mac80211: Fix rate reporting regression
[linux-2.6] / drivers / net / wireless / iwlwifi / iwl-3945-rs.c
1 /******************************************************************************
2  *
3  * Copyright(c) 2005 - 2007 Intel Corporation. All rights reserved.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms of version 2 of the GNU General Public License as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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12  * more details.
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15  * this program; if not, write to the Free Software Foundation, Inc.,
16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
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18  * The full GNU General Public License is included in this distribution in the
19  * file called LICENSE.
20  *
21  * Contact Information:
22  * James P. Ketrenos <ipw2100-admin@linux.intel.com>
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24  *
25  *****************************************************************************/
26
27 #include <linux/kernel.h>
28 #include <linux/init.h>
29 #include <linux/skbuff.h>
30 #include <linux/wireless.h>
31 #include <net/mac80211.h>
32 #include <net/ieee80211.h>
33
34 #include <linux/netdevice.h>
35 #include <linux/etherdevice.h>
36 #include <linux/delay.h>
37
38 #include <linux/workqueue.h>
39
40 #include "../net/mac80211/ieee80211_rate.h"
41
42 #include "iwl-3945.h"
43
44 #define RS_NAME "iwl-3945-rs"
45
46 struct iwl3945_rate_scale_data {
47         u64 data;
48         s32 success_counter;
49         s32 success_ratio;
50         s32 counter;
51         s32 average_tpt;
52         unsigned long stamp;
53 };
54
55 struct iwl3945_rate_scale_priv {
56         spinlock_t lock;
57         s32 *expected_tpt;
58         unsigned long last_partial_flush;
59         unsigned long last_flush;
60         u32 flush_time;
61         u32 last_tx_packets;
62         u32 tx_packets;
63         u8 tgg;
64         u8 flush_pending;
65         u8 start_rate;
66         u8 ibss_sta_added;
67         struct timer_list rate_scale_flush;
68         struct iwl3945_rate_scale_data win[IWL_RATE_COUNT];
69 };
70
71 static s32 iwl3945_expected_tpt_g[IWL_RATE_COUNT] = {
72         7, 13, 35, 58, 0, 0, 76, 104, 130, 168, 191, 202
73 };
74
75 static s32 iwl3945_expected_tpt_g_prot[IWL_RATE_COUNT] = {
76         7, 13, 35, 58, 0, 0, 0, 80, 93, 113, 123, 125
77 };
78
79 static s32 iwl3945_expected_tpt_a[IWL_RATE_COUNT] = {
80         0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186
81 };
82
83 static s32 iwl3945_expected_tpt_b[IWL_RATE_COUNT] = {
84         7, 13, 35, 58, 0, 0, 0, 0, 0, 0, 0, 0
85 };
86
87 struct iwl3945_tpt_entry {
88         s8 min_rssi;
89         u8 index;
90 };
91
92 static struct iwl3945_tpt_entry iwl3945_tpt_table_a[] = {
93         {-60, IWL_RATE_54M_INDEX},
94         {-64, IWL_RATE_48M_INDEX},
95         {-72, IWL_RATE_36M_INDEX},
96         {-80, IWL_RATE_24M_INDEX},
97         {-84, IWL_RATE_18M_INDEX},
98         {-85, IWL_RATE_12M_INDEX},
99         {-87, IWL_RATE_9M_INDEX},
100         {-89, IWL_RATE_6M_INDEX}
101 };
102
103 static struct iwl3945_tpt_entry iwl3945_tpt_table_b[] = {
104         {-86, IWL_RATE_11M_INDEX},
105         {-88, IWL_RATE_5M_INDEX},
106         {-90, IWL_RATE_2M_INDEX},
107         {-92, IWL_RATE_1M_INDEX}
108
109 };
110
111 static struct iwl3945_tpt_entry iwl3945_tpt_table_g[] = {
112         {-60, IWL_RATE_54M_INDEX},
113         {-64, IWL_RATE_48M_INDEX},
114         {-68, IWL_RATE_36M_INDEX},
115         {-80, IWL_RATE_24M_INDEX},
116         {-84, IWL_RATE_18M_INDEX},
117         {-85, IWL_RATE_12M_INDEX},
118         {-86, IWL_RATE_11M_INDEX},
119         {-88, IWL_RATE_5M_INDEX},
120         {-90, IWL_RATE_2M_INDEX},
121         {-92, IWL_RATE_1M_INDEX}
122 };
123
124 #define IWL_RATE_MAX_WINDOW          62
125 #define IWL_RATE_FLUSH        (3*HZ/10)
126 #define IWL_RATE_WIN_FLUSH       (HZ/2)
127 #define IWL_RATE_HIGH_TH          11520
128 #define IWL_RATE_MIN_FAILURE_TH       8
129 #define IWL_RATE_MIN_SUCCESS_TH       8
130 #define IWL_RATE_DECREASE_TH       1920
131
132 static u8 iwl3945_get_rate_index_by_rssi(s32 rssi, u8 mode)
133 {
134         u32 index = 0;
135         u32 table_size = 0;
136         struct iwl3945_tpt_entry *tpt_table = NULL;
137
138         if ((rssi < IWL_MIN_RSSI_VAL) || (rssi > IWL_MAX_RSSI_VAL))
139                 rssi = IWL_MIN_RSSI_VAL;
140
141         switch (mode) {
142         case MODE_IEEE80211G:
143                 tpt_table = iwl3945_tpt_table_g;
144                 table_size = ARRAY_SIZE(iwl3945_tpt_table_g);
145                 break;
146
147         case MODE_IEEE80211A:
148                 tpt_table = iwl3945_tpt_table_a;
149                 table_size = ARRAY_SIZE(iwl3945_tpt_table_a);
150                 break;
151
152         default:
