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/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(*dev->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
 936bool input_match_device_id(const struct input_dev *dev,
 937                           const struct input_device_id *id)
 938{
 939        if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
 940                if (id->bustype != dev->id.bustype)
 941                        return false;
 942
 943        if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
 944                if (id->vendor != dev->id.vendor)
 945                        return false;
 946
 947        if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
 948                if (id->product != dev->id.product)
 949                        return false;
 950
 951        if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
 952                if (id->version != dev->id.version)
 953                        return false;
 954
 955        if (!bitmap_subset(id->evbit, dev->evbit, EV_MAX) ||
 956            !bitmap_subset(id->keybit, dev->keybit, KEY_MAX) ||
 957            !bitmap_subset(id->relbit, dev->relbit, REL_MAX) ||
 958            !bitmap_subset(id->absbit, dev->absbit, ABS_MAX) ||
 959            !bitmap_subset(id->mscbit, dev->mscbit, MSC_MAX) ||
 960            !bitmap_subset(id->ledbit, dev->ledbit, LED_MAX) ||
 961            !bitmap_subset(id->sndbit, dev->sndbit, SND_MAX) ||
 962            !bitmap_subset(id->ffbit, dev->ffbit, FF_MAX) ||
 963            !bitmap_subset(id->swbit, dev->swbit, SW_MAX) ||
 964            !bitmap_subset(id->propbit, dev->propbit, INPUT_PROP_MAX)) {
 965                return false;
 966        }
 967
 968        return true;
 969}
 970EXPORT_SYMBOL(input_match_device_id);
 971
 972static const struct input_device_id *input_match_device(struct input_handler *handler,
 973                                                        struct input_dev *dev)
 974{
 975        const struct input_device_id *id;
 976
 977        for (id = handler->id_table; id->flags || id->driver_info; id++) {
 978                if (input_match_device_id(dev, id) &&
 979                    (!handler->match || handler->match(handler, dev))) {
 980                        return id;
 981                }
 982        }
 983
 984        return NULL;
 985}
 986
 987static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
 988{
 989        const struct input_device_id *id;
 990        int error;
 991
 992        id = input_match_device(handler, dev);
 993        if (!id)
 994                return -ENODEV;
 995
 996        error = handler->connect(handler, dev, id);
 997        if (error && error != -ENODEV)
 998                pr_err("failed to attach handler %s to device %s, error: %d\n",
 999                       handler->name, kobject_name(&dev->dev.kobj), error);
1000
1001        return error;
1002}
1003
1004#ifdef CONFIG_COMPAT
1005
1006static int input_bits_to_string(char *buf, int buf_size,
1007                                unsigned long bits, bool skip_empty)
1008{
1009        int len = 0;
1010
1011        if (in_compat_syscall()) {
1012                u32 dword = bits >> 32;
1013                if (dword || !skip_empty)
1014                        len += snprintf(buf, buf_size, "%x ", dword);
1015
1016                dword = bits & 0xffffffffUL;
1017                if (dword || !skip_empty || len)
1018                        len += snprintf(buf + len, max(buf_size - len, 0),
1019                                        "%x", dword);
1020        } else {
1021                if (bits || !skip_empty)
1022                        len += snprintf(buf, buf_size, "%lx", bits);
1023        }
1024
1025        return len;
1026}
1027
1028#else /* !CONFIG_COMPAT */
1029
1030static int input_bits_to_string(char *buf, int buf_size,
1031                                unsigned long bits, bool skip_empty)
1032{
1033        return bits || !skip_empty ?
1034                snprintf(buf, buf_size, "%lx", bits) : 0;
1035}
1036
1037#endif
1038
1039#ifdef CONFIG_PROC_FS
1040
1041static struct proc_dir_entry *proc_bus_input_dir;
1042static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
1043static int input_devices_state;
1044
1045static inline void input_wakeup_procfs_readers(void)
1046{
1047        input_devices_state++;
1048        wake_up(&input_devices_poll_wait);
1049}
1050
1051static unsigned int input_proc_devices_poll(struct file *file, poll_table *wait)
1052{
1053        poll_wait(file, &input_devices_poll_wait, wait);
1054        if (file->f_version != input_devices_state) {
1055                file->f_version = input_devices_state;
1056                return POLLIN | POLLRDNORM;
1057        }
1058
1059        return 0;
1060}
1061
1062union input_seq_state {
1063        struct {
1064                unsigned short pos;
1065                bool mutex_acquired;
1066        };
1067        void *p;
1068};
1069
1070static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
1071{
1072        union input_seq_state *state = (union input_seq_state *)&seq->private;
1073        int error;
1074
1075        /* We need to fit into seq->private pointer */
1076        BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1077
1078        error = mutex_lock_interruptible(&input_mutex);
1079        if (error) {
1080                state->mutex_acquired = false;
1081                return ERR_PTR(error);
1082        }
1083
1084        state->mutex_acquired = true;
1085
1086        return seq_list_start(&input_dev_list, *pos);
1087}
1088
1089static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1090{
1091        return seq_list_next(v, &input_dev_list, pos);
1092}
1093
1094static void input_seq_stop(struct seq_file *seq, void *v)
1095{
1096        union input_seq_state *state = (union input_seq_state *)&seq->private;
1097
1098        if (state->mutex_acquired)
1099                mutex_unlock(&input_mutex);
1100}
1101
1102static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
1103                                   unsigned long *bitmap, int max)
1104{
1105        int i;
1106        bool skip_empty = true;
1107        char buf[18];
1108
1109        seq_printf(seq, "B: %s=", name);
1110
1111        for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1112                if (input_bits_to_string(buf, sizeof(buf),
1113                                         bitmap[i], skip_empty)) {
1114                        skip_empty = false;
1115                        seq_printf(seq, "%s%s", buf, i > 0 ? " " : "");
1116                }
1117        }
1118
1119        /*
1120         * If no output was produced print a single 0.
