Re: [PATCH 11/13] ARM: dts: stm32: fix LTDC port node on STM32 MCU ad MPU

[Alexandre TORGUE]

Hi Marek

On 4/15/21 3:21 PM, Marek Vasut wrote:
> On 4/15/21 12:10 PM, Alexandre Torgue wrote:
> > Running "make dtbs_check W=1", some warnings are reported concerning
> > LTDC port subnode:
> >
> > /soc/display-controller@5a001000/port:
> > unnecessary #address-cells/#size-cells without "ranges" or child "reg"
> > property
> > /soc/display-controller@5a001000/port: graph node has single child node
> > 'endpoint', #address-cells/#size-cells are not necessary
>
> btw could you retain diffstat on your patches ? It's useful to see which 
> files changed right away.
> [...]
>
> > diff --git a/arch/arm/boot/dts/stm32mp157c-dk2.dts 
> > b/arch/arm/boot/dts/stm32mp157c-dk2.dts
> > index 2bc92ef3aeb9..19ef475a48fc 100644
> > --- a/arch/arm/boot/dts/stm32mp157c-dk2.dts
> > +++ b/arch/arm/boot/dts/stm32mp157c-dk2.dts
> > @@ -82,9 +82,15 @@
> >   };
> >   &ltdc {
> > -    status = "okay";
> > -
> >       port {
> > +        #address-cells = <1>;
> > +        #size-cells = <0>;
> > +
> > +        ltdc_ep0_out: endpoint@0 {
> > +            reg = <0>;
> > +            remote-endpoint = <&sii9022_in>;
> > +        };
> > +
> >           ltdc_ep1_out: endpoint@1 {
> >               reg = <1>;
> >               remote-endpoint = <&dsi_in>;
>
> [...]
>
> > diff --git a/arch/arm/boot/dts/stm32mp15xx-dhcor-avenger96.dtsi 
> > b/arch/arm/boot/dts/stm32mp15xx-dhcor-avenger96.dtsi
> > index 64dca5b7f748..e7f10975cacf 100644
> > --- a/arch/arm/boot/dts/stm32mp15xx-dhcor-avenger96.dtsi
> > +++ b/arch/arm/boot/dts/stm32mp15xx-dhcor-avenger96.dtsi
> > @@ -277,11 +277,7 @@
> >       status = "okay";
> >       port {
> > -        #address-cells = <1>;
> > -        #size-cells = <0>;
> > -
> > -        ltdc_ep0_out: endpoint@0 {
> > -            reg = <0>;
> > +        ltdc_ep0_out: endpoint {
> >               remote-endpoint = <&adv7513_in>;
> >           };
> >       };
>
> I think this is wrong, the AV96 can have two displays connected to two 
> ports of the LTDC, just like DK2 for example.

As for dk2 address/size cells are added only if there are 2 endpoints. 
It is for this reason I moved endpoint0 definition from stm32mp15xx-dkx 
to stm32mp151a-dk1.dts (dk1 has only one endpoint).

Here it's the same, if you have second endpoint then adress/size will 
have to be added.

alex