I have a question about USB-C - USB 3.0 Design. I have asked to some manufacturers (Renesas, Texas Instruments) if their PCIE to USB controllers support Dual Role Data but they told to me that that feature is not supported by their products (TUSB73x0 and UPD720201). There are not much other alternatives.
On Texas Instruments forums, a moderator told to me that I need a PHY USB 3.0 but I need to convert from PCIE lines. Is there any device that could do that?
To have a USB-C DRD port, you need to have both Host Controller, and some Device controller at least. PCIe add-on cards predominantly are USB Hosts. To have a device, you have to dedicate a lot of silicon area for device functionality, and to define what your device will do, which USB class to be in. In portable device world the devices usually are MTP (Media Transfer Protocol) and/or PTP (Picture Transfer Protocol). True, the design must have USB3 PHY, and you need to multiplex/switch host traffic with device traffic at PHY interface (PIPE3 or else); PCIe lines have nothing to do with this. The MUX can be also done at analog level, between two PHYs (host and device) and USB-C connector.
Is there a device that can do that? Most likely you will need to get some SOC (Qualcomm or Samsung) with DRD (aka OTG) functionality, and slap a PCIe-PCIe bridge to it, or something. It will be a substantial effort.
