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Felix Fietkaucccf1292008-10-05 18:07:45 +02001/*
2 * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 *
8 * Based on minstrel.c:
9 * Copyright (C) 2005-2007 Derek Smithies <derek@indranet.co.nz>
10 * Sponsored by Indranet Technologies Ltd
11 *
12 * Based on sample.c:
13 * Copyright (c) 2005 John Bicket
14 * All rights reserved.
15 *
16 * Redistribution and use in source and binary forms, with or without
17 * modification, are permitted provided that the following conditions
18 * are met:
19 * 1. Redistributions of source code must retain the above copyright
20 * notice, this list of conditions and the following disclaimer,
21 * without modification.
22 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
23 * similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
24 * redistribution must be conditioned upon including a substantially
25 * similar Disclaimer requirement for further binary redistribution.
26 * 3. Neither the names of the above-listed copyright holders nor the names
27 * of any contributors may be used to endorse or promote products derived
28 * from this software without specific prior written permission.
29 *
30 * Alternatively, this software may be distributed under the terms of the
31 * GNU General Public License ("GPL") version 2 as published by the Free
32 * Software Foundation.
33 *
34 * NO WARRANTY
35 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
36 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
37 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
38 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
39 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
40 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
41 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
42 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
43 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
44 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
45 * THE POSSIBILITY OF SUCH DAMAGES.
46 */
47#include <linux/netdevice.h>
48#include <linux/types.h>
49#include <linux/skbuff.h>
50#include <linux/debugfs.h>
51#include <linux/random.h>
52#include <linux/ieee80211.h>
53#include <net/mac80211.h>
54#include "rate.h"
55#include "rc80211_minstrel.h"
56
57#define SAMPLE_COLUMNS 10
58#define SAMPLE_TBL(_mi, _idx, _col) \
59 _mi->sample_table[(_idx * SAMPLE_COLUMNS) + _col]
60
61/* convert mac80211 rate index to local array index */
62static inline int
63rix_to_ndx(struct minstrel_sta_info *mi, int rix)
64{
65 int i = rix;
66 for (i = rix; i >= 0; i--)
67 if (mi->r[i].rix == rix)
68 break;
69 WARN_ON(mi->r[i].rix != rix);
70 return i;
71}
72
73static inline bool
74use_low_rate(struct sk_buff *skb)
75{
76 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
77 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
78 u16 fc;
79
80 fc = le16_to_cpu(hdr->frame_control);
81
82 return ((info->flags & IEEE80211_TX_CTL_NO_ACK) ||
83 (fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA ||
84 is_multicast_ether_addr(hdr->addr1));
85}
86
87
88static void
89minstrel_update_stats(struct minstrel_priv *mp, struct minstrel_sta_info *mi)
90{
91 u32 max_tp = 0, index_max_tp = 0, index_max_tp2 = 0;
92 u32 max_prob = 0, index_max_prob = 0;
93 u32 usecs;
94 u32 p;
95 int i;
96
97 mi->stats_update = jiffies;
98 for (i = 0; i < mi->n_rates; i++) {
99 struct minstrel_rate *mr = &mi->r[i];
100
101 usecs = mr->perfect_tx_time;
102 if (!usecs)
103 usecs = 1000000;
104
105 /* To avoid rounding issues, probabilities scale from 0 (0%)
106 * to 18000 (100%) */
107 if (mr->attempts) {
108 p = (mr->success * 18000) / mr->attempts;
109 mr->succ_hist += mr->success;
110 mr->att_hist += mr->attempts;
111 mr->cur_prob = p;
112 p = ((p * (100 - mp->ewma_level)) + (mr->probability *
113 mp->ewma_level)) / 100;
114 mr->probability = p;
115 mr->cur_tp = p * (1000000 / usecs);
116 }
117
118 mr->last_success = mr->success;
119 mr->last_attempts = mr->attempts;
120 mr->success = 0;
121 mr->attempts = 0;
122
123 /* Sample less often below the 10% chance of success.
