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diff --git a/Documentation/input/input.txt b/Documentation/input/input.txt deleted file mode 100644 index fda995e0ceb0..000000000000 --- a/Documentation/input/input.txt +++ /dev/null @@ -1,312 +0,0 @@ -.. include:: <isonum.txt> - -=================== -Linux Input drivers -=================== - -:Copyright: |copy| 1999-2001 Vojtech Pavlik <vojtech@ucw.cz> - Sponsored by SuSE - -Disclaimer -========== - -This program is free software; you can redistribute it and/or modify it -under the terms of the GNU General Public License as published by the Free -Software Foundation; either version 2 of the License, or (at your option) -any later version. - -This program is distributed in the hope that it will be useful, but -WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for -more details. - -You should have received a copy of the GNU General Public License along -with this program; if not, write to the Free Software Foundation, Inc., 59 -Temple Place, Suite 330, Boston, MA 02111-1307 USA - -Should you need to contact me, the author, you can do so either by e-mail -- mail your message to <vojtech@ucw.cz>, or by paper mail: Vojtech Pavlik, -Simunkova 1594, Prague 8, 182 00 Czech Republic - -For your convenience, the GNU General Public License version 2 is included -in the package: See the file COPYING. - -Introduction -============ - -This is a collection of drivers that is designed to support all input -devices under Linux. While it is currently used only on for USB input -devices, future use (say 2.5/2.6) is expected to expand to replace -most of the existing input system, which is why it lives in -drivers/input/ instead of drivers/usb/. - -The centre of the input drivers is the input module, which must be -loaded before any other of the input modules - it serves as a way of -communication between two groups of modules: - -Device drivers --------------- - -These modules talk to the hardware (for example via USB), and provide -events (keystrokes, mouse movements) to the input module. - -Event handlers --------------- - -These modules get events from input and pass them where needed via -various interfaces - keystrokes to the kernel, mouse movements via a -simulated PS/2 interface to GPM and X and so on. - -Simple Usage -============ - -For the most usual configuration, with one USB mouse and one USB keyboard, -you'll have to load the following modules (or have them built in to the -kernel):: - - input - mousedev - keybdev - usbcore - uhci_hcd or ohci_hcd or ehci_hcd - usbhid - -After this, the USB keyboard will work straight away, and the USB mouse -will be available as a character device on major 13, minor 63:: - - crw-r--r-- 1 root root 13, 63 Mar 28 22:45 mice - -This device has to be created. - -The commands to create it by hand are:: - - cd /dev - mkdir input - mknod input/mice c 13 63 - -After that you have to point GPM (the textmode mouse cut&paste tool) and -XFree to this device to use it - GPM should be called like:: - - gpm -t ps2 -m /dev/input/mice - -And in X:: - - Section "Pointer" - Protocol "ImPS/2" - Device "/dev/input/mice" - ZAxisMapping 4 5 - EndSection - -When you do all of the above, you can use your USB mouse and keyboard. - -Detailed Description -==================== - -Device drivers --------------- - -Device drivers are the modules that generate events. The events are -however not useful without being handled, so you also will need to use some -of the modules from section 3.2. - -usbhid -~~~~~~ - -usbhid is the largest and most complex driver of the whole suite. It -handles all HID devices, and because there is a very wide variety of them, -and because the USB HID specification isn't simple, it needs to be this big. - -Currently, it handles USB mice, joysticks, gamepads, steering wheels -keyboards, trackballs and digitizers. - -However, USB uses HID also for monitor controls, speaker controls, UPSs, -LCDs and many other purposes. - -The monitor and speaker controls should be easy to add to the hid/input -interface, but for the UPSs and LCDs it doesn't make much sense. For this, -the hiddev interface was designed. See Documentation/hid/hiddev.txt -for more information about it. - -The usage of the usbhid module is very simple, it takes no parameters, -detects everything automatically and when a HID device is inserted, it -detects it appropriately. - -However, because the devices vary wildly, you might happen to have a -device that doesn't work well. In that case #define DEBUG at the beginning -of hid-core.c and send me the syslog traces. - -usbmouse -~~~~~~~~ - -For embedded systems, for mice with broken HID descriptors and just any -other use when the big usbhid wouldn't be a good choice, there is the -usbmouse driver. It handles USB mice only. It uses a simpler HIDBP -protocol. This also means the mice must support this simpler protocol. Not -all do. If you don't have any strong reason to use this module, use usbhid -instead. - -usbkbd -~~~~~~ - -Much like usbmouse, this module talks to keyboards with a simplified -HIDBP protocol. It's smaller, but doesn't support any extra special keys. -Use usbhid instead if there isn't any special reason to use this. - -wacom -~~~~~ - -This is a driver for Wacom Graphire and Intuos tablets. Not for Wacom -PenPartner, that one is handled by the HID driver. Although the Intuos and -Graphire tablets claim that they are HID tablets as well, they are not and -thus need this specific driver. - -iforce -~~~~~~ - -A driver for I-Force joysticks and wheels, both over USB and RS232. -It