xref: /openbmc/linux/net/wireless/chan.c (revision 4f6cce39)
1 /*
2  * This file contains helper code to handle channel
3  * settings and keeping track of what is possible at
4  * any point in time.
5  *
6  * Copyright 2009	Johannes Berg <johannes@sipsolutions.net>
7  * Copyright 2013-2014  Intel Mobile Communications GmbH
8  */
9 
10 #include <linux/export.h>
11 #include <net/cfg80211.h>
12 #include "core.h"
13 #include "rdev-ops.h"
14 
15 void cfg80211_chandef_create(struct cfg80211_chan_def *chandef,
16 			     struct ieee80211_channel *chan,
17 			     enum nl80211_channel_type chan_type)
18 {
19 	if (WARN_ON(!chan))
20 		return;
21 
22 	chandef->chan = chan;
23 	chandef->center_freq2 = 0;
24 
25 	switch (chan_type) {
26 	case NL80211_CHAN_NO_HT:
27 		chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
28 		chandef->center_freq1 = chan->center_freq;
29 		break;
30 	case NL80211_CHAN_HT20:
31 		chandef->width = NL80211_CHAN_WIDTH_20;
32 		chandef->center_freq1 = chan->center_freq;
33 		break;
34 	case NL80211_CHAN_HT40PLUS:
35 		chandef->width = NL80211_CHAN_WIDTH_40;
36 		chandef->center_freq1 = chan->center_freq + 10;
37 		break;
38 	case NL80211_CHAN_HT40MINUS:
39 		chandef->width = NL80211_CHAN_WIDTH_40;
40 		chandef->center_freq1 = chan->center_freq - 10;
41 		break;
42 	default:
43 		WARN_ON(1);
44 	}
45 }
46 EXPORT_SYMBOL(cfg80211_chandef_create);
47 
48 bool cfg80211_chandef_valid(const struct cfg80211_chan_def *chandef)
49 {
50 	u32 control_freq;
51 
52 	if (!chandef->chan)
53 		return false;
54 
55 	control_freq = chandef->chan->center_freq;
56 
57 	switch (chandef->width) {
58 	case NL80211_CHAN_WIDTH_5:
59 	case NL80211_CHAN_WIDTH_10:
60 	case NL80211_CHAN_WIDTH_20:
61 	case NL80211_CHAN_WIDTH_20_NOHT:
62 		if (chandef->center_freq1 != control_freq)
63 			return false;
64 		if (chandef->center_freq2)
65 			return false;
66 		break;
67 	case NL80211_CHAN_WIDTH_40:
68 		if (chandef->center_freq1 != control_freq + 10 &&
69 		    chandef->center_freq1 != control_freq - 10)
70 			return false;
71 		if (chandef->center_freq2)
72 			return false;
73 		break;
74 	case NL80211_CHAN_WIDTH_80P80:
75 		if (chandef->center_freq1 != control_freq + 30 &&
76 		    chandef->center_freq1 != control_freq + 10 &&
77 		    chandef->center_freq1 != control_freq - 10 &&
78 		    chandef->center_freq1 != control_freq - 30)
79 			return false;
80 		if (!chandef->center_freq2)
81 			return false;
82 		/* adjacent is not allowed -- that's a 160 MHz channel */
83 		if (chandef->center_freq1 - chandef->center_freq2 == 80 ||
84 		    chandef->center_freq2 - chandef->center_freq1 == 80)
85 			return false;
86 		break;
87 	case NL80211_CHAN_WIDTH_80:
88 		if (chandef->center_freq1 != control_freq + 30 &&
89 		    chandef->center_freq1 != control_freq + 10 &&
90 		    chandef->center_freq1 != control_freq - 10 &&
91 		    chandef->center_freq1 != control_freq - 30)
92 			return false;
93 		if (chandef->center_freq2)
94 			return false;
95 		break;
