Touchpad Synaptics

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synaptics is a driver for the Synaptics TouchPad which is manufactured in most laptops. This article will help install and configure the driver according to your needs.


For Xorg 7.3 users

You can install the synaptics modules via pacman from the extra repository:

# pacman -S synaptics

Edit /etc/X11/xorg.conf as root and add InputDevice "Touchpad" "SendCoreEvents" to the ServerLayout:

Section "ServerLayout"
	InputDevice    "USB Mouse" "CorePointer"
	InputDevice    "Touchpad"  "SendCoreEvents"

Add Load "synaptics" to the Module section, for example:

Section "Module"
	Load  "freetype"
	Load  "record"
	Load "synaptics"

Lastly, add a new InputDevice section for the touchpad itself:

Section "InputDevice"
	Identifier      "Touchpad"
       Driver          "synaptics"
       Option  "Device"        "/dev/input/mouse0"
	Option  "Protocol"      "auto-dev"
	Option  "LeftEdge"      "1700"
	Option  "RightEdge"     "5300"
	Option  "TopEdge"       "1700"
	Option  "BottomEdge"    "4200"
	Option  "FingerLow"     "25"
	Option  "FingerHigh"    "30"
	Option  "MaxTapTime"    "180"
	Option  "MaxTapMove"    "220"
	Option  "VertScrollDelta" "100"
	Option  "MinSpeed"      "0.06"
	Option  "MaxSpeed"      "0.12"
	Option  "AccelFactor" "0.0010"
	Option  "SHMConfig"     "on"

For ALPS touchpads: If the above configuration isn't working for you, try the following configuration instead:

Section "InputDevice"
       Identifier  "Touchpad"
	Driver  "synaptics"
	Option  "Device"   "/dev/input/mouse0"
	Option  "Protocol"   "auto-dev"
	Option  "LeftEdge"   "130"
	Option  "RightEdge"   "840"
	Option  "TopEdge"   "130"
	Option  "BottomEdge"   "640"
	Option  "FingerLow"   "7"
	Option  "FingerHigh"   "8"
	Option  "MaxTapTime"   "180"
	Option  "MaxTapMove"   "110"
	Option  "EmulateMidButtonTime"   "75"
	Option  "VertScrollDelta"   "20"
	Option  "HorizScrollDelta"   "20"
	Option  "MinSpeed"   "0.25"
	Option  "MaxSpeed"   "0.50"
	Option  "AccelFactor"   "0.010"
	Option  "EdgeMotionMinSpeed"   "200"
	Option  "EdgeMotionMaxSpeed"   "200"
	Option  "UpDownScrolling"   "1"
	Option  "CircularScrolling"   "1"
	Option  "CircScrollDelta"   "0.1"
	Option  "CircScrollTrigger"   "2"
	Option  "SHMConfig"   "on"
	Option  "Emulate3Buttons"   "on"

Save, exit and restart X. The touchpad should now have working scroll zones. You can further tweak the InputDevice settings if desired. See Advanced Configuration for more information.

Note that your newly modified Xorg config will automatically load the evdev and psmouse kernel modules required by synaptics, however if desired you may add them explicitly to the MODULES array in the /etc/rc.conf file:

MODULES=( ... evdev psmouse ... )

For Xorg 7.4 users

You must have already enabled testing repository, so just :

# pacman -S xf86-input-synaptics

Mostly, when next time you entering X, you'll find your Touchpad works without any configure. Infact in Xorg 7.4, you even don't need a xorg.conf to get X work. But if not or you want some changes of default settings, you can modify xorg.conf just like above.

Configurations using GUI applications


Once the synaptics driver has been installed, GNOME users can also install the gsynaptics package to enable a GUI-based control panel:

# pacman -S gsynaptics

To save and load the settings from gsynaptics automatically, add gsynaptics-init to the list of Startup Programs found in System -> Preferences -> Sessions.

Note: Non-GNOME users can also use gsynaptics by instead adding gsynaptics-init to their .xinitrc or .xsession startup scripts.

