RE: [PATCH] dt-bindings: iio: admv1014: make all regs required

[Miclaus, Antoniu]

> -----Original Message-----
> From: Jonathan Cameron <jic23@xxxxxxxxxx>
> Sent: Saturday, July 29, 2023 2:55 PM
> To: Miclaus, Antoniu <Antoniu.Miclaus@xxxxxxxxxx>
> Cc: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>;
> robh+dt@xxxxxxxxxx; krzysztof.kozlowski+dt@xxxxxxxxxx;
> conor+dt@xxxxxxxxxx; linux-iio@xxxxxxxxxxxxxxx;
> devicetree@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH] dt-bindings: iio: admv1014: make all regs required
> 
> [External]
> 
> On Thu, 27 Jul 2023 12:02:04 +0000
> "Miclaus, Antoniu" <Antoniu.Miclaus@xxxxxxxxxx> wrote:
> 
> > > -----Original Message-----
> > > From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
> > > Sent: Thursday, July 27, 2023 2:47 PM
> > > To: Miclaus, Antoniu <Antoniu.Miclaus@xxxxxxxxxx>; jic23@xxxxxxxxxx;
> > > robh+dt@xxxxxxxxxx; krzysztof.kozlowski+dt@xxxxxxxxxx;
> > > conor+dt@xxxxxxxxxx; linux-iio@xxxxxxxxxxxxxxx;
> > > devicetree@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> > > Subject: Re: [PATCH] dt-bindings: iio: admv1014: make all regs required
> > >
> > > [External]
> > >
> > > On 27/07/2023 13:31, Antoniu Miclaus wrote:
> > > > Since the regulators are required in the driver implementation, make
> > > > them required also in the bindings.
> 
> This bit is probably not strictly true.  Try no providing them and you will
> probably find stub regulators created on assumption they are fixed regs
> that we aren't interested in controlling.
> 
> > > >
> > >
> > > The true reason should be whether the hardware requires them.
> Because if
> > > hardware does not need some, the driver should be fixed.
> > The datasheet is not very explicit on this topic, but all the specifications of
> the
> > part are built around these pins being supplied.
> > Moreover, the evaluation board or the part comes with all VCC pins
> connected
> > to fixed supplies.
> 
> Agreed - these should be required in the binding.
> 
Hello Jonathan,

Not sure if I fully understand. Should I drop this patch? 
And also drop the "required" of the regulators in the admv1013 patch?
https://patchwork.kernel.org/project/linux-iio/patch/20230727110121.93546-1-antoniu.miclaus@xxxxxxxxxx/

Thanks,
> There was an old disagreement on this in which it they were not marked
> required in some bindings because the regulator subsystem would assume
> they
> were fixed supplies that were just missing in the DT and so provides stub
> regulators.
> My understanding at least has changed and now we mark the required even
> if
> the driver works fine on some boards without them being supplied.
> 
> Note though that this means the whole of trivial-devices.yaml is garbage
> as very few devices actually work without any power :)
> 
> Jonathan
> 
> 
> 
> > > Best regards,
> > > Krzysztof
> >