diff --git a/os/WaitFor.c b/os/WaitFor.c
index a388cd573..a421e5b2a 100644
--- a/os/WaitFor.c
+++ b/os/WaitFor.c
@@ -416,13 +416,13 @@ NextDPMSTimeout(INT32 timeout)
     switch (DPMSPowerLevel) {
     case DPMSModeOn:
         DPMS_CHECK_TIMEOUT(DPMSStandbyTime)
-
+        /* fallthrough */
     case DPMSModeStandby:
         DPMS_CHECK_TIMEOUT(DPMSSuspendTime)
-
+        /* fallthrough */
     case DPMSModeSuspend:
         DPMS_CHECK_TIMEOUT(DPMSOffTime)
-
+        /* fallthrough */
     default:                   /* DPMSModeOff */
         return 0;
     }