Add service file to synchronize INPUT_HISTORY data

During the power on sequence, the power supplies should have their
INPUT_HISTORY data synchronized. This can be accomplished by toggling
the PS_FFS_N GPIO pin low then high. Use existing phosphor-gpio-util
application to accomplish this. This INPUT_HISTORY data will be used
later for telemetry data. Do not toggle on reboot with power on.

Change-Id: I1e90914827e0e450f8950384d2868a9c730e5ee9
Signed-off-by: Brandon Wyman <bjwyman@gmail.com>
diff --git a/meta-witherspoon/recipes-phosphor/power/witherspoon-power-supply-sync/witherspoon-power-supply-sync.service b/meta-witherspoon/recipes-phosphor/power/witherspoon-power-supply-sync/witherspoon-power-supply-sync.service
new file mode 100644
index 0000000..005a014
--- /dev/null
+++ b/meta-witherspoon/recipes-phosphor/power/witherspoon-power-supply-sync/witherspoon-power-supply-sync.service
@@ -0,0 +1,14 @@
+[Unit]
+Description=Witherspoon Power Supply Input History SYNC
+Wants=obmc-power-start-pre@0.target
+After=obmc-power-start-pre@0.target
+Wants=obmc-chassis-poweron@0.target
+Before=obmc-chassis-poweron@0.target
+ConditionPathExists=!/run/openbmc/chassis@0-on
+
+[Service]
+ExecStart=/usr/bin/env phosphor-gpio-util --gpio=105 --path=/dev/gpiochip0 --delay=5 --action=low_high
+SyslogIdentifier=witherspoon-power-supply-sync
+
+[Install]
+RequiredBy=obmc-chassis-poweron@0.target