Re: [PATCH] power: supply: core: return -EAGAIN on uninitialized read temp

[Krzysztof Kozlowski <krzk@kernel.org>]

On 04/07/2024 18:41, Daniel Lezcano wrote:
> On 04/07/2024 10:52, Neil Armstrong wrote:
>> If the thermal core tries to update the temperature from an
>> uninitialized power supply, it will swawn the following warning:
>> thermal thermal_zoneXX: failed to read out thermal zone (-19)
>>
>> But reading from an uninitialized power supply should not be
>> considered as a fatal error, but the thermal core expects
>> the -EAGAIN error to be returned in this particular case.
>>
>> So convert -ENODEV as -EAGAIN to express the fact that reading
>> temperature from an uninitialized power supply shouldn't be
>> a fatal error, but should indicate to the thermal zone it should
>> retry later.
>>
>> It notably removes such messages on Qualcomm platforms using the
>> qcom_battmgr driver spawning warnings until the aDSP firmware
>> gets up and the battery manager reports valid data.
> 
> Is it possible to have the aDSP firmware ready first ?

I don't think so. ADSP firmware is a file, so as every firmware it can
be loaded from rootfs, not initramfs (unlike this driver), or even missing.

Best regards,
Krzysztof