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 }
 184
 185 static void joydev_detach_client(struct joydev *joydev,
 186                                  struct joydev_client *client)
 187 {
 188         spin_lock(&joydev->client_lock);
 189         list_del_rcu(&client->node);
 190         spin_unlock(&joydev->client_lock);
 191         synchronize_rcu();
 192 }
 193
 194 static int joydev_open_device(struct joydev *joydev)
 195 {
 196         int retval;
 197
 198         retval = mutex_lock_interruptible(&joydev->mutex);
 199         if (retval)
 200                 return retval;
 201
 202         if (!joydev->exist)
 203                 retval = -ENODEV;
 204         else if (!joydev->open++) {
 205                 retval = input_open_device(&joydev->handle);
 206                 if (retval)
 207                         joydev->open--;
 208         }
 209
 210         mutex_unlock(&joydev->mutex);
 211         return retval;
 212 }
 213
 214 static void joydev_close_device(struct joydev *joydev)
 215 {
 216         mutex_lock(&joydev->mutex);
 217
 218         if (joydev->exist && !--joydev->open)
 219                 input_close_device(&joydev->handle);
 220
 221         mutex_unlock(&joydev->mutex);
 222 }
 223
 224 /*
 225  * Wake up users waiting for IO so they can disconnect from
 226  * dead device.
 227  */
 228 static void joydev_hangup(struct joydev *joydev)
 229 {
 230         struct joydev_client *client;
 231
 232         spin_lock(&joydev->client_lock);
 233         list_for_each_entry(client, &joydev->client_list, node)
 234                 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
 235         spin_unlock(&joydev->client_lock);
 236
 237         wake_up_interruptible(&joydev->wait);
 238 }
 239
 240 static int joydev_release(struct inode *inode, struct file *file)
 241 {
 242         struct joydev_client *client = file->private_data;
 243         struct joydev *joydev = client->joydev;
 244
 245         joydev_detach_client(joydev, client);
 246         kfree(client);
 247
 248         joydev_close_device(joydev);
 249         put_device(&joydev->dev);
 250
 251         return 0;
 252 }
 253
 254 static int joydev_open(struct inode *inode, struct file *file)
 255 {
 256         struct joydev_client *client;
 257         struct joydev *joydev;
 258         int i = iminor(inode) - JOYDEV_MINOR_BASE;
 259         int error;
 260
 261         if (i >= JOYDEV_MINORS)
 262                 return -ENODEV;
 263
 264         error = mutex_lock_interruptible(&joydev_table_mutex);
 265         if (error)
 266                 return error;
 267         joydev = joydev_table[i];
 268         if (joydev)
 269                 get_device(&joydev->dev);
 270         mutex_unlock(&joydev_table_mutex);
 271
 272         if (!joydev)
 273                 return -ENODEV;
 274
 275         client = kzalloc(sizeof(struct joydev_client), GFP_KERNEL);
 276         if (!client) {
 277                 error = -ENOMEM;
 278                 goto err_put_joydev;
 279         }
 280
 281         spin_lock_init(&client->buffer_lock);
 282         client->joydev = joydev;
 283         joydev_attach_client(joydev, client);
 284
 285         error = joydev_open_device(joydev);
 286         if (error)
 287                 goto err_free_client;
 288
 289         file->private_data = client;
 290         nonseekable_open(inode, file);
 291
 292         return 0;
 293
 294  err_free_client:
 295         joydev_detach_client(joydev, client);
 296         kfree(client);
 297  err_put_joydev:
 298         put_device(&joydev->dev);
 299         return error;
 300 }
 301
 302 static int joydev_generate_startup_event(struct joydev_client *client,
 303                                          struct input_dev *input,
 304                                          struct js_event *event)
 305 {
 306         struct joydev *joydev = client->joydev;
 307         int have_event;
 308
 309         spin_lock_irq(&client->buffer_lock);
 310
 311         have_event = client->startup < joydev->nabs + joydev->nkey;
 312
 313         if (have_event) {
 314
 315                 event->time = jiffies_to_msecs(jiffies);
 316                 if (client->startup < joydev->nkey) {
 317                         event->type = JS_EVENT_BUTTON | JS_EVENT_INIT;
 318                         event->number = client->startup;
 319                         event->value = !!test_bit(joydev->keypam[event->number],
 320                                                   input->key);
 321                 } else {
