Import 2.3.13pre7

[davej-history.git] / drivers / char / keyboard.c

/*
 * linux/drivers/char/keyboard.c
 *
 * Written for linux by Johan Myreen as a translation from
 * the assembly version by Linus (with diacriticals added)
 *
 * Some additional features added by Christoph Niemann (ChN), March 1993
 *
 * Loadable keymaps by Risto Kankkunen, May 1993
 *
 * Diacriticals redone & other small changes, aeb@cwi.nl, June 1993
 * Added decr/incr_console, dynamic keymaps, Unicode support,
 * dynamic function/string keys, led setting,  Sept 1994
 * `Sticky' modifier keys, 951006.
 *
 * 11-11-96: SAK should now work in the raw mode (Martin Mares)
 * 
 * Modified to provide 'generic' keyboard support by Hamish Macdonald
 * Merge with the m68k keyboard driver and split-off of the PC low-level
 * parts by Geert Uytterhoeven, May 1997
 *
 * 27-05-97: Added support for the Magic SysRq Key (Martin Mares)
 * 30-07-98: Dead keys redone, aeb@cwi.nl.
 */

#include <linux/config.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/random.h>
#include <linux/init.h>

#include <asm/keyboard.h>
#include <asm/bitops.h>

#include <linux/kbd_kern.h>
#include <linux/kbd_diacr.h>
#include <linux/vt_kern.h>
#include <linux/kbd_ll.h>
#include <linux/sysrq.h>

#define SIZE(x) (sizeof(x)/sizeof((x)[0]))

#ifndef KBD_DEFMODE
#define KBD_DEFMODE ((1 << VC_REPEAT) | (1 << VC_META))
#endif

#ifndef KBD_DEFLEDS
/*
 * Some laptops take the 789uiojklm,. keys as number pad when NumLock
 * is on. This seems a good reason to start with NumLock off.
 */
#define KBD_DEFLEDS 0
#endif

#ifndef KBD_DEFLOCK
#define KBD_DEFLOCK 0
#endif

EXPORT_SYMBOL(handle_scancode);

extern void ctrl_alt_del(void);

DECLARE_WAIT_QUEUE_HEAD(keypress_wait);
struct console;

int keyboard_wait_for_keypress(struct console *co)
{
        sleep_on(&keypress_wait);
        return 0;
}

/*
 * global state includes the following, and various static variables
 * in this module: prev_scancode, shift_state, diacr, npadch, dead_key_next.
 * (last_console is now a global variable)
 */

/* shift state counters.. */
static unsigned char k_down[NR_SHIFT] = {0, };
/* keyboard key bitmap */
static unsigned long key_down[256/BITS_PER_LONG] = { 0, };

static int dead_key_next = 0;
/* 
 * In order to retrieve the shift_state (for the mouse server), either
 * the variable must be global, or a new procedure must be created to 
 * return the value. I chose the former way.
 */
int shift_state = 0;
static int npadch = -1;                 /* -1 or number assembled on pad */
static unsigned char diacr = 0;
static char rep = 0;                    /* flag telling character repeat */
struct kbd_struct kbd_table[MAX_NR_CONSOLES];
static struct tty_struct **ttytab;
static struct kbd_struct * kbd = kbd_table;
static struct tty_struct * tty = NULL;

void compute_shiftstate(void);

typedef void (*k_hand)(unsigned char value, char up_flag);
typedef void (k_handfn)(unsigned char value, char up_flag);

static k_handfn
        do_self, do_fn, do_spec, do_pad, do_dead, do_cons, do_cur, do_shift,
        do_meta, do_ascii, do_lock, do_lowercase, do_slock, do_dead2,
        do_ignore;

static k_hand key_handler[16] = {
        do_self, do_fn, do_spec, do_pad, do_dead, do_cons, do_cur, do_shift,
        do_meta, do_ascii, do_lock, do_lowercase, do_slock, do_dead2,
        do_ignore, do_ignore
};

