modules/access/dv.c

   1 /*****************************************************************************
   2  * dv.c: Digital video/Firewire input (file: access plug-in)
   3  *****************************************************************************
   4  * Copyright (C) 2005 M2X
   5  * $Id$
   6  *
   7  * Authors: Jean-Paul Saman <jpsaman at m2x dot nl>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, write to the Free Software Foundation, Inc.,
  21  * 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27 #ifdef HAVE_CONFIG_H
  28 # include "config.h"
  29 #endif
  30
  31 #include <vlc_common.h>
  32 #include <vlc_plugin.h>
  33 #include <vlc_access.h>
  34
  35 #include <errno.h>
  36 #include <sys/types.h>
  37 #ifdef HAVE_UNISTD_H
  38 #   include <unistd.h>
  39 #elif defined( WIN32 ) && !defined( UNDER_CE )
  40 #   include <io.h>
  41 #endif
  42
  43 #include <sys/poll.h>
  44
  45 #include <libraw1394/raw1394.h>
  46 #include <libraw1394/csr.h>
  47 #include <libavc1394/avc1394.h>
  48 #include <libavc1394/avc1394_vcr.h>
  49 #include <libavc1394/rom1394.h>
  50
  51 /*****************************************************************************
  52  * Module descriptor
  53  *****************************************************************************/
  54 static int  Open ( vlc_object_t * );
  55 static void Close( vlc_object_t * );
  56 static block_t *Block( access_t * );
  57 static int Control( access_t *, int, va_list );
  58
  59 #define CACHING_TEXT N_("Caching value in ms")
  60 #define CACHING_LONGTEXT N_( \
  61     "Caching value for DV streams. This " \
  62     "value should be set in milliseconds." )
  63
  64 vlc_module_begin ()
  65     set_description( N_("Digital Video (Firewire/ieee1394)  input") )
  66     set_shortname( N_("DV") )
  67     set_category( CAT_INPUT )
  68     set_subcategory( SUBCAT_INPUT_ACCESS )
  69     add_integer( "dv-caching", 60000 / 1000, NULL, CACHING_TEXT, CACHING_LONGTEXT, true )
  70         change_safe()
  71     set_capability( "access", 0 )
  72     add_shortcut( "dv" )
  73     add_shortcut( "dv1394" )
  74     add_shortcut( "raw1394" )
  75     set_callbacks( Open, Close )
  76 vlc_module_end ()
  77
  78 typedef struct
  79 {
  80     VLC_COMMON_MEMBERS
  81
  82     access_t        *p_access;
  83     vlc_mutex_t     lock;
  84     block_t         *p_frame;
  85     block_t         **pp_last;
  86
  87 } event_thread_t;
  88
  89 static void* Raw1394EventThread( vlc_object_t * );
  90 static enum raw1394_iso_disposition
  91 Raw1394Handler(raw1394handle_t, unsigned char *,
  92         unsigned int, unsigned char,
  93         unsigned char, unsigned char, unsigned int,
  94         unsigned int);
  95
  96 static int Raw1394GetNumPorts( access_t *p_access );
  97 static raw1394handle_t Raw1394Open( access_t *, int );
  98 static void Raw1394Close( raw1394handle_t );
  99
 100 static int DiscoverAVC( access_t *, int *, uint64_t );
 101 static raw1394handle_t AVCOpen( access_t *, int );
 102 static void AVCClose( access_t * );
 103 static int AVCResetHandler( raw1394handle_t, unsigned int );
 104 static int AVCPlay( access_t *, int );
 105 static int AVCPause( access_t *, int );
 106 static int AVCStop( access_t *, int );
 107
 108 struct access_sys_t
 109 {
 110     raw1394handle_t p_avc1394;
 111     raw1394handle_t p_raw1394;
 112     struct pollfd   raw1394_poll;
 113
 114     int i_cards;
 115     int i_node;
 116     int i_port;
 117     int i_channel;
 118     uint64_t i_guid;
 119
 120     /* event */
 121     event_thread_t *p_ev;
 122     vlc_mutex_t lock;
 123     block_t *p_frame;
 124 };
 125
