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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  14
  15 #include <asm/io.h>
  16 #include <linux/delay.h>
  17 #include <linux/errno.h>
  18 #include <linux/joystick.h>
  19 #include <linux/input.h>
  20 #include <linux/kernel.h>
  21 #include <linux/major.h>
  22 #include <linux/sched.h>
  23 #include <linux/slab.h>
  24 #include <linux/mm.h>
  25 #include <linux/miscdevice.h>
  26 #include <linux/module.h>
  27 #include <linux/poll.h>
  28 #include <linux/init.h>
  29 #include <linux/device.h>
  30
  31 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
  32 MODULE_DESCRIPTION("Joystick device interfaces");
  33 MODULE_SUPPORTED_DEVICE("input/js");
  34 MODULE_LICENSE("GPL");
  35
  36 #define JOYDEV_MINOR_BASE       0
  37 #define JOYDEV_MINORS           16
  38 #define JOYDEV_BUFFER_SIZE      64
  39
  40 struct joydev {
  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         bool exist;
  50
  51         struct js_corr corr[ABS_CNT];
  52         struct JS_DATA_SAVE_TYPE glue;
  53         int nabs;
  54         int nkey;
  55         __u16 keymap[KEY_MAX - BTN_MISC + 1];
  56         __u16 keypam[KEY_MAX - BTN_MISC + 1];
  57         __u8 absmap[ABS_CNT];
  58         __u8 abspam[ABS_CNT];
  59         __s16 abs[ABS_CNT];
  60 };
  61
  62 struct joydev_client {
  63         struct js_event buffer[JOYDEV_BUFFER_SIZE];
  64         int head;
  65         int tail;
  66         int startup;
  67         spinlock_t buffer_lock; /* protects access to buffer, head and tail */
  68         struct fasync_struct *fasync;
  69         struct joydev *joydev;
  70         struct list_head node;
  71 };
  72
  73 static struct joydev *joydev_table[JOYDEV_MINORS];
  74 static DEFINE_MUTEX(joydev_table_mutex);
  75
  76 static int joydev_correct(int value, struct js_corr *corr)
  77 {
  78         switch (corr->type) {
  79
  80         case JS_CORR_NONE:
  81                 break;
  82
  83         case JS_CORR_BROKEN:
  84                 value = value > corr->coef[0] ? (value < corr->coef[1] ? 0 :
  85                         ((corr->coef[3] * (value - corr->coef[1])) >> 14)) :
  86                         ((corr->coef[2] * (value - corr->coef[0])) >> 14);
  87                 break;
  88
  89         default:
  90                 return 0;
  91         }
  92
  93         return value < -32767 ? -32767 : (value > 32767 ? 32767 : value);
  94 }
  95
  96 static void joydev_pass_event(struct joydev_client *client,
  97                               struct js_event *event)
  98 {
  99         struct joydev *joydev = client->joydev;
 100
 101         /*
 102          * IRQs already disabled, just acquire the lock
 103          */
 104         spin_lock(&client->buffer_lock);
 105
 106         client->buffer[client->head] = *event;
 107
 108         if (client->startup == joydev->nabs + joydev->nkey) {
 109                 client->head++;
 110                 client->head &= JOYDEV_BUFFER_SIZE - 1;
 111                 if (client->tail == client->head)
 112                         client->startup = 0;
 113         }
 114
 115         spin_unlock(&client->buffer_lock);
 116
 117         kill_fasync(&client->fasync, SIGIO, POLL_IN);
 118 }
 119
 120 static void joydev_event(struct input_handle *handle,
 121                          unsigned int type, unsigned int code, int value)
 122 {
 123         struct joydev *joydev = handle->private;
 124         struct joydev_client *client;
 125         struct js_event event;
 126
 127         switch (type) {
 128
 129         case EV_KEY:
 130                 if (code < BTN_MISC || value == 2)
 131                         return;
 132                 event.type = JS_EVENT_BUTTON;
 133                 event.number = joydev->keymap[code - BTN_MISC];
 134                 event.value = value;
 135                 break;
 136
 137         case EV_ABS:
 138                 event.type = JS_EVENT_AXIS;
 139                 event.number = joydev->absmap[code];
 140                 event.value = joydev_correct(value,
 141                                         &joydev->corr[event.number]);
 142                 if (event.value == joydev->abs[event.number])
 143                         return;
 144                 joydev->abs[event.number] = event.value;
 145                 break;
 146
 147         default:
 148                 return;
 149         }
 150
 151         event.time = jiffies_to_msecs(jiffies);
 152
 153         rcu_read_lock();
