tree 97e7c33eac2da5a2021e4c886d5053f35d53a376
parent 838529b5400129e8a3a8007ca83102c7733ec01c
author Josh Lehan <krellan@google.com> 1596784374 -0700
committer Josh Lehan <krellan@google.com> 1599457933 -0700

TachSensor: Accept PowerState from configuration

Accept the PowerState configuration parameter,
similar to other sensors.
This allows it to optionally be set to "Always",
while still preserving the default of "On".

Some systems have their chassis fans not tied to host power,
so they can continue working, even when host powered off,
and "Always" allows the BMC to continue to monitor them.

Tested: Without this patch, or set to "On",
the tachometers show RPM of 0,
even though the fans are still running correctly,
when host is powered off (but BMC and chassis fans
still have power). After this patch, and setting "Always",
the tachometers once again indicate proper RPM.

Signed-off-by: Josh Lehan <krellan@google.com>
Change-Id: I1774f0bec180f52e18d37500fcdd87d32620d519