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

[Jonathan Cameron <jic23@kernel.org>]

On 12/01/16 15:27, Gabriele Mazzotta wrote:
> 2016-01-11 20:18 GMT+01:00 Jonathan Cameron <jic23@kernel.org>:
>> 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@gmail.com>
>>>>
>>>> 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.
> 
> I looked into this and Gnome uses iio-proxy-sensor to handle iio
> devices. As of now it, only looks for in_illuminance_input, so it
> currently doesn't work with acpi-als. I've also found a bug report [1]
> of an acpi-als user stating the same.
> 
> [1] https://github.com/hadess/iio-sensor-proxy/issues/46
Good fine. I'll apply this as a fix in that case and mark it for stable.

Jonathan
> 
>> 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?
>>
>> Jonathan
>>>
>>> Best regards,
>>> Marek Vasut
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-iio" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>
>>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-iio" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>