Hi Philipp, CK,
Please see my comments inline.
On Thu, Nov 19, 2015 at 2:34 AM, Philipp Zabel p.zabel@pengutronix.de wrote:
From: CK Hu ck.hu@mediatek.com
Add device tree binding documentation for the display subsystem in Mediatek MT8173 SoCs.
Signed-off-by: CK Hu ck.hu@mediatek.com Signed-off-by: Philipp Zabel p.zabel@pengutronix.de Acked-by: Rob Herring robh@kernel.org
Changes since v5:
- Updated DISP_MUTEX description
- Fixed DSI and DPI documentation path
.../bindings/display/mediatek/mediatek,disp.txt | 183 +++++++++++++++++++++ .../bindings/display/mediatek/mediatek,dpi.txt | 35 ++++ .../bindings/display/mediatek/mediatek,dsi.txt | 53 ++++++ 3 files changed, 271 insertions(+) create mode 100644 Documentation/devicetree/bindings/display/mediatek/mediatek,disp.txt create mode 100644 Documentation/devicetree/bindings/display/mediatek/mediatek,dpi.txt create mode 100644 Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.txt
diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,disp.txt b/Documentation/devicetree/bindings/display/mediatek/mediatek,disp.txt new file mode 100644 index 0000000..a311019 --- /dev/null +++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,disp.txt @@ -0,0 +1,183 @@ +Mediatek display subsystem +==========================
+The Mediatek display subsystem consists of various DISP function blocks in the +MMSYS register space. The connections between them can be configured by output +and input selectors in the MMSYS_CONFIG register space. Pixel clock and start +of frame signal are distributed to the other function blocks by a DISP_MUTEX +function block.
+All DISP device tree nodes must be siblings to the central MMSYS_CONFIG node. +For a description of the MMSYS_CONFIG binding, see +Documentation/devicetree/bindings/arm/mediatek/mediatek,mmsys.txt.
+DISP function blocks +====================
+A display stream starts at a source function block that reads pixel data from +memory and ends with a sink function block that drives pixels on a display +interface, or writes pixels back to memory. All DISP function blocks have +their own register space, interrupt, and clock gate. The blocks that can +access memory additionally have to list the IOMMU and local arbiter they are +connected to.
+For a description of the display interface sink function blocks, see +Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.txt and +Documentation/devicetree/bindings/display/mediatek/mediatek,dpi.txt.
+Required properties (all function blocks): +- compatible: "mediatek,<chip>-disp-<function>", one of
"mediatek,<chip>-disp-ovl" - overlay (4 layers, blending, csc)"mediatek,<chip>-disp-rdma" - read DMA / line buffer"mediatek,<chip>-disp-wdma" - write DMA"mediatek,<chip>-disp-color" - color processor"mediatek,<chip>-disp-aal" - adaptive ambient light controller"mediatek,<chip>-disp-gamma" - gamma correction"mediatek,<chip>-disp-ufoe" - data compression engine"mediatek,<chip>-dsi" - DSI controller, see mediatek,dsi.txt"mediatek,<chip>-dpi" - DPI controller, see mediatek,dpi.txt"mediatek,<chip>-disp-mutex" - display mutex"mediatek,<chip>-disp-od" - overdrive+- reg: Physical base address and length of the function block register space +- interrupts: The interrupt signal from the function block.
Do all the blocks have only one interrupt signal?
+- clocks: device clocks
- See Documentation/devicetree/bindings/clock/clock-bindings.txt for details.
What about clock-names? Also all required clocks for particular compatible strings should be listed in documentation,
+- compatible: "mediatek,<chip>-ddp"
Is this a rebase error? compatible property was already described few lines above and also missing description.
+Required properties (DMA function blocks): +- compatible: Should be one of
"mediatek,<chip>-disp-ovl""mediatek,<chip>-disp-rdma""mediatek,<chip>-disp-wdma"
Perhaps these 3 could also have some short description like the ones listed above?
+- larb: Should contain a phandle pointing to the local arbiter device as defined
- in Documentation/devicetree/bindings/soc/mediatek/mediatek,smi-larb.txt
+- iommus: required a iommu node
Maybe rewrite to: "Should point to respective IOMMU block as defined in <path to IOMMU binding documentation>"?
Best regards, Tomasz