[PATCH v3 04/10] arm64: dts: qcom: sc8280xp-arcata: Fix top USB-C DP alt mode

From: Jérôme de Bretagne via B4 Relay

Date: Thu Jun 04 2026 - 12:28:09 EST


From: Jérôme de Bretagne <jerome.debretagne@xxxxxxxxx>

The top USB-C port (usb0) didn't switch to DP alt mode, as reusing the
same GPIO 101 as on the SC8280XP CRD or Lenovo ThinkPad X13s was not
working on the Surface Pro 9 5G.

Investigation [1] by Jens on the Windows Dev Kit (WDK2023), the other
sc8280xp-based "blackrock" model from Microsoft, found a reference
to GPIO 100 in the DSDT in addition to 101. Switching to GPIO 100
fixed the issue on blackrock, as it does on arcata to enable
external screen when using the left-side top USB-C port.

[1] https://lore.kernel.org/all/20250609-blackrock-usb0-mux-v1-1-7903c3b071e4@xxxxxxxxxxxxxxxxxxxxxx/

Cc: Jens Glathe <jens.glathe@xxxxxxxxxxxxxxxxxxxxxx>
Fixes: f6231a2eefd4 ("arm64: dts: qcom: sc8280xp: Add Microsoft Surface Pro 9 5G")
Reviewed-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxxxxxxxx>
Signed-off-by: Jérôme de Bretagne <jerome.debretagne@xxxxxxxxx>
---
arch/arm64/boot/dts/qcom/sc8280xp-microsoft-arcata.dts | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/sc8280xp-microsoft-arcata.dts b/arch/arm64/boot/dts/qcom/sc8280xp-microsoft-arcata.dts
index c3b143ed11c73b7c1bedc576c10af8db30effc36..9abb52e3763715c8f72f8c95c068fd0b32901a1d 100644
--- a/arch/arm64/boot/dts/qcom/sc8280xp-microsoft-arcata.dts
+++ b/arch/arm64/boot/dts/qcom/sc8280xp-microsoft-arcata.dts
@@ -270,7 +270,7 @@ map1 {
usb0-sbu-mux {
compatible = "pericom,pi3usb102", "gpio-sbu-mux";

- enable-gpios = <&tlmm 101 GPIO_ACTIVE_LOW>;
+ enable-gpios = <&tlmm 100 GPIO_ACTIVE_LOW>;
select-gpios = <&tlmm 164 GPIO_ACTIVE_HIGH>;

pinctrl-0 = <&usb0_sbu_default>;
@@ -1079,7 +1079,7 @@ tx-pins {

usb0_sbu_default: usb0-sbu-state {
oe-n-pins {
- pins = "gpio101";
+ pins = "gpio100";
function = "gpio";
bias-disable;
drive-strength = <16>;

--
2.47.3