153         case MODE_IEEE80211B:
154                 tpt_table = iwl3945_tpt_table_b;
155                 table_size = ARRAY_SIZE(iwl3945_tpt_table_b);
156                 break;
157         }
158
159         while ((index < table_size) && (rssi < tpt_table[index].min_rssi))
160                 index++;
161
162         index = min(index, (table_size - 1));
163
164         return tpt_table[index].index;
165 }
166
167 static void iwl3945_clear_window(struct iwl3945_rate_scale_data *window)
168 {
169         window->data = 0;
170         window->success_counter = 0;
171         window->success_ratio = IWL_INVALID_VALUE;
172         window->counter = 0;
173         window->average_tpt = IWL_INVALID_VALUE;
174         window->stamp = 0;
175 }
176
177 /**
178  * iwl3945_rate_scale_flush_windows - flush out the rate scale windows
179  *
180  * Returns the number of windows that have gathered data but were
181  * not flushed.  If there were any that were not flushed, then
182  * reschedule the rate flushing routine.
183  */
184 static int iwl3945_rate_scale_flush_windows(struct iwl3945_rate_scale_priv *rs_priv)
185 {
186         int unflushed = 0;
187         int i;
188         unsigned long flags;
189
190         /*
191          * For each rate, if we have collected data on that rate
192          * and it has been more than IWL_RATE_WIN_FLUSH
193          * since we flushed, clear out the gathered statistics
194          */
195         for (i = 0; i < IWL_RATE_COUNT; i++) {
196                 if (!rs_priv->win[i].counter)
197                         continue;
198
199                 spin_lock_irqsave(&rs_priv->lock, flags);
200                 if (time_after(jiffies, rs_priv->win[i].stamp +
201                                IWL_RATE_WIN_FLUSH)) {
202                         IWL_DEBUG_RATE("flushing %d samples of rate "
203                                        "index %d\n",
204                                        rs_priv->win[i].counter, i);
205                         iwl3945_clear_window(&rs_priv->win[i]);
206                 } else
207                         unflushed++;
208                 spin_unlock_irqrestore(&rs_priv->lock, flags);
209         }
210
211         return unflushed;
212 }
213
214 #define IWL_RATE_FLUSH_MAX              5000    /* msec */
215 #define IWL_RATE_FLUSH_MIN              50      /* msec */
216
217 static void iwl3945_bg_rate_scale_flush(unsigned long data)
218 {
219         struct iwl3945_rate_scale_priv *rs_priv = (void *)data;
220         int unflushed = 0;
221         unsigned long flags;
222         u32 packet_count, duration, pps;
223
224         IWL_DEBUG_RATE("enter\n");
225
226         unflushed = iwl3945_rate_scale_flush_windows(rs_priv);
227
228         spin_lock_irqsave(&rs_priv->lock, flags);
229
230         rs_priv->flush_pending = 0;
231
232         /* Number of packets Rx'd since last time this timer ran */
233         packet_count = (rs_priv->tx_packets - rs_priv->last_tx_packets) + 1;
234
235         rs_priv->last_tx_packets = rs_priv->tx_packets + 1;
236
237         if (unflushed) {
238                 duration =
239                     jiffies_to_msecs(jiffies - rs_priv->last_partial_flush);
240 /*              duration = jiffies_to_msecs(rs_priv->flush_time); */
241
242                 IWL_DEBUG_RATE("Tx'd %d packets in %dms\n",
243                                packet_count, duration);
244
245                 /* Determine packets per second */
246                 if (duration)
247                         pps = (packet_count * 1000) / duration;
248                 else
249                         pps = 0;
250
251                 if (pps) {
252                         duration = IWL_RATE_FLUSH_MAX / pps;
253                         if (duration < IWL_RATE_FLUSH_MIN)
254                                 duration = IWL_RATE_FLUSH_MIN;
255                 } else
256                         duration = IWL_RATE_FLUSH_MAX;
257
258                 rs_priv->flush_time = msecs_to_jiffies(duration);
259
260                 IWL_DEBUG_RATE("new flush period: %d msec ave %d\n",
261                                duration, packet_count);
262
263                 mod_timer(&rs_priv->rate_scale_flush, jiffies +
264                           rs_priv->flush_time);
265
266                 rs_priv->last_partial_flush = jiffies;
267         }
268
269         /* If there weren't any unflushed entries, we don't schedule the timer
270          * to run again */
271
272         rs_priv->last_flush = jiffies;
273
274         spin_unlock_irqrestore(&rs_priv->lock, flags);
275
276         IWL_DEBUG_RATE("leave\n");
277 }
278
279 /**
280  * iwl3945_collect_tx_data - Update the success/failure sliding window
281  *
282  * We keep a sliding window of the last 64 packets transmitted
283  * at this rate.  window->data contains the bitmask of successful
284  * packets.
