Re: [PATCH 1/3] dt-bindings: mt8173: Fix mdp device tree

From: Rob Herring
Date: Wed Apr 19 2017 - 17:35:50 EST


On Thu, Apr 13, 2017 at 03:33:05PM +0800, Minghsiu Tsai wrote:
> If the mdp_* nodes are under an mdp sub-node, their corresponding
> platform device does not automatically get its iommu assigned properly.
>
> Fix this by moving the mdp component nodes up a level such that they are
> siblings of mdp and all other SoC subsystems. This also simplifies the
> device tree.

It may simplify the DT, but it also breaks compatibility with old DT.
Not sure if that's a problem on Mediatek platforms, but please be
explicit here that you are breaking compatibility and why that is okay.

>
> Signed-off-by: Daniel Kurtz <djkurtz@xxxxxxxxxxxx>
> Signed-off-by: Minghsiu Tsai <minghsiu.tsai@xxxxxxxxxxxx>

Should this have Daniel as the author?

>
> ---
> Documentation/devicetree/bindings/media/mediatek-mdp.txt | 12 +++---------
> 1 file changed, 3 insertions(+), 9 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/media/mediatek-mdp.txt b/Documentation/devicetree/bindings/media/mediatek-mdp.txt
> index 4182063..0d03e3a 100644
> --- a/Documentation/devicetree/bindings/media/mediatek-mdp.txt
> +++ b/Documentation/devicetree/bindings/media/mediatek-mdp.txt
> @@ -2,7 +2,7 @@
>
> Media Data Path is used for scaling and color space conversion.
>
> -Required properties (controller (parent) node):
> +Required properties (controller node):
> - compatible: "mediatek,mt8173-mdp"
> - mediatek,vpu: the node of video processor unit, see
> Documentation/devicetree/bindings/media/mediatek-vpu.txt for details.
> @@ -32,21 +32,16 @@ Required properties (DMA function blocks, child node):
> for details.
>
> Example:
> -mdp {
> - compatible = "mediatek,mt8173-mdp";
> - #address-cells = <2>;
> - #size-cells = <2>;
> - ranges;
> - mediatek,vpu = <&vpu>;
> -
> mdp_rdma0: rdma@14001000 {
> compatible = "mediatek,mt8173-mdp-rdma";
> + "mediatek,mt8173-mdp";
> reg = <0 0x14001000 0 0x1000>;
> clocks = <&mmsys CLK_MM_MDP_RDMA0>,
> <&mmsys CLK_MM_MUTEX_32K>;
> power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
> iommus = <&iommu M4U_PORT_MDP_RDMA0>;
> mediatek,larb = <&larb0>;
> + mediatek,vpu = <&vpu>;
> };
>
> mdp_rdma1: rdma@14002000 {
> @@ -106,4 +101,3 @@ mdp {
> iommus = <&iommu M4U_PORT_MDP_WROT1>;
> mediatek,larb = <&larb4>;
> };
> -};
> --
> 1.9.1
>