On Sat, Apr 21, 2018 at 9:41 AM, Jonathan Cameron <jic23@xxxxxxxxxx> wrote:
> On Fri, 20 Apr 2018 23:47:30 -0700
> Matt Ranostay <matt.ranostay@xxxxxxxxxxxx> wrote:
>
>> Lookup table was highly dependent on using the LMP91000EVM which had an
>> 16-bit TI ADC161S626 but it is mistake to assume all applications will
>> be using that ADC part. Any processing should be done in the respective
>> userspace application.
>>
>> Signed-off-by: Matt Ranostay <matt.ranostay@xxxxxxxxxxxx>
> Hohum. The problem here is that now, any users that are out there will
> have code based on the conversion done in this table.
Yeah I had a feeling you or someone would comment on that :).
> It should at least be linear (I think) off the back of this table?
> If so we should probably have reported it as raw (as there is an unknown
> scale still to apply) but the table is otherwise valid (I think!)
>
Yeah should have always been reported as raw.
I'll have to think of a better solution, and it may not even be an
issue because we are using iio_convert_raw_to_processed()
on the channel data and it should error out if it can't do it.
- Matt
> Jonathan
>
>> ---
>> drivers/iio/potentiostat/lmp91000.c | 38 ++++---------------------------------
>> 1 file changed, 4 insertions(+), 34 deletions(-)
>>
>> diff --git a/drivers/iio/potentiostat/lmp91000.c b/drivers/iio/potentiostat/lmp91000.c
>> index 85714055cc74..e464f72b144b 100644
>> --- a/drivers/iio/potentiostat/lmp91000.c
>> +++ b/drivers/iio/potentiostat/lmp91000.c
>> @@ -41,21 +41,6 @@ static const int lmp91000_rload[] = { 10, 33, 50, 100 };
>>
>> #define LMP91000_TEMP_BASE -40
>>
>> -static const u16 lmp91000_temp_lut[] = {
>> - 1875, 1867, 1860, 1852, 1844, 1836, 1828, 1821, 1813, 1805,
>> - 1797, 1789, 1782, 1774, 1766, 1758, 1750, 1742, 1734, 1727,
>> - 1719, 1711, 1703, 1695, 1687, 1679, 1671, 1663, 1656, 1648,
>> - 1640, 1632, 1624, 1616, 1608, 1600, 1592, 1584, 1576, 1568,
>> - 1560, 1552, 1544, 1536, 1528, 1520, 1512, 1504, 1496, 1488,
>> - 1480, 1472, 1464, 1456, 1448, 1440, 1432, 1424, 1415, 1407,
>> - 1399, 1391, 1383, 1375, 1367, 1359, 1351, 1342, 1334, 1326,
>> - 1318, 1310, 1302, 1293, 1285, 1277, 1269, 1261, 1253, 1244,
>> - 1236, 1228, 1220, 1212, 1203, 1195, 1187, 1179, 1170, 1162,
>> - 1154, 1146, 1137, 1129, 1121, 1112, 1104, 1096, 1087, 1079,
>> - 1071, 1063, 1054, 1046, 1038, 1029, 1021, 1012, 1004, 996,
>> - 987, 979, 971, 962, 954, 945, 937, 929, 920, 912,
>> - 903, 895, 886, 878, 870, 861 };
>> -
>> static const struct regmap_config lmp91000_regmap_config = {
>> .reg_bits = 8,
>> .val_bits = 8,
>> @@ -95,7 +80,7 @@ static const struct iio_chan_spec lmp91000_channels[] = {
>> .type = IIO_TEMP,
>> .channel = 1,
>> .address = LMP91000_REG_MODECN_TEMP,
>> - .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
>> .scan_index = -1,
>> },
>> };
>> @@ -157,11 +142,11 @@ static int lmp91000_read_raw(struct iio_dev *indio_dev,
>> int *val, int *val2, long mask)
>> {
>> struct lmp91000_data *data = iio_priv(indio_dev);
>> + int ret = -EINVAL;
>>
>> switch (mask) {
>> case IIO_CHAN_INFO_RAW:
>> - case IIO_CHAN_INFO_PROCESSED: {
>> - int ret = iio_channel_start_all_cb(data->cb_buffer);
>> + ret = iio_channel_start_all_cb(data->cb_buffer);
>>
>> if (ret)
>> return ret;
>> @@ -173,29 +158,14 @@ static int lmp91000_read_raw(struct iio_dev *indio_dev,
>> if (ret)
>> return ret;
>>
>> - if (mask == IIO_CHAN_INFO_PROCESSED) {
>> - int tmp, i;
>> -
>> - ret = iio_convert_raw_to_processed(data->adc_chan,
>> - *val, &tmp, 1);
>> - if (ret)
>> - return ret;
>> -
>> - for (i = 0; i < ARRAY_SIZE(lmp91000_temp_lut); i++)
>> - if (lmp91000_temp_lut[i] < tmp)
>> - break;
>> -
>> - *val = (LMP91000_TEMP_BASE + i) * 1000;
>> - }
>> return IIO_VAL_INT;
>> - }
>> case IIO_CHAN_INFO_OFFSET:
>> return iio_read_channel_offset(data->adc_chan, val, val2);
>> case IIO_CHAN_INFO_SCALE:
>> return iio_read_channel_scale(data->adc_chan, val, val2);
>> }
>>
>> - return -EINVAL;
>> + return ret;
>> }
>>
>> static const struct iio_info lmp91000_info = {
>
--
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
