source: GPL/trunk/alsa-kernel/pci/es1968.c@ 260

/*
 *  Driver for ESS Maestro 1/2/2E Sound Card (started 21.8.99)
 *  Copyright (c) by Matze Braun <MatzeBraun@gmx.de>.
 *                   Takashi Iwai <tiwai@suse.de>
 *
 *  Most of the driver code comes from Zach Brown(zab@redhat.com)
 *      Alan Cox OSS Driver
 *  Rewritted from card-es1938.c source.
 *
 *  TODO:
 *   Perhaps Synth
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 *
 *  Notes from Zach Brown about the driver code
 *
 *  Hardware Description
 *
 *      A working Maestro setup contains the Maestro chip wired to a
 *      codec or 2.  In the Maestro we have the APUs, the ASSP, and the
 *      Wavecache.  The APUs can be though of as virtual audio routing
 *      channels.  They can take data from a number of sources and perform
 *      basic encodings of the data.  The wavecache is a storehouse for
 *      PCM data.  Typically it deals with PCI and interracts with the
 *      APUs.  The ASSP is a wacky DSP like device that ESS is loth
 *      to release docs on.  Thankfully it isn't required on the Maestro
 *      until you start doing insane things like FM emulation and surround
 *      encoding.  The codecs are almost always AC-97 compliant codecs,
 *      but it appears that early Maestros may have had PT101 (an ESS
 *      part?) wired to them.  The only real difference in the Maestro
 *      families is external goop like docking capability, memory for
 *      the ASSP, and initialization differences.
 *
 *  Driver Operation
 *
 *      We only drive the APU/Wavecache as typical DACs and drive the
 *      mixers in the codecs.  There are 64 APUs.  We assign 6 to each
 *      /dev/dsp? device.  2 channels for output, and 4 channels for
 *      input.
 *
 *      Each APU can do a number of things, but we only really use
 *      3 basic functions.  For playback we use them to convert PCM
 *      data fetched over PCI by the wavecahche into analog data that
 *      is handed to the codec.  One APU for mono, and a pair for stereo.
 *      When in stereo, the combination of smarts in the APU and Wavecache
 *      decide which wavecache gets the left or right channel.
 *
 *      For record we still use the old overly mono system.  For each in
 *      coming channel the data comes in from the codec, through a 'input'
 *      APU, through another rate converter APU, and then into memory via
 *      the wavecache and PCI.  If its stereo, we mash it back into LRLR in
 *      software.  The pass between the 2 APUs is supposedly what requires us
 *      to have a 512 byte buffer sitting around in wavecache/memory.
 *
 *      The wavecache makes our life even more fun.  First off, it can
 *      only address the first 28 bits of PCI address space, making it
 *      useless on quite a few architectures.  Secondly, its insane.
 *      It claims to fetch from 4 regions of PCI space, each 4 meg in length.
 *      But that doesn't really work.  You can only use 1 region.  So all our
 *      allocations have to be in 4meg of each other.  Booo.  Hiss.
 *      So we have a module parameter, dsps_order, that is the order of
 *      the number of dsps to provide.  All their buffer space is allocated
 *      on open time.  The sonicvibes OSS routines we inherited really want
 *      power of 2 buffers, so we have all those next to each other, then
 *      512 byte regions for the recording wavecaches.  This ends up
 *      wasting quite a bit of memory.  The only fixes I can see would be
 *      getting a kernel allocator that could work in zones, or figuring out
 *      just how to coerce the WP into doing what we want.
 *
 *      The indirection of the various registers means we have to spinlock
 *      nearly all register accesses.  We have the main register indirection
 *      like the wave cache, maestro registers, etc.  Then we have beasts
 *      like the APU interface that is indirect registers gotten at through
 *      the main maestro indirection.  Ouch.  We spinlock around the actual
 *      ports on a per card basis.  This means spinlock activity at each IO
 *      operation, but the only IO operation clusters are in non critical
 *      paths and it makes the code far easier to follow.  Interrupts are
 *      blocked while holding the locks because the int handler has to
 *      get at some of them :(.  The mixer interface doesn't, however.
 *      We also have an OSS state lock that is thrown around in a few
 *      places.
 */

#define __SND_OSS_COMPAT__
#include <sound/driver.h>
#include <sound/pcm.h>
#include <sound/mpu401.h>
#include <sound/ac97_codec.h>
#define SNDRV_GET_ID
#include <sound/initval.h>

#define CARD_NAME "ESS Maestro1/2"
#define DRIVER_NAME "ES1968"

EXPORT_NO_SYMBOLS;
MODULE_DESCRIPTION("ESS Maestro");
MODULE_CLASSES("{sound}");
MODULE_LICENSE("GPL");
MODULE_DEVICES("{{ESS,Maestro 2e},"
               "{ESS,Maestro 2},"
               "{ESS,Maestro 1},"
               "{TerraTec,DMX}}");

static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;      /* Index 1-MAX */
static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;       /* ID for this card */
static int enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP;      /* Enable this card */
static int total_bufsize[SNDRV_CARDS] = { REPEAT_SNDRV(1024) };
static int pcm_substreams_p[SNDRV_CARDS] = { REPEAT_SNDRV(4) };
static int pcm_substreams_c[SNDRV_CARDS] = { REPEAT_SNDRV(1) };
static int clock[SNDRV_CARDS] = { REPEAT_SNDRV(0) };
static int use_pm[SNDRV_CARDS] = { REPEAT_SNDRV(2) };
static int enable_mpu[SNDRV_CARDS] = { REPEAT_SNDRV(1) };

MODULE_PARM(index, "1-" __MODULE_STRING(SNDRV_CARDS) "i");
MODULE_PARM_DESC(index, "Index value for " CARD_NAME " soundcard.");
MODULE_PARM_SYNTAX(index, SNDRV_INDEX_DESC);
MODULE_PARM(id, "1-" __MODULE_STRING(SNDRV_CARDS) "s");
MODULE_PARM_DESC(id, "ID string for " CARD_NAME " soundcard.");
MODULE_PARM_SYNTAX(id, SNDRV_ID_DESC);
MODULE_PARM(enable, "1-" __MODULE_STRING(SNDRV_CARDS) "i");
MODULE_PARM_DESC(enable, "Enable " CARD_NAME " soundcard.");
MODULE_PARM_SYNTAX(enable, SNDRV_ENABLE_DESC);
MODULE_PARM(total_bufsize, "1-" __MODULE_STRING(SNDRV_CARDS) "i");
MODULE_PARM_DESC(total_bufsize, "Total buffer size in kB.");
MODULE_PARM_SYNTAX(total_bufsize, SNDRV_ENABLED ",allows:{{1,4096}},skill:advanced");
MODULE_PARM(pcm_substreams_p, "1-" __MODULE_STRING(SNDRV_CARDS) "i");
MODULE_PARM_DESC(pcm_substreams_p, "PCM Playback substreams for " CARD_NAME " soundcard.");
MODULE_PARM_SYNTAX(pcm_substreams_p, SNDRV_ENABLED ",allows:{{1,8}}");
MODULE_PARM(pcm_substreams_c, "1-" __MODULE_STRING(SNDRV_CARDS) "i");
MODULE_PARM_DESC(pcm_substreams_c, "PCM Capture substreams for " CARD_NAME " soundcard.");
MODULE_PARM_SYNTAX(pcm_substreams_c, SNDRV_ENABLED ",allows:{{0,8}}");
MODULE_PARM(clock, "1-" __MODULE_STRING(SNDRV_CARDS) "i");
MODULE_PARM_DESC(clock, "Clock on " CARD_NAME " soundcard.  (0 = auto-detect)");
MODULE_PARM_SYNTAX(clock, SNDRV_ENABLED);
MODULE_PARM(use_pm, "1-" __MODULE_STRING(SNDRV_CARDS) "i");
MODULE_PARM_DESC(use_pm, "Toggle power-management.  (0 = off, 1 = on, 2 = auto)");
MODULE_PARM_SYNTAX(use_pm, SNDRV_ENABLED ",allows:{{0,1,2}},skill:advanced");
MODULE_PARM(enable_mpu, "1-" __MODULE_STRING(SNDRV_CARDS) "i");
MODULE_PARM_DESC(enable_mpu, "Enable MPU401.  (0 = off, 1 = on, 2 = auto)");
MODULE_PARM_SYNTAX(enable_mpu, SNDRV_ENABLED "," SNDRV_BOOLEAN_TRUE_DESC);


/* PCI Dev ID's */

#ifndef PCI_VENDOR_ID_ESS
#define PCI_VENDOR_ID_ESS       0x125D
#endif

#define PCI_VENDOR_ID_ESS_OLD   0x1285  /* Platform Tech, the people the ESS
was bought form */

#ifndef PCI_DEVICE_ID_ESS_M2E
#define PCI_DEVICE_ID_ESS_M2E   0x1978
#endif
#ifndef PCI_DEVICE_ID_ESS_M2
#define PCI_DEVICE_ID_ESS_M2    0x1968
#endif
#ifndef PCI_DEVICE_ID_ESS_M1
#define PCI_DEVICE_ID_ESS_M1    0x0100
#endif

#define NR_APUS                 64
#define NR_APU_REGS             16

/* NEC Versas ? */
#define NEC_VERSA_SUBID1        0x80581033
#define NEC_VERSA_SUBID2        0x803c1033

/* Mode Flags */
#define ESS_FMT_STEREO          0x01
#define ESS_FMT_16BIT           0x02

#define DAC_RUNNING             1
#define ADC_RUNNING             2

/* Values for the ESM_LEGACY_AUDIO_CONTROL */

#define ESS_ENABLE_AUDIO        0x8000
#define ESS_ENABLE_SERIAL_IRQ   0x4000
#define IO_ADRESS_ALIAS         0x0020
#define MPU401_IRQ_ENABLE       0x0010
#define MPU401_IO_ENABLE        0x0008
#define GAME_IO_ENABLE          0x0004
#define FM_IO_ENABLE            0x0002
#define SB_IO_ENABLE            0x0001

/* Values for the ESM_CONFIG_A */

#define PIC_SNOOP1              0x4000
#define PIC_SNOOP2              0x2000
#define SAFEGUARD               0x0800
#define DMA_CLEAR               0x0700
#define DMA_DDMA                0x0000
#define DMA_TDMA                0x0100
#define DMA_PCPCI               0x0200
#define POST_WRITE              0x0080
#define ISA_TIMING              0x0040
#define SWAP_LR                 0x0020
#define SUBTR_DECODE            0x0002

/* Values for the ESM_CONFIG_B */

#define SPDIF_CONFB             0x0100
#define HWV_CONFB               0x0080
#define DEBOUNCE                0x0040
#define GPIO_CONFB              0x0020
#define CHI_CONFB               0x0010
#define IDMA_CONFB              0x0008  /*undoc */
#define MIDI_FIX                0x0004  /*undoc */
#define IRQ_TO_ISA              0x0001  /*undoc */

/* Values for Ring Bus Control B */
#define RINGB_2CODEC_ID_MASK    0x0003
#define RINGB_DIS_VALIDATION    0x0008
#define RINGB_EN_SPDIF          0x0010
#define RINGB_EN_2CODEC         0x0020
#define RINGB_SING_BIT_DUAL     0x0040

/* ****Port Adresses**** */

/*   Write & Read */
#define ESM_INDEX               0x02
#define ESM_DATA                0x00

/*   AC97 + RingBus */
#define ESM_AC97_INDEX          0x30
#define ESM_AC97_DATA           0x32
#define ESM_RING_BUS_DEST       0x34
#define ESM_RING_BUS_CONTR_A    0x36
#define ESM_RING_BUS_CONTR_B    0x38
#define ESM_RING_BUS_SDO        0x3A

/*   WaveCache*/
#define WC_INDEX                0x10
#define WC_DATA                 0x12
#define WC_CONTROL              0x14

/*   ASSP*/
#define ASSP_INDEX              0x80
#define ASSP_MEMORY             0x82
#define ASSP_DATA               0x84
#define ASSP_CONTROL_A          0xA2
#define ASSP_CONTROL_B          0xA4
#define ASSP_CONTROL_C          0xA6
#define ASSP_HOSTW_INDEX        0xA8
#define ASSP_HOSTW_DATA         0xAA
#define ASSP_HOSTW_IRQ          0xAC
/* Midi */
#define ESM_MPU401_PORT         0x98
/* Others */
#define ESM_PORT_HOST_IRQ       0x18

#define IDR0_DATA_PORT          0x00
#define IDR1_CRAM_POINTER       0x01
#define IDR2_CRAM_DATA          0x02
#define IDR3_WAVE_DATA          0x03
#define IDR4_WAVE_PTR_LOW       0x04
#define IDR5_WAVE_PTR_HI        0x05
#define IDR6_TIMER_CTRL         0x06
#define IDR7_WAVE_ROMRAM        0x07

#define WRITEABLE_MAP           0xEFFFFF
#define READABLE_MAP            0x64003F

/* PCI Register */

#define ESM_LEGACY_AUDIO_CONTROL 0x40
#define ESM_ACPI_COMMAND        0x54
#define ESM_CONFIG_A            0x50
#define ESM_CONFIG_B            0x52
#define ESM_DDMA                0x60

/* Bob Bits */
#define ESM_BOB_ENABLE          0x0001
#define ESM_BOB_START           0x0001

