1 Elantech Touchpad Driver
2 ========================
3
4 Copyright (C) 2007-2008 Arjan Opmeer <a
5
6 Extra information for hardware version
7 provided by Steve Havelka
8
9 Version 2 (EeePC) hardware support bas
10 received from Woody at Xandros and for
11 by user StewieGriffin at the eeeuser.c
12
13 .. Contents
14
15 1. Introduction
16 2. Extra knobs
17 3. Differentiating hardware versions
18 4. Hardware version 1
19 4.1 Registers
20 4.2 Native relative mode 4 byte packet for
21 4.3 Native absolute mode 4 byte packet for
22 5. Hardware version 2
23 5.1 Registers
24 5.2 Native absolute mode 6 byte packet for
25 5.2.1 Parity checking and packet re-sy
26 5.2.2 One/Three finger touch
27 5.2.3 Two finger touch
28 6. Hardware version 3
29 6.1 Registers
30 6.2 Native absolute mode 6 byte packet for
31 6.2.1 One/Three finger touch
32 6.2.2 Two finger touch
33 7. Hardware version 4
34 7.1 Registers
35 7.2 Native absolute mode 6 byte packet for
36 7.2.1 Status packet
37 7.2.2 Head packet
38 7.2.3 Motion packet
39 8. Trackpoint (for Hardware version 3 and 4)
40 8.1 Registers
41 8.2 Native relative mode 6 byte packet for
42 8.2.1 Status Packet
43
44
45
46 Introduction
47 ~~~~~~~~~~~~
48
49 Currently the Linux Elantech touchpad driver i
50 hardware versions unimaginatively called versi
51 and version 4. Version 1 is found in "older" l
52 packet. Version 2 seems to be introduced with
53 per packet, and provides additional features s
54 and width of the touch. Hardware version 3 us
55 for 2 fingers the concatenation of two 6 bytes
56 of up to 3 fingers. Hardware version 4 uses 6
57 combine a status packet with multiple head or
58 4 allows tracking up to 5 fingers.
59
60 Some Hardware version 3 and version 4 also hav
61 separate packet format. It is also 6 bytes per
62
63 The driver tries to support both hardware vers
64 with the Xorg Synaptics touchpad driver and it
65 utilities.
66
67 Note that a mouse button is also associated wi
68 trackpoint when a trackpoint is available. Di
69 (TouchPadOff=0) will also disable the buttons
70
71 Additionally the operation of the touchpad can
72 contents of some of its internal registers. Th
73 by the driver as sysfs entries under /sys/bus/
74 that can be read from and written to.
75
76 Currently only the registers for hardware vers
77 Hardware version 2 seems to use some of the sa
78 known whether the bits in the registers repres
79 have changed their meaning.
80
81 On top of that, some register settings have ef
82 in relative mode and not in absolute mode. As
83 driver always puts the hardware into absolute
84 mentioned below can be used immediately. But b
85 available Elantech documentation the informati
86 completeness sake.
87
88
89 Extra knobs
90 ~~~~~~~~~~~
91
92 Currently the Linux Elantech touchpad driver p
93 /sys/bus/serio/drivers/psmouse/serio? for the
94
95 * debug
96
97 Turn different levels of debugging ON or OF
98
99 By echoing "0" to this file all debugging w
100
101 Currently a value of "1" will turn on some
102 "2" will turn on packet debugging. For hard
103 OFF. For version 2 the default is "1".
104
105 Turning packet debugging on will make the d
106 received to the syslog before processing it
107 generate quite a lot of data!
108
109 * paritycheck
110
111 Turns parity checking ON or OFF.
112
113 By echoing "0" to this file parity checking
114 non-zero value will turn it ON. For hardwar
115 For version 2 the default it is OFF.
116
117 Hardware version 1 provides basic data inte
118 calculating a parity bit for the last 3 byt
119 can check these bits and reject any packet
120 this knob you can bypass that check.
