sys/v4l2/v4l2_calls.c

   1 /* G-Streamer generic V4L2 element - generic V4L2 calls handling
   2  * Copyright (C) 2002 Ronald Bultje <rbultje@ronald.bitfreak.net>
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Library General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Library General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Library General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 #ifdef HAVE_CONFIG_H
  21 #include <config.h>
  22 #endif
  23
  24 #include <sys/types.h>
  25 #include <sys/stat.h>
  26 #include <fcntl.h>
  27 #include <sys/ioctl.h>
  28 #include <sys/mman.h>
  29 #include <string.h>
  30 #include <errno.h>
  31 #include <unistd.h>
  32 #include "v4l2_calls.h"
  33 #include "gstv4l2tuner.h"
  34 #include "gstv4l2xoverlay.h"
  35 #include "gstv4l2colorbalance.h"
  36
  37 #include "gstv4l2src.h"
  38
  39 #define DEBUG(format, args...) \
  40         GST_DEBUG_OBJECT (\
  41                 GST_ELEMENT(v4l2element), \
  42                 "V4L2: " format, ##args)
  43
  44
  45 /******************************************************
  46  * gst_v4l2_get_capabilities():
  47  *   get the device's capturing capabilities
  48  * return value: TRUE on success, FALSE on error
  49  ******************************************************/
  50
  51 static gboolean
  52 gst_v4l2_get_capabilities (GstV4l2Element *v4l2element)
  53 {
  54         DEBUG("getting capabilities");
  55         GST_V4L2_CHECK_OPEN(v4l2element);
  56
  57         if (ioctl(v4l2element->video_fd, VIDIOC_QUERYCAP, &(v4l2element->vcap)) < 0) {
  58                 gst_element_error(GST_ELEMENT(v4l2element),
  59                         "Error getting %s capabilities: %s",
  60                         v4l2element->device, g_strerror(errno));
  61                 return FALSE;
  62         }
  63
  64         return TRUE;
  65 }
  66
  67
  68 /******************************************************
  69  * gst_v4l2_empty_lists() and gst_v4l2_fill_lists():
  70  *   fill/empty the lists of enumerations
  71  * return value: TRUE on success, FALSE on error
  72  ******************************************************/
  73
  74 static gboolean
  75 gst_v4l2_fill_lists (GstV4l2Element *v4l2element)
  76 {
  77         gint n;
  78         const GList *pads =
  79                 gst_element_get_pad_list (GST_ELEMENT (v4l2element));
  80         GstPadDirection dir = GST_PAD_UNKNOWN;
  81
  82         DEBUG("getting enumerations");
  83         GST_V4L2_CHECK_OPEN(v4l2element);
  84
  85         /* sinks have outputs, all others have inputs */
  86         if (pads && g_list_length ((GList *) pads) == 1)
  87                 dir = GST_PAD_DIRECTION (GST_PAD (pads->data));
  88
  89         if (dir != GST_PAD_SINK) {
  90         /* and now, the inputs */
  91                 for (n=0;;n++) {
  92                         struct v4l2_input input;
  93                         GstV4l2TunerChannel *v4l2channel;
  94                         GstTunerChannel *channel;
  95
  96                         input.index = n;
  97                         if (ioctl(v4l2element->video_fd, VIDIOC_ENUMINPUT,
  98                                   &input) < 0) {
  99                                 if (errno == EINVAL)
 100                                         break; /* end of enumeration */
 101                                 else {
 102                                         gst_element_error(GST_ELEMENT(v4l2element),
 103                                                 "Failed to get no. %d in input enumeration for %s: %s",
 104                                                 n, v4l2element->device,
 105                                                 g_strerror(errno));
 106                                         return FALSE;
 107                                 }
 108                         }
 109
 110                         v4l2channel =
 111                                 g_object_new(GST_TYPE_V4L2_TUNER_CHANNEL, NULL);
 112                         channel = GST_TUNER_CHANNEL(v4l2channel);
 113                         channel->label = g_strdup(input.name);
 114                         channel->flags = GST_TUNER_CHANNEL_INPUT;
 115                         v4l2channel->index = n;
 116                         if (input.type == V4L2_INPUT_TYPE_TUNER) {
 117                                 struct v4l2_tuner vtun;
 118
 119                                 v4l2channel->tuner = input.tuner;
 120                                 channel->flags |= GST_TUNER_CHANNEL_FREQUENCY;
 121