/* Host IRQ Control Bits */
#define ESM_RESET_MAESTRO       0x8000
#define ESM_RESET_DIRECTSOUND   0x4000
#define ESM_HIRQ_ClkRun         0x0100
#define ESM_HIRQ_HW_VOLUME      0x0040
#define ESM_HIRQ_HARPO          0x0030  /* What's that? */
#define ESM_HIRQ_ASSP           0x0010
#define ESM_HIRQ_DSIE           0x0004
#define ESM_HIRQ_MPU401         0x0002
#define ESM_HIRQ_SB             0x0001

/* Host IRQ Status Bits */
#define ESM_MPU401_IRQ          0x02
#define ESM_SB_IRQ              0x01
#define ESM_SOUND_IRQ           0x04
#define ESM_ASSP_IRQ            0x10
#define ESM_HWVOL_IRQ           0x40

#define ESS_SYSCLK              50000000
#define ESM_BOB_FREQ            200
#define ESM_BOB_FREQ_MAX        800

#define ESM_FREQ_ESM1           (49152000L / 1024L)     /* default rate 48000 */
#define ESM_FREQ_ESM2           (50000000L / 1024L)

/* APU Modes: reg 0x00, bit 4-7 */
#define ESM_APU_MODE_SHIFT      4
#define ESM_APU_MODE_MASK       (0xf << 4)
#define ESM_APU_OFF             0x00
#define ESM_APU_16BITLINEAR     0x01    /* 16-Bit Linear Sample Player */
#define ESM_APU_16BITSTEREO     0x02    /* 16-Bit Stereo Sample Player */
#define ESM_APU_8BITLINEAR      0x03    /* 8-Bit Linear Sample Player */
#define ESM_APU_8BITSTEREO      0x04    /* 8-Bit Stereo Sample Player */
#define ESM_APU_8BITDIFF        0x05    /* 8-Bit Differential Sample Playrer */
#define ESM_APU_DIGITALDELAY    0x06    /* Digital Delay Line */
#define ESM_APU_DUALTAP         0x07    /* Dual Tap Reader */
#define ESM_APU_CORRELATOR      0x08    /* Correlator */
#define ESM_APU_INPUTMIXER      0x09    /* Input Mixer */
#define ESM_APU_WAVETABLE       0x0A    /* Wave Table Mode */
#define ESM_APU_SRCONVERTOR     0x0B    /* Sample Rate Convertor */
#define ESM_APU_16BITPINGPONG   0x0C    /* 16-Bit Ping-Pong Sample Player */
#define ESM_APU_RESERVED1       0x0D    /* Reserved 1 */
#define ESM_APU_RESERVED2       0x0E    /* Reserved 2 */
#define ESM_APU_RESERVED3       0x0F    /* Reserved 3 */

/* reg 0x00 */
#define ESM_APU_FILTER_Q_SHIFT          0
#define ESM_APU_FILTER_Q_MASK           (3 << 0)
/* APU Filtey Q Control */
#define ESM_APU_FILTER_LESSQ    0x00
#define ESM_APU_FILTER_MOREQ    0x03

#define ESM_APU_FILTER_TYPE_SHIFT       2
#define ESM_APU_FILTER_TYPE_MASK        (3 << 2)
#define ESM_APU_ENV_TYPE_SHIFT          8
#define ESM_APU_ENV_TYPE_MASK           (3 << 8)
#define ESM_APU_ENV_STATE_SHIFT         10
#define ESM_APU_ENV_STATE_MASK          (3 << 10)
#define ESM_APU_END_CURVE               (1 << 12)
#define ESM_APU_INT_ON_LOOP             (1 << 13)
#define ESM_APU_DMA_ENABLE              (1 << 14)

/* reg 0x02 */
#define ESM_APU_SUBMIX_GROUP_SHIRT      0
#define ESM_APU_SUBMIX_GROUP_MASK       (7 << 0)
#define ESM_APU_SUBMIX_MODE             (1 << 3)
#define ESM_APU_6dB                     (1 << 4)
#define ESM_APU_DUAL_EFFECT             (1 << 5)
#define ESM_APU_EFFECT_CHANNELS_SHIFT   6
#define ESM_APU_EFFECT_CHANNELS_MASK    (3 << 6)

/* reg 0x03 */
#define ESM_APU_STEP_SIZE_MASK          0x0fff

/* reg 0x04 */
#define ESM_APU_PHASE_SHIFT             0
#define ESM_APU_PHASE_MASK              (0xff << 0)
#define ESM_APU_WAVE64K_PAGE_SHIFT      8       /* most 8bit of wave start offset */
#define ESM_APU_WAVE64K_PAGE_MASK       (0xff << 8)

/* reg 0x05 - wave start offset */
/* reg 0x06 - wave end offset */
/* reg 0x07 - wave loop length */

/* reg 0x08 */
#define ESM_APU_EFFECT_GAIN_SHIFT       0
#define ESM_APU_EFFECT_GAIN_MASK        (0xff << 0)
#define ESM_APU_TREMOLO_DEPTH_SHIFT     8
#define ESM_APU_TREMOLO_DEPTH_MASK      (0xf << 8)
#define ESM_APU_TREMOLO_RATE_SHIFT      12
#define ESM_APU_TREMOLO_RATE_MASK       (0xf << 12)

/* reg 0x09 */
/* bit 0-7 amplitude dest? */
#define ESM_APU_AMPLITUDE_NOW_SHIFT     8
#define ESM_APU_AMPLITUDE_NOW_MASK      (0xff << 8)

/* reg 0x0a */
#define ESM_APU_POLAR_PAN_SHIFT         0
#define ESM_APU_POLAR_PAN_MASK          (0x3f << 0)
/* Polar Pan Control */
#define ESM_APU_PAN_CENTER_CIRCLE               0x00
#define ESM_APU_PAN_MIDDLE_RADIUS               0x01
#define ESM_APU_PAN_OUTSIDE_RADIUS              0x02

#define ESM_APU_FILTER_TUNING_SHIFT     8
#define ESM_APU_FILTER_TUNING_MASK      (0xff << 8)

/* reg 0x0b */
#define ESM_APU_DATA_SRC_A_SHIFT        0
#define ESM_APU_DATA_SRC_A_MASK         (0x7f << 0)
#define ESM_APU_INV_POL_A               (1 << 7)
#define ESM_APU_DATA_SRC_B_SHIFT        8
#define ESM_APU_DATA_SRC_B_MASK         (0x7f << 8)
#define ESM_APU_INV_POL_B               (1 << 15)

#define ESM_APU_VIBRATO_RATE_SHIFT      0
#define ESM_APU_VIBRATO_RATE_MASK       (0xf << 0)
#define ESM_APU_VIBRATO_DEPTH_SHIFT     4
#define ESM_APU_VIBRATO_DEPTH_MASK      (0xf << 4)
#define ESM_APU_VIBRATO_PHASE_SHIFT     8
#define ESM_APU_VIBRATO_PHASE_MASK      (0xff << 8)

/* reg 0x0c */
#define ESM_APU_RADIUS_SELECT           (1 << 6)

/* APU Filter Control */
#define ESM_APU_FILTER_2POLE_LOPASS     0x00
#define ESM_APU_FILTER_2POLE_BANDPASS   0x01
#define ESM_APU_FILTER_2POLE_HIPASS     0x02
#define ESM_APU_FILTER_1POLE_LOPASS     0x03
#define ESM_APU_FILTER_1POLE_HIPASS     0x04
#define ESM_APU_FILTER_OFF              0x05

/* APU ATFP Type */
#define ESM_APU_ATFP_AMPLITUDE                  0x00
#define ESM_APU_ATFP_TREMELO                    0x01
#define ESM_APU_ATFP_FILTER                     0x02
#define ESM_APU_ATFP_PAN                        0x03

/* APU ATFP Flags */
#define ESM_APU_ATFP_FLG_OFF                    0x00
#define ESM_APU_ATFP_FLG_WAIT                   0x01
#define ESM_APU_ATFP_FLG_DONE                   0x02
#define ESM_APU_ATFP_FLG_INPROCESS              0x03


/* capture mixing buffer size */
#define ESM_MEM_ALIGN           0x1000
#define ESM_MIXBUF_SIZE         0x400

#define ESM_MODE_PLAY           0
#define ESM_MODE_CAPTURE        1

/* acpi states */
enum {
    ACPI_D0=0,
    ACPI_D1,
    ACPI_D2,
    ACPI_D3
};

/* bits in the acpi masks */
#define ACPI_12MHZ      ( 1 << 15)
#define ACPI_24MHZ      ( 1 << 14)
#define ACPI_978        ( 1 << 13)
#define ACPI_SPDIF      ( 1 << 12)
#define ACPI_GLUE       ( 1 << 11)
#define ACPI__10        ( 1 << 10) /* reserved */
#define ACPI_PCIINT     ( 1 << 9)
#define ACPI_HV         ( 1 << 8) /* hardware volume */
#define ACPI_GPIO       ( 1 << 7)
#define ACPI_ASSP       ( 1 << 6)
#define ACPI_SB         ( 1 << 5) /* sb emul */
#define ACPI_FM         ( 1 << 4) /* fm emul */
#define ACPI_RB         ( 1 << 3) /* ringbus / aclink */
#define ACPI_MIDI       ( 1 << 2)
#define ACPI_GP         ( 1 << 1) /* game port */
#define ACPI_WP         ( 1 << 0) /* wave processor */

#define ACPI_ALL        (0xffff)
#define ACPI_SLEEP      (~(ACPI_SPDIF|ACPI_ASSP|ACPI_SB|ACPI_FM| \
    ACPI_MIDI|ACPI_GP|ACPI_WP))
#define ACPI_NONE       (ACPI__10)

/* these masks indicate which units we care about at
 which states */
static u16 acpi_state_mask[] = {
#ifdef TARGET_OS2
    ACPI_ALL,
    ACPI_SLEEP,
    ACPI_SLEEP,
    ACPI_NONE
#else
    [ACPI_D0] = ACPI_ALL,
    [ACPI_D1] = ACPI_SLEEP,
    [ACPI_D2] = ACPI_SLEEP,
    [ACPI_D3] = ACPI_NONE
#endif
};


typedef struct snd_es1968 es1968_t;
typedef struct snd_esschan esschan_t;
typedef struct snd_esm_memory esm_memory_t;

/* APU use in the driver */
enum snd_enum_apu_type {
    ESM_APU_PCM_PLAY,
    ESM_APU_PCM_CAPTURE,
    ESM_APU_PCM_RATECONV,
    ESM_APU_FREE
};

/* chip type */
enum {
    TYPE_MAESTRO, TYPE_MAESTRO2, TYPE_MAESTRO2E
};

/* DMA Hack! */
struct snd_esm_memory {
    struct snd_dma_buffer buf;
    int empty;  /* status */
    struct list_head list;
};

/* Playback Channel */
struct snd_esschan {
    int running;

    u8 apu[4];
    u8 apu_mode[4];

    /* playback/capture pcm buffer */
    esm_memory_t *memory;
    /* capture mixer buffer */
    esm_memory_t *mixbuf;

    unsigned int hwptr; /* current hw pointer in bytes */
    unsigned int count; /* sample counter in bytes */
    unsigned int dma_size;      /* total buffer size in bytes */
    unsigned int frag_size;     /* period size in bytes */
    unsigned int wav_shift;
    u16 base[4];                /* offset for ptr */

    /* stereo/16bit flag */
    unsigned char fmt;
    int mode;   /* playback / capture */

    int bob_freq;       /* required timer frequency */

    snd_pcm_substream_t *substream;

    /* linked list */
    struct list_head list;

#ifdef CONFIG_PM
    u16 wc_map[4];
#endif
};

struct snd_es1968 {
    /* Module Config */
    int total_bufsize;                  /* in bytes */

    int playback_streams, capture_streams;

    unsigned int clock;         /* clock */
    /* for clock measurement */
    unsigned int in_measurement: 1;
    unsigned int measure_apu;
    unsigned int measure_lastpos;
    unsigned int measure_count;

    /* buffer */
    struct snd_dma_buffer dma;

    /* Resources... */
    int irq;
    unsigned long io_port;
    int type;
    struct pci_dev *pci;
    snd_card_t *card;
    snd_pcm_t *pcm;
    int do_pm;          /* power-management enabled */

    /* DMA memory block */
    struct list_head buf_list;

    /* ALSA Stuff */
    ac97_t *ac97;
    snd_kcontrol_t *master_switch; /* for h/w volume control */
    snd_kcontrol_t *master_volume;

    snd_rawmidi_t *rmidi;

    spinlock_t reg_lock;
    spinlock_t ac97_lock;
    struct tasklet_struct hwvol_tq;
    unsigned int in_suspend;

    /* Maestro Stuff */
    u16 maestro_map[32];
    int bobclient;              /* active timer instancs */
    int bob_freq;               /* timer frequency */
    struct semaphore memory_mutex;      /* memory lock */

    /* APU states */
    unsigned char apu[NR_APUS];

    /* active substreams */
    struct list_head substream_list;
    spinlock_t substream_lock;

#ifdef CONFIG_PM
    u16 apu_map[NR_APUS][NR_APU_REGS];
#endif
};

static irqreturn_t snd_es1968_interrupt(int irq, void *dev_id, struct pt_regs *regs);

static struct pci_device_id snd_es1968_ids[] = {
    /* Maestro 1 */
    { 0x1285, 0x0100, PCI_ANY_ID, PCI_ANY_ID, PCI_CLASS_MULTIMEDIA_AUDIO << 8, 0xffff00, TYPE_MAESTRO },
    /* Maestro 2 */
    { 0x125d, 0x1968, PCI_ANY_ID, PCI_ANY_ID, PCI_CLASS_MULTIMEDIA_AUDIO << 8, 0xffff00, TYPE_MAESTRO2 },
    /* Maestro 2E */
    { 0x125d, 0x1978, PCI_ANY_ID, PCI_ANY_ID, PCI_CLASS_MULTIMEDIA_AUDIO << 8, 0xffff00, TYPE_MAESTRO2E },
    { 0, }
};

