pckbd.c

/*
 * QEMU PC keyboard emulation
 * 
 * Copyright (c) 2003 Fabrice Bellard
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>
#include <string.h>
#include <getopt.h>
#include <inttypes.h>
#include <unistd.h>
#include <sys/mman.h>
#include <fcntl.h>
#include <signal.h>
#include <time.h>
#include <sys/time.h>
#include <malloc.h>
#include <termios.h>
#include <sys/poll.h>
#include <errno.h>
#include <sys/wait.h>
#include <netinet/in.h>

#include "cpu.h"
#include "vl.h"

/* debug PC keyboard */
//#define DEBUG_KBD

/* debug PC keyboard : only mouse */
//#define DEBUG_MOUSE

/*	Keyboard Controller Commands */
#define KBD_CCMD_READ_MODE	0x20	/* Read mode bits */
#define KBD_CCMD_WRITE_MODE	0x60	/* Write mode bits */
#define KBD_CCMD_GET_VERSION	0xA1	/* Get controller version */
#define KBD_CCMD_MOUSE_DISABLE	0xA7	/* Disable mouse interface */
#define KBD_CCMD_MOUSE_ENABLE	0xA8	/* Enable mouse interface */
#define KBD_CCMD_TEST_MOUSE	0xA9	/* Mouse interface test */
#define KBD_CCMD_SELF_TEST	0xAA	/* Controller self test */
#define KBD_CCMD_KBD_TEST	0xAB	/* Keyboard interface test */
#define KBD_CCMD_KBD_DISABLE	0xAD	/* Keyboard interface disable */
#define KBD_CCMD_KBD_ENABLE	0xAE	/* Keyboard interface enable */
#define KBD_CCMD_READ_INPORT    0xC0    /* read input port */
#define KBD_CCMD_READ_OUTPORT	0xD0    /* read output port */
#define KBD_CCMD_WRITE_OUTPORT	0xD1    /* write output port */
#define KBD_CCMD_WRITE_OBUF	0xD2
#define KBD_CCMD_WRITE_AUX_OBUF	0xD3    /* Write to output buffer as if
					   initiated by the auxiliary device */
#define KBD_CCMD_WRITE_MOUSE	0xD4	/* Write the following byte to the mouse */
#define KBD_CCMD_DISABLE_A20    0xDD    /* HP vectra only ? */
#define KBD_CCMD_ENABLE_A20     0xDF    /* HP vectra only ? */
#define KBD_CCMD_RESET	        0xFE

/* Keyboard Commands */
#define KBD_CMD_SET_LEDS	0xED	/* Set keyboard leds */
#define KBD_CMD_ECHO     	0xEE
#define KBD_CMD_GET_ID 	        0xF2	/* get keyboard ID */
#define KBD_CMD_SET_RATE	0xF3	/* Set typematic rate */
#define KBD_CMD_ENABLE		0xF4	/* Enable scanning */
#define KBD_CMD_RESET_DISABLE	0xF5	/* reset and disable scanning */
#define KBD_CMD_RESET_ENABLE   	0xF6    /* reset and enable scanning */
#define KBD_CMD_RESET		0xFF	/* Reset */

/* Keyboard Replies */
#define KBD_REPLY_POR		0xAA	/* Power on reset */
#define KBD_REPLY_ACK		0xFA	/* Command ACK */
#define KBD_REPLY_RESEND	0xFE	/* Command NACK, send the cmd again */

/* Status Register Bits */
#define KBD_STAT_OBF 		0x01	/* Keyboard output buffer full */
#define KBD_STAT_IBF 		0x02	/* Keyboard input buffer full */
#define KBD_STAT_SELFTEST	0x04	/* Self test successful */
#define KBD_STAT_CMD		0x08	/* Last write was a command write (0=data) */
#define KBD_STAT_UNLOCKED	0x10	/* Zero if keyboard locked */
#define KBD_STAT_MOUSE_OBF	0x20	/* Mouse output buffer full */
#define KBD_STAT_GTO 		0x40	/* General receive/xmit timeout */
#define KBD_STAT_PERR 		0x80	/* Parity error */

