AC-97 CODEC support. Some help from FreeBSD, esp. on nice printing of

features.

2 files changed, 776 insertions, 0 deletions

diff --git a/sys/dev/ic/ac97.c b/sys/dev/ic/ac97.c
new file mode 100644
index 00000000000..77762814f33
--- /dev/null
+++ b/sys/dev/ic/ac97.c
@@ -0,0 +1,718 @@
+/*      $OpenBSD: ac97.c,v 1.1 1999/09/19 06:45:12 csapuntz Exp $ */
+
+/*
+ * Copyright (c) 1999 Constantine Sapuntzakis
+ *
+ * Author:        Constantine Sapuntzakis <csapuntz@stanford.edu>
+ *
+ * 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 CONSTANTINE SAPUNTZAKIS 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.
+ */
+
+/* Partially inspired by FreeBSD's sys/dev/pcm/ac97.c. It came with
+   the following copyright */
+
+/*
+ * Copyright (c) 1999 Cameron Grant <gandalf@vilnya.demon.co.uk>
+ * 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 <sys/param.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/malloc.h>
+#include <sys/device.h>
+
+#include <sys/audioio.h>
+#include <dev/audio_if.h>
+#include <dev/ic/ac97.h>
+
+#define AC97_REG_RESET                0x00
+#define AC97_SOUND_ENHANCEMENT(reg)   (((reg) >> 10) & 0x1f)
+#define AC97_REG_MASTER_VOLUME        0x02
+#define AC97_REG_HEADPHONE_VOLUME     0x04
+#define AC97_REG_MASTER_VOLUME_MONO   0x06
+#define AC97_REG_MASTER_TONE          0x08
+#define AC97_REG_PCBEEP_VOLUME        0x0a
+#define AC97_REG_PHONE_VOLUME         0x0c
+#define AC97_REG_MIC_VOLUME           0x0e
+#define AC97_REG_LINEIN_VOLUME        0x10
+#define AC97_REG_CD_VOLUME            0x12
+#define AC97_REG_VIDEO_VOLUME         0x14
+#define AC97_REG_AUX_VOLUME           0x16
+#define AC97_REG_PCMOUT_VOLUME        0x18
+#define AC97_REG_RECORD_SELECT        0x1a
+#define AC97_REG_RECORD_GAIN          0x1c
+#define AC97_REG_RECORD_GAIN_MIC      0x1e
+#define AC97_REG_GP                   0x20
+#define AC97_REG_3D_CONTROL           0x22
+#define AC97_REG_POWER                0x26
+#define AC97_REG_VENDOR_ID1           0x7c
+#define AC97_REG_VENDOR_ID2           0x7e
+
+static struct audio_mixer_enum ac97_on_off = { 2,
+					       { { { AudioNoff } , 0 },
+					         { { AudioNon }  , 1 } }};
+
+
+static struct audio_mixer_enum ac97_mic_select = { 2,
+					       { { { AudioNmicrophone "0" }, 
+						   0 },
+					         { { AudioNmicrophone "1" }, 
+						   1 } }};
+
+static struct audio_mixer_enum ac97_mono_select = { 2,
+					       { { { AudioNmixerout },
+						   0 },
+					         { { AudioNmicrophone }, 
+						   1 } }};
+
+static struct audio_mixer_enum ac97_source = { 8,
+					       { { { AudioNmicrophone } , 0 },
+						 { { AudioNcd }, 1 },
