Difference between revisions of "Lenovo ThinkPad T420"

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[[Category:Lenovo]]
 
[[Category:Lenovo]]
 +
[[zh-CN:Lenovo ThinkPad T420]]
 +
{{Out of date|{{ic|rc.conf}} references}}
 
This article covers the installation and configuration of Arch Linux on a Lenovo T420 laptop.
 
This article covers the installation and configuration of Arch Linux on a Lenovo T420 laptop.
  
==Installation==
+
== Installation ==
This laptop supports [[Unified_Extensible_Firmware_Interface|UEFI]] as well as the traditional BIOS.
+
 
 +
This laptop supports [[UEFI]] as well as the traditional BIOS.
  
 
There are no issues with installing Arch Linux with the latest [https://www.archlinux.org/download/ Archiso].
 
There are no issues with installing Arch Linux with the latest [https://www.archlinux.org/download/ Archiso].
  
The rest of the installation process can be followed with the [[Official_Arch_Linux_Install_Guide|official install guide]].
+
The rest of the installation process can be followed with the [[Installation guide]].
 +
 
 +
== Hardware ==
  
==Hardware==
 
 
All hardware works out of the box except the following:
 
All hardware works out of the box except the following:
  
===Fingerprint reader===
+
=== Fingerprint reader ===
 +
 
 
Fingerprint reader works great with fprint and PAM (installation of fingerprint-gui recommended).
 
Fingerprint reader works great with fprint and PAM (installation of fingerprint-gui recommended).
  
See [[Fprint#Setup_fingerprint-gui]] for more information.
+
See [[Fprint#Setup fingerprint-gui]] for more information.
  
===Some Media Keys===
+
=== Some Media keys ===
* See [[Lenovo ThinkPad T420#Media Keys|below]]
+
 
 +
* See [[#Media Keys|Media Keys]]
 +
 
 +
=== Untested ===
  
===Untested===
 
 
* Firewire
 
* Firewire
  
 
==Laptop Settings==
 
==Laptop Settings==
 +
 
===ACPI===
 
===ACPI===
 +
 
[[ACPI_modules|ACPI]] is well supported here. No obvious troubleshoots.
 
[[ACPI_modules|ACPI]] is well supported here. No obvious troubleshoots.
  
 
=== Tp_smapi ===
 
=== Tp_smapi ===
Unfortunately, [[Tp_smapi|tp_smapi]] is only partially supported on the Thinkpad T420. A number of features work since version 0.41. For example, the hard drive protection mechanism [[HDAPS]] now works well. See the linked wiki entry.
 
  
Some features like setting the starting threshold for charging the battery do not yet work. To control the battery charging thresholds, install the Perl script {{AUR|tpacpi-bat}} from the [[Arch User Repository|AUR]].
+
Unfortunately, [[tp_smapi]] is only partially supported on the Thinkpad T420. A number of features work since version 0.41. For example, the hard drive protection mechanism [[HDAPS]] now works well. See the linked wiki entry.
 +
 
 +
Some features like setting the starting threshold for charging the battery do not yet work. To control the battery charging thresholds, install the Perl script {{AUR|tpacpi-bat}} from the [[AUR]].
  
 
Insert the {{ic|acpi_call}} kernel module by running
 
Insert the {{ic|acpi_call}} kernel module by running
 
  modprobe acpi_call
 
  modprobe acpi_call
or by adding it to the {{ic|MODULES}} array in {{ic|/etc/[[rc.conf]]}}.
 
  
 
Manually set the thresholds by calling
 
Manually set the thresholds by calling
  perl /usr/lib/perl5/vendor_perl/tpacpi-bat -v startChargeThreshold 0 40
+
  /usr/bin/perl /usr/bin/tpacpi-bat -v -s SP 0 80
  perl /usr/lib/perl5/vendor_perl/tpacpi-bat -v stopChargeThreshold 0 80
+
  /usr/bin/perl /usr/bin/tpacpi-bat -v -s ST 0 40
The example values 40 and 80 given here are in percent of the full battery capacity. Adjust them to your own needs. You may also want to add these lines to {{ic|/etc/rc.local}} to set them at startup. While these values should be permanent, they will be reset any time the battery is removed.
+
The example values 40 and 80 given here represent the percentage of full battery capacity remaining. Adjust them to your own needs. You may also want to write a simple {{ic|set-battery.service}} and enable it to set them at startup. While these values should be permanent, they will be reset any time the battery is removed.
 +
 
 +
[Unit]
 +
Description=Set battery capacity
 +
 +
[Service]
 +
Type=oneshot
 +
ExecStart=/usr/bin/perl /usr/bin/tpacpi-bat -v -s SP 0 80
 +
ExecStart=/usr/bin/perl /usr/bin/tpacpi-bat -v -s ST 0 40
 +
 +
[Install]
 +
WantedBy=multi-user.target
 +
  
 
Also, if you are dual booting with Windows, you can still control the battery charging thresholds with Lenovo's Power Manager which communicates directly to the battery controller.
 
