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

Here are the XXX messages:

[   13.722755] sound hdaudioC0D0: XXX hda_fixup_thinkpad_acpi init...
[   13.724366] sound hdaudioC0D0: XXX ok, this is thinkpad
[   13.724373] sound hdaudioC0D0: XXX mute LED NOT WORKING!

This mean that your thinkpad does not support SSMS interface

[   13.724374] sound hdaudioC0D0: XXX ok, mic LED is hooked

This mean that your thinkpad support MMTS interface

http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/driver...

it look like you still need hardware mute gate to turn on/off mute led if there is no other way to turn mute led on/off

but need the MMTS to turn on/off mic mute led

https://lists.launchpad.net/hybrid-graphics-linux/msg01387.html

Do T420 support SSMS interface ?