more input events are delivered
 687		 * through this handle
 688		 */
 689		synchronize_rcu();
 690	}
 691
 692	mutex_unlock(&dev->mutex);
 693}
 694EXPORT_SYMBOL(input_close_device);
 695
 696/*
 697 * Simulate keyup events for all keys that are marked as pressed.
 698 * The function must be called with dev->event_lock held.
 699 */
 700static bool input_dev_release_keys(struct input_dev *dev)
 701{
 702	bool need_sync = false;
 703	int code;
 704
 705	lockdep_assert_held(&dev->event_lock);
 706
 707	if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
 708		for_each_set_bit(code, dev->key, KEY_CNT) {
 709			input_handle_event(dev, EV_KEY, code, 0);
 710			need_sync = true;
 711		}
 
 
 
 
 
 712	}
 713
 714	return need_sync;
 715}
 716
 717/*
 718 * Prepare device for unregistering
 719 */
 720static void input_disconnect_device(struct input_dev *dev)
 721{
 722	struct input_handle *handle;
 723
 724	/*
 725	 * Mark device as going away. Note that we take dev->mutex here
 726	 * not to protect access to dev->going_away but rather to ensure
 727	 * that there are no threads in the middle of input_open_device()
 728	 */
 729	mutex_lock(&dev->mutex);
 730	dev->going_away = true;
 731	mutex_unlock(&dev->mutex);
 732
 733	spin_lock_irq(&dev->event_lock);
 734
 735	/*
 736	 * Simulate keyup events for all pressed keys so that handlers
 737	 * are not left with "stuck" keys. The driver may continue
 738	 * generate events even after we done here but they will not
 739	 * reach any handlers.
 740	 */
 741	if (input_dev_release_keys(dev))
 742		input_handle_event(dev, EV_SYN, SYN_REPORT, 1);
 743
 744	list_for_each_entry(handle, &dev->h_list, d_node)
 745		handle->open = 0;
 746
 747	spin_unlock_irq(&dev->event_lock);
 748}
 749
 750/**
 751 * input_scancode_to_scalar() - converts scancode in &struct input_keymap_entry
 752 * @ke: keymap entry containing scancode to be converted.
 753 * @scancode: pointer to the location where converted scancode should
 754 *	be stored.
 755 *
 756 * This function is used to convert scancode stored in &struct keymap_entry
 757 * into scalar form understood by legacy keymap handling methods. These
 758 * methods expect scancodes to be represented as 'unsigned int'.
 759 */
 760int input_scancode_to_scalar(const struct input_keymap_entry *ke,
 761			     unsigned int *scancode)
 762{
 763	switch (ke->len) {
 764	case 1:
 765		*scancode = *((u8 *)ke->scancode);
 766		break;
 767
 768	case 2:
 769		*scancode = *((u16 *)ke->scancode);
 770		break;
 771
 772	case 4:
 773		*scancode = *((u32 *)ke->scancode);
 774		break;
 775
 776	default:
 777		return -EINVAL;
 778	}
 779
 780	return 0;
 781}
 782EXPORT_SYMBOL(input_scancode_to_scalar);
 783
 784/*
 785 * Those routines handle the default case where no [gs]etkeycode() is
 786 * defined. In this case, an array indexed by the scancode is used.
 787 */
 788
 789static unsigned int input_fetch_keycode(struct input_dev *dev,
 790					unsigned int index)
 791{
 792	switch (dev->keycodesize) {
 793	case 1:
 794		return ((u8 *)dev->keycode)[index];
 795
 796	case 2:
 797		return ((u16 *)dev->keycode)[index];
 798
 799	default:
 800		return ((u32 *)dev->keycode)[index];
 801	}
 802}
 803
 804static int input_default_getkeycode(struct input_dev *dev,
 805				    struct input_keymap_entry *ke)
 806{
 807	unsigned int index;
 808	int error;
 809
 810	if (!dev->keycodesize)
 811		return -EINVAL;
 812
 813	if (ke->flags & INPUT_KEYMAP_BY_INDEX)
 814		index = ke->index;
 815	else {
 816		error = input_scancode_to_scalar(ke, &index);
 817		if (error)
 818			return error;
 819	}
 820
 821	if (index >= dev->keycodemax)
 822		return -EINVAL;
 823
 824	ke->keycode = input_fetch_keycode(dev, index);
 825	ke->index = index;
 826	ke->len = sizeof(index);
 827	memcpy(ke->scancode, &index, sizeof(index));
 828
 829	return 0;
 830}
 831
 832static int input_default_setkeycode(struct input_dev *dev,
 833				    const struct input_keymap_entry *ke,
 834				    unsigned int *old_keycode)
 835{
 836	unsigned int index;
 837	int error;
 838	int i;
 839
 840	if (!dev->keycodesize)
 841		return -EINVAL;
 842
 843	if (ke->flags & INPUT_KEYMAP_BY_INDEX) {
 844		index = ke->index;
 845	} else {
 846		error = input_scancode_to_scalar(ke, &index);
 847		if (error)
 848			return error;
 849	}
 850
 851	if (index >= dev->keycodemax)
 852		return -EINVAL;
 853
 854	if (dev->keycodesize < sizeof(ke->keycode) &&
 855			(ke->keycode >> (dev->keycodesize * 8)))
 856		return -EINVAL;
 857
 858	switch (dev->keycodesize) {
 859		case 1: {
 860			u8 *k = (u8 *)dev->keycode;
 861			*old_keycode = k[index];
 862			k[index] = ke->keycode;
 863			break;
 864		}
 865		case 2: {
 866			u16 *k = (u16 *)dev->keycode;
 867			*old_keycode = k[index];
 868			k[index] = ke->keycode;
 869			break;
 870		}
 871		default: {
 872			u32 *k = (u32 *)dev->keycode;
 873			*old_keycode = k[index];
 874			k[index] = ke->keycode;
 875			break;
 876		}
 877	}
 878
 879	if (*old_keycode <= KEY_MAX) {
 880		__clear_bit(*old_keycode, dev->keybit);
 881		for (i = 0; i < dev->keycodemax; i++) {
 882			if (input_fetch_keycode(dev, i) == *old_keycode) {
 883				__set_bit(*old_keycode, dev->keybit);
 884				/* Setting the bit twice is useless, so break */
 885				break;
 886			}
 887		}
 888	}
 889
 890	__set_bit(ke->keycode, dev->keybit);
 891	return 0;
 892}
 893
 894/**
 895 * input_get_keycode - retrieve keycode currently mapped to a given scancode
 896 * @dev: input device which keymap is being queried
 897 * @ke: keymap entry
 898 *
 899 * This function should be called by anyone interested in retrieving current
 900 * keymap. Presently evdev handlers use it.
 901 */
 902int input_get_keycode(struct input_dev *dev, struct input_keymap_entry *ke)
 903{
 904	unsigned long flags;
 905	int retval;
 906
 907	spin_lock_irqsave(&dev->event_lock, flags);
 908	retval = dev->getkeycode(dev, ke);
 909	spin_unlock_irqrestore(&dev->event_lock, flags);
 910
 911	return retval;
 912}
 913EXPORT_SYMBOL(input_get_keycode);
 914
 915/**
 916 * input_set_keycode - attribute a keycode to a given scancode
 917 * @dev: input device which keymap is being updated
 918 * @ke: new keymap entry
 919 *
 920 * This function should be called by anyone needing to update current
 921 * keymap. Presently keyboard and evdev handlers use it.
 922 */
 923int input_set_keycode(struct input_dev *dev,
 924		      const struct input_keymap_entry *ke)
 925{
 926	unsigned long flags;
 927	unsigned int old_keycode;
 928	int retval;
 929
 930	if (ke->keycode > KEY_MAX)
 931		return -EINVAL;
 932
 933	spin_lock_irqsave(&dev->event_lock, flags);
 934
 935	retval = dev->setkeycode(dev, ke, &old_keycode);
 936	if (retval)
 937		goto out;
 938
 939	/* Make sure KEY_RESERVED did not get enabled. */
 940	__clear_bit(KEY_RESERVED, dev->keybit);
 941
 942	/*
 943	 * Simulate keyup event if keycode is not present
 944	 * in the keymap anymore
 945	 */
 946	if (old_keycode > KEY_MAX) {
 947		dev_warn(dev->dev.parent ?: &dev->dev,
 948			 "%s: got too big old keycode %#x\n",
 949			 __func__, old_keycode);
 950	} else if (test_bit(EV_KEY, dev->evbit) &&
 951		   !is_event_supported(old_keycode, dev->keybit, KEY_MAX) &&
 952		   __test_and_clear_bit(old_keycode, dev->key)) {
 953		/*
 954		 * We have to use input_event_dispose() here directly instead
 955		 * of input_handle_event() because the key we want to release
 956		 * here is considered no longer supported by the device and
 957		 * input_handle_event() will ignore it.
 958		 */
 959		input_event_dispose(dev, INPUT_PASS_TO_HANDLERS,
 960				    EV_KEY, old_keycode, 0);
 961		input_event_dispose(dev, INPUT_PASS_TO_HANDLERS | INPUT_FLUSH,
 962				    EV_SYN, SYN_REPORT, 1);
 963	}
 964
 965 out:
 966	spin_unlock_irqrestore(&dev->event_lock, flags);
 967
 968	return retval;
 969}
 970EXPORT_SYMBOL(input_set_keycode);
 971
 972bool input_match_device_id(const struct input_dev *dev,
 973			   const struct input_device_id *id)
 974{
 975	if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
 976		if (id->bustype != dev->id.bustype)
 977			return false;
 978
 979	if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
 980		if (id->vendor != dev->id.vendor)
 981			return false;
 982
 983	if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
 984		if (id->product != dev->id.product)
 985			return false;
 986
 987	if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
 988		if (id->version != dev->id.version)
 989			return false;
 990
 991	if (!bitmap_subset(id->evbit, dev->evbit, EV_MAX) ||
 992	    !bitmap_subset(id->keybit, dev->keybit, KEY_MAX) ||
 993	    !bitmap_subset(id->relbit, dev->relbit, REL_MAX) ||
 994	    !bitmap_subset(id->absbit, dev->absbit, ABS_MAX) ||
 995	    !bitmap_subset(id->mscbit, dev->mscbit, MSC_MAX) ||
 996	    !bitmap_subset(id->ledbit, dev->ledbit, LED_MAX) ||
 997	    !bitmap_subset(id->sndbit, dev->sndbit, SND_MAX) ||
 998	    !bitmap_subset(id->ffbit, dev->ffbit, FF_MAX) ||
 999	    !bitmap_subset(id->swbit, dev->swbit, SW_MAX) ||
1000	    !bitmap_subset(id->propbit, dev->propbit, INPUT_PROP_MAX)) {
1001		return false;
1002	}
1003
1004	return true;
1005}
1006EXPORT_SYMBOL(input_match_device_id);
1007
1008static const struct input_device_id *input_match_device(struct input_handler *handler,
1009							struct input_dev *dev)
1010{
1011	const struct input_device_id *id;
1012
1013	for (id = handler->id_table; id->flags || id->driver_info; id++) {
1014		if (input_match_device_id(dev, id) &&
1015		    (!handler->match || handler->match(handler, dev))) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1016			return id;
1017		}
1018	}
1019
1020	return NULL;
1021}
1022
1023static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
1024{
1025	const struct input_device_id *id;
1026	int error;
1027
1028	id = input_match_device(handler, dev);
1029	if (!id)
1030		return -ENODEV;
1031
1032	error = handler->connect(handler, dev, id);
1033	if (error && error != -ENODEV)
1034		pr_err("failed to attach handler %s to device %s, error: %d\n",
1035		       handler->name, kobject_name(&dev->dev.kobj), error);
1036
1037	return error;
1038}
1039
1040#ifdef CONFIG_COMPAT
1041
1042static int input_bits_to_string(char *buf, int buf_size,
1043				unsigned long bits, bool skip_empty)
1044{
1045	int len = 0;
1046
1047	if (in_compat_syscall()) {
1048		u32 dword = bits >> 32;
1049		if (dword || !skip_empty)
1050			len += snprintf(buf, buf_size, "%x ", dword);
1051
1052		dword = bits & 0xffffffffUL;
1053		if (dword || !skip_empty || len)
1054			len += snprintf(buf + len, max(buf_size - len, 0),
1055					"%x", dword);
1056	} else {
1057		if (bits || !skip_empty)
1058			len += snprintf(buf, buf_size, "%lx", bits);
1059	}
1060
1061	return len;
1062}
1063
1064#else /* !CONFIG_COMPAT */
1065
1066static int input_bits_to_string(char *buf, int buf_size,
1067				unsigned long bits, bool skip_empty)
1068{
1069	return bits || !skip_empty ?
1070		snprintf(buf, buf_size, "%lx", bits) : 0;
1071}
1072
1073#endif
1074
1075#ifdef CONFIG_PROC_FS
1076
1077static struct proc_dir_entry *proc_bus_input_dir;
1078static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
1079static int input_devices_state;
1080
1081static inline void input_wakeup_procfs_readers(void)
1082{
1083	input_devices_state++;
1084	wake_up(&input_devices_poll_wait);
1085}
1086
1087struct input_seq_state {
1088	unsigned short pos;
1089	bool mutex_acquired;
1090	int input_devices_state;
1091};
1092
1093static __poll_t input_proc_devices_poll(struct file *file, poll_table *wait)
1094{
1095	struct seq_file *seq = file->private_data;
1096	struct input_seq_state *state = seq->private;
1097
1098	poll_wait(file, &input_devices_poll_wait, wait);
1099	if (state->input_devices_state != input_devices_state) {
1100		state->input_devices_state = input_devices_state;
1101		return EPOLLIN | EPOLLRDNORM;
1102	}
1103
1104	return 0;
1105}
1106
 
