Received-SPF: pass (google.com: domain of linux-kernel+bounces-148193-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:4601:e00::3 as permitted sender) client-ip=2604:1380:4601:e00::3;
From: Jose Ignacio Tornos Martinez <jtornosm@redhat.com>
To: davem@davemloft.net,
	edumazet@google.com,
	kuba@kernel.org,
	pabeni@redhat.com,
	linux-usb@vger.kernel.org,
	netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org
Cc: Jose Ignacio Tornos Martinez <jtornosm@redhat.com>,
	stable@vger.kernel.org,
	Jarkko Palviainen <jarkko.palviainen@gmail.com>
Subject: [PATCH v2] net: usb: ax88179_178a: avoid writing the mac address before first reading
Date: Wed, 17 Apr 2024 10:55:13 +0200
Message-ID: <20240417085524.219532-1-jtornosm@redhat.com>
Precedence: bulk
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit

After the commit d2689b6a86b9 ("net: usb: ax88179_178a: avoid two
consecutive device resets"), reset operation, in which the default mac
address from the device is read, is not executed from bind operation and
the random address, that is pregenerated just in case, is direclty written
the first time in the device, so the default one from the device is not
even read. This writing is not dangerous because is volatile and the
default mac address is not missed.

In order to avoid this and keep the simplification to have only one
reset and reduce the delays, restore the reset from bind operation and
remove the reset that is commanded from open operation. The behavior is
the same but everything is ready for usbnet_probe.

Tested with ASIX AX88179 USB Gigabit Ethernet devices.
Restore the old behavior for the rest of possible devices because I don't
have the hardware to test.

cc: stable@vger.kernel.org # 6.6+
Fixes: d2689b6a86b9 ("net: usb: ax88179_178a: avoid two consecutive device resets")
Reported-by: Jarkko Palviainen <jarkko.palviainen@gmail.com>
Signed-off-by: Jose Ignacio Tornos Martinez <jtornosm@redhat.com>
---
v2:
  - Restore reset from bind operation to avoid problems with usbnet_probe.
v1: https://lore.kernel.org/netdev/20240410095603.502566-1-jtornosm@redhat.com/

 drivers/net/usb/ax88179_178a.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/usb/ax88179_178a.c b/drivers/net/usb/ax88179_178a.c
index 69169842fa2f..a493fde1af3f 100644
--- a/drivers/net/usb/ax88179_178a.c
+++ b/drivers/net/usb/ax88179_178a.c
@@ -1316,6 +1316,8 @@ static int ax88179_bind(struct usbnet *dev, struct usb_interface *intf)
 
 	netif_set_tso_max_size(dev->net, 16384);
 
+	ax88179_reset(dev);
+
 	return 0;
 }
 
@@ -1694,7 +1696,6 @@ static const struct driver_info ax88179_info = {
 	.unbind = ax88179_unbind,
 	.status = ax88179_status,
 	.link_reset = ax88179_link_reset,
-	.reset = ax88179_reset,
 	.stop = ax88179_stop,
 	.flags = FLAG_ETHER | FLAG_FRAMING_AX,
 	.rx_fixup = ax88179_rx_fixup,
@@ -1707,7 +1708,6 @@ static const struct driver_info ax88178a_info = {
 	.unbind = ax88179_unbind,
 	.status = ax88179_status,
 	.link_reset = ax88179_link_reset,
-	.reset = ax88179_reset,
 	.stop = ax88179_stop,
 	.flags = FLAG_ETHER | FLAG_FRAMING_AX,
 	.rx_fixup = ax88179_rx_fixup,
-- 
2.44.0