iio: magnetometer: ak8975: reduce usage of magic lengths of the buffer

Reduce usage of magic lengths of the supplied buffer by replacing them
with the corresponding sizeof():s.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Joshua Crofts <joshua.crofts1@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Author: andy-shev

drivers/iio/magnetometer/ak8975.c

@@ -489,8 +489,10 @@ static int ak8975_who_i_am(struct i2c_client *client,
 	 * AK8975   |  DEVICE_ID |  NA
 	 * AK8963   |  DEVICE_ID |  NA
 	 */
-	ret = i2c_smbus_read_i2c_block_data_or_emulated(
-			client, AK09912_REG_WIA1, 2, wia_val);
+	ret = i2c_smbus_read_i2c_block_data_or_emulated(client,
+							AK09912_REG_WIA1,
+							sizeof(wia_val),
+							wia_val);
 	if (ret < 0) {
 		dev_err(&client->dev, "Error reading WIA\n");
 		return ret;
@@ -609,9 +611,10 @@ static int ak8975_setup(struct i2c_client *client)
 	}
 
 	/* Get asa data and store in the device data. */
-	ret = i2c_smbus_read_i2c_block_data_or_emulated(
-			client, data->def->ctrl_regs[ASA_BASE],
-			3, data->asa);
+	ret = i2c_smbus_read_i2c_block_data_or_emulated(client,
+							data->def->ctrl_regs[ASA_BASE],
+							sizeof(data->asa),
+							data->asa);
 	if (ret < 0) {
 		dev_err(&client->dev, "Not able to read asa data\n");
 		return ret;
@@ -866,7 +869,7 @@ static void ak8975_fill_buffer(struct iio_dev *indio_dev)
 	 */
 	ret = i2c_smbus_read_i2c_block_data_or_emulated(client,
 							def->data_regs[0],
-							3 * sizeof(fval[0]),
+							sizeof(fval),
 							(u8 *)fval);
 	if (ret < 0)
 		goto unlock;