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/compat.h>
  15 #include <linux/kernel.h>
  16 #include <linux/version.h>
  17 #include <linux/list.h>
  18 #include <linux/module.h>
  19 #include <linux/slab.h>
  20 #include <linux/usb.h>
  21 #include <linux/videodev2.h>
  22 #include <linux/vmalloc.h>
  23 #include <linux/mm.h>
  24 #include <linux/wait.h>
  25 #include <linux/atomic.h>
  26
  27 #include <media/v4l2-common.h>
  28 #include <media/v4l2-ioctl.h>
  29
  30 #include "uvcvideo.h"
  31
  32 /* ------------------------------------------------------------------------
  33  * UVC ioctls
  34  */
  35 static int uvc_ioctl_ctrl_map(struct uvc_video_chain *chain,
  36         struct uvc_xu_control_mapping *xmap)
  37 {
  38         struct uvc_control_mapping *map;
  39         unsigned int size;
  40         int ret;
  41
  42         map = kzalloc(sizeof *map, GFP_KERNEL);
  43         if (map == NULL)
  44                 return -ENOMEM;
  45
  46         map->id = xmap->id;
  47         memcpy(map->name, xmap->name, sizeof map->name);
  48         memcpy(map->entity, xmap->entity, sizeof map->entity);
  49         map->selector = xmap->selector;
  50         map->size = xmap->size;
  51         map->offset = xmap->offset;
  52         map->v4l2_type = xmap->v4l2_type;
  53         map->data_type = xmap->data_type;
  54
  55         switch (xmap->v4l2_type) {
  56         case V4L2_CTRL_TYPE_INTEGER:
  57         case V4L2_CTRL_TYPE_BOOLEAN:
  58         case V4L2_CTRL_TYPE_BUTTON:
  59                 break;
  60
  61         case V4L2_CTRL_TYPE_MENU:
  62                 /* Prevent excessive memory consumption, as well as integer
  63                  * overflows.
  64                  */
  65                 if (xmap->menu_count == 0 ||
  66                     xmap->menu_count > UVC_MAX_CONTROL_MENU_ENTRIES) {
  67                         ret = -EINVAL;
  68                         goto done;
  69                 }
  70
  71                 size = xmap->menu_count * sizeof(*map->menu_info);
  72                 map->menu_info = kmalloc(size, GFP_KERNEL);
  73                 if (map->menu_info == NULL) {
  74                         ret = -ENOMEM;
  75                         goto done;
  76                 }
  77
  78                 if (copy_from_user(map->menu_info, xmap->menu_info, size)) {
  79                         ret = -EFAULT;
  80                         goto done;
  81                 }
  82
  83                 map->menu_count = xmap->menu_count;
  84                 break;
  85
  86         default:
  87                 uvc_trace(UVC_TRACE_CONTROL, "Unsupported V4L2 control type "
  88                           "%u.\n", xmap->v4l2_type);
  89                 ret = -ENOTTY;
  90                 goto done;
  91         }
  92
  93         ret = uvc_ctrl_add_mapping(chain, map);
  94
  95 done:
  96         kfree(map->menu_info);
  97         kfree(map);
  98
  99         return ret;
 100 }
 101
 102 /* ------------------------------------------------------------------------
 103  * V4L2 interface
 104  */
 105
 106 /*
 107  * Find the frame interval closest to the requested frame interval for the
 108  * given frame format and size. This should be done by the device as part of
 109  * the Video Probe and Commit negotiation, but some hardware don't implement
 110  * that feature.
