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  *      0.4     01/09/2014 (Benjamin Tissoires <benjamin.tissoires@redhat.com>)
  24  *              - add UI_GET_SYSNAME ioctl
  25  *      0.3     09/04/2006 (Anssi Hannula <anssi.hannula@gmail.com>)
  26  *              - updated ff support for the changes in kernel interface
  27  *              - added MODULE_VERSION
  28  *      0.2     16/10/2004 (Micah Dowty <micah@navi.cx>)
  29  *              - added force feedback support
  30  *              - added UI_SET_PHYS
  31  *      0.1     20/06/2002
  32  *              - first public version
  33  */
  34 #include <linux/poll.h>
  35 #include <linux/sched.h>
  36 #include <linux/slab.h>
  37 #include <linux/module.h>
  38 #include <linux/init.h>
  39 #include <linux/fs.h>
  40 #include <linux/miscdevice.h>
  41 #include <linux/uinput.h>
  42 #include <linux/input/mt.h>
  43 #include "../input-compat.h"
  44
  45 static int uinput_dev_event(struct input_dev *dev,
  46                             unsigned int type, unsigned int code, int value)
  47 {
  48         struct uinput_device    *udev = input_get_drvdata(dev);
  49
  50         udev->buff[udev->head].type = type;
  51         udev->buff[udev->head].code = code;
  52         udev->buff[udev->head].value = value;
  53         do_gettimeofday(&udev->buff[udev->head].time);
  54         udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;
  55
  56         wake_up_interruptible(&udev->waitq);
  57
  58         return 0;
  59 }
  60
  61 /* Atomically allocate an ID for the given request. Returns 0 on success. */
  62 static bool uinput_request_alloc_id(struct uinput_device *udev,
  63                                     struct uinput_request *request)
  64 {
  65         unsigned int id;
  66         bool reserved = false;
  67
  68         spin_lock(&udev->requests_lock);
  69
  70         for (id = 0; id < UINPUT_NUM_REQUESTS; id++) {
  71                 if (!udev->requests[id]) {
  72                         request->id = id;
  73                         udev->requests[id] = request;
  74                         reserved = true;
  75                         break;
  76                 }
  77         }
  78
  79         spin_unlock(&udev->requests_lock);
  80         return reserved;
  81 }
  82
  83 static struct uinput_request *uinput_request_find(struct uinput_device *udev,
  84                                                   unsigned int id)
  85 {
  86         /* Find an input request, by ID. Returns NULL if the ID isn't valid. */
  87         if (id >= UINPUT_NUM_REQUESTS)
  88                 return NULL;
  89
  90         return udev->requests[id];
  91 }
  92
  93 static int uinput_request_reserve_slot(struct uinput_device *udev,
  94                                        struct uinput_request *request)
  95 {
  96         /* Allocate slot. If none are available right away, wait. */
  97         return wait_event_interruptible(udev->requests_waitq,
  98                                         uinput_request_alloc_id(udev, request));
  99 }
 100
 101 static void uinput_request_done(struct uinput_device *udev,
 102                                 struct uinput_request *request)
 103 {
 104         /* Mark slot as available */
 105         udev->requests[request->id] = NULL;
 106         wake_up(&udev->requests_waitq);
 107
 108         complete(&request->done);
 109 }
 110
 111 static int uinput_request_send(struct uinput_device *udev,
 112                                struct uinput_request *request)
 113 {
 114         int retval;
 115
 116         retval = mutex_lock_interruptible(&udev->mutex);
 117         if (retval)
 118                 return retval;
 119
 120         if (udev->state != UIST_CREATED) {
 121                 retval = -ENODEV;
 122                 goto out;
 123         }
 124
 125         init_completion(&request->done);
 126
 127         /*
 128          * Tell our userspace application about this new request
 129          * by queueing an input event.
