staging:iio:cdc:ad7150: Add scale and offset to info_mask_shared_by_type

The datasheet provides these two values on the assumption they are applied
to unshift raw value.  Hence shift both the offset and scale by 4
to compensate.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20210314181511.531414-19-jic23@kernel.org
This commit is contained in:
Jonathan Cameron 2021-03-14 18:15:05 +00:00
parent f28334febd
commit 18595e71c5

View file

@ -121,6 +121,18 @@ static int ad7150_read_raw(struct iio_dev *indio_dev,
return ret;
*val = ret;
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
/*
* Base units for capacitance are nano farads and the value
* calculated from the datasheet formula is in picofarad
* so multiply by 1000
*/
*val = 1000;
*val2 = 40944 >> 4; /* To match shift in _RAW */
return IIO_VAL_FRACTIONAL;
case IIO_CHAN_INFO_OFFSET:
*val = -(12288 >> 4); /* To match shift in _RAW */
return IIO_VAL_INT;
case IIO_CHAN_INFO_SAMP_FREQ:
/* Strangely same for both 1 and 2 chan parts */
@ -425,6 +437,8 @@ static const struct iio_event_spec ad7150_events[] = {
.channel = _chan, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
BIT(IIO_CHAN_INFO_AVERAGE_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
BIT(IIO_CHAN_INFO_OFFSET), \
.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\
.event_spec = ad7150_events, \
.num_event_specs = ARRAY_SIZE(ad7150_events), \
@ -436,6 +450,8 @@ static const struct iio_event_spec ad7150_events[] = {
.channel = _chan, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
BIT(IIO_CHAN_INFO_AVERAGE_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
BIT(IIO_CHAN_INFO_OFFSET), \
.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\
}