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    Subject[PATCH 3.16 023/217] usb: retry reset if a device times out
    3.16.35-rc1 review patch.  If anyone has any objections, please let me know.

    ------------------

    From: Oliver Neukum <oneukum@suse.com>

    commit 264904ccc33c604d4b3141bbd33808152dfac45b upstream.

    Some devices I got show an inability to operate right after
    power on if they are already connected. They are beyond recovery
    if the descriptors are requested multiple times. So in case of
    a timeout we rather bail early and reset again. But it must be
    done only on the first loop lest we get into a reset/time out
    spiral that can be overcome with a retry.

    This patch is a rework of a patch that fell through the cracks.
    http://www.spinics.net/lists/linux-usb/msg103263.html

    Signed-off-by: Oliver Neukum <oneukum@suse.com>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
    ---
    drivers/usb/core/hub.c | 8 +++++++-
    1 file changed, 7 insertions(+), 1 deletion(-)

    --- a/drivers/usb/core/hub.c
    +++ b/drivers/usb/core/hub.c
    @@ -4370,7 +4370,13 @@ hub_port_init (struct usb_hub *hub, stru
    r = -EPROTO;
    break;
    }
    - if (r == 0)
    + /*
    + * Some devices time out if they are powered on
    + * when already connected. They need a second
    + * reset. But only on the first attempt,
    + * lest we get into a time out/reset loop
    + */
    + if (r == 0 || (r == -ETIMEDOUT && j == 0))
    break;
    }
    udev->descriptor.bMaxPacketSize0 =
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