Re: [PATCH 4/4] arm64: dts: qcom: sm7225-fairphone-fp4: Wire up PM6150L LCDB

["Luca Weiss" <luca.weiss@fairphone.com>]

On Fri Nov 13, 2026 at 9:16 AM CET, Luca Weiss wrote:
> Since Linux has gained LCDB support now, wire up the LCDB regulators so
> we can turn them off and on as desired.

Actually after some more testing with extra patches, it seems that on
FP4 the touchscreen stays dead after toggling the lcdb regulator, while
on FP3 it works perfectly fine.

So please ignore this specific patch for now, I will figure out what the
problem is and re-submit. All the other patches in the series are still
good to go in!

Regards
Luca

> Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
> ---
>  arch/arm64/boot/dts/qcom/sm7225-fairphone-fp4.dts | 26 ++++++++++++++---------
>  1 file changed, 16 insertions(+), 10 deletions(-)
>
> diff --git a/arch/arm64/boot/dts/qcom/sm7225-fairphone-fp4.dts b/arch/arm64/boot/dts/qcom/sm7225-fairphone-fp4.dts
> index 37aa272019cc..d592bede6a61 100644
> --- a/arch/arm64/boot/dts/qcom/sm7225-fairphone-fp4.dts
> +++ b/arch/arm64/boot/dts/qcom/sm7225-fairphone-fp4.dts
> @@ -72,14 +72,6 @@ key-volume-up {
>  		};
>  	};
>  
> -	/* Dummy regulator until PM6150L has LCDB VSP/VSN support */
> -	lcdb_dummy: regulator-lcdb-dummy {
> -		compatible = "regulator-fixed";
> -		regulator-name = "lcdb_dummy";
> -		regulator-min-microvolt = <5500000>;
> -		regulator-max-microvolt = <5500000>;
> -	};
> -
>  	reserved-memory {
>  		/*
>  		 * The rmtfs memory region in downstream is 'dynamically allocated'
> @@ -784,8 +776,8 @@ panel@0 {
>  		reset-gpios = <&pm6150l_gpios 9 GPIO_ACTIVE_LOW>;
>  
>  		vdd1-supply = <&vreg_l1e>;
> -		vsn-supply = <&lcdb_dummy>;
> -		vsp-supply = <&lcdb_dummy>;
> +		vsn-supply = <&pm6150l_lcdb_ncp>;
> +		vsp-supply = <&pm6150l_lcdb_ldo>;
>  
>  		port {
>  			panel_in: endpoint {
> @@ -925,6 +917,20 @@ pm6150l_adc_default: adc-default-state {
>  	};
>  };
>  
> +&pm6150l_lcdb {
> +	status = "okay";
> +};
> +
> +&pm6150l_lcdb_ldo {
> +	regulator-min-microvolt = <5500000>;
> +	regulator-max-microvolt = <5500000>;
> +};
> +
> +&pm6150l_lcdb_ncp {
> +	regulator-min-microvolt = <5500000>;
> +	regulator-max-microvolt = <5500000>;
> +};
> +
>  &pm6150l_wled {
>  	qcom,switching-freq = <800>;
>  	qcom,current-limit-microamp = <20000>;