/* Controller Mode Register Bits */
#define KBD_MODE_KBD_INT	0x01	/* Keyboard data generate IRQ1 */
#define KBD_MODE_MOUSE_INT	0x02	/* Mouse data generate IRQ12 */
#define KBD_MODE_SYS 		0x04	/* The system flag (?) */
#define KBD_MODE_NO_KEYLOCK	0x08	/* The keylock doesn't affect the keyboard if set */
#define KBD_MODE_DISABLE_KBD	0x10	/* Disable keyboard interface */
#define KBD_MODE_DISABLE_MOUSE	0x20	/* Disable mouse interface */
#define KBD_MODE_KCC 		0x40	/* Scan code conversion to PC format */
#define KBD_MODE_RFU		0x80

/* Mouse Commands */
#define AUX_SET_SCALE11		0xE6	/* Set 1:1 scaling */
#define AUX_SET_SCALE21		0xE7	/* Set 2:1 scaling */
#define AUX_SET_RES		0xE8	/* Set resolution */
#define AUX_GET_SCALE		0xE9	/* Get scaling factor */
#define AUX_SET_STREAM		0xEA	/* Set stream mode */
#define AUX_POLL		0xEB	/* Poll */
#define AUX_RESET_WRAP		0xEC	/* Reset wrap mode */
#define AUX_SET_WRAP		0xEE	/* Set wrap mode */
#define AUX_SET_REMOTE		0xF0	/* Set remote mode */
#define AUX_GET_TYPE		0xF2	/* Get type */
#define AUX_SET_SAMPLE		0xF3	/* Set sample rate */
#define AUX_ENABLE_DEV		0xF4	/* Enable aux device */
#define AUX_DISABLE_DEV		0xF5	/* Disable aux device */
#define AUX_SET_DEFAULT		0xF6
#define AUX_RESET		0xFF	/* Reset aux device */
#define AUX_ACK			0xFA	/* Command byte ACK. */

#define MOUSE_STATUS_REMOTE     0x40
#define MOUSE_STATUS_ENABLED    0x20
#define MOUSE_STATUS_SCALE21    0x10

#define KBD_QUEUE_SIZE 256

typedef struct {
    uint8_t data[KBD_QUEUE_SIZE];
    int rptr, wptr, count;
} KBDQueue;

typedef struct KBDState {
    KBDQueue queues[2];
    uint8_t write_cmd; /* if non zero, write data to port 60 is expected */
    uint8_t status;
    uint8_t mode;
    /* keyboard state */
    int kbd_write_cmd;
    int scan_enabled;
    /* mouse state */
    int mouse_write_cmd;
    uint8_t mouse_status;
    uint8_t mouse_resolution;
    uint8_t mouse_sample_rate;
    uint8_t mouse_wrap;
    uint8_t mouse_type; /* 0 = PS2, 3 = IMPS/2, 4 = IMEX */
    uint8_t mouse_detect_state;
    int mouse_dx; /* current values, needed for 'poll' mode */
    int mouse_dy;
    int mouse_dz;
    uint8_t mouse_buttons;
} KBDState;

KBDState kbd_state;
int reset_requested;

/* update irq and KBD_STAT_[MOUSE_]OBF */
/* XXX: not generating the irqs if KBD_MODE_DISABLE_KBD is set may be
   incorrect, but it avoids having to simulate exact delays */
static void kbd_update_irq(KBDState *s)
{
    int irq12_level, irq1_level;

    irq1_level = 0;    
    irq12_level = 0;    
    s->status &= ~(KBD_STAT_OBF | KBD_STAT_MOUSE_OBF);
    if (s->queues[0].count != 0 ||
        s->queues[1].count != 0) {
        s->status |= KBD_STAT_OBF;
        if (s->queues[1].count != 0) {
            s->status |= KBD_STAT_MOUSE_OBF;
            if (s->mode & KBD_MODE_MOUSE_INT)
                irq12_level = 1;
        } else {
            if ((s->mode & KBD_MODE_KBD_INT) && 
                !(s->mode & KBD_MODE_DISABLE_KBD))
                irq1_level = 1;
        }
    }
    pic_set_irq(1, irq1_level);
    pic_set_irq(12, irq12_level);
}

static void kbd_queue(KBDState *s, int b, int aux)
{
    KBDQueue *q = &s->queues[aux];

