Re: [PATCH] iio: light: acpi-als: Report data as processed rather than raw

From: Marek Vasut
Date: Sat Jan 09 2016 - 12:28:07 EST


On Saturday, January 09, 2016 at 05:31:24 PM, Jonathan Cameron wrote:
> On 07/01/16 15:21, Gabriele Mazzotta wrote:
> > As per the ACPI specification (Revision 5.0) [1], the data coming
> > from the sensor represent the ambient light illuminance reading
> > expressed in lux. Use IIO_CHAN_INFO_PROCESSED instead of
> > IIO_CHAN_INFO_RAW to signify that the data are pre-processed.
> >
> > [1] http://www.acpi.info/DOWNLOADS/ACPIspec50.pdf
> >
> > Signed-off-by: Gabriele Mazzotta <gabriele.mzt@xxxxxxxxx>
>
> Hm. Whilst it's a fix in a sense, the original didn't really 'break'
> the ABI so I worry a little that this change may break others.
> Irritating as it is, perhaps we should keep the _RAW and add _PROCESSED
> (which will then be exactly the same value).
> We'll also then need a comment in the code, that leaving the _RAW
> elements was for ABI compatibility.
>
> What do others think?

I'm not an IIO guru, but this does sound sensible. Do you know if any userland
code which actually uses the ACPI ALS already ?

Best regards,
Marek Vasut