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 #include <linux/cdev.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         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         struct cdev cdev;
  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 int joydev_correct(int value, struct js_corr *corr)
  75 {
  76         switch (corr->type) {
  77
  78         case JS_CORR_NONE:
  79                 break;
  80
  81         case JS_CORR_BROKEN:
  82                 value = value > corr->coef[0] ? (value < corr->coef[1] ? 0 :
  83                         ((corr->coef[3] * (value - corr->coef[1])) >> 14)) :
  84                         ((corr->coef[2] * (value - corr->coef[0])) >> 14);
  85                 break;
  86
  87         default:
  88                 return 0;
  89         }
  90
  91         return value < -32767 ? -32767 : (value > 32767 ? 32767 : value);
  92 }
  93
  94 static void joydev_pass_event(struct joydev_client *client,
  95                               struct js_event *event)
  96 {
  97         struct joydev *joydev = client->joydev;
  98
  99         /*
 100          * IRQs already disabled, just acquire the lock
 101          */
 102         spin_lock(&client->buffer_lock);
 103
 104         client->buffer[client->head] = *event;
 105
 106         if (client->startup == joydev->nabs + joydev->nkey) {
 107                 client->head++;
 108                 client->head &= JOYDEV_BUFFER_SIZE - 1;
 109                 if (client->tail == client->head)
 110                         client->startup = 0;
 111         }
 112
 113         spin_unlock(&client->buffer_lock);
 114
 115         kill_fasync(&client->fasync, SIGIO, POLL_IN);
 116 }
 117
 118 static void joydev_event(struct input_handle *handle,
 119                          unsigned int type, unsigned int code, int value)
 120 {
 121         struct joydev *joydev = handle->private;
 122         struct joydev_client *client;
 123         struct js_event event;
 124
 125         switch (type) {
 126
 127         case EV_KEY:
 128                 if (code < BTN_MISC || value == 2)
 129                         return;
 130                 event.type = JS_EVENT_BUTTON;
 131                 event.number = joydev->keymap[code - BTN_MISC];
 132                 event.value = value;
 133                 break;
 134
 135         case EV_ABS:
 136                 event.type = JS_EVENT_AXIS;
 137                 event.number = joydev->absmap[code];
 138                 event.value = joydev_correct(value,
 139                                         &joydev->corr[event.number]);
 140                 if (event.value == joydev->abs[event.number])
 141                         return;
 142                 joydev->abs[event.number] = event.value;
 143                 break;
 144
 145         default:
 146                 return;
 147         }
 148
 149         event.time = jiffies_to_msecs(jiffies);
 150
 151         rcu_read_lock();
 152         list_for_each_entry_rcu(client, &joydev->client_list, node)
 153                 joydev_pass_event(client, &event);
 154         rcu_read_unlock();
 155
 156         wake_up_interruptible(&joydev->wait);
 157 }
 158
 159 static int joydev_fasync(int fd, struct file *file, int on)
 160 {
 161         struct joydev_client *client = file->private_data;
 162
 163         return fasync_helper(fd, file, on, &client->fasync);
 164 }
 165
 166 static void joydev_free(struct device *dev)
 167 {
 168         struct joydev *joydev = container_of(dev, struct joydev, dev);
 169
 170         input_put_device(joydev->handle.dev);
 171         kfree(joydev);
 172 }
 173
 174 static void joydev_attach_client(struct joydev *joydev,
 175                                  struct joydev_client *client)
 176 {
 177         spin_lock(&joydev->client_lock);
 178         list_add_tail_rcu(&client->node, &joydev->client_list);
 179         spin_unlock(&joydev->client_lock);
 180 }
 181
 182 static void joydev_detach_client(struct joydev *joydev,
 183                                  struct joydev_client *client)
 184 {
 185         spin_lock(&joydev->client_lock);
 186         list_del_rcu(&client->node);
 187         spin_unlock(&joydev->client_lock);
 188         synchronize_rcu();
 189 }
 190
 191 static int joydev_open_device(struct joydev *joydev)
 192 {
 193         int retval;
 194
 195         retval = mutex_lock_interruptible(&joydev->mutex);
 196         if (retval)
 197                 return retval;
 198
 199         if (!joydev->exist)
 200                 retval = -ENODEV;
 201         else if (!joydev->open++) {
 202                 retval = input_open_device(&joydev->handle);
 203                 if (retval)
 204                         joydev->open--;
 205         }
 206
 207         mutex_unlock(&joydev->mutex);
 208         return retval;
 209 }
 210
 211 static void joydev_close_device(struct joydev *joydev)
 212 {
 213         mutex_lock(&joydev->mutex);
 214
 215         if (joydev->exist && !--joydev->open)
 216                 input_close_device(&joydev->handle);
 217
 218         mutex_unlock(&joydev->mutex);
 219 }
 220
 221 /*
 222  * Wake up users waiting for IO so they can disconnect from
 223  * dead device.
