[PATCH] PM: Add resume event mapping for PMSG_POWEROFF

["Mario Limonciello (AMD)" <superm1@kernel.org>]

PM_EVENT_POWEROFF (0x0800) and PMSG_POWEROFF were already defined in
include/linux/pm.h. Add the resume_event() which is used when a shutdown
sequence needs to be aborted and the system should return to normal
operation.

This completes the PMSG_POWEROFF infrastructure needed to support
differentiating between hibernation and shutdown sequences when
re-using callbacks for common code.

Hibernation is started by writing a hibernation method (such as 'platform'
'shutdown', or 'reboot') to use into /sys/power/disk and writing 'disk' to
/sys/power/state.

Later shutdown will be initiated with the reboot() syscall with arguments
on whether to halt the system or power it off.

Tested-by: Eric Naim <dnaim@cachyos.org>
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
---
 drivers/base/power/main.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index e130da4281410..7265553ba24ca 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -1472,6 +1472,8 @@ static pm_message_t resume_event(pm_message_t sleep_state)
 		return PMSG_RECOVER;
 	case PM_EVENT_HIBERNATE:
 		return PMSG_RESTORE;
+	case PM_EVENT_POWEROFF:
+		return PMSG_ON;
 	}
 	return PMSG_ON;
 }
-- 
2.53.0