migor.c

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/*
 * ALSA SoC driver for Migo-R
 *
 * Copyright (C) 2009-2010 Guennadi Liakhovetski <[email protected]>
 *
 * 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.
 */

#include <linux/clkdev.h>
#include <linux/device.h>
#include <linux/firmware.h>
#include <linux/module.h>

#include <asm/clock.h>

#include <cpu/sh7722.h>

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

#include "../codecs/wm8978.h"
#include "siu.h"

/* Default 8000Hz sampling frequency */
static unsigned long codec_freq = 8000 * 512;

static unsigned int use_count;

/* External clock, sourced from the codec at the SIUMCKB pin */
static unsigned long siumckb_recalc(struct clk *clk)
{
    return codec_freq;
}

static struct sh_clk_ops siumckb_clk_ops = {
    .recalc = siumckb_recalc,
};

static struct clk siumckb_clk = {
    .ops        = &siumckb_clk_ops,
    .rate       = 0, /* initialised at run-time */
};

static struct clk_lookup *siumckb_lookup;

static int migor_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;
    int ret;
    unsigned int rate = params_rate(params);

    ret = snd_soc_dai_set_sysclk(codec_dai, WM8978_PLL, 13000000,
                     SND_SOC_CLOCK_IN);
    if (ret < 0)
        return ret;

    ret = snd_soc_dai_set_clkdiv(codec_dai, WM8978_OPCLKRATE, rate * 512);
    if (ret < 0)
        return ret;

    ret = snd_soc_dai_set_fmt(codec_dai, SND_SOC_DAIFMT_NB_IF |
                  SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_CBS_CFS);
    if (ret < 0)
        return ret;

    ret = snd_soc_dai_set_fmt(rtd->cpu_dai, SND_SOC_DAIFMT_NB_IF |
                  SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_CBS_CFS);
    if (ret < 0)
        return ret;

    codec_freq = rate * 512;
    /*
     * This propagates the parent frequency change to children and
     * recalculates the frequency table
     */
    clk_set_rate(&siumckb_clk, codec_freq);
    dev_dbg(codec_dai->dev, "%s: configure %luHz\n", __func__, codec_freq);

    ret = snd_soc_dai_set_sysclk(rtd->cpu_dai, SIU_CLKB_EXT,
                     codec_freq / 2, SND_SOC_CLOCK_IN);

    if (!ret)
        use_count++;

    return ret;
}

static int migor_hw_free(struct snd_pcm_substream *substream)
{
    struct snd_soc_pcm_runtime *rtd = substream->private_data;
    struct snd_soc_dai *codec_dai = rtd->codec_dai;

    if (use_count) {
        use_count--;

        if (!use_count)
            snd_soc_dai_set_sysclk(codec_dai, WM8978_PLL, 0,
                           SND_SOC_CLOCK_IN);
    } else {
        dev_dbg(codec_dai->dev, "Unbalanced hw_free!\n");
    }

    return 0;
}

static struct snd_soc_ops migor_dai_ops = {
    .hw_params = migor_hw_params,
    .hw_free = migor_hw_free,
};

static const struct snd_soc_dapm_widget migor_dapm_widgets[] = {
    SND_SOC_DAPM_HP("Headphone", NULL),
    SND_SOC_DAPM_MIC("Onboard Microphone", NULL),
    SND_SOC_DAPM_MIC("External Microphone", NULL),
};

static const struct snd_soc_dapm_route audio_map[] = {
    /* Headphone output connected to LHP/RHP, enable OUT4 for VMID */
    { "Headphone", NULL,  "OUT4 VMID" },
    { "OUT4 VMID", NULL,  "LHP" },
    { "OUT4 VMID", NULL,  "RHP" },

    /* On-board microphone */
    { "RMICN", NULL, "Mic Bias" },
    { "RMICP", NULL, "Mic Bias" },
    { "Mic Bias", NULL, "Onboard Microphone" },

    /* External microphone */
    { "LMICN", NULL, "Mic Bias" },
    { "LMICP", NULL, "Mic Bias" },
    { "Mic Bias", NULL, "External Microphone" },
};

static int migor_dai_init(struct snd_soc_pcm_runtime *rtd)
{
    struct snd_soc_codec *codec = rtd->codec;
    struct snd_soc_dapm_context *dapm = &codec->dapm;

    snd_soc_dapm_new_controls(dapm, migor_dapm_widgets,
                  ARRAY_SIZE(migor_dapm_widgets));

    snd_soc_dapm_add_routes(dapm, audio_map, ARRAY_SIZE(audio_map));

    return 0;
}

/* migor digital audio interface glue - connects codec <--> CPU */
static struct snd_soc_dai_link migor_dai = {
    .name = "wm8978",
    .stream_name = "WM8978",
    .cpu_dai_name = "siu-i2s-dai",
    .codec_dai_name = "wm8978-hifi",
    .platform_name = "siu-pcm-audio",
    .codec_name = "wm8978.0-001a",
    .ops = &migor_dai_ops,
    .init = migor_dai_init,
};

/* migor audio machine driver */
static struct snd_soc_card snd_soc_migor = {
    .name = "Migo-R",
    .owner = THIS_MODULE,
    .dai_link = &migor_dai,
    .num_links = 1,
};

static struct platform_device *migor_snd_device;

static int __init migor_init(void)
{
    int ret;

    ret = clk_register(&siumckb_clk);
    if (ret < 0)
        return ret;

    siumckb_lookup = clkdev_alloc(&siumckb_clk, "siumckb_clk", NULL);
    if (!siumckb_lookup) {
        ret = -ENOMEM;
        goto eclkdevalloc;
    }
    clkdev_add(siumckb_lookup);

    /* Port number used on this machine: port B */
    migor_snd_device = platform_device_alloc("soc-audio", 1);
    if (!migor_snd_device) {
        ret = -ENOMEM;
        goto epdevalloc;
    }

    platform_set_drvdata(migor_snd_device, &snd_soc_migor);

    ret = platform_device_add(migor_snd_device);
    if (ret)
        goto epdevadd;

    return 0;

epdevadd:
    platform_device_put(migor_snd_device);
epdevalloc:
    clkdev_drop(siumckb_lookup);
eclkdevalloc:
    clk_unregister(&siumckb_clk);
    return ret;
}

static void __exit migor_exit(void)
{
    clkdev_drop(siumckb_lookup);
    clk_unregister(&siumckb_clk);
    platform_device_unregister(migor_snd_device);
}

module_init(migor_init);
module_exit(migor_exit);

MODULE_AUTHOR("Guennadi Liakhovetski <[email protected]>");
MODULE_DESCRIPTION("ALSA SoC Migor");
MODULE_LICENSE("GPL v2");