[IWLWIFI]: add iwlwifi wireless drivers

This patch adds the mac80211 based wireless drivers for the Intel
PRO/Wireless 3945ABG/BG Network Connection and Intel Wireless WiFi
Link AGN (4965) adapters.

[ Move driver into it's own directory -DaveM ]

Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 979 insertions, 0 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-3945-rs.c b/drivers/net/wireless/iwlwifi/iwl-3945-rs.c
new file mode 100644
index 000000000000..a4f4c8798a83
--- /dev/null
+++ b/drivers/net/wireless/iwlwifi/iwl-3945-rs.c
@@ -0,0 +1,979 @@
+/******************************************************************************
+ *
+ * Copyright(c) 2005 - 2007 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
+ *
+ * The full GNU General Public License is included in this distribution in the
+ * file called LICENSE.
+ *
+ * Contact Information:
+ * James P. Ketrenos <ipw2100-admin@linux.intel.com>
+ * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
+ *
+ *****************************************************************************/
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/skbuff.h>
+#include <linux/wireless.h>
+#include <net/mac80211.h>
+#include <net/ieee80211.h>
+
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/delay.h>
+
+#include <linux/workqueue.h>
+
+#include <net/mac80211.h>
+#include <linux/wireless.h>
+
+#include "../net/mac80211/ieee80211_rate.h"
+
+#include "iwlwifi.h"
+
+#define RS_NAME "iwl-3945-rs"
+
+struct iwl_rate_scale_data {
+	u64 data;
+	s32 success_counter;
+	s32 success_ratio;
+	s32 counter;
+	s32 average_tpt;
+	unsigned long stamp;
+};
+
+struct iwl_rate_scale_priv {
+	spinlock_t lock;
+	s32 *expected_tpt;
+	unsigned long last_partial_flush;
+	unsigned long last_flush;
+	u32 flush_time;
+	u32 last_tx_packets;
+	u32 tx_packets;
+	u8 tgg;
+	u8 flush_pending;
+	u8 start_rate;
+	u8 ibss_sta_added;
+	struct timer_list rate_scale_flush;
+	struct iwl_rate_scale_data win[IWL_RATE_COUNT];
+};
+
+static s32 iwl_expected_tpt_g[IWL_RATE_COUNT] = {
+	0, 0, 76, 104, 130, 168, 191, 202, 7, 13, 35, 58
+};
+
+static s32 iwl_expected_tpt_g_prot[IWL_RATE_COUNT] = {
+	0, 0, 0, 80, 93, 113, 123, 125, 7, 13, 35, 58
+};
+
+static s32 iwl_expected_tpt_a[IWL_RATE_COUNT] = {
+	40, 57, 72, 98, 121, 154, 177, 186, 0, 0, 0, 0
+};
+
+static s32 iwl_expected_tpt_b[IWL_RATE_COUNT] = {
+	0, 0, 0, 0, 0, 0, 0, 0, 7, 13, 35, 58
+};
+
+struct iwl_tpt_entry {
+	s8 min_rssi;
+	u8 index;
+};
+
+static struct iwl_tpt_entry iwl_tpt_table_a[] = {
+	{-60, IWL_RATE_54M_INDEX},
+	{-64, IWL_RATE_48M_INDEX},
+	{-72, IWL_RATE_36M_INDEX},
+	{-80, IWL_RATE_24M_INDEX},
+	{-84, IWL_RATE_18M_INDEX},
+	{-85, IWL_RATE_12M_INDEX},
+	{-87, IWL_RATE_9M_INDEX},
+	{-89, IWL_RATE_6M_INDEX}
+};
+
+static struct iwl_tpt_entry iwl_tpt_table_b[] = {
+	{-86, IWL_RATE_11M_INDEX},
+	{-88, IWL_RATE_5M_INDEX},
+	{-90, IWL_RATE_2M_INDEX},
+	{-92, IWL_RATE_1M_INDEX}
+
+};
+
+static struct iwl_tpt_entry iwl_tpt_table_g[] = {
+	{-60, IWL_RATE_54M_INDEX},
+	{-64, IWL_RATE_48M_INDEX},
+	{-68, IWL_RATE_36M_INDEX},
+	{-80, IWL_RATE_24M_INDEX},
+	{-84, IWL_RATE_18M_INDEX},
+	{-85, IWL_RATE_12M_INDEX},
+	{-86, IWL_RATE_11M_INDEX},
+	{-88, IWL_RATE_5M_INDEX},
+	{-90, IWL_RATE_2M_INDEX},
+	{-92, IWL_RATE_1M_INDEX}
+};
+
+#define IWL_RATE_MAX_WINDOW          62
