> > > > > > > > > > > > You may use connect bit at portsc since VBUS may not connect to SoC. > > > > > > By this way, disconnect can be decided but connect is a problem in > > > current driver, as controller was stopped in low power mode so can't > > > detect connection from host, unless we also update this behavior too. > > > > > > > For connection, if current role is USB_ROLE_NONE, you may start device mode. > > This is assuming set role only can be called one time between disconnect and > connect to host, this may not always true, but this can be resolved, I think > we need > handle the case device mode is started but connection does not happen, so the > gadget need be stopped and enter low power mode again, if this approach is OK > to > you, I will go in this direction for my v2. > After thinking more, I think Type-C tcpm code should set usb_role correctly, it knows physical connection status well, and there are already USB_ROLE_NONE references at tcpm now. Depending on USB device driver workaround to know USB_ROLE_NONE is not a good solution. Look at another USB role driver, intel-xhci-usb-role-switch.c, it could also get USB_ROLE_NONE state.
Peter
