Re: [PATCH v2 2/8] dt-bindings: arm: apple: Add apple,pmgr binding

[Krzysztof Kozlowski <krzk@kernel.org>]

On Wed, 27 Oct 2021 at 16:44, Rob Herring <robh@kernel.org> wrote:
>
> On Tue, Oct 26, 2021 at 10:38 PM Hector Martin <marcan@marcan.st> wrote:
> >
> > On 27/10/2021 03.25, Rob Herring wrote:
> > > On Mon, Oct 25, 2021 at 11:47:12PM +0900, Hector Martin wrote:
> > >> +  compatible:
> > >> +    items:
> > >> +      - enum:
> > >> +          - apple,t8103-pmgr
> > >> +          - apple,t8103-minipmgr
> > >> +      - const: apple,pmgr
> > >> +      - const: syscon
> > >> +      - const: simple-mfd
> > >
> > >
> > > 'simple-mfd' means 'there's nothing in this node that any of the child
> > > nodes depend on'. You should be somewhat certain as dropping it later
> > > creates compatibility issues.
> >
> > Hmm, I see simple-mfd turns this into a bus which I guess allows child
> > nodes to be probed without the parent node doing anything special (then
> > we use syscon_node_to_regmap to get the syscon instantiated). Do you
> > have a example use case for doing this without simple-mfd?
>
> Drivers calling of_platform_populate or devm_of_platform_populate.
>
> That of course does mean you need a driver. We could probably make the
> syscon driver call these if needed.
>

Hi Hector,

I thought I mentioned this with your v1, maybe the comment got lost.
We have it for Exynos PMU:
drivers/soc/samsung/exynos-pmu.c
arch/arm/boot/dts/exynos-syscon-restart.dtsi (extending node from
arch/arm/boot/dts/exynos5420.dtsi)
Maybe you can base on that.

Best regards,
Krzysztof