 
 
 
 
 
 
 
1107static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
1108{
1109	struct input_seq_state *state = seq->private;
1110	int error;
1111
 
 
 
1112	error = mutex_lock_interruptible(&input_mutex);
1113	if (error) {
1114		state->mutex_acquired = false;
1115		return ERR_PTR(error);
1116	}
1117
1118	state->mutex_acquired = true;
1119
1120	return seq_list_start(&input_dev_list, *pos);
1121}
1122
1123static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1124{
1125	return seq_list_next(v, &input_dev_list, pos);
1126}
1127
1128static void input_seq_stop(struct seq_file *seq, void *v)
1129{
1130	struct input_seq_state *state = seq->private;
1131
1132	if (state->mutex_acquired)
1133		mutex_unlock(&input_mutex);
1134}
1135
1136static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
1137				   unsigned long *bitmap, int max)
1138{
1139	int i;
1140	bool skip_empty = true;
1141	char buf[18];
1142
1143	seq_printf(seq, "B: %s=", name);
1144
1145	for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1146		if (input_bits_to_string(buf, sizeof(buf),
1147					 bitmap[i], skip_empty)) {
1148			skip_empty = false;
1149			seq_printf(seq, "%s%s", buf, i > 0 ? " " : "");
1150		}
1151	}
1152
1153	/*
1154	 * If no output was produced print a single 0.
1155	 */
1156	if (skip_empty)
1157		seq_putc(seq, '0');
1158
1159	seq_putc(seq, '\n');
1160}
1161
1162static int input_devices_seq_show(struct seq_file *seq, void *v)
1163{
1164	struct input_dev *dev = container_of(v, struct input_dev, node);
1165	const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1166	struct input_handle *handle;
1167
1168	seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
1169		   dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
1170
1171	seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
1172	seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
1173	seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
1174	seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
1175	seq_puts(seq, "H: Handlers=");
1176
1177	list_for_each_entry(handle, &dev->h_list, d_node)
1178		seq_printf(seq, "%s ", handle->name);
1179	seq_putc(seq, '\n');
1180
1181	input_seq_print_bitmap(seq, "PROP", dev->propbit, INPUT_PROP_MAX);
1182
1183	input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
1184	if (test_bit(EV_KEY, dev->evbit))
1185		input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
1186	if (test_bit(EV_REL, dev->evbit))
1187		input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
1188	if (test_bit(EV_ABS, dev->evbit))
1189		input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
1190	if (test_bit(EV_MSC, dev->evbit))
1191		input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
1192	if (test_bit(EV_LED, dev->evbit))
1193		input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
1194	if (test_bit(EV_SND, dev->evbit))
1195		input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
1196	if (test_bit(EV_FF, dev->evbit))
1197		input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
1198	if (test_bit(EV_SW, dev->evbit))
1199		input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);
1200
1201	seq_putc(seq, '\n');
1202
1203	kfree(path);
1204	return 0;
1205}
1206
1207static const struct seq_operations input_devices_seq_ops = {
1208	.start	= input_devices_seq_start,
1209	.next	= input_devices_seq_next,
1210	.stop	= input_seq_stop,
1211	.show	= input_devices_seq_show,
1212};
1213
1214static int input_proc_devices_open(struct inode *inode, struct file *file)
1215{
1216	return seq_open_private(file, &input_devices_seq_ops,
1217				sizeof(struct input_seq_state));
1218}
1219
1220static const struct proc_ops input_devices_proc_ops = {
1221	.proc_open	= input_proc_devices_open,
1222	.proc_poll	= input_proc_devices_poll,
1223	.proc_read	= seq_read,
1224	.proc_lseek	= seq_lseek,
1225	.proc_release	= seq_release_private,
 
1226};
1227
1228static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
1229{
1230	struct input_seq_state *state = seq->private;
1231	int error;
1232
 
 
 
