[PATCH] usb: gadget: u_ether: Continue to send skbs if remote wakeup fails

[zhilin.yang]

While UDC suspends, u_ether attempts to remote wakeup
the host if there are any pending transfers. If there are no
pending transfers, the is_suspend flag is set. If the is_suspend
flag is set, it attempts to remote wakeup the host when start to
send skbs. However, if host does not support remote wakeup, skbs
will never be sent.

To fix this, stop to queue skbs and return NETDEV_TX_BUSY only if
remote wakeup operation is successful.

Signed-off-by: zhilin.yang <zlyang_001@xxxxxxx>
---
 drivers/usb/gadget/function/u_ether.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/gadget/function/u_ether.c b/drivers/usb/gadget/function/u_ether.c
index f58590bf5..9d746ed3f 100644
--- a/drivers/usb/gadget/function/u_ether.c
+++ b/drivers/usb/gadget/function/u_ether.c
@@ -473,10 +473,11 @@ static netdev_tx_t eth_start_xmit(struct sk_buff *skb,
 
 	if (dev->port_usb && dev->port_usb->is_suspend) {
 		DBG(dev, "Port suspended. Triggering wakeup\n");
-		netif_stop_queue(net);
-		spin_unlock_irqrestore(&dev->lock, flags);
-		ether_wakeup_host(dev->port_usb);
-		return NETDEV_TX_BUSY;
+		if (!ether_wakeup_host(dev->port_usb)) {
+			netif_stop_queue(net);
+			spin_unlock_irqrestore(&dev->lock, flags);
+			return NETDEV_TX_BUSY;
+		}
 	}
 
 	spin_unlock_irqrestore(&dev->lock, flags);
-- 
2.25.1