PM: introduce set_target method in pm_ops
authorRafael J. Wysocki <rjw@sisk.pl>
Sun, 1 Jul 2007 19:07:33 +0000 (12:07 -0700)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Sun, 1 Jul 2007 19:29:44 +0000 (12:29 -0700)
commit2391dae3e36c19fe668c71eac2eb8344dbaaf46d
treeae8c1fa53fe67e3ccbb8c5097f6b5bda27b26959
parentcbcdd772ff43de58cc0d9de76ae9d05e2dd98bc0
PM: introduce set_target method in pm_ops

Commit 52ade9b3b97fd3bea42842a056fe0786c28d0555 changed the suspend code
ordering to execute pm_ops->prepare() after the device model per-device
.suspend() calls in order to fix some ACPI-related issues.  Unfortunately, it
broke the at91 platform which assumed that pm_ops->prepare() would be called
before suspending devices.

at91 used pm_ops->prepare() to get notified of the target system sleep state,
so that it could use this information while suspending devices.  However, with
the current suspend code ordering pm_ops->prepare() is called too late for
this purpose.  Thus, at91 needs an additional method in 'struct pm_ops' that
will be used for notifying the platform of the target system sleep state.
Moreover, in the future such a method will also be needed by ACPI.

This patch adds the .set_target() method to 'struct pm_ops' and makes the
suspend code call it, if implemented, before executing the device model
per-device .suspend() calls.  It also modifies the at91 code to use
pm_ops->set_target() instead of pm_ops->prepare().

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
arch/arm/mach-at91/pm.c
include/linux/pm.h
kernel/power/main.c