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/sched.h>
  22 #include <linux/slab.h>
  23 #include <linux/mm.h>
  24 #include <linux/miscdevice.h>
  25 #include <linux/module.h>
  26 #include <linux/poll.h>
  27 #include <linux/init.h>
  28 #include <linux/device.h>
  29
  30 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
  31 MODULE_DESCRIPTION("Joystick device interfaces");
  32 MODULE_SUPPORTED_DEVICE("input/js");
  33 MODULE_LICENSE("GPL");
  34
  35 #define JOYDEV_MINOR_BASE       0
  36 #define JOYDEV_MINORS           16
  37 #define JOYDEV_BUFFER_SIZE      64
  38
  39 struct joydev {
  40         int exist;
  41         int open;
  42         int minor;
  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         nonseekable_open(inode, file);
 290
 291         return 0;
 292
 293  err_free_client:
 294         joydev_detach_client(joydev, client);
 295         kfree(client);
 296  err_put_joydev:
 297         put_device(&joydev->dev);
 298         return error;
 299 }
 300
 301 static int joydev_generate_startup_event(struct joydev_client *client,
 302                                          struct input_dev *input,
 303                                          struct js_event *event)
 304 {
 305         struct joydev *joydev = client->joydev;
 306         int have_event;
 307
 308         spin_lock_irq(&client->buffer_lock);
 309
 310         have_event = client->startup < joydev->nabs + joydev->nkey;
 311
 312         if (have_event) {
 313
 314                 event->time = jiffies_to_msecs(jiffies);
 315                 if (client->startup < joydev->nkey) {
 316                         event->type = JS_EVENT_BUTTON | JS_EVENT_INIT;
 317                         event->number = client->startup;
 318                         event->value = !!test_bit(joydev->keypam[event->number],
 319                                                   input->key);
 320                 } else {
 321                         event->type = JS_EVENT_AXIS | JS_EVENT_INIT;
 322                         event->number = client->startup - joydev->nkey;
 323                         event->value = joydev->abs[event->number];
 324                 }
 325                 client->startup++;
 326         }
 327
 328         spin_unlock_irq(&client->buffer_lock);
 329
 330         return have_event;
 331 }
 332
 333 static int joydev_fetch_next_event(struct joydev_client *client,
 334                                    struct js_event *event)
 335 {
 336         int have_event;
 337
 338         spin_lock_irq(&client->buffer_lock);
 339
 340         have_event = client->head != client->tail;
 341         if (have_event) {
 342                 *event = client->buffer[client->tail++];
 343                 client->tail &= JOYDEV_BUFFER_SIZE - 1;
 344         }
 345
 346         spin_unlock_irq(&client->buffer_lock);
 347
 348         return have_event;
 349 }
 350
 351 /*
 352  * Old joystick interface
 353  */
 354 static ssize_t joydev_0x_read(struct joydev_client *client,
 355                               struct input_dev *input,
 356                               char __user *buf)
 357 {
 358         struct joydev *joydev = client->joydev;
 359         struct JS_DATA_TYPE data;
 360         int i;
 361
 362         spin_lock_irq(&input->event_lock);
 363
 364         /*
 365          * Get device state
 366          */
 367         for (data.buttons = i = 0; i < 32 && i < joydev->nkey; i++)
 368                 data.buttons |=
 369                         test_bit(joydev->keypam[i], input->key) ? (1 << i) : 0;
 370         data.x = (joydev->abs[0] / 256 + 128) >> joydev->glue.JS_CORR.x;
 371         data.y = (joydev->abs[1] / 256 + 128) >> joydev->glue.JS_CORR.y;
 372
 373         /*
 374          * Reset reader's event queue
 375          */
 376         spin_lock(&client->buffer_lock);
 377         client->startup = 0;
 378         client->tail = client->head;
 379         spin_unlock(&client->buffer_lock);
 380
 381         spin_unlock_irq(&input->event_lock);
 382
 383         if (copy_to_user(buf, &data, sizeof(struct JS_DATA_TYPE)))
 384                 return -EFAULT;
 385
 386         return sizeof(struct JS_DATA_TYPE);
 387 }
 388
 389 static inline int joydev_data_pending(struct joydev_client *client)
 390 {
 391         struct joydev *joydev = client->joydev;
 392
 393         return client->startup < joydev->nabs + joydev->nkey ||
