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Date: Wed, 15 Sep 2010 14:18:47 +0400
From: Sergei Shtylyov <sshtylyov@mvista.com>
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To: Ming Lei <tom.leiming@gmail.com>
CC: Sergei Shtylyov <sshtylyov@mvista.com>, balbi@ti.com,
        "greg@kroah.com" <greg@kroah.com>,
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        David Brownell <dbrownell@users.sourceforge.net>,
        "Gadiyar, Anand" <gadiyar@ti.com>, Mike Frysinger <vapier@gentoo.org>
Subject: Re: [RESEND/PATCH 5/6] USB: musb-gadget: complete request only if
 data is transfered over
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Hello.

On 15-09-2010 14:14, Ming Lei wrote:

>>>> I didn't say it was duplicate for DMA, just too late.

>>> how come ? we need to send ZLP before giving back the request.

>>    Well, look at the code ionce again. We need to send ZLP *after*
>> request->actual == request->length, but as the check is inserted after the
>> ZLP send, ZLP *may* be sent once the first DMA completes, not the last.

> Yes, it is really a problem, as said by balbi.  And the problem should be
> in the check for zlp or the 'is_dma' condition.

> But this patch is not addressed for the zlp problem, and is is only for
> completing the request only if the data transfer in usb_request
> is over, as explained before, right?

    I don't see why we should fix only this problem, while it's obvious tha 
the fix is incomplete and leaves the other problem exposed. Please recast the 
patch.

WBR, Sergei