On Wed, May 14, 2014 at 02:06:10PM +0200, Arnd Bergmann wrote:

> The way I see things moving forward for ACPI is to add a standard way to
> name things (GPIOs, IRQs, DMAs, ...) so we can have a generic 'give me
> a pointer to the X object for this device' for each subsystem we want to
> have it for. Note that this would probably not be a combined interface
> across subsystems though.

And indeed we already have that interface in the kernel for most APIs
newer than GPIOs so in implementation terms this normally boils down to
adding an ACPI backend for looking things up.