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[netbsd-mini2440.git] / sys / dev / pckbport / synaptics.c

/*      $NetBSD: synaptics.c,v 1.20 2008/03/15 18:46:22 cube 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 1.20 2008/03/15 18:46:22 cube 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/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) */
        u_char  sp_w;           /* W (contact patch width) */
        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 int pms_synaptics_send_command(pckbport_tag_t, pckbport_slot_t, u_char);
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);

/* Controled by sysctl. */
static int synaptics_up_down_emul = 2;
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_two_fingers_emul = 0;
static int synaptics_scale_x = 16;
static int synaptics_scale_y = 16;
static int synaptics_max_speed_x = 32;
static int synaptics_max_speed_y = 32;
static int synaptics_movement_threshold = 4;

/* Sysctl nodes. */
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_two_fingers_emul_nodenum;
static int synaptics_scale_x_nodenum;
static int synaptics_scale_y_nodenum;
static int synaptics_max_speed_x_nodenum;
static int synaptics_max_speed_y_nodenum;
static int synaptics_movement_threshold_nodenum;

int
pms_synaptics_probe_init(void *vsc)
{
        struct pms_softc *psc = vsc;
        struct synaptics_softc *sc = &psc->u.synaptics;
        u_char cmd[2], resp[3];
        int res, ver_minor, ver_major;
        struct sysctllog *clog = NULL;

        res = pms_synaptics_send_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) {
#ifdef SYNAPTICSDEBUG
                aprint_normal_dev(psc->sc_dev,
                    "synaptics_probe: Identify Touchpad error.\n");
#endif
                /*
                 * Reset device in case the probe confused it.
                 */
 doreset:
                cmd[0] = PMS_RESET;
                (void) pckbport_poll_cmd(psc->sc_kbctag, psc->sc_kbcslot, cmd,
                    1, 2, resp, 1);
                return (res);
        }

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

        sc->flags = 0;

        /* 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 = pms_synaptics_send_command(psc->sc_kbctag, psc->sc_kbcslot,
            SYNAPTICS_READ_CAPABILITIES);
        cmd[0] = PMS_SEND_DEV_STATUS;
        res |= pckbport_poll_cmd(psc->sc_kbctag, psc->sc_kbcslot, cmd, 1, 3,
            resp, 0);
        if (res) {
                /* Hmm, failed to get capabilites. */
                aprint_error_dev(psc->sc_dev,
                    "synaptics_probe: Failed to query capabilities.\n");
                goto doreset;
        }

        sc->caps = (resp[0] << 8) | resp[2];

        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) {
#ifdef SYNAPTICSDEBUG
                aprint_normal_dev(psc->sc_dev,
                    "synaptics_probe: Capabilities 0x%04x.\n", sc->caps);
#endif
                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;

                /* Ask about extra buttons to detect up/down. */
                if (sc->caps & SYNAPTICS_CAP_EXTNUM) {
                        res = pms_synaptics_send_command(psc->sc_kbctag,
                            psc->sc_kbcslot, SYNAPTICS_EXTENDED_QUERY);
                        cmd[0] = PMS_SEND_DEV_STATUS;
                        res |= pckbport_poll_cmd(psc->sc_kbctag,
                            psc->sc_kbcslot, cmd, 1, 3, resp, 0);
#ifdef SYNAPTICSDEBUG
                        if (res == 0)
                                aprint_normal_dev(psc->sc_dev,
                                    "synaptics_probe: Extended "
                                    "Capabilities 0x%02x.\n", resp[1]);
#endif
                        if (!res && (resp[1] >> 4) >= 2) {
                                /* Yes. */
                                sc->flags |= SYN_FLAG_HAS_UP_DOWN_BUTTONS;
                        }
                }
        }

        if (sc->flags) {
                const char comma[] = ", ";
                const char *sep = "";
                aprint_normal_dev(psc->sc_dev, "");
                if (sc->flags & SYN_FLAG_HAS_MIDDLE_BUTTON) {
                        aprint_normal("%sMiddle button", sep);
                        sep = comma;
                }
                if (sc->flags & SYN_FLAG_HAS_BUTTONS_4_5) {
                        aprint_normal("%sButtons 4/5", sep);
                        sep = comma;
                }
                if (sc->flags & SYN_FLAG_HAS_UP_DOWN_BUTTONS) {
                        aprint_normal("%sUp/down buttons", sep);
                        sep = comma;
                }
                if (sc->flags & SYN_FLAG_HAS_PALM_DETECT) {
                        aprint_normal("%sPalm detect", sep);
                        sep = comma;
                }
                if (sc->flags & SYN_FLAG_HAS_MULTI_FINGER)
                        aprint_normal("%sMulti-finger", sep);

                aprint_normal("\n");
        }

done:
        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 cmd[2];
        int res;

