cat1025.c

这是pxa270的I2c驱动程序

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <fcntl.h>            /* 文件操作 */
#include <sys/ioctl.h>        /* ioctl()函数 */
//#include "/pxa270/kernel-test/linux-2.6.18/include/linux/i2c.h" /* I2C总线控制器驱动命令 */
#include "i2c.h"
#define	 I2C_ADDR 	0xA0     /* CAT1025 从机地址 */

int main()
{
    int fd, ret, i, num;
    unsigned int suba;
    unsigned char buf[257] = {0xFF,0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,
			           0x09,0x0A,0x0B,0x0C,0x0D,0x0E,0x0F,0x00};
    //char s;

    fd = open("/dev/i2c-0", O_RDWR);              /* 打开设备 */
    if(fd == -1)
    {
        printf("\nFailed to open i2c-0!\n");
        exit(-1);
    } 

    printf("********************************\n");
    printf("* ==== CAT1025 Information === *\n");
    printf("* SLAVE ADDRESS : 0xA0         *\n");
    printf("* TOTAL BYTES   : 512 Bytes    *\n");
    printf("* PAGE SIZE     : 16  Bytes    *\n");
    printf("********************************\n");

    ret = ioctl(fd, I2C_TENBIT, 0);               /* 指定从机地址为7bit */
    if (ret != 0)
    {
    	printf("\nCan't set I2C address bit number.\n");
    	close(fd);
    	exit(-1);
    }
 
    ret = ioctl(fd, I2C_SLAVE, I2C_ADDR >> 1); /* 设置从机地址,7位地址,须右移1位*/
    if (ret != 0)
    {
    	printf("\nCan't set I2C slave device address.\n");
    	close(fd);
    	exit(-1);
    }
        
    printf("\n ==== Start Write CAT1025 ====\n"); 
    printf("Please Input the SUB-ADDRESS you will write(Hex):");
    scanf("%x", &suba);
    printf("SUB-ADDRESS suba = 0x%02x\n", suba);
    buf[0] = suba;
    printf("Please Input the Bytes Numbers you want to write(Hex):");
    scanf("%x", &num);
    printf("Bytes Numbers num  = 0x%02x\n", num);

    printf("Writing 0x%02x Bytes to CAT1025 from 0x%02x\n", num, suba);

    for (i = 1; i < num+1; i++)
       printf("0x%02x ", buf[i]);
  
    /* Start write CAT1025 */
    ret = write(fd, buf, num+1);  /* 写num个字节到CAT1025,第1字节为子地址 */
    if (ret != num+1)
    {
    	printf("Write CAT1025 failed.\n");
    	close(fd);
    	exit(-1);
    }
    
    usleep(10000);                      /* 等待10ms写入完成 */
    
//    printf("\n\n ==== Read All Data in CAT1025 ====\n");	
//    suba = 0;
    ret = write(fd, &suba, 1);		  /* 发送从机子地址 */
    if (ret != 1)
    {
    	printf("\nSend slave address failed.\n");
    	close(fd);
    	exit(-1);
    }   	
    
    printf("Read 0x%02x Bytes from 0x%02x in CAT1025.\n", num, suba);
    ret = read(fd, &buf, num);  	  
    if (ret == num)
    {
       for (i = 0; i < num; i++)
           printf("0x%02x ", buf[i]);
    }
    else
        {
    	    printf("\nRead CAT1025 failed.\n");
    	    close(fd);
    	    exit(-1);   		
   	}
    printf("\nPlease Verify the data.\n");

    close(fd);
    return 0;
}