Support for rtl8821CU wifi driver

Help & Support Hardware
1

Hi there,

I’ve got a Mecool M8S Pro+, which has the infamous 9082xs… So I decided to buy a wifi dongle for that device. I checked the topic regarding usb dongles and the RTL8811AU seemed to be a good option: Working USB Wifi/Ethernet adapters for CoreELEC

So I decided to buy this one from AE: https://www.aliexpress.com/item/600Mbps-USB-wireless-wifi-Adapter-2-4GHz-5GHz-WiFi-with-Antenna-Dual-Band-PC-Mini-Computer/32851839784.html?spm=a2g0s.9042311.0.0.51bb4c4dHdMMIS

But the module seems to be a RTL8811CU instead of a RTL8811AU… So when I expected to have it working out-of-the-box, it didn’t happen… I was surprised when discovered that drivers seem to be compatible between them according to Realtek:
https://www.realtek.com/en/component/zoo/category/rtl8811cu-software
For Realtek USB WLAN Family Controller. The driver released on the website only supports the following products: RTL8812AU/RTL8811AU/RTL8192EU/RTL8812BU/RTL8811CU/RTL8814AU: WLAN-only solutions, install WLAN driver

Did a dmesg which gave me:
[ 4475.638832@3] usb 1-1: new high-speed USB device number 8 using xhci-hcd
[ 4475.779121@0] usb 1-1: New USB device found, idVendor=0bda, idProduct=c811
[ 4475.779134@0] usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 4475.779139@0] usb 1-1: Product: 802.11ac NIC
[ 4475.779145@0] usb 1-1: Manufacturer: Realtek
[ 4475.779150@0] usb 1-1: SerialNumber: 123456

I’ve found some “source” code from a Github repository which claims to have obtained the drivers from the CD that comes with the dongle: https://github.com/whitebatman2/rtl8821CU

Can this driver be used with CE?

Thank you very much in advance!

PS: just found another source https://github.com/uzh-rpg/rpg_dwa171_wifidongle
PS2: and another one https://github.com/yklove/rtl8821cu

2

Open a dispute with seller whilst waiting.
You’ll get at least a partial refund.
Sending stuff back to China is a real pain in the arse.
Customs forms etc.
At least the seller won’t sell these adapters with incorrectly advertised chips.

3

Well, I don’t really want a refund for the item. My question is about the possibility of compile those drivers for CE. Can it be done?

4

I successfully compiled this driver for LibreELEC with kernel 5.2 and it works fine. However, it does not compile with kernel 3.14 - I get build errors when trying to build it for CoreELEC amlogic-3.14.

1 Like
5

Looks like this driver has been updated and modified to compile for kernel 5.x, so it makes sense that it’s not compatible with 3.14.

6

Seems like the lowest kernel version that is supported by that driver is 4.4. At least it should be usable with amlogic kernel 4.9.

1 Like
7

I poked around a bit more with the driver and I found a way to make it build with kernel 3.14. It should work with RTL8811CU and RTL8821CU.

2 Likes
8

Good to see that!
We will tell if you know how to correct it.
KI Plus S905D has a Wi-Fi chip SCI s9082c

9

Amazing!!! How can I add this to my CoreElec?

10

CoreELEC-Amlogic.arm-9.0-devel-1560011151-Generic.img.gz
I tested it with this adapter (RTL8811CU) on Le Potato.

2 Likes
11

I also included the SCI s9082c driver in that build. But it is totally untested.

1 Like
12

Many thanks!

I’ve tried in my Mecool M8S Pro+, but I couldn’t make it boot. Black screen…

13

Thanks for uploading the image file. It works on my nexbox s905 soc. Great job!

1 Like
14

It has been in nightly builds for a while now as well.

15

Driver from the nightly builds does not work. Maybe it works in kernel 4.9 N2 builds but not in kernel 3.14 builds.
In my build I used this driver and this hack to make it work with kernel 3.14.

1 Like
16

It works on my nexbox a95x S905 with kernel 3.14.29. I tried lots of ROMs and none of them works except the one you uploaded. Most of them only works with rtl8811au and rtl8821au. The adapter I bought online is rtl8811cu. Hopefully, the stable build will have rtl8811cu soon. Thanks again.

17

I know that the package we added compiles fine for 3.14. Whether it works or not is a different matter, but I don’t see why it shouldn’t work.
You removed that function because it wouldn’t compile or because it crashed on 3.14?

18

It did compile but there was an “Unknown symbol rtl8821c_set_mgnt_xmit_ack” modprobe error during the image creation stage and the wi-fi dongle didn’t work at all. I removed that function, the error was gone and wi-fi dongle is now working.

The driver that is used in CoreELEC nightlies gives even more modprobe “Unknown symbol” errors.

19

Actually, the error was: “depmod: WARNING: 8821cu.ko needs unknown symbol rtl8821c_set_mgnt_xmit_ack”

20

Can you please try this build and see if it works with the card?
https://mega.nz/#!8PpGjQxA!p516Ivq4Q0P4Yxp0ilA8M4ESLBy4HIPVRFn8KBCW2K0