[deliverable/linux.git] / net / wireless / chan.c

/*
 * This file contains helper code to handle channel
 * settings and keeping track of what is possible at
 * any point in time.
 *
 * Copyright 2009	Johannes Berg <johannes@sipsolutions.net>
 */

#include <linux/export.h>
#include <net/cfg80211.h>
#include "core.h"
#include "rdev-ops.h"

void cfg80211_chandef_create(struct cfg80211_chan_def *chandef,
			     struct ieee80211_channel *chan,
			     enum nl80211_channel_type chan_type)
{
	if (WARN_ON(!chan))
		return;

	chandef->chan = chan;
	chandef->center_freq2 = 0;

	switch (chan_type) {
	case NL80211_CHAN_NO_HT:
		chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
		chandef->center_freq1 = chan->center_freq;
		break;
	case NL80211_CHAN_HT20:
		chandef->width = NL80211_CHAN_WIDTH_20;
		chandef->center_freq1 = chan->center_freq;
		break;
	case NL80211_CHAN_HT40PLUS:
		chandef->width = NL80211_CHAN_WIDTH_40;
		chandef->center_freq1 = chan->center_freq + 10;
		break;
	case NL80211_CHAN_HT40MINUS:
		chandef->width = NL80211_CHAN_WIDTH_40;
		chandef->center_freq1 = chan->center_freq - 10;
		break;
	default:
		WARN_ON(1);
	}
}
EXPORT_SYMBOL(cfg80211_chandef_create);

bool cfg80211_chandef_valid(const struct cfg80211_chan_def *chandef)
{
	u32 control_freq;

	if (!chandef->chan)
		return false;

	control_freq = chandef->chan->center_freq;

	switch (chandef->width) {
	case NL80211_CHAN_WIDTH_5:
	case NL80211_CHAN_WIDTH_10:
	case NL80211_CHAN_WIDTH_20:
	case NL80211_CHAN_WIDTH_20_NOHT:
		if (chandef->center_freq1 != control_freq)
			return false;
		if (chandef->center_freq2)
			return false;
		break;
	case NL80211_CHAN_WIDTH_40:
		if (chandef->center_freq1 != control_freq + 10 &&
		    chandef->center_freq1 != control_freq - 10)
			return false;
		if (chandef->center_freq2)
			return false;
		break;
	case NL80211_CHAN_WIDTH_80P80:
		if (chandef->center_freq1 != control_freq + 30 &&
		    chandef->center_freq1 != control_freq + 10 &&
		    chandef->center_freq1 != control_freq - 10 &&
		    chandef->center_freq1 != control_freq - 30)
			return false;
		if (!chandef->center_freq2)
			return false;
		/* adjacent is not allowed -- that's a 160 MHz channel */
		if (chandef->center_freq1 - chandef->center_freq2 == 80 ||
		    chandef->center_freq2 - chandef->center_freq1 == 80)
			return false;
		break;
	case NL80211_CHAN_WIDTH_80:
		if (chandef->center_freq1 != control_freq + 30 &&
		    chandef->center_freq1 != control_freq + 10 &&
		    chandef->center_freq1 != control_freq - 10 &&
		    chandef->center_freq1 != control_freq - 30)
			return false;
		if (chandef->center_freq2)
			return false;
		break;
	case NL80211_CHAN_WIDTH_160:
		if (chandef->center_freq1 != control_freq + 70 &&
		    chandef->center_freq1 != control_freq + 50 &&
		    chandef->center_freq1 != control_freq + 30 &&
		    chandef->center_freq1 != control_freq + 10 &&
		    chandef->center_freq1 != control_freq - 10 &&
		    chandef->center_freq1 != control_freq - 30 &&
		    chandef->center_freq1 != control_freq - 50 &&
		    chandef->center_freq1 != control_freq - 70)
			return false;
		if (chandef->center_freq2)
			return false;
		break;
	default:
		return false;
	}

	return true;
}
EXPORT_SYMBOL(cfg80211_chandef_valid);

static void chandef_primary_freqs(const struct cfg80211_chan_def *c,
				  int *pri40, int *pri80)
{
	int tmp;

	switch (c->width) {
	case NL80211_CHAN_WIDTH_40:
		*pri40 = c->center_freq1;
		*pri80 = 0;
		break;
	case NL80211_CHAN_WIDTH_80:
	case NL80211_CHAN_WIDTH_80P80:
		*pri80 = c->center_freq1;
		/* n_P20 */
		tmp = (30 + c->chan->center_freq - c->center_freq1)/20;
		/* n_P40 */
		tmp /= 2;
		/* freq_P40 */
		*pri40 = c->center_freq1 - 20 + 40 * tmp;
		break;
	case NL80211_CHAN_WIDTH_160:
		/* n_P20 */
		tmp = (70 + c->chan->center_freq - c->center_freq1)/20;
		/* n_P40 */
		tmp /= 2;
		/* freq_P40 */
		*pri40 = c->center_freq1 - 60 + 40 * tmp;
		/* n_P80 */
		tmp /= 2;
		*pri80 = c->center_freq1 - 40 + 80 * tmp;
		break;
	default:
		WARN_ON_ONCE(1);
	}
}

static int cfg80211_chandef_get_width(const struct cfg80211_chan_def *c)
{
	int width;

