Dwarf: RTL8821CU WiFi supported?

Developers
#1

Hi - Does anybody know if the RTL8821CU chipset is supported? Tried following the instructions on WiFi - MOD Wiki (moddevices.com) without any success:

[    0.583063] usb 1-1: New USB device found, idVendor=0bda, idProduct=c811, bcdDevice= 2.00
[    0.583083] usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[    0.583091] usb 1-1: Product: 802.11ac NIC
[    0.583097] usb 1-1: Manufacturer: Realtek
[    0.583103] usb 1-1: SerialNumber: 123456

…following the instructions ultimately results in: “A dependency job for dhcpcd-wlan0.service failed. See ‘journalctl -xe’ for details.”

Jan 01 02:23:03 moddwarf systemd[1]: Job sys-subsystem-net-devices-wlan0.device/start timed out.
Jan 01 02:23:03 moddwarf systemd[1]: Timed out waiting for device sys-subsystem-net-devices-wlan0.device.
Jan 01 02:23:03 moddwarf systemd[1]: Dependency failed for DHCP for wlan0.
Jan 01 02:23:03 moddwarf systemd[1]: Job dhcpcd-wlan0.service/start failed with result 'dependency'.
Jan 01 02:23:03 moddwarf systemd[1]: Dependency failed for WPA supplicant for wlan0.
Jan 01 02:23:03 moddwarf systemd[1]: Job wpa-supplicant-wlan0.service/start failed with result 'dependency'.
Jan 01 02:23:03 moddwarf systemd[1]: Job sys-subsystem-net-devices-wlan0.device/start failed with result 'timeout'.

I’ve tried the latest release candidate 1.13.0-RC1 which suggests it supports most BT/WiFi drivers out of the box (and appears to include modules for ‘rtlxxxu’, ‘rtl8192cu’ etc. within drivers/net/wireless/realtek which may or may not be relevant.).

Is there anything special I need to be doing here, other than buy another adaptor (specifically, I have this one: Foktech Wifi Dongle, AC600 802.11ac Dual Band 5GHz Mini Wireless Network USB Wifi Adapter

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#2

HI @CreativeLemming i experienced the same with a bluetooth/wifi combi dongle.
The bluetooth part works flawlessly but the wireless part is nit recognized
As far as i can tell there needs to be something integrated in the kernel.
Have a look here:

i was hoping that maybe with 1.13 there will be something working but no.
maybe @falkTX can do something because as far as i know there a lot of cheap wifi dongles with this chipset

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#3

Thanks @phil, I did see that, and also this one that appears to be updated more frequently (for 6.x kernel?)

…unfortunately not something I’d feel comfortable building/installing myself right now, unless there are any instructions on the wiki on how to get set up for this?

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#4

same here, i dont know how to get this into the kernel/dwarf.
is solved the problem with a different wifi dongle and a additional BL dongle.
one for all would be great, maybe we wait

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#5

Need to get my hands on one to test and fix whatever is needed, hard to do so without one.
Looking online that specific usb dongle is not available to buy from germany. So if you know other products with this exact chip/module, please do tell.

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#6

this one for example:

available in good old germany

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#7

Mines not a dual function device like Phil’s - mines actually reporting on my PC as RTL8811CU, the same as this one in stock on Amazon Germany:

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#8

Hi all, as noted in Bluetooth Dongles tested on MOD Devices, I have a T-P Link AC 600 (aka Archer T2UB Nano” combined Bluetooth 4.2/WiFi USB dongle) - the Bluetooth part works fine on my Dwarf but I have not been able to make the WiFi part work - I share my notes here in the hope that this is useful to someone, if for no other reason than to tell them not to buy this dongle for WiFi use.

