/*
 *  Copyright (c) by Francisco Moraes <fmoraes@nc.rr.com>
 *  Driver EMU10K1X chips
 *
 *  Parts of this code were adapted from audigyls.c driver which is
 *  Copyright (c) by James Courtier-Dutton <James@superbug.demon.co.uk>
 *
 *  BUGS:
 *    --
 *
 *  TODO:
 *
 *  Chips (SB0200 model):
 *    - EMU10K1X-DBQ
 *    - STAC 9708T
 *
 *   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
 *
 */
#include <sound/driver.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/moduleparam.h>
#include <sound/core.h>
#include <sound/initval.h>
#include <sound/pcm.h>
#include <sound/ac97_codec.h>
#include <sound/info.h>
#include <sound/rawmidi.h>

MODULE_AUTHOR("Francisco Moraes <fmoraes@nc.rr.com>");
MODULE_DESCRIPTION("EMU10K1X");
MODULE_LICENSE("GPL");
MODULE_SUPPORTED_DEVICE("{{Dell Creative Labs,SB Live!}");

// module parameters (see "Module Parameters")
static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;
static int enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP;

//module_param_array(index, int, NULL, 0444);
MODULE_PARM_DESC(index, "Index value for the EMU10K1X soundcard.");
//module_param_array(id, charp, NULL, 0444);
MODULE_PARM_DESC(id, "ID string for the EMU10K1X soundcard.");
//module_param_array(enable, bool, NULL, 0444);
MODULE_PARM_DESC(enable, "Enable the EMU10K1X soundcard.");


// some definitions were borrowed from emu10k1 driver as they seem to be the same
/************************************************************************************************/
/* PCI function 0 registers, address = <val> + PCIBASE0						*/
/************************************************************************************************/

#define PTR			0x00		/* Indexed register set pointer register	*/
/* NOTE: The CHANNELNUM and ADDRESS words can	*/
/* be modified independently of each other.	*/

#define DATA			0x04		/* Indexed register set data register		*/

#define IPR			0x08		/* Global interrupt pending register		*/
/* Clear pending interrupts by writing a 1 to	*/
/* the relevant bits and zero to the other bits	*/
#define IPR_MIDITRANSBUFEMPTY   0x00000001	/* MIDI UART transmit buffer empty		*/
#define IPR_MIDIRECVBUFEMPTY    0x00000002	/* MIDI UART receive buffer empty		*/
#define IPR_CH_0_LOOP           0x00000800      /* Channel 0 loop                               */
#define IPR_CH_0_HALF_LOOP      0x00000100      /* Channel 0 half loop                          */
#define IPR_CAP_0_LOOP          0x00080000      /* Channel capture loop                         */
#define IPR_CAP_0_HALF_LOOP     0x00010000      /* Channel capture half loop                    */

#define INTE			0x0c		/* Interrupt enable register			*/
#define INTE_MIDITXENABLE       0x00000001	/* Enable MIDI transmit-buffer-empty interrupts	*/
#define INTE_MIDIRXENABLE       0x00000002	/* Enable MIDI receive-buffer-empty interrupts	*/
#define INTE_CH_0_LOOP          0x00000800      /* Channel 0 loop                               */
#define INTE_CH_0_HALF_LOOP     0x00000100      /* Channel 0 half loop                          */
#define INTE_CAP_0_LOOP         0x00080000      /* Channel capture loop                         */
#define INTE_CAP_0_HALF_LOOP    0x00010000      /* Channel capture half loop                    */

#define HCFG			0x14		/* Hardware config register			*/

#define HCFG_LOCKSOUNDCACHE	0x00000008	/* 1 = Cancel bustmaster accesses to soundcache */
/* NOTE: This should generally never be used.  	*/
#define HCFG_AUDIOENABLE	0x00000001	/* 0 = CODECs transmit zero-valued samples	*/
/* Should be set to 1 when the EMU10K1 is	*/
/* completely initialized.			*/
#define GPIO			0x18		/* Defaults: 00001080-Analog, 00001000-SPDIF.   */


#define AC97DATA		0x1c		/* AC97 register set data register (16 bit)	*/

#define AC97ADDRESS		0x1e		/* AC97 register set address register (8 bit)	*/

/********************************************************************************************************/
/* Emu10k1x pointer-offset register set, accessed through the PTR and DATA registers			*/
/********************************************************************************************************/
#define PLAYBACK_LIST_ADDR	0x00		/* Base DMA address of a list of pointers to each period/size */
/* One list entry: 4 bytes for DMA address,
 * 4 bytes for period_size << 16.
 * One list entry is 8 bytes long.
 * One list entry for each period in the buffer.
 */
#define PLAYBACK_LIST_SIZE	0x01		/* Size of list in bytes << 16. E.g. 8 periods -> 0x00380000  */
#define PLAYBACK_LIST_PTR	0x02		/* Pointer to the current period being played */
#define PLAYBACK_DMA_ADDR	0x04		/* Playback DMA addresss */
#define PLAYBACK_PERIOD_SIZE	0x05		/* Playback period size */
#define PLAYBACK_POINTER	0x06		/* Playback period pointer. Sample currently in DAC */
#define PLAYBACK_UNKNOWN1       0x07
#define PLAYBACK_UNKNOWN2       0x08

/* Only one capture channel supported */
#define CAPTURE_DMA_ADDR	0x10		/* Capture DMA address */
#define CAPTURE_BUFFER_SIZE	0x11		/* Capture buffer size */
#define CAPTURE_POINTER		0x12		/* Capture buffer pointer. Sample currently in ADC */
#define CAPTURE_UNKNOWN         0x13

/* From 0x20 - 0x3f, last samples played on each channel */

#define TRIGGER_CHANNEL         0x40            /* Trigger channel playback                     */
#define TRIGGER_CHANNEL_0       0x00000001      /* Trigger channel 0                            */
#define TRIGGER_CHANNEL_1       0x00000002      /* Trigger channel 1                            */
#define TRIGGER_CHANNEL_2       0x00000004      /* Trigger channel 2                            */
#define TRIGGER_CAPTURE         0x00000100      /* Trigger capture channel                      */

#define ROUTING                 0x41            /* Setup sound routing ?                        */
#define ROUTING_FRONT_LEFT      0x00000001
#define ROUTING_FRONT_RIGHT     0x00000002
#define ROUTING_REAR_LEFT       0x00000004
#define ROUTING_REAR_RIGHT      0x00000008
#define ROUTING_CENTER_LFE      0x00010000

#define SPCS0			0x42		/* SPDIF output Channel Status 0 register	*/

#define SPCS1			0x43		/* SPDIF output Channel Status 1 register	*/

#define SPCS2			0x44		/* SPDIF output Channel Status 2 register	*/

#define SPCS_CLKACCYMASK	0x30000000	/* Clock accuracy				*/
#define SPCS_CLKACCY_1000PPM	0x00000000	/* 1000 parts per million			*/
#define SPCS_CLKACCY_50PPM	0x10000000	/* 50 parts per million				*/
#define SPCS_CLKACCY_VARIABLE	0x20000000	/* Variable accuracy				*/
#define SPCS_SAMPLERATEMASK	0x0f000000	/* Sample rate					*/
#define SPCS_SAMPLERATE_44	0x00000000	/* 44.1kHz sample rate				*/
#define SPCS_SAMPLERATE_48	0x02000000	/* 48kHz sample rate				*/
#define SPCS_SAMPLERATE_32	0x03000000	/* 32kHz sample rate				*/
#define SPCS_CHANNELNUMMASK	0x00f00000	/* Channel number				*/
#define SPCS_CHANNELNUM_UNSPEC	0x00000000	/* Unspecified channel number			*/
#define SPCS_CHANNELNUM_LEFT	0x00100000	/* Left channel					*/
#define SPCS_CHANNELNUM_RIGHT	0x00200000	/* Right channel				*/
#define SPCS_SOURCENUMMASK	0x000f0000	/* Source number				*/
#define SPCS_SOURCENUM_UNSPEC	0x00000000	/* Unspecified source number			*/
#define SPCS_GENERATIONSTATUS	0x00008000	/* Originality flag (see IEC-958 spec)		*/
#define SPCS_CATEGORYCODEMASK	0x00007f00	/* Category code (see IEC-958 spec)		*/
#define SPCS_MODEMASK		0x000000c0	/* Mode (see IEC-958 spec)			*/
#define SPCS_EMPHASISMASK	0x00000038	/* Emphasis					*/
#define SPCS_EMPHASIS_NONE	0x00000000	/* No emphasis					*/
#define SPCS_EMPHASIS_50_15	0x00000008	/* 50/15 usec 2 channel				*/
#define SPCS_COPYRIGHT		0x00000004	/* Copyright asserted flag -- do not modify	*/
#define SPCS_NOTAUDIODATA	0x00000002	/* 0 = Digital audio, 1 = not audio		*/
#define SPCS_PROFESSIONAL	0x00000001	/* 0 = Consumer (IEC-958), 1 = pro (AES3-1992)	*/