	switch (c->width) {
	case NL80211_CHAN_WIDTH_5:
		width = 5;
		break;
	case NL80211_CHAN_WIDTH_10:
		width = 10;
		break;
	case NL80211_CHAN_WIDTH_20:
	case NL80211_CHAN_WIDTH_20_NOHT:
		width = 20;
		break;
	case NL80211_CHAN_WIDTH_40:
		width = 40;
		break;
	case NL80211_CHAN_WIDTH_80P80:
	case NL80211_CHAN_WIDTH_80:
		width = 80;
		break;
	case NL80211_CHAN_WIDTH_160:
		width = 160;
		break;
	default:
		WARN_ON_ONCE(1);
		return -1;
	}
	return width;
}

const struct cfg80211_chan_def *
cfg80211_chandef_compatible(const struct cfg80211_chan_def *c1,
			    const struct cfg80211_chan_def *c2)
{
	u32 c1_pri40, c1_pri80, c2_pri40, c2_pri80;

	/* If they are identical, return */
	if (cfg80211_chandef_identical(c1, c2))
		return c1;

	/* otherwise, must have same control channel */
	if (c1->chan != c2->chan)
		return NULL;

	/*
	 * If they have the same width, but aren't identical,
	 * then they can't be compatible.
	 */
	if (c1->width == c2->width)
		return NULL;

	/*
	 * can't be compatible if one of them is 5 or 10 MHz,
	 * but they don't have the same width.
	 */
	if (c1->width == NL80211_CHAN_WIDTH_5 ||
	    c1->width == NL80211_CHAN_WIDTH_10 ||
	    c2->width == NL80211_CHAN_WIDTH_5 ||
	    c2->width == NL80211_CHAN_WIDTH_10)
		return NULL;

	if (c1->width == NL80211_CHAN_WIDTH_20_NOHT ||
	    c1->width == NL80211_CHAN_WIDTH_20)
		return c2;

	if (c2->width == NL80211_CHAN_WIDTH_20_NOHT ||
	    c2->width == NL80211_CHAN_WIDTH_20)
		return c1;

	chandef_primary_freqs(c1, &c1_pri40, &c1_pri80);
	chandef_primary_freqs(c2, &c2_pri40, &c2_pri80);

	if (c1_pri40 != c2_pri40)
		return NULL;

	WARN_ON(!c1_pri80 && !c2_pri80);
	if (c1_pri80 && c2_pri80 && c1_pri80 != c2_pri80)
		return NULL;

	if (c1->width > c2->width)
		return c1;
	return c2;
}
EXPORT_SYMBOL(cfg80211_chandef_compatible);

static void cfg80211_set_chans_dfs_state(struct wiphy *wiphy, u32 center_freq,
					 u32 bandwidth,
					 enum nl80211_dfs_state dfs_state)
{
	struct ieee80211_channel *c;
	u32 freq;

	for (freq = center_freq - bandwidth/2 + 10;
	     freq <= center_freq + bandwidth/2 - 10;
	     freq += 20) {
		c = ieee80211_get_channel(wiphy, freq);
		if (!c || !(c->flags & IEEE80211_CHAN_RADAR))
			continue;

		c->dfs_state = dfs_state;
		c->dfs_state_entered = jiffies;
	}
}

void cfg80211_set_dfs_state(struct wiphy *wiphy,
			    const struct cfg80211_chan_def *chandef,
			    enum nl80211_dfs_state dfs_state)
{
	int width;

	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
		return;

	width = cfg80211_chandef_get_width(chandef);
	if (width < 0)
		return;

	cfg80211_set_chans_dfs_state(wiphy, chandef->center_freq1,
				     width, dfs_state);

	if (!chandef->center_freq2)
		return;
	cfg80211_set_chans_dfs_state(wiphy, chandef->center_freq2,
				     width, dfs_state);
}

static u32 cfg80211_get_start_freq(u32 center_freq,
				   u32 bandwidth)
{
	u32 start_freq;

	if (bandwidth <= 20)
		start_freq = center_freq;
	else
		start_freq = center_freq - bandwidth/2 + 10;

	return start_freq;
}

static u32 cfg80211_get_end_freq(u32 center_freq,
				 u32 bandwidth)
{
	u32 end_freq;

	if (bandwidth <= 20)
		end_freq = center_freq;
	else
		end_freq = center_freq + bandwidth/2 - 10;

	return end_freq;
}

static int cfg80211_get_chans_dfs_required(struct wiphy *wiphy,
					    u32 center_freq,
					    u32 bandwidth)
{
	struct ieee80211_channel *c;
	u32 freq, start_freq, end_freq;

	start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
	end_freq = cfg80211_get_end_freq(center_freq, bandwidth);

	for (freq = start_freq; freq <= end_freq; freq += 20) {
		c = ieee80211_get_channel(wiphy, freq);
		if (!c)
			return -EINVAL;

		if (c->flags & IEEE80211_CHAN_RADAR)
			return 1;
	}
	return 0;
}


int cfg80211_chandef_dfs_required(struct wiphy *wiphy,
				  const struct cfg80211_chan_def *chandef)
{
	int width;
	int r;

