Re: [PATCH 4/6] arm64: dts: qcom: kaanapali-mtp: Enable bluetooth and Wifi
From: Zijun Hu
Date: Tue Apr 07 2026 - 02:49:40 EST
On 4/1/2026 10:07 PM, Dmitry Baryshkov wrote:
>>>> 2) its driver does not parse and use the property 'swctrl-gpios', moreover, the
>>>> property have no user within upstream DT tree.
>>> There is no "driver" in the "DT bindings"
>>>
>> 'its driver' i mean here is the driver which drives the device which is generated
>> by this DT node 'qcom,wcn7850-pmu'.
>> source code of the driver is drivers/power/sequencing/pwrseq-qcom-wcn.c
> DT describes the hardware. The driver behaviour is not that relevant
> here.
agree with your opinion which is right (^^)
>
>>>> 3) the property is not mandatory based on binding spec.
>>> Which is expected, because on some platforms it might be not wired up
>>> and on the other platforms the pin to which it is wired to might be
>>> unknown (think about all the phones for which the community doesn't have
>>> schematics).
>>>
>> got your points and will explain mine at below 2) together.
>>
>>>> 4) upstream DT tree have had many such usages as mine which just set default pin
>>>> configuration and not specify 'swctrl-gpios' explicitly.
>>> I don't understand this part.
>>>
>> For DT node 'qcom,wcn7850-pmu' of products identified by the following dts file at least:
>>
>> wcn7850-pmu {
>> compatible = "qcom,wcn7850-pmu";
>>
>> pinctrl-names = "default"; // config SW_CTRL pin default settings, but
>> pinctrl-0 = ....; // this DT node does not specify property 'swctrl-gpios'.
>> ....
>> }
>>
>>
>> grep -l -r "qcom,wcn7850-pmu" arch/arm64/boot/dts/qcom/ | xargs grep -l -r "sw[_-]ctrl"
>> arch/arm64/boot/dts/qcom/sm8550-hdk.dts
>> arch/arm64/boot/dts/qcom/sm8650-qrd.dts
>> arch/arm64/boot/dts/qcom/sm8750-mtp.dts
>> arch/arm64/boot/dts/qcom/sm8650-ayaneo-pocket-s2.dts
>> arch/arm64/boot/dts/qcom/sm8550-qrd.dts
>> arch/arm64/boot/dts/qcom/sm8650-hdk.dts
> So, let's fix them too.
>
perhaps. also fix for kaanapali-mtp whose DT have gone into linux-next.
BTW, there may be other 'qcom,wcnxxxx-pmu' which have the same problem to fix besides
'qcom,wcn7850-pmu'.
>>>> 5) kaanapali-mtp is originally preinstalled with android OS which supports some
>>>> qualcomm specific feature which have not been supported by up-stream kernel.
>>>> so kaanapali-mtp H/W has some wired pins which is not used by up-stream
>>>> kernel sometimes
>>> Again, what does that have to do with the hardware description?
>> kaanapali-mtp hardware supports the feature pin SW_CTRL involved, but we can decide
>> not to enable the feature based on requirements.
>>
>> any advise about how to correct DTS to not enable the feature SW_CTRL involved ?
> You can enable or disable something in the driver. It doesn't change the
> way the chip is wired (that's what DT describes).
got it. thank you. (^^)