[PATCH v2 1/8] dt-bindings: Document STM32 DCMI bindings

[Hugues Fruchet <hugues.fruchet@st.com>]

This adds documentation of device tree bindings for the STM32 DCMI
(Digital Camera Memory Interface).

Signed-off-by: Hugues Fruchet <hugues.fruchet@st.com>
---
 .../devicetree/bindings/media/st,stm32-dcmi.txt    | 85 ++++++++++++++++++++++
 1 file changed, 85 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/media/st,stm32-dcmi.txt

diff --git a/Documentation/devicetree/bindings/media/st,stm32-dcmi.txt b/Documentation/devicetree/bindings/media/st,stm32-dcmi.txt
new file mode 100644
index 0000000..8180f63
--- /dev/null
+++ b/Documentation/devicetree/bindings/media/st,stm32-dcmi.txt
@@ -0,0 +1,85 @@
+STMicroelectronics STM32 Digital Camera Memory Interface (DCMI)
+
+Required properties:
+- compatible: "st,stm32-dcmi"
+- reg: physical base address and length of the registers set for the device
+- interrupts: should contain IRQ line for the DCMI
+- clocks: list of clock specifiers, corresponding to entries in
+          the clock-names property
+- clock-names: must contain "mclk", which is the DCMI peripherial clock
+- resets: reference to a reset controller
+- reset-names: see Documentation/devicetree/bindings/reset/st,stm32-rcc.txt
+
+DCMI supports a single port node with parallel bus. It should contain one
+'port' child node with child 'endpoint' node. Please refer to the bindings
+defined in Documentation/devicetree/bindings/media/video-interfaces.txt.
+
+Example:
+
+Device node example
+-------------------
+	dcmi: dcmi@50050000 {
+		compatible = "st,stm32-dcmi";
+		reg = <0x50050000 0x400>;
+		interrupts = <78>;
+		resets = <&rcc STM32F4_AHB2_RESET(DCMI)>;
+		clocks = <&rcc 0 STM32F4_AHB2_CLOCK(DCMI)>;
+		clock-names = "mclk";
+		pinctrl-names = "default";
+		pinctrl-0 = <&dcmi_pins>;
+		dmas = <&dma2 1 1 0x414 0x3>;
+		dma-names = "tx";
+		status = "disabled";
+	};
+
+Board setup example
+-------------------
+This example is extracted from STM32F429-EVAL board devicetree.
+Please note that on this board, the camera sensor reset & power-down
+line level are inverted (so reset is active high and power-down is
+active low).
+
+/ {
+	[...]
+	clocks {
+		clk_ext_camera: clk-ext-camera {
+			#clock-cells = <0>;
+			compatible = "fixed-clock";
+			clock-frequency = <24000000>;
+		};
+	};
+	[...]
+};
+
+&dcmi {
+	status = "okay";
+
+	port {
+		dcmi_0: endpoint@0 {
+			remote-endpoint = <&ov2640_0>;
+			bus-width = <8>;
+			hsync-active = <0>;
+			vsync-active = <0>;
+			pclk-sample = <1>;
+		};
+	};
+};
+
+&i2c@1 {
+	[...]
+	ov2640: camera@30 {
+		compatible = "ovti,ov2640";
+		reg = <0x30>;
+		resetb-gpios = <&stmpegpio 2 GPIO_ACTIVE_HIGH>;
+		pwdn-gpios = <&stmpegpio 0 GPIO_ACTIVE_LOW>;
+		clocks = <&clk_ext_camera>;
+		clock-names = "xvclk";
+		status = "okay";
+
+		port {
+			ov2640_0: endpoint {
+				remote-endpoint = <&dcmi_0>;
+			};
+		};
+	};
+};
-- 
1.9.1