From mboxrd@z Thu Jan  1 00:00:00 1970
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: libata and DMA quirks
Date: Fri, 27 Jun 2008 19:29:43 +1000
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To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: linux-ide@vger.kernel.org, Jeff Garzik <jgarzik@pobox.com>, Tejun Heo <htejun@gmail.com>

On Fri, 2008-06-27 at 09:54 +0100, Alan Cox wrote:
> > a) =EF=BB=BFFor any ATAPI DMA, If the transfer size is not a multip=
le of 16
> > bytes, switch to PIO for this command.
>=20
> Old IDE does this internally. Tejun has done a lot of this stuff for =
the
> ATAPI layer in libata. See the check_atapi_dma method (example at
> it821x_check_atapi_dma with a size rule)

 .../...

Thanks Alan. I'll look at those various examples and sort things
out.

Cheers,
Ben.