 394                 client->head != client->tail;
 395 }
 396
 397 static ssize_t joydev_read(struct file *file, char __user *buf,
 398                            size_t count, loff_t *ppos)
 399 {
 400         struct joydev_client *client = file->private_data;
 401         struct joydev *joydev = client->joydev;
 402         struct input_dev *input = joydev->handle.dev;
 403         struct js_event event;
 404         int retval;
 405
 406         if (!joydev->exist)
 407                 return -ENODEV;
 408
 409         if (count < sizeof(struct js_event))
 410                 return -EINVAL;
 411
 412         if (count == sizeof(struct JS_DATA_TYPE))
 413                 return joydev_0x_read(client, input, buf);
 414
 415         if (!joydev_data_pending(client) && (file->f_flags & O_NONBLOCK))
 416                 return -EAGAIN;
 417
 418         retval = wait_event_interruptible(joydev->wait,
 419                         !joydev->exist || joydev_data_pending(client));
 420         if (retval)
 421                 return retval;
 422
 423         if (!joydev->exist)
 424                 return -ENODEV;
 425
 426         while (retval + sizeof(struct js_event) <= count &&
 427                joydev_generate_startup_event(client, input, &event)) {
 428
 429                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
 430                         return -EFAULT;
 431
 432                 retval += sizeof(struct js_event);
 433         }
 434
 435         while (retval + sizeof(struct js_event) <= count &&
 436                joydev_fetch_next_event(client, &event)) {
 437
 438                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
 439                         return -EFAULT;
 440
 441                 retval += sizeof(struct js_event);
 442         }
 443
 444         return retval;
 445 }
 446
 447 /* No kernel lock - fine */
 448 static unsigned int joydev_poll(struct file *file, poll_table *wait)
 449 {
 450         struct joydev_client *client = file->private_data;
 451         struct joydev *joydev = client->joydev;
 452
 453         poll_wait(file, &joydev->wait, wait);
 454         return (joydev_data_pending(client) ? (POLLIN | POLLRDNORM) : 0) |
 455                 (joydev->exist ?  0 : (POLLHUP | POLLERR));
 456 }
 457
 458 static int joydev_handle_JSIOCSAXMAP(struct joydev *joydev,
 459                                      void __user *argp, size_t len)
 460 {
 461         __u8 *abspam;
 462         int i;
 463         int retval = 0;
 464
 465         len = min(len, sizeof(joydev->abspam));
 466
 467         /* Validate the map. */
 468         abspam = kmalloc(len, GFP_KERNEL);
 469         if (!abspam)
 470                 return -ENOMEM;
 471
 472         if (copy_from_user(abspam, argp, len)) {
 473                 retval = -EFAULT;
 474                 goto out;
 475         }
 476
 477         for (i = 0; i < joydev->nabs; i++) {
 478                 if (abspam[i] > ABS_MAX) {
 479                         retval = -EINVAL;
 480                         goto out;
 481                 }
 482         }
 483
 484         memcpy(joydev->abspam, abspam, len);
 485
 486  out:
 487         kfree(abspam);
 488         return retval;
 489 }
 490
 491 static int joydev_handle_JSIOCSBTNMAP(struct joydev *joydev,
 492                                       void __user *argp, size_t len)
 493 {
 494         __u16 *keypam;
 495         int i;
 496         int retval = 0;
 497
 498         len = min(len, sizeof(joydev->keypam));
 499
 500         /* Validate the map. */
 501         keypam = kmalloc(len, GFP_KERNEL);
 502         if (!keypam)
 503                 return -ENOMEM;
 504
 505         if (copy_from_user(keypam, argp, len)) {
 506                 retval = -EFAULT;
 507                 goto out;
 508         }
 509
 510         for (i = 0; i < joydev->nkey; i++) {
 511                 if (keypam[i] > KEY_MAX || keypam[i] < BTN_MISC) {
 512                         retval = -EINVAL;
 513                         goto out;
 514                 }
 515         }
 516
 517         memcpy(joydev->keypam, keypam, len);
 518
 519         for (i = 0; i < joydev->nkey; i++)
 520                 joydev->keymap[keypam[i] - BTN_MISC] = i;
 521
 522  out:
 523         kfree(keypam);
 524         return retval;
 525 }
 526
 527
