drivers/media/video/uvc/uvc_v4l2.c

   1 /*
   2  *      uvc_v4l2.c  --  USB Video Class driver - V4L2 API
   3  *
   4  *      Copyright (C) 2005-2009
   5  *          Laurent Pinchart (laurent.pinchart@skynet.be)
   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/usb.h>
  19 #include <linux/videodev2.h>
  20 #include <linux/vmalloc.h>
  21 #include <linux/mm.h>
  22 #include <linux/wait.h>
  23 #include <asm/atomic.h>
  24
  25 #include <media/v4l2-common.h>
  26 #include <media/v4l2-ioctl.h>
  27
  28 #include "uvcvideo.h"
  29
  30 /* ------------------------------------------------------------------------
  31  * V4L2 interface
  32  */
  33
  34 /*
  35  * Mapping V4L2 controls to UVC controls can be straighforward if done well.
  36  * Most of the UVC controls exist in V4L2, and can be mapped directly. Some
  37  * must be grouped (for instance the Red Balance, Blue Balance and Do White
  38  * Balance V4L2 controls use the White Balance Component UVC control) or
  39  * otherwise translated. The approach we take here is to use a translation
  40  * table for the controls that can be mapped directly, and handle the others
  41  * manually.
  42  */
  43 static int uvc_v4l2_query_menu(struct uvc_video_chain *chain,
  44         struct v4l2_querymenu *query_menu)
  45 {
  46         struct uvc_menu_info *menu_info;
  47         struct uvc_control_mapping *mapping;
  48         struct uvc_control *ctrl;
  49         u32 index = query_menu->index;
  50         u32 id = query_menu->id;
  51
  52         ctrl = uvc_find_control(chain, query_menu->id, &mapping);
  53         if (ctrl == NULL || mapping->v4l2_type != V4L2_CTRL_TYPE_MENU)
  54                 return -EINVAL;
  55
  56         if (query_menu->index >= mapping->menu_count)
  57                 return -EINVAL;
  58
  59         memset(query_menu, 0, sizeof(*query_menu));
  60         query_menu->id = id;
  61         query_menu->index = index;
  62
  63         menu_info = &mapping->menu_info[query_menu->index];
  64         strlcpy(query_menu->name, menu_info->name, sizeof query_menu->name);
  65         return 0;
  66 }
  67
  68 /*
  69  * Find the frame interval closest to the requested frame interval for the
  70  * given frame format and size. This should be done by the device as part of
  71  * the Video Probe and Commit negotiation, but some hardware don't implement
  72  * that feature.
  73  */
  74 static __u32 uvc_try_frame_interval(struct uvc_frame *frame, __u32 interval)
  75 {
  76         unsigned int i;
  77
  78         if (frame->bFrameIntervalType) {
  79                 __u32 best = -1, dist;
  80
  81                 for (i = 0; i < frame->bFrameIntervalType; ++i) {
  82                         dist = interval > frame->dwFrameInterval[i]
  83                              ? interval - frame->dwFrameInterval[i]
  84                              : frame->dwFrameInterval[i] - interval;
  85
  86                         if (dist > best)
  87                                 break;
  88
  89                         best = dist;
  90                 }
  91
  92                 interval = frame->dwFrameInterval[i-1];
  93         } else {
  94                 const __u32 min = frame->dwFrameInterval[0];
  95                 const __u32 max = frame->dwFrameInterval[1];
  96                 const __u32 step = frame->dwFrameInterval[2];
  97
  98                 interval = min + (interval - min + step/2) / step * step;
  99                 if (interval > max)
 100                         interval = max;
 101         }
 102
 103         return interval;
 104 }
 105
 106 static int uvc_v4l2_try_format(struct uvc_streaming *stream,
 107         struct v4l2_format *fmt, struct uvc_streaming_control *probe,
 108         struct uvc_format **uvc_format, struct uvc_frame **uvc_frame)
 109 {
 110         struct uvc_format *format = NULL;
 111         struct uvc_frame *frame = NULL;
 112         __u16 rw, rh;
 113         unsigned int d, maxd;
 114         unsigned int i;
 115         __u32 interval;
 116         int ret = 0;
 117         __u8 *fcc;
 118
 119         if (fmt->type != stream->type)
 120                 return -EINVAL;
 121
 122         fcc = (__u8 *)&fmt->fmt.pix.pixelformat;
 123         uvc_trace(UVC_TRACE_FORMAT, "Trying format 0x%08x (%c%c%c%c): %ux%u.\n",
 124                         fmt->fmt.pix.pixelformat,
 125                         fcc[0], fcc[1], fcc[2], fcc[3],
 126                         fmt->fmt.pix.width, fmt->fmt.pix.height);
 127
 128         /* Check if the hardware supports the requested format. */
 129         for (i = 0; i < stream->nformats; ++i) {
 130                 format = &stream->format[i];
 131                 if (format->fcc == fmt->fmt.pix.pixelformat)
 132                         break;
 133         }
 134
 135         if (format == NULL || format->fcc != fmt->fmt.pix.pixelformat) {
 136                 uvc_trace(UVC_TRACE_FORMAT, "Unsupported format 0x%08x.\n",
 137                                 fmt->fmt.pix.pixelformat);
 138                 return -EINVAL;
 139         }
 140
 141         /* Find the closest image size. The distance between image sizes is
 142          * the size in pixels of the non-overlapping regions between the
 143          * requested size and the frame-specified size.
