drivers/input/joydev.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Joystick device driver for the input driver suite.
   4  *
   5  * Copyright (c) 1999-2002 Vojtech Pavlik
   6  * Copyright (c) 1999 Colin Van Dyke
   7  */
   8
   9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  10
  11 #include <asm/io.h>
  12 #include <linux/delay.h>
  13 #include <linux/errno.h>
  14 #include <linux/joystick.h>
  15 #include <linux/input.h>
  16 #include <linux/kernel.h>
  17 #include <linux/major.h>
  18 #include <linux/sched.h>
  19 #include <linux/slab.h>
  20 #include <linux/mm.h>
  21 #include <linux/module.h>
  22 #include <linux/poll.h>
  23 #include <linux/init.h>
  24 #include <linux/device.h>
  25 #include <linux/cdev.h>
  26
  27 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
  28 MODULE_DESCRIPTION("Joystick device interfaces");
  29 MODULE_SUPPORTED_DEVICE("input/js");
  30 MODULE_LICENSE("GPL");
  31
  32 #define JOYDEV_MINOR_BASE       0
  33 #define JOYDEV_MINORS           16
  34 #define JOYDEV_BUFFER_SIZE      64
  35
  36 struct joydev {
  37         int open;
  38         struct input_handle handle;
  39         wait_queue_head_t wait;
  40         struct list_head client_list;
  41         spinlock_t client_lock; /* protects client_list */
  42         struct mutex mutex;
  43         struct device dev;
  44         struct cdev cdev;
  45         bool exist;
  46
  47         struct js_corr corr[ABS_CNT];
  48         struct JS_DATA_SAVE_TYPE glue;
  49         int nabs;
  50         int nkey;
  51         __u16 keymap[KEY_MAX - BTN_MISC + 1];
  52         __u16 keypam[KEY_MAX - BTN_MISC + 1];
  53         __u8 absmap[ABS_CNT];
  54         __u8 abspam[ABS_CNT];
  55         __s16 abs[ABS_CNT];
  56 };
  57
  58 struct joydev_client {
  59         struct js_event buffer[JOYDEV_BUFFER_SIZE];
  60         int head;
  61         int tail;
  62         int startup;
  63         spinlock_t buffer_lock; /* protects access to buffer, head and tail */
  64         struct fasync_struct *fasync;
  65         struct joydev *joydev;
  66         struct list_head node;
  67 };
  68
  69 static int joydev_correct(int value, struct js_corr *corr)
  70 {
  71         switch (corr->type) {
  72
  73         case JS_CORR_NONE:
  74                 break;
  75
  76         case JS_CORR_BROKEN:
  77                 value = value > corr->coef[0] ? (value < corr->coef[1] ? 0 :
  78                         ((corr->coef[3] * (value - corr->coef[1])) >> 14)) :
  79                         ((corr->coef[2] * (value - corr->coef[0])) >> 14);
  80                 break;
  81
  82         default:
  83                 return 0;
  84         }
  85
  86         return clamp(value, -32767, 32767);
  87 }
  88
  89 static void joydev_pass_event(struct joydev_client *client,
  90                               struct js_event *event)
  91 {
  92         struct joydev *joydev = client->joydev;
  93
  94         /*
  95          * IRQs already disabled, just acquire the lock
  96          */
  97         spin_lock(&client->buffer_lock);
  98
  99         client->buffer[client->head] = *event;
 100
 101         if (client->startup == joydev->nabs + joydev->nkey) {
 102                 client->head++;
 103                 client->head &= JOYDEV_BUFFER_SIZE - 1;
 104                 if (client->tail == client->head)
 105                         client->startup = 0;
 106         }
 107
 108         spin_unlock(&client->buffer_lock);
 109
 110         kill_fasync(&client->fasync, SIGIO, POLL_IN);
 111 }
 112
 113 static void joydev_event(struct input_handle *handle,
 114                          unsigned int type, unsigned int code, int value)
 115 {
 116         struct joydev *joydev = handle->private;
 117         struct joydev_client *client;
 118         struct js_event event;
 119
 120         switch (type) {
 121
 122         case EV_KEY:
 123                 if (code < BTN_MISC || value == 2)
 124                         return;
 125                 event.type = JS_EVENT_BUTTON;
 126                 event.number = joydev->keymap[code - BTN_MISC];
 127                 event.value = value;
 128                 break;
 129
 130         case EV_ABS:
 131                 event.type = JS_EVENT_AXIS;
 132                 event.number = joydev->absmap[code];
 133                 event.value = joydev_correct(value,
 134                                         &joydev->corr[event.number]);
 135                 if (event.value == joydev->abs[event.number])
 136                         return;
 137                 joydev->abs[event.number] = event.value;
 138                 break;
 139
 140         default:
 141                 return;
 142         }
 143
 144         event.time = jiffies_to_msecs(jiffies);
 145
 146         rcu_read_lock();
 147         list_for_each_entry_rcu(client, &joydev->client_list, node)
 148                 joydev_pass_event(client, &event);
 149         rcu_read_unlock();
 150
 151         wake_up_interruptible(&joydev->wait);
 152 }
 153
 154 static int joydev_fasync(int fd, struct file *file, int on)