#define SPDIF_SELECT		0x45		/* Enables SPDIF or Analogue outputs 0-Analogue, 0x700-SPDIF */

/* This is the MPU port on the card                      					*/
#define MUDATA		0x47
#define MUCMD		0x48
#define MUSTAT		MUCMD

/* From 0x50 - 0x5f, last samples captured */

/**
 * The hardware has 3 channels for playback and 1 for capture.
 *  - channel 0 is the front channel
 *  - channel 1 is the rear channel
 *  - channel 2 is the center/lfe chanel
 * Volume is controlled by the AC97 for the front and rear channels by
 * the PCM Playback Volume, Sigmatel Surround Playback Volume and
 * Surround Playback Volume. The Sigmatel 4-Speaker Stereo switch affects
 * the front/rear channel mixing in the REAR OUT jack. When using the
 * 4-Speaker Stereo, both front and rear channels will be mixed in the
 * REAR OUT.
 * The center/lfe channel has no volume control and cannot be muted during
 * playback.
 */

struct emu10k1x_voice {
    struct emu10k1x *emu;
    int number;
    int use;

    struct emu10k1x_pcm *epcm;
};

struct emu10k1x_pcm {
    struct emu10k1x *emu;
    struct snd_pcm_substream *substream;
    struct emu10k1x_voice *voice;
    unsigned short running;
};

struct emu10k1x_midi {
    struct emu10k1x *emu;
    struct snd_rawmidi *rmidi;
    struct snd_rawmidi_substream *substream_input;
    struct snd_rawmidi_substream *substream_output;
    unsigned int midi_mode;
    spinlock_t input_lock;
    spinlock_t output_lock;
    spinlock_t open_lock;
    int tx_enable, rx_enable;
    int port;
    int ipr_tx, ipr_rx;
    void (*interrupt)(struct emu10k1x *emu, unsigned int status);
};

// definition of the chip-specific record
struct emu10k1x {
    struct snd_card *card;
    struct pci_dev *pci;

    unsigned long port;
    struct resource *res_port;
    int irq;

    unsigned int revision;		/* chip revision */
    unsigned int serial;            /* serial number */
    unsigned short model;		/* subsystem id */

    spinlock_t emu_lock;
    spinlock_t voice_lock;

    struct snd_ac97 *ac97;
    struct snd_pcm *pcm;

    struct emu10k1x_voice voices[3];
    struct emu10k1x_voice capture_voice;
    u32 spdif_bits[3]; // SPDIF out setup

    struct snd_dma_buffer dma_buffer;

    struct emu10k1x_midi midi;
};

/* hardware definition */
static struct snd_pcm_hardware snd_emu10k1x_playback_hw = {
    .info =			(SNDRV_PCM_INFO_MMAP |
                                 SNDRV_PCM_INFO_INTERLEAVED |
                                 SNDRV_PCM_INFO_BLOCK_TRANSFER |
                                 SNDRV_PCM_INFO_MMAP_VALID),
                                 .formats =		SNDRV_PCM_FMTBIT_S16_LE,
                                 .rates =		SNDRV_PCM_RATE_48000,
                                 .rate_min =		48000,
                                 .rate_max =		48000,
                                 .channels_min =		2,
                                 .channels_max =		2,
                                 .buffer_bytes_max =	(32*1024),
                                 .period_bytes_min =	64,
                                 .period_bytes_max =	(16*1024),
                                 .periods_min =		2,
                                 .periods_max =		8,
                                 .fifo_size =		0,
};

static struct snd_pcm_hardware snd_emu10k1x_capture_hw = {
    .info =			(SNDRV_PCM_INFO_MMAP |
                                 SNDRV_PCM_INFO_INTERLEAVED |
                                 SNDRV_PCM_INFO_BLOCK_TRANSFER |
                                 SNDRV_PCM_INFO_MMAP_VALID),
                                 .formats =		SNDRV_PCM_FMTBIT_S16_LE,
                                 .rates =		SNDRV_PCM_RATE_48000,
                                 .rate_min =		48000,
                                 .rate_max =		48000,
                                 .channels_min =		2,
                                 .channels_max =		2,
                                 .buffer_bytes_max =	(32*1024),
                                 .period_bytes_min =	64,
                                 .period_bytes_max =	(16*1024),
                                 .periods_min =		2,
                                 .periods_max =		2,
                                 .fifo_size =		0,
};

static unsigned int snd_emu10k1x_ptr_read(struct emu10k1x * emu,
                                          unsigned int reg,
                                          unsigned int chn)
{
    unsigned long flags;
    unsigned int regptr, val;

    regptr = (reg << 16) | chn;

    spin_lock_irqsave(&emu->emu_lock, flags);
    outl(regptr, emu->port + PTR);
    val = inl(emu->port + DATA);
    spin_unlock_irqrestore(&emu->emu_lock, flags);
    return val;
}

static void snd_emu10k1x_ptr_write(struct emu10k1x *emu,
                                   unsigned int reg,
                                   unsigned int chn,
                                   unsigned int data)
{
    unsigned int regptr;
    unsigned long flags;

    regptr = (reg << 16) | chn;

    spin_lock_irqsave(&emu->emu_lock, flags);
    outl(regptr, emu->port + PTR);
    outl(data, emu->port + DATA);
    spin_unlock_irqrestore(&emu->emu_lock, flags);
}

static void snd_emu10k1x_intr_enable(struct emu10k1x *emu, unsigned int intrenb)
{
    unsigned long flags;
    unsigned int enable;

    spin_lock_irqsave(&emu->emu_lock, flags);
    enable = inl(emu->port + INTE) | intrenb;
    outl(enable, emu->port + INTE);
    spin_unlock_irqrestore(&emu->emu_lock, flags);
}

static void snd_emu10k1x_intr_disable(struct emu10k1x *emu, unsigned int intrenb)
{
    unsigned long flags;
    unsigned int enable;

    spin_lock_irqsave(&emu->emu_lock, flags);
    enable = inl(emu->port + INTE) & ~intrenb;
    outl(enable, emu->port + INTE);
    spin_unlock_irqrestore(&emu->emu_lock, flags);
}

static void snd_emu10k1x_gpio_write(struct emu10k1x *emu, unsigned int value)
{
    unsigned long flags;

    spin_lock_irqsave(&emu->emu_lock, flags);
    outl(value, emu->port + GPIO);
    spin_unlock_irqrestore(&emu->emu_lock, flags);
}

static void snd_emu10k1x_pcm_free_substream(struct snd_pcm_runtime *runtime)
{
    kfree(runtime->private_data);
}

static void snd_emu10k1x_pcm_interrupt(struct emu10k1x *emu, struct emu10k1x_voice *voice)
{
    struct emu10k1x_pcm *epcm;

    if ((epcm = voice->epcm) == NULL)
        return;
    if (epcm->substream == NULL)
        return;
#if 0
    snd_printk(KERN_INFO "IRQ: position = 0x%x, period = 0x%x, size = 0x%x\n",
               epcm->substream->ops->pointer(epcm->substream),
               snd_pcm_lib_period_bytes(epcm->substream),
               snd_pcm_lib_buffer_bytes(epcm->substream));
#endif
    snd_pcm_period_elapsed(epcm->substream);
}

