Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <1dcdc4e3-520c-3f6d-9994-9eedc2211c6d@linaro.org>
Date:   Tue, 4 Oct 2022 16:57:11 +0200
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101
 Thunderbird/102.3.0
Subject: Re: [PATCH] dt-bindings: display: panel: use
 spi-peripheral-props.yaml
Content-Language: en-US
To:     Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc:     Thierry Reding <thierry.reding@gmail.com>,
        Sam Ravnborg <sam@ravnborg.org>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Linus Walleij <linus.walleij@linaro.org>,
        Markuss Broks <markuss.broks@gmail.com>,
        Daniel Mack <daniel@zonque.org>,
        Dillon Min <dillon.minfei@gmail.com>,
        dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20221004120907.72767-1-krzysztof.kozlowski@linaro.org>
 <YzwvDEKAzbqjSYjT@pendragon.ideasonboard.com>
 <64a355f2-e9a1-dcca-cb86-48805acae8d5@linaro.org>
 <YzwyT28hf7daYqa1@pendragon.ideasonboard.com>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <YzwyT28hf7daYqa1@pendragon.ideasonboard.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 04/10/2022 15:17, Laurent Pinchart wrote:
> Hi Krzysztof,
> 
> On Tue, Oct 04, 2022 at 03:10:29PM +0200, Krzysztof Kozlowski wrote:
>> On 04/10/2022 15:03, Laurent Pinchart wrote:
>>> On Tue, Oct 04, 2022 at 02:09:07PM +0200, Krzysztof Kozlowski wrote:
>>>> For devices connectable by SPI bus (e.g. already using
>>>> "spi-max-frequency" property), reference the "spi-peripheral-props.yaml"
>>>> schema to allow using all SPI device properties, even these which device
>>>> bindings author did not tried yet.
>>>
>>> Isn't this done implicitly by spi-controller.yaml ? SPI devices that are
>>> children of an SPI controller should match the patternProperties
>>> "^.*@[0-9a-f]+$" in that file, which has a $ref: spi-peripheral-props.yaml.
>>> Is there something I'm missing ?
>>
>> You are correct about one side of this - SPI controller bindings.
>> However these schemas here have clear: additional/unevaluatedProperties:
>> false, thus when they find DTS like:
>> panel@xxx {
>>   compatible = "one of these spi panels";
>>   ...
>>   spi-cs-high;
>>   spi-rx-delay-us = <50>;
>>   ... and some more from specific controllers
>> }
>>
>> you will get errors, because the panel schema does not allow them.
>>
>> The bindings were done (some time ago) in such way, that they require
>> that both SPI controller and SPI device reference spi-props.
> 
> You're absolutely right that additionalProperties needs to be replaced
> by unevaluatedProperties. Can the additions of $ref be dropped, or is
> that needed too ?

I just wrote above  - you need to reference the spi-props. Otherwise all
the SPI-related properties will be unknown/unevaluated.

Best regards,
Krzysztof