Merge branch 'lpc32xx/dts' of git://git.antcom.de/linux-2.6 into next/dt

[platform/adaptation/renesas_rcar/renesas_kernel.git] / drivers / input / mouse / alps.c

/*
 * ALPS touchpad PS/2 mouse driver
 *
 * Copyright (c) 2003 Neil Brown <neilb@cse.unsw.edu.au>
 * Copyright (c) 2003-2005 Peter Osterlund <petero2@telia.com>
 * Copyright (c) 2004 Dmitry Torokhov <dtor@mail.ru>
 * Copyright (c) 2005 Vojtech Pavlik <vojtech@suse.cz>
 * Copyright (c) 2009 Sebastian Kapfer <sebastian_kapfer@gmx.net>
 *
 * ALPS detection, tap switching and status querying info is taken from
 * tpconfig utility (by C. Scott Ananian and Bruce Kall).
 *
 * 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.
 */

#include <linux/slab.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/serio.h>
#include <linux/libps2.h>

#include "psmouse.h"
#include "alps.h"

/*
 * Definitions for ALPS version 3 and 4 command mode protocol
 */
#define ALPS_V3_X_MAX   2000
#define ALPS_V3_Y_MAX   1400

#define ALPS_BITMAP_X_BITS      15
#define ALPS_BITMAP_Y_BITS      11

#define ALPS_CMD_NIBBLE_10      0x01f2

static const struct alps_nibble_commands alps_v3_nibble_commands[] = {
        { PSMOUSE_CMD_SETPOLL,          0x00 }, /* 0 */
        { PSMOUSE_CMD_RESET_DIS,        0x00 }, /* 1 */
        { PSMOUSE_CMD_SETSCALE21,       0x00 }, /* 2 */
        { PSMOUSE_CMD_SETRATE,          0x0a }, /* 3 */
        { PSMOUSE_CMD_SETRATE,          0x14 }, /* 4 */
        { PSMOUSE_CMD_SETRATE,          0x28 }, /* 5 */
        { PSMOUSE_CMD_SETRATE,          0x3c }, /* 6 */
        { PSMOUSE_CMD_SETRATE,          0x50 }, /* 7 */
        { PSMOUSE_CMD_SETRATE,          0x64 }, /* 8 */
        { PSMOUSE_CMD_SETRATE,          0xc8 }, /* 9 */
        { ALPS_CMD_NIBBLE_10,           0x00 }, /* a */
        { PSMOUSE_CMD_SETRES,           0x00 }, /* b */
        { PSMOUSE_CMD_SETRES,           0x01 }, /* c */
        { PSMOUSE_CMD_SETRES,           0x02 }, /* d */
        { PSMOUSE_CMD_SETRES,           0x03 }, /* e */
        { PSMOUSE_CMD_SETSCALE11,       0x00 }, /* f */
};

static const struct alps_nibble_commands alps_v4_nibble_commands[] = {
        { PSMOUSE_CMD_ENABLE,           0x00 }, /* 0 */
        { PSMOUSE_CMD_RESET_DIS,        0x00 }, /* 1 */
        { PSMOUSE_CMD_SETSCALE21,       0x00 }, /* 2 */
        { PSMOUSE_CMD_SETRATE,          0x0a }, /* 3 */
        { PSMOUSE_CMD_SETRATE,          0x14 }, /* 4 */
        { PSMOUSE_CMD_SETRATE,          0x28 }, /* 5 */
        { PSMOUSE_CMD_SETRATE,          0x3c }, /* 6 */
        { PSMOUSE_CMD_SETRATE,          0x50 }, /* 7 */
        { PSMOUSE_CMD_SETRATE,          0x64 }, /* 8 */
        { PSMOUSE_CMD_SETRATE,          0xc8 }, /* 9 */
        { ALPS_CMD_NIBBLE_10,           0x00 }, /* a */
        { PSMOUSE_CMD_SETRES,           0x00 }, /* b */
        { PSMOUSE_CMD_SETRES,           0x01 }, /* c */
        { PSMOUSE_CMD_SETRES,           0x02 }, /* d */
        { PSMOUSE_CMD_SETRES,           0x03 }, /* e */
        { PSMOUSE_CMD_SETSCALE11,       0x00 }, /* f */
};


#define ALPS_DUALPOINT          0x02    /* touchpad has trackstick */
#define ALPS_PASS               0x04    /* device has a pass-through port */

#define ALPS_WHEEL              0x08    /* hardware wheel present */
#define ALPS_FW_BK_1            0x10    /* front & back buttons present */
#define ALPS_FW_BK_2            0x20    /* front & back buttons present */
#define ALPS_FOUR_BUTTONS       0x40    /* 4 direction button present */
#define ALPS_PS2_INTERLEAVED    0x80    /* 3-byte PS/2 packet interleaved with
                                           6-byte ALPS packet */

static const struct alps_model_info alps_model_data[] = {
        { { 0x32, 0x02, 0x14 }, 0x00, ALPS_PROTO_V2, 0xf8, 0xf8, ALPS_PASS | ALPS_DUALPOINT },  /* Toshiba Salellite Pro M10 */
        { { 0x33, 0x02, 0x0a }, 0x00, ALPS_PROTO_V1, 0x88, 0xf8, 0 },                           /* UMAX-530T */
        { { 0x53, 0x02, 0x0a }, 0x00, ALPS_PROTO_V2, 0xf8, 0xf8, 0 },
        { { 0x53, 0x02, 0x14 }, 0x00, ALPS_PROTO_V2, 0xf8, 0xf8, 0 },
        { { 0x60, 0x03, 0xc8 }, 0x00, ALPS_PROTO_V2, 0xf8, 0xf8, 0 },                           /* HP ze1115 */
        { { 0x63, 0x02, 0x0a }, 0x00, ALPS_PROTO_V2, 0xf8, 0xf8, 0 },
        { { 0x63, 0x02, 0x14 }, 0x00, ALPS_PROTO_V2, 0xf8, 0xf8, 0 },
        { { 0x63, 0x02, 0x28 }, 0x00, ALPS_PROTO_V2, 0xf8, 0xf8, ALPS_FW_BK_2 },                /* Fujitsu Siemens S6010 */
        { { 0x63, 0x02, 0x3c }, 0x00, ALPS_PROTO_V2, 0x8f, 0x8f, ALPS_WHEEL },                  /* Toshiba Satellite S2400-103 */
        { { 0x63, 0x02, 0x50 }, 0x00, ALPS_PROTO_V2, 0xef, 0xef, ALPS_FW_BK_1 },                /* NEC Versa L320 */
        { { 0x63, 0x02, 0x64 }, 0x00, ALPS_PROTO_V2, 0xf8, 0xf8, 0 },
        { { 0x63, 0x03, 0xc8 }, 0x00, ALPS_PROTO_V2, 0xf8, 0xf8, ALPS_PASS | ALPS_DUALPOINT },  /* Dell Latitude D800 */
        { { 0x73, 0x00, 0x0a }, 0x00, ALPS_PROTO_V2, 0xf8, 0xf8, ALPS_DUALPOINT },              /* ThinkPad R61 8918-5QG */
        { { 0x73, 0x02, 0x0a }, 0x00, ALPS_PROTO_V2, 0xf8, 0xf8, 0 },
        { { 0x73, 0x02, 0x14 }, 0x00, ALPS_PROTO_V2, 0xf8, 0xf8, ALPS_FW_BK_2 },                /* Ahtec Laptop */
        { { 0x20, 0x02, 0x0e }, 0x00, ALPS_PROTO_V2, 0xf8, 0xf8, ALPS_PASS | ALPS_DUALPOINT },  /* XXX */
        { { 0x22, 0x02, 0x0a }, 0x00, ALPS_PROTO_V2, 0xf8, 0xf8, ALPS_PASS | ALPS_DUALPOINT },
        { { 0x22, 0x02, 0x14 }, 0x00, ALPS_PROTO_V2, 0xff, 0xff, ALPS_PASS | ALPS_DUALPOINT },  /* Dell Latitude D600 */
        /* Dell Latitude E5500, E6400, E6500, Precision M4400 */
        { { 0x62, 0x02, 0x14 }, 0x00, ALPS_PROTO_V2, 0xcf, 0xcf,
                ALPS_PASS | ALPS_DUALPOINT | ALPS_PS2_INTERLEAVED },
        { { 0x73, 0x02, 0x50 }, 0x00, ALPS_PROTO_V2, 0xcf, 0xcf, ALPS_FOUR_BUTTONS },           /* Dell Vostro 1400 */
        { { 0x52, 0x01, 0x14 }, 0x00, ALPS_PROTO_V2, 0xff, 0xff,
                ALPS_PASS | ALPS_DUALPOINT | ALPS_PS2_INTERLEAVED },                            /* Toshiba Tecra A11-11L */
        { { 0x73, 0x02, 0x64 }, 0x9b, ALPS_PROTO_V3, 0x8f, 0x8f, ALPS_DUALPOINT },
        { { 0x73, 0x02, 0x64 }, 0x9d, ALPS_PROTO_V3, 0x8f, 0x8f, ALPS_DUALPOINT },
        { { 0x73, 0x02, 0x64 }, 0x8a, ALPS_PROTO_V4, 0x8f, 0x8f, 0 },
};