+#define IWL_RATE_FLUSH        (3*HZ/10)
+#define IWL_RATE_WIN_FLUSH       (HZ/2)
+#define IWL_RATE_HIGH_TH          11520
+#define IWL_RATE_MIN_FAILURE_TH       8
+#define IWL_RATE_MIN_SUCCESS_TH       8
+#define IWL_RATE_DECREASE_TH       1920
+
+static u8 iwl_get_rate_index_by_rssi(s32 rssi, u8 mode)
+{
+	u32 index = 0;
+	u32 table_size = 0;
+	struct iwl_tpt_entry *tpt_table = NULL;
+
+	if ((rssi < IWL_MIN_RSSI_VAL) || (rssi > IWL_MAX_RSSI_VAL))
+		rssi = IWL_MIN_RSSI_VAL;
+
+	switch (mode) {
+	case MODE_IEEE80211G:
+		tpt_table = iwl_tpt_table_g;
+		table_size = ARRAY_SIZE(iwl_tpt_table_g);
+		break;
+
+	case MODE_IEEE80211A:
+		tpt_table = iwl_tpt_table_a;
+		table_size = ARRAY_SIZE(iwl_tpt_table_a);
+		break;
+
+	default:
+	case MODE_IEEE80211B:
+		tpt_table = iwl_tpt_table_b;
+		table_size = ARRAY_SIZE(iwl_tpt_table_b);
+		break;
+	}
+
+	while ((index < table_size) && (rssi < tpt_table[index].min_rssi))
+		index++;
+
+	index = min(index, (table_size - 1));
+
+	return tpt_table[index].index;
+}
+
+static void iwl_clear_window(struct iwl_rate_scale_data *window)
+{
+	window->data = 0;
+	window->success_counter = 0;
+	window->success_ratio = IWL_INVALID_VALUE;
+	window->counter = 0;
+	window->average_tpt = IWL_INVALID_VALUE;
+	window->stamp = 0;
+}
+
+/**
+ * iwl_rate_scale_flush_windows - flush out the rate scale windows
+ *
+ * Returns the number of windows that have gathered data but were
+ * not flushed.  If there were any that were not flushed, then
+ * reschedule the rate flushing routine.
+ */
+static int iwl_rate_scale_flush_windows(struct iwl_rate_scale_priv *rs_priv)
+{
+	int unflushed = 0;
+	int i;
+	unsigned long flags;
+
+	/*
+	 * For each rate, if we have collected data on that rate
+	 * and it has been more than IWL_RATE_WIN_FLUSH
+	 * since we flushed, clear out the gathered statistics
+	 */
+	for (i = 0; i < IWL_RATE_COUNT; i++) {
+		if (!rs_priv->win[i].counter)
+			continue;
+
+		spin_lock_irqsave(&rs_priv->lock, flags);
+		if (time_after(jiffies, rs_priv->win[i].stamp +
+			       IWL_RATE_WIN_FLUSH)) {
+			IWL_DEBUG_RATE("flushing %d samples of rate "
+				       "index %d\n",
+				       rs_priv->win[i].counter, i);
+			iwl_clear_window(&rs_priv->win[i]);
+		} else
+			unflushed++;
+		spin_unlock_irqrestore(&rs_priv->lock, flags);
+	}
+
+	return unflushed;
+}
+
+#define IWL_RATE_FLUSH_MAX              5000	/* msec */
+#define IWL_RATE_FLUSH_MIN              50	/* msec */
+
+static void iwl_bg_rate_scale_flush(unsigned long data)
+{
+	struct iwl_rate_scale_priv *rs_priv = (void *)data;
+	int unflushed = 0;
+	unsigned long flags;
+	u32 packet_count, duration, pps;
+
+	IWL_DEBUG_RATE("enter\n");
+
+	unflushed = iwl_rate_scale_flush_windows(rs_priv);
+
+	spin_lock_irqsave(&rs_priv->lock, flags);
+
+	rs_priv->flush_pending = 0;
+
+	/* Number of packets Rx'd since last time this timer ran */
+	packet_count = (rs_priv->tx_packets - rs_priv->last_tx_packets) + 1;
+
+	rs_priv->last_tx_packets = rs_priv->tx_packets + 1;
+
+	if (unflushed) {
+		duration =
+		    jiffies_to_msecs(jiffies - rs_priv->last_partial_flush);
+/*              duration = jiffies_to_msecs(rs_priv->flush_time); */
+
+		IWL_DEBUG_RATE("Tx'd %d packets in %dms\n",
+			       packet_count, duration);
+