 224  */
 225 static void joydev_hangup(struct joydev *joydev)
 226 {
 227         struct joydev_client *client;
 228
 229         spin_lock(&joydev->client_lock);
 230         list_for_each_entry(client, &joydev->client_list, node)
 231                 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
 232         spin_unlock(&joydev->client_lock);
 233
 234         wake_up_interruptible(&joydev->wait);
 235 }
 236
 237 static int joydev_release(struct inode *inode, struct file *file)
 238 {
 239         struct joydev_client *client = file->private_data;
 240         struct joydev *joydev = client->joydev;
 241
 242         joydev_detach_client(joydev, client);
 243         kfree(client);
 244
 245         joydev_close_device(joydev);
 246
 247         return 0;
 248 }
 249
 250 static int joydev_open(struct inode *inode, struct file *file)
 251 {
 252         struct joydev *joydev =
 253                         container_of(inode->i_cdev, struct joydev, cdev);
 254         struct joydev_client *client;
 255         int error;
 256
 257         client = kzalloc(sizeof(struct joydev_client), GFP_KERNEL);
 258         if (!client)
 259                 return -ENOMEM;
 260
 261         spin_lock_init(&client->buffer_lock);
 262         client->joydev = joydev;
 263         joydev_attach_client(joydev, client);
 264
 265         error = joydev_open_device(joydev);
 266         if (error)
 267                 goto err_free_client;
 268
 269         file->private_data = client;
 270         nonseekable_open(inode, file);
 271
 272         return 0;
 273
 274  err_free_client:
 275         joydev_detach_client(joydev, client);
 276         kfree(client);
 277         return error;
 278 }
 279
 280 static int joydev_generate_startup_event(struct joydev_client *client,
 281                                          struct input_dev *input,
 282                                          struct js_event *event)
 283 {
 284         struct joydev *joydev = client->joydev;
 285         int have_event;
 286
 287         spin_lock_irq(&client->buffer_lock);
 288
 289         have_event = client->startup < joydev->nabs + joydev->nkey;
 290
 291         if (have_event) {
 292
 293                 event->time = jiffies_to_msecs(jiffies);
 294                 if (client->startup < joydev->nkey) {
 295                         event->type = JS_EVENT_BUTTON | JS_EVENT_INIT;
 296                         event->number = client->startup;
 297                         event->value = !!test_bit(joydev->keypam[event->number],
 298                                                   input->key);
 299                 } else {
 300                         event->type = JS_EVENT_AXIS | JS_EVENT_INIT;
 301                         event->number = client->startup - joydev->nkey;
 302                         event->value = joydev->abs[event->number];
 303                 }
 304                 client->startup++;
 305         }
 306
 307         spin_unlock_irq(&client->buffer_lock);
 308
 309         return have_event;
 310 }
 311
 312 static int joydev_fetch_next_event(struct joydev_client *client,
 313                                    struct js_event *event)
 314 {
 315         int have_event;
 316
 317         spin_lock_irq(&client->buffer_lock);
 318
 319         have_event = client->head != client->tail;
 320         if (have_event) {
 321                 *event = client->buffer[client->tail++];
 322                 client->tail &= JOYDEV_BUFFER_SIZE - 1;
 323         }
 324
 325         spin_unlock_irq(&client->buffer_lock);
 326
 327         return have_event;
 328 }
 329
 330 /*
 331  * Old joystick interface
 332  */
 333 static ssize_t joydev_0x_read(struct joydev_client *client,
 334                               struct input_dev *input,
 335                               char __user *buf)
 336 {
 337         struct joydev *joydev = client->joydev;
