[Bug 221551] New: btmtk: MT7921 (USB ID 0e8d:e020) Bluetooth broken since 7.0.7 — fix commit for 0489:e0e2 does not cover this PID

[bugzilla-daemon@kernel.org]

https://bugzilla.kernel.org/show_bug.cgi?id=221551

            Bug ID: 221551
           Summary: btmtk: MT7921 (USB ID 0e8d:e020) Bluetooth broken
                    since 7.0.7 — fix commit for 0489:e0e2 does not cover
                    this PID
           Product: Drivers
           Version: 2.5
          Hardware: All
                OS: Linux
            Status: NEW
          Severity: blocking
          Priority: P3
         Component: Bluetooth
          Assignee: linux-bluetooth@vger.kernel.org
          Reporter: gagnieux.virgil@proton.me
        Regression: No

Created attachment 310158
  --> https://bugzilla.kernel.org/attachment.cgi?id=310158&action=edit
dmesg (from kernel 7.0.9, relevant lines)

Regression: Bluetooth controller stops initialising on a MediaTek MT7921
since kernel 7.0.7. Last known good: 7.0.6.

Same symptom as the regression already discussed and patched for USB ID
0489:e0e2, but the fix does NOT resolve it for my device (0e8d:e020),
which suggests the patch missed a code path / device ID.

Hardware
--------
lspci:  03:00.0 Network controller [0280]: MEDIATEK Corp. Device [14c3:7920]
        Kernel driver in use: mt7921e
lsusb:  Bus 003 Device 006: ID 0e8d:e020 MediaTek Inc. Wireless_Device

Kernels tested
--------------
7.0.6              : Bluetooth works
7.0.8 / 7.0.9      : broken (mainline Arch build, please confirm if you also
tested it)
7.0.9-hardened1-1  : broken (linux-hardened, includes the backport
                   
https://github.com/anthraxx/linux-hardened/commit/<…81d80fcd09>
                    which targets 0489:e0e2 — it does NOT fix 0e8d:e020)

dmesg (relevant lines)
----------------------
[   24.800153] Bluetooth: hci0: HW/SW Version: 0x008a008a, Build Time:
20260224111231
[   24.922472] Bluetooth: hci0: Failed to send wmt func ctrl (-22)
[   24.922477] Bluetooth: hci0: HCI Enhanced Setup Synchronous Connection
               command is advertised, but not supported.

Userspace state
---------------
bluetoothctl list  → (no output)
bluetoothctl show  → No default controller available
rfkill             → hci0 not present / soft blocked depending on boot

Versions
--------
bluez                     : <colle ta version>
linux-firmware            : <…>
linux-firmware-mediatek   : <…>

Steps to reproduce
------------------
1. Boot kernel >= 7.0.7 on a system with MediaTek 14c3:7920 / USB 0e8d:e020
2. Bluetooth controller fails to initialise; -EINVAL on wmt func ctrl

Expected
--------
Controller comes up, same as on 7.0.6.

Related
-------
- Arch forum thread: https://bbs.archlinux.org/viewtopic.php?id=313552
- Related thread (same symptom, different PID 0489:e0d8):
  https://bbs.archlinux.org/viewtopic.php?id=313561
- Fix that addresses 0489:e0e2 only:
  https://github.com/anthraxx/linux-hardened/commit/<…81d80fcd09>

Please note: the existing fix above is referenced because it explicitly
does NOT cover USB ID 0e8d:e020. A second code path / device-ID entry
seems to be needed.

I can test patches.

-- 
You may reply to this email to add a comment.

You are receiving this mail because:
You are the assignee for the bug.