A scaling factor of approximately 2 * Pi / (2^12 -1) is added,
to scale the 12-bits angular position to radians.
A return type of IIO_VAL_INT_PLUS_NANO is used, so that the scale of
both the angle channel and angular velocity channel has 7 significant
digits.
Signed-off-by: David Veenstra <davidjulianveenstra@xxxxxxxxx>
---
Changes in v3:
- A decimal approximation of the scale is used, instead
of a fractional approximation.
- Remove unneeded explanation of iio_convert_raw_to_processed.
drivers/staging/iio/resolver/ad2s1200.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/staging/iio/resolver/ad2s1200.c b/drivers/staging/iio/resolver/ad2s1200.c
index 3e1696e52c38..d2b62308b31d 100644
--- a/drivers/staging/iio/resolver/ad2s1200.c
+++ b/drivers/staging/iio/resolver/ad2s1200.c
@@ -60,6 +60,11 @@ static int ad2s1200_read_raw(struct iio_dev *indio_dev,
switch (m) {
case IIO_CHAN_INFO_SCALE:
switch (chan->type) {
+ case IIO_ANGL:
+ /* 2 * Pi / (2^12 - 1) ~= 0.001534355 */
+ *val = 0;
+ *val2 = 1534355;
+ return IIO_VAL_INT_PLUS_NANO;
case IIO_ANGL_VEL:
/* 2 * Pi ~= 6.283185 */
*val = 6;
@@ -114,6 +119,7 @@ static const struct iio_chan_spec ad2s1200_channels[] = {
.indexed = 1,
.channel = 0,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
}, {
.type = IIO_ANGL_VEL,
.indexed = 1,
--
2.16.2
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