#if defined(DEBUG_MOUSE) || defined(DEBUG_KBD)
    if (aux)
        printf("mouse event: 0x%02x\n", b);
#ifdef DEBUG_KBD
    else
        printf("kbd event: 0x%02x\n", b);
#endif
#endif
    if (q->count >= KBD_QUEUE_SIZE)
        return;
    q->data[q->wptr] = b;
    if (++q->wptr == KBD_QUEUE_SIZE)
        q->wptr = 0;
    q->count++;
    kbd_update_irq(s);
}

void kbd_put_keycode(int keycode)
{
    KBDState *s = &kbd_state;
    kbd_queue(s, keycode, 0);
}

static uint32_t kbd_read_status(void *opaque, uint32_t addr)
{
    KBDState *s = opaque;
    int val;
    val = s->status;
#if defined(DEBUG_KBD)
    printf("kbd: read status=0x%02x\n", val);
#endif
    return val;
}

static void kbd_write_command(void *opaque, uint32_t addr, uint32_t val)
{
    KBDState *s = opaque;

#ifdef DEBUG_KBD
    printf("kbd: write cmd=0x%02x\n", val);
#endif
    switch(val) {
    case KBD_CCMD_READ_MODE:
        kbd_queue(s, s->mode, 0);
        break;
    case KBD_CCMD_WRITE_MODE:
    case KBD_CCMD_WRITE_OBUF:
    case KBD_CCMD_WRITE_AUX_OBUF:
    case KBD_CCMD_WRITE_MOUSE:
    case KBD_CCMD_WRITE_OUTPORT:
        s->write_cmd = val;
        break;
    case KBD_CCMD_MOUSE_DISABLE:
        s->mode |= KBD_MODE_DISABLE_MOUSE;
        break;
    case KBD_CCMD_MOUSE_ENABLE:
        s->mode &= ~KBD_MODE_DISABLE_MOUSE;
        break;
    case KBD_CCMD_TEST_MOUSE:
        kbd_queue(s, 0x00, 0);
        break;
    case KBD_CCMD_SELF_TEST:
        s->status |= KBD_STAT_SELFTEST;
        kbd_queue(s, 0x55, 0);
        break;
    case KBD_CCMD_KBD_TEST:
        kbd_queue(s, 0x00, 0);
        break;
    case KBD_CCMD_KBD_DISABLE:
        s->mode |= KBD_MODE_DISABLE_KBD;
        kbd_update_irq(s);
        break;
    case KBD_CCMD_KBD_ENABLE:
        s->mode &= ~KBD_MODE_DISABLE_KBD;
        kbd_update_irq(s);
        break;
    case KBD_CCMD_READ_INPORT:
        kbd_queue(s, 0x00, 0);
        break;
    case KBD_CCMD_READ_OUTPORT:
        /* XXX: check that */
#ifdef TARGET_I386
        val = 0x01 | (((cpu_single_env->a20_mask >> 20) & 1) << 1);
#else
        val = 0x01;
#endif
        if (s->status & KBD_STAT_OBF)
            val |= 0x10;
        if (s->status & KBD_STAT_MOUSE_OBF)
            val |= 0x20;
        kbd_queue(s, val, 0);
        break;
#ifdef TARGET_I386
    case KBD_CCMD_ENABLE_A20:
        cpu_x86_set_a20(cpu_single_env, 1);
        break;
    case KBD_CCMD_DISABLE_A20:
        cpu_x86_set_a20(cpu_single_env, 0);
        break;
#endif
    case KBD_CCMD_RESET:
        reset_requested = 1;
        cpu_interrupt(cpu_single_env, CPU_INTERRUPT_EXIT);
        break;
    case 0xff:
        /* ignore that - I don't know what is its use */
        break;
    default:
        fprintf(stderr, "qemu: unsupported keyboard cmd=0x%02x\n", val);
        break;
    }
}

