sam9g20_wm8731.c

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/*
 * sam9g20_wm8731  --  SoC audio for AT91SAM9G20-based
 *          ATMEL AT91SAM9G20ek board.
 *
 *  Copyright (C) 2005 SAN People
 *  Copyright (C) 2008 Atmel
 *
 * Authors: Sedji Gaouaou <[email protected]>
 *
 * Based on ati_b1_wm8731.c by:
 * Frank Mandarino <[email protected]>
 * Copyright 2006 Endrelia Technologies Inc.
 * Based on corgi.c by:
 * Copyright 2005 Wolfson Microelectronics PLC.
 * Copyright 2005 Openedhand Ltd.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/clk.h>
#include <linux/timer.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/i2c.h>

#include <linux/atmel-ssc.h>

#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>

#include <asm/mach-types.h>
#include <mach/hardware.h>
#include <mach/gpio.h>

#include "../codecs/wm8731.h"
#include "atmel-pcm.h"
#include "atmel_ssc_dai.h"

#define MCLK_RATE 12000000

/*
 * As shipped the board does not have inputs.  However, it is relatively
 * straightforward to modify the board to hook them up so support is left
 * in the driver.
 */
#undef ENABLE_MIC_INPUT

static struct clk *mclk;

static int at91sam9g20ek_hw_params(struct snd_pcm_substream *substream,
    struct snd_pcm_hw_params *params)
{
    struct snd_soc_pcm_runtime *rtd = substream->private_data;
    struct snd_soc_dai *codec_dai = rtd->codec_dai;
    struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
    int ret;

    /* set codec DAI configuration */
    ret = snd_soc_dai_set_fmt(codec_dai, SND_SOC_DAIFMT_I2S |
        SND_SOC_DAIFMT_NB_NF | SND_SOC_DAIFMT_CBM_CFM);
    if (ret < 0)
        return ret;

    /* set cpu DAI configuration */
    ret = snd_soc_dai_set_fmt(cpu_dai, SND_SOC_DAIFMT_I2S |
        SND_SOC_DAIFMT_NB_NF | SND_SOC_DAIFMT_CBM_CFM);
    if (ret < 0)
        return ret;

    return 0;
}

static struct snd_soc_ops at91sam9g20ek_ops = {
    .hw_params = at91sam9g20ek_hw_params,
};

static int at91sam9g20ek_set_bias_level(struct snd_soc_card *card,
                    struct snd_soc_dapm_context *dapm,
                    enum snd_soc_bias_level level)
{
    static int mclk_on;
    int ret = 0;

    switch (level) {
    case SND_SOC_BIAS_ON:
    case SND_SOC_BIAS_PREPARE:
        if (!mclk_on)
            ret = clk_enable(mclk);
        if (ret == 0)
            mclk_on = 1;
        break;

    case SND_SOC_BIAS_OFF:
    case SND_SOC_BIAS_STANDBY:
        if (mclk_on)
            clk_disable(mclk);
        mclk_on = 0;
        break;
    }

    return ret;
}

static const struct snd_soc_dapm_widget at91sam9g20ek_dapm_widgets[] = {
    SND_SOC_DAPM_MIC("Int Mic", NULL),
    SND_SOC_DAPM_SPK("Ext Spk", NULL),
};

static const struct snd_soc_dapm_route intercon[] = {

    /* speaker connected to LHPOUT */
    {"Ext Spk", NULL, "LHPOUT"},

    /* mic is connected to Mic Jack, with WM8731 Mic Bias */
    {"MICIN", NULL, "Mic Bias"},
    {"Mic Bias", NULL, "Int Mic"},
};

/*
 * Logic for a wm8731 as connected on a at91sam9g20ek board.
 */
static int at91sam9g20ek_wm8731_init(struct snd_soc_pcm_runtime *rtd)
{
    struct snd_soc_codec *codec = rtd->codec;
    struct snd_soc_dai *codec_dai = rtd->codec_dai;
    struct snd_soc_dapm_context *dapm = &codec->dapm;
    int ret;

    printk(KERN_DEBUG
            "at91sam9g20ek_wm8731 "
            ": at91sam9g20ek_wm8731_init() called\n");

    ret = snd_soc_dai_set_sysclk(codec_dai, WM8731_SYSCLK_MCLK,
        MCLK_RATE, SND_SOC_CLOCK_IN);
    if (ret < 0) {
        printk(KERN_ERR "Failed to set WM8731 SYSCLK: %d\n", ret);
        return ret;
    }

