1 files changed, 5 insertions, 0 deletions
diff --git a/spi.h b/spi.h
index 15bac4ec5..f5c877cdc 100644
--- a/spi.h
+++ b/spi.h
@@ -29,6 +29,11 @@
 #define JEDEC_RDID_OUTSIZE	0x01
 #define JEDEC_RDID_INSIZE	0x03
 
+/* Read Electronic Signature */
+#define JEDEC_RES		0xab
+#define JEDEC_RES_OUTSIZE	0x04
+#define JEDEC_RES_INSIZE	0x01
+
 /* Write Enable */
 #define JEDEC_WREN		0x06
 #define JEDEC_WREN_OUTSIZE	0x01