/*
 * XXX - this entry is suspicious. First byte has zero lower nibble,
 * which is what a normal mouse would report. Also, the value 0x0e
 * isn't valid per PS/2 spec.
 */

/* Packet formats are described in Documentation/input/alps.txt */

static bool alps_is_valid_first_byte(const struct alps_model_info *model,
                                     unsigned char data)
{
        return (data & model->mask0) == model->byte0;
}

static void alps_report_buttons(struct psmouse *psmouse,
                                struct input_dev *dev1, struct input_dev *dev2,
                                int left, int right, int middle)
{
        struct input_dev *dev;

        /*
         * If shared button has already been reported on the
         * other device (dev2) then this event should be also
         * sent through that device.
         */
        dev = test_bit(BTN_LEFT, dev2->key) ? dev2 : dev1;
        input_report_key(dev, BTN_LEFT, left);

        dev = test_bit(BTN_RIGHT, dev2->key) ? dev2 : dev1;
        input_report_key(dev, BTN_RIGHT, right);

        dev = test_bit(BTN_MIDDLE, dev2->key) ? dev2 : dev1;
        input_report_key(dev, BTN_MIDDLE, middle);

        /*
         * Sync the _other_ device now, we'll do the first
         * device later once we report the rest of the events.
         */
        input_sync(dev2);
}

static void alps_process_packet_v1_v2(struct psmouse *psmouse)
{
        struct alps_data *priv = psmouse->private;
        const struct alps_model_info *model = priv->i;
        unsigned char *packet = psmouse->packet;
        struct input_dev *dev = psmouse->dev;
        struct input_dev *dev2 = priv->dev2;
        int x, y, z, ges, fin, left, right, middle;
        int back = 0, forward = 0;

        if (model->proto_version == ALPS_PROTO_V1) {
                left = packet[2] & 0x10;
                right = packet[2] & 0x08;
                middle = 0;
                x = packet[1] | ((packet[0] & 0x07) << 7);
                y = packet[4] | ((packet[3] & 0x07) << 7);
                z = packet[5];
        } else {
                left = packet[3] & 1;
                right = packet[3] & 2;
                middle = packet[3] & 4;
                x = packet[1] | ((packet[2] & 0x78) << (7 - 3));
                y = packet[4] | ((packet[3] & 0x70) << (7 - 4));
                z = packet[5];
        }

        if (model->flags & ALPS_FW_BK_1) {
                back = packet[0] & 0x10;
                forward = packet[2] & 4;
        }

        if (model->flags & ALPS_FW_BK_2) {
                back = packet[3] & 4;
                forward = packet[2] & 4;
                if ((middle = forward && back))
                        forward = back = 0;
        }

        ges = packet[2] & 1;
        fin = packet[2] & 2;

        if ((model->flags & ALPS_DUALPOINT) && z == 127) {
                input_report_rel(dev2, REL_X,  (x > 383 ? (x - 768) : x));
                input_report_rel(dev2, REL_Y, -(y > 255 ? (y - 512) : y));

                alps_report_buttons(psmouse, dev2, dev, left, right, middle);

                input_sync(dev2);
                return;
        }

        alps_report_buttons(psmouse, dev, dev2, left, right, middle);

        /* Convert hardware tap to a reasonable Z value */
        if (ges && !fin)
                z = 40;

        /*
         * A "tap and drag" operation is reported by the hardware as a transition
         * from (!fin && ges) to (fin && ges). This should be translated to the
         * sequence Z>0, Z==0, Z>0, so the Z==0 event has to be generated manually.
         */
        if (ges && fin && !priv->prev_fin) {
                input_report_abs(dev, ABS_X, x);
                input_report_abs(dev, ABS_Y, y);
                input_report_abs(dev, ABS_PRESSURE, 0);
                input_report_key(dev, BTN_TOOL_FINGER, 0);
                input_sync(dev);
        }
        priv->prev_fin = fin;

        if (z > 30)
                input_report_key(dev, BTN_TOUCH, 1);
        if (z < 25)
                input_report_key(dev, BTN_TOUCH, 0);

        if (z > 0) {
                input_report_abs(dev, ABS_X, x);
                input_report_abs(dev, ABS_Y, y);
        }

        input_report_abs(dev, ABS_PRESSURE, z);
        input_report_key(dev, BTN_TOOL_FINGER, z > 0);

        if (model->flags & ALPS_WHEEL)
                input_report_rel(dev, REL_WHEEL, ((packet[2] << 1) & 0x08) - ((packet[0] >> 4) & 0x07));

        if (model->flags & (ALPS_FW_BK_1 | ALPS_FW_BK_2)) {
                input_report_key(dev, BTN_FORWARD, forward);
                input_report_key(dev, BTN_BACK, back);
        }

        if (model->flags & ALPS_FOUR_BUTTONS) {
                input_report_key(dev, BTN_0, packet[2] & 4);
                input_report_key(dev, BTN_1, packet[0] & 0x10);
                input_report_key(dev, BTN_2, packet[3] & 4);
                input_report_key(dev, BTN_3, packet[0] & 0x20);
        }

        input_sync(dev);
}

/*
 * Process bitmap data from v3 and v4 protocols. Returns the number of
 * fingers detected. A return value of 0 means at least one of the
 * bitmaps was empty.
 *
 * The bitmaps don't have enough data to track fingers, so this function
 * only generates points representing a bounding box of all contacts.
 * These points are returned in x1, y1, x2, and y2 when the return value
 * is greater than 0.
 */
static int alps_process_bitmap(unsigned int x_map, unsigned int y_map,
                               int *x1, int *y1, int *x2, int *y2)
{
        struct alps_bitmap_point {
                int start_bit;
                int num_bits;
        };

        int fingers_x = 0, fingers_y = 0, fingers;
        int i, bit, prev_bit;
        struct alps_bitmap_point x_low = {0,}, x_high = {0,};
        struct alps_bitmap_point y_low = {0,}, y_high = {0,};
        struct alps_bitmap_point *point;

        if (!x_map || !y_map)
                return 0;

        *x1 = *y1 = *x2 = *y2 = 0;

        prev_bit = 0;
        point = &x_low;
        for (i = 0; x_map != 0; i++, x_map >>= 1) {
                bit = x_map & 1;
                if (bit) {
                        if (!prev_bit) {
                                point->start_bit = i;
                                fingers_x++;
                        }
                        point->num_bits++;
                } else {
                        if (prev_bit)
                                point = &x_high;
                        else
                                point->num_bits = 0;
                }
                prev_bit = bit;
        }

