c6c748ef85
A chapter is added to describe the trackpoint packets. A section is added to describe the behaviour of the knob crc_enabled in sysfs. The introduction of the documentation only mentioned v1/v2, but in the last part it already contains explanation of v3 and v4. The introduction is updated. Signed-off-by: Ulrik De Bie <ulrik.debie-os@e2big.org> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
817 lines
22 KiB
Text
817 lines
22 KiB
Text
Elantech Touchpad Driver
|
|
========================
|
|
|
|
Copyright (C) 2007-2008 Arjan Opmeer <arjan@opmeer.net>
|
|
|
|
Extra information for hardware version 1 found and
|
|
provided by Steve Havelka
|
|
|
|
Version 2 (EeePC) hardware support based on patches
|
|
received from Woody at Xandros and forwarded to me
|
|
by user StewieGriffin at the eeeuser.com forum
|
|
|
|
|
|
Contents
|
|
~~~~~~~~
|
|
|
|
1. Introduction
|
|
2. Extra knobs
|
|
3. Differentiating hardware versions
|
|
4. Hardware version 1
|
|
4.1 Registers
|
|
4.2 Native relative mode 4 byte packet format
|
|
4.3 Native absolute mode 4 byte packet format
|
|
5. Hardware version 2
|
|
5.1 Registers
|
|
5.2 Native absolute mode 6 byte packet format
|
|
5.2.1 Parity checking and packet re-synchronization
|
|
5.2.2 One/Three finger touch
|
|
5.2.3 Two finger touch
|
|
6. Hardware version 3
|
|
6.1 Registers
|
|
6.2 Native absolute mode 6 byte packet format
|
|
6.2.1 One/Three finger touch
|
|
6.2.2 Two finger touch
|
|
7. Hardware version 4
|
|
7.1 Registers
|
|
7.2 Native absolute mode 6 byte packet format
|
|
7.2.1 Status packet
|
|
7.2.2 Head packet
|
|
7.2.3 Motion packet
|
|
8. Trackpoint (for Hardware version 3 and 4)
|
|
8.1 Registers
|
|
8.2 Native relative mode 6 byte packet format
|
|
8.2.1 Status Packet
|
|
|
|
|
|
|
|
1. Introduction
|
|
~~~~~~~~~~~~
|
|
|
|
Currently the Linux Elantech touchpad driver is aware of four different
|
|
hardware versions unimaginatively called version 1,version 2, version 3
|
|
and version 4. Version 1 is found in "older" laptops and uses 4 bytes per
|
|
packet. Version 2 seems to be introduced with the EeePC and uses 6 bytes
|
|
per packet, and provides additional features such as position of two fingers,
|
|
and width of the touch. Hardware version 3 uses 6 bytes per packet (and
|
|
for 2 fingers the concatenation of two 6 bytes packets) and allows tracking
|
|
of up to 3 fingers. Hardware version 4 uses 6 bytes per packet, and can
|
|
combine a status packet with multiple head or motion packets. Hardware version
|
|
4 allows tracking up to 5 fingers.
|
|
|
|
Some Hardware version 3 and version 4 also have a trackpoint which uses a
|
|
separate packet format. It is also 6 bytes per packet.
|
|
|
|
The driver tries to support both hardware versions and should be compatible
|
|
with the Xorg Synaptics touchpad driver and its graphical configuration
|
|
utilities.
|
|
|
|
Note that a mouse button is also associated with either the touchpad or the
|
|
trackpoint when a trackpoint is available. Disabling the Touchpad in xorg
|
|
(TouchPadOff=0) will also disable the buttons associated with the touchpad.
|
|
|
|
Additionally the operation of the touchpad can be altered by adjusting the
|
|
contents of some of its internal registers. These registers are represented
|
|
by the driver as sysfs entries under /sys/bus/serio/drivers/psmouse/serio?
|
|
that can be read from and written to.
|
|
|
|
Currently only the registers for hardware version 1 are somewhat understood.
|
|
Hardware version 2 seems to use some of the same registers but it is not
|
|
known whether the bits in the registers represent the same thing or might
|
|
have changed their meaning.
