Re: [PATCH v4 2/2] dma: Add Xilinx zynqmp dma engine driver support
From: Vinod Koul
Date: Sun Aug 23 2015 - 10:06:36 EST
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 <vinod.koul@xxxxxxxxx> 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
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