[PATCH 2/2] ARM: dts: samsung: Add Hardkernel ODROID-U2
From: Josef Schlehofer
Date: Sun Oct 18 2026 - 08:46:02 EST
ODROID-U2 is a single board computer from Hardkernel based on the
Samsung Exynos4412 Prime SoC with 2 GB of LPDDR2 RAM. It is the
predecessor of the ODROID-U3 and shares most of its design:
- microSD card slot and eMMC module socket
- SMSC LAN9730 10/100 Ethernet on HSIC0
- SMSC USB3503A hub on HSIC1 with two USB 2.0 host ports
- micro-HDMI port with CEC
- MAX98090 audio codec with a 3.5 mm headphone jack and an on-board
digital microphone
- MAX77686 PMIC
- 2-pin header for an optional PWM controlled cooling fan
- blue heartbeat LED
Unlike the ODROID-U3, the micro-USB port has no VBUS supply switch, so
it can only work in peripheral mode, and there is no expansion header
with SPI. The 3.5 mm jack is headphone only and the speaker outputs of
the codec are not connected.
Add an initial device tree for the board, based on the ODROID-U3 one,
and update the comments in the common dtsi, as the LDO22 and BUCK8
constraints are now also set by the ODROID-U2.
Also route "HiFi Capture" to "Mixer DAI RX", as on the ODROID-XU3. The
odroid sound card driver adds only the playback routes for boards with
a single CPU DAI, so without it the DPCM capture path to the I2S
back-end is incomplete and recording from the digital microphone fails
with "no backend DAIs enabled for Primary".
Link: https://www.hardkernel.com/shop/odroid-u2/
Link: https://www.hardkernel.com/blog-2/odroid-u2-u-schematics/
Signed-off-by: Josef Schlehofer <pepe.schlehofer@xxxxxxxxx>
---
arch/arm/boot/dts/samsung/Makefile | 1 +
.../dts/samsung/exynos4412-odroid-common.dtsi | 6 +-
.../boot/dts/samsung/exynos4412-odroidu2.dts | 139 ++++++++++++++++++
3 files changed, 143 insertions(+), 3 deletions(-)
create mode 100644 arch/arm/boot/dts/samsung/exynos4412-odroidu2.dts
diff --git a/arch/arm/boot/dts/samsung/Makefile b/arch/arm/boot/dts/samsung/Makefile
index e0143ee8c82d..2a173e4b3e1a 100644
--- a/arch/arm/boot/dts/samsung/Makefile
+++ b/arch/arm/boot/dts/samsung/Makefile
@@ -16,6 +16,7 @@ dtb-$(CONFIG_ARCH_EXYNOS4) += \
exynos4412-i9305.dtb \
exynos4412-itop-elite.dtb \
exynos4412-n710x.dtb \
+ exynos4412-odroidu2.dtb \
exynos4412-odroidu3.dtb \
exynos4412-odroidx.dtb \
exynos4412-odroidx2.dtb \
diff --git a/arch/arm/boot/dts/samsung/exynos4412-odroid-common.dtsi b/arch/arm/boot/dts/samsung/exynos4412-odroid-common.dtsi
index 93ddbd4b0a18..b56b92c78c1d 100644
--- a/arch/arm/boot/dts/samsung/exynos4412-odroid-common.dtsi
+++ b/arch/arm/boot/dts/samsung/exynos4412-odroid-common.dtsi
@@ -414,8 +414,8 @@ ldo21_reg: LDO21 {
ldo22_reg: LDO22 {
/*
- * Only U3 uses it, so let it define the
- * constraints
+ * Only U2 and U3 use it, so let them define
+ * the constraints
*/
regulator-name = "LDO22";
regulator-boot-on;
@@ -486,7 +486,7 @@ buck7_reg: BUCK7 {
buck8_reg: BUCK8 {
/*
* Constraints set by specific board: X,
- * X2 and U3.
+ * X2, U2 and U3.
*/
regulator-name = "BUCK8_2.8V";
};
diff --git a/arch/arm/boot/dts/samsung/exynos4412-odroidu2.dts b/arch/arm/boot/dts/samsung/exynos4412-odroidu2.dts
new file mode 100644
index 000000000000..5cb5f874b562
--- /dev/null
+++ b/arch/arm/boot/dts/samsung/exynos4412-odroidu2.dts
@@ -0,0 +1,139 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Hardkernel's Exynos4412 based ODROID-U2 board device tree source
+ *
+ * Copyright (c) 2014 Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
+ * Copyright (c) 2026 Josef Schlehofer <pepe.schlehofer@xxxxxxxxx>
+ *
+ * Device tree source file for Hardkernel's ODROID-U2 board which is based
+ * on Samsung's Exynos4412 SoC.