|
|
|
|
On top of that, some register settings have effect only when the touchpad is
|
|
in relative mode and not in absolute mode. As the Linux Elantech touchpad
|
|
driver always puts the hardware into absolute mode not all information
|
|
mentioned below can be used immediately. But because there is no freely
|
|
available Elantech documentation the information is provided here anyway for
|
|
completeness sake.
|
|
|
|
|
|
/////////////////////////////////////////////////////////////////////////////
|
|
|
|
|
|
2. Extra knobs
|
|
~~~~~~~~~~~
|
|
|
|
Currently the Linux Elantech touchpad driver provides three extra knobs under
|
|
/sys/bus/serio/drivers/psmouse/serio? for the user.
|
|
|
|
* debug
|
|
|
|
Turn different levels of debugging ON or OFF.
|
|
|
|
By echoing "0" to this file all debugging will be turned OFF.
|
|
|
|
Currently a value of "1" will turn on some basic debugging and a value of
|
|
"2" will turn on packet debugging. For hardware version 1 the default is
|
|
OFF. For version 2 the default is "1".
|
|
|
|
Turning packet debugging on will make the driver dump every packet
|
|
received to the syslog before processing it. Be warned that this can
|
|
generate quite a lot of data!
|
|
|
|
* paritycheck
|
|
|
|
Turns parity checking ON or OFF.
|
|
|
|
By echoing "0" to this file parity checking will be turned OFF. Any
|
|
non-zero value will turn it ON. For hardware version 1 the default is ON.
|
|
For version 2 the default it is OFF.
|
|
|
|
Hardware version 1 provides basic data integrity verification by
|
|
calculating a parity bit for the last 3 bytes of each packet. The driver
|
|
can check these bits and reject any packet that appears corrupted. Using
|
|
this knob you can bypass that check.
|
|
|
|
Hardware version 2 does not provide the same parity bits. Only some basic
|
|
data consistency checking can be done. For now checking is disabled by
|
|
default. Currently even turning it on will do nothing.
|
|
|
|
* crc_enabled
|
|
|
|
Sets crc_enabled to 0/1. The name "crc_enabled" is the official name of
|
|
this integrity check, even though it is not an actual cyclic redundancy
|
|
check.
|
|
|
|
Depending on the state of crc_enabled, certain basic data integrity
|
|
verification is done by the driver on hardware version 3 and 4. The
|
|
driver will reject any packet that appears corrupted. Using this knob,
|
|
The state of crc_enabled can be altered with this knob.
|
|
|
|
Reading the crc_enabled value will show the active value. Echoing
|
|
"0" or "1" to this file will set the state to "0" or "1".
|
|
|
|
/////////////////////////////////////////////////////////////////////////////
|
|
|
|
3. Differentiating hardware versions
|
|
=================================
|
|
|
|
To detect the hardware version, read the version number as param[0].param[1].param[2]
|
|
|
|
4 bytes version: (after the arrow is the name given in the Dell-provided driver)
|
|
02.00.22 => EF013
|
|
02.06.00 => EF019
|
|
In the wild, there appear to be more versions, such as 00.01.64, 01.00.21,
|
|
02.00.00, 02.00.04, 02.00.06.
|
|
|
|
6 bytes:
|
|
02.00.30 => EF113
|
|
02.08.00 => EF023
|
|
02.08.XX => EF123
|
|
02.0B.00 => EF215
|
|
04.01.XX => Scroll_EF051
|
|
04.02.XX => EF051
|
|
In the wild, there appear to be more versions, such as 04.03.01, 04.04.11. There
|
|
appears to be almost no difference, except for EF113, which does not report
|
|
pressure/width and has different data consistency checks.
|
|
|
|
Probably all the versions with param[0] <= 01 can be considered as
|
|
4 bytes/firmware 1. The versions < 02.08.00, with the exception of 02.00.30, as
|
|
4 bytes/firmware 2. Everything >= 02.08.00 can be considered as 6 bytes.
