// SPDX-License-Identifier: GPL-2.0
//
// ASoC audio graph sound card support
//
// Copyright (C) 2016 Renesas Solutions Corp.
// Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
//
// based on ${LINUX}/sound/soc/generic/simple-card.c

#include <linux/clk.h>
#include <linux/device.h>
#include <linux/gpio.h>
#include <linux/gpio/consumer.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_gpio.h>
#include <linux/of_graph.h>
#include <linux/platform_device.h>
#include <linux/string.h>
#include <sound/graph_card.h>

#define DPCM_SELECTABLE 1

static int graph_outdrv_event(struct snd_soc_dapm_widget *w,
                              struct snd_kcontrol *kcontrol,
                              int event)
{
        struct snd_soc_dapm_context *dapm = w->dapm;
        struct asoc_simple_priv *priv = snd_soc_card_get_drvdata(dapm->card);

        switch (event) {
        case SND_SOC_DAPM_POST_PMU:
                gpiod_set_value_cansleep(priv->pa_gpio, 1);
                break;
        case SND_SOC_DAPM_PRE_PMD:
                gpiod_set_value_cansleep(priv->pa_gpio, 0);
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static const struct snd_soc_dapm_widget graph_dapm_widgets[] = {
        SND_SOC_DAPM_OUT_DRV_E("Amplifier", SND_SOC_NOPM,
                               0, 0, NULL, 0, graph_outdrv_event,
                               SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD),
};

static const struct snd_soc_ops graph_ops = {
        .startup        = asoc_simple_startup,
        .shutdown       = asoc_simple_shutdown,
        .hw_params      = asoc_simple_hw_params,
};

static int graph_get_dai_id(struct device_node *ep)
{
        struct device_node *node;
        struct device_node *endpoint;
        struct of_endpoint info;
        int i, id;
        const u32 *reg;
        int ret;

        /* use driver specified DAI ID if exist */
        ret = snd_soc_get_dai_id(ep);
        if (ret != -ENOTSUPP)
                return ret;

        /* use endpoint/port reg if exist */
        ret = of_graph_parse_endpoint(ep, &info);
        if (ret == 0) {
                /*
                 * Because it will count port/endpoint if it doesn't have "reg".
                 * But, we can't judge whether it has "no reg", or "reg = <0>"
                 * only of_graph_parse_endpoint().
                 * We need to check "reg" property
                 */
                if (of_get_property(ep,   "reg", NULL))
                        return info.id;

                node = of_get_parent(ep);
                reg = of_get_property(node, "reg", NULL);
                of_node_put(node);
                if (reg)
                        return info.port;
        }
        node = of_graph_get_port_parent(ep);

        /*
         * Non HDMI sound case, counting port/endpoint on its DT
         * is enough. Let's count it.
         */
        i = 0;
        id = -1;
        for_each_endpoint_of_node(node, endpoint) {
                if (endpoint == ep)
                        id = i;
                i++;
        }

        of_node_put(node);

        if (id < 0)
                return -ENODEV;

        return id;
}

static bool soc_component_is_pcm(struct snd_soc_dai_link_component *dlc)
{
        struct snd_soc_dai *dai = snd_soc_find_dai_with_mutex(dlc);

        if (dai && (dai->component->driver->pcm_construct ||
                    dai->driver->pcm_new))
                return true;

        return false;
}

static int asoc_simple_parse_dai(struct device_node *ep,
                                 struct snd_soc_dai_link_component *dlc,
                                 int *is_single_link)
{
        struct device_node *node;
        struct of_phandle_args args;
        int ret;

        if (!ep)
                return 0;

        node = of_graph_get_port_parent(ep);

        /* Get dai->name */
        args.np         = node;
        args.args[0]    = graph_get_dai_id(ep);
        args.args_count = (of_graph_get_endpoint_count(node) > 1);

