pwm.cpp

00001 /***************************************************************************//**
00002  *   @file   pwm.cpp
00003  *   @brief  Implementation of PWM Mbed platform driver interfaces
00004 ********************************************************************************
00005  * Copyright (c) 2021 Analog Devices, Inc.
00006  *
00007  * All rights reserved.
00008  *
00009  * This software is proprietary to Analog Devices, Inc. and its licensors.
00010  * By using this software you agree to the terms of the associated
00011  * Analog Devices Software License Agreement.
00012 *******************************************************************************/
00013 
00014 /******************************************************************************/
00015 /***************************** Include Files **********************************/
00016 /******************************************************************************/
00017 
00018 #include <stdio.h>
00019 #include <mbed.h>
00020 
00021 // Platform drivers needs to be C-compatible to work with other drivers
00022 #ifdef __cplusplus
00023 extern "C"
00024 {
00025 #endif //  _cplusplus
00026 
00027 #include "error.h"
00028 #include "pwm.h"
00029 #include "gpio.h"
00030 #include "pwm_extra.h"
00031 
00032 /******************************************************************************/
00033 /********************** Macros and Constants Definitions **********************/
00034 /******************************************************************************/
00035 
00036 /******************************************************************************/
00037 /********************** Variables and User defined data types *****************/
00038 /******************************************************************************/
00039 
00040 /******************************************************************************/
00041 /************************ Functions Declarations ******************************/
00042 /******************************************************************************/
00043 
00044 /******************************************************************************/
00045 /************************ Functions Definitions *******************************/
00046 /******************************************************************************/
00047 
00048 /**
00049  * @brief   Initialized the PWM interface
00050  * @param   desc[in, out] - Pointer where the configured instance is stored
00051  * @param   param[in] - Configuration information for the instance
00052  * @return  SUCCESS in case of success, FAILURE otherwise.
00053  */
00054 int32_t pwm_init(struct pwm_desc **desc,
00055          const struct pwm_init_param *param)
00056 {
00057     struct pwm_desc *new_pwm_desc;
00058     mbed::PwmOut *pwm;
00059     struct mbed_pwm_desc *new_mbed_pwm_desc;
00060 
00061     if (!desc || !param) {
00062         return FAILURE;
00063     }
00064 
00065     /* Allocate memory for general PWM descriptor */
00066     new_pwm_desc = (pwm_desc *)malloc(sizeof(pwm_desc));
00067     if (!new_pwm_desc) {
00068         goto err_new_pwm_desc;
00069     }
00070 
00071     new_pwm_desc->id = param->id;   // PWM Id
00072     new_pwm_desc->period_ns = param->period_ns; // PWM period
00073 
00074     /* Create and initialize Mbed PWM object */
00075     pwm = new PwmOut((PinName)((mbed_pwm_init_param *)(param->extra))->pwm_pin);
00076     if (!pwm) {
00077         goto err_pwm;
00078     }
00079 
00080     /* Allocate memory for Mbed specific PWM descriptor for future use */
00081     new_mbed_pwm_desc = (mbed_pwm_desc *)malloc(sizeof(mbed_pwm_desc));
00082     if (!new_mbed_pwm_desc) {
00083         goto err_new_mbed_pwm_desc;
00084     }
00085 
00086     new_mbed_pwm_desc->pwm_obj = (mbed::PwmOut *)pwm;
00087     new_pwm_desc->extra = (mbed_pwm_desc *)new_mbed_pwm_desc;
00088 
00089     /* Configure Mbed PWM parameters */
00090     pwm->period_us(param->period_ns / 1000);            // Period in usec
00091     pwm->pulsewidth_us(param->duty_cycle_ns / 1000);    // Duty cycle in usec
00092     pwm_disable(new_pwm_desc);
00093 
00094     *desc = new_pwm_desc;
00095 
00096     return SUCCESS;
00097 
00098 err_new_mbed_pwm_desc:
00099     free(pwm);
00100 err_pwm:
00101     free(new_pwm_desc);
00102 err_new_pwm_desc:
00103     // Nothing to free
00104 
00105     return FAILURE;
00106 }
00107 
00108 
00109 /**
00110  * @brief   Enable the PWM interface
00111  * @param   desc[in, out] - Pointer where the configured instance is stored
00112  * @return  SUCCESS in case of success, FAILURE otherwise.
00113  */
00114 int32_t pwm_enable(struct pwm_desc *desc)
00115 {
00116     mbed::PwmOut *pwm;
00117 
00118     if (desc) {
00119         pwm = (mbed::PwmOut *)(((mbed_pwm_desc *)desc->extra)->pwm_obj);
00120         if (!pwm) {
00121             return FAILURE;
00122         }
00123 
00124         pwm->resume();
00125 
00126         return SUCCESS;
00127     }
00128 
00129     return FAILURE;
00130 }
00131 
00132 
00133 /**
00134  * @brief   Disable the PWM interface
00135  * @param   desc[in, out] - Pointer where the configured instance is stored
00136  * @return  SUCCESS in case of success, FAILURE otherwise.
00137  */
00138 int32_t pwm_disable(struct pwm_desc *desc)
00139 {
00140     mbed::PwmOut *pwm;
00141 
00142     if (desc) {
00143         pwm = (mbed::PwmOut *)(((mbed_pwm_desc *)desc->extra)->pwm_obj);
00144 
00145         if (!pwm) {
00146             return FAILURE;
00147         }
00148 
00149         pwm->suspend();
00150 
00151         return SUCCESS;
00152     }
00153 
00154     return FAILURE;
00155 }
00156 
00157 
00158 /**
00159  * @brief   Remove the memory allocated for PWM device descriptors
00160  * @param   desc[in, out] - Pointer where the configured instance is stored
00161  * @return  SUCCESS in case of success, FAILURE otherwise.
00162  */
00163 int32_t pwm_remove(struct pwm_desc *desc)
00164 {
00165     if (!desc) {
00166         return FAILURE;
00167     }
00168 
00169     if (((mbed_pwm_desc *)desc->extra)->pwm_obj) {
00170         delete((mbed::PwmOut *)((mbed_pwm_desc *)desc->extra)->pwm_obj);
00171     }
00172 
00173     free(desc);
00174 
00175     return SUCCESS;
00176 }
00177 
00178 
00179 #ifdef __cplusplus  // Closing extern c
00180 }
00181 #endif //  _cplusplus