/* Key types processed even in raw modes */

#define TYPES_ALLOWED_IN_RAW_MODE ((1 << KT_SPEC) | (1 << KT_SHIFT))

typedef void (*void_fnp)(void);
typedef void (void_fn)(void);

static void_fn do_null, enter, show_ptregs, send_intr, lastcons, caps_toggle,
        num, hold, scroll_forw, scroll_back, boot_it, caps_on, compose,
        SAK, decr_console, incr_console, spawn_console, bare_num;

static void_fnp spec_fn_table[] = {
        do_null,        enter,          show_ptregs,    show_mem,
        show_state,     send_intr,      lastcons,       caps_toggle,
        num,            hold,           scroll_forw,    scroll_back,
        boot_it,        caps_on,        compose,        SAK,
        decr_console,   incr_console,   spawn_console,  bare_num
};

#define SPECIALS_ALLOWED_IN_RAW_MODE (1 << KVAL(K_SAK))

/* maximum values each key_handler can handle */
const int max_vals[] = {
        255, SIZE(func_table) - 1, SIZE(spec_fn_table) - 1, NR_PAD - 1,
        NR_DEAD - 1, 255, 3, NR_SHIFT - 1,
        255, NR_ASCII - 1, NR_LOCK - 1, 255,
        NR_LOCK - 1, 255
};

const int NR_TYPES = SIZE(max_vals);

/* N.B. drivers/macintosh/mac_keyb.c needs to call put_queue */
void put_queue(int);
static unsigned char handle_diacr(unsigned char);

/* kbd_pt_regs - set by keyboard_interrupt(), used by show_ptregs() */
struct pt_regs * kbd_pt_regs;

#ifdef CONFIG_MAGIC_SYSRQ
static int sysrq_pressed;
int sysrq_enabled = 1;
#endif

/*
 * Many other routines do put_queue, but I think either
 * they produce ASCII, or they produce some user-assigned
 * string, and in both cases we might assume that it is
 * in utf-8 already.
 */
void to_utf8(ushort c) {
    if (c < 0x80)
        put_queue(c);                   /*  0*******  */
    else if (c < 0x800) {
        put_queue(0xc0 | (c >> 6));     /*  110***** 10******  */
        put_queue(0x80 | (c & 0x3f));
    } else {
        put_queue(0xe0 | (c >> 12));    /*  1110**** 10****** 10******  */
        put_queue(0x80 | ((c >> 6) & 0x3f));
        put_queue(0x80 | (c & 0x3f));
    }
    /* UTF-8 is defined for words of up to 31 bits,
       but we need only 16 bits here */
}

/*
 * Translation of escaped scancodes to keycodes.
 * This is now user-settable (for machines were it makes sense).
 */

int setkeycode(unsigned int scancode, unsigned int keycode)
{
    return kbd_setkeycode(scancode, keycode);
}

int getkeycode(unsigned int scancode)
{
    return kbd_getkeycode(scancode);
}

void handle_scancode(unsigned char scancode, int down)
{
        unsigned char keycode;
        char up_flag = down ? 0 : 0200;
        char raw_mode;

        do_poke_blanked_console = 1;
        mark_bh(CONSOLE_BH);
        add_keyboard_randomness(scancode | up_flag);

        tty = ttytab? ttytab[fg_console]: NULL;
        if (tty && (!tty->driver_data)) {
                /*
                 * We touch the tty structure via the the ttytab array
                 * without knowing whether or not tty is open, which
                 * is inherently dangerous.  We currently rely on that
                 * fact that console_open sets tty->driver_data when
                 * it opens it, and clears it when it closes it.
                 */
                tty = NULL;
        }
        kbd = kbd_table + fg_console;
        if ((raw_mode = (kbd->kbdmode == VC_RAW))) {
                put_queue(scancode | up_flag);
                /* we do not return yet, because we want to maintain
                   the key_down array, so that we have the correct
                   values when finishing RAW mode or when changing VT's */
        }