	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
		return -EINVAL;

	width = cfg80211_chandef_get_width(chandef);
	if (width < 0)
		return -EINVAL;

	r = cfg80211_get_chans_dfs_required(wiphy, chandef->center_freq1,
					    width);
	if (r)
		return r;

	if (!chandef->center_freq2)
		return 0;

	return cfg80211_get_chans_dfs_required(wiphy, chandef->center_freq2,
					       width);
}
EXPORT_SYMBOL(cfg80211_chandef_dfs_required);

static bool cfg80211_secondary_chans_ok(struct wiphy *wiphy,
					u32 center_freq, u32 bandwidth,
					u32 prohibited_flags)
{
	struct ieee80211_channel *c;
	u32 freq, start_freq, end_freq;

	start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
	end_freq = cfg80211_get_end_freq(center_freq, bandwidth);

	for (freq = start_freq; freq <= end_freq; freq += 20) {
		c = ieee80211_get_channel(wiphy, freq);
		if (!c)
			return false;

		/* check for radar flags */
		if ((prohibited_flags & c->flags & IEEE80211_CHAN_RADAR) &&
		    (c->dfs_state != NL80211_DFS_AVAILABLE))
			return false;

		/* check for the other flags */
		if (c->flags & prohibited_flags & ~IEEE80211_CHAN_RADAR)
			return false;
	}

	return true;
}

bool cfg80211_chandef_usable(struct wiphy *wiphy,
			     const struct cfg80211_chan_def *chandef,
			     u32 prohibited_flags)
{
	struct ieee80211_sta_ht_cap *ht_cap;
	struct ieee80211_sta_vht_cap *vht_cap;
	u32 width, control_freq;

	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
		return false;

	ht_cap = &wiphy->bands[chandef->chan->band]->ht_cap;
	vht_cap = &wiphy->bands[chandef->chan->band]->vht_cap;

	control_freq = chandef->chan->center_freq;

	switch (chandef->width) {
	case NL80211_CHAN_WIDTH_5:
		width = 5;
		break;
	case NL80211_CHAN_WIDTH_10:
		width = 10;
		break;
	case NL80211_CHAN_WIDTH_20:
		if (!ht_cap->ht_supported)
			return false;
	case NL80211_CHAN_WIDTH_20_NOHT:
		width = 20;
		break;
	case NL80211_CHAN_WIDTH_40:
		width = 40;
		if (!ht_cap->ht_supported)
			return false;
		if (!(ht_cap->cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) ||
		    ht_cap->cap & IEEE80211_HT_CAP_40MHZ_INTOLERANT)
			return false;
		if (chandef->center_freq1 < control_freq &&
		    chandef->chan->flags & IEEE80211_CHAN_NO_HT40MINUS)
			return false;
		if (chandef->center_freq1 > control_freq &&
		    chandef->chan->flags & IEEE80211_CHAN_NO_HT40PLUS)
			return false;
		break;
	case NL80211_CHAN_WIDTH_80P80:
		if (!(vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ))
			return false;
	case NL80211_CHAN_WIDTH_80:
		if (!vht_cap->vht_supported)
			return false;
		prohibited_flags |= IEEE80211_CHAN_NO_80MHZ;
		width = 80;
		break;
	case NL80211_CHAN_WIDTH_160:
		if (!vht_cap->vht_supported)
			return false;
		if (!(vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ))
			return false;
		prohibited_flags |= IEEE80211_CHAN_NO_160MHZ;
		width = 160;
		break;
	default:
		WARN_ON_ONCE(1);
		return false;
	}

	/*
	 * TODO: What if there are only certain 80/160/80+80 MHz channels
	 *	 allowed by the driver, or only certain combinations?
	 *	 For 40 MHz the driver can set the NO_HT40 flags, but for
	 *	 80/160 MHz and in particular 80+80 MHz this isn't really
	 *	 feasible and we only have NO_80MHZ/NO_160MHZ so far but
	 *	 no way to cover 80+80 MHz or more complex restrictions.
	 *	 Note that such restrictions also need to be advertised to
	 *	 userspace, for example for P2P channel selection.
	 */

	if (width > 20)
		prohibited_flags |= IEEE80211_CHAN_NO_OFDM;

	/* 5 and 10 MHz are only defined for the OFDM PHY */
	if (width < 20)
		prohibited_flags |= IEEE80211_CHAN_NO_OFDM;


	if (!cfg80211_secondary_chans_ok(wiphy, chandef->center_freq1,
					 width, prohibited_flags))
		return false;

	if (!chandef->center_freq2)
		return true;
	return cfg80211_secondary_chans_ok(wiphy, chandef->center_freq2,
					   width, prohibited_flags);
}
EXPORT_SYMBOL(cfg80211_chandef_usable);

bool cfg80211_reg_can_beacon(struct wiphy *wiphy,
			     struct cfg80211_chan_def *chandef)
{
	bool res;

	trace_cfg80211_reg_can_beacon(wiphy, chandef);

	res = cfg80211_chandef_usable(wiphy, chandef,
				      IEEE80211_CHAN_DISABLED |
				      IEEE80211_CHAN_NO_IR |
				      IEEE80211_CHAN_RADAR);

	trace_cfg80211_return_bool(res);
	return res;
}
EXPORT_SYMBOL(cfg80211_reg_can_beacon);

int cfg80211_set_monitor_channel(struct cfg80211_registered_device *rdev,
				 struct cfg80211_chan_def *chandef)
{
	if (!rdev->ops->set_monitor_channel)
		return -EOPNOTSUPP;
	if (!cfg80211_has_monitors_only(rdev))
		return -EBUSY;

	return rdev_set_monitor_channel(rdev, chandef);
}

void
cfg80211_get_chan_state(struct wireless_dev *wdev,
		        struct ieee80211_channel **chan,
		        enum cfg80211_chan_mode *chanmode)
{
	*chan = NULL;
	*chanmode = CHAN_MODE_UNDEFINED;

