Received-SPF: pass (google.com: domain of linux-kernel+bounces-139249-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45e3:2400::1 as permitted sender) client-ip=2604:1380:45e3:2400::1;
Date: Wed, 10 Apr 2024 14:15:24 -0500
From: Rob Herring <robh@kernel.org>
To: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: chunkuang.hu@kernel.org, krzysztof.kozlowski+dt@linaro.org,
	conor+dt@kernel.org, p.zabel@pengutronix.de, airlied@gmail.com,
	daniel@ffwll.ch, maarten.lankhorst@linux.intel.com,
	mripard@kernel.org, tzimmermann@suse.de, matthias.bgg@gmail.com,
	shawn.sung@mediatek.com, yu-chang.lee@mediatek.com,
	ck.hu@mediatek.com, jitao.shi@mediatek.com,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
	dri-devel@lists.freedesktop.org, linux-mediatek@lists.infradead.org,
	linux-arm-kernel@lists.infradead.org, wenst@chromium.org,
	kernel@collabora.com
Subject: Re: [PATCH v2 2/3] dt-bindings: arm: mediatek: mmsys: Add OF graph
 support for board path
Message-ID: <20240410191524.GA903053-robh@kernel.org>
References: <20240409120211.321153-1-angelogioacchino.delregno@collabora.com>
 <20240409120211.321153-3-angelogioacchino.delregno@collabora.com>
Precedence: bulk
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20240409120211.321153-3-angelogioacchino.delregno@collabora.com>

On Tue, Apr 09, 2024 at 02:02:10PM +0200, AngeloGioacchino Del Regno wrote:
> Document OF graph on MMSYS/VDOSYS: this supports up to three DDP paths
> per HW instance (so potentially up to six displays for multi-vdo SoCs).
> 
> The MMSYS or VDOSYS is always the first component in the DDP pipeline,
> so it only supports an output port with multiple endpoints - where each
> endpoint defines the starting point for one of the (currently three)
> possible hardware paths.
> 
> Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
> ---
>  .../bindings/arm/mediatek/mediatek,mmsys.yaml | 23 +++++++++++++++++++
>  1 file changed, 23 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/arm/mediatek/mediatek,mmsys.yaml b/Documentation/devicetree/bindings/arm/mediatek/mediatek,mmsys.yaml
> index b3c6888c1457..4e9acd966aa5 100644
> --- a/Documentation/devicetree/bindings/arm/mediatek/mediatek,mmsys.yaml
> +++ b/Documentation/devicetree/bindings/arm/mediatek/mediatek,mmsys.yaml
> @@ -93,6 +93,29 @@ properties:
>    '#reset-cells':
>      const: 1
>  
> +  port:
> +    $ref: /schemas/graph.yaml#/properties/port
> +    description:
> +      Output port node. This port connects the MMSYS/VDOSYS output to
> +      the first component of one display pipeline, for example one of
> +      the available OVL or RDMA blocks.
> +      Some MediaTek SoCs support up to three display outputs per MMSYS.

I'm have a hard time understanding this, but is it 3 outputs 
simultaneously or connect mmsys to 1 of 3. Generally it's multiple ports 
for the former and endpoints for the latter.

> +    properties:
> +      endpoint@0:
> +        $ref: /schemas/graph.yaml#/properties/endpoint
> +        description: Output to the primary display pipeline
> +
> +      endpoint@1:
> +        $ref: /schemas/graph.yaml#/properties/endpoint
> +        description: Output to the secondary display pipeline
> +
> +      endpoint@2:
> +        $ref: /schemas/graph.yaml#/properties/endpoint
> +        description: Output to the tertiary display pipeline
> +
> +    required:
> +      - endpoint@0
> +
>  required:
>    - compatible
>    - reg
> -- 
> 2.44.0
>