+ */
+
+/dts-v1/;
+#include <dt-bindings/leds/common.h>
+#include "exynos4412-odroid-common.dtsi"
+#include "exynos4412-prime.dtsi"
+
+/ {
+ model = "Hardkernel ODROID-U2 board based on Exynos4412";
+ compatible = "hardkernel,odroid-u2", "samsung,exynos4412", "samsung,exynos4";
+
+ aliases {
+ ethernet = ðernet;
+ };
+
+ memory@40000000 {
+ device_type = "memory";
+ reg = <0x40000000 0x7ff00000>;
+ };
+
+ leds {
+ compatible = "gpio-leds";
+
+ led1 {
+ function = LED_FUNCTION_HEARTBEAT;
+ color = <LED_COLOR_ID_BLUE>;
+ gpios = <&gpc1 0 GPIO_ACTIVE_LOW>;
+ default-state = "on";
+ linux,default-trigger = "heartbeat";
+ };
+ };
+
+ fan0: pwm-fan {
+ compatible = "pwm-fan";
+ pwms = <&pwm 0 10000 0>;
+ #cooling-cells = <2>;
+ cooling-levels = <0 102 170 230>;
+ };
+};
+
+&adc {
+ vdd-supply = <&ldo10_reg>;
+ /* Nothing connected to ADC inputs, keep it disabled */
+};
+
+/* Supply for LAN9730/SMSC95xx */
+&buck8_reg {
+ regulator-name = "BUCK8_P3V3";
+ regulator-min-microvolt = <3300000>;
+ regulator-max-microvolt = <3300000>;
+};
+
+&cpu_thermal {
+ cooling-maps {
+ map0 {
+ trip = <&cpu_alert1>;
+ cooling-device = <&cpu0 9 9>, <&cpu1 9 9>,
+ <&cpu2 9 9>, <&cpu3 9 9>,
+ <&fan0 1 2>;
+ };
+ map1 {
+ trip = <&cpu_alert2>;
+ cooling-device = <&cpu0 15 15>, <&cpu1 15 15>,
+ <&cpu2 15 15>, <&cpu3 15 15>,
+ <&fan0 2 3>;
+ };
+ map2 {
+ trip = <&cpu_alert0>;
+ cooling-device = <&fan0 0 1>;
+ };
+ };
+};
+
+&ehci {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ phys = <&exynos_usbphy 2>, <&exynos_usbphy 3>;
+ phy-names = "hsic0", "hsic1";
+
+ ethernet: ethernet@2 {
+ compatible = "usb424,9730";
+ reg = <2>;
+ local-mac-address = [00 00 00 00 00 00]; /* Filled in by a bootloader */
+ };
+};
+
+&hdmicec {
+ needs-hpd;
+};
+
+/* No VBUS supply switch on the micro-USB port */
+&hsotg {
+ dr_mode = "peripheral";
+};
+
+/* VDDQ for MSHC (eMMC card) */
+&ldo22_reg {
+ regulator-name = "LDO22_VDDQ_MMC4_2.8V";
+ regulator-min-microvolt = <2800000>;
+ regulator-max-microvolt = <2800000>;
+};
+
+&mshc_0 {
+ vqmmc-supply = <&ldo22_reg>;
+};
+
+&pwm {
+ pinctrl-0 = <&pwm0_out>;
+ pinctrl-names = "default";
+ samsung,pwm-outputs = <0>;
+ status = "okay";
+};
+
+&sound {
+ model = "Odroid-U2";
+ samsung,audio-widgets =
+ "Headphone", "Headphone Jack",
+ "Microphone", "DMIC";
+ audio-routing = "Headphone Jack", "HPL",
+ "Headphone Jack", "HPR",
+ "DMICL", "DMIC",
+ "DMICR", "DMIC",
+ "Mixer DAI RX", "HiFi Capture";
+};
+
+&usb3503 {
+ clock-names = "refclk";
+ clocks = <&pmu_system_controller 0>;
+ refclk-frequency = <24000000>;
+};
--
2.54.0 (Apple Git-157)