On Wed, 2017-04-19 at 16:35 -0500, Rob Herring wrote: > 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. > I will add the following description for more information. " Although it fixes iommu assignment issue, it also break compatibility with old device tree, so driver patch[1] is needed to iterate over sibling mdp device nodes, not child ones, to keep driver work properly. In mtk_mdp_probe() Old: for_each_child_of_node(dev->of_node, node) New: for_each_child_of_node(dev->of_node->parent, node) [1]https://patchwork.kernel.org/patch/9678833/ " > > > > Signed-off-by: Daniel Kurtz <djkurtz@xxxxxxxxxxxx> > > Signed-off-by: Minghsiu Tsai <minghsiu.tsai@xxxxxxxxxxxx> > > Should this have Daniel as the author? This patch is provided by Daniel, so I keep he is the author. I just split his patch into two parts. One is dts only, and the other is for driver. I also provide another patch to modify dts bindings according to this patch. > > > > > --- > > 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 > >