MODULE_DEVICE_TABLE(pci, snd_es1968_ids);

/* *********************
 * Low Level Funcs!  *
 *********************/

/* no spinlock */
static void __maestro_write(es1968_t *chip, u16 reg, u16 data)
{
    outw(reg, chip->io_port + ESM_INDEX);
    outw(data, chip->io_port + ESM_DATA);
    chip->maestro_map[reg] = data;
}

inline static void maestro_write(es1968_t *chip, u16 reg, u16 data)
{
    unsigned long flags;
    spin_lock_irqsave(&chip->reg_lock, flags);
    __maestro_write(chip, reg, data);
    spin_unlock_irqrestore(&chip->reg_lock, flags);
}

/* no spinlock */
static u16 __maestro_read(es1968_t *chip, u16 reg)
{
    if (READABLE_MAP & (1 << reg)) {
        outw(reg, chip->io_port + ESM_INDEX);
        chip->maestro_map[reg] = inw(chip->io_port + ESM_DATA);
    }
    return chip->maestro_map[reg];
}

inline static u16 maestro_read(es1968_t *chip, u16 reg)
{
    unsigned long flags;
    u16 result;
    spin_lock_irqsave(&chip->reg_lock, flags);
    result = __maestro_read(chip, reg);
    spin_unlock_irqrestore(&chip->reg_lock, flags);
    return result;
}

/* Wait for the codec bus to be free */
static int snd_es1968_ac97_wait(es1968_t *chip)
{
    int timeout = 100000;

    while (timeout-- > 0) {
        if (!(inb(chip->io_port + ESM_AC97_INDEX) & 1))
            return 0;
        cond_resched();
    }
    snd_printd("es1968: ac97 timeout\n");
    return 1; /* timeout */
}

static void snd_es1968_ac97_write(ac97_t *ac97, unsigned short reg, unsigned short val)
{
    es1968_t *chip = ac97->private_data;
    unsigned long flags;

    snd_es1968_ac97_wait(chip);

    /* Write the bus */
    spin_lock_irqsave(&chip->ac97_lock, flags);
    outw(val, chip->io_port + ESM_AC97_DATA);
    /*msleep(1);*/
    outb(reg, chip->io_port + ESM_AC97_INDEX);
    /*msleep(1);*/
    spin_unlock_irqrestore(&chip->ac97_lock, flags);
}

static unsigned short snd_es1968_ac97_read(ac97_t *ac97, unsigned short reg)
{
    u16 data = 0;
    es1968_t *chip = ac97->private_data;
    unsigned long flags;

    snd_es1968_ac97_wait(chip);

    spin_lock_irqsave(&chip->ac97_lock, flags);
    outb(reg | 0x80, chip->io_port + ESM_AC97_INDEX);
    /*msleep(1);*/

    if (! snd_es1968_ac97_wait(chip)) {
        data = inw(chip->io_port + ESM_AC97_DATA);
        /*msleep(1);*/
    }
    spin_unlock_irqrestore(&chip->ac97_lock, flags);

    return data;
}

/* no spinlock */
static void apu_index_set(es1968_t *chip, u16 index)
{
    int i;
    __maestro_write(chip, IDR1_CRAM_POINTER, index);
    for (i = 0; i < 1000; i++)
        if (__maestro_read(chip, IDR1_CRAM_POINTER) == index)
            return;
    snd_printd("es1968: APU register select failed. (Timeout)\n");
}

/* no spinlock */
static void apu_data_set(es1968_t *chip, u16 data)
{
    int i;
    for (i = 0; i < 1000; i++) {
        if (__maestro_read(chip, IDR0_DATA_PORT) == data)
            return;
        __maestro_write(chip, IDR0_DATA_PORT, data);
    }
    snd_printd("es1968: APU register set probably failed (Timeout)!\n");
}

/* no spinlock */
static void __apu_set_register(es1968_t *chip, u16 channel, u8 reg, u16 data)
{
    snd_assert(channel < NR_APUS, return);
#ifdef CONFIG_PM
    chip->apu_map[channel][reg] = data;
#endif
    reg |= (channel << 4);
    apu_index_set(chip, reg);
    apu_data_set(chip, data);
}

inline static void apu_set_register(es1968_t *chip, u16 channel, u8 reg, u16 data)
{
    unsigned long flags;
    spin_lock_irqsave(&chip->reg_lock, flags);
    __apu_set_register(chip, channel, reg, data);
    spin_unlock_irqrestore(&chip->reg_lock, flags);
}

static u16 __apu_get_register(es1968_t *chip, u16 channel, u8 reg)
{
    snd_assert(channel < NR_APUS, return 0);
    reg |= (channel << 4);
    apu_index_set(chip, reg);
    return __maestro_read(chip, IDR0_DATA_PORT);
}

inline static u16 apu_get_register(es1968_t *chip, u16 channel, u8 reg)
{
    unsigned long flags;
    u16 v;
    spin_lock_irqsave(&chip->reg_lock, flags);
    v = __apu_get_register(chip, channel, reg);
    spin_unlock_irqrestore(&chip->reg_lock, flags);
    return v;
}

#if 0 /* ASSP is not supported */

static void assp_set_register(es1968_t *chip, u32 reg, u32 value)
{
    unsigned long flags;

    spin_lock_irqsave(&chip->reg_lock, flags);
    outl(reg, chip->io_port + ASSP_INDEX);
    outl(value, chip->io_port + ASSP_DATA);
    spin_unlock_irqrestore(&chip->reg_lock, flags);
}

static u32 assp_get_register(es1968_t *chip, u32 reg)
{
    unsigned long flags;
    u32 value;

    spin_lock_irqsave(&chip->reg_lock, flags);
    outl(reg, chip->io_port + ASSP_INDEX);
    value = inl(chip->io_port + ASSP_DATA);
    spin_unlock_irqrestore(&chip->reg_lock, flags);

    return value;
}

#endif

static void wave_set_register(es1968_t *chip, u16 reg, u16 value)
{
    unsigned long flags;

    spin_lock_irqsave(&chip->reg_lock, flags);
    outw(reg, chip->io_port + WC_INDEX);
    outw(value, chip->io_port + WC_DATA);
    spin_unlock_irqrestore(&chip->reg_lock, flags);
}

static u16 wave_get_register(es1968_t *chip, u16 reg)
{
    unsigned long flags;
    u16 value;

    spin_lock_irqsave(&chip->reg_lock, flags);
    outw(reg, chip->io_port + WC_INDEX);
    value = inw(chip->io_port + WC_DATA);
    spin_unlock_irqrestore(&chip->reg_lock, flags);

    return value;
}

/* *******************
 * Bob the Timer!  *
 *******************/

static void snd_es1968_bob_stop(es1968_t *chip)
{
    u16 reg;

    reg = __maestro_read(chip, 0x11);
    reg &= ~ESM_BOB_ENABLE;
    __maestro_write(chip, 0x11, reg);
    reg = __maestro_read(chip, 0x17);
    reg &= ~ESM_BOB_START;
    __maestro_write(chip, 0x17, reg);
}

static void snd_es1968_bob_start(es1968_t *chip)
{
    int prescale;
    int divide;

    /* compute ideal interrupt frequency for buffer size & play rate */
    /* first, find best prescaler value to match freq */
    for (prescale = 5; prescale < 12; prescale++)
        if (chip->bob_freq > (ESS_SYSCLK >> (prescale + 9)))
            break;

    /* next, back off prescaler whilst getting divider into optimum range */
    divide = 1;
    while ((prescale > 5) && (divide < 32)) {
        prescale--;
        divide <<= 1;
    }
    divide >>= 1;

    /* now fine-tune the divider for best match */
    for (; divide < 31; divide++)
        if (chip->bob_freq >
            ((ESS_SYSCLK >> (prescale + 9)) / (divide + 1))) break;

    /* divide = 0 is illegal, but don't let prescale = 4! */
    if (divide == 0) {
        divide++;
        if (prescale > 5)
            prescale--;
    } else if (divide > 1)
        divide--;

    __maestro_write(chip, 6, 0x9000 | (prescale << 5) | divide);        /* set reg */

    /* Now set IDR 11/17 */
    __maestro_write(chip, 0x11, __maestro_read(chip, 0x11) | 1);
    __maestro_write(chip, 0x17, __maestro_read(chip, 0x17) | 1);
}

/* call with substream spinlock */
static void snd_es1968_bob_inc(es1968_t *chip, int freq)
{
    chip->bobclient++;
    if (chip->bobclient == 1) {
        chip->bob_freq = freq;
        snd_es1968_bob_start(chip);
    } else if (chip->bob_freq < freq) {
        snd_es1968_bob_stop(chip);
        chip->bob_freq = freq;
        snd_es1968_bob_start(chip);
    }
}

/* call with substream spinlock */
static void snd_es1968_bob_dec(es1968_t *chip)
{
    chip->bobclient--;
    if (chip->bobclient <= 0)
        snd_es1968_bob_stop(chip);
    else if (chip->bob_freq > ESM_BOB_FREQ) {
        /* check reduction of timer frequency */
        struct list_head *p;
        int max_freq = ESM_BOB_FREQ;
        list_for_each(p, &chip->substream_list) {
            esschan_t *es = list_entry(p, esschan_t, list);
            if (max_freq < es->bob_freq)
                max_freq = es->bob_freq;
        }
        if (max_freq != chip->bob_freq) {
            snd_es1968_bob_stop(chip);
            chip->bob_freq = max_freq;
            snd_es1968_bob_start(chip);
        }
    }
}

static int
snd_es1968_calc_bob_rate(es1968_t *chip, esschan_t *es,
                         snd_pcm_runtime_t *runtime)
{
    /* we acquire 4 interrupts per period for precise control.. */
    int freq = runtime->rate * 4;
    if (es->fmt & ESS_FMT_STEREO)
        freq <<= 1;
    if (es->fmt & ESS_FMT_16BIT)
        freq <<= 1;
    freq /= es->frag_size;
    if (freq < ESM_BOB_FREQ)
        freq = ESM_BOB_FREQ;
    else if (freq > ESM_BOB_FREQ_MAX)
        freq = ESM_BOB_FREQ_MAX;
    return freq;
}


/*************
 *  PCM Part *
 *************/

static u32 snd_es1968_compute_rate(es1968_t *chip, u32 freq)
{
    u32 rate = (freq << 16) / chip->clock;
#if 0 /* XXX: do we need this? */
    if (rate > 0x10000)
        rate = 0x10000;
#endif
    return rate;
}

/* get current pointer */
inline static unsigned int
snd_es1968_get_dma_ptr(es1968_t *chip, esschan_t *es)
{
    unsigned int offset;

    offset = apu_get_register(chip, es->apu[0], 5);

    offset -= es->base[0];

    return (offset & 0xFFFE);   /* hardware is in words */
}

static void snd_es1968_apu_set_freq(es1968_t *chip, int apu, int freq)
{
    apu_set_register(chip, apu, 2,
                     (apu_get_register(chip, apu, 2) & 0x00FF) |
                     ((freq & 0xff) << 8) | 0x10);
    apu_set_register(chip, apu, 3, freq >> 8);
}

/* spin lock held */
inline static void snd_es1968_trigger_apu(es1968_t *esm, int apu, int mode)
{
    /* set the APU mode */
    __apu_set_register(esm, apu, 0,
                       (__apu_get_register(esm, apu, 0) & 0xff0f) |
                       (mode << 4));
}

static void snd_es1968_pcm_start(es1968_t *chip, esschan_t *es)
{
    spin_lock(&chip->reg_lock);
    __apu_set_register(chip, es->apu[0], 5, es->base[0]);
    snd_es1968_trigger_apu(chip, es->apu[0], es->apu_mode[0]);
    if (es->mode == ESM_MODE_CAPTURE) {
        __apu_set_register(chip, es->apu[2], 5, es->base[2]);
        snd_es1968_trigger_apu(chip, es->apu[2], es->apu_mode[2]);
    }
    if (es->fmt & ESS_FMT_STEREO) {
        __apu_set_register(chip, es->apu[1], 5, es->base[1]);
        snd_es1968_trigger_apu(chip, es->apu[1], es->apu_mode[1]);
        if (es->mode == ESM_MODE_CAPTURE) {
            __apu_set_register(chip, es->apu[3], 5, es->base[3]);
            snd_es1968_trigger_apu(chip, es->apu[3], es->apu_mode[3]);
        }
    }
    spin_unlock(&chip->reg_lock);
}

static void snd_es1968_pcm_stop(es1968_t *chip, esschan_t *es)
{
    spin_lock(&chip->reg_lock);
    snd_es1968_trigger_apu(chip, es->apu[0], 0);
    snd_es1968_trigger_apu(chip, es->apu[1], 0);
    if (es->mode == ESM_MODE_CAPTURE) {
        snd_es1968_trigger_apu(chip, es->apu[2], 0);
        snd_es1968_trigger_apu(chip, es->apu[3], 0);
    }
    spin_unlock(&chip->reg_lock);
}

