Hi Rob,
On 9/5/23 20:14, Rob Herring wrote:
On Mon, Sep 04, 2023 at 01:58:15PM +0200, Sascha Hauer wrote:
Add rockchip,io-domains property to the Rockchip pinctrl driver. This
list of phandles points to the IO domain device(s) the pins of the
pinctrl driver are supplied from.
Is there an actual need for multiple IO devices with multiple pinctrl
blocks? If not, you don't need a property, just lookup the IO domain
node by compatible.
Yes. There can be multiple IO domain devices on Rockchip SoCs and we
typically have only one pinctrl controller. Each pinctrl "pin" (for a
lack of the appropriate term to use here) belongs to one domain of one
of the IO domain controller/device.
However what I don't like here is that we do not explicit this link
between the pinctrl "pin" and the IO domain controller it belongs to
(even less so on which domain of the IO domain controller, which to be
fair we do not represent in the DT at the moment except through a
phandle property in the IO domain controller, c.f.
https://elixir.bootlin.com/linux/latest/source/Documentation/devicetree/bindings/power/rockchip-io-domain.yaml#L84).
Cheers,
Quentin
