// SPDX-License-Identifier: GPL-2.0
//
// ASoC Audio Graph Card2 support
//
// Copyright (C) 2020 Renesas Electronics Corp.
// Copyright (C) 2020 Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
//
// based on ${LINUX}/sound/soc/generic/audio-graph-card.c
#include <linux/clk.h>
#include <linux/device.h>
#include <linux/gpio/consumer.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_graph.h>
#include <linux/platform_device.h>
#include <linux/string.h>
#include <sound/graph_card.h>

/************************************
        daifmt
 ************************************
        ports {
                format = "left_j";
                port@0 {
                        bitclock-master;
                        sample0: endpoint@0 {
                                frame-master;
                        };
                        sample1: endpoint@1 {
                                format = "i2s";
                        };
                };
                ...
        };

 You can set daifmt at ports/port/endpoint.
 It uses *latest* format, and *share* master settings.
 In above case,
        sample0: left_j, bitclock-master, frame-master
        sample1: i2s,    bitclock-master

 If there was no settings, *Codec* will be
 bitclock/frame provider as default.
 see
        graph_parse_daifmt().

 "format" property is no longer needed on DT if both CPU/Codec drivers are
 supporting snd_soc_dai_ops :: .auto_selectable_formats.
 see
        snd_soc_runtime_get_dai_fmt()

        sample driver
                linux/sound/soc/renesas/rcar/core.c
                linux/sound/soc/codecs/ak4613.c
                linux/sound/soc/codecs/pcm3168a.c
                linux/sound/soc/soc-utils.c
                linux/sound/soc/generic/test-component.c

 ************************************
        Normal Audio-Graph
 ************************************

 CPU <---> Codec

 sound {
        compatible = "audio-graph-card2";
        links = <&cpu>;
 };

 CPU {
        cpu: port {
                bitclock-master;
                frame-master;
                cpu_ep: endpoint { remote-endpoint = <&codec_ep>; }; };
 };

 Codec {
        port {  codec_ep: endpoint { remote-endpoint = <&cpu_ep>; }; };
 };

 ************************************
        Multi-CPU/Codec
 ************************************

It has link connection part (= X,x) and list part (= A,B,a,b).
"links" is connection part of CPU side (= @).

        +----+          +---+
 CPU1 --|A  X| <-@----> |x a|-- Codec1
 CPU2 --|B   |          |  b|-- Codec2
        +----+          +---+

 sound {
        compatible = "audio-graph-card2";

(@)     links = <&mcpu>;

        multi {
                ports@0 {
(@)             mcpu:   port@0 { mcpu0_ep: endpoint { remote-endpoint = <&mcodec0_ep>;  }; };   // (X) to pair
                        port@1 { mcpu1_ep: endpoint { remote-endpoint = <&cpu1_ep>;     }; };   // (A) Multi Element
                        port@2 { mcpu2_ep: endpoint { remote-endpoint = <&cpu2_ep>;     }; };   // (B) Multi Element
                };
                ports@1 {
                        port@0 { mcodec0_ep: endpoint { remote-endpoint = <&mcpu0_ep>;  }; };   // (x) to pair
                        port@1 { mcodec1_ep: endpoint { remote-endpoint = <&codec1_ep>; }; };   // (a) Multi Element
                        port@2 { mcodec2_ep: endpoint { remote-endpoint = <&codec2_ep>; }; };   // (b) Multi Element
                };
        };
 };

 CPU {
        ports {
                bitclock-master;
                frame-master;
                port@0 { cpu1_ep: endpoint { remote-endpoint = <&mcpu1_ep>; }; };
                port@1 { cpu2_ep: endpoint { remote-endpoint = <&mcpu2_ep>; }; };
        };
 };

 Codec {
        ports {
                port@0 { codec1_ep: endpoint { remote-endpoint = <&mcodec1_ep>; }; };
                port@1 { codec2_ep: endpoint { remote-endpoint = <&mcodec2_ep>; }; };
        };
 };

 ************************************
        DPCM
 ************************************

                DSP
           ************
 PCM0 <--> * fe0  be0 * <--> DAI0: Codec Headset
 PCM1 <--> * fe1  be1 * <--> DAI1: Codec Speakers
 PCM2 <--> * fe2  be2 * <--> DAI2: MODEM
 PCM3 <--> * fe3  be3 * <--> DAI3: BT
           *      be4 * <--> DAI4: DMIC
           *      be5 * <--> DAI5: FM
           ************

 sound {
        compatible = "audio-graph-card2";

        // indicate routing
        routing = "xxx Playback", "xxx Playback",
                  "xxx Playback", "xxx Playback",
                  "xxx Playback", "xxx Playback";

        // indicate all Front-End, Back-End
        links = <&fe0, &fe1, ...,
                 &be0, &be1, ...>;

        dpcm {
                // Front-End
                ports@0 {
                        fe0: port@0 { fe0_ep: endpoint { remote-endpoint = <&pcm0_ep>; }; };
                        fe1: port@1 { fe1_ep: endpoint { remote-endpoint = <&pcm1_ep>; }; };
                        ...
                };
                // Back-End
                ports@1 {
                        be0: port@0 { be0_ep: endpoint { remote-endpoint = <&dai0_ep>; }; };
                        be1: port@1 { be1_ep: endpoint { remote-endpoint = <&dai1_ep>; }; };
                        ...
                };
        };
 };

 CPU {
        ports {
                bitclock-master;
                frame-master;
                port@0 { pcm0_ep: endpoint { remote-endpoint = <&fe0_ep>; }; };
                port@1 { pcm1_ep: endpoint { remote-endpoint = <&fe1_ep>; }; };
                ...
        };
 };