	ASSERT_WDEV_LOCK(wdev);

	if (wdev->netdev && !netif_running(wdev->netdev))
		return;

	switch (wdev->iftype) {
	case NL80211_IFTYPE_ADHOC:
		if (wdev->current_bss) {
			*chan = wdev->current_bss->pub.channel;
			*chanmode = (wdev->ibss_fixed &&
				     !wdev->ibss_dfs_possible)
				  ? CHAN_MODE_SHARED
				  : CHAN_MODE_EXCLUSIVE;
			return;
		}
	case NL80211_IFTYPE_STATION:
	case NL80211_IFTYPE_P2P_CLIENT:
		if (wdev->current_bss) {
			*chan = wdev->current_bss->pub.channel;
			*chanmode = CHAN_MODE_SHARED;
			return;
		}
		break;
	case NL80211_IFTYPE_AP:
	case NL80211_IFTYPE_P2P_GO:
		if (wdev->cac_started) {
			*chan = wdev->channel;
			*chanmode = CHAN_MODE_SHARED;
		} else if (wdev->beacon_interval) {
			*chan = wdev->channel;
			*chanmode = CHAN_MODE_SHARED;
		}
		return;
	case NL80211_IFTYPE_MESH_POINT:
		if (wdev->mesh_id_len) {
			*chan = wdev->channel;
			*chanmode = CHAN_MODE_SHARED;
		}
		return;
	case NL80211_IFTYPE_MONITOR:
	case NL80211_IFTYPE_AP_VLAN:
	case NL80211_IFTYPE_WDS:
		/* these interface types don't really have a channel */
		return;
	case NL80211_IFTYPE_P2P_DEVICE:
		if (wdev->wiphy->features &
				NL80211_FEATURE_P2P_DEVICE_NEEDS_CHANNEL)
			*chanmode = CHAN_MODE_EXCLUSIVE;
		return;
	case NL80211_IFTYPE_UNSPECIFIED:
	case NUM_NL80211_IFTYPES:
		WARN_ON(1);
	}

