/*      $NetBSD: hid.c,v 1.17 2001/11/13 06:24:53 lukem Exp $   */
/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 1998 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Lennart Augustsson (lennart@augustsson.net) at
 * Carlstedt Research & Technology.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "opt_hid.h"

#include <sys/param.h>
#include <sys/bus.h>
#include <sys/kdb.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/sysctl.h>

#define HID_DEBUG_VAR   hid_debug
#include <dev/hid/hid.h>
#include <dev/hid/hidquirk.h>

#include "hid_if.h"

/*
 * Define this unconditionally in case a kernel module is loaded that
 * has been compiled with debugging options.
 */
int     hid_debug = 0;

SYSCTL_NODE(_hw, OID_AUTO, hid, CTLFLAG_RW, 0, "HID debugging");
SYSCTL_INT(_hw_hid, OID_AUTO, debug, CTLFLAG_RWTUN,
    &hid_debug, 0, "Debug level");

static void hid_clear_local(struct hid_item *);
static uint8_t hid_get_byte(struct hid_data *s, const uint16_t wSize);

static hid_test_quirk_t hid_test_quirk_w;
hid_test_quirk_t *hid_test_quirk_p = &hid_test_quirk_w;

#define MAXUSAGE 64
#define MAXPUSH 4
#define MAXID 16
#define MAXLOCCNT 2048

struct hid_pos_data {
        uint32_t rid;
        uint32_t pos;
};

struct hid_data {
        const uint8_t *start;
        const uint8_t *end;
        const uint8_t *p;
        struct hid_item cur[MAXPUSH];
        struct hid_pos_data last_pos[MAXID];
        uint32_t usages_min[MAXUSAGE];
        uint32_t usages_max[MAXUSAGE];
        uint32_t usage_last;    /* last seen usage */
        uint32_t loc_size;      /* last seen size */
        uint32_t loc_count;     /* last seen count */
        uint32_t ncount;        /* end usage item count */
        uint32_t icount;        /* current usage item count */
        uint8_t kindset;        /* we have 5 kinds so 8 bits are enough */
        uint8_t pushlevel;      /* current pushlevel */
        uint8_t nusage;         /* end "usages_min/max" index */
        uint8_t iusage;         /* current "usages_min/max" index */
        uint8_t ousage;         /* current "usages_min/max" offset */
        uint8_t susage;         /* usage set flags */
};

/*------------------------------------------------------------------------*
 *      hid_clear_local
 *------------------------------------------------------------------------*/
static void
hid_clear_local(struct hid_item *c)
{

        c->loc.count = 0;
        c->loc.size = 0;
        c->nusages = 0;
        memset(c->usages, 0, sizeof(c->usages));
        c->usage_minimum = 0;
        c->usage_maximum = 0;
        c->designator_index = 0;
        c->designator_minimum = 0;
        c->designator_maximum = 0;
        c->string_index = 0;
        c->string_minimum = 0;
        c->string_maximum = 0;
        c->set_delimiter = 0;
}

static void
hid_switch_rid(struct hid_data *s, struct hid_item *c, uint32_t next_rID)
{
        uint8_t i;

        /* check for same report ID - optimise */

        if (c->report_ID == next_rID)
                return;

        /* save current position for current rID */

        if (c->report_ID == 0) {
                i = 0;
        } else {
                for (i = 1; i != MAXID; i++) {
                        if (s->last_pos[i].rid == c->report_ID)
                                break;
                        if (s->last_pos[i].rid == 0)
                                break;
                }
        }
        if (i != MAXID) {
                s->last_pos[i].rid = c->report_ID;
                s->last_pos[i].pos = c->loc.pos;
        }

        /* store next report ID */

        c->report_ID = next_rID;

