Re: [PATCH 1/2] dt-bindings: wkup-m3-ipc: Add vtt toggle bindings

From: Drew Fustini
Date: Sat Apr 09 2022 - 16:36:21 EST


On Sat, Apr 09, 2022 at 06:25:24PM +0200, Krzysztof Kozlowski wrote:
> On 09/04/2022 06:51, Drew Fustini wrote:
> > Document the Wakeup M3 IPC properties that can be used to toggle the VTT
> > regulator during low power mode transitions.
> >
>
> (...)
>
> > @@ -51,6 +61,15 @@ properties:
> > mbox_wkupm3 child node.
> > maxItems: 1
> >
> > + ti,needs-vtt-toggle:
> > + type: boolean
> > + description: boards requires VTT toggling during suspend/resume
> > +
> > + ti,vtt-gpio-pin:
> > + $ref: /schemas/types.yaml#/definitions/uint32
> > + description: pin on the GPIO0 module used for VTT toggle
> > + maxItems: 1
>
> No need for maxItems, it's a single uint32. You could add "maximum" if
> you know the constraints for the value.

Thank you for letting me know.

> Do you actually need two properties (bool + pin)? A case of
> "ti,vtt-gpio-pin" without the "ti,needs-vtt-toggle" is valid?

You raise a good point. In fact, the driver does nothing useful in the
case of "ti,needs-vtt-toggle" without "ti,vtt-gpio-pin". Therefore, I
will remove the "ti,needs-vtt-toggle" property.

>
> The other way looks wrong, so you need to add a dependency (see
> example-schema).
>
>
> Best regards,
> Krzysztof

Thank you,
Drew