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 <asm/system.h>
  17 #include <linux/delay.h>
  18 #include <linux/errno.h>
  19 #include <linux/joystick.h>
  20 #include <linux/input.h>
  21 #include <linux/kernel.h>
  22 #include <linux/major.h>
  23 #include <linux/sched.h>
  24 #include <linux/slab.h>
  25 #include <linux/mm.h>
  26 #include <linux/miscdevice.h>
  27 #include <linux/module.h>
  28 #include <linux/poll.h>
  29 #include <linux/init.h>
  30 #include <linux/device.h>
  31
  32 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
  33 MODULE_DESCRIPTION("Joystick device interfaces");
  34 MODULE_SUPPORTED_DEVICE("input/js");
  35 MODULE_LICENSE("GPL");
  36
  37 #define JOYDEV_MINOR_BASE       0
  38 #define JOYDEV_MINORS           16
  39 #define JOYDEV_BUFFER_SIZE      64
  40
  41 struct joydev {
  42         int open;
  43         int minor;
  44         struct input_handle handle;
  45         wait_queue_head_t wait;
  46         struct list_head client_list;
  47         spinlock_t client_lock; /* protects client_list */
  48         struct mutex mutex;
  49         struct device dev;
  50         bool exist;
  51
  52         struct js_corr corr[ABS_CNT];
  53         struct JS_DATA_SAVE_TYPE glue;
  54         int nabs;
  55         int nkey;
  56         __u16 keymap[KEY_MAX - BTN_MISC + 1];
  57         __u16 keypam[KEY_MAX - BTN_MISC + 1];
  58         __u8 absmap[ABS_CNT];
  59         __u8 abspam[ABS_CNT];
  60         __s16 abs[ABS_CNT];
  61 };
  62
  63 struct joydev_client {
  64         struct js_event buffer[JOYDEV_BUFFER_SIZE];
  65         int head;
  66         int tail;
  67         int startup;
  68         spinlock_t buffer_lock; /* protects access to buffer, head and tail */
  69         struct fasync_struct *fasync;
  70         struct joydev *joydev;
  71         struct list_head node;
  72 };
  73
  74 static struct joydev *joydev_table[JOYDEV_MINORS];
  75 static DEFINE_MUTEX(joydev_table_mutex);
  76
  77 static int joydev_correct(int value, struct js_corr *corr)
  78 {
  79         switch (corr->type) {
  80
  81         case JS_CORR_NONE:
  82                 break;
  83
  84         case JS_CORR_BROKEN:
  85                 value = value > corr->coef[0] ? (value < corr->coef[1] ? 0 :
  86                         ((corr->coef[3] * (value - corr->coef[1])) >> 14)) :
  87                         ((corr->coef[2] * (value - corr->coef[0])) >> 14);
  88                 break;
  89
  90         default:
  91                 return 0;
  92         }
  93
  94         return value < -32767 ? -32767 : (value > 32767 ? 32767 : value);
  95 }
  96
  97 static void joydev_pass_event(struct joydev_client *client,
  98                               struct js_event *event)
  99 {
 100         struct joydev *joydev = client->joydev;
 101
 102         /*
 103          * IRQs already disabled, just acquire the lock
 104          */
 105         spin_lock(&client->buffer_lock);
 106
 107         client->buffer[client->head] = *event;
 108
 109         if (client->startup == joydev->nabs + joydev->nkey) {
 110                 client->head++;
 111                 client->head &= JOYDEV_BUFFER_SIZE - 1;
 112                 if (client->tail == client->head)
 113                         client->startup = 0;
 114         }
 115
 116         spin_unlock(&client->buffer_lock);
 117
 118         kill_fasync(&client->fasync, SIGIO, POLL_IN);
 119 }
 120
 121 static void joydev_event(struct input_handle *handle,
 122                          unsigned int type, unsigned int code, int value)
 123 {
 124         struct joydev *joydev = handle->private;
 125         struct joydev_client *client;
 126         struct js_event event;
 127
 128         switch (type) {
 129
 130         case EV_KEY:
 131                 if (code < BTN_MISC || value == 2)
 132                         return;
 133                 event.type = JS_EVENT_BUTTON;
 134                 event.number = joydev->keymap[code - BTN_MISC];
 135                 event.value = value;
 136                 break;
 137
 138         case EV_ABS:
 139                 event.type = JS_EVENT_AXIS;
 140                 event.number = joydev->absmap[code];
 141                 event.value = joydev_correct(value,