124 * Sample less often above the 95% chance of success. */
125 if ((mr->probability > 17100) || (mr->probability < 1800)) {
126 mr->adjusted_retry_count = mr->retry_count >> 1;
127 if (mr->adjusted_retry_count > 2)
128 mr->adjusted_retry_count = 2;
Felix Fietkauf4a8cd92008-10-15 19:13:59 +0200129 mr->sample_limit = 4;
Felix Fietkaucccf1292008-10-05 18:07:45 +0200130 } else {
Felix Fietkauf4a8cd92008-10-15 19:13:59 +0200131 mr->sample_limit = -1;
Felix Fietkaucccf1292008-10-05 18:07:45 +0200132 mr->adjusted_retry_count = mr->retry_count;
133 }
134 if (!mr->adjusted_retry_count)
135 mr->adjusted_retry_count = 2;
136 }
137
138 for (i = 0; i < mi->n_rates; i++) {
139 struct minstrel_rate *mr = &mi->r[i];
140 if (max_tp < mr->cur_tp) {
141 index_max_tp = i;
142 max_tp = mr->cur_tp;
143 }
144 if (max_prob < mr->probability) {
145 index_max_prob = i;
146 max_prob = mr->probability;
147 }
148 }
149
150 max_tp = 0;
151 for (i = 0; i < mi->n_rates; i++) {
152 struct minstrel_rate *mr = &mi->r[i];
153
154 if (i == index_max_tp)
155 continue;
156
157 if (max_tp < mr->cur_tp) {
158 index_max_tp2 = i;
159 max_tp = mr->cur_tp;
160 }
161 }
162 mi->max_tp_rate = index_max_tp;
163 mi->max_tp_rate2 = index_max_tp2;
164 mi->max_prob_rate = index_max_prob;
165}
166
167static void
168minstrel_tx_status(void *priv, struct ieee80211_supported_band *sband,
169 struct ieee80211_sta *sta, void *priv_sta,
170 struct sk_buff *skb)
171{
172 struct minstrel_sta_info *mi = priv_sta;
173 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
Johannes Berge6a98542008-10-21 12:40:02 +0200174 struct ieee80211_tx_rate *ar = info->status.rates;
175 int i, ndx;
176 int success;
Felix Fietkaucccf1292008-10-05 18:07:45 +0200177
Johannes Berge6a98542008-10-21 12:40:02 +0200178 success = !!(info->flags & IEEE80211_TX_STAT_ACK);
Felix Fietkaucccf1292008-10-05 18:07:45 +0200179
Johannes Berge6a98542008-10-21 12:40:02 +0200180 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
181 if (ar[i].idx < 0)
Felix Fietkaucccf1292008-10-05 18:07:45 +0200182 break;
183
Johannes Berge6a98542008-10-21 12:40:02 +0200184 ndx = rix_to_ndx(mi, ar[i].idx);
185 mi->r[ndx].attempts += ar[i].count;
Felix Fietkaucccf1292008-10-05 18:07:45 +0200186
Johannes Berge6a98542008-10-21 12:40:02 +0200187 if ((i != IEEE80211_TX_MAX_RATES - 1) && (ar[i + 1].idx < 0))
Felix Fietkaucccf1292008-10-05 18:07:45 +0200188 mi->r[ndx].success += success;
189 }
190
191 if ((info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) && (i >= 0))
192 mi->sample_count++;
193
194 if (mi->sample_deferred > 0)
195 mi->sample_deferred--;
196}
197
198
199static inline unsigned int
200minstrel_get_retry_count(struct minstrel_rate *mr,
201 struct ieee80211_tx_info *info)
202{
203 unsigned int retry = mr->adjusted_retry_count;
204
Johannes Berge6a98542008-10-21 12:40:02 +0200205 if (info->control.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS)
Felix Fietkaucccf1292008-10-05 18:07:45 +0200206 retry = max(2U, min(mr->retry_count_rtscts, retry));
Johannes Berge6a98542008-10-21 12:40:02 +0200207 else if (info->control.rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT)
Felix Fietkaucccf1292008-10-05 18:07:45 +0200208 retry = max(2U, min(mr->retry_count_cts, retry));
209 return retry;
210}
211
212
213static int
214minstrel_get_next_sample(struct minstrel_sta_info *mi)
215{
216 unsigned int sample_ndx;
217 sample_ndx = SAMPLE_TBL(mi, mi->sample_idx, mi->sample_column);
218 mi->sample_idx++;
219 if (mi->sample_idx > (mi->n_rates - 2)) {
220 mi->sample_idx = 0;
221 mi->sample_column++;