 130          */
 131         uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id);
 132
 133  out:
 134         mutex_unlock(&udev->mutex);
 135         return retval;
 136 }
 137
 138 static int uinput_request_submit(struct uinput_device *udev,
 139                                  struct uinput_request *request)
 140 {
 141         int error;
 142
 143         error = uinput_request_reserve_slot(udev, request);
 144         if (error)
 145                 return error;
 146
 147         error = uinput_request_send(udev, request);
 148         if (error) {
 149                 uinput_request_done(udev, request);
 150                 return error;
 151         }
 152
 153         wait_for_completion(&request->done);
 154         return request->retval;
 155 }
 156
 157 /*
 158  * Fail all outstanding requests so handlers don't wait for the userspace
 159  * to finish processing them.
 160  */
 161 static void uinput_flush_requests(struct uinput_device *udev)
 162 {
 163         struct uinput_request *request;
 164         int i;
 165
 166         spin_lock(&udev->requests_lock);
 167
 168         for (i = 0; i < UINPUT_NUM_REQUESTS; i++) {
 169                 request = udev->requests[i];
 170                 if (request) {
 171                         request->retval = -ENODEV;
 172                         uinput_request_done(udev, request);
 173                 }
 174         }
 175
 176         spin_unlock(&udev->requests_lock);
 177 }
 178
 179 static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
 180 {
 181         uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
 182 }
 183
 184 static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
 185 {
 186         uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
 187 }
 188
 189 static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value)
 190 {
 191         return uinput_dev_event(dev, EV_FF, effect_id, value);
 192 }
 193
 194 static int uinput_dev_upload_effect(struct input_dev *dev,
 195                                     struct ff_effect *effect,
 196                                     struct ff_effect *old)
 197 {
 198         struct uinput_device *udev = input_get_drvdata(dev);
 199         struct uinput_request request;
 200
 201         /*
 202          * uinput driver does not currently support periodic effects with
 203          * custom waveform since it does not have a way to pass buffer of
 204          * samples (custom_data) to userspace. If ever there is a device
 205          * supporting custom waveforms we would need to define an additional
 206          * ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out.
 207          */
 208         if (effect->type == FF_PERIODIC &&
 209                         effect->u.periodic.waveform == FF_CUSTOM)
 210                 return -EINVAL;
 211
 212         request.code = UI_FF_UPLOAD;
 213         request.u.upload.effect = effect;
 214         request.u.upload.old = old;
 215
 216         return uinput_request_submit(udev, &request);
 217 }
 218
 219 static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
 220 {
 221         struct uinput_device *udev = input_get_drvdata(dev);
 222         struct uinput_request request;
 223
 224         if (!test_bit(EV_FF, dev->evbit))
 225                 return -ENOSYS;
 226
 227         request.code = UI_FF_ERASE;
 228         request.u.effect_id = effect_id;
 229
 230         return uinput_request_submit(udev, &request);
 231 }
 232
 233 static void uinput_destroy_device(struct uinput_device *udev)
 234 {
 235         const char *name, *phys;
 236         struct input_dev *dev = udev->dev;
 237         enum uinput_state old_state = udev->state;
 238
 239         udev->state = UIST_NEW_DEVICE;
 240
 241         if (dev) {
 242                 name = dev->name;
 243                 phys = dev->phys;
 244                 if (old_state == UIST_CREATED) {
 245                         uinput_flush_requests(udev);
 246                         input_unregister_device(dev);
 247                 } else {
 248                         input_free_device(dev);
 249                 }
 250                 kfree(name);
 251                 kfree(phys);
 252                 udev->dev = NULL;
 253         }
 254 }
 255
 256 static int uinput_create_device(struct uinput_device *udev)
 257 {
 258         struct input_dev *dev = udev->dev;
 259         int error, nslot;
