new driver: via 82c686 chipset audio

not personally tested, but i'm assured it works

Submitted by:	David Jones <dej@ox.org>
PR:		kern/20161

2 files changed, 762 insertions, 0 deletions

diff --git a/sys/dev/sound/pci/via82c686.c b/sys/dev/sound/pci/via82c686.c
new file mode 100644
index 0000000..98ca7bf
--- /dev/null
+++ b/sys/dev/sound/pci/via82c686.c
@@ -0,0 +1,654 @@
+/*
+ * 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.
+ *
+ * $FreeBSD$
+ */
+
+#include <dev/sound/pcm/sound.h>
+#include <dev/sound/pcm/ac97.h>
+
+#include <pci/pcireg.h>
+#include <pci/pcivar.h>
+#include <sys/sysctl.h>
+
+#include <dev/sound/pci/via82c686.h>
+
+#define VIA_PCI_ID 0x30581106
+#define	NSEGS		16	/* Number of segments in SGD table */
+
+#define SEGS_PER_CHAN	(NSEGS/2)
+
+#undef DEB
+#define DEB(x)
+
+struct via_info;
+
+struct via_chinfo {
+	struct via_info *parent;
+	pcm_channel *channel;
+	snd_dbuf *buffer;
+	int dir;
+};
+
+struct via_info {
+	bus_space_tag_t st;
+	bus_space_handle_t sh;
+	bus_dma_tag_t	parent_dmat;
+	bus_dma_tag_t	sgd_dmat;
+
+	struct via_chinfo pch, rch;
+	struct via_dma_op *sgd_table;
+	u_int16_t	codec_caps;
+};
+
+static u_int32_t via_rd(struct via_info *via, int regno, int size);
+static void via_wr(struct via_info *, int regno, u_int32_t data, int size);
+
+int via_waitready_codec(struct via_info *via);
+int via_waitvalid_codec(struct via_info *via);
+u_int32_t via_read_codec(void *addr, int reg);
+void via_write_codec(void *addr, int reg, u_int32_t val);
+
+static void via_intr(void *);
+bus_dmamap_callback_t dma_cb;
+
+
+/* channel interface */
+static void *viachan_init(void *devinfo, snd_dbuf *b, pcm_channel *c, int dir);
+static int viachan_setdir(void *data, int dir);
+static int viachan_setformat(void *data, u_int32_t format);
+static int viachan_setspeed(void *data, u_int32_t speed);
+static int viachan_setblocksize(void *data, u_int32_t blocksize);
+static int viachan_trigger(void *data, int go);
+static int viachan_getptr(void *data);
+static pcmchan_caps *viachan_getcaps(void *data);
+
+static pcmchan_caps via_playcaps = {
+	4000, 48000,
+	AFMT_STEREO | AFMT_U8 | AFMT_S16_LE,
+	AFMT_STEREO | AFMT_S16_LE
+};
+
+static pcmchan_caps via_reccaps = {
+	4000, 48000,
+	AFMT_STEREO | AFMT_U8 | AFMT_S16_LE,
+	AFMT_STEREO | AFMT_S16_LE
+};
+
+static pcm_channel via_chantemplate = {
+	viachan_init,
+	viachan_setdir,
+	viachan_setformat,
+	viachan_setspeed,
+	viachan_setblocksize,
+	viachan_trigger,
+	viachan_getptr,
+	viachan_getcaps,
+};
+
+
+/*
+ *  Probe and attach the card
+ */
+static int
+via_probe(device_t dev)
+{
+	if (pci_get_devid(dev) == VIA_PCI_ID) {
+	    device_set_desc(dev, "VIA VT82C686A AC'97 Audio");
+	    return 0;
+	}
+	return ENXIO;
+}
+
+
+void dma_cb(void *p, bus_dma_segment_t *bds, int a, int b)
+{
+}
+
+
+static int
+via_attach(device_t dev)
+{
+	snddev_info	*d;
+	struct via_info *via = 0;
+	struct ac97_info *codec;
+	char		status[SND_STATUSLEN];
+
+	u_int32_t	data;
+	struct resource *reg = 0;
+	int		regid;
+	struct resource *irq = 0;
+	void		*ih = 0;
+	int		irqid;
