Re: [PATCH 4/4] arm64: dts: qcom: qcm6490-fairphone-fp5: Add PM7325 thermals

[Konrad Dybcio]

On 10/14/23 19:52, Luca Weiss wrote:
> On Samstag, 14. Oktober 2023 01:13:29 CEST Konrad Dybcio wrote:
> > On 13.10.2023 10:09, Luca Weiss wrote:
> > > Configure the thermals for the QUIET_THERM, CAM_FLASH_THERM, MSM_THERM
> > > and RFC_CAM_THERM thermistors connected to PM7325.
> > >
> > > With this PMIC the software communication to the ADC is going through
> > > PMK7325 (= PMK8350).
> > >
> > > Signed-off-by: Luca Weiss <luca.weiss@xxxxxxxxxxxxx>
> > > ---
> > >
> > >   arch/arm64/boot/dts/qcom/qcm6490-fairphone-fp5.dts | 117
> > >   +++++++++++++++++++++ 1 file changed, 117 insertions(+)
> > >
> > > diff --git a/arch/arm64/boot/dts/qcom/qcm6490-fairphone-fp5.dts
> > > b/arch/arm64/boot/dts/qcom/qcm6490-fairphone-fp5.dts index
> > > 2c01f799a6b2..d0b1e4e507ff 100644
> > > --- a/arch/arm64/boot/dts/qcom/qcm6490-fairphone-fp5.dts
> > > +++ b/arch/arm64/boot/dts/qcom/qcm6490-fairphone-fp5.dts
> > > @@ -9,6 +9,7 @@
> > >
> > >   #define PM7250B_SID 8
> > >   #define PM7250B_SID1 9
> > >
> > > +#include <dt-bindings/iio/qcom,spmi-adc7-pm7325.h>
> > >
> > >   #include <dt-bindings/iio/qcom,spmi-adc7-pmk8350.h>
> > >   #include <dt-bindings/leds/common.h>
> > >   #include <dt-bindings/pinctrl/qcom,pmic-gpio.h>
> > >
> > > @@ -137,6 +138,20 @@ afvdd_2p8: regulator-afvdd-2p8 {
> > >
> > >   	};
> > >   	
> > >   	thermal-zones {
> > >
> > > +		camera-thermal {
> > > +			polling-delay-passive = <0>;
> > > +			polling-delay = <0>;
> > > +			thermal-sensors = <&pmk8350_adc_tm 2>;
> > > +
> > > +			trips {
> > > +				active-config0 {
> > > +					temperature = <125000>;
> >
> > are
> >
> > > +		rear-cam-thermal {
> > >
> > > +					temperature = <125000>;
> >
> > you
> >
> > > +		sdm-skin-thermal {
> > >
> > > +					temperature = <125000>;
> >
> > sure
> >
> > about these temps?
>
> (email from my other address, quicker right now)
>
> Well yes and no.
>
> Yes as in those are the temps specified in downstream dtb.
> No as in I'm 99% sure there's user space with definitely lower threshold that
> actually does something in response to the temps.
>
> I didn't look too much into this but does the kernel even do something when it
> hits one of these trip points? I assume when there's a cooling device thing
> specified then it can actually tell the driver to do something, but without
> (and most drivers don't support this?) I'm assuming the kernel can't do much
> anyways?
>
> So e.g. when the temperature for the flash led is reached I'm assuming
> downstream (+Android) either dims the led or turns it off? But I'd have to dig
> quite a bit into the thermal setup there to check what it's really doing.
I think reaching "critical" shuts down the platform, unless something
registering the thermal zone explicitly overrides the behavior.

> But for now I think it's okay to put this current thermal config into dts and
> we'll improve it later when 1. I understand more and 2. maybe some useful
> drivers support the cooling bits?
Yeah it's better than nothing, but ultimately we should probably move
the values that userspace daemon operates on here in the dt..

Konrad