Am Donnerstag, 21. Mai 2015, 11:16:24 schrieb Takashi Iwai:
At Thu, 21 May 2015 10:53:46 +0200,
Martin Steigerwald wrote:
Am Donnerstag, 21. Mai 2015, 06:28:24 schrieb Takashi Iwai:
At Wed, 20 May 2015 16:31:55 +0200,
Martin Steigerwald wrote:
Hello!
On ThinkPad T520 (Intel Sandybridge) with 4.14-rc4 + two BTRFS patches and one Intel P-State debug patch I have no sound output on internal Intel HD audio codec.
According to ThinkPad T520 LED with striked-through speaker the loud speaker is in disabled state. Also KDE´s Phonon says a soundcard is missing. In alsa-mixer I see nothing as MM for muted. If I press the key next to the LED I get a notification on the desktop that loud speaker has been enabled / disabled, but the LED still is on for it being disabled.
I do not hear anything in Amarok or with aplay. alsa-mixer sound volumes are 100 for master and PCM. I also tried with disabling "Auto-Mute Mod", but still no sound.
When I reboot and in BIOS or GRUB press the key then the LED toggles state.
When I reboot into Linux 4.0.1 sound is working fine and loud speaker disabled LED is toggled off, so I bet this is a regression 4.1-rc4 compared to 4.0.1.
Please run alsa-info.sh at both working and non-working cases (with old and new kernels), and attach the outputs. Run the script with --no-upload option.
All attached.
I also have full dmesg outputs available in case it is needed.
Also, such a problem is rather the device permissions problem. Check the device permissions of /dev/snd/* files (also check getfacl /dev/snd/*, too).
If its a permissions problem, why does it happen with 4.1-rc4, but not with 4.0.1 oder any earlier kernels?
I wanted to mean it's rather "often" a permission problem. Not necessarily your case, but still worth to check.
The mute LED behavior change is because of the new control added recently. You seem to have changed the value to "On" while the default should be "Follow Master". This explains the difference of behavior from 4.0. It's no regression but manual misconfiguration by user. In this mode, LED has no connection with the sound output at all.
I didn´t change ALSA configuration on upgrade from 4.0 to 4.1. Can it be it picked "On" as default? Cause I certainly didn´t touch this. Unless it could have been changed on earlier kernels as well. Well then it could be, cause there have been times I tried to set stuff in ALSA for various reasons, but quite some time ago.
I only changed "Auto-Mute Mod" to "disabled" as I tried to debug the muting issue, but other than that I didn´t change
Other than that, no different is seen in the hardware level. The codec registers show all same values. That is, from the driver POV, the sound should work. (Though, you set "Disabled" to "Auto-Mute Mode" control which looks rather weird.)
So, revert "Mute-LED Mode" control to "Follow Master". It can be done via alsamixer, amixer or whatever. Then check whether the sound works again. Check also from the headphone, too.
That works. Thank you. Headphone I will check later.
Ciao,