psmouse-base.c

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/*
 * PS/2 mouse driver
 *
 * Copyright (c) 1999-2002 Vojtech Pavlik
 * Copyright (c) 2003-2004 Dmitry Torokhov
 */

/*
 * 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.
 */

#define pr_fmt(fmt)     KBUILD_MODNAME ": " fmt
#define psmouse_fmt(fmt)    fmt

#include <linux/delay.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/input.h>
#include <linux/serio.h>
#include <linux/init.h>
#include <linux/libps2.h>
#include <linux/mutex.h>

#include "psmouse.h"
#include "synaptics.h"
#include "logips2pp.h"
#include "alps.h"
#include "hgpk.h"
#include "lifebook.h"
#include "trackpoint.h"
#include "touchkit_ps2.h"
#include "elantech.h"
#include "sentelic.h"

#define DRIVER_DESC "PS/2 mouse driver"

MODULE_AUTHOR("Vojtech Pavlik <[email protected]>");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");

static unsigned int psmouse_max_proto = PSMOUSE_AUTO;
static int psmouse_set_maxproto(const char *val, const struct kernel_param *);
static int psmouse_get_maxproto(char *buffer, const struct kernel_param *kp);
static struct kernel_param_ops param_ops_proto_abbrev = {
    .set = psmouse_set_maxproto,
    .get = psmouse_get_maxproto,
};
#define param_check_proto_abbrev(name, p)   __param_check(name, p, unsigned int)
module_param_named(proto, psmouse_max_proto, proto_abbrev, 0644);
MODULE_PARM_DESC(proto, "Highest protocol extension to probe (bare, imps, exps, any). Useful for KVM switches.");

static unsigned int psmouse_resolution = 200;
module_param_named(resolution, psmouse_resolution, uint, 0644);
MODULE_PARM_DESC(resolution, "Resolution, in dpi.");

static unsigned int psmouse_rate = 100;
module_param_named(rate, psmouse_rate, uint, 0644);
MODULE_PARM_DESC(rate, "Report rate, in reports per second.");

static bool psmouse_smartscroll = 1;
module_param_named(smartscroll, psmouse_smartscroll, bool, 0644);
MODULE_PARM_DESC(smartscroll, "Logitech Smartscroll autorepeat, 1 = enabled (default), 0 = disabled.");

static unsigned int psmouse_resetafter = 5;
module_param_named(resetafter, psmouse_resetafter, uint, 0644);
MODULE_PARM_DESC(resetafter, "Reset device after so many bad packets (0 = never).");

static unsigned int psmouse_resync_time;
module_param_named(resync_time, psmouse_resync_time, uint, 0644);
MODULE_PARM_DESC(resync_time, "How long can mouse stay idle before forcing resync (in seconds, 0 = never).");

PSMOUSE_DEFINE_ATTR(protocol, S_IWUSR | S_IRUGO,
            NULL,
            psmouse_attr_show_protocol, psmouse_attr_set_protocol);
PSMOUSE_DEFINE_ATTR(rate, S_IWUSR | S_IRUGO,
            (void *) offsetof(struct psmouse, rate),
            psmouse_show_int_attr, psmouse_attr_set_rate);
PSMOUSE_DEFINE_ATTR(resolution, S_IWUSR | S_IRUGO,
            (void *) offsetof(struct psmouse, resolution),
            psmouse_show_int_attr, psmouse_attr_set_resolution);
PSMOUSE_DEFINE_ATTR(resetafter, S_IWUSR | S_IRUGO,
            (void *) offsetof(struct psmouse, resetafter),
            psmouse_show_int_attr, psmouse_set_int_attr);
PSMOUSE_DEFINE_ATTR(resync_time, S_IWUSR | S_IRUGO,
            (void *) offsetof(struct psmouse, resync_time),
            psmouse_show_int_attr, psmouse_set_int_attr);

static struct attribute *psmouse_attributes[] = {
    &psmouse_attr_protocol.dattr.attr,
    &psmouse_attr_rate.dattr.attr,
    &psmouse_attr_resolution.dattr.attr,
    &psmouse_attr_resetafter.dattr.attr,
    &psmouse_attr_resync_time.dattr.attr,
    NULL
};

static struct attribute_group psmouse_attribute_group = {
    .attrs  = psmouse_attributes,
};

/*
 * psmouse_mutex protects all operations changing state of mouse
 * (connecting, disconnecting, changing rate or resolution via
 * sysfs). We could use a per-device semaphore but since there
 * rarely more than one PS/2 mouse connected and since semaphore
 * is taken in "slow" paths it is not worth it.
 */
static DEFINE_MUTEX(psmouse_mutex);

static struct workqueue_struct *kpsmoused_wq;

struct psmouse_protocol {
    enum psmouse_type type;
    bool maxproto;
    bool ignore_parity; /* Protocol should ignore parity errors from KBC */
    const char *name;
    const char *alias;
    int (*detect)(struct psmouse *, bool);
    int (*init)(struct psmouse *);
};

/*
 * psmouse_process_byte() analyzes the PS/2 data stream and reports
 * relevant events to the input module once full packet has arrived.
 */

psmouse_ret_t psmouse_process_byte(struct psmouse *psmouse)
{
    struct input_dev *dev = psmouse->dev;
    unsigned char *packet = psmouse->packet;

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

/*
 * Full packet accumulated, process it
 */

/*
 * Scroll wheel on IntelliMice, scroll buttons on NetMice
 */

    if (psmouse->type == PSMOUSE_IMPS || psmouse->type == PSMOUSE_GENPS)
        input_report_rel(dev, REL_WHEEL, -(signed char) packet[3]);

/*
 * Scroll wheel and buttons on IntelliMouse Explorer
 */

    if (psmouse->type == PSMOUSE_IMEX) {
        switch (packet[3] & 0xC0) {
        case 0x80: /* vertical scroll on IntelliMouse Explorer 4.0 */
            input_report_rel(dev, REL_WHEEL, (int) (packet[3] & 32) - (int) (packet[3] & 31));
            break;
        case 0x40: /* horizontal scroll on IntelliMouse Explorer 4.0 */
            input_report_rel(dev, REL_HWHEEL, (int) (packet[3] & 32) - (int) (packet[3] & 31));
            break;
        case 0x00:
        case 0xC0:
            input_report_rel(dev, REL_WHEEL, (int) (packet[3] & 8) - (int) (packet[3] & 7));
            input_report_key(dev, BTN_SIDE, (packet[3] >> 4) & 1);
            input_report_key(dev, BTN_EXTRA, (packet[3] >> 5) & 1);
            break;
        }
    }

/*
 * Extra buttons on Genius NewNet 3D
 */

    if (psmouse->type == PSMOUSE_GENPS) {
        input_report_key(dev, BTN_SIDE, (packet[0] >> 6) & 1);
        input_report_key(dev, BTN_EXTRA, (packet[0] >> 7) & 1);
    }

