/*-
 * (MPSAFE)
 *
 * Copyright (c) 2005 Maksim Yevmenkin <m_evmenkin@yahoo.com>
 * All rights reserved.
 *
 * 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 AUTHOR 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 AUTHOR 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 INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $Id: kbdmux.c,v 1.4 2005/07/14 17:38:35 max Exp $
 * $FreeBSD$
 */

#include "opt_evdev.h"
#include "opt_kbd.h"

#include <sys/param.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <sys/consio.h>
#include <sys/fcntl.h>
#include <sys/kbio.h>
#include <sys/kernel.h>
#include <sys/limits.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/poll.h>
#include <sys/proc.h>
#include <sys/queue.h>
#include <sys/event.h>
#include <sys/systm.h>
#include <sys/taskqueue.h>
#include <sys/uio.h>
#include <dev/misc/kbd/kbdreg.h>
#include <dev/misc/kbd/kbdtables.h>

#ifdef EVDEV_SUPPORT
#include <dev/misc/evdev/evdev.h>
#include <dev/misc/evdev/input.h>
#endif

#define KEYBOARD_NAME   "kbdmux"

MALLOC_DECLARE(M_KBDMUX);
MALLOC_DEFINE(M_KBDMUX, KEYBOARD_NAME, "Keyboard multiplexor");

/*****************************************************************************
 *****************************************************************************
 **                             Keyboard state
 *****************************************************************************
 *****************************************************************************/

#define KBDMUX_Q_SIZE   512     /* input queue size */

/*
 * kbdmux keyboard
 */
struct kbdmux_kbd
{
        keyboard_t              *kbd;   /* keyboard */
        SLIST_ENTRY(kbdmux_kbd)  next;  /* link to next */
};

typedef struct kbdmux_kbd       kbdmux_kbd_t;

/*
 * kbdmux state
 */
struct kbdmux_state
{
        char                     ks_inq[KBDMUX_Q_SIZE]; /* input chars queue */
        unsigned int             ks_inq_start;
        unsigned int             ks_inq_length;
        struct task              ks_task;       /* interrupt task */

        int                      ks_flags;      /* flags */
#define COMPOSE                 (1 << 0)        /* compose char flag */
#define POLLING                 (1 << 1)        /* polling */

        int                      ks_mode;       /* K_XLATE, K_RAW, K_CODE */
        int                      ks_state;      /* state */
        int                      ks_accents;    /* accent key index (> 0) */
        u_int                    ks_composed_char; /* composed char code */
        u_char                   ks_prefix;     /* AT scan code prefix */

#ifdef EVDEV_SUPPORT
        struct evdev_dev *       ks_evdev;
        int                      ks_evdev_state;
#endif

        SLIST_HEAD(, kbdmux_kbd) ks_kbds;       /* keyboards */
};

typedef struct kbdmux_state     kbdmux_state_t;

/*****************************************************************************
 *****************************************************************************
 **                             Helper functions
 *****************************************************************************
 *****************************************************************************/

static task_fn_t                kbdmux_kbd_intr;
static kbd_callback_func_t      kbdmux_kbd_event;

static void
kbdmux_kbd_putc(kbdmux_state_t *state, char c)
{
        unsigned int p;

        if (state->ks_inq_length == KBDMUX_Q_SIZE)
                return;

        p = (state->ks_inq_start + state->ks_inq_length) % KBDMUX_Q_SIZE;
        state->ks_inq[p] = c;
        state->ks_inq_length++;
}

static int
kbdmux_kbd_getc(kbdmux_state_t *state)
{
        unsigned char c;

        if (state->ks_inq_length == 0)
                return (-1);

        c = state->ks_inq[state->ks_inq_start];
        state->ks_inq_start = (state->ks_inq_start + 1) % KBDMUX_Q_SIZE;
        state->ks_inq_length--;

        return (c);
}

/*
 * Interrupt handler task
 */
static void
kbdmux_kbd_intr(void *xkbd, int pending)
{
        keyboard_t      *kbd = (keyboard_t *) xkbd;
        KBD_LOCK_DECLARE;

        KBD_LOCK(kbd);          /* recursive so ok */
        kbd_intr(kbd, NULL);
        KBD_UNLOCK(kbd);
}

/*
 * Process event from one of our keyboards
 */
static int
kbdmux_kbd_event(keyboard_t *kbd, int event, void *arg)
{
        kbdmux_state_t  *state = (kbdmux_state_t *) arg;

        switch (event) {
        case KBDIO_KEYINPUT: {
                int     c;

                /*
                 * Read all chars from the keyboard
                 *
                 * Turns out that atkbd(4) check_char() method may return
                 * "true" while read_char() method returns NOKEY. If this
                 * happens we could stuck in the loop below. Avoid this
                 * by breaking out of the loop if read_char() method returns
                 * NOKEY.
                 */

                while (kbd_check_char(kbd)) {
                        c = kbd_read_char(kbd, 0);
                        if (c == NOKEY)
                                break;
                        if (c == ERRKEY)
                                continue; /* XXX ring bell */
                        if (!KBD_IS_BUSY(kbd))
                                continue; /* not open - discard the input */