Also, if you are dual booting with Windows, you can still control the battery charging thresholds with Lenovo's Power Manager which communicates directly to the battery controller.
Line 45: Line 66:
 
When using systemd, you may want to blacklist the tp_smapi module if your systemd-modules-load.service fails, as new ThinkPads handle everything over acpi.
 
When using systemd, you may want to blacklist the tp_smapi module if your systemd-modules-load.service fails, as new ThinkPads handle everything over acpi.
  
=== CPU Frequency Scaling ===
+
=== CPU frequency scaling ===
[[CPU Frequency Scaling|CPU frequency scaling]] is fully supported with all of the available processor models with this laptop.
+
 
 +
[[CPU frequency scaling]] is fully supported with all of the available processor models with this laptop.
  
 
=== Fans ===
 
=== Fans ===
  
The thinkpad_acpi kernel module needs to be configured so user space programs can control the fan speed.
+
Install the package {{AUR|thinkfan}}. It will automatically create the necessary acpi configuration file in {{ic|/usr/lib/modprobe.d/thinkpad_acpi.conf}}.
  
{{hc|/etc/modprobe.d/modprobe.conf|2=options thinkpad_acpi fan_control=1}}
+
Copy the example sensor settings file from "/usr/share/doc/thinkfan/examples/thinkfan.conf.simple" to "/etc/thinkfan.conf".
 +
{{bc|# cp /usr/share/doc/thinkfan/examples/thinkfan.conf.simple /etc/thinkfan.conf}}
  
The [https://aur.archlinux.org/packages.php?ID=24359 thinkfan] configuration file also needs to know how to set the fan speed. Replace the default sensor settings with the following.
+
Aftwards replace the default {{ic|hwmon}} in the settings file {{ic|/etc/thinkfan.conf}} with the following:
 +
{{hc|/etc/thinkfan.conf|hwmon /sys/devices/virtual/thermal/thermal_zone0/temp}}
  
{{hc|/etc/thinkfan.conf|sensor /sys/devices/virtual/thermal/thermal_zone0/temp}}
+
Alternatively, sensors can be generated using following command. Add {{ic|hwmon}} before the sensor lines.
 +
{{bc|find /sys/devices -type f -name "temp*_input"}}
  
You can add or remove services by editing the {{ic|DAEMONS}} array in your /etc/[[rc.conf]] file. It will initially look something like this:
+
In the same configuration file replace the default fan level settings with your needs (the last lines of the file). Useful values are
DAEMONS=(...@thinkfan...)
+
{{bc|(0, 0, 42)
 +
(1, 40, 47)
 +
(2, 45, 52)
 +
(3, 50, 57)
 +
(4, 55, 62)
 +
(5, 60, 67)
 +
(6, 65, 72)
 +
(7, 70, 77)
 +
(127, 75, 32767)}}
  
Or, if you are using systemd, simply type
+
Finally [[enable]] the '''thinkfan''' service.
# systemctl enable thinkfan.service
+
{{bc|# systemctl enable thinkfan}}
  
 
=== Laptop Mode Tools ===
 
=== Laptop Mode Tools ===
 +
 
No significant issues were found using [[Laptop Mode Tools]].
 
No significant issues were found using [[Laptop Mode Tools]].
  
Possible bug with [[Lenovo_ThinkPad_T420#Shutdown on Battery]]
+
Possible bug with [[#Shutdown on battery]].
  
{{AUR|tlp}} From the [[Arch User Repository|AUR]] is an alternative tool that can replace laptop-mode-tools.
+
The package {{Pkg|tlp}} is an alternative tool that can replace {{AUR|laptop-mode-tools}}.
  