1233	error = mutex_lock_interruptible(&input_mutex);
1234	if (error) {
1235		state->mutex_acquired = false;
1236		return ERR_PTR(error);
1237	}
1238
1239	state->mutex_acquired = true;
1240	state->pos = *pos;
1241
1242	return seq_list_start(&input_handler_list, *pos);
1243}
1244
1245static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1246{
1247	struct input_seq_state *state = seq->private;
1248
1249	state->pos = *pos + 1;
1250	return seq_list_next(v, &input_handler_list, pos);
1251}
1252
1253static int input_handlers_seq_show(struct seq_file *seq, void *v)
1254{
1255	struct input_handler *handler = container_of(v, struct input_handler, node);
1256	struct input_seq_state *state = seq->private;
1257
1258	seq_printf(seq, "N: Number=%u Name=%s", state->pos, handler->name);
1259	if (handler->filter)
1260		seq_puts(seq, " (filter)");
1261	if (handler->legacy_minors)
1262		seq_printf(seq, " Minor=%d", handler->minor);
1263	seq_putc(seq, '\n');
1264
1265	return 0;
1266}
1267
1268static const struct seq_operations input_handlers_seq_ops = {
1269	.start	= input_handlers_seq_start,
1270	.next	= input_handlers_seq_next,
1271	.stop	= input_seq_stop,
1272	.show	= input_handlers_seq_show,
1273};
1274
1275static int input_proc_handlers_open(struct inode *inode, struct file *file)
1276{
1277	return seq_open_private(file, &input_handlers_seq_ops,
1278				sizeof(struct input_seq_state));
1279}
1280
1281static const struct proc_ops input_handlers_proc_ops = {
1282	.proc_open	= input_proc_handlers_open,
1283	.proc_read	= seq_read,
1284	.proc_lseek	= seq_lseek,
1285	.proc_release	= seq_release_private,
 
1286};
1287
1288static int __init input_proc_init(void)
1289{
1290	struct proc_dir_entry *entry;
1291
1292	proc_bus_input_dir = proc_mkdir("bus/input", NULL);
1293	if (!proc_bus_input_dir)
1294		return -ENOMEM;
1295
1296	entry = proc_create("devices", 0, proc_bus_input_dir,
1297			    &input_devices_proc_ops);
1298	if (!entry)
1299		goto fail1;
1300
1301	entry = proc_create("handlers", 0, proc_bus_input_dir,
1302			    &input_handlers_proc_ops);
1303	if (!entry)
1304		goto fail2;
1305
1306	return 0;
1307
1308 fail2:	remove_proc_entry("devices", proc_bus_input_dir);
1309 fail1: remove_proc_entry("bus/input", NULL);
1310	return -ENOMEM;
1311}
1312
1313static void input_proc_exit(void)
1314{
1315	remove_proc_entry("devices", proc_bus_input_dir);
1316	remove_proc_entry("handlers", proc_bus_input_dir);
1317	remove_proc_entry("bus/input", NULL);
1318}
1319
1320#else /* !CONFIG_PROC_FS */
1321static inline void input_wakeup_procfs_readers(void) { }
1322static inline int input_proc_init(void) { return 0; }
1323static inline void input_proc_exit(void) { }
1324#endif
1325
1326#define INPUT_DEV_STRING_ATTR_SHOW(name)				\
1327static ssize_t input_dev_show_##name(struct device *dev,		\
1328				     struct device_attribute *attr,	\
1329				     char *buf)				\
1330{									\
1331	struct input_dev *input_dev = to_input_dev(dev);		\
1332									\
1333	return sysfs_emit(buf, "%s\n",					\
1334			  input_dev->name ? input_dev->name : "");	\
1335}									\
1336static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
1337
1338INPUT_DEV_STRING_ATTR_SHOW(name);
1339INPUT_DEV_STRING_ATTR_SHOW(phys);
1340INPUT_DEV_STRING_ATTR_SHOW(uniq);
1341
1342static int input_print_modalias_bits(char *buf, int size,
1343				     char name, const unsigned long *bm,
1344				     unsigned int min_bit, unsigned int max_bit)
1345{
1346	int bit = min_bit;
1347	int len = 0;
1348
1349	len += snprintf(buf, max(size, 0), "%c", name);
1350	for_each_set_bit_from(bit, bm, max_bit)
1351		len += snprintf(buf + len, max(size - len, 0), "%X,", bit);
 
1352	return len;
1353}
1354
1355static int input_print_modalias_parts(char *buf, int size, int full_len,
1356				      const struct input_dev *id)
1357{
1358	int len, klen, remainder, space;
1359
1360	len = snprintf(buf, max(size, 0),
1361		       "input:b%04Xv%04Xp%04Xe%04X-",
1362		       id->id.bustype, id->id.vendor,
1363		       id->id.product, id->id.version);
1364
1365	len += input_print_modalias_bits(buf + len, size - len,
1366				'e', id->evbit, 0, EV_MAX);
1367
1368	/*
1369	 * Calculate the remaining space in the buffer making sure we
1370	 * have place for the terminating 0.
1371	 */
1372	space = max(size - (len + 1), 0);
1373
1374	klen = input_print_modalias_bits(buf + len, size - len,
1375				'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
1376	len += klen;
1377
1378	/*
1379	 * If we have more data than we can fit in the buffer, check
1380	 * if we can trim key data to fit in the rest. We will indicate
1381	 * that key data is incomplete by adding "+" sign at the end, like
1382	 * this: * "k1,2,3,45,+,".
1383	 *
1384	 * Note that we shortest key info (if present) is "k+," so we
1385	 * can only try to trim if key data is longer than that.
1386	 */
1387	if (full_len && size < full_len + 1 && klen > 3) {
1388		remainder = full_len - len;
1389		/*
1390		 * We can only trim if we have space for the remainder
1391		 * and also for at least "k+," which is 3 more characters.
1392		 */
1393		if (remainder <= space - 3) {
1394			/*
1395			 * We are guaranteed to have 'k' in the buffer, so
1396			 * we need at least 3 additional bytes for storing
1397			 * "+," in addition to the remainder.
1398			 */
1399			for (int i = size - 1 - remainder - 3; i >= 0; i--) {
1400				if (buf[i] == 'k' || buf[i] == ',') {
1401					strcpy(buf + i + 1, "+,");
1402					len = i + 3; /* Not counting '\0' */
1403					break;
1404				}
1405			}
1406		}
1407	}
1408
1409	len += input_print_modalias_bits(buf + len, size - len,
1410				'r', id->relbit, 0, REL_MAX);
1411	len += input_print_modalias_bits(buf + len, size - len,
1412				'a', id->absbit, 0, ABS_MAX);
1413	len += input_print_modalias_bits(buf + len, size - len,
1414				'm', id->mscbit, 0, MSC_MAX);
1415	len += input_print_modalias_bits(buf + len, size - len,
1416				'l', id->ledbit, 0, LED_MAX);
1417	len += input_print_modalias_bits(buf + len, size - len,
1418				's', id->sndbit, 0, SND_MAX);
1419	len += input_print_modalias_bits(buf + len, size - len,
1420				'f', id->ffbit, 0, FF_MAX);
1421	len += input_print_modalias_bits(buf + len, size - len,
1422				'w', id->swbit, 0, SW_MAX);
1423
 
 
 