/* open callback */
static int snd_emu10k1x_playback_open(struct snd_pcm_substream *substream)
{
    struct emu10k1x *chip = snd_pcm_substream_chip(substream);
    struct emu10k1x_pcm *epcm;
    struct snd_pcm_runtime *runtime = substream->runtime;
    int err;

    if ((err = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS)) < 0) {
        return err;
    }
    if ((err = snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 64)) < 0)
        return err;

    epcm = (struct emu10k1x_pcm *)kzalloc(sizeof(*epcm), GFP_KERNEL);
    if (epcm == NULL)
        return -ENOMEM;
    epcm->emu = chip;
    epcm->substream = substream;

    runtime->private_data = epcm;
    runtime->private_free = snd_emu10k1x_pcm_free_substream;

    runtime->hw = snd_emu10k1x_playback_hw;

    return 0;
}

/* close callback */
static int snd_emu10k1x_playback_close(struct snd_pcm_substream *substream)
{
    return 0;
}

/* hw_params callback */
static int snd_emu10k1x_pcm_hw_params(struct snd_pcm_substream *substream,
                                      struct snd_pcm_hw_params *hw_params)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    struct emu10k1x_pcm *epcm = runtime->private_data;

    if (! epcm->voice) {
        epcm->voice = &epcm->emu->voices[substream->pcm->device];
        epcm->voice->use = 1;
        epcm->voice->epcm = epcm;
    }

    return snd_pcm_lib_malloc_pages(substream,
                                    params_buffer_bytes(hw_params));
}

/* hw_free callback */
static int snd_emu10k1x_pcm_hw_free(struct snd_pcm_substream *substream)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    struct emu10k1x_pcm *epcm;

    if (runtime->private_data == NULL)
        return 0;

    epcm = runtime->private_data;

    if (epcm->voice) {
        epcm->voice->use = 0;
        epcm->voice->epcm = NULL;
        epcm->voice = NULL;
    }

    return snd_pcm_lib_free_pages(substream);
}

/* prepare callback */
static int snd_emu10k1x_pcm_prepare(struct snd_pcm_substream *substream)
{
    struct emu10k1x *emu = snd_pcm_substream_chip(substream);
    struct snd_pcm_runtime *runtime = substream->runtime;
    struct emu10k1x_pcm *epcm = runtime->private_data;
    int voice = epcm->voice->number;
    u32 *table_base = (u32 *)(emu->dma_buffer.area+1024*voice);
    u32 period_size_bytes = frames_to_bytes(runtime, runtime->period_size);
    int i;

    for(i=0; i < runtime->periods; i++) {
        *table_base++=runtime->dma_addr+(i*period_size_bytes);
        *table_base++=period_size_bytes<<16;
    }

    snd_emu10k1x_ptr_write(emu, PLAYBACK_LIST_ADDR, voice, emu->dma_buffer.addr+1024*voice);
    snd_emu10k1x_ptr_write(emu, PLAYBACK_LIST_SIZE, voice, (runtime->periods - 1) << 19);
    snd_emu10k1x_ptr_write(emu, PLAYBACK_LIST_PTR, voice, 0);
    snd_emu10k1x_ptr_write(emu, PLAYBACK_POINTER, voice, 0);
    snd_emu10k1x_ptr_write(emu, PLAYBACK_UNKNOWN1, voice, 0);
    snd_emu10k1x_ptr_write(emu, PLAYBACK_UNKNOWN2, voice, 0);
    snd_emu10k1x_ptr_write(emu, PLAYBACK_DMA_ADDR, voice, runtime->dma_addr);

    snd_emu10k1x_ptr_write(emu, PLAYBACK_PERIOD_SIZE, voice, frames_to_bytes(runtime, runtime->period_size)<<16);

    return 0;
}

/* trigger callback */
static int snd_emu10k1x_pcm_trigger(struct snd_pcm_substream *substream,
                                    int cmd)
{
    struct emu10k1x *emu = snd_pcm_substream_chip(substream);
    struct snd_pcm_runtime *runtime = substream->runtime;
    struct emu10k1x_pcm *epcm = runtime->private_data;
    int channel = epcm->voice->number;
    int result = 0;

    //	snd_printk(KERN_INFO "trigger - emu10k1x = 0x%x, cmd = %i, pointer = %d\n", (int)emu, cmd, (int)substream->ops->pointer(substream));

    switch (cmd) {
    case SNDRV_PCM_TRIGGER_START:
        if(runtime->periods == 2)
            snd_emu10k1x_intr_enable(emu, (INTE_CH_0_LOOP | INTE_CH_0_HALF_LOOP) << channel);
        else
            snd_emu10k1x_intr_enable(emu, INTE_CH_0_LOOP << channel);
        epcm->running = 1;
        snd_emu10k1x_ptr_write(emu, TRIGGER_CHANNEL, 0, snd_emu10k1x_ptr_read(emu, TRIGGER_CHANNEL, 0)|(TRIGGER_CHANNEL_0<<channel));
        break;
    case SNDRV_PCM_TRIGGER_STOP:
        epcm->running = 0;
        snd_emu10k1x_intr_disable(emu, (INTE_CH_0_LOOP | INTE_CH_0_HALF_LOOP) << channel);
        snd_emu10k1x_ptr_write(emu, TRIGGER_CHANNEL, 0, snd_emu10k1x_ptr_read(emu, TRIGGER_CHANNEL, 0) & ~(TRIGGER_CHANNEL_0<<channel));
        break;
    default:
        result = -EINVAL;
        break;
    }
    return result;
}

/* pointer callback */
static snd_pcm_uframes_t
snd_emu10k1x_pcm_pointer(struct snd_pcm_substream *substream)
{
    struct emu10k1x *emu = snd_pcm_substream_chip(substream);
    struct snd_pcm_runtime *runtime = substream->runtime;
    struct emu10k1x_pcm *epcm = runtime->private_data;
    int channel = epcm->voice->number;
    snd_pcm_uframes_t ptr = 0, ptr1 = 0, ptr2= 0,ptr3 = 0,ptr4 = 0;

    if (!epcm->running)
        return 0;

    ptr3 = snd_emu10k1x_ptr_read(emu, PLAYBACK_LIST_PTR, channel);
    ptr1 = snd_emu10k1x_ptr_read(emu, PLAYBACK_POINTER, channel);
    ptr4 = snd_emu10k1x_ptr_read(emu, PLAYBACK_LIST_PTR, channel);

    if(ptr4 == 0 && ptr1 == frames_to_bytes(runtime, runtime->buffer_size))
        return 0;

    if (ptr3 != ptr4)
        ptr1 = snd_emu10k1x_ptr_read(emu, PLAYBACK_POINTER, channel);
    ptr2 = bytes_to_frames(runtime, ptr1);
    ptr2 += (ptr4 >> 3) * runtime->period_size;
    ptr = ptr2;

    if (ptr >= runtime->buffer_size)
        ptr -= runtime->buffer_size;

    return ptr;
}

/* operators */
static struct snd_pcm_ops snd_emu10k1x_playback_ops = {
    .open =        snd_emu10k1x_playback_open,
    .close =       snd_emu10k1x_playback_close,
    .ioctl =       snd_pcm_lib_ioctl,
    .hw_params =   snd_emu10k1x_pcm_hw_params,
    .hw_free =     snd_emu10k1x_pcm_hw_free,
    .prepare =     snd_emu10k1x_pcm_prepare,
    .trigger =     snd_emu10k1x_pcm_trigger,
    .pointer =     snd_emu10k1x_pcm_pointer,
};

