On 13.04.2024 22:10, David Lechner wrote:
On Sat, Apr 13, 2024 at 10:12 AM Alisa-Dariana Roman
<alisadariana@xxxxxxxxx> wrote:
AINCOM should actually be a supply. If present and it has a non-zero
voltage, the pseudo-differential channels are configured as single-ended
with an offset. Otherwise, they are configured as differential channels
between AINx and AINCOM pins.
Signed-off-by: Alisa-Dariana Roman <alisa.roman@xxxxxxxxxx>
---
drivers/iio/adc/ad7192.c | 53 +++++++++++++++++++++++++++++++++++++---
1 file changed, 49 insertions(+), 4 deletions(-)
...
@@ -745,6 +746,9 @@ static int ad7192_read_raw(struct iio_dev *indio_dev,
/* Kelvin to Celsius */
Not related to this patch, but I'm not a fan of the way the
temperature case writes over *val (maybe clean that up using a switch
statement instead in another patch while we are working on this?).
Adding the else if to this makes it even harder to follow.
if (chan->type == IIO_TEMP)
*val -= 273 * ad7192_get_temp_scale(unipolar);
+ else if (st->aincom_mv && chan->channel2 == -1)
I think the logic should be !chan->differential instead of
chan->channel2 = -1 (more explanation on this below).
+ *val += DIV_ROUND_CLOSEST_ULL((u64)st->aincom_mv * 1000000000,
+ st->scale_avail[gain][1]);
return IIO_VAL_INT;
Hi David,
I am very grateful for your suggestions!
case IIO_CHAN_INFO_OFFSET:
if (!unipolar)
*val = -(1 << (chan->scan_type.realbits - 1));
else
*val = 0;
switch(chan->type) {
case IIO_VOLTAGE:
if (st->aincom_mv && !chan->differential)
*val += DIV_ROUND_CLOSEST_ULL((u64)st->aincom_mv * 1000000000,
st->scale_avail[gain][1]);
return IIO_VAL_INT;
/* Kelvin to Celsius */
case IIO_TEMP:
*val -= 273 * ad7192_get_temp_scale(unipolar);
return IIO_VAL_INT;
default:
return -EINVAL;
}
I added a switch because it looks neater indeed. But I would keep the if
else for the unipolar in order not to have duplicate code. Is this alright?
