git.oblomov.eu Git - linux-2.6/blob - 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 #include <asm/io.h>
  14 #include <asm/system.h>
  15 #include <linux/delay.h>
  16 #include <linux/errno.h>
  17 #include <linux/joystick.h>
  18 #include <linux/input.h>
  19 #include <linux/kernel.h>
  20 #include <linux/major.h>
  21 #include <linux/slab.h>
  22 #include <linux/mm.h>
  23 #include <linux/miscdevice.h>
  24 #include <linux/module.h>
  25 #include <linux/poll.h>
  26 #include <linux/init.h>
  27 #include <linux/device.h>
  28
  29 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
  30 MODULE_DESCRIPTION("Joystick device interfaces");
  31 MODULE_SUPPORTED_DEVICE("input/js");
  32 MODULE_LICENSE("GPL");
  33
  34 #define JOYDEV_MINOR_BASE       0
  35 #define JOYDEV_MINORS           16
  36 #define JOYDEV_BUFFER_SIZE      64
  37
  38 struct joydev {
  39         int exist;
  40         int open;
  41         int minor;
  42         char name[16];
  43         struct input_handle handle;
  44         wait_queue_head_t wait;
  45         struct list_head client_list;
  46         spinlock_t client_lock; /* protects client_list */
  47         struct mutex mutex;
  48         struct device dev;
  49
  50         struct js_corr corr[ABS_MAX + 1];
  51         struct JS_DATA_SAVE_TYPE glue;
  52         int nabs;
  53         int nkey;
  54         __u16 keymap[KEY_MAX - BTN_MISC + 1];
  55         __u16 keypam[KEY_MAX - BTN_MISC + 1];
  56         __u8 absmap[ABS_MAX + 1];
  57         __u8 abspam[ABS_MAX + 1];
  58         __s16 abs[ABS_MAX + 1];
  59 };
  60
  61 struct joydev_client {
  62         struct js_event buffer[JOYDEV_BUFFER_SIZE];
  63         int head;
  64         int tail;
  65         int startup;
  66         spinlock_t buffer_lock; /* protects access to buffer, head and tail */
  67         struct fasync_struct *fasync;
  68         struct joydev *joydev;
  69         struct list_head node;
  70 };
  71
  72 static struct joydev *joydev_table[JOYDEV_MINORS];
  73 static DEFINE_MUTEX(joydev_table_mutex);
  74
  75 static int joydev_correct(int value, struct js_corr *corr)
  76 {
  77         switch (corr->type) {
  78
  79         case JS_CORR_NONE:
  80                 break;
  81
  82         case JS_CORR_BROKEN:
  83                 value = value > corr->coef[0] ? (value < corr->coef[1] ? 0 :
  84                         ((corr->coef[3] * (value - corr->coef[1])) >> 14)) :
  85                         ((corr->coef[2] * (value - corr->coef[0])) >> 14);
  86                 break;
  87
  88         default:
  89                 return 0;
  90         }
  91
  92         return value < -32767 ? -32767 : (value > 32767 ? 32767 : value);
  93 }
  94
  95 static void joydev_pass_event(struct joydev_client *client,
  96                               struct js_event *event)
  97 {
  98         struct joydev *joydev = client->joydev;
  99
 100         /*
 101          * IRQs already disabled, just acquire the lock
 102          */
 103         spin_lock(&client->buffer_lock);
 104
 105         client->buffer[client->head] = *event;
 106
 107         if (client->startup == joydev->nabs + joydev->nkey) {
 108                 client->head++;
 109                 client->head &= JOYDEV_BUFFER_SIZE - 1;
 110                 if (client->tail == client->head)
 111                         client->startup = 0;
 112         }
 113
 114         spin_unlock(&client->buffer_lock);
 115
 116         kill_fasync(&client->fasync, SIGIO, POLL_IN);
 117 }
 118
 119 static void joydev_event(struct input_handle *handle,