 338         struct JS_DATA_TYPE data;
 339         int i;
 340
 341         spin_lock_irq(&input->event_lock);
 342
 343         /*
 344          * Get device state
 345          */
 346         for (data.buttons = i = 0; i < 32 && i < joydev->nkey; i++)
 347                 data.buttons |=
 348                         test_bit(joydev->keypam[i], input->key) ? (1 << i) : 0;
 349         data.x = (joydev->abs[0] / 256 + 128) >> joydev->glue.JS_CORR.x;
 350         data.y = (joydev->abs[1] / 256 + 128) >> joydev->glue.JS_CORR.y;
 351
 352         /*
 353          * Reset reader's event queue
 354          */
 355         spin_lock(&client->buffer_lock);
 356         client->startup = 0;
 357         client->tail = client->head;
 358         spin_unlock(&client->buffer_lock);
 359
 360         spin_unlock_irq(&input->event_lock);
 361
 362         if (copy_to_user(buf, &data, sizeof(struct JS_DATA_TYPE)))
 363                 return -EFAULT;
 364
 365         return sizeof(struct JS_DATA_TYPE);
 366 }
 367
 368 static inline int joydev_data_pending(struct joydev_client *client)
 369 {
 370         struct joydev *joydev = client->joydev;
 371
 372         return client->startup < joydev->nabs + joydev->nkey ||
 373                 client->head != client->tail;
 374 }
 375
 376 static ssize_t joydev_read(struct file *file, char __user *buf,
 377                            size_t count, loff_t *ppos)
 378 {
 379         struct joydev_client *client = file->private_data;
 380         struct joydev *joydev = client->joydev;
 381         struct input_dev *input = joydev->handle.dev;
 382         struct js_event event;
 383         int retval;
 384
 385         if (!joydev->exist)
 386                 return -ENODEV;
 387
 388         if (count < sizeof(struct js_event))
 389                 return -EINVAL;
 390
 391         if (count == sizeof(struct JS_DATA_TYPE))
 392                 return joydev_0x_read(client, input, buf);
 393
 394         if (!joydev_data_pending(client) && (file->f_flags & O_NONBLOCK))
 395                 return -EAGAIN;
 396
 397         retval = wait_event_interruptible(joydev->wait,
 398                         !joydev->exist || joydev_data_pending(client));
 399         if (retval)
 400                 return retval;
 401
 402         if (!joydev->exist)
 403                 return -ENODEV;
 404
 405         while (retval + sizeof(struct js_event) <= count &&
 406                joydev_generate_startup_event(client, input, &event)) {
 407
 408                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
 409                         return -EFAULT;
 410
 411                 retval += sizeof(struct js_event);
 412         }
 413
 414         while (retval + sizeof(struct js_event) <= count &&
 415                joydev_fetch_next_event(client, &event)) {
 416
 417                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
 418                         return -EFAULT;
 419
 420                 retval += sizeof(struct js_event);
 421         }
 422
 423         return retval;
 424 }
 425
 426 /* No kernel lock - fine */
 427 static unsigned int joydev_poll(struct file *file, poll_table *wait)
 428 {
 429         struct joydev_client *client = file->private_data;
 430         struct joydev *joydev = client->joydev;
 431
 432         poll_wait(file, &joydev->wait, wait);
 433         return (joydev_data_pending(client) ? (POLLIN | POLLRDNORM) : 0) |
 434                 (joydev->exist ?  0 : (POLLHUP | POLLERR));
 435 }
 436
 437 static int joydev_handle_JSIOCSAXMAP(struct joydev *joydev,
 438                                      void __user *argp, size_t len)
 439 {
 440         __u8 *abspam;
 441         int i;
 442         int retval = 0;
 443
 444         len = min(len, sizeof(joydev->abspam));
 445
 446         /* Validate the map. */
