1 /* 2 * mac80211 - channel management 3 */ 4 5 #include <linux/nl80211.h> 6 #include <net/cfg80211.h> 7 #include "ieee80211_i.h" 8 9 static enum ieee80211_chan_mode 10 __ieee80211_get_channel_mode(struct ieee80211_local *local, 11 struct ieee80211_sub_if_data *ignore) 12 { 13 struct ieee80211_sub_if_data *sdata; 14 15 lockdep_assert_held(&local->iflist_mtx); 16 17 list_for_each_entry(sdata, &local->interfaces, list) { 18 if (sdata == ignore) 19 continue; 20 21 if (!ieee80211_sdata_running(sdata)) 22 continue; 23 24 switch (sdata->vif.type) { 25 case NL80211_IFTYPE_MONITOR: 26 continue; 27 case NL80211_IFTYPE_STATION: 28 if (!sdata->u.mgd.associated) 29 continue; 30 break; 31 case NL80211_IFTYPE_ADHOC: 32 if (!sdata->u.ibss.ssid_len) 33 continue; 34 if (!sdata->u.ibss.fixed_channel) 35 return CHAN_MODE_HOPPING; 36 break; 37 case NL80211_IFTYPE_AP_VLAN: 38 /* will also have _AP interface */ 39 continue; 40 case NL80211_IFTYPE_AP: 41 if (!sdata->u.ap.beacon) 42 continue; 43 break; 44 case NL80211_IFTYPE_MESH_POINT: 45 if (!sdata->wdev.mesh_id_len) 46 continue; 47 break; 48 default: 49 break; 50 } 51 52 return CHAN_MODE_FIXED; 53 } 54 55 return CHAN_MODE_UNDEFINED; 56 } 57 58 enum ieee80211_chan_mode 59 ieee80211_get_channel_mode(struct ieee80211_local *local, 60 struct ieee80211_sub_if_data *ignore) 61 { 62 enum ieee80211_chan_mode mode; 63 64 mutex_lock(&local->iflist_mtx); 65 mode = __ieee80211_get_channel_mode(local, ignore); 66 mutex_unlock(&local->iflist_mtx); 67 68 return mode; 69 } 70 71 bool ieee80211_set_channel_type(struct ieee80211_local *local, 72 struct ieee80211_sub_if_data *sdata, 73 enum nl80211_channel_type chantype) 74 { 75 struct ieee80211_sub_if_data *tmp; 76 enum nl80211_channel_type superchan = NL80211_CHAN_NO_HT; 77 bool result; 78 79 mutex_lock(&local->iflist_mtx); 80 81 list_for_each_entry(tmp, &local->interfaces, list) { 82 if (tmp == sdata) 83 continue; 84 85 if (!ieee80211_sdata_running(tmp)) 86 continue; 87 88 switch (tmp->vif.bss_conf.channel_type) { 89 case NL80211_CHAN_NO_HT: 90 case NL80211_CHAN_HT20: 91 if (superchan > tmp->vif.bss_conf.channel_type) 92 break; 93 94 superchan = tmp->vif.bss_conf.channel_type; 95 break; 96 case NL80211_CHAN_HT40PLUS: 97 WARN_ON(superchan == NL80211_CHAN_HT40MINUS); 98 superchan = NL80211_CHAN_HT40PLUS; 99 break; 100 case NL80211_CHAN_HT40MINUS: 101 WARN_ON(superchan == NL80211_CHAN_HT40PLUS); 102 superchan = NL80211_CHAN_HT40MINUS; 103 break; 104 } 105 } 106 107 switch (superchan) { 108 case NL80211_CHAN_NO_HT: 109 case NL80211_CHAN_HT20: 110 /* 111 * allow any change that doesn't go to no-HT 112 * (if it already is no-HT no change is needed) 113 */ 114 if (chantype == NL80211_CHAN_NO_HT) 115 break; 116 superchan = chantype; 117 break; 118 case NL80211_CHAN_HT40PLUS: 119 case NL80211_CHAN_HT40MINUS: 120 /* allow smaller bandwidth and same */ 121 if (chantype == NL80211_CHAN_NO_HT) 122 break; 123 if (chantype == NL80211_CHAN_HT20) 124 break; 125 if (superchan == chantype) 126 break; 127 result = false; 128 goto out; 129 } 130 131 local->_oper_channel_type = superchan; 132 133 if (sdata) 134 sdata->vif.bss_conf.channel_type = chantype; 135 136 result = true; 137 out: 138 mutex_unlock(&local->iflist_mtx); 139 140 return result; 141 } 142