 126 #define ISOCHRONOUS_QUEUE_LENGTH 1000
 127 #define ISOCHRONOUS_MAX_PACKET_SIZE 4096
 128
 129 /*****************************************************************************
 130  * Open: open the file
 131  *****************************************************************************/
 132 static int Open( vlc_object_t *p_this )
 133 {
 134     access_t     *p_access = (access_t*)p_this;
 135     access_sys_t *p_sys;
 136     char *psz_name = strdup( p_access->psz_path );
 137
 138     struct raw1394_portinfo port_inf[ 16 ];
 139
 140     msg_Dbg( p_access, "opening device %s", psz_name );
 141
 142     /* Set up p_access */
 143     access_InitFields( p_access );
 144     ACCESS_SET_CALLBACKS( NULL, Block, Control, NULL );
 145
 146     p_access->p_sys = p_sys = malloc( sizeof( access_sys_t ) );
 147     if( !p_sys )
 148     {
 149         free( psz_name );
 150         return VLC_EGENERIC;
 151     }
 152
 153     p_sys->i_cards = 0;
 154     p_sys->i_node = 0;
 155     p_sys->i_port = 0;
 156     p_sys->i_guid = 0;
 157     p_sys->i_channel = 63;
 158     p_sys->p_raw1394 = NULL;
 159     p_sys->p_avc1394 = NULL;
 160     p_sys->p_frame = NULL;
 161     p_sys->p_ev = NULL;
 162
 163     vlc_mutex_init( &p_sys->lock );
 164
 165     p_sys->i_node = DiscoverAVC( p_access, &p_sys->i_port, p_sys->i_guid );
 166     if( p_sys->i_node < 0 )
 167     {
 168         msg_Err( p_access, "failed to open a Firewire (IEEE1394) connection" );
 169         Close( p_this );
 170         free( psz_name );
 171         return VLC_EGENERIC;
 172     }
 173
 174     p_sys->p_avc1394 = AVCOpen( p_access, p_sys->i_port );
 175     if( !p_sys->p_avc1394 )
 176     {
 177         msg_Err( p_access, "no Digital Video Control device found on %s", psz_name );
 178         Close( p_this );
 179         free( psz_name );
 180         return VLC_EGENERIC;
 181     }
 182
 183     p_sys->p_raw1394 = raw1394_new_handle();
 184     if( !p_sys->p_raw1394 )
 185     {
 186         msg_Err( p_access, "no Digital Video device found on %s", psz_name );
 187         Close( p_this );
 188         free( psz_name );
 189         return VLC_EGENERIC;
 190     }
 191
 192     p_sys->i_cards = raw1394_get_port_info( p_sys->p_raw1394, port_inf, 16 );
 193     if( p_sys->i_cards < 0 )
 194     {
 195         msg_Err( p_access, "failed to get port info for %s", psz_name );
 196         Close( p_this );
 197         free( psz_name );
 198         return VLC_EGENERIC;
 199     }
 200
 201     if( raw1394_set_port( p_sys->p_raw1394, p_sys->i_port ) < 0 )
 202     {
 203         msg_Err( p_access, "failed to set port info for %s", psz_name );
 204         Close( p_this );
 205         free( psz_name );
 206         return VLC_EGENERIC;
 207     }
 208
 209     if ( raw1394_iso_recv_init( p_sys->p_raw1394, Raw1394Handler,
 210                 ISOCHRONOUS_QUEUE_LENGTH, ISOCHRONOUS_MAX_PACKET_SIZE,
 211                 p_sys->i_channel, RAW1394_DMA_PACKET_PER_BUFFER, -1 ) < 0 )
 212     {
 213         msg_Err( p_access, "failed to init isochronous recv for %s", psz_name );
 214         Close( p_this );
 215         free( psz_name );
 216         return VLC_EGENERIC;
 217     }
 218
 219     raw1394_set_userdata( p_sys->p_raw1394, p_access );
 220     raw1394_iso_recv_start( p_sys->p_raw1394, -1, -1, 0 );
 221
 222     p_sys->raw1394_poll.fd = raw1394_get_fd( p_sys->p_raw1394 );
 223     p_sys->raw1394_poll.events = POLLIN | POLLPRI;
 224
 225     /* Update default_pts to a suitable value for udp access */
 226     var_Create( p_access, "dv-caching", VLC_VAR_INTEGER | VLC_VAR_DOINHERIT );
 227
 228     /* Now create our event thread catcher */
