[PATCH] ALSA: compress: allow pause and resume during draining

[Takashi Iwai]

On Mon, 12 Oct 2020 16:46:56 +0200,
Jaroslav Kysela wrote:
> 
> Dne 12. 10. 20 v 16:21 Takashi Iwai napsal(a):
> 
> > But, I doubt whether we really need to care about that; as mentioned
> > earlier, there is little to change from the user-space side.  It just
> > pause or resume.  The only difference is the resume target, and
> > honestly speaking, there is no interest in it from user-space side.
> > And, the rest is about the kernel internal, and this can be really
> > done in the way of the original patch.  The flow is quite simple and
> > understandable...
> 
> The core compress code already uses the state mechanism (although internally).
> 
> Also, it's really unclear if all drivers were checked, if the pause triggers
> can be called from the drain state (I know it's another point, but the drivers
> should probably offer a flag that they support this). And why to call the
> pause release callback when there's no pause (drain + release ioctl instead
> drain + pause + release ioctl)? It's a clear midlevel code fault. This
> protection should be there not in the hw drivers.
> 
> I refer the original patch:
>   https://lore.kernel.org/alsa-devel/000c01d69585$228db6b0$67a92410$@samsung.com/

Point taken, and yes, this should be handled conditionally only for
the drivers that do support such a mode.


Takashi