RE: [PATCH] dt-bindings: mxsfb: Exclude i.MX8MQ from power-domains requirement

[Ying Liu]

On Friday, August 11, 2023 3:30 AM Conor Dooley <conor@xxxxxxxxxx> wrote:
> 
> On Wed, Aug 02, 2023 at 11:51:17AM +0200, Guido Günther wrote:
> > Hi,
> > On Sun, Jul 30, 2023 at 09:41:20PM +0300, David Heidelberg wrote:
> > > i.MX8MQ uses as secondary compatible fsl,imx6sx-lcdif, which triggers
> > > requirement of power-domains, thou it's not required.
> > >
> > > Fixes: f62678a77d58 ("dt-bindings: mxsfb: Document
> i.MX8M/i.MX6SX/i.MX6SL power-domains property")
> > >
> > > Signed-off-by: David Heidelberg <david@xxxxxxx>
> > > ---
> > >  .../devicetree/bindings/display/fsl,lcdif.yaml        | 11 +++++++++--
> > >  1 file changed, 9 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
> b/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
> > > index fc11ab5fc465..2d868276b0f9 100644
> > > --- a/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
> > > +++ b/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
> > > @@ -129,8 +129,15 @@ allOf:
> > >                - fsl,imx8mp-lcdif
> > >                - fsl,imx93-lcdif
> > >      then:
> > > -      required:
> > > -        - power-domains
> > > +      if:
> > > +        properties:
> > > +          compatible:
> > > +            not:
> > > +              contains:
> > > +                const: fsl,imx8mq-lcdif
> > > +      then:
> > > +        required:
> > > +          - power-domains
> >
> > We currently enable the mipi power domain for the mipi dphy and nwl
> > bridge only but not for LCDIF itself assuming it's not needed (as there's
> > other outputs LCDIF can drive). I *think* this is correct but maybe
> > Marek or Liu can confirm?
> 
> I'm happy to Ack this, but I've been sitting on it waiting to see if
> Marek or Liu popped up..

I see DCSS and HDMI controller/PHY sit in displaymix in a system
bus diagram(internal only), but LCDIF and MIPI DSI controller/PHY
are not in that mix.  So, it seems that the "gpc_disp" power domain
defined in imx8mq.dtsi supplies power for DCSS and HDMI
controller/PHY only, though nxp,imx8mq-dcss.yaml doesn't even
allow a "power-domains" property...

Assuming that system bus diagram is correct and "gpc_disp" power domain
does supply power for everything in displaymix only:
Reviewed-by: Liu Ying <victor.liu@xxxxxxx>

P.s., there are still a few warnings from dtbs-check, see build log[1].
Hope they can be addressed...

[1] https://gitlab.com/robherring/dt-review-ci/-/jobs/4767324570/artifacts/raw/build-dtbs-1814673.log

Liu Ying