[PATCH RFC 08/26] dmaengine: omap-dma: consolidate setup of CCR

[Russell King - ARM Linux]

On Wed, Jan 22, 2014 at 06:25:57PM +0530, Sricharan R wrote:
> Setting up of DMA_DST_SYNC_PREFETCH is missing after this ?

I'm not looking for the DMA engine driver to be a 100% reimplementation
of the legacy driver.  Rather than supporting the entire set of features
which the legacy driver did, and have many of them simply not used, the
approach I'm taking here is to only support what is necessary for the
drivers we have in mainline - and what fits the DMA engine interfaces.

There is no point inventing new DMA engine interfaces for features for
which we have no users in mainline kernel - to try to do that will be
quite rightfully thrown out by the DMA engine maintainers.

Here's the total number of references/definitions of DMA_DST_SYNC_PREFETCH
in the mainline kernel:

arch/arm/plat-omap/dma.c:               if (src_or_dst_synch == OMAP_DMA_DST_SYNC_PREFETCH) {
include/linux/omap-dma.h:#define OMAP_DMA_DST_SYNC_PREFETCH     0x02

Hence, this feature is unused at present.

-- 
FTTC broadband for 0.8mile line: 5.8Mbps down 500kbps up.  Estimation
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Estimate before purchase was "up to 13.2Mbit".