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         struct joydev_client *client = file->private_data;
 163
 164         return fasync_helper(fd, file, on, &client->fasync);
 165 }
 166
 167 static void joydev_free(struct device *dev)
 168 {
 169         struct joydev *joydev = container_of(dev, struct joydev, dev);
 170
 171         input_put_device(joydev->handle.dev);
 172         kfree(joydev);
 173 }
 174
 175 static void joydev_attach_client(struct joydev *joydev,
 176                                  struct joydev_client *client)
 177 {
 178         spin_lock(&joydev->client_lock);
 179         list_add_tail_rcu(&client->node, &joydev->client_list);
 180         spin_unlock(&joydev->client_lock);
 181         synchronize_rcu();
 182 }
 183
 184 static void joydev_detach_client(struct joydev *joydev,
 185                                  struct joydev_client *client)
 186 {
 187         spin_lock(&joydev->client_lock);
 188         list_del_rcu(&client->node);
 189         spin_unlock(&joydev->client_lock);
 190         synchronize_rcu();
 191 }
 192
 193 static int joydev_open_device(struct joydev *joydev)
 194 {
 195         int retval;
 196
 197         retval = mutex_lock_interruptible(&joydev->mutex);
 198         if (retval)
 199                 return retval;
 200
 201         if (!joydev->exist)
 202                 retval = -ENODEV;
 203         else if (!joydev->open++) {
 204                 retval = input_open_device(&joydev->handle);
 205                 if (retval)
 206                         joydev->open--;
 207         }
 208
 209         mutex_unlock(&joydev->mutex);
 210         return retval;
 211 }
 212
 213 static void joydev_close_device(struct joydev *joydev)
 214 {
 215         mutex_lock(&joydev->mutex);
 216
 217         if (joydev->exist && !--joydev->open)
 218                 input_close_device(&joydev->handle);
 219
 220         mutex_unlock(&joydev->mutex);
 221 }
 222
 223 /*
 224  * Wake up users waiting for IO so they can disconnect from
 225  * dead device.
 226  */
 227 static void joydev_hangup(struct joydev *joydev)
 228 {
 229         struct joydev_client *client;
 230
 231         spin_lock(&joydev->client_lock);
 232         list_for_each_entry(client, &joydev->client_list, node)
 233                 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
 234         spin_unlock(&joydev->client_lock);
 235
 236         wake_up_interruptible(&joydev->wait);
 237 }
 238
 239 static int joydev_release(struct inode *inode, struct file *file)
 240 {
 241         struct joydev_client *client = file->private_data;
 242         struct joydev *joydev = client->joydev;
 243
 244         joydev_detach_client(joydev, client);
 245         kfree(client);
 246
 247         joydev_close_device(joydev);
 248         put_device(&joydev->dev);
 249
 250         return 0;
 251 }
 252
 253 static int joydev_open(struct inode *inode, struct file *file)
 254 {
 255         struct joydev_client *client;
 256         struct joydev *joydev;
 257         int i = iminor(inode) - JOYDEV_MINOR_BASE;
 258         int error;
 259
 260         if (i >= JOYDEV_MINORS)
 261                 return -ENODEV;
 262
 263         error = mutex_lock_interruptible(&joydev_table_mutex);
 264         if (error)
 265                 return error;
 266         joydev = joydev_table[i];
 267         if (joydev)
 268                 get_device(&joydev->dev);
 269         mutex_unlock(&joydev_table_mutex);
 270
 271         if (!joydev)
 272                 return -ENODEV;
 273
 274         client = kzalloc(sizeof(struct joydev_client), GFP_KERNEL);
 275         if (!client) {
 276                 error = -ENOMEM;
 277                 goto err_put_joydev;
 278         }
 279
 280         spin_lock_init(&client->buffer_lock);
 281         client->joydev = joydev;
 282         joydev_attach_client(joydev, client);
