cx88-alsa.c

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/*
 *
 *  Support for audio capture
 *  PCI function #1 of the cx2388x.
 *
 *    (c) 2007 Trent Piepho <[email protected]>
 *    (c) 2005,2006 Ricardo Cerqueira <[email protected]>
 *    (c) 2005 Mauro Carvalho Chehab <[email protected]>
 *    Based on a dummy cx88 module by Gerd Knorr <[email protected]>
 *    Based on dummy.c by Jaroslav Kysela <[email protected]>
 *
 *  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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/vmalloc.h>
#include <linux/dma-mapping.h>
#include <linux/pci.h>
#include <linux/slab.h>

#include <asm/delay.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/control.h>
#include <sound/initval.h>
#include <sound/tlv.h>
#include <media/wm8775.h>

#include "cx88.h"
#include "cx88-reg.h"

#define dprintk(level,fmt, arg...)  if (debug >= level) \
    printk(KERN_INFO "%s/1: " fmt, chip->core->name , ## arg)

#define dprintk_core(level,fmt, arg...) if (debug >= level) \
    printk(KERN_DEBUG "%s/1: " fmt, chip->core->name , ## arg)

/****************************************************************************
    Data type declarations - Can be moded to a header file later
 ****************************************************************************/

struct cx88_audio_buffer {
    unsigned int               bpl;
    struct btcx_riscmem        risc;
    struct videobuf_dmabuf     dma;
};

struct cx88_audio_dev {
    struct cx88_core           *core;
    struct cx88_dmaqueue       q;

    /* pci i/o */
    struct pci_dev             *pci;

    /* audio controls */
    int                        irq;

    struct snd_card            *card;

    spinlock_t                 reg_lock;
    atomic_t           count;

    unsigned int               dma_size;
    unsigned int               period_size;
    unsigned int               num_periods;

    struct videobuf_dmabuf     *dma_risc;

    struct cx88_audio_buffer   *buf;

    struct snd_pcm_substream   *substream;
};
typedef struct cx88_audio_dev snd_cx88_card_t;



/****************************************************************************
            Module global static vars
 ****************************************************************************/

static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;  /* Index 0-MAX */
static const char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR; /* ID for this card */
static bool enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 1};

module_param_array(enable, bool, NULL, 0444);
MODULE_PARM_DESC(enable, "Enable cx88x soundcard. default enabled.");

module_param_array(index, int, NULL, 0444);
MODULE_PARM_DESC(index, "Index value for cx88x capture interface(s).");


/****************************************************************************
                Module macros
 ****************************************************************************/

MODULE_DESCRIPTION("ALSA driver module for cx2388x based TV cards");
MODULE_AUTHOR("Ricardo Cerqueira");
MODULE_AUTHOR("Mauro Carvalho Chehab <[email protected]>");
MODULE_LICENSE("GPL");
MODULE_VERSION(CX88_VERSION);

MODULE_SUPPORTED_DEVICE("{{Conexant,23881},"
            "{{Conexant,23882},"
            "{{Conexant,23883}");
static unsigned int debug;
module_param(debug,int,0644);
MODULE_PARM_DESC(debug,"enable debug messages");

/****************************************************************************
            Module specific funtions
 ****************************************************************************/

/*
 * BOARD Specific: Sets audio DMA
 */

static int _cx88_start_audio_dma(snd_cx88_card_t *chip)
{
    struct cx88_audio_buffer *buf = chip->buf;
    struct cx88_core *core=chip->core;
    const struct sram_channel *audio_ch = &cx88_sram_channels[SRAM_CH25];

    /* Make sure RISC/FIFO are off before changing FIFO/RISC settings */
    cx_clear(MO_AUD_DMACNTRL, 0x11);

    /* setup fifo + format - out channel */
    cx88_sram_channel_setup(chip->core, audio_ch, buf->bpl, buf->risc.dma);

    /* sets bpl size */
    cx_write(MO_AUDD_LNGTH, buf->bpl);

    /* reset counter */
    cx_write(MO_AUDD_GPCNTRL, GP_COUNT_CONTROL_RESET);
    atomic_set(&chip->count, 0);

    dprintk(1, "Start audio DMA, %d B/line, %d lines/FIFO, %d periods, %d "
        "byte buffer\n", buf->bpl, cx_read(audio_ch->cmds_start + 8)>>1,
        chip->num_periods, buf->bpl * chip->num_periods);

