brcmfmac: call brcmf_cfg80211_detach() after removal of interfaces

Instead of calling brcmf_cfg80211_detach() in brcmf_del_if() when
deleting the primary interface, call it in brcmf_detach() after
deleting all interfaces.
Reviewed-by: NHante Meuleman <meuleman@broadcom.com>
Reviewed-by: NPieter-Paul Giesberts <pieterpg@broadcom.com>
Signed-off-by: NArend van Spriel <arend@broadcom.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

drivers/net/wireless/brcm80211/brcmfmac/dhd_linux.c

@@ -859,8 +859,6 @@ void brcmf_del_if(struct brcmf_pub *drvr, s32 bssidx)
 		}
 		/* unregister will take care of freeing it */
 		unregister_netdev(ifp->ndev);
-		if (bssidx == 0)
-			brcmf_cfg80211_detach(drvr->config);
 	} else {
 		kfree(ifp);
 	}
@@ -963,8 +961,7 @@ int brcmf_bus_start(struct device *dev)
 fail:
 	if (ret < 0) {
 		brcmf_err("failed: %d\n", ret);
-		if (drvr->config)
-			brcmf_cfg80211_detach(drvr->config);
+		brcmf_cfg80211_detach(drvr->config);
 		if (drvr->fws) {
 			brcmf_fws_del_interface(ifp);
 			brcmf_fws_deinit(drvr);
@@ -1039,6 +1036,8 @@ void brcmf_detach(struct device *dev)
 			brcmf_del_if(drvr, i);
 		}
 
+	brcmf_cfg80211_detach(drvr->config);
+
 	brcmf_bus_detach(drvr);
 
 	brcmf_proto_detach(drvr);

drivers/net/wireless/brcm80211/brcmfmac/wl_cfg80211.c

@@ -4975,6 +4975,9 @@ struct brcmf_cfg80211_info *brcmf_cfg80211_attach(struct brcmf_pub *drvr,
 
 void brcmf_cfg80211_detach(struct brcmf_cfg80211_info *cfg)
 {
+	if (!cfg)
+		return;
+
 	WARN_ON(!list_empty(&cfg->vif_list));
 	wiphy_unregister(cfg->wiphy);
 	brcmf_btcoex_detach(cfg);