Kuninori Morimoto <kuninori.morimoto.gx@xxxxxxxxxxx> writes: > Hi Aidan > > Thank you for your patch > >> Some DAIs have multiple system clock sources, which can be chosen >> using the "clk_id" argument to snd_soc_dai_set_sysclk(). Currently >> this is hardcoded to 0 when using simple cards, but that choice is >> not always suitable. >> >> Add the "system-clock-id" property to allow selecting a different >> clock ID on a per-DAI basis. >> >> To simplify the logic on DPCM cards, add a dummy "asoc_simple_dai" >> instance and use that for the dummy components on DPCM links. This >> ensures that when we're iterating over DAIs in the PCM runtime there >> is always a matching "asoc_simple_dai" we can dereference. >> >> Signed-off-by: Aidan MacDonald <aidanmacdonald.0x0@xxxxxxxxx> >> --- > > I think adding "system-clock-id" and adding "dummy asoc_simple_dai" are > different topics. This patch should be separated into 2 patches. Sounds good to me. > And I couldn't understand the reason why we need to add dummy asoc_simple_dai. > In my understanding, we don't parse DT for dummy connection. > Which process are you talking about specifically here? > > This ensures that when we're iterating over DAIs in the PCM runtime there > is always a matching "asoc_simple_dai" we can dereference. > - > Thank you for your help !! > > Best regards > --- > Kuninori Morimoto DPCM DAI links have some real DAIs and one dummy DAI. Each real DAI has an asoc_simple_dai associated with it to contain the information parsed from the DT. The dummy DAI does not have an asoc_simple_dai. I'm adding a dummy asoc_simple_dai for these dummy DAIs to make the mapping of snd_soc_dai to asoc_simple_dai 1-to-1. The non 1-to-1 mapping is problematic, because if I have a snd_soc_dai and want to look up a simple-card property I would need to check if the matching asoc_simple_dai exists first, and have a special case for DPCM dummy DAIs. With a 1-to-1 mapping I can handle all DAIs the same way. Regards, Aidan