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 size_t 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 priv->scan_cmd_size = scan_cmd_size;
653 }
654 if (priv->scan_cmd_size < scan_cmd_size) {
655 IWL_DEBUG_SCAN(priv,
656 "memory needed for scan grew unexpectedly\n");
657 return -ENOMEM;
658 }
659 scan = priv->scan_cmd;
660 memset(scan, 0, priv->scan_cmd_size);
661
662 scan->quiet_plcp_th = IWL_PLCP_QUIET_THRESH;
663 scan->quiet_time = IWL_ACTIVE_QUIET_TIME;
664
665 if (iwl_is_any_associated(priv)) {
666 u16 interval = 0;
667 u32 extra;
668 u32 suspend_time = 100;
669 u32 scan_suspend_time = 100;
670
671 IWL_DEBUG_INFO(priv, "Scanning while associated...\n");
672 switch (priv->scan_type) {
673 case IWL_SCAN_RADIO_RESET:
674 interval = 0;
675 break;
676 case IWL_SCAN_NORMAL:
677 interval = vif->bss_conf.beacon_int;
678 break;
679 }
680
681 scan->suspend_time = 0;
682 scan->max_out_time = cpu_to_le32(200 * 1024);
683 if (!interval)
684 interval = suspend_time;
685
686 extra = (suspend_time / interval) << 22;
687 scan_suspend_time = (extra |
688 ((suspend_time % interval) * 1024));
689 scan->suspend_time = cpu_to_le32(scan_suspend_time);
690 IWL_DEBUG_SCAN(priv, "suspend_time 0x%X beacon interval %d\n",
691 scan_suspend_time, interval);
692 }
693
694 switch (priv->scan_type) {
695 case IWL_SCAN_RADIO_RESET:
696 IWL_DEBUG_SCAN(priv, "Start internal passive scan.\n");
697 /*
698 * Override quiet time as firmware checks that active
699 * dwell is >= quiet; since we use passive scan it'll
700 * not actually be used.
701 */
702 scan->quiet_time = cpu_to_le16(IWL_RADIO_RESET_DWELL_TIME);
703 break;
704 case IWL_SCAN_NORMAL:
705 if (priv->scan_request->n_ssids) {
706 int i, p = 0;
707 IWL_DEBUG_SCAN(priv, "Kicking off active scan\n");
708 /*
709 * The highest priority SSID is inserted to the
710 * probe request template.
711 */
712 ssid_len = priv->scan_request->ssids[0].ssid_len;
713 ssid = priv->scan_request->ssids[0].ssid;
714
715 /*
716 * Invert the order of ssids, the firmware will invert
717 * it back.
718 */
719 for (i = priv->scan_request->n_ssids - 1; i >= 1; i--) {
720 scan->direct_scan[p].id = WLAN_EID_SSID;
721 scan->direct_scan[p].len =
722 priv->scan_request->ssids[i].ssid_len;
723 memcpy(scan->direct_scan[p].ssid,
724 priv->scan_request->ssids[i].ssid,
725 priv->scan_request->ssids[i].ssid_len);
726 n_probes++;
727 p++;
728 }
729 is_active = true;
730 } else
731 IWL_DEBUG_SCAN(priv, "Start passive scan.\n");
732 break;
733 }
734
735 scan->tx_cmd.tx_flags = TX_CMD_FLG_SEQ_CTL_MSK;
736 scan->tx_cmd.sta_id = ctx->bcast_sta_id;
737 scan->tx_cmd.stop_time.life_time = TX_CMD_LIFE_TIME_INFINITE;
738
739 switch (priv->scan_band) {
740 case NL80211_BAND_2GHZ:
741 scan->flags = RXON_FLG_BAND_24G_MSK | RXON_FLG_AUTO_DETECT_MSK;
742 chan_mod = le32_to_cpu(
743 priv->contexts[IWL_RXON_CTX_BSS].active.flags &
744 RXON_FLG_CHANNEL_MODE_MSK)
745 >> RXON_FLG_CHANNEL_MODE_POS;
746 if ((priv->scan_request && priv->scan_request->no_cck) ||
747 chan_mod == CHANNEL_MODE_PURE_40) {
748 rate = IWL_RATE_6M_PLCP;
749 } else {
750 rate = IWL_RATE_1M_PLCP;
751 rate_flags = RATE_MCS_CCK_MSK;
752 }
753 /*
754 * Internal scans are passive, so we can indiscriminately set
755 * the BT ignore flag on 2.4 GHz since it applies to TX only.
