From dfc84c2c0866c329c903ce2a298a61dc5c398e9b Mon Sep 17 00:00:00 2001 From: Shuai Zhang Date: Tue, 24 Mar 2026 14:59:48 +0800 Subject: [PATCH] WORKAROUND: arm64: dts: qcom: hamoa-iot-evk: support Bluetooth over both USB and UART On Hamoa boards, a single M.2 slot may host either a UART-based or a USB-based Bluetooth device. As a result, the UART controller node is always present in DT, while the USB path is hot-pluggable. When Bluetooth operates over USB, the presence of the UART DT node still causes the hci_qca UART driver to probe. During probe or power sequencing, the driver may deassert BT_EN, cutting power to the shared Bluetooth device and disconnecting the USB interface. Model BT_EN as an always-on fixed regulator so it cannot be toggled by the UART probe. This prevents the UART driver from interfering with Bluetooth operation when the device is connected over USB. Signed-off-by: Shuai Zhang --- arch/arm64/boot/dts/qcom/hamoa-iot-evk.dts | 34 ++++++++++++++++------ 1 file changed, 25 insertions(+), 9 deletions(-) diff --git a/arch/arm64/boot/dts/qcom/hamoa-iot-evk.dts b/arch/arm64/boot/dts/qcom/hamoa-iot-evk.dts index 79be3d347f471..e24858d5fadcc 100644 --- a/arch/arm64/boot/dts/qcom/hamoa-iot-evk.dts +++ b/arch/arm64/boot/dts/qcom/hamoa-iot-evk.dts @@ -514,6 +514,23 @@ regulator-boot-on; }; + vreg_wcn_bt_en: regulator-wcn-bt-en { + compatible = "regulator-fixed"; + + regulator-name = "VREG_WCN_BT_EN"; + regulator-min-microvolt = <1800000>; + regulator-max-microvolt = <1800000>; + + gpio = <&tlmm 116 GPIO_ACTIVE_HIGH>; + enable-active-high; + + pinctrl-0 = <&wcn_bt_en>; + pinctrl-names = "default"; + + regulator-always-on; + regulator-boot-on; + }; + vreg_wwan: regulator-wwan { compatible = "regulator-fixed"; @@ -679,10 +696,9 @@ vddrfa1p2-supply = <&vreg_wcn_1p9>; vddrfa1p8-supply = <&vreg_wcn_1p9>; - bt-enable-gpios = <&tlmm 116 GPIO_ACTIVE_HIGH>; wlan-enable-gpios = <&tlmm 117 GPIO_ACTIVE_HIGH>; - pinctrl-0 = <&wcn_bt_en>, <&wcn_wlan_en>; + pinctrl-0 = <&wcn_wlan_en>; pinctrl-names = "default"; regulators { @@ -1518,13 +1534,13 @@ compatible = "qcom,wcn7850-bt"; max-speed = <3200000>; - vddaon-supply = <&vreg_pmu_aon_0p59>; - vddwlcx-supply = <&vreg_pmu_wlcx_0p8>; - vddwlmx-supply = <&vreg_pmu_wlmx_0p85>; - vddrfacmn-supply = <&vreg_pmu_rfa_cmn>; - vddrfa0p8-supply = <&vreg_pmu_rfa_0p8>; - vddrfa1p2-supply = <&vreg_pmu_rfa_1p2>; - vddrfa1p8-supply = <&vreg_pmu_rfa_1p8>; + vddrfacmn-supply = <&vreg_wcn_3p3>; + vddaon-supply = <&vreg_wcn_3p3>; + vddwlcx-supply = <&vreg_wcn_3p3>; + vddwlmx-supply = <&vreg_wcn_3p3>; + vddrfa0p8-supply = <&vreg_wcn_3p3>; + vddrfa1p2-supply = <&vreg_wcn_3p3>; + vddrfa1p8-supply = <&vreg_wcn_3p3>; }; };