includes ForceFeedback support now, even though Immersion -Corp. considers the protocol a trade secret and won't disclose a word -about it. - -Event handlers --------------- - -Event handlers distribute the events from the devices to userland and -kernel, as needed. - -keybdev -~~~~~~~ - -keybdev is currently a rather ugly hack that translates the input -events into architecture-specific keyboard raw mode (Xlated AT Set2 on -x86), and passes them into the handle_scancode function of the -keyboard.c module. This works well enough on all architectures that -keybdev can generate rawmode on, other architectures can be added to -it. - -The right way would be to pass the events to keyboard.c directly, -best if keyboard.c would itself be an event handler. This is done in -the input patch, available on the webpage mentioned below. - -mousedev -~~~~~~~~ - -mousedev is also a hack to make programs that use mouse input -work. It takes events from either mice or digitizers/tablets and makes -a PS/2-style (a la /dev/psaux) mouse device available to the -userland. Ideally, the programs could use a more reasonable interface, -for example evdev - -Mousedev devices in /dev/input (as shown above) are:: - - crw-r--r-- 1 root root 13, 32 Mar 28 22:45 mouse0 - crw-r--r-- 1 root root 13, 33 Mar 29 00:41 mouse1 - crw-r--r-- 1 root root 13, 34 Mar 29 00:41 mouse2 - crw-r--r-- 1 root root 13, 35 Apr 1 10:50 mouse3 - ... - ... - crw-r--r-- 1 root root 13, 62 Apr 1 10:50 mouse30 - crw-r--r-- 1 root root 13, 63 Apr 1 10:50 mice - -Each ``mouse`` device is assigned to a single mouse or digitizer, except -the last one - ``mice``. This single character device is shared by all -mice and digitizers, and even if none are connected, the device is -present. This is useful for hotplugging USB mice, so that programs -can open the device even when no mice are present. - -CONFIG_INPUT_MOUSEDEV_SCREEN_[XY] in the kernel configuration are -the size of your screen (in pixels) in XFree86. This is needed if you -want to use your digitizer in X, because its movement is sent to X -via a virtual PS/2 mouse and thus needs to be scaled -accordingly. These values won't be used if you use a mouse only. - -Mousedev will generate either PS/2, ImPS/2 (Microsoft IntelliMouse) or -ExplorerPS/2 (IntelliMouse Explorer) protocols, depending on what the -program reading the data wishes. You can set GPM and X to any of -these. You'll need ImPS/2 if you want to make use of a wheel on a USB -mouse and ExplorerPS/2 if you want to use extra (up to 5) buttons. - -joydev -~~~~~~ - -Joydev implements v0.x and v1.x Linux joystick api, much like -drivers/char/joystick/joystick.c used to in earlier versions. See -joystick-api.txt in the Documentation subdirectory for details. As -soon as any joystick is connected, it can be accessed in /dev/input -on:: - - crw-r--r-- 1 root root 13, 0 Apr 1 10:50 js0 - crw-r--r-- 1 root root 13, 1 Apr 1 10:50 js1 - crw-r--r-- 1 root root 13, 2 Apr 1 10:50 js2 - crw-r--r-- 1 root root 13, 3 Apr 1 10:50 js3 - ... - -And so on up to js31. - -evdev -~~~~~ - -evdev is the generic input event interface. It passes the events -generated in the kernel straight to the program, with timestamps. The -API is still evolving, but should be usable now. It's described in -section 5. - -This should be the way for GPM and X to get keyboard and mouse -events. It allows for multihead in X without any specific multihead -kernel support. The event codes are the same on all architectures and -are hardware independent. - -The devices are in /dev/input:: - - crw-r--r-- 1 root root 13, 64 Apr 1 10:49 event0 - crw-r--r-- 1 root root 13, 65 Apr 1 10:50 event1 - crw-r--r-- 1 root root 13, 66 Apr 1 10:50 event2 - crw-r--r-- 1 root root 13, 67 Apr 1 10:50 event3 - ... - -And so on up to event31. - -Verifying if it works -===================== - -Typing a couple keys on the keyboard should be enough to check that -a USB keyboard works and is correctly connected to the kernel keyboard -driver. - -Doing a ``cat /dev/input/mouse0`` (c, 13, 32) will verify that a mouse -is also emulated; characters should appear if you move it. - -You can test the joystick emulation with the ``jstest`` utility, -available in the joystick package (see Documentation/input/joystick.txt). - -You can test the event devices with the ``evtest`` utility available -in the LinuxConsole project CVS archive (see the URL below). - -Event interface -=============== - -Should you want to add event device support into any application (X, gpm, -svgalib ...) I <vojtech@ucw.cz> will be happy to provide you any help I -can. Here goes a description of the current state of things, which is going -to be extended, but not changed incompatibly as time goes: - -You can use blocking and nonblocking reads, also select() on the -/dev/input/eventX devices, and you'll always get a whole number of input -events on a read. Their layout is:: - - struct input_event { - struct timeval time; - unsigned short type; - unsigned short code; - unsigned int value; - }; - -``time`` is the timestamp, it returns the time at which the event happened. -Type is for example EV_REL for relative moment, EV_KEY for a keypress or -release. More types are defined in include/uapi/linux/input-event-codes.h. - -``code`` is event code, for example REL_X or KEY_BACKSPACE, again a complete -list is in include/uapi/linux/input-event-codes.h. - -``value`` is the value the event carries. Either a relative change for -EV_REL, absolute new value for EV_ABS (joysticks ...), or 0 for EV_KEY for -release, 1 for keypress and 2 for autorepeat. |