LinuxCNC-RIO - RealtimeIO for LinuxCNC based on FPGA (ICE40 / ECP5)

/*
    interface: SPI
*/

#include <linux/spi/spidev.h>
#include <sys/ioctl.h>  
int spifd;
static uint8_t mode = SPI_MODE_0;
static uint8_t bits = 8;
static uint32_t speed = 1500000;
int spi_init(void) {
   
    rtapi_print("Info: Initialize SPI5 connection\n");
    spifd = open("/dev/spidev0.0", O_RDWR);
    if (spifd < 0) {
        rtapi_print_msg(RTAPI_MSG_ERR,"Failed to open SPI device\n");
        return -1;
    }
    // Set SPI mode
    if (ioctl(spifd, SPI_IOC_WR_MODE, &mode) == -1) {
        rtapi_print_msg(RTAPI_MSG_ERR,"Failed to set SPI mode\n");
        close(spifd);
        return -1;
    }
    // Set bits per word
    if (ioctl(spifd, SPI_IOC_WR_BITS_PER_WORD, &bits) == -1) {
        rtapi_print_msg(RTAPI_MSG_ERR,"Failed to set bits per word\n");
        close(spifd);
        return -1;
    }
    // Set max speed
    if (ioctl(spifd, SPI_IOC_WR_MAX_SPEED_HZ, &speed) == -1) {
        rtapi_print_msg(RTAPI_MSG_ERR,"Failed to set max speed\n");
        close(spifd);
        return -1;
    }
}
int spi_trx(uint8_t *txBuffer, uint8_t *rxBuffer, uint16_t size) {
        struct spi_ioc_transfer tr = {
        .tx_buf = (uint64_t)txBuffer,
        .rx_buf = (uint64_t)rxBuffer,
        .len = size,
        .speed_hz = speed,
        .delay_usecs = 0,
        .bits_per_word = bits,
    };
    // Perform SPI transfer
    if (ioctl(spifd, SPI_IOC_MESSAGE(1), &tr) == -1) {
rtapi_print_msg(RTAPI_MSG_ERR,"Failed to perform SPI transfer\n");
    }
    return 1;
}

int interface_init(void)  {
     spi_init();
}

/*
   hal functions
*/

//ADD to rtapi_app_exit ->> close(spifd);
void rtapi_app_exit(void) {
    close(spifd);
    hal_exit(comp_id);
}

"rpi5": true,

{
"name": "IceShield",
"description": "RIO-IceShield on Raspberry PI5",
"boardcfg": "IceShield",
"protocol": "SPI",
"rpi5": true,
....