                        kbdmux_kbd_putc(state, c);
                }

                /* queue interrupt task if needed */
                if (state->ks_inq_length > 0)
                        taskqueue_enqueue(taskqueue_swi, &state->ks_task);

                } break;

        case KBDIO_UNLOADING: {
                kbdmux_kbd_t    *k;

                SLIST_FOREACH(k, &state->ks_kbds, next)
                        if (k->kbd == kbd)
                                break;

                if (k != NULL) {
                        kbd_release(k->kbd, &k->kbd);
                        SLIST_REMOVE(&state->ks_kbds, k, kbdmux_kbd, next);

                        k->kbd = NULL;

                        kfree(k, M_KBDMUX);
                }

                } break;

        default:
                return (EINVAL);
                /* NOT REACHED */
        }
        return (0);
}

/****************************************************************************
 ****************************************************************************
 **                              Keyboard driver
 ****************************************************************************
 ****************************************************************************/

static int              kbdmux_configure(int flags);
static kbd_probe_t      kbdmux_probe;
static kbd_init_t       kbdmux_init;
static kbd_term_t       kbdmux_term;
static kbd_intr_t       kbdmux_intr;
static kbd_test_if_t    kbdmux_test_if;
static kbd_enable_t     kbdmux_enable;
static kbd_disable_t    kbdmux_disable;
static kbd_read_t       kbdmux_read;
static kbd_check_t      kbdmux_check;
static kbd_read_char_t  kbdmux_read_char;
static kbd_check_char_t kbdmux_check_char;
static kbd_ioctl_t      kbdmux_ioctl;
static kbd_lock_t       kbdmux_lock;
static kbd_clear_state_t kbdmux_clear_state;
static kbd_get_state_t  kbdmux_get_state;
static kbd_set_state_t  kbdmux_set_state;
static kbd_poll_mode_t  kbdmux_poll;

static keyboard_switch_t kbdmuxsw = {
        .probe =        kbdmux_probe,
        .init =         kbdmux_init,
        .term =         kbdmux_term,
        .intr =         kbdmux_intr,
        .test_if =      kbdmux_test_if,
        .enable =       kbdmux_enable,
        .disable =      kbdmux_disable,
        .read =         kbdmux_read,
        .check =        kbdmux_check,
        .read_char =    kbdmux_read_char,
        .check_char =   kbdmux_check_char,
        .ioctl =        kbdmux_ioctl,
        .lock =         kbdmux_lock,
        .clear_state =  kbdmux_clear_state,
        .get_state =    kbdmux_get_state,
        .set_state =    kbdmux_set_state,
        .get_fkeystr =  genkbd_get_fkeystr,
        .poll =         kbdmux_poll,
        .diag =         genkbd_diag,
};

#ifdef EVDEV_SUPPORT
static const struct evdev_methods kbdmux_evdev_methods = {
        .ev_event = evdev_ev_kbd_event,
};
#endif

/*
 * Return the number of found keyboards
 */
static int
kbdmux_configure(int flags)
{
        return (1);
}

/*
 * Detect a keyboard
 */
static int
kbdmux_probe(int unit, void *arg, int flags)
{
        if (resource_disabled(KEYBOARD_NAME, unit))
                return (ENXIO);

        return (0);
}

/*
 * Reset and initialize the keyboard (stolen from atkbd.c)
 *
 * Called without kbd lock held.
 */
static int
kbdmux_init(int unit, keyboard_t **kbdp, void *arg, int flags)
{
        kbdmux_state_t  *state = NULL;
        keymap_t        *keymap = NULL;
        accentmap_t     *accmap = NULL;
        fkeytab_t       *fkeymap = NULL;
        keyboard_t      *kbd = NULL;
        int              error, needfree, fkeymap_size, delay[2];
#ifdef EVDEV_SUPPORT
        struct evdev_dev *evdev;
        char             phys_loc[NAMELEN];
#endif

        if (*kbdp == NULL) {
                *kbdp = kbd = kmalloc(sizeof(*kbd), M_KBDMUX, M_NOWAIT | M_ZERO);
                state = kmalloc(sizeof(*state), M_KBDMUX, M_NOWAIT | M_ZERO);
                keymap = kmalloc(sizeof(key_map), M_KBDMUX, M_NOWAIT);
                accmap = kmalloc(sizeof(accent_map), M_KBDMUX, M_NOWAIT);
                fkeymap = kmalloc(sizeof(fkey_tab), M_KBDMUX, M_NOWAIT);
                fkeymap_size = NELEM(fkey_tab);
                needfree = 1;

                if ((kbd == NULL) || (state == NULL) || (keymap == NULL) ||
                    (accmap == NULL) || (fkeymap == NULL)) {
                        error = ENOMEM;
                        goto bad;
                }

