drivers/media/video/uvc/uvc_v4l2.c

   1 /*
   2  *      uvc_v4l2.c  --  USB Video Class driver - V4L2 API
   3  *
   4  *      Copyright (C) 2005-2010
   5  *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
   6  *
   7  *      This program is free software; you can redistribute it and/or modify
   8  *      it under the terms of the GNU General Public License as published by
   9  *      the Free Software Foundation; either version 2 of the License, or
  10  *      (at your option) any later version.
  11  *
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/version.h>
  16 #include <linux/list.h>
  17 #include <linux/module.h>
  18 #include <linux/slab.h>
  19 #include <linux/usb.h>
  20 #include <linux/videodev2.h>
  21 #include <linux/vmalloc.h>
  22 #include <linux/mm.h>
  23 #include <linux/wait.h>
  24 #include <asm/atomic.h>
  25
  26 #include <media/v4l2-common.h>
  27 #include <media/v4l2-ioctl.h>
  28
  29 #include "uvcvideo.h"
  30
  31 /* ------------------------------------------------------------------------
  32  * UVC ioctls
  33  */
  34 static int uvc_ioctl_ctrl_map(struct uvc_video_chain *chain,
  35         struct uvc_xu_control_mapping *xmap, int old)
  36 {
  37         struct uvc_control_mapping *map;
  38         unsigned int size;
  39         int ret;
  40
  41         map = kzalloc(sizeof *map, GFP_KERNEL);
  42         if (map == NULL)
  43                 return -ENOMEM;
  44
  45         map->id = xmap->id;
  46         memcpy(map->name, xmap->name, sizeof map->name);
  47         memcpy(map->entity, xmap->entity, sizeof map->entity);
  48         map->selector = xmap->selector;
  49         map->size = xmap->size;
  50         map->offset = xmap->offset;
  51         map->v4l2_type = xmap->v4l2_type;
  52         map->data_type = xmap->data_type;
  53
  54         switch (xmap->v4l2_type) {
  55         case V4L2_CTRL_TYPE_INTEGER:
  56         case V4L2_CTRL_TYPE_BOOLEAN:
  57         case V4L2_CTRL_TYPE_BUTTON:
  58                 break;
  59
  60         case V4L2_CTRL_TYPE_MENU:
  61                 if (old) {
  62                         uvc_trace(UVC_TRACE_CONTROL, "V4L2_CTRL_TYPE_MENU not "
  63                                   "supported for UVCIOC_CTRL_MAP_OLD.\n");
  64                         ret = -EINVAL;
  65                         goto done;
  66                 }
  67
  68                 /* Prevent excessive memory consumption, as well as integer
  69                  * overflows.
  70                  */
  71                 if (xmap->menu_count == 0 ||
  72                     xmap->menu_count > UVC_MAX_CONTROL_MENU_ENTRIES) {
  73                         ret = -EINVAL;
  74                         goto done;
  75                 }
  76
  77                 size = xmap->menu_count * sizeof(*map->menu_info);
  78                 map->menu_info = kmalloc(size, GFP_KERNEL);
  79                 if (map->menu_info == NULL) {
  80                         ret = -ENOMEM;
  81                         goto done;
  82                 }
  83
  84                 if (copy_from_user(map->menu_info, xmap->menu_info, size)) {
  85                         ret = -EFAULT;
  86                         goto done;
  87                 }
  88
  89                 map->menu_count = xmap->menu_count;
  90                 break;
  91
  92         default:
  93                 uvc_trace(UVC_TRACE_CONTROL, "Unsupported V4L2 control type "
  94                           "%u.\n", xmap->v4l2_type);
  95                 ret = -EINVAL;
  96                 goto done;
  97         }
  98
  99         ret = uvc_ctrl_add_mapping(chain, map);
 100
 101 done:
 102         kfree(map->menu_info);
 103         kfree(map);
 104
 105         return ret;
 106 }
 107
 108 /* ------------------------------------------------------------------------
 109  * V4L2 interface
 110  */
 111
 112 /*
 113  * Find the frame interval closest to the requested frame interval for the
 114  * given frame format and size. This should be done by the device as part of
 115  * the Video Probe and Commit negotiation, but some hardware don't implement
 116  * that feature.
