V4L: s5c73m3: Add device tree support

This patch adds the V4L2 asynchronous subdev registration and
device tree support. Common clock API is used to control the
sensor master clock from within the subdev driver.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
---
Changes since v1:
 - added missing ret assignment on clk_get failure,
 - fixed error paths in probe(),
 - changed clock name to cis_extclk as specified in the datasheet,
 - separate properties used for the XSHUTDOWN, STANDBY GPIOs,
 - multiple correctiond in the binding documentation (improved
   description of data-lanes and clock-frequency properties).

1 files changed, 95 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/media/samsung-s5c73m3.txt b/Documentation/devicetree/bindings/media/samsung-s5c73m3.txt
new file mode 100644
index 00000000000..6d6c0b6476d
--- /dev/null
+++ b/Documentation/devicetree/bindings/media/samsung-s5c73m3.txt
@@ -0,0 +1,95 @@
+Samsung S5C73M3 8Mp camera ISP
+------------------------------
+
+The S5C73M3 camera ISP supports MIPI CSI-2 and parallel (ITU-R BT.656) video
+data busses. The I2C bus is the main control bus and additionally the SPI bus
+is used, mostly for transferring the firmware to and from the device. Two
+slave device nodes corresponding to these control bus interfaces are required
+and should be placed under respective bus controller nodes.
+
+I2C slave device node
+---------------------
+
+Required properties:
+
+- compatible	    : "samsung,s5c73m3";
+- reg		    : I2C slave address of the sensor;
+- vdd-int-supply    : digital power supply (1.2V);
+- vdda-supply	    : analog power supply (1.2V);
+- vdd-reg-supply    : regulator input power supply (2.8V);
+- vddio-host-supply : host I/O power supply (1.8V to 2.8V);
+- vddio-cis-supply  : CIS I/O power supply (1.2V to 1.8V);
+- vdd-af-supply	    : lens power supply (2.8V);
+- xshutdown-gpios   : specifier of GPIO connected to the XSHUTDOWN pin;
+- standby-gpios     : specifier of GPIO connected to the STANDBY pin;
+- clocks	    : contains the sensor's CIS_EXTCLK clock specifier;
+- clock-names	    : contains "cis_extclk" entry;
+
+Optional properties:
+
+- clock-frequency   : the frequency at which the "cis_extclk" clock should be
+		      configured to operate, in Hz; if this property is not
+		      specified default 24 MHz value will be used.
+
+The common video interfaces bindings (see video-interfaces.txt) should be used
+to specify link from the S5C73M3 to an external image data receiver. The S5C73M3
+device node should contain one 'port' child node with an 'endpoint' subnode for
+this purpose. The data link from a raw image sensor to the S5C73M3 can be
+similarly specified, but it is optional since the S5C73M3 ISP and a raw image
+sensor are usually inseparable and form a hybrid module.
+
+Following properties are valid for the endpoint node(s):
+
+endpoint subnode
+----------------
+
+- data-lanes : (optional) specifies MIPI CSI-2 data lanes as covered in
+  video-interfaces.txt. This sensor doesn't support data lane remapping
+  and physical lane indexes in subsequent elements of the array should
+  be only consecutive ascending values.
+
+SPI device node
+---------------
+
+Required properties:
+
+- compatible	    : "samsung,s5c73m3";
+
+For more details see description of the SPI busses bindings
+(../spi/spi-bus.txt) and bindings of a specific bus controller.
+
+Example:
+
+i2c@138A000000 {
+	...
+	s5c73m3@3c {
+		compatible = "samsung,s5c73m3";
+		reg = <0x3c>;
+		vdd-int-supply = <&buck9_reg>;
+		vdda-supply = <&ldo17_reg>;
+		vdd-reg-supply = <&cam_io_reg>;
+		vddio-host-supply = <&ldo18_reg>;
+		vddio-cis-supply = <&ldo9_reg>;
+		vdd-af-supply = <&cam_af_reg>;
+		clock-frequency = <24000000>;
+		clocks = <&clk 0>;
+		clock-names = "cis_extclk";
+		reset-gpios = <&gpf1 3 1>;
+		standby-gpios = <&gpm0 1 1>;
+		port {
+			s5c73m3_ep: endpoint {
+				remote-endpoint = <&csis0_ep>;
+				data-lanes = <1 2 3 4>;
+			};
+		};
+	};
+};
+
+spi@1392000 {
+	...
+	s5c73m3_spi: s5c73m3 {
+		compatible = "samsung,s5c73m3";
+		reg = <0>;
+		...
+	};
+};