Taken from Linux kernel with minor modifications:
commit bf985969e27b507f734435a99df8bf745a3dbb2b
Author: Shawn Guo <shawn.guo@freescale.com>
Date: Mon Dec 20 22:57:43 2010 +0800
ARM: mxs: Add iomux support
Signed-off-by: Marek Vasut <marek.vasut@gmail.com>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Wolfgang Denk <wd@denx.de>
Cc: Detlev Zundel <dzu@denx.de>