1 // SPDX-License-Identifier: GPL-2.0-only
2 /******************************************************************************
3 *
4 * Copyright(c) 2008 - 2014 Intel Corporation. All rights reserved.
5 * Copyright(c) 2018 Intel Corporation
6 *****************************************************************************/
7 #include <linux/slab.h>
8 #include <linux/types.h>
9 #include <linux/etherdevice.h>
10 #include <net/mac80211.h>
11
12 #include "dev.h"
13 #include "agn.h"
14
15 /* For active scan, listen ACTIVE_DWELL_TIME (msec) on each channel after
16 * sending probe req. This should be set long enough to hear probe responses
17 * from more than one AP. */
18 #define IWL_ACTIVE_DWELL_TIME_24 (30) /* all times in msec */
19 #define IWL_ACTIVE_DWELL_TIME_52 (20)
20
21 #define IWL_ACTIVE_DWELL_FACTOR_24GHZ (3)
22 #define IWL_ACTIVE_DWELL_FACTOR_52GHZ (2)
23
24 /* For passive scan, listen PASSIVE_DWELL_TIME (msec) on each channel.
25 * Must be set longer than active dwell time.
26 * For the most reliable scan, set > AP beacon interval (typically 100msec). */
27 #define IWL_PASSIVE_DWELL_TIME_24 (20) /* all times in msec */
28 #define IWL_PASSIVE_DWELL_TIME_52 (10)
29 #define IWL_PASSIVE_DWELL_BASE (100)
30 #define IWL_CHANNEL_TUNE_TIME 5
31 #define MAX_SCAN_CHANNEL 50
32
33 /* For reset radio, need minimal dwell time only */
34 #define IWL_RADIO_RESET_DWELL_TIME 5
35
iwl_send_scan_abort(struct iwl_priv * priv)36 static int iwl_send_scan_abort(struct iwl_priv *priv)
37 {
38 int ret;
39 struct iwl_host_cmd cmd = {
40 .id = REPLY_SCAN_ABORT_CMD,
41 .flags = CMD_WANT_SKB,
42 };
43 __le32 *status;
44
45 /* Exit instantly with error when device is not ready
46 * to receive scan abort command or it does not perform
47 * hardware scan currently */
48 if (!test_bit(STATUS_READY, &priv->status) ||
49 !test_bit(STATUS_SCAN_HW, &priv->status) ||
50 test_bit(STATUS_FW_ERROR, &priv->status))
51 return -EIO;
52
53 ret = iwl_dvm_send_cmd(priv, &cmd);
54 if (ret)
55 return ret;
56
57 status = (void *)cmd.resp_pkt->data;
58 if (*status != CAN_ABORT_STATUS) {
59 /* The scan abort will return 1 for success or
60 * 2 for "failure". A failure condition can be
61 * due to simply not being in an active scan which
62 * can occur if we send the scan abort before we
63 * the microcode has notified us that a scan is
64 * completed. */
65 IWL_DEBUG_SCAN(priv, "SCAN_ABORT ret %d.\n",
66 le32_to_cpu(*status));
67 ret = -EIO;
68 }
69
70 iwl_free_resp(&cmd);
71 return ret;
72 }
73
iwl_complete_scan(struct iwl_priv * priv,bool aborted)74 static void iwl_complete_scan(struct iwl_priv *priv, bool aborted)
75 {
76 struct cfg80211_scan_info info = {
77 .aborted = aborted,
78 };
79
80 /* check if scan was requested from mac80211 */
81 if (priv->scan_request) {
82 IWL_DEBUG_SCAN(priv, "Complete scan in mac80211\n");
83 ieee80211_scan_completed(priv->hw, &info);
84 }
85
86 priv->scan_type = IWL_SCAN_NORMAL;
87 priv->scan_vif = NULL;
88 priv->scan_request = NULL;
89 }
90
iwl_process_scan_complete(struct iwl_priv * priv)91 static void iwl_process_scan_complete(struct iwl_priv *priv)
92 {
93 bool aborted;
94
95 lockdep_assert_held(&priv->mutex);
96
97 if (!test_and_clear_bit(STATUS_SCAN_COMPLETE, &priv->status))
98 return;
99
100 IWL_DEBUG_SCAN(priv, "Completed scan.\n");
101
102 cancel_delayed_work(&priv->scan_check);
103
104 aborted = test_and_clear_bit(STATUS_SCAN_ABORTING, &priv->status);
105 if (aborted)
106 IWL_DEBUG_SCAN(priv, "Aborted scan completed.\n");
107
108 if (!test_and_clear_bit(STATUS_SCANNING, &priv->status)) {
109 IWL_DEBUG_SCAN(priv, "Scan already completed.\n");
110 goto out_settings;
111 }
112
113 if (priv->scan_type != IWL_SCAN_NORMAL && !aborted) {
114 int err;
115
116 /* Check if mac80211 requested scan during our internal scan */
117 if (priv->scan_request == NULL)
118 goto out_complete;
119
120 /* If so request a new scan */
121 err = iwl_scan_initiate(priv, priv->scan_vif, IWL_SCAN_NORMAL,
122 priv->scan_request->channels[0]->band);
123 if (err) {
124 IWL_DEBUG_SCAN(priv,
125 "failed to initiate pending scan: %d\n", err);
126 aborted = true;
127 goto out_complete;
128 }
129
130 return;
131 }
132
133 out_complete:
134 iwl_complete_scan(priv, aborted);
135
136 out_settings:
137 /* Can we still talk to firmware ? */
