band_idx starts out as 0xff, which tells the firmware to pick the band on its own. A remain-on-channel grant normally writes a real index over it before anything else looks. Two cases never see that: an MLD station throws the grant away, and an AP has no association to trigger one. The TX descriptor reads the same field into a two-bit slot, so the marker comes out as 3. Every data frame from those two goes out tagged band 3. Beacons are fine, they reach the firmware separately and never build a descriptor. Same numbers on an MT7925 and on a Netgear A9000: stock patched station, one link 0x00000001 0x00000001 station, two links 0x00003001 0x00000001 AP 0x00003013 0x00000013 real band index, STA 0x00001001 0x00001001 real band index, AP 0x00001013 0x00001013 Only the marker cases move. Fixes: 0cb349d742d1 ("wifi: mt76: mt7925: update mt7925_mac_link_bss_add for MLO") Signed-off-by: Devin Wittmayer --- drivers/net/wireless/mediatek/mt76/mt7925/mac.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/mediatek/mt76/mt7925/mac.c b/drivers/net/wireless/mediatek/mt76/mt7925/mac.c index 101f571b0..3b82c9de2 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7925/mac.c +++ b/drivers/net/wireless/mediatek/mt76/mt7925/mac.c @@ -798,7 +798,8 @@ mt7925_mac_write_txwi(struct mt76_dev *dev, __le32 *txwi, val = FIELD_PREP(MT_TXD1_WLAN_IDX, wcid->idx) | FIELD_PREP(MT_TXD1_OWN_MAC, omac_idx); - if (band_idx) + /* 0xff means BAND_AUTO to the firmware, and TGID cannot encode it */ + if (band_idx && band_idx != 0xff) val |= FIELD_PREP(MT_TXD1_TGID, band_idx); txwi[1] = cpu_to_le32(val);