[alsa-devel] [PATCH v2 1/1] alsa-lib: Add snd_pcm_start_at.

[Pierre-Louis Bossart]

>> Do your implementation need to set specific start threshold to prevent
>> the driver automatically start when you fill the buffer ?
>
>
>> Do the driver allow to start when there is no data ?
>>
>
> It's the responsibility of the client to set the start threshold to a
> safe and responsible value.
>
> It might suit some applications to allow both threshold start _and_
> start_at: My implementation doesn't preclude this.

Now I am confused... My understanding was that this feature is similar 
to SSYNC in HDAudio, where everything is ready, buffers filled, DMAs 
armed, FIFOs filled and the start condition only opens the last gate at 
a specific time - possibly with multiple streams starting at the same 
time. If you add a condition on the start_threshold you really don't 
need any hardware-driven start, do you?
Thanks,
-Pierre