/* sound/soc/samsung/s3c24xx_simtec.c
 *
 * Copyright 2009 Simtec Electronics
 *
 * 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/gpio.h>
#include <linux/clk.h>
#include <linux/module.h>

#include <sound/soc.h>

#include <linux/platform_data/asoc-s3c24xx_simtec.h>

#include "s3c24xx-i2s.h"
#include "s3c24xx_simtec.h"

static struct s3c24xx_audio_simtec_pdata *pdata;
static struct clk *xtal_clk;

static int spk_gain;
static int spk_unmute;

/**
 * speaker_gain_get - read the speaker gain setting.
 * @kcontrol: The control for the speaker gain.
 * @ucontrol: The value that needs to be updated.
 *
 * Read the value for the AMP gain control.
 */
static int speaker_gain_get(struct snd_kcontrol *kcontrol,
                            struct snd_ctl_elem_value *ucontrol)
{
        ucontrol->value.integer.value[0] = spk_gain;
        return 0;
}

/**
 * speaker_gain_set - set the value of the speaker amp gain
 * @value: The value to write.
 */
static void speaker_gain_set(int value)
{
        gpio_set_value_cansleep(pdata->amp_gain[0], value & 1);
        gpio_set_value_cansleep(pdata->amp_gain[1], value >> 1);
}

/**
 * speaker_gain_put - set the speaker gain setting.
 * @kcontrol: The control for the speaker gain.
 * @ucontrol: The value that needs to be set.
 *
 * Set the value of the speaker gain from the specified
 * @ucontrol setting.
 *
 * Note, if the speaker amp is muted, then we do not set a gain value
 * as at-least one of the ICs that is fitted will try and power up even
 * if the main control is set to off.
 */
static int speaker_gain_put(struct snd_kcontrol *kcontrol,
                            struct snd_ctl_elem_value *ucontrol)
{
        int value = ucontrol->value.integer.value[0];

        spk_gain = value;

        if (!spk_unmute)
                speaker_gain_set(value);

        return 0;
}

static const struct snd_kcontrol_new amp_gain_controls[] = {
        SOC_SINGLE_EXT("Speaker Gain", 0, 0, 3, 0,
                       speaker_gain_get, speaker_gain_put),
};

/**
 * spk_unmute_state - set the unmute state of the speaker
 * @to: zero to unmute, non-zero to ununmute.
 */
static void spk_unmute_state(int to)
{
        pr_debug("%s: to=%d\n", __func__, to);

        spk_unmute = to;
        gpio_set_value(pdata->amp_gpio, to);

        /* if we're umuting, also re-set the gain */
        if (to && pdata->amp_gain[0] > 0)
                speaker_gain_set(spk_gain);
}

/**
 * speaker_unmute_get - read the speaker unmute setting.
 * @kcontrol: The control for the speaker gain.
 * @ucontrol: The value that needs to be updated.
 *
 * Read the value for the AMP gain control.
 */
static int speaker_unmute_get(struct snd_kcontrol *kcontrol,
                            struct snd_ctl_elem_value *ucontrol)
{
        ucontrol->value.integer.value[0] = spk_unmute;
        return 0;
}

/**
 * speaker_unmute_put - set the speaker unmute setting.
 * @kcontrol: The control for the speaker gain.
 * @ucontrol: The value that needs to be set.
 *
 * Set the value of the speaker gain from the specified
 * @ucontrol setting.
 */
static int speaker_unmute_put(struct snd_kcontrol *kcontrol,
                            struct snd_ctl_elem_value *ucontrol)
{
        spk_unmute_state(ucontrol->value.integer.value[0]);
        return 0;
}

/* This is added as a manual control as the speaker amps create clicks
 * when their power state is changed, which are far more noticeable than
 * anything produced by the CODEC itself.
 */
static const struct snd_kcontrol_new amp_unmute_controls[] = {
        SOC_SINGLE_EXT("Speaker Switch", 0, 0, 1, 0,
                       speaker_unmute_get, speaker_unmute_put),
};

void simtec_audio_init(struct snd_soc_pcm_runtime *rtd)
{
        struct snd_soc_card *card = rtd->card;

        if (pdata->amp_gpio > 0) {
                pr_debug("%s: adding amp routes\n", __func__);

                snd_soc_add_card_controls(card, amp_unmute_controls,
                                     ARRAY_SIZE(amp_unmute_controls));
        }

        if (pdata->amp_gain[0] > 0) {
                pr_debug("%s: adding amp controls\n", __func__);
                snd_soc_add_card_controls(card, amp_gain_controls,
                                     ARRAY_SIZE(amp_gain_controls));
        }
}
EXPORT_SYMBOL_GPL(simtec_audio_init);

