Squashed 'dts/upstream/' content from commit aaba2d45dc2a
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diff --git a/Bindings/hwmon/gpio-fan.txt b/Bindings/hwmon/gpio-fan.txt
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+Bindings for fan connected to GPIO lines
+
+Required properties:
+- compatible : "gpio-fan"
+
+Optional properties:
+- gpios: Specifies the pins that map to bits in the control value,
+ ordered MSB-->LSB.
+- gpio-fan,speed-map: A mapping of possible fan RPM speeds and the
+ control value that should be set to achieve them. This array
+ must have the RPM values in ascending order.
+- alarm-gpios: This pin going active indicates something is wrong with
+ the fan, and a udev event will be fired.
+- #cooling-cells: If used as a cooling device, must be <2>
+ Also see:
+ Documentation/devicetree/bindings/thermal/thermal-cooling-devices.yaml
+ min and max states are derived from the speed-map of the fan.
+
+Note: At least one the "gpios" or "alarm-gpios" properties must be set.
+
+Examples:
+
+ gpio_fan {
+ compatible = "gpio-fan";
+ gpios = <&gpio1 14 1
+ &gpio1 13 1>;
+ gpio-fan,speed-map = <0 0
+ 3000 1
+ 6000 2>;
+ alarm-gpios = <&gpio1 15 1>;
+ };
+ gpio_fan_cool: gpio_fan {
+ compatible = "gpio-fan";
+ gpios = <&gpio2 14 1
+ &gpio2 13 1>;
+ gpio-fan,speed-map = <0 0>,
+ <3000 1>,
+ <6000 2>;
+ alarm-gpios = <&gpio2 15 1>;
+ #cooling-cells = <2>; /* min followed by max */
+ };