Re: [PATCH v2 3/3] arm64: dts: qcom: hamoa-iot-evk: Describe the PCIe M.2 Key E connector

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [High] The power sequencing integration for the dynamically created Bluetooth serdev is fundamentally broken due to device matching and target name mismatches, leaving the Bluetooth hardware disabled in reset.
- [Medium] The omission of the `max-speed` property silently degrades the Bluetooth UART operating baud rate from 3.2 Mbps to 3.0 Mbps.
--

--- Patch [3]: [PATCH v2 3/3] arm64: dts: qcom: hamoa-iot-evk: Describe the PCIe M.2 Key E connector ---
commit aea933a1454bca4e47c0fbb1565df4f442ed9a02
Author: Wei Deng <wei.deng@oss.qualcomm.com>
arm64: dts: qcom: hamoa-iot-evk: Describe the PCIe M.2 Key E connector

This commit replaces the Hamoa IoT EVK's chip-specific wcn7850-pmu with a
generic pcie-m2-e-connector node. It removes the static bluetooth serdev
and relies on the pwrseq-pcie-m2 driver to dynamically create the device
and manage power sequencing.

> diff --git a/arch/arm64/boot/dts/qcom/hamoa-iot-evk.dts b/arch/arm64/boot/dts/qcom/hamoa-iot-evk.dts
> --- a/arch/arm64/boot/dts/qcom/hamoa-iot-evk.dts
> +++ b/arch/arm64/boot/dts/qcom/hamoa-iot-evk.dts

[ ... ]

> @@ -538,6 +512,58 @@ vreg_wwan: regulator-wwan {
>  		regulator-boot-on;
>  	};
>  
> +	wifi-bt-connector {
> +		compatible = "pcie-m2-e-connector";
> +		vpcie3v3-supply = <&vreg_wcn_3p3>;
> +
> +		w-disable1-gpios = <&tlmm 117 GPIO_ACTIVE_LOW>;
> +		w-disable2-gpios = <&tlmm 116 GPIO_ACTIVE_LOW>;

[Severity: High]
Will this leave the Bluetooth hardware disabled in reset?

Because the hci_qca driver currently fails to match the power sequencer
for the "uart" target, it appears it will never un-assert w-disable2-gpios.

Does the dynamic serdev creation properly handle matching the sequencer
target name for this Bluetooth variant, or will the device fail to probe?

> +
> +		pinctrl-0 = <&wcn_wlan_en>, <&wcn_bt_en>;
> +		pinctrl-names = "default";

[ ... ]

> @@ -1531,17 +1490,10 @@ wcn_usb_sw_n: wcn-usb-sw-n-state {
>  &uart14 {
>  	status = "okay";
>  
> -	bluetooth {
> -		compatible = "qcom,wcn7850-bt";
> -		max-speed = <3200000>;

[Severity: Medium]
Does the dynamic node creation restore this max-speed property?

Without it, the Bluetooth UART falls back to 3.0 Mbps instead of 3.2 Mbps.

This transition from an integer to a fractional clock divider increases
the risk of UART framing errors and slightly degrades throughput.

> -
> -		vddaon-supply = <&vreg_pmu_aon_0p59>;
> -		vddwlcx-supply = <&vreg_pmu_wlcx_0p8>;

[ ... ]

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260723-hamoa-m2-dts-v2-v2-0-82254ac101fb@oss.qualcomm.com?part=3