Difference between revisions of "Touchpad Synaptics"

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This article details the installation and configuration process of the Synaptics input driver for Synaptics (and ALPS) touchpads found on most notebooks.

Installation

The Synaptics driver can be installed with the package xf86-input-synaptics, available in the official repositories.

Configuration

The primary method of configuration for the touchpad is through an Xorg server configuration file. After installation of xf86-input-synaptics, a default configuration file is located at /etc/X11/xorg.conf.d/50-synaptics.conf.

Users can edit this file to configure the various driver options available, for a complete list of all available options users should refer to the synaptics manual page:

$ man synaptics

Note: Synaptics 1.0 and higher support input device properties if the driver is running on X server 1.6 or higher. On these driver versions, Option "SHMConfig" is not needed to enable run-time configuration. See man page for more info.

Frequently used options

The following lists options that many users may wish to configure. Note that all these options can simply be added to the main configuration file in /etc/X11/xorg.conf.d/50-synaptics.conf, as shown in this example configuration file where we have enabled vertical, horizontal and circular scrolling:

/etc/X11/xorg.conf.d/50-synaptics.conf

 Section "InputClass"
       Identifier "touchpad"
       Driver "synaptics"
       MatchIsTouchpad "on"
              Option "TapButton1" "1"
              Option "TapButton2" "2"
              Option "TapButton3" "3"
              Option "VertEdgeScroll" "on"
              Option "VertTwoFingerScroll" "on"
              Option "HorizEdgeScroll" "on"
              Option "HorizTwoFingerScroll" "on"
              Option "CircularScrolling" "on"
              Option "CircScrollTrigger" "2"
              Option "EmulateTwoFingerMinZ" "40"
              Option "EmulateTwoFingerMinW" "8"
              Option "CoastingSpeed" "0"
              ...
 EndSection

TapButton1: (integer) configures which mouse-button is reported on a non-corner, one finger tap.
TapButton2: (integer) configures which mouse-button is reported on a non-corner, two finger tap
TapButton3: (integer) configures which mouse-button is reported on a non-corner, three finger tap
RBCornerButton: (integer) configures which mouse-button is reported on a right bottom corner, one finger tap (use Option "RBCornerButton" "3" to achieve Ubuntu style tap behaviour for right mouse button in lower right corner)
RTCornerButton: (integer) as above, but for top right corner, one finger tap.
VertEdgeScroll: (boolean) enables vertical scrolling while dragging across the right edge of the touch pad.
HorizEdgeScroll: (boolean) enables horizontal scrolling while dragging across the bottom edge of the touch pad.
VertTwoFingerScroll: (boolean) enables vertical scrolling using two fingers.
HorizTwoFingerScroll: (boolean) enables horizontal scrolling using two fingers.
EmulateTwoFingerMinZ/W: (integer) play with this value to set the precision of two finger scroll.

An example with a brief description of all options. As usual settings will vary between machines. It is recommended that you discover your own options using synclient.

Note: If you find that your hand frequently brushes your touchpad, causing the TapButton2 option to be triggered (which will more than likely paste from your clipboard), and you do not mind losing two-finger-tap functionality, set TapButton2 to -1.

Note: Recent versions include a "Coasting" feature, enabled by default, which may have the undesired effect of continuing almost any scrolling until the next tap or click, even if you are no longer touching the touchpad. This means that to scroll just a bit, you need to scroll (by using the edge, or a multitouch option) and then almost immediately tap the touchpad, otherwise scrolling will continue forever. If wish to avoid this, set CoastingSpeed to 0.

Other options

VertScrollDelta and HorizScrollDelta: (integer) configures the speed of scrolling, it's a bit counter-intuitive because higher values produce greater precision and thus slower scrolling. Negative values cause natural scrolling like in OS X.

SHMConfig: (boolean) Switch on/off shared memory for run-time debugging. This option does not have an effect on run-time configuration anymore and is only useful for hardware event debugging.

GNOME

Users of GNOME may have to edit its configuration as well, because in default it is set to disable tapping to click, horizontal scrolling and not to allow touchpad disabling while typing.

To change these settings in Gnome 2:

Run gconf-editor
Edit the keys in the /desktop/gnome/peripherals/touchpad/ folder.

To change these settings in Gnome 3:

Open System Settings.
Click Mouse and Touchpad.
Change the settings on the Touchpad tab.

