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.\"     $NetBSD: wskbd.9,v 1.15 2010/12/02 12:54:13 wiz Exp $
.\"
.\" Copyright (c) 2001 The NetBSD Foundation, Inc.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to The NetBSD Foundation
.\" by Gregory McGarry.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
.\" PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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.\"
.Dd December 20, 2005
.Dt WSKBD 9
.Os
.Sh NAME
.Nm wskbd ,
.Nm wskbd_input ,
.Nm wskbd_rawinput ,
.Nm wskbd_cnattach ,
.Nm wskbd_cndetach ,
.Nm wskbddevprint
.Nd wscons keyboard support
.Sh SYNOPSIS
.In dev/wscons/wsconsio.h
.In dev/wscons/wskbdvar.h
.In dev/wscons/wsksymdef.h
.In dev/wscons/wsksymvar.h
.Ft void
.Fn wskbd_input "struct device *kbddev" "u_int type" "int value"
.Ft void
.Fn wskbd_rawinput "struct device *kbddev" "u_char *buf" "int len"
.Ft void
.Fn wskbd_cnattach "const struct wskbd_consops *consops" "void *conscookie" \
"const struct wskbd_mapdata *mapdata"
.Ft void
.Fn wskbd_cndetach ""
.Ft int
.Fn wskbddevprint "void *aux" "const char *pnp"
.Sh DESCRIPTION
The
.Nm
module is a component of the
.Xr wscons 9
framework to provide machine-independent keyboard support.
Most of the support is provided by the
.Xr wskbd 4
device driver, which must be a child of the hardware device driver.
.Sh DATA TYPES
Keyboard drivers providing support for wscons keyboards will make use
of the following data types:
.Bl -tag -width compact
.It Fa kbd_t
An opaque type describing keyboard properties.
.It Fa keysym_t
The wscons keyboard-independent symbolic representation of the keypress.
.It Fa struct wskbd_accessops
A structure used to specify the keyboard access functions.
All keyboards must provide this structure and pass it to the
.Xr wskbd 4
child device.
It has the following members:
.Bd -literal
	int	(*enable)(void *, int);
	void	(*set_leds)(void *, int);
	int	(*ioctl)(void *v, u_long cmd, void *data,
			int flag, struct lwp *l);
.Ed
.Pp
The
.Fa enable
member defines the function to be called to enable keypress passing to
wscons.
The
.Fa set_leds
member defined the function to be called to set the LEDs on the
keyboard.
The
.Fa ioctl
member defines the function to be called to perform keyboard-specific
ioctl calls.
.Pp
There is a
.Fa void *
cookie provided by the keyboard driver associated with these
functions, which is passed to them when they are invoked.
.It Fa struct wskbd_consops
A structure used to specify the keyboard console operations.
All keyboards which can operate as a console must provide this structure
and pass it to the
.Xr wskbd 4
child device.
If the keyboard cannot be a console, it is not
necessary to specify this structure.
It has the following members:
.Bd -literal
	void	(*getc)(void *, u_int *, int *);
	void	(*pollc)(void *, int);
	void	(*bell)(void *, u_int, u_int, u_int);
.Ed
.Pp
There is a
.Fa void *
cookie provided by the keyboard driver associated with these
functions, which is passed to them when they are invoked.
.It Fa struct wscons_keydesc
A structure used to describe a keyboard mapping table to convert
keyboard-specific keycodes to wscons keysyms.
It has the
following members:
.Bd -literal
	kbd_t	name;		/* name of this map */
	kbd_t	base;		/* map this one is based on */
	int	map_size;	/* size of map */
	const	keysym_t *map;	/* the map itself */
.Ed
.It Fa struct wskbd_mapdata
A structure used to describe the keyboard layout and operation to
interpret the keyboard layout.
it contains the following members:
.Bd -literal
        const struct wscons_keydesc *keydesc;
        kbd_t layout;
.Ed
.It Fa struct wskbddev_attach_args
A structure used to attach the
.Xr wskbd 4
child device.
It has the following members:
.Bd -literal
	int console;
	const struct wskbd_mapdata *keymap;
	const struct wskbd_accessops *accessops;
	void *accesscookie;
.Ed
.El
.Ss Keymaps
Keymaps are a dense stream of
.Fa keysym_t .
A declaration has the following fields:
.Pp
.Ar pos
.Op Ar cmd
.Ar normal
.Op Ar shift
.Op Ar altgr
.Op Ar shift-altgr
.Pp
The fields have the following meanings:
.Pp
.Bl -tag -offset indent -width SHIFT-ALTGR -compact
.It Ar pos
Always specified as
.Ns KC( Ns Ar pos )
and starts the description of key
.Ar pos .
