diff --git a/hw/i2c/smbus_eeprom.c b/hw/i2c/smbus_eeprom.c
index 76f0d4aab0..3fbbffb4de 100644
--- a/hw/i2c/smbus_eeprom.c
+++ b/hw/i2c/smbus_eeprom.c
@@ -37,6 +37,8 @@
 #define SMBUS_EEPROM(obj) \
     OBJECT_CHECK(SMBusEEPROMDevice, (obj), TYPE_SMBUS_EEPROM)
 
+#define SMBUS_EEPROM_SIZE 256
+
 typedef struct SMBusEEPROMDevice {
     SMBusDevice smbusdev;
     void *data;
@@ -72,7 +74,7 @@ static int eeprom_write_data(SMBusDevice *dev, uint8_t *buf, uint8_t len)
 
     for (; len > 0; len--) {
         data[eeprom->offset] = *buf++;
-        eeprom->offset = (eeprom->offset + 1) % 256;
+        eeprom->offset = (eeprom->offset + 1) % SMBUS_EEPROM_SIZE;
     }
 
     return 0;
@@ -131,13 +133,15 @@ void smbus_eeprom_init(I2CBus *smbus, int nb_eeprom,
                        const uint8_t *eeprom_spd, int eeprom_spd_size)
 {
     int i;
-    uint8_t *eeprom_buf = g_malloc0(8 * 256); /* XXX: make this persistent */
+     /* XXX: make this persistent */
+    uint8_t *eeprom_buf = g_malloc0(8 * SMBUS_EEPROM_SIZE);
     if (eeprom_spd_size > 0) {
         memcpy(eeprom_buf, eeprom_spd, eeprom_spd_size);
     }
 
     for (i = 0; i < nb_eeprom; i++) {
-        smbus_eeprom_init_one(smbus, 0x50 + i, eeprom_buf + (i * 256));
+        smbus_eeprom_init_one(smbus, 0x50 + i,
+                              eeprom_buf + (i * SMBUS_EEPROM_SIZE));
     }
 }