Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 841 insertions, 0 deletions

diff --git a/Documentation/input/devices/elantech.rst b/Documentation/input/devices/elantech.rst
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+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
+
+
+
+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.
+
+
+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".
+
+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.
+
+
+Hardware version 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?
+
+
+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
+
+
+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)
+
+
+Hardware version 2
+~~~~~~~~~~~~~~~~~~
+
+
+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)
+
+
+Native absolute mode 6 byte packet format
+-----------------------------------------
+
+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).
+
+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)
+
+
+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
+
+Hardware version 3
+~~~~~~~~~~~~~~~~~~
+
+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
+
+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.
+
+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)
+
+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.
+
+Hardware version 4
+~~~~~~~~~~~~~~~~~~
+
+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
+
+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.
+
+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
+
+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)
+
+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
+
+
+Trackpoint (for Hardware version 3 and 4)
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Registers
+---------
+
+No special registers have been identified.
+
+Native relative mode 6 byte packet format
+-----------------------------------------
+
+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