QuadSpiInterface.cpp

00001 /*******************************************************************************
00002  * Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved.
00003  *
00004  * Permission is hereby granted, free of charge, to any person obtaining a
00005  * copy of this software and associated documentation files (the "Software"),
00006  * to deal in the Software without restriction, including without limitation
00007  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
00008  * and/or sell copies of the Software, and to permit persons to whom the
00009  * Software is furnished to do so, subject to the following conditions:
00010  *
00011  * The above copyright notice and this permission notice shall be included
00012  * in all copies or substantial portions of the Software.
00013  *
00014  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
00015  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
00016  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
00017  * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
00018  * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
00019  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
00020  * OTHER DEALINGS IN THE SOFTWARE.
00021  *
00022  * Except as contained in this notice, the name of Maxim Integrated
00023  * Products, Inc. shall not be used except as stated in the Maxim Integrated
00024  * Products, Inc. Branding Policy.
00025  *
00026  * The mere transfer of this software does not imply any licenses
00027  * of trade secrets, proprietary technology, copyrights, patents,
00028  * trademarks, maskwork rights, or any other form of intellectual
00029  * property whatsoever. Maxim Integrated Products, Inc. retains all
00030  * ownership rights.
00031  *******************************************************************************
00032  */
00033 #include "QuadSpiInterface.h"
00034 
00035 /**
00036 * @brief Constructor that accepts pin names for the QUAD SPI interface
00037 * @param mosi master out slave in pin name
00038 * @param miso master in slave out pin name
00039 * @param sclk serial clock pin name
00040 * @param cs chip select pin name
00041 */
00042 QuadSpiInterface::QuadSpiInterface(PinName mosi, PinName miso, PinName sclk,
00043                                    PinName cs)
00044     : spi(mosi, miso, sclk), csPin(cs) {
00045 
00046     }
00047 
00048 /**
00049 * @brief Transmit and recieve QUAD SPI data
00050 * @param tx_buf pointer to transmit byte buffer
00051 * @param tx_size number of bytes to transmit
00052 * @param rx_buf pointer to the recieve buffer
00053 * @param rx_size number of bytes to recieve
00054 * @param last flag to indicate if this is the last QUAD SPI transaction for the
00055 * current chip select cycle
00056 */
00057 int QuadSpiInterface::SPI_Transmit(const uint8_t *tx_buf, uint32_t tx_size,
00058                                    uint8_t *rx_buf, uint32_t rx_size,
00059                                    int last) {
00060   uint32_t i;
00061   int result = 0;
00062   int index = 0;
00063   // lower chip select
00064   csPin = 0;
00065   // write bytes out QUAD SPI
00066   spi.setQuadMode();
00067   for (i = 0; i < tx_size; i++) {
00068     rx_buf[index] = spi.write((int)tx_buf[i]);
00069     index++;
00070   }
00071   // read in bytes from QUAD SPI
00072   for (i = 0; i < rx_size; i++) {
00073     rx_buf[index] = (uint8_t)spi.read();
00074     index++;
00075   }
00076   // raise chip select if this is the last transaction
00077     if (last) csPin = 1;
00078   return result;
00079 }
00080 
00081 /**
00082 * @brief Transmit and recieve QUAD SPI data
00083 * @param tx_buf pointer to transmit byte buffer
00084 * @param tx_size number of bytes to transmit
00085 * @param rx_buf pointer to the recieve buffer
00086 * @param rx_size number of bytes to recieve
00087 * @param last flag to indicate if this is the last QUAD SPI transaction for the
00088 * current chip select cycle
00089 */
00090 int QuadSpiInterface::SPI_Transmit4Wire(const uint8_t *tx_buf, uint32_t tx_size,
00091                                         uint8_t *rx_buf, uint32_t rx_size,
00092                                         int last) {
00093   uint32_t i;
00094   int result = 0;
00095   int index = 0;
00096   // lower chip select
00097   csPin = 0;
00098   // write bytes out Single SPI
00099   spi.setSingleMode();
00100   for (i = 0; i < tx_size; i++) {
00101     rx_buf[index] = spi.write((int)tx_buf[i]);
00102     index++;
00103   }
00104   // raise chip select if this is the last transaction
00105     if (last) csPin = 1;
00106   return result;
00107 }
00108