summaryrefslogtreecommitdiff
path: root/Documentation/input
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/input')
-rw-r--r--Documentation/input/elantech.txt123
-rw-r--r--Documentation/input/event-codes.txt262
-rw-r--r--Documentation/input/joystick-parport.txt2
-rw-r--r--Documentation/input/rotary-encoder.txt15
-rw-r--r--Documentation/input/walkera0701.txt2
5 files changed, 378 insertions, 26 deletions
diff --git a/Documentation/input/elantech.txt b/Documentation/input/elantech.txt
index 56941ae1f5db..db798af5ef98 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/event-codes.txt b/Documentation/input/event-codes.txt
new file mode 100644
index 000000000000..23fcb05175be
--- /dev/null
+++ b/Documentation/input/event-codes.txt
@@ -0,0 +1,262 @@
+The input protocol uses a map of types and codes to express input device values
+to userspace. This document describes the types and codes and how and when they
+may be used.
+
+A single hardware event generates multiple input events. Each input event
+contains the new value of a single data item. A special event type, EV_SYN, is
+used to separate input events into packets of input data changes occurring at
+the same moment in time. In the following, the term "event" refers to a single
+input event encompassing a type, code, and value.
+
+The input protocol is a stateful protocol. Events are emitted only when values
+of event codes have changed. However, the state is maintained within the Linux
+input subsystem; drivers do not need to maintain the state and may attempt to
+emit unchanged values without harm. Userspace may obtain the current state of
+event code values using the EVIOCG* ioctls defined in linux/input.h. The event
+reports supported by a device are also provided by sysfs in
+class/input/event*/device/capabilities/, and the properties of a device are
+provided in class/input/event*/device/properties.
+
+Types:
+==========
+Types are groupings of codes under a logical input construct. Each type has a
+set of applicable codes to be used in generating events. See the Codes section
+for details on valid codes for each type.
+
+* EV_SYN:
+ - Used as markers to separate events. Events may be separated in time or in
+ space, such as with the multitouch protocol.
+
+* EV_KEY:
+ - Used to describe state changes of keyboards, buttons, or other key-like
+ devices.
+
+* EV_REL:
+ - Used to describe relative axis value changes, e.g. moving the mouse 5 units
+ to the left.
+
+* EV_ABS:
+ - Used to describe absolute axis value changes, e.g. describing the
+ coordinates of a touch on a touchscreen.
+
+* EV_MSC:
+ - Used to describe miscellaneous input data that do not fit into other types.
+
+* EV_SW:
+ - Used to describe binary state input switches.
+
+* EV_LED:
+ - Used to turn LEDs on devices on and off.
+
+* EV_SND:
+ - Used to output sound to devices.
+
+* EV_REP:
+ - Used for autorepeating devices.
+
+* EV_FF:
+ - Used to send force feedback commands to an input device.
+
+* EV_PWR:
+ - A special type for power button and switch input.
+
+* EV_FF_STATUS:
+ - Used to receive force feedback device status.
+
+Codes:
+==========
+Codes define the precise type of event.
+
+EV_SYN:
+----------
+EV_SYN event values are undefined. Their usage is defined only by when they are
+sent in the evdev event stream.
+
+* SYN_REPORT:
+ - Used to synchronize and separate events into packets of input data changes
+ occurring at the same moment in time. For example, motion of a mouse may set
+ the REL_X and REL_Y values for one motion, then emit a SYN_REPORT. The next
+ motion will emit more REL_X and REL_Y values and send another SYN_REPORT.
+
+* SYN_CONFIG:
+ - TBD
+
+* SYN_MT_REPORT:
+ - Used to synchronize and separate touch events. See the
+ multi-touch-protocol.txt document for more information.
+
+* SYN_DROPPED:
+ - Used to indicate buffer overrun in the evdev client's event queue.
+ Client should ignore all events up to and including next SYN_REPORT
+ event and query the device (using EVIOCG* ioctls) to obtain its
+ current state.
+
+EV_KEY:
+----------
+EV_KEY events take the form KEY_<name> or BTN_<name>. For example, KEY_A is used
+to represent the 'A' key on a keyboard. When a key is depressed, an event with
+the key's code is emitted with value 1. When the key is released, an event is
+emitted with value 0. Some hardware send events when a key is repeated. These
+events have a value of 2. In general, KEY_<name> is used for keyboard keys, and
+BTN_<name> is used for other types of momentary switch events.
