wl1271: Flush TX buffers to air before going to idle

The mac80211 changes to idle almost immediately after transmitting some
frames, such as deauth etc. When going to idle, the wl1271 is disconnected,
which causes TX frames already on buffers, but not yet transmitted, to be
deleted.

To make sure deauth frames reach the air, allow the TX buffers to flush
before proceeding to idle.

Signed-off-by: Juuso Oikarinen <juuso.oikarinen@nokia.com>
Reviewed-by: Teemu Paasikivi <ext-teemu.3.paasikivi@nokia.com>
Signed-off-by: Luciano Coelho <luciano.coelho@nokia.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 33 insertions, 3 deletions

diff --git a/drivers/net/wireless/wl12xx/wl1271_tx.c b/drivers/net/wireless/wl12xx/wl1271_tx.c
index 62db79508ddf..c592cc2e9fe8 100644
--- a/drivers/net/wireless/wl12xx/wl1271_tx.c
+++ b/drivers/net/wireless/wl12xx/wl1271_tx.c
@@ -36,6 +36,7 @@ static int wl1271_tx_id(struct wl1271 *wl, struct sk_buff *skb)
         for (i = 0; i < ACX_TX_DESCRIPTORS; i++)
                 if (wl->tx_frames[i] == NULL) {
                         wl->tx_frames[i] = skb;
+                        wl->tx_frames_cnt++;
                         return i;
                 }
 
@@ -73,8 +74,10 @@ static int wl1271_tx_allocate(struct wl1271 *wl, struct sk_buff *skb, u32 extra)
                 wl1271_debug(DEBUG_TX,
                              "tx_allocate: size: %d, blocks: %d, id: %d",
                              total_len, total_blocks, id);
-        } else
+        } else {
                 wl->tx_frames[id] = NULL;
+                wl->tx_frames_cnt--;
+        }
 
         return ret;
 }
@@ -358,6 +361,7 @@ static void wl1271_tx_complete_packet(struct wl1271 *wl,
         /* return the packet to the stack */
         ieee80211_tx_status(wl->hw, skb);
         wl->tx_frames[result->id] = NULL;
+        wl->tx_frames_cnt--;
 }
 
 /* Called upon reception of a TX complete interrupt */
@@ -412,7 +416,7 @@ void wl1271_tx_complete(struct wl1271 *wl)
 }
 
 /* caller must hold wl->mutex */
-void wl1271_tx_flush(struct wl1271 *wl)
+void wl1271_tx_reset(struct wl1271 *wl)
 {
         int i;
         struct sk_buff *skb;
@@ -421,7 +425,7 @@ void wl1271_tx_flush(struct wl1271 *wl)
 /*      control->flags = 0; FIXME */
 
         while ((skb = skb_dequeue(&wl->tx_queue))) {
-                wl1271_debug(DEBUG_TX, "flushing skb 0x%p", skb);
+                wl1271_debug(DEBUG_TX, "freeing skb 0x%p", skb);
                 ieee80211_tx_status(wl->hw, skb);
         }
 
@@ -429,6 +433,32 @@ void wl1271_tx_flush(struct wl1271 *wl)
                 if (wl->tx_frames[i] != NULL) {
                         skb = wl->tx_frames[i];
                         wl->tx_frames[i] = NULL;
+                        wl1271_debug(DEBUG_TX, "freeing skb 0x%p", skb);
                         ieee80211_tx_status(wl->hw, skb);
                 }
+        wl->tx_frames_cnt = 0;
+}
+
+#define WL1271_TX_FLUSH_TIMEOUT 500000
+
+/* caller must *NOT* hold wl->mutex */
+void wl1271_tx_flush(struct wl1271 *wl)
+{
+        unsigned long timeout;
+        timeout = jiffies + usecs_to_jiffies(WL1271_TX_FLUSH_TIMEOUT);
+
+        while (!time_after(jiffies, timeout)) {
+                mutex_lock(&wl->mutex);
+                wl1271_debug(DEBUG_TX, "flushing tx buffer: %d",
+                             wl->tx_frames_cnt);
+                if ((wl->tx_frames_cnt == 0) &&
+                    skb_queue_empty(&wl->tx_queue)) {
+                        mutex_unlock(&wl->mutex);
+                        return;
+                }
+                mutex_unlock(&wl->mutex);
+                msleep(1);
+        }
+
+        wl1271_warning("Unable to flush all TX buffers, timed out.");
 }