 154         list_for_each_entry_rcu(client, &joydev->client_list, node)
 155                 joydev_pass_event(client, &event);
 156         rcu_read_unlock();
 157
 158         wake_up_interruptible(&joydev->wait);
 159 }
 160
 161 static int joydev_fasync(int fd, struct file *file, int on)
 162 {
 163         struct joydev_client *client = file->private_data;
 164
 165         return fasync_helper(fd, file, on, &client->fasync);
 166 }
 167
 168 static void joydev_free(struct device *dev)
 169 {
 170         struct joydev *joydev = container_of(dev, struct joydev, dev);
 171
 172         input_put_device(joydev->handle.dev);
 173         kfree(joydev);
 174 }
 175
 176 static void joydev_attach_client(struct joydev *joydev,
 177                                  struct joydev_client *client)
 178 {
 179         spin_lock(&joydev->client_lock);
 180         list_add_tail_rcu(&client->node, &joydev->client_list);
 181         spin_unlock(&joydev->client_lock);
 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         for (i = 0; i < joydev->nabs; i++)
 487                 joydev->absmap[joydev->abspam[i]] = i;
 488
 489  out:
 490         kfree(abspam);
 491         return retval;
 492 }
 493
 494 static int joydev_handle_JSIOCSBTNMAP(struct joydev *joydev,
 495                                       void __user *argp, size_t len)
 496 {
 497         __u16 *keypam;
 498         int i;
 499         int retval = 0;
 500
 501         len = min(len, sizeof(joydev->keypam));
 502
 503         /* Validate the map. */
 504         keypam = kmalloc(len, GFP_KERNEL);
 505         if (!keypam)
 506                 return -ENOMEM;
 507
 508         if (copy_from_user(keypam, argp, len)) {
 509                 retval = -EFAULT;
 510                 goto out;
 511         }
 512
 513         for (i = 0; i < joydev->nkey; i++) {
 514                 if (keypam[i] > KEY_MAX || keypam[i] < BTN_MISC) {
 515                         retval = -EINVAL;
 516                         goto out;
 517                 }
 518         }
 519
 520         memcpy(joydev->keypam, keypam, len);
 521
 522         for (i = 0; i < joydev->nkey; i++)
 523                 joydev->keymap[keypam[i] - BTN_MISC] = i;
 524
 525  out:
 526         kfree(keypam);
 527         return retval;
 528 }
 529
 530
 531 static int joydev_ioctl_common(struct joydev *joydev,
 532                                 unsigned int cmd, void __user *argp)
 533 {
 534         struct input_dev *dev = joydev->handle.dev;
 535         size_t len;
 536         int i;
 537         const char *name;
 538
 539         /* Process fixed-sized commands. */
 540         switch (cmd) {
 541
 542         case JS_SET_CAL:
 543                 return copy_from_user(&joydev->glue.JS_CORR, argp,
 544                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
 545
 546         case JS_GET_CAL:
 547                 return copy_to_user(argp, &joydev->glue.JS_CORR,
 548                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
 549
 550         case JS_SET_TIMEOUT:
 551                 return get_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
 552
 553         case JS_GET_TIMEOUT:
 554                 return put_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
 555
 556         case JSIOCGVERSION:
 557                 return put_user(JS_VERSION, (__u32 __user *) argp);
 558
 559         case JSIOCGAXES:
 560                 return put_user(joydev->nabs, (__u8 __user *) argp);
 561
 562         case JSIOCGBUTTONS:
 563                 return put_user(joydev->nkey, (__u8 __user *) argp);
 564
 565         case JSIOCSCORR:
 566                 if (copy_from_user(joydev->corr, argp,
 567                               sizeof(joydev->corr[0]) * joydev->nabs))
 568                         return -EFAULT;
 569
 570                 for (i = 0; i < joydev->nabs; i++) {
 571                         int val = input_abs_get_val(dev, joydev->abspam[i]);
 572                         joydev->abs[i] = joydev_correct(val, &joydev->corr[i]);
 573                 }
 574                 return 0;
 575
 576         case JSIOCGCORR:
 577                 return copy_to_user(argp, joydev->corr,
 578                         sizeof(joydev->corr[0]) * joydev->nabs) ? -EFAULT : 0;
 579
 580         }
 581
 582         /*
 583          * Process variable-sized commands (the axis and button map commands
 584          * are considered variable-sized to decouple them from the values of
 585          * ABS_MAX and KEY_MAX).
