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# SPDX-License-Identifier: BSD-2-Clause
# Copyright 2018 Linaro Ltd.
%YAML 1.2
---
# All the top-level keys are standard json-schema keywords except for
# 'maintainers' and 'select'
# $id is a unique idenifier based on the filename
$id: http://devicetree.org/schemas/example-schema.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#
title: An example schema annotated with jsonschema details
maintainers:
- Rob Herring <robh@kernel.org>
description: |
A more detailed multi-line description of the binding.
Details about the hardware device and any links to datasheets can go here.
The end of the description is marked by indentation less than the first line
in the description.
select: false
# 'select' is a schema applied to a DT node to determine if this binding
# schema should be applied to the node. It is optional and by default the
# possible compatible strings are extracted and used to match.
properties:
# A dictionary of DT properties for this binding schema
compatible:
# More complicated schema can use oneOf (XOR), anyOf (OR), or allOf (AND)
# to handle different conditions.
# In this case, it's needed to handle a variable number of values as there
# isn't another way to express a constraint of the last string value.
# The boolean schema must be a list of schemas.
oneOf:
- items:
# items is a list of possible values for the property. The number of
# values is determined by the number of elements in the list.
# Order in lists is significant, order in dicts is not
# Must be one of the 1st enums followed by the 2nd enum
#
# Each element in items should be 'enum' or 'const'
- enum:
- vendor,soc4-ip
- vendor,soc3-ip
- vendor,soc2-ip
- enum:
- vendor,soc1-ip
# additionalItems being false is implied
# minItems/maxItems equal to 2 is implied
- items:
# 'const' is just a special case of an enum with a single possible value
- const: vendor,soc1-ip
reg:
# The description of each element defines the order and implicitly defines
# the number of reg entries
items:
- description: core registers
- description: aux registers
# minItems/maxItems equal to 2 is implied
reg-names:
# The core schema enforces this is a string array
items:
- const: core
- const: aux
clocks:
# Only a single entry, so just need to set the max number of items.
maxItems: 1
clock-names:
items:
- const: bus
interrupts:
# Either 1 or 2 interrupts can be present
minItems: 1
maxItems: 2
items:
- description: tx or combined interrupt
- description: rx interrupt
description: |
A variable number of interrupts warrants a description of what conditions
affect the number of interrupts. Otherwise, descriptions on standard
properties are not necessary.
interrupt-names:
# minItems must be specified here because the default would be 2
minItems: 1
items:
- const: "tx irq"
- const: "rx irq"
# Property names starting with '#' must be quoted
'#interrupt-cells':
# A simple case where the value must always be '2'.
# The core schema handles that this must be a single integer.
const: 2
interrupt-controller: {}
# The core checks this is a boolean, so just have to list it here to be
# valid for this binding.
clock-frequency:
# The type is set in the core schema. Per device schema only need to set
# constraints on the possible values.
minimum: 100
maximum: 400000
# The value that should be used if the property is not present
default: 200
foo-gpios:
maxItems: 1
description: A connection of the 'foo' gpio line.
vendor,int-property:
description: Vendor specific properties must have a description
type: integer # A type is also required
enum: [2, 4, 6, 8, 10]
vendor,bool-property:
description: Vendor specific properties must have a description
type: boolean
required:
- compatible
- reg
- interrupts
- interrupt-controller
examples:
- |
/{
compatible = "vendor,soc4-ip", "vendor,soc1-ip";
reg = <0x1000 0x80>,
<0x3000 0x80>;
reg-names = "core", "aux";
interrupts = <10>;
interrupt-controller;
};
|
