tree 6d91a179d0a8ce22a7c4cce28172ec7cefba4826
parent ce540f3c9fb61f9711726cbbe86f42f55e768d42
author Shawn McCarney <shawnmm@us.ibm.com> 1621350473 -0500
committer Shawn McCarney <shawnmm@us.ibm.com> 1621580342 -0500

regulators: Enable sensor monitoring

Enable sensor monitoring in the phosphor-regulators application.

Previous commits implemented the majority of the sensor monitoring
support.  This commit contains the last set of changes needed to enable
monitoring for the entire application.

Modify the top level Manager class to enable or disable monitoring based
on the D-Bus 'monitor' method.  This method is called by the regsctl
command line tool.  Service files use regsctl to enable monitoring
during power on and disable monitoring during power off.

When monitoring is enabled, set a repeating, one-second timer.  When the
timer expires, execute one sensor monitoring cycle for all voltage
regulator sensors.

When monitoring is disabled, turn off the timer.  Put all the sensors in
an inactive state, indicating they are no longer being updated.  They
will remain in this state until the system is powered on again.

Tested:
* Verified sensor monitoring is enabled when chassis is powered on.
* Verified sensor monitoring is disabled when chassis is powered off.
* Verified voltage regulator sensors are read once per second while
  monitoring is enabled.
* Verified sensors are published on D-Bus when monitoring is enabled.
* Verified sensors remain on D-Bus but are put in an inactive state when
  monitoring is disabled.
* Verified sensors are not read when monitoring is disabled.
* Tested where D-Bus queries to obtain current power state fail with a
  D-Bus exception.
* Verified sensor monitoring is enabled if BMC is reset while chassis is
  powered on.
* Verified sensor monitoring is enabled if regulators application is
  stopped and re-started while chassis is powered on.
* For complete test plan, see
  https://gist.github.com/smccarney/0afa4a50afcf9f0d47e1a21ebe33dbfc

Signed-off-by: Shawn McCarney <shawnmm@us.ibm.com>
Change-Id: Ic85d4baa0a53e57bd2a494611d70a76ae7b135f7