 322                         event->type = JS_EVENT_AXIS | JS_EVENT_INIT;
 323                         event->number = client->startup - joydev->nkey;
 324                         event->value = joydev->abs[event->number];
 325                 }
 326                 client->startup++;
 327         }
 328
 329         spin_unlock_irq(&client->buffer_lock);
 330
 331         return have_event;
 332 }
 333
 334 static int joydev_fetch_next_event(struct joydev_client *client,
 335                                    struct js_event *event)
 336 {
 337         int have_event;
 338
 339         spin_lock_irq(&client->buffer_lock);
 340
 341         have_event = client->head != client->tail;
 342         if (have_event) {
 343                 *event = client->buffer[client->tail++];
 344                 client->tail &= JOYDEV_BUFFER_SIZE - 1;
 345         }
 346
 347         spin_unlock_irq(&client->buffer_lock);
 348
 349         return have_event;
 350 }
 351
 352 /*
 353  * Old joystick interface
 354  */
 355 static ssize_t joydev_0x_read(struct joydev_client *client,
 356                               struct input_dev *input,
 357                               char __user *buf)
 358 {
 359         struct joydev *joydev = client->joydev;
 360         struct JS_DATA_TYPE data;
 361         int i;
 362
 363         spin_lock_irq(&input->event_lock);
 364
 365         /*
 366          * Get device state
 367          */
 368         for (data.buttons = i = 0; i < 32 && i < joydev->nkey; i++)
 369                 data.buttons |=
 370                         test_bit(joydev->keypam[i], input->key) ? (1 << i) : 0;
 371         data.x = (joydev->abs[0] / 256 + 128) >> joydev->glue.JS_CORR.x;
 372         data.y = (joydev->abs[1] / 256 + 128) >> joydev->glue.JS_CORR.y;
 373
 374         /*
 375          * Reset reader's event queue
 376          */
 377         spin_lock(&client->buffer_lock);
 378         client->startup = 0;
 379         client->tail = client->head;
 380         spin_unlock(&client->buffer_lock);
 381
 382         spin_unlock_irq(&input->event_lock);
 383
 384         if (copy_to_user(buf, &data, sizeof(struct JS_DATA_TYPE)))
 385                 return -EFAULT;
 386
 387         return sizeof(struct JS_DATA_TYPE);
 388 }
 389
 390 static inline int joydev_data_pending(struct joydev_client *client)
 391 {
 392         struct joydev *joydev = client->joydev;
 393
 394         return client->startup < joydev->nabs + joydev->nkey ||
 395                 client->head != client->tail;
 396 }
 397
 398 static ssize_t joydev_read(struct file *file, char __user *buf,
 399                            size_t count, loff_t *ppos)
 400 {
 401         struct joydev_client *client = file->private_data;
 402         struct joydev *joydev = client->joydev;
 403         struct input_dev *input = joydev->handle.dev;
 404         struct js_event event;
 405         int retval;
 406
 407         if (!joydev->exist)
 408                 return -ENODEV;
 409
 410         if (count < sizeof(struct js_event))
 411                 return -EINVAL;
 412
 413         if (count == sizeof(struct JS_DATA_TYPE))
 414                 return joydev_0x_read(client, input, buf);
 415
 416         if (!joydev_data_pending(client) && (file->f_flags & O_NONBLOCK))
 417                 return -EAGAIN;
 418
 419         retval = wait_event_interruptible(joydev->wait,
 420                         !joydev->exist || joydev_data_pending(client));
 421         if (retval)
 422                 return retval;
 423
 424         if (!joydev->exist)
 425                 return -ENODEV;
 426
 427         while (retval + sizeof(struct js_event) <= count &&
 428                joydev_generate_startup_event(client, input, &event)) {
 429
 430                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
 431                         return -EFAULT;
 432
 433                 retval += sizeof(struct js_event);
 434         }
 435
 436         while (retval + sizeof(struct js_event) <= count &&
 437                joydev_fetch_next_event(client, &event)) {
 438
 439                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
 440                         return -EFAULT;
 441
 442                 retval += sizeof(struct js_event);
 443         }
 444
 445         return retval;
 446 }
 447
 448 /* No kernel lock - fine */
 449 static unsigned int joydev_poll(struct file *file, poll_table *wait)
 450 {
 451         struct joydev_client *client = file->private_data;
 452         struct joydev *joydev = client->joydev;
 453
