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-rw-r--r--include/linux/watchdog.h148
1 files changed, 148 insertions, 0 deletions
diff --git a/include/linux/watchdog.h b/include/linux/watchdog.h
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index 000000000..a746bf521
--- /dev/null
+++ b/include/linux/watchdog.h
@@ -0,0 +1,148 @@
+/*
+ * 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/device.h>
+#include <linux/cdev.h>
+#include <uapi/linux/watchdog.h>
+
+struct watchdog_ops;
+struct watchdog_device;
+
+/** 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.
+ * @get_timeleft:The routine that get's the time that's left before a reset.
+ * @ref: The ref operation for dyn. allocated watchdog_device structs
+ * @unref: The unref operation for dyn. allocated watchdog_device structs
+ * @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 optonal.
+ */
+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);
+ unsigned int (*get_timeleft)(struct watchdog_device *);
+ void (*ref)(struct watchdog_device *);
+ void (*unref)(struct watchdog_device *);
+ 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)
+ * @cdev: The watchdog's Character device.
+ * @dev: The device for our watchdog
+ * @parent: The parent bus device
+ * @info: Pointer to a watchdog_info structure.
+ * @ops: Pointer to the list of watchdog operations.
+ * @bootstatus: Status of the watchdog device at boot.
+ * @timeout: The watchdog devices timeout value.
+ * @min_timeout:The watchdog devices minimum timeout value.
+ * @max_timeout:The watchdog devices maximum timeout value.
+ * @driver-data:Pointer to the drivers private data.
+ * @lock: Lock for watchdog core internal use only.
+ * @status: Field that contains the devices internal status bits.
+ *
+ * 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 cdev cdev;
+ struct device *dev;
+ struct device *parent;
+ const struct watchdog_info *info;
+ const struct watchdog_ops *ops;
+ unsigned int bootstatus;
+ unsigned int timeout;
+ unsigned int min_timeout;
+ unsigned int max_timeout;
+ void *driver_data;
+ struct mutex lock;
+ unsigned long status;
+/* Bit numbers for status flags */
+#define WDOG_ACTIVE 0 /* Is the watchdog running/active */
+#define WDOG_DEV_OPEN 1 /* Opened via /dev/watchdog ? */
+#define WDOG_ALLOW_RELEASE 2 /* Did we receive the magic char ? */
+#define WDOG_NO_WAY_OUT 3 /* Is 'nowayout' feature set ? */
+#define WDOG_UNREGISTERED 4 /* Has the device been unregistered */
+};
+
+#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 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 check if a timeout value is invalid */
+static inline bool watchdog_timeout_invalid(struct watchdog_device *wdd, unsigned int t)
+{
+ return ((wdd->max_timeout != 0) &&
+ (t < wdd->min_timeout || t > wdd->max_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;
+}
+
+/* drivers/watchdog/watchdog_core.c */
+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 *);
+
+#ifdef CONFIG_HARDLOCKUP_DETECTOR
+void watchdog_nmi_disable_all(void);
+void watchdog_nmi_enable_all(void);
+#else
+static inline void watchdog_nmi_disable_all(void) {}
+static inline void watchdog_nmi_enable_all(void) {}
+#endif
+
+#endif /* ifndef _LINUX_WATCHDOG_H */