diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 45e2cdf5473..a45155f799d 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -916,7 +916,7 @@ s32 i2c_smbus_write_word_data(struct i2c_client *client, u8 command, u16 value)
 }
 
 s32 i2c_smbus_write_block_data(struct i2c_client *client, u8 command,
-			       u8 length, u8 *values)
+			       u8 length, const u8 *values)
 {
 	union i2c_smbus_data data;
 
@@ -944,7 +944,7 @@ s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client, u8 command, u8 *val
 }
 
 s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client, u8 command,
-				   u8 length, u8 *values)
+				   u8 length, const u8 *values)
 {
 	union i2c_smbus_data data;
 
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 0510430e00d..526ddc8eecf 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -97,13 +97,13 @@ extern s32 i2c_smbus_write_word_data(struct i2c_client * client,
                                      u8 command, u16 value);
 extern s32 i2c_smbus_write_block_data(struct i2c_client * client,
 				      u8 command, u8 length,
-				      u8 *values);
+				      const u8 *values);
 /* Returns the number of read bytes */
 extern s32 i2c_smbus_read_i2c_block_data(struct i2c_client * client,
 					 u8 command, u8 *values);
 extern s32 i2c_smbus_write_i2c_block_data(struct i2c_client * client,
 					  u8 command, u8 length,
-					  u8 *values);
+					  const u8 *values);
 
 /*
  * A driver is capable of handling one or more physical devices present on