[PATCH 4.19 033/220] mt76: fix handling ps-poll frames

[Greg Kroah-Hartman]

From: Felix Fietkau <nbd@xxxxxxxx>

[ Upstream commit 36d910960fae3f9e74bedf3e0ef39ee26bdaa51f ]

Hardware station lookup for pspoll frames can fail, which makes the driver
ignore ps-poll frames. Fix the resulting powersave issues by looking up
the station for pspoll frames in software

Signed-off-by: Felix Fietkau <nbd@xxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/net/wireless/mediatek/mt76/mac80211.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/net/wireless/mediatek/mt76/mac80211.c b/drivers/net/wireless/mediatek/mt76/mac80211.c
index ade4a2029a24a..1b5abd4816ed7 100644
--- a/drivers/net/wireless/mediatek/mt76/mac80211.c
+++ b/drivers/net/wireless/mediatek/mt76/mac80211.c
@@ -548,6 +548,12 @@ mt76_check_ps(struct mt76_dev *dev, struct sk_buff *skb)
 	struct mt76_wcid *wcid = status->wcid;
 	bool ps;
 
+	if (ieee80211_is_pspoll(hdr->frame_control) && !wcid) {
+		sta = ieee80211_find_sta_by_ifaddr(dev->hw, hdr->addr2, NULL);
+		if (sta)
+			wcid = status->wcid = (struct mt76_wcid *) sta->drv_priv;
+	}
+
 	if (!wcid || !wcid->sta)
 		return;
 
-- 
2.20.1