Merge remote-tracking branch 'bonzini/tags/for-upstream' into staging

[qemu.git] / hw / input / adb.c

/*
 * QEMU ADB support
 *
 * Copyright (c) 2004 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 "qemu/osdep.h"
#include "hw/hw.h"
#include "hw/input/adb.h"
#include "ui/console.h"
#include "include/hw/input/adb-keys.h"
#include "ui/input.h"
#include "sysemu/sysemu.h"

/* debug ADB */
//#define DEBUG_ADB

#ifdef DEBUG_ADB
#define ADB_DPRINTF(fmt, ...) \
do { printf("ADB: " fmt , ## __VA_ARGS__); } while (0)
#else
#define ADB_DPRINTF(fmt, ...)
#endif

/* ADB commands */
#define ADB_BUSRESET		0x00
#define ADB_FLUSH               0x01
#define ADB_WRITEREG		0x08
#define ADB_READREG		0x0c

/* ADB device commands */
#define ADB_CMD_SELF_TEST		0xff
#define ADB_CMD_CHANGE_ID		0xfe
#define ADB_CMD_CHANGE_ID_AND_ACT	0xfd
#define ADB_CMD_CHANGE_ID_AND_ENABLE	0x00

/* ADB default device IDs (upper 4 bits of ADB command byte) */
#define ADB_DEVID_DONGLE   1
#define ADB_DEVID_KEYBOARD 2
#define ADB_DEVID_MOUSE    3
#define ADB_DEVID_TABLET   4
#define ADB_DEVID_MODEM    5
#define ADB_DEVID_MISC     7

/* error codes */
#define ADB_RET_NOTPRESENT (-2)

/* The adb keyboard doesn't have every key imaginable */
#define NO_KEY 0xff

static void adb_device_reset(ADBDevice *d)
{
    qdev_reset_all(DEVICE(d));
}

int adb_request(ADBBusState *s, uint8_t *obuf, const uint8_t *buf, int len)
{
    ADBDevice *d;
    int devaddr, cmd, i;

    cmd = buf[0] & 0xf;
    if (cmd == ADB_BUSRESET) {
        for(i = 0; i < s->nb_devices; i++) {
            d = s->devices[i];
            adb_device_reset(d);
        }
        return 0;
    }
    devaddr = buf[0] >> 4;
    for(i = 0; i < s->nb_devices; i++) {
        d = s->devices[i];
        if (d->devaddr == devaddr) {
            ADBDeviceClass *adc = ADB_DEVICE_GET_CLASS(d);
            return adc->devreq(d, obuf, buf, len);
        }
    }
    return ADB_RET_NOTPRESENT;
}

/* XXX: move that to cuda ? */
int adb_poll(ADBBusState *s, uint8_t *obuf, uint16_t poll_mask)
{
    ADBDevice *d;
    int olen, i;
    uint8_t buf[1];

    olen = 0;
    for(i = 0; i < s->nb_devices; i++) {
        if (s->poll_index >= s->nb_devices)
            s->poll_index = 0;
        d = s->devices[s->poll_index];
        if ((1 << d->devaddr) & poll_mask) {
            buf[0] = ADB_READREG | (d->devaddr << 4);
            olen = adb_request(s, obuf + 1, buf, 1);
            /* if there is data, we poll again the same device */
            if (olen > 0) {
                obuf[0] = buf[0];
                olen++;
                break;
            }
        }
        s->poll_index++;
    }
    return olen;
}

static const TypeInfo adb_bus_type_info = {
    .name = TYPE_ADB_BUS,
    .parent = TYPE_BUS,
    .instance_size = sizeof(ADBBusState),
};

static const VMStateDescription vmstate_adb_device = {
    .name = "adb_device",
    .version_id = 0,
    .minimum_version_id = 0,
    .fields = (VMStateField[]) {
        VMSTATE_INT32(devaddr, ADBDevice),
        VMSTATE_INT32(handler, ADBDevice),
        VMSTATE_END_OF_LIST()
    }
};

static void adb_device_realizefn(DeviceState *dev, Error **errp)
{
    ADBDevice *d = ADB_DEVICE(dev);
    ADBBusState *bus = ADB_BUS(qdev_get_parent_bus(dev));

