[PATCHv3 net-next 1/9] net: usb: move updating filter and status from cdc drivers to usbnet

[PATCHv3 net-next 1/9] net: usb: move updating filter and status from cdc drivers to usbnet

[Oliver Neukum]

These helpers are used by multiple drivers and do not depend
on the rest. For example rndis_host will also need cdc_ether.
Leaving them in a cdc driver means that additional drivers are loaded
just as a library, not to support hardware by themselves.

Signed-off-by: Oliver Neukum <oneukum@suse.com>
---

v2:
- update change log entry

 drivers/net/usb/cdc_ether.c | 75 -----------------------------------
 drivers/net/usb/usbnet.c    | 79 +++++++++++++++++++++++++++++++++++++
 2 files changed, 79 insertions(+), 75 deletions(-)

diff --git a/drivers/net/usb/cdc_ether.c b/drivers/net/usb/cdc_ether.c
index a0a5740590b9..b4df32e18461 100644
--- a/drivers/net/usb/cdc_ether.c
+++ b/drivers/net/usb/cdc_ether.c
@@ -63,35 +63,6 @@ static const u8 mbm_guid[16] = {
 	0xa6, 0x07, 0xc0, 0xff, 0xcb, 0x7e, 0x39, 0x2a,
 };
 
-void usbnet_cdc_update_filter(struct usbnet *dev)
-{
-	struct net_device	*net = dev->net;
-
-	u16 cdc_filter = USB_CDC_PACKET_TYPE_DIRECTED
-			| USB_CDC_PACKET_TYPE_BROADCAST;
-
-	/* filtering on the device is an optional feature and not worth
-	 * the hassle so we just roughly care about snooping and if any
-	 * multicast is requested, we take every multicast
-	 */
-	if (net->flags & IFF_PROMISC)
-		cdc_filter |= USB_CDC_PACKET_TYPE_PROMISCUOUS;
-	if (!netdev_mc_empty(net) || (net->flags & IFF_ALLMULTI))
-		cdc_filter |= USB_CDC_PACKET_TYPE_ALL_MULTICAST;
-
-	usb_control_msg(dev->udev,
-			usb_sndctrlpipe(dev->udev, 0),
-			USB_CDC_SET_ETHERNET_PACKET_FILTER,
-			USB_TYPE_CLASS | USB_RECIP_INTERFACE,
-			cdc_filter,
-			dev->intf->cur_altsetting->desc.bInterfaceNumber,
-			NULL,
-			0,
-			USB_CTRL_SET_TIMEOUT
-		);
-}
-EXPORT_SYMBOL_GPL(usbnet_cdc_update_filter);
-
 /* We need to override usbnet_*_link_ksettings in bind() */
 static const struct ethtool_ops cdc_ether_ethtool_ops = {
 	.get_link		= usbnet_get_link,
@@ -400,52 +371,6 @@ EXPORT_SYMBOL_GPL(usbnet_cdc_unbind);
  * (by Brad Hards) talked with, with more functionality.
  */
 
-static void speed_change(struct usbnet *dev, __le32 *speeds)
-{
-	dev->tx_speed = __le32_to_cpu(speeds[0]);
-	dev->rx_speed = __le32_to_cpu(speeds[1]);
-}
-
-void usbnet_cdc_status(struct usbnet *dev, struct urb *urb)
-{
-	struct usb_cdc_notification	*event;
-
-	if (urb->actual_length < sizeof(*event))
-		return;
-
-	/* SPEED_CHANGE can get split into two 8-byte packets */
-	if (test_and_clear_bit(EVENT_STS_SPLIT, &dev->flags)) {
-		speed_change(dev, (__le32 *) urb->transfer_buffer);
-		return;
-	}
-
-	event = urb->transfer_buffer;
-	switch (event->bNotificationType) {
-	case USB_CDC_NOTIFY_NETWORK_CONNECTION:
-		netif_dbg(dev, timer, dev->net, "CDC: carrier %s\n",
-			  event->wValue ? "on" : "off");
-		if (netif_carrier_ok(dev->net) != !!event->wValue)
-			usbnet_link_change(dev, !!event->wValue, 0);
-		break;
-	case USB_CDC_NOTIFY_SPEED_CHANGE:	/* tx/rx rates */
-		netif_dbg(dev, timer, dev->net, "CDC: speed change (len %d)\n",
-			  urb->actual_length);
-		if (urb->actual_length != (sizeof(*event) + 8))
-			set_bit(EVENT_STS_SPLIT, &dev->flags);
-		else
-			speed_change(dev, (__le32 *) &event[1]);
-		break;
-	/* USB_CDC_NOTIFY_RESPONSE_AVAILABLE can happen too (e.g. RNDIS),
-	 * but there are no standard formats for the response data.
-	 */
-	default:
-		netdev_err(dev->net, "CDC: unexpected notification %02x!\n",
-			   event->bNotificationType);
-		break;
-	}
-}
-EXPORT_SYMBOL_GPL(usbnet_cdc_status);
-
 int usbnet_cdc_bind(struct usbnet *dev, struct usb_interface *intf)
 {
 	int				status;
diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index 25518635b7b7..21c55d70f27c 100644
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -22,6 +22,7 @@
 #include <linux/init.h>
 #include <linux/netdevice.h>
 #include <linux/etherdevice.h>
+#include <linux/usb/cdc.h>
 #include <linux/ctype.h>
 #include <linux/ethtool.h>
 #include <linux/workqueue.h>
@@ -2271,6 +2272,84 @@ int usbnet_write_cmd_async(struct usbnet *dev, u8 cmd, u8 reqtype,
 