222 if (mi->sample_column >= SAMPLE_COLUMNS)
223 mi->sample_column = 0;
224 }
225 return sample_ndx;
226}
227
Johannes Berg2df78162008-10-28 16:49:41 +0100228static void
Johannes Berge6a98542008-10-21 12:40:02 +0200229minstrel_get_rate(void *priv, struct ieee80211_sta *sta,
230 void *priv_sta, struct ieee80211_tx_rate_control *txrc)
Felix Fietkaucccf1292008-10-05 18:07:45 +0200231{
Johannes Berge6a98542008-10-21 12:40:02 +0200232 struct sk_buff *skb = txrc->skb;
233 struct ieee80211_supported_band *sband = txrc->sband;
Felix Fietkaucccf1292008-10-05 18:07:45 +0200234 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
235 struct minstrel_sta_info *mi = priv_sta;
236 struct minstrel_priv *mp = priv;
Johannes Berge6a98542008-10-21 12:40:02 +0200237 struct ieee80211_tx_rate *ar = info->control.rates;
Felix Fietkaucccf1292008-10-05 18:07:45 +0200238 unsigned int ndx, sample_ndx = 0;
239 bool mrr;
240 bool sample_slower = false;
241 bool sample = false;
242 int i, delta;
243 int mrr_ndx[3];
244 int sample_rate;
245
246 if (!sta || !mi || use_low_rate(skb)) {
Johannes Berge6a98542008-10-21 12:40:02 +0200247 ar[0].idx = rate_lowest_index(sband, sta);
248 ar[0].count = mp->max_retry;
Felix Fietkaucccf1292008-10-05 18:07:45 +0200249 return;
250 }
251
Johannes Berge6a98542008-10-21 12:40:02 +0200252 mrr = mp->has_mrr && !txrc->rts && !txrc->bss_conf->use_cts_prot;
Felix Fietkaucccf1292008-10-05 18:07:45 +0200253
254 if (time_after(jiffies, mi->stats_update + (mp->update_interval *
255 HZ) / 1000))
256 minstrel_update_stats(mp, mi);
257
258 ndx = mi->max_tp_rate;
259
260 if (mrr)
261 sample_rate = mp->lookaround_rate_mrr;
262 else
263 sample_rate = mp->lookaround_rate;
264
265 mi->packet_count++;
266 delta = (mi->packet_count * sample_rate / 100) -
267 (mi->sample_count + mi->sample_deferred / 2);
268
269 /* delta > 0: sampling required */
Felix Fietkauf4a8cd92008-10-15 19:13:59 +0200270 if ((delta > 0) && (mrr || !mi->prev_sample)) {
271 struct minstrel_rate *msr;
Felix Fietkaucccf1292008-10-05 18:07:45 +0200272 if (mi->packet_count >= 10000) {
273 mi->sample_deferred = 0;
274 mi->sample_count = 0;
275 mi->packet_count = 0;
276 } else if (delta > mi->n_rates * 2) {
277 /* With multi-rate retry, not every planned sample
278 * attempt actually gets used, due to the way the retry
279 * chain is set up - [max_tp,sample,prob,lowest] for
280 * sample_rate < max_tp.
281 *
282 * If there's too much sampling backlog and the link
283 * starts getting worse, minstrel would start bursting
284 * out lots of sampling frames, which would result
285 * in a large throughput loss. */
286 mi->sample_count += (delta - mi->n_rates * 2);
287 }
288
289 sample_ndx = minstrel_get_next_sample(mi);
Felix Fietkauf4a8cd92008-10-15 19:13:59 +0200290 msr = &mi->r[sample_ndx];
Felix Fietkaucccf1292008-10-05 18:07:45 +0200291 sample = true;
Felix Fietkauf4a8cd92008-10-15 19:13:59 +0200292 sample_slower = mrr && (msr->perfect_tx_time >
Felix Fietkaucccf1292008-10-05 18:07:45 +0200293 mi->r[ndx].perfect_tx_time);
294
295 if (!sample_slower) {
Felix Fietkauf4a8cd92008-10-15 19:13:59 +0200296 if (msr->sample_limit != 0) {
297 ndx = sample_ndx;
298 mi->sample_count++;
299 if (msr->sample_limit > 0)
300 msr->sample_limit--;
301 } else {
302 sample = false;
303 }
Felix Fietkaucccf1292008-10-05 18:07:45 +0200304 } else {
305 /* Only use IEEE80211_TX_CTL_RATE_CTRL_PROBE to mark
306 * packets that have the sampling rate deferred to the
307 * second MRR stage. Increase the sample counter only
308 * if the deferred sample rate was actually used.