 260
 261         if (udev->state != UIST_SETUP_COMPLETE) {
 262                 printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
 263                 return -EINVAL;
 264         }
 265
 266         if (test_bit(ABS_MT_SLOT, dev->absbit)) {
 267                 nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1;
 268                 error = input_mt_init_slots(dev, nslot, 0);
 269                 if (error)
 270                         goto fail1;
 271         } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
 272                 input_set_events_per_packet(dev, 60);
 273         }
 274
 275         if (udev->ff_effects_max) {
 276                 error = input_ff_create(dev, udev->ff_effects_max);
 277                 if (error)
 278                         goto fail1;
 279
 280                 dev->ff->upload = uinput_dev_upload_effect;
 281                 dev->ff->erase = uinput_dev_erase_effect;
 282                 dev->ff->playback = uinput_dev_playback;
 283                 dev->ff->set_gain = uinput_dev_set_gain;
 284                 dev->ff->set_autocenter = uinput_dev_set_autocenter;
 285         }
 286
 287         error = input_register_device(udev->dev);
 288         if (error)
 289                 goto fail2;
 290
 291         udev->state = UIST_CREATED;
 292
 293         return 0;
 294
 295  fail2: input_ff_destroy(dev);
 296  fail1: uinput_destroy_device(udev);
 297         return error;
 298 }
 299
 300 static int uinput_open(struct inode *inode, struct file *file)
 301 {
 302         struct uinput_device *newdev;
 303
 304         newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
 305         if (!newdev)
 306                 return -ENOMEM;
 307
 308         mutex_init(&newdev->mutex);
 309         spin_lock_init(&newdev->requests_lock);
 310         init_waitqueue_head(&newdev->requests_waitq);
 311         init_waitqueue_head(&newdev->waitq);
 312         newdev->state = UIST_NEW_DEVICE;
 313
 314         file->private_data = newdev;
 315         nonseekable_open(inode, file);
 316
 317         return 0;
 318 }
 319
 320 static int uinput_validate_absinfo(struct input_dev *dev, unsigned int code,
 321                                    const struct input_absinfo *abs)
 322 {
 323         int min, max;
 324
 325         min = abs->minimum;
 326         max = abs->maximum;
 327
 328         if ((min != 0 || max != 0) && max <= min) {
 329                 printk(KERN_DEBUG
 330                        "%s: invalid abs[%02x] min:%d max:%d\n",
 331                        UINPUT_NAME, code, min, max);
 332                 return -EINVAL;
 333         }
 334
 335         if (abs->flat > max - min) {
 336                 printk(KERN_DEBUG
 337                        "%s: abs_flat #%02x out of range: %d (min:%d/max:%d)\n",
 338                        UINPUT_NAME, code, abs->flat, min, max);
 339                 return -EINVAL;
 340         }
 341
 342         return 0;
 343 }
 344
 345 static int uinput_validate_absbits(struct input_dev *dev)
 346 {
 347         unsigned int cnt;
 348         int error;
 349
 350         if (!test_bit(EV_ABS, dev->evbit))
 351                 return 0;
 352
 353         /*
 354          * Check if absmin/absmax/absfuzz/absflat are sane.
 355          */
 356
 357         for_each_set_bit(cnt, dev->absbit, ABS_CNT) {
 358                 if (!dev->absinfo)
 359                         return -EINVAL;
 360
 361                 error = uinput_validate_absinfo(dev, cnt, &dev->absinfo[cnt]);
 362                 if (error)
 363                         return error;
 364         }
 365
 366         return 0;
 367 }
 368
 369 static int uinput_allocate_device(struct uinput_device *udev)
 370 {
 371         udev->dev = input_allocate_device();
 372         if (!udev->dev)
 373                 return -ENOMEM;
 374
 375         udev->dev->event = uinput_dev_event;
 376         input_set_drvdata(udev->dev, udev);
 377
 378         return 0;
 379 }
 380
 381 static int uinput_dev_setup(struct uinput_device *udev,
 382                             struct uinput_setup __user *arg)
 383 {
 384         struct uinput_setup setup;
 385         struct input_dev *dev;
 386
 387         if (udev->state == UIST_CREATED)
 388                 return -EINVAL;
 389
 390         if (copy_from_user(&setup, arg, sizeof(setup)))
 391                 return -EFAULT;
 392