        /*
         * y bitmap is reversed for what we need (lower positions are in
         * higher bits), so we process from the top end.
         */
        y_map = y_map << (sizeof(y_map) * BITS_PER_BYTE - ALPS_BITMAP_Y_BITS);
        prev_bit = 0;
        point = &y_low;
        for (i = 0; y_map != 0; i++, y_map <<= 1) {
                bit = y_map & (1 << (sizeof(y_map) * BITS_PER_BYTE - 1));
                if (bit) {
                        if (!prev_bit) {
                                point->start_bit = i;
                                fingers_y++;
                        }
                        point->num_bits++;
                } else {
                        if (prev_bit)
                                point = &y_high;
                        else
                                point->num_bits = 0;
                }
                prev_bit = bit;
        }

        /*
         * Fingers can overlap, so we use the maximum count of fingers
         * on either axis as the finger count.
         */
        fingers = max(fingers_x, fingers_y);

        /*
         * If total fingers is > 1 but either axis reports only a single
         * contact, we have overlapping or adjacent fingers. For the
         * purposes of creating a bounding box, divide the single contact
         * (roughly) equally between the two points.
         */
        if (fingers > 1) {
                if (fingers_x == 1) {
                        i = x_low.num_bits / 2;
                        x_low.num_bits = x_low.num_bits - i;
                        x_high.start_bit = x_low.start_bit + i;
                        x_high.num_bits = max(i, 1);
                } else if (fingers_y == 1) {
                        i = y_low.num_bits / 2;
                        y_low.num_bits = y_low.num_bits - i;
                        y_high.start_bit = y_low.start_bit + i;
                        y_high.num_bits = max(i, 1);
                }
        }

        *x1 = (ALPS_V3_X_MAX * (2 * x_low.start_bit + x_low.num_bits - 1)) /
              (2 * (ALPS_BITMAP_X_BITS - 1));
        *y1 = (ALPS_V3_Y_MAX * (2 * y_low.start_bit + y_low.num_bits - 1)) /
              (2 * (ALPS_BITMAP_Y_BITS - 1));

        if (fingers > 1) {
                *x2 = (ALPS_V3_X_MAX * (2 * x_high.start_bit + x_high.num_bits - 1)) /
                      (2 * (ALPS_BITMAP_X_BITS - 1));
                *y2 = (ALPS_V3_Y_MAX * (2 * y_high.start_bit + y_high.num_bits - 1)) /
                      (2 * (ALPS_BITMAP_Y_BITS - 1));
        }

        return fingers;
}

static void alps_set_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, y);
        }
}

static void alps_report_semi_mt_data(struct input_dev *dev, int num_fingers,
                                     int x1, int y1, int x2, int y2)
{
        alps_set_slot(dev, 0, num_fingers != 0, x1, y1);
        alps_set_slot(dev, 1, num_fingers == 2, x2, y2);
}

static void alps_process_trackstick_packet_v3(struct psmouse *psmouse)
{
        struct alps_data *priv = psmouse->private;
        unsigned char *packet = psmouse->packet;
        struct input_dev *dev = priv->dev2;
        int x, y, z, left, right, middle;

        /* Sanity check packet */
        if (!(packet[0] & 0x40)) {
                psmouse_dbg(psmouse, "Bad trackstick packet, discarding\n");
                return;
        }

        /*
         * There's a special packet that seems to indicate the end
         * of a stream of trackstick data. Filter these out.
         */
        if (packet[1] == 0x7f && packet[2] == 0x7f && packet[4] == 0x7f)
                return;

        x = (s8)(((packet[0] & 0x20) << 2) | (packet[1] & 0x7f));
        y = (s8)(((packet[0] & 0x10) << 3) | (packet[2] & 0x7f));
        z = (packet[4] & 0x7c) >> 2;

        /*
         * The x and y values tend to be quite large, and when used
         * alone the trackstick is difficult to use. Scale them down
         * to compensate.
         */
        x /= 8;
        y /= 8;

        input_report_rel(dev, REL_X, x);
        input_report_rel(dev, REL_Y, -y);

        /*
         * Most ALPS models report the trackstick buttons in the touchpad
         * packets, but a few report them here. No reliable way has been
         * found to differentiate between the models upfront, so we enable
         * the quirk in response to seeing a button press in the trackstick
         * packet.
         */
        left = packet[3] & 0x01;
        right = packet[3] & 0x02;
        middle = packet[3] & 0x04;

        if (!(priv->quirks & ALPS_QUIRK_TRACKSTICK_BUTTONS) &&
            (left || right || middle))
                priv->quirks |= ALPS_QUIRK_TRACKSTICK_BUTTONS;

        if (priv->quirks & ALPS_QUIRK_TRACKSTICK_BUTTONS) {
                input_report_key(dev, BTN_LEFT, left);
                input_report_key(dev, BTN_RIGHT, right);
                input_report_key(dev, BTN_MIDDLE, middle);
        }

        input_sync(dev);
        return;
}

static void alps_process_touchpad_packet_v3(struct psmouse *psmouse)
{
        struct alps_data *priv = psmouse->private;
        unsigned char *packet = psmouse->packet;
        struct input_dev *dev = psmouse->dev;
        struct input_dev *dev2 = priv->dev2;
        int x, y, z;
        int left, right, middle;
        int x1 = 0, y1 = 0, x2 = 0, y2 = 0;
        int fingers = 0, bmap_fingers;
        unsigned int x_bitmap, y_bitmap;

        /*
         * There's no single feature of touchpad position and bitmap packets
         * that can be used to distinguish between them. We rely on the fact
         * that a bitmap packet should always follow a position packet with
         * bit 6 of packet[4] set.
         */
        if (priv->multi_packet) {
                /*
                 * Sometimes a position packet will indicate a multi-packet
                 * sequence, but then what follows is another position
                 * packet. Check for this, and when it happens process the
                 * position packet as usual.
                 */
                if (packet[0] & 0x40) {
                        fingers = (packet[5] & 0x3) + 1;
                        x_bitmap = ((packet[4] & 0x7e) << 8) |
                                   ((packet[1] & 0x7f) << 2) |
                                   ((packet[0] & 0x30) >> 4);
                        y_bitmap = ((packet[3] & 0x70) << 4) |
                                   ((packet[2] & 0x7f) << 1) |
                                   (packet[4] & 0x01);

                        bmap_fingers = alps_process_bitmap(x_bitmap, y_bitmap,
                                                           &x1, &y1, &x2, &y2);

                        /*
                         * We shouldn't report more than one finger if
                         * we don't have two coordinates.
                         */
                        if (fingers > 1 && bmap_fingers < 2)
                                fingers = bmap_fingers;

                        /* Now process position packet */
                        packet = priv->multi_data;
                } else {
                        priv->multi_packet = 0;
                }
        }

        /*
         * Bit 6 of byte 0 is not usually set in position packets. The only
         * times it seems to be set is in situations where the data is
         * suspect anyway, e.g. a palm resting flat on the touchpad. Given
         * this combined with the fact that this bit is useful for filtering
         * out misidentified bitmap packets, we reject anything with this
         * bit set.
         */
        if (packet[0] & 0x40)
                return;

        if (!priv->multi_packet && (packet[4] & 0x40)) {
                priv->multi_packet = 1;
                memcpy(priv->multi_data, packet, sizeof(priv->multi_data));
                return;
        }

        priv->multi_packet = 0;

        left = packet[3] & 0x01;
        right = packet[3] & 0x02;
        middle = packet[3] & 0x04;

        x = ((packet[1] & 0x7f) << 4) | ((packet[4] & 0x30) >> 2) |
            ((packet[0] & 0x30) >> 4);
        y = ((packet[2] & 0x7f) << 4) | (packet[4] & 0x0f);
        z = packet[5] & 0x7f;

        /*
         * Sometimes the hardware sends a single packet with z = 0
         * in the middle of a stream. Real releases generate packets
         * with x, y, and z all zero, so these seem to be flukes.
         * Ignore them.
         */
        if (x && y && !z)
                return;