 447         abspam = memdup_user(argp, len);
 448         if (IS_ERR(abspam))
 449                 return PTR_ERR(abspam);
 450
 451         for (i = 0; i < len && i < joydev->nabs; i++) {
 452                 if (abspam[i] > ABS_MAX) {
 453                         retval = -EINVAL;
 454                         goto out;
 455                 }
 456         }
 457
 458         memcpy(joydev->abspam, abspam, len);
 459
 460         for (i = 0; i < joydev->nabs; i++)
 461                 joydev->absmap[joydev->abspam[i]] = i;
 462
 463  out:
 464         kfree(abspam);
 465         return retval;
 466 }
 467
 468 static int joydev_handle_JSIOCSBTNMAP(struct joydev *joydev,
 469                                       void __user *argp, size_t len)
 470 {
 471         __u16 *keypam;
 472         int i;
 473         int retval = 0;
 474
 475         if (len % sizeof(*keypam))
 476                 return -EINVAL;
 477
 478         len = min(len, sizeof(joydev->keypam));
 479
 480         /* Validate the map. */
 481         keypam = memdup_user(argp, len);
 482         if (IS_ERR(keypam))
 483                 return PTR_ERR(keypam);
 484
 485         for (i = 0; i < (len / 2) && i < joydev->nkey; i++) {
 486                 if (keypam[i] > KEY_MAX || keypam[i] < BTN_MISC) {
 487                         retval = -EINVAL;
 488                         goto out;
 489                 }
 490         }
 491
 492         memcpy(joydev->keypam, keypam, len);
 493
 494         for (i = 0; i < joydev->nkey; i++)
 495                 joydev->keymap[joydev->keypam[i] - BTN_MISC] = i;
 496
 497  out:
 498         kfree(keypam);
 499         return retval;
 500 }
 501
 502
 503 static int joydev_ioctl_common(struct joydev *joydev,
 504                                 unsigned int cmd, void __user *argp)
 505 {
 506         struct input_dev *dev = joydev->handle.dev;
 507         size_t len;
 508         int i;
 509         const char *name;
 510
 511         /* Process fixed-sized commands. */
 512         switch (cmd) {
 513
 514         case JS_SET_CAL:
 515                 return copy_from_user(&joydev->glue.JS_CORR, argp,
 516                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
 517
 518         case JS_GET_CAL:
 519                 return copy_to_user(argp, &joydev->glue.JS_CORR,
 520                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
 521
 522         case JS_SET_TIMEOUT:
 523                 return get_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
 524
 525         case JS_GET_TIMEOUT:
 526                 return put_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
 527
 528         case JSIOCGVERSION:
 529                 return put_user(JS_VERSION, (__u32 __user *) argp);
 530
 531         case JSIOCGAXES:
 532                 return put_user(joydev->nabs, (__u8 __user *) argp);
 533
 534         case JSIOCGBUTTONS:
 535                 return put_user(joydev->nkey, (__u8 __user *) argp);
 536
 537         case JSIOCSCORR:
 538                 if (copy_from_user(joydev->corr, argp,
 539                               sizeof(joydev->corr[0]) * joydev->nabs))
 540                         return -EFAULT;
 541
 542                 for (i = 0; i < joydev->nabs; i++) {
 543                         int val = input_abs_get_val(dev, joydev->abspam[i]);
 544                         joydev->abs[i] = joydev_correct(val, &joydev->corr[i]);
 545                 }
 546                 return 0;
 547
 548         case JSIOCGCORR:
 549                 return copy_to_user(argp, joydev->corr,
 550                         sizeof(joydev->corr[0]) * joydev->nabs) ? -EFAULT : 0;
 551
 552         }
 553
 554         /*
 555          * Process variable-sized commands (the axis and button map commands
 556          * are considered variable-sized to decouple them from the values of
 557          * ABS_MAX and KEY_MAX).