 122                                 vtun.index = input.tuner;
 123                                 if (ioctl(v4l2element->video_fd, VIDIOC_G_TUNER,
 124                                           &vtun) < 0) {
 125                                         gst_element_error(GST_ELEMENT(v4l2element),
 126                                                 "Failed to get tuner %d settings on %s: %s",
 127                                                 input.tuner,
 128                                                 v4l2element->device,
 129                                                 g_strerror(errno));
 130                                         g_object_unref(G_OBJECT(channel));
 131                                         return FALSE;
 132                                 }
 133                                 channel->min_frequency = vtun.rangelow;
 134                                 channel->max_frequency = vtun.rangehigh;
 135                                 channel->min_signal = 0;
 136                                 channel->max_signal = 0xffff;
 137                         }
 138                         if (input.audioset) {
 139                                 /* we take the first. We don't care for
 140                                  * the others for now */
 141                                 while (!(input.audioset &
 142                                          (1<<v4l2channel->audio)))
 143                                         v4l2channel->audio++;
 144                                 channel->flags |= GST_TUNER_CHANNEL_AUDIO;
 145                         }
 146
 147                         v4l2element->channels =
 148                                 g_list_append(v4l2element->channels,
 149                                               (gpointer) channel);
 150                 }
 151         } else {
 152                 /* outputs */
 153                 for (n=0;;n++) {
 154                         struct v4l2_output output;
 155                         GstV4l2TunerChannel *v4l2channel;
 156                         GstTunerChannel *channel;
 157
 158                         output.index = n;
 159                         if (ioctl(v4l2element->video_fd, VIDIOC_ENUMOUTPUT,
 160                                   &output) < 0) {
 161                                 if (errno == EINVAL)
 162                                         break; /* end of enumeration */
 163                                 else {
 164                                         gst_element_error(GST_ELEMENT(v4l2element),
 165                                                 "Failed to get no. %d in output enumeration for %s: %s",
 166                                                 n, v4l2element->device,
 167                                                 g_strerror(errno));
 168                                         return FALSE;
 169                                 }
 170                         }
 171
 172                         v4l2channel = g_object_new(GST_TYPE_V4L2_TUNER_CHANNEL, NULL);
 173                         channel = GST_TUNER_CHANNEL(v4l2channel);
 174                         channel->label = g_strdup(output.name);
 175                         channel->flags = GST_TUNER_CHANNEL_OUTPUT;
 176                         v4l2channel->index = n;
 177                         if (output.audioset) {
 178                                 /* we take the first. We don't care for
 179                                  * the others for now */
 180                                 while (!(output.audioset &
 181                                          (1<<v4l2channel->audio)))
 182                                         v4l2channel->audio++;
 183                                 channel->flags |= GST_TUNER_CHANNEL_AUDIO;
 184                         }
 185
 186                         v4l2element->channels =
 187                                 g_list_append(v4l2element->channels,
 188                                               (gpointer) channel);
 189                 }
 190         }
 191
 192         /* norms... */
 193         for (n=0;;n++) {
 194                 struct v4l2_standard standard;
 195                 GstV4l2TunerNorm *v4l2norm;
 196                 GstTunerNorm *norm;
 197
 198                 standard.index = n;
 199                 if (ioctl(v4l2element->video_fd, VIDIOC_ENUMSTD, &standard) < 0) {
 200                         if (errno == EINVAL)
 201                                 break; /* end of enumeration */
 202                         else {
 203                                 gst_element_error(GST_ELEMENT(v4l2element),
