wifi: mac80211: handle wider bandwidth OFDMA during CSA

During channel switch, track the AP configuration in the
chanreq, so that wider bandwidth OFDMA is taken into
account correctly, since multiple channel contexts may
be needed due to sharing not being possible due to
wider bandwidth OFDMA.

Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240506215543.b2c5a72dac1b.I69f65cb2e75d4a49a174b1aede68bf8ff0a3cab3@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/mlme.c

@@ -2517,8 +2517,13 @@ ieee80211_sta_process_chanswitch(struct ieee80211_link_data *link,
 		goto drop_connection;
 	}
 
+	link->csa.chanreq = csa_ie.chanreq;
+	if (link->u.mgd.conn.mode < IEEE80211_CONN_MODE_EHT ||
+	    sdata->vif.driver_flags & IEEE80211_VIF_IGNORE_OFDMA_WIDER_BW)
+		link->csa.chanreq.ap.chan = NULL;
+
 	if (chanctx) {
-		res = ieee80211_link_reserve_chanctx(link, &csa_ie.chanreq,
+		res = ieee80211_link_reserve_chanctx(link, &link->csa.chanreq,
 						     chanctx->mode, false);
 		if (res) {
 			link_info(link,
@@ -2529,7 +2534,6 @@ ieee80211_sta_process_chanswitch(struct ieee80211_link_data *link,
 	}
 
 	link->conf->csa_active = true;
-	link->csa.chanreq = csa_ie.chanreq;
 	link->u.mgd.csa.ignored_same_chan = false;
 	link->u.mgd.beacon_crc_valid = false;
 	link->u.mgd.csa.blocked_tx = csa_ie.mode;

net/mac80211/spectmgmt.c

@@ -9,7 +9,7 @@
  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
  * Copyright 2007-2008, Intel Corporation
  * Copyright 2008, Johannes Berg <johannes@sipsolutions.net>
- * Copyright (C) 2018, 2020, 2022-2023 Intel Corporation
+ * Copyright (C) 2018, 2020, 2022-2024 Intel Corporation
  */
 
 #include <linux/ieee80211.h>
@@ -366,6 +366,9 @@ int ieee80211_parse_ch_switch_ie(struct ieee80211_sub_if_data *sdata,
 		validate_chandef_by_ht_vht_oper(sdata, conn, vht_cap_info,
 						&new_chandef);
 
+	/* capture the AP chandef before (potential) downgrading */
+	csa_ie->chanreq.ap = new_chandef;
+
 	/* if data is there validate the bandwidth & use it */
 	if (new_chandef.chan) {
 		if (conn->bw_limit < IEEE80211_CONN_BW_LIMIT_320 &&