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Subject: Re: [PATCH 0/2] iio: adc: Add a current from voltage driver
To:     Lars-Peter Clausen <lars@metafoo.de>, jic23@kernel.org,
        knaack.h@gmx.de, pmeerw@pmeerw.net, robh+dt@kernel.org,
        linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org,
        devicetree@vger.kernel.org
Cc:     linus.walleij@linaro.org
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 <d5f785bf-15f5-9ca5-f7f8-863c74447010@metafoo.de>
From:   Jonathan Bakker <xc-racer2@live.ca>
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Date:   Sat, 16 May 2020 08:01:12 -0700
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Oops, sorry about that, you're absolutely right.  The current-sense-shunt part
of iio-rescale is exactly what I was looking for.

Thanks,
Jonathan

On 2020-05-15 11:28 p.m., Lars-Peter Clausen wrote:
> 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
> 
>