diff --git a/drivers/mfd/twl-core.c b/drivers/mfd/twl-core.c
index d666c9d454cb..bb33b52cfa57 100644
--- a/drivers/mfd/twl-core.c
+++ b/drivers/mfd/twl-core.c
@@ -66,9 +66,6 @@
 
 /* Triton Core internal information (BEGIN) */
 
-/* Last - for index max*/
-#define TWL4030_MODULE_LAST		TWL4030_MODULE_SECURED_REG
-
 #define TWL_NUM_SLAVES		4
 
 #define SUB_CHIP_ID0 0
@@ -184,7 +181,7 @@ struct twl_mapping {
 };
 static struct twl_mapping *twl_map;
 
-static struct twl_mapping twl4030_map[TWL4030_MODULE_LAST + 1] = {
+static struct twl_mapping twl4030_map[] = {
 	/*
 	 * NOTE:  don't change this table without updating the
 	 * <linux/i2c/twl.h> defines for TWL4030_MODULE_*
@@ -327,7 +324,7 @@ int twl_i2c_write(u8 mod_no, u8 *value, u8 reg, unsigned num_bytes)
 	int sid;
 	struct twl_client *twl;
 
-	if (unlikely(mod_no > TWL_MODULE_LAST)) {
+	if (unlikely(mod_no >= TWL_MODULE_LAST)) {
 		pr_err("%s: invalid module number %d\n", DRIVER_NAME, mod_no);
 		return -EPERM;
 	}
@@ -369,7 +366,7 @@ int twl_i2c_read(u8 mod_no, u8 *value, u8 reg, unsigned num_bytes)
 	int sid;
 	struct twl_client *twl;
 
-	if (unlikely(mod_no > TWL_MODULE_LAST)) {
+	if (unlikely(mod_no >= TWL_MODULE_LAST)) {
 		pr_err("%s: invalid module number %d\n", DRIVER_NAME, mod_no);
 		return -EPERM;
 	}
diff --git a/include/linux/i2c/twl.h b/include/linux/i2c/twl.h
index 7278c72479d1..b1c44cccef31 100644
--- a/include/linux/i2c/twl.h
+++ b/include/linux/i2c/twl.h
@@ -39,39 +39,39 @@
  * address each module uses within a given i2c slave.
  */
 
-/* Slave 0 (i2c address 0x48) */
-#define TWL4030_MODULE_USB		0x00
+enum twl4030_module_ids {
+	TWL4030_MODULE_USB = 0,		/* Slave 0 (i2c address 0x48) */
+	TWL4030_MODULE_AUDIO_VOICE,	/* Slave 1 (i2c address 0x49) */
+	TWL4030_MODULE_GPIO,
+	TWL4030_MODULE_INTBR,
+	TWL4030_MODULE_PIH,
 
-/* Slave 1 (i2c address 0x49) */
-#define TWL4030_MODULE_AUDIO_VOICE	0x01
-#define TWL4030_MODULE_GPIO		0x02
-#define TWL4030_MODULE_INTBR		0x03
-#define TWL4030_MODULE_PIH		0x04
-#define TWL4030_MODULE_TEST		0x05
+	TWL4030_MODULE_TEST,
+	TWL4030_MODULE_KEYPAD,		/* Slave 2 (i2c address 0x4a) */
+	TWL4030_MODULE_MADC,
+	TWL4030_MODULE_INTERRUPTS,
+	TWL4030_MODULE_LED,
 
-/* Slave 2 (i2c address 0x4a) */
-#define TWL4030_MODULE_KEYPAD		0x06
-#define TWL4030_MODULE_MADC		0x07
-#define TWL4030_MODULE_INTERRUPTS	0x08
-#define TWL4030_MODULE_LED		0x09
-#define TWL4030_MODULE_MAIN_CHARGE	0x0A
-#define TWL4030_MODULE_PRECHARGE	0x0B
-#define TWL4030_MODULE_PWM0		0x0C
-#define TWL4030_MODULE_PWM1		0x0D
-#define TWL4030_MODULE_PWMA		0x0E
-#define TWL4030_MODULE_PWMB		0x0F
+	TWL4030_MODULE_MAIN_CHARGE,
+	TWL4030_MODULE_PRECHARGE,
+	TWL4030_MODULE_PWM0,
+	TWL4030_MODULE_PWM1,
+	TWL4030_MODULE_PWMA,
 
-#define TWL5031_MODULE_ACCESSORY	0x10
-#define TWL5031_MODULE_INTERRUPTS	0x11
+	TWL4030_MODULE_PWMB,
+	TWL5031_MODULE_ACCESSORY,
+	TWL5031_MODULE_INTERRUPTS,
+	TWL4030_MODULE_BACKUP,		/* Slave 3 (i2c address 0x4b) */
+	TWL4030_MODULE_INT,
 
-/* Slave 3 (i2c address 0x4b) */
-#define TWL4030_MODULE_BACKUP		0x12
-#define TWL4030_MODULE_INT		0x13
-#define TWL4030_MODULE_PM_MASTER	0x14
-#define TWL4030_MODULE_PM_RECEIVER	0x15
-#define TWL4030_MODULE_RTC		0x16
-#define TWL4030_MODULE_SECURED_REG	0x17
+	TWL4030_MODULE_PM_MASTER,
+	TWL4030_MODULE_PM_RECEIVER,
+	TWL4030_MODULE_RTC,
+	TWL4030_MODULE_SECURED_REG,
+	TWL4030_MODULE_LAST,
+};
 
+/* Similar functionalities implemented in TWL4030/6030 */
 #define TWL_MODULE_USB		TWL4030_MODULE_USB
 #define TWL_MODULE_PIH		TWL4030_MODULE_PIH
 #define TWL_MODULE_MAIN_CHARGE	TWL4030_MODULE_MAIN_CHARGE
@@ -79,6 +79,7 @@
 #define TWL_MODULE_PM_RECEIVER	TWL4030_MODULE_PM_RECEIVER
 #define TWL_MODULE_RTC		TWL4030_MODULE_RTC
 #define TWL_MODULE_PWM		TWL4030_MODULE_PWM0
+#define TWL_MODULE_LED		TWL4030_MODULE_LED
 
 #define TWL6030_MODULE_ID0	0x0D
 #define TWL6030_MODULE_ID1	0x0E