 120                          unsigned int type, unsigned int code, int value)
 121 {
 122         struct joydev *joydev = handle->private;
 123         struct joydev_client *client;
 124         struct js_event event;
 125
 126         switch (type) {
 127
 128         case EV_KEY:
 129                 if (code < BTN_MISC || value == 2)
 130                         return;
 131                 event.type = JS_EVENT_BUTTON;
 132                 event.number = joydev->keymap[code - BTN_MISC];
 133                 event.value = value;
 134                 break;
 135
 136         case EV_ABS:
 137                 event.type = JS_EVENT_AXIS;
 138                 event.number = joydev->absmap[code];
 139                 event.value = joydev_correct(value,
 140                                         &joydev->corr[event.number]);
 141                 if (event.value == joydev->abs[event.number])
 142                         return;
 143                 joydev->abs[event.number] = event.value;
 144                 break;
 145
 146         default:
 147                 return;
 148         }
 149
 150         event.time = jiffies_to_msecs(jiffies);
 151
 152         rcu_read_lock();
 153         list_for_each_entry_rcu(client, &joydev->client_list, node)
 154                 joydev_pass_event(client, &event);
 155         rcu_read_unlock();
 156
 157         wake_up_interruptible(&joydev->wait);
 158 }
 159
 160 static int joydev_fasync(int fd, struct file *file, int on)
 161 {
 162         int retval;
 163         struct joydev_client *client = file->private_data;
 164
 165         retval = fasync_helper(fd, file, on, &client->fasync);
 166
 167         return retval < 0 ? retval : 0;
 168 }
 169
 170 static void joydev_free(struct device *dev)
 171 {
 172         struct joydev *joydev = container_of(dev, struct joydev, dev);
 173
 174         input_put_device(joydev->handle.dev);
 175         kfree(joydev);
 176 }
 177
 178 static void joydev_attach_client(struct joydev *joydev,
 179                                  struct joydev_client *client)
 180 {
 181         spin_lock(&joydev->client_lock);
 182         list_add_tail_rcu(&client->node, &joydev->client_list);
 183         spin_unlock(&joydev->client_lock);
 184         synchronize_rcu();
 185 }
 186
 187 static void joydev_detach_client(struct joydev *joydev,
 188                                  struct joydev_client *client)
 189 {
 190         spin_lock(&joydev->client_lock);
 191         list_del_rcu(&client->node);
 192         spin_unlock(&joydev->client_lock);
 193         synchronize_rcu();
 194 }
 195
 196 static int joydev_open_device(struct joydev *joydev)
 197 {
 198         int retval;
 199
 200         retval = mutex_lock_interruptible(&joydev->mutex);
 201         if (retval)
 202                 return retval;
 203
 204         if (!joydev->exist)
 205                 retval = -ENODEV;
 206         else if (!joydev->open++) {
 207                 retval = input_open_device(&joydev->handle);
 208                 if (retval)
 209                         joydev->open--;
 210         }
 211
 212         mutex_unlock(&joydev->mutex);
 213         return retval;
 214 }
 215
 216 static void joydev_close_device(struct joydev *joydev)
 217 {
 218         mutex_lock(&joydev->mutex);
 219
 220         if (joydev->exist && !--joydev->open)
 221                 input_close_device(&joydev->handle);
 222
 223         mutex_unlock(&joydev->mutex);
 224 }
 225
 226 /*
 227  * Wake up users waiting for IO so they can disconnect from
 228  * dead device.
