ARM: dts: stm32: Add DHCOM based PicoITX board

Add DT for DH PicoITX unit, which is a bare-bones carrier board for
the DHCOM. The board has ethernet port, USB, CAN, LEDs and a custom
board-to-board expansion connector.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Patrick Delaunay <patrick.delaunay@st.com>
Cc: linux-stm32@st-md-mailman.stormreply.com
To: linux-arm-kernel@lists.infradead.org
Signed-off-by: Alexandre Torgue <alexandre.torgue@st.com>

arch/arm/boot/dts/Makefile

@@ -1066,6 +1066,7 @@ dtb-$(CONFIG_ARCH_STM32) += \
 	stm32mp157a-iot-box.dtb \
 	stm32mp157a-stinger96.dtb \
 	stm32mp157c-dhcom-pdk2.dtb \
+	stm32mp157c-dhcom-picoitx.dtb \
 	stm32mp157c-dk2.dtb \
 	stm32mp157c-ed1.dtb \
 	stm32mp157c-ev1.dtb \

arch/arm/boot/dts/stm32mp157c-dhcom-picoitx.dts

+// SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
+/*
+ * Copyright (C) 2020 Marek Vasut <marex@denx.de>
+ *
+ * DHCOM STM32MP1 variant:
+ * DHCM-STM32MP157C-C065-R102-F0819-SPI-E-CAN2-SD-RTC-T-DSI-I-01D2
+ * DHCOM PCB number: 587-200 or newer
+ * PicoITX PCB number: 487-600 or newer
+ */
+/dts-v1/;
+
+#include "stm32mp157.dtsi"
+#include "stm32mp15xc.dtsi"
+#include "stm32mp15xx-dhcom-som.dtsi"
+#include "stm32mp15xx-dhcom-picoitx.dtsi"
+
+/ {
+	model = "DH electronics STM32MP157C DHCOM PicoITX";
+	compatible = "dh,stm32mp157c-dhcom-picoitx", "dh,stm32mp157c-dhcom-som",
+		     "st,stm32mp157";
+};
+
+&m_can1 {
+	pinctrl-names = "default", "sleep";
+	pinctrl-0 = <&m_can1_pins_a>;
+	pinctrl-1 = <&m_can1_sleep_pins_a>;
+	status = "okay";
+};
+
+&m_can2 {
+	pinctrl-names = "default", "sleep";
+	pinctrl-0 = <&m_can2_pins_a>;
+	pinctrl-1 = <&m_can2_sleep_pins_a>;
+	status = "okay";
+};

arch/arm/boot/dts/stm32mp15xx-dhcom-picoitx.dtsi

+// SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
+/*
+ * Copyright (C) 2020 Marek Vasut <marex@denx.de>
+ */
+
+#include <dt-bindings/input/input.h>
+#include <dt-bindings/pwm/pwm.h>
+
+/ {
+	aliases {
+		serial0 = &uart4;
+		serial1 = &usart3;
+		serial2 = &uart8;
+	};
+
+	chosen {
+		stdout-path = "serial0:115200n8";
+	};
+
+	led {
+		compatible = "gpio-leds";
+
+		led-0 {
+			label = "yellow:led";
+			gpios = <&gpioi 3 GPIO_ACTIVE_HIGH>;
+			default-state = "off";
+		};
+	};
+};
+
+&adc {
+	status = "disabled";
+};
+
+&dac {
+	status = "disabled";
+};
+
+&gpioa {
+	/*
+	 * NOTE: The USB Port on the PicoITX needs a PWR_EN signal to enable
+	 * port power. This signal should be handled by USB power sequencing
+	 * in order to turn on port power when USB bus is powered up, but so
+	 * far there is no such functionality.
+	 */
+	usb-port-power {
+		gpio-hog;
+		gpios = <13 GPIO_ACTIVE_LOW>;
+		output-low;
+		line-name = "usb-port-power";
+	};
+};
+
+&gpioc {
+	gpio-line-names = "", "", "", "",
+			  "", "", "In1", "",
+			  "", "", "", "",
+			  "", "", "", "";
+};
+
+&gpiod {
+	gpio-line-names = "", "", "", "",
+			  "", "", "", "",
+			  "", "", "", "Out1",
+			  "Out2", "", "", "";
+};
+
+&gpiog {
+	gpio-line-names = "In2", "", "", "",
+			  "", "", "", "",
+			  "", "", "", "",
+			  "", "", "", "";
+};
+
+&i2c2 {	/* On board-to-board connector (optional) */
+	pinctrl-names = "default";
+	pinctrl-0 = <&i2c2_pins_a>;
+	i2c-scl-rising-time-ns = <185>;
+	i2c-scl-falling-time-ns = <20>;
+	status = "okay";
+	/* spare dmas for other usage */
+	/delete-property/dmas;
+	/delete-property/dma-names;
+};
+
+&i2c5 {	/* On board-to-board connector */
+	pinctrl-names = "default";
+	pinctrl-0 = <&i2c5_pins_a>;
+	i2c-scl-rising-time-ns = <185>;
+	i2c-scl-falling-time-ns = <20>;
+	status = "okay";
+	/* spare dmas for other usage */
+	/delete-property/dmas;
+	/delete-property/dma-names;
+};
+
+&usart3 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&usart3_pins_a>;
+	status = "okay";
+};
+
+&uart8 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&uart8_pins_a &uart8_rtscts_pins_a>;
+	status = "okay";
+};
+
+&usbh_ehci {
+	phys = <&usbphyc_port0>;
+	status = "okay";
+};
+
+&usbh_ohci {
+	phys = <&usbphyc_port0>;
+	status = "okay";
+};
+
+&usbotg_hs {
+	dr_mode = "otg";
+	pinctrl-0 = <&usbotg_hs_pins_a>;
+	pinctrl-names = "default";
+	phy-names = "usb2-phy";
+	phys = <&usbphyc_port1 0>;
+	vbus-supply = <&vbus_otg>;
+	status = "okay";
+};
+
+&usbphyc {
+	status = "okay";
+};
+
+&usbphyc_port0 {
+	phy-supply = <&vdd_usb>;
+	vdda1v1-supply = <&reg11>;
+	vdda1v8-supply = <&reg18>;
+};
+
+&usbphyc_port1 {
+	phy-supply = <&vdd_usb>;
+	vdda1v1-supply = <&reg11>;
+	vdda1v8-supply = <&reg18>;
+};