at73c213.c

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/*
 * Driver for AT73C213 16-bit stereo DAC connected to Atmel SSC
 *
 * Copyright (C) 2006-2007 Atmel Norway
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 */

/*#define DEBUG*/

#include <linux/clk.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <linux/io.h>

#include <sound/initval.h>
#include <sound/control.h>
#include <sound/core.h>
#include <sound/pcm.h>

#include <linux/atmel-ssc.h>

#include <linux/spi/spi.h>
#include <linux/spi/at73c213.h>

#include "at73c213.h"

#define BITRATE_MIN  8000 /* Hardware limit? */
#define BITRATE_TARGET  CONFIG_SND_AT73C213_TARGET_BITRATE
#define BITRATE_MAX 50000 /* Hardware limit. */

/* Initial (hardware reset) AT73C213 register values. */
static u8 snd_at73c213_original_image[18] =
{
    0x00,   /* 00 - CTRL    */
    0x05,   /* 01 - LLIG    */
    0x05,   /* 02 - RLIG    */
    0x08,   /* 03 - LPMG    */
    0x08,   /* 04 - RPMG    */
    0x00,   /* 05 - LLOG    */
    0x00,   /* 06 - RLOG    */
    0x22,   /* 07 - OLC     */
    0x09,   /* 08 - MC      */
    0x00,   /* 09 - CSFC    */
    0x00,   /* 0A - MISC    */
    0x00,   /* 0B -         */
    0x00,   /* 0C - PRECH   */
    0x05,   /* 0D - AUXG    */
    0x00,   /* 0E -         */
    0x00,   /* 0F -         */
    0x00,   /* 10 - RST     */
    0x00,   /* 11 - PA_CTRL */
};

struct snd_at73c213 {
    struct snd_card         *card;
    struct snd_pcm          *pcm;
    struct snd_pcm_substream    *substream;
    struct at73c213_board_info  *board;
    int             irq;
    int             period;
    unsigned long           bitrate;
    struct ssc_device       *ssc;
    struct spi_device       *spi;
    u8              spi_wbuffer[2];
    u8              spi_rbuffer[2];
    /* Image of the SPI registers in AT73C213. */
    u8              reg_image[18];
    /* Protect SSC registers against concurrent access. */
    spinlock_t          lock;
    /* Protect mixer registers against concurrent access. */
    struct mutex            mixer_lock;
};

#define get_chip(card) ((struct snd_at73c213 *)card->private_data)

static int
snd_at73c213_write_reg(struct snd_at73c213 *chip, u8 reg, u8 val)
{
    struct spi_message msg;
    struct spi_transfer msg_xfer = {
        .len        = 2,
        .cs_change  = 0,
    };
    int retval;

    spi_message_init(&msg);

    chip->spi_wbuffer[0] = reg;
    chip->spi_wbuffer[1] = val;

    msg_xfer.tx_buf = chip->spi_wbuffer;
    msg_xfer.rx_buf = chip->spi_rbuffer;
    spi_message_add_tail(&msg_xfer, &msg);

    retval = spi_sync(chip->spi, &msg);

    if (!retval)
        chip->reg_image[reg] = val;

    return retval;
}

static struct snd_pcm_hardware snd_at73c213_playback_hw = {
    .info       = SNDRV_PCM_INFO_INTERLEAVED |
              SNDRV_PCM_INFO_BLOCK_TRANSFER,
    .formats    = SNDRV_PCM_FMTBIT_S16_BE,
    .rates      = SNDRV_PCM_RATE_CONTINUOUS,
    .rate_min   = 8000,  /* Replaced by chip->bitrate later. */
    .rate_max   = 50000, /* Replaced by chip->bitrate later. */
    .channels_min   = 1,
    .channels_max   = 2,
    .buffer_bytes_max = 64 * 1024 - 1,
    .period_bytes_min = 512,
    .period_bytes_max = 64 * 1024 - 1,
    .periods_min    = 4,
    .periods_max    = 1024,
};

/*
 * Calculate and set bitrate and divisions.
 */
static int snd_at73c213_set_bitrate(struct snd_at73c213 *chip)
{
    unsigned long ssc_rate = clk_get_rate(chip->ssc->clk);
    unsigned long dac_rate_new, ssc_div;
    int status;
    unsigned long ssc_div_max, ssc_div_min;
    int max_tries;

    /*
     * We connect two clocks here, picking divisors so the I2S clocks
     * out data at the same rate the DAC clocks it in ... and as close
     * as practical to the desired target rate.
     *
     * The DAC master clock (MCLK) is programmable, and is either 256
     * or (not here) 384 times the I2S output clock (BCLK).
     */