285  */
286 static void iwl3945_collect_tx_data(struct iwl3945_rate_scale_priv *rs_priv,
287                                 struct iwl3945_rate_scale_data *window,
288                                 int success, int retries)
289 {
290         unsigned long flags;
291
292         if (!retries) {
293                 IWL_DEBUG_RATE("leave: retries == 0 -- should be at least 1\n");
294                 return;
295         }
296
297         while (retries--) {
298                 spin_lock_irqsave(&rs_priv->lock, flags);
299
300                 /* If we have filled up the window then subtract one from the
301                  * success counter if the high-bit is counting toward
302                  * success */
303                 if (window->counter == IWL_RATE_MAX_WINDOW) {
304                         if (window->data & (1ULL << (IWL_RATE_MAX_WINDOW - 1)))
305                                 window->success_counter--;
306                 } else
307                         window->counter++;
308
309                 /* Slide the window to the left one bit */
310                 window->data = (window->data << 1);
311
312                 /* If this packet was a success then set the low bit high */
313                 if (success) {
314                         window->success_counter++;
315                         window->data |= 1;
316                 }
317
318                 /* window->counter can't be 0 -- it is either >0 or
319                  * IWL_RATE_MAX_WINDOW */
320                 window->success_ratio = 12800 * window->success_counter /
321                     window->counter;
322
323                 /* Tag this window as having been updated */
324                 window->stamp = jiffies;
325
326                 spin_unlock_irqrestore(&rs_priv->lock, flags);
327         }
328 }
329
330 static void rs_rate_init(void *priv_rate, void *priv_sta,
331                          struct ieee80211_local *local, struct sta_info *sta)
332 {
333         int i;
334
335         IWL_DEBUG_RATE("enter\n");
336
337         /* TODO: what is a good starting rate for STA? About middle? Maybe not
338          * the lowest or the highest rate.. Could consider using RSSI from
339          * previous packets? Need to have IEEE 802.1X auth succeed immediately
340          * after assoc.. */
341
342         for (i = IWL_RATE_COUNT - 1; i >= 0; i--) {
343                 if (sta->supp_rates & (1 << i)) {
344                         sta->txrate = i;
345                         break;
346                 }
347         }
348
349         sta->last_txrate = sta->txrate;
350
351         /* For MODE_IEEE80211A mode it start at IWL_FIRST_OFDM_RATE */
352         if (local->hw.conf.phymode == MODE_IEEE80211A)
353                 sta->last_txrate += IWL_FIRST_OFDM_RATE;
354
355         IWL_DEBUG_RATE("leave\n");
356 }
357
358 static void *rs_alloc(struct ieee80211_local *local)
359 {
360         return local->hw.priv;
361 }
362
363 /* rate scale requires free function to be implemented */
364 static void rs_free(void *priv)
365 {
366         return;
367 }
368 static void rs_clear(void *priv)
369 {
370         return;
371 }
372
373
374 static void *rs_alloc_sta(void *priv, gfp_t gfp)
375 {
376         struct iwl3945_rate_scale_priv *rs_priv;
377         int i;
378
379         IWL_DEBUG_RATE("enter\n");
380
381         rs_priv = kzalloc(sizeof(struct iwl3945_rate_scale_priv), gfp);
382         if (!rs_priv) {
383                 IWL_DEBUG_RATE("leave: ENOMEM\n");
384                 return NULL;
385         }
386
387         spin_lock_init(&rs_priv->lock);
388
389         rs_priv->start_rate = IWL_RATE_INVALID;
390
391         /* default to just 802.11b */
392         rs_priv->expected_tpt = iwl3945_expected_tpt_b;
393
394         rs_priv->last_partial_flush = jiffies;
395         rs_priv->last_flush = jiffies;
396         rs_priv->flush_time = IWL_RATE_FLUSH;
397         rs_priv->last_tx_packets = 0;
398         rs_priv->ibss_sta_added = 0;
399
400         init_timer(&rs_priv->rate_scale_flush);
401         rs_priv->rate_scale_flush.data = (unsigned long)rs_priv;
402         rs_priv->rate_scale_flush.function = &iwl3945_bg_rate_scale_flush;
403
404         for (i = 0; i < IWL_RATE_COUNT; i++)
405                 iwl3945_clear_window(&rs_priv->win[i]);
406
407         IWL_DEBUG_RATE("leave\n");
408
409         return rs_priv;
410 }
411
412 static void rs_free_sta(void *priv, void *priv_sta)
413 {
414         struct iwl3945_rate_scale_priv *rs_priv = priv_sta;
415
416         IWL_DEBUG_RATE("enter\n");
417         del_timer_sync(&rs_priv->rate_scale_flush);