 111  */
 112 static __u32 uvc_try_frame_interval(struct uvc_frame *frame, __u32 interval)
 113 {
 114         unsigned int i;
 115
 116         if (frame->bFrameIntervalType) {
 117                 __u32 best = -1, dist;
 118
 119                 for (i = 0; i < frame->bFrameIntervalType; ++i) {
 120                         dist = interval > frame->dwFrameInterval[i]
 121                              ? interval - frame->dwFrameInterval[i]
 122                              : frame->dwFrameInterval[i] - interval;
 123
 124                         if (dist > best)
 125                                 break;
 126
 127                         best = dist;
 128                 }
 129
 130                 interval = frame->dwFrameInterval[i-1];
 131         } else {
 132                 const __u32 min = frame->dwFrameInterval[0];
 133                 const __u32 max = frame->dwFrameInterval[1];
 134                 const __u32 step = frame->dwFrameInterval[2];
 135
 136                 interval = min + (interval - min + step/2) / step * step;
 137                 if (interval > max)
 138                         interval = max;
 139         }
 140
 141         return interval;
 142 }
 143
 144 static int uvc_v4l2_try_format(struct uvc_streaming *stream,
 145         struct v4l2_format *fmt, struct uvc_streaming_control *probe,
 146         struct uvc_format **uvc_format, struct uvc_frame **uvc_frame)
 147 {
 148         struct uvc_format *format = NULL;
 149         struct uvc_frame *frame = NULL;
 150         __u16 rw, rh;
 151         unsigned int d, maxd;
 152         unsigned int i;
 153         __u32 interval;
 154         int ret = 0;
 155         __u8 *fcc;
 156
 157         if (fmt->type != stream->type)
 158                 return -EINVAL;
 159
 160         fcc = (__u8 *)&fmt->fmt.pix.pixelformat;
 161         uvc_trace(UVC_TRACE_FORMAT, "Trying format 0x%08x (%c%c%c%c): %ux%u.\n",
 162                         fmt->fmt.pix.pixelformat,
 163                         fcc[0], fcc[1], fcc[2], fcc[3],
 164                         fmt->fmt.pix.width, fmt->fmt.pix.height);
 165
 166         /* Check if the hardware supports the requested format. */
 167         for (i = 0; i < stream->nformats; ++i) {
 168                 format = &stream->format[i];
 169                 if (format->fcc == fmt->fmt.pix.pixelformat)
 170                         break;
 171         }
 172
 173         if (format == NULL || format->fcc != fmt->fmt.pix.pixelformat) {
 174                 uvc_trace(UVC_TRACE_FORMAT, "Unsupported format 0x%08x.\n",
 175                                 fmt->fmt.pix.pixelformat);
 176                 return -EINVAL;
 177         }
 178
 179         /* Find the closest image size. The distance between image sizes is
 180          * the size in pixels of the non-overlapping regions between the
 181          * requested size and the frame-specified size.
 182          */
 183         rw = fmt->fmt.pix.width;
 184         rh = fmt->fmt.pix.height;
 185         maxd = (unsigned int)-1;
 186
 187         for (i = 0; i < format->nframes; ++i) {
 188                 __u16 w = format->frame[i].wWidth;
 189                 __u16 h = format->frame[i].wHeight;
 190
 191                 d = min(w, rw) * min(h, rh);
 192                 d = w*h + rw*rh - 2*d;
 193                 if (d < maxd) {
 194                         maxd = d;
 195                         frame = &format->frame[i];
 196                 }
 197
 198                 if (maxd == 0)
 199                         break;
 200         }
 201
 202         if (frame == NULL) {
 203                 uvc_trace(UVC_TRACE_FORMAT, "Unsupported size %ux%u.\n",
 204                                 fmt->fmt.pix.width, fmt->fmt.pix.height);
 205                 return -EINVAL;
 206         }
 207
 208         /* Use the default frame interval. */
 209         interval = frame->dwDefaultFrameInterval;
 210         uvc_trace(UVC_TRACE_FORMAT, "Using default frame interval %u.%u us "
 211                 "(%u.%u fps).\n", interval/10, interval%10, 10000000/interval,
 212                 (100000000/interval)%10);
 213
 214         /* Set the format index, frame index and frame interval. */
 215         memset(probe, 0, sizeof *probe);
 216         probe->bmHint = 1;      /* dwFrameInterval */
 217         probe->bFormatIndex = format->index;
 218         probe->bFrameIndex = frame->bFrameIndex;
 219         probe->dwFrameInterval = uvc_try_frame_interval(frame, interval);
 220         /* Some webcams stall the probe control set request when the
 221          * dwMaxVideoFrameSize field is set to zero. The UVC specification
 222          * clearly states that the field is read-only from the host, so this
 223          * is a webcam bug. Set dwMaxVideoFrameSize to the value reported by
 224          * the webcam to work around the problem.
