ath9k: fix a DMA related race condition on reset
When ath_drain_all_txq fails to stop DMA, it issues a hw reset. This reset
happens at a very problematic point in time, when the hardware rx path has
not been stopped yet. This could lead to memory corruption, hardware hangs
or other issues.
To fix these issues, simply remove the reset entirely and check the tx DMA
stop status to prevent problems with fast channel changes.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index 0d0bec3..0963071 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -329,7 +329,7 @@
struct ath_txq *ath_txq_setup(struct ath_softc *sc, int qtype, int subtype);
void ath_tx_cleanupq(struct ath_softc *sc, struct ath_txq *txq);
int ath_tx_setup(struct ath_softc *sc, int haltype);
-void ath_drain_all_txq(struct ath_softc *sc, bool retry_tx);
+bool ath_drain_all_txq(struct ath_softc *sc, bool retry_tx);
void ath_draintxq(struct ath_softc *sc,
struct ath_txq *txq, bool retry_tx);
void ath_tx_node_init(struct ath_softc *sc, struct ath_node *an);