    /* Enables corresponding bits at AUD_INT_STAT */
    cx_write(MO_AUD_INTMSK, AUD_INT_OPC_ERR | AUD_INT_DN_SYNC |
                AUD_INT_DN_RISCI2 | AUD_INT_DN_RISCI1);

    /* Clean any pending interrupt bits already set */
    cx_write(MO_AUD_INTSTAT, ~0);

    /* enable audio irqs */
    cx_set(MO_PCI_INTMSK, chip->core->pci_irqmask | PCI_INT_AUDINT);

    /* start dma */
    cx_set(MO_DEV_CNTRL2, (1<<5)); /* Enables Risc Processor */
    cx_set(MO_AUD_DMACNTRL, 0x11); /* audio downstream FIFO and RISC enable */

    if (debug)
        cx88_sram_channel_dump(chip->core, audio_ch);

    return 0;
}

/*
 * BOARD Specific: Resets audio DMA
 */
static int _cx88_stop_audio_dma(snd_cx88_card_t *chip)
{
    struct cx88_core *core=chip->core;
    dprintk(1, "Stopping audio DMA\n");

    /* stop dma */
    cx_clear(MO_AUD_DMACNTRL, 0x11);

    /* disable irqs */
    cx_clear(MO_PCI_INTMSK, PCI_INT_AUDINT);
    cx_clear(MO_AUD_INTMSK, AUD_INT_OPC_ERR | AUD_INT_DN_SYNC |
                AUD_INT_DN_RISCI2 | AUD_INT_DN_RISCI1);

    if (debug)
        cx88_sram_channel_dump(chip->core, &cx88_sram_channels[SRAM_CH25]);

    return 0;
}

#define MAX_IRQ_LOOP 50

/*
 * BOARD Specific: IRQ dma bits
 */
static const char *cx88_aud_irqs[32] = {
    "dn_risci1", "up_risci1", "rds_dn_risc1", /* 0-2 */
    NULL,                     /* reserved */
    "dn_risci2", "up_risci2", "rds_dn_risc2", /* 4-6 */
    NULL,                     /* reserved */
    "dnf_of", "upf_uf", "rds_dnf_uf",     /* 8-10 */
    NULL,                     /* reserved */
    "dn_sync", "up_sync", "rds_dn_sync",      /* 12-14 */
    NULL,                     /* reserved */
    "opc_err", "par_err", "rip_err",      /* 16-18 */
    "pci_abort", "ber_irq", "mchg_irq"    /* 19-21 */
};

/*
 * BOARD Specific: Threats IRQ audio specific calls
 */
static void cx8801_aud_irq(snd_cx88_card_t *chip)
{
    struct cx88_core *core = chip->core;
    u32 status, mask;

    status = cx_read(MO_AUD_INTSTAT);
    mask   = cx_read(MO_AUD_INTMSK);
    if (0 == (status & mask))
        return;
    cx_write(MO_AUD_INTSTAT, status);
    if (debug > 1  ||  (status & mask & ~0xff))
        cx88_print_irqbits(core->name, "irq aud",
                   cx88_aud_irqs, ARRAY_SIZE(cx88_aud_irqs),
                   status, mask);
    /* risc op code error */
    if (status & AUD_INT_OPC_ERR) {
        printk(KERN_WARNING "%s/1: Audio risc op code error\n",core->name);
        cx_clear(MO_AUD_DMACNTRL, 0x11);
        cx88_sram_channel_dump(core, &cx88_sram_channels[SRAM_CH25]);
    }
    if (status & AUD_INT_DN_SYNC) {
        dprintk(1, "Downstream sync error\n");
        cx_write(MO_AUDD_GPCNTRL, GP_COUNT_CONTROL_RESET);
        return;
    }
    /* risc1 downstream */
    if (status & AUD_INT_DN_RISCI1) {
        atomic_set(&chip->count, cx_read(MO_AUDD_GPCNT));
        snd_pcm_period_elapsed(chip->substream);
    }
    /* FIXME: Any other status should deserve a special handling? */
}