+
+	u_int16_t	v;
+	bus_dmamap_t	sgd_dma_map;
+
+	d = device_get_softc(dev);
+	if ((via = malloc(sizeof *via, M_DEVBUF, M_NOWAIT)) == NULL) {
+		device_printf(dev, "cannot allocate softc\n");
+		return ENXIO;
+	}
+	bzero(via, sizeof *via);
+
+	/* Get resources */
+	data = pci_read_config(dev, PCIR_COMMAND, 2);
+	data |= (PCIM_CMD_PORTEN | PCIM_CMD_BUSMASTEREN);
+	pci_write_config(dev, PCIR_COMMAND, data, 2);
+	data = pci_read_config(dev, PCIR_COMMAND, 2);
+
+	pci_write_config(dev, VIA_PCICONF_MISC,
+		VIA_PCICONF_ACLINKENAB | VIA_PCICONF_ACSGD |
+		VIA_PCICONF_ACNOTRST | VIA_PCICONF_ACVSR, 1);
+
+	regid = PCIR_MAPS;
+	reg = bus_alloc_resource(dev, SYS_RES_IOPORT, &regid,
+		0, ~0, 1, RF_ACTIVE);
+	if (!reg) {
+		device_printf(dev, "via: Cannot allocate bus resource.");
+		goto bad;
+	}
+	via->st = rman_get_bustag(reg);
+	via->sh = rman_get_bushandle(reg);
+
+	irqid = 0;
+	irq = bus_alloc_resource(dev, SYS_RES_IRQ, &irqid,
+		0, ~0, 1, RF_ACTIVE | RF_SHAREABLE);
+	if (!irq
+	    || bus_setup_intr(dev, irq, INTR_TYPE_TTY, via_intr, via, &ih)){
+		device_printf(dev, "unable to map interrupt\n");
+		goto bad;
+	}
+
+	via_wr(via, VIA_PLAY_MODE,
+		VIA_RPMODE_AUTOSTART |
+		VIA_RPMODE_INTR_FLAG | VIA_RPMODE_INTR_EOL, 1);
+	via_wr(via, VIA_RECORD_MODE,
+		VIA_RPMODE_AUTOSTART |
+		VIA_RPMODE_INTR_FLAG | VIA_RPMODE_INTR_EOL, 1);
+
+	codec = ac97_create(dev, via, NULL,
+		via_read_codec, via_write_codec);
+	if (!codec) goto bad;
+
+	mixer_init(d, &ac97_mixer, codec);
+
+	/*
+	 *  The mixer init resets the codec.  So enabling VRA must be done
+	 *  afterwards.
+	 */
+	v = via_read_codec(via, AC97_REG_EXT_AUDIO_ID);
+	v &= (AC97_ENAB_VRA | AC97_ENAB_MICVRA);
+	via_write_codec(via, AC97_REG_EXT_AUDIO_STAT, v);
+	via->codec_caps = v;
+	{
+	v = via_read_codec(via, AC97_REG_EXT_AUDIO_STAT);
+	DEB(printf("init: codec stat: %d\n", v));
+	}
+
+	if (!(v & AC97_CODEC_DOES_VRA)) {
+		/* no VRA => can do only 48 kbps */
+		via_playcaps.minspeed = 48000;
+		via_reccaps.minspeed = 48000;
+	}
+
+	/* DMA tag for buffers */
+	if (bus_dma_tag_create(/*parent*/NULL, /*alignment*/2, /*boundary*/0,
+		/*lowaddr*/BUS_SPACE_MAXADDR_32BIT,
+		/*highaddr*/BUS_SPACE_MAXADDR,
+		/*filter*/NULL, /*filterarg*/NULL,
+		/*maxsize*/VIA_BUFFSIZE, /*nsegments*/1, /*maxsegz*/0x3ffff,
+		/*flags*/0, &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*/NULL, /*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, &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, &sgd_dma_map) == -1) goto bad;
+	if (bus_dmamap_load(via->sgd_dmat, sgd_dma_map, via->sgd_table,
+		NSEGS * sizeof(struct via_dma_op), dma_cb, 0, 0)) goto bad;
+
+	snprintf(status, SND_STATUSLEN, "at io 0x%lx irq %ld",
+		rman_get_start(reg), rman_get_start(irq));
+
+	/* Register */
+	if (pcm_register(dev, via, 1, 1)) goto bad;
+	pcm_addchan(dev, PCMDIR_PLAY, &via_chantemplate, via);
+	pcm_addchan(dev, PCMDIR_REC, &via_chantemplate, via);
+	pcm_setstatus(dev, status);
+	return 0;
+bad:
+	if (via) free(via, M_DEVBUF);
+	bus_release_resource(dev, SYS_RES_IOPORT, regid, reg);
