diff --git a/cmd/cache.c b/cmd/cache.c
index 233f428..2c68717 100644
--- a/cmd/cache.c
+++ b/cmd/cache.c
@@ -22,7 +22,7 @@
 static int do_icache(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
 	switch (argc) {
-	case 2:			/* on / off	*/
+	case 2:			/* on / off / flush */
 		switch (parse_argv(argv[1])) {
 		case 0:
 			icache_disable();
@@ -33,6 +33,8 @@
 		case 2:
 			invalidate_icache_all();
 			break;
+		default:
+			return CMD_RET_USAGE;
 		}
 		break;
 	case 1:			/* get status */
@@ -54,7 +56,7 @@
 static int do_dcache(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
 	switch (argc) {
-	case 2:			/* on / off */
+	case 2:			/* on / off / flush */
 		switch (parse_argv(argv[1])) {
 		case 0:
 			dcache_disable();
@@ -65,6 +67,8 @@
 		case 2:
 			flush_dcache_all();
 			break;
+		default:
+			return CMD_RET_USAGE;
 		}
 		break;
 	case 1:			/* get status */