# [SOLVED] Mute LED not working on HP EliteBook 850 G5

## alogim

I have a HP ElitEBook 850 G5 and on Windows, whenever I muted the audio (F5 key) a small led used to light up. While the key correctly mutes the volume, there is no LED feedback. I have both alsa and pulseaudio installed. When I run alsamixer, I see this, however there is no feedback.

Any help is appreciated. Thanks in advance.

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## NeddySeagoon

alogim,

The kernel has lots of LED drivers. You need to choose the right one, if there is one, for your system.

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## alogim

 *NeddySeagoon wrote:*   

> alogim,
> 
> The kernel has lots of LED drivers. You need to choose the right one, if there is one, for your system.

 

Yes, I know, however I am unable to find the right one, it seems. For example, I found this option (KEYBOARD_ATKBD_HP_KEYCODES), however I am unable to activate it.

Here is the result if I search for it inside menuconfig and here is what I get if I go in that menu.

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## NeddySeagoon

alogim,

I suspect that its separate from the keyboard driver.

You need the right keyboard driver too bet the LED is driven by the kernel separately. You could use the LED to indicate anything.

Have a look on the 

```
  │ Symbol: LEDS_CLASS [=y]                                                          │  

  │ Type  : tristate                                                                 │  

  │ Prompt: LED Class Support                                                        │  

  │   Location:                                                                      │  

  │     -> Device Drivers                                                            │  

  │ (9)   -> LED Support (NEW_LEDS [=y])
```

menu.

If you don't see anything there, press 'z' and the kernel will show you all the hidden options too.

That allows you to read the help to see why they are hidden.

The Depends on: boolean equation must evaluate to true for an option to be selectable.

Many of then are hidden because they don't make sense on x86/amd64

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## alogim

 *NeddySeagoon wrote:*   

> alogim,
> 
> I suspect that its separate from the keyboard driver.
> 
> You need the right keyboard driver too bet the LED is driven by the kernel separately. You could use the LED to indicate anything.
> ...

 

Thank you for your response. LED Support was already enabled, however, after an extensive search on a Ubuntu site collecting errors, I managed to find the solution.

In order to enable the Mute Trigger I had to create a new file /etc/modprobe.d/alsa-base.conf and insert the following content: 

```
options snd-hda-intel model=mute-led-gpio
```

This has solved the problem.

To summarize, when I mute the volume a little led lights up inside the F5 button. Additionally, if I mute the microphone, a little led lights up inside the F8 button too.

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