    /* Add specific widgets */
    snd_soc_dapm_new_controls(dapm, at91sam9g20ek_dapm_widgets,
                  ARRAY_SIZE(at91sam9g20ek_dapm_widgets));
    /* Set up specific audio path interconnects */
    snd_soc_dapm_add_routes(dapm, intercon, ARRAY_SIZE(intercon));

    /* not connected */
    snd_soc_dapm_nc_pin(dapm, "RLINEIN");
    snd_soc_dapm_nc_pin(dapm, "LLINEIN");

#ifdef ENABLE_MIC_INPUT
    snd_soc_dapm_enable_pin(dapm, "Int Mic");
#else
    snd_soc_dapm_nc_pin(dapm, "Int Mic");
#endif

    /* always connected */
    snd_soc_dapm_enable_pin(dapm, "Ext Spk");

    return 0;
}

static struct snd_soc_dai_link at91sam9g20ek_dai = {
    .name = "WM8731",
    .stream_name = "WM8731 PCM",
    .cpu_dai_name = "atmel-ssc-dai.0",
    .codec_dai_name = "wm8731-hifi",
    .init = at91sam9g20ek_wm8731_init,
    .platform_name = "atmel-pcm-audio",
    .codec_name = "wm8731.0-001b",
    .ops = &at91sam9g20ek_ops,
};

static struct snd_soc_card snd_soc_at91sam9g20ek = {
    .name = "AT91SAMG20-EK",
    .owner = THIS_MODULE,
    .dai_link = &at91sam9g20ek_dai,
    .num_links = 1,
    .set_bias_level = at91sam9g20ek_set_bias_level,
};

static struct platform_device *at91sam9g20ek_snd_device;

static int __init at91sam9g20ek_init(void)
{
    struct clk *pllb;
    int ret;

    if (!(machine_is_at91sam9g20ek() || machine_is_at91sam9g20ek_2mmc()))
        return -ENODEV;

    ret = atmel_ssc_set_audio(0);
    if (ret != 0) {
        pr_err("Failed to set SSC 0 for audio: %d\n", ret);
        return ret;
    }

    /*
     * Codec MCLK is supplied by PCK0 - set it up.
     */
    mclk = clk_get(NULL, "pck0");
    if (IS_ERR(mclk)) {
        printk(KERN_ERR "ASoC: Failed to get MCLK\n");
        ret = PTR_ERR(mclk);
        goto err;
    }

    pllb = clk_get(NULL, "pllb");
    if (IS_ERR(pllb)) {
        printk(KERN_ERR "ASoC: Failed to get PLLB\n");
        ret = PTR_ERR(pllb);
        goto err_mclk;
    }
    ret = clk_set_parent(mclk, pllb);
    clk_put(pllb);
    if (ret != 0) {
        printk(KERN_ERR "ASoC: Failed to set MCLK parent\n");
        goto err_mclk;
    }

    clk_set_rate(mclk, MCLK_RATE);

    at91sam9g20ek_snd_device = platform_device_alloc("soc-audio", -1);
    if (!at91sam9g20ek_snd_device) {
        printk(KERN_ERR "ASoC: Platform device allocation failed\n");
        ret = -ENOMEM;
        goto err_mclk;
    }

    platform_set_drvdata(at91sam9g20ek_snd_device,
            &snd_soc_at91sam9g20ek);

    ret = platform_device_add(at91sam9g20ek_snd_device);
    if (ret) {
        printk(KERN_ERR "ASoC: Platform device allocation failed\n");
        goto err_device_add;
    }

    return ret;

err_device_add:
    platform_device_put(at91sam9g20ek_snd_device);
err_mclk:
    clk_put(mclk);
    mclk = NULL;
err:
    return ret;
}

static void __exit at91sam9g20ek_exit(void)
{
    platform_device_unregister(at91sam9g20ek_snd_device);
    at91sam9g20ek_snd_device = NULL;
    clk_put(mclk);
    mclk = NULL;
}

module_init(at91sam9g20ek_init);
module_exit(at91sam9g20ek_exit);

/* Module information */
MODULE_AUTHOR("Sedji Gaouaou <[email protected]>");
MODULE_DESCRIPTION("ALSA SoC AT91SAM9G20EK_WM8731");
MODULE_LICENSE("GPL");