Re: [PATCH] iio: adc: ad7192: Change "shorted" channels to differential

Nuno Sá
2023-03-31T06:26:34Z

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 = 2 and .extended_name
> set
> to "shorted".
>
> The problem with this approach, is that the driver provided two IIO
> channels with the identifier .channel = 2; one "shorted" and the
> other
> not. This goes against the IIO ABI, as a channel identifier should be
> unique.
>
> Address this issue by changing "shorted" channels to being
> differential
> instead, with channel 2 vs. itself, as we're actually measuring AIN2
> vs.
> itself.
>
> 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.
>
> 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>