Input: synaptics - remove TOPBUTTONPAD property for Lenovos 2015

[mirror_ubuntu-artful-kernel.git] / drivers / input / mouse / synaptics.c

/*
 * Synaptics TouchPad PS/2 mouse driver
 *
 *   2003 Dmitry Torokhov <dtor@mail.ru>
 *     Added support for pass-through port. Special thanks to Peter Berg Larsen
 *     for explaining various Synaptics quirks.
 *
 *   2003 Peter Osterlund <petero2@telia.com>
 *     Ported to 2.5 input device infrastructure.
 *
 *   Copyright (C) 2001 Stefan Gmeiner <riddlebox@freesurf.ch>
 *     start merging tpconfig and gpm code to a xfree-input module
 *     adding some changes and extensions (ex. 3rd and 4th button)
 *
 *   Copyright (c) 1997 C. Scott Ananian <cananian@alumni.priceton.edu>
 *   Copyright (c) 1998-2000 Bruce Kalk <kall@compass.com>
 *     code for the special synaptics commands (from the tpconfig-source)
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 *
 * Trademarks are the property of their respective owners.
 */

#include <linux/module.h>
#include <linux/delay.h>
#include <linux/dmi.h>
#include <linux/input/mt.h>
#include <linux/serio.h>
#include <linux/libps2.h>
#include <linux/slab.h>
#include "psmouse.h"
#include "synaptics.h"

/*
 * The x/y limits are taken from the Synaptics TouchPad interfacing Guide,
 * section 2.3.2, which says that they should be valid regardless of the
 * actual size of the sensor.
 * Note that newer firmware allows querying device for maximum useable
 * coordinates.
 */
#define XMIN 0
#define XMAX 6143
#define YMIN 0
#define YMAX 6143
#define XMIN_NOMINAL 1472
#define XMAX_NOMINAL 5472
#define YMIN_NOMINAL 1408
#define YMAX_NOMINAL 4448

/* Size in bits of absolute position values reported by the hardware */
#define ABS_POS_BITS 13

/*
 * These values should represent the absolute maximum value that will
 * be reported for a positive position value. Some Synaptics firmware
 * uses this value to indicate a finger near the edge of the touchpad
 * whose precise position cannot be determined.
 *
 * At least one touchpad is known to report positions in excess of this
 * value which are actually negative values truncated to the 13-bit
 * reporting range. These values have never been observed to be lower
 * than 8184 (i.e. -8), so we treat all values greater than 8176 as
 * negative and any other value as positive.
 */
#define X_MAX_POSITIVE 8176
#define Y_MAX_POSITIVE 8176

/*****************************************************************************
 *      Stuff we need even when we do not want native Synaptics support
 ****************************************************************************/

/*
 * Set the synaptics touchpad mode byte by special commands
 */
static int synaptics_mode_cmd(struct psmouse *psmouse, unsigned char mode)
{
        unsigned char param[1];

        if (psmouse_sliced_command(psmouse, mode))
                return -1;
        param[0] = SYN_PS_SET_MODE2;
        if (ps2_command(&psmouse->ps2dev, param, PSMOUSE_CMD_SETRATE))
                return -1;
        return 0;
}

int synaptics_detect(struct psmouse *psmouse, bool set_properties)
{
        struct ps2dev *ps2dev = &psmouse->ps2dev;
        unsigned char param[4];

        param[0] = 0;

        ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES);
        ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES);
        ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES);
        ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES);
        ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO);

        if (param[1] != 0x47)
                return -ENODEV;

        if (set_properties) {
                psmouse->vendor = "Synaptics";
                psmouse->name = "TouchPad";
        }

        return 0;
}

void synaptics_reset(struct psmouse *psmouse)
{
        /* reset touchpad back to relative mode, gestures enabled */
        synaptics_mode_cmd(psmouse, 0);
}

#ifdef CONFIG_MOUSE_PS2_SYNAPTICS

static bool cr48_profile_sensor;

#define ANY_BOARD_ID 0
struct min_max_quirk {
        const char * const *pnp_ids;
        struct {
                unsigned long int min, max;
        } board_id;
        int x_min, x_max, y_min, y_max;
};

static const struct min_max_quirk min_max_pnpid_table[] = {
        {
                (const char * const []){"LEN0033", NULL},
                {ANY_BOARD_ID, ANY_BOARD_ID},
                1024, 5052, 2258, 4832
        },
        {
                (const char * const []){"LEN0042", NULL},
                {ANY_BOARD_ID, ANY_BOARD_ID},
                1232, 5710, 1156, 4696
        },
        {
                (const char * const []){"LEN0034", "LEN0036", "LEN0037",
                                        "LEN0039", "LEN2002", "LEN2004",
                                        NULL},
                {ANY_BOARD_ID, 2961},
                1024, 5112, 2024, 4832
        },
        {
                (const char * const []){"LEN2001", NULL},
                {ANY_BOARD_ID, ANY_BOARD_ID},
                1024, 5022, 2508, 4832
        },
        {
                (const char * const []){"LEN2006", NULL},
                {ANY_BOARD_ID, ANY_BOARD_ID},
                1264, 5675, 1171, 4688
        },
        { }
};

/* This list has been kindly provided by Synaptics. */
static const char * const topbuttonpad_pnp_ids[] = {
        "LEN0017",
        "LEN0018",
        "LEN0019",
        "LEN0023",
        "LEN002A",
        "LEN002B",
        "LEN002C",
        "LEN002D",
        "LEN002E",
        "LEN0033", /* Helix */
        "LEN0034", /* T431s, L440, L540, T540, W540, X1 Carbon 2nd */
        "LEN0035", /* X240 */
        "LEN0036", /* T440 */
        "LEN0037", /* X1 Carbon 2nd */
        "LEN0038",
        "LEN0039", /* T440s */
        "LEN0041",
        "LEN0042", /* Yoga */
        "LEN0045",
        "LEN0046",
        "LEN0047",
        "LEN0048",
        "LEN0049",
        "LEN2000",
        "LEN2001", /* Edge E431 */
        "LEN2002", /* Edge E531 */
        "LEN2003",
        "LEN2004", /* L440 */
        "LEN2005",
        "LEN2006",
        "LEN2007",
        "LEN2008",
        "LEN2009",
        "LEN200A",
        "LEN200B",
        NULL
};

/*****************************************************************************
 *      Synaptics communications functions
 ****************************************************************************/

/*
 * Synaptics touchpads report the y coordinate from bottom to top, which is
 * opposite from what userspace expects.
 * This function is used to invert y before reporting.
 */
static int synaptics_invert_y(int y)
{
        return YMAX_NOMINAL + YMIN_NOMINAL - y;
}

/*
 * Send a command to the synpatics touchpad by special commands
 */
static int synaptics_send_cmd(struct psmouse *psmouse, unsigned char c, unsigned char *param)
{
        if (psmouse_sliced_command(psmouse, c))
                return -1;
        if (ps2_command(&psmouse->ps2dev, param, PSMOUSE_CMD_GETINFO))
                return -1;
        return 0;
}

/*
 * Read the model-id bytes from the touchpad
 * see also SYN_MODEL_* macros
 */
static int synaptics_model_id(struct psmouse *psmouse)
{
        struct synaptics_data *priv = psmouse->private;
        unsigned char mi[3];

        if (synaptics_send_cmd(psmouse, SYN_QUE_MODEL, mi))
                return -1;
        priv->model_id = (mi[0]<<16) | (mi[1]<<8) | mi[2];
        return 0;
}

static int synaptics_more_extended_queries(struct psmouse *psmouse)
{
        struct synaptics_data *priv = psmouse->private;
        unsigned char buf[3];

        if (synaptics_send_cmd(psmouse, SYN_QUE_MEXT_CAPAB_10, buf))
                return -1;

        priv->ext_cap_10 = (buf[0]<<16) | (buf[1]<<8) | buf[2];

        return 0;
}

/*
 * Read the board id and the "More Extended Queries" from the touchpad
 * The board id is encoded in the "QUERY MODES" response
 */
static int synaptics_query_modes(struct psmouse *psmouse)
{
        struct synaptics_data *priv = psmouse->private;
        unsigned char bid[3];

