Reland of [sensors] Ambient light sensor implementation for ChromeOS and Linux.

device/generic_sensor/linux/sensor_data_linux.cc

Index: device/generic_sensor/linux/sensor_data_linux.cc
diff --git a/device/generic_sensor/linux/sensor_data_linux.cc b/device/generic_sensor/linux/sensor_data_linux.cc
new file mode 100644
index 0000000000000000000000000000000000000000..08285512d6cd8c45b6511e549b183b397ae5006f
--- /dev/null
+++ b/device/generic_sensor/linux/sensor_data_linux.cc
@@ -0,0 +1,52 @@
+// 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.
+
+#include "device/generic_sensor/linux/sensor_data_linux.h"
+#include "device/sensors/public/cpp/device_sensors_consts.h"
+
+namespace device {
+
+namespace {
+
+using mojom::SensorType;
+
+const base::FilePath::CharType* kSensorsBasePath =
+    FILE_PATH_LITERAL("/sys/bus/iio/devices");
+
+void InitAmbientLightSensorData(SensorDataLinux* data) {
+  std::vector<std::string> file_names{
+      "in_illuminance0_input", "in_illuminance_input", "in_illuminance0_raw",
+      "in_illuminance_raw"};
+
+  data->sensor_file_names.push_back(std::move(file_names));
+  data->reporting_mode = mojom::ReportingMode::ON_CHANGE;
+  data->default_configuration =
+      PlatformSensorConfiguration(kDefaultAmbientLightFrequencyHz);
+}
+
+}  // namespace
+
+SensorDataLinux::SensorDataLinux() : base_path_sensor_linux(kSensorsBasePath) {}
+
+SensorDataLinux::~SensorDataLinux() = default;
+
+SensorDataLinux::SensorDataLinux(const SensorDataLinux& other) = default;
+
+bool InitSensorData(SensorType type, SensorDataLinux* data) {
+  DCHECK(data);
+
+  switch (type) {
+    case SensorType::AMBIENT_LIGHT: {
+      InitAmbientLightSensorData(data);
+      break;
+    }
+    default: {
+      NOTIMPLEMENTED();
+      return false;
+    }
+  }
+  return true;
+}
+
+}  // namespace device