|
|
|
|
/////////////////////////////////////////////////////////////////////////////
|
|
|
|
4. Hardware version 1
|
|
==================
|
|
|
|
4.1 Registers
|
|
~~~~~~~~~
|
|
|
|
By echoing a hexadecimal value to a register it contents can be altered.
|
|
|
|
For example:
|
|
|
|
echo -n 0x16 > reg_10
|
|
|
|
* reg_10
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
B C T D L A S E
|
|
|
|
E: 1 = enable smart edges unconditionally
|
|
S: 1 = enable smart edges only when dragging
|
|
A: 1 = absolute mode (needs 4 byte packets, see reg_11)
|
|
L: 1 = enable drag lock (see reg_22)
|
|
D: 1 = disable dynamic resolution
|
|
T: 1 = disable tapping
|
|
C: 1 = enable corner tap
|
|
B: 1 = swap left and right button
|
|
|
|
* reg_11
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
1 0 0 H V 1 F P
|
|
|
|
P: 1 = enable parity checking for relative mode
|
|
F: 1 = enable native 4 byte packet mode
|
|
V: 1 = enable vertical scroll area
|
|
H: 1 = enable horizontal scroll area
|
|
|
|
* reg_20
|
|
|
|
single finger width?
|
|
|
|
* reg_21
|
|
|
|
scroll area width (small: 0x40 ... wide: 0xff)
|
|
|
|
* reg_22
|
|
|
|
drag lock time out (short: 0x14 ... long: 0xfe;
|
|
0xff = tap again to release)
|
|
|
|
* reg_23
|
|
|
|
tap make timeout?
|
|
|
|
* reg_24
|
|
|
|
tap release timeout?
|
|
|
|
* reg_25
|
|
|
|
smart edge cursor speed (0x02 = slow, 0x03 = medium, 0x04 = fast)
|
|
|
|
* reg_26
|
|
|
|
smart edge activation area width?
|
|
|
|
|
|
4.2 Native relative mode 4 byte packet format
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
byte 0:
|
|
bit 7 6 5 4 3 2 1 0
|
|
c c p2 p1 1 M R L
|
|
|
|
L, R, M = 1 when Left, Right, Middle mouse button pressed
|
|
some models have M as byte 3 odd parity bit
|
|
when parity checking is enabled (reg_11, P = 1):
|
|
p1..p2 = byte 1 and 2 odd parity bit
|
|
c = 1 when corner tap detected
|
|
|
|
byte 1:
|
|
bit 7 6 5 4 3 2 1 0
|
|
dx7 dx6 dx5 dx4 dx3 dx2 dx1 dx0
|
|
|
|
dx7..dx0 = x movement; positive = right, negative = left
|
|
byte 1 = 0xf0 when corner tap detected
|
|
|
|
byte 2:
|
|
bit 7 6 5 4 3 2 1 0
|
|
dy7 dy6 dy5 dy4 dy3 dy2 dy1 dy0
|
|
|
|
dy7..dy0 = y movement; positive = up, negative = down
|
|
|
|
byte 3:
|
|
parity checking enabled (reg_11, P = 1):
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
w h n1 n0 ds3 ds2 ds1 ds0
|
|
|
|
normally:
|
|
ds3..ds0 = scroll wheel amount and direction
|
|
positive = down or left
|
|
negative = up or right
|
|
when corner tap detected:
|
|
ds0 = 1 when top right corner tapped
|
|
ds1 = 1 when bottom right corner tapped
|
|
ds2 = 1 when bottom left corner tapped
|
|
ds3 = 1 when top left corner tapped
|
|
n1..n0 = number of fingers on touchpad
|
|
only models with firmware 2.x report this, models with
|
|
firmware 1.x seem to map one, two and three finger taps
|
|
directly to L, M and R mouse buttons
|
|
h = 1 when horizontal scroll action
|
|
w = 1 when wide finger touch?