 144          */
 145         rw = fmt->fmt.pix.width;
 146         rh = fmt->fmt.pix.height;
 147         maxd = (unsigned int)-1;
 148
 149         for (i = 0; i < format->nframes; ++i) {
 150                 __u16 w = format->frame[i].wWidth;
 151                 __u16 h = format->frame[i].wHeight;
 152
 153                 d = min(w, rw) * min(h, rh);
 154                 d = w*h + rw*rh - 2*d;
 155                 if (d < maxd) {
 156                         maxd = d;
 157                         frame = &format->frame[i];
 158                 }
 159
 160                 if (maxd == 0)
 161                         break;
 162         }
 163
 164         if (frame == NULL) {
 165                 uvc_trace(UVC_TRACE_FORMAT, "Unsupported size %ux%u.\n",
 166                                 fmt->fmt.pix.width, fmt->fmt.pix.height);
 167                 return -EINVAL;
 168         }
 169
 170         /* Use the default frame interval. */
 171         interval = frame->dwDefaultFrameInterval;
 172         uvc_trace(UVC_TRACE_FORMAT, "Using default frame interval %u.%u us "
 173                 "(%u.%u fps).\n", interval/10, interval%10, 10000000/interval,
 174                 (100000000/interval)%10);
 175
 176         /* Set the format index, frame index and frame interval. */
 177         memset(probe, 0, sizeof *probe);
 178         probe->bmHint = 1;      /* dwFrameInterval */
 179         probe->bFormatIndex = format->index;
 180         probe->bFrameIndex = frame->bFrameIndex;
 181         probe->dwFrameInterval = uvc_try_frame_interval(frame, interval);
 182         /* Some webcams stall the probe control set request when the
 183          * dwMaxVideoFrameSize field is set to zero. The UVC specification
 184          * clearly states that the field is read-only from the host, so this
 185          * is a webcam bug. Set dwMaxVideoFrameSize to the value reported by
 186          * the webcam to work around the problem.
 187          *
 188          * The workaround could probably be enabled for all webcams, so the
 189          * quirk can be removed if needed. It's currently useful to detect
 190          * webcam bugs and fix them before they hit the market (providing
 191          * developers test their webcams with the Linux driver as well as with
 192          * the Windows driver).
 193          */
 194         if (stream->dev->quirks & UVC_QUIRK_PROBE_EXTRAFIELDS)
 195                 probe->dwMaxVideoFrameSize =
 196                         stream->ctrl.dwMaxVideoFrameSize;
 197
 198         /* Probe the device. */
 199         ret = uvc_probe_video(stream, probe);
 200         if (ret < 0)
 201                 goto done;
 202
 203         fmt->fmt.pix.width = frame->wWidth;
 204         fmt->fmt.pix.height = frame->wHeight;
 205         fmt->fmt.pix.field = V4L2_FIELD_NONE;
 206         fmt->fmt.pix.bytesperline = format->bpp * frame->wWidth / 8;
 207         fmt->fmt.pix.sizeimage = probe->dwMaxVideoFrameSize;
 208         fmt->fmt.pix.colorspace = format->colorspace;
 209         fmt->fmt.pix.priv = 0;
 210
 211         if (uvc_format != NULL)
 212                 *uvc_format = format;
 213         if (uvc_frame != NULL)
 214                 *uvc_frame = frame;
 215
 216 done:
 217         return ret;
 218 }
 219
 220 static int uvc_v4l2_get_format(struct uvc_streaming *stream,
 221         struct v4l2_format *fmt)
 222 {
 223         struct uvc_format *format = stream->cur_format;
 224         struct uvc_frame *frame = stream->cur_frame;
 225
 226         if (fmt->type != stream->type)
 227                 return -EINVAL;
 228
 229         if (format == NULL || frame == NULL)
 230                 return -EINVAL;
 231
 232         fmt->fmt.pix.pixelformat = format->fcc;
 233         fmt->fmt.pix.width = frame->wWidth;
 234         fmt->fmt.pix.height = frame->wHeight;
 235         fmt->fmt.pix.field = V4L2_FIELD_NONE;
 236         fmt->fmt.pix.bytesperline = format->bpp * frame->wWidth / 8;
 237         fmt->fmt.pix.sizeimage = stream->ctrl.dwMaxVideoFrameSize;
 238         fmt->fmt.pix.colorspace = format->colorspace;
 239         fmt->fmt.pix.priv = 0;
 240
 241         return 0;
 242 }
 243
 244 static int uvc_v4l2_set_format(struct uvc_streaming *stream,
 245         struct v4l2_format *fmt)
 246 {
 247         struct uvc_streaming_control probe;
 248         struct uvc_format *format;
 249         struct uvc_frame *frame;
 250         int ret;
 251
 252         if (fmt->type != stream->type)
 253                 return -EINVAL;
 254
 255         if (uvc_queue_allocated(&stream->queue))
 256                 return -EBUSY;
 257
 258         ret = uvc_v4l2_try_format(stream, fmt, &probe, &format, &frame);
