Hi Pedro,
In my opinion TI doesn't have special circuit for I2S -> USB conversion. You can create it by combination of USB CODEC PCM2902C which has S/PDIF input and DIT4096 which converts I2S to the S/PDIF. This solution support up to 16bit/48kHz. If you want more it will be probably possible with some DSP like TMS320C5533 but I don't know them.
Best regards,
Pavel