90 lines
2.1 KiB
C
90 lines
2.1 KiB
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 <net/cfg80211.h>
|
|
#include "core.h"
|
|
|
|
struct ieee80211_channel *
|
|
rdev_fixed_channel(struct cfg80211_registered_device *rdev,
|
|
struct wireless_dev *for_wdev)
|
|
{
|
|
struct wireless_dev *wdev;
|
|
struct ieee80211_channel *result = NULL;
|
|
|
|
WARN_ON(!mutex_is_locked(&rdev->devlist_mtx));
|
|
|
|
list_for_each_entry(wdev, &rdev->netdev_list, list) {
|
|
if (wdev == for_wdev)
|
|
continue;
|
|
|
|
/*
|
|
* Lock manually to tell lockdep about allowed
|
|
* nesting here if for_wdev->mtx is held already.
|
|
* This is ok as it's all under the rdev devlist
|
|
* mutex and as such can only be done once at any
|
|
* given time.
|
|
*/
|
|
mutex_lock_nested(&wdev->mtx, SINGLE_DEPTH_NESTING);
|
|
if (wdev->current_bss)
|
|
result = wdev->current_bss->pub.channel;
|
|
wdev_unlock(wdev);
|
|
|
|
if (result)
|
|
break;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
int rdev_set_freq(struct cfg80211_registered_device *rdev,
|
|
struct wireless_dev *for_wdev,
|
|
int freq, enum nl80211_channel_type channel_type)
|
|
{
|
|
struct ieee80211_channel *chan;
|
|
struct ieee80211_sta_ht_cap *ht_cap;
|
|
int result;
|
|
|
|
if (rdev_fixed_channel(rdev, for_wdev))
|
|
return -EBUSY;
|
|
|
|
if (!rdev->ops->set_channel)
|
|
return -EOPNOTSUPP;
|
|
|
|
chan = ieee80211_get_channel(&rdev->wiphy, freq);
|
|
|
|
/* Primary channel not allowed */
|
|
if (!chan || chan->flags & IEEE80211_CHAN_DISABLED)
|
|
return -EINVAL;
|
|
|
|
if (channel_type == NL80211_CHAN_HT40MINUS &&
|
|
chan->flags & IEEE80211_CHAN_NO_HT40MINUS)
|
|
return -EINVAL;
|
|
else if (channel_type == NL80211_CHAN_HT40PLUS &&
|
|
chan->flags & IEEE80211_CHAN_NO_HT40PLUS)
|
|
return -EINVAL;
|
|
|
|
ht_cap = &rdev->wiphy.bands[chan->band]->ht_cap;
|
|
|
|
if (channel_type != NL80211_CHAN_NO_HT) {
|
|
if (!ht_cap->ht_supported)
|
|
return -EINVAL;
|
|
|
|
if (!(ht_cap->cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) ||
|
|
ht_cap->cap & IEEE80211_HT_CAP_40MHZ_INTOLERANT)
|
|
return -EINVAL;
|
|
}
|
|
|
|
result = rdev->ops->set_channel(&rdev->wiphy, chan, channel_type);
|
|
if (result)
|
|
return result;
|
|
|
|
rdev->channel = chan;
|
|
|
|
return 0;
|
|
}
|