Oddity with sound handling with recent -current

From: Nik Clayton <nik_at_freebsd.org>
Date: Tue, 14 Sep 2004 11:42:23 +0100
Hi all,

Yesterday I updated my main FreeBSD desktop from -current built 2004.04.27 
to -current built yesterday.  This included migrating from XFree86 to
X.org, updating the nvidia binary drivers, and going from KDE 3.2 to
3.3.

Almost everything went with no real effort on my part.  So kudos to
everyone involved.  The only slight oddity was to do with sound
handling.

I've got

    snd_mss_load="YES"

in /boot/loader.conf, and that continues to work.  However, with the
older current, this gave me /dev/dsp, /dev/pcm, and so on, and the sound
devices were recognised as pcm0 in the probes at boot time.  Here's a 
sample log entry from the 8th (pre-update)

pcm0: <CS423x> at port 0x220-0x22f,0x388-0x38b,0x53 4-0x537 irq 5 drq 3,1 on isa0
pcm0: [GIANT-LOCKED]

Now, after the update, they're recognised as pcm15:

pcm15: <CS423x> at port 0x220-0x22f,0x388-0x38b,0x534-0x537 irq 5 drq 3,1 on isa
0
pcm15: [GIANT-LOCKED]

and the devices in /dev all have a trailing '15' or similar:

    /dev/audio15.0
    /dev/audio15.1
    ...
    /dev/dsp15.0
    /dev/dsp15.1
    ...
    /dev/dspW15.0
    /dev/dspW15.1
    ...

and there's no plain /dev/dsp or /dev/audio devices.  I had to change
/etc/sysctl.conf to now specify:

    hw.snd.pcm15.vchans=4

instead of '...pcm0...', and in KDE's control center, I had to explicitly
specify /dev/dsp15, instead of having it autodetect /dev/dsp.  After
doing that, playback worked fine.

Is this the expected behaviour?  If so, the sound section (7.2) in the
Handbook will need updating.  I've just seen (in snd(4)) the mention of 
hw.snd.unit.  Perhaps if only one sound device is detected this should
automatically be set to the appropriate number (i.e., 15 in my case), 
instead of defaulting to 0?

N
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Received on Tue Sep 14 2004 - 09:39:17 UTC

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