[PATCH 4.18 055/228] ACPI / button: increment wakeup count only when notified

[Greg Kroah-Hartman]

4.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Ravi Chandra Sadineni <ravisadineni@xxxxxxxxxxxx>

[ Upstream commit 7c058c7c74b3dbeb7d157c273959f87faf710350 ]

Because acpi_lid_initialize_state() is called on every system
resume and it triggers acpi_lid_notify_state() which invokes
acpi_pm_wakeup_event() for the lid device, the lid's wakeup count is
incremented even if the lid was not the source of the event that woke up
the system. That behavior confuses user space deamons using
wakeup_count to identify the potential system wakeup source. To avoid
the confusion, only trigger acpi_pm_wakeup_event() in the
acpi_button_notify() path and don't do that in the
acpi_lid_initialize_state() path.

Signed-off-by: Ravi Chandra Sadineni <ravisadineni@xxxxxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/acpi/button.c |   13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

--- a/drivers/acpi/button.c
+++ b/drivers/acpi/button.c
@@ -235,9 +235,6 @@ static int acpi_lid_notify_state(struct
 		button->last_time = ktime_get();
 	}
 
-	if (state)
-		acpi_pm_wakeup_event(&device->dev);
-
 	ret = blocking_notifier_call_chain(&acpi_lid_notifier, state, device);
 	if (ret == NOTIFY_DONE)
 		ret = blocking_notifier_call_chain(&acpi_lid_notifier, state,
@@ -366,7 +363,8 @@ int acpi_lid_open(void)
 }
 EXPORT_SYMBOL(acpi_lid_open);
 
-static int acpi_lid_update_state(struct acpi_device *device)
+static int acpi_lid_update_state(struct acpi_device *device,
+				 bool signal_wakeup)
 {
 	int state;
 
@@ -374,6 +372,9 @@ static int acpi_lid_update_state(struct
 	if (state < 0)
 		return state;
 
+	if (state && signal_wakeup)
+		acpi_pm_wakeup_event(&device->dev);
+
 	return acpi_lid_notify_state(device, state);
 }
 
@@ -384,7 +385,7 @@ static void acpi_lid_initialize_state(st
 		(void)acpi_lid_notify_state(device, 1);
 		break;
 	case ACPI_BUTTON_LID_INIT_METHOD:
-		(void)acpi_lid_update_state(device);
+		(void)acpi_lid_update_state(device, false);
 		break;
 	case ACPI_BUTTON_LID_INIT_IGNORE:
 	default:
@@ -409,7 +410,7 @@ static void acpi_button_notify(struct ac
 			users = button->input->users;
 			mutex_unlock(&button->input->mutex);
 			if (users)
-				acpi_lid_update_state(device);
+				acpi_lid_update_state(device, true);
 		} else {
 			int keycode;