[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"

struct ieee80211_channel *
rdev_freq_to_chan(struct cfg80211_registered_device *rdev,
		  int freq, enum nl80211_channel_type channel_type)
{
	struct ieee80211_channel *chan;
	struct ieee80211_sta_ht_cap *ht_cap;

	chan = ieee80211_get_channel(&rdev->wiphy, freq);

	/* Primary channel not allowed */
	if (!chan || chan->flags & IEEE80211_CHAN_DISABLED)
		return NULL;

	if (channel_type == NL80211_CHAN_HT40MINUS &&
	    chan->flags & IEEE80211_CHAN_NO_HT40MINUS)
		return NULL;
	else if (channel_type == NL80211_CHAN_HT40PLUS &&
		 chan->flags & IEEE80211_CHAN_NO_HT40PLUS)
		return NULL;

	ht_cap = &rdev->wiphy.bands[chan->band]->ht_cap;

	if (channel_type != NL80211_CHAN_NO_HT) {
		if (!ht_cap->ht_supported)
			return NULL;

		if (channel_type != NL80211_CHAN_HT20 &&
		    (!(ht_cap->cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) ||
		    ht_cap->cap & IEEE80211_HT_CAP_40MHZ_INTOLERANT))
			return NULL;
	}

	return chan;
}

bool cfg80211_can_beacon_sec_chan(struct wiphy *wiphy,
				  struct ieee80211_channel *chan,
				  enum nl80211_channel_type channel_type)
{
	struct ieee80211_channel *sec_chan;
	int diff;

	switch (channel_type) {
	case NL80211_CHAN_HT40PLUS:
		diff = 20;
		break;
	case NL80211_CHAN_HT40MINUS:
		diff = -20;
		break;
	default:
		return true;
	}

	sec_chan = ieee80211_get_channel(wiphy, chan->center_freq + diff);
	if (!sec_chan)
		return false;

	/* we'll need a DFS capability later */
	if (sec_chan->flags & (IEEE80211_CHAN_DISABLED |
			       IEEE80211_CHAN_PASSIVE_SCAN |
			       IEEE80211_CHAN_NO_IBSS |
			       IEEE80211_CHAN_RADAR))
		return false;

	return true;
}
EXPORT_SYMBOL(cfg80211_can_beacon_sec_chan);

int cfg80211_set_monitor_channel(struct cfg80211_registered_device *rdev,
				 int freq, enum nl80211_channel_type chantype)
{
	struct ieee80211_channel *chan;
	int err;

	if (!rdev->ops->set_monitor_channel)
		return -EOPNOTSUPP;
	if (!cfg80211_has_monitors_only(rdev))
		return -EBUSY;

	chan = rdev_freq_to_chan(rdev, freq, chantype);
	if (!chan)
		return -EINVAL;

	err = rdev->ops->set_monitor_channel(&rdev->wiphy, chan, chantype);
	if (!err) {
		rdev->monitor_channel = chan;
		rdev->monitor_channel_type = chantype;
	}

	return err;
}

void
cfg80211_get_chan_state(struct cfg80211_registered_device *rdev,
		        struct wireless_dev *wdev,
		        struct ieee80211_channel **chan,
		        enum cfg80211_chan_mode *chanmode)
{
	*chan = NULL;
	*chanmode = CHAN_MODE_UNDEFINED;

	ASSERT_RDEV_LOCK(rdev);
	ASSERT_WDEV_LOCK(wdev);