 586          */
 587         switch (cmd & ~IOCSIZE_MASK) {
 588
 589         case (JSIOCSAXMAP & ~IOCSIZE_MASK):
 590                 return joydev_handle_JSIOCSAXMAP(joydev, argp, _IOC_SIZE(cmd));
 591
 592         case (JSIOCGAXMAP & ~IOCSIZE_MASK):
 593                 len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->abspam));
 594                 return copy_to_user(argp, joydev->abspam, len) ? -EFAULT : len;
 595
 596         case (JSIOCSBTNMAP & ~IOCSIZE_MASK):
 597                 return joydev_handle_JSIOCSBTNMAP(joydev, argp, _IOC_SIZE(cmd));
 598
 599         case (JSIOCGBTNMAP & ~IOCSIZE_MASK):
 600                 len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->keypam));
 601                 return copy_to_user(argp, joydev->keypam, len) ? -EFAULT : len;
 602
 603         case JSIOCGNAME(0):
 604                 name = dev->name;
 605                 if (!name)
 606                         return 0;
 607
 608                 len = min_t(size_t, _IOC_SIZE(cmd), strlen(name) + 1);
 609                 return copy_to_user(argp, name, len) ? -EFAULT : len;
 610         }
 611
 612         return -EINVAL;
 613 }
 614
 615 #ifdef CONFIG_COMPAT
 616 static long joydev_compat_ioctl(struct file *file,
 617                                 unsigned int cmd, unsigned long arg)
 618 {
 619         struct joydev_client *client = file->private_data;
 620         struct joydev *joydev = client->joydev;
 621         void __user *argp = (void __user *)arg;
 622         s32 tmp32;
 623         struct JS_DATA_SAVE_TYPE_32 ds32;
 624         int retval;
 625
 626         retval = mutex_lock_interruptible(&joydev->mutex);
 627         if (retval)
 628                 return retval;
 629
 630         if (!joydev->exist) {
 631                 retval = -ENODEV;
 632                 goto out;
 633         }
 634
 635         switch (cmd) {
 636
 637         case JS_SET_TIMELIMIT:
 638                 retval = get_user(tmp32, (s32 __user *) arg);
 639                 if (retval == 0)
 640                         joydev->glue.JS_TIMELIMIT = tmp32;
 641                 break;
 642
 643         case JS_GET_TIMELIMIT:
 644                 tmp32 = joydev->glue.JS_TIMELIMIT;
 645                 retval = put_user(tmp32, (s32 __user *) arg);
 646                 break;
 647
 648         case JS_SET_ALL:
 649                 retval = copy_from_user(&ds32, argp,
 650                                         sizeof(ds32)) ? -EFAULT : 0;
 651                 if (retval == 0) {
 652                         joydev->glue.JS_TIMEOUT    = ds32.JS_TIMEOUT;
 653                         joydev->glue.BUSY          = ds32.BUSY;
 654                         joydev->glue.JS_EXPIRETIME = ds32.JS_EXPIRETIME;
 655                         joydev->glue.JS_TIMELIMIT  = ds32.JS_TIMELIMIT;
 656                         joydev->glue.JS_SAVE       = ds32.JS_SAVE;
 657                         joydev->glue.JS_CORR       = ds32.JS_CORR;
 658                 }
 659                 break;
 660
 661         case JS_GET_ALL:
 662                 ds32.JS_TIMEOUT    = joydev->glue.JS_TIMEOUT;
 663                 ds32.BUSY          = joydev->glue.BUSY;
 664                 ds32.JS_EXPIRETIME = joydev->glue.JS_EXPIRETIME;
 665                 ds32.JS_TIMELIMIT  = joydev->glue.JS_TIMELIMIT;
