Re: [PATCH 03/25] dt-bindings: iio: adc: exynos-adc: do not require syscon on S5Pv210

From: Krzysztof Kozlowski
Date: Tue Sep 08 2020 - 02:48:36 EST


On Mon, Sep 07, 2020 at 02:49:49PM -0700, Jonathan Bakker wrote:
> Looking at this again, it appears that there is actually control for
> it at offset 0x6818 of pmu_syscon (0xe0108000) [1]. However, it defaults to
> enabled so it's not required for proper use of the block. Whether it should
> be present in the schema/DTS is up to you.

Indeed the driver could turn off the ADC phy via syscon however bindings
(before YAML conversion) explicitly were saying that it is not needed. I
am not going to add it as I am not able to test the change and also
adding such requirement would be a break of ABI (described by first TXT
bindings).

Best regards,
Krzysztof


>
> Thanks,
> Jonathan
>
> [1] https://android.googlesource.com/kernel/samsung/+/refs/heads/android-samsung-3.0-jb-mr0/arch/arm/mach-s5pv210/include/mach/regs-clock.h#325
>
> On 2020-09-07 9:11 a.m., Krzysztof Kozlowski wrote:
> > The ADC in S5Pv210 does not have ADC phy registers in separate block for
> > which syscon would be needed. Remove this requirement to fix dtbs_check
> > warnings like:
> >
> > arch/arm/boot/dts/s5pv210-fascinate4g.dt.yaml: adc@e1700000: 'samsung,syscon-phandle' is a required property
> >
> > Signed-off-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
> > ---
> > .../devicetree/bindings/iio/adc/samsung,exynos-adc.yaml | 1 -
> > 1 file changed, 1 deletion(-)
> >
> > diff --git a/Documentation/devicetree/bindings/iio/adc/samsung,exynos-adc.yaml b/Documentation/devicetree/bindings/iio/adc/samsung,exynos-adc.yaml
> > index 89b4f9c252a6..75174af72288 100644
> > --- a/Documentation/devicetree/bindings/iio/adc/samsung,exynos-adc.yaml
> > +++ b/Documentation/devicetree/bindings/iio/adc/samsung,exynos-adc.yaml
> > @@ -81,7 +81,6 @@ allOf:
> > - samsung,exynos-adc-v2
> > - samsung,exynos3250-adc
> > - samsung,exynos4212-adc
> > - - samsung,s5pv210-adc
> > then:
> > required:
> > - samsung,syscon-phandle
> >