watchdog: WatchDog Timer Driver Core - Add WDIOC_KEEPALIVE ioctl

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>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
index 00a611293065..2fb4cecd50d8 100644
--- a/drivers/watchdog/watchdog_dev.c
+++ b/drivers/watchdog/watchdog_dev.c
@@ -120,6 +120,11 @@ 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_KEEPALIVEPING))
+                        return -EOPNOTSUPP;
+                watchdog_ping(wdd);
+                return 0;
         default:
                 return -ENOTTY;
         }