From: Stephen Boyd <sboyd@kernel.org>
To: Rob Herring <robh@kernel.org>
Cc: devicetree-spec@vger.kernel.org, devicetree@vger.kernel.org,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Grant Likely <grant.likely@arm.com>,
Frank Rowand <frowand.list@gmail.com>,
Mark Rutland <mark.rutland@arm.com>,
Geert Uytterhoeven <geert+renesas@glider.be>,
Linus Walleij <linus.walleij@linaro.org>,
Thierry Reding <thierry.reding@gmail.com>,
Mark Brown <broonie@kernel.org>, Shawn Guo <shawnguo@kernel.org>,
Bjorn Andersson <bjorn.andersson@linaro.org>,
Arnd Bergmann <arnd@arndb.de>,
Jonathan Cameron <jic23@kernel.org>
Subject: Re: [RFC PATCH] dt-bindings: add a jsonschema binding example
Date: Fri, 20 Apr 2018 16:41:44 -0700 [thread overview]
Message-ID: <152426770474.46528.1592920281091105196@swboyd.mtv.corp.google.com> (raw)
In-Reply-To: <CAL_Jsq+1G61+E0wtVEkzann3Z=2Cr=2PkbDJ_OuaA5GysWZsXQ@mail.gmail.com>
Quoting Rob Herring (2018-04-20 11:15:04)
> On Fri, Apr 20, 2018 at 11:47 AM, Stephen Boyd <sboyd@kernel.org> wrote:
> > Quoting Rob Herring (2018-04-18 15:29:05)
> >> diff --git a/Documentation/devicetree/bindings/example-schema.yaml b/Documentation/devicetree/bindings/example-schema.yaml
> >> new file mode 100644
> >> index 000000000000..fe0a3bd1668e
> >> --- /dev/null
> >> +++ b/Documentation/devicetree/bindings/example-schema.yaml
> >> @@ -0,0 +1,149 @@
> >> +
> >> + 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.
> >
> > Can we get a concrete example here?
>
> select: true
>
> :) Which is apply to every node.
>
> A better one is from the memory node schema ('$nodename' gets added :
>
> select:
> required: ["$nodename"]
> properties:
> $nodename:
> oneOf:
> - pattern: "^memory@[0-9a-f]*"
> - const: "memory" # 'memory' only allowed for selecting
>
>
> I expect the vast majority of device bindings will not use select at
> all and rely on compatible string matching.
Thanks! I was looking to see how the select syntax would work and this
shows one example nicely. I suppose another way would be to show how a
compatible string would be matched through select, even though it's
redundant.
Is there a way we can enforce node names through the schema too? For
example to enforce that a clock controller is called 'clock-controller'
or a spi master is called 'spi'.
>
> >> +
> >> +properties:
> > [...]
> >> +
> >> + interrupts:
> >> + # Either 1 or 2 interrupts can be present
> >> + minItems: 1
> >> + maxItems: 2
> >> + items:
> >> + - description: tx or combined interrupt
> >> + - description: rx interrupt
> >> +
> >> + description: |
> >
> > The '|' is needed to make yaml happy?
>
> Yes, this is simply how you do literal text blocks in yaml.
>
> We don't really need for this one really, but for the top-level
> 'description' we do. The long term intent is 'description' would be
> written in sphinx/rst and can be extracted into the DT spec (for
> common bindings). Grant has experimented with that some.
Ok. That sounds cool. Then we could embed links to datasheets and SVGs
too.
>
> >> + 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: {}
> >
> > Does '{}' mean nothing to see here?
>
> Yes. It's just an empty schema that's always valid.
Could we include another schema to indicate that this is an interrupt
controller? I'm sort of asking for multi-schema inheritance.
>
> >> + 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
> >
> > Can the required or optional parts go under each property instead of
> > having a different section?
>
> No, because then it is not json-schema language.
>
> > Or does that make the schema parser
> > difficult to implement?
>
> Yes, because then we have to implement a schema parser.
:/
next prev parent reply other threads:[~2018-04-20 23:41 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-04-18 22:29 [RFC PATCH] dt-bindings: add a jsonschema binding example Rob Herring
2018-04-20 16:47 ` Stephen Boyd
2018-04-20 18:15 ` Rob Herring
2018-04-20 19:53 ` Frank Rowand
2018-04-20 23:41 ` Stephen Boyd [this message]
2018-04-21 1:34 ` Rob Herring
2018-04-23 14:01 ` Grant Likely
2018-04-23 14:38 ` Rob Herring
2018-04-23 14:49 ` Grant Likely
2018-04-20 16:59 ` Mark Brown
2018-04-20 18:47 ` Rob Herring
2018-04-20 21:00 ` Frank Rowand
2018-04-21 1:28 ` Rob Herring
2018-04-23 7:25 ` Geert Uytterhoeven
2018-04-23 14:47 ` Grant Likely
2018-04-23 16:49 ` Geert Uytterhoeven
2018-04-25 10:15 ` Grant Likely
2018-04-25 0:33 ` Frank Rowand
2018-11-14 19:39 ` jonsmirl
2018-11-15 23:42 ` Rob Herring
2018-11-16 1:34 ` jonsmirl
2018-04-20 21:47 ` Bjorn Andersson
2018-04-23 16:51 ` Rob Herring
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=152426770474.46528.1592920281091105196@swboyd.mtv.corp.google.com \
--to=sboyd@kernel.org \
--cc=arnd@arndb.de \
--cc=bjorn.andersson@linaro.org \
--cc=broonie@kernel.org \
--cc=devicetree-spec@vger.kernel.org \
--cc=devicetree@vger.kernel.org \
--cc=frowand.list@gmail.com \
--cc=geert+renesas@glider.be \
--cc=grant.likely@arm.com \
--cc=jic23@kernel.org \
--cc=linus.walleij@linaro.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=robh@kernel.org \
--cc=shawnguo@kernel.org \
--cc=thierry.reding@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).