+		/* Determine packets per second */
+		if (duration)
+			pps = (packet_count * 1000) / duration;
+		else
+			pps = 0;
+
+		if (pps) {
+			duration = IWL_RATE_FLUSH_MAX / pps;
+			if (duration < IWL_RATE_FLUSH_MIN)
+				duration = IWL_RATE_FLUSH_MIN;
+		} else
+			duration = IWL_RATE_FLUSH_MAX;
+
+		rs_priv->flush_time = msecs_to_jiffies(duration);
+
+		IWL_DEBUG_RATE("new flush period: %d msec ave %d\n",
+			       duration, packet_count);
+
+		mod_timer(&rs_priv->rate_scale_flush, jiffies +
+			  rs_priv->flush_time);
+
+		rs_priv->last_partial_flush = jiffies;
+	}
+
+	/* If there weren't any unflushed entries, we don't schedule the timer
+	 * to run again */
+
+	rs_priv->last_flush = jiffies;
+
+	spin_unlock_irqrestore(&rs_priv->lock, flags);
+
+	IWL_DEBUG_RATE("leave\n");
+}
+
+/**
+ * iwl_collect_tx_data - Update the success/failure sliding window
+ *
+ * We keep a sliding window of the last 64 packets transmitted
+ * at this rate.  window->data contains the bitmask of successful
+ * packets.
+ */
+static void iwl_collect_tx_data(struct iwl_rate_scale_priv *rs_priv,
+				struct iwl_rate_scale_data *window,
+				int success, int retries)
+{
+	unsigned long flags;
+
+	if (!retries) {
+		IWL_DEBUG_RATE("leave: retries == 0 -- should be at least 1\n");
+		return;
+	}
+
+	while (retries--) {
+		spin_lock_irqsave(&rs_priv->lock, flags);
+
+		/* If we have filled up the window then subtract one from the
+		 * success counter if the high-bit is counting toward
+		 * success */
+		if (window->counter == IWL_RATE_MAX_WINDOW) {
+			if (window->data & (1ULL << (IWL_RATE_MAX_WINDOW - 1)))
+				window->success_counter--;
+		} else
+			window->counter++;
+
+		/* Slide the window to the left one bit */
+		window->data = (window->data << 1);
+
+		/* If this packet was a success then set the low bit high */
+		if (success) {
+			window->success_counter++;
+			window->data |= 1;
+		}
+
+		/* window->counter can't be 0 -- it is either >0 or
+		 * IWL_RATE_MAX_WINDOW */
+		window->success_ratio = 12800 * window->success_counter /
+		    window->counter;
+
+		/* Tag this window as having been updated */
+		window->stamp = jiffies;
+
+		spin_unlock_irqrestore(&rs_priv->lock, flags);
+	}
+}
+
+static void rs_rate_init(void *priv_rate, void *priv_sta,
+			 struct ieee80211_local *local, struct sta_info *sta)
+{
+	int i;
+
+	IWL_DEBUG_RATE("enter\n");
+
+	/* 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.. */
+
+	for (i = IWL_RATE_COUNT - 1; i >= 0; i--) {
+		if (sta->supp_rates & (1 << i)) {
+			sta->txrate = i;
+			break;
+		}
+	}
+
+	sta->last_txrate = sta->txrate;
+
+	IWL_DEBUG_RATE("leave\n");
+}
+
+static void *rs_alloc(struct ieee80211_local *local)
+{
+	return local->hw.priv;
+}
+
+/* rate scale requires free function to be implmented */
+static void rs_free(void *priv)
+{
+	return;
+}
+static void rs_clear(void *priv)
+{
+	return;
+}
+
+
+static void *rs_alloc_sta(void *priv, gfp_t gfp)
+{
+	struct iwl_rate_scale_priv *rs_priv;
+	int i;
+
+	IWL_DEBUG_RATE("enter\n");
+
+	rs_priv = kzalloc(sizeof(struct iwl_rate_scale_priv), gfp);
+	if (!rs_priv) {
+		IWL_DEBUG_RATE("leave: ENOMEM\n");
+		return NULL;
+	}
+
+	spin_lock_init(&rs_priv->lock);
+
+	rs_priv->start_rate = IWL_RATE_INVALID;
+
+	/* default to just 802.11b */
+	rs_priv->expected_tpt = iwl_expected_tpt_b;
