[MT7902] mt7921e driver fails to initialize with "Message 00020001 timeout" on Acer Extensa 15

System Information:

Laptop Model: Acer Extensa 15 EX215-23

WLAN Chipset: MediaTek MT7902 (PCI ID 14c3:7902)

Subsystem ID: AzureWave Device [1a3b:5524]

OS: Arch Linux

Kernel version: 6.19.6-arch1-1

BIOS Version: 1.23 (latest as of 2025/2026)

Description of the Problem:
The MediaTek MT7902 wireless adapter fails to initialize during boot or manual module loading. The driver mt7921e is correctly assigned, but it cannot load the firmware into the device. This issue also causes the integrated Bluetooth module to hang or disappear from the system.

Relevant dmesg logs:

Plaintext

mt7921e 0000:02:00.0: Message 00020001 (seq 1) timeout
mt7921e 0000:02:00.0: HW/SW Version: 0x8a108a10, Build Time: 20220729160652a
mt7921e 0000:02:00.0: WM Firmware Version: ____000000, Build Time: 20220729160729

Attempted workarounds (none helped):

Blacklisting acer_wmi to avoid RFkill conflicts.

Disabling PCI-E ASPM using pcie_aspm=off kernel parameter.

Updating BIOS from v1.19 to v1.23.

Manually providing uncompressed firmware files (.bin) in /usr/lib/firmware/mediatek/.

Expected behavior:
The driver should successfully load the MCU/WM firmware and register the wlan0 interface.

No source file or test is named; start by tracing the mt7921e initialization and firmware-loading path while reproducing the provided dmesg timeout. Done means the MT7902 loads its MCU/WM firmware, registers wlan0, and no longer causes the Bluetooth module to disappear.