git.oblomov.eu Git - linux-2.6/blob - drivers/media/video/cx18/cx18-streams.c

   1 /*
   2  *  cx18 init/start/stop/exit stream functions
   3  *
   4  *  Derived from ivtv-streams.c
   5  *
   6  *  Copyright (C) 2007  Hans Verkuil <hverkuil@xs4all.nl>
   7  *
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License as published by
  10  *  the Free Software Foundation; either version 2 of the License, or
  11  *  (at your option) any later version.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to the Free Software
  20  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  21  *  02111-1307  USA
  22  */
  23
  24 #include "cx18-driver.h"
  25 #include "cx18-fileops.h"
  26 #include "cx18-mailbox.h"
  27 #include "cx18-i2c.h"
  28 #include "cx18-queue.h"
  29 #include "cx18-ioctl.h"
  30 #include "cx18-streams.h"
  31 #include "cx18-cards.h"
  32 #include "cx18-scb.h"
  33 #include "cx18-av-core.h"
  34 #include "cx18-dvb.h"
  35
  36 #define CX18_DSP0_INTERRUPT_MASK        0xd0004C
  37
  38 static struct file_operations cx18_v4l2_enc_fops = {
  39       .owner = THIS_MODULE,
  40       .read = cx18_v4l2_read,
  41       .open = cx18_v4l2_open,
  42       .ioctl = cx18_v4l2_ioctl,
  43       .release = cx18_v4l2_close,
  44       .poll = cx18_v4l2_enc_poll,
  45 };
  46
  47 /* offset from 0 to register ts v4l2 minors on */
  48 #define CX18_V4L2_ENC_TS_OFFSET   16
  49 /* offset from 0 to register pcm v4l2 minors on */
  50 #define CX18_V4L2_ENC_PCM_OFFSET  24
  51 /* offset from 0 to register yuv v4l2 minors on */
  52 #define CX18_V4L2_ENC_YUV_OFFSET  32
  53
  54 static struct {
  55         const char *name;
  56         int vfl_type;
  57         int minor_offset;
  58         int dma;
  59         enum v4l2_buf_type buf_type;
  60         struct file_operations *fops;
  61 } cx18_stream_info[] = {
  62         {       /* CX18_ENC_STREAM_TYPE_MPG */
  63                 "encoder MPEG",
  64                 VFL_TYPE_GRABBER, 0,
  65                 PCI_DMA_FROMDEVICE, V4L2_BUF_TYPE_VIDEO_CAPTURE,
  66                 &cx18_v4l2_enc_fops
  67         },
  68         {       /* CX18_ENC_STREAM_TYPE_TS */
  69                 "TS",
  70                 VFL_TYPE_GRABBER, -1,
  71                 PCI_DMA_FROMDEVICE, V4L2_BUF_TYPE_VIDEO_CAPTURE,
  72                 &cx18_v4l2_enc_fops
  73         },
  74         {       /* CX18_ENC_STREAM_TYPE_YUV */
  75                 "encoder YUV",
  76                 VFL_TYPE_GRABBER, CX18_V4L2_ENC_YUV_OFFSET,
  77                 PCI_DMA_FROMDEVICE, V4L2_BUF_TYPE_VIDEO_CAPTURE,
  78                 &cx18_v4l2_enc_fops
  79         },
  80         {       /* CX18_ENC_STREAM_TYPE_VBI */
  81                 "encoder VBI",
  82                 VFL_TYPE_VBI, 0,
  83                 PCI_DMA_FROMDEVICE, V4L2_BUF_TYPE_VBI_CAPTURE,
  84                 &cx18_v4l2_enc_fops
  85         },
  86         {       /* CX18_ENC_STREAM_TYPE_PCM */
  87                 "encoder PCM audio",
  88                 VFL_TYPE_GRABBER, CX18_V4L2_ENC_PCM_OFFSET,
  89                 PCI_DMA_FROMDEVICE, V4L2_BUF_TYPE_PRIVATE,
  90                 &cx18_v4l2_enc_fops
  91         },
  92         {       /* CX18_ENC_STREAM_TYPE_IDX */
  93                 "encoder IDX",
  94                 VFL_TYPE_GRABBER, -1,
  95                 PCI_DMA_FROMDEVICE, V4L2_BUF_TYPE_VIDEO_CAPTURE,
  96                 &cx18_v4l2_enc_fops
  97         },
  98         {       /* CX18_ENC_STREAM_TYPE_RAD */
  99                 "encoder radio",
 100                 VFL_TYPE_RADIO, 0,
 101                 PCI_DMA_NONE, V4L2_BUF_TYPE_PRIVATE,
 102                 &cx18_v4l2_enc_fops
 103         },
 104 };
 105
 106 static void cx18_stream_init(struct cx18 *cx, int type)
 107 {
 108         struct cx18_stream *s = &cx->streams[type];
 109         struct video_device *dev = s->v4l2dev;
 110         u32 max_size = cx->options.megabytes[type] * 1024 * 1024;
 111
 112         /* we need to keep v4l2dev, so restore it afterwards */