1121         */
1122        if (skip_empty)
1123                seq_putc(seq, '0');
1124
1125        seq_putc(seq, '\n');
1126}
1127
1128static int input_devices_seq_show(struct seq_file *seq, void *v)
1129{
1130        struct input_dev *dev = container_of(v, struct input_dev, node);
1131        const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1132        struct input_handle *handle;
1133
1134        seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
1135                   dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
1136
1137        seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
1138        seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
1139        seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
1140        seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
1141        seq_puts(seq, "H: Handlers=");
1142
1143        list_for_each_entry(handle, &dev->h_list, d_node)
1144                seq_printf(seq, "%s ", handle->name);
1145        seq_putc(seq, '\n');
1146
1147        input_seq_print_bitmap(seq, "PROP", dev->propbit, INPUT_PROP_MAX);
1148
1149        input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
1150        if (test_bit(EV_KEY, dev->evbit))
1151                input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
1152        if (test_bit(EV_REL, dev->evbit))
1153                input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
1154        if (test_bit(EV_ABS, dev->evbit))
1155                input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
1156        if (test_bit(EV_MSC, dev->evbit))
1157                input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
1158        if (test_bit(EV_LED, dev->evbit))
1159                input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
1160        if (test_bit(EV_SND, dev->evbit))
1161                input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
1162        if (test_bit(EV_FF, dev->evbit))
1163                input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
1164        if (test_bit(EV_SW, dev->evbit))
1165                input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);
1166
1167        seq_putc(seq, '\n');
1168
1169        kfree(path);
1170        return 0;
1171}
1172
1173static const struct seq_operations input_devices_seq_ops = {
1174        .start  = input_devices_seq_start,
1175        .next   = input_devices_seq_next,
1176        .stop   = input_seq_stop,
1177        .show   = input_devices_seq_show,
1178};
1179
1180static int input_proc_devices_open(struct inode *inode, struct file *file)
1181{
1182        return seq_open(file, &input_devices_seq_ops);
1183}
1184
1185static const struct file_operations input_devices_fileops = {
1186        .owner          = THIS_MODULE,
1187        .open           = input_proc_devices_open,
1188        .poll           = input_proc_devices_poll,
1189        .read           = seq_read,
1190        .llseek         = seq_lseek,
1191        .release        = seq_release,
1192};
1193
1194static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
1195{
1196        union input_seq_state *state = (union input_seq_state *)&seq->private;
1197        int error;
1198
1199        /* We need to fit into seq->private pointer */
1200        BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1201
1202        error = mutex_lock_interruptible(&input_mutex);
1203        if (error) {
1204                state->mutex_acquired = false;
1205                return ERR_PTR(error);
1206        }
1207
1208        state->mutex_acquired = true;
1209        state->pos = *pos;
1210
1211        return seq_list_start(&input_handler_list, *pos);
1212}
1213
1214static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1215{
1216        union input_seq_state *state = (union input_seq_state *)&seq->private;
1217
1218        state->pos = *pos + 1;
1219        return seq_list_next(v, &input_handler_list, pos);
1220}
1221
1222static int input_handlers_seq_show(struct seq_file *seq, void *v)
1223{
1224        struct input_handler *handler = container_of(v, struct input_handler, node);
1225        union input_seq_state *state = (union input_seq_state *)&seq->private;
1226
1227        seq_printf(seq, "N: Number=%u Name=%s", state->pos, handler->name);
1228        if (handler->filter)
1229                seq_puts(seq, " (filter)");
1230        if (handler->legacy_minors)
1231                seq_printf(seq, " Minor=%d", handler->minor);
1232        seq_putc(seq, '\n');
1233
1234        return 0;
1235}
1236
1237static const struct seq_operations input_handlers_seq_ops = {
1238        .start  = input_handlers_seq_start,
1239        .next   = input_handlers_seq_next,
1240        .stop   = input_seq_stop,
1241        .show   = input_handlers_seq_show,
1242};
1243
1244static int input_proc_handlers_open(struct inode *inode, struct file *file)
1245{
1246        return seq_open(file, &input_handlers_seq_ops);
1247}
1248
1249static const struct file_operations input_handlers_fileops = {
1250        .owner          = THIS_MODULE,
1251        .open           = input_proc_handlers_open,
1252        .read           = seq_read,
1253        .llseek         = seq_lseek,
1254        .release        = seq_release,
1255};
1256
