[PATCH] ASoC: tda998x: add a codec to the HDMI transmitter

Jean-Francois Moine moinejf at free.fr
Wed Jul 2 10:51:54 PDT 2014


On Wed, 2 Jul 2014 18:56:28 +0200
Andrew Lunn <andrew at lunn.ch> wrote:

> How well will this work with Russell concept of a front end and two
> backends? Can you uses your CODEC twice, once with the I2S backend and
> a second time with the S/PDIF backend?

Hi Andrew,

The TDA998x CODEC has two functions:
- it sets the possible formats and rates when the screen connects and
- it sets the audio input port when audio streaming starts.

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).

As I told to Russell, DPCM just asks for a 'system' DAI (front-end),
but it also asks for some additional code in the kirkwood DMA driver
because all PCMs are activated on streaming start.

-- 
Ken ar c'hentañ	|	      ** Breizh ha Linux atav! **
Jef		|		http://moinejf.free.fr/



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