[alsa-devel] VIA VT1828S hda_intel errors

[Robert Hancock]

On Mon, Nov 2, 2009 at 4:27 AM, Takashi Iwai <tiwai at suse.de> wrote:
> At Sun, 1 Nov 2009 14:03:18 -0600,
> Robert Hancock wrote:
>>
>> On Fri, Oct 30, 2009 at 6:31 AM, Takashi Iwai <tiwai at suse.de> wrote:
>> > At Thu, 29 Oct 2009 19:05:15 -0600,
>> > Robert Hancock wrote:
>> >>
>> >> I've been using the VT1828S codec support from ALSA git for the last few
>> >> weeks. It seems to work fine, but there are some problems showing up in
>> >> dmesg:
>> >>
>> >> Oct 25 20:46:14 newcastle kernel: ALSA sound/pci/hda/hda_intel.c:683: No
>> >> response from codec, disabling MSI: last cmd=0x02af0900
>> >> Oct 25 20:46:15 newcastle kernel: ALSA sound/pci/hda/hda_intel.c:698:
>> >> azx_get_response timeout, switching to polling mode: last cmd=0x02af0900
>> >
>> > Note that this isn't always a severe problem.  If polling mode works
>> > (you don't see the similar errors after this), it means the IRQ isn't
>> > properly generated at verb handling.
>> >
>> >> It seems like the cmd isn't always the same, previously it was
>> >> 0x024f0c00. Is there something bad about this command that could be
>> >> causing the response timeout?
>> >
>> > Hm, both aren't really same, pointing to different widgets.  So,
>> > it looks like a generic problem in the codec communication on your
>> > board.
>>
>> Something VIA guys should look into?
>
> Hopefully.  This is a bit hard problem to track, though...
>
>> >> Also, disabling MSI for one occurrence of
>> >> this seems a bit paranoid..
>> >
>> > MSI was unstable for long time, so disabling it was a sane option :)
>> > Now it gets better, so it should be a second option.
>> > I changed the code now.
>> >
>> >> Also saw one of these:
>> >>
>> >> Oct 26 21:13:20 newcastle kernel: hda-intel: IRQ timing workaround is
>> >> activated for card #0. Suggest a bigger bdl_pos_adj.
>> >>
>> >> and PulseAudio also complained:
>> >>
>> >> Oct 26 00:27:50 newcastle pulseaudio[16530]: alsa-sink.c: ALSA woke us
>> >> up to write new data to the device, but there was actually nothing to write!
>> >> Oct 26 00:27:50 newcastle pulseaudio[16530]: alsa-sink.c: Most likely
>> >> this is a bug in the ALSA driver 'snd_hda_intel'. Please report this
>> >> issue to the ALSA developers.
>> >> Oct 26 00:27:50 newcastle pulseaudio[16530]: alsa-sink.c: We were woken
>> >> up with POLLOUT set -- however a subsequent snd_pcm_avail() returned 0
>> >> or another value < min_avail.
>> >
>> > Well, this is the case where the hardware reports bad position data.
>> > This is usually a hardware bug, and hard to fix properly.  We have some
>> > mechanism to correct or take back to the last position.  This should
>> > usually work, but apparently not in your case...
>>
>> Well, it looks like PulseAudio complained before the IRQ timing
>> workaround was activated (about 20 hours earlier)..
>
> Then try to pass bdl_pos_adj=0 option to snd-hda-intel module.
> The PA complaining still present?

With bdl_pos_adj=0, so far no complaints from PulseAudio after some
hours of audio playing.. I'll keep monitoring it.

Actually there's been no codec response timeout errors either since
making that change, though I don't know if it's just by luck.. doesn't
seem like it should be related.