 454         poll_wait(file, &joydev->wait, wait);
 455         return (joydev_data_pending(client) ? (POLLIN | POLLRDNORM) : 0) |
 456                 (joydev->exist ?  0 : (POLLHUP | POLLERR));
 457 }
 458
 459 static int joydev_handle_JSIOCSAXMAP(struct joydev *joydev,
 460                                      void __user *argp, size_t len)
 461 {
 462         __u8 *abspam;
 463         int i;
 464         int retval = 0;
 465
 466         len = min(len, sizeof(joydev->abspam));
 467
 468         /* Validate the map. */
 469         abspam = kmalloc(len, GFP_KERNEL);
 470         if (!abspam)
 471                 return -ENOMEM;
 472
 473         if (copy_from_user(abspam, argp, len)) {
 474                 retval = -EFAULT;
 475                 goto out;
 476         }
 477
 478         for (i = 0; i < joydev->nabs; i++) {
 479                 if (abspam[i] > ABS_MAX) {
 480                         retval = -EINVAL;
 481                         goto out;
 482                 }
 483         }
 484
 485         memcpy(joydev->abspam, abspam, len);
 486
 487         for (i = 0; i < joydev->nabs; i++)
 488                 joydev->absmap[joydev->abspam[i]] = i;
 489
 490  out:
 491         kfree(abspam);
 492         return retval;
 493 }
 494
 495 static int joydev_handle_JSIOCSBTNMAP(struct joydev *joydev,
 496                                       void __user *argp, size_t len)
 497 {
 498         __u16 *keypam;
 499         int i;
 500         int retval = 0;
 501
 502         len = min(len, sizeof(joydev->keypam));
 503
 504         /* Validate the map. */
 505         keypam = kmalloc(len, GFP_KERNEL);
 506         if (!keypam)
 507                 return -ENOMEM;
 508
 509         if (copy_from_user(keypam, argp, len)) {
 510                 retval = -EFAULT;
 511                 goto out;
 512         }
 513
 514         for (i = 0; i < joydev->nkey; i++) {
 515                 if (keypam[i] > KEY_MAX || keypam[i] < BTN_MISC) {
 516                         retval = -EINVAL;
 517                         goto out;
 518                 }
 519         }
 520
 521         memcpy(joydev->keypam, keypam, len);
 522
 523         for (i = 0; i < joydev->nkey; i++)
 524                 joydev->keymap[keypam[i] - BTN_MISC] = i;
 525
 526  out:
 527         kfree(keypam);
 528         return retval;
 529 }
 530
 531
 532 static int joydev_ioctl_common(struct joydev *joydev,
 533                                 unsigned int cmd, void __user *argp)
 534 {
 535         struct input_dev *dev = joydev->handle.dev;
 536         size_t len;
 537         int i;
 538         const char *name;
 539
 540         /* Process fixed-sized commands. */
 541         switch (cmd) {
 542
 543         case JS_SET_CAL:
 544                 return copy_from_user(&joydev->glue.JS_CORR, argp,
 545                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
 546
 547         case JS_GET_CAL:
 548                 return copy_to_user(argp, &joydev->glue.JS_CORR,
 549                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
 550
 551         case JS_SET_TIMEOUT:
 552                 return get_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
 553
 554         case JS_GET_TIMEOUT:
 555                 return put_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
 556
 557         case JSIOCGVERSION:
 558                 return put_user(JS_VERSION, (__u32 __user *) argp);
 559
 560         case JSIOCGAXES:
 561                 return put_user(joydev->nabs, (__u8 __user *) argp);
 562
 563         case JSIOCGBUTTONS:
 564                 return put_user(joydev->nkey, (__u8 __user *) argp);
 565
 566         case JSIOCSCORR:
 567                 if (copy_from_user(joydev->corr, argp,
 568                               sizeof(joydev->corr[0]) * joydev->nabs))
 569                         return -EFAULT;
 570
 571                 for (i = 0; i < joydev->nabs; i++) {
 572                         int val = input_abs_get_val(dev, joydev->abspam[i]);
 573                         joydev->abs[i] = joydev_correct(val, &joydev->corr[i]);
 574                 }
 575                 return 0;
 576
 577         case JSIOCGCORR:
 578                 return copy_to_user(argp, joydev->corr,
 579                         sizeof(joydev->corr[0]) * joydev->nabs) ? -EFAULT : 0;
 580
 581         }
 582
 583         /*
 584          * Process variable-sized commands (the axis and button map commands
 585          * are considered variable-sized to decouple them from the values of
 586          * ABS_MAX and KEY_MAX).