I am running firmware v1.13.2.3174 on my Dwarf:

Linux moddwarf 6.1.15-rt7-moddwarf #10 SMP PREEMPT_RT Wed Jun 28 10:41:02 UTC 2023 aarch64 GNU/Linux

When I plug in the dongle, the following text appears in dmesg:

[  113.514220] usb 1-1.1: new high-speed USB device number 3 using ehci-platform
[  113.618442] usb 1-1.1: New USB device found, idVendor=0bda, idProduct=c820, bcdDevice= 2.00
[  113.618466] usb 1-1.1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[  113.618475] usb 1-1.1: Product: 802.11ac NIC
[  113.618481] usb 1-1.1: Manufacturer: Realtek
[  113.618487] usb 1-1.1: SerialNumber: 123456
[  113.629023] Bluetooth: hci0: RTL: examining hci_ver=08 hci_rev=000c lmp_ver=08 lmp_subver=8821
[  113.630483] Bluetooth: hci0: RTL: rom_version status=0 version=1
[  113.630509] Bluetooth: hci0: RTL: loading rtl_bt/rtl8821c_fw.bin
[  113.634572] Bluetooth: hci0: RTL: loading rtl_bt/rtl8821c_config.bin
[  113.636221] Bluetooth: hci0: RTL: cfg_sz 10, total sz 34926
[  114.132149] Bluetooth: hci0: RTL: fw version 0x75b8f098
[  114.198618] Bluetooth: MGMT ver 1.22

Note that the Bluetooth driver loads the rtl8821c firmware while I think the dongle really has an rtl8821au chipset. ( Realtek chipset page )

When following the instructions in the Wiki WiFi page

[root@moddwarf ~]# systemctl restart wpa-supplicant-wlan0 dhcpcd-wlan0
A dependency job for wpa-supplicant-wlan0.service failed. See 'journalctl -xe' for details.
A dependency job for dhcpcd-wlan0.service failed. See 'journalctl -xe' for details.

I note that it takes some time (maybe a minute or two) before the command provides any output.

The tail end of journalctl output is:

Jan 01 00:34:35 moddwarf systemd[1]: Timed out waiting for device sys-subsystem-net-devices-wlan0.device.
Jan 01 00:34:35 moddwarf systemd[1]: Dependency failed for DHCP for wlan0.
Jan 01 00:34:35 moddwarf systemd[1]: Job dhcpcd-wlan0.service/start failed with result 'dependency'.
Jan 01 00:34:35 moddwarf systemd[1]: Dependency failed for WPA supplicant for wlan0.
Jan 01 00:34:35 moddwarf systemd[1]: Job wpa-supplicant-wlan0.service/start failed with result 'dependency'.
Jan 01 00:34:35 moddwarf systemd[1]: Job sys-subsystem-net-devices-wlan0.device/start failed with result 'timeout'.

This all seems very similar to the output reported by @CreativeLemming although I note that his idProduct=c811 while mine is c820 so it is not exactly the same device.

Using dmesg | tail I do not see any new output at all, which surprises me. There is certainly no sign of any attempt to load firmware.

Reading around on other fora, I see now that I should perhaps have been a little more careful in my choice of dongle. In particular, it seems that multi-function BT/WiFi dongles are rather more problematic than single-function ones. So, just to be clear, while it would be cool if this worked (having a single, tiny dongle that allows both BT and WiFi access to the Dwarf seems pretty flexible) it is not a showstopper for me.

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#10

Here is how i managed to build and install the rtl8188eu wifi driver. It may (or may not) work with you…

You could follow the same path to build and install this GitHub - morrownr/8821cu: Linux Driver for USB WiFi Adapters that are based on the RTL8811CU, RTL8821CU and RTL8731AU Chipsets

It was a bit of pain because you must before build the docker image with the cross-environment which takes a long time

I don’t think my driver could would work for you, but If you want to give it a try, here you can find the module and the fw. Transfer them to the dwarf, copy the fw in /data/firmware and try manually loading the module with insmod (if you don’t know how to do it better don’t try :slight_smile: )

NOTE: I will not be responsible if this turns your dwarf in a ZOOM G1 or if it steals your girlfriend stratocaster

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#11

Thanks @Zavorra,

I am also not convinced that the 8821cu driver will work for me, so I won’t try just copying the firmware. However it seems to me that perhaps it may be possible to use a similar approach to yours to bring in the https://github.com/aircrack-ng/rtl8812au repository which I think should work with my device.

I do not (yet) know what I am doing, so I am going to take things very slowly and carefully, even though I do not have a stratocaster :slight_smile:

Thanks again,
Paul

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