Re: [PATCH v2 1/3] dt-bindings: display: panel: ilitek,ili9488: make the port optional

[Krzysztof Kozlowski <krzk@kernel.org>]

On 10/11/2026 13:00, Krzysztof Kozlowski wrote:
> On Mon, Nov 09, 2026 at 05:07:04PM +0100, Romain TISSERAND wrote:
>> The panel is a MIPI-DSI peripheral, a child node of its DSI host, and the
>> driver does not use a graph port. A port is only needed when the host
>> links its panel through the graph; other DSI hosts, such as the Allwinner
>> sun6i-a31-mipi-dsi one, link the child node and have no output port to
>> point at. The PinePhone panel is described that way on the same host,
>> without a port.
>>
>> Keep the port allowed (panel-common) but no longer required, as for other
>> DSI panels such as ilitek,ili9881c.
> 
> ilitek,ili7807s and a few others have the same and it is confusing. The
> port should be required when this is connected over SPI or I2C, but not
> for MIPI DSI. I think that for MIPI DSI port is meaningless so actually
> incorrect.
> 
> Why was it added in the first place?
> 

However won't all DRM drivers actually require panel? see b089c0a9b14c
and 169466d4e59c which removed fallback to the child node.

Best regards,
Krzysztof