saa7134-alsa.c

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/*
 *   SAA713x ALSA support for V4L
 *
 *   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, version 2
 *
 *   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 <linux/init.h>
#include <linux/slab.h>
#include <linux/time.h>
#include <linux/wait.h>
#include <linux/module.h>
#include <sound/core.h>
#include <sound/control.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/initval.h>
#include <linux/interrupt.h>

#include "saa7134.h"
#include "saa7134-reg.h"

static unsigned int debug;
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug,"enable debug messages [alsa]");

/*
 * Configuration macros
 */

/* defaults */
#define MIXER_ADDR_UNSELECTED   -1
#define MIXER_ADDR_TVTUNER  0
#define MIXER_ADDR_LINE1    1
#define MIXER_ADDR_LINE2    2
#define MIXER_ADDR_LAST     2


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

module_param_array(index, int, NULL, 0444);
module_param_array(enable, int, NULL, 0444);
MODULE_PARM_DESC(index, "Index value for SAA7134 capture interface(s).");
MODULE_PARM_DESC(enable, "Enable (or not) the SAA7134 capture interface(s).");

#define dprintk(fmt, arg...)    if (debug) \
    printk(KERN_DEBUG "%s/alsa: " fmt, dev->name , ##arg)



/*
 * Main chip structure
 */

typedef struct snd_card_saa7134 {
    struct snd_card *card;
    spinlock_t mixer_lock;
    int mixer_volume[MIXER_ADDR_LAST+1][2];
    int capture_source_addr;
    int capture_source[2];
    struct snd_kcontrol *capture_ctl[MIXER_ADDR_LAST+1];
    struct pci_dev *pci;
    struct saa7134_dev *dev;

    unsigned long iobase;
    s16 irq;
    u16 mute_was_on;

    spinlock_t lock;
} snd_card_saa7134_t;


/*
 * PCM structure
 */

typedef struct snd_card_saa7134_pcm {
    struct saa7134_dev *dev;

    spinlock_t lock;

    struct snd_pcm_substream *substream;
} snd_card_saa7134_pcm_t;

static struct snd_card *snd_saa7134_cards[SNDRV_CARDS];


/*
 * saa7134 DMA audio stop
 *
 *   Called when the capture device is released or the buffer overflows
 *
 *   - Copied verbatim from saa7134-oss's dsp_dma_stop.
 *
 */

static void saa7134_dma_stop(struct saa7134_dev *dev)
{
    dev->dmasound.dma_blk     = -1;
    dev->dmasound.dma_running = 0;
    saa7134_set_dmabits(dev);
}

/*
 * saa7134 DMA audio start
 *
 *   Called when preparing the capture device for use
 *
 *   - Copied verbatim from saa7134-oss's dsp_dma_start.
 *
 */

static void saa7134_dma_start(struct saa7134_dev *dev)
{
    dev->dmasound.dma_blk     = 0;
    dev->dmasound.dma_running = 1;
    saa7134_set_dmabits(dev);
}

/*
 * saa7134 audio DMA IRQ handler
 *
 *   Called whenever we get an SAA7134_IRQ_REPORT_DONE_RA3 interrupt
 *   Handles shifting between the 2 buffers, manages the read counters,
 *  and notifies ALSA when periods elapse
 *
 *   - Mostly copied from saa7134-oss's saa7134_irq_oss_done.
 *
 */

static void saa7134_irq_alsa_done(struct saa7134_dev *dev,
                  unsigned long status)
{
    int next_blk, reg = 0;

    spin_lock(&dev->slock);
    if (UNSET == dev->dmasound.dma_blk) {
        dprintk("irq: recording stopped\n");
        goto done;
    }
    if (0 != (status & 0x0f000000))
        dprintk("irq: lost %ld\n", (status >> 24) & 0x0f);
    if (0 == (status & 0x10000000)) {
        /* odd */
        if (0 == (dev->dmasound.dma_blk & 0x01))
            reg = SAA7134_RS_BA1(6);
    } else {
        /* even */
        if (1 == (dev->dmasound.dma_blk & 0x01))
            reg = SAA7134_RS_BA2(6);
    }
    if (0 == reg) {
        dprintk("irq: field oops [%s]\n",
            (status & 0x10000000) ? "even" : "odd");
        goto done;
    }

    if (dev->dmasound.read_count >= dev->dmasound.blksize * (dev->dmasound.blocks-2)) {
        dprintk("irq: overrun [full=%d/%d] - Blocks in %d\n",dev->dmasound.read_count,
            dev->dmasound.bufsize, dev->dmasound.blocks);
        spin_unlock(&dev->slock);
        snd_pcm_stop(dev->dmasound.substream,SNDRV_PCM_STATE_XRUN);
        return;
    }