1257static int __init input_proc_init(void)
1258{
1259        struct proc_dir_entry *entry;
1260
1261        proc_bus_input_dir = proc_mkdir("bus/input", NULL);
1262        if (!proc_bus_input_dir)
1263                return -ENOMEM;
1264
1265        entry = proc_create("devices", 0, proc_bus_input_dir,
1266                            &input_devices_fileops);
1267        if (!entry)
1268                goto fail1;
1269
1270        entry = proc_create("handlers", 0, proc_bus_input_dir,
1271                            &input_handlers_fileops);
1272        if (!entry)
1273                goto fail2;
1274
1275        return 0;
1276
1277 fail2: remove_proc_entry("devices", proc_bus_input_dir);
1278 fail1: remove_proc_entry("bus/input", NULL);
1279        return -ENOMEM;
1280}
1281
1282static void input_proc_exit(void)
1283{
1284        remove_proc_entry("devices", proc_bus_input_dir);
1285        remove_proc_entry("handlers", proc_bus_input_dir);
1286        remove_proc_entry("bus/input", NULL);
1287}
1288
1289#else /* !CONFIG_PROC_FS */
1290static inline void input_wakeup_procfs_readers(void) { }
1291static inline int input_proc_init(void) { return 0; }
1292static inline void input_proc_exit(void) { }
1293#endif
1294
1295#define INPUT_DEV_STRING_ATTR_SHOW(name)                                \
1296static ssize_t input_dev_show_##name(struct device *dev,                \
1297                                     struct device_attribute *attr,     \
1298                                     char *buf)                         \
1299{                                                                       \
1300        struct input_dev *input_dev = to_input_dev(dev);                \
1301                                                                        \
1302        return scnprintf(buf, PAGE_SIZE, "%s\n",                        \
1303                         input_dev->name ? input_dev->name : "");       \
1304}                                                                       \
1305static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
1306
1307INPUT_DEV_STRING_ATTR_SHOW(name);
1308INPUT_DEV_STRING_ATTR_SHOW(phys);
1309INPUT_DEV_STRING_ATTR_SHOW(uniq);
1310
1311static int input_print_modalias_bits(char *buf, int size,
1312                                     char name, unsigned long *bm,
1313                                     unsigned int min_bit, unsigned int max_bit)
1314{
1315        int len = 0, i;
1316
1317        len += snprintf(buf, max(size, 0), "%c", name);
1318        for (i = min_bit; i < max_bit; i++)
1319                if (bm[BIT_WORD(i)] & BIT_MASK(i))
1320                        len += snprintf(buf + len, max(size - len, 0), "%X,", i);
1321        return len;
1322}
1323
1324static int input_print_modalias(char *buf, int size, struct input_dev *id,
1325                                int add_cr)
1326{
1327        int len;
1328
1329        len = snprintf(buf, max(size, 0),
1330                       "input:b%04Xv%04Xp%04Xe%04X-",
1331                       id->id.bustype, id->id.vendor,
1332                       id->id.product, id->id.version);
1333
1334        len += input_print_modalias_bits(buf + len, size - len,
1335                                'e', id->evbit, 0, EV_MAX);
1336        len += input_print_modalias_bits(buf + len, size - len,
1337                                'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
1338        len += input_print_modalias_bits(buf + len, size - len,
1339                                'r', id->relbit, 0, REL_MAX);
1340        len += input_print_modalias_bits(buf + len, size - len,
1341                                'a', id->absbit, 0, ABS_MAX);
1342        len += input_print_modalias_bits(buf + len, size - len,
1343                                'm', id->mscbit, 0, MSC_MAX);
1344        len += input_print_modalias_bits(buf + len, size - len,
1345                                'l', id->ledbit, 0, LED_MAX);
1346        len += input_print_modalias_bits(buf + len, size - len,
1347                                's', id->sndbit, 0, SND_MAX);
1348        len += input_print_modalias_bits(buf + len, size - len,
1349                                'f', id->ffbit, 0, FF_MAX);
1350        len += input_print_modalias_bits(buf + len, size - len,
1351                                'w', id->swbit, 0, SW_MAX);
1352
1353        if (add_cr)
1354                len += snprintf(buf + len, max(size - len, 0), "\n");
1355
1356        return len;
1357}
1358
1359static ssize_t input_dev_show_modalias(struct device *dev,
1360                                       struct device_attribute *attr,
1361                                       char *buf)
1362{
1363        struct input_dev *id = to_input_dev(dev);
1364        ssize_t len;
1365
1366        len = input_print_modalias(buf, PAGE_SIZE, id, 1);
1367
1368        return min_t(int, len, PAGE_SIZE);
1369}
1370static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
1371
1372static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1373                              int max, int add_cr);
1374
1375static ssize_t input_dev_show_properties(struct device *dev,
1376                                         struct device_attribute *attr,
1377                                         char *buf)
1378{
