/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2002 Orion Hodson <orion@freebsd.org>
 * Portions of this code derived from via82c686.c:
 *      Copyright (c) 2000 David Jones <dej@ox.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
 */

/*
 * Credits due to:
 *
 * Grzybowski Rafal, Russell Davies, Mark Handley, Daniel O'Connor for
 * comments, machine time, testing patches, and patience.  VIA for
 * providing specs.  ALSA for helpful comments and some register poke
 * ordering.
 */

#ifdef HAVE_KERNEL_OPTION_HEADERS
#include "opt_snd.h"
#endif

#include <dev/sound/pcm/sound.h>
#include <dev/sound/pcm/ac97.h>

#include <dev/pci/pcireg.h>
#include <dev/pci/pcivar.h>
#include <sys/sysctl.h>

#include <dev/sound/pci/via8233.h>

#define VIA8233_PCI_ID 0x30591106

#define VIA8233_REV_ID_8233PRE  0x10
#define VIA8233_REV_ID_8233C    0x20
#define VIA8233_REV_ID_8233     0x30
#define VIA8233_REV_ID_8233A    0x40
#define VIA8233_REV_ID_8235     0x50
#define VIA8233_REV_ID_8237     0x60
#define VIA8233_REV_ID_8251     0x70

#define SEGS_PER_CHAN   2                       /* Segments per channel */
#define NDXSCHANS       4                       /* No of DXS channels */
#define NMSGDCHANS      1                       /* No of multichannel SGD */
#define NWRCHANS        1                       /* No of write channels */
#define NCHANS          (NWRCHANS + NDXSCHANS + NMSGDCHANS)
#define NSEGS           NCHANS * SEGS_PER_CHAN  /* Segments in SGD table */
#define VIA_SEGS_MIN            2
#define VIA_SEGS_MAX            64
#define VIA_SEGS_DEFAULT        2
#define VIA_BLK_MIN             32
#define VIA_BLK_ALIGN           (~(VIA_BLK_MIN - 1))

#define VIA_DEFAULT_BUFSZ       0x1000

/* we rely on this struct being packed to 64 bits */
struct via_dma_op {
        volatile uint32_t ptr;
        volatile uint32_t flags;
#define VIA_DMAOP_EOL         0x80000000
#define VIA_DMAOP_FLAG        0x40000000
#define VIA_DMAOP_STOP        0x20000000
#define VIA_DMAOP_COUNT(x)    ((x)&0x00FFFFFF)
};

struct via_info;

struct via_chinfo {
        struct via_info *parent;
        struct pcm_channel *channel;
        struct snd_dbuf *buffer;
        struct via_dma_op *sgd_table;
        bus_addr_t sgd_addr;
        int dir, rbase, active;
        unsigned int blksz, blkcnt;
        unsigned int ptr, prevptr;
};

struct via_info {
        device_t dev;

        bus_space_tag_t st;
        bus_space_handle_t sh;
        bus_dma_tag_t parent_dmat;
        bus_dma_tag_t sgd_dmat;
        bus_dmamap_t sgd_dmamap;
        bus_addr_t sgd_addr;

        struct resource *reg, *irq;
        int regid, irqid;
        void *ih;
        struct ac97_info *codec;

        unsigned int bufsz, blkcnt;
        int dxs_src, dma_eol_wake;

        struct via_chinfo pch[NDXSCHANS + NMSGDCHANS];
        struct via_chinfo rch[NWRCHANS];
        struct via_dma_op *sgd_table;
        uint16_t codec_caps;
        uint16_t n_dxs_registered;
        int play_num, rec_num;
        struct mtx lock;
        struct callout poll_timer;
        int poll_ticks, polling;
};

static uint32_t via_fmt[] = {
        SND_FORMAT(AFMT_U8, 1, 0),
        SND_FORMAT(AFMT_U8, 2, 0),
        SND_FORMAT(AFMT_S16_LE, 1, 0),
        SND_FORMAT(AFMT_S16_LE, 2, 0),
        0
};

static struct pcmchan_caps via_vracaps = { 4000, 48000, via_fmt, 0 };
static struct pcmchan_caps via_caps = { 48000, 48000, via_fmt, 0 };

static __inline int
via_chan_active(struct via_info *via)
{
        int i, ret = 0;

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

        for (i = 0; i < NDXSCHANS + NMSGDCHANS; i++)
                ret += via->pch[i].active;

        for (i = 0; i < NWRCHANS; i++)
                ret += via->rch[i].active;

        return (ret);
}

static int
sysctl_via8233_spdif_enable(SYSCTL_HANDLER_ARGS)
{
        struct via_info *via;
        device_t dev;
        uint32_t r;
        int err, new_en;

        dev = oidp->oid_arg1;
        via = pcm_getdevinfo(dev);
        mtx_lock(&via->lock);
        r = pci_read_config(dev, VIA_PCI_SPDIF, 1);
        mtx_unlock(&via->lock);
        new_en = (r & VIA_SPDIF_EN) ? 1 : 0;
        err = sysctl_handle_int(oidp, &new_en, 0, req);

        if (err || req->newptr == NULL)
                return (err);
        if (new_en < 0 || new_en > 1)
                return (EINVAL);

        if (new_en)
                r |= VIA_SPDIF_EN;
        else
                r &= ~VIA_SPDIF_EN;
        mtx_lock(&via->lock);
        pci_write_config(dev, VIA_PCI_SPDIF, r, 1);
        mtx_unlock(&via->lock);

        return (0);
}

static int
sysctl_via8233_dxs_src(SYSCTL_HANDLER_ARGS)
{
        struct via_info *via;
        device_t dev;
        int err, val;

        dev = oidp->oid_arg1;
        via = pcm_getdevinfo(dev);
        mtx_lock(&via->lock);
        val = via->dxs_src;
        mtx_unlock(&via->lock);
        err = sysctl_handle_int(oidp, &val, 0, req);

        if (err || req->newptr == NULL)
                return (err);
        if (val < 0 || val > 1)
                return (EINVAL);

        mtx_lock(&via->lock);
        via->dxs_src = val;
        mtx_unlock(&via->lock);

        return (0);
}

static int
sysctl_via_polling(SYSCTL_HANDLER_ARGS)
{
        struct via_info *via;
        device_t dev;
        int err, val;

