[PATCH 06/13] arm64: dts: mediatek: mt8188: Update VPPSYS node name and compatible

[Krzysztof Kozlowski]

On 10/09/2024 13:06, Fei Shao wrote:
> On Tue, Sep 10, 2024 at 3:19 PM Krzysztof Kozlowski <krzk at kernel.org> wrote:
>>
>> On 10/09/2024 07:12, Fei Shao wrote:
>>> On Mon, Sep 9, 2024 at 7:41 PM Krzysztof Kozlowski <krzk at kernel.org> wrote:
>>>>
>>>> On 09/09/2024 13:14, Fei Shao wrote:
>>>>> Use and add "syscon" in VPPSYS node names and compatible to fix errors
>>>>> from `make CHECK_DTBS=y mediatek/mt8188-evb.dtb`.
>>>>>
>>>>> Signed-off-by: Fei Shao <fshao at chromium.org>
>>>>> ---
>>>>>
>>>>>  arch/arm64/boot/dts/mediatek/mt8188.dtsi | 8 ++++----
>>>>>  1 file changed, 4 insertions(+), 4 deletions(-)
>>>>>
>>>>> diff --git a/arch/arm64/boot/dts/mediatek/mt8188.dtsi b/arch/arm64/boot/dts/mediatek/mt8188.dtsi
>>>>> index 2900d78b7ceb..14e51a11f688 100644
>>>>> --- a/arch/arm64/boot/dts/mediatek/mt8188.dtsi
>>>>> +++ b/arch/arm64/boot/dts/mediatek/mt8188.dtsi
>>>>> @@ -1799,8 +1799,8 @@ mfgcfg: clock-controller at 13fbf000 {
>>>>>                       #clock-cells = <1>;
>>>>>               };
>>>>>
>>>>> -             vppsys0: clock-controller at 14000000 {
>>>>> -                     compatible = "mediatek,mt8188-vppsys0";
>>>>> +             vppsys0: syscon at 14000000 {
>>>>> +                     compatible = "mediatek,mt8188-vppsys0", "syscon";
>>>>
>>>> If this was working before, it looks like this is not a syscon and
>>>> bindings need to be fixed.
>>>
>>> I guess it's because the binding was later updated in commit
>>> 26bcd8a53098 ("dt-bindings: arm: mediatek: mmsys: Add VPPSYS
>>> compatible for MT8188"), and the corresponding DT update was unnoticed
>>> at the time.
>>> If that makes sense then this should be a valid fix.
>>
>> Not necessarily. Why not fixing bindings? Prove that bindings are
>> correct, not DTS, first.
> 
> MediaTek's mmsys doesn't merely control clocks, it also provides
> display pipeline routing control and other misc control registers, so
> it's appropriate to categorize it as a system controller over a clock
> controller.
> As for vdosys and vppsys, they are likely variants or aliases of mmsys
> introduced in their newer SoCs.

Nothing like that was in the commit msg...

> 
> That description was updated in commit 1a680aa888d6 ("dt-bindings:
> mediatek: Update mmsys binding to reflect it is a system controller"),
> so I just assumed it's correct without thinking much...


Best regards,
Krzysztof