 225          *
 226          * The workaround could probably be enabled for all webcams, so the
 227          * quirk can be removed if needed. It's currently useful to detect
 228          * webcam bugs and fix them before they hit the market (providing
 229          * developers test their webcams with the Linux driver as well as with
 230          * the Windows driver).
 231          */
 232         mutex_lock(&stream->mutex);
 233         if (stream->dev->quirks & UVC_QUIRK_PROBE_EXTRAFIELDS)
 234                 probe->dwMaxVideoFrameSize =
 235                         stream->ctrl.dwMaxVideoFrameSize;
 236
 237         /* Probe the device. */
 238         ret = uvc_probe_video(stream, probe);
 239         mutex_unlock(&stream->mutex);
 240         if (ret < 0)
 241                 goto done;
 242
 243         fmt->fmt.pix.width = frame->wWidth;
 244         fmt->fmt.pix.height = frame->wHeight;
 245         fmt->fmt.pix.field = V4L2_FIELD_NONE;
 246         fmt->fmt.pix.bytesperline = format->bpp * frame->wWidth / 8;
 247         fmt->fmt.pix.sizeimage = probe->dwMaxVideoFrameSize;
 248         fmt->fmt.pix.colorspace = format->colorspace;
 249         fmt->fmt.pix.priv = 0;
 250
 251         if (uvc_format != NULL)
 252                 *uvc_format = format;
 253         if (uvc_frame != NULL)
 254                 *uvc_frame = frame;
 255
 256 done:
 257         return ret;
 258 }
 259
 260 static int uvc_v4l2_get_format(struct uvc_streaming *stream,
 261         struct v4l2_format *fmt)
 262 {
 263         struct uvc_format *format;
 264         struct uvc_frame *frame;
 265         int ret = 0;
 266
 267         if (fmt->type != stream->type)
 268                 return -EINVAL;
 269
 270         mutex_lock(&stream->mutex);
 271         format = stream->cur_format;
 272         frame = stream->cur_frame;
 273
 274         if (format == NULL || frame == NULL) {
 275                 ret = -EINVAL;
 276                 goto done;
 277         }
 278
 279         fmt->fmt.pix.pixelformat = format->fcc;
 280         fmt->fmt.pix.width = frame->wWidth;
 281         fmt->fmt.pix.height = frame->wHeight;
 282         fmt->fmt.pix.field = V4L2_FIELD_NONE;
 283         fmt->fmt.pix.bytesperline = format->bpp * frame->wWidth / 8;
 284         fmt->fmt.pix.sizeimage = stream->ctrl.dwMaxVideoFrameSize;
 285         fmt->fmt.pix.colorspace = format->colorspace;
 286         fmt->fmt.pix.priv = 0;
 287
 288 done:
 289         mutex_unlock(&stream->mutex);
 290         return ret;
 291 }
 292
 293 static int uvc_v4l2_set_format(struct uvc_streaming *stream,
 294         struct v4l2_format *fmt)
 295 {
 296         struct uvc_streaming_control probe;
 297         struct uvc_format *format;
 298         struct uvc_frame *frame;
 299         int ret;
 300
 301         if (fmt->type != stream->type)
 302                 return -EINVAL;
 303
 304         ret = uvc_v4l2_try_format(stream, fmt, &probe, &format, &frame);
 305         if (ret < 0)
 306                 return ret;
 307
 308         mutex_lock(&stream->mutex);
 309
 310         if (uvc_queue_allocated(&stream->queue)) {
 311                 ret = -EBUSY;
 312                 goto done;
 313         }
 314
 315         memcpy(&stream->ctrl, &probe, sizeof probe);
 316         stream->cur_format = format;
 317         stream->cur_frame = frame;
 318
 319 done:
 320         mutex_unlock(&stream->mutex);
 321         return ret;
 322 }
 323
 324 static int uvc_v4l2_get_streamparm(struct uvc_streaming *stream,
 325                 struct v4l2_streamparm *parm)
 326 {
 327         uint32_t numerator, denominator;
 328
 329         if (parm->type != stream->type)
 330                 return -EINVAL;
 331
 332         mutex_lock(&stream->mutex);
 333         numerator = stream->ctrl.dwFrameInterval;
 334         mutex_unlock(&stream->mutex);
 335
 336         denominator = 10000000;
 337         uvc_simplify_fraction(&numerator, &denominator, 8, 333);
 338
 339         memset(parm, 0, sizeof *parm);
 340         parm->type = stream->type;
 341
 342         if (stream->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
