From ccdfeab6536ae55d43436ffaae949afde6e962ca Mon Sep 17 00:00:00 2001 From: Jouni Malinen Date: Wed, 20 May 2009 21:59:08 +0300 Subject: [PATCH] ath9k: Update Beacon timers based on timestamp from the AP Some APs seem to drift away from the expected TBTT (timestamp % beacon_int_in_usec differs quite a bit from zero) which can result in us waking up way too early to receive a Beacon frame. In order to work around this, re-configure the Beacon timers after having received a Beacon frame from the AP (i.e., when we know the offset between the expected TBTT and the actual time the AP is sending out the Beacon frame). Signed-off-by: Jouni Malinen Signed-off-by: John W. Linville --- drivers/net/wireless/ath/ath9k/ath9k.h | 1 + drivers/net/wireless/ath/ath9k/main.c | 9 ++++++++- drivers/net/wireless/ath/ath9k/recv.c | 7 +++++++ 3 files changed, 16 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h index 0d4ac43f6d91..796a3adffea0 100644 --- a/drivers/net/wireless/ath/ath9k/ath9k.h +++ b/drivers/net/wireless/ath/ath9k/ath9k.h @@ -518,6 +518,7 @@ struct ath_rfkill { #define SC_OP_WAIT_FOR_CAB BIT(16) #define SC_OP_WAIT_FOR_PSPOLL_DATA BIT(17) #define SC_OP_WAIT_FOR_TX_ACK BIT(18) +#define SC_OP_BEACON_SYNC BIT(19) struct ath_bus_ops { void (*read_cachesize)(struct ath_softc *sc, int *csz); diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c index 5759c9465029..61da08a1648c 100644 --- a/drivers/net/wireless/ath/ath9k/main.c +++ b/drivers/net/wireless/ath/ath9k/main.c @@ -487,7 +487,7 @@ static void ath9k_tasklet(unsigned long data) * the next Beacon. */ DPRINTF(sc, ATH_DBG_PS, "TSFOOR - Sync with next Beacon\n"); - sc->sc_flags |= SC_OP_WAIT_FOR_BEACON; + sc->sc_flags |= SC_OP_WAIT_FOR_BEACON | SC_OP_BEACON_SYNC; } /* re-enable hardware interrupt */ @@ -914,6 +914,13 @@ static void ath9k_bss_assoc_info(struct ath_softc *sc, if (avp->av_opmode == NL80211_IFTYPE_STATION) { sc->curaid = bss_conf->aid; ath9k_hw_write_associd(sc); + + /* + * Request a re-configuration of Beacon related timers + * on the receipt of the first Beacon frame (i.e., + * after time sync with the AP). + */ + sc->sc_flags |= SC_OP_BEACON_SYNC; } /* Configure the beacon */ diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c index 5e046b58ad93..5014a19b0f75 100644 --- a/drivers/net/wireless/ath/ath9k/recv.c +++ b/drivers/net/wireless/ath/ath9k/recv.c @@ -521,6 +521,13 @@ static void ath_rx_ps_beacon(struct ath_softc *sc, struct sk_buff *skb) if (memcmp(sc->curbssid, mgmt->bssid, ETH_ALEN) != 0) return; /* not from our current AP */ + if (sc->sc_flags & SC_OP_BEACON_SYNC) { + sc->sc_flags &= ~SC_OP_BEACON_SYNC; + DPRINTF(sc, ATH_DBG_PS, "Reconfigure Beacon timers based on " + "timestamp from the AP\n"); + ath_beacon_config(sc, NULL); + } + if (!(sc->hw->conf.flags & IEEE80211_CONF_PS)) { /* We are not in PS mode anymore; remain awake */ DPRINTF(sc, ATH_DBG_PS, "Not in PS mode anymore, remain " -- GitLab