 Codec {
        ports {
                port@0 { dai0_ep: endpoint { remote-endpoint = <&be0_ep>; }; };
                port@1 { dai1_ep: endpoint { remote-endpoint = <&be1_ep>; }; };
                ...
        };
 };

 ************************************
        Codec to Codec
 ************************************

 +--+
 |  |<-- Codec0 <- IN
 |  |--> Codec1 -> OUT
 +--+

 sound {
        compatible = "audio-graph-card2";

        routing = "OUT" ,"DAI1 Playback",
                  "DAI0 Capture", "IN";

        links = <&c2c>;

        codec2codec {
                ports {
                        rate = <48000>;
                c2c:    port@0 { c2cf_ep: endpoint { remote-endpoint = <&codec0_ep>; }; };
                        port@1 { c2cb_ep: endpoint { remote-endpoint = <&codec1_ep>; }; };
        };
 };

 Codec {
        ports {
                port@0 {
                        bitclock-master;
                        frame-master;
                         codec0_ep: endpoint { remote-endpoint = <&c2cf_ep>; }; };
                port@1 { codec1_ep: endpoint { remote-endpoint = <&c2cb_ep>; }; };
        };
 };

*/

enum graph_type {
        GRAPH_NORMAL,
        GRAPH_DPCM,
        GRAPH_C2C,

        GRAPH_MULTI,    /* don't use ! Use this only in __graph_get_type() */
};

#define GRAPH_NODENAME_MULTI    "multi"
#define GRAPH_NODENAME_DPCM     "dpcm"
#define GRAPH_NODENAME_C2C      "codec2codec"

#define graph_ret(priv, ret) _graph_ret(priv, __func__, ret)
static inline int _graph_ret(struct simple_util_priv *priv,
                               const char *func, int ret)
{
        return snd_soc_ret(simple_priv_to_dev(priv), ret, "at %s()\n", func);
}

#define ep_to_port(ep)  of_get_parent(ep)
static struct device_node *port_to_ports(struct device_node *port)
{
        struct device_node *ports = of_get_parent(port);

        if (!of_node_name_eq(ports, "ports")) {
                of_node_put(ports);
                return NULL;
        }
        return ports;
}

static enum graph_type __graph_get_type(struct device_node *lnk)
{
        struct device_node *np, *parent_np;
        enum graph_type ret;

        /*
         * target {
         *      ports {
         * =>           lnk:    port@0 { ... };
         *                      port@1 { ... };
         *      };
         * };
         */
        np = of_get_parent(lnk);
        if (of_node_name_eq(np, "ports")) {
                parent_np = of_get_parent(np);
                of_node_put(np);
                np = parent_np;
        }

        if (of_node_name_eq(np, GRAPH_NODENAME_MULTI)) {
                ret = GRAPH_MULTI;
                fw_devlink_purge_absent_suppliers(&np->fwnode);
                goto out_put;
        }

        if (of_node_name_eq(np, GRAPH_NODENAME_DPCM)) {
                ret = GRAPH_DPCM;
                fw_devlink_purge_absent_suppliers(&np->fwnode);
                goto out_put;
        }

        if (of_node_name_eq(np, GRAPH_NODENAME_C2C)) {
                ret = GRAPH_C2C;
                fw_devlink_purge_absent_suppliers(&np->fwnode);
                goto out_put;
        }

        ret = GRAPH_NORMAL;

out_put:
        of_node_put(np);
        return ret;

}

static enum graph_type graph_get_type(struct simple_util_priv *priv,
                                      struct device_node *lnk)
{
        enum graph_type type = __graph_get_type(lnk);

        /* GRAPH_MULTI here means GRAPH_NORMAL */
        if (type == GRAPH_MULTI)
                type = GRAPH_NORMAL;

#ifdef DEBUG
        {
                struct device *dev = simple_priv_to_dev(priv);
                const char *str = "Normal";

                switch (type) {
                case GRAPH_DPCM:
                        if (graph_util_is_ports0(lnk))
                                str = "DPCM Front-End";
                        else
                                str = "DPCM Back-End";
                        break;
                case GRAPH_C2C:
                        str = "Codec2Codec";
                        break;
                default:
                        break;
                }

                dev_dbg(dev, "%pOF (%s)", lnk, str);
        }
#endif
        return type;
}

static int graph_lnk_is_multi(struct device_node *lnk)
{
        return __graph_get_type(lnk) == GRAPH_MULTI;
}

static struct device_node *graph_get_next_multi_ep(struct device_node **port, int idx)
{
        struct device_node *ports __free(device_node) = port_to_ports(*port);
        struct device_node *rep = NULL;

        /*
         * multi {
         *      ports {
         * =>   lnk:    port@0 { ...               }; // to pair
         *              port@1 { ep { ... = rep0 } }; // Multi Element
         *              port@2 { ep { ... = rep1 } }; // Multi Element
         *              ...
         *      };
         * };
         *
         * xxx {
         *      port@0 { rep0 };
         *      port@1 { rep1 };
         * };
         */

        /*
         * Don't use of_graph_get_next_port() here
         *
         * In overlay case, "port" are not necessarily in order. So we need to use
         * of_graph_get_port_by_id() instead
         */
        of_node_put(*port);

        *port = of_graph_get_port_by_id(ports, idx);
        if (*port) {
                struct device_node *ep __free(device_node) = of_graph_get_next_port_endpoint(*port, NULL);

                rep = of_graph_get_remote_endpoint(ep);
        }

        return rep;
}

static const struct snd_soc_ops graph_ops = {
        .startup        = simple_util_startup,
        .shutdown       = simple_util_shutdown,
        .hw_params      = simple_util_hw_params,
};

static void graph_parse_convert(struct device_node *ep,
                                struct simple_dai_props *props)
{
        struct device_node *port  __free(device_node) = ep_to_port(ep);
        struct device_node *ports __free(device_node) = port_to_ports(port);
        struct simple_util_data *adata = &props->adata;

        simple_util_parse_convert(ports, NULL, adata);
        simple_util_parse_convert(port, NULL, adata);
        simple_util_parse_convert(ep,   NULL, adata);
}

static int __graph_parse_node(struct simple_util_priv *priv,
                              enum graph_type gtype,
                              struct device_node *ep,
                              struct link_info *li,
                              int is_cpu, int idx)
{
        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 snd_soc_dai_link_component *dlc;
        struct simple_util_dai *dai;
        int ret, is_single_links = 0;

        if (is_cpu) {
                dlc = snd_soc_link_to_cpu(dai_link, idx);
                dai = simple_props_to_dai_cpu(dai_props, idx);
        } else {
                dlc = snd_soc_link_to_codec(dai_link, idx);
                dai = simple_props_to_dai_codec(dai_props, idx);
        }

        ret = graph_util_parse_dai(priv, ep, dlc, &is_single_links);
        if (ret < 0)
                goto end;

        ret = simple_util_parse_tdm(ep, dai);
        if (ret < 0)
                goto end;

        ret = simple_util_parse_tdm_width_map(priv, ep, dai);
        if (ret < 0)
                goto end;

        ret = simple_util_parse_clk(dev, ep, dai, dlc);
        if (ret < 0)
                goto end;

        /*
         * set DAI Name
         */
        if (!dai_link->name) {
                struct snd_soc_dai_link_component *cpus = dlc;
                struct snd_soc_dai_link_component *codecs = snd_soc_link_to_codec(dai_link, idx);
                char *cpu_multi   = "";
                char *codec_multi = "";

                if (dai_link->num_cpus > 1)
                        cpu_multi = "_multi";
                if (dai_link->num_codecs > 1)
                        codec_multi = "_multi";

                switch (gtype) {
                case GRAPH_NORMAL:
                        /* run is_cpu only. see audio_graph2_link_normal() */
                        if (is_cpu)
                                simple_util_set_dailink_name(priv, dai_link, "%s%s-%s%s",
                                                               cpus->dai_name,   cpu_multi,
                                                             codecs->dai_name, codec_multi);
                        break;
                case GRAPH_DPCM:
                        if (is_cpu)
                                simple_util_set_dailink_name(priv, dai_link, "fe.%pOFP.%s%s",
                                                cpus->of_node, cpus->dai_name, cpu_multi);
                        else
                                simple_util_set_dailink_name(priv, dai_link, "be.%pOFP.%s%s",
                                                codecs->of_node, codecs->dai_name, codec_multi);
                        break;
                case GRAPH_C2C:
                        /* run is_cpu only. see audio_graph2_link_c2c() */
                        if (is_cpu)
                                simple_util_set_dailink_name(priv, dai_link, "c2c.%s%s-%s%s",
                                                             cpus->dai_name,   cpu_multi,
                                                             codecs->dai_name, codec_multi);
                        break;
                default:
                        break;
                }
        }

        /*
         * Check "prefix" from top node
         * if DPCM-BE case
         */
        if (!is_cpu && gtype == GRAPH_DPCM) {
                struct snd_soc_dai_link_component *codecs = snd_soc_link_to_codec(dai_link, idx);
                struct snd_soc_codec_conf *cconf = simple_props_to_codec_conf(dai_props, idx);
                struct device_node *rport  __free(device_node) = ep_to_port(ep);
                struct device_node *rports __free(device_node) = port_to_ports(rport);

                snd_soc_of_parse_node_prefix(rports, cconf, codecs->of_node, "prefix");
                snd_soc_of_parse_node_prefix(rport,  cconf, codecs->of_node, "prefix");
        }

        if (is_cpu) {
                struct snd_soc_dai_link_component *cpus = dlc;
                struct snd_soc_dai_link_component *platforms = snd_soc_link_to_platform(dai_link, idx);

                simple_util_canonicalize_cpu(cpus, is_single_links);
                simple_util_canonicalize_platform(platforms, cpus);
        }
end:
        return graph_ret(priv, ret);
}

