[sensors][CrOS/Linux] Implementation of motion sensors for CrOS/Linux platforms

device/generic_sensor/generic_sensor_consts.h

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef DEVICE_GENERIC_SENSOR_GENERIC_SENSOR_CONSTS_H_
+#define DEVICE_GENERIC_SENSOR_GENERIC_SENSOR_CONSTS_H_
+
+namespace device {
+
+// Required for conversion from G/s^2 to m/s^2
+constexpr double kMeanGravity = 9.80665;
+
+// Required for conversion from deg/s^2 to rad/s^2
+constexpr double kRadiansInDegreesPerSecond = M_PI / 180.0;

[Reilly Grant (use Gerrit), 2016/11/10 16:53:17]

Include the header M_PI is defined in.

[maksims (do not use this acc), 2016/11/11 08:52:02]

Done.

+
+// Required for conversion from Gauss to uT.
+constexpr double kMicroteslaInGauss = 100.0;
+
+// Default rate for returning value of the ambient light sensor.
+constexpr int kDefaultAmbientLightFrequencyHz = 5;
+
+// Default rate for returning value of the accelerometer sensor.
+constexpr int kDefaultAccelerometerFrequencyHz = 10;
+
+// Default rate for returning value of the gyroscope sensor.
+constexpr int kDefaultGyroscopeFrequencyHz = 10;
+
+// Default rate for returning value of the magnetometer sensor.
+constexpr int kDefaultMagnetometerFrequencyHz = 10;
+
+// ChromeOS kernel version, when axes were changed to XYZ. Before 3.18,
+// they were YXZ.
+const char kChangedAxisKernelVersion[] = "3.18.0";

[Reilly Grant (use Gerrit), 2016/11/10 16:53:17]

Constant string values should be declared in header files but have their value
defined in a C++ file so that storage is only allocated in a single location.
Since this value is only useful to the Linux sensor implementation it should
probably just be defined in sensor_data_linux.cc.

[maksims (do not use this acc), 2016/11/11 08:52:02]

Oops. I've put this here by accident with other consts.

+
+}  // namespace device
+
+#endif  // DEVICE_GENERIC_SENSOR_GENERIC_SENSOR_CONSTS_H_