diff options
Diffstat (limited to 'include/linux/watchdog.h')
| -rw-r--r-- | include/linux/watchdog.h | 148 |
1 files changed, 148 insertions, 0 deletions
diff --git a/include/linux/watchdog.h b/include/linux/watchdog.h new file mode 100644 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 */ |