1424	return len;
1425}
1426
1427static int input_print_modalias(char *buf, int size, const struct input_dev *id)
1428{
1429	int full_len;
1430
1431	/*
1432	 * Printing is done in 2 passes: first one figures out total length
1433	 * needed for the modalias string, second one will try to trim key
1434	 * data in case when buffer is too small for the entire modalias.
1435	 * If the buffer is too small regardless, it will fill as much as it
1436	 * can (without trimming key data) into the buffer and leave it to
1437	 * the caller to figure out what to do with the result.
1438	 */
1439	full_len = input_print_modalias_parts(NULL, 0, 0, id);
1440	return input_print_modalias_parts(buf, size, full_len, id);
1441}
1442
1443static ssize_t input_dev_show_modalias(struct device *dev,
1444				       struct device_attribute *attr,
1445				       char *buf)
1446{
1447	struct input_dev *id = to_input_dev(dev);
1448	ssize_t len;
1449
1450	len = input_print_modalias(buf, PAGE_SIZE, id);
1451	if (len < PAGE_SIZE - 2)
1452		len += snprintf(buf + len, PAGE_SIZE - len, "\n");
1453
1454	return min_t(int, len, PAGE_SIZE);
1455}
1456static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
1457
1458static int input_print_bitmap(char *buf, int buf_size, const unsigned long *bitmap,
1459			      int max, int add_cr);
1460
1461static ssize_t input_dev_show_properties(struct device *dev,
1462					 struct device_attribute *attr,
1463					 char *buf)
1464{
1465	struct input_dev *input_dev = to_input_dev(dev);
1466	int len = input_print_bitmap(buf, PAGE_SIZE, input_dev->propbit,
1467				     INPUT_PROP_MAX, true);
1468	return min_t(int, len, PAGE_SIZE);
1469}
1470static DEVICE_ATTR(properties, S_IRUGO, input_dev_show_properties, NULL);
1471
1472static int input_inhibit_device(struct input_dev *dev);
1473static int input_uninhibit_device(struct input_dev *dev);
1474
1475static ssize_t inhibited_show(struct device *dev,
1476			      struct device_attribute *attr,
1477			      char *buf)
1478{
1479	struct input_dev *input_dev = to_input_dev(dev);
1480
1481	return sysfs_emit(buf, "%d\n", input_dev->inhibited);
1482}
1483
1484static ssize_t inhibited_store(struct device *dev,
1485			       struct device_attribute *attr, const char *buf,
1486			       size_t len)
1487{
1488	struct input_dev *input_dev = to_input_dev(dev);
1489	ssize_t rv;
1490	bool inhibited;
1491
1492	if (kstrtobool(buf, &inhibited))
1493		return -EINVAL;
1494
1495	if (inhibited)
1496		rv = input_inhibit_device(input_dev);
1497	else
1498		rv = input_uninhibit_device(input_dev);
1499
1500	if (rv != 0)
1501		return rv;
1502
1503	return len;
1504}
1505
1506static DEVICE_ATTR_RW(inhibited);
1507
1508static struct attribute *input_dev_attrs[] = {
1509	&dev_attr_name.attr,
1510	&dev_attr_phys.attr,
1511	&dev_attr_uniq.attr,
1512	&dev_attr_modalias.attr,
1513	&dev_attr_properties.attr,
1514	&dev_attr_inhibited.attr,
1515	NULL
1516};
1517
1518static const struct attribute_group input_dev_attr_group = {
1519	.attrs	= input_dev_attrs,
1520};
1521
1522#define INPUT_DEV_ID_ATTR(name)						\
1523static ssize_t input_dev_show_id_##name(struct device *dev,		\
1524					struct device_attribute *attr,	\
1525					char *buf)			\
1526{									\
1527	struct input_dev *input_dev = to_input_dev(dev);		\
1528	return sysfs_emit(buf, "%04x\n", input_dev->id.name);		\
1529}									\
1530static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
1531
1532INPUT_DEV_ID_ATTR(bustype);
1533INPUT_DEV_ID_ATTR(vendor);
1534INPUT_DEV_ID_ATTR(product);
1535INPUT_DEV_ID_ATTR(version);
1536
1537static struct attribute *input_dev_id_attrs[] = {
1538	&dev_attr_bustype.attr,
1539	&dev_attr_vendor.attr,
1540	&dev_attr_product.attr,
1541	&dev_attr_version.attr,
1542	NULL
1543};
1544
1545static const struct attribute_group input_dev_id_attr_group = {
1546	.name	= "id",
1547	.attrs	= input_dev_id_attrs,
1548};
1549
1550static int input_print_bitmap(char *buf, int buf_size, const unsigned long *bitmap,
1551			      int max, int add_cr)
1552{
1553	int i;
1554	int len = 0;
1555	bool skip_empty = true;
1556
1557	for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1558		len += input_bits_to_string(buf + len, max(buf_size - len, 0),
1559					    bitmap[i], skip_empty);
1560		if (len) {
1561			skip_empty = false;
1562			if (i > 0)
1563				len += snprintf(buf + len, max(buf_size - len, 0), " ");
1564		}
1565	}
1566
1567	/*
1568	 * If no output was produced print a single 0.
1569	 */
1570	if (len == 0)
1571		len = snprintf(buf, buf_size, "%d", 0);
1572
1573	if (add_cr)
1574		len += snprintf(buf + len, max(buf_size - len, 0), "\n");
1575
1576	return len;
1577}
1578
1579#define INPUT_DEV_CAP_ATTR(ev, bm)					\
1580static ssize_t input_dev_show_cap_##bm(struct device *dev,		\
1581				       struct device_attribute *attr,	\
1582				       char *buf)			\
1583{									\
1584	struct input_dev *input_dev = to_input_dev(dev);		\
1585	int len = input_print_bitmap(buf, PAGE_SIZE,			\
1586				     input_dev->bm##bit, ev##_MAX,	\
1587				     true);				\
1588	return min_t(int, len, PAGE_SIZE);				\
1589}									\
1590static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
1591
1592INPUT_DEV_CAP_ATTR(EV, ev);
1593INPUT_DEV_CAP_ATTR(KEY, key);
1594INPUT_DEV_CAP_ATTR(REL, rel);
1595INPUT_DEV_CAP_ATTR(ABS, abs);
1596INPUT_DEV_CAP_ATTR(MSC, msc);
1597INPUT_DEV_CAP_ATTR(LED, led);
1598INPUT_DEV_CAP_ATTR(SND, snd);
1599INPUT_DEV_CAP_ATTR(FF, ff);
1600INPUT_DEV_CAP_ATTR(SW, sw);
1601
1602static struct attribute *input_dev_caps_attrs[] = {
1603	&dev_attr_ev.attr,
1604	&dev_attr_key.attr,
1605	&dev_attr_rel.attr,
1606	&dev_attr_abs.attr,
1607	&dev_attr_msc.attr,
1608	&dev_attr_led.attr,
1609	&dev_attr_snd.attr,
1610	&dev_attr_ff.attr,
1611	&dev_attr_sw.attr,
1612	NULL
1613};
1614
1615static const struct attribute_group input_dev_caps_attr_group = {
1616	.name	= "capabilities",
1617	.attrs	= input_dev_caps_attrs,
1618};
1619
1620static const struct attribute_group *input_dev_attr_groups[] = {
1621	&input_dev_attr_group,
1622	&input_dev_id_attr_group,
1623	&input_dev_caps_attr_group,
1624	&input_poller_attribute_group,
1625	NULL
1626};
1627
1628static void input_dev_release(struct device *device)
1629{
1630	struct input_dev *dev = to_input_dev(device);
1631
1632	input_ff_destroy(dev);
1633	input_mt_destroy_slots(dev);
1634	kfree(dev->poller);
1635	kfree(dev->absinfo);
1636	kfree(dev->vals);
1637	kfree(dev);
1638
1639	module_put(THIS_MODULE);
1640}
1641
1642/*
1643 * Input uevent interface - loading event handlers based on
1644 * device bitfields.
1645 */
1646static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
1647				   const char *name, const unsigned long *bitmap, int max)
1648{
1649	int len;
1650
1651	if (add_uevent_var(env, "%s", name))
1652		return -ENOMEM;
1653
1654	len = input_print_bitmap(&env->buf[env->buflen - 1],
1655				 sizeof(env->buf) - env->buflen,
1656				 bitmap, max, false);
1657	if (len >= (sizeof(env->buf) - env->buflen))
1658		return -ENOMEM;
1659
1660	env->buflen += len;
1661	return 0;
1662}
1663
1664/*
1665 * This is a pretty gross hack. When building uevent data the driver core
1666 * may try adding more environment variables to kobj_uevent_env without
1667 * telling us, so we have no idea how much of the buffer we can use to
1668 * avoid overflows/-ENOMEM elsewhere. To work around this let's artificially
1669 * reduce amount of memory we will use for the modalias environment variable.
1670 *
1671 * The potential additions are:
1672 *
1673 * SEQNUM=18446744073709551615 - (%llu - 28 bytes)
1674 * HOME=/ (6 bytes)
1675 * PATH=/sbin:/bin:/usr/sbin:/usr/bin (34 bytes)
1676 *
1677 * 68 bytes total. Allow extra buffer - 96 bytes
1678 */