    /* next block addr */
    next_blk = (dev->dmasound.dma_blk + 2) % dev->dmasound.blocks;
    saa_writel(reg,next_blk * dev->dmasound.blksize);
    if (debug > 2)
        dprintk("irq: ok, %s, next_blk=%d, addr=%x, blocks=%u, size=%u, read=%u\n",
            (status & 0x10000000) ? "even" : "odd ", next_blk,
            next_blk * dev->dmasound.blksize, dev->dmasound.blocks, dev->dmasound.blksize, dev->dmasound.read_count);

    /* update status & wake waiting readers */
    dev->dmasound.dma_blk = (dev->dmasound.dma_blk + 1) % dev->dmasound.blocks;
    dev->dmasound.read_count += dev->dmasound.blksize;

    dev->dmasound.recording_on = reg;

    if (dev->dmasound.read_count >= snd_pcm_lib_period_bytes(dev->dmasound.substream)) {
        spin_unlock(&dev->slock);
        snd_pcm_period_elapsed(dev->dmasound.substream);
        spin_lock(&dev->slock);
    }

 done:
    spin_unlock(&dev->slock);

}

/*
 * IRQ request handler
 *
 *   Runs along with saa7134's IRQ handler, discards anything that isn't
 *   DMA sound
 *
 */

static irqreturn_t saa7134_alsa_irq(int irq, void *dev_id)
{
    struct saa7134_dmasound *dmasound = dev_id;
    struct saa7134_dev *dev = dmasound->priv_data;

    unsigned long report, status;
    int loop, handled = 0;

    for (loop = 0; loop < 10; loop++) {
        report = saa_readl(SAA7134_IRQ_REPORT);
        status = saa_readl(SAA7134_IRQ_STATUS);

        if (report & SAA7134_IRQ_REPORT_DONE_RA3) {
            handled = 1;
            saa_writel(SAA7134_IRQ_REPORT,
                   SAA7134_IRQ_REPORT_DONE_RA3);
            saa7134_irq_alsa_done(dev, status);
        } else {
            goto out;
        }
    }

    if (loop == 10) {
        dprintk("error! looping IRQ!");
    }

out:
    return IRQ_RETVAL(handled);
}

/*
 * ALSA capture trigger
 *
 *   - One of the ALSA capture callbacks.
 *
 *   Called whenever a capture is started or stopped. Must be defined,
 *   but there's nothing we want to do here
 *
 */

static int snd_card_saa7134_capture_trigger(struct snd_pcm_substream * substream,
                      int cmd)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    snd_card_saa7134_pcm_t *pcm = runtime->private_data;
    struct saa7134_dev *dev=pcm->dev;
    int err = 0;

    spin_lock(&dev->slock);
    if (cmd == SNDRV_PCM_TRIGGER_START) {
        /* start dma */
        saa7134_dma_start(dev);
    } else if (cmd == SNDRV_PCM_TRIGGER_STOP) {
        /* stop dma */
        saa7134_dma_stop(dev);
    } else {
        err = -EINVAL;
    }
    spin_unlock(&dev->slock);

    return err;
}

/*
 * DMA buffer initialization
 *
 *   Uses V4L functions to initialize the DMA. Shouldn't be necessary in
 *  ALSA, but I was unable to use ALSA's own DMA, and had to force the
 *  usage of V4L's
 *
 *   - Copied verbatim from saa7134-oss.
 *
 */

static int dsp_buffer_init(struct saa7134_dev *dev)
{
    int err;

    BUG_ON(!dev->dmasound.bufsize);

    videobuf_dma_init(&dev->dmasound.dma);
    err = videobuf_dma_init_kernel(&dev->dmasound.dma, PCI_DMA_FROMDEVICE,
                       (dev->dmasound.bufsize + PAGE_SIZE) >> PAGE_SHIFT);
    if (0 != err)
        return err;
    return 0;
}

/*
 * DMA buffer release
 *
 *   Called after closing the device, during snd_card_saa7134_capture_close
 *
 */

static int dsp_buffer_free(struct saa7134_dev *dev)
{
    BUG_ON(!dev->dmasound.blksize);

    videobuf_dma_free(&dev->dmasound.dma);

    dev->dmasound.blocks  = 0;
    dev->dmasound.blksize = 0;
    dev->dmasound.bufsize = 0;

    return 0;
}

/*
 * Setting the capture source and updating the ALSA controls
 */
static int snd_saa7134_capsrc_set(struct snd_kcontrol *kcontrol,
                  int left, int right, bool force_notify)
{
    snd_card_saa7134_t *chip = snd_kcontrol_chip(kcontrol);
    int change = 0, addr = kcontrol->private_value;
    int active, old_addr;
    u32 anabar, xbarin;
    int analog_io, rate;
    struct saa7134_dev *dev;

    dev = chip->dev;

    spin_lock_irq(&chip->mixer_lock);

    active = left != 0 || right != 0;
    old_addr = chip->capture_source_addr;

