drivers/input/joydev.c

   1 /*
   2  * Joystick device driver for the input driver suite.
   3  *
   4  * Copyright (c) 1999-2002 Vojtech Pavlik
   5  * Copyright (c) 1999 Colin Van Dyke
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  */
  12
  13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  14
  15 #include <asm/io.h>
  16 #include <linux/delay.h>
  17 #include <linux/errno.h>
  18 #include <linux/joystick.h>
  19 #include <linux/input.h>
  20 #include <linux/kernel.h>
  21 #include <linux/major.h>
  22 #include <linux/sched.h>
  23 #include <linux/slab.h>
  24 #include <linux/mm.h>
  25 #include <linux/module.h>
  26 #include <linux/poll.h>
  27 #include <linux/init.h>
  28 #include <linux/device.h>
  29 #include <linux/cdev.h>
  30
  31 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
  32 MODULE_DESCRIPTION("Joystick device interfaces");
  33 MODULE_SUPPORTED_DEVICE("input/js");
  34 MODULE_LICENSE("GPL");
  35
  36 #define JOYDEV_MINOR_BASE       0
  37 #define JOYDEV_MINORS           16
  38 #define JOYDEV_BUFFER_SIZE      64
  39
  40 struct joydev {
  41         int open;
  42         struct input_handle handle;
  43         wait_queue_head_t wait;
  44         struct list_head client_list;
  45         spinlock_t client_lock; /* protects client_list */
  46         struct mutex mutex;
  47         struct device dev;
  48         struct cdev cdev;
  49         bool exist;
  50
  51         struct js_corr corr[ABS_CNT];
  52         struct JS_DATA_SAVE_TYPE glue;
  53         int nabs;
  54         int nkey;
  55         __u16 keymap[KEY_MAX - BTN_MISC + 1];
  56         __u16 keypam[KEY_MAX - BTN_MISC + 1];
  57         __u8 absmap[ABS_CNT];
  58         __u8 abspam[ABS_CNT];
  59         __s16 abs[ABS_CNT];
  60 };
  61
  62 struct joydev_client {
  63         struct js_event buffer[JOYDEV_BUFFER_SIZE];
  64         int head;
  65         int tail;
  66         int startup;
  67         spinlock_t buffer_lock; /* protects access to buffer, head and tail */
  68         struct fasync_struct *fasync;
  69         struct joydev *joydev;
  70         struct list_head node;
  71 };
  72
  73 static int joydev_correct(int value, struct js_corr *corr)
  74 {
  75         switch (corr->type) {
  76
  77         case JS_CORR_NONE:
  78                 break;
  79
  80         case JS_CORR_BROKEN:
  81                 value = value > corr->coef[0] ? (value < corr->coef[1] ? 0 :
  82                         ((corr->coef[3] * (value - corr->coef[1])) >> 14)) :
  83                         ((corr->coef[2] * (value - corr->coef[0])) >> 14);
  84                 break;
  85
  86         default:
  87                 return 0;
  88         }
  89
  90         return value < -32767 ? -32767 : (value > 32767 ? 32767 : value);
  91 }
  92
  93 static void joydev_pass_event(struct joydev_client *client,
  94                               struct js_event *event)
  95 {
  96         struct joydev *joydev = client->joydev;
  97
  98         /*
  99          * IRQs already disabled, just acquire the lock
 100          */
 101         spin_lock(&client->buffer_lock);
 102
 103         client->buffer[client->head] = *event;
 104
 105         if (client->startup == joydev->nabs + joydev->nkey) {
 106                 client->head++;
 107                 client->head &= JOYDEV_BUFFER_SIZE - 1;
 108                 if (client->tail == client->head)
 109                         client->startup = 0;
 110         }
 111
 112         spin_unlock(&client->buffer_lock);
 113
 114         kill_fasync(&client->fasync, SIGIO, POLL_IN);
 115 }
 116
 117 static void joydev_event(struct input_handle *handle,
 118                          unsigned int type, unsigned int code, int value)
 119 {
 120         struct joydev *joydev = handle->private;
 121         struct joydev_client *client;
 122         struct js_event event;
 123
 124         switch (type) {
 125
 126         case EV_KEY:
 127                 if (code < BTN_MISC || value == 2)
 128                         return;
 129                 event.type = JS_EVENT_BUTTON;
 130                 event.number = joydev->keymap[code - BTN_MISC];
 131                 event.value = value;
 132                 break;
 133
 134         case EV_ABS:
 135                 event.type = JS_EVENT_AXIS;
 136                 event.number = joydev->absmap[code];
 137                 event.value = joydev_correct(value,
 138                                         &joydev->corr[event.number]);
 139                 if (event.value == joydev->abs[event.number])
 140                         return;
 141                 joydev->abs[event.number] = event.value;
