btmtk: regression in 6.6.142: NULL pointer dereference in btmtk_usb_hci_wmt_sync during resume from S4

[Sasha Levin]

On Thu, Jul 03, 2026 at 08:34:04AM +0200, Thorsten Leemhuis wrote:
> Hi Chris & Sean! I noticed a report about a regression with btmtk that
> happens in 6.6.y series. This strictly speaking is the domain of the
> stable team, but maybe you want to take a look nevertheless:
>
> https://bugzilla.kernel.org/show_bug.cgi?id=221696

Thanks for the report!

I've queued the missing part of the upstream chain for 6.6.y: 5c5e8c52e3caf
plus its follow-up fixes 67dba2c28fe0af ("Bluetooth: btmtk: Fix failed to send
func ctrl for MediaTek devices."), 099799fa9b76c5 ("Bluetooth: btmtk: Fix
wait_on_bit_timeout interruption during shutdown"), and f0c83a23fcbb42
("Bluetooth: btmtk: Fix btmtk.c undefined reference build error").

-- 
Thanks,
Sasha