Re: [PATCH] arm64: dts: qcom: sc8280xp: use refgen regulator for DSI

[Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>]

On 4/17/26 2:23 PM, Pengyu Luo wrote:
> On Sat, Feb 28, 2026 at 9:13 PM Dmitry Baryshkov
> <dmitry.baryshkov@oss.qualcomm.com> wrote:
>>
>> On Sat, Feb 28, 2026 at 08:54:30PM +0800, Pengyu Luo wrote:
>>> Use it for the DSI controllers, since DSI nodes have been added.
>>>
>>> Signed-off-by: Pengyu Luo <mitltlatltl@gmail.com>
>>> ---
>>> This patch depends on the below series:
>>> https://lore.kernel.org/linux-arm-msm/20260228101907.18043-1-mitltlatltl@gmail.com/
>>
>> Why was it not squashed into that series? I'd assume that DSI nodes are
>> incomplete and are working "by luck" without the refgen supplies.
>>
> 
> Today, I did a casual read. I found the register(0x8900000 + 0x80) to
> enable refgen is always 0 on windows. The refgen driver may be not
> compatible with sc8280xp or the DT configuration is wrong.

The Linux driver casts a software vote. Most newer SoCs should have
a separate hw line between the PHYs and the REFGEN regulator to take
care of it automatically.

Even if a little unnecessary, this won't hurt

I *think* base+0xc & BIT(3) should tell you whether the power is
actually flowing at a given moment

Konrad