/*      $NetBSD: synaptics.c,v 1.85 2026/04/28 17:00:22 christos Exp $  */

/*
 * Copyright (c) 2005, Steve C. Woodford
 * Copyright (c) 2004, Ales Krenek
 * Copyright (c) 2004, Kentaro A. Kurahone
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *   * 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.
 *   * Neither the name of the authors nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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
 * COPYRIGHT OWNER 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.
 *
 */

/*
 * TODO:
 *      - Make the sysctl values per-instance instead of global.
 *      - Consider setting initial scaling factors at runtime according
 *        to the values returned by the 'Read Resolutions' command.
 *      - Support the serial protocol (we only support PS/2 for now)
 *      - Support auto-repeat for up/down button Z-axis emulation.
 *      - Maybe add some more gestures (can we use Palm support somehow?)
 */

#include "opt_pms.h"

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: synaptics.c,v 1.85 2026/04/28 17:00:22 christos Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/ioctl.h>
#include <sys/sysctl.h>
#include <sys/kernel.h>
#include <sys/proc.h>

#include <sys/bus.h>

#include <dev/pckbport/pckbportvar.h>

#include <dev/pckbport/synapticsreg.h>
#include <dev/pckbport/synapticsvar.h>

#include <dev/pckbport/pmsreg.h>
#include <dev/pckbport/pmsvar.h>

#include <dev/wscons/wsconsio.h>
#include <dev/wscons/wsmousevar.h>

/*
 * Absolute-mode packets are decoded and passed around using
 * the following structure.
 */
struct synaptics_packet {
        signed short    sp_x;   /* Unscaled absolute X/Y coordinates */
        signed short    sp_y;
        u_char  sp_z;           /* Z (pressure) */
        signed short    sp_sx;  /* Unscaled absolute X/Y coordinates */
        signed short    sp_sy;  /* for secondary finger */
        u_char  sp_sz;          /* Z (pressure) */
        u_char  sp_w;           /* W (contact patch width) */
        u_char  sp_primary;     /* seen primary finger packet */
        u_char  sp_secondary;   /* seen secondary finger packet */
        u_char  sp_finger_status; /* seen extended finger packet */
        u_char  sp_finger_count; /* number of fingers seen */
        char    sp_left;        /* Left mouse button status */
        char    sp_right;       /* Right mouse button status */
        char    sp_middle;      /* Middle button status (possibly emulated) */
        char    sp_up;          /* Up button status */
        char    sp_down;        /* Down button status */
};

static void pms_synaptics_input(void *, int);
static void pms_synaptics_process_packet(struct pms_softc *,
                struct synaptics_packet *);
static void pms_sysctl_synaptics(struct sysctllog **);
static int pms_sysctl_synaptics_verify(SYSCTLFN_ARGS);

/* Controlled by sysctl. */
static int synaptics_up_down_emul = 3;
static int synaptics_up_down_motion_delta = 1;
static int synaptics_gesture_move = 200;
static int synaptics_gesture_length = 20;
static int synaptics_edge_left = SYNAPTICS_EDGE_LEFT;
static int synaptics_edge_right = SYNAPTICS_EDGE_RIGHT;
static int synaptics_edge_top = SYNAPTICS_EDGE_TOP;
static int synaptics_edge_bottom = SYNAPTICS_EDGE_BOTTOM;
static int synaptics_edge_motion_delta = 32;
static u_int synaptics_finger_high = SYNAPTICS_FINGER_LIGHT + 5;
static u_int synaptics_finger_low = SYNAPTICS_FINGER_LIGHT - 10;
static int synaptics_hscroll_pct = 0;
static int synaptics_vscroll_pct = 0;
static int synaptics_button_pct = 0;
static int synaptics_button_boundary = SYNAPTICS_EDGE_BOTTOM;
static int synaptics_button2;
static int synaptics_button3;
static int synaptics_tap_to_click = 1;
static int synaptics_two_fingers_emul = 0;
static int synaptics_scale_x = 8;
static int synaptics_scale_y = 8;
static int synaptics_scale_z = 32;
static int synaptics_max_speed_x = 32;
static int synaptics_max_speed_y = 32;
static int synaptics_max_speed_z = 2;
static int synaptics_movement_threshold = 4;
static int synaptics_movement_enable = 1;
static int synaptics_button_region_movement = 1;
static bool synaptics_aux_mid_button_scroll = TRUE;
static int synaptics_debug = 0;

#define DPRINTF(LEVEL, SC, FMT, ARGS...) do                                           \
{                                                                             \
        if (synaptics_debug >= LEVEL) {                                               \
                struct pms_softc *_dprintf_psc =                              \
                    container_of((SC), struct pms_softc, u.synaptics);        \
                device_printf(_dprintf_psc->sc_dev, FMT, ##ARGS);             \
        }                                                                     \
} while (0)

/* Sysctl nodes. */
static int synaptics_button_boundary_nodenum;
static int synaptics_button2_nodenum;
static int synaptics_button3_nodenum;
static int synaptics_up_down_emul_nodenum;
static int synaptics_up_down_motion_delta_nodenum;
static int synaptics_gesture_move_nodenum;
static int synaptics_gesture_length_nodenum;
static int synaptics_edge_left_nodenum;
static int synaptics_edge_right_nodenum;
static int synaptics_edge_top_nodenum;
static int synaptics_edge_bottom_nodenum;
static int synaptics_edge_motion_delta_nodenum;
static int synaptics_finger_high_nodenum;
static int synaptics_finger_low_nodenum;
static int synaptics_tap_to_click_nodenum;
static int synaptics_two_fingers_emul_nodenum;
static int synaptics_scale_x_nodenum;
static int synaptics_scale_y_nodenum;
static int synaptics_scale_z_nodenum;
static int synaptics_max_speed_x_nodenum;
static int synaptics_max_speed_y_nodenum;
static int synaptics_max_speed_z_nodenum;
static int synaptics_movement_threshold_nodenum;
static int synaptics_movement_enable_nodenum;
static int synaptics_button_region_movement_nodenum;
static int synaptics_aux_mid_button_scroll_nodenum;
static int synaptics_hscroll_pct_nodenum;
static int synaptics_vscroll_pct_nodenum;
static int synaptics_button_pct_nodenum;

/*
 * copy of edges so we can recalculate edge limit if there is 
 * vertical scroll region
 */
static int synaptics_true_edge_right;
static int synaptics_true_edge_bottom;

/*
 * invalid old values, recalculate everything
 */
static int synaptics_old_vscroll_pct = -1;
static int synaptics_old_hscroll_pct = -1;
static int synaptics_old_button_pct = -1;
static int synaptics_old_button_boundary = -1;
static int synaptics_old_edge_right = -1;
static int synaptics_old_edge_bottom = -1;

/*
 * This holds the processed packet data, it is global because multiple
 * packets from the trackpad may be processed when handling multiple
 * fingers on the trackpad to gather all the data.
 */
static struct synaptics_packet packet;

static int
synaptics_poll_cmd(struct pms_softc *psc, ...)
{
        u_char cmd[4];
        size_t i;
        va_list ap;

        va_start(ap, psc);

        for (i = 0; i < __arraycount(cmd); i++)
                if ((cmd[i] = (u_char)va_arg(ap, int)) == 0)
                        break;
        va_end(ap);

        int res = pckbport_poll_cmd(psc->sc_kbctag, psc->sc_kbcslot, cmd, i, 0,
            NULL, 0);
        if (res)
                device_printf(psc->sc_dev, "command error %#x\n", cmd[0]);
        return res;
}

static int
synaptics_poll_reset(struct pms_softc *psc)
{
        u_char resp[2];
        int res;

        u_char cmd[1] = { PMS_RESET };
        res = pckbport_poll_cmd(psc->sc_kbctag, psc->sc_kbcslot, cmd, 1, 2,
            resp, 1);
        DPRINTF(10, &psc->u.synaptics, "reset %d 0x%02x 0x%02x\n",
            res, resp[0], resp[1]);
        return res;
}

static int
synaptics_special_read(struct pms_softc *psc, u_char slice, u_char resp[3])
{
        u_char cmd[1] = { PMS_SEND_DEV_STATUS };
        int res = pms_sliced_command(psc->sc_kbctag, psc->sc_kbcslot, slice);

        return res | pckbport_poll_cmd(psc->sc_kbctag, psc->sc_kbcslot,
            cmd, 1, 3, resp, 0);
}

static int
synaptics_special_write(struct pms_softc *psc, u_char command, u_char arg)
{
        int res = pms_sliced_command(psc->sc_kbctag, psc->sc_kbcslot, arg);
        if (res)
                return res;

        u_char cmd[2];
        cmd[0] = PMS_SET_SAMPLE;
        cmd[1] = command;
        res = pckbport_poll_cmd(psc->sc_kbctag, psc->sc_kbcslot,
            cmd, 2, 0, NULL, 0);
        return res;
}

static int
synaptics_value(int pct, int low, int high)
{
        return low + pct * (high - low) / 100UL;
}

static int
synaptics_percentage(int val, int low, int high)
{
        return ((val - low) * 100UL + high - low - 1) / (high - low);
}

static void
pms_synaptics_set_boundaries(void)
{
        if (synaptics_vscroll_pct != synaptics_old_vscroll_pct ) {
                synaptics_edge_right = synaptics_value(
                    100 - synaptics_vscroll_pct,
                    synaptics_edge_left,
                    synaptics_true_edge_right);
                synaptics_old_vscroll_pct = synaptics_vscroll_pct;
        }

        if (synaptics_edge_right != synaptics_old_edge_right) {
                if (synaptics_edge_right >= synaptics_true_edge_right) {
                        synaptics_vscroll_pct = 0;
                        synaptics_edge_right = synaptics_true_edge_right;
                } else {
                        synaptics_vscroll_pct = 100 - synaptics_percentage(
                            synaptics_edge_right,
                            synaptics_edge_left,
                            synaptics_true_edge_right);
                }
                synaptics_old_vscroll_pct = synaptics_vscroll_pct;
                synaptics_old_edge_right = synaptics_edge_right;
        }