138 if (!iwl_is_ready_rf(priv))
139 return;
140
141 iwlagn_post_scan(priv);
142 }
143
iwl_force_scan_end(struct iwl_priv * priv)144 void iwl_force_scan_end(struct iwl_priv *priv)
145 {
146 lockdep_assert_held(&priv->mutex);
147
148 if (!test_bit(STATUS_SCANNING, &priv->status)) {
149 IWL_DEBUG_SCAN(priv, "Forcing scan end while not scanning\n");
150 return;
151 }
152
153 IWL_DEBUG_SCAN(priv, "Forcing scan end\n");
154 clear_bit(STATUS_SCANNING, &priv->status);
155 clear_bit(STATUS_SCAN_HW, &priv->status);
156 clear_bit(STATUS_SCAN_ABORTING, &priv->status);
157 clear_bit(STATUS_SCAN_COMPLETE, &priv->status);
158 iwl_complete_scan(priv, true);
159 }
160
iwl_do_scan_abort(struct iwl_priv * priv)161 static void iwl_do_scan_abort(struct iwl_priv *priv)
162 {
163 int ret;
164
165 lockdep_assert_held(&priv->mutex);
166
167 if (!test_bit(STATUS_SCANNING, &priv->status)) {
168 IWL_DEBUG_SCAN(priv, "Not performing scan to abort\n");
169 return;
170 }
171
172 if (test_and_set_bit(STATUS_SCAN_ABORTING, &priv->status)) {
173 IWL_DEBUG_SCAN(priv, "Scan abort in progress\n");
174 return;
175 }
176
177 ret = iwl_send_scan_abort(priv);
178 if (ret) {
179 IWL_DEBUG_SCAN(priv, "Send scan abort failed %d\n", ret);
180 iwl_force_scan_end(priv);
181 } else
182 IWL_DEBUG_SCAN(priv, "Successfully send scan abort\n");
183 }
184
185 /*
186 * iwl_scan_cancel - Cancel any currently executing HW scan
187 */
iwl_scan_cancel(struct iwl_priv * priv)188 int iwl_scan_cancel(struct iwl_priv *priv)
189 {
190 IWL_DEBUG_SCAN(priv, "Queuing abort scan\n");
191 queue_work(priv->workqueue, &priv->abort_scan);
192 return 0;
193 }
194
195 /*
196 * iwl_scan_cancel_timeout - Cancel any currently executing HW scan
197 * @ms: amount of time to wait (in milliseconds) for scan to abort
198 */
iwl_scan_cancel_timeout(struct iwl_priv * priv,unsigned long ms)199 void iwl_scan_cancel_timeout(struct iwl_priv *priv, unsigned long ms)
200 {
201 unsigned long timeout = jiffies + msecs_to_jiffies(ms);
202
203 lockdep_assert_held(&priv->mutex);
204
205 IWL_DEBUG_SCAN(priv, "Scan cancel timeout\n");
206
207 iwl_do_scan_abort(priv);
208
209 while (time_before_eq(jiffies, timeout)) {
210 if (!test_bit(STATUS_SCAN_HW, &priv->status))
211 goto finished;
212 msleep(20);
213 }
214
215 return;
216
217 finished:
218 /*
219 * Now STATUS_SCAN_HW is clear. This means that the
220 * device finished, but the background work is going
221 * to execute at best as soon as we release the mutex.
222 * Since we need to be able to issue a new scan right
223 * after this function returns, run the complete here.
224 * The STATUS_SCAN_COMPLETE bit will then be cleared
225 * and prevent the background work from "completing"
226 * a possible new scan.
227 */
228 iwl_process_scan_complete(priv);
229 }
230
231 /* Service response to REPLY_SCAN_CMD (0x80) */
iwl_rx_reply_scan(struct iwl_priv * priv,struct iwl_rx_cmd_buffer * rxb)232 static void iwl_rx_reply_scan(struct iwl_priv *priv,
233 struct iwl_rx_cmd_buffer *rxb)
234 {
235 #ifdef CONFIG_IWLWIFI_DEBUG
236 struct iwl_rx_packet *pkt = rxb_addr(rxb);
237 struct iwl_scanreq_notification *notif = (void *)pkt->data;
238
239 IWL_DEBUG_SCAN(priv, "Scan request status = 0x%x\n", notif->status);
240 #endif
241 }
242
243 /* Service SCAN_START_NOTIFICATION (0x82) */
iwl_rx_scan_start_notif(struct iwl_priv * priv,struct iwl_rx_cmd_buffer * rxb)244 static void iwl_rx_scan_start_notif(struct iwl_priv *priv,
245 struct iwl_rx_cmd_buffer *rxb)
246 {
247 struct iwl_rx_packet *pkt = rxb_addr(rxb);
248 struct iwl_scanstart_notification *notif = (void *)pkt->data;
249
250 priv->scan_start_tsf = le32_to_cpu(notif->tsf_low);
251 IWL_DEBUG_SCAN(priv, "Scan start: "
252 "%d [802.11%s] "
253 "(TSF: 0x%08X:%08X) - %d (beacon timer %u)\n",
254 notif->channel,
255 notif->band ? "bg" : "a",
256 le32_to_cpu(notif->tsf_high),
257 le32_to_cpu(notif->tsf_low),
258 notif->status, notif->beacon_timer);
259 }
260
261 /* Service SCAN_RESULTS_NOTIFICATION (0x83) */
iwl_rx_scan_results_notif(struct iwl_priv * priv,struct iwl_rx_cmd_buffer * rxb)262 static void iwl_rx_scan_results_notif(struct iwl_priv *priv,
263 struct iwl_rx_cmd_buffer *rxb)
264 {
265 #ifdef CONFIG_IWLWIFI_DEBUG
266 struct iwl_rx_packet *pkt = rxb_addr(rxb);
267 struct iwl_scanresults_notification *notif = (void *)pkt->data;
