USB2514 - Do I need to enable battery charging on downstream ports if the USB devices are bus-powered?
This setting is not related to bus-power or self-power supply options. Enabling battery charging (through a pull-up resistor added onto the PRTPWR pin) means to enable the downstream signal handshake for battery charging. In this way, the USB downstream device knows that it can drag high current (up to 1.5 A) from the USB downstream bus.