freebsd-nq/lib/libgpio/libgpio.h
Rui Paulo f12128e4df Import libgpio.
This is a thin wrapper around the kernel interface which should make
it easier to write GPIO applications.  gpioctl(8) will be converted to
use this library in a separate commit.

Differential Revision:	https://reviews.freebsd.org/D1183
Reviewed by:	adrian, loos
Discussed on:	arm@, embedded@
Relnotes:	yes
2014-11-24 21:49:40 +00:00

106 lines
3.3 KiB
C

/*-
* Copyright (c) 2013-2014 Rui Paulo <rpaulo@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _LIBGPIO_H_
#define _LIBGPIO_H_
#include <sys/gpio.h>
__BEGIN_DECLS
#define GPIO_INVALID_HANDLE -1
typedef int gpio_handle_t;
typedef uint32_t gpio_pin_t;
/*
* Structure describing a GPIO pin configuration.
*/
typedef struct {
gpio_pin_t g_pin;
char g_name[GPIOMAXNAME];
uint32_t g_caps;
uint32_t g_flags;
} gpio_config_t;
typedef enum {
GPIO_VALUE_INVALID = -1,
GPIO_VALUE_LOW = GPIO_PIN_LOW,
GPIO_VALUE_HIGH = GPIO_PIN_HIGH
} gpio_value_t;
/*
* Open /dev/gpiocN or a specific device.
*/
gpio_handle_t gpio_open(unsigned int);
gpio_handle_t gpio_open_device(const char *);
void gpio_close(gpio_handle_t);
/*
* Get a list of all the GPIO pins.
*/
int gpio_pin_list(gpio_handle_t, gpio_config_t **);
/*
* GPIO pin configuration.
*
* Retrieve the configuration of a specific GPIO pin. The pin number is
* passed through the gpio_config_t structure.
*/
int gpio_pin_config(gpio_handle_t, gpio_config_t *);
/*
* Sets the GPIO flags on a specific GPIO pin. The pin number and the flags
* to be set are passed through the gpio_config_t structure.
*/
int gpio_pin_set_flags(gpio_handle_t, gpio_config_t *);
/*
* GPIO pin values.
*/
int gpio_pin_get(gpio_handle_t, gpio_pin_t);
int gpio_pin_set(gpio_handle_t, gpio_pin_t, int);
int gpio_pin_toggle(gpio_handle_t, gpio_pin_t);
/*
* Helper functions to set pin states.
*/
int gpio_pin_low(gpio_handle_t, gpio_pin_t);
int gpio_pin_high(gpio_handle_t, gpio_pin_t);
/*
* Helper functions to configure pins.
*/
int gpio_pin_input(gpio_handle_t, gpio_pin_t);
int gpio_pin_output(gpio_handle_t, gpio_pin_t);
int gpio_pin_opendrain(gpio_handle_t, gpio_pin_t);
int gpio_pin_pushpull(gpio_handle_t, gpio_pin_t);
int gpio_pin_tristate(gpio_handle_t, gpio_pin_t);
int gpio_pin_pullup(gpio_handle_t, gpio_pin_t);
int gpio_pin_pulldown(gpio_handle_t, gpio_pin_t);
int gpio_pin_invin(gpio_handle_t, gpio_pin_t);
int gpio_pin_invout(gpio_handle_t, gpio_pin_t);
int gpio_pin_pulsate(gpio_handle_t, gpio_pin_t);
__END_DECLS
#endif /* _LIBGPIO_H_ */