418         kfree(rs_priv);
419         IWL_DEBUG_RATE("leave\n");
420 }
421
422
423 /*
424  * get ieee prev rate from rate scale table.
425  * for A and B mode we need to overright prev
426  * value
427  */
428 static int rs_adjust_next_rate(struct iwl3945_priv *priv, int rate)
429 {
430         int next_rate = iwl3945_get_prev_ieee_rate(rate);
431
432         switch (priv->phymode) {
433         case MODE_IEEE80211A:
434                 if (rate == IWL_RATE_12M_INDEX)
435                         next_rate = IWL_RATE_9M_INDEX;
436                 else if (rate == IWL_RATE_6M_INDEX)
437                         next_rate = IWL_RATE_6M_INDEX;
438                 break;
439         case MODE_IEEE80211B:
440                 if (rate == IWL_RATE_11M_INDEX_TABLE)
441                         next_rate = IWL_RATE_5M_INDEX_TABLE;
442                 break;
443         default:
444                 break;
445         }
446
447         return next_rate;
448 }
449 /**
450  * rs_tx_status - Update rate control values based on Tx results
451  *
452  * NOTE: Uses iwl3945_priv->retry_rate for the # of retries attempted by
453  * the hardware for each rate.
454  */
455 static void rs_tx_status(void *priv_rate,
456                          struct net_device *dev,
457                          struct sk_buff *skb,
458                          struct ieee80211_tx_status *tx_resp)
459 {
460         u8 retries, current_count;
461         int scale_rate_index, first_index, last_index;
462         unsigned long flags;
463         struct sta_info *sta;
464         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
465         struct iwl3945_priv *priv = (struct iwl3945_priv *)priv_rate;
466         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
467         struct iwl3945_rate_scale_priv *rs_priv;
468
469         IWL_DEBUG_RATE("enter\n");
470
471         retries = tx_resp->retry_count;
472
473         first_index = tx_resp->control.tx_rate;
474         if ((first_index < 0) || (first_index >= IWL_RATE_COUNT)) {
475                 IWL_DEBUG_RATE("leave: Rate out of bounds: %0x for %d\n",
476                                tx_resp->control.tx_rate, first_index);
477                 return;
478         }
479
480         sta = sta_info_get(local, hdr->addr1);
481         if (!sta || !sta->rate_ctrl_priv) {
482                 if (sta)
483                         sta_info_put(sta);
484                 IWL_DEBUG_RATE("leave: No STA priv data to update!\n");
485                 return;
486         }
487
488         rs_priv = (void *)sta->rate_ctrl_priv;
489
490         rs_priv->tx_packets++;
491
492         scale_rate_index = first_index;
493         last_index = first_index;
494
495         /*
496          * Update the window for each rate.  We determine which rates
497          * were Tx'd based on the total number of retries vs. the number
498          * of retries configured for each rate -- currently set to the
499          * priv value 'retry_rate' vs. rate specific
500          *
501          * On exit from this while loop last_index indicates the rate
502          * at which the frame was finally transmitted (or failed if no
503          * ACK)
504          */
505         while (retries > 0) {
506                 if (retries < priv->retry_rate) {
507                         current_count = retries;
508                         last_index = scale_rate_index;
509                 } else {
510                         current_count = priv->retry_rate;
511                         last_index = rs_adjust_next_rate(priv,
512                                                          scale_rate_index);
513                 }
514
515                 /* Update this rate accounting for as many retries
516                  * as was used for it (per current_count) */
517                 iwl3945_collect_tx_data(rs_priv,
518                                     &rs_priv->win[scale_rate_index],
519                                     0, current_count);
520                 IWL_DEBUG_RATE("Update rate %d for %d retries.\n",
521                                scale_rate_index, current_count);
522
523                 retries -= current_count;
524
525                 if (retries)
526                         scale_rate_index =
527                             rs_adjust_next_rate(priv, scale_rate_index);
528         }
529
530
531         /* Update the last index window with success/failure based on ACK */
532         IWL_DEBUG_RATE("Update rate %d with %s.\n",
533                        last_index,
534                        (tx_resp->flags & IEEE80211_TX_STATUS_ACK) ?
