Re: [PATCH] iio: light: acpi-als: Add a tuning parameter interface.

[Enric Balletbo Serra]

Hi Lars,

2016-09-06 12:31 GMT+02:00 Lars-Peter Clausen <lars@xxxxxxxxxx>:
> On 09/06/2016 12:25 PM, Enric Balletbo i Serra wrote:
>> From: Bryan Freed <bfreed@xxxxxxxxxxxx>
>>
>> Add IIO_CHAN_INFO_CALIBSCALE to the channel to scale up or down
>> the raw measurements through the IIO framework.
>>
>> Add IIO_CHAN_INFO_PROCESSED to provide the interface to read the
>> scaled measurements through the in_illuminance_input file.
>
> What is the use-case for this, how is this interface supposed to be used?

The idea behind this is be able to do a per-device calibration. The
use case we're thinking is:

 1. Read raw measurements from sensor in controlled environment (at
30, 500 and 1000 lux)
 2. do some math to calculate the calibration value.
 3. write the value to calibscale (in_illuminance_calibscale)
 4. read the calibrated measurement (in_illuminance_input)

Regards,
  Enric