        /*
         *  Convert scancode to keycode
         */
        if (!kbd_translate(scancode, &keycode, raw_mode))
            return;

        /*
         * At this point the variable `keycode' contains the keycode.
         * Note: the keycode must not be 0 (++Geert: on m68k 0 is valid).
         * We keep track of the up/down status of the key, and
         * return the keycode if in MEDIUMRAW mode.
         */

        if (up_flag) {
                rep = 0;
                if(!test_and_clear_bit(keycode, key_down))
                    up_flag = kbd_unexpected_up(keycode);
        } else
                rep = test_and_set_bit(keycode, key_down);

#ifdef CONFIG_MAGIC_SYSRQ               /* Handle the SysRq Hack */
        if (keycode == SYSRQ_KEY) {
                sysrq_pressed = !up_flag;
                return;
        } else if (sysrq_pressed) {
                if (!up_flag && sysrq_enabled) {
                        handle_sysrq(kbd_sysrq_xlate[keycode], kbd_pt_regs, kbd, tty);
                        return;
                }
        }
#endif

        if (kbd->kbdmode == VC_MEDIUMRAW) {
                /* soon keycodes will require more than one byte */
                put_queue(keycode + up_flag);
                raw_mode = 1;   /* Most key classes will be ignored */
        }

        /*
         * Small change in philosophy: earlier we defined repetition by
         *       rep = keycode == prev_keycode;
         *       prev_keycode = keycode;
         * but now by the fact that the depressed key was down already.
         * Does this ever make a difference? Yes.
         */

        /*
         *  Repeat a key only if the input buffers are empty or the
         *  characters get echoed locally. This makes key repeat usable
         *  with slow applications and under heavy loads.
         */
        if (!rep ||
            (vc_kbd_mode(kbd,VC_REPEAT) && tty &&
             (L_ECHO(tty) || (tty->driver.chars_in_buffer(tty) == 0)))) {
                u_short keysym;
                u_char type;

                /* the XOR below used to be an OR */
                int shift_final = (shift_state | kbd->slockstate) ^
                    kbd->lockstate;
                ushort *key_map = key_maps[shift_final];

                if (key_map != NULL) {
                        keysym = key_map[keycode];
                        type = KTYP(keysym);

                        if (type >= 0xf0) {
                            type -= 0xf0;
                            if (raw_mode && ! (TYPES_ALLOWED_IN_RAW_MODE & (1 << type)))
                                return;
                            if (type == KT_LETTER) {
                                type = KT_LATIN;
                                if (vc_kbd_led(kbd, VC_CAPSLOCK)) {
                                    key_map = key_maps[shift_final ^ (1<<KG_SHIFT)];
                                    if (key_map)
                                      keysym = key_map[keycode];
                                }
                            }
                            (*key_handler[type])(keysym & 0xff, up_flag);
                            if (type != KT_SLOCK)
                              kbd->slockstate = 0;
                        } else {
                            /* maybe only if (kbd->kbdmode == VC_UNICODE) ? */
                            if (!up_flag && !raw_mode)
                              to_utf8(keysym);
                        }
                } else {
                        /* maybe beep? */
                        /* we have at least to update shift_state */
#if 1                   /* how? two almost equivalent choices follow */
                        compute_shiftstate();
                        kbd->slockstate = 0; /* play it safe */
#else
                        keysym = U(plain_map[keycode]);
                        type = KTYP(keysym);
                        if (type == KT_SHIFT)
                          (*key_handler[type])(keysym & 0xff, up_flag);
#endif
                }
        }
}


void put_queue(int ch)
{
        wake_up(&keypress_wait);
        if (tty) {
                tty_insert_flip_char(tty, ch, 0);
                con_schedule_flip(tty);
        }
}

