[PATCH v4 1/3] ARM: dts: aspeed: ast2600evb: Add sdhci node and gpio regulator for A2 evb.

[Steven Lee]

AST2600 A2(or newer) EVB has gpio regulators for toggling signal voltage
between 3.3v and 1.8v, the patch adds sdhci node and gpio regulator in the
new dts file and adds commment for describing the reference design.

Signed-off-by: Steven Lee <steven_lee at aspeedtech.com>
---
 arch/arm/boot/dts/aspeed-ast2600-evb-a2.dts | 98 +++++++++++++++++++++
 1 file changed, 98 insertions(+)
 create mode 100644 arch/arm/boot/dts/aspeed-ast2600-evb-a2.dts

diff --git a/arch/arm/boot/dts/aspeed-ast2600-evb-a2.dts b/arch/arm/boot/dts/aspeed-ast2600-evb-a2.dts
new file mode 100644
index 000000000000..d581e8069a82
--- /dev/null
+++ b/arch/arm/boot/dts/aspeed-ast2600-evb-a2.dts
@@ -0,0 +1,98 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+// Copyright 2021 IBM Corp.
+
+#include "aspeed-ast2600-evb.dts"
+#include <dt-bindings/gpio/gpio.h>
+
+/ {
+	model = "AST2600 A2 EVB";
+	compatible = "aspeed,ast2600";
+
+	vcc_sdhci0: regulator-vcc-sdhci0 {
+		compatible = "regulator-fixed";
+		regulator-name = "SDHCI0 Vcc";
+		regulator-min-microvolt = <3300000>;
+		regulator-max-microvolt = <3300000>;
+		gpios = <&gpio0 168
+			 GPIO_ACTIVE_HIGH>;
+		enable-active-high;
+	};
+
+	vccq_sdhci0: regulator-vccq-sdhci0 {
+		compatible = "regulator-gpio";
+		regulator-name = "SDHCI0 VccQ";
+		regulator-min-microvolt = <1800000>;
+		regulator-max-microvolt = <3300000>;
+		gpios = <&gpio0 169
+			 GPIO_ACTIVE_HIGH>;
+		gpios-states = <1>;
+		states = <3300000 1>,
+			 <1800000 0>;
+	};
+
+	vcc_sdhci1: regulator-vcc-sdhci1 {
+		compatible = "regulator-fixed";
+		regulator-name = "SDHCI1 Vcc";
+		regulator-min-microvolt = <3300000>;
+		regulator-max-microvolt = <3300000>;
+		gpios = <&gpio0 170
+			 GPIO_ACTIVE_HIGH>;
+		enable-active-high;
+	};
+
+	vccq_sdhci1: regulator-vccq-sdhci1 {
+		compatible = "regulator-gpio";
+		regulator-name = "SDHCI1 VccQ";
+		regulator-min-microvolt = <1800000>;
+		regulator-max-microvolt = <3300000>;
+		gpios = <&gpio0 171
+			 GPIO_ACTIVE_HIGH>;
+		gpios-states = <1>;
+		states = <3300000 1>,
+			 <1800000 0>;
+	};
+};
+
+&sdc {
+	status = "okay";
+};
+
+/*
+ * The signal voltage of sdhci0 and sdhci1 on AST2600-A2 EVB is able to be
+ * toggled by GPIO pins.
+ * In the reference design, GPIOV0 of AST2600-A2 EVB is connected to the
+ * power load switch that providing 3.3v to sdhci0 vdd, GPIOV1 is connected to
+ * a 1.8v and a 3.3v power load switch that providing signal voltage to
+ * sdhci0 bus.
+ * If GPIOV0 is active high, sdhci0 is enabled, otherwise, sdhci0 is disabled.
+ * If GPIOV1 is active high, 3.3v power load switch is enabled, sdhci0 signal
+ * voltage is 3.3v, otherwise, 1.8v power load switch will be enabled,
+ * sdhci0 signal voltage becomes 1.8v.
+ * AST2600-A2 EVB also support toggling signal voltage for sdhci1.
+ * The design is the same as sdhci0, it uses GPIOV2 as power-gpio and GPIOV3
+ * as power-switch-gpio.
+ */
+&sdhci0 {
+	status = "okay";
+	bus-width = <4>;
+	max-frequency = <100000000>;
+	sdhci-drive-type = /bits/ 8 <3>;
+	sdhci-caps-mask = <0x7 0x0>;
+	sdhci,wp-inverted;
+	vmmc-supply = <&vcc_sdhci0>;
+	vqmmc-supply = <&vccq_sdhci0>;
+	clk-phase-sd-hs = <7>, <200>;
+};
+
+&sdhci1 {
+	status = "okay";
+	bus-width = <4>;
+	max-frequency = <100000000>;
+	sdhci-drive-type = /bits/ 8 <3>;
+	sdhci-caps-mask = <0x7 0x0>;
+	sdhci,wp-inverted;
+	vmmc-supply = <&vcc_sdhci1>;
+	vqmmc-supply = <&vccq_sdhci1>;
+	clk-phase-sd-hs = <7>, <200>;
+};
+
-- 
2.17.1