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authorLinus Torvalds <torvalds@linux-foundation.org>2011-05-24 11:58:49 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-05-24 11:58:49 -0700
commit4637f40f200063973553ce3c4c1ac6c247e4535c (patch)
treeff317a0dfb67cae313a208d120edd5102730044d /Documentation
parent5129df03d0c44b2d5a5f9d7d52f3b079706b9a8f (diff)
parentb73077eb03f510a84b102fb97640e595a958403c (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (40 commits) Input: ADP5589 - new driver for I2C Keypad Decoder and I/O Expander Input: tsc2007 - add X, Y and Z fuzz factors to platform data Input: tsc2007 - add poll_period parameter to platform data Input: tsc2007 - add poll_delay parameter to platform data Input: tsc2007 - add max_rt parameter to platform data Input: tsc2007 - debounce pressure measurement Input: ad714x - fix captouch wheel option algorithm Input: ad714x - allow platform code to specify irqflags Input: ad714x - fix threshold and completion interrupt masks Input: ad714x - fix up input configuration Input: elantech - remove support for proprietary X driver Input: elantech - report multitouch with proper ABS_MT messages Input: elantech - export pressure and width when supported Input: elantech - describe further the protocol Input: atmel_tsadcc - correct call to input_free_device Input: add driver FSL MPR121 capacitive touch sensor Input: remove useless synchronize_rcu() calls Input: ads7846 - fix gpio_pendown configuration Input: ads7846 - add possibility to use external vref on ads7846 Input: rotary-encoder - add support for half-period encoders ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/input/elantech.txt123
-rw-r--r--Documentation/input/rotary-encoder.txt13
2 files changed, 113 insertions, 23 deletions
diff --git a/Documentation/input/elantech.txt b/Documentation/input/elantech.txt
index 56941ae1f5d..db798af5ef9 100644
--- a/Documentation/input/elantech.txt
+++ b/Documentation/input/elantech.txt
@@ -34,7 +34,8 @@ Contents
Currently the Linux Elantech touchpad driver is aware of two different
hardware versions unimaginatively called version 1 and version 2. 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.
+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.
The driver tries to support both hardware versions and should be compatible
with the Xorg Synaptics touchpad driver and its graphical configuration
@@ -94,18 +95,44 @@ Currently the Linux Elantech touchpad driver provides two extra knobs under
can check these bits and reject any packet that appears corrupted. Using
this knob you can bypass that check.
- It is not known yet whether hardware version 2 provides the same parity
- bits. Hence checking is disabled by default. Currently even turning it on
- will do nothing.
-
+ 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.
/////////////////////////////////////////////////////////////////////////////
+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.
+
+/////////////////////////////////////////////////////////////////////////////
-3. Hardware version 1
+4. Hardware version 1
==================
-3.1 Registers
+4.1 Registers
~~~~~~~~~
By echoing a hexadecimal value to a register it contents can be altered.
@@ -168,7 +195,7 @@ For example:
smart edge activation area width?
-3.2 Native relative mode 4 byte packet format
+4.2 Native relative mode 4 byte packet format
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
byte 0:
@@ -226,9 +253,13 @@ byte 3:
positive = down
-3.3 Native absolute mode 4 byte packet format
+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:
@@ -279,11 +310,11 @@ byte 3:
/////////////////////////////////////////////////////////////////////////////
-4. Hardware version 2
+5. Hardware version 2
==================
-4.1 Registers
+5.1 Registers
~~~~~~~~~
By echoing a hexadecimal value to a register it contents can be altered.
@@ -316,16 +347,41 @@ For example:
0x7f = never i.e. tap again to release)
-4.2 Native absolute mode 6 byte packet format
+5.2 Native absolute mode 6 byte packet format
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-4.2.1 One finger touch
+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).
+
+5.2.1 One/Three finger touch
~~~~~~~~~~~~~~~~
byte 0:
bit 7 6 5 4 3 2 1 0
- n1 n0 . . . . R L
+ n1 n0 w3 w2 . . R L
L, R = 1 when Left, Right mouse button pressed
n1..n0 = numbers of fingers on touchpad
@@ -333,24 +389,40 @@ byte 0:
byte 1:
bit 7 6 5 4 3 2 1 0
- . . . . . x10 x9 x8
+ p7 p6 p5 p4 . x10 x9 x8
byte 2:
bit 7 6 5 4 3 2 1 0
- x7 x6 x5 x4 x4 x2 x1 x0
+ x7 x6 x5 x4 x3 x2 x1 x0
x10..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
- . . . . . . y9 y8
+ p3 p1 p2 p0 . . y9 y8
+
+ p7..p0 = pressure (not EF113)
byte 5:
@@ -363,6 +435,11 @@ byte 5:
4.2.2 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
@@ -376,14 +453,14 @@ byte 1:
bit 7 6 5 4 3 2 1 0
ax7 ax6 ax5 ax4 ax3 ax2 ax1 ax0
- ax8..ax0 = first finger absolute x value
+ 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 = first finger absolute y value
+ ay8..ay0 = lower-left finger absolute y value
byte 3:
@@ -395,11 +472,11 @@ byte 4:
bit 7 6 5 4 3 2 1 0
bx7 bx6 bx5 bx4 bx3 bx2 bx1 bx0
- bx8..bx0 = second finger absolute x value
+ 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 = second finger absolute y value
+ by8..by0 = upper-right finger absolute y value
diff --git a/Documentation/input/rotary-encoder.txt b/Documentation/input/rotary-encoder.txt
index 943e8f6f2b1..92e68bce13a 100644
--- a/Documentation/input/rotary-encoder.txt
+++ b/Documentation/input/rotary-encoder.txt
@@ -9,6 +9,9 @@ peripherals with two wires. The outputs are phase-shifted by 90 degrees
and by triggering on falling and rising edges, the turn direction can
be determined.
+Some encoders have both outputs low in stable states, whereas others also have
+a stable state with both outputs high (half-period mode).
+
The phase diagram of these two outputs look like this:
_____ _____ _____
@@ -26,6 +29,8 @@ The phase diagram of these two outputs look like this:
|<-------->|
one step
+ |<-->|
+ one step (half-period mode)
For more information, please see
http://en.wikipedia.org/wiki/Rotary_encoder
@@ -34,6 +39,13 @@ For more information, please see
1. Events / state machine
-------------------------
+In half-period mode, state a) and c) above are used to determine the
+rotational direction based on the last stable state. Events are reported in
+states b) and d) given that the new stable state is different from the last
+(i.e. the rotation was not reversed half-way).
+
+Otherwise, the following apply:
+
a) Rising edge on channel A, channel B in low state
This state is used to recognize a clockwise turn
@@ -96,6 +108,7 @@ static struct rotary_encoder_platform_data my_rotary_encoder_info = {
.gpio_b = GPIO_ROTARY_B,
.inverted_a = 0,
.inverted_b = 0,
+ .half_period = false,
};
static struct platform_device rotary_encoder_device = {