 259         if (ret < 0)
 260                 return ret;
 261
 262         memcpy(&stream->ctrl, &probe, sizeof probe);
 263         stream->cur_format = format;
 264         stream->cur_frame = frame;
 265
 266         return 0;
 267 }
 268
 269 static int uvc_v4l2_get_streamparm(struct uvc_streaming *stream,
 270                 struct v4l2_streamparm *parm)
 271 {
 272         uint32_t numerator, denominator;
 273
 274         if (parm->type != stream->type)
 275                 return -EINVAL;
 276
 277         numerator = stream->ctrl.dwFrameInterval;
 278         denominator = 10000000;
 279         uvc_simplify_fraction(&numerator, &denominator, 8, 333);
 280
 281         memset(parm, 0, sizeof *parm);
 282         parm->type = stream->type;
 283
 284         if (stream->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
 285                 parm->parm.capture.capability = V4L2_CAP_TIMEPERFRAME;
 286                 parm->parm.capture.capturemode = 0;
 287                 parm->parm.capture.timeperframe.numerator = numerator;
 288                 parm->parm.capture.timeperframe.denominator = denominator;
 289                 parm->parm.capture.extendedmode = 0;
 290                 parm->parm.capture.readbuffers = 0;
 291         } else {
 292                 parm->parm.output.capability = V4L2_CAP_TIMEPERFRAME;
 293                 parm->parm.output.outputmode = 0;
 294                 parm->parm.output.timeperframe.numerator = numerator;
 295                 parm->parm.output.timeperframe.denominator = denominator;
 296         }
 297
 298         return 0;
 299 }
 300
 301 static int uvc_v4l2_set_streamparm(struct uvc_streaming *stream,
 302                 struct v4l2_streamparm *parm)
 303 {
 304         struct uvc_frame *frame = stream->cur_frame;
 305         struct uvc_streaming_control probe;
 306         struct v4l2_fract timeperframe;
 307         uint32_t interval;
 308         int ret;
 309
 310         if (parm->type != stream->type)
 311                 return -EINVAL;
 312
 313         if (uvc_queue_streaming(&stream->queue))
 314                 return -EBUSY;
 315
 316         if (parm->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
 317                 timeperframe = parm->parm.capture.timeperframe;
 318         else
 319                 timeperframe = parm->parm.output.timeperframe;
 320
 321         memcpy(&probe, &stream->ctrl, sizeof probe);
 322         interval = uvc_fraction_to_interval(timeperframe.numerator,
 323                 timeperframe.denominator);
 324
 325         uvc_trace(UVC_TRACE_FORMAT, "Setting frame interval to %u/%u (%u).\n",
 326                 timeperframe.numerator, timeperframe.denominator, interval);
 327         probe.dwFrameInterval = uvc_try_frame_interval(frame, interval);
 328
 329         /* Probe the device with the new settings. */
 330         ret = uvc_probe_video(stream, &probe);
 331         if (ret < 0)
 332                 return ret;
 333
 334         memcpy(&stream->ctrl, &probe, sizeof probe);
 335
 336         /* Return the actual frame period. */
 337         timeperframe.numerator = probe.dwFrameInterval;
 338         timeperframe.denominator = 10000000;
 339         uvc_simplify_fraction(&timeperframe.numerator,
 340                 &timeperframe.denominator, 8, 333);
 341
 342         if (parm->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
 343                 parm->parm.capture.timeperframe = timeperframe;
 344         else
 345                 parm->parm.output.timeperframe = timeperframe;
 346
 347         return 0;
 348 }
 349
 350 /* ------------------------------------------------------------------------
 351  * Privilege management
 352  */
 353
 354 /*
 355  * Privilege management is the multiple-open implementation basis. The current
 356  * implementation is completely transparent for the end-user and doesn't
 357  * require explicit use of the VIDIOC_G_PRIORITY and VIDIOC_S_PRIORITY ioctls.
 358  * Those ioctls enable finer control on the device (by making possible for a
 359  * user to request exclusive access to a device), but are not mature yet.
 360  * Switching to the V4L2 priority mechanism might be considered in the future
 361  * if this situation changes.
 362  *
 363  * Each open instance of a UVC device can either be in a privileged or
 364  * unprivileged state. Only a single instance can be in a privileged state at
 365  * a given time. Trying to perform an operation that requires privileges will
 366  * automatically acquire the required privileges if possible, or return -EBUSY
 367  * otherwise. Privileges are dismissed when closing the instance or when
 368  * freeing the video buffers using VIDIOC_REQBUFS.