/*
 * Extra button on ThinkingMouse
 */
    if (psmouse->type == PSMOUSE_THINKPS) {
        input_report_key(dev, BTN_EXTRA, (packet[0] >> 3) & 1);
        /* Without this bit of weirdness moving up gives wildly high Y changes. */
        packet[1] |= (packet[0] & 0x40) << 1;
    }

/*
 * Cortron PS2 Trackball reports SIDE button on the 4th bit of the first
 * byte.
 */
    if (psmouse->type == PSMOUSE_CORTRON) {
        input_report_key(dev, BTN_SIDE, (packet[0] >> 3) & 1);
        packet[0] |= 0x08;
    }

/*
 * Generic PS/2 Mouse
 */

    input_report_key(dev, BTN_LEFT,    packet[0]       & 1);
    input_report_key(dev, BTN_MIDDLE, (packet[0] >> 2) & 1);
    input_report_key(dev, BTN_RIGHT,  (packet[0] >> 1) & 1);

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

    input_sync(dev);

    return PSMOUSE_FULL_PACKET;
}

void psmouse_queue_work(struct psmouse *psmouse, struct delayed_work *work,
        unsigned long delay)
{
    queue_delayed_work(kpsmoused_wq, work, delay);
}

/*
 * __psmouse_set_state() sets new psmouse state and resets all flags.
 */

static inline void __psmouse_set_state(struct psmouse *psmouse, enum psmouse_state new_state)
{
    psmouse->state = new_state;
    psmouse->pktcnt = psmouse->out_of_sync_cnt = 0;
    psmouse->ps2dev.flags = 0;
    psmouse->last = jiffies;
}


/*
 * psmouse_set_state() sets new psmouse state and resets all flags and
 * counters while holding serio lock so fighting with interrupt handler
 * is not a concern.
 */

void psmouse_set_state(struct psmouse *psmouse, enum psmouse_state new_state)
{
    serio_pause_rx(psmouse->ps2dev.serio);
    __psmouse_set_state(psmouse, new_state);
    serio_continue_rx(psmouse->ps2dev.serio);
}

/*
 * psmouse_handle_byte() processes one byte of the input data stream
 * by calling corresponding protocol handler.
 */

static int psmouse_handle_byte(struct psmouse *psmouse)
{
    psmouse_ret_t rc = psmouse->protocol_handler(psmouse);

    switch (rc) {
    case PSMOUSE_BAD_DATA:
        if (psmouse->state == PSMOUSE_ACTIVATED) {
            psmouse_warn(psmouse,
                     "%s at %s lost sync at byte %d\n",
                     psmouse->name, psmouse->phys,
                     psmouse->pktcnt);
            if (++psmouse->out_of_sync_cnt == psmouse->resetafter) {
                __psmouse_set_state(psmouse, PSMOUSE_IGNORE);
                psmouse_notice(psmouse,
                        "issuing reconnect request\n");
                serio_reconnect(psmouse->ps2dev.serio);
                return -1;
            }
        }
        psmouse->pktcnt = 0;
        break;

    case PSMOUSE_FULL_PACKET:
        psmouse->pktcnt = 0;
        if (psmouse->out_of_sync_cnt) {
            psmouse->out_of_sync_cnt = 0;
            psmouse_notice(psmouse,
                    "%s at %s - driver resynced.\n",
                    psmouse->name, psmouse->phys);
        }
        break;

    case PSMOUSE_GOOD_DATA:
        break;
    }
    return 0;
}

/*
 * psmouse_interrupt() handles incoming characters, either passing them
 * for normal processing or gathering them as command response.
 */

static irqreturn_t psmouse_interrupt(struct serio *serio,
        unsigned char data, unsigned int flags)
{
    struct psmouse *psmouse = serio_get_drvdata(serio);

    if (psmouse->state == PSMOUSE_IGNORE)
        goto out;

    if (unlikely((flags & SERIO_TIMEOUT) ||
             ((flags & SERIO_PARITY) && !psmouse->ignore_parity))) {

        if (psmouse->state == PSMOUSE_ACTIVATED)
            psmouse_warn(psmouse,
                     "bad data from KBC -%s%s\n",
                     flags & SERIO_TIMEOUT ? " timeout" : "",
                     flags & SERIO_PARITY ? " bad parity" : "");
        ps2_cmd_aborted(&psmouse->ps2dev);
        goto out;
    }

    if (unlikely(psmouse->ps2dev.flags & PS2_FLAG_ACK))
        if  (ps2_handle_ack(&psmouse->ps2dev, data))
            goto out;

    if (unlikely(psmouse->ps2dev.flags & PS2_FLAG_CMD))
        if  (ps2_handle_response(&psmouse->ps2dev, data))
            goto out;

    if (psmouse->state <= PSMOUSE_RESYNCING)
        goto out;

    if (psmouse->state == PSMOUSE_ACTIVATED &&
        psmouse->pktcnt && time_after(jiffies, psmouse->last + HZ/2)) {
        psmouse_info(psmouse, "%s at %s lost synchronization, throwing %d bytes away.\n",
                 psmouse->name, psmouse->phys, psmouse->pktcnt);
        psmouse->badbyte = psmouse->packet[0];
        __psmouse_set_state(psmouse, PSMOUSE_RESYNCING);
        psmouse_queue_work(psmouse, &psmouse->resync_work, 0);
        goto out;
    }

    psmouse->packet[psmouse->pktcnt++] = data;
/*
 * Check if this is a new device announcement (0xAA 0x00)
 */
    if (unlikely(psmouse->packet[0] == PSMOUSE_RET_BAT && psmouse->pktcnt <= 2)) {
        if (psmouse->pktcnt == 1) {
            psmouse->last = jiffies;
            goto out;
        }

        if (psmouse->packet[1] == PSMOUSE_RET_ID ||
            (psmouse->type == PSMOUSE_HGPK &&
             psmouse->packet[1] == PSMOUSE_RET_BAT)) {
            __psmouse_set_state(psmouse, PSMOUSE_IGNORE);
            serio_reconnect(serio);
            goto out;
        }
/*
 * Not a new device, try processing first byte normally
 */
        psmouse->pktcnt = 1;
        if (psmouse_handle_byte(psmouse))
            goto out;

        psmouse->packet[psmouse->pktcnt++] = data;
    }

/*
 * See if we need to force resync because mouse was idle for too long
 */
    if (psmouse->state == PSMOUSE_ACTIVATED &&
        psmouse->pktcnt == 1 && psmouse->resync_time &&
        time_after(jiffies, psmouse->last + psmouse->resync_time * HZ)) {
        psmouse->badbyte = psmouse->packet[0];
        __psmouse_set_state(psmouse, PSMOUSE_RESYNCING);
        psmouse_queue_work(psmouse, &psmouse->resync_work, 0);
        goto out;
    }

    psmouse->last = jiffies;
    psmouse_handle_byte(psmouse);

 out:
    return IRQ_HANDLED;
}


/*
 * psmouse_sliced_command() sends an extended PS/2 command to the mouse
 * using sliced syntax, understood by advanced devices, such as Logitech
 * or Synaptics touchpads. The command is encoded as:
 * 0xE6 0xE8 rr 0xE8 ss 0xE8 tt 0xE8 uu where (rr*64)+(ss*16)+(tt*4)+uu
 * is the command.
 */
int psmouse_sliced_command(struct psmouse *psmouse, unsigned char command)
{
    int i;

    if (ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_SETSCALE11))
        return -1;

    for (i = 6; i >= 0; i -= 2) {
        unsigned char d = (command >> i) & 3;
        if (ps2_command(&psmouse->ps2dev, &d, PSMOUSE_CMD_SETRES))
            return -1;
    }

    return 0;
}


/*
 * psmouse_reset() resets the mouse into power-on state.
 */
int psmouse_reset(struct psmouse *psmouse)
{
    unsigned char param[2];