	if (!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:
	case NL80211_IFTYPE_MESH_POINT:
		*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_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>
	11	#include "core.h"
	12
9588bbd5 JM	13	struct ieee80211_channel *
9588bbd5 JM	14	rdev_freq_to_chan(struct cfg80211_registered_device *rdev,
59bbb6f7 JB	15	int freq, enum nl80211_channel_type channel_type)
	16	{
	17	struct ieee80211_channel *chan;
	18	struct ieee80211_sta_ht_cap *ht_cap;
59bbb6f7 JB	19
	20	chan = ieee80211_get_channel(&rdev->wiphy, freq);
	21
	22	/* Primary channel not allowed */
	23	if (!chan \|\| chan->flags & IEEE80211_CHAN_DISABLED)
9588bbd5	24	return NULL;
59bbb6f7 JB	25
	26	if (channel_type == NL80211_CHAN_HT40MINUS &&
	27	chan->flags & IEEE80211_CHAN_NO_HT40MINUS)
9588bbd5	28	return NULL;
59bbb6f7 JB	29	else if (channel_type == NL80211_CHAN_HT40PLUS &&
59bbb6f7 JB	30	chan->flags & IEEE80211_CHAN_NO_HT40PLUS)
9588bbd5	31	return NULL;
59bbb6f7 JB	32
	33	ht_cap = &rdev->wiphy.bands[chan->band]->ht_cap;
	34
	35	if (channel_type != NL80211_CHAN_NO_HT) {
	36	if (!ht_cap->ht_supported)
9588bbd5	37	return NULL;
59bbb6f7	38
aed8e1f9 HS	39	if (channel_type != NL80211_CHAN_HT20 &&
	40	(!(ht_cap->cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) \|\|
	41	ht_cap->cap & IEEE80211_HT_CAP_40MHZ_INTOLERANT))
9588bbd5	42	return NULL;
59bbb6f7 JB	43	}
59bbb6f7 JB	44
9588bbd5 JM	45	return chan;
	46	}
	47
294a20e0	48	bool cfg80211_can_beacon_sec_chan(struct wiphy *wiphy,
54858ee5 AS	49	struct ieee80211_channel *chan,
54858ee5 AS	50	enum nl80211_channel_type channel_type)
9236d838 LR	51	{
	52	struct ieee80211_channel *sec_chan;
	53	int diff;
	54
	55	switch (channel_type) {
	56	case NL80211_CHAN_HT40PLUS:
	57	diff = 20;
09a02fdb	58	break;
9236d838 LR	59	case NL80211_CHAN_HT40MINUS:
9236d838 LR	60	diff = -20;
09a02fdb	61	break;
9236d838	62	default:
d58e7e37	63	return true;
9236d838 LR	64	}
	65
	66	sec_chan = ieee80211_get_channel(wiphy, chan->center_freq + diff);
	67	if (!sec_chan)
	68	return false;
	69
	70	/* we'll need a DFS capability later */
	71	if (sec_chan->flags & (IEEE80211_CHAN_DISABLED \|
	72	IEEE80211_CHAN_PASSIVE_SCAN \|
	73	IEEE80211_CHAN_NO_IBSS \|
	74	IEEE80211_CHAN_RADAR))
	75	return false;
	76
	77	return true;
	78	}
54858ee5	79	EXPORT_SYMBOL(cfg80211_can_beacon_sec_chan);
9236d838	80
e8c9bd5b JB	81	int cfg80211_set_monitor_channel(struct cfg80211_registered_device *rdev,
e8c9bd5b JB	82	int freq, enum nl80211_channel_type chantype)
9588bbd5 JM	83	{
9588bbd5 JM	84	struct ieee80211_channel *chan;
b78e8cea	85	int err;
9588bbd5	86
e8c9bd5b	87	if (!rdev->ops->set_monitor_channel)
9588bbd5	88	return -EOPNOTSUPP;
4f03c1ed MK	89	if (!cfg80211_has_monitors_only(rdev))
4f03c1ed MK	90	return -EBUSY;
9588bbd5	91
e8c9bd5b	92	chan = rdev_freq_to_chan(rdev, freq, chantype);
9588bbd5 JM	93	if (!chan)
	94	return -EINVAL;
	95
b78e8cea MK	96	err = rdev->ops->set_monitor_channel(&rdev->wiphy, chan, chantype);
	97	if (!err) {
	98	rdev->monitor_channel = chan;
	99	rdev->monitor_channel_type = chantype;
	100	}
	101
	102	return err;
59bbb6f7	103	}
26ab9a0c MK	104
	105	void
	106	cfg80211_get_chan_state(struct cfg80211_registered_device *rdev,
	107	struct wireless_dev *wdev,
	108	struct ieee80211_channel **chan,
	109	enum cfg80211_chan_mode *chanmode)
	110	{
	111	*chan = NULL;
	112	*chanmode = CHAN_MODE_UNDEFINED;
	113
	114	ASSERT_RDEV_LOCK(rdev);
	115	ASSERT_WDEV_LOCK(wdev);
	116
	117	if (!netif_running(wdev->netdev))
	118	return;
	119
	120	switch (wdev->iftype) {
	121	case NL80211_IFTYPE_ADHOC:
	122	if (wdev->current_bss) {
	123	*chan = wdev->current_bss->pub.channel;
	124	*chanmode = wdev->ibss_fixed
	125	? CHAN_MODE_SHARED
	126	: CHAN_MODE_EXCLUSIVE;
	127	return;
	128	}
	129	case NL80211_IFTYPE_STATION:
	130	case NL80211_IFTYPE_P2P_CLIENT:
	131	if (wdev->current_bss) {
	132	*chan = wdev->current_bss->pub.channel;
	133	*chanmode = CHAN_MODE_SHARED;
	134	return;
	135	}
	136	break;
	137	case NL80211_IFTYPE_AP:
	138	case NL80211_IFTYPE_P2P_GO:
	139	case NL80211_IFTYPE_MESH_POINT:
	140	*chan = wdev->channel;
	141	*chanmode = CHAN_MODE_SHARED;
	142	return;
	143	case NL80211_IFTYPE_MONITOR:
	144	case NL80211_IFTYPE_AP_VLAN:
	145	case NL80211_IFTYPE_WDS:
	146	/* these interface types don't really have a channel */
	147	return;
	148	case NL80211_IFTYPE_UNSPECIFIED:
	149	case NUM_NL80211_IFTYPES:
	150	WARN_ON(1);
	151	}
	152
	153	return;
	154	}