        /* firmwares prior 7.5 have no board_id encoded */
        if (SYN_ID_FULL(priv->identity) < 0x705)
                return 0;

        if (synaptics_send_cmd(psmouse, SYN_QUE_MODES, bid))
                return -1;
        priv->board_id = ((bid[0] & 0xfc) << 6) | bid[1];

        if (SYN_MEXT_CAP_BIT(bid[0]))
                return synaptics_more_extended_queries(psmouse);

        return 0;
}

/*
 * Read the firmware id from the touchpad
 */
static int synaptics_firmware_id(struct psmouse *psmouse)
{
        struct synaptics_data *priv = psmouse->private;
        unsigned char fwid[3];

        if (synaptics_send_cmd(psmouse, SYN_QUE_FIRMWARE_ID, fwid))
                return -1;
        priv->firmware_id = (fwid[0] << 16) | (fwid[1] << 8) | fwid[2];
        return 0;
}

/*
 * Read the capability-bits from the touchpad
 * see also the SYN_CAP_* macros
 */
static int synaptics_capability(struct psmouse *psmouse)
{
        struct synaptics_data *priv = psmouse->private;
        unsigned char cap[3];

        if (synaptics_send_cmd(psmouse, SYN_QUE_CAPABILITIES, cap))
                return -1;
        priv->capabilities = (cap[0] << 16) | (cap[1] << 8) | cap[2];
        priv->ext_cap = priv->ext_cap_0c = 0;

        /*
         * Older firmwares had submodel ID fixed to 0x47
         */
        if (SYN_ID_FULL(priv->identity) < 0x705 &&
            SYN_CAP_SUBMODEL_ID(priv->capabilities) != 0x47) {
                return -1;
        }

        /*
         * Unless capExtended is set the rest of the flags should be ignored
         */
        if (!SYN_CAP_EXTENDED(priv->capabilities))
                priv->capabilities = 0;

        if (SYN_EXT_CAP_REQUESTS(priv->capabilities) >= 1) {
                if (synaptics_send_cmd(psmouse, SYN_QUE_EXT_CAPAB, cap)) {
                        psmouse_warn(psmouse,
                                     "device claims to have extended capabilities, but I'm not able to read them.\n");
                } else {
                        priv->ext_cap = (cap[0] << 16) | (cap[1] << 8) | cap[2];

                        /*
                         * if nExtBtn is greater than 8 it should be considered
                         * invalid and treated as 0
                         */
                        if (SYN_CAP_MULTI_BUTTON_NO(priv->ext_cap) > 8)
                                priv->ext_cap &= 0xff0fff;
                }
        }

        if (SYN_EXT_CAP_REQUESTS(priv->capabilities) >= 4) {
                if (synaptics_send_cmd(psmouse, SYN_QUE_EXT_CAPAB_0C, cap)) {
                        psmouse_warn(psmouse,
                                     "device claims to have extended capability 0x0c, but I'm not able to read it.\n");
                } else {
                        priv->ext_cap_0c = (cap[0] << 16) | (cap[1] << 8) | cap[2];
                }
        }

        return 0;
}

/*
 * Identify Touchpad
 * See also the SYN_ID_* macros
 */
static int synaptics_identify(struct psmouse *psmouse)
{
        struct synaptics_data *priv = psmouse->private;
        unsigned char id[3];

        if (synaptics_send_cmd(psmouse, SYN_QUE_IDENTIFY, id))
                return -1;
        priv->identity = (id[0]<<16) | (id[1]<<8) | id[2];
        if (SYN_ID_IS_SYNAPTICS(priv->identity))
                return 0;
        return -1;
}

/*
 * Read touchpad resolution and maximum reported coordinates
 * Resolution is left zero if touchpad does not support the query
 */

static int synaptics_resolution(struct psmouse *psmouse)
{
        struct synaptics_data *priv = psmouse->private;
        unsigned char resp[3];

        if (SYN_ID_MAJOR(priv->identity) < 4)
                return 0;

        if (synaptics_send_cmd(psmouse, SYN_QUE_RESOLUTION, resp) == 0) {
                if (resp[0] != 0 && (resp[1] & 0x80) && resp[2] != 0) {
                        priv->x_res = resp[0]; /* x resolution in units/mm */
                        priv->y_res = resp[2]; /* y resolution in units/mm */
                }
        }

        if (SYN_EXT_CAP_REQUESTS(priv->capabilities) >= 5 &&
            SYN_CAP_MAX_DIMENSIONS(priv->ext_cap_0c)) {
                if (synaptics_send_cmd(psmouse, SYN_QUE_EXT_MAX_COORDS, resp)) {
                        psmouse_warn(psmouse,
                                     "device claims to have max coordinates query, but I'm not able to read it.\n");
                } else {
                        priv->x_max = (resp[0] << 5) | ((resp[1] & 0x0f) << 1);
                        priv->y_max = (resp[2] << 5) | ((resp[1] & 0xf0) >> 3);
                        psmouse_info(psmouse,
                                     "queried max coordinates: x [..%d], y [..%d]\n",
                                     priv->x_max, priv->y_max);
                }
        }

        if (SYN_CAP_MIN_DIMENSIONS(priv->ext_cap_0c) &&
            (SYN_EXT_CAP_REQUESTS(priv->capabilities) >= 7 ||
             /*
              * Firmware v8.1 does not report proper number of extended
              * capabilities, but has been proven to report correct min
              * coordinates.
              */
             SYN_ID_FULL(priv->identity) == 0x801)) {
                if (synaptics_send_cmd(psmouse, SYN_QUE_EXT_MIN_COORDS, resp)) {
                        psmouse_warn(psmouse,
                                     "device claims to have min coordinates query, but I'm not able to read it.\n");
                } else {
                        priv->x_min = (resp[0] << 5) | ((resp[1] & 0x0f) << 1);
                        priv->y_min = (resp[2] << 5) | ((resp[1] & 0xf0) >> 3);
                        psmouse_info(psmouse,
                                     "queried min coordinates: x [%d..], y [%d..]\n",
                                     priv->x_min, priv->y_min);
                }
        }

        return 0;
}

/*
 * Apply quirk(s) if the hardware matches
 */

static void synaptics_apply_quirks(struct psmouse *psmouse)
{
        struct synaptics_data *priv = psmouse->private;
        int i;

        for (i = 0; min_max_pnpid_table[i].pnp_ids; i++) {
                if (!psmouse_matches_pnp_id(psmouse,
                                            min_max_pnpid_table[i].pnp_ids))
                        continue;

                if (min_max_pnpid_table[i].board_id.min != ANY_BOARD_ID &&
                    priv->board_id < min_max_pnpid_table[i].board_id.min)
                        continue;

                if (min_max_pnpid_table[i].board_id.max != ANY_BOARD_ID &&
                    priv->board_id > min_max_pnpid_table[i].board_id.max)
                        continue;

                priv->x_min = min_max_pnpid_table[i].x_min;
                priv->x_max = min_max_pnpid_table[i].x_max;
                priv->y_min = min_max_pnpid_table[i].y_min;
                priv->y_max = min_max_pnpid_table[i].y_max;
                psmouse_info(psmouse,
                             "quirked min/max coordinates: x [%d..%d], y [%d..%d]\n",
                             priv->x_min, priv->x_max,
                             priv->y_min, priv->y_max);
                break;
        }
}

static int synaptics_query_hardware(struct psmouse *psmouse)
{
        if (synaptics_identify(psmouse))
                return -1;
        if (synaptics_model_id(psmouse))
                return -1;
        if (synaptics_firmware_id(psmouse))
                return -1;
        if (synaptics_query_modes(psmouse))
                return -1;
        if (synaptics_capability(psmouse))
                return -1;
        if (synaptics_resolution(psmouse))
                return -1;

        synaptics_apply_quirks(psmouse);

        return 0;
}

static int synaptics_set_advanced_gesture_mode(struct psmouse *psmouse)
{
        static unsigned char param = 0xc8;
        struct synaptics_data *priv = psmouse->private;

        if (!(SYN_CAP_ADV_GESTURE(priv->ext_cap_0c) ||
              SYN_CAP_IMAGE_SENSOR(priv->ext_cap_0c)))
                return 0;

        if (psmouse_sliced_command(psmouse, SYN_QUE_MODEL))
                return -1;

        if (ps2_command(&psmouse->ps2dev, &param, PSMOUSE_CMD_SETRATE))
                return -1;

        /* Advanced gesture mode also sends multi finger data */
        priv->capabilities |= BIT(1);

        return 0;
}

static int synaptics_set_mode(struct psmouse *psmouse)
{
        struct synaptics_data *priv = psmouse->private;

        priv->mode = 0;
        if (priv->absolute_mode)
                priv->mode |= SYN_BIT_ABSOLUTE_MODE;
        if (priv->disable_gesture)
                priv->mode |= SYN_BIT_DISABLE_GESTURE;
        if (psmouse->rate >= 80)
                priv->mode |= SYN_BIT_HIGH_RATE;
        if (SYN_CAP_EXTENDED(priv->capabilities))
                priv->mode |= SYN_BIT_W_MODE;

        if (synaptics_mode_cmd(psmouse, priv->mode))
                return -1;

        if (priv->absolute_mode &&
            synaptics_set_advanced_gesture_mode(psmouse)) {
                psmouse_err(psmouse, "Advanced gesture mode init failed.\n");
                return -1;
        }

        return 0;
}

static void synaptics_set_rate(struct psmouse *psmouse, unsigned int rate)
{
        struct synaptics_data *priv = psmouse->private;

        if (rate >= 80) {
                priv->mode |= SYN_BIT_HIGH_RATE;
                psmouse->rate = 80;
        } else {
                priv->mode &= ~SYN_BIT_HIGH_RATE;
                psmouse->rate = 40;
        }

        synaptics_mode_cmd(psmouse, priv->mode);
}

/*****************************************************************************
 *      Synaptics pass-through PS/2 port support
 ****************************************************************************/
static int synaptics_pt_write(struct serio *serio, unsigned char c)
{
        struct psmouse *parent = serio_get_drvdata(serio->parent);
        char rate_param = SYN_PS_CLIENT_CMD; /* indicates that we want pass-through port */

        if (psmouse_sliced_command(parent, c))
                return -1;
        if (ps2_command(&parent->ps2dev, &rate_param, PSMOUSE_CMD_SETRATE))
                return -1;
        return 0;
}

static int synaptics_pt_start(struct serio *serio)
{
        struct psmouse *parent = serio_get_drvdata(serio->parent);
        struct synaptics_data *priv = parent->private;

        serio_pause_rx(parent->ps2dev.serio);
        priv->pt_port = serio;
        serio_continue_rx(parent->ps2dev.serio);

        return 0;
}

static void synaptics_pt_stop(struct serio *serio)
{
        struct psmouse *parent = serio_get_drvdata(serio->parent);
        struct synaptics_data *priv = parent->private;

        serio_pause_rx(parent->ps2dev.serio);
        priv->pt_port = NULL;
        serio_continue_rx(parent->ps2dev.serio);
}

static int synaptics_is_pt_packet(unsigned char *buf)
{
        return (buf[0] & 0xFC) == 0x84 && (buf[3] & 0xCC) == 0xC4;
}

static void synaptics_pass_pt_packet(struct serio *ptport, unsigned char *packet)
{
        struct psmouse *child = serio_get_drvdata(ptport);

        if (child && child->state == PSMOUSE_ACTIVATED) {
                serio_interrupt(ptport, packet[1], 0);
                serio_interrupt(ptport, packet[4], 0);
                serio_interrupt(ptport, packet[5], 0);
                if (child->pktsize == 4)
                        serio_interrupt(ptport, packet[2], 0);
        } else
                serio_interrupt(ptport, packet[1], 0);
}

static void synaptics_pt_activate(struct psmouse *psmouse)
{
        struct synaptics_data *priv = psmouse->private;
        struct psmouse *child = serio_get_drvdata(priv->pt_port);

        /* adjust the touchpad to child's choice of protocol */
        if (child) {
                if (child->pktsize == 4)
                        priv->mode |= SYN_BIT_FOUR_BYTE_CLIENT;
                else
                        priv->mode &= ~SYN_BIT_FOUR_BYTE_CLIENT;

                if (synaptics_mode_cmd(psmouse, priv->mode))
                        psmouse_warn(psmouse,
                                     "failed to switch guest protocol\n");
        }
}

static void synaptics_pt_create(struct psmouse *psmouse)
{
        struct serio *serio;

        serio = kzalloc(sizeof(struct serio), GFP_KERNEL);
        if (!serio) {
                psmouse_err(psmouse,
                            "not enough memory for pass-through port\n");
                return;
        }

        serio->id.type = SERIO_PS_PSTHRU;
        strlcpy(serio->name, "Synaptics pass-through", sizeof(serio->name));
        strlcpy(serio->phys, "synaptics-pt/serio0", sizeof(serio->name));
        serio->write = synaptics_pt_write;
        serio->start = synaptics_pt_start;
        serio->stop = synaptics_pt_stop;
        serio->parent = psmouse->ps2dev.serio;

        psmouse->pt_activate = synaptics_pt_activate;

        psmouse_info(psmouse, "serio: %s port at %s\n",
                     serio->name, psmouse->phys);
        serio_register_port(serio);
}

/*****************************************************************************
 *      Functions to interpret the absolute mode packets
 ****************************************************************************/

static void synaptics_mt_state_set(struct synaptics_mt_state *state, int count,
                                   int sgm, int agm)
{
        state->count = count;
        state->sgm = sgm;
        state->agm = agm;
}

static void synaptics_parse_agm(const unsigned char buf[],
                                struct synaptics_data *priv,
                                struct synaptics_hw_state *hw)
{
        struct synaptics_hw_state *agm = &priv->agm;
        int agm_packet_type;

        agm_packet_type = (buf[5] & 0x30) >> 4;
        switch (agm_packet_type) {
        case 1:
                /* Gesture packet: (x, y, z) half resolution */
                agm->w = hw->w;
                agm->x = (((buf[4] & 0x0f) << 8) | buf[1]) << 1;
                agm->y = (((buf[4] & 0xf0) << 4) | buf[2]) << 1;
                agm->z = ((buf[3] & 0x30) | (buf[5] & 0x0f)) << 1;
                break;

        case 2:
                /* AGM-CONTACT packet: (count, sgm, agm) */
                synaptics_mt_state_set(&agm->mt_state, buf[1], buf[2], buf[4]);
                break;

        default:
                break;
        }

        /* Record that at least one AGM has been received since last SGM */
        priv->agm_pending = true;
}

static void synaptics_parse_ext_buttons(const unsigned char buf[],
                                        struct synaptics_data *priv,
                                        struct synaptics_hw_state *hw)
{
        unsigned int ext_bits =
                (SYN_CAP_MULTI_BUTTON_NO(priv->ext_cap) + 1) >> 1;
        unsigned int ext_mask = GENMASK(ext_bits - 1, 0);

        hw->ext_buttons = buf[4] & ext_mask;
        hw->ext_buttons |= (buf[5] & ext_mask) << ext_bits;
}

static bool is_forcepad;

static int synaptics_parse_hw_state(const unsigned char buf[],
                                    struct synaptics_data *priv,
                                    struct synaptics_hw_state *hw)
{
        memset(hw, 0, sizeof(struct synaptics_hw_state));

        if (SYN_MODEL_NEWABS(priv->model_id)) {
                hw->w = (((buf[0] & 0x30) >> 2) |
                         ((buf[0] & 0x04) >> 1) |
                         ((buf[3] & 0x04) >> 2));

                if ((SYN_CAP_ADV_GESTURE(priv->ext_cap_0c) ||
                        SYN_CAP_IMAGE_SENSOR(priv->ext_cap_0c)) &&
                    hw->w == 2) {
                        synaptics_parse_agm(buf, priv, hw);
                        return 1;
                }

                hw->x = (((buf[3] & 0x10) << 8) |
                         ((buf[1] & 0x0f) << 8) |
                         buf[4]);
                hw->y = (((buf[3] & 0x20) << 7) |
                         ((buf[1] & 0xf0) << 4) |
                         buf[5]);
                hw->z = buf[2];

                hw->left  = (buf[0] & 0x01) ? 1 : 0;
                hw->right = (buf[0] & 0x02) ? 1 : 0;

                if (is_forcepad) {
                        /*
                         * ForcePads, like Clickpads, use middle button
                         * bits to report primary button clicks.
                         * Unfortunately they report primary button not
                         * only when user presses on the pad above certain
                         * threshold, but also when there are more than one
                         * finger on the touchpad, which interferes with
                         * out multi-finger gestures.
                         */
                        if (hw->z == 0) {
                                /* No contacts */
                                priv->press = priv->report_press = false;
                        } else if (hw->w >= 4 && ((buf[0] ^ buf[3]) & 0x01)) {
                                /*
                                 * Single-finger touch with pressure above
                                 * the threshold. If pressure stays long
                                 * enough, we'll start reporting primary
                                 * button. We rely on the device continuing
                                 * sending data even if finger does not
                                 * move.
                                 */
                                if  (!priv->press) {
                                        priv->press_start = jiffies;
                                        priv->press = true;
                                } else if (time_after(jiffies,
                                                priv->press_start +
                                                        msecs_to_jiffies(50))) {
                                        priv->report_press = true;
                                }
                        } else {
                                priv->press = false;
                        }

                        hw->left = priv->report_press;

                } else if (SYN_CAP_CLICKPAD(priv->ext_cap_0c)) {
                        /*
                         * Clickpad's button is transmitted as middle button,
                         * however, since it is primary button, we will report
                         * it as BTN_LEFT.
                         */
                        hw->left = ((buf[0] ^ buf[3]) & 0x01) ? 1 : 0;

                } else if (SYN_CAP_MIDDLE_BUTTON(priv->capabilities)) {
                        hw->middle = ((buf[0] ^ buf[3]) & 0x01) ? 1 : 0;
                        if (hw->w == 2)
                                hw->scroll = (signed char)(buf[1]);
                }

                if (SYN_CAP_FOUR_BUTTON(priv->capabilities)) {
                        hw->up   = ((buf[0] ^ buf[3]) & 0x01) ? 1 : 0;
                        hw->down = ((buf[0] ^ buf[3]) & 0x02) ? 1 : 0;
                }

                if (SYN_CAP_MULTI_BUTTON_NO(priv->ext_cap) > 0 &&
                    ((buf[0] ^ buf[3]) & 0x02)) {
                        synaptics_parse_ext_buttons(buf, priv, hw);
                }
        } else {
                hw->x = (((buf[1] & 0x1f) << 8) | buf[2]);
                hw->y = (((buf[4] & 0x1f) << 8) | buf[5]);

                hw->z = (((buf[0] & 0x30) << 2) | (buf[3] & 0x3F));
                hw->w = (((buf[1] & 0x80) >> 4) | ((buf[0] & 0x04) >> 1));

                hw->left  = (buf[0] & 0x01) ? 1 : 0;
                hw->right = (buf[0] & 0x02) ? 1 : 0;
        }

        /*
         * Convert wrap-around values to negative. (X|Y)_MAX_POSITIVE
         * is used by some firmware to indicate a finger at the edge of
         * the touchpad whose precise position cannot be determined, so
         * convert these values to the maximum axis value.
         */
        if (hw->x > X_MAX_POSITIVE)
                hw->x -= 1 << ABS_POS_BITS;
        else if (hw->x == X_MAX_POSITIVE)
                hw->x = XMAX;

        if (hw->y > Y_MAX_POSITIVE)
                hw->y -= 1 << ABS_POS_BITS;
        else if (hw->y == Y_MAX_POSITIVE)
                hw->y = YMAX;

        return 0;
}

static void synaptics_report_semi_mt_slot(struct input_dev *dev, int slot,
                                          bool active, int x, int y)
{
        input_mt_slot(dev, slot);
        input_mt_report_slot_state(dev, MT_TOOL_FINGER, active);
        if (active) {
                input_report_abs(dev, ABS_MT_POSITION_X, x);
                input_report_abs(dev, ABS_MT_POSITION_Y, synaptics_invert_y(y));
        }
}

static void synaptics_report_semi_mt_data(struct input_dev *dev,
                                          const struct synaptics_hw_state *a,
                                          const struct synaptics_hw_state *b,
                                          int num_fingers)
{
        if (num_fingers >= 2) {
                synaptics_report_semi_mt_slot(dev, 0, true, min(a->x, b->x),
                                              min(a->y, b->y));
                synaptics_report_semi_mt_slot(dev, 1, true, max(a->x, b->x),
                                              max(a->y, b->y));
        } else if (num_fingers == 1) {
                synaptics_report_semi_mt_slot(dev, 0, true, a->x, a->y);
                synaptics_report_semi_mt_slot(dev, 1, false, 0, 0);
        } else {
                synaptics_report_semi_mt_slot(dev, 0, false, 0, 0);
                synaptics_report_semi_mt_slot(dev, 1, false, 0, 0);
        }
}

static void synaptics_report_ext_buttons(struct psmouse *psmouse,
                                         const struct synaptics_hw_state *hw)
{
        struct input_dev *dev = psmouse->dev;
        struct synaptics_data *priv = psmouse->private;
        int ext_bits = (SYN_CAP_MULTI_BUTTON_NO(priv->ext_cap) + 1) >> 1;
        int i;

        if (!SYN_CAP_MULTI_BUTTON_NO(priv->ext_cap))
                return;

        /* Bug in FW 8.1, buttons are reported only when ExtBit is 1 */
        if (SYN_ID_FULL(priv->identity) == 0x801 &&
            !((psmouse->packet[0] ^ psmouse->packet[3]) & 0x02))
                return;

        for (i = 0; i < ext_bits; i++) {
                input_report_key(dev, BTN_0 + 2 * i,
                        hw->ext_buttons & (1 << i));
                input_report_key(dev, BTN_1 + 2 * i,
                        hw->ext_buttons & (1 << (i + ext_bits)));
        }
}

static void synaptics_report_buttons(struct psmouse *psmouse,
                                     const struct synaptics_hw_state *hw)
{
        struct input_dev *dev = psmouse->dev;
        struct synaptics_data *priv = psmouse->private;

        input_report_key(dev, BTN_LEFT, hw->left);
        input_report_key(dev, BTN_RIGHT, hw->right);

        if (SYN_CAP_MIDDLE_BUTTON(priv->capabilities))
                input_report_key(dev, BTN_MIDDLE, hw->middle);

        if (SYN_CAP_FOUR_BUTTON(priv->capabilities)) {
                input_report_key(dev, BTN_FORWARD, hw->up);
                input_report_key(dev, BTN_BACK, hw->down);
        }

        synaptics_report_ext_buttons(psmouse, hw);
}

static void synaptics_report_slot(struct input_dev *dev, int slot,
                                  const struct synaptics_hw_state *hw)
{
        input_mt_slot(dev, slot);
        input_mt_report_slot_state(dev, MT_TOOL_FINGER, (hw != NULL));
        if (!hw)
                return;

        input_report_abs(dev, ABS_MT_POSITION_X, hw->x);
        input_report_abs(dev, ABS_MT_POSITION_Y, synaptics_invert_y(hw->y));
        input_report_abs(dev, ABS_MT_PRESSURE, hw->z);
}

static void synaptics_report_mt_data(struct psmouse *psmouse,
                                     struct synaptics_mt_state *mt_state,
                                     const struct synaptics_hw_state *sgm)
{
        struct input_dev *dev = psmouse->dev;
        struct synaptics_data *priv = psmouse->private;
        struct synaptics_hw_state *agm = &priv->agm;
        struct synaptics_mt_state *old = &priv->mt_state;

        switch (mt_state->count) {
        case 0:
                synaptics_report_slot(dev, 0, NULL);
                synaptics_report_slot(dev, 1, NULL);
                break;
        case 1:
                if (mt_state->sgm == -1) {
                        synaptics_report_slot(dev, 0, NULL);
                        synaptics_report_slot(dev, 1, NULL);
                } else if (mt_state->sgm == 0) {
                        synaptics_report_slot(dev, 0, sgm);
                        synaptics_report_slot(dev, 1, NULL);
                } else {
                        synaptics_report_slot(dev, 0, NULL);
                        synaptics_report_slot(dev, 1, sgm);
                }
                break;
        default:
                /*
                 * If the finger slot contained in SGM is valid, and either
                 * hasn't changed, or is new, or the old SGM has now moved to
                 * AGM, then report SGM in MTB slot 0.
                 * Otherwise, empty MTB slot 0.
                 */
                if (mt_state->sgm != -1 &&
                    (mt_state->sgm == old->sgm ||
                     old->sgm == -1 || mt_state->agm == old->sgm))
                        synaptics_report_slot(dev, 0, sgm);
                else
                        synaptics_report_slot(dev, 0, NULL);

                /*
                 * If the finger slot contained in AGM is valid, and either
                 * hasn't changed, or is new, then report AGM in MTB slot 1.
                 * Otherwise, empty MTB slot 1.
                 *
                 * However, in the case where the AGM is new, make sure that
                 * that it is either the same as the old SGM, or there was no
                 * SGM.
                 *
                 * Otherwise, if the SGM was just 1, and the new AGM is 2, then
                 * the new AGM will keep the old SGM's tracking ID, which can
                 * cause apparent drumroll.  This happens if in the following
                 * valid finger sequence:
                 *
                 *  Action                 SGM  AGM (MTB slot:Contact)
                 *  1. Touch contact 0    (0:0)
                 *  2. Touch contact 1    (0:0, 1:1)
                 *  3. Lift  contact 0    (1:1)
                 *  4. Touch contacts 2,3 (0:2, 1:3)
                 *
                 * In step 4, contact 3, in AGM must not be given the same
                 * tracking ID as contact 1 had in step 3.  To avoid this,
                 * the first agm with contact 3 is dropped and slot 1 is
                 * invalidated (tracking ID = -1).
                 */
                if (mt_state->agm != -1 &&
                    (mt_state->agm == old->agm ||
                     (old->agm == -1 &&
                      (old->sgm == -1 || mt_state->agm == old->sgm))))
                        synaptics_report_slot(dev, 1, agm);
                else
                        synaptics_report_slot(dev, 1, NULL);
                break;
        }

