diff --git a/api/api_storage.c b/api/api_storage.c
index f858f09..8bed2f3 100644
--- a/api/api_storage.c
+++ b/api/api_storage.c
@@ -43,6 +43,9 @@ struct stor_spec {
 
 static struct stor_spec specs[ENUM_MAX] = { { 0, 0, 0, 0, NULL }, };
 
+#ifndef CONFIG_SYS_MMC_MAX_DEVICE
+#define CONFIG_SYS_MMC_MAX_DEVICE	1
+#endif
 
 void dev_stor_init(void)
 {