Hi!
Add a sysfs node code to report effective cooling of all cooling devices attached to each trip points of a thermal zone. The cooling data reported will be absolute if the higher temperature trip points are arranged first otherwise the cooling stats is the cumulative effect of the earlier invoked cooling handlers.
The basic assumption is that cooling devices will bring down the temperature in a symmetric manner and those statistics can be stored back and used for further tuning of the system.
/sys fs should be one-value-per-file, talk to gregkh.