1379        struct input_dev *input_dev = to_input_dev(dev);
1380        int len = input_print_bitmap(buf, PAGE_SIZE, input_dev->propbit,
1381                                     INPUT_PROP_MAX, true);
1382        return min_t(int, len, PAGE_SIZE);
1383}
1384static DEVICE_ATTR(properties, S_IRUGO, input_dev_show_properties, NULL);
1385
1386static struct attribute *input_dev_attrs[] = {
1387        &dev_attr_name.attr,
1388        &dev_attr_phys.attr,
1389        &dev_attr_uniq.attr,
1390        &dev_attr_modalias.attr,
1391        &dev_attr_properties.attr,
1392        NULL
1393};
1394
1395static const struct attribute_group input_dev_attr_group = {
1396        .attrs  = input_dev_attrs,
1397};
1398
1399#define INPUT_DEV_ID_ATTR(name)                                         \
1400static ssize_t input_dev_show_id_##name(struct device *dev,             \
1401                                        struct device_attribute *attr,  \
1402                                        char *buf)                      \
1403{                                                                       \
1404        struct input_dev *input_dev = to_input_dev(dev);                \
1405        return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name); \
1406}                                                                       \
1407static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
1408
1409INPUT_DEV_ID_ATTR(bustype);
1410INPUT_DEV_ID_ATTR(vendor);
1411INPUT_DEV_ID_ATTR(product);
1412INPUT_DEV_ID_ATTR(version);
1413
1414static struct attribute *input_dev_id_attrs[] = {
1415        &dev_attr_bustype.attr,
1416        &dev_attr_vendor.attr,
1417        &dev_attr_product.attr,
1418        &dev_attr_version.attr,
1419        NULL
1420};
1421
1422static const struct attribute_group input_dev_id_attr_group = {
1423        .name   = "id",
1424        .attrs  = input_dev_id_attrs,
1425};
1426
1427static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1428                              int max, int add_cr)
1429{
1430        int i;
1431        int len = 0;
1432        bool skip_empty = true;
1433
1434        for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1435                len += input_bits_to_string(buf + len, max(buf_size - len, 0),
1436                                            bitmap[i], skip_empty);
1437                if (len) {
1438                        skip_empty = false;
1439                        if (i > 0)
1440                                len += snprintf(buf + len, max(buf_size - len, 0), " ");
1441                }
1442        }
1443
1444        /*
1445         * If no output was produced print a single 0.
1446         */
1447        if (len == 0)
1448                len = snprintf(buf, buf_size, "%d", 0);
1449
1450        if (add_cr)
1451                len += snprintf(buf + len, max(buf_size - len, 0), "\n");
1452
1453        return len;
1454}
1455
1456#define INPUT_DEV_CAP_ATTR(ev, bm)                                      \
1457static ssize_t input_dev_show_cap_##bm(struct device *dev,              \
1458                                       struct device_attribute *attr,   \
1459                                       char *buf)                       \
1460{                                                                       \
1461        struct input_dev *input_dev = to_input_dev(dev);                \
1462        int len = input_print_bitmap(buf, PAGE_SIZE,                    \
1463                                     input_dev->bm##bit, ev##_MAX,      \
1464                                     true);                             \
1465        return min_t(int, len, PAGE_SIZE);                              \
1466}                                                                       \
1467static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
1468
1469INPUT_DEV_CAP_ATTR(EV, ev);
1470INPUT_DEV_CAP_ATTR(KEY, key);
1471INPUT_DEV_CAP_ATTR(REL, rel);
1472INPUT_DEV_CAP_ATTR(ABS, abs);
1473INPUT_DEV_CAP_ATTR(MSC, msc);
1474INPUT_DEV_CAP_ATTR(LED, led);
1475INPUT_DEV_CAP_ATTR(SND, snd);
1476INPUT_DEV_CAP_ATTR(FF, ff);
1477INPUT_DEV_CAP_ATTR(SW, sw);
1478
1479static struct attribute *input_dev_caps_attrs[] = {
1480        &dev_attr_ev.attr,
1481        &dev_attr_key.attr,
1482        &dev_attr_rel.attr,
1483        &dev_attr_abs.attr,
1484        &dev_attr_msc.attr,
1485        &dev_attr_led.attr,
1486        &dev_attr_snd.attr,
1487        &dev_attr_ff.attr,
1488        &dev_attr_sw.attr,
1489        NULL
1490};
1491
1492static const struct attribute_group input_dev_caps_attr_group = {
1493        .name   = "capabilities",
1494        .attrs  = input_dev_caps_attrs,
1495};
1496
1497static const struct attribute_group *input_dev_attr_groups[] = {
1498        &input_dev_attr_group,
1499        &input_dev_id_attr_group,
1500        &input_dev_caps_attr_group,
1501        NULL
1502};
1503
1504static void input_dev_release(struct device *device)
1505{
1506        struct input_dev *dev = to_input_dev(device);
1507
1508        input_ff_destroy(dev);
1509        input_mt_destroy_slots(dev);
1510        kfree(dev->absinfo);
1511        kfree(dev->vals);
1512        kfree(dev);
1513
1514        module_put(THIS_MODULE);
1515}
1516
1517/*
1518 * Input uevent interface - loading event handlers based on
1519 * device bitfields.
