ARM: shmobile: r8a7794: add QSPI DT support

Define the generic R8A7794 part of the QSPI device node.

Based on original patch by Hisashi Nakamura <hisashi.nakamura.ak@renesas.com>.
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

arch/arm/boot/dts/r8a7794.dtsi

@@ -19,6 +19,10 @@ / {
 	#address-cells = <2>;
 	#size-cells = <2>;
 
+	aliases {
+		spi0 = &qspi;
+	};
+
 	cpus {
 		#address-cells = <1>;
 		#size-cells = <0>;
@@ -537,6 +541,20 @@ sdhi2: sd@ee160000 {
 		status = "disabled";
 	};
 
+	qspi: spi@e6b10000 {
+		compatible = "renesas,qspi-r8a7794", "renesas,qspi";
+		reg = <0 0xe6b10000 0 0x2c>;
+		interrupts = <0 184 IRQ_TYPE_LEVEL_HIGH>;
+		clocks = <&mstp9_clks R8A7794_CLK_QSPI_MOD>;
+		dmas = <&dmac0 0x17>, <&dmac0 0x18>;
+		dma-names = "tx", "rx";
+		power-domains = <&cpg_clocks>;
+		num-cs = <1>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+		status = "disabled";
+	};
+
 	clocks {
 		#address-cells = <2>;
 		#size-cells = <2>;