ASoC: How to connect a single CPU DAI to two codecs?

ASoC: How to connect a single CPU DAI to two codecs?

[Sergej Sawazki]

Hello,

I'm writing an ALSA SoC machine driver for a board that has two mono 
codecs (left and right audio channel). Each codec is controlled over I2C 
and has itsown address.Both codecs are connected to the same I2S CPU DAI 
(as shown below).

     +--------- (adr: 0x1a) -----+
     |                           |
     |             +--------> codec_1 ----> (left channel audio)
     |             |
    I2C    I2S ----+
     |             |
     |             +--------> codec_2 ----> (right channel audio)
     |                           |
     +--------- (adr: 0x1b) -----+

Can someone give me some advice on how to setup the 'snd_soc_card' and 'snd_soc_dai_link' in this case? Do I need two dai_links with the same 'cpu_dai_name' and 'platform_name'?

Are there examples for such a configuration? I didn't had much luck in finding one in the mainline?

Any help would be highly appreciated.  Thanks!

Sergej

Re: ASoC: How to connect a single CPU DAI to two codecs?

[Lars-Peter Clausen]

On 09/27/2014 03:33 PM, Sergej Sawazki wrote:
> Hello,
>
> I'm writing an ALSA SoC machine driver for a board that has two mono codecs
> (left and right audio channel). Each codec is controlled over I2C and has
> itsown address.Both codecs are connected to the same I2S CPU DAI (as shown
> below).
>
>      +--------- (adr: 0x1a) -----+
>      |                           |
>      |             +--------> codec_1 ----> (left channel audio)
>      |             |
>     I2C    I2S ----+
>      |             |
>      |             +--------> codec_2 ----> (right channel audio)
>      |                           |
>      +--------- (adr: 0x1b) -----+
>
> Can someone give me some advice on how to setup the 'snd_soc_card' and
> 'snd_soc_dai_link' in this case? Do I need two dai_links with the same
> 'cpu_dai_name' and 'platform_name'?
>
> Are there examples for such a configuration? I didn't had much luck in
> finding one in the mainline?
>
> Any help would be highly appreciated.  Thanks!

Hi,

Support for multiple CODEC DAIs on the same link has recently been added by 
Benoit. See commit 88bd870f ("ASoC: core: Add initial support for DAI 
multicodec"). You now have the possibility to specify multiple CODEC DAIs in 
the link using the snd_soc_dai_link_component struct.

- Lars

Re: ASoC: How to connect a single CPU DAI to two codecs?

[Sergej Sawazki]

Am 27.09.2014 um 19:17 schrieb Lars-Peter Clausen:
> On 09/27/2014 03:33 PM, Sergej Sawazki wrote:
>> Hello,
>>
>> I'm writing an ALSA SoC machine driver for a board that has two mono 
>> codecs
>> (left and right audio channel). Each codec is controlled over I2C and 
>> has
>> itsown address.Both codecs are connected to the same I2S CPU DAI (as 
>> shown
>> below).
>>
>>      +--------- (adr: 0x1a) -----+
>>      |                           |
>>      |             +--------> codec_1 ----> (left channel audio)
>>      |             |
>>     I2C    I2S ----+
>>      |             |
>>      |             +--------> codec_2 ----> (right channel audio)
>>      |                           |
>>      +--------- (adr: 0x1b) -----+
>>
>> Can someone give me some advice on how to setup the 'snd_soc_card' and
>> 'snd_soc_dai_link' in this case? Do I need two dai_links with the same
>> 'cpu_dai_name' and 'platform_name'?
>>
>> Are there examples for such a configuration? I didn't had much luck in
>> finding one in the mainline?
>>
>> Any help would be highly appreciated.  Thanks!
>
> Hi,
>
> Support for multiple CODEC DAIs on the same link has recently been 
> added by Benoit. See commit 88bd870f ("ASoC: core: Add initial support 
> for DAI multicodec"). You now have the possibility to specify multiple 
> CODEC DAIs in the link using the snd_soc_dai_link_component struct.
>
> - Lars
>
>
Lars, Benoit,

many thanks, 'snd_soc_dai_link_component' works like a charm.

  - Sergej