309 * Use the sample_deferred counter to make sure that
310 * the sampling is not done in large bursts */
311 info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE;
312 mi->sample_deferred++;
313 }
314 }
Felix Fietkauf4a8cd92008-10-15 19:13:59 +0200315 mi->prev_sample = sample;
316
317 /* If we're not using MRR and the sampling rate already
318 * has a probability of >95%, we shouldn't be attempting
319 * to use it, as this only wastes precious airtime */
320 if (!mrr && sample && (mi->r[ndx].probability > 17100))
321 ndx = mi->max_tp_rate;
322
Johannes Berge6a98542008-10-21 12:40:02 +0200323 ar[0].idx = mi->r[ndx].rix;
324 ar[0].count = minstrel_get_retry_count(&mi->r[ndx], info);
Felix Fietkaucccf1292008-10-05 18:07:45 +0200325
326 if (!mrr) {
Felix Fietkauf4a8cd92008-10-15 19:13:59 +0200327 if (!sample)
328 ar[0].count = mp->max_retry;
Johannes Berge6a98542008-10-21 12:40:02 +0200329 ar[1].idx = mi->lowest_rix;
330 ar[1].count = mp->max_retry;
Felix Fietkaucccf1292008-10-05 18:07:45 +0200331 return;
332 }
333
334 /* MRR setup */
335 if (sample) {
336 if (sample_slower)
337 mrr_ndx[0] = sample_ndx;
338 else
339 mrr_ndx[0] = mi->max_tp_rate;
340 } else {
341 mrr_ndx[0] = mi->max_tp_rate2;
342 }
343 mrr_ndx[1] = mi->max_prob_rate;
344 mrr_ndx[2] = 0;
Johannes Berge6a98542008-10-21 12:40:02 +0200345 for (i = 1; i < 4; i++) {
346 ar[i].idx = mi->r[mrr_ndx[i - 1]].rix;
347 ar[i].count = mi->r[mrr_ndx[i - 1]].adjusted_retry_count;
Felix Fietkaucccf1292008-10-05 18:07:45 +0200348 }
349}
350
351
352static void
353calc_rate_durations(struct minstrel_sta_info *mi, struct ieee80211_local *local,
354 struct minstrel_rate *d, struct ieee80211_rate *rate)
355{
356 int erp = !!(rate->flags & IEEE80211_RATE_ERP_G);
357
358 d->perfect_tx_time = ieee80211_frame_duration(local, 1200,
359 rate->bitrate, erp, 1);
360 d->ack_time = ieee80211_frame_duration(local, 10,
361 rate->bitrate, erp, 1);
362}
363
364static void
365init_sample_table(struct minstrel_sta_info *mi)
366{
367 unsigned int i, col, new_idx;
368 unsigned int n_srates = mi->n_rates - 1;
369 u8 rnd[8];
370
371 mi->sample_column = 0;
372 mi->sample_idx = 0;
373 memset(mi->sample_table, 0, SAMPLE_COLUMNS * mi->n_rates);
374
375 for (col = 0; col < SAMPLE_COLUMNS; col++) {
376 for (i = 0; i < n_srates; i++) {
377 get_random_bytes(rnd, sizeof(rnd));
378 new_idx = (i + rnd[i & 7]) % n_srates;
379
380 while (SAMPLE_TBL(mi, new_idx, col) != 0)
381 new_idx = (new_idx + 1) % n_srates;
382
383 /* Don't sample the slowest rate (i.e. slowest base
384 * rate). We must presume that the slowest rate works
385 * fine, or else other management frames will also be
386 * failing and the link will break */
387 SAMPLE_TBL(mi, new_idx, col) = i + 1;
388 }
389 }
390}
391
392static void
393minstrel_rate_init(void *priv, struct ieee80211_supported_band *sband,
394 struct ieee80211_sta *sta, void *priv_sta)
395{
396 struct minstrel_sta_info *mi = priv_sta;
397 struct minstrel_priv *mp = priv;