static uint32_t kbd_read_data(void *opaque, uint32_t addr)
{
    KBDState *s = opaque;
    KBDQueue *q;
    int val, index;
    
    q = &s->queues[0]; /* first check KBD data */
    if (q->count == 0)
        q = &s->queues[1]; /* then check AUX data */
    if (q->count == 0) {
        /* NOTE: if no data left, we return the last keyboard one
           (needed for EMM386) */
        /* XXX: need a timer to do things correctly */
        q = &s->queues[0];
        index = q->rptr - 1;
        if (index < 0)
            index = KBD_QUEUE_SIZE - 1;
        val = q->data[index];
    } else {
        val = q->data[q->rptr];
        if (++q->rptr == KBD_QUEUE_SIZE)
            q->rptr = 0;
        q->count--;
        /* reading deasserts IRQ */
        if (q == &s->queues[0])
            pic_set_irq(1, 0);
        else
            pic_set_irq(12, 0);
    }
    /* reassert IRQs if data left */
    kbd_update_irq(s);
#ifdef DEBUG_KBD
    printf("kbd: read data=0x%02x\n", val);
#endif
    return val;
}

static void kbd_reset_keyboard(KBDState *s)
{
    s->scan_enabled = 1;
}

static void kbd_write_keyboard(KBDState *s, int val)
{
    switch(s->kbd_write_cmd) {
    default:
    case -1:
        switch(val) {
        case 0x00:
            kbd_queue(s, KBD_REPLY_ACK, 0);
            break;
        case 0x05:
            kbd_queue(s, KBD_REPLY_RESEND, 0);
            break;
        case KBD_CMD_GET_ID:
            kbd_queue(s, KBD_REPLY_ACK, 0);
            kbd_queue(s, 0xab, 0);
            kbd_queue(s, 0x83, 0);
            break;
        case KBD_CMD_ECHO:
            kbd_queue(s, KBD_CMD_ECHO, 0);
            break;
        case KBD_CMD_ENABLE:
            s->scan_enabled = 1;
            kbd_queue(s, KBD_REPLY_ACK, 0);
            break;
        case KBD_CMD_SET_LEDS:
        case KBD_CMD_SET_RATE:
            s->kbd_write_cmd = val;
            kbd_queue(s, KBD_REPLY_ACK, 0);
            break;
        case KBD_CMD_RESET_DISABLE:
            kbd_reset_keyboard(s);
            s->scan_enabled = 0;
            kbd_queue(s, KBD_REPLY_ACK, 0);
            break;
        case KBD_CMD_RESET_ENABLE:
            kbd_reset_keyboard(s);
            s->scan_enabled = 1;
            kbd_queue(s, KBD_REPLY_ACK, 0);
            break;
        case KBD_CMD_RESET:
            kbd_reset_keyboard(s);
            kbd_queue(s, KBD_REPLY_ACK, 0);
            kbd_queue(s, KBD_REPLY_POR, 0);
            break;
        default:
            kbd_queue(s, KBD_REPLY_ACK, 0);
            break;
        }
        break;
    case KBD_CMD_SET_LEDS:
        kbd_queue(s, KBD_REPLY_ACK, 0);
        s->kbd_write_cmd = -1;
        break;
    case KBD_CMD_SET_RATE:
        kbd_queue(s, KBD_REPLY_ACK, 0);
        s->kbd_write_cmd = -1;
        break;
    }
}

static void kbd_mouse_send_packet(KBDState *s)
{
    unsigned int b;
    int dx1, dy1, dz1;