 393         if (!setup.name[0])
 394                 return -EINVAL;
 395
 396         dev = udev->dev;
 397         dev->id = setup.id;
 398         udev->ff_effects_max = setup.ff_effects_max;
 399
 400         kfree(dev->name);
 401         dev->name = kstrndup(setup.name, UINPUT_MAX_NAME_SIZE, GFP_KERNEL);
 402         if (!dev->name)
 403                 return -ENOMEM;
 404
 405         udev->state = UIST_SETUP_COMPLETE;
 406         return 0;
 407 }
 408
 409 static int uinput_abs_setup(struct uinput_device *udev,
 410                             struct uinput_setup __user *arg, size_t size)
 411 {
 412         struct uinput_abs_setup setup = {};
 413         struct input_dev *dev;
 414         int error;
 415
 416         if (size > sizeof(setup))
 417                 return -E2BIG;
 418
 419         if (udev->state == UIST_CREATED)
 420                 return -EINVAL;
 421
 422         if (copy_from_user(&setup, arg, size))
 423                 return -EFAULT;
 424
 425         if (setup.code > ABS_MAX)
 426                 return -ERANGE;
 427
 428         dev = udev->dev;
 429
 430         error = uinput_validate_absinfo(dev, setup.code, &setup.absinfo);
 431         if (error)
 432                 return error;
 433
 434         input_alloc_absinfo(dev);
 435         if (!dev->absinfo)
 436                 return -ENOMEM;
 437
 438         set_bit(setup.code, dev->absbit);
 439         dev->absinfo[setup.code] = setup.absinfo;
 440         return 0;
 441 }
 442
 443 /* legacy setup via write() */
 444 static int uinput_setup_device_legacy(struct uinput_device *udev,
 445                                       const char __user *buffer, size_t count)
 446 {
 447         struct uinput_user_dev  *user_dev;
 448         struct input_dev        *dev;
 449         int                     i;
 450         int                     retval;
 451
 452         if (count != sizeof(struct uinput_user_dev))
 453                 return -EINVAL;
 454
 455         if (!udev->dev) {
 456                 retval = uinput_allocate_device(udev);
 457                 if (retval)
 458                         return retval;
 459         }
 460
 461         dev = udev->dev;
 462
 463         user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev));
 464         if (IS_ERR(user_dev))
 465                 return PTR_ERR(user_dev);
 466
 467         udev->ff_effects_max = user_dev->ff_effects_max;
 468
 469         /* Ensure name is filled in */
 470         if (!user_dev->name[0]) {
 471                 retval = -EINVAL;
 472                 goto exit;
 473         }
 474
 475         kfree(dev->name);
 476         dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE,
 477                              GFP_KERNEL);
 478         if (!dev->name) {
 479                 retval = -ENOMEM;
 480                 goto exit;
 481         }
 482
 483         dev->id.bustype = user_dev->id.bustype;
 484         dev->id.vendor  = user_dev->id.vendor;
 485         dev->id.product = user_dev->id.product;
 486         dev->id.version = user_dev->id.version;
 487
 488         for (i = 0; i < ABS_CNT; i++) {
 489                 input_abs_set_max(dev, i, user_dev->absmax[i]);
 490                 input_abs_set_min(dev, i, user_dev->absmin[i]);
 491                 input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]);
 492                 input_abs_set_flat(dev, i, user_dev->absflat[i]);
 493         }
 494
 495         retval = uinput_validate_absbits(dev);
 496         if (retval < 0)
 497                 goto exit;
 498
 499         udev->state = UIST_SETUP_COMPLETE;
 500         retval = count;
 501
 502  exit:
 503         kfree(user_dev);
 504         return retval;
 505 }
 506
 507 static ssize_t uinput_inject_events(struct uinput_device *udev,
 508                                     const char __user *buffer, size_t count)
 509 {
 510         struct input_event ev;
 511         size_t bytes = 0;
 512
 513         if (count != 0 && count < input_event_size())
 514                 return -EINVAL;
 515
 516         while (bytes + input_event_size() <= count) {
 517                 /*
 518                  * Note that even if some events were fetched successfully
 519                  * we are still going to return EFAULT instead of partial
 520                  * count to let userspace know that it got it's buffers
 521                  * all wrong.
