Hi On Wed, 2022-06-15 at 10:15 -0700, Krzysztof Kozlowski wrote: > On 15/06/2022 09:10, Max Krummenacher wrote: > > Hi > > > > On Tue, Jun 14, 2022 at 9:22 AM Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote: > > > > > > Hi Rob, > > > > > > On Mon, Jun 13, 2022 at 9:15 PM Rob Herring <robh@xxxxxxxxxx> wrote: > > > > On Thu, Jun 09, 2022 at 05:08:46PM +0200, Max Krummenacher wrote: > > > > > From: Max Krummenacher <max.krummenacher@xxxxxxxxxxx> > > > > > > > > > > its power enable by using a regulator. > > > > > > > > > > The currently implemented PM domain providers are all specific to > > > > > a particular system on chip. > > > > > > > > Yes, power domains tend to be specific to an SoC... 'power-domains' is > > > > supposed to be power islands in a chip. Linux 'PM domains' can be > > > > anything... > > > > I don't see why such power islands should be restricted to a SoC. You can > > build the exact same idea on a PCB or even more modular designs. > > In the SoC these power islands are more-or-less defined. These are real > regions gated by some control knob. > > Calling few devices on a board "power domain" does not make it a power > domain. There is no grouping, there is no control knob. > > Aren't you now re-implementing regulator supplies? How is this different > than existing supplies? I believe the biggest difference between power-domains and regulator-supplies lays in the former being driver agnostic while the later is driver specific. Meaning with power-domains one can just add such arbitrary structure to the device tree without any further driver specific changes/handling required. While with regulator-supplies each and every driver actually needs to have driver specific handling thereof added. Or do I miss anything? We are really trying to model something where a single GPIO pin (via a GPIO regulator or whatever) can control power to a variety of on-board peripherals. And, of course, we envision runtime PM actually making use of it e.g. when doing suspend/resume. > Best regards, > Krzysztof Cheers Marcel