 117  */
 118 static __u32 uvc_try_frame_interval(struct uvc_frame *frame, __u32 interval)
 119 {
 120         unsigned int i;
 121
 122         if (frame->bFrameIntervalType) {
 123                 __u32 best = -1, dist;
 124
 125                 for (i = 0; i < frame->bFrameIntervalType; ++i) {
 126                         dist = interval > frame->dwFrameInterval[i]
 127                              ? interval - frame->dwFrameInterval[i]
 128                              : frame->dwFrameInterval[i] - interval;
 129
 130                         if (dist > best)
 131                                 break;
 132
 133                         best = dist;
 134                 }
 135
 136                 interval = frame->dwFrameInterval[i-1];
 137         } else {
 138                 const __u32 min = frame->dwFrameInterval[0];
 139                 const __u32 max = frame->dwFrameInterval[1];
 140                 const __u32 step = frame->dwFrameInterval[2];
 141
 142                 interval = min + (interval - min + step/2) / step * step;
 143                 if (interval > max)
 144                         interval = max;
 145         }
 146
 147         return interval;
 148 }
 149
 150 static int uvc_v4l2_try_format(struct uvc_streaming *stream,
 151         struct v4l2_format *fmt, struct uvc_streaming_control *probe,
 152         struct uvc_format **uvc_format, struct uvc_frame **uvc_frame)
 153 {
 154         struct uvc_format *format = NULL;
 155         struct uvc_frame *frame = NULL;
 156         __u16 rw, rh;
 157         unsigned int d, maxd;
 158         unsigned int i;
 159         __u32 interval;
 160         int ret = 0;
 161         __u8 *fcc;
 162
 163         if (fmt->type != stream->type)
 164                 return -EINVAL;
 165
 166         fcc = (__u8 *)&fmt->fmt.pix.pixelformat;
 167         uvc_trace(UVC_TRACE_FORMAT, "Trying format 0x%08x (%c%c%c%c): %ux%u.\n",
 168                         fmt->fmt.pix.pixelformat,
 169                         fcc[0], fcc[1], fcc[2], fcc[3],
 170                         fmt->fmt.pix.width, fmt->fmt.pix.height);
 171
 172         /* Check if the hardware supports the requested format. */
 173         for (i = 0; i < stream->nformats; ++i) {
 174                 format = &stream->format[i];
 175                 if (format->fcc == fmt->fmt.pix.pixelformat)
 176                         break;
 177         }
 178
 179         if (format == NULL || format->fcc != fmt->fmt.pix.pixelformat) {
 180                 uvc_trace(UVC_TRACE_FORMAT, "Unsupported format 0x%08x.\n",
 181                                 fmt->fmt.pix.pixelformat);
 182                 return -EINVAL;
 183         }
 184
 185         /* Find the closest image size. The distance between image sizes is
 186          * the size in pixels of the non-overlapping regions between the
 187          * requested size and the frame-specified size.
 188          */
 189         rw = fmt->fmt.pix.width;
 190         rh = fmt->fmt.pix.height;
 191         maxd = (unsigned int)-1;
 192
 193         for (i = 0; i < format->nframes; ++i) {
 194                 __u16 w = format->frame[i].wWidth;
 195                 __u16 h = format->frame[i].wHeight;
 196
 197                 d = min(w, rw) * min(h, rh);
 198                 d = w*h + rw*rh - 2*d;
 199                 if (d < maxd) {
 200                         maxd = d;
 201                         frame = &format->frame[i];
 202                 }
 203
 204                 if (maxd == 0)
 205                         break;
 206         }
 207
 208         if (frame == NULL) {
 209                 uvc_trace(UVC_TRACE_FORMAT, "Unsupported size %ux%u.\n",
 210                                 fmt->fmt.pix.width, fmt->fmt.pix.height);
 211                 return -EINVAL;
 212         }
 213
 214         /* Use the default frame interval. */
 215         interval = frame->dwDefaultFrameInterval;
 216         uvc_trace(UVC_TRACE_FORMAT, "Using default frame interval %u.%u us "
 217                 "(%u.%u fps).\n", interval/10, interval%10, 10000000/interval,
 218                 (100000000/interval)%10);
 219
 220         /* Set the format index, frame index and frame interval. */
 221         memset(probe, 0, sizeof *probe);
 222         probe->bmHint = 1;      /* dwFrameInterval */
 223         probe->bFormatIndex = format->index;
 224         probe->bFrameIndex = frame->bFrameIndex;
 225         probe->dwFrameInterval = uvc_try_frame_interval(frame, interval);
 226         /* Some webcams stall the probe control set request when the
 227          * dwMaxVideoFrameSize field is set to zero. The UVC specification
 228          * clearly states that the field is read-only from the host, so this
 229          * is a webcam bug. Set dwMaxVideoFrameSize to the value reported by
 230          * the webcam to work around the problem.
 231          *
 232          * The workaround could probably be enabled for all webcams, so the
 233          * quirk can be removed if needed. It's currently useful to detect
 234          * webcam bugs and fix them before they hit the market (providing
 235          * developers test their webcams with the Linux driver as well as with
 236          * the Windows driver).
 237          */
 238         mutex_lock(&stream->mutex);
 239         if (stream->dev->quirks & UVC_QUIRK_PROBE_EXTRAFIELDS)
 240                 probe->dwMaxVideoFrameSize =
 241                         stream->ctrl.dwMaxVideoFrameSize;
 242
 243         /* Probe the device. */
 244         ret = uvc_probe_video(stream, probe);
 245         mutex_unlock(&stream->mutex);
 246         if (ret < 0)
 247                 goto done;
 248
 249         fmt->fmt.pix.width = frame->wWidth;
 250         fmt->fmt.pix.height = frame->wHeight;
 251         fmt->fmt.pix.field = V4L2_FIELD_NONE;
 252         fmt->fmt.pix.bytesperline = format->bpp * frame->wWidth / 8;
 253         fmt->fmt.pix.sizeimage = probe->dwMaxVideoFrameSize;
 254         fmt->fmt.pix.colorspace = format->colorspace;
 255         fmt->fmt.pix.priv = 0;
 256
 257         if (uvc_format != NULL)
 258                 *uvc_format = format;