=== PM-Utils ===
+
=== Synaptics ===
Suspending and hibernating with [[Pm-utils|pm-utils]] works as intended.
+
  
===Synaptics===
+
TouchPad and TrackPoint do work out of the box, but the TrackPoint is way too sensitive (i.e. fast) to be usable, since it is recognized as a mouse. Configure both devices as described in  [[Touchpad Synaptics]] and [[TrackPoint]].
TouchPad and TrackPoint do work out of the box, but the TouchPad is way too sensitive (i.e. fast) to be usable, since it is recognized as a mouse. To fix this, [[pacman|install]] the {{Pkg|xf86-input-synaptics}} package and add the following two files to your {{ic|/etc/X11/xorg.conf.d/}} directory:
+
  
{{hc|50-thinkpad-trackpoint.conf|<nowiki>
+
To adjust the speed/sensitivity of the TrackPoint add these lines in a systemd tmpfile:
Section "InputClass"
+
        Identifier      "ThinkPad TrackPoint"
+
        MatchProduct    "TPPS/2 IBM TrackPoint"
+
        MatchDevicePath "/dev/input/event*"
+
        Option          "EmulateWheel"          "true"
+
        Option          "EmulateWheelButton"    "2"
+
        Option          "XAxisMapping"          "6 7"
+
        Option          "YAxisMapping"          "4 5"
+
EndSection
+
</nowiki>}}
+
  
{{hc|50-twofingerscroll.conf|<nowiki>
+
{{hc|/etc/tmpfiles.d/local.conf|
Section "InputClass"
+
w /sys/devices/platform/i8042/serio1/speed - - - - 180
        Identifier      "two finger scrolling"
+
w /sys/devices/platform/i8042/serio1/sensitivity - - - - 200
        Driver          "synaptics"
+
}}
        MatchProduct    "SynPS/2 Synaptics TouchPad"
+
        MatchDevicePath "/dev/input/event*"
+
        Option          "VertTwoFingerScroll"  "on"
+
        Option          "HorizTwoFingerScroll"  "on"
+
        Option          "EmulateTwoFingerMinW"  "8"
+
        Option          "EmulateTwoFingerMinZ"  "40"
+
        Option          "TapButton1"            "1"
+
EndSection
+
</nowiki>}}
+
  
Adjust to your own needs. Read [[Touchpad Synaptics]] for more information.
+
Possible range of values are 1-255.
  
To adjust the speed/sensitivity of the TrackPoint add these lines in your {{ic|/etc/rc.local}} script:
+
Alternatively, you can add an [[udev]] rule:
  
{{hc|/etc/rc.local|<nowiki>
+
{{hc|/etc/udev/rules.d/10-trackpoint.rules|
TPDEV=/sys/devices/platform/i8042/serio1
+
<nowiki>ACTION=="add",DEVPATH=="/devices/platform/i8042/serio4/serio5",ATTR{sensitivity}="128",ATTR{speed}="200"</nowiki>
echo -n 180 > $TPDEV/speed
+
}}
echo -n 200 > $TPDEV/sensitivity
+
</nowiki>}}
+
  
Possible range of values are 1-255.
+
=== NVIDIA Optimus ===
  
===NVIDIA Optimus===
+
[[Bumblebee]] works as intended on models with NVIDIA Optimus
[[Bumblebee|Bumblebee]] works as intended on models with NVIDIA Optimus
+
  
 
=== Optional kernel boot arguments ===
 
=== Optional kernel boot arguments ===
 
Using the following kernel boot parameters [http://www.phoronix.com/scan.php?page=article&item=intel_i915_power&num=1| reduces battery drain]:
 
Using the following kernel boot parameters [http://www.phoronix.com/scan.php?page=article&item=intel_i915_power&num=1| reduces battery drain]:
 +
 
{{bc|<nowiki>
 
{{bc|<nowiki>
 
i915.i915_enable_rc6=1
 
i915.i915_enable_rc6=1
Line 127: Line 138:
 
</nowiki>}}
 
</nowiki>}}
  
{{Note| With the current 3.6.x kernels, there appears to be a power regression with an unknown cause. It is yet to be fixed in any 3.7 versions of the kernel.}}
+
== Troubleshooting ==
  
==Troubleshooting==
 
 
=== Media Keys ===
 
=== Media Keys ===
Media keys that work out of the box:
+
 
 +
Media keys that (should) work out of the box:
 
* Wireless On/Off
 
* Wireless On/Off
 
* Backlight Brightness settings
 
* Backlight Brightness settings
 
* Thinklight
 
* Thinklight
 
* Mute
 
* Mute
 +
* Microphone mute
  
 
Media Keys that Do Not work out of the box:
 
Media Keys that Do Not work out of the box:
* [[Lenovo_ThinkPad_T420#Volume_up.2Fdown_not_changing_volume|Volume keys]] (Works out-of-the-box in [[Gnome|Gnome]])
+
* [[#Volume_up.2Fdown_not_changing_volume|Volume keys]] (Works out-of-the-box in [[GNOME]])
* Microphone mute
+
 
You must find a workaround and bind the keys yourself for the rest of them.
 