static int graph_parse_node_multi_nm(struct simple_util_priv *priv,
                                     struct snd_soc_dai_link *dai_link,
                                     int *nm_idx, int cpu_idx,
                                     struct device_node *mcpu_port)
{
        /*
         *              +---+           +---+
         *              |  X|<-@------->|x  |
         *              |   |           |   |
         *      cpu0 <--|A 1|<--------->|4 a|-> codec0
         *      cpu1 <--|B 2|<-----+--->|5 b|-> codec1
         *      cpu2 <--|C 3|<----/     +---+
         *              +---+
         *
         * multi {
         *      ports {
         *              port@0 { mcpu_top_ep    {...  = mcodec_ep;      }; };   // (X) to pair
         * <mcpu_port>  port@1 { mcpu0_ep       { ... = cpu0_ep;        };      // (A) Multi Element
         *                       mcpu0_ep_0     { ... = mcodec0_ep_0;   }; };   // (1) connected Codec
         *              port@2 { mcpu1_ep       { ... = cpu1_ep;        };      // (B) Multi Element
         *                       mcpu1_ep_0     { ... = mcodec1_ep_0;   }; };   // (2) connected Codec
         *              port@3 { mcpu2_ep       { ... = cpu2_ep;        };      // (C) Multi Element
         *                       mcpu2_ep_0     { ... = mcodec1_ep_1;   }; };   // (3) connected Codec
         *      };
         *
         *      ports {
         *              port@0 { mcodec_top_ep  {...  = mcpu_ep;        }; };   // (x) to pair
         * <mcodec_port>port@1 { mcodec0_ep     { ... = codec0_ep;      };      // (a) Multi Element
         *                       mcodec0_ep_0   { ... = mcpu0_ep_0;     }; };   // (4) connected CPU
         *              port@2 { mcodec1_ep     { ... = codec1_ep;      };      // (b) Multi Element
         *                       mcodec1_ep_0   { ... = mcpu1_ep_0;     };      // (5) connected CPU
         *                       mcodec1_ep_1   { ... = mcpu2_ep_0;     }; };   // (5) connected CPU
         *      };
         * };
         */
        struct device_node *mcpu_ep             __free(device_node) = of_graph_get_next_port_endpoint(mcpu_port, NULL);
        struct device_node *mcpu_ports          __free(device_node) = port_to_ports(mcpu_port);
        struct device_node *mcpu_port_top       __free(device_node) = of_graph_get_next_port(mcpu_ports, NULL);
        struct device_node *mcpu_ep_top         __free(device_node) = of_graph_get_next_port_endpoint(mcpu_port_top, NULL);
        struct device_node *mcodec_ep_top       __free(device_node) = of_graph_get_remote_endpoint(mcpu_ep_top);
        struct device_node *mcodec_port_top     __free(device_node) = ep_to_port(mcodec_ep_top);
        struct device_node *mcodec_ports        __free(device_node) = port_to_ports(mcodec_port_top);
        int nm_max = max(dai_link->num_cpus, dai_link->num_codecs);
        int ret = -EINVAL;

        if (cpu_idx > dai_link->num_cpus)
                goto end;

        for_each_of_graph_port_endpoint(mcpu_port, mcpu_ep_n) {
                int codec_idx = 0;

                /* ignore 1st ep which is for element */
                if (mcpu_ep_n == mcpu_ep)
                        continue;

                if (*nm_idx > nm_max)
                        break;

                struct device_node *mcodec_ep_n __free(device_node) = of_graph_get_remote_endpoint(mcpu_ep_n);
                struct device_node *mcodec_port __free(device_node) = ep_to_port(mcodec_ep_n);

                ret = -EINVAL;
                if (mcodec_ports != port_to_ports(mcodec_port))
                        break;

                for_each_of_graph_port(mcodec_ports, mcodec_port_i) {

                        /* ignore 1st port which is for pair connection */
                        if (mcodec_port_top == mcodec_port_i)
                                continue;

                        if (codec_idx > dai_link->num_codecs)
                                break;

                        if (mcodec_port_i == mcodec_port) {
                                dai_link->ch_maps[*nm_idx].cpu   = cpu_idx;
                                dai_link->ch_maps[*nm_idx].codec = codec_idx;

                                (*nm_idx)++;
                                ret = 0;
                                break;
                        }
                        codec_idx++;
                }
                if (ret < 0)
                        break;
        }
end:
        return graph_ret(priv, ret);
}

static int graph_parse_node_multi(struct simple_util_priv *priv,
                                  enum graph_type gtype,
                                  struct device_node *port,
                                  struct link_info *li, int is_cpu)
{
        struct snd_soc_dai_link *dai_link = simple_priv_to_link(priv, li->link);
        struct device *dev = simple_priv_to_dev(priv);
        int ret = -ENOMEM;
        int nm_idx = 0;
        int nm_max = max(dai_link->num_cpus, dai_link->num_codecs);

        /*
         * create ch_maps if CPU:Codec = N:M
         * DPCM is out of scope
         */
        if (gtype != GRAPH_DPCM && !dai_link->ch_maps &&
            dai_link->num_cpus > 1 && dai_link->num_codecs > 1 &&
            dai_link->num_cpus != dai_link->num_codecs) {

                dai_link->ch_maps = devm_kcalloc(dev, nm_max,
                                        sizeof(struct snd_soc_dai_link_ch_map), GFP_KERNEL);
                if (!dai_link->ch_maps)
                        goto multi_err;
        }

        for (int idx = 0;; idx++) {
                /*
                 * multi {
                 *      ports {
                 * <port>       port@0 { ...                        }; // to pair
                 *              port@1 { mcpu1_ep { ... = cpu1_ep };}; // Multi Element
                 *              port@2 { mcpu2_ep { ... = cpu2_ep };}; // Multi Element
                 *      };
                 * };
                 *
                 * cpu {
                 *      ports {
                 * <ep>         port@0 { cpu1_ep   { ... = mcpu1_ep };};
                 *      };
                 * };
                 */
                struct device_node *ep __free(device_node) = graph_get_next_multi_ep(&port, idx + 1);
                if (!ep)
                        break;

                ret = __graph_parse_node(priv, gtype, ep, li, is_cpu, idx);
                if (ret < 0)
                        goto multi_err;

                /* CPU:Codec = N:M */
                if (is_cpu && dai_link->ch_maps) {
                        ret = graph_parse_node_multi_nm(priv, dai_link, &nm_idx, idx, port);
                        if (ret < 0)
                                goto multi_err;
                }
        }

        if (is_cpu && dai_link->ch_maps && (nm_idx != nm_max))
                ret = -EINVAL;

multi_err:
        return graph_ret(priv, ret);
}

static int graph_parse_node_single(struct simple_util_priv *priv,
                                   enum graph_type gtype,
                                   struct device_node *ep,
                                   struct link_info *li, int is_cpu)
{
        return graph_ret(priv, __graph_parse_node(priv, gtype, ep, li, is_cpu, 0));
}

static int graph_parse_node(struct simple_util_priv *priv,
                            enum graph_type gtype,
                            struct device_node *ep,
                            struct link_info *li, int is_cpu)
{
        struct device_node *port __free(device_node) = ep_to_port(ep);
        int ret;

        if (graph_lnk_is_multi(port))
                ret = graph_parse_node_multi(priv, gtype, port, li, is_cpu);
        else
                ret = graph_parse_node_single(priv, gtype, ep, li, is_cpu);

        return graph_ret(priv, ret);
}

static void graph_parse_daifmt(struct device_node *node, unsigned int *daifmt)
{
        unsigned int fmt;

        if (!node)
                return;

