[alsa-devel] Loud pops from Intel HDA onboard sound, may damage speakers (fwd)

[Kailang]

Hi Takashi,

 Attachment was the patch that refference by snapshot 2011.03.25.

   Fixed & Update List:
    patch_realtek.c
   - ALC662
           - Fixed ALC66x pop noise on suspend and resume.

    This patch that I test on Acer NB. The result is better than before.
    Could you know how to pull EAPD to low on power down state?

Best Regards,
Kailang

----- Original Message ----- 
From: Takashi Iwai
To: Kailang
Cc: Chris Wilson ; Wu Fengguang ; Pshou ; andy.kopp at intel.com ; 
dan.d.kogan at intel.com ; alsa-devel at alsa-project.org
Sent: Friday, March 25, 2011 3:52 PM
Subject: Re: Loud pops from Intel HDA onboard sound, may damage speakers 
(fwd)


At Fri, 25 Mar 2011 15:43:55 +0800,
Kailang wrote:
>
>
> > ALC269 has some workarounds using COEF magic.  Maybe there is a
> > similar trick for ALC663.  Kailang, do you know of it?
>
> ALC663 has no this control bits like ALC269.
> But it can use EAPD to control it.
> The EAPD pull low before suspend.
> When the resume back, run the EAPD to pull high first.
>
> I could send the patch for you later.

Thanks.

I vaguely remember that this was tried for other codecs but didn't
give good results (rather worse).  Anyway let's check again.


Takashi

>
> Kailang
>
> ----- Original Message ----- 
> From: Takashi Iwai
> To: Chris Wilson
> Cc: Wu Fengguang ; Pshou ; Kailang ; andy.kopp at intel.com ;
> dan.d.kogan at intel.com ; alsa-devel at alsa-project.org
> Sent: Friday, March 25, 2011 3:00 PM
> Subject: Re: Loud pops from Intel HDA onboard sound, may damage speakers
> (fwd)
>
>
> At Thu, 24 Mar 2011 22:41:47 +0000 (GMT),
> Chris Wilson wrote:
> >
> > Hi Takashi and all,
> >
> > On Thu, 24 Mar 2011, Takashi Iwai wrote:
> >
> > >>> Does this happen with 2.6.38 kernel, too?
> > >>
> > >> I have not tried yet, do you have reason to think it may have changed
> > >> since 2.6.32?
> > >
> > > Lots of changes since 2.6.32.  I won't be surprised if any of them 
> > > hits.
> > >
> > >> Can I build just the sound driver without replacing the whole kernel?
> > >
> > > You can try alsa-driver tarball.
> >
> > Unfortunately, I can confirm that stock 2.6.38 does NOT resolve the pops
> > on suspend and resume.
>
> OK, then did you try to set option power_save_controller=0 for
> snd-hda-intel?
>
> ALC269 has some workarounds using COEF magic.  Maybe there is a
> similar trick for ALC663.  Kailang, do you know of it?
>
>
> thanks,
>
> Takashi
>
> ------Please consider the environment before printing this e-mail.
> 
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