On Fri, Aug 07, 2015 at 01:23:20PM -0400, Peter Hurley wrote:

The omap-serial driver which doesn't use dma is still the preferred
stable driver for omap, for the moment.

One of the main features of the 8250_omap integration was the addition
of dma support. Without it, 8250_omap is ttyO in ttyS clothing.

Correct.  omap-serial used to have broken DMA support, and I had a
series of patches fixing it.  Unfortunately, despite TI asking me to
work on this, TI went ahead and removed the DMA support behind my
back, which totally screwed my patch series after I merged some of
its pre-requists.  It was then decided that DMA support was no longer
an important feature, so I dropped the patch set.

So, I'm well aware of the issues here, and the problems of using the
OMAP sDMA with the UARTs.

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