1679#define UEVENT_ENV_EXTRA_LEN	96
1680
1681static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
1682					 const struct input_dev *dev)
1683{
1684	int len;
1685
1686	if (add_uevent_var(env, "MODALIAS="))
1687		return -ENOMEM;
1688
1689	len = input_print_modalias(&env->buf[env->buflen - 1],
1690				   (int)sizeof(env->buf) - env->buflen -
1691					UEVENT_ENV_EXTRA_LEN,
1692				   dev);
1693	if (len >= ((int)sizeof(env->buf) - env->buflen -
1694					UEVENT_ENV_EXTRA_LEN))
1695		return -ENOMEM;
1696
1697	env->buflen += len;
1698	return 0;
1699}
1700
1701#define INPUT_ADD_HOTPLUG_VAR(fmt, val...)				\
1702	do {								\
1703		int err = add_uevent_var(env, fmt, val);		\
1704		if (err)						\
1705			return err;					\
1706	} while (0)
1707
1708#define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max)				\
1709	do {								\
1710		int err = input_add_uevent_bm_var(env, name, bm, max);	\
1711		if (err)						\
1712			return err;					\
1713	} while (0)
1714
1715#define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev)				\
1716	do {								\
1717		int err = input_add_uevent_modalias_var(env, dev);	\
1718		if (err)						\
1719			return err;					\
1720	} while (0)
1721
1722static int input_dev_uevent(const struct device *device, struct kobj_uevent_env *env)
1723{
1724	const struct input_dev *dev = to_input_dev(device);
1725
1726	INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
1727				dev->id.bustype, dev->id.vendor,
1728				dev->id.product, dev->id.version);
1729	if (dev->name)
1730		INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
1731	if (dev->phys)
1732		INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
1733	if (dev->uniq)
1734		INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
1735
1736	INPUT_ADD_HOTPLUG_BM_VAR("PROP=", dev->propbit, INPUT_PROP_MAX);
1737
1738	INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
1739	if (test_bit(EV_KEY, dev->evbit))
1740		INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
1741	if (test_bit(EV_REL, dev->evbit))
1742		INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
1743	if (test_bit(EV_ABS, dev->evbit))
1744		INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
1745	if (test_bit(EV_MSC, dev->evbit))
1746		INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
1747	if (test_bit(EV_LED, dev->evbit))
1748		INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
1749	if (test_bit(EV_SND, dev->evbit))
1750		INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
1751	if (test_bit(EV_FF, dev->evbit))
1752		INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
1753	if (test_bit(EV_SW, dev->evbit))
1754		INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
1755
1756	INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
1757
1758	return 0;
1759}
1760
1761#define INPUT_DO_TOGGLE(dev, type, bits, on)				\
1762	do {								\
1763		int i;							\
1764		bool active;						\
1765									\
1766		if (!test_bit(EV_##type, dev->evbit))			\
1767			break;						\
1768									\
1769		for_each_set_bit(i, dev->bits##bit, type##_CNT) {	\
1770			active = test_bit(i, dev->bits);		\
1771			if (!active && !on)				\
1772				continue;				\
1773									\
1774			dev->event(dev, EV_##type, i, on ? active : 0);	\
1775		}							\
1776	} while (0)
1777
1778static void input_dev_toggle(struct input_dev *dev, bool activate)
1779{
1780	if (!dev->event)
1781		return;
1782
1783	INPUT_DO_TOGGLE(dev, LED, led, activate);
1784	INPUT_DO_TOGGLE(dev, SND, snd, activate);
1785
1786	if (activate && test_bit(EV_REP, dev->evbit)) {
1787		dev->event(dev, EV_REP, REP_PERIOD, dev->rep[REP_PERIOD]);
1788		dev->event(dev, EV_REP, REP_DELAY, dev->rep[REP_DELAY]);
1789	}
1790}
1791
1792/**
1793 * input_reset_device() - reset/restore the state of input device
1794 * @dev: input device whose state needs to be reset
1795 *
1796 * This function tries to reset the state of an opened input device and
1797 * bring internal state and state if the hardware in sync with each other.
1798 * We mark all keys as released, restore LED state, repeat rate, etc.
1799 */
1800void input_reset_device(struct input_dev *dev)
1801{
1802	unsigned long flags;
1803
1804	mutex_lock(&dev->mutex);
1805	spin_lock_irqsave(&dev->event_lock, flags);
1806
1807	input_dev_toggle(dev, true);
1808	if (input_dev_release_keys(dev))
1809		input_handle_event(dev, EV_SYN, SYN_REPORT, 1);
1810
1811	spin_unlock_irqrestore(&dev->event_lock, flags);
1812	mutex_unlock(&dev->mutex);
1813}
1814EXPORT_SYMBOL(input_reset_device);
1815
1816static int input_inhibit_device(struct input_dev *dev)
1817{
1818	mutex_lock(&dev->mutex);
1819
1820	if (dev->inhibited)
1821		goto out;
1822
1823	if (dev->users) {
1824		if (dev->close)
1825			dev->close(dev);
1826		if (dev->poller)
1827			input_dev_poller_stop(dev->poller);
1828	}
1829
1830	spin_lock_irq(&dev->event_lock);
1831	input_mt_release_slots(dev);
1832	input_dev_release_keys(dev);
1833	input_handle_event(dev, EV_SYN, SYN_REPORT, 1);
1834	input_dev_toggle(dev, false);
1835	spin_unlock_irq(&dev->event_lock);
1836
1837	dev->inhibited = true;
1838
1839out:
1840	mutex_unlock(&dev->mutex);
1841	return 0;
1842}
1843
1844static int input_uninhibit_device(struct input_dev *dev)
1845{
1846	int ret = 0;
1847
1848	mutex_lock(&dev->mutex);
1849
1850	if (!dev->inhibited)
1851		goto out;
1852
1853	if (dev->users) {
1854		if (dev->open) {
1855			ret = dev->open(dev);
1856			if (ret)
1857				goto out;
1858		}
1859		if (dev->poller)
1860			input_dev_poller_start(dev->poller);
1861	}
1862
1863	dev->inhibited = false;
1864	spin_lock_irq(&dev->event_lock);
1865	input_dev_toggle(dev, true);
1866	spin_unlock_irq(&dev->event_lock);
1867
1868out:
1869	mutex_unlock(&dev->mutex);
1870	return ret;
1871}
1872
1873static int input_dev_suspend(struct device *dev)
1874{
1875	struct input_dev *input_dev = to_input_dev(dev);
1876
1877	spin_lock_irq(&input_dev->event_lock);
1878
1879	/*
1880	 * Keys that are pressed now are unlikely to be
1881	 * still pressed when we resume.
1882	 */
1883	if (input_dev_release_keys(input_dev))
1884		input_handle_event(input_dev, EV_SYN, SYN_REPORT, 1);
1885
1886	/* Turn off LEDs and sounds, if any are active. */
1887	input_dev_toggle(input_dev, false);
1888
1889	spin_unlock_irq(&input_dev->event_lock);
1890
1891	return 0;
1892}
1893
1894static int input_dev_resume(struct device *dev)
1895{
1896	struct input_dev *input_dev = to_input_dev(dev);
1897
1898	spin_lock_irq(&input_dev->event_lock);
1899
1900	/* Restore state of LEDs and sounds, if any were active. */
1901	input_dev_toggle(input_dev, true);
1902
1903	spin_unlock_irq(&input_dev->event_lock);
1904
1905	return 0;
1906}
1907
1908static int input_dev_freeze(struct device *dev)
1909{
1910	struct input_dev *input_dev = to_input_dev(dev);
1911
1912	spin_lock_irq(&input_dev->event_lock);
1913
1914	/*
1915	 * Keys that are pressed now are unlikely to be
1916	 * still pressed when we resume.
1917	 */
1918	if (input_dev_release_keys(input_dev))
1919		input_handle_event(input_dev, EV_SYN, SYN_REPORT, 1);
1920
1921	spin_unlock_irq(&input_dev->event_lock);
1922
1923	return 0;
1924}
1925
1926static int input_dev_poweroff(struct device *dev)
1927{
1928	struct input_dev *input_dev = to_input_dev(dev);
1929
1930	spin_lock_irq(&input_dev->event_lock);
1931
1932	/* Turn off LEDs and sounds, if any are active. */
1933	input_dev_toggle(input_dev, false);
1934
1935	spin_unlock_irq(&input_dev->event_lock);
1936
1937	return 0;
1938}
1939
1940static const struct dev_pm_ops input_dev_pm_ops = {
1941	.suspend	= input_dev_suspend,
1942	.resume		= input_dev_resume,
1943	.freeze		= input_dev_freeze,
1944	.poweroff	= input_dev_poweroff,
1945	.restore	= input_dev_resume,
1946};
 
