wl12xx: rearrange some ELP wake_up/sleep calls

ELP (Extremely/Enhanced Low Power, or something like that ;)) refers to
the powerstate of the 12xx chip, in which very low power is consumed,
and no commands (from the host) can be issued until the chip is woken up.

Wakeup/sleep commands must be protected by a wl->mutex, so it's generally
a good idea to call wakeup/sleep along with the mutex lock/unlock (where
needed). However, in some places the wl12xx driver calls wakeup/sleep in
some "inner" functions. This result in some "nested" wakeup/sleep calls
which might end up letting the chip go to sleep prematurely (e.g. during
event handling).

Fix it by rearranging the elp calls to come along with mutex_lock/unlock.
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Ido Yariv <ido@wizery.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>

drivers/net/wireless/wl12xx/event.c

@@ -33,6 +33,7 @@ void wl1271_pspoll_work(struct work_struct *work)
 {
 	struct delayed_work *dwork;
 	struct wl1271 *wl;
+	int ret;
 
 	dwork = container_of(work, struct delayed_work, work);
 	wl = container_of(dwork, struct wl1271, pspoll_work);
@@ -55,8 +56,13 @@ void wl1271_pspoll_work(struct work_struct *work)
 	 * delivery failure occurred, and no-one changed state since, so
 	 * we should go back to powersave.
 	 */
+	ret = wl1271_ps_elp_wakeup(wl);
+	if (ret < 0)
+		goto out;
+
 	wl1271_ps_set_mode(wl, STATION_POWER_SAVE_MODE, wl->basic_rate, true);
 
+	wl1271_ps_elp_sleep(wl);
 out:
 	mutex_unlock(&wl->mutex);
 };
@@ -129,11 +135,6 @@ static int wl1271_event_ps_report(struct wl1271 *wl,
 
 		/* enable beacon early termination */
 		ret = wl1271_acx_bet_enable(wl, true);
-		if (ret < 0)
-			break;
-
-		/* go to extremely low power mode */
-		wl1271_ps_elp_sleep(wl);
 		break;
 	default:
 		break;

drivers/net/wireless/wl12xx/main.c

@@ -2792,7 +2792,9 @@ static int wl1271_op_conf_tx(struct ieee80211_hw *hw, u16 queue,
 		conf_tid->ack_policy = CONF_ACK_POLICY_LEGACY;
 		conf_tid->apsd_conf[0] = 0;
 		conf_tid->apsd_conf[1] = 0;
-	} else {
+		goto out;
+	}
+
 	ret = wl1271_ps_elp_wakeup(wl);
 	if (ret < 0)
 		goto out;
@@ -2812,12 +2814,9 @@ static int wl1271_op_conf_tx(struct ieee80211_hw *hw, u16 queue,
 				 wl1271_tx_get_queue(queue),
 				 ps_scheme, CONF_ACK_POLICY_LEGACY,
 				 0, 0);
-		if (ret < 0)
-			goto out_sleep;
 
 out_sleep:
 	wl1271_ps_elp_sleep(wl);
-	}
 
 out:
 	mutex_unlock(&wl->mutex);

drivers/net/wireless/wl12xx/ps.c

@@ -149,9 +149,6 @@ int wl1271_ps_set_mode(struct wl1271 *wl, enum wl1271_cmd_ps_mode mode,
 	case STATION_ACTIVE_MODE:
 	default:
 		wl1271_debug(DEBUG_PSM, "leaving psm");
-		ret = wl1271_ps_elp_wakeup(wl);
-		if (ret < 0)
-			return ret;
 
 		/* disable beacon early termination */
 		ret = wl1271_acx_bet_enable(wl, false);

drivers/net/wireless/wl12xx/tx.c

@@ -511,22 +511,14 @@ static void wl1271_skb_queue_head(struct wl1271 *wl, struct sk_buff *skb)
 void wl1271_tx_work_locked(struct wl1271 *wl)
 {
 	struct sk_buff *skb;
-	bool woken_up = false;
 	u32 buf_offset = 0;
 	bool sent_packets = false;
 	int ret;
 
 	if (unlikely(wl->state == WL1271_STATE_OFF))
-		goto out;
+		return;
 
 	while ((skb = wl1271_skb_dequeue(wl))) {
-		if (!woken_up) {
-			ret = wl1271_ps_elp_wakeup(wl);
-			if (ret < 0)
-				goto out_ack;
-			woken_up = true;
-		}
-
 		ret = wl1271_prepare_tx_frame(wl, skb, buf_offset);
 		if (ret == -EAGAIN) {
 			/*
@@ -573,18 +565,22 @@ void wl1271_tx_work_locked(struct wl1271 *wl)
 
 		wl1271_handle_tx_low_watermark(wl);
 	}
-
-out:
-	if (woken_up)
-		wl1271_ps_elp_sleep(wl);
 }
 
 void wl1271_tx_work(struct work_struct *work)
 {
 	struct wl1271 *wl = container_of(work, struct wl1271, tx_work);
+	int ret;
 
 	mutex_lock(&wl->mutex);
+	ret = wl1271_ps_elp_wakeup(wl);
+	if (ret < 0)
+		goto out;
+
 	wl1271_tx_work_locked(wl);
+
+	wl1271_ps_elp_wakeup(wl);
+out:
 	mutex_unlock(&wl->mutex);
 }