        /*
         * see also above "daifmt" explanation
         * and samples.
         */

        /*
         *      ports {
         * (A)
         *              port {
         * (B)
         *                      endpoint {
         * (C)
         *                      };
         *              };
         *      };
         * };
         */

#define update_daifmt(name)                                     \
        if (!(*daifmt & SND_SOC_DAIFMT_##name##_MASK) &&        \
                 (fmt & SND_SOC_DAIFMT_##name##_MASK))          \
                *daifmt |= fmt & SND_SOC_DAIFMT_##name##_MASK

        /*
         * format
         *
         * This function is called by (C) -> (B) -> (A) order.
         * Set if applicable part was not yet set.
         */
        fmt = snd_soc_daifmt_parse_format(node, NULL);
        update_daifmt(FORMAT);
        update_daifmt(CLOCK);
        update_daifmt(INV);
}

static unsigned int graph_parse_bitframe(struct device_node *ep)
{
        struct device_node *port  __free(device_node) = ep_to_port(ep);
        struct device_node *ports __free(device_node) = port_to_ports(port);

        return  snd_soc_daifmt_clock_provider_from_bitmap(
                        snd_soc_daifmt_parse_clock_provider_as_bitmap(ep,    NULL) |
                        snd_soc_daifmt_parse_clock_provider_as_bitmap(port,  NULL) |
                        snd_soc_daifmt_parse_clock_provider_as_bitmap(ports, NULL));
}

static void graph_link_init(struct simple_util_priv *priv,
                            struct device_node *lnk,
                            struct device_node *ep_cpu,
                            struct device_node *ep_codec,
                            struct link_info *li,
                            int is_cpu_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 device_node *port_cpu = ep_to_port(ep_cpu);
        struct device_node *port_codec = ep_to_port(ep_codec);
        struct device_node *multi_cpu_port = NULL, *multi_codec_port = NULL;
        struct snd_soc_dai_link_component *dlc;
        unsigned int daifmt = 0;
        bool playback_only = 0, capture_only = 0;
        enum snd_soc_trigger_order trigger_start = SND_SOC_TRIGGER_ORDER_DEFAULT;
        enum snd_soc_trigger_order trigger_stop  = SND_SOC_TRIGGER_ORDER_DEFAULT;
        int multi_cpu_port_idx = 1, multi_codec_port_idx = 1;
        int i;

        if (graph_lnk_is_multi(port_cpu)) {
                multi_cpu_port = port_cpu;
                ep_cpu = graph_get_next_multi_ep(&multi_cpu_port, multi_cpu_port_idx++);
                of_node_put(port_cpu);
                port_cpu = ep_to_port(ep_cpu);
        } else {
                of_node_get(ep_cpu);
        }
        struct device_node *ports_cpu __free(device_node) = port_to_ports(port_cpu);

        if (graph_lnk_is_multi(port_codec)) {
                multi_codec_port = port_codec;
                ep_codec = graph_get_next_multi_ep(&multi_codec_port, multi_codec_port_idx++);
                of_node_put(port_codec);
                port_codec = ep_to_port(ep_codec);
        } else {
                of_node_get(ep_codec);
        }
        struct device_node *ports_codec __free(device_node) = port_to_ports(port_codec);

        graph_parse_daifmt(ep_cpu,      &daifmt);
        graph_parse_daifmt(ep_codec,    &daifmt);
        graph_parse_daifmt(port_cpu,    &daifmt);
        graph_parse_daifmt(port_codec,  &daifmt);
        graph_parse_daifmt(ports_cpu,   &daifmt);
        graph_parse_daifmt(ports_codec, &daifmt);
        graph_parse_daifmt(lnk,         &daifmt);

        graph_util_parse_link_direction(lnk,            &playback_only, &capture_only);
        graph_util_parse_link_direction(ports_cpu,      &playback_only, &capture_only);
        graph_util_parse_link_direction(ports_codec,    &playback_only, &capture_only);
        graph_util_parse_link_direction(port_cpu,       &playback_only, &capture_only);
        graph_util_parse_link_direction(port_codec,     &playback_only, &capture_only);
        graph_util_parse_link_direction(ep_cpu,         &playback_only, &capture_only);
        graph_util_parse_link_direction(ep_codec,       &playback_only, &capture_only);

        of_property_read_u32(lnk,               "mclk-fs", &dai_props->mclk_fs);
        of_property_read_u32(ports_cpu,         "mclk-fs", &dai_props->mclk_fs);
        of_property_read_u32(ports_codec,       "mclk-fs", &dai_props->mclk_fs);
        of_property_read_u32(port_cpu,          "mclk-fs", &dai_props->mclk_fs);
        of_property_read_u32(port_codec,        "mclk-fs", &dai_props->mclk_fs);
        of_property_read_u32(ep_cpu,            "mclk-fs", &dai_props->mclk_fs);
        of_property_read_u32(ep_codec,          "mclk-fs", &dai_props->mclk_fs);