        /* Don't use active slot count to generate BTN_TOOL events. */
        input_mt_report_pointer_emulation(dev, false);

        /* Send the number of fingers reported by touchpad itself. */
        input_mt_report_finger_count(dev, mt_state->count);

        synaptics_report_buttons(psmouse, sgm);

        input_sync(dev);
}

/* Handle case where mt_state->count = 0 */
static void synaptics_image_sensor_0f(struct synaptics_data *priv,
                                      struct synaptics_mt_state *mt_state)
{
        synaptics_mt_state_set(mt_state, 0, -1, -1);
        priv->mt_state_lost = false;
}

/* Handle case where mt_state->count = 1 */
static void synaptics_image_sensor_1f(struct synaptics_data *priv,
                                      struct synaptics_mt_state *mt_state)
{
        struct synaptics_hw_state *agm = &priv->agm;
        struct synaptics_mt_state *old = &priv->mt_state;

        /*
         * If the last AGM was (0,0,0), and there is only one finger left,
         * then we absolutely know that SGM contains slot 0, and all other
         * fingers have been removed.
         */
        if (priv->agm_pending && agm->z == 0) {
                synaptics_mt_state_set(mt_state, 1, 0, -1);
                priv->mt_state_lost = false;
                return;
        }

        switch (old->count) {
        case 0:
                synaptics_mt_state_set(mt_state, 1, 0, -1);
                break;
        case 1:
                /*
                 * If mt_state_lost, then the previous transition was 3->1,
                 * and SGM now contains either slot 0 or 1, but we don't know
                 * which.  So, we just assume that the SGM now contains slot 1.
                 *
                 * If pending AGM and either:
                 *   (a) the previous SGM slot contains slot 0, or
                 *   (b) there was no SGM slot
                 * then, the SGM now contains slot 1
                 *
                 * Case (a) happens with very rapid "drum roll" gestures, where
                 * slot 0 finger is lifted and a new slot 1 finger touches
                 * within one reporting interval.
                 *
                 * Case (b) happens if initially two or more fingers tap
                 * briefly, and all but one lift before the end of the first
                 * reporting interval.
                 *
                 * (In both these cases, slot 0 will becomes empty, so SGM
                 * contains slot 1 with the new finger)
                 *
                 * Else, if there was no previous SGM, it now contains slot 0.
                 *
                 * Otherwise, SGM still contains the same slot.
                 */
                if (priv->mt_state_lost ||
                    (priv->agm_pending && old->sgm <= 0))
                        synaptics_mt_state_set(mt_state, 1, 1, -1);
                else if (old->sgm == -1)
                        synaptics_mt_state_set(mt_state, 1, 0, -1);
                break;
        case 2:
                /*
                 * If mt_state_lost, we don't know which finger SGM contains.
                 *
                 * So, report 1 finger, but with both slots empty.
                 * We will use slot 1 on subsequent 1->1
                 */
                if (priv->mt_state_lost) {
                        synaptics_mt_state_set(mt_state, 1, -1, -1);
                        break;
                }
                /*
                 * Since the last AGM was NOT (0,0,0), it was the finger in
                 * slot 0 that has been removed.
                 * So, SGM now contains previous AGM's slot, and AGM is now
                 * empty.
                 */
                synaptics_mt_state_set(mt_state, 1, old->agm, -1);
                break;
        case 3:
                /*
                 * Since last AGM was not (0,0,0), we don't know which finger
                 * is left.
                 *
                 * So, report 1 finger, but with both slots empty.
                 * We will use slot 1 on subsequent 1->1
                 */
                synaptics_mt_state_set(mt_state, 1, -1, -1);
                priv->mt_state_lost = true;
                break;
        case 4:
        case 5:
                /* mt_state was updated by AGM-CONTACT packet */
                break;
        }
}

/* Handle case where mt_state->count = 2 */
static void synaptics_image_sensor_2f(struct synaptics_data *priv,
                                      struct synaptics_mt_state *mt_state)
{
        struct synaptics_mt_state *old = &priv->mt_state;

        switch (old->count) {
        case 0:
                synaptics_mt_state_set(mt_state, 2, 0, 1);
                break;
        case 1:
                /*
                 * If previous SGM contained slot 1 or higher, SGM now contains
                 * slot 0 (the newly touching finger) and AGM contains SGM's
                 * previous slot.
                 *
                 * Otherwise, SGM still contains slot 0 and AGM now contains
                 * slot 1.
                 */
                if (old->sgm >= 1)
                        synaptics_mt_state_set(mt_state, 2, 0, old->sgm);
                else
                        synaptics_mt_state_set(mt_state, 2, 0, 1);
                break;
        case 2:
                /*
                 * If mt_state_lost, SGM now contains either finger 1 or 2, but
                 * we don't know which.
                 * So, we just assume that the SGM contains slot 0 and AGM 1.
                 */
                if (priv->mt_state_lost)
                        synaptics_mt_state_set(mt_state, 2, 0, 1);
                /*
                 * Otherwise, use the same mt_state, since it either hasn't
                 * changed, or was updated by a recently received AGM-CONTACT
                 * packet.
                 */
                break;
        case 3:
                /*
                 * 3->2 transitions have two unsolvable problems:
                 *  1) no indication is given which finger was removed
                 *  2) no way to tell if agm packet was for finger 3
                 *     before 3->2, or finger 2 after 3->2.
                 *
                 * So, report 2 fingers, but empty all slots.
                 * We will guess slots [0,1] on subsequent 2->2.
                 */
                synaptics_mt_state_set(mt_state, 2, -1, -1);
                priv->mt_state_lost = true;
                break;
        case 4:
        case 5:
                /* mt_state was updated by AGM-CONTACT packet */
                break;
        }
}

/* Handle case where mt_state->count = 3 */
static void synaptics_image_sensor_3f(struct synaptics_data *priv,
                                      struct synaptics_mt_state *mt_state)
{
        struct synaptics_mt_state *old = &priv->mt_state;

        switch (old->count) {
        case 0:
                synaptics_mt_state_set(mt_state, 3, 0, 2);
                break;
        case 1:
                /*
                 * If previous SGM contained slot 2 or higher, SGM now contains
                 * slot 0 (one of the newly touching fingers) and AGM contains
                 * SGM's previous slot.
                 *
                 * Otherwise, SGM now contains slot 0 and AGM contains slot 2.
                 */
                if (old->sgm >= 2)
                        synaptics_mt_state_set(mt_state, 3, 0, old->sgm);
                else
                        synaptics_mt_state_set(mt_state, 3, 0, 2);
                break;
        case 2:
                /*
                 * If the AGM previously contained slot 3 or higher, then the
                 * newly touching finger is in the lowest available slot.
                 *
                 * If SGM was previously 1 or higher, then the new SGM is
                 * now slot 0 (with a new finger), otherwise, the new finger
                 * is now in a hidden slot between 0 and AGM's slot.
                 *
                 * In all such cases, the SGM now contains slot 0, and the AGM
                 * continues to contain the same slot as before.
                 */
                if (old->agm >= 3) {
                        synaptics_mt_state_set(mt_state, 3, 0, old->agm);
                        break;
                }

                /*
                 * After some 3->1 and all 3->2 transitions, we lose track
                 * of which slot is reported by SGM and AGM.
                 *
                 * For 2->3 in this state, report 3 fingers, but empty all
                 * slots, and we will guess (0,2) on a subsequent 0->3.
                 *
                 * To userspace, the resulting transition will look like:
                 *    2:[0,1] -> 3:[-1,-1] -> 3:[0,2]
                 */
                if (priv->mt_state_lost) {
                        synaptics_mt_state_set(mt_state, 3, -1, -1);
                        break;
                }