Gnome settings daemon may override existing settings (for example ones set in xorg.conf.d) for which there is no equivalent in any of the graphical configuration utilities. It is possible to stop gnome from touching mouse settings at all:

Run dconf-editor
Edit /org/gnome/settings-daemon/plugins/mouse/
Uncheck the active setting

It will now respect your system's existing synaptics configuration.

MATE

As with GNOME, it is possible configure the way MATE handles the touchpad:

Run mateconf-editor
Edit the keys in the desktop/mate/peripherals/touchpad/ folder.

To prevent Mate settings daemon from overriding existing settings, do as follows:

Run mateconf-editor
Edit /apps/mate_settings_daemon/plugins/mouse/
Uncheck the active setting.

Configuration on the fly

Next to the traditional method of configuration, the Synaptics driver also supports on the fly configuration. This means that users can set certain options through a software application, these options are applied immediately without needing a restart of Xorg. This is useful to test configuration options before you include them in the configuration file.

Note: The SHMConfig option has been removed from Synaptics. Configuration through synclient doesn't need it anymore.

Warning: On-the-fly configuration is non-permanent and will not remain active through a reboot, suspend/resume, or restart of Xorg. This should only be used to test, fine-tune or script configuration features.

Console tools

Synclient (Recommended) — command line utility to configure and query Synaptics driver settings on a live system, the tool is developed by the synaptics driver maintainers and is provided with the synaptics driver

http://xorg.freedesktop.org/ || xf86-input-synaptics

xinput — small general-purpose CLI tool to configure devices

http://xorg.freedesktop.org/ || xorg-xinput

Graphical tools

Warning: Some of the tools below still require the obsolete SHMConfig mode, and will not work with current xf86-input-synaptics driver. Please remove outdated tools from the list.

GPointing Device Settings — provides graphical on the fly configuration for several pointing devices connected to the system, including your synaptics touch pad. This application replaces GSynaptics as the preferred tool for graphical touchpad configuration through the synaptics driver

http://live.gnome.org/GPointingDeviceSettings || gpointing-device-settings^AUR

Note: For GPointingDeviceSettings to work with Synaptics touchpads both xf86-input-synaptics and libsynaptics have to be installed!

GSynaptics (Deprecated!) — allows the user to configure options such as horizontal, vertical and circular scrolling as well as the option to enable or disable the touchpad. The GSynaptics website mentions that its development has stopped and that it will eventually be outdated, the application functions perfectly with xorg 1.11, through users looking for a graphical tools are suggested to use GPointingDeviceSettings instead, GSynaptics should only be used as a last resort

http://gsynaptics.sourceforge.jp/ || gsynaptics

Synaptiks — touchpad configuration and management tool for KDE. It provides a System Settings module to configure basic and advanced features of the touchpad. Additionally it comes with a little system tray application, which can switch the touchpad automatically off, while an external mouse is plugged or while you are typing.

http://synaptiks.lunaryorn.de || synaptiks

Advanced Configuration

Using xinput to determine touchpad capabilities

Depending on your model, synaptic touchpads may have or lack capabilities. We can determine which capabilities your hardware supports by using xinput.

left, middle and right hardware buttons
two finger detection
three finger detection
configurable resolution

First, find the name of your touchpad:

$ xinput -list

You can now use xinput to find your touchpad's capabilities:

$ xinput list-props "SynPS/2 Synaptics TouchPad" | grep Capabilities

      Synaptics Capabillities (309):  1, 0, 1, 0, 0, 1, 1

From left to right, this shows:

(1) device has a physical left button
(0) device does not have a physical middle button
(1) device has a physical right button
(0) device does not support two-finger detection
(0) device does not support three-finger detection
(1) device can configure vertical resolution
(1) device can configure horizontal resolution

Use xinput list-props "SynPS/2 Synaptics TouchPad" to list all device properties.

Synclient

Synclient can configure every option available to the user as documented in $ man synaptics. A full list of the current user settings can be brought up:

$ synclient -l

Every listed configuration option can be controlled through synclient, for example:

$ synclient PalmDetect=1 (to enable palm detection)
$ synclient TapButton1=1 (configure button events)
$ synclient TouchpadOff=1 (disable the touchpad)

After you have successfully tried and tested your options through synclient, you can make these changes permanent by adding them to /etc/X11/xorg.conf.d/50-synaptics.conf.

evtest

The tool evtest can display pressure and placement on the touchpad in real-time, allowing further refinement of the default Synaptics settings. The evtest monitoring can be started with:

$ evtest /dev/input/eventX

'X' denotes the touchpad's ID. It can be found by looking at the output of $ cat /proc/bus/input/devices.

evtest needs exclusive access to the device which means it cannot be run together with an X server instance. You can either kill the X server or run evtest from a different virtual terminal (e.g., by pressing Ctrl+Alt+2).

