Re: [PATCH 4/5] arm64: dts: qcom: milos-fairphone-fp6: Enable Bluetooth

["Luca Weiss" <luca.weiss@fairphone.com>]

On Wed Jan 21, 2026 at 12:52 PM CET, Konrad Dybcio wrote:
> On 1/16/26 3:50 PM, Luca Weiss wrote:
>> Add the nodes to describe the WCN6755 chip with its PMU and Bluetooth
>> parts.
>> 
>> Thanks to Alexander Koskovich for helping with the bringup, adding
>> 'clocks' to the PMU node to make Bluetooth work.
>> 
>> Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
>> ---
>>  arch/arm64/boot/dts/qcom/milos-fairphone-fp6.dts | 174 +++++++++++++++++++++++
>>  1 file changed, 174 insertions(+)
>> 
>> diff --git a/arch/arm64/boot/dts/qcom/milos-fairphone-fp6.dts b/arch/arm64/boot/dts/qcom/milos-fairphone-fp6.dts
>> index 52895dd9e4fa..cbe1507b0aaa 100644
>> --- a/arch/arm64/boot/dts/qcom/milos-fairphone-fp6.dts
>> +++ b/arch/arm64/boot/dts/qcom/milos-fairphone-fp6.dts
>> @@ -24,6 +24,7 @@ / {
>>  
>>  	aliases {
>>  		serial0 = &uart5;
>> +		serial1 = &uart11;
>>  	};
>>  
>>  	gpio-keys {
>> @@ -215,6 +216,67 @@ trip1 {
>>  			};
>>  		};
>>  	};
>> +
>> +	wcn6750-pmu {
>> +		compatible = "qcom,wcn6750-pmu"; /* WCN6755 */
>
> I think a fallback compatible would be in order, if the data matches
> exactly

That'd give us these changes

milos.dtsi:

    -+                  compatible = "qcom,wcn6750-wifi";
    ++                  compatible = "qcom,wcn6755-wifi", "qcom,wcn6750-wifi";

milos-fairphone-fp6.dts:

    -+          compatible = "qcom,wcn6750-pmu"; /* WCN6755 */
    ++          compatible = "qcom,wcn6755-pmu", "qcom,wcn6750-pmu";

    -+          compatible = "qcom,wcn6750-bt"; /* WCN6755 */
    ++          compatible = "qcom,wcn6755-bt", "qcom,wcn6750-bt";

Plus 3 new patches for dt-bindings, with commit message something like

Document the WCN6755 WiFi using a fallback to WCN6750 since the two
chips seem to be completely pin and software compatible. In fact the
original downstream kernel just pretends the WCN6755 is a WCN6750.

Does this sound okay?

>
>> +	bluetooth_enable_default: bluetooth-enable-default-state {
>> +		pins = "gpio53";
>> +		function = "gpio";
>> +		output-low;
>> +		bias-disable;
>> +	};
>
> Not sure if we need to drive that pin.. perhaps a pull-down would
> suffice?

I'll give it a shot, this pinctrl is coming from downstream but perhaps
the downstream btpower.c driver is differing in behavior to the upstream
PMU driver.

Regards
Luca

>
> [...]
>
>> +	bluetooth {
>> +		compatible = "qcom,wcn6750-bt"; /* WCN6755 */
>
> Likewise
>
> Konrad