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

    if (param[0] != PSMOUSE_RET_BAT && param[1] != PSMOUSE_RET_ID)
        return -1;

    return 0;
}

/*
 * Here we set the mouse resolution.
 */

void psmouse_set_resolution(struct psmouse *psmouse, unsigned int resolution)
{
    static const unsigned char params[] = { 0, 1, 2, 2, 3 };
    unsigned char p;

    if (resolution == 0 || resolution > 200)
        resolution = 200;

    p = params[resolution / 50];
    ps2_command(&psmouse->ps2dev, &p, PSMOUSE_CMD_SETRES);
    psmouse->resolution = 25 << p;
}

/*
 * Here we set the mouse report rate.
 */

static void psmouse_set_rate(struct psmouse *psmouse, unsigned int rate)
{
    static const unsigned char rates[] = { 200, 100, 80, 60, 40, 20, 10, 0 };
    unsigned char r;
    int i = 0;

    while (rates[i] > rate) i++;
    r = rates[i];
    ps2_command(&psmouse->ps2dev, &r, PSMOUSE_CMD_SETRATE);
    psmouse->rate = r;
}

/*
 * psmouse_poll() - default poll handler. Everyone except for ALPS uses it.
 */

static int psmouse_poll(struct psmouse *psmouse)
{
    return ps2_command(&psmouse->ps2dev, psmouse->packet,
               PSMOUSE_CMD_POLL | (psmouse->pktsize << 8));
}


/*
 * Genius NetMouse magic init.
 */
static int genius_detect(struct psmouse *psmouse, bool set_properties)
{
    struct ps2dev *ps2dev = &psmouse->ps2dev;
    unsigned char param[4];

    param[0] = 3;
    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);
    ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO);

    if (param[0] != 0x00 || param[1] != 0x33 || param[2] != 0x55)
        return -1;

    if (set_properties) {
        __set_bit(BTN_MIDDLE, psmouse->dev->keybit);
        __set_bit(BTN_EXTRA, psmouse->dev->keybit);
        __set_bit(BTN_SIDE, psmouse->dev->keybit);
        __set_bit(REL_WHEEL, psmouse->dev->relbit);

        psmouse->vendor = "Genius";
        psmouse->name = "Mouse";
        psmouse->pktsize = 4;
    }

    return 0;
}

/*
 * IntelliMouse magic init.
 */
static int intellimouse_detect(struct psmouse *psmouse, bool set_properties)
{
    struct ps2dev *ps2dev = &psmouse->ps2dev;
    unsigned char param[2];

    param[0] = 200;
    ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
    param[0] = 100;
    ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
    param[0] =  80;
    ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
    ps2_command(ps2dev, param, PSMOUSE_CMD_GETID);

    if (param[0] != 3)
        return -1;

    if (set_properties) {
        __set_bit(BTN_MIDDLE, psmouse->dev->keybit);
        __set_bit(REL_WHEEL, psmouse->dev->relbit);

        if (!psmouse->vendor)
            psmouse->vendor = "Generic";
        if (!psmouse->name)
            psmouse->name = "Wheel Mouse";
        psmouse->pktsize = 4;
    }

    return 0;
}

/*
 * Try IntelliMouse/Explorer magic init.
 */
static int im_explorer_detect(struct psmouse *psmouse, bool set_properties)
{
    struct ps2dev *ps2dev = &psmouse->ps2dev;
    unsigned char param[2];

    intellimouse_detect(psmouse, 0);

    param[0] = 200;
    ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
    param[0] = 200;
    ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
    param[0] =  80;
    ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
    ps2_command(ps2dev, param, PSMOUSE_CMD_GETID);

    if (param[0] != 4)
        return -1;

/* Magic to enable horizontal scrolling on IntelliMouse 4.0 */
    param[0] = 200;
    ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
    param[0] =  80;
    ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
    param[0] =  40;
    ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);

    if (set_properties) {
        __set_bit(BTN_MIDDLE, psmouse->dev->keybit);
        __set_bit(REL_WHEEL, psmouse->dev->relbit);
        __set_bit(REL_HWHEEL, psmouse->dev->relbit);
        __set_bit(BTN_SIDE, psmouse->dev->keybit);
        __set_bit(BTN_EXTRA, psmouse->dev->keybit);

        if (!psmouse->vendor)
            psmouse->vendor = "Generic";
        if (!psmouse->name)
            psmouse->name = "Explorer Mouse";
        psmouse->pktsize = 4;
    }

    return 0;
}

/*
 * Kensington ThinkingMouse / ExpertMouse magic init.
 */
static int thinking_detect(struct psmouse *psmouse, bool set_properties)
{
    struct ps2dev *ps2dev = &psmouse->ps2dev;
    unsigned char param[2];
    static const unsigned char seq[] = { 20, 60, 40, 20, 20, 60, 40, 20, 20 };
    int i;

    param[0] = 10;
    ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
    param[0] = 0;
    ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES);
    for (i = 0; i < ARRAY_SIZE(seq); i++) {
        param[0] = seq[i];
        ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
    }
    ps2_command(ps2dev, param, PSMOUSE_CMD_GETID);

    if (param[0] != 2)
        return -1;

    if (set_properties) {
        __set_bit(BTN_MIDDLE, psmouse->dev->keybit);
        __set_bit(BTN_EXTRA, psmouse->dev->keybit);

        psmouse->vendor = "Kensington";
        psmouse->name = "ThinkingMouse";
    }

    return 0;
}

/*
 * Bare PS/2 protocol "detection". Always succeeds.
 */
static int ps2bare_detect(struct psmouse *psmouse, bool set_properties)
{
    if (set_properties) {
        if (!psmouse->vendor)
            psmouse->vendor = "Generic";
        if (!psmouse->name)
            psmouse->name = "Mouse";

/*
 * We have no way of figuring true number of buttons so let's
 * assume that the device has 3.
 */
        __set_bit(BTN_MIDDLE, psmouse->dev->keybit);
    }

    return 0;
}

/*
 * Cortron PS/2 protocol detection. There's no special way to detect it, so it
 * must be forced by sysfs protocol writing.
 */
static int cortron_detect(struct psmouse *psmouse, bool set_properties)
{
    if (set_properties) {
        psmouse->vendor = "Cortron";
        psmouse->name = "PS/2 Trackball";

