给我写个liteos -a 下的i2c驱动

好的，以下是一个简单的 liteos -a 下的 i2c 驱动代码示例：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <linux/i2c-dev.h>

#define I2C_BUS "/dev/i2c-0"
#define I2C_SLAVE_ADDRESS 0x53

int main() {
    int file;
    char *filename = I2C_BUS;
    int addr = I2C_SLAVE_ADDRESS;
    char buf[10];
    char reg = 0x00;

    if ((file = open(filename, O_RDWR)) < 0) {
        perror("Failed to open the bus.");
        exit(1);
    }

    if (ioctl(file, I2C_SLAVE, addr) < 0) {
        perror("Failed to connect to the sensor.");
        exit(1);
    }

    buf[0] = reg;
    if ((write(file, buf, 1)) != 1) {
        perror("Failed to set the register.");
        exit(1);
    }

    if (read(file, buf, 1) != 1) {
        perror("Failed to read the device.");
        exit(1);
    } else {
        printf("The value is 0x%02x.\n", buf[0]);
    }

    close(file);

    return 0;
}

希望对您有所帮助！