Provide basic support for MFDs having multiple cells of a given
type with different IDs by adding an id to the mfd_cell structure
and then adding that to the id passed in to mfd_add_devices().

As it stands this approach requires that MFDs using this feature
deal with ensuring that there aren't any ID collisions resulting
from multiple MFDs of the same type being instantiated. This needs
to happen with the existing code too, but with this approach there
is a knock on effect on the IDs for non-duplicated devices.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@openedhand.com>

Adding platform_data to mfd_cell allows passing of platform data directly
to the platform_device created for each cell and thus reuse of existing
drivers.
On the other side it can be used as a hook to mfd_cell itself
removing the need in mfd_get_cell method.

Signed-off-by: Mike Rapoport <mike@compulab.co.il>
Acked-by: Dmitry Baryshkov <dbaryshkov@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@openedhand.com>

Fix some coding style fixes in the mfd core driver.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Samuel Ortiz <sameo@openedhand.com>

This patch provides a common subdevice registration system for MFD type
chips, using platfrom device.

Signed-off-by: Ian Molton <spyro@f2s.com>
Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>