PDA

View Full Version : [ubuntu] Lenovo U160: how do I disable SSC?



gamma-andromedae
July 12th, 2011, 01:46 PM
Hello everybody,

yesterday, I quite successfully installed Ubuntu 11.04 (64bit) on my Lenovo U160.

So far, I've encountered only two (obviously well-known) compatibility issues.

The WLAN problem was easily solved by blacklisting acer_wmi.

The second issue, concerning the U160 resuming from suspend mode with a backlit, but blank screen, can, as far as I understand the related discussions, be worked around by putting the line

options i915.lvds_use_ssc=0

in some config file in /etc/modprobe.d ... is that correct so far?

What I (as a newbie) don't understand is *where* exactly I have to put this line?

Is it OK to create a new file 'i915-disable-ssc.conf' inside modprobe.d that contains just that one line!? Or do I have to 'sudo nano' this line to another, already existing config file!?

Thank you for any hint and kind regards,

gamma-andromedae
Wedel near Hamburg, Germany

SunMade
July 13th, 2011, 09:35 AM
I disabled both suspend and and hibernate this way:

1. open a terminal window pressing ctrl-alt-t

2. copy-paste or type this:
gksudo gedit /usr/share/polkit-1/actions/org.freedesktop.upower.policy

3. In the text find the <allow_active> tag and change "yes" to "no" for both suspend and hibernate

4. save the text and reboot


Also I blacklisted acer_wmi this way:

1. open a terminal window pressing ctrl-alt-t

2. copy-paste or type this:
gksudo gedit /etc/modprobe.d/blacklist.conf

3. In the text insert this line:
blacklist acer_wmi

4. save the text and reboot

BUT still the BCM4313 wifi was hardware blocked!!! (rfkill list).
Finally I found this so-called "hardware button" blocking the wifi in some special Lenovo popup-menu i windows 7 when you press Fn-F5

So I need to have the windows 7 that came with this Lenovo laptop installed only to switch on my wifi if it somehow gets hardware blocked again - very annoying and waste of diskspace.

In windows 7 partition handling I managed to shrink windows and recovery, so I have 350GB left for ubuntu (dual-boot). My harddrive is 500GB originally.

gamma-andromedae
July 13th, 2011, 01:49 PM
Hi SunMade,

thanks for your suggestions.

For me, just blacklisting acer_wmi worked fine. No further problems with WLAN!

(Having to keep Win 7 just for that purpose is sad indeed. I decided to delete all NTFS partitions during the Ubuntu setup.)

Concerning suspend & hibernate, I do not want to disable but to *use* them. So, I'll try the modprobe hack first, later today.

Kind regards!

gamma-andromedae
July 14th, 2011, 09:42 AM
In order to fix the blank screen after resume problem, yesterday I wrote a new file 'i915-disable-ssc.conf' into /etc/modprobe.d containing the single line

options i915.lvds_use_ssc=0

and restarted. Unfortunately, this did NOT fix the resume problem for me.

Any ideas what might still be going wrong here, or what I am doing wrong!?

mp80
August 3rd, 2011, 11:01 PM
I found that following what was posted here (http://forums.linuxmint.com/viewtopic.php?f=49&t=75306) solved the problem - it's pretty much what you have already tried, but with a bit extra. In /etc/modprobe.d I created the file i915-disable-ssc.conf containing the line:

options i915 modeset=1 lvds_use_ssc=0

I then ran:

sudo update-initramfs -k all -u

and restarted. Now if I resume for a suspend the screen works as expected again - although it took a few seconds to return from black! I'm not sure if it's including "modeset=1", or running update-initramfs that helped over what you'd previously done, but hopefully this will work for you.