 343                 parm->parm.capture.capability = V4L2_CAP_TIMEPERFRAME;
 344                 parm->parm.capture.capturemode = 0;
 345                 parm->parm.capture.timeperframe.numerator = numerator;
 346                 parm->parm.capture.timeperframe.denominator = denominator;
 347                 parm->parm.capture.extendedmode = 0;
 348                 parm->parm.capture.readbuffers = 0;
 349         } else {
 350                 parm->parm.output.capability = V4L2_CAP_TIMEPERFRAME;
 351                 parm->parm.output.outputmode = 0;
 352                 parm->parm.output.timeperframe.numerator = numerator;
 353                 parm->parm.output.timeperframe.denominator = denominator;
 354         }
 355
 356         return 0;
 357 }
 358
 359 static int uvc_v4l2_set_streamparm(struct uvc_streaming *stream,
 360                 struct v4l2_streamparm *parm)
 361 {
 362         struct uvc_streaming_control probe;
 363         struct v4l2_fract timeperframe;
 364         uint32_t interval;
 365         int ret;
 366
 367         if (parm->type != stream->type)
 368                 return -EINVAL;
 369
 370         if (parm->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
 371                 timeperframe = parm->parm.capture.timeperframe;
 372         else
 373                 timeperframe = parm->parm.output.timeperframe;
 374
 375         interval = uvc_fraction_to_interval(timeperframe.numerator,
 376                 timeperframe.denominator);
 377         uvc_trace(UVC_TRACE_FORMAT, "Setting frame interval to %u/%u (%u).\n",
 378                 timeperframe.numerator, timeperframe.denominator, interval);
 379
 380         mutex_lock(&stream->mutex);
 381
 382         if (uvc_queue_streaming(&stream->queue)) {
 383                 mutex_unlock(&stream->mutex);
 384                 return -EBUSY;
 385         }
 386
 387         memcpy(&probe, &stream->ctrl, sizeof probe);
 388         probe.dwFrameInterval =
 389                 uvc_try_frame_interval(stream->cur_frame, interval);
 390
 391         /* Probe the device with the new settings. */
 392         ret = uvc_probe_video(stream, &probe);
 393         if (ret < 0) {
 394                 mutex_unlock(&stream->mutex);
 395                 return ret;
 396         }
 397
 398         memcpy(&stream->ctrl, &probe, sizeof probe);
 399         mutex_unlock(&stream->mutex);
 400
 401         /* Return the actual frame period. */
 402         timeperframe.numerator = probe.dwFrameInterval;
 403         timeperframe.denominator = 10000000;
 404         uvc_simplify_fraction(&timeperframe.numerator,
 405                 &timeperframe.denominator, 8, 333);
 406
 407         if (parm->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
 408                 parm->parm.capture.timeperframe = timeperframe;
 409         else
 410                 parm->parm.output.timeperframe = timeperframe;
 411
 412         return 0;
 413 }
 414
 415 /* ------------------------------------------------------------------------
 416  * Privilege management
 417  */
 418
 419 /*
 420  * Privilege management is the multiple-open implementation basis. The current
 421  * implementation is completely transparent for the end-user and doesn't
 422  * require explicit use of the VIDIOC_G_PRIORITY and VIDIOC_S_PRIORITY ioctls.
 423  * Those ioctls enable finer control on the device (by making possible for a
 424  * user to request exclusive access to a device), but are not mature yet.
 425  * Switching to the V4L2 priority mechanism might be considered in the future
 426  * if this situation changes.
 427  *
 428  * Each open instance of a UVC device can either be in a privileged or
 429  * unprivileged state. Only a single instance can be in a privileged state at
 430  * a given time. Trying to perform an operation that requires privileges will
 431  * automatically acquire the required privileges if possible, or return -EBUSY
 432  * otherwise. Privileges are dismissed when closing the instance or when
 433  * freeing the video buffers using VIDIOC_REQBUFS.
