root/sound/soc/loongson/loongson_card.c
// SPDX-License-Identifier: GPL-2.0
//
// Loongson ASoC Audio Machine driver
//
// Copyright (C) 2023 Loongson Technology Corporation Limited
// Author: Yingkun Meng <mengyingkun@loongson.cn>
//

#include <linux/module.h>
#include <sound/soc.h>
#include <sound/soc-acpi.h>
#include <linux/acpi.h>
#include <linux/pci.h>
#include <sound/pcm_params.h>

static char codec_name[SND_ACPI_I2C_ID_LEN];

struct loongson_card_data {
        struct snd_soc_card snd_card;
        unsigned int mclk_fs;
};

static int loongson_card_hw_params(struct snd_pcm_substream *substream,
                                   struct snd_pcm_hw_params *params)
{
        struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
        struct loongson_card_data *ls_card = snd_soc_card_get_drvdata(rtd->card);
        struct snd_soc_dai *codec_dai = snd_soc_rtd_to_codec(rtd, 0);
        struct snd_soc_dai *cpu_dai = snd_soc_rtd_to_cpu(rtd, 0);
        int ret, mclk;

        if (!ls_card->mclk_fs)
                return 0;

        mclk = ls_card->mclk_fs * params_rate(params);
        ret = snd_soc_dai_set_sysclk(cpu_dai, 0, mclk, SND_SOC_CLOCK_OUT);
        if (ret < 0) {
                dev_err(codec_dai->dev, "cpu_dai clock not set\n");
                return ret;
        }

        ret = snd_soc_dai_set_sysclk(codec_dai, 0, mclk, SND_SOC_CLOCK_IN);
        if (ret < 0) {
                dev_err(codec_dai->dev, "codec_dai clock not set\n");
                return ret;
        }

        return 0;
}

static const struct snd_soc_ops loongson_ops = {
        .hw_params = loongson_card_hw_params,
};

SND_SOC_DAILINK_DEFS(analog,
        DAILINK_COMP_ARRAY(COMP_CPU("loongson-i2s")),
        DAILINK_COMP_ARRAY(COMP_EMPTY()),
        DAILINK_COMP_ARRAY(COMP_EMPTY()));

static struct snd_soc_dai_link loongson_dai_links[] = {
        {
                .name = "Loongson Audio Port",
                .stream_name = "Loongson Audio",
                .dai_fmt = SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_IB_NF
                        | SND_SOC_DAIFMT_CBC_CFC,
                SND_SOC_DAILINK_REG(analog),
                .ops = &loongson_ops,
        },
};

static struct acpi_device *loongson_card_acpi_find_device(struct snd_soc_card *card,
                                                          const char *name)
{
        struct fwnode_handle *fwnode = card->dev->fwnode;
        struct fwnode_reference_args args;
        int status;

        memset(&args, 0, sizeof(args));
        status = acpi_node_get_property_reference(fwnode, name, 0, &args);
        if (status || !is_acpi_device_node(args.fwnode)) {
                dev_err(card->dev, "No matching phy in ACPI table\n");
                return NULL;
        }

        return to_acpi_device_node(args.fwnode);
}

static int loongson_card_parse_acpi(struct loongson_card_data *data)
{
        struct snd_soc_card *card = &data->snd_card;
        const char *codec_dai_name;
        struct acpi_device *adev;
        struct device *phy_dev;
        int i;

        /* fixup platform name based on reference node */
        adev = loongson_card_acpi_find_device(card, "cpu");
        if (!adev)
                return -ENOENT;

        phy_dev = acpi_get_first_physical_node(adev);
        if (!phy_dev)
                return -EPROBE_DEFER;

        /* fixup codec name based on reference node */
        adev = loongson_card_acpi_find_device(card, "codec");
        if (!adev)
                return -ENOENT;
        snprintf(codec_name, sizeof(codec_name), "i2c-%s", acpi_dev_name(adev));

        device_property_read_string(card->dev, "codec-dai-name", &codec_dai_name);

        for (i = 0; i < card->num_links; i++) {
                loongson_dai_links[i].platforms->name = dev_name(phy_dev);
                loongson_dai_links[i].codecs->name = codec_name;
                loongson_dai_links[i].codecs->dai_name = codec_dai_name;
        }

        return 0;
}

static int loongson_card_parse_of(struct loongson_card_data *data)
{
        struct device_node *cpu, *codec;
        struct snd_soc_card *card = &data->snd_card;
        struct device *dev = card->dev;
        int ret, i;

        cpu = of_get_child_by_name(dev->of_node, "cpu");
        if (!cpu) {
                dev_err(dev, "platform property missing or invalid\n");
                return -EINVAL;
        }
        codec = of_get_child_by_name(dev->of_node, "codec");
        if (!codec) {
                dev_err(dev, "audio-codec property missing or invalid\n");
                of_node_put(cpu);
                return -EINVAL;
        }

        for (i = 0; i < card->num_links; i++) {
                ret = snd_soc_of_get_dlc(cpu, NULL, loongson_dai_links[i].cpus, 0);
                if (ret < 0) {
                        dev_err(dev, "getting cpu dlc error (%d)\n", ret);
                        goto err;
                }
                loongson_dai_links[i].platforms->of_node = loongson_dai_links[i].cpus->of_node;

                ret = snd_soc_of_get_dlc(codec, NULL, loongson_dai_links[i].codecs, 0);
                if (ret < 0) {
                        dev_err(dev, "getting codec dlc error (%d)\n", ret);
                        goto err;
                }
        }

        of_node_put(cpu);
        of_node_put(codec);

        return 0;

err:
        of_node_put(cpu);
        of_node_put(codec);
        return ret;
}

static int loongson_asoc_card_probe(struct platform_device *pdev)
{
        struct loongson_card_data *ls_priv;
        struct device *dev = &pdev->dev;
        struct snd_soc_card *card;
        int ret;

        ls_priv = devm_kzalloc(dev, sizeof(*ls_priv), GFP_KERNEL);
        if (!ls_priv)
                return -ENOMEM;

        card = &ls_priv->snd_card;

        card->dev = dev;
        card->owner = THIS_MODULE;
        card->dai_link = loongson_dai_links;
        card->num_links = ARRAY_SIZE(loongson_dai_links);
        snd_soc_card_set_drvdata(card, ls_priv);

        ret = device_property_read_string(dev, "model", &card->name);
        if (ret)
                return dev_err_probe(dev, ret, "Error parsing card name\n");

        ret = device_property_read_u32(dev, "mclk-fs", &ls_priv->mclk_fs);
        if (ret)
                return dev_err_probe(dev, ret, "Error parsing mclk-fs\n");

        ret = has_acpi_companion(dev) ? loongson_card_parse_acpi(ls_priv)
                                      : loongson_card_parse_of(ls_priv);
        if (ret)
                return dev_err_probe(dev, ret, "Error parsing acpi/of properties\n");

        return devm_snd_soc_register_card(dev, card);
}

static const struct of_device_id loongson_asoc_dt_ids[] = {
        { .compatible = "loongson,ls-audio-card" },
        { /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, loongson_asoc_dt_ids);

static struct platform_driver loongson_audio_driver = {
        .probe = loongson_asoc_card_probe,
        .driver = {
                .name = "loongson-asoc-card",
                .pm = &snd_soc_pm_ops,
                .of_match_table = loongson_asoc_dt_ids,
        },
};
module_platform_driver(loongson_audio_driver);

MODULE_DESCRIPTION("Loongson ASoc Sound Card driver");
MODULE_AUTHOR("Loongson Technology Corporation Limited");
MODULE_LICENSE("GPL");