/*
 * BOARD Specific: Handles IRQ calls
 */
static irqreturn_t cx8801_irq(int irq, void *dev_id)
{
    snd_cx88_card_t *chip = dev_id;
    struct cx88_core *core = chip->core;
    u32 status;
    int loop, handled = 0;

    for (loop = 0; loop < MAX_IRQ_LOOP; loop++) {
        status = cx_read(MO_PCI_INTSTAT) &
            (core->pci_irqmask | PCI_INT_AUDINT);
        if (0 == status)
            goto out;
        dprintk(3, "cx8801_irq loop %d/%d, status %x\n",
            loop, MAX_IRQ_LOOP, status);
        handled = 1;
        cx_write(MO_PCI_INTSTAT, status);

        if (status & core->pci_irqmask)
            cx88_core_irq(core, status);
        if (status & PCI_INT_AUDINT)
            cx8801_aud_irq(chip);
    }

    if (MAX_IRQ_LOOP == loop) {
        printk(KERN_ERR
               "%s/1: IRQ loop detected, disabling interrupts\n",
               core->name);
        cx_clear(MO_PCI_INTMSK, PCI_INT_AUDINT);
    }

 out:
    return IRQ_RETVAL(handled);
}


static int dsp_buffer_free(snd_cx88_card_t *chip)
{
    BUG_ON(!chip->dma_size);

    dprintk(2,"Freeing buffer\n");
    videobuf_dma_unmap(&chip->pci->dev, chip->dma_risc);
    videobuf_dma_free(chip->dma_risc);
    btcx_riscmem_free(chip->pci,&chip->buf->risc);
    kfree(chip->buf);

    chip->dma_risc = NULL;
    chip->dma_size = 0;

    return 0;
}

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

/*
 * Digital hardware definition
 */
#define DEFAULT_FIFO_SIZE   4096
static const struct snd_pcm_hardware snd_cx88_digital_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,
    /* Analog audio output will be full of clicks and pops if there
       are not exactly four lines in the SRAM FIFO buffer.  */
    .period_bytes_min = DEFAULT_FIFO_SIZE/4,
    .period_bytes_max = DEFAULT_FIFO_SIZE/4,
    .periods_min = 1,
    .periods_max = 1024,
    .buffer_bytes_max = (1024*1024),
};

/*
 * audio pcm capture open callback
 */
static int snd_cx88_pcm_open(struct snd_pcm_substream *substream)
{
    snd_cx88_card_t *chip = snd_pcm_substream_chip(substream);
    struct snd_pcm_runtime *runtime = substream->runtime;
    int err;

    if (!chip) {
        printk(KERN_ERR "BUG: cx88 can't find device struct."
                " Can't proceed with open\n");
        return -ENODEV;
    }

    err = snd_pcm_hw_constraint_pow2(runtime, 0, SNDRV_PCM_HW_PARAM_PERIODS);
    if (err < 0)
        goto _error;

    chip->substream = substream;

    runtime->hw = snd_cx88_digital_hw;

    if (cx88_sram_channels[SRAM_CH25].fifo_size != DEFAULT_FIFO_SIZE) {
        unsigned int bpl = cx88_sram_channels[SRAM_CH25].fifo_size / 4;
        bpl &= ~7; /* must be multiple of 8 */
        runtime->hw.period_bytes_min = bpl;
        runtime->hw.period_bytes_max = bpl;
    }

    return 0;
_error:
    dprintk(1,"Error opening PCM!\n");
    return err;
}

/*
 * audio close callback
 */
static int snd_cx88_close(struct snd_pcm_substream *substream)
{
    return 0;
}

/*
 * hw_params callback
 */
static int snd_cx88_hw_params(struct snd_pcm_substream * substream,
                  struct snd_pcm_hw_params * hw_params)
{
    snd_cx88_card_t *chip = snd_pcm_substream_chip(substream);
    struct videobuf_dmabuf *dma;

    struct cx88_audio_buffer *buf;
    int ret;

    if (substream->runtime->dma_area) {
        dsp_buffer_free(chip);
        substream->runtime->dma_area = NULL;
    }

    chip->period_size = params_period_bytes(hw_params);
    chip->num_periods = params_periods(hw_params);
    chip->dma_size = chip->period_size * params_periods(hw_params);

    BUG_ON(!chip->dma_size);
    BUG_ON(chip->num_periods & (chip->num_periods-1));

    buf = kzalloc(sizeof(*buf), GFP_KERNEL);
    if (NULL == buf)
        return -ENOMEM;

    buf->bpl = chip->period_size;

    dma = &buf->dma;
    videobuf_dma_init(dma);
    ret = videobuf_dma_init_kernel(dma, PCI_DMA_FROMDEVICE,
            (PAGE_ALIGN(chip->dma_size) >> PAGE_SHIFT));
    if (ret < 0)
        goto error;

    ret = videobuf_dma_map(&chip->pci->dev, dma);
    if (ret < 0)
        goto error;

    ret = cx88_risc_databuffer(chip->pci, &buf->risc, dma->sglist,
                   chip->period_size, chip->num_periods, 1);
    if (ret < 0)
        goto error;