268
269 IWL_DEBUG_SCAN(priv, "Scan ch.res: "
270 "%d [802.11%s] "
271 "probe status: %u:%u "
272 "(TSF: 0x%08X:%08X) - %d "
273 "elapsed=%lu usec\n",
274 notif->channel,
275 notif->band ? "bg" : "a",
276 notif->probe_status, notif->num_probe_not_sent,
277 le32_to_cpu(notif->tsf_high),
278 le32_to_cpu(notif->tsf_low),
279 le32_to_cpu(notif->statistics[0]),
280 le32_to_cpu(notif->tsf_low) - priv->scan_start_tsf);
281 #endif
282 }
283
284 /* Service SCAN_COMPLETE_NOTIFICATION (0x84) */
iwl_rx_scan_complete_notif(struct iwl_priv * priv,struct iwl_rx_cmd_buffer * rxb)285 static void iwl_rx_scan_complete_notif(struct iwl_priv *priv,
286 struct iwl_rx_cmd_buffer *rxb)
287 {
288 struct iwl_rx_packet *pkt = rxb_addr(rxb);
289 struct iwl_scancomplete_notification *scan_notif = (void *)pkt->data;
290
291 IWL_DEBUG_SCAN(priv, "Scan complete: %d channels (TSF 0x%08X:%08X) - %d\n",
292 scan_notif->scanned_channels,
293 scan_notif->tsf_low,
294 scan_notif->tsf_high, scan_notif->status);
295
296 IWL_DEBUG_SCAN(priv, "Scan on %sGHz took %dms\n",
297 (priv->scan_band == NL80211_BAND_2GHZ) ? "2.4" : "5.2",
298 jiffies_to_msecs(jiffies - priv->scan_start));
299
300 /*
301 * When aborting, we run the scan completed background work inline
302 * and the background work must then do nothing. The SCAN_COMPLETE
303 * bit helps implement that logic and thus needs to be set before
304 * queueing the work. Also, since the scan abort waits for SCAN_HW
305 * to clear, we need to set SCAN_COMPLETE before clearing SCAN_HW
306 * to avoid a race there.
307 */
308 set_bit(STATUS_SCAN_COMPLETE, &priv->status);
309 clear_bit(STATUS_SCAN_HW, &priv->status);
310 queue_work(priv->workqueue, &priv->scan_completed);
311
312 if (priv->iw_mode != NL80211_IFTYPE_ADHOC &&
313 iwl_advanced_bt_coexist(priv) &&
314 priv->bt_status != scan_notif->bt_status) {
315 if (scan_notif->bt_status) {
316 /* BT on */
317 if (!priv->bt_ch_announce)
318 priv->bt_traffic_load =
319 IWL_BT_COEX_TRAFFIC_LOAD_HIGH;
320 /*
321 * otherwise, no traffic load information provided
322 * no changes made
323 */
324 } else {
325 /* BT off */
326 priv->bt_traffic_load =
327 IWL_BT_COEX_TRAFFIC_LOAD_NONE;
328 }
329 priv->bt_status = scan_notif->bt_status;
330 queue_work(priv->workqueue,
331 &priv->bt_traffic_change_work);
332 }
333 }
334
iwl_setup_rx_scan_handlers(struct iwl_priv * priv)335 void iwl_setup_rx_scan_handlers(struct iwl_priv *priv)
336 {
337 /* scan handlers */
338 priv->rx_handlers[REPLY_SCAN_CMD] = iwl_rx_reply_scan;
339 priv->rx_handlers[SCAN_START_NOTIFICATION] = iwl_rx_scan_start_notif;
340 priv->rx_handlers[SCAN_RESULTS_NOTIFICATION] =
341 iwl_rx_scan_results_notif;
342 priv->rx_handlers[SCAN_COMPLETE_NOTIFICATION] =
343 iwl_rx_scan_complete_notif;
344 }
345
iwl_get_active_dwell_time(struct iwl_priv * priv,enum nl80211_band band,u8 n_probes)346 static u16 iwl_get_active_dwell_time(struct iwl_priv *priv,
347 enum nl80211_band band, u8 n_probes)
348 {
349 if (band == NL80211_BAND_5GHZ)
350 return IWL_ACTIVE_DWELL_TIME_52 +
351 IWL_ACTIVE_DWELL_FACTOR_52GHZ * (n_probes + 1);
352 else
353 return IWL_ACTIVE_DWELL_TIME_24 +
354 IWL_ACTIVE_DWELL_FACTOR_24GHZ * (n_probes + 1);
355 }
356
iwl_limit_dwell(struct iwl_priv * priv,u16 dwell_time)357 static u16 iwl_limit_dwell(struct iwl_priv *priv, u16 dwell_time)
358 {
359 struct iwl_rxon_context *ctx;
360 int limits[NUM_IWL_RXON_CTX] = {};
361 int n_active = 0;
362 u16 limit;
363
364 BUILD_BUG_ON(NUM_IWL_RXON_CTX != 2);
365
366 /*
367 * If we're associated, we clamp the dwell time 98%
368 * of the beacon interval (minus 2 * channel tune time)
369 * If both contexts are active, we have to restrict to
370 * 1/2 of the minimum of them, because they might be in
371 * lock-step with the time inbetween only half of what
372 * time we'd have in each of them.
373 */
374 for_each_context(priv, ctx) {
375 switch (ctx->staging.dev_type) {
376 case RXON_DEV_TYPE_P2P:
377 /* no timing constraints */
378 continue;
379 case RXON_DEV_TYPE_ESS:
380 default:
381 /* timing constraints if associated */
382 if (!iwl_is_associated_ctx(ctx))
383 continue;
384 break;
385 case RXON_DEV_TYPE_CP:
386 case RXON_DEV_TYPE_2STA:
387 /*
388 * These seem to always have timers for TBTT
389 * active in uCode even when not associated yet.
