RM520N-GL PCIe driver and AT command interface

IoT Modules 5G Module
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Hi, I’m using a RM520N-GL modem, it’s connected over PCIe to a custom design. I’m using Linux kernel version 6.1.36. So far, I have the device working with oFono and mbimcli via mhi_pci_generic driver, but there are no virtual serial ports for executing AT commands. What is required to expose these virtual serial ports so I can run AT commands?
Thanks,
Doug Burrell

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Connect M.2 5G modem to PCI and USB at the same time is supported right? And how configure. (RM551E-GL, RM520N-GL etc.)
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Linux PCIE Driver for RM520N-GL - IoT Modules / 5G Module - Quectel Forums

Could you show
mmcli -m 0

I don’t know whether the mhi_pcie_generic support the AT port. Normally we would like to try the Quectel driver pcie_mhi.

RM520N includes different kinds, some module is working for laptop and might do not support AT port.

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I don’t currently have modemmanager installed on this device but I have mbimcli, here’s a similar command and its output using mbimcli:
mbimcli -d /dev/wwan0mbim0 --query-device-caps
[/dev/wwan0mbim0] Device capabilities retrieved:
Device type: ‘embedded’
Cellular class: ‘gsm’
Voice class: ‘no-voice’
SIM class: ‘removable’
Data class: ‘umts, hsdpa, hsupa, lte, custom’
SMS caps: ‘pdu-receive, pdu-send’
Ctrl caps: ‘reg-manual’
Max sessions: ‘15’
Custom data class: ‘5G/TDS’
Device ID: ‘867922070007155’
Firmware info: ‘RM520NGLAAR03A04M4G’
Hardware info: ‘RM520N-GL’

Could you send me the Quectel “pcie_mhi” driver or tell me where I can get the latest that will be compatible with Linux kernel 6.1.36?

Thanks,
Doug Burrell

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A teammate of mine has already been working with the pcie_mhi driver, and he has not been able to get any virtual serial ports exposed. Does the model of the RM520N that we’re using not support virtual serial ports? Additionally, he was unable to get the pcie_mhi driver to work with oFono, which is what we use to control our cell interface. Is there any information you can provide specific to getting the pcie_mhi driver to expose virtual serial ports?
Thanks,
Doug Burrell

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Do you know when Quectel will include the pcie_mhi driver in the mainline Linux kernel?

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@dooglas77
Please check the Quectel_Linux_PCIE_MHI_Driver_V1.3.8.
But it might not support the mbimcli or mmcli by default.
With pcie_mhi, normally you should be able to see the
/dev/mhi_DUN which is used for AT command.

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Thank you, I received the driver. I will work with this and will let you know if I have any issues.

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Does this work fine for you !?