rockchip: radxa_rock-3b has disabled USB controller fd880000

Describe the bug

On a Radxa ROCK 3B (RK3568), one of the USB controllers is disabled in the OpenWrt device tree.

The affected controller is:

usb@fd880000

Its device-tree node has:

compatible = "generic-ehci"; reg = <0x00 0xfd880000 0x00 0x40000>; phys = <0x18>; phy-names = "usb"; status = "disabled";

The corresponding USB2 PHY host port is also disabled:

usb2phy@fe8b0000 { ... host-port { ... phandle = <0x18>; status = "disabled"; }; };

As a result, OpenWrt does not create a platform device for fd880000.usb.

OpenWrt version

r33051-f5dae5ece4

OpenWrt release

25.12.5

OpenWrt target/subtarget

rockchip/armv8

Device

Radxa ROCK 3B

Image kind

Official downloaded image

Steps to reproduce

No response

Actual behaviour

The controller at fd880000 is not initialized by OpenWrt.

The other USB controllers are initialized normally. For example, the kernel reports working USB controllers including:

fcc00000.usb fd000000.usb fd800000.usb fd840000.usb

but there is no corresponding initialization of:

fd880000.usb

The SIM7600G-H modem connected to this controller is therefore not detected by OpenWrt.

The relevant USB modem drivers are present in the kernel, including:

cdc_wdm usbserial_generic cdc_ether cdc_ncm qmi_wwan rndis_host cdc_mbim option Comparison with Debian

The exact same hardware and USB modem are detected correctly when running Debian on the ROCK 3B.

This indicates that the problem is not related to the physical USB port, modem, cable, or modem drivers.

Device tree investigation

The live OpenWrt device tree contains:

usb@fd800000 usb@fd840000 usb@fd880000 usb@fd8c0000 usb@fd000000 usb@fcc00000

However:

/sys/firmware/devicetree/base/usb@fd880000/status

contains:

disabled

and:

/sys/firmware/devicetree/base/usb@fd000000/status

contains:

okay

The fd880000 controller therefore never becomes a platform device.

Possible workaround

The controller and its PHY host port appear to become usable when changing both device-tree nodes from:

status = "disabled";

to:

status = "okay";

Specifically:

usb@fd880000 { ... status = "okay"; };

and:

usb2phy@fe8b0000 { ... host-port { ... status = "okay"; }; };

This is currently being tested as a device-tree workaround.

Expected behaviour

All USB controllers that are physically available and usable on the Radxa ROCK 3B should be enabled in the device tree, unless there is a documented hardware/design reason for disabling fd880000.

Additional info

The board is officially supported by OpenWrt as radxa_rock-3b.

The issue is particularly relevant for devices connected to the USB controller at fd880000, such as the SIM7600G-H LTE modem described above.

Diffconfig

Terms

• I am reporting an issue for OpenWrt, not an unsupported fork.