 204                                         "Failed to get no. %d in norm enumeration for %s: %s",
 205                                         n, v4l2element->device, g_strerror(errno));
 206                                 return FALSE;
 207                         }
 208                 }
 209
 210                 v4l2norm = g_object_new(GST_TYPE_V4L2_TUNER_NORM, NULL);
 211                 norm = GST_TUNER_NORM (v4l2norm);
 212                 norm->label = g_strdup(standard.name);
 213                 norm->fps = (gfloat) standard.frameperiod.denominator /
 214                                 standard.frameperiod.numerator;
 215                 v4l2norm->index = standard.id;
 216
 217                 v4l2element->norms = g_list_append(v4l2element->norms,
 218                                                    (gpointer) norm);
 219         }
 220
 221         /* and lastly, controls+menus (if appropriate) */
 222         for (n=V4L2_CID_BASE;;n++) {
 223                 struct v4l2_queryctrl control;
 224                 GstV4l2ColorBalanceChannel *v4l2channel;
 225                 GstColorBalanceChannel *channel;
 226
 227                 /* hacky... */
 228                 if (n == V4L2_CID_LASTP1)
 229                         n = V4L2_CID_PRIVATE_BASE;
 230
 231                 control.id = n;
 232                 if (ioctl(v4l2element->video_fd, VIDIOC_QUERYCTRL, &control) < 0) {
 233                         if (errno == EINVAL) {
 234                                 if (n < V4L2_CID_PRIVATE_BASE)
 235                                         continue;
 236                                 else
 237                                         break;
 238                         } else {
 239                                 gst_element_error(GST_ELEMENT(v4l2element),
 240                                         "Failed to get no. %d in control enumeration for %s: %s",
 241                                         n, v4l2element->device, g_strerror(errno));
 242                                 return FALSE;
 243                         }
 244                 }
 245                 if (control.flags & V4L2_CTRL_FLAG_DISABLED)
 246                         continue;
 247
 248                 switch (n) {
 249                         case V4L2_CID_BRIGHTNESS:
 250                         case V4L2_CID_CONTRAST:
 251                         case V4L2_CID_SATURATION:
 252                         case V4L2_CID_HUE:
 253                         case V4L2_CID_BLACK_LEVEL:
 254                         case V4L2_CID_AUTO_WHITE_BALANCE:
 255                         case V4L2_CID_DO_WHITE_BALANCE:
 256                         case V4L2_CID_RED_BALANCE:
 257                         case V4L2_CID_BLUE_BALANCE:
 258                         case V4L2_CID_GAMMA:
 259                         case V4L2_CID_EXPOSURE:
 260                         case V4L2_CID_AUTOGAIN:
 261                         case V4L2_CID_GAIN:
 262                                 /* we only handle these for now */
 263                                 break;
 264                         default:
 265                                 DEBUG("ControlID %s (%d) unhandled, FIXME",
 266                                       control.name, n);
 267                                 control.id++;
 268                                 break;
 269                 }
 270                 if (n != control.id)
 271                         continue;
 272
 273                 v4l2channel = g_object_new(GST_TYPE_V4L2_COLOR_BALANCE_CHANNEL,
 274                                            NULL);
 275                 channel = GST_COLOR_BALANCE_CHANNEL(v4l2channel);
 276                 channel->label = g_strdup(control.name);
 277                 v4l2channel->index = n;
 278
 279 #if 0
 280                 if (control.type == V4L2_CTRL_TYPE_MENU) {
 281                         struct v4l2_querymenu menu, *mptr;
 282                         int i;
 283                         menu.id = n;
 284                         for (i=0;;i++) {
 285                                 menu.index = i;
 286                                 if (ioctl(v4l2element->video_fd, VIDIOC_QUERYMENU, &menu) < 0) {
 287                                         if (errno == EINVAL)
 288                                                 break; /* end of enumeration */
 289                                         else {
 290                                                 gst_element_error(GST_ELEMENT(v4l2element),
 291                                                         "Failed to get no. %d in menu %d enumeration for %s: %s",