    /* SSC clock / (bitrate * stereo * 16-bit). */
    ssc_div = ssc_rate / (BITRATE_TARGET * 2 * 16);
    ssc_div_min = ssc_rate / (BITRATE_MAX * 2 * 16);
    ssc_div_max = ssc_rate / (BITRATE_MIN * 2 * 16);
    max_tries = (ssc_div_max - ssc_div_min) / 2;

    if (max_tries < 1)
        max_tries = 1;

    /* ssc_div must be even. */
    ssc_div = (ssc_div + 1) & ~1UL;

    if ((ssc_rate / (ssc_div * 2 * 16)) < BITRATE_MIN) {
        ssc_div -= 2;
        if ((ssc_rate / (ssc_div * 2 * 16)) > BITRATE_MAX)
            return -ENXIO;
    }

    /* Search for a possible bitrate. */
    do {
        /* SSC clock / (ssc divider * 16-bit * stereo). */
        if ((ssc_rate / (ssc_div * 2 * 16)) < BITRATE_MIN)
            return -ENXIO;

        /* 256 / (2 * 16) = 8 */
        dac_rate_new = 8 * (ssc_rate / ssc_div);

        status = clk_round_rate(chip->board->dac_clk, dac_rate_new);
        if (status < 0)
            return status;

        /* Ignore difference smaller than 256 Hz. */
        if ((status/256) == (dac_rate_new/256))
            goto set_rate;

        ssc_div += 2;
    } while (--max_tries);

    /* Not able to find a valid bitrate. */
    return -ENXIO;

set_rate:
    status = clk_set_rate(chip->board->dac_clk, status);
    if (status < 0)
        return status;

    /* Set divider in SSC device. */
    ssc_writel(chip->ssc->regs, CMR, ssc_div/2);

    /* SSC clock / (ssc divider * 16-bit * stereo). */
    chip->bitrate = ssc_rate / (ssc_div * 16 * 2);

    dev_info(&chip->spi->dev,
            "at73c213: supported bitrate is %lu (%lu divider)\n",
            chip->bitrate, ssc_div);

    return 0;
}

static int snd_at73c213_pcm_open(struct snd_pcm_substream *substream)
{
    struct snd_at73c213 *chip = snd_pcm_substream_chip(substream);
    struct snd_pcm_runtime *runtime = substream->runtime;
    int err;

    /* ensure buffer_size is a multiple of period_size */
    err = snd_pcm_hw_constraint_integer(runtime,
                    SNDRV_PCM_HW_PARAM_PERIODS);
    if (err < 0)
        return err;
    snd_at73c213_playback_hw.rate_min = chip->bitrate;
    snd_at73c213_playback_hw.rate_max = chip->bitrate;
    runtime->hw = snd_at73c213_playback_hw;
    chip->substream = substream;

    return 0;
}

static int snd_at73c213_pcm_close(struct snd_pcm_substream *substream)
{
    struct snd_at73c213 *chip = snd_pcm_substream_chip(substream);
    chip->substream = NULL;
    return 0;
}

static int snd_at73c213_pcm_hw_params(struct snd_pcm_substream *substream,
                 struct snd_pcm_hw_params *hw_params)
{
    struct snd_at73c213 *chip = snd_pcm_substream_chip(substream);
    int channels = params_channels(hw_params);
    int val;

    val = ssc_readl(chip->ssc->regs, TFMR);
    val = SSC_BFINS(TFMR_DATNB, channels - 1, val);
    ssc_writel(chip->ssc->regs, TFMR, val);

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

static int snd_at73c213_pcm_hw_free(struct snd_pcm_substream *substream)
{
    return snd_pcm_lib_free_pages(substream);
}

static int snd_at73c213_pcm_prepare(struct snd_pcm_substream *substream)
{
    struct snd_at73c213 *chip = snd_pcm_substream_chip(substream);
    struct snd_pcm_runtime *runtime = substream->runtime;
    int block_size;

    block_size = frames_to_bytes(runtime, runtime->period_size);

    chip->period = 0;

    ssc_writel(chip->ssc->regs, PDC_TPR,
            (long)runtime->dma_addr);
    ssc_writel(chip->ssc->regs, PDC_TCR,
            runtime->period_size * runtime->channels);
    ssc_writel(chip->ssc->regs, PDC_TNPR,
            (long)runtime->dma_addr + block_size);
    ssc_writel(chip->ssc->regs, PDC_TNCR,
            runtime->period_size * runtime->channels);

    return 0;
}

static int snd_at73c213_pcm_trigger(struct snd_pcm_substream *substream,
                   int cmd)
{
    struct snd_at73c213 *chip = snd_pcm_substream_chip(substream);
    int retval = 0;

    spin_lock(&chip->lock);

