Re: [PATCH v3] arm64: dts: qcom: arduino-monza: add WLAN enable and rfkill GPIO

[Konrad Dybcio]

On 5/15/26 2:08 PM, Qian Zhang wrote:
> 
> 
> On 5/15/2026 6:51 PM, Konrad Dybcio wrote:
>> On 5/11/26 10:48 AM, Qian Zhang via B4 Relay wrote:
>>> From: Qian Zhang <qian.zhang@xxxxxxxxxxxxxxxx>
>>>
>>> The QCNFA765 M.2 PCIe WLAN module requires GPIO56 (wlan_en) to be
>>
>> But isn't that just the wlan-en pin that the power sequencing driver
>> takes?
>>
>> ref: drivers/power/sequencing/pwrseq-qcom-wcn.c
>>
>> Konrad
> Thanks for the review.
> It's not the same pin functionally, though they share the same name. There are two key differences:
> 
> 
> Different power topology: The pwrseq-qcom-wcn.c driver targets WLAN
> hips powered by an on-board PMU via the power sequencing framework. In our case (VENTUNO Q), the WLAN module has its own internal PMU, and wlan_en controls the power-on/off of that internal PMU — it is not part of the board-level power sequencing.

I don't believe what you said about the pwrseq driver is true.

> PCIe probe ordering: The WLAN module connects to the PCIe root complex through a PCIe bridge that does not currently support hotplug. If we were to use a similar node configuration as in pwrseq-qcom-wcn.c, there is no guarantee that the WLAN module would be powered on before the PCIe root complex probes, which would cause enumeration failure.

What do you mean by "*currently* does not support hotplug"? Does that
depend on some more code changes?

Konrad