On Wed, Aug 02, 2023 at 08:02:29PM +0800, Shengjiu Wang wrote:
On Wed, Aug 2, 2023 at 7:22 PM Takashi Iwai tiwai@suse.de wrote:
Well, I personally don't mind to have some audio capability in v4l2 layer. But, the only uncertain thing for now is whether this is a must-have or not.
Thanks, I am also not sure about this. I am also confused that why there is no m2m implementation for audio in the kernel. Audio also has similar decoder encoder post-processing as video.
This is the thing where we've been trying to persuade people to work on replacing DPCM with full componentisation for about a decade now but nobody's had time other than Morimoto-san who's been chipping away at making everything component based for a good chunk of that time. One trick is that we don't just want this to work for things that are memory to memory, we also want things where there's a direct interconnect that bypasses memory for off-SoC case.
The reason why I select to extend v4l2 for such audio usage is that v4l2 looks best for this audio m2m implementation. v4l2 is designed for m2m usage. if we need implement another 'route', I don't think it can do better that v4l2.
I appreciate that someone can share his ideas or doable solutions. And please don't ignore my request, ignore my patch.
There's a bunch of presentations Lars-Peter did at ELC some considerable time ago about this.