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                 ret = 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                 if (ret == 0)
 553                         ctrl->value = xctrl.value;
 554                 break;
 555         }
 556
 557         case VIDIOC_QUERYMENU:
 558                 return uvc_v4l2_query_menu(chain, arg);
 559
 560         case VIDIOC_G_EXT_CTRLS:
 561         {
 562                 struct v4l2_ext_controls *ctrls = arg;
 563                 struct v4l2_ext_control *ctrl = ctrls->controls;
 564                 unsigned int i;
 565
 566                 ret = uvc_ctrl_begin(chain);
 567                 if (ret < 0)
 568                         return ret;
 569
 570                 for (i = 0; i < ctrls->count; ++ctrl, ++i) {
 571                         ret = uvc_ctrl_get(chain, ctrl);
 572                         if (ret < 0) {
 573                                 uvc_ctrl_rollback(chain);
 574                                 ctrls->error_idx = i;
 575                                 return ret;
 576                         }
 577                 }
 578                 ctrls->error_idx = 0;
 579                 ret = uvc_ctrl_rollback(chain);
 580                 break;
 581         }
 582
 583         case VIDIOC_S_EXT_CTRLS:
 584         case VIDIOC_TRY_EXT_CTRLS:
 585         {
 586                 struct v4l2_ext_controls *ctrls = arg;
 587                 struct v4l2_ext_control *ctrl = ctrls->controls;
 588                 unsigned int i;
 589
 590                 ret = uvc_ctrl_begin(chain);
 591                 if (ret < 0)
 592                         return ret;
 593
 594                 for (i = 0; i < ctrls->count; ++ctrl, ++i) {
 595                         ret = uvc_ctrl_set(chain, ctrl);
 596                         if (ret < 0) {
 597                                 uvc_ctrl_rollback(chain);
 598                                 ctrls->error_idx = i;
 599                                 return ret;
 600                         }
 601                 }
 602
 603                 ctrls->error_idx = 0;
 604
 605                 if (cmd == VIDIOC_S_EXT_CTRLS)
 606                         ret = uvc_ctrl_commit(chain);
 607                 else
 608                         ret = uvc_ctrl_rollback(chain);
 609                 break;
 610         }
 611
 612         /* Get, Set & Enum input */
 613         case VIDIOC_ENUMINPUT:
 614         {
 615                 const struct uvc_entity *selector = chain->selector;
 616                 struct v4l2_input *input = arg;
 617                 struct uvc_entity *iterm = NULL;
 618                 u32 index = input->index;
 619                 int pin = 0;
 620
 621                 if (selector == NULL ||
 622                     (chain->dev->quirks & UVC_QUIRK_IGNORE_SELECTOR_UNIT)) {
 623                         if (index != 0)
 624                                 return -EINVAL;
 625                         list_for_each_entry(iterm, &chain->entities, chain) {
 626                                 if (UVC_ENTITY_IS_ITERM(iterm))
 627                                         break;
 628                         }
 629                         pin = iterm->id;
 630                 } else if (pin < selector->bNrInPins) {
 631                         pin = selector->baSourceID[index];
 632                         list_for_each_entry(iterm, &chain->entities, chain) {
 633                                 if (!UVC_ENTITY_IS_ITERM(iterm))
 634                                         continue;
 635                                 if (iterm->id == pin)
 636                                         break;
 637                         }
 638                 }
 639
 640                 if (iterm == NULL || iterm->id != pin)
 641                         return -EINVAL;
 642
 643                 memset(input, 0, sizeof *input);
 644                 input->index = index;
 645                 strlcpy(input->name, iterm->name, sizeof input->name);
 646                 if (UVC_ENTITY_TYPE(iterm) == UVC_ITT_CAMERA)
 647                         input->type = V4L2_INPUT_TYPE_CAMERA;
 648                 break;
 649         }
 650
 651         case VIDIOC_G_INPUT:
 652         {
 653                 u8 input;
 654
 655                 if (chain->selector == NULL ||
 656                     (chain->dev->quirks & UVC_QUIRK_IGNORE_SELECTOR_UNIT)) {
 657                         *(int *)arg = 0;
 658                         break;
 659                 }
 660
 661                 ret = uvc_query_ctrl(chain->dev, UVC_GET_CUR,
 662                         chain->selector->id, chain->dev->intfnum,
 663                         UVC_SU_INPUT_SELECT_CONTROL, &input, 1);
 664                 if (ret < 0)
 665                         return ret;
 666
 667                 *(int *)arg = input - 1;
 668                 break;
 669         }