    dx1 = s->mouse_dx;
    dy1 = s->mouse_dy;
    dz1 = s->mouse_dz;
    /* XXX: increase range to 8 bits ? */
    if (dx1 > 127)
        dx1 = 127;
    else if (dx1 < -127)
        dx1 = -127;
    if (dy1 > 127)
        dy1 = 127;
    else if (dy1 < -127)
        dy1 = -127;
    b = 0x08 | ((dx1 < 0) << 4) | ((dy1 < 0) << 5) | (s->mouse_buttons & 0x07);
    kbd_queue(s, b, 1);
    kbd_queue(s, dx1 & 0xff, 1);
    kbd_queue(s, dy1 & 0xff, 1);
    /* extra byte for IMPS/2 or IMEX */
    switch(s->mouse_type) {
    default:
        break;
    case 3:
        if (dz1 > 127)
            dz1 = 127;
        else if (dz1 < -127)
                dz1 = -127;
        kbd_queue(s, dz1 & 0xff, 1);
        break;
    case 4:
        if (dz1 > 7)
            dz1 = 7;
        else if (dz1 < -7)
            dz1 = -7;
        b = (dz1 & 0x0f) | ((s->mouse_buttons & 0x18) << 1);
        kbd_queue(s, b, 1);
        break;
    }

    /* update deltas */
    s->mouse_dx -= dx1;
    s->mouse_dy -= dy1;
    s->mouse_dz -= dz1;
}

void kbd_mouse_event(int dx, int dy, int dz, int buttons_state)
{
    KBDState *s = &kbd_state;

    /* check if deltas are recorded when disabled */
    if (!(s->mouse_status & MOUSE_STATUS_ENABLED))
        return;

    s->mouse_dx += dx;
    s->mouse_dy -= dy;
    s->mouse_dz += dz;
    s->mouse_buttons = buttons_state;
    
    if (!(s->mouse_status & MOUSE_STATUS_REMOTE) &&
        (s->queues[1].count < (KBD_QUEUE_SIZE - 16))) {
        for(;;) {
            /* if not remote, send event. Multiple events are sent if
               too big deltas */
            kbd_mouse_send_packet(s);
            if (s->mouse_dx == 0 && s->mouse_dy == 0 && s->mouse_dz == 0)
                break;
        }
    }
}

static void kbd_write_mouse(KBDState *s, int val)
{
#ifdef DEBUG_MOUSE
    printf("kbd: write mouse 0x%02x\n", val);
#endif
    switch(s->mouse_write_cmd) {
    default:
    case -1:
        /* mouse command */
        if (s->mouse_wrap) {
            if (val == AUX_RESET_WRAP) {
                s->mouse_wrap = 0;
                kbd_queue(s, AUX_ACK, 1);
                return;
            } else if (val != AUX_RESET) {
                kbd_queue(s, val, 1);
                return;
            }
        }
        switch(val) {
        case AUX_SET_SCALE11:
            s->mouse_status &= ~MOUSE_STATUS_SCALE21;
            kbd_queue(s, AUX_ACK, 1);
            break;
        case AUX_SET_SCALE21:
            s->mouse_status |= MOUSE_STATUS_SCALE21;
            kbd_queue(s, AUX_ACK, 1);
            break;
        case AUX_SET_STREAM:
            s->mouse_status &= ~MOUSE_STATUS_REMOTE;
            kbd_queue(s, AUX_ACK, 1);
            break;
        case AUX_SET_WRAP:
            s->mouse_wrap = 1;
            kbd_queue(s, AUX_ACK, 1);
            break;
        case AUX_SET_REMOTE:
            s->mouse_status |= MOUSE_STATUS_REMOTE;
            kbd_queue(s, AUX_ACK, 1);
            break;
        case AUX_GET_TYPE:
            kbd_queue(s, AUX_ACK, 1);
            kbd_queue(s, s->mouse_type, 1);
            break;
        case AUX_SET_RES:
        case AUX_SET_SAMPLE:
            s->mouse_write_cmd = val;
            kbd_queue(s, AUX_ACK, 1);
            break;
        case AUX_GET_SCALE:
            kbd_queue(s, AUX_ACK, 1);
            kbd_queue(s, s->mouse_status, 1);
            kbd_queue(s, s->mouse_resolution, 1);
            kbd_queue(s, s->mouse_sample_rate, 1);
            break;
        case AUX_POLL:
            kbd_queue(s, AUX_ACK, 1);
            kbd_mouse_send_packet(s);
            break;
        case AUX_ENABLE_DEV:
            s->mouse_status |= MOUSE_STATUS_ENABLED;
            kbd_queue(s, AUX_ACK, 1);
            break;
        case AUX_DISABLE_DEV:
            s->mouse_status &= ~MOUSE_STATUS_ENABLED;
            kbd_queue(s, AUX_ACK, 1);
            break;
        case AUX_SET_DEFAULT:
            s->mouse_sample_rate = 100;
            s->mouse_resolution = 2;
            s->mouse_status = 0;
            kbd_queue(s, AUX_ACK, 1);
            break;
        case AUX_RESET:
            s->mouse_sample_rate = 100;
            s->mouse_resolution = 2;
            s->mouse_status = 0;
            kbd_queue(s, AUX_ACK, 1);
            kbd_queue(s, 0xaa, 1);
            kbd_queue(s, s->mouse_type, 1);
            break;
        default:
            break;
        }
        break;
    case AUX_SET_SAMPLE:
        s->mouse_sample_rate = val;
#if 0
        /* detect IMPS/2 or IMEX */
        switch(s->mouse_detect_state) {
        default:
        case 0:
            if (val == 200)
                s->mouse_detect_state = 1;
            break;
        case 1:
            if (val == 100)
                s->mouse_detect_state = 2;
            else if (val == 200)
                s->mouse_detect_state = 3;
            else
                s->mouse_detect_state = 0;
            break;
        case 2:
            if (val == 80) 
                s->mouse_type = 3; /* IMPS/2 */
            s->mouse_detect_state = 0;
            break;
        case 3:
            if (val == 80) 
                s->mouse_type = 4; /* IMEX */
            s->mouse_detect_state = 0;
            break;
        }
#endif
        kbd_queue(s, AUX_ACK, 1);
        s->mouse_write_cmd = -1;
        break;
    case AUX_SET_RES:
        s->mouse_resolution = val;
        kbd_queue(s, AUX_ACK, 1);
        s->mouse_write_cmd = -1;
        break;
    }
}