 558          */
 559         switch (cmd & ~IOCSIZE_MASK) {
 560
 561         case (JSIOCSAXMAP & ~IOCSIZE_MASK):
 562                 return joydev_handle_JSIOCSAXMAP(joydev, argp, _IOC_SIZE(cmd));
 563
 564         case (JSIOCGAXMAP & ~IOCSIZE_MASK):
 565                 len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->abspam));
 566                 return copy_to_user(argp, joydev->abspam, len) ? -EFAULT : len;
 567
 568         case (JSIOCSBTNMAP & ~IOCSIZE_MASK):
 569                 return joydev_handle_JSIOCSBTNMAP(joydev, argp, _IOC_SIZE(cmd));
 570
 571         case (JSIOCGBTNMAP & ~IOCSIZE_MASK):
 572                 len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->keypam));
 573                 return copy_to_user(argp, joydev->keypam, len) ? -EFAULT : len;
 574
 575         case JSIOCGNAME(0):
 576                 name = dev->name;
 577                 if (!name)
 578                         return 0;
 579
 580                 len = min_t(size_t, _IOC_SIZE(cmd), strlen(name) + 1);
 581                 return copy_to_user(argp, name, len) ? -EFAULT : len;
 582         }
 583
 584         return -EINVAL;
 585 }
 586
 587 #ifdef CONFIG_COMPAT
 588 static long joydev_compat_ioctl(struct file *file,
 589                                 unsigned int cmd, unsigned long arg)
 590 {
 591         struct joydev_client *client = file->private_data;
 592         struct joydev *joydev = client->joydev;
 593         void __user *argp = (void __user *)arg;
 594         s32 tmp32;
 595         struct JS_DATA_SAVE_TYPE_32 ds32;
 596         int retval;
 597
 598         retval = mutex_lock_interruptible(&joydev->mutex);
 599         if (retval)
 600                 return retval;
 601
 602         if (!joydev->exist) {
 603                 retval = -ENODEV;
 604                 goto out;
 605         }
 606
 607         switch (cmd) {
 608
 609         case JS_SET_TIMELIMIT:
 610                 retval = get_user(tmp32, (s32 __user *) arg);
 611                 if (retval == 0)
 612                         joydev->glue.JS_TIMELIMIT = tmp32;
 613                 break;
 614
 615         case JS_GET_TIMELIMIT:
 616                 tmp32 = joydev->glue.JS_TIMELIMIT;
 617                 retval = put_user(tmp32, (s32 __user *) arg);
 618                 break;
 619
 620         case JS_SET_ALL:
 621                 retval = copy_from_user(&ds32, argp,
 622                                         sizeof(ds32)) ? -EFAULT : 0;
 623                 if (retval == 0) {
 624                         joydev->glue.JS_TIMEOUT    = ds32.JS_TIMEOUT;
 625                         joydev->glue.BUSY          = ds32.BUSY;
 626                         joydev->glue.JS_EXPIRETIME = ds32.JS_EXPIRETIME;
 627                         joydev->glue.JS_TIMELIMIT  = ds32.JS_TIMELIMIT;
 628                         joydev->glue.JS_SAVE       = ds32.JS_SAVE;
 629                         joydev->glue.JS_CORR       = ds32.JS_CORR;
 630                 }
 631                 break;
 632
 633         case JS_GET_ALL:
 634                 ds32.JS_TIMEOUT    = joydev->glue.JS_TIMEOUT;
 635                 ds32.BUSY          = joydev->glue.BUSY;
 636                 ds32.JS_EXPIRETIME = joydev->glue.JS_EXPIRETIME;
 637                 ds32.JS_TIMELIMIT  = joydev->glue.JS_TIMELIMIT;
 638                 ds32.JS_SAVE       = joydev->glue.JS_SAVE;
 639                 ds32.JS_CORR       = joydev->glue.JS_CORR;
 640
 641                 retval = copy_to_user(argp, &ds32, sizeof(ds32)) ? -EFAULT : 0;
 642                 break;
 643
 644         default:
 645                 retval = joydev_ioctl_common(joydev, cmd, argp);
 646                 break;
 647         }
 648
 649  out:
 650         mutex_unlock(&joydev->mutex);
 651         return retval;
 652 }
 653 #endif /* CONFIG_COMPAT */
 654
 655 static long joydev_ioctl(struct file *file,
 656                          unsigned int cmd, unsigned long arg)
 657 {
 658         struct joydev_client *client = file->private_data;
 659         struct joydev *joydev = client->joydev;
 660         void __user *argp = (void __user *)arg;
 661         int retval;
 662
 663         retval = mutex_lock_interruptible(&joydev->mutex);
 664         if (retval)
 665                 return retval;
 666
 667         if (!joydev->exist) {
 668                 retval = -ENODEV;
 669                 goto out;
 670         }
 671
 672         switch (cmd) {
 673
 674         case JS_SET_TIMELIMIT:
 675                 retval = get_user(joydev->glue.JS_TIMELIMIT,
 676                                   (long __user *) arg);
 677                 break;
 678
 679         case JS_GET_TIMELIMIT:
 680                 retval = put_user(joydev->glue.JS_TIMELIMIT,
 681                                   (long __user *) arg);
 682                 break;
 683
 684         case JS_SET_ALL:
 685                 retval = copy_from_user(&joydev->glue, argp,
 686                                         sizeof(joydev->glue)) ? -EFAULT : 0;
 687                 break;
 688
 689         case JS_GET_ALL:
 690                 retval = copy_to_user(argp, &joydev->glue,
 691                                       sizeof(joydev->glue)) ? -EFAULT : 0;
 692                 break;
 693
 694         default:
 695                 retval = joydev_ioctl_common(joydev, cmd, argp);
 696                 break;
 697         }
 698  out:
 699         mutex_unlock(&joydev->mutex);
 700         return retval;
 701 }
 702
 703 static const struct file_operations joydev_fops = {
 704         .owner          = THIS_MODULE,
 705         .read           = joydev_read,
 706         .poll           = joydev_poll,
 707         .open           = joydev_open,
 708         .release        = joydev_release,
 709         .unlocked_ioctl = joydev_ioctl,
 710 #ifdef CONFIG_COMPAT
 711         .compat_ioctl   = joydev_compat_ioctl,
 712 #endif
 713         .fasync         = joydev_fasync,
 714         .llseek         = no_llseek,
 715 };
 716
 717 /*
 718  * Mark device non-existent. This disables writes, ioctls and
 719  * prevents new users from opening the device. Already posted
 720  * blocking reads will stay, however new ones will fail.
