Devin WittmayerandFelix Fietkau 2d9b52d224 wifi: mt76: restrict NPU/PPE active checks to MMIO devices
mt76_npu_device_active() and mt76_ppe_device_active() read dev->mmio.npu
and dev->mmio.ppe_dev. The mmio, usb and sdio bus structs share a union in
struct mt76_dev, so on USB and SDIO these read unrelated data from the
usb/sdio struct, which is non-NULL in practice.

mt76_npu_device_active() then returns true on USB, and
mt76_rx_poll_complete() takes the offload path and skips
mt76_rx_aggr_reorder(). RX A-MPDU subframes are delivered out of order and
the peer's TCP stack treats that as loss: heavy retransmissions and reduced
throughput in AP mode. Seen on mt7921u, mt7925u, mt76x2u and mt76x0u.

Gate both helpers on mt76_is_mmio() so they only run for the bus type that
owns the mmio union member.

Fixes: 7fb554b1b623 ("wifi: mt76: Introduce the NPU generic layer")
Cc: [email protected]
Tested-by: Nick Morrow <[email protected]>
Signed-off-by: Devin Wittmayer <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Felix Fietkau <[email protected]>
2026-07-21 15:34:22 +02:00
2021-04-14 09:12:11 +02:00
2025-10-13 11:11:19 +02:00
2026-05-04 08:37:03 +00:00
2026-07-21 12:09:57 +02:00
2026-07-21 12:09:57 +02:00
S
Description
mac80211 driver for MediaTek MT76x0e, MT76x2e, MT7603, MT7615, MT7628 and MT7688
BSD-3-Clause
105 MiB
Languages
C 99.7%
Perl 0.2%
Makefile 0.1%