1520 */
1521static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
1522                                   const char *name, unsigned long *bitmap, int max)
1523{
1524        int len;
1525
1526        if (add_uevent_var(env, "%s", name))
1527                return -ENOMEM;
1528
1529        len = input_print_bitmap(&env->buf[env->buflen - 1],
1530                                 sizeof(env->buf) - env->buflen,
1531                                 bitmap, max, false);
1532        if (len >= (sizeof(env->buf) - env->buflen))
1533                return -ENOMEM;
1534
1535        env->buflen += len;
1536        return 0;
1537}
1538
1539static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
1540                                         struct input_dev *dev)
1541{
1542        int len;
1543
1544        if (add_uevent_var(env, "MODALIAS="))
1545                return -ENOMEM;
1546
1547        len = input_print_modalias(&env->buf[env->buflen - 1],
1548                                   sizeof(env->buf) - env->buflen,
1549                                   dev, 0);
1550        if (len >= (sizeof(env->buf) - env->buflen))
1551                return -ENOMEM;
1552
1553        env->buflen += len;
1554        return 0;
1555}
1556
1557#define INPUT_ADD_HOTPLUG_VAR(fmt, val...)                              \
1558        do {                                                            \
1559                int err = add_uevent_var(env, fmt, val);                \
1560                if (err)                                                \
1561                        return err;                                     \
1562        } while (0)
1563
1564#define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max)                         \
1565        do {                                                            \
1566                int err = input_add_uevent_bm_var(env, name, bm, max);  \
1567                if (err)                                                \
1568                        return err;                                     \
1569        } while (0)
1570
1571#define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev)                             \
1572        do {                                                            \
1573                int err = input_add_uevent_modalias_var(env, dev);      \
1574                if (err)                                                \
1575                        return err;                                     \
1576        } while (0)
1577
1578static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
1579{
1580        struct input_dev *dev = to_input_dev(device);
1581
1582        INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
1583                                dev->id.bustype, dev->id.vendor,
1584                                dev->id.product, dev->id.version);
1585        if (dev->name)
1586                INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
1587        if (dev->phys)
1588                INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
1589        if (dev->uniq)
1590                INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
1591
1592        INPUT_ADD_HOTPLUG_BM_VAR("PROP=", dev->propbit, INPUT_PROP_MAX);
1593
1594        INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
1595        if (test_bit(EV_KEY, dev->evbit))
1596                INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
1597        if (test_bit(EV_REL, dev->evbit))
1598                INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
1599        if (test_bit(EV_ABS, dev->evbit))
1600                INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
1601        if (test_bit(EV_MSC, dev->evbit))
1602                INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
1603        if (test_bit(EV_LED, dev->evbit))
1604                INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
1605        if (test_bit(EV_SND, dev->evbit))
1606                INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
1607        if (test_bit(EV_FF, dev->evbit))
1608                INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
1609        if (test_bit(EV_SW, dev->evbit))
1610                INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
1611
1612        INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
1613
1614        return 0;
1615}
1616
1617#define INPUT_DO_TOGGLE(dev, type, bits, on)                            \
1618        do {                                                            \
1619                int i;                                                  \
1620                bool active;                                            \
1621                                                                        \
1622                if (!test_bit(EV_##type, dev->evbit))                   \
1623                        break;                                          \
1624                                                                        \
1625                for_each_set_bit(i, dev->bits##bit, type##_CNT) {       \
1626                        active = test_bit(i, dev->bits);                \
1627                        if (!active && !on)                             \
1628                                continue;                               \
1629                                                                        \
1630                        dev->event(dev, EV_##type, i, on ? active : 0); \
1631                }                                                       \
1632        } while (0)
1633
1634static void input_dev_toggle(struct input_dev *dev, bool activate)
1635{
1636        if (!dev->event)
1637                return;
1638
1639        INPUT_DO_TOGGLE(dev, LED, led, activate);
1640        INPUT_DO_TOGGLE(dev, SND, snd, activate);
1641
1642        if (activate && test_bit(EV_REP, dev->evbit)) {
1643                dev->event(dev, EV_REP, REP_PERIOD, dev->rep[REP_PERIOD]);
1644                dev->event(dev, EV_REP, REP_DELAY, dev->rep[REP_DELAY]);
1645        }
1646}
1647
1648/**
1649 * input_reset_device() - reset/restore the state of input device
1650 * @dev: input device whose state needs to be reset
1651 *
1652 * This function tries to reset the state of an opened input device and
1653 * bring internal state and state if the hardware in sync with each other.
1654 * We mark all keys as released, restore LED state, repeat rate, etc.