    /* The active capture source cannot be deactivated */
    if (active) {
        change = old_addr != addr ||
             chip->capture_source[0] != left ||
             chip->capture_source[1] != right;

        chip->capture_source[0] = left;
        chip->capture_source[1] = right;
        chip->capture_source_addr = addr;
        dev->dmasound.input = addr;
    }
    spin_unlock_irq(&chip->mixer_lock);

    if (change) {
        switch (dev->pci->device) {

        case PCI_DEVICE_ID_PHILIPS_SAA7134:
            switch (addr) {
            case MIXER_ADDR_TVTUNER:
                saa_andorb(SAA7134_AUDIO_FORMAT_CTRL,
                       0xc0, 0xc0);
                saa_andorb(SAA7134_SIF_SAMPLE_FREQ,
                       0x03, 0x00);
                break;
            case MIXER_ADDR_LINE1:
            case MIXER_ADDR_LINE2:
                analog_io = (MIXER_ADDR_LINE1 == addr) ?
                         0x00 : 0x08;
                rate = (32000 == dev->dmasound.rate) ?
                    0x01 : 0x03;
                saa_andorb(SAA7134_ANALOG_IO_SELECT,
                       0x08, analog_io);
                saa_andorb(SAA7134_AUDIO_FORMAT_CTRL,
                       0xc0, 0x80);
                saa_andorb(SAA7134_SIF_SAMPLE_FREQ,
                       0x03, rate);
                break;
            }

            break;
        case PCI_DEVICE_ID_PHILIPS_SAA7133:
        case PCI_DEVICE_ID_PHILIPS_SAA7135:
            xbarin = 0x03; /* adc */
            anabar = 0;
            switch (addr) {
            case MIXER_ADDR_TVTUNER:
                xbarin = 0; /* Demodulator */
                anabar = 2; /* DACs */
                break;
            case MIXER_ADDR_LINE1:
                anabar = 0;  /* aux1, aux1 */
                break;
            case MIXER_ADDR_LINE2:
                anabar = 9;  /* aux2, aux2 */
                break;
            }

            /* output xbar always main channel */
            saa_dsp_writel(dev, SAA7133_DIGITAL_OUTPUT_SEL1,
                       0xbbbb10);

            if (left || right) {
                /* We've got data, turn the input on */
                saa_dsp_writel(dev, SAA7133_DIGITAL_INPUT_XBAR1,
                           xbarin);
                saa_writel(SAA7133_ANALOG_IO_SELECT, anabar);
            } else {
                saa_dsp_writel(dev, SAA7133_DIGITAL_INPUT_XBAR1,
                           0);
                saa_writel(SAA7133_ANALOG_IO_SELECT, 0);
            }
            break;
        }
    }

    if (change) {
        if (force_notify)
            snd_ctl_notify(chip->card,
                       SNDRV_CTL_EVENT_MASK_VALUE,
                       &chip->capture_ctl[addr]->id);

        if (old_addr != MIXER_ADDR_UNSELECTED && old_addr != addr)
            snd_ctl_notify(chip->card,
                       SNDRV_CTL_EVENT_MASK_VALUE,
                       &chip->capture_ctl[old_addr]->id);
    }

    return change;
}

/*
 * ALSA PCM preparation
 *
 *   - One of the ALSA capture callbacks.
 *
 *   Called right after the capture device is opened, this function configures
 *  the buffer using the previously defined functions, allocates the memory,
 *  sets up the hardware registers, and then starts the DMA. When this function
 *  returns, the audio should be flowing.
 *
 */

static int snd_card_saa7134_capture_prepare(struct snd_pcm_substream * substream)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    int bswap, sign;
    u32 fmt, control;
    snd_card_saa7134_t *saa7134 = snd_pcm_substream_chip(substream);
    struct saa7134_dev *dev;
    snd_card_saa7134_pcm_t *pcm = runtime->private_data;

    pcm->dev->dmasound.substream = substream;

    dev = saa7134->dev;

    if (snd_pcm_format_width(runtime->format) == 8)
        fmt = 0x00;
    else
        fmt = 0x01;

    if (snd_pcm_format_signed(runtime->format))
        sign = 1;
    else
        sign = 0;

    if (snd_pcm_format_big_endian(runtime->format))
        bswap = 1;
    else
        bswap = 0;

    switch (dev->pci->device) {
      case PCI_DEVICE_ID_PHILIPS_SAA7134:
        if (1 == runtime->channels)
            fmt |= (1 << 3);
        if (2 == runtime->channels)
            fmt |= (3 << 3);
        if (sign)
            fmt |= 0x04;

