git.oblomov.eu Git - linux-2.6/blob - drivers/input/misc/uinput.c

   1 /*
   2  *  User level driver support for input subsystem
   3  *
   4  * Heavily based on evdev.c by Vojtech Pavlik
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  19  *
  20  * Author: Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
  21  *
  22  * Changes/Revisions:
  23  *      0.2     16/10/2004 (Micah Dowty <micah@navi.cx>)
  24  *              - added force feedback support
  25  *              - added UI_SET_PHYS
  26  *      0.1     20/06/2002
  27  *              - first public version
  28  */
  29 #include <linux/poll.h>
  30 #include <linux/slab.h>
  31 #include <linux/module.h>
  32 #include <linux/init.h>
  33 #include <linux/input.h>
  34 #include <linux/smp_lock.h>
  35 #include <linux/fs.h>
  36 #include <linux/miscdevice.h>
  37 #include <linux/uinput.h>
  38
  39 static int uinput_dev_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)
  40 {
  41         struct uinput_device    *udev;
  42
  43         udev = dev->private;
  44
  45         udev->buff[udev->head].type = type;
  46         udev->buff[udev->head].code = code;
  47         udev->buff[udev->head].value = value;
  48         do_gettimeofday(&udev->buff[udev->head].time);
  49         udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;
  50
  51         wake_up_interruptible(&udev->waitq);
  52
  53         return 0;
  54 }
  55
  56 static int uinput_request_alloc_id(struct uinput_device *udev, struct uinput_request *request)
  57 {
  58         /* Atomically allocate an ID for the given request. Returns 0 on success. */
  59         int id;
  60         int err = -1;
  61
  62         spin_lock(&udev->requests_lock);
  63
  64         for (id = 0; id < UINPUT_NUM_REQUESTS; id++)
  65                 if (!udev->requests[id]) {
  66                         request->id = id;
  67                         udev->requests[id] = request;
  68                         err = 0;
  69                         break;
  70                 }
  71
  72         spin_unlock(&udev->requests_lock);
  73         return err;
  74 }
  75
  76 static struct uinput_request* uinput_request_find(struct uinput_device *udev, int id)
  77 {
  78         /* Find an input request, by ID. Returns NULL if the ID isn't valid. */
  79         if (id >= UINPUT_NUM_REQUESTS || id < 0)
  80                 return NULL;
  81         return udev->requests[id];
  82 }
  83
  84 static inline int uinput_request_reserve_slot(struct uinput_device *udev, struct uinput_request *request)
  85 {
  86         /* Allocate slot. If none are available right away, wait. */
  87         return wait_event_interruptible(udev->requests_waitq,
  88                                         !uinput_request_alloc_id(udev, request));
  89 }
  90
  91 static void uinput_request_done(struct uinput_device *udev, struct uinput_request *request)
  92 {
  93         complete(&request->done);
  94
  95         /* Mark slot as available */
  96         udev->requests[request->id] = NULL;
  97         wake_up_interruptible(&udev->requests_waitq);
  98 }
  99
 100 static int uinput_request_submit(struct input_dev *dev, struct uinput_request *request)
 101 {
 102         int retval;
 103
 104         /* Tell our userspace app about this new request by queueing an input event */
 105         uinput_dev_event(dev, EV_UINPUT, request->code, request->id);
 106
 107         /* Wait for the request to complete */
 108         retval = wait_for_completion_interruptible(&request->done);
 109         if (!retval)
 110                 retval = request->retval;
 111
 112         return retval;
 113 }
 114
 115 static int uinput_dev_upload_effect(struct input_dev *dev, struct ff_effect *effect)
 116 {
 117         struct uinput_request request;
 118         int retval;
 119
 120         if (!test_bit(EV_FF, dev->evbit))
 121                 return -ENOSYS;
 122
 123         request.id = -1;
 124         init_completion(&request.done);
 125         request.code = UI_FF_UPLOAD;
 126         request.u.effect = effect;
 127
 128         retval = uinput_request_reserve_slot(dev->private, &request);
 129         if (!retval)
 130                 retval = uinput_request_submit(dev, &request);
 131
 132         return retval;
 133 }
 134
 135 static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
 136 {
 137         struct uinput_request request;
 138         int retval;
 139
 140         if (!test_bit(EV_FF, dev->evbit))
 141                 return -ENOSYS;
 142