 142                                         &joydev->corr[event.number]);
 143                 if (event.value == joydev->abs[event.number])
 144                         return;
 145                 joydev->abs[event.number] = event.value;
 146                 break;
 147
 148         default:
 149                 return;
 150         }
 151
 152         event.time = jiffies_to_msecs(jiffies);
 153
 154         rcu_read_lock();
 155         list_for_each_entry_rcu(client, &joydev->client_list, node)
 156                 joydev_pass_event(client, &event);
 157         rcu_read_unlock();
 158
 159         wake_up_interruptible(&joydev->wait);
 160 }
 161
 162 static int joydev_fasync(int fd, struct file *file, int on)
 163 {
 164         struct joydev_client *client = file->private_data;
 165
 166         return fasync_helper(fd, file, on, &client->fasync);
 167 }
 168
 169 static void joydev_free(struct device *dev)
 170 {
 171         struct joydev *joydev = container_of(dev, struct joydev, dev);
 172
 173         input_put_device(joydev->handle.dev);
 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_detach_client(joydev, client);
 247         kfree(client);
 248
 249         joydev_close_device(joydev);
 250         put_device(&joydev->dev);
 251
 252         return 0;
 253 }
 254
 255 static int joydev_open(struct inode *inode, struct file *file)
 256 {
 257         struct joydev_client *client;
 258         struct joydev *joydev;
 259         int i = iminor(inode) - JOYDEV_MINOR_BASE;
 260         int error;
 261
 262         if (i >= JOYDEV_MINORS)
 263                 return -ENODEV;
 264
 265         error = mutex_lock_interruptible(&joydev_table_mutex);
 266         if (error)
 267                 return error;
 268         joydev = joydev_table[i];
 269         if (joydev)
 270                 get_device(&joydev->dev);
 271         mutex_unlock(&joydev_table_mutex);
 272
 273         if (!joydev)
 274                 return -ENODEV;
 275
 276         client = kzalloc(sizeof(struct joydev_client), GFP_KERNEL);
 277         if (!client) {
 278                 error = -ENOMEM;
 279                 goto err_put_joydev;
 280         }
 281
 282         spin_lock_init(&client->buffer_lock);
 283         client->joydev = joydev;
 284         joydev_attach_client(joydev, client);
 285
 286         error = joydev_open_device(joydev);
 287         if (error)
 288                 goto err_free_client;
 289
 290         file->private_data = client;
 291         nonseekable_open(inode, file);
 292
 293         return 0;
 294
 295  err_free_client:
 296         joydev_detach_client(joydev, client);
 297         kfree(client);
 298  err_put_joydev:
 299         put_device(&joydev->dev);
 300         return error;
 301 }
 302
 303 static int joydev_generate_startup_event(struct joydev_client *client,
 304                                          struct input_dev *input,
 305                                          struct js_event *event)
 306 {
 307         struct joydev *joydev = client->joydev;
 308         int have_event;
 309
 310         spin_lock_irq(&client->buffer_lock);
 311
 312         have_event = client->startup < joydev->nabs + joydev->nkey;
 313
 314         if (have_event) {
 315
 316                 event->time = jiffies_to_msecs(jiffies);
 317                 if (client->startup < joydev->nkey) {
 318                         event->type = JS_EVENT_BUTTON | JS_EVENT_INIT;
 319                         event->number = client->startup;
 320                         event->value = !!test_bit(joydev->keypam[event->number],
 321                                                   input->key);
 322                 } else {
 323                         event->type = JS_EVENT_AXIS | JS_EVENT_INIT;
 324                         event->number = client->startup - joydev->nkey;
 325                         event->value = joydev->abs[event->number];
 326                 }
 327                 client->startup++;
 328         }
 329
 330         spin_unlock_irq(&client->buffer_lock);
 331
 332         return have_event;
 333 }
 334
 335 static int joydev_fetch_next_event(struct joydev_client *client,
 336                                    struct js_event *event)
 337 {
 338         int have_event;
 339
