162306a36Sopenharmony_ciBindings for fan connected to GPIO lines
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362306a36Sopenharmony_ciRequired properties:
462306a36Sopenharmony_ci- compatible : "gpio-fan"
562306a36Sopenharmony_ci
662306a36Sopenharmony_ciOptional properties:
762306a36Sopenharmony_ci- gpios: Specifies the pins that map to bits in the control value,
862306a36Sopenharmony_ci  ordered MSB-->LSB.
962306a36Sopenharmony_ci- gpio-fan,speed-map: A mapping of possible fan RPM speeds and the
1062306a36Sopenharmony_ci  control value that should be set to achieve them. This array
1162306a36Sopenharmony_ci  must have the RPM values in ascending order.
1262306a36Sopenharmony_ci- alarm-gpios: This pin going active indicates something is wrong with
1362306a36Sopenharmony_ci  the fan, and a udev event will be fired.
1462306a36Sopenharmony_ci- #cooling-cells: If used as a cooling device, must be <2>
1562306a36Sopenharmony_ci  Also see:
1662306a36Sopenharmony_ci  Documentation/devicetree/bindings/thermal/thermal-cooling-devices.yaml
1762306a36Sopenharmony_ci  min and max states are derived from the speed-map of the fan.
1862306a36Sopenharmony_ci
1962306a36Sopenharmony_ciNote: At least one the "gpios" or "alarm-gpios" properties must be set.
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2162306a36Sopenharmony_ciExamples:
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2362306a36Sopenharmony_ci	gpio_fan {
2462306a36Sopenharmony_ci		compatible = "gpio-fan";
2562306a36Sopenharmony_ci		gpios = <&gpio1 14 1
2662306a36Sopenharmony_ci			 &gpio1 13 1>;
2762306a36Sopenharmony_ci		gpio-fan,speed-map = <0    0
2862306a36Sopenharmony_ci				      3000 1
2962306a36Sopenharmony_ci				      6000 2>;
3062306a36Sopenharmony_ci		alarm-gpios = <&gpio1 15 1>;
3162306a36Sopenharmony_ci	};
3262306a36Sopenharmony_ci	gpio_fan_cool: gpio_fan {
3362306a36Sopenharmony_ci		compatible = "gpio-fan";
3462306a36Sopenharmony_ci		gpios = <&gpio2 14 1
3562306a36Sopenharmony_ci			 &gpio2 13 1>;
3662306a36Sopenharmony_ci		gpio-fan,speed-map =	<0    0>,
3762306a36Sopenharmony_ci					<3000 1>,
3862306a36Sopenharmony_ci					<6000 2>;
3962306a36Sopenharmony_ci		alarm-gpios = <&gpio2 15 1>;
4062306a36Sopenharmony_ci		#cooling-cells = <2>; /* min followed by max */
4162306a36Sopenharmony_ci	};
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