Do I need to test my USB product for USB-IF compliance?
In order for a USB product to have the right to license the USB logo and be added to the USB IF Integrators List, the product must pass USB-IF compliance testing. The USB.org developers page provides a full description of the tests and procedures:
If your product does not require the use of the USB logo in its packaging or documentation, USB-IF compliance testing is not required.
All Silicon Labs USB devices have passed USB compliance testing. This includes the CP210x USB-to-UART bridges and the general purpose USB MCUs. The Silicon Labs USB devices were tested using the evaluation and target boards. USB-IF compliance testing certifies products at a system-level and not a device-level and so any unique product created using a Silicon Labs USB device must be retested.