drivers/input/evdev.c

   1 /*
   2  * Event char devices, giving access to raw input device events.
   3  *
   4  * Copyright (c) 1999-2002 Vojtech Pavlik
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 as published by
   8  * the Free Software Foundation.
   9  */
  10
  11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  12
  13 #define EVDEV_MINOR_BASE        64
  14 #define EVDEV_MINORS            32
  15 #define EVDEV_MIN_BUFFER_SIZE   64U
  16 #define EVDEV_BUF_PACKETS       8
  17
  18 #include <linux/poll.h>
  19 #include <linux/sched.h>
  20 #include <linux/slab.h>
  21 #include <linux/vmalloc.h>
  22 #include <linux/mm.h>
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25 #include <linux/input/mt.h>
  26 #include <linux/major.h>
  27 #include <linux/device.h>
  28 #include <linux/cdev.h>
  29 #include "input-compat.h"
  30
  31 enum evdev_clock_type {
  32         EV_CLK_REAL = 0,
  33         EV_CLK_MONO,
  34         EV_CLK_BOOT,
  35         EV_CLK_MAX
  36 };
  37
  38 struct evdev {
  39         int open;
  40         struct input_handle handle;
  41         wait_queue_head_t wait;
  42         struct evdev_client __rcu *grab;
  43         struct list_head client_list;
  44         spinlock_t client_lock; /* protects client_list */
  45         struct mutex mutex;
  46         struct device dev;
  47         struct cdev cdev;
  48         bool exist;
  49 };
  50
  51 struct evdev_client {
  52         unsigned int head;
  53         unsigned int tail;
  54         unsigned int packet_head; /* [future] position of the first element of next packet */
  55         spinlock_t buffer_lock; /* protects access to buffer, head and tail */
  56         struct fasync_struct *fasync;
  57         struct evdev *evdev;
  58         struct list_head node;
  59         unsigned int clk_type;
  60         bool revoked;
  61         unsigned long *evmasks[EV_CNT];
  62         unsigned int bufsize;
  63         struct input_event buffer[];
  64 };
  65
  66 static size_t evdev_get_mask_cnt(unsigned int type)
  67 {
  68         static const size_t counts[EV_CNT] = {
  69                 /* EV_SYN==0 is EV_CNT, _not_ SYN_CNT, see EVIOCGBIT */
  70                 [EV_SYN]        = EV_CNT,
  71                 [EV_KEY]        = KEY_CNT,
  72                 [EV_REL]        = REL_CNT,
  73                 [EV_ABS]        = ABS_CNT,
  74                 [EV_MSC]        = MSC_CNT,
  75                 [EV_SW]         = SW_CNT,
  76                 [EV_LED]        = LED_CNT,
  77                 [EV_SND]        = SND_CNT,
  78                 [EV_FF]         = FF_CNT,
  79         };
  80
  81         return (type < EV_CNT) ? counts[type] : 0;
  82 }
  83
  84 /* requires the buffer lock to be held */
  85 static bool __evdev_is_filtered(struct evdev_client *client,
  86                                 unsigned int type,
  87                                 unsigned int code)
  88 {
  89         unsigned long *mask;
  90         size_t cnt;
  91
  92         /* EV_SYN and unknown codes are never filtered */
  93         if (type == EV_SYN || type >= EV_CNT)
  94                 return false;
  95
  96         /* first test whether the type is filtered */
  97         mask = client->evmasks[0];
  98         if (mask && !test_bit(type, mask))
  99                 return true;
 100
 101         /* unknown values are never filtered */
 102         cnt = evdev_get_mask_cnt(type);
 103         if (!cnt || code >= cnt)
 104                 return false;
 105
 106         mask = client->evmasks[type];
 107         return mask && !test_bit(code, mask);
 108 }
 109
 110 /* flush queued events of type @type, caller must hold client->buffer_lock */
 111 static void __evdev_flush_queue(struct evdev_client *client, unsigned int type)
 112 {
 113         unsigned int i, head, num;
 114         unsigned int mask = client->bufsize - 1;
 115         bool is_report;
 116         struct input_event *ev;
 117
 118         BUG_ON(type == EV_SYN);
 119
 120         head = client->tail;
 121         client->packet_head = client->tail;
 122
 123         /* init to 1 so a leading SYN_REPORT will not be dropped */
 124         num = 1;
 125
 126         for (i = client->tail; i != client->head; i = (i + 1) & mask) {
 127                 ev = &client->buffer[i];
 128                 is_report = ev->type == EV_SYN && ev->code == SYN_REPORT;
 129
 130                 if (ev->type == type) {
 131                         /* drop matched entry */
 132                         continue;
 133                 } else if (is_report && !num) {
 134                         /* drop empty SYN_REPORT groups */
 135                         continue;
 136                 } else if (head != i) {
 137                         /* move entry to fill the gap */
 138                         client->buffer[head].time = ev->time;
 139                         client->buffer[head].type = ev->type;
 140                         client->buffer[head].code = ev->code;
 141                         client->buffer[head].value = ev->value;
 142                 }
 143
 144                 num++;
 145                 head = (head + 1) & mask;
 146
 147                 if (is_report) {
 148                         num = 0;
 149                         client->packet_head = head;
 150                 }
 151         }
 152
 153         client->head = head;
 154 }
 155
 156 static void __evdev_queue_syn_dropped(struct evdev_client *client)
 157 {
 158         struct input_event ev;
 159         ktime_t time;
 160
 161         time = client->clk_type == EV_CLK_REAL ?
 162                         ktime_get_real() :
 163                         client->clk_type == EV_CLK_MONO ?
