• Takashi Sakamoto's avatar
    ALSA: oxfw: Add support AMDTP in-stream · b0ac0009
    Takashi Sakamoto authored
    Previous commit adds support for some devices which can capture PCM samples.
    These devices transmit AMDTP stream in non-blocking mode. This commit adds
    functionality to handle AMDTP incoming stream.
    
    OXFW seems to have two quirks:
     - Transmits packets with non-zero dbc in its beginning
     - Transmits packets with wrong values in syt field
    
    For the first quirk, this commit adds CIP_SKIP_INIT_DBC_CHECK flag for
    incoming stream to skip first check of dbc.
    
    For the second quirk, this commit doesn't add duplex stream which
    Fireworks/BeBoB drivers use. So OXFW driver generates syt value for outgoing
    stream.
    
    Here are examples of a sequence of packets transmitted by Behringer F-Control
    Audio 202. There are differences between sequences of syt value when OXFW
    driver transfers outgoing stream or not.
    
    When driver gives no outgoing stream:
    Index   Payload CIP_Header_0    CIP_Header_1
    38      14      00020092        900103D1
    39      12      00020098        900102FF
    40      12      0002009D        9001027F
    41      14      000200A2        90010396
    42      14      000200A8        900102E8
    43      12      000200AE        90010219
    44      14      000200B3        90010331
    45      12      000200B9        9001025F
    46      14      000200BE        90010376
    47      12      000200C4        900102A1
    00      12      000200C9        9001023E
    01      14      000200CE        90010358
    02      12      000200D4        90010289
    03      16      000200D9        900103A3
    04      12      000200E0        900102DD
    05      14      000200E5        900103F1
    06      12      000200EB        90010335
    07      12      000200F0        90010263
    08      14      000200F5        9001037C
    09      12      000200FB        900102AE
    
    When driver gives outgoing stream:
    Index   Payload CIP_Header_0    CIP_Header_1
    38      12      000200BD        900104A8
    39      14      000200C2        900104A8
    40      12      000200C8        900104AC
    41      14      000200CD        900104A9
    42      12      000200D3        900104B1
    43      14      000200D8        900104A8
    44      12      000200DE        900104AA
    45      14      000200E3        900104A9
    46      14      000200E9        900104AE
    47      12      000200EF        900104A8
    00      14      000200F4        900104AD
    01      12      000200FA        900104A7
    02      14      000200FF        900104A9
    03      12      00020005        900104A9
    04      14      0002000A        900104B1
    05      12      00020010        900104AA
    06      14      00020015        900104AD
    07      12      0002001B        900104A7
    08      14      00020020        900104AC
    09      12      00020026        900104A7
    Signed-off-by: default avatarTakashi Sakamoto <o-takashi@sakamocchi.jp>
    Acked-by: default avatarClemens Ladisch <clemens@ladisch.de>
    Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
    b0ac0009
oxfw-pcm.c 6.3 KB