        /*
         * FIXME
         *
         * Here, dlc->dai_name is pointer to CPU/Codec DAI name.
         * If user unbinded CPU or Codec driver, but not for Sound Card,
         * dlc->dai_name is keeping unbinded CPU or Codec
         * driver's pointer.
         *
         * If user re-bind CPU or Codec driver again, ALSA SoC will try
         * to rebind Card via snd_soc_try_rebind_card(), but because of
         * above reason, it might can't bind Sound Card.
         * Because Sound Card is pointing to released dai_name pointer.
         *
         * To avoid this rebind Card issue,
         * 1) It needs to alloc memory to keep dai_name eventhough
         *    CPU or Codec driver was unbinded, or
         * 2) user need to rebind Sound Card everytime
         *    if he unbinded CPU or Codec.
         */
        ret = snd_soc_get_dai_name(&args, &dlc->dai_name);
        if (ret < 0)
                return ret;

        dlc->of_node = node;

        if (is_single_link)
                *is_single_link = of_graph_get_endpoint_count(node) == 1;

        return 0;
}

static void graph_parse_convert(struct device *dev,
                                struct device_node *ep,
                                struct asoc_simple_data *adata)
{
        struct device_node *top = dev->of_node;
        struct device_node *port = of_get_parent(ep);
        struct device_node *ports = of_get_parent(port);
        struct device_node *node = of_graph_get_port_parent(ep);

        asoc_simple_parse_convert(top,   NULL,   adata);
        if (of_node_name_eq(ports, "ports"))
                asoc_simple_parse_convert(ports, NULL, adata);
        asoc_simple_parse_convert(port,  NULL,   adata);
        asoc_simple_parse_convert(ep,    NULL,   adata);

        of_node_put(port);
        of_node_put(ports);
        of_node_put(node);
}

static void graph_parse_mclk_fs(struct device_node *top,
                                struct device_node *ep,
                                struct simple_dai_props *props)
{
        struct device_node *port        = of_get_parent(ep);
        struct device_node *ports       = of_get_parent(port);

        of_property_read_u32(top,       "mclk-fs", &props->mclk_fs);
        if (of_node_name_eq(ports, "ports"))
                of_property_read_u32(ports, "mclk-fs", &props->mclk_fs);
        of_property_read_u32(port,      "mclk-fs", &props->mclk_fs);
        of_property_read_u32(ep,        "mclk-fs", &props->mclk_fs);

        of_node_put(port);
        of_node_put(ports);
}

static int graph_parse_node(struct asoc_simple_priv *priv,
                            struct device_node *ep,
                            struct link_info *li,
                            int *cpu)
{
        struct device *dev = simple_priv_to_dev(priv);
        struct device_node *top = dev->of_node;
        struct snd_soc_dai_link *dai_link = simple_priv_to_link(priv, li->link);
        struct simple_dai_props *dai_props = simple_priv_to_props(priv, li->link);
        struct snd_soc_dai_link_component *dlc;
        struct asoc_simple_dai *dai;
        int ret;

        if (cpu) {
                dlc = asoc_link_to_cpu(dai_link, 0);
                dai = simple_props_to_dai_cpu(dai_props, 0);
        } else {
                dlc = asoc_link_to_codec(dai_link, 0);
                dai = simple_props_to_dai_codec(dai_props, 0);
        }

        graph_parse_mclk_fs(top, ep, dai_props);

        ret = asoc_simple_parse_dai(ep, dlc, cpu);
        if (ret < 0)
                return ret;

        ret = asoc_simple_parse_tdm(ep, dai);
        if (ret < 0)
                return ret;

        ret = asoc_simple_parse_clk(dev, ep, dai, dlc);
        if (ret < 0)
                return ret;

        return 0;
}

static int graph_link_init(struct asoc_simple_priv *priv,
                           struct device_node *cpu_ep,
                           struct device_node *codec_ep,
                           struct link_info *li,
                           char *name)
{
        struct device *dev = simple_priv_to_dev(priv);
        struct snd_soc_dai_link *dai_link = simple_priv_to_link(priv, li->link);
        int ret;

        ret = asoc_simple_parse_daifmt(dev, cpu_ep, codec_ep,
                                       NULL, &dai_link->dai_fmt);
        if (ret < 0)
                return ret;