 292                                                         i, n, v4l2element->device, g_strerror(errno));
 293                                                 return FALSE;
 294                                         }
 295                                 }
 296                                 mptr = g_malloc(sizeof(menu));
 297                                 memcpy(mptr, &menu, sizeof(menu));
 298                                 menus = g_list_append(menus, mptr);
 299                         }
 300                 }
 301                 v4l2element->menus = g_list_append(v4l2element->menus, menus);
 302 #endif
 303
 304                 switch (control.type) {
 305                         case V4L2_CTRL_TYPE_INTEGER:
 306                                 channel->min_value = control.minimum;
 307                                 channel->max_value = control.maximum;
 308                                 break;
 309                         case V4L2_CTRL_TYPE_BOOLEAN:
 310                                 channel->min_value = FALSE;
 311                                 channel->max_value = TRUE;
 312                                 break;
 313                         default:
 314                                 channel->min_value =
 315                                         channel->max_value = 0;
 316                                 break;
 317                 }
 318
 319                 v4l2element->colors = g_list_append(v4l2element->colors,
 320                                                     (gpointer) channel);
 321         }
 322
 323         return TRUE;
 324 }
 325
 326
 327 static void
 328 gst_v4l2_empty_lists (GstV4l2Element *v4l2element)
 329 {
 330         DEBUG("deleting enumerations");
 331
 332         g_list_foreach (v4l2element->channels, (GFunc) g_object_unref, NULL);
 333         g_list_free (v4l2element->channels);
 334         v4l2element->channels = NULL;
 335
 336         g_list_foreach (v4l2element->norms, (GFunc) g_object_unref, NULL);
 337         g_list_free (v4l2element->norms);
 338         v4l2element->norms = NULL;
 339
 340         g_list_foreach (v4l2element->colors, (GFunc) g_object_unref, NULL);
 341         g_list_free (v4l2element->colors);
 342         v4l2element->colors = NULL;
 343 }
 344
 345 /* FIXME: move this stuff to gstv4l2tuner.c? */
 346
 347 static void
 348 gst_v4l2_set_defaults (GstV4l2Element *v4l2element)
 349 {
 350   GstTunerNorm *norm = NULL;
 351   GstTunerChannel *channel = NULL;
 352   GstTuner *tuner = GST_TUNER (v4l2element);
 353
 354   if (v4l2element->norm)
 355     norm = gst_tuner_find_norm_by_name (tuner, v4l2element->norm);
 356   if (norm) {
 357     gst_tuner_set_norm (tuner, norm);
 358   } else {
 359     norm = GST_TUNER_NORM (gst_tuner_get_norm (GST_TUNER (v4l2element)));
 360     v4l2element->norm = g_strdup (norm->label);
 361     gst_tuner_norm_changed (tuner, norm);
 362     g_object_notify (G_OBJECT (v4l2element), "norm");
 363   }
 364
 365   if (v4l2element->channel)
 366     channel = gst_tuner_find_channel_by_name (tuner, v4l2element->channel);
 367   if (channel) {
 368     gst_tuner_set_channel (tuner, channel);
 369   } else {
 370     channel = GST_TUNER_CHANNEL (gst_tuner_get_channel (GST_TUNER (v4l2element)));
 371     v4l2element->channel = g_strdup (channel->label);
 372     gst_tuner_channel_changed (tuner, channel);
 373     g_object_notify (G_OBJECT (v4l2element), "channel");
 374   }
 375   if (v4l2element->frequency != 0) {
 376     gst_tuner_set_frequency (tuner, channel, v4l2element->frequency);
 377   } else {
 378     v4l2element->frequency = gst_tuner_get_frequency (tuner, channel);
 379     if (v4l2element->frequency == 0) {
 380       /* guess */
 381       gst_tuner_set_frequency (tuner, channel, 1000);
 382     } else {
 383       g_object_notify (G_OBJECT (v4l2element), "frequency");
 384     }
 385   }
 386 }
 387
 388
 389 /******************************************************
 390  * gst_v4l2_open():
 391  *   open the video device (v4l2element->device)
 392  * return value: TRUE on success, FALSE on error
 393  ******************************************************/
 394
 395 gboolean
 396 gst_v4l2_open (GstV4l2Element *v4l2element)
 397 {
 398         DEBUG("Trying to open device %s", v4l2element->device);
 399         GST_V4L2_CHECK_NOT_OPEN(v4l2element);
 400         GST_V4L2_CHECK_NOT_ACTIVE(v4l2element);
 401
 402         /* be sure we have a device */
 403         if (!v4l2element->device)
 404                 v4l2element->device = g_strdup("/dev/video");
