xref: /src/sys/dev/pci/cs4281.c

/*	$NetBSD: cs4281.c,v 1.59.2.1 2025/08/02 05:56:45 perseant Exp $	*/

/*
 * Copyright (c) 2000 Tatoku Ogaito.  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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by Tatoku Ogaito
 *	for the NetBSD Project.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
 */

/*
 * Cirrus Logic CS4281 driver.
 * Data sheets can be found
 * http://www.cirrus.com/ftp/pub/4281.pdf
 * ftp://ftp.alsa-project.org/pub/manuals/cirrus/cs4281tm.pdf
 *
 * TODO:
 *   1: midi and FM support
 *   2: ...
 *
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: cs4281.c,v 1.59.2.1 2025/08/02 05:56:45 perseant Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/fcntl.h>
#include <sys/device.h>
#include <sys/systm.h>

#include <dev/pci/pcidevs.h>
#include <dev/pci/pcivar.h>
#include <dev/pci/cs4281reg.h>
#include <dev/pci/cs428xreg.h>

#include <sys/audioio.h>
#include <dev/audio/audio_if.h>
#include <dev/midi_if.h>

#include <dev/ic/ac97reg.h>
#include <dev/ic/ac97var.h>

#include <dev/pci/cs428x.h>

#include <sys/bus.h>

#if defined(ENABLE_SECONDARY_CODEC)
#define MAX_CHANNELS  (4)
#define MAX_FIFO_SIZE 32 /* 128/4channels */
#else
#define MAX_CHANNELS  (2)
#define MAX_FIFO_SIZE 64 /* 128/2channels */
#endif

/* IF functions for audio driver */
static int	cs4281_match(device_t, cfdata_t, void *);
static void	cs4281_attach(device_t, device_t, void *);
static int	cs4281_intr(void *);
static int	cs4281_query_format(void *, audio_format_query_t *);
static int	cs4281_set_format(void *, int,
				 const audio_params_t *, const audio_params_t *,
				 audio_filter_reg_t *, audio_filter_reg_t *);
static int	cs4281_halt_output(void *);
static int	cs4281_halt_input(void *);
static int	cs4281_getdev(void *, struct audio_device *);
static int	cs4281_trigger_output(void *, void *, void *, int,
				      void (*)(void *), void *,
				      const audio_params_t *);
static int	cs4281_trigger_input(void *, void *, void *, int,
				     void (*)(void *), void *,
				     const audio_params_t *);

static int	cs4281_reset_codec(void *);

/* Internal functions */
static uint8_t	cs4281_sr2regval(int);
static void	cs4281_set_dac_rate(struct cs428x_softc *, int);
static void	cs4281_set_adc_rate(struct cs428x_softc *, int);
static int      cs4281_init(struct cs428x_softc *, int);

/* Power Management */
static bool	cs4281_suspend(device_t, const pmf_qual_t *);
static bool	cs4281_resume(device_t, const pmf_qual_t *);

static const struct audio_hw_if cs4281_hw_if = {
	.query_format		= cs4281_query_format,
	.set_format		= cs4281_set_format,
	.round_blocksize	= cs428x_round_blocksize,
	.halt_output		= cs4281_halt_output,
	.halt_input		= cs4281_halt_input,
	.getdev			= cs4281_getdev,
	.set_port		= cs428x_mixer_set_port,
	.get_port		= cs428x_mixer_get_port,
	.query_devinfo		= cs428x_query_devinfo,
	.allocm			= cs428x_malloc,
	.freem			= cs428x_free,
	.round_buffersize	= cs428x_round_buffersize,
	.get_props		= cs428x_get_props,
	.trigger_output		= cs4281_trigger_output,
	.trigger_input		= cs4281_trigger_input,
	.get_locks		= cs428x_get_locks,
};

#if NMIDI > 0 && 0
/* Midi Interface */
static void	cs4281_midi_close(void*);
static void	cs4281_midi_getinfo(void *, struct midi_info *);
static int	cs4281_midi_open(void *, int, void (*)(void *, int),
			 void (*)(void *), void *);
static int	cs4281_midi_output(void *, int);

static const struct midi_hw_if cs4281_midi_hw_if = {
	cs4281_midi_open,
	cs4281_midi_close,
	cs4281_midi_output,
	cs4281_midi_getinfo,
	0,
	cs428x_get_locks,
};
#endif

CFATTACH_DECL_NEW(clct, sizeof(struct cs428x_softc),
    cs4281_match, cs4281_attach, NULL, NULL);

static struct audio_device cs4281_device = {
	"CS4281",
	"",
	"cs4281"
};

static const struct audio_format cs4281_formats[] = {
	{
		.mode		= AUMODE_PLAY | AUMODE_RECORD,
		.encoding	= AUDIO_ENCODING_SLINEAR_NE,
		.validbits	= 16,
		.precision	= 16,
		.channels	= 2,
		.channel_mask	= AUFMT_STEREO,
		.frequency_type	= 6,
		.frequency	= { 8000, 11025, 16000, 22050, 44100, 48000 },
	},
};
#define CS4281_NFORMATS __arraycount(cs4281_formats)

static int
cs4281_match(device_t parent, cfdata_t match, void *aux)
{
	struct pci_attach_args *pa;

	pa = (struct pci_attach_args *)aux;
	if (PCI_VENDOR(pa->pa_id) != PCI_VENDOR_CIRRUS)
		return 0;
	if (PCI_PRODUCT(pa->pa_id) == PCI_PRODUCT_CIRRUS_CS4281)
		return 1;
	return 0;
}

static void
cs4281_attach(device_t parent, device_t self, void *aux)
{
	struct cs428x_softc *sc;
	struct pci_attach_args *pa;
	pci_chipset_tag_t pc;
	char const *intrstr;
	pcireg_t reg;
	int error;
	char intrbuf[PCI_INTRSTR_LEN];

	sc = device_private(self);
	sc->sc_dev = self;
	pa = (struct pci_attach_args *)aux;
	pc = pa->pa_pc;

	pci_aprint_devinfo(pa, "Audio controller");

	sc->sc_pc = pa->pa_pc;
	sc->sc_pt = pa->pa_tag;