/* open_capture callback */
static int snd_emu10k1x_pcm_open_capture(struct snd_pcm_substream *substream)
{
    struct emu10k1x *chip = snd_pcm_substream_chip(substream);
    struct emu10k1x_pcm *epcm;
    struct snd_pcm_runtime *runtime = substream->runtime;
    int err;

    if ((err = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS)) < 0)
        return err;
    if ((err = snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 64)) < 0)
        return err;

    epcm = (struct emu10k1x_pcm *)kzalloc(sizeof(*epcm), GFP_KERNEL);
    if (epcm == NULL)
        return -ENOMEM;

    epcm->emu = chip;
    epcm->substream = substream;

    runtime->private_data = epcm;
    runtime->private_free = snd_emu10k1x_pcm_free_substream;

    runtime->hw = snd_emu10k1x_capture_hw;

    return 0;
}

/* close callback */
static int snd_emu10k1x_pcm_close_capture(struct snd_pcm_substream *substream)
{
    return 0;
}

/* hw_params callback */
static int snd_emu10k1x_pcm_hw_params_capture(struct snd_pcm_substream *substream,
                                              struct snd_pcm_hw_params *hw_params)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    struct emu10k1x_pcm *epcm = runtime->private_data;

    if (! epcm->voice) {
        if (epcm->emu->capture_voice.use)
            return -EBUSY;
        epcm->voice = &epcm->emu->capture_voice;
        epcm->voice->epcm = epcm;
        epcm->voice->use = 1;
    }

    return snd_pcm_lib_malloc_pages(substream,
                                    params_buffer_bytes(hw_params));
}

/* hw_free callback */
static int snd_emu10k1x_pcm_hw_free_capture(struct snd_pcm_substream *substream)
{
    struct snd_pcm_runtime *runtime = substream->runtime;

    struct emu10k1x_pcm *epcm;

    if (runtime->private_data == NULL)
        return 0;
    epcm = runtime->private_data;

    if (epcm->voice) {
        epcm->voice->use = 0;
        epcm->voice->epcm = NULL;
        epcm->voice = NULL;
    }

    return snd_pcm_lib_free_pages(substream);
}

/* prepare capture callback */
static int snd_emu10k1x_pcm_prepare_capture(struct snd_pcm_substream *substream)
{
    struct emu10k1x *emu = snd_pcm_substream_chip(substream);
    struct snd_pcm_runtime *runtime = substream->runtime;

    snd_emu10k1x_ptr_write(emu, CAPTURE_DMA_ADDR, 0, runtime->dma_addr);
    snd_emu10k1x_ptr_write(emu, CAPTURE_BUFFER_SIZE, 0, frames_to_bytes(runtime, runtime->buffer_size)<<16); // buffer size in bytes
    snd_emu10k1x_ptr_write(emu, CAPTURE_POINTER, 0, 0);
    snd_emu10k1x_ptr_write(emu, CAPTURE_UNKNOWN, 0, 0);

    return 0;
}

/* trigger_capture callback */
static int snd_emu10k1x_pcm_trigger_capture(struct snd_pcm_substream *substream,
                                            int cmd)
{
    struct emu10k1x *emu = snd_pcm_substream_chip(substream);
    struct snd_pcm_runtime *runtime = substream->runtime;
    struct emu10k1x_pcm *epcm = runtime->private_data;
    int result = 0;

    switch (cmd) {
    case SNDRV_PCM_TRIGGER_START:
        snd_emu10k1x_intr_enable(emu, INTE_CAP_0_LOOP |
                                 INTE_CAP_0_HALF_LOOP);
        snd_emu10k1x_ptr_write(emu, TRIGGER_CHANNEL, 0, snd_emu10k1x_ptr_read(emu, TRIGGER_CHANNEL, 0)|TRIGGER_CAPTURE);
        epcm->running = 1;
        break;
    case SNDRV_PCM_TRIGGER_STOP:
        epcm->running = 0;
        snd_emu10k1x_intr_disable(emu, INTE_CAP_0_LOOP |
                                  INTE_CAP_0_HALF_LOOP);
        snd_emu10k1x_ptr_write(emu, TRIGGER_CHANNEL, 0, snd_emu10k1x_ptr_read(emu, TRIGGER_CHANNEL, 0) & ~(TRIGGER_CAPTURE));
        break;
    default:
        result = -EINVAL;
        break;
    }
    return result;
}

/* pointer_capture callback */
static snd_pcm_uframes_t
snd_emu10k1x_pcm_pointer_capture(struct snd_pcm_substream *substream)
{
    struct emu10k1x *emu = snd_pcm_substream_chip(substream);
    struct snd_pcm_runtime *runtime = substream->runtime;
    struct emu10k1x_pcm *epcm = runtime->private_data;
    snd_pcm_uframes_t ptr;

    if (!epcm->running)
        return 0;

    ptr = bytes_to_frames(runtime, snd_emu10k1x_ptr_read(emu, CAPTURE_POINTER, 0));
    if (ptr >= runtime->buffer_size)
        ptr -= runtime->buffer_size;

    return ptr;
}

static struct snd_pcm_ops snd_emu10k1x_capture_ops = {
    .open =        snd_emu10k1x_pcm_open_capture,
    .close =       snd_emu10k1x_pcm_close_capture,
    .ioctl =       snd_pcm_lib_ioctl,
    .hw_params =   snd_emu10k1x_pcm_hw_params_capture,
    .hw_free =     snd_emu10k1x_pcm_hw_free_capture,
    .prepare =     snd_emu10k1x_pcm_prepare_capture,
    .trigger =     snd_emu10k1x_pcm_trigger_capture,
    .pointer =     snd_emu10k1x_pcm_pointer_capture,
};

static unsigned short snd_emu10k1x_ac97_read(struct snd_ac97 *ac97,
                                             unsigned short reg)
{
    struct emu10k1x *emu = ac97->private_data;
    unsigned long flags;
    unsigned short val;

    spin_lock_irqsave(&emu->emu_lock, flags);
    outb(reg, emu->port + AC97ADDRESS);
    val = inw(emu->port + AC97DATA);
    spin_unlock_irqrestore(&emu->emu_lock, flags);
    return val;
}

static void snd_emu10k1x_ac97_write(struct snd_ac97 *ac97,
                                    unsigned short reg, unsigned short val)
{
    struct emu10k1x *emu = ac97->private_data;
    unsigned long flags;

    spin_lock_irqsave(&emu->emu_lock, flags);
    outb(reg, emu->port + AC97ADDRESS);
    outw(val, emu->port + AC97DATA);
    spin_unlock_irqrestore(&emu->emu_lock, flags);
}

static int snd_emu10k1x_ac97(struct emu10k1x *chip)
{
    struct snd_ac97_bus *pbus;
    struct snd_ac97_template ac97;
    int err;
    static struct snd_ac97_bus_ops ops = {
        .write = snd_emu10k1x_ac97_write,
        .read = snd_emu10k1x_ac97_read,
    };

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

    memset(&ac97, 0, sizeof(ac97));
    ac97.private_data = chip;
    ac97.scaps = AC97_SCAP_NO_SPDIF;
    return snd_ac97_mixer(pbus, &ac97, &chip->ac97);
}

static int snd_emu10k1x_free(struct emu10k1x *chip)
{
    snd_emu10k1x_ptr_write(chip, TRIGGER_CHANNEL, 0, 0);
    // disable interrupts
    outl(0, chip->port + INTE);
    // disable audio
    outl(HCFG_LOCKSOUNDCACHE, chip->port + HCFG);

    // release the i/o port
    release_and_free_resource(chip->res_port);

    // release the irq
    if (chip->irq >= 0)
        free_irq(chip->irq, (void *)chip);

    // release the DMA
    if (chip->dma_buffer.area) {
        snd_dma_free_pages(&chip->dma_buffer);
    }

    pci_disable_device(chip->pci);

