Add invert setting to GPIO switches

core/config/config.go

@@ -47,8 +47,9 @@ type SwitchRF struct {
 }
 
 type SwitchGPIO struct {
-	Id  string `json:"id"`  // Id used by Smarthome server
-	Pin uint8  `json:"pin"` // The BCM pin to which a GPIO device is attached
+	Id     string `json:"id"`     // Id used by Smarthome server
+	Pin    uint8  `json:"pin"`    // The BCM pin to which a GPIO device is attached
+	Invert bool   `json:"invert"` // Whether the power request should be treated in an inverted manner (mainly useful for relay control)
 }
 
 // A dry-run of the `RadConfigFile()` method used in the healthtest

core/firmware/switch.go

@@ -55,6 +55,14 @@ func SetPower(switchId string, powerOn bool) error {
 		if switchItem.Id == switchId {
 			blocked = false
 			log.Trace(fmt.Sprintf("Successfully handled switch GPIO. (Switch: %s | PowerOn: %t) ", switchId, powerOn))
+			// If the switch uses the `invert` setting, invert the power state
+			if switchItem.Invert {
+				return setPin(
+					switchItem.Pin,
+					!powerOn,
+				)
+			}
+			// Otherwise, use the normal setting
 			return setPin(
 				switchItem.Pin,
 				powerOn,