        dai_link->init          = asoc_simple_dai_init;
        dai_link->ops           = &graph_ops;
        if (priv->ops)
                dai_link->ops   = priv->ops;

        return asoc_simple_set_dailink_name(dev, dai_link, name);
}

static int graph_dai_link_of_dpcm(struct asoc_simple_priv *priv,
                                  struct device_node *cpu_ep,
                                  struct device_node *codec_ep,
                                  struct link_info *li)
{
        struct device *dev = simple_priv_to_dev(priv);
        struct snd_soc_dai_link *dai_link = simple_priv_to_link(priv, li->link);
        struct simple_dai_props *dai_props = simple_priv_to_props(priv, li->link);
        struct device_node *top = dev->of_node;
        struct device_node *ep = li->cpu ? cpu_ep : codec_ep;
        char dai_name[64];
        int ret;

        dev_dbg(dev, "link_of DPCM (%pOF)\n", ep);

        if (li->cpu) {
                struct snd_soc_card *card = simple_priv_to_card(priv);
                struct snd_soc_dai_link_component *cpus = asoc_link_to_cpu(dai_link, 0);
                struct snd_soc_dai_link_component *platforms = asoc_link_to_platform(dai_link, 0);
                int is_single_links = 0;

                /* Codec is dummy */

                /* FE settings */
                dai_link->dynamic               = 1;
                dai_link->dpcm_merged_format    = 1;

                ret = graph_parse_node(priv, cpu_ep, li, &is_single_links);
                if (ret)
                        return ret;

                snprintf(dai_name, sizeof(dai_name),
                         "fe.%pOFP.%s", cpus->of_node, cpus->dai_name);
                /*
                 * In BE<->BE connections it is not required to create
                 * PCM devices at CPU end of the dai link and thus 'no_pcm'
                 * flag needs to be set. It is useful when there are many
                 * BE components and some of these have to be connected to
                 * form a valid audio path.
                 *
                 * For example: FE <-> BE1 <-> BE2 <-> ... <-> BEn where
                 * there are 'n' BE components in the path.
                 */
                if (card->component_chaining && !soc_component_is_pcm(cpus))
                        dai_link->no_pcm = 1;

                asoc_simple_canonicalize_cpu(cpus, is_single_links);
                asoc_simple_canonicalize_platform(platforms, cpus);
        } else {
                struct snd_soc_codec_conf *cconf = simple_props_to_codec_conf(dai_props, 0);
                struct snd_soc_dai_link_component *codecs = asoc_link_to_codec(dai_link, 0);
                struct device_node *port;
                struct device_node *ports;

                /* CPU is dummy */

                /* BE settings */
                dai_link->no_pcm                = 1;
                dai_link->be_hw_params_fixup    = asoc_simple_be_hw_params_fixup;

                ret = graph_parse_node(priv, codec_ep, li, NULL);
                if (ret < 0)
                        return ret;

                snprintf(dai_name, sizeof(dai_name),
                         "be.%pOFP.%s", codecs->of_node, codecs->dai_name);

                /* check "prefix" from top node */
                port = of_get_parent(ep);
                ports = of_get_parent(port);
                snd_soc_of_parse_node_prefix(top, cconf, codecs->of_node,
                                              "prefix");
                if (of_node_name_eq(ports, "ports"))
                        snd_soc_of_parse_node_prefix(ports, cconf, codecs->of_node, "prefix");
                snd_soc_of_parse_node_prefix(port, cconf, codecs->of_node,
                                             "prefix");

                of_node_put(ports);
                of_node_put(port);
        }

        graph_parse_convert(dev, ep, &dai_props->adata);

        snd_soc_dai_link_set_capabilities(dai_link);

        ret = graph_link_init(priv, cpu_ep, codec_ep, li, dai_name);

        li->link++;