 164                                 ktime_get() :
 165                                 ktime_get_boottime();
 166
 167         ev.time = ktime_to_timeval(time);
 168         ev.type = EV_SYN;
 169         ev.code = SYN_DROPPED;
 170         ev.value = 0;
 171
 172         client->buffer[client->head++] = ev;
 173         client->head &= client->bufsize - 1;
 174
 175         if (unlikely(client->head == client->tail)) {
 176                 /* drop queue but keep our SYN_DROPPED event */
 177                 client->tail = (client->head - 1) & (client->bufsize - 1);
 178                 client->packet_head = client->tail;
 179         }
 180 }
 181
 182 static void evdev_queue_syn_dropped(struct evdev_client *client)
 183 {
 184         unsigned long flags;
 185
 186         spin_lock_irqsave(&client->buffer_lock, flags);
 187         __evdev_queue_syn_dropped(client);
 188         spin_unlock_irqrestore(&client->buffer_lock, flags);
 189 }
 190
 191 static int evdev_set_clk_type(struct evdev_client *client, unsigned int clkid)
 192 {
 193         unsigned long flags;
 194         unsigned int clk_type;
 195
 196         switch (clkid) {
 197
 198         case CLOCK_REALTIME:
 199                 clk_type = EV_CLK_REAL;
 200                 break;
 201         case CLOCK_MONOTONIC:
 202                 clk_type = EV_CLK_MONO;
 203                 break;
 204         case CLOCK_BOOTTIME:
 205                 clk_type = EV_CLK_BOOT;
 206                 break;
 207         default:
 208                 return -EINVAL;
 209         }
 210
 211         if (client->clk_type != clk_type) {
 212                 client->clk_type = clk_type;
 213
 214                 /*
 215                  * Flush pending events and queue SYN_DROPPED event,
 216                  * but only if the queue is not empty.
 217                  */
 218                 spin_lock_irqsave(&client->buffer_lock, flags);
 219
 220                 if (client->head != client->tail) {
 221                         client->packet_head = client->head = client->tail;
 222                         __evdev_queue_syn_dropped(client);
 223                 }
 224
 225                 spin_unlock_irqrestore(&client->buffer_lock, flags);
 226         }
 227
 228         return 0;
 229 }
 230
 231 static void __pass_event(struct evdev_client *client,
 232                          const struct input_event *event)
 233 {
 234         client->buffer[client->head++] = *event;
 235         client->head &= client->bufsize - 1;
 236
 237         if (unlikely(client->head == client->tail)) {
 238                 /*
 239                  * This effectively "drops" all unconsumed events, leaving
 240                  * EV_SYN/SYN_DROPPED plus the newest event in the queue.
 241                  */
 242                 client->tail = (client->head - 2) & (client->bufsize - 1);
 243
 244                 client->buffer[client->tail].time = event->time;
 245                 client->buffer[client->tail].type = EV_SYN;
 246                 client->buffer[client->tail].code = SYN_DROPPED;
 247                 client->buffer[client->tail].value = 0;
 248
 249                 client->packet_head = client->tail;
 250         }
 251
 252         if (event->type == EV_SYN && event->code == SYN_REPORT) {
 253                 client->packet_head = client->head;
 254                 kill_fasync(&client->fasync, SIGIO, POLL_IN);
 255         }
 256 }
 257
 258 static void evdev_pass_values(struct evdev_client *client,
 259                         const struct input_value *vals, unsigned int count,
 260                         ktime_t *ev_time)
 261 {
 262         struct evdev *evdev = client->evdev;
 263         const struct input_value *v;
 264         struct input_event event;
 265         bool wakeup = false;
 266
 267         if (client->revoked)
 268                 return;
 269
 270         event.time = ktime_to_timeval(ev_time[client->clk_type]);
 271
 272         /* Interrupts are disabled, just acquire the lock. */
 273         spin_lock(&client->buffer_lock);
 274
 275         for (v = vals; v != vals + count; v++) {
 276                 if (__evdev_is_filtered(client, v->type, v->code))
 277                         continue;
 278
 279                 if (v->type == EV_SYN && v->code == SYN_REPORT) {
 280                         /* drop empty SYN_REPORT */
 281                         if (client->packet_head == client->head)
 282                                 continue;
 283
 284                         wakeup = true;
 285                 }
 286
 287                 event.type = v->type;
 288                 event.code = v->code;
 289                 event.value = v->value;
 290                 __pass_event(client, &event);
 291         }
 292
 293         spin_unlock(&client->buffer_lock);
 294
 295         if (wakeup)
 296                 wake_up_interruptible(&evdev->wait);
 297 }
 298
 299 /*
 300  * Pass incoming events to all connected clients.
 301  */
 302 static void evdev_events(struct input_handle *handle,
 303                          const struct input_value *vals, unsigned int count)
 304 {
 305         struct evdev *evdev = handle->private;
 306         struct evdev_client *client;
 307         ktime_t ev_time[EV_CLK_MAX];
 308
 309         ev_time[EV_CLK_MONO] = ktime_get();
 310         ev_time[EV_CLK_REAL] = ktime_mono_to_real(ev_time[EV_CLK_MONO]);
 311         ev_time[EV_CLK_BOOT] = ktime_mono_to_any(ev_time[EV_CLK_MONO],
 312                                                  TK_OFFS_BOOT);
 313
 314         rcu_read_lock();
 315
 316         client = rcu_dereference(evdev->grab);
 317
 318         if (client)
 319                 evdev_pass_values(client, vals, count, ev_time);
 320         else
 321                 list_for_each_entry_rcu(client, &evdev->client_list, node)
 322                         evdev_pass_values(client, vals, count, ev_time);
 323
 324         rcu_read_unlock();
 325 }
 326
 327 /*
 328  * Pass incoming event to all connected clients.
 329  */
 330 static void evdev_event(struct input_handle *handle,
 331                         unsigned int type, unsigned int code, int value)
 332 {
 333         struct input_value vals[] = { { type, code, value } };
 334
 335         evdev_events(handle, vals, 1);
 336 }
 337
 338 static int evdev_fasync(int fd, struct file *file, int on)
 339 {
 340         struct evdev_client *client = file->private_data;
 341
 342         return fasync_helper(fd, file, on, &client->fasync);
 343 }
 344
 345 static void evdev_free(struct device *dev)
 346 {
 347         struct evdev *evdev = container_of(dev, struct evdev, dev);
 348
 349         input_put_device(evdev->handle.dev);
 350         kfree(evdev);
 351 }
 352
 353 /*
 354  * Grabs an event device (along with underlying input device).
 355  * This function is called with evdev->mutex taken.
