[PATCH 2/2] ARM: dts: da850: add a node for the LCD controller

Tomi Valkeinen
2016-10-17T07:33:58Z

On 17/10/16 10:12, Sekhar Nori wrote:
> On Monday 17 October 2016 11:26 AM, Tomi Valkeinen wrote:
>> On 15/10/16 20:42, Sekhar Nori wrote:
>>
>>>> diff --git a/arch/arm/boot/dts/da850.dtsi b/arch/arm/boot/dts/da850.dtsi
>>>> index f79e1b9..32908ae 100644
>>>> --- a/arch/arm/boot/dts/da850.dtsi
>>>> +++ b/arch/arm/boot/dts/da850.dtsi
>>>
>>>> @@ -399,6 +420,14 @@
>>>> <&edma0 0 1>;
>>>> dma-names = "tx", "rx";
>>>> };
>>>> +
>>>> + display: display at 213000 {
>>>> + compatible = "ti,am33xx-tilcdc", "ti,da850-tilcdc";
>>>
>>> This should instead be:
>>>
>>> compatible = "ti,da850-tilcdc", "ti,am33xx-tilcdc";
>>>
>>> as the closest match should appear first in the list.
>>
>> Actually I don't think that's correct. The LCDC on da850 is not
>> compatible with the LCDC on AM335x. I think it should be just
>> "ti,da850-tilcdc".
>
> So if "ti,am33xx-tilcdc" is used, the display wont work at all? If thats
> the case, I wonder how the patch passed testing. Bartosz?

AM3 has "version 2" of LCDC, whereas DA850 is v1. They are quite
similar, but different.

The driver gets the version number from LCDC's register, and acts based
on that, so afaik the compatible string doesn't really affect the
functionality (as long as it matches).

But even if it works with the current driver, I don't think
"ti,am33xx-tilcdc" and "ti,da850-tilcdc" are compatible in the HW level.

Tomi

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