iwlwifi: implement new mac80211 station add/remove calls

mac80211 recently implemented two new callbacks that are used to request
station add/remove from the driver. The benefot from these new callbacks
are that they enable the driver to sleep while performing this work.

This is a big patch since a few things need to be coordinated in this move.
First we need to decouple station management from rate scaling, which
caused a lot of code to be moved and/or deleted. Next we needed to tie in
with mac80211's station management callback and let it direct our station
management as well as trigger the rate scaling initialization.

Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>

1 files changed, 61 insertions, 59 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-agn-rs.c b/drivers/net/wireless/iwlwifi/iwl-agn-rs.c
index 84271cc62af..970eec82d10 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn-rs.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn-rs.c
@@ -769,6 +769,15 @@ static void rs_tx_status(void *priv_r, struct ieee80211_supported_band *sband,
 
 	IWL_DEBUG_RATE_LIMIT(priv, "get frame ack response, update rate scale window\n");
 
+	/* Treat uninitialized rate scaling data same as non-existing. */
+	if (!lq_sta) {
+		IWL_DEBUG_RATE(priv, "Station rate scaling not created yet.\n");
+		return;
+	} else if (!lq_sta->drv) {
+		IWL_DEBUG_RATE(priv, "Rate scaling not initialized yet.\n");
+		return;
+	}
+
 	if (!ieee80211_is_data(hdr->frame_control) ||
 	    info->flags & IEEE80211_TX_CTL_NO_ACK)
 		return;
@@ -778,10 +787,6 @@ static void rs_tx_status(void *priv_r, struct ieee80211_supported_band *sband,
 	    !(info->flags & IEEE80211_TX_STAT_AMPDU))
 		return;
 
-	if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
-	    !lq_sta->ibss_sta_added)
-		return;
-
 	/*
 	 * Ignore this Tx frame response if its initial rate doesn't match
 	 * that of latest Link Quality command.  There may be stragglers
@@ -827,7 +832,7 @@ static void rs_tx_status(void *priv_r, struct ieee80211_supported_band *sband,
 		lq_sta->missed_rate_counter++;
 		if (lq_sta->missed_rate_counter > IWL_MISSED_RATE_MAX) {
 			lq_sta->missed_rate_counter = 0;
-			iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
+			iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC, false);
 		}
 		/* Regardless, ignore this status info for outdated rate */
 		return;
@@ -1915,7 +1920,7 @@ static u32 rs_update_rate_tbl(struct iwl_priv *priv,
 	/* Update uCode's rate table. */
 	rate = rate_n_flags_from_tbl(priv, tbl, index, is_green);
 	rs_fill_link_cmd(priv, lq_sta, rate);
-	iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
+	iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC, false);
 
 	return rate;
 }
@@ -2291,7 +2296,7 @@ lq_update:
 			IWL_DEBUG_RATE(priv, "Switch current  mcs: %X index: %d\n",
 				     tbl->current_rate, index);
 			rs_fill_link_cmd(priv, lq_sta, tbl->current_rate);
-			iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
+			iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC, false);
 		} else
 			done_search = 1;
 	}
@@ -2340,7 +2345,20 @@ out:
 	return;
 }
 
-
+/**
+ * rs_initialize_lq - Initialize a station's hardware rate table
+ *
+ * The uCode's station table contains a table of fallback rates
+ * for automatic fallback during transmission.
+ *
+ * NOTE: This sets up a default set of values.  These will be replaced later
+ *       if the driver's iwl-agn-rs rate scaling algorithm is used, instead of
+ *       rc80211_simple.
+ *
+ * NOTE: Run REPLY_ADD_STA command to set up station table entry, before
+ *       calling this function (which runs REPLY_TX_LINK_QUALITY_CMD,
+ *       which requires station table entry to exist).
+ */
 static void rs_initialize_lq(struct iwl_priv *priv,
 			     struct ieee80211_conf *conf,
 			     struct ieee80211_sta *sta,
@@ -2390,7 +2408,8 @@ static void rs_initialize_lq(struct iwl_priv *priv,
 	tbl->current_rate = rate;
 	rs_set_expected_tpt_table(lq_sta, tbl);
 	rs_fill_link_cmd(NULL, lq_sta, rate);
-	iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
+	priv->stations[lq_sta->lq.sta_id].lq = &lq_sta->lq;
+	iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_SYNC, true);
  out:
 	return;
 }
@@ -2402,9 +2421,6 @@ static void rs_get_rate(void *priv_r, struct ieee80211_sta *sta, void *priv_sta,
 	struct sk_buff *skb = txrc->skb;
 	struct ieee80211_supported_band *sband = txrc->sband;
 	struct iwl_priv *priv = (struct iwl_priv *)priv_r;
-	struct ieee80211_conf *conf = &priv->hw->conf;
-	struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
-	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 	struct iwl_lq_sta *lq_sta = priv_sta;
 	int rate_idx;
@@ -2422,30 +2438,18 @@ static void rs_get_rate(void *priv_r, struct ieee80211_sta *sta, void *priv_sta,
 			lq_sta->max_rate_idx = -1;
 	}
 
+	/* Treat uninitialized rate scaling data same as non-existing. */
+	if (lq_sta && !lq_sta->drv) {
+		IWL_DEBUG_RATE(priv, "Rate scaling not initialized yet.\n");
+		priv_sta = NULL;
+	}
+
 	/* Send management frames and NO_ACK data using lowest rate. */
 	if (rate_control_send_low(sta, priv_sta, txrc))
 		return;
 
 	rate_idx  = lq_sta->last_txrate_idx;
 
