Hello all.

I'm running mainline 4.1.0 on a Beaglebone Black (TI AM3359 SOC). The board has a standard TI TLV320AIC codec connected via the B3 rev B audio cape: (http://elinux.org/CircuitCo:Audio_Cape_RevB)

Loading the nominally correct device tree overlay gets the following kernel log (1).

An aplay -l listing (2) shows something recognized is present.

Lsmod (3) shows what looks like a sane collection of prerequisite modules.

Upon trying to play a test file the kernel gets a number of buffer underflow/underrun messages (4)

There was a patch posted here (http://mailman.alsa-project.org/pipermail/alsa-devel/2014-November/083797.h tml) which appears to have made it into 4.1.0.

Any thoughts on where to start looking to fix?

More info can be provided if required and can also check hardware pin activity.

Any pointers much appreciated.

TAIA

Jerry.

-----------------------------------snip (1)

root@arm:/home/debian# echo BB-BONE-AUDI-02 > /sys/devices/platform/bone_capemgr/slots

[ 100.654019] bone_capemgr bone_capemgr: part_number 'BB-BONE-AUDI-02', version 'N/A'

[ 100.662117] bone_capemgr bone_capemgr: slot #4: override

[ 100.667840] bone_capemgr bone_capemgr: Using override eeprom data at slot 4

[ 100.675221] bone_capemgr bone_capemgr: slot #4: 'Override Board Name,00A0,Override Manuf,BB-BONE-AUDI-02'

[ 100.712198] bone_capemgr bone_capemgr: slot #4: dtbo 'BB-BONE-AUDI-02-00A0.dtbo' loaded; overlay id #0

root@arm:/home/debian# [ 101.015982] davinci_evm ocp:sound: ASoC: CPU DAI (null) not registered

[ 101.023017] davinci_evm ocp:sound: snd_soc_register_card failed (-517)

[ 101.056114] 2-0018 supply IOVDD not found, using dummy regulator

[ 101.067907] 2-0018 supply DVDD not found, using dummy regulator

[ 101.074535] 2-0018 supply AVDD not found, using dummy regulator

[ 101.080746] 2-0018 supply DRVDD not found, using dummy regulator

[ 101.089316] davinci_evm ocp:sound: ASoC: CODEC DAI tlv320aic3x-hifi not registered

[ 101.097310] davinci_evm ocp:sound: snd_soc_register_card failed (-517)

[ 101.114161] davinci_evm ocp:sound: tlv320aic3x-hifi <-> 48038000.mcasp mapping ok

-----------------------------------snip (2)

root@arm:/home/debian# aplay -l

**** List of PLAYBACK Hardware Devices ****

card 0: EVM [DA830 EVM], device 0: AIC3X tlv320aic3x-hifi-0 []

Subdevices: 1/1

Subdevice #0: subdevice #0

-----------------------------------snip (3)

root@arm:/home/debian# lsmod

Module Size Used by

snd_soc_davinci_mcasp 14407 2

snd_soc_tlv320aic3x 40077 1

snd_soc_edma 1150 1 snd_soc_davinci_mcasp

snd_soc_evm 4802 0

snd_soc_omap 2573 1 snd_soc_davinci_mcasp

snd_soc_core 156839 5 snd_soc_davinci_mcasp,snd_soc_edma,snd_soc_omap,snd_soc_tlv320aic3x,snd_soc_ evm

snd_compress 11858 1 snd_soc_core

snd_pcm_dmaengine 5065 2 snd_soc_core,snd_soc_omap

snd_pcm 85645 5 snd_soc_davinci_mcasp,snd_soc_core,snd_soc_omap,snd_soc_tlv320aic3x,snd_pcm_ dmaengine

snd_timer 17058 1 snd_pcm

snd 58469 4 snd_soc_core,snd_timer,snd_pcm,snd_compress

soundcore 6861 1 snd

omap_aes 13065 0

omap_sham 19198 0

tda998x 11695 1

tilcdc 27899 0

omap_rng 4354 0

drm_kms_helper 106679 3 tda998x,tilcdc

rng_core 7266 1 omap_rng

uio_pdrv_genirq 3317 0

uio 8350 1 uio_pdrv_genirq

leds_gpio 3110 0

-----------------------------------snip (4)

debian@arm:~$ aplay sine2s.wav

Playing WAVE 'sine2s.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo

[ 618.068355] davinci-mcasp 48038000.mcasp: Transmit buffer underflow

underrun!!! (at least 0.410 ms long)

[ 618.092511] davinci-mcasp 48038000.mcasp: Transmit buffer underflow

underrun!!! (at least 11.824 ms long)

[ 618.121692] davinci-mcasp 48038000.mcasp: Transmit buffer underflow

underrun!!! (at least 3.200 ms long)

[ 618.134323] davinci-mcasp 48038000.mcasp: Transmit buffer underflow