 356  */
 357 static int evdev_grab(struct evdev *evdev, struct evdev_client *client)
 358 {
 359         int error;
 360
 361         if (evdev->grab)
 362                 return -EBUSY;
 363
 364         error = input_grab_device(&evdev->handle);
 365         if (error)
 366                 return error;
 367
 368         rcu_assign_pointer(evdev->grab, client);
 369
 370         return 0;
 371 }
 372
 373 static int evdev_ungrab(struct evdev *evdev, struct evdev_client *client)
 374 {
 375         struct evdev_client *grab = rcu_dereference_protected(evdev->grab,
 376                                         lockdep_is_held(&evdev->mutex));
 377
 378         if (grab != client)
 379                 return  -EINVAL;
 380
 381         rcu_assign_pointer(evdev->grab, NULL);
 382         synchronize_rcu();
 383         input_release_device(&evdev->handle);
 384
 385         return 0;
 386 }
 387
 388 static void evdev_attach_client(struct evdev *evdev,
 389                                 struct evdev_client *client)
 390 {
 391         spin_lock(&evdev->client_lock);
 392         list_add_tail_rcu(&client->node, &evdev->client_list);
 393         spin_unlock(&evdev->client_lock);
 394 }
 395
 396 static void evdev_detach_client(struct evdev *evdev,
 397                                 struct evdev_client *client)
 398 {
 399         spin_lock(&evdev->client_lock);
 400         list_del_rcu(&client->node);
 401         spin_unlock(&evdev->client_lock);
 402         synchronize_rcu();
 403 }
 404
 405 static int evdev_open_device(struct evdev *evdev)
 406 {
 407         int retval;
 408
 409         retval = mutex_lock_interruptible(&evdev->mutex);
 410         if (retval)
 411                 return retval;
 412
 413         if (!evdev->exist)
 414                 retval = -ENODEV;
 415         else if (!evdev->open++) {
 416                 retval = input_open_device(&evdev->handle);
 417                 if (retval)
 418                         evdev->open--;
 419         }
 420
 421         mutex_unlock(&evdev->mutex);
 422         return retval;
 423 }
 424
 425 static void evdev_close_device(struct evdev *evdev)
 426 {
 427         mutex_lock(&evdev->mutex);
 428
 429         if (evdev->exist && !--evdev->open)
 430                 input_close_device(&evdev->handle);
 431
 432         mutex_unlock(&evdev->mutex);
 433 }
 434
 435 /*
 436  * Wake up users waiting for IO so they can disconnect from
 437  * dead device.
 438  */
 439 static void evdev_hangup(struct evdev *evdev)
 440 {
 441         struct evdev_client *client;
 442
 443         spin_lock(&evdev->client_lock);
 444         list_for_each_entry(client, &evdev->client_list, node)
 445                 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
 446         spin_unlock(&evdev->client_lock);
 447
 448         wake_up_interruptible(&evdev->wait);
 449 }
 450
 451 static int evdev_release(struct inode *inode, struct file *file)
 452 {
 453         struct evdev_client *client = file->private_data;
 454         struct evdev *evdev = client->evdev;
 455         unsigned int i;
 456
 457         mutex_lock(&evdev->mutex);
 458
 459         if (evdev->exist && !client->revoked)
 460                 input_flush_device(&evdev->handle, file);
 461
 462         evdev_ungrab(evdev, client);
 463         mutex_unlock(&evdev->mutex);
 464
 465         evdev_detach_client(evdev, client);
 466
 467         for (i = 0; i < EV_CNT; ++i)
 468                 kfree(client->evmasks[i]);
 469
 470         kvfree(client);
 471
 472         evdev_close_device(evdev);
 473
 474         return 0;
 475 }
 476
 477 static unsigned int evdev_compute_buffer_size(struct input_dev *dev)
 478 {
 479         unsigned int n_events =
 480                 max(dev->hint_events_per_packet * EVDEV_BUF_PACKETS,
 481                     EVDEV_MIN_BUFFER_SIZE);
 482
 483         return roundup_pow_of_two(n_events);
 484 }
 485
 486 static int evdev_open(struct inode *inode, struct file *file)
 487 {
 488         struct evdev *evdev = container_of(inode->i_cdev, struct evdev, cdev);
 489         unsigned int bufsize = evdev_compute_buffer_size(evdev->handle.dev);
 490         unsigned int size = sizeof(struct evdev_client) +
 491                                         bufsize * sizeof(struct input_event);
 492         struct evdev_client *client;
 493         int error;
 494
 495         client = kzalloc(size, GFP_KERNEL | __GFP_NOWARN);
 496         if (!client)
 497                 client = vzalloc(size);
 498         if (!client)
 499                 return -ENOMEM;
 500
 501         client->bufsize = bufsize;
 502         spin_lock_init(&client->buffer_lock);
 503         client->evdev = evdev;
 504         evdev_attach_client(evdev, client);
 505
 506         error = evdev_open_device(evdev);
 507         if (error)
 508                 goto err_free_client;
 509
 510         file->private_data = client;
 511         nonseekable_open(inode, file);
 512
 513         return 0;
 514
 515  err_free_client:
 516         evdev_detach_client(evdev, client);
 517         kvfree(client);
 518         return error;
 519 }
 520
 521 static ssize_t evdev_write(struct file *file, const char __user *buffer,
 522                            size_t count, loff_t *ppos)
 523 {
 524         struct evdev_client *client = file->private_data;
 525         struct evdev *evdev = client->evdev;
 526         struct input_event event;
 527         int retval = 0;
 528
 529         if (count != 0 && count < input_event_size())
 530                 return -EINVAL;
 531
 532         retval = mutex_lock_interruptible(&evdev->mutex);
 533         if (retval)
 534                 return retval;
 535
 536         if (!evdev->exist || client->revoked) {
 537                 retval = -ENODEV;
 538                 goto out;
 539         }
 540
 541         while (retval + input_event_size() <= count) {
 542
 543                 if (input_event_from_user(buffer + retval, &event)) {
 544                         retval = -EFAULT;
 545                         goto out;
 546                 }
 547                 retval += input_event_size();
 548
 549                 input_inject_event(&evdev->handle,
 550                                    event.type, event.code, event.value);
 551         }
 552
 553  out:
 554         mutex_unlock(&evdev->mutex);
 555         return retval;
 556 }
 557
 558 static int evdev_fetch_next_event(struct evdev_client *client,
 559                                   struct input_event *event)
 560 {
 561         int have_event;
 562
 563         spin_lock_irq(&client->buffer_lock);
 564
 565         have_event = client->packet_head != client->tail;
 566         if (have_event) {
 567                 *event = client->buffer[client->tail++];
 568                 client->tail &= client->bufsize - 1;
 569         }
 570
 571         spin_unlock_irq(&client->buffer_lock);
 572
 573         return have_event;
 574 }
 575
 576 static ssize_t evdev_read(struct file *file, char __user *buffer,
 577                           size_t count, loff_t *ppos)
 578 {
 579         struct evdev_client *client = file->private_data;
 580         struct evdev *evdev = client->evdev;
 581         struct input_event event;
 582         size_t read = 0;
 583         int error;
 584
 585         if (count != 0 && count < input_event_size())
 586                 return -EINVAL;
 587
 588         for (;;) {
 589                 if (!evdev->exist || client->revoked)
 590                         return -ENODEV;
 591
 592                 if (client->packet_head == client->tail &&
 593                     (file->f_flags & O_NONBLOCK))
 594                         return -EAGAIN;
 595
 596                 /*
 597                  * count == 0 is special - no IO is done but we check
 598                  * for error conditions (see above).
 599                  */
 600                 if (count == 0)
 601                         break;
 602
 603                 while (read + input_event_size() <= count &&
 604                        evdev_fetch_next_event(client, &event)) {
 605
 606                         if (input_event_to_user(buffer + read, &event))
 607                                 return -EFAULT;
 608
 609                         read += input_event_size();
 610                 }
 611
 612                 if (read)
 613                         break;
 614
 615                 if (!(file->f_flags & O_NONBLOCK)) {
 616                         error = wait_event_interruptible(evdev->wait,
 617                                         client->packet_head != client->tail ||
 618                                         !evdev->exist || client->revoked);
 619                         if (error)
 620                                 return error;
 621                 }
 622         }
 623
 624         return read;
 625 }
 626
 627 /* No kernel lock - fine */
 628 static unsigned int evdev_poll(struct file *file, poll_table *wait)
 629 {
 630         struct evdev_client *client = file->private_data;
 631         struct evdev *evdev = client->evdev;
 632         unsigned int mask;
 633
 634         poll_wait(file, &evdev->wait, wait);
 635
 636         if (evdev->exist && !client->revoked)
 637                 mask = POLLOUT | POLLWRNORM;
 638         else
 639                 mask = POLLHUP | POLLERR;
 640
 641         if (client->packet_head != client->tail)
 642                 mask |= POLLIN | POLLRDNORM;
 643
 644         return mask;
 645 }
 646
 647 #ifdef CONFIG_COMPAT
 648
 649 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
 650 #define BITS_TO_LONGS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1)
 651
 652 #ifdef __BIG_ENDIAN
 653 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
 654                         unsigned int maxlen, void __user *p, int compat)
 655 {
 656         int len, i;
 657
 658         if (compat) {
 659                 len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t);
 660                 if (len > maxlen)
 661                         len = maxlen;
 662
 663                 for (i = 0; i < len / sizeof(compat_long_t); i++)
 664                         if (copy_to_user((compat_long_t __user *) p + i,
 665                                          (compat_long_t *) bits +
 666                                                 i + 1 - ((i % 2) << 1),
 667                                          sizeof(compat_long_t)))
 668                                 return -EFAULT;
 669         } else {
 670                 len = BITS_TO_LONGS(maxbit) * sizeof(long);
 671                 if (len > maxlen)
 672                         len = maxlen;
 673
 674                 if (copy_to_user(p, bits, len))
 675                         return -EFAULT;
 676         }
 677
 678         return len;
 679 }
 680
 681 static int bits_from_user(unsigned long *bits, unsigned int maxbit,
 682                           unsigned int maxlen, const void __user *p, int compat)
 683 {
 684         int len, i;
 685
 686         if (compat) {
 687                 if (maxlen % sizeof(compat_long_t))
 688                         return -EINVAL;
 689
 690                 len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t);
 691                 if (len > maxlen)
 692                         len = maxlen;
 693
 694                 for (i = 0; i < len / sizeof(compat_long_t); i++)
 695                         if (copy_from_user((compat_long_t *) bits +
 696                                                 i + 1 - ((i % 2) << 1),
 697                                            (compat_long_t __user *) p + i,
 698                                            sizeof(compat_long_t)))
 699                                 return -EFAULT;
 700                 if (i % 2)
 701                         *((compat_long_t *) bits + i - 1) = 0;
 702
 703         } else {
 704                 if (maxlen % sizeof(long))
 705                         return -EINVAL;
 706
 707                 len = BITS_TO_LONGS(maxbit) * sizeof(long);
 708                 if (len > maxlen)
 709                         len = maxlen;
 710
 711                 if (copy_from_user(bits, p, len))
 712                         return -EFAULT;
 713         }
 714
 715         return len;
 716 }
 717
 718 #else
 719
 720 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
 721                         unsigned int maxlen, void __user *p, int compat)
 722 {
 723         int len = compat ?
