diff -r 000000000000 -r 6474c204b198 hal/HalSensor.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hal/HalSensor.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,77 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set sw=2 ts=8 et ft=cpp : */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef __HAL_SENSOR_H_
+#define __HAL_SENSOR_H_
+
+#include "mozilla/Observer.h"
+
+namespace mozilla {
+namespace hal {
+
+/**
+ * Enumeration of sensor types.  They are used to specify type while
+ * register or unregister an observer for a sensor of given type.
+ */
+enum SensorType {
+  SENSOR_UNKNOWN = -1,
+  SENSOR_ORIENTATION,
+  SENSOR_ACCELERATION,
+  SENSOR_PROXIMITY,
+  SENSOR_LINEAR_ACCELERATION,
+  SENSOR_GYROSCOPE,
+  SENSOR_LIGHT,
+  NUM_SENSOR_TYPE
+};
+
+class SensorData;
+
+typedef Observer<SensorData> ISensorObserver;
+
+/**
+ * Enumeration of sensor accuracy types.
+ */
+enum SensorAccuracyType {
+  SENSOR_ACCURACY_UNKNOWN = -1,
+  SENSOR_ACCURACY_UNRELIABLE,
+  SENSOR_ACCURACY_LOW,
+  SENSOR_ACCURACY_MED,
+  SENSOR_ACCURACY_HIGH,
+  NUM_SENSOR_ACCURACY_TYPE
+};
+
+class SensorAccuracy;
+
+typedef Observer<SensorAccuracy> ISensorAccuracyObserver;
+
+}
+}
+
+#include "ipc/IPCMessageUtils.h"
+
+namespace IPC {
+  /**
+   * Serializer for SensorType
+   */
+  template <>
+  struct ParamTraits<mozilla::hal::SensorType>:
+    public ContiguousEnumSerializer<
+             mozilla::hal::SensorType,
+             mozilla::hal::SENSOR_UNKNOWN,
+             mozilla::hal::NUM_SENSOR_TYPE> {
+  };
+
+  template <>
+  struct ParamTraits<mozilla::hal::SensorAccuracyType>:
+    public ContiguousEnumSerializer<
+             mozilla::hal::SensorAccuracyType,
+             mozilla::hal::SENSOR_ACCURACY_UNKNOWN,
+             mozilla::hal::NUM_SENSOR_ACCURACY_TYPE> {
+
+  };
+} // namespace IPC
+
+#endif /* __HAL_SENSOR_H_ */