    // release the data
    kfree(chip);
    return 0;
}

static int snd_emu10k1x_dev_free(struct snd_device *device)
{
    struct emu10k1x *chip = device->device_data;
    return snd_emu10k1x_free(chip);
}

static irqreturn_t snd_emu10k1x_interrupt(int irq, void *dev_id, struct pt_regs *unused)
{
    unsigned int status;

    struct emu10k1x *chip = dev_id;
    struct emu10k1x_voice *pvoice = chip->voices;
    int i;
    int mask;

    status = inl(chip->port + IPR);

    if (! status)
        return IRQ_NONE;

    // capture interrupt
    if (status & (IPR_CAP_0_LOOP | IPR_CAP_0_HALF_LOOP)) {
        struct emu10k1x_voice *pvoice = &chip->capture_voice;
        if (pvoice->use)
            snd_emu10k1x_pcm_interrupt(chip, pvoice);
        else
            snd_emu10k1x_intr_disable(chip,
                                      INTE_CAP_0_LOOP |
                                      INTE_CAP_0_HALF_LOOP);
    }

    mask = IPR_CH_0_LOOP|IPR_CH_0_HALF_LOOP;
    for (i = 0; i < 3; i++) {
        if (status & mask) {
            if (pvoice->use)
                snd_emu10k1x_pcm_interrupt(chip, pvoice);
            else
                snd_emu10k1x_intr_disable(chip, mask);
        }
        pvoice++;
        mask <<= 1;
    }

    if (status & (IPR_MIDITRANSBUFEMPTY|IPR_MIDIRECVBUFEMPTY)) {
        if (chip->midi.interrupt)
            chip->midi.interrupt(chip, status);
        else
            snd_emu10k1x_intr_disable(chip, INTE_MIDITXENABLE|INTE_MIDIRXENABLE);
    }

    // acknowledge the interrupt if necessary
    outl(status, chip->port + IPR);

    // snd_printk(KERN_INFO "interrupt %08x\n", status);
    return IRQ_HANDLED;
}

static int __devinit snd_emu10k1x_pcm(struct emu10k1x *emu, int device, struct snd_pcm **rpcm)
{
    struct snd_pcm *pcm;
    int err;
    int capture = 0;

    if (rpcm)
        *rpcm = NULL;
    if (device == 0)
        capture = 1;

    if ((err = snd_pcm_new(emu->card, "emu10k1x", device, 1, capture, &pcm)) < 0)
        return err;

    pcm->private_data = emu;

    switch(device) {
    case 0:
        snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_emu10k1x_playback_ops);
        snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_emu10k1x_capture_ops);
        break;
    case 1:
    case 2:
        snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_emu10k1x_playback_ops);
        break;
    }

    pcm->info_flags = 0;
    pcm->dev_subclass = SNDRV_PCM_SUBCLASS_GENERIC_MIX;
    switch(device) {
    case 0:
        strcpy(pcm->name, "EMU10K1X Front");
        break;
    case 1:
        strcpy(pcm->name, "EMU10K1X Rear");
        break;
    case 2:
        strcpy(pcm->name, "EMU10K1X Center/LFE");
        break;
    }
    emu->pcm = pcm;

    snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
                                          snd_dma_pci_data(emu->pci),
                                          32*1024, 32*1024);

    if (rpcm)
        *rpcm = pcm;

    return 0;
}

static int __devinit snd_emu10k1x_create(struct snd_card *card,
                                         struct pci_dev *pci,
                                         struct emu10k1x **rchip)
{
    struct emu10k1x *chip;
    int err;
    int ch;
    static struct snd_device_ops ops = {
        .dev_free = snd_emu10k1x_dev_free,
    };

    *rchip = NULL;

    if ((err = pci_enable_device(pci)) < 0)
        return err;
    pci_set_dma_mask(pci, 0x0fffffff);

    chip = (struct emu10k1x *)kzalloc(sizeof(*chip), GFP_KERNEL);
    if (chip == NULL) {
        pci_disable_device(pci);
        return -ENOMEM;
    }

    chip->card = card;
    chip->pci = pci;
    chip->irq = -1;

    spin_lock_init(&chip->emu_lock);
    spin_lock_init(&chip->voice_lock);

    chip->port = pci_resource_start(pci, 0);
    if ((chip->res_port = request_region(chip->port, 8,
                                         "EMU10K1X")) == NULL) {
        snd_printk(KERN_ERR "emu10k1x: cannot allocate the port 0x%lx\n", chip->port);
        snd_emu10k1x_free(chip);
        return -EBUSY;
    }

    if (request_irq(pci->irq, snd_emu10k1x_interrupt,
                    SA_INTERRUPT|SA_SHIRQ, "EMU10K1X",
                    (void *)chip)) {
        snd_printk(KERN_ERR "emu10k1x: cannot grab irq %d\n", pci->irq);
        snd_emu10k1x_free(chip);
        return -EBUSY;
    }
    chip->irq = pci->irq;

    if(snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, snd_dma_pci_data(pci),
                           4 * 1024, &chip->dma_buffer) < 0) {
        snd_emu10k1x_free(chip);
        return -ENOMEM;
    }

    pci_set_master(pci);
    /* read revision & serial */
    pci_read_config_byte(pci, PCI_REVISION_ID, (char *)&chip->revision);
    pci_read_config_dword(pci, PCI_SUBSYSTEM_VENDOR_ID, &chip->serial);
    pci_read_config_word(pci, PCI_SUBSYSTEM_ID, &chip->model);
    snd_printk(KERN_INFO "Model %04x Rev %08x Serial %08x\n", chip->model,
               chip->revision, chip->serial);

    outl(0, chip->port + INTE);

    for(ch = 0; ch < 3; ch++) {
        chip->voices[ch].emu = chip;
        chip->voices[ch].number = ch;
    }

    /*
     *  Init to 0x02109204 :
     *  Clock accuracy    = 0     (1000ppm)
     *  Sample Rate       = 2     (48kHz)
     *  Audio Channel     = 1     (Left of 2)
     *  Source Number     = 0     (Unspecified)
     *  Generation Status = 1     (Original for Cat Code 12)
     *  Cat Code          = 12    (Digital Signal Mixer)
     *  Mode              = 0     (Mode 0)
     *  Emphasis          = 0     (None)
     *  CP                = 1     (Copyright unasserted)
     *  AN                = 0     (Audio data)
     *  P                 = 0     (Consumer)
     */
    snd_emu10k1x_ptr_write(chip, SPCS0, 0,
                           chip->spdif_bits[0] =
                           SPCS_CLKACCY_1000PPM | SPCS_SAMPLERATE_48 |
                           SPCS_CHANNELNUM_LEFT | SPCS_SOURCENUM_UNSPEC |
                           SPCS_GENERATIONSTATUS | 0x00001200 |
                           0x00000000 | SPCS_EMPHASIS_NONE | SPCS_COPYRIGHT);
    snd_emu10k1x_ptr_write(chip, SPCS1, 0,
                           chip->spdif_bits[1] =
                           SPCS_CLKACCY_1000PPM | SPCS_SAMPLERATE_48 |
                           SPCS_CHANNELNUM_LEFT | SPCS_SOURCENUM_UNSPEC |
                           SPCS_GENERATIONSTATUS | 0x00001200 |
                           0x00000000 | SPCS_EMPHASIS_NONE | SPCS_COPYRIGHT);
    snd_emu10k1x_ptr_write(chip, SPCS2, 0,
                           chip->spdif_bits[2] =
                           SPCS_CLKACCY_1000PPM | SPCS_SAMPLERATE_48 |
                           SPCS_CHANNELNUM_LEFT | SPCS_SOURCENUM_UNSPEC |
                           SPCS_GENERATIONSTATUS | 0x00001200 |
                           0x00000000 | SPCS_EMPHASIS_NONE | SPCS_COPYRIGHT);

    snd_emu10k1x_ptr_write(chip, SPDIF_SELECT, 0, 0x700); // disable SPDIF
    snd_emu10k1x_ptr_write(chip, ROUTING, 0, 0x1003F); // routing
    snd_emu10k1x_gpio_write(chip, 0x1080); // analog mode

