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/*
* Author: Brendan Le Foll <brendan.le.foll@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.
*/
#pragma once
#include "spi.h"
#include "types.hpp"
#include <stdexcept>
namespace mraa
{
/**
* MRAA SPI Modes
*/
typedef enum {
SPI_MODE0 = 0, /**< CPOL = 0, CPHA = 0, Clock idle low, data is clocked in on rising edge,
output data (change) on falling edge */
SPI_MODE1 = 1, /**< CPOL = 0, CPHA = 1, Clock idle low, data is clocked in on falling edge,
output data (change) on rising edge */
SPI_MODE2 = 2, /**< CPOL = 1, CPHA = 0, Clock idle low, data is clocked in on falling edge,
output data (change) on rising edge */
SPI_MODE3 = 3, /**< CPOL = 1, CPHA = 1, Clock idle low, data is clocked in on rising, edge
output data (change) on falling edge */
} Spi_Mode;
/**
* @brief API to Serial Peripheral Interface
*
* This file defines the SPI interface for libmraa
*
* @snippet Spi-pot.cpp Interesting
*/
class Spi
{
public:
/**
* Initialise SPI object using the board mapping to set muxes
*
* @param bus to use, as listed in the platform definition, normally 0
*/
Spi(int bus)
{
m_spi = mraa_spi_init(bus);
if (m_spi == NULL) {
throw std::invalid_argument("Error initialising SPI bus");
}
}
Spi(int bus, int cs)
{
m_spi = mraa_spi_init_raw(bus, cs);
if (m_spi == NULL) {
throw std::invalid_argument("Error initialising SPI bus");
}
}
/**
* Closes spi bus
*/
~Spi()
{
mraa_spi_stop(m_spi);
}
/**
* Set the SPI device mode. see spidev0-3
*
* @param mode the mode. See Linux spidev doc
* @return Result of operation
*/
Result
mode(Spi_Mode mode)
{
return (Result) mraa_spi_mode(m_spi, (mraa_spi_mode_t) mode);
}
/**
* Set the SPI device operating clock frequency
*
* @param hz the frequency to set in hz
* @return Result of operation
*/
Result
frequency(int hz)
{
return (Result) mraa_spi_frequency(m_spi, hz);
}
/**
* Write single byte to the SPI device
*
* @param data the byte to send
* @return data received on the miso line or -1 in case of error
*/
int
writeByte(uint8_t data)
{
return mraa_spi_write(m_spi, (uint8_t) data);
}
/**
* Write single byte to the SPI device
*
* @param data the byte to send
* @return data received on the miso line
*/
uint16_t
write_word(uint16_t data)
{
return mraa_spi_write_word(m_spi, (uint16_t) data);
}
/**
* Write buffer of bytes to SPI device The pointer return has to be
* free'd by the caller. It will return a NULL pointer in cases of
* error
*
* @param txBuf buffer to send
* @param length size of buffer to send
* @return uint8_t* data received on the miso line. Same length as passed in
*/
uint8_t*
write(uint8_t* txBuf, int length)
{
return mraa_spi_write_buf(m_spi, txBuf, length);
}
#ifndef SWIG
/**
* Write buffer of bytes to SPI device The pointer return has to be
* free'd by the caller. It will return a NULL pointer in cases of
* error
*
* @param txBuf buffer to send
* @param length size of buffer (in bytes) to send
* @return uint8_t* data received on the miso line. Same length as passed in
*/
uint16_t*
write_word(uint16_t* txBuf, int length)
{
return mraa_spi_write_buf_word(m_spi, txBuf, length);
}
#endif
#ifndef SWIG
/**
* Transfer data to and from SPI device Receive pointer may be null if
* return data is not needed.
*
* @param txBuf buffer to send
* @param rxBuf buffer to optionally receive data from spi device
* @param length size of buffer to send
* @return Result of operation
*/
Result
transfer(uint8_t* txBuf, uint8_t* rxBuf, int length)
{
return (Result) mraa_spi_transfer_buf(m_spi, txBuf, rxBuf, length);
}
/**
* Transfer data to and from SPI device Receive pointer may be null if
* return data is not needed.
*
* @param txBuf buffer to send
* @param rxBuf buffer to optionally receive data from spi device
* @param length size of buffer to send
* @return Result of operation
*/
Result
transfer_word(uint16_t* txBuf, uint16_t* rxBuf, int length)
{
return (Result) mraa_spi_transfer_buf_word(m_spi, txBuf, rxBuf, length);
}
#endif
/**
* Change the SPI lsb mode
*
* @param lsb Use least significant bit transmission - 0 for msbi
* @return Result of operation
*/
Result
lsbmode(bool lsb)
{
return (Result) mraa_spi_lsbmode(m_spi, (mraa_boolean_t) lsb);
}
/**
* Set bits per mode on transaction, default is 8
*
* @param bits bits per word
* @return Result of operation
*/
Result
bitPerWord(unsigned int bits)
{
return (Result) mraa_spi_bit_per_word(m_spi, bits);
}
private:
mraa_spi_context m_spi;
};
}
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