+
+A few EV_KEY codes have special meanings:
+
+* BTN_TOOL_<name>:
+ - These codes are used in conjunction with input trackpads, tablets, and
+ touchscreens. These devices may be used with fingers, pens, or other tools.
+ When an event occurs and a tool is used, the corresponding BTN_TOOL_<name>
+ code should be set to a value of 1. When the tool is no longer interacting
+ with the input device, the BTN_TOOL_<name> code should be reset to 0. All
+ trackpads, tablets, and touchscreens should use at least one BTN_TOOL_<name>
+ code when events are generated.
+
+* BTN_TOUCH:
+ BTN_TOUCH is used for touch contact. While an input tool is determined to be
+ within meaningful physical contact, the value of this property must be set
+ to 1. Meaningful physical contact may mean any contact, or it may mean
+ contact conditioned by an implementation defined property. For example, a
+ touchpad may set the value to 1 only when the touch pressure rises above a
+ certain value. BTN_TOUCH may be combined with BTN_TOOL_<name> codes. For
+ example, a pen tablet may set BTN_TOOL_PEN to 1 and BTN_TOUCH to 0 while the
+ pen is hovering over but not touching the tablet surface.
+
+Note: For appropriate function of the legacy mousedev emulation driver,
+BTN_TOUCH must be the first evdev code emitted in a synchronization frame.
+
+Note: Historically a touch device with BTN_TOOL_FINGER and BTN_TOUCH was
+interpreted as a touchpad by userspace, while a similar device without
+BTN_TOOL_FINGER was interpreted as a touchscreen. For backwards compatibility
+with current userspace it is recommended to follow this distinction. In the
+future, this distinction will be deprecated and the device properties ioctl
+EVIOCGPROP, defined in linux/input.h, will be used to convey the device type.
+
+* BTN_TOOL_FINGER, BTN_TOOL_DOUBLETAP, BTN_TOOL_TRIPLETAP, BTN_TOOL_QUADTAP:
+ - These codes denote one, two, three, and four finger interaction on a
+ trackpad or touchscreen. For example, if the user uses two fingers and moves
+ them on the touchpad in an effort to scroll content on screen,
+ BTN_TOOL_DOUBLETAP should be set to value 1 for the duration of the motion.
+ Note that all BTN_TOOL_<name> codes and the BTN_TOUCH code are orthogonal in
+ purpose. A trackpad event generated by finger touches should generate events
+ for one code from each group. At most only one of these BTN_TOOL_<name>
+ codes should have a value of 1 during any synchronization frame.
+
+Note: Historically some drivers emitted multiple of the finger count codes with
+a value of 1 in the same synchronization frame. This usage is deprecated.
+
+Note: In multitouch drivers, the input_mt_report_finger_count() function should
+be used to emit these codes. Please see multi-touch-protocol.txt for details.
+
+EV_REL:
+----------
+EV_REL events describe relative changes in a property. For example, a mouse may
+move to the left by a certain number of units, but its absolute position in
+space is unknown. If the absolute position is known, EV_ABS codes should be used
+instead of EV_REL codes.
+
+A few EV_REL codes have special meanings:
+
+* REL_WHEEL, REL_HWHEEL:
+ - These codes are used for vertical and horizontal scroll wheels,
+ respectively.
+
+EV_ABS:
+----------
+EV_ABS events describe absolute changes in a property. For example, a touchpad
+may emit coordinates for a touch location.
+
+A few EV_ABS codes have special meanings:
+
+* ABS_DISTANCE:
+ - Used to describe the distance of a tool from an interaction surface. This
+ event should only be emitted while the tool is hovering, meaning in close
+ proximity of the device and while the value of the BTN_TOUCH code is 0. If
+ the input device may be used freely in three dimensions, consider ABS_Z
+ instead.
+
+* ABS_MT_<name>:
+ - Used to describe multitouch input events. Please see
+ multi-touch-protocol.txt for details.
+
+EV_SW:
+----------
+EV_SW events describe stateful binary switches. For example, the SW_LID code is
+used to denote when a laptop lid is closed.
+
+Upon binding to a device or resuming from suspend, a driver must report
+the current switch state. This ensures that the device, kernel, and userspace
+state is in sync.
+
+Upon resume, if the switch state is the same as before suspend, then the input
+subsystem will filter out the duplicate switch state reports. The driver does
+not need to keep the state of the switch at any time.