        /* lookup last position for next rID */

        if (next_rID == 0) {
                i = 0;
        } else {
                for (i = 1; i != MAXID; i++) {
                        if (s->last_pos[i].rid == next_rID)
                                break;
                        if (s->last_pos[i].rid == 0)
                                break;
                }
        }
        if (i != MAXID) {
                s->last_pos[i].rid = next_rID;
                c->loc.pos = s->last_pos[i].pos;
        } else {
                DPRINTF("Out of RID entries, position is set to zero!\n");
                c->loc.pos = 0;
        }
}

/*------------------------------------------------------------------------*
 *      hid_start_parse
 *------------------------------------------------------------------------*/
struct hid_data *
hid_start_parse(const void *d, hid_size_t len, int kindset)
{
        struct hid_data *s;

        if ((kindset-1) & kindset) {
                DPRINTFN(0, "Only one bit can be "
                    "set in the kindset\n");
                return (NULL);
        }

        s = malloc(sizeof *s, M_TEMP, M_WAITOK | M_ZERO);
        s->start = s->p = d;
        s->end = ((const uint8_t *)d) + len;
        s->kindset = kindset;
        return (s);
}

/*------------------------------------------------------------------------*
 *      hid_end_parse
 *------------------------------------------------------------------------*/
void
hid_end_parse(struct hid_data *s)
{
        if (s == NULL)
                return;

        free(s, M_TEMP);
}

/*------------------------------------------------------------------------*
 *      get byte from HID descriptor
 *------------------------------------------------------------------------*/
static uint8_t
hid_get_byte(struct hid_data *s, const uint16_t wSize)
{
        const uint8_t *ptr;
        uint8_t retval;

        ptr = s->p;

        /* check if end is reached */
        if (ptr == s->end)
                return (0);

        /* read out a byte */
        retval = *ptr;

        /* check if data pointer can be advanced by "wSize" bytes */
        if ((s->end - ptr) < wSize)
                ptr = s->end;
        else
                ptr += wSize;

        /* update pointer */
        s->p = ptr;

        return (retval);
}

/*------------------------------------------------------------------------*
 *      hid_get_item
 *------------------------------------------------------------------------*/
int
hid_get_item(struct hid_data *s, struct hid_item *h)
{
        struct hid_item *c;
        unsigned int bTag, bType, bSize;
        uint32_t oldpos;
        int32_t mask;
        int32_t dval;
        uint32_t uval;

        if (s == NULL)
                return (0);

        c = &s->cur[s->pushlevel];

 top:
        /* check if there is an array of items */
        if (s->icount < s->ncount) {
                /* get current usage */
                if (s->iusage < s->nusage) {
                        uval = s->usages_min[s->iusage] + s->ousage;
                        c->usage = uval;
                        s->usage_last = uval;
                        if (uval == s->usages_max[s->iusage]) {
                                s->iusage ++;
                                s->ousage = 0;
                        } else {
                                s->ousage ++;
                        }
                } else {
                        DPRINTFN(1, "Using last usage\n");
                        uval = s->usage_last;
                }
                c->nusages = 1;
                /* array type HID item may have multiple usages */
                while ((c->flags & HIO_VARIABLE) == 0 && s->ousage == 0 &&
                    s->iusage < s->nusage && c->nusages < HID_ITEM_MAXUSAGE)
                        c->usages[c->nusages++] = s->usages_min[s->iusage++];
                if ((c->flags & HIO_VARIABLE) == 0 && s->ousage == 0 &&
                    s->iusage < s->nusage)
                        DPRINTFN(0, "HID_ITEM_MAXUSAGE should be increased "
                            "up to %hhu to parse the HID report descriptor\n",
                            s->nusage);
                s->icount ++;
                /* 
                 * Only copy HID item, increment position and return
                 * if correct kindset!
                 */
                if (s->kindset & (1 << c->kind)) {
                        *h = *c;
                        DPRINTFN(1, "%u,%u,%u\n", h->loc.pos,
                            h->loc.size, h->loc.count);
                        c->loc.pos += c->loc.size * c->loc.count;
                        return (1);
                }
        }