    if (bus->nb_devices >= MAX_ADB_DEVICES) {
        return;
    }

    bus->devices[bus->nb_devices++] = d;
}

static void adb_device_class_init(ObjectClass *oc, void *data)
{
    DeviceClass *dc = DEVICE_CLASS(oc);

    dc->realize = adb_device_realizefn;
    dc->bus_type = TYPE_ADB_BUS;
}

static const TypeInfo adb_device_type_info = {
    .name = TYPE_ADB_DEVICE,
    .parent = TYPE_DEVICE,
    .instance_size = sizeof(ADBDevice),
    .abstract = true,
    .class_init = adb_device_class_init,
};

/***************************************************************/
/* Keyboard ADB device */

#define ADB_KEYBOARD(obj) OBJECT_CHECK(KBDState, (obj), TYPE_ADB_KEYBOARD)

typedef struct KBDState {
    /*< private >*/
    ADBDevice parent_obj;
    /*< public >*/

    uint8_t data[128];
    int rptr, wptr, count;
} KBDState;

#define ADB_KEYBOARD_CLASS(class) \
    OBJECT_CLASS_CHECK(ADBKeyboardClass, (class), TYPE_ADB_KEYBOARD)
#define ADB_KEYBOARD_GET_CLASS(obj) \
    OBJECT_GET_CLASS(ADBKeyboardClass, (obj), TYPE_ADB_KEYBOARD)

typedef struct ADBKeyboardClass {
    /*< private >*/
    ADBDeviceClass parent_class;
    /*< public >*/

    DeviceRealize parent_realize;
} ADBKeyboardClass;

int qcode_to_adb_keycode[] = {
     /* Make sure future additions are automatically set to NO_KEY */
    [0 ... 0xff]               = NO_KEY,

    [Q_KEY_CODE_SHIFT]         = ADB_KEY_LEFT_SHIFT,
    [Q_KEY_CODE_SHIFT_R]       = ADB_KEY_RIGHT_SHIFT,
    [Q_KEY_CODE_ALT]           = ADB_KEY_LEFT_OPTION,
    [Q_KEY_CODE_ALT_R]         = ADB_KEY_RIGHT_OPTION,
    [Q_KEY_CODE_ALTGR]         = ADB_KEY_RIGHT_OPTION,
    [Q_KEY_CODE_CTRL]          = ADB_KEY_LEFT_CONTROL,
    [Q_KEY_CODE_CTRL_R]        = ADB_KEY_RIGHT_CONTROL,
    [Q_KEY_CODE_META_L]        = ADB_KEY_COMMAND,
    [Q_KEY_CODE_META_R]        = ADB_KEY_COMMAND,
    [Q_KEY_CODE_SPC]           = ADB_KEY_SPACEBAR,