 155 {
 156         struct joydev_client *client = file->private_data;
 157
 158         return fasync_helper(fd, file, on, &client->fasync);
 159 }
 160
 161 static void joydev_free(struct device *dev)
 162 {
 163         struct joydev *joydev = container_of(dev, struct joydev, dev);
 164
 165         input_put_device(joydev->handle.dev);
 166         kfree(joydev);
 167 }
 168
 169 static void joydev_attach_client(struct joydev *joydev,
 170                                  struct joydev_client *client)
 171 {
 172         spin_lock(&joydev->client_lock);
 173         list_add_tail_rcu(&client->node, &joydev->client_list);
 174         spin_unlock(&joydev->client_lock);
 175 }
 176
 177 static void joydev_detach_client(struct joydev *joydev,
 178                                  struct joydev_client *client)
 179 {
 180         spin_lock(&joydev->client_lock);
 181         list_del_rcu(&client->node);
 182         spin_unlock(&joydev->client_lock);
 183         synchronize_rcu();
 184 }
 185
 186 static void joydev_refresh_state(struct joydev *joydev)
 187 {
 188         struct input_dev *dev = joydev->handle.dev;
 189         int i, val;
 190
 191         for (i = 0; i < joydev->nabs; i++) {
 192                 val = input_abs_get_val(dev, joydev->abspam[i]);
 193                 joydev->abs[i] = joydev_correct(val, &joydev->corr[i]);
 194         }
 195 }
 196
 197 static int joydev_open_device(struct joydev *joydev)
 198 {
 199         int retval;
 200
 201         retval = mutex_lock_interruptible(&joydev->mutex);
 202         if (retval)
 203                 return retval;
 204
 205         if (!joydev->exist)
 206                 retval = -ENODEV;
 207         else if (!joydev->open++) {
 208                 retval = input_open_device(&joydev->handle);
 209                 if (retval)
 210                         joydev->open--;
 211                 else
 212                         joydev_refresh_state(joydev);
 213         }
 214
 215         mutex_unlock(&joydev->mutex);
 216         return retval;
 217 }
 218
 219 static void joydev_close_device(struct joydev *joydev)
 220 {
 221         mutex_lock(&joydev->mutex);
 222
 223         if (joydev->exist && !--joydev->open)
 224                 input_close_device(&joydev->handle);
 225
 226         mutex_unlock(&joydev->mutex);
 227 }
 228
 229 /*
 230  * Wake up users waiting for IO so they can disconnect from
 231  * dead device.
 232  */
 233 static void joydev_hangup(struct joydev *joydev)
 234 {
 235         struct joydev_client *client;
 236
 237         spin_lock(&joydev->client_lock);
 238         list_for_each_entry(client, &joydev->client_list, node)
 239                 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
 240         spin_unlock(&joydev->client_lock);
 241
 242         wake_up_interruptible(&joydev->wait);
 243 }
 244
 245 static int joydev_release(struct inode *inode, struct file *file)
 246 {
 247         struct joydev_client *client = file->private_data;
 248         struct joydev *joydev = client->joydev;
 249
 250         joydev_detach_client(joydev, client);
 251         kfree(client);
 252
 253         joydev_close_device(joydev);
 254
 255         return 0;
 256 }
 257
 258 static int joydev_open(struct inode *inode, struct file *file)
 259 {
 260         struct joydev *joydev =
 261                         container_of(inode->i_cdev, struct joydev, cdev);
 262         struct joydev_client *client;
 263         int error;
 264
 265         client = kzalloc(sizeof(struct joydev_client), GFP_KERNEL);
 266         if (!client)
 267                 return -ENOMEM;
 268
 269         spin_lock_init(&client->buffer_lock);
 270         client->joydev = joydev;
 271         joydev_attach_client(joydev, client);
 272
 273         error = joydev_open_device(joydev);
 274         if (error)
 275                 goto err_free_client;
 276
 277         file->private_data = client;
 278         stream_open(inode, file);
 279
 280         return 0;
 281
 282  err_free_client:
 283         joydev_detach_client(joydev, client);
 284         kfree(client);
 285         return error;
 286 }
 287
 288 static int joydev_generate_startup_event(struct joydev_client *client,
 289                                          struct input_dev *input,
 290                                          struct js_event *event)
 291 {
 292         struct joydev *joydev = client->joydev;
 293         int have_event;
 294
 295         spin_lock_irq(&client->buffer_lock);
 296
 297         have_event = client->startup < joydev->nabs + joydev->nkey;
 298
 299         if (have_event) {
 300
 301                 event->time = jiffies_to_msecs(jiffies);
 302                 if (client->startup < joydev->nkey) {
 303                         event->type = JS_EVENT_BUTTON | JS_EVENT_INIT;
 304                         event->number = client->startup;
 305                         event->value = !!test_bit(joydev->keypam[event->number],
 306                                                   input->key);
