Commit 67d1a895 authored Mar 25, 2025 by Lubomir Rintel Committed by Jakub Kicinski Mar 27, 2025

rndis_host: Flag RNDIS modems as WWAN devices

Set FLAG_WWAN instead of FLAG_ETHERNET for RNDIS interfaces on Mobile
Broadband Modems, as opposed to regular Ethernet adapters.

Otherwise NetworkManager gets confused, misjudges the device type,
and wouldn't know it should connect a modem to get the device to work.
What would be the result depends on ModemManager version -- older
ModemManager would end up disconnecting a device after an unsuccessful
probe attempt (if it connected without needing to unlock a SIM), while
a newer one might spawn a separate PPP connection over a tty interface
instead, resulting in a general confusion and no end of chaos.

The only way to get this work reliably is to fix the device type
and have good enough version ModemManager (or equivalent).

Fixes: 63ba395c ("rndis_host: support Novatel Verizon USB730L")
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Link: https://patch.msgid.link/20250325095842.1567999-1-lkundrak@v3.sk

Signed-off-by: Jakub Kicinski <kuba@kernel.org>

parent 23f00807

drivers/net/usb/rndis_host.c

+14 −2

Original line number	Diff line number	Diff line
		@@ -630,6 +630,16 @@ static const struct driver_info zte_rndis_info = {
		.tx_fixup = rndis_tx_fixup,
		};

		static const struct driver_info wwan_rndis_info = {
		.description = "Mobile Broadband RNDIS device",
		.flags = FLAG_WWAN \| FLAG_POINTTOPOINT \| FLAG_FRAMING_RN \| FLAG_NO_SETINT,
		.bind = rndis_bind,
		.unbind = rndis_unbind,
		.status = rndis_status,
		.rx_fixup = rndis_rx_fixup,
		.tx_fixup = rndis_tx_fixup,
		};

		/-------------------------------------------------------------------------/

		static const struct usb_device_id products [] = {
		@@ -666,9 +676,11 @@ static const struct usb_device_id products [] = {
		USB_INTERFACE_INFO(USB_CLASS_WIRELESS_CONTROLLER, 1, 3),
		.driver_info = (unsigned long) &rndis_info,
		}, {
		/* Novatel Verizon USB730L */
		/* Mobile Broadband Modem, seen in Novatel Verizon USB730L and
		* Telit FN990A (RNDIS)
		*/
		USB_INTERFACE_INFO(USB_CLASS_MISC, 4, 1),
		.driver_info = (unsigned long) &rndis_info,
		.driver_info = (unsigned long)&wwan_rndis_info,
		},
		{ }, // END
		};