+	if (ih) bus_teardown_intr(dev, irq, ih);
+	if (irq) bus_release_resource(dev, SYS_RES_IRQ, irqid, irq);
+	return ENXIO;
+}
+
+
+static device_method_t via_methods[] = {
+	DEVMETHOD(device_probe,		via_probe),
+	DEVMETHOD(device_attach,	via_attach),
+	{ 0, 0}
+};
+
+static driver_t via_driver = {
+	"pcm",
+	via_methods,
+	sizeof(snddev_info),
+};
+
+static devclass_t pcm_devclass;
+
+DRIVER_MODULE(via, pci, via_driver, pcm_devclass, 0, 0);
+MODULE_DEPEND(via, snd_pcm, PCM_MINVER, PCM_PREFVER, PCM_MAXVER);
+MODULE_VERSION(via, 1);
+
+
+static u_int32_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 void
+via_wr(struct via_info *via, int regno, u_int32_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 */
+int
+via_waitready_codec(struct via_info *via)
+{
+	int i;
+
+	/* poll until codec not busy */
+	for (i = 0; (i < TIMEOUT) &&
+	    (via_rd(via, VIA_CODEC_CTL, 4) & VIA_CODEC_BUSY); i++)
+		DELAY(1);
+	if (i >= TIMEOUT) {
+		printf("via: codec busy\n");
+		return 1;
+	}
+
+	return 0;
+}
+
+
+int
+via_waitvalid_codec(struct via_info *via)
+{
+	int i;
+
+	/* poll until codec valid */
+	for (i = 0; (i < TIMEOUT) &&
+	    !(via_rd(via, VIA_CODEC_CTL, 4) & VIA_CODEC_PRIVALID); i++)
+		    DELAY(1);
+	if (i >= TIMEOUT) {
+		printf("via: codec invalid\n");
+		return 1;
+	}
+
+	return 0;
+}
+
+
+void
+via_write_codec(void *addr, int reg, u_int32_t val)
+{
+	struct via_info *via = addr;
+
+	if (via_waitready_codec(via)) return;
+
+	via_wr(via, VIA_CODEC_CTL,
+		VIA_CODEC_PRIVALID | VIA_CODEC_INDEX(reg) | val, 4);
+}
+
+
+u_int32_t
+via_read_codec(void *addr, int reg)
+{
+	struct via_info *via = addr;
+
+	if (via_waitready_codec(via))
+		return 1;
+
+	via_wr(via, VIA_CODEC_CTL,
+	    VIA_CODEC_PRIVALID | VIA_CODEC_READ | VIA_CODEC_INDEX(reg),4);
+
+	if (via_waitready_codec(via))
+		return 1;
+
+	if (via_waitvalid_codec(via))
+		return 1;
+
+	return via_rd(via, VIA_CODEC_CTL, 2);
+}
+
+
+/* channel interface */
+static void *
+viachan_init(void *devinfo, snd_dbuf *b, pcm_channel *c, int dir)
+{
+	struct via_info *via = devinfo;
+	struct via_chinfo *ch = (dir == PCMDIR_PLAY) ? &via->pch : &via->rch;
+
+	ch->parent = via;
+	ch->channel = c;
+	ch->buffer = b;
+	b->bufsize = VIA_BUFFSIZE;
+
+	if (chn_allocbuf(ch->buffer, via->parent_dmat) == -1) return NULL;
+	return ch;
+}
+
+static int
+viachan_setdir(void *data, int dir)
+{
+	struct via_chinfo *ch = data;
+	struct via_info *via = ch->parent;
+	struct via_dma_op *ado;
+	int i, chunk_size;
+	int	phys_addr, flag;
+
+	ch->dir = dir;
+	/*
+	 *  Build the scatter/gather DMA (SGD) table.
+	 *  There are four slots in the table: two for play, two for record.
+	 *  This creates two half-buffers, one of which is playing; the other
+	 *  is feeding.
+	 */
+	ado = via->sgd_table;
+	chunk_size = ch->buffer->bufsize / SEGS_PER_CHAN;
+
+	if (dir == PCMDIR_REC) {
+		ado += SEGS_PER_CHAN;
+	}
+
+DEB(printf("SGD table located at va %p\n", ado));
+	phys_addr = vtophys(ch->buffer->buf);
+	for (i = 0; i < SEGS_PER_CHAN; i++) {
+		ado->ptr = phys_addr;
+		flag = (i == SEGS_PER_CHAN-1) ?
