[alsa-devel] [ALC668]: Asus N751JK - Incorrect default pin assignment for external base speaker and external microphone not working

[Arthur Borsboom]

Hi,

While being in the process of making my audio work on my new notebook, I
noticed that the audio hardware is partially working
out-of-the-Linux-kernel-box v4.0.7 Arch. The following two things seem not
to work.

--------------------------------
1. External base speaker
--------------------------------

The Asus N751JK notebook (ALC668) has a small external 'base' speaker (jack
2,5mm 4 rings), which I only can get to work with the help of hdajackretask
with the following setting:

* Override unconnected pin 0x1a and connect it to Internal Speaker (LFE).

In the sound kernel tree I have noticed PCI ID fixes which are more or less
equal to this situation.
https://git.kernel.org/cgit/linux/kernel/git/tiwai/sound.git/tree/sound/pci/hda/patch_realtek.c

This SND_PCI_QUIRK definition looks a lot like it:
SND_PCI_QUIRK(0x1043, 0x11cd, "Asus N550", ALC662_FIXUP_BASS_1A),

The Vendor/PCI ID is different for this laptop and I guess a new line
should be added something like this:
SND_PCI_QUIRK(0x1043, 0x17bd, "Asus N751JK", ALC662_FIXUP_BASS_1A),

--------------------------------
2. External microphone
--------------------------------

The Asus N751JK notebook (ALC668) has a 3,5mm 4-ring combo jack for
headphones and microphone.
The headphone is detected correct and auto-mute works good (jack detection).
The microphone is not detected and does not work.

I was unable to get it to work with hdajackretask or any of the Asus model
settings, such as:
* options snd_hda_intel model=,asus-mode4

I was able to get the microphone to work with the following setting:
* options snd_hda_intel model=,dell-headset-multi

This setting creates two new items in PulseAudio making a total of three:
* Internal microphone (works out of the box)
* Headset microphone (works indeed with a headset)
* Microphone (don't know if this works, since I don't have a single
microphone, but it does not work with the headset)

Unfortunately the auto-input-device-switch to the Headset microphone does
not seem to work.
When I plugin a headset, the headphones get detected and the Internal
speakers are muted.
The Input device does not automatically switch from Internal microphone to
Headset microphone.
I have to do this manually, after which it works.
I don't know if the microphone has a jack detection.
If it does not, maybe it is possible to use the headphones jack detection?

I have added the alsa-info without any snd_intel / alsa modifications here:
http://www.alsa-project.org/db/?f=0b5135bd12f28bb5cb182f83bfa21bc50022faa6

I don't mind to help to test, for example module options, patches and/or
compile kernels.

Who is able and willing to help to fix this issue?

With kind regards,
Arthur Borsboom.

--
Arthur Borsboom
Email: arthurborsboom at gmail.com