[PATCH v2 1/5] watchdog: Add API to trigger reboots
From: linux@roeck-us.net (Guenter Roeck)
Date: 2014-05-10 00:31:42
Also in:
linux-watchdog, lkml
Subsystem:
the rest, watchdog device drivers · Maintainers:
Linus Torvalds, Wim Van Sebroeck, Guenter Roeck
Some hardware implements reboot through its watchdog hardware, for example by triggering a watchdog timeout. Platform specific code starts to spread into watchdog drivers, typically by setting pointers to a callback functions which is then called from the platform reset handler. To simplify code and provide a unified API to trigger reboots by watchdog drivers, provide a single API to trigger such reboots through the watchdog subsystem. Acked-by: Maxime Ripard <redacted> Acked-by: Arnd Bergmann <arnd@arndb.de> Tested-by: Jonas Jensen <redacted> Acked-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Guenter Roeck <linux@roeck-us.net> --- v2: Remove unnecessary check for ops in reboot function drivers/watchdog/watchdog_core.c | 15 +++++++++++++++ include/linux/watchdog.h | 11 +++++++++++ 2 files changed, 26 insertions(+)
diff --git a/drivers/watchdog/watchdog_core.c b/drivers/watchdog/watchdog_core.c
index cec9b55..edfd9c5 100644
--- a/drivers/watchdog/watchdog_core.c
+++ b/drivers/watchdog/watchdog_core.c@@ -43,6 +43,15 @@ static DEFINE_IDA(watchdog_ida); static struct class *watchdog_class; +static struct watchdog_device *wdd_reboot_dev; + +void watchdog_do_reboot(enum reboot_mode mode, const char *cmd) +{ + if (wdd_reboot_dev) + wdd_reboot_dev->ops->reboot(wdd_reboot_dev, mode, cmd); +} +EXPORT_SYMBOL(watchdog_do_reboot); + static void watchdog_check_min_max_timeout(struct watchdog_device *wdd) { /*
@@ -162,6 +171,9 @@ int watchdog_register_device(struct watchdog_device *wdd) return ret; } + if (wdd->ops->reboot) + wdd_reboot_dev = wdd; + return 0; } EXPORT_SYMBOL_GPL(watchdog_register_device);
@@ -181,6 +193,9 @@ void watchdog_unregister_device(struct watchdog_device *wdd) if (wdd == NULL) return; + if (wdd == wdd_reboot_dev) + wdd_reboot_dev = NULL; + devno = wdd->cdev.dev; ret = watchdog_dev_unregister(wdd); if (ret)
diff --git a/include/linux/watchdog.h b/include/linux/watchdog.h
index 2a3038e..0d204af 100644
--- a/include/linux/watchdog.h
+++ b/include/linux/watchdog.h@@ -12,6 +12,7 @@ #include <linux/bitops.h> #include <linux/device.h> #include <linux/cdev.h> +#include <linux/reboot.h> #include <uapi/linux/watchdog.h> struct watchdog_ops;
@@ -23,6 +24,7 @@ struct watchdog_device; * @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. + * @reboot: The routine for rebooting the system * @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.
@@ -42,6 +44,8 @@ struct watchdog_ops { int (*stop)(struct watchdog_device *); /* optional operations */ int (*ping)(struct watchdog_device *); + void (*reboot)(struct watchdog_device *, enum reboot_mode, + const char *); unsigned int (*status)(struct watchdog_device *); int (*set_timeout)(struct watchdog_device *, unsigned int); unsigned int (*get_timeleft)(struct watchdog_device *);
@@ -142,4 +146,11 @@ extern int watchdog_init_timeout(struct watchdog_device *wdd, extern int watchdog_register_device(struct watchdog_device *); extern void watchdog_unregister_device(struct watchdog_device *); +#ifdef CONFIG_WATCHDOG_CORE +extern void watchdog_do_reboot(enum reboot_mode mode, const char *cmd); +#else +static inline void watchdog_do_reboot(enum reboot_mode mode, + const char *cmd) { } +#endif + #endif /* ifndef _LINUX_WATCHDOG_H */
--
1.9.1