 670
 671         case VIDIOC_S_INPUT:
 672         {
 673                 u32 input = *(u32 *)arg + 1;
 674
 675                 if ((ret = uvc_acquire_privileges(handle)) < 0)
 676                         return ret;
 677
 678                 if (chain->selector == NULL ||
 679                     (chain->dev->quirks & UVC_QUIRK_IGNORE_SELECTOR_UNIT)) {
 680                         if (input != 1)
 681                                 return -EINVAL;
 682                         break;
 683                 }
 684
 685                 if (input == 0 || input > chain->selector->bNrInPins)
 686                         return -EINVAL;
 687
 688                 return uvc_query_ctrl(chain->dev, UVC_SET_CUR,
 689                         chain->selector->id, chain->dev->intfnum,
 690                         UVC_SU_INPUT_SELECT_CONTROL, &input, 1);
 691         }
 692
 693         /* Try, Get, Set & Enum format */
 694         case VIDIOC_ENUM_FMT:
 695         {
 696                 struct v4l2_fmtdesc *fmt = arg;
 697                 struct uvc_format *format;
 698                 enum v4l2_buf_type type = fmt->type;
 699                 __u32 index = fmt->index;
 700
 701                 if (fmt->type != stream->type ||
 702                     fmt->index >= stream->nformats)
 703                         return -EINVAL;
 704
 705                 memset(fmt, 0, sizeof(*fmt));
 706                 fmt->index = index;
 707                 fmt->type = type;
 708
 709                 format = &stream->format[fmt->index];
 710                 fmt->flags = 0;
 711                 if (format->flags & UVC_FMT_FLAG_COMPRESSED)
 712                         fmt->flags |= V4L2_FMT_FLAG_COMPRESSED;
 713                 strlcpy(fmt->description, format->name,
 714                         sizeof fmt->description);
 715                 fmt->description[sizeof fmt->description - 1] = 0;
 716                 fmt->pixelformat = format->fcc;
 717                 break;
 718         }
 719
 720         case VIDIOC_TRY_FMT:
 721         {
 722                 struct uvc_streaming_control probe;
 723
 724                 return uvc_v4l2_try_format(stream, arg, &probe, NULL, NULL);
 725         }
 726
 727         case VIDIOC_S_FMT:
 728                 if ((ret = uvc_acquire_privileges(handle)) < 0)
 729                         return ret;
 730
 731                 return uvc_v4l2_set_format(stream, arg);
 732
 733         case VIDIOC_G_FMT:
 734                 return uvc_v4l2_get_format(stream, arg);
 735
 736         /* Frame size enumeration */
 737         case VIDIOC_ENUM_FRAMESIZES:
 738         {
 739                 struct v4l2_frmsizeenum *fsize = arg;
 740                 struct uvc_format *format = NULL;
 741                 struct uvc_frame *frame;
 742                 int i;
 743
 744                 /* Look for the given pixel format */
 745                 for (i = 0; i < stream->nformats; i++) {
 746                         if (stream->format[i].fcc ==
 747                                         fsize->pixel_format) {
 748                                 format = &stream->format[i];
 749                                 break;
 750                         }
 751                 }
 752                 if (format == NULL)
 753                         return -EINVAL;
 754
 755                 if (fsize->index >= format->nframes)
 756                         return -EINVAL;
 757
 758                 frame = &format->frame[fsize->index];
 759                 fsize->type = V4L2_FRMSIZE_TYPE_DISCRETE;
 760                 fsize->discrete.width = frame->wWidth;
 761                 fsize->discrete.height = frame->wHeight;
 762                 break;
 763         }
 764
 765         /* Frame interval enumeration */
 766         case VIDIOC_ENUM_FRAMEINTERVALS:
 767         {
 768                 struct v4l2_frmivalenum *fival = arg;
 769                 struct uvc_format *format = NULL;
 770                 struct uvc_frame *frame = NULL;
 771                 int i;
 772
 773                 /* Look for the given pixel format and frame size */
 774                 for (i = 0; i < stream->nformats; i++) {
 775                         if (stream->format[i].fcc ==
 776                                         fival->pixel_format) {
 777                                 format = &stream->format[i];
 778                                 break;
 779                         }
 780                 }
 781                 if (format == NULL)
 782                         return -EINVAL;
 783
 784                 for (i = 0; i < format->nframes; i++) {
 785                         if (format->frame[i].wWidth == fival->width &&
 786                             format->frame[i].wHeight == fival->height) {
 787                                 frame = &format->frame[i];
 788                                 break;
 789                         }