    [Q_KEY_CODE_ESC]           = ADB_KEY_ESC,
    [Q_KEY_CODE_1]             = ADB_KEY_1,
    [Q_KEY_CODE_2]             = ADB_KEY_2,
    [Q_KEY_CODE_3]             = ADB_KEY_3,
    [Q_KEY_CODE_4]             = ADB_KEY_4,
    [Q_KEY_CODE_5]             = ADB_KEY_5,
    [Q_KEY_CODE_6]             = ADB_KEY_6,
    [Q_KEY_CODE_7]             = ADB_KEY_7,
    [Q_KEY_CODE_8]             = ADB_KEY_8,
    [Q_KEY_CODE_9]             = ADB_KEY_9,
    [Q_KEY_CODE_0]             = ADB_KEY_0,
    [Q_KEY_CODE_MINUS]         = ADB_KEY_MINUS,
    [Q_KEY_CODE_EQUAL]         = ADB_KEY_EQUAL,
    [Q_KEY_CODE_BACKSPACE]     = ADB_KEY_DELETE,
    [Q_KEY_CODE_TAB]           = ADB_KEY_TAB,
    [Q_KEY_CODE_Q]             = ADB_KEY_Q,
    [Q_KEY_CODE_W]             = ADB_KEY_W,
    [Q_KEY_CODE_E]             = ADB_KEY_E,
    [Q_KEY_CODE_R]             = ADB_KEY_R,
    [Q_KEY_CODE_T]             = ADB_KEY_T,
    [Q_KEY_CODE_Y]             = ADB_KEY_Y,
    [Q_KEY_CODE_U]             = ADB_KEY_U,
    [Q_KEY_CODE_I]             = ADB_KEY_I,
    [Q_KEY_CODE_O]             = ADB_KEY_O,
    [Q_KEY_CODE_P]             = ADB_KEY_P,
    [Q_KEY_CODE_BRACKET_LEFT]  = ADB_KEY_LEFT_BRACKET,
    [Q_KEY_CODE_BRACKET_RIGHT] = ADB_KEY_RIGHT_BRACKET,
    [Q_KEY_CODE_RET]           = ADB_KEY_RETURN,
    [Q_KEY_CODE_A]             = ADB_KEY_A,
    [Q_KEY_CODE_S]             = ADB_KEY_S,
    [Q_KEY_CODE_D]             = ADB_KEY_D,
    [Q_KEY_CODE_F]             = ADB_KEY_F,
    [Q_KEY_CODE_G]             = ADB_KEY_G,
    [Q_KEY_CODE_H]             = ADB_KEY_H,
    [Q_KEY_CODE_J]             = ADB_KEY_J,
    [Q_KEY_CODE_K]             = ADB_KEY_K,
    [Q_KEY_CODE_L]             = ADB_KEY_L,
    [Q_KEY_CODE_SEMICOLON]     = ADB_KEY_SEMICOLON,
    [Q_KEY_CODE_APOSTROPHE]    = ADB_KEY_APOSTROPHE,
    [Q_KEY_CODE_GRAVE_ACCENT]  = ADB_KEY_GRAVE_ACCENT,
    [Q_KEY_CODE_BACKSLASH]     = ADB_KEY_BACKSLASH,
    [Q_KEY_CODE_Z]             = ADB_KEY_Z,
    [Q_KEY_CODE_X]             = ADB_KEY_X,
    [Q_KEY_CODE_C]             = ADB_KEY_C,
    [Q_KEY_CODE_V]             = ADB_KEY_V,
    [Q_KEY_CODE_B]             = ADB_KEY_B,
    [Q_KEY_CODE_N]             = ADB_KEY_N,
    [Q_KEY_CODE_M]             = ADB_KEY_M,
    [Q_KEY_CODE_COMMA]         = ADB_KEY_COMMA,
    [Q_KEY_CODE_DOT]           = ADB_KEY_PERIOD,
    [Q_KEY_CODE_SLASH]         = ADB_KEY_FORWARD_SLASH,
    [Q_KEY_CODE_ASTERISK]      = ADB_KEY_KP_MULTIPLY,
    [Q_KEY_CODE_CAPS_LOCK]     = ADB_KEY_CAPS_LOCK,

    [Q_KEY_CODE_F1]            = ADB_KEY_F1,
    [Q_KEY_CODE_F2]            = ADB_KEY_F2,
    [Q_KEY_CODE_F3]            = ADB_KEY_F3,
    [Q_KEY_CODE_F4]            = ADB_KEY_F4,
    [Q_KEY_CODE_F5]            = ADB_KEY_F5,
    [Q_KEY_CODE_F6]            = ADB_KEY_F6,
    [Q_KEY_CODE_F7]            = ADB_KEY_F7,
    [Q_KEY_CODE_F8]            = ADB_KEY_F8,
    [Q_KEY_CODE_F9]            = ADB_KEY_F9,
    [Q_KEY_CODE_F10]           = ADB_KEY_F10,
    [Q_KEY_CODE_F11]           = ADB_KEY_F11,
    [Q_KEY_CODE_F12]           = ADB_KEY_F12,
    [Q_KEY_CODE_PRINT]         = ADB_KEY_F13,
    [Q_KEY_CODE_SYSRQ]         = ADB_KEY_F13,
    [Q_KEY_CODE_SCROLL_LOCK]   = ADB_KEY_F14,
    [Q_KEY_CODE_PAUSE]         = ADB_KEY_F15,