 340         spin_lock_irq(&client->buffer_lock);
 341
 342         have_event = client->head != client->tail;
 343         if (have_event) {
 344                 *event = client->buffer[client->tail++];
 345                 client->tail &= JOYDEV_BUFFER_SIZE - 1;
 346         }
 347
 348         spin_unlock_irq(&client->buffer_lock);
 349
 350         return have_event;
 351 }
 352
 353 /*
 354  * Old joystick interface
 355  */
 356 static ssize_t joydev_0x_read(struct joydev_client *client,
 357                               struct input_dev *input,
 358                               char __user *buf)
 359 {
 360         struct joydev *joydev = client->joydev;
 361         struct JS_DATA_TYPE data;
 362         int i;
 363
 364         spin_lock_irq(&input->event_lock);
 365
 366         /*
 367          * Get device state
 368          */
 369         for (data.buttons = i = 0; i < 32 && i < joydev->nkey; i++)
 370                 data.buttons |=
 371                         test_bit(joydev->keypam[i], input->key) ? (1 << i) : 0;
 372         data.x = (joydev->abs[0] / 256 + 128) >> joydev->glue.JS_CORR.x;
 373         data.y = (joydev->abs[1] / 256 + 128) >> joydev->glue.JS_CORR.y;
 374
 375         /*
 376          * Reset reader's event queue
 377          */
 378         spin_lock(&client->buffer_lock);
 379         client->startup = 0;
 380         client->tail = client->head;
 381         spin_unlock(&client->buffer_lock);
 382
 383         spin_unlock_irq(&input->event_lock);
 384
 385         if (copy_to_user(buf, &data, sizeof(struct JS_DATA_TYPE)))
 386                 return -EFAULT;
 387
 388         return sizeof(struct JS_DATA_TYPE);
 389 }
 390
 391 static inline int joydev_data_pending(struct joydev_client *client)
 392 {
 393         struct joydev *joydev = client->joydev;
 394
 395         return client->startup < joydev->nabs + joydev->nkey ||
 396                 client->head != client->tail;
 397 }
 398
 399 static ssize_t joydev_read(struct file *file, char __user *buf,
 400                            size_t count, loff_t *ppos)
 401 {
 402         struct joydev_client *client = file->private_data;
 403         struct joydev *joydev = client->joydev;
 404         struct input_dev *input = joydev->handle.dev;
 405         struct js_event event;
 406         int retval;
 407
 408         if (!joydev->exist)
 409                 return -ENODEV;
 410
 411         if (count < sizeof(struct js_event))
 412                 return -EINVAL;
 413
 414         if (count == sizeof(struct JS_DATA_TYPE))
 415                 return joydev_0x_read(client, input, buf);
 416
 417         if (!joydev_data_pending(client) && (file->f_flags & O_NONBLOCK))
 418                 return -EAGAIN;
 419
 420         retval = wait_event_interruptible(joydev->wait,
 421                         !joydev->exist || joydev_data_pending(client));
 422         if (retval)
 423                 return retval;
 424
 425         if (!joydev->exist)
 426                 return -ENODEV;
 427
 428         while (retval + sizeof(struct js_event) <= count &&
 429                joydev_generate_startup_event(client, input, &event)) {
 430
 431                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
 432                         return -EFAULT;
 433
 434                 retval += sizeof(struct js_event);
 435         }
 436
 437         while (retval + sizeof(struct js_event) <= count &&
 438                joydev_fetch_next_event(client, &event)) {
 439
 440                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
 441                         return -EFAULT;
 442
 443                 retval += sizeof(struct js_event);
 444         }
 445
 446         return retval;
 447 }
 448
 449 /* No kernel lock - fine */
 450 static unsigned int joydev_poll(struct file *file, poll_table *wait)
 451 {
 452         struct joydev_client *client = file->private_data;
 453         struct joydev *joydev = client->joydev;
 454
 455         poll_wait(file, &joydev->wait, wait);
 456         return (joydev_data_pending(client) ? (POLLIN | POLLRDNORM) : 0) |
 457                 (joydev->exist ?  0 : (POLLHUP | POLLERR));
 458 }
 459
 460 static int joydev_handle_JSIOCSAXMAP(struct joydev *joydev,