    /* Loop back to start of program */
    buf->risc.jmp[0] = cpu_to_le32(RISC_JUMP|RISC_IRQ1|RISC_CNT_INC);
    buf->risc.jmp[1] = cpu_to_le32(buf->risc.dma);

    chip->buf = buf;
    chip->dma_risc = dma;

    substream->runtime->dma_area = chip->dma_risc->vaddr;
    substream->runtime->dma_bytes = chip->dma_size;
    substream->runtime->dma_addr = 0;
    return 0;

error:
    kfree(buf);
    return ret;
}

/*
 * hw free callback
 */
static int snd_cx88_hw_free(struct snd_pcm_substream * substream)
{

    snd_cx88_card_t *chip = snd_pcm_substream_chip(substream);

    if (substream->runtime->dma_area) {
        dsp_buffer_free(chip);
        substream->runtime->dma_area = NULL;
    }

    return 0;
}

/*
 * prepare callback
 */
static int snd_cx88_prepare(struct snd_pcm_substream *substream)
{
    return 0;
}

/*
 * trigger callback
 */
static int snd_cx88_card_trigger(struct snd_pcm_substream *substream, int cmd)
{
    snd_cx88_card_t *chip = snd_pcm_substream_chip(substream);
    int err;

    /* Local interrupts are already disabled by ALSA */
    spin_lock(&chip->reg_lock);

    switch (cmd) {
    case SNDRV_PCM_TRIGGER_START:
        err=_cx88_start_audio_dma(chip);
        break;
    case SNDRV_PCM_TRIGGER_STOP:
        err=_cx88_stop_audio_dma(chip);
        break;
    default:
        err=-EINVAL;
        break;
    }

    spin_unlock(&chip->reg_lock);

    return err;
}

/*
 * pointer callback
 */
static snd_pcm_uframes_t snd_cx88_pointer(struct snd_pcm_substream *substream)
{
    snd_cx88_card_t *chip = snd_pcm_substream_chip(substream);
    struct snd_pcm_runtime *runtime = substream->runtime;
    u16 count;

    count = atomic_read(&chip->count);

//  dprintk(2, "%s - count %d (+%u), period %d, frame %lu\n", __func__,
//      count, new, count & (runtime->periods-1),
//      runtime->period_size * (count & (runtime->periods-1)));
    return runtime->period_size * (count & (runtime->periods-1));
}

/*
 * page callback (needed for mmap)
 */
static struct page *snd_cx88_page(struct snd_pcm_substream *substream,
                unsigned long offset)
{
    void *pageptr = substream->runtime->dma_area + offset;
    return vmalloc_to_page(pageptr);
}

/*
 * operators
 */
static struct snd_pcm_ops snd_cx88_pcm_ops = {
    .open = snd_cx88_pcm_open,
    .close = snd_cx88_close,
    .ioctl = snd_pcm_lib_ioctl,
    .hw_params = snd_cx88_hw_params,
    .hw_free = snd_cx88_hw_free,
    .prepare = snd_cx88_prepare,
    .trigger = snd_cx88_card_trigger,
    .pointer = snd_cx88_pointer,
    .page = snd_cx88_page,
};

/*
 * create a PCM device
 */
static int __devinit snd_cx88_pcm(snd_cx88_card_t *chip, int device, const char *name)
{
    int err;
    struct snd_pcm *pcm;

    err = snd_pcm_new(chip->card, name, device, 0, 1, &pcm);
    if (err < 0)
        return err;
    pcm->private_data = chip;
    strcpy(pcm->name, name);
    snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_cx88_pcm_ops);

    return 0;
}

/****************************************************************************
                CONTROL INTERFACE
 ****************************************************************************/
static int snd_cx88_volume_info(struct snd_kcontrol *kcontrol,
                struct snd_ctl_elem_info *info)
{
    info->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
    info->count = 2;
    info->value.integer.min = 0;
    info->value.integer.max = 0x3f;