 }
 EXPORT_SYMBOL_GPL(usbnet_write_cmd_async);
+
+void usbnet_cdc_update_filter(struct usbnet *dev)
+{
+	struct net_device	*net = dev->net;
+
+	u16 cdc_filter = USB_CDC_PACKET_TYPE_DIRECTED
+			| USB_CDC_PACKET_TYPE_BROADCAST;
+
+	/* filtering on the device is an optional feature and not worth
+	 * the hassle so we just roughly care about snooping and if any
+	 * multicast is requested, we take every multicast
+	 */
+	if (net->flags & IFF_PROMISC)
+		cdc_filter |= USB_CDC_PACKET_TYPE_PROMISCUOUS;
+	if (!netdev_mc_empty(net) || (net->flags & IFF_ALLMULTI))
+		cdc_filter |= USB_CDC_PACKET_TYPE_ALL_MULTICAST;
+
+	usb_control_msg(dev->udev,
+			usb_sndctrlpipe(dev->udev, 0),
+			USB_CDC_SET_ETHERNET_PACKET_FILTER,
+			USB_TYPE_CLASS | USB_RECIP_INTERFACE,
+			cdc_filter,
+			dev->intf->cur_altsetting->desc.bInterfaceNumber,
+			NULL,
+			0,
+			USB_CTRL_SET_TIMEOUT
+		);
+}
+EXPORT_SYMBOL_GPL(usbnet_cdc_update_filter);
+
+static void speed_change(struct usbnet *dev, __le32 *speeds)
+{
+	dev->tx_speed = __le32_to_cpu(speeds[0]);
+	dev->rx_speed = __le32_to_cpu(speeds[1]);
+}
+
+void usbnet_cdc_status(struct usbnet *dev, struct urb *urb)
+{
+	struct usb_cdc_notification	*event;
+
+	if (urb->actual_length < sizeof(*event)) {
+		/* we cannot assume the device is in sync with us*/ 
+		clear_bit(EVENT_STS_SPLIT, &dev->flags);
+		return;
+	}
+
+	/* SPEED_CHANGE can get split into two 8-byte packets */
+	if (test_and_clear_bit(EVENT_STS_SPLIT, &dev->flags)) {
+		speed_change(dev, (__le32 *)urb->transfer_buffer);
+		return;
+	}
+
+	event = urb->transfer_buffer;
+	switch (event->bNotificationType) {
+	case USB_CDC_NOTIFY_NETWORK_CONNECTION:
+		netif_dbg(dev, timer, dev->net, "CDC: carrier %s\n",
+			  event->wValue ? "on" : "off");
+		if (netif_carrier_ok(dev->net) != !!event->wValue)
+			usbnet_link_change(dev, !!event->wValue, 0);
+		break;
+	case USB_CDC_NOTIFY_SPEED_CHANGE:	/* tx/rx rates */
+		netif_dbg(dev, timer, dev->net, "CDC: speed change (len %d)\n",
+			  urb->actual_length);
+		if (urb->actual_length != (sizeof(*event) + 8))
+			set_bit(EVENT_STS_SPLIT, &dev->flags);
+		else
+			speed_change(dev, (__le32 *)&event[1]);
+		break;
+	/* USB_CDC_NOTIFY_RESPONSE_AVAILABLE can happen too (e.g. RNDIS),
+	 * but there are no standard formats for the response data.
+	 */
+	default:
+		netdev_err(dev->net, "CDC: unexpected notification %02x!\n",
+			   event->bNotificationType);
+		break;
+	}
+}
+EXPORT_SYMBOL_GPL(usbnet_cdc_status);
 /*-------------------------------------------------------------------------*/
 
 static int __init usbnet_init(void)
-- 
2.54.0

[PATCHv3 net-next 2/9] net: usb: centralize usbnet_cdc_zte_rx_fixup in usbnet

[Oliver Neukum]

This helper is used by multiple drivers using usbnet.
It is better to be provided by usbnet than one of them.

Signed-off-by: Oliver Neukum <oneukum@suse.com>
---

v2:
- spelling issues
- issue with lost synchronization with SPLIT packets

 drivers/net/usb/cdc_ether.c | 19 -------------------
 drivers/net/usb/usbnet.c    | 19 +++++++++++++++++++
 2 files changed, 19 insertions(+), 19 deletions(-)

diff --git a/drivers/net/usb/cdc_ether.c b/drivers/net/usb/cdc_ether.c
index b4df32e18461..e688fb99c61d 100644
--- a/drivers/net/usb/cdc_ether.c
+++ b/drivers/net/usb/cdc_ether.c
@@ -404,25 +404,6 @@ static int usbnet_cdc_zte_bind(struct usbnet *dev, struct usb_interface *intf)
 	return status;
 }
 
-/* Make sure packets have correct destination MAC address
- *
- * A firmware bug observed on some devices (ZTE MF823/831/910) is that the
- * device sends packets with a static, bogus, random MAC address (event if
- * device MAC address has been updated). Always set MAC address to that of the
- * device.
- */
-int usbnet_cdc_zte_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
-{
-	if (skb->len < ETH_HLEN || !(skb->data[0] & 0x02))
-		return 1;
-
-	skb_reset_mac_header(skb);
-	ether_addr_copy(eth_hdr(skb)->h_dest, dev->net->dev_addr);
-
-	return 1;
-}
-EXPORT_SYMBOL_GPL(usbnet_cdc_zte_rx_fixup);
-
 /* Ensure correct link state
  *
  * Some devices (ZTE MF823/831/910) export two carrier on notifications when
diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index 21c55d70f27c..14e9f1b1e0a2 100644
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -2350,6 +2350,25 @@ void usbnet_cdc_status(struct usbnet *dev, struct urb *urb)
 	}
 }
 EXPORT_SYMBOL_GPL(usbnet_cdc_status);
+
+/* Make sure packets have correct destination MAC address
+ *
+ * A firmware bug observed on some devices (ZTE MF823/831/910) is that the
+ * device sends packets with a static, bogus, random MAC address (event if
+ * device MAC address has been updated). Always set MAC address to that of the
+ * device.
+ */
+int usbnet_cdc_zte_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
+{
+	if (skb->len < ETH_HLEN || !(skb->data[0] & 0x02))
+		return 1;
+
+	skb_reset_mac_header(skb);
+	ether_addr_copy(eth_hdr(skb)->h_dest, dev->net->dev_addr);
+
+	return 1;
+}
+EXPORT_SYMBOL_GPL(usbnet_cdc_zte_rx_fixup);
 /*-------------------------------------------------------------------------*/
 
 static int __init usbnet_init(void)
-- 
2.54.0

[PATCHv3 net-next 3/9] net: usb: usbnet: add cdc_state to struct usbnet

[Oliver Neukum]

This allows centralisation of code using cdc_state in usbnet, reducing
code duplication. No functional change intended.

Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
 include/linux/usb/usbnet.h | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/include/linux/usb/usbnet.h b/include/linux/usb/usbnet.h
index bbf799ccf3b3..79f48eb388ee 100644
--- a/include/linux/usb/usbnet.h
+++ b/include/linux/usb/usbnet.h
@@ -16,6 +16,14 @@
 #include <linux/usb.h>
 #include <linux/spinlock.h>
 
+struct cdc_state {
+	struct usb_cdc_header_desc      *header;
+	struct usb_cdc_union_desc       *u;
+	struct usb_cdc_ether_desc       *ether;
+	struct usb_interface            *control;
+	struct usb_interface            *data;
+};
+
 /* interface from usbnet core to each USB networking link we handle */
 struct usbnet {
 	/* housekeeping */
@@ -41,6 +49,7 @@ struct usbnet {
 	/* protocol/interface state */
 	struct net_device	*net;
 	int			msg_enable;
+	struct cdc_state	cdc;		/* too common to leave out*/
 	unsigned long		data[5];
 	u32			xid;
 	u32			hard_mtu;	/* count any extra framing */
@@ -211,13 +220,6 @@ extern int usbnet_write_cmd_async(struct usbnet *dev, u8 cmd, u8 reqtype,
  * (notably, using multiple interfaces according to the CDC
  * union descriptor) get some helper code.
  */
-struct cdc_state {
-	struct usb_cdc_header_desc	*header;
-	struct usb_cdc_union_desc	*u;
-	struct usb_cdc_ether_desc	*ether;
-	struct usb_interface		*control;
-	struct usb_interface		*data;
-};
 
 extern void usbnet_cdc_update_filter(struct usbnet *dev);
 extern int usbnet_generic_cdc_bind(struct usbnet *, struct usb_interface *);
-- 
2.54.0

Re: [PATCHv3 net-next 3/9] net: usb: usbnet: add cdc_state to struct usbnet

[Andrew Lunn]

On Tue, Jul 14, 2026 at 01:44:23PM +0200, Oliver Neukum wrote:
> This allows centralisation of code using cdc_state in usbnet, reducing
> code duplication. No functional change intended.
> 
> Signed-off-by: Oliver Neukum <oneukum@suse.com>

I gave a Reviewed-by to v2 of this patch. You are supposed to attach
them here on the next version. b4 collect them and add them for you,
if you use it.

