ath9k_hw: fix potential spurious tx error bit interpretation

According to documentation, AR_ExcessiveRetries, AR_Filtered and
AR_FIFOUnderrun are only valid if AR_FrmXmitOK is clear.

Not checking this might result in suboptimal FIFO settings, unnecessary
retransmissions, or other connectivity issues.

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

1 files changed, 9 insertions, 7 deletions

diff --git a/drivers/net/wireless/ath/ath9k/ar9002_mac.c b/drivers/net/wireless/ath/ath9k/ar9002_mac.c
index 3b4c52c9181c..f0268e5eab34 100644
--- a/drivers/net/wireless/ath/ath9k/ar9002_mac.c
+++ b/drivers/net/wireless/ath/ath9k/ar9002_mac.c
@@ -237,13 +237,15 @@ static int ar9002_hw_proc_txdesc(struct ath_hw *ah, void *ds,
         status = ACCESS_ONCE(ads->ds_txstatus1);
         if (status & AR_FrmXmitOK)
                 ts->ts_status |= ATH9K_TX_ACKED;
-        if (status & AR_ExcessiveRetries)
-                ts->ts_status |= ATH9K_TXERR_XRETRY;
-        if (status & AR_Filtered)
-                ts->ts_status |= ATH9K_TXERR_FILT;
-        if (status & AR_FIFOUnderrun) {
-                ts->ts_status |= ATH9K_TXERR_FIFO;
-                ath9k_hw_updatetxtriglevel(ah, true);
+        else {
+                if (status & AR_ExcessiveRetries)
+                        ts->ts_status |= ATH9K_TXERR_XRETRY;
+                if (status & AR_Filtered)
+                        ts->ts_status |= ATH9K_TXERR_FILT;
+                if (status & AR_FIFOUnderrun) {
+                        ts->ts_status |= ATH9K_TXERR_FIFO;
+                        ath9k_hw_updatetxtriglevel(ah, true);
+                }
         }
         if (status & AR_TxTimerExpired)
                 ts->ts_status |= ATH9K_TXERR_TIMER_EXPIRED;