 259         if (uvc_frame != NULL)
 260                 *uvc_frame = frame;
 261
 262 done:
 263         return ret;
 264 }
 265
 266 static int uvc_v4l2_get_format(struct uvc_streaming *stream,
 267         struct v4l2_format *fmt)
 268 {
 269         struct uvc_format *format;
 270         struct uvc_frame *frame;
 271         int ret = 0;
 272
 273         if (fmt->type != stream->type)
 274                 return -EINVAL;
 275
 276         mutex_lock(&stream->mutex);
 277         format = stream->cur_format;
 278         frame = stream->cur_frame;
 279
 280         if (format == NULL || frame == NULL) {
 281                 ret = -EINVAL;
 282                 goto done;
 283         }
 284
 285         fmt->fmt.pix.pixelformat = format->fcc;
 286         fmt->fmt.pix.width = frame->wWidth;
 287         fmt->fmt.pix.height = frame->wHeight;
 288         fmt->fmt.pix.field = V4L2_FIELD_NONE;
 289         fmt->fmt.pix.bytesperline = format->bpp * frame->wWidth / 8;
 290         fmt->fmt.pix.sizeimage = stream->ctrl.dwMaxVideoFrameSize;
 291         fmt->fmt.pix.colorspace = format->colorspace;
 292         fmt->fmt.pix.priv = 0;
 293
 294 done:
 295         mutex_unlock(&stream->mutex);
 296         return ret;
 297 }
 298
 299 static int uvc_v4l2_set_format(struct uvc_streaming *stream,
 300         struct v4l2_format *fmt)
 301 {
 302         struct uvc_streaming_control probe;
 303         struct uvc_format *format;
 304         struct uvc_frame *frame;
 305         int ret;
 306
 307         if (fmt->type != stream->type)
 308                 return -EINVAL;
 309
 310         ret = uvc_v4l2_try_format(stream, fmt, &probe, &format, &frame);
 311         if (ret < 0)
 312                 return ret;
 313
 314         mutex_lock(&stream->mutex);
 315
 316         if (uvc_queue_allocated(&stream->queue)) {
 317                 ret = -EBUSY;
 318                 goto done;
 319         }
 320
 321         memcpy(&stream->ctrl, &probe, sizeof probe);
 322         stream->cur_format = format;
 323         stream->cur_frame = frame;
 324
 325 done:
 326         mutex_unlock(&stream->mutex);
 327         return ret;
 328 }
 329
 330 static int uvc_v4l2_get_streamparm(struct uvc_streaming *stream,
 331                 struct v4l2_streamparm *parm)
 332 {
 333         uint32_t numerator, denominator;
 334
 335         if (parm->type != stream->type)
 336                 return -EINVAL;
 337
 338         mutex_lock(&stream->mutex);
 339         numerator = stream->ctrl.dwFrameInterval;
 340         mutex_unlock(&stream->mutex);
 341
 342         denominator = 10000000;
 343         uvc_simplify_fraction(&numerator, &denominator, 8, 333);
 344
 345         memset(parm, 0, sizeof *parm);
 346         parm->type = stream->type;
 347
 348         if (stream->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
 349                 parm->parm.capture.capability = V4L2_CAP_TIMEPERFRAME;
 350                 parm->parm.capture.capturemode = 0;
 351                 parm->parm.capture.timeperframe.numerator = numerator;
 352                 parm->parm.capture.timeperframe.denominator = denominator;
 353                 parm->parm.capture.extendedmode = 0;
 354                 parm->parm.capture.readbuffers = 0;
 355         } else {
 356                 parm->parm.output.capability = V4L2_CAP_TIMEPERFRAME;
 357                 parm->parm.output.outputmode = 0;
 358                 parm->parm.output.timeperframe.numerator = numerator;
 359                 parm->parm.output.timeperframe.denominator = denominator;
 360         }
 361
 362         return 0;
 363 }
 364
 365 static int uvc_v4l2_set_streamparm(struct uvc_streaming *stream,
 366                 struct v4l2_streamparm *parm)
 367 {
 368         struct uvc_streaming_control probe;
 369         struct v4l2_fract timeperframe;
 370         uint32_t interval;
 371         int ret;
 372
 373         if (parm->type != stream->type)
 374                 return -EINVAL;
 375
 376         if (parm->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
 377                 timeperframe = parm->parm.capture.timeperframe;
 378         else
 379                 timeperframe = parm->parm.output.timeperframe;
 380
 381         interval = uvc_fraction_to_interval(timeperframe.numerator,
 382                 timeperframe.denominator);
 383         uvc_trace(UVC_TRACE_FORMAT, "Setting frame interval to %u/%u (%u).\n",
 384                 timeperframe.numerator, timeperframe.denominator, interval);
 385
 386         mutex_lock(&stream->mutex);
 387
 388         if (uvc_queue_streaming(&stream->queue)) {
 389                 mutex_unlock(&stream->mutex);
 390                 return -EBUSY;
 391         }
 392
 393         memcpy(&probe, &stream->ctrl, sizeof probe);
 394         probe.dwFrameInterval =
 395                 uvc_try_frame_interval(stream->cur_frame, interval);
 396
 397         /* Probe the device with the new settings. */
 398         ret = uvc_probe_video(stream, &probe);
 399         if (ret < 0) {
 400                 mutex_unlock(&stream->mutex);
 401                 return ret;
 402         }
 403
 404         memcpy(&stream->ctrl, &probe, sizeof probe);
 405         mutex_unlock(&stream->mutex);
 406
 407         /* Return the actual frame period. */
 408         timeperframe.numerator = probe.dwFrameInterval;
 409         timeperframe.denominator = 10000000;
 410         uvc_simplify_fraction(&timeperframe.numerator,
 411                 &timeperframe.denominator, 8, 333);
 412
 413         if (parm->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
 414                 parm->parm.capture.timeperframe = timeperframe;
 415         else
 416                 parm->parm.output.timeperframe = timeperframe;
 417
 418         return 0;
 419 }
 420
 421 /* ------------------------------------------------------------------------
 422  * Privilege management
 423  */
 424
 425 /*
 426  * Privilege management is the multiple-open implementation basis. The current
 427  * implementation is completely transparent for the end-user and doesn't
 428  * require explicit use of the VIDIOC_G_PRIORITY and VIDIOC_S_PRIORITY ioctls.