+						 { { "video" }, 2 },
+						 { { AudioNaux }, 3 },
+						 { { AudioNline }, 4 },
+						 { { AudioNmixerout }, 5 },
+						 { { AudioNmixerout AudioNmono }, 6 },
+						 { { "phone" }, 7 }}};
+
+static struct audio_mixer_value ac97_volume_stereo = { { AudioNvolume }, 
+						       2 };
+
+
+static struct audio_mixer_value ac97_volume_mono = { { AudioNvolume }, 
+						     1 };
+
+#define WRAP(a)  &a, sizeof(a)
+
+struct ac97_source_info {
+	char *class;
+	char *device;
+	char *qualifier;
+	int  type;
+
+	void *info;
+	int  info_size;
+
+	u_int8_t  reg;
+	u_int8_t  bits:3;
+	u_int8_t  ofs:4;
+	u_int8_t  mute:1;
+	u_int8_t  polarity:1;   /* Does 0 == MAX or MIN */
+
+	int  prev;
+	int  next;	
+	int  mixer_class;
+} source_info[] = {
+	{ AudioCinputs ,            NULL,           NULL,    AUDIO_MIXER_CLASS,
+	},
+	{ AudioCoutputs,            NULL,           NULL,    AUDIO_MIXER_CLASS,
+	},
+	{ AudioCrecord ,            NULL,           NULL,    AUDIO_MIXER_CLASS,
+	},
+	/* Stereo master volume*/
+	{ AudioCoutputs,     AudioNmaster,        NULL,    AUDIO_MIXER_VALUE,
+	  WRAP(ac97_volume_stereo), 
+	  AC97_REG_MASTER_VOLUME, 5, 0, 1,
+	},
+	/* Mono volume */
+	{ AudioCoutputs,       AudioNmono,        NULL,    AUDIO_MIXER_VALUE,
+	  WRAP(ac97_volume_mono),
+	  AC97_REG_MASTER_VOLUME_MONO, 6, 0, 1,
+	},
+	{ AudioCoutputs,       AudioNmono,AudioNsource,   AUDIO_MIXER_ENUM,
+	  WRAP(ac97_mono_select),
+	  AC97_REG_GP, 1, 9, 0,
+	},
+	/* Headphone volume */
+	{ AudioCoutputs,  AudioNheadphone,        NULL,    AUDIO_MIXER_VALUE,
+	  WRAP(ac97_volume_stereo),
+	  AC97_REG_HEADPHONE_VOLUME, 6, 0, 1,
+	},
+	/* Tone */
+	{ AudioCoutputs,           "tone",        NULL,    AUDIO_MIXER_VALUE,
+	  WRAP(ac97_volume_stereo),
+	  AC97_REG_MASTER_TONE, 4, 0, 0,
+	},
+	/* PC Beep Volume */
+	{ AudioCinputs,     AudioNspeaker,        NULL,    AUDIO_MIXER_VALUE,
+	  WRAP(ac97_volume_mono), 
+	  AC97_REG_PCBEEP_VOLUME, 4, 1, 1,
+	},
+	/* Phone */
+	{ AudioCinputs,           "phone",        NULL,    AUDIO_MIXER_VALUE,
+	  WRAP(ac97_volume_mono), 
+	  AC97_REG_PHONE_VOLUME, 5, 0, 1,
+	},
+	/* Mic Volume */
+	{ AudioCinputs,  AudioNmicrophone,        NULL,    AUDIO_MIXER_VALUE,
+	  WRAP(ac97_volume_mono), 
+	  AC97_REG_MIC_VOLUME, 5, 0, 1,
+	},
+	{ AudioCinputs,  AudioNmicrophone, AudioNpreamp,   AUDIO_MIXER_ENUM,
+	  WRAP(ac97_on_off),
+	  AC97_REG_MIC_VOLUME, 1, 6, 0,
+	},
+	{ AudioCinputs,  AudioNmicrophone, AudioNsource,   AUDIO_MIXER_ENUM,
+	  WRAP(ac97_mic_select),
+	  AC97_REG_GP, 1, 8, 0,
+	},
+	/* Line in Volume */
+	{ AudioCinputs,        AudioNline,        NULL,    AUDIO_MIXER_VALUE,