 587          */
 588         switch (cmd & ~IOCSIZE_MASK) {
 589
 590         case (JSIOCSAXMAP & ~IOCSIZE_MASK):
 591                 return joydev_handle_JSIOCSAXMAP(joydev, argp, _IOC_SIZE(cmd));
 592
 593         case (JSIOCGAXMAP & ~IOCSIZE_MASK):
 594                 len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->abspam));
 595                 return copy_to_user(argp, joydev->abspam, len) ? -EFAULT : len;
 596
 597         case (JSIOCSBTNMAP & ~IOCSIZE_MASK):
 598                 return joydev_handle_JSIOCSBTNMAP(joydev, argp, _IOC_SIZE(cmd));
 599
 600         case (JSIOCGBTNMAP & ~IOCSIZE_MASK):
 601                 len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->keypam));
 602                 return copy_to_user(argp, joydev->keypam, len) ? -EFAULT : len;
 603
 604         case JSIOCGNAME(0):
 605                 name = dev->name;
 606                 if (!name)
 607                         return 0;
 608
 609                 len = min_t(size_t, _IOC_SIZE(cmd), strlen(name) + 1);
 610                 return copy_to_user(argp, name, len) ? -EFAULT : len;
 611         }
 612
 613         return -EINVAL;
 614 }
 615
 616 #ifdef CONFIG_COMPAT
 617 static long joydev_compat_ioctl(struct file *file,
 618                                 unsigned int cmd, unsigned long arg)
 619 {
 620         struct joydev_client *client = file->private_data;
 621         struct joydev *joydev = client->joydev;
 622         void __user *argp = (void __user *)arg;
 623         s32 tmp32;
 624         struct JS_DATA_SAVE_TYPE_32 ds32;
 625         int retval;
 626
 627         retval = mutex_lock_interruptible(&joydev->mutex);
 628         if (retval)
 629                 return retval;
 630
 631         if (!joydev->exist) {
 632                 retval = -ENODEV;
 633                 goto out;
 634         }
 635
 636         switch (cmd) {
 637
 638         case JS_SET_TIMELIMIT:
 639                 retval = get_user(tmp32, (s32 __user *) arg);
 640                 if (retval == 0)
 641                         joydev->glue.JS_TIMELIMIT = tmp32;
 642                 break;
 643
 644         case JS_GET_TIMELIMIT:
 645                 tmp32 = joydev->glue.JS_TIMELIMIT;
 646                 retval = put_user(tmp32, (s32 __user *) arg);
 647                 break;
 648
 649         case JS_SET_ALL:
 650                 retval = copy_from_user(&ds32, argp,
 651                                         sizeof(ds32)) ? -EFAULT : 0;
 652                 if (retval == 0) {
 653                         joydev->glue.JS_TIMEOUT    = ds32.JS_TIMEOUT;
 654                         joydev->glue.BUSY          = ds32.BUSY;
 655                         joydev->glue.JS_EXPIRETIME = ds32.JS_EXPIRETIME;
 656                         joydev->glue.JS_TIMELIMIT  = ds32.JS_TIMELIMIT;
 657                         joydev->glue.JS_SAVE       = ds32.JS_SAVE;
 658                         joydev->glue.JS_CORR       = ds32.JS_CORR;
 659                 }
 660                 break;
 661
 662         case JS_GET_ALL:
 663                 ds32.JS_TIMEOUT    = joydev->glue.JS_TIMEOUT;
 664                 ds32.BUSY          = joydev->glue.BUSY;
 665                 ds32.JS_EXPIRETIME = joydev->glue.JS_EXPIRETIME;
 666                 ds32.JS_TIMELIMIT  = joydev->glue.JS_TIMELIMIT;
