ath9k: validate rx antenna settings

Many chips are not able to deal with non-consecutive rx antenna selections
and respond with calibration errors, reset errors, etc.
When an antenna is selected as a tx antenna, also flag it for rx to avoid
chip issues.

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/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 01a5f1814bc80f87e6d5bfcb0a8f2199e9ec61d6..cb9a8c9ab4415a1c5c20154af6c8f5a40b4fb770 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -1923,12 +1923,29 @@ static u32 fill_chainmask(u32 cap, u32 new)
        return filled;
 }
 
+static bool validate_antenna_mask(struct ath_hw *ah, u32 val)
+{
+       switch (val & 0x7) {
+       case 0x1:
+       case 0x3:
+       case 0x7:
+               return true;
+       case 0x2:
+               return (ah->caps.rx_chainmask == 1);
+       default:
+               return false;
+       }
+}
+
 static int ath9k_set_antenna(struct ieee80211_hw *hw, u32 tx_ant, u32 rx_ant)
 {
        struct ath_softc *sc = hw->priv;
        struct ath_hw *ah = sc->sc_ah;
 
-       if (!rx_ant || !tx_ant)
+       if (ah->caps.rx_chainmask != 1)
+               rx_ant |= tx_ant;
+
+       if (!validate_antenna_mask(ah, rx_ant) || !tx_ant)
                return -EINVAL;
 
        sc->ant_rx = rx_ant;