                TASK_INIT(&state->ks_task, 0, kbdmux_kbd_intr, (void *) kbd);
                SLIST_INIT(&state->ks_kbds);
        } else if (KBD_IS_INITIALIZED(*kbdp) && KBD_IS_CONFIGURED(*kbdp)) {
                return (0);
        } else {
                kbd = *kbdp;
                state = (kbdmux_state_t *) kbd->kb_data;
                keymap = kbd->kb_keymap;
                accmap = kbd->kb_accentmap;
                fkeymap = kbd->kb_fkeytab;
                fkeymap_size = kbd->kb_fkeytab_size;
                needfree = 0;
        }

        if (!KBD_IS_PROBED(kbd)) {
                /* XXX assume 101/102 keys keyboard */
                kbd_init_struct(kbd, KEYBOARD_NAME, KB_101, unit, flags,
                            KB_PRI_MUX, 0, 0);
                bcopy(&key_map, keymap, sizeof(key_map));
                bcopy(&accent_map, accmap, sizeof(accent_map));
                bcopy(fkey_tab, fkeymap,
                        imin(fkeymap_size*sizeof(fkeymap[0]), sizeof(fkey_tab)));
                kbd_set_maps(kbd, keymap, accmap, fkeymap, fkeymap_size);
                kbd->kb_data = (void *)state;

                KBD_FOUND_DEVICE(kbd);
                KBD_PROBE_DONE(kbd);

                kbdmux_clear_state(kbd);
                state->ks_mode = K_XLATE;
        }

        if (!KBD_IS_INITIALIZED(kbd) && !(flags & KB_CONF_PROBE_ONLY)) {
                kbd->kb_config = flags & ~KB_CONF_PROBE_ONLY;

                kbdmux_ioctl(kbd, KDSETLED, (caddr_t)&state->ks_state);

                delay[0] = kbd->kb_delay1;
                delay[1] = kbd->kb_delay2;
                kbdmux_ioctl(kbd, KDSETREPEAT, (caddr_t)delay);

#ifdef EVDEV_SUPPORT
                /* register as evdev provider */
                evdev = evdev_alloc();
                evdev_set_name(evdev, "System keyboard multiplexer");
                ksnprintf(phys_loc, NAMELEN, KEYBOARD_NAME"%d", unit);
                evdev_set_phys(evdev, phys_loc);
                evdev_set_id(evdev, BUS_VIRTUAL, 0, 0, 0);
                evdev_set_methods(evdev, kbd, &kbdmux_evdev_methods);
                evdev_support_event(evdev, EV_SYN);
                evdev_support_event(evdev, EV_KEY);
                evdev_support_event(evdev, EV_LED);
                evdev_support_event(evdev, EV_REP);
                evdev_support_all_known_keys(evdev);
                evdev_support_led(evdev, LED_NUML);
                evdev_support_led(evdev, LED_CAPSL);
                evdev_support_led(evdev, LED_SCROLLL);

                if (evdev_register(evdev))
                        evdev_free(evdev);
                else
                        state->ks_evdev = evdev;
                state->ks_evdev_state = 0;
#endif

                KBD_INIT_DONE(kbd);
        }

        if (!KBD_IS_CONFIGURED(kbd)) {
                if (kbd_register(kbd) < 0) {
                        error = ENXIO;
                        goto bad;
                }

                KBD_CONFIG_DONE(kbd);
        }

        return (0);
bad:
        if (needfree) {
                if (state != NULL)
                        kfree(state, M_KBDMUX);
                if (keymap != NULL)
                        kfree(keymap, M_KBDMUX);
                if (accmap != NULL)
                        kfree(accmap, M_KBDMUX);
                if (fkeymap != NULL)
                        kfree(fkeymap, M_KBDMUX);
                if (kbd != NULL) {
                        kfree(kbd, M_KBDMUX);
                        *kbdp = NULL;   /* insure ref doesn't leak to caller */
                }
        }

        return (error);
}

/*
 * Finish using this keyboard
 *
 * NOTE: deregistration automatically unlocks lock.
 */
static int
kbdmux_term(keyboard_t *kbd)
{
        kbdmux_state_t  *state = (kbdmux_state_t *) kbd->kb_data;
        kbdmux_kbd_t    *k;

        /* wait for interrupt task */
        while (taskqueue_cancel(taskqueue_swi, &state->ks_task, NULL) != 0)
                taskqueue_drain(taskqueue_swi, &state->ks_task);

        /* release all keyboards from the mux */
        while ((k = SLIST_FIRST(&state->ks_kbds)) != NULL) {
                kbd_release(k->kbd, &k->kbd);
                SLIST_REMOVE_HEAD(&state->ks_kbds, next);

                k->kbd = NULL;

                kfree(k, M_KBDMUX);
        }

        kbd_unregister(kbd);

