Intro：
https://www.kernel.org/doc/Documentation/devicetree/usage-model.txt
Usage：
http://devicetree.org/Device_Tree_Usage
Open Firmware Device Tree or Device Tree , is a data structure and language for describing hardware. More specifically , it is a description of hardware that is reachable by an operating system so that the OS doesn't neet to hard code detiles of the machine.
Structurally the DT is a tree, or a acyclic graph with named nodes, and nodes may have an arbitrary number of named properties encapsulating arbitrary data. A mechanism also exists to create arbitrary links form one node to another outside of the natural tree structure.
acyclic
美: [ˌeɪ'saɪklɪk]
英: [ˌeɪ'saɪklɪk]
adj. 非周期的；非循环的；无环的；非环状的
网络 非轮生的；非周期性的；无回路的
arbitrary
美: ['ɑrbɪ.treri]
英: ['ɑː(r)bɪtrəri]
adj. 任意的；武断的；随心所欲的；专横的
网络 专断的；随意的；任意角度
encapsulate
美: [ɪn'kæpsjə.leɪt]
英: [ɪn'kæpsjʊleɪt]
v. 压缩；把…包于胶囊等中
网络 封装；包封；封入
mechanism
美: ['mekə.nɪzəm]
英: ['mekə.nɪz(ə)m]
n. 机制；机械装置；方法；机件
网络 机构；机理；机械论
conceptually
美: [kən'septʃʊəlɪ]
英: [kən'septʃʊəlɪ]
adv. 概念上地
网络 概念地；概念上而言；概念上的喜欢
binding
美: ['baɪndɪŋ]
英: ['baɪndɪŋ]
n. 捆绑；装帧；缀结；黏合
adj. 有束缚力的；缚[捆,绑]…的；黏合的；连结的
v. “bind”的现在分词
网络 固定器；通信绑定；没有绑定
wary
美: ['weri]
英: ['weəri]
adj. （对待人或事物时）小心的
网络 谨慎的；机警的；小心翼翼的
As much as possible , hardware is described using existing binings to maximize use of existing support code, but since property and nod enames are simple text string s, it is easy to extend existing bindings or create newones by defining new nodes and properties. By wary, however , of creating a new binding without first doing some homework about what already exists . There are currently two different , incompatible , bindings for i2c busses that came about because the new binding was created without first investigating how i2c devices were already being enumerated in existing systems;
1. History
The DT was