                /*
                 * If the (SGM,AGM) really previously contained slots (0, 1),
                 * then we cannot know what slot was just reported by the AGM,
                 * because the 2->3 transition can occur either before or after
                 * the AGM packet. Thus, this most recent AGM could contain
                 * either the same old slot 1 or the new slot 2.
                 * Subsequent AGMs will be reporting slot 2.
                 *
                 * To userspace, the resulting transition will look like:
                 *    2:[0,1] -> 3:[0,-1] -> 3:[0,2]
                 */
                synaptics_mt_state_set(mt_state, 3, 0, -1);
                break;
        case 3:
                /*
                 * If, for whatever reason, the previous agm was invalid,
                 * Assume SGM now contains slot 0, AGM now contains slot 2.
                 */
                if (old->agm <= 2)
                        synaptics_mt_state_set(mt_state, 3, 0, 2);
                /*
                 * mt_state either hasn't changed, or was updated by a recently
                 * received AGM-CONTACT packet.
                 */
                break;

        case 4:
        case 5:
                /* mt_state was updated by AGM-CONTACT packet */
                break;
        }
}

/* Handle case where mt_state->count = 4, or = 5 */
static void synaptics_image_sensor_45f(struct synaptics_data *priv,
                                       struct synaptics_mt_state *mt_state)
{
        /* mt_state was updated correctly by AGM-CONTACT packet */
        priv->mt_state_lost = false;
}

static void synaptics_image_sensor_process(struct psmouse *psmouse,
                                           struct synaptics_hw_state *sgm)
{
        struct synaptics_data *priv = psmouse->private;
        struct synaptics_hw_state *agm = &priv->agm;
        struct synaptics_mt_state mt_state;

        /* Initialize using current mt_state (as updated by last agm) */
        mt_state = agm->mt_state;

        /*
         * Update mt_state using the new finger count and current mt_state.
         */
        if (sgm->z == 0)
                synaptics_image_sensor_0f(priv, &mt_state);
        else if (sgm->w >= 4)
                synaptics_image_sensor_1f(priv, &mt_state);
        else if (sgm->w == 0)
                synaptics_image_sensor_2f(priv, &mt_state);
        else if (sgm->w == 1 && mt_state.count <= 3)
                synaptics_image_sensor_3f(priv, &mt_state);
        else
                synaptics_image_sensor_45f(priv, &mt_state);

        /* Send resulting input events to user space */
        synaptics_report_mt_data(psmouse, &mt_state, sgm);

        /* Store updated mt_state */
        priv->mt_state = agm->mt_state = mt_state;
        priv->agm_pending = false;
}

static void synaptics_profile_sensor_process(struct psmouse *psmouse,
                                             struct synaptics_hw_state *sgm,
                                             int num_fingers)
{
        struct input_dev *dev = psmouse->dev;
        struct synaptics_data *priv = psmouse->private;
        struct synaptics_hw_state *hw[2] = { sgm, &priv->agm };
        struct input_mt_pos pos[2];
        int slot[2], nsemi, i;

        nsemi = clamp_val(num_fingers, 0, 2);

        for (i = 0; i < nsemi; i++) {
                pos[i].x = hw[i]->x;
                pos[i].y = synaptics_invert_y(hw[i]->y);
        }

        input_mt_assign_slots(dev, slot, pos, nsemi);

        for (i = 0; i < nsemi; i++) {
                input_mt_slot(dev, slot[i]);
                input_mt_report_slot_state(dev, MT_TOOL_FINGER, true);
                input_report_abs(dev, ABS_MT_POSITION_X, pos[i].x);
                input_report_abs(dev, ABS_MT_POSITION_Y, pos[i].y);
                input_report_abs(dev, ABS_MT_PRESSURE, hw[i]->z);
        }

        input_mt_drop_unused(dev);
        input_mt_report_pointer_emulation(dev, false);
        input_mt_report_finger_count(dev, num_fingers);

        synaptics_report_buttons(psmouse, sgm);

        input_sync(dev);
}

/*
 *  called for each full received packet from the touchpad
 */
static void synaptics_process_packet(struct psmouse *psmouse)
{
        struct input_dev *dev = psmouse->dev;
        struct synaptics_data *priv = psmouse->private;
        struct synaptics_hw_state hw;
        int num_fingers;
        int finger_width;

        if (synaptics_parse_hw_state(psmouse->packet, priv, &hw))
                return;

        if (SYN_CAP_IMAGE_SENSOR(priv->ext_cap_0c)) {
                synaptics_image_sensor_process(psmouse, &hw);
                return;
        }

        if (hw.scroll) {
                priv->scroll += hw.scroll;

                while (priv->scroll >= 4) {
                        input_report_key(dev, BTN_BACK, !hw.down);
                        input_sync(dev);
                        input_report_key(dev, BTN_BACK, hw.down);
                        input_sync(dev);
                        priv->scroll -= 4;
                }
                while (priv->scroll <= -4) {
                        input_report_key(dev, BTN_FORWARD, !hw.up);
                        input_sync(dev);
                        input_report_key(dev, BTN_FORWARD, hw.up);
                        input_sync(dev);
                        priv->scroll += 4;
                }
                return;
        }

        if (hw.z > 0 && hw.x > 1) {
                num_fingers = 1;
                finger_width = 5;
                if (SYN_CAP_EXTENDED(priv->capabilities)) {
                        switch (hw.w) {
                        case 0 ... 1:
                                if (SYN_CAP_MULTIFINGER(priv->capabilities))
                                        num_fingers = hw.w + 2;
                                break;
                        case 2:
                                if (SYN_MODEL_PEN(priv->model_id))
                                        ;   /* Nothing, treat a pen as a single finger */
                                break;
                        case 4 ... 15:
                                if (SYN_CAP_PALMDETECT(priv->capabilities))
                                        finger_width = hw.w;
                                break;
                        }
                }
        } else {
                num_fingers = 0;
                finger_width = 0;
        }

        if (cr48_profile_sensor) {
                synaptics_profile_sensor_process(psmouse, &hw, num_fingers);
                return;
        }

        if (SYN_CAP_ADV_GESTURE(priv->ext_cap_0c))
                synaptics_report_semi_mt_data(dev, &hw, &priv->agm,
                                              num_fingers);

        /* Post events
         * BTN_TOUCH has to be first as mousedev relies on it when doing
         * absolute -> relative conversion
         */
        if (hw.z > 30) input_report_key(dev, BTN_TOUCH, 1);
        if (hw.z < 25) input_report_key(dev, BTN_TOUCH, 0);

        if (num_fingers > 0) {
                input_report_abs(dev, ABS_X, hw.x);
                input_report_abs(dev, ABS_Y, synaptics_invert_y(hw.y));
        }
        input_report_abs(dev, ABS_PRESSURE, hw.z);

        if (SYN_CAP_PALMDETECT(priv->capabilities))
                input_report_abs(dev, ABS_TOOL_WIDTH, finger_width);

        input_report_key(dev, BTN_TOOL_FINGER, num_fingers == 1);
        if (SYN_CAP_MULTIFINGER(priv->capabilities)) {
                input_report_key(dev, BTN_TOOL_DOUBLETAP, num_fingers == 2);
                input_report_key(dev, BTN_TOOL_TRIPLETAP, num_fingers == 3);
        }

        synaptics_report_buttons(psmouse, &hw);

        input_sync(dev);
}

static int synaptics_validate_byte(struct psmouse *psmouse,
                                   int idx, unsigned char pkt_type)
{
        static const unsigned char newabs_mask[]        = { 0xC8, 0x00, 0x00, 0xC8, 0x00 };
        static const unsigned char newabs_rel_mask[]    = { 0xC0, 0x00, 0x00, 0xC0, 0x00 };
        static const unsigned char newabs_rslt[]        = { 0x80, 0x00, 0x00, 0xC0, 0x00 };
        static const unsigned char oldabs_mask[]        = { 0xC0, 0x60, 0x00, 0xC0, 0x60 };
        static const unsigned char oldabs_rslt[]        = { 0xC0, 0x00, 0x00, 0x80, 0x00 };
        const char *packet = psmouse->packet;

        if (idx < 0 || idx > 4)
                return 0;

        switch (pkt_type) {

        case SYN_NEWABS:
        case SYN_NEWABS_RELAXED:
                return (packet[idx] & newabs_rel_mask[idx]) == newabs_rslt[idx];

        case SYN_NEWABS_STRICT:
                return (packet[idx] & newabs_mask[idx]) == newabs_rslt[idx];

        case SYN_OLDABS:
                return (packet[idx] & oldabs_mask[idx]) == oldabs_rslt[idx];

        default:
                psmouse_err(psmouse, "unknown packet type %d\n", pkt_type);
                return 0;
        }
}

static unsigned char synaptics_detect_pkt_type(struct psmouse *psmouse)
{
        int i;

        for (i = 0; i < 5; i++)
                if (!synaptics_validate_byte(psmouse, i, SYN_NEWABS_STRICT)) {
                        psmouse_info(psmouse, "using relaxed packet validation\n");
                        return SYN_NEWABS_RELAXED;
                }

        return SYN_NEWABS_STRICT;
}

static psmouse_ret_t synaptics_process_byte(struct psmouse *psmouse)
{
        struct synaptics_data *priv = psmouse->private;

        if (psmouse->pktcnt >= 6) { /* Full packet received */
                if (unlikely(priv->pkt_type == SYN_NEWABS))
                        priv->pkt_type = synaptics_detect_pkt_type(psmouse);

                if (SYN_CAP_PASS_THROUGH(priv->capabilities) &&
                    synaptics_is_pt_packet(psmouse->packet)) {
                        if (priv->pt_port)
                                synaptics_pass_pt_packet(priv->pt_port, psmouse->packet);
                } else
                        synaptics_process_packet(psmouse);

                return PSMOUSE_FULL_PACKET;
        }

        return synaptics_validate_byte(psmouse, psmouse->pktcnt - 1, priv->pkt_type) ?
                PSMOUSE_GOOD_DATA : PSMOUSE_BAD_DATA;
}