390 */
391 break;
392 }
393
394 limits[n_active++] = ctx->beacon_int ?: IWL_PASSIVE_DWELL_BASE;
395 }
396
397 switch (n_active) {
398 case 0:
399 return dwell_time;
400 case 2:
401 limit = (limits[1] * 98) / 100 - IWL_CHANNEL_TUNE_TIME * 2;
402 limit /= 2;
403 dwell_time = min(limit, dwell_time);
404 fallthrough;
405 case 1:
406 limit = (limits[0] * 98) / 100 - IWL_CHANNEL_TUNE_TIME * 2;
407 limit /= n_active;
408 return min(limit, dwell_time);
409 default:
410 WARN_ON_ONCE(1);
411 return dwell_time;
412 }
413 }
414
iwl_get_passive_dwell_time(struct iwl_priv * priv,enum nl80211_band band)415 static u16 iwl_get_passive_dwell_time(struct iwl_priv *priv,
416 enum nl80211_band band)
417 {
418 u16 passive = (band == NL80211_BAND_2GHZ) ?
419 IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_24 :
420 IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_52;
421
422 return iwl_limit_dwell(priv, passive);
423 }
424
425 /* Return valid, unused, channel for a passive scan to reset the RF */
iwl_get_single_channel_number(struct iwl_priv * priv,enum nl80211_band band)426 static u8 iwl_get_single_channel_number(struct iwl_priv *priv,
427 enum nl80211_band band)
428 {
429 struct ieee80211_supported_band *sband = priv->hw->wiphy->bands[band];
430 struct iwl_rxon_context *ctx;
431 int i;
432
433 for (i = 0; i < sband->n_channels; i++) {
434 bool busy = false;
435
436 for_each_context(priv, ctx) {
437 busy = sband->channels[i].hw_value ==
438 le16_to_cpu(ctx->staging.channel);
439 if (busy)
440 break;
441 }
442
443 if (busy)
444 continue;
445
446 if (!(sband->channels[i].flags & IEEE80211_CHAN_DISABLED))
447 return sband->channels[i].hw_value;
448 }
449
450 return 0;
451 }
452
iwl_get_channel_for_reset_scan(struct iwl_priv * priv,struct ieee80211_vif * vif,enum nl80211_band band,struct iwl_scan_channel * scan_ch)453 static int iwl_get_channel_for_reset_scan(struct iwl_priv *priv,
454 struct ieee80211_vif *vif,
455 enum nl80211_band band,
456 struct iwl_scan_channel *scan_ch)
457 {
458 const struct ieee80211_supported_band *sband;
459 u16 channel;
460
461 sband = iwl_get_hw_mode(priv, band);
462 if (!sband) {
463 IWL_ERR(priv, "invalid band\n");
464 return 0;
465 }
466
467 channel = iwl_get_single_channel_number(priv, band);
468 if (channel) {
469 scan_ch->channel = cpu_to_le16(channel);
470 scan_ch->type = SCAN_CHANNEL_TYPE_PASSIVE;
471 scan_ch->active_dwell =
472 cpu_to_le16(IWL_RADIO_RESET_DWELL_TIME);
473 scan_ch->passive_dwell =
474 cpu_to_le16(IWL_RADIO_RESET_DWELL_TIME);
475 /* Set txpower levels to defaults */
476 scan_ch->dsp_atten = 110;
477 if (band == NL80211_BAND_5GHZ)
478 scan_ch->tx_gain = ((1 << 5) | (3 << 3)) | 3;
479 else
480 scan_ch->tx_gain = ((1 << 5) | (5 << 3));
481 return 1;
482 }
483
484 IWL_ERR(priv, "no valid channel found\n");
485 return 0;
486 }
487
iwl_get_channels_for_scan(struct iwl_priv * priv,struct ieee80211_vif * vif,enum nl80211_band band,u8 is_active,u8 n_probes,struct iwl_scan_channel * scan_ch)488 static int iwl_get_channels_for_scan(struct iwl_priv *priv,
489 struct ieee80211_vif *vif,
490 enum nl80211_band band,
491 u8 is_active, u8 n_probes,
492 struct iwl_scan_channel *scan_ch)
493 {
494 struct ieee80211_channel *chan;
495 const struct ieee80211_supported_band *sband;
496 u16 passive_dwell = 0;
497 u16 active_dwell = 0;
498 int added, i;
499 u16 channel;
500
501 sband = iwl_get_hw_mode(priv, band);
502 if (!sband)
503 return 0;
504
505 active_dwell = iwl_get_active_dwell_time(priv, band, n_probes);
506 passive_dwell = iwl_get_passive_dwell_time(priv, band);
507
508 if (passive_dwell <= active_dwell)
509 passive_dwell = active_dwell + 1;
510
511 for (i = 0, added = 0; i < priv->scan_request->n_channels; i++) {
512 chan = priv->scan_request->channels[i];
513
514 if (chan->band != band)
515 continue;
516
517 channel = chan->hw_value;
518 scan_ch->channel = cpu_to_le16(channel);
519
520 if (!is_active || (chan->flags & IEEE80211_CHAN_NO_IR))
521 scan_ch->type = SCAN_CHANNEL_TYPE_PASSIVE;
522 else
523 scan_ch->type = SCAN_CHANNEL_TYPE_ACTIVE;
524
525 if (n_probes)
526 scan_ch->type |= IWL_SCAN_PROBE_MASK(n_probes);
527
528 scan_ch->active_dwell = cpu_to_le16(active_dwell);
529 scan_ch->passive_dwell = cpu_to_le16(passive_dwell);
530
531 /* Set txpower levels to defaults */
532 scan_ch->dsp_atten = 110;
533
534 /* NOTE: if we were doing 6Mb OFDM for scans we'd use
535 * power level:
536 * scan_ch->tx_gain = ((1 << 5) | (2 << 3)) | 3;
537 */
538 if (band == NL80211_BAND_5GHZ)
539 scan_ch->tx_gain = ((1 << 5) | (3 << 3)) | 3;
540 else
541 scan_ch->tx_gain = ((1 << 5) | (5 << 3));
542
543 IWL_DEBUG_SCAN(priv, "Scanning ch=%d prob=0x%X [%s %d]\n",
544 channel, le32_to_cpu(scan_ch->type),
545 (scan_ch->type & SCAN_CHANNEL_TYPE_ACTIVE) ?