   Andrew

Re: [PATCHv3 net-next 3/9] net: usb: usbnet: add cdc_state to struct usbnet

[Jakub Kicinski]

On Wed, 15 Jul 2026 03:18:00 +0200 Andrew Lunn wrote:
> On Tue, Jul 14, 2026 at 01:44:23PM +0200, Oliver Neukum wrote:
> > This allows centralisation of code using cdc_state in usbnet, reducing
> > code duplication. No functional change intended.
> > 
> > Signed-off-by: Oliver Neukum <oneukum@suse.com>  
> 
> I gave a Reviewed-by to v2 of this patch. You are supposed to attach
> them here on the next version. b4 collect them and add them for you,
> if you use it.

Yes, please repost this with the missing tags and add a cover letter.
The basics :/

[PATCHv3 net-next 4/9] net: usb: use cdc_state in struct usbnet

[Oliver Neukum]

Remove private copies as now a central state can be used.

Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
 drivers/net/usb/cdc_ether.c  | 9 +++------
 drivers/net/usb/rndis_host.c | 6 +++---
 2 files changed, 6 insertions(+), 9 deletions(-)

diff --git a/drivers/net/usb/cdc_ether.c b/drivers/net/usb/cdc_ether.c
index e688fb99c61d..76ad4ffa950a 100644
--- a/drivers/net/usb/cdc_ether.c
+++ b/drivers/net/usb/cdc_ether.c
@@ -85,7 +85,7 @@ int usbnet_generic_cdc_bind(struct usbnet *dev, struct usb_interface *intf)
 	u8				*buf = intf->cur_altsetting->extra;
 	int				len = intf->cur_altsetting->extralen;
 	struct usb_interface_descriptor	*d;
-	struct cdc_state		*info = (void *) &dev->data;
+	struct cdc_state		*info = &dev->cdc;
 	int				status = -ENODEV;
 	int				rndis;
 	bool				android_rndis_quirk = false;
@@ -336,7 +336,7 @@ EXPORT_SYMBOL_GPL(usbnet_ether_cdc_bind);
 
 void usbnet_cdc_unbind(struct usbnet *dev, struct usb_interface *intf)
 {
-	struct cdc_state		*info = (void *) &dev->data;
+	struct cdc_state		*info = &dev->cdc;
 	struct usb_driver		*driver = driver_of(intf);
 
 	/* combined interface - nothing  to do */
@@ -374,10 +374,7 @@ EXPORT_SYMBOL_GPL(usbnet_cdc_unbind);
 int usbnet_cdc_bind(struct usbnet *dev, struct usb_interface *intf)
 {
 	int				status;
-	struct cdc_state		*info = (void *) &dev->data;
-
-	BUILD_BUG_ON((sizeof(((struct usbnet *)0)->data)
-			< sizeof(struct cdc_state)));
+	struct cdc_state		*info = &dev->cdc;
 
 	status = usbnet_ether_cdc_bind(dev, intf);
 	if (status < 0)
diff --git a/drivers/net/usb/rndis_host.c b/drivers/net/usb/rndis_host.c
index 5e39d05a2d7b..d539654687c3 100644
--- a/drivers/net/usb/rndis_host.c
+++ b/drivers/net/usb/rndis_host.c
@@ -57,7 +57,7 @@ EXPORT_SYMBOL_GPL(rndis_status);
 static void rndis_msg_indicate(struct usbnet *dev, struct rndis_indicate *msg,
 				int buflen)
 {
-	struct cdc_state *info = (void *)&dev->data;
+	struct cdc_state *info = &dev->cdc;
 	struct device *udev = &info->control->dev;
 
 	if (dev->driver_info->indication) {
@@ -90,7 +90,7 @@ static void rndis_msg_indicate(struct usbnet *dev, struct rndis_indicate *msg,
  */
 int rndis_command(struct usbnet *dev, struct rndis_msg_hdr *buf, int buflen)
 {
-	struct cdc_state	*info = (void *) &dev->data;
+	struct cdc_state	*info = &dev->cdc;
 	struct usb_cdc_notification notification;
 	int			master_ifnum;
 	int			retval;
@@ -290,7 +290,7 @@ generic_rndis_bind(struct usbnet *dev, struct usb_interface *intf, int flags)
 {
 	int			retval;
 	struct net_device	*net = dev->net;
-	struct cdc_state	*info = (void *) &dev->data;
+	struct cdc_state	*info = &dev->cdc;
 	union {
 		void			*buf;
 		struct rndis_msg_hdr	*header;
-- 
2.54.0

[PATCHv3 net-next 5/9] net: usb: int51x1: drop dependency on cdc_ether

[Oliver Neukum]

The driver depended on cdc_ether only for usbnet_cdc_update_filter().
This has been shifted to usbnet. Drop the dependency.

Signed-off-by: Oliver Neukum <oneukum@suse.com>
---

v2:
- added as missed opportunity

 drivers/net/usb/Kconfig | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/net/usb/Kconfig b/drivers/net/usb/Kconfig
index 52a5c0922c79..da0f6a138f4f 100644
--- a/drivers/net/usb/Kconfig
+++ b/drivers/net/usb/Kconfig
@@ -563,7 +563,6 @@ config USB_HSO
 config USB_NET_INT51X1
 	tristate "Intellon PLC based usb adapter"
 	depends on USB_USBNET
-	select USB_NET_CDCETHER
 	help
 	  Choose this option if you're using a 14Mb USB-based PLC
 	  (Powerline Communications) solution with an Intellon
-- 
2.54.0

[PATCHv3 net-next 6/9] net: usb: move exported symbols from cdc_ether to usbnet

[Oliver Neukum]

Move the rest of the symbols to usbnet, so that the cdc_ether
driver does not need to be loaded as a library.

Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
 drivers/net/usb/cdc_ether.c | 372 ------------------------------------
 drivers/net/usb/usbnet.c    | 356 ++++++++++++++++++++++++++++++++++
 include/linux/usb/usbnet.h  |  17 ++
 3 files changed, 373 insertions(+), 372 deletions(-)

diff --git a/drivers/net/usb/cdc_ether.c b/drivers/net/usb/cdc_ether.c
index 76ad4ffa950a..6bf6538f3468 100644
--- a/drivers/net/usb/cdc_ether.c
+++ b/drivers/net/usb/cdc_ether.c
@@ -19,378 +19,6 @@
 #include <linux/usb/usbnet.h>
 
