PhoneWindowManage.java :
KEYCODE_POWER -> interceptPowerKeyDown(…) -> wakeUpFromPowerKey() -> wakeUp() -> mPowerManager.wakeUp(…)
PowerManagerService:
wakeUp(..) -> wakeUpInternal(…) -> updatePowerStateLock -> updateDisplayPowerStateLocked -> mDisplayManagerInternal.requestPowerState(…)
DiaplayPowerController.java:
requestPowerState(…) -> sendUpdatePowerStateLocked() -> sendMessage(MSG_UPDATE_POWER_STATE) -> updatePowerState() -> animateScreenStateChange -> setScreenState()
picture from other person’s blog
