device-tree-gpio-naming: Add power-config-full-load

The power-config-full-load GPIO is intended to communicate to the HW the
expected number of working power supplies for this system model, so that
if the number of power supplies present are less than the expected one,
performance may need to be reduced so the system can maintain its
powered on state.

Change-Id: I9d14b869765df0755262f6e5f14c0fed03736640
Signed-off-by: Adriana Kobylak <anoo@us.ibm.com>
diff --git a/designs/device-tree-gpio-naming.md b/designs/device-tree-gpio-naming.md
index 4a2667a..6f2504c 100644
--- a/designs/device-tree-gpio-naming.md
+++ b/designs/device-tree-gpio-naming.md
@@ -73,9 +73,19 @@
 #### power-chassis-good
 Indicates the power good state of the chassis.
 
+#### power-config-full-load
+Output GPIO set by the power managing application that indicates to the hardware
+the threshold of power supplies that are expected to be present and working for
+this type of system for the case where a system has a model that supports two
+different number of power supplies (example 2 or 4). Default is the lowest
+number of power supplies expected of the two models. In the case when the number
+of power supplies that are present are less than the ones indicated by this
+GPIO, the hardware can then take actions such as reducing the system's
+performance so that it can maintain its powered on state.
+
 #### regulator-standby-faulted
 This GPIO value represents the status of standby power regulator fault detection
-logic. This GPIO is an input only. The status will reflect a regulator 
+logic. This GPIO is an input only. The status will reflect a regulator
 non-faulted condition after AC power cycle when no standby power regulator fault
 condition is present. The status will reflect a standby regulator power faulted
 condition when an unexpected drop in standby power is detected.