 528 static int joydev_ioctl_common(struct joydev *joydev,
 529                                 unsigned int cmd, void __user *argp)
 530 {
 531         struct input_dev *dev = joydev->handle.dev;
 532         size_t len;
 533         int i, j;
 534         const char *name;
 535
 536         /* Process fixed-sized commands. */
 537         switch (cmd) {
 538
 539         case JS_SET_CAL:
 540                 return copy_from_user(&joydev->glue.JS_CORR, argp,
 541                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
 542
 543         case JS_GET_CAL:
 544                 return copy_to_user(argp, &joydev->glue.JS_CORR,
 545                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
 546
 547         case JS_SET_TIMEOUT:
 548                 return get_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
 549
 550         case JS_GET_TIMEOUT:
 551                 return put_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
 552
 553         case JSIOCGVERSION:
 554                 return put_user(JS_VERSION, (__u32 __user *) argp);
 555
 556         case JSIOCGAXES:
 557                 return put_user(joydev->nabs, (__u8 __user *) argp);
 558
 559         case JSIOCGBUTTONS:
 560                 return put_user(joydev->nkey, (__u8 __user *) argp);
 561
 562         case JSIOCSCORR:
 563                 if (copy_from_user(joydev->corr, argp,
 564                               sizeof(joydev->corr[0]) * joydev->nabs))
 565                     return -EFAULT;
 566
 567                 for (i = 0; i < joydev->nabs; i++) {
 568                         j = joydev->abspam[i];
 569                         joydev->abs[i] = joydev_correct(dev->abs[j],
 570                                                         &joydev->corr[i]);
 571                 }
 572                 return 0;
 573
 574         case JSIOCGCORR:
 575                 return copy_to_user(argp, joydev->corr,
 576                         sizeof(joydev->corr[0]) * joydev->nabs) ? -EFAULT : 0;
 577
 578         }
 579
 580         /*
 581          * Process variable-sized commands (the axis and button map commands
 582          * are considered variable-sized to decouple them from the values of
 583          * ABS_MAX and KEY_MAX).
 584          */
 585         switch (cmd & ~IOCSIZE_MASK) {
 586
 587         case (JSIOCSAXMAP & ~IOCSIZE_MASK):
 588                 return joydev_handle_JSIOCSAXMAP(joydev, argp, _IOC_SIZE(cmd));
 589
 590         case (JSIOCGAXMAP & ~IOCSIZE_MASK):
 591                 len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->abspam));
 592                 return copy_to_user(argp, joydev->abspam, len) ? -EFAULT : len;
 593
 594         case (JSIOCSBTNMAP & ~IOCSIZE_MASK):
 595                 return joydev_handle_JSIOCSBTNMAP(joydev, argp, _IOC_SIZE(cmd));
 596
 597         case (JSIOCGBTNMAP & ~IOCSIZE_MASK):
 598                 len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->keypam));
 599                 return copy_to_user(argp, joydev->keypam, len) ? -EFAULT : len;
 600
 601         case JSIOCGNAME(0):
 602                 name = dev->name;
 603                 if (!name)
 604                         return 0;
 605
 606                 len = min_t(size_t, _IOC_SIZE(cmd), strlen(name) + 1);
 607                 return copy_to_user(argp, name, len) ? -EFAULT : len;
 608         }
 609
 610         return -EINVAL;
 611 }
 612
 613 #ifdef CONFIG_COMPAT
 614 static long joydev_compat_ioctl(struct file *file,
 615                                 unsigned int cmd, unsigned long arg)
 616 {
 617         struct joydev_client *client = file->private_data;
 618         struct joydev *joydev = client->joydev;
 619         void __user *argp = (void __user *)arg;
 620         s32 tmp32;
 621         struct JS_DATA_SAVE_TYPE_32 ds32;
 622         int retval;
 623
 624         retval = mutex_lock_interruptible(&joydev->mutex);
 625         if (retval)
 626                 return retval;
 627
 628         if (!joydev->exist) {
 629                 retval = -ENODEV;
 630                 goto out;
 631         }
 632
 633         switch (cmd) {
 634
 635         case JS_SET_TIMELIMIT:
 636                 retval = get_user(tmp32, (s32 __user *) arg);
 637                 if (retval == 0)
 638                         joydev->glue.JS_TIMELIMIT = tmp32;
 639                 break;
 640
 641         case JS_GET_TIMELIMIT:
 642                 tmp32 = joydev->glue.JS_TIMELIMIT;
 643                 retval = put_user(tmp32, (s32 __user *) arg);
 644                 break;
 645
 646         case JS_SET_ALL:
 647                 retval = copy_from_user(&ds32, argp,
 648                                         sizeof(ds32)) ? -EFAULT : 0;
 649                 if (retval == 0) {
 650                         joydev->glue.JS_TIMEOUT    = ds32.JS_TIMEOUT;
 651                         joydev->glue.BUSY          = ds32.BUSY;
 652                         joydev->glue.JS_EXPIRETIME = ds32.JS_EXPIRETIME;
 653                         joydev->glue.JS_TIMELIMIT  = ds32.JS_TIMELIMIT;
 654                         joydev->glue.JS_SAVE       = ds32.JS_SAVE;
 655                         joydev->glue.JS_CORR       = ds32.JS_CORR;
 656                 }
 657                 break;
 658
 659         case JS_GET_ALL:
 660                 ds32.JS_TIMEOUT    = joydev->glue.JS_TIMEOUT;
 661                 ds32.BUSY          = joydev->glue.BUSY;
 662                 ds32.JS_EXPIRETIME = joydev->glue.JS_EXPIRETIME;
 663                 ds32.JS_TIMELIMIT  = joydev->glue.JS_TIMELIMIT;
 664                 ds32.JS_SAVE       = joydev->glue.JS_SAVE;
 665                 ds32.JS_CORR       = joydev->glue.JS_CORR;
 666
 667                 retval = copy_to_user(argp, &ds32, sizeof(ds32)) ? -EFAULT : 0;
 668                 break;
 669
 670         default:
 671                 retval = joydev_ioctl_common(joydev, cmd, argp);
 672                 break;
 673         }
 674
 675  out:
 676         mutex_unlock(&joydev->mutex);
 677         return retval;
 678 }
 679 #endif /* CONFIG_COMPAT */
 680
 681 static long joydev_ioctl(struct file *file,
 682                          unsigned int cmd, unsigned long arg)
 683 {
 684         struct joydev_client *client = file->private_data;
 685         struct joydev *joydev = client->joydev;
 686         void __user *argp = (void __user *)arg;
 687         int retval;
 688
 689         retval = mutex_lock_interruptible(&joydev->mutex);
 690         if (retval)
 691                 return retval;
 692
 693         if (!joydev->exist) {
 694                 retval = -ENODEV;
 695                 goto out;
 696         }
 697
 698         switch (cmd) {
 699
 700         case JS_SET_TIMELIMIT:
 701                 retval = get_user(joydev->glue.JS_TIMELIMIT,
 702                                   (long __user *) arg);
 703                 break;
 704
 705         case JS_GET_TIMELIMIT:
 706                 retval = put_user(joydev->glue.JS_TIMELIMIT,
 707                                   (long __user *) arg);
 708                 break;
 709
 710         case JS_SET_ALL:
 711                 retval = copy_from_user(&joydev->glue, argp,
 712                                         sizeof(joydev->glue)) ? -EFAULT: 0;
 713                 break;
 714
 715         case JS_GET_ALL:
 716                 retval = copy_to_user(argp, &joydev->glue,
 717                                       sizeof(joydev->glue)) ? -EFAULT : 0;
 718                 break;
 719
 720         default:
 721                 retval = joydev_ioctl_common(joydev, cmd, argp);
 722                 break;
 723         }
 724  out:
 725         mutex_unlock(&joydev->mutex);
 726         return retval;
 727 }
 728
 729 static const struct file_operations joydev_fops = {
 730         .owner          = THIS_MODULE,
 731         .read           = joydev_read,
 732         .poll           = joydev_poll,
 733         .open           = joydev_open,
 734         .release        = joydev_release,
 735         .unlocked_ioctl = joydev_ioctl,
 736 #ifdef CONFIG_COMPAT
 737         .compat_ioctl   = joydev_compat_ioctl,
 738 #endif
 739         .fasync         = joydev_fasync,
 740 };
 741
 742 static int joydev_install_chrdev(struct joydev *joydev)
 743 {
 744         joydev_table[joydev->minor] = joydev;
 745         return 0;
 746 }
 747
 748 static void joydev_remove_chrdev(struct joydev *joydev)
 749 {
 750         mutex_lock(&joydev_table_mutex);
 751         joydev_table[joydev->minor] = NULL;
 752         mutex_unlock(&joydev_table_mutex);
 753 }
 754
 755 /*
 756  * Mark device non-existant. This disables writes, ioctls and
 757  * prevents new users from opening the device. Already posted
 758  * blocking reads will stay, however new ones will fail.
