Re: CVS commit: src/share/man/man4

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

At Fri, 12 Mar 2021 08:03:24 +0000,
Nia Alarie wrote:
> Committed By:	nia
> Date:		Fri Mar 12 08:03:24 UTC 2021
> 
> Modified Files:
> 	src/share/man/man4: hdaudio.4
> 
> Log Message:
> Clarify problem.
> 
> To generate a diff of this commit:
> cvs rdiff -u -r1.18 -r1.19 src/share/man/man4/hdaudio.4

> @@ -133,5 +133,8 @@
:
> +but these will be converted down to 16-bit before output,  because converting
> +to a hardware precision that isn't a power of two is not yet handled.

This looks incorrect.

MI audio layer synthesizes all streams coming from userland in 16bit,
even if the userland stream has precision higher than 16bit.
MI audio layer can and does handle any precision of underlying
hardware.  For example, the hardware of vraiu(4) on hpcmips (probably)
accepts only 10bit, the hardware of mavb(4) on sgimips (probably)
accepts only 24bit.
If the hardware supports 16bit precision and one or more precision
higher than 16bit like hdafg(4), I think that there is no or less
advantage for MD drivers to choice/support the precision higher than
16bit.

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