CrunchBang Linux

neneko

New Member

Registered: 2012-04-27

Posts: 2

Acer volume slider Q

First of all I'm sorry if this has been posted before but I couldn't find any topic on this specific issue after searching around.

I got a acer aspire 8730G. It got a few shiny media keys with background light and a volume slider. Setting up most of those keys were no problem since they use the normal XF86Audio keys signals. When setting XF86AudioRaiseVolume and XF86AudioLowerVolume to raise and lower the volume the volume jumped around seemingly at random when using the volume slider.

I used xev to see what was going on and it turns out that the volume slider sends both XF86AudioLowerVolume and XF86AudioRaiseVolume in a pattern when you use it. My first idea was to use a keycombo to bind it correctly but that won't work out very well since the sequences it sends isn't fixed length (they're 2-3 keys long).

What's left is to use a keycombo with a very low timeout. After testing a bit with xev again I noticed that the keys within the key sequence sent are sent 10 ms apart and there's a 100ms delay before the next sequence begins.

So to get to my actual question. Is there a program for X/ob that can handle keycombos where you can set a timeout lower than 100 ms? Or would it be easy to write something similar yourself? I haven't really done a lot of programing and never made anything for X but I know enough to make usable console/backend stuff.

If anyone is curious here is the keycombos sent from the volume slider.

The sequence sent depends on the current volume. The slider have 8 'steps' in it. So in the list below the number on the left is the current volume setting.

XF86AudioRaiseVolume = R
XF86AudioLowerVolume = L

Raise:
0: RR
1: LLR
2: RR
3: LLL
4: RR
5: LLR
6: RR
7: LLL

Lower:
8: RRR
7: LL
6: RRL
5: LL
4: RRR
3: LL
2: RRL
1: LL

For example if the volume is at 2 and you slide the volume down to 1 it sends RRL.

So to summarize a bit I'm wondering if there is a program that you can use to bind keycombos where you can set a very low timeout (<100ms). If there isn't any already how hard would it be to make a windowless application that can grab keys globally? I started reading up on xlibs keygrab functions which I assume I will have to use here.

The best solution would obviously be if this whole thing had already been solved but I've been searching quite a bit for a solution to this without finding anything so I don't really have my hopes up on that.

rhowaldt

#!*$%:)

Registered: 2011-03-09

Posts: 4,396

Re: Acer volume slider Q

well, let me start off by saying i do not know how to solve your issue. then of course you are wondering: so what the hell are you replying for? well, the reason is twofold.

1. very nice research you've done there. seems to me you have enough understanding of the problem to be able to successfully script something for it. i just don't know how to go about it.
2. welcome to the community!

now let's hope somebody else comes along with a good solution instead of my social reply

jelloir

#! CrunchBanger

From: Outside the garden wall

Registered: 2009-08-21

Posts: 210

Re: Acer volume slider Q

Before you delve into what looks like a complicated solution have you tried booting with the grub argument "acpi_osi=Linux".  This may not help at all but is worth trying if you haven't already.

Edit /etc/default/grub

Append "acpi_osi=Linux" to the boot arguments (if you have otherarguments such as quiet they are just seperated by spaces).

GRUB_CMDLINE_LINUX_DEFAULT="acpi_osi=Linux"

The update grub.

update-grub

You can also pass the argument on the fly from grub if you like.  Boot with this set and then try xev and see if you get the same volume raise lover events.

---

Debian Sid Desktop Install Guide (Draft)

neneko

New Member

Registered: 2012-04-27

Posts: 2

Re: Acer volume slider Q

Thanks for the welcome and the suggestion.

Sadly the grub idea didn't do anything. I didn't really expect it to since most of the results I got when searching for solutions on this was that the volume slider made the sound jump around at random in windows too. I think the reason for the weird combos sent is that acer want to make sure everyone is using their programs for the laptop to make the volume control work. Since they never made one for linux though here we are.

On the bright side I figured out most Xlib stuff I need by now I think so soon there might be a very hacked together low quality fix for this. I have no idea if acer use the same sort of key combos on other models though so it might only be useful for this specific model.

sherlock_182

New Member

Registered: 2013-04-20

Posts: 1

Re: Acer volume slider Q

Hi there... I know it has been a long time since this thread was started but I wanted to ask how everything went and see if you could offer me any advice. I have the acer aspire 8730G with the touch volume slider.

I recently had some laptop issues so installed windows 7 over the vista that came with the machine.... now my volume slider doesn't work. The mute button does and the stop and forward etc but the slider merely brushes the volume on anything playing not affecting it much in the slightest.

I've tried quite a few things but i'm not very up on acer tech so I don't know what to try now... looks like it's just gunna be a non-usable feature unless you guy know of something I can try. I was hoping maybe there was some way of tampering with the launch manager files perhaps? or ever getting something to trick the system into thinking it is vista and running it as normal.

It was all working fine before the OS change and it surprised me how much i rely on the little slider! Thanks for any help.

Simon.