        dev = oidp->oid_arg1;
        via = pcm_getdevinfo(dev);
        if (via == NULL)
                return (EINVAL);
        mtx_lock(&via->lock);
        val = via->polling;
        mtx_unlock(&via->lock);
        err = sysctl_handle_int(oidp, &val, 0, req);

        if (err || req->newptr == NULL)
                return (err);
        if (val < 0 || val > 1)
                return (EINVAL);

        mtx_lock(&via->lock);
        if (val != via->polling) {
                if (via_chan_active(via) != 0)
                        err = EBUSY;
                else if (val == 0)
                        via->polling = 0;
                else
                        via->polling = 1;
        }
        mtx_unlock(&via->lock);

        return (err);
}

static void
via_init_sysctls(device_t dev)
{
        /* XXX: an user should be able to set this with a control tool,
           if not done before 7.0-RELEASE, this needs to be converted to
           a device specific sysctl "dev.pcm.X.yyy" via device_get_sysctl_*()
           as discussed on multimedia@ in msg-id <861wujij2q.fsf@xps.des.no> */
        SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
            SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO,
            "spdif_enabled", CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
            dev, sizeof(dev), sysctl_via8233_spdif_enable, "I",
            "Enable S/PDIF output on primary playback channel");
        SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
            SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO,
            "dxs_src", CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
            dev, sizeof(dev), sysctl_via8233_dxs_src, "I",
            "Enable VIA DXS Sample Rate Converter");
        SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
            SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO,
            "polling", CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
            dev, sizeof(dev), sysctl_via_polling, "I", "Enable polling mode");
}

static __inline uint32_t
via_rd(struct via_info *via, int regno, int size)
{
        switch (size) {
        case 1:
                return (bus_space_read_1(via->st, via->sh, regno));
        case 2:
                return (bus_space_read_2(via->st, via->sh, regno));
        case 4:
                return (bus_space_read_4(via->st, via->sh, regno));
        default:
                return (0xFFFFFFFF);
        }
}

static __inline void
via_wr(struct via_info *via, int regno, uint32_t data, int size)
{

        switch (size) {
        case 1:
                bus_space_write_1(via->st, via->sh, regno, data);
                break;
        case 2:
                bus_space_write_2(via->st, via->sh, regno, data);
                break;
        case 4:
                bus_space_write_4(via->st, via->sh, regno, data);
                break;
        }
}

/* -------------------------------------------------------------------- */
/* Codec interface */

static int
via_waitready_codec(struct via_info *via)
{
        int i;

        /* poll until codec not busy */
        for (i = 0; i < 1000; i++) {
                if ((via_rd(via, VIA_AC97_CONTROL, 4) & VIA_AC97_BUSY) == 0)
                        return (0);
                DELAY(1);
        }
        device_printf(via->dev, "%s: codec busy\n", __func__);
        return (1);
}

static int
via_waitvalid_codec(struct via_info *via)
{
        int i;

        /* poll until codec valid */
        for (i = 0; i < 1000; i++) {
                if (via_rd(via, VIA_AC97_CONTROL, 4) & VIA_AC97_CODEC00_VALID)
                        return (0);
                DELAY(1);
        }
        device_printf(via->dev, "%s: codec invalid\n", __func__);
        return (1);
}

static int
via_write_codec(kobj_t obj, void *addr, int reg, uint32_t val)
{
        struct via_info *via = addr;

        if (via_waitready_codec(via))
                return (-1);

        via_wr(via, VIA_AC97_CONTROL,
               VIA_AC97_CODEC00_VALID | VIA_AC97_INDEX(reg) |
               VIA_AC97_DATA(val), 4);

        return (0);
}

static int
via_read_codec(kobj_t obj, void *addr, int reg)
{
        struct via_info *via = addr;

        if (via_waitready_codec(via))
                return (-1);

        via_wr(via, VIA_AC97_CONTROL, VIA_AC97_CODEC00_VALID |
            VIA_AC97_READ | VIA_AC97_INDEX(reg), 4);

        if (via_waitready_codec(via))
                return (-1);

        if (via_waitvalid_codec(via))
                return (-1);

        return (via_rd(via, VIA_AC97_CONTROL, 2));
}

static kobj_method_t via_ac97_methods[] = {
        KOBJMETHOD(ac97_read,           via_read_codec),
        KOBJMETHOD(ac97_write,          via_write_codec),
        KOBJMETHOD_END
};
AC97_DECLARE(via_ac97);

/* -------------------------------------------------------------------- */

static int
via_buildsgdt(struct via_chinfo *ch)
{
        uint32_t phys_addr, flag;
        int i;

        phys_addr = ch->buffer->buf_addr;

        for (i = 0; i < ch->blkcnt; i++) {
                flag = (i == ch->blkcnt - 1) ? VIA_DMAOP_EOL : VIA_DMAOP_FLAG;
                ch->sgd_table[i].ptr = phys_addr + (i * ch->blksz);
                ch->sgd_table[i].flags = flag | ch->blksz;
        }

        return (0);
}

/* -------------------------------------------------------------------- */
/* Format setting functions */

static int
via8233wr_setformat(kobj_t obj, void *data, uint32_t format)
{
        struct via_chinfo *ch = data;
        struct via_info *via = ch->parent;

        uint32_t f = WR_FORMAT_STOP_INDEX;

        if (AFMT_CHANNEL(format) > 1)
                f |= WR_FORMAT_STEREO;
        if (format & AFMT_S16_LE)
                f |= WR_FORMAT_16BIT;
        mtx_lock(&via->lock);
        via_wr(via, VIA_WR0_FORMAT, f, 4);
        mtx_unlock(&via->lock);

        return (0);
}

static int
via8233dxs_setformat(kobj_t obj, void *data, uint32_t format)
{
        struct via_chinfo *ch = data;
        struct via_info *via = ch->parent;
        uint32_t r, v;

        r = ch->rbase + VIA8233_RP_DXS_RATEFMT;
        mtx_lock(&via->lock);
        v = via_rd(via, r, 4);

        v &= ~(VIA8233_DXS_RATEFMT_STEREO | VIA8233_DXS_RATEFMT_16BIT);
        if (AFMT_CHANNEL(format) > 1)
                v |= VIA8233_DXS_RATEFMT_STEREO;
        if (format & AFMT_16BIT)
                v |= VIA8233_DXS_RATEFMT_16BIT;
        via_wr(via, r, v, 4);
        mtx_unlock(&via->lock);