#ifdef EVDEV_SUPPORT
        evdev_free(state->ks_evdev);
#endif

        bzero(state, sizeof(*state));
        kfree(state, M_KBDMUX);

        kfree(kbd->kb_keymap, M_KBDMUX);
        kfree(kbd->kb_accentmap, M_KBDMUX);
        kfree(kbd->kb_fkeytab, M_KBDMUX);
        kfree(kbd, M_KBDMUX);

        return (0);
}

/*
 * Keyboard interrupt routine
 */
static int
kbdmux_intr(keyboard_t *kbd, void *arg)
{
        int     c;

        if (KBD_IS_ACTIVE(kbd) && KBD_IS_BUSY(kbd)) {
                /* let the callback function to process the input */
                (*kbd->kb_callback.kc_func)(kbd, KBDIO_KEYINPUT,
                                            kbd->kb_callback.kc_arg);
        } else {
                /* read and discard the input; no one is waiting for input */
                do {
                        c = kbdmux_read_char(kbd, FALSE);
                } while (c != NOKEY);
        }

        return (0);
}

/*
 * Test the interface to the device
 */
static int
kbdmux_test_if(keyboard_t *kbd)
{
        return (0);
}

/*
 * Enable the access to the device; until this function is called,
 * the client cannot read from the keyboard.
 */
static int
kbdmux_enable(keyboard_t *kbd)
{
        KBD_ACTIVATE(kbd);
        return (0);
}

/*
 * Disallow the access to the device
 */
static int
kbdmux_disable(keyboard_t *kbd)
{
        KBD_DEACTIVATE(kbd);
        return (0);
}

/*
 * Read one byte from the keyboard if it's allowed
 */
static int
kbdmux_read(keyboard_t *kbd, int wait)
{
        kbdmux_state_t  *state = (kbdmux_state_t *) kbd->kb_data;
        int              c, ret;

        do {
                c = kbdmux_kbd_getc(state);
        } while (c == -1 && wait);

        if (c != -1)
                kbd->kb_count++;

        ret = (KBD_IS_ACTIVE(kbd)? c : -1);

        return ret;
}

/*
 * Check if data is waiting
 */
static int
kbdmux_check(keyboard_t *kbd)
{
        kbdmux_state_t  *state = (kbdmux_state_t *) kbd->kb_data;
        int              ready;

        if (!KBD_IS_ACTIVE(kbd))
                return (FALSE);

        ready = (state->ks_inq_length > 0) ? TRUE : FALSE;

        return (ready);
}

/*
 * Read char from the keyboard (stolen from atkbd.c)
 *
 * Note: We do not attempt to detect the case where no keyboards are
 *       present in the wait case.  If the kernel is sitting at the
 *       debugger prompt we want someone to be able to plug in a keyboard
 *       and have it work, and not just panic or fall through or do
 *       something equally nasty.
 */
static u_int
kbdmux_read_char(keyboard_t *kbd, int wait)
{
        kbdmux_state_t  *state = (kbdmux_state_t *) kbd->kb_data;
        u_int            action;
        int              scancode, keycode;

next_code:

        /* do we have a composed char to return? */
        if (!(state->ks_flags & COMPOSE) && (state->ks_composed_char > 0)) {
                action = state->ks_composed_char;
                state->ks_composed_char = 0;
                if (action > UCHAR_MAX) {
                        return (ERRKEY);
                }
                return (action);
        }

        /*
         * See if there is something in the keyboard queue
         */
        scancode = kbdmux_kbd_getc(state);

        if (scancode == -1) {
                if (state->ks_flags & POLLING) {
                        kbdmux_kbd_t    *k;

                        SLIST_FOREACH(k, &state->ks_kbds, next) {
                                while (kbd_check_char(k->kbd)) {
                                        scancode = kbd_read_char(k->kbd, 0);
                                        if (scancode == ERRKEY)
                                                continue;
                                        if (scancode == NOKEY)
                                                break;
                                        if (!KBD_IS_BUSY(k->kbd))
                                                continue;
                                        kbdmux_kbd_putc(state, scancode);
                                }
                        }

                        if (state->ks_inq_length > 0)
                                goto next_code;
                        if (wait)
                                goto next_code;
                } else {
                        if (wait) {
                                if (kbd->kb_flags & KB_POLLED) {
                                        tsleep(&state->ks_task, PCATCH,
                                                "kbdwai", hz/10);
                                } else {
                                        lksleep(&state->ks_task,
                                                &kbd->kb_lock, PCATCH,
                                                "kbdwai", hz/10);
                                }
                                goto next_code;
                        }
                }
                return (NOKEY);
        }

        kbd->kb_count++;

