Hi Mark Cc: Laurent Thank you for your feedback > > Current Renesas Sound driver requests DMA channel when .probe timing, > > and release it when .remove timing. And use DMA on .start/.stop > > But, Audio DMAC power ON was handled when request timing (= .probe), > > and power OFF was when release timing (= .remove). > > This means Audio DMAC power is always ON during driver was enabled. > > This patch fixup to request/release DMA channel each time. > > Isn't this something which should be handled by better power management > in the DMA driver rather than this? I discussed about this topic with Laurent. Yes, the best choice is that DMAEngine side should care about it, but, it can't on current DMAEngine design. # We need to call pm_runtime_get_sync() to power the hardware on # which can't be called in atomic context. # And dma_async_issue_pending() needs to be callable in atomic context # so to fix this we would likely need to extend the DMA engine API So, current *better* choice is sound driver request/release DMA channel each time. I will post v2 patch with [1/8] update _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