 143         request.id = -1;
 144         init_completion(&request.done);
 145         request.code = UI_FF_ERASE;
 146         request.u.effect_id = effect_id;
 147
 148         retval = uinput_request_reserve_slot(dev->private, &request);
 149         if (!retval)
 150                 retval = uinput_request_submit(dev, &request);
 151
 152         return retval;
 153 }
 154
 155 static int uinput_create_device(struct uinput_device *udev)
 156 {
 157         if (!udev->dev->name) {
 158                 printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
 159                 return -EINVAL;
 160         }
 161
 162         udev->dev->event = uinput_dev_event;
 163         udev->dev->upload_effect = uinput_dev_upload_effect;
 164         udev->dev->erase_effect = uinput_dev_erase_effect;
 165         udev->dev->private = udev;
 166
 167         init_waitqueue_head(&udev->waitq);
 168
 169         input_register_device(udev->dev);
 170
 171         set_bit(UIST_CREATED, &udev->state);
 172
 173         return 0;
 174 }
 175
 176 static int uinput_destroy_device(struct uinput_device *udev)
 177 {
 178         if (!test_bit(UIST_CREATED, &udev->state)) {
 179                 printk(KERN_WARNING "%s: create the device first\n", UINPUT_NAME);
 180                 return -EINVAL;
 181         }
 182
 183         input_unregister_device(udev->dev);
 184
 185         clear_bit(UIST_CREATED, &udev->state);
 186
 187         return 0;
 188 }
 189
 190 static int uinput_open(struct inode *inode, struct file *file)
 191 {
 192         struct uinput_device    *newdev;
 193         struct input_dev        *newinput;
 194
 195         newdev = kmalloc(sizeof(struct uinput_device), GFP_KERNEL);
 196         if (!newdev)
 197                 goto error;
 198         memset(newdev, 0, sizeof(struct uinput_device));
 199         spin_lock_init(&newdev->requests_lock);
 200         init_waitqueue_head(&newdev->requests_waitq);
 201
 202         newinput = kmalloc(sizeof(struct input_dev), GFP_KERNEL);
 203         if (!newinput)
 204                 goto cleanup;
 205         memset(newinput, 0, sizeof(struct input_dev));
 206
 207         newdev->dev = newinput;
 208
 209         file->private_data = newdev;
 210
 211         return 0;
 212 cleanup:
 213         kfree(newdev);
 214 error:
 215         return -ENOMEM;
 216 }
 217
 218 static int uinput_validate_absbits(struct input_dev *dev)
 219 {
 220         unsigned int cnt;
 221         int retval = 0;
 222
 223         for (cnt = 0; cnt < ABS_MAX + 1; cnt++) {
 224                 if (!test_bit(cnt, dev->absbit))
 225                         continue;
 226
 227                 if ((dev->absmax[cnt] <= dev->absmin[cnt])) {
 228                         printk(KERN_DEBUG
 229                                 "%s: invalid abs[%02x] min:%d max:%d\n",
 230                                 UINPUT_NAME, cnt,
 231                                 dev->absmin[cnt], dev->absmax[cnt]);
 232                         retval = -EINVAL;
 233                         break;
 234                 }
 235
 236                 if (dev->absflat[cnt] > (dev->absmax[cnt] - dev->absmin[cnt])) {
 237                         printk(KERN_DEBUG
 238                                 "%s: absflat[%02x] out of range: %d "
 239                                 "(min:%d/max:%d)\n",
 240                                 UINPUT_NAME, cnt, dev->absflat[cnt],
 241                                 dev->absmin[cnt], dev->absmax[cnt]);
 242                         retval = -EINVAL;
 243                         break;
 244                 }
 245         }
 246         return retval;
 247 }
 248
 249 static int uinput_alloc_device(struct file *file, const char __user *buffer, size_t count)
 250 {
 251         struct uinput_user_dev  *user_dev;
 252         struct input_dev        *dev;
 253         struct uinput_device    *udev;
 254         char                    *name;
 255         int                     size;
 256         int                     retval;
 257
 258         retval = count;
 259
 260         udev = file->private_data;
 261         dev = udev->dev;
 262
 263         user_dev = kmalloc(sizeof(struct uinput_user_dev), GFP_KERNEL);
 264         if (!user_dev) {
 265                 retval = -ENOMEM;
 266                 goto exit;
 267         }
 268
 269         if (copy_from_user(user_dev, buffer, sizeof(struct uinput_user_dev))) {
 270                 retval = -EFAULT;
 271                 goto exit;
 272         }
 273
 274         if (dev->name)