        return (0);
}

static int
via8233msgd_setformat(kobj_t obj, void *data, uint32_t format)
{
        struct via_chinfo *ch = data;
        struct via_info *via = ch->parent;

        uint32_t s = 0xff000000;
        uint8_t  v = (format & AFMT_S16_LE) ? MC_SGD_16BIT : MC_SGD_8BIT;

        if (AFMT_CHANNEL(format) > 1) {
                v |= MC_SGD_CHANNELS(2);
                s |= SLOT3(1) | SLOT4(2);
        } else {
                v |= MC_SGD_CHANNELS(1);
                s |= SLOT3(1) | SLOT4(1);
        }

        mtx_lock(&via->lock);
        via_wr(via, VIA_MC_SLOT_SELECT, s, 4);
        via_wr(via, VIA_MC_SGD_FORMAT, v, 1);
        mtx_unlock(&via->lock);

        return (0);
}

/* -------------------------------------------------------------------- */
/* Speed setting functions */

static uint32_t
via8233wr_setspeed(kobj_t obj, void *data, uint32_t speed)
{
        struct via_chinfo *ch = data;
        struct via_info *via = ch->parent;

        if (via->codec_caps & AC97_EXTCAP_VRA)
                return (ac97_setrate(via->codec, AC97_REGEXT_LADCRATE, speed));

        return (48000);
}

static uint32_t
via8233dxs_setspeed(kobj_t obj, void *data, uint32_t speed)
{
        struct via_chinfo *ch = data;
        struct via_info *via = ch->parent;
        uint32_t r, v;

        r = ch->rbase + VIA8233_RP_DXS_RATEFMT;
        mtx_lock(&via->lock);
        v = via_rd(via, r, 4) & ~VIA8233_DXS_RATEFMT_48K;

        /* Careful to avoid overflow (divide by 48 per vt8233c docs) */

        v |= VIA8233_DXS_RATEFMT_48K * (speed / 48) / (48000 / 48);
        via_wr(via, r, v, 4);
        mtx_unlock(&via->lock);

        return (speed);
}

static uint32_t
via8233msgd_setspeed(kobj_t obj, void *data, uint32_t speed)
{
        struct via_chinfo *ch = data;
        struct via_info *via = ch->parent;

        if (via->codec_caps & AC97_EXTCAP_VRA)
                return (ac97_setrate(via->codec, AC97_REGEXT_FDACRATE, speed));

        return (48000);
}

/* -------------------------------------------------------------------- */
/* Format probing functions */

static struct pcmchan_caps *
via8233wr_getcaps(kobj_t obj, void *data)
{
        struct via_chinfo *ch = data;
        struct via_info *via = ch->parent;

        /* Controlled by ac97 registers */
        if (via->codec_caps & AC97_EXTCAP_VRA)
                return (&via_vracaps);
        return (&via_caps);
}

static struct pcmchan_caps *
via8233dxs_getcaps(kobj_t obj, void *data)
{
        struct via_chinfo *ch = data;
        struct via_info *via = ch->parent;

        /*
         * Controlled by onboard registers
         *
         * Apparently, few boards can do DXS sample rate
         * conversion.
         */
        if (via->dxs_src)
                return (&via_vracaps);
        return (&via_caps);
}

static struct pcmchan_caps *
via8233msgd_getcaps(kobj_t obj, void *data)
{
        struct via_chinfo *ch = data;
        struct via_info *via = ch->parent;

        /* Controlled by ac97 registers */
        if (via->codec_caps & AC97_EXTCAP_VRA)
                return (&via_vracaps);
        return (&via_caps);
}

/* -------------------------------------------------------------------- */
/* Common functions */

static int
via8233chan_setfragments(kobj_t obj, void *data,
                                        uint32_t blksz, uint32_t blkcnt)
{
        struct via_chinfo *ch = data;
        struct via_info *via = ch->parent;

        blksz &= VIA_BLK_ALIGN;

        if (blksz > (ch->buffer->maxsize / VIA_SEGS_MIN))
                blksz = ch->buffer->maxsize / VIA_SEGS_MIN;
        if (blksz < VIA_BLK_MIN)
                blksz = VIA_BLK_MIN;
        if (blkcnt > VIA_SEGS_MAX)
                blkcnt = VIA_SEGS_MAX;
        if (blkcnt < VIA_SEGS_MIN)
                blkcnt = VIA_SEGS_MIN;

        while ((blksz * blkcnt) > ch->buffer->maxsize) {
                if ((blkcnt >> 1) >= VIA_SEGS_MIN)
                        blkcnt >>= 1;
                else if ((blksz >> 1) >= VIA_BLK_MIN)
                        blksz >>= 1;
                else
                        break;
        }

        if ((ch->buffer->blksz != blksz ||
            ch->buffer->blkcnt != blkcnt) &&
            sndbuf_resize(ch->buffer, blkcnt, blksz) != 0)
                device_printf(via->dev, "%s: failed blksz=%u blkcnt=%u\n",
                    __func__, blksz, blkcnt);

        ch->blksz = ch->buffer->blksz;
        ch->blkcnt = ch->buffer->blkcnt;

        return (0);
}

static uint32_t
via8233chan_setblocksize(kobj_t obj, void *data, uint32_t blksz)
{
        struct via_chinfo *ch = data;
        struct via_info *via = ch->parent;

        via8233chan_setfragments(obj, data, blksz, via->blkcnt);

        return (ch->blksz);
}

static uint32_t
via8233chan_getptr(kobj_t obj, void *data)
{
        struct via_chinfo *ch = data;
        struct via_info *via = ch->parent;
        uint32_t v, index, count, ptr;

        mtx_lock(&via->lock);
        if (via->polling != 0) {
                ptr = ch->ptr;
                mtx_unlock(&via->lock);
        } else {
                v = via_rd(via, ch->rbase + VIA_RP_CURRENT_COUNT, 4);
                mtx_unlock(&via->lock);
                index = v >> 24;                /* Last completed buffer */
                count = v & 0x00ffffff; /* Bytes remaining */
                ptr = (index + 1) * ch->blksz - count;
                ptr %= ch->blkcnt * ch->blksz;  /* Wrap to available space */
        }

        return (ptr);
}

static void
via8233chan_reset(struct via_info *via, struct via_chinfo *ch)
{
        via_wr(via, ch->rbase + VIA_RP_CONTROL, SGD_CONTROL_STOP, 1);
        via_wr(via, ch->rbase + VIA_RP_CONTROL, 0x00, 1);
        via_wr(via, ch->rbase + VIA_RP_STATUS,
            SGD_STATUS_EOL | SGD_STATUS_FLAG, 1);
}

