iio: si7020: Swap data byte order
authorChris Lesiak <chris.lesiak@licor.com>
Mon, 2 Nov 2015 21:45:03 +0000 (15:45 -0600)
committerJonathan Cameron <jic23@kernel.org>
Sun, 15 Nov 2015 12:36:19 +0000 (12:36 +0000)
The Silicon Labs Si7013, Si7020, and Si7021 family of I2C humidity and
temperature sensors deliver 16 bit data high byte first.

See the datasheet available at:
https://www.silabs.com/Support%20Documents%2fTechnicalDocs%2fSi7020-A20.pdf

But as documented in Documentation/i2c/smbus-protocol,
i2c_smbus_read_word_data() expects the low byte first.

Change the driver to use i2c_smbus_read_word_swapped to get correct byte
order.

Signed-off-by: Chris Lesiak <chris.lesiak@licor.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
drivers/iio/humidity/si7020.c

index fa3b809aff5efd425ce96031aec1c066b644feb2..1b6935d991006724dd78acc80e7f3f4ec23de799 100644 (file)
@@ -50,10 +50,10 @@ static int si7020_read_raw(struct iio_dev *indio_dev,
 
        switch (mask) {
        case IIO_CHAN_INFO_RAW:
-               ret = i2c_smbus_read_word_data(*client,
-                                              chan->type == IIO_TEMP ?
-                                              SI7020CMD_TEMP_HOLD :
-                                              SI7020CMD_RH_HOLD);
+               ret = i2c_smbus_read_word_swapped(*client,
+                                                 chan->type == IIO_TEMP ?
+                                                 SI7020CMD_TEMP_HOLD :
+                                                 SI7020CMD_RH_HOLD);
                if (ret < 0)
                        return ret;
                *val = ret >> 2;