ARM: shmobile: r8a7794: add I2C DT support

Define the generic R8A7794 parts of the I2C[0-5] device nodes.

Based on the original patch by Koji Matsuoka <koji.matsuoka.xm@renesas.com>.
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

arch/arm/boot/dts/r8a7794.dtsi

@@ -20,6 +20,12 @@ / {
 	#size-cells = <2>;
 
 	aliases {
+		i2c0 = &i2c0;
+		i2c1 = &i2c1;
+		i2c2 = &i2c2;
+		i2c3 = &i2c3;
+		i2c4 = &i2c4;
+		i2c5 = &i2c5;
 		spi0 = &qspi;
 	};
 
@@ -502,6 +508,73 @@ ether: ethernet@ee700000 {
 		status = "disabled";
 	};
 
+	/* The memory map in the User's Manual maps the cores to bus numbers */
+	i2c0: i2c@e6508000 {
+		compatible = "renesas,i2c-r8a7794";
+		reg = <0 0xe6508000 0 0x40>;
+		interrupts = <0 287 IRQ_TYPE_LEVEL_HIGH>;
+		clocks = <&mstp9_clks R8A7794_CLK_I2C0>;
+		power-domains = <&cpg_clocks>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+		status = "disabled";
+	};
+
+	i2c1: i2c@e6518000 {
+		compatible = "renesas,i2c-r8a7794";
+		reg = <0 0xe6518000 0 0x40>;
+		interrupts = <0 288 IRQ_TYPE_LEVEL_HIGH>;
+		clocks = <&mstp9_clks R8A7794_CLK_I2C1>;
+		power-domains = <&cpg_clocks>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+		status = "disabled";
+	};
+
+	i2c2: i2c@e6530000 {
+		compatible = "renesas,i2c-r8a7794";
+		reg = <0 0xe6530000 0 0x40>;
+		interrupts = <0 286 IRQ_TYPE_LEVEL_HIGH>;
+		clocks = <&mstp9_clks R8A7794_CLK_I2C2>;
+		power-domains = <&cpg_clocks>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+		status = "disabled";
+	};
+
+	i2c3: i2c@e6540000 {
+		compatible = "renesas,i2c-r8a7794";
+		reg = <0 0xe6540000 0 0x40>;
+		interrupts = <0 290 IRQ_TYPE_LEVEL_HIGH>;
+		clocks = <&mstp9_clks R8A7794_CLK_I2C3>;
+		power-domains = <&cpg_clocks>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+		status = "disabled";
+	};
+
+	i2c4: i2c@e6520000 {
+		compatible = "renesas,i2c-r8a7794";
+		reg = <0 0xe6520000 0 0x40>;
+		interrupts = <0 19 IRQ_TYPE_LEVEL_HIGH>;
+		clocks = <&mstp9_clks R8A7794_CLK_I2C4>;
+		power-domains = <&cpg_clocks>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+		status = "disabled";
+	};
+
+	i2c5: i2c@e6528000 {
+		compatible = "renesas,i2c-r8a7794";
+		reg = <0 0xe6528000 0 0x40>;
+		interrupts = <0 20 IRQ_TYPE_LEVEL_HIGH>;
+		clocks = <&mstp9_clks R8A7794_CLK_I2C5>;
+		power-domains = <&cpg_clocks>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+		status = "disabled";
+	};
+
 	mmcif0: mmc@ee200000 {
 		compatible = "renesas,mmcif-r8a7794", "renesas,sh-mmcif";
 		reg = <0 0xee200000 0 0x80>;