le_gpio_interface.h File Reference

#include "legato.h"

Go to the source code of this file.

Typedefs
typedef struct le_gpio_ChangeEventHandler *	le_gpio_ChangeEventHandlerRef_t
typedef void(*	le_gpio_ChangeCallbackFunc_t) (bool state, void *contextPtr)

Enumerations
enum	le_gpio_Polarity_t { LE_GPIO_ACTIVE_HIGH, LE_GPIO_ACTIVE_LOW }
enum	le_gpio_Edge_t { LE_GPIO_EDGE_NONE, LE_GPIO_EDGE_RISING, LE_GPIO_EDGE_FALLING, LE_GPIO_EDGE_BOTH }
enum	le_gpio_PullUpDown_t { LE_GPIO_PULL_OFF, LE_GPIO_PULL_DOWN, LE_GPIO_PULL_UP }

Functions
void	le_gpio_ConnectService (void)
void	le_gpio_DisconnectService (void)
le_result_t	le_gpio_SetInput (le_gpio_Polarity_t polarity)
le_result_t	le_gpio_SetPushPullOutput (le_gpio_Polarity_t polarity, bool value)
le_result_t	le_gpio_SetTriStateOutput (le_gpio_Polarity_t polarity)
le_result_t	le_gpio_SetOpenDrainOutput (le_gpio_Polarity_t polarity, bool value)
le_result_t	le_gpio_EnablePullUp (void)
le_result_t	le_gpio_EnablePullDown (void)
le_result_t	le_gpio_DisableResistors (void)
le_result_t	le_gpio_Activate (void)
le_result_t	le_gpio_Deactivate (void)
le_result_t	le_gpio_SetHighZ (void)
bool	le_gpio_Read (void)
le_gpio_ChangeEventHandlerRef_t	le_gpio_AddChangeEventHandler (le_gpio_Edge_t trigger, le_gpio_ChangeCallbackFunc_t handlerPtr, void *contextPtr, int32_t sampleMs)
void	le_gpio_RemoveChangeEventHandler (le_gpio_ChangeEventHandlerRef_t addHandlerRef)
le_result_t	le_gpio_SetEdgeSense (le_gpio_Edge_t trigger)
le_result_t	le_gpio_DisableEdgeSense (void)
bool	le_gpio_IsOutput (void)
bool	le_gpio_IsInput (void)
le_gpio_Edge_t	le_gpio_GetEdgeSense (void)
le_gpio_Polarity_t	le_gpio_GetPolarity (void)
bool	le_gpio_IsActive (void)
le_gpio_PullUpDown_t	le_gpio_GetPullUpDown (void)

Detailed Description

Legato GPIO include file.

Copyright (C) Sierra Wireless Inc. Use of this work is subject to license.

Typedef Documentation

typedef void(* le_gpio_ChangeCallbackFunc_t) (bool state, void *contextPtr)

State change event handler (callback).

Parameters

state	New state of pin (true = active, false = inactive).
contextPtr

typedef struct le_gpio_ChangeEventHandler* le_gpio_ChangeEventHandlerRef_t

Reference type used by Add/Remove functions for EVENT 'le_gpio_ChangeEvent'

Enumeration Type Documentation

enum le_gpio_Edge_t

Edge transitions.

Enumerator
LE_GPIO_EDGE_NONE	No edge detection.
LE_GPIO_EDGE_RISING	Notify when voltage goes from low to high.
LE_GPIO_EDGE_FALLING	Notify when voltage goes from high to low.
LE_GPIO_EDGE_BOTH	Notify when pin voltage changes state in either direction.

enum le_gpio_Polarity_t

Pin polarities.

Enumerator
LE_GPIO_ACTIVE_HIGH	GPIO active-high, output is 1.
LE_GPIO_ACTIVE_LOW	GPIO active-low, output is 0.

enum le_gpio_PullUpDown_t

Pull up or down.

Enumerator
LE_GPIO_PULL_OFF	Neither resistor is enabled.
LE_GPIO_PULL_DOWN	Pulldown resistor is enabled.
LE_GPIO_PULL_UP	Pullup resistor is enabled.

Function Documentation

le_result_t le_gpio_Activate

(

void

)

Set output pin to active state.

Warning

Only valid for output pins.

le_gpio_ChangeEventHandlerRef_t le_gpio_AddChangeEventHandler	(	le_gpio_Edge_t	trigger,
		le_gpio_ChangeCallbackFunc_t	handlerPtr,
		void *	contextPtr,
		int32_t	sampleMs
	)

Add handler function for EVENT 'le_gpio_ChangeEvent'

Register a callback function to be called when an input pin changes state.