 721  */
 722 static void joydev_mark_dead(struct joydev *joydev)
 723 {
 724         mutex_lock(&joydev->mutex);
 725         joydev->exist = false;
 726         mutex_unlock(&joydev->mutex);
 727 }
 728
 729 static void joydev_cleanup(struct joydev *joydev)
 730 {
 731         struct input_handle *handle = &joydev->handle;
 732
 733         joydev_mark_dead(joydev);
 734         joydev_hangup(joydev);
 735
 736         cdev_del(&joydev->cdev);
 737
 738         /* joydev is marked dead so no one else accesses joydev->open */
 739         if (joydev->open)
 740                 input_close_device(handle);
 741 }
 742
 743 static bool joydev_dev_is_absolute_mouse(struct input_dev *dev)
 744 {
 745         DECLARE_BITMAP(jd_scratch, KEY_CNT);
 746
 747         BUILD_BUG_ON(ABS_CNT > KEY_CNT || EV_CNT > KEY_CNT);
 748
 749         /*
 750          * Virtualization (VMware, etc) and remote management (HP
 751          * ILO2) solutions use absolute coordinates for their virtual
 752          * pointing devices so that there is one-to-one relationship
 753          * between pointer position on the host screen and virtual
 754          * guest screen, and so their mice use ABS_X, ABS_Y and 3
 755          * primary button events. This clashes with what joydev
 756          * considers to be joysticks (a device with at minimum ABS_X
 757          * axis).
 758          *
 759          * Here we are trying to separate absolute mice from
 760          * joysticks. A device is, for joystick detection purposes,
 761          * considered to be an absolute mouse if the following is
 762          * true:
 763          *
 764          * 1) Event types are exactly EV_ABS, EV_KEY and EV_SYN.
 765          * 2) Absolute events are exactly ABS_X and ABS_Y.
 766          * 3) Keys are exactly BTN_LEFT, BTN_RIGHT and BTN_MIDDLE.
 767          * 4) Device is not on "Amiga" bus.
 768          */
 769
 770         bitmap_zero(jd_scratch, EV_CNT);
 771         __set_bit(EV_ABS, jd_scratch);
 772         __set_bit(EV_KEY, jd_scratch);
 773         __set_bit(EV_SYN, jd_scratch);
 774         if (!bitmap_equal(jd_scratch, dev->evbit, EV_CNT))
 775                 return false;
 776
 777         bitmap_zero(jd_scratch, ABS_CNT);
 778         __set_bit(ABS_X, jd_scratch);
 779         __set_bit(ABS_Y, jd_scratch);
 780         if (!bitmap_equal(dev->absbit, jd_scratch, ABS_CNT))
 781                 return false;
 782
 783         bitmap_zero(jd_scratch, KEY_CNT);
 784         __set_bit(BTN_LEFT, jd_scratch);
 785         __set_bit(BTN_RIGHT, jd_scratch);
 786         __set_bit(BTN_MIDDLE, jd_scratch);
 787
 788         if (!bitmap_equal(dev->keybit, jd_scratch, KEY_CNT))
 789                 return false;
 790
 791         /*
 792          * Amiga joystick (amijoy) historically uses left/middle/right
 793          * button events.
