linux2.6字符设备的标准注册方法

关于字符设备的注册，标准的2.6中可以这样做：

static struct cdev dev;
static int wmsc_dev_init(void)
{
    int ret;
      dev_id = MKDEV(DEV_MAJOR,0);
      ret = register_chrdev_region(dev_id,1,DEV_NAME);
      if(ret < 0){
        printk(KERN_ERR"Can't register device,maybe the device id has been used.\n");
        unregister_chrdev_region(dev_id,1);
        return ret;
      }
      cdev_init(&dev,&fops);
      ret = cdev_add(&dev,dev_id,1);
      if(ret < 0){
           printk(KERN_ERR"Can't add device.\n");
        cdev_del(&dev);
        return ret;
      }
      return 0;
}

#define DEV_MAJOR 178
#define DEV_NAME  "gpio"

static struct file_operations fops = {
    .open = wmrc_open,
      .read = wmrc_read,
      .write = wmrc_write,
      .ioctl = wmrc_ioctl,
      .owner = THIS_MODULE,
};

后面就是些设备加载，和节点创建等，如下：

insmod xx.ko

mknod /dev/gpio     c 177 0
chmod 766 /dev/gpio

这些流程是挺正确的，也有固定的流程，不用深归内部的原理，制作驱动还是要深入的算法里面的。