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 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

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