Re: [RFC PATCH 0/2] Add a generic virtual thermal sensor

[Daniel Lezcano]

Hi Alexandre,

thanks for the proposal.

On 19/08/2021 14:32, Alexandre Bailon wrote:
> This series add a virtual thermal sensor that uses the hardware thermal sensors,
> aggregate them to return a temperature.
> 
> My first aptempt was to do the aggregation in the thermal zone but it was not
> that easy to do, and, there were some case that would have been conflictual
> such as setting differents trip for a regular zone and a multisensor zone.
> 
> Instead, I made a virtual thermal sensor that could registered in a thermal
> zone, and have its own properties.
> It could be added in the device tree, with the list of sensors to aggregate,
> and the type of aggregation to be done.
> 
> As example:
>   soc_max_sensor: soc_max_sensor {
>     compatible = "generic,thermal-aggregator";
>     #thermal-sensor-cells = <1>;
>     type = "max";
>     thermal-sensors = <&lvts 0>, <&lvts 1>, <&lvts 2>, <&lvts 3>,
>           <&lvts 4>, <&lvts 5>, <&lvts 6>, <&lvts 7>,
>           <&lvts 8>, <&lvts 9>, <&lvts 10>, <&lvts 11>,
>           <&lvts 12>, <&lvts 13>, <&lvts 14>, <&lvts 15>,
>           <&lvts 16>;
>   };
> 
> The current series build and work but it would require to be completed
> aswell a lot of cleanup.
> Before working on it, I would like to get some feedback and I know if that
> would an acceptable solution and continue that way.

Yes, I think it is going to the right direction.

IMO, we can get rid of the thermal_of changes. From a design PoV, the
patch itself should be the virtual thermal driver without any changes in
the core code, including thermal_of.

I have some comments on patch 2/2


> Follows the following discussion:
> https://patchwork.kernel.org/project/linux-mediatek/patch/20210617114707.10618-3-ben.tseng@xxxxxxxxxxxx/
> 
> Alexandre Bailon (2):
>   thermal: provide a way to get thermal sensor from a device tree node
>   thermal: add a virtual sensor to aggregate temperatures
> 
>  drivers/thermal/Kconfig              |   8 ++
>  drivers/thermal/Makefile             |   1 +
>  drivers/thermal/thermal_aggregator.c | 134 +++++++++++++++++++++++++++
>  drivers/thermal/thermal_of.c         |  43 +++++++++
>  include/linux/thermal.h              |  12 +++
>  5 files changed, 198 insertions(+)
>  create mode 100644 drivers/thermal/thermal_aggregator.c
> 


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