Re: [PATCH] iio: adc: Add scaling support to exynos adc driver

[Jonathan Cameron]

On Mon, 11 May 2020 09:42:32 +0200
Krzysztof Kozlowski <krzk@xxxxxxxxxx> wrote:

> On Sun, May 10, 2020 at 11:24:17AM +0100, Jonathan Cameron wrote:
> > On Fri,  8 May 2020 14:14:00 -0700
> > Jonathan Bakker <xc-racer2@xxxxxxx> wrote:
> >   
> > > Currently the driver only exposes the raw counts.  As we
> > > have the regulator voltage and the maximum value (stored in
> > > the data mask), we can trivially produce a scaling fraction
> > > of voltage / max value.
> > > 
> > > This assumes that the regulator voltage is in fact the max
> > > voltage, which appears to be the case for all mainline dts
> > > and cross referenced with the public Exynos4412 and S5PV210
> > > datasheets.
> > > 
> > > Signed-off-by: Jonathan Bakker <xc-racer2@xxxxxxx>  
> > 
> > Seems reasonable to me. I'd like an exynos Ack though before applying.  
> 
> 
> It's correct, at least with ARMv7 Exynos datasheets
> 
> The few ARMv8 Exynos chips are silent about the voltage levels. The
> Exynos 7 DTS board in mainline kernel does not have regulator but it
> looks clearly like mistake.
> 
> I think they behave the same, so for Exynos:
> Reviewed-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
Applied to the togreg branch of iio.git and pushed out as testing
for the autobuilders to poke at it.

Thanks,

Jonathan

> 
> Best regards,
> Krzysztof
> 
> > thanks,
> > 
> > Jonathan
> > 
> >