+	  WRAP(ac97_volume_stereo),
+	  AC97_REG_LINEIN_VOLUME, 5, 0, 1,
+	},
+	/* CD Volume */
+	{ AudioCinputs,          AudioNcd,        NULL,    AUDIO_MIXER_VALUE,
+	  WRAP(ac97_volume_stereo),
+	  AC97_REG_CD_VOLUME, 5, 0, 1,
+	},
+	/* Video Volume */
+	{ AudioCinputs,           "video",        NULL,    AUDIO_MIXER_VALUE,
+	  WRAP(ac97_volume_stereo),
+	  AC97_REG_VIDEO_VOLUME, 5, 0, 1,
+	},
+	/* AUX volume */
+	{ AudioCinputs,         AudioNaux,        NULL,    AUDIO_MIXER_VALUE,
+	  WRAP(ac97_volume_stereo),
+	  AC97_REG_AUX_VOLUME, 5, 0, 1,
+	},
+	/* PCM out volume */
+	{ AudioCinputs,         AudioNdac,        NULL,    AUDIO_MIXER_VALUE,
+	  WRAP(ac97_volume_stereo),
+	  AC97_REG_PCMOUT_VOLUME, 5, 0, 1,
+	},
+	/* Record Source - some logic for this is hard coded - see below */
+	{ AudioCrecord,      AudioNsource,        NULL,    AUDIO_MIXER_ENUM,
+	  WRAP(ac97_source),
+	  AC97_REG_RECORD_SELECT, 3, 0, 0,
+	},
+	/* Record Gain */
+	{ AudioCrecord,      AudioNvolume,        NULL,    AUDIO_MIXER_VALUE,
+	  WRAP(ac97_volume_stereo),
+	  AC97_REG_RECORD_GAIN, 4, 0, 1,
+	},
+	/* Record Gain mic */
+	{ AudioCrecord,  AudioNmicrophone,        NULL,    AUDIO_MIXER_VALUE,
+	  WRAP(ac97_volume_mono), 
+	  AC97_REG_RECORD_GAIN_MIC, 4, 0, 1, 1,
+	},
+	/* */
+	{ AudioCoutputs,   AudioNloudness,        NULL,    AUDIO_MIXER_ENUM,
+	  WRAP(ac97_on_off),
+	  AC97_REG_GP, 1, 12, 0,
+	},
+	{ AudioCoutputs,    AudioNspatial,        NULL,    AUDIO_MIXER_ENUM,
+	  WRAP(ac97_on_off),
+	  AC97_REG_GP, 1, 13, 0,
+	},
+	{ AudioCoutputs,    AudioNspatial,    "center",    AUDIO_MIXER_VALUE,
+	  WRAP(ac97_volume_mono), 
+	  AC97_REG_3D_CONTROL, 4, 8, 0, 1,
+	},
+	{ AudioCoutputs,    AudioNspatial,     "depth",    AUDIO_MIXER_VALUE,
+	  WRAP(ac97_volume_mono), 
+	  AC97_REG_3D_CONTROL, 4, 0, 0, 1,
+	},
+
+	/* Missing features: Simulated Stereo, POP, Loopback mode */
+} ;
+
+#define SOURCE_INFO_SIZE (sizeof(source_info)/sizeof(source_info[0]))
+
+/*
+ * Check out http://developer.intel.com/pc-supp/platform/ac97/ for
+ * information on AC-97
+ */
+
+struct ac97_softc {
+	struct ac97_codec_if codecIf;
+
+	struct ac97_host_if *hostIf;
+
+	struct ac97_source_info source_info[2 * SOURCE_INFO_SIZE];
+	int num_source_info;
+};
+
+int ac97_mixer_get_port __P((struct ac97_codec_if *self, mixer_ctrl_t *cp));
+int ac97_mixer_set_port __P((struct ac97_codec_if *self, mixer_ctrl_t *));
+int ac97_query_devinfo __P((struct ac97_codec_if *self, mixer_devinfo_t *));
+
+struct ac97_codec_if_vtbl ac97civ = {
+	ac97_mixer_get_port, 
+	ac97_mixer_set_port,
+	ac97_query_devinfo
+};
+
+static struct ac97_codecid {
