[alsa-devel] Newbie needs help to understand SNDRV_PCM_TRIGGER_START?

Radivoje Jovanovic radivojejovanovic at gmail.com
Mon Oct 18 19:28:11 CEST 2010

I am writing my first ALSA driver. We have hardware where the amp is
controlled with another CPU (non Linux) so I have to forward the buffers
from ALSA to it. We do not have working solution on another CPU so I cannot
test sound playback yet. ALSA hits trigger method in my driver and soon
after it leaves my trigger method throws an null pointer exception (probably
since I did not do anything in my trigger method). I am wondering if the
ALSA will call  SNDRV_PCM_TRIGGER_START every single time new buffer is
available. Do I need to manage circular queue of buffers or ALSA is doing
this for me already?

More information about the Alsa-devel mailing list