Re: [PATCH] dt-bindings: Another round of adding missing 'additionalProperties'

From: Jonathan Cameron <Jonathan.Cameron@Huawei.com>
To: Rob Herring <robh@kernel.org>
Cc: <devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
	"Thierry Reding" <thierry.reding@gmail.com>,
	Linus Walleij <linus.walleij@linaro.org>,
	Stephen Boyd <sboyd@kernel.org>, Shawn Guo <shawnguo@kernel.org>,
	Bjorn Andersson <bjorn.andersson@linaro.org>,
	"Baolin Wang" <baolin.wang7@gmail.com>,
	Guenter Roeck <linux@roeck-us.net>,
	Jonathan Cameron <jic23@kernel.org>,
	Mauro Carvalho Chehab <mchehab@kernel.org>,
	Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>,
	Lee Jones <lee.jones@linaro.org>,
	Ulf Hansson <ulf.hansson@linaro.org>,
	"David S. Miller" <davem@davemloft.net>,
	Bjorn Helgaas <bhelgaas@google.com>,
	"Vinod Koul" <vkoul@kernel.org>,
	Liam Girdwood <lgirdwood@gmail.com>,
	Mark Brown <broonie@kernel.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Daniel Lezcano <daniel.lezcano@linaro.org>,
	<linux-clk@vger.kernel.org>, <dri-devel@lists.freedesktop.org>,
	<linux-spi@vger.kernel.org>, <linux-gpio@vger.kernel.org>,
	<linux-hwmon@vger.kernel.org>, <linux-iio@vger.kernel.org>,
	<openipmi-developer@lists.sourceforge.net>,
	<linux-leds@vger.kernel.org>, <linux-media@vger.kernel.org>,
	<linux-rockchip@lists.infradead.org>,
	<linux-stm32@st-md-mailman.stormreply.com>,
	<linux-mips@vger.kernel.org>, <linux-mmc@vger.kernel.org>,
	<netdev@vger.kernel.org>, <linux-pci@vger.kernel.org>,
	<linux-pm@vger.kernel.org>, <linux-remoteproc@vger.kernel.org>,
	<linux-serial@vger.kernel.org>, <alsa-devel@alsa-project.org>,
	<linux-usb@vger.kernel.org>
Subject: Re: [PATCH] dt-bindings: Another round of adding missing 'additionalProperties'
Date: Mon, 5 Oct 2020 10:34:36 +0100	[thread overview]
Message-ID: <20201005093436.00004913@Huawei.com> (raw)
In-Reply-To: <20201002234143.3570746-1-robh@kernel.org>

On Fri, 2 Oct 2020 18:41:43 -0500
Rob Herring <robh@kernel.org> wrote:

> Another round of wack-a-mole. The json-schema default is additional
> unknown properties are allowed, but for DT all properties should be
> defined.
> 
> Cc: Thierry Reding <thierry.reding@gmail.com>
> Cc: Linus Walleij <linus.walleij@linaro.org>
> Cc: Stephen Boyd <sboyd@kernel.org>
> Cc: Shawn Guo <shawnguo@kernel.org>
> Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
> Cc: Baolin Wang <baolin.wang7@gmail.com>
> Cc: Guenter Roeck <linux@roeck-us.net>
> Cc: Jonathan Cameron <jic23@kernel.org>
> Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
> Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
> Cc: Lee Jones <lee.jones@linaro.org>
> Cc: Ulf Hansson <ulf.hansson@linaro.org>
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: Bjorn Helgaas <bhelgaas@google.com>
> Cc: Vinod Koul <vkoul@kernel.org>
> Cc: Liam Girdwood <lgirdwood@gmail.com>
> Cc: Mark Brown <broonie@kernel.org>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
> Cc: linux-clk@vger.kernel.org
> Cc: dri-devel@lists.freedesktop.org
> Cc: linux-spi@vger.kernel.org
> Cc: linux-gpio@vger.kernel.org
> Cc: linux-hwmon@vger.kernel.org
> Cc: linux-iio@vger.kernel.org
> Cc: openipmi-developer@lists.sourceforge.net
> Cc: linux-leds@vger.kernel.org
> Cc: linux-media@vger.kernel.org
> Cc: linux-rockchip@lists.infradead.org
> Cc: linux-stm32@st-md-mailman.stormreply.com
> Cc: linux-mips@vger.kernel.org
> Cc: linux-mmc@vger.kernel.org
> Cc: netdev@vger.kernel.org
> Cc: linux-pci@vger.kernel.org
> Cc: linux-pm@vger.kernel.org
> Cc: linux-remoteproc@vger.kernel.org
> Cc: linux-serial@vger.kernel.org
> Cc: alsa-devel@alsa-project.org
> Cc: linux-usb@vger.kernel.org
> Signed-off-by: Rob Herring <robh@kernel.org>
> ---

Hi Rob,

Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # for iio

However, one of these made me wonder if the binding was simply wrong...
(definitely highlights why we should have additionalProperties: false
where ever possible).

...

> diff --git a/Documentation/devicetree/bindings/iio/imu/invensense,icm42600.yaml b/Documentation/devicetree/bindings/iio/imu/invensense,icm42600.yaml
> index abd8d25e1136..4c1c083d0e92 100644
> --- a/Documentation/devicetree/bindings/iio/imu/invensense,icm42600.yaml
> +++ b/Documentation/devicetree/bindings/iio/imu/invensense,icm42600.yaml
> @@ -47,11 +47,17 @@ properties:
>    vddio-supply:
>      description: Regulator that provides power to the bus
>  
> +  spi-max-frequency: true
> +  spi-cpha: true
> +  spi-cpol: true

It isn't completely unheard of for a device to operate in multiple SPI modes, but
it does seem to be fairly unusual.  I took a look at the datasheet and at least
from the provided timing diagrams, these are both required in SPI mode.

http://invensense.tdk.com/wp-content/uploads/2020/09/DS-000292-ICM-42605-v1.5.pdf

That doesn't make the binding wrong as such, but we could be tighter in checking this!

I'll add this to my list to take a closer look at sometime soonish.

Thanks.

Jonathan

> +
>  required:
>    - compatible
>    - reg
>    - interrupts
>  
> +additionalProperties: false
> +
>  examples:
>    - |