+	u_int32_t id;
+	char *name;
+} ac97codecid[] = {
+	{ 0x414B4D00, "Asahi Kasei AK4540" 	},
+	{ 0x43525900, "Cirrus Logic CS4297" 	},
+	{ 0x83847600, "SigmaTel STAC????" 	},
+	{ 0x83847604, "SigmaTel STAC9701/3/4/5" },
+	{ 0x83847605, "SigmaTel STAC9704" 	},
+	{ 0x83847608, "SigmaTel STAC9708" 	},
+	{ 0x83847609, "SigmaTel STAC9721" 	},
+	{ 0, 	      NULL			}
+};
+
+static char *ac97enhancement[] = {
+	"No 3D Stereo",
+	"Analog Devices Phat Stereo",
+	"Creative"
+	"National Semi 3D",
+	"Yamaha Ymersion",
+	"BBE 3D",
+	"Crystal Semi 3D"
+	"Qsound QXpander",
+	"Spatializer 3D",
+	"SRS 3D",
+	"Platform Tech 3D",
+	"AKM 3D",
+	"Aureal",
+	"AZTECH 3D",
+	"Binaura 3D",
+	"ESS Technology",
+	"Harman International VMAx",
+	"Nvidea 3D",
+	"Philips Incredible Sound",
+	"Texas Instruments' 3D",
+	"VLSI Technology 3D",
+	"TriTech 3D",
+	"Realtek 3D",
+	"Samsung 3D",
+	"Wolfson Microelectronics 3D",
+	"Delta Integration 3D",
+	"SigmaTel 3D",
+	"Unknown 3D",
+	"Rockwell 3D",
+	"Unknown 3D",
+	"Unknown 3D",
+	"Unknown 3D",
+};
+
+static char *ac97feature[] = {
+	"mic channel",
+	"reserved",
+	"tone",
+	"simulated stereo",
+	"headphone",
+	"bass boost",
+	"18 bit DAC",
+	"20 bit DAC",
+	"18 bit ADC",
+	"20 bit ADC"
+};
+
+
+int ac97_str_equal __P((char *, char *));
+void ac97_setup_source_info __P((struct ac97_softc *));
+
+#define AUDIO_DEBUG
+#define AC97_DEBUG 0
+
+#ifdef AUDIO_DEBUG
+#define DPRINTF(x)	if (ac97debug) printf x
+#define DPRINTFN(n,x)	if (ac97debug>(n)) printf x
+#ifdef AC97_DEBUG
+int	ac97debug = AC97_DEBUG;
+#else
+int	ac97debug = 0;
+#endif
+#else
+#define DPRINTF(x)
+#define DPRINTFN(n,x)
+#endif
+
+
+int
+ac97_str_equal(a, b)
+	char *a, *b;
+{
+	return ((a == b) || (a && b && (!strcmp(a, b))));
+}
+
+void
+ac97_setup_source_info(as)
+	struct ac97_softc *as;
+{
+	int idx, ouridx;
+	struct ac97_source_info *si, *si2; 
+
+	for (idx = 0, ouridx = 0; idx < SOURCE_INFO_SIZE; idx++) {
+		si = &as->source_info[ouridx];
+
+		bcopy(&source_info[idx], si, sizeof(*si));
+
+		switch (si->type) {
+		case AUDIO_MIXER_CLASS:
+		        si->mixer_class = ouridx;
+			ouridx++;
+			break;
+		case AUDIO_MIXER_VALUE:
+			/* Todo - Test to see if it works */
+			ouridx++;
+
+			/* Add an entry for mute, if necessary */
+			if (si->mute) {
+				si = &as->source_info[ouridx];
+				bcopy(&source_info[idx], si, sizeof(*si));
+				si->qualifier = AudioNmute;
+				si->type = AUDIO_MIXER_ENUM;
+				si->info = &ac97_on_off;
+				si->info_size = sizeof(ac97_on_off);
+				si->bits = 1;
+				si->ofs = 15;
+				si->mute = 0;
+				si->polarity = 0;
+				ouridx++;
+			}
+			break;
+		case AUDIO_MIXER_ENUM:
+			/* Todo - Test to see if it works */
+			ouridx++;
+			break;
+		default:
+			printf ("ac97: shouldn't get here\n");
+			break;
+		}
+	}
+
+	as->num_source_info = ouridx;
+
+	for (idx = 0; idx < as->num_source_info; idx++) {
+		int idx2, previdx;
+
+		si = &as->source_info[idx];
+
+		/* Find mixer class */
+		for (idx2 = 0; idx2 < as->num_source_info; idx2++) {
+			si2 = &as->source_info[idx2];
+
+			if (si2->type == AUDIO_MIXER_CLASS && 
+			    ac97_str_equal(si->class,
+					   si2->class)) {
+				si->mixer_class = idx2;
+			}
+		}
+
+
+		/* Setup prev and next pointers */
+		if (si->prev != 0)
+			continue;
+
+		if (si->qualifier)
+			continue;
+
+		si->prev = AUDIO_MIXER_LAST;
+		previdx = idx;
+
+		for (idx2 = 0; idx2 < as->num_source_info; idx2++) {
+			if (idx2 == idx)
+				continue;
+
+			si2 = &as->source_info[idx2];
+
+			if (!si2->prev &&
+			    ac97_str_equal(si->class, si2->class) &&
+			    ac97_str_equal(si->device, si2->device)) {
+				as->source_info[previdx].next = idx2;
+				as->source_info[idx2].prev = previdx;
+				
+				previdx = idx2;
+			}
+		}
+
+		as->source_info[previdx].next = AUDIO_MIXER_LAST;
+	}
+}
+
+int 
+ac97_attach(hostIf)
+	struct ac97_host_if *hostIf;
+{
+	struct ac97_softc *as;
+	int error, i, j;
+	u_int16_t id1, id2, caps;
+	u_int32_t id;
+	
+	as = malloc(sizeof(struct ac97_softc), M_DEVBUF, M_WAITOK);
+
+	if (!as) return (ENOMEM);
+
+	as->codecIf.vtbl = &ac97civ;
+	as->hostIf = hostIf;
+
+	if ((error = hostIf->attach(hostIf->arg, &as->codecIf))) {
+		free (as, M_DEVBUF);
+		return (error);
+	}
+
+	hostIf->reset(hostIf->arg);
+	DELAY(1000);
+
+	hostIf->write(hostIf->arg, AC97_REG_POWER, 0);
+	hostIf->write(hostIf->arg, AC97_REG_RESET, 0);
+	DELAY(10000);
+
+	if ((error = hostIf->read(hostIf->arg, AC97_REG_VENDOR_ID1, &id1)))
+		return (error);
+
+	if ((error = hostIf->read(hostIf->arg, AC97_REG_VENDOR_ID2, &id2)))
+		return (error);
+
+	if ((error = hostIf->read(hostIf->arg, AC97_REG_RESET, &caps)))
+		return (error);
+
+	id = (id1 << 16) | id2;
+
+	printf("ac97: codec id 0x%8x", id);
+	for (i = 0; ac97codecid[i].id; i++) {
+		if (ac97codecid[i].id == id) 
+			printf(" (%s)", ac97codecid[i].name);
+	}
+	printf("\nac97: codec features ");
+	for (i = j = 0; i < 10; i++) {
+		if (caps & (1 << i)) {
+			printf("%s%s", j? ", " : "", ac97feature[i]);
+			j++;
+		}
+	}
+
+	printf("%s%s\n", j? ", " : "", ac97enhancement[(caps >> 10) & 0x1f]);
+
+	ac97_setup_source_info(as);
+
+	return (0);
+}
+
+
+int 
+ac97_query_devinfo(codec_if, dip)
+	struct ac97_codec_if *codec_if;
+	mixer_devinfo_t *dip;
+{
+	struct ac97_softc *as = (struct ac97_softc *)codec_if;
