staging:iio:ad7291: Use sign_extend32 instead of open-coding it

This makes it a bit more obvious what is going on than open-coding it.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/staging/iio/adc/ad7291.c b/drivers/staging/iio/adc/ad7291.c
index 2a7e6a77a46b75c9a95b4bb991ae53c0865b164f..c2709d68af69f9601696f5fe0777fcfc6816015e 100644 (file)
--- a/drivers/staging/iio/adc/ad7291.c
+++ b/drivers/staging/iio/adc/ad7291.c
@@ -275,7 +275,6 @@ static int ad7291_read_event_value(struct iio_dev *indio_dev,
        struct ad7291_chip_info *chip = iio_priv(indio_dev);
        int ret;
        u16 uval;
-       s16 signval;
 
        ret = ad7291_i2c_read(chip, ad7291_threshold_reg(event_code), &uval);
        if (ret < 0)
@@ -286,8 +285,7 @@ static int ad7291_read_event_value(struct iio_dev *indio_dev,
                *val = uval & AD7291_VALUE_MASK;
                return 0;
        case IIO_TEMP:
-               signval = (s16)((uval & AD7291_VALUE_MASK) << 4) >> 4;
-               *val = signval;
+               *val = sign_extend32(uval, 11);
                return 0;
        default:
                return -EINVAL;
@@ -397,7 +395,6 @@ static int ad7291_read_raw(struct iio_dev *indio_dev,
        int ret;
        struct ad7291_chip_info *chip = iio_priv(indio_dev);
        u16 regval;
-       s16 signval;
 
        switch (mask) {
        case IIO_CHAN_INFO_RAW:
@@ -433,8 +430,7 @@ static int ad7291_read_raw(struct iio_dev *indio_dev,
                                                       AD7291_T_SENSE);
                        if (ret < 0)
                                return ret;
-                       signval = (s16)((ret & AD7291_VALUE_MASK) << 4) >> 4;
-                       *val = signval;
+                       *val = sign_extend32(ret, 11);
                        return IIO_VAL_INT;
                default:
                        return -EINVAL;
@@ -444,8 +440,7 @@ static int ad7291_read_raw(struct iio_dev *indio_dev,
                                               AD7291_T_AVERAGE);
                        if (ret < 0)
                                return ret;
-                       signval = (s16)((ret & AD7291_VALUE_MASK) << 4) >> 4;
-                       *val = signval;
+                       *val = sign_extend32(ret, 11);
                        return IIO_VAL_INT;
        case IIO_CHAN_INFO_SCALE:
                switch (chan->type) {