535                        "success" : "failure");
536         iwl3945_collect_tx_data(rs_priv,
537                             &rs_priv->win[last_index],
538                             tx_resp->flags & IEEE80211_TX_STATUS_ACK, 1);
539
540         /* We updated the rate scale window -- if its been more than
541          * flush_time since the last run, schedule the flush
542          * again */
543         spin_lock_irqsave(&rs_priv->lock, flags);
544
545         if (!rs_priv->flush_pending &&
546             time_after(jiffies, rs_priv->last_partial_flush +
547                        rs_priv->flush_time)) {
548
549                 rs_priv->flush_pending = 1;
550                 mod_timer(&rs_priv->rate_scale_flush,
551                           jiffies + rs_priv->flush_time);
552         }
553
554         spin_unlock_irqrestore(&rs_priv->lock, flags);
555
556         sta_info_put(sta);
557
558         IWL_DEBUG_RATE("leave\n");
559
560         return;
561 }
562
563 static u16 iwl3945_get_adjacent_rate(struct iwl3945_rate_scale_priv *rs_priv,
564                                      u8 index, u16 rate_mask, int phymode)
565 {
566         u8 high = IWL_RATE_INVALID;
567         u8 low = IWL_RATE_INVALID;
568
569         /* 802.11A walks to the next literal adjacent rate in
570          * the rate table */
571         if (unlikely(phymode == MODE_IEEE80211A)) {
572                 int i;
573                 u32 mask;
574
575                 /* Find the previous rate that is in the rate mask */
576                 i = index - 1;
577                 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
578                         if (rate_mask & mask) {
579                                 low = i;
580                                 break;
581                         }
582                 }
583
584                 /* Find the next rate that is in the rate mask */
585                 i = index + 1;
586                 for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
587                         if (rate_mask & mask) {
588                                 high = i;
589                                 break;
590                         }
591                 }
592
593                 return (high << 8) | low;
594         }
595
596         low = index;
597         while (low != IWL_RATE_INVALID) {
598                 if (rs_priv->tgg)
599                         low = iwl3945_rates[low].prev_rs_tgg;
600                 else
601                         low = iwl3945_rates[low].prev_rs;
602                 if (low == IWL_RATE_INVALID)
603                         break;
604                 if (rate_mask & (1 << low))
605                         break;
606                 IWL_DEBUG_RATE("Skipping masked lower rate: %d\n", low);
607         }
608
609         high = index;
610         while (high != IWL_RATE_INVALID) {
611                 if (rs_priv->tgg)
612                         high = iwl3945_rates[high].next_rs_tgg;
613                 else
614                         high = iwl3945_rates[high].next_rs;
615                 if (high == IWL_RATE_INVALID)
616                         break;
617                 if (rate_mask & (1 << high))
618                         break;
619                 IWL_DEBUG_RATE("Skipping masked higher rate: %d\n", high);
620         }
621
622         return (high << 8) | low;
623 }
624
625 /**
626  * rs_get_rate - find the rate for the requested packet
627  *
628  * Returns the ieee80211_rate structure allocated by the driver.
629  *
630  * The rate control algorithm has no internal mapping between hw_mode's
631  * rate ordering and the rate ordering used by the rate control algorithm.
632  *
633  * The rate control algorithm uses a single table of rates that goes across
634  * the entire A/B/G spectrum vs. being limited to just one particular
635  * hw_mode.
