Re: [PATCH v4 2/5] dt-bindings: media: add mediatek ISP3.0 camsv

From: Krzysztof Kozlowski
Date: Fri Jan 12 2024 - 02:49:50 EST


On 12/01/2024 08:41, Laurent Pinchart wrote:
> On Fri, Jan 12, 2024 at 08:34:45AM +0100, Krzysztof Kozlowski wrote:
>> On 10/01/2024 15:14, Julien Stephan wrote:
>>> From: Phi-bang Nguyen <pnguyen@xxxxxxxxxxxx>
>>>
>>> This adds the bindings, for the ISP3.0 camsv module embedded in
>>> some Mediatek SoC, such as the mt8365
>>>
>>> Signed-off-by: Phi-bang Nguyen <pnguyen@xxxxxxxxxxxx>
>>> Signed-off-by: Julien Stephan <jstephan@xxxxxxxxxxxx>
>>> Link: https://lore.kernel.org/r/20230807094940.329165-4-jstephan@xxxxxxxxxxxx
>>> ---
>>> .../bindings/media/mediatek,mt8365-camsv.yaml | 109 ++++++++++++++++++
>>> MAINTAINERS | 1 +
>>> 2 files changed, 110 insertions(+)
>>> create mode 100644 Documentation/devicetree/bindings/media/mediatek,mt8365-camsv.yaml
>>>
>>> diff --git a/Documentation/devicetree/bindings/media/mediatek,mt8365-camsv.yaml b/Documentation/devicetree/bindings/media/mediatek,mt8365-camsv.yaml
>>> new file mode 100644
>>> index 000000000000..097b1ab6bc72
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/media/mediatek,mt8365-camsv.yaml
>>> @@ -0,0 +1,109 @@
>>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>>> +# Copyright (c) 2023 MediaTek, BayLibre
>>> +%YAML 1.2
>>> +---
>>> +$id: http://devicetree.org/schemas/media/mediatek,mt8365-camsv.yaml#
>>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>>> +
>>> +title: MediaTek CAMSV 3.0
>>> +
>>> +maintainers:
>>> + - Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
>>> + - Julien Stephan <jstephan@xxxxxxxxxxxx>
>>> + - Andy Hsieh <andy.hsieh@xxxxxxxxxxxx>
>>> +
>>> +description:
>>> + The CAMSV is a set of DMA engines connected to the SENINF CSI-2
>>> + receivers. The number of CAMSVs depend on the SoC model.
>>
>> DMA should not go to media, but to dma
>
> They're not generic DMA engines. The CAMSV is a video capture device
> that includes a DMA engine, much like pretty much all the other video
> capture devices.

OK, some more explanation would be useful in description.

>
>>> +
>>> +properties:
>>> + compatible:
>>> + const: mediatek,mt8365-camsv
>>> +
>>> + reg:
>>> + items:
>>> + - description: camsv base
>>> + - description: img0 base
>>> + - description: tg base
>>> +
>>> + interrupts:
>>> + maxItems: 1
>>> +
>>> + power-domains:
>>> + maxItems: 1
>>> +
>>> + clocks:
>>> + items:
>>> + - description: cam clock
>>> + - description: camtg clock
>>> + - description: camsv clock
>>> +
>>> + clock-names:
>>> + items:
>>> + - const: cam
>>> + - const: camtg
>>> + - const: camsv
>>> +
>>> + iommus:
>>> + maxItems: 1
>>> +
>>> + ports:
>>> + $ref: /schemas/graph.yaml#/properties/ports
>>> +
>>> + properties:
>>> + port@0:
>>> + $ref: /schemas/graph.yaml#/properties/port
>>> + description: connection point for camsv0
>>
>> This explains me nothing. What type of connection point? How does it fit
>> the pipeline going to the display?
>
> The description seems wrong, it should state
>
> description: Connection to the SENINF output
>
> or something similar.

I am still not sure whether DMA engine should be connected via graphs.

Best regards,
Krzysztof