    [Q_KEY_CODE_NUM_LOCK]      = ADB_KEY_KP_CLEAR,
    [Q_KEY_CODE_KP_EQUALS]     = ADB_KEY_KP_EQUAL,
    [Q_KEY_CODE_KP_DIVIDE]     = ADB_KEY_KP_DIVIDE,
    [Q_KEY_CODE_KP_MULTIPLY]   = ADB_KEY_KP_MULTIPLY,
    [Q_KEY_CODE_KP_SUBTRACT]   = ADB_KEY_KP_SUBTRACT,
    [Q_KEY_CODE_KP_ADD]        = ADB_KEY_KP_PLUS,
    [Q_KEY_CODE_KP_ENTER]      = ADB_KEY_KP_ENTER,
    [Q_KEY_CODE_KP_DECIMAL]    = ADB_KEY_KP_PERIOD,
    [Q_KEY_CODE_KP_0]          = ADB_KEY_KP_0,
    [Q_KEY_CODE_KP_1]          = ADB_KEY_KP_1,
    [Q_KEY_CODE_KP_2]          = ADB_KEY_KP_2,
    [Q_KEY_CODE_KP_3]          = ADB_KEY_KP_3,
    [Q_KEY_CODE_KP_4]          = ADB_KEY_KP_4,
    [Q_KEY_CODE_KP_5]          = ADB_KEY_KP_5,
    [Q_KEY_CODE_KP_6]          = ADB_KEY_KP_6,
    [Q_KEY_CODE_KP_7]          = ADB_KEY_KP_7,
    [Q_KEY_CODE_KP_8]          = ADB_KEY_KP_8,
    [Q_KEY_CODE_KP_9]          = ADB_KEY_KP_9,

    [Q_KEY_CODE_UP]            = ADB_KEY_UP,
    [Q_KEY_CODE_DOWN]          = ADB_KEY_DOWN,
    [Q_KEY_CODE_LEFT]          = ADB_KEY_LEFT,
    [Q_KEY_CODE_RIGHT]         = ADB_KEY_RIGHT,

    [Q_KEY_CODE_HELP]          = ADB_KEY_HELP,
    [Q_KEY_CODE_INSERT]        = ADB_KEY_HELP,
    [Q_KEY_CODE_DELETE]        = ADB_KEY_FORWARD_DELETE,
    [Q_KEY_CODE_HOME]          = ADB_KEY_HOME,
    [Q_KEY_CODE_END]           = ADB_KEY_END,
    [Q_KEY_CODE_PGUP]          = ADB_KEY_PAGE_UP,
    [Q_KEY_CODE_PGDN]          = ADB_KEY_PAGE_DOWN,

    [Q_KEY_CODE_POWER]         = ADB_KEY_POWER
};

static void adb_kbd_put_keycode(void *opaque, int keycode)
{
    KBDState *s = opaque;

    if (s->count < sizeof(s->data)) {
        s->data[s->wptr] = keycode;
        if (++s->wptr == sizeof(s->data))
            s->wptr = 0;
        s->count++;
    }
}

static int adb_kbd_poll(ADBDevice *d, uint8_t *obuf)
{
    KBDState *s = ADB_KEYBOARD(d);
    int keycode;
    int olen;

    olen = 0;
    if (s->count == 0) {
        return 0;
    }
    keycode = s->data[s->rptr];
    s->rptr++;
    if (s->rptr == sizeof(s->data)) {
        s->rptr = 0;
    }
    s->count--;
    /*
     * The power key is the only two byte value key, so it is a special case.
     * Since 0x7f is not a used keycode for ADB we overload it to indicate the
     * power button when we're storing keycodes in our internal buffer, and
     * expand it out to two bytes when we send to the guest.
     */
    if (keycode == 0x7f) {
        obuf[0] = 0x7f;
        obuf[1] = 0x7f;
        olen = 2;
    } else {
        obuf[0] = keycode;
        /* NOTE: the power key key-up is the two byte sequence 0xff 0xff;
         * otherwise we could in theory send a second keycode in the second
         * byte, but choose not to bother.
         */
        obuf[1] = 0xff;
        olen = 2;
    }

    return olen;
}

static int adb_kbd_request(ADBDevice *d, uint8_t *obuf,
                           const uint8_t *buf, int len)
{
    KBDState *s = ADB_KEYBOARD(d);
    int cmd, reg, olen;

