On Wed, Nov 04, 2015 at 06:52:12PM +0100, Roberto Fichera wrote:
I notice your DMA buffer length is very short, which would require very frequency interrupts to service, right? Can you increase your DMA buffer length by increasing the period size? Maybe that would help reduce the likelyhood of a failure.
Not sure if this can help! SSI TDM is set to 32 slots but only 2 are masked. So every frame only 2 slots are pushed/pulled from the FIFOs. maxburst is set to pull a block of 8 elements from the FIFOs, DMA cyclic call it period. So the full DMA buffer is filled in buffer size / period DMA iterations.
A smaller period size may course DMA buffer over/underrun -- ALSA over/underrun even though it seems that you didn't report any.
And apparently SDMA would get more interrupt/callbacks. I would suggest a larger period size and buffer size although I cannot tie your problem with the size. But you may try.