 405
 406         /* open the device */
 407         v4l2element->video_fd = open(v4l2element->device, O_RDWR);
 408         if (!GST_V4L2_IS_OPEN(v4l2element)) {
 409                 gst_element_error(GST_ELEMENT(v4l2element),
 410                         "Failed to open device %s: %s",
 411                         v4l2element->device, g_strerror(errno));
 412                 goto error;
 413         }
 414
 415         /* get capabilities */
 416         if (!gst_v4l2_get_capabilities(v4l2element)) {
 417                 goto error;
 418         }
 419
 420         /* do we need to be a capture device? */
 421         if (GST_IS_V4L2SRC(v4l2element) &&
 422             !(v4l2element->vcap.capabilities & V4L2_CAP_VIDEO_CAPTURE)) {
 423                 gst_element_error(GST_ELEMENT(v4l2element),
 424                                   "Not a capture device (0x%x)",
 425                                   v4l2element->vcap.capabilities);
 426                 goto error;
 427         }
 428
 429         /* create enumerations */
 430         if (!gst_v4l2_fill_lists(v4l2element))
 431                 goto error;
 432
 433         /* set defaults */
 434         gst_v4l2_set_defaults (v4l2element);
 435
 436         GST_INFO_OBJECT (v4l2element, "Opened device '%s' (%s) successfully\n",
 437                 v4l2element->vcap.card, v4l2element->device);
 438
 439         return TRUE;
 440
 441 error:
 442         if (GST_V4L2_IS_OPEN(v4l2element)) {
 443                 /* close device */
 444                 close(v4l2element->video_fd);
 445                 v4l2element->video_fd = -1;
 446         }
 447         /* empty lists */
 448         gst_v4l2_empty_lists(v4l2element);
 449
 450         return FALSE;
 451 }
 452
 453
 454 /******************************************************
 455  * gst_v4l2_close():
 456  *   close the video device (v4l2element->video_fd)
 457  * return value: TRUE on success, FALSE on error
 458  ******************************************************/
 459
 460 gboolean
 461 gst_v4l2_close (GstV4l2Element *v4l2element)
 462 {
 463         DEBUG("Trying to close %s", v4l2element->device);
 464         GST_V4L2_CHECK_OPEN(v4l2element);
 465         GST_V4L2_CHECK_NOT_ACTIVE(v4l2element);
 466
 467         /* close device */
 468         close(v4l2element->video_fd);
 469         v4l2element->video_fd = -1;
 470
 471         /* empty lists */
 472         gst_v4l2_empty_lists(v4l2element);
 473
 474         return TRUE;
 475 }
 476
 477
 478 /******************************************************
 479  * gst_v4l2_get_norm()
 480  *   Get the norm of the current device
 481  * return value: TRUE on success, FALSE on error
 482  ******************************************************/
 483
 484 gboolean
 485 gst_v4l2_get_norm (GstV4l2Element *v4l2element,
 486                    v4l2_std_id    *norm)
 487 {
 488         DEBUG("getting norm");
 489         GST_V4L2_CHECK_OPEN(v4l2element);
 490
 491         if (ioctl(v4l2element->video_fd, VIDIOC_G_STD, norm) < 0) {
 492                 gst_element_error(GST_ELEMENT(v4l2element),
 493                         "Failed to get the current norm for device %s: %s",
 494                         v4l2element->device, g_strerror(errno));
 495                 return FALSE;
 496         }
 497
 498         return TRUE;
 499 }
 500
 501
 502 /******************************************************
 503  * gst_v4l2_set_norm()
 504  *   Set the norm of the current device
 505  * return value: TRUE on success, FALSE on error
 506  ******************************************************/
 507
 508 gboolean
 509 gst_v4l2_set_norm (GstV4l2Element *v4l2element,
 510                    v4l2_std_id     norm)
 511 {
 512         DEBUG("trying to set norm to %llx", norm);
 513         GST_V4L2_CHECK_OPEN(v4l2element);
 514         GST_V4L2_CHECK_NOT_ACTIVE(v4l2element);
 515
 516         if (ioctl(v4l2element->video_fd, VIDIOC_S_STD, &norm) < 0) {
 517                 gst_element_error(GST_ELEMENT(v4l2element),
 518                         "Failed to set norm 0x%llx for device %s: %s",
 519                         norm, v4l2element->device, g_strerror(errno));
 520                 return FALSE;
 521         }
 522
 523         return TRUE;
 524 }
 525
 526
 527 /******************************************************
 528  * gst_v4l2_get_input()
 529  *   Get the input of the current device
 530  * return value: TRUE on success, FALSE on error
 531  ******************************************************/
 532
 533 gboolean