        __set_bit(BTN_MIDDLE, psmouse->dev->keybit);
        __set_bit(BTN_SIDE, psmouse->dev->keybit);
    }

    return 0;
}

/*
 * Apply default settings to the psmouse structure. Most of them will
 * be overridden by individual protocol initialization routines.
 */

static void psmouse_apply_defaults(struct psmouse *psmouse)
{
    struct input_dev *input_dev = psmouse->dev;

    memset(input_dev->evbit, 0, sizeof(input_dev->evbit));
    memset(input_dev->keybit, 0, sizeof(input_dev->keybit));
    memset(input_dev->relbit, 0, sizeof(input_dev->relbit));
    memset(input_dev->absbit, 0, sizeof(input_dev->absbit));
    memset(input_dev->mscbit, 0, sizeof(input_dev->mscbit));

    __set_bit(EV_KEY, input_dev->evbit);
    __set_bit(EV_REL, input_dev->evbit);

    __set_bit(BTN_LEFT, input_dev->keybit);
    __set_bit(BTN_RIGHT, input_dev->keybit);

    __set_bit(REL_X, input_dev->relbit);
    __set_bit(REL_Y, input_dev->relbit);

    psmouse->set_rate = psmouse_set_rate;
    psmouse->set_resolution = psmouse_set_resolution;
    psmouse->poll = psmouse_poll;
    psmouse->protocol_handler = psmouse_process_byte;
    psmouse->pktsize = 3;
    psmouse->reconnect = NULL;
    psmouse->disconnect = NULL;
    psmouse->cleanup = NULL;
    psmouse->pt_activate = NULL;
    psmouse->pt_deactivate = NULL;
}

/*
 * Apply default settings to the psmouse structure and call specified
 * protocol detection or initialization routine.
 */
static int psmouse_do_detect(int (*detect)(struct psmouse *psmouse,
                       bool set_properties),
                 struct psmouse *psmouse, bool set_properties)
{
    if (set_properties)
        psmouse_apply_defaults(psmouse);

    return detect(psmouse, set_properties);
}

/*
 * psmouse_extensions() probes for any extensions to the basic PS/2 protocol
 * the mouse may have.
 */

static int psmouse_extensions(struct psmouse *psmouse,
                  unsigned int max_proto, bool set_properties)
{
    bool synaptics_hardware = false;

/*
 * We always check for lifebook because it does not disturb mouse
 * (it only checks DMI information).
 */
    if (psmouse_do_detect(lifebook_detect, psmouse, set_properties) == 0) {
        if (max_proto > PSMOUSE_IMEX) {
            if (!set_properties || lifebook_init(psmouse) == 0)
                return PSMOUSE_LIFEBOOK;
        }
    }

/*
 * Try Kensington ThinkingMouse (we try first, because synaptics probe
 * upsets the thinkingmouse).
 */

    if (max_proto > PSMOUSE_IMEX &&
        psmouse_do_detect(thinking_detect, psmouse, set_properties) == 0) {
        return PSMOUSE_THINKPS;
    }

/*
 * Try Synaptics TouchPad. Note that probing is done even if Synaptics protocol
 * support is disabled in config - we need to know if it is synaptics so we
 * can reset it properly after probing for intellimouse.
 */
    if (max_proto > PSMOUSE_PS2 &&
        psmouse_do_detect(synaptics_detect, psmouse, set_properties) == 0) {
        synaptics_hardware = true;

        if (max_proto > PSMOUSE_IMEX) {
/*
 * Try activating protocol, but check if support is enabled first, since
 * we try detecting Synaptics even when protocol is disabled.
 */
            if (synaptics_supported() &&
                (!set_properties || synaptics_init(psmouse) == 0)) {
                return PSMOUSE_SYNAPTICS;
            }

/*
 * Some Synaptics touchpads can emulate extended protocols (like IMPS/2).
 * Unfortunately Logitech/Genius probes confuse some firmware versions so
 * we'll have to skip them.
 */
            max_proto = PSMOUSE_IMEX;
        }
/*
 * Make sure that touchpad is in relative mode, gestures (taps) are enabled
 */
        synaptics_reset(psmouse);
    }

/*
 * Try ALPS TouchPad
 */
    if (max_proto > PSMOUSE_IMEX) {
        ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_RESET_DIS);
        if (psmouse_do_detect(alps_detect,
                      psmouse, set_properties) == 0) {
            if (!set_properties || alps_init(psmouse) == 0)
                return PSMOUSE_ALPS;
/*
 * Init failed, try basic relative protocols
 */
            max_proto = PSMOUSE_IMEX;
        }
    }

/*
 * Try OLPC HGPK touchpad.
 */
    if (max_proto > PSMOUSE_IMEX &&
        psmouse_do_detect(hgpk_detect, psmouse, set_properties) == 0) {
        if (!set_properties || hgpk_init(psmouse) == 0)
            return PSMOUSE_HGPK;
/*
 * Init failed, try basic relative protocols
 */
        max_proto = PSMOUSE_IMEX;
    }

/*
 * Try Elantech touchpad.
 */
    if (max_proto > PSMOUSE_IMEX &&
        psmouse_do_detect(elantech_detect, psmouse, set_properties) == 0) {
        if (!set_properties || elantech_init(psmouse) == 0)
            return PSMOUSE_ELANTECH;
/*
 * Init failed, try basic relative protocols
 */
        max_proto = PSMOUSE_IMEX;
    }

    if (max_proto > PSMOUSE_IMEX) {
        if (psmouse_do_detect(genius_detect,
                      psmouse, set_properties) == 0)
            return PSMOUSE_GENPS;

        if (psmouse_do_detect(ps2pp_init,
                      psmouse, set_properties) == 0)
            return PSMOUSE_PS2PP;

        if (psmouse_do_detect(trackpoint_detect,
                      psmouse, set_properties) == 0)
            return PSMOUSE_TRACKPOINT;

        if (psmouse_do_detect(touchkit_ps2_detect,
                      psmouse, set_properties) == 0)
            return PSMOUSE_TOUCHKIT_PS2;
    }

/*
 * Try Finger Sensing Pad. We do it here because its probe upsets
 * Trackpoint devices (causing TP_READ_ID command to time out).
 */
    if (max_proto > PSMOUSE_IMEX) {
        if (psmouse_do_detect(fsp_detect,
                      psmouse, set_properties) == 0) {
            if (!set_properties || fsp_init(psmouse) == 0)
                return PSMOUSE_FSP;
/*
 * Init failed, try basic relative protocols
 */
            max_proto = PSMOUSE_IMEX;
        }
    }