+
+	if (dip->index < as->num_source_info) {
+		struct ac97_source_info *si = &as->source_info[dip->index];
+		char *name;
+
+		dip->type = si->type;
+		dip->mixer_class = si->mixer_class;
+		dip->prev = si->prev;
+		dip->next = si->next;
+		
+		if (si->qualifier)
+			name = si->qualifier;
+		else if (si->device)
+			name = si->device;
+		else if (si->class)
+			name = si->class;
+		
+		if (name)
+			strcpy(dip->label.name, name);
+
+		bcopy(si->info, &dip->un, si->info_size);
+		return (0);
+	}
+
+	return (ENXIO);
+}
+
+
+
+int
+ac97_mixer_set_port(codec_if, cp)
+	struct ac97_codec_if *codec_if;
+	mixer_ctrl_t *cp;
+{
+	struct ac97_softc *as = (struct ac97_softc *)codec_if;
+	struct ac97_source_info *si = &as->source_info[cp->dev];
+	u_int16_t mask;
+	u_int16_t val, newval;
+	int error;
+
+	if (cp->dev < 0 || cp->dev >= as->num_source_info)
+		return (EINVAL);
+
+	if (cp->type != si->type)
+		return (EINVAL);
+
+	error = as->hostIf->read(as->hostIf->arg, si->reg, &val);
+	if (error)
+		return (error);
+
+	DPRINTFN(5, ("read(%x) = %x\n", si->reg, val));
+
+	mask = (1 << si->bits) - 1;
+
+	switch (cp->type) {
+	case AUDIO_MIXER_ENUM:
+		if (cp->un.ord > mask || cp->un.ord < 0)
+			return (EINVAL);
+
+		newval = (cp->un.ord << si->ofs);
+		if (si->reg == AC97_REG_RECORD_SELECT) {
+			newval |= (newval << (8 + si->ofs));
+			mask |= (mask << 8);
+		}
+		break;
+	case AUDIO_MIXER_VALUE:
+	{
+		struct audio_mixer_value *value = si->info;
+		u_int16_t  l, r;
+
+		if (cp->un.value.num_channels != 
+		    value->num_channels) return (EINVAL);
+
+		if (cp->un.value.num_channels == 1) {
+			l = r = cp->un.value.level[AUDIO_MIXER_LEVEL_MONO];
+		} else {
+			l = cp->un.value.level[AUDIO_MIXER_LEVEL_LEFT];
+			r = cp->un.value.level[AUDIO_MIXER_LEVEL_RIGHT];
+		}
+
+		if (!si->polarity) {
+			l = 255 - l;
+			r = 255 - r;
+		}
+		
+		l = l >> (8 - si->bits);
+		r = r >> (8 - si->bits);
+
+		newval = ((l & mask) << si->ofs);
+		if (value->num_channels == 2) {
+			newval |= ((r & mask) << (si->ofs + 8));
+			mask |= (mask << 8);
+		}
+
+		break;
+	}
+	default:
+		return (EINVAL);
+	}
+
+	mask = mask << si->ofs;
+	error = as->hostIf->write(as->hostIf->arg, si->reg, (val & ~mask) | newval);
+	if (error)
+		return (error);
+
+	return (0);
+}
+
+int
+ac97_mixer_get_port(codec_if, cp)
+	struct ac97_codec_if *codec_if;
+	mixer_ctrl_t *cp;
+{
+	struct ac97_softc *as = (struct ac97_softc *)codec_if;
+	struct ac97_source_info *si = &as->source_info[cp->dev];
+	u_int16_t mask;
+	u_int16_t val;
+	int error;
+
+	if (cp->dev < 0 || cp->dev >= as->num_source_info)
+		return (EINVAL);