 369  *
 370  * Operations that require privileges are:
 371  *
 372  * - VIDIOC_S_INPUT
 373  * - VIDIOC_S_PARM
 374  * - VIDIOC_S_FMT
 375  * - VIDIOC_REQBUFS
 376  */
 377 static int uvc_acquire_privileges(struct uvc_fh *handle)
 378 {
 379         /* Always succeed if the handle is already privileged. */
 380         if (handle->state == UVC_HANDLE_ACTIVE)
 381                 return 0;
 382
 383         /* Check if the device already has a privileged handle. */
 384         if (atomic_inc_return(&handle->stream->active) != 1) {
 385                 atomic_dec(&handle->stream->active);
 386                 return -EBUSY;
 387         }
 388
 389         handle->state = UVC_HANDLE_ACTIVE;
 390         return 0;
 391 }
 392
 393 static void uvc_dismiss_privileges(struct uvc_fh *handle)
 394 {
 395         if (handle->state == UVC_HANDLE_ACTIVE)
 396                 atomic_dec(&handle->stream->active);
 397
 398         handle->state = UVC_HANDLE_PASSIVE;
 399 }
 400
 401 static int uvc_has_privileges(struct uvc_fh *handle)
 402 {
 403         return handle->state == UVC_HANDLE_ACTIVE;
 404 }
 405
 406 /* ------------------------------------------------------------------------
 407  * V4L2 file operations
 408  */
 409
 410 static int uvc_v4l2_open(struct file *file)
 411 {
 412         struct uvc_streaming *stream;
 413         struct uvc_fh *handle;
 414         int ret = 0;
 415
 416         uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_open\n");
 417         stream = video_drvdata(file);
 418
 419         if (stream->dev->state & UVC_DEV_DISCONNECTED)
 420                 return -ENODEV;
 421
 422         ret = usb_autopm_get_interface(stream->dev->intf);
 423         if (ret < 0)
 424                 return ret;
 425
 426         /* Create the device handle. */
 427         handle = kzalloc(sizeof *handle, GFP_KERNEL);
 428         if (handle == NULL) {
 429                 usb_autopm_put_interface(stream->dev->intf);
 430                 return -ENOMEM;
 431         }
 432
 433         if (atomic_inc_return(&stream->dev->users) == 1) {
 434                 ret = uvc_status_start(stream->dev);
 435                 if (ret < 0) {
 436                         usb_autopm_put_interface(stream->dev->intf);
 437                         atomic_dec(&stream->dev->users);
 438                         kfree(handle);
 439                         return ret;
 440                 }
 441         }
 442
 443         handle->chain = stream->chain;
 444         handle->stream = stream;
 445         handle->state = UVC_HANDLE_PASSIVE;
 446         file->private_data = handle;
 447
 448         return 0;
 449 }
 450
 451 static int uvc_v4l2_release(struct file *file)
 452 {
 453         struct uvc_fh *handle = (struct uvc_fh *)file->private_data;
 454         struct uvc_streaming *stream = handle->stream;
 455
 456         uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_release\n");
 457
 458         /* Only free resources if this is a privileged handle. */
 459         if (uvc_has_privileges(handle)) {
 460                 uvc_video_enable(stream, 0);
 461
 462                 mutex_lock(&stream->queue.mutex);
 463                 if (uvc_free_buffers(&stream->queue) < 0)
 464                         uvc_printk(KERN_ERR, "uvc_v4l2_release: Unable to "
 465                                         "free buffers.\n");
 466                 mutex_unlock(&stream->queue.mutex);
 467         }
 468
 469         /* Release the file handle. */
 470         uvc_dismiss_privileges(handle);
 471         kfree(handle);
 472         file->private_data = NULL;
 473
 474         if (atomic_dec_return(&stream->dev->users) == 0)
 475                 uvc_status_stop(stream->dev);
 476
 477         usb_autopm_put_interface(stream->dev->intf);
 478         return 0;
 479 }
 480
 481 static long uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 482 {
 483         struct video_device *vdev = video_devdata(file);
 484         struct uvc_fh *handle = (struct uvc_fh *)file->private_data;
 485         struct uvc_video_chain *chain = handle->chain;
 486         struct uvc_streaming *stream = handle->stream;
 487         long ret = 0;
 488
 489         switch (cmd) {
 490         /* Query capabilities */
 491         case VIDIOC_QUERYCAP:
 492         {
 493                 struct v4l2_capability *cap = arg;
 494
 495                 memset(cap, 0, sizeof *cap);
 496                 strlcpy(cap->driver, "uvcvideo", sizeof cap->driver);
 497                 strlcpy(cap->card, vdev->name, sizeof cap->card);
 498                 usb_make_path(stream->dev->udev,
 499                               cap->bus_info, sizeof(cap->bus_info));
 500                 cap->version = DRIVER_VERSION_NUMBER;
 501                 if (stream->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
 502                         cap->capabilities = V4L2_CAP_VIDEO_CAPTURE
 503                                           | V4L2_CAP_STREAMING;
 504                 else
 505                         cap->capabilities = V4L2_CAP_VIDEO_OUTPUT
 506                                           | V4L2_CAP_STREAMING;
 507                 break;
 508         }
 509
 510         /* Get, Set & Query control */
 511         case VIDIOC_QUERYCTRL:
 512                 return uvc_query_v4l2_ctrl(chain, arg);
 513
 514         case VIDIOC_G_CTRL:
 515         {
 516                 struct v4l2_control *ctrl = arg;
 517                 struct v4l2_ext_control xctrl;
 518
 519                 memset(&xctrl, 0, sizeof xctrl);
 520                 xctrl.id = ctrl->id;
 521
 522                 ret = uvc_ctrl_begin(chain);
 523                 if (ret < 0)
 524                         return ret;
 525
 526                 ret = uvc_ctrl_get(chain, &xctrl);
 527                 uvc_ctrl_rollback(chain);