+
+EV_MSC:
+----------
+EV_MSC events are used for input and output events that do not fall under other
+categories.
+
+EV_LED:
+----------
+EV_LED events are used for input and output to set and query the state of
+various LEDs on devices.
+
+EV_REP:
+----------
+EV_REP events are used for specifying autorepeating events.
+
+EV_SND:
+----------
+EV_SND events are used for sending sound commands to simple sound output
+devices.
+
+EV_FF:
+----------
+EV_FF events are used to initialize a force feedback capable device and to cause
+such device to feedback.
+
+EV_PWR:
+----------
+EV_PWR events are a special type of event used specifically for power
+mangement. Its usage is not well defined. To be addressed later.
+
+Guidelines:
+==========
+The guidelines below ensure proper single-touch and multi-finger functionality.
+For multi-touch functionality, see the multi-touch-protocol.txt document for
+more information.
+
+Mice:
+----------
+REL_{X,Y} must be reported when the mouse moves. BTN_LEFT must be used to report
+the primary button press. BTN_{MIDDLE,RIGHT,4,5,etc.} should be used to report
+further buttons of the device. REL_WHEEL and REL_HWHEEL should be used to report
+scroll wheel events where available.
+
+Touchscreens:
+----------
+ABS_{X,Y} must be reported with the location of the touch. BTN_TOUCH must be
+used to report when a touch is active on the screen.
+BTN_{MOUSE,LEFT,MIDDLE,RIGHT} must not be reported as the result of touch
+contact. BTN_TOOL_<name> events should be reported where possible.
+
+Trackpads:
+----------
+Legacy trackpads that only provide relative position information must report
+events like mice described above.
+
+Trackpads that provide absolute touch position must report ABS_{X,Y} for the
+location of the touch. BTN_TOUCH should be used to report when a touch is active
+on the trackpad. Where multi-finger support is available, BTN_TOOL_<name> should
+be used to report the number of touches active on the trackpad.
+
+Tablets:
+----------
+BTN_TOOL_<name> events must be reported when a stylus or other tool is active on
+the tablet. ABS_{X,Y} must be reported with the location of the tool. BTN_TOUCH
+should be used to report when the tool is in contact with the tablet.
+BTN_{STYLUS,STYLUS2} should be used to report buttons on the tool itself. Any
+button may be used for buttons on the tablet except BTN_{MOUSE,LEFT}.
+BTN_{0,1,2,etc} are good generic codes for unlabeled buttons. Do not use
+meaningful buttons, like BTN_FORWARD, unless the button is labeled for that
+purpose on the device.
diff --git a/Documentation/input/joystick-parport.txt b/Documentation/input/joystick-parport.txt
index 1c856f32ff2c..56870c70a796 100644
--- a/Documentation/input/joystick-parport.txt
+++ b/Documentation/input/joystick-parport.txt
@@ -272,7 +272,7 @@ if you want to use gamecon.c.
Also, the connection is a bit more complex. You'll need a bunch of diodes,
and one pullup resistor. First, you connect the Directions and the button
-the same as for db9, however with the diodes inbetween.
+the same as for db9, however with the diodes between.
Diodes
(pin 2) -----|<|----> Up
diff --git a/Documentation/input/rotary-encoder.txt b/Documentation/input/rotary-encoder.txt
index 8b4129de1d2d..92e68bce13a4 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
@@ -46,7 +58,7 @@ c) Falling edge on channel A, channel B in high state
d) Falling edge on channel B, channel A in low state
Parking position. If the encoder enters this state, a full transition
- should have happend, unless it flipped back on half the way. The
+ should have happened, unless it flipped back on half the way. The
'armed' state tells us about that.
2. Platform requirements
@@ -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 = {
diff --git a/Documentation/input/walkera0701.txt b/Documentation/input/walkera0701.txt
index 8f4289efc5c4..561385d38482 100644
--- a/Documentation/input/walkera0701.txt
+++ b/Documentation/input/walkera0701.txt
@@ -77,7 +77,7 @@ pulse length:
24 bin+oct values + 1 bin value = 24*4+1 bits = 97 bits
-(Warning, pulses on ACK ar inverted by transistor, irq is rised up on sync
+(Warning, pulses on ACK are inverted by transistor, irq is raised up on sync
to bin change or octal value to bin change).
Binary data representations: