Jetson Orin Nano: Issues with USB VBUS Detection and GPIO Configuration

Issue Overview

Users are encountering issues related to USB VBUS detection and GPIO configuration on the Jetson Orin Nano Developer Kit. Specifically, users have reported that certain GPIO pins intended for USB VBUS detection are marked as "used," preventing their functionality. This situation arises when attempting to connect multiple devices, leading to confusion over the proper configuration and usage of the GPIO pins.

Relevant Hardware and Software Specifications

• Device: Jetson Orin Nano Developer Kit (8GB)
• Connection: Custom carrier board with USB ports configured for various applications.
• JetPack Version: Not explicitly mentioned.

Symptoms

• Users report that GPIO pins intended for USB VBUS detection are marked as "used" in the system.
• Attempts to access or configure these GPIO pins result in errors indicating that the device or resource is busy.
• Inability to detect USB devices connected to the specified GPIO pins.

Possible Causes

1. GPIO Pin Configuration Conflicts: The GPIO pins may already be in use by other processes or hardware components, preventing their use for USB VBUS detection.
2. Driver or Kernel Issues: There may be bugs or conflicts in the drivers that affect GPIO functionality.
3. Incorrect Device Tree Configuration: The device tree may not correctly reflect the intended use of the GPIO pins for USB VBUS detection, leading to misconfiguration.
4. Hardware Connections: Physical connections or wiring issues could prevent proper communication over the configured GPIO pins.

Troubleshooting Steps, Solutions & Fixes

Step-by-Step Instructions

1. Check GPIO Usage:

   • Use the following command to check which processes are using the GPIO pins:

     sudo gpioinfo 1
     

   • Identify if the pins are marked as "used" and by which process.

2. Inspect Device Tree Settings:

   • Review and modify the device tree source files if necessary to ensure that the intended GPIO pins are configured correctly for USB VBUS detection.

3. Check Driver Status:

   • Use lsmod to check if the necessary drivers for USB and GPIO are loaded:

     lsmod | grep nvidia
     

4. Test with Different Configurations:

   • If possible, try using different GPIO pins that are not currently in use to see if they can be configured for USB VBUS detection.

5. Consult Documentation and Community Resources:

   • Refer to NVIDIA’s official documentation for guidance on configuring GPIOs and troubleshooting common issues related to USB connections.

6. Use Serial Console Logs:

   • Connect a serial console to gather more detailed logs during boot attempts, which can provide insights into where conflicts may arise.

Recommended Fixes

• Users have successfully resolved similar issues by ensuring correct configurations in the device tree and verifying physical connections.
• Modifying pinmux settings through device tree files has also been highlighted as a necessary step for proper functionality.

Best Practices for Future Prevention

• Document all configurations and changes made during development for future reference.
• Regularly check NVIDIA forums and documentation for updates regarding known issues with specific JetPack versions.

Unresolved Aspects and Further Investigation

• Users continue to seek clarity on how to effectively manage pinmux settings without extensive kernel modifications.
• There may be additional debugging steps required that are not fully documented in existing resources.

By following these troubleshooting steps and solutions, users can effectively address issues related to USB VBUS detection and GPIO configuration on their Jetson Orin Nano platform while ensuring compatibility with their hardware setups.