Hi Geert > >> > SYS/RT/Audio DMAC have both TCR/TCRB register. > >> > Its difference is transfer counter value of read (= TCR) > >> > or write (= TCRB). The relationship is like below. > >> > > >> > TCR TCRB > >> > [SOURCE] -> [DMAC] -> [DESTINATION] > >> > > >> > Thus, we want to read TCRB instead of TCR for residue. > >> > Otherwise, Sound Capture has noise after PluseAudio support > >> > (= 07b7acb51d2 ("ASoC: rsnd: update pointer more accurate")) > >> > > >> > Signed-off-by: Hiroyuki Yokoyama <hiroyuki.yokoyama.vx@xxxxxxxxxxx> > >> > [Kuninori: added detail information in log] > >> > Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@xxxxxxxxxxx> > > (snip) > >> However, shouldn't the register to use depend on the DMA direction? > > > > I think TCRB is OK for all direction, > > but yes, we can care its direction. > > I can post v2 patch, if you want. > > Geert do you want to care direction ? > > Please do. I think in general the .get_residue() callback should return the > correct value for both reading and writing. OK, will post v2 Best regards --- Kuninori Morimoto -- 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