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EVDEV

Section: Devices and Network Interfaces (4)
Updated: xf86-input-evdev 1.2.0
Index Return to Main Contents
 

NAME

evdev - Generic Linux input driver  

SYNOPSIS

Section N'34'InputDeviceN'34'
  Identifier N'34'devnameN'34'
  Driver N'34'evdevN'34'
  Option N'34'DeviceN'34'   N'34'devpathN'34'
  ...
EndSection
 

DESCRIPTION

evdev is an Xorg input driver for Linux's generic event devices. It therefore supports all input devices that the kernel knows about, including most mice and keyboards.

The evdev driver can serve as both a pointer and a keyboard input device, and may be used as both the core keyboard and the core pointer. Multiple input devices are supported by multiple instances of this driver, with one Load directive for evdev in the Module section of your xorg.conf for each input device that will use this driver.

 

SUPPORTED HARDWARE

In general, any input device that the kernel has a driver for can be accessed through the evdev driver. See the Linux kernel documentation for a complete list.

 

CONFIGURATION DETAILS

Please refer to xorg.conf(5) for general configuration details and for options that can be used with all input drivers. This section only covers configuration details specific to this driver.

 

BASIC CONFIGURATIONS

Most users of this driver will probably be quite happy with the following for all QWERTY keyboards:

Section N'34'InputDeviceN'34'
  Identifier N'34'keyboardN'34'
  Driver N'34'evdevN'34'
  Option N'34'evBitsN'34'  N'34'+1N'34'
  Option N'34'keyBitsN'34' N'34'~1-255 ~352-511N'34'
  Option N'34'PassN'34'    N'34'3N'34'
  ...
EndSection

And the following for all mice:

Section N'34'InputDeviceN'34'
  Identifier N'34'mouseN'34'
  Driver N'34'evdevN'34'
  Option N'34'evBitsN'34'  N'34'+1-2N'34'
  Option N'34'keyBitsN'34' N'34'~272-287N'34'
  Option N'34'relBitsN'34' N'34'~0-2 ~6 ~8N'34'
  Option N'34'PassN'34'    N'34'3N'34'
  ...
EndSection

To understand what those Bits options do, or for more complex configurations, please see ADVANCED OPTIONS below.

 

ADVANCED OPTIONS

 

DEVICE SPECIFICATION

For this section you'll want to have knowledge of glob (7) and our evil BIT MATCHING SPECIFICATION stuff.

The following driver Options control what devices are accepted:

Option N'34'DeviceN'34' N'34'stringN'34'
Specifies the device note through which the device can be accessed. At this time ONLY /dev/input/eventn, where n is an integer, are matched against this this field. This option uses globbing. Please note that use of this option is strongly discouraged.

Option N'34'NameN'34' N'34'stringN'34'
Specifies the device name for the device you wish to use. The device name is generally the only consistent identifier for devices that are commonly unplugged and plugged back into different ports. A list of currently plugged in devices and associated device names can be obtained by typing N'34'cat /proc/bus/input/devicesN'34', the N'34'NameN'34' field is the value you want for this option. This option uses globbing.

Option N'34'PhysN'34' N'34'stringN'34'
Specifies the device phys string for the device you wish to use. The phys string is generally consistent to the USB port a device is plugged into. A list of currently plugged in devices and associated device names can be obtained by typing N'34'cat /proc/bus/input/devicesN'34', the N'34'PhysN'34' field is the value you want for this option. This option uses globbing.

Option N'34'mapBitsN'34' N'34'bit specifierN'34'
Specifies device capability bits which must be set, possibly set, or unset. mapBits: Where map is one of ev, key, rel, abs, msc, led, snd, or ff. The bit specifier format is a string consisting of +n, -n, and ~n space-separated specifiers, where n is a positive integer or integer range. (The latter given in the format of 2-6.) + specifies bits which must be set. - specifies bits which must not be set. ~ is a little more complex, it specifies that at least one of the bits given with ~ for the field in question must be set, but it doesn't matter how many or which of the bits. (It is actually the most useful of the 3 specifiers.) As an example, N'34'+0 +3 -1-2 ~5-10N'34' requires bits 0 and 3 be set, bits 1 and 2 to not be set, and at least one bit in the range of 5 to 10 be set. An annoyingly formatted set of bitmasks for your devices can be obtained by typing N'34'cat /proc/bus/input/devicesN'34', and /usr/include/linux/input.h should contain the defines which declare what bits are what for each field.

Option N'34'bustypeN'34' N'34'nN'34'
Specifies the bus ID for the device you wish to use. This is either 0 (the default, matches anything), or the Bus=n field in /proc/bus/input/devices for your device. This value depends on what type of bus your device is connected to.

Option N'34'vendorN'34' N'34'nN'34'
Specifies the vendor ID for the device you wish to use. This is either 0 (the default, matches anything), or the Vendor=n field in /proc/bus/input/devices for your device. This value should remain constant barring perhaps firmware updates to the device itself.

Option N'34'versionN'34' N'34'nN'34'
Specifies the version for the device you wish to use. This is either 0 (the default, matches anything), or the Version=n field in /proc/bus/input/devices for your device. This value should remain constant barring perhaps firmware updates to the device itself.

