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 * Contact Information:
8 * Intel Linux Wireless <linuxwifi@intel.com>
9 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
10 *****************************************************************************/
11 #include <linux/slab.h>
12 #include <linux/types.h>
13 #include <linux/etherdevice.h>
14 #include <net/mac80211.h>
15
16 #include "dev.h"
17 #include "agn.h"
18
19 /* For active scan, listen ACTIVE_DWELL_TIME (msec) on each channel after
20 * sending probe req. This should be set long enough to hear probe responses
21 * from more than one AP. */
22 #define IWL_ACTIVE_DWELL_TIME_24 (30) /* all times in msec */
23 #define IWL_ACTIVE_DWELL_TIME_52 (20)
24
25 #define IWL_ACTIVE_DWELL_FACTOR_24GHZ (3)
26 #define IWL_ACTIVE_DWELL_FACTOR_52GHZ (2)
27
28 /* For passive scan, listen PASSIVE_DWELL_TIME (msec) on each channel.
29 * Must be set longer than active dwell time.
30 * For the most reliable scan, set > AP beacon interval (typically 100msec). */
31 #define IWL_PASSIVE_DWELL_TIME_24 (20) /* all times in msec */
32 #define IWL_PASSIVE_DWELL_TIME_52 (10)
33 #define IWL_PASSIVE_DWELL_BASE (100)
34 #define IWL_CHANNEL_TUNE_TIME 5
35 #define MAX_SCAN_CHANNEL 50
36
37 /* For reset radio, need minimal dwell time only */
38 #define IWL_RADIO_RESET_DWELL_TIME 5
39
iwl_send_scan_abort(struct iwl_priv * priv)40 static int iwl_send_scan_abort(struct iwl_priv *priv)
41 {
42 int ret;
43 struct iwl_host_cmd cmd = {
44 .id = REPLY_SCAN_ABORT_CMD,
45 .flags = CMD_WANT_SKB,
46 };
47 __le32 *status;
48
49 /* Exit instantly with error when device is not ready
50 * to receive scan abort command or it does not perform
51 * hardware scan currently */
52 if (!test_bit(STATUS_READY, &priv->status) ||
53 !test_bit(STATUS_SCAN_HW, &priv->status) ||
54 test_bit(STATUS_FW_ERROR, &priv->status))
55 return -EIO;
56
57 ret = iwl_dvm_send_cmd(priv, &cmd);
58 if (ret)
59 return ret;
60
61 status = (void *)cmd.resp_pkt->data;
62 if (*status != CAN_ABORT_STATUS) {
63 /* The scan abort will return 1 for success or
64 * 2 for "failure". A failure condition can be
65 * due to simply not being in an active scan which
66 * can occur if we send the scan abort before we
67 * the microcode has notified us that a scan is
68 * completed. */
69 IWL_DEBUG_SCAN(priv, "SCAN_ABORT ret %d.\n",
70 le32_to_cpu(*status));
71 ret = -EIO;
72 }
73
74 iwl_free_resp(&cmd);
75 return ret;
76 }
77
iwl_complete_scan(struct iwl_priv * priv,bool aborted)78 static void iwl_complete_scan(struct iwl_priv *priv, bool aborted)
79 {
80 struct cfg80211_scan_info info = {
81 .aborted = aborted,
82 };
83
84 /* check if scan was requested from mac80211 */
85 if (priv->scan_request) {
86 IWL_DEBUG_SCAN(priv, "Complete scan in mac80211\n");
87 ieee80211_scan_completed(priv->hw, &info);
88 }
89
90 priv->scan_type = IWL_SCAN_NORMAL;
91 priv->scan_vif = NULL;
92 priv->scan_request = NULL;
93 }
94
iwl_process_scan_complete(struct iwl_priv * priv)95 static void iwl_process_scan_complete(struct iwl_priv *priv)
96 {
97 bool aborted;
98
99 lockdep_assert_held(&priv->mutex);
100
101 if (!test_and_clear_bit(STATUS_SCAN_COMPLETE, &priv->status))
102 return;
103
104 IWL_DEBUG_SCAN(priv, "Completed scan.\n");
105
106 cancel_delayed_work(&priv->scan_check);
107
108 aborted = test_and_clear_bit(STATUS_SCAN_ABORTING, &priv->status);
109 if (aborted)
110 IWL_DEBUG_SCAN(priv, "Aborted scan completed.\n");
111
112 if (!test_and_clear_bit(STATUS_SCANNING, &priv->status)) {
113 IWL_DEBUG_SCAN(priv, "Scan already completed.\n");
114 goto out_settings;
115 }
116
117 if (priv->scan_type != IWL_SCAN_NORMAL && !aborted) {
118 int err;
119
120 /* Check if mac80211 requested scan during our internal scan */
121 if (priv->scan_request == NULL)
122 goto out_complete;
123
124 /* If so request a new scan */
125 err = iwl_scan_initiate(priv, priv->scan_vif, IWL_SCAN_NORMAL,
126 priv->scan_request->channels[0]->band);
127 if (err) {
128 IWL_DEBUG_SCAN(priv,
129 "failed to initiate pending scan: %d\n", err);
130 aborted = true;
131 goto out_complete;
132 }
133
134 return;
135 }
136
