/* $NetBSD: elantech.c,v 1.6 2014/02/25 18:30:10 pooka Exp $ */

/*-
 * Copyright (c) 2008 Jared D. McNeill <jmcneill@invisible.ca>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */

#include "opt_pms.h"

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: elantech.c,v 1.6 2014/02/25 18:30:10 pooka Exp $");

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

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

#include <dev/pckbport/pckbportvar.h>
#include <dev/pckbport/elantechreg.h>
#include <dev/pckbport/elantechvar.h>
#include <dev/pckbport/pmsreg.h>
#include <dev/pckbport/pmsvar.h>

/* #define ELANTECH_DEBUG */

static int elantech_xy_unprecision_nodenum;
static int elantech_z_unprecision_nodenum;

static int elantech_xy_unprecision = 2;
static int elantech_z_unprecision = 3;

struct elantech_packet {
        int16_t         ep_x, ep_y, ep_z;
        int8_t          ep_buttons;
        uint8_t         ep_nfingers;
};

static int
pms_sysctl_elantech_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;

        if (node.sysctl_num == elantech_xy_unprecision_nodenum ||
            node.sysctl_num == elantech_z_unprecision_nodenum) {
                if (t < 0 || t > 7)
                        return EINVAL;
        } else
                return EINVAL;

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

        return 0;
}

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

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT, CTLTYPE_NODE, "elantech",
            SYSCTL_DESCR("Elantech 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, "xy_precision_shift",
            SYSCTL_DESCR("X/Y-axis precision shift value"),
            pms_sysctl_elantech_verify, 0,
            &elantech_xy_unprecision,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        elantech_xy_unprecision_nodenum = node->sysctl_num;

        if ((rc = sysctl_createv(clog, 0, NULL, &node,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
            CTLTYPE_INT, "z_precision_shift",
            SYSCTL_DESCR("Z-axis precision shift value"),
            pms_sysctl_elantech_verify, 0,
            &elantech_z_unprecision,
            0, CTL_HW, root_num, CTL_CREATE,
            CTL_EOL)) != 0)
                goto err;

        elantech_z_unprecision_nodenum = node->sysctl_num;
        return;

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

static int
pms_elantech_read_1(pckbport_tag_t tag, pckbport_slot_t slot, uint8_t reg,
    uint8_t *val)
{
        int res;
        uint8_t cmd;
        uint8_t resp[3];

        cmd = ELANTECH_CUSTOM_CMD;
        res = pckbport_poll_cmd(tag, slot, &cmd, 1, 0, NULL, 0);
        cmd = ELANTECH_REG_READ;
        res |= pckbport_poll_cmd(tag, slot, &cmd, 1, 0, NULL, 0);
        cmd = ELANTECH_CUSTOM_CMD;
        res |= pckbport_poll_cmd(tag, slot, &cmd, 1, 0, NULL, 0);
        cmd = reg;
        res |= pckbport_poll_cmd(tag, slot, &cmd, 1, 0, NULL, 0);
        cmd = PMS_SEND_DEV_STATUS;
        res |= pckbport_poll_cmd(tag, slot, &cmd, 1, 3, resp, 0);

        if (res == 0)
                *val = resp[0];

        return res;
}

static int
pms_elantech_write_1(pckbport_tag_t tag, pckbport_slot_t slot, uint8_t reg,
    uint8_t val)
{
        int res;
        uint8_t cmd;

        cmd = ELANTECH_CUSTOM_CMD;
        res = pckbport_poll_cmd(tag, slot, &cmd, 1, 0, NULL, 0);
        cmd = ELANTECH_REG_WRITE;
        res |= pckbport_poll_cmd(tag, slot, &cmd, 1, 0, NULL, 0);
        cmd = ELANTECH_CUSTOM_CMD;
        res |= pckbport_poll_cmd(tag, slot, &cmd, 1, 0, NULL, 0);
        cmd = reg;
        res |= pckbport_poll_cmd(tag, slot, &cmd, 1, 0, NULL, 0);
        cmd = ELANTECH_CUSTOM_CMD;
        res |= pckbport_poll_cmd(tag, slot, &cmd, 1, 0, NULL, 0);
        cmd = val;
        res |= pckbport_poll_cmd(tag, slot, &cmd, 1, 0, NULL, 0);
        cmd = PMS_SET_SCALE11;
        res |= pckbport_poll_cmd(tag, slot, &cmd, 1, 0, NULL, 0);

        return res;
}

static int
pms_elantech_init(struct pms_softc *psc)
{
        uint8_t val;
        int res;

