Hi, I’m the Toradex AI Assistant.
I might make mistakes or occasionally get you wrong. Our support team will step in if needed.
To help you get the most accurate guidance, could you let me know which OS and version you’re using? You can get this information by running the tdx-info command on your device. This will help me provide more specific troubleshooting steps for your setup.
For reference on getting system information, please see: tdx-info command documentation
Based on your logs and the error messages you’re seeing, this appears to be a ModemManager configuration issue specific to how the Sierra EM9291 ports are being handled. The key error is:
Failed to find a net port in the MBIM modem
Analysis of Your Issue
Your modem is being detected correctly by the MHI (Modem Host Interface) driver and creating the expected WWAN ports (1). However, ModemManager is failing to properly handle the port configuration for this specific modem model.
ModemManager Support
ModemManager is available on Torizon OS out-of-the-box and provides support for mobile broadband devices through the mmcli command-line tool (1). ModemManager uses libqmi and libmbim to communicate over Qualcomm MSM Interface (QMI) and Mobile Interface Broadband Model (MBIM) protocols (1).
Troubleshooting Steps
1. Check Port Detection
First, verify which ports are actually available:
ls -la /dev/wwan*
2. Manual ModemManager Configuration
Try restarting ModemManager with additional debugging:
systemctl stop ModemManager
ModemManager --debug --log-level=DEBUG
3. Check Network Interface
The error suggests ModemManager cannot find the network interface. Check if a network interface was created:
ip link show | grep wwan
Sierra EM9291 Compatibility
Based on community discussions, the Sierra EM9291 is not officially listed as a compatible peripheral for Toradex modules (2). The modem detection issues you’re experiencing have been reported by other users, where the device is detected via PCIe but fails to properly enumerate with ModemManager (2).
Alternative Approaches
1. Custom Device Tree Configuration
Since this modem isn’t officially supported, you may need custom device tree overlays to properly configure the PCIe interface and port mappings.
2. Manual Port Configuration
You might need to manually configure the WWAN ports or create udev rules to properly map the device interfaces.
3. Consider Supported Alternatives
For production use, consider using modems from the Peripheral Database that have been tested with Toradex modules (3).
Once you provide your OS version information, I can give you more specific guidance for your platform.
Best regards, Toradex AI Assistant.
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