ath9k: implement .get_antenna and .set_antenna

On MIMO chips this can be used to enable/disable hardware chains, ensuring
that the MCS information is updated accordingly.
On non-MIMO chips with rx diversity (e.g. 9285), this configures the rx
input antenna.

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

1 files changed, 71 insertions, 0 deletions

diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 19c78be3dc41..c8ac2ce61ffe 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -281,6 +281,22 @@ static bool ath_complete_reset(struct ath_softc *sc, bool start)
 			ath_start_ani(common);
 	}
 
+	if (ath9k_hw_ops(ah)->antdiv_comb_conf_get && sc->ant_rx != 3) {
+		struct ath_hw_antcomb_conf div_ant_conf;
+		u8 lna_conf;
+
+		ath9k_hw_antdiv_comb_conf_get(ah, &div_ant_conf);
+
+		if (sc->ant_rx == 1)
+			lna_conf = ATH_ANT_DIV_COMB_LNA1;
+		else
+			lna_conf = ATH_ANT_DIV_COMB_LNA2;
+		div_ant_conf.main_lna_conf = lna_conf;
+		div_ant_conf.alt_lna_conf = lna_conf;
+
+		ath9k_hw_antdiv_comb_conf_set(ah, &div_ant_conf);
+	}
+
 	ieee80211_wake_queues(sc->hw);
 
 	return true;
@@ -2379,6 +2395,59 @@ static int ath9k_get_stats(struct ieee80211_hw *hw,
 	return 0;
 }
 
+static u32 fill_chainmask(u32 cap, u32 new)
+{
+	u32 filled = 0;
+	int i;
+
+	for (i = 0; cap && new; i++, cap >>= 1) {
+		if (!(cap & BIT(0)))
+			continue;
+
+		if (new & BIT(0))
+			filled |= BIT(i);
+
+		new >>= 1;
+	}
+
+	return filled;
+}
+
+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)
+		return -EINVAL;
+
+	sc->ant_rx = rx_ant;
+	sc->ant_tx = tx_ant;
+
+	if (ah->caps.rx_chainmask == 1)
+		return 0;
+
+	/* AR9100 runs into calibration issues if not all rx chains are enabled */
+	if (AR_SREV_9100(ah))
+		ah->rxchainmask = 0x7;
+	else
+		ah->rxchainmask = fill_chainmask(ah->caps.rx_chainmask, rx_ant);
+
+	ah->txchainmask = fill_chainmask(ah->caps.tx_chainmask, tx_ant);
+	ath9k_reload_chainmask_settings(sc);
+
+	return 0;
+}
+
+static int ath9k_get_antenna(struct ieee80211_hw *hw, u32 *tx_ant, u32 *rx_ant)
+{
+	struct ath_softc *sc = hw->priv;
+
+	*tx_ant = sc->ant_tx;
+	*rx_ant = sc->ant_rx;
+	return 0;
+}
+
 struct ieee80211_ops ath9k_ops = {
 	.tx 		    = ath9k_tx,
 	.start 		    = ath9k_start,
@@ -2405,4 +2474,6 @@ struct ieee80211_ops ath9k_ops = {
 	.tx_frames_pending  = ath9k_tx_frames_pending,
 	.tx_last_beacon     = ath9k_tx_last_beacon,
 	.get_stats	    = ath9k_get_stats,
+	.set_antenna	    = ath9k_set_antenna,
+	.get_antenna	    = ath9k_get_antenna,
 };