	return;
}
Commit	Line	Data
59bbb6f7 JB	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	*/
	8
54858ee5	9	#include <linux/export.h>
59bbb6f7 JB	10	#include <net/cfg80211.h>
59bbb6f7 JB	11	#include "core.h"
e35e4d28	12	#include "rdev-ops.h"
59bbb6f7	13
3d9d1d66 JB	14	void cfg80211_chandef_create(struct cfg80211_chan_def *chandef,
	15	struct ieee80211_channel *chan,
	16	enum nl80211_channel_type chan_type)
9236d838	17	{
3d9d1d66 JB	18	if (WARN_ON(!chan))
3d9d1d66 JB	19	return;
9236d838	20
3d9d1d66 JB	21	chandef->chan = chan;
3d9d1d66 JB	22	chandef->center_freq2 = 0;
4ee3e063	23
3d9d1d66 JB	24	switch (chan_type) {
	25	case NL80211_CHAN_NO_HT:
	26	chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
	27	chandef->center_freq1 = chan->center_freq;
	28	break;
	29	case NL80211_CHAN_HT20:
	30	chandef->width = NL80211_CHAN_WIDTH_20;
	31	chandef->center_freq1 = chan->center_freq;
	32	break;
9236d838	33	case NL80211_CHAN_HT40PLUS:
3d9d1d66 JB	34	chandef->width = NL80211_CHAN_WIDTH_40;
3d9d1d66 JB	35	chandef->center_freq1 = chan->center_freq + 10;
09a02fdb	36	break;
9236d838	37	case NL80211_CHAN_HT40MINUS:
3d9d1d66 JB	38	chandef->width = NL80211_CHAN_WIDTH_40;
3d9d1d66 JB	39	chandef->center_freq1 = chan->center_freq - 10;
09a02fdb	40	break;
9236d838	41	default:
3d9d1d66 JB	42	WARN_ON(1);
	43	}
	44	}
	45	EXPORT_SYMBOL(cfg80211_chandef_create);
	46
9f5e8f6e	47	bool cfg80211_chandef_valid(const struct cfg80211_chan_def *chandef)
3d9d1d66 JB	48	{
	49	u32 control_freq;
	50
	51	if (!chandef->chan)
	52	return false;
	53
	54	control_freq = chandef->chan->center_freq;
	55
	56	switch (chandef->width) {
2f301ab2 SW	57	case NL80211_CHAN_WIDTH_5:
2f301ab2 SW	58	case NL80211_CHAN_WIDTH_10:
3d9d1d66 JB	59	case NL80211_CHAN_WIDTH_20:
	60	case NL80211_CHAN_WIDTH_20_NOHT:
	61	if (chandef->center_freq1 != control_freq)
	62	return false;
	63	if (chandef->center_freq2)
	64	return false;
	65	break;
	66	case NL80211_CHAN_WIDTH_40:
	67	if (chandef->center_freq1 != control_freq + 10 &&
	68	chandef->center_freq1 != control_freq - 10)
	69	return false;
	70	if (chandef->center_freq2)
	71	return false;
	72	break;
	73	case NL80211_CHAN_WIDTH_80P80:
	74	if (chandef->center_freq1 != control_freq + 30 &&
	75	chandef->center_freq1 != control_freq + 10 &&
	76	chandef->center_freq1 != control_freq - 10 &&
	77	chandef->center_freq1 != control_freq - 30)
	78	return false;
	79	if (!chandef->center_freq2)
	80	return false;
9cab3151 JB	81	/* adjacent is not allowed -- that's a 160 MHz channel */
	82	if (chandef->center_freq1 - chandef->center_freq2 == 80 \|\|
	83	chandef->center_freq2 - chandef->center_freq1 == 80)
	84	return false;
3d9d1d66 JB	85	break;
	86	case NL80211_CHAN_WIDTH_80:
	87	if (chandef->center_freq1 != control_freq + 30 &&
	88	chandef->center_freq1 != control_freq + 10 &&
	89	chandef->center_freq1 != control_freq - 10 &&
	90	chandef->center_freq1 != control_freq - 30)
	91	return false;
	92	if (chandef->center_freq2)
	93	return false;
	94	break;
	95	case NL80211_CHAN_WIDTH_160:
	96	if (chandef->center_freq1 != control_freq + 70 &&
	97	chandef->center_freq1 != control_freq + 50 &&
	98	chandef->center_freq1 != control_freq + 30 &&
	99	chandef->center_freq1 != control_freq + 10 &&
	100	chandef->center_freq1 != control_freq - 10 &&
	101	chandef->center_freq1 != control_freq - 30 &&
	102	chandef->center_freq1 != control_freq - 50 &&
	103	chandef->center_freq1 != control_freq - 70)
	104	return false;
	105	if (chandef->center_freq2)
	106	return false;
	107	break;
	108	default:
	109	return false;
	110	}
	111
	112	return true;
	113	}
9f5e8f6e	114	EXPORT_SYMBOL(cfg80211_chandef_valid);
3d9d1d66 JB	115
	116	static void chandef_primary_freqs(const struct cfg80211_chan_def *c,
	117	int pri40, int pri80)
	118	{
	119	int tmp;
	120
	121	switch (c->width) {
	122	case NL80211_CHAN_WIDTH_40:
	123	*pri40 = c->center_freq1;
	124	*pri80 = 0;
	125	break;
	126	case NL80211_CHAN_WIDTH_80:
	127	case NL80211_CHAN_WIDTH_80P80:
	128	*pri80 = c->center_freq1;
	129	/* n_P20 */
	130	tmp = (30 + c->chan->center_freq - c->center_freq1)/20;
	131	/* n_P40 */
	132	tmp /= 2;
	133	/* freq_P40 */
	134	pri40 = c->center_freq1 - 20 + 40 tmp;
	135	break;
	136	case NL80211_CHAN_WIDTH_160:
	137	/* n_P20 */
