USB2 Device Only on Custom Hardware

Issue Overview

Users are experiencing difficulties in enabling USB2 device mode on custom carrier boards designed for the Nvidia Jetson Orin Nano Dev board. The primary symptoms include:

• Inability to get USB2 device functionality working as intended.
• Confusion regarding the necessary modifications to the device tree to accommodate custom hardware configurations.
• Specific context involves users attempting to adapt their designs based on the reference design of the p3768 devkit board, which utilizes a Type-C I2C controller connected to GPIO00.

The issue arises during the setup phase, particularly when users try to implement USB2 device mode without recompiling the device tree. This problem is consistent among several users who have followed the product design guide for USB2 devices but are unsure about the integration of their custom hardware with the existing software architecture.

The impact of this problem is significant, as it prevents users from utilizing USB2 functionality, which is crucial for many applications relying on USB connectivity.

Possible Causes

Several potential causes have been identified for this issue:

• Hardware Incompatibilities or Defects: If the custom carrier board does not align with the specifications outlined in the product design guide, it may lead to failures in USB2 functionality.

• Software Bugs or Conflicts: Existing software may not support the custom hardware configuration, leading to conflicts that prevent USB2 device mode from functioning correctly.

• Configuration Errors: Incorrect settings in the device tree or other configuration files may result in improper initialization of USB devices.

• Driver Issues: The drivers responsible for managing USB connections may not be compatible with the custom hardware setup.

• Environmental Factors: Power supply issues or temperature extremes could affect performance and lead to unexpected behavior.

• User Errors or Misconfigurations: Misunderstandings about how to properly configure the device tree or hardware connections can lead to failure in enabling USB2 mode.

Troubleshooting Steps, Solutions & Fixes

To address the issue of enabling USB2 device mode on custom hardware, follow these troubleshooting steps and solutions:

1. Verify Hardware Design:

   • Ensure that your custom carrier board adheres strictly to the specifications outlined in the product design guide for USB2 devices.
   • Check for any discrepancies in component placement and connections.

2. Modify Device Tree:

   • It is necessary to update the device tree (DTS) for your custom hardware. This involves:
     • Accessing the JetsonModuleAdaptationAndBringUp documentation for guidance on modifying and recompiling your DTS.
     • Using a terminal command to recompile your device tree blob (DTB):

       dtc -I dts -O dtb -o your_device_tree.dtb your_device_tree.dts
       

   • Note that using a device tree generation spreadsheet alone will not suffice; it only assists with pinmux configurations and does not encompass driver information required for USB functionality.

3. Check Kernel Configuration:

   • Ensure that your kernel is configured correctly to support USB devices. This may involve checking kernel modules related to USB support.

4. Test with Reference Design:

   • If possible, compare your custom hardware’s performance with that of a reference design (like the p3768 devkit) to identify any differences in behavior.

5. Gather System Information:

   • Use commands like lsusb and dmesg to gather information about connected devices and any error messages that may provide insight into what is failing during initialization.

6. Consult Documentation:

   • Review relevant documentation for driver updates or firmware upgrades that may address compatibility issues with your custom hardware.

7. Best Practices:

   • Always back up your current configurations before making changes.
   • Document any modifications made to assist with future troubleshooting efforts.

8. Community Support:

   • Engage with community forums or Nvidia support if problems persist after following these steps, as others may have encountered similar issues and found solutions.

By following these steps, users should be able to diagnose and resolve issues related to enabling USB2 device mode on their custom hardware setups effectively.