Advanced Configuration

The synaptics driver offers a number of options that can be customized. The following list describes the InputDevice options we declared in the Xorg config:

Identifier is the name of this input device you've specified in the server layout section above.

Device defines where your synaptic device is located. See Troubleshooting to find your device handler if it isn't /dev/input/mouse0 for you.

LeftEdge, RightEdge, TopEdge and BottomEdge are integer values which indicate the dimensions of your touchpad as x or y coordinates.

FingerLow and FingerHigh are integer values which indicate the 'pressure value' at which the driver counts a touch (pressure value goes above FingerHigh) or a release (pressure value drops below FingerLow).

MaxTapTime is an integer value that defines the maximum time for detecting a tap (in milliseconds).

MaxTapMove is an integer value which defines the maximum movement of your finger for detecting a tap.

MinSpeed and MaxSpeed are set to determine the minimum and maximum speed factor. An floating point value is expected. VertScrollDelta

AccelFactor is the acceleration factor as well defined as a floating point value.

VertScrollDelta and HorizScrollDelta is an integer value defining scrolling speed. Smaller values result in faster scrolling.

SHMConfig is a boolean value (on/off) for activating or deactivating shared memory. This needs to be enabled if you want to monitor or configure your synaptics device with clients as synclient, which will be using in this article. Shared memory is also required if you want to use Udev rules to disable the touchpad automatically when external mouse is plugged in (see the relevant section below).

More options are explained in the synaptics' manpage, accessible with:

man 5 synaptics

Fine tuning with synclient

The synclient monitor can display pressure and placement on the touchpad in real-time, allowing further refinement of the default synaptics settings. In order for synclient to work properly, the SHMConfig option must be set to on or true.

You can start the synaptics monitor with the following command:

$ synclient -m 100

Where -m activates the monitor and the following number specifies the update interval in milliseconds.

This monitor provides information about the current state of your touchpad. For example, if you move the mouse with the touchpad, the x and y values in the monitor will change. Therewith you can easy figure out your touchpad's dimension which is defined in the LeftEdge-, RightEdge-, BottomEdge- and TopEdge-Options.

The abbreviations are explained as following:


Time in seconds since the logging was started.

x, y

The x/y coordinates of the finger on the touchpad. The origin is in the upper left corner.


The pressure value. It represents the pressure you are using to navigate on your touchpad.


Number of fingers currently touching the touchpad.


Value that represents the finger width.


Those values represent the state of the left, right, up, down, middle and multi buttons pressed where zero means not pressed and one means pressed.


For touchpads which have a guest device, this are the associated button states for guest left, guest middle and guest right pressed (1) and not pressed (0).

gdx, gdy

x/y coordinates of the guest device.

If a value constantly is zero, it means that this option is not supported by your device.

With this in mind you should be able to figure the proper values out for you.

Enable scrolling

Xorg 7.3 will enable Edge scrolling while Xorg 7.4 enable Two Fingers scrolling by default. So if you don't like it, just do as followed.

Edge scrolling

Normal scrolling, when dragging along the edges, enable scrolling. just add the following options to device section:

Section "InputDevice"
      Option "VertEdgeScroll" "boolean"         #vertical scrolling when dragging along the right edge.
      Option "HorizEdgeScroll" "boolean"        #horizontal scrolling when dragging along the bottom edge.

Circular scrolling

Circular scrolling is a feature that synaptics offers which you probably know from the iPod. Instead of (or additional to) scrolling horizontally or vertically, you can scroll circularly. Some users find this faster and more precise. To enable circular scrolling, you have to add the following options to your input device section as defined above:

Section "InputDevice"
        Option      "CircularScrolling"          "on"
        Option      "CircScrollTrigger"          "0"

As you've might guessed CircularScrolling enables or disables circular scrolling. The option CircScrollTrigger may be one of the following values, determining on which edge circular scrolling should start:

0    All Edges
1    Top Edge
2    Top Right Corner
3    Right Edge
4    Bottom Right Corner
5    Bottom Edge
6    Bottom Left Corner
7    Left Edge
8    Top Left Corner

Specifying something different from zero may be useful if you want to use circular scrolling in conjunction with horizontal and / or vertical scrolling. If you do so, the type of scrolling is determined by the edge you're starting.