	138	tmp = (70 + c->chan->center_freq - c->center_freq1)/20;
	139	/* n_P40 */
	140	tmp /= 2;
	141	/* freq_P40 */
	142	pri40 = c->center_freq1 - 60 + 40 tmp;
	143	/* n_P80 */
	144	tmp /= 2;
	145	pri80 = c->center_freq1 - 40 + 80 tmp;
	146	break;
	147	default:
	148	WARN_ON_ONCE(1);
	149	}
	150	}
	151
04f39047 SW	152	static int cfg80211_chandef_get_width(const struct cfg80211_chan_def *c)
	153	{
	154	int width;
	155
	156	switch (c->width) {
2f301ab2 SW	157	case NL80211_CHAN_WIDTH_5:
	158	width = 5;
	159	break;
	160	case NL80211_CHAN_WIDTH_10:
	161	width = 10;
	162	break;
04f39047 SW	163	case NL80211_CHAN_WIDTH_20:
	164	case NL80211_CHAN_WIDTH_20_NOHT:
	165	width = 20;
	166	break;
	167	case NL80211_CHAN_WIDTH_40:
	168	width = 40;
	169	break;
	170	case NL80211_CHAN_WIDTH_80P80:
	171	case NL80211_CHAN_WIDTH_80:
	172	width = 80;
	173	break;
	174	case NL80211_CHAN_WIDTH_160:
	175	width = 160;
	176	break;
	177	default:
	178	WARN_ON_ONCE(1);
	179	return -1;
	180	}
	181	return width;
	182	}
	183
3d9d1d66 JB	184	const struct cfg80211_chan_def *
	185	cfg80211_chandef_compatible(const struct cfg80211_chan_def *c1,
	186	const struct cfg80211_chan_def *c2)
	187	{
	188	u32 c1_pri40, c1_pri80, c2_pri40, c2_pri80;
	189
	190	/* If they are identical, return */
	191	if (cfg80211_chandef_identical(c1, c2))
	192	return c1;
	193
	194	/* otherwise, must have same control channel */
	195	if (c1->chan != c2->chan)
	196	return NULL;
	197
	198	/*
	199	* If they have the same width, but aren't identical,
	200	* then they can't be compatible.
	201	*/
	202	if (c1->width == c2->width)
	203	return NULL;
	204
2f301ab2 SW	205	/*
	206	* can't be compatible if one of them is 5 or 10 MHz,
	207	* but they don't have the same width.
	208	*/
	209	if (c1->width == NL80211_CHAN_WIDTH_5 \|\|
	210	c1->width == NL80211_CHAN_WIDTH_10 \|\|
	211	c2->width == NL80211_CHAN_WIDTH_5 \|\|
	212	c2->width == NL80211_CHAN_WIDTH_10)
	213	return NULL;
	214
3d9d1d66 JB	215	if (c1->width == NL80211_CHAN_WIDTH_20_NOHT \|\|
	216	c1->width == NL80211_CHAN_WIDTH_20)
	217	return c2;
	218
	219	if (c2->width == NL80211_CHAN_WIDTH_20_NOHT \|\|
	220	c2->width == NL80211_CHAN_WIDTH_20)
	221	return c1;
	222
	223	chandef_primary_freqs(c1, &c1_pri40, &c1_pri80);
	224	chandef_primary_freqs(c2, &c2_pri40, &c2_pri80);
	225
	226	if (c1_pri40 != c2_pri40)
	227	return NULL;
	228
	229	WARN_ON(!c1_pri80 && !c2_pri80);
	230	if (c1_pri80 && c2_pri80 && c1_pri80 != c2_pri80)
	231	return NULL;
	232
	233	if (c1->width > c2->width)
	234	return c1;
	235	return c2;
	236	}
	237	EXPORT_SYMBOL(cfg80211_chandef_compatible);
	238
04f39047 SW	239	static void cfg80211_set_chans_dfs_state(struct wiphy *wiphy, u32 center_freq,
	240	u32 bandwidth,
	241	enum nl80211_dfs_state dfs_state)
	242	{
	243	struct ieee80211_channel *c;
	244	u32 freq;
	245
	246	for (freq = center_freq - bandwidth/2 + 10;
	247	freq <= center_freq + bandwidth/2 - 10;
	248	freq += 20) {
	249	c = ieee80211_get_channel(wiphy, freq);
	250	if (!c \|\| !(c->flags & IEEE80211_CHAN_RADAR))
	251	continue;
	252
	253	c->dfs_state = dfs_state;
	254	c->dfs_state_entered = jiffies;
	255	}
	256	}
	257
	258	void cfg80211_set_dfs_state(struct wiphy *wiphy,
	259	const struct cfg80211_chan_def *chandef,
	260	enum nl80211_dfs_state dfs_state)
	261	{
	262	int width;
	263
	264	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
	265	return;
	266
	267	width = cfg80211_chandef_get_width(chandef);
	268	if (width < 0)
	269	return;
	270
	271	cfg80211_set_chans_dfs_state(wiphy, chandef->center_freq1,
	272	width, dfs_state);
	273
	274	if (!chandef->center_freq2)
	275	return;
	276	cfg80211_set_chans_dfs_state(wiphy, chandef->center_freq2,
	277	width, dfs_state);
	278	}
	279
40d1ba63 JD	280	static u32 cfg80211_get_start_freq(u32 center_freq,
	281	u32 bandwidth)
	282	{
	283	u32 start_freq;
	284
	285	if (bandwidth <= 20)
	286	start_freq = center_freq;
	287	else
	288	start_freq = center_freq - bandwidth/2 + 10;
	289
	290	return start_freq;
	291	}
	292
	293	static u32 cfg80211_get_end_freq(u32 center_freq,
	294	u32 bandwidth)
	295	{
	296	u32 end_freq;
	297
	298	if (bandwidth <= 20)
	299	end_freq = center_freq;
	300	else
	301	end_freq = center_freq + bandwidth/2 - 10;
	302
	303	return end_freq;
	304	}
	305
