Suspend-related patches for 2.6.27

ACPI PM: Add possibility to change suspend sequence

There are some systems out there that don't work correctly with
our current suspend/hibernation code ordering.  Provide a workaround
for these systems allowing them to pass 'acpi_sleep=old_ordering' in
the kernel command line so that it will use the pre-ACPI 2.0 ("old")
suspend code ordering.

Unfortunately, this requires us to add a platform hook to the
resuming of devices for recovering the platform in case one of the
device drivers' .suspend() routines returns error code.  Namely,
ACPI 1.0 specifies that _PTS should be called before suspending
devices, but _WAK still should be called before resuming them in
order to undo the changes made by _PTS.  However, if there is an
error during suspending devices, they are automatically resumed
without returning control to the PM core, so the _WAK has to be
called from within device_resume() in that cases.

The patch also reorders and refactors the ACPI suspend/hibernation
code to avoid duplication as far as reasonably possible.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 7 insertions, 3 deletions

diff --git a/kernel/power/main.c b/kernel/power/main.c
index d023b6b584e5..3398f4651aa1 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -269,11 +269,11 @@ int suspend_devices_and_enter(suspend_state_t state)
         error = device_suspend(PMSG_SUSPEND);
         if (error) {
                 printk(KERN_ERR "PM: Some devices failed to suspend\n");
-                goto Resume_console;
+                goto Recover_platform;
         }
 
         if (suspend_test(TEST_DEVICES))
-                goto Resume_devices;
+                goto Recover_platform;
 
         if (suspend_ops->prepare) {
                 error = suspend_ops->prepare();
@@ -294,12 +294,16 @@ int suspend_devices_and_enter(suspend_state_t state)
                 suspend_ops->finish();
  Resume_devices:
         device_resume(PMSG_RESUME);
- Resume_console:
         resume_console();
  Close:
         if (suspend_ops->end)
                 suspend_ops->end();
         return error;
+
+ Recover_platform:
+        if (suspend_ops->recover)
+                suspend_ops->recover();
+        goto Resume_devices;
 }
 
 /**