 
-#if IS_ENABLED(CONFIG_USB_NET_RNDIS_HOST)
-
-static int is_rndis(struct usb_interface_descriptor *desc)
-{
-	return (desc->bInterfaceClass == USB_CLASS_COMM &&
-		desc->bInterfaceSubClass == 2 &&
-		desc->bInterfaceProtocol == 0xff);
-}
-
-static int is_activesync(struct usb_interface_descriptor *desc)
-{
-	return (desc->bInterfaceClass == USB_CLASS_MISC &&
-		desc->bInterfaceSubClass == 1 &&
-		desc->bInterfaceProtocol == 1);
-}
-
-static int is_wireless_rndis(struct usb_interface_descriptor *desc)
-{
-	return (desc->bInterfaceClass == USB_CLASS_WIRELESS_CONTROLLER &&
-		desc->bInterfaceSubClass == 1 &&
-		desc->bInterfaceProtocol == 3);
-}
-
-static int is_novatel_rndis(struct usb_interface_descriptor *desc)
-{
-	return (desc->bInterfaceClass == USB_CLASS_MISC &&
-		desc->bInterfaceSubClass == 4 &&
-		desc->bInterfaceProtocol == 1);
-}
-
-#else
-
-#define is_rndis(desc)		0
-#define is_activesync(desc)	0
-#define is_wireless_rndis(desc)	0
-#define is_novatel_rndis(desc)	0
-
-#endif
-
-static const u8 mbm_guid[16] = {
-	0xa3, 0x17, 0xa8, 0x8b, 0x04, 0x5e, 0x4f, 0x01,
-	0xa6, 0x07, 0xc0, 0xff, 0xcb, 0x7e, 0x39, 0x2a,
-};
-
-/* We need to override usbnet_*_link_ksettings in bind() */
-static const struct ethtool_ops cdc_ether_ethtool_ops = {
-	.get_link		= usbnet_get_link,
-	.nway_reset		= usbnet_nway_reset,
-	.get_drvinfo		= usbnet_get_drvinfo,
-	.get_msglevel		= usbnet_get_msglevel,
-	.set_msglevel		= usbnet_set_msglevel,
-	.get_ts_info		= ethtool_op_get_ts_info,
-	.get_link_ksettings	= usbnet_get_link_ksettings_internal,
-	.set_link_ksettings	= NULL,
-};
-
-/* probes control interface, claims data interface, collects the bulk
- * endpoints, activates data interface (if needed), maybe sets MTU.
- * all pure cdc, except for certain firmware workarounds, and knowing
- * that rndis uses one different rule.
- */
-int usbnet_generic_cdc_bind(struct usbnet *dev, struct usb_interface *intf)
-{
-	u8				*buf = intf->cur_altsetting->extra;
-	int				len = intf->cur_altsetting->extralen;
-	struct usb_interface_descriptor	*d;
-	struct cdc_state		*info = &dev->cdc;
-	int				status = -ENODEV;
-	int				rndis;
-	bool				android_rndis_quirk = false;
-	struct usb_driver		*driver = driver_of(intf);
-	struct usb_cdc_parsed_header header;
-
-	if (sizeof(dev->data) < sizeof(*info))
-		return -EDOM;
-
-	/* expect strict spec conformance for the descriptors, but
-	 * cope with firmware which stores them in the wrong place
-	 */
-	if (len == 0 && dev->udev->actconfig->extralen) {
-		/* Motorola SB4100 (and others: Brad Hards says it's
-		 * from a Broadcom design) put CDC descriptors here
-		 */
-		buf = dev->udev->actconfig->extra;
-		len = dev->udev->actconfig->extralen;
-		dev_dbg(&intf->dev, "CDC descriptors on config\n");
-	}
-
-	/* Maybe CDC descriptors are after the endpoint?  This bug has
-	 * been seen on some 2Wire Inc RNDIS-ish products.
-	 */
-	if (len == 0) {
-		struct usb_host_endpoint	*hep;
-
-		hep = intf->cur_altsetting->endpoint;
-		if (hep) {
-			buf = hep->extra;
-			len = hep->extralen;
-		}
-		if (len)
-			dev_dbg(&intf->dev,
-				"CDC descriptors on endpoint\n");
-	}
-
-	/* this assumes that if there's a non-RNDIS vendor variant
-	 * of cdc-acm, it'll fail RNDIS requests cleanly.
-	 */
-	rndis = (is_rndis(&intf->cur_altsetting->desc) ||
-		 is_activesync(&intf->cur_altsetting->desc) ||
-		 is_wireless_rndis(&intf->cur_altsetting->desc) ||
-		 is_novatel_rndis(&intf->cur_altsetting->desc));
-
-	memset(info, 0, sizeof(*info));
-	info->control = intf;
-
-	cdc_parse_cdc_header(&header, intf, buf, len);
-
-	info->u = header.usb_cdc_union_desc;
-	info->header = header.usb_cdc_header_desc;
-	info->ether = header.usb_cdc_ether_desc;
-	if (!info->u) {
-		if (rndis) {
-			goto skip;
-		} else {
-			/* in that case a quirk is mandatory */
-			dev_err(&dev->udev->dev, "No union descriptors\n");
-			goto bad_desc;
-		}
-	}
-	/* we need a master/control interface (what we're
-	 * probed with) and a slave/data interface; union
-	 * descriptors sort this all out.
-	 */
-	info->control = usb_ifnum_to_if(dev->udev, info->u->bMasterInterface0);
-	info->data = usb_ifnum_to_if(dev->udev, info->u->bSlaveInterface0);
-	if (!info->control || !info->data) {
-		dev_dbg(&intf->dev,
-			"master #%u/%p slave #%u/%p\n",
-			info->u->bMasterInterface0,
-			info->control,
-			info->u->bSlaveInterface0,
-			info->data);
-		/* fall back to hard-wiring for RNDIS */
-		if (rndis) {
-			android_rndis_quirk = true;
-			goto skip;
-		}
-		dev_err(&intf->dev, "bad CDC descriptors\n");
-		goto bad_desc;
-	}
-	if (info->control != intf) {
-		/* Ambit USB Cable Modem (and maybe others)
-		 * interchanges master and slave interface.
-		 */
-		if (info->data == intf) {
-			info->data = info->control;
-			info->control = intf;
-		} else {
-			dev_err(&intf->dev, "bogus CDC Union\n");
-			goto bad_desc;
-		}
-	}
-
-	/* some devices merge these - skip class check */
-	if (info->control == info->data)
-		goto skip;
-
-	/* a data interface altsetting does the real i/o */
-	d = &info->data->cur_altsetting->desc;
-	if (d->bInterfaceClass != USB_CLASS_CDC_DATA) {
-		dev_err(&intf->dev, "slave class %u\n", d->bInterfaceClass);
-		goto bad_desc;
-	}
-skip:
-	/* Communication class functions with bmCapabilities are not
-	 * RNDIS.  But some Wireless class RNDIS functions use
-	 * bmCapabilities for their own purpose. The failsafe is
-	 * therefore applied only to Communication class RNDIS
-	 * functions.  The rndis test is redundant, but a cheap
-	 * optimization.
-	 */
-	if (rndis && is_rndis(&intf->cur_altsetting->desc) &&
-	    header.usb_cdc_acm_descriptor &&
