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