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diff --git a/Documentation/devicetree/bindings/hwmon/pwm-fan.txt b/Documentation/devicetree/bindings/hwmon/pwm-fan.txt
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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>;
+	};