Use chromeos accelerometer reader and support only lid accelerometer.

athena/system/orientation_controller.cc

 // Copyright 2014 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.
 
 #include "athena/screen/public/screen_manager.h"
 #include "athena/system/orientation_controller.h"
 #include "base/bind.h"
 #include "base/files/file_path_watcher.h"
 #include "base/files/file_util.h"
 #include "base/message_loop/message_loop.h"
 #include "base/task_runner.h"
 
 namespace athena {
 
 namespace {
 
-// Path of the socket which the sensor daemon creates.
-const char kSocketPath[] = "/dev/sensors/orientation";
-
 // Threshold after which to rotate in a given direction.
 const int kGravityThreshold = 6.0f;
 
-// Minimum delay before triggering another orientation change.
-const int kOrientationChangeDelayNS = 500000000;
-
-enum SensorType {
-  SENSOR_ACCELEROMETER,
-  SENSOR_LIGHT,
-  SENSOR_PROXIMITY
-};
-
-// A sensor event from the device.
-struct DeviceSensorEvent {
-  // The type of event from the SensorType enum above.
-  int32_t type;
-
-  // The time in nanoseconds at which the event happened.
-  int64_t timestamp;
-
-  union {
-    // Accelerometer X,Y,Z values in SI units (m/s^2) including gravity.
-    // The orientation is described at
-    // http://www.html5rocks.com/en/tutorials/device/orientation/.
-    float data[3];
-
-    // Ambient (room) temperature in degrees Celcius.
-    float temperature;
-
-    // Proximity sensor distance in centimeters.
-    float distance;
-
-    // Ambient light level in SI lux units.
-    float light;
-  };
-};
-
 }  // namespace
 
-OrientationController::OrientationController()
-    : DeviceSocketListener(kSocketPath, sizeof(DeviceSensorEvent)),
-      last_orientation_change_time_(0),
-      shutdown_(false) {
-  CHECK(base::MessageLoopForUI::current());
-  ui_task_runner_ = base::MessageLoopForUI::current()->task_runner();
+OrientationController::OrientationController() {
 }
 
 void OrientationController::InitWith(
-    scoped_refptr<base::TaskRunner> file_task_runner) {
-  file_task_runner_ = file_task_runner;
-  file_task_runner->PostTask(
-      FROM_HERE,
-      base::Bind(&OrientationController::WatchForSocketPathOnFILE, this));
+    scoped_refptr<base::TaskRunner> blocking_task_runner) {
+  accelerometer_reader_.reset(
+      new chromeos::AccelerometerReader(blocking_task_runner, this));
 }
 
 OrientationController::~OrientationController() {
 }
 
 void OrientationController::Shutdown() {
-  CHECK(file_task_runner_.get());
-  StopListening();
-  file_task_runner_->PostTask(
-      FROM_HERE,
-      base::Bind(&OrientationController::ShutdownOnFILE, this));
+  accelerometer_reader_.reset();
 }
 
-void OrientationController::ShutdownOnFILE() {
-  shutdown_ = true;
-  watcher_.reset();
-}
-
-void OrientationController::WatchForSocketPathOnFILE() {
-  CHECK(base::MessageLoopForIO::current());
-  if (base::PathExists(base::FilePath(kSocketPath))) {
-    ui_task_runner_->PostTask(FROM_HERE,
-        base::Bind(&OrientationController::StartListening, this));
-  } else {
-    watcher_.reset(new base::FilePathWatcher);
-    watcher_->Watch(
-        base::FilePath(kSocketPath),
-        false,
-        base::Bind(&OrientationController::OnFilePathChangedOnFILE, this));
-  }
-}
-
-void OrientationController::OnFilePathChangedOnFILE(const base::FilePath& path,
-                                                    bool error) {
-  watcher_.reset();
-  if (error || shutdown_)
+void OrientationController::HandleAccelerometerUpdate(
+    const ui::AccelerometerUpdate& update) {
+  if (!update.has(ui::ACCELEROMETER_SOURCE_SCREEN))
     return;
 
-  ui_task_runner_->PostTask(FROM_HERE,
-      base::Bind(&OrientationController::StartListening, this));
-}
-
-void OrientationController::OnDataAvailableOnFILE(const void* data) {
-  const DeviceSensorEvent* event =
-      static_cast<const DeviceSensorEvent*>(data);
-  if (event->type != SENSOR_ACCELEROMETER)
-    return;
-
-  float gravity_x = event->data[0];
-  float gravity_y = event->data[1];
+  float gravity_x = update.get(ui::ACCELEROMETER_SOURCE_SCREEN).x();
+  float gravity_y = update.get(ui::ACCELEROMETER_SOURCE_SCREEN).y();
   gfx::Display::Rotation rotation;
   if (gravity_x < -kGravityThreshold) {
     rotation = gfx::Display::ROTATE_270;
   } else if (gravity_x > kGravityThreshold) {
     rotation = gfx::Display::ROTATE_90;
   } else if (gravity_y < -kGravityThreshold) {
     rotation = gfx::Display::ROTATE_180;
   } else if (gravity_y > kGravityThreshold) {
     rotation = gfx::Display::ROTATE_0;
   } else {
     // No rotation as gravity threshold was not hit.
     return;
   }
 
-  if (rotation == current_rotation_ ||
-      event->timestamp - last_orientation_change_time_ <
-          kOrientationChangeDelayNS) {
+  if (rotation == current_rotation_)
     return;
-  }
 
-  last_orientation_change_time_ = event->timestamp;
   current_rotation_ = rotation;
-  ui_task_runner_->PostTask(FROM_HERE,
-      base::Bind(&OrientationController::RotateOnUI, this, rotation));
-}
-
-void OrientationController::RotateOnUI(gfx::Display::Rotation rotation) {
-  ScreenManager* screen_manager = ScreenManager::Get();
-  // Since this is called from the FILE thread, the screen manager may no longer
-  // exist.
-  if (screen_manager)
-    screen_manager->SetRotation(rotation);
+  ScreenManager::Get()->SetRotation(rotation);
 }
 
 }  // namespace athena