 275                 kfree(dev->name);
 276
 277         size = strnlen(user_dev->name, UINPUT_MAX_NAME_SIZE) + 1;
 278         dev->name = name = kmalloc(size, GFP_KERNEL);
 279         if (!name) {
 280                 retval = -ENOMEM;
 281                 goto exit;
 282         }
 283         strlcpy(name, user_dev->name, size);
 284
 285         dev->id.bustype = user_dev->id.bustype;
 286         dev->id.vendor  = user_dev->id.vendor;
 287         dev->id.product = user_dev->id.product;
 288         dev->id.version = user_dev->id.version;
 289         dev->ff_effects_max = user_dev->ff_effects_max;
 290
 291         size = sizeof(int) * (ABS_MAX + 1);
 292         memcpy(dev->absmax, user_dev->absmax, size);
 293         memcpy(dev->absmin, user_dev->absmin, size);
 294         memcpy(dev->absfuzz, user_dev->absfuzz, size);
 295         memcpy(dev->absflat, user_dev->absflat, size);
 296
 297         /* check if absmin/absmax/absfuzz/absflat are filled as
 298          * told in Documentation/input/input-programming.txt */
 299         if (test_bit(EV_ABS, dev->evbit)) {
 300                 int err = uinput_validate_absbits(dev);
 301                 if (err < 0) {
 302                         retval = err;
 303                         kfree(dev->name);
 304                 }
 305         }
 306
 307 exit:
 308         kfree(user_dev);
 309         return retval;
 310 }
 311
 312 static ssize_t uinput_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
 313 {
 314         struct uinput_device *udev = file->private_data;
 315
 316         if (test_bit(UIST_CREATED, &udev->state)) {
 317                 struct input_event      ev;
 318
 319                 if (copy_from_user(&ev, buffer, sizeof(struct input_event)))
 320                         return -EFAULT;
 321                 input_event(udev->dev, ev.type, ev.code, ev.value);
 322         } else
 323                 count = uinput_alloc_device(file, buffer, count);
 324
 325         return count;
 326 }
 327
 328 static ssize_t uinput_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
 329 {
 330         struct uinput_device *udev = file->private_data;
 331         int retval = 0;
 332
 333         if (!test_bit(UIST_CREATED, &udev->state))
 334                 return -ENODEV;
 335
 336         if (udev->head == udev->tail && (file->f_flags & O_NONBLOCK))
 337                 return -EAGAIN;
 338
 339         retval = wait_event_interruptible(udev->waitq,
 340                         udev->head != udev->tail || !test_bit(UIST_CREATED, &udev->state));
 341         if (retval)
 342                 return retval;
 343
 344         if (!test_bit(UIST_CREATED, &udev->state))
 345                 return -ENODEV;
 346
 347         while ((udev->head != udev->tail) &&
 348             (retval + sizeof(struct input_event) <= count)) {
 349                 if (copy_to_user(buffer + retval, &udev->buff[udev->tail], sizeof(struct input_event)))
 350                         return -EFAULT;
 351                 udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
 352                 retval += sizeof(struct input_event);
 353         }
 354
 355         return retval;
 356 }
 357
 358 static unsigned int uinput_poll(struct file *file, poll_table *wait)
 359 {
 360         struct uinput_device *udev = file->private_data;
 361
 362         poll_wait(file, &udev->waitq, wait);
 363
 364         if (udev->head != udev->tail)
 365                 return POLLIN | POLLRDNORM;
 366
 367         return 0;
 368 }
 369
 370 static int uinput_burn_device(struct uinput_device *udev)
 371 {
 372         if (test_bit(UIST_CREATED, &udev->state))
 373                 uinput_destroy_device(udev);
 374
 375         if (udev->dev->name)
 376                 kfree(udev->dev->name);
 377         if (udev->dev->phys)
 378                 kfree(udev->dev->phys);
 379
 380         kfree(udev->dev);
 381         kfree(udev);
 382
 383         return 0;
 384 }
 385
 386 static int uinput_close(struct inode *inode, struct file *file)
 387 {
 388         uinput_burn_device(file->private_data);
 389         return 0;
 390 }
 391
 392 static int uinput_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 393 {
 394         int                     retval = 0;
 395         struct uinput_device    *udev;
 396         void __user             *p = (void __user *)arg;
 397         struct uinput_ff_upload ff_up;
 398         struct uinput_ff_erase  ff_erase;
 399         struct uinput_request   *req;
 400         int                     length;
