On Wed 18 Apr 15:29 PDT 2018, Rob Herring wrote: > The current DT binding documentation format of freeform text is painful > to write, review, validate and maintain. > > This is just an example of what a binding in the schema format looks > like. It's using jsonschema vocabulary in a YAML encoded document. Using > jsonschema gives us access to existing tooling. A YAML encoding gives us > something easy to edit. > > This example is just the tip of the iceberg, but it the part most > developers writing bindings will interact with. Backing all this up > are meta-schema (to validate the binding schemas), some DT core schema, > YAML encoded DT output with dtc, and a small number of python scripts to > run validation. The gory details including how to run end-to-end > validation can be found here: > > https://www.spinics.net/lists/devicetree-spec/msg00649.html > > Signed-off-by: Rob Herring <robh@xxxxxxxxxx> > --- > Cc list, > You all review and/or write lots of binding documents. I'd like some feedback > on the format. > I really like the idea of formalizing the binding document format and the ability of validating a dtb is really nice. > Thanks, > Rob > > .../devicetree/bindings/example-schema.yaml | 149 +++++++++++++++++++++ > 1 file changed, 149 insertions(+) > create mode 100644 Documentation/devicetree/bindings/example-schema.yaml > > diff --git a/Documentation/devicetree/bindings/example-schema.yaml b/Documentation/devicetree/bindings/example-schema.yaml [..] > + 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 I assume that a reg with variable number of entries would have "description" for all of them and then a minItems that matches the required ones and maxItems matching all of them? > + > + reg-names: > + # The core schema enforces this is a string array > + items: > + - const: core > + - const: aux I presume validation based on this should check that there's equal number of entries in reg-names as there where in reg. Should this relationship be described in the schema? [..] > + 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. For validation purposes this could be interrupts with interrupt-parents or a interrupts-extend, a fact that we probably don't want to duplicate in every definition? Perhaps we should just do like you did here and define the "interrupts" and then in the validation tool - where we need to encode the logic behind this anyways - we support the different variants. > + > + interrupt-names: > + # minItems must be specified here because the default would be 2 > + minItems: 1 As with reg-names, it would be good to have the validator warn if this is not the same number of items as entries in "interrupts". > + 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 If this is specified then interrupt-controller should also be given, or vise versa. How would we describe that? > + > + interrupt-controller: {} > + # The core checks this is a boolean, so just have to list it here to be > + # valid for this binding. > + Regards, Bjorn -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
