It looks like channel change may fail in some cases and end up leaving
the hardware in state where it cannot transmit any frames. Add a
workaround to recover from this state if we detect that wiphy
selection is failing due to wiphys not leaving PAUSING state.
Signed-off-by: Jouni Malinen <jouni.malinen@xxxxxxxxxxx>
---
drivers/net/wireless/ath9k/ath9k.h | 4 +++
drivers/net/wireless/ath9k/main.c | 4 +--
drivers/net/wireless/ath9k/virtual.c | 37 +++++++++++++++++++++++++++++++++++
3 files changed, 43 insertions(+), 2 deletions(-)
--- wireless-testing.orig/drivers/net/wireless/ath9k/ath9k.h 2009-03-03 18:31:50.000000000 +0200
+++ wireless-testing/drivers/net/wireless/ath9k/ath9k.h 2009-03-03 18:32:06.000000000 +0200
@@ -567,6 +567,8 @@ struct ath_softc {
int chan_is_ht;
struct ath_wiphy *next_wiphy;
struct work_struct chan_work;
+ int wiphy_select_failures;
+ unsigned long wiphy_select_first_fail;
struct tasklet_struct intr_tq;
struct tasklet_struct bcon_tasklet;
@@ -665,6 +667,8 @@ void ath9k_update_ichannel(struct ath_so
void ath_update_chainmask(struct ath_softc *sc, int is_ht);
int ath_set_channel(struct ath_softc *sc, struct ieee80211_hw *hw,
struct ath9k_channel *hchan);
+void ath_radio_enable(struct ath_softc *sc);
+void ath_radio_disable(struct ath_softc *sc);
#ifdef CONFIG_PCI
int ath_pci_init(void);
--- wireless-testing.orig/drivers/net/wireless/ath9k/virtual.c 2009-03-03 18:31:50.000000000 +0200
+++ wireless-testing/drivers/net/wireless/ath9k/virtual.c 2009-03-03 18:32:06.000000000 +0200
@@ -432,6 +432,18 @@ int ath9k_wiphy_unpause(struct ath_wiphy
return ret;
}
+static void __ath9k_wiphy_mark_all_paused(struct ath_softc *sc)
+{
+ int i;
+ if (sc->pri_wiphy->state != ATH_WIPHY_INACTIVE)
+ sc->pri_wiphy->state = ATH_WIPHY_PAUSED;
+ for (i = 0; i < sc->num_sec_wiphy; i++) {
+ if (sc->sec_wiphy[i] &&
+ sc->sec_wiphy[i]->state != ATH_WIPHY_INACTIVE)
+ sc->sec_wiphy[i]->state = ATH_WIPHY_PAUSED;
+ }
+}
+
/* caller must hold wiphy_lock */
static void __ath9k_wiphy_pause_all(struct ath_softc *sc)
{
@@ -452,9 +464,34 @@ int ath9k_wiphy_select(struct ath_wiphy
spin_lock_bh(&sc->wiphy_lock);
if (__ath9k_wiphy_pausing(sc)) {
+ if (sc->wiphy_select_failures == 0)
+ sc->wiphy_select_first_fail = jiffies;
+ sc->wiphy_select_failures++;
+ if (time_after(jiffies, sc->wiphy_select_first_fail + HZ / 2))
+ {
+ printk(KERN_DEBUG "ath9k: Previous wiphy select timed "
+ "out; disable/enable hw to recover\n");
+ __ath9k_wiphy_mark_all_paused(sc);
+ /*
+ * TODO: this workaround to fix hardware is unlikely to
+ * be specific to virtual wiphy changes. It can happen
+ * on normal channel change, too, and as such, this
+ * should really be made more generic. For example,
+ * tricker radio disable/enable on GTT interrupt burst
+ * (say, 10 GTT interrupts received without any TX
+ * frame being completed)
+ */
+ spin_unlock_bh(&sc->wiphy_lock);
+ ath_radio_disable(sc);
+ ath_radio_enable(sc);
+ queue_work(aphy->sc->hw->workqueue,
+ &aphy->sc->chan_work);
+ return -EBUSY; /* previous select still in progress */
+ }
spin_unlock_bh(&sc->wiphy_lock);
return -EBUSY; /* previous select still in progress */
}
+ sc->wiphy_select_failures = 0;
/* Store the new channel */
sc->chan_idx = aphy->chan_idx;
--- wireless-testing.orig/drivers/net/wireless/ath9k/main.c 2009-03-03 18:32:00.000000000 +0200
+++ wireless-testing/drivers/net/wireless/ath9k/main.c 2009-03-03 18:32:06.000000000 +0200
@@ -1088,7 +1088,7 @@ fail:
/* Rfkill */
/*******************/
-static void ath_radio_enable(struct ath_softc *sc)
+void ath_radio_enable(struct ath_softc *sc)
{
struct ath_hw *ah = sc->sc_ah;
struct ieee80211_channel *channel = sc->hw->conf.channel;
@@ -1129,7 +1129,7 @@ static void ath_radio_enable(struct ath_
ath9k_ps_restore(sc);
}
-static void ath_radio_disable(struct ath_softc *sc)
+void ath_radio_disable(struct ath_softc *sc)
{
struct ath_hw *ah = sc->sc_ah;
struct ieee80211_channel *channel = sc->hw->conf.channel;
--
--
Jouni Malinen PGP id EFC895FA
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