 142                 break;
 143
 144         default:
 145                 return;
 146         }
 147
 148         event.time = jiffies_to_msecs(jiffies);
 149
 150         rcu_read_lock();
 151         list_for_each_entry_rcu(client, &joydev->client_list, node)
 152                 joydev_pass_event(client, &event);
 153         rcu_read_unlock();
 154
 155         wake_up_interruptible(&joydev->wait);
 156 }
 157
 158 static int joydev_fasync(int fd, struct file *file, int on)
 159 {
 160         struct joydev_client *client = file->private_data;
 161
 162         return fasync_helper(fd, file, on, &client->fasync);
 163 }
 164
 165 static void joydev_free(struct device *dev)
 166 {
 167         struct joydev *joydev = container_of(dev, struct joydev, dev);
 168
 169         input_put_device(joydev->handle.dev);
 170         kfree(joydev);
 171 }
 172
 173 static void joydev_attach_client(struct joydev *joydev,
 174                                  struct joydev_client *client)
 175 {
 176         spin_lock(&joydev->client_lock);
 177         list_add_tail_rcu(&client->node, &joydev->client_list);
 178         spin_unlock(&joydev->client_lock);
 179 }
 180
 181 static void joydev_detach_client(struct joydev *joydev,
 182                                  struct joydev_client *client)
 183 {
 184         spin_lock(&joydev->client_lock);
 185         list_del_rcu(&client->node);
 186         spin_unlock(&joydev->client_lock);
 187         synchronize_rcu();
 188 }
 189
 190 static int joydev_open_device(struct joydev *joydev)
 191 {
 192         int retval;
 193
 194         retval = mutex_lock_interruptible(&joydev->mutex);
 195         if (retval)
 196                 return retval;
 197
 198         if (!joydev->exist)
 199                 retval = -ENODEV;
 200         else if (!joydev->open++) {
 201                 retval = input_open_device(&joydev->handle);
 202                 if (retval)
 203                         joydev->open--;
 204         }
 205
 206         mutex_unlock(&joydev->mutex);
 207         return retval;
 208 }
 209
 210 static void joydev_close_device(struct joydev *joydev)
 211 {
 212         mutex_lock(&joydev->mutex);
 213
 214         if (joydev->exist && !--joydev->open)
 215                 input_close_device(&joydev->handle);
 216
 217         mutex_unlock(&joydev->mutex);
 218 }
 219
 220 /*
 221  * Wake up users waiting for IO so they can disconnect from
 222  * dead device.
 223  */
 224 static void joydev_hangup(struct joydev *joydev)
 225 {
 226         struct joydev_client *client;
 227
 228         spin_lock(&joydev->client_lock);
 229         list_for_each_entry(client, &joydev->client_list, node)
 230                 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
 231         spin_unlock(&joydev->client_lock);
 232
 233         wake_up_interruptible(&joydev->wait);
 234 }
 235
 236 static int joydev_release(struct inode *inode, struct file *file)
 237 {
 238         struct joydev_client *client = file->private_data;
 239         struct joydev *joydev = client->joydev;
 240
 241         joydev_detach_client(joydev, client);
 242         kfree(client);
 243
 244         joydev_close_device(joydev);
 245
 246         return 0;
 247 }
 248
 249 static int joydev_open(struct inode *inode, struct file *file)
 250 {
 251         struct joydev *joydev =
 252                         container_of(inode->i_cdev, struct joydev, cdev);
 253         struct joydev_client *client;
 254         int error;
 255
 256         client = kzalloc(sizeof(struct joydev_client), GFP_KERNEL);
 257         if (!client)
 258                 return -ENOMEM;
 259
 260         spin_lock_init(&client->buffer_lock);
 261         client->joydev = joydev;
 262         joydev_attach_client(joydev, client);
 263
 264         error = joydev_open_device(joydev);
 265         if (error)
 266                 goto err_free_client;
 267
 268         file->private_data = client;
 269         nonseekable_open(inode, file);
 270
 271         return 0;
 272
 273  err_free_client:
 274         joydev_detach_client(joydev, client);
 275         kfree(client);
 276         return error;
 277 }
 278
 279 static int joydev_generate_startup_event(struct joydev_client *client,
 280                                          struct input_dev *input,
 281                                          struct js_event *event)
 282 {
 283         struct joydev *joydev = client->joydev;
 284         int have_event;
 285
 286         spin_lock_irq(&client->buffer_lock);
 287
 288         have_event = client->startup < joydev->nabs + joydev->nkey;
 289
 290         if (have_event) {
 291