 666                 ds32.JS_SAVE       = joydev->glue.JS_SAVE;
 667                 ds32.JS_CORR       = joydev->glue.JS_CORR;
 668
 669                 retval = copy_to_user(argp, &ds32, sizeof(ds32)) ? -EFAULT : 0;
 670                 break;
 671
 672         default:
 673                 retval = joydev_ioctl_common(joydev, cmd, argp);
 674                 break;
 675         }
 676
 677  out:
 678         mutex_unlock(&joydev->mutex);
 679         return retval;
 680 }
 681 #endif /* CONFIG_COMPAT */
 682
 683 static long joydev_ioctl(struct file *file,
 684                          unsigned int cmd, unsigned long arg)
 685 {
 686         struct joydev_client *client = file->private_data;
 687         struct joydev *joydev = client->joydev;
 688         void __user *argp = (void __user *)arg;
 689         int retval;
 690
 691         retval = mutex_lock_interruptible(&joydev->mutex);
 692         if (retval)
 693                 return retval;
 694
 695         if (!joydev->exist) {
 696                 retval = -ENODEV;
 697                 goto out;
 698         }
 699
 700         switch (cmd) {
 701
 702         case JS_SET_TIMELIMIT:
 703                 retval = get_user(joydev->glue.JS_TIMELIMIT,
 704                                   (long __user *) arg);
 705                 break;
 706
 707         case JS_GET_TIMELIMIT:
 708                 retval = put_user(joydev->glue.JS_TIMELIMIT,
 709                                   (long __user *) arg);
 710                 break;
 711
 712         case JS_SET_ALL:
 713                 retval = copy_from_user(&joydev->glue, argp,
 714                                         sizeof(joydev->glue)) ? -EFAULT: 0;
 715                 break;
 716
 717         case JS_GET_ALL:
 718                 retval = copy_to_user(argp, &joydev->glue,
 719                                       sizeof(joydev->glue)) ? -EFAULT : 0;
 720                 break;
 721
 722         default:
 723                 retval = joydev_ioctl_common(joydev, cmd, argp);
 724                 break;
 725         }
 726  out:
 727         mutex_unlock(&joydev->mutex);
 728         return retval;
 729 }
 730
 731 static const struct file_operations joydev_fops = {
 732         .owner          = THIS_MODULE,
 733         .read           = joydev_read,
 734         .poll           = joydev_poll,
 735         .open           = joydev_open,
 736         .release        = joydev_release,
 737         .unlocked_ioctl = joydev_ioctl,
 738 #ifdef CONFIG_COMPAT
 739         .compat_ioctl   = joydev_compat_ioctl,
 740 #endif
 741         .fasync         = joydev_fasync,
 742         .llseek         = no_llseek,
 743 };
 744
 745 static int joydev_install_chrdev(struct joydev *joydev)
 746 {
 747         joydev_table[joydev->minor] = joydev;
 748         return 0;
 749 }
 750
 751 static void joydev_remove_chrdev(struct joydev *joydev)
 752 {
 753         mutex_lock(&joydev_table_mutex);
 754         joydev_table[joydev->minor] = NULL;
 755         mutex_unlock(&joydev_table_mutex);
 756 }
 757
 758 /*
 759  * Mark device non-existent. This disables writes, ioctls and
 760  * prevents new users from opening the device. Already posted
 761  * blocking reads will stay, however new ones will fail.