 229  */
 230 static void joydev_hangup(struct joydev *joydev)
 231 {
 232         struct joydev_client *client;
 233
 234         spin_lock(&joydev->client_lock);
 235         list_for_each_entry(client, &joydev->client_list, node)
 236                 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
 237         spin_unlock(&joydev->client_lock);
 238
 239         wake_up_interruptible(&joydev->wait);
 240 }
 241
 242 static int joydev_release(struct inode *inode, struct file *file)
 243 {
 244         struct joydev_client *client = file->private_data;
 245         struct joydev *joydev = client->joydev;
 246
 247         joydev_fasync(-1, file, 0);
 248         joydev_detach_client(joydev, client);
 249         kfree(client);
 250
 251         joydev_close_device(joydev);
 252         put_device(&joydev->dev);
 253
 254         return 0;
 255 }
 256
 257 static int joydev_open(struct inode *inode, struct file *file)
 258 {
 259         struct joydev_client *client;
 260         struct joydev *joydev;
 261         int i = iminor(inode) - JOYDEV_MINOR_BASE;
 262         int error;
 263
 264         if (i >= JOYDEV_MINORS)
 265                 return -ENODEV;
 266
 267         error = mutex_lock_interruptible(&joydev_table_mutex);
 268         if (error)
 269                 return error;
 270         joydev = joydev_table[i];
 271         if (joydev)
 272                 get_device(&joydev->dev);
 273         mutex_unlock(&joydev_table_mutex);
 274
 275         if (!joydev)
 276                 return -ENODEV;
 277
 278         client = kzalloc(sizeof(struct joydev_client), GFP_KERNEL);
 279         if (!client) {
 280                 error = -ENOMEM;
 281                 goto err_put_joydev;
 282         }
 283
 284         spin_lock_init(&client->buffer_lock);
 285         client->joydev = joydev;
 286         joydev_attach_client(joydev, client);
 287
 288         error = joydev_open_device(joydev);
 289         if (error)
 290                 goto err_free_client;
 291
 292         file->private_data = client;
 293         return 0;
 294
 295  err_free_client:
 296         joydev_detach_client(joydev, client);
 297         kfree(client);
 298  err_put_joydev:
 299         put_device(&joydev->dev);
 300         return error;
 301 }
 302
 303 static int joydev_generate_startup_event(struct joydev_client *client,
 304                                          struct input_dev *input,
 305                                          struct js_event *event)
 306 {
 307         struct joydev *joydev = client->joydev;
 308         int have_event;
 309
 310         spin_lock_irq(&client->buffer_lock);
 311
 312         have_event = client->startup < joydev->nabs + joydev->nkey;
 313
 314         if (have_event) {
 315
 316                 event->time = jiffies_to_msecs(jiffies);
 317                 if (client->startup < joydev->nkey) {
 318                         event->type = JS_EVENT_BUTTON | JS_EVENT_INIT;
 319                         event->number = client->startup;
 320                         event->value = !!test_bit(joydev->keypam[event->number],
 321                                                   input->key);
 322                 } else {
 323                         event->type = JS_EVENT_AXIS | JS_EVENT_INIT;
 324                         event->number = client->startup - joydev->nkey;
 325                         event->value = joydev->abs[event->number];
 326                 }
 327                 client->startup++;
 328         }
 329
 330         spin_unlock_irq(&client->buffer_lock);
 331
 332         return have_event;
 333 }
 334
 335 static int joydev_fetch_next_event(struct joydev_client *client,
 336                                    struct js_event *event)
 337 {
 338         int have_event;
 339
 340         spin_lock_irq(&client->buffer_lock);
 341
 342         have_event = client->head != client->tail;
 343         if (have_event) {
 344                 *event = client->buffer[client->tail++];
 345                 client->tail &= JOYDEV_BUFFER_SIZE - 1;
 346         }
 347
 348         spin_unlock_irq(&client->buffer_lock);
 349
 350         return have_event;
 351 }
 352
 353 /*
 354  * Old joystick interface
 355  */
 356 static ssize_t joydev_0x_read(struct joydev_client *client,
 357                               struct input_dev *input,