137 out_complete:
138 iwl_complete_scan(priv, aborted);
139
140 out_settings:
141 /* Can we still talk to firmware ? */
142 if (!iwl_is_ready_rf(priv))
143 return;
144
145 iwlagn_post_scan(priv);
146 }
147
iwl_force_scan_end(struct iwl_priv * priv)148 void iwl_force_scan_end(struct iwl_priv *priv)
149 {
150 lockdep_assert_held(&priv->mutex);
151
152 if (!test_bit(STATUS_SCANNING, &priv->status)) {
153 IWL_DEBUG_SCAN(priv, "Forcing scan end while not scanning\n");
154 return;
155 }
156
157 IWL_DEBUG_SCAN(priv, "Forcing scan end\n");
158 clear_bit(STATUS_SCANNING, &priv->status);
159 clear_bit(STATUS_SCAN_HW, &priv->status);
160 clear_bit(STATUS_SCAN_ABORTING, &priv->status);
161 clear_bit(STATUS_SCAN_COMPLETE, &priv->status);
162 iwl_complete_scan(priv, true);
163 }
164
iwl_do_scan_abort(struct iwl_priv * priv)165 static void iwl_do_scan_abort(struct iwl_priv *priv)
166 {
167 int ret;
168
169 lockdep_assert_held(&priv->mutex);
170
171 if (!test_bit(STATUS_SCANNING, &priv->status)) {
172 IWL_DEBUG_SCAN(priv, "Not performing scan to abort\n");
173 return;
174 }
175
176 if (test_and_set_bit(STATUS_SCAN_ABORTING, &priv->status)) {
177 IWL_DEBUG_SCAN(priv, "Scan abort in progress\n");
178 return;
179 }
180
181 ret = iwl_send_scan_abort(priv);
182 if (ret) {
183 IWL_DEBUG_SCAN(priv, "Send scan abort failed %d\n", ret);
184 iwl_force_scan_end(priv);
185 } else
186 IWL_DEBUG_SCAN(priv, "Successfully send scan abort\n");
187 }
188
189 /*
190 * iwl_scan_cancel - Cancel any currently executing HW scan
191 */
iwl_scan_cancel(struct iwl_priv * priv)192 int iwl_scan_cancel(struct iwl_priv *priv)
193 {
194 IWL_DEBUG_SCAN(priv, "Queuing abort scan\n");
195 queue_work(priv->workqueue, &priv->abort_scan);
196 return 0;
197 }
198
199 /*
200 * iwl_scan_cancel_timeout - Cancel any currently executing HW scan
201 * @ms: amount of time to wait (in milliseconds) for scan to abort
202 */
iwl_scan_cancel_timeout(struct iwl_priv * priv,unsigned long ms)203 void iwl_scan_cancel_timeout(struct iwl_priv *priv, unsigned long ms)
204 {
205 unsigned long timeout = jiffies + msecs_to_jiffies(ms);
206
207 lockdep_assert_held(&priv->mutex);
208
209 IWL_DEBUG_SCAN(priv, "Scan cancel timeout\n");
210
211 iwl_do_scan_abort(priv);
212
213 while (time_before_eq(jiffies, timeout)) {
214 if (!test_bit(STATUS_SCAN_HW, &priv->status))
215 goto finished;
216 msleep(20);
217 }
218
219 return;
220
221 finished:
222 /*
223 * Now STATUS_SCAN_HW is clear. This means that the
224 * device finished, but the background work is going
225 * to execute at best as soon as we release the mutex.
226 * Since we need to be able to issue a new scan right
227 * after this function returns, run the complete here.
228 * The STATUS_SCAN_COMPLETE bit will then be cleared
229 * and prevent the background work from "completing"
230 * a possible new scan.
231 */
232 iwl_process_scan_complete(priv);
233 }
234
235 /* Service response to REPLY_SCAN_CMD (0x80) */
iwl_rx_reply_scan(struct iwl_priv * priv,struct iwl_rx_cmd_buffer * rxb)236 static void iwl_rx_reply_scan(struct iwl_priv *priv,
237 struct iwl_rx_cmd_buffer *rxb)
238 {
239 #ifdef CONFIG_IWLWIFI_DEBUG
240 struct iwl_rx_packet *pkt = rxb_addr(rxb);
241 struct iwl_scanreq_notification *notif = (void *)pkt->data;
242
243 IWL_DEBUG_SCAN(priv, "Scan request status = 0x%x\n", notif->status);
244 #endif
245 }
246
247 /* Service SCAN_START_NOTIFICATION (0x82) */
iwl_rx_scan_start_notif(struct iwl_priv * priv,struct iwl_rx_cmd_buffer * rxb)248 static void iwl_rx_scan_start_notif(struct iwl_priv *priv,
249 struct iwl_rx_cmd_buffer *rxb)
250 {
251 struct iwl_rx_packet *pkt = rxb_addr(rxb);
252 struct iwl_scanstart_notification *notif = (void *)pkt->data;
253
254 priv->scan_start_tsf = le32_to_cpu(notif->tsf_low);
255 IWL_DEBUG_SCAN(priv, "Scan start: "
256 "%d [802.11%s] "
257 "(TSF: 0x%08X:%08X) - %d (beacon timer %u)\n",
258 notif->channel,
259 notif->band ? "bg" : "a",
260 le32_to_cpu(notif->tsf_high),
261 le32_to_cpu(notif->tsf_low),
262 notif->status, notif->beacon_timer);
263 }
264
265 /* Service SCAN_RESULTS_NOTIFICATION (0x83) */