You must find a workaround and bind the keys yourself for the rest of them.
 +
 +
[[xbindkeys]] and {{AUR|xbindkeys_config-gtk2}} can be a solution for media keys that are not working. This solution also allows you to rebind the ThinkVantage button and certain FN layer shortcuts (the blue logos on the keyboard).
  
 
=== Rebind Forward and Back keys ===
 
=== Rebind Forward and Back keys ===
 +
 
Keys forward and back (next to cursor keys) can be easily remapped to PageDown/PageUp.
 
Keys forward and back (next to cursor keys) can be easily remapped to PageDown/PageUp.
  
[[pacman|Install]] xmodmap with the package {{Pkg|xorg-server-utils}}
+
[[Install]] xmodmap with the package {{Pkg|xorg-server-utils}}
  
 
Create a {{ic|~/.Xmodmap}} file with content:
 
Create a {{ic|~/.Xmodmap}} file with content:
Line 154: Line 168:
 
  xmodmap ~/.Xmodmap
 
  xmodmap ~/.Xmodmap
  
You can also re-map AudioPrev ({{Keypress|Fn+Left}}) and AudioNext ({{Keypress|Fn+Right}}) to Home/End:
+
You can also re-map AudioPrev ({{ic|Fn+Left}}) and AudioNext ({{ic|Fn+Right}}) to Home/End:
 
  keysym XF86AudioNext = End
 
  keysym XF86AudioNext = End
 
  keysym XF86AudioPrev = Home
 
  keysym XF86AudioPrev = Home
  
{{Note|You have to log out for the changes to take effect.}}
+
{{Note|
 
+
* You have to log out for the changes to take effect.
{{Note|The keys should work out of the box, at least on [[KDE]].}}
+
* The keys should work out of the box, at least on [[KDE]].
 +
}}
  
 
=== Turn touchpad on and off ===
 
=== Turn touchpad on and off ===
For some, the ({{Keypress|Fn+F8}}) key does not switch the touchpad on and off. Here is a simple keybind to add to your {{ic|~/.xbindkeysrc}} for keys to quickly change your touchpad state. For these to take effect, run {{ic|xbindkeysrc}}. This binds {{Keypress|Fn+F8}} to 'toggle the touchpad on and off'. (Tested in i3wm and xfce4, where normal {{Keypress|Fn+F8}} does not toggle the touchpad)
 
  
# Toggle the Touchpad on|off
+
For some, the ({{ic|Fn+F8}}) key does not switch the touchpad on and off. See [[Touchpad Synaptics#Software toggle]] for a workaround.
"synclient TouchpadOff=`synclient -l | grep -ce TouchpadOff.*0`"
+
    m:0x0 + c:199
+
    XF86TouchpadToggle
+
  
 
=== Volume up/down not changing volume ===
 
=== Volume up/down not changing volume ===
Another quick keybind for {{ic|~/.xbindkeysrc}} to change the volume (which does not work on some DEs). Again, run {{ic|xbindkeys}} for these to take effect. Taken from [[Xbindkeys]]
 
 
#increase volume
 
"amixer set Master playback 1+"
 
    m:0x0 + c:123
 
    XF86AudioRaiseVolume
 
  
#decrase volume
+
See [[Xbindkeys]].
"amixer set Master playback 1-"
+
    m:0x0 + c:122
+
    XF86AudioLowerVolume
+
  
Also, while the mute button works, I rebound it to interface with ALSA.
+
=== Shutdown on battery ===
  
# Toggle mute
 
"amixer set Master toggle"
 
    m:0x0 + c:121
 
    XF86AudioMute
 
 
=== Shutdown on Battery ===
 
 
Some users have reported that the T420 was rebooting on shutdown on battery power. There have been quite a few attempts to fix this. Three are detailed here.  
 
Some users have reported that the T420 was rebooting on shutdown on battery power. There have been quite a few attempts to fix this. Three are detailed here.  
  