 307                 } else {
 308                         event->type = JS_EVENT_AXIS | JS_EVENT_INIT;
 309                         event->number = client->startup - joydev->nkey;
 310                         event->value = joydev->abs[event->number];
 311                 }
 312                 client->startup++;
 313         }
 314
 315         spin_unlock_irq(&client->buffer_lock);
 316
 317         return have_event;
 318 }
 319
 320 static int joydev_fetch_next_event(struct joydev_client *client,
 321                                    struct js_event *event)
 322 {
 323         int have_event;
 324
 325         spin_lock_irq(&client->buffer_lock);
 326
 327         have_event = client->head != client->tail;
 328         if (have_event) {
 329                 *event = client->buffer[client->tail++];
 330                 client->tail &= JOYDEV_BUFFER_SIZE - 1;
 331         }
 332
 333         spin_unlock_irq(&client->buffer_lock);
 334
 335         return have_event;
 336 }
 337
 338 /*
 339  * Old joystick interface
 340  */
 341 static ssize_t joydev_0x_read(struct joydev_client *client,
 342                               struct input_dev *input,
 343                               char __user *buf)
 344 {
 345         struct joydev *joydev = client->joydev;
 346         struct JS_DATA_TYPE data;
 347         int i;
 348
 349         spin_lock_irq(&input->event_lock);
 350
 351         /*
 352          * Get device state
 353          */
 354         for (data.buttons = i = 0; i < 32 && i < joydev->nkey; i++)
 355                 data.buttons |=
 356                         test_bit(joydev->keypam[i], input->key) ? (1 << i) : 0;
 357         data.x = (joydev->abs[0] / 256 + 128) >> joydev->glue.JS_CORR.x;
 358         data.y = (joydev->abs[1] / 256 + 128) >> joydev->glue.JS_CORR.y;
 359
 360         /*
 361          * Reset reader's event queue
 362          */
 363         spin_lock(&client->buffer_lock);
 364         client->startup = 0;
 365         client->tail = client->head;
 366         spin_unlock(&client->buffer_lock);
 367
 368         spin_unlock_irq(&input->event_lock);
 369
 370         if (copy_to_user(buf, &data, sizeof(struct JS_DATA_TYPE)))
 371                 return -EFAULT;
 372
 373         return sizeof(struct JS_DATA_TYPE);
 374 }
 375
 376 static inline int joydev_data_pending(struct joydev_client *client)
 377 {
 378         struct joydev *joydev = client->joydev;
 379
 380         return client->startup < joydev->nabs + joydev->nkey ||
 381                 client->head != client->tail;
 382 }
 383
 384 static ssize_t joydev_read(struct file *file, char __user *buf,
 385                            size_t count, loff_t *ppos)
 386 {
 387         struct joydev_client *client = file->private_data;
 388         struct joydev *joydev = client->joydev;
 389         struct input_dev *input = joydev->handle.dev;
 390         struct js_event event;
 391         int retval;
 392
 393         if (!joydev->exist)
 394                 return -ENODEV;
 395
 396         if (count < sizeof(struct js_event))
 397                 return -EINVAL;
 398
 399         if (count == sizeof(struct JS_DATA_TYPE))
 400                 return joydev_0x_read(client, input, buf);
 401
 402         if (!joydev_data_pending(client) && (file->f_flags & O_NONBLOCK))
 403                 return -EAGAIN;
 404
 405         retval = wait_event_interruptible(joydev->wait,
 406                         !joydev->exist || joydev_data_pending(client));
 407         if (retval)
 408                 return retval;
 409
 410         if (!joydev->exist)
 411                 return -ENODEV;
 412
 413         while (retval + sizeof(struct js_event) <= count &&
 414                joydev_generate_startup_event(client, input, &event)) {
 415
 416                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
 417                         return -EFAULT;
 418
 419                 retval += sizeof(struct js_event);
 420         }
 421
 422         while (retval + sizeof(struct js_event) <= count &&
 423                joydev_fetch_next_event(client, &event)) {
 424
 425                 if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
 426                         return -EFAULT;
 427
 428                 retval += sizeof(struct js_event);
 429         }
 430
 431         return retval;
 432 }
 433
 434 /* No kernel lock - fine */
 435 static __poll_t joydev_poll(struct file *file, poll_table *wait)
 436 {
 437         struct joydev_client *client = file->private_data;
 438         struct joydev *joydev = client->joydev;
 439
 440         poll_wait(file, &joydev->wait, wait);
 441         return (joydev_data_pending(client) ? (EPOLLIN | EPOLLRDNORM) : 0) |
 442                 (joydev->exist ?  0 : (EPOLLHUP | EPOLLERR));
 443 }
 444
 445 static int joydev_handle_JSIOCSAXMAP(struct joydev *joydev,
 446                                      void __user *argp, size_t len)
 447 {
 448         __u8 *abspam;
 449         int i;
 450         int retval = 0;
 451
 452         len = min(len, sizeof(joydev->abspam));
