This is an example on how to enable the fan on top of RPi's official PoE hat. Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@xxxxxxx> --- Changes since v1: - Update patch to use 2 pwm cells arch/arm/boot/dts/bcm2711-rpi-4-b.dts | 54 +++++++++++++++++++++++++++ 1 file changed, 54 insertions(+) diff --git a/arch/arm/boot/dts/bcm2711-rpi-4-b.dts b/arch/arm/boot/dts/bcm2711-rpi-4-b.dts index 09a1182c2936..361db82619a4 100644 --- a/arch/arm/boot/dts/bcm2711-rpi-4-b.dts +++ b/arch/arm/boot/dts/bcm2711-rpi-4-b.dts @@ -5,6 +5,7 @@ #include "bcm283x-rpi-usb-peripheral.dtsi" #include <dt-bindings/reset/raspberrypi,firmware-reset.h> +#include <dt-bindings/pwm/raspberrypi,firmware-pwm.h> / { compatible = "raspberrypi,4-model-b", "brcm,bcm2711"; @@ -68,6 +69,54 @@ sd_vcc_reg: sd_vcc_reg { enable-active-high; gpio = <&expgpio 6 GPIO_ACTIVE_HIGH>; }; + + fan: pwm-fan { + compatible = "pwm-fan"; + cooling-levels = <0 50 150 255>; + #cooling-cells = <2>; + pwms = <&fwpwm RASPBERRYPI_FIRMWARE_PWM_POE 80000>; + }; + + thermal-zones { + cpu_thermal: cpu-thermal { + trips { + threshold: trip-point@0 { + temperature = <45000>; + hysteresis = <5000>; + type = "active"; + }; + + target: trip-point@1 { + temperature = <50000>; + hysteresis = <2000>; + type = "active"; + }; + + cpu_hot: cpu_hot@0 { + temperature = <55000>; + hysteresis = <2000>; + type = "active"; + }; + }; + + cooling-maps { + map0 { + trip = <&threshold>; + cooling-device = <&fan 0 1>; + }; + + map1 { + trip = <&target>; + cooling-device = <&fan 1 2>; + }; + + map2 { + trip = <&cpu_hot>; + cooling-device = <&fan 2 3>; + }; + }; + }; + }; }; &ddc0 { @@ -103,6 +152,11 @@ reset: reset { compatible = "raspberrypi,firmware-reset"; #reset-cells = <1>; }; + + fwpwm: pwm { + compatible = "raspberrypi,firmware-pwm"; + #pwm-cells = <2>; + }; }; &gpio { -- 2.29.1