Option N'34'productN'34' N'34'nN'34'
Specifies the product ID for the device you wish to use. This is either 0 (the default, matches anything), or the Product=n field in /proc/bus/input/devices for your device. This value should remain constant barring perhaps firmware updates to the device itself.

Option N'34'PassN'34' N'34'nN'34'
Specifies the order in which evdev will scan for devices. This is in the range of 0 to 3, and is used for the case where more then one evdev input section matches the same device. An input section with a lower pass number will always beat out one with a higher pass number. Order when both sections are the same number is undefined. The default is 0.

 

RELATIVE AXIS CONFIGURATION

The relative axis portion of this driver handle all reported relative axes. The axes are named X, Y, Z, RX, RY, RZ, HWHEEL, DIAL, WHEEL, MISC, 10, 11, 12, 13, 14, and 15. The axes are reported to X as valuators, with the default mapping of axes to valuators being the first axes found to the first valuator, the second found to the second valuator, and so on, so that if you have axes X, Y, HWHEEL, and WHEEL, you would have X=0, Y=1, HWHEEL=2, WHEEL=3. If the driver is reporting core events, valuators 0 and 1 are always mapped to x and y coordinates, respectively. The following driver Options control the relative axis portion of the driver:
Option N'34'axisRelativeAxisMapN'34' N'34'nN'34'
This remaps the axis specified to the specified valuator.
Option N'34'axisRelativeAxisButtonsN'34' N'34'n nN'34'
This remaps the axis specified to the specified buttons. Note that the physical buttons are always remapped around N'34'fakeN'34' buttons created by this option, so that if you have physical buttons 1 2 3 4 5, and map the Wheel axis to buttons 4 5, you get buttons 1 2 3 4 5 6 7, with buttons 6 and 7 being physical buttons 4 and 5.

 

ABSOLUTE AXIS CONFIGURATION

The relative axis portion of this driver handle all reported relative axes. The axes are named X, Y, Z, RX, RY, RZ, THROTTLE, RUDDER, WHEEL, GAS, BRAKE, <11-15>, HAT0X, HAT0Y, HAT1X, HAT1Y, HAT2X, HAT2Y, HAT3X, HAT3Y, PRESSURE, TILT_X, TILT_Y, TOOL_WIDTH, VOLUME, <29-39>, MISC, <41-62>. The axes are reported to X as valuators, with the default mapping of axes to valuators being the first axes found to the first valuator, the second found to the second valuator, and so on, so that if you have axes X, Y, TILT_X, and TILT_Y, you would have X=0, Y=1, TILT_X=2, TILT_Y=3. If the driver is reporting core events, valuators 0 and 1 are always mapped to x and y coordinates, respectively. The following driver Options control the relative axis portion of the driver:
Option N'34'axisAbsoluteAxisMapN'34' N'34'nN'34'
This remaps the axis specified to the specified valuator.
Option N'34'AbsoluteScreenN'34' N'34'nN'34'
This binds the device to a specific screen, scaling it to the coordinate space of that screen. The number can either be -1, or a valid screen number. If -1 or if in relative mode no scaling or screen fixing is done. This is of most use for digitizers, where the screen and the input device are the same surface.
Option N'34'ModeN'34' N'34'modeN'34'
This selects the default mode for the device. Valid values are N'34'absoluteN'34' and N'34'relativeN'34'. This can be set at run time per actual device with the xinput utility.

 

BUTTON CONFIGURATION

At the moment, the button portion of this driver only handles buttons reported as mouse buttons, that is from BTN_MOUSE to BTN_JOYSTICK - 1. At this time there are no configuration options for buttons.  

KEYBOARD CONFIGURATION

The keyboard portion of this driver handles all keys reported and requires XKB support. The following driver Options control the relative axis portion of the driver:
Option N'34'XkbRulesN'34' N'34'rulesN'34'
specifies which XKB rules file to use for interpreting the XkbModel, XkbLayout, XkbVariant, and XkbOptions settings. Default: N'34'xorgN'34' for most platforms, but N'34'xfree98N'34' for the Japanese PC-98 platforms.
Option N'34'XkbModelN'34' N'34'modelnameN'34'
specifies the XKB keyboard model name. Default: N'34'evdevN'34'.
Option N'34'XkbLayoutN'34' N'34'layoutnameN'34'
specifies the XKB keyboard layout name. This is usually the country or language type of the keyboard. Default: N'34'usN'34'.
Option N'34'XkbVariantN'34' N'34'variantsN'34'
specifies the XKB keyboard variant components. These can be used to enhance the keyboard layout details. Default: not set.
Option N'34'XkbOptionsN'34' N'34'optionsN'34'
specifies the XKB keyboard option components. These can be used to enhance the keyboard behaviour. Default: not set.

 

AUTHORS

Zephaniah E. Hull. Kristian H/ogsberg.  

SEE ALSO

Xorg(1), xorg.conf(5), xorgconfig(1), Xserver(1), X(7).


 

Index

NAME
SYNOPSIS
DESCRIPTION
SUPPORTED HARDWARE
CONFIGURATION DETAILS
BASIC CONFIGURATIONS
ADVANCED OPTIONS
DEVICE SPECIFICATION
RELATIVE AXIS CONFIGURATION
ABSOLUTE AXIS CONFIGURATION
BUTTON CONFIGURATION
KEYBOARD CONFIGURATION
AUTHORS
SEE ALSO




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