1947
1948static const struct device_type input_dev_type = {
1949	.groups		= input_dev_attr_groups,
1950	.release	= input_dev_release,
1951	.uevent		= input_dev_uevent,
1952	.pm		= pm_sleep_ptr(&input_dev_pm_ops),
 
 
1953};
1954
1955static char *input_devnode(const struct device *dev, umode_t *mode)
1956{
1957	return kasprintf(GFP_KERNEL, "input/%s", dev_name(dev));
1958}
1959
1960const struct class input_class = {
1961	.name		= "input",
1962	.devnode	= input_devnode,
1963};
1964EXPORT_SYMBOL_GPL(input_class);
1965
1966/**
1967 * input_allocate_device - allocate memory for new input device
1968 *
1969 * Returns prepared struct input_dev or %NULL.
1970 *
1971 * NOTE: Use input_free_device() to free devices that have not been
1972 * registered; input_unregister_device() should be used for already
1973 * registered devices.
1974 */
1975struct input_dev *input_allocate_device(void)
1976{
1977	static atomic_t input_no = ATOMIC_INIT(-1);
1978	struct input_dev *dev;
1979
1980	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1981	if (!dev)
1982		return NULL;
 
 
 
 
 
 
 
 
 
 
1983
1984	/*
1985	 * Start with space for SYN_REPORT + 7 EV_KEY/EV_MSC events + 2 spare,
1986	 * see input_estimate_events_per_packet(). We will tune the number
1987	 * when we register the device.
1988	 */
1989	dev->max_vals = 10;
1990	dev->vals = kcalloc(dev->max_vals, sizeof(*dev->vals), GFP_KERNEL);
1991	if (!dev->vals) {
1992		kfree(dev);
1993		return NULL;
1994	}
1995
1996	mutex_init(&dev->mutex);
1997	spin_lock_init(&dev->event_lock);
1998	timer_setup(&dev->timer, NULL, 0);
1999	INIT_LIST_HEAD(&dev->h_list);
2000	INIT_LIST_HEAD(&dev->node);
2001
2002	dev->dev.type = &input_dev_type;
2003	dev->dev.class = &input_class;
2004	device_initialize(&dev->dev);
2005	/*
2006	 * From this point on we can no longer simply "kfree(dev)", we need
2007	 * to use input_free_device() so that device core properly frees its
2008	 * resources associated with the input device.
2009	 */
2010
2011	dev_set_name(&dev->dev, "input%lu",
2012		     (unsigned long)atomic_inc_return(&input_no));
2013
2014	__module_get(THIS_MODULE);
2015
2016	return dev;
2017}
2018EXPORT_SYMBOL(input_allocate_device);
2019
2020struct input_devres {
2021	struct input_dev *input;
2022};
2023
2024static int devm_input_device_match(struct device *dev, void *res, void *data)
2025{
2026	struct input_devres *devres = res;
2027
2028	return devres->input == data;
2029}
2030
2031static void devm_input_device_release(struct device *dev, void *res)
2032{
2033	struct input_devres *devres = res;
2034	struct input_dev *input = devres->input;
2035
2036	dev_dbg(dev, "%s: dropping reference to %s\n",
2037		__func__, dev_name(&input->dev));
2038	input_put_device(input);
2039}
2040
2041/**
2042 * devm_input_allocate_device - allocate managed input device
2043 * @dev: device owning the input device being created
2044 *
2045 * Returns prepared struct input_dev or %NULL.
2046 *
2047 * Managed input devices do not need to be explicitly unregistered or
2048 * freed as it will be done automatically when owner device unbinds from
2049 * its driver (or binding fails). Once managed input device is allocated,
2050 * it is ready to be set up and registered in the same fashion as regular
2051 * input device. There are no special devm_input_device_[un]register()
2052 * variants, regular ones work with both managed and unmanaged devices,
2053 * should you need them. In most cases however, managed input device need
2054 * not be explicitly unregistered or freed.
2055 *
2056 * NOTE: the owner device is set up as parent of input device and users
2057 * should not override it.
2058 */
2059struct input_dev *devm_input_allocate_device(struct device *dev)
2060{
2061	struct input_dev *input;
2062	struct input_devres *devres;
2063
2064	devres = devres_alloc(devm_input_device_release,
2065			      sizeof(*devres), GFP_KERNEL);
2066	if (!devres)
2067		return NULL;
2068
2069	input = input_allocate_device();
2070	if (!input) {
2071		devres_free(devres);
2072		return NULL;
2073	}
2074
2075	input->dev.parent = dev;
2076	input->devres_managed = true;
2077
2078	devres->input = input;
2079	devres_add(dev, devres);
2080
2081	return input;
2082}
2083EXPORT_SYMBOL(devm_input_allocate_device);
2084
2085/**
2086 * input_free_device - free memory occupied by input_dev structure
2087 * @dev: input device to free
2088 *
2089 * This function should only be used if input_register_device()
2090 * was not called yet or if it failed. Once device was registered
2091 * use input_unregister_device() and memory will be freed once last
2092 * reference to the device is dropped.
2093 *
2094 * Device should be allocated by input_allocate_device().
2095 *
2096 * NOTE: If there are references to the input device then memory
2097 * will not be freed until last reference is dropped.
2098 */
2099void input_free_device(struct input_dev *dev)
2100{
2101	if (dev) {
2102		if (dev->devres_managed)
2103			WARN_ON(devres_destroy(dev->dev.parent,
2104						devm_input_device_release,
2105						devm_input_device_match,
2106						dev));
2107		input_put_device(dev);
2108	}
2109}
2110EXPORT_SYMBOL(input_free_device);
2111
2112/**
2113 * input_set_timestamp - set timestamp for input events
2114 * @dev: input device to set timestamp for
2115 * @timestamp: the time at which the event has occurred
2116 *   in CLOCK_MONOTONIC
2117 *
2118 * This function is intended to provide to the input system a more
2119 * accurate time of when an event actually occurred. The driver should
2120 * call this function as soon as a timestamp is acquired ensuring
2121 * clock conversions in input_set_timestamp are done correctly.
2122 *
2123 * The system entering suspend state between timestamp acquisition and
2124 * calling input_set_timestamp can result in inaccurate conversions.
2125 */
2126void input_set_timestamp(struct input_dev *dev, ktime_t timestamp)
2127{
2128	dev->timestamp[INPUT_CLK_MONO] = timestamp;
2129	dev->timestamp[INPUT_CLK_REAL] = ktime_mono_to_real(timestamp);
2130	dev->timestamp[INPUT_CLK_BOOT] = ktime_mono_to_any(timestamp,
2131							   TK_OFFS_BOOT);
2132}
2133EXPORT_SYMBOL(input_set_timestamp);
2134
2135/**
2136 * input_get_timestamp - get timestamp for input events
2137 * @dev: input device to get timestamp from
2138 *
2139 * A valid timestamp is a timestamp of non-zero value.
2140 */
2141ktime_t *input_get_timestamp(struct input_dev *dev)
2142{
2143	const ktime_t invalid_timestamp = ktime_set(0, 0);
2144
2145	if (!ktime_compare(dev->timestamp[INPUT_CLK_MONO], invalid_timestamp))
2146		input_set_timestamp(dev, ktime_get());
2147
2148	return dev->timestamp;
2149}
2150EXPORT_SYMBOL(input_get_timestamp);
2151
2152/**
2153 * input_set_capability - mark device as capable of a certain event
2154 * @dev: device that is capable of emitting or accepting event
2155 * @type: type of the event (EV_KEY, EV_REL, etc...)
2156 * @code: event code
2157 *
2158 * In addition to setting up corresponding bit in appropriate capability
2159 * bitmap the function also adjusts dev->evbit.
2160 */
2161void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
2162{
2163	if (type < EV_CNT && input_max_code[type] &&
2164	    code > input_max_code[type]) {
2165		pr_err("%s: invalid code %u for type %u\n", __func__, code,
2166		       type);
2167		dump_stack();
2168		return;
2169	}
2170
2171	switch (type) {
2172	case EV_KEY:
2173		__set_bit(code, dev->keybit);
2174		break;
2175
2176	case EV_REL:
2177		__set_bit(code, dev->relbit);
2178		break;
2179
2180	case EV_ABS:
2181		input_alloc_absinfo(dev);
 
 
 
2182		__set_bit(code, dev->absbit);
2183		break;
2184
2185	case EV_MSC:
2186		__set_bit(code, dev->mscbit);
2187		break;
2188
2189	case EV_SW:
2190		__set_bit(code, dev->swbit);
2191		break;
2192
2193	case EV_LED:
2194		__set_bit(code, dev->ledbit);
2195		break;
2196
2197	case EV_SND:
2198		__set_bit(code, dev->sndbit);
2199		break;
2200
2201	case EV_FF:
2202		__set_bit(code, dev->ffbit);
2203		break;
2204
2205	case EV_PWR:
2206		/* do nothing */
2207		break;
2208
2209	default:
2210		pr_err("%s: unknown type %u (code %u)\n", __func__, type, code);
 
2211		dump_stack();
2212		return;
2213	}
2214
2215	__set_bit(type, dev->evbit);
2216}
2217EXPORT_SYMBOL(input_set_capability);
2218
2219static unsigned int input_estimate_events_per_packet(struct input_dev *dev)
2220{
2221	int mt_slots;
2222	int i;
2223	unsigned int events;
2224
2225	if (dev->mt) {
2226		mt_slots = dev->mt->num_slots;
2227	} else if (test_bit(ABS_MT_TRACKING_ID, dev->absbit)) {
2228		mt_slots = dev->absinfo[ABS_MT_TRACKING_ID].maximum -
2229			   dev->absinfo[ABS_MT_TRACKING_ID].minimum + 1;
2230		mt_slots = clamp(mt_slots, 2, 32);
2231	} else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
2232		mt_slots = 2;
2233	} else {
2234		mt_slots = 0;
2235	}
2236
2237	events = mt_slots + 1; /* count SYN_MT_REPORT and SYN_REPORT */
2238
2239	if (test_bit(EV_ABS, dev->evbit))
2240		for_each_set_bit(i, dev->absbit, ABS_CNT)
2241			events += input_is_mt_axis(i) ? mt_slots : 1;
2242
2243	if (test_bit(EV_REL, dev->evbit))
2244		events += bitmap_weight(dev->relbit, REL_CNT);
2245
2246	/* Make room for KEY and MSC events */
2247	events += 7;
2248
2249	return events;
2250}
2251
2252#define INPUT_CLEANSE_BITMASK(dev, type, bits)				\
2253	do {								\
2254		if (!test_bit(EV_##type, dev->evbit))			\
2255			memset(dev->bits##bit, 0,			\
2256				sizeof(dev->bits##bit));		\
2257	} while (0)
2258
2259static void input_cleanse_bitmasks(struct input_dev *dev)
2260{
2261	INPUT_CLEANSE_BITMASK(dev, KEY, key);
2262	INPUT_CLEANSE_BITMASK(dev, REL, rel);
2263	INPUT_CLEANSE_BITMASK(dev, ABS, abs);
2264	INPUT_CLEANSE_BITMASK(dev, MSC, msc);
2265	INPUT_CLEANSE_BITMASK(dev, LED, led);
2266	INPUT_CLEANSE_BITMASK(dev, SND, snd);
2267	INPUT_CLEANSE_BITMASK(dev, FF, ff);
2268	INPUT_CLEANSE_BITMASK(dev, SW, sw);
2269}
2270
2271static void __input_unregister_device(struct input_dev *dev)
2272{
2273	struct input_handle *handle, *next;
2274
2275	input_disconnect_device(dev);
2276
2277	mutex_lock(&input_mutex);
2278
2279	list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
2280		handle->handler->disconnect(handle);
2281	WARN_ON(!list_empty(&dev->h_list));
2282
2283	del_timer_sync(&dev->timer);
2284	list_del_init(&dev->node);
2285
2286	input_wakeup_procfs_readers();
2287
2288	mutex_unlock(&input_mutex);
2289
2290	device_del(&dev->dev);
2291}
2292
2293static void devm_input_device_unregister(struct device *dev, void *res)
2294{
2295	struct input_devres *devres = res;
2296	struct input_dev *input = devres->input;
2297
2298	dev_dbg(dev, "%s: unregistering device %s\n",
2299		__func__, dev_name(&input->dev));
2300	__input_unregister_device(input);
2301}
2302
2303/*
2304 * Generate software autorepeat event. Note that we take
2305 * dev->event_lock here to avoid racing with input_event
2306 * which may cause keys get "stuck".
2307 */
2308static void input_repeat_key(struct timer_list *t)
2309{
2310	struct input_dev *dev = from_timer(dev, t, timer);
2311	unsigned long flags;
2312
2313	spin_lock_irqsave(&dev->event_lock, flags);
2314
2315	if (!dev->inhibited &&
2316	    test_bit(dev->repeat_key, dev->key) &&
2317	    is_event_supported(dev->repeat_key, dev->keybit, KEY_MAX)) {
2318
2319		input_set_timestamp(dev, ktime_get());
2320		input_handle_event(dev, EV_KEY, dev->repeat_key, 2);
2321		input_handle_event(dev, EV_SYN, SYN_REPORT, 1);
2322
2323		if (dev->rep[REP_PERIOD])
2324			mod_timer(&dev->timer, jiffies +
2325					msecs_to_jiffies(dev->rep[REP_PERIOD]));
2326	}
2327
2328	spin_unlock_irqrestore(&dev->event_lock, flags);
2329}
2330
2331/**
2332 * input_enable_softrepeat - enable software autorepeat
2333 * @dev: input device
2334 * @delay: repeat delay
2335 * @period: repeat period
2336 *
2337 * Enable software autorepeat on the input device.
2338 */
2339void input_enable_softrepeat(struct input_dev *dev, int delay, int period)
2340{
 
