media: dt-bindings: Add jpeg enc device tree node document

Add jpeg enc device tree node document.
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Tomasz Figa <tfiga@chromium.org>
Signed-off-by: Xia Jiang <xia.jiang@mediatek.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

Documentation/devicetree/bindings/media/mediatek-jpeg-encoder.txt

+* MediaTek JPEG Encoder
+
+MediaTek JPEG Encoder is the JPEG encode hardware present in MediaTek SoCs
+
+Required properties:
+- compatible : "mediatek,mt2701-jpgenc"
+  followed by "mediatek,mtk-jpgenc"
+- reg : physical base address of the JPEG encoder registers and length of
+  memory mapped region.
+- interrupts : interrupt number to the interrupt controller.
+- clocks: device clocks, see
+  Documentation/devicetree/bindings/clock/clock-bindings.txt for details.
+- clock-names: must contain "jpgenc". It is the clock of JPEG encoder.
+- power-domains: a phandle to the power domain, see
+  Documentation/devicetree/bindings/power/power_domain.txt for details.
+- mediatek,larb: must contain the local arbiters in the current SoCs, see
+  Documentation/devicetree/bindings/memory-controllers/mediatek,smi-larb.txt
+  for details.
+- iommus: should point to the respective IOMMU block with master port as
+  argument, see Documentation/devicetree/bindings/iommu/mediatek,iommu.txt
+  for details.
+
+Example:
+	jpegenc: jpegenc@1500a000 {
+		compatible = "mediatek,mt2701-jpgenc",
+			     "mediatek,mtk-jpgenc";
+		reg = <0 0x1500a000 0 0x1000>;
+		interrupts = <GIC_SPI 141 IRQ_TYPE_LEVEL_LOW>;
+		clocks =  <&imgsys CLK_IMG_VENC>;
+		clock-names = "jpgenc";
+		power-domains = <&scpsys MT2701_POWER_DOMAIN_ISP>;
+		mediatek,larb = <&larb2>;
+		iommus = <&iommu MT2701_M4U_PORT_JPGENC_RDMA>,
+			 <&iommu MT2701_M4U_PORT_JPGENC_BSDMA>;
+	};