Re: [PATCH v2] I2C: mpc: insert DR read in i2c_fixup()

[Wolfram Sang <wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org>]

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On Tue, Jun 03, 2014 at 11:00:32AM +0200, Valentin Longchamp wrote:
> The mpc_i2c_fixup function is called when the bus is not released by a
> slave. The function generates 9 pulses that should lead the slave
> to release the bus.
> 
> The sequence that generates the pulses disables/enables the I2C module
> that controls the blocked bus. We have found out on the P2041 SoC that
> this could cause the CPU to hang (for a short delay).
> 
> To avoid this, this patch introduces a read to the I2CDR register
> between the re-enablement of the I2C module in master mode and its
> returning to the slave mode instead of the delay (the final delay,
> between the pulses is kept), as proposed in procedure from the P2041
> reference manual (16.6.2.3), and the other manuals from the mpc83xx and
> mpc85xx families.
> 
> Signed-off-by: Rainer Boschung <rainer.boschung-SkAbAL50j+5BDgjK7y7TUQ@public.gmane.org>
> Signed-off-by: Valentin Longchamp <valentin.longchamp-SkAbAL50j+5BDgjK7y7TUQ@public.gmane.org>
> 

Applied to for-next, thanks!


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