546 "ACTIVE" : "PASSIVE",
547 (scan_ch->type & SCAN_CHANNEL_TYPE_ACTIVE) ?
548 active_dwell : passive_dwell);
549
550 scan_ch++;
551 added++;
552 }
553
554 IWL_DEBUG_SCAN(priv, "total channels to scan %d\n", added);
555 return added;
556 }
557
558 /*
559 * iwl_fill_probe_req - fill in all required fields and IE for probe request
560 */
iwl_fill_probe_req(struct ieee80211_mgmt * frame,const u8 * ta,const u8 * ies,int ie_len,const u8 * ssid,u8 ssid_len,int left)561 static u16 iwl_fill_probe_req(struct ieee80211_mgmt *frame, const u8 *ta,
562 const u8 *ies, int ie_len, const u8 *ssid,
563 u8 ssid_len, int left)
564 {
565 int len = 0;
566 u8 *pos = NULL;
567
568 /* Make sure there is enough space for the probe request,
569 * two mandatory IEs and the data */
570 left -= 24;
571 if (left < 0)
572 return 0;
573
574 frame->frame_control = cpu_to_le16(IEEE80211_STYPE_PROBE_REQ);
575 eth_broadcast_addr(frame->da);
576 memcpy(frame->sa, ta, ETH_ALEN);
577 eth_broadcast_addr(frame->bssid);
578 frame->seq_ctrl = 0;
579
580 len += 24;
581
582 /* ...next IE... */
583 pos = &frame->u.probe_req.variable[0];
584
585 /* fill in our SSID IE */
586 left -= ssid_len + 2;
587 if (left < 0)
588 return 0;
589 *pos++ = WLAN_EID_SSID;
590 *pos++ = ssid_len;
591 if (ssid && ssid_len) {
592 memcpy(pos, ssid, ssid_len);
593 pos += ssid_len;
594 }
595
596 len += ssid_len + 2;
597
598 if (WARN_ON(left < ie_len))
599 return len;
600
601 if (ies && ie_len) {
602 memcpy(pos, ies, ie_len);
603 len += ie_len;
604 }
605
606 return (u16)len;
607 }
608
iwlagn_request_scan(struct iwl_priv * priv,struct ieee80211_vif * vif)609 static int iwlagn_request_scan(struct iwl_priv *priv, struct ieee80211_vif *vif)
610 {
611 struct iwl_host_cmd cmd = {
612 .id = REPLY_SCAN_CMD,
613 .len = { sizeof(struct iwl_scan_cmd), },
614 };
615 struct iwl_scan_cmd *scan;
616 struct iwl_rxon_context *ctx = &priv->contexts[IWL_RXON_CTX_BSS];
617 u32 rate_flags = 0;
618 u16 cmd_len = 0;
619 u16 rx_chain = 0;
620 enum nl80211_band band;
621 u8 n_probes = 0;
622 u8 rx_ant = priv->nvm_data->valid_rx_ant;
623 u8 rate;
624 bool is_active = false;
625 int chan_mod;
626 u8 active_chains;
627 u8 scan_tx_antennas = priv->nvm_data->valid_tx_ant;
628 int ret;
629 int scan_cmd_size = sizeof(struct iwl_scan_cmd) +
630 MAX_SCAN_CHANNEL * sizeof(struct iwl_scan_channel) +
631 priv->fw->ucode_capa.max_probe_length;
632 const u8 *ssid = NULL;
633 u8 ssid_len = 0;
634
635 if (WARN_ON(priv->scan_type == IWL_SCAN_NORMAL &&
636 (!priv->scan_request ||
637 priv->scan_request->n_channels > MAX_SCAN_CHANNEL)))
638 return -EINVAL;
639
640 lockdep_assert_held(&priv->mutex);
641
642 if (vif)
643 ctx = iwl_rxon_ctx_from_vif(vif);
644
645 if (!priv->scan_cmd) {
646 priv->scan_cmd = kmalloc(scan_cmd_size, GFP_KERNEL);
647 if (!priv->scan_cmd) {
648 IWL_DEBUG_SCAN(priv,
649 "fail to allocate memory for scan\n");
650 return -ENOMEM;
651 }
652 }
653 scan = priv->scan_cmd;
654 memset(scan, 0, scan_cmd_size);
655
656 scan->quiet_plcp_th = IWL_PLCP_QUIET_THRESH;
657 scan->quiet_time = IWL_ACTIVE_QUIET_TIME;
658
659 if (iwl_is_any_associated(priv)) {
660 u16 interval = 0;
661 u32 extra;
662 u32 suspend_time = 100;
663 u32 scan_suspend_time = 100;
664
665 IWL_DEBUG_INFO(priv, "Scanning while associated...\n");
666 switch (priv->scan_type) {
667 case IWL_SCAN_RADIO_RESET:
668 interval = 0;
669 break;
670 case IWL_SCAN_NORMAL:
671 interval = vif->bss_conf.beacon_int;
672 break;
673 }
674
675 scan->suspend_time = 0;
676 scan->max_out_time = cpu_to_le32(200 * 1024);
677 if (!interval)
678 interval = suspend_time;
679
680 extra = (suspend_time / interval) << 22;
681 scan_suspend_time = (extra |
682 ((suspend_time % interval) * 1024));
683 scan->suspend_time = cpu_to_le32(scan_suspend_time);
684 IWL_DEBUG_SCAN(priv, "suspend_time 0x%X beacon interval %d\n",
685 scan_suspend_time, interval);
686 }
687
688 switch (priv->scan_type) {
689 case IWL_SCAN_RADIO_RESET:
690 IWL_DEBUG_SCAN(priv, "Start internal passive scan.\n");
691 /*
692 * Override quiet time as firmware checks that active
693 * dwell is >= quiet; since we use passive scan it'll
694 * not actually be used.