1655 */
1656void input_reset_device(struct input_dev *dev)
1657{
1658        unsigned long flags;
1659
1660        mutex_lock(&dev->mutex);
1661        spin_lock_irqsave(&dev->event_lock, flags);
1662
1663        input_dev_toggle(dev, true);
1664        input_dev_release_keys(dev);
1665
1666        spin_unlock_irqrestore(&dev->event_lock, flags);
1667        mutex_unlock(&dev->mutex);
1668}
1669EXPORT_SYMBOL(input_reset_device);
1670
1671#ifdef CONFIG_PM_SLEEP
1672static int input_dev_suspend(struct device *dev)
1673{
1674        struct input_dev *input_dev = to_input_dev(dev);
1675
1676        spin_lock_irq(&input_dev->event_lock);
1677
1678        /*
1679         * Keys that are pressed now are unlikely to be
1680         * still pressed when we resume.
1681         */
1682        input_dev_release_keys(input_dev);
1683
1684        /* Turn off LEDs and sounds, if any are active. */
1685        input_dev_toggle(input_dev, false);
1686
1687        spin_unlock_irq(&input_dev->event_lock);
1688
1689        return 0;
1690}
1691
1692static int input_dev_resume(struct device *dev)
1693{
1694        struct input_dev *input_dev = to_input_dev(dev);
1695
1696        spin_lock_irq(&input_dev->event_lock);
1697
1698        /* Restore state of LEDs and sounds, if any were active. */
1699        input_dev_toggle(input_dev, true);
1700
1701        spin_unlock_irq(&input_dev->event_lock);
1702
1703        return 0;
1704}
1705
1706static int input_dev_freeze(struct device *dev)
1707{
1708        struct input_dev *input_dev = to_input_dev(dev);
1709
1710        spin_lock_irq(&input_dev->event_lock);
1711
1712        /*
1713         * Keys that are pressed now are unlikely to be
1714         * still pressed when we resume.
1715         */
1716        input_dev_release_keys(input_dev);
1717
1718        spin_unlock_irq(&input_dev->event_lock);
1719
1720        return 0;
1721}
1722
1723static int input_dev_poweroff(struct device *dev)
1724{
1725        struct input_dev *input_dev = to_input_dev(dev);
1726
1727        spin_lock_irq(&input_dev->event_lock);
1728
1729        /* Turn off LEDs and sounds, if any are active. */
1730        input_dev_toggle(input_dev, false);
1731
1732        spin_unlock_irq(&input_dev->event_lock);
1733
1734        return 0;
1735}
1736
1737static const struct dev_pm_ops input_dev_pm_ops = {
1738        .suspend        = input_dev_suspend,
1739        .resume         = input_dev_resume,
1740        .freeze         = input_dev_freeze,
1741        .poweroff       = input_dev_poweroff,
1742        .restore        = input_dev_resume,
1743};
1744#endif /* CONFIG_PM */
1745
1746static const struct device_type input_dev_type = {
1747        .groups         = input_dev_attr_groups,
1748        .release        = input_dev_release,
1749        .uevent         = input_dev_uevent,
1750#ifdef CONFIG_PM_SLEEP
1751        .pm             = &input_dev_pm_ops,
1752#endif
1753};
1754
1755static char *input_devnode(struct device *dev, umode_t *mode)
1756{
1757        return kasprintf(GFP_KERNEL, "input/%s", dev_name(dev));
1758}
1759
1760struct class input_class = {
1761        .name           = "input",
1762        .devnode        = input_devnode,
1763};
1764EXPORT_SYMBOL_GPL(input_class);
1765
1766/**
1767 * input_allocate_device - allocate memory for new input device
1768 *
1769 * Returns prepared struct input_dev or %NULL.
1770 *
1771 * NOTE: Use input_free_device() to free devices that have not been
1772 * registered; input_unregister_device() should be used for already
1773 * registered devices.
1774 */
1775struct input_dev *input_allocate_device(void)
1776{
1777        static atomic_t input_no = ATOMIC_INIT(-1);
1778        struct input_dev *dev;
1779
1780        dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1781        if (dev) {
1782                dev->dev.type = &input_dev_type;
1783                dev->dev.class = &input_class;
1784                device_initialize(&dev->dev);
1785                mutex_init(&dev->mutex);
1786                spin_lock_init(&dev->event_lock);
1787                init_timer(&dev->timer);
1788                INIT_LIST_HEAD(&dev->h_list);
1789                INIT_LIST_HEAD(&dev->node);
1790
1791                dev_set_name(&dev->dev, "input%lu",
1792                             (unsigned long)atomic_inc_return(&input_no));
1793
1794                __module_get(THIS_MODULE);
1795        }
1796
1797        return dev;
1798}
1799EXPORT_SYMBOL(input_allocate_device);
1800
1801struct input_devres {
1802        struct input_dev *input;
1803};
1804
1805static int devm_input_device_match(struct device *dev, void *res, void *data)
1806{
1807        struct input_devres *devres = res;
1808
1809        return devres->input == data;
1810}
1811
1812static void devm_input_device_release(struct device *dev, void *res)
1813{
1814        struct input_devres *devres = res;
1815        struct input_dev *input = devres->input;
1816
1817        dev_dbg(dev, "%s: dropping reference to %s\n",
1818                __func__, dev_name(&input->dev));
1819        input_put_device(input);
1820}
1821
1822/**
1823 * devm_input_allocate_device - allocate managed input device
1824 * @dev: device owning the input device being created
1825 *
1826 * Returns prepared struct input_dev or %NULL.