static void puts_queue(char *cp)
{
        wake_up(&keypress_wait);
        if (!tty)
                return;

        while (*cp) {
                tty_insert_flip_char(tty, *cp, 0);
                cp++;
        }
        con_schedule_flip(tty);
}

static void applkey(int key, char mode)
{
        static char buf[] = { 0x1b, 'O', 0x00, 0x00 };

        buf[1] = (mode ? 'O' : '[');
        buf[2] = key;
        puts_queue(buf);
}

static void enter(void)
{
        if (diacr) {
                put_queue(diacr);
                diacr = 0;
        }
        put_queue(13);
        if (vc_kbd_mode(kbd,VC_CRLF))
                put_queue(10);
}

static void caps_toggle(void)
{
        if (rep)
                return;
        chg_vc_kbd_led(kbd, VC_CAPSLOCK);
}

static void caps_on(void)
{
        if (rep)
                return;
        set_vc_kbd_led(kbd, VC_CAPSLOCK);
}

static void show_ptregs(void)
{
        if (kbd_pt_regs)
                show_regs(kbd_pt_regs);
}

static void hold(void)
{
        if (rep || !tty)
                return;

        /*
         * Note: SCROLLOCK will be set (cleared) by stop_tty (start_tty);
         * these routines are also activated by ^S/^Q.
         * (And SCROLLOCK can also be set by the ioctl KDSKBLED.)
         */
        if (tty->stopped)
                start_tty(tty);
        else
                stop_tty(tty);
}

static void num(void)
{
        if (vc_kbd_mode(kbd,VC_APPLIC))
                applkey('P', 1);
        else
                bare_num();
}

/*
 * Bind this to Shift-NumLock if you work in application keypad mode
 * but want to be able to change the NumLock flag.
 * Bind this to NumLock if you prefer that the NumLock key always
 * changes the NumLock flag.
 */
static void bare_num(void)
{
        if (!rep)
                chg_vc_kbd_led(kbd,VC_NUMLOCK);
}

static void lastcons(void)
{
        /* switch to the last used console, ChN */
        set_console(last_console);
}

static void decr_console(void)
{
        int i;
 
        for (i = fg_console-1; i != fg_console; i--) {
                if (i == -1)
                        i = MAX_NR_CONSOLES-1;
                if (vc_cons_allocated(i))
                        break;
        }
        set_console(i);
}

static void incr_console(void)
{
        int i;

        for (i = fg_console+1; i != fg_console; i++) {
                if (i == MAX_NR_CONSOLES)
                        i = 0;
                if (vc_cons_allocated(i))
                        break;
        }
        set_console(i);
}

static void send_intr(void)
{
        if (!tty)
                return;
        tty_insert_flip_char(tty, 0, TTY_BREAK);
        con_schedule_flip(tty);
}

static void scroll_forw(void)
{
        scrollfront(0);
}

static void scroll_back(void)
{
        scrollback(0);
}

static void boot_it(void)
{
        ctrl_alt_del();
}

static void compose(void)
{
        dead_key_next = 1;
}

int spawnpid, spawnsig;

static void spawn_console(void)
{
        if (spawnpid)
           if(kill_proc(spawnpid, spawnsig, 1))
             spawnpid = 0;
}

static void SAK(void)
{
        /*
         * SAK should also work in all raw modes and reset
         * them properly.
         */

        do_SAK(tty);
        reset_vc(fg_console);
#if 0
        do_unblank_screen();    /* not in interrupt routine? */
#endif
}

static void do_ignore(unsigned char value, char up_flag)
{
}

static void do_null()
{
        compute_shiftstate();
}

static void do_spec(unsigned char value, char up_flag)
{
        if (up_flag)
                return;
        if (value >= SIZE(spec_fn_table))
                return;
        if ((kbd->kbdmode == VC_RAW || kbd->kbdmode == VC_MEDIUMRAW) &&
            !(SPECIALS_ALLOWED_IN_RAW_MODE & (1 << value)))
                return;
        spec_fn_table[value]();
}

