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 and October 2005 Apple Aluminium 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. Michael
17Hanselmann added support for the October 2005 models.
18
19Usage:
20------
21
22In order to use the touchpad in the basic mode, compile the driver and load
23the module. A new input device will be detected and you will be able to read
24the mouse data from /dev/input/mice (using gpm, or X11).
25
26In X11, you can configure the touchpad to use the synaptics X11 driver, which
27will give additional functionalities, like acceleration, scrolling, 2 finger
28tap for middle button mouse emulation, 3 finger tap for right button mouse
29emulation, etc. In order to do this, make sure you're using a recent version of
30the synaptics driver (tested with 0.14.2, available from [2]), and configure a
31new input device in your X11 configuration file (take a look below for an
32example). For additional configuration, see the synaptics driver documentation.
33
34	Section "InputDevice"
35        	Identifier      "Synaptics Touchpad"
36	        Driver          "synaptics"
37		Option          "SendCoreEvents"        "true"
38		Option          "Device"                "/dev/input/mice"
39		Option          "Protocol"              "auto-dev"
40		Option		"LeftEdge"		"0"
41		Option		"RightEdge"		"850"
42		Option		"TopEdge"		"0"
43		Option		"BottomEdge"		"645"
44		Option		"MinSpeed"		"0.4"
45		Option		"MaxSpeed"		"1"
46		Option		"AccelFactor"		"0.02"
47		Option		"FingerLow"		"0"
48		Option		"FingerHigh"		"30"
49		Option		"MaxTapMove"		"20"
50		Option		"MaxTapTime"		"100"
51		Option		"HorizScrollDelta"	"0"
52		Option		"VertScrollDelta"	"30"
53		Option		"SHMConfig"		"on"
54	EndSection
55
56	Section "ServerLayout"
57		...
58		InputDevice	"Mouse"
59		InputDevice	"Synaptics Touchpad"
60	...
61	EndSection
62
63Fuzz problems:
64--------------
65
66The touchpad sensors are very sensitive to heat, and will generate a lot of
67noise when the temperature changes. This is especially true when you power-on
68the laptop for the first time.
69
70The appletouch driver tries to handle this noise and auto adapt itself, but it
71is not perfect. If finger movements are not recognized anymore, try reloading
72the driver.
73
74You can activate debugging using the 'debug' module parameter. A value of 0
75deactivates any debugging, 1 activates tracing of invalid samples, 2 activates
76full tracing (each sample is being traced):
77	modprobe appletouch debug=1
78		or
79	echo "1" > /sys/module/appletouch/parameters/debug
80
81Links:
82------
83
84[1]: http://johannes.sipsolutions.net/PowerBook/touchpad/
85[2]: http://web.archive.org/web/*/http://web.telia.com/~u89404340/touchpad/index.html
86