+
+	rs_priv->last_partial_flush = jiffies;
+	rs_priv->last_flush = jiffies;
+	rs_priv->flush_time = IWL_RATE_FLUSH;
+	rs_priv->last_tx_packets = 0;
+	rs_priv->ibss_sta_added = 0;
+
+	init_timer(&rs_priv->rate_scale_flush);
+	rs_priv->rate_scale_flush.data = (unsigned long)rs_priv;
+	rs_priv->rate_scale_flush.function = &iwl_bg_rate_scale_flush;
+
+	for (i = 0; i < IWL_RATE_COUNT; i++)
+		iwl_clear_window(&rs_priv->win[i]);
+
+	IWL_DEBUG_RATE("leave\n");
+
+	return rs_priv;
+}
+
+static void rs_free_sta(void *priv, void *priv_sta)
+{
+	struct iwl_rate_scale_priv *rs_priv = priv_sta;
+
+	IWL_DEBUG_RATE("enter\n");
+	del_timer_sync(&rs_priv->rate_scale_flush);
+	kfree(rs_priv);
+	IWL_DEBUG_RATE("leave\n");
+}
+
+/**
+ * rs_tx_status - Update rate control values based on Tx results
+ *
+ * NOTE: Uses iwl_priv->retry_rate for the # of retries attempted by
+ * the hardware for each rate.
+ */
+static void rs_tx_status(void *priv_rate,
+			 struct net_device *dev,
+			 struct sk_buff *skb,
+			 struct ieee80211_tx_status *tx_resp)
+{
+	u8 retries, current_count;
+	int scale_rate_index, first_index, last_index;
+	unsigned long flags;
+	struct sta_info *sta;
+	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
+	struct iwl_priv *priv = (struct iwl_priv *)priv_rate;
+	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
+	struct iwl_rate_scale_priv *rs_priv;
+
+	IWL_DEBUG_RATE("enter\n");
+
+	retries = tx_resp->retry_count;
+
+	first_index = tx_resp->control.tx_rate;
+	if ((first_index < 0) || (first_index >= IWL_RATE_COUNT)) {
+		IWL_DEBUG_RATE("leave: Rate out of bounds: %0x for %d\n",
+			       tx_resp->control.tx_rate, first_index);
+		return;
+	}
+
+	sta = sta_info_get(local, hdr->addr1);
+	if (!sta || !sta->rate_ctrl_priv) {
+		if (sta)
+			sta_info_put(sta);
+		IWL_DEBUG_RATE("leave: No STA priv data to update!\n");
+		return;
+	}
+
+	rs_priv = (void *)sta->rate_ctrl_priv;
+
+	rs_priv->tx_packets++;
+
+	scale_rate_index = first_index;
+	last_index = first_index;
+
+	/*
+	 * Update the window for each rate.  We determine which rates
+	 * were Tx'd based on the total number of retries vs. the number
+	 * of retries configured for each rate -- currently set to the
+	 * priv value 'retry_rate' vs. rate specific
+	 *
+	 * On exit from this while loop last_index indicates the rate
+	 * at which the frame was finally transmitted (or failed if no
+	 * ACK)
+	 */
+	while (retries > 0) {
+		if (retries < priv->retry_rate) {
+			current_count = retries;
+			last_index = scale_rate_index;
+		} else {
+			current_count = priv->retry_rate;
+			last_index = iwl_get_prev_ieee_rate(scale_rate_index);
+		}
+
+		/* Update this rate accounting for as many retries
+		 * as was used for it (per current_count) */
+		iwl_collect_tx_data(rs_priv,
+				    &rs_priv->win[scale_rate_index],
+				    0, current_count);
+		IWL_DEBUG_RATE("Update rate %d for %d retries.\n",
+			       scale_rate_index, current_count);
+
+		retries -= current_count;
+
+		if (retries)
+			scale_rate_index =
+			    iwl_get_prev_ieee_rate(scale_rate_index);
+	}
+
+	/* Update the last index window with success/failure based on ACK */
+	IWL_DEBUG_RATE("Update rate %d with %s.\n",
+		       last_index,
+		       (tx_resp->flags & IEEE80211_TX_STATUS_ACK) ?
