From mboxrd@z Thu Jan  1 00:00:00 1970
From: Santosh Sivaraj <santoshs@fossix.org>
Subject: a xrun() query
Date: Wed, 11 May 2011 17:40:39 +0530
Message-ID: <20110511121039.GA19108@santoshs.mistral.in>
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Hi,

I am getting glitches while playing audio with aplay. With little
debugging I figured out that the state changes from RUNNING to XRUN at
which time the trigger gets called. I also figured out that XRUN state
is set in the function:

static int snd_pcm_update_hw_ptr_post(struct snd_pcm_substream *substream,
				      struct snd_pcm_runtime *runtime)
{
        <snip>
	} else {
		if (avail >= runtime->stop_threshold) {
			xrun(substream);
			return -EPIPE;
		}
	}
        </snip>
}

I am not able to find out why the condition (avail >
runtime->stop_threshold) becomes true. Can the experts here tell
during what use cases/scenarios this happens?

Thanks,
Santosh

-- 
http://fossix.org, http://dot.slashb.in

Luck is a matter of preparation meeting the opportunity.
					-- Anon