 461                                      void __user *argp, size_t len)
 462 {
 463         __u8 *abspam;
 464         int i;
 465         int retval = 0;
 466
 467         len = min(len, sizeof(joydev->abspam));
 468
 469         /* Validate the map. */
 470         abspam = kmalloc(len, GFP_KERNEL);
 471         if (!abspam)
 472                 return -ENOMEM;
 473
 474         if (copy_from_user(abspam, argp, len)) {
 475                 retval = -EFAULT;
 476                 goto out;
 477         }
 478
 479         for (i = 0; i < joydev->nabs; i++) {
 480                 if (abspam[i] > ABS_MAX) {
 481                         retval = -EINVAL;
 482                         goto out;
 483                 }
 484         }
 485
 486         memcpy(joydev->abspam, abspam, len);
 487
 488         for (i = 0; i < joydev->nabs; i++)
 489                 joydev->absmap[joydev->abspam[i]] = i;
 490
 491  out:
 492         kfree(abspam);
 493         return retval;
 494 }
 495
 496 static int joydev_handle_JSIOCSBTNMAP(struct joydev *joydev,
 497                                       void __user *argp, size_t len)
 498 {
 499         __u16 *keypam;
 500         int i;
 501         int retval = 0;
 502
 503         len = min(len, sizeof(joydev->keypam));
 504
 505         /* Validate the map. */
 506         keypam = kmalloc(len, GFP_KERNEL);
 507         if (!keypam)
 508                 return -ENOMEM;
 509
 510         if (copy_from_user(keypam, argp, len)) {
 511                 retval = -EFAULT;
 512                 goto out;
 513         }
 514
 515         for (i = 0; i < joydev->nkey; i++) {
 516                 if (keypam[i] > KEY_MAX || keypam[i] < BTN_MISC) {
 517                         retval = -EINVAL;
 518                         goto out;
 519                 }
 520         }
 521
 522         memcpy(joydev->keypam, keypam, len);
 523
 524         for (i = 0; i < joydev->nkey; i++)
 525                 joydev->keymap[keypam[i] - BTN_MISC] = i;
 526
 527  out:
 528         kfree(keypam);
 529         return retval;
 530 }
 531
 532
 533 static int joydev_ioctl_common(struct joydev *joydev,
 534                                 unsigned int cmd, void __user *argp)
 535 {
 536         struct input_dev *dev = joydev->handle.dev;
 537         size_t len;
 538         int i;
 539         const char *name;
 540
 541         /* Process fixed-sized commands. */
 542         switch (cmd) {
 543
 544         case JS_SET_CAL:
 545                 return copy_from_user(&joydev->glue.JS_CORR, argp,
 546                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
 547
 548         case JS_GET_CAL:
 549                 return copy_to_user(argp, &joydev->glue.JS_CORR,
 550                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
 551
 552         case JS_SET_TIMEOUT:
 553                 return get_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
 554
 555         case JS_GET_TIMEOUT:
 556                 return put_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
 557
 558         case JSIOCGVERSION:
 559                 return put_user(JS_VERSION, (__u32 __user *) argp);
 560
 561         case JSIOCGAXES:
 562                 return put_user(joydev->nabs, (__u8 __user *) argp);
 563
 564         case JSIOCGBUTTONS:
 565                 return put_user(joydev->nkey, (__u8 __user *) argp);
 566
 567         case JSIOCSCORR:
 568                 if (copy_from_user(joydev->corr, argp,
 569                               sizeof(joydev->corr[0]) * joydev->nabs))
 570                         return -EFAULT;
 571
 572                 for (i = 0; i < joydev->nabs; i++) {
 573                         int val = input_abs_get_val(dev, joydev->abspam[i]);
 574                         joydev->abs[i] = joydev_correct(val, &joydev->corr[i]);
 575                 }
 576                 return 0;
 577
 578         case JSIOCGCORR:
 579                 return copy_to_user(argp, joydev->corr,
 580                         sizeof(joydev->corr[0]) * joydev->nabs) ? -EFAULT : 0;
 581
 582         }
 583
 584         /*
 585          * Process variable-sized commands (the axis and button map commands
 586          * are considered variable-sized to decouple them from the values of
 587          * ABS_MAX and KEY_MAX).
