On Fri, 2012-09-14 at 10:13 +0200, Lars-Peter Clausen wrote: > On 09/14/2012 05:26 AM, Vinod Koul wrote: > > On Thu, 2012-09-13 at 17:27 +0200, Lars-Peter Clausen wrote: > >> Hi, > >> > >> Hm... Do you think it would work as well if we implement this by > >> setting the > >> callback for the descriptor to NULL? If the callback is NULL there is > >> nothing to at the end of a transfer/period and the dma engine driver > >> may > >> choose to disable interrupts. This would also benefit non cyclic > >> transfers > >> where the callback is NULL and we do not need add the new parameter to > >> dmaengine_prep_dma_cyclic. > > That will work too.... BUT the idea of no_wake mode in ALSA is that we > > should not have any interrupts, so anything which is going to cause > > interrupts to AP in undesired. The interrupts still happen and it just > > that dmaengine driver is not notifying client. > > Well, the idea was that the driver would disable interrupts if there is no > callback to call, since there would be nothing to do in the interrupt > handler anyway. But I guess the flags approach should work fine as well. Yes we _could_ do that, but this relies on dmaengine driver to have this implicit understanding. Anyone using dmaengine library in ASoC may or may not be aware of this, so i would consider it hackish. Using this flag explicitly makes everyone aware what the intended behaviour is. -- ~Vinod -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