 358                               char __user *buf)
 359 {
 360         struct joydev *joydev = client->joydev;
 361         struct JS_DATA_TYPE data;
 362         int i;
 363
 364         spin_lock_irq(&input->event_lock);
 365
 366         /*
 367          * Get device state
 368          */
 369         for (data.buttons = i = 0; i < 32 && i < joydev->nkey; i++)
 370                 data.buttons |=
 371                         test_bit(joydev->keypam[i], input->key) ? (1 << i) : 0;
 372         data.x = (joydev->abs[0] / 256 + 128) >> joydev->glue.JS_CORR.x;
 373         data.y = (joydev->abs[1] / 256 + 128) >> joydev->glue.JS_CORR.y;
 374
 375         /*
 376          * Reset reader's event queue
 377          */
 378         spin_lock(&client->buffer_lock);
 379         client->startup = 0;
 380         client->tail = client->head;
 381         spin_unlock(&client->buffer_lock);
 382
 383         spin_unlock_irq(&input->event_lock);
 384
 385         if (copy_to_user(buf, &data, sizeof(struct JS_DATA_TYPE)))
 386                 return -EFAULT;
 387
 388         return sizeof(struct JS_DATA_TYPE);
 389 }
 390
 391 static inline int joydev_data_pending(struct joydev_client *client)
 392 {
 393         struct joydev *joydev = client->joydev;
 394
 395         return client->startup < joydev->nabs + joydev->nkey ||
 396                 client->head != client->tail;
 397 }
 398
 399 static ssize_t joydev_read(struct file *file, char __user *buf,
 400                            size_t count, loff_t *ppos)
 401 {
 402         struct joydev_client *client = file->private_data;
 403         struct joydev *joydev = client->joydev;
 404         struct input_dev *input = joydev->handle.dev;
 405         struct js_event event;
 406         int retval;
 407
 408         if (!joydev->exist)
 409                 return -ENODEV;
 410
 411         if (count < sizeof(struct js_event))
 412                 return -EINVAL;
 413
 414         if (count == sizeof(struct JS_DATA_TYPE))
 415                 return joydev_0x_read(client, input, buf);
 416
 417         if (!joydev_data_pending(client) && (file->f_flags & O_NONBLOCK))
 418                 return -EAGAIN;
 419
 420         retval = wait_event_interruptible(joydev->wait,
 421                         !joydev->exist || joydev_data_pending(client));
 422         if (retval)
 423                 return retval;
 424
 425         if (!joydev->exist)
 426                 return -ENODEV;
 427
 428         while (retval + sizeof(struct js_event) <= count &&
 429                joydev_generate_startup_event(client, input, &event)) {
 430
 431                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
 432                         return -EFAULT;
 433
 434                 retval += sizeof(struct js_event);
 435         }
 436
 437         while (retval + sizeof(struct js_event) <= count &&
 438                joydev_fetch_next_event(client, &event)) {
 439
 440                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
 441                         return -EFAULT;
 442
 443                 retval += sizeof(struct js_event);
 444         }
 445
 446         return retval;
 447 }
 448
 449 /* No kernel lock - fine */
 450 static unsigned int joydev_poll(struct file *file, poll_table *wait)
 451 {
 452         struct joydev_client *client = file->private_data;
 453         struct joydev *joydev = client->joydev;
 454
 455         poll_wait(file, &joydev->wait, wait);
 456         return (joydev_data_pending(client) ? (POLLIN | POLLRDNORM) : 0) |
 457                 (joydev->exist ?  0 : (POLLHUP | POLLERR));
 458 }
 459
 460 static int joydev_ioctl_common(struct joydev *joydev,
 461                                 unsigned int cmd, void __user *argp)
 462 {
 463         struct input_dev *dev = joydev->handle.dev;
 464         int i, j;
 465
 466         switch (cmd) {
 467
 468         case JS_SET_CAL:
 469                 return copy_from_user(&joydev->glue.JS_CORR, argp,
 470                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
 471
 472         case JS_GET_CAL:
 473                 return copy_to_user(argp, &joydev->glue.JS_CORR,
 474                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
 475
 476         case JS_SET_TIMEOUT:
 477                 return get_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