One way is to disable the module {{ic|ehci_hcd}}. See [[Kernel_modules#Blacklisting]] for more information.
+
One way is to disable the module {{ic|ehci_hcd}}. See [[Kernel modules#Blacklisting]] for more information.
  
 
Or try disable Laptop-mode.  
 
Or try disable Laptop-mode.  
Line 201: Line 197:
 
[https://bbs.archlinux.org/viewtopic.php?pid=1106437#p1106437 This forum post] details another way to have your computer not reboot on shutdown. Turning off the {{ic|laptop-mode}} daemon causes battery life to suffer, so when on the move and in need of a simple way to shutdown, this seems to work better.
 
[https://bbs.archlinux.org/viewtopic.php?pid=1106437#p1106437 This forum post] details another way to have your computer not reboot on shutdown. Turning off the {{ic|laptop-mode}} daemon causes battery life to suffer, so when on the move and in need of a simple way to shutdown, this seems to work better.
  
=== Hang on Reboot ===
+
=== Hang on reboot ===
This is a problem on many laptops and can be fixed by [[Kernel modules#Blacklisting|blacklisting]] the {{ic|e1000e}} kernel module.
+
  
=== No Backlight Controls ===
+
This is a problem on many laptops and can be fixed by [[blacklisting]] the {{ic|e1000e}} kernel module.
One user has reported that the brightness controls (fn+home, fn+end) did not work in some desktop environments. This could be fixed by adding the following kernel options:
+
acpi_backlight=vendor acpi_osi=Linux
+
  
 
== See also ==
 
== See also ==
 +
 
* [[Lenovo ThinkPad T420s]]
 
* [[Lenovo ThinkPad T420s]]
 
* [http://sysphere.org/~anrxc/j/articles/thinkpad-t420/index.html Arch Linux on ThinkPad T420i]
 
* [http://sysphere.org/~anrxc/j/articles/thinkpad-t420/index.html Arch Linux on ThinkPad T420i]

Latest revision as of 16:14, 13 May 2016

Tango-view-refresh-red.pngThis article or section is out of date.Tango-view-refresh-red.png

Reason: rc.conf references (Discuss in Talk:Lenovo ThinkPad T420#)

This article covers the installation and configuration of Arch Linux on a Lenovo T420 laptop.

Installation

This laptop supports UEFI as well as the traditional BIOS.

There are no issues with installing Arch Linux with the latest Archiso.

The rest of the installation process can be followed with the Installation guide.

Hardware

All hardware works out of the box except the following:

Fingerprint reader

Fingerprint reader works great with fprint and PAM (installation of fingerprint-gui recommended).

See Fprint#Setup fingerprint-gui for more information.

Some Media keys

Untested

  • Firewire

Laptop Settings

ACPI

ACPI is well supported here. No obvious troubleshoots.

Tp_smapi

Unfortunately, tp_smapi is only partially supported on the Thinkpad T420. A number of features work since version 0.41. For example, the hard drive protection mechanism HDAPS now works well. See the linked wiki entry.

Some features like setting the starting threshold for charging the battery do not yet work. To control the battery charging thresholds, install the Perl script tpacpi-batAUR from the AUR.

Insert the acpi_call kernel module by running

modprobe acpi_call

Manually set the thresholds by calling

/usr/bin/perl /usr/bin/tpacpi-bat -v -s SP 0 80 
/usr/bin/perl /usr/bin/tpacpi-bat -v -s ST 0 40

The example values 40 and 80 given here represent the percentage of full battery capacity remaining. Adjust them to your own needs. You may also want to write a simple set-battery.service and enable it to set them at startup. While these values should be permanent, they will be reset any time the battery is removed.

[Unit]
Description=Set battery capacity

[Service]
Type=oneshot
ExecStart=/usr/bin/perl /usr/bin/tpacpi-bat -v -s SP 0 80
ExecStart=/usr/bin/perl /usr/bin/tpacpi-bat -v -s ST 0 40

[Install]
WantedBy=multi-user.target

Also, if you are dual booting with Windows, you can still control the battery charging thresholds with Lenovo's Power Manager which communicates directly to the battery controller.

When using systemd, you may want to blacklist the tp_smapi module if your systemd-modules-load.service fails, as new ThinkPads handle everything over acpi.

CPU frequency scaling

CPU frequency scaling is fully supported with all of the available processor models with this laptop.