/* set the wavecache control reg */
static void snd_es1968_program_wavecache(es1968_t *chip, esschan_t *es,
                                         int channel, u32 addr, int capture)
{
    u32 tmpval = (addr - 0x10) & 0xFFF8;

    if (! capture) {
        if (!(es->fmt & ESS_FMT_16BIT))
            tmpval |= 4;        /* 8bit */
        if (es->fmt & ESS_FMT_STEREO)
            tmpval |= 2;        /* stereo */
    }

    /* set the wavecache control reg */
    wave_set_register(chip, es->apu[channel] << 3, tmpval);

#ifdef CONFIG_PM
    es->wc_map[channel] = tmpval;
#endif
}


static void snd_es1968_playback_setup(es1968_t *chip, esschan_t *es,
                                      snd_pcm_runtime_t *runtime)
{
    u32 pa;
    int high_apu = 0;
    int channel, apu;
    int i, size;
    unsigned long flags;
    u32 freq;

    size = es->dma_size >> es->wav_shift;

    if (es->fmt & ESS_FMT_STEREO)
        high_apu++;

    for (channel = 0; channel <= high_apu; channel++) {
        apu = es->apu[channel];

        snd_es1968_program_wavecache(chip, es, channel, es->memory->buf.addr, 0);

        /* Offset to PCMBAR */
        pa = es->memory->buf.addr;
        pa -= chip->dma.addr;
        pa >>= 1;       /* words */

        pa |= 0x00400000;       /* System RAM (Bit 22) */

        if (es->fmt & ESS_FMT_STEREO) {
            /* Enable stereo */
            if (channel)
                pa |= 0x00800000;       /* (Bit 23) */
            if (es->fmt & ESS_FMT_16BIT)
                pa >>= 1;
        }

        /* base offset of dma calcs when reading the pointer
         on this left one */
        es->base[channel] = pa & 0xFFFF;

        for (i = 0; i < 16; i++)
            apu_set_register(chip, apu, i, 0x0000);

        /* Load the buffer into the wave engine */
        apu_set_register(chip, apu, 4, ((pa >> 16) & 0xFF) << 8);
        apu_set_register(chip, apu, 5, pa & 0xFFFF);
        apu_set_register(chip, apu, 6, (pa + size) & 0xFFFF);
        /* setting loop == sample len */
        apu_set_register(chip, apu, 7, size);

        /* clear effects/env.. */
        apu_set_register(chip, apu, 8, 0x0000);
        /* set amp now to 0xd0 (?), low byte is 'amplitude dest'? */
        apu_set_register(chip, apu, 9, 0xD000);

        /* clear routing stuff */
        apu_set_register(chip, apu, 11, 0x0000);
        /* dma on, no envelopes, filter to all 1s) */
        apu_set_register(chip, apu, 0, 0x400F);

        if (es->fmt & ESS_FMT_16BIT)
            es->apu_mode[channel] = ESM_APU_16BITLINEAR;
        else
            es->apu_mode[channel] = ESM_APU_8BITLINEAR;

        if (es->fmt & ESS_FMT_STEREO) {
            /* set panning: left or right */
            /* Check: different panning. On my Canyon 3D Chipset the
             Channels are swapped. I don't know, about the output
             to the SPDif Link. Perhaps you have to change this
             and not the APU Regs 4-5. */
            apu_set_register(chip, apu, 10,
                             0x8F00 | (channel ? 0 : 0x10));
            es->apu_mode[channel] += 1; /* stereo */
        } else
            apu_set_register(chip, apu, 10, 0x8F08);
    }

    spin_lock_irqsave(&chip->reg_lock, flags);
    /* clear WP interrupts */
    outw(1, chip->io_port + 0x04);
    /* enable WP ints */
    outw(inw(chip->io_port + ESM_PORT_HOST_IRQ) | ESM_HIRQ_DSIE, chip->io_port + ESM_PORT_HOST_IRQ);
    spin_unlock_irqrestore(&chip->reg_lock, flags);

    freq = runtime->rate;
    /* set frequency */
    if (freq > 48000)
        freq = 48000;
    if (freq < 4000)
        freq = 4000;

    /* hmmm.. */
    if (!(es->fmt & ESS_FMT_16BIT) && !(es->fmt & ESS_FMT_STEREO))
        freq >>= 1;

    freq = snd_es1968_compute_rate(chip, freq);

    /* Load the frequency, turn on 6dB */
    snd_es1968_apu_set_freq(chip, es->apu[0], freq);
    snd_es1968_apu_set_freq(chip, es->apu[1], freq);
}


static void init_capture_apu(es1968_t *chip, esschan_t *es, int channel,
                             unsigned int pa, unsigned int bsize,
                             int mode, int route)
{
    int i, apu = es->apu[channel];

    es->apu_mode[channel] = mode;

    /* set the wavecache control reg */
    snd_es1968_program_wavecache(chip, es, channel, pa, 1);

    /* Offset to PCMBAR */
    pa -= chip->dma.addr;
    pa >>= 1;   /* words */

    /* base offset of dma calcs when reading the pointer
     on this left one */
    es->base[channel] = pa & 0xFFFF;
    pa |= 0x00400000;   /* bit 22 -> System RAM */

    /* Begin loading the APU */
    for (i = 0; i < 16; i++)
        apu_set_register(chip, apu, i, 0x0000);

    /* need to enable subgroups.. and we should probably
     have different groups for different /dev/dsps..  */
    apu_set_register(chip, apu, 2, 0x8);

    /* Load the buffer into the wave engine */
    apu_set_register(chip, apu, 4, ((pa >> 16) & 0xFF) << 8);
    apu_set_register(chip, apu, 5, pa & 0xFFFF);
    apu_set_register(chip, apu, 6, (pa + bsize) & 0xFFFF);
    apu_set_register(chip, apu, 7, bsize);
    /* clear effects/env.. */
    apu_set_register(chip, apu, 8, 0x00F0);
    /* amplitude now?  sure.  why not.  */
    apu_set_register(chip, apu, 9, 0x0000);
    /* set filter tune, radius, polar pan */
    apu_set_register(chip, apu, 10, 0x8F08);
    /* route input */
    apu_set_register(chip, apu, 11, route);
    /* dma on, no envelopes, filter to all 1s) */
    apu_set_register(chip, apu, 0, 0x400F);
}


static void snd_es1968_capture_setup(es1968_t *chip, esschan_t *es,
                                     snd_pcm_runtime_t *runtime)
{
    int size;
    u32 freq;
    unsigned long flags;

    size = es->dma_size >> es->wav_shift;

    /* APU assignments:
     0 = mono/left SRC
     1 = right SRC
     2 = mono/left Input Mixer
     3 = right Input Mixer
     */
    /* data seems to flow from the codec, through an apu into
     the 'mixbuf' bit of page, then through the SRC apu
     and out to the real 'buffer'.  ok.  sure.  */

    /* input mixer (left/mono) */
    /* parallel in crap, see maestro reg 0xC [8-11] */
    init_capture_apu(chip, es, 2,
                     es->mixbuf->buf.addr, ESM_MIXBUF_SIZE/4, /* in words */
                     ESM_APU_INPUTMIXER, 0x14);
    /* SRC (left/mono); get input from inputing apu */
    init_capture_apu(chip, es, 0, es->memory->buf.addr, size,
                     ESM_APU_SRCONVERTOR, es->apu[2]);
    if (es->fmt & ESS_FMT_STEREO) {
        /* input mixer (right) */
        init_capture_apu(chip, es, 3,
                         es->mixbuf->buf.addr + ESM_MIXBUF_SIZE/2,
                         ESM_MIXBUF_SIZE/4, /* in words */
                         ESM_APU_INPUTMIXER, 0x15);
        /* SRC (right) */
        init_capture_apu(chip, es, 1,
                         es->memory->buf.addr + size*2, size,
                         ESM_APU_SRCONVERTOR, es->apu[3]);
    }
    freq = runtime->rate;
    /* Sample Rate conversion APUs don't like 0x10000 for their rate */
    if (freq > 47999)
        freq = 47999;
    if (freq < 4000)
        freq = 4000;

    freq = snd_es1968_compute_rate(chip, freq);

    /* Load the frequency, turn on 6dB */
    snd_es1968_apu_set_freq(chip, es->apu[0], freq);
    snd_es1968_apu_set_freq(chip, es->apu[1], freq);

    /* fix mixer rate at 48khz.  and its _must_ be 0x10000. */
    freq = 0x10000;
    snd_es1968_apu_set_freq(chip, es->apu[2], freq);
    snd_es1968_apu_set_freq(chip, es->apu[3], freq);

    spin_lock_irqsave(&chip->reg_lock, flags);
    /* clear WP interrupts */
    outw(1, chip->io_port + 0x04);
    /* enable WP ints */
    outw(inw(chip->io_port + ESM_PORT_HOST_IRQ) | ESM_HIRQ_DSIE, chip->io_port + ESM_PORT_HOST_IRQ);
    spin_unlock_irqrestore(&chip->reg_lock, flags);
}

/*******************
 *  ALSA Interface *
 *******************/

static int snd_es1968_pcm_prepare(snd_pcm_substream_t *substream)
{
    es1968_t *chip = snd_pcm_substream_chip(substream);
    snd_pcm_runtime_t *runtime = substream->runtime;
    esschan_t *es = runtime->private_data;

    es->dma_size = snd_pcm_lib_buffer_bytes(substream);
    es->frag_size = snd_pcm_lib_period_bytes(substream);

    es->wav_shift = 1; /* maestro handles always 16bit */
    es->fmt = 0;
    if (snd_pcm_format_width(runtime->format) == 16)
        es->fmt |= ESS_FMT_16BIT;
    if (runtime->channels > 1) {
        es->fmt |= ESS_FMT_STEREO;
        if (es->fmt & ESS_FMT_16BIT) /* 8bit is already word shifted */
            es->wav_shift++;
    }
    es->bob_freq = snd_es1968_calc_bob_rate(chip, es, runtime);

    switch (es->mode) {
    case ESM_MODE_PLAY:
        snd_es1968_playback_setup(chip, es, runtime);
        break;
    case ESM_MODE_CAPTURE:
        snd_es1968_capture_setup(chip, es, runtime);
        break;
    }

    return 0;
}

static int snd_es1968_pcm_trigger(snd_pcm_substream_t *substream, int cmd)
{
    es1968_t *chip = snd_pcm_substream_chip(substream);
    esschan_t *es = substream->runtime->private_data;

    spin_lock(&chip->substream_lock);
    switch (cmd) {
    case SNDRV_PCM_TRIGGER_START:
    case SNDRV_PCM_TRIGGER_RESUME:
        if (es->running)
            break;
        snd_es1968_bob_inc(chip, es->bob_freq);
        es->count = 0;
        es->hwptr = 0;
        snd_es1968_pcm_start(chip, es);
        es->running = 1;
        break;
    case SNDRV_PCM_TRIGGER_STOP:
    case SNDRV_PCM_TRIGGER_SUSPEND:
        if (! es->running)
            break;
        snd_es1968_pcm_stop(chip, es);
        es->running = 0;
        snd_es1968_bob_dec(chip);
        break;
    }
    spin_unlock(&chip->substream_lock);
    return 0;
}

static snd_pcm_uframes_t snd_es1968_pcm_pointer(snd_pcm_substream_t *substream)
{
    es1968_t *chip = snd_pcm_substream_chip(substream);
    esschan_t *es = substream->runtime->private_data;
    unsigned int ptr;

    ptr = snd_es1968_get_dma_ptr(chip, es) << es->wav_shift;

    return bytes_to_frames(substream->runtime, ptr % es->dma_size);
}

static snd_pcm_hardware_t snd_es1968_playback = {
    /*  info:             */    (SNDRV_PCM_INFO_MMAP |
                                 SNDRV_PCM_INFO_MMAP_VALID |
                                 SNDRV_PCM_INFO_INTERLEAVED |
                                 SNDRV_PCM_INFO_BLOCK_TRANSFER |
                                 /*SNDRV_PCM_INFO_PAUSE |*/
                                 SNDRV_PCM_INFO_RESUME),
                                 /*     formats:          */    SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE,
                                 /*     rates:            */    SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000,
                                 /*     rate_min:         */    4000,
                                 /*     rate_max:         */    48000,
                                 /*     channels_min:     */    1,
                                 /*     channels_max:     */    2,
                                 /*     buffer_bytes_max: */    65536,
                                 /*     period_bytes_min: */    256,
                                 /*     period_bytes_max: */    65536,
                                 /*     periods_min:      */    1,
                                 /*     periods_max:      */    1024,
                                 /*     fifo_size:        */    0,
};

static snd_pcm_hardware_t snd_es1968_capture = {
    /*  info:             */    (SNDRV_PCM_INFO_NONINTERLEAVED |
                                 SNDRV_PCM_INFO_MMAP |
                                 SNDRV_PCM_INFO_MMAP_VALID |
                                 SNDRV_PCM_INFO_BLOCK_TRANSFER |
                                 /*SNDRV_PCM_INFO_PAUSE |*/
                                 SNDRV_PCM_INFO_RESUME),
                                 /*     formats:          */    /*SNDRV_PCM_FMTBIT_U8 |*/ SNDRV_PCM_FMTBIT_S16_LE,
                                 /*     rates:            */    SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000,
                                 /*     rate_min:         */    4000,
                                 /*     rate_max:         */    48000,
                                 /*     channels_min:     */    1,
                                 /*     channels_max:     */    2,
                                 /*     buffer_bytes_max: */    65536,
                                 /*     period_bytes_min: */    256,
                                 /*     period_bytes_max: */    65536,
                                 /*     periods_min:      */    1,
                                 /*     periods_max:      */    1024,
                                 /*     fifo_size:        */    0,
};

