[alsa-devel] Regression for Lenovo X240 sound in 3.18

[Takashi Iwai]

At Mon, 29 Dec 2014 13:51:36 +0100 (CET),
Jan Engelhardt wrote:
> 
> 
> I have a X240 (without any dock), and in Linux 3.17.4, I used to have
> - "Speaker" with switch and volume bar (in alsamixer),
> - "PCM" with switch and volume bar,
> - the headphone output volume would be controlled by both Master and PCM.
> 
> With 3.18.1, bisected down to below commit, this all went bonkers.
> - "Speaker" has only a switch but no volume bar,

Some volume remapping is an expected side-effect as some outputs share
the same DAC.

> - speakers do not output _any_ sound whatsoever anymore

Are you using PulseAudio or without?  Try to check without PA at
first.  Don't forget to raise / unmute all relevant volumes via
"alsamixer -c0" (or -c1), then test with "aplay -Dplughw foo.wav"
(or aplay -Dplughw:1 foo.wav)

There has been a known issue in the recent openSUSE pulseaudio
package, so this might be it.  In that case, try to upgrade pulseaudio
and related packages from OBS multimedia:libs repo (if not done yet).

> - changing the PCM volume does not affect either Headphone or Speaker.

The "PCM" is now an alsa-lib softvol mixer item that isn't used by
PA.  This is likely no bug.

> commit 7c21539c45eace48e9f6fbdd59347d8416960af5
> Author: Lukas Bossard <mr.bobukas at gmail.com>
> Date:   Wed Oct 29 18:31:07 2014 +0100
> 
>     ALSA: hda - Add ultra dock support for Thinkpad X240.
>     
>     Adding ultra doch support for Lenovo Thinkpad X240 (17aa:2214).
>     [Actually replaced the entry with ALC292_FIXUP_TPT440_DOCK -- tiwai]
> 
> 
> Reverting this commit on top of v3.18.1 restores the sought 
> functionality.

In anyway, get alsa-info.sh outputs at the headphone plugged and
unplugged on both 3.17.x and 3.18.x kernels.  Run the script with
--no-upload option and attach them.


Takashi