To scroll fast, draw small circles in the center of your touchpad. To scroll slow and more precise, draw large circles.

Two Fingers scrolling

Recent synaptics touchpads support two fingers scrolling: instead of just scrolling on the side of your touchpad you can also scroll using two fingers together. You might have seen this on Macbooks which uses this approach as default on Mac OSX.

Given that your hardware support this feature (there is not an easy way to discover, just give it a try) you can enable it by inserting this two lines into your synaptic InputDevice section:

Option   "VertTwoFingerScroll"   "1"
Option   "HorizTwoFingerScroll"  "1"

You will get a two finger enabled touchpad which supports top-bottom and left-right scrolling as well as regular lateral scrolling (if you have started from the configuration proposed above in this page)

NOTE for Firefox Users: You might find the default behaviour of Firefox pretty annoying relating to the horizontal scrolling. Just see Firefox and special touchpad events below to find out how to disable it.

Disabling touchpad on plugged in mouse

In assistance to udev, it is possible to automatically disable the touchpad if an external mouse has been plugged in.

To achieve this, you just have to add the following udev rule:

ACTION=="add", SUBSYSTEM=="input", ID_CLASS="mouse", RUN+="/usr/bin/synclient TouchpadOff=1"
ACTION=="remove", SUBSYSTEM=="input", ID_CLASS="mouse", RUN+="/usr/bin/synclient TouchpadOff=0"

Place this into /etc/udev/rules.d/01-touchpad.rules and make sure SharedMemory has been enabled and you should be fine.

Other features

By default, Synaptics touchpads are able to detect the number of fingers on the touchpad, ALPS touchpads are not. If the touchpad is tapped with two fingers, it will emulate a middle click. If the touchpad is typed with three fingers, a right click will be emulated.


My touchpad device isn't located at /dev/input/mouse0

If that's the case, you can use this command to display information about your all input devices:

cat /proc/bus/input/devices

Search for an input device which has the name "SynPS/2 Synaptics TouchPad". The Handler in this section will tell you which Device you have to specify in your xorg.conf.

Example output:

I: Bus=0011 Vendor=0002 Product=0007 Version=0000
N: Name="SynPS/2 Synaptics TouchPad"
P: Phys=isa0060/serio4/input0
S: Sysfs=/class/input/input1
H: Handlers=mouse0 event1 
B: EV=b
B: KEY=6420 0 7000f 0

As your Handlers are mouse0 and event1, you use /dev/input/mouse0.

Stopping the mouse from clicking while typing

This is a neat little trick incorporated with the synaptics driver, you can actually make sure that the touchpad is disabled while typing. It is a very simple procedure, so here is how it is done.

Just add the following line to your .xinitrc before you run your window manager:

syndaemon -i 2 &

The -i 2 switch sets the idle time to 2 seconds. The idle time specifies how many seconds to wait after the last key press before enabling the touchpad again.

Additionally you can add the -t switch that tells the daemon not to disable mouse movement when typing and only disable tapping and scrolling:

syndaemon -t -i 2 &

As usual you may find further information in the manpage:

$ man syndaemon

Firefox and special touchpad events

Even though this problem isn't concerning the synaptics drivers, you will probably look up here for a solution anyway. By default firefox is set up to do special events on tapping or scrolling certain parts of your touchpad. You can edit the settings of those actions by typing about:config in your firefox adress bar. Editing takes place by double clicking on those lines, true changes to false and vise versa, a numerical value you'll have to change manually.

To prevent firefox from scrolling (back and forward) through the history and make it scroll the site, you have to edit the following settings:

mousewheel.horizscroll.withnokey.action = 1
mousewheel.horizscroll.withnokey.sysnumlines = true

To prevent firefox from redirecting you to urls formed out of your clipboard content, on tapping the upper-rigt corner of your touchpad (or middle mouse button), you have to set the following line to false:

middlemouse.contentLoadURL = false

Opera misinterprets horizontal scrolling

Same as above. To fix it, go to Tools -> Preferences -> Advanced -> Shortcuts. There you edit the mouse preferences: Delete the entries with "Button 5" and "Button 6".

