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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 an interrupt specifier for each fan
+ tachometer output connected to 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 number of pulses per fan revolution for
+ each tachometer input 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>;
+ };
+
+Example 3:
+ fan0: pwm-fan {
+ compatible = "pwm-fan";
+ pwms = <&pwm1 0 25000 0>;
+ interrupts-extended = <&gpio1 1 IRQ_TYPE_EDGE_FALLING>,
+ <&gpio2 5 IRQ_TYPE_EDGE_FALLING>;
+ pulses-per-revolution = <2>, <1>;
+ };