Re: [PATCH] arm64: dts: allwinner: h6: add eMMC voltage property for Beelink GS1

[Clément Péron <peron.clem@xxxxxxxxx>]

Hi Maxime,

On Wed, 30 Sep 2020 at 12:27, Maxime Ripard <maxime@xxxxxxxxxx> wrote:
>
> Hi,
>
> On Mon, Sep 28, 2020 at 05:00:37PM +0200, Clément Péron wrote:
> > VQMMC supply is connected to BLDO2 which provides 1.8V.
> >
> > Let's reflect this in the device-tree.
>
> This commit log doesn't really explain what is going on though?
>
> > Fixes: 089bee8dd119 ("arm64: dts: allwinner: h6: Introduce Beelink GS1 board")
> > Signed-off-by: Clément Péron <peron.clem@xxxxxxxxx>
> > ---
> >  arch/arm64/boot/dts/allwinner/sun50i-h6-beelink-gs1.dts | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/arch/arm64/boot/dts/allwinner/sun50i-h6-beelink-gs1.dts b/arch/arm64/boot/dts/allwinner/sun50i-h6-beelink-gs1.dts
> > index 049c21718846..3f20d2c9bbbb 100644
> > --- a/arch/arm64/boot/dts/allwinner/sun50i-h6-beelink-gs1.dts
> > +++ b/arch/arm64/boot/dts/allwinner/sun50i-h6-beelink-gs1.dts
> > @@ -145,6 +145,7 @@ &mmc2 {
> >       vqmmc-supply = <&reg_bldo2>;
>
> The Device Tree already expresses that the vqmmc supply is connected to
> BLDO2 which provides 1.8V here (together with the reg_bldo2 node).
>
> >       non-removable;
> >       cap-mmc-hw-reset;
> > +     mmc-hs200-1_8v;
>
> Whereas this indicates that the eMMC supports the HS200 MMC mode at 1.8V

What about a comment like this:

Sunxi mmc driver can't distinguish at runtime what's the I/O voltage
for HS200 mode.
Add a property in the device-tree to notify mmc core about this configuration.


Regards,
Clement

>
> Maxime