Vinod Koul <vinod.koul@xxxxxxxxx> writes: > On Wed, Dec 07, 2016 at 04:44:55PM +0000, Måns Rullgård wrote: >> Vinod Koul <vinod.koul@xxxxxxxxx> writes: >> >> >> >> What you're proposing, Vinod, is to make a channel exclusive >> >> to a driver, as long as the driver has not explicitly released >> >> the channel, via dma_release_channel(), right? >> > >> > Precisely, but yes the downside of that is concurrent access are >> > limited, but am not sure if driver implements virtual channels and >> > allows that.. >> >> My driver implements virtual channels. The problem is that the physical >> dma channels signal completion slightly too soon, at least with >> mem-to-device transfers. Apparently we need to keep the sbox routing >> until the peripheral indicates that it has actually received all the >> data. > > So do we need concurrent accesses by all clients. Depends on what people do with the chips. -- Måns Rullgård -- 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