iwl_rx_scan_results_notif(struct iwl_priv * priv,struct iwl_rx_cmd_buffer * rxb)266 static void iwl_rx_scan_results_notif(struct iwl_priv *priv,
267 struct iwl_rx_cmd_buffer *rxb)
268 {
269 #ifdef CONFIG_IWLWIFI_DEBUG
270 struct iwl_rx_packet *pkt = rxb_addr(rxb);
271 struct iwl_scanresults_notification *notif = (void *)pkt->data;
272
273 IWL_DEBUG_SCAN(priv, "Scan ch.res: "
274 "%d [802.11%s] "
275 "probe status: %u:%u "
276 "(TSF: 0x%08X:%08X) - %d "
277 "elapsed=%lu usec\n",
278 notif->channel,
279 notif->band ? "bg" : "a",
280 notif->probe_status, notif->num_probe_not_sent,
281 le32_to_cpu(notif->tsf_high),
282 le32_to_cpu(notif->tsf_low),
283 le32_to_cpu(notif->statistics[0]),
284 le32_to_cpu(notif->tsf_low) - priv->scan_start_tsf);
285 #endif
286 }
287
288 /* Service SCAN_COMPLETE_NOTIFICATION (0x84) */
iwl_rx_scan_complete_notif(struct iwl_priv * priv,struct iwl_rx_cmd_buffer * rxb)289 static void iwl_rx_scan_complete_notif(struct iwl_priv *priv,
290 struct iwl_rx_cmd_buffer *rxb)
291 {
292 struct iwl_rx_packet *pkt = rxb_addr(rxb);
293 struct iwl_scancomplete_notification *scan_notif = (void *)pkt->data;
294
295 IWL_DEBUG_SCAN(priv, "Scan complete: %d channels (TSF 0x%08X:%08X) - %d\n",
296 scan_notif->scanned_channels,
297 scan_notif->tsf_low,
298 scan_notif->tsf_high, scan_notif->status);
299
300 IWL_DEBUG_SCAN(priv, "Scan on %sGHz took %dms\n",
301 (priv->scan_band == NL80211_BAND_2GHZ) ? "2.4" : "5.2",
302 jiffies_to_msecs(jiffies - priv->scan_start));
303
304 /*
305 * When aborting, we run the scan completed background work inline
306 * and the background work must then do nothing. The SCAN_COMPLETE
307 * bit helps implement that logic and thus needs to be set before
308 * queueing the work. Also, since the scan abort waits for SCAN_HW
309 * to clear, we need to set SCAN_COMPLETE before clearing SCAN_HW
310 * to avoid a race there.
311 */
312 set_bit(STATUS_SCAN_COMPLETE, &priv->status);
313 clear_bit(STATUS_SCAN_HW, &priv->status);
314 queue_work(priv->workqueue, &priv->scan_completed);
315
316 if (priv->iw_mode != NL80211_IFTYPE_ADHOC &&
317 iwl_advanced_bt_coexist(priv) &&
318 priv->bt_status != scan_notif->bt_status) {
319 if (scan_notif->bt_status) {
320 /* BT on */
321 if (!priv->bt_ch_announce)
322 priv->bt_traffic_load =
323 IWL_BT_COEX_TRAFFIC_LOAD_HIGH;
324 /*
325 * otherwise, no traffic load information provided
326 * no changes made
327 */
328 } else {
329 /* BT off */
330 priv->bt_traffic_load =
331 IWL_BT_COEX_TRAFFIC_LOAD_NONE;
332 }
333 priv->bt_status = scan_notif->bt_status;
334 queue_work(priv->workqueue,
335 &priv->bt_traffic_change_work);
336 }
337 }
338
iwl_setup_rx_scan_handlers(struct iwl_priv * priv)339 void iwl_setup_rx_scan_handlers(struct iwl_priv *priv)
340 {
341 /* scan handlers */
342 priv->rx_handlers[REPLY_SCAN_CMD] = iwl_rx_reply_scan;
343 priv->rx_handlers[SCAN_START_NOTIFICATION] = iwl_rx_scan_start_notif;
344 priv->rx_handlers[SCAN_RESULTS_NOTIFICATION] =
345 iwl_rx_scan_results_notif;
346 priv->rx_handlers[SCAN_COMPLETE_NOTIFICATION] =
347 iwl_rx_scan_complete_notif;
348 }
349
iwl_get_active_dwell_time(struct iwl_priv * priv,enum nl80211_band band,u8 n_probes)350 static u16 iwl_get_active_dwell_time(struct iwl_priv *priv,
351 enum nl80211_band band, u8 n_probes)
352 {
353 if (band == NL80211_BAND_5GHZ)
354 return IWL_ACTIVE_DWELL_TIME_52 +
355 IWL_ACTIVE_DWELL_FACTOR_52GHZ * (n_probes + 1);
356 else
357 return IWL_ACTIVE_DWELL_TIME_24 +
358 IWL_ACTIVE_DWELL_FACTOR_24GHZ * (n_probes + 1);
359 }
360
iwl_limit_dwell(struct iwl_priv * priv,u16 dwell_time)361 static u16 iwl_limit_dwell(struct iwl_priv *priv, u16 dwell_time)
362 {
363 struct iwl_rxon_context *ctx;
364 int limits[NUM_IWL_RXON_CTX] = {};
365 int n_active = 0;
366 u16 limit;
367
368 BUILD_BUG_ON(NUM_IWL_RXON_CTX != 2);
369
370 /*
371 * If we're associated, we clamp the dwell time 98%
372 * of the beacon interval (minus 2 * channel tune time)
373 * If both contexts are active, we have to restrict to
374 * 1/2 of the minimum of them, because they might be in
375 * lock-step with the time inbetween only half of what
376 * time we'd have in each of them.
