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diff --git a/Documentation/input/devices/elantech.rst b/Documentation/input/devices/elantech.rst new file mode 100644 index 000000000..c3374a7ce --- /dev/null +++ b/Documentation/input/devices/elantech.rst @@ -0,0 +1,841 @@ +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 |