/* *************************
 * DMA memory management *
 *************************/

/* Because the Maestro can only take addresses relative to the PCM base address
 register :( */

static int calc_available_memory_size(es1968_t *chip)
{
    struct list_head *p;
    int max_size = 0;

    down(&chip->memory_mutex);
    list_for_each(p, &chip->buf_list) {
        esm_memory_t *buf = list_entry(p, esm_memory_t, list);
        if (buf->empty && buf->buf.bytes > max_size)
            max_size = buf->buf.bytes;
    }
    up(&chip->memory_mutex);
    if (max_size >= 128*1024)
        max_size = 127*1024;
    return max_size;
}

/* allocate a new memory chunk with the specified size */
static esm_memory_t *snd_es1968_new_memory(es1968_t *chip, int size)
{
    esm_memory_t *buf;
    struct list_head *p;

    size = ((size + ESM_MEM_ALIGN - 1) / ESM_MEM_ALIGN) * ESM_MEM_ALIGN;
    down(&chip->memory_mutex);
    list_for_each(p, &chip->buf_list) {
        buf = list_entry(p, esm_memory_t, list);
        if (buf->empty && buf->buf.bytes >= size)
            goto __found;
    }
    up(&chip->memory_mutex);
    return NULL;

__found:
    if (buf->buf.bytes > size) {
        esm_memory_t *chunk = kmalloc(sizeof(*chunk), GFP_KERNEL);
        if (chunk == NULL) {
            up(&chip->memory_mutex);
            return NULL;
        }
        chunk->buf = buf->buf;
        chunk->buf.bytes -= size;
        chunk->buf.area += size;
        chunk->buf.addr += size;
        chunk->empty = 1;
        buf->buf.bytes = size;
        list_add(&chunk->list, &buf->list);
    }
    buf->empty = 0;
    up(&chip->memory_mutex);
    return buf;
}

/* free a memory chunk */
static void snd_es1968_free_memory(es1968_t *chip, esm_memory_t *buf)
{
    esm_memory_t *chunk;

    down(&chip->memory_mutex);
    buf->empty = 1;
    if (buf->list.prev != &chip->buf_list) {
        chunk = list_entry(buf->list.prev, esm_memory_t, list);
        if (chunk->empty) {
            chunk->buf.bytes += buf->buf.bytes;
            list_del(&buf->list);
            kfree(buf);
            buf = chunk;
        }
    }
    if (buf->list.next != &chip->buf_list) {
        chunk = list_entry(buf->list.next, esm_memory_t, list);
        if (chunk->empty) {
            buf->buf.bytes += chunk->buf.bytes;
            list_del(&chunk->list);
            kfree(chunk);
        }
    }
    up(&chip->memory_mutex);
}

static void snd_es1968_free_dmabuf(es1968_t *chip)
{
    struct list_head *p;

    if (! chip->dma.area)
        return;
    snd_dma_reserve_buf(&chip->dma, snd_dma_pci_buf_id(chip->pci));
    while ((p = chip->buf_list.next) != &chip->buf_list) {
        esm_memory_t *chunk = list_entry(p, esm_memory_t, list);
        list_del(p);
        kfree(chunk);
    }
}

static int __devinit
snd_es1968_init_dmabuf(es1968_t *chip)
{
        int err;
        esm_memory_t *chunk;

        chip->dma.dev.type = SNDRV_DMA_TYPE_DEV;
        chip->dma.dev.dev = snd_dma_pci_data(chip->pci);
        if (! snd_dma_get_reserved_buf(&chip->dma, snd_dma_pci_buf_id(chip->pci))) {
                err = snd_dma_alloc_pages_fallback(SNDRV_DMA_TYPE_DEV,
                                                   snd_dma_pci_data(chip->pci),
                                                   chip->total_bufsize, &chip->dma);
                if (err < 0 || ! chip->dma.area) {
                        snd_printk("es1968: can't allocate dma pages for size %d\n",
                                   chip->total_bufsize);
                        return -ENOMEM;
                }
                if ((chip->dma.addr + chip->dma.bytes - 1) & ~((1 << 28) - 1)) {
                        snd_dma_free_pages(&chip->dma);
                        snd_printk("es1968: DMA buffer beyond 256MB.\n");
                        return -ENOMEM;
                }
        }

        INIT_LIST_HEAD(&chip->buf_list);
        /* allocate an empty chunk */
        chunk = kmalloc(sizeof(*chunk), GFP_KERNEL);
        if (chunk == NULL) {
                snd_es1968_free_dmabuf(chip);
                return -ENOMEM;
        }
        memset(chip->dma.area, 0, ESM_MEM_ALIGN);
        chunk->buf = chip->dma;
        chunk->buf.area += ESM_MEM_ALIGN;
        chunk->buf.addr += ESM_MEM_ALIGN;
        chunk->buf.bytes -= ESM_MEM_ALIGN;
        chunk->empty = 1;
        list_add(&chunk->list, &chip->buf_list);

        return 0;
}

/* setup the dma_areas */
/* buffer is extracted from the pre-allocated memory chunk */
static int snd_es1968_hw_params(snd_pcm_substream_t *substream,
                                snd_pcm_hw_params_t *hw_params)
{
    es1968_t *chip = snd_pcm_substream_chip(substream);
    snd_pcm_runtime_t *runtime = substream->runtime;
    esschan_t *chan = runtime->private_data;
    int size = params_buffer_bytes(hw_params);

    if (chan->memory) {
        if (chan->memory->buf.bytes >= size) {
            runtime->dma_bytes = size;
            return 0;
        }
        snd_es1968_free_memory(chip, chan->memory);
    }
    chan->memory = snd_es1968_new_memory(chip, size);
    if (chan->memory == NULL) {
        // snd_printd("cannot allocate dma buffer: size = %d\n", size);
        return -ENOMEM;
    }
    snd_pcm_set_runtime_buffer(substream, &chan->memory->buf);
    return 1; /* area was changed */
}

/* remove dma areas if allocated */
static int snd_es1968_hw_free(snd_pcm_substream_t * substream)
{
    es1968_t *chip = snd_pcm_substream_chip(substream);
    snd_pcm_runtime_t *runtime = substream->runtime;
    esschan_t *chan;

    if (runtime->private_data == NULL)
        return 0;
    chan = runtime->private_data;
    if (chan->memory) {
        snd_es1968_free_memory(chip, chan->memory);
        chan->memory = NULL;
    }
    return 0;
}


/*
 * allocate APU pair
 */
static int snd_es1968_alloc_apu_pair(es1968_t *chip, int type)
{
    int apu;

    for (apu = 0; apu < NR_APUS; apu += 2) {
        if (chip->apu[apu] == ESM_APU_FREE &&
            chip->apu[apu + 1] == ESM_APU_FREE) {
            chip->apu[apu] = chip->apu[apu + 1] = type;
            return apu;
        }
    }
    return -EBUSY;
}

/*
 * release APU pair
 */
static void snd_es1968_free_apu_pair(es1968_t *chip, int apu)
{
    chip->apu[apu] = chip->apu[apu + 1] = ESM_APU_FREE;
}


/******************
 * PCM open/close *
 ******************/

static int snd_es1968_playback_open(snd_pcm_substream_t *substream)
{
    es1968_t *chip = snd_pcm_substream_chip(substream);
    snd_pcm_runtime_t *runtime = substream->runtime;
    esschan_t *es;
    int apu1;

    /* search 2 APUs */
    apu1 = snd_es1968_alloc_apu_pair(chip, ESM_APU_PCM_PLAY);
    if (apu1 < 0)
        return apu1;

    es = kcalloc(1, sizeof(*es), GFP_KERNEL);
    if (!es) {
        snd_es1968_free_apu_pair(chip, apu1);
        return -ENOMEM;
    }

    es->apu[0] = apu1;
    es->apu[1] = apu1 + 1;
    es->apu_mode[0] = 0;
    es->apu_mode[1] = 0;
    es->running = 0;
    es->substream = substream;
    es->mode = ESM_MODE_PLAY;

    runtime->private_data = es;
    runtime->hw = snd_es1968_playback;
    runtime->hw.buffer_bytes_max = runtime->hw.period_bytes_max =
        calc_available_memory_size(chip);
#if 0
    snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
                               1024);
#endif
    spin_lock_irq(&chip->substream_lock);
    list_add(&es->list, &chip->substream_list);
    spin_unlock_irq(&chip->substream_lock);

    return 0;
}

static int snd_es1968_capture_open(snd_pcm_substream_t *substream)
{
    snd_pcm_runtime_t *runtime = substream->runtime;
    es1968_t *chip = snd_pcm_substream_chip(substream);
    esschan_t *es;
    int apu1, apu2;

    apu1 = snd_es1968_alloc_apu_pair(chip, ESM_APU_PCM_CAPTURE);
    if (apu1 < 0)
        return apu1;
    
    apu2 = snd_es1968_alloc_apu_pair(chip, ESM_APU_PCM_RATECONV);
    if (apu2 < 0) {
        snd_es1968_free_apu_pair(chip, apu1);
        return apu2;
    }

    es = kcalloc(1, sizeof(*es), GFP_KERNEL);
    if (!es) {
        snd_es1968_free_apu_pair(chip, apu1);
        snd_es1968_free_apu_pair(chip, apu2);
        return -ENOMEM;
    }

    es->apu[0] = apu1;
    es->apu[1] = apu1 + 1;
    es->apu[2] = apu2;
    es->apu[3] = apu2 + 1;
    es->apu_mode[0] = 0;
    es->apu_mode[1] = 0;
    es->apu_mode[2] = 0;
    es->apu_mode[3] = 0;
    es->running = 0;
    es->substream = substream;
    es->mode = ESM_MODE_CAPTURE;

    /* get mixbuffer */
    if ((es->mixbuf = snd_es1968_new_memory(chip, ESM_MIXBUF_SIZE)) == NULL) {
        snd_es1968_free_apu_pair(chip, apu1);
        snd_es1968_free_apu_pair(chip, apu2);
        kfree(es);
        return -ENOMEM;
    }
    memset(es->mixbuf->buf.area, 0, ESM_MIXBUF_SIZE);

    runtime->private_data = es;
    runtime->hw = snd_es1968_capture;
    runtime->hw.buffer_bytes_max = runtime->hw.period_bytes_max =
        calc_available_memory_size(chip) - 1024; /* keep MIXBUF size */
#if 0
    snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
                               1024);
#endif
    spin_lock_irq(&chip->substream_lock);
    list_add(&es->list, &chip->substream_list);
    spin_unlock_irq(&chip->substream_lock);

    return 0;
}

static int snd_es1968_playback_close(snd_pcm_substream_t * substream)
{
    es1968_t *chip = snd_pcm_substream_chip(substream);
    esschan_t *es;

    if (substream->runtime->private_data == NULL)
        return 0;
    es = substream->runtime->private_data;
    spin_lock_irq(&chip->substream_lock);
    list_del(&es->list);
    spin_unlock_irq(&chip->substream_lock);
    snd_es1968_free_apu_pair(chip, es->apu[0]);
    kfree(es);

    return 0;
}

static int snd_es1968_capture_close(snd_pcm_substream_t * substream)
{
    es1968_t *chip = snd_pcm_substream_chip(substream);
    esschan_t *es;

    if (substream->runtime->private_data == NULL)
        return 0;
    es = substream->runtime->private_data;
    spin_lock_irq(&chip->substream_lock);
    list_del(&es->list);
    spin_unlock_irq(&chip->substream_lock);
    snd_es1968_free_memory(chip, es->mixbuf);
    snd_es1968_free_apu_pair(chip, es->apu[0]);
    snd_es1968_free_apu_pair(chip, es->apu[2]);
    kfree(es);

    return 0;
}
static snd_pcm_ops_t snd_es1968_playback_ops = {
    /*  open:     */    snd_es1968_playback_open,
    /*  close:    */    snd_es1968_playback_close,
    /*  ioctl:    */    snd_pcm_lib_ioctl,
    /*  hw_params:*/    snd_es1968_hw_params,
    /*  hw_free:  */    snd_es1968_hw_free,
    /*  prepare:  */    snd_es1968_pcm_prepare,
    /*  trigger:  */    snd_es1968_pcm_trigger,
    /*  pointer:  */    snd_es1968_pcm_pointer,
    0,0
};

static snd_pcm_ops_t snd_es1968_capture_ops = {
    /*  open:     */    snd_es1968_capture_open,
    /*  close:    */    snd_es1968_capture_close,
    /*  ioctl:    */    snd_pcm_lib_ioctl,
    /*  hw_params:*/    snd_es1968_hw_params,
    /*  hw_free:  */    snd_es1968_hw_free,
    /*  prepare:  */    snd_es1968_pcm_prepare,
    /*  trigger:  */    snd_es1968_pcm_trigger,
    /*  pointer:  */    snd_es1968_pcm_pointer,
    /*  copy:     */    0,
    0
};