377 */
378 for_each_context(priv, ctx) {
379 switch (ctx->staging.dev_type) {
380 case RXON_DEV_TYPE_P2P:
381 /* no timing constraints */
382 continue;
383 case RXON_DEV_TYPE_ESS:
384 default:
385 /* timing constraints if associated */
386 if (!iwl_is_associated_ctx(ctx))
387 continue;
388 break;
389 case RXON_DEV_TYPE_CP:
390 case RXON_DEV_TYPE_2STA:
391 /*
392 * These seem to always have timers for TBTT
393 * active in uCode even when not associated yet.
394 */
395 break;
396 }
397
398 limits[n_active++] = ctx->beacon_int ?: IWL_PASSIVE_DWELL_BASE;
399 }
400
401 switch (n_active) {
402 case 0:
403 return dwell_time;
404 case 2:
405 limit = (limits[1] * 98) / 100 - IWL_CHANNEL_TUNE_TIME * 2;
406 limit /= 2;
407 dwell_time = min(limit, dwell_time);
408 fallthrough;
409 case 1:
410 limit = (limits[0] * 98) / 100 - IWL_CHANNEL_TUNE_TIME * 2;
411 limit /= n_active;
412 return min(limit, dwell_time);
413 default:
414 WARN_ON_ONCE(1);
415 return dwell_time;
416 }
417 }
418
iwl_get_passive_dwell_time(struct iwl_priv * priv,enum nl80211_band band)419 static u16 iwl_get_passive_dwell_time(struct iwl_priv *priv,
420 enum nl80211_band band)
421 {
422 u16 passive = (band == NL80211_BAND_2GHZ) ?
423 IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_24 :
424 IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_52;
425
426 return iwl_limit_dwell(priv, passive);
427 }
428
429 /* 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)430 static u8 iwl_get_single_channel_number(struct iwl_priv *priv,
431 enum nl80211_band band)
432 {
433 struct ieee80211_supported_band *sband = priv->hw->wiphy->bands[band];
434 struct iwl_rxon_context *ctx;
435 int i;
436
437 for (i = 0; i < sband->n_channels; i++) {
438 bool busy = false;
439
440 for_each_context(priv, ctx) {
441 busy = sband->channels[i].hw_value ==
442 le16_to_cpu(ctx->staging.channel);
443 if (busy)
444 break;
445 }
446
447 if (busy)
448 continue;
449
450 if (!(sband->channels[i].flags & IEEE80211_CHAN_DISABLED))
451 return sband->channels[i].hw_value;
452 }
453
454 return 0;
455 }
456
iwl_get_channel_for_reset_scan(struct iwl_priv * priv,struct ieee80211_vif * vif,enum nl80211_band band,struct iwl_scan_channel * scan_ch)457 static int iwl_get_channel_for_reset_scan(struct iwl_priv *priv,
458 struct ieee80211_vif *vif,
459 enum nl80211_band band,
460 struct iwl_scan_channel *scan_ch)
461 {
462 const struct ieee80211_supported_band *sband;
463 u16 channel;
464
465 sband = iwl_get_hw_mode(priv, band);
466 if (!sband) {
467 IWL_ERR(priv, "invalid band\n");
468 return 0;
469 }
470
471 channel = iwl_get_single_channel_number(priv, band);
472 if (channel) {
473 scan_ch->channel = cpu_to_le16(channel);
474 scan_ch->type = SCAN_CHANNEL_TYPE_PASSIVE;
475 scan_ch->active_dwell =
476 cpu_to_le16(IWL_RADIO_RESET_DWELL_TIME);
477 scan_ch->passive_dwell =
478 cpu_to_le16(IWL_RADIO_RESET_DWELL_TIME);
479 /* Set txpower levels to defaults */
480 scan_ch->dsp_atten = 110;
481 if (band == NL80211_BAND_5GHZ)
482 scan_ch->tx_gain = ((1 << 5) | (3 << 3)) | 3;
483 else
484 scan_ch->tx_gain = ((1 << 5) | (5 << 3));
485 return 1;
486 }
487
488 IWL_ERR(priv, "no valid channel found\n");
489 return 0;
490 }
491
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)492 static int iwl_get_channels_for_scan(struct iwl_priv *priv,
493 struct ieee80211_vif *vif,
494 enum nl80211_band band,
495 u8 is_active, u8 n_probes,
496 struct iwl_scan_channel *scan_ch)
497 {
498 struct ieee80211_channel *chan;
499 const struct ieee80211_supported_band *sband;
500 u16 passive_dwell = 0;
501 u16 active_dwell = 0;
502 int added, i;
503 u16 channel;
504
505 sband = iwl_get_hw_mode(priv, band);
506 if (!sband)
507 return 0;
508
509 active_dwell = iwl_get_active_dwell_time(priv, band, n_probes);
510 passive_dwell = iwl_get_passive_dwell_time(priv, band);
511
512 if (passive_dwell <= active_dwell)
513 passive_dwell = active_dwell + 1;
514
515 for (i = 0, added = 0; i < priv->scan_request->n_channels; i++) {
516 chan = priv->scan_request->channels[i];
517
518 if (chan->band != band)
519 continue;
520
521 channel = chan->hw_value;
522 scan_ch->channel = cpu_to_le16(channel);
523
524 if (!is_active || (chan->flags & IEEE80211_CHAN_NO_IR))
525 scan_ch->type = SCAN_CHANNEL_TYPE_PASSIVE;
526 else
527 scan_ch->type = SCAN_CHANNEL_TYPE_ACTIVE;
528
529 if (n_probes)
530 scan_ch->type |= IWL_SCAN_PROBE_MASK(n_probes);
531
532 scan_ch->active_dwell = cpu_to_le16(active_dwell);
533 scan_ch->passive_dwell = cpu_to_le16(passive_dwell);
534
535 /* Set txpower levels to defaults */
536 scan_ch->dsp_atten = 110;
537
538 /* NOTE: if we were doing 6Mb OFDM for scans we'd use
539 * power level:
540 * scan_ch->tx_gain = ((1 << 5) | (2 << 3)) | 3;
541 */
542 if (band == NL80211_BAND_5GHZ)
543 scan_ch->tx_gain = ((1 << 5) | (3 << 3)) | 3;
544 else
545 scan_ch->tx_gain = ((1 << 5) | (5 << 3));
546
547 IWL_DEBUG_SCAN(priv, "Scanning ch=%d prob=0x%X [%s %d]\n",
548 channel, le32_to_cpu(scan_ch->type),
549 (scan_ch->type & SCAN_CHANNEL_TYPE_ACTIVE) ?
