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Date:   Tue, 24 Aug 2021 13:44:17 +0200
From:   Johan Hovold <johan@kernel.org>
To:     bugzilla-daemon@bugzilla.kernel.org
Cc:     linux-usb@vger.kernel.org
Subject: Re: [Bug 214131] ch341 communication problem
Message-ID: <YSTbkTsOofFkr3CH@hovoldconsulting.com>
References: <bug-214131-208809@https.bugzilla.kernel.org/>
 <bug-214131-208809-j9da9chxlu@https.bugzilla.kernel.org/>
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On Mon, Aug 23, 2021 at 09:14:49AM +0000, bugzilla-daemon@bugzilla.kernel.org wrote:
> https://bugzilla.kernel.org/show_bug.cgi?id=214131
> 
> --- Comment #5 from Paul Größel (pb.g@gmx.de) ---
> I agree, I couldn't find any enumerate related symptoms here:

I was able to reproduce the problem here. The device doesn't send a
zero-length package in case the received data is a multiple of the
endpoint size so that the bulk transfer doesn't complete (e.g. your
flashing application may not receive replies).

We need to revert the offending commit until we can figure out how to
configure the device to send ZLPs.

Thanks again for reporting this, and sorry about the breakage.

Johan