Scrolling and multiple actions with synaptics on LG Laptops

These problems seems to be occuring on several models of LG laptops. Symptoms are that when pressing Mouse Button 1 synaptics interpretes it as ScrollUP and a regular button 1 click, same goes for button 2.

The scrolling can be solved by entering in xorg.conf:

Option "UpDownScrolling" "0"

This however will make synaptics interprete one button push as three. There is a patch written by Oskar Sandberg, found at , that removes these clicks.

However when trying to compile this with the latest version of synaptics it fails. The solution to this is using the GIT repository for synaptics. It can be found at .

There is also a package build file in the archlinux user repository to automate this,

Instructions on how to build this package, after downloading the tarball and unpacking it:

cd synaptics-git

If you want it to be automatically installed after it has build just add '-i' after makepkg.

Still can't get your USB (external) mouse working?

First, make sure your section describing the external mouse contains this line (or that the line looks like this):

Option	    "Device" "/dev/input/mice"

If the "Device" line is different, change it to the above, and try to restart X. If this doesn't solve your problem, make your touchpad the CorePointer in the "Server Layout" section:

InputDevice    "Touchpad" "CorePointer"

and make your external device "SendCoreEvents":

InputDevice    "USB Mouse" "SendCoreEvents"

finally add this to your external device's section:

Option      "SendCoreEvents"    "true"

If all of the above doesn't work for you, please check relevant bug trackers for possible bugs, or go through the forums to see if anyone has found a better solution.

Touchpad loses synchronization

Sometimes the cursor may freeze for several seconds or start acting on its own for no apparent reason. This is accompanied by similar records in /var/log/messages.log

 psmouse.c: TouchPad at isa0060/serio1/input0 lost synchronization, throwing 3 bytes away

This problem has no general solution, but you may try several possible workarounds.

  • If you use cpu frequency scaling, try not using "ondemand" governor and use "performance" governor when possible, since touchpad may lose sync when cpu frequency changes.
  • Try not using acpi battery monitor.
  • Try to load psmouse with "proto=imps" option. To do that, add this line to your /etc/modprobe.conf
options psmouse proto=imps
  • Try another desktop environment. Some users report, that this problem only occurs when using Xfce or Gnome and newer occurs under KDE.
  • If your touchpad loses sync not only under Linux, but under Windows too, this may be a hardware issue. So, you may need to replace the touchpad itself.

My toutchpad don't have tapping function

Xorg7.4 didn't allow tap by default, if you want this, simply add following to touchpad section:

Section "InputDevice"
        Option "TapButton1" "integer"
        Option "TapButton2" "integer"
        Option "TapButton3" "integer"

The interger of option "TapButton1" means which mouse button is reported on a non-corner one-finger tap. Usualy it is 1. The interger of option "TapButton2" means which mouse button is reported on a non-corner two-finger tap. Usualy it is 2. The interger of option "TapButton3" means which mouse button is reported on a non-corner three-finger tap. Usualy it is 3.

SynPS/2 Synaptics TouchPad can't grab event device, errno=16

if you are using Xorg7.4, you may get a warning like this from /var/log/Xorg.0.log, that's because the driver will grab the event device for exclusive use when using the linux 2.6 event protocol.

Grabbing the event device means that no other user space or kernel space program sees the touchpad events. This is desirable if the X config file includes /dev/input/mice as an input device, but is undesirable if you want to monitor the device from user space.

if you want to control it, add or modify the "GrabEventDevice" option in you touchpad section in xorg.conf:

Option "GrabEventDevice" "boolean"

That will efect when next time you start X, and you can also change it by using synclient. When changing this parameter with the synclient program, the change will not take effect until the synaptics driver is disabled and reenabled. This can be achieved by switching to a text console and then switching back to X.


Synaptics TouchPad driver for XOrg/XFree86 : [1]