v4.19.13 snapshot.
diff --git a/drivers/acpi/wakeup.c b/drivers/acpi/wakeup.c
new file mode 100644
index 0000000..9614126
--- /dev/null
+++ b/drivers/acpi/wakeup.c
@@ -0,0 +1,98 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * wakeup.c - support wakeup devices
+ * Copyright (C) 2004 Li Shaohua <shaohua.li@intel.com>
+ */
+
+#include <linux/init.h>
+#include <linux/acpi.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+
+#include "internal.h"
+#include "sleep.h"
+
+/*
+ * We didn't lock acpi_device_lock in the file, because it invokes oops in
+ * suspend/resume and isn't really required as this is called in S-state. At
+ * that time, there is no device hotplug
+ **/
+#define _COMPONENT		ACPI_SYSTEM_COMPONENT
+ACPI_MODULE_NAME("wakeup_devices")
+
+/**
+ * acpi_enable_wakeup_devices - Enable wake-up device GPEs.
+ * @sleep_state: ACPI system sleep state.
+ *
+ * Enable wakeup device power of devices with the state.enable flag set and set
+ * the wakeup enable mask bits in the GPE registers that correspond to wakeup
+ * devices.
+ */
+void acpi_enable_wakeup_devices(u8 sleep_state)
+{
+	struct list_head *node, *next;
+
+	list_for_each_safe(node, next, &acpi_wakeup_device_list) {
+		struct acpi_device *dev =
+			container_of(node, struct acpi_device, wakeup_list);
+
+		if (!dev->wakeup.flags.valid
+		    || sleep_state > (u32) dev->wakeup.sleep_state
+		    || !(device_may_wakeup(&dev->dev)
+		        || dev->wakeup.prepare_count))
+			continue;
+
+		if (device_may_wakeup(&dev->dev))
+			acpi_enable_wakeup_device_power(dev, sleep_state);
+
+		/* The wake-up power should have been enabled already. */
+		acpi_set_gpe_wake_mask(dev->wakeup.gpe_device, dev->wakeup.gpe_number,
+				ACPI_GPE_ENABLE);
+	}
+}
+
+/**
+ * acpi_disable_wakeup_devices - Disable devices' wakeup capability.
+ * @sleep_state: ACPI system sleep state.
+ */
+void acpi_disable_wakeup_devices(u8 sleep_state)
+{
+	struct list_head *node, *next;
+
+	list_for_each_safe(node, next, &acpi_wakeup_device_list) {
+		struct acpi_device *dev =
+			container_of(node, struct acpi_device, wakeup_list);
+
+		if (!dev->wakeup.flags.valid
+		    || sleep_state > (u32) dev->wakeup.sleep_state
+		    || !(device_may_wakeup(&dev->dev)
+		        || dev->wakeup.prepare_count))
+			continue;
+
+		acpi_set_gpe_wake_mask(dev->wakeup.gpe_device, dev->wakeup.gpe_number,
+				ACPI_GPE_DISABLE);
+
+		if (device_may_wakeup(&dev->dev))
+			acpi_disable_wakeup_device_power(dev);
+	}
+}
+
+int __init acpi_wakeup_device_init(void)
+{
+	struct list_head *node, *next;
+
+	mutex_lock(&acpi_device_lock);
+	list_for_each_safe(node, next, &acpi_wakeup_device_list) {
+		struct acpi_device *dev = container_of(node,
+						       struct acpi_device,
+						       wakeup_list);
+		if (device_can_wakeup(&dev->dev)) {
+			/* Button GPEs are supposed to be always enabled. */
+			acpi_enable_gpe(dev->wakeup.gpe_device,
+					dev->wakeup.gpe_number);
+			device_set_wakeup_enable(&dev->dev, true);
+		}
+	}
+	mutex_unlock(&acpi_device_lock);
+	return 0;
+}