kern/45701: hdaudio stops working after suspend/resume and then detach/reattach

[Taylor R Campbell <campbell+netbsd%mumble.net@localhost>]

>Number:         45701
>Category:       kern
>Synopsis:       hdaudio stops working after suspend/resume and then 
>detach/reattach
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Dec 09 09:30:00 +0000 2011
>Originator:     Taylor R Campbell <campbell+netbsd%mumble.net@localhost>
>Release:        NetBSD 5.99.56
>Organization:
>Environment:
System: NetBSD oberon.local 5.99.56 NetBSD 5.99.56 (RIAMONOHACK) #0: Sun Oct 16 
07:50:03 UTC 2011 
root@oberon.local:/home/riastradh/netbsd/current/obj/sys/arch/i386/compile/RIAMONOHACK
 i386
Architecture: i386
Machine: i386
>Description:

        On my MacBook, hdaudio works, with a local hack to set the gpio
        pins.  If I suspend/resume, hdaudio continues to work.  But if
        I detach and reattach hdaudio0/hdafg0, either with hdaudioctl
        or by unloading and reloading the hdaudio and hdafg modules,
        then I end up with two extra volume knobs in the mixer, and
        audio ceases to work -- no sound comes out when I try to play
        anything.

        Before:

% mixerctl -av
outputs.master=170,170 volume delta=2
outputs.master.mute=off  [ off on ]
outputs.master2=170,170 volume delta=2
outputs.master2.mute=off  [ off on ]
record.monitor=0,0 volume delta=51
inputs.beep=255,255 volume delta=64
inputs.reclvl=0,0 volume delta=17
inputs.reclvl.mute=off  [ off on ]
outputs.dacsel=DAC01  { DAC01 }
record.source=ADC00  { ADC00 }

        After, there's also outputs.master3 and outputs.master4.
        Repeating the process doesn't seem to add any more knobs than
        that.

        Let me know if you'd like any output from hdaudioctl before or
        after audio gets hosed, or excerpts from dmesg output with or
        without hdaudio debugging options enabled, or the local patch
        I'm using to set the gpio pins.

>How-To-Repeat:

        Boot NetBSD with hdaudio.  Suspend and resume.  Detach and
        reattach hdaudio0/hdafg0.  Attempt to play audio.  Fail.

>Fix:

        Yes, please!