 429  * Those ioctls enable finer control on the device (by making possible for a
 430  * user to request exclusive access to a device), but are not mature yet.
 431  * Switching to the V4L2 priority mechanism might be considered in the future
 432  * if this situation changes.
 433  *
 434  * Each open instance of a UVC device can either be in a privileged or
 435  * unprivileged state. Only a single instance can be in a privileged state at
 436  * a given time. Trying to perform an operation that requires privileges will
 437  * automatically acquire the required privileges if possible, or return -EBUSY
 438  * otherwise. Privileges are dismissed when closing the instance or when
 439  * freeing the video buffers using VIDIOC_REQBUFS.
 440  *
 441  * Operations that require privileges are:
 442  *
 443  * - VIDIOC_S_INPUT
 444  * - VIDIOC_S_PARM
 445  * - VIDIOC_S_FMT
 446  * - VIDIOC_REQBUFS
 447  */
 448 static int uvc_acquire_privileges(struct uvc_fh *handle)
 449 {
 450         /* Always succeed if the handle is already privileged. */
 451         if (handle->state == UVC_HANDLE_ACTIVE)
 452                 return 0;
 453
 454         /* Check if the device already has a privileged handle. */
 455         if (atomic_inc_return(&handle->stream->active) != 1) {
 456                 atomic_dec(&handle->stream->active);
 457                 return -EBUSY;
 458         }
 459
 460         handle->state = UVC_HANDLE_ACTIVE;
 461         return 0;
 462 }
 463
 464 static void uvc_dismiss_privileges(struct uvc_fh *handle)
 465 {
 466         if (handle->state == UVC_HANDLE_ACTIVE)
 467                 atomic_dec(&handle->stream->active);
 468
 469         handle->state = UVC_HANDLE_PASSIVE;
 470 }
 471
 472 static int uvc_has_privileges(struct uvc_fh *handle)
 473 {
 474         return handle->state == UVC_HANDLE_ACTIVE;
 475 }
 476
 477 /* ------------------------------------------------------------------------
 478  * V4L2 file operations
 479  */
 480
 481 static int uvc_v4l2_open(struct file *file)
 482 {
 483         struct uvc_streaming *stream;
 484         struct uvc_fh *handle;
 485         int ret = 0;
 486
 487         uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_open\n");
 488         stream = video_drvdata(file);
 489
 490         if (stream->dev->state & UVC_DEV_DISCONNECTED)
 491                 return -ENODEV;
 492
 493         ret = usb_autopm_get_interface(stream->dev->intf);
 494         if (ret < 0)
 495                 return ret;
 496
 497         /* Create the device handle. */
 498         handle = kzalloc(sizeof *handle, GFP_KERNEL);
 499         if (handle == NULL) {
 500                 usb_autopm_put_interface(stream->dev->intf);
 501                 return -ENOMEM;
 502         }
 503
 504         if (atomic_inc_return(&stream->dev->users) == 1) {
 505                 ret = uvc_status_start(stream->dev);
 506                 if (ret < 0) {
 507                         usb_autopm_put_interface(stream->dev->intf);
 508                         atomic_dec(&stream->dev->users);
 509                         kfree(handle);
 510                         return ret;
 511                 }
 512         }
 513
 514         handle->chain = stream->chain;
 515         handle->stream = stream;
 516         handle->state = UVC_HANDLE_PASSIVE;
 517         file->private_data = handle;
 518
 519         return 0;
 520 }
 521
 522 static int uvc_v4l2_release(struct file *file)
 523 {
 524         struct uvc_fh *handle = file->private_data;
 525         struct uvc_streaming *stream = handle->stream;
 526
 527         uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_release\n");
 528
 529         /* Only free resources if this is a privileged handle. */
 530         if (uvc_has_privileges(handle)) {
 531                 uvc_video_enable(stream, 0);
 532
 533                 if (uvc_free_buffers(&stream->queue) < 0)
 534                         uvc_printk(KERN_ERR, "uvc_v4l2_release: Unable to "
 535                                         "free buffers.\n");
 536         }
 537
 538         /* Release the file handle. */
 539         uvc_dismiss_privileges(handle);
 540         kfree(handle);
 541         file->private_data = NULL;
 542
 543         if (atomic_dec_return(&stream->dev->users) == 0)
 544                 uvc_status_stop(stream->dev);
 545
 546         usb_autopm_put_interface(stream->dev->intf);
 547         return 0;
 548 }
 549
 550 static void uvc_v4l2_ioctl_warn(void)
 551 {
 552         static int warned;
 553
 554         if (warned)
 555                 return;
 556
 557         uvc_printk(KERN_INFO, "Deprecated UVCIOC_CTRL_{ADD,MAP_OLD,GET,SET} "
 558                    "ioctls will be removed in 2.6.42.\n");
 559         uvc_printk(KERN_INFO, "See http://www.ideasonboard.org/uvc/upgrade/ "
 560                    "for upgrade instructions.\n");
 561         warned = 1;
 562 }
 563
 564 static long uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 565 {
 566         struct video_device *vdev = video_devdata(file);
 567         struct uvc_fh *handle = file->private_data;
 568         struct uvc_video_chain *chain = handle->chain;
 569         struct uvc_streaming *stream = handle->stream;
 570         long ret = 0;
 571
 572         switch (cmd) {
 573         /* Query capabilities */
 574         case VIDIOC_QUERYCAP:
 575         {
 576                 struct v4l2_capability *cap = arg;
 577
 578                 memset(cap, 0, sizeof *cap);
 579                 strlcpy(cap->driver, "uvcvideo", sizeof cap->driver);
 580                 strlcpy(cap->card, vdev->name, sizeof cap->card);
 581                 usb_make_path(stream->dev->udev,
 582                               cap->bus_info, sizeof(cap->bus_info));
 583                 cap->version = DRIVER_VERSION_NUMBER;
 584                 if (stream->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
 585                         cap->capabilities = V4L2_CAP_VIDEO_CAPTURE
 586                                           | V4L2_CAP_STREAMING;