/* -------------------------------------------------------------------- */
/* Channel initialization functions */

static void
via8233chan_sgdinit(struct via_info *via, struct via_chinfo *ch, int chnum)
{
        ch->sgd_table = &via->sgd_table[chnum * VIA_SEGS_MAX];
        ch->sgd_addr = via->sgd_addr + chnum * VIA_SEGS_MAX *
            sizeof(struct via_dma_op);
}

static void*
via8233wr_init(kobj_t obj, void *devinfo, struct snd_dbuf *b,
                                                struct pcm_channel *c, int dir)
{
        struct via_info *via = devinfo;
        struct via_chinfo *ch;
        int num;

        mtx_lock(&via->lock);
        num = via->rec_num++;
        ch = &via->rch[num];
        ch->parent = via;
        ch->channel = c;
        ch->buffer = b;
        ch->dir = dir;
        ch->blkcnt = via->blkcnt;
        ch->rbase = VIA_WR_BASE(num);
        via_wr(via, ch->rbase + VIA_WR_RP_SGD_FORMAT, WR_FIFO_ENABLE, 1);
        mtx_unlock(&via->lock);

        if (sndbuf_alloc(ch->buffer, via->parent_dmat, 0, via->bufsz) != 0)
                return (NULL);

        mtx_lock(&via->lock);
        via8233chan_sgdinit(via, ch, num);
        via8233chan_reset(via, ch);
        mtx_unlock(&via->lock);

        return (ch);
}

static void*
via8233dxs_init(kobj_t obj, void *devinfo, struct snd_dbuf *b,
                                                struct pcm_channel *c, int dir)
{
        struct via_info *via = devinfo;
        struct via_chinfo *ch;
        int num;

        mtx_lock(&via->lock);
        num = via->play_num++;
        ch = &via->pch[num];
        ch->parent = via;
        ch->channel = c;
        ch->buffer = b;
        ch->dir = dir;
        ch->blkcnt = via->blkcnt;

        /*
         * All cards apparently support DXS3, but not other DXS
         * channels.  We therefore want to align first DXS channel to
         * DXS3.
         */
        ch->rbase = VIA_DXS_BASE(NDXSCHANS - 1 - via->n_dxs_registered);
        via->n_dxs_registered++;
        mtx_unlock(&via->lock);

        if (sndbuf_alloc(ch->buffer, via->parent_dmat, 0, via->bufsz) != 0)
                return (NULL);

        mtx_lock(&via->lock);
        via8233chan_sgdinit(via, ch, NWRCHANS + num);
        via8233chan_reset(via, ch);
        mtx_unlock(&via->lock);

        return (ch);
}

static void*
via8233msgd_init(kobj_t obj, void *devinfo, struct snd_dbuf *b,
                                                struct pcm_channel *c, int dir)
{
        struct via_info *via = devinfo;
        struct via_chinfo *ch;
        int num;

        mtx_lock(&via->lock);
        num = via->play_num++;
        ch = &via->pch[num];
        ch->parent = via;
        ch->channel = c;
        ch->buffer = b;
        ch->dir = dir;
        ch->rbase = VIA_MC_SGD_STATUS;
        ch->blkcnt = via->blkcnt;
        mtx_unlock(&via->lock);

        if (sndbuf_alloc(ch->buffer, via->parent_dmat, 0, via->bufsz) != 0)
                return (NULL);

        mtx_lock(&via->lock);
        via8233chan_sgdinit(via, ch, NWRCHANS + num);
        via8233chan_reset(via, ch);
        mtx_unlock(&via->lock);

        return (ch);
}

static void
via8233chan_mute(struct via_info *via, struct via_chinfo *ch, int muted)
{
        if (BASE_IS_VIA_DXS_REG(ch->rbase)) {
                int r;
                muted = (muted) ? VIA8233_DXS_MUTE : 0;
                via_wr(via, ch->rbase + VIA8233_RP_DXS_LVOL, muted, 1);
                via_wr(via, ch->rbase + VIA8233_RP_DXS_RVOL, muted, 1);
                r = via_rd(via, ch->rbase + VIA8233_RP_DXS_LVOL, 1) &
                    VIA8233_DXS_MUTE;
                if (r != muted)
                        device_printf(via->dev,
                            "%s: failed to set dxs volume "
                            "(dxs base 0x%02x).\n", __func__, ch->rbase);
        }
}

static __inline int
via_poll_channel(struct via_chinfo *ch)
{
        struct via_info *via;
        uint32_t sz, delta;
        uint32_t v, index, count;
        int ptr;

        if (ch == NULL || ch->channel == NULL || ch->active == 0)
                return (0);

        via = ch->parent;
        sz = ch->blksz * ch->blkcnt;
        v = via_rd(via, ch->rbase + VIA_RP_CURRENT_COUNT, 4);
        index = v >> 24;
        count = v & 0x00ffffff;
        ptr = ((index + 1) * ch->blksz) - count;
        ptr %= sz;
        ptr &= ~(ch->blksz - 1);
        ch->ptr = ptr;
        delta = (sz + ptr - ch->prevptr) % sz;

        if (delta < ch->blksz)
                return (0);

        ch->prevptr = ptr;

        return (1);
}

static void
via_poll_callback(void *arg)
{
        struct via_info *via = arg;
        uint32_t ptrigger = 0, rtrigger = 0;
        int i;

        if (via == NULL)
                return;

        mtx_lock(&via->lock);
        if (via->polling == 0 || via_chan_active(via) == 0) {
                mtx_unlock(&via->lock);
                return;
        }

        for (i = 0; i < NDXSCHANS + NMSGDCHANS; i++)
                ptrigger |= (via_poll_channel(&via->pch[i]) != 0) ?
                    (1 << i) : 0;

        for (i = 0; i < NWRCHANS; i++)
                rtrigger |= (via_poll_channel(&via->rch[i]) != 0) ?
                    (1 << i) : 0;