        /* reset state variables */
        s->icount = 0;
        s->ncount = 0;
        s->iusage = 0;
        s->nusage = 0;
        s->susage = 0;
        s->ousage = 0;
        hid_clear_local(c);

        /* get next item */
        while (s->p != s->end) {
                bSize = hid_get_byte(s, 1);
                if (bSize == 0xfe) {
                        /* long item */
                        bSize = hid_get_byte(s, 1);
                        bSize |= hid_get_byte(s, 1) << 8;
                        bTag = hid_get_byte(s, 1);
                        bType = 0xff;   /* XXX what should it be */
                } else {
                        /* short item */
                        bTag = bSize >> 4;
                        bType = (bSize >> 2) & 3;
                        bSize &= 3;
                        if (bSize == 3)
                                bSize = 4;
                }
                switch (bSize) {
                case 0:
                        uval = 0;
                        dval = uval;
                        mask = 0;
                        break;
                case 1:
                        uval = hid_get_byte(s, 1);
                        dval = (int8_t)uval;
                        mask = 0xFF;
                        break;
                case 2:
                        uval = hid_get_byte(s, 1);
                        uval |= hid_get_byte(s, 1) << 8;
                        dval = (int16_t)uval;
                        mask = 0xFFFF;
                        break;
                case 4:
                        uval = hid_get_byte(s, 1);
                        uval |= hid_get_byte(s, 1) << 8;
                        uval |= hid_get_byte(s, 1) << 16;
                        uval |= hid_get_byte(s, 1) << 24;
                        dval = uval;
                        mask = 0xFFFFFFFF;
                        break;
                default:
                        uval = hid_get_byte(s, bSize);
                        dval = uval;
                        DPRINTFN(0, "bad length %u (data=0x%02x)\n",
                            bSize, dval);
                        continue;
                }

                switch (bType) {
                case 0:         /* Main */
                        switch (bTag) {
                        case 8: /* Input */
                                c->kind = hid_input;
                ret:
                                c->flags = uval;
                                c->loc.count = s->loc_count;
                                c->loc.size = s->loc_size;

                                if (c->flags & HIO_VARIABLE) {
                                        /* range check usage count */
                                        if (c->loc.count > MAXLOCCNT) {
                                                DPRINTFN(0, "Number of "
                                                    "items(%u) truncated to %u\n",
                                                    (unsigned)(c->loc.count),
                                                    MAXLOCCNT);
                                                s->ncount = MAXLOCCNT;
                                        } else
                                                s->ncount = c->loc.count;

                                        /* 
                                         * The "top" loop will return
                                         * one and one item:
                                         */
                                        c->loc.count = 1;
                                } else {
                                        s->ncount = 1;
                                }
                                goto top;

