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Date:   Fri, 8 Dec 2023 10:50:15 -0300
From:   Marcelo Schmitt <marcelo.schmitt1@gmail.com>
To:     David Lechner <dlechner@baylibre.com>
Cc:     Marcelo Schmitt <marcelo.schmitt@analog.com>, apw@canonical.com,
        joe@perches.com, dwaipayanray1@gmail.com, lukas.bulwahn@gmail.com,
        paul.cercueil@analog.com, Michael.Hennerich@analog.com,
        lars@metafoo.de, jic23@kernel.org, robh+dt@kernel.org,
        krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org,
        dan.carpenter@linaro.org, linux-iio@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3 00/13] Add support for AD7091R-2/-4/-8
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References: <cover.1701971344.git.marcelo.schmitt1@gmail.com>
 <CAMknhBFPbAqp4-AQdmbp+VRW-Ksk1PxaLCG+3n=Zk4gyStqhgw@mail.gmail.com>
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On 12/07, David Lechner wrote:
> On Thu, Dec 7, 2023 at 12:36 PM Marcelo Schmitt
> <marcelo.schmitt@analog.com> wrote:
> >
> > From: Marcelo Schmitt <marcelo.schmitt1@gmail.com>
> >
[...]
> >
> > I see regmap's interface for reading device registers under /sys/kernel/debug/regmap/.
> > I can read all registers but can't write to any of them unless I force define
> > REGMAP_ALLOW_WRITE_DEBUGFS.
> >
> > When testing events for this driver I often write to device registers
> > to set different rising/falling thresholds. I do something like this:
> > # echo 0x17 0x100 > /sys/kernel/debug/iio/iio:device0/direct_reg_access
> >
> > I tried read/writing to files under iio:device events directory but always
> > get segmentation fault. I must be forgetting to implement something.
> > What am I missing?
> >
> 
> It looks like event callbacks (.read_event_value and friends) are
> missing from `static const struct iio_info ad7091r_info = { ... }`.
> These callbacks aren't checked for NULL, e.g. in iio_ev_value_show(),
> so that is likely where the segfault is happening.

Hi David, thank you for pointing that out.
Will implement those calls in v4.