[PATCH v2 1/8] Bluetooth: btmtk: Add MT6639 (MT7927) Bluetooth support

[Javier Tia]

Hi Sean,

Thank you for the review. Both items are addressed in v3.

On Wed, Mar 26, 2026 Sean Wang wrote:
> Using raw CHIPID=0x0000 to unconditionally force 0x6639 seems fragile.
> If another device later hits the same missing-ID condition, it would
> also be misdetected as MT6639. Normally this kind of quirk could be
> carried in .driver_data, but since btusb.c is shared, I'm not sure
> that is the right fit here either. This should probably be handled
> through a more device-specific fallback instead of mapping all zero
> CHIPID cases to 0x6639.

Agreed. In v3, the zero-CHIPID fallback is scoped to a static
VID/PID table of known MT6639 USB devices. Only those specific
devices get forced to 0x6639 - any other device reading zero will
fall through to the default "unsupported hardware" path. This
follows the WiFi-side pattern where is_mt7927_hw is derived from
the PCI device table, not the chip register.

> I would prefer using the mediatek/mt7927/ folder naming here. mt7927
> is more widely recognized, and using it would avoid unnecessary
> confusion.

Done. The firmware path is now mediatek/mt7927/ in both the
FIRMWARE_MT7927 define and btmtk_fw_get_filename(). This matches
the WiFi firmware convention (mediatek/mt7927/WIFI_RAM_CODE_...).
The linux-firmware MR !946 has also been updated to use the
mt7927 directory.

v3 sent with these changes:
https://lore.kernel.org/linux-bluetooth/20260326-mt7927-bt-support-v3-0-fa7ebd424323@jetm.me/T/#t

Best,
Javier