From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752610AbcDZSSG (ORCPT ); Tue, 26 Apr 2016 14:18:06 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:56214 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752501AbcDZSSC (ORCPT ); Tue, 26 Apr 2016 14:18:02 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: =?UTF-8?q?Bj=C3=B8rn=20Mork?= , "David S . Miller" , Kamal Mostafa Subject: [PATCH 4.2.y-ckt 07/93] cdc_ncm: toggle altsetting to force reset before setup Date: Tue, 26 Apr 2016 11:16:07 -0700 Message-Id: <1461694653-29506-8-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1461694653-29506-1-git-send-email-kamal@canonical.com> References: <1461694653-29506-1-git-send-email-kamal@canonical.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-Extended-Stable: 4.2 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.2.8-ckt9 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: =?UTF-8?q?Bj=C3=B8rn=20Mork?= [ Upstream commit 48906f62c96cc2cd35753e59310cb70eb08cc6a5 ] Some devices will silently fail setup unless they are reset first. This is necessary even if the data interface is already in altsetting 0, which it will be when the device is probed for the first time. Briefly toggling the altsetting forces a function reset regardless of the initial state. This fixes a setup problem observed on a number of Huawei devices, appearing to operate in NTB-32 mode even if we explicitly set them to NTB-16 mode. Signed-off-by: Bjørn Mork Signed-off-by: David S. Miller Signed-off-by: Kamal Mostafa --- drivers/net/usb/cdc_ncm.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c index f49d684f..f5715cc 100644 --- a/drivers/net/usb/cdc_ncm.c +++ b/drivers/net/usb/cdc_ncm.c @@ -845,7 +845,11 @@ advance: iface_no = ctx->data->cur_altsetting->desc.bInterfaceNumber; - /* reset data interface */ + /* Reset data interface. Some devices will not reset properly + * unless they are configured first. Toggle the altsetting to + * force a reset + */ + usb_set_interface(dev->udev, iface_no, data_altsetting); temp = usb_set_interface(dev->udev, iface_no, 0); if (temp) { dev_dbg(&intf->dev, "set interface failed\n"); -- 2.7.4