-	    header.usb_cdc_acm_descriptor->bmCapabilities) {
-		dev_err(&intf->dev,
-			"ACM capabilities %02x, not really RNDIS?\n",
-			header.usb_cdc_acm_descriptor->bmCapabilities);
-		goto bad_desc;
-	}
-
-	if (header.usb_cdc_ether_desc && info->ether->wMaxSegmentSize) {
-		dev->hard_mtu = le16_to_cpu(info->ether->wMaxSegmentSize);
-		/* because of Zaurus, we may be ignoring the host
-		 * side link address we were given.
-		 */
-	}
-
-	if (header.usb_cdc_mdlm_desc &&
-	    memcmp(header.usb_cdc_mdlm_desc->bGUID, mbm_guid, 16)) {
-		dev_err(&intf->dev, "GUID doesn't match\n");
-		goto bad_desc;
-	}
-
-	if (header.usb_cdc_mdlm_detail_desc &&
-		header.usb_cdc_mdlm_detail_desc->bLength <
-			(sizeof(struct usb_cdc_mdlm_detail_desc) + 1)) {
-		dev_err(&intf->dev, "Descriptor too short\n");
-		goto bad_desc;
-	}
-
-
-
-	/* Microsoft ActiveSync based and some regular RNDIS devices lack the
-	 * CDC descriptors, so we'll hard-wire the interfaces and not check
-	 * for descriptors.
-	 *
-	 * Some Android RNDIS devices have a CDC Union descriptor pointing
-	 * to non-existing interfaces.  Ignore that and attempt the same
-	 * hard-wired 0 and 1 interfaces.
-	 */
-	if (rndis && (!info->u || android_rndis_quirk)) {
-		info->control = usb_ifnum_to_if(dev->udev, 0);
-		info->data = usb_ifnum_to_if(dev->udev, 1);
-		if (!info->control || !info->data || info->control != intf) {
-			dev_err(&intf->dev,
-				"rndis: master #0/%p slave #1/%p\n",
-				info->control,
-				info->data);
-			goto bad_desc;
-		}
-
-	} else if (!info->header || (!rndis && !info->ether)) {
-		dev_err(&intf->dev, "missing cdc %s%s%sdescriptor\n",
-			info->header ? "" : "header ",
-			info->u ? "" : "union ",
-			info->ether ? "" : "ether ");
-		goto bad_desc;
-	}
-
-	/* claim data interface and set it up ... with side effects.
-	 * network traffic can't flow until an altsetting is enabled.
-	 */
-	if (info->data != info->control) {
-		status = usb_driver_claim_interface(driver, info->data, dev);
-		if (status < 0) {
-			dev_err(&intf->dev, "Second interface unclaimable\n");
-			goto bad_desc;
-		}
-	}
-	status = usbnet_get_endpoints(dev, info->data);
-	if (status < 0) {
-		dev_dbg(&intf->dev, "Mandatory endpoints missing\n");
-		goto bail_out_and_release;
-	}
-
-	/* status endpoint: optional for CDC Ethernet, not RNDIS (or ACM) */
-	if (info->data != info->control)
-		dev->status = NULL;
-	if (info->control->cur_altsetting->desc.bNumEndpoints == 1) {
-		struct usb_endpoint_descriptor	*desc;
-
-		dev->status = &info->control->cur_altsetting->endpoint[0];
-		desc = &dev->status->desc;
-		if (!usb_endpoint_is_int_in(desc) ||
-		    (le16_to_cpu(desc->wMaxPacketSize)
-		     < sizeof(struct usb_cdc_notification)) ||
-		    !desc->bInterval) {
-			dev_dbg(&intf->dev, "bad notification endpoint\n");
-			dev->status = NULL;
-		}
-	}
-	if (rndis && !dev->status) {
-		dev_err(&intf->dev, "missing RNDIS status endpoint\n");
-		status = -ENODEV;
-		goto bail_out_and_release;
-	}
-
-	/* override ethtool_ops */
-	dev->net->ethtool_ops = &cdc_ether_ethtool_ops;
-
-	return 0;
-
-bail_out_and_release:
-	usb_set_intfdata(info->data, NULL);
-	if (info->data != info->control)
-		usb_driver_release_interface(driver, info->data);
-bad_desc:
-	return status;
-}
-EXPORT_SYMBOL_GPL(usbnet_generic_cdc_bind);
-
-
-/* like usbnet_generic_cdc_bind() but handles filter initialization
- * correctly
- */
-int usbnet_ether_cdc_bind(struct usbnet *dev, struct usb_interface *intf)
-{
-	int rv;
-
-	rv = usbnet_generic_cdc_bind(dev, intf);
-	if (rv < 0)
-		goto bail_out;
-
-	/* Some devices don't initialise properly. In particular
-	 * the packet filter is not reset. There are devices that
-	 * don't do reset all the way. So the packet filter should
-	 * be set to a sane initial value.
-	 */
-	usbnet_cdc_update_filter(dev);
-
-bail_out:
-	return rv;
-}
-EXPORT_SYMBOL_GPL(usbnet_ether_cdc_bind);
-
-void usbnet_cdc_unbind(struct usbnet *dev, struct usb_interface *intf)
-{
-	struct cdc_state		*info = &dev->cdc;
-	struct usb_driver		*driver = driver_of(intf);
-
-	/* combined interface - nothing  to do */
-	if (info->data == info->control)
-		return;
-
-	/* disconnect master --> disconnect slave */
-	if (intf == info->control && info->data) {
-		/* ensure immediate exit from usbnet_disconnect */
-		usb_set_intfdata(info->data, NULL);
-		usb_driver_release_interface(driver, info->data);
-		info->data = NULL;
-	}
-
-	/* and vice versa (just in case) */
-	else if (intf == info->data && info->control) {
-		/* ensure immediate exit from usbnet_disconnect */
-		usb_set_intfdata(info->control, NULL);
-		usb_driver_release_interface(driver, info->control);
-		info->control = NULL;
-	}
-}
-EXPORT_SYMBOL_GPL(usbnet_cdc_unbind);
-
-/* Communications Device Class, Ethernet Control model
- *
- * Takes two interfaces.  The DATA interface is inactive till an altsetting
- * is selected.  Configuration data includes class descriptors.  There's
- * an optional status endpoint on the control interface.
- *
- * This should interop with whatever the 2.4 "CDCEther.c" driver
- * (by Brad Hards) talked with, with more functionality.
- */
-
-int usbnet_cdc_bind(struct usbnet *dev, struct usb_interface *intf)
-{
-	int				status;
-	struct cdc_state		*info = &dev->cdc;
-
-	status = usbnet_ether_cdc_bind(dev, intf);
-	if (status < 0)
-		return status;
-
-	status = usbnet_get_ethernet_addr(dev, info->ether->iMACAddress);
-	if (status < 0) {
-		usb_set_intfdata(info->data, NULL);
-		usb_driver_release_interface(driver_of(intf), info->data);
-		return status;
-	}
