设备树的结构体

struct device_node {
	const char *name;
	const char *type;
	phandle phandle;
	const char *full_name;
	struct fwnode_handle fwnode;

	struct	property *properties;
	struct	property *deadprops;	/* removed properties */
	struct	device_node *parent;
	struct	device_node *child;
	struct	device_node *sibling;
#if defined(CONFIG_OF_KOBJ)
	struct	kobject kobj;
#endif
	unsigned long _flags;
	void	*data;
#if defined(CONFIG_SPARC)
	const char *path_component_name;
	unsigned int unique_id;
	struct of_irq_controller *irq_trans;
#endif
};

struct property {
	char	*name;
	int	length;
	void	*value;
	struct property *next;
#if defined(CONFIG_OF_DYNAMIC) || defined(CONFIG_SPARC)
	unsigned long _flags;
#endif
#if defined(CONFIG_OF_PROMTREE)
	unsigned int unique_id;
#endif
#if defined(CONFIG_OF_KOBJ)
	struct bin_attribute attr;
#endif
};

---

	demo@123456789 {				/*节点名demo，规则：'节点名@地址;，'节点名'，'路径引用：节点名'*/
		compatible = "fs4412,demo";		/*节点属性compatible：匹配节点的字符串，规则"厂商,节点名"*/
		reg = <0x11111111 0x2 0x22222222 0x4>; 	/*通用属性：资源I/O地址，数组存储，2维：2列N行*/
		interrupts = <0 1 2>, <1 2 4>;	/*通用属性：<中断类型 中断号 中断标志>，数组存储，2维：3列N行*/
		item1 = "a1","b2","c3";		/*自定义属性：传递一个字符串常量首地址*/
		item2,flag;			/*自定义属性：不传递内容，可能是开关或标志*/
	};

	struct device_node *node = NULL;
	struct property      *pp = NULL;
	unsigned long      *preg = NULL;
	unsigned long      *pint = NULL;
	unsigned char      *pstr = NULL;

    node = of_find_node_by_path("/demo@123456789");
    if (!IS_ENABLED(CONFIG_OF) || !node){
		printk(KERN_ERR "of find node fail. \n");
		return -EINVAL;
	}

    pp = of_find_property(node, "reg", NULL);
    printk(KERN_INFO"%s: %x\n", pp->name, pp->length);
    preg = pp->value;
    for(index = 0; index < (pp->length/sizeof(unsigned long)); index++){
        printk(KERN_INFO"[%d]: %lx\n", index, be32_to_cpu(preg[index]));
    }

	pp = of_find_property(node, "interrupts", NULL);
	if (!pp){
		printk(KERN_ERR"Not find interrupts\n");
	}else{
		printk(KERN_INFO"%s: %x\n", pp->name, pp->length);
		pint = pp->value;
		for(index = 0; index < (pp->length/sizeof(unsigned long)); index++){
			printk(KERN_INFO"[%d]: %lx\n", index, be32_to_cpu(pint[index]));
		}
	}