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Subject: Re: [PATCH v5] cdc-acm: fix abnormal DATA RX issue for Mediatek
 Preloader.
From: Oliver Neukum <oneukum@suse.com>
To: Macpaul Lin <macpaul.lin@mediatek.com>,
        Lars Melin <larsm17@gmail.com>
Cc: Andrey Arapov <andrey.arapov@gmail.com>,
        Johan Hovold <johan@kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Mediatek WSD Upstream <wsd_upstream@mediatek.com>,
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Date: Wed, 19 Dec 2018 09:56:22 +0100
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On Mi, 2018-12-19 at 12:03 +0800, Macpaul Lin wrote:
> On Wed, 2018-12-19 at 10:31 +0700, Lars Melin wrote:
> > On 12/19/2018 10:16, Macpaul Lin wrote: 
> > 
> > Hi Macpaul,
> > your verbose usb listing show me that Mediatek has made two different 
> > 0e8d:003 devices, see my verbose lsusb listing below.
> > (Notice also the reverse order for cmd and data interfaces in it 
> > compared to yours).
> > USB id's are intended to identify a device and its needs so there should
> > never be more than one unique device per id.
> > 
> > 
> > Fairphone FP-1, MT6227  (no CDC union !!!)
> > 
> 
> Hi Lars,
> 
> Ha ha ha, it is a little bit embarrassing.
> What I've used to capture verbose log is MT6765 platform.
> Then I've checked Fairphone FP-1, which is MT6589 a pretty old platform.
> The BROM (boot ROM) has been maintained by other teams and will vary by
> different SoC project in Mediatek. I'm not sure why they changed the
> descriptors.
> 
> For the consistency of BROM's behavior, I'll update a new patch keeps
> PID:0003 remain untouched. I'll trying to report it to BROM team and see
> if they have any action on this issue.

Thank you all for taking care of these important issues.
Please submit that new patch.

	Regards
		Oliver