[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <20170309153748.tayxxf44cru7nlo6@ninjato>
Date: Thu, 9 Mar 2017 16:37:48 +0100
From: Wolfram Sang <wsa@...-dreams.de>
To: Javier Martinez Canillas <javier@....samsung.com>
Cc: linux-kernel@...r.kernel.org, Inki Dae <inki.dae@...sung.com>,
Andi Shyti <andi.shyti@...sung.com>,
Mauro Carvalho Chehab <mchehab@...pensource.com>,
Shuah Khan <shuahkh@....samsung.com>,
Kukjin Kim <kgene@...nel.org>,
linux-samsung-soc@...r.kernel.org,
Krzysztof Kozlowski <krzk@...nel.org>,
linux-i2c@...r.kernel.org, linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH] i2c: exynos5: Avoid transaction timeouts due
TRANSFER_DONE_AUTO not set
On Thu, Mar 09, 2017 at 11:05:33AM -0300, Javier Martinez Canillas wrote:
> After commit 7999eecb7e56 ("i2c: exynos5: fix arbitration lost handling"),
> some I2C transactions are failing because the TRANSFER_DONE_AUTO field is
> not set in the I2C_TRANS_STATUS register so the i2c->status value is left
> to -EINVAL causing the i2c->msg_complete completion to never be signaled.
>
> For example, when reading the time of an I2C rtc on an Exynos5800 machine:
>
> $ cat /sys/class/rtc/rtc0/time
> [ 25.924594] exynos5-hsi2c 12e10000.i2c: rx timeout
> [ 65.028365] max77686-rtc max77802-rtc: Fail to read time reg(-22)
> cat: /sys/class/rtc/rtc0/time: Invalid argument
>
> The Exynos5422 manual states clearly that most I2C_TRANS_STATUS reg bits
> (including TRANSFER_DONE_AUTO) are cleared after the register is read. So
> reading has side effects and should only be done if HSI2C_INT_I2C was set.
>
> Fixes: 7999eecb7e56 ("i2c: exynos5: fix arbitration lost handling")
> Signed-off-by: Javier Martinez Canillas <javier@....samsung.com>
> Reviewed-by: Andrzej Hajda <a.hajda@...sung.com>
>
Applied to for-current, thanks!
Download attachment "signature.asc" of type "application/pgp-signature" (834 bytes)
Powered by blists - more mailing lists