[alsa-devel] [pulseaudio-discuss] ThinkPad T-510 audio output mute LED non-workingness

[Takashi Iwai]

At Tue, 28 Apr 2015 04:16:45 -0600,
Glenn Golden wrote:
> 
> Takashi Iwai <tiwai at suse.de> [2015-04-28 08:06:50 +0200]:
> > 
> > It's the call:
> > 	led_set_func(TPACPI_LED_MUTE, false)
> > and this returns an error.  led_set_func is a function pointer to
> > tpacpi_led_set:
> > 	led_set_func = symbol_request(tpacpi_led_set);
> > 
> > So the above indicates that the call in thinkpad_acpi.c failed.
> > 
> > Could you check what value is returned from
> > led_set_func(TPACPI_LED_MUTE, false)?
> > 
> > My wild guess is that it's -ENODEV.
> > 
> 
> Yep: 
> 
>     [   13.379016] sound hdaudioC0D0: XXX hda_fixup_thinkpad_acpi init...
>     [   13.392760] sound hdaudioC0D0: XXX ok, this is thinkpad
>     [   13.404553] sound hdaudioC0D0: XXX mute LED NOT WORKING!
>     [   13.416106] XXX led_set_func(TPACPI_LED_MUTE, false) returned -19
>     [   13.427719] sound hdaudioC0D0: XXX ok, mic LED is hooked

Then it's likely an issue in thinkpad_acpi.c.  It implies that the
driver couldn't get SSMS acpi handle.


> Question: To simplify/speed debugging going forward: Is there some
> straightforward way to unload/reload all the relevant sound modules as
> an alternative to rebooting?  I came across some 'recipes', but none
> looked straightforward; lots of conditionality on the particular subset
> of modules being patched/debugged, but alas I've not enough knowledge
> to guess at exactly what that subset should be for what we're doing here.)

For HD-audio, you need to unload the codec drivers at first, e.g.
   modprobe -r snd-hda-codec-conexant
   modprobe -r snd-hda-codec-hdmi

then unload the control driver, snd-hda-intel
   modprobe -r snd-hda-intel

These will unload the whole sound modules, supposing that you have
only HD-audio.


Takashi