 283
 284         error = joydev_open_device(joydev);
 285         if (error)
 286                 goto err_free_client;
 287
 288         file->private_data = client;
 289         return 0;
 290
 291  err_free_client:
 292         joydev_detach_client(joydev, client);
 293         kfree(client);
 294  err_put_joydev:
 295         put_device(&joydev->dev);
 296         return error;
 297 }
 298
 299 static int joydev_generate_startup_event(struct joydev_client *client,
 300                                          struct input_dev *input,
 301                                          struct js_event *event)
 302 {
 303         struct joydev *joydev = client->joydev;
 304         int have_event;
 305
 306         spin_lock_irq(&client->buffer_lock);
 307
 308         have_event = client->startup < joydev->nabs + joydev->nkey;
 309
 310         if (have_event) {
 311
 312                 event->time = jiffies_to_msecs(jiffies);
 313                 if (client->startup < joydev->nkey) {
 314                         event->type = JS_EVENT_BUTTON | JS_EVENT_INIT;
 315                         event->number = client->startup;
 316                         event->value = !!test_bit(joydev->keypam[event->number],
 317                                                   input->key);
 318                 } else {
 319                         event->type = JS_EVENT_AXIS | JS_EVENT_INIT;
 320                         event->number = client->startup - joydev->nkey;
 321                         event->value = joydev->abs[event->number];
 322                 }
 323                 client->startup++;
 324         }
 325
 326         spin_unlock_irq(&client->buffer_lock);
 327
 328         return have_event;
 329 }
 330
 331 static int joydev_fetch_next_event(struct joydev_client *client,
 332                                    struct js_event *event)
 333 {
 334         int have_event;
 335
 336         spin_lock_irq(&client->buffer_lock);
 337
 338         have_event = client->head != client->tail;
 339         if (have_event) {
 340                 *event = client->buffer[client->tail++];
 341                 client->tail &= JOYDEV_BUFFER_SIZE - 1;
 342         }
 343
 344         spin_unlock_irq(&client->buffer_lock);
 345
 346         return have_event;
 347 }
 348
 349 /*
 350  * Old joystick interface
 351  */
 352 static ssize_t joydev_0x_read(struct joydev_client *client,
 353                               struct input_dev *input,
 354                               char __user *buf)
 355 {
 356         struct joydev *joydev = client->joydev;
 357         struct JS_DATA_TYPE data;
 358         int i;
 359
 360         spin_lock_irq(&input->event_lock);
 361
 362         /*
 363          * Get device state
 364          */
 365         for (data.buttons = i = 0; i < 32 && i < joydev->nkey; i++)
 366                 data.buttons |=
 367                         test_bit(joydev->keypam[i], input->key) ? (1 << i) : 0;
 368         data.x = (joydev->abs[0] / 256 + 128) >> joydev->glue.JS_CORR.x;
 369         data.y = (joydev->abs[1] / 256 + 128) >> joydev->glue.JS_CORR.y;
 370
 371         /*
 372          * Reset reader's event queue
 373          */
 374         spin_lock(&client->buffer_lock);
 375         client->startup = 0;
 376         client->tail = client->head;
 377         spin_unlock(&client->buffer_lock);
 378
 379         spin_unlock_irq(&input->event_lock);
 380
 381         if (copy_to_user(buf, &data, sizeof(struct JS_DATA_TYPE)))
 382                 return -EFAULT;
 383
 384         return sizeof(struct JS_DATA_TYPE);
 385 }
 386
 387 static inline int joydev_data_pending(struct joydev_client *client)
 388 {
 389         struct joydev *joydev = client->joydev;
 390
 391         return client->startup < joydev->nabs + joydev->nkey ||
 392                 client->head != client->tail;
 393 }
 394