	/* Map I/O register */
	if (pci_mapreg_map(pa, PCI_BA0,
	    PCI_MAPREG_TYPE_MEM|PCI_MAPREG_MEM_TYPE_32BIT, 0,
	    &sc->ba0t, &sc->ba0h, NULL, NULL)) {
		aprint_error_dev(sc->sc_dev, "can't map BA0 space\n");
		return;
	}
	if (pci_mapreg_map(pa, PCI_BA1,
	    PCI_MAPREG_TYPE_MEM|PCI_MAPREG_MEM_TYPE_32BIT, 0,
	    &sc->ba1t, &sc->ba1h, NULL, NULL)) {
		aprint_error_dev(sc->sc_dev, "can't map BA1 space\n");
		return;
	}

	sc->sc_dmatag = pa->pa_dmat;

	/* power up chip */
	if ((error = pci_activate(pa->pa_pc, pa->pa_tag, self,
	    pci_activate_null)) && error != EOPNOTSUPP) {
		aprint_error_dev(sc->sc_dev, "cannot activate %d\n", error);
		return;
	}

	/* Enable the device (set bus master flag) */
	reg = pci_conf_read(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG);
	pci_conf_write(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG,
	    reg | PCI_COMMAND_MASTER_ENABLE);

#if 0
	/* LATENCY_TIMER setting */
	temp1 = pci_conf_read(pa->pa_pc, pa->pa_tag, PCI_BHLC_REG);
	if (PCI_LATTIMER(temp1) < 32) {
		temp1 &= 0xffff00ff;
		temp1 |= 0x00002000;
		pci_conf_write(pa->pa_pc, pa->pa_tag, PCI_BHLC_REG, temp1);
	}
#endif

	/* Map and establish the interrupt. */
	if (pci_intr_map(pa, &sc->intrh)) {
		aprint_error_dev(sc->sc_dev, "couldn't map interrupt\n");
		return;
	}
	intrstr = pci_intr_string(pc, sc->intrh, intrbuf, sizeof(intrbuf));

	mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_NONE);
	mutex_init(&sc->sc_intr_lock, MUTEX_DEFAULT, IPL_AUDIO);

	sc->sc_ih = pci_intr_establish_xname(sc->sc_pc, sc->intrh, IPL_AUDIO,
	    cs4281_intr, sc, device_xname(self));
	if (sc->sc_ih == NULL) {
		aprint_error_dev(sc->sc_dev, "couldn't establish interrupt");
		if (intrstr != NULL)
			aprint_error(" at %s", intrstr);
		aprint_error("\n");
		mutex_destroy(&sc->sc_lock);
		mutex_destroy(&sc->sc_intr_lock);
		return;
	}
	aprint_normal_dev(sc->sc_dev, "interrupting at %s\n", intrstr);

	/*
	 * Sound System start-up
	 */
	if (cs4281_init(sc, 1) != 0) {
		mutex_destroy(&sc->sc_lock);
		mutex_destroy(&sc->sc_intr_lock);
		return;
	}

	sc->type = TYPE_CS4281;

	sc->dma_size     = CS4281_BUFFER_SIZE / MAX_CHANNELS;
	sc->dma_align    = 0x10;
	sc->hw_blocksize = sc->dma_size / 2;

	/* AC 97 attachment */
	sc->host_if.arg = sc;
	sc->host_if.attach = cs428x_attach_codec;
	sc->host_if.read   = cs428x_read_codec;
	sc->host_if.write  = cs428x_write_codec;
	sc->host_if.reset  = cs4281_reset_codec;
	if (ac97_attach(&sc->host_if, self, &sc->sc_lock) != 0) {
		aprint_error_dev(sc->sc_dev, "ac97_attach failed\n");
		mutex_destroy(&sc->sc_lock);
		mutex_destroy(&sc->sc_intr_lock);
		return;
	}
	audio_attach_mi(&cs4281_hw_if, sc, sc->sc_dev);

#if NMIDI > 0 && 0
	midi_attach_mi(&cs4281_midi_hw_if, sc, sc->sc_dev);
#endif

	if (!pmf_device_register(self, cs4281_suspend, cs4281_resume))
		aprint_error_dev(self, "couldn't establish power handler\n");
}

static int
cs4281_intr(void *p)
{
	struct cs428x_softc *sc;
	uint32_t intr, hdsr0, hdsr1;
	char *empty_dma;
	int handled;

	sc = p;
	handled = 0;
	hdsr0 = 0;
	hdsr1 = 0;

	mutex_spin_enter(&sc->sc_intr_lock);

	/* grab interrupt register */
	intr = BA0READ4(sc, CS4281_HISR);

	DPRINTF(("cs4281_intr:"));
	/* not for me */
	if ((intr & HISR_INTENA) == 0) {
		/* clear the interrupt register */
		BA0WRITE4(sc, CS4281_HICR, HICR_CHGM | HICR_IEV);
		mutex_spin_exit(&sc->sc_intr_lock);
		return 0;
	}

	if (intr & HISR_DMA0)
		hdsr0 = BA0READ4(sc, CS4281_HDSR0); /* clear intr condition */
	if (intr & HISR_DMA1)
		hdsr1 = BA0READ4(sc, CS4281_HDSR1); /* clear intr condition */
	/* clear the interrupt register */
	BA0WRITE4(sc, CS4281_HICR, HICR_CHGM | HICR_IEV);