 587                 else
 588                         cap->capabilities = V4L2_CAP_VIDEO_OUTPUT
 589                                           | V4L2_CAP_STREAMING;
 590                 break;
 591         }
 592
 593         /* Get, Set & Query control */
 594         case VIDIOC_QUERYCTRL:
 595                 return uvc_query_v4l2_ctrl(chain, arg);
 596
 597         case VIDIOC_G_CTRL:
 598         {
 599                 struct v4l2_control *ctrl = arg;
 600                 struct v4l2_ext_control xctrl;
 601
 602                 memset(&xctrl, 0, sizeof xctrl);
 603                 xctrl.id = ctrl->id;
 604
 605                 ret = uvc_ctrl_begin(chain);
 606                 if (ret < 0)
 607                         return ret;
 608
 609                 ret = uvc_ctrl_get(chain, &xctrl);
 610                 uvc_ctrl_rollback(chain);
 611                 if (ret >= 0)
 612                         ctrl->value = xctrl.value;
 613                 break;
 614         }
 615
 616         case VIDIOC_S_CTRL:
 617         {
 618                 struct v4l2_control *ctrl = arg;
 619                 struct v4l2_ext_control xctrl;
 620
 621                 memset(&xctrl, 0, sizeof xctrl);
 622                 xctrl.id = ctrl->id;
 623                 xctrl.value = ctrl->value;
 624
 625                 ret = uvc_ctrl_begin(chain);
 626                 if (ret < 0)
 627                         return ret;
 628
 629                 ret = uvc_ctrl_set(chain, &xctrl);
 630                 if (ret < 0) {
 631                         uvc_ctrl_rollback(chain);
 632                         return ret;
 633                 }
 634                 ret = uvc_ctrl_commit(chain);
 635                 if (ret == 0)
 636                         ctrl->value = xctrl.value;
 637                 break;
 638         }
 639
 640         case VIDIOC_QUERYMENU:
 641                 return uvc_query_v4l2_menu(chain, arg);
 642
 643         case VIDIOC_G_EXT_CTRLS:
 644         {
 645                 struct v4l2_ext_controls *ctrls = arg;
 646                 struct v4l2_ext_control *ctrl = ctrls->controls;
 647                 unsigned int i;
 648
 649                 ret = uvc_ctrl_begin(chain);
 650                 if (ret < 0)
 651                         return ret;
 652
 653                 for (i = 0; i < ctrls->count; ++ctrl, ++i) {
 654                         ret = uvc_ctrl_get(chain, ctrl);
 655                         if (ret < 0) {
 656                                 uvc_ctrl_rollback(chain);
 657                                 ctrls->error_idx = i;
 658                                 return ret;
 659                         }
 660                 }
 661                 ctrls->error_idx = 0;
 662                 ret = uvc_ctrl_rollback(chain);
 663                 break;
 664         }
 665
 666         case VIDIOC_S_EXT_CTRLS:
 667         case VIDIOC_TRY_EXT_CTRLS:
 668         {
 669                 struct v4l2_ext_controls *ctrls = arg;
 670                 struct v4l2_ext_control *ctrl = ctrls->controls;
 671                 unsigned int i;
 672
 673                 ret = uvc_ctrl_begin(chain);
 674                 if (ret < 0)
 675                         return ret;
 676
 677                 for (i = 0; i < ctrls->count; ++ctrl, ++i) {
 678                         ret = uvc_ctrl_set(chain, ctrl);
 679                         if (ret < 0) {
 680                                 uvc_ctrl_rollback(chain);
 681                                 ctrls->error_idx = i;
 682                                 return ret;
 683                         }
 684                 }
 685
 686                 ctrls->error_idx = 0;
 687
 688                 if (cmd == VIDIOC_S_EXT_CTRLS)
 689                         ret = uvc_ctrl_commit(chain);
 690                 else
 691                         ret = uvc_ctrl_rollback(chain);
 692                 break;
 693         }
 694
 695         /* Get, Set & Enum input */
 696         case VIDIOC_ENUMINPUT:
 697         {
 698                 const struct uvc_entity *selector = chain->selector;
 699                 struct v4l2_input *input = arg;
 700                 struct uvc_entity *iterm = NULL;
 701                 u32 index = input->index;
 702                 int pin = 0;
 703
 704                 if (selector == NULL ||
 705                     (chain->dev->quirks & UVC_QUIRK_IGNORE_SELECTOR_UNIT)) {
 706                         if (index != 0)
 707                                 return -EINVAL;
 708                         list_for_each_entry(iterm, &chain->entities, chain) {
 709                                 if (UVC_ENTITY_IS_ITERM(iterm))
 710                                         break;
 711                         }
 712                         pin = iterm->id;
 713                 } else if (index < selector->bNrInPins) {
 714                         pin = selector->baSourceID[index];
 715                         list_for_each_entry(iterm, &chain->entities, chain) {
 716                                 if (!UVC_ENTITY_IS_ITERM(iterm))
 717                                         continue;
 718                                 if (iterm->id == pin)
 719                                         break;
 720                         }
 721                 }
 722
 723                 if (iterm == NULL || iterm->id != pin)
 724                         return -EINVAL;
 725
 726                 memset(input, 0, sizeof *input);
 727                 input->index = index;
 728                 strlcpy(input->name, iterm->name, sizeof input->name);
 729                 if (UVC_ENTITY_TYPE(iterm) == UVC_ITT_CAMERA)
 730                         input->type = V4L2_INPUT_TYPE_CAMERA;
 731                 break;
 732         }
 733
 734         case VIDIOC_G_INPUT:
 735         {
 736                 u8 input;
 737
 738                 if (chain->selector == NULL ||
 739                     (chain->dev->quirks & UVC_QUIRK_IGNORE_SELECTOR_UNIT)) {
 740                         *(int *)arg = 0;