        /*
         * Enable Absolute mode with W (width) reporting, and set
         * the packet rate to maximum (80 packets per second).
         */
        res = pms_synaptics_send_command(psc->sc_kbctag, psc->sc_kbcslot,
            SYNAPTICS_MODE_ABSOLUTE | SYNAPTICS_MODE_W | SYNAPTICS_MODE_RATE);
        cmd[0] = PMS_SET_SAMPLE;
        cmd[1] = 0x14; /* doit */
        res |= pckbport_enqueue_cmd(psc->sc_kbctag, psc->sc_kbcslot, cmd, 2, 0,
            1, NULL);
        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->rem_x = sc->rem_y = 0;
        sc->movement_history = 0;
        if (res) {
                aprint_error_dev(psc->sc_dev,
                    "synaptics_enable: Error enabling device.\n");
        }
}

void
pms_synaptics_resume(void *vsc)
{
        struct pms_softc *psc = vsc;
        unsigned char cmd[1],resp[2] = { 0,0 };
        int res;

        cmd[0] = PMS_RESET;
        res = pckbport_poll_cmd(psc->sc_kbctag, psc->sc_kbcslot, cmd, 1, 2,
            resp, 1);
        aprint_debug_dev(psc->sc_dev,
            "pms_synaptics_resume: reset on resume %d 0x%02x 0x%02x\n",
            res, resp[0], resp[1]);
}

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

        if ((rc = sysctl_createv(clog, 0, NULL, NULL,
            CTLFLAG_PERMANENT, CTLTYPE_NODE, "hw", NULL,
            NULL, 0, NULL, 0, CTL_HW, CTL_EOL)) != 0)
                goto err;

        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, "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, "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, "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;
        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 ||
            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) {
                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) {
                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
                return (EINVAL);

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

        return (0);
}

static int
pms_synaptics_send_command(pckbport_tag_t tag, pckbport_slot_t slot,
    u_char syn_cmd)
{
        u_char cmd[2];
        int res;

        /*
         * Need to send 4 Set Resolution commands, with the argument
         * encoded in the bottom most 2 bits.
         */
        cmd[0] = PMS_SET_RES;
        cmd[1] = syn_cmd >> 6;
        res = pckbport_poll_cmd(tag, slot, cmd, 2, 0, NULL, 0);

        cmd[0] = PMS_SET_RES;
        cmd[1] = (syn_cmd & 0x30) >> 4;
        res |= pckbport_poll_cmd(tag, slot, cmd, 2, 0, NULL, 0);

        cmd[0] = PMS_SET_RES;
        cmd[1] = (syn_cmd & 0x0c) >> 2;
        res |= pckbport_poll_cmd(tag, slot, cmd, 2, 0, NULL, 0);

        cmd[0] = PMS_SET_RES;
        cmd[1] = (syn_cmd & 0x03);
        res |= pckbport_poll_cmd(tag, slot, cmd, 2, 0, NULL, 0);

        return (res);
}

/* 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 sp;

        /* Absolute X/Y coordinates of finger */
        sp.sp_x = psc->packet[4] + ((psc->packet[1] & 0x0f) << 8) +
           ((psc->packet[3] & 0x10) << 8);
        sp.sp_y = psc->packet[5] + ((psc->packet[1] & 0xf0) << 4) +
           ((psc->packet[3] & 0x20) << 7);

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

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

        /* Left/Right button handling. */
        sp.sp_left = psc->packet[0] & PMS_LBUTMASK;
        sp.sp_right = psc->packet[0] & PMS_RBUTMASK;

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

        /* Middle button. */
        if (sc->flags & SYN_FLAG_HAS_MIDDLE_BUTTON) {
                /* Old style Middle Button. */
                sp.sp_middle = (psc->packet[0] & PMS_LBUTMASK) ^
                    (psc->packet[3] & PMS_LBUTMASK);
        } else
        if (synaptics_up_down_emul == 1) {
                /* Do middle button emulation using up/down buttons */
                sp.sp_middle = sp.sp_up | sp.sp_down;
                sp.sp_up = sp.sp_down = 0;
        } else
                sp.sp_middle = 0;

        pms_synaptics_process_packet(psc, &sp);
}

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) {
                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);
        }
}