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(usbnet_cdc_bind);
-
 static int usbnet_cdc_zte_bind(struct usbnet *dev, struct usb_interface *intf)
 {
 	int status = usbnet_cdc_bind(dev, intf);
diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index 14e9f1b1e0a2..ce932c81382e 100644
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -2369,6 +2369,362 @@ int usbnet_cdc_zte_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
 	return 1;
 }
 EXPORT_SYMBOL_GPL(usbnet_cdc_zte_rx_fixup);
+
+
+#if IS_ENABLED(CONFIG_USB_NET_RNDIS_HOST)
+
+static int is_rndis(struct usb_interface_descriptor *desc)
+{
+	return (desc->bInterfaceClass == USB_CLASS_COMM &&
+		desc->bInterfaceSubClass == 2 &&
+		desc->bInterfaceProtocol == 0xff);
+}
+
+static int is_activesync(struct usb_interface_descriptor *desc)
+{
+	return (desc->bInterfaceClass == USB_CLASS_MISC &&
+		desc->bInterfaceSubClass == 1 &&
+		desc->bInterfaceProtocol == 1);
+}
+
+static int is_wireless_rndis(struct usb_interface_descriptor *desc)
+{
+	return (desc->bInterfaceClass == USB_CLASS_WIRELESS_CONTROLLER &&
+		desc->bInterfaceSubClass == 1 &&
+		desc->bInterfaceProtocol == 3);
+}
+
+static int is_novatel_rndis(struct usb_interface_descriptor *desc)
+{
+	return (desc->bInterfaceClass == USB_CLASS_MISC &&
+		desc->bInterfaceSubClass == 4 &&
+		desc->bInterfaceProtocol == 1);
+}
+
+#else
+
+#define is_rndis(desc)		0
+#define is_activesync(desc)	0
+#define is_wireless_rndis(desc)	0
+#define is_novatel_rndis(desc)	0
+
+#endif
+
+/* Communications Device Class, Ethernet Control model
+ *
+ * Takes two interfaces.  The DATA interface is inactive till an altsetting
+ * is selected.  Configuration data includes class descriptors.  There's
+ * an optional status endpoint on the control interface.
+ *
+ * This should interop with whatever the 2.4 "CDCEther.c" driver
+ * (by Brad Hards) talked with, with more functionality.
+ */
+
+int usbnet_cdc_bind(struct usbnet *dev, struct usb_interface *intf)
+{
+	int				status;
+	struct cdc_state		*info = &dev->cdc;
+
+	status = usbnet_ether_cdc_bind(dev, intf);
+	if (status < 0)
+		return status;
+
+	status = usbnet_get_ethernet_addr(dev, info->ether->iMACAddress);
+	if (status < 0) {
+		usb_set_intfdata(info->data, NULL);
+		usb_driver_release_interface(driver_of(intf), info->data);
+		return status;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(usbnet_cdc_bind);
+
+/* probes control interface, claims data interface, collects the bulk
+ * endpoints, activates data interface (if needed), maybe sets MTU.
+ * all pure cdc, except for certain firmware workarounds, and knowing
+ * that rndis uses one different rule.
+ */
+int usbnet_generic_cdc_bind(struct usbnet *dev, struct usb_interface *intf)
+{
+	u8				*buf = intf->cur_altsetting->extra;
+	int				len = intf->cur_altsetting->extralen;
+	struct usb_interface_descriptor	*d;
+	struct cdc_state		*info = &dev->cdc;
+	int				status = -ENODEV;
+	int				rndis;
+	bool				android_rndis_quirk = false;
+	struct usb_driver		*driver = driver_of(intf);
+	struct usb_cdc_parsed_header header;
+
+	if (sizeof(dev->data) < sizeof(*info))
+		return -EDOM;
+
+	/* expect strict spec conformance for the descriptors, but
+	 * cope with firmware which stores them in the wrong place
+	 */
+	if (len == 0 && dev->udev->actconfig->extralen) {
+		/* Motorola SB4100 (and others: Brad Hards says it's
+		 * from a Broadcom design) put CDC descriptors here
+		 */
+		buf = dev->udev->actconfig->extra;
+		len = dev->udev->actconfig->extralen;
+		dev_dbg(&intf->dev, "CDC descriptors on config\n");
+	}
+
+	/* Maybe CDC descriptors are after the endpoint?  This bug has
+	 * been seen on some 2Wire Inc RNDIS-ish products.
+	 */
+	if (len == 0) {
+		struct usb_host_endpoint	*hep;
+
+		hep = intf->cur_altsetting->endpoint;
+		if (hep) {
+			buf = hep->extra;
+			len = hep->extralen;
+		}
+		if (len)
+			dev_dbg(&intf->dev,
+				"CDC descriptors on endpoint\n");
+	}
+
+	/* this assumes that if there's a non-RNDIS vendor variant
+	 * of cdc-acm, it'll fail RNDIS requests cleanly.
+	 */
+	rndis = (is_rndis(&intf->cur_altsetting->desc) ||
+		 is_activesync(&intf->cur_altsetting->desc) ||
+		 is_wireless_rndis(&intf->cur_altsetting->desc) ||
+		 is_novatel_rndis(&intf->cur_altsetting->desc));
+
+	memset(info, 0, sizeof(*info));
+	info->control = intf;
+
+	cdc_parse_cdc_header(&header, intf, buf, len);
+
+	info->u = header.usb_cdc_union_desc;
+	info->header = header.usb_cdc_header_desc;
+	info->ether = header.usb_cdc_ether_desc;
+	if (!info->u) {
+		if (rndis) {
+			goto skip;
+		} else {
+			/* in that case a quirk is mandatory */
+			dev_err(&dev->udev->dev, "No union descriptors\n");
+			goto bad_desc;
+		}
+	}
+	/* we need a master/control interface (what we're
+	 * probed with) and a slave/data interface; union
+	 * descriptors sort this all out.
+	 */
+	info->control = usb_ifnum_to_if(dev->udev, info->u->bMasterInterface0);
+	info->data = usb_ifnum_to_if(dev->udev, info->u->bSlaveInterface0);
+	if (!info->control || !info->data) {
+		dev_dbg(&intf->dev,
+			"master #%u/%p slave #%u/%p\n",
+			info->u->bMasterInterface0,
+			info->control,
+			info->u->bSlaveInterface0,
+			info->data);
+		/* fall back to hard-wiring for RNDIS */
+		if (rndis) {
+			android_rndis_quirk = true;
+			goto skip;
+		}
+		dev_err(&intf->dev, "bad CDC descriptors\n");
+		goto bad_desc;
+	}
+	if (info->control != intf) {
+		/* Ambit USB Cable Modem (and maybe others)
+		 * interchanges master and slave interface.
+		 */
+		if (info->data == intf) {
+			info->data = info->control;
+			info->control = intf;
+		} else {
+			dev_err(&intf->dev, "bogus CDC Union\n");