 741                         break;
 742                 }
 743
 744                 ret = uvc_query_ctrl(chain->dev, UVC_GET_CUR,
 745                         chain->selector->id, chain->dev->intfnum,
 746                         UVC_SU_INPUT_SELECT_CONTROL, &input, 1);
 747                 if (ret < 0)
 748                         return ret;
 749
 750                 *(int *)arg = input - 1;
 751                 break;
 752         }
 753
 754         case VIDIOC_S_INPUT:
 755         {
 756                 u32 input = *(u32 *)arg + 1;
 757
 758                 if ((ret = uvc_acquire_privileges(handle)) < 0)
 759                         return ret;
 760
 761                 if (chain->selector == NULL ||
 762                     (chain->dev->quirks & UVC_QUIRK_IGNORE_SELECTOR_UNIT)) {
 763                         if (input != 1)
 764                                 return -EINVAL;
 765                         break;
 766                 }
 767
 768                 if (input == 0 || input > chain->selector->bNrInPins)
 769                         return -EINVAL;
 770
 771                 return uvc_query_ctrl(chain->dev, UVC_SET_CUR,
 772                         chain->selector->id, chain->dev->intfnum,
 773                         UVC_SU_INPUT_SELECT_CONTROL, &input, 1);
 774         }
 775
 776         /* Try, Get, Set & Enum format */
 777         case VIDIOC_ENUM_FMT:
 778         {
 779                 struct v4l2_fmtdesc *fmt = arg;
 780                 struct uvc_format *format;
 781                 enum v4l2_buf_type type = fmt->type;
 782                 __u32 index = fmt->index;
 783
 784                 if (fmt->type != stream->type ||
 785                     fmt->index >= stream->nformats)
 786                         return -EINVAL;
 787
 788                 memset(fmt, 0, sizeof(*fmt));
 789                 fmt->index = index;
 790                 fmt->type = type;
 791
 792                 format = &stream->format[fmt->index];
 793                 fmt->flags = 0;
 794                 if (format->flags & UVC_FMT_FLAG_COMPRESSED)
 795                         fmt->flags |= V4L2_FMT_FLAG_COMPRESSED;
 796                 strlcpy(fmt->description, format->name,
 797                         sizeof fmt->description);
 798                 fmt->description[sizeof fmt->description - 1] = 0;
 799                 fmt->pixelformat = format->fcc;
 800                 break;
 801         }
 802
 803         case VIDIOC_TRY_FMT:
 804         {
 805                 struct uvc_streaming_control probe;
 806
 807                 return uvc_v4l2_try_format(stream, arg, &probe, NULL, NULL);
 808         }
 809
 810         case VIDIOC_S_FMT:
 811                 if ((ret = uvc_acquire_privileges(handle)) < 0)
 812                         return ret;
 813
 814                 return uvc_v4l2_set_format(stream, arg);
 815
 816         case VIDIOC_G_FMT:
 817                 return uvc_v4l2_get_format(stream, arg);
 818
 819         /* Frame size enumeration */
 820         case VIDIOC_ENUM_FRAMESIZES:
 821         {
 822                 struct v4l2_frmsizeenum *fsize = arg;
 823                 struct uvc_format *format = NULL;
 824                 struct uvc_frame *frame;
 825                 int i;
 826
 827                 /* Look for the given pixel format */
 828                 for (i = 0; i < stream->nformats; i++) {
 829                         if (stream->format[i].fcc ==
 830                                         fsize->pixel_format) {
 831                                 format = &stream->format[i];
 832                                 break;
 833                         }
 834                 }
 835                 if (format == NULL)
 836                         return -EINVAL;
 837
 838                 if (fsize->index >= format->nframes)
 839                         return -EINVAL;
 840
 841                 frame = &format->frame[fsize->index];
 842                 fsize->type = V4L2_FRMSIZE_TYPE_DISCRETE;
 843                 fsize->discrete.width = frame->wWidth;
 844                 fsize->discrete.height = frame->wHeight;
 845                 break;
 846         }
 847
 848         /* Frame interval enumeration */
 849         case VIDIOC_ENUM_FRAMEINTERVALS:
 850         {
 851                 struct v4l2_frmivalenum *fival = arg;
 852                 struct uvc_format *format = NULL;
 853                 struct uvc_frame *frame = NULL;
 854                 int i;
 855
 856                 /* Look for the given pixel format and frame size */
 857                 for (i = 0; i < stream->nformats; i++) {
 858                         if (stream->format[i].fcc ==
 859                                         fival->pixel_format) {
 860                                 format = &stream->format[i];
 861                                 break;
 862                         }
 863                 }
 864                 if (format == NULL)
 865                         return -EINVAL;
 866
 867                 for (i = 0; i < format->nframes; i++) {
 868                         if (format->frame[i].wWidth == fival->width &&
 869                             format->frame[i].wHeight == fival->height) {
 870                                 frame = &format->frame[i];
 871                                 break;
 872                         }
 873                 }
 874                 if (frame == NULL)
 875                         return -EINVAL;
 876
 877                 if (frame->bFrameIntervalType) {
 878                         if (fival->index >= frame->bFrameIntervalType)
 879                                 return -EINVAL;
 880
 881                         fival->type = V4L2_FRMIVAL_TYPE_DISCRETE;
 882                         fival->discrete.numerator =
 883                                 frame->dwFrameInterval[fival->index];
 884                         fival->discrete.denominator = 10000000;
 885                         uvc_simplify_fraction(&fival->discrete.numerator,
 886                                 &fival->discrete.denominator, 8, 333);