    outl(HCFG_LOCKSOUNDCACHE|HCFG_AUDIOENABLE, chip->port+HCFG);

    if ((err = snd_device_new(card, SNDRV_DEV_LOWLEVEL,
                              chip, &ops)) < 0) {
        snd_emu10k1x_free(chip);
        return err;
    }
    *rchip = chip;
    return 0;
}

static void snd_emu10k1x_proc_reg_read(struct snd_info_entry *entry,
                                       struct snd_info_buffer *buffer)
{
    struct emu10k1x *emu = entry->private_data;
    unsigned long value,value1,value2;
    unsigned long flags;
    int i;

    snd_iprintf(buffer, "Registers:\n\n");
    for(i = 0; i < 0x20; i+=4) {
        spin_lock_irqsave(&emu->emu_lock, flags);
        value = inl(emu->port + i);
        spin_unlock_irqrestore(&emu->emu_lock, flags);
        snd_iprintf(buffer, "Register %02X: %08lX\n", i, value);
    }
    snd_iprintf(buffer, "\nRegisters\n\n");
    for(i = 0; i <= 0x48; i++) {
        value = snd_emu10k1x_ptr_read(emu, i, 0);
        if(i < 0x10 || (i >= 0x20 && i < 0x40)) {
            value1 = snd_emu10k1x_ptr_read(emu, i, 1);
            value2 = snd_emu10k1x_ptr_read(emu, i, 2);
            snd_iprintf(buffer, "%02X: %08lX %08lX %08lX\n", i, value, value1, value2);
        } else {
            snd_iprintf(buffer, "%02X: %08lX\n", i, value);
        }
    }
}

static void snd_emu10k1x_proc_reg_write(struct snd_info_entry *entry,
                                        struct snd_info_buffer *buffer)
{
    struct emu10k1x *emu = entry->private_data;
    char line[64];
    unsigned int reg, channel_id , val;
#if 0
    while (!snd_info_get_line(buffer, line, sizeof(line))) {
        if (sscanf(line, "%x %x %x", &reg, &channel_id, &val) != 3)
            continue;

        if ((reg < 0x49) && (reg >=0) && (val <= 0xffffffff)
            && (channel_id >=0) && (channel_id <= 2) )
            snd_emu10k1x_ptr_write(emu, reg, channel_id, val);
    }
#endif
}

static int __devinit snd_emu10k1x_proc_init(struct emu10k1x * emu)
{
    struct snd_info_entry *entry;

    if(! snd_card_proc_new(emu->card, "emu10k1x_regs", &entry)) {
        snd_info_set_text_ops(entry, emu, 1024, snd_emu10k1x_proc_reg_read);
        entry->c.text.write_size = 64;
        entry->c.text.write = snd_emu10k1x_proc_reg_write;
        entry->mode |= S_IWUSR;
        entry->private_data = emu;
    }

    return 0;
}

static int snd_emu10k1x_shared_spdif_info(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_info *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_emu10k1x_shared_spdif_get(struct snd_kcontrol *kcontrol,
                                         struct snd_ctl_elem_value *ucontrol)
{
    struct emu10k1x *emu = snd_kcontrol_chip(kcontrol);

    ucontrol->value.integer.value[0] = (snd_emu10k1x_ptr_read(emu, SPDIF_SELECT, 0) == 0x700) ? 0 : 1;

    return 0;
}

static int snd_emu10k1x_shared_spdif_put(struct snd_kcontrol *kcontrol,
                                         struct snd_ctl_elem_value *ucontrol)
{
    struct emu10k1x *emu = snd_kcontrol_chip(kcontrol);
    unsigned int val;
    int change = 0;

    val = ucontrol->value.integer.value[0] ;

    if (val) {
        // enable spdif output
        snd_emu10k1x_ptr_write(emu, SPDIF_SELECT, 0, 0x000);
        snd_emu10k1x_ptr_write(emu, ROUTING, 0, 0x700);
        snd_emu10k1x_gpio_write(emu, 0x1000);
    } else {
        // disable spdif output
        snd_emu10k1x_ptr_write(emu, SPDIF_SELECT, 0, 0x700);
        snd_emu10k1x_ptr_write(emu, ROUTING, 0, 0x1003F);
        snd_emu10k1x_gpio_write(emu, 0x1080);
    }
    return change;
}

static struct snd_kcontrol_new snd_emu10k1x_shared_spdif __devinitdata =
{
    .iface =	SNDRV_CTL_ELEM_IFACE_MIXER,
    .name =		"Analog/Digital Output Jack",
    .info =		snd_emu10k1x_shared_spdif_info,
    .get =		snd_emu10k1x_shared_spdif_get,
    .put =		snd_emu10k1x_shared_spdif_put
};

static int snd_emu10k1x_spdif_info(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_info *uinfo)
{
    uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
    uinfo->count = 1;
    return 0;
}

static int snd_emu10k1x_spdif_get(struct snd_kcontrol *kcontrol,
                                  struct snd_ctl_elem_value *ucontrol)
{
    struct emu10k1x *emu = snd_kcontrol_chip(kcontrol);
    unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);

    ucontrol->value.iec958.status[0] = (emu->spdif_bits[idx] >> 0) & 0xff;
    ucontrol->value.iec958.status[1] = (emu->spdif_bits[idx] >> 8) & 0xff;
    ucontrol->value.iec958.status[2] = (emu->spdif_bits[idx] >> 16) & 0xff;
    ucontrol->value.iec958.status[3] = (emu->spdif_bits[idx] >> 24) & 0xff;
    return 0;
}

static int snd_emu10k1x_spdif_get_mask(struct snd_kcontrol *kcontrol,
                                       struct snd_ctl_elem_value *ucontrol)
{
    ucontrol->value.iec958.status[0] = 0xff;
    ucontrol->value.iec958.status[1] = 0xff;
    ucontrol->value.iec958.status[2] = 0xff;
    ucontrol->value.iec958.status[3] = 0xff;
    return 0;
}

static int snd_emu10k1x_spdif_put(struct snd_kcontrol *kcontrol,
                                  struct snd_ctl_elem_value *ucontrol)
{
    struct emu10k1x *emu = snd_kcontrol_chip(kcontrol);
    unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
    int change;
    unsigned int val;

    val = (ucontrol->value.iec958.status[0] << 0) |
        (ucontrol->value.iec958.status[1] << 8) |
        (ucontrol->value.iec958.status[2] << 16) |
        (ucontrol->value.iec958.status[3] << 24);
    change = val != emu->spdif_bits[idx];
    if (change) {
        snd_emu10k1x_ptr_write(emu, SPCS0 + idx, 0, val);
        emu->spdif_bits[idx] = val;
    }
    return change;
}

static struct snd_kcontrol_new snd_emu10k1x_spdif_mask_control =
{
    .access =	SNDRV_CTL_ELEM_ACCESS_READ,
    .iface =        SNDRV_CTL_ELEM_IFACE_PCM,
    .name =         SNDRV_CTL_NAME_IEC958("",PLAYBACK,MASK),
    .count =	3,
    .info =         snd_emu10k1x_spdif_info,
    .get =          snd_emu10k1x_spdif_get_mask
};

static struct snd_kcontrol_new snd_emu10k1x_spdif_control =
{
    .iface =	SNDRV_CTL_ELEM_IFACE_PCM,
    .name =         SNDRV_CTL_NAME_IEC958("",PLAYBACK,DEFAULT),
    .count =	3,
    .info =         snd_emu10k1x_spdif_info,
    .get =          snd_emu10k1x_spdif_get,
    .put =          snd_emu10k1x_spdif_put
};

static int __devinit snd_emu10k1x_mixer(struct emu10k1x *emu)
{
    int err;
    struct snd_kcontrol *kctl;
    struct snd_card *card = emu->card;

    if ((kctl = snd_ctl_new1(&snd_emu10k1x_spdif_mask_control, emu)) == NULL)
        return -ENOMEM;
    if ((err = snd_ctl_add(card, kctl)))
        return err;
    if ((kctl = snd_ctl_new1(&snd_emu10k1x_shared_spdif, emu)) == NULL)
        return -ENOMEM;
    if ((err = snd_ctl_add(card, kctl)))
        return err;
    if ((kctl = snd_ctl_new1(&snd_emu10k1x_spdif_control, emu)) == NULL)
        return -ENOMEM;
    if ((err = snd_ctl_add(card, kctl)))
        return err;

    return 0;
}

#define EMU10K1X_MIDI_MODE_INPUT	(1<<0)
#define EMU10K1X_MIDI_MODE_OUTPUT	(1<<1)

static inline unsigned char mpu401_read(struct emu10k1x *emu, struct emu10k1x_midi *mpu, int idx)
{
    return (unsigned char)snd_emu10k1x_ptr_read(emu, mpu->port + idx, 0);
}

static inline void mpu401_write(struct emu10k1x *emu, struct emu10k1x_midi *mpu, int data, int idx)
{
    snd_emu10k1x_ptr_write(emu, mpu->port + idx, 0, data);
}

