From mboxrd@z Thu Jan  1 00:00:00 1970
From: Lars-Peter Clausen <lars@metafoo.de>
Subject: ASoC: tegra: Does the PCM_TRIGGER_{PAUSE,
 RESUME} emulation really work?
Date: Fri, 22 Mar 2013 17:26:00 +0100
Message-ID: <514C8618.9070307@metafoo.de>
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To: Stephen Warren <swarren@wwwdotorg.org>, Laxman Dewangan <ldewangan@nvidia.com>
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Hi,

The tegra pcm driver tries to emulate SNDRV_PCM_TRIGGER_PAUSE and
SNDRV_PCM_TRIGGER_RESUME. By passing SNDRV_PCM_TRIGGER_START and
SNDRV_PCM_TRIGGER_STOP to snd_dmaengine_pcm_trigger. But does this really
work? The old non-dmaengine based driver implemented this properly. I'd
reset the dma position pointer for SNDRV_PCM_TRIGGER_START, but keep it
where it was for SNDRV_PCM_TRIGGER_RESUME. But as far as I can see with the
dmaengine based driver the pointer always gets reset to 0 for both
SNDRV_PCM_TRIGGER_START and SNDRV_PCM_TRIGGER_RESUME.

- Lars