Re: [PATCH v4 2/4] dt-bindings: regulator: add bindings for output-supply

From: Zev Weiss <zev@bewilderbeest.net>
To: Rob Herring <robh@kernel.org>
Cc: Mark Brown <broonie@kernel.org>,
	Naresh Solanki <naresh.solanki@9elements.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Liam Girdwood <lgirdwood@gmail.com>,
	Patrick Rudolph <patrick.rudolph@9elements.com>
Subject: Re: [PATCH v4 2/4] dt-bindings: regulator: add bindings for output-supply
Date: Thu, 21 Jul 2022 01:33:20 -0700	[thread overview]
Message-ID: <YtkPUOh5XiQyGLxw@hatter.bewilderbeest.net> (raw)
In-Reply-To: <CAL_JsqKCByvNASAxRWV3bcjFSBjXZUQf0Xvv_dCZ0z1CRCcOKA@mail.gmail.com>

On Thu, Jul 14, 2022 at 09:59:48AM PDT, Rob Herring wrote:
>+Zev
>
>On Thu, Jul 14, 2022 at 9:54 AM Mark Brown <broonie@kernel.org> wrote:
>>
>> On Thu, Jul 14, 2022 at 09:07:49AM -0600, Rob Herring wrote:
>> > On Thu, Jul 14, 2022 at 8:43 AM Mark Brown <broonie@kernel.org> wrote:
>>
>> > > Consider for example a BMC (IIRC that's what their specific product is),
>> > > a bench supply or some automated test equipment.  Part of the function
>> > > for these systems is to provide power to other systems which would be
>> > > represented as a root or wall supply in the description of the system
>> > > that actually uses the supply if it were described using DT.
>>
>> > Didn't someone else have a similar use recently? Controlling some
>> > supply external to the system. I can't seem to find it now.
>>
>> IIRC that was an earlier iteration of the same thing - it's been round
>> the houses a bit.  extcon seemed like it might be a home since these are
>> external connections from the system but in the end people didn't think
>> it looked like a good fit.
>
>Found it:
>
>v1: https://lore.kernel.org/all/20220504065252.6955-2-zev@bewilderbeest.net/
>v2: https://lore.kernel.org/all/20220505232557.10936-1-zev@bewilderbeest.net/
>
>v2 was the using extcon version. v1 looks pretty similar to this one
>though anything that's just a compatible plus supplies would.
>
>But AFAICT these 2 submissions are completely independent.
>

Thanks for looping me in here Rob, I hadn't been aware of this series.

Naresh, I'd appreciate it if you could CC me on any subsequent 
iterations; as linked above I've made some sporadic attempts at getting 
support for this functionality merged, and am certainly interested in 
any other efforts on that front.

A question for Mark though -- in one of my earliest stabs at this I 
floated the idea of using reg-userspace-consumer for it, but was told in 
no uncertain terms that that driver was for testing only and should 
under no circumstances ever be instantiated in a production system.  Has 
the thinking on its usage changed in the last year or so such that this 
approach was deemed okay?

Thanks,
Zev