void kbd_write_data(void *opaque, uint32_t addr, uint32_t val)
{
    KBDState *s = opaque;

#ifdef DEBUG_KBD
    printf("kbd: write data=0x%02x\n", val);
#endif

    switch(s->write_cmd) {
    case 0:
        kbd_write_keyboard(s, val);
        break;
    case KBD_CCMD_WRITE_MODE:
        s->mode = val;
        kbd_update_irq(s);
        break;
    case KBD_CCMD_WRITE_OBUF:
        kbd_queue(s, val, 0);
        break;
    case KBD_CCMD_WRITE_AUX_OBUF:
        kbd_queue(s, val, 1);
        break;
    case KBD_CCMD_WRITE_OUTPORT:
#ifdef TARGET_I386
        cpu_x86_set_a20(cpu_single_env, (val >> 1) & 1);
#endif
        if (!(val & 1)) {
            reset_requested = 1;
            cpu_interrupt(cpu_single_env, CPU_INTERRUPT_EXIT);
        }
        break;
    case KBD_CCMD_WRITE_MOUSE:
        kbd_write_mouse(s, val);
        break;
    default:
        break;
    }
    s->write_cmd = 0;
}

void kbd_reset(KBDState *s)
{
    KBDQueue *q;
    int i;

    s->kbd_write_cmd = -1;
    s->mouse_write_cmd = -1;
    s->mode = KBD_MODE_KBD_INT | KBD_MODE_MOUSE_INT;
    s->status = KBD_STAT_CMD | KBD_STAT_UNLOCKED;
    for(i = 0; i < 2; i++) {
        q = &s->queues[i];
        q->rptr = 0;
        q->wptr = 0;
        q->count = 0;
    }
}

void kbd_init(void)
{
    KBDState *s = &kbd_state;
    
    kbd_reset(s);
    register_ioport_read(0x60, 1, 1, kbd_read_data, s);
    register_ioport_write(0x60, 1, 1, kbd_write_data, s);
    register_ioport_read(0x64, 1, 1, kbd_read_status, s);
    register_ioport_write(0x64, 1, 1, kbd_write_command, s);
}