 113         memset(s, 0, sizeof(*s));
 114         s->v4l2dev = dev;
 115
 116         /* initialize cx18_stream fields */
 117         s->cx = cx;
 118         s->type = type;
 119         s->name = cx18_stream_info[type].name;
 120         s->handle = 0xffffffff;
 121
 122         s->dma = cx18_stream_info[type].dma;
 123         s->buf_size = cx->stream_buf_size[type];
 124         if (s->buf_size)
 125                 s->buffers = max_size / s->buf_size;
 126         if (s->buffers > 63) {
 127                 /* Each stream has a maximum of 63 buffers,
 128                    ensure we do not exceed that. */
 129                 s->buffers = 63;
 130                 s->buf_size = (max_size / s->buffers) & ~0xfff;
 131         }
 132         spin_lock_init(&s->qlock);
 133         init_waitqueue_head(&s->waitq);
 134         s->id = -1;
 135         cx18_queue_init(&s->q_free);
 136         cx18_queue_init(&s->q_full);
 137         cx18_queue_init(&s->q_io);
 138 }
 139
 140 static int cx18_prep_dev(struct cx18 *cx, int type)
 141 {
 142         struct cx18_stream *s = &cx->streams[type];
 143         u32 cap = cx->v4l2_cap;
 144         int minor_offset = cx18_stream_info[type].minor_offset;
 145         int minor;
 146
 147         /* These four fields are always initialized. If v4l2dev == NULL, then
 148            this stream is not in use. In that case no other fields but these
 149            four can be used. */
 150         s->v4l2dev = NULL;
 151         s->cx = cx;
 152         s->type = type;
 153         s->name = cx18_stream_info[type].name;
 154
 155         /* Check whether the radio is supported */
 156         if (type == CX18_ENC_STREAM_TYPE_RAD && !(cap & V4L2_CAP_RADIO))
 157                 return 0;
 158
 159         /* Check whether VBI is supported */
 160         if (type == CX18_ENC_STREAM_TYPE_VBI &&
 161             !(cap & (V4L2_CAP_VBI_CAPTURE | V4L2_CAP_SLICED_VBI_CAPTURE)))
 162                 return 0;
 163
 164         /* card number + user defined offset + device offset */
 165         minor = cx->num + cx18_first_minor + minor_offset;
 166
 167         /* User explicitly selected 0 buffers for these streams, so don't
 168            create them. */
 169         if (cx18_stream_info[type].dma != PCI_DMA_NONE &&
 170             cx->options.megabytes[type] == 0) {
 171                 CX18_INFO("Disabled %s device\n", cx18_stream_info[type].name);
 172                 return 0;
 173         }
 174
 175         cx18_stream_init(cx, type);
 176
 177         if (minor_offset == -1)
 178                 return 0;
 179
 180         /* allocate and initialize the v4l2 video device structure */
 181         s->v4l2dev = video_device_alloc();
 182         if (s->v4l2dev == NULL) {
 183                 CX18_ERR("Couldn't allocate v4l2 video_device for %s\n",
 184                                 s->name);
 185                 return -ENOMEM;
 186         }
 187
 188         s->v4l2dev->type =
 189                 VID_TYPE_CAPTURE | VID_TYPE_TUNER | VID_TYPE_TELETEXT |
 190                 VID_TYPE_CLIPPING | VID_TYPE_SCALES | VID_TYPE_MPEG_ENCODER;
 191         snprintf(s->v4l2dev->name, sizeof(s->v4l2dev->name), "cx18%d %s",
 192                         cx->num, s->name);
 193
 194         s->v4l2dev->minor = minor;
 195         s->v4l2dev->dev = &cx->dev->dev;
 196         s->v4l2dev->fops = cx18_stream_info[type].fops;
 197         s->v4l2dev->release = video_device_release;
 198
 199         return 0;
 200 }
 201
 202 /* Initialize v4l2 variables and register v4l2 devices */
 203 int cx18_streams_setup(struct cx18 *cx)
 204 {
 205         int type;
 206
 207         /* Setup V4L2 Devices */
 208         for (type = 0; type < CX18_MAX_STREAMS; type++) {
 209                 /* Prepare device */
 210                 if (cx18_prep_dev(cx, type))
 211                         break;
 212
 213                 /* Allocate Stream */
 214                 if (cx18_stream_alloc(&cx->streams[type]))