    switch (cmd) {
    case SNDRV_PCM_TRIGGER_START:
        ssc_writel(chip->ssc->regs, IER, SSC_BIT(IER_ENDTX));
        ssc_writel(chip->ssc->regs, PDC_PTCR, SSC_BIT(PDC_PTCR_TXTEN));
        break;
    case SNDRV_PCM_TRIGGER_STOP:
        ssc_writel(chip->ssc->regs, PDC_PTCR, SSC_BIT(PDC_PTCR_TXTDIS));
        ssc_writel(chip->ssc->regs, IDR, SSC_BIT(IDR_ENDTX));
        break;
    default:
        dev_dbg(&chip->spi->dev, "spurious command %x\n", cmd);
        retval = -EINVAL;
        break;
    }

    spin_unlock(&chip->lock);

    return retval;
}

static snd_pcm_uframes_t
snd_at73c213_pcm_pointer(struct snd_pcm_substream *substream)
{
    struct snd_at73c213 *chip = snd_pcm_substream_chip(substream);
    struct snd_pcm_runtime *runtime = substream->runtime;
    snd_pcm_uframes_t pos;
    unsigned long bytes;

    bytes = ssc_readl(chip->ssc->regs, PDC_TPR)
        - (unsigned long)runtime->dma_addr;

    pos = bytes_to_frames(runtime, bytes);
    if (pos >= runtime->buffer_size)
        pos -= runtime->buffer_size;

    return pos;
}

static struct snd_pcm_ops at73c213_playback_ops = {
    .open       = snd_at73c213_pcm_open,
    .close      = snd_at73c213_pcm_close,
    .ioctl      = snd_pcm_lib_ioctl,
    .hw_params  = snd_at73c213_pcm_hw_params,
    .hw_free    = snd_at73c213_pcm_hw_free,
    .prepare    = snd_at73c213_pcm_prepare,
    .trigger    = snd_at73c213_pcm_trigger,
    .pointer    = snd_at73c213_pcm_pointer,
};

static int __devinit snd_at73c213_pcm_new(struct snd_at73c213 *chip, int device)
{
    struct snd_pcm *pcm;
    int retval;

    retval = snd_pcm_new(chip->card, chip->card->shortname,
            device, 1, 0, &pcm);
    if (retval < 0)
        goto out;

    pcm->private_data = chip;
    pcm->info_flags = SNDRV_PCM_INFO_BLOCK_TRANSFER;
    strcpy(pcm->name, "at73c213");
    chip->pcm = pcm;

    snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &at73c213_playback_ops);

    retval = snd_pcm_lib_preallocate_pages_for_all(chip->pcm,
            SNDRV_DMA_TYPE_DEV, &chip->ssc->pdev->dev,
            64 * 1024, 64 * 1024);
out:
    return retval;
}

static irqreturn_t snd_at73c213_interrupt(int irq, void *dev_id)
{
    struct snd_at73c213 *chip = dev_id;
    struct snd_pcm_runtime *runtime = chip->substream->runtime;
    u32 status;
    int offset;
    int block_size;
    int next_period;
    int retval = IRQ_NONE;

    spin_lock(&chip->lock);

    block_size = frames_to_bytes(runtime, runtime->period_size);
    status = ssc_readl(chip->ssc->regs, IMR);

    if (status & SSC_BIT(IMR_ENDTX)) {
        chip->period++;
        if (chip->period == runtime->periods)
            chip->period = 0;
        next_period = chip->period + 1;
        if (next_period == runtime->periods)
            next_period = 0;

        offset = block_size * next_period;

        ssc_writel(chip->ssc->regs, PDC_TNPR,
                (long)runtime->dma_addr + offset);
        ssc_writel(chip->ssc->regs, PDC_TNCR,
                runtime->period_size * runtime->channels);
        retval = IRQ_HANDLED;
    }

    ssc_readl(chip->ssc->regs, IMR);
    spin_unlock(&chip->lock);

    if (status & SSC_BIT(IMR_ENDTX))
        snd_pcm_period_elapsed(chip->substream);

    return retval;
}

/*
 * Mixer functions.
 */
static int snd_at73c213_mono_get(struct snd_kcontrol *kcontrol,
                 struct snd_ctl_elem_value *ucontrol)
{
    struct snd_at73c213 *chip = snd_kcontrol_chip(kcontrol);
    int reg = kcontrol->private_value & 0xff;
    int shift = (kcontrol->private_value >> 8) & 0xff;
    int mask = (kcontrol->private_value >> 16) & 0xff;
    int invert = (kcontrol->private_value >> 24) & 0xff;

    mutex_lock(&chip->mixer_lock);

    ucontrol->value.integer.value[0] =
        (chip->reg_image[reg] >> shift) & mask;

    if (invert)
        ucontrol->value.integer.value[0] =
            mask - ucontrol->value.integer.value[0];

    mutex_unlock(&chip->mixer_lock);

