Re: [PATCH 1/2] iio: light: ltr390: Add sysfs attribute to report data freshness

[Akshay Jindal]

On Thu, Jul 24, 2025 at 6:09 PM Jonathan Cameron <jic23@xxxxxxxxxx> wrote:
> Agreed.  Is the interrupt wired on this board?  If it is and you
> want to do filtering with the knowledge that the data is fresh then
> add a data ready trigger and buffered capture support.
> It's a much bigger job, but it is standard ABI and as such of more
> general use.
>
> Jonathan
>
Yes, the interrupt is wired in and enabled.

For LTR390, data_freshness is not the same as data-ready.
Here the sensor does not support a data-ready interrupt.
It only supports threshold violation interrupts where thresholds are
configurable.
LTR390 datasheet Pg 17:
https://optoelectronics.liteon.com/upload/download/DS86-2015-0004/LTR-390UV_Final_%20DS_V1%201.pdf

Correct me, if I am wrong, but as per my understanding, trigger based interrupts
are more appropriate where the application requires storing multiple samples
in a buffer at specific time intervals, provided the sensor supports
data-ready interrupts.


Thanks,
Akshay