From f9db7370be0e93ce4264781e1ada631a32a61e9b Mon Sep 17 00:00:00 2001 From: David Veenstra Date: Fri, 18 May 2018 20:23:14 +0200 Subject: [PATCH] staging: iio: ad2s1200: Add scaling factor for angle channel 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 Signed-off-by: Jonathan Cameron --- 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 7b8af55..10d6d79 100644 --- a/drivers/staging/iio/resolver/ad2s1200.c +++ b/drivers/staging/iio/resolver/ad2s1200.c @@ -58,6 +58,11 @@ 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; @@ -112,6 +117,7 @@ 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, -- 2.7.4