#ifdef EVDEV_SUPPORT
        /* push evdev event */
        if (evdev_rcpt_mask & EVDEV_RCPT_KBDMUX && state->ks_evdev != NULL) {
                uint16_t key = evdev_scancode2key(&state->ks_evdev_state,
                    scancode);

                if (key != KEY_RESERVED) {
                        evdev_push_event(state->ks_evdev, EV_KEY,
                            key, scancode & 0x80 ? 0 : 1);
                        evdev_sync(state->ks_evdev);
                }
        }
#endif

        /* return the byte as is for the K_RAW mode */
        if (state->ks_mode == K_RAW)
                return (scancode);

        /* translate the scan code into a keycode */
        keycode = scancode & 0x7F;
        switch (state->ks_prefix) {
        case 0x00:      /* normal scancode */
                switch(scancode) {
                case 0xB8:      /* left alt (compose key) released */
                        if (state->ks_flags & COMPOSE) {
                                state->ks_flags &= ~COMPOSE;
                                if (state->ks_composed_char > UCHAR_MAX)
                                        state->ks_composed_char = 0;
                        }
                        break;
                case 0x38:      /* left alt (compose key) pressed */
                        if (!(state->ks_flags & COMPOSE)) {
                                state->ks_flags |= COMPOSE;
                                state->ks_composed_char = 0;
                        }
                        break;
                case 0xE0:
                case 0xE1:
                        state->ks_prefix = scancode;
                        goto next_code;
                }
                break;
        case 0xE0:      /* 0xE0 prefix */
                state->ks_prefix = 0;
                switch (keycode) {
                case 0x1C:      /* right enter key */
                        keycode = 0x59;
                        break;
                case 0x1D:      /* right ctrl key */
                        keycode = 0x5A;
                        break;
                case 0x35:      /* keypad divide key */
                        keycode = 0x5B;
                        break;
                case 0x37:      /* print scrn key */
                        keycode = 0x5C;
                        break;
                case 0x38:      /* right alt key (alt gr) */
                        keycode = 0x5D;
                        break;
                case 0x46:      /* ctrl-pause/break on AT 101 (see below) */
                        keycode = 0x68;
                        break;
                case 0x47:      /* grey home key */
                        keycode = 0x5E;
                        break;
                case 0x48:      /* grey up arrow key */
                        keycode = 0x5F;
                        break;
                case 0x49:      /* grey page up key */
                        keycode = 0x60;
                        break;
                case 0x4B:      /* grey left arrow key */
                        keycode = 0x61;
                        break;
                case 0x4D:      /* grey right arrow key */
                        keycode = 0x62;
                        break;
                case 0x4F:      /* grey end key */
                        keycode = 0x63;
                        break;
                case 0x50:      /* grey down arrow key */
                        keycode = 0x64;
                        break;
                case 0x51:      /* grey page down key */
                        keycode = 0x65;
                        break;
                case 0x52:      /* grey insert key */
                        keycode = 0x66;
                        break;
                case 0x53:      /* grey delete key */
                        keycode = 0x67;
                        break;
                /* the following 3 are only used on the MS "Natural" keyboard */
                case 0x5b:      /* left Window key */
                        keycode = 0x69;
                        break;
                case 0x5c:      /* right Window key */
                        keycode = 0x6a;
                        break;
                case 0x5d:      /* menu key */
                        keycode = 0x6b;
                        break;
                case 0x5e:      /* power key */
                        keycode = 0x6d;
                        break;
                case 0x5f:      /* sleep key */
                        keycode = 0x6e;
                        break;
                case 0x63:      /* wake key */
                        keycode = 0x6f;
                        break;
                case 0x64:      /* [JP106USB] backslash, underscore */
                        keycode = 0x73;
                        break;
                default:        /* ignore everything else */
                        goto next_code;
                }
                break;
        case 0xE1:      /* 0xE1 prefix */
                /*
                 * The pause/break key on the 101 keyboard produces:
                 * E1-1D-45 E1-9D-C5
                 * Ctrl-pause/break produces:
                 * E0-46 E0-C6 (See above.)
                 */
                state->ks_prefix = 0;
                if (keycode == 0x1D)
                        state->ks_prefix = 0x1D;
                goto next_code;
                /* NOT REACHED */
        case 0x1D:      /* pause / break */
                state->ks_prefix = 0;
                if (keycode != 0x45)
                        goto next_code;
                keycode = 0x68;
                break;
        }

        /* XXX assume 101/102 keys AT keyboard */
        switch (keycode) {
        case 0x5c:      /* print screen */
                if (state->ks_flags & ALTS)
                        keycode = 0x54; /* sysrq */
                break;
        case 0x68:      /* pause/break */
                if (state->ks_flags & CTLS)
                        keycode = 0x6c; /* break */
                break;
        }

        /* return the key code in the K_CODE mode */
        if (state->ks_mode == K_CODE)
                return (keycode | (scancode & 0x80));