    return 0;
}

static int snd_cx88_volume_get(struct snd_kcontrol *kcontrol,
                   struct snd_ctl_elem_value *value)
{
    snd_cx88_card_t *chip = snd_kcontrol_chip(kcontrol);
    struct cx88_core *core=chip->core;
    int vol = 0x3f - (cx_read(AUD_VOL_CTL) & 0x3f),
        bal = cx_read(AUD_BAL_CTL);

    value->value.integer.value[(bal & 0x40) ? 0 : 1] = vol;
    vol -= (bal & 0x3f);
    value->value.integer.value[(bal & 0x40) ? 1 : 0] = vol < 0 ? 0 : vol;

    return 0;
}

static void snd_cx88_wm8775_volume_put(struct snd_kcontrol *kcontrol,
                   struct snd_ctl_elem_value *value)
{
    snd_cx88_card_t *chip = snd_kcontrol_chip(kcontrol);
    struct cx88_core *core = chip->core;
    int left = value->value.integer.value[0];
    int right = value->value.integer.value[1];
    int v, b;

    /* Pass volume & balance onto any WM8775 */
    if (left >= right) {
        v = left << 10;
        b = left ? (0x8000 * right) / left : 0x8000;
    } else {
        v = right << 10;
        b = right ? 0xffff - (0x8000 * left) / right : 0x8000;
    }
    wm8775_s_ctrl(core, V4L2_CID_AUDIO_VOLUME, v);
    wm8775_s_ctrl(core, V4L2_CID_AUDIO_BALANCE, b);
}

/* OK - TODO: test it */
static int snd_cx88_volume_put(struct snd_kcontrol *kcontrol,
                   struct snd_ctl_elem_value *value)
{
    snd_cx88_card_t *chip = snd_kcontrol_chip(kcontrol);
    struct cx88_core *core=chip->core;
    int left, right, v, b;
    int changed = 0;
    u32 old;

    if (core->board.audio_chip == V4L2_IDENT_WM8775)
        snd_cx88_wm8775_volume_put(kcontrol, value);

    left = value->value.integer.value[0] & 0x3f;
    right = value->value.integer.value[1] & 0x3f;
    b = right - left;
    if (b < 0) {
        v = 0x3f - left;
        b = (-b) | 0x40;
    } else {
        v = 0x3f - right;
    }
    /* Do we really know this will always be called with IRQs on? */
    spin_lock_irq(&chip->reg_lock);
    old = cx_read(AUD_VOL_CTL);
    if (v != (old & 0x3f)) {
        cx_swrite(SHADOW_AUD_VOL_CTL, AUD_VOL_CTL, (old & ~0x3f) | v);
        changed = 1;
    }
    if ((cx_read(AUD_BAL_CTL) & 0x7f) != b) {
        cx_write(AUD_BAL_CTL, b);
        changed = 1;
    }
    spin_unlock_irq(&chip->reg_lock);

    return changed;
}

static const DECLARE_TLV_DB_SCALE(snd_cx88_db_scale, -6300, 100, 0);

static const struct snd_kcontrol_new snd_cx88_volume = {
    .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
    .access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
          SNDRV_CTL_ELEM_ACCESS_TLV_READ,
    .name = "Analog-TV Volume",
    .info = snd_cx88_volume_info,
    .get = snd_cx88_volume_get,
    .put = snd_cx88_volume_put,
    .tlv.p = snd_cx88_db_scale,
};

static int snd_cx88_switch_get(struct snd_kcontrol *kcontrol,
                   struct snd_ctl_elem_value *value)
{
    snd_cx88_card_t *chip = snd_kcontrol_chip(kcontrol);
    struct cx88_core *core = chip->core;
    u32 bit = kcontrol->private_value;

    value->value.integer.value[0] = !(cx_read(AUD_VOL_CTL) & bit);
    return 0;
}

static int snd_cx88_switch_put(struct snd_kcontrol *kcontrol,
                       struct snd_ctl_elem_value *value)
{
    snd_cx88_card_t *chip = snd_kcontrol_chip(kcontrol);
    struct cx88_core *core = chip->core;
    u32 bit = kcontrol->private_value;
    int ret = 0;
    u32 vol;

