| 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 */ |
| }; |
