--- /dev/null
+// 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.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>
+
+/************************************
+       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().
+
+ ************************************
+       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>; }; };
+ };
+
+*/
+
+enum graph_type {
+       GRAPH_NORMAL,
+};
+
+#define port_to_endpoint(port) of_get_child_by_name(port, "endpoint")
+
+static enum graph_type graph_get_type(struct asoc_simple_priv *priv,
+                                     struct device_node *lnk)
+{
+       enum graph_type type = GRAPH_NORMAL;
+
+#ifdef DEBUG
+       {
+               struct device *dev = simple_priv_to_dev(priv);
+               const char *str = "Normal";
+
+               dev_dbg(dev, "%pOF (%s)", lnk, str);
+       }
+#endif
+       return type;
+}
+
+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 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_mclk_fs(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);
+
+       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,
+                             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 asoc_simple_dai *dai;
+       int ret, is_single_links = 0;
+
+       if (is_cpu) {
+               dlc = asoc_link_to_cpu(dai_link, idx);
+               dai = simple_props_to_dai_cpu(dai_props, idx);
+       } else {
+               dlc = asoc_link_to_codec(dai_link, idx);
+               dai = simple_props_to_dai_codec(dai_props, idx);
+       }
+
+       graph_parse_mclk_fs(ep, dai_props);
+
+       ret = asoc_simple_parse_dai(ep, dlc, &is_single_links);
+       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;
+
+       /*
+        * set DAI Name
+        */
+       if (!dai_link->name) {
+               struct snd_soc_dai_link_component *cpus = dlc;
+               struct snd_soc_dai_link_component *codecs = asoc_link_to_codec(dai_link, idx);
+
+               switch (gtype) {
+               case GRAPH_NORMAL:
+                       /* run is_cpu only. see audio_graph2_link_normal() */
+                       if (is_cpu)
+                               asoc_simple_set_dailink_name(dev, dai_link, "%s-%s",
+                                                            cpus->dai_name, codecs->dai_name);
+                       break;
+               default:
+                       break;
+               }
+       }
+
+       if (is_cpu) {
+               struct snd_soc_dai_link_component *cpus = dlc;
+               struct snd_soc_dai_link_component *platforms = asoc_link_to_platform(dai_link, idx);
+
+               asoc_simple_canonicalize_cpu(cpus, is_single_links);
+               asoc_simple_canonicalize_platform(platforms, cpus);
+       }
+
+       return 0;
+}
+
+static int graph_parse_node(struct asoc_simple_priv *priv,
+                           enum graph_type gtype,
+                           struct device_node *port,
+                           struct link_info *li, int is_cpu)
+{
+       struct device_node *ep = port_to_endpoint(port);
+
+       /* Need Multi support later */
+       return __graph_parse_node(priv, gtype, ep, li, is_cpu, 0);
+}
+
+static void graph_parse_daifmt(struct device_node *node,
+                              unsigned int *daifmt, unsigned int *bit_frame)
+{
+       unsigned int fmt;
+
+       /*
+        * see also above "daifmt" explanation
+        * and samples.
+        */
+
+       /*
+        *      ports {
+        * (A)
+        *              port {
+        * (B)
+        *                      endpoint {
+        * (C)
+        *                      };
+        *              };
+        *      };
+        * };
+        */
+
+       /*
+        * clock_provider:
+        *
+        * It can be judged it is provider
+        * if (A) or (B) or (C) has bitclock-master / frame-master flag.
+        *
+        * use "or"
+        */
+       *bit_frame |= snd_soc_daifmt_parse_clock_provider_as_bitmap(node, NULL);
+
+#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 void graph_link_init(struct asoc_simple_priv *priv,
+                           struct device_node *port,
+                           struct link_info *li,
+                           int is_cpu_node)
+{
+       struct snd_soc_dai_link *dai_link = simple_priv_to_link(priv, li->link);
+       struct device_node *ep;
+       struct device_node *ports;
+       unsigned int daifmt = 0, daiclk = 0;
+       unsigned int bit_frame = 0;
+
+       /* Need Multi support later */
+       ep = port_to_endpoint(port);
+       ports = of_get_parent(port);
+
+       /*
+        *      ports {
+        * (A)
+        *              port {
+        * (B)
+        *                      endpoint {
+        * (C)
+        *                      };
+        *              };
+        *      };
+        * };
+        */
+       graph_parse_daifmt(ep,    &daifmt, &bit_frame);         /* (C) */
+       graph_parse_daifmt(port,  &daifmt, &bit_frame);         /* (B) */
+       if (of_node_name_eq(ports, "ports"))
+               graph_parse_daifmt(ports, &daifmt, &bit_frame); /* (A) */
+
+       /*
+        * convert bit_frame
+        * We need to flip clock_provider if it was CPU node,
+        * because it is Codec base.
