[RFC] [PATCH 3/10] Generic Watchdog Timer Driver

[Wim Van Sebroeck <wim@iguana.be>]

commit 87af8029a114af16d696047167d482624a1c9334
Author: Wim Van Sebroeck <wim@iguana.be>
Date:   Fri Jun 18 09:03:14 2010 +0000

    watchdog: WatchDog Timer Driver Core - Part 3
    
    This part add's the WDIOC_KEEPALIVE ioctl functionality to the
    WatchDog Timer Driver Core framework. Please note that the
    WDIOF_KEEPALIVEPING bit has to be set in the watchdog_info
    options field.
    
    Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
    Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

diff --git a/Documentation/watchdog/src/watchdog-with-timer-example.c b/Documentation/watchdog/src/watchdog-with-timer-example.c
index ed7852a..d64cac6 100644
--- a/Documentation/watchdog/src/watchdog-with-timer-example.c
+++ b/Documentation/watchdog/src/watchdog-with-timer-example.c
@@ -117,6 +117,7 @@ static int wdt_stop(struct watchdog_device *wdd)
  */
 static const struct watchdog_info wdt_info = {
 	.identity =	DRV_NAME,
+	.options =	WDIOF_KEEPALIVEPING,
 };
 
 static const struct watchdog_ops wdt_ops = {
diff --git a/Documentation/watchdog/watchdog-kernel-api.txt b/Documentation/watchdog/watchdog-kernel-api.txt
index 9418d4c..4a68e5e 100644
--- a/Documentation/watchdog/watchdog-kernel-api.txt
+++ b/Documentation/watchdog/watchdog-kernel-api.txt
@@ -96,6 +96,9 @@ they are supported. These optional routines/operations are:
   the watchdog timer driver core does: to send a keepalive ping to the watchdog
   timer hardware it will either use the ping operation (when available) or the
   start operation (when the ping operation is not available).
+  (Note: the WDIOC_KEEPALIVE ioctl call will only be active when the
+  WDIOF_KEEPALIVEPING bit has been set in the option field on the watchdog's
+  info structure).
 * status: this routine checks the status of the watchdog timer device. The
   status of the device is reported with watchdog WDIOF_* status flags/bits.
 
diff --git a/drivers/watchdog/core/watchdog_dev.c b/drivers/watchdog/core/watchdog_dev.c
index ad08a93..0d2ed1d 100644
--- a/drivers/watchdog/core/watchdog_dev.c
+++ b/drivers/watchdog/core/watchdog_dev.c
@@ -151,6 +151,11 @@ static long watchdog_ioctl(struct file *file, unsigned int cmd,
 		return put_user(val, p);
 	case WDIOC_GETBOOTSTATUS:
 		return put_user(wdd->bootstatus, p);
+	case WDIOC_KEEPALIVE:
+		if (!(wdd->info->options & WDIOF_MAGICCLOSE))
+			return -EOPNOTSUPP;
+		watchdog_ping(wdd);
+		return 0;
 	default:
 		return -ENOTTY;
 	}
diff --git a/include/linux/watchdog.h b/include/linux/watchdog.h
index 4d00bf8..a41dca3 100644
--- a/include/linux/watchdog.h
+++ b/include/linux/watchdog.h
@@ -69,12 +69,15 @@ struct watchdog_ops {
 	int (*stop)(struct watchdog_device *);
 	/* optional operations */
 	int (*ping)(struct watchdog_device *);
+	int (*status)(struct watchdog_device *);
 };
 
 /* The structure that defines a watchdog device */
 struct watchdog_device {
 	char *name;
+	const struct watchdog_info *info;
 	const struct watchdog_ops *ops;
+	int bootstatus;
 	long status;
 #define WDOG_DEV_OPEN		1	/* is the watchdog opened via
 					 * /dev/watchdog */