About USB 3.1 HUB design on custom board

I’m designing our board with Xavier NX module. On the devkit, the HUB chip is a Realtek RTS5489-GR ( the public one is RTS5420?). But the doc about the chip is not easily to get for me. So, my goal is to use a more publicly available one, such those from TI, and use the devkit’s image without much driver coding. I have several questions:

  1. I’ve never use Realtek’s USB hub chip. But in TI’s chips, they states they need no special driver to run with OS, all should be handled by USB protocol. Though their chips have external configuration interfaces, they may be bypassed, and the default configuration should work. So, may the guys from Nvidia confirm me that a chip from TI with no special driver needed will work with Xavier’s image?
  2. And for the Realtek one, are there any special driver needed to run the chip? As there are at least two external interfaces to the chip, one flash and one I2C bus. What the driver/chip do to these two interfaces? What content is stored in the flash?

Thanks.

Hi,

There is no specific driver needed even on the Realtek hub. The Realtek hubs work with default driver in Linux.
We cannot comment over the TI hub since there is no experience of bringing up their hub.

It is possible that the hub requires extra firmware and that needs to be provided by the vendor.

I see the I2C is shared with CAM, and with address 7’h6A. Is this interface necessary? What about remove this interface? Will the hub still work well?

Thanks.

It is necessary.

I’m a bit confused now. If the I2C interface is necessary, there must some special settings outside of the standard USB protocols. Of course, the Linux may have built in support for this chip. But how Linux know which I2C and which address the HUB chip use? I’m not very family with Linux drivers. May you tell more?

Thanks.

You can find the HUB reference design including I2C and address in P3509 schematic in DLC. The other option than the reference design is not validated.