 229     p_sys->p_ev = vlc_object_create( p_access, sizeof( event_thread_t ) );
 230     if( !p_sys->p_ev )
 231     {
 232         msg_Err( p_access, "failed to create event thread for %s", psz_name );
 233         Close( p_this );
 234         free( psz_name );
 235         return VLC_EGENERIC;
 236     }
 237
 238     p_sys->p_ev->p_frame = NULL;
 239     p_sys->p_ev->pp_last = &p_sys->p_ev->p_frame;
 240     p_sys->p_ev->p_access = p_access;
 241     vlc_mutex_init( &p_sys->p_ev->lock );
 242     vlc_thread_create( p_sys->p_ev, "dv event thread handler",
 243                        Raw1394EventThread, VLC_THREAD_PRIORITY_OUTPUT );
 244
 245     free( psz_name );
 246     return VLC_SUCCESS;
 247 }
 248
 249 /*****************************************************************************
 250  * Close: free unused data structures
 251  *****************************************************************************/
 252 static void Close( vlc_object_t *p_this )
 253 {
 254     access_t     *p_access = (access_t*)p_this;
 255     access_sys_t *p_sys = p_access->p_sys;
 256
 257     if( p_sys->p_ev )
 258     {
 259         /* stop the event handler */
 260         vlc_object_kill( p_sys->p_ev );
 261
 262         if( p_sys->p_raw1394 )
 263             raw1394_iso_shutdown( p_sys->p_raw1394 );
 264
 265         vlc_thread_join( p_sys->p_ev );
 266         vlc_mutex_destroy( &p_sys->p_ev->lock );
 267
 268         /* Cleanup frame data */
 269         if( p_sys->p_ev->p_frame )
 270         {
 271             block_ChainRelease( p_sys->p_ev->p_frame );
 272             p_sys->p_ev->p_frame = NULL;
 273             p_sys->p_ev->pp_last = &p_sys->p_frame;
 274         }
 275         vlc_object_release( p_sys->p_ev );
 276     }
 277
 278     if( p_sys->p_frame )
 279         block_ChainRelease( p_sys->p_frame );
 280     if( p_sys->p_raw1394 )
 281         raw1394_destroy_handle( p_sys->p_raw1394 );
 282
 283     AVCClose( p_access );
 284
 285     vlc_mutex_destroy( &p_sys->lock );
 286     free( p_sys );
 287 }
 288
 289 /*****************************************************************************
 290  * Control:
 291  *****************************************************************************/
 292 static int Control( access_t *p_access, int i_query, va_list args )
 293 {
 294     switch( i_query )
 295     {
 296         /* */
 297         case ACCESS_CAN_PAUSE:
 298             *va_arg( args, bool* ) = true;
 299             break;
 300
 301        case ACCESS_CAN_SEEK:
 302        case ACCESS_CAN_FASTSEEK:
 303        case ACCESS_CAN_CONTROL_PACE:
 304             *va_arg( args, bool* ) = false;
 305             break;
 306
 307         case ACCESS_GET_PTS_DELAY:
 308             *va_arg( args, int64_t * )
 309                    = (int64_t)var_GetInteger( p_access, "dv-caching" ) * 1000;
 310             break;
 311
 312         /* */
 313         case ACCESS_SET_PAUSE_STATE:
 314             AVCPause( p_access, p_access->p_sys->i_node );
 315             break;
 316
 317         case ACCESS_GET_TITLE_INFO:
 318         case ACCESS_SET_TITLE:
 319         case ACCESS_SET_SEEKPOINT:
 320         case ACCESS_SET_PRIVATE_ID_STATE:
 321         case ACCESS_GET_CONTENT_TYPE:
 322             return VLC_EGENERIC;
 323
 324         default:
 325             msg_Warn( p_access, "unimplemented query in control" );
 326             return VLC_EGENERIC;
 327
 328     }
 329     return VLC_SUCCESS;
 330 }
 331
 332 static block_t *Block( access_t *p_access )
 333 {
 334     access_sys_t *p_sys = p_access->p_sys;
 335     block_t *p_block = NULL;
 336
 337     vlc_mutex_lock( &p_sys->lock );
 338     p_block = p_sys->p_frame;