 522                  */
 523                 if (input_event_from_user(buffer + bytes, &ev))
 524                         return -EFAULT;
 525
 526                 input_event(udev->dev, ev.type, ev.code, ev.value);
 527                 bytes += input_event_size();
 528         }
 529
 530         return bytes;
 531 }
 532
 533 static ssize_t uinput_write(struct file *file, const char __user *buffer,
 534                             size_t count, loff_t *ppos)
 535 {
 536         struct uinput_device *udev = file->private_data;
 537         int retval;
 538
 539         if (count == 0)
 540                 return 0;
 541
 542         retval = mutex_lock_interruptible(&udev->mutex);
 543         if (retval)
 544                 return retval;
 545
 546         retval = udev->state == UIST_CREATED ?
 547                         uinput_inject_events(udev, buffer, count) :
 548                         uinput_setup_device_legacy(udev, buffer, count);
 549
 550         mutex_unlock(&udev->mutex);
 551
 552         return retval;
 553 }
 554
 555 static bool uinput_fetch_next_event(struct uinput_device *udev,
 556                                     struct input_event *event)
 557 {
 558         bool have_event;
 559
 560         spin_lock_irq(&udev->dev->event_lock);
 561
 562         have_event = udev->head != udev->tail;
 563         if (have_event) {
 564                 *event = udev->buff[udev->tail];
 565                 udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
 566         }
 567
 568         spin_unlock_irq(&udev->dev->event_lock);
 569
 570         return have_event;
 571 }
 572
 573 static ssize_t uinput_events_to_user(struct uinput_device *udev,
 574                                      char __user *buffer, size_t count)
 575 {
 576         struct input_event event;
 577         size_t read = 0;
 578
 579         while (read + input_event_size() <= count &&
 580                uinput_fetch_next_event(udev, &event)) {
 581
 582                 if (input_event_to_user(buffer + read, &event))
 583                         return -EFAULT;
 584
 585                 read += input_event_size();
 586         }
 587
 588         return read;
 589 }
 590
 591 static ssize_t uinput_read(struct file *file, char __user *buffer,
 592                            size_t count, loff_t *ppos)
 593 {
 594         struct uinput_device *udev = file->private_data;
 595         ssize_t retval;
 596
 597         if (count != 0 && count < input_event_size())
 598                 return -EINVAL;
 599
 600         do {
 601                 retval = mutex_lock_interruptible(&udev->mutex);
 602                 if (retval)
 603                         return retval;
 604
 605                 if (udev->state != UIST_CREATED)
 606                         retval = -ENODEV;
 607                 else if (udev->head == udev->tail &&
 608                          (file->f_flags & O_NONBLOCK))
 609                         retval = -EAGAIN;
 610                 else
 611                         retval = uinput_events_to_user(udev, buffer, count);
 612
 613                 mutex_unlock(&udev->mutex);
 614
 615                 if (retval || count == 0)
 616                         break;
 617
 618                 if (!(file->f_flags & O_NONBLOCK))
 619                         retval = wait_event_interruptible(udev->waitq,
 620                                                   udev->head != udev->tail ||
 621                                                   udev->state != UIST_CREATED);
 622         } while (retval == 0);
 623
 624         return retval;
 625 }
 626
 627 static unsigned int uinput_poll(struct file *file, poll_table *wait)
 628 {
 629         struct uinput_device *udev = file->private_data;
 630
 631         poll_wait(file, &udev->waitq, wait);
 632
 633         if (udev->head != udev->tail)
 634                 return POLLIN | POLLRDNORM;
 635
 636         return 0;
 637 }
 638
 639 static int uinput_release(struct inode *inode, struct file *file)
 640 {
 641         struct uinput_device *udev = file->private_data;
 642
 643         uinput_destroy_device(udev);
 644         kfree(udev);
 645
 646         return 0;
 647 }
 648
 649 #ifdef CONFIG_COMPAT
 650 struct uinput_ff_upload_compat {
 651         __u32                   request_id;
 652         __s32                   retval;
 653         struct ff_effect_compat effect;
 654         struct ff_effect_compat old;
 655 };
 656
 657 static int uinput_ff_upload_to_user(char __user *buffer,
 658                                     const struct uinput_ff_upload *ff_up)
 659 {
 660         if (INPUT_COMPAT_TEST) {
 661                 struct uinput_ff_upload_compat ff_up_compat;
 662
 663                 ff_up_compat.request_id = ff_up->request_id;
 664                 ff_up_compat.retval = ff_up->retval;
 665                 /*
 666                  * It so happens that the pointer that gives us the trouble
 667                  * is the last field in the structure. Since we don't support
 668                  * custom waveforms in uinput anyway we can just copy the whole
 669                  * thing (to the compat size) and ignore the pointer.
