A pointer to wm8400_regulator_probe is passed to the core via
platform_driver_register and so the function must not disappear when the
.init sections are discarded.  Otherwise (if also having HOTPLUG=y)
unbinding and binding a device to the driver via sysfs will result in an
oops as does a device being registered late.

An alternative to this patch is using platform_driver_probe instead of
platform_driver_register plus removing the pointer to the probe function
from the struct platform_driver.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NLiam Girdwood <lrg@slimlogic.co.uk>

The WM8400 provides two programmable DCDC step-down (buck) convertors
and four low-dropout (LDO) regulators. This driver provides support for
runtime managment of these in the standard regulator API.

Support for configuration of the suspend and hibernate mode behaviour
of the regulators is not yet included.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: NLiam Girdwood <lrg@slimlogic.co.uk>