[alsa-devel] PC speaker beeps in 2.6.30?

[Takashi Iwai]

At Tue, 30 Jun 2009 18:31:30 +0200,
Kurt J. Bosch wrote:
> 
> On 2009-06-30 17:40, Takashi Iwai wrote:
> > At Tue, 30 Jun 2009 17:35:00 +0200,
> > Kurt J. Bosch wrote:
> >>
> >> On 2009-06-30 14:53, Takashi Iwai wrote:
> >>> At Tue, 30 Jun 2009 13:31:07 +0200,
> >>> Kurt J. Bosch wrote:
> >>>>
> >>>> On 2009-06-30 07:57, Takashi Iwai wrote:
> >>>>> At Mon, 29 Jun 2009 16:24:14 -0700,
> >>>>> Paul Vojta wrote:
> >>>>>>
> >>>>>> On Sun, Jun 28, 2009 at 01:09:26PM +0200, Kurt J. Bosch wrote:
> >>>>>>> On 2009-06-28 10:38, Takashi Iwai wrote:
> >>>>>>>> At Sat, 27 Jun 2009 23:39:08 -0700,
> >>>>>>>> Paul Vojta wrote:
> >>>>>>>>>
> >>>>>>>>> On Sat, Jun 27, 2009 at 09:36:42AM +0200, Takashi Iwai wrote:
> >>>>>>>>>> At Fri, 26 Jun 2009 10:03:54 +0400,
> >>>>>>>>>> Michael Tokarev wrote:
> >>>>>>>>>>>
> >>>>>>>>>>> [Adding some more Cc's...]
> >>>>>>>>>>>
> >>>>>>>>>>> Am I the only concerned about this?  My 2.6.30 is still
> >>>>>>>>>>> silent w.r.t. old good PC speaker beeps, and I wasn't
> >>>>>>>>>>> able to make it to produce any sound.  Yes, as pointed
> >>>>>>>>>>> out by others there is a control now, in alsa, and I
> >>>>>>>>>>> can hear ugly and scary beeps from my stereo speakers
> >>>>>>>>>>> (when they're turned on and when the control is un-muted).
> >>>>>>>>>>> But that's.. not a solution/answer to the original
> >>>>>>>>>>> question... ;)
> >>>>>>>>>>
> >>>>>>>>>> Try 2.6.31-rc1.  There was a fix regarding beep frequency.
> >>>>>>>>>
> >>>>>>>>> Not necessarily.  Based on the OP's original post, as well as his mails
> >>>>>>>>> to the LKML (Google the subject line to find them), he has a desktop
> >>>>>>>>> system with external powered speakers connected to a sound card, and also
> >>>>>>>>> a small PC speaker inside the system case.  He wants to hear the beeps
> >>>>>>>>> coming out of the small speaker, since the external speakers (and/or sound
> >>>>>>>>> card) are not always turned on.
> >>>>>>>>
> >>>>>>>> To avoid someone misunderstanding: the beep routed through HD-audio
> >>>>>>>> can also go to the built-in speaker.  It's just mixed up with the
> >>>>>>>> normal audio output, and the volume is controlled via ALSA mixer
> >>>>>>>> volume element.
> >>>>>>>>
> >>>>>>>> But, once after it's hooked up to the codec, the beep can't be output
> >>>>>>>> separately to the speaker.  It's always with other audio signal to the
> >>>>>>>> same output target.
> >>>>>>>>
> >>>>>>>> Or, on some systems (mostly laptops), the beep is hooked up to the
> >>>>>>>> codec automatically no matter whether you set
> >>>>>>>> CONFIG_SND_HDA_INPUT_BEEP once when the codec chip is initialized.
> >>>>>>>> So, the behavior depends pretty much on the hardware implementation.
> >>>>>>>>
> >>>>>>> I face the same problem as the OP since kernel 2.6.30 on ArchLinux on
> >>>>>>> a desktop machine. I was able to get beep working through the built in
> >>>>>>> speaker again by doing a 'modprobe -r pcspkr' followed by a
> >>>>>>> 'modprobe pcspkr' after sysinit. It seems there is some kind of
> >>>>>>> struggle goinig on here between alsa and pcspkr. Isn't there any
> >>>>>>> kernel line or modules configuration option to disable the alsa pc-beep?
> >>>>>>
> >>>>>> Hm... apparently not.  Probably there should be a module option for this, though.
> >>>>>
> >>>>> In the latest sound git tree, you can use "patch" file (passed via
> >>>>> module option) to specify codec-specific setup.
> >>>>> It's for 2.6.32, though.
> >>>>>
> >>>> Sounds rather complicated to me. :)
> >>>> ALSA's snd-hda-intel is stealing the beeps allready 'owned' by pcspkr.
> >>>
> >>> It just adds another beep input device.
> >>>
> >> If that is true both should sound in parallel and then I had to file a bug
> >> against ArchLinux ?
> >
> > It's a feature.
> 
> If one module stealing functionality from the other an vice versa is a 
> feature
> now than I think Linux became some kind of funny video game (like pong) 
> now. LoL

Yes.  It's a designed behavior.  One calls it a "feature".
A feature can be of course bad, worse than other behavior.
But it's a different story.

> >>>> It does
> >>>> this every time it gets [re]loaded. Doing so while lacking a
> >>>> configuration option
> >>>> to disable that behavior is a bug IMHO.
> >>>
> >>> There is a configuration option.
> >>>
> >> But not for the kernel cmdline, right. ;)
> >
> > But you can do it via patch module option (in the later kernel).
> >
> Later kernel ? That's why I keep the earlier kernel packages for
> downgrading. ;)

I guess it's not packaged by distros.

> >>>> (If you use beep to get some alarm
> >>>> notification from hardware sensors or such you will depend on stereo
> >>>> speakers
> >>>> connected and powered on.) Do I miss something ?
> >>>
> >>> Yes.
> >>>
> >> Patching drivers and building my own kernels again as in the old days ?
> >
> > Why not?
> 
> Do you build all your machines (including type writers ans dish washers)
> yourself ? :D

If I need to hack to achieve another feature, I'd do.  Seriously.
That's a goodness of open source.


Takashi