 588          */
 589         switch (cmd & ~IOCSIZE_MASK) {
 590
 591         case (JSIOCSAXMAP & ~IOCSIZE_MASK):
 592                 return joydev_handle_JSIOCSAXMAP(joydev, argp, _IOC_SIZE(cmd));
 593
 594         case (JSIOCGAXMAP & ~IOCSIZE_MASK):
 595                 len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->abspam));
 596                 return copy_to_user(argp, joydev->abspam, len) ? -EFAULT : len;
 597
 598         case (JSIOCSBTNMAP & ~IOCSIZE_MASK):
 599                 return joydev_handle_JSIOCSBTNMAP(joydev, argp, _IOC_SIZE(cmd));
 600
 601         case (JSIOCGBTNMAP & ~IOCSIZE_MASK):
 602                 len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->keypam));
 603                 return copy_to_user(argp, joydev->keypam, len) ? -EFAULT : len;
 604
 605         case JSIOCGNAME(0):
 606                 name = dev->name;
 607                 if (!name)
 608                         return 0;
 609
 610                 len = min_t(size_t, _IOC_SIZE(cmd), strlen(name) + 1);
 611                 return copy_to_user(argp, name, len) ? -EFAULT : len;
 612         }
 613
 614         return -EINVAL;
 615 }
 616
 617 #ifdef CONFIG_COMPAT
 618 static long joydev_compat_ioctl(struct file *file,
 619                                 unsigned int cmd, unsigned long arg)
 620 {
 621         struct joydev_client *client = file->private_data;
 622         struct joydev *joydev = client->joydev;
 623         void __user *argp = (void __user *)arg;
 624         s32 tmp32;
 625         struct JS_DATA_SAVE_TYPE_32 ds32;
 626         int retval;
 627
 628         retval = mutex_lock_interruptible(&joydev->mutex);
 629         if (retval)
 630                 return retval;
 631
 632         if (!joydev->exist) {
 633                 retval = -ENODEV;
 634                 goto out;
 635         }
 636
 637         switch (cmd) {
 638
 639         case JS_SET_TIMELIMIT:
 640                 retval = get_user(tmp32, (s32 __user *) arg);
 641                 if (retval == 0)
 642                         joydev->glue.JS_TIMELIMIT = tmp32;
 643                 break;
 644
 645         case JS_GET_TIMELIMIT:
 646                 tmp32 = joydev->glue.JS_TIMELIMIT;
 647                 retval = put_user(tmp32, (s32 __user *) arg);
 648                 break;
 649
 650         case JS_SET_ALL:
 651                 retval = copy_from_user(&ds32, argp,
 652                                         sizeof(ds32)) ? -EFAULT : 0;
 653                 if (retval == 0) {
 654                         joydev->glue.JS_TIMEOUT    = ds32.JS_TIMEOUT;
 655                         joydev->glue.BUSY          = ds32.BUSY;
 656                         joydev->glue.JS_EXPIRETIME = ds32.JS_EXPIRETIME;
 657                         joydev->glue.JS_TIMELIMIT  = ds32.JS_TIMELIMIT;
 658                         joydev->glue.JS_SAVE       = ds32.JS_SAVE;
 659                         joydev->glue.JS_CORR       = ds32.JS_CORR;
 660                 }
 661                 break;
 662
 663         case JS_GET_ALL:
 664                 ds32.JS_TIMEOUT    = joydev->glue.JS_TIMEOUT;
 665                 ds32.BUSY          = joydev->glue.BUSY;
 666                 ds32.JS_EXPIRETIME = joydev->glue.JS_EXPIRETIME;
 667                 ds32.JS_TIMELIMIT  = joydev->glue.JS_TIMELIMIT;