#ifdef CS4280_DEBUG
	DPRINTF(("intr = 0x%08x, hdsr0 = 0x%08x hdsr1 = 0x%08x\n",
		 intr, hdsr0, hdsr1));
#else
	__USE(hdsr0);
	__USE(hdsr1);
#endif

	/* Playback Interrupt */
	if (intr & HISR_DMA0) {
		handled = 1;
		if (sc->sc_prun) {
			DPRINTF((" PB DMA 0x%x(%d)",
				(int)BA0READ4(sc, CS4281_DCA0),
				(int)BA0READ4(sc, CS4281_DCC0)));
			if ((sc->sc_pi%sc->sc_pcount) == 0)
				sc->sc_pintr(sc->sc_parg);
			/* copy buffer */
			++sc->sc_pi;
			empty_dma = sc->sc_pdma->addr;
			if (sc->sc_pi&1)
				empty_dma += sc->hw_blocksize;
			memcpy(empty_dma, sc->sc_pn, sc->hw_blocksize);
			sc->sc_pn += sc->hw_blocksize;
			if (sc->sc_pn >= sc->sc_pe)
				sc->sc_pn = sc->sc_ps;
		} else {
			aprint_error_dev(sc->sc_dev, "unexpected play intr\n");
		}
	}
	if (intr & HISR_DMA1) {
		handled = 1;
		if (sc->sc_rrun) {
			/* copy from DMA */
			DPRINTF((" CP DMA 0x%x(%d)", (int)BA0READ4(sc, CS4281_DCA1),
				(int)BA0READ4(sc, CS4281_DCC1)));
			++sc->sc_ri;
			empty_dma = sc->sc_rdma->addr;
			if ((sc->sc_ri & 1) == 0)
				empty_dma += sc->hw_blocksize;
			memcpy(sc->sc_rn, empty_dma, sc->hw_blocksize);
			sc->sc_rn += sc->hw_blocksize;
			if (sc->sc_rn >= sc->sc_re)
				sc->sc_rn = sc->sc_rs;
			if ((sc->sc_ri % sc->sc_rcount) == 0)
				sc->sc_rintr(sc->sc_rarg);
		} else {
			aprint_error_dev(sc->sc_dev,
			    "unexpected record intr\n");
		}
	}
	DPRINTF(("\n"));

	mutex_spin_exit(&sc->sc_intr_lock);

	return handled;
}

static int
cs4281_query_format(void *addr, audio_format_query_t *afp)
{

	return audio_query_format(cs4281_formats, CS4281_NFORMATS, afp);
}

static int
cs4281_set_format(void *addr, int setmode,
    const audio_params_t *play, const audio_params_t *rec,
    audio_filter_reg_t *pfil, audio_filter_reg_t *rfil)
{
	struct cs428x_softc *sc;

	sc = addr;
	/* set sample rate */
	cs4281_set_dac_rate(sc, play->sample_rate);
	cs4281_set_adc_rate(sc, rec->sample_rate);
	return 0;
}

static int
cs4281_halt_output(void *addr)
{
	struct cs428x_softc *sc;

	sc = addr;
	BA0WRITE4(sc, CS4281_DCR0, BA0READ4(sc, CS4281_DCR0) | DCRn_MSK);
	sc->sc_prun = 0;
	return 0;
}

static int
cs4281_halt_input(void *addr)
{
	struct cs428x_softc *sc;

	sc = addr;
	BA0WRITE4(sc, CS4281_DCR1, BA0READ4(sc, CS4281_DCR1) | DCRn_MSK);
	sc->sc_rrun = 0;
	return 0;
}

static int
cs4281_getdev(void *addr, struct audio_device *retp)
{

	*retp = cs4281_device;
	return 0;
}

static int
cs4281_trigger_output(void *addr, void *start, void *end, int blksize,
		      void (*intr)(void *), void *arg,
		      const audio_params_t *param)
{
	struct cs428x_softc *sc;
	uint32_t fmt;
	struct cs428x_dma *p;
	int dma_count;

	sc = addr;
	fmt = 0;
#ifdef DIAGNOSTIC
	if (sc->sc_prun)
		printf("cs4281_trigger_output: already running\n");
#endif
	sc->sc_prun = 1;

	DPRINTF(("cs4281_trigger_output: sc=%p start=%p end=%p "
		 "blksize=%d intr=%p(%p)\n", addr, start, end, blksize, intr, arg));
	sc->sc_pintr = intr;
	sc->sc_parg  = arg;

	/* stop playback DMA */
	BA0WRITE4(sc, CS4281_DCR0, BA0READ4(sc, CS4281_DCR0) | DCRn_MSK);

	DPRINTF(("param: precision=%d channels=%d encoding=%d\n",
	       param->precision, param->channels, param->encoding));
	for (p = sc->sc_dmas; p != NULL && BUFADDR(p) != start; p = p->next)
		continue;
	if (p == NULL) {
		printf("cs4281_trigger_output: bad addr %p\n", start);
		return EINVAL;
	}

	sc->sc_pcount = blksize / sc->hw_blocksize;
	sc->sc_ps = (char *)start;
	sc->sc_pe = (char *)end;
	sc->sc_pdma = p;
	sc->sc_pbuf = KERNADDR(p);
	sc->sc_pi = 0;
	sc->sc_pn = sc->sc_ps;
	if (blksize >= sc->dma_size) {
		sc->sc_pn = sc->sc_ps + sc->dma_size;
		memcpy(sc->sc_pbuf, start, sc->dma_size);
		++sc->sc_pi;
	} else {
		sc->sc_pn = sc->sc_ps + sc->hw_blocksize;
		memcpy(sc->sc_pbuf, start, sc->hw_blocksize);
	}

	dma_count = sc->dma_size;
	if (param->precision != 8)
		dma_count /= 2;   /* 16 bit */
	if (param->channels > 1)
		dma_count /= 2;   /* Stereo */

