2 files changed, 8 insertions, 0 deletions

diff --git a/Documentation/watchdog/watchdog-kernel-api.txt b/Documentation/watchdog/watchdog-kernel-api.txt
index 2bdc6dc6e04c..abbcf2ce8f62 100644
--- a/Documentation/watchdog/watchdog-kernel-api.txt
+++ b/Documentation/watchdog/watchdog-kernel-api.txt
@@ -101,6 +101,9 @@ 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/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;
         }