hwmon: (adt7475) Make adt7475_read_word() return errors

The adt7475_read_word() function was meant to return negative error
codes on failure.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Tokunori Ikegami <ikegami@allied-telesis.co.jp>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
diff --git a/drivers/hwmon/adt7475.c b/drivers/hwmon/adt7475.c
index 1604514..f4c7516 100644
--- a/drivers/hwmon/adt7475.c
+++ b/drivers/hwmon/adt7475.c
@@ -302,14 +302,18 @@
 	return clamp_val(reg, 0, 1023) & (0xff << 2);
 }
 
-static u16 adt7475_read_word(struct i2c_client *client, int reg)
+static int adt7475_read_word(struct i2c_client *client, int reg)
 {
-	u16 val;
+	int val1, val2;
 
-	val = i2c_smbus_read_byte_data(client, reg);
-	val |= (i2c_smbus_read_byte_data(client, reg + 1) << 8);
+	val1 = i2c_smbus_read_byte_data(client, reg);
+	if (val1 < 0)
+		return val1;
+	val2 = i2c_smbus_read_byte_data(client, reg + 1);
+	if (val2 < 0)
+		return val2;
 
-	return val;
+	return val1 | (val2 << 8);
 }
 
 static void adt7475_write_word(struct i2c_client *client, int reg, u16 val)