    if ((buf[0] & 0x0f) == ADB_FLUSH) {
        /* flush keyboard fifo */
        s->wptr = s->rptr = s->count = 0;
        return 0;
    }

    cmd = buf[0] & 0xc;
    reg = buf[0] & 0x3;
    olen = 0;
    switch(cmd) {
    case ADB_WRITEREG:
        switch(reg) {
        case 2:
            /* LED status */
            break;
        case 3:
            switch(buf[2]) {
            case ADB_CMD_SELF_TEST:
                break;
            case ADB_CMD_CHANGE_ID:
            case ADB_CMD_CHANGE_ID_AND_ACT:
            case ADB_CMD_CHANGE_ID_AND_ENABLE:
                d->devaddr = buf[1] & 0xf;
                break;
            default:
                d->devaddr = buf[1] & 0xf;
                /* we support handlers:
                 * 1: Apple Standard Keyboard
                 * 2: Apple Extended Keyboard (LShift = RShift)
                 * 3: Apple Extended Keyboard (LShift != RShift)
                 */
                if (buf[2] == 1 || buf[2] == 2 || buf[2] == 3) {
                    d->handler = buf[2];
                }
                break;
            }
        }
        break;
    case ADB_READREG:
        switch(reg) {
        case 0:
            olen = adb_kbd_poll(d, obuf);
            break;
        case 1:
            break;
        case 2:
            obuf[0] = 0x00; /* XXX: check this */
            obuf[1] = 0x07; /* led status */
            olen = 2;
            break;
        case 3:
            obuf[0] = d->handler;
            obuf[1] = d->devaddr;
            olen = 2;
            break;
        }
        break;
    }
    return olen;
}

/* This is where keyboard events enter this file */
static void adb_keyboard_event(DeviceState *dev, QemuConsole *src,
                               InputEvent *evt)
{
    KBDState *s = (KBDState *)dev;
    int qcode, keycode;

    qcode = qemu_input_key_value_to_qcode(evt->u.key.data->key);
    if (qcode >= ARRAY_SIZE(qcode_to_adb_keycode)) {
        return;
    }
    /* FIXME: take handler into account when translating qcode */
    keycode = qcode_to_adb_keycode[qcode];
    if (keycode == NO_KEY) {  /* We don't want to send this to the guest */
        ADB_DPRINTF("Ignoring NO_KEY\n");
        return;
    }
    if (evt->u.key.data->down == false) { /* if key release event */
        keycode = keycode | 0x80;   /* create keyboard break code */
    }

    adb_kbd_put_keycode(s, keycode);
}

static const VMStateDescription vmstate_adb_kbd = {
    .name = "adb_kbd",
    .version_id = 2,
    .minimum_version_id = 2,
    .fields = (VMStateField[]) {
        VMSTATE_STRUCT(parent_obj, KBDState, 0, vmstate_adb_device, ADBDevice),
        VMSTATE_BUFFER(data, KBDState),
        VMSTATE_INT32(rptr, KBDState),
        VMSTATE_INT32(wptr, KBDState),
        VMSTATE_INT32(count, KBDState),
        VMSTATE_END_OF_LIST()
    }
};

static void adb_kbd_reset(DeviceState *dev)
{
    ADBDevice *d = ADB_DEVICE(dev);
    KBDState *s = ADB_KEYBOARD(dev);

    d->handler = 1;
    d->devaddr = ADB_DEVID_KEYBOARD;
    memset(s->data, 0, sizeof(s->data));
    s->rptr = 0;
    s->wptr = 0;
    s->count = 0;
}

static QemuInputHandler adb_keyboard_handler = {
    .name  = "QEMU ADB Keyboard",
    .mask  = INPUT_EVENT_MASK_KEY,
    .event = adb_keyboard_event,
};

static void adb_kbd_realizefn(DeviceState *dev, Error **errp)
{
    ADBKeyboardClass *akc = ADB_KEYBOARD_GET_CLASS(dev);
    akc->parent_realize(dev, errp);
    qemu_input_handler_register(dev, &adb_keyboard_handler);
}

static void adb_kbd_initfn(Object *obj)
{
    ADBDevice *d = ADB_DEVICE(obj);