695 */
696 scan->quiet_time = cpu_to_le16(IWL_RADIO_RESET_DWELL_TIME);
697 break;
698 case IWL_SCAN_NORMAL:
699 if (priv->scan_request->n_ssids) {
700 int i, p = 0;
701 IWL_DEBUG_SCAN(priv, "Kicking off active scan\n");
702 /*
703 * The highest priority SSID is inserted to the
704 * probe request template.
705 */
706 ssid_len = priv->scan_request->ssids[0].ssid_len;
707 ssid = priv->scan_request->ssids[0].ssid;
708
709 /*
710 * Invert the order of ssids, the firmware will invert
711 * it back.
712 */
713 for (i = priv->scan_request->n_ssids - 1; i >= 1; i--) {
714 scan->direct_scan[p].id = WLAN_EID_SSID;
715 scan->direct_scan[p].len =
716 priv->scan_request->ssids[i].ssid_len;
717 memcpy(scan->direct_scan[p].ssid,
718 priv->scan_request->ssids[i].ssid,
719 priv->scan_request->ssids[i].ssid_len);
720 n_probes++;
721 p++;
722 }
723 is_active = true;
724 } else
725 IWL_DEBUG_SCAN(priv, "Start passive scan.\n");
726 break;
727 }
728
729 scan->tx_cmd.tx_flags = TX_CMD_FLG_SEQ_CTL_MSK;
730 scan->tx_cmd.sta_id = ctx->bcast_sta_id;
731 scan->tx_cmd.stop_time.life_time = TX_CMD_LIFE_TIME_INFINITE;
732
733 switch (priv->scan_band) {
734 case NL80211_BAND_2GHZ:
735 scan->flags = RXON_FLG_BAND_24G_MSK | RXON_FLG_AUTO_DETECT_MSK;
736 chan_mod = le32_to_cpu(
737 priv->contexts[IWL_RXON_CTX_BSS].active.flags &
738 RXON_FLG_CHANNEL_MODE_MSK)
739 >> RXON_FLG_CHANNEL_MODE_POS;
740 if ((priv->scan_request && priv->scan_request->no_cck) ||
741 chan_mod == CHANNEL_MODE_PURE_40) {
742 rate = IWL_RATE_6M_PLCP;
743 } else {
744 rate = IWL_RATE_1M_PLCP;
745 rate_flags = RATE_MCS_CCK_MSK;
746 }
747 /*
748 * Internal scans are passive, so we can indiscriminately set
749 * the BT ignore flag on 2.4 GHz since it applies to TX only.
750 */
751 if (priv->lib->bt_params &&
752 priv->lib->bt_params->advanced_bt_coexist)
753 scan->tx_cmd.tx_flags |= TX_CMD_FLG_IGNORE_BT;
754 break;
755 case NL80211_BAND_5GHZ:
756 rate = IWL_RATE_6M_PLCP;
757 break;
758 default:
759 IWL_WARN(priv, "Invalid scan band\n");
760 return -EIO;
761 }
762
763 /*
764 * If active scanning is requested but a certain channel is
765 * marked passive, we can do active scanning if we detect
766 * transmissions.
767 *
768 * There is an issue with some firmware versions that triggers
769 * a sysassert on a "good CRC threshold" of zero (== disabled),
770 * on a radar channel even though this means that we should NOT
771 * send probes.
772 *
773 * The "good CRC threshold" is the number of frames that we
774 * need to receive during our dwell time on a channel before
775 * sending out probes -- setting this to a huge value will
776 * mean we never reach it, but at the same time work around
777 * the aforementioned issue. Thus use IWL_GOOD_CRC_TH_NEVER
778 * here instead of IWL_GOOD_CRC_TH_DISABLED.
779 *
780 * This was fixed in later versions along with some other
781 * scan changes, and the threshold behaves as a flag in those
782 * versions.
