From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wolfram Sang <wsa@the-dreams.de>
Subject: Re: [PATCH v4 1/3] i2c: imx: Fix race condition in dma read
Date: Mon, 20 Aug 2018 11:13:38 +0200
Message-ID: <20180820091338.x2nofnytf7z27omk@ninjato>
References: <20180816084315.7857-1-esben.haabendal@gmail.com>
 <20180816084315.7857-2-esben.haabendal@gmail.com>
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To: Esben Haabendal <esben.haabendal@gmail.com>
Cc: linux-i2c@vger.kernel.org, Esben Haabendal <eha@deif.com>, Wolfram Sang <wsa+renesas@sang-engineering.com>, Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= <u.kleine-koenig@pengutronix.de>, Lucas Stach <l.stach@pengutronix.de>, Phil Reid <preid@electromag.com.au>, Fabio Estevam <fabio.estevam@nxp.com>, Peter Rosin <peda@axentia.se>, linux-kernel@vger.kernel.org
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On Thu, Aug 16, 2018 at 10:43:12AM +0200, Esben Haabendal wrote:
> From: Esben Haabendal <eha@deif.com>
>=20
> This fixes a race condition, where the DMAEN bit ends up being set after
> I2C slave has transmitted a byte following the dummy read.  When that
> happens, an interrupt is generated instead, and no DMA request is generat=
ed
> to kickstart the DMA read, and a timeout happens after DMA_TIMEOUT (1 sec=
).
>=20
> Fixed by setting the DMAEN bit before the dummy read.
>=20
> Signed-off-by: Esben Haabendal <eha@deif.com>
> Acked-by: Uwe Kleine-K=C3=B6nig <u.kleine-koenig@pengutronix.de>

Applied to for-next and added stable, thanks!


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