 395 static ssize_t joydev_read(struct file *file, char __user *buf,
 396                            size_t count, loff_t *ppos)
 397 {
 398         struct joydev_client *client = file->private_data;
 399         struct joydev *joydev = client->joydev;
 400         struct input_dev *input = joydev->handle.dev;
 401         struct js_event event;
 402         int retval;
 403
 404         if (!joydev->exist)
 405                 return -ENODEV;
 406
 407         if (count < sizeof(struct js_event))
 408                 return -EINVAL;
 409
 410         if (count == sizeof(struct JS_DATA_TYPE))
 411                 return joydev_0x_read(client, input, buf);
 412
 413         if (!joydev_data_pending(client) && (file->f_flags & O_NONBLOCK))
 414                 return -EAGAIN;
 415
 416         retval = wait_event_interruptible(joydev->wait,
 417                         !joydev->exist || joydev_data_pending(client));
 418         if (retval)
 419                 return retval;
 420
 421         if (!joydev->exist)
 422                 return -ENODEV;
 423
 424         while (retval + sizeof(struct js_event) <= count &&
 425                joydev_generate_startup_event(client, input, &event)) {
 426
 427                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
 428                         return -EFAULT;
 429
 430                 retval += sizeof(struct js_event);
 431         }
 432
 433         while (retval + sizeof(struct js_event) <= count &&
 434                joydev_fetch_next_event(client, &event)) {
 435
 436                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
 437                         return -EFAULT;
 438
 439                 retval += sizeof(struct js_event);
 440         }
 441
 442         return retval;
 443 }
 444
 445 /* No kernel lock - fine */
 446 static unsigned int joydev_poll(struct file *file, poll_table *wait)
 447 {
 448         struct joydev_client *client = file->private_data;
 449         struct joydev *joydev = client->joydev;
 450
 451         poll_wait(file, &joydev->wait, wait);
 452         return (joydev_data_pending(client) ? (POLLIN | POLLRDNORM) : 0) |
 453                 (joydev->exist ?  0 : (POLLHUP | POLLERR));
 454 }
 455
 456 static int joydev_ioctl_common(struct joydev *joydev,
 457                                 unsigned int cmd, void __user *argp)
 458 {
 459         struct input_dev *dev = joydev->handle.dev;
 460         int i, j;
 461
 462         switch (cmd) {
 463
 464         case JS_SET_CAL:
 465                 return copy_from_user(&joydev->glue.JS_CORR, argp,
 466                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
 467
 468         case JS_GET_CAL:
 469                 return copy_to_user(argp, &joydev->glue.JS_CORR,
 470                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
 471
 472         case JS_SET_TIMEOUT:
 473                 return get_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
 474
 475         case JS_GET_TIMEOUT:
 476                 return put_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
 477
 478         case JSIOCGVERSION:
 479                 return put_user(JS_VERSION, (__u32 __user *) argp);
 480
 481         case JSIOCGAXES:
 482                 return put_user(joydev->nabs, (__u8 __user *) argp);
 483
 484         case JSIOCGBUTTONS:
 485                 return put_user(joydev->nkey, (__u8 __user *) argp);
 486
 487         case JSIOCSCORR:
 488                 if (copy_from_user(joydev->corr, argp,
 489                               sizeof(joydev->corr[0]) * joydev->nabs))
 490                     return -EFAULT;
 491
 492                 for (i = 0; i < joydev->nabs; i++) {
 493                         j = joydev->abspam[i];
 494                         joydev->abs[i] = joydev_correct(dev->abs[j],
 495                                                         &joydev->corr[i]);