        fmt |= (MIXER_ADDR_TVTUNER == dev->dmasound.input) ? 0xc0 : 0x80;
        saa_writeb(SAA7134_NUM_SAMPLES0, ((dev->dmasound.blksize - 1) & 0x0000ff));
        saa_writeb(SAA7134_NUM_SAMPLES1, ((dev->dmasound.blksize - 1) & 0x00ff00) >>  8);
        saa_writeb(SAA7134_NUM_SAMPLES2, ((dev->dmasound.blksize - 1) & 0xff0000) >> 16);
        saa_writeb(SAA7134_AUDIO_FORMAT_CTRL, fmt);

        break;
      case PCI_DEVICE_ID_PHILIPS_SAA7133:
      case PCI_DEVICE_ID_PHILIPS_SAA7135:
        if (1 == runtime->channels)
            fmt |= (1 << 4);
        if (2 == runtime->channels)
            fmt |= (2 << 4);
        if (!sign)
            fmt |= 0x04;
        saa_writel(SAA7133_NUM_SAMPLES, dev->dmasound.blksize -1);
        saa_writel(SAA7133_AUDIO_CHANNEL, 0x543210 | (fmt << 24));
        break;
    }

    dprintk("rec_start: afmt=%d ch=%d  =>  fmt=0x%x swap=%c\n",
        runtime->format, runtime->channels, fmt,
        bswap ? 'b' : '-');
    /* dma: setup channel 6 (= AUDIO) */
    control = SAA7134_RS_CONTROL_BURST_16 |
        SAA7134_RS_CONTROL_ME |
        (dev->dmasound.pt.dma >> 12);
    if (bswap)
        control |= SAA7134_RS_CONTROL_BSWAP;

    saa_writel(SAA7134_RS_BA1(6),0);
    saa_writel(SAA7134_RS_BA2(6),dev->dmasound.blksize);
    saa_writel(SAA7134_RS_PITCH(6),0);
    saa_writel(SAA7134_RS_CONTROL(6),control);

    dev->dmasound.rate = runtime->rate;

    /* Setup and update the card/ALSA controls */
    snd_saa7134_capsrc_set(saa7134->capture_ctl[dev->dmasound.input], 1, 1,
                   true);

    return 0;

}

/*
 * ALSA pointer fetching
 *
 *   - One of the ALSA capture callbacks.
 *
 *   Called whenever a period elapses, it must return the current hardware
 *  position of the buffer.
 *   Also resets the read counter used to prevent overruns
 *
 */

static snd_pcm_uframes_t
snd_card_saa7134_capture_pointer(struct snd_pcm_substream * substream)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    snd_card_saa7134_pcm_t *pcm = runtime->private_data;
    struct saa7134_dev *dev=pcm->dev;

    if (dev->dmasound.read_count) {
        dev->dmasound.read_count  -= snd_pcm_lib_period_bytes(substream);
        dev->dmasound.read_offset += snd_pcm_lib_period_bytes(substream);
        if (dev->dmasound.read_offset == dev->dmasound.bufsize)
            dev->dmasound.read_offset = 0;
    }

    return bytes_to_frames(runtime, dev->dmasound.read_offset);
}

/*
 * ALSA hardware capabilities definition
 *
 *  Report only 32kHz for ALSA:
 *
 *  - SAA7133/35 uses DDEP (DemDec Easy Programming mode), which works in 32kHz
 *    only
 *  - SAA7134 for TV mode uses DemDec mode (32kHz)
 *  - Radio works in 32kHz only
 *  - When recording 48kHz from Line1/Line2, switching of capture source to TV
 *    means
 *    switching to 32kHz without any frequency translation
 */

static struct snd_pcm_hardware snd_card_saa7134_capture =
{
    .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 | \
                SNDRV_PCM_FMTBIT_S16_BE | \
                SNDRV_PCM_FMTBIT_S8 | \
                SNDRV_PCM_FMTBIT_U8 | \
                SNDRV_PCM_FMTBIT_U16_LE | \
                SNDRV_PCM_FMTBIT_U16_BE,
    .rates =        SNDRV_PCM_RATE_32000,
    .rate_min =     32000,
    .rate_max =     32000,
    .channels_min =     1,
    .channels_max =     2,
    .buffer_bytes_max = (256*1024),
    .period_bytes_min = 64,
    .period_bytes_max = (256*1024),
    .periods_min =      4,
    .periods_max =      1024,
};

static void snd_card_saa7134_runtime_free(struct snd_pcm_runtime *runtime)
{
    snd_card_saa7134_pcm_t *pcm = runtime->private_data;

    kfree(pcm);
}


/*
 * ALSA hardware params
 *
 *   - One of the ALSA capture callbacks.
 *
 *   Called on initialization, right before the PCM preparation
 *
 */

