Re: [PATCH 2/3] dt-bindings: gpio: Convert UniPhier GPIO to json-schema

From: Rob Herring <robh@kernel.org>
To: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: devicetree@vger.kernel.org, Frank Rowand <frowand.list@gmail.com>,
	Masahiro Yamada <yamada.masahiro@socionext.com>,
	Bartosz Golaszewski <bgolaszewski@baylibre.com>,
	"David S. Miller" <davem@davemloft.net>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Jonathan Cameron <Jonathan.Cameron@huawei.com>,
	Linus Walleij <linus.walleij@linaro.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Mauro Carvalho Chehab <mchehab+samsung@kernel.org>,
	linux-arm-kernel@lists.infradead.org, linux-gpio@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/3] dt-bindings: gpio: Convert UniPhier GPIO to json-schema
Date: Fri, 21 Feb 2020 09:32:15 -0600	[thread overview]
Message-ID: <20200221153215.GA9815@bogus> (raw)
In-Reply-To: <20200221021002.18795-2-yamada.masahiro@socionext.com>

On Fri, 21 Feb 2020 11:10:01 +0900, Masahiro Yamada wrote:
> Convert the UniPhier GPIO controller binding to DT schema format.
> 
> I omitted the 'gpio-ranges' property because it is defined in the
> dt-schema project (/schemas/gpio/gpio.yaml).
> 
> As of writing, the 'gpio-ranges-group-names' is not defined in that
> file despite it is a common property described in
> Documentation/devicetree/bindings/gpio/gpio.txt
> So, I defined it in this schema.
> 
> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
> ---
> 
> I have a question about the range about 'ngpio'.
> 
>   ngpios:
>     minimum: 0
>     maximum: 512
> 
> The 'ngpio' property is already defined as 'uint32' in the dt-schema tool:
> https://github.com/robherring/dt-schema/blob/master/schemas/gpio/gpio.yaml#L20
> 
> 'uint32' is unsigned, so 'minimum: 0' looks too obvious.
> 
> I cannot omit the minimum because minimum and maximum depend on each other.
> I just put a sensible number, 512, in maximum.
> 
> If this range is entirely unneeded, I will delete it.

This property is generally for when you can have some number less 
than a maximum number implied by the compatible string. 

If there is really no max (e.g. 2^32 - 1 is valid), then just do 
'ngpios: true'

> 
> 
>  .../bindings/gpio/gpio-uniphier.txt           | 51 -----------
>  .../gpio/socionext,uniphier-gpio.yaml         | 89 +++++++++++++++++++
>  MAINTAINERS                                   |  2 +-
>  3 files changed, 90 insertions(+), 52 deletions(-)
>  delete mode 100644 Documentation/devicetree/bindings/gpio/gpio-uniphier.txt
>  create mode 100644 Documentation/devicetree/bindings/gpio/socionext,uniphier-gpio.yaml
> 

My bot found errors running 'make dt_binding_check' on your patch:

Documentation/devicetree/bindings/display/simple-framebuffer.example.dts:21.16-37.11: Warning (chosen_node_is_root): /example-0/chosen: chosen node must be at root node
Error: Documentation/devicetree/bindings/gpio/socionext,uniphier-gpio.example.dts:38.34-35 syntax error
FATAL ERROR: Unable to parse input tree
scripts/Makefile.lib:300: recipe for target 'Documentation/devicetree/bindings/gpio/socionext,uniphier-gpio.example.dt.yaml' failed
make[1]: *** [Documentation/devicetree/bindings/gpio/socionext,uniphier-gpio.example.dt.yaml] Error 1
Makefile:1263: recipe for target 'dt_binding_check' failed
make: *** [dt_binding_check] Error 2

See https://patchwork.ozlabs.org/patch/1241747
Please check and re-submit.