[PATCH] arm64: dts: ti: k3-am68-phyboard-izar: Add pwm fan

[PATCH] arm64: dts: ti: k3-am68-phyboard-izar: Add pwm fan

[Dominik Haller]

Add an overlay to control the pwm fan[0] that comes with the kit.

[0] https://www.sepa-europe.com/en/2023/06/16/axial-fan-lf40p/

Signed-off-by: Dominik Haller <d.haller@phytec.de>
---
 arch/arm64/boot/dts/ti/Makefile               |  6 +-
 .../dts/ti/k3-am68-phyboard-izar-pwm-fan.dtso | 74 +++++++++++++++++++
 2 files changed, 79 insertions(+), 1 deletion(-)
 create mode 100644 arch/arm64/boot/dts/ti/k3-am68-phyboard-izar-pwm-fan.dtso

diff --git a/arch/arm64/boot/dts/ti/Makefile b/arch/arm64/boot/dts/ti/Makefile
index 371f9a043fe5..bf03d895aed8 100644
--- a/arch/arm64/boot/dts/ti/Makefile
+++ b/arch/arm64/boot/dts/ti/Makefile
@@ -173,7 +173,10 @@ k3-am68-phyboard-izar-lvds-ph128800t006-dtbs := k3-am68-phyboard-izar.dtb \
 	k3-am68-phyboard-izar-lvds-ph128800t006.dtbo
 dtb-$(CONFIG_ARCH_K3) += k3-am68-phyboard-izar-peb-av-15.dtb
 k3-am68-phyboard-izar-peb-av-15-dtbs := k3-am68-phyboard-izar.dtb \
-        k3-am68-phyboard-izar-peb-av-15.dtbo
+	k3-am68-phyboard-izar-peb-av-15.dtbo
+dtb-$(CONFIG_ARCH_K3) += k3-am68-phyboard-izar-pwm-fan.dtb
+k3-am68-phyboard-izar-pwm-fan-dtbs := k3-am68-phyboard-izar.dtb \
+	k3-am68-phyboard-izar-pwm-fan.dtbo
 dtb-$(CONFIG_ARCH_K3) += k3-am68-sk-base-board.dtb
 dtb-$(CONFIG_ARCH_K3) += k3-am68-sk-base-board-pcie1-ep.dtbo
 dtb-$(CONFIG_ARCH_K3) += k3-j721s2-common-proc-board.dtb
@@ -387,6 +390,7 @@ dtb- += k3-am625-beagleplay-csi2-ov5640.dtb \
 	k3-am642-tqma64xxl-mbax4xxl-wlan.dtb \
 	k3-am68-phyboard-izar-lvds-ph128800t006.dtb \
 	k3-am68-phyboard-izar-peb-av-15.dtb \
+	k3-am68-phyboard-izar-pwm-fan.dtb \
 	k3-am68-sk-base-board-csi2-dual-imx219.dtb \
 	k3-am68-sk-base-board-pcie1-ep.dtb \
 	k3-am69-sk-csi2-dual-imx219.dtb \
diff --git a/arch/arm64/boot/dts/ti/k3-am68-phyboard-izar-pwm-fan.dtso b/arch/arm64/boot/dts/ti/k3-am68-phyboard-izar-pwm-fan.dtso
new file mode 100644
index 000000000000..8c1a51216a90
--- /dev/null
+++ b/arch/arm64/boot/dts/ti/k3-am68-phyboard-izar-pwm-fan.dtso
@@ -0,0 +1,74 @@
+// SPDX-License-Identifier: GPL-2.0-only OR MIT
+/*
+ * Copyright (C) 2026 PHYTEC Messtechnik GmbH
+ * Author: Dominik Haller <d.haller@phytec.de>
+ */
+
+/dts-v1/;
+/plugin/;
+
+#include <dt-bindings/pwm/pwm.h>
+#include "k3-pinctrl.h"
+
+&{/} {
+	pwmfan: pwm-fan {
+		compatible = "pwm-fan";
+		pinctrl-names = "default";
+		pinctrl-0 = <&main_pwmfan_default_pins>;
+		#cooling-cells = <2>;
+		cooling-levels = <0 90 150 255>;
+		/* frequency needs to be the same as lvds backlight */
+		pwms = <&main_ehrpwm0 0 44000 PWM_POLARITY_INVERTED>;
+	};
+};
+
+&main_pmx0 {
+	main_pwmfan_default_pins: main-pwmfan-default-pins {
+		pinctrl-single,pins = <
+			J721S2_IOPAD(0x0cc, PIN_OUTPUT, 5) /* (AE27) SPI0_CS0.EHRPWM0_A */
+		>;
+	};
+};
+
+&main_ehrpwm0 {
+	status = "okay";
+};
+
+&main3_thermal {
+	trips {
+		cpu_low: cpu-low {
+			hysteresis = <3000>;
+			temperature = <55000>;
+			type = "active";
+		};
+
+		cpu_med: cpu-med {
+			hysteresis = <3000>;
+			temperature = <60000>;
+			type = "active";
+		};
+
+		cpu_high: cpu-high {
+			hysteresis = <3000>;
+			temperature = <65000>;
+			type = "active";
+		};
+	};
+
+	cooling-maps {
+		map1 {
+			cooling-device = <&pwmfan 1 1>;
+			trip = <&cpu_low>;
+		};
+
+		map2 {
+			cooling-device = <&pwmfan 2 2>;
+			trip = <&cpu_med>;
+		};
+
+		map3 {
+			cooling-device = <&pwmfan 3 3>;
+			trip = <&cpu_high>;
+		};
+	};
+};
-- 
2.43.0