 453
 454         /* Validate the map. */
 455         abspam = memdup_user(argp, len);
 456         if (IS_ERR(abspam))
 457                 return PTR_ERR(abspam);
 458
 459         for (i = 0; i < len && i < joydev->nabs; i++) {
 460                 if (abspam[i] > ABS_MAX) {
 461                         retval = -EINVAL;
 462                         goto out;
 463                 }
 464         }
 465
 466         memcpy(joydev->abspam, abspam, len);
 467
 468         for (i = 0; i < joydev->nabs; i++)
 469                 joydev->absmap[joydev->abspam[i]] = i;
 470
 471  out:
 472         kfree(abspam);
 473         return retval;
 474 }
 475
 476 static int joydev_handle_JSIOCSBTNMAP(struct joydev *joydev,
 477                                       void __user *argp, size_t len)
 478 {
 479         __u16 *keypam;
 480         int i;
 481         int retval = 0;
 482
 483         if (len % sizeof(*keypam))
 484                 return -EINVAL;
 485
 486         len = min(len, sizeof(joydev->keypam));
 487
 488         /* Validate the map. */
 489         keypam = memdup_user(argp, len);
 490         if (IS_ERR(keypam))
 491                 return PTR_ERR(keypam);
 492
 493         for (i = 0; i < (len / 2) && i < joydev->nkey; i++) {
 494                 if (keypam[i] > KEY_MAX || keypam[i] < BTN_MISC) {
 495                         retval = -EINVAL;
 496                         goto out;
 497                 }
 498         }
 499
 500         memcpy(joydev->keypam, keypam, len);
 501
 502         for (i = 0; i < joydev->nkey; i++)
 503                 joydev->keymap[keypam[i] - BTN_MISC] = i;
 504
 505  out:
 506         kfree(keypam);
 507         return retval;
 508 }
 509
 510
 511 static int joydev_ioctl_common(struct joydev *joydev,
 512                                 unsigned int cmd, void __user *argp)
 513 {
 514         struct input_dev *dev = joydev->handle.dev;
 515         size_t len;
 516         int i;
 517         const char *name;
 518
 519         /* Process fixed-sized commands. */
 520         switch (cmd) {
 521
 522         case JS_SET_CAL:
 523                 return copy_from_user(&joydev->glue.JS_CORR, argp,
 524                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
 525
 526         case JS_GET_CAL:
 527                 return copy_to_user(argp, &joydev->glue.JS_CORR,
 528                                 sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;
 529
 530         case JS_SET_TIMEOUT:
 531                 return get_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
 532
 533         case JS_GET_TIMEOUT:
 534                 return put_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);
 535
 536         case JSIOCGVERSION:
 537                 return put_user(JS_VERSION, (__u32 __user *) argp);
 538
 539         case JSIOCGAXES:
 540                 return put_user(joydev->nabs, (__u8 __user *) argp);
 541
 542         case JSIOCGBUTTONS:
 543                 return put_user(joydev->nkey, (__u8 __user *) argp);
 544
 545         case JSIOCSCORR:
 546                 if (copy_from_user(joydev->corr, argp,
 547                               sizeof(joydev->corr[0]) * joydev->nabs))
 548                         return -EFAULT;
 549
 550                 for (i = 0; i < joydev->nabs; i++) {
 551                         int val = input_abs_get_val(dev, joydev->abspam[i]);
 552                         joydev->abs[i] = joydev_correct(val, &joydev->corr[i]);
 553                 }
 554                 return 0;
 555
 556         case JSIOCGCORR:
 557                 return copy_to_user(argp, joydev->corr,
 558                         sizeof(joydev->corr[0]) * joydev->nabs) ? -EFAULT : 0;
 559
 560         }
 561
 562         /*
 563          * Process variable-sized commands (the axis and button map commands
 564          * are considered variable-sized to decouple them from the values of
 565          * ABS_MAX and KEY_MAX).
 566          */
 567         switch (cmd & ~IOCSIZE_MASK) {
 568
 569         case (JSIOCSAXMAP & ~IOCSIZE_MASK):
 570                 return joydev_handle_JSIOCSAXMAP(joydev, argp, _IOC_SIZE(cmd));
 571
 572         case (JSIOCGAXMAP & ~IOCSIZE_MASK):
 573                 len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->abspam));
 574                 return copy_to_user(argp, joydev->abspam, len) ? -EFAULT : len;
 575
 576         case (JSIOCSBTNMAP & ~IOCSIZE_MASK):
 577                 return joydev_handle_JSIOCSBTNMAP(joydev, argp, _IOC_SIZE(cmd));
 578
 579         case (JSIOCGBTNMAP & ~IOCSIZE_MASK):
 580                 len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->keypam));
 581                 return copy_to_user(argp, joydev->keypam, len) ? -EFAULT : len;
 582
 583         case JSIOCGNAME(0):
 584                 name = dev->name;
 585                 if (!name)
 586                         return 0;
 587
 588                 len = min_t(size_t, _IOC_SIZE(cmd), strlen(name) + 1);
 589                 return copy_to_user(argp, name, len) ? -EFAULT : len;
 590         }
 591