    return 0;
}

static int snd_at73c213_mono_put(struct snd_kcontrol *kcontrol,
                 struct snd_ctl_elem_value *ucontrol)
{
    struct snd_at73c213 *chip = snd_kcontrol_chip(kcontrol);
    int reg = kcontrol->private_value & 0xff;
    int shift = (kcontrol->private_value >> 8) & 0xff;
    int mask = (kcontrol->private_value >> 16) & 0xff;
    int invert = (kcontrol->private_value >> 24) & 0xff;
    int change, retval;
    unsigned short val;

    val = (ucontrol->value.integer.value[0] & mask);
    if (invert)
        val = mask - val;
    val <<= shift;

    mutex_lock(&chip->mixer_lock);

    val = (chip->reg_image[reg] & ~(mask << shift)) | val;
    change = val != chip->reg_image[reg];
    retval = snd_at73c213_write_reg(chip, reg, val);

    mutex_unlock(&chip->mixer_lock);

    if (retval)
        return retval;

    return change;
}

static int snd_at73c213_stereo_info(struct snd_kcontrol *kcontrol,
                  struct snd_ctl_elem_info *uinfo)
{
    int mask = (kcontrol->private_value >> 24) & 0xff;

    if (mask == 1)
        uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
    else
        uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;

    uinfo->count = 2;
    uinfo->value.integer.min = 0;
    uinfo->value.integer.max = mask;

    return 0;
}

static int snd_at73c213_stereo_get(struct snd_kcontrol *kcontrol,
                 struct snd_ctl_elem_value *ucontrol)
{
    struct snd_at73c213 *chip = snd_kcontrol_chip(kcontrol);
    int left_reg = kcontrol->private_value & 0xff;
    int right_reg = (kcontrol->private_value >> 8) & 0xff;
    int shift_left = (kcontrol->private_value >> 16) & 0x07;
    int shift_right = (kcontrol->private_value >> 19) & 0x07;
    int mask = (kcontrol->private_value >> 24) & 0xff;
    int invert = (kcontrol->private_value >> 22) & 1;

    mutex_lock(&chip->mixer_lock);

    ucontrol->value.integer.value[0] =
        (chip->reg_image[left_reg] >> shift_left) & mask;
    ucontrol->value.integer.value[1] =
        (chip->reg_image[right_reg] >> shift_right) & mask;

    if (invert) {
        ucontrol->value.integer.value[0] =
            mask - ucontrol->value.integer.value[0];
        ucontrol->value.integer.value[1] =
            mask - ucontrol->value.integer.value[1];
    }

    mutex_unlock(&chip->mixer_lock);

    return 0;
}

static int snd_at73c213_stereo_put(struct snd_kcontrol *kcontrol,
                 struct snd_ctl_elem_value *ucontrol)
{
    struct snd_at73c213 *chip = snd_kcontrol_chip(kcontrol);
    int left_reg = kcontrol->private_value & 0xff;
    int right_reg = (kcontrol->private_value >> 8) & 0xff;
    int shift_left = (kcontrol->private_value >> 16) & 0x07;
    int shift_right = (kcontrol->private_value >> 19) & 0x07;
    int mask = (kcontrol->private_value >> 24) & 0xff;
    int invert = (kcontrol->private_value >> 22) & 1;
    int change, retval;
    unsigned short val1, val2;

    val1 = ucontrol->value.integer.value[0] & mask;
    val2 = ucontrol->value.integer.value[1] & mask;
    if (invert) {
        val1 = mask - val1;
        val2 = mask - val2;
    }
    val1 <<= shift_left;
    val2 <<= shift_right;

    mutex_lock(&chip->mixer_lock);

    val1 = (chip->reg_image[left_reg] & ~(mask << shift_left)) | val1;
    val2 = (chip->reg_image[right_reg] & ~(mask << shift_right)) | val2;
    change = val1 != chip->reg_image[left_reg]
        || val2 != chip->reg_image[right_reg];
    retval = snd_at73c213_write_reg(chip, left_reg, val1);
    if (retval) {
        mutex_unlock(&chip->mixer_lock);
        goto out;
    }
    retval = snd_at73c213_write_reg(chip, right_reg, val2);
    if (retval) {
        mutex_unlock(&chip->mixer_lock);
        goto out;
    }

    mutex_unlock(&chip->mixer_lock);

    return change;

out:
    return retval;
}

#define snd_at73c213_mono_switch_info   snd_ctl_boolean_mono_info

static int snd_at73c213_mono_switch_get(struct snd_kcontrol *kcontrol,
                 struct snd_ctl_elem_value *ucontrol)
{
    struct snd_at73c213 *chip = snd_kcontrol_chip(kcontrol);
    int reg = kcontrol->private_value & 0xff;
    int shift = (kcontrol->private_value >> 8) & 0xff;
    int invert = (kcontrol->private_value >> 24) & 0xff;

    mutex_lock(&chip->mixer_lock);