        graph_util_parse_trigger_order(priv, lnk,               &trigger_start, &trigger_stop);
        graph_util_parse_trigger_order(priv, ports_cpu,         &trigger_start, &trigger_stop);
        graph_util_parse_trigger_order(priv, ports_codec,       &trigger_start, &trigger_stop);
        graph_util_parse_trigger_order(priv, port_cpu,          &trigger_start, &trigger_stop);
        graph_util_parse_trigger_order(priv, port_cpu,          &trigger_start, &trigger_stop);
        graph_util_parse_trigger_order(priv, ep_cpu,            &trigger_start, &trigger_stop);
        graph_util_parse_trigger_order(priv, ep_codec,          &trigger_start, &trigger_stop);

        for_each_link_cpus(dai_link, i, dlc) {
                dlc->ext_fmt = graph_parse_bitframe(ep_cpu);

                if (multi_cpu_port)
                        ep_cpu = graph_get_next_multi_ep(&multi_cpu_port, multi_cpu_port_idx++);
        }

        for_each_link_codecs(dai_link, i, dlc) {
                dlc->ext_fmt = graph_parse_bitframe(ep_codec);

                if (multi_codec_port)
                        ep_codec = graph_get_next_multi_ep(&multi_codec_port, multi_codec_port_idx++);
        }

        /*** Don't use port_cpu / port_codec after here ***/

        dai_link->playback_only = playback_only;
        dai_link->capture_only  = capture_only;

        dai_link->trigger_start = trigger_start;
        dai_link->trigger_stop  = trigger_stop;

        dai_link->dai_fmt       = daifmt;
        dai_link->init          = simple_util_dai_init;
        dai_link->ops           = &graph_ops;
        if (priv->ops)
                dai_link->ops   = priv->ops;

        of_node_put(port_cpu);
        of_node_put(port_codec);
        of_node_put(ep_cpu);
        of_node_put(ep_codec);
}

int audio_graph2_link_normal(struct simple_util_priv *priv,
                             struct device_node *lnk,
                             struct link_info *li)
{
        struct device_node *cpu_port = lnk;
        struct device_node *cpu_ep      __free(device_node) = of_graph_get_next_port_endpoint(cpu_port, NULL);
        struct device_node *codec_ep    __free(device_node) = of_graph_get_remote_endpoint(cpu_ep);
        int ret;

        /*
         * call Codec first.
         * see
         *      __graph_parse_node() :: DAI Naming
         */
        ret = graph_parse_node(priv, GRAPH_NORMAL, codec_ep, li, 0);
        if (ret < 0)
                goto end;

        /*
         * call CPU, and set DAI Name
         */
        ret = graph_parse_node(priv, GRAPH_NORMAL, cpu_ep, li, 1);
        if (ret < 0)
                goto end;

        graph_link_init(priv, lnk, cpu_ep, codec_ep, li, 1);

end:
        return graph_ret(priv, ret);
}
EXPORT_SYMBOL_GPL(audio_graph2_link_normal);

int audio_graph2_link_dpcm(struct simple_util_priv *priv,
                           struct device_node *lnk,
                           struct link_info *li)
{
        struct device_node *ep  __free(device_node) = of_graph_get_next_port_endpoint(lnk, NULL);
        struct device_node *rep __free(device_node) = of_graph_get_remote_endpoint(ep);
        struct device_node *cpu_ep = NULL;
        struct device_node *codec_ep = NULL;
        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);
        int is_cpu = graph_util_is_ports0(lnk);
        int ret;

        if (is_cpu) {
                cpu_ep = rep;

                /*
                 * dpcm {
                 *      // Front-End
                 *      ports@0 {
                 * =>           lnk: port@0 { ep: { ... = rep }; };
                 *               ...
                 *      };
                 *      // Back-End
                 *      ports@0 {
                 *               ...
                 *      };
                 * };
                 *
                 * CPU {
                 *      rports: ports {
                 *              rport: port@0 { rep: { ... = ep } };
                 *      }
                 * }
                 */
                /*
                 * setup CPU here, Codec is already set as dummy.
                 * see
                 *      simple_util_init_priv()
                 */
                dai_link->dynamic               = 1;
                dai_link->dpcm_merged_format    = 1;

                ret = graph_parse_node(priv, GRAPH_DPCM, cpu_ep, li, 1);
                if (ret)
                        return ret;

        } else {
                codec_ep = rep;

                /*
                 * dpcm {
                 *      // Front-End
                 *      ports@0 {
                 *               ...
                 *      };
                 *      // Back-End
                 *      ports@0 {
                 * =>           lnk: port@0 { ep: { ... = rep; }; };
                 *               ...
                 *      };
                 * };
                 *
                 * Codec {
                 *      rports: ports {
                 *              rport: port@0 { rep: { ... = ep; }; };
                 *      }
                 * }
                 */
                /*
                 * setup Codec here, CPU is already set as dummy.
                 * see
                 *      simple_util_init_priv()
                 */

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

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

        graph_parse_convert(ep,  dai_props); /* at node of <dpcm> */
        graph_parse_convert(rep, dai_props); /* at node of <CPU/Codec> */

        graph_link_init(priv, lnk, cpu_ep, codec_ep, li, is_cpu);

        return graph_ret(priv, ret);
}
EXPORT_SYMBOL_GPL(audio_graph2_link_dpcm);

int audio_graph2_link_c2c(struct simple_util_priv *priv,
                          struct device_node *lnk,
                          struct link_info *li)
{
        struct snd_soc_dai_link *dai_link = simple_priv_to_link(priv, li->link);
        struct device_node *port0 = lnk;
        struct device_node *ports __free(device_node) = port_to_ports(port0);
        struct device_node *port1 __free(device_node) = of_graph_get_next_port(ports, port0);
        u32 val = 0;
        int ret = -EINVAL;