|
|
|
|
otherwise (reg_11, P = 0):
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
ds7 ds6 ds5 ds4 ds3 ds2 ds1 ds0
|
|
|
|
ds7..ds0 = vertical scroll amount and direction
|
|
negative = up
|
|
positive = down
|
|
|
|
|
|
4.3 Native absolute mode 4 byte packet format
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
EF013 and EF019 have a special behaviour (due to a bug in the firmware?), and
|
|
when 1 finger is touching, the first 2 position reports must be discarded.
|
|
This counting is reset whenever a different number of fingers is reported.
|
|
|
|
byte 0:
|
|
firmware version 1.x:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
D U p1 p2 1 p3 R L
|
|
|
|
L, R = 1 when Left, Right mouse button pressed
|
|
p1..p3 = byte 1..3 odd parity bit
|
|
D, U = 1 when rocker switch pressed Up, Down
|
|
|
|
firmware version 2.x:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
n1 n0 p2 p1 1 p3 R L
|
|
|
|
L, R = 1 when Left, Right mouse button pressed
|
|
p1..p3 = byte 1..3 odd parity bit
|
|
n1..n0 = number of fingers on touchpad
|
|
|
|
byte 1:
|
|
firmware version 1.x:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
f 0 th tw x9 x8 y9 y8
|
|
|
|
tw = 1 when two finger touch
|
|
th = 1 when three finger touch
|
|
f = 1 when finger touch
|
|
|
|
firmware version 2.x:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
. . . . x9 x8 y9 y8
|
|
|
|
byte 2:
|
|
bit 7 6 5 4 3 2 1 0
|
|
x7 x6 x5 x4 x3 x2 x1 x0
|
|
|
|
x9..x0 = absolute x value (horizontal)
|
|
|
|
byte 3:
|
|
bit 7 6 5 4 3 2 1 0
|
|
y7 y6 y5 y4 y3 y2 y1 y0
|
|
|
|
y9..y0 = absolute y value (vertical)
|
|
|
|
|
|
/////////////////////////////////////////////////////////////////////////////
|
|
|
|
|
|
5. Hardware version 2
|
|
==================
|
|
|
|
|
|
5.1 Registers
|
|
~~~~~~~~~
|
|
|
|
By echoing a hexadecimal value to a register it contents can be altered.
|
|
|
|
For example:
|
|
|
|
echo -n 0x56 > reg_10
|
|
|
|
* reg_10
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
0 1 0 1 0 1 D 0
|
|
|
|
D: 1 = enable drag and drop
|
|
|
|
* reg_11
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
1 0 0 0 S 0 1 0
|
|
|
|
S: 1 = enable vertical scroll
|
|
|
|
* reg_21
|
|
|
|
unknown (0x00)
|
|
|
|
* reg_22
|
|
|
|
drag and drop release time out (short: 0x70 ... long 0x7e;
|
|
0x7f = never i.e. tap again to release)
|
|
|
|
|
|
5.2 Native absolute mode 6 byte packet format
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
5.2.1 Parity checking and packet re-synchronization
|
|
There is no parity checking, however some consistency checks can be performed.
|
|
|
|
For instance for EF113:
|
|
SA1= packet[0];
|
|
A1 = packet[1];
|
|
B1 = packet[2];
|
|
SB1= packet[3];
|
|
C1 = packet[4];
|
|
D1 = packet[5];
|
|
if( (((SA1 & 0x3C) != 0x3C) && ((SA1 & 0xC0) != 0x80)) || // check Byte 1
|
|
(((SA1 & 0x0C) != 0x0C) && ((SA1 & 0xC0) == 0x80)) || // check Byte 1 (one finger pressed)
|
|
(((SA1 & 0xC0) != 0x80) && (( A1 & 0xF0) != 0x00)) || // check Byte 2
|
|
(((SB1 & 0x3E) != 0x38) && ((SA1 & 0xC0) != 0x80)) || // check Byte 4
|
|
(((SB1 & 0x0E) != 0x08) && ((SA1 & 0xC0) == 0x80)) || // check Byte 4 (one finger pressed)
|
|
(((SA1 & 0xC0) != 0x80) && (( C1 & 0xF0) != 0x00)) ) // check Byte 5
|
|
// error detected
|
|
|
|
For all the other ones, there are just a few constant bits:
|
|
if( ((packet[0] & 0x0C) != 0x04) ||
|
|
((packet[3] & 0x0f) != 0x02) )
|
|
// error detected
|
|
|
|
|
|
In case an error is detected, all the packets are shifted by one (and packet[0] is discarded).