 670                  */
 671                 memcpy(&ff_up_compat.effect, &ff_up->effect,
 672                         sizeof(struct ff_effect_compat));
 673                 memcpy(&ff_up_compat.old, &ff_up->old,
 674                         sizeof(struct ff_effect_compat));
 675
 676                 if (copy_to_user(buffer, &ff_up_compat,
 677                                  sizeof(struct uinput_ff_upload_compat)))
 678                         return -EFAULT;
 679         } else {
 680                 if (copy_to_user(buffer, ff_up,
 681                                  sizeof(struct uinput_ff_upload)))
 682                         return -EFAULT;
 683         }
 684
 685         return 0;
 686 }
 687
 688 static int uinput_ff_upload_from_user(const char __user *buffer,
 689                                       struct uinput_ff_upload *ff_up)
 690 {
 691         if (INPUT_COMPAT_TEST) {
 692                 struct uinput_ff_upload_compat ff_up_compat;
 693
 694                 if (copy_from_user(&ff_up_compat, buffer,
 695                                    sizeof(struct uinput_ff_upload_compat)))
 696                         return -EFAULT;
 697
 698                 ff_up->request_id = ff_up_compat.request_id;
 699                 ff_up->retval = ff_up_compat.retval;
 700                 memcpy(&ff_up->effect, &ff_up_compat.effect,
 701                         sizeof(struct ff_effect_compat));
 702                 memcpy(&ff_up->old, &ff_up_compat.old,
 703                         sizeof(struct ff_effect_compat));
 704
 705         } else {
 706                 if (copy_from_user(ff_up, buffer,
 707                                    sizeof(struct uinput_ff_upload)))
 708                         return -EFAULT;
 709         }
 710
 711         return 0;
 712 }
 713
 714 #else
 715
 716 static int uinput_ff_upload_to_user(char __user *buffer,
 717                                     const struct uinput_ff_upload *ff_up)
 718 {
 719         if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
 720                 return -EFAULT;
 721
 722         return 0;
 723 }
 724
 725 static int uinput_ff_upload_from_user(const char __user *buffer,
 726                                       struct uinput_ff_upload *ff_up)
 727 {
 728         if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
 729                 return -EFAULT;
 730
 731         return 0;
 732 }
 733
 734 #endif
 735
 736 #define uinput_set_bit(_arg, _bit, _max)                \
 737 ({                                                      \
 738         int __ret = 0;                                  \
 739         if (udev->state == UIST_CREATED)                \
 740                 __ret =  -EINVAL;                       \
 741         else if ((_arg) > (_max))                       \
 742                 __ret = -EINVAL;                        \
 743         else set_bit((_arg), udev->dev->_bit);          \
 744         __ret;                                          \
 745 })
 746
 747 static int uinput_str_to_user(void __user *dest, const char *str,
 748                               unsigned int maxlen)
 749 {
 750         char __user *p = dest;
 751         int len, ret;
 752
 753         if (!str)
 754                 return -ENOENT;
 755
 756         if (maxlen == 0)
 757                 return -EINVAL;
 758
 759         len = strlen(str) + 1;
 760         if (len > maxlen)
 761                 len = maxlen;
 762
 763         ret = copy_to_user(p, str, len);
 764         if (ret)
 765                 return -EFAULT;
 766
 767         /* force terminating '\0' */
 768         ret = put_user(0, p + len - 1);
 769         return ret ? -EFAULT : len;
 770 }
 771
 772 static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
 773                                  unsigned long arg, void __user *p)
 774 {
 775         int                     retval;
 776         struct uinput_device    *udev = file->private_data;
 777         struct uinput_ff_upload ff_up;
 778         struct uinput_ff_erase  ff_erase;
 779         struct uinput_request   *req;
 780         char                    *phys;
 781         const char              *name;
 782         unsigned int            size;
 783
 784         retval = mutex_lock_interruptible(&udev->mutex);
 785         if (retval)
 786                 return retval;
 787
 788         if (!udev->dev) {
 789                 retval = uinput_allocate_device(udev);
 790                 if (retval)
 791                         goto out;