	DPRINTF(("cs4281_trigger_output: DMAADDR(p)=0x%x count=%d\n",
		 (int)DMAADDR(p), dma_count));
	BA0WRITE4(sc, CS4281_DBA0, DMAADDR(p));
	BA0WRITE4(sc, CS4281_DBC0, dma_count-1);

	/* set playback format */
	fmt = BA0READ4(sc, CS4281_DMR0) & ~DMRn_FMTMSK;
	if (param->encoding == AUDIO_ENCODING_SLINEAR_BE)
		fmt |= DMRn_BEND;
	BA0WRITE4(sc, CS4281_DMR0, fmt);

	/* set sample rate */
	sc->sc_prate = param->sample_rate;
	cs4281_set_dac_rate(sc, param->sample_rate);

	/* start DMA */
	BA0WRITE4(sc, CS4281_DCR0, BA0READ4(sc, CS4281_DCR0) & ~DCRn_MSK);
	/* Enable interrupts */
	BA0WRITE4(sc, CS4281_HICR, HICR_IEV | HICR_CHGM);

	DPRINTF(("HICR =0x%08x(expected 0x00000001)\n", BA0READ4(sc, CS4281_HICR)));
	DPRINTF(("HIMR =0x%08x(expected 0x00f0fc3f)\n", BA0READ4(sc, CS4281_HIMR)));
	DPRINTF(("DMR0 =0x%08x(expected 0x2???0018)\n", BA0READ4(sc, CS4281_DMR0)));
	DPRINTF(("DCR0 =0x%08x(expected 0x00030000)\n", BA0READ4(sc, CS4281_DCR0)));
	DPRINTF(("FCR0 =0x%08x(expected 0x81000f00)\n", BA0READ4(sc, CS4281_FCR0)));
	DPRINTF(("DACSR=0x%08x(expected 1 for 44kHz 5 for 8kHz)\n",
		 BA0READ4(sc, CS4281_DACSR)));
	DPRINTF(("SRCSA=0x%08x(expected 0x0b0a0100)\n", BA0READ4(sc, CS4281_SRCSA)));
	DPRINTF(("SSPM&SSPM_PSRCEN =0x%08x(expected 0x00000010)\n",
		 BA0READ4(sc, CS4281_SSPM) & SSPM_PSRCEN));

	return 0;
}

static int
cs4281_trigger_input(void *addr, void *start, void *end, int blksize,
		     void (*intr)(void *), void *arg,
		     const audio_params_t *param)
{
	struct cs428x_softc *sc;
	struct cs428x_dma *p;
	uint32_t fmt;
	int dma_count;

	sc = addr;
	fmt = 0;
#ifdef DIAGNOSTIC
	if (sc->sc_rrun)
		printf("cs4281_trigger_input: already running\n");
#endif
	sc->sc_rrun = 1;
	DPRINTF(("cs4281_trigger_input: sc=%p start=%p end=%p "
	    "blksize=%d intr=%p(%p)\n", addr, start, end, blksize, intr, arg));
	sc->sc_rintr = intr;
	sc->sc_rarg  = arg;

	/* stop recording DMA */
	BA0WRITE4(sc, CS4281_DCR1, BA0READ4(sc, CS4281_DCR1) | DCRn_MSK);

	for (p = sc->sc_dmas; p && BUFADDR(p) != start; p = p->next)
		continue;
	if (!p) {
		printf("cs4281_trigger_input: bad addr %p\n", start);
		return EINVAL;
	}

	sc->sc_rcount = blksize / sc->hw_blocksize;
	sc->sc_rs = (char *)start;
	sc->sc_re = (char *)end;
	sc->sc_rdma = p;
	sc->sc_rbuf = KERNADDR(p);
	sc->sc_ri = 0;
	sc->sc_rn = sc->sc_rs;

	dma_count = sc->dma_size;
	if (param->precision != 8)
		dma_count /= 2;
	if (param->channels > 1)
		dma_count /= 2;

	DPRINTF(("cs4281_trigger_input: DMAADDR(p)=0x%x count=%d\n",
		 (int)DMAADDR(p), dma_count));
	BA0WRITE4(sc, CS4281_DBA1, DMAADDR(p));
	BA0WRITE4(sc, CS4281_DBC1, dma_count-1);

	/* set recording format */
	fmt = BA0READ4(sc, CS4281_DMR1) & ~DMRn_FMTMSK;
	if (param->encoding == AUDIO_ENCODING_SLINEAR_BE)
		fmt |= DMRn_BEND;
	BA0WRITE4(sc, CS4281_DMR1, fmt);

	/* set sample rate */
	sc->sc_rrate = param->sample_rate;
	cs4281_set_adc_rate(sc, param->sample_rate);

	/* Start DMA */
	BA0WRITE4(sc, CS4281_DCR1, BA0READ4(sc, CS4281_DCR1) & ~DCRn_MSK);
	/* Enable interrupts */
	BA0WRITE4(sc, CS4281_HICR, HICR_IEV | HICR_CHGM);