96 	case NL80211_CHAN_WIDTH_160:
97 		if (chandef->center_freq1 != control_freq + 70 &&
98 		    chandef->center_freq1 != control_freq + 50 &&
99 		    chandef->center_freq1 != control_freq + 30 &&
100 		    chandef->center_freq1 != control_freq + 10 &&
101 		    chandef->center_freq1 != control_freq - 10 &&
102 		    chandef->center_freq1 != control_freq - 30 &&
103 		    chandef->center_freq1 != control_freq - 50 &&
104 		    chandef->center_freq1 != control_freq - 70)
105 			return false;
106 		if (chandef->center_freq2)
107 			return false;
108 		break;
109 	default:
110 		return false;
111 	}
112 
113 	return true;
114 }
115 EXPORT_SYMBOL(cfg80211_chandef_valid);
116 
117 static void chandef_primary_freqs(const struct cfg80211_chan_def *c,
118 				  u32 *pri40, u32 *pri80)
119 {
120 	int tmp;
121 
122 	switch (c->width) {
123 	case NL80211_CHAN_WIDTH_40:
124 		*pri40 = c->center_freq1;
125 		*pri80 = 0;
126 		break;
127 	case NL80211_CHAN_WIDTH_80:
128 	case NL80211_CHAN_WIDTH_80P80:
129 		*pri80 = c->center_freq1;
130 		/* n_P20 */
131 		tmp = (30 + c->chan->center_freq - c->center_freq1)/20;
132 		/* n_P40 */
133 		tmp /= 2;
134 		/* freq_P40 */
135 		*pri40 = c->center_freq1 - 20 + 40 * tmp;
136 		break;
137 	case NL80211_CHAN_WIDTH_160:
138 		/* n_P20 */
139 		tmp = (70 + c->chan->center_freq - c->center_freq1)/20;
140 		/* n_P40 */
141 		tmp /= 2;
142 		/* freq_P40 */
143 		*pri40 = c->center_freq1 - 60 + 40 * tmp;
144 		/* n_P80 */
145 		tmp /= 2;
146 		*pri80 = c->center_freq1 - 40 + 80 * tmp;
147 		break;
148 	default:
149 		WARN_ON_ONCE(1);
150 	}
151 }
152 
153 static int cfg80211_chandef_get_width(const struct cfg80211_chan_def *c)
154 {
155 	int width;
156 
157 	switch (c->width) {
158 	case NL80211_CHAN_WIDTH_5:
159 		width = 5;
160 		break;
161 	case NL80211_CHAN_WIDTH_10:
162 		width = 10;
163 		break;
164 	case NL80211_CHAN_WIDTH_20:
165 	case NL80211_CHAN_WIDTH_20_NOHT:
166 		width = 20;
167 		break;
168 	case NL80211_CHAN_WIDTH_40:
169 		width = 40;
170 		break;
171 	case NL80211_CHAN_WIDTH_80P80:
172 	case NL80211_CHAN_WIDTH_80:
173 		width = 80;
174 		break;
175 	case NL80211_CHAN_WIDTH_160:
176 		width = 160;
177 		break;
178 	default:
179 		WARN_ON_ONCE(1);
180 		return -1;
181 	}
182 	return width;
183 }
184 
185 const struct cfg80211_chan_def *
186 cfg80211_chandef_compatible(const struct cfg80211_chan_def *c1,
187 			    const struct cfg80211_chan_def *c2)
188 {
189 	u32 c1_pri40, c1_pri80, c2_pri40, c2_pri80;
190 
191 	/* If they are identical, return */
192 	if (cfg80211_chandef_identical(c1, c2))
193 		return c1;
194 
195 	/* otherwise, must have same control channel */
196 	if (c1->chan != c2->chan)
197 		return NULL;
198 
199 	/*
200 	 * If they have the same width, but aren't identical,
201 	 * then they can't be compatible.
202 	 */
203 	if (c1->width == c2->width)
204 		return NULL;
205 
206 	/*
207 	 * can't be compatible if one of them is 5 or 10 MHz,
208 	 * but they don't have the same width.
