Documentation/devicetree/writing-schema.rst

1 .. SPDX-License-Identifier: GPL-2.0
3 Writing DeviceTree Bindings in json-schema
6 Devicetree bindings are written using json-schema vocabulary. Schema files are
12 ---------------
14 Each schema doc is a structured json-schema which is defined by a set of
15 top-level properties. Generally, there is one binding defined per file. The
16 top-level json-schema properties used are:
19   A json-schema unique identifier string. The string must be a valid
29   Indicates the meta-schema the schema file adheres to.
39   Optional. A multi-line text block containing any detailed
41   or device does, standards the device conforms to, and links to datasheets for
45   Optional. A json-schema used to match nodes for applying the
55   A set of sub-schema defining all the DT properties for the
78 ---------------
81 binding. Each property contains a set of constraints using json-schema
98 The default for arrays in json-schema is they are variable sized and allow more
100 'maxItems', and 'additionalItems'. However, for DeviceTree Schemas, a fixed
106 is present. Single entries in schemas are fixed up to match this encoding.
109 -------
118     pip3 install git+https://github.com/devicetree-org/dt-schema.git@master
120 Several executables (dt-doc-validate, dt-mk-schema, dt-validate) will be
129   apt-get install libyaml-dev
133   dnf -y install libyaml-devel
138 The DT schema binding documents must be validated using the meta-schema (the
139 schema for the schema) to ensure they are both valid json-schema and valid
162     make dt_binding_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/trivial-devices.yaml
163     make dtbs_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/trivial-devices.yaml
166 json-schema Resources
167 ---------------------
170 `JSON-Schema Specifications <http://json-schema.org/>`_