Hi Takashi,
While working on implementing the probes features in SOF using a separate card for the probe DAI links, I noticed that calling snd_soc_register_card() results in incrementing the usage_count for the device that registers the card by 2 and it is not decremented until the card is freed.
Is this the expected behaviour? Typically, we register a separate platform device for the Intel machines which in turn register the card and none of them ever enable runtime PM. So this has no impact on the parent device's runtime PM status.
I'd like to avoid creating a separate platform device just to register the card if possible while also enabling runtime PM . But when I do this today, the device cannot enter runtime suspend at all. Could you please shed some light on this?
Thanks, Ranjani