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