Re: [PATCH v3 1/2] dt-bindings: it6505: add properties to restrict output bandwidth

[Krzysztof Kozlowski]

On 07/10/2022 05:18, allen.chen@xxxxxxxxxx wrote:
> hi
> 
> -----Original Message-----
> From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> 
> Sent: Thursday, October 6, 2022 4:17 PM
> To: Allen Chen (陳柏宇) <allen.chen@xxxxxxxxxx>
> Cc: Jau-Chih Tseng (曾昭智) <Jau-Chih.Tseng@xxxxxxxxxx>; Kenneth Hung (洪家倫) <Kenneth.Hung@xxxxxxxxxx>; Hermes Wu (吳佳宏) <Hermes.Wu@xxxxxxxxxx>; Pin-yen Lin <treapking@xxxxxxxxxxxx>; Andrzej Hajda <andrzej.hajda@xxxxxxxxx>; Neil Armstrong <narmstrong@xxxxxxxxxxxx>; Robert Foss <robert.foss@xxxxxxxxxx>; Laurent Pinchart <Laurent.pinchart@xxxxxxxxxxxxxxxx>; Jonas Karlman <jonas@xxxxxxxxx>; Jernej Skrabec <jernej.skrabec@xxxxxxxxx>; David Airlie <airlied@xxxxxxxx>; Daniel Vetter <daniel@xxxxxxxx>; Rob Herring <robh+dt@xxxxxxxxxx>; Krzysztof Kozlowski <krzysztof.kozlowski+dt@xxxxxxxxxx>; open list:DRM DRIVERS <dri-devel@xxxxxxxxxxxxxxxxxxxxx>; open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS <devicetree@xxxxxxxxxxxxxxx>; open list <linux-kernel@xxxxxxxxxxxxxxx>
> Subject: Re: [PATCH v3 1/2] dt-bindings: it6505: add properties to restrict output bandwidth
> 
> On 06/10/2022 04:04, allen wrote:
>> From: allen chen <allen.chen@xxxxxxxxxx>
>>
>> Add properties to restrict dp output data-lanes and clock.
>>
>> Signed-off-by: Pin-Yen Lin <treapking@xxxxxxxxxxxx>
>> Signed-off-by: Allen Chen <allen.chen@xxxxxxxxxx>
>> ---
>>  .../bindings/display/bridge/ite,it6505.yaml          | 12 ++++++++++++
>>  1 file changed, 12 insertions(+)
>>
>> diff --git 
>> a/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml 
>> b/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
>> index 833d11b2303a..f5482a614d05 100644
>> --- a/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
>> +++ b/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
>> @@ -52,6 +52,16 @@ properties:
>>      maxItems: 1
>>      description: extcon specifier for the Power Delivery
>>  
>> +  ite,dp-output-data-lane-count:
>> +    description: restrict the dp output data-lanes with value of 1-4
> 
> Drop "with value of 1-4" because it is redundant, but instead explain what this property is about. "Restrict output" is not yet enough.
> Restrict the number? Or choose specific lanes? Why it cannot be data-lanes from video-interfaces?
> 
> ==> DP output bandwidth depends on data-lane-count, so the number of output data-lane-count will restrict output bandwidth.
> In this dt-binding we don't have output endpoint, so use another property name to configure.
> If need to use data-lanes, where can we put in this dt-binding?

I see you got review in v2 to rename it, but it still should be the same
property, if it has similar/same meaning. It can be put here. You just
need to define its type or reference other schema (e.g. video-interfaces
if applicable) which defines it.

Best regards,
Krzysztof