209 	 */
210 	if (c1->width == NL80211_CHAN_WIDTH_5 ||
211 	    c1->width == NL80211_CHAN_WIDTH_10 ||
212 	    c2->width == NL80211_CHAN_WIDTH_5 ||
213 	    c2->width == NL80211_CHAN_WIDTH_10)
214 		return NULL;
215 
216 	if (c1->width == NL80211_CHAN_WIDTH_20_NOHT ||
217 	    c1->width == NL80211_CHAN_WIDTH_20)
218 		return c2;
219 
220 	if (c2->width == NL80211_CHAN_WIDTH_20_NOHT ||
221 	    c2->width == NL80211_CHAN_WIDTH_20)
222 		return c1;
223 
224 	chandef_primary_freqs(c1, &c1_pri40, &c1_pri80);
225 	chandef_primary_freqs(c2, &c2_pri40, &c2_pri80);
226 
227 	if (c1_pri40 != c2_pri40)
228 		return NULL;
229 
230 	WARN_ON(!c1_pri80 && !c2_pri80);
231 	if (c1_pri80 && c2_pri80 && c1_pri80 != c2_pri80)
232 		return NULL;
233 
234 	if (c1->width > c2->width)
235 		return c1;
236 	return c2;
237 }
238 EXPORT_SYMBOL(cfg80211_chandef_compatible);
239 
240 static void cfg80211_set_chans_dfs_state(struct wiphy *wiphy, u32 center_freq,
241 					 u32 bandwidth,
242 					 enum nl80211_dfs_state dfs_state)
243 {
244 	struct ieee80211_channel *c;
245 	u32 freq;
246 
247 	for (freq = center_freq - bandwidth/2 + 10;
248 	     freq <= center_freq + bandwidth/2 - 10;
249 	     freq += 20) {
250 		c = ieee80211_get_channel(wiphy, freq);
251 		if (!c || !(c->flags & IEEE80211_CHAN_RADAR))
252 			continue;
253 
254 		c->dfs_state = dfs_state;
255 		c->dfs_state_entered = jiffies;
256 	}
257 }
258 
259 void cfg80211_set_dfs_state(struct wiphy *wiphy,
260 			    const struct cfg80211_chan_def *chandef,
261 			    enum nl80211_dfs_state dfs_state)
262 {
263 	int width;
264 
265 	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
266 		return;
267 
268 	width = cfg80211_chandef_get_width(chandef);
269 	if (width < 0)
270 		return;
271 
272 	cfg80211_set_chans_dfs_state(wiphy, chandef->center_freq1,
273 				     width, dfs_state);
274 
275 	if (!chandef->center_freq2)
276 		return;
277 	cfg80211_set_chans_dfs_state(wiphy, chandef->center_freq2,
278 				     width, dfs_state);
279 }
280 
281 static u32 cfg80211_get_start_freq(u32 center_freq,
282 				   u32 bandwidth)
283 {
284 	u32 start_freq;
285 
286 	if (bandwidth <= 20)
287 		start_freq = center_freq;
288 	else
289 		start_freq = center_freq - bandwidth/2 + 10;
290 
291 	return start_freq;
292 }
293 
294 static u32 cfg80211_get_end_freq(u32 center_freq,
295 				 u32 bandwidth)
296 {
297 	u32 end_freq;
298 
299 	if (bandwidth <= 20)
300 		end_freq = center_freq;
301 	else
302 		end_freq = center_freq + bandwidth/2 - 10;
303 
304 	return end_freq;
305 }
306 
307 static int cfg80211_get_chans_dfs_required(struct wiphy *wiphy,
308 					    u32 center_freq,
309 					    u32 bandwidth)
310 {
311 	struct ieee80211_channel *c;
312 	u32 freq, start_freq, end_freq;
313 
314 	start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
315 	end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
316 
317 	for (freq = start_freq; freq <= end_freq; freq += 20) {
318 		c = ieee80211_get_channel(wiphy, freq);
319 		if (!c)
320 			return -EINVAL;
321 
322 		if (c->flags & IEEE80211_CHAN_RADAR)
323 			return 1;
324 	}
325 	return 0;
326 }
327 
328 
329 int cfg80211_chandef_dfs_required(struct wiphy *wiphy,
330 				  const struct cfg80211_chan_def *chandef,
331 				  enum nl80211_iftype iftype)
332 {
333 	int width;
334 	int ret;
335 
336 	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
337 		return -EINVAL;
338 
339 	switch (iftype) {
340 	case NL80211_IFTYPE_ADHOC:
341 	case NL80211_IFTYPE_AP:
342 	case NL80211_IFTYPE_P2P_GO:
343 	case NL80211_IFTYPE_MESH_POINT:
344 		width = cfg80211_chandef_get_width(chandef);
345 		if (width < 0)
346 			return -EINVAL;
347 
348 		ret = cfg80211_get_chans_dfs_required(wiphy,
349 						      chandef->center_freq1,
350 						      width);
351 		if (ret < 0)
352 			return ret;
353 		else if (ret > 0)
354 			return BIT(chandef->width);
355 
356 		if (!chandef->center_freq2)
357 			return 0;
358 
359 		ret = cfg80211_get_chans_dfs_required(wiphy,
360 						      chandef->center_freq2,
361 						      width);
362 		if (ret < 0)
363 			return ret;
364 		else if (ret > 0)
365 			return BIT(chandef->width);
366 
367 		break;
368 	case NL80211_IFTYPE_STATION:
369 	case NL80211_IFTYPE_OCB:
370 	case NL80211_IFTYPE_P2P_CLIENT:
371 	case NL80211_IFTYPE_MONITOR:
372 	case NL80211_IFTYPE_AP_VLAN:
373 	case NL80211_IFTYPE_WDS:
374 	case NL80211_IFTYPE_P2P_DEVICE:
375 	case NL80211_IFTYPE_NAN:
376 		break;
377 	case NL80211_IFTYPE_UNSPECIFIED:
378 	case NUM_NL80211_IFTYPES:
379 		WARN_ON(1);
380 	}
381 
382 	return 0;
383 }
384 EXPORT_SYMBOL(cfg80211_chandef_dfs_required);
385 
386 static int cfg80211_get_chans_dfs_usable(struct wiphy *wiphy,
387 					 u32 center_freq,
388 					 u32 bandwidth)
389 {
390 	struct ieee80211_channel *c;
391 	u32 freq, start_freq, end_freq;
392 	int count = 0;
393 
394 	start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
395 	end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
396 
397 	/*
398 	 * Check entire range of channels for the bandwidth.