                        case 9: /* Output */
                                c->kind = hid_output;
                                goto ret;
                        case 10:        /* Collection */
                                c->kind = hid_collection;
                                c->collection = uval;
                                c->collevel++;
                                c->usage = s->usage_last;
                                c->nusages = 1;
                                *h = *c;
                                return (1);
                        case 11:        /* Feature */
                                c->kind = hid_feature;
                                goto ret;
                        case 12:        /* End collection */
                                c->kind = hid_endcollection;
                                if (c->collevel == 0) {
                                        DPRINTFN(0, "invalid end collection\n");
                                        return (0);
                                }
                                c->collevel--;
                                *h = *c;
                                return (1);
                        default:
                                DPRINTFN(0, "Main bTag=%d\n", bTag);
                                break;
                        }
                        break;
                case 1:         /* Global */
                        switch (bTag) {
                        case 0:
                                c->_usage_page = uval << 16;
                                break;
                        case 1:
                                c->logical_minimum = dval;
                                break;
                        case 2:
                                c->logical_maximum = dval;
                                break;
                        case 3:
                                c->physical_minimum = dval;
                                break;
                        case 4:
                                c->physical_maximum = dval;
                                break;
                        case 5:
                                c->unit_exponent = uval;
                                break;
                        case 6:
                                c->unit = uval;
                                break;
                        case 7:
                                /* mask because value is unsigned */
                                s->loc_size = uval & mask;
                                break;
                        case 8:
                                hid_switch_rid(s, c, uval & mask);
                                break;
                        case 9:
                                /* mask because value is unsigned */
                                s->loc_count = uval & mask;
                                break;
                        case 10:        /* Push */
                                /* stop parsing, if invalid push level */
                                if ((s->pushlevel + 1) >= MAXPUSH) {
                                        DPRINTFN(0, "Cannot push item @ %d\n", s->pushlevel);
                                        return (0);
                                }
                                s->pushlevel ++;
                                s->cur[s->pushlevel] = *c;
                                /* store size and count */
                                c->loc.size = s->loc_size;
                                c->loc.count = s->loc_count;
                                /* update current item pointer */
                                c = &s->cur[s->pushlevel];
                                break;
                        case 11:        /* Pop */
                                /* stop parsing, if invalid push level */
                                if (s->pushlevel == 0) {
                                        DPRINTFN(0, "Cannot pop item @ 0\n");
                                        return (0);
                                }
                                s->pushlevel --;
                                /* preserve position */
                                oldpos = c->loc.pos;
                                c = &s->cur[s->pushlevel];
                                /* restore size and count */
                                s->loc_size = c->loc.size;
                                s->loc_count = c->loc.count;
                                /* set default item location */
                                c->loc.pos = oldpos;
                                c->loc.size = 0;
                                c->loc.count = 0;
                                break;
                        default:
                                DPRINTFN(0, "Global bTag=%d\n", bTag);
                                break;
                        }
                        break;
                case 2:         /* Local */
                        switch (bTag) {
                        case 0:
                                if (bSize != 4)
                                        uval = (uval & mask) | c->_usage_page;

                                /* set last usage, in case of a collection */
                                s->usage_last = uval;

                                if (s->nusage < MAXUSAGE) {
                                        s->usages_min[s->nusage] = uval;
                                        s->usages_max[s->nusage] = uval;
                                        s->nusage ++;
                                } else {
                                        DPRINTFN(0, "max usage reached\n");
                                }

                                /* clear any pending usage sets */
                                s->susage = 0;
                                break;
                        case 1:
                                s->susage |= 1;

                                if (bSize != 4)
                                        uval = (uval & mask) | c->_usage_page;
                                c->usage_minimum = uval;

                                goto check_set;
                        case 2:
                                s->susage |= 2;

                                if (bSize != 4)
                                        uval = (uval & mask) | c->_usage_page;
                                c->usage_maximum = uval;

                        check_set:
                                if (s->susage != 3)
                                        break;

                                /* sanity check */
                                if ((s->nusage < MAXUSAGE) &&
                                    (c->usage_minimum <= c->usage_maximum)) {
                                        /* add usage range */
                                        s->usages_min[s->nusage] = 
                                            c->usage_minimum;
                                        s->usages_max[s->nusage] = 
                                            c->usage_maximum;
                                        s->nusage ++;
                                } else {
                                        DPRINTFN(0, "Usage set dropped\n");
                                }
                                s->susage = 0;
                                break;
                        case 3:
                                c->designator_index = uval;
                                break;
                        case 4:
                                c->designator_minimum = uval;
                                break;
                        case 5:
                                c->designator_maximum = uval;
                                break;
                        case 7:
                                c->string_index = uval;
                                break;
                        case 8:
                                c->string_minimum = uval;
                                break;
                        case 9:
                                c->string_maximum = uval;
                                break;
                        case 10:
                                c->set_delimiter = uval;
                                break;
                        default:
                                DPRINTFN(0, "Local bTag=%d\n", bTag);
                                break;
                        }
                        break;
                default:
                        DPRINTFN(0, "default bType=%d\n", bType);
                        break;
                }
        }
        return (0);
}

