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>
diff --git a/include/linux/suspend.h b/include/linux/suspend.h
index a697742..e8e6915 100644
--- a/include/linux/suspend.h
+++ b/include/linux/suspend.h
@@ -86,6 +86,11 @@
* that implement @begin(), but platforms implementing @begin() should
* also provide a @end() which cleans up transitions aborted before
* @enter().
+ *
+ * @recover: Recover the platform from a suspend failure.
+ * Called by the PM core if the suspending of devices fails.
+ * This callback is optional and should only be implemented by platforms
+ * which require special recovery actions in that situation.
*/
struct platform_suspend_ops {
int (*valid)(suspend_state_t state);
@@ -94,6 +99,7 @@
int (*enter)(suspend_state_t state);
void (*finish)(void);
void (*end)(void);
+ void (*recover)(void);
};
#ifdef CONFIG_SUSPEND
@@ -149,7 +155,7 @@
* The methods in this structure allow a platform to carry out special
* operations required by it during a hibernation transition.
*
- * All the methods below must be implemented.
+ * All the methods below, except for @recover(), must be implemented.
*
* @begin: Tell the platform driver that we're starting hibernation.
* Called right after shrinking memory and before freezing devices.
@@ -189,6 +195,11 @@
* @restore_cleanup: Clean up after a failing image restoration.
* Called right after the nonboot CPUs have been enabled and before
* thawing devices (runs with IRQs on).
+ *
+ * @recover: Recover the platform from a failure to suspend devices.
+ * Called by the PM core if the suspending of devices during hibernation
+ * fails. This callback is optional and should only be implemented by
+ * platforms which require special recovery actions in that situation.
*/
struct platform_hibernation_ops {
int (*begin)(void);
@@ -200,6 +211,7 @@
void (*leave)(void);
int (*pre_restore)(void);
void (*restore_cleanup)(void);
+ void (*recover)(void);
};
#ifdef CONFIG_HIBERNATION