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Diffstat (limited to 'sys/contrib/device-tree/Bindings/writing-schema.rst')
| -rw-r--r-- | sys/contrib/device-tree/Bindings/writing-schema.rst | 44 |
1 files changed, 41 insertions, 3 deletions
diff --git a/sys/contrib/device-tree/Bindings/writing-schema.rst b/sys/contrib/device-tree/Bindings/writing-schema.rst index 7e71cdd1d6de..470d1521fa17 100644 --- a/sys/contrib/device-tree/Bindings/writing-schema.rst +++ b/sys/contrib/device-tree/Bindings/writing-schema.rst @@ -43,6 +43,36 @@ description or device does, standards the device conforms to, and links to datasheets for more information. + The YAML format has several options for defining the formatting of the text + block. The options are controlled with indicator characters following the key + (e.g. "description: \|"). The minimum formatting needed for a block should be + used. The formatting controls can not only affect whether the YAML can be + parsed correctly, but are important when the text blocks are rendered to + another form. The options are as follows. + + The default without any indicators is flowed, plain scalar style where single + line breaks and leading whitespace are stripped. Paragraphs are delimited by + blank lines (i.e. double line break). This style cannot contain ": " in it as + it will be interpretted as a key. Any " #" sequence will be interpretted as + a comment. There's other restrictions on characters as well. Most + restrictions are on what the first character can be. + + The second style is folded which is indicated by ">" character. In addition + to maintaining line breaks on double line breaks, the folded style also + maintains leading whitespace beyond indentation of the first line. The line + breaks on indented lines are also maintained. + + The third style is literal which is indicated by "\|" character. The literal + style maintains all line breaks and whitespace (beyond indentation of the + first line). + + The above is not a complete description of YAML text blocks. More details on + multi-line YAML text blocks can be found online: + + https://yaml-multiline.info/ + + https://www.yaml.info/learn/quote.html + select Optional. A json-schema used to match nodes for applying the schema. By default, without 'select', nodes are matched against their possible @@ -87,9 +117,14 @@ additionalProperties / unevaluatedProperties should be allowed. * additionalProperties: true - Rare case, used for schemas implementing common set of properties. Such - schemas are supposed to be referenced by other schemas, which then use - 'unevaluatedProperties: false'. Typically bus or common-part schemas. + - Top-level part: + Rare case, used for schemas implementing common set of properties. Such + schemas are supposed to be referenced by other schemas, which then use + 'unevaluatedProperties: false'. Typically bus or common-part schemas. + - Nested node: + When listing only the expected compatible of the nested node and there + is an another schema matching that compatible which ends with one of + two above cases ('false'). examples Optional. A list of one or more DTS hunks implementing this binding only. @@ -136,6 +171,9 @@ Coding style Use YAML coding style (two-space indentation). For DTS examples in the schema, preferred is four-space indentation. +Place entries in 'properties' and 'required' sections in the same order, using +style from Documentation/devicetree/bindings/dts-coding-style.rst. + Testing ------- |