[PATCH 0/6] wifi: mt76: mt792x: harden USB reset and disconnect paths

[Sean Wang <sean.wang@kernel.org>]

This series hardens mt792x USB reset and disconnect handling.

When the USB control path starts timing out, later register accesses can
keep entering the same dead transport. Each timed-out vendor request may
block for seconds, so reset or disconnect can be delayed by repeated
accesses that can no longer make progress.

Avoid this by failing fast once the USB bus is known to be hung, stopping
reset/init retry paths that cannot recover the device, draining UDMA before
WFSYS reset, and quiescing USB activity before unregistering the device.

This series does the following:
- stop mt7925 init retries once the USB bus is hung
- skip mt7925 reset work once the USB bus is hung
- switch later USB register accesses to no-op bus ops after bus hang
- drain USB UDMA before WFSYS reset
- enable the USB UDMA TX timeout limit
- stop pending USB work and TX paths before unregistering the device

The series is based on wireless-next commit:

21352612198c ("b43: add RF power offset for N-PHY r8 + radio 2057 r8")

It also cherry-picks the following patch from patchwork as a dependency:

wifi: mt76: mt76u: use a threaded NAPI for the RX path
Link: https://lore.kernel.org/all/20260609105301.196302-1-phial@phiality.com/

Sean Wang (6):
  wifi: mt76: mt7925: stop init retries on hung bus
  wifi: mt76: mt7925: skip reset work on hung bus
  wifi: mt76: mt792x: stop USB register access after bus hang
  wifi: mt76: mt792x: drain USB UDMA before WFSYS reset
  wifi: mt76: mt792x: enable USB UDMA TX timeout
  wifi: mt76: mt792x: quiesce USB paths on disconnect

 drivers/net/wireless/mediatek/mt76/mt76.h     |   1 +
 .../net/wireless/mediatek/mt76/mt7925/init.c  |   8 ++
 .../net/wireless/mediatek/mt76/mt7925/mac.c   |   6 +
 .../net/wireless/mediatek/mt76/mt7925/usb.c   |   7 +
 .../net/wireless/mediatek/mt76/mt792x_usb.c   | 124 ++++++++++++++++--
 drivers/net/wireless/mediatek/mt76/usb.c      |  11 ++
 6 files changed, 145 insertions(+), 12 deletions(-)

-- 
2.43.0