static void do_lowercase(unsigned char value, char up_flag)
{
        printk(KERN_ERR "keyboard.c: do_lowercase was called - impossible\n");
}

static void do_self(unsigned char value, char up_flag)
{
        if (up_flag)
                return;         /* no action, if this is a key release */

        if (diacr)
                value = handle_diacr(value);

        if (dead_key_next) {
                dead_key_next = 0;
                diacr = value;
                return;
        }

        put_queue(value);
}

#define A_GRAVE  '`'
#define A_ACUTE  '\''
#define A_CFLEX  '^'
#define A_TILDE  '~'
#define A_DIAER  '"'
#define A_CEDIL  ','
static unsigned char ret_diacr[NR_DEAD] =
        {A_GRAVE, A_ACUTE, A_CFLEX, A_TILDE, A_DIAER, A_CEDIL };

/* Obsolete - for backwards compatibility only */
static void do_dead(unsigned char value, char up_flag)
{
        value = ret_diacr[value];
        do_dead2(value,up_flag);
}

/*
 * Handle dead key. Note that we now may have several
 * dead keys modifying the same character. Very useful
 * for Vietnamese.
 */
static void do_dead2(unsigned char value, char up_flag)
{
        if (up_flag)
                return;

        diacr = (diacr ? handle_diacr(value) : value);
}


/*
 * We have a combining character DIACR here, followed by the character CH.
 * If the combination occurs in the table, return the corresponding value.
 * Otherwise, if CH is a space or equals DIACR, return DIACR.
 * Otherwise, conclude that DIACR was not combining after all,
 * queue it and return CH.
 */
unsigned char handle_diacr(unsigned char ch)
{
        int d = diacr;
        int i;

        diacr = 0;

        for (i = 0; i < accent_table_size; i++) {
                if (accent_table[i].diacr == d && accent_table[i].base == ch)
                        return accent_table[i].result;
        }

        if (ch == ' ' || ch == d)
                return d;

        put_queue(d);
        return ch;
}

static void do_cons(unsigned char value, char up_flag)
{
        if (up_flag)
                return;
        set_console(value);
}

static void do_fn(unsigned char value, char up_flag)
{
        if (up_flag)
                return;
        if (value < SIZE(func_table)) {
                if (func_table[value])
                        puts_queue(func_table[value]);
        } else
                printk(KERN_ERR "do_fn called with value=%d\n", value);
}

static void do_pad(unsigned char value, char up_flag)
{
        static const char *pad_chars = "0123456789+-*/\015,.?()";
        static const char *app_map = "pqrstuvwxylSRQMnnmPQ";

        if (up_flag)
                return;         /* no action, if this is a key release */

        /* kludge... shift forces cursor/number keys */
        if (vc_kbd_mode(kbd,VC_APPLIC) && !k_down[KG_SHIFT]) {
                applkey(app_map[value], 1);
                return;
        }

        if (!vc_kbd_led(kbd,VC_NUMLOCK))
                switch (value) {
                        case KVAL(K_PCOMMA):
                        case KVAL(K_PDOT):
                                do_fn(KVAL(K_REMOVE), 0);
                                return;
                        case KVAL(K_P0):
                                do_fn(KVAL(K_INSERT), 0);
                                return;
                        case KVAL(K_P1):
                                do_fn(KVAL(K_SELECT), 0);
                                return;
                        case KVAL(K_P2):
                                do_cur(KVAL(K_DOWN), 0);
                                return;
                        case KVAL(K_P3):
                                do_fn(KVAL(K_PGDN), 0);
                                return;
                        case KVAL(K_P4):
                                do_cur(KVAL(K_LEFT), 0);
                                return;
                        case KVAL(K_P6):
                                do_cur(KVAL(K_RIGHT), 0);
                                return;
                        case KVAL(K_P7):
                                do_fn(KVAL(K_FIND), 0);
                                return;
                        case KVAL(K_P8):
                                do_cur(KVAL(K_UP), 0);
                                return;
                        case KVAL(K_P9):
                                do_fn(KVAL(K_PGUP), 0);
                                return;
                        case KVAL(K_P5):
                                applkey('G', vc_kbd_mode(kbd, VC_APPLIC));
                                return;
                }