 887                 } else {
 888                         fival->type = V4L2_FRMIVAL_TYPE_STEPWISE;
 889                         fival->stepwise.min.numerator =
 890                                 frame->dwFrameInterval[0];
 891                         fival->stepwise.min.denominator = 10000000;
 892                         fival->stepwise.max.numerator =
 893                                 frame->dwFrameInterval[1];
 894                         fival->stepwise.max.denominator = 10000000;
 895                         fival->stepwise.step.numerator =
 896                                 frame->dwFrameInterval[2];
 897                         fival->stepwise.step.denominator = 10000000;
 898                         uvc_simplify_fraction(&fival->stepwise.min.numerator,
 899                                 &fival->stepwise.min.denominator, 8, 333);
 900                         uvc_simplify_fraction(&fival->stepwise.max.numerator,
 901                                 &fival->stepwise.max.denominator, 8, 333);
 902                         uvc_simplify_fraction(&fival->stepwise.step.numerator,
 903                                 &fival->stepwise.step.denominator, 8, 333);
 904                 }
 905                 break;
 906         }
 907
 908         /* Get & Set streaming parameters */
 909         case VIDIOC_G_PARM:
 910                 return uvc_v4l2_get_streamparm(stream, arg);
 911
 912         case VIDIOC_S_PARM:
 913                 if ((ret = uvc_acquire_privileges(handle)) < 0)
 914                         return ret;
 915
 916                 return uvc_v4l2_set_streamparm(stream, arg);
 917
 918         /* Cropping and scaling */
 919         case VIDIOC_CROPCAP:
 920         {
 921                 struct v4l2_cropcap *ccap = arg;
 922
 923                 if (ccap->type != stream->type)
 924                         return -EINVAL;
 925
 926                 ccap->bounds.left = 0;
 927                 ccap->bounds.top = 0;
 928
 929                 mutex_lock(&stream->mutex);
 930                 ccap->bounds.width = stream->cur_frame->wWidth;
 931                 ccap->bounds.height = stream->cur_frame->wHeight;
 932                 mutex_unlock(&stream->mutex);
 933
 934                 ccap->defrect = ccap->bounds;
 935
 936                 ccap->pixelaspect.numerator = 1;
 937                 ccap->pixelaspect.denominator = 1;
 938                 break;
 939         }
 940
 941         case VIDIOC_G_CROP:
 942         case VIDIOC_S_CROP:
 943                 return -EINVAL;
 944
 945         /* Buffers & streaming */
 946         case VIDIOC_REQBUFS:
 947         {
 948                 struct v4l2_requestbuffers *rb = arg;
 949
 950                 if (rb->type != stream->type ||
 951                     rb->memory != V4L2_MEMORY_MMAP)
 952                         return -EINVAL;
 953
 954                 if ((ret = uvc_acquire_privileges(handle)) < 0)
 955                         return ret;
 956
 957                 mutex_lock(&stream->mutex);
 958                 ret = uvc_alloc_buffers(&stream->queue, rb->count,
 959                                         stream->ctrl.dwMaxVideoFrameSize);
 960                 mutex_unlock(&stream->mutex);
 961                 if (ret < 0)
 962                         return ret;
 963
 964                 if (ret == 0)
 965                         uvc_dismiss_privileges(handle);
 966
 967                 rb->count = ret;
 968                 ret = 0;
 969                 break;
 970         }
 971
 972         case VIDIOC_QUERYBUF:
 973         {
 974                 struct v4l2_buffer *buf = arg;
 975
 976                 if (buf->type != stream->type)
 977                         return -EINVAL;
 978
 979                 if (!uvc_has_privileges(handle))
 980                         return -EBUSY;
 981
 982                 return uvc_query_buffer(&stream->queue, buf);
 983         }
 984
 985         case VIDIOC_QBUF:
 986                 if (!uvc_has_privileges(handle))
 987                         return -EBUSY;
 988
 989                 return uvc_queue_buffer(&stream->queue, arg);
 990
 991         case VIDIOC_DQBUF:
 992                 if (!uvc_has_privileges(handle))
 993                         return -EBUSY;
 994
 995                 return uvc_dequeue_buffer(&stream->queue, arg,
 996                         file->f_flags & O_NONBLOCK);
 997
 998         case VIDIOC_STREAMON:
 999         {
1000                 int *type = arg;
1001
1002                 if (*type != stream->type)
1003                         return -EINVAL;
1004
1005                 if (!uvc_has_privileges(handle))
1006                         return -EBUSY;
1007
1008                 mutex_lock(&stream->mutex);
1009                 ret = uvc_video_enable(stream, 1);
1010                 mutex_unlock(&stream->mutex);
1011                 if (ret < 0)
1012                         return ret;
1013                 break;
1014         }
1015
1016         case VIDIOC_STREAMOFF:
1017         {
1018                 int *type = arg;
1019
1020                 if (*type != stream->type)
1021                         return -EINVAL;
1022
1023                 if (!uvc_has_privileges(handle))
1024                         return -EBUSY;
1025
1026                 return uvc_video_enable(stream, 0);
1027         }
1028
1029         /* Analog video standards make no sense for digital cameras. */
1030         case VIDIOC_ENUMSTD:
1031         case VIDIOC_QUERYSTD:
1032         case VIDIOC_G_STD:
1033         case VIDIOC_S_STD:
1034
1035         case VIDIOC_OVERLAY:
1036
1037         case VIDIOC_ENUMAUDIO:
1038         case VIDIOC_ENUMAUDOUT:
1039
1040         case VIDIOC_ENUMOUTPUT:
1041                 uvc_trace(UVC_TRACE_IOCTL, "Unsupported ioctl 0x%08x\n", cmd);
1042                 return -EINVAL;
1043
1044         /* Dynamic controls. UVCIOC_CTRL_ADD, UVCIOC_CTRL_MAP_OLD,
1045          * UVCIOC_CTRL_GET and UVCIOC_CTRL_SET are deprecated and scheduled for
1046          * removal in 2.6.42.
