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

[Pengyu Luo]

On Fri, Apr 17, 2026 at 8:37 PM Konrad Dybcio
<konrad.dybcio@xxxxxxxxxxxxxxxx> wrote:
>
> On 4/17/26 2:23 PM, Pengyu Luo wrote:
> > On Sat, Feb 28, 2026 at 9:13 PM Dmitry Baryshkov
> > <dmitry.baryshkov@xxxxxxxxxxxxxxxx> 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@xxxxxxxxx>
> >>> ---
> >>> This patch depends on the below series:
> >>> https://lore.kernel.org/linux-arm-msm/20260228101907.18043-1-mitltlatltl@xxxxxxxxx/
> >>
> >> 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
>

I see. Thanks for your explanation!

Best wishes,
Pengyu

> Konrad