        /*
         * codec2codec {
         *      ports {
         *              rate = <48000>;
         * =>   lnk:    port@0 { c2c0_ep: { ... = codec0_ep; }; };
         *              port@1 { c2c1_ep: { ... = codec1_ep; }; };
         *      };
         * };
         *
         * Codec {
         *      ports {
         *              port@0 { codec0_ep: ... }; };
         *              port@1 { codec1_ep: ... }; };
         *      };
         * };
         */

        /*
         * Card2 can use original Codec2Codec settings if DT has.
         * It will use default settings if no settings on DT.
         * see
         *      simple_util_init_for_codec2codec()
         *
         * Add more settings here if needed
         */
        of_property_read_u32(ports, "rate", &val);
        if (val) {
                struct device *dev = simple_priv_to_dev(priv);
                struct snd_soc_pcm_stream *c2c_conf;

                c2c_conf = devm_kzalloc(dev, sizeof(*c2c_conf), GFP_KERNEL);
                if (!c2c_conf) {
                        /*
                         * Clang doesn't allow to use "goto end" before calling __free(),
                         * because it bypasses the initialization. Use graph_ret() directly.
                         */
                        return graph_ret(priv, -ENOMEM);
                }

                c2c_conf->formats       = SNDRV_PCM_FMTBIT_S32_LE; /* update ME */
                c2c_conf->rates         = SNDRV_PCM_RATE_8000_384000;
                c2c_conf->rate_min      =
                c2c_conf->rate_max      = val;
                c2c_conf->channels_min  =
                c2c_conf->channels_max  = 2; /* update ME */

                dai_link->c2c_params            = c2c_conf;
                dai_link->num_c2c_params        = 1;
        }

        struct device_node *ep0 __free(device_node) = of_graph_get_next_port_endpoint(port0, NULL);
        struct device_node *ep1 __free(device_node) = of_graph_get_next_port_endpoint(port1, NULL);

        struct device_node *codec0_ep __free(device_node) = of_graph_get_remote_endpoint(ep0);
        struct device_node *codec1_ep __free(device_node) = of_graph_get_remote_endpoint(ep1);

        /*
         * call Codec first.
         * see
         *      __graph_parse_node() :: DAI Naming
         */
        ret = graph_parse_node(priv, GRAPH_C2C, codec1_ep, li, 0);
        if (ret < 0)
                goto end;

        /*
         * call CPU, and set DAI Name
         */
        ret = graph_parse_node(priv, GRAPH_C2C, codec0_ep, li, 1);
        if (ret < 0)
                goto end;

        graph_link_init(priv, lnk, codec0_ep, codec1_ep, li, 1);
end:
        return graph_ret(priv, ret);
}
EXPORT_SYMBOL_GPL(audio_graph2_link_c2c);

static int graph_link(struct simple_util_priv *priv,
                      struct graph2_custom_hooks *hooks,
                      enum graph_type gtype,
                      struct device_node *lnk,
                      struct link_info *li)
{
        struct device *dev = simple_priv_to_dev(priv);
        GRAPH2_CUSTOM func = NULL;
        int ret = -EINVAL;

        switch (gtype) {
        case GRAPH_NORMAL:
                if (hooks && hooks->custom_normal)
                        func = hooks->custom_normal;
                else
                        func = audio_graph2_link_normal;
                break;
        case GRAPH_DPCM:
                if (hooks && hooks->custom_dpcm)
                        func = hooks->custom_dpcm;
                else
                        func = audio_graph2_link_dpcm;
                break;
        case GRAPH_C2C:
                if (hooks && hooks->custom_c2c)
                        func = hooks->custom_c2c;
                else
                        func = audio_graph2_link_c2c;
                break;
        default:
                break;
        }

        if (!func) {
                dev_err(dev, "non supported gtype (%d)\n", gtype);
                goto err;
        }

        ret = func(priv, lnk, li);
        if (ret < 0)
                goto err;

        li->link++;
err:
        return graph_ret(priv, ret);
}

static int graph_counter(struct device_node *lnk)
{
        /*
         * Multi CPU / Codec
         *
         * multi {
         *      ports {
         * =>           lnk:    port@0 { ... }; // to pair
         *                      port@1 { ... }; // Multi Element
         *                      port@2 { ... }; // Multi Element
         *                      ...
         *      };
         * };
         *
         * ignore first lnk part
         */
        if (graph_lnk_is_multi(lnk)) {
                struct device_node *ports = port_to_ports(lnk);

                /*
                 * CPU/Codec = N:M case has many endpoints.
                 * We can't use of_graph_get_endpoint_count() here
                 */
                return of_graph_get_port_count(ports) - 1;
        }
        /*
         * Single CPU / Codec
         */
        else
                return 1;
}

static int graph_count_normal(struct simple_util_priv *priv,
                              struct device_node *lnk,
                              struct link_info *li)
{
        struct device_node *cpu_port = lnk;
        struct device_node *cpu_ep      __free(device_node) = of_graph_get_next_port_endpoint(cpu_port, NULL);
        struct device_node *codec_port  __free(device_node) = of_graph_get_remote_port(cpu_ep);

        /*
         *      CPU {
         * =>           lnk: port { endpoint { .. }; };
         *      };
         */
        /*
         * DON'T REMOVE platforms
         * see
         *      simple-card.c :: simple_count_noml()
         */
        li->num[li->link].cpus          =
        li->num[li->link].platforms     = graph_counter(cpu_port);

        li->num[li->link].codecs        = graph_counter(codec_port);

        return 0;
}

static int graph_count_dpcm(struct simple_util_priv *priv,
                            struct device_node *lnk,
                            struct link_info *li)
{
        struct device_node *ep          __free(device_node) = of_graph_get_next_port_endpoint(lnk, NULL);
        struct device_node *rport       __free(device_node) = of_graph_get_remote_port(ep);