static int snd_card_saa7134_hw_params(struct snd_pcm_substream * substream,
                      struct snd_pcm_hw_params * hw_params)
{
    snd_card_saa7134_t *saa7134 = snd_pcm_substream_chip(substream);
    struct saa7134_dev *dev;
    unsigned int period_size, periods;
    int err;

    period_size = params_period_bytes(hw_params);
    periods = params_periods(hw_params);

    if (period_size < 0x100 || period_size > 0x10000)
        return -EINVAL;
    if (periods < 4)
        return -EINVAL;
    if (period_size * periods > 1024 * 1024)
        return -EINVAL;

    dev = saa7134->dev;

    if (dev->dmasound.blocks == periods &&
        dev->dmasound.blksize == period_size)
        return 0;

    /* release the old buffer */
    if (substream->runtime->dma_area) {
        saa7134_pgtable_free(dev->pci, &dev->dmasound.pt);
        videobuf_dma_unmap(&dev->pci->dev, &dev->dmasound.dma);
        dsp_buffer_free(dev);
        substream->runtime->dma_area = NULL;
    }
    dev->dmasound.blocks  = periods;
    dev->dmasound.blksize = period_size;
    dev->dmasound.bufsize = period_size * periods;

    err = dsp_buffer_init(dev);
    if (0 != err) {
        dev->dmasound.blocks  = 0;
        dev->dmasound.blksize = 0;
        dev->dmasound.bufsize = 0;
        return err;
    }

    if (0 != (err = videobuf_dma_map(&dev->pci->dev, &dev->dmasound.dma))) {
        dsp_buffer_free(dev);
        return err;
    }
    if (0 != (err = saa7134_pgtable_alloc(dev->pci,&dev->dmasound.pt))) {
        videobuf_dma_unmap(&dev->pci->dev, &dev->dmasound.dma);
        dsp_buffer_free(dev);
        return err;
    }
    if (0 != (err = saa7134_pgtable_build(dev->pci,&dev->dmasound.pt,
                        dev->dmasound.dma.sglist,
                        dev->dmasound.dma.sglen,
                        0))) {
        saa7134_pgtable_free(dev->pci, &dev->dmasound.pt);
        videobuf_dma_unmap(&dev->pci->dev, &dev->dmasound.dma);
        dsp_buffer_free(dev);
        return err;
    }

    /* I should be able to use runtime->dma_addr in the control
       byte, but it doesn't work. So I allocate the DMA using the
       V4L functions, and force ALSA to use that as the DMA area */

    substream->runtime->dma_area = dev->dmasound.dma.vaddr;
    substream->runtime->dma_bytes = dev->dmasound.bufsize;
    substream->runtime->dma_addr = 0;

    return 0;

}

/*
 * ALSA hardware release
 *
 *   - One of the ALSA capture callbacks.
 *
 *   Called after closing the device, but before snd_card_saa7134_capture_close
 *   It stops the DMA audio and releases the buffers.
 *
 */

static int snd_card_saa7134_hw_free(struct snd_pcm_substream * substream)
{
    snd_card_saa7134_t *saa7134 = snd_pcm_substream_chip(substream);
    struct saa7134_dev *dev;

    dev = saa7134->dev;

    if (substream->runtime->dma_area) {
        saa7134_pgtable_free(dev->pci, &dev->dmasound.pt);
        videobuf_dma_unmap(&dev->pci->dev, &dev->dmasound.dma);
        dsp_buffer_free(dev);
        substream->runtime->dma_area = NULL;
    }

    return 0;
}

/*
 * ALSA capture finish
 *
 *   - One of the ALSA capture callbacks.
 *
 *   Called after closing the device.
 *
 */

static int snd_card_saa7134_capture_close(struct snd_pcm_substream * substream)
{
    snd_card_saa7134_t *saa7134 = snd_pcm_substream_chip(substream);
    struct saa7134_dev *dev = saa7134->dev;

    if (saa7134->mute_was_on) {
        dev->ctl_mute = 1;
        saa7134_tvaudio_setmute(dev);
    }
    return 0;
}

/*
 * ALSA capture start
 *
 *   - One of the ALSA capture callbacks.
 *
 *   Called when opening the device. It creates and populates the PCM
 *  structure
 *
 */

static int snd_card_saa7134_capture_open(struct snd_pcm_substream * substream)
{
    struct snd_pcm_runtime *runtime = substream->runtime;
    snd_card_saa7134_pcm_t *pcm;
    snd_card_saa7134_t *saa7134 = snd_pcm_substream_chip(substream);
    struct saa7134_dev *dev;
    int amux, err;

    if (!saa7134) {
        printk(KERN_ERR "BUG: saa7134 can't find device struct."
                " Can't proceed with open\n");
        return -ENODEV;
    }
    dev = saa7134->dev;
    mutex_lock(&dev->dmasound.lock);

    dev->dmasound.read_count  = 0;
    dev->dmasound.read_offset = 0;

    amux = dev->input->amux;
    if ((amux < 1) || (amux > 3))
        amux = 1;
    dev->dmasound.input  =  amux - 1;

    mutex_unlock(&dev->dmasound.lock);

