v4.19.13 snapshot.
diff --git a/include/linux/watchdog.h b/include/linux/watchdog.h
new file mode 100644
index 0000000..44985c4
--- /dev/null
+++ b/include/linux/watchdog.h
@@ -0,0 +1,219 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Generic watchdog defines. Derived from..
+ *
+ * Berkshire PC Watchdog Defines
+ * by Ken Hollis <khollis@bitgate.com>
+ *
+ */
+#ifndef _LINUX_WATCHDOG_H
+#define _LINUX_WATCHDOG_H
+
+
+#include <linux/bitops.h>
+#include <linux/cdev.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/notifier.h>
+#include <uapi/linux/watchdog.h>
+
+struct watchdog_ops;
+struct watchdog_device;
+struct watchdog_core_data;
+struct watchdog_governor;
+
+/** struct watchdog_ops - The watchdog-devices operations
+ *
+ * @owner: The module owner.
+ * @start: The routine for starting the watchdog device.
+ * @stop: The routine for stopping the watchdog device.
+ * @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.
+ *
+ * The watchdog_ops structure contains a list of low-level operations
+ * that control a watchdog device. It also contains the module that owns
+ * these operations. The start and stop function are mandatory, all other
+ * functions are optional.
+ */
+struct watchdog_ops {
+ struct module *owner;
+ /* mandatory operations */
+ int (*start)(struct watchdog_device *);
+ int (*stop)(struct watchdog_device *);
+ /* optional operations */
+ 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);
+};
+
+/** struct watchdog_device - The structure that defines a watchdog device
+ *
+ * @id: The watchdog's ID. (Allocated by watchdog_register_device)
+ * @parent: The parent bus device
+ * @groups: List of sysfs attribute groups to create when creating the
+ * 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
+ * max_hw_heartbeat_ms is not provided.
+ * @min_hw_heartbeat_ms:
+ * Hardware limit for minimum time between heartbeats,
+ * in milli-seconds.
+ * @max_hw_heartbeat_ms:
+ * Hardware limit for maximum timeout, in milli-seconds.
+ * Replaces max_timeout if specified.
+ * @reboot_nb: The notifier block to stop watchdog on reboot.
+ * @restart_nb: The notifier block to register a restart function.
+ * @driver_data:Pointer to the drivers private data.
+ * @wd_data: Pointer to watchdog core internal data.
+ * @status: Field that contains the devices internal status bits.
+ * @deferred: Entry in wtd_deferred_reg_list which is used to
+ * register early initialized watchdogs.
+ *
+ * The watchdog_device structure contains all information about a
+ * watchdog timer device.
+ *
+ * The driver-data field may not be accessed directly. It must be accessed
+ * via the watchdog_set_drvdata and watchdog_get_drvdata helpers.
+ *
+ * The lock field is for watchdog core internal use only and should not be
+ * touched.
+ */
+struct watchdog_device {
+ int id;
+ struct device *parent;
+ 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;
+ unsigned int max_hw_heartbeat_ms;
+ struct notifier_block reboot_nb;
+ struct notifier_block restart_nb;
+ void *driver_data;
+ struct watchdog_core_data *wd_data;
+ unsigned long status;
+/* Bit numbers for status flags */
+#define WDOG_ACTIVE 0 /* Is the watchdog running/active */
+#define WDOG_NO_WAY_OUT 1 /* Is 'nowayout' feature set ? */
+#define WDOG_STOP_ON_REBOOT 2 /* Should be stopped on reboot */
+#define WDOG_HW_RUNNING 3 /* True if HW watchdog running */
+#define WDOG_STOP_ON_UNREGISTER 4 /* Should be stopped on unregister */
+ struct list_head deferred;
+};
+
+#define WATCHDOG_NOWAYOUT IS_BUILTIN(CONFIG_WATCHDOG_NOWAYOUT)
+#define WATCHDOG_NOWAYOUT_INIT_STATUS (WATCHDOG_NOWAYOUT << WDOG_NO_WAY_OUT)
+
+/* Use the following function to check whether or not the watchdog is active */
+static inline bool watchdog_active(struct watchdog_device *wdd)
+{
+ return test_bit(WDOG_ACTIVE, &wdd->status);
+}
+
+/*
+ * Use the following function to check whether or not the hardware watchdog
+ * is running
+ */
+static inline bool watchdog_hw_running(struct watchdog_device *wdd)
+{
+ return test_bit(WDOG_HW_RUNNING, &wdd->status);
+}
+
+/* Use the following function to set the nowayout feature */
+static inline void watchdog_set_nowayout(struct watchdog_device *wdd, bool nowayout)
+{
+ if (nowayout)
+ set_bit(WDOG_NO_WAY_OUT, &wdd->status);
+}
+
+/* Use the following function to stop the watchdog on reboot */
+static inline void watchdog_stop_on_reboot(struct watchdog_device *wdd)
+{
+ set_bit(WDOG_STOP_ON_REBOOT, &wdd->status);
+}
+
+/* Use the following function to stop the watchdog when unregistering it */
+static inline void watchdog_stop_on_unregister(struct watchdog_device *wdd)
+{
+ set_bit(WDOG_STOP_ON_UNREGISTER, &wdd->status);
+}
+
+/* Use the following function to check if a timeout value is invalid */
+static inline bool watchdog_timeout_invalid(struct watchdog_device *wdd, unsigned int t)
+{
+ /*
+ * The timeout is invalid if
+ * - the requested value is larger than UINT_MAX / 1000
+ * (since internal calculations are done in milli-seconds),
+ * or
+ * - the requested value is smaller than the configured minimum timeout,
+ * or
+ * - a maximum hardware timeout is not configured, a maximum timeout
+ * is configured, and the requested value is larger than the
+ * configured maximum timeout.
+ */
+ return t > UINT_MAX / 1000 || t < wdd->min_timeout ||
+ (!wdd->max_hw_heartbeat_ms && wdd->max_timeout &&
+ 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)
+{
+ wdd->driver_data = data;
+}
+
+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,
+ unsigned int timeout_parm, struct device *dev);
+extern int watchdog_register_device(struct watchdog_device *);
+extern void watchdog_unregister_device(struct watchdog_device *);
+
+/* devres register variant */
+int devm_watchdog_register_device(struct device *dev, struct watchdog_device *);
+
+#endif /* ifndef _LINUX_WATCHDOG_H */