550 "ACTIVE" : "PASSIVE",
551 (scan_ch->type & SCAN_CHANNEL_TYPE_ACTIVE) ?
552 active_dwell : passive_dwell);
553
554 scan_ch++;
555 added++;
556 }
557
558 IWL_DEBUG_SCAN(priv, "total channels to scan %d\n", added);
559 return added;
560 }
561
562 /*
563 * iwl_fill_probe_req - fill in all required fields and IE for probe request
564 */
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)565 static u16 iwl_fill_probe_req(struct ieee80211_mgmt *frame, const u8 *ta,
566 const u8 *ies, int ie_len, const u8 *ssid,
567 u8 ssid_len, int left)
568 {
569 int len = 0;
570 u8 *pos = NULL;
571
572 /* Make sure there is enough space for the probe request,
573 * two mandatory IEs and the data */
574 left -= 24;
575 if (left < 0)
576 return 0;
577
578 frame->frame_control = cpu_to_le16(IEEE80211_STYPE_PROBE_REQ);
579 eth_broadcast_addr(frame->da);
580 memcpy(frame->sa, ta, ETH_ALEN);
581 eth_broadcast_addr(frame->bssid);
582 frame->seq_ctrl = 0;
583
584 len += 24;
585
586 /* ...next IE... */
587 pos = &frame->u.probe_req.variable[0];
588
589 /* fill in our SSID IE */
590 left -= ssid_len + 2;
591 if (left < 0)
592 return 0;
593 *pos++ = WLAN_EID_SSID;
594 *pos++ = ssid_len;
595 if (ssid && ssid_len) {
596 memcpy(pos, ssid, ssid_len);
597 pos += ssid_len;
598 }
599
600 len += ssid_len + 2;
601
602 if (WARN_ON(left < ie_len))
603 return len;
604
605 if (ies && ie_len) {
606 memcpy(pos, ies, ie_len);
607 len += ie_len;
608 }
609
610 return (u16)len;
611 }
612
iwlagn_request_scan(struct iwl_priv * priv,struct ieee80211_vif * vif)613 static int iwlagn_request_scan(struct iwl_priv *priv, struct ieee80211_vif *vif)
614 {
615 struct iwl_host_cmd cmd = {
616 .id = REPLY_SCAN_CMD,
617 .len = { sizeof(struct iwl_scan_cmd), },
618 };
619 struct iwl_scan_cmd *scan;
620 struct iwl_rxon_context *ctx = &priv->contexts[IWL_RXON_CTX_BSS];
621 u32 rate_flags = 0;
622 u16 cmd_len = 0;
623 u16 rx_chain = 0;
624 enum nl80211_band band;
625 u8 n_probes = 0;
626 u8 rx_ant = priv->nvm_data->valid_rx_ant;
627 u8 rate;
628 bool is_active = false;
629 int chan_mod;
630 u8 active_chains;
631 u8 scan_tx_antennas = priv->nvm_data->valid_tx_ant;
632 int ret;
633 int scan_cmd_size = sizeof(struct iwl_scan_cmd) +
634 MAX_SCAN_CHANNEL * sizeof(struct iwl_scan_channel) +
635 priv->fw->ucode_capa.max_probe_length;
636 const u8 *ssid = NULL;
637 u8 ssid_len = 0;
638
639 if (WARN_ON(priv->scan_type == IWL_SCAN_NORMAL &&
640 (!priv->scan_request ||
641 priv->scan_request->n_channels > MAX_SCAN_CHANNEL)))
642 return -EINVAL;
643
644 lockdep_assert_held(&priv->mutex);
645
646 if (vif)
647 ctx = iwl_rxon_ctx_from_vif(vif);
648
649 if (!priv->scan_cmd) {
650 priv->scan_cmd = kmalloc(scan_cmd_size, GFP_KERNEL);
651 if (!priv->scan_cmd) {
652 IWL_DEBUG_SCAN(priv,
653 "fail to allocate memory for scan\n");
654 return -ENOMEM;
655 }
656 }
657 scan = priv->scan_cmd;
658 memset(scan, 0, scan_cmd_size);
659
660 scan->quiet_plcp_th = IWL_PLCP_QUIET_THRESH;
661 scan->quiet_time = IWL_ACTIVE_QUIET_TIME;
662
663 if (iwl_is_any_associated(priv)) {
664 u16 interval = 0;
665 u32 extra;
666 u32 suspend_time = 100;
667 u32 scan_suspend_time = 100;
668
669 IWL_DEBUG_INFO(priv, "Scanning while associated...\n");
670 switch (priv->scan_type) {
671 case IWL_SCAN_RADIO_RESET:
672 interval = 0;
673 break;
674 case IWL_SCAN_NORMAL:
675 interval = vif->bss_conf.beacon_int;
676 break;
677 }
678
679 scan->suspend_time = 0;
680 scan->max_out_time = cpu_to_le32(200 * 1024);
681 if (!interval)
682 interval = suspend_time;
683
684 extra = (suspend_time / interval) << 22;
685 scan_suspend_time = (extra |
686 ((suspend_time % interval) * 1024));
687 scan->suspend_time = cpu_to_le32(scan_suspend_time);
688 IWL_DEBUG_SCAN(priv, "suspend_time 0x%X beacon interval %d\n",
689 scan_suspend_time, interval);
690 }
691
692 switch (priv->scan_type) {
693 case IWL_SCAN_RADIO_RESET:
694 IWL_DEBUG_SCAN(priv, "Start internal passive scan.\n");
695 /*
696 * Override quiet time as firmware checks that active
697 * dwell is >= quiet; since we use passive scan it'll
698 * not actually be used.
