2 * This file contains helper code to handle channel
3 * settings and keeping track of what is possible at
6 * Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
9 #include <linux/export.h>
10 #include <net/cfg80211.h>
13 struct ieee80211_channel *
14 rdev_freq_to_chan(struct cfg80211_registered_device *rdev,
15 int freq, enum nl80211_channel_type channel_type)
17 struct ieee80211_channel *chan;
18 struct ieee80211_sta_ht_cap *ht_cap;
20 chan = ieee80211_get_channel(&rdev->wiphy, freq);
22 /* Primary channel not allowed */
23 if (!chan || chan->flags & IEEE80211_CHAN_DISABLED)
26 if (channel_type == NL80211_CHAN_HT40MINUS &&
27 chan->flags & IEEE80211_CHAN_NO_HT40MINUS)
29 else if (channel_type == NL80211_CHAN_HT40PLUS &&
30 chan->flags & IEEE80211_CHAN_NO_HT40PLUS)
33 ht_cap = &rdev->wiphy.bands[chan->band]->ht_cap;
35 if (channel_type != NL80211_CHAN_NO_HT) {
36 if (!ht_cap->ht_supported)
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))
48 bool cfg80211_can_beacon_sec_chan(struct wiphy *wiphy,
49 struct ieee80211_channel *chan,
50 enum nl80211_channel_type channel_type)
52 struct ieee80211_channel *sec_chan;
55 switch (channel_type) {
56 case NL80211_CHAN_HT40PLUS:
59 case NL80211_CHAN_HT40MINUS:
66 sec_chan = ieee80211_get_channel(wiphy, chan->center_freq + diff);
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))
79 EXPORT_SYMBOL(cfg80211_can_beacon_sec_chan);
81 int cfg80211_set_freq(struct cfg80211_registered_device *rdev,
82 struct wireless_dev *wdev, int freq,
83 enum nl80211_channel_type channel_type)
85 struct ieee80211_channel *chan;
88 if (wdev && wdev->iftype == NL80211_IFTYPE_MONITOR)
92 ASSERT_WDEV_LOCK(wdev);
94 if (!netif_running(wdev->netdev))
98 if (!rdev->ops->set_channel)
101 chan = rdev_freq_to_chan(rdev, freq, channel_type);
105 /* Both channels should be able to initiate communication */
106 if (wdev && (wdev->iftype == NL80211_IFTYPE_ADHOC ||
107 wdev->iftype == NL80211_IFTYPE_AP ||
108 wdev->iftype == NL80211_IFTYPE_AP_VLAN ||
109 wdev->iftype == NL80211_IFTYPE_MESH_POINT ||
110 wdev->iftype == NL80211_IFTYPE_P2P_GO)) {
111 switch (channel_type) {
112 case NL80211_CHAN_HT40PLUS:
113 case NL80211_CHAN_HT40MINUS:
114 if (!cfg80211_can_beacon_sec_chan(&rdev->wiphy, chan,
117 "cfg80211: Secondary channel not "
118 "allowed to initiate communication\n");
127 result = rdev->ops->set_channel(&rdev->wiphy,
128 wdev ? wdev->netdev : NULL,
134 wdev->channel = chan;