zephyr/include/dt-bindings/gpio/gpio.h

84 lines
2.1 KiB
C

/*
* Copyright (c) 2019 Piotr Mienkowski
* Copyright (c) 2018 Linaro Limited
*
* SPDX-License-Identifier: Apache-2.0
*/
#ifndef ZEPHYR_INCLUDE_DT_BINDINGS_GPIO_GPIO_H_
#define ZEPHYR_INCLUDE_DT_BINDINGS_GPIO_GPIO_H_
/**
* @brief GPIO Driver APIs
* @defgroup gpio_interface GPIO Driver APIs
* @ingroup io_interfaces
* @{
*/
/**
* @name GPIO pin active level flags
* @{
*/
/** GPIO pin is active (has logical value '1') in low state. */
#define GPIO_ACTIVE_LOW (1 << 0)
/** GPIO pin is active (has logical value '1') in high state. */
#define GPIO_ACTIVE_HIGH (0 << 0)
/** @} */
/**
* @name GPIO pin drive flags
* @{
*/
/** @cond INTERNAL_HIDDEN */
/* Configures GPIO output in single-ended mode (open drain or open source). */
#define GPIO_SINGLE_ENDED (1 << 1)
/* Configures GPIO output in push-pull mode */
#define GPIO_PUSH_PULL (0 << 1)
/* Indicates single ended open drain mode (wired AND). */
#define GPIO_LINE_OPEN_DRAIN (1 << 2)
/* Indicates single ended open source mode (wired OR). */
#define GPIO_LINE_OPEN_SOURCE (0 << 2)
/** @endcond */
/** Configures GPIO output in open drain mode (wired AND).
*
* @note 'Open Drain' mode also known as 'Open Collector' is an output
* configuration which behaves like a switch that is either connected to ground
* or disconnected.
*/
#define GPIO_OPEN_DRAIN (GPIO_SINGLE_ENDED | GPIO_LINE_OPEN_DRAIN)
/** Configures GPIO output in open source mode (wired OR).
*
* @note 'Open Source' is a term used by software engineers to describe output
* mode opposite to 'Open Drain'. It behaves like a switch that is either
* connected to power supply or disconnected. There exist no corresponding
* hardware schematic and the term is generally unknown to hardware engineers.
*/
#define GPIO_OPEN_SOURCE (GPIO_SINGLE_ENDED | GPIO_LINE_OPEN_SOURCE)
/** @} */
/**
* @name GPIO pin bias flags
* @{
*/
/** Enables GPIO pin pull-up. */
#define GPIO_PULL_UP (1 << 4)
/** Enable GPIO pin pull-down. */
#define GPIO_PULL_DOWN (1 << 5)
/** @} */
/**
* @}
*/
#endif /* ZEPHYR_INCLUDE_DT_BINDINGS_GPIO_GPIO_H_ */