    ucontrol->value.integer.value[0] =
        (chip->reg_image[reg] >> shift) & 0x01;

    if (invert)
        ucontrol->value.integer.value[0] =
            0x01 - ucontrol->value.integer.value[0];

    mutex_unlock(&chip->mixer_lock);

    return 0;
}

static int snd_at73c213_mono_switch_put(struct snd_kcontrol *kcontrol,
                 struct snd_ctl_elem_value *ucontrol)
{
    struct snd_at73c213 *chip = snd_kcontrol_chip(kcontrol);
    int reg = kcontrol->private_value & 0xff;
    int shift = (kcontrol->private_value >> 8) & 0xff;
    int mask = (kcontrol->private_value >> 16) & 0xff;
    int invert = (kcontrol->private_value >> 24) & 0xff;
    int change, retval;
    unsigned short val;

    if (ucontrol->value.integer.value[0])
        val = mask;
    else
        val = 0;

    if (invert)
        val = mask - val;
    val <<= shift;

    mutex_lock(&chip->mixer_lock);

    val |= (chip->reg_image[reg] & ~(mask << shift));
    change = val != chip->reg_image[reg];

    retval = snd_at73c213_write_reg(chip, reg, val);

    mutex_unlock(&chip->mixer_lock);

    if (retval)
        return retval;

    return change;
}

static int snd_at73c213_pa_volume_info(struct snd_kcontrol *kcontrol,
                  struct snd_ctl_elem_info *uinfo)
{
    uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
    uinfo->count = 1;
    uinfo->value.integer.min = 0;
    uinfo->value.integer.max = ((kcontrol->private_value >> 16) & 0xff) - 1;

    return 0;
}

static int snd_at73c213_line_capture_volume_info(
        struct snd_kcontrol *kcontrol,
        struct snd_ctl_elem_info *uinfo)
{
    uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
    uinfo->count = 2;
    /* When inverted will give values 0x10001 => 0. */
    uinfo->value.integer.min = 14;
    uinfo->value.integer.max = 31;

    return 0;
}

static int snd_at73c213_aux_capture_volume_info(
        struct snd_kcontrol *kcontrol,
        struct snd_ctl_elem_info *uinfo)
{
    uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
    uinfo->count = 1;
    /* When inverted will give values 0x10001 => 0. */
    uinfo->value.integer.min = 14;
    uinfo->value.integer.max = 31;

    return 0;
}

#define AT73C213_MONO_SWITCH(xname, xindex, reg, shift, mask, invert)   \
{                                   \
    .iface = SNDRV_CTL_ELEM_IFACE_MIXER,                \
    .name = xname,                          \
    .index = xindex,                        \
    .info = snd_at73c213_mono_switch_info,              \
    .get = snd_at73c213_mono_switch_get,                \
    .put = snd_at73c213_mono_switch_put,                \
    .private_value = (reg | (shift << 8) | (mask << 16) | (invert << 24)) \
}

#define AT73C213_STEREO(xname, xindex, left_reg, right_reg, shift_left, shift_right, mask, invert) \
{                                   \
    .iface = SNDRV_CTL_ELEM_IFACE_MIXER,                \
    .name = xname,                          \
    .index = xindex,                        \
    .info = snd_at73c213_stereo_info,               \
    .get = snd_at73c213_stereo_get,                 \
    .put = snd_at73c213_stereo_put,                 \
    .private_value = (left_reg | (right_reg << 8)           \
            | (shift_left << 16) | (shift_right << 19)  \
            | (mask << 24) | (invert << 22))        \
}

