mac80211: clean up rate selection

Move some code out of rc80211_simple since it's probably needed for all rate
selection algorithms, and fix iwlwifi accordingly. While at it, clean up the
rate_control_get_rate() interface.

Signed-off-by: Stefano Brivio <stefano.brivio@polimi.it>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/mac80211/ieee80211_sta.c b/net/mac80211/ieee80211_sta.c
index 3c552fe..3978ad6 100644
--- a/net/mac80211/ieee80211_sta.c
+++ b/net/mac80211/ieee80211_sta.c
@@ -2463,9 +2463,8 @@
 	struct sk_buff *skb;
 	struct ieee80211_mgmt *mgmt;
 	struct ieee80211_tx_control control;
-	struct ieee80211_rate *rate;
 	struct ieee80211_hw_mode *mode;
-	struct rate_control_extra extra;
+	struct rate_selection ratesel;
 	u8 *pos;
 	struct ieee80211_sub_if_data *sdata;
 
@@ -2550,18 +2549,16 @@
 		}
 
 		memset(&control, 0, sizeof(control));
-		memset(&extra, 0, sizeof(extra));
-		extra.mode = local->oper_hw_mode;
-		rate = rate_control_get_rate(local, dev, skb, &extra);
-		if (!rate) {
+		rate_control_get_rate(dev, local->oper_hw_mode, skb, &ratesel);
+		if (!ratesel.rate) {
 			printk(KERN_DEBUG "%s: Failed to determine TX rate "
 			       "for IBSS beacon\n", dev->name);
 			break;
 		}
 		control.tx_rate =
 			((sdata->flags & IEEE80211_SDATA_SHORT_PREAMBLE) &&
-			(rate->flags & IEEE80211_RATE_PREAMBLE2)) ?
-			rate->val2 : rate->val;
+			(ratesel.rate->flags & IEEE80211_RATE_PREAMBLE2)) ?
+			ratesel.rate->val2 : ratesel.rate->val;
 		control.antenna_sel_tx = local->hw.conf.antenna_sel_tx;
 		control.power_level = local->hw.conf.power_level;
 		control.flags |= IEEE80211_TXCTL_NO_ACK;