 790                 }
 791                 if (frame == NULL)
 792                         return -EINVAL;
 793
 794                 if (frame->bFrameIntervalType) {
 795                         if (fival->index >= frame->bFrameIntervalType)
 796                                 return -EINVAL;
 797
 798                         fival->type = V4L2_FRMIVAL_TYPE_DISCRETE;
 799                         fival->discrete.numerator =
 800                                 frame->dwFrameInterval[fival->index];
 801                         fival->discrete.denominator = 10000000;
 802                         uvc_simplify_fraction(&fival->discrete.numerator,
 803                                 &fival->discrete.denominator, 8, 333);
 804                 } else {
 805                         fival->type = V4L2_FRMIVAL_TYPE_STEPWISE;
 806                         fival->stepwise.min.numerator =
 807                                 frame->dwFrameInterval[0];
 808                         fival->stepwise.min.denominator = 10000000;
 809                         fival->stepwise.max.numerator =
 810                                 frame->dwFrameInterval[1];
 811                         fival->stepwise.max.denominator = 10000000;
 812                         fival->stepwise.step.numerator =
 813                                 frame->dwFrameInterval[2];
 814                         fival->stepwise.step.denominator = 10000000;
 815                         uvc_simplify_fraction(&fival->stepwise.min.numerator,
 816                                 &fival->stepwise.min.denominator, 8, 333);
 817                         uvc_simplify_fraction(&fival->stepwise.max.numerator,
 818                                 &fival->stepwise.max.denominator, 8, 333);
 819                         uvc_simplify_fraction(&fival->stepwise.step.numerator,
 820                                 &fival->stepwise.step.denominator, 8, 333);
 821                 }
 822                 break;
 823         }
 824
 825         /* Get & Set streaming parameters */
 826         case VIDIOC_G_PARM:
 827                 return uvc_v4l2_get_streamparm(stream, arg);
 828
 829         case VIDIOC_S_PARM:
 830                 if ((ret = uvc_acquire_privileges(handle)) < 0)
 831                         return ret;
 832
 833                 return uvc_v4l2_set_streamparm(stream, arg);
 834
 835         /* Cropping and scaling */
 836         case VIDIOC_CROPCAP:
 837         {
 838                 struct v4l2_cropcap *ccap = arg;
 839                 struct uvc_frame *frame = stream->cur_frame;
 840
 841                 if (ccap->type != stream->type)
 842                         return -EINVAL;
 843
 844                 ccap->bounds.left = 0;
 845                 ccap->bounds.top = 0;
 846                 ccap->bounds.width = frame->wWidth;
 847                 ccap->bounds.height = frame->wHeight;
 848
 849                 ccap->defrect = ccap->bounds;
 850
 851                 ccap->pixelaspect.numerator = 1;
 852                 ccap->pixelaspect.denominator = 1;
 853                 break;
 854         }
 855
 856         case VIDIOC_G_CROP:
 857         case VIDIOC_S_CROP:
 858                 return -EINVAL;
 859
 860         /* Buffers & streaming */
 861         case VIDIOC_REQBUFS:
 862         {
 863                 struct v4l2_requestbuffers *rb = arg;
 864                 unsigned int bufsize =
 865                         stream->ctrl.dwMaxVideoFrameSize;
 866
 867                 if (rb->type != stream->type ||
 868                     rb->memory != V4L2_MEMORY_MMAP)
 869                         return -EINVAL;
 870
 871                 if ((ret = uvc_acquire_privileges(handle)) < 0)
 872                         return ret;
 873
 874                 ret = uvc_alloc_buffers(&stream->queue, rb->count, bufsize);
 875                 if (ret < 0)
 876                         return ret;
 877
 878                 if (ret == 0)
 879                         uvc_dismiss_privileges(handle);
 880
 881                 rb->count = ret;
 882                 ret = 0;
 883                 break;
 884         }
 885
 886         case VIDIOC_QUERYBUF:
 887         {
 888                 struct v4l2_buffer *buf = arg;
 889
 890                 if (buf->type != stream->type)
 891                         return -EINVAL;
 892
 893                 if (!uvc_has_privileges(handle))
 894                         return -EBUSY;
 895
 896                 return uvc_query_buffer(&stream->queue, buf);
 897         }
 898
 899         case VIDIOC_QBUF:
 900                 if (!uvc_has_privileges(handle))
 901                         return -EBUSY;
 902
 903                 return uvc_queue_buffer(&stream->queue, arg);
 904
 905         case VIDIOC_DQBUF:
 906                 if (!uvc_has_privileges(handle))
 907                         return -EBUSY;
 908
