linux/drivers/watchdog/watchdog_pretimeout.h
Vladimir Zapolskiy 53f96cee1a watchdog: pretimeout: add option to select a pretimeout governor in runtime
The change converts watchdog device attribute "pretimeout_governor" from
read-only to read-write type to allow users to select a desirable
watchdog pretimeout governor in runtime, e.g.

  % echo -n panic > /sys/..../watchdog/watchdog0/pretimeout

To get this working a list of registered pretimeout governors is created
and a new helper function watchdog_pretimeout_governor_set() is exported
to watchdog_dev.c.

If a selected governor is gone, a watchdog device pretimeout notification
is delegated to a default built-in pretimeout governor.

Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-10-08 10:27:20 +02:00

55 lines
1.5 KiB
C

#ifndef __WATCHDOG_PRETIMEOUT_H
#define __WATCHDOG_PRETIMEOUT_H
#define WATCHDOG_GOV_NAME_MAXLEN 20
struct watchdog_device;
struct watchdog_governor {
const char name[WATCHDOG_GOV_NAME_MAXLEN];
void (*pretimeout)(struct watchdog_device *wdd);
};
#if IS_ENABLED(CONFIG_WATCHDOG_PRETIMEOUT_GOV)
/* Interfaces to watchdog pretimeout governors */
int watchdog_register_governor(struct watchdog_governor *gov);
void watchdog_unregister_governor(struct watchdog_governor *gov);
/* Interfaces to watchdog_dev.c */
int watchdog_register_pretimeout(struct watchdog_device *wdd);
void watchdog_unregister_pretimeout(struct watchdog_device *wdd);
int watchdog_pretimeout_governor_get(struct watchdog_device *wdd, char *buf);
int watchdog_pretimeout_governor_set(struct watchdog_device *wdd,
const char *buf);
#if IS_ENABLED(CONFIG_WATCHDOG_PRETIMEOUT_DEFAULT_GOV_NOOP)
#define WATCHDOG_PRETIMEOUT_DEFAULT_GOV "noop"
#elif IS_ENABLED(CONFIG_WATCHDOG_PRETIMEOUT_DEFAULT_GOV_PANIC)
#define WATCHDOG_PRETIMEOUT_DEFAULT_GOV "panic"
#endif
#else
static inline int watchdog_register_pretimeout(struct watchdog_device *wdd)
{
return 0;
}
static inline void watchdog_unregister_pretimeout(struct watchdog_device *wdd)
{
}
static inline int watchdog_pretimeout_governor_get(struct watchdog_device *wdd,
char *buf)
{
return -EINVAL;
}
static inline int watchdog_pretimeout_governor_set(struct watchdog_device *wdd,
const char *buf)
{
return -EINVAL;
}
#endif
#endif