+			goto bad_desc;
+		}
+	}
+
+	/* some devices merge these - skip class check */
+	if (info->control == info->data)
+		goto skip;
+
+	/* a data interface altsetting does the real i/o */
+	d = &info->data->cur_altsetting->desc;
+	if (d->bInterfaceClass != USB_CLASS_CDC_DATA) {
+		dev_err(&intf->dev, "slave class %u\n", d->bInterfaceClass);
+		goto bad_desc;
+	}
+skip:
+	/* Communication class functions with bmCapabilities are not
+	 * RNDIS.  But some Wireless class RNDIS functions use
+	 * bmCapabilities for their own purpose. The failsafe is
+	 * therefore applied only to Communication class RNDIS
+	 * functions.  The rndis test is redundant, but a cheap
+	 * optimization.
+	 */
+	if (rndis && is_rndis(&intf->cur_altsetting->desc) &&
+	    header.usb_cdc_acm_descriptor &&
+	    header.usb_cdc_acm_descriptor->bmCapabilities) {
+		dev_err(&intf->dev,
+			"ACM capabilities %02x, not really RNDIS?\n",
+			header.usb_cdc_acm_descriptor->bmCapabilities);
+		goto bad_desc;
+	}
+
+	if (header.usb_cdc_ether_desc && info->ether->wMaxSegmentSize) {
+		dev->hard_mtu = le16_to_cpu(info->ether->wMaxSegmentSize);
+		/* because of Zaurus, we may be ignoring the host
+		 * side link address we were given.
+		 */
+	}
+
+	if (header.usb_cdc_mdlm_desc &&
+	    memcmp(header.usb_cdc_mdlm_desc->bGUID, mbm_guid, 16)) {
+		dev_err(&intf->dev, "GUID doesn't match\n");
+		goto bad_desc;
+	}
+
+	if (header.usb_cdc_mdlm_detail_desc &&
+		header.usb_cdc_mdlm_detail_desc->bLength <
+			(sizeof(struct usb_cdc_mdlm_detail_desc) + 1)) {
+		dev_err(&intf->dev, "Descriptor too short\n");
+		goto bad_desc;
+	}
+
+
+
+	/* Microsoft ActiveSync based and some regular RNDIS devices lack the
+	 * CDC descriptors, so we'll hard-wire the interfaces and not check
+	 * for descriptors.
+	 *
+	 * Some Android RNDIS devices have a CDC Union descriptor pointing
+	 * to non-existing interfaces.  Ignore that and attempt the same
+	 * hard-wired 0 and 1 interfaces.
+	 */
+	if (rndis && (!info->u || android_rndis_quirk)) {
+		info->control = usb_ifnum_to_if(dev->udev, 0);
+		info->data = usb_ifnum_to_if(dev->udev, 1);
+		if (!info->control || !info->data || info->control != intf) {
+			dev_err(&intf->dev,
+				"rndis: master #0/%p slave #1/%p\n",
+				info->control,
+				info->data);
+			goto bad_desc;
+		}
+
+	} else if (!info->header || (!rndis && !info->ether)) {
+		dev_err(&intf->dev, "missing cdc %s%s%sdescriptor\n",
+			info->header ? "" : "header ",
+			info->u ? "" : "union ",
+			info->ether ? "" : "ether ");
+		goto bad_desc;
+	}
+
+	/* claim data interface and set it up ... with side effects.
+	 * network traffic can't flow until an altsetting is enabled.
+	 */
+	if (info->data != info->control) {
+		status = usb_driver_claim_interface(driver, info->data, dev);
+		if (status < 0) {
+			dev_err(&intf->dev, "Second interface unclaimable\n");
+			goto bad_desc;
+		}
+	}
+	status = usbnet_get_endpoints(dev, info->data);
+	if (status < 0) {
+		dev_dbg(&intf->dev, "Mandatory endpoints missing\n");
+		goto bail_out_and_release;
+	}
+
+	/* status endpoint: optional for CDC Ethernet, not RNDIS (or ACM) */
+	if (info->data != info->control)
+		dev->status = NULL;
+	if (info->control->cur_altsetting->desc.bNumEndpoints == 1) {
+		struct usb_endpoint_descriptor	*desc;
+
+		dev->status = &info->control->cur_altsetting->endpoint[0];
+		desc = &dev->status->desc;
+		if (!usb_endpoint_is_int_in(desc) ||
+		    (le16_to_cpu(desc->wMaxPacketSize)
+		     < sizeof(struct usb_cdc_notification)) ||
+		    !desc->bInterval) {
+			dev_dbg(&intf->dev, "bad notification endpoint\n");
+			dev->status = NULL;
+		}
+	}
+	if (rndis && !dev->status) {
+		dev_err(&intf->dev, "missing RNDIS status endpoint\n");
+		status = -ENODEV;
+		goto bail_out_and_release;
+	}
+
+	/* override ethtool_ops */
+	dev->net->ethtool_ops = &cdc_ether_ethtool_ops;
+
+	return 0;
+
+bail_out_and_release:
+	usb_set_intfdata(info->data, NULL);
+	if (info->data != info->control)
+		usb_driver_release_interface(driver, info->data);
+bad_desc:
+	return status;
+}
+EXPORT_SYMBOL_GPL(usbnet_generic_cdc_bind);
+
+/* like usbnet_generic_cdc_bind() but handles filter initialization
+ * correctly
+ */
+int usbnet_ether_cdc_bind(struct usbnet *dev, struct usb_interface *intf)
+{
+	int rv;
+
+	rv = usbnet_generic_cdc_bind(dev, intf);
+	if (rv < 0)
+		goto bail_out;
+
+	/* Some devices don't initialise properly. In particular
+	 * the packet filter is not reset. There are devices that
+	 * don't do reset all the way. So the packet filter should
+	 * be set to a sane initial value.
+	 */
+	usbnet_cdc_update_filter(dev);
+
+bail_out:
+	return rv;
+}
+EXPORT_SYMBOL_GPL(usbnet_ether_cdc_bind);
+
+void usbnet_cdc_unbind(struct usbnet *dev, struct usb_interface *intf)
+{
+	struct cdc_state		*info = &dev->cdc;
+	struct usb_driver		*driver = driver_of(intf);
+
+	/* combined interface - nothing  to do */
+	if (info->data == info->control)
+		return;
+
+	/* disconnect master --> disconnect slave */
+	if (intf == info->control && info->data) {
+		/* ensure immediate exit from usbnet_disconnect */
+		usb_set_intfdata(info->data, NULL);
+		usb_driver_release_interface(driver, info->data);
+		info->data = NULL;
+	}
+
+	/* and vice versa (just in case) */
+	else if (intf == info->data && info->control) {
+		/* ensure immediate exit from usbnet_disconnect */
+		usb_set_intfdata(info->control, NULL);
+		usb_driver_release_interface(driver, info->control);
+		info->control = NULL;
+	}
+}
+EXPORT_SYMBOL_GPL(usbnet_cdc_unbind);
+
 /*-------------------------------------------------------------------------*/
 