Circular Scrolling

Circular scrolling is a feature that Synaptics offers which closely resembles the behaviour of iPods. 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, add the following options to the touchpad device section of /etc/X11/xorg.conf.d/50-synaptics.conf:

/etc/X11/xorg.conf.d/50-synaptics.conf

 Section "InputClass"
         ...
         Option      "CircularScrolling"          "on"
         Option      "CircScrollTrigger"          "0"
         ...
 EndSection

The option CircScrollTrigger may be one of the following values, determining 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 start from.

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

Natural Scrolling

It is possible to enable natural scrolling through synaptics. Simply use negative values for VertScrollDelta and HorizScrollDelta like so:

/etc/X11/xorg.conf.d/50-synaptics.conf

 Section "InputClass"
         ...
         Option      "VertScrollDelta"          "-111"
         Option      "HorizScrollDelta"         "-111"
         ...
 EndSection

Software Toggle

You may find it useful to have a software toggle that will turn on or off your touchpad, especially if it is extremely sensitive and you are doing a lot of typing. Please also see #Disable touchpad upon external mouse detection as that may be better solution, a matter of choice. The advantage here is you have the control, while the other solution has a daemon determine when to turn off the trackpad.

You will want to grab xbindkeys if you do not already have key binding software.

Then save this script to something such as /usr/bin/trackpad-toggle.sh:

/usr/bin/trackpad-toggle.sh

 #!/bin/bash
 
 synclient TouchpadOff=$(synclient -l | grep -c 'TouchpadOff.*=.*0')

Then finally add a key binding to use the script. It is best to call with xbindkeys like so (file ~/.xbindkeysrc):

~/.xbindkeysrc

 "/usr/bin/trackpad-toggle.sh"
     m:0x5 + c:65
     Control+Shift + space

Now just (re)start xbindkeys and Template:Keypress+Template:Keypress+Template:Keypress will now toggle your trackpad!

Of course you could easily use any other keybinding software, such as the ones provided by Xfce4 and GNOME.

Disable Trackpad while Typing

Using automatic palm detection

First of all you should test if it works properly for your trackpad and if the settings are accurate:

$ synclient PalmDetect=1

Then test the typing. You can tweak the detection with:

$ synclient PalmMinWidth=

which is the width of the area your hand touches, and

$ synclient PalmMinZ=

which is the minimum Z distance at which the detection is performed.

Once you have found the correct settings, save them into /etc/X11/xorg.conf.d/50-synaptics.conf like this:

#synclient PalmDetect=1
Option "PalmDetect" "1"
#synclient PalmMinWidth=10
Option "PalmMinWidth" "10"
#synclient PalmMinZ=200
Option "PalmMinZ" "200"

Using .xinitrc

To have the touchpad disabled automatically when you begin typing, add the following line to your ~/.xinitrc before you run your window manager (if not using a login manager):

$ syndaemon -t -k -i 2 -d &

-i 2: 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.
-t: tells the daemon not to disable mouse movement when typing and only disable tapping and scrolling.
-k: tells the daemon to ignore modifier keys when monitoring keyboard activity (e.g.: allows Ctrl+Left Click).
-d: starts as a daemon, in the background.

More details are available in the man page:

$ man syndaemon

If you are using a login manager, you will need to specify the command where your DE allows you to do so.

Using a Login Manager

The "-d" option is necessary to start syndaemon as a background process for post Login instructions.

For GNOME: (GDM)

To start syndaemon you need to use Gnome's Startup Applications Preferences program. Login to Gnome and go to System > Preferences > Startup Applications. In the Startup Programs tab click the Add button. Name the Startup Program whatever you like and input any comments you like (or leave this field blank). In the command field add:

In Gnome 3 run gnome-session-properties to access startup applications.

$ syndaemon -t -k -i 2 -d &

When you are done, click the Add button in the Add Startup Program dialogue. Make sure the check box next to the startup program you have created is checked, in the list of additional startup programs. Close the Startup Applications Preferences window and you are done.

For KDE: (KDM)

Goto System Settings > Startup and Shutdown > Autostart, then click Add Program, enter:

 syndaemon -t -k -i 2 -d &

Then check Run in terminal.