    spin_lock_irq(&chip->reg_lock);
    vol = cx_read(AUD_VOL_CTL);
    if (value->value.integer.value[0] != !(vol & bit)) {
        vol ^= bit;
        cx_swrite(SHADOW_AUD_VOL_CTL, AUD_VOL_CTL, vol);
        /* Pass mute onto any WM8775 */
        if ((core->board.audio_chip == V4L2_IDENT_WM8775) &&
            ((1<<6) == bit))
            wm8775_s_ctrl(core, V4L2_CID_AUDIO_MUTE, 0 != (vol & bit));
        ret = 1;
    }
    spin_unlock_irq(&chip->reg_lock);
    return ret;
}

static const struct snd_kcontrol_new snd_cx88_dac_switch = {
    .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
    .name = "Audio-Out Switch",
    .info = snd_ctl_boolean_mono_info,
    .get = snd_cx88_switch_get,
    .put = snd_cx88_switch_put,
    .private_value = (1<<8),
};

static const struct snd_kcontrol_new snd_cx88_source_switch = {
    .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
    .name = "Analog-TV Switch",
    .info = snd_ctl_boolean_mono_info,
    .get = snd_cx88_switch_get,
    .put = snd_cx88_switch_put,
    .private_value = (1<<6),
};

static int snd_cx88_alc_get(struct snd_kcontrol *kcontrol,
                   struct snd_ctl_elem_value *value)
{
    snd_cx88_card_t *chip = snd_kcontrol_chip(kcontrol);
    struct cx88_core *core = chip->core;
    s32 val;

    val = wm8775_g_ctrl(core, V4L2_CID_AUDIO_LOUDNESS);
    value->value.integer.value[0] = val ? 1 : 0;
    return 0;
}

static int snd_cx88_alc_put(struct snd_kcontrol *kcontrol,
                       struct snd_ctl_elem_value *value)
{
    snd_cx88_card_t *chip = snd_kcontrol_chip(kcontrol);
    struct cx88_core *core = chip->core;
    struct v4l2_control client_ctl;

    memset(&client_ctl, 0, sizeof(client_ctl));
    client_ctl.value = 0 != value->value.integer.value[0];
    client_ctl.id = V4L2_CID_AUDIO_LOUDNESS;
    call_hw(core, WM8775_GID, core, s_ctrl, &client_ctl);

    return 0;
}

static struct snd_kcontrol_new snd_cx88_alc_switch = {
    .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
    .name = "Line-In ALC Switch",
    .info = snd_ctl_boolean_mono_info,
    .get = snd_cx88_alc_get,
    .put = snd_cx88_alc_put,
};

/****************************************************************************
            Basic Flow for Sound Devices
 ****************************************************************************/

/*
 * PCI ID Table - 14f1:8801 and 14f1:8811 means function 1: Audio
 * Only boards with eeprom and byte 1 at eeprom=1 have it
 */

static const struct pci_device_id cx88_audio_pci_tbl[] __devinitdata = {
    {0x14f1,0x8801,PCI_ANY_ID,PCI_ANY_ID,0,0,0},
    {0x14f1,0x8811,PCI_ANY_ID,PCI_ANY_ID,0,0,0},
    {0, }
};
MODULE_DEVICE_TABLE(pci, cx88_audio_pci_tbl);

/*
 * Chip-specific destructor
 */

static int snd_cx88_free(snd_cx88_card_t *chip)
{

    if (chip->irq >= 0)
        free_irq(chip->irq, chip);

    cx88_core_put(chip->core,chip->pci);

    pci_disable_device(chip->pci);
    return 0;
}

/*
 * Component Destructor
 */
static void snd_cx88_dev_free(struct snd_card * card)
{
    snd_cx88_card_t *chip = card->private_data;

    snd_cx88_free(chip);
}


/*
 * Alsa Constructor - Component probe
 */

static int devno;
static int __devinit snd_cx88_create(struct snd_card *card,
                     struct pci_dev *pci,
                     snd_cx88_card_t **rchip,
                     struct cx88_core **core_ptr)
{
    snd_cx88_card_t   *chip;
    struct cx88_core  *core;
    int               err;
    unsigned char     pci_lat;

    *rchip = NULL;

    err = pci_enable_device(pci);
    if (err < 0)
        return err;

    pci_set_master(pci);

    chip = card->private_data;

    core = cx88_core_get(pci);
    if (NULL == core) {
        err = -EINVAL;
        return err;
    }

    if (!pci_dma_supported(pci,DMA_BIT_MASK(32))) {
        dprintk(0, "%s/1: Oops: no 32bit PCI DMA ???\n",core->name);
        err = -EIO;
        cx88_core_put(core, pci);
        return err;
    }