 528                 if (ret >= 0)
 529                         ctrl->value = xctrl.value;
 530                 break;
 531         }
 532
 533         case VIDIOC_S_CTRL:
 534         {
 535                 struct v4l2_control *ctrl = arg;
 536                 struct v4l2_ext_control xctrl;
 537
 538                 memset(&xctrl, 0, sizeof xctrl);
 539                 xctrl.id = ctrl->id;
 540                 xctrl.value = ctrl->value;
 541
 542                 uvc_ctrl_begin(chain);
 543                 if (ret < 0)
 544                         return ret;
 545
 546                 ret = uvc_ctrl_set(chain, &xctrl);
 547                 if (ret < 0) {
 548                         uvc_ctrl_rollback(chain);
 549                         return ret;
 550                 }
 551                 ret = uvc_ctrl_commit(chain);
 552                 break;
 553         }
 554
 555         case VIDIOC_QUERYMENU:
 556                 return uvc_v4l2_query_menu(chain, arg);
 557
 558         case VIDIOC_G_EXT_CTRLS:
 559         {
 560                 struct v4l2_ext_controls *ctrls = arg;
 561                 struct v4l2_ext_control *ctrl = ctrls->controls;
 562                 unsigned int i;
 563
 564                 ret = uvc_ctrl_begin(chain);
 565                 if (ret < 0)
 566                         return ret;
 567
 568                 for (i = 0; i < ctrls->count; ++ctrl, ++i) {
 569                         ret = uvc_ctrl_get(chain, ctrl);
 570                         if (ret < 0) {
 571                                 uvc_ctrl_rollback(chain);
 572                                 ctrls->error_idx = i;
 573                                 return ret;
 574                         }
 575                 }
 576                 ctrls->error_idx = 0;
 577                 ret = uvc_ctrl_rollback(chain);
 578                 break;
 579         }
 580
 581         case VIDIOC_S_EXT_CTRLS:
 582         case VIDIOC_TRY_EXT_CTRLS:
 583         {
 584                 struct v4l2_ext_controls *ctrls = arg;
 585                 struct v4l2_ext_control *ctrl = ctrls->controls;
 586                 unsigned int i;
 587
 588                 ret = uvc_ctrl_begin(chain);
 589                 if (ret < 0)
 590                         return ret;
 591
 592                 for (i = 0; i < ctrls->count; ++ctrl, ++i) {
 593                         ret = uvc_ctrl_set(chain, ctrl);
 594                         if (ret < 0) {
 595                                 uvc_ctrl_rollback(chain);
 596                                 ctrls->error_idx = i;
 597                                 return ret;
 598                         }
 599                 }
 600
 601                 ctrls->error_idx = 0;
 602
 603                 if (cmd == VIDIOC_S_EXT_CTRLS)
 604                         ret = uvc_ctrl_commit(chain);
 605                 else
 606                         ret = uvc_ctrl_rollback(chain);
 607                 break;
 608         }
 609
 610         /* Get, Set & Enum input */
 611         case VIDIOC_ENUMINPUT:
 612         {
 613                 const struct uvc_entity *selector = chain->selector;
 614                 struct v4l2_input *input = arg;
 615                 struct uvc_entity *iterm = NULL;
 616                 u32 index = input->index;
 617                 int pin = 0;
 618
 619                 if (selector == NULL ||
 620                     (chain->dev->quirks & UVC_QUIRK_IGNORE_SELECTOR_UNIT)) {
 621                         if (index != 0)
 622                                 return -EINVAL;
 623                         list_for_each_entry(iterm, &chain->entities, chain) {
 624                                 if (UVC_ENTITY_IS_ITERM(iterm))
 625                                         break;
 626                         }
 627                         pin = iterm->id;
 628                 } else if (pin < selector->bNrInPins) {
 629                         pin = selector->baSourceID[index];
 630                         list_for_each_entry(iterm, &chain->entities, chain) {
 631                                 if (!UVC_ENTITY_IS_ITERM(iterm))
 632                                         continue;
 633                                 if (iterm->id == pin)
 634                                         break;
 635                         }
 636                 }
 637
 638                 if (iterm == NULL || iterm->id != pin)
 639                         return -EINVAL;
 640
 641                 memset(input, 0, sizeof *input);
 642                 input->index = index;
 643                 strlcpy(input->name, iterm->name, sizeof input->name);
 644                 if (UVC_ENTITY_TYPE(iterm) == UVC_ITT_CAMERA)
 645                         input->type = V4L2_INPUT_TYPE_CAMERA;
 646                 break;
 647         }
 648
 649         case VIDIOC_G_INPUT:
 650         {
 651                 u8 input;
 652
 653                 if (chain->selector == NULL ||
 654                     (chain->dev->quirks & UVC_QUIRK_IGNORE_SELECTOR_UNIT)) {
 655                         *(int *)arg = 0;
 656                         break;
 657                 }
 658
 659                 ret = uvc_query_ctrl(chain->dev, UVC_GET_CUR,
 660                         chain->selector->id, chain->dev->intfnum,
 661                         UVC_SU_INPUT_SELECT_CONTROL, &input, 1);
 662                 if (ret < 0)
 663                         return ret;
 664
 665                 *(int *)arg = input - 1;
 666                 break;
 667         }
 668
 669         case VIDIOC_S_INPUT:
 670         {
 671                 u32 input = *(u32 *)arg + 1;
 672
 673                 if ((ret = uvc_acquire_privileges(handle)) < 0)
 674                         return ret;
 675
 676                 if (chain->selector == NULL ||
 677                     (chain->dev->quirks & UVC_QUIRK_IGNORE_SELECTOR_UNIT)) {