 592         return -EINVAL;
 593 }
 594
 595 #ifdef CONFIG_COMPAT
 596 static long joydev_compat_ioctl(struct file *file,
 597                                 unsigned int cmd, unsigned long arg)
 598 {
 599         struct joydev_client *client = file->private_data;
 600         struct joydev *joydev = client->joydev;
 601         void __user *argp = (void __user *)arg;
 602         s32 tmp32;
 603         struct JS_DATA_SAVE_TYPE_32 ds32;
 604         int retval;
 605
 606         retval = mutex_lock_interruptible(&joydev->mutex);
 607         if (retval)
 608                 return retval;
 609
 610         if (!joydev->exist) {
 611                 retval = -ENODEV;
 612                 goto out;
 613         }
 614
 615         switch (cmd) {
 616
 617         case JS_SET_TIMELIMIT:
 618                 retval = get_user(tmp32, (s32 __user *) arg);
 619                 if (retval == 0)
 620                         joydev->glue.JS_TIMELIMIT = tmp32;
 621                 break;
 622
 623         case JS_GET_TIMELIMIT:
 624                 tmp32 = joydev->glue.JS_TIMELIMIT;
 625                 retval = put_user(tmp32, (s32 __user *) arg);
 626                 break;
 627
 628         case JS_SET_ALL:
 629                 retval = copy_from_user(&ds32, argp,
 630                                         sizeof(ds32)) ? -EFAULT : 0;
 631                 if (retval == 0) {
 632                         joydev->glue.JS_TIMEOUT    = ds32.JS_TIMEOUT;
 633                         joydev->glue.BUSY          = ds32.BUSY;
 634                         joydev->glue.JS_EXPIRETIME = ds32.JS_EXPIRETIME;
 635                         joydev->glue.JS_TIMELIMIT  = ds32.JS_TIMELIMIT;
 636                         joydev->glue.JS_SAVE       = ds32.JS_SAVE;
 637                         joydev->glue.JS_CORR       = ds32.JS_CORR;
 638                 }
 639                 break;
 640
 641         case JS_GET_ALL:
 642                 ds32.JS_TIMEOUT    = joydev->glue.JS_TIMEOUT;
 643                 ds32.BUSY          = joydev->glue.BUSY;
 644                 ds32.JS_EXPIRETIME = joydev->glue.JS_EXPIRETIME;
 645                 ds32.JS_TIMELIMIT  = joydev->glue.JS_TIMELIMIT;
 646                 ds32.JS_SAVE       = joydev->glue.JS_SAVE;
 647                 ds32.JS_CORR       = joydev->glue.JS_CORR;
 648
 649                 retval = copy_to_user(argp, &ds32, sizeof(ds32)) ? -EFAULT : 0;
 650                 break;
 651
 652         default:
 653                 retval = joydev_ioctl_common(joydev, cmd, argp);
 654                 break;
 655         }
 656
 657  out:
 658         mutex_unlock(&joydev->mutex);
 659         return retval;
 660 }
 661 #endif /* CONFIG_COMPAT */
 662
 663 static long joydev_ioctl(struct file *file,
 664                          unsigned int cmd, unsigned long arg)
 665 {
 666         struct joydev_client *client = file->private_data;
 667         struct joydev *joydev = client->joydev;
 668         void __user *argp = (void __user *)arg;
 669         int retval;
 670
 671         retval = mutex_lock_interruptible(&joydev->mutex);
 672         if (retval)
 673                 return retval;
 674
 675         if (!joydev->exist) {
 676                 retval = -ENODEV;
 677                 goto out;
 678         }
 679
 680         switch (cmd) {
 681
 682         case JS_SET_TIMELIMIT:
 683                 retval = get_user(joydev->glue.JS_TIMELIMIT,
 684                                   (long __user *) arg);
 685                 break;
 686
 687         case JS_GET_TIMELIMIT:
 688                 retval = put_user(joydev->glue.JS_TIMELIMIT,
 689                                   (long __user *) arg);
 690                 break;
 691
 692         case JS_SET_ALL:
 693                 retval = copy_from_user(&joydev->glue, argp,
 694                                         sizeof(joydev->glue)) ? -EFAULT : 0;
 695                 break;
 696
 697         case JS_GET_ALL:
 698                 retval = copy_to_user(argp, &joydev->glue,
 699                                       sizeof(joydev->glue)) ? -EFAULT : 0;
 700                 break;
 701
 702         default:
 703                 retval = joydev_ioctl_common(joydev, cmd, argp);
 704                 break;
 705         }
 706  out:
 707         mutex_unlock(&joydev->mutex);
 708         return retval;
 709 }
 710
 711 static const struct file_operations joydev_fops = {
 712         .owner          = THIS_MODULE,
 713         .read           = joydev_read,
 714         .poll           = joydev_poll,
 715         .open           = joydev_open,
 716         .release        = joydev_release,
 717         .unlocked_ioctl = joydev_ioctl,
 718 #ifdef CONFIG_COMPAT
 719         .compat_ioctl   = joydev_compat_ioctl,
 720 #endif
 721         .fasync         = joydev_fasync,
 722         .llseek         = no_llseek,
 723 };
 724
 725 /*
 726  * Mark device non-existent. This disables writes, ioctls and
 727  * prevents new users from opening the device. Already posted
 728  * blocking reads will stay, however new ones will fail.
