diff --git a/Documentation/input/event-codes.rst b/Documentation/input/event-codes.rst index 92db50954169..00b88f113bda 100644 --- a/Documentation/input/event-codes.rst +++ b/Documentation/input/event-codes.rst @@ -1,3 +1,5 @@ +.. _input-event-codes: + ================= Input event codes ================= diff --git a/Documentation/input/input.rst b/Documentation/input/input.rst index ac7669ad3e76..3b3a22975106 100644 --- a/Documentation/input/input.rst +++ b/Documentation/input/input.rst @@ -1,25 +1,20 @@ .. include:: -=================== -Linux Input drivers -=================== - -:Copyright: |copy| 1999-2001 Vojtech Pavlik - Sponsored by SuSE - -Should you need to contact me, the author, you can do so either by e-mail -- mail your message to , or by paper mail: Vojtech Pavlik, -Simunkova 1594, Prague 8, 182 00 Czech Republic - +============ 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/. +:Copyright: |copy| 1999-2001 Vojtech Pavlik - Sponsored by SuSE -The centre of the input drivers is the input module, which must be +Architecture +============ + +Input subsystem a collection of drivers that is designed to support +all input devices under Linux. Most of the drivers reside in +drivers/input, although quite a few live in drivers/hid and +drivers/platform. + +The core of the input subsystem 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: @@ -32,9 +27,9 @@ 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. +These modules get events from input core 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 ============ @@ -45,19 +40,18 @@ kernel):: input mousedev - keybdev usbcore uhci_hcd or ohci_hcd or ehci_hcd usbhid + hid_generic 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:: +This device usually created automatically by the system. The commands +to create it by hand are:: cd /dev mkdir input @@ -81,19 +75,110 @@ When you do all of the above, you can use your USB mouse and keyboard. Detailed Description ==================== +Event handlers +-------------- + +Event handlers distribute the events from the devices to userspace and +in-kernel consumers, as needed. + +evdev +~~~~~ + +``evdev`` is the generic input event interface. It passes the events +generated in the kernel straight to the program, with timestamps. The +event codes are the same on all architectures and are hardware +independent. + +This is the preferred interface for userspace to consume user +input, and all clients are encouraged to use it. + +See :ref:`event-interface` for notes on API. + +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 + ... + +There are two ranges of minors: 64 through 95 is the static legacy +range. If there are more than 32 input devices in a system, additional +evdev nodes are created with minors starting with 256. + +keyboard +~~~~~~~~ + +``keyboard`` is in-kernel input handler ad is a part of VT code. It +consumes keyboard keystrokes and handles user input for VT consoles. + +mousedev +~~~~~~~~ + +``mousedev`` is a hack to make legacy 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. + +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 older programs +that do not handle hotplug 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. See +:ref:`joystick-api` 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 in legacy range, and additional nodes with minors +above 256 if there are more joystick devices. + 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. +Device drivers are the modules that generate events. -usbhid -~~~~~~ +hid-generic +~~~~~~~~~~~ -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. +``hid-generic`` is one of 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. @@ -131,145 +216,47 @@ 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 +psmouse +~~~~~~~ + +This is driver for all flavors of pointing devices using PS/2 +protocol, including Synaptics and ALPS touchpads, Intellimouse +Explorer devices, Logitech PS/2 mice and so on. + +atkbd ~~~~~ -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. +This is driver for PS/2 (AT) keyboards. iforce ~~~~~~ A driver for I-Force joysticks and wheels, both over USB and RS232. -It includes ForceFeedback support now, even though Immersion +It includes Force Feedback 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 +a 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). +available in the joystick package (see :ref:`joystick-doc`). -You can test the event devices with the ``evtest`` utility available -in the LinuxConsole project CVS archive (see the URL below). +You can test the event devices with the ``evtest`` utility. + +.. _event-interface: Event interface =============== -Should you want to add event device support into any application (X, gpm, -svgalib ...) I 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 +You can use blocking and nonblocking reads, and 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:: @@ -290,3 +277,5 @@ 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. + +See :ref:`input-event-codes` for more information about various even codes. diff --git a/Documentation/input/joydev/joystick-api.rst b/Documentation/input/joydev/joystick-api.rst index 42edcfc6e8af..95803e2e8cd0 100644 --- a/Documentation/input/joydev/joystick-api.rst +++ b/Documentation/input/joydev/joystick-api.rst @@ -1,3 +1,5 @@ +.. _joystick-api: + ===================== Programming Interface ===================== diff --git a/Documentation/input/joydev/joystick.rst b/Documentation/input/joydev/joystick.rst index b90705eb69b1..9746fd76cc58 100644 --- a/Documentation/input/joydev/joystick.rst +++ b/Documentation/input/joydev/joystick.rst @@ -1,5 +1,7 @@ .. include:: +.. _joystick-doc: + Introduction ============