2341	dev->timer.function = input_repeat_key;
2342	dev->rep[REP_DELAY] = delay;
2343	dev->rep[REP_PERIOD] = period;
2344}
2345EXPORT_SYMBOL(input_enable_softrepeat);
2346
2347bool input_device_enabled(struct input_dev *dev)
2348{
2349	lockdep_assert_held(&dev->mutex);
2350
2351	return !dev->inhibited && dev->users > 0;
2352}
2353EXPORT_SYMBOL_GPL(input_device_enabled);
2354
2355static int input_device_tune_vals(struct input_dev *dev)
2356{
2357	struct input_value *vals;
2358	unsigned int packet_size;
2359	unsigned int max_vals;
2360
2361	packet_size = input_estimate_events_per_packet(dev);
2362	if (dev->hint_events_per_packet < packet_size)
2363		dev->hint_events_per_packet = packet_size;
2364
2365	max_vals = dev->hint_events_per_packet + 2;
2366	if (dev->max_vals >= max_vals)
2367		return 0;
2368
2369	vals = kcalloc(max_vals, sizeof(*vals), GFP_KERNEL);
2370	if (!vals)
2371		return -ENOMEM;
2372
2373	spin_lock_irq(&dev->event_lock);
2374	dev->max_vals = max_vals;
2375	swap(dev->vals, vals);
2376	spin_unlock_irq(&dev->event_lock);
2377
2378	/* Because of swap() above, this frees the old vals memory */
2379	kfree(vals);
2380
2381	return 0;
2382}
2383
2384/**
2385 * input_register_device - register device with input core
2386 * @dev: device to be registered
2387 *
2388 * This function registers device with input core. The device must be
2389 * allocated with input_allocate_device() and all it's capabilities
2390 * set up before registering.
2391 * If function fails the device must be freed with input_free_device().
2392 * Once device has been successfully registered it can be unregistered
2393 * with input_unregister_device(); input_free_device() should not be
2394 * called in this case.
2395 *
2396 * Note that this function is also used to register managed input devices
2397 * (ones allocated with devm_input_allocate_device()). Such managed input
2398 * devices need not be explicitly unregistered or freed, their tear down
2399 * is controlled by the devres infrastructure. It is also worth noting
2400 * that tear down of managed input devices is internally a 2-step process:
2401 * registered managed input device is first unregistered, but stays in
2402 * memory and can still handle input_event() calls (although events will
2403 * not be delivered anywhere). The freeing of managed input device will
2404 * happen later, when devres stack is unwound to the point where device
2405 * allocation was made.
2406 */
2407int input_register_device(struct input_dev *dev)
2408{
2409	struct input_devres *devres = NULL;
2410	struct input_handler *handler;
 
2411	const char *path;
2412	int error;
2413
2414	if (test_bit(EV_ABS, dev->evbit) && !dev->absinfo) {
2415		dev_err(&dev->dev,
2416			"Absolute device without dev->absinfo, refusing to register\n");
2417		return -EINVAL;
2418	}
2419
2420	if (dev->devres_managed) {
2421		devres = devres_alloc(devm_input_device_unregister,
2422				      sizeof(*devres), GFP_KERNEL);
2423		if (!devres)
2424			return -ENOMEM;
2425
2426		devres->input = dev;
2427	}
2428
2429	/* Every input device generates EV_SYN/SYN_REPORT events. */
2430	__set_bit(EV_SYN, dev->evbit);
2431
2432	/* KEY_RESERVED is not supposed to be transmitted to userspace. */
2433	__clear_bit(KEY_RESERVED, dev->keybit);
2434
2435	/* Make sure that bitmasks not mentioned in dev->evbit are clean. */
2436	input_cleanse_bitmasks(dev);
2437
2438	error = input_device_tune_vals(dev);
2439	if (error)
 
 
 
 
 
 
2440		goto err_devres_free;
 
2441
2442	/*
2443	 * If delay and period are pre-set by the driver, then autorepeating
2444	 * is handled by the driver itself and we don't do it in input.c.
2445	 */
2446	if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD])
2447		input_enable_softrepeat(dev, 250, 33);
2448
2449	if (!dev->getkeycode)
2450		dev->getkeycode = input_default_getkeycode;
2451
2452	if (!dev->setkeycode)
2453		dev->setkeycode = input_default_setkeycode;
2454
2455	if (dev->poller)
2456		input_dev_poller_finalize(dev->poller);
2457
2458	error = device_add(&dev->dev);
2459	if (error)
2460		goto err_devres_free;
2461
2462	path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
2463	pr_info("%s as %s\n",
2464		dev->name ? dev->name : "Unspecified device",
2465		path ? path : "N/A");
2466	kfree(path);
2467
2468	error = mutex_lock_interruptible(&input_mutex);
2469	if (error)
2470		goto err_device_del;
2471
2472	list_add_tail(&dev->node, &input_dev_list);
2473
2474	list_for_each_entry(handler, &input_handler_list, node)
2475		input_attach_handler(dev, handler);
2476
2477	input_wakeup_procfs_readers();
2478
2479	mutex_unlock(&input_mutex);
2480
2481	if (dev->devres_managed) {
2482		dev_dbg(dev->dev.parent, "%s: registering %s with devres.\n",
2483			__func__, dev_name(&dev->dev));
2484		devres_add(dev->dev.parent, devres);
2485	}
2486	return 0;
2487
2488err_device_del:
2489	device_del(&dev->dev);
 
 
 
