arm64: dts: renesas: rzg3s-smarc-som: Enable SDHI2

Add SDHI2 to RZ/G3S Smarc SoM.  SDHI2 pins are multiplexed with SCIF1,
SSI0, IRQ0, IRQ1.  The selection b/w SDHI2 and SCIF1, SSI0, IRQ0, IRQ1
is done with a switch button.  To be able to select b/w these a
compilation flag has been added (SW_SD2_EN) at the moment being
instantiated to select SDHI2.
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20231016105344.294096-2-claudiu.beznea.uj@bp.renesas.comSigned-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

arch/arm64/boot/dts/renesas/rzg3s-smarc-som.dtsi

@@ -13,14 +13,21 @@
  * @SW_SD0_DEV_SEL:
  *	0 - SD0 is connected to eMMC
  *	1 - SD0 is connected to uSD0 card
+ * @SW_SD2_EN:
+ *	0 - SCIF1, SSI0, IRQ0, IRQ1 connected to SoC
+ *	1 - SD2 is connected to SoC
  */
 #define SW_SD0_DEV_SEL	1
+#define SW_SD2_EN	1
 
 / {
 	compatible = "renesas,rzg3s-smarcm", "renesas,r9a08g045s33", "renesas,r9a08g045";
 
 	aliases {
 		mmc0 = &sdhi0;
+#if SW_SD2_EN
+		mmc2 = &sdhi2;
+#endif
 	};
 
 	chosen {
@@ -63,6 +70,15 @@ reg_1p8v: regulator1 {
 		regulator-always-on;
 	};
 #endif
+
+	vcc_sdhi2: regulator2 {
+		compatible = "regulator-fixed";
+		regulator-name = "SDHI2 Vcc";
+		regulator-min-microvolt = <3300000>;
+		regulator-max-microvolt = <3300000>;
+		gpios = <&pinctrl RZG2L_GPIO(8, 1) GPIO_ACTIVE_HIGH>;
+		enable-active-high;
+	};
 };
 
 &extal_clk {
@@ -100,6 +116,17 @@ &sdhi0 {
 };
 #endif
 
+#if SW_SD2_EN
+&sdhi2 {
+	pinctrl-0 = <&sdhi2_pins>;
+	pinctrl-names = "default";
+	vmmc-supply = <&vcc_sdhi2>;
+	bus-width = <4>;
+	max-frequency = <50000000>;
+	status = "okay";
+};
+#endif
+
 &pinctrl {
 	sdhi0_pins: sd0 {
 		data {
@@ -139,4 +166,26 @@ sdhi0_emmc_pins: sd0-emmc {
 		       "SD0_CLK", "SD0_CMD", "SD0_RST#";
 		power-source = <1800>;
 	};
+
+	sdhi2_pins: sd2 {
+		data {
+			pins = "P11_2", "P11_3", "P12_0", "P12_1";
+			input-enable;
+		};
+
+		ctrl {
+			pins = "P11_1";
+			input-enable;
+		};
+
+		mux {
+			pinmux = <RZG2L_PORT_PINMUX(11, 0, 8)>, /* SD2_CLK */
+				 <RZG2L_PORT_PINMUX(11, 1, 8)>, /* SD2_CMD */
+				 <RZG2L_PORT_PINMUX(11, 2, 8)>, /* SD2_DATA0 */
+				 <RZG2L_PORT_PINMUX(11, 3, 8)>, /* SD2_DATA1 */
+				 <RZG2L_PORT_PINMUX(12, 0, 8)>, /* SD2_DATA2 */
+				 <RZG2L_PORT_PINMUX(12, 1, 8)>, /* SD2_DATA3 */
+				 <RZG2L_PORT_PINMUX(14, 1, 7)>; /* SD2_CD# */
+		};
+	};
 };