File content as of revision 0:85855ecd3257:

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/*!
 ******************************************************************************
 * @file:
 * @brief:  ADISENSE OS-dependent wrapper layer for SPI interface
 *-----------------------------------------------------------------------------
 */

#include <mbed.h>

#include "inc/adi_sense_spi.h"
#include "inc/adi_sense_log.h"

#define ADI_SENSE_SPI_MODE       0 /* CPOL=0, CPHA=0 */
#define ADI_SENSE_SPI_FRAME_SIZE 8 /* 8-bit frame size */

class SpiContext
{
public:
    SpiContext(
        PinName mosiPin,
        PinName misoPin,
        PinName sckPin,
        PinName csPin,
        unsigned maxSpeed);

    int transfer(
        void *pTxData,
        void *pRxData,
        unsigned nLength,
        bool bCsHold);

private:
    SPI _spi;
    DigitalOut _cs;
};

SpiContext::SpiContext(PinName mosiPin,
                       PinName misoPin,
                       PinName sckPin,
                       PinName csPin,
                       unsigned maxSpeed)
    : _spi(mosiPin, misoPin, sckPin),
      _cs(csPin, 1)
{

    _spi.format(ADI_SENSE_SPI_FRAME_SIZE, ADI_SENSE_SPI_MODE);
    _spi.frequency(maxSpeed);
}

int SpiContext::transfer(
    void *pTxData,
    void *pRxData,
    unsigned nLength,
    bool bCsHold)
{
    int rc = 0;

    _cs = 0;

    rc  = _spi.write((char*)(pTxData), pTxData ? nLength : 0,
                     (char*)(pRxData), pRxData ? nLength : 0);
    
    if ((rc < 0) || !bCsHold)
        _cs = 1;

    return rc;
}

#ifdef __cplusplus
extern "C" {
#endif

/*
 * Open the SPI interface and allocate resources
 */
ADI_SENSE_RESULT adi_sense_SpiOpen(
    ADI_SENSE_PLATFORM_SPI_CONFIG *pConfig,
    ADI_SENSE_SPI_HANDLE *phDevice)
{
    SpiContext *pCtx = new SpiContext((PinName)pConfig->mosiPin,
                                      (PinName)pConfig->misoPin,
                                      (PinName)pConfig->sckPin,
                                      (PinName)pConfig->csPin,
                                      pConfig->maxSpeedHz);
    if (!pCtx)
    {
        ADI_SENSE_LOG_ERROR("Failed to allocate memory for SPI interface");
        return ADI_SENSE_NO_MEM;
    }

    *phDevice = reinterpret_cast<ADI_SENSE_SPI_HANDLE>(pCtx);
    return ADI_SENSE_SUCCESS;
}

/*
 * Execute a bi-directional data transfer on the SPI interface
 */
ADI_SENSE_RESULT
adi_sense_SpiTransfer(
    ADI_SENSE_SPI_HANDLE hDevice,
    void *pTxData,
    void *pRxData,
    unsigned nLength,
    bool bCsHold)
{
    SpiContext *pCtx = reinterpret_cast<SpiContext *>(hDevice);

    if (pCtx->transfer(pTxData, pRxData, nLength, bCsHold) < 0)
    {
        ADI_SENSE_LOG_ERROR("Failed to complete SPI transfer");
        return ADI_SENSE_FAILURE;
    }

    return ADI_SENSE_SUCCESS;
}

/*
 * Close the SPI interface and free resources
 */
void adi_sense_SpiClose(
    ADI_SENSE_SPI_HANDLE hDevice)
{
    SpiContext *pCtx = reinterpret_cast<SpiContext *>(hDevice);

    delete pCtx;
}

#ifdef __cplusplus
}
#endif

/*!
 * @}
 */