[PATCH v1 1/3] iio: afe: rescale: Move scale conversion to new function

From: MylÃne Josserand
Date: Tue Jun 11 2019 - 06:01:58 EST


To prepare the support of processed value, create a function
to convert the scale according to the voltage-divider node
used in the device-tree.

Signed-off-by: MylÃne Josserand <mylene.josserand@xxxxxxxxxxx>
---
drivers/iio/afe/iio-rescale.c | 54 +++++++++++++++++++++++++------------------
1 file changed, 31 insertions(+), 23 deletions(-)

diff --git a/drivers/iio/afe/iio-rescale.c b/drivers/iio/afe/iio-rescale.c
index e9ceee66d1e7..3e689d6eb501 100644
--- a/drivers/iio/afe/iio-rescale.c
+++ b/drivers/iio/afe/iio-rescale.c
@@ -33,12 +33,41 @@ struct rescale {
s32 denominator;
};

+static int rescale_convert_scale(struct rescale *rescale, int *val, int *val2)
+{
+ unsigned long long tmp;
+ int ret;
+
+ ret = iio_read_channel_scale(rescale->source, val, val2);
+ switch (ret) {
+ case IIO_VAL_FRACTIONAL:
+ *val *= rescale->numerator;
+ *val2 *= rescale->denominator;
+ return ret;
+ case IIO_VAL_INT:
+ *val *= rescale->numerator;
+ if (rescale->denominator == 1)
+ return ret;
+ *val2 = rescale->denominator;
+ return IIO_VAL_FRACTIONAL;
+ case IIO_VAL_FRACTIONAL_LOG2:
+ tmp = *val * 1000000000LL;
+ do_div(tmp, rescale->denominator);
+ tmp *= rescale->numerator;
+ do_div(tmp, 1000000000LL);
+ *val = tmp;
+
+ return ret;
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
static int rescale_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct rescale *rescale = iio_priv(indio_dev);
- unsigned long long tmp;
int ret;

switch (mask) {
@@ -46,28 +75,7 @@ static int rescale_read_raw(struct iio_dev *indio_dev,
return iio_read_channel_raw(rescale->source, val);

case IIO_CHAN_INFO_SCALE:
- ret = iio_read_channel_scale(rescale->source, val, val2);
- switch (ret) {
- case IIO_VAL_FRACTIONAL:
- *val *= rescale->numerator;
- *val2 *= rescale->denominator;
- return ret;
- case IIO_VAL_INT:
- *val *= rescale->numerator;
- if (rescale->denominator == 1)
- return ret;
- *val2 = rescale->denominator;
- return IIO_VAL_FRACTIONAL;
- case IIO_VAL_FRACTIONAL_LOG2:
- tmp = *val * 1000000000LL;
- do_div(tmp, rescale->denominator);
- tmp *= rescale->numerator;
- do_div(tmp, 1000000000LL);
- *val = tmp;
- return ret;
- default:
- return -EOPNOTSUPP;
- }
+ return rescale_convert_scale(rescale, val, val2);
default:
return -EINVAL;
}
--
2.11.0