        /* compose a character code */
        if (state->ks_flags & COMPOSE) {
                switch (keycode | (scancode & 0x80)) {
                /* key pressed, process it */
                case 0x47: case 0x48: case 0x49:        /* keypad 7,8,9 */
                        state->ks_composed_char *= 10;
                        state->ks_composed_char += keycode - 0x40;
                        if (state->ks_composed_char > UCHAR_MAX)
                                return (ERRKEY);
                        goto next_code;
                case 0x4B: case 0x4C: case 0x4D:        /* keypad 4,5,6 */
                        state->ks_composed_char *= 10;
                        state->ks_composed_char += keycode - 0x47;
                        if (state->ks_composed_char > UCHAR_MAX)
                                return (ERRKEY);
                        goto next_code;
                case 0x4F: case 0x50: case 0x51:        /* keypad 1,2,3 */
                        state->ks_composed_char *= 10;
                        state->ks_composed_char += keycode - 0x4E;
                        if (state->ks_composed_char > UCHAR_MAX)
                                return (ERRKEY);
                        goto next_code;
                case 0x52:      /* keypad 0 */
                        state->ks_composed_char *= 10;
                        if (state->ks_composed_char > UCHAR_MAX)
                                return (ERRKEY);
                        goto next_code;

                /* key released, no interest here */
                case 0xC7: case 0xC8: case 0xC9:        /* keypad 7,8,9 */
                case 0xCB: case 0xCC: case 0xCD:        /* keypad 4,5,6 */
                case 0xCF: case 0xD0: case 0xD1:        /* keypad 1,2,3 */
                case 0xD2:                              /* keypad 0 */
                        goto next_code;

                case 0x38:                              /* left alt key */
                        break;

                default:
                        if (state->ks_composed_char > 0) {
                                state->ks_flags &= ~COMPOSE;
                                state->ks_composed_char = 0;
                                return (ERRKEY);
                        }
                        break;
                }
        }

        /* keycode to key action */
        action = genkbd_keyaction(kbd, keycode, scancode & 0x80,
                        &state->ks_state, &state->ks_accents);
        if (action == NOKEY)
                goto next_code;

        return (action);
}

/*
 * Check if char is waiting
 */
static int
kbdmux_check_char(keyboard_t *kbd)
{
        kbdmux_state_t  *state = (kbdmux_state_t *) kbd->kb_data;
        int              ready;

        if (!KBD_IS_ACTIVE(kbd))
                return (FALSE);

        if (!(state->ks_flags & COMPOSE) && (state->ks_composed_char != 0))
                ready = TRUE;
        else
                ready = (state->ks_inq_length > 0) ? TRUE : FALSE;

        return (ready);
}

/*
 * Keyboard ioctl's
 */
static int
kbdmux_ioctl(keyboard_t *kbd, u_long cmd, caddr_t arg)
{
        static int       delays[] = {
                250, 500, 750, 1000
        };

        static int       rates[]  =  {
                34,  38,  42,  46,  50,   55,  59,  63,
                68,  76,  84,  92,  100, 110, 118, 126,
                136, 152, 168, 184, 200, 220, 236, 252,
                272, 304, 336, 368, 400, 440, 472, 504
        };

        kbdmux_state_t  *state = (kbdmux_state_t *) kbd->kb_data;
        kbdmux_kbd_t    *k;
        keyboard_info_t *ki;
        int              error = 0, mode, i;

        if (state == NULL)
                return (ENXIO);

        switch (cmd) {
        case KBADDKBD: /* add keyboard to the mux */
                ki = (keyboard_info_t *) arg;

                if (ki == NULL || ki->kb_unit < 0 || ki->kb_name[0] == '\0' ||
                    strcmp(ki->kb_name, "*") == 0) {
                        return (EINVAL); /* bad input */
                }

                SLIST_FOREACH(k, &state->ks_kbds, next)
                        if (k->kbd->kb_unit == ki->kb_unit &&
                            strcmp(k->kbd->kb_name, ki->kb_name) == 0)
                                break;

                if (k != NULL)
                        return (0); /* keyboard already in the mux */

                k = kmalloc(sizeof(*k), M_KBDMUX, M_NOWAIT | M_ZERO);
                if (k == NULL)
                        return (ENOMEM); /* out of memory */

                k->kbd = kbd_get_keyboard(
                                kbd_allocate(
                                        ki->kb_name,
                                        ki->kb_unit,
                                        (void *) &k->kbd,
                                        kbdmux_kbd_event, (void *) state));
                if (k->kbd == NULL) {
                        kfree(k, M_KBDMUX);
                        return (EINVAL); /* bad keyboard */
                }

                kbd_enable(k->kbd);
                kbd_clear_state(k->kbd);

                /* set K_RAW mode on slave keyboard */
                mode = K_RAW;
                error = kbd_ioctl(k->kbd, KDSKBMODE, (caddr_t)&mode);
                if (error == 0) {
                        /* set lock keys state on slave keyboard */
                        mode = state->ks_state & LOCK_MASK;
                        error = kbd_ioctl(k->kbd, KDSKBSTATE, (caddr_t)&mode);
                }

                if (error != 0) {
                        kbd_release(k->kbd, &k->kbd);
                        k->kbd = NULL;
                        kfree(k, M_KBDMUX);
                        return (error); /* could not set mode */
                }