/*
 * Reset to defaults in case the device got confused by extended
 * protocol probes. Note that we follow up with full reset because
 * some mice put themselves to sleep when they see PSMOUSE_RESET_DIS.
 */
    ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_RESET_DIS);
    psmouse_reset(psmouse);

    if (max_proto >= PSMOUSE_IMEX &&
        psmouse_do_detect(im_explorer_detect,
                  psmouse, set_properties) == 0) {
        return PSMOUSE_IMEX;
    }

    if (max_proto >= PSMOUSE_IMPS &&
        psmouse_do_detect(intellimouse_detect,
                  psmouse, set_properties) == 0) {
        return PSMOUSE_IMPS;
    }

/*
 * Okay, all failed, we have a standard mouse here. The number of the buttons
 * is still a question, though. We assume 3.
 */
    psmouse_do_detect(ps2bare_detect, psmouse, set_properties);

    if (synaptics_hardware) {
/*
 * We detected Synaptics hardware but it did not respond to IMPS/2 probes.
 * We need to reset the touchpad because if there is a track point on the
 * pass through port it could get disabled while probing for protocol
 * extensions.
 */
        psmouse_reset(psmouse);
    }

    return PSMOUSE_PS2;
}

static const struct psmouse_protocol psmouse_protocols[] = {
    {
        .type       = PSMOUSE_PS2,
        .name       = "PS/2",
        .alias      = "bare",
        .maxproto   = true,
        .ignore_parity  = true,
        .detect     = ps2bare_detect,
    },
#ifdef CONFIG_MOUSE_PS2_LOGIPS2PP
    {
        .type       = PSMOUSE_PS2PP,
        .name       = "PS2++",
        .alias      = "logitech",
        .detect     = ps2pp_init,
    },
#endif
    {
        .type       = PSMOUSE_THINKPS,
        .name       = "ThinkPS/2",
        .alias      = "thinkps",
        .detect     = thinking_detect,
    },
    {
        .type       = PSMOUSE_GENPS,
        .name       = "GenPS/2",
        .alias      = "genius",
        .detect     = genius_detect,
    },
    {
        .type       = PSMOUSE_IMPS,
        .name       = "ImPS/2",
        .alias      = "imps",
        .maxproto   = true,
        .ignore_parity  = true,
        .detect     = intellimouse_detect,
    },
    {
        .type       = PSMOUSE_IMEX,
        .name       = "ImExPS/2",
        .alias      = "exps",
        .maxproto   = true,
        .ignore_parity  = true,
        .detect     = im_explorer_detect,
    },
#ifdef CONFIG_MOUSE_PS2_SYNAPTICS
    {
        .type       = PSMOUSE_SYNAPTICS,
        .name       = "SynPS/2",
        .alias      = "synaptics",
        .detect     = synaptics_detect,
        .init       = synaptics_init,
    },
    {
        .type       = PSMOUSE_SYNAPTICS_RELATIVE,
        .name       = "SynRelPS/2",
        .alias      = "synaptics-relative",
        .detect     = synaptics_detect,
        .init       = synaptics_init_relative,
    },
#endif
#ifdef CONFIG_MOUSE_PS2_ALPS
    {
        .type       = PSMOUSE_ALPS,
        .name       = "AlpsPS/2",
        .alias      = "alps",
        .detect     = alps_detect,
        .init       = alps_init,
    },
#endif
#ifdef CONFIG_MOUSE_PS2_LIFEBOOK
    {
        .type       = PSMOUSE_LIFEBOOK,
        .name       = "LBPS/2",
        .alias      = "lifebook",
        .init       = lifebook_init,
    },
#endif
#ifdef CONFIG_MOUSE_PS2_TRACKPOINT
    {
        .type       = PSMOUSE_TRACKPOINT,
        .name       = "TPPS/2",
        .alias      = "trackpoint",
        .detect     = trackpoint_detect,
    },
#endif
#ifdef CONFIG_MOUSE_PS2_TOUCHKIT
    {
        .type       = PSMOUSE_TOUCHKIT_PS2,
        .name       = "touchkitPS/2",
        .alias      = "touchkit",
        .detect     = touchkit_ps2_detect,
    },
#endif
#ifdef CONFIG_MOUSE_PS2_OLPC
    {
        .type       = PSMOUSE_HGPK,
        .name       = "OLPC HGPK",
        .alias      = "hgpk",
        .detect     = hgpk_detect,
    },
#endif
#ifdef CONFIG_MOUSE_PS2_ELANTECH
    {
        .type       = PSMOUSE_ELANTECH,
        .name       = "ETPS/2",
        .alias      = "elantech",
        .detect     = elantech_detect,
        .init       = elantech_init,
    },
#endif
#ifdef CONFIG_MOUSE_PS2_SENTELIC
    {
        .type       = PSMOUSE_FSP,
        .name       = "FSPPS/2",
        .alias      = "fsp",
        .detect     = fsp_detect,
        .init       = fsp_init,
    },
#endif
    {
        .type       = PSMOUSE_CORTRON,
        .name       = "CortronPS/2",
        .alias      = "cortps",
        .detect     = cortron_detect,
    },
    {
        .type       = PSMOUSE_AUTO,
        .name       = "auto",
        .alias      = "any",
        .maxproto   = true,
    },
};

static const struct psmouse_protocol *psmouse_protocol_by_type(enum psmouse_type type)
{
    int i;

    for (i = 0; i < ARRAY_SIZE(psmouse_protocols); i++)
        if (psmouse_protocols[i].type == type)
            return &psmouse_protocols[i];

    WARN_ON(1);
    return &psmouse_protocols[0];
}

static const struct psmouse_protocol *psmouse_protocol_by_name(const char *name, size_t len)
{
    const struct psmouse_protocol *p;
    int i;

    for (i = 0; i < ARRAY_SIZE(psmouse_protocols); i++) {
        p = &psmouse_protocols[i];

        if ((strlen(p->name) == len && !strncmp(p->name, name, len)) ||
            (strlen(p->alias) == len && !strncmp(p->alias, name, len)))
            return &psmouse_protocols[i];
    }

    return NULL;
}


/*
 * psmouse_probe() probes for a PS/2 mouse.
 */

static int psmouse_probe(struct psmouse *psmouse)
{
    struct ps2dev *ps2dev = &psmouse->ps2dev;
    unsigned char param[2];

/*
 * First, we check if it's a mouse. It should send 0x00 or 0x03
 * in case of an IntelliMouse in 4-byte mode or 0x04 for IM Explorer.
 * Sunrex K8561 IR Keyboard/Mouse reports 0xff on second and subsequent
 * ID queries, probably due to a firmware bug.
 */

    param[0] = 0xa5;
    if (ps2_command(ps2dev, param, PSMOUSE_CMD_GETID))
        return -1;

    if (param[0] != 0x00 && param[0] != 0x03 &&
        param[0] != 0x04 && param[0] != 0xff)
        return -1;

