On Thu, Jul 18, 2013 at 01:57:33PM -0500, Joel Fernandes wrote:

On 07/18/2013 12:08 PM, Russell King - ARM Linux wrote:

quoted

As for the maximum number of scatterlist entries, really that's a bug in
the DMA engine implementations if they can't accept arbitary lengths.
I've created DMA engine drivers for implementations where you have to
program each segment individually, ones which can have the current and
next segments, as well as those which can walk a list.  Provided you get
informed of a transfer being completed, there really is no reason for a
DMA engine driver to limit the number of scatterlist entries that it
will accept.

Sure, that makes sense. Can you point to such a typical example
implementation to get some ideas?

MXS MMC driver uses this: drivers/mmc/host/mxs-mmc.c
And dma engine driver for this is mxs-dma.c

~Vinod
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