        if (synaptics_hscroll_pct != synaptics_old_hscroll_pct ) {
                synaptics_edge_bottom = synaptics_value(
                    synaptics_hscroll_pct,
                    synaptics_true_edge_bottom,
                    synaptics_edge_top);
                synaptics_old_hscroll_pct = synaptics_hscroll_pct;
        }

        if (synaptics_edge_bottom != synaptics_old_edge_bottom) {
                if (synaptics_edge_bottom <= synaptics_true_edge_bottom) {
                        synaptics_hscroll_pct = 0;
                        synaptics_edge_bottom = synaptics_true_edge_bottom;
                } else {
                        synaptics_hscroll_pct = synaptics_percentage(
                            synaptics_edge_bottom,
                            synaptics_true_edge_bottom,
                            synaptics_edge_top);
                }
                synaptics_old_hscroll_pct = synaptics_hscroll_pct;
                synaptics_old_edge_bottom = synaptics_edge_bottom;
        }

        if (synaptics_button_pct != synaptics_old_button_pct) {
                synaptics_button_boundary = synaptics_value(
                    synaptics_button_pct,
                    synaptics_edge_bottom,
                    synaptics_edge_top);
                synaptics_old_button_pct = synaptics_button_pct;
        }

        if (synaptics_button_boundary != synaptics_old_button_boundary) {
                if (synaptics_button_boundary <= synaptics_edge_bottom) {
                        synaptics_button_pct = 0;
                        synaptics_button_boundary = synaptics_edge_bottom;
                } else if (synaptics_button_boundary >= synaptics_edge_top) {
                        synaptics_button_pct = 100;
                        synaptics_button_boundary = synaptics_edge_top;
                } else {
                        synaptics_button_pct = synaptics_percentage(
                            synaptics_button_boundary,
                            synaptics_edge_bottom,
                            synaptics_edge_top);
                }
                synaptics_old_button_pct = synaptics_button_pct;
                synaptics_old_button_boundary = synaptics_button_boundary;
        }

        synaptics_button2 = synaptics_edge_left +
            (synaptics_edge_right - synaptics_edge_left) / 3;
        synaptics_button3 = synaptics_edge_left +
            2 * (synaptics_edge_right - synaptics_edge_left) / 3;

}

static void
pms_synaptics_probe_extended(struct pms_softc *psc)
{
        struct synaptics_softc *sc = &psc->u.synaptics;
        u_char resp[3];
        int res;

        DPRINTF(10, sc,
            "synaptics_probe: Capabilities 0x%04x.\n", sc->caps);
        if (sc->caps & SYNAPTICS_CAP_PASSTHROUGH)
                sc->flags |= SYN_FLAG_HAS_PASSTHROUGH;

        if (sc->caps & SYNAPTICS_CAP_PALMDETECT)
                sc->flags |= SYN_FLAG_HAS_PALM_DETECT;

        if (sc->caps & SYNAPTICS_CAP_MULTIDETECT)
                sc->flags |= SYN_FLAG_HAS_MULTI_FINGER;

        if (sc->caps & SYNAPTICS_CAP_MULTIFINGERREPORT)
                sc->flags |= SYN_FLAG_HAS_MULTI_FINGER_REPORT;

        /* Ask about extra buttons to detect up/down. */
        if ((__SHIFTOUT(sc->caps, SYNAPTICS_CAP_EXTNUM) + 0x08)
            >= SYNAPTICS_EXTENDED_QUERY)
        {
                res = synaptics_special_read(psc, SYNAPTICS_EXTENDED_QUERY, resp);
                if (res == 0) {
                        sc->num_buttons = (resp[1] >> 4);
                        if (sc->num_buttons > 0)
                                sc->button_mask = sc->button_mask <<
                                    ((sc->num_buttons + 1) >> 1);

                        DPRINTF(10, sc,
                            "Extended Buttons: %d.\n",
                            sc->num_buttons);

                        DPRINTF(10, sc, "Extended "
                            "Capabilities: 0x%02x 0x%02x 0x%02x.\n",
                            resp[0], resp[1], resp[2]);
                        if (sc->num_buttons >= 2) {
                                /* Yes. */
                                sc->flags |= SYN_FLAG_HAS_UP_DOWN_BUTTONS;
                        }
                        if (resp[0] & 0x1) {
                                /* Vertical scroll area */
                                sc->flags |= SYN_FLAG_HAS_VERTICAL_SCROLL;
                        }
                        if (resp[0] & 0x2) {
                                /* Horizontal scroll area */
                                sc->flags |= SYN_FLAG_HAS_HORIZONTAL_SCROLL;
                        }
                        if (resp[0] & 0x4) {
                                /* Extended W-Mode */
                                sc->flags |= SYN_FLAG_HAS_EXTENDED_WMODE;
                        }
                }
        }

        /* Ask about click pad */
        if ((__SHIFTOUT(sc->caps, SYNAPTICS_CAP_EXTNUM) + 0x08) >=
            SYNAPTICS_CONTINUED_CAPABILITIES)
        {
                res = synaptics_special_read(psc,
                    SYNAPTICS_CONTINUED_CAPABILITIES, resp);

/*
 * The following describes response for the
 * SYNAPTICS_CONTINUED_CAPABILITIES query.
 *
 * byte mask    name                    meaning
 * ---- ----    -------                 ------------
 * 0    0x01    adjustable threshold    capacitive button sensitivity
 *                                      can be adjusted
 * 0    0x02    report max              query 0x0d gives max coord reported
 * 0    0x04    clearpad                sensor is ClearPad product
 * 0    0x08    advanced gesture        not particularly meaningful
 * 0    0x10    clickpad bit 0          1-button ClickPad
 * 0    0x60    multifinger mode        identifies firmware finger counting
 *                                      (not reporting!) algorithm.
 *                                      Not particularly meaningful
 * 0    0x80    covered pad             W clipped to 14, 15 == pad mostly covered
 * 1    0x01    clickpad bit 1          2-button ClickPad
 * 1    0x02    deluxe LED controls     touchpad support LED commands
 *                                      ala multimedia control bar
 * 1    0x04    reduced filtering       firmware does less filtering on
 *                                      position data, driver should watch
 *                                      for noise.
 * 1    0x08    image sensor            image sensor tracks 5 fingers, but only
 *                                      reports 2.
 * 1    0x10    uniform clickpad        whole clickpad moves instead of being
 *                                      hinged at the top.
 * 1    0x20    report min              query 0x0f gives min coord reported
 */
                if (res == 0) {
                        uint val = SYN_CCAP_VALUE(resp);

                        DPRINTF(10, sc, "Continued "
                            "Capabilities 0x%02x 0x%02x 0x%02x.\n",
                            resp[0], resp[1], resp[2]);
                        switch (SYN_CCAP_CLICKPAD_TYPE(val)) {
                        case 0: /* not a clickpad */
                                break;
                        case 1:
                                sc->flags |= SYN_FLAG_HAS_ONE_BUTTON_CLICKPAD;
                                break;
                        case 2:
                                sc->flags |= SYN_FLAG_HAS_TWO_BUTTON_CLICKPAD;
                                break;
                        case 3: /* reserved */
                        default:
                                /* unreached */
                                break;
                        }

                        if ((val & SYN_CCAP_HAS_ADV_GESTURE_MODE))
                                sc->flags |= SYN_FLAG_HAS_ADV_GESTURE_MODE;

                        if ((val & SYN_CCAP_REPORT_MAX))
                                sc->flags |= SYN_FLAG_HAS_MAX_REPORT;

                        if ((val & SYN_CCAP_REPORT_MIN))
                                sc->flags |= SYN_FLAG_HAS_MIN_REPORT;
                }
        }
}

static const struct {
        int bit;
        const char *desc;
} syn_flags[] = {
        { SYN_FLAG_HAS_EXTENDED_WMODE, "Extended W mode", },
        { SYN_FLAG_HAS_PASSTHROUGH, "Passthrough", },
        { SYN_FLAG_HAS_MIDDLE_BUTTON, "Middle button", },
        { SYN_FLAG_HAS_BUTTONS_4_5, "Buttons 4/5", },
        { SYN_FLAG_HAS_UP_DOWN_BUTTONS, "Up/down buttons", },
        { SYN_FLAG_HAS_PALM_DETECT, "Palm detect", },
        { SYN_FLAG_HAS_ONE_BUTTON_CLICKPAD, "One button click pad", },
        { SYN_FLAG_HAS_TWO_BUTTON_CLICKPAD, "Two button click pad", },
        { SYN_FLAG_HAS_VERTICAL_SCROLL, "Vertical scroll", },
        { SYN_FLAG_HAS_HORIZONTAL_SCROLL, "Horizontal scroll", },
        { SYN_FLAG_HAS_MULTI_FINGER_REPORT, "Multi-finger Report", },
        { SYN_FLAG_HAS_MULTI_FINGER, "Multi-finger", },
        { SYN_FLAG_HAS_MAX_REPORT, "Reports max", },
        { SYN_FLAG_HAS_MIN_REPORT, "Reports min", },
};

int
pms_synaptics_probe_init(void *vsc)
{
        struct pms_softc *psc = vsc;
        struct synaptics_softc *sc = &psc->u.synaptics;
        u_char cmd[1], resp[3];
        int res, ver_minor, ver_major;
        struct sysctllog *clog = NULL;

        res = pms_sliced_command(psc->sc_kbctag, psc->sc_kbcslot,
            SYNAPTICS_IDENTIFY_TOUCHPAD);
        cmd[0] = PMS_SEND_DEV_STATUS;
        res |= pckbport_poll_cmd(psc->sc_kbctag, psc->sc_kbcslot, cmd, 1, 3,
            resp, 0);
        if (res) {
                aprint_debug_dev(psc->sc_dev,
                    "synaptics_probe: Identify Touchpad error.\n");
                /*
                 * Reset device in case the probe confused it.
                 */
 doreset:
                (void)synaptics_poll_reset(psc);
                return res;
        }

        if (resp[1] != SYNAPTICS_MAGIC_BYTE) {
                aprint_debug_dev(psc->sc_dev,
                    "synaptics_probe: Not synaptics.\n");
                res = 1;
                goto doreset;
        }

        sc->flags = 0;
        sc->num_buttons = 0;
        sc->button_mask = 0xff;

        synaptics_true_edge_right = synaptics_edge_right;
        synaptics_true_edge_bottom = synaptics_edge_bottom;

