Commit 245d2119 authored Dec 14, 2017 by Bjørn Mork Committed by David S. Miller Dec 15, 2017

qmi_wwan: set FLAG_SEND_ZLP to avoid network initiated disconnect



It has been reported that the dummy byte we add to avoid
ZLPs can be forwarded by the modem to the PGW/GGSN, and that
some operators will drop the connection if this happens.

In theory, QMI devices are based on CDC ECM and should as such
both support ZLPs and silently ignore the dummy byte.  The latter
assumption failed.  Let's test out the first.

Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 82f67bc6

drivers/net/usb/qmi_wwan.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -826,7 +826,7 @@ err:

		static const struct driver_info qmi_wwan_info = {
		.description = "WWAN/QMI device",
		.flags = FLAG_WWAN,
		.flags = FLAG_WWAN \| FLAG_SEND_ZLP,
		.bind = qmi_wwan_bind,
		.unbind = qmi_wwan_unbind,
		.manage_power = qmi_wwan_manage_power,
		@@ -835,7 +835,7 @@ static const struct driver_info qmi_wwan_info = {

		static const struct driver_info qmi_wwan_info_quirk_dtr = {
		.description = "WWAN/QMI device",
		.flags = FLAG_WWAN,
		.flags = FLAG_WWAN \| FLAG_SEND_ZLP,
		.bind = qmi_wwan_bind,
		.unbind = qmi_wwan_unbind,
		.manage_power = qmi_wwan_manage_power,

Admin message