        return ret;
}

static int graph_dai_link_of(struct asoc_simple_priv *priv,
                             struct device_node *cpu_ep,
                             struct device_node *codec_ep,
                             struct link_info *li)
{
        struct device *dev = simple_priv_to_dev(priv);
        struct snd_soc_dai_link *dai_link = simple_priv_to_link(priv, li->link);
        struct snd_soc_dai_link_component *cpus = asoc_link_to_cpu(dai_link, 0);
        struct snd_soc_dai_link_component *codecs = asoc_link_to_codec(dai_link, 0);
        struct snd_soc_dai_link_component *platforms = asoc_link_to_platform(dai_link, 0);
        char dai_name[64];
        int ret, is_single_links = 0;

        dev_dbg(dev, "link_of (%pOF)\n", cpu_ep);

        ret = graph_parse_node(priv, cpu_ep, li, &is_single_links);
        if (ret < 0)
                return ret;

        ret = graph_parse_node(priv, codec_ep, li, NULL);
        if (ret < 0)
                return ret;

        snprintf(dai_name, sizeof(dai_name),
                 "%s-%s", cpus->dai_name, codecs->dai_name);

        asoc_simple_canonicalize_cpu(cpus, is_single_links);
        asoc_simple_canonicalize_platform(platforms, cpus);

        ret = graph_link_init(priv, cpu_ep, codec_ep, li, dai_name);
        if (ret < 0)
                return ret;

        li->link++;

        return 0;
}

static inline bool parse_as_dpcm_link(struct asoc_simple_priv *priv,
                                      struct device_node *codec_port,
                                      struct asoc_simple_data *adata)
{
        if (priv->force_dpcm)
                return true;

        if (!priv->dpcm_selectable)
                return false;

        /*
         * It is DPCM
         * if Codec port has many endpoints,
         * or has convert-xxx property
         */
        if ((of_get_child_count(codec_port) > 1) ||
            (adata->convert_rate || adata->convert_channels))
                return true;

        return false;
}

static int __graph_for_each_link(struct asoc_simple_priv *priv,
                        struct link_info *li,
                        int (*func_noml)(struct asoc_simple_priv *priv,
                                         struct device_node *cpu_ep,
                                         struct device_node *codec_ep,
                                         struct link_info *li),
                        int (*func_dpcm)(struct asoc_simple_priv *priv,
                                         struct device_node *cpu_ep,
                                         struct device_node *codec_ep,
                                         struct link_info *li))
{
        struct of_phandle_iterator it;
        struct device *dev = simple_priv_to_dev(priv);
        struct device_node *node = dev->of_node;
        struct device_node *cpu_port;
        struct device_node *cpu_ep;
        struct device_node *codec_ep;
        struct device_node *codec_port;
        struct device_node *codec_port_old = NULL;
        struct asoc_simple_data adata;
        int rc, ret = 0;

        /* loop for all listed CPU port */
        of_for_each_phandle(&it, rc, node, "dais", NULL, 0) {
                cpu_port = it.node;
                cpu_ep   = NULL;

                /* loop for all CPU endpoint */
                while (1) {
                        cpu_ep = of_get_next_child(cpu_port, cpu_ep);
                        if (!cpu_ep)
                                break;

                        /* get codec */
                        codec_ep = of_graph_get_remote_endpoint(cpu_ep);
                        codec_port = of_get_parent(codec_ep);

                        /* get convert-xxx property */
                        memset(&adata, 0, sizeof(adata));
                        graph_parse_convert(dev, codec_ep, &adata);
                        graph_parse_convert(dev, cpu_ep,   &adata);

                        /* check if link requires DPCM parsing */
                        if (parse_as_dpcm_link(priv, codec_port, &adata)) {
                                /*
                                 * Codec endpoint can be NULL for pluggable audio HW.
                                 * Platform DT can populate the Codec endpoint depending on the
                                 * plugged HW.
                                 */
                                /* Do it all CPU endpoint, and 1st Codec endpoint */
                                if (li->cpu ||
                                    ((codec_port_old != codec_port) && codec_ep))
                                        ret = func_dpcm(priv, cpu_ep, codec_ep, li);
                        /* else normal sound */
                        } else {
                                if (li->cpu)
                                        ret = func_noml(priv, cpu_ep, codec_ep, li);
                        }

                        of_node_put(codec_ep);
                        of_node_put(codec_port);