+			VIA_DMAOP_EOL : VIA_DMAOP_FLAG;
+		ado->flags = flag | chunk_size;
+DEB(printf("ado->ptr/flags = %x/%x\n", phys_addr, flag));
+		phys_addr += chunk_size;
+		ado++;
+	}
+	return 0;
+}
+
+static int
+viachan_setformat(void *data, u_int32_t format)
+{
+	struct via_chinfo *ch = data;
+	struct via_info *via = ch->parent;
+	int	mode, mode_set;
+
+	mode_set = 0;
+	if (format & AFMT_STEREO)
+		mode_set |= VIA_RPMODE_STEREO;
+	if (format & AFMT_S16_LE)
+		mode_set |= VIA_RPMODE_16BIT;
+
+	/* Set up for output format */
+	if (ch->dir == PCMDIR_PLAY) {
+DEB(printf("set play format: %x\n", format));
+		mode = via_rd(via, VIA_PLAY_MODE, 1);
+		mode &= ~(VIA_RPMODE_16BIT | VIA_RPMODE_STEREO);
+		mode |= mode_set;
+		via_wr(via, VIA_PLAY_MODE, mode, 1);
+	}
+	else {
+DEB(printf("set record format: %x\n", format));
+		mode = via_rd(via, VIA_RECORD_MODE, 1);
+		mode &= ~(VIA_RPMODE_16BIT | VIA_RPMODE_STEREO);
+		mode |= mode_set;
+		via_wr(via, VIA_RECORD_MODE, mode, 1);
+	}
+
+	return 0;
+}
+
+static int
+viachan_setspeed(void *data, u_int32_t speed)
+{
+	struct via_chinfo *ch = data;
+	struct via_info *via = ch->parent;
+
+	/*
+	 *  Basic AC'97 defines a 48 kHz sample rate only.  For other rates,
+	 *  upsampling is required.
+	 *
+	 *  The VT82C686A does not perform upsampling, and neither do we.
+	 *  If the codec supports variable-rate audio (i.e. does the upsampling
+	 *  itself), then negotiate the rate with the codec.  Otherwise,
+	 *  return 48 kHz cuz that's all you got.
+	 */
+	if (ch->dir == PCMDIR_PLAY) {
+DEB(printf("requested play speed: %d\n", speed));
+		if (via->codec_caps & AC97_CODEC_DOES_VRA) {
+			via_write_codec(via, AC97_REG_EXT_DAC_RATE, speed);
+			speed = via_read_codec(via, AC97_REG_EXT_DAC_RATE);
+		}
+		else {
+DEB(printf("VRA not supported!\n"));
+			speed = 48000;
+		}
+DEB(printf("obtained play speed: %d\n", speed));
+	}
+	else {
+DEB(printf("requested record speed: %d\n", speed));
+		if (via->codec_caps & AC97_CODEC_DOES_VRA) {
+			via_write_codec(via, AC97_REG_EXT_ADC_RATE, speed);
+			speed = via_read_codec(via, AC97_REG_EXT_ADC_RATE);
+		}
+		else {
+DEB(printf("VRA not supported!\n"));
+			speed = 48000;
+		}
+DEB(printf("obtained record speed: %d\n", speed));
+	}
+	return speed;
+}
+
+static int
+viachan_setblocksize(void *data, u_int32_t blocksize)
+{
+	struct via_chinfo *ch = data;
+
+	return ch->buffer->bufsize / 2;
+}
+
+static int
+viachan_trigger(void *data, int go)
+{
+	struct via_chinfo *ch = data;
+	struct via_info *via = ch->parent;
+	struct via_dma_op *ado;
+
+	if (go == PCMTRIG_EMLDMAWR || go == PCMTRIG_EMLDMARD) return 0;
+	if (ch->dir == PCMDIR_PLAY) {
+		if (go == PCMTRIG_START) {
+			ado = &via->sgd_table[0];
+DEB(printf("ado located at va=%p pa=%x\n", ado, vtophys(ado)));
+			via_wr(via, VIA_PLAY_DMAOPS_BASE, vtophys(ado),4);
+			via_wr(via, VIA_PLAY_CONTROL,
+				VIA_RPCTRL_START, 1);
+		}
+		else {
+			/* Stop DMA */
+			via_wr(via, VIA_PLAY_CONTROL,
+				VIA_RPCTRL_TERMINATE, 1);
+		}
+	} else {
+		if (go == PCMTRIG_START) {
+			ado = &via->sgd_table[SEGS_PER_CHAN];
