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Subject: Re: [PATCH 0/2] iio: adc: Add a current from voltage driver
To:     Jonathan Bakker <xc-racer2@live.ca>, jic23@kernel.org,
        knaack.h@gmx.de, pmeerw@pmeerw.net, robh+dt@kernel.org,
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        devicetree@vger.kernel.org
Cc:     linus.walleij@linaro.org
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From:   Lars-Peter Clausen <lars@metafoo.de>
Message-ID: <d5f785bf-15f5-9ca5-f7f8-863c74447010@metafoo.de>
Date:   Sat, 16 May 2020 08:28:35 +0200
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On 5/16/20 4:26 AM, Jonathan Bakker wrote:
> In the discussion around adding the GP2A002 light driver, there came
> up the question of what to do when a system emulates a current ADC
> by using a voltage ADC and a resistor.  Rather than adding it on
> a per-driver basis, it was suggested(1) to add a minimal IIO driver
> to support this situation.
>
> The new driver is fairly simple - it simply takes a voltage ADC and
> a resistor value in ohms exposed as the scale and outputs a current.
>
> It has been tested on a first-gen Galaxy S device which has the above
> mentioned GP2A002 chip connected to the voltage ADC resistor complex.
>
> 1) https://lore.kernel.org/linux-iio/20200202150843.762c6897@archlinux/

Hi,

There is afe/iio-rescale.c, which I think already implements this 
functionality.

- Lars