/*------------------------------------------------------------------------*
 *      hid_report_size
 *------------------------------------------------------------------------*/
int
hid_report_size(const void *buf, hid_size_t len, enum hid_kind k, uint8_t id)
{
        struct hid_data *d;
        struct hid_item h;
        uint32_t temp;
        uint32_t hpos;
        uint32_t lpos;
        int report_id = 0;

        hpos = 0;
        lpos = 0xFFFFFFFF;

        for (d = hid_start_parse(buf, len, 1 << k); hid_get_item(d, &h);) {
                if (h.kind == k && h.report_ID == id) {
                        /* compute minimum */
                        if (lpos > h.loc.pos)
                                lpos = h.loc.pos;
                        /* compute end position */
                        temp = h.loc.pos + (h.loc.size * h.loc.count);
                        /* compute maximum */
                        if (hpos < temp)
                                hpos = temp;
                        if (h.report_ID != 0)
                                report_id = 1;
                }
        }
        hid_end_parse(d);

        /* safety check - can happen in case of currupt descriptors */
        if (lpos > hpos)
                temp = 0;
        else
                temp = hpos - lpos;

        /* return length in bytes rounded up */
        return ((temp + 7) / 8 + report_id);
}

int
hid_report_size_max(const void *buf, hid_size_t len, enum hid_kind k,
    uint8_t *id)
{
        struct hid_data *d;
        struct hid_item h;
        uint32_t temp;
        uint32_t hpos;
        uint32_t lpos;
        uint8_t any_id;

        any_id = 0;
        hpos = 0;
        lpos = 0xFFFFFFFF;

        for (d = hid_start_parse(buf, len, 1 << k); hid_get_item(d, &h);) {
                if (h.kind == k) {
                        /* check for ID-byte presence */
                        if ((h.report_ID != 0) && !any_id) {
                                if (id != NULL)
                                        *id = h.report_ID;
                                any_id = 1;
                        }
                        /* compute minimum */
                        if (lpos > h.loc.pos)
                                lpos = h.loc.pos;
                        /* compute end position */
                        temp = h.loc.pos + (h.loc.size * h.loc.count);
                        /* compute maximum */
                        if (hpos < temp)
                                hpos = temp;
                }
        }
        hid_end_parse(d);

        /* safety check - can happen in case of currupt descriptors */
        if (lpos > hpos)
                temp = 0;
        else
                temp = hpos - lpos;

        /* check for ID byte */
        if (any_id)
                temp += 8;
        else if (id != NULL)
                *id = 0;

        /* return length in bytes rounded up */
        return ((temp + 7) / 8);
}

/*------------------------------------------------------------------------*
 *      hid_locate
 *------------------------------------------------------------------------*/
int
hid_locate(const void *desc, hid_size_t size, int32_t u, enum hid_kind k,
    uint8_t index, struct hid_location *loc, uint32_t *flags, uint8_t *id)
{
        struct hid_data *d;
        struct hid_item h;
        int i;

        for (d = hid_start_parse(desc, size, 1 << k); hid_get_item(d, &h);) {
                for (i = 0; i < h.nusages; i++) {
                        if (h.kind == k && h.usages[i] == u) {
                                if (index--)
                                        break;
                                if (loc != NULL)
                                        *loc = h.loc;
                                if (flags != NULL)
                                        *flags = h.flags;
                                if (id != NULL)
                                        *id = h.report_ID;
                                hid_end_parse(d);
                                return (1);
                        }
                }
        }
        if (loc != NULL)
                loc->size = 0;
        if (flags != NULL)
                *flags = 0;
        if (id != NULL)
                *id = 0;
        hid_end_parse(d);
        return (0);
}