783 */
784 if (priv->new_scan_threshold_behaviour)
785 scan->good_CRC_th = is_active ? IWL_GOOD_CRC_TH_DEFAULT :
786 IWL_GOOD_CRC_TH_DISABLED;
787 else
788 scan->good_CRC_th = is_active ? IWL_GOOD_CRC_TH_DEFAULT :
789 IWL_GOOD_CRC_TH_NEVER;
790
791 band = priv->scan_band;
792
793 if (band == NL80211_BAND_2GHZ &&
794 priv->lib->bt_params &&
795 priv->lib->bt_params->advanced_bt_coexist) {
796 /* transmit 2.4 GHz probes only on first antenna */
797 scan_tx_antennas = first_antenna(scan_tx_antennas);
798 }
799
800 priv->scan_tx_ant[band] = iwl_toggle_tx_ant(priv,
801 priv->scan_tx_ant[band],
802 scan_tx_antennas);
803 rate_flags |= iwl_ant_idx_to_flags(priv->scan_tx_ant[band]);
804 scan->tx_cmd.rate_n_flags = iwl_hw_set_rate_n_flags(rate, rate_flags);
805
806 /*
807 * In power save mode while associated use one chain,
808 * otherwise use all chains
809 */
810 if (test_bit(STATUS_POWER_PMI, &priv->status) &&
811 !(priv->hw->conf.flags & IEEE80211_CONF_IDLE)) {
812 /* rx_ant has been set to all valid chains previously */
813 active_chains = rx_ant &
814 ((u8)(priv->chain_noise_data.active_chains));
815 if (!active_chains)
816 active_chains = rx_ant;
817
818 IWL_DEBUG_SCAN(priv, "chain_noise_data.active_chains: %u\n",
819 priv->chain_noise_data.active_chains);
820
821 rx_ant = first_antenna(active_chains);
822 }
823 if (priv->lib->bt_params &&
824 priv->lib->bt_params->advanced_bt_coexist &&
825 priv->bt_full_concurrent) {
826 /* operated as 1x1 in full concurrency mode */
827 rx_ant = first_antenna(rx_ant);
828 }
829
830 /* MIMO is not used here, but value is required */
831 rx_chain |=
832 priv->nvm_data->valid_rx_ant << RXON_RX_CHAIN_VALID_POS;
833 rx_chain |= rx_ant << RXON_RX_CHAIN_FORCE_MIMO_SEL_POS;
834 rx_chain |= rx_ant << RXON_RX_CHAIN_FORCE_SEL_POS;
835 rx_chain |= 0x1 << RXON_RX_CHAIN_DRIVER_FORCE_POS;
836 scan->rx_chain = cpu_to_le16(rx_chain);
837 switch (priv->scan_type) {
838 case IWL_SCAN_NORMAL:
839 cmd_len = iwl_fill_probe_req(
840 (struct ieee80211_mgmt *)scan->data,
841 vif->addr,
842 priv->scan_request->ie,
843 priv->scan_request->ie_len,
844 ssid, ssid_len,
845 scan_cmd_size - sizeof(*scan));
846 break;
847 case IWL_SCAN_RADIO_RESET:
848 /* use bcast addr, will not be transmitted but must be valid */
849 cmd_len = iwl_fill_probe_req(
850 (struct ieee80211_mgmt *)scan->data,
851 iwl_bcast_addr, NULL, 0,
852 NULL, 0,
853 scan_cmd_size - sizeof(*scan));
854 break;
855 default:
856 BUG();
857 }
858 scan->tx_cmd.len = cpu_to_le16(cmd_len);
859
860 scan->filter_flags |= (RXON_FILTER_ACCEPT_GRP_MSK |
861 RXON_FILTER_BCON_AWARE_MSK);
862
863 switch (priv->scan_type) {
864 case IWL_SCAN_RADIO_RESET:
865 scan->channel_count =
866 iwl_get_channel_for_reset_scan(priv, vif, band,
867 (void *)&scan->data[cmd_len]);
868 break;
869 case IWL_SCAN_NORMAL:
870 scan->channel_count =
871 iwl_get_channels_for_scan(priv, vif, band,
872 is_active, n_probes,
873 (void *)&scan->data[cmd_len]);
874 break;
875 }
876
877 if (scan->channel_count == 0) {
878 IWL_DEBUG_SCAN(priv, "channel count %d\n", scan->channel_count);
879 return -EIO;
880 }
881
882 cmd.len[0] += le16_to_cpu(scan->tx_cmd.len) +
883 scan->channel_count * sizeof(struct iwl_scan_channel);
884 cmd.data[0] = scan;
885 cmd.dataflags[0] = IWL_HCMD_DFL_NOCOPY;
886 scan->len = cpu_to_le16(cmd.len[0]);
887
888 /* set scan bit here for PAN params */
889 set_bit(STATUS_SCAN_HW, &priv->status);
890
891 ret = iwlagn_set_pan_params(priv);
892 if (ret) {
893 clear_bit(STATUS_SCAN_HW, &priv->status);
894 return ret;
895 }
896
897 ret = iwl_dvm_send_cmd(priv, &cmd);
898 if (ret) {
899 clear_bit(STATUS_SCAN_HW, &priv->status);
900 iwlagn_set_pan_params(priv);
901 }
902
903 return ret;
904 }
905
iwl_init_scan_params(struct iwl_priv * priv)906 void iwl_init_scan_params(struct iwl_priv *priv)
907 {
908 u8 ant_idx = fls(priv->nvm_data->valid_tx_ant) - 1;
909 if (!priv->scan_tx_ant[NL80211_BAND_5GHZ])
910 priv->scan_tx_ant[NL80211_BAND_5GHZ] = ant_idx;
911 if (!priv->scan_tx_ant[NL80211_BAND_2GHZ])
912 priv->scan_tx_ant[NL80211_BAND_2GHZ] = ant_idx;
913 }
914
iwl_scan_initiate(struct iwl_priv * priv,struct ieee80211_vif * vif,enum iwl_scan_type scan_type,enum nl80211_band band)915 int __must_check iwl_scan_initiate(struct iwl_priv *priv,
916 struct ieee80211_vif *vif,
917 enum iwl_scan_type scan_type,
918 enum nl80211_band band)
919 {
920 int ret;
921
922 lockdep_assert_held(&priv->mutex);
923
924 cancel_delayed_work(&priv->scan_check);
925
926 if (!iwl_is_ready_rf(priv)) {
927 IWL_WARN(priv, "Request scan called when driver not ready.\n");
928 return -EIO;
929 }
930
931 if (test_bit(STATUS_SCAN_HW, &priv->status)) {
932 IWL_DEBUG_SCAN(priv,
933 "Multiple concurrent scan requests in parallel.\n");
934 return -EBUSY;
935 }
936
937 if (test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
938 IWL_DEBUG_SCAN(priv, "Scan request while abort pending.\n");
939 return -EBUSY;
940 }
941
942 IWL_DEBUG_SCAN(priv, "Starting %sscan...\n",
943 scan_type == IWL_SCAN_NORMAL ? "" :
944 "internal short ");
945
946 set_bit(STATUS_SCANNING, &priv->status);
947 priv->scan_type = scan_type;
948 priv->scan_start = jiffies;
949 priv->scan_band = band;
950
951 ret = iwlagn_request_scan(priv, vif);
952 if (ret) {
953 clear_bit(STATUS_SCANNING, &priv->status);
954 priv->scan_type = IWL_SCAN_NORMAL;
955 return ret;
956 }
957
958 queue_delayed_work(priv->workqueue, &priv->scan_check,
959 IWL_SCAN_CHECK_WATCHDOG);
960
961 return 0;
962 }
963
964
965 /*
966 * internal short scan, this function should only been called while associated.