399 	 * Check all channels are DFS channels (DFS_USABLE or
400 	 * DFS_AVAILABLE). Return number of usable channels
401 	 * (require CAC). Allow DFS and non-DFS channel mix.
402 	 */
403 	for (freq = start_freq; freq <= end_freq; freq += 20) {
404 		c = ieee80211_get_channel(wiphy, freq);
405 		if (!c)
406 			return -EINVAL;
407 
408 		if (c->flags & IEEE80211_CHAN_DISABLED)
409 			return -EINVAL;
410 
411 		if (c->flags & IEEE80211_CHAN_RADAR) {
412 			if (c->dfs_state == NL80211_DFS_UNAVAILABLE)
413 				return -EINVAL;
414 
415 			if (c->dfs_state == NL80211_DFS_USABLE)
416 				count++;
417 		}
418 	}
419 
420 	return count;
421 }
422 
423 bool cfg80211_chandef_dfs_usable(struct wiphy *wiphy,
424 				 const struct cfg80211_chan_def *chandef)
425 {
426 	int width;
427 	int r1, r2 = 0;
428 
429 	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
430 		return false;
431 
432 	width = cfg80211_chandef_get_width(chandef);
433 	if (width < 0)
434 		return false;
435 
436 	r1 = cfg80211_get_chans_dfs_usable(wiphy, chandef->center_freq1,
437 					  width);
438 
439 	if (r1 < 0)
440 		return false;
441 
442 	switch (chandef->width) {
443 	case NL80211_CHAN_WIDTH_80P80:
444 		WARN_ON(!chandef->center_freq2);
445 		r2 = cfg80211_get_chans_dfs_usable(wiphy,
446 						   chandef->center_freq2,
447 						   width);
448 		if (r2 < 0)
449 			return false;
450 		break;
451 	default:
452 		WARN_ON(chandef->center_freq2);
453 		break;
454 	}
455 
456 	return (r1 + r2 > 0);
457 }
458 
459 
460 static bool cfg80211_get_chans_dfs_available(struct wiphy *wiphy,
461 					     u32 center_freq,
462 					     u32 bandwidth)
463 {
464 	struct ieee80211_channel *c;
465 	u32 freq, start_freq, end_freq;
466 
467 	start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
468 	end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
469 
470 	/*
471 	 * Check entire range of channels for the bandwidth.