                        if (ret < 0)
                                return ret;

                        codec_port_old = codec_port;
                }
        }

        return 0;
}

static int graph_for_each_link(struct asoc_simple_priv *priv,
                               struct link_info *li,
                               int (*func_noml)(struct asoc_simple_priv *priv,
                                                struct device_node *cpu_ep,
                                                struct device_node *codec_ep,
                                                struct link_info *li),
                               int (*func_dpcm)(struct asoc_simple_priv *priv,
                                                struct device_node *cpu_ep,
                                                struct device_node *codec_ep,
                                                struct link_info *li))
{
        int ret;
        /*
         * Detect all CPU first, and Detect all Codec 2nd.
         *
         * In Normal sound case, all DAIs are detected
         * as "CPU-Codec".
         *
         * In DPCM sound case,
         * all CPUs   are detected as "CPU-dummy", and
         * all Codecs are detected as "dummy-Codec".
         * To avoid random sub-device numbering,
         * detect "dummy-Codec" in last;
         */
        for (li->cpu = 1; li->cpu >= 0; li->cpu--) {
                ret = __graph_for_each_link(priv, li, func_noml, func_dpcm);
                if (ret < 0)
                        break;
        }

        return ret;
}

static int graph_get_dais_count(struct asoc_simple_priv *priv,
                                struct link_info *li);

int audio_graph_parse_of(struct asoc_simple_priv *priv, struct device *dev)
{
        struct snd_soc_card *card = simple_priv_to_card(priv);
        struct link_info *li;
        int ret;

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

        card->owner = THIS_MODULE;
        card->dev = dev;

        ret = graph_get_dais_count(priv, li);
        if (ret < 0)
                return ret;

        if (!li->link)
                return -EINVAL;

        ret = asoc_simple_init_priv(priv, li);
        if (ret < 0)
                return ret;

        priv->pa_gpio = devm_gpiod_get_optional(dev, "pa", GPIOD_OUT_LOW);
        if (IS_ERR(priv->pa_gpio)) {
                ret = PTR_ERR(priv->pa_gpio);
                dev_err(dev, "failed to get amplifier gpio: %d\n", ret);
                return ret;
        }

        ret = asoc_simple_parse_widgets(card, NULL);
        if (ret < 0)
                return ret;

        ret = asoc_simple_parse_routing(card, NULL);
        if (ret < 0)
                return ret;

        memset(li, 0, sizeof(*li));
        ret = graph_for_each_link(priv, li,
                                  graph_dai_link_of,
                                  graph_dai_link_of_dpcm);
        if (ret < 0)
                goto err;

        ret = asoc_simple_parse_card_name(card, NULL);
        if (ret < 0)
                goto err;

        snd_soc_card_set_drvdata(card, priv);

        asoc_simple_debug_info(priv);

        ret = devm_snd_soc_register_card(dev, card);
        if (ret < 0)
                goto err;

        devm_kfree(dev, li);
        return 0;

err:
        asoc_simple_clean_reference(card);

        if (ret != -EPROBE_DEFER)
                dev_err(dev, "parse error %d\n", ret);

        return ret;
}
EXPORT_SYMBOL_GPL(audio_graph_parse_of);

static int graph_count_noml(struct asoc_simple_priv *priv,
                            struct device_node *cpu_ep,
                            struct device_node *codec_ep,
                            struct link_info *li)
{
        struct device *dev = simple_priv_to_dev(priv);

        if (li->link >= SNDRV_MAX_LINKS) {
                dev_err(dev, "too many links\n");
                return -EINVAL;
        }

        li->num[li->link].cpus          = 1;
        li->num[li->link].codecs        = 1;
        li->num[li->link].platforms     = 1;

        li->link += 1; /* 1xCPU-Codec */

        dev_dbg(dev, "Count As Normal\n");

        return 0;
}

static int graph_count_dpcm(struct asoc_simple_priv *priv,
                            struct device_node *cpu_ep,
                            struct device_node *codec_ep,
                            struct link_info *li)
{
        struct device *dev = simple_priv_to_dev(priv);