If the pin is not capable of interrupt-driven operation, then it will be sampled every sampleMs milliseconds. Otherwise, sampleMs will be ignored.

If this fails, either because the handler cannot be registered, or setting the edge detection fails, then it will return a NULL reference.

Parameters

[in]	trigger	Change(s) that should trigger the callback to be called.
[in]	handlerPtr
[in]	contextPtr
[in]	sampleMs	If not interrupt capable, sample the input this often (ms).

void le_gpio_ConnectService

(

void

)

Connect the current client thread to the service providing this API.

This function must be called before any other functions in this API. Normally, it's automatically called for the main thread, but must be explicitly called for other threads. For details, see Client-specific Functions.

This function is created automatically.

le_result_t le_gpio_Deactivate

(

void

)

Set output pin to inactive state.

Warning

Only valid for output pins.

le_result_t le_gpio_DisableEdgeSense

(

void

)

Turn off edge detection

le_result_t le_gpio_DisableResistors

(

void

)

Disable the pull-up and pull-down resistors. Does nothing if both are already disabled.

void le_gpio_DisconnectService

(

void

)

Disconnect the current client thread from the service providing this API.

Normally, this function doesn't need to be called. After this function is called, there's no longer a connection to the service, and the functions in this API can't be used. For details, see Client-specific Functions.

This function is created automatically.

le_result_t le_gpio_EnablePullDown

(

void

)

Enable the pull-down resistor (disables pull-up if previously enabled).

le_result_t le_gpio_EnablePullUp

(

void

)

Enable the pull-up resistor (disables pull-down if previously enabled).

le_gpio_Edge_t le_gpio_GetEdgeSense

(

void

)

Get the current value of edge sensing.

Returns

The current configured value

Note

it is invalid to read the edge sense of an output

le_gpio_Polarity_t le_gpio_GetPolarity

(

void

)

Get the current value the pin polarity.

Returns

The current configured value

le_gpio_PullUpDown_t le_gpio_GetPullUpDown

(

void

)

Get the current value of pull up and down resistors.

Returns

The current configured value

bool le_gpio_IsActive

(

void

)

Check if the pin is currently active.

Returns

true = active, false = inactive.

Note

this function can only be used on output pins

bool le_gpio_IsInput

(

void

)

Check if the pin is configured as an input.

Returns

true = input, false = output.

bool le_gpio_IsOutput

(

void

)

Check if the pin is configured as an output.

Returns

true = output, false = input.

bool le_gpio_Read

(

void

)

Read value of GPIO input pin.

Returns

true = active, false = inactive.

Note

It is invalid to read an output pin.

void le_gpio_RemoveChangeEventHandler

(

le_gpio_ChangeEventHandlerRef_t

addHandlerRef

)

Remove handler function for EVENT 'le_gpio_ChangeEvent'

Parameters

[in]

addHandlerRef

le_result_t le_gpio_SetEdgeSense

(

le_gpio_Edge_t

trigger

)

Set the edge detection mode. This function can only be used when a handler is registered in order to prevent interrupts being generated and not handled

Parameters

[in]

trigger

Change(s) that should trigger the callback to be called.

le_result_t le_gpio_SetHighZ

(

void

)

Set output pin to high impedance state.

Warning

Only valid for tri-state or open-drain output pins.

le_result_t le_gpio_SetInput

(

le_gpio_Polarity_t

polarity

)

Configure the pin as an input pin.

Parameters

[in]

polarity

Active-high or active-low.

le_result_t le_gpio_SetOpenDrainOutput	(	le_gpio_Polarity_t	polarity,
		bool	value
	)

Configure the pin as an open-drain output pin. "High" is a high-impedance state, while "Low" pulls the pin to ground.

Parameters

[in]	polarity	Active-high or active-low.
[in]	value	Initial value to drive (true = active, false = inactive)

le_result_t le_gpio_SetPushPullOutput	(	le_gpio_Polarity_t	polarity,
		bool	value
	)

Configure the pin as a push-pull output pin.

Parameters

[in]	polarity	Active-high or active-low.
[in]	value	Initial value to drive (true = active, false = inactive)

le_result_t le_gpio_SetTriStateOutput

(

le_gpio_Polarity_t

polarity

)

Configure the pin as a tri-state output pin.

Note

The initial state will be high-impedance.

Parameters

[in]

polarity

Active-high or active-low.