472 	 * If any channel in between is disabled or has not
473 	 * had gone through CAC return false
474 	 */
475 	for (freq = start_freq; freq <= end_freq; freq += 20) {
476 		c = ieee80211_get_channel(wiphy, freq);
477 		if (!c)
478 			return false;
479 
480 		if (c->flags & IEEE80211_CHAN_DISABLED)
481 			return false;
482 
483 		if ((c->flags & IEEE80211_CHAN_RADAR)  &&
484 		    (c->dfs_state != NL80211_DFS_AVAILABLE))
485 			return false;
486 	}
487 
488 	return true;
489 }
490 
491 static bool cfg80211_chandef_dfs_available(struct wiphy *wiphy,
492 				const struct cfg80211_chan_def *chandef)
493 {
494 	int width;
495 	int r;
496 
497 	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
498 		return false;
499 
500 	width = cfg80211_chandef_get_width(chandef);
501 	if (width < 0)
502 		return false;
503 
504 	r = cfg80211_get_chans_dfs_available(wiphy, chandef->center_freq1,
505 					     width);
506 
507 	/* If any of channels unavailable for cf1 just return */
508 	if (!r)
509 		return r;
510 
511 	switch (chandef->width) {
512 	case NL80211_CHAN_WIDTH_80P80:
513 		WARN_ON(!chandef->center_freq2);
514 		r = cfg80211_get_chans_dfs_available(wiphy,
515 						     chandef->center_freq2,
516 						     width);
517 		break;
518 	default:
519 		WARN_ON(chandef->center_freq2);
520 		break;
521 	}
522 
523 	return r;
524 }
525 
526 static unsigned int cfg80211_get_chans_dfs_cac_time(struct wiphy *wiphy,
527 						    u32 center_freq,
528 						    u32 bandwidth)
529 {
530 	struct ieee80211_channel *c;
531 	u32 start_freq, end_freq, freq;
532 	unsigned int dfs_cac_ms = 0;
533 
534 	start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
535 	end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
536 
537 	for (freq = start_freq; freq <= end_freq; freq += 20) {
538 		c = ieee80211_get_channel(wiphy, freq);
539 		if (!c)
540 			return 0;
541 
542 		if (c->flags & IEEE80211_CHAN_DISABLED)
543 			return 0;
544 
545 		if (!(c->flags & IEEE80211_CHAN_RADAR))
546 			continue;
547 
548 		if (c->dfs_cac_ms > dfs_cac_ms)
549 			dfs_cac_ms = c->dfs_cac_ms;
550 	}
551 
552 	return dfs_cac_ms;
553 }
554 
555 unsigned int
556 cfg80211_chandef_dfs_cac_time(struct wiphy *wiphy,
557 			      const struct cfg80211_chan_def *chandef)
558 {
559 	int width;
560 	unsigned int t1 = 0, t2 = 0;
561 
562 	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
563 		return 0;
564 
565 	width = cfg80211_chandef_get_width(chandef);
566 	if (width < 0)
567 		return 0;
568 
569 	t1 = cfg80211_get_chans_dfs_cac_time(wiphy,
570 					     chandef->center_freq1,
571 					     width);
572 
573 	if (!chandef->center_freq2)
574 		return t1;
575 
576 	t2 = cfg80211_get_chans_dfs_cac_time(wiphy,
577 					     chandef->center_freq2,
578 					     width);
579 
580 	return max(t1, t2);
581 }
582 
583 static bool cfg80211_secondary_chans_ok(struct wiphy *wiphy,
584 					u32 center_freq, u32 bandwidth,
585 					u32 prohibited_flags)
586 {
587 	struct ieee80211_channel *c;
588 	u32 freq, start_freq, end_freq;
589 
590 	start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
591 	end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
592 
593 	for (freq = start_freq; freq <= end_freq; freq += 20) {
594 		c = ieee80211_get_channel(wiphy, freq);
595 		if (!c || c->flags & prohibited_flags)
596 			return false;
597 	}
598 
599 	return true;
600 }
601 
602 bool cfg80211_chandef_usable(struct wiphy *wiphy,
603 			     const struct cfg80211_chan_def *chandef,
604 			     u32 prohibited_flags)
605 {
606 	struct ieee80211_sta_ht_cap *ht_cap;
607 	struct ieee80211_sta_vht_cap *vht_cap;
608 	u32 width, control_freq, cap;
609 
610 	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
611 		return false;
612 
613 	ht_cap = &wiphy->bands[chandef->chan->band]->ht_cap;
614 	vht_cap = &wiphy->bands[chandef->chan->band]->vht_cap;
615 
616 	control_freq = chandef->chan->center_freq;
617 
618 	switch (chandef->width) {
619 	case NL80211_CHAN_WIDTH_5:
620 		width = 5;
621 		break;
622 	case NL80211_CHAN_WIDTH_10:
623 		prohibited_flags |= IEEE80211_CHAN_NO_10MHZ;
624 		width = 10;
625 		break;
626 	case NL80211_CHAN_WIDTH_20:
627 		if (!ht_cap->ht_supported)
628 			return false;
629 	case NL80211_CHAN_WIDTH_20_NOHT:
630 		prohibited_flags |= IEEE80211_CHAN_NO_20MHZ;
631 		width = 20;
632 		break;
633 	case NL80211_CHAN_WIDTH_40:
634 		width = 40;
635 		if (!ht_cap->ht_supported)
636 			return false;
637 		if (!(ht_cap->cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) ||
638 		    ht_cap->cap & IEEE80211_HT_CAP_40MHZ_INTOLERANT)
639 			return false;
640 		if (chandef->center_freq1 < control_freq &&
641 		    chandef->chan->flags & IEEE80211_CHAN_NO_HT40MINUS)
642 			return false;
643 		if (chandef->center_freq1 > control_freq &&
644 		    chandef->chan->flags & IEEE80211_CHAN_NO_HT40PLUS)
645 			return false;
646 		break;
647 	case NL80211_CHAN_WIDTH_80P80:
648 		cap = vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
649 		if (cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
650 			return false;
651 	case NL80211_CHAN_WIDTH_80:
652 		if (!vht_cap->vht_supported)
653 			return false;
654 		prohibited_flags |= IEEE80211_CHAN_NO_80MHZ;
655 		width = 80;
656 		break;
657 	case NL80211_CHAN_WIDTH_160:
658 		if (!vht_cap->vht_supported)
659 			return false;
660 		cap = vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
661 		if (cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ &&
662 		    cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
663 			return false;
664 		prohibited_flags |= IEEE80211_CHAN_NO_160MHZ;
665 		width = 160;
666 		break;
667 	default:
668 		WARN_ON_ONCE(1);
669 		return false;
670 	}
671 
672 	/*
673 	 * TODO: What if there are only certain 80/160/80+80 MHz channels
674 	 *	 allowed by the driver, or only certain combinations?
675 	 *	 For 40 MHz the driver can set the NO_HT40 flags, but for
676 	 *	 80/160 MHz and in particular 80+80 MHz this isn't really
677 	 *	 feasible and we only have NO_80MHZ/NO_160MHZ so far but
678 	 *	 no way to cover 80+80 MHz or more complex restrictions.
679 	 *	 Note that such restrictions also need to be advertised to
680 	 *	 userspace, for example for P2P channel selection.
681 	 */
682 
683 	if (width > 20)
684 		prohibited_flags |= IEEE80211_CHAN_NO_OFDM;
685 
686 	/* 5 and 10 MHz are only defined for the OFDM PHY */
687 	if (width < 20)
688 		prohibited_flags |= IEEE80211_CHAN_NO_OFDM;
689 
690 
691 	if (!cfg80211_secondary_chans_ok(wiphy, chandef->center_freq1,
692 					 width, prohibited_flags))
693 		return false;
694 
695 	if (!chandef->center_freq2)
696 		return true;
697 	return cfg80211_secondary_chans_ok(wiphy, chandef->center_freq2,
698 					   width, prohibited_flags);
699 }
700 EXPORT_SYMBOL(cfg80211_chandef_usable);
701 
702 /*
703  * Check if the channel can be used under permissive conditions mandated by
704  * some regulatory bodies, i.e., the channel is marked with
705  * IEEE80211_CHAN_IR_CONCURRENT and there is an additional station interface
706  * associated to an AP on the same channel or on the same UNII band
707  * (assuming that the AP is an authorized master).
708  * In addition allow operation on a channel on which indoor operation is
709  * allowed, iff we are currently operating in an indoor environment.
710  */
711 static bool cfg80211_ir_permissive_chan(struct wiphy *wiphy,
712 					enum nl80211_iftype iftype,
713 					struct ieee80211_channel *chan)
714 {
715 	struct wireless_dev *wdev;
716 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
717 
718 	ASSERT_RTNL();
719 
720 	if (!IS_ENABLED(CONFIG_CFG80211_REG_RELAX_NO_IR) ||
721 	    !(wiphy->regulatory_flags & REGULATORY_ENABLE_RELAX_NO_IR))
722 		return false;
723 
724 	/* only valid for GO and TDLS off-channel (station/p2p-CL) */
725 	if (iftype != NL80211_IFTYPE_P2P_GO &&
726 	    iftype != NL80211_IFTYPE_STATION &&
727 	    iftype != NL80211_IFTYPE_P2P_CLIENT)
728 		return false;
729 
730 	if (regulatory_indoor_allowed() &&
731 	    (chan->flags & IEEE80211_CHAN_INDOOR_ONLY))
732 		return true;
733 
734 	if (!(chan->flags & IEEE80211_CHAN_IR_CONCURRENT))
735 		return false;
736 
737 	/*
738 	 * Generally, it is possible to rely on another device/driver to allow
739 	 * the IR concurrent relaxation, however, since the device can further
740 	 * enforce the relaxation (by doing a similar verifications as this),
741 	 * and thus fail the GO instantiation, consider only the interfaces of
742 	 * the current registered device.