    d->devaddr = ADB_DEVID_KEYBOARD;
}

static void adb_kbd_class_init(ObjectClass *oc, void *data)
{
    DeviceClass *dc = DEVICE_CLASS(oc);
    ADBDeviceClass *adc = ADB_DEVICE_CLASS(oc);
    ADBKeyboardClass *akc = ADB_KEYBOARD_CLASS(oc);

    akc->parent_realize = dc->realize;
    dc->realize = adb_kbd_realizefn;
    set_bit(DEVICE_CATEGORY_INPUT, dc->categories);

    adc->devreq = adb_kbd_request;
    dc->reset = adb_kbd_reset;
    dc->vmsd = &vmstate_adb_kbd;
}

static const TypeInfo adb_kbd_type_info = {
    .name = TYPE_ADB_KEYBOARD,
    .parent = TYPE_ADB_DEVICE,
    .instance_size = sizeof(KBDState),
    .instance_init = adb_kbd_initfn,
    .class_init = adb_kbd_class_init,
    .class_size = sizeof(ADBKeyboardClass),
};

/***************************************************************/
/* Mouse ADB device */

#define ADB_MOUSE(obj) OBJECT_CHECK(MouseState, (obj), TYPE_ADB_MOUSE)

typedef struct MouseState {
    /*< public >*/
    ADBDevice parent_obj;
    /*< private >*/

    int buttons_state, last_buttons_state;
    int dx, dy, dz;
} MouseState;

#define ADB_MOUSE_CLASS(class) \
    OBJECT_CLASS_CHECK(ADBMouseClass, (class), TYPE_ADB_MOUSE)
#define ADB_MOUSE_GET_CLASS(obj) \
    OBJECT_GET_CLASS(ADBMouseClass, (obj), TYPE_ADB_MOUSE)

typedef struct ADBMouseClass {
    /*< public >*/
    ADBDeviceClass parent_class;
    /*< private >*/

    DeviceRealize parent_realize;
} ADBMouseClass;

static void adb_mouse_event(void *opaque,
                            int dx1, int dy1, int dz1, int buttons_state)
{
    MouseState *s = opaque;

    s->dx += dx1;
    s->dy += dy1;
    s->dz += dz1;
    s->buttons_state = buttons_state;
}


static int adb_mouse_poll(ADBDevice *d, uint8_t *obuf)
{
    MouseState *s = ADB_MOUSE(d);
    int dx, dy;

    if (s->last_buttons_state == s->buttons_state &&
        s->dx == 0 && s->dy == 0)
        return 0;

    dx = s->dx;
    if (dx < -63)
        dx = -63;
    else if (dx > 63)
        dx = 63;

    dy = s->dy;
    if (dy < -63)
        dy = -63;
    else if (dy > 63)
        dy = 63;

    s->dx -= dx;
    s->dy -= dy;
    s->last_buttons_state = s->buttons_state;

    dx &= 0x7f;
    dy &= 0x7f;

    if (!(s->buttons_state & MOUSE_EVENT_LBUTTON))
        dy |= 0x80;
    if (!(s->buttons_state & MOUSE_EVENT_RBUTTON))
        dx |= 0x80;

    obuf[0] = dy;
    obuf[1] = dx;
    return 2;
}

static int adb_mouse_request(ADBDevice *d, uint8_t *obuf,
                             const uint8_t *buf, int len)
{
    MouseState *s = ADB_MOUSE(d);
    int cmd, reg, olen;

    if ((buf[0] & 0x0f) == ADB_FLUSH) {
        /* flush mouse fifo */
        s->buttons_state = s->last_buttons_state;
        s->dx = 0;
        s->dy = 0;
        s->dz = 0;
        return 0;
    }

