diff options
| author | Takashi Sakamoto <o-takashi@sakamocchi.jp> | 2015-09-19 11:21:57 +0900 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2015-09-29 12:48:19 +0200 |
| commit | bc8500da3e62cd6a896407a1b330a2eb21817c22 (patch) | |
| tree | 74259f781b6999135349f5670c0bbd907f28936f /sound/firewire/amdtp-am824.c | |
| parent | 51c29fd21389d9995a8a18a91eeb8dd1220a2119 (diff) | |
ALSA: firewire-lib: move PCM substream constraint to AM824 layer
In IEC 61883-6, PCM frames are transferred in Multi Bit Linear Audio data
channel. The data channel transfers 16/20/24 bit PCM samples. Thus, PCM
substream has a constrain about it.
This commit moves codes related to the constraint from packet streaming
layer to AM824 data block processing layer.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/firewire/amdtp-am824.c')
| -rw-r--r-- | sound/firewire/amdtp-am824.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/sound/firewire/amdtp-am824.c b/sound/firewire/amdtp-am824.c index f5edcbfa3157..7adaba356579 100644 --- a/sound/firewire/amdtp-am824.c +++ b/sound/firewire/amdtp-am824.c @@ -53,6 +53,26 @@ int amdtp_am824_set_parameters(struct amdtp_stream *s, unsigned int rate, EXPORT_SYMBOL_GPL(amdtp_am824_set_parameters); /** + * amdtp_am824_add_pcm_hw_constraints - add hw constraints for PCM substream + * @s: the AMDTP stream for AM824 data block, must be initialized. + * @runtime: the PCM substream runtime + * + */ +int amdtp_am824_add_pcm_hw_constraints(struct amdtp_stream *s, + struct snd_pcm_runtime *runtime) +{ + int err; + + err = amdtp_stream_add_pcm_hw_constraints(s, runtime); + if (err < 0) + return err; + + /* AM824 in IEC 61883-6 can deliver 24bit data. */ + return snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24); +} +EXPORT_SYMBOL_GPL(amdtp_am824_add_pcm_hw_constraints); + +/** * amdtp_am824_init - initialize an AMDTP stream structure to handle AM824 * data block * @s: the AMDTP stream to initialize |