 534 gst_v4l2_get_input (GstV4l2Element *v4l2element,
 535                     gint           *input)
 536 {
 537         gint n;
 538
 539         DEBUG("trying to get input");
 540         GST_V4L2_CHECK_OPEN(v4l2element);
 541
 542         if (ioctl(v4l2element->video_fd, VIDIOC_G_INPUT, &n) < 0) {
 543                 gst_element_error(GST_ELEMENT(v4l2element),
 544                         "Failed to get current input on device %s: %s",
 545                         v4l2element->device, g_strerror(errno));
 546                 return FALSE;
 547         }
 548
 549         *input = n;
 550
 551         return TRUE;
 552 }
 553
 554
 555 /******************************************************
 556  * gst_v4l2_set_input()
 557  *   Set the input of the current device
 558  * return value: TRUE on success, FALSE on error
 559  ******************************************************/
 560
 561 gboolean
 562 gst_v4l2_set_input (GstV4l2Element *v4l2element,
 563                     gint            input)
 564 {
 565         DEBUG("trying to set input to %d", input);
 566         GST_V4L2_CHECK_OPEN(v4l2element);
 567         GST_V4L2_CHECK_NOT_ACTIVE(v4l2element);
 568
 569         if (ioctl(v4l2element->video_fd, VIDIOC_S_INPUT, &input) < 0) {
 570                 gst_element_error(GST_ELEMENT(v4l2element),
 571                         "Failed to set input %d on device %s: %s",
 572                         input, v4l2element->device, g_strerror(errno));
 573                 return FALSE;
 574         }
 575
 576         return TRUE;
 577 }
 578
 579
 580 /******************************************************
 581  * gst_v4l2_get_output()
 582  *   Get the output of the current device
 583  * return value: TRUE on success, FALSE on error
 584  ******************************************************/
 585
 586 gboolean
 587 gst_v4l2_get_output (GstV4l2Element *v4l2element,
 588                      gint           *output)
 589 {
 590         gint n;
 591
 592         DEBUG("trying to get output");
 593         GST_V4L2_CHECK_OPEN(v4l2element);
 594
 595         if (ioctl(v4l2element->video_fd, VIDIOC_G_OUTPUT, &n) < 0) {
 596                 gst_element_error(GST_ELEMENT(v4l2element),
 597                         "Failed to get current output on device %s: %s",
 598                         v4l2element->device, g_strerror(errno));
 599                 return FALSE;
 600         }
 601
 602         *output = n;
 603
 604         return TRUE;
 605 }
 606
 607
 608 /******************************************************
 609  * gst_v4l2_set_output()
 610  *   Set the output of the current device
 611  * return value: TRUE on success, FALSE on error
 612  ******************************************************/
 613
 614 gboolean
 615 gst_v4l2_set_output (GstV4l2Element *v4l2element,
 616                      gint            output)
 617 {
 618         DEBUG("trying to set output to %d", output);
 619         GST_V4L2_CHECK_OPEN(v4l2element);
 620         GST_V4L2_CHECK_NOT_ACTIVE(v4l2element);
 621
 622         if (ioctl(v4l2element->video_fd, VIDIOC_S_OUTPUT, &output) < 0) {
 623                 gst_element_error(GST_ELEMENT(v4l2element),
 624                         "Failed to set output %d on device %s: %s",
 625                         output, v4l2element->device, g_strerror(errno));
 626                 return FALSE;
 627         }
 628
 629         return TRUE;
 630 }
 631
 632
 633 /******************************************************
 634  * gst_v4l2_get_frequency():
 635  *   get the current frequency
 636  * return value: TRUE on success, FALSE on error
 637  ******************************************************/
 638
 639 gboolean
 640 gst_v4l2_get_frequency (GstV4l2Element *v4l2element,
 641                         gint            tunernum,
 642                         gulong         *frequency)
 643 {
 644         struct v4l2_frequency freq;
 645
 646         DEBUG("getting current tuner frequency");
 647         GST_V4L2_CHECK_OPEN(v4l2element);
 648
 649         freq.tuner = tunernum;
 650         if (ioctl(v4l2element->video_fd, VIDIOC_G_FREQUENCY, &freq) < 0) {
 651                 gst_element_error(GST_ELEMENT(v4l2element),
 652                         "Failed to get current tuner frequency for device %s: %s",
 653                         v4l2element->device, g_strerror(errno));
 654                 return FALSE;
 655         }
 656
 657         *frequency = freq.frequency;
 658
 659         return TRUE;
 660 }
 661
 662
 663 /******************************************************