    /* pci init */
    chip->card = card;
    chip->pci = pci;
    chip->irq = -1;
    spin_lock_init(&chip->reg_lock);

    chip->core = core;

    /* get irq */
    err = request_irq(chip->pci->irq, cx8801_irq,
              IRQF_SHARED | IRQF_DISABLED, chip->core->name, chip);
    if (err < 0) {
        dprintk(0, "%s: can't get IRQ %d\n",
               chip->core->name, chip->pci->irq);
        return err;
    }

    /* print pci info */
    pci_read_config_byte(pci, PCI_LATENCY_TIMER, &pci_lat);

    dprintk(1,"ALSA %s/%i: found at %s, rev: %d, irq: %d, "
           "latency: %d, mmio: 0x%llx\n", core->name, devno,
           pci_name(pci), pci->revision, pci->irq,
           pci_lat, (unsigned long long)pci_resource_start(pci,0));

    chip->irq = pci->irq;
    synchronize_irq(chip->irq);

    snd_card_set_dev(card, &pci->dev);

    *rchip = chip;
    *core_ptr = core;

    return 0;
}

static int __devinit cx88_audio_initdev(struct pci_dev *pci,
                    const struct pci_device_id *pci_id)
{
    struct snd_card  *card;
    snd_cx88_card_t  *chip;
    struct cx88_core *core = NULL;
    int              err;

    if (devno >= SNDRV_CARDS)
        return (-ENODEV);

    if (!enable[devno]) {
        ++devno;
        return (-ENOENT);
    }

    err = snd_card_create(index[devno], id[devno], THIS_MODULE,
                  sizeof(snd_cx88_card_t), &card);
    if (err < 0)
        return err;

    card->private_free = snd_cx88_dev_free;

    err = snd_cx88_create(card, pci, &chip, &core);
    if (err < 0)
        goto error;

    err = snd_cx88_pcm(chip, 0, "CX88 Digital");
    if (err < 0)
        goto error;

    err = snd_ctl_add(card, snd_ctl_new1(&snd_cx88_volume, chip));
    if (err < 0)
        goto error;
    err = snd_ctl_add(card, snd_ctl_new1(&snd_cx88_dac_switch, chip));
    if (err < 0)
        goto error;
    err = snd_ctl_add(card, snd_ctl_new1(&snd_cx88_source_switch, chip));
    if (err < 0)
        goto error;

    /* If there's a wm8775 then add a Line-In ALC switch */
    if (core->board.audio_chip == V4L2_IDENT_WM8775)
        snd_ctl_add(card, snd_ctl_new1(&snd_cx88_alc_switch, chip));

    strcpy (card->driver, "CX88x");
    sprintf(card->shortname, "Conexant CX%x", pci->device);
    sprintf(card->longname, "%s at %#llx",
        card->shortname,(unsigned long long)pci_resource_start(pci, 0));
    strcpy (card->mixername, "CX88");

    dprintk (0, "%s/%i: ALSA support for cx2388x boards\n",
           card->driver,devno);

    err = snd_card_register(card);
    if (err < 0)
        goto error;
    pci_set_drvdata(pci,card);

    devno++;
    return 0;

error:
    snd_card_free(card);
    return err;
}
/*
 * ALSA destructor
 */
static void __devexit cx88_audio_finidev(struct pci_dev *pci)
{
    struct cx88_audio_dev *card = pci_get_drvdata(pci);

    snd_card_free((void *)card);

    pci_set_drvdata(pci, NULL);

    devno--;
}

/*
 * PCI driver definition
 */

static struct pci_driver cx88_audio_pci_driver = {
    .name     = "cx88_audio",
    .id_table = cx88_audio_pci_tbl,
    .probe    = cx88_audio_initdev,
    .remove   = __devexit_p(cx88_audio_finidev),
};

/****************************************************************************
                LINUX MODULE INIT
 ****************************************************************************/

/*
 * module init
 */
static int __init cx88_audio_init(void)
{
    printk(KERN_INFO "cx2388x alsa driver version %s loaded\n",
           CX88_VERSION);
    return pci_register_driver(&cx88_audio_pci_driver);
}

/*
 * module remove
 */
static void __exit cx88_audio_fini(void)
{
    pci_unregister_driver(&cx88_audio_pci_driver);
}

module_init(cx88_audio_init);
module_exit(cx88_audio_fini);