        /* Check for minimum version and print a nice message. */
        ver_major = resp[2] & 0x0f;
        ver_minor = resp[0];
        aprint_normal_dev(psc->sc_dev, "Synaptics touchpad version %d.%d\n",
            ver_major, ver_minor);
        if (ver_major * 10 + ver_minor < SYNAPTICS_MIN_VERSION) {
                /* No capability query support. */
                sc->caps = 0;
                goto done;
        }

        /* Query the hardware capabilities. */
        res = synaptics_special_read(psc, SYNAPTICS_READ_CAPABILITIES, resp);
        if (res) {
                /* Hmm, failed to get capabilities. */
                aprint_error_dev(psc->sc_dev,
                    "synaptics_probe: Failed to query capabilities.\n");
                goto doreset;
        }

        sc->caps = SYNAPTICS_CAP_VALUE(resp);

        if (sc->caps & SYNAPTICS_CAP_MBUTTON)
                sc->flags |= SYN_FLAG_HAS_MIDDLE_BUTTON;

        if (sc->caps & SYNAPTICS_CAP_4BUTTON)
                sc->flags |= SYN_FLAG_HAS_BUTTONS_4_5;

        if (sc->caps & SYNAPTICS_CAP_EXTENDED) {
                pms_synaptics_probe_extended(psc);
        }

        if (sc->flags) {
                const char comma[] = ", ";
                const char *sep = "";
                aprint_normal_dev(psc->sc_dev, "");
                for (size_t f = 0; f < __arraycount(syn_flags); f++) {
                        if (sc->flags & syn_flags[f].bit) {
                                aprint_normal("%s%s", sep, syn_flags[f].desc);
                                sep = comma;
                        }
                }
                aprint_normal("\n");
        }

        if (sc->flags & SYN_FLAG_HAS_MAX_REPORT) {
                res = synaptics_special_read(psc, SYNAPTICS_READ_MAX_COORDS,
                    resp);
                if (res) {
                        aprint_error_dev(psc->sc_dev,
                            "synaptics_probe: Failed to query max coords.\n");
                } else {
                        synaptics_edge_right = (resp[0] << 5) +
                            ((resp[1] & 0x0f) << 1);
                        synaptics_edge_top = (resp[2] << 5) + 
                            ((resp[1] & 0xf0) >> 3);

                        synaptics_true_edge_right = synaptics_edge_right;

                        /*
                         * If we have vertical scroll then steal 10%
                         * for that region.
                         */
                        if (sc->flags & SYN_FLAG_HAS_VERTICAL_SCROLL)
                                synaptics_edge_right -=
                                    synaptics_edge_right / 10;

                        aprint_normal_dev(psc->sc_dev,
                            "Probed max coordinates right: %d, top: %d\n",
                            synaptics_edge_right, synaptics_edge_top);
                }
        }

        if (sc->flags & SYN_FLAG_HAS_MIN_REPORT) {
                res = synaptics_special_read(psc, SYNAPTICS_READ_MIN_COORDS,
                    resp);
                if (res) {
                        aprint_error_dev(psc->sc_dev,
                            "synaptics_probe: Failed to query min coords.\n");
                } else {
                        synaptics_edge_left = (resp[0] << 5) +
                            ((resp[1] & 0x0f) << 1);
                        synaptics_edge_bottom = (resp[2] << 5) + 
                            ((resp[1] & 0xf0) >> 3);

                        synaptics_true_edge_bottom = synaptics_edge_bottom;

                        /*
                         * If we have horizontal scroll then steal 10%
                         * for that region.
                         */
                        if (sc->flags & SYN_FLAG_HAS_HORIZONTAL_SCROLL)
                                synaptics_hscroll_pct = 10;

                        aprint_normal_dev(psc->sc_dev,
                            "Probed min coordinates left: %d, bottom: %d\n",
                            synaptics_edge_left, synaptics_edge_bottom);
                }
        }

done:
        pms_synaptics_set_boundaries();

        pms_sysctl_synaptics(&clog);
        pckbport_set_inputhandler(psc->sc_kbctag, psc->sc_kbcslot,
            pms_synaptics_input, psc, device_xname(psc->sc_dev));

        return (0);
}

void
pms_synaptics_enable(void *vsc)
{
        struct pms_softc *psc = vsc;
        struct synaptics_softc *sc = &psc->u.synaptics;
        u_char enable_modes;
        int res, i;

        if (sc->flags & SYN_FLAG_HAS_PASSTHROUGH) {
                /*
                 * Extended capability probes can confuse the passthrough
                 * device; reset the touchpad now to cure that.
                 */
                res = synaptics_poll_reset(psc);
        }

        /*
         * Enable Absolute mode with W (width) reporting, and set
         * the packet rate to maximum (80 packets per second). Enable
         * extended W mode if supported so we can report second finger
         * position.
         */
        enable_modes =
           SYNAPTICS_MODE_ABSOLUTE | SYNAPTICS_MODE_W | SYNAPTICS_MODE_RATE;

        if (sc->flags & SYN_FLAG_HAS_EXTENDED_WMODE)
                enable_modes |= SYNAPTICS_MODE_EXTENDED_W;

        /*
        * Synaptics documentation says to disable device before
        * setting mode.
        */
        synaptics_poll_cmd(psc, PMS_DEV_DISABLE, 0);
        /* a couple of set scales to clear out pending commands */
        for (i = 0; i < 2; i++)
                synaptics_poll_cmd(psc, PMS_SET_SCALE11, 0);

        res = synaptics_special_write(psc, SYNAPTICS_CMD_SET_MODE2, enable_modes);
        if (res)
                device_printf(psc->sc_dev, "set mode error\n");

        /* a couple of set scales to clear out pending commands */
        for (i = 0; i < 2; i++)
                synaptics_poll_cmd(psc, PMS_SET_SCALE11, 0);

        /* Set advanced gesture mode */
        if ((sc->flags & SYN_FLAG_HAS_EXTENDED_WMODE) ||
            (sc->flags & SYN_FLAG_HAS_ADV_GESTURE_MODE))
                synaptics_special_write(psc, SYNAPTICS_WRITE_DELUXE_3, 0x3); 

        /* Disable motion in the button region for clickpads */
        if(sc->flags & SYN_FLAG_HAS_ONE_BUTTON_CLICKPAD)
                synaptics_button_region_movement = 0;

        sc->up_down = 0;
        sc->prev_fingers = 0;
        sc->gesture_start_x = sc->gesture_start_y = 0;
        sc->gesture_start_packet = 0;
        sc->gesture_tap_packet = 0;
        sc->gesture_type = 0;
        sc->gesture_buttons = 0;
        sc->total_packets = 0;
        for (i = 0; i < SYN_MAX_FINGERS; i++) {
                sc->rem_x[i] = sc->rem_y[i] = sc->rem_z[i] = 0;
        }
        sc->button_history = 0;

        /* clear the packet decode structure */
        memset(&packet, 0, sizeof(packet));
}

void
pms_synaptics_resume(void *vsc)
{
        (void)synaptics_poll_reset(vsc);
}

static void
pms_sysctl_synaptics(struct sysctllog **clog)
{
        int rc, root_num;
        const struct sysctlnode *node;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT, CTLTYPE_NODE, "synaptics",
            SYSCTL_DESCR("Synaptics touchpad controls"),
            NULL, 0, NULL, 0, CTL_HW, CTL_CREATE, CTL_EOL)) != 0)
            goto err;

        root_num = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "up_down_emulation",
            SYSCTL_DESCR("Middle button/Z-axis emulation with up/down buttons"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_up_down_emul,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_up_down_emul_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "up_down_motion_delta",
            SYSCTL_DESCR("Up/down button Z-axis emulation rate"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_up_down_motion_delta,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_up_down_motion_delta_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "gesture_move",
            SYSCTL_DESCR("Movement greater than this between taps cancels gesture"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_gesture_move,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_gesture_move_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "gesture_length",
            SYSCTL_DESCR("Time period in which tap is recognised as a gesture"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_gesture_length,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_gesture_length_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "edge_left",
            SYSCTL_DESCR("Define left edge of touchpad"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_edge_left,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_edge_left_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "edge_right",
            SYSCTL_DESCR("Define right edge of touchpad"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_edge_right,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_edge_right_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "edge_top",
            SYSCTL_DESCR("Define top edge of touchpad"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_edge_top,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_edge_top_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "edge_bottom",
            SYSCTL_DESCR("Define bottom edge of touchpad"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_edge_bottom,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_edge_bottom_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "edge_motion_delta",
            SYSCTL_DESCR("Define edge motion rate"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_edge_motion_delta,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_edge_motion_delta_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "finger_high",
            SYSCTL_DESCR("Define finger applied pressure threshold"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_finger_high,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_finger_high_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "finger_low",
            SYSCTL_DESCR("Define finger removed pressure threshold"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_finger_low,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_finger_low_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "tap_to_click",
            SYSCTL_DESCR("Enable tap to click"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_tap_to_click,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_tap_to_click_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "two_fingers_emulation",
            SYSCTL_DESCR("Map two fingers to middle button"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_two_fingers_emul,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_two_fingers_emul_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "scale_x",
            SYSCTL_DESCR("Horizontal movement scale factor"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_scale_x,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_scale_x_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "scale_y",
            SYSCTL_DESCR("Vertical movement scale factor"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_scale_y,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_scale_y_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "scale_z",
            SYSCTL_DESCR("Sroll wheel emulation scale factor"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_scale_z,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_scale_z_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "max_speed_x",
            SYSCTL_DESCR("Horizontal movement maximum speed"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_max_speed_x,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_max_speed_x_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "max_speed_y",
            SYSCTL_DESCR("Vertical movement maximum speed"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_max_speed_y,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_max_speed_y_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "max_speed_z",
            SYSCTL_DESCR("Scroll wheel emulation maximum speed"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_max_speed_z,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_max_speed_z_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "movement_threshold",
            SYSCTL_DESCR("Minimum reported movement threshold"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_movement_threshold,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_movement_threshold_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "movement_enable",
            SYSCTL_DESCR("Enable movement reporting"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_movement_enable,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_movement_enable_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "button_region_movement_enable",
            SYSCTL_DESCR("Enable movement within clickpad button region"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_button_region_movement,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_button_region_movement_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "button_boundary",
            SYSCTL_DESCR("Top edge of button area"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_button_boundary,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_button_boundary_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "button2_edge",
            SYSCTL_DESCR("Left edge of button 2 region"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_button2,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_button2_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "button3_edge",
            SYSCTL_DESCR("Left edge of button 3 region"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_button3,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_button3_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_BOOL, "aux_mid_button_scroll",
            SYSCTL_DESCR("Interpret Y-Axis movement with the middle button held as scrolling on the passthrough device (e.g. TrackPoint)"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_aux_mid_button_scroll,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_aux_mid_button_scroll_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "vert_scroll_percent",
            SYSCTL_DESCR("Percent of trackpad width to reserve for vertical scroll region"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_vscroll_pct,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_vscroll_pct_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "horizontal_scroll_percent",
            SYSCTL_DESCR("Percent of trackpad height to reserve for scroll region"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_hscroll_pct,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_hscroll_pct_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "button_region_percent",
            SYSCTL_DESCR("Percent of trackpad height to reserve for button region"),
            pms_sysctl_synaptics_verify, 0,
            &synaptics_button_pct,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        synaptics_button_pct_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "debug",
            SYSCTL_DESCR("Enable debug output"),
            NULL, 0,
            &synaptics_debug,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        return;

