Re: CVS commit: src/sys

[Tetsuya Isaki <isaki%pastel-flower.jp@localhost>]

At Fri, 3 Apr 2020 17:48:54 +0200, 
Martin Husemann wrote: 
> > I don't think so.  Each driver/hardware may have their specific 
> > restrictions.  Some driver/hardware may be able to set at 1msec 
> > but others may not.  It's nature.  And this is also why we 
> > should not be eager to reduce default blk_ms. 
>  
> What I meant is that the generic audio system may have a way to query 
> the concrete driver(s) in use for a minimum value they support, and then 
> auto-scales the blk_ms appropriately. 

If you are talking about my previous this text, I maybe
misunderstood.
 > On Fri, Apr 03, 2020 at 09:45:20PM +0900, Tetsuya Isaki wrote:
 > >  But I was not able to set 1msec on yds(4) PCI sound card on

In this case, yds(4) is attached at 5msec automatically.
When attaching, audio layer calculates the blocksize from
AUDI_BLK_MS etc and query it to MD driver (this is round_blocksize
in audio(9)).  If the requested size is too small (or too large)
for the MD driver, it will return alternative blocksize.  If audio
layer can accept it, then use it.
Is this right?

Thanks,
---
Tetsuya Isaki <isaki%pastel-flower.jp@localhost / isaki%NetBSD.org@localhost>