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Subject: Re: [PATCH v1] i2c: tegra: Make timeout error more informative
To:     Wolfram Sang <wsa@the-dreams.de>
Cc:     Thierry Reding <thierry.reding@gmail.com>,
        Jonathan Hunter <jonathanh@nvidia.com>,
        Laxman Dewangan <ldewangan@nvidia.com>,
        linux-i2c@vger.kernel.org, linux-tegra@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20200302173512.2743-1-digetx@gmail.com>
 <20200310113706.GW1987@ninjato>
From:   Dmitry Osipenko <digetx@gmail.com>
Message-ID: <017aad72-9872-a4aa-dc99-bd7d08c0db14@gmail.com>
Date:   Tue, 10 Mar 2020 16:26:41 +0300
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10.03.2020 14:37, Wolfram Sang пишет:
> On Mon, Mar 02, 2020 at 08:35:12PM +0300, Dmitry Osipenko wrote:
>> The I2C timeout error message doesn't tell us what exactly failed and some
>> I2C client drivers do not clarify the error either. Adding WARN_ON_ONCE()
>> results in a stacktrace being dumped into KMSG, which is very useful for
>> debugging purposes.
> 
> This is good for debugging, in deed, yet not good in the generic case.
> Timeouts are not an exception on the I2C bus (think of an EEPROM which
> is busy during an erase cycle), so it shouldn't be printed at all.
> 
> This prinout should rather be dropped or at least be dev_dbg.

Oh, well. I'll keep this debugging applied locally then, it's quite
unfortunate when something fails silently :)