699 */
700 scan->quiet_time = cpu_to_le16(IWL_RADIO_RESET_DWELL_TIME);
701 break;
702 case IWL_SCAN_NORMAL:
703 if (priv->scan_request->n_ssids) {
704 int i, p = 0;
705 IWL_DEBUG_SCAN(priv, "Kicking off active scan\n");
706 /*
707 * The highest priority SSID is inserted to the
708 * probe request template.
709 */
710 ssid_len = priv->scan_request->ssids[0].ssid_len;
711 ssid = priv->scan_request->ssids[0].ssid;
712
713 /*
714 * Invert the order of ssids, the firmware will invert
715 * it back.
716 */
717 for (i = priv->scan_request->n_ssids - 1; i >= 1; i--) {
718 scan->direct_scan[p].id = WLAN_EID_SSID;
719 scan->direct_scan[p].len =
720 priv->scan_request->ssids[i].ssid_len;
721 memcpy(scan->direct_scan[p].ssid,
722 priv->scan_request->ssids[i].ssid,
723 priv->scan_request->ssids[i].ssid_len);
724 n_probes++;
725 p++;
726 }
727 is_active = true;
728 } else
729 IWL_DEBUG_SCAN(priv, "Start passive scan.\n");
730 break;
731 }
732
733 scan->tx_cmd.tx_flags = TX_CMD_FLG_SEQ_CTL_MSK;
734 scan->tx_cmd.sta_id = ctx->bcast_sta_id;
735 scan->tx_cmd.stop_time.life_time = TX_CMD_LIFE_TIME_INFINITE;
736
737 switch (priv->scan_band) {
738 case NL80211_BAND_2GHZ:
739 scan->flags = RXON_FLG_BAND_24G_MSK | RXON_FLG_AUTO_DETECT_MSK;
740 chan_mod = le32_to_cpu(
741 priv->contexts[IWL_RXON_CTX_BSS].active.flags &
742 RXON_FLG_CHANNEL_MODE_MSK)
743 >> RXON_FLG_CHANNEL_MODE_POS;
744 if ((priv->scan_request && priv->scan_request->no_cck) ||
745 chan_mod == CHANNEL_MODE_PURE_40) {
746 rate = IWL_RATE_6M_PLCP;
747 } else {
748 rate = IWL_RATE_1M_PLCP;
749 rate_flags = RATE_MCS_CCK_MSK;
750 }
751 /*
752 * Internal scans are passive, so we can indiscriminately set
753 * the BT ignore flag on 2.4 GHz since it applies to TX only.
754 */
755 if (priv->lib->bt_params &&
756 priv->lib->bt_params->advanced_bt_coexist)
757 scan->tx_cmd.tx_flags |= TX_CMD_FLG_IGNORE_BT;
758 break;
759 case NL80211_BAND_5GHZ:
760 rate = IWL_RATE_6M_PLCP;
761 break;
762 default:
763 IWL_WARN(priv, "Invalid scan band\n");
764 return -EIO;
765 }
766
767 /*
768 * If active scanning is requested but a certain channel is
769 * marked passive, we can do active scanning if we detect
770 * transmissions.
771 *
772 * There is an issue with some firmware versions that triggers
773 * a sysassert on a "good CRC threshold" of zero (== disabled),
774 * on a radar channel even though this means that we should NOT
775 * send probes.
776 *
777 * The "good CRC threshold" is the number of frames that we
778 * need to receive during our dwell time on a channel before
779 * sending out probes -- setting this to a huge value will
780 * mean we never reach it, but at the same time work around
781 * the aforementioned issue. Thus use IWL_GOOD_CRC_TH_NEVER
782 * here instead of IWL_GOOD_CRC_TH_DISABLED.
783 *
784 * This was fixed in later versions along with some other
785 * scan changes, and the threshold behaves as a flag in those
786 * versions.