        /*
         * If we don't have MT data or the bitmaps were empty, we have
         * to rely on ST data.
         */
        if (!fingers) {
                x1 = x;
                y1 = y;
                fingers = z > 0 ? 1 : 0;
        }

        if (z >= 64)
                input_report_key(dev, BTN_TOUCH, 1);
        else
                input_report_key(dev, BTN_TOUCH, 0);

        alps_report_semi_mt_data(dev, fingers, x1, y1, x2, y2);

        input_mt_report_finger_count(dev, fingers);

        input_report_key(dev, BTN_LEFT, left);
        input_report_key(dev, BTN_RIGHT, right);
        input_report_key(dev, BTN_MIDDLE, middle);

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

        input_sync(dev);

        if (!(priv->quirks & ALPS_QUIRK_TRACKSTICK_BUTTONS)) {
                left = packet[3] & 0x10;
                right = packet[3] & 0x20;
                middle = packet[3] & 0x40;

                input_report_key(dev2, BTN_LEFT, left);
                input_report_key(dev2, BTN_RIGHT, right);
                input_report_key(dev2, BTN_MIDDLE, middle);
                input_sync(dev2);
        }
}

static void alps_process_packet_v3(struct psmouse *psmouse)
{
        unsigned char *packet = psmouse->packet;

        /*
         * v3 protocol packets come in three types, two representing
         * touchpad data and one representing trackstick data.
         * Trackstick packets seem to be distinguished by always
         * having 0x3f in the last byte. This value has never been
         * observed in the last byte of either of the other types
         * of packets.
         */
        if (packet[5] == 0x3f) {
                alps_process_trackstick_packet_v3(psmouse);
                return;
        }

        alps_process_touchpad_packet_v3(psmouse);
}

static void alps_process_packet_v4(struct psmouse *psmouse)
{
        struct alps_data *priv = psmouse->private;
        unsigned char *packet = psmouse->packet;
        struct input_dev *dev = psmouse->dev;
        int offset;
        int x, y, z;
        int left, right;
        int x1, y1, x2, y2;
        int fingers = 0;
        unsigned int x_bitmap, y_bitmap;

        /*
         * v4 has a 6-byte encoding for bitmap data, but this data is
         * broken up between 3 normal packets. Use priv->multi_packet to
         * track our position in the bitmap packet.
         */
        if (packet[6] & 0x40) {
                /* sync, reset position */
                priv->multi_packet = 0;
        }

        if (WARN_ON_ONCE(priv->multi_packet > 2))
                return;

        offset = 2 * priv->multi_packet;
        priv->multi_data[offset] = packet[6];
        priv->multi_data[offset + 1] = packet[7];

        if (++priv->multi_packet > 2) {
                priv->multi_packet = 0;

                x_bitmap = ((priv->multi_data[2] & 0x1f) << 10) |
                           ((priv->multi_data[3] & 0x60) << 3) |
                           ((priv->multi_data[0] & 0x3f) << 2) |
                           ((priv->multi_data[1] & 0x60) >> 5);
                y_bitmap = ((priv->multi_data[5] & 0x01) << 10) |
                           ((priv->multi_data[3] & 0x1f) << 5) |
                            (priv->multi_data[1] & 0x1f);

                fingers = alps_process_bitmap(x_bitmap, y_bitmap,
                                              &x1, &y1, &x2, &y2);

                /* Store MT data.*/
                priv->fingers = fingers;
                priv->x1 = x1;
                priv->x2 = x2;
                priv->y1 = y1;
                priv->y2 = y2;
        }

        left = packet[4] & 0x01;
        right = packet[4] & 0x02;

        x = ((packet[1] & 0x7f) << 4) | ((packet[3] & 0x30) >> 2) |
            ((packet[0] & 0x30) >> 4);
        y = ((packet[2] & 0x7f) << 4) | (packet[3] & 0x0f);
        z = packet[5] & 0x7f;

        /*
         * If there were no contacts in the bitmap, use ST
         * points in MT reports.
         * If there were two contacts or more, report MT data.
         */
        if (priv->fingers < 2) {
                x1 = x;
                y1 = y;
                fingers = z > 0 ? 1 : 0;
        } else {
                fingers = priv->fingers;
                x1 = priv->x1;
                x2 = priv->x2;
                y1 = priv->y1;
                y2 = priv->y2;
        }

        if (z >= 64)
                input_report_key(dev, BTN_TOUCH, 1);
        else
                input_report_key(dev, BTN_TOUCH, 0);

        alps_report_semi_mt_data(dev, fingers, x1, y1, x2, y2);

        input_mt_report_finger_count(dev, fingers);

        input_report_key(dev, BTN_LEFT, left);
        input_report_key(dev, BTN_RIGHT, right);

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

        input_sync(dev);
}

static void alps_process_packet(struct psmouse *psmouse)
{
        struct alps_data *priv = psmouse->private;
        const struct alps_model_info *model = priv->i;

        switch (model->proto_version) {
        case ALPS_PROTO_V1:
        case ALPS_PROTO_V2:
                alps_process_packet_v1_v2(psmouse);
                break;
        case ALPS_PROTO_V3:
                alps_process_packet_v3(psmouse);
                break;
        case ALPS_PROTO_V4:
                alps_process_packet_v4(psmouse);
                break;
        }
}

static void alps_report_bare_ps2_packet(struct psmouse *psmouse,
                                        unsigned char packet[],
                                        bool report_buttons)
{
        struct alps_data *priv = psmouse->private;
        struct input_dev *dev2 = priv->dev2;

        if (report_buttons)
                alps_report_buttons(psmouse, dev2, psmouse->dev,
                                packet[0] & 1, packet[0] & 2, packet[0] & 4);

        input_report_rel(dev2, REL_X,
                packet[1] ? packet[1] - ((packet[0] << 4) & 0x100) : 0);
        input_report_rel(dev2, REL_Y,
                packet[2] ? ((packet[0] << 3) & 0x100) - packet[2] : 0);

        input_sync(dev2);
}

static psmouse_ret_t alps_handle_interleaved_ps2(struct psmouse *psmouse)
{
        struct alps_data *priv = psmouse->private;

        if (psmouse->pktcnt < 6)
                return PSMOUSE_GOOD_DATA;

        if (psmouse->pktcnt == 6) {
                /*
                 * Start a timer to flush the packet if it ends up last
                 * 6-byte packet in the stream. Timer needs to fire
                 * psmouse core times out itself. 20 ms should be enough
                 * to decide if we are getting more data or not.
                 */
                mod_timer(&priv->timer, jiffies + msecs_to_jiffies(20));
                return PSMOUSE_GOOD_DATA;
        }

        del_timer(&priv->timer);

        if (psmouse->packet[6] & 0x80) {

                /*
                 * Highest bit is set - that means we either had
                 * complete ALPS packet and this is start of the
                 * next packet or we got garbage.
                 */

                if (((psmouse->packet[3] |
                      psmouse->packet[4] |
                      psmouse->packet[5]) & 0x80) ||
                    (!alps_is_valid_first_byte(priv->i, psmouse->packet[6]))) {
                        psmouse_dbg(psmouse,
                                    "refusing packet %x %x %x %x (suspected interleaved ps/2)\n",
                                    psmouse->packet[3], psmouse->packet[4],
                                    psmouse->packet[5], psmouse->packet[6]);
                        return PSMOUSE_BAD_DATA;
                }

                alps_process_packet(psmouse);

                /* Continue with the next packet */
                psmouse->packet[0] = psmouse->packet[6];
                psmouse->pktcnt = 1;

        } else {

                /*
                 * High bit is 0 - that means that we indeed got a PS/2
                 * packet in the middle of ALPS packet.
                 *
                 * There is also possibility that we got 6-byte ALPS
                 * packet followed  by 3-byte packet from trackpoint. We
                 * can not distinguish between these 2 scenarios but
                 * because the latter is unlikely to happen in course of
                 * normal operation (user would need to press all
                 * buttons on the pad and start moving trackpoint
                 * without touching the pad surface) we assume former.
                 * Even if we are wrong the wost thing that would happen
                 * the cursor would jump but we should not get protocol
                 * de-synchronization.
                 */

                alps_report_bare_ps2_packet(psmouse, &psmouse->packet[3],
                                            false);

