carl9170: refactor carl9170_update_beacon

This patch moves parts of carl9170_update_beacon
into separate subroutines, so the parts become
more manageable.

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 ef4ec0da6e498288cafe11ff6770b6eaf96d13e8..9c0b150d5b8e2a20b3373d91b733362f083df63a 100644 (file)
--- a/drivers/net/wireless/ath/carl9170/tx.c
+++ b/drivers/net/wireless/ath/carl9170/tx.c
@@ -1520,35 +1520,92 @@ void carl9170_tx_scheduler(struct ar9170 *ar)
                carl9170_tx(ar);
 }
 
-int carl9170_update_beacon(struct ar9170 *ar, const bool submit)
+/* caller has to take rcu_read_lock */
+static struct carl9170_vif_info *carl9170_pick_beaconing_vif(struct ar9170 *ar)
 {
-       struct sk_buff *skb = NULL;
        struct carl9170_vif_info *cvif;
+       int i = 1;
+
+       /* The AR9170 hardware has no fancy beacon queue or some
+        * other scheduling mechanism. So, the driver has to make
+        * due by setting the two beacon timers (pretbtt and tbtt)
+        * once and then swapping the beacon address in the HW's
+        * register file each time the pretbtt fires.
+        */
+
+       cvif = rcu_dereference(ar->beacon_iter);
+       if (ar->vifs > 0 && cvif) {
+               do {
+                       list_for_each_entry_continue_rcu(cvif, &ar->vif_list,
+                                                        list) {
+                               if (cvif->active && cvif->enable_beacon)
+                                       goto out;
+                       }
+               } while (ar->beacon_enabled && i--);
+       }
+
+out:
+       rcu_assign_pointer(ar->beacon_iter, cvif);
+       return cvif;
+}
+
+static bool carl9170_tx_beacon_physet(struct ar9170 *ar, struct sk_buff *skb,
+                                     u32 *ht1, u32 *plcp)
+{
        struct ieee80211_tx_info *txinfo;
        struct ieee80211_tx_rate *rate;
-       __le32 *data, *old = NULL;
-       unsigned int plcp, power, chains;
-       u32 word, ht1, off, addr, len;
-       int i = 0, err = 0;
+       unsigned int power, chains;
+       bool ht_rate;
 
-       rcu_read_lock();
-       cvif = rcu_dereference(ar->beacon_iter);
-retry:
-       if (ar->vifs == 0 || !cvif)
-               goto out_unlock;
+       txinfo = IEEE80211_SKB_CB(skb);
+       rate = &txinfo->control.rates[0];
+       ht_rate = !!(txinfo->control.rates[0].flags & IEEE80211_TX_RC_MCS);
+       carl9170_tx_rate_tpc_chains(ar, txinfo, rate, plcp, &power, &chains);
 
-       list_for_each_entry_continue_rcu(cvif, &ar->vif_list, list) {
-               if (cvif->active && cvif->enable_beacon)
-                       goto found;
+       *ht1 = AR9170_MAC_BCN_HT1_TX_ANT0;
+       if (chains == AR9170_TX_PHY_TXCHAIN_2)
+               *ht1 |= AR9170_MAC_BCN_HT1_TX_ANT1;
+       SET_VAL(AR9170_MAC_BCN_HT1_PWR_CTRL, *ht1, 7);
+       SET_VAL(AR9170_MAC_BCN_HT1_TPC, *ht1, power);
+       SET_VAL(AR9170_MAC_BCN_HT1_CHAIN_MASK, *ht1, chains);
+
+       if (ht_rate) {
+               *ht1 |= AR9170_MAC_BCN_HT1_HT_EN;
+               if (rate->flags & IEEE80211_TX_RC_SHORT_GI)
+                       *plcp |= AR9170_MAC_BCN_HT2_SGI;
+
+               if (rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) {
+                       *ht1 |= AR9170_MAC_BCN_HT1_BWC_40M_SHARED;
+                       *plcp |= AR9170_MAC_BCN_HT2_BW40;
+               } else if (rate->flags & IEEE80211_TX_RC_DUP_DATA) {
+                       *ht1 |= AR9170_MAC_BCN_HT1_BWC_40M_DUP;
+                       *plcp |= AR9170_MAC_BCN_HT2_BW40;
+               }
+
+               SET_VAL(AR9170_MAC_BCN_HT2_LEN, *plcp, skb->len + FCS_LEN);
+       } else {
+               if (*plcp <= AR9170_TX_PHY_RATE_CCK_11M)
+                       *plcp |= ((skb->len + FCS_LEN) << (3 + 16)) + 0x0400;
+               else
+                       *plcp |= ((skb->len + FCS_LEN) << 16) + 0x0010;
        }
 