636  *
637  * As such, we can't convert the index obtained below into the hw_mode's
638  * rate table and must reference the driver allocated rate table
639  *
640  */
641 static void rs_get_rate(void *priv_rate, struct net_device *dev,
642                         struct ieee80211_hw_mode *mode, struct sk_buff *skb,
643                         struct rate_selection *sel)
644 {
645         u8 low = IWL_RATE_INVALID;
646         u8 high = IWL_RATE_INVALID;
647         u16 high_low;
648         int index;
649         struct iwl3945_rate_scale_priv *rs_priv;
650         struct iwl3945_rate_scale_data *window = NULL;
651         int current_tpt = IWL_INVALID_VALUE;
652         int low_tpt = IWL_INVALID_VALUE;
653         int high_tpt = IWL_INVALID_VALUE;
654         u32 fail_count;
655         s8 scale_action = 0;
656         unsigned long flags;
657         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
658         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
659         struct sta_info *sta;
660         u16 fc, rate_mask;
661         struct iwl3945_priv *priv = (struct iwl3945_priv *)priv_rate;
662         DECLARE_MAC_BUF(mac);
663
664         IWL_DEBUG_RATE("enter\n");
665
666         sta = sta_info_get(local, hdr->addr1);
667
668         /* Send management frames and broadcast/multicast data using lowest
669          * rate. */
670         fc = le16_to_cpu(hdr->frame_control);
671         if ((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA ||
672             is_multicast_ether_addr(hdr->addr1) ||
673             !sta || !sta->rate_ctrl_priv) {
674                 IWL_DEBUG_RATE("leave: No STA priv data to update!\n");
675                 sel->rate = rate_lowest(local, local->oper_hw_mode, sta);
676                 if (sta)
677                         sta_info_put(sta);
678                 return;
679         }
680
681         rate_mask = sta->supp_rates;
682         index = min(sta->last_txrate & 0xffff, IWL_RATE_COUNT - 1);
683
684         if (priv->phymode == (u8) MODE_IEEE80211A)
685                 rate_mask = rate_mask << IWL_FIRST_OFDM_RATE;
686
687         rs_priv = (void *)sta->rate_ctrl_priv;
688
689         if ((priv->iw_mode == IEEE80211_IF_TYPE_IBSS) &&
690             !rs_priv->ibss_sta_added) {
691                 u8 sta_id = iwl3945_hw_find_station(priv, hdr->addr1);
692
693                 if (sta_id == IWL_INVALID_STATION) {
694                         IWL_DEBUG_RATE("LQ: ADD station %s\n",
695                                        print_mac(mac, hdr->addr1));
696                         sta_id = iwl3945_add_station(priv,
697                                     hdr->addr1, 0, CMD_ASYNC);
698                 }
699                 if (sta_id != IWL_INVALID_STATION)
700                         rs_priv->ibss_sta_added = 1;
701         }
702
703         spin_lock_irqsave(&rs_priv->lock, flags);
704
705         if (rs_priv->start_rate != IWL_RATE_INVALID) {
706                 index = rs_priv->start_rate;
707                 rs_priv->start_rate = IWL_RATE_INVALID;
708         }
709
710         window = &(rs_priv->win[index]);
711
712         fail_count = window->counter - window->success_counter;
713
714         if (((fail_count <= IWL_RATE_MIN_FAILURE_TH) &&
715              (window->success_counter < IWL_RATE_MIN_SUCCESS_TH))) {
716                 window->average_tpt = IWL_INVALID_VALUE;
717                 spin_unlock_irqrestore(&rs_priv->lock, flags);
718
719                 IWL_DEBUG_RATE("Invalid average_tpt on rate %d: "
720                                "counter: %d, success_counter: %d, "
721                                "expected_tpt is %sNULL\n",
722                                index,
723                                window->counter,
724                                window->success_counter,
725                                rs_priv->expected_tpt ? "not " : "");
726                 goto out;
727
728         }
729
730         window->average_tpt = ((window->success_ratio *
731                                 rs_priv->expected_tpt[index] + 64) / 128);
732         current_tpt = window->average_tpt;
733
734         high_low = iwl3945_get_adjacent_rate(rs_priv, index, rate_mask,
735                                          local->hw.conf.phymode);
736         low = high_low & 0xff;
737         high = (high_low >> 8) & 0xff;
738
739         if (low != IWL_RATE_INVALID)
740                 low_tpt = rs_priv->win[low].average_tpt;
741
742         if (high != IWL_RATE_INVALID)
743                 high_tpt = rs_priv->win[high].average_tpt;
744
745         spin_unlock_irqrestore(&rs_priv->lock, flags);
746
747         scale_action = 1;
748
749         if ((window->success_ratio < IWL_RATE_DECREASE_TH) || !current_tpt) {
750                 IWL_DEBUG_RATE("decrease rate because of low success_ratio\n");
751                 scale_action = -1;
752         } else if ((low_tpt == IWL_INVALID_VALUE) &&
753                    (high_tpt == IWL_INVALID_VALUE))
754                 scale_action = 1;
755         else if ((low_tpt != IWL_INVALID_VALUE) &&
756                    (high_tpt != IWL_INVALID_VALUE)
757                    && (low_tpt < current_tpt)
758                    && (high_tpt < current_tpt)) {
759                 IWL_DEBUG_RATE("No action -- low [%d] & high [%d] < "