 215                         break;
 216         }
 217         if (type == CX18_MAX_STREAMS)
 218                 return 0;
 219
 220         /* One or more streams could not be initialized. Clean 'em all up. */
 221         cx18_streams_cleanup(cx, 0);
 222         return -ENOMEM;
 223 }
 224
 225 static int cx18_reg_dev(struct cx18 *cx, int type)
 226 {
 227         struct cx18_stream *s = &cx->streams[type];
 228         int vfl_type = cx18_stream_info[type].vfl_type;
 229         int minor;
 230
 231         /* TODO: Shouldn't this be a VFL_TYPE_TRANSPORT or something?
 232          * We need a VFL_TYPE_TS defined.
 233          */
 234         if (strcmp("TS", s->name) == 0) {
 235                 /* just return if no DVB is supported */
 236                 if ((cx->card->hw_all & CX18_HW_DVB) == 0)
 237                         return 0;
 238                 if (cx18_dvb_register(s) < 0) {
 239                         CX18_ERR("DVB failed to register\n");
 240                         return -EINVAL;
 241                 }
 242         }
 243
 244         if (s->v4l2dev == NULL)
 245                 return 0;
 246
 247         minor = s->v4l2dev->minor;
 248
 249         /* Register device. First try the desired minor, then any free one. */
 250         if (video_register_device(s->v4l2dev, vfl_type, minor) &&
 251                         video_register_device(s->v4l2dev, vfl_type, -1)) {
 252                 CX18_ERR("Couldn't register v4l2 device for %s minor %d\n",
 253                         s->name, minor);
 254                 video_device_release(s->v4l2dev);
 255                 s->v4l2dev = NULL;
 256                 return -ENOMEM;
 257         }
 258         minor = s->v4l2dev->minor;
 259
 260         switch (vfl_type) {
 261         case VFL_TYPE_GRABBER:
 262                 CX18_INFO("Registered device video%d for %s (%d MB)\n",
 263                         minor, s->name, cx->options.megabytes[type]);
 264                 break;
 265
 266         case VFL_TYPE_RADIO:
 267                 CX18_INFO("Registered device radio%d for %s\n",
 268                         minor - MINOR_VFL_TYPE_RADIO_MIN, s->name);
 269                 break;
 270
 271         case VFL_TYPE_VBI:
 272                 if (cx->options.megabytes[type])
 273                         CX18_INFO("Registered device vbi%d for %s (%d MB)\n",
 274                                 minor - MINOR_VFL_TYPE_VBI_MIN,
 275                                 s->name, cx->options.megabytes[type]);
 276                 else
 277                         CX18_INFO("Registered device vbi%d for %s\n",
 278                                 minor - MINOR_VFL_TYPE_VBI_MIN, s->name);
 279                 break;
 280         }
 281
 282         return 0;
 283 }
 284
 285 /* Register v4l2 devices */
 286 int cx18_streams_register(struct cx18 *cx)
 287 {
 288         int type;
 289         int err = 0;
 290
 291         /* Register V4L2 devices */
 292         for (type = 0; type < CX18_MAX_STREAMS; type++)
 293                 err |= cx18_reg_dev(cx, type);
 294
 295         if (err == 0)
 296                 return 0;
 297
 298         /* One or more streams could not be initialized. Clean 'em all up. */
 299         cx18_streams_cleanup(cx, 1);
 300         return -ENOMEM;
 301 }
 302
 303 /* Unregister v4l2 devices */
 304 void cx18_streams_cleanup(struct cx18 *cx, int unregister)
 305 {
 306         struct video_device *vdev;
 307         int type;
 308
 309         /* Teardown all streams */
 310         for (type = 0; type < CX18_MAX_STREAMS; type++) {
 311                 if (cx->streams[type].dvb.enabled)
 312                         cx18_dvb_unregister(&cx->streams[type]);
 313
 314                 vdev = cx->streams[type].v4l2dev;
 315
 316                 cx->streams[type].v4l2dev = NULL;
 317                 if (vdev == NULL)
 318                         continue;
 319
 320                 cx18_stream_free(&cx->streams[type]);
 321
 322                 /* Unregister or release device */