        /* XXX */
        callout_reset(&via->poll_timer, 1/*via->poll_ticks*/,
            via_poll_callback, via);

        mtx_unlock(&via->lock);

        for (i = 0; i < NDXSCHANS + NMSGDCHANS; i++) {
                if (ptrigger & (1 << i))
                        chn_intr(via->pch[i].channel);
        }
        for (i = 0; i < NWRCHANS; i++) {
                if (rtrigger & (1 << i))
                        chn_intr(via->rch[i].channel);
        }
}

static int
via_poll_ticks(struct via_info *via)
{
        struct via_chinfo *ch;
        int i;
        int ret = hz;
        int pollticks;

        for (i = 0; i < NDXSCHANS + NMSGDCHANS; i++) {
                ch = &via->pch[i];
                if (ch->channel == NULL || ch->active == 0)
                        continue;
                pollticks = ((uint64_t)hz * ch->blksz) /
                    ((uint64_t)ch->buffer->align * ch->buffer->spd);
                pollticks >>= 2;
                if (pollticks > hz)
                        pollticks = hz;
                if (pollticks < 1)
                        pollticks = 1;
                if (pollticks < ret)
                        ret = pollticks;
        }

        for (i = 0; i < NWRCHANS; i++) {
                ch = &via->rch[i];
                if (ch->channel == NULL || ch->active == 0)
                        continue;
                pollticks = ((uint64_t)hz * ch->blksz) /
                    ((uint64_t)ch->buffer->align * ch->buffer->spd);
                pollticks >>= 2;
                if (pollticks > hz)
                        pollticks = hz;
                if (pollticks < 1)
                        pollticks = 1;
                if (pollticks < ret)
                        ret = pollticks;
        }

        return (ret);
}

static int
via8233chan_trigger(kobj_t obj, void* data, int go)
{
        struct via_chinfo *ch = data;
        struct via_info *via = ch->parent;
        int pollticks;

        if (!PCMTRIG_COMMON(go))
                return (0);

        mtx_lock(&via->lock);
        switch(go) {
        case PCMTRIG_START:
                via_buildsgdt(ch);
                via8233chan_mute(via, ch, 0);
                via_wr(via, ch->rbase + VIA_RP_TABLE_PTR, ch->sgd_addr, 4);
                if (via->polling != 0) {
                        ch->ptr = 0;
                        ch->prevptr = 0;
                        pollticks = ((uint64_t)hz * ch->blksz) /
                            ((uint64_t)ch->buffer->align *
                            ch->buffer->spd);
                        pollticks >>= 2;
                        if (pollticks > hz)
                                pollticks = hz;
                        if (pollticks < 1)
                                pollticks = 1;
                        if (via_chan_active(via) == 0 ||
                            pollticks < via->poll_ticks) {
                                if (bootverbose) {
                                        if (via_chan_active(via) == 0)
                                                printf("%s: pollticks=%d\n",
                                                    __func__, pollticks);
                                        else
                                                printf("%s: "
                                                    "pollticks %d -> %d\n",
                                                    __func__, via->poll_ticks,
                                                    pollticks);
                                }
                                via->poll_ticks = pollticks;
                                callout_reset(&via->poll_timer, 1,
                                    via_poll_callback, via);
                        }
                }
                via_wr(via, ch->rbase + VIA_RP_CONTROL,
                    SGD_CONTROL_START | SGD_CONTROL_AUTOSTART |
                    ((via->polling == 0) ?
                    (SGD_CONTROL_I_EOL | SGD_CONTROL_I_FLAG) : 0), 1);
                ch->active = 1;
                break;
        case PCMTRIG_STOP:
        case PCMTRIG_ABORT:
                via_wr(via, ch->rbase + VIA_RP_CONTROL, SGD_CONTROL_STOP, 1);
                via8233chan_mute(via, ch, 1);
                via8233chan_reset(via, ch);
                ch->active = 0;
                if (via->polling != 0) {
                        if (via_chan_active(via) == 0) {
                                callout_stop(&via->poll_timer);
                                via->poll_ticks = 1;
                        } else {
                                pollticks = via_poll_ticks(via);
                                if (pollticks > via->poll_ticks) {
                                        if (bootverbose)
                                                printf("%s: pollticks "
                                                    "%d -> %d\n",
                                                    __func__, via->poll_ticks,
                                                    pollticks);
                                        via->poll_ticks = pollticks;
                                        callout_reset(&via->poll_timer,
                                            1, via_poll_callback,
                                            via);
                                }
                        }
                }
                break;
        default:
                break;
        }
        mtx_unlock(&via->lock);
        return (0);
}

static kobj_method_t via8233wr_methods[] = {
        KOBJMETHOD(channel_init,                via8233wr_init),
        KOBJMETHOD(channel_setformat,           via8233wr_setformat),
        KOBJMETHOD(channel_setspeed,            via8233wr_setspeed),
        KOBJMETHOD(channel_getcaps,             via8233wr_getcaps),
        KOBJMETHOD(channel_setblocksize,        via8233chan_setblocksize),
        KOBJMETHOD(channel_setfragments,        via8233chan_setfragments),
        KOBJMETHOD(channel_trigger,             via8233chan_trigger),
        KOBJMETHOD(channel_getptr,              via8233chan_getptr),
        KOBJMETHOD_END
};
CHANNEL_DECLARE(via8233wr);

static kobj_method_t via8233dxs_methods[] = {
        KOBJMETHOD(channel_init,                via8233dxs_init),
        KOBJMETHOD(channel_setformat,           via8233dxs_setformat),
        KOBJMETHOD(channel_setspeed,            via8233dxs_setspeed),
        KOBJMETHOD(channel_getcaps,             via8233dxs_getcaps),
        KOBJMETHOD(channel_setblocksize,        via8233chan_setblocksize),
        KOBJMETHOD(channel_setfragments,        via8233chan_setfragments),
        KOBJMETHOD(channel_trigger,             via8233chan_trigger),
        KOBJMETHOD(channel_getptr,              via8233chan_getptr),
        KOBJMETHOD_END
};
CHANNEL_DECLARE(via8233dxs);

static kobj_method_t via8233msgd_methods[] = {
        KOBJMETHOD(channel_init,                via8233msgd_init),
        KOBJMETHOD(channel_setformat,           via8233msgd_setformat),
        KOBJMETHOD(channel_setspeed,            via8233msgd_setspeed),
        KOBJMETHOD(channel_getcaps,             via8233msgd_getcaps),
        KOBJMETHOD(channel_setblocksize,        via8233chan_setblocksize),
        KOBJMETHOD(channel_setfragments,        via8233chan_setfragments),
        KOBJMETHOD(channel_trigger,             via8233chan_trigger),
        KOBJMETHOD(channel_getptr,              via8233chan_getptr),
        KOBJMETHOD_END
};
CHANNEL_DECLARE(via8233msgd);