/*****************************************************************************
 *      Driver initialization/cleanup functions
 ****************************************************************************/
static void set_abs_position_params(struct input_dev *dev,
                                    struct synaptics_data *priv, int x_code,
                                    int y_code)
{
        int x_min = priv->x_min ?: XMIN_NOMINAL;
        int x_max = priv->x_max ?: XMAX_NOMINAL;
        int y_min = priv->y_min ?: YMIN_NOMINAL;
        int y_max = priv->y_max ?: YMAX_NOMINAL;
        int fuzz = SYN_CAP_REDUCED_FILTERING(priv->ext_cap_0c) ?
                        SYN_REDUCED_FILTER_FUZZ : 0;

        input_set_abs_params(dev, x_code, x_min, x_max, fuzz, 0);
        input_set_abs_params(dev, y_code, y_min, y_max, fuzz, 0);
        input_abs_set_res(dev, x_code, priv->x_res);
        input_abs_set_res(dev, y_code, priv->y_res);
}

static void set_input_params(struct psmouse *psmouse,
                             struct synaptics_data *priv)
{
        struct input_dev *dev = psmouse->dev;
        int i;

        /* Things that apply to both modes */
        __set_bit(INPUT_PROP_POINTER, dev->propbit);
        __set_bit(EV_KEY, dev->evbit);
        __set_bit(BTN_LEFT, dev->keybit);
        __set_bit(BTN_RIGHT, dev->keybit);

        if (SYN_CAP_MIDDLE_BUTTON(priv->capabilities))
                __set_bit(BTN_MIDDLE, dev->keybit);

        if (!priv->absolute_mode) {
                /* Relative mode */
                __set_bit(EV_REL, dev->evbit);
                __set_bit(REL_X, dev->relbit);
                __set_bit(REL_Y, dev->relbit);
                return;
        }

        /* Absolute mode */
        __set_bit(EV_ABS, dev->evbit);
        set_abs_position_params(dev, priv, ABS_X, ABS_Y);
        input_set_abs_params(dev, ABS_PRESSURE, 0, 255, 0, 0);

        if (cr48_profile_sensor)
                input_set_abs_params(dev, ABS_MT_PRESSURE, 0, 255, 0, 0);

        if (SYN_CAP_IMAGE_SENSOR(priv->ext_cap_0c)) {
                set_abs_position_params(dev, priv, ABS_MT_POSITION_X,
                                        ABS_MT_POSITION_Y);
                /* Image sensors can report per-contact pressure */
                input_set_abs_params(dev, ABS_MT_PRESSURE, 0, 255, 0, 0);
                input_mt_init_slots(dev, 2, INPUT_MT_POINTER);

                /* Image sensors can signal 4 and 5 finger clicks */
                __set_bit(BTN_TOOL_QUADTAP, dev->keybit);
                __set_bit(BTN_TOOL_QUINTTAP, dev->keybit);
        } else if (SYN_CAP_ADV_GESTURE(priv->ext_cap_0c)) {
                set_abs_position_params(dev, priv, ABS_MT_POSITION_X,
                                        ABS_MT_POSITION_Y);
                /*
                 * Profile sensor in CR-48 tracks contacts reasonably well,
                 * other non-image sensors with AGM use semi-mt.
                 */
                input_mt_init_slots(dev, 2,
                                    INPUT_MT_POINTER |
                                    (cr48_profile_sensor ?
                                        INPUT_MT_TRACK : INPUT_MT_SEMI_MT));
        }

        if (SYN_CAP_PALMDETECT(priv->capabilities))
                input_set_abs_params(dev, ABS_TOOL_WIDTH, 0, 15, 0, 0);

        __set_bit(BTN_TOUCH, dev->keybit);
        __set_bit(BTN_TOOL_FINGER, dev->keybit);

        if (SYN_CAP_MULTIFINGER(priv->capabilities)) {
                __set_bit(BTN_TOOL_DOUBLETAP, dev->keybit);
                __set_bit(BTN_TOOL_TRIPLETAP, dev->keybit);
        }

        if (SYN_CAP_FOUR_BUTTON(priv->capabilities) ||
            SYN_CAP_MIDDLE_BUTTON(priv->capabilities)) {
                __set_bit(BTN_FORWARD, dev->keybit);
                __set_bit(BTN_BACK, dev->keybit);
        }

        for (i = 0; i < SYN_CAP_MULTI_BUTTON_NO(priv->ext_cap); i++)
                __set_bit(BTN_0 + i, dev->keybit);

        __clear_bit(EV_REL, dev->evbit);
        __clear_bit(REL_X, dev->relbit);
        __clear_bit(REL_Y, dev->relbit);

        if (SYN_CAP_CLICKPAD(priv->ext_cap_0c)) {
                __set_bit(INPUT_PROP_BUTTONPAD, dev->propbit);
                if (psmouse_matches_pnp_id(psmouse, topbuttonpad_pnp_ids) &&
                    !SYN_CAP_EXT_BUTTONS_STICK(priv->ext_cap_10))
                        __set_bit(INPUT_PROP_TOPBUTTONPAD, dev->propbit);
                /* Clickpads report only left button */
                __clear_bit(BTN_RIGHT, dev->keybit);
                __clear_bit(BTN_MIDDLE, dev->keybit);
        }
}

static ssize_t synaptics_show_disable_gesture(struct psmouse *psmouse,
                                              void *data, char *buf)
{
        struct synaptics_data *priv = psmouse->private;

        return sprintf(buf, "%c\n", priv->disable_gesture ? '1' : '0');
}

static ssize_t synaptics_set_disable_gesture(struct psmouse *psmouse,
                                             void *data, const char *buf,
                                             size_t len)
{
        struct synaptics_data *priv = psmouse->private;
        unsigned int value;
        int err;

        err = kstrtouint(buf, 10, &value);
        if (err)
                return err;

        if (value > 1)
                return -EINVAL;

        if (value == priv->disable_gesture)
                return len;

        priv->disable_gesture = value;
        if (value)
                priv->mode |= SYN_BIT_DISABLE_GESTURE;
        else
                priv->mode &= ~SYN_BIT_DISABLE_GESTURE;

        if (synaptics_mode_cmd(psmouse, priv->mode))
                return -EIO;

        return len;
}

PSMOUSE_DEFINE_ATTR(disable_gesture, S_IWUSR | S_IRUGO, NULL,
                    synaptics_show_disable_gesture,
                    synaptics_set_disable_gesture);

static void synaptics_disconnect(struct psmouse *psmouse)
{
        struct synaptics_data *priv = psmouse->private;

        if (!priv->absolute_mode && SYN_ID_DISGEST_SUPPORTED(priv->identity))
                device_remove_file(&psmouse->ps2dev.serio->dev,
                                   &psmouse_attr_disable_gesture.dattr);

        synaptics_reset(psmouse);
        kfree(priv);
        psmouse->private = NULL;
}

static int synaptics_reconnect(struct psmouse *psmouse)
{
        struct synaptics_data *priv = psmouse->private;
        struct synaptics_data old_priv = *priv;
        unsigned char param[2];
        int retry = 0;
        int error;