 478
 479         case JS_GET_TIMEOUT:
 480                 return put_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
 481
 482         case JSIOCGVERSION:
 483                 return put_user(JS_VERSION, (__u32 __user *) argp);
 484
 485         case JSIOCGAXES:
 486                 return put_user(joydev->nabs, (__u8 __user *) argp);
 487
 488         case JSIOCGBUTTONS:
 489                 return put_user(joydev->nkey, (__u8 __user *) argp);
 490
 491         case JSIOCSCORR:
 492                 if (copy_from_user(joydev->corr, argp,
 493                               sizeof(joydev->corr[0]) * joydev->nabs))
 494                     return -EFAULT;
 495
 496                 for (i = 0; i < joydev->nabs; i++) {
 497                         j = joydev->abspam[i];
 498                         joydev->abs[i] = joydev_correct(dev->abs[j],
 499                                                         &joydev->corr[i]);
 500                 }
 501                 return 0;
 502
 503         case JSIOCGCORR:
 504                 return copy_to_user(argp, joydev->corr,
 505                         sizeof(joydev->corr[0]) * joydev->nabs) ? -EFAULT : 0;
 506
 507         case JSIOCSAXMAP:
 508                 if (copy_from_user(joydev->abspam, argp,
 509                                    sizeof(__u8) * (ABS_MAX + 1)))
 510                         return -EFAULT;
 511
 512                 for (i = 0; i < joydev->nabs; i++) {
 513                         if (joydev->abspam[i] > ABS_MAX)
 514                                 return -EINVAL;
 515                         joydev->absmap[joydev->abspam[i]] = i;
 516                 }
 517                 return 0;
 518
 519         case JSIOCGAXMAP:
 520                 return copy_to_user(argp, joydev->abspam,
 521                         sizeof(__u8) * (ABS_MAX + 1)) ? -EFAULT : 0;
 522
 523         case JSIOCSBTNMAP:
 524                 if (copy_from_user(joydev->keypam, argp,
 525                                    sizeof(__u16) * (KEY_MAX - BTN_MISC + 1)))
 526                         return -EFAULT;
 527
 528                 for (i = 0; i < joydev->nkey; i++) {
 529                         if (joydev->keypam[i] > KEY_MAX ||
 530                             joydev->keypam[i] < BTN_MISC)
 531                                 return -EINVAL;
 532                         joydev->keymap[joydev->keypam[i] - BTN_MISC] = i;
 533                 }
 534
 535                 return 0;
 536
 537         case JSIOCGBTNMAP:
 538                 return copy_to_user(argp, joydev->keypam,
 539                         sizeof(__u16) * (KEY_MAX - BTN_MISC + 1)) ? -EFAULT : 0;
 540
 541         default:
 542                 if ((cmd & ~IOCSIZE_MASK) == JSIOCGNAME(0)) {
 543                         int len;
 544                         if (!dev->name)
 545                                 return 0;
 546                         len = strlen(dev->name) + 1;
 547                         if (len > _IOC_SIZE(cmd))
 548                                 len = _IOC_SIZE(cmd);
 549                         if (copy_to_user(argp, dev->name, len))
 550                                 return -EFAULT;
 551                         return len;
 552                 }
 553         }
 554         return -EINVAL;
 555 }
 556
 557 #ifdef CONFIG_COMPAT
 558 static long joydev_compat_ioctl(struct file *file,
 559                                 unsigned int cmd, unsigned long arg)
 560 {
 561         struct joydev_client *client = file->private_data;
 562         struct joydev *joydev = client->joydev;
 563         void __user *argp = (void __user *)arg;
 564         s32 tmp32;
 565         struct JS_DATA_SAVE_TYPE_32 ds32;
 566         int retval;
 567
 568         retval = mutex_lock_interruptible(&joydev->mutex);
 569         if (retval)
 570                 return retval;
 571
 572         if (!joydev->exist) {
 573                 retval = -ENODEV;
 574                 goto out;
 575         }
 576
 577         switch (cmd) {
 578
 579         case JS_SET_TIMELIMIT:
 580                 retval = get_user(tmp32, (s32 __user *) arg);
 581                 if (retval == 0)
 582                         joydev->glue.JS_TIMELIMIT = tmp32;
 583                 break;
 584
 585         case JS_GET_TIMELIMIT:
 586                 tmp32 = joydev->glue.JS_TIMELIMIT;