/* -------------------------------------------------------------------- */

static void
via_intr(void *p)
{
        struct via_info *via = p;
        uint32_t ptrigger = 0, rtrigger = 0;
        int i, reg, stat;

        mtx_lock(&via->lock);
        if (via->polling != 0) {
                mtx_unlock(&via->lock);
                return;
        }
        /* Poll playback channels */
        for (i = 0; i < NDXSCHANS + NMSGDCHANS; i++) {
                if (via->pch[i].channel == NULL || via->pch[i].active == 0)
                        continue;
                reg = via->pch[i].rbase + VIA_RP_STATUS;
                stat = via_rd(via, reg, 1);
                if (stat & SGD_STATUS_INTR) {
                        if (via->dma_eol_wake && ((stat & SGD_STATUS_EOL) ||
                            !(stat & SGD_STATUS_ACTIVE)))
                                via_wr(via, via->pch[i].rbase + VIA_RP_CONTROL,
                                    SGD_CONTROL_START | SGD_CONTROL_AUTOSTART |
                                    SGD_CONTROL_I_EOL | SGD_CONTROL_I_FLAG, 1);
                        via_wr(via, reg, stat, 1);
                        ptrigger |= 1 << i;
                }
        }
        /* Poll record channels */
        for (i = 0; i < NWRCHANS; i++) {
                if (via->rch[i].channel == NULL || via->rch[i].active == 0)
                        continue;
                reg = via->rch[i].rbase + VIA_RP_STATUS;
                stat = via_rd(via, reg, 1);
                if (stat & SGD_STATUS_INTR) {
                        if (via->dma_eol_wake && ((stat & SGD_STATUS_EOL) ||
                            !(stat & SGD_STATUS_ACTIVE)))
                                via_wr(via, via->rch[i].rbase + VIA_RP_CONTROL,
                                    SGD_CONTROL_START | SGD_CONTROL_AUTOSTART |
                                    SGD_CONTROL_I_EOL | SGD_CONTROL_I_FLAG, 1);
                        via_wr(via, reg, stat, 1);
                        rtrigger |= 1 << i;
                }
        }
        mtx_unlock(&via->lock);

        for (i = 0; i < NDXSCHANS + NMSGDCHANS; i++) {
                if (ptrigger & (1 << i))
                        chn_intr(via->pch[i].channel);
        }
        for (i = 0; i < NWRCHANS; i++) {
                if (rtrigger & (1 << i))
                        chn_intr(via->rch[i].channel);
        }
}

/*
 *  Probe and attach the card
 */
static int
via_probe(device_t dev)
{
        switch(pci_get_devid(dev)) {
        case VIA8233_PCI_ID:
                switch(pci_get_revid(dev)) {
                case VIA8233_REV_ID_8233PRE:
                        device_set_desc(dev, "VIA VT8233 (pre)");
                        return (BUS_PROBE_DEFAULT);
                case VIA8233_REV_ID_8233C:
                        device_set_desc(dev, "VIA VT8233C");
                        return (BUS_PROBE_DEFAULT);
                case VIA8233_REV_ID_8233:
                        device_set_desc(dev, "VIA VT8233");
                        return (BUS_PROBE_DEFAULT);
                case VIA8233_REV_ID_8233A:
                        device_set_desc(dev, "VIA VT8233A");
                        return (BUS_PROBE_DEFAULT);
                case VIA8233_REV_ID_8235:
                        device_set_desc(dev, "VIA VT8235");
                        return (BUS_PROBE_DEFAULT);
                case VIA8233_REV_ID_8237:
                        device_set_desc(dev, "VIA VT8237");
                        return (BUS_PROBE_DEFAULT);
                case VIA8233_REV_ID_8251:
                        device_set_desc(dev, "VIA VT8251");
                        return (BUS_PROBE_DEFAULT);
                default:
                        device_set_desc(dev, "VIA VT8233X");    /* Unknown */
                        return (BUS_PROBE_DEFAULT);
                }
        }
        return (ENXIO);
}

static void
dma_cb(void *p, bus_dma_segment_t *bds, int a, int b)
{
        struct via_info *via = (struct via_info *)p;
        via->sgd_addr = bds->ds_addr;
}

static int
via_chip_init(device_t dev)
{
        uint32_t data, cnt;

        /* Wake up and reset AC97 if necessary */
        data = pci_read_config(dev, VIA_PCI_ACLINK_STAT, 1);

        if ((data & VIA_PCI_ACLINK_C00_READY) == 0) {
                /* Cold reset per ac97r2.3 spec (page 95) */
                /* Assert low */
                pci_write_config(dev, VIA_PCI_ACLINK_CTRL,
                    VIA_PCI_ACLINK_EN, 1);
                /* Wait T_rst_low */
                DELAY(100);
                /* Assert high */
                pci_write_config(dev, VIA_PCI_ACLINK_CTRL,
                    VIA_PCI_ACLINK_EN | VIA_PCI_ACLINK_NRST, 1);
                /* Wait T_rst2clk */
                DELAY(5);
                /* Assert low */
                pci_write_config(dev, VIA_PCI_ACLINK_CTRL,
                    VIA_PCI_ACLINK_EN, 1);
        } else {
                /* Warm reset */
                /* Force no sync */
                pci_write_config(dev, VIA_PCI_ACLINK_CTRL,
                    VIA_PCI_ACLINK_EN, 1);
                DELAY(100);
                /* Sync */
                pci_write_config(dev, VIA_PCI_ACLINK_CTRL,
                    VIA_PCI_ACLINK_EN | VIA_PCI_ACLINK_SYNC, 1);
                /* Wait T_sync_high */
                DELAY(5);
                /* Force no sync */
                pci_write_config(dev, VIA_PCI_ACLINK_CTRL,
                    VIA_PCI_ACLINK_EN, 1);
                /* Wait T_sync2clk */
                DELAY(5);
        }

