Message-ID: <aSR0tcV0ULNYvf7t@smile.fi.intel.com>
Date: Mon, 24 Nov 2025 17:07:33 +0200
From: Andy Shevchenko <andriy.shevchenko@...el.com>
To: Guenter Roeck <linux@...ck-us.net>
Cc: Romain Gantois <romain.gantois@...tlin.com>,
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Subject: Re: [PATCH v4 0/6] Add support for the LTM8054 voltage regulator

On Mon, Nov 24, 2025 at 06:57:41AM -0800, Guenter Roeck wrote:
> On 11/24/25 06:48, Romain Gantois wrote:
> > 
> > This is version four of my series which adds initial support of the Linear
> > Technology LTM8054 voltage regulator. The driver supports a fixed voltage
> > and a tunable output current limit using a DAC-controlled pin.
> > 
> > I'd say that the most unusual part of this series is the usage of the IIO
> > consumer API in a regulator driver. I think this makes sense here, since
> > the regulator driver has to access a DAC to read/set the output current
> > limit.
> 
> I don't think that is a valid reason. Literally every driver measuring voltages
> or current uses a DAC to do it. How else would one convert an analog value
> into a digital value ?

While I'm not objecting your vision on this, the ADC is also possible to use to
"measure" the analog signal. DAC approach IIRC considered cheaper solution, but
require an analogue comparator.

-- 
With Best Regards,
Andy Shevchenko

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