diff options
author | Haojian Zhuang <haojian.zhuang@linaro.org> | 2016-01-27 13:18:21 +0800 |
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committer | Haojian Zhuang <haojian.zhuang@linaro.org> | 2016-02-12 23:19:12 +0800 |
commit | 1ffecc24000c5ce3241a7b205d9bd5bced7fae58 (patch) | |
tree | 1cb7616773a66cc01e9d33d7d52f7afe250b5fac /drivers/gpio | |
parent | 870d881ced126bd492fe96f6a7bedd0d869dd23a (diff) |
gpio: add gpio framework
Define the gpio ops in gpio driver.
Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>
Diffstat (limited to 'drivers/gpio')
-rw-r--r-- | drivers/gpio/gpio.c | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/drivers/gpio/gpio.c b/drivers/gpio/gpio.c new file mode 100644 index 00000000..c06172fc --- /dev/null +++ b/drivers/gpio/gpio.c @@ -0,0 +1,96 @@ +/* + * 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); +} + +/* + * 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; +} |