	DPRINTF(("HICR=0x%08x\n", BA0READ4(sc, CS4281_HICR)));
	DPRINTF(("HIMR=0x%08x\n", BA0READ4(sc, CS4281_HIMR)));
	DPRINTF(("DMR1=0x%08x\n", BA0READ4(sc, CS4281_DMR1)));
	DPRINTF(("DCR1=0x%08x\n", BA0READ4(sc, CS4281_DCR1)));

	return 0;
}

static bool
cs4281_suspend(device_t dv, const pmf_qual_t *qual)
{
	struct cs428x_softc *sc = device_private(dv);

	mutex_enter(&sc->sc_lock);
	mutex_spin_enter(&sc->sc_intr_lock);

	/* save current playback status */
	if (sc->sc_prun) {
		sc->sc_suspend_state.cs4281.dcr0 = BA0READ4(sc, CS4281_DCR0);
		sc->sc_suspend_state.cs4281.dmr0 = BA0READ4(sc, CS4281_DMR0);
		sc->sc_suspend_state.cs4281.dbc0 = BA0READ4(sc, CS4281_DBC0);
		sc->sc_suspend_state.cs4281.dba0 = BA0READ4(sc, CS4281_DBA0);
	}

	/* save current capture status */
	if (sc->sc_rrun) {
		sc->sc_suspend_state.cs4281.dcr1 = BA0READ4(sc, CS4281_DCR1);
		sc->sc_suspend_state.cs4281.dmr1 = BA0READ4(sc, CS4281_DMR1);
		sc->sc_suspend_state.cs4281.dbc1 = BA0READ4(sc, CS4281_DBC1);
		sc->sc_suspend_state.cs4281.dba1 = BA0READ4(sc, CS4281_DBA1);
	}
	/* Stop DMA */
	BA0WRITE4(sc, CS4281_DCR0, BA0READ4(sc, CS4281_DCR0) | DCRn_MSK);
	BA0WRITE4(sc, CS4281_DCR1, BA0READ4(sc, CS4281_DCR1) | DCRn_MSK);

	mutex_spin_exit(&sc->sc_intr_lock);
	mutex_exit(&sc->sc_lock);

	return true;
}

static bool
cs4281_resume(device_t dv, const pmf_qual_t *qual)
{
	struct cs428x_softc *sc = device_private(dv);

	mutex_enter(&sc->sc_lock);
	mutex_spin_enter(&sc->sc_intr_lock);

	cs4281_init(sc, 0);
	cs4281_reset_codec(sc);

	/* restore ac97 registers */
	mutex_spin_exit(&sc->sc_intr_lock);
	(*sc->codec_if->vtbl->restore_ports)(sc->codec_if);
	mutex_spin_enter(&sc->sc_intr_lock);

	/* restore DMA related status */
	if (sc->sc_prun) {
		cs4281_set_dac_rate(sc, sc->sc_prate);
		BA0WRITE4(sc, CS4281_DBA0, sc->sc_suspend_state.cs4281.dba0);
		BA0WRITE4(sc, CS4281_DBC0, sc->sc_suspend_state.cs4281.dbc0);
		BA0WRITE4(sc, CS4281_DMR0, sc->sc_suspend_state.cs4281.dmr0);
		BA0WRITE4(sc, CS4281_DCR0, sc->sc_suspend_state.cs4281.dcr0);
	}
	if (sc->sc_rrun) {
		cs4281_set_adc_rate(sc, sc->sc_rrate);
		BA0WRITE4(sc, CS4281_DBA1, sc->sc_suspend_state.cs4281.dba1);
		BA0WRITE4(sc, CS4281_DBC1, sc->sc_suspend_state.cs4281.dbc1);
		BA0WRITE4(sc, CS4281_DMR1, sc->sc_suspend_state.cs4281.dmr1);
		BA0WRITE4(sc, CS4281_DCR1, sc->sc_suspend_state.cs4281.dcr1);
	}
	/* enable interrupts */
	if (sc->sc_prun || sc->sc_rrun)
		BA0WRITE4(sc, CS4281_HICR, HICR_IEV | HICR_CHGM);

	mutex_spin_exit(&sc->sc_intr_lock);
	mutex_exit(&sc->sc_lock);

	return true;
}

/* control AC97 codec */
static int
cs4281_reset_codec(void *addr)
{
	struct cs428x_softc *sc;
	uint16_t data;
	uint32_t dat32;
	int n;

	sc = addr;

	DPRINTFN(3, ("cs4281_reset_codec\n"));

	/* Reset codec */
	BA0WRITE4(sc, CS428X_ACCTL, 0);
	delay(50);    /* delay 50us */

	BA0WRITE4(sc, CS4281_SPMC, 0);
	delay(100);	/* delay 100us */
	BA0WRITE4(sc, CS4281_SPMC, SPMC_RSTN);
#if defined(ENABLE_SECONDARY_CODEC)
	BA0WRITE4(sc, CS4281_SPMC, SPMC_RSTN | SPCM_ASDIN2E);
	BA0WRITE4(sc, CS4281_SERMC, SERMC_TCID);
#endif
	delay(50000);   /* XXX: delay 50ms */

	/* Enable ASYNC generation */
	BA0WRITE4(sc, CS428X_ACCTL, ACCTL_ESYN);

	/* Wait for codec ready. Linux driver waits 50ms here */
	n = 0;
	while ((BA0READ4(sc, CS428X_ACSTS) & ACSTS_CRDY) == 0) {
		delay(100);
		if (++n > 1000) {
			printf("reset_codec: AC97 codec ready timeout\n");
			return ETIMEDOUT;
		}
	}
#if defined(ENABLE_SECONDARY_CODEC)
	/* secondary codec ready*/
	n = 0;
	while ((BA0READ4(sc, CS4281_ACSTS2) & ACSTS2_CRDY2) == 0) {
		delay(100);
		if (++n > 1000)
			return 0;
	}
#endif
	/* Set the serial timing configuration */
	/* XXX: undocumented but the Linux driver do this */
	BA0WRITE4(sc, CS4281_SERMC, SERMC_PTCAC97);

