carl9170: fix frame drop and WARN due to minstrel_ht change

With "mac80211/minstrel_ht: add support for using CCK rates"
minstrel_ht selects legacy CCK rates as viable rates for
outgoing frames which might be sent as part of an A-MPDU
[IEEE80211_TX_CTL_AMPDU is set].

This behavior triggered the following WARN_ON in the driver:
> WARNING: at carl9170/tx.c:995 carl9170_op_tx+0x1dd/0x6fd
The driver assumed that the rate control algorithm made a
mistake and dropped the frame.

This patch removes the noisy warning altogether and allows
said A-MPDU frames with CCK sample and/or fallback rates to
be transmitted seamlessly.

Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/ath/carl9170/tx.c b/drivers/net/wireless/ath/carl9170/tx.c
index 9c0b150..c61cafa 100644 (file)
--- a/drivers/net/wireless/ath/carl9170/tx.c
+++ b/drivers/net/wireless/ath/carl9170/tx.c
@@ -387,8 +387,7 @@ static void carl9170_tx_status_process_ampdu(struct ar9170 *ar,
        u8 tid;
 
        if (!(txinfo->flags & IEEE80211_TX_CTL_AMPDU) ||
-           txinfo->flags & IEEE80211_TX_CTL_INJECTED ||
-          (!(super->f.mac_control & cpu_to_le16(AR9170_TX_MAC_AGGR))))
+           txinfo->flags & IEEE80211_TX_CTL_INJECTED)
                return;
 
        rcu_read_lock();
@@ -981,30 +980,6 @@ static int carl9170_tx_prepare(struct ar9170 *ar,
 
                SET_VAL(CARL9170_TX_SUPER_AMPDU_FACTOR,
                        txc->s.ampdu_settings, factor);
-
-               for (i = 0; i < CARL9170_TX_MAX_RATES; i++) {
-                       txrate = &info->control.rates[i];
-                       if (txrate->idx >= 0) {
-                               txc->s.ri[i] =
-                                       CARL9170_TX_SUPER_RI_AMPDU;
-
-                               if (WARN_ON(!(txrate->flags &
-                                             IEEE80211_TX_RC_MCS))) {
-                                       /*
-                                        * Not sure if it's even possible
-                                        * to aggregate non-ht rates with
-                                        * this HW.
-                                        */
-                                       goto err_out;
-                               }
-                               continue;
-                       }
-
-                       txrate->idx = 0;
-                       txrate->count = ar->hw->max_rate_tries;
-               }
-
-               mac_tmp |= cpu_to_le16(AR9170_TX_MAC_AGGR);
        }
 
        /*
@@ -1012,11 +987,31 @@ static int carl9170_tx_prepare(struct ar9170 *ar,
         * taken from mac_control. For all fallback rate, the firmware
         * updates the mac_control flags from the rate info field.
         */
-       for (i = 1; i < CARL9170_TX_MAX_RATES; i++) {
+       for (i = 0; i < CARL9170_TX_MAX_RATES; i++) {
+               __le32 phy_set;
                txrate = &info->control.rates[i];
                if (txrate->idx < 0)
                        break;
 
+               phy_set = carl9170_tx_physet(ar, info, txrate);
+               if (i == 0) {
+                       /* first rate - part of the hw's frame header */
+                       txc->f.phy_control = phy_set;
+
+                       if (ampdu && txrate->flags & IEEE80211_TX_RC_MCS)
+                               mac_tmp |= cpu_to_le16(AR9170_TX_MAC_AGGR);
+                       if (carl9170_tx_rts_check(ar, txrate, ampdu, no_ack))
+                               mac_tmp |= cpu_to_le16(AR9170_TX_MAC_PROT_RTS);
+                       else if (carl9170_tx_cts_check(ar, txrate))
+                               mac_tmp |= cpu_to_le16(AR9170_TX_MAC_PROT_CTS);
+
+               } else {
+                       /* fallback rates are stored in the firmware's
+                        * retry rate set array.
+                        */
+                       txc->s.rr[i - 1] = phy_set;
+               }
+
                SET_VAL(CARL9170_TX_SUPER_RI_TRIES, txc->s.ri[i],
                        txrate->count);
 
@@ -1027,21 +1022,13 @@ static int carl9170_tx_prepare(struct ar9170 *ar,
                        txc->s.ri[i] |= (AR9170_TX_MAC_PROT_CTS <<
                                CARL9170_TX_SUPER_RI_ERP_PROT_S);
 
-               txc->s.rr[i - 1] = carl9170_tx_physet(ar, info, txrate);
+               if (ampdu && (txrate->flags & IEEE80211_TX_RC_MCS))
+                       txc->s.ri[i] |= CARL9170_TX_SUPER_RI_AMPDU;
        }
 
-       txrate = &info->control.rates[0];
-       SET_VAL(CARL9170_TX_SUPER_RI_TRIES, txc->s.ri[0], txrate->count);
-
-       if (carl9170_tx_rts_check(ar, txrate, ampdu, no_ack))
-               mac_tmp |= cpu_to_le16(AR9170_TX_MAC_PROT_RTS);
-       else if (carl9170_tx_cts_check(ar, txrate))
-               mac_tmp |= cpu_to_le16(AR9170_TX_MAC_PROT_CTS);
-
        txc->s.len = cpu_to_le16(skb->len);
        txc->f.length = cpu_to_le16(len + FCS_LEN);
        txc->f.mac_control = mac_tmp;
-       txc->f.phy_control = carl9170_tx_physet(ar, info, txrate);
 
        arinfo = (void *)info->rate_driver_data;
        arinfo->timeout = jiffies;
@@ -1381,9 +1368,9 @@ static void carl9170_tx(struct ar9170 *ar)
 }
 
 static bool carl9170_tx_ampdu_queue(struct ar9170 *ar,
-       struct ieee80211_sta *sta, struct sk_buff *skb)
+       struct ieee80211_sta *sta, struct sk_buff *skb,
+       struct ieee80211_tx_info *txinfo)
 {
-       struct _carl9170_tx_superframe *super = (void *) skb->data;
        struct carl9170_sta_info *sta_info;
        struct carl9170_sta_tid *agg;
        struct sk_buff *iter;
@@ -1450,7 +1437,7 @@ err_unlock:
 
 err_unlock_rcu:
        rcu_read_unlock();
-       super->f.mac_control &= ~cpu_to_le16(AR9170_TX_MAC_AGGR);
+       txinfo->flags &= ~IEEE80211_TX_CTL_AMPDU;
        carl9170_tx_status(ar, skb, false);
        ar->tx_dropped++;
        return false;
@@ -1492,7 +1479,7 @@ void carl9170_op_tx(struct ieee80211_hw *hw,
                 * sta == NULL checks are redundant in this
                 * special case.
                 */
-               run = carl9170_tx_ampdu_queue(ar, sta, skb);
+               run = carl9170_tx_ampdu_queue(ar, sta, skb, info);
                if (run)
                        carl9170_tx_ampdu(ar);