Re: [PATCH] arm64: dts: qcom: sdm845-lg: Enable NFC

[Paul Sajna]

On 2026-09-03 1:10 a.m., Konrad Dybcio wrote:
> On 9/3/26 4:03 AM, Paul Sajna wrote:
> > Add the i2c and tlmm nodes to support the NXP PN547 NFC chip
> >
> > Downstream dtsi for reference:
> > https://github.com/LineageOS/android_kernel_lge_sdm845/blob/lineage-22.2/arch/arm64/boot/dts/lge/sdm845-judy/sdm845-judyln_lao_com/sdm845-judyln_lao_com-nfc.dtsi
> >
> > Signed-off-by: Paul Sajna <sajattack@xxxxxxxxxxxxxxxx>
> > ---
>
> [...]
>
> > +	nfc_default: nfc-default-state {
> > +		pins = "gpio12", "gpio62", "gpio63";
> > +		function = "gpio";
> > +		drive-strength = <6>;
> > +		bias-pull-up;
>
> active-high pins and pull-ups don't really go well together, please
> verify that
>
> Konrad

Downstream decompile sez

nfc {

				nfc_int_active {
					phandle = <0x46a>;

					config {
						pins = "gpio63";
						drive-strength = <0x02>;
						bias-pull-up;
					};

					mux {
						pins = "gpio63";
						function = "gpio";
					};
				};

				nfc_enable_suspend {
					phandle = <0x46d>;

					config {
						pins = "gpio12", "gpio62", "gpio116";
						bias-disable;
						drive-strength = <0x02>;
					};

					mux {
						pins = "gpio12", "gpio62", "gpio116";
						function = "gpio";
					};
				};

				nfc_enable_active {
					phandle = <0x46c>;

					config {
						pins = "gpio12", "gpio62", "gpio116";
						drive-strength = <0x02>;
						bias-pull-up;
					};

					mux {
						pins = "gpio12", "gpio62", "gpio116";
						function = "gpio";
					};
				};

				nfc_int_suspend {
					phandle = <0x46b>;

					config {
						pins = "gpio63";
						drive-strength = <0x02>;
						bias-pull-up;
					};

					mux {
						pins = "gpio63";
						function = "gpio";
					};
				};
			};



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