PM / Sleep: Add wake lock api wrapper on top of wakeup sources

Change-Id: Icaad02fe1e8856fdc2e4215f380594a5dde8e002
Signed-off-by: Arve Hjønnevåg <arve@android.com>
diff --git a/include/linux/wakelock.h b/include/linux/wakelock.h
new file mode 100644
index 0000000..f4a698a
--- /dev/null
+++ b/include/linux/wakelock.h
@@ -0,0 +1,67 @@
+/* include/linux/wakelock.h
+ *
+ * Copyright (C) 2007-2012 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ *
+ */
+
+#ifndef _LINUX_WAKELOCK_H
+#define _LINUX_WAKELOCK_H
+
+#include <linux/ktime.h>
+#include <linux/device.h>
+
+/* A wake_lock prevents the system from entering suspend or other low power
+ * states when active. If the type is set to WAKE_LOCK_SUSPEND, the wake_lock
+ * prevents a full system suspend.
+ */
+
+enum {
+	WAKE_LOCK_SUSPEND, /* Prevent suspend */
+	WAKE_LOCK_TYPE_COUNT
+};
+
+struct wake_lock {
+	struct wakeup_source ws;
+};
+
+static inline void wake_lock_init(struct wake_lock *lock, int type,
+				  const char *name)
+{
+	wakeup_source_init(&lock->ws, name);
+}
+
+static inline void wake_lock_destroy(struct wake_lock *lock)
+{
+	wakeup_source_trash(&lock->ws);
+}
+
+static inline void wake_lock(struct wake_lock *lock)
+{
+	__pm_stay_awake(&lock->ws);
+}
+
+static inline void wake_lock_timeout(struct wake_lock *lock, long timeout)
+{
+	__pm_wakeup_event(&lock->ws, jiffies_to_msecs(timeout));
+}
+
+static inline void wake_unlock(struct wake_lock *lock)
+{
+	__pm_relax(&lock->ws);
+}
+
+static inline int wake_lock_active(struct wake_lock *lock)
+{
+	return lock->ws.active;
+}
+
+#endif
diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig
index e8517b6..03203c9 100644
--- a/kernel/power/Kconfig
+++ b/kernel/power/Kconfig
@@ -28,6 +28,10 @@
 	  of suspend, or they are content with invoking sync() from
 	  user-space before invoking suspend.  Say Y if that's your case.
 
+config WAKELOCK
+	bool
+	default y
+
 config HIBERNATE_CALLBACKS
 	bool