787 */
788 if (priv->new_scan_threshold_behaviour)
789 scan->good_CRC_th = is_active ? IWL_GOOD_CRC_TH_DEFAULT :
790 IWL_GOOD_CRC_TH_DISABLED;
791 else
792 scan->good_CRC_th = is_active ? IWL_GOOD_CRC_TH_DEFAULT :
793 IWL_GOOD_CRC_TH_NEVER;
794
795 band = priv->scan_band;
796
797 if (band == NL80211_BAND_2GHZ &&
798 priv->lib->bt_params &&
799 priv->lib->bt_params->advanced_bt_coexist) {
800 /* transmit 2.4 GHz probes only on first antenna */
801 scan_tx_antennas = first_antenna(scan_tx_antennas);
802 }
803
804 priv->scan_tx_ant[band] = iwl_toggle_tx_ant(priv,
805 priv->scan_tx_ant[band],
806 scan_tx_antennas);
807 rate_flags |= iwl_ant_idx_to_flags(priv->scan_tx_ant[band]);
808 scan->tx_cmd.rate_n_flags = iwl_hw_set_rate_n_flags(rate, rate_flags);
809
810 /*
811 * In power save mode while associated use one chain,
812 * otherwise use all chains
813 */
814 if (test_bit(STATUS_POWER_PMI, &priv->status) &&
815 !(priv->hw->conf.flags & IEEE80211_CONF_IDLE)) {
816 /* rx_ant has been set to all valid chains previously */
817 active_chains = rx_ant &
818 ((u8)(priv->chain_noise_data.active_chains));
819 if (!active_chains)
820 active_chains = rx_ant;
821
822 IWL_DEBUG_SCAN(priv, "chain_noise_data.active_chains: %u\n",
823 priv->chain_noise_data.active_chains);
824
825 rx_ant = first_antenna(active_chains);
826 }
827 if (priv->lib->bt_params &&
828 priv->lib->bt_params->advanced_bt_coexist &&
829 priv->bt_full_concurrent) {
830 /* operated as 1x1 in full concurrency mode */
831 rx_ant = first_antenna(rx_ant);
832 }
833
834 /* MIMO is not used here, but value is required */
835 rx_chain |=
836 priv->nvm_data->valid_rx_ant << RXON_RX_CHAIN_VALID_POS;
837 rx_chain |= rx_ant << RXON_RX_CHAIN_FORCE_MIMO_SEL_POS;
838 rx_chain |= rx_ant << RXON_RX_CHAIN_FORCE_SEL_POS;
839 rx_chain |= 0x1 << RXON_RX_CHAIN_DRIVER_FORCE_POS;
840 scan->rx_chain = cpu_to_le16(rx_chain);
841 switch (priv->scan_type) {
842 case IWL_SCAN_NORMAL:
843 cmd_len = iwl_fill_probe_req(
844 (struct ieee80211_mgmt *)scan->data,
845 vif->addr,
846 priv->scan_request->ie,
847 priv->scan_request->ie_len,
848 ssid, ssid_len,
849 scan_cmd_size - sizeof(*scan));
850 break;
851 case IWL_SCAN_RADIO_RESET:
852 /* use bcast addr, will not be transmitted but must be valid */
853 cmd_len = iwl_fill_probe_req(
854 (struct ieee80211_mgmt *)scan->data,
855 iwl_bcast_addr, NULL, 0,
856 NULL, 0,
857 scan_cmd_size - sizeof(*scan));
858 break;
859 default:
860 BUG();
861 }
862 scan->tx_cmd.len = cpu_to_le16(cmd_len);
863
864 scan->filter_flags |= (RXON_FILTER_ACCEPT_GRP_MSK |
865 RXON_FILTER_BCON_AWARE_MSK);
866
867 switch (priv->scan_type) {
868 case IWL_SCAN_RADIO_RESET:
869 scan->channel_count =
870 iwl_get_channel_for_reset_scan(priv, vif, band,
871 (void *)&scan->data[cmd_len]);
872 break;
873 case IWL_SCAN_NORMAL:
874 scan->channel_count =
875 iwl_get_channels_for_scan(priv, vif, band,
876 is_active, n_probes,
877 (void *)&scan->data[cmd_len]);
878 break;
879 }
880
881 if (scan->channel_count == 0) {
882 IWL_DEBUG_SCAN(priv, "channel count %d\n", scan->channel_count);
883 return -EIO;
884 }
885
886 cmd.len[0] += le16_to_cpu(scan->tx_cmd.len) +
887 scan->channel_count * sizeof(struct iwl_scan_channel);
888 cmd.data[0] = scan;
889 cmd.dataflags[0] = IWL_HCMD_DFL_NOCOPY;
890 scan->len = cpu_to_le16(cmd.len[0]);
891
892 /* set scan bit here for PAN params */
893 set_bit(STATUS_SCAN_HW, &priv->status);
894
895 ret = iwlagn_set_pan_params(priv);
896 if (ret) {
897 clear_bit(STATUS_SCAN_HW, &priv->status);
898 return ret;
899 }
900
901 ret = iwl_dvm_send_cmd(priv, &cmd);
902 if (ret) {
903 clear_bit(STATUS_SCAN_HW, &priv->status);
904 iwlagn_set_pan_params(priv);
905 }
906
907 return ret;
908 }
909
iwl_init_scan_params(struct iwl_priv * priv)910 void iwl_init_scan_params(struct iwl_priv *priv)
911 {
912 u8 ant_idx = fls(priv->nvm_data->valid_tx_ant) - 1;
913 if (!priv->scan_tx_ant[NL80211_BAND_5GHZ])
914 priv->scan_tx_ant[NL80211_BAND_5GHZ] = ant_idx;
915 if (!priv->scan_tx_ant[NL80211_BAND_2GHZ])
916 priv->scan_tx_ant[NL80211_BAND_2GHZ] = ant_idx;
917 }
918
iwl_scan_initiate(struct iwl_priv * priv,struct ieee80211_vif * vif,enum iwl_scan_type scan_type,enum nl80211_band band)919 int __must_check iwl_scan_initiate(struct iwl_priv *priv,
920 struct ieee80211_vif *vif,
921 enum iwl_scan_type scan_type,
922 enum nl80211_band band)
923 {
924 int ret;
925
926 lockdep_assert_held(&priv->mutex);
927
928 cancel_delayed_work(&priv->scan_check);
929
930 if (!iwl_is_ready_rf(priv)) {
931 IWL_WARN(priv, "Request scan called when driver not ready.\n");
932 return -EIO;
933 }
934
935 if (test_bit(STATUS_SCAN_HW, &priv->status)) {
936 IWL_DEBUG_SCAN(priv,
937 "Multiple concurrent scan requests in parallel.\n");
938 return -EBUSY;
939 }
940
941 if (test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
942 IWL_DEBUG_SCAN(priv, "Scan request while abort pending.\n");
943 return -EBUSY;
944 }
945
946 IWL_DEBUG_SCAN(priv, "Starting %sscan...\n",
947 scan_type == IWL_SCAN_NORMAL ? "" :
948 "internal short ");
949
950 set_bit(STATUS_SCANNING, &priv->status);
951 priv->scan_type = scan_type;
952 priv->scan_start = jiffies;
953 priv->scan_band = band;
954
955 ret = iwlagn_request_scan(priv, vif);
956 if (ret) {
957 clear_bit(STATUS_SCANNING, &priv->status);
958 priv->scan_type = IWL_SCAN_NORMAL;
959 return ret;
960 }
961
962 queue_delayed_work(priv->workqueue, &priv->scan_check,
963 IWL_SCAN_CHECK_WATCHDOG);
964
965 return 0;
966 }
967
968
969 /*
970 * internal short scan, this function should only been called while associated.