                /*
                 * Continue with the standard ALPS protocol handling,
                 * but make sure we won't process it as an interleaved
                 * packet again, which may happen if all buttons are
                 * pressed. To avoid this let's reset the 4th bit which
                 * is normally 1.
                 */
                psmouse->packet[3] = psmouse->packet[6] & 0xf7;
                psmouse->pktcnt = 4;
        }

        return PSMOUSE_GOOD_DATA;
}

static void alps_flush_packet(unsigned long data)
{
        struct psmouse *psmouse = (struct psmouse *)data;

        serio_pause_rx(psmouse->ps2dev.serio);

        if (psmouse->pktcnt == psmouse->pktsize) {

                /*
                 * We did not any more data in reasonable amount of time.
                 * Validate the last 3 bytes and process as a standard
                 * ALPS packet.
                 */
                if ((psmouse->packet[3] |
                     psmouse->packet[4] |
                     psmouse->packet[5]) & 0x80) {
                        psmouse_dbg(psmouse,
                                    "refusing packet %x %x %x (suspected interleaved ps/2)\n",
                                    psmouse->packet[3], psmouse->packet[4],
                                    psmouse->packet[5]);
                } else {
                        alps_process_packet(psmouse);
                }
                psmouse->pktcnt = 0;
        }

        serio_continue_rx(psmouse->ps2dev.serio);
}

static psmouse_ret_t alps_process_byte(struct psmouse *psmouse)
{
        struct alps_data *priv = psmouse->private;
        const struct alps_model_info *model = priv->i;

        if ((psmouse->packet[0] & 0xc8) == 0x08) { /* PS/2 packet */
                if (psmouse->pktcnt == 3) {
                        alps_report_bare_ps2_packet(psmouse, psmouse->packet,
                                                    true);
                        return PSMOUSE_FULL_PACKET;
                }
                return PSMOUSE_GOOD_DATA;
        }

        /* Check for PS/2 packet stuffed in the middle of ALPS packet. */

        if ((model->flags & ALPS_PS2_INTERLEAVED) &&
            psmouse->pktcnt >= 4 && (psmouse->packet[3] & 0x0f) == 0x0f) {
                return alps_handle_interleaved_ps2(psmouse);
        }

        if (!alps_is_valid_first_byte(model, psmouse->packet[0])) {
                psmouse_dbg(psmouse,
                            "refusing packet[0] = %x (mask0 = %x, byte0 = %x)\n",
                            psmouse->packet[0], model->mask0, model->byte0);
                return PSMOUSE_BAD_DATA;
        }

        /* Bytes 2 - pktsize should have 0 in the highest bit */
        if (psmouse->pktcnt >= 2 && psmouse->pktcnt <= psmouse->pktsize &&
            (psmouse->packet[psmouse->pktcnt - 1] & 0x80)) {
                psmouse_dbg(psmouse, "refusing packet[%i] = %x\n",
                            psmouse->pktcnt - 1,
                            psmouse->packet[psmouse->pktcnt - 1]);
                return PSMOUSE_BAD_DATA;
        }

        if (psmouse->pktcnt == psmouse->pktsize) {
                alps_process_packet(psmouse);
                return PSMOUSE_FULL_PACKET;
        }

        return PSMOUSE_GOOD_DATA;
}

static int alps_command_mode_send_nibble(struct psmouse *psmouse, int nibble)
{
        struct ps2dev *ps2dev = &psmouse->ps2dev;
        struct alps_data *priv = psmouse->private;
        int command;
        unsigned char *param;
        unsigned char dummy[4];

        BUG_ON(nibble > 0xf);

        command = priv->nibble_commands[nibble].command;
        param = (command & 0x0f00) ?
                dummy : (unsigned char *)&priv->nibble_commands[nibble].data;

        if (ps2_command(ps2dev, param, command))
                return -1;

        return 0;
}

static int alps_command_mode_set_addr(struct psmouse *psmouse, int addr)
{
        struct ps2dev *ps2dev = &psmouse->ps2dev;
        struct alps_data *priv = psmouse->private;
        int i, nibble;

        if (ps2_command(ps2dev, NULL, priv->addr_command))
                return -1;

        for (i = 12; i >= 0; i -= 4) {
                nibble = (addr >> i) & 0xf;
                if (alps_command_mode_send_nibble(psmouse, nibble))
                        return -1;
        }

        return 0;
}

static int __alps_command_mode_read_reg(struct psmouse *psmouse, int addr)
{
        struct ps2dev *ps2dev = &psmouse->ps2dev;
        unsigned char param[4];

        if (ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO))
                return -1;

        /*
         * The address being read is returned in the first two bytes
         * of the result. Check that this address matches the expected
         * address.
         */
        if (addr != ((param[0] << 8) | param[1]))
                return -1;

        return param[2];
}

static int alps_command_mode_read_reg(struct psmouse *psmouse, int addr)
{
        if (alps_command_mode_set_addr(psmouse, addr))
                return -1;
        return __alps_command_mode_read_reg(psmouse, addr);
}

static int __alps_command_mode_write_reg(struct psmouse *psmouse, u8 value)
{
        if (alps_command_mode_send_nibble(psmouse, (value >> 4) & 0xf))
                return -1;
        if (alps_command_mode_send_nibble(psmouse, value & 0xf))
                return -1;
        return 0;
}

static int alps_command_mode_write_reg(struct psmouse *psmouse, int addr,
                                       u8 value)
{
        if (alps_command_mode_set_addr(psmouse, addr))
                return -1;
        return __alps_command_mode_write_reg(psmouse, value);
}

static int alps_enter_command_mode(struct psmouse *psmouse,
                                   unsigned char *resp)
{
        unsigned char param[4];
        struct ps2dev *ps2dev = &psmouse->ps2dev;

        if (ps2_command(ps2dev, NULL, PSMOUSE_CMD_RESET_WRAP) ||
            ps2_command(ps2dev, NULL, PSMOUSE_CMD_RESET_WRAP) ||
            ps2_command(ps2dev, NULL, PSMOUSE_CMD_RESET_WRAP) ||
            ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO)) {
                psmouse_err(psmouse, "failed to enter command mode\n");
                return -1;
        }

        if (param[0] != 0x88 && param[1] != 0x07) {
                psmouse_dbg(psmouse,
                            "unknown response while entering command mode: %2.2x %2.2x %2.2x\n",
                            param[0], param[1], param[2]);
                return -1;
        }

        if (resp)
                *resp = param[2];
        return 0;
}

static inline int alps_exit_command_mode(struct psmouse *psmouse)
{
        struct ps2dev *ps2dev = &psmouse->ps2dev;
        if (ps2_command(ps2dev, NULL, PSMOUSE_CMD_SETSTREAM))
                return -1;
        return 0;
}

static const struct alps_model_info *alps_get_model(struct psmouse *psmouse, int *version)
{
        struct ps2dev *ps2dev = &psmouse->ps2dev;
        static const unsigned char rates[] = { 0, 10, 20, 40, 60, 80, 100, 200 };
        unsigned char param[4];
        const struct alps_model_info *model = NULL;
        int i;

        /*
         * First try "E6 report".
         * ALPS should return 0,0,10 or 0,0,100 if no buttons are pressed.
         * The bits 0-2 of the first byte will be 1s if some buttons are
         * pressed.
         */
        param[0] = 0;
        if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES) ||
            ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
            ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
            ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11))
                return NULL;

        param[0] = param[1] = param[2] = 0xff;
        if (ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO))
                return NULL;

        psmouse_dbg(psmouse, "E6 report: %2.2x %2.2x %2.2x",
                    param[0], param[1], param[2]);

        if ((param[0] & 0xf8) != 0 || param[1] != 0 ||
            (param[2] != 10 && param[2] != 100))
                return NULL;