/*
 * measure clock
 */
#define CLOCK_MEASURE_BUFSIZE   16768   /* enough large for a single shot */

static void __devinit es1968_measure_clock(es1968_t *chip)
{
    int i, apu;
    unsigned int pa, offset, t;
    esm_memory_t *memory;
    struct timeval start_time, stop_time;

    if (chip->clock == 0)
        chip->clock = 48000; /* default clock value */

    /* search 2 APUs (although one apu is enough) */
    if ((apu = snd_es1968_alloc_apu_pair(chip, ESM_APU_PCM_PLAY)) < 0) {
        snd_printk("Hmm, cannot find empty APU pair!?\n");
        return;
    }
    if ((memory = snd_es1968_new_memory(chip, CLOCK_MEASURE_BUFSIZE)) == NULL) {
        snd_printk("cannot allocate dma buffer - using default clock %d\n", chip->clock);
        snd_es1968_free_apu_pair(chip, apu);
        return;
    }

    memset(memory->buf.area, 0, CLOCK_MEASURE_BUFSIZE);

    wave_set_register(chip, apu << 3, (memory->buf.addr - 0x10) & 0xfff8);

    pa = (unsigned int)((memory->buf.addr - chip->dma.addr) >> 1);
    pa |= 0x00400000;   /* System RAM (Bit 22) */

    /* initialize apu */
    for (i = 0; i < 16; i++)
        apu_set_register(chip, apu, i, 0x0000);

    apu_set_register(chip, apu, 0, 0x400f);
    apu_set_register(chip, apu, 4, ((pa >> 16) & 0xff) << 8);
    apu_set_register(chip, apu, 5, pa & 0xffff);
    apu_set_register(chip, apu, 6, (pa + CLOCK_MEASURE_BUFSIZE/2) & 0xffff);
    apu_set_register(chip, apu, 7, CLOCK_MEASURE_BUFSIZE/2);
    apu_set_register(chip, apu, 8, 0x0000);
    apu_set_register(chip, apu, 9, 0xD000);
    apu_set_register(chip, apu, 10, 0x8F08);
    apu_set_register(chip, apu, 11, 0x0000);
    spin_lock_irq(&chip->reg_lock);
    outw(1, chip->io_port + 0x04); /* clear WP interrupts */
    outw(inw(chip->io_port + ESM_PORT_HOST_IRQ) | ESM_HIRQ_DSIE, chip->io_port + ESM_PORT_HOST_IRQ); /* enable WP ints */
    spin_unlock_irq(&chip->reg_lock);

    snd_es1968_apu_set_freq(chip, apu, ((unsigned int)48000 << 16) / chip->clock); /* 48000 Hz */

    chip->in_measurement = 1;
    chip->measure_apu = apu;
    spin_lock_irq(&chip->reg_lock);
    snd_es1968_bob_inc(chip, ESM_BOB_FREQ);
    __apu_set_register(chip, apu, 5, pa & 0xffff);
    snd_es1968_trigger_apu(chip, apu, ESM_APU_16BITLINEAR);
    do_gettimeofday(&start_time);
    spin_unlock_irq(&chip->reg_lock);
    msleep(50);
    spin_lock_irq(&chip->reg_lock);
    offset = __apu_get_register(chip, apu, 5);
    do_gettimeofday(&stop_time);
    snd_es1968_trigger_apu(chip, apu, 0); /* stop */
    snd_es1968_bob_dec(chip);
    chip->in_measurement = 0;
    spin_unlock_irq(&chip->reg_lock);

    /* check the current position */
    offset -= (pa & 0xffff);
    offset &= 0xfffe;
    offset += chip->measure_count * (CLOCK_MEASURE_BUFSIZE/2);
#if 0 /* vladest patch baseg on r.ihle suggestion */
    t = stop_time.tv_sec - start_time.tv_sec;
    t *= 1000000;
    if (stop_time.tv_usec < start_time.tv_usec)
        t -= start_time.tv_usec - stop_time.tv_usec;
    else
        t += stop_time.tv_usec - start_time.tv_usec;
#else
    t = 50000;
#endif
    if (t == 0) {
        snd_printk("?? calculation error..\n");
    } else {
        offset *= 1000;
        offset = (offset / t) * 1000 + ((offset % t) * 1000) / t;
        if (offset < 47500 || offset > 48500) {
            if (offset >= 40000 && offset <= 50000)
                chip->clock = (chip->clock * offset) / 48000;
        }
        printk(KERN_INFO "es1968: clocking to %d\n", chip->clock);
    }
    snd_es1968_free_memory(chip, memory);
    snd_es1968_free_apu_pair(chip, apu);
}


/*
 */
static void snd_es1968_pcm_free(snd_pcm_t *pcm)
{
    es1968_t *esm = pcm->private_data;
    snd_es1968_free_dmabuf(esm);
    esm->pcm = NULL;
}

static int __devinit
snd_es1968_pcm(es1968_t *chip, int device)
{
    snd_pcm_t *pcm;
    int err;

    /* get DMA buffer */
    if ((err = snd_es1968_init_dmabuf(chip)) < 0)
        return err;

    /* set PCMBAR */
    wave_set_register(chip, 0x01FC, chip->dma.addr >> 12);
    wave_set_register(chip, 0x01FD, chip->dma.addr >> 12);
    wave_set_register(chip, 0x01FE, chip->dma.addr >> 12);
    wave_set_register(chip, 0x01FF, chip->dma.addr >> 12);

    if ((err = snd_pcm_new(chip->card, "ESS Maestro", device,
                           chip->playback_streams,
                           chip->capture_streams, &pcm)) < 0)
        return err;

    pcm->private_data = chip;
    pcm->private_free = snd_es1968_pcm_free;

    snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_es1968_playback_ops);
    snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_es1968_capture_ops);

    pcm->info_flags = 0;

    strcpy(pcm->name, "ESS Maestro");

    chip->pcm = pcm;

    return 0;
}

/*
 * update pointer
 */
static void snd_es1968_update_pcm(es1968_t *chip, esschan_t *es)
{
    unsigned int hwptr;
    unsigned int diff;
    snd_pcm_substream_t *subs = es->substream;

    if (subs == NULL || !es->running)
        return;

    hwptr = snd_es1968_get_dma_ptr(chip, es) << es->wav_shift;
    hwptr %= es->dma_size;

    diff = (es->dma_size + hwptr - es->hwptr) % es->dma_size;

    es->hwptr = hwptr;
    es->count += diff;

    if (es->count > es->frag_size) {
        spin_unlock(&chip->substream_lock);
        snd_pcm_period_elapsed(subs);
        spin_lock(&chip->substream_lock);
        es->count %= es->frag_size;
    }
}

/*
 */
static void es1968_update_hw_volume(unsigned long private_data)
{
    es1968_t *chip = (es1968_t *) private_data;
    int x, val;
    unsigned long flags;

    /* Figure out which volume control button was pushed,
     based on differences from the default register
     values. */
    x = inb(chip->io_port + 0x1c);
    /* Reset the volume control registers. */
    outb(0x88, chip->io_port + 0x1c);
    outb(0x88, chip->io_port + 0x1d);
    outb(0x88, chip->io_port + 0x1e);
    outb(0x88, chip->io_port + 0x1f);

    if (chip->in_suspend)
        return;

    if (! chip->master_switch || ! chip->master_volume)
        return;

    /* FIXME: we can't call snd_ac97_* functions since here is in tasklet. */
    spin_lock_irqsave(&chip->ac97_lock, flags);
    val = chip->ac97->regs[AC97_MASTER];
    if (x & 1) {
        /* mute */
        val ^= 0x8000;
        chip->ac97->regs[AC97_MASTER] = val;
        outw(val, chip->io_port + ESM_AC97_DATA);
        outb(AC97_MASTER, chip->io_port + ESM_AC97_INDEX);
        snd_ctl_notify(chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
                       &chip->master_switch->id);
    } else {
        val &= 0x7fff;
        if (((x>>1) & 7) > 4) {
            /* volume up */
            if ((val & 0xff) > 0)
                val--;
            if ((val & 0xff00) > 0)
                val -= 0x0100;
        } else {
            /* volume down */
            if ((val & 0xff) < 0x1f)
                val++;
            if ((val & 0xff00) < 0x1f00)
                val += 0x0100;
        }
        chip->ac97->regs[AC97_MASTER] = val;
        outw(val, chip->io_port + ESM_AC97_DATA);
        outb(AC97_MASTER, chip->io_port + ESM_AC97_INDEX);
        snd_ctl_notify(chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
                       &chip->master_volume->id);
    }
    spin_unlock_irqrestore(&chip->ac97_lock, flags);
}

/*
 * interrupt handler
 */
static irqreturn_t snd_es1968_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
    es1968_t *chip = dev_id;
    u32 event;
#ifdef TARGET_OS2
    int fOurIrq = FALSE;
#endif

    if (!(event = inb(chip->io_port + 0x1A)))
        return IRQ_NONE;

#ifdef TARGET_OS2
    fOurIrq = TRUE;
#endif
    outw(inw(chip->io_port + 4) & 1, chip->io_port + 4);

    if (event & ESM_HWVOL_IRQ)
        tasklet_hi_schedule(&chip->hwvol_tq); /* we'll do this later */

    /* else ack 'em all, i imagine */
    outb(0xFF, chip->io_port + 0x1A);

    if ((event & ESM_MPU401_IRQ) && chip->rmidi) {
        snd_mpu401_uart_interrupt(irq, chip->rmidi->private_data, regs);
    }

    if (event & ESM_SOUND_IRQ) {
        struct list_head *p;
        spin_lock(&chip->substream_lock);
        list_for_each(p, &chip->substream_list) {
            esschan_t *es = list_entry(p, esschan_t, list);
            if (es->running)
                snd_es1968_update_pcm(chip, es);
        }
        spin_unlock(&chip->substream_lock);
        if (chip->in_measurement) {
            unsigned int curp = __apu_get_register(chip, chip->measure_apu, 5);
            if (curp < chip->measure_lastpos)
                chip->measure_count++;
            chip->measure_lastpos = curp;
        }
    }

#ifdef TARGET_OS2
    if (fOurIrq) {
        eoi_irq(irq);
    }
#endif //TARGET_OS2
    return IRQ_HANDLED;
}

/*
 *  Mixer stuff
 */

static int __devinit
snd_es1968_mixer(es1968_t *chip)
{
    ac97_bus_t *pbus;
    ac97_template_t ac97;
    snd_ctl_elem_id_t id;
    int err;
    static ac97_bus_ops_t ops = {
        0, 0, snd_es1968_ac97_write,
        snd_es1968_ac97_read,0,0
    };

    if ((err = snd_ac97_bus(chip->card, 0, &ops, NULL, &pbus)) < 0)
        return err;
    pbus->no_vra = 1; /* ES1968 doesn't need VRA */

    memset(&ac97, 0, sizeof(ac97));
    ac97.private_data = chip;
    if ((err = snd_ac97_mixer(pbus, &ac97, &chip->ac97)) < 0)
        return err;
    
    /* attach master switch / volumes for h/w volume control */
    memset(&id, 0, sizeof(id));
    id.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
    strcpy(id.name, "Master Playback Switch");
    chip->master_switch = snd_ctl_find_id(chip->card, &id);
    memset(&id, 0, sizeof(id));
    id.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
    strcpy(id.name, "Master Playback Volume");
    chip->master_volume = snd_ctl_find_id(chip->card, &id);

    return 0;
}

/*
 * reset ac97 codec
 */

static void snd_es1968_ac97_reset(es1968_t *chip)
{
    unsigned long ioaddr = chip->io_port;

    unsigned short save_ringbus_a;
    unsigned short save_68;
    unsigned short w;
    unsigned int vend;

    /* save configuration */
    save_ringbus_a = inw(ioaddr + 0x36);

    //outw(inw(ioaddr + 0x38) & 0xfffc, ioaddr + 0x38); /* clear second codec id? */
    /* set command/status address i/o to 1st codec */
    outw(inw(ioaddr + 0x3a) & 0xfffc, ioaddr + 0x3a);
    outw(inw(ioaddr + 0x3c) & 0xfffc, ioaddr + 0x3c);

    /* disable ac link */
    outw(0x0000, ioaddr + 0x36);
    save_68 = inw(ioaddr + 0x68);
    pci_read_config_word(chip->pci, 0x58, &w);  /* something magical with gpio and bus arb. */
    pci_read_config_dword(chip->pci, PCI_SUBSYSTEM_VENDOR_ID, &vend);
    if (w & 1)
        save_68 |= 0x10;
    outw(0xfffe, ioaddr + 0x64);        /* unmask gpio 0 */
    outw(0x0001, ioaddr + 0x68);        /* gpio write */
    outw(0x0000, ioaddr + 0x60);        /* write 0 to gpio 0 */
    udelay(20);
    outw(0x0001, ioaddr + 0x60);        /* write 1 to gpio 1 */
    msleep(20);

    outw(save_68 | 0x1, ioaddr + 0x68); /* now restore .. */
    outw((inw(ioaddr + 0x38) & 0xfffc) | 0x1, ioaddr + 0x38);
    outw((inw(ioaddr + 0x3a) & 0xfffc) | 0x1, ioaddr + 0x3a);
    outw((inw(ioaddr + 0x3c) & 0xfffc) | 0x1, ioaddr + 0x3c);

    /* now the second codec */
    /* disable ac link */
    outw(0x0000, ioaddr + 0x36);
    outw(0xfff7, ioaddr + 0x64);        /* unmask gpio 3 */
    save_68 = inw(ioaddr + 0x68);
    outw(0x0009, ioaddr + 0x68);        /* gpio write 0 & 3 ?? */
    outw(0x0001, ioaddr + 0x60);        /* write 1 to gpio */
    udelay(20);
    outw(0x0009, ioaddr + 0x60);        /* write 9 to gpio */
    msleep(500);
    //outw(inw(ioaddr + 0x38) & 0xfffc, ioaddr + 0x38);
    outw(inw(ioaddr + 0x3a) & 0xfffc, ioaddr + 0x3a);
    outw(inw(ioaddr + 0x3c) & 0xfffc, ioaddr + 0x3c);