+
+	if (cp->type != si->type)
+		return (EINVAL);
+
+	error = as->hostIf->read(as->hostIf->arg, si->reg, &val);
+	if (error)
+		return (error);
+
+	DPRINTFN(5, ("read(%x) = %x\n", si->reg, val));
+
+	mask = (1 << si->bits) - 1;
+
+	switch (cp->type) {
+	case AUDIO_MIXER_ENUM:
+		cp->un.ord = (val >> si->ofs) & mask;
+		DPRINTFN(4, ("AUDIO_MIXER_ENUM: %x %d %x %d\n", val, si->ofs, mask, cp->un.ord));
+		break;
+	case AUDIO_MIXER_VALUE:
+	{
+		struct audio_mixer_value *value = si->info;
+		u_int16_t  l, r;
+
+		if (cp->un.value.num_channels != 
+		    value->num_channels) return (EINVAL);
+
+		if (value->num_channels == 1) {
+			l = r = (val >> si->ofs) & mask;
+		} else {
+			l = (val >> si->ofs) & mask;
+			r = (val >> (si->ofs + 8)) & mask;
+		}
+
+		l = (l << (8 - si->bits));
+		r = (r << (8 - si->bits));
+		if (!si->polarity) {
+			l = 255 - l;
+			r = 255 - r;
+		}
+
+		/* The EAP driver averages l and r for stereo
+		   channels that are requested in MONO mode. Does this
+		   make sense? */
+		if (cp->un.value.num_channels == 1) {
+			cp->un.value.level[AUDIO_MIXER_LEVEL_MONO] = l;
+		} else if (cp->un.value.num_channels == 2) {
+			cp->un.value.level[AUDIO_MIXER_LEVEL_LEFT] = l;
+			cp->un.value.level[AUDIO_MIXER_LEVEL_RIGHT] = r;
+		}
+
+		break;
+	}
+	default:
+		return (EINVAL);
+	}
+
+	return (0);
+}
+
diff --git a/sys/dev/ic/ac97.h b/sys/dev/ic/ac97.h
new file mode 100644
index 00000000000..018bbe73184
--- /dev/null
+++ b/sys/dev/ic/ac97.h
@@ -0,0 +1,58 @@
+/*      $OpenBSD: ac97.h,v 1.1 1999/09/19 06:45:12 csapuntz Exp $ */
+
+/*
+ * Copyright (c) 1999 Constantine Sapuntzakis
+ *
+ * Author:        Constantine Sapuntzakis <csapuntz@stanford.edu>
+ *
+ * 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 CONSTANTINE SAPUNTZAKIS 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.
+ */
+
+struct ac97_codec_if;
+
+/* 
+ * This is the interface used to attach the AC97 compliant CODEC.
+ */
+struct ac97_host_if {
+	void  *arg;
+
+	int (*attach)(void *arg, struct ac97_codec_if *codecif);
+	int (*read)(void *arg, u_int8_t reg, u_int16_t *val);
+	int (*write)(void *arg, u_int8_t reg, u_int16_t val);
+	void (*reset)(void *arg);
+};
+
+/*
+ * This is the interface exported by the AC97 compliant CODEC
+ */
+
+struct ac97_codec_if_vtbl {
+	int (*mixer_get_port)(struct ac97_codec_if *addr, mixer_ctrl_t *cp);
+	int (*mixer_set_port)(struct ac97_codec_if *addr, mixer_ctrl_t *cp);
+	int (*query_devinfo)(struct ac97_codec_if *addr, mixer_devinfo_t *cp);
+};
+
+struct ac97_codec_if {
+	struct ac97_codec_if_vtbl *vtbl;
+};
+
+int ac97_attach __P((struct ac97_host_if *));