 729  */
 730 static void joydev_mark_dead(struct joydev *joydev)
 731 {
 732         mutex_lock(&joydev->mutex);
 733         joydev->exist = false;
 734         mutex_unlock(&joydev->mutex);
 735 }
 736
 737 static void joydev_cleanup(struct joydev *joydev)
 738 {
 739         struct input_handle *handle = &joydev->handle;
 740
 741         joydev_mark_dead(joydev);
 742         joydev_hangup(joydev);
 743
 744         /* joydev is marked dead so no one else accesses joydev->open */
 745         if (joydev->open)
 746                 input_close_device(handle);
 747 }
 748
 749 /*
 750  * These codes are copied from from hid-ids.h, unfortunately there is no common
 751  * usb_ids/bt_ids.h header.
 752  */
 753 #define USB_VENDOR_ID_SONY                      0x054c
 754 #define USB_DEVICE_ID_SONY_PS3_CONTROLLER               0x0268
 755 #define USB_DEVICE_ID_SONY_PS4_CONTROLLER               0x05c4
 756 #define USB_DEVICE_ID_SONY_PS4_CONTROLLER_2             0x09cc
 757 #define USB_DEVICE_ID_SONY_PS4_CONTROLLER_DONGLE        0x0ba0
 758
 759 #define USB_VENDOR_ID_THQ                       0x20d6
 760 #define USB_DEVICE_ID_THQ_PS3_UDRAW                     0xcb17
 761
 762 #define ACCEL_DEV(vnd, prd)                                             \
 763         {                                                               \
 764                 .flags = INPUT_DEVICE_ID_MATCH_VENDOR |                 \
 765                                 INPUT_DEVICE_ID_MATCH_PRODUCT |         \
 766                                 INPUT_DEVICE_ID_MATCH_PROPBIT,          \
 767                 .vendor = (vnd),                                        \
 768                 .product = (prd),                                       \
 769                 .propbit = { BIT_MASK(INPUT_PROP_ACCELEROMETER) },      \
 770         }
 771
 772 static const struct input_device_id joydev_blacklist[] = {
 773         /* Avoid touchpads and touchscreens */
 774         {
 775                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 776                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
 777                 .evbit = { BIT_MASK(EV_KEY) },
 778                 .keybit = { [BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) },
 779         },
 780         /* Avoid tablets, digitisers and similar devices */
 781         {
 782                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
 783                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
 784                 .evbit = { BIT_MASK(EV_KEY) },
 785                 .keybit = { [BIT_WORD(BTN_DIGI)] = BIT_MASK(BTN_DIGI) },
 786         },
 787         /* Disable accelerometers on composite devices */
 788         ACCEL_DEV(USB_VENDOR_ID_SONY, USB_DEVICE_ID_SONY_PS3_CONTROLLER),
 789         ACCEL_DEV(USB_VENDOR_ID_SONY, USB_DEVICE_ID_SONY_PS4_CONTROLLER),
 790         ACCEL_DEV(USB_VENDOR_ID_SONY, USB_DEVICE_ID_SONY_PS4_CONTROLLER_2),
 791         ACCEL_DEV(USB_VENDOR_ID_SONY, USB_DEVICE_ID_SONY_PS4_CONTROLLER_DONGLE),
 792         ACCEL_DEV(USB_VENDOR_ID_THQ, USB_DEVICE_ID_THQ_PS3_UDRAW),
 793         { /* sentinel */ }
 794 };
 795
 796 static bool joydev_dev_is_blacklisted(struct input_dev *dev)
 797 {
 798         const struct input_device_id *id;
 799
 800         for (id = joydev_blacklist; id->flags; id++) {
 801                 if (input_match_device_id(dev, id)) {
 802                         dev_dbg(&dev->dev,
 803                                 "joydev: blacklisting '%s'\n", dev->name);
 804                         return true;
 805                 }
 806         }
 807
 808         return false;
 809 }
 810
 811 static bool joydev_dev_is_absolute_mouse(struct input_dev *dev)
 812 {
 813         DECLARE_BITMAP(jd_scratch, KEY_CNT);
 814         bool ev_match = false;
 815
 816         BUILD_BUG_ON(ABS_CNT > KEY_CNT || EV_CNT > KEY_CNT);
 817
 818         /*
 819          * Virtualization (VMware, etc) and remote management (HP
 820          * ILO2) solutions use absolute coordinates for their virtual
 821          * pointing devices so that there is one-to-one relationship
 822          * between pointer position on the host screen and virtual
 823          * guest screen, and so their mice use ABS_X, ABS_Y and 3
 824          * primary button events. This clashes with what joydev
 825          * considers to be joysticks (a device with at minimum ABS_X
 826          * axis).
 827          *
 828          * Here we are trying to separate absolute mice from
 829          * joysticks. A device is, for joystick detection purposes,
 830          * considered to be an absolute mouse if the following is
 831          * true:
 832          *
 833          * 1) Event types are exactly
 834          *      EV_ABS, EV_KEY and EV_SYN
 835          *    or
 836          *      EV_ABS, EV_KEY, EV_SYN and EV_MSC
 837          *    or
 838          *      EV_ABS, EV_KEY, EV_SYN, EV_MSC and EV_REL.
