1 files changed, 24 insertions, 13 deletions

diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c
index d17fac453a30..764b8dfa04aa 100644
--- a/drivers/acpi/device_pm.c
+++ b/drivers/acpi/device_pm.c
@@ -966,6 +966,27 @@ int acpi_dev_suspend_late(struct device *dev)
 }
 EXPORT_SYMBOL_GPL(acpi_dev_suspend_late);
 
+static bool acpi_dev_needs_resume(struct device *dev, struct acpi_device *adev)
+{
+	u32 sys_target = acpi_target_system_state();
+	int ret, state;
+
+	if (device_may_wakeup(dev) != !!adev->wakeup.prepare_count)
+		return true;
+
+	if (sys_target == ACPI_STATE_S0)
+		return false;
+
+	if (adev->power.flags.dsw_present)
+		return true;
+
+	ret = acpi_dev_pm_get_state(dev, adev, sys_target, NULL, &state);
+	if (ret)
+		return true;
+
+	return state != adev->power.state;
+}
+
 /**
  * acpi_subsys_prepare - Prepare device for system transition to a sleep state.
  * @dev: Device to prepare.
@@ -973,26 +994,16 @@ EXPORT_SYMBOL_GPL(acpi_dev_suspend_late);
 int acpi_subsys_prepare(struct device *dev)
 {
 	struct acpi_device *adev = ACPI_COMPANION(dev);
-	u32 sys_target;
-	int ret, state;
+	int ret;
 
 	ret = pm_generic_prepare(dev);
 	if (ret < 0)
 		return ret;
 
-	if (!adev || !pm_runtime_suspended(dev)
-	    || device_may_wakeup(dev) != !!adev->wakeup.prepare_count)
-		return 0;
-
-	sys_target = acpi_target_system_state();
-	if (sys_target == ACPI_STATE_S0)
-		return 1;
-
-	if (adev->power.flags.dsw_present)
+	if (!adev || !pm_runtime_suspended(dev))
 		return 0;
 
-	ret = acpi_dev_pm_get_state(dev, adev, sys_target, NULL, &state);
-	return !ret && state == adev->power.state;
+	return !acpi_dev_needs_resume(dev, adev);
 }
 EXPORT_SYMBOL_GPL(acpi_subsys_prepare);