 724                         BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t) :
 725                         BITS_TO_LONGS(maxbit) * sizeof(long);
 726
 727         if (len > maxlen)
 728                 len = maxlen;
 729
 730         return copy_to_user(p, bits, len) ? -EFAULT : len;
 731 }
 732
 733 static int bits_from_user(unsigned long *bits, unsigned int maxbit,
 734                           unsigned int maxlen, const void __user *p, int compat)
 735 {
 736         size_t chunk_size = compat ? sizeof(compat_long_t) : sizeof(long);
 737         int len;
 738
 739         if (maxlen % chunk_size)
 740                 return -EINVAL;
 741
 742         len = compat ? BITS_TO_LONGS_COMPAT(maxbit) : BITS_TO_LONGS(maxbit);
 743         len *= chunk_size;
 744         if (len > maxlen)
 745                 len = maxlen;
 746
 747         return copy_from_user(bits, p, len) ? -EFAULT : len;
 748 }
 749
 750 #endif /* __BIG_ENDIAN */
 751
 752 #else
 753
 754 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
 755                         unsigned int maxlen, void __user *p, int compat)
 756 {
 757         int len = BITS_TO_LONGS(maxbit) * sizeof(long);
 758
 759         if (len > maxlen)
 760                 len = maxlen;
 761
 762         return copy_to_user(p, bits, len) ? -EFAULT : len;
 763 }
 764
 765 static int bits_from_user(unsigned long *bits, unsigned int maxbit,
 766                           unsigned int maxlen, const void __user *p, int compat)
 767 {
 768         int len;
 769
 770         if (maxlen % sizeof(long))
 771                 return -EINVAL;
 772
 773         len = BITS_TO_LONGS(maxbit) * sizeof(long);
 774         if (len > maxlen)
 775                 len = maxlen;
 776
 777         return copy_from_user(bits, p, len) ? -EFAULT : len;
 778 }
 779
 780 #endif /* CONFIG_COMPAT */
 781
 782 static int str_to_user(const char *str, unsigned int maxlen, void __user *p)
 783 {
 784         int len;
 785
 786         if (!str)
 787                 return -ENOENT;
 788
 789         len = strlen(str) + 1;
 790         if (len > maxlen)
 791                 len = maxlen;
 792
 793         return copy_to_user(p, str, len) ? -EFAULT : len;
 794 }
 795
 796 static int handle_eviocgbit(struct input_dev *dev,
 797                             unsigned int type, unsigned int size,
 798                             void __user *p, int compat_mode)
 799 {
 800         unsigned long *bits;
 801         int len;
 802
 803         switch (type) {
 804
 805         case      0: bits = dev->evbit;  len = EV_MAX;  break;
 806         case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
 807         case EV_REL: bits = dev->relbit; len = REL_MAX; break;
 808         case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
 809         case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break;
 810         case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
 811         case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
 812         case EV_FF:  bits = dev->ffbit;  len = FF_MAX;  break;
 813         case EV_SW:  bits = dev->swbit;  len = SW_MAX;  break;
 814         default: return -EINVAL;
 815         }
 816
 817         return bits_to_user(bits, len, size, p, compat_mode);
 818 }
 819
 820 static int evdev_handle_get_keycode(struct input_dev *dev, void __user *p)
 821 {
 822         struct input_keymap_entry ke = {
 823                 .len    = sizeof(unsigned int),
 824                 .flags  = 0,
 825         };
 826         int __user *ip = (int __user *)p;
 827         int error;
 828
 829         /* legacy case */
 830         if (copy_from_user(ke.scancode, p, sizeof(unsigned int)))
 831                 return -EFAULT;
 832
 833         error = input_get_keycode(dev, &ke);
 834         if (error)
 835                 return error;
 836
 837         if (put_user(ke.keycode, ip + 1))
 838                 return -EFAULT;
 839
 840         return 0;
 841 }
 842
 843 static int evdev_handle_get_keycode_v2(struct input_dev *dev, void __user *p)
 844 {
 845         struct input_keymap_entry ke;
 846         int error;
 847
 848         if (copy_from_user(&ke, p, sizeof(ke)))
 849                 return -EFAULT;
 850
 851         error = input_get_keycode(dev, &ke);
 852         if (error)
 853                 return error;
 854
 855         if (copy_to_user(p, &ke, sizeof(ke)))
 856                 return -EFAULT;
 857
 858         return 0;
 859 }
 860
 861 static int evdev_handle_set_keycode(struct input_dev *dev, void __user *p)
 862 {
 863         struct input_keymap_entry ke = {
 864                 .len    = sizeof(unsigned int),
 865                 .flags  = 0,
 866         };
 867         int __user *ip = (int __user *)p;
 868
 869         if (copy_from_user(ke.scancode, p, sizeof(unsigned int)))
 870                 return -EFAULT;
 871
 872         if (get_user(ke.keycode, ip + 1))
 873                 return -EFAULT;
 874
 875         return input_set_keycode(dev, &ke);
 876 }
 877
 878 static int evdev_handle_set_keycode_v2(struct input_dev *dev, void __user *p)
 879 {
 880         struct input_keymap_entry ke;
 881
 882         if (copy_from_user(&ke, p, sizeof(ke)))
 883                 return -EFAULT;
 884
 885         if (ke.len > sizeof(ke.scancode))
 886                 return -EINVAL;
 887
 888         return input_set_keycode(dev, &ke);
 889 }
 890
 891 /*
 892  * If we transfer state to the user, we should flush all pending events
 893  * of the same type from the client's queue. Otherwise, they might end up
 894  * with duplicate events, which can screw up client's state tracking.
 895  * If bits_to_user fails after flushing the queue, we queue a SYN_DROPPED
 896  * event so user-space will notice missing events.
 897  *
 898  * LOCKING:
 899  * We need to take event_lock before buffer_lock to avoid dead-locks. But we
 900  * need the even_lock only to guarantee consistent state. We can safely release
 901  * it while flushing the queue. This allows input-core to handle filters while
 902  * we flush the queue.