    cmd = buf[0] & 0xc;
    reg = buf[0] & 0x3;
    olen = 0;
    switch(cmd) {
    case ADB_WRITEREG:
        ADB_DPRINTF("write reg %d val 0x%2.2x\n", reg, buf[1]);
        switch(reg) {
        case 2:
            break;
        case 3:
            switch(buf[2]) {
            case ADB_CMD_SELF_TEST:
                break;
            case ADB_CMD_CHANGE_ID:
            case ADB_CMD_CHANGE_ID_AND_ACT:
            case ADB_CMD_CHANGE_ID_AND_ENABLE:
                d->devaddr = buf[1] & 0xf;
                break;
            default:
                d->devaddr = buf[1] & 0xf;
                /* we support handlers:
                 * 0x01: Classic Apple Mouse Protocol / 100 cpi operations
                 * 0x02: Classic Apple Mouse Protocol / 200 cpi operations
                 * we don't support handlers (at least):
                 * 0x03: Mouse systems A3 trackball
                 * 0x04: Extended Apple Mouse Protocol
                 * 0x2f: Microspeed mouse
                 * 0x42: Macally
                 * 0x5f: Microspeed mouse
                 * 0x66: Microspeed mouse
                 */
                if (buf[2] == 1 || buf[2] == 2) {
                    d->handler = buf[2];
                }
                break;
            }
        }
        break;
    case ADB_READREG:
        switch(reg) {
        case 0:
            olen = adb_mouse_poll(d, obuf);
            break;
        case 1:
            break;
        case 3:
            obuf[0] = d->handler;
            obuf[1] = d->devaddr;
            olen = 2;
            break;
        }
        ADB_DPRINTF("read reg %d obuf[0] 0x%2.2x obuf[1] 0x%2.2x\n", reg,
                    obuf[0], obuf[1]);
        break;
    }
    return olen;
}

static void adb_mouse_reset(DeviceState *dev)
{
    ADBDevice *d = ADB_DEVICE(dev);
    MouseState *s = ADB_MOUSE(dev);

    d->handler = 2;
    d->devaddr = ADB_DEVID_MOUSE;
    s->last_buttons_state = s->buttons_state = 0;
    s->dx = s->dy = s->dz = 0;
}

static const VMStateDescription vmstate_adb_mouse = {
    .name = "adb_mouse",
    .version_id = 2,
    .minimum_version_id = 2,
    .fields = (VMStateField[]) {
        VMSTATE_STRUCT(parent_obj, MouseState, 0, vmstate_adb_device,
                       ADBDevice),
        VMSTATE_INT32(buttons_state, MouseState),
        VMSTATE_INT32(last_buttons_state, MouseState),
        VMSTATE_INT32(dx, MouseState),
        VMSTATE_INT32(dy, MouseState),
        VMSTATE_INT32(dz, MouseState),
        VMSTATE_END_OF_LIST()
    }
};

static void adb_mouse_realizefn(DeviceState *dev, Error **errp)
{
    MouseState *s = ADB_MOUSE(dev);
    ADBMouseClass *amc = ADB_MOUSE_GET_CLASS(dev);

    amc->parent_realize(dev, errp);

    qemu_add_mouse_event_handler(adb_mouse_event, s, 0, "QEMU ADB Mouse");
}

static void adb_mouse_initfn(Object *obj)
{
    ADBDevice *d = ADB_DEVICE(obj);

    d->devaddr = ADB_DEVID_MOUSE;
}

static void adb_mouse_class_init(ObjectClass *oc, void *data)
{
    DeviceClass *dc = DEVICE_CLASS(oc);
    ADBDeviceClass *adc = ADB_DEVICE_CLASS(oc);
    ADBMouseClass *amc = ADB_MOUSE_CLASS(oc);

    amc->parent_realize = dc->realize;
    dc->realize = adb_mouse_realizefn;
    set_bit(DEVICE_CATEGORY_INPUT, dc->categories);

    adc->devreq = adb_mouse_request;
    dc->reset = adb_mouse_reset;
    dc->vmsd = &vmstate_adb_mouse;
}

static const TypeInfo adb_mouse_type_info = {
    .name = TYPE_ADB_MOUSE,
    .parent = TYPE_ADB_DEVICE,
    .instance_size = sizeof(MouseState),
    .instance_init = adb_mouse_initfn,
    .class_init = adb_mouse_class_init,
    .class_size = sizeof(ADBMouseClass),
};


static void adb_register_types(void)
{
    type_register_static(&adb_bus_type_info);
    type_register_static(&adb_device_type_info);
    type_register_static(&adb_kbd_type_info);
    type_register_static(&adb_mouse_type_info);
}

type_init(adb_register_types)