hwmon: (ina2xx) Fix word size register read and write operations

The driver uses be16_to_cpu and cpu_to_be16 to convert data in SMBus word
operations from chip to host byte order. However, the data passed from and to
the SMBus word API functions is in host byte order, not in chip byte order.
Conversion should therefore use swab16 instead of be16 to change the byte order.

Replace driver internal word conversion functions with SMBus API functions to
solve the problem.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: stable@vger.kernel.org # 3.5+
Acked-by: Jean Delvare <khali@linux-fr.org>

drivers/hwmon/ina2xx.c

@@ -69,22 +69,6 @@ struct ina2xx_data {
 	u16 regs[INA2XX_MAX_REGISTERS];
 };
 
-int ina2xx_read_word(struct i2c_client *client, int reg)
-{
-	int val = i2c_smbus_read_word_data(client, reg);
-	if (unlikely(val < 0)) {
-		dev_dbg(&client->dev,
-			"Failed to read register: %d\n", reg);
-		return val;
-	}
-	return be16_to_cpu(val);
-}
-
-void ina2xx_write_word(struct i2c_client *client, int reg, int data)
-{
-	i2c_smbus_write_word_data(client, reg, cpu_to_be16(data));
-}
-
 static struct ina2xx_data *ina2xx_update_device(struct device *dev)
 {
 	struct i2c_client *client = to_i2c_client(dev);
@@ -102,7 +86,7 @@ static struct ina2xx_data *ina2xx_update_device(struct device *dev)
 
 		/* Read all registers */
 		for (i = 0; i < data->registers; i++) {
-			int rv = ina2xx_read_word(client, i);
+			int rv = i2c_smbus_read_word_swapped(client, i);
 			if (rv < 0) {
 				ret = ERR_PTR(rv);
 				goto abort;
@@ -279,22 +263,26 @@ static int ina2xx_probe(struct i2c_client *client,
 	switch (data->kind) {
 	case ina219:
 		/* device configuration */
-		ina2xx_write_word(client, INA2XX_CONFIG, INA219_CONFIG_DEFAULT);
+		i2c_smbus_write_word_swapped(client, INA2XX_CONFIG,
+					     INA219_CONFIG_DEFAULT);
 
 		/* set current LSB to 1mA, shunt is in uOhms */
 		/* (equation 13 in datasheet) */
-		ina2xx_write_word(client, INA2XX_CALIBRATION, 40960000 / shunt);
+		i2c_smbus_write_word_swapped(client, INA2XX_CALIBRATION,
+					     40960000 / shunt);
 		dev_info(&client->dev,
 			 "power monitor INA219 (Rshunt = %li uOhm)\n", shunt);
 		data->registers = INA219_REGISTERS;
 		break;
 	case ina226:
 		/* device configuration */
-		ina2xx_write_word(client, INA2XX_CONFIG, INA226_CONFIG_DEFAULT);
+		i2c_smbus_write_word_swapped(client, INA2XX_CONFIG,
+					     INA226_CONFIG_DEFAULT);
 
 		/* set current LSB to 1mA, shunt is in uOhms */
 		/* (equation 1 in datasheet)*/
-		ina2xx_write_word(client, INA2XX_CALIBRATION, 5120000 / shunt);
+		i2c_smbus_write_word_swapped(client, INA2XX_CALIBRATION,
+					     5120000 / shunt);
 		dev_info(&client->dev,
 			 "power monitor INA226 (Rshunt = %li uOhm)\n", shunt);
 		data->registers = INA226_REGISTERS;