[PATCH v3] net: usb: ax88179_178a: Bind only to vendor-specific interface

[PATCH v3] net: usb: ax88179_178a: Bind only to vendor-specific interface

[Hector Martin]

The Anker PowerExpand USB-C to Gigabit Ethernet adapter uses this
chipset, but exposes CDC Ethernet configurations as well as the
vendor specific one. This driver ends up binding first to both CDC
interfaces, tries to instantiate two Ethernet interfaces talking to
the same device, and the result is a nice fireworks show.

Change all the ID matches to specifically match the vendor-specific
interface. By default the device comes up in CDC mode and is bound by
that driver (which works fine); users may switch it to the vendor
interface using sysfs to set bConfigurationValue, at which point the
device actually goes through a reconnect cycle and comes back as a
vendor specific only device, and then this driver binds and works too.

The affected device uses VID/PID 0b95:1790, but we might as well change
all of them for good measure, since there is no good reason for this
driver to bind to standard CDC Ethernet interfaces.

v3: Added VID/PID info to commit message

Signed-off-by: Hector Martin <marcan@marcan.st>
---
 drivers/net/usb/ax88179_178a.c | 26 +++++++++++++-------------
 1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/drivers/net/usb/ax88179_178a.c b/drivers/net/usb/ax88179_178a.c
index e2fa56b92685..7c7c2f31d9f1 100644
--- a/drivers/net/usb/ax88179_178a.c
+++ b/drivers/net/usb/ax88179_178a.c
@@ -1914,55 +1914,55 @@ static const struct driver_info at_umc2000sp_info = {
 static const struct usb_device_id products[] = {
 {
 	/* ASIX AX88179 10/100/1000 */
-	USB_DEVICE(0x0b95, 0x1790),
+	USB_DEVICE_AND_INTERFACE_INFO(0x0b95, 0x1790, 0xff, 0xff, 0),
 	.driver_info = (unsigned long)&ax88179_info,
 }, {
 	/* ASIX AX88178A 10/100/1000 */
-	USB_DEVICE(0x0b95, 0x178a),
+	USB_DEVICE_AND_INTERFACE_INFO(0x0b95, 0x178a, 0xff, 0xff, 0),
 	.driver_info = (unsigned long)&ax88178a_info,
 }, {
 	/* Cypress GX3 SuperSpeed to Gigabit Ethernet Bridge Controller */
-	USB_DEVICE(0x04b4, 0x3610),
+	USB_DEVICE_AND_INTERFACE_INFO(0x04b4, 0x3610, 0xff, 0xff, 0),
 	.driver_info = (unsigned long)&cypress_GX3_info,
 }, {
 	/* D-Link DUB-1312 USB 3.0 to Gigabit Ethernet Adapter */
-	USB_DEVICE(0x2001, 0x4a00),
+	USB_DEVICE_AND_INTERFACE_INFO(0x2001, 0x4a00, 0xff, 0xff, 0),
 	.driver_info = (unsigned long)&dlink_dub1312_info,
 }, {
 	/* Sitecom USB 3.0 to Gigabit Adapter */
-	USB_DEVICE(0x0df6, 0x0072),
+	USB_DEVICE_AND_INTERFACE_INFO(0x0df6, 0x0072, 0xff, 0xff, 0),
 	.driver_info = (unsigned long)&sitecom_info,
 }, {
 	/* Samsung USB Ethernet Adapter */
-	USB_DEVICE(0x04e8, 0xa100),
+	USB_DEVICE_AND_INTERFACE_INFO(0x04e8, 0xa100, 0xff, 0xff, 0),
 	.driver_info = (unsigned long)&samsung_info,
 }, {
 	/* Lenovo OneLinkDock Gigabit LAN */
-	USB_DEVICE(0x17ef, 0x304b),
+	USB_DEVICE_AND_INTERFACE_INFO(0x17ef, 0x304b, 0xff, 0xff, 0),
 	.driver_info = (unsigned long)&lenovo_info,
 }, {
 	/* Belkin B2B128 USB 3.0 Hub + Gigabit Ethernet Adapter */
-	USB_DEVICE(0x050d, 0x0128),
+	USB_DEVICE_AND_INTERFACE_INFO(0x050d, 0x0128, 0xff, 0xff, 0),
 	.driver_info = (unsigned long)&belkin_info,
 }, {
 	/* Toshiba USB 3.0 GBit Ethernet Adapter */
-	USB_DEVICE(0x0930, 0x0a13),
+	USB_DEVICE_AND_INTERFACE_INFO(0x0930, 0x0a13, 0xff, 0xff, 0),
 	.driver_info = (unsigned long)&toshiba_info,
 }, {
 	/* Magic Control Technology U3-A9003 USB 3.0 Gigabit Ethernet Adapter */
-	USB_DEVICE(0x0711, 0x0179),
+	USB_DEVICE_AND_INTERFACE_INFO(0x0711, 0x0179, 0xff, 0xff, 0),
 	.driver_info = (unsigned long)&mct_info,
 }, {
 	/* Allied Telesis AT-UMC2000 USB 3.0/USB 3.1 Gen 1 to Gigabit Ethernet Adapter */
-	USB_DEVICE(0x07c9, 0x000e),
+	USB_DEVICE_AND_INTERFACE_INFO(0x07c9, 0x000e, 0xff, 0xff, 0),
 	.driver_info = (unsigned long)&at_umc2000_info,
 }, {
 	/* Allied Telesis AT-UMC200 USB 3.0/USB 3.1 Gen 1 to Fast Ethernet Adapter */
-	USB_DEVICE(0x07c9, 0x000f),
+	USB_DEVICE_AND_INTERFACE_INFO(0x07c9, 0x000f, 0xff, 0xff, 0),
 	.driver_info = (unsigned long)&at_umc200_info,
 }, {
 	/* Allied Telesis AT-UMC2000/SP USB 3.0/USB 3.1 Gen 1 to Gigabit Ethernet Adapter */
-	USB_DEVICE(0x07c9, 0x0010),
+	USB_DEVICE_AND_INTERFACE_INFO(0x07c9, 0x0010, 0xff, 0xff, 0),
 	.driver_info = (unsigned long)&at_umc2000sp_info,
 },
 	{ },
-- 
2.35.1

Re: [PATCH v3] net: usb: ax88179_178a: Bind only to vendor-specific interface

[Oliver Neukum]

On 21.06.22 12:21, Hector Martin wrote:
> The Anker PowerExpand USB-C to Gigabit Ethernet adapter uses this
> chipset, but exposes CDC Ethernet configurations as well as the
> vendor specific one. This driver ends up binding first to both CDC
> interfaces, tries to instantiate two Ethernet interfaces talking to
> the same device, and the result is a nice fireworks show.

Could you explicitly state here that the root cause is that the
driver for the vendor specific mode binds to the device based only
on vendor:product ID, thus taking interfaces that only the
class driver can handle properly?

This log reads like the basic issue is that it binds to two
interfaces.

The patch itself is fine.

	Regards
		Oliver