760                                "current_tpt [%d]\n",
761                                low_tpt, high_tpt, current_tpt);
762                 scale_action = 0;
763         } else {
764                 if (high_tpt != IWL_INVALID_VALUE) {
765                         if (high_tpt > current_tpt)
766                                 scale_action = 1;
767                         else {
768                                 IWL_DEBUG_RATE
769                                     ("decrease rate because of high tpt\n");
770                                 scale_action = -1;
771                         }
772                 } else if (low_tpt != IWL_INVALID_VALUE) {
773                         if (low_tpt > current_tpt) {
774                                 IWL_DEBUG_RATE
775                                     ("decrease rate because of low tpt\n");
776                                 scale_action = -1;
777                         } else
778                                 scale_action = 1;
779                 }
780         }
781
782         if ((window->success_ratio > IWL_RATE_HIGH_TH) ||
783             (current_tpt > window->average_tpt)) {
784                 IWL_DEBUG_RATE("No action -- success_ratio [%d] > HIGH_TH or "
785                                "current_tpt [%d] > average_tpt [%d]\n",
786                                window->success_ratio,
787                                current_tpt, window->average_tpt);
788                 scale_action = 0;
789         }
790
791         switch (scale_action) {
792         case -1:
793                 if (low != IWL_RATE_INVALID)
794                         index = low;
795                 break;
796
797         case 1:
798                 if (high != IWL_RATE_INVALID)
799                         index = high;
800
801                 break;
802
803         case 0:
804         default:
805                 break;
806         }
807
808         IWL_DEBUG_RATE("Selected %d (action %d) - low %d high %d\n",
809                        index, scale_action, low, high);
810
811  out:
812
813         sta->last_txrate = index;
814         if (priv->phymode == (u8) MODE_IEEE80211A)
815                 sta->txrate = sta->last_txrate - IWL_FIRST_OFDM_RATE;
816         else
817                 sta->txrate = sta->last_txrate;
818
819         sta_info_put(sta);
820
821         IWL_DEBUG_RATE("leave: %d\n", index);
822
823         sel->rate = &priv->ieee_rates[index];
824 }
825
826 static struct rate_control_ops rs_ops = {
827         .module = NULL,
828         .name = RS_NAME,
829         .tx_status = rs_tx_status,
830         .get_rate = rs_get_rate,
831         .rate_init = rs_rate_init,
832         .clear = rs_clear,
833         .alloc = rs_alloc,
834         .free = rs_free,
835         .alloc_sta = rs_alloc_sta,
836         .free_sta = rs_free_sta,
837 };
838
839 int iwl3945_fill_rs_info(struct ieee80211_hw *hw, char *buf, u8 sta_id)
840 {
841         struct ieee80211_local *local = hw_to_local(hw);
842         struct iwl3945_priv *priv = hw->priv;
843         struct iwl3945_rate_scale_priv *rs_priv;
844         struct sta_info *sta;
845         unsigned long flags;
846         int count = 0, i;
847         u32 samples = 0, success = 0, good = 0;
848         unsigned long now = jiffies;
849         u32 max_time = 0;
850
851         sta = sta_info_get(local, priv->stations[sta_id].sta.sta.addr);
852         if (!sta || !sta->rate_ctrl_priv) {
853                 if (sta) {
854                         sta_info_put(sta);
855                         IWL_DEBUG_RATE("leave - no private rate data!\n");
856                 } else
857                         IWL_DEBUG_RATE("leave - no station!\n");
858                 return sprintf(buf, "station %d not found\n", sta_id);
859         }
860
861         rs_priv = (void *)sta->rate_ctrl_priv;
862         spin_lock_irqsave(&rs_priv->lock, flags);
863         i = IWL_RATE_54M_INDEX;
864         while (1) {
865                 u64 mask;
866                 int j;
867
868                 count +=
869                     sprintf(&buf[count], " %2dMbs: ", iwl3945_rates[i].ieee / 2);
870
871                 mask = (1ULL << (IWL_RATE_MAX_WINDOW - 1));
872                 for (j = 0; j < IWL_RATE_MAX_WINDOW; j++, mask >>= 1)
873                         buf[count++] =
874                             (rs_priv->win[i].data & mask) ? '1' : '0';
875
876                 samples += rs_priv->win[i].counter;
877                 good += rs_priv->win[i].success_counter;
878                 success += rs_priv->win[i].success_counter * iwl3945_rates[i].ieee;
879
880                 if (rs_priv->win[i].stamp) {
881                         int delta =
882                             jiffies_to_msecs(now - rs_priv->win[i].stamp);
883
884                         if (delta > max_time)
885                                 max_time = delta;
886
887                         count += sprintf(&buf[count], "%5dms\n", delta);
888                 } else
889                         buf[count++] = '\n';
890
891                 j = iwl3945_get_prev_ieee_rate(i);
892                 if (j == i)
893                         break;
894                 i = j;
895         }
896         spin_unlock_irqrestore(&rs_priv->lock, flags);
897         sta_info_put(sta);
898
899         /* Display the average rate of all samples taken.