+		       "success" : "failure");
+	iwl_collect_tx_data(rs_priv,
+			    &rs_priv->win[last_index],
+			    tx_resp->flags & IEEE80211_TX_STATUS_ACK, 1);
+
+	/* We updated the rate scale window -- if its been more than
+	 * flush_time since the last run, schedule the flush
+	 * again */
+	spin_lock_irqsave(&rs_priv->lock, flags);
+
+	if (!rs_priv->flush_pending &&
+	    time_after(jiffies, rs_priv->last_partial_flush +
+		       rs_priv->flush_time)) {
+
+		rs_priv->flush_pending = 1;
+		mod_timer(&rs_priv->rate_scale_flush,
+			  jiffies + rs_priv->flush_time);
+	}
+
+	spin_unlock_irqrestore(&rs_priv->lock, flags);
+
+	sta_info_put(sta);
+
+	IWL_DEBUG_RATE("leave\n");
+
+	return;
+}
+
+static struct ieee80211_rate *iwl_get_lowest_rate(struct ieee80211_local
+						  *local)
+{
+	struct ieee80211_hw_mode *mode = local->oper_hw_mode;
+	int i;
+
+	for (i = 0; i < mode->num_rates; i++) {
+		struct ieee80211_rate *rate = &mode->rates[i];
+
+		if (rate->flags & IEEE80211_RATE_SUPPORTED)
+			return rate;
+	}
+
+	return &mode->rates[0];
+}
+
+static u16 iwl_get_adjacent_rate(struct iwl_rate_scale_priv *rs_priv,
+				 u8 index, u16 rate_mask, int phymode)
+{
+	u8 high = IWL_RATE_INVALID;
+	u8 low = IWL_RATE_INVALID;
+
+	/* 802.11A walks to the next literal adjascent rate in
+	 * the rate table */
+	if (unlikely(phymode == MODE_IEEE80211A)) {
+		int i;
+		u32 mask;
+
+		/* Find the previous rate that is in the rate mask */
+		i = index - 1;
+		for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
+			if (rate_mask & mask) {
+				low = i;
+				break;
+			}
+		}
+
+		/* Find the next rate that is in the rate mask */
+		i = index + 1;
+		for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
+			if (rate_mask & mask) {
+				high = i;
+				break;
+			}
+		}
+
+		return (high << 8) | low;
+	}
+
+	low = index;
+	while (low != IWL_RATE_INVALID) {
+		if (rs_priv->tgg)
+			low = iwl_rates[low].prev_rs_tgg;
+		else
+			low = iwl_rates[low].prev_rs;
+		if (low == IWL_RATE_INVALID)
+			break;
+		if (rate_mask & (1 << low))
+			break;
+		IWL_DEBUG_RATE("Skipping masked lower rate: %d\n", low);
+	}
+
+	high = index;
+	while (high != IWL_RATE_INVALID) {
+		if (rs_priv->tgg)
+			high = iwl_rates[high].next_rs_tgg;
+		else
+			high = iwl_rates[high].next_rs;
+		if (high == IWL_RATE_INVALID)
+			break;
+		if (rate_mask & (1 << high))
+			break;
+		IWL_DEBUG_RATE("Skipping masked higher rate: %d\n", high);
+	}
+
+	return (high << 8) | low;
+}
+
+/**
+ * rs_get_rate - find the rate for the requested packet
+ *
+ * Returns the ieee80211_rate structure allocated by the driver.
+ *
+ * The rate control algorithm has no internal mapping between hw_mode's
+ * rate ordering and the rate ordering used by the rate control algorithm.
+ *
+ * The rate control algorithm uses a single table of rates that goes across
+ * the entire A/B/G spectrum vs. being limited to just one particular
+ * hw_mode.