1827 *
1828 * Managed input devices do not need to be explicitly unregistered or
1829 * freed as it will be done automatically when owner device unbinds from
1830 * its driver (or binding fails). Once managed input device is allocated,
1831 * it is ready to be set up and registered in the same fashion as regular
1832 * input device. There are no special devm_input_device_[un]register()
1833 * variants, regular ones work with both managed and unmanaged devices,
1834 * should you need them. In most cases however, managed input device need
1835 * not be explicitly unregistered or freed.
1836 *
1837 * NOTE: the owner device is set up as parent of input device and users
1838 * should not override it.
1839 */
1840struct input_dev *devm_input_allocate_device(struct device *dev)
1841{
1842        struct input_dev *input;
1843        struct input_devres *devres;
1844
1845        devres = devres_alloc(devm_input_device_release,
1846                              sizeof(*devres), GFP_KERNEL);
1847        if (!devres)
1848                return NULL;
1849
1850        input = input_allocate_device();
1851        if (!input) {
1852                devres_free(devres);
1853                return NULL;
1854        }
1855
1856        input->dev.parent = dev;
1857        input->devres_managed = true;
1858
1859        devres->input = input;
1860        devres_add(dev, devres);
1861
1862        return input;
1863}
1864EXPORT_SYMBOL(devm_input_allocate_device);
1865
1866/**
1867 * input_free_device - free memory occupied by input_dev structure
1868 * @dev: input device to free
1869 *
1870 * This function should only be used if input_register_device()
1871 * was not called yet or if it failed. Once device was registered
1872 * use input_unregister_device() and memory will be freed once last
1873 * reference to the device is dropped.
1874 *
1875 * Device should be allocated by input_allocate_device().
1876 *
1877 * NOTE: If there are references to the input device then memory
1878 * will not be freed until last reference is dropped.
1879 */
1880void input_free_device(struct input_dev *dev)
1881{
1882        if (dev) {
1883                if (dev->devres_managed)
1884                        WARN_ON(devres_destroy(dev->dev.parent,
1885                                                devm_input_device_release,
1886                                                devm_input_device_match,
1887                                                dev));
1888                input_put_device(dev);
1889        }
1890}
1891EXPORT_SYMBOL(input_free_device);
1892
1893/**
1894 * input_set_capability - mark device as capable of a certain event
1895 * @dev: device that is capable of emitting or accepting event
1896 * @type: type of the event (EV_KEY, EV_REL, etc...)
1897 * @code: event code
1898 *
1899 * In addition to setting up corresponding bit in appropriate capability
1900 * bitmap the function also adjusts dev->evbit.
1901 */
1902void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
1903{
1904        switch (type) {
1905        case EV_KEY:
1906                __set_bit(code, dev->keybit);
1907                break;
1908
1909        case EV_REL:
1910                __set_bit(code, dev->relbit);
1911                break;
1912
1913        case EV_ABS:
1914                input_alloc_absinfo(dev);
1915                if (!dev->absinfo)
1916                        return;
1917
1918                __set_bit(code, dev->absbit);
1919                break;
1920
1921        case EV_MSC:
1922                __set_bit(code, dev->mscbit);
1923                break;
1924
1925        case EV_SW:
1926                __set_bit(code, dev->swbit);
1927                break;
1928
1929        case EV_LED:
1930                __set_bit(code, dev->ledbit);
1931                break;
1932
1933        case EV_SND:
1934                __set_bit(code, dev->sndbit);
1935                break;
1936
1937        case EV_FF:
1938                __set_bit(code, dev->ffbit);
1939                break;
1940
1941        case EV_PWR:
1942                /* do nothing */
1943                break;
1944
1945        default:
1946                pr_err("input_set_capability: unknown type %u (code %u)\n",
1947                       type, code);
1948                dump_stack();
1949                return;
1950        }
1951
1952        __set_bit(type, dev->evbit);
1953}
1954EXPORT_SYMBOL(input_set_capability);
1955
1956static unsigned int input_estimate_events_per_packet(struct input_dev *dev)
1957{
1958        int mt_slots;
1959        int i;
1960        unsigned int events;
1961
1962        if (dev->mt) {
1963                mt_slots = dev->mt->num_slots;
1964        } else if (test_bit(ABS_MT_TRACKING_ID, dev->absbit)) {
1965                mt_slots = dev->absinfo[ABS_MT_TRACKING_ID].maximum -
1966                           dev->absinfo[ABS_MT_TRACKING_ID].minimum + 1,
1967                mt_slots = clamp(mt_slots, 2, 32);
1968        } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
