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_fixed_channel(struct cfg80211_registered_device *rdev,
14 struct wireless_dev *for_wdev)
16 struct wireless_dev *wdev;
17 struct ieee80211_channel *result = NULL;
19 WARN_ON(!mutex_is_locked(&rdev->devlist_mtx));
21 list_for_each_entry(wdev, &rdev->netdev_list, list) {
26 * Lock manually to tell lockdep about allowed
27 * nesting here if for_wdev->mtx is held already.
28 * This is ok as it's all under the rdev devlist
29 * mutex and as such can only be done once at any
32 mutex_lock_nested(&wdev->mtx, SINGLE_DEPTH_NESTING);
33 if (wdev->current_bss)
34 result = wdev->current_bss->pub.channel;
44 int rdev_set_freq(struct cfg80211_registered_device *rdev,
45 int freq, enum nl80211_channel_type channel_type)
47 struct ieee80211_channel *chan;
48 struct ieee80211_sta_ht_cap *ht_cap;
51 if (rdev_fixed_channel(rdev, NULL))
54 if (!rdev->ops->set_channel)
57 chan = ieee80211_get_channel(&rdev->wiphy, freq);
59 /* Primary channel not allowed */
60 if (!chan || chan->flags & IEEE80211_CHAN_DISABLED)
63 if (channel_type == NL80211_CHAN_HT40MINUS &&
64 chan->flags & IEEE80211_CHAN_NO_HT40MINUS)
66 else if (channel_type == NL80211_CHAN_HT40PLUS &&
67 chan->flags & IEEE80211_CHAN_NO_HT40PLUS)
70 ht_cap = &rdev->wiphy.bands[chan->band]->ht_cap;
72 if (channel_type != NL80211_CHAN_NO_HT) {
73 if (!ht_cap->ht_supported)
76 if (!(ht_cap->cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) ||
77 ht_cap->cap & IEEE80211_HT_CAP_40MHZ_INTOLERANT)
81 result = rdev->ops->set_channel(&rdev->wiphy, chan, channel_type);