 587                 retval = put_user(tmp32, (s32 __user *) arg);
 588                 break;
 589
 590         case JS_SET_ALL:
 591                 retval = copy_from_user(&ds32, argp,
 592                                         sizeof(ds32)) ? -EFAULT : 0;
 593                 if (retval == 0) {
 594                         joydev->glue.JS_TIMEOUT    = ds32.JS_TIMEOUT;
 595                         joydev->glue.BUSY          = ds32.BUSY;
 596                         joydev->glue.JS_EXPIRETIME = ds32.JS_EXPIRETIME;
 597                         joydev->glue.JS_TIMELIMIT  = ds32.JS_TIMELIMIT;
 598                         joydev->glue.JS_SAVE       = ds32.JS_SAVE;
 599                         joydev->glue.JS_CORR       = ds32.JS_CORR;
 600                 }
 601                 break;
 602
 603         case JS_GET_ALL:
 604                 ds32.JS_TIMEOUT    = joydev->glue.JS_TIMEOUT;
 605                 ds32.BUSY          = joydev->glue.BUSY;
 606                 ds32.JS_EXPIRETIME = joydev->glue.JS_EXPIRETIME;
 607                 ds32.JS_TIMELIMIT  = joydev->glue.JS_TIMELIMIT;
 608                 ds32.JS_SAVE       = joydev->glue.JS_SAVE;
 609                 ds32.JS_CORR       = joydev->glue.JS_CORR;
 610
 611                 retval = copy_to_user(argp, &ds32, sizeof(ds32)) ? -EFAULT : 0;
 612                 break;
 613
 614         default:
 615                 retval = joydev_ioctl_common(joydev, cmd, argp);
 616                 break;
 617         }
 618
 619  out:
 620         mutex_unlock(&joydev->mutex);
 621         return retval;
 622 }
 623 #endif /* CONFIG_COMPAT */
 624
 625 static long joydev_ioctl(struct file *file,
 626                          unsigned int cmd, unsigned long arg)
 627 {
 628         struct joydev_client *client = file->private_data;
 629         struct joydev *joydev = client->joydev;
 630         void __user *argp = (void __user *)arg;
 631         int retval;
 632
 633         retval = mutex_lock_interruptible(&joydev->mutex);
 634         if (retval)
 635                 return retval;
 636
 637         if (!joydev->exist) {
 638                 retval = -ENODEV;
 639                 goto out;
 640         }
 641
 642         switch (cmd) {
 643
 644         case JS_SET_TIMELIMIT:
 645                 retval = get_user(joydev->glue.JS_TIMELIMIT,
 646                                   (long __user *) arg);
 647                 break;
 648
 649         case JS_GET_TIMELIMIT:
 650                 retval = put_user(joydev->glue.JS_TIMELIMIT,
 651                                   (long __user *) arg);
 652                 break;
 653
 654         case JS_SET_ALL:
 655                 retval = copy_from_user(&joydev->glue, argp,
 656                                         sizeof(joydev->glue)) ? -EFAULT: 0;
 657                 break;
 658
 659         case JS_GET_ALL:
 660                 retval = copy_to_user(argp, &joydev->glue,
 661                                       sizeof(joydev->glue)) ? -EFAULT : 0;
 662                 break;
 663
 664         default:
 665                 retval = joydev_ioctl_common(joydev, cmd, argp);
 666                 break;
 667         }
 668  out:
 669         mutex_unlock(&joydev->mutex);
 670         return retval;
 671 }
 672
 673 static const struct file_operations joydev_fops = {
 674         .owner          = THIS_MODULE,
 675         .read           = joydev_read,
 676         .poll           = joydev_poll,
 677         .open           = joydev_open,
 678         .release        = joydev_release,
 679         .unlocked_ioctl = joydev_ioctl,
 680 #ifdef CONFIG_COMPAT
 681         .compat_ioctl   = joydev_compat_ioctl,
 682 #endif
 683         .fasync         = joydev_fasync,
 684 };
 685
 686 static int joydev_install_chrdev(struct joydev *joydev)
 687 {
 688         joydev_table[joydev->minor] = joydev;
 689         return 0;
 690 }
 691
 692 static void joydev_remove_chrdev(struct joydev *joydev)
 693 {
 694         mutex_lock(&joydev_table_mutex);
 695         joydev_table[joydev->minor] = NULL;
 696         mutex_unlock(&joydev_table_mutex);
 697 }
 698
 699 /*
 700  * Mark device non-existant. This disables writes, ioctls and
 701  * prevents new users from opening the device. Already posted
 702  * blocking reads will stay, however new ones will fail.