 401         char                    *phys;
 402
 403         udev = file->private_data;
 404
 405         /* device attributes can not be changed after the device is created */
 406         switch (cmd) {
 407                 case UI_SET_EVBIT:
 408                 case UI_SET_KEYBIT:
 409                 case UI_SET_RELBIT:
 410                 case UI_SET_ABSBIT:
 411                 case UI_SET_MSCBIT:
 412                 case UI_SET_LEDBIT:
 413                 case UI_SET_SNDBIT:
 414                 case UI_SET_FFBIT:
 415                 case UI_SET_PHYS:
 416                         if (test_bit(UIST_CREATED, &udev->state))
 417                                 return -EINVAL;
 418         }
 419
 420         switch (cmd) {
 421                 case UI_DEV_CREATE:
 422                         retval = uinput_create_device(udev);
 423                         break;
 424
 425                 case UI_DEV_DESTROY:
 426                         retval = uinput_destroy_device(udev);
 427                         break;
 428
 429                 case UI_SET_EVBIT:
 430                         if (arg > EV_MAX) {
 431                                 retval = -EINVAL;
 432                                 break;
 433                         }
 434                         set_bit(arg, udev->dev->evbit);
 435                         break;
 436
 437                 case UI_SET_KEYBIT:
 438                         if (arg > KEY_MAX) {
 439                                 retval = -EINVAL;
 440                                 break;
 441                         }
 442                         set_bit(arg, udev->dev->keybit);
 443                         break;
 444
 445                 case UI_SET_RELBIT:
 446                         if (arg > REL_MAX) {
 447                                 retval = -EINVAL;
 448                                 break;
 449                         }
 450                         set_bit(arg, udev->dev->relbit);
 451                         break;
 452
 453                 case UI_SET_ABSBIT:
 454                         if (arg > ABS_MAX) {
 455                                 retval = -EINVAL;
 456                                 break;
 457                         }
 458                         set_bit(arg, udev->dev->absbit);
 459                         break;
 460
 461                 case UI_SET_MSCBIT:
 462                         if (arg > MSC_MAX) {
 463                                 retval = -EINVAL;
 464                                 break;
 465                         }
 466                         set_bit(arg, udev->dev->mscbit);
 467                         break;
 468
 469                 case UI_SET_LEDBIT:
 470                         if (arg > LED_MAX) {
 471                                 retval = -EINVAL;
 472                                 break;
 473                         }
 474                         set_bit(arg, udev->dev->ledbit);
 475                         break;
 476
 477                 case UI_SET_SNDBIT:
 478                         if (arg > SND_MAX) {
 479                                 retval = -EINVAL;
 480                                 break;
 481                         }
 482                         set_bit(arg, udev->dev->sndbit);
 483                         break;
 484
 485                 case UI_SET_FFBIT:
 486                         if (arg > FF_MAX) {
 487                                 retval = -EINVAL;
 488                                 break;
 489                         }
 490                         set_bit(arg, udev->dev->ffbit);
 491                         break;
 492
 493                 case UI_SET_PHYS:
 494                         length = strnlen_user(p, 1024);
 495                         if (length <= 0) {
 496                                 retval = -EFAULT;
 497                                 break;
 498                         }
 499                         kfree(udev->dev->phys);
 500                         udev->dev->phys = phys = kmalloc(length, GFP_KERNEL);
 501                         if (!phys) {
 502                                 retval = -ENOMEM;
 503                                 break;
 504                         }
 505                         if (copy_from_user(phys, p, length)) {
 506                                 udev->dev->phys = NULL;
 507                                 kfree(phys);
 508                                 retval = -EFAULT;
 509                                 break;
 510                         }
 511                         phys[length - 1] = '\0';