        do {
                psmouse_reset(psmouse);
                if (retry) {
                        /*
                         * On some boxes, right after resuming, the touchpad
                         * needs some time to finish initializing (I assume
                         * it needs time to calibrate) and start responding
                         * to Synaptics-specific queries, so let's wait a
                         * bit.
                         */
                        ssleep(1);
                }
                ps2_command(&psmouse->ps2dev, param, PSMOUSE_CMD_GETID);
                error = synaptics_detect(psmouse, 0);
        } while (error && ++retry < 3);

        if (error)
                return -1;

        if (retry > 1)
                psmouse_dbg(psmouse, "reconnected after %d tries\n", retry);

        if (synaptics_query_hardware(psmouse)) {
                psmouse_err(psmouse, "Unable to query device.\n");
                return -1;
        }

        if (synaptics_set_mode(psmouse)) {
                psmouse_err(psmouse, "Unable to initialize device.\n");
                return -1;
        }

        if (old_priv.identity != priv->identity ||
            old_priv.model_id != priv->model_id ||
            old_priv.capabilities != priv->capabilities ||
            old_priv.ext_cap != priv->ext_cap) {
                psmouse_err(psmouse,
                            "hardware appears to be different: id(%ld-%ld), model(%ld-%ld), caps(%lx-%lx), ext(%lx-%lx).\n",
                            old_priv.identity, priv->identity,
                            old_priv.model_id, priv->model_id,
                            old_priv.capabilities, priv->capabilities,
                            old_priv.ext_cap, priv->ext_cap);
                return -1;
        }

        return 0;
}

static bool impaired_toshiba_kbc;

static const struct dmi_system_id toshiba_dmi_table[] __initconst = {
#if defined(CONFIG_DMI) && defined(CONFIG_X86)
        {
                /* Toshiba Satellite */
                .matches = {
                        DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
                        DMI_MATCH(DMI_PRODUCT_NAME, "Satellite"),
                },
        },
        {
                /* Toshiba Dynabook */
                .matches = {
                        DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
                        DMI_MATCH(DMI_PRODUCT_NAME, "dynabook"),
                },
        },
        {
                /* Toshiba Portege M300 */
                .matches = {
                        DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
                        DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE M300"),
                },

        },
        {
                /* Toshiba Portege M300 */
                .matches = {
                        DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
                        DMI_MATCH(DMI_PRODUCT_NAME, "Portable PC"),
                        DMI_MATCH(DMI_PRODUCT_VERSION, "Version 1.0"),
                },

        },
#endif
        { }
};

static bool broken_olpc_ec;

static const struct dmi_system_id olpc_dmi_table[] __initconst = {
#if defined(CONFIG_DMI) && defined(CONFIG_OLPC)
        {
                /* OLPC XO-1 or XO-1.5 */
                .matches = {
                        DMI_MATCH(DMI_SYS_VENDOR, "OLPC"),
                        DMI_MATCH(DMI_PRODUCT_NAME, "XO"),
                },
        },
#endif
        { }
};

static const struct dmi_system_id __initconst cr48_dmi_table[] = {
#if defined(CONFIG_DMI) && defined(CONFIG_X86)
        {
                /* Cr-48 Chromebook (Codename Mario) */
                .matches = {
                        DMI_MATCH(DMI_SYS_VENDOR, "IEC"),
                        DMI_MATCH(DMI_PRODUCT_NAME, "Mario"),
                },
        },
#endif
        { }
};

static const struct dmi_system_id forcepad_dmi_table[] __initconst = {
#if defined(CONFIG_DMI) && defined(CONFIG_X86)
        {
                .matches = {
                        DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
                        DMI_MATCH(DMI_PRODUCT_NAME, "HP EliteBook Folio 1040 G1"),
                },
        },
#endif
        { }
};

void __init synaptics_module_init(void)
{
        impaired_toshiba_kbc = dmi_check_system(toshiba_dmi_table);
        broken_olpc_ec = dmi_check_system(olpc_dmi_table);
        cr48_profile_sensor = dmi_check_system(cr48_dmi_table);

        /*
         * Unfortunately ForcePad capability is not exported over PS/2,
         * so we have to resort to checking DMI.
         */
        is_forcepad = dmi_check_system(forcepad_dmi_table);
}

static int __synaptics_init(struct psmouse *psmouse, bool absolute_mode)
{
        struct synaptics_data *priv;
        int err = -1;

        /*
         * The OLPC XO has issues with Synaptics' absolute mode; the constant
         * packet spew overloads the EC such that key presses on the keyboard
         * are missed.  Given that, don't even attempt to use Absolute mode.
         * Relative mode seems to work just fine.
         */
        if (absolute_mode && broken_olpc_ec) {
                psmouse_info(psmouse,
                             "OLPC XO detected, not enabling Synaptics protocol.\n");
                return -ENODEV;
        }

        psmouse->private = priv = kzalloc(sizeof(struct synaptics_data), GFP_KERNEL);
        if (!priv)
                return -ENOMEM;

        psmouse_reset(psmouse);

        if (synaptics_query_hardware(psmouse)) {
                psmouse_err(psmouse, "Unable to query device.\n");
                goto init_fail;
        }

        priv->absolute_mode = absolute_mode;
        if (SYN_ID_DISGEST_SUPPORTED(priv->identity))
                priv->disable_gesture = true;

        if (synaptics_set_mode(psmouse)) {
                psmouse_err(psmouse, "Unable to initialize device.\n");
                goto init_fail;
        }

        priv->pkt_type = SYN_MODEL_NEWABS(priv->model_id) ? SYN_NEWABS : SYN_OLDABS;

        psmouse_info(psmouse,
                     "Touchpad model: %ld, fw: %ld.%ld, id: %#lx, caps: %#lx/%#lx/%#lx, board id: %lu, fw id: %lu\n",
                     SYN_ID_MODEL(priv->identity),
                     SYN_ID_MAJOR(priv->identity), SYN_ID_MINOR(priv->identity),
                     priv->model_id,
                     priv->capabilities, priv->ext_cap, priv->ext_cap_0c,
                     priv->board_id, priv->firmware_id);

        set_input_params(psmouse, priv);

        /*
         * Encode touchpad model so that it can be used to set
         * input device->id.version and be visible to userspace.
         * Because version is __u16 we have to drop something.
         * Hardware info bits seem to be good candidates as they
         * are documented to be for Synaptics corp. internal use.
         */
        psmouse->model = ((priv->model_id & 0x00ff0000) >> 8) |
                          (priv->model_id & 0x000000ff);

        if (absolute_mode) {
                psmouse->protocol_handler = synaptics_process_byte;
                psmouse->pktsize = 6;
        } else {
                /* Relative mode follows standard PS/2 mouse protocol */
                psmouse->protocol_handler = psmouse_process_byte;
                psmouse->pktsize = 3;
        }

        psmouse->set_rate = synaptics_set_rate;
        psmouse->disconnect = synaptics_disconnect;
        psmouse->reconnect = synaptics_reconnect;
        psmouse->cleanup = synaptics_reset;
        /* Synaptics can usually stay in sync without extra help */
        psmouse->resync_time = 0;

        if (SYN_CAP_PASS_THROUGH(priv->capabilities))
                synaptics_pt_create(psmouse);

        /*
         * Toshiba's KBC seems to have trouble handling data from
         * Synaptics at full rate.  Switch to a lower rate (roughly
         * the same rate as a standard PS/2 mouse).
         */
        if (psmouse->rate >= 80 && impaired_toshiba_kbc) {
                psmouse_info(psmouse,
                             "Toshiba %s detected, limiting rate to 40pps.\n",
                             dmi_get_system_info(DMI_PRODUCT_NAME));
                psmouse->rate = 40;
        }

        if (!priv->absolute_mode && SYN_ID_DISGEST_SUPPORTED(priv->identity)) {
                err = device_create_file(&psmouse->ps2dev.serio->dev,
                                         &psmouse_attr_disable_gesture.dattr);
                if (err) {
                        psmouse_err(psmouse,
                                    "Failed to create disable_gesture attribute (%d)",
                                    err);
                        goto init_fail;
                }
        }

        return 0;

 init_fail:
        kfree(priv);
        return err;
}

int synaptics_init(struct psmouse *psmouse)
{
        return __synaptics_init(psmouse, true);
}

int synaptics_init_relative(struct psmouse *psmouse)
{
        return __synaptics_init(psmouse, false);
}

bool synaptics_supported(void)
{
        return true;
}

#else /* CONFIG_MOUSE_PS2_SYNAPTICS */

void __init synaptics_module_init(void)
{
}

int synaptics_init(struct psmouse *psmouse)
{
        return -ENOSYS;
}

bool synaptics_supported(void)
{
        return false;
}

#endif /* CONFIG_MOUSE_PS2_SYNAPTICS */