From 1dc6edec127e1fdb89d246189c232fe635d2f921 Mon Sep 17 00:00:00 2001 From: JJ Ding Date: Fri, 9 Sep 2011 10:31:58 -0700 Subject: Input: elantech - add v4 hardware support v4 hardware is a true multitouch capable touchpad (up to 5 fingers). The packet format is quite complex, please see protocol document for reference. Signed-off-by: JJ Ding Signed-off-by: Dmitry Torokhov --- Documentation/input/elantech.txt | 170 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 170 insertions(+) (limited to 'Documentation/input/elantech.txt') diff --git a/Documentation/input/elantech.txt b/Documentation/input/elantech.txt index cee08ee..5602eb7 100644 --- a/Documentation/input/elantech.txt +++ b/Documentation/input/elantech.txt @@ -32,6 +32,12 @@ Contents 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 @@ -573,3 +579,167 @@ 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 -- cgit v1.1