 678                         if (input != 1)
 679                                 return -EINVAL;
 680                         break;
 681                 }
 682
 683                 if (input == 0 || input > chain->selector->bNrInPins)
 684                         return -EINVAL;
 685
 686                 return uvc_query_ctrl(chain->dev, UVC_SET_CUR,
 687                         chain->selector->id, chain->dev->intfnum,
 688                         UVC_SU_INPUT_SELECT_CONTROL, &input, 1);
 689         }
 690
 691         /* Try, Get, Set & Enum format */
 692         case VIDIOC_ENUM_FMT:
 693         {
 694                 struct v4l2_fmtdesc *fmt = arg;
 695                 struct uvc_format *format;
 696                 enum v4l2_buf_type type = fmt->type;
 697                 __u32 index = fmt->index;
 698
 699                 if (fmt->type != stream->type ||
 700                     fmt->index >= stream->nformats)
 701                         return -EINVAL;
 702
 703                 memset(fmt, 0, sizeof(*fmt));
 704                 fmt->index = index;
 705                 fmt->type = type;
 706
 707                 format = &stream->format[fmt->index];
 708                 fmt->flags = 0;
 709                 if (format->flags & UVC_FMT_FLAG_COMPRESSED)
 710                         fmt->flags |= V4L2_FMT_FLAG_COMPRESSED;
 711                 strlcpy(fmt->description, format->name,
 712                         sizeof fmt->description);
 713                 fmt->description[sizeof fmt->description - 1] = 0;
 714                 fmt->pixelformat = format->fcc;
 715                 break;
 716         }
 717
 718         case VIDIOC_TRY_FMT:
 719         {
 720                 struct uvc_streaming_control probe;
 721
 722                 return uvc_v4l2_try_format(stream, arg, &probe, NULL, NULL);
 723         }
 724
 725         case VIDIOC_S_FMT:
 726                 if ((ret = uvc_acquire_privileges(handle)) < 0)
 727                         return ret;
 728
 729                 return uvc_v4l2_set_format(stream, arg);
 730
 731         case VIDIOC_G_FMT:
 732                 return uvc_v4l2_get_format(stream, arg);
 733
 734         /* Frame size enumeration */
 735         case VIDIOC_ENUM_FRAMESIZES:
 736         {
 737                 struct v4l2_frmsizeenum *fsize = arg;
 738                 struct uvc_format *format = NULL;
 739                 struct uvc_frame *frame;
 740                 int i;
 741
 742                 /* Look for the given pixel format */
 743                 for (i = 0; i < stream->nformats; i++) {
 744                         if (stream->format[i].fcc ==
 745                                         fsize->pixel_format) {
 746                                 format = &stream->format[i];
 747                                 break;
 748                         }
 749                 }
 750                 if (format == NULL)
 751                         return -EINVAL;
 752
 753                 if (fsize->index >= format->nframes)
 754                         return -EINVAL;
 755
 756                 frame = &format->frame[fsize->index];
 757                 fsize->type = V4L2_FRMSIZE_TYPE_DISCRETE;
 758                 fsize->discrete.width = frame->wWidth;
 759                 fsize->discrete.height = frame->wHeight;
 760                 break;
 761         }
 762
 763         /* Frame interval enumeration */
 764         case VIDIOC_ENUM_FRAMEINTERVALS:
 765         {
 766                 struct v4l2_frmivalenum *fival = arg;
 767                 struct uvc_format *format = NULL;
 768                 struct uvc_frame *frame = NULL;
 769                 int i;
 770
 771                 /* Look for the given pixel format and frame size */
 772                 for (i = 0; i < stream->nformats; i++) {
 773                         if (stream->format[i].fcc ==
 774                                         fival->pixel_format) {
 775                                 format = &stream->format[i];
 776                                 break;
 777                         }
 778                 }
 779                 if (format == NULL)
 780                         return -EINVAL;
 781
 782                 for (i = 0; i < format->nframes; i++) {
 783                         if (format->frame[i].wWidth == fival->width &&
 784                             format->frame[i].wHeight == fival->height) {
 785                                 frame = &format->frame[i];
 786                                 break;
 787                         }
 788                 }
 789                 if (frame == NULL)
 790                         return -EINVAL;
 791
 792                 if (frame->bFrameIntervalType) {
 793                         if (fival->index >= frame->bFrameIntervalType)
 794                                 return -EINVAL;
 795
 796                         fival->type = V4L2_FRMIVAL_TYPE_DISCRETE;
 797                         fival->discrete.numerator =
 798                                 frame->dwFrameInterval[fival->index];
 799                         fival->discrete.denominator = 10000000;
 800                         uvc_simplify_fraction(&fival->discrete.numerator,
 801                                 &fival->discrete.denominator, 8, 333);
 802                 } else {
 803                         fival->type = V4L2_FRMIVAL_TYPE_STEPWISE;
 804                         fival->stepwise.min.numerator =
 805                                 frame->dwFrameInterval[0];
 806                         fival->stepwise.min.denominator = 10000000;
 807                         fival->stepwise.max.numerator =
 808                                 frame->dwFrameInterval[1];
 809                         fival->stepwise.max.denominator = 10000000;
 810                         fival->stepwise.step.numerator =
