SLVSD02E March 2015 – August 2021 TPS65982
To enable DisplayPort HPD signaling through PD messaging, two GPIO pins (GPIO4, GPIO5) are used as the HPD input and output. When events occur on this pins during a DisplayPort connection through the Type-C connector (configured in firmware), hardware timers trigger and interrupt the digital core to indicated needed PD messaging. Table 9-5 shows each I/O function when GPIO4/5 are configured in HPD mode. When HPD is not enabled via firmware, both GPIO4 and GPIO5 remain generic GPIO and may be programmed for other functions. Figure 9-42 and Figure 9-43.
|HPD (Binary) Configuration||GPIO4||GPIO5|
|00||HPD TX||Generic GPIO|
|01||HPD RX||Generic GPIO|
|10||HPD TX||HPD RX|
|11||HPD TX/RX (bidirectional)||Generic GPIO|