Re: [PATCH 1/8] dt-bindings: embedded-controller: qcom,hamoa-crd-ec: Add qcom,tsens

From: Anvesh Jain P

Date: Fri Jul 31 2026 - 02:01:37 EST




On 7/30/2026 10:41 PM, Konrad Dybcio wrote:
> On 7/29/26 2:13 PM, Anvesh Jain P wrote:
>>
>>
>> On 7/29/2026 4:43 PM, Konrad Dybcio wrote:
>>> On 7/28/26 7:44 PM, Anvesh Jain P wrote:
>>>> Add the qcom,tsens property so Hamoa-based boards can list the tsens
>>>> providers, and how many leading sensor IDs on each, whose readings the
>>>> driver averages to compute the SoC junction temperature reported to
>>>> the EC for fan control.
>
> [...]
>
>>>> + qcom,tsens:
>>>> + description:
>>>> + List of tsens providers and, for each, the number of leading sensor
>>>> + IDs on that provider whose readings are averaged to compute the SoC
>>>> + junction temperature reported to the EC for fan control. Only
>>>> + applicable for Hamoa based devices.
>>>> + $ref: /schemas/types.yaml#/definitions/phandle-array
>>>> + minItems: 1
>>>> + maxItems: 2
>>>> + items:
>>>> + items:
>>>> + - description: phandle to a tsens thermal-sensor provider
>>>> + - description: number of leading sensor IDs on that provider to average
>>>
>>> Why don't we want to look at all of the TSENS sensors?
>>>
>>> Konrad
>>
>> Each tsens provider has more physical sensors (16) than the count used
>> here. The leading N we take exactly matches the number of sensors
>> already wired to board thermal-zones for other purposes (CPU clusters,
>> GPU, camera, etc.) on that provider — e.g. on hamoa, tsens2 has 11 such
>> zones and tsens3 has 15, matching qcom,tsens = <&tsens2 11>, <&tsens3
>> 15>;. The remaining sensor IDs aren't referenced by any thermal-zone on
>> this platform, so there's no per-purpose reading to include in the SoC
>> Tj average.
>
> What you said is true
>
> It also doesn't answer the question why that isn't the case
>
> Konrad

What I meant is, the driver looks up a thermal zone for each sensor id,
and skips the ones that don't have a zone in DT. Sensor ids past 11/15
on this board don't have a zone assigned, so there's nothing to read there.

--
Best Regards,
Anvesh