///////////////////////////////////////////////////////////////////////////////////////
// File          SPI.xs
// Description:  XS module for HiPi::Device::SPI
// Copyright:    Copyright (c) 2013-2017 Mark Dootson
// License:      This is free software; you can redistribute it and/or modify it under
//               the same terms as the Perl 5 programming language system itself.
///////////////////////////////////////////////////////////////////////////////////////

#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"
#include "mylib/include/ppport.h"
#include <sys/ioctl.h>
#include <linux/spi/spidev.h>

MODULE = HiPi::Device::SPI  PACKAGE = HiPi::Device::SPI

void
_transfer_data(file, inbuf, delay = 0, speed = 1000000, bitspw = 8 )
    int file
    SV* inbuf
    __u16 delay
    __u32 speed
    __u8 bitspw
  PPCODE:
    struct spi_ioc_transfer msg;
    memset (&msg, 0, sizeof(msg));
    SV* outbuf = newSVsv(inbuf);
    
    msg.tx_buf        = (intptr_t)SvPVX(inbuf);
    msg.rx_buf        = (intptr_t)SvPVX(outbuf);
    msg.len           = (__u32)SvCUR(inbuf);
    msg.speed_hz      = speed;
    msg.delay_usecs   = delay;
    msg.bits_per_word = bitspw;
    
##//  msg.cs_change:1
##//  msg.pad
    
    int ioval = ioctl (file, SPI_IOC_MESSAGE(1), &msg);
    if( ioval >= 0)
    {
        EXTEND(SP, 1);
        PUSHs(sv_2mortal(outbuf));
    }
    else
    {
        EXTEND(SP, 1);
        PUSHs(&PL_sv_undef);
    }
  

int
_set_spi_max_speed(file, speed)
    int file
    __u32 speed
  CODE:
    int rval;
    rval = ioctl(file, SPI_IOC_WR_MAX_SPEED_HZ, &speed);
    if( rval < 0 )
        rval = -1;
    
    RETVAL = rval;
  OUTPUT: RETVAL

int
_get_spi_max_speed(file)
    int file
  CODE:
    __u32 speed;
    int rval;
    rval = ioctl(file, SPI_IOC_RD_MAX_SPEED_HZ, &speed);

    if( rval < 0 ) {
        RETVAL = -1;
    } else {
        RETVAL = speed;
    }

  OUTPUT: RETVAL

int
_set_spi_mode(file, mode)
    int file
    __u8 mode
  CODE:
    int rval;
    rval = ioctl(file, SPI_IOC_WR_MODE, &mode);
    
    if( rval < 0 )
        rval = -1;
    
    RETVAL = rval;
  OUTPUT: RETVAL

int
_get_spi_mode(file)
    int file
  CODE:
    int rval;
    __u8 mode;
    rval = ioctl(file, SPI_IOC_RD_MODE, &mode);
    if( rval < 0 ) {
        RETVAL = -1;
    } else {
        RETVAL = mode;
    }
  OUTPUT: RETVAL

int
_set_spi_bits_per_word(file, bitspw)
    int file
    __u8 bitspw
  CODE:
    int rval;
    rval = ioctl(file, SPI_IOC_WR_BITS_PER_WORD, &bitspw);

    if( rval < 0 )
        rval = -1;
    
    RETVAL = rval;
  OUTPUT: RETVAL

int
_get_spi_bits_per_word(file)
    int file
    
  CODE:
    int rval;
    __u8 bitspw;
    rval = ioctl(file, SPI_IOC_RD_BITS_PER_WORD, &bitspw);
    if( rval < 0 ) {
        RETVAL = -1;
    } else {
        RETVAL = bitspw;
    }
  OUTPUT: RETVAL