diff --git a/designs/device-tree-gpio-naming.md b/designs/device-tree-gpio-naming.md
index 94d1a5a..4f04042 100644
--- a/designs/device-tree-gpio-naming.md
+++ b/designs/device-tree-gpio-naming.md
@@ -103,6 +103,13 @@
 GPIO, the hardware can then take actions such as reducing the system's
 performance so that it can maintain its powered on state.
 
+#### power-ffs-sync-history
+Output GPIO set by the power managing applications. The IBM Common Form Factor
+power supplies use this line as an input. When set low and left low the power
+supply fans run at full speed (Fans Full Speed). When toggled low, then high,
+it resets the power supply input history (average and maximum power values over
+a time range).
+
 #### 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