 903  */
 904 static int evdev_handle_get_val(struct evdev_client *client,
 905                                 struct input_dev *dev, unsigned int type,
 906                                 unsigned long *bits, unsigned int maxbit,
 907                                 unsigned int maxlen, void __user *p,
 908                                 int compat)
 909 {
 910         int ret;
 911         unsigned long *mem;
 912         size_t len;
 913
 914         len = BITS_TO_LONGS(maxbit) * sizeof(unsigned long);
 915         mem = kmalloc(len, GFP_KERNEL);
 916         if (!mem)
 917                 return -ENOMEM;
 918
 919         spin_lock_irq(&dev->event_lock);
 920         spin_lock(&client->buffer_lock);
 921
 922         memcpy(mem, bits, len);
 923
 924         spin_unlock(&dev->event_lock);
 925
 926         __evdev_flush_queue(client, type);
 927
 928         spin_unlock_irq(&client->buffer_lock);
 929
 930         ret = bits_to_user(mem, maxbit, maxlen, p, compat);
 931         if (ret < 0)
 932                 evdev_queue_syn_dropped(client);
 933
 934         kfree(mem);
 935
 936         return ret;
 937 }
 938
 939 static int evdev_handle_mt_request(struct input_dev *dev,
 940                                    unsigned int size,
 941                                    int __user *ip)
 942 {
 943         const struct input_mt *mt = dev->mt;
 944         unsigned int code;
 945         int max_slots;
 946         int i;
 947
 948         if (get_user(code, &ip[0]))
 949                 return -EFAULT;
 950         if (!mt || !input_is_mt_value(code))
 951                 return -EINVAL;
 952
 953         max_slots = (size - sizeof(__u32)) / sizeof(__s32);
 954         for (i = 0; i < mt->num_slots && i < max_slots; i++) {
 955                 int value = input_mt_get_value(&mt->slots[i], code);
 956                 if (put_user(value, &ip[1 + i]))
 957                         return -EFAULT;
 958         }
 959
 960         return 0;
 961 }
 962
 963 static int evdev_revoke(struct evdev *evdev, struct evdev_client *client,
 964                         struct file *file)
 965 {
 966         client->revoked = true;
 967         evdev_ungrab(evdev, client);
 968         input_flush_device(&evdev->handle, file);
 969         wake_up_interruptible(&evdev->wait);
 970
 971         return 0;
 972 }
 973
 974 /* must be called with evdev-mutex held */
 975 static int evdev_set_mask(struct evdev_client *client,
 976                           unsigned int type,
 977                           const void __user *codes,
 978                           u32 codes_size,
 979                           int compat)
 980 {
 981         unsigned long flags, *mask, *oldmask;
 982         size_t cnt;
 983         int error;
 984
 985         /* we allow unknown types and 'codes_size > size' for forward-compat */
 986         cnt = evdev_get_mask_cnt(type);
 987         if (!cnt)
 988                 return 0;
 989
 990         mask = kcalloc(sizeof(unsigned long), BITS_TO_LONGS(cnt), GFP_KERNEL);
 991         if (!mask)
 992                 return -ENOMEM;
 993
 994         error = bits_from_user(mask, cnt - 1, codes_size, codes, compat);
 995         if (error < 0) {
 996                 kfree(mask);
 997                 return error;
 998         }
 999
1000         spin_lock_irqsave(&client->buffer_lock, flags);
1001         oldmask = client->evmasks[type];
1002         client->evmasks[type] = mask;
1003         spin_unlock_irqrestore(&client->buffer_lock, flags);
1004
1005         kfree(oldmask);
1006
1007         return 0;
1008 }
1009
1010 /* must be called with evdev-mutex held */
1011 static int evdev_get_mask(struct evdev_client *client,
1012                           unsigned int type,
1013                           void __user *codes,
1014                           u32 codes_size,
1015                           int compat)
1016 {
1017         unsigned long *mask;
1018         size_t cnt, size, xfer_size;
1019         int i;
1020         int error;
1021
1022         /* we allow unknown types and 'codes_size > size' for forward-compat */
1023         cnt = evdev_get_mask_cnt(type);
1024         size = sizeof(unsigned long) * BITS_TO_LONGS(cnt);
1025         xfer_size = min_t(size_t, codes_size, size);
1026
1027         if (cnt > 0) {
1028                 mask = client->evmasks[type];
1029                 if (mask) {
1030                         error = bits_to_user(mask, cnt - 1,
1031                                              xfer_size, codes, compat);
1032                         if (error < 0)
1033                                 return error;
1034                 } else {
1035                         /* fake mask with all bits set */
1036                         for (i = 0; i < xfer_size; i++)
1037                                 if (put_user(0xffU, (u8 __user *)codes + i))
1038                                         return -EFAULT;
1039                 }
1040         }
1041
1042         if (xfer_size < codes_size)
1043                 if (clear_user(codes + xfer_size, codes_size - xfer_size))
1044                         return -EFAULT;
1045
1046         return 0;
1047 }
1048
1049 static long evdev_do_ioctl(struct file *file, unsigned int cmd,
1050                            void __user *p, int compat_mode)
1051 {
1052         struct evdev_client *client = file->private_data;
1053         struct evdev *evdev = client->evdev;
1054         struct input_dev *dev = evdev->handle.dev;
1055         struct input_absinfo abs;
1056         struct input_mask mask;
1057         struct ff_effect effect;
1058         int __user *ip = (int __user *)p;
1059         unsigned int i, t, u, v;
1060         unsigned int size;
1061         int error;
1062
1063         /* First we check for fixed-length commands */
1064         switch (cmd) {
1065
1066         case EVIOCGVERSION:
1067                 return put_user(EV_VERSION, ip);
1068
1069         case EVIOCGID:
1070                 if (copy_to_user(p, &dev->id, sizeof(struct input_id)))
1071                         return -EFAULT;
1072                 return 0;
1073
1074         case EVIOCGREP:
1075                 if (!test_bit(EV_REP, dev->evbit))
1076                         return -ENOSYS;
1077                 if (put_user(dev->rep[REP_DELAY], ip))
1078                         return -EFAULT;
1079                 if (put_user(dev->rep[REP_PERIOD], ip + 1))
1080                         return -EFAULT;
1081                 return 0;
1082
1083         case EVIOCSREP:
1084                 if (!test_bit(EV_REP, dev->evbit))
1085                         return -ENOSYS;
1086                 if (get_user(u, ip))
1087                         return -EFAULT;
1088                 if (get_user(v, ip + 1))
1089                         return -EFAULT;
1090
1091                 input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u);
1092                 input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v);
1093
1094                 return 0;
1095
1096         case EVIOCRMFF:
1097                 return input_ff_erase(dev, (int)(unsigned long) p, file);
1098
1099         case EVIOCGEFFECTS:
1100                 i = test_bit(EV_FF, dev->evbit) ?
