power capping values on dbus

[Zbyszek]

Hi everyone!

I would like to expose on dbus values like min and max power capping.
These values could be read from files provided by hwmon like:
   power[1-*]_cap_max,
   power[1-*]_cap_min
which are describe here:
https://www.kernel.org/doc/Documentation/hwmon/sysfs-interface

I have noticed that this interface:
https://github.com/openbmc/phosphor-dbus-interfaces/blob/master/xyz/openbmc_project/Sensor/Value.interface.yaml
is already exposing something like MinValue and MaxValue,
but current implementation in dbus-sensors always sets these
attributes to some const values.
My understanding of the power capping values is that they could be used as these
MinValue and MaxValue if hwmon provides them otherwise some default
should be used as it is now.


My questions:
1. Should I create a new interface for the capping readings?
2. Or should I extend the existing Value.interface.yaml with new
attributes like MinCapValue, MaxCapValue?
3  Or the correct approach would be to read the cap values if provided
and expose them under already existing MinValue, MaxValue?


Regards,
Zbigniew.