linux-kernel - Re: [PATCH 4/6] rtc: rv8803: Always apply the I²C workaround

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Message-ID: <20160721111008.GE4446@piout.net>
Date:	Thu, 21 Jul 2016 13:10:08 +0200
From:	Alexandre Belloni <alexandre.belloni@...e-electrons.com>
To:	Benoît Thébaudeau <benoit@...stem.com>
Cc:	rtc-linux@...glegroups.com, linux-kernel@...r.kernel.org,
	Alessandro Zummo <a.zummo@...ertech.it>
Subject: Re: [PATCH 4/6] rtc: rv8803: Always apply the I²C workaround

On 21/07/2016 at 12:41:30 +0200, Benoît Thébaudeau wrote :
> The I²C NACK issue of the RV-8803 may occur after any I²C START
> condition, depending on the timings. Consequently, the workaround must
> be applied for all the I²C transfers.
> 
> This commit abstracts the I²C transfer code into register access
> functions. This avoids duplicating the I²C workaround everywhere. This
> also avoids the duplication of the code handling the return value of
> i2c_smbus_read_i2c_block_data(). Error messages are issued in case of
> definitive register access failures (if the workaround fails). This
> change also makes the I²C transfer return value checks consistent.
> 

Well, my initial idea was that the workaround is actually needed only
for operations that are not restartable from userspace.

Did you it that bug? On which RTC?

-- 
Alexandre Belloni, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com