1047          */
1048         case __UVCIOC_CTRL_ADD:
1049                 uvc_v4l2_ioctl_warn();
1050                 return -EEXIST;
1051
1052         case __UVCIOC_CTRL_MAP_OLD:
1053                 uvc_v4l2_ioctl_warn();
1054         case __UVCIOC_CTRL_MAP:
1055         case UVCIOC_CTRL_MAP:
1056                 return uvc_ioctl_ctrl_map(chain, arg,
1057                                           cmd == __UVCIOC_CTRL_MAP_OLD);
1058
1059         case __UVCIOC_CTRL_GET:
1060         case __UVCIOC_CTRL_SET:
1061         {
1062                 struct uvc_xu_control *xctrl = arg;
1063                 struct uvc_xu_control_query xqry = {
1064                         .unit           = xctrl->unit,
1065                         .selector       = xctrl->selector,
1066                         .query          = cmd == __UVCIOC_CTRL_GET
1067                                         ? UVC_GET_CUR : UVC_SET_CUR,
1068                         .size           = xctrl->size,
1069                         .data           = xctrl->data,
1070                 };
1071
1072                 uvc_v4l2_ioctl_warn();
1073                 return uvc_xu_ctrl_query(chain, &xqry);
1074         }
1075
1076         case UVCIOC_CTRL_QUERY:
1077                 return uvc_xu_ctrl_query(chain, arg);
1078
1079         default:
1080                 uvc_trace(UVC_TRACE_IOCTL, "Unknown ioctl 0x%08x\n", cmd);
1081                 return -EINVAL;
1082         }
1083
1084         return ret;
1085 }
1086
1087 static long uvc_v4l2_ioctl(struct file *file,
1088                      unsigned int cmd, unsigned long arg)
1089 {
1090         if (uvc_trace_param & UVC_TRACE_IOCTL) {
1091                 uvc_printk(KERN_DEBUG, "uvc_v4l2_ioctl(");
1092                 v4l_printk_ioctl(cmd);
1093                 printk(")\n");
1094         }
1095
1096         return video_usercopy(file, cmd, arg, uvc_v4l2_do_ioctl);
1097 }
1098
1099 static ssize_t uvc_v4l2_read(struct file *file, char __user *data,
1100                     size_t count, loff_t *ppos)
1101 {
1102         uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_read: not implemented.\n");
1103         return -EINVAL;
1104 }
1105
1106 static int uvc_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
1107 {
1108         struct uvc_fh *handle = file->private_data;
1109         struct uvc_streaming *stream = handle->stream;
1110
1111         uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_mmap\n");
1112
1113         return uvc_queue_mmap(&stream->queue, vma);
1114 }
1115
1116 static unsigned int uvc_v4l2_poll(struct file *file, poll_table *wait)
1117 {
1118         struct uvc_fh *handle = file->private_data;
1119         struct uvc_streaming *stream = handle->stream;
1120
1121         uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_poll\n");
1122
1123         return uvc_queue_poll(&stream->queue, file, wait);
1124 }
1125
1126 #ifndef CONFIG_MMU
1127 static unsigned long uvc_v4l2_get_unmapped_area(struct file *file,
1128                 unsigned long addr, unsigned long len, unsigned long pgoff,
1129                 unsigned long flags)
1130 {
1131         struct uvc_fh *handle = file->private_data;
1132         struct uvc_streaming *stream = handle->stream;
1133
1134         uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_get_unmapped_area\n");
1135
1136         return uvc_queue_get_unmapped_area(&stream->queue, pgoff);
1137 }
1138 #endif
1139
1140 const struct v4l2_file_operations uvc_fops = {
1141         .owner          = THIS_MODULE,
1142         .open           = uvc_v4l2_open,
1143         .release        = uvc_v4l2_release,
1144         .unlocked_ioctl = uvc_v4l2_ioctl,
1145         .read           = uvc_v4l2_read,
1146         .mmap           = uvc_v4l2_mmap,
1147         .poll           = uvc_v4l2_poll,
1148 #ifndef CONFIG_MMU
1149         .get_unmapped_area = uvc_v4l2_get_unmapped_area,
1150 #endif
1151 };
1152