ath9k: disable unnecessary PHY error reporting

PHY errors relevant for ANI are always tracked by hardware counters, the
bits that allow them to pass through the rx filter are independent of that.
Enabling PHY errors in the rx filter often creates lots of useless DMA traffic
and might be responsible for some of the rx dma stop failure warnings.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Cc: stable@kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath9k/ani.c

@@ -504,9 +504,6 @@ static void ath9k_ani_reset_old(struct ath_hw *ah, bool is_scanning)
 		ath9k_hw_ani_control(ah, ATH9K_ANI_CCK_WEAK_SIGNAL_THR,
 				     ATH9K_ANI_CCK_WEAK_SIG_THR);
 
-		ath9k_hw_setrxfilter(ah, ath9k_hw_getrxfilter(ah) |
-				     ATH9K_RX_FILTER_PHYERR);
-
 		ath9k_ani_restart(ah);
 		return;
 	}
@@ -527,8 +524,6 @@ static void ath9k_ani_reset_old(struct ath_hw *ah, bool is_scanning)
 		ath9k_hw_ani_control(ah, ATH9K_ANI_FIRSTEP_LEVEL,
 				     aniState->firstepLevel);
 
-	ath9k_hw_setrxfilter(ah, ath9k_hw_getrxfilter(ah) &
-			     ~ATH9K_RX_FILTER_PHYERR);
 	ath9k_ani_restart(ah);
 
 	ENABLE_REGWRITE_BUFFER(ah);

drivers/net/wireless/ath/ath9k/recv.c

@@ -433,12 +433,9 @@ void ath_rx_cleanup(struct ath_softc *sc)
 
 u32 ath_calcrxfilter(struct ath_softc *sc)
 {
-#define	RX_FILTER_PRESERVE (ATH9K_RX_FILTER_PHYERR | ATH9K_RX_FILTER_PHYRADAR)
-
 	u32 rfilt;
 
-	rfilt = (ath9k_hw_getrxfilter(sc->sc_ah) & RX_FILTER_PRESERVE)
-		| ATH9K_RX_FILTER_UCAST | ATH9K_RX_FILTER_BCAST
+	rfilt = ATH9K_RX_FILTER_UCAST | ATH9K_RX_FILTER_BCAST
 		| ATH9K_RX_FILTER_MCAST;
 
 	if (sc->rx.rxfilter & FIF_PROBE_REQ)