 703  */
 704 static void joydev_mark_dead(struct joydev *joydev)
 705 {
 706         mutex_lock(&joydev->mutex);
 707         joydev->exist = 0;
 708         mutex_unlock(&joydev->mutex);
 709 }
 710
 711 static void joydev_cleanup(struct joydev *joydev)
 712 {
 713         struct input_handle *handle = &joydev->handle;
 714
 715         joydev_mark_dead(joydev);
 716         joydev_hangup(joydev);
 717         joydev_remove_chrdev(joydev);
 718
 719         /* joydev is marked dead so noone else accesses joydev->open */
 720         if (joydev->open)
 721                 input_close_device(handle);
 722 }
 723
 724 static int joydev_connect(struct input_handler *handler, struct input_dev *dev,
 725                           const struct input_device_id *id)
 726 {
 727         struct joydev *joydev;
 728         int i, j, t, minor;
 729         int error;
 730
 731         for (minor = 0; minor < JOYDEV_MINORS; minor++)
 732                 if (!joydev_table[minor])
 733                         break;
 734
 735         if (minor == JOYDEV_MINORS) {
 736                 printk(KERN_ERR "joydev: no more free joydev devices\n");
 737                 return -ENFILE;
 738         }
 739
 740         joydev = kzalloc(sizeof(struct joydev), GFP_KERNEL);
 741         if (!joydev)
 742                 return -ENOMEM;
 743
 744         INIT_LIST_HEAD(&joydev->client_list);
 745         spin_lock_init(&joydev->client_lock);
 746         mutex_init(&joydev->mutex);
 747         init_waitqueue_head(&joydev->wait);
 748
 749         snprintf(joydev->name, sizeof(joydev->name), "js%d", minor);
 750         joydev->exist = 1;
 751         joydev->minor = minor;
 752
 753         joydev->exist = 1;
 754         joydev->handle.dev = input_get_device(dev);
 755         joydev->handle.name = joydev->name;
 756         joydev->handle.handler = handler;
 757         joydev->handle.private = joydev;
 758
 759         for (i = 0; i < ABS_MAX + 1; i++)
 760                 if (test_bit(i, dev->absbit)) {
 761                         joydev->absmap[i] = joydev->nabs;
 762                         joydev->abspam[joydev->nabs] = i;
 763                         joydev->nabs++;
 764                 }
 765
 766         for (i = BTN_JOYSTICK - BTN_MISC; i < KEY_MAX - BTN_MISC + 1; i++)
 767                 if (test_bit(i + BTN_MISC, dev->keybit)) {
 768                         joydev->keymap[i] = joydev->nkey;
 769                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
 770                         joydev->nkey++;
 771                 }
 772
 773         for (i = 0; i < BTN_JOYSTICK - BTN_MISC; i++)
 774                 if (test_bit(i + BTN_MISC, dev->keybit)) {
 775                         joydev->keymap[i] = joydev->nkey;
 776                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
 777                         joydev->nkey++;
 778                 }
 779
 780         for (i = 0; i < joydev->nabs; i++) {
 781                 j = joydev->abspam[i];
 782                 if (dev->absmax[j] == dev->absmin[j]) {
 783                         joydev->corr[i].type = JS_CORR_NONE;
 784                         joydev->abs[i] = dev->abs[j];
 785                         continue;
 786                 }
 787                 joydev->corr[i].type = JS_CORR_BROKEN;
 788                 joydev->corr[i].prec = dev->absfuzz[j];
 789                 joydev->corr[i].coef[0] =
 790                         (dev->absmax[j] + dev->absmin[j]) / 2 - dev->absflat[j];
 791                 joydev->corr[i].coef[1] =
 792                         (dev->absmax[j] + dev->absmin[j]) / 2 + dev->absflat[j];
 793
 794                 t = (dev->absmax[j] - dev->absmin[j]) / 2 - 2 * dev->absflat[j];
 795                 if (t) {
 796                         joydev->corr[i].coef[2] = (1 << 29) / t;
