2011/1/16 torsten.schenk torsten.schenk@zoho.com
Hello,
I'm currently developing a driver for a card. PCM playback works so far, I just encountered some playback issues when firefox (flash) and another alsa client wanted to play back at the same time. I figured out that the difference between my driver and existing ones is, that my driver only allows one client and others multiple. I get a "Device or resource busy" when I play back two times the same file (also different ones of course) with mplayer f.ex.
if your sound card 's DSP can mix more than one audio stream, you need to specify the number of playback streams in snd_pcm_new()
int snd_pcm_new(struct snd_card *card, const char *id, int device, int playback_count, int capture_count, struct snd_pcm **rpcm);
otherwise you will need to use a sound server or dmix for software mixing