arm64: dts: ti: am64-phyboard-electra: Add overlay to enable a GPIO fan

The phyBOARD-Electra has a GPIO fan header. This overlay enables the fan
header and sets the fan to turn on at 65C.

Signed-off-by: Nathan Morrisson <[e-mail]>
Reviewed-by: Wadim Egorov <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Nishanth Menon <[e-mail]>

arch/arm64/boot/dts/ti/Makefile

···
 dtb-$(CONFIG_ARCH_K3) += k3-am642-hummingboard-t-pcie.dtb
 dtb-$(CONFIG_ARCH_K3) += k3-am642-hummingboard-t-usb3.dtb
 dtb-$(CONFIG_ARCH_K3) += k3-am642-phyboard-electra-rdk.dtb
+dtb-$(CONFIG_ARCH_K3) += k3-am642-phyboard-electra-gpio-fan.dtbo
 dtb-$(CONFIG_ARCH_K3) += k3-am642-sk.dtb
 dtb-$(CONFIG_ARCH_K3) += k3-am642-tqma64xxl-mbax4xxl.dtb
 dtb-$(CONFIG_ARCH_K3) += k3-am64-tqma64xxl-mbax4xxl-sdcard.dtbo
···
 	k3-am62x-sk-csi2-tevi-ov5640.dtbo
 k3-am642-evm-icssg1-dualemac-dtbs := \
 	k3-am642-evm.dtb k3-am642-evm-icssg1-dualemac.dtbo
+k3-am642-phyboard-electra-gpio-fan-dtbs := \
+	k3-am642-phyboard-electra-rdk.dtb k3-am642-phyboard-electra-gpio-fan.dtbo
 k3-am642-tqma64xxl-mbax4xxl-sdcard-dtbs := \
 	k3-am642-tqma64xxl-mbax4xxl.dtb k3-am64-tqma64xxl-mbax4xxl-sdcard.dtbo
 k3-am642-tqma64xxl-mbax4xxl-wlan-dtbs := \
···
 DTC_FLAGS_k3-am62a7-sk += -@
 DTC_FLAGS_k3-am62p5-sk += -@
 DTC_FLAGS_k3-am642-evm += -@
+DTC_FLAGS_k3-am642-phyboard-electra-rdk += -@
 DTC_FLAGS_k3-am642-tqma64xxl-mbax4xxl += -@
 DTC_FLAGS_k3-am6548-iot2050-advanced-m2 += -@
 DTC_FLAGS_k3-am68-sk-base-board += -@

arch/arm64/boot/dts/ti/k3-am642-phyboard-electra-gpio-fan.dtso

···
+// SPDX-License-Identifier: GPL-2.0-only OR MIT
+/*
+ * Copyright (C) 2024 PHYTEC America LLC
+ * Author: Nathan Morrisson <[e-mail]>
+ */
+
+/dts-v1/;
+/plugin/;
+
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/thermal/thermal.h>
+#include "k3-pinctrl.h"
+
+&{/} {
+	fan: gpio-fan {
+		compatible = "gpio-fan";
+		gpio-fan,speed-map = <0 0 8600 1>;
+		gpios = <&main_gpio0 28 GPIO_ACTIVE_LOW>;
+		#cooling-cells = <2>;
+		pinctrl-names = "default";
+		pinctrl-0 = <&gpio_fan_pins_default>;
+	};
+};
+
+&main_pmx0 {
+	gpio_fan_pins_default: gpio-fan-default-pins {
+		pinctrl-single,pins = <
+			AM64X_IOPAD(0x070, PIN_OUTPUT, 7) /* (V18) GPMC0_AD13.GPIO0_28 */
+		>;
+	};
+};
+
+&thermal_zones {
+	main0_thermal: main0-thermal {
+		trips {
+			main0_thermal_trip0: main0-thermal-trip {
+				temperature = <65000>;  /* millicelsius */
+				hysteresis = <2000>;    /* millicelsius */
+				type = "active";
+			};
+		};
+
+		cooling-maps {
+			map0 {
+				trip = <&main0_thermal_trip0>;
+				cooling-device = <&fan THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
+			};
+		};
+	};
+};