static struct snd_kcontrol_new snd_at73c213_controls[] __devinitdata = {
AT73C213_STEREO("Master Playback Volume", 0, DAC_LMPG, DAC_RMPG, 0, 0, 0x1f, 1),
AT73C213_STEREO("Master Playback Switch", 0, DAC_LMPG, DAC_RMPG, 5, 5, 1, 1),
AT73C213_STEREO("PCM Playback Volume", 0, DAC_LLOG, DAC_RLOG, 0, 0, 0x1f, 1),
AT73C213_STEREO("PCM Playback Switch", 0, DAC_LLOG, DAC_RLOG, 5, 5, 1, 1),
AT73C213_MONO_SWITCH("Mono PA Playback Switch", 0, DAC_CTRL, DAC_CTRL_ONPADRV,
             0x01, 0),
{
    .iface  = SNDRV_CTL_ELEM_IFACE_MIXER,
    .name   = "PA Playback Volume",
    .index  = 0,
    .info   = snd_at73c213_pa_volume_info,
    .get    = snd_at73c213_mono_get,
    .put    = snd_at73c213_mono_put,
    .private_value  = PA_CTRL | (PA_CTRL_APAGAIN << 8) | \
        (0x0f << 16) | (1 << 24),
},
AT73C213_MONO_SWITCH("PA High Gain Playback Switch", 0, PA_CTRL, PA_CTRL_APALP,
             0x01, 1),
AT73C213_MONO_SWITCH("PA Playback Switch", 0, PA_CTRL, PA_CTRL_APAON, 0x01, 0),
{
    .iface  = SNDRV_CTL_ELEM_IFACE_MIXER,
    .name   = "Aux Capture Volume",
    .index  = 0,
    .info   = snd_at73c213_aux_capture_volume_info,
    .get    = snd_at73c213_mono_get,
    .put    = snd_at73c213_mono_put,
    .private_value  = DAC_AUXG | (0 << 8) | (0x1f << 16) | (1 << 24),
},
AT73C213_MONO_SWITCH("Aux Capture Switch", 0, DAC_CTRL, DAC_CTRL_ONAUXIN,
             0x01, 0),
{
    .iface  = SNDRV_CTL_ELEM_IFACE_MIXER,
    .name   = "Line Capture Volume",
    .index  = 0,
    .info   = snd_at73c213_line_capture_volume_info,
    .get    = snd_at73c213_stereo_get,
    .put    = snd_at73c213_stereo_put,
    .private_value  = DAC_LLIG | (DAC_RLIG << 8) | (0 << 16) | (0 << 19)
        | (0x1f << 24) | (1 << 22),
},
AT73C213_MONO_SWITCH("Line Capture Switch", 0, DAC_CTRL, 0, 0x03, 0),
};

static int __devinit snd_at73c213_mixer(struct snd_at73c213 *chip)
{
    struct snd_card *card;
    int errval, idx;

    if (chip == NULL || chip->pcm == NULL)
        return -EINVAL;

    card = chip->card;

    strcpy(card->mixername, chip->pcm->name);

    for (idx = 0; idx < ARRAY_SIZE(snd_at73c213_controls); idx++) {
        errval = snd_ctl_add(card,
                snd_ctl_new1(&snd_at73c213_controls[idx],
                    chip));
        if (errval < 0)
            goto cleanup;
    }

    return 0;

cleanup:
    for (idx = 1; idx < ARRAY_SIZE(snd_at73c213_controls) + 1; idx++) {
        struct snd_kcontrol *kctl;
        kctl = snd_ctl_find_numid(card, idx);
        if (kctl)
            snd_ctl_remove(card, kctl);
    }
    return errval;
}

/*
 * Device functions
 */
static int __devinit snd_at73c213_ssc_init(struct snd_at73c213 *chip)
{
    /*
     * Continuous clock output.
     * Starts on falling TF.
     * Delay 1 cycle (1 bit).
     * Periode is 16 bit (16 - 1).
     */
    ssc_writel(chip->ssc->regs, TCMR,
            SSC_BF(TCMR_CKO, 1)
            | SSC_BF(TCMR_START, 4)
            | SSC_BF(TCMR_STTDLY, 1)
            | SSC_BF(TCMR_PERIOD, 16 - 1));
    /*
     * Data length is 16 bit (16 - 1).
     * Transmit MSB first.
     * Transmit 2 words each transfer.
     * Frame sync length is 16 bit (16 - 1).
     * Frame starts on negative pulse.
     */
    ssc_writel(chip->ssc->regs, TFMR,
            SSC_BF(TFMR_DATLEN, 16 - 1)
            | SSC_BIT(TFMR_MSBF)
            | SSC_BF(TFMR_DATNB, 1)
            | SSC_BF(TFMR_FSLEN, 16 - 1)
            | SSC_BF(TFMR_FSOS, 1));

    return 0;
}

static int __devinit snd_at73c213_chip_init(struct snd_at73c213 *chip)
{
    int retval;
    unsigned char dac_ctrl = 0;

    retval = snd_at73c213_set_bitrate(chip);
    if (retval)
        goto out;

    /* Enable DAC master clock. */
    clk_enable(chip->board->dac_clk);

    /* Initialize at73c213 on SPI bus. */
    retval = snd_at73c213_write_reg(chip, DAC_RST, 0x04);
    if (retval)
        goto out_clk;
    msleep(1);
    retval = snd_at73c213_write_reg(chip, DAC_RST, 0x03);
    if (retval)
        goto out_clk;

    /* Precharge everything. */
    retval = snd_at73c213_write_reg(chip, DAC_PRECH, 0xff);
    if (retval)
        goto out_clk;
    retval = snd_at73c213_write_reg(chip, PA_CTRL, (1<<PA_CTRL_APAPRECH));
    if (retval)
        goto out_clk;
    retval = snd_at73c213_write_reg(chip, DAC_CTRL,
            (1<<DAC_CTRL_ONLNOL) | (1<<DAC_CTRL_ONLNOR));
    if (retval)
        goto out_clk;

    msleep(50);