743 	 */
744 	list_for_each_entry(wdev, &rdev->wiphy.wdev_list, list) {
745 		struct ieee80211_channel *other_chan = NULL;
746 		int r1, r2;
747 
748 		wdev_lock(wdev);
749 		if (wdev->iftype == NL80211_IFTYPE_STATION &&
750 		    wdev->current_bss)
751 			other_chan = wdev->current_bss->pub.channel;
752 
753 		/*
754 		 * If a GO already operates on the same GO_CONCURRENT channel,
755 		 * this one (maybe the same one) can beacon as well. We allow
756 		 * the operation even if the station we relied on with
757 		 * GO_CONCURRENT is disconnected now. But then we must make sure
758 		 * we're not outdoor on an indoor-only channel.
759 		 */
760 		if (iftype == NL80211_IFTYPE_P2P_GO &&
761 		    wdev->iftype == NL80211_IFTYPE_P2P_GO &&
762 		    wdev->beacon_interval &&
763 		    !(chan->flags & IEEE80211_CHAN_INDOOR_ONLY))
764 			other_chan = wdev->chandef.chan;
765 		wdev_unlock(wdev);
766 
767 		if (!other_chan)
768 			continue;
769 
770 		if (chan == other_chan)
771 			return true;
772 
773 		if (chan->band != NL80211_BAND_5GHZ)
774 			continue;
775 
776 		r1 = cfg80211_get_unii(chan->center_freq);
777 		r2 = cfg80211_get_unii(other_chan->center_freq);
778 
779 		if (r1 != -EINVAL && r1 == r2) {
780 			/*
781 			 * At some locations channels 149-165 are considered a
782 			 * bundle, but at other locations, e.g., Indonesia,
783 			 * channels 149-161 are considered a bundle while
784 			 * channel 165 is left out and considered to be in a
785 			 * different bundle. Thus, in case that there is a
786 			 * station interface connected to an AP on channel 165,
787 			 * it is assumed that channels 149-161 are allowed for
788 			 * GO operations. However, having a station interface
789 			 * connected to an AP on channels 149-161, does not
790 			 * allow GO operation on channel 165.
791 			 */
792 			if (chan->center_freq == 5825 &&
793 			    other_chan->center_freq != 5825)
794 				continue;
795 			return true;
796 		}
797 	}
798 
799 	return false;
800 }
801 
802 static bool _cfg80211_reg_can_beacon(struct wiphy *wiphy,
803 				     struct cfg80211_chan_def *chandef,
804 				     enum nl80211_iftype iftype,
805 				     bool check_no_ir)
806 {
807 	bool res;
808 	u32 prohibited_flags = IEEE80211_CHAN_DISABLED |
809 			       IEEE80211_CHAN_RADAR;
810 
811 	trace_cfg80211_reg_can_beacon(wiphy, chandef, iftype, check_no_ir);
812 
813 	if (check_no_ir)
814 		prohibited_flags |= IEEE80211_CHAN_NO_IR;
815 
816 	if (cfg80211_chandef_dfs_required(wiphy, chandef, iftype) > 0 &&
817 	    cfg80211_chandef_dfs_available(wiphy, chandef)) {
818 		/* We can skip IEEE80211_CHAN_NO_IR if chandef dfs available */
819 		prohibited_flags = IEEE80211_CHAN_DISABLED;
820 	}
821 
822 	res = cfg80211_chandef_usable(wiphy, chandef, prohibited_flags);
823 
824 	trace_cfg80211_return_bool(res);
825 	return res;
826 }
827 
828 bool cfg80211_reg_can_beacon(struct wiphy *wiphy,
829 			     struct cfg80211_chan_def *chandef,
830 			     enum nl80211_iftype iftype)
831 {
832 	return _cfg80211_reg_can_beacon(wiphy, chandef, iftype, true);
833 }
834 EXPORT_SYMBOL(cfg80211_reg_can_beacon);
835 
836 bool cfg80211_reg_can_beacon_relax(struct wiphy *wiphy,
837 				   struct cfg80211_chan_def *chandef,
838 				   enum nl80211_iftype iftype)
839 {
840 	bool check_no_ir;
841 
842 	ASSERT_RTNL();
843 
844 	/*
845 	 * Under certain conditions suggested by some regulatory bodies a
846 	 * GO/STA can IR on channels marked with IEEE80211_NO_IR. Set this flag
847 	 * only if such relaxations are not enabled and the conditions are not
848 	 * met.
