diff --git a/Documentation/watchdog/watchdog-kernel-api.rst b/Documentation/watchdog/watchdog-kernel-api.rst
index 068a55ee0d4a..baf44e986b07 100644
--- a/Documentation/watchdog/watchdog-kernel-api.rst
+++ b/Documentation/watchdog/watchdog-kernel-api.rst
@@ -336,3 +336,15 @@ an action is taken by a preconfigured pretimeout governor preassigned to
 the watchdog device. If watchdog pretimeout governor framework is not
 enabled, watchdog_notify_pretimeout() prints a notification message to
 the kernel log buffer.
+
+To set the last known HW keepalive time for a watchdog, the following function
+should be used::
+
+  int watchdog_set_last_hw_keepalive(struct watchdog_device *wdd,
+                                     unsigned int last_ping_ms)
+
+This function must be called immediately after watchdog registration. It
+sets the last known hardware heartbeat to have happened last_ping_ms before
+current time. Calling this is only needed if the watchdog is already running
+when probe is called, and the watchdog can only be pinged after the
+min_hw_heartbeat_ms time has passed from the last ping.
diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
index 0ad1c393c00e..531e74994b61 100644
--- a/drivers/watchdog/watchdog_dev.c
+++ b/drivers/watchdog/watchdog_dev.c
@@ -1138,6 +1138,36 @@ void watchdog_dev_unregister(struct watchdog_device *wdd)
 	watchdog_cdev_unregister(wdd);
 }
 
+/*
+ *	watchdog_set_last_hw_keepalive: set last HW keepalive time for watchdog
+ *	@wdd: watchdog device
+ *	@last_ping_ms: time since last HW heartbeat
+ *
+ *	Adjusts the last known HW keepalive time for a watchdog timer.
+ *	This is needed if the watchdog is already running when the probe
+ *	function is called, and it can't be pinged immediately. This
+ *	function must be called immediately after watchdog registration,
+ *	and min_hw_heartbeat_ms must be set for this to be useful.
+ */
+int watchdog_set_last_hw_keepalive(struct watchdog_device *wdd,
+				   unsigned int last_ping_ms)
+{
+	struct watchdog_core_data *wd_data;
+	ktime_t now;
+
+	if (!wdd)
+		return -EINVAL;
+
+	wd_data = wdd->wd_data;
+
+	now = ktime_get();
+
+	wd_data->last_hw_keepalive = ktime_sub(now, ms_to_ktime(last_ping_ms));
+
+	return __watchdog_ping(wdd);
+}
+EXPORT_SYMBOL_GPL(watchdog_set_last_hw_keepalive);
+
 /*
  *	watchdog_dev_init: init dev part of watchdog core
  *
diff --git a/include/linux/watchdog.h b/include/linux/watchdog.h
index 1464ce6ffa31..9b19e6bb68b5 100644
--- a/include/linux/watchdog.h
+++ b/include/linux/watchdog.h
@@ -210,6 +210,8 @@ extern int watchdog_init_timeout(struct watchdog_device *wdd,
 extern int watchdog_register_device(struct watchdog_device *);
 extern void watchdog_unregister_device(struct watchdog_device *);
 
+int watchdog_set_last_hw_keepalive(struct watchdog_device *, unsigned int);
+
 /* devres register variant */
 int devm_watchdog_register_device(struct device *dev, struct watchdog_device *);