From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?utf-8?Q?Bj=C3=B8rn_Mork?= Subject: Re: [PATCH net-next] qmi_wwan: set FLAG_SEND_ZLP to avoid network initiated disconnect Date: Thu, 14 Dec 2017 22:42:52 +0100 Message-ID: <87374df0kj.fsf@miraculix.mork.no> References: <20171214185550.15779-1-bjorn@mork.no> <20171214213959.GC21058@vskrishn2-linux.qualcomm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Cc: netdev@vger.kernel.org, linux-usb@vger.kernel.org To: Vamsi Samavedam Return-path: Received: from canardo.mork.no ([148.122.252.1]:37557 "EHLO canardo.mork.no" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752154AbdLNVm4 (ORCPT ); Thu, 14 Dec 2017 16:42:56 -0500 In-Reply-To: <20171214213959.GC21058@vskrishn2-linux.qualcomm.com> (Vamsi Samavedam's message of "Thu, 14 Dec 2017 13:39:59 -0800") Sender: netdev-owner@vger.kernel.org List-ID: Vamsi Samavedam writes: > On Thu, Dec 14, 2017 at 07:55:50PM +0100, Bj=C3=B8rn Mork wrote: >> 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. >>=20 >> 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. >>=20 >> Signed-off-by: Bj=C3=B8rn Mork >> --- >> I am a bit worried about the effect of this change on all the >> devices I can't test myself. But trying it is the only way we >> can ever find out.... > > flag zlp is tested with pids: 9034,9048,904c,9075, 908E,9079, > 908A,909F and 90A4. In general, qualcomm usb firmware can > handle zlps. Thanks. That's very good to know. Bj=C3=B8rn