 668                 ds32.JS_SAVE       = joydev->glue.JS_SAVE;
 669                 ds32.JS_CORR       = joydev->glue.JS_CORR;
 670
 671                 retval = copy_to_user(argp, &ds32, sizeof(ds32)) ? -EFAULT : 0;
 672                 break;
 673
 674         default:
 675                 retval = joydev_ioctl_common(joydev, cmd, argp);
 676                 break;
 677         }
 678
 679  out:
 680         mutex_unlock(&joydev->mutex);
 681         return retval;
 682 }
 683 #endif /* CONFIG_COMPAT */
 684
 685 static long joydev_ioctl(struct file *file,
 686                          unsigned int cmd, unsigned long arg)
 687 {
 688         struct joydev_client *client = file->private_data;
 689         struct joydev *joydev = client->joydev;
 690         void __user *argp = (void __user *)arg;
 691         int retval;
 692
 693         retval = mutex_lock_interruptible(&joydev->mutex);
 694         if (retval)
 695                 return retval;
 696
 697         if (!joydev->exist) {
 698                 retval = -ENODEV;
 699                 goto out;
 700         }
 701
 702         switch (cmd) {
 703
 704         case JS_SET_TIMELIMIT:
 705                 retval = get_user(joydev->glue.JS_TIMELIMIT,
 706                                   (long __user *) arg);
 707                 break;
 708
 709         case JS_GET_TIMELIMIT:
 710                 retval = put_user(joydev->glue.JS_TIMELIMIT,
 711                                   (long __user *) arg);
 712                 break;
 713
 714         case JS_SET_ALL:
 715                 retval = copy_from_user(&joydev->glue, argp,
 716                                         sizeof(joydev->glue)) ? -EFAULT: 0;
 717                 break;
 718
 719         case JS_GET_ALL:
 720                 retval = copy_to_user(argp, &joydev->glue,
 721                                       sizeof(joydev->glue)) ? -EFAULT : 0;
 722                 break;
 723
 724         default:
 725                 retval = joydev_ioctl_common(joydev, cmd, argp);
 726                 break;
 727         }
 728  out:
 729         mutex_unlock(&joydev->mutex);
 730         return retval;
 731 }
 732
 733 static const struct file_operations joydev_fops = {
 734         .owner          = THIS_MODULE,
 735         .read           = joydev_read,
 736         .poll           = joydev_poll,
 737         .open           = joydev_open,
 738         .release        = joydev_release,
 739         .unlocked_ioctl = joydev_ioctl,
 740 #ifdef CONFIG_COMPAT
 741         .compat_ioctl   = joydev_compat_ioctl,
 742 #endif
 743         .fasync         = joydev_fasync,
 744         .llseek         = no_llseek,
 745 };
 746
 747 static int joydev_install_chrdev(struct joydev *joydev)
 748 {
 749         joydev_table[joydev->minor] = joydev;
 750         return 0;
 751 }
 752
 753 static void joydev_remove_chrdev(struct joydev *joydev)
 754 {
 755         mutex_lock(&joydev_table_mutex);
 756         joydev_table[joydev->minor] = NULL;
 757         mutex_unlock(&joydev_table_mutex);
 758 }
 759
 760 /*
 761  * Mark device non-existent. This disables writes, ioctls and
 762  * prevents new users from opening the device. Already posted
 763  * blocking reads will stay, however new ones will fail.