        /*
         * dpcm {
         *      // Front-End
         *      ports@0 {
         * =>           lnk: port@0 { endpoint { ... }; };
         *               ...
         *      };
         *      // Back-End
         *      ports@1 {
         * =>           lnk: port@0 { endpoint { ... }; };
         *               ...
         *      };
         * };
         */

        if (graph_util_is_ports0(lnk)) {
                /*
                 * DON'T REMOVE platforms
                 * see
                 *      simple-card.c :: simple_count_noml()
                 */
                li->num[li->link].cpus          = graph_counter(rport); /* FE */
                li->num[li->link].platforms     = graph_counter(rport);
        } else {
                li->num[li->link].codecs        = graph_counter(rport); /* BE */
        }

        return 0;
}

static int graph_count_c2c(struct simple_util_priv *priv,
                           struct device_node *lnk,
                           struct link_info *li)
{
        struct device_node *ports       __free(device_node) = port_to_ports(lnk);
        struct device_node *port0       = of_node_get(lnk);
        struct device_node *port1       = of_node_get(of_graph_get_next_port(ports, of_node_get(port0)));
        struct device_node *ep0         __free(device_node) = of_graph_get_next_port_endpoint(port0, NULL);
        struct device_node *ep1         __free(device_node) = of_graph_get_next_port_endpoint(port1, NULL);
        struct device_node *codec0      __free(device_node) = of_graph_get_remote_port(ep0);
        struct device_node *codec1      __free(device_node) = of_graph_get_remote_port(ep1);

        /*
         * codec2codec {
         *      ports {
         * =>   lnk:    port@0 { endpoint { ... }; };
         *              port@1 { endpoint { ... }; };
         *      };
         * };
         */
        /*
         * DON'T REMOVE platforms
         * see
         *      simple-card.c :: simple_count_noml()
         */
        li->num[li->link].cpus          =
        li->num[li->link].platforms     = graph_counter(codec0);

        li->num[li->link].codecs        = graph_counter(codec1);

        return 0;
}

static int graph_count(struct simple_util_priv *priv,
                       struct graph2_custom_hooks *hooks,
                       enum graph_type gtype,
                       struct device_node *lnk,
                       struct link_info *li)
{
        struct device *dev = simple_priv_to_dev(priv);
        GRAPH2_CUSTOM func = NULL;
        int ret = -EINVAL;

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

        switch (gtype) {
        case GRAPH_NORMAL:
                func = graph_count_normal;
                break;
        case GRAPH_DPCM:
                func = graph_count_dpcm;
                break;
        case GRAPH_C2C:
                func = graph_count_c2c;
                break;
        default:
                break;
        }

        if (!func) {
                dev_err(dev, "non supported gtype (%d)\n", gtype);
                goto err;
        }

        ret = func(priv, lnk, li);
        if (ret < 0)
                goto err;

        li->link++;
err:
        return graph_ret(priv, ret);
}

static int graph_for_each_link(struct simple_util_priv *priv,
                               struct graph2_custom_hooks *hooks,
                               struct link_info *li,
                               int (*func)(struct simple_util_priv *priv,
                                           struct graph2_custom_hooks *hooks,
                                           enum graph_type gtype,
                                           struct device_node *lnk,
                                           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 *lnk;
        enum graph_type gtype;
        int rc, ret = 0;

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

                gtype = graph_get_type(priv, lnk);

                ret = func(priv, hooks, gtype, lnk, li);
                if (ret < 0)
                        break;
        }

        return graph_ret(priv, ret);
}

int audio_graph2_parse_of(struct simple_util_priv *priv, struct device *dev,
                          struct graph2_custom_hooks *hooks)
{
        struct snd_soc_card *card = simple_priv_to_card(priv);
        int ret;

        struct link_info *li __free(kfree) = kzalloc_obj(*li);
        if (!li)
                return -ENOMEM;

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

        if ((hooks) && (hooks)->hook_pre) {
                ret = (hooks)->hook_pre(priv);
                if (ret < 0)
                        goto err;
        }

        ret = graph_for_each_link(priv, hooks, li, graph_count);
        if (!li->link)
                ret = -EINVAL;
        if (ret < 0)
                goto err;

        ret = simple_util_init_priv(priv, li);
        if (ret < 0)
                goto err;

        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);
                goto err;
        }

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

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

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

        ret = simple_util_parse_card_name(priv, NULL);
        if (ret < 0)
                goto err;

        snd_soc_card_set_drvdata(card, priv);

        if ((hooks) && (hooks)->hook_post) {
                ret = (hooks)->hook_post(priv);
                if (ret < 0)
                        goto err;
        }

        simple_util_debug_info(priv);

        ret = snd_soc_of_parse_aux_devs(card, "aux-devs");
        if (ret < 0)
                goto err;

        ret = devm_snd_soc_register_card(dev, card);
err:
        if (ret < 0)
                dev_err_probe(dev, ret, "parse error\n");

        return graph_ret(priv, ret);
}
EXPORT_SYMBOL_GPL(audio_graph2_parse_of);

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

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

        return audio_graph2_parse_of(priv, dev, NULL);
}

static const struct of_device_id graph_of_match[] = {
        { .compatible = "audio-graph-card2", },
        {},
};
MODULE_DEVICE_TABLE(of, graph_of_match);

static struct platform_driver graph_card = {
        .driver = {
                .name = "asoc-audio-graph-card2",
                .pm = &snd_soc_pm_ops,
                .of_match_table = graph_of_match,
        },
        .probe  = graph_probe,
        .remove = simple_util_remove,
};
module_platform_driver(graph_card);

MODULE_ALIAS("platform:asoc-audio-graph-card2");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("ASoC Audio Graph Card2");
MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");