/*------------------------------------------------------------------------*
 *      hid_get_data
 *------------------------------------------------------------------------*/
static uint32_t
hid_get_data_sub(const uint8_t *buf, hid_size_t len, struct hid_location *loc,
    int is_signed)
{
        uint32_t hpos = loc->pos;
        uint32_t hsize = loc->size;
        uint32_t data;
        uint32_t rpos;
        uint8_t n;

        DPRINTFN(11, "hid_get_data: loc %d/%d\n", hpos, hsize);

        /* Range check and limit */
        if (hsize == 0)
                return (0);
        if (hsize > 32)
                hsize = 32;

        /* Get data in a safe way */    
        data = 0;
        rpos = (hpos / 8);
        n = (hsize + 7) / 8;
        rpos += n;
        while (n--) {
                rpos--;
                if (rpos < len)
                        data |= buf[rpos] << (8 * n);
        }

        /* Correctly shift down data */
        data = (data >> (hpos % 8));
        n = 32 - hsize;

        /* Mask and sign extend in one */
        if (is_signed != 0)
                data = (int32_t)((int32_t)data << n) >> n;
        else
                data = (uint32_t)((uint32_t)data << n) >> n;

        DPRINTFN(11, "hid_get_data: loc %d/%d = %lu\n",
            loc->pos, loc->size, (long)data);
        return (data);
}

int32_t
hid_get_data(const uint8_t *buf, hid_size_t len, struct hid_location *loc)
{
        return (hid_get_data_sub(buf, len, loc, 1));
}

uint32_t
hid_get_udata(const uint8_t *buf, hid_size_t len, struct hid_location *loc)
{
        return (hid_get_data_sub(buf, len, loc, 0));
}

/*------------------------------------------------------------------------*
 *      hid_put_data
 *------------------------------------------------------------------------*/
void
hid_put_udata(uint8_t *buf, hid_size_t len,
    struct hid_location *loc, unsigned int value)
{
        uint32_t hpos = loc->pos;
        uint32_t hsize = loc->size;
        uint64_t data;
        uint64_t mask;
        uint32_t rpos;
        uint8_t n;

        DPRINTFN(11, "hid_put_data: loc %d/%d = %u\n", hpos, hsize, value);

        /* Range check and limit */
        if (hsize == 0)
                return;
        if (hsize > 32)
                hsize = 32;

        /* Put data in a safe way */    
        rpos = (hpos / 8);
        n = (hsize + 7) / 8;
        data = ((uint64_t)value) << (hpos % 8);
        mask = ((1ULL << hsize) - 1ULL) << (hpos % 8);
        rpos += n;
        while (n--) {
                rpos--;
                if (rpos < len) {
                        buf[rpos] &= ~(mask >> (8 * n));
                        buf[rpos] |= (data >> (8 * n));
                }
        }
}

/*------------------------------------------------------------------------*
 *      hid_is_collection
 *------------------------------------------------------------------------*/
int
hid_is_collection(const void *desc, hid_size_t size, int32_t usage)
{
        struct hid_data *hd;
        struct hid_item hi;
        int err;

        hd = hid_start_parse(desc, size, 0);
        if (hd == NULL)
                return (0);

        while ((err = hid_get_item(hd, &hi))) {
                 if (hi.kind == hid_collection &&
                     hi.usage == usage)
                        break;
        }
        hid_end_parse(hd);
        return (err);
}

/*------------------------------------------------------------------------*
 * calculate HID item resolution. unit/mm for distances, unit/rad for angles
 *------------------------------------------------------------------------*/
int32_t
hid_item_resolution(struct hid_item *hi)
{
        /*
         * hid unit scaling table according to HID Usage Table Review
         * Request 39 Tbl 17 http://www.usb.org/developers/hidpage/HUTRR39b.pdf
         */
        static const int64_t scale[0x10][2] = {
            [0x00] = { 1, 1 },
            [0x01] = { 1, 10 },
            [0x02] = { 1, 100 },
            [0x03] = { 1, 1000 },
            [0x04] = { 1, 10000 },
            [0x05] = { 1, 100000 },
            [0x06] = { 1, 1000000 },
            [0x07] = { 1, 10000000 },
            [0x08] = { 100000000, 1 },
            [0x09] = { 10000000, 1 },
            [0x0A] = { 1000000, 1 },
            [0x0B] = { 100000, 1 },
            [0x0C] = { 10000, 1 },
            [0x0D] = { 1000, 1 },
            [0x0E] = { 100, 1 },
            [0x0F] = { 10, 1 },
        };
        int64_t logical_size;
        int64_t physical_size;
        int64_t multiplier;
        int64_t divisor;
        int64_t resolution;

