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From: Arnd Bergmann <arnd@arndb.de>
To: Timur Tabi <timur@freescale.com>
Subject: Re: ucc_uart: add support for Freescale QUICCEngine UART
Date: Wed, 5 Dec 2007 00:26:07 +0100
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On Tuesday 04 December 2007, Timur Tabi wrote:
> When I program the DMA controller, I give it a dma_addr_t. =A0And yet, th=
e DMA=20
> controller and the QE are both devices on the SoC. =A0So if the DMA contr=
oller=20
> takes a dma_addr_t, then shouldn't the QE also take one?
>=20

=46rom a code clarity perspective, the interesting point is that dma_addr_t=
 is
what comes back from the functions in dma-mapping.h. If you don't use them,
a physical address is phys_addr_t.

You can argue that the QS is really a DMA device, but in that case you
should convert the driver to use the DMA mapping interfaces correctly,
which I would consider overkill.

	Arnd <><