| On Chrome OS, we want to dim the screen when the user is idle. To do this, |
| the power manager subscribes for idle notifications from XSync, and adjusts |
| the backlight based on whether or not the user is idle. |
| |
| Executable programs: |
| * backlight-tool (backlight-tool.cc) |
| Simple tool to get and set the brightness level of the display backlight. |
| * powerd (powerd.cc) |
| Upper power manager. Adjusts device status based on whether the |
| user is idle and on video activity indicator from the window manager. |
| This daemon is responsible for dimming the backlight or turning off the |
| screen based on user idle, and it is responsible for adjusting backlight |
| intensity based on user input and ambient light condition. The daemon also |
| monitors plug state (on ac or on battery) and battery state-of-charge. |
| * powerm (powerman_daemon.cc) |
| Lower power manager. Provides infrastructure for invoking suspend to RAM and |
| system shutdown. Handles input events for hall effect sensor (lid) and power |
| button. |
| * xidle-example (xidle-example.cc) |
| Prints console notifications when the user is and is not idle. |
| |
| Main Classes: |
| * AmbientLightSensor (ambient_light_sensor.{cc,h}) |
| Polls the ambient light sensor for current lighting conditions. |
| * Backlight (backlight.{cc,h}) |
| Get and set the brightness level of the display backlight. |
| * BacklightController (backlight_controller.{cc,h}) |
| Adjusts the backlight based on whether the user is idle. |
| * VideoDetector (video_detector.{cc,h}) |
| Polls the root window for video activity timestamp posted by the window |
| manager. Allows powerd to defer idle when video has been playing recently. |
| * XIdle (xidle.{cc,h}) |
| Receive notifications from the X Server when the user is marked as |
| idle, or as no longer idle |
| |
| Unit tests: |
| * idle_dimmer_unittest.cc: |
| Tests the BacklightController class. |
| * xidle_unittest.cc: |
| Tests the XIdle class with a real X server (or a virtual framebuffer). |
| |
| Autotests: |
| * hardware_Backlight |
| Verifies that backlight-tool can adjust brightness. |
| * power_Backlight |
| Verifies that adjusting the brightness with the backlight-tool changes the |
| amount of power used by the machine. |
| |
