From: Oliver Neukum <oliver@neukum.org>
To: Greg KH <gregkh@suse.de>
Subject: Re: [PATCH 2/2] USB: ehci: tegra: Align DMA transfers to 32 bytes
Date: Sat, 18 Dec 2010 00:17:40 +0100
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Cc: rmorell@nvidia.com, David Brownell <dbrownell@users.sourceforge.net>,
        Benoit Goby <benoit@android.com>,
        Alan Stern <stern@rowland.harvard.edu>,
        Sarah Sharp <sarah.a.sharp@linux.intel.com>,
        Matthew Wilcox <willy@linux.intel.com>,
        Ming Lei <tom.leiming@gmail.com>, Jacob Pan <jacob.jun.pan@intel.com>,
        Olof Johansson <olof@lixom.net>, Erik Gilling <konkers@android.com>,
        Colin Cross <ccross@android.com>,
        "linux-usb@vger.kernel.org" <linux-usb@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
References: <1292623129-26361-1-git-send-email-rmorell@nvidia.com> <20101217224221.GE25105@morell.nvidia.com> <20101217230940.GB21147@suse.de>
In-Reply-To: <20101217230940.GB21147@suse.de>
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Am Samstag, 18. Dezember 2010, 00:09:40 schrieb Greg KH:
> I still don't like it, it feels like a hack that is not going to be able
> to be maintained very well.
> 
> And I still think the individual drivers should be fixed...
> 

But they are not buggy. The USB API was written under the
assumption that HCDs can deal with byte level granularity and alignment.
Hence the network driver pass DMA-able memory with an alignment
that suits them.

	Regards
		Oliver
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