From 8b4375878ae845a8b5e672cdcf7e38dcfdef508e Mon Sep 17 00:00:00 2001
From: =?utf8?q?Bj=C3=B8rn=20Mork?= <bjorn@mork.no>
Date: Thu, 3 Mar 2016 22:20:53 +0100
Subject: [PATCH] cdc_ncm: toggle altsetting to force reset before setup
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[ 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 <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2: hard-code 1 for data_altsetting]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Reading git-format-patch failed