On Thu, 16 Apr 2020 07:52:45 +0200, Sridharan, Ranjani wrote: > > 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? It's not clear how you see the things. Which device are you looking at? Typically a card object points to two different devices, one is the real device that the chip belongs to (card->dev), and another the own device object for managing the device files (card.card_dev). And in general, snd_soc_card_register() or snd_card_register() don't manipulate the runtime PM stuff by itself at all. thanks, Takashi