 811                                 frame->dwFrameInterval[2];
 812                         fival->stepwise.step.denominator = 10000000;
 813                         uvc_simplify_fraction(&fival->stepwise.min.numerator,
 814                                 &fival->stepwise.min.denominator, 8, 333);
 815                         uvc_simplify_fraction(&fival->stepwise.max.numerator,
 816                                 &fival->stepwise.max.denominator, 8, 333);
 817                         uvc_simplify_fraction(&fival->stepwise.step.numerator,
 818                                 &fival->stepwise.step.denominator, 8, 333);
 819                 }
 820                 break;
 821         }
 822
 823         /* Get & Set streaming parameters */
 824         case VIDIOC_G_PARM:
 825                 return uvc_v4l2_get_streamparm(stream, arg);
 826
 827         case VIDIOC_S_PARM:
 828                 if ((ret = uvc_acquire_privileges(handle)) < 0)
 829                         return ret;
 830
 831                 return uvc_v4l2_set_streamparm(stream, arg);
 832
 833         /* Cropping and scaling */
 834         case VIDIOC_CROPCAP:
 835         {
 836                 struct v4l2_cropcap *ccap = arg;
 837                 struct uvc_frame *frame = stream->cur_frame;
 838
 839                 if (ccap->type != stream->type)
 840                         return -EINVAL;
 841
 842                 ccap->bounds.left = 0;
 843                 ccap->bounds.top = 0;
 844                 ccap->bounds.width = frame->wWidth;
 845                 ccap->bounds.height = frame->wHeight;
 846
 847                 ccap->defrect = ccap->bounds;
 848
 849                 ccap->pixelaspect.numerator = 1;
 850                 ccap->pixelaspect.denominator = 1;
 851                 break;
 852         }
 853
 854         case VIDIOC_G_CROP:
 855         case VIDIOC_S_CROP:
 856                 return -EINVAL;
 857
 858         /* Buffers & streaming */
 859         case VIDIOC_REQBUFS:
 860         {
 861                 struct v4l2_requestbuffers *rb = arg;
 862                 unsigned int bufsize =
 863                         stream->ctrl.dwMaxVideoFrameSize;
 864
 865                 if (rb->type != stream->type ||
 866                     rb->memory != V4L2_MEMORY_MMAP)
 867                         return -EINVAL;
 868
 869                 if ((ret = uvc_acquire_privileges(handle)) < 0)
 870                         return ret;
 871
 872                 ret = uvc_alloc_buffers(&stream->queue, rb->count, bufsize);
 873                 if (ret < 0)
 874                         return ret;
 875
 876                 if (ret == 0)
 877                         uvc_dismiss_privileges(handle);
 878
 879                 rb->count = ret;
 880                 ret = 0;
 881                 break;
 882         }
 883
 884         case VIDIOC_QUERYBUF:
 885         {
 886                 struct v4l2_buffer *buf = arg;
 887
 888                 if (buf->type != stream->type)
 889                         return -EINVAL;
 890
 891                 if (!uvc_has_privileges(handle))
 892                         return -EBUSY;
 893
 894                 return uvc_query_buffer(&stream->queue, buf);
 895         }
 896
 897         case VIDIOC_QBUF:
 898                 if (!uvc_has_privileges(handle))
 899                         return -EBUSY;
 900
 901                 return uvc_queue_buffer(&stream->queue, arg);
 902
 903         case VIDIOC_DQBUF:
 904                 if (!uvc_has_privileges(handle))
 905                         return -EBUSY;
 906
 907                 return uvc_dequeue_buffer(&stream->queue, arg,
 908                         file->f_flags & O_NONBLOCK);
 909
 910         case VIDIOC_STREAMON:
 911         {
 912                 int *type = arg;
 913
 914                 if (*type != stream->type)
 915                         return -EINVAL;
 916
 917                 if (!uvc_has_privileges(handle))
 918                         return -EBUSY;
 919
 920                 ret = uvc_video_enable(stream, 1);
 921                 if (ret < 0)
 922                         return ret;
 923                 break;
 924         }
 925
 926         case VIDIOC_STREAMOFF:
 927         {
 928                 int *type = arg;
 929
 930                 if (*type != stream->type)
 931                         return -EINVAL;
 932
 933                 if (!uvc_has_privileges(handle))
 934                         return -EBUSY;
 935
 936                 return uvc_video_enable(stream, 0);
 937         }
 938
 939         /* Analog video standards make no sense for digital cameras. */
 940         case VIDIOC_ENUMSTD:
 941         case VIDIOC_QUERYSTD:
 942         case VIDIOC_G_STD:
 943         case VIDIOC_S_STD:
 944
 945         case VIDIOC_OVERLAY:
 946
 947         case VIDIOC_ENUMAUDIO:
 948         case VIDIOC_ENUMAUDOUT:
 949
 950         case VIDIOC_ENUMOUTPUT:
 951                 uvc_trace(UVC_TRACE_IOCTL, "Unsupported ioctl 0x%08x\n", cmd);
 952                 return -EINVAL;
 953
 954         /* Dynamic controls. */
 955         case UVCIOC_CTRL_ADD:
 956         {
 957                 struct uvc_xu_control_info *xinfo = arg;
 958                 struct uvc_control_info *info;
 959
 960                 if (!capable(CAP_SYS_ADMIN))
 961                         return -EPERM;
 962
 963                 info = kzalloc(sizeof *info, GFP_KERNEL);
 964                 if (info == NULL)
 965                         return -ENOMEM;
 966
 967                 memcpy(info->entity, xinfo->entity, sizeof info->entity);
 968                 info->index = xinfo->index;
 969                 info->selector = xinfo->selector;
 970                 info->size = xinfo->size;
 971                 info->flags = xinfo->flags;
 972
 973                 info->flags |= UVC_CONTROL_GET_MIN | UVC_CONTROL_GET_MAX |