 292                 event->time = jiffies_to_msecs(jiffies);
 293                 if (client->startup < joydev->nkey) {
 294                         event->type = JS_EVENT_BUTTON | JS_EVENT_INIT;
 295                         event->number = client->startup;
 296                         event->value = !!test_bit(joydev->keypam[event->number],
 297                                                   input->key);
 298                 } else {
 299                         event->type = JS_EVENT_AXIS | JS_EVENT_INIT;
 300                         event->number = client->startup - joydev->nkey;
 301                         event->value = joydev->abs[event->number];
 302                 }
 303                 client->startup++;
 304         }
 305
 306         spin_unlock_irq(&client->buffer_lock);
 307
 308         return have_event;
 309 }
 310
 311 static int joydev_fetch_next_event(struct joydev_client *client,
 312                                    struct js_event *event)
 313 {
 314         int have_event;
 315
 316         spin_lock_irq(&client->buffer_lock);
 317
 318         have_event = client->head != client->tail;
 319         if (have_event) {
 320                 *event = client->buffer[client->tail++];
 321                 client->tail &= JOYDEV_BUFFER_SIZE - 1;
 322         }
 323
 324         spin_unlock_irq(&client->buffer_lock);
 325
 326         return have_event;
 327 }
 328
 329 /*
 330  * Old joystick interface
 331  */
 332 static ssize_t joydev_0x_read(struct joydev_client *client,
 333                               struct input_dev *input,
 334                               char __user *buf)
 335 {
 336         struct joydev *joydev = client->joydev;
 337         struct JS_DATA_TYPE data;
 338         int i;
 339
 340         spin_lock_irq(&input->event_lock);
 341
 342         /*
 343          * Get device state
 344          */
 345         for (data.buttons = i = 0; i < 32 && i < joydev->nkey; i++)
 346                 data.buttons |=
 347                         test_bit(joydev->keypam[i], input->key) ? (1 << i) : 0;
 348         data.x = (joydev->abs[0] / 256 + 128) >> joydev->glue.JS_CORR.x;
 349         data.y = (joydev->abs[1] / 256 + 128) >> joydev->glue.JS_CORR.y;
 350
 351         /*
 352          * Reset reader's event queue
 353          */
 354         spin_lock(&client->buffer_lock);
 355         client->startup = 0;
 356         client->tail = client->head;
 357         spin_unlock(&client->buffer_lock);
 358
 359         spin_unlock_irq(&input->event_lock);
 360
 361         if (copy_to_user(buf, &data, sizeof(struct JS_DATA_TYPE)))
 362                 return -EFAULT;
 363
 364         return sizeof(struct JS_DATA_TYPE);
 365 }
 366
 367 static inline int joydev_data_pending(struct joydev_client *client)
 368 {
 369         struct joydev *joydev = client->joydev;
 370
 371         return client->startup < joydev->nabs + joydev->nkey ||
 372                 client->head != client->tail;
 373 }
 374
 375 static ssize_t joydev_read(struct file *file, char __user *buf,
 376                            size_t count, loff_t *ppos)
 377 {
 378         struct joydev_client *client = file->private_data;
 379         struct joydev *joydev = client->joydev;
 380         struct input_dev *input = joydev->handle.dev;
 381         struct js_event event;
 382         int retval;
 383
 384         if (!joydev->exist)
 385                 return -ENODEV;
 386
 387         if (count < sizeof(struct js_event))
 388                 return -EINVAL;
 389
 390         if (count == sizeof(struct JS_DATA_TYPE))
 391                 return joydev_0x_read(client, input, buf);
 392
 393         if (!joydev_data_pending(client) && (file->f_flags & O_NONBLOCK))
 394                 return -EAGAIN;
 395
 396         retval = wait_event_interruptible(joydev->wait,
 397                         !joydev->exist || joydev_data_pending(client));
 398         if (retval)
 399                 return retval;
 400
 401         if (!joydev->exist)
 402                 return -ENODEV;
 403
 404         while (retval + sizeof(struct js_event) <= count &&
 405                joydev_generate_startup_event(client, input, &event)) {
 406
 407                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
 408                         return -EFAULT;
 409
 410                 retval += sizeof(struct js_event);
 411         }
 412
 413         while (retval + sizeof(struct js_event) <= count &&
 414                joydev_fetch_next_event(client, &event)) {
 415
 416                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
 417                         return -EFAULT;
 418
