[PATCH v2 2/7] drm/tilcdc: Add blue-and-red-crossed devicetree property

[Jyri Sarha]

On 08/30/16 15:46, Tomi Valkeinen wrote:
> 
> 
> On 26/08/16 20:44, Jyri Sarha wrote:
>> On 08/26/16 15:51, Rob Herring wrote:
>>>> --- a/Documentation/devicetree/bindings/display/tilcdc/tilcdc.txt
>>>>> +++ b/Documentation/devicetree/bindings/display/tilcdc/tilcdc.txt
>>>>> @@ -17,6 +17,8 @@ Optional properties:
>>>>>     the lcd controller.
>>>>>   - max-pixelclock: The maximum pixel clock that can be supported
>>>>>     by the lcd controller in KHz.
>>>>> + - blue-and-red-crossed: Boolean property, set this of blue and red wires
>>>>> +   for LCD_DATA are crossed for 24-bit RGB support (and 16-bit BGR mode). [1]
>>> Doesn't this need to be blue-and-red-straight for compatibility?
>>>
>>
>> There is no way to be backward compatible with all am3 based devices.
> 
> Hmm, I guess it would be possible to have three options:
> 
> - No property set: driver advertises RG16 and RG24. This is wrong, but
> that's what the current status is, right?
> - Property set to "default" or "straight" or whatever: driver says RG16
> and BG24
> - Property set to "crossed": driver says BG16 and RG24
> 

Yes, that would be backward compatible and probably the best approach.
As this way all applications would still run, even if the colours are
wrong (as they have always been).

I'll do that if no one suggests otherwise.

BR,
Jyri