Re: [PATCH] dmaengine: ti: omap-dma: Configure LCH_TYPE for OMAP1

From: Aaro Koskinen
Date: Fri Nov 23 2018 - 13:58:32 EST


Hi,

On Fri, Nov 23, 2018 at 02:35:04PM +0200, Peter Ujfalusi wrote:
> On 22/11/2018 17.12, Russell King - ARM Linux wrote:
> > I'm also not sure about this:
> >
> > if (cpu_is_omap15xx())
> > end++;
> >
> > in dma_dest_len() - is that missing from the omap-dma driver? It looks
> > like a work-around for some problem on OMAP15xx, but I can't make sense
> > about why it's in the UDC driver rather than the legacy DMA driver.
>
> afaik no other legacy drivers were doing similar thing, this must be
> something which is needed for the omap_udc driver to fix up something?

Here's the patch that added it: https://marc.info/?l=linux-omap&m=119634396324221&w=2

"Make DMA-OUT behave on the 1510 ... the 1510 CPC register was just
off-by-one with respect to the 1611 CDAC"

A.