967 * It will reset and tune the radio to prevent possible RF related problem
968 */
iwl_internal_short_hw_scan(struct iwl_priv * priv)969 void iwl_internal_short_hw_scan(struct iwl_priv *priv)
970 {
971 queue_work(priv->workqueue, &priv->start_internal_scan);
972 }
973
iwl_bg_start_internal_scan(struct work_struct * work)974 static void iwl_bg_start_internal_scan(struct work_struct *work)
975 {
976 struct iwl_priv *priv =
977 container_of(work, struct iwl_priv, start_internal_scan);
978
979 IWL_DEBUG_SCAN(priv, "Start internal scan\n");
980
981 mutex_lock(&priv->mutex);
982
983 if (priv->scan_type == IWL_SCAN_RADIO_RESET) {
984 IWL_DEBUG_SCAN(priv, "Internal scan already in progress\n");
985 goto unlock;
986 }
987
988 if (test_bit(STATUS_SCANNING, &priv->status)) {
989 IWL_DEBUG_SCAN(priv, "Scan already in progress.\n");
990 goto unlock;
991 }
992
993 if (iwl_scan_initiate(priv, NULL, IWL_SCAN_RADIO_RESET, priv->band))
994 IWL_DEBUG_SCAN(priv, "failed to start internal short scan\n");
995 unlock:
996 mutex_unlock(&priv->mutex);
997 }
998
iwl_bg_scan_check(struct work_struct * data)999 static void iwl_bg_scan_check(struct work_struct *data)
1000 {
1001 struct iwl_priv *priv =
1002 container_of(data, struct iwl_priv, scan_check.work);
1003
1004 IWL_DEBUG_SCAN(priv, "Scan check work\n");
1005
1006 /* Since we are here firmware does not finish scan and
1007 * most likely is in bad shape, so we don't bother to
1008 * send abort command, just force scan complete to mac80211 */
1009 mutex_lock(&priv->mutex);
1010 iwl_force_scan_end(priv);
1011 mutex_unlock(&priv->mutex);
1012 }
1013
iwl_bg_abort_scan(struct work_struct * work)1014 static void iwl_bg_abort_scan(struct work_struct *work)
1015 {
1016 struct iwl_priv *priv = container_of(work, struct iwl_priv, abort_scan);
1017
1018 IWL_DEBUG_SCAN(priv, "Abort scan work\n");
1019
1020 /* We keep scan_check work queued in case when firmware will not
1021 * report back scan completed notification */
1022 mutex_lock(&priv->mutex);
1023 iwl_scan_cancel_timeout(priv, 200);
1024 mutex_unlock(&priv->mutex);
1025 }
1026
iwl_bg_scan_completed(struct work_struct * work)1027 static void iwl_bg_scan_completed(struct work_struct *work)
1028 {
1029 struct iwl_priv *priv =
1030 container_of(work, struct iwl_priv, scan_completed);
1031
1032 mutex_lock(&priv->mutex);
1033 iwl_process_scan_complete(priv);
1034 mutex_unlock(&priv->mutex);
1035 }
1036
iwl_setup_scan_deferred_work(struct iwl_priv * priv)1037 void iwl_setup_scan_deferred_work(struct iwl_priv *priv)
1038 {
1039 INIT_WORK(&priv->scan_completed, iwl_bg_scan_completed);
1040 INIT_WORK(&priv->abort_scan, iwl_bg_abort_scan);
1041 INIT_WORK(&priv->start_internal_scan, iwl_bg_start_internal_scan);
1042 INIT_DELAYED_WORK(&priv->scan_check, iwl_bg_scan_check);
1043 }
1044
iwl_cancel_scan_deferred_work(struct iwl_priv * priv)1045 void iwl_cancel_scan_deferred_work(struct iwl_priv *priv)
1046 {
1047 cancel_work_sync(&priv->start_internal_scan);
1048 cancel_work_sync(&priv->abort_scan);
1049 cancel_work_sync(&priv->scan_completed);
1050
1051 if (cancel_delayed_work_sync(&priv->scan_check)) {
1052 mutex_lock(&priv->mutex);
1053 iwl_force_scan_end(priv);
1054 mutex_unlock(&priv->mutex);
1055 }
1056 }
1057