Christian Lamparterd57854b2008-12-22 15:35:31 +0100398 struct ieee80211_local *local = hw_to_local(mp->hw);
399 struct ieee80211_rate *ctl_rate;
Felix Fietkaucccf1292008-10-05 18:07:45 +0200400 unsigned int i, n = 0;
401 unsigned int t_slot = 9; /* FIXME: get real slot time */
402
403 mi->lowest_rix = rate_lowest_index(sband, sta);
Christian Lamparterd57854b2008-12-22 15:35:31 +0100404 ctl_rate = &sband->bitrates[mi->lowest_rix];
405 mi->sp_ack_dur = ieee80211_frame_duration(local, 10, ctl_rate->bitrate,
406 !!(ctl_rate->flags & IEEE80211_RATE_ERP_G), 1);
Felix Fietkaucccf1292008-10-05 18:07:45 +0200407
408 for (i = 0; i < sband->n_bitrates; i++) {
409 struct minstrel_rate *mr = &mi->r[n];
410 unsigned int tx_time = 0, tx_time_cts = 0, tx_time_rtscts = 0;
411 unsigned int tx_time_single;
412 unsigned int cw = mp->cw_min;
413
414 if (!rate_supported(sta, sband->band, i))
415 continue;
416 n++;
417 memset(mr, 0, sizeof(*mr));
418
419 mr->rix = i;
420 mr->bitrate = sband->bitrates[i].bitrate / 5;
Christian Lamparterd57854b2008-12-22 15:35:31 +0100421 calc_rate_durations(mi, local, mr,
Felix Fietkaucccf1292008-10-05 18:07:45 +0200422 &sband->bitrates[i]);
423
424 /* calculate maximum number of retransmissions before
425 * fallback (based on maximum segment size) */
Felix Fietkauf4a8cd92008-10-15 19:13:59 +0200426 mr->sample_limit = -1;
Felix Fietkaucccf1292008-10-05 18:07:45 +0200427 mr->retry_count = 1;
428 mr->retry_count_cts = 1;
429 mr->retry_count_rtscts = 1;
430 tx_time = mr->perfect_tx_time + mi->sp_ack_dur;
431 do {
432 /* add one retransmission */
433 tx_time_single = mr->ack_time + mr->perfect_tx_time;
434
435 /* contention window */
436 tx_time_single += t_slot + min(cw, mp->cw_max);
437 cw = (cw + 1) << 1;
438
439 tx_time += tx_time_single;
440 tx_time_cts += tx_time_single + mi->sp_ack_dur;
441 tx_time_rtscts += tx_time_single + 2 * mi->sp_ack_dur;
442 if ((tx_time_cts < mp->segment_size) &&
443 (mr->retry_count_cts < mp->max_retry))
444 mr->retry_count_cts++;
445 if ((tx_time_rtscts < mp->segment_size) &&
446 (mr->retry_count_rtscts < mp->max_retry))
447 mr->retry_count_rtscts++;
448 } while ((tx_time < mp->segment_size) &&
449 (++mr->retry_count < mp->max_retry));
450 mr->adjusted_retry_count = mr->retry_count;
451 }
452
453 for (i = n; i < sband->n_bitrates; i++) {
454 struct minstrel_rate *mr = &mi->r[i];
455 mr->rix = -1;
456 }
457
458 mi->n_rates = n;
459 mi->stats_update = jiffies;
460
461 init_sample_table(mi);
462}
463
464static void *
465minstrel_alloc_sta(void *priv, struct ieee80211_sta *sta, gfp_t gfp)
466{
467 struct ieee80211_supported_band *sband;
468 struct minstrel_sta_info *mi;
469 struct minstrel_priv *mp = priv;
470 struct ieee80211_hw *hw = mp->hw;
471 int max_rates = 0;
472 int i;
473
474 mi = kzalloc(sizeof(struct minstrel_sta_info), gfp);
475 if (!mi)
476 return NULL;
477
478 for (i = 0; i < IEEE80211_NUM_BANDS; i++) {
Jiri Slaby8e532172009-05-04 18:04:55 +0200479 sband = hw->wiphy->bands[i];