        /*
         * Now try "E7 report". Allowed responses are in
         * alps_model_data[].signature
         */
        param[0] = 0;
        if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES) ||
            ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE21) ||
            ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE21) ||
            ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE21))
                return NULL;

        param[0] = param[1] = param[2] = 0xff;
        if (ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO))
                return NULL;

        psmouse_dbg(psmouse, "E7 report: %2.2x %2.2x %2.2x",
                    param[0], param[1], param[2]);

        if (version) {
                for (i = 0; i < ARRAY_SIZE(rates) && param[2] != rates[i]; i++)
                        /* empty */;
                *version = (param[0] << 8) | (param[1] << 4) | i;
        }

        for (i = 0; i < ARRAY_SIZE(alps_model_data); i++) {
                if (!memcmp(param, alps_model_data[i].signature,
                            sizeof(alps_model_data[i].signature))) {
                        model = alps_model_data + i;
                        break;
                }
        }

        if (model && model->proto_version > ALPS_PROTO_V2) {
                /*
                 * Need to check command mode response to identify
                 * model
                 */
                model = NULL;
                if (alps_enter_command_mode(psmouse, param)) {
                        psmouse_warn(psmouse,
                                     "touchpad failed to enter command mode\n");
                } else {
                        for (i = 0; i < ARRAY_SIZE(alps_model_data); i++) {
                                if (alps_model_data[i].proto_version > ALPS_PROTO_V2 &&
                                    alps_model_data[i].command_mode_resp == param[0]) {
                                        model = alps_model_data + i;
                                        break;
                                }
                        }
                        alps_exit_command_mode(psmouse);

                        if (!model)
                                psmouse_dbg(psmouse,
                                            "Unknown command mode response %2.2x\n",
                                            param[0]);
                }
        }

        return model;
}

/*
 * For DualPoint devices select the device that should respond to
 * subsequent commands. It looks like glidepad is behind stickpointer,
 * I'd thought it would be other way around...
 */
static int alps_passthrough_mode_v2(struct psmouse *psmouse, bool enable)
{
        struct ps2dev *ps2dev = &psmouse->ps2dev;
        int cmd = enable ? PSMOUSE_CMD_SETSCALE21 : PSMOUSE_CMD_SETSCALE11;

        if (ps2_command(ps2dev, NULL, cmd) ||
            ps2_command(ps2dev, NULL, cmd) ||
            ps2_command(ps2dev, NULL, cmd) ||
            ps2_command(ps2dev, NULL, PSMOUSE_CMD_DISABLE))
                return -1;

        /* we may get 3 more bytes, just ignore them */
        ps2_drain(ps2dev, 3, 100);

        return 0;
}

static int alps_absolute_mode_v1_v2(struct psmouse *psmouse)
{
        struct ps2dev *ps2dev = &psmouse->ps2dev;

        /* Try ALPS magic knock - 4 disable before enable */
        if (ps2_command(ps2dev, NULL, PSMOUSE_CMD_DISABLE) ||
            ps2_command(ps2dev, NULL, PSMOUSE_CMD_DISABLE) ||
            ps2_command(ps2dev, NULL, PSMOUSE_CMD_DISABLE) ||
            ps2_command(ps2dev, NULL, PSMOUSE_CMD_DISABLE) ||
            ps2_command(ps2dev, NULL, PSMOUSE_CMD_ENABLE))
                return -1;

        /*
         * Switch mouse to poll (remote) mode so motion data will not
         * get in our way
         */
        return ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_SETPOLL);
}

static int alps_get_status(struct psmouse *psmouse, char *param)
{
        struct ps2dev *ps2dev = &psmouse->ps2dev;

        /* Get status: 0xF5 0xF5 0xF5 0xE9 */
        if (ps2_command(ps2dev, NULL, PSMOUSE_CMD_DISABLE) ||
            ps2_command(ps2dev, NULL, PSMOUSE_CMD_DISABLE) ||
            ps2_command(ps2dev, NULL, PSMOUSE_CMD_DISABLE) ||
            ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO))
                return -1;

        psmouse_dbg(psmouse, "Status: %2.2x %2.2x %2.2x",
                    param[0], param[1], param[2]);

        return 0;
}

/*
 * Turn touchpad tapping on or off. The sequences are:
 * 0xE9 0xF5 0xF5 0xF3 0x0A to enable,
 * 0xE9 0xF5 0xF5 0xE8 0x00 to disable.
 * My guess that 0xE9 (GetInfo) is here as a sync point.
 * For models that also have stickpointer (DualPoints) its tapping
 * is controlled separately (0xE6 0xE6 0xE6 0xF3 0x14|0x0A) but
 * we don't fiddle with it.
 */
static int alps_tap_mode(struct psmouse *psmouse, int enable)
{
        struct ps2dev *ps2dev = &psmouse->ps2dev;
        int cmd = enable ? PSMOUSE_CMD_SETRATE : PSMOUSE_CMD_SETRES;
        unsigned char tap_arg = enable ? 0x0A : 0x00;
        unsigned char param[4];

        if (ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO) ||
            ps2_command(ps2dev, NULL, PSMOUSE_CMD_DISABLE) ||
            ps2_command(ps2dev, NULL, PSMOUSE_CMD_DISABLE) ||
            ps2_command(ps2dev, &tap_arg, cmd))
                return -1;

        if (alps_get_status(psmouse, param))
                return -1;

        return 0;
}

/*
 * alps_poll() - poll the touchpad for current motion packet.
 * Used in resync.
 */
static int alps_poll(struct psmouse *psmouse)
{
        struct alps_data *priv = psmouse->private;
        unsigned char buf[sizeof(psmouse->packet)];
        bool poll_failed;

        if (priv->i->flags & ALPS_PASS)
                alps_passthrough_mode_v2(psmouse, true);

        poll_failed = ps2_command(&psmouse->ps2dev, buf,
                                  PSMOUSE_CMD_POLL | (psmouse->pktsize << 8)) < 0;

        if (priv->i->flags & ALPS_PASS)
                alps_passthrough_mode_v2(psmouse, false);

        if (poll_failed || (buf[0] & priv->i->mask0) != priv->i->byte0)
                return -1;

        if ((psmouse->badbyte & 0xc8) == 0x08) {
/*
 * Poll the track stick ...
 */
                if (ps2_command(&psmouse->ps2dev, buf, PSMOUSE_CMD_POLL | (3 << 8)))
                        return -1;
        }

        memcpy(psmouse->packet, buf, sizeof(buf));
        return 0;
}

static int alps_hw_init_v1_v2(struct psmouse *psmouse)
{
        struct alps_data *priv = psmouse->private;
        const struct alps_model_info *model = priv->i;

        if ((model->flags & ALPS_PASS) &&
            alps_passthrough_mode_v2(psmouse, true)) {
                return -1;
        }

        if (alps_tap_mode(psmouse, true)) {
                psmouse_warn(psmouse, "Failed to enable hardware tapping\n");
                return -1;
        }

        if (alps_absolute_mode_v1_v2(psmouse)) {
                psmouse_err(psmouse, "Failed to enable absolute mode\n");
                return -1;
        }

        if ((model->flags & ALPS_PASS) &&
            alps_passthrough_mode_v2(psmouse, false)) {
                return -1;
        }