        /* set absolute mode */
        res = pms_elantech_write_1(psc->sc_kbctag, psc->sc_kbcslot, 0x10, 0x54);
        if (res)
                return res;
        res = pms_elantech_write_1(psc->sc_kbctag, psc->sc_kbcslot, 0x11, 0x88);
        if (res)
                return res;
        res = pms_elantech_write_1(psc->sc_kbctag, psc->sc_kbcslot, 0x21, 0x60);
        if (res)
                return res;

        res = pms_elantech_read_1(psc->sc_kbctag, psc->sc_kbcslot, 0x10, &val);

        if (res)
                aprint_error_dev(psc->sc_dev, "couldn't set absolute mode\n");

        return res;
}

static void
pms_elantech_input(void *opaque, int data)
{
        struct pms_softc *psc = opaque;
        struct elantech_softc *sc = &psc->u.elantech;
        struct elantech_packet ep;
        int s;

        if (!psc->sc_enabled)
                return;

        if (sc->version >= 0x020800) {
                if ((psc->inputstate == 0 && (data & 0x0c) != 0x04) ||
                    (psc->inputstate == 3 && (data & 0x0f) != 0x02)) {
                        aprint_debug_dev(psc->sc_dev, "waiting for sync..\n");
                        psc->inputstate = 0;
                        return;
                }
        } else {
                if ((psc->inputstate == 0 && (data & 0x0c) != 0x0c) ||
                    (psc->inputstate == 3 && (data & 0x0e) != 0x08)) {
                        aprint_debug_dev(psc->sc_dev, "waiting for sync..\n");
                        psc->inputstate = 0;
                        return;
                }
        }

        psc->packet[psc->inputstate++] = data & 0xff;
        if (psc->inputstate != 6)
                return;

        psc->inputstate = 0;

        ep.ep_nfingers = (psc->packet[0] & 0xc0) >> 6;
        ep.ep_buttons = 0;
        ep.ep_buttons = psc->packet[0] & 1;             /* left button */
        ep.ep_buttons |= (psc->packet[0] & 2) << 1;     /* right button */

        if (ep.ep_nfingers == 0 || ep.ep_nfingers != sc->last_nfingers)
                sc->initializing = true;

        switch (ep.ep_nfingers) {
        case 0:
                /* FALLTHROUGH */
        case 1:
                ep.ep_x = ((int16_t)(psc->packet[1] & 0xf) << 8) | psc->packet[2];
                ep.ep_y = ((int16_t)(psc->packet[4] & 0xf) << 8) | psc->packet[5];

                aprint_debug_dev(psc->sc_dev,
                    "%d finger detected in elantech mode:\n", ep.ep_nfingers);
                aprint_debug_dev(psc->sc_dev,
                    "  X=%d Y=%d\n", ep.ep_x, ep.ep_y);
                aprint_debug_dev(psc->sc_dev,
                    "  %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]);

                s = spltty();
                wsmouse_input(psc->sc_wsmousedev, ep.ep_buttons,
                    sc->initializing ?
                      0 : (ep.ep_x - sc->last_x) >> elantech_xy_unprecision,
                    sc->initializing ?
                      0 : (ep.ep_y - sc->last_y) >> elantech_xy_unprecision,
                    0, 0,
                    WSMOUSE_INPUT_DELTA);
                splx(s);

                if (sc->initializing == true ||
                    ((ep.ep_x - sc->last_x) >> elantech_xy_unprecision) != 0)
                        sc->last_x = ep.ep_x;
                if (sc->initializing == true ||
                    ((ep.ep_y - sc->last_y) >> elantech_xy_unprecision) != 0)
                        sc->last_y = ep.ep_y;
                break;
        case 2:
                /* emulate z axis */
                ep.ep_z = psc->packet[2];
                aprint_debug_dev(psc->sc_dev,
                    "2 fingers detected in elantech mode:\n");
                aprint_debug_dev(psc->sc_dev,
                    "  %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]);

                s = spltty();
                wsmouse_input(psc->sc_wsmousedev, 0,
                    0, 0,
                    sc->initializing ?
                      0 : (sc->last_z - ep.ep_z) >> elantech_z_unprecision,
                    0,
                    WSMOUSE_INPUT_DELTA);
                splx(s);