 759  */
 760 static void joydev_mark_dead(struct joydev *joydev)
 761 {
 762         mutex_lock(&joydev->mutex);
 763         joydev->exist = 0;
 764         mutex_unlock(&joydev->mutex);
 765 }
 766
 767 static void joydev_cleanup(struct joydev *joydev)
 768 {
 769         struct input_handle *handle = &joydev->handle;
 770
 771         joydev_mark_dead(joydev);
 772         joydev_hangup(joydev);
 773         joydev_remove_chrdev(joydev);
 774
 775         /* joydev is marked dead so noone else accesses joydev->open */
 776         if (joydev->open)
 777                 input_close_device(handle);
 778 }
 779
 780
 781 static bool joydev_match(struct input_handler *handler, struct input_dev *dev)
 782 {
 783         /* Avoid touchpads and touchscreens */
 784         if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_TOUCH, dev->keybit))
 785                 return false;
 786
 787         /* Avoid tablets, digitisers and similar devices */
 788         if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_DIGI, dev->keybit))
 789                 return false;
 790
 791         return true;
 792 }
 793
 794 static int joydev_connect(struct input_handler *handler, struct input_dev *dev,
 795                           const struct input_device_id *id)
 796 {
 797         struct joydev *joydev;
 798         int i, j, t, minor;
 799         int error;
 800
 801         for (minor = 0; minor < JOYDEV_MINORS; minor++)
 802                 if (!joydev_table[minor])
 803                         break;
 804
 805         if (minor == JOYDEV_MINORS) {
 806                 printk(KERN_ERR "joydev: no more free joydev devices\n");
 807                 return -ENFILE;
 808         }
 809
 810         joydev = kzalloc(sizeof(struct joydev), GFP_KERNEL);
 811         if (!joydev)
 812                 return -ENOMEM;
 813
 814         INIT_LIST_HEAD(&joydev->client_list);
 815         spin_lock_init(&joydev->client_lock);
 816         mutex_init(&joydev->mutex);
 817         init_waitqueue_head(&joydev->wait);
 818
 819         dev_set_name(&joydev->dev, "js%d", minor);
 820         joydev->exist = 1;
 821         joydev->minor = minor;
 822
 823         joydev->exist = 1;
 824         joydev->handle.dev = input_get_device(dev);
 825         joydev->handle.name = dev_name(&joydev->dev);
 826         joydev->handle.handler = handler;
 827         joydev->handle.private = joydev;
 828
 829         for (i = 0; i < ABS_MAX + 1; i++)
 830                 if (test_bit(i, dev->absbit)) {
 831                         joydev->absmap[i] = joydev->nabs;
 832                         joydev->abspam[joydev->nabs] = i;
 833                         joydev->nabs++;
 834                 }
 835
 836         for (i = BTN_JOYSTICK - BTN_MISC; i < KEY_MAX - BTN_MISC + 1; i++)
 837                 if (test_bit(i + BTN_MISC, dev->keybit)) {
 838                         joydev->keymap[i] = joydev->nkey;
 839                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
 840                         joydev->nkey++;
 841                 }
 842
 843         for (i = 0; i < BTN_JOYSTICK - BTN_MISC; i++)
 844                 if (test_bit(i + BTN_MISC, dev->keybit)) {
 845                         joydev->keymap[i] = joydev->nkey;
 846                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
 847                         joydev->nkey++;
 848                 }
 849
 850         for (i = 0; i < joydev->nabs; i++) {
 851                 j = joydev->abspam[i];
 852                 if (dev->absmax[j] == dev->absmin[j]) {
 853                         joydev->corr[i].type = JS_CORR_NONE;
 854                         joydev->abs[i] = dev->abs[j];
 855                         continue;
 856                 }
 857                 joydev->corr[i].type = JS_CORR_BROKEN;