1101                                 dev->ff->max_effects : 0;
1102                 if (put_user(i, ip))
1103                         return -EFAULT;
1104                 return 0;
1105
1106         case EVIOCGRAB:
1107                 if (p)
1108                         return evdev_grab(evdev, client);
1109                 else
1110                         return evdev_ungrab(evdev, client);
1111
1112         case EVIOCREVOKE:
1113                 if (p)
1114                         return -EINVAL;
1115                 else
1116                         return evdev_revoke(evdev, client, file);
1117
1118         case EVIOCGMASK: {
1119                 void __user *codes_ptr;
1120
1121                 if (copy_from_user(&mask, p, sizeof(mask)))
1122                         return -EFAULT;
1123
1124                 codes_ptr = (void __user *)(unsigned long)mask.codes_ptr;
1125                 return evdev_get_mask(client,
1126                                       mask.type, codes_ptr, mask.codes_size,
1127                                       compat_mode);
1128         }
1129
1130         case EVIOCSMASK: {
1131                 const void __user *codes_ptr;
1132
1133                 if (copy_from_user(&mask, p, sizeof(mask)))
1134                         return -EFAULT;
1135
1136                 codes_ptr = (const void __user *)(unsigned long)mask.codes_ptr;
1137                 return evdev_set_mask(client,
1138                                       mask.type, codes_ptr, mask.codes_size,
1139                                       compat_mode);
1140         }
1141
1142         case EVIOCSCLOCKID:
1143                 if (copy_from_user(&i, p, sizeof(unsigned int)))
1144                         return -EFAULT;
1145
1146                 return evdev_set_clk_type(client, i);
1147
1148         case EVIOCGKEYCODE:
1149                 return evdev_handle_get_keycode(dev, p);
1150
1151         case EVIOCSKEYCODE:
1152                 return evdev_handle_set_keycode(dev, p);
1153
1154         case EVIOCGKEYCODE_V2:
1155                 return evdev_handle_get_keycode_v2(dev, p);
1156
1157         case EVIOCSKEYCODE_V2:
1158                 return evdev_handle_set_keycode_v2(dev, p);
1159         }
1160
1161         size = _IOC_SIZE(cmd);
1162
1163         /* Now check variable-length commands */
1164 #define EVIOC_MASK_SIZE(nr)     ((nr) & ~(_IOC_SIZEMASK << _IOC_SIZESHIFT))
1165         switch (EVIOC_MASK_SIZE(cmd)) {
1166
1167         case EVIOCGPROP(0):
1168                 return bits_to_user(dev->propbit, INPUT_PROP_MAX,
1169                                     size, p, compat_mode);
1170
1171         case EVIOCGMTSLOTS(0):
1172                 return evdev_handle_mt_request(dev, size, ip);
1173
1174         case EVIOCGKEY(0):
1175                 return evdev_handle_get_val(client, dev, EV_KEY, dev->key,
1176                                             KEY_MAX, size, p, compat_mode);
1177
1178         case EVIOCGLED(0):
1179                 return evdev_handle_get_val(client, dev, EV_LED, dev->led,
1180                                             LED_MAX, size, p, compat_mode);
1181
1182         case EVIOCGSND(0):
1183                 return evdev_handle_get_val(client, dev, EV_SND, dev->snd,
1184                                             SND_MAX, size, p, compat_mode);
1185
1186         case EVIOCGSW(0):
1187                 return evdev_handle_get_val(client, dev, EV_SW, dev->sw,
1188                                             SW_MAX, size, p, compat_mode);
1189
1190         case EVIOCGNAME(0):
1191                 return str_to_user(dev->name, size, p);
1192
1193         case EVIOCGPHYS(0):
1194                 return str_to_user(dev->phys, size, p);
1195
1196         case EVIOCGUNIQ(0):
1197                 return str_to_user(dev->uniq, size, p);
1198
1199         case EVIOC_MASK_SIZE(EVIOCSFF):
1200                 if (input_ff_effect_from_user(p, size, &effect))
1201                         return -EFAULT;
1202
1203                 error = input_ff_upload(dev, &effect, file);
1204                 if (error)
1205                         return error;
1206
1207                 if (put_user(effect.id, &(((struct ff_effect __user *)p)->id)))
1208                         return -EFAULT;
1209
1210                 return 0;
1211         }
1212
1213         /* Multi-number variable-length handlers */
1214         if (_IOC_TYPE(cmd) != 'E')
1215                 return -EINVAL;
1216
1217         if (_IOC_DIR(cmd) == _IOC_READ) {
1218
1219                 if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0, 0)))
1220                         return handle_eviocgbit(dev,
1221                                                 _IOC_NR(cmd) & EV_MAX, size,
1222                                                 p, compat_mode);
1223
1224                 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
1225
1226                         if (!dev->absinfo)
1227                                 return -EINVAL;
1228
1229                         t = _IOC_NR(cmd) & ABS_MAX;
1230                         abs = dev->absinfo[t];
1231
1232                         if (copy_to_user(p, &abs, min_t(size_t,
1233                                         size, sizeof(struct input_absinfo))))
1234                                 return -EFAULT;
1235
1236                         return 0;
1237                 }
1238         }
1239
1240         if (_IOC_DIR(cmd) == _IOC_WRITE) {
1241
1242                 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
1243
1244                         if (!dev->absinfo)
1245                                 return -EINVAL;
1246
1247                         t = _IOC_NR(cmd) & ABS_MAX;
1248
1249                         if (copy_from_user(&abs, p, min_t(size_t,
1250                                         size, sizeof(struct input_absinfo))))
1251                                 return -EFAULT;
1252
1253                         if (size < sizeof(struct input_absinfo))
1254                                 abs.resolution = 0;
1255
1256                         /* We can't change number of reserved MT slots */
1257                         if (t == ABS_MT_SLOT)
1258                                 return -EINVAL;
1259
1260                         /*
1261                          * Take event lock to ensure that we are not
1262                          * changing device parameters in the middle
1263                          * of event.
