In IEC 61883-6, AM824 is described as format of data block. In this
format, one data block consists of several data channels, which is aligned
to 32 bit. One data channel has 8 bit label field and 24 bit data field.
PCM frames are transferred in Multi Bit Linear Audio (MBLA) data channel.
This channel can include 16/20/24 bit PCM sample.
As long as I know, models which support IEC 61883-1/6 doesn't allow to
switch bit length of PCM sample in MBLA data channel. They always
transmit/receive PCM frames of 24 bit length. This can be seen for the
other models which support protocols similar to IEC 61883-1/6.
On the other hand, current drivers for these protocols supports 16 bit
length PCM sample in playback substream. In this case, PCM sample is put
into the MBLA data channel with 8 bit padding in LSB side. Although 16
bit PCM sample is major because it's in CD format, this doesn't represent
device capability as is.
This commit removes support for 16 bit PCM samples in playback substream.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Acked-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
TASCAM FireWire series uses non-blocking transmission for AMDTP packet
streaming, while the format of data blocks is unique.
The CIP headers includes specific value in FMT field and no SYT
information.
In transmitted packets, the first data channel represents event counter,
and the last data channel has status and control information. The rest
has 24bit PCM samples with right padding.
In received packets, all of data channels include 16, 24, 32bit PCM
samples. There's no other kind of information.
This commit adds support for this protocol. For convenience, the size of
PCM samples in outgoing packet is limited by 16 and 24bit. The status and
control information will be supported in future commits.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