#if 0                           /* the loop here needs to be much better if we want it.. */
    snd_printk("trying software reset\n");
    /* try and do a software reset */
    outb(0x80 | 0x7c, ioaddr + 0x30);
    for (w = 0;; w++) {
        if ((inw(ioaddr + 0x30) & 1) == 0) {
            if (inb(ioaddr + 0x32) != 0)
                break;

            outb(0x80 | 0x7d, ioaddr + 0x30);
            if (((inw(ioaddr + 0x30) & 1) == 0)
                && (inb(ioaddr + 0x32) != 0))
                break;
            outb(0x80 | 0x7f, ioaddr + 0x30);
            if (((inw(ioaddr + 0x30) & 1) == 0)
                && (inb(ioaddr + 0x32) != 0))
                break;
        }

        if (w > 10000) {
            outb(inb(ioaddr + 0x37) | 0x08, ioaddr + 0x37);     /* do a software reset */
            msleep(500);        /* oh my.. */
            outb(inb(ioaddr + 0x37) & ~0x08,
                 ioaddr + 0x37);
            udelay(1);
            outw(0x80, ioaddr + 0x30);
            for (w = 0; w < 10000; w++) {
                if ((inw(ioaddr + 0x30) & 1) == 0)
                    break;
            }
        }
    }
#endif
    if (vend == NEC_VERSA_SUBID1 || vend == NEC_VERSA_SUBID2) {
        /* turn on external amp? */
        outw(0xf9ff, ioaddr + 0x64);
        outw(inw(ioaddr + 0x68) | 0x600, ioaddr + 0x68);
        outw(0x0209, ioaddr + 0x60);
    }

    /* restore.. */
    outw(save_ringbus_a, ioaddr + 0x36);

    /* Turn on the 978 docking chip.
     First frob the "master output enable" bit,
     then set most of the playback volume control registers to max. */
    outb(inb(ioaddr+0xc0)|(1<<5), ioaddr+0xc0);
    outb(0xff, ioaddr+0xc3);
    outb(0xff, ioaddr+0xc4);
    outb(0xff, ioaddr+0xc6);
    outb(0xff, ioaddr+0xc8);
    outb(0x3f, ioaddr+0xcf);
    outb(0x3f, ioaddr+0xd0);
}

static void snd_es1968_reset(es1968_t *chip)
{
    /* Reset */
    outw(ESM_RESET_MAESTRO | ESM_RESET_DIRECTSOUND,
         chip->io_port + ESM_PORT_HOST_IRQ);
    udelay(10);
    outw(0x0000, chip->io_port + ESM_PORT_HOST_IRQ);
    udelay(10);
}

/*
 * power management
 */
static void snd_es1968_set_acpi(es1968_t *chip, int state)
{
    u16 active_mask = acpi_state_mask[state];

    pci_set_power_state(chip->pci, state);
    /* make sure the units we care about are on
     XXX we might want to do this before state flipping? */
    pci_write_config_word(chip->pci, 0x54, ~ active_mask);
    pci_write_config_word(chip->pci, 0x56, ~ active_mask);
}


/*
 * initialize maestro chip
 */
static void snd_es1968_chip_init(es1968_t *chip)
{
    struct pci_dev *pci = chip->pci;
    int i;
    unsigned long iobase  = chip->io_port;
    u16 w;
    u32 n;

    /* We used to muck around with pci config space that
     * we had no business messing with.  We don't know enough
     * about the machine to know which DMA mode is appropriate,
     * etc.  We were guessing wrong on some machines and making
     * them unhappy.  We now trust in the BIOS to do things right,
     * which almost certainly means a new host of problems will
     * arise with broken BIOS implementations.  screw 'em.
     * We're already intolerant of machines that don't assign
     * IRQs.
     */

    /* do config work at full power */
    snd_es1968_set_acpi(chip, ACPI_D0);

    /* Config Reg A */
    pci_read_config_word(pci, ESM_CONFIG_A, &w);

    /*      Use TDMA for now. TDMA works on all boards, so while its
     *      not the most efficient its the simplest. */
    w &= ~DMA_CLEAR;    /* Clear DMA bits */
    w |= DMA_TDMA;              /* TDMA on */
    w &= ~(PIC_SNOOP1 | PIC_SNOOP2);    /* Clear Pic Snoop Mode Bits */
    w &= ~SAFEGUARD;    /* Safeguard off */
    w |= POST_WRITE;    /* Posted write */
    w |= ISA_TIMING;    /* ISA timing on */
    /* XXX huh?  claims to be reserved.. */
    w &= ~SWAP_LR;              /* swap left/right
    seems to only have effect on SB
    Emulation */
    w &= ~SUBTR_DECODE; /* Subtractive decode off */

    pci_write_config_word(pci, ESM_CONFIG_A, w);

    /* Config Reg B */

    pci_read_config_word(pci, ESM_CONFIG_B, &w);

    w &= ~(1 << 15);    /* Turn off internal clock multiplier */
    /* XXX how do we know which to use? */
    w &= ~(1 << 14);    /* External clock */

    w &= ~SPDIF_CONFB;  /* disable S/PDIF output */
    w |= HWV_CONFB;             /* HWV on */
    w |= DEBOUNCE;              /* Debounce off: easier to push the HW buttons */
    w &= ~GPIO_CONFB;   /* GPIO 4:5 */
    w |= CHI_CONFB;             /* Disconnect from the CHI.  Enabling this made a dell 7500 work. */
    w &= ~IDMA_CONFB;   /* IDMA off (undocumented) */
    w &= ~MIDI_FIX;             /* MIDI fix off (undoc) */
    w &= ~(1 << 1);             /* reserved, always write 0 */
    w &= ~IRQ_TO_ISA;   /* IRQ to ISA off (undoc) */

    pci_write_config_word(pci, ESM_CONFIG_B, w);

    /* DDMA off */

    pci_read_config_word(pci, ESM_DDMA, &w);
    w &= ~(1 << 0);
    pci_write_config_word(pci, ESM_DDMA, w);

    /*
     *  Legacy mode
     */

    pci_read_config_word(pci, ESM_LEGACY_AUDIO_CONTROL, &w);

    w &= ~ESS_ENABLE_AUDIO;     /* Disable Legacy Audio */
    w &= ~ESS_ENABLE_SERIAL_IRQ;        /* Disable SIRQ */
    w &= ~(0x1f);               /* disable mpu irq/io, game port, fm, SB */

    pci_write_config_word(pci, ESM_LEGACY_AUDIO_CONTROL, w);

    /* Set up 978 docking control chip. */
    pci_read_config_word(pci, 0x58, &w);
    w|=1<<2;    /* Enable 978. */
    w|=1<<3;    /* Turn on 978 hardware volume control. */
    w&=~(1<<11);        /* Turn on 978 mixer volume control. */
    pci_write_config_word(pci, 0x58, w);

    /* Sound Reset */

    snd_es1968_reset(chip);

    /*
     *  Ring Bus Setup
     */

    /* setup usual 0x34 stuff.. 0x36 may be chip specific */
    outw(0xC090, iobase + ESM_RING_BUS_DEST); /* direct sound, stereo */
    udelay(20);
    outw(0x3000, iobase + ESM_RING_BUS_CONTR_A); /* enable ringbus/serial */
    udelay(20);

    /*
     *  Reset the CODEC
     */

    snd_es1968_ac97_reset(chip);

    /* Ring Bus Control B */

    n = inl(iobase + ESM_RING_BUS_CONTR_B);
    n &= ~RINGB_EN_SPDIF;       /* SPDIF off */
    //w |= RINGB_EN_2CODEC;     /* enable 2nd codec */
    outl(n, iobase + ESM_RING_BUS_CONTR_B);

    /* Set hardware volume control registers to midpoints.
     We can tell which button was pushed based on how they change. */
    outb(0x88, iobase+0x1c);
    outb(0x88, iobase+0x1d);
    outb(0x88, iobase+0x1e);
    outb(0x88, iobase+0x1f);

    /* it appears some maestros (dell 7500) only work if these are set,
     regardless of wether we use the assp or not. */

    outb(0, iobase + ASSP_CONTROL_B);
    outb(3, iobase + ASSP_CONTROL_A);   /* M: Reserved bits... */
    outb(0, iobase + ASSP_CONTROL_C);   /* M: Disable ASSP, ASSP IRQ's and FM Port */

    /*
     * set up wavecache
     */
    for (i = 0; i < 16; i++) {
        /* Write 0 into the buffer area 0x1E0->1EF */
        outw(0x01E0 + i, iobase + WC_INDEX);
        outw(0x0000, iobase + WC_DATA);

        /* The 1.10 test program seem to write 0 into the buffer area
         * 0x1D0-0x1DF too.*/
        outw(0x01D0 + i, iobase + WC_INDEX);
        outw(0x0000, iobase + WC_DATA);
    }
    wave_set_register(chip, IDR7_WAVE_ROMRAM,
                      (wave_get_register(chip, IDR7_WAVE_ROMRAM) & 0xFF00));
    wave_set_register(chip, IDR7_WAVE_ROMRAM,
                      wave_get_register(chip, IDR7_WAVE_ROMRAM) | 0x100);
    wave_set_register(chip, IDR7_WAVE_ROMRAM,
                      wave_get_register(chip, IDR7_WAVE_ROMRAM) & ~0x200);
    wave_set_register(chip, IDR7_WAVE_ROMRAM,
                      wave_get_register(chip, IDR7_WAVE_ROMRAM) | ~0x400);


    maestro_write(chip, IDR2_CRAM_DATA, 0x0000);
    /* Now back to the DirectSound stuff */
    /* audio serial configuration.. ? */
    maestro_write(chip, 0x08, 0xB004);
    maestro_write(chip, 0x09, 0x001B);
    maestro_write(chip, 0x0A, 0x8000);
    maestro_write(chip, 0x0B, 0x3F37);
    maestro_write(chip, 0x0C, 0x0098);

    /* parallel in, has something to do with recording :) */
    maestro_write(chip, 0x0C,
                  (maestro_read(chip, 0x0C) & ~0xF000) | 0x8000);
    /* parallel out */
    maestro_write(chip, 0x0C,
                  (maestro_read(chip, 0x0C) & ~0x0F00) | 0x0500);

    maestro_write(chip, 0x0D, 0x7632);

    /* Wave cache control on - test off, sg off,
     enable, enable extra chans 1Mb */

    w = inw(iobase + WC_CONTROL);

    w &= ~0xFA00;               /* Seems to be reserved? I don't know */
    w |= 0xA000;                /* reserved... I don't know */
    w &= ~0x0200;               /* Channels 56,57,58,59 as Extra Play,Rec Channel enable
    Seems to crash the Computer if enabled... */
    w |= 0x0100;                /* Wave Cache Operation Enabled */
    w |= 0x0080;                /* Channels 60/61 as Placback/Record enabled */
    w &= ~0x0060;               /* Clear Wavtable Size */
    w |= 0x0020;                /* Wavetable Size : 1MB */
    /* Bit 4 is reserved */
    w &= ~0x000C;               /* DMA Stuff? I don't understand what the datasheet means */
    /* Bit 1 is reserved */
    w &= ~0x0001;               /* Test Mode off */

    outw(w, iobase + WC_CONTROL);

    /* Now clear the APU control ram */
    for (i = 0; i < NR_APUS; i++) {
        for (w = 0; w < NR_APU_REGS; w++)
            apu_set_register(chip, i, w, 0);

    }
}

/* Enable IRQ's */
static void snd_es1968_start_irq(es1968_t *chip)
{
    unsigned short w;
    w = ESM_HIRQ_DSIE | ESM_HIRQ_HW_VOLUME;
    if (chip->rmidi)
        w |= ESM_HIRQ_MPU401;
    outw(w, chip->io_port + ESM_PORT_HOST_IRQ);
}

#ifdef CONFIG_PM
/*
 * PM support
 */
static int es1968_suspend(snd_card_t *card, unsigned int state)
{
    es1968_t *chip = card->pm_private_data;

    if (! chip->do_pm)
        return 0;

    chip->in_suspend = 1;
    snd_pcm_suspend_all(chip->pcm);
    snd_ac97_suspend(chip->ac97);
    snd_es1968_bob_stop(chip);
    snd_es1968_set_acpi(chip, ACPI_D3);
    return 0;
}

static int es1968_resume(snd_card_t *card, unsigned int state)
{
    es1968_t *chip = card->pm_private_data;
    struct list_head *p;

    if (! chip->do_pm)
        return 0;

    /* restore all our config */
    pci_enable_device(chip->pci);
    pci_set_master(chip->pci);
    snd_es1968_chip_init(chip);

    /* need to restore the base pointers.. */
    if (chip->dma.addr) {
        /* set PCMBAR */
        wave_set_register(chip, 0x01FC, chip->dma.addr >> 12);
        // by vladest
        //            wave_set_register(chip, 0x01FD, chip->dma.addr >> 12);
        //            wave_set_register(chip, 0x01FE, chip->dma.addr >> 12);
        //            wave_set_register(chip, 0x01FF, chip->dma.addr >> 12);
        // !by vladest

    }

    snd_es1968_start_irq(chip);

    // by vladest 06.10.2003 16:22
    //        es1968_measure_clock(chip);
    //! by vladest

