diff --git a/drivers/mtd/spi/sf_internal.h b/drivers/mtd/spi/sf_internal.h
index 70ea4b0..9642265 100644
--- a/drivers/mtd/spi/sf_internal.h
+++ b/drivers/mtd/spi/sf_internal.h
@@ -107,6 +107,7 @@ int sst_write_bp(struct spi_flash *flash, u32 offset, size_t len,
 #define JEDEC_MFR(info)		((info)->id[0])
 #define JEDEC_ID(info)		(((info)->id[1]) << 8 | ((info)->id[2]))
 #define JEDEC_EXT(info)		(((info)->id[3]) << 8 | ((info)->id[4]))
+#define SPI_FLASH_MAX_ID_LEN	5
 
 struct spi_flash_info {
 	/* Device name ([MANUFLETTER][DEVTYPE][DENSITY][EXTRAINFO]) */
@@ -117,7 +118,7 @@ struct spi_flash_info {
 	 * The first three bytes are the JEDIC ID.
 	 * JEDEC ID zero means "no ID" (mostly older chips).
 	 */
-	u8		id[5];
+	u8		id[SPI_FLASH_MAX_ID_LEN];
 	u8		id_len;
 
 	/*
diff --git a/drivers/mtd/spi/spi_flash.c b/drivers/mtd/spi/spi_flash.c
index f7634df..9430424 100644
--- a/drivers/mtd/spi/spi_flash.c
+++ b/drivers/mtd/spi/spi_flash.c
@@ -928,10 +928,10 @@ static int micron_quad_enable(struct spi_flash *flash)
 static const struct spi_flash_info *spi_flash_read_id(struct spi_flash *flash)
 {
 	int				tmp;
-	u8				id[5];
+	u8				id[SPI_FLASH_MAX_ID_LEN];
 	const struct spi_flash_info	*info;
 
-	tmp = spi_flash_cmd(flash->spi, CMD_READ_ID, id, 5);
+	tmp = spi_flash_cmd(flash->spi, CMD_READ_ID, id, SPI_FLASH_MAX_ID_LEN);
 	if (tmp < 0) {
 		printf("SF: error %d reading JEDEC ID\n", tmp);
 		return ERR_PTR(tmp);