 792         }
 793
 794         switch (cmd) {
 795                 case UI_GET_VERSION:
 796                         if (put_user(UINPUT_VERSION,
 797                                      (unsigned int __user *)p))
 798                                 retval = -EFAULT;
 799                         goto out;
 800
 801                 case UI_DEV_CREATE:
 802                         retval = uinput_create_device(udev);
 803                         goto out;
 804
 805                 case UI_DEV_DESTROY:
 806                         uinput_destroy_device(udev);
 807                         goto out;
 808
 809                 case UI_DEV_SETUP:
 810                         retval = uinput_dev_setup(udev, p);
 811                         goto out;
 812
 813                 /* UI_ABS_SETUP is handled in the variable size ioctls */
 814
 815                 case UI_SET_EVBIT:
 816                         retval = uinput_set_bit(arg, evbit, EV_MAX);
 817                         goto out;
 818
 819                 case UI_SET_KEYBIT:
 820                         retval = uinput_set_bit(arg, keybit, KEY_MAX);
 821                         goto out;
 822
 823                 case UI_SET_RELBIT:
 824                         retval = uinput_set_bit(arg, relbit, REL_MAX);
 825                         goto out;
 826
 827                 case UI_SET_ABSBIT:
 828                         retval = uinput_set_bit(arg, absbit, ABS_MAX);
 829                         goto out;
 830
 831                 case UI_SET_MSCBIT:
 832                         retval = uinput_set_bit(arg, mscbit, MSC_MAX);
 833                         goto out;
 834
 835                 case UI_SET_LEDBIT:
 836                         retval = uinput_set_bit(arg, ledbit, LED_MAX);
 837                         goto out;
 838
 839                 case UI_SET_SNDBIT:
 840                         retval = uinput_set_bit(arg, sndbit, SND_MAX);
 841                         goto out;
 842
 843                 case UI_SET_FFBIT:
 844                         retval = uinput_set_bit(arg, ffbit, FF_MAX);
 845                         goto out;
 846
 847                 case UI_SET_SWBIT:
 848                         retval = uinput_set_bit(arg, swbit, SW_MAX);
 849                         goto out;
 850
 851                 case UI_SET_PROPBIT:
 852                         retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
 853                         goto out;
 854
 855                 case UI_SET_PHYS:
 856                         if (udev->state == UIST_CREATED) {
 857                                 retval = -EINVAL;
 858                                 goto out;
 859                         }
 860
 861                         phys = strndup_user(p, 1024);
 862                         if (IS_ERR(phys)) {
 863                                 retval = PTR_ERR(phys);
 864                                 goto out;
 865                         }
 866
 867                         kfree(udev->dev->phys);
 868                         udev->dev->phys = phys;
 869                         goto out;
 870
 871                 case UI_BEGIN_FF_UPLOAD:
 872                         retval = uinput_ff_upload_from_user(p, &ff_up);
 873                         if (retval)
 874                                 goto out;
 875
 876                         req = uinput_request_find(udev, ff_up.request_id);
 877                         if (!req || req->code != UI_FF_UPLOAD ||
 878                             !req->u.upload.effect) {
 879                                 retval = -EINVAL;
 880                                 goto out;
 881                         }
 882
 883                         ff_up.retval = 0;
 884                         ff_up.effect = *req->u.upload.effect;
 885                         if (req->u.upload.old)
 886                                 ff_up.old = *req->u.upload.old;
 887                         else
 888                                 memset(&ff_up.old, 0, sizeof(struct ff_effect));
 889
 890                         retval = uinput_ff_upload_to_user(p, &ff_up);
 891                         goto out;
 892
 893                 case UI_BEGIN_FF_ERASE:
 894                         if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
 895                                 retval = -EFAULT;
 896                                 goto out;
 897                         }
 898
 899                         req = uinput_request_find(udev, ff_erase.request_id);
