devicetree/bindings/example-schema.yaml

1 # SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
4 ---
5 # All the top-level keys are standard json-schema keywords except for
10 $id: http://devicetree.org/schemas/example-schema.yaml#
11 # $schema is the meta-schema this schema should be validated with.
12 $schema: http://devicetree.org/meta-schemas/core.yaml#
17   - Rob Herring <robh@kernel.org>
20   A more detailed multi-line description of the binding.
29   # 'select' is a schema applied to a DT node to determine if this binding
30   # schema should be applied to the node. It is optional and by default the
33   # In this case, a 'false' schema will never match.
36   # A dictionary of DT properties for this binding schema
38     # More complicated schema can use oneOf (XOR), anyOf (OR), or allOf (AND)
42     # The boolean schema must be a list of schemas.
44       - items:
51           - enum:
52               - vendor,soc4-ip
53               - vendor,soc3-ip
54               - vendor,soc2-ip
55           - const: vendor,soc1-ip
58       - items:
60           - const: vendor,soc1-ip
63     # The core schema already checks that reg values are numbers, so device
64     # specific schema don't need to do those checks.
68       - description: core registers
69       - description: aux registers
72   reg-names:
73     # The core schema enforces this (*-names) is a string array
75       - const: core
76       - const: aux
86   clock-names:
87     # For single-entry lists in clocks, resets etc., the xxx-names often do not
89     # just skip the xxx-names.
91       - const: bus
97       - description: tx or combined interrupt
98       - description: rx interrupt
106   interrupt-names:
110       - const: tx irq
111       - const: rx irq
114   '#interrupt-cells':
116     # The core schema handles that this must be a single integer.
119   interrupt-controller: true
123   clock-frequency:
124     # The type is set in the core schema. Per-device schema only need to set
131   foo-gpios:
135   # *-supply is always a single phandle, so nothing more to define.
136   foo-supply: true
138   # Vendor-specific properties
140   # Vendor-specific properties have slightly different schema requirements than
143   vendor,int-property:
144     description: Vendor-specific properties must have a description
148   vendor,bool-property:
149     description: Vendor-specific properties must have a description. Boolean
150       properties are one case where the json-schema 'type' keyword can be used
154   vendor,string-array-property:
155     description: Vendor-specific properties should reference a type in the
156       core schema.
157     $ref: /schemas/types.yaml#/definitions/string-array
159       - enum: [foo, bar]
160       - enum: [baz, boo]
162   vendor,property-in-standard-units-microvolt:
163     description: Vendor-specific properties having a standard unit suffix
167   vendor,int-array-variable-length-and-constrained-values:
170     $ref: /schemas/types.yaml#/definitions/uint32-array
177   child-node:
178     description: Child nodes are just another property from a json-schema
180     type: object  # DT nodes are json objects
184       vendor,a-child-node-property:
185         description: Child node properties have all the same schema
190       - vendor,a-child-node-property
194   # 'vendor,bool-property' is only allowed when 'vendor,string-array-property'
196   vendor,bool-property: [ 'vendor,string-array-property' ]
199   vendor,string-array-property: [ 'vendor,bool-property' ]
202   - compatible
203   - reg
204   - interrupts
205   - interrupt-controller
207 # if/then schema can be used to handle conditions on a property affecting
211 # For multiple 'if' schema, group them under an 'allOf'.
214 # the binding into separate schema documents.
216   - if:
220             const: vendor,soc2-ip
223         - foo-supply
227         foo-supply: false
228   # Altering schema depending on presence of properties is usually done by
230   - if:
232         - vendor,bool-property
235         vendor,int-property:
238 # Ideally, the schema should have this line otherwise any other properties
240 # 'pinctrl-*' which are added automatically by the tooling.
242 # This can't be used in cases where another schema is referenced
244 # If and only if another schema is referenced and arbitrary children nodes can
252   # Examples have a default #address-cells and #size-cells value of 1. This can
256   # Any includes used have to be explicitly included. Use 4-space indentation.
257   - |
259         compatible = "vendor,soc4-ip", "vendor,soc1-ip";
262         reg-names = "core", "aux";
264         interrupt-controller;