 339     //msg_Dbg( p_access, "sending frame %p",p_block );
 340     p_sys->p_frame = NULL;
 341     vlc_mutex_unlock( &p_sys->lock );
 342
 343     return p_block;
 344 }
 345
 346 static void* Raw1394EventThread( vlc_object_t *p_this )
 347 {
 348     event_thread_t *p_ev = (event_thread_t *) p_this;
 349     access_t *p_access = (access_t *) p_ev->p_access;
 350     access_sys_t *p_sys = (access_sys_t *) p_access->p_sys;
 351     int result = 0;
 352     int canc = vlc_savecancel ();
 353
 354     AVCPlay( p_access, p_sys->i_node );
 355
 356     while( vlc_object_alive (p_sys->p_ev) )
 357     {
 358         while( ( result = poll( &(p_sys->raw1394_poll), 1, 200 ) ) < 0 )
 359         {
 360             if( !( errno == EAGAIN || errno == EINTR ) )
 361             {
 362                 perror( "error: raw1394 poll" );
 363                 msg_Err( p_access, "retrying device raw1394" );
 364             }
 365         }
 366         if( !vlc_object_alive (p_sys->p_ev) )
 367                 break;
 368         if( result > 0 && ( ( p_sys->raw1394_poll.revents & POLLIN )
 369                 || ( p_sys->raw1394_poll.revents & POLLPRI ) ) )
 370             result = raw1394_loop_iterate( p_sys->p_raw1394 );
 371     }
 372
 373     AVCStop( p_access, p_sys->i_node );
 374     vlc_restorecancel (canc);
 375     return NULL;
 376 }
 377
 378 static enum raw1394_iso_disposition
 379 Raw1394Handler(raw1394handle_t handle, unsigned char *data,
 380         unsigned int length, unsigned char channel,
 381         unsigned char tag, unsigned char sy, unsigned int cycle,
 382         unsigned int dropped)
 383 {
 384     access_t *p_access = NULL;
 385     access_sys_t *p_sys = NULL;
 386     block_t *p_block = NULL;
 387     VLC_UNUSED(channel); VLC_UNUSED(tag);
 388     VLC_UNUSED(sy); VLC_UNUSED(cycle); VLC_UNUSED(dropped);
 389
 390     p_access = (access_t *) raw1394_get_userdata( handle );
 391     if( !p_access ) return 0;
 392
 393     p_sys = p_access->p_sys;
 394
 395     /* skip empty packets */
 396     if( length > 16 )
 397     {
 398         unsigned char * p = data + 8;
 399         int section_type = p[ 0 ] >> 5;           /* section type is in bits 5 - 7 */
 400         int dif_sequence = p[ 1 ] >> 4;           /* dif sequence number is in bits 4 - 7 */
 401         int dif_block = p[ 2 ];
 402
 403         vlc_mutex_lock( &p_sys->p_ev->lock );
 404
 405         /* if we are at the beginning of a frame, we put the previous
 406            frame in our output_queue. */
 407         if( (section_type == 0) && (dif_sequence == 0) )
 408         {
 409             vlc_mutex_lock( &p_sys->lock );
 410             if( p_sys->p_ev->p_frame )
 411             {
 412                 /* Push current frame to p_access thread. */
 413                 //p_sys->p_ev->p_frame->i_pts = mdate();
 414                 block_ChainAppend( &p_sys->p_frame, p_sys->p_ev->p_frame );
 415             }
 416             /* reset list */
 417             p_sys->p_ev->p_frame = block_New( p_access, 144000 );
 418             p_sys->p_ev->pp_last = &p_sys->p_frame;
 419             vlc_mutex_unlock( &p_sys->lock );
 420         }
 421
 422         p_block = p_sys->p_ev->p_frame;
 423         if( p_block )
 424         {
 425             switch ( section_type )
 426             {
 427             case 0:    /* 1 Header block */
 428                 /* p[3] |= 0x80; // hack to force PAL data */
 429                 memcpy( p_block->p_buffer + dif_sequence * 150 * 80, p, 480 );
 430                 break;
 431
 432             case 1:    /* 2 Subcode blocks */
