Re: [PATCH] dma: omap-dma: add support for pause of non-cyclic transfers

[Sebastian Andrzej Siewior <bigeasy@linutronix.de>]

On 08/07/2015 06:07 PM, Peter Hurley wrote:
>> If we look at what 8250-dma.c is doing:
>>
>>                 if (dma->rx_running) {
>>                         dmaengine_pause(dma->rxchan);
>>
>> It's 8250-dma.c which is silently _ignoring_ the return code, failing
>> to check that the operation it requested worked.  Maybe this should be
>> WARN_ON(dmaengine_pause(dma->rxchan)) or at least it should print a
>> message?
> 
> Thanks for the suggestion; I'll hold on to that and push it after we add
> the 8250 omap dma pause in mainline.

I have a patch ready with WARN_ON_ONCE() for 8250-omap and 8250-dma.
This warning would trigger on am335x/edma until v4.2-rc1 and omap-dma
based version is open. I could post it if you want me to.
Besides that those two, there are four other drivers ignoring the
return code dmaengine_pause().

Sebastian