gpio.cpp

00001 /***************************************************************************//**
00002  *   @file   gpio.cpp
00003  *   @brief  Implementation of GPIO Mbed platform driver interfaces
00004 ********************************************************************************
00005  * Copyright (c) 2019 - 2021 Analog Devices, Inc.
00006  * All rights reserved.
00007  *
00008  * This software is proprietary to Analog Devices, Inc. and its licensors.
00009  * By using this software you agree to the terms of the associated
00010  * Analog Devices Software License Agreement.
00011 *******************************************************************************/
00012 
00013 /******************************************************************************/
00014 /************************ Includes Files *******************************/
00015 /******************************************************************************/
00016 #include <stdio.h>
00017 #include <stdlib.h>
00018 #include <mbed.h>
00019 
00020 // Platform drivers needs to be C-compatible to work with other drivers
00021 #ifdef __cplusplus
00022 extern "C"
00023 {
00024 #endif //  _cplusplus
00025 
00026 #include "error.h"
00027 #include "gpio.h"
00028 #include "gpio_extra.h"
00029 
00030 /******************************************************************************/
00031 /************************ Functions Definitions *******************************/
00032 /******************************************************************************/
00033 
00034 /**
00035  * @brief Obtain the GPIO decriptor.
00036  * @param desc - The GPIO descriptor.
00037  * @param gpio_number - The number of the GPIO.
00038  * @return SUCCESS in case of success, FAILURE otherwise.
00039  */
00040 int32_t gpio_get(struct gpio_desc **desc, const struct gpio_init_param *param)
00041 {
00042     gpio_desc *new_gpio;
00043 
00044     if (desc && param) {
00045         // Create the gpio description object for the device
00046         new_gpio = (gpio_desc *)calloc(1, sizeof(gpio_desc)) ;
00047         if (!new_gpio) {
00048             goto err_new_gpio;
00049         }
00050 
00051         new_gpio->number = param->number;
00052 
00053         // Create the gpio extra descriptor object to store extra mbed gpio info
00054         mbed_gpio_desc *gpio_desc_extra = (mbed_gpio_desc *)calloc(1,
00055                           sizeof(mbed_gpio_desc));
00056         if (!gpio_desc_extra) {
00057             goto err_gpio_desc_extra;
00058         }
00059 
00060         gpio_desc_extra->direction = GPIO_IN;
00061         gpio_desc_extra->gpio_pin = NULL;
00062 
00063         if (param->extra) {
00064             gpio_desc_extra->pin_mode = ((mbed_gpio_init_param *)param->extra)->pin_mode;
00065         } else {
00066             gpio_desc_extra->pin_mode = NULL;
00067         }
00068 
00069         new_gpio->extra = gpio_desc_extra;
00070         *desc = new_gpio;
00071 
00072         return SUCCESS;
00073     }
00074 
00075 err_gpio_desc_extra:
00076     free(new_gpio);
00077 err_new_gpio:
00078     // Nothing to free
00079 
00080     return FAILURE;
00081 }
00082 
00083 
00084 /**
00085  * @brief Get the value of an optional GPIO.
00086  * @param desc - The GPIO descriptor.
00087  * @param param - GPIO Initialization parameters.
00088  * @return SUCCESS in case of success, FAILURE otherwise.
00089  */
00090 int32_t gpio_get_optional(struct gpio_desc **desc,
00091               const struct gpio_init_param *param)
00092 {
00093     if (param) {
00094         return gpio_get(desc, param);
00095     } else {
00096         *desc = NULL;
00097         return SUCCESS;
00098     }
00099 }
00100 
00101 
00102 /**
00103  * @brief Free the resources allocated by gpio_get().
00104  * @param desc - The GPIO descriptor.
00105  * @return SUCCESS in case of success, FAILURE otherwise.
00106  */
00107 int32_t gpio_remove(struct gpio_desc *desc)
00108 {
00109     if (desc) {
00110         // Free the gpio object
00111         if(((mbed_gpio_desc *)(desc->extra))->gpio_pin) {
00112             free(((mbed_gpio_desc *)(desc->extra))->gpio_pin);
00113         }
00114 
00115         // Free the gpio extra descriptor object
00116         if((mbed_gpio_desc *)(desc->extra)) {
00117             free((mbed_gpio_desc *)(desc->extra));
00118         }
00119 
00120         // Free the gpio descriptor object
00121         free(desc);
00122 
00123         return SUCCESS;
00124     }
00125 
00126     return FAILURE;
00127 }
00128 
00129 
00130 /**
00131  * @brief Enable the input direction of the specified GPIO.
00132  * @param desc - The GPIO descriptor.
00133  * @return SUCCESS in case of success, FAILURE otherwise.