        /* Power everything up */
        pci_write_config(dev, VIA_PCI_ACLINK_CTRL, VIA_PCI_ACLINK_DESIRED, 1);

        /* Wait for codec to become ready (largest reported delay 310ms) */
        for (cnt = 0; cnt < 2000; cnt++) {
                data = pci_read_config(dev, VIA_PCI_ACLINK_STAT, 1);
                if (data & VIA_PCI_ACLINK_C00_READY)
                        return (0);
                DELAY(5000);
        }
        device_printf(dev, "primary codec not ready (cnt = 0x%02x)\n", cnt);
        return (ENXIO);
}

static int
via_attach(device_t dev)
{
        struct via_info *via = NULL;
        char status[SND_STATUSLEN];
        int i, via_dxs_disabled, via_dxs_src, via_dxs_chnum, via_sgd_chnum;
        int nsegs;
        uint32_t revid;

        via = malloc(sizeof *via, M_DEVBUF, M_WAITOK | M_ZERO);
        mtx_init(&via->lock, device_get_nameunit(dev), "snd_via8233 softc",
            MTX_DEF);
        via->dev = dev;

        callout_init(&via->poll_timer, 1);
        via->poll_ticks = 1;

        if (resource_int_value(device_get_name(dev),
            device_get_unit(dev), "polling", &i) == 0 && i != 0)
                via->polling = 1;
        else
                via->polling = 0;

        pci_set_powerstate(dev, PCI_POWERSTATE_D0);
        pci_enable_busmaster(dev);

        via->regid = PCIR_BAR(0);
        via->reg = bus_alloc_resource_any(dev, SYS_RES_IOPORT, &via->regid,
                                          RF_ACTIVE);
        if (!via->reg) {
                device_printf(dev, "cannot allocate bus resource.");
                goto bad;
        }
        via->st = rman_get_bustag(via->reg);
        via->sh = rman_get_bushandle(via->reg);

        via->irqid = 0;
        via->irq = bus_alloc_resource_any(dev, SYS_RES_IRQ, &via->irqid,
            RF_ACTIVE | RF_SHAREABLE);
        if (!via->irq ||
            snd_setup_intr(dev, via->irq, INTR_MPSAFE,
            via_intr, via, &via->ih)) {
                device_printf(dev, "unable to map interrupt\n");
                goto bad;
        }

        via->bufsz = pcm_getbuffersize(dev, 4096, VIA_DEFAULT_BUFSZ, 65536);
        if (resource_int_value(device_get_name(dev),
            device_get_unit(dev), "blocksize", &i) == 0 && i > 0) {
                i &= VIA_BLK_ALIGN;
                if (i < VIA_BLK_MIN)
                        i = VIA_BLK_MIN;
                via->blkcnt = via->bufsz / i;
                i = 0;
                while (via->blkcnt >> i)
                        i++;
                via->blkcnt = 1 << (i - 1);
                if (via->blkcnt < VIA_SEGS_MIN)
                        via->blkcnt = VIA_SEGS_MIN;
                else if (via->blkcnt > VIA_SEGS_MAX)
                        via->blkcnt = VIA_SEGS_MAX;

        } else
                via->blkcnt = VIA_SEGS_DEFAULT;

        revid = pci_get_revid(dev);

        /*
         * VIA8251 lost its interrupt after DMA EOL, and need
         * a gentle spank on its face within interrupt handler.
         */
        if (revid == VIA8233_REV_ID_8251)
                via->dma_eol_wake = 1;
        else
                via->dma_eol_wake = 0;

        /*
         * Decide whether DXS had to be disabled or not
         */
        if (revid == VIA8233_REV_ID_8233A) {
                /*
                 * DXS channel is disabled.  Reports from multiple users
                 * that it plays at half-speed.  Do not see this behaviour
                 * on available 8233C or when emulating 8233A register set
                 * on 8233C (either with or without ac97 VRA).
                 */
                via_dxs_disabled = 1;
        } else if (resource_int_value(device_get_name(dev),
            device_get_unit(dev), "via_dxs_disabled",
            &via_dxs_disabled) == 0)
                via_dxs_disabled = (via_dxs_disabled > 0) ? 1 : 0;
        else
                via_dxs_disabled = 0;

        if (via_dxs_disabled) {
                via_dxs_chnum = 0;
                via_sgd_chnum = 1;
        } else {
                if (resource_int_value(device_get_name(dev),
                    device_get_unit(dev), "via_dxs_channels",
                    &via_dxs_chnum) != 0)
                        via_dxs_chnum = NDXSCHANS;
                if (resource_int_value(device_get_name(dev),
                    device_get_unit(dev), "via_sgd_channels",
                    &via_sgd_chnum) != 0)
                        via_sgd_chnum = NMSGDCHANS;
        }
        if (via_dxs_chnum > NDXSCHANS)
                via_dxs_chnum = NDXSCHANS;
        else if (via_dxs_chnum < 0)
                via_dxs_chnum = 0;
        if (via_sgd_chnum > NMSGDCHANS)
                via_sgd_chnum = NMSGDCHANS;
        else if (via_sgd_chnum < 0)
                via_sgd_chnum = 0;
        if (via_dxs_chnum + via_sgd_chnum < 1) {
                /* Minimalist ? */
                via_dxs_chnum = 1;
                via_sgd_chnum = 0;
        }
        if (via_dxs_chnum > 0 && resource_int_value(device_get_name(dev),
            device_get_unit(dev), "via_dxs_src", &via_dxs_src) == 0)
                via->dxs_src = (via_dxs_src > 0) ? 1 : 0;
        else
                via->dxs_src = 0;

        nsegs = (via_dxs_chnum + via_sgd_chnum + NWRCHANS) * VIA_SEGS_MAX;