        if (li->link >= SNDRV_MAX_LINKS) {
                dev_err(dev, "too many links\n");
                return -EINVAL;
        }

        if (li->cpu) {
                li->num[li->link].cpus          = 1;
                li->num[li->link].platforms     = 1;

                li->link++; /* 1xCPU-dummy */
        } else {
                li->num[li->link].codecs        = 1;

                li->link++; /* 1xdummy-Codec */
        }

        dev_dbg(dev, "Count As DPCM\n");

        return 0;
}

static int graph_get_dais_count(struct asoc_simple_priv *priv,
                                struct link_info *li)
{
        /*
         * link_num :   number of links.
         *              CPU-Codec / CPU-dummy / dummy-Codec
         * dais_num :   number of DAIs
         * ccnf_num :   number of codec_conf
         *              same number for "dummy-Codec"
         *
         * ex1)
         * CPU0 --- Codec0      link : 5
         * CPU1 --- Codec1      dais : 7
         * CPU2 -/              ccnf : 1
         * CPU3 --- Codec2
         *
         *      => 5 links = 2xCPU-Codec + 2xCPU-dummy + 1xdummy-Codec
         *      => 7 DAIs  = 4xCPU + 3xCodec
         *      => 1 ccnf  = 1xdummy-Codec
         *
         * ex2)
         * CPU0 --- Codec0      link : 5
         * CPU1 --- Codec1      dais : 6
         * CPU2 -/              ccnf : 1
         * CPU3 -/
         *
         *      => 5 links = 1xCPU-Codec + 3xCPU-dummy + 1xdummy-Codec
         *      => 6 DAIs  = 4xCPU + 2xCodec
         *      => 1 ccnf  = 1xdummy-Codec
         *
         * ex3)
         * CPU0 --- Codec0      link : 6
         * CPU1 -/              dais : 6
         * CPU2 --- Codec1      ccnf : 2
         * CPU3 -/
         *
         *      => 6 links = 0xCPU-Codec + 4xCPU-dummy + 2xdummy-Codec
         *      => 6 DAIs  = 4xCPU + 2xCodec
         *      => 2 ccnf  = 2xdummy-Codec
         *
         * ex4)
         * CPU0 --- Codec0 (convert-rate)       link : 3
         * CPU1 --- Codec1                      dais : 4
         *                                      ccnf : 1
         *
         *      => 3 links = 1xCPU-Codec + 1xCPU-dummy + 1xdummy-Codec
         *      => 4 DAIs  = 2xCPU + 2xCodec
         *      => 1 ccnf  = 1xdummy-Codec
         */
        return graph_for_each_link(priv, li,
                                   graph_count_noml,
                                   graph_count_dpcm);
}

static int graph_probe(struct platform_device *pdev)
{
        struct asoc_simple_priv *priv;
        struct device *dev = &pdev->dev;
        struct snd_soc_card *card;

        /* Allocate the private data and the DAI link array */
        priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
        if (!priv)
                return -ENOMEM;

        card = simple_priv_to_card(priv);
        card->dapm_widgets      = graph_dapm_widgets;
        card->num_dapm_widgets  = ARRAY_SIZE(graph_dapm_widgets);
        card->probe             = asoc_graph_card_probe;

        if (of_device_get_match_data(dev))
                priv->dpcm_selectable = 1;

        return audio_graph_parse_of(priv, dev);
}

static const struct of_device_id graph_of_match[] = {
        { .compatible = "audio-graph-card", },
        { .compatible = "audio-graph-scu-card",
          .data = (void *)DPCM_SELECTABLE },
        {},
};
MODULE_DEVICE_TABLE(of, graph_of_match);

static struct platform_driver graph_card = {
        .driver = {
                .name = "asoc-audio-graph-card",
                .pm = &snd_soc_pm_ops,
                .of_match_table = graph_of_match,
        },
        .probe = graph_probe,
        .remove = asoc_simple_remove,
};
module_platform_driver(graph_card);

MODULE_ALIAS("platform:asoc-audio-graph-card");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("ASoC Audio Graph Sound Card");
MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");