This adds support for iwm firmware's missed beacon notification.
With this, the driver will notice "dead air" when a laptop moves too far
away from the AP. It will automatically try to connect to another AP that
is closer, or again to the same AP when it moves back in range.
ok?
Index: if_iwm.c
===================================================================
RCS file: /cvs/src/sys/dev/pci/if_iwm.c,v
retrieving revision 1.184
diff -u -p -r1.184 if_iwm.c
--- if_iwm.c 28 May 2017 11:03:48 -0000 1.184
+++ if_iwm.c 30 May 2017 18:16:53 -0000
@@ -3535,6 +3535,34 @@ iwm_rx_tx_cmd(struct iwm_softc *sc, stru
}
}
+void
+iwm_rx_bmiss(struct iwm_softc *sc, struct iwm_rx_packet *pkt,
+ struct iwm_rx_data *data)
+{
+ struct ieee80211com *ic = &sc->sc_ic;
+ int bmiss_threshold = ic->ic_bmisstimeout / ic->ic_lintval;
+ struct iwm_missed_beacons_notif *mbn = (void *)pkt->data;
+
+ if ((ic->ic_opmode != IEEE80211_M_STA) ||
+ (ic->ic_state != IEEE80211_S_RUN))
+ return;
+
+ bus_dmamap_sync(sc->sc_dmat, data->map, sizeof(*pkt),
+ sizeof(*mbn), BUS_DMASYNC_POSTREAD);
+
+ if (mbn->consec_missed_beacons_since_last_rx > bmiss_threshold) {
+ /*
+ * Rather than go directly to scan state, try to send a
+ * directed probe request first. If that fails then the
+ * state machine will drop us into scanning after timing
+ * out waiting for a probe response.
+ */
+ IEEE80211_SEND_MGMT(ic, ic->ic_bss,
+ IEEE80211_FC0_SUBTYPE_PROBE_REQ, 0);
+ }
+
+}
+
int
iwm_binding_cmd(struct iwm_softc *sc, struct iwm_node *in, uint32_t action)
{
@@ -6566,7 +6594,7 @@ iwm_notif_intr(struct iwm_softc *sc)
break;
case IWM_MISSED_BEACONS_NOTIFICATION:
- /* OpenBSD does not provide ieee80211_beacon_miss() */
+ iwm_rx_bmiss(sc, pkt, data);
break;
case IWM_MFUART_LOAD_NOTIFICATION:
