diff --git a/spi.c b/spi.c
index 9f8fb89..6f77e5c 100644
--- a/spi.c
+++ b/spi.c
@@ -163,7 +163,7 @@
 
 int register_spi_master(const struct spi_master *mst, size_t max_rom_decode, void *data)
 {
-	struct registered_master rmst;
+	struct registered_master rmst = { 0 };
 
 	if (mst->shutdown) {
 		if (register_shutdown(mst->shutdown, data)) {