Fedora 39 / 40 MT7921K Bluetooth not working

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1

Hey there,

since the recent kernel update bluetooth stopped working. The chipset is a MT7921K.
Kernel Version: 6.8.7-300

I tried manually loading the mtk kernel modules but this does not resolve the problem. rfkill still only reports the wifi part, which is still working.

rfkill
ID TYPE DEVICE      SOFT      HARD
 0 wlan phy0   unblocked unblocked

I tried googeling a strategy to check for module constellations or any idea on how to debug this, but it’s been unsuccessfull so far. Happy to get pointed into the right direction here.

Best,

2

If on fedora 39 that probably should be 6.8.7-200. If on fedora 40 it would be 6.8.7-300.
Which version are you actually using?
Please ensure the title and tags are appropriate for your current release version so we are all looking at the same thing.

The commands lspci and lsusb should identify the proper device chipset and related bus so we are working on the proper devices and drivers.

3

Hey,

I updated to Fedora 40 and thus I landed on 6.8.7-300 but I was facing the same issue on F39 with 6.8.7-200.
I also installed LTS kernel and am facing the same problem.

Here is the lspci output:

00:00.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 14e8
00:00.2 IOMMU: Advanced Micro Devices, Inc. [AMD] Device 14e9
00:01.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 14ea
00:01.2 PCI bridge: Advanced Micro Devices, Inc. [AMD] Device 14ed
00:02.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 14ea
00:02.2 PCI bridge: Advanced Micro Devices, Inc. [AMD] Device 14ee
00:02.4 PCI bridge: Advanced Micro Devices, Inc. [AMD] Device 14ee
00:03.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 14ea
00:04.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 14ea
00:08.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 14ea
00:08.1 PCI bridge: Advanced Micro Devices, Inc. [AMD] Device 14eb
00:08.2 PCI bridge: Advanced Micro Devices, Inc. [AMD] Device 14eb
00:08.3 PCI bridge: Advanced Micro Devices, Inc. [AMD] Device 14eb
00:14.0 SMBus: Advanced Micro Devices, Inc. [AMD] FCH SMBus Controller (rev 71)
00:14.3 ISA bridge: Advanced Micro Devices, Inc. [AMD] FCH LPC Bridge (rev 51)
00:18.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 14f0
00:18.1 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 14f1
00:18.2 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 14f2
00:18.3 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 14f3
00:18.4 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 14f4
00:18.5 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 14f5
00:18.6 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 14f6
00:18.7 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 14f7
01:00.0 Non-Volatile memory controller: Kingston Technology Company, Inc. NV2 NVMe SSD SM2267XT (DRAM-less) (rev 03)
02:00.0 Network controller: MEDIATEK Corp. MT7921K (RZ608) Wi-Fi 6E 80MHz
03:00.0 Non-Volatile memory controller: Samsung Electronics Co Ltd NVMe SSD Controller 980 (DRAM-less)
04:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Phoenix1 (rev c7)
04:00.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Rembrandt Radeon High Definition Audio Controller
04:00.2 Encryption controller: Advanced Micro Devices, Inc. [AMD] Family 19h (Model 74h) CCP/PSP 3.0 Device
04:00.3 USB controller: Advanced Micro Devices, Inc. [AMD] Device 15b9
04:00.4 USB controller: Advanced Micro Devices, Inc. [AMD] Device 15ba
04:00.6 Audio device: Advanced Micro Devices, Inc. [AMD] Family 17h/19h HD Audio Controller
05:00.0 Non-Essential Instrumentation [1300]: Advanced Micro Devices, Inc. [AMD] Device 14ec
06:00.0 Non-Essential Instrumentation [1300]: Advanced Micro Devices, Inc. [AMD] Device 14ec
06:00.3 USB controller: Advanced Micro Devices, Inc. [AMD] Device 15c0
06:00.4 USB controller: Advanced Micro Devices, Inc. [AMD] Device 15c1

and lsusb

lsusb
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 0c45:636c Microdia USB 2.0 Camera
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 002: ID 34d1:0608  USB2.0 HUB
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 005 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 006 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 007 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 008 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
4

that appears to be the wifi controller, but I do not see the bluetooth adapter anywhere.

On mine I see this

(lspci)
05:00.0 Network controller: Intel Corporation Wi-Fi 6E(802.11ax) AX210/AX1675* 2x2 [Typhoon Peak] (rev 1a)


(lsusb)
Bus 001 Device 005: ID 8087:0032 Intel Corp. AX210 Bluetooth

For some reason yours is not even being seen as installed thus not configured.
Please post the output of sudo dmesg | grep Blue

5 
sudo dmesg | grep Blue
<empty>

There is no output.

:roll_eyes:

6

Totally weird it just started working again, with the current and the LTS kernel. Module used is also still just “btusb” . I’m actually very confused what caused this. I stay on top of current updates and I did not see a package I would associate with this behaviour…

7

One thing that is often assumed (and I am guilty of this) is that when situations like this occur the user has already gone through the troubleshooting step of performing a reboot. I did not ask about that and should have.

You also implied that you had done so when you referenced both the current and the LTS kernels.
It is quite possible that a reboot caused the proper drivers to be loaded so things now are working. Checking the dmesg output after a reboot is one way to verify the drivers have or have not loaded properly.

8

Dear Jeff,

now the problem is back and I don’t know why. I performed several reboots after a kernel switch and so on. I’m totally confused I have to say. Any idea what could cause this behaviour?

I can see some ACPI Bios Errors:

20240425_061907
20240425_0619071920×1081 317 KB

But no clue how to determine, if this is connected.

Best,

Matthias

9

Can you boot?

10

Try to power off your PC and disconnect it from mains for 30 seconds. That usually fixes it for me.

11

Hey, yes I can boot and never had a problem. I recall that I had a similiar issues once, because now it is working again. So I think that somehow the firmware of the module gets stuck?
And a reboot fixes it. I’m getting a replacement from the manufacturer. They switched between lots from mediatek to Intel modules. I will try to compare and collect some data on that.

Any idea what I should try to log, especially persist, to catch what I’m looking for?

Best,

Matthias

12

Glad it is working.

Many systems enable networking at boot for Preboot Execution Environment (PXE). BIOS updates and or a power off reboot may be needed to fully reset network hardware.