#define mpu401_write_data(emu, mpu, data)	mpu401_write(emu, mpu, data, 0)
#define mpu401_write_cmd(emu, mpu, data)	mpu401_write(emu, mpu, data, 1)
#define mpu401_read_data(emu, mpu)		mpu401_read(emu, mpu, 0)
#define mpu401_read_stat(emu, mpu)		mpu401_read(emu, mpu, 1)

#define mpu401_input_avail(emu,mpu)	(!(mpu401_read_stat(emu,mpu) & 0x80))
#define mpu401_output_ready(emu,mpu)	(!(mpu401_read_stat(emu,mpu) & 0x40))

#define MPU401_RESET		0xff
#define MPU401_ENTER_UART	0x3f
#define MPU401_ACK		0xfe

static void mpu401_clear_rx(struct emu10k1x *emu, struct emu10k1x_midi *mpu)
{
    int timeout = 100000;
    for (; timeout > 0 && mpu401_input_avail(emu, mpu); timeout--)
        mpu401_read_data(emu, mpu);
#ifdef CONFIG_SND_DEBUG
    if (timeout <= 0)
        snd_printk(KERN_ERR "cmd: clear rx timeout (status = 0x%x)\n", mpu401_read_stat(emu, mpu));
#endif
}

/*

*/

static void do_emu10k1x_midi_interrupt(struct emu10k1x *emu,
                                       struct emu10k1x_midi *midi, unsigned int status)
{
    unsigned char byte;

    if (midi->rmidi == NULL) {
        snd_emu10k1x_intr_disable(emu, midi->tx_enable | midi->rx_enable);
        return;
    }

    spin_lock(&midi->input_lock);
    if ((status & midi->ipr_rx) && mpu401_input_avail(emu, midi)) {
        if (!(midi->midi_mode & EMU10K1X_MIDI_MODE_INPUT)) {
            mpu401_clear_rx(emu, midi);
        } else {
            byte = mpu401_read_data(emu, midi);
            if (midi->substream_input)
                snd_rawmidi_receive(midi->substream_input, &byte, 1);
        }
    }
    spin_unlock(&midi->input_lock);

    spin_lock(&midi->output_lock);
    if ((status & midi->ipr_tx) && mpu401_output_ready(emu, midi)) {
        if (midi->substream_output &&
            snd_rawmidi_transmit(midi->substream_output, &byte, 1) == 1) {
            mpu401_write_data(emu, midi, byte);
        } else {
            snd_emu10k1x_intr_disable(emu, midi->tx_enable);
        }
    }
    spin_unlock(&midi->output_lock);
}

static void snd_emu10k1x_midi_interrupt(struct emu10k1x *emu, unsigned int status)
{
    do_emu10k1x_midi_interrupt(emu, &emu->midi, status);
}

static int snd_emu10k1x_midi_cmd(struct emu10k1x * emu,
                                 struct emu10k1x_midi *midi, unsigned char cmd, int ack)
{
    unsigned long flags;
    int timeout, ok;

    spin_lock_irqsave(&midi->input_lock, flags);
    mpu401_write_data(emu, midi, 0x00);
    /* mpu401_clear_rx(emu, midi); */

    mpu401_write_cmd(emu, midi, cmd);
    if (ack) {
        ok = 0;
        timeout = 10000;
        while (!ok && timeout-- > 0) {
            if (mpu401_input_avail(emu, midi)) {
                if (mpu401_read_data(emu, midi) == MPU401_ACK)
                    ok = 1;
            }
        }
        if (!ok && mpu401_read_data(emu, midi) == MPU401_ACK)
            ok = 1;
    } else {
        ok = 1;
    }
    spin_unlock_irqrestore(&midi->input_lock, flags);
    if (!ok) {
        snd_printk(KERN_ERR "midi_cmd: 0x%x failed at 0x%lx (status = 0x%x, data = 0x%x)!!!\n",
                   cmd, emu->port,
                   mpu401_read_stat(emu, midi),
                   mpu401_read_data(emu, midi));
        return 1;
    }
    return 0;
}

static int snd_emu10k1x_midi_input_open(struct snd_rawmidi_substream *substream)
{
    struct emu10k1x *emu;
    struct emu10k1x_midi *midi = substream->rmidi->private_data;
    unsigned long flags;

    emu = midi->emu;
    snd_assert(emu, return -ENXIO);
    spin_lock_irqsave(&midi->open_lock, flags);
    midi->midi_mode |= EMU10K1X_MIDI_MODE_INPUT;
    midi->substream_input = substream;
    if (!(midi->midi_mode & EMU10K1X_MIDI_MODE_OUTPUT)) {
        spin_unlock_irqrestore(&midi->open_lock, flags);
        if (snd_emu10k1x_midi_cmd(emu, midi, MPU401_RESET, 1))
            goto error_out;
        if (snd_emu10k1x_midi_cmd(emu, midi, MPU401_ENTER_UART, 1))
            goto error_out;
    } else {
        spin_unlock_irqrestore(&midi->open_lock, flags);
    }
    return 0;

    error_out:
        return -EIO;
}

static int snd_emu10k1x_midi_output_open(struct snd_rawmidi_substream *substream)
{
    struct emu10k1x *emu;
    struct emu10k1x_midi *midi = substream->rmidi->private_data;
    unsigned long flags;

    emu = midi->emu;
    snd_assert(emu, return -ENXIO);
    spin_lock_irqsave(&midi->open_lock, flags);
    midi->midi_mode |= EMU10K1X_MIDI_MODE_OUTPUT;
    midi->substream_output = substream;
    if (!(midi->midi_mode & EMU10K1X_MIDI_MODE_INPUT)) {
        spin_unlock_irqrestore(&midi->open_lock, flags);
        if (snd_emu10k1x_midi_cmd(emu, midi, MPU401_RESET, 1))
            goto error_out;
        if (snd_emu10k1x_midi_cmd(emu, midi, MPU401_ENTER_UART, 1))
            goto error_out;
    } else {
        spin_unlock_irqrestore(&midi->open_lock, flags);
    }
    return 0;

    error_out:
        return -EIO;
}

static int snd_emu10k1x_midi_input_close(struct snd_rawmidi_substream *substream)
{
    struct emu10k1x *emu;
    struct emu10k1x_midi *midi = substream->rmidi->private_data;
    unsigned long flags;
    int err = 0;

    emu = midi->emu;
    snd_assert(emu, return -ENXIO);
    spin_lock_irqsave(&midi->open_lock, flags);
    snd_emu10k1x_intr_disable(emu, midi->rx_enable);
    midi->midi_mode &= ~EMU10K1X_MIDI_MODE_INPUT;
    midi->substream_input = NULL;
    if (!(midi->midi_mode & EMU10K1X_MIDI_MODE_OUTPUT)) {
        spin_unlock_irqrestore(&midi->open_lock, flags);
        err = snd_emu10k1x_midi_cmd(emu, midi, MPU401_RESET, 0);
    } else {
        spin_unlock_irqrestore(&midi->open_lock, flags);
    }
    return err;
}

