PM: Introduce PM_EVENT_HIBERNATE callback state

During the last step of hibernation in the "platform" mode (with the
help of ACPI) we use the suspend code, including the devices'
->suspend() methods, to prepare the system for entering the ACPI S4
system sleep state.

But at least for some devices the operations performed by the
->suspend() callback in that case must be different from its operations
during regular suspend.

For this reason, introduce the new PM event type PM_EVENT_HIBERNATE and
pass it to the device drivers' ->suspend() methods during the last phase
of hibernation, so that they can distinguish this case and handle it as
appropriate.  Modify the drivers that handle PM_EVENT_SUSPEND in a
special way and need to handle PM_EVENT_HIBERNATE in the same way.

These changes are necessary to fix a hibernation regression related
to the i915 driver (ref. http://lkml.org/lkml/2008/2/22/488).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Tested-by: Jeff Chua <jeff.chua.linux@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/scsi/aic7xxx/aic79xx_osm_pci.c b/drivers/scsi/aic7xxx/aic79xx_osm_pci.c
index 4150c8a..dfaaae5 100644
--- a/drivers/scsi/aic7xxx/aic79xx_osm_pci.c
+++ b/drivers/scsi/aic7xxx/aic79xx_osm_pci.c
@@ -89,7 +89,7 @@
 	pci_save_state(pdev);
 	pci_disable_device(pdev);
 
-	if (mesg.event == PM_EVENT_SUSPEND)
+	if (mesg.event & PM_EVENT_SLEEP)
 		pci_set_power_state(pdev, PCI_D3hot);
 
 	return rc;
diff --git a/drivers/scsi/aic7xxx/aic7xxx_osm_pci.c b/drivers/scsi/aic7xxx/aic7xxx_osm_pci.c
index dd6e21d..3d3eaef 100644
--- a/drivers/scsi/aic7xxx/aic7xxx_osm_pci.c
+++ b/drivers/scsi/aic7xxx/aic7xxx_osm_pci.c
@@ -134,7 +134,7 @@
 	pci_save_state(pdev);
 	pci_disable_device(pdev);
 
-	if (mesg.event == PM_EVENT_SUSPEND)
+	if (mesg.event & PM_EVENT_SLEEP)
 		pci_set_power_state(pdev, PCI_D3hot);
 
 	return rc;
diff --git a/drivers/scsi/mesh.c b/drivers/scsi/mesh.c
index 651d09b..fd63b06 100644
--- a/drivers/scsi/mesh.c
+++ b/drivers/scsi/mesh.c
@@ -1759,6 +1759,7 @@
 
 	switch (mesg.event) {
 	case PM_EVENT_SUSPEND:
+	case PM_EVENT_HIBERNATE:
 	case PM_EVENT_FREEZE:
 		break;
 	default:
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 37df8bb..7aee64d 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -1835,8 +1835,7 @@
 			goto done;
 	}
 
-	if (mesg.event == PM_EVENT_SUSPEND &&
-	    sdkp->device->manage_start_stop) {
+	if ((mesg.event & PM_EVENT_SLEEP) && sdkp->device->manage_start_stop) {
 		sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
 		ret = sd_start_stop_device(sdkp, 0);
 	}