 419                 retval += sizeof(struct js_event);
 420         }
 421
 422         return retval;
 423 }
 424
 425 /* No kernel lock - fine */
 426 static unsigned int joydev_poll(struct file *file, poll_table *wait)
 427 {
 428         struct joydev_client *client = file->private_data;
 429         struct joydev *joydev = client->joydev;
 430
 431         poll_wait(file, &joydev->wait, wait);
 432         return (joydev_data_pending(client) ? (POLLIN | POLLRDNORM) : 0) |
 433                 (joydev->exist ?  0 : (POLLHUP | POLLERR));
 434 }
 435
 436 static int joydev_handle_JSIOCSAXMAP(struct joydev *joydev,
 437                                      void __user *argp, size_t len)
 438 {
 439         __u8 *abspam;
 440         int i;
 441         int retval = 0;
 442
 443         len = min(len, sizeof(joydev->abspam));
 444
 445         /* Validate the map. */
 446         abspam = memdup_user(argp, len);
 447         if (IS_ERR(abspam))
 448                 return PTR_ERR(abspam);
 449
 450         for (i = 0; i < joydev->nabs; i++) {
 451                 if (abspam[i] > ABS_MAX) {
 452                         retval = -EINVAL;
 453                         goto out;
 454                 }
 455         }
 456
 457         memcpy(joydev->abspam, abspam, len);
 458
 459         for (i = 0; i < joydev->nabs; i++)
 460                 joydev->absmap[joydev->abspam[i]] = i;
 461
 462  out:
 463         kfree(abspam);
 464         return retval;
 465 }
 466
 467 static int joydev_handle_JSIOCSBTNMAP(struct joydev *joydev,
 468                                       void __user *argp, size_t len)
 469 {
 470         __u16 *keypam;
 471         int i;
 472         int retval = 0;
 473
 474         len = min(len, sizeof(joydev->keypam));
 475
 476         /* Validate the map. */
 477         keypam = memdup_user(argp, len);
 478         if (IS_ERR(keypam))
 479                 return PTR_ERR(keypam);
 480
 481         for (i = 0; i < joydev->nkey; i++) {
 482                 if (keypam[i] > KEY_MAX || keypam[i] < BTN_MISC) {
 483                         retval = -EINVAL;
 484                         goto out;
 485                 }
 486         }
 487
 488         memcpy(joydev->keypam, keypam, len);
 489
 490         for (i = 0; i < joydev->nkey; i++)
 491                 joydev->keymap[keypam[i] - BTN_MISC] = i;
 492
 493  out:
 494         kfree(keypam);
 495         return retval;
 496 }
 497
 498
 499 static int joydev_ioctl_common(struct joydev *joydev,
 500                                 unsigned int cmd, void __user *argp)
 501 {
 502         struct input_dev *dev = joydev->handle.dev;
 503         size_t len;
 504         int i;
 505         const char *name;
 506
 507         /* Process fixed-sized commands. */
 508         switch (cmd) {
 509
 510         case JS_SET_CAL:
 511                 return copy_from_user(&joydev->glue.JS_CORR, argp,
 512                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
 513
 514         case JS_GET_CAL:
 515                 return copy_to_user(argp, &joydev->glue.JS_CORR,
 516                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
 517
 518         case JS_SET_TIMEOUT:
 519                 return get_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
 520
 521         case JS_GET_TIMEOUT:
 522                 return put_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
 523
 524         case JSIOCGVERSION:
 525                 return put_user(JS_VERSION, (__u32 __user *) argp);
 526
 527         case JSIOCGAXES:
 528                 return put_user(joydev->nabs, (__u8 __user *) argp);
 529
 530         case JSIOCGBUTTONS:
 531                 return put_user(joydev->nkey, (__u8 __user *) argp);
 532
 533         case JSIOCSCORR:
 534                 if (copy_from_user(joydev->corr, argp,
 535                               sizeof(joydev->corr[0]) * joydev->nabs))
 536                         return -EFAULT;
 537
 538                 for (i = 0; i < joydev->nabs; i++) {
 539                         int val = input_abs_get_val(dev, joydev->abspam[i]);
 540                         joydev->abs[i] = joydev_correct(val, &joydev->corr[i]);
 541                 }
 542                 return 0;
 543
 544         case JSIOCGCORR:
 545                 return copy_to_user(argp, joydev->corr,
 546                         sizeof(joydev->corr[0]) * joydev->nabs) ? -EFAULT : 0;
 547
 548         }
 549
 550         /*
 551          * Process variable-sized commands (the axis and button map commands
 552          * are considered variable-sized to decouple them from the values of
 553          * ABS_MAX and KEY_MAX).
