Factor out some boilerplate code.
Signed-off-by: NAxel Lin <axel.lin@gmail.com>
Acked-by: NMarek Vasut <marek.vasut@gmail.com>
Acked-by: NRobert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>