 496                 }
 497                 return 0;
 498
 499         case JSIOCGCORR:
 500                 return copy_to_user(argp, joydev->corr,
 501                         sizeof(joydev->corr[0]) * joydev->nabs) ? -EFAULT : 0;
 502
 503         case JSIOCSAXMAP:
 504                 if (copy_from_user(joydev->abspam, argp,
 505                                    sizeof(__u8) * (ABS_MAX + 1)))
 506                         return -EFAULT;
 507
 508                 for (i = 0; i < joydev->nabs; i++) {
 509                         if (joydev->abspam[i] > ABS_MAX)
 510                                 return -EINVAL;
 511                         joydev->absmap[joydev->abspam[i]] = i;
 512                 }
 513                 return 0;
 514
 515         case JSIOCGAXMAP:
 516                 return copy_to_user(argp, joydev->abspam,
 517                         sizeof(__u8) * (ABS_MAX + 1)) ? -EFAULT : 0;
 518
 519         case JSIOCSBTNMAP:
 520                 if (copy_from_user(joydev->keypam, argp,
 521                                    sizeof(__u16) * (KEY_MAX - BTN_MISC + 1)))
 522                         return -EFAULT;
 523
 524                 for (i = 0; i < joydev->nkey; i++) {
 525                         if (joydev->keypam[i] > KEY_MAX ||
 526                             joydev->keypam[i] < BTN_MISC)
 527                                 return -EINVAL;
 528                         joydev->keymap[joydev->keypam[i] - BTN_MISC] = i;
 529                 }
 530
 531                 return 0;
 532
 533         case JSIOCGBTNMAP:
 534                 return copy_to_user(argp, joydev->keypam,
 535                         sizeof(__u16) * (KEY_MAX - BTN_MISC + 1)) ? -EFAULT : 0;
 536
 537         default:
 538                 if ((cmd & ~IOCSIZE_MASK) == JSIOCGNAME(0)) {
 539                         int len;
 540                         if (!dev->name)
 541                                 return 0;
 542                         len = strlen(dev->name) + 1;
 543                         if (len > _IOC_SIZE(cmd))
 544                                 len = _IOC_SIZE(cmd);
 545                         if (copy_to_user(argp, dev->name, len))
 546                                 return -EFAULT;
 547                         return len;
 548                 }
 549         }
 550         return -EINVAL;
 551 }
 552
 553 #ifdef CONFIG_COMPAT
 554 static long joydev_compat_ioctl(struct file *file,
 555                                 unsigned int cmd, unsigned long arg)
 556 {
 557         struct joydev_client *client = file->private_data;
 558         struct joydev *joydev = client->joydev;
 559         void __user *argp = (void __user *)arg;
 560         s32 tmp32;
 561         struct JS_DATA_SAVE_TYPE_32 ds32;
 562         int retval;
 563
 564         retval = mutex_lock_interruptible(&joydev->mutex);
 565         if (retval)
 566                 return retval;
 567
 568         if (!joydev->exist) {
 569                 retval = -ENODEV;
 570                 goto out;
 571         }
 572
 573         switch (cmd) {
 574
 575         case JS_SET_TIMELIMIT:
 576                 retval = get_user(tmp32, (s32 __user *) arg);
 577                 if (retval == 0)
 578                         joydev->glue.JS_TIMELIMIT = tmp32;
 579                 break;
 580
 581         case JS_GET_TIMELIMIT:
 582                 tmp32 = joydev->glue.JS_TIMELIMIT;
 583                 retval = put_user(tmp32, (s32 __user *) arg);
 584                 break;
 585
 586         case JS_SET_ALL:
 587                 retval = copy_from_user(&ds32, argp,
 588                                         sizeof(ds32)) ? -EFAULT : 0;
 589                 if (retval == 0) {
 590                         joydev->glue.JS_TIMEOUT    = ds32.JS_TIMEOUT;
 591                         joydev->glue.BUSY          = ds32.BUSY;