|
|
|
|
5.2.2 One/Three finger touch
|
|
~~~~~~~~~~~~~~~~
|
|
|
|
byte 0:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
n1 n0 w3 w2 . . R L
|
|
|
|
L, R = 1 when Left, Right mouse button pressed
|
|
n1..n0 = number of fingers on touchpad
|
|
|
|
byte 1:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
p7 p6 p5 p4 x11 x10 x9 x8
|
|
|
|
byte 2:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
x7 x6 x5 x4 x3 x2 x1 x0
|
|
|
|
x11..x0 = absolute x value (horizontal)
|
|
|
|
byte 3:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
n4 vf w1 w0 . . . b2
|
|
|
|
n4 = set if more than 3 fingers (only in 3 fingers mode)
|
|
vf = a kind of flag ? (only on EF123, 0 when finger is over one
|
|
of the buttons, 1 otherwise)
|
|
w3..w0 = width of the finger touch (not EF113)
|
|
b2 (on EF113 only, 0 otherwise), b2.R.L indicates one button pressed:
|
|
0 = none
|
|
1 = Left
|
|
2 = Right
|
|
3 = Middle (Left and Right)
|
|
4 = Forward
|
|
5 = Back
|
|
6 = Another one
|
|
7 = Another one
|
|
|
|
byte 4:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
p3 p1 p2 p0 y11 y10 y9 y8
|
|
|
|
p7..p0 = pressure (not EF113)
|
|
|
|
byte 5:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
y7 y6 y5 y4 y3 y2 y1 y0
|
|
|
|
y11..y0 = absolute y value (vertical)
|
|
|
|
|
|
5.2.3 Two finger touch
|
|
~~~~~~~~~~~~~~~~
|
|
|
|
Note that the two pairs of coordinates are not exactly the coordinates of the
|
|
two fingers, but only the pair of the lower-left and upper-right coordinates.
|
|
So the actual fingers might be situated on the other diagonal of the square
|
|
defined by these two points.
|
|
|
|
byte 0:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
n1 n0 ay8 ax8 . . R L
|
|
|
|
L, R = 1 when Left, Right mouse button pressed
|
|
n1..n0 = number of fingers on touchpad
|
|
|
|
byte 1:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
ax7 ax6 ax5 ax4 ax3 ax2 ax1 ax0
|
|
|
|
ax8..ax0 = lower-left finger absolute x value
|
|
|
|
byte 2:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
ay7 ay6 ay5 ay4 ay3 ay2 ay1 ay0
|
|
|
|
ay8..ay0 = lower-left finger absolute y value
|
|
|
|
byte 3:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
. . by8 bx8 . . . .
|
|
|
|
byte 4:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
bx7 bx6 bx5 bx4 bx3 bx2 bx1 bx0
|
|
|
|
bx8..bx0 = upper-right finger absolute x value
|
|
|
|
byte 5:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
by7 by8 by5 by4 by3 by2 by1 by0
|
|
|
|
by8..by0 = upper-right finger absolute y value
|
|
|
|
/////////////////////////////////////////////////////////////////////////////
|
|
|
|
6. Hardware version 3
|
|
==================
|
|
|
|
6.1 Registers
|
|
~~~~~~~~~
|
|
* reg_10
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
0 0 0 0 R F T A
|
|
|
|
A: 1 = enable absolute tracking
|
|
T: 1 = enable two finger mode auto correct
|
|
F: 1 = disable ABS Position Filter
|
|
R: 1 = enable real hardware resolution
|
|
|
|
6.2 Native absolute mode 6 byte packet format
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
1 and 3 finger touch shares the same 6-byte packet format, except that
|
|
3 finger touch only reports the position of the center of all three fingers.