 858                 joydev->corr[i].prec = dev->absfuzz[j];
 859                 joydev->corr[i].coef[0] =
 860                         (dev->absmax[j] + dev->absmin[j]) / 2 - dev->absflat[j];
 861                 joydev->corr[i].coef[1] =
 862                         (dev->absmax[j] + dev->absmin[j]) / 2 + dev->absflat[j];
 863
 864                 t = (dev->absmax[j] - dev->absmin[j]) / 2 - 2 * dev->absflat[j];
 865                 if (t) {
 866                         joydev->corr[i].coef[2] = (1 << 29) / t;
 867                         joydev->corr[i].coef[3] = (1 << 29) / t;
 868
 869                         joydev->abs[i] = joydev_correct(dev->abs[j],
 870                                                         joydev->corr + i);
 871                 }
 872         }
 873
 874         joydev->dev.devt = MKDEV(INPUT_MAJOR, JOYDEV_MINOR_BASE + minor);
 875         joydev->dev.class = &input_class;
 876         joydev->dev.parent = &dev->dev;
 877         joydev->dev.release = joydev_free;
 878         device_initialize(&joydev->dev);
 879
 880         error = input_register_handle(&joydev->handle);
 881         if (error)
 882                 goto err_free_joydev;
 883
 884         error = joydev_install_chrdev(joydev);
 885         if (error)
 886                 goto err_unregister_handle;
 887
 888         error = device_add(&joydev->dev);
 889         if (error)
 890                 goto err_cleanup_joydev;
 891
 892         return 0;
 893
 894  err_cleanup_joydev:
 895         joydev_cleanup(joydev);
 896  err_unregister_handle:
 897         input_unregister_handle(&joydev->handle);
 898  err_free_joydev:
 899         put_device(&joydev->dev);
 900         return error;
 901 }
 902
 903 static void joydev_disconnect(struct input_handle *handle)
 904 {
 905         struct joydev *joydev = handle->private;
 906
 907         device_del(&joydev->dev);
 908         joydev_cleanup(joydev);
 909         input_unregister_handle(handle);
 910         put_device(&joydev->dev);
 911 }
 912
 913 static const struct input_device_id joydev_ids[] = {
 914         {
 915                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 916                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 917                 .evbit = { BIT_MASK(EV_ABS) },
 918                 .absbit = { BIT_MASK(ABS_X) },
 919         },
 920         {
 921                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 922                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 923                 .evbit = { BIT_MASK(EV_ABS) },
 924                 .absbit = { BIT_MASK(ABS_WHEEL) },
 925         },
 926         {
 927                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 928                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 929                 .evbit = { BIT_MASK(EV_ABS) },
 930                 .absbit = { BIT_MASK(ABS_THROTTLE) },
 931         },
 932         { }     /* Terminating entry */
 933 };
 934
 935 MODULE_DEVICE_TABLE(input, joydev_ids);
 936
 937 static struct input_handler joydev_handler = {
 938         .event          = joydev_event,
 939         .match          = joydev_match,
 940         .connect        = joydev_connect,
 941         .disconnect     = joydev_disconnect,
 942         .fops           = &joydev_fops,
 943         .minor          = JOYDEV_MINOR_BASE,
 944         .name           = "joydev",
 945         .id_table       = joydev_ids,
 946 };
 947
 948 static int __init joydev_init(void)
 949 {
 950         return input_register_handler(&joydev_handler);
 951 }
 952
 953 static void __exit joydev_exit(void)
 954 {
 955         input_unregister_handler(&joydev_handler);
 956 }
 957
 958 module_init(joydev_init);
 959 module_exit(joydev_exit);