 512                         break;
 513
 514                 case UI_BEGIN_FF_UPLOAD:
 515                         if (copy_from_user(&ff_up, p, sizeof(ff_up))) {
 516                                 retval = -EFAULT;
 517                                 break;
 518                         }
 519                         req = uinput_request_find(udev, ff_up.request_id);
 520                         if (!(req && req->code == UI_FF_UPLOAD && req->u.effect)) {
 521                                 retval = -EINVAL;
 522                                 break;
 523                         }
 524                         ff_up.retval = 0;
 525                         memcpy(&ff_up.effect, req->u.effect, sizeof(struct ff_effect));
 526                         if (copy_to_user(p, &ff_up, sizeof(ff_up))) {
 527                                 retval = -EFAULT;
 528                                 break;
 529                         }
 530                         break;
 531
 532                 case UI_BEGIN_FF_ERASE:
 533                         if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
 534                                 retval = -EFAULT;
 535                                 break;
 536                         }
 537                         req = uinput_request_find(udev, ff_erase.request_id);
 538                         if (!(req && req->code == UI_FF_ERASE)) {
 539                                 retval = -EINVAL;
 540                                 break;
 541                         }
 542                         ff_erase.retval = 0;
 543                         ff_erase.effect_id = req->u.effect_id;
 544                         if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
 545                                 retval = -EFAULT;
 546                                 break;
 547                         }
 548                         break;
 549
 550                 case UI_END_FF_UPLOAD:
 551                         if (copy_from_user(&ff_up, p, sizeof(ff_up))) {
 552                                 retval = -EFAULT;
 553                                 break;
 554                         }
 555                         req = uinput_request_find(udev, ff_up.request_id);
 556                         if (!(req && req->code == UI_FF_UPLOAD && req->u.effect)) {
 557                                 retval = -EINVAL;
 558                                 break;
 559                         }
 560                         req->retval = ff_up.retval;
 561                         memcpy(req->u.effect, &ff_up.effect, sizeof(struct ff_effect));
 562                         uinput_request_done(udev, req);
 563                         break;
 564
 565                 case UI_END_FF_ERASE:
 566                         if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
 567                                 retval = -EFAULT;
 568                                 break;
 569                         }
 570                         req = uinput_request_find(udev, ff_erase.request_id);
 571                         if (!(req && req->code == UI_FF_ERASE)) {
 572                                 retval = -EINVAL;
 573                                 break;
 574                         }
 575                         req->retval = ff_erase.retval;
 576                         uinput_request_done(udev, req);
 577                         break;
 578
 579                 default:
 580                         retval = -EINVAL;
 581         }
 582         return retval;
 583 }
 584
 585 static struct file_operations uinput_fops = {
 586         .owner =        THIS_MODULE,
 587         .open =         uinput_open,
 588         .release =      uinput_close,
 589         .read =         uinput_read,
 590         .write =        uinput_write,
 591         .poll =         uinput_poll,
 592         .ioctl =        uinput_ioctl,
 593 };
 594
 595 static struct miscdevice uinput_misc = {
 596         .fops =         &uinput_fops,
 597         .minor =        UINPUT_MINOR,
 598         .name =         UINPUT_NAME,
 599 };
 600
 601 static int __init uinput_init(void)
 602 {
 603         return misc_register(&uinput_misc);
 604 }
 605
 606 static void __exit uinput_exit(void)
 607 {
 608         misc_deregister(&uinput_misc);
 609 }
 610
 611 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
 612 MODULE_DESCRIPTION("User level driver support for input subsystem");
 613 MODULE_LICENSE("GPL");
 614
 615 module_init(uinput_init);
 616 module_exit(uinput_exit);
 617