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

    pcm->dev=saa7134->dev;

    spin_lock_init(&pcm->lock);

    pcm->substream = substream;
    runtime->private_data = pcm;
    runtime->private_free = snd_card_saa7134_runtime_free;
    runtime->hw = snd_card_saa7134_capture;

    if (dev->ctl_mute != 0) {
        saa7134->mute_was_on = 1;
        dev->ctl_mute = 0;
        saa7134_tvaudio_setmute(dev);
    }

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

    err = snd_pcm_hw_constraint_step(runtime, 0,
                        SNDRV_PCM_HW_PARAM_PERIODS, 2);
    if (err < 0)
        return err;

    return 0;
}

/*
 * page callback (needed for mmap)
 */

static struct page *snd_card_saa7134_page(struct snd_pcm_substream *substream,
                    unsigned long offset)
{
    void *pageptr = substream->runtime->dma_area + offset;
    return vmalloc_to_page(pageptr);
}

/*
 * ALSA capture callbacks definition
 */

static struct snd_pcm_ops snd_card_saa7134_capture_ops = {
    .open =         snd_card_saa7134_capture_open,
    .close =        snd_card_saa7134_capture_close,
    .ioctl =        snd_pcm_lib_ioctl,
    .hw_params =        snd_card_saa7134_hw_params,
    .hw_free =      snd_card_saa7134_hw_free,
    .prepare =      snd_card_saa7134_capture_prepare,
    .trigger =      snd_card_saa7134_capture_trigger,
    .pointer =      snd_card_saa7134_capture_pointer,
    .page =         snd_card_saa7134_page,
};

/*
 * ALSA PCM setup
 *
 *   Called when initializing the board. Sets up the name and hooks up
 *  the callbacks
 *
 */

static int snd_card_saa7134_pcm(snd_card_saa7134_t *saa7134, int device)
{
    struct snd_pcm *pcm;
    int err;

    if ((err = snd_pcm_new(saa7134->card, "SAA7134 PCM", device, 0, 1, &pcm)) < 0)
        return err;
    snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_card_saa7134_capture_ops);
    pcm->private_data = saa7134;
    pcm->info_flags = 0;
    strcpy(pcm->name, "SAA7134 PCM");
    return 0;
}

#define SAA713x_VOLUME(xname, xindex, addr) \
{ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, .index = xindex, \
  .info = snd_saa7134_volume_info, \
  .get = snd_saa7134_volume_get, .put = snd_saa7134_volume_put, \
  .private_value = addr }

static int snd_saa7134_volume_info(struct snd_kcontrol * kcontrol,
                   struct snd_ctl_elem_info * uinfo)
{
    uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
    uinfo->count = 2;
    uinfo->value.integer.min = 0;
    uinfo->value.integer.max = 20;
    return 0;
}

static int snd_saa7134_volume_get(struct snd_kcontrol * kcontrol,
                  struct snd_ctl_elem_value * ucontrol)
{
    snd_card_saa7134_t *chip = snd_kcontrol_chip(kcontrol);
    int addr = kcontrol->private_value;

    ucontrol->value.integer.value[0] = chip->mixer_volume[addr][0];
    ucontrol->value.integer.value[1] = chip->mixer_volume[addr][1];
    return 0;
}

static int snd_saa7134_volume_put(struct snd_kcontrol * kcontrol,
                  struct snd_ctl_elem_value * ucontrol)
{
    snd_card_saa7134_t *chip = snd_kcontrol_chip(kcontrol);
    struct saa7134_dev *dev = chip->dev;

    int change, addr = kcontrol->private_value;
    int left, right;

