3 files changed, 68 insertions, 10 deletions

diff --git a/drivers/net/wireless/ath9k/ath9k.h b/drivers/net/wireless/ath9k/ath9k.h
index 4fc054e4354f..983f53daa1cc 100644
--- a/drivers/net/wireless/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath9k/ath9k.h
@@ -633,6 +633,7 @@ struct ath_wiphy {
                 ATH_WIPHY_ACTIVE,
                 ATH_WIPHY_PAUSING,
                 ATH_WIPHY_PAUSED,
+                ATH_WIPHY_SCAN,
         } state;
         int chan_idx;
         int chan_is_ht;
@@ -716,5 +717,6 @@ void ath9k_wiphy_chan_work(struct work_struct *work);
 bool ath9k_wiphy_started(struct ath_softc *sc);
 void ath9k_wiphy_pause_all_forced(struct ath_softc *sc,
                                   struct ath_wiphy *selected);
+bool ath9k_wiphy_scanning(struct ath_softc *sc);
 
 #endif /* ATH9K_H */
diff --git a/drivers/net/wireless/ath9k/main.c b/drivers/net/wireless/ath9k/main.c
index bb6e1ddb4a57..626392241d43 100644
--- a/drivers/net/wireless/ath9k/main.c
+++ b/drivers/net/wireless/ath9k/main.c
@@ -2077,7 +2077,7 @@ static int ath9k_tx(struct ieee80211_hw *hw,
         struct ath_tx_control txctl;
         int hdrlen, padsize;
 
-        if (aphy->state != ATH_WIPHY_ACTIVE) {
+        if (aphy->state != ATH_WIPHY_ACTIVE && aphy->state != ATH_WIPHY_SCAN) {
                 printk(KERN_DEBUG "ath9k: %s: TX in unexpected wiphy state "
                        "%d\n", wiphy_name(hw->wiphy), aphy->state);
                 goto exit;
@@ -2348,14 +2348,16 @@ static int ath9k_config(struct ieee80211_hw *hw, u32 changed)
                 aphy->chan_idx = pos;
                 aphy->chan_is_ht = conf_is_ht(conf);
 
-                /* TODO: do not change operation channel immediately if there
-                 * are other virtual wiphys that use another channel. For now,
-                 * we do the change immediately to allow mac80211-operated scan
-                 * to work. Once the scan operation is moved into ath9k, we can
-                 * just move the current aphy in PAUSED state if the channel is
-                 * changed into something different from the current operation
-                 * channel. */
-                ath9k_wiphy_pause_all_forced(sc, aphy);
+                if (aphy->state == ATH_WIPHY_SCAN ||
+                    aphy->state == ATH_WIPHY_ACTIVE)
+                        ath9k_wiphy_pause_all_forced(sc, aphy);
+                else {
+                        /*
+                         * Do not change operational channel based on a paused
+                         * wiphy changes.
+                         */
+                        goto skip_chan_change;
+                }
 
                 DPRINTF(sc, ATH_DBG_CONFIG, "Set channel: %d MHz\n",
                         curchan->center_freq);
@@ -2372,6 +2374,7 @@ static int ath9k_config(struct ieee80211_hw *hw, u32 changed)
                 }
         }
 
+skip_chan_change:
         if (changed & IEEE80211_CONF_CHANGE_POWER)
                 sc->config.txpowlimit = 2 * conf->power_level;
 
@@ -2731,6 +2734,19 @@ static void ath9k_sw_scan_start(struct ieee80211_hw *hw)
         struct ath_wiphy *aphy = hw->priv;
         struct ath_softc *sc = aphy->sc;
 
+        if (ath9k_wiphy_scanning(sc)) {
+                printk(KERN_DEBUG "ath9k: Two wiphys trying to scan at the "
+                       "same time\n");
+                /*
+                 * Do not allow the concurrent scanning state for now. This
+                 * could be improved with scanning control moved into ath9k.
+                 */
+                return;
+        }
+
+        aphy->state = ATH_WIPHY_SCAN;
+        ath9k_wiphy_pause_all_forced(sc, aphy);
+
         mutex_lock(&sc->mutex);
         sc->sc_flags |= SC_OP_SCANNING;
         mutex_unlock(&sc->mutex);
@@ -2742,6 +2758,7 @@ static void ath9k_sw_scan_complete(struct ieee80211_hw *hw)
         struct ath_softc *sc = aphy->sc;
 
         mutex_lock(&sc->mutex);
+        aphy->state = ATH_WIPHY_ACTIVE;
         sc->sc_flags &= ~SC_OP_SCANNING;
         mutex_unlock(&sc->mutex);
 }
diff --git a/drivers/net/wireless/ath9k/virtual.c b/drivers/net/wireless/ath9k/virtual.c
index 913d2043d23e..2b545319408d 100644
--- a/drivers/net/wireless/ath9k/virtual.c
+++ b/drivers/net/wireless/ath9k/virtual.c
@@ -244,6 +244,28 @@ static bool ath9k_wiphy_pausing(struct ath_softc *sc)
         return ret;
 }
 
+static bool __ath9k_wiphy_scanning(struct ath_softc *sc)
+{
+        int i;
+        if (sc->pri_wiphy->state == ATH_WIPHY_SCAN)
+                return true;
+        for (i = 0; i < sc->num_sec_wiphy; i++) {
+                if (sc->sec_wiphy[i] &&
+                    sc->sec_wiphy[i]->state == ATH_WIPHY_SCAN)
+                        return true;
+        }
+        return false;
+}
+
+bool ath9k_wiphy_scanning(struct ath_softc *sc)
+{
+        bool ret;
+        spin_lock_bh(&sc->wiphy_lock);
+        ret = __ath9k_wiphy_scanning(sc);
+        spin_unlock_bh(&sc->wiphy_lock);
+        return ret;
+}
+
 static int __ath9k_wiphy_unpause(struct ath_wiphy *aphy);
 
 /* caller must hold wiphy_lock */
@@ -463,6 +485,16 @@ int ath9k_wiphy_select(struct ath_wiphy *aphy)
         bool now;
 
         spin_lock_bh(&sc->wiphy_lock);
+        if (__ath9k_wiphy_scanning(sc)) {
+                /*
+                 * For now, we are using mac80211 sw scan and it expects to
+                 * have full control over channel changes, so avoid wiphy
+                 * scheduling during a scan. This could be optimized if the
+                 * scanning control were moved into the driver.
+                 */
+                spin_unlock_bh(&sc->wiphy_lock);
+                return -EBUSY;
+        }
         if (__ath9k_wiphy_pausing(sc)) {
                 if (sc->wiphy_select_failures == 0)
                         sc->wiphy_select_first_fail = jiffies;
@@ -537,7 +569,14 @@ bool ath9k_wiphy_started(struct ath_softc *sc)
 static void ath9k_wiphy_pause_chan(struct ath_wiphy *aphy,
                                    struct ath_wiphy *selected)
 {
-        if (aphy->chan_idx == selected->chan_idx)
+        if (selected->state == ATH_WIPHY_SCAN) {
+                if (aphy == selected)
+                        return;
+                /*
+                 * Pause all other wiphys for the duration of the scan even if
+                 * they are on the current channel now.
+                 */
+        } else if (aphy->chan_idx == selected->chan_idx)
                 return;
         aphy->state = ATH_WIPHY_PAUSED;
         ieee80211_stop_queues(aphy->hw);