121
122 Hardware version 2 does not provide the sam
123 data consistency checking can be done. For
124 default. Currently even turning it on will
125
126 * crc_enabled
127
128 Sets crc_enabled to 0/1. The name "crc_enab
129 this integrity check, even though it is not
130 check.
131
132 Depending on the state of crc_enabled, cert
133 verification is done by the driver on hardw
134 driver will reject any packet that appears
135 The state of crc_enabled can be altered wit
136
137 Reading the crc_enabled value will show the
138 "0" or "1" to this file will set the state
139
140 Differentiating hardware versions
141 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
142
143 To detect the hardware version, read the versi
144
145 4 bytes version: (after the arrow is the name
146 02.00.22 => EF013
147 02.06.00 => EF019
148
149 In the wild, there appear to be more versions,
150 02.00.00, 02.00.04, 02.00.06::
151
152 6 bytes:
153 02.00.30 => EF113
154 02.08.00 => EF023
155 02.08.XX => EF123
156 02.0B.00 => EF215
157 04.01.XX => Scroll_EF051
158 04.02.XX => EF051
159
160 In the wild, there appear to be more versions,
161 appears to be almost no difference, except for
162 pressure/width and has different data consiste
163
164 Probably all the versions with param[0] <= 01
165 4 bytes/firmware 1. The versions < 02.08.00, w
166 4 bytes/firmware 2. Everything >= 02.08.00 can
167
168
169 Hardware version 1
170 ~~~~~~~~~~~~~~~~~~
171
172 Registers
173 ---------
174
175 By echoing a hexadecimal value to a register i
176
177 For example::
178
179 echo -n 0x16 > reg_10
180
181 * reg_10::
182
183 bit 7 6 5 4 3 2 1 0
184 B C T D L A S E
185
186 E: 1 = enable smart edges uncondition
187 S: 1 = enable smart edges only when d
188 A: 1 = absolute mode (needs 4 byte pa
189 L: 1 = enable drag lock (see reg_22)
190 D: 1 = disable dynamic resolution
191 T: 1 = disable tapping
192 C: 1 = enable corner tap
193 B: 1 = swap left and right button
194
195 * reg_11::
196
197 bit 7 6 5 4 3 2 1 0
198 1 0 0 H V 1 F P
199
200 P: 1 = enable parity checking for rel
201 F: 1 = enable native 4 byte packet mo
202 V: 1 = enable vertical scroll area
203 H: 1 = enable horizontal scroll area
204
205 * reg_20::
206
207 single finger width?
208
209 * reg_21::
210
211 scroll area width (small: 0x40 ... wi
212
213 * reg_22::
214
215 drag lock time out (short: 0x14 ... l
216 0xff = tap again
217
218 * reg_23::
219
220 tap make timeout?
221
222 * reg_24::
223
224 tap release timeout?
225
226 * reg_25::
227
228 smart edge cursor speed (0x02 = slow,
229
230 * reg_26::
231
232 smart edge activation area width?
233
234
235 Native relative mode 4 byte packet format
236 -----------------------------------------
237
238 byte 0::
239
240 bit 7 6 5 4 3 2 1 0
241 c c p2 p1 1 M R L
242
243 L, R, M = 1 when Left, Right, Middle
244 some models have M as byte 3 odd p
245 when parity checking is enabled (reg_
246 p1..p2 = byte 1 and 2 odd parity b
247 c = 1 when corner tap detected
248
249 byte 1::
250
251 bit 7 6 5 4 3 2 1 0
252 dx7 dx6 dx5 dx4 dx3 dx2 dx1 dx0
253
254 dx7..dx0 = x movement; positive = r
255 byte 1 = 0xf0 when corner tap detecte
256
257 byte 2::
258
259 bit 7 6 5 4 3 2 1 0
260 dy7 dy6 dy5 dy4 dy3 dy2 dy1 dy0
261
262 dy7..dy0 = y movement; positive = u
263
264 byte 3::
265
266 parity checking enabled (reg_11, P = 1):
267
268 bit 7 6 5 4 3 2 1 0
269 w h n1 n0 ds3 ds2 ds1 ds0
270
271 normally:
272 ds3..ds0 = scroll wheel amount
273 positive = down or l
274 negative = up or rig
275 when corner tap detected:
276 ds0 = 1 when top right corner t
277 ds1 = 1 when bottom right corne
278 ds2 = 1 when bottom left corner
279 ds3 = 1 when top left corner ta
280 n1..n0 = number of fingers on touc
281 only models with firmware 2.x r
282 firmware 1.x seem to map one, t
283 directly to L, M and R mouse bu
284 h = 1 when horizontal scroll actio
285 w = 1 when wide finger touch?