 762  */
 763 static void joydev_mark_dead(struct joydev *joydev)
 764 {
 765         mutex_lock(&joydev->mutex);
 766         joydev->exist = false;
 767         mutex_unlock(&joydev->mutex);
 768 }
 769
 770 static void joydev_cleanup(struct joydev *joydev)
 771 {
 772         struct input_handle *handle = &joydev->handle;
 773
 774         joydev_mark_dead(joydev);
 775         joydev_hangup(joydev);
 776         joydev_remove_chrdev(joydev);
 777
 778         /* joydev is marked dead so no one else accesses joydev->open */
 779         if (joydev->open)
 780                 input_close_device(handle);
 781 }
 782
 783
 784 static bool joydev_match(struct input_handler *handler, struct input_dev *dev)
 785 {
 786         /* Avoid touchpads and touchscreens */
 787         if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_TOUCH, dev->keybit))
 788                 return false;
 789
 790         /* Avoid tablets, digitisers and similar devices */
 791         if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_DIGI, dev->keybit))
 792                 return false;
 793
 794         return true;
 795 }
 796
 797 static int joydev_connect(struct input_handler *handler, struct input_dev *dev,
 798                           const struct input_device_id *id)
 799 {
 800         struct joydev *joydev;
 801         int i, j, t, minor;
 802         int error;
 803
 804         for (minor = 0; minor < JOYDEV_MINORS; minor++)
 805                 if (!joydev_table[minor])
 806                         break;
 807
 808         if (minor == JOYDEV_MINORS) {
 809                 pr_err("no more free joydev devices\n");
 810                 return -ENFILE;
 811         }
 812
 813         joydev = kzalloc(sizeof(struct joydev), GFP_KERNEL);
 814         if (!joydev)
 815                 return -ENOMEM;
 816
 817         INIT_LIST_HEAD(&joydev->client_list);
 818         spin_lock_init(&joydev->client_lock);
 819         mutex_init(&joydev->mutex);
 820         init_waitqueue_head(&joydev->wait);
 821
 822         dev_set_name(&joydev->dev, "js%d", minor);
 823         joydev->exist = true;
 824         joydev->minor = minor;
 825
 826         joydev->handle.dev = input_get_device(dev);
 827         joydev->handle.name = dev_name(&joydev->dev);
 828         joydev->handle.handler = handler;
 829         joydev->handle.private = joydev;
 830
 831         for (i = 0; i < ABS_CNT; i++)
 832                 if (test_bit(i, dev->absbit)) {
 833                         joydev->absmap[i] = joydev->nabs;
 834                         joydev->abspam[joydev->nabs] = i;
 835                         joydev->nabs++;
 836                 }
 837
 838         for (i = BTN_JOYSTICK - BTN_MISC; i < KEY_MAX - BTN_MISC + 1; i++)
 839                 if (test_bit(i + BTN_MISC, dev->keybit)) {
 840                         joydev->keymap[i] = joydev->nkey;
 841                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
 842                         joydev->nkey++;
 843                 }
 844
 845         for (i = 0; i < BTN_JOYSTICK - BTN_MISC; i++)
 846                 if (test_bit(i + BTN_MISC, dev->keybit)) {
 847                         joydev->keymap[i] = joydev->nkey;
 848                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
 849                         joydev->nkey++;
 850                 }
 851
 852         for (i = 0; i < joydev->nabs; i++) {
 853                 j = joydev->abspam[i];
 854                 if (input_abs_get_max(dev, j) == input_abs_get_min(dev, j)) {
 855                         joydev->corr[i].type = JS_CORR_NONE;
 856                         joydev->abs[i] = input_abs_get_val(dev, j);
 857                         continue;
 858                 }
 859                 joydev->corr[i].type = JS_CORR_BROKEN;
 860                 joydev->corr[i].prec = input_abs_get_fuzz(dev, j);
 861
 862                 t = (input_abs_get_max(dev, j) + input_abs_get_min(dev, j)) / 2;
 863                 joydev->corr[i].coef[0] = t - input_abs_get_flat(dev, j);
 864                 joydev->corr[i].coef[1] = t + input_abs_get_flat(dev, j);
 865
 866                 t = (input_abs_get_max(dev, j) - input_abs_get_min(dev, j)) / 2
 867                         - 2 * input_abs_get_flat(dev, j);
 868                 if (t) {