	/* Wait for codec ready signal */
	n = 0;
	do {
		delay(1000);
		if (++n > 1000) {
			aprint_error_dev(sc->sc_dev,
			    "timeout waiting for codec ready\n");
			return ETIMEDOUT;
		}
		dat32 = BA0READ4(sc, CS428X_ACSTS) & ACSTS_CRDY;
	} while (dat32 == 0);

	/* Enable Valid Frame output on ASDOUT */
	BA0WRITE4(sc, CS428X_ACCTL, ACCTL_ESYN | ACCTL_VFRM);

	/* Wait until codec calibration is finished. Codec register 26h */
	n = 0;
	do {
		delay(1);
		if (++n > 1000) {
			aprint_error_dev(sc->sc_dev,
			    "timeout waiting for codec calibration\n");
			return ETIMEDOUT;
		}
		cs428x_read_codec(sc, AC97_REG_POWER, &data);
	} while ((data & 0x0f) != 0x0f);

	/* Set the serial timing configuration again */
	/* XXX: undocumented but the Linux driver do this */
	BA0WRITE4(sc, CS4281_SERMC, SERMC_PTCAC97);

	/* Wait until we've sampled input slots 3 & 4 as valid */
	n = 0;
	do {
		delay(1000);
		if (++n > 1000) {
			aprint_error_dev(sc->sc_dev, "timeout waiting for "
			    "sampled input slots as valid\n");
			return ETIMEDOUT;
		}
		dat32 = BA0READ4(sc, CS428X_ACISV) & (ACISV_ISV3 | ACISV_ISV4) ;
	} while (dat32 != (ACISV_ISV3 | ACISV_ISV4));

	/* Start digital data transfer of audio data to the codec */
	BA0WRITE4(sc, CS428X_ACOSV, (ACOSV_SLV3 | ACOSV_SLV4));
	return 0;
}


/* Internal functions */

/* convert sample rate to register value */
static uint8_t
cs4281_sr2regval(int rate)
{
	uint8_t retval;

	/* We don't have to change here. but anyway ... */
	if (rate > 48000)
		rate = 48000;
	if (rate < 6023)
		rate = 6023;

	switch (rate) {
	case 8000:
		retval = 5;
		break;
	case 11025:
		retval = 4;
		break;
	case 16000:
		retval = 3;
		break;
	case 22050:
		retval = 2;
		break;
	case 44100:
		retval = 1;
		break;
	case 48000:
		retval = 0;
		break;
	default:
		retval = 1536000/rate; /* == 24576000/(rate*16) */
	}
	return retval;
}

static void
cs4281_set_adc_rate(struct cs428x_softc *sc, int rate)
{

	BA0WRITE4(sc, CS4281_ADCSR, cs4281_sr2regval(rate));
}

static void
cs4281_set_dac_rate(struct cs428x_softc *sc, int rate)
{

	BA0WRITE4(sc, CS4281_DACSR, cs4281_sr2regval(rate));
}

static int
cs4281_init(struct cs428x_softc *sc, int init)
{
	int n;
	uint16_t data;
	uint32_t dat32;

	/* set "Configuration Write Protect" register to
	 * 0x4281 to allow to write */
	BA0WRITE4(sc, CS4281_CWPR, 0x4281);

	/*
	 * Unset "Full Power-Down bit of Extended PCI Power Management
	 * Control" register to release the reset state.
	 */
	dat32 = BA0READ4(sc, CS4281_EPPMC);
	if (dat32 & EPPMC_FPDN) {
		BA0WRITE4(sc, CS4281_EPPMC, dat32 & ~EPPMC_FPDN);
	}

	/* Start PLL out in known state */
	BA0WRITE4(sc, CS4281_CLKCR1, 0);
	/* Start serial ports out in known state */
	BA0WRITE4(sc, CS4281_SERMC, 0);

	/* Reset codec */
	BA0WRITE4(sc, CS428X_ACCTL, 0);
	delay(50);	/* delay 50us */

	BA0WRITE4(sc, CS4281_SPMC, 0);
	delay(100);	/* delay 100us */
	BA0WRITE4(sc, CS4281_SPMC, SPMC_RSTN);
#if defined(ENABLE_SECONDARY_CODEC)
	BA0WRITE4(sc, CS4281_SPMC, SPMC_RSTN | SPCM_ASDIN2E);
	BA0WRITE4(sc, CS4281_SERMC, SERMC_TCID);
#endif
	delay(50000);   /* XXX: delay 50ms */

	/* Turn on Sound System clocks based on ABITCLK */
	BA0WRITE4(sc, CS4281_CLKCR1, CLKCR1_DLLP);
	delay(50000);   /* XXX: delay 50ms */
	BA0WRITE4(sc, CS4281_CLKCR1, CLKCR1_SWCE | CLKCR1_DLLP);

	/* Set enables for sections that are needed in the SSPM registers */
	BA0WRITE4(sc, CS4281_SSPM,
		  SSPM_MIXEN |		/* Mixer */
		  SSPM_CSRCEN |		/* Capture SRC */
		  SSPM_PSRCEN |		/* Playback SRC */
		  SSPM_JSEN |		/* Joystick */
		  SSPM_ACLEN |		/* AC LINK */
		  SSPM_FMEN		/* FM */
		  );