Troubleshooting

xorg.conf.d/50-synaptics.conf doesn't seem to apply under GNOME and MATE

GNOME and MATE, by default, will overwrite various options for your touch-pad. This includes configurable features for which there is no graphical configuration within GNOME's system control panel. This may cause it to appear that /etc/X11/xorg.conf.d/50-synaptics.conf isn't applied. Please refer to the GNOME section in this article to prevent this behavior.

Touchpad_Synaptics#GNOME

ALPS Touchpads

This article or section needs expansion.

Reason: please use the first argument of the template to provide a brief explanation. (Discuss in Talk:Touchpad Synaptics#)

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For ALPS Touchpads, if the above configuration does not provide the desired results, try the following configuration instead:

/etc/X11/xorg.conf.d/50-synaptics.conf

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

  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  "Emulate3Buttons"   "on"
  EndSection

The touchpad is not working, Xorg.0.log shows "Query no Synaptics: 6003C8"

Due to the way synaptics is currently set-up, 2 instances of the synaptics module are loaded. We can recognize this situation by opening the xorg log file (/var/log/Xorg.0.log) and noticing this:

/var/log/Xorg.0.log

 [ 9304.803] (**) SynPS/2 Synaptics TouchPad: Applying InputClass "evdev touchpad catchall"
 [ 9304.803] (**) SynPS/2 Synaptics TouchPad: Applying InputClass "touchpad catchall"

Notice how 2 differently named instances of the module are being loaded. In some cases, this causes the touchpad to become nonfunctional.

We can prevent this double loading by adding MatchDevicePath "/dev/input/event*" to our /etc/X11/xorg.conf.d/50-synaptics.conf file:

/etc/X11/xorg.conf.d/50-synaptics.conf

 Section "InputClass"
       Identifier "touchpad catchall"
       Driver "synaptics"
       MatchIsTouchpad "on"
       MatchDevicePath "/dev/input/event*"
             Option "TapButton1" "1"
             Option "TapButton2" "2"
             Option "TapButton3" "3"
 EndSection

Restart X and check xorg logs again, the error should be gone and the touchpad should be functional.

related bugreport: FS#20830

Touchpad detected as "PS/2 Generic Mouse" or "Logitech PS/2 mouse"

This is caused by a kernel bug which was fixed in kernel version 3.3. Wrongly detected touchpads cannot be configured with the Synaptic input driver. To fix this, simply install the AUR package psmouse-alps-driver^AUR.

Among the affected notebooks are the following models:

Acer Aspire 7750G
Dell Latitude E6230, E6520, E6430 and E6530 (ALPS DualPoint TouchPad), Inspiron N5110 (ALPS GlidePoint), Inspiron 14R Turbo SE7420/SE7520 (ALPS GlidePoint)
Samsung NC110/NF210/QX310/QX410/QX510/SF310/SF410/SF510/RF410/RF510/RF710/RV515

You can check whether your touchpad is correctly detected by running:

$ xinput list

More information can be found in this thread.

Non-functional Synaptics Special Abilities (multi-tap, scrolling, etc.)

In some cases Synaptics touchpads only work partially. Features like two-finger scrolling or two-finger middle-click do not work even if properly enabled. This is probably related to the The touchpad is not working problem mentioned above. Fix is the same, prevent double module loading.

If preventing the module from loading twice does not solve your issue, try commenting out the toggle "MatchIsTouchpad" (which is now included by default in the synaptics config).

Disable touchpad upon external mouse detection

With the assistance of udev, it is possible to automatically disable the touchpad if an external mouse has been plugged in. To achieve this, add the following udev rules to /etc/udev/rules.d/01-touchpad.rules:

/etc/udev/rules.d/01-touchpad.rules

 ACTION=="add", SUBSYSTEM=="input", KERNEL=="mouse[0-9]", ENV{DISPLAY}=":0", ENV{XAUTHORITY}="/home/<your username>/.Xauthority", ENV{ID_CLASS}="mouse", ENV{REMOVE_CMD}="/usr/bin/synclient TouchpadOff=0", RUN+="/usr/bin/synclient TouchpadOff=1"

GDM stores Xauthority files in /var/run/gdm in a randomly-named directory. For some reason also multiple authority files may appear for a user. So you need udev rules like these:

ACTION=="add", KERNEL=="mouse[0-9]", SUBSYSTEM=="input", PROGRAM="/usr/bin/find /var/run/gdm -name *username* -print -quit", ENV{DISPLAY}=":0.0",
ENV{XAUTHORITY}="$result/database", RUN+="/usr/bin/synclient TouchpadOff=1"
ACTION=="remove", KERNEL=="mouse[0-9]", SUBSYSTEM=="input", PROGRAM="/usr/bin/find /var/run/gdm -name *username* -print -quit", ENV{DISPLAY}=":0.0",
ENV{XAUTHORITY}="$result/database", RUN+="/usr/bin/synclient TouchpadOff=0"

Note: udev rules must be a single line each, so format accordingly.