 554          */
 555         switch (cmd & ~IOCSIZE_MASK) {
 556
 557         case (JSIOCSAXMAP & ~IOCSIZE_MASK):
 558                 return joydev_handle_JSIOCSAXMAP(joydev, argp, _IOC_SIZE(cmd));
 559
 560         case (JSIOCGAXMAP & ~IOCSIZE_MASK):
 561                 len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->abspam));
 562                 return copy_to_user(argp, joydev->abspam, len) ? -EFAULT : len;
 563
 564         case (JSIOCSBTNMAP & ~IOCSIZE_MASK):
 565                 return joydev_handle_JSIOCSBTNMAP(joydev, argp, _IOC_SIZE(cmd));
 566
 567         case (JSIOCGBTNMAP & ~IOCSIZE_MASK):
 568                 len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->keypam));
 569                 return copy_to_user(argp, joydev->keypam, len) ? -EFAULT : len;
 570
 571         case JSIOCGNAME(0):
 572                 name = dev->name;
 573                 if (!name)
 574                         return 0;
 575
 576                 len = min_t(size_t, _IOC_SIZE(cmd), strlen(name) + 1);
 577                 return copy_to_user(argp, name, len) ? -EFAULT : len;
 578         }
 579
 580         return -EINVAL;
 581 }
 582
 583 #ifdef CONFIG_COMPAT
 584 static long joydev_compat_ioctl(struct file *file,
 585                                 unsigned int cmd, unsigned long arg)
 586 {
 587         struct joydev_client *client = file->private_data;
 588         struct joydev *joydev = client->joydev;
 589         void __user *argp = (void __user *)arg;
 590         s32 tmp32;
 591         struct JS_DATA_SAVE_TYPE_32 ds32;
 592         int retval;
 593
 594         retval = mutex_lock_interruptible(&joydev->mutex);
 595         if (retval)
 596                 return retval;
 597
 598         if (!joydev->exist) {
 599                 retval = -ENODEV;
 600                 goto out;
 601         }
 602
 603         switch (cmd) {
 604
 605         case JS_SET_TIMELIMIT:
 606                 retval = get_user(tmp32, (s32 __user *) arg);
 607                 if (retval == 0)
 608                         joydev->glue.JS_TIMELIMIT = tmp32;
 609                 break;
 610
 611         case JS_GET_TIMELIMIT:
 612                 tmp32 = joydev->glue.JS_TIMELIMIT;
 613                 retval = put_user(tmp32, (s32 __user *) arg);
 614                 break;
 615
 616         case JS_SET_ALL:
 617                 retval = copy_from_user(&ds32, argp,
 618                                         sizeof(ds32)) ? -EFAULT : 0;
 619                 if (retval == 0) {
 620                         joydev->glue.JS_TIMEOUT    = ds32.JS_TIMEOUT;
 621                         joydev->glue.BUSY          = ds32.BUSY;
 622                         joydev->glue.JS_EXPIRETIME = ds32.JS_EXPIRETIME;
 623                         joydev->glue.JS_TIMELIMIT  = ds32.JS_TIMELIMIT;
 624                         joydev->glue.JS_SAVE       = ds32.JS_SAVE;
 625                         joydev->glue.JS_CORR       = ds32.JS_CORR;
 626                 }
 627                 break;
 628
 629         case JS_GET_ALL:
 630                 ds32.JS_TIMEOUT    = joydev->glue.JS_TIMEOUT;
 631                 ds32.BUSY          = joydev->glue.BUSY;
 632                 ds32.JS_EXPIRETIME = joydev->glue.JS_EXPIRETIME;
 633                 ds32.JS_TIMELIMIT  = joydev->glue.JS_TIMELIMIT;
 634                 ds32.JS_SAVE       = joydev->glue.JS_SAVE;
 635                 ds32.JS_CORR       = joydev->glue.JS_CORR;
 636
 637                 retval = copy_to_user(argp, &ds32, sizeof(ds32)) ? -EFAULT : 0;
 638                 break;
 639
 640         default:
 641                 retval = joydev_ioctl_common(joydev, cmd, argp);
 642                 break;
 643         }
 644
 645  out:
 646         mutex_unlock(&joydev->mutex);
 647         return retval;
 648 }
 649 #endif /* CONFIG_COMPAT */
 650
 651 static long joydev_ioctl(struct file *file,
 652                          unsigned int cmd, unsigned long arg)
 653 {
 654         struct joydev_client *client = file->private_data;
 655         struct joydev *joydev = client->joydev;