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) {
                        aprint_debug_dev(psc->sc_dev,
                            "pms_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 0:
                if ((data & 0xc8) != 0x80) {
#ifdef SYNAPTICSDEBUG
                        aprint_normal_dev(psc->sc_dev,
                            "pms_input: 0x%02x out of sync\n", data);
#endif
                        return; /* not in sync yet, discard input */
                }
                /*FALLTHROUGH*/

        case 3:
                if ((data & 8) == 8) {
#ifdef SYNAPTICSDEBUG
                        aprint_normal_dev(psc->sc_dev,
                            "pms_input: dropped in relative mode, reset\n");
#endif
                        psc->inputstate = 0;
                        psc->sc_enabled = 0;
                        wakeup(&psc->sc_enabled);
                        return;
                }
        }

        psc->packet[psc->inputstate++] = data & 0xff;
        if (psc->inputstate == 6) {
                /*
                 * We have a complete packet.
                 * Extract the pertinent details.
                 */
                psc->inputstate = 0;

                if ((psc->packet[0] & 0xfc) == 0x84 &&
                    (psc->packet[3] & 0xcc) == 0xc4) {
                        /* 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) {
                switch (sp->sp_w) {
                case SYNAPTICS_WIDTH_TWO_FINGERS:
                        fingers = 2;
                        break;

                case SYNAPTICS_WIDTH_THREE_OR_MORE:
                        fingers = 3;
                        break;

                case SYNAPTICS_WIDTH_PEN:
                        fingers = 1;
                        break;

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

        return (fingers);
}

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

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

        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 = sp->sp_x;
                sc->gesture_start_y = sp->sp_y;
                sc->gesture_start_packet = sc->total_packets;
        } 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).
                 */
                gesture_move_x = abs(sc->gesture_start_x - sp->sp_x);
                gesture_move_y = abs(sc->gesture_start_y - sp->sp_y);

                if (gesture_len < synaptics_gesture_length &&
                    (sc->prev_fingers > 1 ||
                    (gesture_move_x < synaptics_gesture_move &&
                     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;
        } 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 *history, int value)
{
        int a, b, rv, count;

        count = sc->total_packets;

        /*
         * 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 (sc->movement_history >= SYN_HIST_SIZE) {
                a = (history[(count + 0) % SYN_HIST_SIZE] +
                    history[(count + 1) % SYN_HIST_SIZE]) / 2;

                b = (value + history[(count + 0) % 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 + 1) % 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 dx, dy, edge;

        /*
         * Compute the next values of dx and dy
         */
        dx = synaptics_filter_policy(sc, sc->history_x, sp->sp_x);
        dy = synaptics_filter_policy(sc, sc->history_y, sp->sp_y);

        /*
         * 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);
        }

        /*
         * Apply scaling to both deltas
         */
        dx = synaptics_scale(dx, synaptics_scale_x, &sc->rem_x);
        dy = synaptics_scale(dy, synaptics_scale_y, &sc->rem_y);

        /*
         * Clamp deltas to specified maximums.
         */
        if (dx > synaptics_max_speed_x)
                dx = synaptics_max_speed_x;
        if (dy > synaptics_max_speed_y)
                dy = synaptics_max_speed_y;

        *dxp = dx;
        *dyp = dy;

        sc->movement_history++;
}

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;
        int fingers, palm, buttons, changed;
        int s;

        /*
         * 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) {
                                /*
                                 * Most up/down buttons will be actuated using
                                 * a rocker switch, so we should never see
                                 * them both simultaneously. But just in case,
                                 * treat this situation as a middle button
                                 * event.
                                 */
                                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_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;
        sc->total_packets++;

        /*
         * Do movement processing IFF we have a single finger and no palm.
         */
        if (fingers == 1 && palm == 0)
                synaptics_movement(sc, sp, &dx, &dy);
        else {
                /*
                 * No valid finger. Therefore no movement.
                 */
                sc->movement_history = 0;
                sc->rem_x = sc->rem_y = 0;
                dx = dy = 0;
        }

        /*
         * 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);
        }
}