2490err_devres_free:
2491	devres_free(devres);
2492	return error;
2493}
2494EXPORT_SYMBOL(input_register_device);
2495
2496/**
2497 * input_unregister_device - unregister previously registered device
2498 * @dev: device to be unregistered
2499 *
2500 * This function unregisters an input device. Once device is unregistered
2501 * the caller should not try to access it as it may get freed at any moment.
2502 */
2503void input_unregister_device(struct input_dev *dev)
2504{
2505	if (dev->devres_managed) {
2506		WARN_ON(devres_destroy(dev->dev.parent,
2507					devm_input_device_unregister,
2508					devm_input_device_match,
2509					dev));
2510		__input_unregister_device(dev);
2511		/*
2512		 * We do not do input_put_device() here because it will be done
2513		 * when 2nd devres fires up.
2514		 */
2515	} else {
2516		__input_unregister_device(dev);
2517		input_put_device(dev);
2518	}
2519}
2520EXPORT_SYMBOL(input_unregister_device);
2521
2522static int input_handler_check_methods(const struct input_handler *handler)
2523{
2524	int count = 0;
2525
2526	if (handler->filter)
2527		count++;
2528	if (handler->events)
2529		count++;
2530	if (handler->event)
2531		count++;
2532
2533	if (count > 1) {
2534		pr_err("%s: only one event processing method can be defined (%s)\n",
2535		       __func__, handler->name);
2536		return -EINVAL;
2537	}
2538
2539	return 0;
2540}
2541
2542/**
2543 * input_register_handler - register a new input handler
2544 * @handler: handler to be registered
2545 *
2546 * This function registers a new input handler (interface) for input
2547 * devices in the system and attaches it to all input devices that
2548 * are compatible with the handler.
2549 */
2550int input_register_handler(struct input_handler *handler)
2551{
2552	struct input_dev *dev;
2553	int error;
2554
2555	error = input_handler_check_methods(handler);
2556	if (error)
2557		return error;
2558
2559	INIT_LIST_HEAD(&handler->h_list);
2560
2561	error = mutex_lock_interruptible(&input_mutex);
2562	if (error)
2563		return error;
2564
2565	list_add_tail(&handler->node, &input_handler_list);
2566
2567	list_for_each_entry(dev, &input_dev_list, node)
2568		input_attach_handler(dev, handler);
2569
2570	input_wakeup_procfs_readers();
2571
2572	mutex_unlock(&input_mutex);
2573	return 0;
2574}
2575EXPORT_SYMBOL(input_register_handler);
2576
2577/**
2578 * input_unregister_handler - unregisters an input handler
2579 * @handler: handler to be unregistered
2580 *
2581 * This function disconnects a handler from its input devices and
2582 * removes it from lists of known handlers.
2583 */
2584void input_unregister_handler(struct input_handler *handler)
2585{
2586	struct input_handle *handle, *next;
2587
2588	mutex_lock(&input_mutex);
2589
2590	list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
2591		handler->disconnect(handle);
2592	WARN_ON(!list_empty(&handler->h_list));
2593
2594	list_del_init(&handler->node);
2595
2596	input_wakeup_procfs_readers();
2597
2598	mutex_unlock(&input_mutex);
2599}
2600EXPORT_SYMBOL(input_unregister_handler);
2601
2602/**
2603 * input_handler_for_each_handle - handle iterator
2604 * @handler: input handler to iterate
2605 * @data: data for the callback
2606 * @fn: function to be called for each handle
2607 *
2608 * Iterate over @bus's list of devices, and call @fn for each, passing
2609 * it @data and stop when @fn returns a non-zero value. The function is
2610 * using RCU to traverse the list and therefore may be using in atomic
2611 * contexts. The @fn callback is invoked from RCU critical section and
2612 * thus must not sleep.
2613 */
2614int input_handler_for_each_handle(struct input_handler *handler, void *data,
2615				  int (*fn)(struct input_handle *, void *))
2616{
2617	struct input_handle *handle;
2618	int retval = 0;
2619
2620	rcu_read_lock();
2621
2622	list_for_each_entry_rcu(handle, &handler->h_list, h_node) {
2623		retval = fn(handle, data);
2624		if (retval)
2625			break;
2626	}
2627
2628	rcu_read_unlock();
2629
2630	return retval;
2631}
2632EXPORT_SYMBOL(input_handler_for_each_handle);
2633
2634/*
2635 * An implementation of input_handle's handle_events() method that simply
2636 * invokes handler->event() method for each event one by one.
2637 */
2638static unsigned int input_handle_events_default(struct input_handle *handle,
2639						struct input_value *vals,
2640						unsigned int count)
2641{
2642	struct input_handler *handler = handle->handler;
2643	struct input_value *v;
2644
2645	for (v = vals; v != vals + count; v++)
2646		handler->event(handle, v->type, v->code, v->value);
2647
2648	return count;
2649}
2650
2651/*
2652 * An implementation of input_handle's handle_events() method that invokes
2653 * handler->filter() method for each event one by one and removes events
2654 * that were filtered out from the "vals" array.
2655 */
2656static unsigned int input_handle_events_filter(struct input_handle *handle,
2657					       struct input_value *vals,
2658					       unsigned int count)
2659{
2660	struct input_handler *handler = handle->handler;
2661	struct input_value *end = vals;
2662	struct input_value *v;
2663
2664	for (v = vals; v != vals + count; v++) {
2665		if (handler->filter(handle, v->type, v->code, v->value))
2666			continue;
2667		if (end != v)
2668			*end = *v;
2669		end++;
2670	}
2671
2672	return end - vals;
2673}
2674
2675/*
2676 * An implementation of input_handle's handle_events() method that does nothing.
2677 */
2678static unsigned int input_handle_events_null(struct input_handle *handle,
2679					     struct input_value *vals,
2680					     unsigned int count)
2681{
2682	return count;
2683}
2684
2685/*
2686 * Sets up appropriate handle->event_handler based on the input_handler
2687 * associated with the handle.
2688 */
2689static void input_handle_setup_event_handler(struct input_handle *handle)
2690{
2691	struct input_handler *handler = handle->handler;
2692
2693	if (handler->filter)
2694		handle->handle_events = input_handle_events_filter;
2695	else if (handler->event)
2696		handle->handle_events = input_handle_events_default;
2697	else if (handler->events)
2698		handle->handle_events = handler->events;
2699	else
2700		handle->handle_events = input_handle_events_null;
2701}
2702
2703/**
2704 * input_register_handle - register a new input handle
2705 * @handle: handle to register
2706 *
2707 * This function puts a new input handle onto device's
2708 * and handler's lists so that events can flow through
2709 * it once it is opened using input_open_device().
2710 *
2711 * This function is supposed to be called from handler's
2712 * connect() method.
2713 */
2714int input_register_handle(struct input_handle *handle)
2715{
2716	struct input_handler *handler = handle->handler;
2717	struct input_dev *dev = handle->dev;
2718	int error;
2719
2720	input_handle_setup_event_handler(handle);
2721	/*
2722	 * We take dev->mutex here to prevent race with
2723	 * input_release_device().
2724	 */
2725	error = mutex_lock_interruptible(&dev->mutex);
2726	if (error)
2727		return error;
2728
2729	/*
2730	 * Filters go to the head of the list, normal handlers
2731	 * to the tail.
2732	 */
2733	if (handler->filter)
2734		list_add_rcu(&handle->d_node, &dev->h_list);
2735	else
2736		list_add_tail_rcu(&handle->d_node, &dev->h_list);
2737
2738	mutex_unlock(&dev->mutex);
2739
2740	/*
2741	 * Since we are supposed to be called from ->connect()
2742	 * which is mutually exclusive with ->disconnect()
2743	 * we can't be racing with input_unregister_handle()
2744	 * and so separate lock is not needed here.
2745	 */
2746	list_add_tail_rcu(&handle->h_node, &handler->h_list);
2747
2748	if (handler->start)
2749		handler->start(handle);
2750
2751	return 0;
2752}
2753EXPORT_SYMBOL(input_register_handle);
2754
2755/**
2756 * input_unregister_handle - unregister an input handle
2757 * @handle: handle to unregister
2758 *
2759 * This function removes input handle from device's
2760 * and handler's lists.
2761 *
2762 * This function is supposed to be called from handler's
2763 * disconnect() method.
2764 */
2765void input_unregister_handle(struct input_handle *handle)
2766{
2767	struct input_dev *dev = handle->dev;
2768
2769	list_del_rcu(&handle->h_node);
2770
2771	/*
2772	 * Take dev->mutex to prevent race with input_release_device().
2773	 */
2774	mutex_lock(&dev->mutex);
2775	list_del_rcu(&handle->d_node);
2776	mutex_unlock(&dev->mutex);
2777
2778	synchronize_rcu();
2779}
2780EXPORT_SYMBOL(input_unregister_handle);
2781
2782/**
2783 * input_get_new_minor - allocates a new input minor number
2784 * @legacy_base: beginning or the legacy range to be searched
2785 * @legacy_num: size of legacy range
2786 * @allow_dynamic: whether we can also take ID from the dynamic range
2787 *
2788 * This function allocates a new device minor for from input major namespace.
2789 * Caller can request legacy minor by specifying @legacy_base and @legacy_num
2790 * parameters and whether ID can be allocated from dynamic range if there are
2791 * no free IDs in legacy range.
2792 */
2793int input_get_new_minor(int legacy_base, unsigned int legacy_num,
2794			bool allow_dynamic)
2795{
2796	/*
2797	 * This function should be called from input handler's ->connect()
2798	 * methods, which are serialized with input_mutex, so no additional
2799	 * locking is needed here.
2800	 */
2801	if (legacy_base >= 0) {
2802		int minor = ida_alloc_range(&input_ida, legacy_base,
2803					    legacy_base + legacy_num - 1,
2804					    GFP_KERNEL);
 
2805		if (minor >= 0 || !allow_dynamic)
2806			return minor;
2807	}
2808
2809	return ida_alloc_range(&input_ida, INPUT_FIRST_DYNAMIC_DEV,
2810			       INPUT_MAX_CHAR_DEVICES - 1, GFP_KERNEL);
 
2811}
2812EXPORT_SYMBOL(input_get_new_minor);
2813
2814/**
2815 * input_free_minor - release previously allocated minor
2816 * @minor: minor to be released
2817 *
2818 * This function releases previously allocated input minor so that it can be
2819 * reused later.
2820 */
2821void input_free_minor(unsigned int minor)
2822{
2823	ida_free(&input_ida, minor);
2824}
2825EXPORT_SYMBOL(input_free_minor);
2826
2827static int __init input_init(void)
2828{
2829	int err;
2830
2831	err = class_register(&input_class);
2832	if (err) {
2833		pr_err("unable to register input_dev class\n");
2834		return err;
2835	}
2836
2837	err = input_proc_init();
2838	if (err)
2839		goto fail1;
2840
2841	err = register_chrdev_region(MKDEV(INPUT_MAJOR, 0),
2842				     INPUT_MAX_CHAR_DEVICES, "input");
2843	if (err) {
2844		pr_err("unable to register char major %d", INPUT_MAJOR);
2845		goto fail2;
2846	}
2847
2848	return 0;
2849
2850 fail2:	input_proc_exit();
2851 fail1:	class_unregister(&input_class);
2852	return err;
2853}
2854
2855static void __exit input_exit(void)
2856{
2857	input_proc_exit();
2858	unregister_chrdev_region(MKDEV(INPUT_MAJOR, 0),
2859				 INPUT_MAX_CHAR_DEVICES);
2860	class_unregister(&input_class);
2861}
2862
2863subsys_initcall(input_init);
2864module_exit(input_exit);