1264                          */
1265                         spin_lock_irq(&dev->event_lock);
1266                         dev->absinfo[t] = abs;
1267                         spin_unlock_irq(&dev->event_lock);
1268
1269                         return 0;
1270                 }
1271         }
1272
1273         return -EINVAL;
1274 }
1275
1276 static long evdev_ioctl_handler(struct file *file, unsigned int cmd,
1277                                 void __user *p, int compat_mode)
1278 {
1279         struct evdev_client *client = file->private_data;
1280         struct evdev *evdev = client->evdev;
1281         int retval;
1282
1283         retval = mutex_lock_interruptible(&evdev->mutex);
1284         if (retval)
1285                 return retval;
1286
1287         if (!evdev->exist || client->revoked) {
1288                 retval = -ENODEV;
1289                 goto out;
1290         }
1291
1292         retval = evdev_do_ioctl(file, cmd, p, compat_mode);
1293
1294  out:
1295         mutex_unlock(&evdev->mutex);
1296         return retval;
1297 }
1298
1299 static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1300 {
1301         return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0);
1302 }
1303
1304 #ifdef CONFIG_COMPAT
1305 static long evdev_ioctl_compat(struct file *file,
1306                                 unsigned int cmd, unsigned long arg)
1307 {
1308         return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1);
1309 }
1310 #endif
1311
1312 static const struct file_operations evdev_fops = {
1313         .owner          = THIS_MODULE,
1314         .read           = evdev_read,
1315         .write          = evdev_write,
1316         .poll           = evdev_poll,
1317         .open           = evdev_open,
1318         .release        = evdev_release,
1319         .unlocked_ioctl = evdev_ioctl,
1320 #ifdef CONFIG_COMPAT
1321         .compat_ioctl   = evdev_ioctl_compat,
1322 #endif
1323         .fasync         = evdev_fasync,
1324         .llseek         = no_llseek,
1325 };
1326
1327 /*
1328  * Mark device non-existent. This disables writes, ioctls and
1329  * prevents new users from opening the device. Already posted
1330  * blocking reads will stay, however new ones will fail.
1331  */
1332 static void evdev_mark_dead(struct evdev *evdev)
1333 {
1334         mutex_lock(&evdev->mutex);
1335         evdev->exist = false;
1336         mutex_unlock(&evdev->mutex);
1337 }
1338
1339 static void evdev_cleanup(struct evdev *evdev)
1340 {
1341         struct input_handle *handle = &evdev->handle;
1342
1343         evdev_mark_dead(evdev);
1344         evdev_hangup(evdev);
1345
1346         cdev_del(&evdev->cdev);
1347
1348         /* evdev is marked dead so no one else accesses evdev->open */
1349         if (evdev->open) {
1350                 input_flush_device(handle, NULL);
1351                 input_close_device(handle);
1352         }
1353 }
1354
1355 /*
1356  * Create new evdev device. Note that input core serializes calls
1357  * to connect and disconnect.
1358  */
1359 static int evdev_connect(struct input_handler *handler, struct input_dev *dev,
1360                          const struct input_device_id *id)
1361 {
1362         struct evdev *evdev;
1363         int minor;
1364         int dev_no;
1365         int error;
1366
1367         minor = input_get_new_minor(EVDEV_MINOR_BASE, EVDEV_MINORS, true);
1368         if (minor < 0) {
1369                 error = minor;
1370                 pr_err("failed to reserve new minor: %d\n", error);
1371                 return error;
1372         }
1373
1374         evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL);
1375         if (!evdev) {
1376                 error = -ENOMEM;
1377                 goto err_free_minor;
1378         }
1379
1380         INIT_LIST_HEAD(&evdev->client_list);
1381         spin_lock_init(&evdev->client_lock);
1382         mutex_init(&evdev->mutex);
1383         init_waitqueue_head(&evdev->wait);
1384         evdev->exist = true;
1385
1386         dev_no = minor;
1387         /* Normalize device number if it falls into legacy range */
1388         if (dev_no < EVDEV_MINOR_BASE + EVDEV_MINORS)
1389                 dev_no -= EVDEV_MINOR_BASE;
1390         dev_set_name(&evdev->dev, "event%d", dev_no);
1391
1392         evdev->handle.dev = input_get_device(dev);
1393         evdev->handle.name = dev_name(&evdev->dev);
1394         evdev->handle.handler = handler;
1395         evdev->handle.private = evdev;
1396
1397         evdev->dev.devt = MKDEV(INPUT_MAJOR, minor);
1398         evdev->dev.class = &input_class;
1399         evdev->dev.parent = &dev->dev;
1400         evdev->dev.release = evdev_free;
1401         device_initialize(&evdev->dev);
1402
1403         error = input_register_handle(&evdev->handle);
1404         if (error)
1405                 goto err_free_evdev;
1406
1407         cdev_init(&evdev->cdev, &evdev_fops);
1408         evdev->cdev.kobj.parent = &evdev->dev.kobj;
1409         error = cdev_add(&evdev->cdev, evdev->dev.devt, 1);
1410         if (error)
1411                 goto err_unregister_handle;
1412
1413         error = device_add(&evdev->dev);
1414         if (error)
1415                 goto err_cleanup_evdev;
1416
1417         return 0;
1418
1419  err_cleanup_evdev:
1420         evdev_cleanup(evdev);
1421  err_unregister_handle:
1422         input_unregister_handle(&evdev->handle);
1423  err_free_evdev:
1424         put_device(&evdev->dev);
1425  err_free_minor:
1426         input_free_minor(minor);
1427         return error;
1428 }
1429
1430 static void evdev_disconnect(struct input_handle *handle)
1431 {
1432         struct evdev *evdev = handle->private;
1433
1434         device_del(&evdev->dev);
1435         evdev_cleanup(evdev);
1436         input_free_minor(MINOR(evdev->dev.devt));
1437         input_unregister_handle(handle);
1438         put_device(&evdev->dev);
1439 }
1440
1441 static const struct input_device_id evdev_ids[] = {
1442         { .driver_info = 1 },   /* Matches all devices */
1443         { },                    /* Terminating zero entry */
1444 };
1445
1446 MODULE_DEVICE_TABLE(input, evdev_ids);
1447
1448 static struct input_handler evdev_handler = {
1449         .event          = evdev_event,
1450         .events         = evdev_events,
1451         .connect        = evdev_connect,
1452         .disconnect     = evdev_disconnect,
1453         .legacy_minors  = true,
1454         .minor          = EVDEV_MINOR_BASE,
1455         .name           = "evdev",
1456         .id_table       = evdev_ids,
1457 };
1458
1459 static int __init evdev_init(void)
1460 {
1461         return input_register_handler(&evdev_handler);
1462 }
1463
1464 static void __exit evdev_exit(void)
1465 {
1466         input_unregister_handler(&evdev_handler);
1467 }
1468
1469 module_init(evdev_init);
1470 module_exit(evdev_exit);
1471
1472 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
1473 MODULE_DESCRIPTION("Input driver event char devices");
1474 MODULE_LICENSE("GPL");