On Tue, Jan 17, 2012 at 02:37:10PM +0530, Viresh Kumar wrote:

On 1/17/2012 2:22 PM, Linus Walleij wrote:

quoted

Basically the driver using the dmaengine shall map/unmap buffers
used for slave transfers, not the driver.

I usually map them before setting up a transfer and unmaps them
when egtting the callback from the DMA engine that the transfer is
complete.

You implemented similar stuff in amba-pl08x :) .

if (!plchan->slave)
	pl08x_unmap_buffers(txd);

Take a look at that.  "If *NOT* slave, unmap the buffers".  That is in
keeping with what I've been saying.  Slave transfers *do* *not* get
automatic buffer unmapping.