                if (sc->initializing == true ||
                    ((sc->last_z - ep.ep_z) >> elantech_z_unprecision) != 0)
                        sc->last_z = ep.ep_z;
                break;
        default:
                aprint_debug_dev(psc->sc_dev, "that's a lot of fingers!\n");
                return;
        }

        if (ep.ep_nfingers > 0)
                sc->initializing = false;
        sc->last_nfingers = ep.ep_nfingers;
}

int
pms_elantech_probe_init(void *opaque)
{
        struct pms_softc *psc = opaque;
        struct elantech_softc *sc = &psc->u.elantech;
        struct sysctllog *clog = NULL;
        u_char cmd[1], resp[3];
        uint16_t fwversion;
        int res;

        pckbport_flush(psc->sc_kbctag, psc->sc_kbcslot);

        cmd[0] = PMS_SET_SCALE11;
        if ((res = pckbport_poll_cmd(psc->sc_kbctag, psc->sc_kbcslot,
            cmd, 1, 0, NULL, 0)) != 0)
                goto doreset;
        cmd[0] = PMS_SET_SCALE11;
        if ((res = pckbport_poll_cmd(psc->sc_kbctag, psc->sc_kbcslot,
            cmd, 1, 0, NULL, 0)) != 0)
                goto doreset;
        cmd[0] = PMS_SET_SCALE11;
        if ((res = pckbport_poll_cmd(psc->sc_kbctag, psc->sc_kbcslot,
            cmd, 1, 0, NULL, 0)) != 0)
                goto doreset;

        cmd[0] = PMS_SEND_DEV_STATUS;
        if ((res = pckbport_poll_cmd(psc->sc_kbctag, psc->sc_kbcslot,
            cmd, 1, 3, resp, 0)) != 0)
                goto doreset;

        if (!ELANTECH_MAGIC(resp)) {
#ifdef ELANTECH_DEBUG
                aprint_error_dev(psc->sc_dev,
                    "bad elantech magic (%X %X %X)\n",
                    resp[0], resp[1], resp[2]);
#endif
                res = 1;
                goto doreset;
        }

        res = pms_sliced_command(psc->sc_kbctag, psc->sc_kbcslot,
            ELANTECH_FW_VERSION);
        cmd[0] = PMS_SEND_DEV_STATUS;
        res |= pckbport_poll_cmd(psc->sc_kbctag, psc->sc_kbcslot,
            cmd, 1, 3, resp, 0);
        if (res) {
                aprint_error_dev(psc->sc_dev,
                    "unable to query elantech firmware version\n");
                goto doreset;
        }

        fwversion = (resp[0] << 8) | resp[2];
        if (fwversion < ELANTECH_MIN_VERSION) {
                aprint_error_dev(psc->sc_dev,
                    "unsupported Elantech version %d.%d (%X %X %X)\n",
                    resp[0], resp[2], resp[0], resp[1], resp[2]);
                goto doreset;
        }
        sc->version = (resp[0] << 16) | (resp[1] << 8) | resp[2];
        aprint_normal_dev(psc->sc_dev, "Elantech touchpad version %d.%d (%06x)\n",
            resp[0], resp[2], sc->version);

        res = pms_elantech_init(psc);
        if (res) {
                aprint_error_dev(psc->sc_dev,
                    "couldn't initialize elantech touchpad\n");
                goto doreset;
        }

        pms_sysctl_elantech(&clog);
        pckbport_set_inputhandler(psc->sc_kbctag, psc->sc_kbcslot,
            pms_elantech_input, psc, device_xname(psc->sc_dev));

        return 0;

doreset:
        cmd[0] = PMS_RESET;
        (void)pckbport_poll_cmd(psc->sc_kbctag, psc->sc_kbcslot, cmd,
            1, 2, resp, 1);
        return res;
}

void
pms_elantech_enable(void *opaque)
{
        struct pms_softc *psc = opaque;
        struct elantech_softc *sc = &psc->u.elantech;

        sc->initializing = true;
}

void
pms_elantech_resume(void *opaque)
{
        struct pms_softc *psc = opaque;
        uint8_t cmd, resp[2];
        int res;

        cmd = PMS_RESET;
        res = pckbport_poll_cmd(psc->sc_kbctag, psc->sc_kbcslot, &cmd,
            1, 2, resp, 1);
        if (res)
                aprint_error_dev(psc->sc_dev,
                    "elantech reset on resume failed\n");
        else {
                pms_elantech_init(psc);
                pms_elantech_enable(psc);
        }
}