Phosphor-fan-present only update fan Functional for xyz.openbmc_project.Inventory.Manager

[Matthew Barth]

On 12/15/20 9:01 PM, Thu Nguyen wrote:
> Hi,
>
> I would like to ask about current behavior of phosphor-fan-present.
>
> When I unplug one fan, phosphor-fan-monitor will only update the 
> Functional Dbus properties of 
> /system/chassis/motherboard/FAN3_1/FAN3_1 and 
> /system/chassis/motherboard/FAN3_1 of inventory interface to false.
>
> But not for "/xyz/openbmc_project/sensors/fan_tach/FAN3_1" of hwmon 
> interface.
>
> Below is test log:
>
> ~# busctl get-property xyz.openbmc_project.Inventory.Manager 
> /xyz/openbmc_project/inventory/system/chassis/motherboard/FAN4_2/FAN4_2 
> xyz.openbmc_project.State.Decorator.OperationalStatus Functional
> b false
> ~# busctl get-property xyz.openbmc_project.Inventory.Manager 
> /xyz/openbmc_project/inventory/system/chassis/motherboard/FAN4_2 
> xyz.openbmc_project.State.Decorator.OperationalStatus Functional
> b false
> ~# busctl get-property xyz.openbmc_project.Hwmon-1644477290.Hwmon1 
> /xyz/openbmc_project/sensors/fan_tach/FAN4_2 
> xyz.openbmc_project.State.Decorator.OperationalStatus Functional
> b true
>
> Is this the expected behavior?
>
Yes. The phosphor-fan-monitor application is configured to only update 
the functional status of the fan (and/or individual fan rotors) within 
inventory. This is separate than the functional state of the device 
providing the tach sensors themselves since, for example, the sensor can 
be correctly reporting 0 RPMs for a feedback speed, however that should 
be shown as a nonfunctional fan needing to be replaced and not the 
device providing the tach sensors of the fan.

> Regards.
>
> Thu Nguyen.
>
Matt