 434  *
 435  * Operations that require privileges are:
 436  *
 437  * - VIDIOC_S_INPUT
 438  * - VIDIOC_S_PARM
 439  * - VIDIOC_S_FMT
 440  * - VIDIOC_REQBUFS
 441  */
 442 static int uvc_acquire_privileges(struct uvc_fh *handle)
 443 {
 444         /* Always succeed if the handle is already privileged. */
 445         if (handle->state == UVC_HANDLE_ACTIVE)
 446                 return 0;
 447
 448         /* Check if the device already has a privileged handle. */
 449         if (atomic_inc_return(&handle->stream->active) != 1) {
 450                 atomic_dec(&handle->stream->active);
 451                 return -EBUSY;
 452         }
 453
 454         handle->state = UVC_HANDLE_ACTIVE;
 455         return 0;
 456 }
 457
 458 static void uvc_dismiss_privileges(struct uvc_fh *handle)
 459 {
 460         if (handle->state == UVC_HANDLE_ACTIVE)
 461                 atomic_dec(&handle->stream->active);
 462
 463         handle->state = UVC_HANDLE_PASSIVE;
 464 }
 465
 466 static int uvc_has_privileges(struct uvc_fh *handle)
 467 {
 468         return handle->state == UVC_HANDLE_ACTIVE;
 469 }
 470
 471 /* ------------------------------------------------------------------------
 472  * V4L2 file operations
 473  */
 474
 475 static int uvc_v4l2_open(struct file *file)
 476 {
 477         struct uvc_streaming *stream;
 478         struct uvc_fh *handle;
 479         int ret = 0;
 480
 481         uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_open\n");
 482         stream = video_drvdata(file);
 483
 484         if (stream->dev->state & UVC_DEV_DISCONNECTED)
 485                 return -ENODEV;
 486
 487         ret = usb_autopm_get_interface(stream->dev->intf);
 488         if (ret < 0)
 489                 return ret;
 490
 491         /* Create the device handle. */
 492         handle = kzalloc(sizeof *handle, GFP_KERNEL);
 493         if (handle == NULL) {
 494                 usb_autopm_put_interface(stream->dev->intf);
 495                 return -ENOMEM;
 496         }
 497
 498         if (atomic_inc_return(&stream->dev->users) == 1) {
 499                 ret = uvc_status_start(stream->dev);
 500                 if (ret < 0) {
 501                         usb_autopm_put_interface(stream->dev->intf);
 502                         atomic_dec(&stream->dev->users);
 503                         kfree(handle);
 504                         return ret;
 505                 }
 506         }
 507
 508         handle->chain = stream->chain;
 509         handle->stream = stream;
 510         handle->state = UVC_HANDLE_PASSIVE;
 511         file->private_data = handle;
 512
 513         return 0;
 514 }
 515
 516 static int uvc_v4l2_release(struct file *file)
 517 {
 518         struct uvc_fh *handle = file->private_data;
 519         struct uvc_streaming *stream = handle->stream;
 520
 521         uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_release\n");
 522
 523         /* Only free resources if this is a privileged handle. */
 524         if (uvc_has_privileges(handle)) {
 525                 uvc_video_enable(stream, 0);
 526                 uvc_free_buffers(&stream->queue);
 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 = LINUX_VERSION_CODE;
 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                 if ((ret = uvc_acquire_privileges(handle)) < 0)
 925                         return ret;
 926
 927                 mutex_lock(&stream->mutex);
 928                 ret = uvc_alloc_buffers(&stream->queue, arg);
 929                 mutex_unlock(&stream->mutex);
 930                 if (ret < 0)
 931                         return ret;
 932
 933                 if (ret == 0)
 934                         uvc_dismiss_privileges(handle);
 935
 936                 ret = 0;
 937                 break;
 938
 939         case VIDIOC_QUERYBUF:
 940         {
 941                 struct v4l2_buffer *buf = arg;
