How to install wifi kernel driver on CachyOS?

Issues & Assistance
1

I have a system with an RTL8191SU wifi adapter. According to this website, it should be supported by Linux’s r8712u kernel module.

What’s the correct way to install it on CachyOS? It does not seem to be part of the standard installation.

2

if linux-firmware-realtek is installed, then it normaly should work.

3

I verified that linux-firmware-realtek is installed. What is missing though is the appropriate kernel module which probably needs to be installed separately. What’s the regular way to accomplish this on CachyOS?

4

Normaly it should be in the kernel (unless someone forgot to tick that box when building the kernel). There is a github page for a DKMS, but they wrote that there is no need to use it anymore and the last supported kernel 6.15.

You would need to install the LTS (6.12) or Hardened (6.15) kernel to use it. To install it you have the following options:

  • build from git, build instructions are on the git page
  • build from AUR with paru or yay
paru -Syu 8192cu-dkms

sudo pacman -Syu rtl8821cu-morrownr-dkms-git

If you want to use the actual kernel, then maybe the RTW88 DKMS might work

It’s also in the AUR as rtw88-dkms-git (but sadly not in the ChaoticAUR)
Or you rebuild the kernel with CachyOS Kernelmanager and make sure the box is ticked (this will take some time).

5

Thanks for the hints. When I switch to the LTS (6.12.) kernel, the r8712u module is used which is shipped with CachyOS and loaded automatically.
cf. Realtek 802.11n, 802.11ac and 802.11ax drivers — Linux Wireless documentation

I tried to install the rtl8192su (both via AUR using yay [AUR (en) - rtl8192su-git] as well as manually getting it from the repository and trying to compile it). However, both for the 6.12 (LTS) and the 6.16 (stable) kernel it failed to compile with some errors in the C code (maybe it only compiles for later kernels; I’ll need to look into it more closely)

I’m wondering why you suggest the rtl8821cu or the rtw88 modules should wirk with the wifi?(which is a 13D3:3306 IMC Networks Mediao 802.11n WLAN [Realtek RTL8191SU])
I tried rtl8821cu-morrownr-dkms-git and it did not work. Should it?

6

rtw88 is a DKMS of the kernel module, that should work with every kernel

7

Unfortunately, as of today the linux-cachyos-lts (6.12.62-2) isn’t compiled anymore with r8712u module.