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/*
* Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 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.
*
* Neither the name of ARM nor the names of its contributors may be used
* to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT HOLDER OR CONTRIBUTORS 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.
*
* GPIO -- General Purpose Input/Output
*
* Defines a simple and generic interface to access GPIO device.
*
*/
#include <assert.h>
#include <errno.h>
#include <gpio.h>
/*
* The gpio implementation
*/
static const gpio_ops_t *ops;
int gpio_get_direction(int gpio)
{
assert(ops);
assert(ops->get_direction != 0);
assert(gpio >= 0);
return ops->get_direction(gpio);
}
void gpio_set_direction(int gpio, int direction)
{
assert(ops);
assert(ops->set_direction != 0);
assert((direction == GPIO_DIR_OUT) || (direction == GPIO_DIR_IN));
assert(gpio >= 0);
ops->set_direction(gpio, direction);
}
int gpio_get_value(int gpio)
{
assert(ops);
assert(ops->get_value != 0);
assert(gpio >= 0);
return ops->get_value(gpio);
}
void gpio_set_value(int gpio, int value)
{
assert(ops);
assert(ops->set_value != 0);
assert((value == GPIO_LEVEL_LOW) || (value == GPIO_LEVEL_HIGH));
assert(gpio >= 0);
ops->set_value(gpio, value);
}
void gpio_set_pull(int gpio, int pull)
{
assert(ops);
assert(ops->set_pull != 0);
assert((pull == GPIO_PULL_NONE) || (pull == GPIO_PULL_UP) ||
(pull == GPIO_PULL_DOWN));
assert(gpio >= 0);
ops->set_pull(gpio, pull);
}
int gpio_get_pull(int gpio)
{
assert(ops);
assert(ops->get_pull != 0);
assert(gpio >= 0);
return ops->get_pull(gpio);
}
/*
* Initialize the gpio. The fields in the provided gpio
* ops pointer must be valid.
*/
void gpio_init(const gpio_ops_t *ops_ptr)
{
assert(ops_ptr != 0 &&
(ops_ptr->get_direction != 0) &&
(ops_ptr->set_direction != 0) &&
(ops_ptr->get_value != 0) &&
(ops_ptr->set_value != 0));
ops = ops_ptr;
}