                SLIST_INSERT_HEAD(&state->ks_kbds, k, next);
                break;

        case KBRELKBD: /* release keyboard from the mux */
                ki = (keyboard_info_t *) arg;

                if (ki == NULL || ki->kb_unit < 0 || ki->kb_name[0] == '\0' ||
                    strcmp(ki->kb_name, "*") == 0) {
                        return (EINVAL); /* bad input */
                }

                SLIST_FOREACH(k, &state->ks_kbds, next)
                        if (k->kbd->kb_unit == ki->kb_unit &&
                            strcmp(k->kbd->kb_name, ki->kb_name) == 0)
                                break;

                if (k != NULL) {
                        error = kbd_release(k->kbd, &k->kbd);
                        if (error == 0) {
                                SLIST_REMOVE(&state->ks_kbds, k, kbdmux_kbd, next);

                                k->kbd = NULL;

                                kfree(k, M_KBDMUX);
                        }
                } else
                        error = ENXIO; /* keyboard is not in the mux */

                break;

        case KDGKBMODE: /* get kyboard mode */
                *(int *)arg = state->ks_mode;
                break;

        case KDSKBMODE: /* set keyboard mode */
                switch (*(int *)arg) {
                case K_XLATE:
                        if (state->ks_mode != K_XLATE) {
                                /* make lock key state and LED state match */
                                state->ks_state &= ~LOCK_MASK;
                                state->ks_state |= KBD_LED_VAL(kbd);
                        }
                        /* FALLTHROUGH */

                case K_RAW:
                case K_CODE:
                        if (state->ks_mode != *(int *)arg) {
                                kbdmux_clear_state(kbd);
                                state->ks_mode = *(int *)arg;
                        }
                        break;

                default:
                        error = EINVAL;
                        break;
                }
                break;

        case KDGETLED: /* get keyboard LED */
                *(int *)arg = KBD_LED_VAL(kbd);
                break;

        case KDSETLED: /* set keyboard LED */
                /* NOTE: lock key state in ks_state won't be changed */
                if (*(int *)arg & ~LOCK_MASK)
                        return (EINVAL);

                KBD_LED_VAL(kbd) = *(int *)arg;
#ifdef EVDEV_SUPPORT
                if (state->ks_evdev != NULL &&
                    evdev_rcpt_mask & EVDEV_RCPT_KBDMUX)
                        evdev_push_leds(state->ks_evdev, *(int *)arg);
#endif
                /* KDSETLED on all slave keyboards */
                SLIST_FOREACH(k, &state->ks_kbds, next)
                        kbd_ioctl(k->kbd, KDSETLED, arg);
                break;

        case KDGKBSTATE: /* get lock key state */
                *(int *)arg = state->ks_state & LOCK_MASK;
                break;

        case KDSKBSTATE: /* set lock key state */
                if (*(int *)arg & ~LOCK_MASK)
                        return (EINVAL);

                state->ks_state &= ~LOCK_MASK;
                state->ks_state |= *(int *)arg;

                /* KDSKBSTATE on all slave keyboards */
                SLIST_FOREACH(k, &state->ks_kbds, next)
                        kbd_ioctl(k->kbd, KDSKBSTATE, arg);

                return (kbdmux_ioctl(kbd, KDSETLED, arg));
                /* NOT REACHED */

        case KDSETREPEAT: /* set keyboard repeat rate (new interface) */
                /* lookup delay */
                for (i = NELEM(delays) - 1; i > 0; i --)
                        if (((int *)arg)[0] >= delays[i])
                                break;
                mode = i << 5;

                /* lookup rate */
                for (i = NELEM(rates) - 1; i > 0; i --)
                        if (((int *)arg)[1] >= rates[i])
                                break;
                mode |= i;

                if (mode & ~0x7f)
                        return (EINVAL);

                kbd->kb_delay1 = delays[(mode >> 5) & 3];
                kbd->kb_delay2 = rates[mode & 0x1f];
#ifdef EVDEV_SUPPORT
                if (state->ks_evdev != NULL &&
                    evdev_rcpt_mask & EVDEV_RCPT_KBDMUX)
                        evdev_push_repeats(state->ks_evdev, kbd);
#endif
                /* perform command on all slave keyboards */
                SLIST_FOREACH(k, &state->ks_kbds, next)
                        kbd_ioctl(k->kbd, cmd, arg);
                break;

        case PIO_KEYMAP:        /* set keyboard translation table */
        case PIO_KEYMAPENT:     /* set keyboard translation table entry */
        case PIO_DEADKEYMAP:    /* set accent key translation table */
                state->ks_accents = 0;

