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