net/wireless/chan.c - kernel/msm-4.9 - Gitiles

 /*
  * 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_chan_def_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_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;
 		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;
 }

 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);
 	}
 }

 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;

 	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);

 bool cfg80211_secondary_chans_ok(struct wiphy *wiphy,
 				 u32 center_freq, u32 bandwidth,
 				 u32 prohibited_flags)
 {
 	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 & prohibited_flags)
 			return false;
 	}

 	return true;
 }

 static bool cfg80211_check_beacon_chans(struct wiphy *wiphy,
 					u32 center_freq, u32 bw)
 {
 	return cfg80211_secondary_chans_ok(wiphy, center_freq, bw,
 					   IEEE80211_CHAN_DISABLED |
 					   IEEE80211_CHAN_PASSIVE_SCAN |
 					   IEEE80211_CHAN_NO_IBSS |
 					   IEEE80211_CHAN_RADAR);
 }

 bool cfg80211_reg_can_beacon(struct wiphy *wiphy,
 			     struct cfg80211_chan_def *chandef)
 {
 	u32 width;
 	bool res;

 	trace_cfg80211_reg_can_beacon(wiphy, chandef);

 	if (WARN_ON(!cfg80211_chan_def_valid(chandef))) {
 		trace_cfg80211_return_bool(false);
 		return false;
 	}

 	switch (chandef->width) {
 	case NL80211_CHAN_WIDTH_20_NOHT:
 	case NL80211_CHAN_WIDTH_20:
 		width = 20;
 		break;
 	case NL80211_CHAN_WIDTH_40:
 		width = 40;
 		break;
 	case NL80211_CHAN_WIDTH_80:
 	case NL80211_CHAN_WIDTH_80P80:
 		width = 80;
 		break;
 	case NL80211_CHAN_WIDTH_160:
 		width = 160;
 		break;
 	default:
 		WARN_ON_ONCE(1);
 		trace_cfg80211_return_bool(false);
 		return false;
 	}

 	res = cfg80211_check_beacon_chans(wiphy, chandef->center_freq1, width);

 	if (res && chandef->center_freq2)
 		res = cfg80211_check_beacon_chans(wiphy, chandef->center_freq2,
 						  width);

 	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
 				  ? 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->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;
 }
	/*
	* 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_chan_def_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_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;
	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;
	}

	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);
	}
	}

	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;

	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);

	bool cfg80211_secondary_chans_ok(struct wiphy *wiphy,
	u32 center_freq, u32 bandwidth,
	u32 prohibited_flags)
	{
	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 & prohibited_flags)
	return false;
	}

	return true;
	}

	static bool cfg80211_check_beacon_chans(struct wiphy *wiphy,
	u32 center_freq, u32 bw)
	{
	return cfg80211_secondary_chans_ok(wiphy, center_freq, bw,
	IEEE80211_CHAN_DISABLED \|
	IEEE80211_CHAN_PASSIVE_SCAN \|
	IEEE80211_CHAN_NO_IBSS \|
	IEEE80211_CHAN_RADAR);
	}

	bool cfg80211_reg_can_beacon(struct wiphy *wiphy,
	struct cfg80211_chan_def *chandef)
	{
	u32 width;
	bool res;

	trace_cfg80211_reg_can_beacon(wiphy, chandef);

	if (WARN_ON(!cfg80211_chan_def_valid(chandef))) {
	trace_cfg80211_return_bool(false);
	return false;
	}

	switch (chandef->width) {
	case NL80211_CHAN_WIDTH_20_NOHT:
	case NL80211_CHAN_WIDTH_20:
	width = 20;
	break;
	case NL80211_CHAN_WIDTH_40:
	width = 40;
	break;
	case NL80211_CHAN_WIDTH_80:
	case NL80211_CHAN_WIDTH_80P80:
	width = 80;
	break;
	case NL80211_CHAN_WIDTH_160:
	width = 160;
	break;
	default:
	WARN_ON_ONCE(1);
	trace_cfg80211_return_bool(false);
	return false;
	}

	res = cfg80211_check_beacon_chans(wiphy, chandef->center_freq1, width);

	if (res && chandef->center_freq2)
	res = cfg80211_check_beacon_chans(wiphy, chandef->center_freq2,
	width);

	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
	? 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->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;
	}