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Message-ID: <c5e94d12-4f52-2e75-3b45-735afa0e987b@collabora.com>
Date:   Thu, 21 Jul 2022 10:40:31 +0200
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Subject: Re: [PATCH v1 3/6] dt-bindings: mediatek,mt6779-keypad: add
 mediatek,double-keys
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To:     Mattijs Korpershoek <mkorpershoek@baylibre.com>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Dmitry Torokhov <dmitry.torokhov@gmail.com>,
        Matthias Brugger <matthias.bgg@gmail.com>
Cc:     linux-kernel@vger.kernel.org, linux-input@vger.kernel.org,
        Fabien Parent <parent.f@gmail.com>, devicetree@vger.kernel.org,
        linux-mediatek@lists.infradead.org,
        Fabien Parent <fparent@baylibre.com>,
        linux-arm-kernel@lists.infradead.org
References: <20220720-mt8183-keypad-v1-0-ef9fc29dbff4@baylibre.com>
 <20220720-mt8183-keypad-v1-3-ef9fc29dbff4@baylibre.com>
From:   AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>
In-Reply-To: <20220720-mt8183-keypad-v1-3-ef9fc29dbff4@baylibre.com>
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Precedence: bulk

Il 20/07/22 16:48, Mattijs Korpershoek ha scritto:
> MediaTek keypad has 2 modes of detecting key events:
> - single key: each (row, column) can detect one key
> - double key: each (row, column) is a group of 2 keys
> 
> Currently, only single key detection is supported (by default)
> Add an optional property, mediatek,double-keys to support double
> key detection.
> 
> Double key support exists to minimize cost, since it reduces the number
> of pins required for physical keys.
> 
> Signed-off-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
> 
> diff --git a/Documentation/devicetree/bindings/input/mediatek,mt6779-keypad.yaml b/Documentation/devicetree/bindings/input/mediatek,mt6779-keypad.yaml
> index ca8ae40a73f7..03c9555849e5 100644
> --- a/Documentation/devicetree/bindings/input/mediatek,mt6779-keypad.yaml
> +++ b/Documentation/devicetree/bindings/input/mediatek,mt6779-keypad.yaml
> @@ -49,6 +49,12 @@ properties:
>       maximum: 256
>       default: 16
>   
> +  mediatek,double-keys:
> +    description: |
> +      use double key matrix instead of single key
> +      when set, each (row,column) is a group that can detect 2 keys

We can make it shorter and (imo) easier to understand, like:

   mediatek,double-keys:

     description: Each (row, column) group has two keys

...also because, if we say that the group "can detect" two keys, it may be
creating a misunderstandment such as "if I press one key, it gives me two
different input events for two different keys.", which is something that
wouldn't make a lot of sense, would it? :-)

> +    type: boolean
> +
>   required:
>     - compatible
>     - reg