 433                 memcpy( p_block->p_buffer + dif_sequence * 150 * 80 + ( 1 + dif_block ) * 80, p, 480 );
 434                 break;
 435
 436             case 2:    /* 3 VAUX blocks */
 437                 memcpy( p_block->p_buffer + dif_sequence * 150 * 80 + ( 3 + dif_block ) * 80, p, 480 );
 438                 break;
 439
 440             case 3:    /* 9 Audio blocks interleaved with video */
 441                 memcpy( p_block->p_buffer + dif_sequence * 150 * 80 + ( 6 + dif_block * 16 ) * 80, p, 480 );
 442                 break;
 443
 444             case 4:    /* 135 Video blocks interleaved with audio */
 445                 memcpy( p_block->p_buffer + dif_sequence * 150 * 80 + ( 7 + ( dif_block / 15 ) + dif_block ) * 80, p, 480 );
 446                 break;
 447
 448             default:    /* we can´t handle any other data */
 449                 block_Release( p_block );
 450                 p_block = NULL;
 451                 break;
 452             }
 453         }
 454
 455         vlc_mutex_unlock( &p_sys->p_ev->lock );
 456     }
 457     return 0;
 458 }
 459
 460 /*
 461  * Routing borrowed from dvgrab-1.8
 462  * Copyright by Arne Schirmacher <dvgrab@schirmacher.de>
 463  * Dan Dennedy <dan@dennedy.org> and others
 464  */
 465 static int Raw1394GetNumPorts( access_t *p_access )
 466 {
 467     int n_ports;
 468     struct raw1394_portinfo pinf[ 16 ];
 469     raw1394handle_t handle;
 470
 471     /* get a raw1394 handle */
 472     if( !( handle = raw1394_new_handle() ) )
 473     {
 474         msg_Err( p_access, "raw1394 - failed to get handle: %m." );
 475         return VLC_EGENERIC;
 476     }
 477
 478     if( ( n_ports = raw1394_get_port_info( handle, pinf, 16 ) ) < 0 )
 479     {
 480         msg_Err( p_access, "raw1394 - failed to get port info: %m." );
 481         raw1394_destroy_handle( handle );
 482         return VLC_EGENERIC;
 483     }
 484     raw1394_destroy_handle( handle );
 485
 486     return n_ports;
 487 }
 488
 489 static raw1394handle_t Raw1394Open( access_t *p_access, int port )
 490 {
 491     int n_ports;
 492     struct raw1394_portinfo pinf[ 16 ];
 493     raw1394handle_t handle;
 494
 495     /* get a raw1394 handle */
 496     handle = raw1394_new_handle();
 497     if( !handle )
 498     {
 499         msg_Err( p_access, "raw1394 - failed to get handle: %m." );
 500         return NULL;
 501     }
 502
 503     if( ( n_ports = raw1394_get_port_info( handle, pinf, 16 ) ) < 0 )
 504     {
 505         msg_Err( p_access, "raw1394 - failed to get port info: %m." );
 506         raw1394_destroy_handle( handle );
 507         return NULL;
 508     }
 509
 510     /* tell raw1394 which host adapter to use */
 511     if( raw1394_set_port( handle, port ) < 0 )
 512     {
 513         msg_Err( p_access, "raw1394 - failed to set set port: %m." );
 514         return NULL;
 515     }
 516
 517     return handle;
 518 }
 519
 520 static void Raw1394Close( raw1394handle_t handle )
 521 {
 522     raw1394_destroy_handle( handle );
 523 }
 524
 525 static int DiscoverAVC( access_t *p_access, int* port, uint64_t guid )
 526 {
 527     rom1394_directory rom_dir;
 528     raw1394handle_t handle = NULL;
 529     int device = -1;
 530     int i, j = 0;
 531     int m = Raw1394GetNumPorts( p_access );
 532
 533     if( *port >= 0 )
 534     {
 535         /* search on explicit port */
 536         j = *port;
 537         m = *port + 1;
 538     }
 539
 540     for( ; j < m && device == -1; j++ )
 541     {
 542         handle = Raw1394Open( p_access, j );
 543         if( !handle )
 544             return -1;
 545
 546         for( i = 0; i < raw1394_get_nodecount( handle ); ++i )
 547         {
