From mboxrd@z Thu Jan  1 00:00:00 1970
From: Troy Kisky <troy.kisky@boundarydevices.com>
Subject: Question about snd_dma_buffer  bytes field
Date: Sun, 24 May 2009 19:26:42 -0700
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Does

(substream->dma_buffer.bytes) need to equal (snd_pcm_lib_period_bytes(substream) * runtime->periods) ?

When this is not true, it seems like the buffer is not being filled correctly.


for testing, this works
	.buffer_bytes_max = 16 * 7 * 512,
	.period_bytes_min = 32,
	.period_bytes_max = 7 * 512,	/* This is size of ping + pong buffer*/

and this doesn't.
	.buffer_bytes_max = 16 * 7 * 512 + 512,
	.period_bytes_min = 32,
	.period_bytes_max = 7 * 512,	/* This is size of ping + pong buffer*/


When playing back a sine wave, I can hear breaks.


Thanks
Troy