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Date:   Wed, 24 May 2023 10:34:31 +0100
From:   Andre Przywara <andre.przywara@arm.com>
To:     Maxim Kiselev <bigunclemax@gmail.com>
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Subject: Re: [RFC PATCH v1 0/4] Add support for Allwinner GPADC on
 D1/T113s/R329 SoCs
Message-ID: <20230524103431.50c6a2fd@donnerap.cambridge.arm.com>
In-Reply-To: <20230524082744.3215427-1-bigunclemax@gmail.com>
References: <20230524082744.3215427-1-bigunclemax@gmail.com>
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On Wed, 24 May 2023 11:27:29 +0300
Maxim Kiselev <bigunclemax@gmail.com> wrote:

Hi Maxim,

many thanks for your work on this and for posting it!

> This series adds support for general purpose ADC (GPADC) on new
> Allwinner's SoCs, such as D1, T113s and R329. The implemented driver
> provides basic functionality for getting ADC channels data.
> 
> All of the listed SoCs have the same IP. The only difference is the number
> of available channels:
>      T113 - 1 channel
>      D1   - 2 channels
>      R329 - 4 channels

This may sound kind of obvious, but wouldn't it be easier to model this
with one compatible string, and have the number of channels as a DT
property?
Or, alternatively, using iio/multiplexer/io-channel-mux.yaml, since it's
only one ADC anyway?

And btw: it seems that the T507 (the H616 die with a different pinout) has
the same IP, with four channels:
http://dl.linux-sunxi.org/T507/

Cheers,
Andre

> This series is just an RFC and I would be glad to see any comments
> about it.
> 
> 
> Maxim Kiselev (4):
>   iio: adc: Add Allwinner D1/T113s/R329 SoCs GPADC
>   dt-bindings: iio: adc: Add Allwinner D1/T113s/R329 SoCs GPADC
>   ARM: dts: sun8i: t113s: Add GPADC node
>   riscv: dts: allwinner: d1: Add GPADC node
> 
>  .../iio/adc/allwinner,sun20i-d1-gpadc.yaml    |  52 ++++
>  arch/arm/boot/dts/sun8i-t113s.dtsi            |  12 +
>  arch/riscv/boot/dts/allwinner/sun20i-d1.dtsi  |  10 +
>  drivers/iio/adc/Kconfig                       |  10 +
>  drivers/iio/adc/Makefile                      |   1 +
>  drivers/iio/adc/sun20i-gpadc-iio.c            | 275 ++++++++++++++++++
>  6 files changed, 360 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/iio/adc/allwinner,sun20i-d1-gpadc.yaml
>  create mode 100644 drivers/iio/adc/sun20i-gpadc-iio.c
>