        /* ALPS needs stream mode, otherwise it won't report any data */
        if (ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_SETSTREAM)) {
                psmouse_err(psmouse, "Failed to enable stream mode\n");
                return -1;
        }

        return 0;
}

/*
 * Enable or disable passthrough mode to the trackstick. Must be in
 * command mode when calling this function.
 */
static int alps_passthrough_mode_v3(struct psmouse *psmouse, bool enable)
{
        int reg_val;

        reg_val = alps_command_mode_read_reg(psmouse, 0x0008);
        if (reg_val == -1)
                return -1;

        if (enable)
                reg_val |= 0x01;
        else
                reg_val &= ~0x01;

        if (__alps_command_mode_write_reg(psmouse, reg_val))
                return -1;

        return 0;
}

/* Must be in command mode when calling this function */
static int alps_absolute_mode_v3(struct psmouse *psmouse)
{
        int reg_val;

        reg_val = alps_command_mode_read_reg(psmouse, 0x0004);
        if (reg_val == -1)
                return -1;

        reg_val |= 0x06;
        if (__alps_command_mode_write_reg(psmouse, reg_val))
                return -1;

        return 0;
}

static int alps_hw_init_v3(struct psmouse *psmouse)
{
        struct alps_data *priv = psmouse->private;
        struct ps2dev *ps2dev = &psmouse->ps2dev;
        int reg_val;
        unsigned char param[4];

        priv->nibble_commands = alps_v3_nibble_commands;
        priv->addr_command = PSMOUSE_CMD_RESET_WRAP;

        if (alps_enter_command_mode(psmouse, NULL))
                goto error;

        /* Check for trackstick */
        reg_val = alps_command_mode_read_reg(psmouse, 0x0008);
        if (reg_val == -1)
                goto error;
        if (reg_val & 0x80) {
                if (alps_passthrough_mode_v3(psmouse, true))
                        goto error;
                if (alps_exit_command_mode(psmouse))
                        goto error;

                /*
                 * E7 report for the trackstick
                 *
                 * There have been reports of failures to seem to trace back
                 * to the above trackstick check failing. When these occur
                 * this E7 report fails, so when that happens we continue
                 * with the assumption that there isn't a trackstick after
                 * all.
                 */
                param[0] = 0x64;
                if (ps2_command(ps2dev, NULL, PSMOUSE_CMD_SETSCALE21) ||
                    ps2_command(ps2dev, NULL, PSMOUSE_CMD_SETSCALE21) ||
                    ps2_command(ps2dev, NULL, PSMOUSE_CMD_SETSCALE21) ||
                    ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO)) {
                        psmouse_warn(psmouse, "trackstick E7 report failed\n");
                } else {
                        psmouse_dbg(psmouse,
                                    "trackstick E7 report: %2.2x %2.2x %2.2x\n",
                                    param[0], param[1], param[2]);

                        /*
                         * Not sure what this does, but it is absolutely
                         * essential. Without it, the touchpad does not
                         * work at all and the trackstick just emits normal
                         * PS/2 packets.
                         */
                        if (ps2_command(ps2dev, NULL, PSMOUSE_CMD_SETSCALE11) ||
                            ps2_command(ps2dev, NULL, PSMOUSE_CMD_SETSCALE11) ||
                            ps2_command(ps2dev, NULL, PSMOUSE_CMD_SETSCALE11) ||
                            alps_command_mode_send_nibble(psmouse, 0x9) ||
                            alps_command_mode_send_nibble(psmouse, 0x4)) {
                                psmouse_err(psmouse,
                                            "Error sending magic E6 sequence\n");
                                goto error_passthrough;
                        }
                }

                if (alps_enter_command_mode(psmouse, NULL))
                        goto error_passthrough;
                if (alps_passthrough_mode_v3(psmouse, false))
                        goto error;
        }

        if (alps_absolute_mode_v3(psmouse)) {
                psmouse_err(psmouse, "Failed to enter absolute mode\n");
                goto error;
        }

        reg_val = alps_command_mode_read_reg(psmouse, 0x0006);
        if (reg_val == -1)
                goto error;
        if (__alps_command_mode_write_reg(psmouse, reg_val | 0x01))
                goto error;

        reg_val = alps_command_mode_read_reg(psmouse, 0x0007);
        if (reg_val == -1)
                goto error;
        if (__alps_command_mode_write_reg(psmouse, reg_val | 0x01))
                goto error;

        if (alps_command_mode_read_reg(psmouse, 0x0144) == -1)
                goto error;
        if (__alps_command_mode_write_reg(psmouse, 0x04))
                goto error;

        if (alps_command_mode_read_reg(psmouse, 0x0159) == -1)
                goto error;
        if (__alps_command_mode_write_reg(psmouse, 0x03))
                goto error;

        if (alps_command_mode_read_reg(psmouse, 0x0163) == -1)
                goto error;
        if (alps_command_mode_write_reg(psmouse, 0x0163, 0x03))
                goto error;

        if (alps_command_mode_read_reg(psmouse, 0x0162) == -1)
                goto error;
        if (alps_command_mode_write_reg(psmouse, 0x0162, 0x04))
                goto error;

        /*
         * This ensures the trackstick packets are in the format
         * supported by this driver. If bit 1 isn't set the packet
         * format is different.
         */
        if (alps_command_mode_write_reg(psmouse, 0x0008, 0x82))
                goto error;

        alps_exit_command_mode(psmouse);

        /* Set rate and enable data reporting */
        param[0] = 0x64;
        if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE) ||
            ps2_command(ps2dev, NULL, PSMOUSE_CMD_ENABLE)) {
                psmouse_err(psmouse, "Failed to enable data reporting\n");
                return -1;
        }

        return 0;

error_passthrough:
        /* Something failed while in passthrough mode, so try to get out */
        if (!alps_enter_command_mode(psmouse, NULL))
                alps_passthrough_mode_v3(psmouse, false);
error:
        /*
         * Leaving the touchpad in command mode will essentially render
         * it unusable until the machine reboots, so exit it here just
         * to be safe
         */
        alps_exit_command_mode(psmouse);
        return -1;
}

/* Must be in command mode when calling this function */
static int alps_absolute_mode_v4(struct psmouse *psmouse)
{
        int reg_val;

        reg_val = alps_command_mode_read_reg(psmouse, 0x0004);
        if (reg_val == -1)
                return -1;

        reg_val |= 0x02;
        if (__alps_command_mode_write_reg(psmouse, reg_val))
                return -1;

        return 0;
}

static int alps_hw_init_v4(struct psmouse *psmouse)
{
        struct alps_data *priv = psmouse->private;
        struct ps2dev *ps2dev = &psmouse->ps2dev;
        unsigned char param[4];

        priv->nibble_commands = alps_v4_nibble_commands;
        priv->addr_command = PSMOUSE_CMD_DISABLE;

        if (alps_enter_command_mode(psmouse, NULL))
                goto error;

        if (alps_absolute_mode_v4(psmouse)) {
                psmouse_err(psmouse, "Failed to enter absolute mode\n");
                goto error;
        }

        if (alps_command_mode_write_reg(psmouse, 0x0007, 0x8c))
                goto error;

        if (alps_command_mode_write_reg(psmouse, 0x0149, 0x03))
                goto error;

        if (alps_command_mode_write_reg(psmouse, 0x0160, 0x03))
                goto error;

        if (alps_command_mode_write_reg(psmouse, 0x017f, 0x15))
                goto error;

        if (alps_command_mode_write_reg(psmouse, 0x0151, 0x01))
                goto error;

        if (alps_command_mode_write_reg(psmouse, 0x0168, 0x03))
                goto error;

        if (alps_command_mode_write_reg(psmouse, 0x014a, 0x03))
                goto error;

        if (alps_command_mode_write_reg(psmouse, 0x0161, 0x03))
                goto error;

        alps_exit_command_mode(psmouse);

        /*
         * This sequence changes the output from a 9-byte to an
         * 8-byte format. All the same data seems to be present,
         * just in a more compact format.
         */
        param[0] = 0xc8;
        param[1] = 0x64;
        param[2] = 0x50;
        if (ps2_command(ps2dev, &param[0], PSMOUSE_CMD_SETRATE) ||
            ps2_command(ps2dev, &param[1], PSMOUSE_CMD_SETRATE) ||
            ps2_command(ps2dev, &param[2], PSMOUSE_CMD_SETRATE) ||
            ps2_command(ps2dev, param, PSMOUSE_CMD_GETID))
                return -1;