 974                                 UVC_CONTROL_GET_RES | UVC_CONTROL_GET_DEF;
 975
 976                 ret = uvc_ctrl_add_info(info);
 977                 if (ret < 0)
 978                         kfree(info);
 979                 break;
 980         }
 981
 982         case UVCIOC_CTRL_MAP:
 983         {
 984                 struct uvc_xu_control_mapping *xmap = arg;
 985                 struct uvc_control_mapping *map;
 986
 987                 if (!capable(CAP_SYS_ADMIN))
 988                         return -EPERM;
 989
 990                 map = kzalloc(sizeof *map, GFP_KERNEL);
 991                 if (map == NULL)
 992                         return -ENOMEM;
 993
 994                 map->id = xmap->id;
 995                 memcpy(map->name, xmap->name, sizeof map->name);
 996                 memcpy(map->entity, xmap->entity, sizeof map->entity);
 997                 map->selector = xmap->selector;
 998                 map->size = xmap->size;
 999                 map->offset = xmap->offset;
1000                 map->v4l2_type = xmap->v4l2_type;
1001                 map->data_type = xmap->data_type;
1002
1003                 ret = uvc_ctrl_add_mapping(map);
1004                 if (ret < 0)
1005                         kfree(map);
1006                 break;
1007         }
1008
1009         case UVCIOC_CTRL_GET:
1010                 return uvc_xu_ctrl_query(chain, arg, 0);
1011
1012         case UVCIOC_CTRL_SET:
1013                 return uvc_xu_ctrl_query(chain, arg, 1);
1014
1015         default:
1016                 if ((ret = v4l_compat_translate_ioctl(file, cmd, arg,
1017                         uvc_v4l2_do_ioctl)) == -ENOIOCTLCMD)
1018                         uvc_trace(UVC_TRACE_IOCTL, "Unknown ioctl 0x%08x\n",
1019                                   cmd);
1020                 return ret;
1021         }
1022
1023         return ret;
1024 }
1025
1026 static long uvc_v4l2_ioctl(struct file *file,
1027                      unsigned int cmd, unsigned long arg)
1028 {
1029         if (uvc_trace_param & UVC_TRACE_IOCTL) {
1030                 uvc_printk(KERN_DEBUG, "uvc_v4l2_ioctl(");
1031                 v4l_printk_ioctl(cmd);
1032                 printk(")\n");
1033         }
1034
1035         return video_usercopy(file, cmd, arg, uvc_v4l2_do_ioctl);
1036 }
1037
1038 static ssize_t uvc_v4l2_read(struct file *file, char __user *data,
1039                     size_t count, loff_t *ppos)
1040 {
1041         uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_read: not implemented.\n");
1042         return -EINVAL;
1043 }
1044
1045 /*
1046  * VMA operations.
1047  */
1048 static void uvc_vm_open(struct vm_area_struct *vma)
1049 {
1050         struct uvc_buffer *buffer = vma->vm_private_data;
1051         buffer->vma_use_count++;
1052 }
1053
1054 static void uvc_vm_close(struct vm_area_struct *vma)
1055 {
1056         struct uvc_buffer *buffer = vma->vm_private_data;
1057         buffer->vma_use_count--;
1058 }
1059
1060 static const struct vm_operations_struct uvc_vm_ops = {
1061         .open           = uvc_vm_open,
1062         .close          = uvc_vm_close,
1063 };
1064
1065 static int uvc_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
1066 {
1067         struct uvc_fh *handle = (struct uvc_fh *)file->private_data;
1068         struct uvc_streaming *stream = handle->stream;
1069         struct uvc_video_queue *queue = &stream->queue;
1070         struct uvc_buffer *uninitialized_var(buffer);
1071         struct page *page;
1072         unsigned long addr, start, size;
1073         unsigned int i;
1074         int ret = 0;
1075
1076         uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_mmap\n");
1077
1078         start = vma->vm_start;
1079         size = vma->vm_end - vma->vm_start;
1080
1081         mutex_lock(&queue->mutex);
1082
1083         for (i = 0; i < queue->count; ++i) {
1084                 buffer = &queue->buffer[i];
1085                 if ((buffer->buf.m.offset >> PAGE_SHIFT) == vma->vm_pgoff)
1086                         break;
1087         }
1088
1089         if (i == queue->count || size != queue->buf_size) {
1090                 ret = -EINVAL;
1091                 goto done;
1092         }
1093
1094         /*
1095          * VM_IO marks the area as being an mmaped region for I/O to a
1096          * device. It also prevents the region from being core dumped.
1097          */
1098         vma->vm_flags |= VM_IO;
1099
1100         addr = (unsigned long)queue->mem + buffer->buf.m.offset;
1101         while (size > 0) {
1102                 page = vmalloc_to_page((void *)addr);
1103                 if ((ret = vm_insert_page(vma, start, page)) < 0)
1104                         goto done;
1105
1106                 start += PAGE_SIZE;
1107                 addr += PAGE_SIZE;
1108                 size -= PAGE_SIZE;
1109         }
1110
1111         vma->vm_ops = &uvc_vm_ops;
1112         vma->vm_private_data = buffer;
1113         uvc_vm_open(vma);
1114
1115 done:
1116         mutex_unlock(&queue->mutex);
1117         return ret;
1118 }
1119
1120 static unsigned int uvc_v4l2_poll(struct file *file, poll_table *wait)
1121 {
1122         struct uvc_fh *handle = (struct uvc_fh *)file->private_data;
1123         struct uvc_streaming *stream = handle->stream;
1124
1125         uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_poll\n");
1126
1127         return uvc_queue_poll(&stream->queue, file, wait);
1128 }
1129
1130 const struct v4l2_file_operations uvc_fops = {
1131         .owner          = THIS_MODULE,
1132         .open           = uvc_v4l2_open,
1133         .release        = uvc_v4l2_release,
1134         .ioctl          = uvc_v4l2_ioctl,
1135         .read           = uvc_v4l2_read,
1136         .mmap           = uvc_v4l2_mmap,
1137         .poll           = uvc_v4l2_poll,
1138 };
1139