Configuring I2S CMB in AM5729

General Discussion
1

Hello I am trying to check if a Beaglebone AI is getting correctly I2S from a TIDA-1454 so if I try to arecord --device="hw:1,0" -f S16_LE test.wav I get:

debian@beaglebone:/var/lib/cloud9$ arecord --device="hw:1,0" -d 20 -f S16_LE test.wav                                                                                                                                                                             
Recording WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 8000 Hz, Mono
arecord: pcm_read:2145: read error: Input/output error

The card is detected since i get this output from arecord -l:

**** List of CAPTURE Hardware Devices ****
card 1: PCM5102a [PCM5102a], device 0: davinci-mcasp.0-pcm5102a-hifi pcm5102a-hifi-0 []
  Subdevices: 1/1
  Subdevice #0: subdevice #0

or arecord -L :

debian@beaglebone:/var/lib/cloud9$ arecord -L
null
    Discard all samples (playback) or generate zero samples (capture)
onboard
onboard_capture_left
onboard_playback_left
onboard_capture_right
onboard_playback_right
plug_onboard_capture_left
plug_onboard_playback_left
default
sysdefault:CARD=PCM5102a
    PCM5102a,
    Default Audio Device
dmix:CARD=PCM5102a,DEV=0
    PCM5102a,
    Direct sample mixing device
dsnoop:CARD=PCM5102a,DEV=0
    PCM5102a,
    Direct sample snooping device
hw:CARD=PCM5102a,DEV=0
    PCM5102a,
    Direct hardware device without any conversions
plughw:CARD=PCM5102a,DEV=0
    PCM5102a,
    Hardware device with all software conversions

But I dont fully understand the changes that must be made in ALSA configuration since my asound.conf splits channels:

pcm.onboard{
    type hw
    card 0
}
ctl.onboard {
    type hw
    card 0
}

### Dsnoop splited channels
pcm.onboard_capture_left {
     type dsnoop
     ipc_key 32
     slave {
         pcm "onboard"
         channels 2
     rate 48000
         format S32_LE
     }
     bindings.0  0
}
pcm.onboard_playback_left {
     type dmix
     ipc_key 33
     slave {
         pcm "onboard"
         channels 2
     }
     bindings.0  0
}


pcm.onboard_capture_right {
     type dsnoop
     ipc_key 32
     slave {
         pcm "onboard"
         channels 2
     rate 48000
     format S32_LE
     }
     bindings.0  1
}
pcm.onboard_playback_right {
     type dmix
     ipc_key 33
     slave {
         pcm "onboard"
         channels 2
     }
     bindings.0  1
}


### PLUGS ##
### used with darkice
### device = plug:plug_onboard_left
pcm.plug_onboard_capture_left{
        type plug
        slave.pcm "onboard_capture_left"
}
pcm.plug_onboard_playback_left{
        type plug
        slave.pcm "onboard_playback_left"
}

pcm.!default {
    type asym
    playback.pcm "plug_onboard_playback_left"
    capture.pcm "plug_onboard_capture_left"
}

This is where probably I haave to make changes but I dont know which one. Or if there is anything that I am missing just let me know.

Thanks in advance.

2

Hi Mikel,
I’m encountering the same problem, but my error is pcm_read:2152: read error: Input/output error.
Could you have any progress? Btw, I’m using beaglebone black, and I still can’t make it work. I’ve also modified the codec, compiled a kernel and configured ALSA paramaters as detailed in this discussion.

I really appreciate it if you could share some of your experience with this.