 942
 943                 if (!uvc_has_privileges(handle))
 944                         return -EBUSY;
 945
 946                 return uvc_query_buffer(&stream->queue, buf);
 947         }
 948
 949         case VIDIOC_QBUF:
 950                 if (!uvc_has_privileges(handle))
 951                         return -EBUSY;
 952
 953                 return uvc_queue_buffer(&stream->queue, arg);
 954
 955         case VIDIOC_DQBUF:
 956                 if (!uvc_has_privileges(handle))
 957                         return -EBUSY;
 958
 959                 return uvc_dequeue_buffer(&stream->queue, arg,
 960                         file->f_flags & O_NONBLOCK);
 961
 962         case VIDIOC_STREAMON:
 963         {
 964                 int *type = arg;
 965
 966                 if (*type != stream->type)
 967                         return -EINVAL;
 968
 969                 if (!uvc_has_privileges(handle))
 970                         return -EBUSY;
 971
 972                 mutex_lock(&stream->mutex);
 973                 ret = uvc_video_enable(stream, 1);
 974                 mutex_unlock(&stream->mutex);
 975                 if (ret < 0)
 976                         return ret;
 977                 break;
 978         }
 979
 980         case VIDIOC_STREAMOFF:
 981         {
 982                 int *type = arg;
 983
 984                 if (*type != stream->type)
 985                         return -EINVAL;
 986
 987                 if (!uvc_has_privileges(handle))
 988                         return -EBUSY;
 989
 990                 return uvc_video_enable(stream, 0);
 991         }
 992
 993         /* Analog video standards make no sense for digital cameras. */
 994         case VIDIOC_ENUMSTD:
 995         case VIDIOC_QUERYSTD:
 996         case VIDIOC_G_STD:
 997         case VIDIOC_S_STD:
 998
 999         case VIDIOC_OVERLAY:
1000
1001         case VIDIOC_ENUMAUDIO:
1002         case VIDIOC_ENUMAUDOUT:
1003
1004         case VIDIOC_ENUMOUTPUT:
1005                 uvc_trace(UVC_TRACE_IOCTL, "Unsupported ioctl 0x%08x\n", cmd);
1006                 return -EINVAL;
1007
1008         case UVCIOC_CTRL_MAP:
1009                 return uvc_ioctl_ctrl_map(chain, arg);
1010
1011         case UVCIOC_CTRL_QUERY:
1012                 return uvc_xu_ctrl_query(chain, arg);
1013
1014         default:
1015                 uvc_trace(UVC_TRACE_IOCTL, "Unknown ioctl 0x%08x\n", cmd);
1016                 return -ENOTTY;
1017         }
1018
1019         return ret;
1020 }
1021
1022 static long uvc_v4l2_ioctl(struct file *file,
1023                      unsigned int cmd, unsigned long arg)
1024 {
1025         if (uvc_trace_param & UVC_TRACE_IOCTL) {
1026                 uvc_printk(KERN_DEBUG, "uvc_v4l2_ioctl(");
1027                 v4l_printk_ioctl(cmd);
1028                 printk(")\n");
1029         }
1030
1031         return video_usercopy(file, cmd, arg, uvc_v4l2_do_ioctl);
1032 }
1033
1034 #ifdef CONFIG_COMPAT
1035 struct uvc_xu_control_mapping32 {
1036         __u32 id;
1037         __u8 name[32];
1038         __u8 entity[16];
1039         __u8 selector;
1040
1041         __u8 size;
1042         __u8 offset;
1043         __u32 v4l2_type;
1044         __u32 data_type;
1045
1046         compat_caddr_t menu_info;
1047         __u32 menu_count;
1048
1049         __u32 reserved[4];
1050 };
1051
1052 static int uvc_v4l2_get_xu_mapping(struct uvc_xu_control_mapping *kp,
1053                         const struct uvc_xu_control_mapping32 __user *up)
1054 {
1055         struct uvc_menu_info __user *umenus;
1056         struct uvc_menu_info __user *kmenus;
1057         compat_caddr_t p;
1058
1059         if (!access_ok(VERIFY_READ, up, sizeof(*up)) ||
1060             __copy_from_user(kp, up, offsetof(typeof(*up), menu_info)) ||
1061             __get_user(kp->menu_count, &up->menu_count))
1062                 return -EFAULT;
