ALSA troubleshooting grid

Revision as of 15:59, 11 October 2023 by Registered User
Applicable for STM32MP13x lines, STM32MP15x lines

Some typical issues related to the ALSA framework are listed below. Solutions or debugging methods are proposed for these issues.

If your issue is not listed, try also looking in the articles in the ALSA or troubleshooting grids categories.

Symptom Resolution
The sound card does not probe. If one or more audio interfaces are missing, the sound card cannot probe:
- Look for missing audio interfaces in /sys/kernel/debug/asoc/dais.
- Check kernel config, modules and error trace for missing interfaces.
- Check devices not probed in /sys/kernel/debug/devices_deferred.
aplay: pcm_write:2030:
write error: Input/output error

This error occurs on an audio playback, when audio samples are not output. A possible cause is a wrong configuration of the audio interface:

- DAI gpios not activated: missing in DT or in bad state
- DAI/codec not clocked: kernel/master clock not enabled
- No data transfers: DMA misconfigured in DT or in bad state

Refer to Soundcard configuration

Error -16 setting sai_ck parent clock.
Active stream rates conflict

The two SAI sub blocks which are connected to the audio codec, share their master clock on Disco and Evaluation boards. When running both capture and playback on the codec, the chosen sampling rates must be multiple of each other, because of this dependency. If sampling rates are not compatible, an error is issued.