Dell platform adding ucm2 conf with generic mic-mute LEDs feature

[GoPerry]

As the post-patch did, I would need to add one patch for the dell platform which has enabled the generic mic mute feature.
But I did not see the below paths.

/sys/class/sound/ctl-led/speaker
/sys/class/sound/ctl-led/mic

https://www.spinics.net/lists/alsa-devel/msg125821.html

[GoPerry]

root@dell-Latitude-94xx:/sys/module/snd_ctl_led# ll
total 0
drwxr-xr-x 5 root root 0 Jun 28 04:55 ./
drwxr-xr-x 304 root root 0 Jun 23 21:49 ../
-r--r--r-- 1 root root 4096 Jun 28 04:55 coresize
drwxr-xr-x 2 root root 0 Jun 28 04:55 holders/
-r--r--r-- 1 root root 4096 Jun 28 04:57 initsize
-r--r--r-- 1 root root 4096 Jun 28 04:57 initstate
drwxr-xr-x 2 root root 0 Jun 28 04:57 notes/
-r--r--r-- 1 root root 4096 Jun 28 04:55 refcnt
drwxr-xr-x 2 root root 0 Jun 28 04:57 sections/
-r--r--r-- 1 root root 4096 Jun 28 04:57 srcversion
-r--r--r-- 1 root root 4096 Jun 28 04:57 taint
--w------- 1 root root 4096 Jun 28 04:55 uevent

[GoPerry]

snd_ctl_led 24576 0
input_leds 16384 0
ledtrig_audio 16384 4 snd_ctl_led,dell_wmi,snd_sof,dell_laptop

[GoPerry]

@perexg @jwrdegoede

Do I need to add any kernel option to enable the generic mute led ?
Seems like the speaker and mic dirs are not created by default

[jwrdegoede]

You are doing a ll in /sys/module/snd_ctl_led, while you should be doing it in /sys/class/sound/ctl-led.

[GoPerry]

You are doing a ll in /sys/module/snd_ctl_led, while you should be doing it in /sys/class/sound/ctl-led.
Thank you Hans!
correct!
I see the mic and speaker dirs now.

[GoPerry]

root@dell-Latitude-9420:/sys/devices/virtual/sound/ctl-led/mic# echo "follow mute" > mode
root@dell-Latitude-9420:/sys/devices/virtual/sound/ctl-led/mic# ls
brightness card0 mode power uevent
root@dell-Latitude-9420:/sys/devices/virtual/sound/ctl-led/mic# cat mode
follow-mute
root@dell-Latitude-9420:/sys/devices/virtual/sound/ctl-led/mic# cat brightness
1
root@dell-Latitude-9420:/sys/devices/virtual/sound/ctl-led/mic# cat brightness
1
root@dell-Latitude-9420:/sys/devices/virtual/sound/ctl-led/mic# cat brightness
1

did some testing with the ctl-led loaded, the brightsness value is not changed when switching mute/unmute state

[GoPerry]

another problem is that the snd-ctl-led module is not loaded after i add the patch.
Do i need to update alsa-lib ?

[GoPerry]

@jwrdegoede @perexg
Could you help to comment this .

1. the mic and speaker brightness are not changed when switch mic/spk mute state.
2. snd-ctl-led is not loaded automatically after the rt715-sdca/init.conf updated to latest

[perexg]

@GoPerry : You should add configuration like https://www.spinics.net/lists/alsa-devel/msg125821.html to the UCM card. It loads the kernel module and attaches the selected ALSA controls for the LED trigger.

EDIT: The shell commands which are identical to the mentioned UCM config:

• /sbin/modprobe snd_ctl_led
• echo -n "DAC1 Playback Switch" > /sys/class/sound/ctl-led/speaker/card0/attach
• echo -n "ADC Capture Switch" > /sys/class/sound/ctl-led/mic/card0/attach

EDIT2: Changed echo to echo -n.

[GoPerry]

root@dell-Latitude-xx0:/sys/class/sound/ctl-led/mic/card0# echo "ADC Capture Switch" > attach
bash: echo: write error: No such file or directory

root@dell-Latitude-xx0:/sys/class/sound/ctl-led/mic/card0# ls
attach card detach list power reset uevent

It is weird that the attach file cannot be written by this command.

[perexg]

Try echo -n "ADC Capture Switch" > attach .

[perexg]

Also, the control should exists. Use amixer -c 0 controls to get list of controls. Perhaps, you want to attach another one.

[GoPerry]

root@dell-Latitude-9420:/sys/class/sound/ctl-led/mic# ls
brightness card0 mode power uevent
root@dell-Latitude-9420:/sys/class/sound/ctl-led/mic# cat brightness
0
root@dell-Latitude-9420:/sys/class/sound/ctl-led/mic# cat brightness
1
root@dell-Latitude-9420:/sys/class/sound/ctl-led/mic# cat brightness
0
root@dell-Latitude-9420:/sys/class/sound/ctl-led/mic# cat brightness
1

It works for me now with right kcontrol.

[GoPerry]

then the only prolem need to resolve is the ucm2 loading snd_ctl_led.

FixedBootSequence [
exec "-/sbin/modprobe snd_ctl_led"
sysw "-/class/sound/chctl-led/mic/card${CardNumber}/attach:rt714 FU02 Capture Switch"
]

I would like to check where the alsa code will call the FixedBootSequence ?

[GoPerry]

Is it the alsa-lib will trigger the FixedBootSequence ?

[GoPerry]

if alsa-lib trigger the FixedBootSequence, then i would need to upgrade the alsa-lib

[perexg]

You need 1.2.5 alsa-lib and alsa-utils packages. The fixed boot sequence is called from the alsactl utility (invoked via systemd/udev rules).

[perexg]

sysw "-/class/sound/chctl-led/mic/card${CardNumber}/attach:rt714 FU02 Capture Switch"

Typo? It should be class/sound/ctl-led/....

[jwrdegoede]

Note there also is an selinux issue where selinux is blocking alsactl from doing the modprobe:

https://bugzilla.redhat.com/show_bug.cgi?id=1958210

Try setting enforcing=0 on the kernel commandline as a workaround for now.

[GoPerry]

Note there also is an selinux issue where selinux is blocking alsactl from doing the modprobe:

https://bugzilla.redhat.com/show_bug.cgi?id=1958210

Try setting enforcing=0 on the kernel commandline as a workaround for now.

Thank you Hans, let me try disable the selinux

[GoPerry]

sysw "-/class/sound/chctl-led/mic/card${CardNumber}/attach:rt714 FU02 Capture Switch"

Typo? It should be class/sound/ctl-led/....

yeah, typo, the touchpad corrupting the input method.