900          *
901          * NOTE:  We multiple # of samples by 2 since the IEEE measurement
902          * added from iwl3945_rates is actually 2X the rate */
903         if (samples)
904                 count += sprintf(
905                         &buf[count],
906                         "\nAverage rate is %3d.%02dMbs over last %4dms\n"
907                         "%3d%% success (%d good packets over %d tries)\n",
908                         success / (2 * samples), (success * 5 / samples) % 10,
909                         max_time, good * 100 / samples, good, samples);
910         else
911                 count += sprintf(&buf[count], "\nAverage rate: 0Mbs\n");
912
913         return count;
914 }
915
916 void iwl3945_rate_scale_init(struct ieee80211_hw *hw, s32 sta_id)
917 {
918         struct iwl3945_priv *priv = hw->priv;
919         s32 rssi = 0;
920         unsigned long flags;
921         struct ieee80211_local *local = hw_to_local(hw);
922         struct iwl3945_rate_scale_priv *rs_priv;
923         struct sta_info *sta;
924
925         IWL_DEBUG_RATE("enter\n");
926
927         if (!local->rate_ctrl->ops->name ||
928             strcmp(local->rate_ctrl->ops->name, RS_NAME)) {
929                 IWL_WARNING("iwl-3945-rs not selected as rate control algo!\n");
930                 IWL_DEBUG_RATE("leave - mac80211 picked the wrong RC algo.\n");
931                 return;
932         }
933
934         sta = sta_info_get(local, priv->stations[sta_id].sta.sta.addr);
935         if (!sta || !sta->rate_ctrl_priv) {
936                 if (sta)
937                         sta_info_put(sta);
938                 IWL_DEBUG_RATE("leave - no private rate data!\n");
939                 return;
940         }
941
942         rs_priv = (void *)sta->rate_ctrl_priv;
943
944         spin_lock_irqsave(&rs_priv->lock, flags);
945
946         rs_priv->tgg = 0;
947         switch (priv->phymode) {
948         case MODE_IEEE80211G:
949                 if (priv->active_rxon.flags & RXON_FLG_TGG_PROTECT_MSK) {
950                         rs_priv->tgg = 1;
951                         rs_priv->expected_tpt = iwl3945_expected_tpt_g_prot;
952                 } else
953                         rs_priv->expected_tpt = iwl3945_expected_tpt_g;
954                 break;
955
956         case MODE_IEEE80211A:
957                 rs_priv->expected_tpt = iwl3945_expected_tpt_a;
958                 break;
959
960         default:
961                 IWL_WARNING("Invalid phymode.  Defaulting to 802.11b\n");
962         case MODE_IEEE80211B:
963                 rs_priv->expected_tpt = iwl3945_expected_tpt_b;
964                 break;
965         }
966
967         sta_info_put(sta);
968         spin_unlock_irqrestore(&rs_priv->lock, flags);
969
970         rssi = priv->last_rx_rssi;
971         if (rssi == 0)
972                 rssi = IWL_MIN_RSSI_VAL;
973
974         IWL_DEBUG(IWL_DL_INFO | IWL_DL_RATE, "Network RSSI: %d\n", rssi);
975
976         rs_priv->start_rate = iwl3945_get_rate_index_by_rssi(rssi, priv->phymode);
977
978         IWL_DEBUG_RATE("leave: rssi %d assign rate index: "
979                        "%d (plcp 0x%x)\n", rssi, rs_priv->start_rate,
980                        iwl3945_rates[rs_priv->start_rate].plcp);
981 }
982
983 void iwl3945_rate_control_register(struct ieee80211_hw *hw)
984 {
985         ieee80211_rate_control_register(&rs_ops);
986 }
987
988 void iwl3945_rate_control_unregister(struct ieee80211_hw *hw)
989 {
990         ieee80211_rate_control_unregister(&rs_ops);
991 }
992
993