    left = ucontrol->value.integer.value[0];
    if (left < 0)
        left = 0;
    if (left > 20)
        left = 20;
    right = ucontrol->value.integer.value[1];
    if (right < 0)
        right = 0;
    if (right > 20)
        right = 20;
    spin_lock_irq(&chip->mixer_lock);
    change = 0;
    if (chip->mixer_volume[addr][0] != left) {
        change = 1;
        right = left;
    }
    if (chip->mixer_volume[addr][1] != right) {
        change = 1;
        left = right;
    }
    if (change) {
        switch (dev->pci->device) {
            case PCI_DEVICE_ID_PHILIPS_SAA7134:
                switch (addr) {
                    case MIXER_ADDR_TVTUNER:
                        left = 20;
                        break;
                    case MIXER_ADDR_LINE1:
                        saa_andorb(SAA7134_ANALOG_IO_SELECT,  0x10,
                               (left > 10) ? 0x00 : 0x10);
                        break;
                    case MIXER_ADDR_LINE2:
                        saa_andorb(SAA7134_ANALOG_IO_SELECT,  0x20,
                               (left > 10) ? 0x00 : 0x20);
                        break;
                }
                break;
            case PCI_DEVICE_ID_PHILIPS_SAA7133:
            case PCI_DEVICE_ID_PHILIPS_SAA7135:
                switch (addr) {
                    case MIXER_ADDR_TVTUNER:
                        left = 20;
                        break;
                    case MIXER_ADDR_LINE1:
                        saa_andorb(0x0594,  0x10,
                               (left > 10) ? 0x00 : 0x10);
                        break;
                    case MIXER_ADDR_LINE2:
                        saa_andorb(0x0594,  0x20,
                               (left > 10) ? 0x00 : 0x20);
                        break;
                }
                break;
        }
        chip->mixer_volume[addr][0] = left;
        chip->mixer_volume[addr][1] = right;
    }
    spin_unlock_irq(&chip->mixer_lock);
    return change;
}

#define SAA713x_CAPSRC(xname, xindex, addr) \
{ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, .index = xindex, \
  .info = snd_saa7134_capsrc_info, \
  .get = snd_saa7134_capsrc_get, .put = snd_saa7134_capsrc_put, \
  .private_value = addr }

static int snd_saa7134_capsrc_info(struct snd_kcontrol * kcontrol,
                   struct snd_ctl_elem_info * uinfo)
{
    uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
    uinfo->count = 2;
    uinfo->value.integer.min = 0;
    uinfo->value.integer.max = 1;
    return 0;
}

static int snd_saa7134_capsrc_get(struct snd_kcontrol * kcontrol,
                  struct snd_ctl_elem_value * ucontrol)
{
    snd_card_saa7134_t *chip = snd_kcontrol_chip(kcontrol);
    int addr = kcontrol->private_value;

    spin_lock_irq(&chip->mixer_lock);
    if (chip->capture_source_addr == addr) {
        ucontrol->value.integer.value[0] = chip->capture_source[0];
        ucontrol->value.integer.value[1] = chip->capture_source[1];
    } else {
        ucontrol->value.integer.value[0] = 0;
        ucontrol->value.integer.value[1] = 0;
    }
    spin_unlock_irq(&chip->mixer_lock);

    return 0;
}

static int snd_saa7134_capsrc_put(struct snd_kcontrol * kcontrol,
                  struct snd_ctl_elem_value * ucontrol)
{
    int left, right;
    left = ucontrol->value.integer.value[0] & 1;
    right = ucontrol->value.integer.value[1] & 1;

    return snd_saa7134_capsrc_set(kcontrol, left, right, false);
}

static struct snd_kcontrol_new snd_saa7134_volume_controls[] = {
SAA713x_VOLUME("Video Volume", 0, MIXER_ADDR_TVTUNER),
SAA713x_VOLUME("Line Volume", 1, MIXER_ADDR_LINE1),
SAA713x_VOLUME("Line Volume", 2, MIXER_ADDR_LINE2),
};

static struct snd_kcontrol_new snd_saa7134_capture_controls[] = {
SAA713x_CAPSRC("Video Capture Switch", 0, MIXER_ADDR_TVTUNER),
SAA713x_CAPSRC("Line Capture Switch", 1, MIXER_ADDR_LINE1),
SAA713x_CAPSRC("Line Capture Switch", 2, MIXER_ADDR_LINE2),
};

/*
 * ALSA mixer setup
 *
 *   Called when initializing the board. Sets up the name and hooks up
 *  the callbacks
 *
 */

static int snd_card_saa7134_new_mixer(snd_card_saa7134_t * chip)
{
    struct snd_card *card = chip->card;
    struct snd_kcontrol *kcontrol;
    unsigned int idx;
    int err, addr;

    strcpy(card->mixername, "SAA7134 Mixer");

    for (idx = 0; idx < ARRAY_SIZE(snd_saa7134_volume_controls); idx++) {
        kcontrol = snd_ctl_new1(&snd_saa7134_volume_controls[idx],
                    chip);
        err = snd_ctl_add(card, kcontrol);
        if (err < 0)
            return err;
    }

    for (idx = 0; idx < ARRAY_SIZE(snd_saa7134_capture_controls); idx++) {
        kcontrol = snd_ctl_new1(&snd_saa7134_capture_controls[idx],
                    chip);
        addr = snd_saa7134_capture_controls[idx].private_value;
        chip->capture_ctl[addr] = kcontrol;
        err = snd_ctl_add(card, kcontrol);
        if (err < 0)
            return err;
    }

    chip->capture_source_addr = MIXER_ADDR_UNSELECTED;
    return 0;
}

static void snd_saa7134_free(struct snd_card * card)
{
    snd_card_saa7134_t *chip = card->private_data;

    if (chip->dev->dmasound.priv_data == NULL)
        return;