 592                         joydev->glue.JS_EXPIRETIME = ds32.JS_EXPIRETIME;
 593                         joydev->glue.JS_TIMELIMIT  = ds32.JS_TIMELIMIT;
 594                         joydev->glue.JS_SAVE       = ds32.JS_SAVE;
 595                         joydev->glue.JS_CORR       = ds32.JS_CORR;
 596                 }
 597                 break;
 598
 599         case JS_GET_ALL:
 600                 ds32.JS_TIMEOUT    = joydev->glue.JS_TIMEOUT;
 601                 ds32.BUSY          = joydev->glue.BUSY;
 602                 ds32.JS_EXPIRETIME = joydev->glue.JS_EXPIRETIME;
 603                 ds32.JS_TIMELIMIT  = joydev->glue.JS_TIMELIMIT;
 604                 ds32.JS_SAVE       = joydev->glue.JS_SAVE;
 605                 ds32.JS_CORR       = joydev->glue.JS_CORR;
 606
 607                 retval = copy_to_user(argp, &ds32, sizeof(ds32)) ? -EFAULT : 0;
 608                 break;
 609
 610         default:
 611                 retval = joydev_ioctl_common(joydev, cmd, argp);
 612                 break;
 613         }
 614
 615  out:
 616         mutex_unlock(&joydev->mutex);
 617         return retval;
 618 }
 619 #endif /* CONFIG_COMPAT */
 620
 621 static long joydev_ioctl(struct file *file,
 622                          unsigned int cmd, unsigned long arg)
 623 {
 624         struct joydev_client *client = file->private_data;
 625         struct joydev *joydev = client->joydev;
 626         void __user *argp = (void __user *)arg;
 627         int retval;
 628
 629         retval = mutex_lock_interruptible(&joydev->mutex);
 630         if (retval)
 631                 return retval;
 632
 633         if (!joydev->exist) {
 634                 retval = -ENODEV;
 635                 goto out;
 636         }
 637
 638         switch (cmd) {
 639
 640         case JS_SET_TIMELIMIT:
 641                 retval = get_user(joydev->glue.JS_TIMELIMIT,
 642                                   (long __user *) arg);
 643                 break;
 644
 645         case JS_GET_TIMELIMIT:
 646                 retval = put_user(joydev->glue.JS_TIMELIMIT,
 647                                   (long __user *) arg);
 648                 break;
 649
 650         case JS_SET_ALL:
 651                 retval = copy_from_user(&joydev->glue, argp,
 652                                         sizeof(joydev->glue)) ? -EFAULT: 0;
 653                 break;
 654
 655         case JS_GET_ALL:
 656                 retval = copy_to_user(argp, &joydev->glue,
 657                                       sizeof(joydev->glue)) ? -EFAULT : 0;
 658                 break;
 659
 660         default:
 661                 retval = joydev_ioctl_common(joydev, cmd, argp);
 662                 break;
 663         }
 664  out:
 665         mutex_unlock(&joydev->mutex);
 666         return retval;
 667 }
 668
 669 static const struct file_operations joydev_fops = {
 670         .owner          = THIS_MODULE,
 671         .read           = joydev_read,
 672         .poll           = joydev_poll,
 673         .open           = joydev_open,
 674         .release        = joydev_release,
 675         .unlocked_ioctl = joydev_ioctl,
 676 #ifdef CONFIG_COMPAT
 677         .compat_ioctl   = joydev_compat_ioctl,
 678 #endif
 679         .fasync         = joydev_fasync,
 680 };
 681
 682 static int joydev_install_chrdev(struct joydev *joydev)
 683 {
 684         joydev_table[joydev->minor] = joydev;
 685         return 0;
 686 }
 687
 688 static void joydev_remove_chrdev(struct joydev *joydev)
 689 {
 690         mutex_lock(&joydev_table_mutex);
 691         joydev_table[joydev->minor] = NULL;
 692         mutex_unlock(&joydev_table_mutex);
 693 }
 694
 695 /*
 696  * Mark device non-existant. This disables writes, ioctls and
 697  * prevents new users from opening the device. Already posted
 698  * blocking reads will stay, however new ones will fail.
