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