err:
        aprint_error("%s: sysctl_createv failed (rc = %d)\n", __func__, rc);
}

static int
pms_sysctl_synaptics_verify(SYSCTLFN_ARGS)
{
        int error, t;
        struct sysctlnode node;

        node = *rnode;
        t = *(int *)rnode->sysctl_data;
        node.sysctl_data = &t;
        error = sysctl_lookup(SYSCTLFN_CALL(&node));
        if (error || newp == NULL)
                return error;

        /* Sanity check the params. */
        if (node.sysctl_num == synaptics_up_down_emul_nodenum) {
                if (t < 0 || t > 3)
                        return (EINVAL);
        } else
        if (node.sysctl_num == synaptics_tap_to_click_nodenum) {
                if (t < 0 || t > 1)
                        return (EINVAL);
        } else
        if (node.sysctl_num == synaptics_two_fingers_emul_nodenum) {
                if (t < 0 || t > 2)
                        return (EINVAL);
        } else
        if (node.sysctl_num == synaptics_gesture_length_nodenum ||
            node.sysctl_num == synaptics_edge_motion_delta_nodenum ||
            node.sysctl_num == synaptics_up_down_motion_delta_nodenum ||
            node.sysctl_num == synaptics_max_speed_x_nodenum ||
            node.sysctl_num == synaptics_max_speed_y_nodenum ||
            node.sysctl_num == synaptics_max_speed_z_nodenum) {
                if (t < 0)
                        return (EINVAL);
        } else
        if (node.sysctl_num == synaptics_edge_left_nodenum ||
            node.sysctl_num == synaptics_edge_bottom_nodenum) {
                if (t < 0 || t > (SYNAPTICS_EDGE_MAX / 2))
                        return (EINVAL);
        } else
        if (node.sysctl_num == synaptics_edge_right_nodenum ||
            node.sysctl_num == synaptics_edge_top_nodenum) {
                if (t < (SYNAPTICS_EDGE_MAX / 2))
                        return (EINVAL);
        } else
        if (node.sysctl_num == synaptics_scale_x_nodenum ||
            node.sysctl_num == synaptics_scale_y_nodenum ||
            node.sysctl_num == synaptics_scale_z_nodenum) {
                if (t < 1 || t > (SYNAPTICS_EDGE_MAX / 4))
                        return (EINVAL);
        } else
        if (node.sysctl_num == synaptics_finger_high_nodenum) {
                if (t < 0 || t > SYNAPTICS_FINGER_PALM ||
                    t < synaptics_finger_low)
                        return (EINVAL);
        } else
        if (node.sysctl_num == synaptics_finger_low_nodenum) {
                if (t < 0 || t > SYNAPTICS_FINGER_PALM ||
                    t > synaptics_finger_high)
                        return (EINVAL);
        } else
        if (node.sysctl_num == synaptics_gesture_move_nodenum ||
            node.sysctl_num == synaptics_movement_threshold_nodenum) {
                if (t < 0 || t > (SYNAPTICS_EDGE_MAX / 4))
                        return (EINVAL);
        } else
        if (node.sysctl_num == synaptics_button_boundary_nodenum) {
                if (t < 0 || t < synaptics_edge_bottom ||
                    t > synaptics_edge_top)
                        return (EINVAL);
        } else
        if (node.sysctl_num == synaptics_button2_nodenum ||
            node.sysctl_num == synaptics_button3_nodenum) {
                if (t < synaptics_edge_left || t > synaptics_edge_right)
                        return (EINVAL);
        } else
        if (node.sysctl_num == synaptics_movement_enable_nodenum) {
                if (t < 0 || t > 1)
                        return (EINVAL);
        } else
        if (node.sysctl_num == synaptics_button_region_movement_nodenum) {
                if (t < 0 || t > 1)
                        return (EINVAL);
        } else
        if (node.sysctl_num == synaptics_aux_mid_button_scroll_nodenum) {
                if (t < 0 || t > 1)
                        return (EINVAL);
        } else
        if (node.sysctl_num == synaptics_vscroll_pct_nodenum) {
                if (t < 0 || t > 100)
                        return (EINVAL);
        } else
        if (node.sysctl_num == synaptics_hscroll_pct_nodenum) {
                if (t < 0 || t > 100)
                        return (EINVAL);
        } else
        if (node.sysctl_num == synaptics_button_pct_nodenum) {
                if (t < 0 || t > 100)
                        return (EINVAL);
        } else
                return (EINVAL);

        *(int *)rnode->sysctl_data = t;

        pms_synaptics_set_boundaries();

        return (0);
}

/*
 * Extract the number of fingers from the current packet and return
 * it to the caller.
 */
static unsigned
pms_synaptics_get_fingers(struct pms_softc *psc, u_char w, short z)
{
        struct synaptics_softc *sc = &psc->u.synaptics;
        unsigned short ew_mode;
        unsigned fingers;

        fingers = 0;


        /*
         * If w is zero and z says no fingers then return
         * no fingers, w == can also mean 2 fingers... confusing.
         */
        if (w == 0 && z == SYNAPTICS_FINGER_NONE)
                return 0;

        if ((sc->flags & SYN_FLAG_HAS_EXTENDED_WMODE) &&
            (w == SYNAPTICS_WIDTH_EXTENDED_W)) {
                ew_mode = psc->packet[5] >> 4;
                switch (ew_mode)
                {
                case SYNAPTICS_EW_WHEEL:
                        break;

                case SYNAPTICS_EW_SECONDARY_FINGER:
                        /* to get here we must have 2 fingers at least */
                        fingers = 2;
                        break;

                case SYNAPTICS_EW_FINGER_STATUS:
                        fingers = psc->packet[1] & 0x0f;
                        break;

                default:
                        device_printf(psc->sc_dev,
                            "invalid extended w mode %d\n",
                            ew_mode);
                        return 0; /* pretend there are no fingers */
                }
        } else {

                fingers = 1;

                /*
                 * If SYN_FLAG_HAS_MULTI_FINGER is set then check
                 * sp_w is below SYNAPTICS_WIDTH_FINGER_MIN, if it is
                 * then this will be the finger count.
                 *
                 * There are a couple of "special" values otherwise
                 * just punt with one finger, if this really is a palm
                 * then it will be caught later.
                 */
                if (sc->flags & (SYN_FLAG_HAS_MULTI_FINGER | SYN_FLAG_HAS_MULTI_FINGER_REPORT)) {
                        if (w == SYNAPTICS_WIDTH_TWO_FINGERS)
                                fingers = 2;
                        else if (w == SYNAPTICS_WIDTH_THREE_OR_MORE)
                                fingers = 3;
                }

        }

        return fingers;
}

/* Masks for the first byte of a packet */
#define PMS_LBUTMASK 0x01
#define PMS_RBUTMASK 0x02
#define PMS_MBUTMASK 0x04

static void
pms_synaptics_parse(struct pms_softc *psc)
{
        struct synaptics_softc *sc = &psc->u.synaptics;
        struct synaptics_packet nsp;
        char new_buttons, ew_mode;
        uint8_t btn_mask, packet4, packet5;
        unsigned v, primary_finger, secondary_finger;
        int ext_left = -1, ext_right = -1, ext_middle = -1,
            ext_up = -1, ext_down = -1;

        sc->total_packets++;

        memcpy(&nsp, &packet, sizeof(packet));

        /* Width of finger */
        nsp.sp_w = ((psc->packet[0] & 0x30) >> 2)
            + ((psc->packet[0] & 0x04) >> 1)
            + ((psc->packet[3] & 0x04) >> 2);

        v = 0;
        primary_finger = 0;
        secondary_finger = 0;
        if ((sc->flags & SYN_FLAG_HAS_EXTENDED_WMODE) &&
            (nsp.sp_w == SYNAPTICS_WIDTH_EXTENDED_W)) {
                ew_mode = psc->packet[5] >> 4;
                switch (ew_mode)
                {
                case SYNAPTICS_EW_WHEEL:
                        /* scroll wheel report, ignore for now */
                        DPRINTF(10, sc, "mouse wheel packet\n");
                        return;

                case SYNAPTICS_EW_SECONDARY_FINGER:
                        /* parse the second finger report */

                        nsp.sp_secondary = 1;

                        nsp.sp_sx = ((psc->packet[1] & 0xfe) << 1)
                            + ((psc->packet[4] & 0x0f) << 9);
                        nsp.sp_sy = ((psc->packet[2] & 0xfe) << 1)
                            + ((psc->packet[4] & 0xf0) << 5);
                        nsp.sp_sz = (psc->packet[3] & 0x30)
                            + ((psc->packet[5] & 0x0e) << 1);