Fans

Install the package thinkfanAUR. It will automatically create the necessary acpi configuration file in /usr/lib/modprobe.d/thinkpad_acpi.conf.

Copy the example sensor settings file from "/usr/share/doc/thinkfan/examples/thinkfan.conf.simple" to "/etc/thinkfan.conf".

# cp /usr/share/doc/thinkfan/examples/thinkfan.conf.simple /etc/thinkfan.conf

Aftwards replace the default hwmon in the settings file /etc/thinkfan.conf with the following:

/etc/thinkfan.conf
hwmon /sys/devices/virtual/thermal/thermal_zone0/temp

Alternatively, sensors can be generated using following command. Add hwmon before the sensor lines.

find /sys/devices -type f -name "temp*_input"

In the same configuration file replace the default fan level settings with your needs (the last lines of the file). Useful values are

(0,	0,	42)
(1,	40,	47)
(2,	45,	52)
(3,	50,	57)
(4,	55,	62)
(5,	60,	67)
(6,	65,	72)
(7,	70,	77)
(127,	75,	32767)

Finally enable the thinkfan service.

# systemctl enable thinkfan

Laptop Mode Tools

No significant issues were found using Laptop Mode Tools.

Possible bug with #Shutdown on battery.

The package tlp is an alternative tool that can replace laptop-mode-toolsAUR.

Synaptics

TouchPad and TrackPoint do work out of the box, but the TrackPoint is way too sensitive (i.e. fast) to be usable, since it is recognized as a mouse. Configure both devices as described in Touchpad Synaptics and TrackPoint.

To adjust the speed/sensitivity of the TrackPoint add these lines in a systemd tmpfile:

/etc/tmpfiles.d/local.conf
w /sys/devices/platform/i8042/serio1/speed - - - - 180
w /sys/devices/platform/i8042/serio1/sensitivity - - - - 200

Possible range of values are 1-255.

Alternatively, you can add an udev rule:

/etc/udev/rules.d/10-trackpoint.rules
ACTION=="add",DEVPATH=="/devices/platform/i8042/serio4/serio5",ATTR{sensitivity}="128",ATTR{speed}="200"

NVIDIA Optimus

Bumblebee works as intended on models with NVIDIA Optimus

Optional kernel boot arguments

Using the following kernel boot parameters reduces battery drain:

i915.i915_enable_rc6=1
i915.i915_enable_fbc=1
i915.lvds_downclock=1 
i915.semaphores=1

Troubleshooting

Media Keys

Media keys that (should) work out of the box:

  • Wireless On/Off
  • Backlight Brightness settings
  • Thinklight
  • Mute
  • Microphone mute

Media Keys that Do Not work out of the box:

You must find a workaround and bind the keys yourself for the rest of them.

xbindkeys and xbindkeys_config-gtk2AUR can be a solution for media keys that are not working. This solution also allows you to rebind the ThinkVantage button and certain FN layer shortcuts (the blue logos on the keyboard).

Rebind Forward and Back keys

Keys forward and back (next to cursor keys) can be easily remapped to PageDown/PageUp.

Install xmodmap with the package xorg-server-utils

Create a ~/.Xmodmap file with content:

keysym XF86Back = Page_Up
keysym XF86Forward = Page_Down

Add this line to your ~/.xinitrc to make it work:

xmodmap ~/.Xmodmap

You can also re-map AudioPrev (Fn+Left) and AudioNext (Fn+Right) to Home/End:

keysym XF86AudioNext = End
keysym XF86AudioPrev = Home
Note:
  • You have to log out for the changes to take effect.
  • The keys should work out of the box, at least on KDE.

Turn touchpad on and off

For some, the (Fn+F8) key does not switch the touchpad on and off. See Touchpad Synaptics#Software toggle for a workaround.

Volume up/down not changing volume

See Xbindkeys.

Shutdown on battery

Some users have reported that the T420 was rebooting on shutdown on battery power. There have been quite a few attempts to fix this. Three are detailed here.

One way is to disable the module ehci_hcd. See Kernel modules#Blacklisting for more information.

Or try disable Laptop-mode. Add !laptop-mode to the DAEMONS array in /etc/rc.conf:

DAEMONS=(...!laptop-mode...)

This forum post details another way to have your computer not reboot on shutdown. Turning off the laptop-mode daemon causes battery life to suffer, so when on the move and in need of a simple way to shutdown, this seems to work better.

Hang on reboot

This is a problem on many laptops and can be fixed by blacklisting the e1000e kernel module.

See also