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+Bindings for a fan connected to the PWM lines
+
+Required properties:
+- compatible : "pwm-fan"
+- pwms : the PWM that is used to control the PWM fan
+- cooling-levels : PWM duty cycle values in a range from 0 to 255
+ which correspond to thermal cooling states
+
+Optional properties:
+- fan-supply : phandle to the regulator that provides power to the fan
+- interrupts : This contains a single interrupt specifier which
+ describes the tachometer output of the fan as an
+ interrupt source. The output signal must generate a
+ defined number of interrupts per fan revolution, which
+ require that it must be self resetting edge interrupts.
+ See interrupt-controller/interrupts.txt for the format.
+- pulses-per-revolution : define the tachometer pulses per fan revolution as
+ an integer (default is 2 interrupts per revolution).
+ The value must be greater than zero.
+
+Example:
+ fan0: pwm-fan {
+ compatible = "pwm-fan";
+ #cooling-cells = <2>;
+ pwms = <&pwm 0 10000 0>;
+ cooling-levels = <0 102 170 230>;
+ };
+
+ thermal-zones {
+ cpu_thermal: cpu-thermal {
+ thermal-sensors = <&tmu 0>;
+ polling-delay-passive = <0>;
+ polling-delay = <0>;
+ trips {
+ cpu_alert1: cpu-alert1 {
+ temperature = <100000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = "passive";
+ };
+ };
+ cooling-maps {
+ map0 {
+ trip = <&cpu_alert1>;
+ cooling-device = <&fan0 0 1>;
+ };
+ };
+ };
+
+Example 2:
+ fan0: pwm-fan {
+ compatible = "pwm-fan";
+ pwms = <&pwm 0 40000 0>;
+ fan-supply = <&reg_fan>;
+ interrupt-parent = <&gpio5>;
+ interrupts = <1 IRQ_TYPE_EDGE_FALLING>;
+ pulses-per-revolution = <2>;
+ };