Hello, On Wed, 15 Jun 2016 22:11:31 +0530, Vinod Koul wrote: > > This is probably the only thing that I have not changed. The mv_xor > > driver is already using the same strategy, and enqueuing in > > issue_pending() would force us to add the request to a temporary linked > > list, which would be dequeued in issue_pending(). This is quite a bit > > of additional processing, while pushing the new requests directly to > > the engine works fine. > > Well that is wrong! And patch is welcome for mv_xor as well :) > > The DMAengine API mandates that we should submit a descriptor to a queue and > then push them by invoking issue_pending. > > The users are also expected to follow this I have just sent a v4 that fixes this for the mv_xor_v2 driver. Now, in ->tx_submit() we only fill in the HW descriptors, but do not tell the engine to process them. It's only at ->issue_pending() time that we tell the engine that there N new descriptors to process. I'll have a look at mv_xor a bit later. Thanks! Thomas -- Thomas Petazzoni, CTO, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
