[alsa-devel] How to create a proc entry for an ASoc codec?

[Liam Girdwood]

On Fri, 2014-04-11 at 10:16 +0100, Lin, Mengdong wrote:
> Hi,
> 
>  
> 
> How to create a proc entry for an ASoc codec under the sound card?
> 
>  
> 
> We hope to create an proc entry for an I2S codec
> under /proc/asound/cardx, to debug the codec status at runtime.
> 
>  
> 
> So after the machine driver calls snd_soc_register_card(&soc_card), I
> calls snd_card_proc_new(soc_card .snd_card, ….) 
> 
> But no codec entry is created although dmesg shows this function
> succeeds.
 
> 
> How ASoC creates the proc entries such as ‘id’ for the sound card?
> 
You should see this :-

cat /proc/asound/card0/id 
broadwellrt286

ASoC exposes sound card specific data under the sysfs entry for the
device. e.g. 

ls /sys/bus/platform/devices/broadwell-audio/
Capture PCM/  driver/       modalias      Offload1/     sound/        System PCM/   
Codec/        Loopback PCM/ Offload0/     power/        subsystem/    uevent 

Liam