	/* Wait for clock stabilization */
	n = 0;
#if 1
	/* what document says */
	while ((BA0READ4(sc, CS4281_CLKCR1) & (CLKCR1_DLLRDY | CLKCR1_CLKON))
		 != (CLKCR1_DLLRDY | CLKCR1_CLKON)) {
		delay(100);
		if (++n > 1000) {
			aprint_error_dev(sc->sc_dev,
			    "timeout waiting for clock stabilization\n");
			return -1;
		}
	}
#else
	/* Cirrus driver for Linux does */
	while (!(BA0READ4(sc, CS4281_CLKCR1) & CLKCR1_DLLRDY)) {
		delay(1000);
		if (++n > 1000) {
			aprint_error_dev(sc->sc_dev,
			    "timeout waiting for clock stabilization\n");
			return -1;
		}
	}
#endif

	/* Enable ASYNC generation */
	BA0WRITE4(sc, CS428X_ACCTL, ACCTL_ESYN);

	/* Wait for codec ready. Linux driver waits 50ms here */
	n = 0;
	while ((BA0READ4(sc, CS428X_ACSTS) & ACSTS_CRDY) == 0) {
		delay(100);
		if (++n > 1000) {
			aprint_error_dev(sc->sc_dev,
			    "timeout waiting for codec ready\n");
			return -1;
		}
	}

#if defined(ENABLE_SECONDARY_CODEC)
	/* secondary codec ready*/
	n = 0;
	while ((BA0READ4(sc, CS4281_ACSTS2) & ACSTS2_CRDY2) == 0) {
		delay(100);
		if (++n > 1000) {
			aprint_error_dev(sc->sc_dev,
			    "timeout waiting for secondary codec ready\n");
			return -1;
		}
	}
#endif

	/* Set the serial timing configuration */
	/* XXX: undocumented but the Linux driver do this */
	BA0WRITE4(sc, CS4281_SERMC, SERMC_PTCAC97);

	/* Wait for codec ready signal */
	n = 0;
	do {
		delay(1000);
		if (++n > 1000) {
			aprint_error_dev(sc->sc_dev,
			    "timeout waiting for codec ready\n");
			return -1;
		}
		dat32 = BA0READ4(sc, CS428X_ACSTS) & ACSTS_CRDY;
	} while (dat32 == 0);

	/* Enable Valid Frame output on ASDOUT */
	BA0WRITE4(sc, CS428X_ACCTL, ACCTL_ESYN | ACCTL_VFRM);

	/* Wait until codec calibration is finished. codec register 26h */
	n = 0;
	do {
		delay(1);
		if (++n > 1000) {
			aprint_error_dev(sc->sc_dev,
			    "timeout waiting for codec calibration\n");
			return -1;
		}
		cs428x_read_codec(sc, AC97_REG_POWER, &data);
	} while ((data & 0x0f) != 0x0f);

	/* Set the serial timing configuration again */
	/* XXX: undocumented but the Linux driver do this */
	BA0WRITE4(sc, CS4281_SERMC, SERMC_PTCAC97);

	/* Wait until we've sampled input slots 3 & 4 as valid */
	n = 0;
	do {
		delay(1000);
		if (++n > 1000) {
			aprint_error_dev(sc->sc_dev, "timeout waiting for "
			    "sampled input slots as valid\n");
			return -1;
		}
		dat32 = BA0READ4(sc, CS428X_ACISV) & (ACISV_ISV3 | ACISV_ISV4);
	} while (dat32 != (ACISV_ISV3 | ACISV_ISV4));

	/* Start digital data transfer of audio data to the codec */
	BA0WRITE4(sc, CS428X_ACOSV, (ACOSV_SLV3 | ACOSV_SLV4));

	cs428x_write_codec(sc, AC97_REG_HEADPHONE_VOLUME, 0);
	cs428x_write_codec(sc, AC97_REG_MASTER_VOLUME, 0);

	/* Power on the DAC */
	cs428x_read_codec(sc, AC97_REG_POWER, &data);
	cs428x_write_codec(sc, AC97_REG_POWER, data & 0xfdff);

	/* Wait until we sample a DAC ready state.
	 * Not documented, but Linux driver does.
	 */
	for (n = 0; n < 32; ++n) {
		delay(1000);
		cs428x_read_codec(sc, AC97_REG_POWER, &data);
		if (data & 0x02)
			break;
	}

	/* Power on the ADC */
	cs428x_read_codec(sc, AC97_REG_POWER, &data);
	cs428x_write_codec(sc, AC97_REG_POWER, data & 0xfeff);

	/* Wait until we sample ADC ready state.
	 * Not documented, but Linux driver does.
	 */
	for (n = 0; n < 32; ++n) {
		delay(1000);
		cs428x_read_codec(sc, AC97_REG_POWER, &data);
		if (data & 0x01)
			break;
	}

#if 0
	/* Initialize AC-Link features */
	/* variable sample-rate support */
	mem = BA0READ4(sc, CS4281_SERMC);
	mem |=  (SERMC_ODSEN1 | SERMC_ODSEN2);
	BA0WRITE4(sc, CS4281_SERMC, mem);
	/* XXX: more... */

	/* Initialize SSCR register features */
	/* XXX: hardware volume setting */
	BA0WRITE4(sc, CS4281_SSCR, ~SSCR_HVC); /* disable HW volume setting */
#endif

	/* disable Sound Blaster Pro emulation */
	/* XXX:
	 * Cannot set since the documents does not describe which bit is
	 * correspond to SSCR_SB. Since the reset value of SSCR is 0,
	 * we can ignore it.*/
#if 0
	BA0WRITE4(sc, CS4281_SSCR, SSCR_SB);
#endif