John W. Linville621ad7c2009-05-05 15:18:26 -0400480 if (sband && sband->n_bitrates > max_rates)
Felix Fietkaucccf1292008-10-05 18:07:45 +0200481 max_rates = sband->n_bitrates;
482 }
483
484 mi->r = kzalloc(sizeof(struct minstrel_rate) * max_rates, gfp);
485 if (!mi->r)
486 goto error;
487
488 mi->sample_table = kmalloc(SAMPLE_COLUMNS * max_rates, gfp);
489 if (!mi->sample_table)
490 goto error1;
491
492 mi->stats_update = jiffies;
493 return mi;
494
495error1:
496 kfree(mi->r);
497error:
498 kfree(mi);
499 return NULL;
500}
501
502static void
503minstrel_free_sta(void *priv, struct ieee80211_sta *sta, void *priv_sta)
504{
505 struct minstrel_sta_info *mi = priv_sta;
506
507 kfree(mi->sample_table);
508 kfree(mi->r);
509 kfree(mi);
510}
511
Felix Fietkaucccf1292008-10-05 18:07:45 +0200512static void *
513minstrel_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
514{
515 struct minstrel_priv *mp;
516
517 mp = kzalloc(sizeof(struct minstrel_priv), GFP_ATOMIC);
518 if (!mp)
519 return NULL;
520
521 /* contention window settings
522 * Just an approximation. Using the per-queue values would complicate
523 * the calculations and is probably unnecessary */
524 mp->cw_min = 15;
525 mp->cw_max = 1023;
526
527 /* number of packets (in %) to use for sampling other rates
528 * sample less often for non-mrr packets, because the overhead
529 * is much higher than with mrr */
530 mp->lookaround_rate = 5;
531 mp->lookaround_rate_mrr = 10;
532
533 /* moving average weight for EWMA */
534 mp->ewma_level = 75;
535
536 /* maximum time that the hw is allowed to stay in one MRR segment */
537 mp->segment_size = 6000;
538
Johannes Berge6a98542008-10-21 12:40:02 +0200539 if (hw->max_rate_tries > 0)
540 mp->max_retry = hw->max_rate_tries;
Felix Fietkaucccf1292008-10-05 18:07:45 +0200541 else
542 /* safe default, does not necessarily have to match hw properties */
543 mp->max_retry = 7;
544
Johannes Berge6a98542008-10-21 12:40:02 +0200545 if (hw->max_rates >= 4)
Felix Fietkaucccf1292008-10-05 18:07:45 +0200546 mp->has_mrr = true;
547
548 mp->hw = hw;
549 mp->update_interval = 100;
550
551 return mp;
552}
553
554static void
555minstrel_free(void *priv)
556{
557 kfree(priv);
558}
559
560static struct rate_control_ops mac80211_minstrel = {
561 .name = "minstrel",
562 .tx_status = minstrel_tx_status,
563 .get_rate = minstrel_get_rate,
564 .rate_init = minstrel_rate_init,
Felix Fietkaucccf1292008-10-05 18:07:45 +0200565 .alloc = minstrel_alloc,
566 .free = minstrel_free,
567 .alloc_sta = minstrel_alloc_sta,
568 .free_sta = minstrel_free_sta,
569#ifdef CONFIG_MAC80211_DEBUGFS
570 .add_sta_debugfs = minstrel_add_sta_debugfs,
571 .remove_sta_debugfs = minstrel_remove_sta_debugfs,
572#endif
573};
574
575int __init
576rc80211_minstrel_init(void)
577{
578 return ieee80211_rate_control_register(&mac80211_minstrel);
579}
580
581void
582rc80211_minstrel_exit(void)
583{
584 ieee80211_rate_control_unregister(&mac80211_minstrel);
585}
586