ath9k: Handle different TX and RX streams properly.

This patch fixes an issue when the TX and RX streams are different.

Signed-off-by: Senthil Balasubramanian <senthilkumar@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 14 insertions, 12 deletions

diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 52dfa43bc529..961b0ce6ef3e 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -889,6 +889,7 @@ static void setup_ht_cap(struct ath_softc *sc,
 {
 #define ATH9K_HT_CAP_MAXRXAMPDU_65536 0x3       /* 2 ^ 16 */
 #define ATH9K_HT_CAP_MPDUDENSITY_8 0x6          /* 8 usec */
+        u8 tx_streams, rx_streams;
 
         ht_info->ht_supported = true;
         ht_info->cap = IEEE80211_HT_CAP_SUP_WIDTH_20_40 |
@@ -901,21 +902,22 @@ static void setup_ht_cap(struct ath_softc *sc,
 
         /* set up supported mcs set */
         memset(&ht_info->mcs, 0, sizeof(ht_info->mcs));
+        tx_streams = !(sc->tx_chainmask & (sc->tx_chainmask - 1)) ? 1 : 2;
+        rx_streams = !(sc->rx_chainmask & (sc->rx_chainmask - 1)) ? 1 : 2;
 
-        switch(sc->rx_chainmask) {
-        case 1:
-                ht_info->mcs.rx_mask[0] = 0xff;
-                break;
-        case 3:
-        case 5:
-        case 7:
-        default:
-                ht_info->mcs.rx_mask[0] = 0xff;
-                ht_info->mcs.rx_mask[1] = 0xff;
-                break;
+        if (tx_streams != rx_streams) {
+                DPRINTF(sc, ATH_DBG_CONFIG, "TX streams %d, RX streams: %d\n",
+                        tx_streams, rx_streams);
+                ht_info->mcs.tx_params |= IEEE80211_HT_MCS_TX_RX_DIFF;
+                ht_info->mcs.tx_params |= ((tx_streams - 1) <<
+                                IEEE80211_HT_MCS_TX_MAX_STREAMS_SHIFT);
         }
 
-        ht_info->mcs.tx_params = IEEE80211_HT_MCS_TX_DEFINED;
+        ht_info->mcs.rx_mask[0] = 0xff;
+        if (rx_streams >= 2)
+                ht_info->mcs.rx_mask[1] = 0xff;
+
+        ht_info->mcs.tx_params |= IEEE80211_HT_MCS_TX_DEFINED;
 }
 
 static void ath9k_bss_assoc_info(struct ath_softc *sc,