04f39047 SW	306	static int cfg80211_get_chans_dfs_required(struct wiphy *wiphy,
	307	u32 center_freq,
	308	u32 bandwidth)
	309	{
	310	struct ieee80211_channel *c;
2f301ab2 SW	311	u32 freq, start_freq, end_freq;
2f301ab2 SW	312
40d1ba63 JD	313	start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
40d1ba63 JD	314	end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
04f39047	315
2f301ab2	316	for (freq = start_freq; freq <= end_freq; freq += 20) {
04f39047 SW	317	c = ieee80211_get_channel(wiphy, freq);
	318	if (!c)
	319	return -EINVAL;
	320
	321	if (c->flags & IEEE80211_CHAN_RADAR)
	322	return 1;
	323	}
	324	return 0;
	325	}
	326
	327
	328	int cfg80211_chandef_dfs_required(struct wiphy *wiphy,
	329	const struct cfg80211_chan_def *chandef)
	330	{
	331	int width;
	332	int r;
	333
	334	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
	335	return -EINVAL;
	336
	337	width = cfg80211_chandef_get_width(chandef);
	338	if (width < 0)
	339	return -EINVAL;
	340
	341	r = cfg80211_get_chans_dfs_required(wiphy, chandef->center_freq1,
	342	width);
	343	if (r)
	344	return r;
	345
	346	if (!chandef->center_freq2)
	347	return 0;
	348
	349	return cfg80211_get_chans_dfs_required(wiphy, chandef->center_freq2,
	350	width);
	351	}
774f0734	352	EXPORT_SYMBOL(cfg80211_chandef_dfs_required);
04f39047	353
9f5e8f6e JB	354	static bool cfg80211_secondary_chans_ok(struct wiphy *wiphy,
	355	u32 center_freq, u32 bandwidth,
	356	u32 prohibited_flags)
3d9d1d66 JB	357	{
3d9d1d66 JB	358	struct ieee80211_channel *c;
2f301ab2 SW	359	u32 freq, start_freq, end_freq;
2f301ab2 SW	360
40d1ba63 JD	361	start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
40d1ba63 JD	362	end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
3d9d1d66	363
2f301ab2	364	for (freq = start_freq; freq <= end_freq; freq += 20) {
3d9d1d66	365	c = ieee80211_get_channel(wiphy, freq);
04f39047 SW	366	if (!c)
	367	return false;
	368
	369	/* check for radar flags */
	370	if ((prohibited_flags & c->flags & IEEE80211_CHAN_RADAR) &&
	371	(c->dfs_state != NL80211_DFS_AVAILABLE))
	372	return false;
	373
	374	/* check for the other flags */
	375	if (c->flags & prohibited_flags & ~IEEE80211_CHAN_RADAR)
3d9d1d66	376	return false;
9236d838 LR	377	}
9236d838 LR	378
3d9d1d66 JB	379	return true;
	380	}
	381
9f5e8f6e JB	382	bool cfg80211_chandef_usable(struct wiphy *wiphy,
	383	const struct cfg80211_chan_def *chandef,
	384	u32 prohibited_flags)
3d9d1d66	385	{
9f5e8f6e JB	386	struct ieee80211_sta_ht_cap *ht_cap;
	387	struct ieee80211_sta_vht_cap *vht_cap;
	388	u32 width, control_freq;
3d9d1d66	389
9f5e8f6e JB	390	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
9f5e8f6e JB	391	return false;
3d9d1d66	392
9f5e8f6e JB	393	ht_cap = &wiphy->bands[chandef->chan->band]->ht_cap;
9f5e8f6e JB	394	vht_cap = &wiphy->bands[chandef->chan->band]->vht_cap;
3d9d1d66	395
9f5e8f6e	396	control_freq = chandef->chan->center_freq;
9236d838	397
3d9d1d66	398	switch (chandef->width) {
2f301ab2 SW	399	case NL80211_CHAN_WIDTH_5:
	400	width = 5;
	401	break;
	402	case NL80211_CHAN_WIDTH_10:
	403	width = 10;
	404	break;
3d9d1d66	405	case NL80211_CHAN_WIDTH_20:
9f5e8f6e JB	406	if (!ht_cap->ht_supported)
	407	return false;
	408	case NL80211_CHAN_WIDTH_20_NOHT:
3d9d1d66 JB	409	width = 20;
	410	break;
	411	case NL80211_CHAN_WIDTH_40:
	412	width = 40;
9f5e8f6e JB	413	if (!ht_cap->ht_supported)
	414	return false;
	415	if (!(ht_cap->cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) \|\|
	416	ht_cap->cap & IEEE80211_HT_CAP_40MHZ_INTOLERANT)
	417	return false;
	418	if (chandef->center_freq1 < control_freq &&
	419	chandef->chan->flags & IEEE80211_CHAN_NO_HT40MINUS)
	420	return false;
	421	if (chandef->center_freq1 > control_freq &&
	422	chandef->chan->flags & IEEE80211_CHAN_NO_HT40PLUS)
	423	return false;
3d9d1d66	424	break;
3d9d1d66	425	case NL80211_CHAN_WIDTH_80P80:
9f5e8f6e JB	426	if (!(vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ))
	427	return false;
	428	case NL80211_CHAN_WIDTH_80:
	429	if (!vht_cap->vht_supported)
	430	return false;
c7a6ee27	431	prohibited_flags \|= IEEE80211_CHAN_NO_80MHZ;
3d9d1d66 JB	432	width = 80;
	433	break;
	434	case NL80211_CHAN_WIDTH_160:
9f5e8f6e JB	435	if (!vht_cap->vht_supported)
	436	return false;