/*
 * Then we reset and disable the mouse so that it doesn't generate events.
 */

    if (ps2_command(ps2dev, NULL, PSMOUSE_CMD_RESET_DIS))
        psmouse_warn(psmouse, "Failed to reset mouse on %s\n",
                 ps2dev->serio->phys);

    return 0;
}

/*
 * psmouse_initialize() initializes the mouse to a sane state.
 */

static void psmouse_initialize(struct psmouse *psmouse)
{
/*
 * We set the mouse report rate, resolution and scaling.
 */

    if (psmouse_max_proto != PSMOUSE_PS2) {
        psmouse->set_rate(psmouse, psmouse->rate);
        psmouse->set_resolution(psmouse, psmouse->resolution);
        ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_SETSCALE11);
    }
}

/*
 * psmouse_activate() enables the mouse so that we get motion reports from it.
 */

int psmouse_activate(struct psmouse *psmouse)
{
    if (ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_ENABLE)) {
        psmouse_warn(psmouse, "Failed to enable mouse on %s\n",
                 psmouse->ps2dev.serio->phys);
        return -1;
    }

    psmouse_set_state(psmouse, PSMOUSE_ACTIVATED);
    return 0;
}

/*
 * psmouse_deactivate() puts the mouse into poll mode so that we don't get motion
 * reports from it unless we explicitly request it.
 */

int psmouse_deactivate(struct psmouse *psmouse)
{
    if (ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_DISABLE)) {
        psmouse_warn(psmouse, "Failed to deactivate mouse on %s\n",
                 psmouse->ps2dev.serio->phys);
        return -1;
    }

    psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);
    return 0;
}


/*
 * psmouse_resync() attempts to re-validate current protocol.
 */

static void psmouse_resync(struct work_struct *work)
{
    struct psmouse *parent = NULL, *psmouse =
        container_of(work, struct psmouse, resync_work.work);
    struct serio *serio = psmouse->ps2dev.serio;
    psmouse_ret_t rc = PSMOUSE_GOOD_DATA;
    bool failed = false, enabled = false;
    int i;

    mutex_lock(&psmouse_mutex);

    if (psmouse->state != PSMOUSE_RESYNCING)
        goto out;

    if (serio->parent && serio->id.type == SERIO_PS_PSTHRU) {
        parent = serio_get_drvdata(serio->parent);
        psmouse_deactivate(parent);
    }

/*
 * Some mice don't ACK commands sent while they are in the middle of
 * transmitting motion packet. To avoid delay we use ps2_sendbyte()
 * instead of ps2_command() which would wait for 200ms for an ACK
 * that may never come.
 * As an additional quirk ALPS touchpads may not only forget to ACK
 * disable command but will stop reporting taps, so if we see that
 * mouse at least once ACKs disable we will do full reconnect if ACK
 * is missing.
 */
    psmouse->num_resyncs++;

    if (ps2_sendbyte(&psmouse->ps2dev, PSMOUSE_CMD_DISABLE, 20)) {
        if (psmouse->num_resyncs < 3 || psmouse->acks_disable_command)
            failed = true;
    } else
        psmouse->acks_disable_command = true;

/*
 * Poll the mouse. If it was reset the packet will be shorter than
 * psmouse->pktsize and ps2_command will fail. We do not expect and
 * do not handle scenario when mouse "upgrades" its protocol while
 * disconnected since it would require additional delay. If we ever
 * see a mouse that does it we'll adjust the code.
 */
    if (!failed) {
        if (psmouse->poll(psmouse))
            failed = true;
        else {
            psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);
            for (i = 0; i < psmouse->pktsize; i++) {
                psmouse->pktcnt++;
                rc = psmouse->protocol_handler(psmouse);
                if (rc != PSMOUSE_GOOD_DATA)
                    break;
            }
            if (rc != PSMOUSE_FULL_PACKET)
                failed = true;
            psmouse_set_state(psmouse, PSMOUSE_RESYNCING);
        }
    }
/*
 * Now try to enable mouse. We try to do that even if poll failed and also
 * repeat our attempts 5 times, otherwise we may be left out with disabled
 * mouse.
 */
    for (i = 0; i < 5; i++) {
        if (!ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_ENABLE)) {
            enabled = true;
            break;
        }
        msleep(200);
    }

    if (!enabled) {
        psmouse_warn(psmouse, "failed to re-enable mouse on %s\n",
                 psmouse->ps2dev.serio->phys);
        failed = true;
    }

    if (failed) {
        psmouse_set_state(psmouse, PSMOUSE_IGNORE);
        psmouse_info(psmouse,
                 "resync failed, issuing reconnect request\n");
        serio_reconnect(serio);
    } else
        psmouse_set_state(psmouse, PSMOUSE_ACTIVATED);

    if (parent)
        psmouse_activate(parent);
 out:
    mutex_unlock(&psmouse_mutex);
}

/*
 * psmouse_cleanup() resets the mouse into power-on state.
 */

static void psmouse_cleanup(struct serio *serio)
{
    struct psmouse *psmouse = serio_get_drvdata(serio);
    struct psmouse *parent = NULL;

    mutex_lock(&psmouse_mutex);

    if (serio->parent && serio->id.type == SERIO_PS_PSTHRU) {
        parent = serio_get_drvdata(serio->parent);
        psmouse_deactivate(parent);
    }

    psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);

    /*
     * Disable stream mode so cleanup routine can proceed undisturbed.
     */
    if (ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_DISABLE))
        psmouse_warn(psmouse, "Failed to disable mouse on %s\n",
                 psmouse->ps2dev.serio->phys);

    if (psmouse->cleanup)
        psmouse->cleanup(psmouse);

/*
 * Reset the mouse to defaults (bare PS/2 protocol).
 */
    ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_RESET_DIS);

/*
 * Some boxes, such as HP nx7400, get terribly confused if mouse
 * is not fully enabled before suspending/shutting down.
 */
    ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_ENABLE);

    if (parent) {
        if (parent->pt_deactivate)
            parent->pt_deactivate(parent);

        psmouse_activate(parent);
    }

    mutex_unlock(&psmouse_mutex);
}

/*
 * psmouse_disconnect() closes and frees.
 */

static void psmouse_disconnect(struct serio *serio)
{
    struct psmouse *psmouse, *parent = NULL;

    psmouse = serio_get_drvdata(serio);

    sysfs_remove_group(&serio->dev.kobj, &psmouse_attribute_group);

    mutex_lock(&psmouse_mutex);

    psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);

    /* make sure we don't have a resync in progress */
    mutex_unlock(&psmouse_mutex);
    flush_workqueue(kpsmoused_wq);
    mutex_lock(&psmouse_mutex);

    if (serio->parent && serio->id.type == SERIO_PS_PSTHRU) {
        parent = serio_get_drvdata(serio->parent);
        psmouse_deactivate(parent);
    }

    if (psmouse->disconnect)
        psmouse->disconnect(psmouse);

    if (parent && parent->pt_deactivate)
        parent->pt_deactivate(parent);

    psmouse_set_state(psmouse, PSMOUSE_IGNORE);

    serio_close(serio);
    serio_set_drvdata(serio, NULL);
    input_unregister_device(psmouse->dev);
    kfree(psmouse);

    if (parent)
        psmouse_activate(parent);

    mutex_unlock(&psmouse_mutex);
}

static int psmouse_switch_protocol(struct psmouse *psmouse,
                   const struct psmouse_protocol *proto)
{
    const struct psmouse_protocol *selected_proto;
    struct input_dev *input_dev = psmouse->dev;

    input_dev->dev.parent = &psmouse->ps2dev.serio->dev;

    if (proto && (proto->detect || proto->init)) {
        psmouse_apply_defaults(psmouse);

        if (proto->detect && proto->detect(psmouse, true) < 0)
            return -1;

        if (proto->init && proto->init(psmouse) < 0)
            return -1;

        psmouse->type = proto->type;
        selected_proto = proto;
    } else {
        psmouse->type = psmouse_extensions(psmouse,
                           psmouse_max_proto, true);
        selected_proto = psmouse_protocol_by_type(psmouse->type);
    }

    psmouse->ignore_parity = selected_proto->ignore_parity;