#define CODEC_CLOCK 12000000

/**
 * simtec_hw_params - update hardware parameters
 * @substream: The audio substream instance.
 * @params: The parameters requested.
 *
 * Update the codec data routing and configuration  settings
 * from the supplied data.
 */
static int simtec_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;

        ret = snd_soc_dai_set_sysclk(codec_dai, 0,
                                     CODEC_CLOCK, SND_SOC_CLOCK_IN);
        if (ret) {
                pr_err( "%s: failed setting codec sysclk\n", __func__);
                return ret;
        }

        if (pdata->use_mpllin) {
                ret = snd_soc_dai_set_sysclk(cpu_dai, S3C24XX_CLKSRC_MPLL,
                                             0, SND_SOC_CLOCK_OUT);

                if (ret) {
                        pr_err("%s: failed to set MPLLin as clksrc\n",
                               __func__);
                        return ret;
                }
        }

        if (pdata->output_cdclk) {
                int cdclk_scale;

                cdclk_scale = clk_get_rate(xtal_clk) / CODEC_CLOCK;
                cdclk_scale--;

                ret = snd_soc_dai_set_clkdiv(cpu_dai, S3C24XX_DIV_PRESCALER,
                                             cdclk_scale);
        }

        return 0;
}

static int simtec_call_startup(struct s3c24xx_audio_simtec_pdata *pd)
{
        /* call any board supplied startup code, this currently only
         * covers the bast/vr1000 which have a CPLD in the way of the
         * LRCLK */
        if (pd->startup)
                pd->startup();

        return 0;
}

static struct snd_soc_ops simtec_snd_ops = {
        .hw_params      = simtec_hw_params,
};

/**
 * attach_gpio_amp - get and configure the necessary gpios
 * @dev: The device we're probing.
 * @pd: The platform data supplied by the board.
 *
 * If there is a GPIO based amplifier attached to the board, claim
 * the necessary GPIO lines for it, and set default values.
 */
static int attach_gpio_amp(struct device *dev,
                           struct s3c24xx_audio_simtec_pdata *pd)
{
        int ret;

        /* attach gpio amp gain (if any) */
        if (pdata->amp_gain[0] > 0) {
                ret = gpio_request(pd->amp_gain[0], "gpio-amp-gain0");
                if (ret) {
                        dev_err(dev, "cannot get amp gpio gain0\n");
                        return ret;
                }

                ret = gpio_request(pd->amp_gain[1], "gpio-amp-gain1");
                if (ret) {
                        dev_err(dev, "cannot get amp gpio gain1\n");
                        gpio_free(pdata->amp_gain[0]);
                        return ret;
                }

                gpio_direction_output(pd->amp_gain[0], 0);
                gpio_direction_output(pd->amp_gain[1], 0);
        }

        /* note, currently we assume GPA0 isn't valid amp */
        if (pdata->amp_gpio > 0) {
                ret = gpio_request(pd->amp_gpio, "gpio-amp");
                if (ret) {
                        dev_err(dev, "cannot get amp gpio %d (%d)\n",
                                pd->amp_gpio, ret);
                        goto err_amp;
                }

                /* set the amp off at startup */
                spk_unmute_state(0);
        }

        return 0;

err_amp:
        if (pd->amp_gain[0] > 0) {
                gpio_free(pd->amp_gain[0]);
                gpio_free(pd->amp_gain[1]);
        }

        return ret;
}

static void detach_gpio_amp(struct s3c24xx_audio_simtec_pdata *pd)
{
        if (pd->amp_gain[0] > 0) {
                gpio_free(pd->amp_gain[0]);
                gpio_free(pd->amp_gain[1]);
        }

        if (pd->amp_gpio > 0)
                gpio_free(pd->amp_gpio);
}

#ifdef CONFIG_PM
static int simtec_audio_resume(struct device *dev)
{
        simtec_call_startup(pdata);
        return 0;
}

const struct dev_pm_ops simtec_audio_pmops = {
        .resume = simtec_audio_resume,
};
EXPORT_SYMBOL_GPL(simtec_audio_pmops);
#endif

int simtec_audio_core_probe(struct platform_device *pdev,
                            struct snd_soc_card *card)
{
        struct platform_device *snd_dev;
        int ret;

        card->dai_link->ops = &simtec_snd_ops;
        card->dai_link->dai_fmt = SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_NB_NF |
                                  SND_SOC_DAIFMT_CBM_CFM;

        pdata = pdev->dev.platform_data;
        if (!pdata) {
                dev_err(&pdev->dev, "no platform data supplied\n");
                return -EINVAL;
        }

        simtec_call_startup(pdata);

        xtal_clk = clk_get(&pdev->dev, "xtal");
        if (IS_ERR(xtal_clk)) {
                dev_err(&pdev->dev, "could not get clkout0\n");
                return -EINVAL;
        }

        dev_info(&pdev->dev, "xtal rate is %ld\n", clk_get_rate(xtal_clk));

        ret = attach_gpio_amp(&pdev->dev, pdata);
        if (ret)
                goto err_clk;

        snd_dev = platform_device_alloc("soc-audio", -1);
        if (!snd_dev) {
                dev_err(&pdev->dev, "failed to alloc soc-audio devicec\n");
                ret = -ENOMEM;
                goto err_gpio;
        }

        platform_set_drvdata(snd_dev, card);

        ret = platform_device_add(snd_dev);
        if (ret) {
                dev_err(&pdev->dev, "failed to add soc-audio dev\n");
                goto err_pdev;
        }

        platform_set_drvdata(pdev, snd_dev);
        return 0;

err_pdev:
        platform_device_put(snd_dev);

err_gpio:
        detach_gpio_amp(pdata);

err_clk:
        clk_put(xtal_clk);
        return ret;
}
EXPORT_SYMBOL_GPL(simtec_audio_core_probe);

int simtec_audio_remove(struct platform_device *pdev)
{
        struct platform_device *snd_dev = platform_get_drvdata(pdev);

        platform_device_unregister(snd_dev);

        detach_gpio_amp(pdata);
        clk_put(xtal_clk);
        return 0;
}
EXPORT_SYMBOL_GPL(simtec_audio_remove);

MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
MODULE_DESCRIPTION("ALSA SoC Simtec Audio common support");
MODULE_LICENSE("GPL");