 839          * 2) Absolute events are exactly ABS_X and ABS_Y.
 840          * 3) Keys are exactly BTN_LEFT, BTN_RIGHT and BTN_MIDDLE.
 841          * 4) Device is not on "Amiga" bus.
 842          */
 843
 844         bitmap_zero(jd_scratch, EV_CNT);
 845         /* VMware VMMouse, HP ILO2 */
 846         __set_bit(EV_ABS, jd_scratch);
 847         __set_bit(EV_KEY, jd_scratch);
 848         __set_bit(EV_SYN, jd_scratch);
 849         if (bitmap_equal(jd_scratch, dev->evbit, EV_CNT))
 850                 ev_match = true;
 851
 852         /* HP ILO2, AMI BMC firmware */
 853         __set_bit(EV_MSC, jd_scratch);
 854         if (bitmap_equal(jd_scratch, dev->evbit, EV_CNT))
 855                 ev_match = true;
 856
 857         /* VMware Virtual USB Mouse, QEMU USB Tablet, ATEN BMC firmware */
 858         __set_bit(EV_REL, jd_scratch);
 859         if (bitmap_equal(jd_scratch, dev->evbit, EV_CNT))
 860                 ev_match = true;
 861
 862         if (!ev_match)
 863                 return false;
 864
 865         bitmap_zero(jd_scratch, ABS_CNT);
 866         __set_bit(ABS_X, jd_scratch);
 867         __set_bit(ABS_Y, jd_scratch);
 868         if (!bitmap_equal(dev->absbit, jd_scratch, ABS_CNT))
 869                 return false;
 870
 871         bitmap_zero(jd_scratch, KEY_CNT);
 872         __set_bit(BTN_LEFT, jd_scratch);
 873         __set_bit(BTN_RIGHT, jd_scratch);
 874         __set_bit(BTN_MIDDLE, jd_scratch);
 875
 876         if (!bitmap_equal(dev->keybit, jd_scratch, KEY_CNT))
 877                 return false;
 878
 879         /*
 880          * Amiga joystick (amijoy) historically uses left/middle/right
 881          * button events.
 882          */
 883         if (dev->id.bustype == BUS_AMIGA)
 884                 return false;
 885
 886         return true;
 887 }
 888
 889 static bool joydev_match(struct input_handler *handler, struct input_dev *dev)
 890 {
 891         /* Disable blacklisted devices */
 892         if (joydev_dev_is_blacklisted(dev))
 893                 return false;
 894
 895         /* Avoid absolute mice */
 896         if (joydev_dev_is_absolute_mouse(dev))
 897                 return false;
 898
 899         return true;
 900 }
 901
 902 static int joydev_connect(struct input_handler *handler, struct input_dev *dev,
 903                           const struct input_device_id *id)
 904 {
 905         struct joydev *joydev;
 906         int i, j, t, minor, dev_no;
 907         int error;
 908
 909         minor = input_get_new_minor(JOYDEV_MINOR_BASE, JOYDEV_MINORS, true);
 910         if (minor < 0) {
 911                 error = minor;
 912                 pr_err("failed to reserve new minor: %d\n", error);
 913                 return error;
 914         }
 915
 916         joydev = kzalloc(sizeof(struct joydev), GFP_KERNEL);
 917         if (!joydev) {
 918                 error = -ENOMEM;
 919                 goto err_free_minor;
 920         }
 921
 922         INIT_LIST_HEAD(&joydev->client_list);
 923         spin_lock_init(&joydev->client_lock);
 924         mutex_init(&joydev->mutex);
 925         init_waitqueue_head(&joydev->wait);
 926         joydev->exist = true;
 927
 928         dev_no = minor;
 929         /* Normalize device number if it falls into legacy range */
 930         if (dev_no < JOYDEV_MINOR_BASE + JOYDEV_MINORS)
 931                 dev_no -= JOYDEV_MINOR_BASE;
 932         dev_set_name(&joydev->dev, "js%d", dev_no);
 933
 934         joydev->handle.dev = input_get_device(dev);
 935         joydev->handle.name = dev_name(&joydev->dev);
 936         joydev->handle.handler = handler;
 937         joydev->handle.private = joydev;
 938
 939         for_each_set_bit(i, dev->absbit, ABS_CNT) {
 940                 joydev->absmap[i] = joydev->nabs;
 941                 joydev->abspam[joydev->nabs] = i;
 942                 joydev->nabs++;
 943         }
 944
 945         for (i = BTN_JOYSTICK - BTN_MISC; i < KEY_MAX - BTN_MISC + 1; i++)
 946                 if (test_bit(i + BTN_MISC, dev->keybit)) {
 947                         joydev->keymap[i] = joydev->nkey;
 948                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
 949                         joydev->nkey++;
 950                 }
 951
 952         for (i = 0; i < BTN_JOYSTICK - BTN_MISC; i++)
 953                 if (test_bit(i + BTN_MISC, dev->keybit)) {
 954                         joydev->keymap[i] = joydev->nkey;
 955                         joydev->keypam[joydev->nkey] = i + BTN_MISC;
 956                         joydev->nkey++;
 957                 }
 958
 959         for (i = 0; i < joydev->nabs; i++) {
 960                 j = joydev->abspam[i];
 961                 if (input_abs_get_max(dev, j) == input_abs_get_min(dev, j)) {
 962                         joydev->corr[i].type = JS_CORR_NONE;
 963                         continue;
 964                 }
 965                 joydev->corr[i].type = JS_CORR_BROKEN;