                /* perform command on all slave keyboards */
                SLIST_FOREACH(k, &state->ks_kbds, next)
                        kbd_ioctl(k->kbd, cmd, arg);
                /* FALLTHROUGH */

        default:
                error = genkbd_commonioctl(kbd, cmd, arg);
                break;
        }
        return (error);
}

/*
 * Lock the access to the keyboard
 */
static int
kbdmux_lock(keyboard_t *kbd, int lock)
{
        return (1); /* XXX */
}

/*
 * Clear the internal state of the keyboard
 *
 * NOTE: May be called unlocked from init
 */
static void
kbdmux_clear_state(keyboard_t *kbd)
{
        kbdmux_state_t *state = (kbdmux_state_t *) kbd->kb_data;

        state->ks_flags &= ~(COMPOSE|POLLING);
        state->ks_state &= LOCK_MASK;   /* preserve locking key state */
        state->ks_accents = 0;
        state->ks_composed_char = 0;
/*      state->ks_prefix = 0;           XXX */
        state->ks_inq_length = 0;
}

/*
 * Save the internal state
 */
static int
kbdmux_get_state(keyboard_t *kbd, void *buf, size_t len)
{
        if (len == 0)
                return (sizeof(kbdmux_state_t));
        if (len < sizeof(kbdmux_state_t))
                return (-1);

        bcopy(kbd->kb_data, buf, sizeof(kbdmux_state_t)); /* XXX locking? */

        return (0);
}

/*
 * Set the internal state
 */
static int
kbdmux_set_state(keyboard_t *kbd, void *buf, size_t len)
{
        if (len < sizeof(kbdmux_state_t))
                return (ENOMEM);

        bcopy(buf, kbd->kb_data, sizeof(kbdmux_state_t)); /* XXX locking? */

        return (0);
}

/*
 * Set polling
 *
 * Caller interlocks all keyboard calls.  We must not lock here.
 */
static int
kbdmux_poll(keyboard_t *kbd, int on)
{
        kbdmux_state_t  *state = (kbdmux_state_t *) kbd->kb_data;
        kbdmux_kbd_t    *k;

        if (on)
                state->ks_flags |= POLLING;
        else
                state->ks_flags &= ~POLLING;

        /* set poll on slave keyboards */
        SLIST_FOREACH(k, &state->ks_kbds, next)
                kbd_poll(k->kbd, on);

        return (0);
}

/*****************************************************************************
 *****************************************************************************
 **                                    Module
 *****************************************************************************
 *****************************************************************************/

KEYBOARD_DRIVER(kbdmux, kbdmuxsw, kbdmux_configure);

static int
kbdmux_modevent(module_t mod, int type, void *data)
{
        keyboard_switch_t       *sw;
        keyboard_t              *kbd;
        int                      error;

        switch (type) {
        case MOD_LOAD:
                if ((error = kbd_add_driver(&kbdmux_kbd_driver)) != 0)
                        break;

                if ((sw = kbd_get_switch(KEYBOARD_NAME)) == NULL) {
                        kbd_delete_driver(&kbdmux_kbd_driver);
                        error = ENXIO;
                        break;
                }

                kbd = NULL;

                if ((error = (*sw->probe)(0, NULL, 0)) != 0 ||
                    (error = (*sw->init)(0, &kbd, NULL, 0)) != 0) {
                        kbd_delete_driver(&kbdmux_kbd_driver);
                        break;
                }

#ifdef KBD_INSTALL_CDEV
                if ((error = kbd_attach(kbd)) != 0) {
                        (*sw->term)(kbd);
                        kbd_delete_driver(&kbdmux_kbd_driver);
                        break;
                }
#endif

                if ((error = (*sw->enable)(kbd)) != 0) {
                        (*sw->disable)(kbd);
#ifdef KBD_INSTALL_CDEV
                        kbd_detach(kbd);
#endif
                        (*sw->term)(kbd);
                        kbd_delete_driver(&kbdmux_kbd_driver);
                        break;
                }
                break;

        case MOD_UNLOAD:
                if ((sw = kbd_get_switch(KEYBOARD_NAME)) == NULL)
                        panic("kbd_get_switch(" KEYBOARD_NAME ") == NULL");

                kbd = kbd_get_keyboard(kbd_find_keyboard(KEYBOARD_NAME, 0));
                if (kbd != NULL) {
                        (*sw->disable)(kbd);
#ifdef KBD_INSTALL_CDEV
                        kbd_detach(kbd);
#endif
                        (*sw->term)(kbd);
                        kbd_delete_driver(&kbdmux_kbd_driver);
                }
                error = 0;
                break;

        default:
                error = EOPNOTSUPP;
                break;
        }
        return (error);
}

DEV_MODULE(kbdmux, kbdmux_modevent, NULL);
#ifdef EVDEV_SUPPORT
MODULE_DEPEND(kbdmux, evdev, 1, 1, 1);
#endif