From 4623b414e68bb57ce30fe286ca932202fc438a16 Mon Sep 17 00:00:00 2001 From: David Lechner Date: Fri, 29 Sep 2023 12:23:13 -0500 Subject: staging: iio: resolver: ad2s1210: implement IIO_CHAN_INFO_SCALE This adds an implementation of IIO_CHAN_INFO_SCALE to the ad2s1210 resolver driver. This allows userspace to get the scale factor for the raw values. Signed-off-by: David Lechner Link: https://lore.kernel.org/r/20230929-ad2s1210-mainline-v3-8-fa4364281745@baylibre.com Signed-off-by: Jonathan Cameron --- drivers/staging/iio/resolver/ad2s1210.c | 53 ++++++++++++++++++++++++++++----- 1 file changed, 45 insertions(+), 8 deletions(-) (limited to 'drivers/staging/iio/resolver/ad2s1210.c') diff --git a/drivers/staging/iio/resolver/ad2s1210.c b/drivers/staging/iio/resolver/ad2s1210.c index f9774dff2df4..a710598a64f0 100644 --- a/drivers/staging/iio/resolver/ad2s1210.c +++ b/drivers/staging/iio/resolver/ad2s1210.c @@ -461,13 +461,10 @@ error_ret: return ret < 0 ? ret : len; } -static int ad2s1210_read_raw(struct iio_dev *indio_dev, - struct iio_chan_spec const *chan, - int *val, - int *val2, - long m) +static int ad2s1210_single_conversion(struct ad2s1210_state *st, + struct iio_chan_spec const *chan, + int *val) { - struct ad2s1210_state *st = iio_priv(indio_dev); int ret = 0; mutex_lock(&st->lock); @@ -514,6 +511,44 @@ error_ret: return ret; } +static const int ad2s1210_velocity_scale[] = { + 17089132, /* 8.192MHz / (2*pi * 2500 / 2^15) */ + 42722830, /* 8.192MHz / (2*pi * 1000 / 2^15) */ + 85445659, /* 8.192MHz / (2*pi * 500 / 2^15) */ + 341782638, /* 8.192MHz / (2*pi * 125 / 2^15) */ +}; + +static int ad2s1210_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, + int *val2, + long mask) +{ + struct ad2s1210_state *st = iio_priv(indio_dev); + + switch (mask) { + case IIO_CHAN_INFO_RAW: + return ad2s1210_single_conversion(st, chan, val); + case IIO_CHAN_INFO_SCALE: + switch (chan->type) { + case IIO_ANGL: + /* approx 0.3 arc min converted to radians */ + *val = 0; + *val2 = 95874; + return IIO_VAL_INT_PLUS_NANO; + case IIO_ANGL_VEL: + *val = st->fclkin; + *val2 = ad2s1210_velocity_scale[st->resolution]; + return IIO_VAL_FRACTIONAL; + default: + return -EINVAL; + } + + default: + return -EINVAL; + } +} + static IIO_DEVICE_ATTR(fclkin, 0644, ad2s1210_show_fclkin, ad2s1210_store_fclkin, 0); static IIO_DEVICE_ATTR(fexcit, 0644, @@ -552,12 +587,14 @@ static const struct iio_chan_spec ad2s1210_channels[] = { .type = IIO_ANGL, .indexed = 1, .channel = 0, - .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE), }, { .type = IIO_ANGL_VEL, .indexed = 1, .channel = 0, - .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE), } }; -- cgit v1.2.3