#include <sys/ioctl.h>
#include <linux/spi/spidev.h>
#include <errno.h>
#include <fcntl.h>    /* For O_RDWR */
#include <unistd.h>   /* For open(), creat() */
#include <cstdio>     /* For printf() */


int main(int argc, char *argv[])
{
    printf("version: %d\n", 7);

    int fd = 0;
    fd = open("/dev/spidev3.0", O_RDWR);
    if (fd < 0)
    {
        printf("SPI : can't open device");
        return -1;
    }

    bool ret = ioctl(fd, SPI_IOC_WR_MODE, SPI_MODE_2);
    if (ret == -1)
    {
        printf("SPI : can't set spi mode");
        close(fd);
        return 1;
    }

    ret = ioctl(fd, SPI_IOC_WR_LSB_FIRST, SPI_LSB_FIRST);
    if (ret == -1)
    {
        printf("SPI : can't set spi LSB_FIRST mode");
        close(fd);
        return 1;
    }

    ret = ioctl(fd, SPI_IOC_WR_MAX_SPEED_HZ, 7000);
    if (ret == -1)
    {
        printf("SPI : can't set spi MAX_SPEED mode");
        close(fd);
        return 1;
    }

    {
        unsigned char spiData[4];
        spiData[0] = 0b00001111; // 0x0F read
        spiData[1] = 0b00000000; // 0x00 msB Address
        spiData[2] = 0b00001000; // 0x08 lsB Address
        spiData[3] = 0b00000000; // 0x00 data byte

        for(int j = 0; j < 500; j++)
        {
            for(int i = 0; i < 6; i++)
            {
                if(spiData[2] == 0xFF)
                {
                    spiData[2] = 0;
                }
                spiData[2] = spiData[2] + 1; // first register read is 0x09
                spiData[3] = 0b00000000;

                struct spi_ioc_transfer mesg;

                mesg.tx_buf = (unsigned long)spiData;
                mesg.rx_buf = (unsigned long)spiData;
                mesg.len = 4;
                mesg.bits_per_word = 8;

                ret = ioctl(fd, SPI_IOC_MESSAGE(1), mesg);
                if (ret < 0)
                {
                    printf("SPI : failed transaction");
                    close(fd);
                    return 1;
                }

                printf("MAC %d %d: %02X %02X %02X %02X\n", i, j, spiData[0], spiData[1], spiData[2], spiData[3]);
            }
        }
    }

    close(fd);
}