        switch (hi->unit) {
        case HUM_CENTIMETER:
                multiplier = 1;
                divisor = 10;
                break;
        case HUM_INCH:
        case HUM_INCH_EGALAX:
                multiplier = 10;
                divisor = 254;
                break;
        case HUM_RADIAN:
                multiplier = 1;
                divisor = 1;
                break;
        case HUM_DEGREE:
                multiplier = 573;
                divisor = 10;
                break;
        default:
                return (0);
        }

        if ((hi->logical_maximum <= hi->logical_minimum) ||
            (hi->physical_maximum <= hi->physical_minimum) ||
            (hi->unit_exponent < 0) || (hi->unit_exponent >= nitems(scale)))
                return (0);

        logical_size = (int64_t)hi->logical_maximum -
            (int64_t)hi->logical_minimum;
        physical_size = (int64_t)hi->physical_maximum -
            (int64_t)hi->physical_minimum;
        /* Round to ceiling */
        resolution = logical_size * multiplier * scale[hi->unit_exponent][0] /
            (physical_size * divisor * scale[hi->unit_exponent][1]);

        if (resolution > INT32_MAX)
                return (0);

        return (resolution);
}

/*------------------------------------------------------------------------*
 *      hid_is_mouse
 *
 * This function will decide if a USB descriptor belongs to a USB mouse.
 *
 * Return values:
 * Zero: Not a USB mouse.
 * Else: Is a USB mouse.
 *------------------------------------------------------------------------*/
int
hid_is_mouse(const void *d_ptr, uint16_t d_len)
{
        struct hid_data *hd;
        struct hid_item hi;
        int mdepth;
        int found;

        hd = hid_start_parse(d_ptr, d_len, 1 << hid_input);
        if (hd == NULL)
                return (0);

        mdepth = 0;
        found = 0;

        while (hid_get_item(hd, &hi)) {
                switch (hi.kind) {
                case hid_collection:
                        if (mdepth != 0)
                                mdepth++;
                        else if (hi.collection == 1 &&
                             hi.usage ==
                              HID_USAGE2(HUP_GENERIC_DESKTOP, HUG_MOUSE))
                                mdepth++;
                        break;
                case hid_endcollection:
                        if (mdepth != 0)
                                mdepth--;
                        break;
                case hid_input:
                        if (mdepth == 0)
                                break;
                        if (hi.usage ==
                             HID_USAGE2(HUP_GENERIC_DESKTOP, HUG_X) &&
                            (hi.flags & (HIO_CONST|HIO_RELATIVE)) == HIO_RELATIVE)
                                found++;
                        if (hi.usage ==
                             HID_USAGE2(HUP_GENERIC_DESKTOP, HUG_Y) &&
                            (hi.flags & (HIO_CONST|HIO_RELATIVE)) == HIO_RELATIVE)
                                found++;
                        break;
                default:
                        break;
                }
        }
        hid_end_parse(hd);
        return (found);
}

/*------------------------------------------------------------------------*
 *      hid_is_keyboard
 *
 * This function will decide if a USB descriptor belongs to a USB keyboard.
 *
 * Return values:
 * Zero: Not a USB keyboard.
 * Else: Is a USB keyboard.
 *------------------------------------------------------------------------*/
int
hid_is_keyboard(const void *d_ptr, uint16_t d_len)
{
        if (hid_is_collection(d_ptr, d_len,
            HID_USAGE2(HUP_GENERIC_DESKTOP, HUG_KEYBOARD)))
                return (1);
        return (0);
}

