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 <net/cfg80211.h>
12 struct ieee80211_channel *
13 rdev_freq_to_chan(struct cfg80211_registered_device *rdev,
14 int freq, enum nl80211_channel_type channel_type)
16 struct ieee80211_channel *chan;
17 struct ieee80211_sta_ht_cap *ht_cap;
19 chan = ieee80211_get_channel(&rdev->wiphy, freq);
21 /* Primary channel not allowed */
22 if (!chan || chan->flags & IEEE80211_CHAN_DISABLED)
25 if (channel_type == NL80211_CHAN_HT40MINUS &&
26 chan->flags & IEEE80211_CHAN_NO_HT40MINUS)
28 else if (channel_type == NL80211_CHAN_HT40PLUS &&
29 chan->flags & IEEE80211_CHAN_NO_HT40PLUS)
32 ht_cap = &rdev->wiphy.bands[chan->band]->ht_cap;
34 if (channel_type != NL80211_CHAN_NO_HT) {
35 if (!ht_cap->ht_supported)
38 if (channel_type != NL80211_CHAN_HT20 &&
39 (!(ht_cap->cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) ||
40 ht_cap->cap & IEEE80211_HT_CAP_40MHZ_INTOLERANT))
47 static bool can_beacon_sec_chan(struct wiphy *wiphy,
48 struct ieee80211_channel *chan,
49 enum nl80211_channel_type channel_type)
51 struct ieee80211_channel *sec_chan;
54 switch (channel_type) {
55 case NL80211_CHAN_HT40PLUS:
57 case NL80211_CHAN_HT40MINUS:
63 sec_chan = ieee80211_get_channel(wiphy, chan->center_freq + diff);
67 /* we'll need a DFS capability later */
68 if (sec_chan->flags & (IEEE80211_CHAN_DISABLED |
69 IEEE80211_CHAN_PASSIVE_SCAN |
70 IEEE80211_CHAN_NO_IBSS |
71 IEEE80211_CHAN_RADAR))
77 int cfg80211_set_freq(struct cfg80211_registered_device *rdev,
78 struct wireless_dev *wdev, int freq,
79 enum nl80211_channel_type channel_type)
81 struct ieee80211_channel *chan;
84 if (wdev && wdev->iftype == NL80211_IFTYPE_MONITOR)
88 ASSERT_WDEV_LOCK(wdev);
90 if (!netif_running(wdev->netdev))
94 if (!rdev->ops->set_channel)
97 chan = rdev_freq_to_chan(rdev, freq, channel_type);
101 /* Both channels should be able to initiate communication */
102 if (wdev && (wdev->iftype == NL80211_IFTYPE_ADHOC ||
103 wdev->iftype == NL80211_IFTYPE_AP ||
104 wdev->iftype == NL80211_IFTYPE_AP_VLAN ||
105 wdev->iftype == NL80211_IFTYPE_MESH_POINT ||
106 wdev->iftype == NL80211_IFTYPE_P2P_GO)) {
107 switch (channel_type) {
108 case NL80211_CHAN_HT40PLUS:
109 case NL80211_CHAN_HT40MINUS:
110 if (!can_beacon_sec_chan(&rdev->wiphy, chan,
113 "cfg80211: Secondary channel not "
114 "allowed to initiate communication\n");
123 result = rdev->ops->set_channel(&rdev->wiphy,
124 wdev ? wdev->netdev : NULL,
130 wdev->channel = chan;