        put_queue(pad_chars[value]);
        if (value == KVAL(K_PENTER) && vc_kbd_mode(kbd, VC_CRLF))
                put_queue(10);
}

static void do_cur(unsigned char value, char up_flag)
{
        static const char *cur_chars = "BDCA";
        if (up_flag)
                return;

        applkey(cur_chars[value], vc_kbd_mode(kbd,VC_CKMODE));
}

static void do_shift(unsigned char value, char up_flag)
{
        int old_state = shift_state;

        if (rep)
                return;

        /* Mimic typewriter:
           a CapsShift key acts like Shift but undoes CapsLock */
        if (value == KVAL(K_CAPSSHIFT)) {
                value = KVAL(K_SHIFT);
                if (!up_flag)
                        clr_vc_kbd_led(kbd, VC_CAPSLOCK);
        }

        if (up_flag) {
                /* handle the case that two shift or control
                   keys are depressed simultaneously */
                if (k_down[value])
                        k_down[value]--;
        } else
                k_down[value]++;

        if (k_down[value])
                shift_state |= (1 << value);
        else
                shift_state &= ~ (1 << value);

        /* kludge */
        if (up_flag && shift_state != old_state && npadch != -1) {
                if (kbd->kbdmode == VC_UNICODE)
                  to_utf8(npadch & 0xffff);
                else
                  put_queue(npadch & 0xff);
                npadch = -1;
        }
}

/* called after returning from RAW mode or when changing consoles -
   recompute k_down[] and shift_state from key_down[] */
/* maybe called when keymap is undefined, so that shiftkey release is seen */
void compute_shiftstate(void)
{
        int i, j, k, sym, val;

        shift_state = 0;
        for(i=0; i < SIZE(k_down); i++)
          k_down[i] = 0;

        for(i=0; i < SIZE(key_down); i++)
          if(key_down[i]) {     /* skip this word if not a single bit on */
            k = i*BITS_PER_LONG;
            for(j=0; j<BITS_PER_LONG; j++,k++)
              if(test_bit(k, key_down)) {
                sym = U(plain_map[k]);
                if(KTYP(sym) == KT_SHIFT || KTYP(sym) == KT_SLOCK) {
                  val = KVAL(sym);
                  if (val == KVAL(K_CAPSSHIFT))
                    val = KVAL(K_SHIFT);
                  k_down[val]++;
                  shift_state |= (1<<val);
                }
              }
          }
}

static void do_meta(unsigned char value, char up_flag)
{
        if (up_flag)
                return;

        if (vc_kbd_mode(kbd, VC_META)) {
                put_queue('\033');
                put_queue(value);
        } else
                put_queue(value | 0x80);
}

static void do_ascii(unsigned char value, char up_flag)
{
        int base;

        if (up_flag)
                return;

        if (value < 10)    /* decimal input of code, while Alt depressed */
            base = 10;
        else {       /* hexadecimal input of code, while AltGr depressed */
            value -= 10;
            base = 16;
        }

        if (npadch == -1)
          npadch = value;
        else
          npadch = npadch * base + value;
}

static void do_lock(unsigned char value, char up_flag)
{
        if (up_flag || rep)
                return;
        chg_vc_kbd_lock(kbd, value);
}

static void do_slock(unsigned char value, char up_flag)
{
        do_shift(value,up_flag);
        if (up_flag || rep)
                return;
        chg_vc_kbd_slock(kbd, value);
        /* try to make Alt, oops, AltGr and such work */
        if (!key_maps[kbd->lockstate ^ kbd->slockstate]) {
                kbd->slockstate = 0;
                chg_vc_kbd_slock(kbd, value);
        }
}

