From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Osipenko Subject: Re: [PATCH v1] i2c: tegra: Make timeout error more informative Date: Tue, 10 Mar 2020 16:26:41 +0300 Message-ID: <017aad72-9872-a4aa-dc99-bd7d08c0db14@gmail.com> References: <20200302173512.2743-1-digetx@gmail.com> <20200310113706.GW1987@ninjato> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20200310113706.GW1987@ninjato> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Wolfram Sang Cc: Thierry Reding , Jonathan Hunter , Laxman Dewangan , linux-i2c@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-i2c@vger.kernel.org 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 :)