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

[Lars-Peter Clausen]

On 03/23/2013 12:35 AM, Stephen Warren wrote:
> 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?

Hm, I don't know of an application that is specificity designed to test
pause/resume, but any application using snd_pcm_pause, should be fine.

- Lars