|
|
|
|
Firmware would send 12 bytes of data for 2 finger touch.
|
|
|
|
Note on debounce:
|
|
In case the box has unstable power supply or other electricity issues, or
|
|
when number of finger changes, F/W would send "debounce packet" to inform
|
|
driver that the hardware is in debounce status.
|
|
The debouce packet has the following signature:
|
|
byte 0: 0xc4
|
|
byte 1: 0xff
|
|
byte 2: 0xff
|
|
byte 3: 0x02
|
|
byte 4: 0xff
|
|
byte 5: 0xff
|
|
When we encounter this kind of packet, we just ignore it.
|
|
|
|
6.2.1 One/Three finger touch
|
|
~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
byte 0:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
n1 n0 w3 w2 0 1 R L
|
|
|
|
L, R = 1 when Left, Right mouse button pressed
|
|
n1..n0 = number of fingers on touchpad
|
|
|
|
byte 1:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
p7 p6 p5 p4 x11 x10 x9 x8
|
|
|
|
byte 2:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
x7 x6 x5 x4 x3 x2 x1 x0
|
|
|
|
x11..x0 = absolute x value (horizontal)
|
|
|
|
byte 3:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
0 0 w1 w0 0 0 1 0
|
|
|
|
w3..w0 = width of the finger touch
|
|
|
|
byte 4:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
p3 p1 p2 p0 y11 y10 y9 y8
|
|
|
|
p7..p0 = pressure
|
|
|
|
byte 5:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
y7 y6 y5 y4 y3 y2 y1 y0
|
|
|
|
y11..y0 = absolute y value (vertical)
|
|
|
|
6.2.2 Two finger touch
|
|
~~~~~~~~~~~~~~~~
|
|
|
|
The packet format is exactly the same for two finger touch, except the hardware
|
|
sends two 6 byte packets. The first packet contains data for the first finger,
|
|
the second packet has data for the second finger. So for two finger touch a
|
|
total of 12 bytes are sent.
|
|
|
|
/////////////////////////////////////////////////////////////////////////////
|
|
|
|
7. Hardware version 4
|
|
==================
|
|
|
|
7.1 Registers
|
|
~~~~~~~~~
|
|
* reg_07
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
0 0 0 0 0 0 0 A
|
|
|
|
A: 1 = enable absolute tracking
|
|
|
|
7.2 Native absolute mode 6 byte packet format
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
v4 hardware is a true multitouch touchpad, capable of tracking up to 5 fingers.
|
|
Unfortunately, due to PS/2's limited bandwidth, its packet format is rather
|
|
complex.
|
|
|
|
Whenever the numbers or identities of the fingers changes, the hardware sends a
|
|
status packet to indicate how many and which fingers is on touchpad, followed by
|
|
head packets or motion packets. A head packet contains data of finger id, finger
|
|
position (absolute x, y values), width, and pressure. A motion packet contains
|
|
two fingers' position delta.
|
|
|
|
For example, when status packet tells there are 2 fingers on touchpad, then we
|
|
can expect two following head packets. If the finger status doesn't change,
|
|
the following packets would be motion packets, only sending delta of finger
|
|
position, until we receive a status packet.
|
|
|
|
One exception is one finger touch. when a status packet tells us there is only
|
|
one finger, the hardware would just send head packets afterwards.
|
|
|
|
7.2.1 Status packet
|
|
~~~~~~~~~~~~~
|
|
|
|
byte 0:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
. . . . 0 1 R L
|
|
|
|
L, R = 1 when Left, Right mouse button pressed
|
|
|
|
byte 1:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
. . . ft4 ft3 ft2 ft1 ft0
|
|
|
|
ft4 ft3 ft2 ft1 ft0 ftn = 1 when finger n is on touchpad
|
|
|
|
byte 2: not used
|
|
|
|
byte 3:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
. . . 1 0 0 0 0
|
|
|
|
constant bits
|
|
|
|
byte 4:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
p . . . . . . .