/*------------------------------------------------------------------------*
 *      hid_test_quirk - test a device for a given quirk
 *
 * Return values:
 * false: The HID device does not have the given quirk.
 * true: The HID device has the given quirk.
 *------------------------------------------------------------------------*/
bool
hid_test_quirk(const struct hid_device_info *dev_info, uint16_t quirk)
{
        bool found;
        uint8_t x;

        if (quirk == HQ_NONE)
                return (false);

        /* search the automatic per device quirks first */
        for (x = 0; x != HID_MAX_AUTO_QUIRK; x++) {
                if (dev_info->autoQuirk[x] == quirk)
                        return (true);
        }

        /* search global quirk table, if any */
        found = (hid_test_quirk_p) (dev_info, quirk);

        return (found);
}

static bool
hid_test_quirk_w(const struct hid_device_info *dev_info, uint16_t quirk)
{
        return (false);                 /* no match */
}

int
hid_add_dynamic_quirk(struct hid_device_info *dev_info, uint16_t quirk)
{
        uint8_t x;

        for (x = 0; x != HID_MAX_AUTO_QUIRK; x++) {
                if (dev_info->autoQuirk[x] == 0 ||
                    dev_info->autoQuirk[x] == quirk) {
                        dev_info->autoQuirk[x] = quirk;
                        return (0);     /* success */
                }
        }
        return (ENOSPC);
}

void
hid_quirk_unload(void *arg)
{
        /* reset function pointer */
        hid_test_quirk_p = &hid_test_quirk_w;
#ifdef NOT_YET
        hidquirk_ioctl_p = &hidquirk_ioctl_w;
#endif

        /* wait for CPU to exit the loaded functions, if any */

        /* XXX this is a tradeoff */

        pause("WAIT", hz);
}

int
hid_intr_start(device_t dev)
{
        return (HID_INTR_START(device_get_parent(dev), dev));
}

int
hid_intr_stop(device_t dev)
{
        return (HID_INTR_STOP(device_get_parent(dev), dev));
}

void
hid_intr_poll(device_t dev)
{
        HID_INTR_POLL(device_get_parent(dev), dev);
}

int
hid_get_rdesc(device_t dev, void *data, hid_size_t len)
{
        return (HID_GET_RDESC(device_get_parent(dev), dev, data, len));
}

int
hid_read(device_t dev, void *data, hid_size_t maxlen, hid_size_t *actlen)
{
        return (HID_READ(device_get_parent(dev), dev, data, maxlen, actlen));
}

int
hid_write(device_t dev, const void *data, hid_size_t len)
{
        return (HID_WRITE(device_get_parent(dev), dev, data, len));
}

int
hid_get_report(device_t dev, void *data, hid_size_t maxlen, hid_size_t *actlen,
    uint8_t type, uint8_t id)
{
        return (HID_GET_REPORT(device_get_parent(dev), dev, data, maxlen,
            actlen, type, id));
}

int
hid_set_report(device_t dev, const void *data, hid_size_t len, uint8_t type,
    uint8_t id)
{
        return (HID_SET_REPORT(device_get_parent(dev), dev, data, len, type,
            id));
}

int
hid_set_idle(device_t dev, uint16_t duration, uint8_t id)
{
        return (HID_SET_IDLE(device_get_parent(dev), dev, duration, id));
}

int
hid_set_protocol(device_t dev, uint16_t protocol)
{
        return (HID_SET_PROTOCOL(device_get_parent(dev), dev, protocol));
}

int
hid_ioctl(device_t dev, unsigned long cmd, uintptr_t data)
{
        return (HID_IOCTL(device_get_parent(dev), dev, cmd, data));
}

MODULE_VERSION(hid, 1);