        /* DMA tag for buffers */
        if (bus_dma_tag_create(/*parent*/bus_get_dma_tag(dev), /*alignment*/2,
                /*boundary*/0,
                /*lowaddr*/BUS_SPACE_MAXADDR_32BIT,
                /*highaddr*/BUS_SPACE_MAXADDR,
                /*filter*/NULL, /*filterarg*/NULL,
                /*maxsize*/via->bufsz, /*nsegments*/1, /*maxsegz*/0x3ffff,
                /*flags*/0, /*lockfunc*/NULL,
                /*lockarg*/NULL, &via->parent_dmat) != 0) {
                device_printf(dev, "unable to create dma tag\n");
                goto bad;
        }

        /*
         *  DMA tag for SGD table.  The 686 uses scatter/gather DMA and
         *  requires a list in memory of work to do.  We need only 16 bytes
         *  for this list, and it is wasteful to allocate 16K.
         */
        if (bus_dma_tag_create(/*parent*/bus_get_dma_tag(dev), /*alignment*/2,
                /*boundary*/0,
                /*lowaddr*/BUS_SPACE_MAXADDR_32BIT,
                /*highaddr*/BUS_SPACE_MAXADDR,
                /*filter*/NULL, /*filterarg*/NULL,
                /*maxsize*/nsegs * sizeof(struct via_dma_op),
                /*nsegments*/1, /*maxsegz*/0x3ffff,
                /*flags*/0, /*lockfunc*/NULL,
                /*lockarg*/NULL, &via->sgd_dmat) != 0) {
                device_printf(dev, "unable to create dma tag\n");
                goto bad;
        }

        if (bus_dmamem_alloc(via->sgd_dmat, (void **)&via->sgd_table,
            BUS_DMA_NOWAIT, &via->sgd_dmamap) == -1)
                goto bad;
        if (bus_dmamap_load(via->sgd_dmat, via->sgd_dmamap, via->sgd_table,
            nsegs * sizeof(struct via_dma_op), dma_cb, via, 0))
                goto bad;

        if (via_chip_init(dev))
                goto bad;

        via->codec = AC97_CREATE(dev, via, via_ac97);
        if (!via->codec)
                goto bad;

        mixer_init(dev, ac97_getmixerclass(), via->codec);

        via->codec_caps = ac97_getextcaps(via->codec);

        /* Try to set VRA without generating an error, VRM not reqrd yet */
        if (via->codec_caps &
            (AC97_EXTCAP_VRA | AC97_EXTCAP_VRM | AC97_EXTCAP_DRA)) {
                uint16_t ext = ac97_getextmode(via->codec);
                ext |= (via->codec_caps &
                    (AC97_EXTCAP_VRA | AC97_EXTCAP_VRM));
                ext &= ~AC97_EXTCAP_DRA;
                ac97_setextmode(via->codec, ext);
        }

        snprintf(status, SND_STATUSLEN, "port 0x%jx irq %jd on %s",
            rman_get_start(via->reg), rman_get_start(via->irq),
            device_get_nameunit(device_get_parent(dev)));

        /* Register */
        pcm_init(dev, via);
        for (i = 0; i < via_dxs_chnum; i++)
              pcm_addchan(dev, PCMDIR_PLAY, &via8233dxs_class, via);
        for (i = 0; i < via_sgd_chnum; i++)
              pcm_addchan(dev, PCMDIR_PLAY, &via8233msgd_class, via);
        for (i = 0; i < NWRCHANS; i++)
              pcm_addchan(dev, PCMDIR_REC, &via8233wr_class, via);
        if (via_dxs_chnum > 0)
                via_init_sysctls(dev);
        device_printf(dev, "<VIA DXS %sabled: DXS%s %d / SGD %d / REC %d>\n",
            (via_dxs_chnum > 0) ? "En" : "Dis", (via->dxs_src) ? "(SRC)" : "",
            via_dxs_chnum, via_sgd_chnum, NWRCHANS);

        if (pcm_register(dev, status))
              goto bad;

        return (0);
bad:
        if (via->codec)
                ac97_destroy(via->codec);
        if (via->reg)
                bus_release_resource(dev, SYS_RES_IOPORT, via->regid, via->reg);
        if (via->ih)
                bus_teardown_intr(dev, via->irq, via->ih);
        if (via->irq)
                bus_release_resource(dev, SYS_RES_IRQ, via->irqid, via->irq);
        if (via->parent_dmat)
                bus_dma_tag_destroy(via->parent_dmat);
        if (via->sgd_addr)
                bus_dmamap_unload(via->sgd_dmat, via->sgd_dmamap);
        if (via->sgd_table)
                bus_dmamem_free(via->sgd_dmat, via->sgd_table, via->sgd_dmamap);
        if (via->sgd_dmat)
                bus_dma_tag_destroy(via->sgd_dmat);
        mtx_destroy(&via->lock);
        free(via, M_DEVBUF);
        return (ENXIO);
}

static int
via_detach(device_t dev)
{
        int r;
        struct via_info *via;

        r = pcm_unregister(dev);
        if (r)
                return (r);

        via = pcm_getdevinfo(dev);

        if (via != NULL && (via->play_num != 0 || via->rec_num != 0)) {
                mtx_lock(&via->lock);
                via->polling = 0;
                callout_stop(&via->poll_timer);
                mtx_unlock(&via->lock);
                callout_drain(&via->poll_timer);
        }

        bus_release_resource(dev, SYS_RES_IOPORT, via->regid, via->reg);
        bus_teardown_intr(dev, via->irq, via->ih);
        bus_release_resource(dev, SYS_RES_IRQ, via->irqid, via->irq);
        bus_dma_tag_destroy(via->parent_dmat);
        bus_dmamap_unload(via->sgd_dmat, via->sgd_dmamap);
        bus_dmamem_free(via->sgd_dmat, via->sgd_table, via->sgd_dmamap);
        bus_dma_tag_destroy(via->sgd_dmat);
        mtx_destroy(&via->lock);
        free(via, M_DEVBUF);
        return (0);
}

static device_method_t via_methods[] = {
        DEVMETHOD(device_probe,         via_probe),
        DEVMETHOD(device_attach,        via_attach),
        DEVMETHOD(device_detach,        via_detach),
        { 0, 0}
};

static driver_t via_driver = {
        "pcm",
        via_methods,
        PCM_SOFTC_SIZE,
};

DRIVER_MODULE(snd_via8233, pci, via_driver, 0, 0);
MODULE_DEPEND(snd_via8233, sound, SOUND_MINVER, SOUND_PREFVER, SOUND_MAXVER);
MODULE_VERSION(snd_via8233, 1);