staging: iio: cdc: ad7746: Push handling of supply voltage scale to userspace.

The supply voltage is attenuated by 6 before being fed to the ADC.
Handle this explicitly rather than pre-multiplying the _raw value by 6.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20220626122938.582107-5-jic23@kernel.org

diff --git a/drivers/staging/iio/cdc/ad7746.c b/drivers/staging/iio/cdc/ad7746.c
index 08f73be5797ac80ac0b306f1b235d71c4edf3a5c..0b5cb788abee76eca48d8c9a4dfeef7e6dccdff2 100644 (file)
--- a/drivers/staging/iio/cdc/ad7746.c
+++ b/drivers/staging/iio/cdc/ad7746.c
@@ -116,9 +116,8 @@ static const struct iio_chan_spec ad7746_channels[] = {
                .type = IIO_VOLTAGE,
                .indexed = 1,
                .channel = 0,
-               .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
-               .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |
-                       BIT(IIO_CHAN_INFO_SAMP_FREQ),
+               .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
+               .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ),
                .address = AD7746_REG_VT_DATA_HIGH << 8 |
                        AD7746_VTSETUP_VTMD_EXT_VIN,
        },
@@ -127,9 +126,8 @@ static const struct iio_chan_spec ad7746_channels[] = {
                .indexed = 1,
                .channel = 1,
                .extend_name = "supply",
-               .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
-               .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |
-                       BIT(IIO_CHAN_INFO_SAMP_FREQ),
+               .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
+               .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ),
                .address = AD7746_REG_VT_DATA_HIGH << 8 |
                        AD7746_VTSETUP_VTMD_VDD_MON,
        },
@@ -562,10 +560,6 @@ static int ad7746_read_raw(struct iio_dev *indio_dev,
                         */
                        *val = (*val * 125) / 256;
                        break;
-               case IIO_VOLTAGE:
-                       if (chan->channel == 1) /* supply_raw*/
-                               *val = *val * 6;
-                       break;
                default:
                        break;
                }
@@ -620,6 +614,8 @@ static int ad7746_read_raw(struct iio_dev *indio_dev,
                case IIO_VOLTAGE:
                        /* 1170mV / 2^23 */
                        *val = 1170;
+                       if (chan->channel == 1)
+                               *val *= 6;
                        *val2 = 23;
                        ret = IIO_VAL_FRACTIONAL_LOG2;
                        break;