+ *
+ * As such, we can't convert the index obtained below into the hw_mode's
+ * rate table and must reference the driver allocated rate table
+ *
+ */
+static struct ieee80211_rate *rs_get_rate(void *priv_rate,
+					  struct net_device *dev,
+					  struct sk_buff *skb,
+					  struct rate_control_extra *extra)
+{
+	u8 low = IWL_RATE_INVALID;
+	u8 high = IWL_RATE_INVALID;
+	u16 high_low;
+	int index;
+	struct iwl_rate_scale_priv *rs_priv;
+	struct iwl_rate_scale_data *window = NULL;
+	int current_tpt = IWL_INVALID_VALUE;
+	int low_tpt = IWL_INVALID_VALUE;
+	int high_tpt = IWL_INVALID_VALUE;
+	u32 fail_count;
+	s8 scale_action = 0;
+	unsigned long flags;
+	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
+	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
+	struct sta_info *sta;
+	u16 fc, rate_mask;
+	struct iwl_priv *priv = (struct iwl_priv *)priv_rate;
+
+	IWL_DEBUG_RATE("enter\n");
+
+	memset(extra, 0, sizeof(*extra));
+
+	fc = le16_to_cpu(hdr->frame_control);
+	if (((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA) ||
+	    (is_multicast_ether_addr(hdr->addr1))) {
+		/* Send management frames and broadcast/multicast data using
+		 * lowest rate. */
+		/* TODO: this could probably be improved.. */
+		IWL_DEBUG_RATE("leave: lowest rate (not data or is "
+			       "multicast)\n");
+
+		return iwl_get_lowest_rate(local);
+	}
+
+	sta = sta_info_get(local, hdr->addr1);
+	if (!sta || !sta->rate_ctrl_priv) {
+		IWL_DEBUG_RATE("leave: No STA priv data to update!\n");
+		if (sta)
+			sta_info_put(sta);
+		return NULL;
+	}
+
+	rate_mask = sta->supp_rates;
+	index = min(sta->txrate & 0xffff, IWL_RATE_COUNT - 1);
+
+	rs_priv = (void *)sta->rate_ctrl_priv;
+
+	if ((priv->iw_mode == IEEE80211_IF_TYPE_IBSS) &&
+	    !rs_priv->ibss_sta_added) {
+		u8 sta_id = iwl_hw_find_station(priv, hdr->addr1);
+
+		if (sta_id == IWL_INVALID_STATION) {
+			IWL_DEBUG_RATE("LQ: ADD station " MAC_FMT "\n",
+					MAC_ARG(hdr->addr1));
+			sta_id = iwl_add_station(priv,
+				    hdr->addr1, 0, CMD_ASYNC);
+		}
+		if (sta_id != IWL_INVALID_STATION)
+			rs_priv->ibss_sta_added = 1;
+	}
+
+	spin_lock_irqsave(&rs_priv->lock, flags);
+
+	if (rs_priv->start_rate != IWL_RATE_INVALID) {
+		index = rs_priv->start_rate;
+		rs_priv->start_rate = IWL_RATE_INVALID;
+	}
+
+	window = &(rs_priv->win[index]);
+
+	fail_count = window->counter - window->success_counter;
+
+	if (((fail_count <= IWL_RATE_MIN_FAILURE_TH) &&
+	     (window->success_counter < IWL_RATE_MIN_SUCCESS_TH))) {
+		window->average_tpt = IWL_INVALID_VALUE;
+		spin_unlock_irqrestore(&rs_priv->lock, flags);
+
+		IWL_DEBUG_RATE("Invalid average_tpt on rate %d: "
+			       "counter: %d, success_counter: %d, "
+			       "expected_tpt is %sNULL\n",
+			       index,
+			       window->counter,
+			       window->success_counter,
+			       rs_priv->expected_tpt ? "not " : "");
+		goto out;
+
+	}
+
+	window->average_tpt = ((window->success_ratio *
+				rs_priv->expected_tpt[index] + 64) / 128);
+	current_tpt = window->average_tpt;
+
+	high_low = iwl_get_adjacent_rate(rs_priv, index, rate_mask,
+					 local->hw.conf.phymode);
+	low = high_low & 0xff;
+	high = (high_low >> 8) & 0xff;
+
+	if (low != IWL_RATE_INVALID)
+		low_tpt = rs_priv->win[low].average_tpt;
+
+	if (high != IWL_RATE_INVALID)
+		high_tpt = rs_priv->win[high].average_tpt;
+
+	spin_unlock_irqrestore(&rs_priv->lock, flags);
+
+	scale_action = 1;
+
+	if ((window->success_ratio < IWL_RATE_DECREASE_TH) || !current_tpt) {
+		IWL_DEBUG_RATE("decrease rate because of low success_ratio\n");
