From: Marek Vasut <marex@denx.de>
To: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Subject: Re: [PATCH] iio: acpi: Add ACPI0008 Ambient Light Sensor
Date: Wed, 29 Apr 2015 16:33:18 +0200
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On Wednesday, April 29, 2015 at 01:51:21 PM, Gabriele Mazzotta wrote:
> On Wednesday 29 April 2015 13:27:25 Gabriele Mazzotta wrote:
> > Add basic implementation of the ACPI0008 Ambient Light Sensor driver.
> > This driver currently supports only the ALI property, yet is ready to
> > be easily extended to handle ALC, ALT, ALP ones as well.
> > 
> > Signed-off-by: Martin Liska <marxin.liska@gmail.com>
> > Signed-off-by: Marek Vasut <marex@denx.de>
> > Signed-off-by: Gabriele Mazzotta <gabriele.mzt@gmail.com>
> > Cc: Zhang Rui <rui.zhang@intel.com>
> > ---
> > This continues http://marc.info/?t=140163463200002
> > 
> > I've made few adjustments over the original patch:
> >  - Code aligned with 4.1-rc1 and cleaned up
> >  - Use signed integers to store values: sensors report 32bit signed
> >  
> >    values. In particular, -1 is reported when the current reading
> >    is above the supported range of sensitivity.
> > 
> > Most of the changes are just a consequence of the changes in the
> > iio subsystem.
> > 
> > Gabriele
> 
> I'm sorry, I've just noticed that I haven't changed the value of
> realbits in acpi_als_channels. This makes me wonder what would be the
> proper value, given that this is a generic driver and all the
> information I have are those in the ACPI specification (which states
> what I reported here above).
> 
> Should I just set realbits to 32?

I believe the ALS reports only 16bit signel value, no ?
My observation with a strong coherent light source is that
the saturated sensor reported 0xffff .

Best regards,
Marek Vasut
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