[PATCH 2/4] wlcore: Use spin_trylock in wlcore_irq() to see if we need to queue tx

[Tony Lindgren <tony@atomide.com>]

We need the spinlock to check if we need to queue tx in wlcore_irq().
Let's use spin_trylock instead and always queue tx unless we know there's
nothing to do.

Let's also update the comment a bit while at it.

Signed-off-by: Tony Lindgren <tony@atomide.com>
---
 drivers/net/wireless/ti/wlcore/main.c | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/drivers/net/wireless/ti/wlcore/main.c b/drivers/net/wireless/ti/wlcore/main.c
--- a/drivers/net/wireless/ti/wlcore/main.c
+++ b/drivers/net/wireless/ti/wlcore/main.c
@@ -652,6 +652,7 @@ static irqreturn_t wlcore_irq(int irq, void *cookie)
 	int ret;
 	unsigned long flags;
 	struct wl1271 *wl = cookie;
+	bool queue_tx_work = true;
 
 	/* complete the ELP completion */
 	spin_lock_irqsave(&wl->wl_lock, flags);
@@ -682,13 +683,17 @@ static irqreturn_t wlcore_irq(int irq, void *cookie)
 	if (ret)
 		wl12xx_queue_recovery_work(wl);
 
-	spin_lock_irqsave(&wl->wl_lock, flags);
-	/* In case TX was not handled here, queue TX work */
+	/* In case TX was not handled in wlcore_irq_locked(), queue TX work */
 	clear_bit(WL1271_FLAG_TX_PENDING, &wl->flags);
-	if (!test_bit(WL1271_FLAG_FW_TX_BUSY, &wl->flags) &&
-	    wl1271_tx_total_queue_count(wl) > 0)
-		ieee80211_queue_work(wl->hw, &wl->tx_work);
-	spin_unlock_irqrestore(&wl->wl_lock, flags);
+	if (!test_bit(WL1271_FLAG_FW_TX_BUSY, &wl->flags)) {
+		if (spin_trylock_irqsave(&wl->wl_lock, flags)) {
+			if (!wl1271_tx_total_queue_count(wl))
+				queue_tx_work = false;
+			spin_unlock_irqrestore(&wl->wl_lock, flags);
+		}
+		if (queue_tx_work)
+			ieee80211_queue_work(wl->hw, &wl->tx_work);
+	}
 
 	mutex_unlock(&wl->mutex);
 
-- 
2.27.0