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diff --git a/meta-facebook/meta-wedge/recipes-wedge/fan-ctrl/fan-ctrl/watchdog.h b/meta-facebook/meta-wedge/recipes-wedge/fan-ctrl/fan-ctrl/watchdog.h
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+/*
+ * watchdog
+ *
+ * Copyright 2014-present Facebook. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * Utility library to handle the aspeed watchdog. Only one watchdog
+ * should be in use at any time throughout the entire system (multiple users
+ * will not cause adverse effects but the behavior of the watchdog becomes
+ * undefined).
+ *
+ * The watchdog can be started in either manual or automatic mode. In manual
+ * mode, the watchdog has to be constantly reset by the user via the
+ * kick_watchdog() function. Under automatic mode, the watchdog will
+ * run in a separate thread and reset the timer on its own so no intervention
+ * is required from the user.
+ *
+ * In both modes, the watchdog timer will not stop when the process is
+ * terminated, unless a call to stop_watchdog() has been made beforehand, or
+ * if the user runs in manual mode and uses a non persistent watchdog kick.
+ *
+ * The default timeout for the watchdog is 11 seconds. When this time period
+ * elapses, the ARM chip is restarted and the kernel is rebooted. Other
+ * hardware state is not reset, so this may introduce strange behavior on
+ * reboot (example: an I2C bus may be left in the open state, triggering
+ * constant interrupts). In rare cases, this could result in the kernel
+ * failing to fully restart itself and thus preclude the possibility of
+ * reinitializing the watchdog timer. Someone will then have to go over and
+ * physically restart the machine.
+ *
+ * The alternative to the soft reset is to request the watchdog device driver
+ * for a hard reset on timeout. However this will stop the fans. If the
+ * kernel fails to fully boot and restart the fan daemon, the system could
+ * overheat. For this reason, we've chosen to take the risk of a stuck soft
+ * reset instead.
+ *
+ */
+
+/* Forward declarations. */
+int start_watchdog(const int auto_mode);
+enum watchdog_persistent_en {
+  WATCHDOG_SET_PERSISTENT,
+  WATCHDOG_SET_NONPERSISTENT,
+};
+void set_persistent_watchdog(enum watchdog_persistent_en persistent);
+int kick_watchdog();
+void stop_watchdog();