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RTL8812AU driver listed in lsmod, but not working

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Majouououuo

I have a TP-Link Archer T2U Plus USB WiFi adapter that has the Realtek RTL8821AU chipset. The driver isn't preinstalled on Ubuntu 20.04.3 (kernel 5.11.0-27-generic, if it is preinstalled on 21.10 or 20.04.4, please let me know and I will upgrade) so I had to manually install the driver. I found one in the universe (https://packages.ubuntu.com/focal/rtl8812au-dkms) that's made for the RTL8812AU, but it also works for RTL8821AU, because there is RTL8821AU written in the /os_dep/linux/usb_intf.c file.

I installed it with sudo apt install rtl8812au-dkms, however, the driver doesn't work, because TP-Link Archer T2U Plus's ID isn't listed in the /os_dep/linux/usb_intf.c file. So I downloaded the source code of the driver (using apt download rtl8812au-dkms), unzipped the .deb file, got the ID from the lsusb command (it's 2357:0120) and added a line

{USB_DEVICE(0x2357, 0x0120), .driver_info = RTL8821}, /* TP Link - T2U Plus */

under #ifdef CONFIG_RTL8821A in the usb_intf.c file.

Then I compiled the source code with make and sudo make install and restarted my PC and the driver doesn't work. It is loaded, because it's showing in lsmod everytime I plug my WiFi adapter, but in lsmod it's saying used by: 0.

I am sure the driver works with the RTL8821AU chipset and I am sure Archer T2U Plus is using this chipset, but it doesn't seem to work. I think the problem is that I installed it wrong, or that the 8812au module showing up in lsmod is another module (that I had tried before trying this package from the universe, because I had tried a lot of different drivers before trying this one) and the old module is handling the WiFi adapter instead of the rtl8812au-dkms package from the universe (compiled from source code with the edited usb_intf.c file).

I tried to run sudo depmod -a and sudo modprobe 8812au before restarting my PC, I also tried to install it while the adapter was unplugged and plugging it after a reboot, I tried using USB 3.0 ports on my case, USB 2.0 and 3.0 on my motherboard, nothing worked.

Can you please guide me step-by-step on how to compile and install the driver after I edited the source code or how to see if the module really is the one with the edited usb_intf.c file (I am new to Linux)?

BTW the driver has dkms, but because I installed it using sudo make install it isn't showing up in the dkms status. Also, after installing the driver the WiFi adapter isn't showing up in nmcli device or lshw -C network, only in lsusb and the module in lsmod.

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heynnema avatar
ru flag
heynnema
Uninstall the driver that you moded, and try https://github.com/morrownr/8821au or https://github.com/morrownr/8821au-20210708
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chili555 avatar
cn flag
chili555
It doesn't lock partitions. Here is an explanation: https://wireless.wiki.kernel.org/en/users/drivers/iwlwifi#about_dual-boot_with_windows_and_fast-boot_enabled What does this tell us? sudo modprobe 8812au && sudo dmesg | grep 8812 Please edit your question to show the results. I have deleted my usually accurate but not today answer.
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