 static int __init usbnet_init(void)
diff --git a/include/linux/usb/usbnet.h b/include/linux/usb/usbnet.h
index 79f48eb388ee..b3a77078fb10 100644
--- a/include/linux/usb/usbnet.h
+++ b/include/linux/usb/usbnet.h
@@ -16,6 +16,11 @@
 #include <linux/usb.h>
 #include <linux/spinlock.h>
 
+static const u8 mbm_guid[16] = {
+	0xa3, 0x17, 0xa8, 0x8b, 0x04, 0x5e, 0x4f, 0x01,
+	0xa6, 0x07, 0xc0, 0xff, 0xcb, 0x7e, 0x39, 0x2a,
+};
+
 struct cdc_state {
 	struct usb_cdc_header_desc      *header;
 	struct usb_cdc_union_desc       *u;
@@ -304,4 +309,16 @@ extern void usbnet_status_stop(struct usbnet *dev);
 
 extern void usbnet_update_max_qlen(struct usbnet *dev);
 
+/* We need to override usbnet_*_link_ksettings in bind() */
+static const struct ethtool_ops cdc_ether_ethtool_ops = {
+	.get_link		= usbnet_get_link,
+	.nway_reset		= usbnet_nway_reset,
+	.get_drvinfo		= usbnet_get_drvinfo,
+	.get_msglevel		= usbnet_get_msglevel,
+	.set_msglevel		= usbnet_set_msglevel,
+	.get_ts_info		= ethtool_op_get_ts_info,
+	.get_link_ksettings	= usbnet_get_link_ksettings_internal,
+	.set_link_ksettings	= NULL,
+};
+
 #endif /* __LINUX_USB_USBNET_H */
-- 
2.54.0

Re: [PATCHv3 net-next 6/9] net: usb: move exported symbols from cdc_ether to usbnet

[Jakub Kicinski]

On Tue, 14 Jul 2026 13:44:26 +0200 Oliver Neukum wrote:
> --- a/include/linux/usb/usbnet.h
> +++ b/include/linux/usb/usbnet.h
> @@ -16,6 +16,11 @@
>  #include <linux/usb.h>
>  #include <linux/spinlock.h>
>  
> +static const u8 mbm_guid[16] = {
> +	0xa3, 0x17, 0xa8, 0x8b, 0x04, 0x5e, 0x4f, 0x01,
> +	0xa6, 0x07, 0xc0, 0xff, 0xcb, 0x7e, 0x39, 0x2a,
> +};
> +
>  struct cdc_state {
>  	struct usb_cdc_header_desc      *header;
>  	struct usb_cdc_union_desc       *u;
> @@ -304,4 +309,16 @@ extern void usbnet_status_stop(struct usbnet *dev);
>  
>  extern void usbnet_update_max_qlen(struct usbnet *dev);
>  
> +/* We need to override usbnet_*_link_ksettings in bind() */
> +static const struct ethtool_ops cdc_ether_ethtool_ops = {
> +	.get_link		= usbnet_get_link,
> +	.nway_reset		= usbnet_nway_reset,
> +	.get_drvinfo		= usbnet_get_drvinfo,
> +	.get_msglevel		= usbnet_get_msglevel,
> +	.set_msglevel		= usbnet_set_msglevel,
> +	.get_ts_info		= ethtool_op_get_ts_info,
> +	.get_link_ksettings	= usbnet_get_link_ksettings_internal,
> +	.set_link_ksettings	= NULL,
> +};

spews a ton of defined but not used warnings

[PATCHv3 net-next 7/9] net: usb: remove dependencies on cdc_ether

[Oliver Neukum]

Now that the driver no longer exports symbols to act
as a library for other drivers other drivers don't
depend on it. Remove the dependencies.

Signed-off-by: Oliver Neukum <oneukum@suse.com>
---

v3:
- removed unneeded parantheses

 drivers/net/usb/Kconfig | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/net/usb/Kconfig b/drivers/net/usb/Kconfig
index da0f6a138f4f..732e0d5f331d 100644
--- a/drivers/net/usb/Kconfig
+++ b/drivers/net/usb/Kconfig
@@ -258,7 +258,6 @@ config USB_NET_CDC_EEM
 config USB_NET_CDC_NCM
 	tristate "CDC NCM support"
 	depends on USB_USBNET
-	select USB_NET_CDCETHER
 	default y
 	help
 	  This driver provides support for CDC NCM (Network Control Model
@@ -399,7 +398,6 @@ config USB_NET_MCS7830
 config USB_NET_RNDIS_HOST
 	tristate "Host for RNDIS and ActiveSync devices"
 	depends on USB_USBNET
-	select USB_NET_CDCETHER
 	help
 	  This option enables hosting "Remote NDIS" USB networking links,
 	  as encouraged by Microsoft (instead of CDC Ethernet!) for use in
@@ -494,7 +492,6 @@ config USB_KC2190
 config USB_NET_ZAURUS
 	tristate "Sharp Zaurus (stock ROMs) and compatible"
 	depends on USB_USBNET
-	select USB_NET_CDCETHER
 	select CRC32
 	default y
 	help
@@ -597,7 +594,7 @@ config USB_SIERRA_NET
 
 config USB_VL600
 	tristate "LG VL600 modem dongle"
-	depends on USB_NET_CDCETHER && TTY
+	depends on TTY
 	select USB_ACM
 	help
 	  Select this if you want to use an LG Electronics 4G/LTE usb modem
@@ -634,7 +631,7 @@ config USB_NET_AQC111
 
 config USB_RTL8153_ECM
 	tristate
-	depends on USB_NET_CDCETHER && (USB_RTL8152 || USB_RTL8152=n)
+	depends on USB_RTL8152 || USB_RTL8152=n
 	default y
 	help
 	  This option supports ECM mode for RTL8153 ethernet adapter, when
-- 
2.54.0

[PATCHv3 net-next 8/9] net: usb: usbnet: remove outdated sanity check

[Oliver Neukum]

The cdc state is now included as a proper member in the descriptor.
There is no point in checking whether it fits into the scratchpad
area. Just remove the check.

Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
 drivers/net/usb/usbnet.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index ce932c81382e..0347f6887222 100644
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -2457,9 +2457,6 @@ int usbnet_generic_cdc_bind(struct usbnet *dev, struct usb_interface *intf)
 	struct usb_driver		*driver = driver_of(intf);
 	struct usb_cdc_parsed_header header;
 
-	if (sizeof(dev->data) < sizeof(*info))
-		return -EDOM;
-
 	/* expect strict spec conformance for the descriptors, but
 	 * cope with firmware which stores them in the wrong place
 	 */
-- 
2.54.0

[PATCHv3 net-next 9/9] net: usb: usbnet: corrections in the comments

[Oliver Neukum]

Correct grammar in comments.

Signed-off-by: Oliver Neukum <oneukum@suse.com>
---

v3:
- added to fix concerns about language in comments

 drivers/net/usb/usbnet.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index 0347f6887222..76bbbfb7a24e 100644
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -2351,12 +2351,12 @@ void usbnet_cdc_status(struct usbnet *dev, struct urb *urb)
 }
 EXPORT_SYMBOL_GPL(usbnet_cdc_status);
 
-/* Make sure packets have correct destination MAC address
+/* Make sure packets have the correct destination MAC address
  *
  * A firmware bug observed on some devices (ZTE MF823/831/910) is that the
- * device sends packets with a static, bogus, random MAC address (event if
- * device MAC address has been updated). Always set MAC address to that of the
- * device.
+ * device sends packets with a static, bogus, random MAC address (event if the
+ * device MAC address has been updated). Always set the MAC address to that
+ * of the device.
  */
 int usbnet_cdc_zte_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
 {
-- 
2.54.0

Re: [PATCHv3 net-next 1/9] net: usb: move updating filter and status from cdc drivers to usbnet

[Jakub Kicinski]

On Tue, 14 Jul 2026 13:44:21 +0200 Oliver Neukum wrote:
> These helpers are used by multiple drivers and do not depend
> on the rest. For example rndis_host will also need cdc_ether.
> Leaving them in a cdc driver means that additional drivers are loaded
> just as a library, not to support hardware by themselves.

checkpatch

ERROR: trailing whitespace
#169: FILE: drivers/net/usb/usbnet.c:2316:
+^I^I/* we cannot assume the device is in sync with us*/ $