756 */
757 if (priv->lib->bt_params &&
758 priv->lib->bt_params->advanced_bt_coexist)
759 scan->tx_cmd.tx_flags |= TX_CMD_FLG_IGNORE_BT;
760 break;
761 case NL80211_BAND_5GHZ:
762 rate = IWL_RATE_6M_PLCP;
763 break;
764 default:
765 IWL_WARN(priv, "Invalid scan band\n");
766 return -EIO;
767 }
768
769 /*
770 * If active scanning is requested but a certain channel is
771 * marked passive, we can do active scanning if we detect
772 * transmissions.
773 *
774 * There is an issue with some firmware versions that triggers
775 * a sysassert on a "good CRC threshold" of zero (== disabled),
776 * on a radar channel even though this means that we should NOT
777 * send probes.
778 *
779 * The "good CRC threshold" is the number of frames that we
780 * need to receive during our dwell time on a channel before
781 * sending out probes -- setting this to a huge value will
782 * mean we never reach it, but at the same time work around
783 * the aforementioned issue. Thus use IWL_GOOD_CRC_TH_NEVER
784 * here instead of IWL_GOOD_CRC_TH_DISABLED.
785 *
786 * This was fixed in later versions along with some other
787 * scan changes, and the threshold behaves as a flag in those
788 * versions.
789 */
790 if (priv->new_scan_threshold_behaviour)
791 scan->good_CRC_th = is_active ? IWL_GOOD_CRC_TH_DEFAULT :
792 IWL_GOOD_CRC_TH_DISABLED;
793 else
794 scan->good_CRC_th = is_active ? IWL_GOOD_CRC_TH_DEFAULT :
795 IWL_GOOD_CRC_TH_NEVER;
796
797 band = priv->scan_band;
798
799 if (band == NL80211_BAND_2GHZ &&
800 priv->lib->bt_params &&
801 priv->lib->bt_params->advanced_bt_coexist) {
802 /* transmit 2.4 GHz probes only on first antenna */
803 scan_tx_antennas = first_antenna(scan_tx_antennas);
804 }
805
806 priv->scan_tx_ant[band] = iwl_toggle_tx_ant(priv,
807 priv->scan_tx_ant[band],
808 scan_tx_antennas);
809 rate_flags |= iwl_ant_idx_to_flags(priv->scan_tx_ant[band]);
810 scan->tx_cmd.rate_n_flags = iwl_hw_set_rate_n_flags(rate, rate_flags);
811
812 /*
813 * In power save mode while associated use one chain,
814 * otherwise use all chains
815 */
816 if (test_bit(STATUS_POWER_PMI, &priv->status) &&
817 !(priv->hw->conf.flags & IEEE80211_CONF_IDLE)) {
818 /* rx_ant has been set to all valid chains previously */
819 active_chains = rx_ant &
820 ((u8)(priv->chain_noise_data.active_chains));
821 if (!active_chains)
822 active_chains = rx_ant;
823
824 IWL_DEBUG_SCAN(priv, "chain_noise_data.active_chains: %u\n",
825 priv->chain_noise_data.active_chains);
826
827 rx_ant = first_antenna(active_chains);
828 }
829 if (priv->lib->bt_params &&
830 priv->lib->bt_params->advanced_bt_coexist &&
831 priv->bt_full_concurrent) {
832 /* operated as 1x1 in full concurrency mode */
833 rx_ant = first_antenna(rx_ant);
834 }
835
836 /* MIMO is not used here, but value is required */
837 rx_chain |=
838 priv->nvm_data->valid_rx_ant << RXON_RX_CHAIN_VALID_POS;
839 rx_chain |= rx_ant << RXON_RX_CHAIN_FORCE_MIMO_SEL_POS;
840 rx_chain |= rx_ant << RXON_RX_CHAIN_FORCE_SEL_POS;
841 rx_chain |= 0x1 << RXON_RX_CHAIN_DRIVER_FORCE_POS;
842 scan->rx_chain = cpu_to_le16(rx_chain);
843 switch (priv->scan_type) {
844 case IWL_SCAN_NORMAL:
845 cmd_len = iwl_fill_probe_req(
846 (struct ieee80211_mgmt *)scan->data,
847 vif->addr,
848 priv->scan_request->ie,
849 priv->scan_request->ie_len,
850 ssid, ssid_len,
851 scan_cmd_size - sizeof(*scan));
852 break;
853 case IWL_SCAN_RADIO_RESET:
854 /* use bcast addr, will not be transmitted but must be valid */
855 cmd_len = iwl_fill_probe_req(
856 (struct ieee80211_mgmt *)scan->data,
857 iwl_bcast_addr, NULL, 0,
858 NULL, 0,
859 scan_cmd_size - sizeof(*scan));
860 break;
861 default:
862 BUG();
863 }
864 scan->tx_cmd.len = cpu_to_le16(cmd_len);
865
866 scan->filter_flags |= (RXON_FILTER_ACCEPT_GRP_MSK |
867 RXON_FILTER_BCON_AWARE_MSK);
868
869 switch (priv->scan_type) {
870 case IWL_SCAN_RADIO_RESET:
871 scan->channel_count =
872 iwl_get_channel_for_reset_scan(priv, vif, band,
873 (void *)&scan->data[cmd_len]);
874 break;
875 case IWL_SCAN_NORMAL:
876 scan->channel_count =
877 iwl_get_channels_for_scan(priv, vif, band,
878 is_active, n_probes,
879 (void *)&scan->data[cmd_len]);
880 break;
881 }
882
883 if (scan->channel_count == 0) {
884 IWL_DEBUG_SCAN(priv, "channel count %d\n", scan->channel_count);
885 return -EIO;
886 }
887
888 cmd.len[0] += le16_to_cpu(scan->tx_cmd.len) +
889 scan->channel_count * sizeof(struct iwl_scan_channel);
890 cmd.data[0] = scan;
891 cmd.dataflags[0] = IWL_HCMD_DFL_NOCOPY;
892 scan->len = cpu_to_le16(cmd.len[0]);
893
894 /* set scan bit here for PAN params */
895 set_bit(STATUS_SCAN_HW, &priv->status);
896
897 ret = iwlagn_set_pan_params(priv);
898 if (ret) {
899 clear_bit(STATUS_SCAN_HW, &priv->status);
900 return ret;
901 }
902
903 ret = iwl_dvm_send_cmd(priv, &cmd);
904 if (ret) {
905 clear_bit(STATUS_SCAN_HW, &priv->status);
906 iwlagn_set_pan_params(priv);
907 }
908
909 return ret;
910 }
911
iwl_init_scan_params(struct iwl_priv * priv)912 void iwl_init_scan_params(struct iwl_priv *priv)
913 {
914 u8 ant_idx = fls(priv->nvm_data->valid_tx_ant) - 1;
915 if (!priv->scan_tx_ant[NL80211_BAND_5GHZ])
916 priv->scan_tx_ant[NL80211_BAND_5GHZ] = ant_idx;
917 if (!priv->scan_tx_ant[NL80211_BAND_2GHZ])
918 priv->scan_tx_ant[NL80211_BAND_2GHZ] = ant_idx;
919 }
920
iwl_scan_initiate(struct iwl_priv * priv,struct ieee80211_vif * vif,enum iwl_scan_type scan_type,enum nl80211_band band)921 int __must_check iwl_scan_initiate(struct iwl_priv *priv,
922 struct ieee80211_vif *vif,
923 enum iwl_scan_type scan_type,
924 enum nl80211_band band)
925 {
926 int ret;
927
928 lockdep_assert_held(&priv->mutex);
929
930 cancel_delayed_work(&priv->scan_check);
931
932 if (!iwl_is_ready_rf(priv)) {
933 IWL_WARN(priv, "Request scan called when driver not ready.\n");
934 return -EIO;
935 }
936
937 if (test_bit(STATUS_SCAN_HW, &priv->status)) {
938 IWL_DEBUG_SCAN(priv,
939 "Multiple concurrent scan requests in parallel.\n");
940 return -EBUSY;
941 }
942
943 if (test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
944 IWL_DEBUG_SCAN(priv, "Scan request while abort pending.\n");
945 return -EBUSY;
946 }
947
948 IWL_DEBUG_SCAN(priv, "Starting %sscan...\n",
949 scan_type == IWL_SCAN_NORMAL ? "" :
950 "internal short ");
951
952 set_bit(STATUS_SCANNING, &priv->status);
953 priv->scan_type = scan_type;
954 priv->scan_start = jiffies;
955 priv->scan_band = band;
956
957 ret = iwlagn_request_scan(priv, vif);
958 if (ret) {
959 clear_bit(STATUS_SCANNING, &priv->status);
960 priv->scan_type = IWL_SCAN_NORMAL;
961 return ret;
962 }
963
964 queue_delayed_work(priv->workqueue, &priv->scan_check,
965 IWL_SCAN_CHECK_WATCHDOG);
966
967 return 0;
968 }
969
970
971 /*
972 * internal short scan, this function should only been called while associated.
