[PATCH] ARM: dts: imx6qdl-dhcom: Move IPU iomux node from PDK2 to SoM file

[Marek Vasut]

On 8/12/22 15:25, Krzysztof Kozlowski wrote:
> On 12/08/2022 15:03, Christoph Niedermaier wrote:
>> To have a variant (imx6dl/imx6q) independent access to the IPU
>> iomux node move them to the SoM file.
> 
> There is no such variant using them, so the "possibility" is not a
> reason for such change. The change by itself, without proper users, does
> not make any sense.

I think it does make sense to move the IPUv3 RGB/DPI interface pinmux 
description from PDK2 carrier board DT into the common SoM DTSI, but for 
a different reason entirely.

The SoM specification states there is such an interface on the SoM pins:

"
https://wiki.dh-electronics.com/images/2/2e/DOC_DHCOM-Standard-Specification_R01_2016-11-17.pdf

Page 20

5.1.14 RGB Display
The DHCOM standard provides a parallel 24-bit RGB interface for driving 
displays.
"

And from what I can tell, for a carrier board to be compatible with the 
SoM standard above, those pins have to be used as the RGB/DPI interface 
or not used at all.

So rather than duplicate the pinmux settings in every carrier board DT, 
better move/deduplicate them into the SoM DTSI.

But it seems the commit message should be updated to reflect that.

btw. there are also downstream DTOs which do reference that pinmux 
settings label, but maybe those DTOs are not really interesting with 
regards to this specific change.