[alsa-devel] Internal speakers not working on HP ProBook 455 G2

[Takashi Iwai]

At Tue, 24 Feb 2015 17:43:10 +0900,
Michel D4nzer wrote:
> 
> 
> Takashi-san,
> 
> 
> On 19.02.2015 20:38, Takashi Iwai wrote:
> > At Thu, 19 Feb 2015 15:24:15 +0900,
> > Michel D4nzer wrote:
> >>
> >> the built-in speakers of my HP ProBook 455 G2 are not working by
> >> default. I'm attaching the output of alsa-info.sh.
> > 
> > Is this a regression from earlier kernels?
> 
> No, it's the same with Debian's default 3.16 kernel.

What about even older one?

> >> In pavucontrol, the speakers appear as "Speakers (unavailable)", and in
> >> the GNOME sound settings they don't appear at all.
> 
> In the meantime, I've noticed that those symptoms are due to the
> headphone jack being incorrectly detected as connected. And indeed, on a
> different laptop I get all the same symptoms while headphones are
> plugged in.
> 
> So, it occurred to me to try 'the other OS' on this laptop, and the
> behaviour there is weird as well: No sound from the speakers even while
> nothing's plugged into the headphone jack. When I plug in headphones,
> there's a notification: "Something was just unplugged from your
> headphone jack" (!), then sound works as expected through the
> headphones. When I unplug them again, there's a notification: "Something
> was just plugged into your headphone jack".

So the plug state is inverted?


> In Linux, I haven't seen any visible change when plugging in or out the
> headphones.

You can watch the output of "alsactl monitor".

> Do you think the hardware is defective? Any possible workarounds for the
> incorrect headphone jack detection?

The question is whether it's an unreliable jack detection (sometimes /
always doesn't report the event) or the jack detection is inverted by
some reason (plug / unplug swapped).  In the latter case, you can set
a hint "inv_jack_detect = 1".  See
Documentation/sound/alsa/HD-Audio.txt, the section "Hint Strings",
"HD-Audio Reconfiguration" and "Early Patching" sections.


Takashi