Re: [PATCH 2/2] dt-bindings: display: bridge: sil,sii9022: Add data-lines

[Krzysztof Kozlowski <krzk@kernel.org>]

On 03/10/2024 13:56, Wadim Egorov wrote:
> 
> 
> Am 03.10.24 um 12:03 schrieb Krzysztof Kozlowski:
>> On 03/10/2024 10:20, Wadim Egorov wrote:
>>> The SI9022 HDMI transmitter can be configured with 16, 18, or 24 input
>>> data lines. This commit introduces the data-lines property to the input
>>
>> lines? lanes? What are lines? like pins?
> 
> Yes, "lines" in this context refers to the number of pins used for the 
> input pixel data bus, which can support 16, 18, or 24-bit wide data 
> buses. These are parallel data lines (or pins) that carry uncompressed 
> digital video to the HDMI transmitter.
> 
>>
>>> endpoint, specifying the number of parallel RGB input pins connected
>>> to the transmitter.
>>>
>>> Signed-off-by: Wadim Egorov <w.egorov@phytec.de>
>>> ---
>>>   .../bindings/display/bridge/sil,sii9022.yaml        | 13 ++++++++++++-
>>>   1 file changed, 12 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/Documentation/devicetree/bindings/display/bridge/sil,sii9022.yaml b/Documentation/devicetree/bindings/display/bridge/sil,sii9022.yaml
>>> index 5a69547ad3d7..24306f8eb107 100644
>>> --- a/Documentation/devicetree/bindings/display/bridge/sil,sii9022.yaml
>>> +++ b/Documentation/devicetree/bindings/display/bridge/sil,sii9022.yaml
>>> @@ -81,9 +81,20 @@ properties:
>>>   
>>>       properties:
>>>         port@0:
>>> -        $ref: /schemas/graph.yaml#/properties/port
>>> +        unevaluatedProperties: false
>>> +        $ref: /schemas/graph.yaml#/$defs/port-base
>>>           description: Parallel RGB input port
>>>   
>>> +        properties:
>>> +          endpoint:
>>> +            $ref: /schemas/graph.yaml#/$defs/endpoint-base
>>> +            unevaluatedProperties: false
>>> +
>>> +            properties:
>>> +              data-lines:
>>
>> No, this will confuse everyone. Considering lack of description how
>> anyone would figure out what this means?
> 
> I guess from working with the hardware/reference manual and using this chip?
> 
> I don't think it is overly confusing, especially since the port is 
> already described as the "Parallel RGB input port" which clearly implies 
> the use of pins for data transmission.


I am surprised you do not find data-lanes and data-lines confusing. For
non-native English speakers this even might sound the same.

You used earlier pins and bits, so maybe it's the same as bus-width,
which is already used all over the bindings, including one of the bridges.

Anyway a generic property should go to video-interfaces.

> 
> I am open to other suggestions if you believe a different name would 
> improve clarity.
> 
> Btw, bridge/toshiba,tc358768.yaml, which performs a similar function, 
> also uses the term data-lines.

Then this has to go to common schema.

Oh, wait, video-interfaces already have it!

Best regards,
Krzysztof