[media] dt-bindings: Add Renesas R-Car FCP DT bindings

The FCP is a companion module of video processing modules in the Renesas
R-Car Gen3 SoCs. It provides data compression and decompression, data
caching, and conversion of AXI transactions in order to reduce the
memory bandwidth.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

Documentation/devicetree/bindings/media/renesas,fcp.txt

+Renesas R-Car Frame Compression Processor (FCP)
+-----------------------------------------------
+
+The FCP is a companion module of video processing modules in the Renesas R-Car
+Gen3 SoCs. It provides data compression and decompression, data caching, and
+conversion of AXI transactions in order to reduce the memory bandwidth.
+
+There are three types of FCP: FCP for Codec (FCPC), FCP for VSP (FCPV) and FCP
+for FDP (FCPF). Their configuration and behaviour depend on the module they
+are paired with. These DT bindings currently support the FCPV only.
+
+ - compatible: Must be one or more of the following
+
+   - "renesas,r8a7795-fcpv" for R8A7795 (R-Car H3) compatible 'FCP for VSP'
+   - "renesas,fcpv" for generic compatible 'FCP for VSP'
+
+   When compatible with the generic version, nodes must list the
+   SoC-specific version corresponding to the platform first, followed by the
+   family-specific and/or generic versions.
+
+ - reg: the register base and size for the device registers
+ - clocks: Reference to the functional clock
+
+
+Device node example
+-------------------
+
+	fcpvd1: fcp@fea2f000 {
+		compatible = "renesas,r8a7795-fcpv", "renesas,fcpv";
+		reg = <0 0xfea2f000 0 0x200>;
+		clocks = <&cpg CPG_MOD 602>;
+	};