| Message ID | c29c928e1473a68fc57dc0ce7a60cf38273d5287.1524432236.git.davidjulianveenstra@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, 23 Apr 2018 00:04:24 +0200 David Veenstra <davidjulianveenstra@gmail.com> wrote: > 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@gmail.com> Good, will pick up with the precursors in v4. Thanks, Jonathan > --- > 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, -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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,
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@gmail.com> --- 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(+)