Index: uspace/drv/time/cmos-rtc/cmos-rtc.c
===================================================================
--- uspace/drv/time/cmos-rtc/cmos-rtc.c	(revision fa18523547f587da07046f2697155b9dae6897fa)
+++ uspace/drv/time/cmos-rtc/cmos-rtc.c	(revision a8b80863d380d342181cded674e9038241702afb)
@@ -352,9 +352,8 @@
 	fibril_mutex_unlock(&rtc->mutex);
 
+	/* Try to normalize the content of the tm structure */
 	time_t r = mktime(t);
-	if (r < 0)
-		return EINVAL;
-
-	return EOK;
+
+	return r < 0 ? EINVAL : EOK;
 }
 
@@ -375,4 +374,5 @@
 	rtc_t *rtc = RTC_FROM_FNODE(fun);
 
+	/* Try to normalize the content of the tm structure */
 	if (mktime(t) < 0)
 		return EINVAL;