-	if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
-	    !lq_sta->ibss_sta_added) {
-		u8 sta_id = iwl_find_station(priv, hdr->addr1);
-
-		if (sta_id == IWL_INVALID_STATION) {
-			IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n",
-				       hdr->addr1);
-			sta_id = iwl_add_station(priv, hdr->addr1,
-						false, CMD_ASYNC, ht_cap);
-		}
-		if ((sta_id != IWL_INVALID_STATION)) {
-			lq_sta->lq.sta_id = sta_id;
-			lq_sta->lq.rs_table[0].rate_n_flags = 0;
-			lq_sta->ibss_sta_added = 1;
-			rs_initialize_lq(priv, conf, sta, lq_sta);
-		}
-	}
-
 	if (lq_sta->last_rate_n_flags & RATE_MCS_HT_MSK) {
 		rate_idx -= IWL_FIRST_OFDM_RATE;
 		/* 6M and 9M shared same MCS index */
@@ -2495,16 +2499,25 @@ static void *rs_alloc_sta(void *priv_rate, struct ieee80211_sta *sta,
 	return lq_sta;
 }
 
-static void rs_rate_init(void *priv_r, struct ieee80211_supported_band *sband,
-			 struct ieee80211_sta *sta, void *priv_sta)
+/*
+ * Called after adding a new station to initialize rate scaling
+ */
+void iwl_rs_rate_init(struct iwl_priv *priv, struct ieee80211_sta *sta, u8 sta_id)
 {
 	int i, j;
-	struct iwl_priv *priv = (struct iwl_priv *)priv_r;
+	struct ieee80211_hw *hw = priv->hw;
 	struct ieee80211_conf *conf = &priv->hw->conf;
 	struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
-	struct iwl_lq_sta *lq_sta = priv_sta;
+	struct iwl_station_priv *sta_priv;
+	struct iwl_lq_sta *lq_sta;
+	struct ieee80211_supported_band *sband;
+
+	sta_priv = (struct iwl_station_priv *) sta->drv_priv;
+	lq_sta = &sta_priv->lq_sta;
+	sband = hw->wiphy->bands[conf->channel->band];
 
-	lq_sta->lq.sta_id = 0xff;
+
+	lq_sta->lq.sta_id = sta_id;
 
 	for (j = 0; j < LQ_SIZE; j++)
 		for (i = 0; i < IWL_RATE_COUNT; i++)
@@ -2516,33 +2529,13 @@ static void rs_rate_init(void *priv_r, struct ieee80211_supported_band *sband,
 		for (i = 0; i < IWL_RATE_COUNT; i++)
 			rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
 
-	IWL_DEBUG_RATE(priv, "LQ: *** rate scale station global init ***\n");
+	IWL_DEBUG_RATE(priv, "LQ: *** rate scale station global init for station %d ***\n",
+		       sta_id);
 	/* TODO: what is a good starting rate for STA? About middle? Maybe not
 	 * the lowest or the highest rate.. Could consider using RSSI from
 	 * previous packets? Need to have IEEE 802.1X auth succeed immediately
 	 * after assoc.. */
 
-	lq_sta->ibss_sta_added = 0;
-	if (priv->iw_mode == NL80211_IFTYPE_AP) {
-		u8 sta_id = iwl_find_station(priv,
-								sta->addr);
-
-		/* for IBSS the call are from tasklet */
-		IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n", sta->addr);
-
-		if (sta_id == IWL_INVALID_STATION) {
-			IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n", sta->addr);
-			sta_id = iwl_add_station(priv, sta->addr, false,
-						CMD_ASYNC, ht_cap);
-		}
-		if ((sta_id != IWL_INVALID_STATION)) {
-			lq_sta->lq.sta_id = sta_id;
-			lq_sta->lq.rs_table[0].rate_n_flags = 0;
-		}
-		/* FIXME: this is w/a remove it later */
-		priv->assoc_station_added = 1;
-	}
-
 	lq_sta->is_dup = 0;
 	lq_sta->max_rate_idx = -1;
 	lq_sta->missed_rate_counter = IWL_MISSED_RATE_MAX;
@@ -2795,7 +2788,7 @@ static ssize_t rs_sta_dbgfs_scale_table_write(struct file *file,
 
 	if (lq_sta->dbg_fixed_rate) {
 		rs_fill_link_cmd(NULL, lq_sta, lq_sta->dbg_fixed_rate);
-		iwl_send_lq_cmd(lq_sta->drv, &lq_sta->lq, CMD_ASYNC);
+		iwl_send_lq_cmd(lq_sta->drv, &lq_sta->lq, CMD_ASYNC, false);
 	}
 
 	return count;
@@ -2992,12 +2985,21 @@ static void rs_remove_debugfs(void *priv, void *priv_sta)
 }
 #endif
 
+/*
+ * Initialization of rate scaling information is done by driver after
+ * the station is added. Since mac80211 calls this function before a
+ * station is added we ignore it.
+ */
+static void rs_rate_init_stub(void *priv_r, struct ieee80211_supported_band *sband,
+			 struct ieee80211_sta *sta, void *priv_sta)
+{
+}
 static struct rate_control_ops rs_ops = {
 	.module = NULL,
 	.name = RS_NAME,
 	.tx_status = rs_tx_status,
 	.get_rate = rs_get_rate,
-	.rate_init = rs_rate_init,
+	.rate_init = rs_rate_init_stub,
 	.alloc = rs_alloc,
 	.free = rs_free,
 	.alloc_sta = rs_alloc_sta,