[alsa-devel] ASoC: tegra: Does the PCM_TRIGGER_{PAUSE, RESUME} emulation really work?

[Stephen Warren]

On 03/22/2013 10:26 AM, Lars-Peter Clausen wrote:
> 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.

It's quite possible this hasn't been tested, or tested recently. I don't
recall how to test PAUSE/RESUME. Can you enlighten me?

Laxman, can you comment here?