Note: These udev rules conflict with syndaemon (see #Using .xinitrc)

To disable touchpad and simultaneously kill syndaemon, you can use a rule like this:

ACTION=="add", KERNEL=="mouse[0-9]", SUBSYSTEM=="input", PROGRAM="/usr/bin/find /var/run/gdm -name *username* -print -quit", ENV{DISPLAY}=":0.0",ENV{XAUTHORITY}="$result/database", RUN+="/bin/sh -c '/usr/bin/synclient TouchpadOff=1 ; sleep 1; /bin/killall syndaemon; '"

If syndaemon starts automatically with mouse removal, then you can combine this with the remove rule above. If you need to start syndaemon yourself, then alter the command accordingly with your favourite syndaemon options.

Cursor Jump

Some users have their cursor inexplicably jump around the screen. There currently no patch for this, but the developers are aware of the problem and are working on it.

Another posibility is that you're experiencing IRQ losses related to the i8042 controller (this device handles the keyboard and the touchpad of many laptops), so you have two posibilities here:

1. rmmod && insmod the psmouse module. 2. append i8042.nomux=1 to the boot line and reboot your machine.

Touchpad device is not located at `/dev/input/*`

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

$ cat /proc/bus/input/devices

Search for an input device which has the name "SynPS/2 Synaptics TouchPad". The "Handlers" section of the output specifies what device you need to specify.

Example output:

$ cat /proc/bus/input/devices

 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

In this case, the Handlers are mouse0 and event1, so /dev/input/mouse0 would be used.

This article or section needs expansion.

Reason: please use the first argument of the template to provide a brief explanation. (Discuss in Talk:Touchpad Synaptics#)

Template:Box YELLOW

Firefox and special touchpad events

By default, Firefox is set up to do special events upon tapping or scrolling certain parts of your touchpad. You can edit the settings of those actions by typing about:config in your Firefox address bar. To alter these options, double-click on the line in question, changing "true" to "false" and vise versa.

To prevent Firefox from scrolling (backward/forward) through browser history and instead scroll through pages, edit these settings as shown:

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

To prevent Firefox from redirecting you to URLs formed from your clipboard content upon tapping the upper-right corner of your touchpad (or middle mouse button), set the following option to "false":

middlemouse.contentLoadURL = false

Opera: horizontal scrolling issues

Same as above. To fix it, go to Tools -> Preferences -> Advanced -> Shortcuts. Select "Opera Standard" mouse setup and click "Edit". In "Application" section:

assign key "Button 6" to command "Scroll left"
assign key "Button 7" to command "Scroll right"

Scrolling and multiple actions with Synaptics on LG Laptops

These problems seem to be occurring on several models of LG laptops. Symptoms include: when pressing Mouse Button 1, Synaptics interprets it as ScrollUP and a regular button 1 click; same goes for button 2.

The scrolling issue can be resolved by entering in xorg.conf:

/etc/X11/xorg.conf.d/xorg.conf

Option "UpDownScrolling" "0"

NOTE that this will make Synaptics interpret one button push as three. There is a patch written by Oskar Sandberg[1] that removes these clicks.

Apparently, when trying to compile this against the latest version of Synaptics it fails. The solution to this is using the GIT repository for Synaptics[2].

There is also a package build file in the AUR to automate this: xf86-input-synaptics-lg^AUR.

To build the package after downloading the tarball and unpacking it, execute:

$ cd synaptics-git

$ makepkg

Other external mouse issues

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

/etc/X11/xorg.conf.d/xorg.conf

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

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

/etc/X11/xorg.conf.d/xorg.conf

InputDevice    "Touchpad" "CorePointer"

and make your external device "SendCoreEvents":

/etc/X11/xorg.conf.d/xorg.conf

InputDevice    "USB Mouse" "SendCoreEvents"

finally add this to your external device's section:

/etc/X11/xorg.conf.d/xorg.conf

Option      "SendCoreEvents"    "true"

If all of the above does not 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 synchronization issues

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

/var/log/messages.log

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

This problem has no general solution, but there are several possible workarounds.