    /* Stop precharging PA. */
    retval = snd_at73c213_write_reg(chip, PA_CTRL,
            (1<<PA_CTRL_APALP) | 0x0f);
    if (retval)
        goto out_clk;

    msleep(450);

    /* Stop precharging DAC, turn on master power. */
    retval = snd_at73c213_write_reg(chip, DAC_PRECH, (1<<DAC_PRECH_ONMSTR));
    if (retval)
        goto out_clk;

    msleep(1);

    /* Turn on DAC. */
    dac_ctrl = (1<<DAC_CTRL_ONDACL) | (1<<DAC_CTRL_ONDACR)
        | (1<<DAC_CTRL_ONLNOL) | (1<<DAC_CTRL_ONLNOR);

    retval = snd_at73c213_write_reg(chip, DAC_CTRL, dac_ctrl);
    if (retval)
        goto out_clk;

    /* Mute sound. */
    retval = snd_at73c213_write_reg(chip, DAC_LMPG, 0x3f);
    if (retval)
        goto out_clk;
    retval = snd_at73c213_write_reg(chip, DAC_RMPG, 0x3f);
    if (retval)
        goto out_clk;
    retval = snd_at73c213_write_reg(chip, DAC_LLOG, 0x3f);
    if (retval)
        goto out_clk;
    retval = snd_at73c213_write_reg(chip, DAC_RLOG, 0x3f);
    if (retval)
        goto out_clk;
    retval = snd_at73c213_write_reg(chip, DAC_LLIG, 0x11);
    if (retval)
        goto out_clk;
    retval = snd_at73c213_write_reg(chip, DAC_RLIG, 0x11);
    if (retval)
        goto out_clk;
    retval = snd_at73c213_write_reg(chip, DAC_AUXG, 0x11);
    if (retval)
        goto out_clk;

    /* Enable I2S device, i.e. clock output. */
    ssc_writel(chip->ssc->regs, CR, SSC_BIT(CR_TXEN));

    goto out;

out_clk:
    clk_disable(chip->board->dac_clk);
out:
    return retval;
}

static int snd_at73c213_dev_free(struct snd_device *device)
{
    struct snd_at73c213 *chip = device->device_data;

    ssc_writel(chip->ssc->regs, CR, SSC_BIT(CR_TXDIS));
    if (chip->irq >= 0) {
        free_irq(chip->irq, chip);
        chip->irq = -1;
    }

    return 0;
}

static int __devinit snd_at73c213_dev_init(struct snd_card *card,
                     struct spi_device *spi)
{
    static struct snd_device_ops ops = {
        .dev_free   = snd_at73c213_dev_free,
    };
    struct snd_at73c213 *chip = get_chip(card);
    int irq, retval;

    irq = chip->ssc->irq;
    if (irq < 0)
        return irq;

    spin_lock_init(&chip->lock);
    mutex_init(&chip->mixer_lock);
    chip->card = card;
    chip->irq = -1;

    retval = request_irq(irq, snd_at73c213_interrupt, 0, "at73c213", chip);
    if (retval) {
        dev_dbg(&chip->spi->dev, "unable to request irq %d\n", irq);
        goto out;
    }
    chip->irq = irq;

    memcpy(&chip->reg_image, &snd_at73c213_original_image,
            sizeof(snd_at73c213_original_image));

    retval = snd_at73c213_ssc_init(chip);
    if (retval)
        goto out_irq;

    retval = snd_at73c213_chip_init(chip);
    if (retval)
        goto out_irq;

    retval = snd_at73c213_pcm_new(chip, 0);
    if (retval)
        goto out_irq;

    retval = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops);
    if (retval)
        goto out_irq;

    retval = snd_at73c213_mixer(chip);
    if (retval)
        goto out_snd_dev;

    snd_card_set_dev(card, &spi->dev);

    goto out;

out_snd_dev:
    snd_device_free(card, chip);
out_irq:
    free_irq(chip->irq, chip);
    chip->irq = -1;
out:
    return retval;
}

static int __devinit snd_at73c213_probe(struct spi_device *spi)
{
    struct snd_card         *card;
    struct snd_at73c213     *chip;
    struct at73c213_board_info  *board;
    int             retval;
    char                id[16];

    board = spi->dev.platform_data;
    if (!board) {
        dev_dbg(&spi->dev, "no platform_data\n");
        return -ENXIO;
    }

    if (!board->dac_clk) {
        dev_dbg(&spi->dev, "no DAC clk\n");
        return -ENXIO;
    }

    if (IS_ERR(board->dac_clk)) {
        dev_dbg(&spi->dev, "no DAC clk\n");
        return PTR_ERR(board->dac_clk);
    }

