On Tue, Sep 6, 2022 at 11:31 AM Mark Kettenis <mark.kettenis@xxxxxxxxx> wrote: > Another argument for having sub-nodes is that the firmware actually > exposes *two* GPIO controllers. For now we only support the "master" > PMU GPIOs, but there also is a "slave" PMU GPIO controller that uses a > separate set of SMC "keys". We currently don't need any of the pins > on the "slave", so we don't expose it in the DT yet. That sounds backward, like we don't expose device X as DT node because $OS doesn't use it yet. DT should just expose (by nodes or other ways) all hardware that exist or at least all hardware we know about no matter what $OS is using. FWIW I think nodes makes most sense because no doubt for example the RTC is a separate hardware unit somewhere, and so is the GPIO. The fact that it is hidden behind a software abstraction doesn't change the fact that the HW definitely has these discrete units. Yours, Linus Walleij