 667                 ds32.JS_SAVE       = joydev->glue.JS_SAVE;
 668                 ds32.JS_CORR       = joydev->glue.JS_CORR;
 669
 670                 retval = copy_to_user(argp, &ds32, sizeof(ds32)) ? -EFAULT : 0;
 671                 break;
 672
 673         default:
 674                 retval = joydev_ioctl_common(joydev, cmd, argp);
 675                 break;
 676         }
 677
 678  out:
 679         mutex_unlock(&joydev->mutex);
 680         return retval;
 681 }
 682 #endif /* CONFIG_COMPAT */
 683
 684 static long joydev_ioctl(struct file *file,
 685                          unsigned int cmd, unsigned long arg)
 686 {
 687         struct joydev_client *client = file->private_data;
 688         struct joydev *joydev = client->joydev;
 689         void __user *argp = (void __user *)arg;
 690         int retval;
 691
 692         retval = mutex_lock_interruptible(&joydev->mutex);
 693         if (retval)
 694                 return retval;
 695
 696         if (!joydev->exist) {
 697                 retval = -ENODEV;
 698                 goto out;
 699         }
 700
 701         switch (cmd) {
 702
 703         case JS_SET_TIMELIMIT:
 704                 retval = get_user(joydev->glue.JS_TIMELIMIT,
 705                                   (long __user *) arg);
 706                 break;
 707
 708         case JS_GET_TIMELIMIT:
 709                 retval = put_user(joydev->glue.JS_TIMELIMIT,
 710                                   (long __user *) arg);
 711                 break;
 712
 713         case JS_SET_ALL:
 714                 retval = copy_from_user(&joydev->glue, argp,
 715                                         sizeof(joydev->glue)) ? -EFAULT: 0;
 716                 break;
 717
 718         case JS_GET_ALL:
 719                 retval = copy_to_user(argp, &joydev->glue,
 720                                       sizeof(joydev->glue)) ? -EFAULT : 0;
 721                 break;
 722
 723         default:
 724                 retval = joydev_ioctl_common(joydev, cmd, argp);
 725                 break;
 726         }
 727  out:
 728         mutex_unlock(&joydev->mutex);
 729         return retval;
 730 }
 731
 732 static const struct file_operations joydev_fops = {
 733         .owner          = THIS_MODULE,
 734         .read           = joydev_read,
 735         .poll           = joydev_poll,
 736         .open           = joydev_open,
 737         .release        = joydev_release,
 738         .unlocked_ioctl = joydev_ioctl,
 739 #ifdef CONFIG_COMPAT
 740         .compat_ioctl   = joydev_compat_ioctl,
 741 #endif
 742         .fasync         = joydev_fasync,
 743         .llseek         = no_llseek,
 744 };
 745
 746 static int joydev_install_chrdev(struct joydev *joydev)
 747 {
 748         joydev_table[joydev->minor] = joydev;
 749         return 0;
 750 }
 751
 752 static void joydev_remove_chrdev(struct joydev *joydev)
 753 {
 754         mutex_lock(&joydev_table_mutex);
 755         joydev_table[joydev->minor] = NULL;
 756         mutex_unlock(&joydev_table_mutex);
 757 }
 758
 759 /*
 760  * Mark device non-existent. This disables writes, ioctls and
 761  * prevents new users from opening the device. Already posted
 762  * blocking reads will stay, however new ones will fail.
