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1Apple Touchpad Driver (appletouch)
2----------------------------------
3 Copyright (C) 2005 Stelian Pop <stelian@popies.net>
4
5appletouch is a Linux kernel driver for the USB touchpad found on post
6February 2005 Apple Alu Powerbooks.
7
8This driver is derived from Johannes Berg's appletrackpad driver[1], but it has
9been improved in some areas:
10 * appletouch is a full kernel driver, no userspace program is necessary
11 * appletouch can be interfaced with the synaptics X11 driver, in order
12 to have touchpad acceleration, scrolling, etc.
13
14Credits go to Johannes Berg for reverse-engineering the touchpad protocol,
15Frank Arnold for further improvements, and Alex Harper for some additional
16information about the inner workings of the touchpad sensors.
17
18Usage:
19------
20
21In order to use the touchpad in the basic mode, compile the driver and load
22the module. A new input device will be detected and you will be able to read
23the mouse data from /dev/input/mice (using gpm, or X11).
24
25In X11, you can configure the touchpad to use the synaptics X11 driver, which
26will give additional functionalities, like acceleration, scrolling, 2 finger
27tap for middle button mouse emulation, 3 finger tap for right button mouse
28emulation, etc. In order to do this, make sure you're using a recent version of
29the synaptics driver (tested with 0.14.2, available from [2]), and configure a
30new input device in your X11 configuration file (take a look below for an
31example). For additional configuration, see the synaptics driver documentation.
32
33 Section "InputDevice"
34 Identifier "Synaptics Touchpad"
35 Driver "synaptics"
36 Option "SendCoreEvents" "true"
37 Option "Device" "/dev/input/mice"
38 Option "Protocol" "auto-dev"
39 Option "LeftEdge" "0"
40 Option "RightEdge" "850"
41 Option "TopEdge" "0"
42 Option "BottomEdge" "645"
43 Option "MinSpeed" "0.4"
44 Option "MaxSpeed" "1"
45 Option "AccelFactor" "0.02"
46 Option "FingerLow" "0"
47 Option "FingerHigh" "30"
48 Option "MaxTapMove" "20"
49 Option "MaxTapTime" "100"
50 Option "HorizScrollDelta" "0"
51 Option "VertScrollDelta" "30"
52 Option "SHMConfig" "on"
53 EndSection
54
55 Section "ServerLayout"
56 ...
57 InputDevice "Mouse"
58 InputDevice "Synaptics Touchpad"
59 ...
60 EndSection
61
62Fuzz problems:
63--------------
64
65The touchpad sensors are very sensitive to heat, and will generate a lot of
66noise when the temperature changes. This is especially true when you power-on
67the laptop for the first time.
68
69The appletouch driver tries to handle this noise and auto adapt itself, but it
70is not perfect. If finger movements are not recognized anymore, try reloading
71the driver.
72
73You can activate debugging using the 'debug' module parameter. A value of 0
74deactivates any debugging, 1 activates tracing of invalid samples, 2 activates
75full tracing (each sample is being traced):
76 modprobe appletouch debug=1
77 or
78 echo "1" > /sys/module/appletouch/parameters/debug
79
80Links:
81------
82
83[1]: http://johannes.sipsolutions.net/PowerBook/touchpad/
84[2]: http://web.telia.com/~u89404340/touchpad/index.html