                        /*
                         * Check if the x and y are non-zero that they
                         * are within the bounds of the trackpad
                         * otherwise ignore the packet.
                         */
                        if (((nsp.sp_sx != 0) &&
                            ((nsp.sp_sx < synaptics_edge_left) ||
                             (nsp.sp_sx > synaptics_edge_right))) ||
                           ((nsp.sp_sy != 0) &&
                            ((nsp.sp_sy < synaptics_edge_bottom) ||
                             (nsp.sp_sy > synaptics_edge_top)))) {
                                sc->gesture_type = 0;
                                sc->gesture_buttons = 0;
                                sc->total_packets--;
                                DPRINTF(20, sc,
                                    "synaptics_parse: dropping out of bounds "
                                    "packet sp_sx %d sp_sy %d\n",
                                    nsp.sp_sx, nsp.sp_sy);
                                return;
                        }

                        /* work out the virtual finger width */
                        v = 8 + (psc->packet[1] & 0x01) +
                                ((psc->packet[2] & 0x01) << 1) +
                                ((psc->packet[5] & 0x01) << 2);

                        /* keep same buttons down as primary */
                        nsp.sp_left = sc->button_history & PMS_LBUTMASK;
                        nsp.sp_middle = sc->button_history & PMS_MBUTMASK;
                        nsp.sp_right = sc->button_history & PMS_RBUTMASK;
                        break;

                case SYNAPTICS_EW_FINGER_STATUS:
                        /* This works but what is it good for?
                         * it gives us an index of the primary/secondary
                         * fingers but no other packets pass this
                         * index.
                         *
                         * XXX Park this, possibly handle a finger
                         * XXX change if indexes change.
                         */
                        primary_finger = psc->packet[2];
                        secondary_finger = psc->packet[4];
                        nsp.sp_finger_status = 1;
                        nsp.sp_finger_count = pms_synaptics_get_fingers(psc,
                            nsp.sp_w, nsp.sp_z);
                        goto skip_position;

                default:
                        device_printf(psc->sc_dev,
                            "invalid extended w mode %d\n",
                            ew_mode);
                        return;
                }
        } else {
                nsp.sp_primary = 1;

                /*
                 * If the trackpad has external buttons and one of
                 * those buttons is pressed then the lower bits of
                 * x and y are "stolen" for button status. We can tell
                 * this has happened by doing an xor of the two right
                 * button status bits residing in byte 0 and 3, if the
                 * result is non-zero then there is an external button
                 * report and the position bytes need to be masked.
                 */
                btn_mask = 0xff;
                if ((sc->num_buttons > 0) &&
                    ((psc->packet[0] & PMS_RBUTMASK) ^
                     (psc->packet[3] & PMS_RBUTMASK))) {
                        btn_mask = sc->button_mask;
                }

                packet4 = psc->packet[4] & btn_mask;
                packet5 = psc->packet[5] & btn_mask;

                /*
                 * If SYN_FLAG_HAS_MULTI_FINGER is set then check
                 * sp_w is below SYNAPTICS_WIDTH_FINGER_MIN, if it is
                 * then this will be the finger count.
                 *
                 * There are a couple of "special" values otherwise
                 * just punt with one finger, if this really is a palm
                 * then it will be caught later.
                 */
                if ((sc->flags & SYN_FLAG_HAS_MULTI_FINGER) &&
                    ((nsp.sp_w == SYNAPTICS_WIDTH_TWO_FINGERS) ||
                     (nsp.sp_w == SYNAPTICS_WIDTH_THREE_OR_MORE))) {
                        /*
                         * To make life interesting if there are
                         * two or more fingers on the touchpad then
                         * the coordinate reporting changes and an extra
                         * "virtual" finger width is reported.
                         */
                        nsp.sp_x = (packet4 & 0xfc) +
                                ((packet4 & 0x02) << 1) +
                                ((psc->packet[1] & 0x0f) << 8) +
                                ((psc->packet[3] & 0x10) << 8);

                        nsp.sp_y = (packet5 & 0xfc) +
                                ((packet5 & 0x02) << 1) +
                                ((psc->packet[1] & 0xf0) << 4) +
                                ((psc->packet[3] & 0x20) << 7);

                        /* Pressure */
                        nsp.sp_z = psc->packet[2] & 0xfe;

                        /* derive the virtual finger width */
                        v = 8 + ((packet4 & 0x02) >> 1) +
                                (packet5 & 0x02) +
                                ((psc->packet[2] & 0x01) << 2);

                } else {
                        /* Absolute X/Y coordinates of finger */
                        nsp.sp_x = packet4 +
                                ((psc->packet[1] & 0x0f) << 8) +
                                ((psc->packet[3] & 0x10) << 8);

                        nsp.sp_y = packet5 +
                                ((psc->packet[1] & 0xf0) << 4) +
                                ((psc->packet[3] & 0x20) << 7);

                        /* Pressure */
                        nsp.sp_z = psc->packet[2];
                }

                /*
                 * Check if the x and y are non-zero that they
                 * are within the bounds of the trackpad
                 * otherwise ignore the packet.
                 */
                if (((nsp.sp_x != 0) &&
                    ((nsp.sp_x < synaptics_edge_left) ||
                     (nsp.sp_x > synaptics_edge_right))) ||
                    ((nsp.sp_y != 0) &&
                    ((nsp.sp_y < synaptics_edge_bottom) ||
                     (nsp.sp_y > synaptics_edge_top)))) {
                        sc->gesture_type = 0;
                        sc->gesture_buttons = 0;
                        sc->total_packets--;
                        DPRINTF(20, sc,
                            "synaptics_parse: dropping out of bounds packet "
                            "sp_x %d sp_y %d\n",
                            nsp.sp_x, nsp.sp_y);
                        return;
                }

                nsp.sp_finger_count = pms_synaptics_get_fingers(psc,
                    nsp.sp_w, nsp.sp_z);

                /*
                 * We don't have extended W so we only know if there
                 * are multiple fingers on the touchpad, only the primary
                 * location is reported so just pretend we have an
                 * unmoving second finger.
                 */
                if (((sc->flags & SYN_FLAG_HAS_EXTENDED_WMODE)
                        != SYN_FLAG_HAS_EXTENDED_WMODE) &&
                    (nsp.sp_finger_count > 1)) {
                        nsp.sp_secondary = 1;
                        nsp.sp_sx = 0;
                        nsp.sp_sy = 0;
                        nsp.sp_sz = 0;
                }

                if ((psc->packet[0] ^ psc->packet[3]) & 0x02) {
                        /* extended buttons */

                        DPRINTF(10, sc,
                            "synaptics_parse: %02x %02x %02x %02x %02x %02x\n",
                            psc->packet[0], psc->packet[1], psc->packet[2],
                            psc->packet[3], psc->packet[4], psc->packet[5]);

                        if ((psc->packet[4] & SYN_1BUTMASK) != 0)
                                ext_left = PMS_LBUTMASK;
                        else
                                ext_left = 0;

                        if ((psc->packet[4] & SYN_3BUTMASK) != 0)
                                ext_middle = PMS_MBUTMASK;
                        else
                                ext_middle = 0;

                        if ((psc->packet[5] & SYN_2BUTMASK) != 0)
                                ext_right = PMS_RBUTMASK;
                        else
                                ext_right = 0;

                        if ((psc->packet[5] & SYN_4BUTMASK) != 0)
                                ext_up = 1;
                        else
                                ext_up = 0;

                        if ((psc->packet[4] & SYN_5BUTMASK) != 0)
                                ext_down = 1;
                        else
                                ext_down = 0;
                } else {
                        /* Left/Right button handling. */
                        nsp.sp_left = psc->packet[0] & PMS_LBUTMASK;
                        nsp.sp_right = psc->packet[0] & PMS_RBUTMASK;
                }

                /* Up/Down buttons. */
                if (sc->flags & SYN_FLAG_HAS_BUTTONS_4_5) {
                        /* Old up/down buttons. */
                        nsp.sp_up = nsp.sp_left ^
                            (psc->packet[3] & PMS_LBUTMASK);
                        nsp.sp_down = nsp.sp_right ^
                            (psc->packet[3] & PMS_RBUTMASK);
                } else if (sc->flags & SYN_FLAG_HAS_UP_DOWN_BUTTONS &&
                    ((psc->packet[0] & PMS_RBUTMASK) ^
                    (psc->packet[3] & PMS_RBUTMASK))) {
                        /* New up/down button. */
                        nsp.sp_up = psc->packet[4] & SYN_1BUTMASK;
                        nsp.sp_down = psc->packet[5] & SYN_2BUTMASK;
                } else {
                        nsp.sp_up = 0;
                        nsp.sp_down = 0;
                }

                new_buttons = 0;
                if(sc->flags & SYN_FLAG_HAS_ONE_BUTTON_CLICKPAD) {
                        /* This is not correctly specified. Read this button press
                        * from L/U bit.  Emulate 3 buttons by checking the
                        * coordinates of the click and returning the appropriate
                        * button code.  Outside the button region default to a
                        * left click.
                        */
                        u_char bstate = (psc->packet[0] ^ psc->packet[3])
                                            & 0x01;
                        if (nsp.sp_y < synaptics_button_boundary) {
                                if (nsp.sp_x > synaptics_button3) {
                                        nsp.sp_right =
                                                bstate ? PMS_RBUTMASK : 0;
                                } else if (nsp.sp_x > synaptics_button2) {
                                        nsp.sp_middle =
                                                bstate ? PMS_MBUTMASK : 0;
                                } else {
                                        nsp.sp_left = bstate ? PMS_LBUTMASK : 0;
                                }
                        } else
                                nsp.sp_left = bstate ? 1 : 0;
                        new_buttons = nsp.sp_left | nsp.sp_middle | nsp.sp_right;
                        if (new_buttons != sc->button_history) {
                                if (sc->button_history == 0)
                                        sc->button_history = new_buttons;
                                else if (new_buttons == 0) {
                                        sc->button_history = 0;
                                       /* ensure all buttons are cleared just in
                                        * case finger comes off in a different
                                        * region.
                                        */
                                        nsp.sp_left = 0;
                                        nsp.sp_middle = 0;
                                        nsp.sp_right = 0;
                                } else {
                                        /* make sure we keep the same button even
                                        * if the finger moves to a different
                                        * region.  This precludes chording
                                        * but, oh well.
                                        */
                                        nsp.sp_left = sc->button_history & PMS_LBUTMASK;
                                        nsp.sp_middle = sc->button_history
                                        & PMS_MBUTMASK;
                                        nsp.sp_right = sc->button_history & PMS_RBUTMASK;
                                }
                        }
                } else if (sc->flags & SYN_FLAG_HAS_MIDDLE_BUTTON) {
                        /* Old style Middle Button. */
                        nsp.sp_middle = (psc->packet[0] & PMS_LBUTMASK) ^
                            (psc->packet[3] & PMS_LBUTMASK);
                } else {
                        nsp.sp_middle = 0;
                }

