In bipolar mode there is a a binary offset of 2**(N-1) (with N being the number of bits) on the reported value. Currently this value is subtracted when doing a manual read. While this works for manual channel readings it does not work for buffered mode. So report the offset in the channels offset property, which will work in both modes. Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx> --- drivers/staging/iio/adc/ad7793.c | 39 +++++++++++++++++++++++++------------- 1 file changed, 26 insertions(+), 13 deletions(-) diff --git a/drivers/staging/iio/adc/ad7793.c b/drivers/staging/iio/adc/ad7793.c index 5e457a4..56014a8 100644 --- a/drivers/staging/iio/adc/ad7793.c +++ b/drivers/staging/iio/adc/ad7793.c @@ -604,9 +604,6 @@ static int ad7793_read_raw(struct iio_dev *indio_dev, *val = (smpl >> chan->scan_type.shift) & ((1 << (chan->scan_type.realbits)) - 1); - if (!unipolar) - *val -= (1 << (chan->scan_type.realbits - 1)); - return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: @@ -639,6 +636,12 @@ static int ad7793_read_raw(struct iio_dev *indio_dev, *val = scale_uv; return IIO_VAL_INT_PLUS_NANO; + case IIO_CHAN_INFO_OFFSET: + if (!unipolar) + *val -= (1 << (chan->scan_type.realbits - 1)); + else + *val = 0; + return IIO_VAL_INT; } return -EINVAL; } @@ -720,7 +723,8 @@ static const struct ad7793_chip_info ad7793_chip_info_tbl[] = { .channel2 = 0, .address = AD7793_CH_AIN1P_AIN1M, .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | - IIO_CHAN_INFO_SCALE_SHARED_BIT, + IIO_CHAN_INFO_SCALE_SHARED_BIT | + IIO_CHAN_INFO_OFFSET_SHARED_BIT, .scan_index = 0, .scan_type = IIO_ST('u', 24, 32, 0) }, @@ -732,7 +736,8 @@ static const struct ad7793_chip_info ad7793_chip_info_tbl[] = { .channel2 = 1, .address = AD7793_CH_AIN2P_AIN2M, .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | - IIO_CHAN_INFO_SCALE_SHARED_BIT, + IIO_CHAN_INFO_SCALE_SHARED_BIT | + IIO_CHAN_INFO_OFFSET_SHARED_BIT, .scan_index = 1, .scan_type = IIO_ST('u', 24, 32, 0) }, @@ -744,7 +749,8 @@ static const struct ad7793_chip_info ad7793_chip_info_tbl[] = { .channel2 = 2, .address = AD7793_CH_AIN3P_AIN3M, .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | - IIO_CHAN_INFO_SCALE_SHARED_BIT, + IIO_CHAN_INFO_SCALE_SHARED_BIT | + IIO_CHAN_INFO_OFFSET_SHARED_BIT, .scan_index = 2, .scan_type = IIO_ST('u', 24, 32, 0) }, @@ -757,7 +763,8 @@ static const struct ad7793_chip_info ad7793_chip_info_tbl[] = { .channel2 = 2, .address = AD7793_CH_AIN1M_AIN1M, .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | - IIO_CHAN_INFO_SCALE_SHARED_BIT, + IIO_CHAN_INFO_SCALE_SHARED_BIT | + IIO_CHAN_INFO_OFFSET_SHARED_BIT, .scan_index = 3, .scan_type = IIO_ST('u', 24, 32, 0) }, @@ -778,7 +785,8 @@ static const struct ad7793_chip_info ad7793_chip_info_tbl[] = { .channel = 4, .address = AD7793_CH_AVDD_MONITOR, .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | - IIO_CHAN_INFO_SCALE_SEPARATE_BIT, + IIO_CHAN_INFO_SCALE_SEPARATE_BIT | + IIO_CHAN_INFO_OFFSET_SHARED_BIT, .scan_index = 5, .scan_type = IIO_ST('u', 24, 32, 0), }, @@ -793,7 +801,8 @@ static const struct ad7793_chip_info ad7793_chip_info_tbl[] = { .channel2 = 0, .address = AD7793_CH_AIN1P_AIN1M, .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | - IIO_CHAN_INFO_SCALE_SHARED_BIT, + IIO_CHAN_INFO_SCALE_SHARED_BIT | + IIO_CHAN_INFO_OFFSET_SHARED_BIT, .scan_index = 0, .scan_type = IIO_ST('u', 16, 32, 0) }, @@ -805,7 +814,8 @@ static const struct ad7793_chip_info ad7793_chip_info_tbl[] = { .channel2 = 1, .address = AD7793_CH_AIN2P_AIN2M, .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | - IIO_CHAN_INFO_SCALE_SHARED_BIT, + IIO_CHAN_INFO_SCALE_SHARED_BIT | + IIO_CHAN_INFO_OFFSET_SHARED_BIT, .scan_index = 1, .scan_type = IIO_ST('u', 16, 32, 0) }, @@ -817,7 +827,8 @@ static const struct ad7793_chip_info ad7793_chip_info_tbl[] = { .channel2 = 2, .address = AD7793_CH_AIN3P_AIN3M, .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | - IIO_CHAN_INFO_SCALE_SHARED_BIT, + IIO_CHAN_INFO_SCALE_SHARED_BIT | + IIO_CHAN_INFO_OFFSET_SHARED_BIT, .scan_index = 2, .scan_type = IIO_ST('u', 16, 32, 0) }, @@ -830,7 +841,8 @@ static const struct ad7793_chip_info ad7793_chip_info_tbl[] = { .channel2 = 2, .address = AD7793_CH_AIN1M_AIN1M, .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | - IIO_CHAN_INFO_SCALE_SHARED_BIT, + IIO_CHAN_INFO_SCALE_SHARED_BIT | + IIO_CHAN_INFO_OFFSET_SHARED_BIT, .scan_index = 3, .scan_type = IIO_ST('u', 16, 32, 0) }, @@ -851,7 +863,8 @@ static const struct ad7793_chip_info ad7793_chip_info_tbl[] = { .channel = 4, .address = AD7793_CH_AVDD_MONITOR, .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | - IIO_CHAN_INFO_SCALE_SEPARATE_BIT, + IIO_CHAN_INFO_SCALE_SEPARATE_BIT | + IIO_CHAN_INFO_OFFSET_SHARED_BIT, .scan_index = 5, .scan_type = IIO_ST('u', 16, 32, 0), }, -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html