+		scale_action = -1;
+	} else if ((low_tpt == IWL_INVALID_VALUE) &&
+		   (high_tpt == IWL_INVALID_VALUE))
+		scale_action = 1;
+	else if ((low_tpt != IWL_INVALID_VALUE) &&
+		   (high_tpt != IWL_INVALID_VALUE)
+		   && (low_tpt < current_tpt)
+		   && (high_tpt < current_tpt)) {
+		IWL_DEBUG_RATE("No action -- low [%d] & high [%d] < "
+			       "current_tpt [%d]\n",
+			       low_tpt, high_tpt, current_tpt);
+		scale_action = 0;
+	} else {
+		if (high_tpt != IWL_INVALID_VALUE) {
+			if (high_tpt > current_tpt)
+				scale_action = 1;
+			else {
+				IWL_DEBUG_RATE
+				    ("decrease rate because of high tpt\n");
+				scale_action = -1;
+			}
+		} else if (low_tpt != IWL_INVALID_VALUE) {
+			if (low_tpt > current_tpt) {
+				IWL_DEBUG_RATE
+				    ("decrease rate because of low tpt\n");
+				scale_action = -1;
+			} else
+				scale_action = 1;
+		}
+	}
+
+	if ((window->success_ratio > IWL_RATE_HIGH_TH) ||
+	    (current_tpt > window->average_tpt)) {
+		IWL_DEBUG_RATE("No action -- success_ratio [%d] > HIGH_TH or "
+			       "current_tpt [%d] > average_tpt [%d]\n",
+			       window->success_ratio,
+			       current_tpt, window->average_tpt);
+		scale_action = 0;
+	}
+
+	switch (scale_action) {
+	case -1:
+		if (low != IWL_RATE_INVALID)
+			index = low;
+		break;
+
+	case 1:
+		if (high != IWL_RATE_INVALID)
+			index = high;
+
+		break;
+
+	case 0:
+	default:
+		break;
+	}
+
+	IWL_DEBUG_RATE("Selected %d (action %d) - low %d high %d\n",
+		       index, scale_action, low, high);
+
+ out:
+
+	sta->last_txrate = index;
+	sta->txrate = sta->last_txrate;
+	sta_info_put(sta);
+
+	IWL_DEBUG_RATE("leave: %d\n", index);
+
+	return &priv->ieee_rates[index];
+}
+
+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,
+	.clear = rs_clear,
+	.alloc = rs_alloc,
+	.free = rs_free,
+	.alloc_sta = rs_alloc_sta,
+	.free_sta = rs_free_sta,
+};
+
+int iwl_fill_rs_info(struct ieee80211_hw *hw, char *buf, u8 sta_id)
+{
+	struct ieee80211_local *local = hw_to_local(hw);
+	struct iwl_priv *priv = hw->priv;
+	struct iwl_rate_scale_priv *rs_priv;
+	struct sta_info *sta;
+	unsigned long flags;
+	int count = 0, i;
+	u32 samples = 0, success = 0, good = 0;
+	unsigned long now = jiffies;
+	u32 max_time = 0;
+
+	sta = sta_info_get(local, priv->stations[sta_id].sta.sta.addr);
+	if (!sta || !sta->rate_ctrl_priv) {
+		if (sta) {
+			sta_info_put(sta);
+			IWL_DEBUG_RATE("leave - no private rate data!\n");
+		} else
+			IWL_DEBUG_RATE("leave - no station!\n");
+		return sprintf(buf, "station %d not found\n", sta_id);
+	}
+
+	rs_priv = (void *)sta->rate_ctrl_priv;
+	spin_lock_irqsave(&rs_priv->lock, flags);
+	i = IWL_RATE_54M_INDEX;
+	while (1) {
+		u64 mask;
+		int j;
+
+		count +=
+		    sprintf(&buf[count], " %2dMbs: ", iwl_rates[i].ieee / 2);
+
+		mask = (1ULL << (IWL_RATE_MAX_WINDOW - 1));
+		for (j = 0; j < IWL_RATE_MAX_WINDOW; j++, mask >>= 1)
+			buf[count++] =
+			    (rs_priv->win[i].data & mask) ? '1' : '0';
+
+		samples += rs_priv->win[i].counter;
+		good += rs_priv->win[i].success_counter;
+		success += rs_priv->win[i].success_counter * iwl_rates[i].ieee;
+
+		if (rs_priv->win[i].stamp) {
+			int delta =
+			    jiffies_to_msecs(now - rs_priv->win[i].stamp);
+
+			if (delta > max_time)
+				max_time = delta;
+
+			count += sprintf(&buf[count], "%5dms\n", delta);
+		} else
+			buf[count++] = '\n';
+
+		j = iwl_get_prev_ieee_rate(i);
+		if (j == i)
+			break;
+		i = j;
+	}
+	spin_unlock_irqrestore(&rs_priv->lock, flags);
+	sta_info_put(sta);
+
+	/* Display the average rate of all samples taken.