286
287 otherwise (reg_11, P = 0):
288
289 bit 7 6 5 4 3 2 1 0
290 ds7 ds6 ds5 ds4 ds3 ds2 ds1 ds0
291
292 ds7..ds0 = vertical scroll amount
293 negative = up
294 positive = down
295
296
297 Native absolute mode 4 byte packet format
298 -----------------------------------------
299
300 EF013 and EF019 have a special behaviour (due
301 when 1 finger is touching, the first 2 positio
302 This counting is reset whenever a different nu
303
304 byte 0::
305
306 firmware version 1.x:
307
308 bit 7 6 5 4 3 2 1 0
309 D U p1 p2 1 p3 R L
310
311 L, R = 1 when Left, Right mouse bu
312 p1..p3 = byte 1..3 odd parity bit
313 D, U = 1 when rocker switch presse
314
315 firmware version 2.x:
316
317 bit 7 6 5 4 3 2 1 0
318 n1 n0 p2 p1 1 p3 R L
319
320 L, R = 1 when Left, Right mouse bu
321 p1..p3 = byte 1..3 odd parity bit
322 n1..n0 = number of fingers on touc
323
324 byte 1::
325
326 firmware version 1.x:
327
328 bit 7 6 5 4 3 2 1 0
329 f 0 th tw x9 x8 y9 y8
330
331 tw = 1 when two finger touch
332 th = 1 when three finger touch
333 f = 1 when finger touch
334
335 firmware version 2.x:
336
337 bit 7 6 5 4 3 2 1 0
338 . . . . x9 x8 y9 y8
339
340 byte 2::
341
342 bit 7 6 5 4 3 2 1 0
343 x7 x6 x5 x4 x3 x2 x1 x0
344
345 x9..x0 = absolute x value (horizontal
346
347 byte 3::
348
349 bit 7 6 5 4 3 2 1 0
350 y7 y6 y5 y4 y3 y2 y1 y0
351
352 y9..y0 = absolute y value (vertical)
353
354
355 Hardware version 2
356 ~~~~~~~~~~~~~~~~~~
357
358
359 Registers
360 ---------
361
362 By echoing a hexadecimal value to a register i
363
364 For example::
365
366 echo -n 0x56 > reg_10
367
368 * reg_10::
369
370 bit 7 6 5 4 3 2 1 0
371 0 1 0 1 0 1 D 0
372
373 D: 1 = enable drag and drop
374
375 * reg_11::
376
377 bit 7 6 5 4 3 2 1 0
378 1 0 0 0 S 0 1 0
379
380 S: 1 = enable vertical scroll
381
382 * reg_21::
383
384 unknown (0x00)
385
386 * reg_22::
387
388 drag and drop release time out (short
389 0x7f = neve
390
391
392 Native absolute mode 6 byte packet format
393 -----------------------------------------
394
395 Parity checking and packet re-synchronization
396 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
397
398 There is no parity checking, however some cons
399
400 For instance for EF113::
401
402 SA1= packet[0];
403 A1 = packet[1];
404 B1 = packet[2];
405 SB1= packet[3];
