Re: [alsa-devel] [PATCH] ASoC: tda998x: add a codec to the HDMI transmitter

On Wed, 2 Jul 2014 20:42:52 +0100 Mark Brown broonie@kernel.org wrote:

...

I tested this CODEC with both DAPM and DPCM. If the audio subsystem asks for streaming on both I2S and S/PDIF, only the last call is served (this depends on the order of the DAI links in the audio card creation table).

I'd expect this to return an error for the busy DAI rather than just silently ignore it failing to start or (better) implement some control to let the user select which of the DAIs is active.

Mark,

This is not an error. If the audio subsystem (DPCM, not the user) chooses to activate both I2S and S/PDIF, this means the HDMI audio may be taken either from I2S or from S/PDIF: both inputs have the right format and rate.