+DEB(printf("ado located at va=%p pa=%x\n", ado, vtophys(ado)));
+			via_wr(via, VIA_RECORD_DMAOPS_BASE,
+				vtophys(ado),4);
+			via_wr(via, VIA_RECORD_CONTROL,
+				VIA_RPCTRL_START, 1);
+		}
+		else {
+			/* Stop DMA */
+			via_wr(via, VIA_RECORD_CONTROL,
+				VIA_RPCTRL_TERMINATE, 1);
+		}
+	}
+
+DEB(printf("viachan_trigger: go=%d\n", go));
+	return 0;
+}
+
+static int
+viachan_getptr(void *data)
+{
+	struct via_chinfo *ch = data;
+	struct via_info *via = ch->parent;
+	struct via_dma_op *ado;
+	int	ptr, base, len, seg;
+	int base1;
+
+	if (ch->dir == PCMDIR_PLAY) {
+		ado = &via->sgd_table[0];
+		base1 = via_rd(via, VIA_PLAY_DMAOPS_BASE, 4);
+		len = via_rd(via, VIA_PLAY_DMAOPS_COUNT, 4);
+		base = via_rd(via, VIA_PLAY_DMAOPS_BASE, 4);
+		if (base != base1) {	/* Avoid race hazzard	*/
+			len = via_rd(via, VIA_PLAY_DMAOPS_COUNT, 4);
+		}
+DEB(printf("viachan_getptr: len / base = %x / %x\n", len, base));
+
+		/* Base points to SGD segment to do, one past current */
+
+		/* Determine how many segments have been done */
+		seg = (base - vtophys(ado)) / sizeof(struct via_dma_op);
+		if (seg == 0) seg = SEGS_PER_CHAN;
+
+		/* Now work out offset: seg less count */
+		ptr = seg * ch->buffer->bufsize / SEGS_PER_CHAN - len;
+DEB(printf("return ptr=%d\n", ptr));
+		return ptr;
+	}
+	else {
+		base1 = via_rd(via, VIA_RECORD_DMAOPS_BASE, 4);
+		ado = &via->sgd_table[SEGS_PER_CHAN];
+		len = via_rd(via, VIA_RECORD_DMAOPS_COUNT, 4);
+		base = via_rd(via, VIA_RECORD_DMAOPS_BASE, 4);
+		if (base != base1) {	/* Avoid race hazzard	*/
+			len = via_rd(via, VIA_RECORD_DMAOPS_COUNT, 4);
+		}
+DEB(printf("viachan_getptr: len / base = %x / %x\n", len, base));
+
+		/* Base points to next block to do, one past current */
+
+		/* Determine how many segments have been done */
+		seg = (base - vtophys(ado)) / sizeof(struct via_dma_op);
+		if (seg == 0) seg = SEGS_PER_CHAN;
+
+		/* Now work out offset: seg less count */
+		ptr = seg * ch->buffer->bufsize / SEGS_PER_CHAN - len;
+
+		/* DMA appears to operate on memory 'lines' of 32 bytes	*/
+		/* so don't return any part line - it isn't in RAM yet	*/
+		ptr = ptr & ~0x1f;
+DEB(printf("return ptr=%d\n", ptr));
+		return ptr;
+	}
+	return 0;
+}
+
+static pcmchan_caps *
+viachan_getcaps(void *data)
+{
+	struct via_chinfo *ch = data;
+	return (ch->dir == PCMDIR_PLAY) ? &via_playcaps : &via_reccaps;
+}
+
+static void
+via_intr(void *p)
+{
+	struct via_info *via = p;
+	int		st;
+
+DEB(printf("viachan_intr\n"));
+	/* Read channel */
+	st = via_rd(via, VIA_PLAY_STAT, 1);
+	if (st & VIA_RPSTAT_INTR) {
+		via_wr(via, VIA_PLAY_STAT, VIA_RPSTAT_INTR, 1);
+		chn_intr(via->pch.channel);
+	}
+
+	/* Write channel */
+	st = via_rd(via, VIA_RECORD_STAT, 1);
+	if (st & VIA_RPSTAT_INTR) {
+		via_wr(via, VIA_RECORD_STAT, VIA_RPSTAT_INTR, 1);
+		chn_intr(via->rch.channel);
+	}
+}
+
+
diff --git a/sys/dev/sound/pci/via82c686.h b/sys/dev/sound/pci/via82c686.h
new file mode 100644
index 0000000..1d85c9b
--- /dev/null
+++ b/sys/dev/sound/pci/via82c686.h
@@ -0,0 +1,108 @@
+/*-
+ * Copyright (c) 2000 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Tyler C. Sarna.
