Re: [RFC 02/11] dt-bindings: power: amlogic, meson-gx-pwrc: Add SM1 bindings

From: Martin Blumenstingl
Date: Tue Jul 02 2019 - 20:57:25 EST


Hi Neil,

On Mon, Jul 1, 2019 at 12:48 PM Neil Armstrong <narmstrong@xxxxxxxxxxxx> wrote:
[...]
> +General Purpose Power Controller
> +--------------------------------
>
> +The Amlogic SM1 SoCs embeds a General Purpose Power Controller used
> +to control the power domain for, at least, the USB PHYs and PCIe
> +peripherals.
AFAIK each binding document should only describe one IP block.
this one seems to be new / different

should it get it's own file?
also should it be a .yaml binding?

> +
> +Device Tree Bindings:
> +---------------------
> +
> +Required properties:
> +- compatible: should be one of the following :
> + - "amlogic,meson-sm1-pwrc" for the Meson SM1 SoCs
> +- #power-domain-cells: should be 0
> +- amlogic,hhi-sysctrl: phandle to the HHI sysctrl node
> +
> +Parent node should have the following properties :
> +- compatible: "amlogic,meson-gx-ao-sysctrl", "syscon", "simple-mfd"
> +- reg: base address and size of the AO system control register space.
> +
> +
> +Example:
> +-------
> +
> +ao_sysctrl: sys-ctrl@0 {
> + compatible = "amlogic,meson-gx-ao-sysctrl", "syscon", "simple-mfd";
> + reg = <0x0 0x0 0x0 0x100>;
> +
> + pwrc: power-controller {
> + compatible = "amlogic,meson-sm1-pwrc";
> + #power-domain-cells = <1>;
> + amlogic,hhi-sysctrl = <&hhi>;
> + };
> +};
I'm not sure that we want to mix HHI and AO power domains in one driver again
back in March I asked a few questions about modelling the power
domains and Kevin explained that we can implement them hierarchical:
[0]
unfortunately I didn't have the time to work on this - however, now
that we implement a new driver: should we follow this hierarchical
approach?


Martin


[0] http://lists.infradead.org/pipermail/linux-amlogic/2019-March/010512.html