|
|
|
|
p = 1 for palm
|
|
|
|
byte 5: not used
|
|
|
|
7.2.2 Head packet
|
|
~~~~~~~~~~~
|
|
|
|
byte 0:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
w3 w2 w1 w0 0 1 R L
|
|
|
|
L, R = 1 when Left, Right mouse button pressed
|
|
w3..w0 = finger width (spans how many trace lines)
|
|
|
|
byte 1:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
p7 p6 p5 p4 x11 x10 x9 x8
|
|
|
|
byte 2:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
x7 x6 x5 x4 x3 x2 x1 x0
|
|
|
|
x11..x0 = absolute x value (horizontal)
|
|
|
|
byte 3:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
id2 id1 id0 1 0 0 0 1
|
|
|
|
id2..id0 = finger id
|
|
|
|
byte 4:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
p3 p1 p2 p0 y11 y10 y9 y8
|
|
|
|
p7..p0 = pressure
|
|
|
|
byte 5:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
y7 y6 y5 y4 y3 y2 y1 y0
|
|
|
|
y11..y0 = absolute y value (vertical)
|
|
|
|
7.2.3 Motion packet
|
|
~~~~~~~~~~~~~
|
|
|
|
byte 0:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
id2 id1 id0 w 0 1 R L
|
|
|
|
L, R = 1 when Left, Right mouse button pressed
|
|
id2..id0 = finger id
|
|
w = 1 when delta overflows (> 127 or < -128), in this case
|
|
firmware sends us (delta x / 5) and (delta y / 5)
|
|
|
|
byte 1:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
x7 x6 x5 x4 x3 x2 x1 x0
|
|
|
|
x7..x0 = delta x (two's complement)
|
|
|
|
byte 2:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
y7 y6 y5 y4 y3 y2 y1 y0
|
|
|
|
y7..y0 = delta y (two's complement)
|
|
|
|
byte 3:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
id2 id1 id0 1 0 0 1 0
|
|
|
|
id2..id0 = finger id
|
|
|
|
byte 4:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
x7 x6 x5 x4 x3 x2 x1 x0
|
|
|
|
x7..x0 = delta x (two's complement)
|
|
|
|
byte 5:
|
|
|
|
bit 7 6 5 4 3 2 1 0
|
|
y7 y6 y5 y4 y3 y2 y1 y0
|
|
|
|
y7..y0 = delta y (two's complement)
|
|
|
|
byte 0 ~ 2 for one finger
|
|
byte 3 ~ 5 for another
|
|
|
|
|
|
8. Trackpoint (for Hardware version 3 and 4)
|
|
=========================================
|
|
8.1 Registers
|
|
~~~~~~~~~
|
|
No special registers have been identified.
|
|
|
|
8.2 Native relative mode 6 byte packet format
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
8.2.1 Status Packet
|
|
~~~~~~~~~~~~~
|
|
|
|
byte 0:
|
|
bit 7 6 5 4 3 2 1 0
|
|
0 0 sx sy 0 M R L
|
|
byte 1:
|
|
bit 7 6 5 4 3 2 1 0
|
|
~sx 0 0 0 0 0 0 0
|
|
byte 2:
|
|
bit 7 6 5 4 3 2 1 0
|
|
~sy 0 0 0 0 0 0 0
|
|
byte 3:
|
|
bit 7 6 5 4 3 2 1 0
|
|
0 0 ~sy ~sx 0 1 1 0
|
|
byte 4:
|
|
bit 7 6 5 4 3 2 1 0
|
|
x7 x6 x5 x4 x3 x2 x1 x0
|
|
byte 5:
|
|
bit 7 6 5 4 3 2 1 0
|
|
y7 y6 y5 y4 y3 y2 y1 y0
|
|
|
|
|
|
x and y are written in two's complement spread
|
|
over 9 bits with sx/sy the relative top bit and
|
|
x7..x0 and y7..y0 the lower bits.
|
|
~sx is the inverse of sx, ~sy is the inverse of sy.
|
|
The sign of y is opposite to what the input driver
|
|
expects for a relative movement
|