 764  */
 765 static void joydev_mark_dead(struct joydev *joydev)
 766 {
 767         mutex_lock(&joydev->mutex);
 768         joydev->exist = false;
 769         mutex_unlock(&joydev->mutex);
 770 }
 771
 772 static void joydev_cleanup(struct joydev *joydev)
 773 {
 774         struct input_handle *handle = &joydev->handle;
 775
 776         joydev_mark_dead(joydev);
 777         joydev_hangup(joydev);
 778         joydev_remove_chrdev(joydev);
 779
 780         /* joydev is marked dead so no one else accesses joydev->open */
 781         if (joydev->open)
 782                 input_close_device(handle);
 783 }
 784
 785
 786 static bool joydev_match(struct input_handler *handler, struct input_dev *dev)
 787 {
 788         /* Avoid touchpads and touchscreens */
 789         if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_TOUCH, dev->keybit))
 790                 return false;
 791
 792         /* Avoid tablets, digitisers and similar devices */
 793         if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_DIGI, dev->keybit))
 794                 return false;
 795
 796         return true;
 797 }
 798
 799 static int joydev_connect(struct input_handler *handler, struct input_dev *dev,
 800                           const struct input_device_id *id)
 801 {
 802         struct joydev *joydev;
 803         int i, j, t, minor;
 804         int error;
 805
 806         for (minor = 0; minor < JOYDEV_MINORS; minor++)
 807                 if (!joydev_table[minor])
 808                         break;
 809
 810         if (minor == JOYDEV_MINORS) {
 811                 pr_err("no more free joydev devices\n");
 812                 return -ENFILE;
 813         }
 814
 815         joydev = kzalloc(sizeof(struct joydev), GFP_KERNEL);
 816         if (!joydev)
 817                 return -ENOMEM;
 818
 819         INIT_LIST_HEAD(&joydev->client_list);
 820         spin_lock_init(&joydev->client_lock);
 821         mutex_init(&joydev->mutex);
 822         init_waitqueue_head(&joydev->wait);
 823
 824         dev_set_name(&joydev->dev, "js%d", minor);
 825         joydev->exist = true;
 826         joydev->minor = minor;
 827
 828         joydev->handle.dev = input_get_device(dev);
 829         joydev->handle.name = dev_name(&joydev->dev);
 830         joydev->handle.handler = handler;
 831         joydev->handle.private = joydev;
 832
 833         for (i = 0; i < ABS_CNT; i++)
 834                 if (test_bit(i, dev->absbit)) {
 835                         joydev->absmap[i] = joydev->nabs;
 836                         joydev->abspam[joydev->nabs] = i;
 837                         joydev->nabs++;
 838                 }
 839
 840         for (i = BTN_JOYSTICK - BTN_MISC; i < KEY_MAX - BTN_MISC + 1; i++)
 841                 if (test_bit(i + BTN_MISC, dev->keybit)) {
 842                         joydev->keymap[i] = joydev->nkey;
 843                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
 844                         joydev->nkey++;
 845                 }
 846
 847         for (i = 0; i < BTN_JOYSTICK - BTN_MISC; i++)
 848                 if (test_bit(i + BTN_MISC, dev->keybit)) {
 849                         joydev->keymap[i] = joydev->nkey;
 850                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
 851                         joydev->nkey++;
 852                 }
 853
 854         for (i = 0; i < joydev->nabs; i++) {
 855                 j = joydev->abspam[i];
 856                 if (input_abs_get_max(dev, j) == input_abs_get_min(dev, j)) {
 857                         joydev->corr[i].type = JS_CORR_NONE;
 858                         joydev->abs[i] = input_abs_get_val(dev, j);
 859                         continue;
 860                 }
 861                 joydev->corr[i].type = JS_CORR_BROKEN;
 862                 joydev->corr[i].prec = input_abs_get_fuzz(dev, j);
 863
 864                 t = (input_abs_get_max(dev, j) + input_abs_get_min(dev, j)) / 2;
 865                 joydev->corr[i].coef[0] = t - input_abs_get_flat(dev, j);
 866                 joydev->corr[i].coef[1] = t + input_abs_get_flat(dev, j);
