From:   Sascha Hauer <s.hauer@pengutronix.de>
To:     linux-wireless@vger.kernel.org
Cc:     Neo Jou <neojou@gmail.com>, Hans Ulli Kroll <linux@ulli-kroll.de>,
        Ping-Ke Shih <pkshih@realtek.com>,
        Yan-Hsuan Chuang <tony0620emma@gmail.com>,
        Kalle Valo <kvalo@kernel.org>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Martin Blumenstingl <martin.blumenstingl@googlemail.com>,
        kernel@pengutronix.de, Alexander Hochbaum <alex@appudo.com>,
        Da Xue <da@libre.computer>, Po-Hao Huang <phhuang@realtek.com>,
        Andreas Henriksson <andreas@fatal.se>,
        Viktor Petrenko <g0000ga@gmail.com>,
        Sascha Hauer <s.hauer@pengutronix.de>
Subject: [PATCH v2 2/3] wifi: rtw88: usb: send Zero length packets if necessary
Date:   Fri, 10 Feb 2023 12:16:31 +0100
Message-Id: <20230210111632.1985205-3-s.hauer@pengutronix.de>
In-Reply-To: <20230210111632.1985205-1-s.hauer@pengutronix.de>
References: <20230210111632.1985205-1-s.hauer@pengutronix.de>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Zero length packets are necessary when sending URBs with size
multiple of bulkout_size, otherwise the hardware just stalls.

Fixes: a82dfd33d1237 ("wifi: rtw88: Add common USB chip support")
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 drivers/net/wireless/realtek/rtw88/usb.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/wireless/realtek/rtw88/usb.c b/drivers/net/wireless/realtek/rtw88/usb.c
index d9e995544e405..1a09c9288198a 100644
--- a/drivers/net/wireless/realtek/rtw88/usb.c
+++ b/drivers/net/wireless/realtek/rtw88/usb.c
@@ -271,6 +271,7 @@ static int rtw_usb_write_port(struct rtw_dev *rtwdev, u8 qsel, struct sk_buff *s
 		return -ENOMEM;
 
 	usb_fill_bulk_urb(urb, usbd, pipe, skb->data, skb->len, cb, context);
+	urb->transfer_flags |= URB_ZERO_PACKET;
 	ret = usb_submit_urb(urb, GFP_ATOMIC);
 
 	usb_free_urb(urb);
-- 
2.30.2