1063
1064         memset(kp->reserved, 0, sizeof(kp->reserved));
1065
1066         if (kp->menu_count == 0) {
1067                 kp->menu_info = NULL;
1068                 return 0;
1069         }
1070
1071         if (__get_user(p, &up->menu_info))
1072                 return -EFAULT;
1073         umenus = compat_ptr(p);
1074         if (!access_ok(VERIFY_READ, umenus, kp->menu_count * sizeof(*umenus)))
1075                 return -EFAULT;
1076
1077         kmenus = compat_alloc_user_space(kp->menu_count * sizeof(*kmenus));
1078         if (kmenus == NULL)
1079                 return -EFAULT;
1080         kp->menu_info = kmenus;
1081
1082         if (copy_in_user(kmenus, umenus, kp->menu_count * sizeof(*umenus)))
1083                 return -EFAULT;
1084
1085         return 0;
1086 }
1087
1088 static int uvc_v4l2_put_xu_mapping(const struct uvc_xu_control_mapping *kp,
1089                         struct uvc_xu_control_mapping32 __user *up)
1090 {
1091         struct uvc_menu_info __user *umenus;
1092         struct uvc_menu_info __user *kmenus = kp->menu_info;
1093         compat_caddr_t p;
1094
1095         if (!access_ok(VERIFY_WRITE, up, sizeof(*up)) ||
1096             __copy_to_user(up, kp, offsetof(typeof(*up), menu_info)) ||
1097             __put_user(kp->menu_count, &up->menu_count))
1098                 return -EFAULT;
1099
1100         __clear_user(up->reserved, sizeof(up->reserved));
1101
1102         if (kp->menu_count == 0)
1103                 return 0;
1104
1105         if (get_user(p, &up->menu_info))
1106                 return -EFAULT;
1107         umenus = compat_ptr(p);
1108         if (!access_ok(VERIFY_WRITE, umenus, kp->menu_count * sizeof(*umenus)))
1109                 return -EFAULT;
1110
1111         if (copy_in_user(umenus, kmenus, kp->menu_count * sizeof(*umenus)))
1112                 return -EFAULT;
1113
1114         return 0;
1115 }
1116
1117 struct uvc_xu_control_query32 {
1118         __u8 unit;
1119         __u8 selector;
1120         __u8 query;
1121         __u16 size;
1122         compat_caddr_t data;
1123 };
1124
1125 static int uvc_v4l2_get_xu_query(struct uvc_xu_control_query *kp,
1126                         const struct uvc_xu_control_query32 __user *up)
1127 {
1128         u8 __user *udata;
1129         u8 __user *kdata;
1130         compat_caddr_t p;
1131
1132         if (!access_ok(VERIFY_READ, up, sizeof(*up)) ||
1133             __copy_from_user(kp, up, offsetof(typeof(*up), data)))
1134                 return -EFAULT;
1135
1136         if (kp->size == 0) {
1137                 kp->data = NULL;
1138                 return 0;
1139         }
1140
1141         if (__get_user(p, &up->data))
1142                 return -EFAULT;
1143         udata = compat_ptr(p);
1144         if (!access_ok(VERIFY_READ, udata, kp->size))
1145                 return -EFAULT;
1146
1147         kdata = compat_alloc_user_space(kp->size);
1148         if (kdata == NULL)
1149                 return -EFAULT;
1150         kp->data = kdata;
1151
1152         if (copy_in_user(kdata, udata, kp->size))
1153                 return -EFAULT;
1154
1155         return 0;
1156 }
1157
1158 static int uvc_v4l2_put_xu_query(const struct uvc_xu_control_query *kp,
1159                         struct uvc_xu_control_query32 __user *up)
1160 {
1161         u8 __user *udata;
1162         u8 __user *kdata = kp->data;
1163         compat_caddr_t p;
1164
1165         if (!access_ok(VERIFY_WRITE, up, sizeof(*up)) ||
1166             __copy_to_user(up, kp, offsetof(typeof(*up), data)))
1167                 return -EFAULT;
1168
1169         if (kp->size == 0)
1170                 return 0;
1171
1172         if (get_user(p, &up->data))
1173                 return -EFAULT;
1174         udata = compat_ptr(p);
1175         if (!access_ok(VERIFY_READ, udata, kp->size))
1176                 return -EFAULT;
1177
