Subject: [PATCH v4 2/2] dma: Add Xilinx zynqmp dma engine driver support

From: [email-masked] (Vinod Koul)
Date: Sun, 23 Aug 2015 19:38:23 +0530

On Thu, Aug 20, 2015 at 12:01:27PM +0530, punnaiah choudary kalluri wrote:
> On Thu, Aug 20, 2015 at 11:43 AM, Vinod Koul <[email-masked]> wrote:
> > On Thu, Aug 06, 2015 at 08:49:33AM +0530, Punnaiah Choudary Kalluri wrote:
> >
> >> +     list_for_each_entry_safe(desc, next, &chan->done_list, node) {
> >> +             dma_async_tx_callback callback;
> >> +             void *callback_param;
> >> +
> >> +             list_del(&desc->node);
> >> +
> >> +             callback = desc->async_tx.callback;
> >> +             callback_param = desc->async_tx.callback_param;
> >> +             if (callback) {
> >> +                     if (in_interrupt())
> >> +                             spin_unlock_bh(&chan->lock);
> >> +                     else
> >> +                             spin_unlock(&chan->lock);
> >
> > This looks bad!
> > Why would callback be called from different context. It should only be
> > invoked from your tasklet
> 
> During the terminate call, driver need to clean up the existing BDs so that time
> this function will be called from the thread or process context in
> addition to the
> tasklet context.
> 
> DO you have any suggestion here ?

Yes you need to terminate but you don't need to invoke user for terminate
flow. It is not expected.
Terminate flow expect youu to clean the channels

-- 
~Vinod