net: usb: cdc_mbim: add flag FLAG_SEND_ZLP

[ Upstream commit 9f7c728332e8966084242fcd951aa46583bc308c ]

Testing Telit LM940 with ICMP packets > 14552 bytes revealed that
the modem needs FLAG_SEND_ZLP to properly work, otherwise the cdc
mbim data interface won't be anymore responsive.

Signed-off-by: Daniele Palmas <dnlplm@gmail.com>
Acked-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/usb/cdc_mbim.c b/drivers/net/usb/cdc_mbim.c
index 7220cd62071726b171ab2ae792f672d7b513343b..0362acd5cdcaaf2debe7ab13941a06d1504ad21c 100644 (file)
--- a/drivers/net/usb/cdc_mbim.c
+++ b/drivers/net/usb/cdc_mbim.c
@@ -609,7 +609,7 @@ static const struct driver_info cdc_mbim_info_ndp_to_end = {
  */
 static const struct driver_info cdc_mbim_info_avoid_altsetting_toggle = {
        .description = "CDC MBIM",
-       .flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN,
+       .flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN | FLAG_SEND_ZLP,
        .bind = cdc_mbim_bind,
        .unbind = cdc_mbim_unbind,
        .manage_power = cdc_mbim_manage_power,