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

    chip->dev->dmasound.priv_data = NULL;

}

/*
 * ALSA initialization
 *
 *   Called by the init routine, once for each saa7134 device present,
 *  it creates the basic structures and registers the ALSA devices
 *
 */

static int alsa_card_saa7134_create(struct saa7134_dev *dev, int devnum)
{

    struct snd_card *card;
    snd_card_saa7134_t *chip;
    int err;


    if (devnum >= SNDRV_CARDS)
        return -ENODEV;
    if (!enable[devnum])
        return -ENODEV;

    err = snd_card_create(index[devnum], id[devnum], THIS_MODULE,
                  sizeof(snd_card_saa7134_t), &card);
    if (err < 0)
        return err;

    strcpy(card->driver, "SAA7134");

    /* Card "creation" */

    card->private_free = snd_saa7134_free;
    chip = card->private_data;

    spin_lock_init(&chip->lock);
    spin_lock_init(&chip->mixer_lock);

    chip->dev = dev;

    chip->card = card;

    chip->pci = dev->pci;
    chip->iobase = pci_resource_start(dev->pci, 0);


    err = request_irq(dev->pci->irq, saa7134_alsa_irq,
                IRQF_SHARED | IRQF_DISABLED, dev->name,
                (void*) &dev->dmasound);

    if (err < 0) {
        printk(KERN_ERR "%s: can't get IRQ %d for ALSA\n",
            dev->name, dev->pci->irq);
        goto __nodev;
    }

    chip->irq = dev->pci->irq;

    mutex_init(&dev->dmasound.lock);

    if ((err = snd_card_saa7134_new_mixer(chip)) < 0)
        goto __nodev;

    if ((err = snd_card_saa7134_pcm(chip, 0)) < 0)
        goto __nodev;

    snd_card_set_dev(card, &chip->pci->dev);

    /* End of "creation" */

    strcpy(card->shortname, "SAA7134");
    sprintf(card->longname, "%s at 0x%lx irq %d",
        chip->dev->name, chip->iobase, chip->irq);

    printk(KERN_INFO "%s/alsa: %s registered as card %d\n",dev->name,card->longname,index[devnum]);

    if ((err = snd_card_register(card)) == 0) {
        snd_saa7134_cards[devnum] = card;
        return 0;
    }

__nodev:
    snd_card_free(card);
    return err;
}


static int alsa_device_init(struct saa7134_dev *dev)
{
    dev->dmasound.priv_data = dev;
    alsa_card_saa7134_create(dev,dev->nr);
    return 1;
}

static int alsa_device_exit(struct saa7134_dev *dev)
{

    snd_card_free(snd_saa7134_cards[dev->nr]);
    snd_saa7134_cards[dev->nr] = NULL;
    return 1;
}

/*
 * Module initializer
 *
 * Loops through present saa7134 cards, and assigns an ALSA device
 * to each one
 *
 */

static int saa7134_alsa_init(void)
{
    struct saa7134_dev *dev = NULL;
    struct list_head *list;

    saa7134_dmasound_init = alsa_device_init;
    saa7134_dmasound_exit = alsa_device_exit;

    printk(KERN_INFO "saa7134 ALSA driver for DMA sound loaded\n");

    list_for_each(list,&saa7134_devlist) {
        dev = list_entry(list, struct saa7134_dev, devlist);
        if (dev->pci->device == PCI_DEVICE_ID_PHILIPS_SAA7130)
            printk(KERN_INFO "%s/alsa: %s doesn't support digital audio\n",
                dev->name, saa7134_boards[dev->board].name);
        else
            alsa_device_init(dev);
    }

    if (dev == NULL)
        printk(KERN_INFO "saa7134 ALSA: no saa7134 cards found\n");

    return 0;

}

/*
 * Module destructor
 */

static void saa7134_alsa_exit(void)
{
    int idx;

    for (idx = 0; idx < SNDRV_CARDS; idx++) {
        snd_card_free(snd_saa7134_cards[idx]);
    }

    saa7134_dmasound_init = NULL;
    saa7134_dmasound_exit = NULL;
    printk(KERN_INFO "saa7134 ALSA driver for DMA sound unloaded\n");

    return;
}

/* We initialize this late, to make sure the sound system is up and running */
late_initcall(saa7134_alsa_init);
module_exit(saa7134_alsa_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Ricardo Cerqueira");