 656         void __user *argp = (void __user *)arg;
 657         int retval;
 658
 659         retval = mutex_lock_interruptible(&joydev->mutex);
 660         if (retval)
 661                 return retval;
 662
 663         if (!joydev->exist) {
 664                 retval = -ENODEV;
 665                 goto out;
 666         }
 667
 668         switch (cmd) {
 669
 670         case JS_SET_TIMELIMIT:
 671                 retval = get_user(joydev->glue.JS_TIMELIMIT,
 672                                   (long __user *) arg);
 673                 break;
 674
 675         case JS_GET_TIMELIMIT:
 676                 retval = put_user(joydev->glue.JS_TIMELIMIT,
 677                                   (long __user *) arg);
 678                 break;
 679
 680         case JS_SET_ALL:
 681                 retval = copy_from_user(&joydev->glue, argp,
 682                                         sizeof(joydev->glue)) ? -EFAULT : 0;
 683                 break;
 684
 685         case JS_GET_ALL:
 686                 retval = copy_to_user(argp, &joydev->glue,
 687                                       sizeof(joydev->glue)) ? -EFAULT : 0;
 688                 break;
 689
 690         default:
 691                 retval = joydev_ioctl_common(joydev, cmd, argp);
 692                 break;
 693         }
 694  out:
 695         mutex_unlock(&joydev->mutex);
 696         return retval;
 697 }
 698
 699 static const struct file_operations joydev_fops = {
 700         .owner          = THIS_MODULE,
 701         .read           = joydev_read,
 702         .poll           = joydev_poll,
 703         .open           = joydev_open,
 704         .release        = joydev_release,
 705         .unlocked_ioctl = joydev_ioctl,
 706 #ifdef CONFIG_COMPAT
 707         .compat_ioctl   = joydev_compat_ioctl,
 708 #endif
 709         .fasync         = joydev_fasync,
 710         .llseek         = no_llseek,
 711 };
 712
 713 /*
 714  * Mark device non-existent. This disables writes, ioctls and
 715  * prevents new users from opening the device. Already posted
 716  * blocking reads will stay, however new ones will fail.
 717  */
 718 static void joydev_mark_dead(struct joydev *joydev)
 719 {
 720         mutex_lock(&joydev->mutex);
 721         joydev->exist = false;
 722         mutex_unlock(&joydev->mutex);
 723 }
 724
 725 static void joydev_cleanup(struct joydev *joydev)
 726 {
 727         struct input_handle *handle = &joydev->handle;
 728
 729         joydev_mark_dead(joydev);
 730         joydev_hangup(joydev);
 731
 732         cdev_del(&joydev->cdev);
 733
 734         /* joydev is marked dead so no one else accesses joydev->open */
 735         if (joydev->open)
 736                 input_close_device(handle);
 737 }
 738
 739 static bool joydev_dev_is_absolute_mouse(struct input_dev *dev)
 740 {
 741         DECLARE_BITMAP(jd_scratch, KEY_CNT);
 742
 743         BUILD_BUG_ON(ABS_CNT > KEY_CNT || EV_CNT > KEY_CNT);
 744
 745         /*
 746          * Virtualization (VMware, etc) and remote management (HP
 747          * ILO2) solutions use absolute coordinates for their virtual
 748          * pointing devices so that there is one-to-one relationship
 749          * between pointer position on the host screen and virtual
 750          * guest screen, and so their mice use ABS_X, ABS_Y and 3
 751          * primary button events. This clashes with what joydev
 752          * considers to be joysticks (a device with at minimum ABS_X
 753          * axis).
 754          *
 755          * Here we are trying to separate absolute mice from
 756          * joysticks. A device is, for joystick detection purposes,
 757          * considered to be an absolute mouse if the following is
 758          * true:
 759          *
 760          * 1) Event types are exactly EV_ABS, EV_KEY and EV_SYN.
 761          * 2) Absolute events are exactly ABS_X and ABS_Y.
 762          * 3) Keys are exactly BTN_LEFT, BTN_RIGHT and BTN_MIDDLE.
 763          * 4) Device is not on "Amiga" bus.
