Re: [net-next PATCH v5 10/15] dt-bindings: net: ethernet-controller: Document support for LEDs node

From: Christian Marangi <ansuelsmth@gmail.com>
To: Andrew Lunn <andrew@lunn.ch>
Cc: Rob Herring <robh@kernel.org>,
	Florian Fainelli <f.fainelli@gmail.com>,
	Vladimir Oltean <olteanv@gmail.com>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Heiner Kallweit <hkallweit1@gmail.com>,
	Russell King <linux@armlinux.org.uk>,
	Gregory Clement <gregory.clement@bootlin.com>,
	Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>,
	Andy Gross <agross@kernel.org>,
	Bjorn Andersson <andersson@kernel.org>,
	Konrad Dybcio <konrad.dybcio@linaro.org>,
	Pavel Machek <pavel@ucw.cz>, Lee Jones <lee@kernel.org>,
	John Crispin <john@phrozen.org>,
	netdev@vger.kernel.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-arm-msm@vger.kernel.org, linux-leds@vger.kernel.org
Subject: Re: [net-next PATCH v5 10/15] dt-bindings: net: ethernet-controller: Document support for LEDs node
Date: Wed, 22 Mar 2023 00:39:48 +0100	[thread overview]
Message-ID: <641a4046.7b0a0220.44d4e.95d4@mx.google.com> (raw)
In-Reply-To: <38534a25-4bb3-4371-b80b-abfc259de781@lunn.ch>

On Wed, Mar 22, 2023 at 12:23:59AM +0100, Andrew Lunn wrote:
> > > Are specific ethernet controllers allowed to add their own properties in 
> > > led nodes? If so, this doesn't work. As-is, this allows any other 
> > > properties. You need 'unevaluatedProperties: false' here to prevent 
> > > that. But then no one can add properties. If you want to support that, 
> > > then you need this to be a separate schema that devices can optionally 
> > > include if they don't extend the properties, and then devices that 
> > > extend the binding would essentially have the above with:
> > > 
> > > $ref: /schemas/leds/common.yaml#
> > > unevaluatedProperties: false
> > > properties:
> > >   a-custom-device-prop: ...
> > > 
> > > 
> > > If you wanted to define both common ethernet LED properties and 
> > > device specific properties, then you'd need to replace leds/common.yaml 
> > > above  with the ethernet one.
> > > 
> > > This is all the same reasons the DSA/switch stuff and graph bindings are 
> > > structured the way they are.
> > > 
> > 
> > Hi Rob, thanks for the review/questions.
> > 
> > The idea of all of this is to keep leds node as standard as possible.
> > It was asked to add unevaluatedProperties: False but I didn't understood
> > it was needed also for the led nodes.
> > 
> > leds/common.yaml have additionalProperties set to true but I guess that
> > is not OK for the final schema and we need something more specific.
> > 
> > Looking at the common.yaml schema reg binding is missing so an
> > additional schema is needed.
> > 
> > Reg is needed for ethernet LEDs and PHY but I think we should also permit
> > to skip that if the device actually have just one LED. (if this wouldn't
> > complicate the implementation. Maybe some hints from Andrew about this
> > decision?)
> 
> I would make reg mandatory.
>

Ok will add a new schema and change the regex.

> We should not encourage additional properties, but i also think we
> cannot block it.
> 
> The problem we have is that there is absolutely no standardisation
> here. Vendors are free to do whatever they want, and they do. So i
> would not be too surprised if some vendor properties are needed
> eventually.
>

Think that will come later with defining a more specific schema. But I
honestly think most of the special implementation will be handled to the
driver internally and not with special binding in DT.

-- 
	Ansuel