 664  * gst_v4l2_set_frequency():
 665  *   set frequency
 666  * return value: TRUE on success, FALSE on error
 667  ******************************************************/
 668
 669 gboolean
 670 gst_v4l2_set_frequency (GstV4l2Element *v4l2element,
 671                         gint            tunernum,
 672                         gulong          frequency)
 673 {
 674         struct v4l2_frequency freq;
 675
 676         DEBUG("setting current tuner frequency to %lu", frequency);
 677         GST_V4L2_CHECK_OPEN(v4l2element);
 678         GST_V4L2_CHECK_NOT_ACTIVE(v4l2element);
 679
 680         freq.tuner = tunernum;
 681         /* fill in type - ignore error */
 682         ioctl(v4l2element->video_fd, VIDIOC_G_FREQUENCY, &freq);
 683         freq.frequency = frequency;
 684
 685         if (ioctl(v4l2element->video_fd, VIDIOC_S_FREQUENCY, &freq) < 0) {
 686                 gst_element_error(GST_ELEMENT(v4l2element),
 687                         "Failed to set tuner frequency to %lu for device %s: %s",
 688                         frequency, v4l2element->device, g_strerror(errno));
 689                 return FALSE;
 690         }
 691
 692         return TRUE;
 693 }
 694
 695
 696 /******************************************************
 697  * gst_v4l2_signal_strength():
 698  *   get the strength of the signal on the current input
 699  * return value: TRUE on success, FALSE on error
 700  ******************************************************/
 701
 702 gboolean
 703 gst_v4l2_signal_strength (GstV4l2Element *v4l2element,
 704                           gint            tunernum,
 705                           gulong         *signal_strength)
 706 {
 707         struct v4l2_tuner tuner;
 708
 709         DEBUG("trying to get signal strength");
 710         GST_V4L2_CHECK_OPEN(v4l2element);
 711
 712         tuner.index = tunernum;
 713         if (ioctl(v4l2element->video_fd, VIDIOC_G_TUNER, &tuner) < 0) {
 714                 gst_element_error(GST_ELEMENT(v4l2element),
 715                         "Failed to get signal strength for device %s: %s",
 716                         v4l2element->device, g_strerror(errno));
 717                 return FALSE;
 718         }
 719
 720         *signal_strength = tuner.signal;
 721
 722         return TRUE;
 723 }
 724
 725
 726 /******************************************************
 727  * gst_v4l2_get_attribute():
 728  *   try to get the value of one specific attribute
 729  * return value: TRUE on success, FALSE on error
 730  ******************************************************/
 731
 732 gboolean
 733 gst_v4l2_get_attribute  (GstV4l2Element *v4l2element,
 734                          int             attribute_num,
 735                          int            *value)
 736 {
 737         struct v4l2_control control;
 738
 739         GST_V4L2_CHECK_OPEN(v4l2element);
 740
 741         DEBUG("getting value of attribute %d", attribute_num);
 742
 743         control.id = attribute_num;
 744
 745         if (ioctl(v4l2element->video_fd, VIDIOC_G_CTRL, &control) < 0) {
 746                 gst_element_error(GST_ELEMENT(v4l2element),
 747                         "Failed to get value for control %d on device %s: %s",
 748                         attribute_num, v4l2element->device, g_strerror(errno));
 749                 return FALSE;
 750         }
 751
 752         *value = control.value;
 753
 754         return TRUE;
 755 }
 756
 757
 758 /******************************************************
 759  * gst_v4l2_set_attribute():
 760  *   try to set the value of one specific attribute
 761  * return value: TRUE on success, FALSE on error
 762  ******************************************************/
 763
 764 gboolean
 765 gst_v4l2_set_attribute  (GstV4l2Element *v4l2element,
 766                          int             attribute_num,
 767                          const int       value)
 768 {
 769         struct v4l2_control control;
 770
 771         GST_V4L2_CHECK_OPEN(v4l2element);
 772
 773         DEBUG("setting value of attribute %d to %d", attribute_num, value);
 774
 775         control.id = attribute_num;
 776         control.value = value;
 777
 778         if (ioctl(v4l2element->video_fd, VIDIOC_S_CTRL, &control) < 0) {
 779                 gst_element_error(GST_ELEMENT(v4l2element),
 780                         "Failed to set value %d for control %d on device %s: %s",
 781                         value, attribute_num, v4l2element->device, g_strerror(errno));
 782                 return FALSE;
 783         }
 784
 785         return TRUE;
 786 }
 787