+        */
+       daiclk = snd_soc_daifmt_clock_provider_from_bitmap(bit_frame);
+       if (is_cpu_node)
+               daiclk = snd_soc_daifmt_clock_provider_fliped(daiclk);
+
+       dai_link->dai_fmt       = daifmt | daiclk;
+       dai_link->init          = asoc_simple_dai_init;
+       dai_link->ops           = &graph_ops;
+       if (priv->ops)
+               dai_link->ops   = priv->ops;
+}
+
+int audio_graph2_link_normal(struct asoc_simple_priv *priv,
+                            struct device_node *lnk,
+                            struct link_info *li)
+{
+       struct device_node *cpu_port = lnk;
+       struct device_node *cpu_ep = port_to_endpoint(cpu_port);
+       struct device_node *codec_port = of_graph_get_remote_port(cpu_ep);
+       int ret;
+
+       /*
+        * call Codec first.
+        * see
+        *      __graph_parse_node() :: DAI Naming
+        */
+       ret = graph_parse_node(priv, GRAPH_NORMAL, codec_port, li, 0);
+       if (ret < 0)
+               goto err;
+
+       /*
+        * call CPU, and set DAI Name
+        */
+       ret = graph_parse_node(priv, GRAPH_NORMAL, cpu_port, li, 1);
+       if (ret < 0)
+               goto err;
+
+       graph_link_init(priv, cpu_port, li, 1);
+err:
+       of_node_put(codec_port);
+       of_node_put(cpu_ep);
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(audio_graph2_link_normal);
+
+static int graph_link(struct asoc_simple_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;
+       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 ret;
+}
+
+static int graph_counter(struct device_node *lnk)
+{
+       /* Need Multi support later */
+       return 1;
+}
+
+static int graph_count_normal(struct asoc_simple_priv *priv,
+                             struct device_node *lnk,
+                             struct link_info *li)
+{
+       struct device_node *cpu_port = lnk;
+       struct device_node *cpu_ep = port_to_endpoint(cpu_port);
+       struct device_node *codec_port = of_graph_get_remote_port(cpu_ep);
+
+       /*
+        *      CPU {
+        * =>           lnk: port { endpoint { .. }; };
+        *      };
+        */
+       li->num[li->link].cpus          =
+       li->num[li->link].platforms     = graph_counter(cpu_port);
+       li->num[li->link].codecs        = graph_counter(codec_port);
+
+       of_node_put(cpu_ep);
+       of_node_put(codec_port);
+
+       return 0;
+}
+
+static int graph_count(struct asoc_simple_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;
+       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 ret;
+}
+
+static int graph_for_each_link(struct asoc_simple_priv *priv,
+                              struct graph2_custom_hooks *hooks,
+                              struct link_info *li,
+                              int (*func)(struct asoc_simple_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;
+
+       /* 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)
+                       return ret;
+       }
+
+       return 0;
+}
+
+int audio_graph2_parse_of(struct asoc_simple_priv *priv, struct device *dev,
+                         struct graph2_custom_hooks *hooks)
+{
+       struct snd_soc_card *card = simple_priv_to_card(priv);
+       struct link_info *li;
+       int ret;
+
+       dev_warn(dev, "Audio Graph Card2 is still under Experimental stage\n");
+
+       li = devm_kzalloc(dev, sizeof(*li), GFP_KERNEL);
+       if (!li)
+               return -ENOMEM;
+
+       card->probe     = asoc_graph_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 = asoc_simple_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 = asoc_simple_parse_widgets(card, NULL);
+       if (ret < 0)
+               goto err;
+
+       ret = asoc_simple_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 = asoc_simple_parse_card_name(card, 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;
+       }
+
+       asoc_simple_debug_info(priv);
+
+       ret = devm_snd_soc_register_card(dev, card);
+err:
+       devm_kfree(dev, li);
+
+       if ((ret < 0) && (ret != -EPROBE_DEFER))
+               dev_err(dev, "parse error %d\n", ret);
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(audio_graph2_parse_of);
+
+static int graph_probe(struct platform_device *pdev)
+{
+       struct asoc_simple_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 = asoc_simple_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>");