1. Could you please let me know which application you are referring to? Is it EMCA cable?
2. If your question is based on EMCA cable, the answer is, you can add additional SVID and mode via Ez-PD configuration Utility.
3. If your question is based on CCG2 notebook, the answer is yes, you can add the customize Alternate mode via Ez-PD configuration Utility and CCG2 SDK (download link: https://www.cypress.com/documentation/software-and-drivers/ez-pd-sdk-v302-ccg2-all-applications-ccg3-cable-adapter ). You can refer the DisplayPort Alt Mode (SVID=0xFF01) for your customization.
We are looking at developing our cable eco-system around the USB-C technology. It's obviously not USB-C, since that has a very specific meaning as defined by the USBIF organization. We do not use the flippable connector, rather a mil-spec connector. We don't plug into USB-C devices on the other end either.
Rather, we want to leverage the PD modes and the CCx/SBUx/AltMode-TX-RX capabilities. I am trying to determine the feasibility of using AltMode identification at the UFP (which in our case all resides "in the cable"). Based on the custom AltModes programmed into the cable UFP, the host DFP would know what kind of adaptor cable is attached and multiplex the SBUx and TX/RX lines appropriately.
We are not worried about compatibility outside our own ecosystem, since consumer USB-C devices aren't going to have a custom rugged MIL-circular interface connector.
I asked the question first partially because it's difficult to get random SDK tools installed in a corporate managed IT environment. If you are sure that we can specify whatever Alt-Mode identifiers that we want, then I will look to get the tools installed.
I am very sure that you can refer the DisplayPort Alt mode to customize your Alt mode. If you are not going to compatibility outside ecosystem, recommend you use CCG3 into your design. Since the SDK for CCG3 have demonstrated DisplayPort DFP_U and UFP_D with the firmware CYPD3125-40LQXI_notebook and CYPD3120-40LQXI_dp_dongle.