[media] s5p-fimc: Add device tree based sensors registration

The sensor (I2C and/or SPI client) devices are instantiated by their
corresponding control bus drivers. Since the I2C client's master clock
is often provided by a video bus receiver (host interface) or other
than I2C/SPI controller device, the drivers of those client devices
are not accessing hardware in their driver's probe() callback. Instead,
after enabling clock, the host driver calls back into a sub-device
when it wants to activate them. This pattern is used by some in-tree
drivers and this patch also uses it for DT case. This patch is intended
as a first step for adding device tree support to the S5P/Exynos SoC
camera drivers. The second one is adding support for asynchronous
sub-devices registration and clock control from sub-device driver
level. The bindings shall not change when asynchronous probing support
is added.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

Documentation/devicetree/bindings/media/samsung-fimc.txt

@@ -72,18 +72,95 @@ Optional properties:
   writeback input.
 
 
+'parallel-ports' node
+---------------------
+
+This node should contain child 'port' nodes specifying active parallel video
+input ports. It includes camera A and camera B inputs. 'reg' property in the
+port nodes specifies data input - 0, 1 indicates input A, B respectively.
+
+Optional properties
+
+- samsung,camclk-out : specifies clock output for remote sensor,
+		       0 - CAM_A_CLKOUT, 1 - CAM_B_CLKOUT;
+
+Image sensor nodes
+------------------
+
+The sensor device nodes should be added to their control bus controller (e.g.
+I2C0) nodes and linked to a port node in the csis or the parallel-ports node,
+using the common video interfaces bindings, defined in video-interfaces.txt.
+The implementation of this bindings requires clock-frequency property to be
+present in the sensor device nodes.
+
 Example:
 
 	aliases {
 		fimc0 = &fimc_0;
 	};
 
+	/* Parallel bus IF sensor */
+	i2c_0: i2c@13860000 {
+		s5k6aa: sensor@3c {
+			compatible = "samsung,s5k6aafx";
+			reg = <0x3c>;
+			vddio-supply = <...>;
+
+			clock-frequency = <24000000>;
+			clocks = <...>;
+			clock-names = "mclk";
+
+			port {
+				s5k6aa_ep: endpoint {
+					remote-endpoint = <&fimc0_ep>;
+					bus-width = <8>;
+					hsync-active = <0>;
+					vsync-active = <1>;
+					pclk-sample = <1>;
+				};
+			};
+		};
+	};
+
+	/* MIPI CSI-2 bus IF sensor */
+	s5c73m3: sensor@0x1a {
+		compatible = "samsung,s5c73m3";
+		reg = <0x1a>;
+		vddio-supply = <...>;
+
+		clock-frequency = <24000000>;
+		clocks = <...>;
+		clock-names = "mclk";
+
+		port {
+			s5c73m3_1: endpoint {
+				data-lanes = <1 2 3 4>;
+				remote-endpoint = <&csis0_ep>;
+			};
+		};
+	};
+
 	camera {
 		compatible = "samsung,fimc", "simple-bus";
 		#address-cells = <1>;
 		#size-cells = <1>;
 		status = "okay";
 
+		/* parallel camera ports */
+		parallel-ports {
+			/* camera A input */
+			port@0 {
+				reg = <0>;
+				fimc0_ep: endpoint {
+					remote-endpoint = <&s5k6aa_ep>;
+					bus-width = <8>;
+					hsync-active = <0>;
+					vsync-active = <1>;
+					pclk-sample = <1>;
+				};
+			};
+		};
+
 		fimc_0: fimc@11800000 {
 			compatible = "samsung,exynos4210-fimc";
 			reg = <0x11800000 0x1000>;
@@ -95,6 +172,15 @@ Example:
 			compatible = "samsung,exynos4210-csis";
 			reg = <0x11880000 0x1000>;
 			interrupts = <0 78 0>;
+			/* camera C input */
+			port@3 {
+				reg = <3>;
+				csis0_ep: endpoint {
+					remote-endpoint = <&s5c73m3_ep>;
+					data-lanes = <1 2 3 4>;
+					samsung,csis-hs-settle = <12>;
+				};
+			};
 		};
 	};