Method and system for detecting displayport source device connections to sink device

Methods and systems are disclosed for detecting DisplayPort (DP) source device connection to sink devices. When the DP link is active, no measurements are made to determine source device connections. When a DP link is not active, a signal line for the auxiliary channel for a DP connection is measured to determine if a source device is connected. More particularly, the auxiliary channel is a differential auxiliary channel, and the positive signal line is measured to make the determination of whether a source device is connected. Still further, an indication is made that a source device is connected if the positive signal line is at a low level, and an indication is made that a source device is not connected if the positive signal line is at a high level.