[PATCH RFC 1/2] MUSB: CPPI 4.1 DMA driver (take 4)

[me@felipebalbi.com (Felipe Balbi)]

Hi,

please wrap your mails at 80 characters

On Wed, Dec 30, 2009 at 09:16:08AM +0530, Subbrathnam, Swaminathan
wrote:
> We have been on this front months together now!!! Ideally the place
> holder would be a place independant of platforms as this piece of code
> is more of a platform independant library relating to TI CPPI DMA
> operations.  This would be used during initialization and confiuration
> of CPPI4.x based peripherals.  Though today USB is the only peripheral
> that falls in that catagory ideally other like TI EMAC could fall in
> the same space.
> 
> Having said that I also see that there seems to be no roadmap/plan for
> any other peripheral other than USB to use CPPI4.x in the near future.
> TI EMAC seems to continue use CPPI3.x.
> 
> This was the reason I had recommended earlier to locate this generic
> CPPI 4.x functionality within MUSB.  This definitely helps in having a
> functional peripheral in the near (and most probably long) term.
> 
> I think it is prudent to locate this functionality in the musb
> directory for now.  In future if need arises we can relook at this
> later (I am sure this in all probabilities would not be required).
> 
> In either way I would really appreiciate if we can come to a
> conclusion at the earliest.  Appreciate everybody's feedback and
> direction.

You can do like omap and have the generic dma interface sitting in
mach-davinci, then for musb, you'd have a series of wrappers to use the
cppi dma code. Just look at arch/arm/plat-omap/dma.c and
drivers/usb/musb/tusb6010_omap.c

-- 
balbi