 797                         joydev->corr[i].coef[3] = (1 << 29) / t;
 798
 799                         joydev->abs[i] = joydev_correct(dev->abs[j],
 800                                                         joydev->corr + i);
 801                 }
 802         }
 803
 804         strlcpy(joydev->dev.bus_id, joydev->name, sizeof(joydev->dev.bus_id));
 805         joydev->dev.devt = MKDEV(INPUT_MAJOR, JOYDEV_MINOR_BASE + minor);
 806         joydev->dev.class = &input_class;
 807         joydev->dev.parent = &dev->dev;
 808         joydev->dev.release = joydev_free;
 809         device_initialize(&joydev->dev);
 810
 811         error = input_register_handle(&joydev->handle);
 812         if (error)
 813                 goto err_free_joydev;
 814
 815         error = joydev_install_chrdev(joydev);
 816         if (error)
 817                 goto err_unregister_handle;
 818
 819         error = device_add(&joydev->dev);
 820         if (error)
 821                 goto err_cleanup_joydev;
 822
 823         return 0;
 824
 825  err_cleanup_joydev:
 826         joydev_cleanup(joydev);
 827  err_unregister_handle:
 828         input_unregister_handle(&joydev->handle);
 829  err_free_joydev:
 830         put_device(&joydev->dev);
 831         return error;
 832 }
 833
 834 static void joydev_disconnect(struct input_handle *handle)
 835 {
 836         struct joydev *joydev = handle->private;
 837
 838         device_del(&joydev->dev);
 839         joydev_cleanup(joydev);
 840         input_unregister_handle(handle);
 841         put_device(&joydev->dev);
 842 }
 843
 844 static const struct input_device_id joydev_blacklist[] = {
 845         {
 846                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 847                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
 848                 .evbit = { BIT_MASK(EV_KEY) },
 849                 .keybit = { [BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) },
 850         },      /* Avoid itouchpads, touchscreens and tablets */
 851         { }     /* Terminating entry */
 852 };
 853
 854 static const struct input_device_id joydev_ids[] = {
 855         {
 856                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 857                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 858                 .evbit = { BIT_MASK(EV_ABS) },
 859                 .absbit = { BIT_MASK(ABS_X) },
 860         },
 861         {
 862                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 863                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 864                 .evbit = { BIT_MASK(EV_ABS) },
 865                 .absbit = { BIT_MASK(ABS_WHEEL) },
 866         },
 867         {
 868                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 869                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 870                 .evbit = { BIT_MASK(EV_ABS) },
 871                 .absbit = { BIT_MASK(ABS_THROTTLE) },
 872         },
 873         { }     /* Terminating entry */
 874 };
 875
 876 MODULE_DEVICE_TABLE(input, joydev_ids);
 877
 878 static struct input_handler joydev_handler = {
 879         .event          = joydev_event,
 880         .connect        = joydev_connect,
 881         .disconnect     = joydev_disconnect,
 882         .fops           = &joydev_fops,
 883         .minor          = JOYDEV_MINOR_BASE,
 884         .name           = "joydev",
 885         .id_table       = joydev_ids,
 886         .blacklist      = joydev_blacklist,
 887 };
 888
 889 static int __init joydev_init(void)
 890 {
 891         return input_register_handler(&joydev_handler);
 892 }
 893
 894 static void __exit joydev_exit(void)
 895 {
 896         input_unregister_handler(&joydev_handler);
 897 }
 898
 899 module_init(joydev_init);
 900 module_exit(joydev_exit);