[PATCH v4 15/23] ASoC: soc-core: Identify 'no_pcm' DAI links for DPCM

Sameer Pujar spujar at nvidia.com
Tue Jun 30 10:03:27 CEST 2020



On 6/30/2020 11:37 AM, Kuninori Morimoto wrote:
> External email: Use caution opening links or attachments
>
>
> Hi Sameer
>
>> PCM devices are created for dai links with 'no-pcm' flag as '0'.
>> Such DAI links have CPU component which implement pcm_construct()
>> and pcm_destruct() callbacks. Based on this, current patch exposes
>> a helper function to identify such components and populate 'no_pcm'
>> flag for DPCM DAI link.
>>
>> This helps to have BE<->BE component links where PCM devices need
>> not be created for CPU components involved in the links.
>>
>> Signed-off-by: Sameer Pujar <spujar at nvidia.com>
>> ---
> (snip)
>> +bool soc_component_is_pcm(struct snd_soc_dai_link_component *dlc)
>> +{
>> +     struct snd_soc_component *component;
>> +     struct snd_soc_dai *dai;
>> +
>> +     for_each_component(component) {
>> +             if (!component->driver)
>> +                     continue;
>> +
>> +             for_each_component_dais(component, dai) {
>> +                     if (!dai->name || !dlc->dai_name)
>> +                             continue;
>> +
>> +                     if (strcmp(dai->name, dlc->dai_name))
>> +                             continue;
>> +
>> +                     if (component->driver->pcm_construct)
>> +                             return true;
>> +             }
>> +     }
>> +
>> +     return false;
>> +}
> At least my CPU driver doesn't use component:pcm_construct
> but is using DAI:pcm_new for some reasons.
> I'm not sure checking DAI:pcm here is enough, or not...

OK. If adding DAI:pcm_new above here is not sufficient, then a flag can 
be used to describe FE component? or is there a better alternative?
>
> Thank you for your help !!
>
> Best regards
> ---
> Kuninori Morimoto



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