 764          */
 765
 766         bitmap_zero(jd_scratch, EV_CNT);
 767         __set_bit(EV_ABS, jd_scratch);
 768         __set_bit(EV_KEY, jd_scratch);
 769         __set_bit(EV_SYN, jd_scratch);
 770         if (!bitmap_equal(jd_scratch, dev->evbit, EV_CNT))
 771                 return false;
 772
 773         bitmap_zero(jd_scratch, ABS_CNT);
 774         __set_bit(ABS_X, jd_scratch);
 775         __set_bit(ABS_Y, jd_scratch);
 776         if (!bitmap_equal(dev->absbit, jd_scratch, ABS_CNT))
 777                 return false;
 778
 779         bitmap_zero(jd_scratch, KEY_CNT);
 780         __set_bit(BTN_LEFT, jd_scratch);
 781         __set_bit(BTN_RIGHT, jd_scratch);
 782         __set_bit(BTN_MIDDLE, jd_scratch);
 783
 784         if (!bitmap_equal(dev->keybit, jd_scratch, KEY_CNT))
 785                 return false;
 786
 787         /*
 788          * Amiga joystick (amijoy) historically uses left/middle/right
 789          * button events.
 790          */
 791         if (dev->id.bustype == BUS_AMIGA)
 792                 return false;
 793
 794         return true;
 795 }
 796
 797 static bool joydev_match(struct input_handler *handler, struct input_dev *dev)
 798 {
 799         /* Avoid touchpads and touchscreens */
 800         if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_TOUCH, dev->keybit))
 801                 return false;
 802
 803         /* Avoid tablets, digitisers and similar devices */
 804         if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_DIGI, dev->keybit))
 805                 return false;
 806
 807         /* Avoid absolute mice */
 808         if (joydev_dev_is_absolute_mouse(dev))
 809                 return false;
 810
 811         return true;
 812 }
 813
 814 static int joydev_connect(struct input_handler *handler, struct input_dev *dev,
 815                           const struct input_device_id *id)
 816 {
 817         struct joydev *joydev;
 818         int i, j, t, minor, dev_no;
 819         int error;
 820
 821         minor = input_get_new_minor(JOYDEV_MINOR_BASE, JOYDEV_MINORS, true);
 822         if (minor < 0) {
 823                 error = minor;
 824                 pr_err("failed to reserve new minor: %d\n", error);
 825                 return error;
 826         }
 827
 828         joydev = kzalloc(sizeof(struct joydev), GFP_KERNEL);
 829         if (!joydev) {
 830                 error = -ENOMEM;
 831                 goto err_free_minor;
 832         }
 833
 834         INIT_LIST_HEAD(&joydev->client_list);
 835         spin_lock_init(&joydev->client_lock);
 836         mutex_init(&joydev->mutex);
 837         init_waitqueue_head(&joydev->wait);
 838         joydev->exist = true;
 839
 840         dev_no = minor;
 841         /* Normalize device number if it falls into legacy range */
 842         if (dev_no < JOYDEV_MINOR_BASE + JOYDEV_MINORS)
 843                 dev_no -= JOYDEV_MINOR_BASE;
 844         dev_set_name(&joydev->dev, "js%d", dev_no);
 845
 846         joydev->handle.dev = input_get_device(dev);
 847         joydev->handle.name = dev_name(&joydev->dev);
 848         joydev->handle.handler = handler;
 849         joydev->handle.private = joydev;
 850
 851         for_each_set_bit(i, dev->absbit, ABS_CNT) {
 852                 joydev->absmap[i] = joydev->nabs;
 853                 joydev->abspam[joydev->nabs] = i;
 854                 joydev->nabs++;
 855         }
 856
 857         for (i = BTN_JOYSTICK - BTN_MISC; i < KEY_MAX - BTN_MISC + 1; i++)
 858                 if (test_bit(i + BTN_MISC, dev->keybit)) {
 859                         joydev->keymap[i] = joydev->nkey;
 860                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
 861                         joydev->nkey++;
 862                 }
 863
 864         for (i = 0; i < BTN_JOYSTICK - BTN_MISC; i++)
 865                 if (test_bit(i + BTN_MISC, dev->keybit)) {
 866                         joydev->keymap[i] = joydev->nkey;
 867                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
 868                         joydev->nkey++;
 869                 }
 870
 871         for (i = 0; i < joydev->nabs; i++) {
 872                 j = joydev->abspam[i];
 873                 if (input_abs_get_max(dev, j) == input_abs_get_min(dev, j)) {
 874                         joydev->corr[i].type = JS_CORR_NONE;
 875                         joydev->abs[i] = input_abs_get_val(dev, j);
 876                         continue;
 877                 }
 878                 joydev->corr[i].type = JS_CORR_BROKEN;
 879                 joydev->corr[i].prec = input_abs_get_fuzz(dev, j);
 880
 881                 t = (input_abs_get_max(dev, j) + input_abs_get_min(dev, j)) / 2;
 882                 joydev->corr[i].coef[0] = t - input_abs_get_flat(dev, j);
 883                 joydev->corr[i].coef[1] = t + input_abs_get_flat(dev, j);
 884
 885                 t = (input_abs_get_max(dev, j) - input_abs_get_min(dev, j)) / 2
