/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * 3-Byte Mouse Protocol
 */

#include <sys/param.h>
#include <sys/stream.h>
#include <sys/strsun.h>
#include <sys/vuid_event.h>
#include "vuidmice.h"

#define VUID_BUT(b)             BUT((b*2)+1)

/*
 * VUID_BUT(0)  BUT(1)          LEFT  BUTTON
 * VUID_BUT(1)  BUT(3)          RIGHT BUTTON
 */

#define MOUSE_BUTTON_L          (uchar_t)(0x20) /* Left button pressed  */
#define MOUSE_BUTTON_R          (uchar_t)(0x10) /* Right button pressed */

#define MOUSE_START_CODE        (uchar_t)(0x40) /* Start code in char   */

#define MOUSE_START             0               /* Beginning of packet  */
#define MOUSE_BUTTON            1               /* Got button status    */
#define MOUSE_DELTA_X           2               /* got delta X          */

extern void VUID_PUTNEXT(queue_t *const, uchar_t, uchar_t, uchar_t, int);

int
VUID_OPEN(queue_t *const qp)
{
        STATEP->nbuttons = 2;

        return (0);
}

static void
vuidm3p_sendButtonEvent(queue_t *const qp)
{
        int b;

        if ((STATEP->buttons == 0x30) && (!STATEP->oldbuttons)) {
                /*
                 * both buttons going down simultaneously means button
                 * two going down
                 */
                vuidm3p_putnext(qp, (uchar_t)MS_MIDDLE, FE_PAIR_NONE, 0, 1);
                return;
        } else if ((!STATEP->buttons) && (STATEP->oldbuttons == 0x30)) {
                /*
                 * both buttons going up simultaneously means button
                 * two going up
                 */
                vuidm3p_putnext(qp, (uchar_t)MS_MIDDLE, FE_PAIR_NONE, 0, 0);
                return;
        }

        /*
         * for each button, see if it has changed
         */
        for (b = 0; b < 2; b++) {
                uchar_t mask = 0x20 >> b;

                if ((STATEP->buttons & mask) != (STATEP->oldbuttons & mask))
                        VUID_PUTNEXT(qp, VUID_BUT(b), FE_PAIR_NONE, 0,
                            (STATEP->buttons & mask ? 1 : 0));
        }
}

void
vuidm3p(queue_t *const qp, mblk_t *mp)
{
        int r, code;
        uchar_t *bufp;

        bufp = mp->b_rptr;
        r = MBLKL(mp);

        for (r--; r >= 0; r--) {
                code = *bufp++;

                /* strip the high-order bit (mouse sends 7-bit data) */
                code &= 0x7f;

                switch (STATEP->state) {

                /*
                 * Start state. We stay here if the start code is not
                 * received thus forcing us back into sync. When we
                 * get a start code the button mask comes with it
                 * forcing us to the next state.
                 */

                default:
                case MOUSE_START:
start_code:
                        STATEP->deltax = STATEP->deltay = 0;

                        /* look for sync */
                        if ((code & MOUSE_START_CODE) == 0)
                                break;

                        STATEP->buttons = code & 0x30;

                        if (STATEP->buttons != STATEP->oldbuttons) {
                                vuidm3p_sendButtonEvent(qp);
                                /*
                                 * remember state
                                 */
                                STATEP->oldbuttons = STATEP->buttons;
                        }

                        /*
                         * bits 0 & 1 are bits 6 & 7 of X value
                         * (Sign extend them with the cast.)
                         */
                        STATEP->deltax = (signed char)((code & 0x03) << 6);

                        /*
                         * bits 2 & 3 are bits 6 & 7 of Y value
                         * (Sign extend them with the cast.)
                         */
                        STATEP->deltay = (signed char)((code & 0x0c) << 4);

                        /*
                         * go to the next state
                         */
                        STATEP->state = MOUSE_BUTTON;
                        break;

                        /*
                         * We receive the remaining 6 bits of delta x, forcing
                         * us to the next state. We just piece the value of
                         * delta x together.
                         */
                case MOUSE_BUTTON:
                        if (code & MOUSE_START_CODE) {
                                STATEP->state = MOUSE_START;
                                goto start_code;        /* restart */
                        }

                        STATEP->deltax |= code & 0x3f;
                        STATEP->state = MOUSE_DELTA_X;
                        break;

                        /*
                         * The last part of delta Y, and the packet
                         * *may be* complete
                         */
                case MOUSE_DELTA_X:
                        if (code & MOUSE_START_CODE) {
                                STATEP->state = MOUSE_START;
                                goto start_code;        /* restart */
                        }

                        STATEP->deltay |= code & 0x3f;

                        /*
                         * generate motion Event
                         */
                        if (STATEP->deltax)
                                VUID_PUTNEXT(qp, (uchar_t)LOC_X_DELTA,
                                    FE_PAIR_ABSOLUTE, (uchar_t)LOC_X_ABSOLUTE,
                                    STATEP->deltax);

                        if (STATEP->deltay)
                                VUID_PUTNEXT(qp, (uchar_t)LOC_Y_DELTA,
                                    FE_PAIR_ABSOLUTE, (uchar_t)LOC_Y_ABSOLUTE,
                                    -STATEP->deltay);

                        STATEP->deltax = STATEP->deltay = 0;
                        break;
                }
        }

        freemsg(mp);
}