Bug 16582

Summary: ALSA doesn't recognize internal microphone on Eeepc 901
Product: Drivers Reporter: Sebastian Dalfuß (sd)
Component: Sound(ALSA)Assignee: Jaroslav Kysela (perex)
Status: RESOLVED OBSOLETE    
Severity: normal CC: alan, tiwai
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: 2.6.35 Subsystem:
Regression: No Bisected commit-id:
Attachments: Content of /proc/asound/card0/codec#0
alsa-info output

Description Sebastian Dalfuß 2010-08-13 18:10:14 UTC
Created attachment 27436 [details]
Content of /proc/asound/card0/codec#0

ALSA doesn't recognize the internal microphone on Eeepc 901. I have a "Mic Boost" setting in the alsa mixer, but nothing like "i-mic", or anything else to enable recording from microphone.

One part of /proc/asound/card0/codec#0 (full content in attachment) appears to be strange:

===8<===

Node 0x12 [Pin Complex] wcaps 0x400001: Stereo
  Pincap 0x00000020: IN
  Pin Default 0x99a30920: [Fixed] Mic at Int ATAPI
    Conn = ATAPI, Color = Unknown
    DefAssociation = 0x2, Sequence = 0x0
    Misc = NO_PRESENCE
  Pin-ctls: 0x20: IN

===8<===

Are there any kernel boot parameters or hwdep configs to try to work around this bug?
Comment 1 Takashi Iwai 2010-08-15 17:12:52 UTC
The fact that there is no "Mic" mixer element is no bug.  Since your machine has only an internal and an external-mic jack, the driver switches the input automatically and provides no capture-source switch.

What is strange in the codec output at all?

Does the recording from the external mic work?  The bug description is too vague for further analysis.

Also, please give alsa-info.sh output (run with --no-upload option) instead of codec proc file.  See Documentation/sounds/alsa/HD-Audio.txt for details.
Comment 2 Sebastian Dalfuß 2010-08-18 04:56:38 UTC
Recording from the internal mic did not work, all I got was silence, despite the recording volume being maxed. (arecord gave me a wav consisting only of a constant stream of 0x80).
I have no external mic to try.

The problem seems to be volume related: I have to turn the mixer element labeled "Capture" down and up a bit (after every boot, reproducible) to make it work. (I found out about that after my initial report). If I just leave it at the desired volume (=max.), all I get is silence.
Comment 3 Sebastian Dalfuß 2010-08-18 04:58:17 UTC
Created attachment 27494 [details]
alsa-info output
Comment 4 Takashi Iwai 2010-08-18 05:26:15 UTC
ALC269 audio input widget shows an unusual amp volume range.  This might be related.  But going to silent sounds odd, still.

Could you give alsa-info.sh output at working volume for comparison, too?

Also, for testing, run like
    % aplay -vv -Dplughw -fdat -c1 foo.wav
then try at max volume.