                /*
                 * Overlay extended button state if anything changed,
                 * preserve the state if a button is being held.
                 */
                if (ext_left != -1)
                        nsp.sp_left = sc->ext_left = ext_left;
                else if (sc->ext_left != 0)
                        nsp.sp_left = sc->ext_left;

                if (ext_right != -1)
                        nsp.sp_right = sc->ext_right = ext_right;
                else if (sc->ext_right != 0)
                        nsp.sp_right = sc->ext_right;

                if (ext_middle != -1)
                        nsp.sp_middle = sc->ext_middle = ext_middle;
                else if (sc->ext_middle != 0)
                        nsp.sp_middle = sc->ext_middle;

                if (ext_up != -1)
                        nsp.sp_up = sc->ext_up = ext_up;
                else if (sc->ext_up != 0)
                        nsp.sp_up = sc->ext_up;

                if (ext_down != -1)
                        nsp.sp_down = sc->ext_down = ext_down;
                else if (sc->ext_down != 0)
                        nsp.sp_down = sc->ext_down;

                switch (synaptics_up_down_emul) {
                case 1:
                        /* Do middle button emulation using up/down buttons */
                        nsp.sp_middle = nsp.sp_up | nsp.sp_down;
                        nsp.sp_up = nsp.sp_down = 0;
                        break;
                case 3:
                        /* Do left/right button emulation using up/down buttons */
                        nsp.sp_left = nsp.sp_left | nsp.sp_up;
                        nsp.sp_right = nsp.sp_right | nsp.sp_down;
                        nsp.sp_up = nsp.sp_down = 0;
                        break;
                default:
                        /*
                         * Don't do any remapping...
                         * Z-axis emulation is handled in pms_synaptics_process_packet
                         */
                        break;
                }
        }

        /* set the finger count only if we haven't seen an extended-w
         * finger count status
         */
        if (nsp.sp_finger_status == 0)
                nsp.sp_finger_count = pms_synaptics_get_fingers(psc, nsp.sp_w,
                    nsp.sp_z);

skip_position:
        DPRINTF(20, sc,
            "synaptics_parse: sp_x %d sp_y %d sp_z %d, sp_sx %d, sp_sy %d, "
            "sp_sz %d, sp_w %d sp_finger_count %d, sp_primary %d, "
            "sp_secondary %d, v %d, primary_finger %d, secondary_finger %d\n",
            nsp.sp_x, nsp.sp_y, nsp.sp_z, nsp.sp_sx,
            nsp.sp_sy, nsp.sp_sz, nsp.sp_w, nsp.sp_finger_count, 
            nsp.sp_primary, nsp.sp_secondary, v, primary_finger,
            secondary_finger);

        pms_synaptics_process_packet(psc, &nsp);

        /* Clear fingers */
        if ((nsp.sp_primary && nsp.sp_finger_count <= 1) || nsp.sp_secondary) {
                nsp.sp_primary = 0;
                nsp.sp_secondary = 0;
                nsp.sp_finger_status = 0;
        }

        memcpy(&packet, &nsp, sizeof(packet));
}

/*
 * Passthrough is used for e.g. TrackPoints and additional pointing
 * devices connected to a Synaptics touchpad.
 */
static void
pms_synaptics_passthrough(struct pms_softc *psc)
{
        int dx, dy, dz;
        int buttons, changed;
        int s;

        buttons = ((psc->packet[1] & PMS_LBUTMASK) ? 0x20 : 0) |
                ((psc->packet[1] & PMS_MBUTMASK) ? 0x40 : 0) |
                ((psc->packet[1] & PMS_RBUTMASK) ? 0x80 : 0);

        dx = psc->packet[4];
        if (dx >= 128)
                dx -= 256;
        if (dx == -128)
                dx = -127;

        dy = psc->packet[5];
        if (dy >= 128)
                dy -= 256;
        if (dy == -128)
                dy = -127;

        dz = 0;

        changed = buttons ^ (psc->buttons & 0xe0);
        psc->buttons ^= changed;

        if (dx || dy || dz || changed) {
                s = spltty();
                /*
                 * If the middle button is held, interpret movement as
                 * scrolling.
                 */
                if (synaptics_aux_mid_button_scroll &&
                    dy && (psc->buttons & 0x42)) {
                        wsmouse_precision_scroll(psc->sc_wsmousedev, dx, dy);
                } else {
                        buttons = (psc->buttons & 0x1f) | ((psc->buttons >> 5) & 0x7);
                        wsmouse_input(psc->sc_wsmousedev,
                                buttons, dx, dy, dz, 0,
                                WSMOUSE_INPUT_DELTA);
                }
                splx(s);
        }
}

static void
pms_synaptics_input(void *vsc, int data)
{
        struct pms_softc *psc = vsc;
        struct timeval diff;

        if (!psc->sc_enabled) {
                /* Interrupts are not expected. Discard the byte. */
                return;
        }

        getmicrouptime(&psc->current);

        if (psc->inputstate > 0) {
                timersub(&psc->current, &psc->last, &diff);
                if (diff.tv_sec > 0 || diff.tv_usec >= 40000) {
                        device_printf(psc->sc_dev,
                            "pms_synaptics_input: unusual delay (%ld.%06ld s), "
                            "scheduling reset\n",
                            (long)diff.tv_sec, (long)diff.tv_usec);
                        psc->inputstate = 0;
                        psc->sc_enabled = 0;
                        wakeup(&psc->sc_enabled);
                        return;
                }
        }
        psc->last = psc->current;

        switch (psc->inputstate) {
        case -5:
        case -4:
        case -3:
        case -2:
        case -1:
        case 0:
                if ((data & 0xc8) != 0x80) {
                        device_printf(psc->sc_dev,
                            "pms_synaptics_input: 0x%02x out of sync\n", data);
                        /* use negative counts to limit resync phase */
                        psc->inputstate--;
                        return; /* not in sync yet, discard input */
                }
                psc->inputstate = 0;
                /*FALLTHROUGH*/

        case -6:
        case 3:
                if ((data & 8) == 8) {
                        device_printf(psc->sc_dev,
                            "pms_synaptics_input: dropped in relative mode, reset\n");
                        psc->inputstate = 0;
                        psc->sc_enabled = 0;
                        wakeup(&psc->sc_enabled);
                        return;
                }
        }
        if (psc->inputstate >= sizeof(psc->packet))
                panic("inputstate should never be %d", psc->inputstate);

        psc->packet[psc->inputstate++] = data & 0xff;
        if (psc->inputstate == 6) {
                struct synaptics_softc *sc = &psc->u.synaptics;
                DPRINTF(10, sc, "synaptics: packet: 0x%02x%02x%02x%02x%02x%02x\n",
                        psc->packet[0], psc->packet[1], psc->packet[2],
                        psc->packet[3], psc->packet[4], psc->packet[5]);
                /*
                 * We have a complete packet.
                 * Extract the pertinent details.
                 */
                psc->inputstate = 0;
                if ((psc->packet[0] & 0xfc) == 0x84 &&
                    (psc->packet[3] & 0xcc) == 0xc4) {
                        /* W = SYNAPTICS_WIDTH_PASSTHROUGH, PS/2 passthrough */
                        pms_synaptics_passthrough(psc);
                } else {
                        pms_synaptics_parse(psc);
                }
        }
}

static inline int
synaptics_finger_detect(struct synaptics_softc *sc, struct synaptics_packet *sp,
    int *palmp)
{
        int fingers;

        /* Assume no palm */
        *palmp = 0;

        /*
         * Apply some hysteresis when checking for a finger.
         * When the finger is first applied, we ignore it until the
         * pressure exceeds the 'high' threshold. The finger is considered
         * removed only when pressure falls beneath the 'low' threshold.
         */
        if ((sc->prev_fingers == 0 && sp->sp_z > synaptics_finger_high) ||
            (sc->prev_fingers != 0 && sp->sp_z > synaptics_finger_low))
                fingers = 1;
        else
                fingers = 0;

        /*
         * If the pad can't do palm detection, skip the rest.
         */
        if (fingers == 0 || (sc->flags & SYN_FLAG_HAS_PALM_DETECT) == 0)
                return (fingers);

        /*
         * Palm detection
         */
        if (sp->sp_z > SYNAPTICS_FINGER_FLAT &&
            sp->sp_w >= SYNAPTICS_WIDTH_PALM_MIN)
                *palmp = 1;

        if (sc->prev_fingers == 0 &&
            (sp->sp_z > SYNAPTICS_FINGER_FLAT ||
             sp->sp_w >= SYNAPTICS_WIDTH_PALM_MIN)) {
                /*
                 * Contact area or pressure is too great to be a finger.
                 * Just ignore it for now.
                 */
                return (0);
        }

