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From:   Peter Korsgaard <peter@korsgaard.com>
To:     Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Cc:     Andrew Lunn <andrew@lunn.ch>,
        Federico Vaga <federico.vaga@cern.ch>,
        Wolfram Sang <wsa@kernel.org>, linux-i2c@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux@ew.tq-group.com,
        Gregor Herburger <gregor.herburger@tq-group.com>
Subject: Re: [PATCH v2] i2c: ocores: generate stop condition after timeout
 in polling mode
References: <20230413093737.15303-1-matthias.schiffer@ew.tq-group.com>
Date:   Thu, 13 Apr 2023 11:58:26 +0200
In-Reply-To: <20230413093737.15303-1-matthias.schiffer@ew.tq-group.com>
        (Matthias Schiffer's message of "Thu, 13 Apr 2023 11:37:37 +0200")
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>>>>> "Matthias" == Matthias Schiffer <matthias.schiffer@ew.tq-group.com> writes:

 > From: Gregor Herburger <gregor.herburger@tq-group.com>
 > In polling mode, no stop condition is generated after a timeout. This
 > causes SCL to remain low and thereby block the bus. If this happens
 > during a transfer it can cause slaves to misinterpret the subsequent
 > transfer and return wrong values.

 > To solve this, pass the ETIMEDOUT error up from ocores_process_polling()
 > instead of setting STATE_ERROR directly. The caller is adjusted to call
 > ocores_process_timeout() on error both in polling and in IRQ mode, which
 > will set STATE_ERROR and generate a stop condition.

 > Fixes: 69c8c0c0efa8 ("i2c: ocores: add polling interface")
 > Signed-off-by: Gregor Herburger <gregor.herburger@tq-group.com>
 > Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
 > ---

 > v2: style improvements based on feedback from Federico and Andrew. I went
 >     with a slightly different solution than Andrew suggested to avoid using
 >     the ret variable for two different kinds of returns.

Acked-by: Peter Korsgaard <peter@korsgaard.com>

-- 
Bye, Peter Korsgaard