+	 *
+	 * NOTE:  We multiple # of samples by 2 since the IEEE measurement
+	 * added from iwl_rates is actually 2X the rate */
+	if (samples)
+		count += sprintf(
+			&buf[count],
+			"\nAverage rate is %3d.%02dMbs over last %4dms\n"
+			"%3d%% success (%d good packets over %d tries)\n",
+			success / (2 * samples), (success * 5 / samples) % 10,
+			max_time, good * 100 / samples, good, samples);
+	else
+		count += sprintf(&buf[count], "\nAverage rate: 0Mbs\n");
+
+	return count;
+}
+
+void iwl_rate_scale_init(struct ieee80211_hw *hw, s32 sta_id)
+{
+	struct iwl_priv *priv = hw->priv;
+	s32 rssi = 0;
+	unsigned long flags;
+	struct ieee80211_local *local = hw_to_local(hw);
+	struct iwl_rate_scale_priv *rs_priv;
+	struct sta_info *sta;
+
+	IWL_DEBUG_RATE("enter\n");
+
+	if (!local->rate_ctrl->ops->name ||
+	    strcmp(local->rate_ctrl->ops->name, RS_NAME)) {
+		IWL_WARNING("iwl-3945-rs not selected as rate control algo!\n");
+		IWL_DEBUG_RATE("leave - mac80211 picked the wrong RC algo.\n");
+		return;
+	}
+
+	sta = sta_info_get(local, priv->stations[sta_id].sta.sta.addr);
+	if (!sta || !sta->rate_ctrl_priv) {
+		if (sta)
+			sta_info_put(sta);
+		IWL_DEBUG_RATE("leave - no private rate data!\n");
+		return;
+	}
+
+	rs_priv = (void *)sta->rate_ctrl_priv;
+
+	spin_lock_irqsave(&rs_priv->lock, flags);
+
+	rs_priv->tgg = 0;
+	switch (priv->phymode) {
+	case MODE_IEEE80211G:
+		if (priv->active_rxon.flags & RXON_FLG_TGG_PROTECT_MSK) {
+			rs_priv->tgg = 1;
+			rs_priv->expected_tpt = iwl_expected_tpt_g_prot;
+		} else
+			rs_priv->expected_tpt = iwl_expected_tpt_g;
+		break;
+
+	case MODE_IEEE80211A:
+		rs_priv->expected_tpt = iwl_expected_tpt_a;
+		break;
+
+	default:
+		IWL_WARNING("Invalid phymode.  Defaulting to 802.11b\n");
+	case MODE_IEEE80211B:
+		rs_priv->expected_tpt = iwl_expected_tpt_b;
+		break;
+	}
+
+	sta_info_put(sta);
+	spin_unlock_irqrestore(&rs_priv->lock, flags);
+
+	rssi = priv->last_rx_rssi;
+	if (rssi == 0)
+		rssi = IWL_MIN_RSSI_VAL;
+
+	IWL_DEBUG(IWL_DL_INFO | IWL_DL_RATE, "Network RSSI: %d\n", rssi);
+
+	rs_priv->start_rate = iwl_get_rate_index_by_rssi(rssi, priv->phymode);
+
+	IWL_DEBUG_RATE("leave: rssi %d assign rate index: "
+		       "%d (plcp 0x%x)\n", rssi, rs_priv->start_rate,
+		       iwl_rates[rs_priv->start_rate].plcp);
+}
+
+void iwl_rate_control_register(struct ieee80211_hw *hw)
+{
+	ieee80211_rate_control_register(&rs_ops);
+}
+
+void iwl_rate_control_unregister(struct ieee80211_hw *hw)
+{
+	ieee80211_rate_control_unregister(&rs_ops);
+}
+
+