	/* map AC97 PCM playback to DMA Channel 0 */
	/* Reset FEN bit to setup first */
	BA0WRITE4(sc, CS4281_FCR0, (BA0READ4(sc, CS4281_FCR0) & ~FCRn_FEN));
	/*
	 *| RS[4:0]/|        |
	 *| LS[4:0] |  AC97  | Slot Function
	 *|---------+--------+--------------------
	 *|     0   |    3   | Left PCM Playback
	 *|     1   |    4   | Right PCM Playback
	 *|     2   |    5   | Phone Line 1 DAC
	 *|     3   |    6   | Center PCM Playback
	 *....
	 *  quoted from Table 29(p109)
	 */
	dat32 = 0x01 << 24 |   /* RS[4:0] =  1 see above */
		0x00 << 16 |   /* LS[4:0] =  0 see above */
		0x0f <<  8 |   /* SZ[6:0] = 15 size of buffer */
		0x00 <<  0 ;   /* OF[6:0] =  0 offset */
	BA0WRITE4(sc, CS4281_FCR0, dat32);
	BA0WRITE4(sc, CS4281_FCR0, dat32 | FCRn_FEN);

	/* map AC97 PCM record to DMA Channel 1 */
	/* Reset FEN bit to setup first */
	BA0WRITE4(sc, CS4281_FCR1, (BA0READ4(sc, CS4281_FCR1) & ~FCRn_FEN));
	/*
	 *| RS[4:0]/|
	 *| LS[4:0] | AC97 | Slot Function
	 *|---------+------+-------------------
	 *|   10    |   3  | Left PCM Record
	 *|   11    |   4  | Right PCM Record
	 *|   12    |   5  | Phone Line 1 ADC
	 *|   13    |   6  | Mic ADC
	 *....
	 * quoted from Table 30(p109)
	 */
	dat32 = 0x0b << 24 |    /* RS[4:0] = 11 See above */
		0x0a << 16 |    /* LS[4:0] = 10 See above */
		0x0f <<  8 |    /* SZ[6:0] = 15 Size of buffer */
		0x10 <<  0 ;    /* OF[6:0] = 16 offset */

	/* XXX: I cannot understand why FCRn_PSH is needed here. */
	BA0WRITE4(sc, CS4281_FCR1, dat32 | FCRn_PSH);
	BA0WRITE4(sc, CS4281_FCR1, dat32 | FCRn_FEN);

#if 0
	/* Disable DMA Channel 2, 3 */
	BA0WRITE4(sc, CS4281_FCR2, (BA0READ4(sc, CS4281_FCR2) & ~FCRn_FEN));
	BA0WRITE4(sc, CS4281_FCR3, (BA0READ4(sc, CS4281_FCR3) & ~FCRn_FEN));
#endif

	/* Set the SRC Slot Assignment accordingly */
	/*| PLSS[4:0]/
	 *| PRSS[4:0] | AC97 | Slot Function
	 *|-----------+------+----------------
	 *|     0     |  3   | Left PCM Playback
	 *|     1     |  4   | Right PCM Playback
	 *|     2     |  5   | phone line 1 DAC
	 *|     3     |  6   | Center PCM Playback
	 *|     4     |  7   | Left Surround PCM Playback
	 *|     5     |  8   | Right Surround PCM Playback
	 *......
	 *
	 *| CLSS[4:0]/
	 *| CRSS[4:0] | AC97 | Codec |Slot Function
	 *|-----------+------+-------+-----------------
	 *|    10     |   3  |Primary| Left PCM Record
	 *|    11     |   4  |Primary| Right PCM Record
	 *|    12     |   5  |Primary| Phone Line 1 ADC
	 *|    13     |   6  |Primary| Mic ADC
	 *|.....
	 *|    20     |   3  |  Sec. | Left PCM Record
	 *|    21     |   4  |  Sec. | Right PCM Record
	 *|    22     |   5  |  Sec. | Phone Line 1 ADC
	 *|    23     |   6  |  Sec. | Mic ADC
	 */
	dat32 = 0x0b << 24 |   /* CRSS[4:0] Right PCM Record(primary) */
		0x0a << 16 |   /* CLSS[4:0] Left  PCM Record(primary) */
		0x01 <<  8 |   /* PRSS[4:0] Right PCM Playback */
		0x00 <<  0;    /* PLSS[4:0] Left  PCM Playback */
	BA0WRITE4(sc, CS4281_SRCSA, dat32);

	/* Set interrupt to occurred at Half and Full terminal
	 * count interrupt enable for DMA channel 0 and 1.
	 * To keep DMA stop, set MSK.
	 */
	dat32 = DCRn_HTCIE | DCRn_TCIE | DCRn_MSK;
	BA0WRITE4(sc, CS4281_DCR0, dat32);
	BA0WRITE4(sc, CS4281_DCR1, dat32);

	/* Set Auto-Initialize Control enable */
	BA0WRITE4(sc, CS4281_DMR0,
		  DMRn_DMA | DMRn_AUTO | DMRn_TR_READ);
	BA0WRITE4(sc, CS4281_DMR1,
		  DMRn_DMA | DMRn_AUTO | DMRn_TR_WRITE);

	/* Clear DMA Mask in HIMR */
	dat32 = ~HIMR_DMAIM & ~HIMR_D1IM & ~HIMR_D0IM;
	BA0WRITE4(sc, CS4281_HIMR,
		  BA0READ4(sc, CS4281_HIMR) & dat32);

	/* set current status */
	if (init != 0) {
		sc->sc_prun = 0;
		sc->sc_rrun = 0;
	}

	/* setup playback volume */
	BA0WRITE4(sc, CS4281_PPRVC, 7);
	BA0WRITE4(sc, CS4281_PPLVC, 7);

	return 0;
}