|  | Nest Labs GPIO Exporter | 
|  | ========================= | 
|  |  | 
|  | This is a psuedo-device that captures the set of GPIOs used by a device | 
|  | that is managed using a userspace driver.  All GPIOs identified within | 
|  | this node will be exported to userspace via sysfs using the names given. | 
|  |  | 
|  | Required Properties: | 
|  | ------------------- | 
|  | - compatible: "nestlabs,gpio-exporter" | 
|  | - reg: This must be zero to ensure a consistent sysfs path | 
|  |  | 
|  | Optional Properties: | 
|  | ------------------- | 
|  | - output-names: a list of strings to be used for the output-gpios. | 
|  | - output-gpios: a list of gpios that will be exported using the matching | 
|  | output-names strings.  They will get their direction set | 
|  | as output. | 
|  | - input-names: a list of strings to be used for the input-gpios. | 
|  | - input-gpios: a list of gpios that will be exported using the matching | 
|  | input-names strings.  They will get their direction set | 
|  | as input. | 
|  |  | 
|  | Example: | 
|  |  | 
|  | em35x-gpios { | 
|  | reg = <0x0 0>; | 
|  | compatible = "nestlabs,gpio-exporter"; | 
|  | output-names = "reset", "wake"; | 
|  | output-gpios = <&gpio2 0 GPIO_ACTIVE_HIGH | 
|  | &gpio2 5 GPIO_ACTIVE_HIGH>; | 
|  | input-names = "irq"; | 
|  | input-gpios = <&gpio2 4 GPIO_ACTIVE_HIGH>; | 
|  | }; |