 323                 if (unregister)
 324                         video_unregister_device(vdev);
 325                 else
 326                         video_device_release(vdev);
 327         }
 328 }
 329
 330 static void cx18_vbi_setup(struct cx18_stream *s)
 331 {
 332         struct cx18 *cx = s->cx;
 333         int raw = cx->vbi.sliced_in->service_set == 0;
 334         u32 data[CX2341X_MBOX_MAX_DATA];
 335         int lines;
 336
 337         if (cx->is_60hz) {
 338                 cx->vbi.count = 12;
 339                 cx->vbi.start[0] = 10;
 340                 cx->vbi.start[1] = 273;
 341         } else {        /* PAL/SECAM */
 342                 cx->vbi.count = 18;
 343                 cx->vbi.start[0] = 6;
 344                 cx->vbi.start[1] = 318;
 345         }
 346
 347         /* setup VBI registers */
 348         cx18_av_cmd(cx, VIDIOC_S_FMT, &cx->vbi.in);
 349
 350         /* determine number of lines and total number of VBI bytes.
 351            A raw line takes 1443 bytes: 2 * 720 + 4 byte frame header - 1
 352            The '- 1' byte is probably an unused U or V byte. Or something...
 353            A sliced line takes 51 bytes: 4 byte frame header, 4 byte internal
 354            header, 42 data bytes + checksum (to be confirmed) */
 355         if (raw) {
 356                 lines = cx->vbi.count * 2;
 357         } else {
 358                 lines = cx->is_60hz ? 24 : 38;
 359                 if (cx->is_60hz)
 360                         lines += 2;
 361         }
 362
 363         cx->vbi.enc_size = lines *
 364                 (raw ? cx->vbi.raw_size : cx->vbi.sliced_size);
 365
 366         data[0] = s->handle;
 367         /* Lines per field */
 368         data[1] = (lines / 2) | ((lines / 2) << 16);
 369         /* bytes per line */
 370         data[2] = (raw ? cx->vbi.raw_size : cx->vbi.sliced_size);
 371         /* Every X number of frames a VBI interrupt arrives
 372            (frames as in 25 or 30 fps) */
 373         data[3] = 1;
 374         /* Setup VBI for the cx25840 digitizer */
 375         if (raw) {
 376                 data[4] = 0x20602060;
 377                 data[5] = 0x30703070;
 378         } else {
 379                 data[4] = 0xB0F0B0F0;
 380                 data[5] = 0xA0E0A0E0;
 381         }
 382
 383         CX18_DEBUG_INFO("Setup VBI h: %d lines %x bpl %d fr %d %x %x\n",
 384                         data[0], data[1], data[2], data[3], data[4], data[5]);
 385
 386         if (s->type == CX18_ENC_STREAM_TYPE_VBI)
 387                 cx18_api(cx, CX18_CPU_SET_RAW_VBI_PARAM, 6, data);
 388 }
 389
 390 int cx18_start_v4l2_encode_stream(struct cx18_stream *s)
 391 {
 392         u32 data[MAX_MB_ARGUMENTS];
 393         struct cx18 *cx = s->cx;
 394         struct list_head *p;
 395         int ts = 0;
 396         int captype = 0;
 397
 398         if (s->v4l2dev == NULL && s->dvb.enabled == 0)
 399                 return -EINVAL;
 400
 401         CX18_DEBUG_INFO("Start encoder stream %s\n", s->name);
 402
 403         switch (s->type) {
 404         case CX18_ENC_STREAM_TYPE_MPG:
 405                 captype = CAPTURE_CHANNEL_TYPE_MPEG;
 406                 cx->mpg_data_received = cx->vbi_data_inserted = 0;
 407                 cx->dualwatch_jiffies = jiffies;
 408                 cx->dualwatch_stereo_mode = cx->params.audio_properties & 0x300;
 409                 cx->search_pack_header = 0;
 410                 break;
 411
 412         case CX18_ENC_STREAM_TYPE_TS:
 413                 captype = CAPTURE_CHANNEL_TYPE_TS;
 414                 ts = 1;
 415                 break;
 416         case CX18_ENC_STREAM_TYPE_YUV:
 417                 captype = CAPTURE_CHANNEL_TYPE_YUV;
 418                 break;
 419         case CX18_ENC_STREAM_TYPE_PCM:
 420                 captype = CAPTURE_CHANNEL_TYPE_PCM;
 421                 break;
 422         case CX18_ENC_STREAM_TYPE_VBI:
 423                 captype = cx->vbi.sliced_in->service_set ?
