GPIO HAL functions

Modules
	GPIO HAL tests
	The GPIO HAL tests ensure driver conformance to defined behaviour.

Data Structures
struct	gpio_capabilities_t
	GPIO capabilities for a given pin. More...

Functions
uint32_t	gpio_set (PinName pin)
	Set the given pin as GPIO. More...
int	gpio_is_connected (const gpio_t *obj)
	Checks if gpio object is connected (pin was not initialized with NC) More...
void	gpio_init (gpio_t *obj, PinName pin)
	Initialize the GPIO pin. More...
void	gpio_free (gpio_t *obj)
	Releases the GPIO pin. More...
void	gpio_mode (gpio_t *obj, PinMode mode)
	Set the input pin mode. More...
void	gpio_dir (gpio_t *obj, PinDirection direction)
	Set the pin direction. More...
void	gpio_write (gpio_t *obj, int value)
	Set the output value. More...
int	gpio_read (gpio_t *obj)
	Read the input value. More...
void	gpio_init_in (gpio_t *gpio, PinName pin)
	Init the input pin and set mode to PullDefault. More...
void	gpio_init_in_ex (gpio_t *gpio, PinName pin, PinMode mode)
	Init the input pin and set the mode. More...
void	gpio_init_out (gpio_t *gpio, PinName pin)
	Init the output pin as an output, with predefined output value 0. More...
void	gpio_init_out_ex (gpio_t *gpio, PinName pin, int value)
	Init the pin as an output and set the output value. More...
void	gpio_init_inout (gpio_t *gpio, PinName pin, PinDirection direction, PinMode mode, int value)
	Init the pin to be in/out. More...
void	gpio_get_capabilities (gpio_t *gpio, gpio_capabilities_t *cap)
	Fill the given gpio_capabilities_t instance according to pin capabilities. More...
const PinMap *	gpio_pinmap (void)
	Get the pins that support all GPIO tests. More...

Detailed Description

Defined behavior

• gpio_init and other init functions can be called with NC or a valid PinName for the target - Verified by gpio_nc_test
• gpio_is_connected can be used to test whether a gpio_t object was initialized with NC - Verified by gpio_nc_test
• gpio_init initializes the GPIO pin
• gpio_free returns the pin owned by the GPIO object to its reset state
• gpio_mode sets the mode of the given pin
• gpio_dir sets the direction of the given pin
• gpio_write sets the gpio output value
• gpio_read reads the input value
• gpio_init_in inits the input pin and sets mode to PullDefault
• gpio_init_in_ex inits the input pin and sets the mode
• gpio_init_out inits the pin as an output, with predefined output value 0
• gpio_init_out_ex inits the pin as an output and sets the output value
• gpio_init_inout inits the pin to be input/output and set pin mode and value
• The GPIO operations gpio_write, gpio_read take less than 20us to complete
• The function gpio_get_capabilities fills the given gpio_capabilities_t instance according to pin capabilities.

Undefined behavior

• Calling any gpio_mode, gpio_dir, gpio_write or gpio_read on a gpio_t object that was initialized with NC.
• Calling gpio_set with NC.

Function Documentation

gpio_set()

uint32_t gpio_set

(

PinName

pin

)

Set the given pin as GPIO.

Parameters

pin	The pin to be set as GPIO

Returns

The GPIO port mask for this pin

gpio_is_connected()

int gpio_is_connected

(

const gpio_t *

obj

)

Checks if gpio object is connected (pin was not initialized with NC)

Parameters

obj	The GPIO object

Returns

0 if object was initialized with NC

non-zero if object was initialized with a valid PinName

gpio_init()

void gpio_init	(	gpio_t *	obj,
		PinName	pin
	)

Initialize the GPIO pin.

Parameters

obj	The GPIO object to initialize
pin	The GPIO pin to initialize (may be NC)

gpio_free()

void gpio_free

(

gpio_t *

obj

)

Releases the GPIO pin.

Parameters

obj	The GPIO object to release

gpio_mode()

void gpio_mode	(	gpio_t *	obj,
		PinMode	mode
	)

Set the input pin mode.

Parameters

obj	The GPIO object (must be connected)
mode	The pin mode to be set

gpio_dir()

void gpio_dir	(	gpio_t *	obj,
		PinDirection	direction
	)

Set the pin direction.

Parameters

obj	The GPIO object (must be connected)
direction	The pin direction to be set

gpio_write()

void gpio_write	(	gpio_t *	obj,
		int	value
	)

Set the output value.

Parameters

obj	The GPIO object (must be connected)
value	The value to be set

gpio_read()

int gpio_read

(

gpio_t *

obj

)

Read the input value.

Parameters

obj	The GPIO object (must be connected)

Returns

An integer value 1 or 0

gpio_init_in()

void gpio_init_in	(	gpio_t *	gpio,
		PinName	pin
	)

Init the input pin and set mode to PullDefault.

Parameters

gpio	The GPIO object
pin	The pin name (may be NC)

gpio_init_in_ex()

void gpio_init_in_ex	(	gpio_t *	gpio,
		PinName	pin,
		PinMode	mode
	)

Init the input pin and set the mode.

Parameters

gpio	The GPIO object
pin	The pin name (may be NC)
mode	The pin mode to be set

gpio_init_out()

void gpio_init_out	(	gpio_t *	gpio,
		PinName	pin
	)

Init the output pin as an output, with predefined output value 0.

Parameters

gpio	The GPIO object
pin	The pin name (may be NC)

gpio_init_out_ex()

void gpio_init_out_ex	(	gpio_t *	gpio,
		PinName	pin,
		int	value
	)

Init the pin as an output and set the output value.

Parameters

gpio	The GPIO object
pin	The pin name (may be NC)
value	The value to be set

gpio_init_inout()

void gpio_init_inout	(	gpio_t *	gpio,
		PinName	pin,
		PinDirection	direction,
		PinMode	mode,
		int	value
	)

Init the pin to be in/out.

Parameters

gpio	The GPIO object
pin	The pin name (may be NC)
direction	The pin direction to be set
mode	The pin mode to be set
value	The value to be set for an output pin

gpio_get_capabilities()

void gpio_get_capabilities	(	gpio_t *	gpio,
		gpio_capabilities_t *	cap
	)

Fill the given gpio_capabilities_t instance according to pin capabilities.

gpio_pinmap()

const PinMap * gpio_pinmap

(

void

)

Get the pins that support all GPIO tests.

Return a PinMap array of pins that support GPIO. The array is terminated with {NC, NC, 0}.

Targets should override the weak implementation of this function to provide the actual pinmap for GPIO testing.

Returns

PinMap array