[alsa-devel] Headphones not detected when using Dell Dock WD15

[Tanu Kaskinen]

On Tue, 2017-05-09 at 11:00 +0200, Takashi Iwai wrote:
> On Tue, 09 May 2017 10:52:56 +0200,
> Sergio Villar Senin wrote:
> > 
> > O Mar, 09-05-2017 ás 10:37 +0200, Takashi Iwai escribiu:
> > > On Tue, 09 May 2017 10:32:19 +0200,
> > > Sergio Villar Senin wrote:
> > > > 
> > > > O Mar, 09-05-2017 ás 08:15 +0200, Takashi Iwai escribiu:
> > > > > On Mon, 08 May 2017 11:34:33 +0200,
> > > > > Sergio Villar Senin wrote:
> > > > > > 
> > > > > > Hi,
> > > > > > 
> > > > > > I reported this bug to pulseaudio[1] but after some
> > > > > > investigation
> > > > > > it
> > > > > > looks like the alsa mixer is not working for the dock.
> > > > > > 
> > > > > > I'll be happy to provide any additional info which might be
> > > > > > required
> > > > > > (attaching alsa-info.sh BTW). Please add me to the Cc as I am
> > > > > > not
> > > > > > subscribed to this list
> > > > > 
> > > > > Did you try to update the dock BIOS?
> > > > > The old BIOS on some Dell docks had a few known issues.
> > > > 
> > > > I tried with a virtual machine but the firmware update program
> > > > crashes
> > > > for some reason. Anyway the dock seems to be working fine because
> > > > the
> > > > Windows virtual machine properly detects the headphones when
> > > > plugged
> > > > in.
> > > 
> > > Well, it's a USB-audio device and it doesn't give the jack detection
> > > control like HD-audio.
> > 
> > Not sure about the next step. Do you need additional information to
> > solve the issue? Are you saying that it's a HW issue and that alsa is
> > not going to provide any fix? I'm a bit confused.
> 
> In general Linux USB-audio driver doesn't provide the jack detection
> control.  If any, it's vendor-specific.

The problem is not just that jack detection doesn't work, the problem
is that the mixer doesn't work at all:

$ amixer -c1
amixer: Mixer hw:1 load error: Invalid argument

I would expect the USB-audio driver to provide a mixer control for
choosing the routing, unless that's implemented in some non-standard
way too. As it stands, PulseAudio has no control over the routing, so
the headphone output apparently can't be used at all.

-- 
Tanu

https://www.patreon.com/tanuk