static int snd_emu10k1x_midi_output_close(struct snd_rawmidi_substream *substream)
{
    struct emu10k1x *emu;
    struct emu10k1x_midi *midi = substream->rmidi->private_data;
    unsigned long flags;
    int err = 0;

    emu = midi->emu;
    snd_assert(emu, return -ENXIO);
    spin_lock_irqsave(&midi->open_lock, flags);
    snd_emu10k1x_intr_disable(emu, midi->tx_enable);
    midi->midi_mode &= ~EMU10K1X_MIDI_MODE_OUTPUT;
    midi->substream_output = NULL;
    if (!(midi->midi_mode & EMU10K1X_MIDI_MODE_INPUT)) {
        spin_unlock_irqrestore(&midi->open_lock, flags);
        err = snd_emu10k1x_midi_cmd(emu, midi, MPU401_RESET, 0);
    } else {
        spin_unlock_irqrestore(&midi->open_lock, flags);
    }
    return err;
}

static void snd_emu10k1x_midi_input_trigger(struct snd_rawmidi_substream *substream, int up)
{
    struct emu10k1x *emu;
    struct emu10k1x_midi *midi = substream->rmidi->private_data;
    emu = midi->emu;
    snd_assert(emu, return);

    if (up)
        snd_emu10k1x_intr_enable(emu, midi->rx_enable);
    else
        snd_emu10k1x_intr_disable(emu, midi->rx_enable);
}

static void snd_emu10k1x_midi_output_trigger(struct snd_rawmidi_substream *substream, int up)
{
    struct emu10k1x *emu;
    struct emu10k1x_midi *midi = substream->rmidi->private_data;
    unsigned long flags;

    emu = midi->emu;
    snd_assert(emu, return);

    if (up) {
        int max = 4;
        unsigned char byte;

        /* try to send some amount of bytes here before interrupts */
        spin_lock_irqsave(&midi->output_lock, flags);
        while (max > 0) {
            if (mpu401_output_ready(emu, midi)) {
                if (!(midi->midi_mode & EMU10K1X_MIDI_MODE_OUTPUT) ||
                    snd_rawmidi_transmit(substream, &byte, 1) != 1) {
                    /* no more data */
                    spin_unlock_irqrestore(&midi->output_lock, flags);
                    return;
                }
                mpu401_write_data(emu, midi, byte);
                max--;
            } else {
                break;
            }
        }
        spin_unlock_irqrestore(&midi->output_lock, flags);
        snd_emu10k1x_intr_enable(emu, midi->tx_enable);
    } else {
        snd_emu10k1x_intr_disable(emu, midi->tx_enable);
    }
}

/*

*/

static struct snd_rawmidi_ops snd_emu10k1x_midi_output =
{
    .open =		snd_emu10k1x_midi_output_open,
    .close =	snd_emu10k1x_midi_output_close,
    .trigger =	snd_emu10k1x_midi_output_trigger,
};

static struct snd_rawmidi_ops snd_emu10k1x_midi_input =
{
    .open =		snd_emu10k1x_midi_input_open,
    .close =	snd_emu10k1x_midi_input_close,
    .trigger =	snd_emu10k1x_midi_input_trigger,
};

static void snd_emu10k1x_midi_free(struct snd_rawmidi *rmidi)
{
    struct emu10k1x_midi *midi = rmidi->private_data;
    midi->interrupt = NULL;
    midi->rmidi = NULL;
}

static int __devinit emu10k1x_midi_init(struct emu10k1x *emu,
                                        struct emu10k1x_midi *midi, int device, char *name)
{
    struct snd_rawmidi *rmidi;
    int err;

    if ((err = snd_rawmidi_new(emu->card, name, device, 1, 1, &rmidi)) < 0)
        return err;
    midi->emu = emu;
    spin_lock_init(&midi->open_lock);
    spin_lock_init(&midi->input_lock);
    spin_lock_init(&midi->output_lock);
    strcpy(rmidi->name, name);
    snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_emu10k1x_midi_output);
    snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_emu10k1x_midi_input);
    rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT |
        SNDRV_RAWMIDI_INFO_INPUT |
        SNDRV_RAWMIDI_INFO_DUPLEX;
    rmidi->private_data = midi;
    rmidi->private_free = snd_emu10k1x_midi_free;
    midi->rmidi = rmidi;
    return 0;
}

static int __devinit snd_emu10k1x_midi(struct emu10k1x *emu)
{
    struct emu10k1x_midi *midi = &emu->midi;
    int err;

    if ((err = emu10k1x_midi_init(emu, midi, 0, "EMU10K1X MPU-401 (UART)")) < 0)
        return err;

    midi->tx_enable = INTE_MIDITXENABLE;
    midi->rx_enable = INTE_MIDIRXENABLE;
    midi->port = MUDATA;
    midi->ipr_tx = IPR_MIDITRANSBUFEMPTY;
    midi->ipr_rx = IPR_MIDIRECVBUFEMPTY;
    midi->interrupt = snd_emu10k1x_midi_interrupt;
    return 0;
}

static int __devinit snd_emu10k1x_probe(struct pci_dev *pci,
                                        const struct pci_device_id *pci_id)
{
    static int dev;
    struct snd_card *card;
    struct emu10k1x *chip;
    int err;

    if (dev >= SNDRV_CARDS)
        return -ENODEV;
    if (!enable[dev]) {
        dev++;
        return -ENOENT;
    }

    card = snd_card_new(index[dev], id[dev], THIS_MODULE, 0);
    if (card == NULL)
        return -ENOMEM;

    if ((err = snd_emu10k1x_create(card, pci, &chip)) < 0) {
        snd_card_free(card);
        return err;
    }

    if ((err = snd_emu10k1x_pcm(chip, 0, NULL)) < 0) {
        snd_card_free(card);
        return err;
    }
    if ((err = snd_emu10k1x_pcm(chip, 1, NULL)) < 0) {
        snd_card_free(card);
        return err;
    }
    if ((err = snd_emu10k1x_pcm(chip, 2, NULL)) < 0) {
        snd_card_free(card);
        return err;
    }

    if ((err = snd_emu10k1x_ac97(chip)) < 0) {
        snd_card_free(card);
        return err;
    }

    if ((err = snd_emu10k1x_mixer(chip)) < 0) {
        snd_card_free(card);
        return err;
    }

    if ((err = snd_emu10k1x_midi(chip)) < 0) {
        snd_card_free(card);
        return err;
    }

    snd_emu10k1x_proc_init(chip);

    strcpy(card->driver, "EMU10K1X");
    strcpy(card->shortname, "Dell Sound Blaster Live!");
    sprintf(card->longname, "%s at 0x%lx irq %i",
            card->shortname, chip->port, chip->irq);

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

    pci_set_drvdata(pci, card);
    dev++;
    return 0;
}

static void __devexit snd_emu10k1x_remove(struct pci_dev *pci)
{
    snd_card_free(pci_get_drvdata(pci));
    pci_set_drvdata(pci, NULL);
}

// PCI IDs
static struct pci_device_id snd_emu10k1x_ids[] = {
    { 0x1102, 0x0006, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0 },	/* Dell OEM version (EMU10K1) */
    { 0, }
};
MODULE_DEVICE_TABLE(pci, snd_emu10k1x_ids);

// pci_driver definition
static struct pci_driver driver = {
    .name = "EMU10K1X",
    .id_table = snd_emu10k1x_ids,
    .probe = snd_emu10k1x_probe,
    .remove = snd_emu10k1x_remove,
};

// initialization of the module
static int __init alsa_card_emu10k1x_init(void)
{
    int err;

    if ((err = pci_register_driver(&driver)) > 0)
        return err;

    return 0;
}

// clean up the module
static void __exit alsa_card_emu10k1x_exit(void)
{
    pci_unregister_driver(&driver);
}

module_init(alsa_card_emu10k1x_init)
module_exit(alsa_card_emu10k1x_exit)
