[alsa-devel] [PATCH] ALSA: hda/hdmi - add a parameter to let users decide if checking the eld_valid

[Takashi Iwai]

On Mon, 18 Nov 2019 05:40:52 +0100,
Hui Wang wrote:
> 
> 
> On 2019/11/12 下午8:21, Hui Wang wrote:
> >
> > On 2019/11/12 上午12:04, Takashi Iwai wrote:
> >> On Mon, 11 Nov 2019 16:33:45 +0100,
> >> Takashi Iwai wrote:
> >>> On Mon, 11 Nov 2019 15:45:02 +0100,
> >>> Hui Wang wrote:
> >
> [snip]
> >> On the second thought, I wonder whether eld_valid would be corrected
> >> later by the graphics side at all.  If yes, it's a timing issue, and
> >> it can be corrected with the repolling.
> >>
> >> A totally untested patch is below.
> >
> > I will build a testing kernel with this patch and let the bug
> > reporter test it.
> >
> > Thanks,
> >
> > Hui.
> 
> Hello Takashi,
> 
> Tested the patch,  it didn't work. The driver always failed to read
> the speaker allocation from snd_hdmi_get_eld_ati().
> 
> This is the dmesg after adding the patch:
> 
> https://launchpadlibrarian.net/451420819/dmesg (both presence and
> eld_valid bits are set, but can't get the speaker_alloc)

So it's likely a bug in the graphics driver :)

In anyway, it indicates that it's not about eld_valid check itself.
The eld_valid was returned correctly together with the monitor_present
flag.

I guess the system worked casually with your patch to ignore eld_valid
because we don't care much about the channel mapping if channels <= 2.
IOW, another workaround would be to ignore the error if channels <=
2.

But I wonder whether this state persists after this resume moment.
Could you check what happens if you unload / reload the HD-audio
driver?  Does the read of spk_alloc still fail?


thanks,

Takashi

> 
> Regards,
> 
> Hui.
> 
> 
> >
> >
> >>
> >> thanks,
> >>
> >> Takashi
> >>
> >> --- a/sound/pci/hda/patch_hdmi.c
> >> +++ b/sound/pci/hda/patch_hdmi.c
> >> @@ -1549,19 +1549,25 @@ static bool
> >> hdmi_present_sense_via_verbs(struct hdmi_spec_per_pin *per_pin,
> >>               do_repoll = true;
> >>       }
> >>   -    if (do_repoll)
> >> +    do_repoll |= repoll && eld->eld_valid != eld->monitor_present;
> >> +    if (do_repoll) {
> >>           schedule_delayed_work(&per_pin->work, msecs_to_jiffies(300));
> >> -    else
> >> +        ret = false;
> >> +    } else {
> >>           update_eld(codec, per_pin, eld);
> >> -
> >> -    ret = !repoll || !eld->monitor_present || eld->eld_valid;
> >> +        per_pin->repoll_count = 0;
> >> +        ret = true;
> >> +    }
> >>         jack = snd_hda_jack_tbl_get(codec, pin_nid);
> >>       if (jack) {
> >>           jack->block_report = !ret;
> >> -        jack->pin_sense = (eld->monitor_present && eld->eld_valid) ?
> >> -            AC_PINSENSE_PRESENCE : 0;
> >> +        if (ret) {
> >> +            jack->pin_sense = (eld->monitor_present &&
> >> eld->eld_valid) ?
> >> +                AC_PINSENSE_PRESENCE : 0;
> >> +        }
> >>       }
> >> +
> >>       mutex_unlock(&per_pin->lock);
> >>       return ret;
> >>   }
> >>
>