.It Ar cmd
If the command modifier (KS_Cmd_XXX) is active, the optional command
.Ar cmd
is invoked.
.It Ar normal
The keysym if no modifiers are active.
.It Ar shift
The keysym if the shift modifier is active.
.It Ar altgr
The keysym if the alt-gr modifier is active.
.It Ar shift-altgr
The keysym if the shift-alt-gr modifier is active.
.El
.Pp
If the keysym after
.Ar pos
is not KS_Cmd_XXX, then
.Ar cmd
is empty.
The
.Ar shift ,
.Ar altgr
and
.Ar shift-altgr
fields are determined from previous fields if they are not specified.
Therefore, there are four valid keysym declarations:
.Pp
.Ar pos
.Op Ar cmd
.Ar normal
.Pp
.Ar pos
.Op Ar cmd
.Ar normal Ar shift
.Pp
.Ar pos
.Op Ar cmd
.Ar normal Ar shift Ar altgr
.Pp
.Ar pos
.Op Ar cmd
.Ar normal Ar shift Ar altgr Ar shift-altgr
.Sh FUNCTIONS
.Bl -tag -width compact
.It Fn wskbd_input "kbddev" "type" "value"
Pass the keypress of value
.Fa value
and type
.Fa type
to wscons keyboard driver.
Valid values of
.Fa type
are:
.Bl -tag -width compact
.It WSCONS_EVENT_KEY_UP
Key released.
.It WSCONS_EVENT_KEY_DOWN
Key pressed.
.El
.It Fn wskbd_rawinput "kbddev" "buf" "len"
Pass the raw keypress in the buffer
.Fa buf
to the wscons keyboard driver.
The buffer is
.Fa len
bytes long.
This function should only be called if the kernel option
.Em WSDISPLAY_COMPAT_RAWKBD
is enabled.
.It Fn wskbd_cnattach "consops" "conscookie" "mapdata"
Attach this keyboard as the console input by specifying the console
operations
.Fa consops
and the keyboard mapping table information in
.Fa mapdata .
The functions specified in
.Fa consops
will be called with
.Fa conscookie
as the first argument.
.It Fn wskbd_cndetach ""
Detach this keyboard as the console input.
.It Fn wskbddevprint "aux" "pnp"
The default wskbd printing routine used by
.Fn config_found .
(see
.Xr autoconf 9 ) .
.El
.Sh AUTOCONFIGURATION
Keyboard drivers which want to use the wskbd module must be a
parent to the
.Xr wskbd 4
device and provide an attachment interface.
To attach the
.Xr wskbd 4
device, the keyboard driver must allocate and populate a
.Fa wskbddev_attach_args
structure with the supported operations and callbacks and call
.Fn config_found
to perform the attach (see
.Xr autoconf 9 ) .
The
.Fa keymap
member points to the
.Em wskbd_mapdata
structure which describes the keycode mapping operations.
The
.Fa accessops
member points to the
.Em wskbd_accessops
structure which describes the keyboard access operations.
The
.Fa console
member is a boolean to indicate to wscons whether this keyboard will
be used for console input.
.Sh OPERATION
If the keyboard belongs to the system console, it must register the
.Fa wskbd_consops
structure specifying the console operations via
.Fn wskbd_cnattach
at console attach time.
.Pp
When a keypress arrives from the keyboard, the keyboard driver must
perform any necessary character decoding to wscons events and pass the
events to wscons via
.Fn wskbd_input .
If the kernel is compiled with the option
.Em WSDISPLAY_COMPAT_RAWKBD ,
then the keyboard driver must also pass the raw keyboard data to
wscons via
.Fn wskbd_rawinput .
.Pp
The wscons framework calls back into the hardware driver by invoking
the functions that are specified in the
.Em accessops
structure.
The
.Fn enable
and
.Fn set_leds
functions are relatively simple and self-explanatory.
The
.Fn ioctl
function is called by the wscons interface to perform
keyboard-specific ioctl operations (see
.Xr ioctl 2 ) .
The argument
.Fa cmd
to the
.Fn ioctl
function specifies the specific command to perform using the data
.Fa data .
Valid commands are listed in
.Pa sys/dev/wscons/wsconsio.h .
.Sh CODE REFERENCES
The wscons subsystem is implemented within the directory
.Pa sys/dev/wscons .
The
.Nm
module itself is implement within the files
.Pa sys/dev/wscons/wskbd.c
and
.Pa sys/dev/wscons/wskbdutil.c .
.Xr ioctl 2
operations are listed in
.Pa sys/dev/wscons/wsconsio.h .
.Sh SEE ALSO
.Xr ioctl 2 ,
.Xr autoconf 9 ,
.Xr driver 9 ,
.Xr intro 9 ,
.Xr wsdisplay 9 ,
.Xr wsmouse 9