android 下I2C驱动的例子

#ifndef _RWI2C_C_
#define _RWI2C_C_




#include  
#include  
#include  
#include  
#include  
#include  
#include  
#include
#include




#define RWI2C_DEVICE_NAME "rwi2c"








/* 打开设备方法 */  
static int rwi2c_open(struct inode *inode, struct file *filp)  
{  


printk(KERN_ALERT"NY::rwi2c_open.\n");
      
    return 0;  
}  
  
/* 设备文件释放时调用，空实现 */  
static int rwi2c_release(struct inode *inode, struct file *filp)  
{  
printk(KERN_ALERT"NY::rwi2c_release.\n");
    return 0;  
}  
  
/* 读取设备的寄存器val值 */  
static ssize_t rwi2c_read(struct file *filp, char __user *buf, size_t count, loff_t *f_pos)  
{  
    ssize_t err = 0;  


printk(KERN_ALERT"NY::rwi2c_read.\n");
    return err;  
}  
  
/* 写设备的寄存器val的值 */  
static ssize_t rwi2c_write(struct file *filp, const char __user *buf, size_t count, loff_t *f_pos)  
{  
    ssize_t err = 0;  


printk(KERN_ALERT"NY::rwi2c_write.\n");
    return err;  
}  


/* 传统的设备文件操作方法表 */  
static struct file_operations rwi2c_fops = {  
    .owner = THIS_MODULE,  
    .open  = rwi2c_open,  
    .release = rwi2c_release,  
    .read  = rwi2c_read,  
    .write = rwi2c_write,  
};  
 
static struct miscdevice rwi2c_misc = {
.minor = MISC_DYNAMIC_MINOR,
.name = RWI2C_DEVICE_NAME,
.fops = &rwi2c_fops,
};




static int __init rwi2c_init(void)
{
int ret= 0;
printk(KERN_ALERT"Initializing rwi2c device.\n"); 


ret = misc_register(&rwi2c_misc);

printk(KERN_ALERT"Succedded to initialize rwi2c device.\n");


  return ret;
}
module_init(rwi2c_init);


static void __exit rwi2c_exit(void)
{
misc_deregister(&rwi2c_misc);


}
module_exit(rwi2c_exit);


MODULE_AUTHOR("[e-mail]>");
MODULE_DESCRIPTION("ROCKCHIP I2C DEV Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("i2c:rwi2c");












给驱动节点更改权限：
在android目录文件里system/core/rootdir/ueventd.rc 
添加
# niuyi
/dev/rwi2c                0666   root       root