    /* Allocate "card" using some unused identifiers. */
    snprintf(id, sizeof id, "at73c213_%d", board->ssc_id);
    retval = snd_card_create(-1, id, THIS_MODULE,
                 sizeof(struct snd_at73c213), &card);
    if (retval < 0)
        goto out;

    chip = card->private_data;
    chip->spi = spi;
    chip->board = board;

    chip->ssc = ssc_request(board->ssc_id);
    if (IS_ERR(chip->ssc)) {
        dev_dbg(&spi->dev, "could not get ssc%d device\n",
                board->ssc_id);
        retval = PTR_ERR(chip->ssc);
        goto out_card;
    }

    retval = snd_at73c213_dev_init(card, spi);
    if (retval)
        goto out_ssc;

    strcpy(card->driver, "at73c213");
    strcpy(card->shortname, board->shortname);
    sprintf(card->longname, "%s on irq %d", card->shortname, chip->irq);

    retval = snd_card_register(card);
    if (retval)
        goto out_ssc;

    dev_set_drvdata(&spi->dev, card);

    goto out;

out_ssc:
    ssc_free(chip->ssc);
out_card:
    snd_card_free(card);
out:
    return retval;
}

static int __devexit snd_at73c213_remove(struct spi_device *spi)
{
    struct snd_card *card = dev_get_drvdata(&spi->dev);
    struct snd_at73c213 *chip = card->private_data;
    int retval;

    /* Stop playback. */
    ssc_writel(chip->ssc->regs, CR, SSC_BIT(CR_TXDIS));

    /* Mute sound. */
    retval = snd_at73c213_write_reg(chip, DAC_LMPG, 0x3f);
    if (retval)
        goto out;
    retval = snd_at73c213_write_reg(chip, DAC_RMPG, 0x3f);
    if (retval)
        goto out;
    retval = snd_at73c213_write_reg(chip, DAC_LLOG, 0x3f);
    if (retval)
        goto out;
    retval = snd_at73c213_write_reg(chip, DAC_RLOG, 0x3f);
    if (retval)
        goto out;
    retval = snd_at73c213_write_reg(chip, DAC_LLIG, 0x11);
    if (retval)
        goto out;
    retval = snd_at73c213_write_reg(chip, DAC_RLIG, 0x11);
    if (retval)
        goto out;
    retval = snd_at73c213_write_reg(chip, DAC_AUXG, 0x11);
    if (retval)
        goto out;

    /* Turn off PA. */
    retval = snd_at73c213_write_reg(chip, PA_CTRL,
                    chip->reg_image[PA_CTRL] | 0x0f);
    if (retval)
        goto out;
    msleep(10);
    retval = snd_at73c213_write_reg(chip, PA_CTRL,
                    (1 << PA_CTRL_APALP) | 0x0f);
    if (retval)
        goto out;

    /* Turn off external DAC. */
    retval = snd_at73c213_write_reg(chip, DAC_CTRL, 0x0c);
    if (retval)
        goto out;
    msleep(2);
    retval = snd_at73c213_write_reg(chip, DAC_CTRL, 0x00);
    if (retval)
        goto out;

    /* Turn off master power. */
    retval = snd_at73c213_write_reg(chip, DAC_PRECH, 0x00);
    if (retval)
        goto out;

out:
    /* Stop DAC master clock. */
    clk_disable(chip->board->dac_clk);

    ssc_free(chip->ssc);
    snd_card_free(card);
    dev_set_drvdata(&spi->dev, NULL);

    return 0;
}

#ifdef CONFIG_PM
static int snd_at73c213_suspend(struct spi_device *spi, pm_message_t msg)
{
    struct snd_card *card = dev_get_drvdata(&spi->dev);
    struct snd_at73c213 *chip = card->private_data;

    ssc_writel(chip->ssc->regs, CR, SSC_BIT(CR_TXDIS));
    clk_disable(chip->board->dac_clk);

    return 0;
}

static int snd_at73c213_resume(struct spi_device *spi)
{
    struct snd_card *card = dev_get_drvdata(&spi->dev);
    struct snd_at73c213 *chip = card->private_data;

    clk_enable(chip->board->dac_clk);
    ssc_writel(chip->ssc->regs, CR, SSC_BIT(CR_TXEN));

    return 0;
}
#else
#define snd_at73c213_suspend NULL
#define snd_at73c213_resume NULL
#endif

static struct spi_driver at73c213_driver = {
    .driver     = {
        .name   = "at73c213",
    },
    .probe      = snd_at73c213_probe,
    .suspend    = snd_at73c213_suspend,
    .resume     = snd_at73c213_resume,
    .remove     = __devexit_p(snd_at73c213_remove),
};

module_spi_driver(at73c213_driver);

MODULE_AUTHOR("Hans-Christian Egtvedt <[email protected]>");
MODULE_DESCRIPTION("Sound driver for AT73C213 with Atmel SSC");
MODULE_LICENSE("GPL");