 699  */
 700 static void joydev_mark_dead(struct joydev *joydev)
 701 {
 702         mutex_lock(&joydev->mutex);
 703         joydev->exist = 0;
 704         mutex_unlock(&joydev->mutex);
 705 }
 706
 707 static void joydev_cleanup(struct joydev *joydev)
 708 {
 709         struct input_handle *handle = &joydev->handle;
 710
 711         joydev_mark_dead(joydev);
 712         joydev_hangup(joydev);
 713         joydev_remove_chrdev(joydev);
 714
 715         /* joydev is marked dead so noone else accesses joydev->open */
 716         if (joydev->open)
 717                 input_close_device(handle);
 718 }
 719
 720 static int joydev_connect(struct input_handler *handler, struct input_dev *dev,
 721                           const struct input_device_id *id)
 722 {
 723         struct joydev *joydev;
 724         int i, j, t, minor;
 725         int error;
 726
 727         for (minor = 0; minor < JOYDEV_MINORS; minor++)
 728                 if (!joydev_table[minor])
 729                         break;
 730
 731         if (minor == JOYDEV_MINORS) {
 732                 printk(KERN_ERR "joydev: no more free joydev devices\n");
 733                 return -ENFILE;
 734         }
 735
 736         joydev = kzalloc(sizeof(struct joydev), GFP_KERNEL);
 737         if (!joydev)
 738                 return -ENOMEM;
 739
 740         INIT_LIST_HEAD(&joydev->client_list);
 741         spin_lock_init(&joydev->client_lock);
 742         mutex_init(&joydev->mutex);
 743         init_waitqueue_head(&joydev->wait);
 744
 745         snprintf(joydev->name, sizeof(joydev->name), "js%d", minor);
 746         joydev->exist = 1;
 747         joydev->minor = minor;
 748
 749         joydev->exist = 1;
 750         joydev->handle.dev = input_get_device(dev);
 751         joydev->handle.name = joydev->name;
 752         joydev->handle.handler = handler;
 753         joydev->handle.private = joydev;
 754
 755         for (i = 0; i < ABS_MAX + 1; i++)
 756                 if (test_bit(i, dev->absbit)) {
 757                         joydev->absmap[i] = joydev->nabs;
 758                         joydev->abspam[joydev->nabs] = i;
 759                         joydev->nabs++;
 760                 }
 761
 762         for (i = BTN_JOYSTICK - BTN_MISC; i < KEY_MAX - BTN_MISC + 1; i++)
 763                 if (test_bit(i + BTN_MISC, dev->keybit)) {
 764                         joydev->keymap[i] = joydev->nkey;
 765                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
 766                         joydev->nkey++;
 767                 }
 768
 769         for (i = 0; i < BTN_JOYSTICK - BTN_MISC; i++)
 770                 if (test_bit(i + BTN_MISC, dev->keybit)) {
 771                         joydev->keymap[i] = joydev->nkey;
 772                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
 773                         joydev->nkey++;
 774                 }
 775
 776         for (i = 0; i < joydev->nabs; i++) {
 777                 j = joydev->abspam[i];
 778                 if (dev->absmax[j] == dev->absmin[j]) {
 779                         joydev->corr[i].type = JS_CORR_NONE;
 780                         joydev->abs[i] = dev->abs[j];
 781                         continue;
 782                 }
 783                 joydev->corr[i].type = JS_CORR_BROKEN;
 784                 joydev->corr[i].prec = dev->absfuzz[j];
 785                 joydev->corr[i].coef[0] =
 786                         (dev->absmax[j] + dev->absmin[j]) / 2 - dev->absflat[j];
 787                 joydev->corr[i].coef[1] =
 788                         (dev->absmax[j] + dev->absmin[j]) / 2 + dev->absflat[j];
 789
 790                 t = (dev->absmax[j] - dev->absmin[j]) / 2 - 2 * dev->absflat[j];
 791                 if (t) {
 792                         joydev->corr[i].coef[2] = (1 << 29) / t;
 793                         joydev->corr[i].coef[3] = (1 << 29) / t;
 794
 795                         joydev->abs[i] = joydev_correct(dev->abs[j],
 796                                                         joydev->corr + i);
 797                 }
 798         }
 799
 800         dev_set_name(&joydev->dev, joydev->name);
 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);