 909                 return uvc_dequeue_buffer(&stream->queue, arg,
 910                         file->f_flags & O_NONBLOCK);
 911
 912         case VIDIOC_STREAMON:
 913         {
 914                 int *type = arg;
 915
 916                 if (*type != stream->type)
 917                         return -EINVAL;
 918
 919                 if (!uvc_has_privileges(handle))
 920                         return -EBUSY;
 921
 922                 ret = uvc_video_enable(stream, 1);
 923                 if (ret < 0)
 924                         return ret;
 925                 break;
 926         }
 927
 928         case VIDIOC_STREAMOFF:
 929         {
 930                 int *type = arg;
 931
 932                 if (*type != stream->type)
 933                         return -EINVAL;
 934
 935                 if (!uvc_has_privileges(handle))
 936                         return -EBUSY;
 937
 938                 return uvc_video_enable(stream, 0);
 939         }
 940
 941         /* Analog video standards make no sense for digital cameras. */
 942         case VIDIOC_ENUMSTD:
 943         case VIDIOC_QUERYSTD:
 944         case VIDIOC_G_STD:
 945         case VIDIOC_S_STD:
 946
 947         case VIDIOC_OVERLAY:
 948
 949         case VIDIOC_ENUMAUDIO:
 950         case VIDIOC_ENUMAUDOUT:
 951
 952         case VIDIOC_ENUMOUTPUT:
 953                 uvc_trace(UVC_TRACE_IOCTL, "Unsupported ioctl 0x%08x\n", cmd);
 954                 return -EINVAL;
 955
 956         /* Dynamic controls. */
 957         case UVCIOC_CTRL_ADD:
 958         {
 959                 struct uvc_xu_control_info *xinfo = arg;
 960                 struct uvc_control_info *info;
 961
 962                 if (!capable(CAP_SYS_ADMIN))
 963                         return -EPERM;
 964
 965                 info = kzalloc(sizeof *info, GFP_KERNEL);
 966                 if (info == NULL)
 967                         return -ENOMEM;
 968
 969                 memcpy(info->entity, xinfo->entity, sizeof info->entity);
 970                 info->index = xinfo->index;
 971                 info->selector = xinfo->selector;
 972                 info->size = xinfo->size;
 973                 info->flags = xinfo->flags;
 974
 975                 info->flags |= UVC_CONTROL_GET_MIN | UVC_CONTROL_GET_MAX |
 976                                 UVC_CONTROL_GET_RES | UVC_CONTROL_GET_DEF;
 977
 978                 ret = uvc_ctrl_add_info(info);
 979                 if (ret < 0)
 980                         kfree(info);
 981                 break;
 982         }
 983
 984         case UVCIOC_CTRL_MAP:
 985         {
 986                 struct uvc_xu_control_mapping *xmap = arg;
 987                 struct uvc_control_mapping *map;
 988
 989                 if (!capable(CAP_SYS_ADMIN))
 990                         return -EPERM;
 991
 992                 map = kzalloc(sizeof *map, GFP_KERNEL);
 993                 if (map == NULL)
 994                         return -ENOMEM;
 995
 996                 map->id = xmap->id;
 997                 memcpy(map->name, xmap->name, sizeof map->name);
 998                 memcpy(map->entity, xmap->entity, sizeof map->entity);
 999                 map->selector = xmap->selector;
1000                 map->size = xmap->size;
1001                 map->offset = xmap->offset;
1002                 map->v4l2_type = xmap->v4l2_type;
1003                 map->data_type = xmap->data_type;
1004
1005                 ret = uvc_ctrl_add_mapping(map);
1006                 if (ret < 0)
1007                         kfree(map);
1008                 break;
1009         }
1010
1011         case UVCIOC_CTRL_GET:
1012                 return uvc_xu_ctrl_query(chain, arg, 0);
1013
1014         case UVCIOC_CTRL_SET:
1015                 return uvc_xu_ctrl_query(chain, arg, 1);
1016
1017         default:
1018                 if ((ret = v4l_compat_translate_ioctl(file, cmd, arg,
1019                         uvc_v4l2_do_ioctl)) == -ENOIOCTLCMD)
1020                         uvc_trace(UVC_TRACE_IOCTL, "Unknown ioctl 0x%08x\n",
1021                                   cmd);
1022                 return ret;
1023         }
1024
1025         return ret;
1026 }
1027
1028 static long uvc_v4l2_ioctl(struct file *file,
1029                      unsigned int cmd, unsigned long arg)
1030 {
1031         if (uvc_trace_param & UVC_TRACE_IOCTL) {
1032                 uvc_printk(KERN_DEBUG, "uvc_v4l2_ioctl(");
1033                 v4l_printk_ioctl(cmd);
1034                 printk(")\n");
1035         }
1036
1037         return video_usercopy(file, cmd, arg, uvc_v4l2_do_ioctl);
1038 }
1039
1040 static ssize_t uvc_v4l2_read(struct file *file, char __user *data,
1041                     size_t count, loff_t *ppos)
1042 {
1043         uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_read: not implemented.\n");
1044         return -EINVAL;
1045 }
1046
1047 /*
1048  * VMA operations.