        /* Set rate and enable data reporting */
        param[0] = 0x64;
        if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE) ||
            ps2_command(ps2dev, NULL, PSMOUSE_CMD_ENABLE)) {
                psmouse_err(psmouse, "Failed to enable data reporting\n");
                return -1;
        }

        return 0;

error:
        /*
         * Leaving the touchpad in command mode will essentially render
         * it unusable until the machine reboots, so exit it here just
         * to be safe
         */
        alps_exit_command_mode(psmouse);
        return -1;
}

static int alps_hw_init(struct psmouse *psmouse)
{
        struct alps_data *priv = psmouse->private;
        const struct alps_model_info *model = priv->i;
        int ret = -1;

        switch (model->proto_version) {
        case ALPS_PROTO_V1:
        case ALPS_PROTO_V2:
                ret = alps_hw_init_v1_v2(psmouse);
                break;
        case ALPS_PROTO_V3:
                ret = alps_hw_init_v3(psmouse);
                break;
        case ALPS_PROTO_V4:
                ret = alps_hw_init_v4(psmouse);
                break;
        }

        return ret;
}

static int alps_reconnect(struct psmouse *psmouse)
{
        const struct alps_model_info *model;

        psmouse_reset(psmouse);

        model = alps_get_model(psmouse, NULL);
        if (!model)
                return -1;

        return alps_hw_init(psmouse);
}

static void alps_disconnect(struct psmouse *psmouse)
{
        struct alps_data *priv = psmouse->private;

        psmouse_reset(psmouse);
        del_timer_sync(&priv->timer);
        input_unregister_device(priv->dev2);
        kfree(priv);
}

int alps_init(struct psmouse *psmouse)
{
        struct alps_data *priv;
        const struct alps_model_info *model;
        struct input_dev *dev1 = psmouse->dev, *dev2;
        int version;

        priv = kzalloc(sizeof(struct alps_data), GFP_KERNEL);
        dev2 = input_allocate_device();
        if (!priv || !dev2)
                goto init_fail;

        priv->dev2 = dev2;
        setup_timer(&priv->timer, alps_flush_packet, (unsigned long)psmouse);

        psmouse->private = priv;

        psmouse_reset(psmouse);

        model = alps_get_model(psmouse, &version);
        if (!model)
                goto init_fail;

        priv->i = model;

        if (alps_hw_init(psmouse))
                goto init_fail;

        /*
         * Undo part of setup done for us by psmouse core since touchpad
         * is not a relative device.
         */
        __clear_bit(EV_REL, dev1->evbit);
        __clear_bit(REL_X, dev1->relbit);
        __clear_bit(REL_Y, dev1->relbit);

        /*
         * Now set up our capabilities.
         */
        dev1->evbit[BIT_WORD(EV_KEY)] |= BIT_MASK(EV_KEY);
        dev1->keybit[BIT_WORD(BTN_TOUCH)] |= BIT_MASK(BTN_TOUCH);
        dev1->keybit[BIT_WORD(BTN_TOOL_FINGER)] |= BIT_MASK(BTN_TOOL_FINGER);
        dev1->keybit[BIT_WORD(BTN_LEFT)] |=
                BIT_MASK(BTN_LEFT) | BIT_MASK(BTN_RIGHT);

        dev1->evbit[BIT_WORD(EV_ABS)] |= BIT_MASK(EV_ABS);

        switch (model->proto_version) {
        case ALPS_PROTO_V1:
        case ALPS_PROTO_V2:
                input_set_abs_params(dev1, ABS_X, 0, 1023, 0, 0);
                input_set_abs_params(dev1, ABS_Y, 0, 767, 0, 0);
                break;
        case ALPS_PROTO_V3:
        case ALPS_PROTO_V4:
                set_bit(INPUT_PROP_SEMI_MT, dev1->propbit);
                input_mt_init_slots(dev1, 2);
                input_set_abs_params(dev1, ABS_MT_POSITION_X, 0, ALPS_V3_X_MAX, 0, 0);
                input_set_abs_params(dev1, ABS_MT_POSITION_Y, 0, ALPS_V3_Y_MAX, 0, 0);

                set_bit(BTN_TOOL_DOUBLETAP, dev1->keybit);
                set_bit(BTN_TOOL_TRIPLETAP, dev1->keybit);
                set_bit(BTN_TOOL_QUADTAP, dev1->keybit);

                input_set_abs_params(dev1, ABS_X, 0, ALPS_V3_X_MAX, 0, 0);
                input_set_abs_params(dev1, ABS_Y, 0, ALPS_V3_Y_MAX, 0, 0);
                break;
        }

        input_set_abs_params(dev1, ABS_PRESSURE, 0, 127, 0, 0);

        if (model->flags & ALPS_WHEEL) {
                dev1->evbit[BIT_WORD(EV_REL)] |= BIT_MASK(EV_REL);
                dev1->relbit[BIT_WORD(REL_WHEEL)] |= BIT_MASK(REL_WHEEL);
        }

        if (model->flags & (ALPS_FW_BK_1 | ALPS_FW_BK_2)) {
                dev1->keybit[BIT_WORD(BTN_FORWARD)] |= BIT_MASK(BTN_FORWARD);
                dev1->keybit[BIT_WORD(BTN_BACK)] |= BIT_MASK(BTN_BACK);
        }

        if (model->flags & ALPS_FOUR_BUTTONS) {
                dev1->keybit[BIT_WORD(BTN_0)] |= BIT_MASK(BTN_0);
                dev1->keybit[BIT_WORD(BTN_1)] |= BIT_MASK(BTN_1);
                dev1->keybit[BIT_WORD(BTN_2)] |= BIT_MASK(BTN_2);
                dev1->keybit[BIT_WORD(BTN_3)] |= BIT_MASK(BTN_3);
        } else {
                dev1->keybit[BIT_WORD(BTN_MIDDLE)] |= BIT_MASK(BTN_MIDDLE);
        }

        snprintf(priv->phys, sizeof(priv->phys), "%s/input1", psmouse->ps2dev.serio->phys);
        dev2->phys = priv->phys;
        dev2->name = (model->flags & ALPS_DUALPOINT) ? "DualPoint Stick" : "PS/2 Mouse";
        dev2->id.bustype = BUS_I8042;
        dev2->id.vendor  = 0x0002;
        dev2->id.product = PSMOUSE_ALPS;
        dev2->id.version = 0x0000;
        dev2->dev.parent = &psmouse->ps2dev.serio->dev;

        dev2->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REL);
        dev2->relbit[BIT_WORD(REL_X)] = BIT_MASK(REL_X) | BIT_MASK(REL_Y);
        dev2->keybit[BIT_WORD(BTN_LEFT)] =
                BIT_MASK(BTN_LEFT) | BIT_MASK(BTN_MIDDLE) | BIT_MASK(BTN_RIGHT);

        if (input_register_device(priv->dev2))
                goto init_fail;

        psmouse->protocol_handler = alps_process_byte;
        psmouse->poll = alps_poll;
        psmouse->disconnect = alps_disconnect;
        psmouse->reconnect = alps_reconnect;
        psmouse->pktsize = model->proto_version == ALPS_PROTO_V4 ? 8 : 6;

        /* We are having trouble resyncing ALPS touchpads so disable it for now */
        psmouse->resync_time = 0;

        return 0;

init_fail:
        psmouse_reset(psmouse);
        input_free_device(dev2);
        kfree(priv);
        psmouse->private = NULL;
        return -1;
}

int alps_detect(struct psmouse *psmouse, bool set_properties)
{
        int version;
        const struct alps_model_info *model;

        model = alps_get_model(psmouse, &version);
        if (!model)
                return -1;

        if (set_properties) {
                psmouse->vendor = "ALPS";
                psmouse->name = model->flags & ALPS_DUALPOINT ?
                                "DualPoint TouchPad" : "GlidePoint";
                psmouse->model = version;
        }
        return 0;
}