In some cases, platform thermal driver may report invalid trip points,
thermal core should not take any action for these trip points.
This fixed a regression that bogus trip point starts to screw up thermal
control on some Lenovo laptops, after
commit bb431ba26c
Author: Zhang Rui <[email protected]>
Date: Fri Oct 30 16:31:47 2015 +0800
Thermal: initialize thermal zone device correctly
After thermal zone device registered, as we have not read any
temperature before, thus tz->temperature should not be 0,
which actually means 0C, and thermal trend is not available.
In this case, we need specially handling for the first
thermal_zone_device_update().
Both thermal core framework and step_wise governor is
enhanced to handle this. And since the step_wise governor
is the only one that uses trends, so it's the only thermal
governor that needs to be updated.
Tested-by: Manuel Krause <[email protected]>
Tested-by: szegad <[email protected]>
Tested-by: prash <[email protected]>
Tested-by: amish <[email protected]>
Tested-by: Matthias <[email protected]>
Reviewed-by: Javi Merino <[email protected]>
Signed-off-by: Zhang Rui <[email protected]>
Signed-off-by: Chen Yu <[email protected]>
CC: <[email protected]> #3.18+
Link: https://bugzilla.redhat.com/show_bug.cgi?id=1317190
Link: https://bugzilla.kernel.org/show_bug.cgi?id=114551
Signed-off-by: Zhang Rui <[email protected]>
81ad4276b5