ACPI / PM: Move routines for adding/removing device wakeup notifiers

ACPI routines for adding and removing device wakeup notifiers are
currently defined in a PCI-specific file, but they will be necessary
for non-PCI devices too, so move them to a separate file under
drivers/acpi and rename them to indicate their ACPI origins.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c
new file mode 100644
index 0000000..2d2e0bc
--- /dev/null
+++ b/drivers/acpi/device_pm.c
@@ -0,0 +1,91 @@
+/*
+ * drivers/acpi/device_pm.c - ACPI device power management routines.
+ *
+ * Copyright (C) 2012, Intel Corp.
+ * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as published
+ *  by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful, but
+ *  WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#include <linux/device.h>
+#include <linux/mutex.h>
+
+#include <acpi/acpi.h>
+#include <acpi/acpi_bus.h>
+
+static DEFINE_MUTEX(acpi_pm_notifier_lock);
+
+/**
+ * acpi_add_pm_notifier - Register PM notifier for given ACPI device.
+ * @adev: ACPI device to add the notifier for.
+ * @context: Context information to pass to the notifier routine.
+ *
+ * NOTE: @adev need not be a run-wake or wakeup device to be a valid source of
+ * PM wakeup events.  For example, wakeup events may be generated for bridges
+ * if one of the devices below the bridge is signaling wakeup, even if the
+ * bridge itself doesn't have a wakeup GPE associated with it.
+ */
+acpi_status acpi_add_pm_notifier(struct acpi_device *adev,
+				 acpi_notify_handler handler, void *context)
+{
+	acpi_status status = AE_ALREADY_EXISTS;
+
+	mutex_lock(&acpi_pm_notifier_lock);
+
+	if (adev->wakeup.flags.notifier_present)
+		goto out;
+
+	status = acpi_install_notify_handler(adev->handle,
+					     ACPI_SYSTEM_NOTIFY,
+					     handler, context);
+	if (ACPI_FAILURE(status))
+		goto out;
+
+	adev->wakeup.flags.notifier_present = true;
+
+ out:
+	mutex_unlock(&acpi_pm_notifier_lock);
+	return status;
+}
+
+/**
+ * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device.
+ * @adev: ACPI device to remove the notifier from.
+ */
+acpi_status acpi_remove_pm_notifier(struct acpi_device *adev,
+				    acpi_notify_handler handler)
+{
+	acpi_status status = AE_BAD_PARAMETER;
+
+	mutex_lock(&acpi_pm_notifier_lock);
+
+	if (!adev->wakeup.flags.notifier_present)
+		goto out;
+
+	status = acpi_remove_notify_handler(adev->handle,
+					    ACPI_SYSTEM_NOTIFY,
+					    handler);
+	if (ACPI_FAILURE(status))
+		goto out;
+
+	adev->wakeup.flags.notifier_present = false;
+
+ out:
+	mutex_unlock(&acpi_pm_notifier_lock);
+	return status;
+}