        /*
         * Detect 2 and 3 fingers if supported, but only if multiple
         * fingers appear within the tap gesture time period.
         */
        if ((sc->flags & SYN_FLAG_HAS_MULTI_FINGER) &&
            ((SYN_TIME(sc, sc->gesture_start_packet)
             < synaptics_gesture_length) ||
            SYN_TIME(sc, sc->gesture_start_packet)
             < synaptics_gesture_length)) {
                switch (sp->sp_w) {
                case SYNAPTICS_WIDTH_TWO_FINGERS:
                        fingers = 2;
                        break;

                case SYNAPTICS_WIDTH_THREE_OR_MORE:
                        fingers = 3;
                        break;

                default:
                        /*
                         * The width value can report spurious single-finger
                         * events after a multi-finger event.
                         */
                        fingers = sc->prev_fingers <= 1 ? 1 : sc->prev_fingers;
                        break;
                }
        }

        return (fingers);
}

static inline void
synaptics_gesture_detect(struct synaptics_softc *sc,
    struct synaptics_packet *sp, int fingers)
{
        int gesture_len, gesture_buttons;
        int set_buttons;

        gesture_len = SYN_TIME(sc, sc->gesture_start_packet);
        gesture_buttons = sc->gesture_buttons;

        if (fingers > 0 && (fingers == sc->prev_fingers)) {
                /* Finger is still present */
                sc->gesture_move_x = abs(sc->gesture_start_x - sp->sp_x);
                sc->gesture_move_y = abs(sc->gesture_start_y - sp->sp_y);
        } else
        if (fingers && sc->prev_fingers == 0) {
                /*
                 * Finger was just applied.
                 * If the previous gesture was a single-click, set things
                 * up to deal with a possible drag or double-click gesture.
                 * Basically, if the finger is removed again within
                 * 'synaptics_gesture_length' packets, this is treated
                 * as a double-click. Otherwise we will emulate holding
                 * the left button down whilst dragging the mouse.
                 */
                if (SYN_IS_SINGLE_TAP(sc->gesture_type))
                        sc->gesture_type |= SYN_GESTURE_DRAG;

                sc->gesture_start_x = abs(sp->sp_x);
                sc->gesture_start_y = abs(sp->sp_y);
                sc->gesture_move_x = 0;
                sc->gesture_move_y = 0;
                sc->gesture_start_packet = sc->total_packets;

                DPRINTF(10, sc, "Finger applied:"
                    " gesture_start_x: %d"
                    " gesture_start_y: %d\n",
                    sc->gesture_start_x, sc->gesture_start_y);
        } else
        if (fingers == 0 && sc->prev_fingers != 0) {
                /*
                 * Finger was just removed.
                 * Check if the contact time and finger movement were
                 * small enough to qualify as a gesture.
                 * Ignore finger movement if multiple fingers were
                 * detected (the pad may report coordinates for any
                 * of the fingers).
                 */

                DPRINTF(10, sc, "Finger removed: gesture_len: %d (%d)\n",
                    gesture_len, synaptics_gesture_length);
                DPRINTF(10, sc, "gesture_move_x: %d (%d) sp_x: %d\n",
                    sc->gesture_move_x, synaptics_gesture_move, abs(sp->sp_x));
                DPRINTF(10, sc, "gesture_move_y: %d (%d) sp_y: %d\n",
                    sc->gesture_move_y, synaptics_gesture_move, abs(sp->sp_y));

                if (gesture_len < synaptics_gesture_length &&
                    ((sc->gesture_move_x < synaptics_gesture_move &&
                     sc->gesture_move_y < synaptics_gesture_move))) {
                        /*
                         * Looking good so far.
                         */
                        if (SYN_IS_DRAG(sc->gesture_type)) {
                                /*
                                 * Promote this gesture to double-click.
                                 */
                                sc->gesture_type |= SYN_GESTURE_DOUBLE;
                                sc->gesture_type &= ~SYN_GESTURE_SINGLE;
                        } else {
                                /*
                                 * Single tap gesture. Set the tap length timer
                                 * and flag a single-click.
                                 */
                                sc->gesture_tap_packet = sc->total_packets;
                                sc->gesture_type |= SYN_GESTURE_SINGLE;

                                /*
                                 * The gesture can be modified depending on
                                 * the number of fingers detected.
                                 *
                                 * 1: Normal left button emulation.
                                 * 2: Either middle button or right button
                                 *    depending on the value of the two_fingers
                                 *    sysctl variable.
                                 * 3: Right button.
                                 */
                                switch (sc->prev_fingers) {
                                case 2:
                                        if (synaptics_two_fingers_emul == 1)
                                                gesture_buttons |= PMS_RBUTMASK;
                                        else
                                        if (synaptics_two_fingers_emul == 2)
                                                gesture_buttons |= PMS_MBUTMASK;
                                        break;
                                case 3:
                                        gesture_buttons |= PMS_RBUTMASK;
                                        break;
                                default:
                                        gesture_buttons |= PMS_LBUTMASK;
                                        break;
                                }
                        }
                }

                /*
                 * Always clear drag state when the finger is removed.
                 */
                sc->gesture_type &= ~SYN_GESTURE_DRAG;
        }

        if (sc->gesture_type == 0) {
                /*
                 * There is no gesture in progress.
                 * Clear emulated button state.
                 */
                sc->gesture_buttons = 0;
                return;
        }

        /*
         * A gesture is in progress.
         */
        set_buttons = 0;

        if (SYN_IS_SINGLE_TAP(sc->gesture_type)) {
                /*
                 * Single-click.
                 * Activate the relevant button(s) until the
                 * gesture tap timer has expired.
                 */
                if (SYN_TIME(sc, sc->gesture_tap_packet) <
                    synaptics_gesture_length)
                        set_buttons = 1;
                else
                        sc->gesture_type &= ~SYN_GESTURE_SINGLE;
                DPRINTF(10, sc, "synaptics_gesture: single tap, buttons %d\n",
                    set_buttons);
                DPRINTF(10, sc, "synaptics_gesture: single tap, tap at %d, current %d\n",
                    sc->gesture_tap_packet, sc->total_packets);
                DPRINTF(10, sc, "synaptics_gesture: single tap, tap_time %d, gesture len %d\n",
                    SYN_TIME(sc, sc->gesture_tap_packet), synaptics_gesture_length);
        } else
        if (SYN_IS_DOUBLE_TAP(sc->gesture_type) && sc->prev_fingers == 0) {
                /*
                 * Double-click.
                 * Activate the relevant button(s) once.
                 */
                set_buttons = 1;
                sc->gesture_type &= ~SYN_GESTURE_DOUBLE;
        }

        if (set_buttons || SYN_IS_DRAG(sc->gesture_type)) {
                /*
                 * Single-click and drag.
                 * Maintain button state until the finger is removed.
                 */
                sp->sp_left |= gesture_buttons & PMS_LBUTMASK;
                sp->sp_right |= gesture_buttons & PMS_RBUTMASK;
                sp->sp_middle |= gesture_buttons & PMS_MBUTMASK;
        }

        sc->gesture_buttons = gesture_buttons;
}

static inline int
synaptics_filter_policy(struct synaptics_softc *sc, int finger, int *history,
                        int value, u_int count)
{
        int a, b, rv;

        /*
         * Once we've accumulated at least SYN_HIST_SIZE values, combine
         * each new value with the previous two and return the average.
         *
         * This is necessary when the touchpad is operating in 80 packets
         * per second mode, as it performs little internal filtering on
         * reported values.
         *
         * Using a rolling average helps to filter out jitter caused by
         * tiny finger movements.
         */
        if (count >= SYN_HIST_SIZE) {
                a = (history[(count - 2) % SYN_HIST_SIZE] +
                     history[(count - 1) % SYN_HIST_SIZE]) / 2;

                b = (value + history[(count - 1) % SYN_HIST_SIZE]) / 2;

                rv = b - a;

                /*
                 * Don't report the movement if it's below a certain
                 * threshold.
                 */
                if (abs(rv) < synaptics_movement_threshold)
                        rv = 0;
        } else
                rv = 0;

        /*
         * Add the new value to the history buffer.
         */
        history[(count + 0) % SYN_HIST_SIZE] = value;

        return (rv);
}

/* Edge detection */
#define SYN_EDGE_TOP            1
#define SYN_EDGE_BOTTOM         2
#define SYN_EDGE_LEFT           4
#define SYN_EDGE_RIGHT          8

static inline int
synaptics_check_edge(int x, int y)
{
        int rv = 0;

        if (x < synaptics_edge_left)
                rv |= SYN_EDGE_LEFT;
        else
        if (x > synaptics_edge_right)
                rv |= SYN_EDGE_RIGHT;

        if (y < synaptics_edge_bottom)
                rv |= SYN_EDGE_BOTTOM;
        else
        if (y > synaptics_edge_top)
                rv |= SYN_EDGE_TOP;

        return (rv);
}

static inline int
synaptics_edge_motion(struct synaptics_softc *sc, int delta, int dir)
{

        /*
         * When edge motion is enabled, synaptics_edge_motion_delta is
         * combined with the current delta, together with the direction
         * in which to simulate the motion. The result is added to
         * the delta derived from finger movement. This provides a smooth
         * transition from finger movement to edge motion.
         */
        delta = synaptics_edge_motion_delta + (dir * delta);
        if (delta < 0)
                return (0);
        if (delta > synaptics_edge_motion_delta)
                return (synaptics_edge_motion_delta);
        return (delta);
}

static inline int
synaptics_scale(int delta, int scale, int *remp)
{
        int rv;

        /*
         * Scale the raw delta in Synaptics coordinates (0-6143) into
         * something more reasonable by dividing the raw delta by a
         * scale factor. Any remainder from the previous scale result
         * is added to the current delta before scaling.
         * This prevents loss of resolution for very small/slow
         * movements of the finger.
         */
        delta += *remp;
        rv = delta / scale;
        *remp = delta % scale;

        return (rv);
}

static inline void
synaptics_movement(struct synaptics_softc *sc, struct synaptics_packet *sp,
    int *dxp, int *dyp, int *dzp, int *sdxp, int *sdyp, int *sdzp)
{
        int dx, dy, dz, sdx, sdy, sdz, edge;

        dx = dy = dz = sdx = sdy = sdz = 0;