1178         if (copy_in_user(udata, kdata, kp->size))
1179                 return -EFAULT;
1180
1181         return 0;
1182 }
1183
1184 #define UVCIOC_CTRL_MAP32       _IOWR('u', 0x20, struct uvc_xu_control_mapping32)
1185 #define UVCIOC_CTRL_QUERY32     _IOWR('u', 0x21, struct uvc_xu_control_query32)
1186
1187 static long uvc_v4l2_compat_ioctl32(struct file *file,
1188                      unsigned int cmd, unsigned long arg)
1189 {
1190         union {
1191                 struct uvc_xu_control_mapping xmap;
1192                 struct uvc_xu_control_query xqry;
1193         } karg;
1194         void __user *up = compat_ptr(arg);
1195         mm_segment_t old_fs;
1196         long ret;
1197
1198         switch (cmd) {
1199         case UVCIOC_CTRL_MAP32:
1200                 cmd = UVCIOC_CTRL_MAP;
1201                 ret = uvc_v4l2_get_xu_mapping(&karg.xmap, up);
1202                 break;
1203
1204         case UVCIOC_CTRL_QUERY32:
1205                 cmd = UVCIOC_CTRL_QUERY;
1206                 ret = uvc_v4l2_get_xu_query(&karg.xqry, up);
1207                 break;
1208
1209         default:
1210                 return -ENOIOCTLCMD;
1211         }
1212
1213         old_fs = get_fs();
1214         set_fs(KERNEL_DS);
1215         ret = uvc_v4l2_ioctl(file, cmd, (unsigned long)&karg);
1216         set_fs(old_fs);
1217
1218         if (ret < 0)
1219                 return ret;
1220
1221         switch (cmd) {
1222         case UVCIOC_CTRL_MAP:
1223                 ret = uvc_v4l2_put_xu_mapping(&karg.xmap, up);
1224                 break;
1225
1226         case UVCIOC_CTRL_QUERY:
1227                 ret = uvc_v4l2_put_xu_query(&karg.xqry, up);
1228                 break;
1229         }
1230
1231         return ret;
1232 }
1233 #endif
1234
1235 static ssize_t uvc_v4l2_read(struct file *file, char __user *data,
1236                     size_t count, loff_t *ppos)
1237 {
1238         uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_read: not implemented.\n");
1239         return -EINVAL;
1240 }
1241
1242 static int uvc_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
1243 {
1244         struct uvc_fh *handle = file->private_data;
1245         struct uvc_streaming *stream = handle->stream;
1246
1247         uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_mmap\n");
1248
1249         return uvc_queue_mmap(&stream->queue, vma);
1250 }
1251
1252 static unsigned int uvc_v4l2_poll(struct file *file, poll_table *wait)
1253 {
1254         struct uvc_fh *handle = file->private_data;
1255         struct uvc_streaming *stream = handle->stream;
1256
1257         uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_poll\n");
1258
1259         return uvc_queue_poll(&stream->queue, file, wait);
1260 }
1261
1262 #ifndef CONFIG_MMU
1263 static unsigned long uvc_v4l2_get_unmapped_area(struct file *file,
1264                 unsigned long addr, unsigned long len, unsigned long pgoff,
1265                 unsigned long flags)
1266 {
1267         struct uvc_fh *handle = file->private_data;
1268         struct uvc_streaming *stream = handle->stream;
1269
1270         uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_get_unmapped_area\n");
1271
1272         return uvc_queue_get_unmapped_area(&stream->queue, pgoff);
1273 }
1274 #endif
1275
1276 const struct v4l2_file_operations uvc_fops = {
1277         .owner          = THIS_MODULE,
1278         .open           = uvc_v4l2_open,
1279         .release        = uvc_v4l2_release,
1280         .unlocked_ioctl = uvc_v4l2_ioctl,
1281 #ifdef CONFIG_COMPAT
1282         .compat_ioctl32 = uvc_v4l2_compat_ioctl32,
1283 #endif
1284         .read           = uvc_v4l2_read,
1285         .mmap           = uvc_v4l2_mmap,
1286         .poll           = uvc_v4l2_poll,
1287 #ifndef CONFIG_MMU
1288         .get_unmapped_area = uvc_v4l2_get_unmapped_area,
1289 #endif
1290 };
1291