Hi Peter On 07/20/20 at 12:32pm, Peter Ujfalusi wrote: > Hi, > > On 20/07/2020 12.03, Peter Ujfalusi wrote: > > Hi, > > > > On 14/07/2020 21.03, Jarkko Nikula wrote: > >> Hi > >> > >> On 7/11/20 6:33 AM, Dave Young wrote: > >>> Hi, > >>> > >>> I'm trying to use g_audio on my Nokia N900 with mainline kernel. Seems > >>> it does not work. No sound when I play from a laptop, and also see a > >>> lot of error like below: > >>> [ 4729.557647] omap-mcbsp 49022000.mcbsp: TX Buffer Overflow! > >>> ... > >>> > >> Head 0dc589da873b ("Merge tag 'iommu-fixes-v5.8-rc5' of > >> git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu") records and > >> plays fine here (arecord -f dat |aplay), although I see some of those > >> errors but don't hear any glitches etc. > >> > >> Peter, does above indicate a serious issue or is it perhaps a false > >> alarm on OMAP3 (no audible glitches)? > > > > I need to dig out my n900 or beagleXM, but it is hard to believe it is > > not a result of a glitch. > > The DMA is triggered by McBSP and it should write exactly what McBSP > > expects to be receiving. > > > > I can not recall any changes in the past years which would have > > introduced regressions in McBSP or the sDMA driver. > > I have booted linux-next on my BeagleXM (OMAP3630, McBSP2 <-> twl4030) > and I don't see the TX overflow print. Just to clarify, the sound works well on n900 for normal use cases. The TX overflow only happens when I use it as an usb audio gadget. Because n900 is old, I tried to use it as an external audio device. > > I have checked element and threshold modes and it looks fine. > I'm not sure why we have TX Overflow printed on n900. > > >> I believe you don't have some mixer knob on, N900 audio path is somewhat > >> complex and needs bunch of mixer switches and volumes to be set. I > >> attached my N900 mixer scripts for you to try. > > > > This could be the reason for the silence, I have asoundrc files > > somewhere to restore a 'good' mixer config. > > > >> Set first everything off: > >> ./aic34_scripts/shutdown.sh > >> > >> Then enable internal digital microphone and speakers: > >> ./aic34_scripts/dmic.sh > >> ./aic34_scripts/speakers.sh > >> > >> Hopefully these help you get going :-) > >> > > > > - Péter > > > > Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. > > Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki > > > > - Péter > > Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. > Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki > Thanks Dave