i2c-core: Fix for lockdep validator
authorJean Delvare <khali@linux-fr.org>
Mon, 10 Sep 2012 08:14:02 +0000 (10:14 +0200)
committerJean Delvare <khali@endymion.delvare>
Mon, 10 Sep 2012 08:14:02 +0000 (10:14 +0200)
commit390946b17260797635cd9e65496b5a17b2db0a5d
tree42c4f0a172149d7e6752ddf55284cb1fcb386eec
parente68bb91baa0bb9817567bd45d560919e8e26373b
i2c-core: Fix for lockdep validator

If kernel is compiled with CONFIG_PROVE_LOCKING the
validator raises an error when a multiplexer is removed
via sysfs and sub-clients are connected to it. This is a
false positive.
Documentation/lockdep-design.txt recommends to handle this
via calls to mutex_lock_nested().

Based on an earlier fix from Michael Lawnick.

Note that the extra code resolves to nothing unless
CONFIG_DEBUG_LOCK_ALLOC=y.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Michael Lawnick <ml.lawnick@gmx.de>
drivers/i2c/i2c-core.c