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Message-ID: <cf20f272465717da960ae3a3c04eb6c1ebfaf3d3.camel@gmail.com>
Subject: Re: [PATCH] iio: adc: ad7192: Change "shorted" channels to
 differential
From:   Nuno =?ISO-8859-1?Q?S=E1?= <noname.nuno@gmail.com>
To:     Paul Cercueil <paul@crapouillou.net>,
        Jonathan Cameron <jic23@kernel.org>,
        Lars-Peter Clausen <lars@metafoo.de>,
        Michael Hennerich <Michael.Hennerich@analog.com>
Cc:     linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org,
        Alisa Roman <alisa.roman@analog.com>
Date:   Fri, 31 Mar 2023 08:26:12 +0200
In-Reply-To: <20230330102100.17590-1-paul@crapouillou.net>
References: <20230330102100.17590-1-paul@crapouillou.net>
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On Thu, 2023-03-30 at 12:21 +0200, Paul Cercueil wrote:
> The AD7192 provides a specific channel configuration where both
> negative
> and positive inputs are connected to AIN2. This was represented in
> the
> ad7192 driver as a IIO channel with .channel =3D 2 and .extended_name
> set
> to "shorted".
>=20
> The problem with this approach, is that the driver provided two IIO
> channels with the identifier .channel =3D 2; one "shorted" and the
> other
> not. This goes against the IIO ABI, as a channel identifier should be
> unique.
>=20
> Address this issue by changing "shorted" channels to being
> differential
> instead, with channel 2 vs. itself, as we're actually measuring AIN2
> vs.
> itself.
>=20
> Note that the fix tag is for the commit that moved the driver out of
> staging. The bug existed before that, but backporting would become
> very
> complex further down and unlikely to happen.
>=20
> Fixes: b581f748cce0 ("staging: iio: adc: ad7192: move out of
> staging")
> Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> Co-developed-by: Alisa Roman <alisa.roman@analog.com>
> Signed-off-by: Alisa Roman <alisa.roman@analog.com>
> ---

Reviewed-by: Nuno Sa <nuno.sa@analog.com>