-       if (!ar->beacon_enabled || i++)
-               goto out_unlock;
+       return ht_rate;
+}
 
-       goto retry;
+int carl9170_update_beacon(struct ar9170 *ar, const bool submit)
+{
+       struct sk_buff *skb = NULL;
+       struct carl9170_vif_info *cvif;
+       __le32 *data, *old = NULL;
+       u32 word, ht1, plcp, off, addr, len;
+       int i = 0, err = 0;
+       bool ht_rate;
 
-found:
-       rcu_assign_pointer(ar->beacon_iter, cvif);
+       rcu_read_lock();
+       cvif = carl9170_pick_beaconing_vif(ar);
+       if (!cvif)
+               goto out_unlock;
 
        skb = ieee80211_beacon_get_tim(ar->hw, carl9170_get_vif(cvif),
                NULL, NULL);
@@ -1558,7 +1615,6 @@ found:
                goto err_free;
        }
 
-       txinfo = IEEE80211_SKB_CB(skb);
        spin_lock_bh(&ar->beacon_lock);
        data = (__le32 *)skb->data;
        if (cvif->beacon)
@@ -1588,43 +1644,14 @@ found:
                goto err_unlock;
        }
 
-       ht1 = AR9170_MAC_BCN_HT1_TX_ANT0;
-       rate = &txinfo->control.rates[0];
-       carl9170_tx_rate_tpc_chains(ar, txinfo, rate, &plcp, &power, &chains);
-       if (!(txinfo->control.rates[0].flags & IEEE80211_TX_RC_MCS)) {
-               if (plcp <= AR9170_TX_PHY_RATE_CCK_11M)
-                       plcp |= ((skb->len + FCS_LEN) << (3 + 16)) + 0x0400;
-               else
-                       plcp |= ((skb->len + FCS_LEN) << 16) + 0x0010;
-       } else {
-               ht1 |= AR9170_MAC_BCN_HT1_HT_EN;
-               if (rate->flags & IEEE80211_TX_RC_SHORT_GI)
-                       plcp |= AR9170_MAC_BCN_HT2_SGI;
-
-               if (rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) {
-                       ht1 |= AR9170_MAC_BCN_HT1_BWC_40M_SHARED;
-                       plcp |= AR9170_MAC_BCN_HT2_BW40;
-               }
-               if (rate->flags & IEEE80211_TX_RC_DUP_DATA) {
-                       ht1 |= AR9170_MAC_BCN_HT1_BWC_40M_DUP;
-                       plcp |= AR9170_MAC_BCN_HT2_BW40;
-               }
-
-               SET_VAL(AR9170_MAC_BCN_HT2_LEN, plcp, skb->len + FCS_LEN);
-       }
-
-       SET_VAL(AR9170_MAC_BCN_HT1_PWR_CTRL, ht1, 7);
-       SET_VAL(AR9170_MAC_BCN_HT1_TPC, ht1, power);
-       SET_VAL(AR9170_MAC_BCN_HT1_CHAIN_MASK, ht1, chains);
-       if (chains == AR9170_TX_PHY_TXCHAIN_2)
-               ht1 |= AR9170_MAC_BCN_HT1_TX_ANT1;
+       ht_rate = carl9170_tx_beacon_physet(ar, skb, &ht1, &plcp);
 
        carl9170_async_regwrite_begin(ar);
        carl9170_async_regwrite(AR9170_MAC_REG_BCN_HT1, ht1);
-       if (!(txinfo->control.rates[0].flags & IEEE80211_TX_RC_MCS))
-               carl9170_async_regwrite(AR9170_MAC_REG_BCN_PLCP, plcp);
-       else
+       if (ht_rate)
                carl9170_async_regwrite(AR9170_MAC_REG_BCN_HT2, plcp);
+       else
+               carl9170_async_regwrite(AR9170_MAC_REG_BCN_PLCP, plcp);
 
        for (i = 0; i < DIV_ROUND_UP(skb->len, 4); i++) {
                /*