[PATCH v1 1/7] dt-bindings: display: add STM32 LTDC driver

On 01/16/2017 09:30 PM, Laurent Pinchart wrote:

Hi Yannick,

Thank you for the patch.

On Monday 16 Jan 2017 14:28:58 Yannick Fertre wrote:

quoted

Signed-off-by: Yannick Fertre <redacted>
---
 .../devicetree/bindings/display/st,ltdc.txt        | 57 ++++++++++++++++++
 1 file changed, 57 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/st,ltdc.txt

diff --git a/Documentation/devicetree/bindings/display/st,ltdc.txt

b/Documentation/devicetree/bindings/display/st,ltdc.txt new file mode
100644
index 0000000..20e89da

--- /dev/null
+++ b/Documentation/devicetree/bindings/display/st,ltdc.txt

@@ -0,0 +1,57 @@
+* STMicroelectronics STM32 lcd-tft display controller
+
+- st-display-subsystem: Master device for DRM sub-components
+  This device must be the parent of all the sub-components and is

responsible
+  of bind them.

Why do you need this ? At a quick glance the ltdc node should be enough.

Hi Laurent,
To prepare next device upstream of dsi, we need a master node 
"st-display-subsystem" and a sub node "st,ltdc". It's the same kind of 
node than st,stih4xx.

quoted

+  Required properties:
+  - compatible: "st,display-subsystem"
+  - ranges: to allow probing of subdevices
+
+- ltdc_host: lcd-tft display controller host
+  must be a sub-node of st-display-subsystem
+  Required properties:
+  - compatible: "st,ltdc"
+  - reg: Physical base address of the IP registers and length of memory
mapped region.
+  - clocks: from common clock binding: handle hardware IP needed clocks,
the
+    number of clocks may depend of the SoC type.
+    See ../clocks/clock-bindings.txt for details.
+  - clock-names: names of the clocks listed in clocks property in the same
+    order.

You need to define the required/optional clocks with their names here. If they
vary depending on the SoC, the DT bindings document need to list them for each
SoC.

Ok, I'll push news bindings with pack V2.

quoted

+  - resets: resets to be used by the device
+    See ../reset/reset.txt for details.
+  - reset-names: names of the resets listed in resets property in the same
+    order.
+  Required nodes:
+    - Video port for RGB output.
+
+Example:
+
+/ {
+	...
+	soc {
+	...
+		st-display-subsystem {
+			compatible = "st,display-subsystem";
+			#address-cells = <1>;
+			#size-cells = <1>;
+			ranges;
+			dma-ranges;
+
+			ltdc_host: stm32-ltdc at 40016800 {
+				compatible = "st,ltdc";
+				reg = <0x40016800 0x200>;
+				interrupts = <88>, <89>;
+				resets = <&rcc 314>;
+				clocks = <&rcc 1 8>;
+				clock-names = "clk-lcd";
+				status = "disabled";
+
+				port {
+					ltdc_out_rgb: endpoint {
+					};
+				};
+			};
+		};
+	...
+	};
+};