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Subject: Re: [PATCH v5] cdc-acm: fix abnormal DATA RX issue for Mediatek
 Preloader.
From: Macpaul Lin <macpaul.lin@mediatek.com>
To: Lars Melin <larsm17@gmail.com>
CC: Oliver Neukum <oneukum@suse.com>,
        Andrey Arapov <andrey.arapov@gmail.com>,
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Date: Wed, 19 Dec 2018 12:03:23 +0800
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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.

Regards,
Macpaul Lin