1049  */
1050 static void uvc_vm_open(struct vm_area_struct *vma)
1051 {
1052         struct uvc_buffer *buffer = vma->vm_private_data;
1053         buffer->vma_use_count++;
1054 }
1055
1056 static void uvc_vm_close(struct vm_area_struct *vma)
1057 {
1058         struct uvc_buffer *buffer = vma->vm_private_data;
1059         buffer->vma_use_count--;
1060 }
1061
1062 static const struct vm_operations_struct uvc_vm_ops = {
1063         .open           = uvc_vm_open,
1064         .close          = uvc_vm_close,
1065 };
1066
1067 static int uvc_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
1068 {
1069         struct uvc_fh *handle = (struct uvc_fh *)file->private_data;
1070         struct uvc_streaming *stream = handle->stream;
1071         struct uvc_video_queue *queue = &stream->queue;
1072         struct uvc_buffer *uninitialized_var(buffer);
1073         struct page *page;
1074         unsigned long addr, start, size;
1075         unsigned int i;
1076         int ret = 0;
1077
1078         uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_mmap\n");
1079
1080         start = vma->vm_start;
1081         size = vma->vm_end - vma->vm_start;
1082
1083         mutex_lock(&queue->mutex);
1084
1085         for (i = 0; i < queue->count; ++i) {
1086                 buffer = &queue->buffer[i];
1087                 if ((buffer->buf.m.offset >> PAGE_SHIFT) == vma->vm_pgoff)
1088                         break;
1089         }
1090
1091         if (i == queue->count || size != queue->buf_size) {
1092                 ret = -EINVAL;
1093                 goto done;
1094         }
1095
1096         /*
1097          * VM_IO marks the area as being an mmaped region for I/O to a
1098          * device. It also prevents the region from being core dumped.
1099          */
1100         vma->vm_flags |= VM_IO;
1101
1102         addr = (unsigned long)queue->mem + buffer->buf.m.offset;
1103         while (size > 0) {
1104                 page = vmalloc_to_page((void *)addr);
1105                 if ((ret = vm_insert_page(vma, start, page)) < 0)
1106                         goto done;
1107
1108                 start += PAGE_SIZE;
1109                 addr += PAGE_SIZE;
1110                 size -= PAGE_SIZE;
1111         }
1112
1113         vma->vm_ops = &uvc_vm_ops;
1114         vma->vm_private_data = buffer;
1115         uvc_vm_open(vma);
1116
1117 done:
1118         mutex_unlock(&queue->mutex);
1119         return ret;
1120 }
1121
1122 static unsigned int uvc_v4l2_poll(struct file *file, poll_table *wait)
1123 {
1124         struct uvc_fh *handle = (struct uvc_fh *)file->private_data;
1125         struct uvc_streaming *stream = handle->stream;
1126
1127         uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_poll\n");
1128
1129         return uvc_queue_poll(&stream->queue, file, wait);
1130 }
1131
1132 const struct v4l2_file_operations uvc_fops = {
1133         .owner          = THIS_MODULE,
1134         .open           = uvc_v4l2_open,
1135         .release        = uvc_v4l2_release,
1136         .ioctl          = uvc_v4l2_ioctl,
1137         .read           = uvc_v4l2_read,
1138         .mmap           = uvc_v4l2_mmap,
1139         .poll           = uvc_v4l2_poll,
1140 };
1141