/*
 * The leds display either (i) the status of NumLock, CapsLock, ScrollLock,
 * or (ii) whatever pattern of lights people want to show using KDSETLED,
 * or (iii) specified bits of specified words in kernel memory.
 */

static unsigned char ledstate = 0xff; /* undefined */
static unsigned char ledioctl;

unsigned char getledstate(void) {
    return ledstate;
}

void setledstate(struct kbd_struct *kbd, unsigned int led) {
    if (!(led & ~7)) {
        ledioctl = led;
        kbd->ledmode = LED_SHOW_IOCTL;
    } else
        kbd->ledmode = LED_SHOW_FLAGS;
    set_leds();
}

static struct ledptr {
    unsigned int *addr;
    unsigned int mask;
    unsigned char valid:1;
} ledptrs[3];

void register_leds(int console, unsigned int led,
                   unsigned int *addr, unsigned int mask) {
    struct kbd_struct *kbd = kbd_table + console;
    if (led < 3) {
        ledptrs[led].addr = addr;
        ledptrs[led].mask = mask;
        ledptrs[led].valid = 1;
        kbd->ledmode = LED_SHOW_MEM;
    } else
        kbd->ledmode = LED_SHOW_FLAGS;
}

static inline unsigned char getleds(void){
    struct kbd_struct *kbd = kbd_table + fg_console;
    unsigned char leds;

    if (kbd->ledmode == LED_SHOW_IOCTL)
      return ledioctl;
    leds = kbd->ledflagstate;
    if (kbd->ledmode == LED_SHOW_MEM) {
        if (ledptrs[0].valid) {
            if (*ledptrs[0].addr & ledptrs[0].mask)
              leds |= 1;
            else
              leds &= ~1;
        }
        if (ledptrs[1].valid) {
            if (*ledptrs[1].addr & ledptrs[1].mask)
              leds |= 2;
            else
              leds &= ~2;
        }
        if (ledptrs[2].valid) {
            if (*ledptrs[2].addr & ledptrs[2].mask)
              leds |= 4;
            else
              leds &= ~4;
        }
    }
    return leds;
}

/*
 * This routine is the bottom half of the keyboard interrupt
 * routine, and runs with all interrupts enabled. It does
 * console changing, led setting and copy_to_cooked, which can
 * take a reasonably long time.
 *
 * Aside from timing (which isn't really that important for
 * keyboard interrupts as they happen often), using the software
 * interrupt routines for this thing allows us to easily mask
 * this when we don't want any of the above to happen. Not yet
 * used, but this allows for easy and efficient race-condition
 * prevention later on.
 */
static void kbd_bh(void)
{
        unsigned char leds = getleds();

        if (leds != ledstate) {
                ledstate = leds;
                kbd_leds(leds);
        }
}

__initfunc(int kbd_init(void))
{
        int i;
        struct kbd_struct kbd0;
        extern struct tty_driver console_driver;

        kbd0.ledflagstate = kbd0.default_ledflagstate = KBD_DEFLEDS;
        kbd0.ledmode = LED_SHOW_FLAGS;
        kbd0.lockstate = KBD_DEFLOCK;
        kbd0.slockstate = 0;
        kbd0.modeflags = KBD_DEFMODE;
        kbd0.kbdmode = VC_XLATE;
 
        for (i = 0 ; i < MAX_NR_CONSOLES ; i++)
                kbd_table[i] = kbd0;

        ttytab = console_driver.table;

        kbd_init_hw();
        init_bh(KEYBOARD_BH, kbd_bh);
        mark_bh(KEYBOARD_BH);
        return 0;
}