ARM: dts: exynos: Add support for Samsung Klimt WiFi

Klimt WiFi has the product name Samsung Galaxy Tab S 8.4".  Board is
based on Exynos 5420, and has similar hardware to Chagall WiFi, but
with a smaller battery, smaller screen and another touchscreen
controller.

The device tree added here contains support for:

- UART access through a micro-usb cable with 619 kOhm between ID & GND
- Accessing the internal eMMC storage
- Accessing an external SD card
- USB, after configuration it is possible to ssh into the device
  through a usb cable

Signed-off-by: Henrik Grimler <henrik@grimler.se>
Link: https://lore.kernel.org/r/20220124131241.29946-3-henrik@grimler.se
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>

arch/arm/boot/dts/Makefile

@@ -222,6 +222,7 @@ dtb-$(CONFIG_ARCH_EXYNOS5) += \
 	exynos5420-peach-pit.dtb \
 	exynos5420-smdk5420.dtb \
 	exynos5420-chagall-wifi.dtb \
+	exynos5420-klimt-wifi.dtb \
 	exynos5422-odroidhc1.dtb \
 	exynos5422-odroidxu3.dtb \
 	exynos5422-odroidxu3-lite.dtb \

arch/arm/boot/dts/exynos5420-klimt-wifi.dts

@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Samsung's Exynos5420 Klimt WiFi board device tree source
+ *
+ * Copyright (c) 2012-2013 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com
+ * Copyright (c) 2022 Henrik Grimler
+ */
+
+/dts-v1/;
+#include "exynos5420-galaxy-tab-common.dtsi"
+
+/ {
+	model = "Samsung Klimt WiFi based on Exynos5420";
+	compatible = "samsung,klimt-wifi", "samsung,exynos5420", \
+		     "samsung,exynos5";
+};
+
+&ldo15_reg {
+	/* Unused */
+	regulator-name = "VDD_LDO15";
+	regulator-min-microvolt = <3300000>;
+	regulator-max-microvolt = <3300000>;
+};
+
+&ldo17_reg {
+	regulator-name = "VDD_VCI_3V0";
+	regulator-min-microvolt = <3000000>;
+	regulator-max-microvolt = <3000000>;
+
+	regulator-state-mem {
+		regulator-off-in-suspend;
+	};
+};
+
+&ldo28_reg {
+	regulator-name = "VDD3_1V8";
+	regulator-min-microvolt = <1800000>;
+	regulator-max-microvolt = <1800000>;
+
+	regulator-state-mem {
+		regulator-off-in-suspend;
+	};
+};
+
+&ldo29_reg {
+	regulator-name = "VDDR_1V6";
+	regulator-min-microvolt = <1600000>;
+	regulator-max-microvolt = <1600000>;
+
+	regulator-state-mem {
+		regulator-off-in-suspend;
+	};
+};
+
+&ldo31_reg {
+	/* Unused */
+	regulator-name = "VDD_LDO31";
+	regulator-min-microvolt = <1800000>;
+	regulator-max-microvolt = <1800000>;
+};
+
+&ldo32_reg {
+	regulator-name = "VDD_TSP_1V8";
+	regulator-min-microvolt = <1800000>;
+	regulator-max-microvolt = <1800000>;
+
+	regulator-state-mem {
+		regulator-off-in-suspend;
+	};
+};
+
+&mmc_2 {
+	sd-uhs-sdr104;
+};