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

[Marek Vasut]

On Monday, January 11, 2016 at 08:18:27 PM, Jonathan Cameron wrote:
> On 09/01/16 17:27, Marek Vasut wrote:
> > 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 ?
> 
> It's more than likely as Gnome at least supports using them to control
> screen brightness.  Hopefully that code is able to cope with the correct
> ABI though as well as the old one.  Anyhow, we seem to have a reasonable
> consensus. Gabriele, are you happy to do a version of the patch with the
> _RAW version left along side your _PROCESSED version and a comment saying
> that it is for compatibility only?

This makes sense in my mind, thanks :)

Best regards,
Marek Vasut