 763  */
 764 static void joydev_mark_dead(struct joydev *joydev)
 765 {
 766         mutex_lock(&joydev->mutex);
 767         joydev->exist = false;
 768         mutex_unlock(&joydev->mutex);
 769 }
 770
 771 static void joydev_cleanup(struct joydev *joydev)
 772 {
 773         struct input_handle *handle = &joydev->handle;
 774
 775         joydev_mark_dead(joydev);
 776         joydev_hangup(joydev);
 777         joydev_remove_chrdev(joydev);
 778
 779         /* joydev is marked dead so no one else accesses joydev->open */
 780         if (joydev->open)
 781                 input_close_device(handle);
 782 }
 783
 784
 785 static bool joydev_match(struct input_handler *handler, struct input_dev *dev)
 786 {
 787         /* Avoid touchpads and touchscreens */
 788         if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_TOUCH, dev->keybit))
 789                 return false;
 790
 791         /* Avoid tablets, digitisers and similar devices */
 792         if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_DIGI, dev->keybit))
 793                 return false;
 794
 795         return true;
 796 }
 797
 798 static int joydev_connect(struct input_handler *handler, struct input_dev *dev,
 799                           const struct input_device_id *id)
 800 {
 801         struct joydev *joydev;
 802         int i, j, t, minor;
 803         int error;
 804
 805         for (minor = 0; minor < JOYDEV_MINORS; minor++)
 806                 if (!joydev_table[minor])
 807                         break;
 808
 809         if (minor == JOYDEV_MINORS) {
 810                 pr_err("no more free joydev devices\n");
 811                 return -ENFILE;
 812         }
 813
 814         joydev = kzalloc(sizeof(struct joydev), GFP_KERNEL);
 815         if (!joydev)
 816                 return -ENOMEM;
 817
 818         INIT_LIST_HEAD(&joydev->client_list);
 819         spin_lock_init(&joydev->client_lock);
 820         mutex_init(&joydev->mutex);
 821         init_waitqueue_head(&joydev->wait);
 822
 823         dev_set_name(&joydev->dev, "js%d", minor);
 824         joydev->exist = true;
 825         joydev->minor = minor;
 826
 827         joydev->handle.dev = input_get_device(dev);
 828         joydev->handle.name = dev_name(&joydev->dev);
 829         joydev->handle.handler = handler;
 830         joydev->handle.private = joydev;
 831
 832         for (i = 0; i < ABS_CNT; i++)
 833                 if (test_bit(i, dev->absbit)) {
 834                         joydev->absmap[i] = joydev->nabs;
 835                         joydev->abspam[joydev->nabs] = i;
 836                         joydev->nabs++;
 837                 }
 838
 839         for (i = BTN_JOYSTICK - BTN_MISC; i < KEY_MAX - BTN_MISC + 1; i++)
 840                 if (test_bit(i + BTN_MISC, dev->keybit)) {
 841                         joydev->keymap[i] = joydev->nkey;
 842                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
 843                         joydev->nkey++;
 844                 }
 845
 846         for (i = 0; i < BTN_JOYSTICK - BTN_MISC; i++)
 847                 if (test_bit(i + BTN_MISC, dev->keybit)) {
 848                         joydev->keymap[i] = joydev->nkey;
 849                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
 850                         joydev->nkey++;
 851                 }
 852
 853         for (i = 0; i < joydev->nabs; i++) {
 854                 j = joydev->abspam[i];
 855                 if (input_abs_get_max(dev, j) == input_abs_get_min(dev, j)) {
 856                         joydev->corr[i].type = JS_CORR_NONE;
 857                         joydev->abs[i] = input_abs_get_val(dev, j);
 858                         continue;
 859                 }
 860                 joydev->corr[i].type = JS_CORR_BROKEN;
 861                 joydev->corr[i].prec = input_abs_get_fuzz(dev, j);
 862
 863                 t = (input_abs_get_max(dev, j) + input_abs_get_min(dev, j)) / 2;
 864                 joydev->corr[i].coef[0] = t - input_abs_get_flat(dev, j);
 865                 joydev->corr[i].coef[1] = t + input_abs_get_flat(dev, j);
 866
 867                 t = (input_abs_get_max(dev, j) - input_abs_get_min(dev, j)) / 2
 868                         - 2 * input_abs_get_flat(dev, j);
 869                 if (t) {