    /* restore ac97 state */
    snd_ac97_resume(chip->ac97);

    list_for_each(p, &chip->substream_list) {
        esschan_t *es = list_entry(p, esschan_t, list);
        switch (es->mode) {
        case ESM_MODE_PLAY:
            snd_es1968_playback_setup(chip, es, es->substream->runtime);
            break;
        case ESM_MODE_CAPTURE:
            snd_es1968_capture_setup(chip, es, es->substream->runtime);
            break;
        }
    }
    /* start timer again */
    if (chip->bobclient)
        snd_es1968_bob_start(chip);

    chip->in_suspend = 0;
    return 0;
}

#endif /* CONFIG_PM */

static int snd_es1968_free(es1968_t *chip)
{
    if (chip->io_port) {
        synchronize_irq(chip->irq);
        outw(1, chip->io_port + 0x04); /* clear WP interrupts */
        outw(0, chip->io_port + ESM_PORT_HOST_IRQ); /* disable IRQ */
    }
    if (chip->irq >= 0)
        free_irq(chip->irq, (void *)chip);
    snd_es1968_set_acpi(chip, ACPI_D3);
    chip->master_switch = NULL;
    chip->master_volume = NULL;
    pci_release_regions(chip->pci);
    kfree(chip);
    return 0;
}

static int snd_es1968_dev_free(snd_device_t *device)
{
    es1968_t *chip = device->device_data;
    return snd_es1968_free(chip);
}

struct ess_device_list {
    unsigned short type;        /* chip type */
    unsigned short vendor;      /* subsystem vendor id */
};

static struct ess_device_list pm_whitelist[] __devinitdata = {
    { TYPE_MAESTRO2E, 0x0e11 },     /* Compaq Armada */
    { TYPE_MAESTRO2E, 0x1028 },
    { TYPE_MAESTRO2E, 0x103c },
    { TYPE_MAESTRO2E, 0x1179 },
    { TYPE_MAESTRO2E, 0x14c0 }, /* HP omnibook 4150 */
    { TYPE_MAESTRO2E, 0x1558 },
};

static struct ess_device_list mpu_blacklist[] __devinitdata = {
    { TYPE_MAESTRO2, 0x125d },
};

static int __devinit snd_es1968_create(snd_card_t * card,
                                       struct pci_dev *pci,
                                       int total_bufsize,
                                       int play_streams,
                                       int capt_streams,
                                       int chip_type,
                                       int do_pm,
                                       es1968_t **chip_ret)
{
#ifdef TARGET_OS2
    static snd_device_ops_t ops = {
        snd_es1968_dev_free,0,0,0
    };
#else
    static snd_device_ops_t ops = {
    dev_free:       snd_es1968_dev_free,
    };
#endif
    es1968_t *chip;
    int i, err;

    *chip_ret = NULL;

    /* enable PCI device */
    if ((err = pci_enable_device(pci)) < 0)
        return err;
    /* check, if we can restrict PCI DMA transfers to 28 bits */
    if (!pci_dma_supported(pci, 0x0fffffff)) {
        snd_printk("architecture does not support 28bit PCI busmaster DMA\n");
        return -ENXIO;
    }
    pci_set_consistent_dma_mask(pci, 0x0fffffff);

    chip = kcalloc(1, sizeof(*chip), GFP_KERNEL);
    if (! chip)
        return -ENOMEM;

    /* Set Vars */
    chip->type = chip_type;
    spin_lock_init(&chip->reg_lock);
    spin_lock_init(&chip->substream_lock);
    INIT_LIST_HEAD(&chip->buf_list);
    INIT_LIST_HEAD(&chip->substream_list);
    spin_lock_init(&chip->ac97_lock);
    init_MUTEX(&chip->memory_mutex);
    tasklet_init(&chip->hwvol_tq, es1968_update_hw_volume, (unsigned long)chip);
    chip->card = card;
    chip->pci = pci;
    chip->irq = -1;
    chip->total_bufsize = total_bufsize;        /* in bytes */
    chip->playback_streams = play_streams;
    chip->capture_streams = capt_streams;

    if ((err = pci_request_regions(pci, "ESS Maestro")) < 0) {
        kfree(chip);
        return err;
    }
    chip->io_port = pci_resource_start(pci, 0);
    if (request_irq(pci->irq, snd_es1968_interrupt, SA_INTERRUPT|SA_SHIRQ,
                    "ESS Maestro", (void*)chip)) {
        snd_printk("unable to grab IRQ %d\n", pci->irq);
        snd_es1968_free(chip);
        return -EBUSY;
    }
    chip->irq = pci->irq;

    /* Clear Maestro_map */
    for (i = 0; i < 32; i++)
        chip->maestro_map[i] = 0;

    /* Clear Apu Map */
    for (i = 0; i < NR_APUS; i++)
        chip->apu[i] = ESM_APU_FREE;

    /* just to be sure */
    pci_set_master(pci);

    if (do_pm > 1) {
        /* disable power-management if not on the whitelist */
        unsigned short vend;
        pci_read_config_word(chip->pci, PCI_SUBSYSTEM_VENDOR_ID, &vend);
        for (i = 0; i < (int)ARRAY_SIZE(pm_whitelist); i++) {
            if (chip->type == pm_whitelist[i].type &&
                vend == pm_whitelist[i].vendor) {
                do_pm = 1;
                break;
            }
        }
        if (do_pm > 1) {
            /* not matched; disabling pm */
            printk(KERN_INFO "es1968: not attempting power management.\n");
            do_pm = 0;
        }
    }
    chip->do_pm = do_pm;

    snd_es1968_chip_init(chip);

    if (chip->do_pm)
        snd_card_set_pm_callback(card, es1968_suspend, es1968_resume, chip);

    if ((err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops)) < 0) {
        snd_es1968_free(chip);
        return err;
    }

    *chip_ret = chip;

    return 0;
}


/*
 * joystick
 */

static int snd_es1968_joystick_info(snd_kcontrol_t *kcontrol, snd_ctl_elem_info_t *uinfo)
{
    uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
    uinfo->count = 1;
    uinfo->value.integer.min = 0;
    uinfo->value.integer.max = 1;
    return 0;
}

static int snd_es1968_joystick_get(snd_kcontrol_t *kcontrol, snd_ctl_elem_value_t *ucontrol)
{
    es1968_t *chip = snd_kcontrol_chip(kcontrol);
    u16 val;

    pci_read_config_word(chip->pci, ESM_LEGACY_AUDIO_CONTROL, &val);
    ucontrol->value.integer.value[0] = (val & 0x04) ? 1 : 0;
    return 0;
}

static int snd_es1968_joystick_put(snd_kcontrol_t *kcontrol, snd_ctl_elem_value_t *ucontrol)
{
    es1968_t *chip = snd_kcontrol_chip(kcontrol);
    u16 val, oval;

    pci_read_config_word(chip->pci, ESM_LEGACY_AUDIO_CONTROL, &oval);
    val = oval & ~0x04;
    if (ucontrol->value.integer.value[0])
        val |= 0x04;
    if (val != oval) {
        pci_write_config_word(chip->pci, ESM_LEGACY_AUDIO_CONTROL, val);
        return 1;
    }
    return 0;
}

#define num_controls(ary) (sizeof(ary) / sizeof(snd_kcontrol_new_t))

static snd_kcontrol_new_t snd_es1968_control_switches[] __devinitdata = {
    {
        /* .iface = */SNDRV_CTL_ELEM_IFACE_CARD,0,0,
        /* .name =  */"Joystick",0,0,0,
        /* .info =  */snd_es1968_joystick_info,
        /* .get =   */snd_es1968_joystick_get,
        /* .put =   */snd_es1968_joystick_put,
    }
};

/*
 */
static int __devinit snd_es1968_probe(struct pci_dev *pci,
                                      const struct pci_device_id *pci_id)
{
    static int dev;
    snd_card_t *card;
    es1968_t *chip;
    unsigned int i;
    int err;

    printk("snd_es1968_probe cp1\n");
    if (dev >= SNDRV_CARDS)
        return -ENODEV;
    if (!enable[dev]) {
        dev++;
        return -ENOENT;
    }

    printk("snd_es1968_probe cp2\n");
    card = snd_card_new(index[dev], id[dev], THIS_MODULE, 0);
    if (!card)
        return -ENOMEM;

    printk("snd_es1968_probe cp3\n");

    if (total_bufsize[dev] < 128)
        total_bufsize[dev] = 128;
    if (total_bufsize[dev] > 4096)
        total_bufsize[dev] = 4096;
    if ((err = snd_es1968_create(card, pci,
                                 total_bufsize[dev] * 1024, /* in bytes */
                                 pcm_substreams_p[dev],
                                 pcm_substreams_c[dev],
                                 pci_id->driver_data,
                                 use_pm[dev],
                                 &chip)) < 0) {
        snd_card_free(card);
        return err;
    }

    printk("snd_es1968_probe cp4n");

    switch (chip->type) {
    case TYPE_MAESTRO2E:
        strcpy(card->driver, "ES1978");
        strcpy(card->shortname, "ESS ES1978 (Maestro 2E)");
        break;
    case TYPE_MAESTRO2:
        strcpy(card->driver, "ES1968");
        strcpy(card->shortname, "ESS ES1968 (Maestro 2)");
        break;
    case TYPE_MAESTRO:
        strcpy(card->driver, "ESM1");
        strcpy(card->shortname, "ESS Maestro 1");
        break;
    }

    if ((err = snd_es1968_pcm(chip, 0)) < 0) {
        snd_card_free(card);
        return err;
    }
        printk("snd_es1968_probe cp5\n");


    if ((err = snd_es1968_mixer(chip)) < 0) {
        snd_card_free(card);
        return err;
    }

        printk("snd_es1968_probe cp6\n");

    if (enable_mpu[dev] == 2) {
        /* check the black list */
        unsigned short vend;
        pci_read_config_word(chip->pci, PCI_SUBSYSTEM_VENDOR_ID, &vend);
        for (i = 0; i < ARRAY_SIZE(mpu_blacklist); i++) {
            if (chip->type == mpu_blacklist[i].type &&
                vend == mpu_blacklist[i].vendor) {
                enable_mpu[dev] = 0;
                break;
            }
        }
    }
        printk("snd_es1968_probe cp7\n");

    if (enable_mpu[dev]) {
        if ((err = snd_mpu401_uart_new(card, 0, MPU401_HW_MPU401,
                                       chip->io_port + ESM_MPU401_PORT,
                                       MPU401_INFO_INTEGRATED,
                                       chip->irq, 0, &chip->rmidi)) < 0) {
            printk(KERN_WARNING "es1968: skipping MPU-401 MIDI support..\n");
        }
    }

        printk("snd_es1968_probe cp8\n");

    /* card switches */
    for (i = 0; i < num_controls(snd_es1968_control_switches); i++) {
        err = snd_ctl_add(card, snd_ctl_new1(&snd_es1968_control_switches[i], chip));
        if (err < 0) {
            snd_card_free(card);
            return err;
        }
    }
        printk("snd_es1968_probe cp9\n");


    snd_es1968_start_irq(chip);

    chip->clock = clock[dev];
    if (! chip->clock)
        es1968_measure_clock(chip);

        printk("snd_es1968_probe cp10\n");

    sprintf(card->longname, "%s at 0x%lx, irq %i",
            card->shortname, chip->io_port, chip->irq);

    if ((err = snd_card_register(card)) < 0) {
        snd_card_free(card);
        return err;
    }
        printk("snd_es1968_probe cp11\n");

    pci_set_drvdata(pci, card);
        printk("snd_es1968_probe cp12\n");

    dev++;
    return 0;
}

static void __devexit snd_es1968_remove(struct pci_dev *pci)
{
    snd_card_free(pci_get_drvdata(pci));
    pci_set_drvdata(pci, NULL);
}

static struct pci_driver driver = {
    0, 0, 0,
    "ES1968 (ESS Maestro)",
    snd_es1968_ids,
    snd_es1968_probe,
    snd_es1968_remove,
    SND_PCI_PM_CALLBACKS
};

static int __init alsa_card_es1968_init(void)
{
    int err;

    if ((err = pci_module_init(&driver)) < 0) {
#ifdef MODULE
        //              snd_printk("ESS Maestro soundcard not found or device busy\n");
#endif
        return err;
    }
    return 0;
}

static void __exit alsa_card_es1968_exit(void)
{
#if 0 // do we really need this?
    unregister_reboot_notifier(&snd_es1968_nb);
#endif
    pci_unregister_driver(&driver);
}

module_init(alsa_card_es1968_init)
module_exit(alsa_card_es1968_exit)

#ifndef MODULE

/* format is: snd-es1968=enable,index,id,
 total_bufsize,
 pcm_substreams_p,
 pcm_substreams_c,
 clock,
 use_pm,
 enable_mpu
 */

static int __init alsa_card_es1968_setup(char *str)
{
    static unsigned __initdata nr_dev = 0;

    if (nr_dev >= SNDRV_CARDS)
        return 0;
    (void)(get_option(&str,&enable[nr_dev]) == 2 &&
           get_option(&str,&index[nr_dev]) == 2 &&
           get_id(&str,&id[nr_dev]) == 2 &&
           get_option(&str,&total_bufsize[nr_dev]) == 2 &&
           get_option(&str,&pcm_substreams_p[nr_dev]) == 2 &&
           get_option(&str,&pcm_substreams_c[nr_dev]) == 2 &&
           get_option(&str,&clock[nr_dev]) == 2 &&
           get_option(&str,&use_pm[nr_dev]) == 2 &&
           get_option(&str,&enable_mpu[nr_dev]) == 2);
    nr_dev++;
    return 1;
}

__setup("snd-es1968=", alsa_card_es1968_setup);

#endif /* ifndef MODULE */