 886                         - 2 * input_abs_get_flat(dev, j);
 887                 if (t) {
 888                         joydev->corr[i].coef[2] = (1 << 29) / t;
 889                         joydev->corr[i].coef[3] = (1 << 29) / t;
 890
 891                         joydev->abs[i] =
 892                                 joydev_correct(input_abs_get_val(dev, j),
 893                                                joydev->corr + i);
 894                 }
 895         }
 896
 897         joydev->dev.devt = MKDEV(INPUT_MAJOR, minor);
 898         joydev->dev.class = &input_class;
 899         joydev->dev.parent = &dev->dev;
 900         joydev->dev.release = joydev_free;
 901         device_initialize(&joydev->dev);
 902
 903         error = input_register_handle(&joydev->handle);
 904         if (error)
 905                 goto err_free_joydev;
 906
 907         cdev_init(&joydev->cdev, &joydev_fops);
 908         joydev->cdev.kobj.parent = &joydev->dev.kobj;
 909         error = cdev_add(&joydev->cdev, joydev->dev.devt, 1);
 910         if (error)
 911                 goto err_unregister_handle;
 912
 913         error = device_add(&joydev->dev);
 914         if (error)
 915                 goto err_cleanup_joydev;
 916
 917         return 0;
 918
 919  err_cleanup_joydev:
 920         joydev_cleanup(joydev);
 921  err_unregister_handle:
 922         input_unregister_handle(&joydev->handle);
 923  err_free_joydev:
 924         put_device(&joydev->dev);
 925  err_free_minor:
 926         input_free_minor(minor);
 927         return error;
 928 }
 929
 930 static void joydev_disconnect(struct input_handle *handle)
 931 {
 932         struct joydev *joydev = handle->private;
 933
 934         device_del(&joydev->dev);
 935         joydev_cleanup(joydev);
 936         input_free_minor(MINOR(joydev->dev.devt));
 937         input_unregister_handle(handle);
 938         put_device(&joydev->dev);
 939 }
 940
 941 static const struct input_device_id joydev_ids[] = {
 942         {
 943                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 944                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 945                 .evbit = { BIT_MASK(EV_ABS) },
 946                 .absbit = { BIT_MASK(ABS_X) },
 947         },
 948         {
 949                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 950                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 951                 .evbit = { BIT_MASK(EV_ABS) },
 952                 .absbit = { BIT_MASK(ABS_Z) },
 953         },
 954         {
 955                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 956                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 957                 .evbit = { BIT_MASK(EV_ABS) },
 958                 .absbit = { BIT_MASK(ABS_WHEEL) },
 959         },
 960         {
 961                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 962                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 963                 .evbit = { BIT_MASK(EV_ABS) },
 964                 .absbit = { BIT_MASK(ABS_THROTTLE) },
 965         },
 966         {
 967                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 968                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
 969                 .evbit = { BIT_MASK(EV_KEY) },
 970                 .keybit = {[BIT_WORD(BTN_JOYSTICK)] = BIT_MASK(BTN_JOYSTICK) },
 971         },
 972         {
 973                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 974                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
 975                 .evbit = { BIT_MASK(EV_KEY) },
 976                 .keybit = { [BIT_WORD(BTN_GAMEPAD)] = BIT_MASK(BTN_GAMEPAD) },
 977         },
 978         {
 979                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 980                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
 981                 .evbit = { BIT_MASK(EV_KEY) },
 982                 .keybit = { [BIT_WORD(BTN_TRIGGER_HAPPY)] = BIT_MASK(BTN_TRIGGER_HAPPY) },
 983         },
 984         { }     /* Terminating entry */
 985 };
 986
 987 MODULE_DEVICE_TABLE(input, joydev_ids);
 988
 989 static struct input_handler joydev_handler = {
 990         .event          = joydev_event,
 991         .match          = joydev_match,
 992         .connect        = joydev_connect,
 993         .disconnect     = joydev_disconnect,
 994         .legacy_minors  = true,
 995         .minor          = JOYDEV_MINOR_BASE,
 996         .name           = "joydev",
 997         .id_table       = joydev_ids,
 998 };
 999
1000 static int __init joydev_init(void)
1001 {
1002         return input_register_handler(&joydev_handler);
1003 }
1004
1005 static void __exit joydev_exit(void)
1006 {
1007         input_unregister_handler(&joydev_handler);
1008 }
1009
1010 module_init(joydev_init);
1011 module_exit(joydev_exit);