1969                mt_slots = 2;
1970        } else {
1971                mt_slots = 0;
1972        }
1973
1974        events = mt_slots + 1; /* count SYN_MT_REPORT and SYN_REPORT */
1975
1976        if (test_bit(EV_ABS, dev->evbit))
1977                for_each_set_bit(i, dev->absbit, ABS_CNT)
1978                        events += input_is_mt_axis(i) ? mt_slots : 1;
1979
1980        if (test_bit(EV_REL, dev->evbit))
1981                events += bitmap_weight(dev->relbit, REL_CNT);
1982
1983        /* Make room for KEY and MSC events */
1984        events += 7;
1985
1986        return events;
1987}
1988
1989#define INPUT_CLEANSE_BITMASK(dev, type, bits)                          \
1990        do {                                                            \
1991                if (!test_bit(EV_##type, dev->evbit))                   \
1992                        memset(dev->bits##bit, 0,                       \
1993                                sizeof(dev->bits##bit));                \
1994        } while (0)
1995
1996static void input_cleanse_bitmasks(struct input_dev *dev)
1997{
1998        INPUT_CLEANSE_BITMASK(dev, KEY, key);
1999        INPUT_CLEANSE_BITMASK(dev, REL, rel);
2000        INPUT_CLEANSE_BITMASK(dev, ABS, abs);
2001        INPUT_CLEANSE_BITMASK(dev, MSC, msc);
2002        INPUT_CLEANSE_BITMASK(dev, LED, led);
2003        INPUT_CLEANSE_BITMASK(dev, SND, snd);
2004        INPUT_CLEANSE_BITMASK(dev, FF, ff);
2005        INPUT_CLEANSE_BITMASK(dev, SW, sw);
2006}
2007
2008static void __input_unregister_device(struct input_dev *dev)
2009{
2010        struct input_handle *handle, *next;
2011
2012        input_disconnect_device(dev);
2013
2014        mutex_lock(&input_mutex);
2015
2016        list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
2017                handle->handler->disconnect(handle);
2018        WARN_ON(!list_empty(&dev->h_list));
2019
2020        del_timer_sync(&dev->timer);
2021        list_del_init(&dev->node);
2022
2023        input_wakeup_procfs_readers();
2024
2025        mutex_unlock(&input_mutex);
2026
2027        device_del(&dev->dev);
2028}
2029
2030static void devm_input_device_unregister(struct device *dev, void *res)
2031{
2032        struct input_devres *devres = res;
2033        struct input_dev *input = devres->input;
2034
2035        dev_dbg(dev, "%s: unregistering device %s\n",
2036                __func__, dev_name(&input->dev));
2037        __input_unregister_device(input);
2038}
2039
2040/**
2041 * input_enable_softrepeat - enable software autorepeat
2042 * @dev: input device
2043 * @delay: repeat delay
2044 * @period: repeat period
2045 *
2046 * Enable software autorepeat on the input device.
2047 */
2048void input_enable_softrepeat(struct input_dev *dev, int delay, int period)
2049{
2050        dev->timer.data = (unsigned long) dev;
2051        dev->timer.function = input_repeat_key;
2052        dev->rep[REP_DELAY] = delay;
2053        dev->rep[REP_PERIOD] = period;
2054}
2055EXPORT_SYMBOL(input_enable_softrepeat);
2056
2057/**
2058 * input_register_device - register device with input core
2059 * @dev: device to be registered
2060 *
2061 * This function registers device with input core. The device must be
2062 * allocated with input_allocate_device() and all it's capabilities
2063 * set up before registering.
2064 * If function fails the device must be freed with input_free_device().
2065 * Once device has been successfully registered it can be unregistered
2066 * with input_unregister_device(); input_free_device() should not be
2067 * called in this case.
2068 *
2069 * Note that this function is also used to register managed input devices
2070 * (ones allocated with devm_input_allocate_device()). Such managed input
2071 * devices need not be explicitly unregistered or freed, their tear down
2072 * is controlled by the devres infrastructure. It is also worth noting
2073 * that tear down of managed input devices is internally a 2-step process:
2074 * registered managed input device is first unregistered, but stays in
2075 * memory and can still handle input_event() calls (although events will
2076 * not be delivered anywhere). The freeing of managed input device will
2077 * happen later, when devres stack is unwound to the point where device
2078 * allocation was made.
2079 */
2080int input_register_device(struct input_dev *dev)
2081{
2082        struct input_devres *devres = NULL;
2083        struct input_handler *handler;
2084        unsigned int packet_size;
2085        const char *path;
2086        int error;
2087
2088        if (test_bit(EV_ABS, dev->evbit) && !dev->absinfo) {
2089                dev_err(&dev->dev,
2090                        "Absolute device without dev->absinfo, refusing to register\n");
2091                return -EINVAL;
2092        }
2093
2094        if (dev->devres_managed) {
2095                devres = devres_alloc(devm_input_device_unregister,
2096                                      sizeof(*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);
2454