[PATCH 2/3] mt76: sdio: poll sta stat when device transmits data

[sean.wang at mediatek.com]

From: Sean Wang <sean.wang at mediatek.com>

It is not meaningful to poll sta stat when there is no the data traffic.
So polling sta stat when device have transmitted data instead to save
CPU power.

That implies that it is unallowed the stat_work to work while MCU is
being initialized in the really early stage. That is a required patch
for ("mt76: mt7663s: fix the deadlock caused by sdio->stat_work")
because mt7615_mcu_set_drv_ctrl pointer isn't set done until MCU is
ready.

Fixes: d39b52e31aa6 ("mt76: introduce mt76_sdio module")
Signed-off-by: Sean Wang <sean.wang at mediatek.com>
---
 drivers/net/wireless/mediatek/mt76/sdio.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/mediatek/mt76/sdio.c b/drivers/net/wireless/mediatek/mt76/sdio.c
index aba2a9865821..3b9bb7cd08ad 100644
--- a/drivers/net/wireless/mediatek/mt76/sdio.c
+++ b/drivers/net/wireless/mediatek/mt76/sdio.c
@@ -478,7 +478,7 @@ static void mt76s_status_worker(struct mt76_worker *w)
 		if (ndata_frames > 0)
 			resched = true;
 
-		if (dev->drv->tx_status_data &&
+		if (dev->drv->tx_status_data && ndata_frames > 0 &&
 		    !test_and_set_bit(MT76_READING_STATS, &dev->phy.state) &&
 		    !test_bit(MT76_STATE_SUSPEND, &dev->phy.state))
 			queue_work(dev->wq, &dev->sdio.stat_work);
-- 
2.25.1