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authorTakashi Sakamoto <o-takashi@sakamocchi.jp>2017-05-22 15:22:21 +0200
committerTakashi Iwai <tiwai@suse.de>2017-05-22 16:24:08 +0200
commita02cb8f8def634159b60c3a4d6ba16e471b46e0c (patch)
treed7d6cc26b7747ce434433d9723d1afcc9b7cfc2b /sound/firewire/fireworks
parentALSA: mixart: constify snd_kcontrol_new structures (diff)
downloadlinux-a02cb8f8def634159b60c3a4d6ba16e471b46e0c.tar.xz
linux-a02cb8f8def634159b60c3a4d6ba16e471b46e0c.zip
ALSA: firewire: remove support for 16 bit PCM samples in playback substream
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>
Diffstat (limited to 'sound/firewire/fireworks')
-rw-r--r--sound/firewire/fireworks/fireworks_pcm.c4
1 files changed, 0 insertions, 4 deletions
diff --git a/sound/firewire/fireworks/fireworks_pcm.c b/sound/firewire/fireworks/fireworks_pcm.c
index 9171702f7d0b..f10aec117998 100644
--- a/sound/firewire/fireworks/fireworks_pcm.c
+++ b/sound/firewire/fireworks/fireworks_pcm.c
@@ -257,8 +257,6 @@ static int pcm_capture_hw_params(struct snd_pcm_substream *substream,
mutex_unlock(&efw->mutex);
}
- amdtp_am824_set_pcm_format(&efw->tx_stream, params_format(hw_params));
-
return 0;
}
static int pcm_playback_hw_params(struct snd_pcm_substream *substream,
@@ -278,8 +276,6 @@ static int pcm_playback_hw_params(struct snd_pcm_substream *substream,
mutex_unlock(&efw->mutex);
}
- amdtp_am824_set_pcm_format(&efw->rx_stream, params_format(hw_params));
-
return 0;
}