Eric Miao writes:
 > On Wed, Sep 23, 2009 at 9:50 AM, Kevin Hilman
 > [off-list ref] wrote:
 > > On ARM platforms, power management can be very platform specific.
 > > This patch allows ARM subarches to extend the platform_device
 > > pdev_archdata for each subarch by creating a new struct pdev_machdata
 > > and allowing each subarch to customize it as needed.
 > >
 > > As a starting point, each subarch's <mach/device.h> creates an empty
 > > struct pdev_machdata.
 > >
 > 
 > Shouldn't that pdev_archdata and pdev_machdata be pointer or something
 > so that multiple platform_device can share something in common?

Forcing it to be a pointer has allocation and lifetime implications.
Making it a struct allows the subarch to duplicate or share
(via a private pointer) data as it sees fit.