        /*
         * Compute the next values of dx, dy, dz, sdx, sdy, sdz.
         */
        dx = synaptics_filter_policy(sc, 0,
            sc->history_x[SYN_PRIMARY_FINGER], sp->sp_x,
            sc->packet_count[SYN_PRIMARY_FINGER]);
        dy = synaptics_filter_policy(sc, 0,
            sc->history_y[SYN_PRIMARY_FINGER], sp->sp_y,
            sc->packet_count[SYN_PRIMARY_FINGER]);
        sc->packet_count[SYN_PRIMARY_FINGER]++;

        if (sp->sp_finger_count > 1) {
                sdx = synaptics_filter_policy(sc, 1,
                    sc->history_x[SYN_SECONDARY_FINGER], sp->sp_sx,
                    sc->packet_count[SYN_SECONDARY_FINGER]);
                sdy = synaptics_filter_policy(sc, 1,
                    sc->history_y[SYN_SECONDARY_FINGER], sp->sp_sy,
                    sc->packet_count[SYN_SECONDARY_FINGER]);
                sc->packet_count[SYN_SECONDARY_FINGER]++;
                DPRINTF(10, sc, "synaptics_movement: dx %d dy %d sdx %d sdy %d\n",
                    dx, dy, sdx, sdy);
        }

        /*
         * If we're dealing with a drag gesture, and the finger moves to
         * the edge of the touchpad, apply edge motion emulation if it
         * is enabled.
         */
        if (synaptics_edge_motion_delta && SYN_IS_DRAG(sc->gesture_type)) {
                edge = synaptics_check_edge(sp->sp_x, sp->sp_y);

                if (edge & SYN_EDGE_LEFT)
                        dx -= synaptics_edge_motion(sc, dx, 1);
                if (edge & SYN_EDGE_RIGHT)
                        dx += synaptics_edge_motion(sc, dx, -1);
                if (edge & SYN_EDGE_BOTTOM)
                        dy -= synaptics_edge_motion(sc, dy, 1);
                if (edge & SYN_EDGE_TOP)
                        dy += synaptics_edge_motion(sc, dy, -1);

                if (sp->sp_finger_count > 1) {
                        edge = synaptics_check_edge(sp->sp_sx, sp->sp_sy);

                        if (edge & SYN_EDGE_LEFT)
                                sdx -= synaptics_edge_motion(sc, sdx, 1);
                        if (edge & SYN_EDGE_RIGHT)
                                sdx += synaptics_edge_motion(sc, sdx, -1);
                        if (edge & SYN_EDGE_BOTTOM)
                                sdy -= synaptics_edge_motion(sc, sdy, 1);
                        if (edge & SYN_EDGE_TOP)
                                sdy += synaptics_edge_motion(sc, sdy, -1);
                }
        }

        /*
         * Apply scaling to the deltas
         */
        dx = synaptics_scale(dx, synaptics_scale_x,
            &sc->rem_x[SYN_PRIMARY_FINGER]);
        dy = synaptics_scale(dy, synaptics_scale_y,
            &sc->rem_y[SYN_PRIMARY_FINGER]);
        dz = synaptics_scale(dz, synaptics_scale_z,
            &sc->rem_z[SYN_PRIMARY_FINGER]);

        if (sp->sp_finger_count > 1) {
                sdx = synaptics_scale(sdx, synaptics_scale_x,
                    &sc->rem_x[SYN_SECONDARY_FINGER]);
                sdy = synaptics_scale(sdy, synaptics_scale_y,
                    &sc->rem_y[SYN_SECONDARY_FINGER]);
                sdz = synaptics_scale(sdz, synaptics_scale_z,
                    &sc->rem_z[SYN_SECONDARY_FINGER]);

                DPRINTF(10, sc,
                    "synaptics_movement 2: dx %d dy %d sdx %d sdy %d\n",
                    dx, dy, sdx, sdy);
        }

        /*
         * Clamp deltas to specified maximums.
         */
        if (abs(dx) > synaptics_max_speed_x)
                dx = ((dx >= 0)? 1 : -1) * synaptics_max_speed_x;
        if (abs(dy) > synaptics_max_speed_y)
                dy = ((dy >= 0)? 1 : -1) * synaptics_max_speed_y;
        if (abs(dz) > synaptics_max_speed_z)
                dz = ((dz >= 0)? 1 : -1) * synaptics_max_speed_z;

        if (sp->sp_finger_count > 1) {
                if (abs(sdx) > synaptics_max_speed_x)
                        sdx = ((sdx >= 0)? 1 : -1) * synaptics_max_speed_x;
                if (abs(dy) > synaptics_max_speed_y)
                        sdy = ((sdy >= 0)? 1 : -1) * synaptics_max_speed_y;
                if (abs(sdz) > synaptics_max_speed_z)
                        sdz = ((sdz >= 0)? 1 : -1) * synaptics_max_speed_z;
        }

        *dxp = dx;
        *dyp = dy;
        *dzp = dz;
        *sdxp = sdx;
        *sdyp = sdy;
        *sdzp = sdz;

}

static void
pms_synaptics_process_packet(struct pms_softc *psc, struct synaptics_packet *sp)
{
        struct synaptics_softc *sc = &psc->u.synaptics;
        int dx, dy, dz, sdx, sdy, sdz;
        int fingers, palm, buttons, changed;
        int s;

        sdx = sdy = sdz = 0;

        /*
         * Do Z-axis emulation using up/down buttons if required.
         * Note that the pad will send a one second burst of packets
         * when an up/down button is pressed and held. At the moment
         * we don't deal with auto-repeat, so convert the burst into
         * a one-shot.
         */
        dz = 0;
        if (synaptics_up_down_emul == 2) {
                if (sc->up_down == 0) {
                        if (sp->sp_up && sp->sp_down) {
                                sp->sp_middle = 1;
                        } else if (sp->sp_up) {
                                dz = -synaptics_up_down_motion_delta;
                        } else if (sp->sp_down) {
                                dz = synaptics_up_down_motion_delta;
                        }
                }

                sc->up_down = sp->sp_up | sp->sp_down;
                sp->sp_up = sp->sp_down = 0;
        }

        /*
         * Determine whether or not a finger is on the pad.
         * On some pads, this will return the number of fingers
         * detected.
         */
        fingers = synaptics_finger_detect(sc, sp, &palm);

        /*
         * Do gesture processing only if we didn't detect a palm.
         */
        if (palm == 0 && synaptics_tap_to_click)
                synaptics_gesture_detect(sc, sp, fingers);
        else
                sc->gesture_type = sc->gesture_buttons = 0;

        /*
         * Determine what buttons to report
         */
        buttons = (sp->sp_left ? 0x1 : 0) |
            (sp->sp_middle ? 0x2 : 0) |
            (sp->sp_right ? 0x4 : 0) |
            (sp->sp_up ? 0x8 : 0) |
            (sp->sp_down ? 0x10 : 0);
        changed = buttons ^ (psc->buttons & 0x1f);
        psc->buttons ^= changed;

        sc->prev_fingers = fingers;

        /*
         * Do movement processing IFF we have a single finger and no palm or
         * a secondary finger and no palm.
         */
        if (palm == 0 && synaptics_movement_enable) {
                if (fingers > 0) {
                        synaptics_movement(sc, sp, &dx, &dy, &dz, &sdx, &sdy,
                            &sdz);

                        /*
                         * Check if there are two fingers, if there are then
                         * check if we have a clickpad, if we do then we
                         * don't scroll iff one of the fingers is in the
                         * button region.  Otherwise interpret as a scroll
                         */
                        if (sp->sp_finger_count >= 2 && sc->gesture_type == 0 ) {
                                if (!(sc->flags & SYN_FLAG_HAS_ONE_BUTTON_CLICKPAD) ||
                                    ((sc->flags & SYN_FLAG_HAS_ONE_BUTTON_CLICKPAD) &&
                                    (sp->sp_y > synaptics_button_boundary)  &&
                                    (sp->sp_sy > synaptics_button_boundary))) {
                                        s = spltty();
                                        wsmouse_precision_scroll(
                                            psc->sc_wsmousedev, dx, dy);
                                        splx(s);
                                        return;
                                }
                        }

                        /*
                         * Allow user to turn off movements in the button
                         * region of a click pad.
                         */
                        if (sc->flags & SYN_FLAG_HAS_ONE_BUTTON_CLICKPAD) {
                                if ((sp->sp_y < synaptics_button_boundary) &&
                                    (!synaptics_button_region_movement)) {
                                        dx = dy = dz = 0;
                                }

                                if ((sp->sp_sy < synaptics_button_boundary) &&
                                    (!synaptics_button_region_movement)) {
                                        sdx = sdy = sdz = 0;
                                }
                        }

                        /* Now work out which finger to report, just
                         * go with the one that has moved the most.
                         */
                        if ((abs(dx) + abs(dy) + abs(dz)) <
                            (abs(sdx) + abs(sdy) + abs(sdz))) {
                                /* secondary finger wins */
                                dx = sdx;
                                dy = sdy;
                                dz = sdz;
                        }
                } else {
                        /*
                         * No valid finger. Therefore no movement.
                         */
                        sc->rem_x[SYN_PRIMARY_FINGER] = 0;
                        sc->rem_y[SYN_PRIMARY_FINGER] = 0;
                        sc->rem_x[SYN_SECONDARY_FINGER] = 0;
                        sc->rem_y[SYN_SECONDARY_FINGER] = 0;
                        dx = dy = 0;

                        sc->packet_count[SYN_PRIMARY_FINGER] = 0;
                        sc->packet_count[SYN_SECONDARY_FINGER] = 0;
                }
        } else {
                /*
                 * No valid finger. Therefore no movement.
                 */
                sc->rem_x[SYN_PRIMARY_FINGER] = 0;
                sc->rem_y[SYN_PRIMARY_FINGER] = 0;
                sc->rem_z[SYN_PRIMARY_FINGER] = 0;
                dx = dy = dz = 0;
        }

        DPRINTF(10, sc,
            "pms_synaptics_process_packet: dx %d dy %d dz %d sdx %d sdy %d sdz %d\n",
            dx, dy, dz, sdx, sdy, sdz);

        /*
         * Pass the final results up to wsmouse_input() if necessary.
         */
        if (dx || dy || dz || changed) {
                buttons = (psc->buttons & 0x1f) | ((psc->buttons >> 5) & 0x7);
                s = spltty();
                wsmouse_input(psc->sc_wsmousedev,
                                buttons,
                                dx, dy, dz, 0,
                                WSMOUSE_INPUT_DELTA);
                splx(s);
        }
}