brcmfmac: ignore IF event if it is a add for ifidx 0

Firmware fires IF event to add the primary interface but that
is already created in the driver.

Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Reviewed-by: Hante Meuleman <meuleman@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Franky Lin <frankyl@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

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

@@ -696,12 +696,17 @@ struct brcmf_if *brcmf_add_if(struct brcmf_pub *drvr, int ifidx, s32 bssidx,
 	 * in case we missed the BRCMF_E_IF_DEL event.
 	 */
 	if (ifp) {
-		brcmf_dbg(ERROR, "ERROR: netdev:%s already exists, try free & unregister\n",
+		brcmf_dbg(ERROR, "ERROR: netdev:%s already exists\n",
 			  ifp->ndev->name);
-		netif_stop_queue(ifp->ndev);
-		unregister_netdev(ifp->ndev);
-		free_netdev(ifp->ndev);
-		drvr->iflist[ifidx] = NULL;
+		if (ifidx) {
+			netif_stop_queue(ifp->ndev);
+			unregister_netdev(ifp->ndev);
+			free_netdev(ifp->ndev);
+			drvr->iflist[ifidx] = NULL;
+		} else {
+			brcmf_dbg(ERROR, "ignore IF event\n");
+			return ERR_PTR(-EINVAL);
+		}
 	}
 
 	/* Allocate netdev, including space for private structure */

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

@@ -402,7 +402,8 @@ int brcmf_fweh_register(struct brcmf_pub *drvr, enum brcmf_fweh_event_code code,
 		return -ENOSPC;
 	}
 	drvr->fweh.evt_handler[code] = handler;
-	brcmf_dbg(TRACE, "event handler registered for code %d\n", code);
+	brcmf_dbg(TRACE, "event handler registered for %s\n",
+		  brcmf_fweh_event_name(code));
 	return 0;
 }
 
@@ -415,7 +416,8 @@ int brcmf_fweh_register(struct brcmf_pub *drvr, enum brcmf_fweh_event_code code,
 void brcmf_fweh_unregister(struct brcmf_pub *drvr,
 			   enum brcmf_fweh_event_code code)
 {
-	brcmf_dbg(TRACE, "event handler cleared for code %d\n", code);
+	brcmf_dbg(TRACE, "event handler cleared for %s\n",
+		  brcmf_fweh_event_name(code));
 	drvr->fweh.evt_handler[code] = NULL;
 }
 
@@ -438,6 +440,7 @@ int brcmf_fweh_activate_events(struct brcmf_if *ifp)
 	}
 
 	/* want to handle IF event as well */
+	brcmf_dbg(EVENT, "enable event IF\n");
 	setbit(eventmask, BRCMF_E_IF);
 
 	err = brcmf_fil_iovar_data_set(ifp, "event_msgs",