 966                 joydev->corr[i].prec = input_abs_get_fuzz(dev, j);
 967
 968                 t = (input_abs_get_max(dev, j) + input_abs_get_min(dev, j)) / 2;
 969                 joydev->corr[i].coef[0] = t - input_abs_get_flat(dev, j);
 970                 joydev->corr[i].coef[1] = t + input_abs_get_flat(dev, j);
 971
 972                 t = (input_abs_get_max(dev, j) - input_abs_get_min(dev, j)) / 2
 973                         - 2 * input_abs_get_flat(dev, j);
 974                 if (t) {
 975                         joydev->corr[i].coef[2] = (1 << 29) / t;
 976                         joydev->corr[i].coef[3] = (1 << 29) / t;
 977                 }
 978         }
 979
 980         joydev->dev.devt = MKDEV(INPUT_MAJOR, minor);
 981         joydev->dev.class = &input_class;
 982         joydev->dev.parent = &dev->dev;
 983         joydev->dev.release = joydev_free;
 984         device_initialize(&joydev->dev);
 985
 986         error = input_register_handle(&joydev->handle);
 987         if (error)
 988                 goto err_free_joydev;
 989
 990         cdev_init(&joydev->cdev, &joydev_fops);
 991
 992         error = cdev_device_add(&joydev->cdev, &joydev->dev);
 993         if (error)
 994                 goto err_cleanup_joydev;
 995
 996         return 0;
 997
 998  err_cleanup_joydev:
 999         joydev_cleanup(joydev);
1000         input_unregister_handle(&joydev->handle);
1001  err_free_joydev:
1002         put_device(&joydev->dev);
1003  err_free_minor:
1004         input_free_minor(minor);
1005         return error;
1006 }
1007
1008 static void joydev_disconnect(struct input_handle *handle)
1009 {
1010         struct joydev *joydev = handle->private;
1011
1012         cdev_device_del(&joydev->cdev, &joydev->dev);
1013         joydev_cleanup(joydev);
1014         input_free_minor(MINOR(joydev->dev.devt));
1015         input_unregister_handle(handle);
1016         put_device(&joydev->dev);
1017 }
1018
1019 static const struct input_device_id joydev_ids[] = {
1020         {
1021                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1022                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1023                 .evbit = { BIT_MASK(EV_ABS) },
1024                 .absbit = { BIT_MASK(ABS_X) },
1025         },
1026         {
1027                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1028                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1029                 .evbit = { BIT_MASK(EV_ABS) },
1030                 .absbit = { BIT_MASK(ABS_Z) },
1031         },
1032         {
1033                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1034                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1035                 .evbit = { BIT_MASK(EV_ABS) },
1036                 .absbit = { BIT_MASK(ABS_WHEEL) },
1037         },
1038         {
1039                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1040                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1041                 .evbit = { BIT_MASK(EV_ABS) },
1042                 .absbit = { BIT_MASK(ABS_THROTTLE) },
1043         },
1044         {
1045                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1046                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
1047                 .evbit = { BIT_MASK(EV_KEY) },
1048                 .keybit = {[BIT_WORD(BTN_JOYSTICK)] = BIT_MASK(BTN_JOYSTICK) },
1049         },
1050         {
1051                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1052                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
1053                 .evbit = { BIT_MASK(EV_KEY) },
1054                 .keybit = { [BIT_WORD(BTN_GAMEPAD)] = BIT_MASK(BTN_GAMEPAD) },
1055         },
1056         {
1057                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1058                                 INPUT_DEVICE_ID_MATCH_KEYBIT,
1059                 .evbit = { BIT_MASK(EV_KEY) },
1060                 .keybit = { [BIT_WORD(BTN_TRIGGER_HAPPY)] = BIT_MASK(BTN_TRIGGER_HAPPY) },
1061         },
1062         { }     /* Terminating entry */
1063 };
1064
1065 MODULE_DEVICE_TABLE(input, joydev_ids);
1066
1067 static struct input_handler joydev_handler = {
1068         .event          = joydev_event,
1069         .match          = joydev_match,
1070         .connect        = joydev_connect,
1071         .disconnect     = joydev_disconnect,
1072         .legacy_minors  = true,
1073         .minor          = JOYDEV_MINOR_BASE,
1074         .name           = "joydev",
1075         .id_table       = joydev_ids,
1076 };
1077
1078 static int __init joydev_init(void)
1079 {
1080         return input_register_handler(&joydev_handler);
1081 }
1082
1083 static void __exit joydev_exit(void)
1084 {
1085         input_unregister_handler(&joydev_handler);
1086 }
1087
1088 module_init(joydev_init);
1089 module_exit(joydev_exit);