 867
 868                 t = (input_abs_get_max(dev, j) - input_abs_get_min(dev, j)) / 2
 869                         - 2 * input_abs_get_flat(dev, j);
 870                 if (t) {
 871                         joydev->corr[i].coef[2] = (1 << 29) / t;
 872                         joydev->corr[i].coef[3] = (1 << 29) / t;
 873
 874                         joydev->abs[i] =
 875                                 joydev_correct(input_abs_get_val(dev, j),
 876                                                joydev->corr + i);
 877                 }
 878         }
 879
 880         joydev->dev.devt = MKDEV(INPUT_MAJOR, JOYDEV_MINOR_BASE + minor);
 881         joydev->dev.class = &input_class;
 882         joydev->dev.parent = &dev->dev;
 883         joydev->dev.release = joydev_free;
 884         device_initialize(&joydev->dev);
 885
 886         error = input_register_handle(&joydev->handle);
 887         if (error)
 888                 goto err_free_joydev;
 889
 890         error = joydev_install_chrdev(joydev);
 891         if (error)
 892                 goto err_unregister_handle;
 893
 894         error = device_add(&joydev->dev);
 895         if (error)
 896                 goto err_cleanup_joydev;
 897
 898         return 0;
 899
 900  err_cleanup_joydev:
 901         joydev_cleanup(joydev);
 902  err_unregister_handle:
 903         input_unregister_handle(&joydev->handle);
 904  err_free_joydev:
 905         put_device(&joydev->dev);
 906         return error;
 907 }
 908
 909 static void joydev_disconnect(struct input_handle *handle)
 910 {
 911         struct joydev *joydev = handle->private;
 912
 913         device_del(&joydev->dev);
 914         joydev_cleanup(joydev);
 915         input_unregister_handle(handle);
 916         put_device(&joydev->dev);
 917 }
 918
 919 static const struct input_device_id joydev_ids[] = {
 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_X) },
 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_WHEEL) },
 931         },
 932         {
 933                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 934                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 935                 .evbit = { BIT_MASK(EV_ABS) },
 936                 .absbit = { BIT_MASK(ABS_THROTTLE) },
 937         },
 938         {
 939                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 940                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
 941                 .evbit = { BIT_MASK(EV_KEY) },
 942                 .keybit = {[BIT_WORD(BTN_JOYSTICK)] = BIT_MASK(BTN_JOYSTICK) },
 943         },
 944         {
 945                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 946                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
 947                 .evbit = { BIT_MASK(EV_KEY) },
 948                 .keybit = { [BIT_WORD(BTN_GAMEPAD)] = BIT_MASK(BTN_GAMEPAD) },
 949         },
 950         {
 951                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 952                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
 953                 .evbit = { BIT_MASK(EV_KEY) },
 954                 .keybit = { [BIT_WORD(BTN_TRIGGER_HAPPY)] = BIT_MASK(BTN_TRIGGER_HAPPY) },
 955         },
 956         { }     /* Terminating entry */
 957 };
 958
 959 MODULE_DEVICE_TABLE(input, joydev_ids);
 960
 961 static struct input_handler joydev_handler = {
 962         .event          = joydev_event,
 963         .match          = joydev_match,
 964         .connect        = joydev_connect,
 965         .disconnect     = joydev_disconnect,
 966         .fops           = &joydev_fops,
 967         .minor          = JOYDEV_MINOR_BASE,
 968         .name           = "joydev",
 969         .id_table       = joydev_ids,
 970 };
 971
 972 static int __init joydev_init(void)
 973 {
 974         return input_register_handler(&joydev_handler);
 975 }
 976
 977 static void __exit joydev_exit(void)
 978 {
 979         input_unregister_handler(&joydev_handler);
 980 }
 981
 982 module_init(joydev_init);
 983 module_exit(joydev_exit);