If you use CPU frequency scaling, avoid using the "ondemand" governor and use the "performance" governor when possible, as the touchpad may lose sync when the CPU frequency changes.
Avoid using an ACPI battery monitor.
Attempt to load psmouse with "proto=imps" option. To do that, add this line to your /etc/modprobe.d/modprobe.conf:

/etc/modprobe.d/modprobe.conf

options psmouse proto=imps

Try another desktop environment. Some users report that this problem only occurs when using XFCE or GNOME, for whatever reason

Delay between a button tap and the actual click

If you experience a delay between the tap on the touchpad and the actual click that is registered you need to enable FastTaps:

To do so, you should add Option "FastTaps" "1" to /etc/X11/xorg.conf.d/50-synaptics.conf so that you have:

/etc/X11/xorg.conf.d/50-synaptics.conf

 Section "InputClass"
      Identifier "Synaptics Touchpad"
      Driver "synaptics"
      ...
      Option "FastTaps" "1"
      ...
 EndSection

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

If you are using Xorg 7.4, you may get a warning like this from /var/log/Xorg.0.log, thais is because the driver will grab the event device for exclusive use when using the Linux 2.6 event protocol. When it fails, X will return this error message.

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 /etc/X11/xorg.conf.d/50-synaptics.conf:

/etc/X11/xorg.conf.d/50-synaptics.conf

 ...
 Option "GrabEventDevice" "''boolean''"
 ...

This will come into effect when X is restarted, though 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 re-enabled. This can be achieved by switching to a text console and then switching back to X.

Synaptics Loses Multitouch Detection After Rebooting From Windows

Many drivers include a firmware that is loaded into flash memory when the computer boots. This firmware is not necessarily cleared upon shutdown, and is not always compatible with Linux drivers. The only way to clear the flash memory is to shutdown completely rather than using reboot. It is generally considered best practice to never use reboot when switching between operating systems.

Buttonless TouchPads (aka ClickPads)

Some laptops have a special kind of touchpad which has the mouse buttons as part of the tracking plate, instead of being external buttons. For example HP series 4500 ProBooks, ThinkPad X220 and X1 ThinkPad series have this kind of a touchpad. By default whole button area is detected as a left button resulting in the second mouse button being unusable and click + drag will not work. Previously support for such devices was achieved by using third party patches, but from version 1.6.0 the synaptics driver has native multitouch support (using the mtdev library).

To enable other buttons modify the touchpad section in /etc/X11/xorg.conf.d/50-synaptics.conf (or better, of your custom synaptics configuration file prefixed with a higher number):

/etc/X11/xorg.conf.d/50-synaptics.conf

...
Option "ClickPad"         "true"
Option "EmulateMidButtonTime" "0"
Option "SoftButtonAreas"  "50% 0 82% 0 0 0 0 0"
...

These three options are the key, first one will enable multitouch support, second will disable middle button emulation (not supported for ClickPads), and third will define the button areas.

Format for the SoftButtonAreas option is (from man 4 synaptics):

RightButtonAreaLeft RightButtonAreaRight RightButtonAreaTop RightButtonAreaBottom  MiddleButtonAreaLeft MiddleButtonAreaRight MiddleButtonAreaTop MiddleButtonAreaBottom

The above example is commonly found in documentation or synaptics packages, and it translates to right half of the bottom 18% of the touchpad to be a right button. There is no middle button defined. If you want to define a middle button remember one key piece of information from the manual; edge set to 0 extends to infinity in that direction.

In the following example right button will occupy 40% of the rightmost part of the button area. We then proceed to setup the middle button to occupy 20% of the touchpad in a small area in the center.

   ...
   Option     "SoftButtonAreas"  "60% 0 82% 0 40% 59% 82% 0"
   ...

You can use synclient to check the new soft button areas:

   $ synclient -l | grep -i ButtonArea
       RightButtonAreaLeft     = 3914
       RightButtonAreaRight    = 0
       RightButtonAreaTop      = 3918
       RightButtonAreaBottom   = 0
       MiddleButtonAreaLeft    = 3100
       MiddleButtonAreaRight   = 3873
       MiddleButtonAreaTop     = 3918
       MiddleButtonAreaBottom  = 0

If your buttons aren't working, soft button areas are not changing, ensure you do not have a synaptics configuration file distributed by a package which is overriding your custom settings (ie. some AUR packages distribute configurations prefixed with very high numbers).

Touchpad detected as mouse (elantech touchpads)

This can happend on some laptops with elantech touchpad, for example ASUS x53s. In this situation you need psmouse-elantech^AUR package from AUR.

External Resources

Synaptics TouchPad driver