Messages in this thread | | | Date | Thu, 24 Feb 2022 18:39:56 +0000 | From | Mark Brown <> | Subject | Re: [RFC 00/10] add support for fwnode in i2c mux system and sfp |
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On Thu, Feb 24, 2022 at 08:14:51PM +0200, Sakari Ailus wrote: > On Thu, Feb 24, 2022 at 03:33:12PM +0000, Mark Brown wrote:
> > I believe clocks are also potentially problematic for similar reasons > > (ACPI wants to handle those as part of the device level power management > > and/or should have native abstractions for them, and I think we also > > have board file provisions that work well for them and are less error > > prone than translating into an abstract data structure).
> Per ACPI spec, what corresponds to clocks and regulators in DT is handled > through power resources. This is generally how things work in ACPI based > systems but there are cases out there where regulators and/or clocks are > exposed to software directly. This concerns e.g. camera sensors and lens > voice coils on some systems while rest of the devices in the system are > powered on and off the usual ACPI way.
But note crucially that when these things are controlled by the OS they are enumerated via some custom mechanism that is *not* _DSD properties - the issue is with the firmware interface, not with using the relevant kernel APIs in the client or provider devices. [unhandled content-type:application/pgp-signature] | |