[PATCH] ARM: dts: exynos/i9100: Unconditionally enable LDO12

[PATCH] ARM: dts: exynos/i9100: Unconditionally enable LDO12

[Paul Cercueil]

The kernel hangs for a good 12 seconds without any info being printed to
dmesg, very early in the boot process, if this regulator is not enabled.

Force-enable it to work around this issue, until we know more about the
underlying problem.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Fixes: 8620cc2f99b7 ("ARM: dts: exynos: Add devicetree file for the Galaxy S2")
Cc: <stable@vger.kernel.org> # v5.8+
---
 arch/arm/boot/dts/exynos4210-i9100.dts | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/arm/boot/dts/exynos4210-i9100.dts b/arch/arm/boot/dts/exynos4210-i9100.dts
index a9ec1f6c1dea..a076a1dfe41f 100644
--- a/arch/arm/boot/dts/exynos4210-i9100.dts
+++ b/arch/arm/boot/dts/exynos4210-i9100.dts
@@ -527,6 +527,14 @@ vtcam_reg: LDO12 {
 				regulator-name = "VT_CAM_1.8V";
 				regulator-min-microvolt = <1800000>;
 				regulator-max-microvolt = <1800000>;
+
+				/*
+				 * Force-enable this regulator; otherwise the
+				 * kernel hangs very early in the boot process
+				 * for about 12 seconds, without apparent
+				 * reason.
+				 */
+				regulator-always-on;
 			};
 
 			vcclcd_reg: LDO13 {
-- 
2.40.1

Re: [PATCH] ARM: dts: exynos/i9100: Unconditionally enable LDO12

[Krzysztof Kozlowski]

On 08/08/2023 13:03, Paul Cercueil wrote:
> The kernel hangs for a good 12 seconds without any info being printed to
> dmesg, very early in the boot process, if this regulator is not enabled.
> 
> Force-enable it to work around this issue, until we know more about the
> underlying problem.
> 
> Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> Fixes: 8620cc2f99b7 ("ARM: dts: exynos: Add devicetree file for the Galaxy S2")
> Cc: <stable@vger.kernel.org> # v5.8+
> ---
>  arch/arm/boot/dts/exynos4210-i9100.dts | 8 ++++++++

The path changed long time ago. Really, please do not work on some
outdated pmOS or whatever downstream drivers.

Best regards,
Krzysztof

Re: [PATCH] ARM: dts: exynos/i9100: Unconditionally enable LDO12

[Paul Cercueil]

Le jeudi 10 août 2023 à 08:21 +0200, Krzysztof Kozlowski a écrit :
> On 08/08/2023 13:03, Paul Cercueil wrote:
> > The kernel hangs for a good 12 seconds without any info being
> > printed to
> > dmesg, very early in the boot process, if this regulator is not
> > enabled.
> > 
> > Force-enable it to work around this issue, until we know more about
> > the
> > underlying problem.
> > 
> > Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> > Fixes: 8620cc2f99b7 ("ARM: dts: exynos: Add devicetree file for the
> > Galaxy S2")
> > Cc: <stable@vger.kernel.org> # v5.8+
> > ---
> >  arch/arm/boot/dts/exynos4210-i9100.dts | 8 ++++++++
> 
> The path changed long time ago. Really, please do not work on some
> outdated pmOS or whatever downstream drivers.

That was on v6.4.2 yes. I simply forgot to rebase on the latest RC,
sorry about that.

I'll send a V2, and I now have some more patches touching that file
that I can bundle with.

-Paul