 870                         joydev->corr[i].coef[2] = (1 << 29) / t;
 871                         joydev->corr[i].coef[3] = (1 << 29) / t;
 872
 873                         joydev->abs[i] =
 874                                 joydev_correct(input_abs_get_val(dev, j),
 875                                                joydev->corr + i);
 876                 }
 877         }
 878
 879         joydev->dev.devt = MKDEV(INPUT_MAJOR, JOYDEV_MINOR_BASE + minor);
 880         joydev->dev.class = &input_class;
 881         joydev->dev.parent = &dev->dev;
 882         joydev->dev.release = joydev_free;
 883         device_initialize(&joydev->dev);
 884
 885         error = input_register_handle(&joydev->handle);
 886         if (error)
 887                 goto err_free_joydev;
 888
 889         error = joydev_install_chrdev(joydev);
 890         if (error)
 891                 goto err_unregister_handle;
 892
 893         error = device_add(&joydev->dev);
 894         if (error)
 895                 goto err_cleanup_joydev;
 896
 897         return 0;
 898
 899  err_cleanup_joydev:
 900         joydev_cleanup(joydev);
 901  err_unregister_handle:
 902         input_unregister_handle(&joydev->handle);
 903  err_free_joydev:
 904         put_device(&joydev->dev);
 905         return error;
 906 }
 907
 908 static void joydev_disconnect(struct input_handle *handle)
 909 {
 910         struct joydev *joydev = handle->private;
 911
 912         device_del(&joydev->dev);
 913         joydev_cleanup(joydev);
 914         input_unregister_handle(handle);
 915         put_device(&joydev->dev);
 916 }
 917
 918 static const struct input_device_id joydev_ids[] = {
 919         {
 920                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 921                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 922                 .evbit = { BIT_MASK(EV_ABS) },
 923                 .absbit = { BIT_MASK(ABS_X) },
 924         },
 925         {
 926                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 927                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 928                 .evbit = { BIT_MASK(EV_ABS) },
 929                 .absbit = { BIT_MASK(ABS_WHEEL) },
 930         },
 931         {
 932                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 933                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 934                 .evbit = { BIT_MASK(EV_ABS) },
 935                 .absbit = { BIT_MASK(ABS_THROTTLE) },
 936         },
 937         {
 938                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 939                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
 940                 .evbit = { BIT_MASK(EV_KEY) },
 941                 .keybit = {[BIT_WORD(BTN_JOYSTICK)] = BIT_MASK(BTN_JOYSTICK) },
 942         },
 943         {
 944                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 945                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
 946                 .evbit = { BIT_MASK(EV_KEY) },
 947                 .keybit = { [BIT_WORD(BTN_GAMEPAD)] = BIT_MASK(BTN_GAMEPAD) },
 948         },
 949         {
 950                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 951                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
 952                 .evbit = { BIT_MASK(EV_KEY) },
 953                 .keybit = { [BIT_WORD(BTN_TRIGGER_HAPPY)] = BIT_MASK(BTN_TRIGGER_HAPPY) },
 954         },
 955         { }     /* Terminating entry */
 956 };
 957
 958 MODULE_DEVICE_TABLE(input, joydev_ids);
 959
 960 static struct input_handler joydev_handler = {
 961         .event          = joydev_event,
 962         .match          = joydev_match,
 963         .connect        = joydev_connect,
 964         .disconnect     = joydev_disconnect,
 965         .fops           = &joydev_fops,
 966         .minor          = JOYDEV_MINOR_BASE,
 967         .name           = "joydev",
 968         .id_table       = joydev_ids,
 969 };
 970
 971 static int __init joydev_init(void)
 972 {
 973         return input_register_handler(&joydev_handler);
 974 }
 975
 976 static void __exit joydev_exit(void)
 977 {
 978         input_unregister_handler(&joydev_handler);
 979 }
 980
 981 module_init(joydev_init);
 982 module_exit(joydev_exit);