+ *
+ * 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.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *      This product includes software developed by the NetBSD
+ *      Foundation, Inc. and its contributors.
+ * 4. Neither the name of The NetBSD Foundation nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * 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.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _VIA_H
+#define _VIA_H
+
+/*
+ * VIA Technologies VT82C686A Southbridge Audio Driver
+ *
+ * Documentation links:
+ *
+ * ftp://ftp.alsa-project.org/pub/manuals/via/686a.pdf
+ * ftp://ftp.alsa-project.org/pub/manuals/general/ac97r21.pdf
+ * ftp://ftp.alsa-project.org/pub/manuals/ad/AD1881_0.pdf (example AC'97 codec)
+ */
+
+struct via_dma_op {
+        u_int32_t ptr;
+        u_int32_t flags;
+#define VIA_DMAOP_EOL         0x80000000
+#define VIA_DMAOP_FLAG        0x40000000
+#define VIA_DMAOP_STOP        0x20000000
+#define VIA_DMAOP_COUNT(x)    ((x)&0x00FFFFFF)
+};
+
+#define VIA_PCICONF_MISC      0x41
+#define         VIA_PCICONF_ACLINKENAB 0x80     /* ac link enab */
+#define         VIA_PCICONF_ACNOTRST   0x40     /* ~(ac reset) */
+#define         VIA_PCICONF_ACSYNC     0x20     /* ac sync */
+#define         VIA_PCICONF_ACVSR      0x08     /* var. samp. rate */
+#define         VIA_PCICONF_ACSGD      0x04     /* SGD enab */
+#define         VIA_PCICONF_ACFM       0x02     /* FM enab */
+#define         VIA_PCICONF_ACSB       0x01     /* SB enab */
+#define VIA_PCICONF_FUNC_EN	0x42
+
+#define VIA_PLAY_STAT                 0x00
+#define VIA_RECORD_STAT               0x10
+#define         VIA_RPSTAT_INTR               0x03
+#define VIA_PLAY_CONTROL              0x01
+#define VIA_RECORD_CONTROL            0x11
+#define         VIA_RPCTRL_START              0x80
+#define         VIA_RPCTRL_TERMINATE          0x40
+#define VIA_PLAY_MODE                 0x02
+#define VIA_RECORD_MODE               0x12
+#define         VIA_RPMODE_INTR_FLAG          0x01
+#define         VIA_RPMODE_INTR_EOL           0x02
+#define         VIA_RPMODE_STEREO             0x10
+#define         VIA_RPMODE_16BIT              0x20
+#define         VIA_RPMODE_AUTOSTART          0x80
+#define VIA_PLAY_DMAOPS_BASE          0x04
+#define VIA_RECORD_DMAOPS_BASE        0x14
+#define VIA_PLAY_DMAOPS_COUNT         0x0C
+#define VIA_RECORD_DMAOPS_COUNT       0x1C
+
+#define VIA_CODEC_CTL                 0x80
+#define         VIA_CODEC_READ                0x00800000
+#define         VIA_CODEC_BUSY                0x01000000
+#define         VIA_CODEC_PRIVALID            0x02000000
+#define         VIA_CODEC_INDEX(x)            ((x)<<16)
+
+#define AC97_REG_EXT_AUDIO_ID           0x28
+#define         AC97_CODEC_DOES_VRA             0x0001
+#define         AC97_CODEC_DOES_MICVRA          0x0008
+#define AC97_REG_EXT_AUDIO_STAT         0x2A
+#define         AC97_ENAB_VRA                   0x0001
+#define         AC97_ENAB_MICVRA                0x0008
+#define AC97_REG_EXT_DAC_RATE           0x2C
+#define AC97_REG_EXT_ADC_RATE           0x32
+
+#define TIMEOUT	50
+#define	VIA_BUFFSIZE	0x4000
+
+#endif /* _VIA_H */