00134  * @note does not support reconfiguration of already set pin direction
00135  */
00136 int32_t gpio_direction_input(struct gpio_desc *desc)
00137 {
00138     DigitalIn *gpio_input;      // pointer to gpio input object
00139     mbed_gpio_desc *gpio_desc_extra;   // pointer to gpio desc extra parameters
00140 
00141     if (desc && desc->extra) {
00142         gpio_desc_extra = (mbed_gpio_desc *)(desc->extra);
00143         if (gpio_desc_extra->gpio_pin == NULL) {
00144             // Configure and instantiate GPIO pin as input
00145             gpio_input = new DigitalIn((PinName)desc->number);
00146             if (!gpio_input) {
00147                 goto err_gpio_input;
00148             }
00149 
00150             gpio_desc_extra->gpio_pin = (mbed_gpio_desc *)gpio_input;
00151             gpio_desc_extra->direction = GPIO_IN;
00152 
00153             // Set the gpio pin mode
00154             gpio_input->mode((PinMode)((mbed_gpio_desc *)desc->extra)->pin_mode);
00155 
00156             return SUCCESS;
00157         }
00158     }
00159 
00160 err_gpio_input:
00161     // Nothing to free
00162 
00163     return FAILURE;
00164 }
00165 
00166 
00167 /**
00168  * @brief Enable the output direction of the specified GPIO.
00169  * @param desc - The GPIO descriptor.
00170  * @param value - The value.
00171  *                Example: GPIO_HIGH
00172  *                         GPIO_LOW
00173  * @return SUCCESS in case of success, FAILURE otherwise.
00174  * @note does not support reconfiguration of already set pin direction
00175  */
00176 int32_t gpio_direction_output(struct gpio_desc *desc, uint8_t value)
00177 {
00178     DigitalOut *gpio_output;        // pointer to gpio output object
00179     mbed_gpio_desc *gpio_desc_extra;   // pointer to gpio desc extra parameters
00180 
00181     if(desc && desc->extra) {
00182         gpio_desc_extra = (mbed_gpio_desc *)(desc->extra);
00183         if (gpio_desc_extra->gpio_pin == NULL) {
00184 
00185             // Configure and instantiate GPIO pin as output
00186             gpio_output = new DigitalOut((PinName)desc->number);
00187 
00188             if (!gpio_output) {
00189                 goto err_gpio_output;
00190             }
00191 
00192             gpio_desc_extra->gpio_pin = (mbed_gpio_desc *)gpio_output;
00193             gpio_desc_extra->direction = GPIO_OUT;
00194 
00195             // Set the GPIO value
00196             if(gpio_set_value(desc, value) == SUCCESS) {
00197                 return SUCCESS;
00198             }
00199         }
00200     }
00201 
00202 err_gpio_output:
00203     // Nothing to free
00204 
00205     return FAILURE;
00206 }
00207 
00208 
00209 /**
00210  * @brief Get the direction of the specified GPIO.
00211  * @param desc - The GPIO descriptor.
00212  * @param direction - The direction.
00213  *                    Example: GPIO_OUT
00214  *                             GPIO_IN
00215  * @return SUCCESS in case of success, FAILURE otherwise.
00216  */
00217 int32_t gpio_get_direction(struct gpio_desc *desc, uint8_t *direction)
00218 {
00219     mbed_gpio_desc *gpio_desc_extra;     // pointer to gpio desc extra parameters
00220 
00221     if(desc && desc->extra) {
00222         gpio_desc_extra = (mbed_gpio_desc *)(desc->extra);
00223 
00224         if (gpio_desc_extra->gpio_pin) {
00225             *direction = gpio_desc_extra->direction;
00226         }
00227 
00228         return SUCCESS;
00229     }
00230 
00231     return FAILURE;
00232 }
00233 
00234 
00235 /**
00236  * @brief Set the value of the specified GPIO.
00237  * @param desc - The GPIO descriptor.
00238  * @param value - The value.
00239  *                Example: GPIO_HIGH
00240  *                         GPIO_LOW
00241  * @return SUCCESS in case of success, FAILURE otherwise.
00242  */
00243 int32_t gpio_set_value(struct gpio_desc *desc, uint8_t value)
00244 {
00245     DigitalOut *gpio_output;        // pointer to gpio output object
00246     mbed_gpio_desc *gpio_desc_extra;    // pointer to gpio desc extra parameters
00247 
00248     if(desc && desc->extra) {
00249         gpio_desc_extra = (mbed_gpio_desc *)(desc->extra);
00250 
00251         if (gpio_desc_extra->gpio_pin) {
00252             gpio_output = (DigitalOut *)((mbed_gpio_desc *)desc->extra)->gpio_pin;
00253             gpio_output->write(value);
00254         }
00255 
00256         return SUCCESS;
00257     }
00258 
00259     return FAILURE;
00260 }
00261 
00262 
00263 /**
00264  * @brief Get the value of the specified GPIO.
00265  * @param desc - The GPIO descriptor.
00266  * @param value - The value.
00267  *                Example: GPIO_HIGH
00268  *                         GPIO_LOW
00269  * @return SUCCESS in case of success, FAILURE otherwise.
00270  */
00271 int32_t gpio_get_value(struct gpio_desc *desc, uint8_t *value)
00272 {
00273     DigitalIn *gpio_input;      // pointer to gpio input object
00274     uint8_t returnVal = FAILURE;
00275 
00276     if (desc && desc->extra) {
00277         gpio_input = (DigitalIn *)((mbed_gpio_desc *)desc->extra)->gpio_pin;
00278         *value = (uint8_t)gpio_input->read();
00279         returnVal = gpio_input->is_connected() ? SUCCESS : FAILURE;
00280 
00281         return returnVal;
00282     }
00283 
00284     return FAILURE;
00285 }
00286 
00287 #ifdef __cplusplus
00288 }
00289 #endif //  _cplusplus