 794          */
 795         if (dev->id.bustype == BUS_AMIGA)
 796                 return false;
 797
 798         return true;
 799 }
 800
 801 static bool joydev_match(struct input_handler *handler, struct input_dev *dev)
 802 {
 803         /* Avoid touchpads and touchscreens */
 804         if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_TOUCH, dev->keybit))
 805                 return false;
 806
 807         /* Avoid tablets, digitisers and similar devices */
 808         if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_DIGI, dev->keybit))
 809                 return false;
 810
 811         /* Avoid absolute mice */
 812         if (joydev_dev_is_absolute_mouse(dev))
 813                 return false;
 814
 815         return true;
 816 }
 817
 818 static int joydev_connect(struct input_handler *handler, struct input_dev *dev,
 819                           const struct input_device_id *id)
 820 {
 821         struct joydev *joydev;
 822         int i, j, t, minor, dev_no;
 823         int error;
 824
 825         minor = input_get_new_minor(JOYDEV_MINOR_BASE, JOYDEV_MINORS, true);
 826         if (minor < 0) {
 827                 error = minor;
 828                 pr_err("failed to reserve new minor: %d\n", error);
 829                 return error;
 830         }
 831
 832         joydev = kzalloc(sizeof(struct joydev), GFP_KERNEL);
 833         if (!joydev) {
 834                 error = -ENOMEM;
 835                 goto err_free_minor;
 836         }
 837
 838         INIT_LIST_HEAD(&joydev->client_list);
 839         spin_lock_init(&joydev->client_lock);
 840         mutex_init(&joydev->mutex);
 841         init_waitqueue_head(&joydev->wait);
 842         joydev->exist = true;
 843
 844         dev_no = minor;
 845         /* Normalize device number if it falls into legacy range */
 846         if (dev_no < JOYDEV_MINOR_BASE + JOYDEV_MINORS)
 847                 dev_no -= JOYDEV_MINOR_BASE;
 848         dev_set_name(&joydev->dev, "js%d", dev_no);
 849
 850         joydev->handle.dev = input_get_device(dev);
 851         joydev->handle.name = dev_name(&joydev->dev);
 852         joydev->handle.handler = handler;
 853         joydev->handle.private = joydev;
 854
 855         for_each_set_bit(i, dev->absbit, ABS_CNT) {
 856                 joydev->absmap[i] = joydev->nabs;
 857                 joydev->abspam[joydev->nabs] = i;
 858                 joydev->nabs++;
 859         }
 860
 861         for (i = BTN_JOYSTICK - BTN_MISC; i < KEY_MAX - BTN_MISC + 1; i++)
 862                 if (test_bit(i + BTN_MISC, dev->keybit)) {
 863                         joydev->keymap[i] = joydev->nkey;
 864                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
 865                         joydev->nkey++;
 866                 }
 867
 868         for (i = 0; i < BTN_JOYSTICK - BTN_MISC; i++)
 869                 if (test_bit(i + BTN_MISC, dev->keybit)) {
 870                         joydev->keymap[i] = joydev->nkey;
 871                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
 872                         joydev->nkey++;
 873                 }
 874
 875         for (i = 0; i < joydev->nabs; i++) {
 876                 j = joydev->abspam[i];
 877                 if (input_abs_get_max(dev, j) == input_abs_get_min(dev, j)) {
 878                         joydev->corr[i].type = JS_CORR_NONE;
 879                         joydev->abs[i] = input_abs_get_val(dev, j);
 880                         continue;
 881                 }
 882                 joydev->corr[i].type = JS_CORR_BROKEN;
 883                 joydev->corr[i].prec = input_abs_get_fuzz(dev, j);
 884
 885                 t = (input_abs_get_max(dev, j) + input_abs_get_min(dev, j)) / 2;
 886                 joydev->corr[i].coef[0] = t - input_abs_get_flat(dev, j);
 887                 joydev->corr[i].coef[1] = t + input_abs_get_flat(dev, j);
 888
 889                 t = (input_abs_get_max(dev, j) - input_abs_get_min(dev, j)) / 2
 890                         - 2 * input_abs_get_flat(dev, j);
 891                 if (t) {
 892                         joydev->corr[i].coef[2] = (1 << 29) / t;
 893                         joydev->corr[i].coef[3] = (1 << 29) / t;
 894
 895                         joydev->abs[i] =
 896                                 joydev_correct(input_abs_get_val(dev, j),
 897                                                joydev->corr + i);
 898                 }
