From mboxrd@z Thu Jan  1 00:00:00 1970
From: Oliver Neukum <oneukum@suse.de>
Subject: Re: [PATCH net] net: cdc_ncm: workaround for missing CDC Union
Date: Tue, 22 Jan 2013 10:07:07 +0100
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Cc: =?ISO-8859-1?Q?Bj=F8rn?= Mork <bjorn@mork.no>,
	Alexey Orishko <alexey.orishko@gmail.com>,
	"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	"linux-usb@vger.kernel.org" <linux-usb@vger.kernel.org>,
	Greg Suarez <gsuarez@smithmicro.com>
To: Alexey ORISHKO <alexey.orishko@stericsson.com>
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On Monday 21 January 2013 18:59:05 Alexey ORISHKO wrote:
> Specification says: 
> NCM/MBIM shall not send ZLP if buffer size is dwNtbOutMaxSize.
> 
> The problem is: 
> dwNtbOutMaxSize value is negotiated between host and device NCM/MBIM
> entities and usbnet has no knowledge about it.
> 
> Adding one byte to make buffer looking like a short packet was most
> simple approach instead of inventing a way to communicate 
> dwNtbOutMaxSize to usbnet.
> 
> You could drop short packet approach if dwNtbOutMaxSize is provided
> to usbnet and decision is made accordingly to NCM/MBIM spec (with
> exception to faulty devices).

We could do that. Feel free to send a patch. ;-)

	Regards
		Oliver