849 	 */
850 	check_no_ir = !cfg80211_ir_permissive_chan(wiphy, iftype,
851 						   chandef->chan);
852 
853 	return _cfg80211_reg_can_beacon(wiphy, chandef, iftype, check_no_ir);
854 }
855 EXPORT_SYMBOL(cfg80211_reg_can_beacon_relax);
856 
857 int cfg80211_set_monitor_channel(struct cfg80211_registered_device *rdev,
858 				 struct cfg80211_chan_def *chandef)
859 {
860 	if (!rdev->ops->set_monitor_channel)
861 		return -EOPNOTSUPP;
862 	if (!cfg80211_has_monitors_only(rdev))
863 		return -EBUSY;
864 
865 	return rdev_set_monitor_channel(rdev, chandef);
866 }
867 
868 void
869 cfg80211_get_chan_state(struct wireless_dev *wdev,
870 		        struct ieee80211_channel **chan,
871 		        enum cfg80211_chan_mode *chanmode,
872 		        u8 *radar_detect)
873 {
874 	int ret;
875 
876 	*chan = NULL;
877 	*chanmode = CHAN_MODE_UNDEFINED;
878 
879 	ASSERT_WDEV_LOCK(wdev);
880 
881 	if (wdev->netdev && !netif_running(wdev->netdev))
882 		return;
883 
884 	switch (wdev->iftype) {
885 	case NL80211_IFTYPE_ADHOC:
886 		if (wdev->current_bss) {
887 			*chan = wdev->current_bss->pub.channel;
888 			*chanmode = (wdev->ibss_fixed &&
889 				     !wdev->ibss_dfs_possible)
890 				  ? CHAN_MODE_SHARED
891 				  : CHAN_MODE_EXCLUSIVE;
892 
893 			/* consider worst-case - IBSS can try to return to the
894 			 * original user-specified channel as creator */
895 			if (wdev->ibss_dfs_possible)
896 				*radar_detect |= BIT(wdev->chandef.width);
897 			return;
898 		}
899 		break;
900 	case NL80211_IFTYPE_STATION:
901 	case NL80211_IFTYPE_P2P_CLIENT:
902 		if (wdev->current_bss) {
903 			*chan = wdev->current_bss->pub.channel;
904 			*chanmode = CHAN_MODE_SHARED;
905 			return;
906 		}
907 		break;
908 	case NL80211_IFTYPE_AP:
909 	case NL80211_IFTYPE_P2P_GO:
910 		if (wdev->cac_started) {
911 			*chan = wdev->chandef.chan;
912 			*chanmode = CHAN_MODE_SHARED;
913 			*radar_detect |= BIT(wdev->chandef.width);
914 		} else if (wdev->beacon_interval) {
915 			*chan = wdev->chandef.chan;
916 			*chanmode = CHAN_MODE_SHARED;
917 
918 			ret = cfg80211_chandef_dfs_required(wdev->wiphy,
919 							    &wdev->chandef,
920 							    wdev->iftype);
921 			WARN_ON(ret < 0);
922 			if (ret > 0)
923 				*radar_detect |= BIT(wdev->chandef.width);
924 		}
925 		return;
926 	case NL80211_IFTYPE_MESH_POINT:
927 		if (wdev->mesh_id_len) {
928 			*chan = wdev->chandef.chan;
929 			*chanmode = CHAN_MODE_SHARED;
930 
931 			ret = cfg80211_chandef_dfs_required(wdev->wiphy,
932 							    &wdev->chandef,
933 							    wdev->iftype);
934 			WARN_ON(ret < 0);
935 			if (ret > 0)
936 				*radar_detect |= BIT(wdev->chandef.width);
937 		}
938 		return;
939 	case NL80211_IFTYPE_OCB:
940 		if (wdev->chandef.chan) {
941 			*chan = wdev->chandef.chan;
942 			*chanmode = CHAN_MODE_SHARED;
943 			return;
944 		}
945 		break;
946 	case NL80211_IFTYPE_MONITOR:
947 	case NL80211_IFTYPE_AP_VLAN:
948 	case NL80211_IFTYPE_WDS:
949 	case NL80211_IFTYPE_P2P_DEVICE:
950 	case NL80211_IFTYPE_NAN:
951 		/* these interface types don't really have a channel */
952 		return;
953 	case NL80211_IFTYPE_UNSPECIFIED:
954 	case NUM_NL80211_IFTYPES:
955 		WARN_ON(1);
956 	}
957 }
958