phosphor-power-sequencer/docs/powering_off.md

3 ## Initiating a power off
6 Redfish command, or a power button on the system enclosure.
8 Whichever method is used, it sets the `state` property to 0 on the
9 `org.openbmc.control.Power` D-Bus interface. The D-Bus object path is
13 The `phosphor-power-sequencer` application only supports powering off the entire
14 system. In a multiple chassis system, `phosphor-power-sequencer` does not
17 ## Determining which chassis to power off
19 In a single chassis system, `phosphor-power-sequencer` will always attempt to
20 power off the chassis.
22 In a multiple chassis system, `phosphor-power-sequencer` will only attempt to
23 power off chassis with the proper status:
25 - `Present` property is true
26 - `Available` property is true (if interface exists)
28 `phosphor-power-sequencer` will set the `state` property to 0 for all chassis.
30 `phosphor-power-sequencer` will set the `pgood` property to 0 for all chassis
33 See [Chassis Status](chassis_status.md) for more information on these
38 `phosphor-power-sequencer` powers off the main (non-standby) voltage rails in a
39 chassis by toggling a named GPIO to the power sequencer device in the chassis.
42 In each chassis being powered off, the power sequencer device powers off the
45 ## Determining when power off is complete
47 When the voltage rails have been powered off in a chassis, the power sequencer
48 device will set the chassis power good (pgood) signal to false.
50 `phosphor-power-sequencer` reads the chassis pgood signal from a named GPIO. For
52 [Monitoring Chassis Power Good](monitoring_chassis_pgood.md).
54 When the chassis power good signal changes to false, `phosphor-power-sequencer`
55 will set the `pgood` property to 0 on the `org.openbmc.control.Power` interface
56 for the **chassis** object path. The power off has finished for that chassis.
59 `phosphor-power-sequencer` will set the `pgood` property to 0 on the
60 `org.openbmc.control.Power` interface for the **system** object path.
62 See [Chassis Status](chassis_status.md) for more information on the `pgood`