From mboxrd@z Thu Jan  1 00:00:00 1970
From: Clemens Ladisch <clemens@ladisch.de>
Subject: Re: Is calling snd_pcm_sw_params() mandatory ?
Date: Mon, 29 Nov 2010 09:14:49 +0100
Message-ID: <4CF360F9.9040309@ladisch.de>
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To: Raymond Yau <superquad.vortex2@gmail.com>
Cc: ALSA Development Mailing List <alsa-devel@alsa-project.org>
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Raymond Yau wrote:
> Does alsa-lib has any check whether the application had called snd_pcm_sw_params() or
> it provide default values for those software parameters (e.g. start_threshold, stop_threshold)

The internal snd_pcm_sw_params_default() function does this:

	params->tstamp_mode = SND_PCM_TSTAMP_NONE;
	params->period_step = 1;
	params->sleep_min = 0;
	params->avail_min = pcm->period_size;
	params->xfer_align = 1;
	params->start_threshold = 1;
	params->stop_threshold = pcm->buffer_size;
	params->silence_threshold = 0;
	params->silence_size = 0;


Regards,
Clemens