Hi Ramakrishna,
[snip..]
>>> + u32 i = 0;
>>> +
>>> + if (!pts)
>>> + return -EINVAL;
>>> +
>>> + /* Check if table is descending or ascending */
>>> + if (tablesize > 1) {
>>> + if (pts[0].x < pts[1].x)
>>> + descending = 0;
>>> + }
>>> +
>>> + while (i < tablesize) {
>>> + if ((descending == 1) && (pts[i].x < input)) {
>>
>> Just if (descending) instead of (descending == 1) and so on for the
>> below as well
>
> Will change in next patch.
>
>>
>>> + /* table entry is less than measured*/
>>> + /* value and table is descending, stop */
>>> + break;
>>> + } else if ((descending == 0) &&
>>> + (pts[i].x > input)) {
>>> + /* table entry is greater than measured*/
>>> + /*value and table is ascending, stop */
>>> + break;
>>> + }
>>> + i++;
>>> + }
>>> +
>>> + if (i == 0) {
>>> + *output = pts[0].y;
>>> + } else if (i == tablesize) {
>>> + *output = pts[tablesize - 1].y;
>>> + } else {
>>> + /* result is between search_index and search_index-1 */
>>> + /* interpolate linearly */
>>> + *output = (((s32)((pts[i].y - pts[i - 1].y) *
>>> + (input - pts[i - 1].x)) /
>>> + (pts[i].x - pts[i - 1].x)) +
>>> + pts[i - 1].y);
>>> + }
>>
>> hmm, so for descending, input - pts[i -1].x is negative and
>> we are adding that to pts[i-1].y, is that correct ?
>
> The formula used is to interpolate between two points using
> linear
>interpolation.
Right, agree. my question can be ignored.
[snip..]
>>> #define VADC_CHAN_TEMP(_dname, _pre)
>>> \
>>> - VADC_CHAN(_dname, IIO_TEMP, BIT(IIO_CHAN_INFO_PROCESSED), _pre) \
>>> + VADC_CHAN(_dname, IIO_TEMP, \
>>> + BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_PROCESSED), \
>>> + _pre) \
>>>
>>> #define VADC_CHAN_VOLT(_dname, _pre)
>>> \
>>> - VADC_CHAN(_dname, IIO_VOLTAGE, \
>>> - BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), \
>>> + VADC_CHAN(_dname, IIO_VOLTAGE, \
>>> + BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_PROCESSED),\
>>> _pre) \
>>>
>> For this and the below changes to VADC_CHAN_VOLT to TEMP, why is that done
>> ?
>> Now both macros are setting the same flags.
>
> For Voltage channels IIO_VOLTAGE is needed where as for Temperature
>channels IIO_TEMP is needed.
>
>>
>>> /*
>>> @@ -637,12 +811,11 @@ struct vadc_channels {
>>> VADC_CHAN_TEMP(DIE_TEMP, 0)
>>> VADC_CHAN_VOLT(REF_625MV, 0)
>>> VADC_CHAN_VOLT(REF_1250MV, 0)
>>> - VADC_CHAN_VOLT(CHG_TEMP, 0)
>>> + VADC_CHAN_TEMP(CHG_TEMP, 0)
>>> VADC_CHAN_VOLT(SPARE1, 0)
>>> VADC_CHAN_VOLT(SPARE2, 0)
>>> VADC_CHAN_VOLT(GND_REF, 0)
>>> VADC_CHAN_VOLT(VDD_VADC, 0)
>>> -
And also looks like the deletion of these and below
new lines are unnecessary ?
Regards,
Sricharan