 869                         joydev->corr[i].coef[2] = (1 << 29) / t;
 870                         joydev->corr[i].coef[3] = (1 << 29) / t;
 871
 872                         joydev->abs[i] =
 873                                 joydev_correct(input_abs_get_val(dev, j),
 874                                                joydev->corr + i);
 875                 }
 876         }
 877
 878         joydev->dev.devt = MKDEV(INPUT_MAJOR, JOYDEV_MINOR_BASE + minor);
 879         joydev->dev.class = &input_class;
 880         joydev->dev.parent = &dev->dev;
 881         joydev->dev.release = joydev_free;
 882         device_initialize(&joydev->dev);
 883
 884         error = input_register_handle(&joydev->handle);
 885         if (error)
 886                 goto err_free_joydev;
 887
 888         error = joydev_install_chrdev(joydev);
 889         if (error)
 890                 goto err_unregister_handle;
 891
 892         error = device_add(&joydev->dev);
 893         if (error)
 894                 goto err_cleanup_joydev;
 895
 896         return 0;
 897
 898  err_cleanup_joydev:
 899         joydev_cleanup(joydev);
 900  err_unregister_handle:
 901         input_unregister_handle(&joydev->handle);
 902  err_free_joydev:
 903         put_device(&joydev->dev);
 904         return error;
 905 }
 906
 907 static void joydev_disconnect(struct input_handle *handle)
 908 {
 909         struct joydev *joydev = handle->private;
 910
 911         device_del(&joydev->dev);
 912         joydev_cleanup(joydev);
 913         input_unregister_handle(handle);
 914         put_device(&joydev->dev);
 915 }
 916
 917 static const struct input_device_id joydev_ids[] = {
 918         {
 919                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 920                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 921                 .evbit = { BIT_MASK(EV_ABS) },
 922                 .absbit = { BIT_MASK(ABS_X) },
 923         },
 924         {
 925                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 926                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 927                 .evbit = { BIT_MASK(EV_ABS) },
 928                 .absbit = { BIT_MASK(ABS_WHEEL) },
 929         },
 930         {
 931                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 932                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 933                 .evbit = { BIT_MASK(EV_ABS) },
 934                 .absbit = { BIT_MASK(ABS_THROTTLE) },
 935         },
 936         {
 937                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 938                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
 939                 .evbit = { BIT_MASK(EV_KEY) },
 940                 .keybit = {[BIT_WORD(BTN_JOYSTICK)] = BIT_MASK(BTN_JOYSTICK) },
 941         },
 942         {
 943                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 944                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
 945                 .evbit = { BIT_MASK(EV_KEY) },
 946                 .keybit = { [BIT_WORD(BTN_GAMEPAD)] = BIT_MASK(BTN_GAMEPAD) },
 947         },
 948         {
 949                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 950                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
 951                 .evbit = { BIT_MASK(EV_KEY) },
 952                 .keybit = { [BIT_WORD(BTN_TRIGGER_HAPPY)] = BIT_MASK(BTN_TRIGGER_HAPPY) },
 953         },
 954         { }     /* Terminating entry */
 955 };
 956
 957 MODULE_DEVICE_TABLE(input, joydev_ids);
 958
 959 static struct input_handler joydev_handler = {
 960         .event          = joydev_event,
 961         .match          = joydev_match,
 962         .connect        = joydev_connect,
 963         .disconnect     = joydev_disconnect,
 964         .fops           = &joydev_fops,
 965         .minor          = JOYDEV_MINOR_BASE,
 966         .name           = "joydev",
 967         .id_table       = joydev_ids,
 968 };
 969
 970 static int __init joydev_init(void)
 971 {
 972         return input_register_handler(&joydev_handler);
 973 }
 974
 975 static void __exit joydev_exit(void)
 976 {
 977         input_unregister_handler(&joydev_handler);
 978 }
 979
 980 module_init(joydev_init);
 981 module_exit(joydev_exit);