973 * It will reset and tune the radio to prevent possible RF related problem
974 */
iwl_internal_short_hw_scan(struct iwl_priv * priv)975 void iwl_internal_short_hw_scan(struct iwl_priv *priv)
976 {
977 queue_work(priv->workqueue, &priv->start_internal_scan);
978 }
979
iwl_bg_start_internal_scan(struct work_struct * work)980 static void iwl_bg_start_internal_scan(struct work_struct *work)
981 {
982 struct iwl_priv *priv =
983 container_of(work, struct iwl_priv, start_internal_scan);
984
985 IWL_DEBUG_SCAN(priv, "Start internal scan\n");
986
987 mutex_lock(&priv->mutex);
988
989 if (priv->scan_type == IWL_SCAN_RADIO_RESET) {
990 IWL_DEBUG_SCAN(priv, "Internal scan already in progress\n");
991 goto unlock;
992 }
993
994 if (test_bit(STATUS_SCANNING, &priv->status)) {
995 IWL_DEBUG_SCAN(priv, "Scan already in progress.\n");
996 goto unlock;
997 }
998
999 if (iwl_scan_initiate(priv, NULL, IWL_SCAN_RADIO_RESET, priv->band))
1000 IWL_DEBUG_SCAN(priv, "failed to start internal short scan\n");
1001 unlock:
1002 mutex_unlock(&priv->mutex);
1003 }
1004
iwl_bg_scan_check(struct work_struct * data)1005 static void iwl_bg_scan_check(struct work_struct *data)
1006 {
1007 struct iwl_priv *priv =
1008 container_of(data, struct iwl_priv, scan_check.work);
1009
1010 IWL_DEBUG_SCAN(priv, "Scan check work\n");
1011
1012 /* Since we are here firmware does not finish scan and
1013 * most likely is in bad shape, so we don't bother to
1014 * send abort command, just force scan complete to mac80211 */
1015 mutex_lock(&priv->mutex);
1016 iwl_force_scan_end(priv);
1017 mutex_unlock(&priv->mutex);
1018 }
1019
iwl_bg_abort_scan(struct work_struct * work)1020 static void iwl_bg_abort_scan(struct work_struct *work)
1021 {
1022 struct iwl_priv *priv = container_of(work, struct iwl_priv, abort_scan);
1023
1024 IWL_DEBUG_SCAN(priv, "Abort scan work\n");
1025
1026 /* We keep scan_check work queued in case when firmware will not
1027 * report back scan completed notification */
1028 mutex_lock(&priv->mutex);
1029 iwl_scan_cancel_timeout(priv, 200);
1030 mutex_unlock(&priv->mutex);
1031 }
1032
iwl_bg_scan_completed(struct work_struct * work)1033 static void iwl_bg_scan_completed(struct work_struct *work)
1034 {
1035 struct iwl_priv *priv =
1036 container_of(work, struct iwl_priv, scan_completed);
1037
1038 mutex_lock(&priv->mutex);
1039 iwl_process_scan_complete(priv);
1040 mutex_unlock(&priv->mutex);
1041 }
1042
iwl_setup_scan_deferred_work(struct iwl_priv * priv)1043 void iwl_setup_scan_deferred_work(struct iwl_priv *priv)
1044 {
1045 INIT_WORK(&priv->scan_completed, iwl_bg_scan_completed);
1046 INIT_WORK(&priv->abort_scan, iwl_bg_abort_scan);
1047 INIT_WORK(&priv->start_internal_scan, iwl_bg_start_internal_scan);
1048 INIT_DELAYED_WORK(&priv->scan_check, iwl_bg_scan_check);
1049 }
1050
iwl_cancel_scan_deferred_work(struct iwl_priv * priv)1051 void iwl_cancel_scan_deferred_work(struct iwl_priv *priv)
1052 {
1053 cancel_work_sync(&priv->start_internal_scan);
1054 cancel_work_sync(&priv->abort_scan);
1055 cancel_work_sync(&priv->scan_completed);
1056
1057 if (cancel_delayed_work_sync(&priv->scan_check)) {
1058 mutex_lock(&priv->mutex);
1059 iwl_force_scan_end(priv);
1060 mutex_unlock(&priv->mutex);
1061 }
1062 }
1063