What is DisplayPort? DisplayPort is a digital display and data transfer interface developed by the Video Electronics Standards Association (VESA) in 2006. Like its contemporary competitors, HDMI and Thunderbolt, it is a composite format capable of carrying video, audio, and data simultaneously.
Locked Home Screen. One meaning of the term locked iPhone refers to an iPhone with a locked home screen. All iPhones have a lock feature that allows a user to lock his home screen when the phone is not in use to prevent him from accidentally activating the touch screen while the phone is in his pocket.
If you're in this situation, you're encountering a relatively new feature of Apple's Find My iPhone service called Activation Lock. Activation Lock is a security measure that Apple added to Find My iPhone to deal with the rash of iPhone thefts.