mac80211: move channel switch code

The channel switch code is currently in the spectrum
management file, where arguably it belongs. However,
it is for managed mode only and uses the structures
for that mode only so having it in a more generic
file can be confusing. Additionally, my next patch
gets simpler with the code here.

When/if we ever implement this for IBSS or mesh then
we will need to rework the structures it uses anyway
at which point we could move the code back.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 98 insertions, 1 deletions

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 47bc303..41f3c1f 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -486,6 +486,103 @@ void ieee80211_send_nullfunc(struct ieee80211_local *local,
 	ieee80211_tx_skb(sdata, skb, 0);
 }
 
+/* spectrum management related things */
+static void ieee80211_chswitch_work(struct work_struct *work)
+{
+	struct ieee80211_sub_if_data *sdata =
+		container_of(work, struct ieee80211_sub_if_data, u.mgd.chswitch_work);
+	struct ieee80211_bss *bss;
+	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
+
+	if (!netif_running(sdata->dev))
+		return;
+
+	bss = ieee80211_rx_bss_get(sdata->local, ifmgd->bssid,
+				   sdata->local->hw.conf.channel->center_freq,
+				   ifmgd->ssid, ifmgd->ssid_len);
+	if (!bss)
+		goto exit;
+
+	sdata->local->oper_channel = sdata->local->csa_channel;
+	/* XXX: shouldn't really modify cfg80211-owned data! */
+	if (!ieee80211_hw_config(sdata->local, IEEE80211_CONF_CHANGE_CHANNEL))
+		bss->cbss.channel = sdata->local->oper_channel;
+
+	ieee80211_rx_bss_put(sdata->local, bss);
+exit:
+	ifmgd->flags &= ~IEEE80211_STA_CSA_RECEIVED;
+	ieee80211_wake_queues_by_reason(&sdata->local->hw,
+					IEEE80211_QUEUE_STOP_REASON_CSA);
+}
+
+static void ieee80211_chswitch_timer(unsigned long data)
+{
+	struct ieee80211_sub_if_data *sdata =
+		(struct ieee80211_sub_if_data *) data;
+	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
+
+	queue_work(sdata->local->hw.workqueue, &ifmgd->chswitch_work);
+}
+
+void ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
+				      struct ieee80211_channel_sw_ie *sw_elem,
+				      struct ieee80211_bss *bss)
+{
+	struct ieee80211_channel *new_ch;
+	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
+	int new_freq = ieee80211_channel_to_frequency(sw_elem->new_ch_num);
+
+	if (ifmgd->state != IEEE80211_STA_MLME_ASSOCIATED)
+		return;
+
+	if (sdata->local->sw_scanning || sdata->local->hw_scanning)
+		return;
+
+	/* Disregard subsequent beacons if we are already running a timer
+	   processing a CSA */
+
+	if (ifmgd->flags & IEEE80211_STA_CSA_RECEIVED)
+		return;
+
+	new_ch = ieee80211_get_channel(sdata->local->hw.wiphy, new_freq);
+	if (!new_ch || new_ch->flags & IEEE80211_CHAN_DISABLED)
+		return;
+
+	sdata->local->csa_channel = new_ch;
+
+	if (sw_elem->count <= 1) {
+		queue_work(sdata->local->hw.workqueue, &ifmgd->chswitch_work);
+	} else {
+		ieee80211_stop_queues_by_reason(&sdata->local->hw,
+					IEEE80211_QUEUE_STOP_REASON_CSA);
+		ifmgd->flags |= IEEE80211_STA_CSA_RECEIVED;
+		mod_timer(&ifmgd->chswitch_timer,
+			  jiffies +
+			  msecs_to_jiffies(sw_elem->count *
+					   bss->cbss.beacon_interval));
+	}
+}
+
+static void ieee80211_handle_pwr_constr(struct ieee80211_sub_if_data *sdata,
+					u16 capab_info, u8 *pwr_constr_elem,
+					u8 pwr_constr_elem_len)
+{
+	struct ieee80211_conf *conf = &sdata->local->hw.conf;
+
+	if (!(capab_info & WLAN_CAPABILITY_SPECTRUM_MGMT))
+		return;
+
+	/* Power constraint IE length should be 1 octet */
+	if (pwr_constr_elem_len != 1)
+		return;
+
+	if ((*pwr_constr_elem <= conf->channel->max_power) &&
+	    (*pwr_constr_elem != sdata->local->power_constr_level)) {
+		sdata->local->power_constr_level = *pwr_constr_elem;
+		ieee80211_hw_config(sdata->local, 0);
+	}
+}
+
 /* powersave */
 static void ieee80211_enable_ps(struct ieee80211_local *local,
 				struct ieee80211_sub_if_data *sdata)
@@ -1736,7 +1833,7 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 	    (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN) == 0)) {
 		struct ieee80211_channel_sw_ie *sw_elem =
 			(struct ieee80211_channel_sw_ie *)elems->ch_switch_elem;
-		ieee80211_process_chanswitch(sdata, sw_elem, bss);
+		ieee80211_sta_process_chanswitch(sdata, sw_elem, bss);
 	}
 
 	ieee80211_rx_bss_put(local, bss);