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