 424                     CAPTURE_CHANNEL_TYPE_SLICED_VBI : CAPTURE_CHANNEL_TYPE_VBI;
 425                 cx->vbi.frame = 0;
 426                 cx->vbi.inserted_frame = 0;
 427                 memset(cx->vbi.sliced_mpeg_size,
 428                         0, sizeof(cx->vbi.sliced_mpeg_size));
 429                 break;
 430         default:
 431                 return -EINVAL;
 432         }
 433         s->buffers_stolen = 0;
 434
 435         /* mute/unmute video */
 436         cx18_vapi(cx, CX18_CPU_SET_VIDEO_MUTE, 2,
 437                   s->handle, !!test_bit(CX18_F_I_RADIO_USER, &cx->i_flags));
 438
 439         /* Clear Streamoff flags in case left from last capture */
 440         clear_bit(CX18_F_S_STREAMOFF, &s->s_flags);
 441
 442         cx18_vapi_result(cx, data, CX18_CREATE_TASK, 1, CPU_CMD_MASK_CAPTURE);
 443         s->handle = data[0];
 444         cx18_vapi(cx, CX18_CPU_SET_CHANNEL_TYPE, 2, s->handle, captype);
 445
 446         if (atomic_read(&cx->capturing) == 0 && !ts) {
 447                 /* Stuff from Windows, we don't know what it is */
 448                 cx18_vapi(cx, CX18_CPU_SET_VER_CROP_LINE, 2, s->handle, 0);
 449                 cx18_vapi(cx, CX18_CPU_SET_MISC_PARAMETERS, 3, s->handle, 3, 1);
 450                 cx18_vapi(cx, CX18_CPU_SET_MISC_PARAMETERS, 3, s->handle, 8, 0);
 451                 cx18_vapi(cx, CX18_CPU_SET_MISC_PARAMETERS, 3, s->handle, 4, 1);
 452                 cx18_vapi(cx, CX18_CPU_SET_MISC_PARAMETERS, 2, s->handle, 12);
 453
 454                 cx18_vapi(cx, CX18_CPU_SET_CAPTURE_LINE_NO, 3,
 455                                s->handle, cx->digitizer, cx->digitizer);
 456
 457                 /* Setup VBI */
 458                 if (cx->v4l2_cap & V4L2_CAP_VBI_CAPTURE)
 459                         cx18_vbi_setup(s);
 460
 461                 /* assign program index info.
