[linux/应用]SPI通讯应用

代码主要应用于spi通讯测试

源码

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
 
#include "Debug.h"

#define SPI_DEBUG 0
 
// static const char *device = "/dev/spidev2.0";
static uint8_t mode = 0; 
static uint8_t bits = 8; 
static uint32_t speed = 12 * 1000 * 1000;
static uint16_t delay = 0;
static int g_SPI_Fd = 0;

unsigned char r_buf[256];
unsigned char w_buf[256];

static void pabort(const char *s)
{
    perror(s);
    abort();
}
 
int SPI_Transfer(const uint8_t *TxBuf, uint8_t *RxBuf, int len)
{
    int ret;
    int fd = g_SPI_Fd;
 
    struct spi_ioc_transfer tr =    {
            .tx_buf = (unsigned long) TxBuf,
            .rx_buf = (unsigned long) RxBuf,
            .len =    len,
            .speed_hz = 0,

            .delay_usecs = delay,
            .bits_per_word = 2
    };
 
    ret = ioctl(fd, SPI_IOC_MESSAGE(1), &tr);
    if (ret < 1)
        pr_err("can't send spi message");
    else
    {
#if SPI_DEBUG
        int i;
        pr_debug("nsend spi message Succeed");
        pr_debug("nSPI Send [Len:%d]: ", len);
        for (i = 0; i < len; i++)
        {
            if (i % 8 == 0)
            printf("nt");
            printf("0x%02X ", TxBuf[i]);
        }
        printf("n");
 
        pr_debug("SPI Receive [len:%d]:", len);
        for (i = 0; i < len; i++)
        {
            if (i % 8 == 0)
            printf("nt");
            printf("0x%02X ", RxBuf[i]);
        }
        printf("n");
#endif
    }
    return ret;
}
 

int SPI_Write(uint8_t *TxBuf, int len)
{
    int ret;
    int fd = g_SPI_Fd;
 
    ret = write(fd, TxBuf, len);
    if (ret < 0)
        pr_err("SPI Write errorn");
    else
    {
#if SPI_DEBUG
        int i;
        pr_debug("nSPI Write [Len:%d]: ", len);
        for (i = 0; i < len; i++)
        {
            if (i % 8 == 0)
            printf("nt");
            printf("0x%02X ", TxBuf[i]);
        }
        printf("n");
 
#endif
    }
 
    return ret;
}
 
int SPI_Read(uint8_t *RxBuf, int len)
{
    int ret;
    int fd = g_SPI_Fd;
    ret = read(fd, RxBuf, len);
    if (ret < 0)
        pr_err("SPI Read errorn");
    else
    {
#if SPI_DEBUG
        int i;
        pr_debug("SPI Read [len:%d]:", len);
        for (i = 0; i < len; i++)
        {
            if (i % 8 == 0)
            printf("nt");
            printf("0x%02X ", RxBuf[i]);
        }
        printf("n");
#endif
    }
 
    return ret;
}
 
int SPI_Open_(const char* device)
{
    int fd;
    int ret = 0;
 
    if (g_SPI_Fd != 0) 
        return 0xF1;
 
    fd = open(device, O_RDWR);
    if (fd < 0)
        pabort("can't open device");
    else
        pr_debug("SPI - Open Succeed. Start Init SPI...n");
 
    g_SPI_Fd = fd;
    
    ret = ioctl(fd, SPI_IOC_WR_MODE, &mode);
    if (ret == -1)
        pabort("can't set spi mode");
 
    ret = ioctl(fd, SPI_IOC_RD_MODE, &mode);
    if (ret == -1)
        pabort("can't get spi mode");
 
    
    ret = ioctl(fd, SPI_IOC_WR_BITS_PER_WORD, &bits);
    if (ret == -1)
        pabort("can't set bits per word");
 
    ret = ioctl(fd, SPI_IOC_RD_BITS_PER_WORD, &bits);
    if (ret == -1)
        pabort("can't get bits per word");
 
    
    ret = ioctl(fd, SPI_IOC_WR_MAX_SPEED_HZ, &speed);
    if (ret == -1)
        pabort("can't set max speed hz");
 
    ret = ioctl(fd, SPI_IOC_RD_MAX_SPEED_HZ, &speed);
    if (ret == -1)
        pabort("can't get max speed hz");
 
    pr_debug("spi mode: %dn", mode);
    pr_debug("bits per word: %dn", bits);
    pr_debug("max speed: %d KHz (%d MHz)n", speed / 1000, speed / 1000 / 1000);
 
    return ret;
}
 

int SPI_Close(void)
{
    int fd = g_SPI_Fd;
 
    if (fd == 0) 
        return 0;
    close(fd);
    g_SPI_Fd = 0;
 
    return 0;
}
 
int SPI_LookBackTest(void)
{
    int ret, i;
    const int BufSize = 16;
    uint8_t tx[BufSize], rx[BufSize];
 
    bzero(rx, sizeof(rx));
    for (i = 0; i < BufSize; i++)
        tx[i] = i;
 
    pr_debug("nSPI - LookBack Mode Test...n");
    ret = SPI_Transfer(tx, rx, BufSize);
    if (ret > 1)
    {
        ret = memcmp(tx, rx, BufSize);
        if (ret != 0)
        {
            pr_err("LookBack Mode Test errorn");
//            pabort("error");
        }
        else
            pr_debug("SPI - LookBack Mode  OKn");
    }
 
    return ret;
}