    /*
     * If mouse's packet size is 3 there is no point in polling the
     * device in hopes to detect protocol reset - we won't get less
     * than 3 bytes response anyhow.
     */
    if (psmouse->pktsize == 3)
        psmouse->resync_time = 0;

    /*
     * Some smart KVMs fake response to POLL command returning just
     * 3 bytes and messing up our resync logic, so if initial poll
     * fails we won't try polling the device anymore. Hopefully
     * such KVM will maintain initially selected protocol.
     */
    if (psmouse->resync_time && psmouse->poll(psmouse))
        psmouse->resync_time = 0;

    snprintf(psmouse->devname, sizeof(psmouse->devname), "%s %s %s",
         selected_proto->name, psmouse->vendor, psmouse->name);

    input_dev->name = psmouse->devname;
    input_dev->phys = psmouse->phys;
    input_dev->id.bustype = BUS_I8042;
    input_dev->id.vendor = 0x0002;
    input_dev->id.product = psmouse->type;
    input_dev->id.version = psmouse->model;

    return 0;
}

/*
 * psmouse_connect() is a callback from the serio module when
 * an unhandled serio port is found.
 */
static int psmouse_connect(struct serio *serio, struct serio_driver *drv)
{
    struct psmouse *psmouse, *parent = NULL;
    struct input_dev *input_dev;
    int retval = 0, error = -ENOMEM;

    mutex_lock(&psmouse_mutex);

    /*
     * If this is a pass-through port deactivate parent so the device
     * connected to this port can be successfully identified
     */
    if (serio->parent && serio->id.type == SERIO_PS_PSTHRU) {
        parent = serio_get_drvdata(serio->parent);
        psmouse_deactivate(parent);
    }

    psmouse = kzalloc(sizeof(struct psmouse), GFP_KERNEL);
    input_dev = input_allocate_device();
    if (!psmouse || !input_dev)
        goto err_free;

    ps2_init(&psmouse->ps2dev, serio);
    INIT_DELAYED_WORK(&psmouse->resync_work, psmouse_resync);
    psmouse->dev = input_dev;
    snprintf(psmouse->phys, sizeof(psmouse->phys), "%s/input0", serio->phys);

    psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);

    serio_set_drvdata(serio, psmouse);

    error = serio_open(serio, drv);
    if (error)
        goto err_clear_drvdata;

    if (psmouse_probe(psmouse) < 0) {
        error = -ENODEV;
        goto err_close_serio;
    }

    psmouse->rate = psmouse_rate;
    psmouse->resolution = psmouse_resolution;
    psmouse->resetafter = psmouse_resetafter;
    psmouse->resync_time = parent ? 0 : psmouse_resync_time;
    psmouse->smartscroll = psmouse_smartscroll;

    psmouse_switch_protocol(psmouse, NULL);

    psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);
    psmouse_initialize(psmouse);

    error = input_register_device(psmouse->dev);
    if (error)
        goto err_protocol_disconnect;

    if (parent && parent->pt_activate)
        parent->pt_activate(parent);

    error = sysfs_create_group(&serio->dev.kobj, &psmouse_attribute_group);
    if (error)
        goto err_pt_deactivate;

    psmouse_activate(psmouse);

 out:
    /* If this is a pass-through port the parent needs to be re-activated */
    if (parent)
        psmouse_activate(parent);

    mutex_unlock(&psmouse_mutex);
    return retval;

 err_pt_deactivate:
    if (parent && parent->pt_deactivate)
        parent->pt_deactivate(parent);
    input_unregister_device(psmouse->dev);
    input_dev = NULL; /* so we don't try to free it below */
 err_protocol_disconnect:
    if (psmouse->disconnect)
        psmouse->disconnect(psmouse);
    psmouse_set_state(psmouse, PSMOUSE_IGNORE);
 err_close_serio:
    serio_close(serio);
 err_clear_drvdata:
    serio_set_drvdata(serio, NULL);
 err_free:
    input_free_device(input_dev);
    kfree(psmouse);

    retval = error;
    goto out;
}


static int psmouse_reconnect(struct serio *serio)
{
    struct psmouse *psmouse = serio_get_drvdata(serio);
    struct psmouse *parent = NULL;
    struct serio_driver *drv = serio->drv;
    unsigned char type;
    int rc = -1;

    if (!drv || !psmouse) {
        psmouse_dbg(psmouse,
                "reconnect request, but serio is disconnected, ignoring...\n");
        return -1;
    }

    mutex_lock(&psmouse_mutex);

    if (serio->parent && serio->id.type == SERIO_PS_PSTHRU) {
        parent = serio_get_drvdata(serio->parent);
        psmouse_deactivate(parent);
    }

    psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);

    if (psmouse->reconnect) {
        if (psmouse->reconnect(psmouse))
            goto out;
    } else {
        psmouse_reset(psmouse);

        if (psmouse_probe(psmouse) < 0)
            goto out;

        type = psmouse_extensions(psmouse, psmouse_max_proto, false);
        if (psmouse->type != type)
            goto out;
    }

    /*
     * OK, the device type (and capabilities) match the old one,
     * we can continue using it, complete initialization
     */
    psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);

    psmouse_initialize(psmouse);

    if (parent && parent->pt_activate)
        parent->pt_activate(parent);

    psmouse_activate(psmouse);
    rc = 0;

out:
    /* If this is a pass-through port the parent waits to be activated */
    if (parent)
        psmouse_activate(parent);

    mutex_unlock(&psmouse_mutex);
    return rc;
}

static struct serio_device_id psmouse_serio_ids[] = {
    {
        .type   = SERIO_8042,
        .proto  = SERIO_ANY,
        .id = SERIO_ANY,
        .extra  = SERIO_ANY,
    },
    {
        .type   = SERIO_PS_PSTHRU,
        .proto  = SERIO_ANY,
        .id = SERIO_ANY,
        .extra  = SERIO_ANY,
    },
    { 0 }
};

