uapi

const (

	// LineChangedRequested indicates the line has been requested.
	LineChangedRequested ChangeType

	// LineChangedReleased indicates the line has been released.
	LineChangedReleased

	// LineChangedConfig indicates the line configuration has changed.
	LineChangedConfig
)

const (
	// EventRequestRisingEdge requests rising edge events.
	// This means a transition from a low logical state to a high logical state.
	// For active high lines (the default) this means a transition from a
	// physical low to a physical high.
	// Note that for active low lines this means a transition from a physical
	// high to a physical low.
	EventRequestRisingEdge EventFlag = 1 << iota

	// EventRequestFallingEdge requests falling edge events.
	// This means a transition from a high logical state to a low logical state.
	// For active high lines (the default) this means a transition from a
	// physical high to a physical low.
	// Note that for active low lines this means a transition from a physical
	// low to a physical high.
	EventRequestFallingEdge

	// EventRequestBothEdges requests both rising and falling edge events.
	// This is equivalent to requesting both EventRequestRisingEdge and
	// EventRequestRisingEdge.
	EventRequestBothEdges = EventRequestRisingEdge | EventRequestFallingEdge
)

const (
	// HandleRequestInput requests the line as an input.
	//
	// This is ignored if Output is also set.
	HandleRequestInput HandleFlag = 1 << iota

	// HandleRequestOutput requests the line as an output.
	//
	// This takes precedence over Input, if both are set.
	HandleRequestOutput

	// HandleRequestActiveLow requests the line be made active low.
	HandleRequestActiveLow

	// HandleRequestOpenDrain requests the line be made open drain.
	//
	// This option requires the line to be requested as an Output.
	// This cannot be set at the same time as OpenSource.
	HandleRequestOpenDrain

	// HandleRequestOpenSource requests the line be made open source.
	//
	// This option requires the line to be requested as an Output.
	// This cannot be set at the same time as OpenDrain.
	HandleRequestOpenSource

	// HandleRequestPullUp requests the line have pull-up enabled.
	HandleRequestPullUp

	// HandleRequestPullDown requests the line have pull-down enabled.
	HandleRequestPullDown

	// HandleRequestBiasDisable requests the line have bias disabled.
	HandleRequestBiasDisable

	// HandlesMax is the maximum number of lines that can be requested in a
	// single request.
	HandlesMax = 64
)

const (
	// LineAttributeIDFlags indicates the attribute contains LineFlagV2 flags.
	LineAttributeIDFlags LineAttributeID = iota + 1

	// LineAttributeIDOutputValues indicates the attribute contains line output values.
	LineAttributeIDOutputValues

	// LineAttributeIDDebounce indicates the attribute contains a debounce period.
	LineAttributeIDDebounce
)

const (
	// LineEventRisingEdge indicates the event is a rising edge.
	LineEventRisingEdge LineEventID = iota + 1

	// LineEventFallingEdge indicates the event is a falling edge.
	LineEventFallingEdge
)

const (
	// LineFlagUsed indicates that the line has been requested.
	// It may have been requested by this process or another process.
	// The line cannot be requested again until this flag is clear.
	LineFlagUsed LineFlag = 1 << iota

	// LineFlagIsOut indicates that the line is an output.
	LineFlagIsOut

	// LineFlagActiveLow indicates that the line is active low.
	LineFlagActiveLow

	// LineFlagOpenDrain indicates that the line will pull low when set low but
	// float when set high. This flag only applies to output lines.
	// An output cannot be both open drain and open source.
	LineFlagOpenDrain

	// LineFlagOpenSource indicates that the line will pull high when set high
	// but float when set low. This flag only applies to output lines.
	// An output cannot be both open drain and open source.
	LineFlagOpenSource

	// LineFlagPullUp indicates that the internal line pull up is enabled.
	LineFlagPullUp

	// LineFlagPullDown indicates that the internal line pull down is enabled.
	LineFlagPullDown

	// LineFlagBiasDisabled indicates that the internal line bias is disabled.
	LineFlagBiasDisabled
)

const (
	// LineFlagV2Used indicates that the line is already in use.
	// It may have been requested by this process or another process,
	// or may be reserved by the kernel.
	//
	// The line cannot be requested until this flag is clear.
	LineFlagV2Used LineFlagV2 = 1 << iota

	// LineFlagV2ActiveLow indicates that the line is active low.
	LineFlagV2ActiveLow

	// LineFlagV2Input indicates that the line direction is an input.
	LineFlagV2Input

	// LineFlagV2Output indicates that the line direction is an output.
	LineFlagV2Output

	// LineFlagV2EdgeRising indicates that edge detection is enabled for rising
	// edges.
	LineFlagV2EdgeRising

	// LineFlagV2EdgeFalling indicates that edge detection is enabled for
	// falling edges.
	LineFlagV2EdgeFalling

	// LineFlagV2OpenDrain indicates that the line drive is open drain.
	LineFlagV2OpenDrain

	// LineFlagV2OpenSource indicates that the line drive is open source.
	LineFlagV2OpenSource

	// LineFlagV2BiasPullUp indicates that the line bias is pull-up.
	LineFlagV2BiasPullUp

	// LineFlagV2BiasPullDown indicates that the line bias is set pull-down.
	LineFlagV2BiasPullDown

	// LineFlagV2BiasDisabled indicates that the line bias is disabled.
	LineFlagV2BiasDisabled

	// LineFlagV2EventClockRealtime indicates that the CLOCK_REALTIME will be
	// the source for event timestamps.
	LineFlagV2EventClockRealtime

	// LineFlagV2DirectionMask is a mask for all direction flags.
	LineFlagV2DirectionMask = LineFlagV2Input | LineFlagV2Output

	// LineFlagV2EdgeMask is a mask for all edge flags.
	LineFlagV2EdgeMask = LineFlagV2EdgeRising | LineFlagV2EdgeFalling

	// LineFlagV2EdgeBoth is a helper value for selecting edge detection on
	// both edges.
	LineFlagV2EdgeBoth = LineFlagV2EdgeMask

	// LineFlagV2DriveMask is a mask for all drive flags.
	LineFlagV2DriveMask = LineFlagV2OpenDrain | LineFlagV2OpenSource

	// LineFlagV2BiasMask is a mask for all bias flags.
	LineFlagV2BiasMask = LineFlagV2BiasDisabled | LineFlagV2BiasPullUp | LineFlagV2BiasPullDown
)