Updates and future changes on phosphor-power

[Lei YU]

On Tue, Dec 10, 2019 at 5:10 AM Kun Yi <kunyi at google.com> wrote:
>
> Hello Lei,
>
> We have some interest to help contribute to the phosphor-power utils.
>

Great!

>
> Will phosphor-power provide PMBus fault status bits monitoring?

Yes, it already does monitor PMBus fault, see [power_supply.cpp#L134][1]


> How is it co-operating with phosphor-hwmon or dbus-sensors when reading sensor data from the same PSU device over the same i2c bus?

As far as I know, it does not co-operates with phosphor-hwmon (and I
am not familiar with dbus-sensors). @Matt Spinler correct me if I am
wrong.
Instead, it sends the error log to logging service with the inventory
path when the error is found. See [power_supply.cpp#L309][2]
And when the error is gone, it resolves the error by setting the
`Resolved` property of the log. See [power_supply.cpp#L282]

There is a [fault-monitor][4] in phosphor-led-manager that monitors
the error logs in logging service, and assert/deassert the related
fault LED group.
So the fault LED will be turned on when an error occurs, and turned
off when the error is resolved or cleared.

[1]: https://github.com/openbmc/phosphor-power/blob/1d103428e50ec000372e6b1c2bccc8ee92ddbc89/power-supply/power_supply.cpp#L134
[2]: https://github.com/openbmc/phosphor-power/blob/1d103428e50ec000372e6b1c2bccc8ee92ddbc89/power-supply/power_supply.cpp#L309
[3]: https://github.com/openbmc/phosphor-power/blob/1d103428e50ec000372e6b1c2bccc8ee92ddbc89/power-supply/power_supply.cpp#L282
[4]: https://github.com/openbmc/phosphor-led-manager/tree/master/fault-monitor