971 * It will reset and tune the radio to prevent possible RF related problem
972 */
iwl_internal_short_hw_scan(struct iwl_priv * priv)973 void iwl_internal_short_hw_scan(struct iwl_priv *priv)
974 {
975 queue_work(priv->workqueue, &priv->start_internal_scan);
976 }
977
iwl_bg_start_internal_scan(struct work_struct * work)978 static void iwl_bg_start_internal_scan(struct work_struct *work)
979 {
980 struct iwl_priv *priv =
981 container_of(work, struct iwl_priv, start_internal_scan);
982
983 IWL_DEBUG_SCAN(priv, "Start internal scan\n");
984
985 mutex_lock(&priv->mutex);
986
987 if (priv->scan_type == IWL_SCAN_RADIO_RESET) {
988 IWL_DEBUG_SCAN(priv, "Internal scan already in progress\n");
989 goto unlock;
990 }
991
992 if (test_bit(STATUS_SCANNING, &priv->status)) {
993 IWL_DEBUG_SCAN(priv, "Scan already in progress.\n");
994 goto unlock;
995 }
996
997 if (iwl_scan_initiate(priv, NULL, IWL_SCAN_RADIO_RESET, priv->band))
998 IWL_DEBUG_SCAN(priv, "failed to start internal short scan\n");
999 unlock:
1000 mutex_unlock(&priv->mutex);
1001 }
1002
iwl_bg_scan_check(struct work_struct * data)1003 static void iwl_bg_scan_check(struct work_struct *data)
1004 {
1005 struct iwl_priv *priv =
1006 container_of(data, struct iwl_priv, scan_check.work);
1007
1008 IWL_DEBUG_SCAN(priv, "Scan check work\n");
1009
1010 /* Since we are here firmware does not finish scan and
1011 * most likely is in bad shape, so we don't bother to
1012 * send abort command, just force scan complete to mac80211 */
1013 mutex_lock(&priv->mutex);
1014 iwl_force_scan_end(priv);
1015 mutex_unlock(&priv->mutex);
1016 }
1017
iwl_bg_abort_scan(struct work_struct * work)1018 static void iwl_bg_abort_scan(struct work_struct *work)
1019 {
1020 struct iwl_priv *priv = container_of(work, struct iwl_priv, abort_scan);
1021
1022 IWL_DEBUG_SCAN(priv, "Abort scan work\n");
1023
1024 /* We keep scan_check work queued in case when firmware will not
1025 * report back scan completed notification */
1026 mutex_lock(&priv->mutex);
1027 iwl_scan_cancel_timeout(priv, 200);
1028 mutex_unlock(&priv->mutex);
1029 }
1030
iwl_bg_scan_completed(struct work_struct * work)1031 static void iwl_bg_scan_completed(struct work_struct *work)
1032 {
1033 struct iwl_priv *priv =
1034 container_of(work, struct iwl_priv, scan_completed);
1035
1036 mutex_lock(&priv->mutex);
1037 iwl_process_scan_complete(priv);
1038 mutex_unlock(&priv->mutex);
1039 }
1040
iwl_setup_scan_deferred_work(struct iwl_priv * priv)1041 void iwl_setup_scan_deferred_work(struct iwl_priv *priv)
1042 {
1043 INIT_WORK(&priv->scan_completed, iwl_bg_scan_completed);
1044 INIT_WORK(&priv->abort_scan, iwl_bg_abort_scan);
1045 INIT_WORK(&priv->start_internal_scan, iwl_bg_start_internal_scan);
1046 INIT_DELAYED_WORK(&priv->scan_check, iwl_bg_scan_check);
1047 }
1048
iwl_cancel_scan_deferred_work(struct iwl_priv * priv)1049 void iwl_cancel_scan_deferred_work(struct iwl_priv *priv)
1050 {
1051 cancel_work_sync(&priv->start_internal_scan);
1052 cancel_work_sync(&priv->abort_scan);
1053 cancel_work_sync(&priv->scan_completed);
1054
1055 if (cancel_delayed_work_sync(&priv->scan_check)) {
1056 mutex_lock(&priv->mutex);
1057 iwl_force_scan_end(priv);
1058 mutex_unlock(&priv->mutex);
1059 }
1060 }
1061