 899         }
 900
 901         joydev->dev.devt = MKDEV(INPUT_MAJOR, minor);
 902         joydev->dev.class = &input_class;
 903         joydev->dev.parent = &dev->dev;
 904         joydev->dev.release = joydev_free;
 905         device_initialize(&joydev->dev);
 906
 907         error = input_register_handle(&joydev->handle);
 908         if (error)
 909                 goto err_free_joydev;
 910
 911         cdev_init(&joydev->cdev, &joydev_fops);
 912         joydev->cdev.kobj.parent = &joydev->dev.kobj;
 913         error = cdev_add(&joydev->cdev, joydev->dev.devt, 1);
 914         if (error)
 915                 goto err_unregister_handle;
 916
 917         error = device_add(&joydev->dev);
 918         if (error)
 919                 goto err_cleanup_joydev;
 920
 921         return 0;
 922
 923  err_cleanup_joydev:
 924         joydev_cleanup(joydev);
 925  err_unregister_handle:
 926         input_unregister_handle(&joydev->handle);
 927  err_free_joydev:
 928         put_device(&joydev->dev);
 929  err_free_minor:
 930         input_free_minor(minor);
 931         return error;
 932 }
 933
 934 static void joydev_disconnect(struct input_handle *handle)
 935 {
 936         struct joydev *joydev = handle->private;
 937
 938         device_del(&joydev->dev);
 939         joydev_cleanup(joydev);
 940         input_free_minor(MINOR(joydev->dev.devt));
 941         input_unregister_handle(handle);
 942         put_device(&joydev->dev);
 943 }
 944
 945 static const struct input_device_id joydev_ids[] = {
 946         {
 947                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 948                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 949                 .evbit = { BIT_MASK(EV_ABS) },
 950                 .absbit = { BIT_MASK(ABS_X) },
 951         },
 952         {
 953                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 954                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 955                 .evbit = { BIT_MASK(EV_ABS) },
 956                 .absbit = { BIT_MASK(ABS_Z) },
 957         },
 958         {
 959                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 960                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 961                 .evbit = { BIT_MASK(EV_ABS) },
 962                 .absbit = { BIT_MASK(ABS_WHEEL) },
 963         },
 964         {
 965                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 966                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
 967                 .evbit = { BIT_MASK(EV_ABS) },
 968                 .absbit = { BIT_MASK(ABS_THROTTLE) },
 969         },
 970         {
 971                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 972                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
 973                 .evbit = { BIT_MASK(EV_KEY) },
 974                 .keybit = {[BIT_WORD(BTN_JOYSTICK)] = BIT_MASK(BTN_JOYSTICK) },
 975         },
 976         {
 977                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 978                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
 979                 .evbit = { BIT_MASK(EV_KEY) },
 980                 .keybit = { [BIT_WORD(BTN_GAMEPAD)] = BIT_MASK(BTN_GAMEPAD) },
 981         },
 982         {
 983                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 984                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
 985                 .evbit = { BIT_MASK(EV_KEY) },
 986                 .keybit = { [BIT_WORD(BTN_TRIGGER_HAPPY)] = BIT_MASK(BTN_TRIGGER_HAPPY) },
 987         },
 988         { }     /* Terminating entry */
 989 };
 990
 991 MODULE_DEVICE_TABLE(input, joydev_ids);
 992
 993 static struct input_handler joydev_handler = {
 994         .event          = joydev_event,
 995         .match          = joydev_match,
 996         .connect        = joydev_connect,
 997         .disconnect     = joydev_disconnect,
 998         .legacy_minors  = true,
 999         .minor          = JOYDEV_MINOR_BASE,
1000         .name           = "joydev",
1001         .id_table       = joydev_ids,
1002 };
1003
1004 static int __init joydev_init(void)
1005 {
1006         return input_register_handler(&joydev_handler);
1007 }
1008
1009 static void __exit joydev_exit(void)
1010 {
1011         input_unregister_handler(&joydev_handler);
1012 }
1013
1014 module_init(joydev_init);
1015 module_exit(joydev_exit);