MODULE_DEVICE_TABLE(serio, psmouse_serio_ids);

static struct serio_driver psmouse_drv = {
    .driver     = {
        .name   = "psmouse",
    },
    .description    = DRIVER_DESC,
    .id_table   = psmouse_serio_ids,
    .interrupt  = psmouse_interrupt,
    .connect    = psmouse_connect,
    .reconnect  = psmouse_reconnect,
    .disconnect = psmouse_disconnect,
    .cleanup    = psmouse_cleanup,
};

ssize_t psmouse_attr_show_helper(struct device *dev, struct device_attribute *devattr,
                 char *buf)
{
    struct serio *serio = to_serio_port(dev);
    struct psmouse_attribute *attr = to_psmouse_attr(devattr);
    struct psmouse *psmouse;

    psmouse = serio_get_drvdata(serio);

    return attr->show(psmouse, attr->data, buf);
}

ssize_t psmouse_attr_set_helper(struct device *dev, struct device_attribute *devattr,
                const char *buf, size_t count)
{
    struct serio *serio = to_serio_port(dev);
    struct psmouse_attribute *attr = to_psmouse_attr(devattr);
    struct psmouse *psmouse, *parent = NULL;
    int retval;

    retval = mutex_lock_interruptible(&psmouse_mutex);
    if (retval)
        goto out;

    psmouse = serio_get_drvdata(serio);

    if (attr->protect) {
        if (psmouse->state == PSMOUSE_IGNORE) {
            retval = -ENODEV;
            goto out_unlock;
        }

        if (serio->parent && serio->id.type == SERIO_PS_PSTHRU) {
            parent = serio_get_drvdata(serio->parent);
            psmouse_deactivate(parent);
        }

        psmouse_deactivate(psmouse);
    }

    retval = attr->set(psmouse, attr->data, buf, count);

    if (attr->protect) {
        if (retval != -ENODEV)
            psmouse_activate(psmouse);

        if (parent)
            psmouse_activate(parent);
    }

 out_unlock:
    mutex_unlock(&psmouse_mutex);
 out:
    return retval;
}

static ssize_t psmouse_show_int_attr(struct psmouse *psmouse, void *offset, char *buf)
{
    unsigned int *field = (unsigned int *)((char *)psmouse + (size_t)offset);

    return sprintf(buf, "%u\n", *field);
}

static ssize_t psmouse_set_int_attr(struct psmouse *psmouse, void *offset, const char *buf, size_t count)
{
    unsigned int *field = (unsigned int *)((char *)psmouse + (size_t)offset);
    unsigned int value;
    int err;

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

    *field = value;

    return count;
}

static ssize_t psmouse_attr_show_protocol(struct psmouse *psmouse, void *data, char *buf)
{
    return sprintf(buf, "%s\n", psmouse_protocol_by_type(psmouse->type)->name);
}

static ssize_t psmouse_attr_set_protocol(struct psmouse *psmouse, void *data, const char *buf, size_t count)
{
    struct serio *serio = psmouse->ps2dev.serio;
    struct psmouse *parent = NULL;
    struct input_dev *old_dev, *new_dev;
    const struct psmouse_protocol *proto, *old_proto;
    int error;
    int retry = 0;

    proto = psmouse_protocol_by_name(buf, count);
    if (!proto)
        return -EINVAL;

    if (psmouse->type == proto->type)
        return count;

    new_dev = input_allocate_device();
    if (!new_dev)
        return -ENOMEM;

    while (!list_empty(&serio->children)) {
        if (++retry > 3) {
            psmouse_warn(psmouse,
                     "failed to destroy children ports, protocol change aborted.\n");
            input_free_device(new_dev);
            return -EIO;
        }

        mutex_unlock(&psmouse_mutex);
        serio_unregister_child_port(serio);
        mutex_lock(&psmouse_mutex);

        if (serio->drv != &psmouse_drv) {
            input_free_device(new_dev);
            return -ENODEV;
        }

        if (psmouse->type == proto->type) {
            input_free_device(new_dev);
            return count; /* switched by other thread */
        }
    }

    if (serio->parent && serio->id.type == SERIO_PS_PSTHRU) {
        parent = serio_get_drvdata(serio->parent);
        if (parent->pt_deactivate)
            parent->pt_deactivate(parent);
    }

    old_dev = psmouse->dev;
    old_proto = psmouse_protocol_by_type(psmouse->type);

    if (psmouse->disconnect)
        psmouse->disconnect(psmouse);

    psmouse_set_state(psmouse, PSMOUSE_IGNORE);

    psmouse->dev = new_dev;
    psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);

    if (psmouse_switch_protocol(psmouse, proto) < 0) {
        psmouse_reset(psmouse);
        /* default to PSMOUSE_PS2 */
        psmouse_switch_protocol(psmouse, &psmouse_protocols[0]);
    }

    psmouse_initialize(psmouse);
    psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);

    error = input_register_device(psmouse->dev);
    if (error) {
        if (psmouse->disconnect)
            psmouse->disconnect(psmouse);

        psmouse_set_state(psmouse, PSMOUSE_IGNORE);
        input_free_device(new_dev);
        psmouse->dev = old_dev;
        psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);
        psmouse_switch_protocol(psmouse, old_proto);
        psmouse_initialize(psmouse);
        psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);

        return error;
    }

    input_unregister_device(old_dev);

    if (parent && parent->pt_activate)
        parent->pt_activate(parent);

    return count;
}

static ssize_t psmouse_attr_set_rate(struct psmouse *psmouse, void *data, const char *buf, size_t count)
{
    unsigned int value;
    int err;

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

    psmouse->set_rate(psmouse, value);
    return count;
}

static ssize_t psmouse_attr_set_resolution(struct psmouse *psmouse, void *data, const char *buf, size_t count)
{
    unsigned int value;
    int err;

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

    psmouse->set_resolution(psmouse, value);
    return count;
}


static int psmouse_set_maxproto(const char *val, const struct kernel_param *kp)
{
    const struct psmouse_protocol *proto;

    if (!val)
        return -EINVAL;

    proto = psmouse_protocol_by_name(val, strlen(val));

    if (!proto || !proto->maxproto)
        return -EINVAL;

    *((unsigned int *)kp->arg) = proto->type;

    return 0;
}

static int psmouse_get_maxproto(char *buffer, const struct kernel_param *kp)
{
    int type = *((unsigned int *)kp->arg);

    return sprintf(buffer, "%s", psmouse_protocol_by_type(type)->name);
}

static int __init psmouse_init(void)
{
    int err;

    lifebook_module_init();
    synaptics_module_init();
    hgpk_module_init();

    kpsmoused_wq = create_singlethread_workqueue("kpsmoused");
    if (!kpsmoused_wq) {
        pr_err("failed to create kpsmoused workqueue\n");
        return -ENOMEM;
    }

    err = serio_register_driver(&psmouse_drv);
    if (err)
        destroy_workqueue(kpsmoused_wq);

    return err;
}

static void __exit psmouse_exit(void)
{
    serio_unregister_driver(&psmouse_drv);
    destroy_workqueue(kpsmoused_wq);
}

module_init(psmouse_init);
module_exit(psmouse_exit);