 900                         if (!req || req->code != UI_FF_ERASE) {
 901                                 retval = -EINVAL;
 902                                 goto out;
 903                         }
 904
 905                         ff_erase.retval = 0;
 906                         ff_erase.effect_id = req->u.effect_id;
 907                         if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
 908                                 retval = -EFAULT;
 909                                 goto out;
 910                         }
 911
 912                         goto out;
 913
 914                 case UI_END_FF_UPLOAD:
 915                         retval = uinput_ff_upload_from_user(p, &ff_up);
 916                         if (retval)
 917                                 goto out;
 918
 919                         req = uinput_request_find(udev, ff_up.request_id);
 920                         if (!req || req->code != UI_FF_UPLOAD ||
 921                             !req->u.upload.effect) {
 922                                 retval = -EINVAL;
 923                                 goto out;
 924                         }
 925
 926                         req->retval = ff_up.retval;
 927                         uinput_request_done(udev, req);
 928                         goto out;
 929
 930                 case UI_END_FF_ERASE:
 931                         if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
 932                                 retval = -EFAULT;
 933                                 goto out;
 934                         }
 935
 936                         req = uinput_request_find(udev, ff_erase.request_id);
 937                         if (!req || req->code != UI_FF_ERASE) {
 938                                 retval = -EINVAL;
 939                                 goto out;
 940                         }
 941
 942                         req->retval = ff_erase.retval;
 943                         uinput_request_done(udev, req);
 944                         goto out;
 945         }
 946
 947         size = _IOC_SIZE(cmd);
 948
 949         /* Now check variable-length commands */
 950         switch (cmd & ~IOCSIZE_MASK) {
 951         case UI_GET_SYSNAME(0):
 952                 if (udev->state != UIST_CREATED) {
 953                         retval = -ENOENT;
 954                         goto out;
 955                 }
 956                 name = dev_name(&udev->dev->dev);
 957                 retval = uinput_str_to_user(p, name, size);
 958                 goto out;
 959
 960         case UI_ABS_SETUP & ~IOCSIZE_MASK:
 961                 retval = uinput_abs_setup(udev, p, size);
 962                 goto out;
 963         }
 964
 965         retval = -EINVAL;
 966  out:
 967         mutex_unlock(&udev->mutex);
 968         return retval;
 969 }
 970
 971 static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 972 {
 973         return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
 974 }
 975
 976 #ifdef CONFIG_COMPAT
 977 static long uinput_compat_ioctl(struct file *file,
 978                                 unsigned int cmd, unsigned long arg)
 979 {
 980         return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
 981 }
 982 #endif
 983
 984 static const struct file_operations uinput_fops = {
 985         .owner          = THIS_MODULE,
 986         .open           = uinput_open,
 987         .release        = uinput_release,
 988         .read           = uinput_read,
 989         .write          = uinput_write,
 990         .poll           = uinput_poll,
 991         .unlocked_ioctl = uinput_ioctl,
 992 #ifdef CONFIG_COMPAT
 993         .compat_ioctl   = uinput_compat_ioctl,
 994 #endif
 995         .llseek         = no_llseek,
 996 };
 997
 998 static struct miscdevice uinput_misc = {
 999         .fops           = &uinput_fops,
1000         .minor          = UINPUT_MINOR,
1001         .name           = UINPUT_NAME,
1002 };
1003 MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
1004 MODULE_ALIAS("devname:" UINPUT_NAME);
1005
1006 static int __init uinput_init(void)
1007 {
1008         return misc_register(&uinput_misc);
1009 }
1010
1011 static void __exit uinput_exit(void)
1012 {
1013         misc_deregister(&uinput_misc);
1014 }
1015
1016 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
1017 MODULE_DESCRIPTION("User level driver support for input subsystem");
1018 MODULE_LICENSE("GPL");
1019 MODULE_VERSION("0.3");
1020
1021 module_init(uinput_init);
1022 module_exit(uinput_exit);