[alsa-devel] no period wakeup support

[Pierre-Louis Bossart]

> Nowadays, is this reasonable to consider disabling the period wakeup as default
> instead of expecting period wakeup by default?

I'd say yes - it's been nearly 10 years since this capability was added, 
and it's quite common across HDaudio, Chrome, Android plaforms.

But considering this as a default doesn't mean it's available in 100% of 
the cases, you still you need to check that

a) the driver is capable of disabling the period wakeup
b) the driver is capable of providing a precise position outside of 
period elapsed events (usually marked with the INFO_BATCH capability).

alsa-lib gives you the means to query both cases.

Note that you also have the case where you cannot disable interrupts but 
can still use timer-based solutions (e.g. for USB audio).

Hope this helps
-Pierre