 462                    Mask 7: select I/P/B, Num_req: 400 max */
 463                 cx18_vapi_result(cx, data, CX18_CPU_SET_INDEXTABLE, 1, 0);
 464
 465                 /* Setup API for Stream */
 466                 cx2341x_update(cx, cx18_api_func, NULL, &cx->params);
 467         }
 468
 469         if (atomic_read(&cx->capturing) == 0) {
 470                 clear_bit(CX18_F_I_EOS, &cx->i_flags);
 471                 write_reg(7, CX18_DSP0_INTERRUPT_MASK);
 472         }
 473
 474         cx18_vapi(cx, CX18_CPU_DE_SET_MDL_ACK, 3, s->handle,
 475                 (void *)&cx->scb->cpu_mdl_ack[s->type][0] - cx->enc_mem,
 476                 (void *)&cx->scb->cpu_mdl_ack[s->type][1] - cx->enc_mem);
 477
 478         list_for_each(p, &s->q_free.list) {
 479                 struct cx18_buffer *buf = list_entry(p, struct cx18_buffer, list);
 480
 481                 writel(buf->dma_handle, &cx->scb->cpu_mdl[buf->id].paddr);
 482                 writel(s->buf_size, &cx->scb->cpu_mdl[buf->id].length);
 483                 cx18_vapi(cx, CX18_CPU_DE_SET_MDL, 5, s->handle,
 484                         (void *)&cx->scb->cpu_mdl[buf->id] - cx->enc_mem, 1,
 485                         buf->id, s->buf_size);
 486         }
 487         /* begin_capture */
 488         if (cx18_vapi(cx, CX18_CPU_CAPTURE_START, 1, s->handle)) {
 489                 CX18_DEBUG_WARN("Error starting capture!\n");
 490                 cx18_vapi(cx, CX18_DESTROY_TASK, 1, s->handle);
 491                 return -EINVAL;
 492         }
 493
 494         /* you're live! sit back and await interrupts :) */
 495         atomic_inc(&cx->capturing);
 496         return 0;
 497 }
 498
 499 void cx18_stop_all_captures(struct cx18 *cx)
 500 {
 501         int i;
 502
 503         for (i = CX18_MAX_STREAMS - 1; i >= 0; i--) {
 504                 struct cx18_stream *s = &cx->streams[i];
 505
 506                 if (s->v4l2dev == NULL && s->dvb.enabled == 0)
 507                         continue;
 508                 if (test_bit(CX18_F_S_STREAMING, &s->s_flags))
 509                         cx18_stop_v4l2_encode_stream(s, 0);
 510         }
 511 }
 512
 513 int cx18_stop_v4l2_encode_stream(struct cx18_stream *s, int gop_end)
 514 {
 515         struct cx18 *cx = s->cx;
 516         unsigned long then;
 517
 518         if (s->v4l2dev == NULL && s->dvb.enabled == 0)
 519                 return -EINVAL;
 520
 521         /* This function assumes that you are allowed to stop the capture
 522            and that we are actually capturing */
 523
 524         CX18_DEBUG_INFO("Stop Capture\n");
 525
 526         if (atomic_read(&cx->capturing) == 0)
 527                 return 0;
 528
 529         if (s->type == CX18_ENC_STREAM_TYPE_MPG)
 530                 cx18_vapi(cx, CX18_CPU_CAPTURE_STOP, 2, s->handle, !gop_end);
 531         else
 532                 cx18_vapi(cx, CX18_CPU_CAPTURE_STOP, 1, s->handle);
 533
 534         then = jiffies;
 535
 536         if (s->type == CX18_ENC_STREAM_TYPE_MPG && gop_end) {
 537                 CX18_INFO("ignoring gop_end: not (yet?) supported by the firmware\n");
 538         }
 539
 540         atomic_dec(&cx->capturing);
 541
 542         /* Clear capture and no-read bits */
 543         clear_bit(CX18_F_S_STREAMING, &s->s_flags);
 544
 545         cx18_vapi(cx, CX18_DESTROY_TASK, 1, s->handle);
 546         s->handle = 0xffffffff;
 547
 548         if (atomic_read(&cx->capturing) > 0)
 549                 return 0;
 550
 551         write_reg(5, CX18_DSP0_INTERRUPT_MASK);
 552         wake_up(&s->waitq);
 553
 554         return 0;
 555 }
 556
 557 u32 cx18_find_handle(struct cx18 *cx)
 558 {
 559         int i;
 560
 561         /* find first available handle to be used for global settings */
 562         for (i = 0; i < CX18_MAX_STREAMS; i++) {
 563                 struct cx18_stream *s = &cx->streams[i];
 564
 565                 if (s->v4l2dev && s->handle)
 566                         return s->handle;
 567         }
 568         return 0;
 569 }