	437	if (!(vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ))
	438	return false;
c7a6ee27	439	prohibited_flags \|= IEEE80211_CHAN_NO_160MHZ;
3d9d1d66 JB	440	width = 160;
	441	break;
	442	default:
	443	WARN_ON_ONCE(1);
9236d838	444	return false;
4ee3e063	445	}
3d9d1d66	446
c7a6ee27 JB	447	/*
	448	* TODO: What if there are only certain 80/160/80+80 MHz channels
	449	* allowed by the driver, or only certain combinations?
	450	* For 40 MHz the driver can set the NO_HT40 flags, but for
	451	* 80/160 MHz and in particular 80+80 MHz this isn't really
	452	* feasible and we only have NO_80MHZ/NO_160MHZ so far but
	453	* no way to cover 80+80 MHz or more complex restrictions.
	454	* Note that such restrictions also need to be advertised to
	455	* userspace, for example for P2P channel selection.
	456	*/
9f5e8f6e	457
a6662dba JB	458	if (width > 20)
	459	prohibited_flags \|= IEEE80211_CHAN_NO_OFDM;
	460
2f301ab2 SW	461	/* 5 and 10 MHz are only defined for the OFDM PHY */
	462	if (width < 20)
	463	prohibited_flags \|= IEEE80211_CHAN_NO_OFDM;
	464
	465
9f5e8f6e JB	466	if (!cfg80211_secondary_chans_ok(wiphy, chandef->center_freq1,
	467	width, prohibited_flags))
	468	return false;
	469
	470	if (!chandef->center_freq2)
	471	return true;
	472	return cfg80211_secondary_chans_ok(wiphy, chandef->center_freq2,
	473	width, prohibited_flags);
	474	}
	475	EXPORT_SYMBOL(cfg80211_chandef_usable);
	476
	477	bool cfg80211_reg_can_beacon(struct wiphy *wiphy,
	478	struct cfg80211_chan_def *chandef)
	479	{
	480	bool res;
	481
	482	trace_cfg80211_reg_can_beacon(wiphy, chandef);
3d9d1d66	483
9f5e8f6e JB	484	res = cfg80211_chandef_usable(wiphy, chandef,
9f5e8f6e JB	485	IEEE80211_CHAN_DISABLED \|
8fe02e16	486	IEEE80211_CHAN_NO_IR \|
9f5e8f6e	487	IEEE80211_CHAN_RADAR);
3d9d1d66 JB	488
	489	trace_cfg80211_return_bool(res);
	490	return res;
9236d838	491	}
683b6d3b	492	EXPORT_SYMBOL(cfg80211_reg_can_beacon);
9236d838	493
e8c9bd5b	494	int cfg80211_set_monitor_channel(struct cfg80211_registered_device *rdev,
683b6d3b	495	struct cfg80211_chan_def *chandef)
9588bbd5	496	{
e8c9bd5b	497	if (!rdev->ops->set_monitor_channel)
9588bbd5	498	return -EOPNOTSUPP;
4f03c1ed MK	499	if (!cfg80211_has_monitors_only(rdev))
4f03c1ed MK	500	return -EBUSY;
9588bbd5	501
683b6d3b	502	return rdev_set_monitor_channel(rdev, chandef);
59bbb6f7	503	}
26ab9a0c MK	504
26ab9a0c MK	505	void
8e95ea49	506	cfg80211_get_chan_state(struct wireless_dev *wdev,
26ab9a0c MK	507	struct ieee80211_channel **chan,
	508	enum cfg80211_chan_mode *chanmode)
	509	{
	510	*chan = NULL;
	511	*chanmode = CHAN_MODE_UNDEFINED;
	512
26ab9a0c MK	513	ASSERT_WDEV_LOCK(wdev);
26ab9a0c MK	514
98104fde	515	if (wdev->netdev && !netif_running(wdev->netdev))
26ab9a0c MK	516	return;
	517
	518	switch (wdev->iftype) {
	519	case NL80211_IFTYPE_ADHOC:
	520	if (wdev->current_bss) {
	521	*chan = wdev->current_bss->pub.channel;
5336fa88 SW	522	*chanmode = (wdev->ibss_fixed &&
5336fa88 SW	523	!wdev->ibss_dfs_possible)
26ab9a0c MK	524	? CHAN_MODE_SHARED
	525	: CHAN_MODE_EXCLUSIVE;
	526	return;
	527	}
	528	case NL80211_IFTYPE_STATION:
	529	case NL80211_IFTYPE_P2P_CLIENT:
	530	if (wdev->current_bss) {
	531	*chan = wdev->current_bss->pub.channel;
	532	*chanmode = CHAN_MODE_SHARED;
	533	return;
	534	}
	535	break;
	536	case NL80211_IFTYPE_AP:
	537	case NL80211_IFTYPE_P2P_GO:
04f39047 SW	538	if (wdev->cac_started) {
	539	*chan = wdev->channel;
	540	*chanmode = CHAN_MODE_SHARED;
	541	} else if (wdev->beacon_interval) {
f53594a0 FF	542	*chan = wdev->channel;
	543	*chanmode = CHAN_MODE_SHARED;
	544	}
	545	return;
26ab9a0c	546	case NL80211_IFTYPE_MESH_POINT:
f53594a0 FF	547	if (wdev->mesh_id_len) {
	548	*chan = wdev->channel;
	549	*chanmode = CHAN_MODE_SHARED;
	550	}
26ab9a0c MK	551	return;
	552	case NL80211_IFTYPE_MONITOR:
	553	case NL80211_IFTYPE_AP_VLAN:
	554	case NL80211_IFTYPE_WDS:
	555	/* these interface types don't really have a channel */
	556	return;
98104fde JB	557	case NL80211_IFTYPE_P2P_DEVICE:
	558	if (wdev->wiphy->features &
	559	NL80211_FEATURE_P2P_DEVICE_NEEDS_CHANNEL)
	560	*chanmode = CHAN_MODE_EXCLUSIVE;
	561	return;
26ab9a0c MK	562	case NL80211_IFTYPE_UNSPECIFIED:
	563	case NUM_NL80211_IFTYPES:
	564	WARN_ON(1);
	565	}
	566
	567	return;
	568	}