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/*
* Author: Thomas Ingleby <thomas.c.ingleby@intel.com>
* Copyright (c) 2014 Intel Corporation.
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
* SPDX-License-Identifier: MIT
*/
#pragma once
/**
* @file
* @brief Pulse Width Modulation module
*
* PWM is the Pulse Width Modulation interface to libmraa. It allows the
* generation of a signal on a pin. Some boards may have higher or lower levels
* of resolution so make sure you check the board & pin you are using before
* hand.
*
* @snippet pwm.c Interesting
*/
#ifdef __cplusplus
extern "C" {
#endif
#include <stdio.h>
#include <fcntl.h>
#include "common.h"
/** Mraa Pwm Context */
typedef struct _pwm* mraa_pwm_context;
/**
* Initialise pwm_context, uses board mapping
*
* @param pin The PWM PIN
* @return pwm context or NULL
*/
mraa_pwm_context mraa_pwm_init(int pin);
/**
* Initialise pwm_context, raw mode
*
* @param chipid The chip inwhich the PWM is under in SYSFS
* @param pin The PWM PIN.
* @return pwm context or NULL
*/
mraa_pwm_context mraa_pwm_init_raw(int chipid, int pin);
/**
* Set the output duty-cycle percentage, as a float
*
* @param dev The Pwm context to use
* @param percentage A floating-point value representing percentage of output.
* The value should lie between 0.0f (representing on 0%) and 1.0f
* Values above or below this range will be set at either 0.0f or 1.0f
* @return Result of operation
*/
mraa_result_t mraa_pwm_write(mraa_pwm_context dev, float percentage);
/**
* Read the output duty-cycle percentage, as a float
*
* @param dev The Pwm context to use
* @return percentage A floating-point value representing percentage of output.
* The value should lie between 0.0f (representing on 0%) and 1.0f
* Values above or below this range will be set at either 0.0f or 1.0f
*/
float mraa_pwm_read(mraa_pwm_context dev);
/**
* Set the PWM period as seconds represented in a float
*
* @param dev The Pwm context to use
* @param seconds Period represented as a float in seconds
* @return Result of operation
*/
mraa_result_t mraa_pwm_period(mraa_pwm_context dev, float seconds);
/**
* Set period, milliseconds.
*
* @param dev The Pwm context to use
* @param ms Milliseconds for period
* @return Result of operation
*/
mraa_result_t mraa_pwm_period_ms(mraa_pwm_context dev, int ms);
/**
* Set period, microseconds
*
* @param dev The Pwm context to use
* @param us Microseconds as period
* @return Result of operation
*/
mraa_result_t mraa_pwm_period_us(mraa_pwm_context dev, int us);
/**
* Set pulsewidth, As represnted by seconds in a (float)
*
* @param dev The Pwm context to use
* @param seconds The duration of a pulse
* @return Result of operation
*/
mraa_result_t mraa_pwm_pulsewidth(mraa_pwm_context dev, float seconds);
/**
* Set pulsewidth, milliseconds
*
* @param dev The Pwm context to use
* @param ms Milliseconds for pulsewidth
* @return Result of operation
*/
mraa_result_t mraa_pwm_pulsewidth_ms(mraa_pwm_context dev, int ms);
/**
* Set pulsewidth, microseconds
*
* @param dev The Pwm context to use
* @param us Microseconds for pulsewidth
* @return Result of operation
*/
mraa_result_t mraa_pwm_pulsewidth_us(mraa_pwm_context dev, int us);
/**
* Set the enable status of the PWM pin. None zero will assume on with output being driven.
* and 0 will disable the output.
*
* @param dev The pwm context to use
* @param enable Toggle status of pin
* @return Result of operation.
*/
mraa_result_t mraa_pwm_enable(mraa_pwm_context dev, int enable);
/**
* Change ownership of context
*
* @param dev the context
* @param owner Ownership boolean
* @return Result of operation
*/
mraa_result_t mraa_pwm_owner(mraa_pwm_context dev, mraa_boolean_t owner);
/**
* Close and unexport the PWM pin
*
* @param dev The pwm context to use
* @return Result of operation
*/
mraa_result_t mraa_pwm_close(mraa_pwm_context dev);
/**
* Get the maximum pwm period in us
*
* @param dev The pwm context to use
* @return max pwm in us
*/
int mraa_pwm_get_max_period(mraa_pwm_context dev);
/**
* Get the minimum pwm period in us
*
* @param dev The pwm context to use
* @return min pwm in us
*/
int mraa_pwm_get_min_period(mraa_pwm_context dev);
#ifdef __cplusplus
}
#endif
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