Re: [PATCH 1/2] dt-bindings: drm/msm: Update bindings for MDP5

[Archit Taneja <architt@codeaurora.org>]

On 10/20/2015 11:47 PM, Rob Clark wrote:
> On Mon, Oct 19, 2015 at 1:49 AM, Archit Taneja <architt@codeaurora.org> wrote:
>>
>> On 10/18/2015 08:49 AM, Bjorn Andersson wrote:
>>>
>>> On Fri, Oct 16, 2015 at 5:06 AM, Archit Taneja <architt@codeaurora.org>
>>> wrote:
>>>>
>>>> MDP5 has a different compatible string (which causes checkpatch warnings
>>>> when we try to add MDP5 device nodes). It also has different list of
>>>> clocks.
>>>>
>>>> Update the bindings for MDP5.
>>>>
>>>> Signed-off-by: Archit Taneja <architt@codeaurora.org>
>>>> ---
>>>>    Documentation/devicetree/bindings/drm/msm/mdp.txt | 23
>>>> ++++++++++++++++-------
>>>>    1 file changed, 16 insertions(+), 7 deletions(-)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/drm/msm/mdp.txt
>>>> b/Documentation/devicetree/bindings/drm/msm/mdp.txt
>>>> index 1a0598e..e926daa 100644
>>>> --- a/Documentation/devicetree/bindings/drm/msm/mdp.txt
>>>> +++ b/Documentation/devicetree/bindings/drm/msm/mdp.txt
>>>> @@ -3,18 +3,27 @@ Qualcomm adreno/snapdragon display controller
>>>>    Required properties:
>>>>    - compatible:
>>>>      * "qcom,mdp" - mdp4
>>>> +  * "qcom,mdss_mdp" - mdp5
>>>
>>>
>>> Wouldn't it be better to name these "qcom,mdp4" and "qcom,mdp5" so
>>> that we don't have to rely on some magic detection mechanism to
>>> support future versions?
>>
>>
>> My guess is that compatibility string "mdss_mdp" came from the
>> downstream kernels. Chips having MDP4 were supported on downstream
>> kernels that preceded DT.
>>
>> Since we don't have any MDP DT upstream, I think we could go with the
>> string names you suggested. It might break things for people who might
>> try to use an old downstream dts file with a new kernel. But that
>> doesn't sound like the worst thing.
>
> it would break things for downstream 3.10/mdp5 dt files..  but what
> I'd suggest is to make the code look for both qcom,mdp5 and
> qcom,mdss_mdp but only document the former

That's a good idea. I'll update the patches to do that.

Archit

>
> BR,
> -R
>
>> Archit
>>
>>>
>>> Regards,
>>> Bjorn
>>>
>>
>> --
>> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
>> hosted by The Linux Foundation

-- 
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