 548             if( guid != 0 )
 549             {
 550                 /* select explicitly by GUID */
 551                 if( guid == rom1394_get_guid( handle, i ) )
 552                 {
 553                     device = i;
 554                     *port = j;
 555                     break;
 556                 }
 557             }
 558             else
 559             {
 560                 /* select first AV/C Tape Reccorder Player node */
 561                 if( rom1394_get_directory( handle, i, &rom_dir ) < 0 )
 562                 {
 563                     msg_Err( p_access, "error reading config rom directory for node %d", i );
 564                     continue;
 565                 }
 566                 if( ( rom1394_get_node_type( &rom_dir ) == ROM1394_NODE_TYPE_AVC ) &&
 567                         avc1394_check_subunit_type( handle, i, AVC1394_SUBUNIT_TYPE_VCR ) )
 568                 {
 569                     device = i;
 570                     *port = j;
 571                     break;
 572                 }
 573             }
 574         }
 575         Raw1394Close( handle );
 576     }
 577
 578     return device;
 579 }
 580
 581 /*
 582  * Handle AVC commands
 583  */
 584 static raw1394handle_t AVCOpen( access_t *p_access, int port )
 585 {
 586     access_sys_t *p_sys = p_access->p_sys;
 587     struct raw1394_portinfo pinf[ 16 ];
 588     int numcards;
 589
 590     p_sys->p_avc1394 = raw1394_new_handle();
 591     if( !p_sys->p_avc1394 )
 592         return NULL;
 593
 594     numcards = raw1394_get_port_info( p_sys->p_avc1394, pinf, 16 );
 595     if( numcards < -1 )
 596         return NULL;
 597     if( raw1394_set_port( p_sys->p_avc1394, port ) < 0 )
 598         return NULL;
 599
 600     raw1394_set_bus_reset_handler( p_sys->p_avc1394, AVCResetHandler );
 601
 602     return  p_sys->p_avc1394;
 603 }
 604
 605 static void AVCClose( access_t *p_access )
 606 {
 607     access_sys_t *p_sys = p_access->p_sys;
 608
 609     if( p_sys->p_avc1394 )
 610     {
 611         raw1394_destroy_handle( p_sys->p_avc1394 );
 612         p_sys->p_avc1394 = NULL;
 613     }
 614 }
 615
 616 static int AVCResetHandler( raw1394handle_t handle, unsigned int generation )
 617 {
 618     raw1394_update_generation( handle, generation );
 619     return 0;
 620 }
 621
 622 static int AVCPlay( access_t *p_access, int phyID )
 623 {
 624     access_sys_t *p_sys = p_access->p_sys;
 625
 626     msg_Dbg( p_access, "send play command over Digital Video control channel" );
 627
 628     if( p_sys->p_avc1394 && phyID >= 0 )
 629     {
 630         if( !avc1394_vcr_is_recording( p_sys->p_avc1394, phyID ) &&
 631             avc1394_vcr_is_playing( p_sys->p_avc1394, phyID ) != AVC1394_VCR_OPERAND_PLAY_FORWARD )
 632                 avc1394_vcr_play( p_sys->p_avc1394, phyID );
 633     }
 634     return 0;
 635 }
 636
 637 static int AVCPause( access_t *p_access, int phyID )
 638 {
 639     access_sys_t *p_sys = p_access->p_sys;
 640
 641     if( p_sys->p_avc1394 && phyID >= 0 )
 642     {
 643         if( !avc1394_vcr_is_recording( p_sys->p_avc1394, phyID ) &&
 644             ( avc1394_vcr_is_playing( p_sys->p_avc1394, phyID ) != AVC1394_VCR_OPERAND_PLAY_FORWARD_PAUSE ) )
 645                 avc1394_vcr_pause( p_sys->p_avc1394, phyID );
 646     }
 647     return 0;
 648 }
 649
 650
 651 static int AVCStop( access_t *p_access, int phyID )
 652 {
 653     access_sys_t *p_sys = p_access->p_sys;
 654
 655     msg_Dbg( p_access, "closing Digital Video control channel" );
 656
 657     if ( p_sys->p_avc1394 && phyID >= 0 )
 658         avc1394_vcr_stop( p_sys->p_avc1394, phyID );
 659
 660     return 0;
 661 }