1 files changed, 24 insertions, 0 deletions

diff --git a/include/linux/watchdog.h b/include/linux/watchdog.h
index 7047bc7f8106..35a4d8185b51 100644
--- a/include/linux/watchdog.h
+++ b/include/linux/watchdog.h
@@ -19,6 +19,7 @@
 struct watchdog_ops;
 struct watchdog_device;
 struct watchdog_core_data;
+struct watchdog_governor;
 
 /** struct watchdog_ops - The watchdog-devices operations
  *
@@ -28,6 +29,7 @@ struct watchdog_core_data;
  * @ping:       The routine that sends a keepalive ping to the watchdog device.
  * @status:     The routine that shows the status of the watchdog device.
  * @set_timeout:The routine for setting the watchdog devices timeout value (in seconds).
+ * @set_pretimeout:The routine for setting the watchdog devices pretimeout.
  * @get_timeleft:The routine that gets the time left before a reset (in seconds).
  * @restart:    The routine for restarting the machine.
  * @ioctl:      The routines that handles extra ioctl calls.
@@ -46,6 +48,7 @@ struct watchdog_ops {
         int (*ping)(struct watchdog_device *);
         unsigned int (*status)(struct watchdog_device *);
         int (*set_timeout)(struct watchdog_device *, unsigned int);
+        int (*set_pretimeout)(struct watchdog_device *, unsigned int);
         unsigned int (*get_timeleft)(struct watchdog_device *);
         int (*restart)(struct watchdog_device *, unsigned long, void *);
         long (*ioctl)(struct watchdog_device *, unsigned int, unsigned long);
@@ -59,8 +62,10 @@ struct watchdog_ops {
  *              watchdog device.
  * @info:       Pointer to a watchdog_info structure.
  * @ops:        Pointer to the list of watchdog operations.
+ * @gov:        Pointer to watchdog pretimeout governor.
  * @bootstatus: Status of the watchdog device at boot.
  * @timeout:    The watchdog devices timeout value (in seconds).
+ * @pretimeout: The watchdog devices pre_timeout value.
  * @min_timeout:The watchdog devices minimum timeout value (in seconds).
  * @max_timeout:The watchdog devices maximum timeout value (in seconds)
  *              as configurable from user space. Only relevant if
@@ -94,8 +99,10 @@ struct watchdog_device {
         const struct attribute_group **groups;
         const struct watchdog_info *info;
         const struct watchdog_ops *ops;
+        const struct watchdog_governor *gov;
         unsigned int bootstatus;
         unsigned int timeout;
+        unsigned int pretimeout;
         unsigned int min_timeout;
         unsigned int max_timeout;
         unsigned int min_hw_heartbeat_ms;
@@ -163,6 +170,13 @@ static inline bool watchdog_timeout_invalid(struct watchdog_device *wdd, unsigne
                  t > wdd->max_timeout);
 }
 
+/* Use the following function to check if a pretimeout value is invalid */
+static inline bool watchdog_pretimeout_invalid(struct watchdog_device *wdd,
+                                               unsigned int t)
+{
+        return t && wdd->timeout && t >= wdd->timeout;
+}
+
 /* Use the following functions to manipulate watchdog driver specific data */
 static inline void watchdog_set_drvdata(struct watchdog_device *wdd, void *data)
 {
@@ -174,6 +188,16 @@ static inline void *watchdog_get_drvdata(struct watchdog_device *wdd)
         return wdd->driver_data;
 }
 
+/* Use the following functions to report watchdog pretimeout event */
+#if IS_ENABLED(CONFIG_WATCHDOG_PRETIMEOUT_GOV)
+void watchdog_notify_pretimeout(struct watchdog_device *wdd);
+#else
+static inline void watchdog_notify_pretimeout(struct watchdog_device *wdd)
+{
+        pr_alert("watchdog%d: pretimeout event\n", wdd->id);
+}
+#endif
+
 /* drivers/watchdog/watchdog_core.c */
 void watchdog_set_restart_priority(struct watchdog_device *wdd, int priority);
 extern int watchdog_init_timeout(struct watchdog_device *wdd,