406 C1 = packet[4];
407 D1 = packet[5];
408 if( (((SA1 & 0x3C) != 0x3C) && ((SA1 &
409 (((SA1 & 0x0C) != 0x0C) && ((SA1 &
410 (((SA1 & 0xC0) != 0x80) && (( A1 &
411 (((SB1 & 0x3E) != 0x38) && ((SA1 &
412 (((SB1 & 0x0E) != 0x08) && ((SA1 &
413 (((SA1 & 0xC0) != 0x80) && (( C1 &
414 // error detected
415
416 For all the other ones, there are just a few c
417
418 if( ((packet[0] & 0x0C) != 0x04) ||
419 ((packet[3] & 0x0f) != 0x02) )
420 // error detected
421
422
423 In case an error is detected, all the packets
424
425 One/Three finger touch
426 ^^^^^^^^^^^^^^^^^^^^^^
427
428 byte 0::
429
430 bit 7 6 5 4 3 2 1 0
431 n1 n0 w3 w2 . . R L
432
433 L, R = 1 when Left, Right mouse butto
434 n1..n0 = number of fingers on touchpa
435
436 byte 1::
437
438 bit 7 6 5 4 3 2 1 0
439 p7 p6 p5 p4 x11 x10 x9 x8
440
441 byte 2::
442
443 bit 7 6 5 4 3 2 1 0
444 x7 x6 x5 x4 x3 x2 x1 x0
445
446 x11..x0 = absolute x value (horizonta
447
448 byte 3::
449
450 bit 7 6 5 4 3 2 1 0
451 n4 vf w1 w0 . . . b2
452
453 n4 = set if more than 3 fingers (only
454 vf = a kind of flag ? (only on EF123,
455 of the buttons, 1 otherwise)
456 w3..w0 = width of the finger touch (n
457 b2 (on EF113 only, 0 otherwise), b2.R
458 0 = none
459 1 = Left
460 2 = Right
461 3 = Middle (Left and Right)
462 4 = Forward
463 5 = Back
464 6 = Another one
465 7 = Another one
466
467 byte 4::
468
469 bit 7 6 5 4 3 2 1 0
470 p3 p1 p2 p0 y11 y10 y9 y8
471
472 p7..p0 = pressure (not EF113)
473
474 byte 5::
475
476 bit 7 6 5 4 3 2 1 0
477 y7 y6 y5 y4 y3 y2 y1 y0
478
479 y11..y0 = absolute y value (vertical)
480
481
482 Two finger touch
483 ^^^^^^^^^^^^^^^^
484
485 Note that the two pairs of coordinates are not
486 two fingers, but only the pair of the lower-le
487 So the actual fingers might be situated on the
488 defined by these two points.
489
490 byte 0::
491
492 bit 7 6 5 4 3 2 1 0
493 n1 n0 ay8 ax8 . . R L
494
495 L, R = 1 when Left, Right mouse butto
496 n1..n0 = number of fingers on touchpa
497
498 byte 1::
499
500 bit 7 6 5 4 3 2 1 0
501 ax7 ax6 ax5 ax4 ax3 ax2 ax1 ax0
502
503 ax8..ax0 = lower-left finger absolute
504
505 byte 2::
506
507 bit 7 6 5 4 3 2 1 0
508 ay7 ay6 ay5 ay4 ay3 ay2 ay1 ay0
509
510 ay8..ay0 = lower-left finger absolute
511
512 byte 3::
513
514 bit 7 6 5 4 3 2 1 0
515 . . by8 bx8 . . . .
516
517 byte 4::
518
519 bit 7 6 5 4 3 2 1 0
520 bx7 bx6 bx5 bx4 bx3 bx2 bx1 bx0
521
522 bx8..bx0 = upper-right finger absolut
523
524 byte 5::
525
526 bit 7 6 5 4 3 2 1 0
527 by7 by8 by5 by4 by3 by2 by1 by0
528
529 by8..by0 = upper-right finger absolut
530
531 Hardware version 3
532 ~~~~~~~~~~~~~~~~~~
533
534 Registers
535 ---------
536
537 * reg_10::
538
539 bit 7 6 5 4 3 2 1 0
540 0 0 0 0 R F T A
541
542 A: 1 = enable absolute tracking
543 T: 1 = enable two finger mode auto co
544 F: 1 = disable ABS Position Filter
545 R: 1 = enable real hardware resolutio
546
547 Native absolute mode 6 byte packet format
548 -----------------------------------------
549
550 1 and 3 finger touch shares the same 6-byte pa
551 3 finger touch only reports the position of th
552
553 Firmware would send 12 bytes of data for 2 fin
554
555 Note on debounce:
556 In case the box has unstable power supply or o
557 when number of finger changes, F/W would send
558 driver that the hardware is in debounce status
559 The debouce packet has the following signature
560
561 byte 0: 0xc4
562 byte 1: 0xff
563 byte 2: 0xff
564 byte 3: 0x02
565 byte 4: 0xff
566 byte 5: 0xff
567
568 When we encounter this kind of packet, we just
569
570 One/Three finger touch
571 ^^^^^^^^^^^^^^^^^^^^^^
572
573 byte 0::
574
575 bit 7 6 5 4 3 2 1 0
576 n1 n0 w3 w2 0 1 R L
577
578 L, R = 1 when Left, Right mouse button
579 n1..n0 = number of fingers on touchpad
580
581 byte 1::
582
583 bit 7 6 5 4 3 2 1 0
584 p7 p6 p5 p4 x11 x10 x9 x8
585
586 byte 2::
587
588 bit 7 6 5 4 3 2 1 0
589 x7 x6 x5 x4 x3 x2 x1 x0
590
591 x11..x0 = absolute x value (horizontal
592
593 byte 3::
594
595 bit 7 6 5 4 3 2 1 0
596 0 0 w1 w0 0 0 1 0
597
598 w3..w0 = width of the finger touch
599
600 byte 4::
601
602 bit 7 6 5 4 3 2 1 0
603 p3 p1 p2 p0 y11 y10 y9 y8
604
605 p7..p0 = pressure
606
607 byte 5::
608
609 bit 7 6 5 4 3 2 1 0
610 y7 y6 y5 y4 y3 y2 y1 y0
611
612 y11..y0 = absolute y value (vertical)
613
614 Two finger touch
615 ^^^^^^^^^^^^^^^^
616
617 The packet format is exactly the same for two
618 sends two 6 byte packets. The first packet con
619 the second packet has data for the second fing
620 total of 12 bytes are sent.
621
622 Hardware version 4
623 ~~~~~~~~~~~~~~~~~~
624
625 Registers
626 ---------
627
628 * reg_07::
629
630 bit 7 6 5 4 3 2 1 0
631 0 0 0 0 0 0 0 A
632
633 A: 1 = enable absolute tracking
634
635 Native absolute mode 6 byte packet format
636 -----------------------------------------
637
638 v4 hardware is a true multitouch touchpad, cap
639 Unfortunately, due to PS/2's limited bandwidth
640 complex.
641
642 Whenever the numbers or identities of the fing
643 status packet to indicate how many and which f
644 head packets or motion packets. A head packet
645 position (absolute x, y values), width, and pr
646 two fingers' position delta.
647
648 For example, when status packet tells there ar
649 can expect two following head packets. If the
650 the following packets would be motion packets,
651 position, until we receive a status packet.
652
653 One exception is one finger touch. when a stat
654 one finger, the hardware would just send head
655
656 Status packet
657 ^^^^^^^^^^^^^
658
659 byte 0::
660
661 bit 7 6 5 4 3 2 1 0
662 . . . . 0 1 R L
663
664 L, R = 1 when Left, Right mouse butto
665
666 byte 1::
667
668 bit 7 6 5 4 3 2 1 0
669 . . . ft4 ft3 ft2 ft1 ft0
670
671 ft4 ft3 ft2 ft1 ft0 ftn = 1 when fing
672
673 byte 2::
674
675 not used
676
677 byte 3::
678
679 bit 7 6 5 4 3 2 1 0
680 . . . 1 0 0 0 0
681
682 constant bits
683
684 byte 4::
685
686 bit 7 6 5 4 3 2 1 0
687 p . . . . . . .
688
689 p = 1 for palm
690
691 byte 5::
692
693 not used
694
695 Head packet
696 ^^^^^^^^^^^
697
698 byte 0::
699
700 bit 7 6 5 4 3 2 1 0
701 w3 w2 w1 w0 0 1 R L
702
703 L, R = 1 when Left, Right mouse button
704 w3..w0 = finger width (spans how many
705
706 byte 1::
707
708 bit 7 6 5 4 3 2 1 0
709 p7 p6 p5 p4 x11 x10 x9 x8
710
711 byte 2::
712
713 bit 7 6 5 4 3 2 1 0
714 x7 x6 x5 x4 x3 x2 x1 x0
715
716 x11..x0 = absolute x value (horizontal
717
718 byte 3::
719
720 bit 7 6 5 4 3 2 1 0
721 id2 id1 id0 1 0 0 0 1
722
723 id2..id0 = finger id
724
725 byte 4::
726
727 bit 7 6 5 4 3 2 1 0
728 p3 p1 p2 p0 y11 y10 y9 y8
729
730 p7..p0 = pressure
731
732 byte 5::
733
734 bit 7 6 5 4 3 2 1 0
735 y7 y6 y5 y4 y3 y2 y1 y0
736
737 y11..y0 = absolute y value (vertical)
738
739 Motion packet
740 ^^^^^^^^^^^^^
741
742 byte 0::
743
744 bit 7 6 5 4 3 2 1 0
745 id2 id1 id0 w 0 1 R L
746
747 L, R = 1 when Left, Right mouse button
748 id2..id0 = finger id
749 w = 1 when delta overflows (> 127 or <
750 firmware sends us (delta x / 5) and (de
751
752 byte 1::
753
754 bit 7 6 5 4 3 2 1 0
755 x7 x6 x5 x4 x3 x2 x1 x0
756
757 x7..x0 = delta x (two's complement)
758
759 byte 2::
760
761 bit 7 6 5 4 3 2 1 0
762 y7 y6 y5 y4 y3 y2 y1 y0
763
764 y7..y0 = delta y (two's complement)
765
766 byte 3::
767
768 bit 7 6 5 4 3 2 1 0
769 id2 id1 id0 1 0 0 1 0
770
771 id2..id0 = finger id
772
773 byte 4::
774
775 bit 7 6 5 4 3 2 1 0
776 x7 x6 x5 x4 x3 x2 x1 x0
777
778 x7..x0 = delta x (two's complement)
779
780 byte 5::
781
782 bit 7 6 5 4 3 2 1 0
783 y7 y6 y5 y4 y3 y2 y1 y0
784
785 y7..y0 = delta y (two's complement)
786
787 byte 0 ~ 2 for one finger
788 byte 3 ~ 5 for another
789
790
791 Trackpoint (for Hardware version 3 and 4)
792 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
793
794 Registers
795 ---------
796
797 No special registers have been identified.
798
799 Native relative mode 6 byte packet format
800 -----------------------------------------
801
802 Status Packet
803 ^^^^^^^^^^^^^
804
805 byte 0::
806
807 bit 7 6 5 4 3 2 1 0
808 0 0 sx sy 0 M R L
809
810 byte 1::
811
812 bit 7 6 5 4 3 2 1 0
813 ~sx 0 0 0 0 0 0 0
814
815 byte 2::
816
817 bit 7 6 5 4 3 2 1 0
818 ~sy 0 0 0 0 0 0 0
819
820 byte 3::
821
822 bit 7 6 5 4 3 2 1 0
823 0 0 ~sy ~sx 0 1 1 0
824
825 byte 4::
826
827 bit 7 6 5 4 3 2 1 0
828 x7 x6 x5 x4 x3 x2 x1 x0
829
830 byte 5::
831
832 bit 7 6 5 4 3 2 1 0
833 y7 y6 y5 y4 y3 y2 y1 y0
834
835
836 x and y are written in two's compleme
837 over 9 bits with sx/sy the relati
838 x7..x0 and y7..y0 the lower bits.
839 ~sx is the inverse of sx, ~sy is the
840 The sign of y is opposite to what the
841 expects for a relative movement
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