Diff: src/spi.cpp

Revision:

8:70fc373a5f46

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/spi.cpp	Wed Feb 26 06:09:13 2020 +0000
@@ -0,0 +1,174 @@
+/***************************************************************************//**
+ *   @file   spi.cpp
+ *   @brief  Implementation of SPI No-OS platform driver interfaces
+********************************************************************************
+ * Copyright (c) 2019, 2020 Analog Devices, Inc.
+ *
+ * All rights reserved.
+ *
+ * This software is proprietary to Analog Devices, Inc. and its licensors.
+ * By using this software you agree to the terms of the associated
+ * Analog Devices Software License Agreement.
+*******************************************************************************/
+
+/******************************************************************************/
+/***************************** Include Files **********************************/
+/******************************************************************************/
+
+#include <stdio.h>
+#include <mbed.h>
+
+#include "platform_drivers.h"
+#include "spi_extra.h"
+
+/******************************************************************************/
+/********************** Macros and Constants Definitions **********************/
+/******************************************************************************/
+
+#define SEND_BYTE                      8
+
+/******************************************************************************/
+/********************** Variables and User defined data types *****************/
+/******************************************************************************/
+
+/******************************************************************************/
+/************************ Functions Declarations ******************************/
+/******************************************************************************/
+
+/******************************************************************************/
+/************************ Functions Definitions *******************************/
+/******************************************************************************/
+
+/**
+ * @brief Initialize the SPI communication peripheral.
+ * @param desc - The SPI descriptor.
+ * @param init_param - The structure that contains the SPI parameters.
+ * @return SUCCESS in case of success, FAILURE otherwise.
+ */
+int32_t spi_init_noos(struct spi_desc **desc,
+		      const struct spi_init_param *param)
+{
+	mbed::SPI *spi;		// pointer to new spi instance
+	DigitalOut *ss; 	// pointer to new SS instance
+	mbed_spi_desc *mbed_desc;	// Pointer to mbed spi descriptor
+
+	if (desc) {
+		// Create the spi description object for the device
+		spi_desc * new_desc = (spi_desc *)malloc(sizeof(spi_desc));
+		if (new_desc == NULL) {
+			return FAILURE;
+		}
+
+		new_desc->chip_select = param->chip_select;
+		new_desc->mode = param->mode;
+		new_desc->max_speed_hz = param->max_speed_hz;
+
+		// Configure and instantiate SPI protocol
+		spi = new SPI(
+			(PinName)(((mbed_spi_init_param *)param->extra)->spi_mosi_pin),
+			(PinName)(((mbed_spi_init_param *)param->extra)->spi_miso_pin),
+			(PinName)(((mbed_spi_init_param *)param->extra)->spi_clk_pin));
+
+		if (spi == NULL) {
+			return FAILURE;
+		}
+
+		// Configure and instantiate slave select pin
+		ss = new DigitalOut((PinName)(new_desc->chip_select));
+		if (ss == NULL) {
+			return FAILURE;
+		}
+
+		// Create the SPI extra descriptor object to store new SPI instances
+		mbed_desc = (mbed_spi_desc *)malloc(sizeof(mbed_spi_desc));
+		if (mbed_desc == NULL) {
+			return FAILURE;
+		}
+
+		mbed_desc->spi_port = (SPI *)spi;
+		mbed_desc->slave_select = (DigitalOut *)ss;
+		new_desc->extra = (mbed_spi_desc *)mbed_desc;
+
+		*desc = new_desc;
+
+		/**
+		    NOTE: Actual frequency of SPI clk will be somewhat device
+		    dependent, relating to clock-settings, prescalars etc. If absolute
+		    SPI frequency is required, consult your device documentation.
+		  **/
+		spi->frequency(param->max_speed_hz);
+		spi->format(SEND_BYTE, param->mode);       // Stick to byte-multiples
+		spi->set_default_write_value(0x00);        // code to write when reading back
+		ss->write(GPIO_HIGH);                      // set SS high
+
+		return SUCCESS;
+	}
+
+	return FAILURE;
+}
+
+
+/**
+ * @brief Free the resources allocated by spi_init().
+ * @param desc - The SPI descriptor.
+ * @return SUCCESS in case of success, FAILURE otherwise.
+ */
+int32_t spi_remove(struct spi_desc *desc)
+{
+	if (desc) {
+		// Free the SPI port object
+		if ((SPI *)(((mbed_spi_desc *)(desc->extra))->spi_port)) {
+			delete((SPI *)(((mbed_spi_desc *)(desc->extra))->spi_port));
+		}
+
+		// Free the SS port object
+		if ((DigitalOut *)(((mbed_spi_desc *)(desc->extra))->slave_select)) {
+			delete((DigitalOut *)(((mbed_spi_desc *)(desc->extra))->slave_select));
+		}
+
+		// Free the SPI extra descriptor object
+		if ((mbed_spi_desc *)(desc->extra)) {
+			free((mbed_spi_desc *)(desc->extra));
+		}
+
+		// Free the SPI descriptor object
+		free(desc);
+
+		return SUCCESS;
+	}
+
+	return FAILURE;
+}
+
+
+/**
+ * @brief Write and read data to/from SPI.
+ * @param desc - The SPI descriptor.
+ * @param data - The buffer with the transmitted/received data.
+ * @param bytes_number - Number of bytes to write/read.
+ * @return SUCCESS in case of success, FAILURE otherwise.
+ */
+int32_t spi_write_and_read(struct spi_desc *desc,
+			   uint8_t *data,
+			   uint16_t bytes_number)
+{
+	mbed::SPI *spi; 	// pointer to new spi instance
+	DigitalOut *ss;  	// pointer to new SS instance
+
+	if (desc) {
+		spi = (SPI *)(((mbed_spi_desc *)(desc->extra))->spi_port);
+		ss = (DigitalOut *)(((mbed_spi_desc *)(desc->extra))->slave_select);
+
+		ss->write(GPIO_LOW);
+
+		for (size_t byte = 0 ; byte < bytes_number ; byte++) {
+			data[byte] =  spi->write(data[byte]);
+		}
+
+		ss->write(GPIO_HIGH);
+
+		return SUCCESS;
+	}
+
+	return FAILURE;
+}