[v7,1/5] ASoC: makes CPU/Codec channel connection map more generic

diff --git a/include/sound/soc.h b/include/sound/soc.h
index 7792c393e238..f3803c2dc349 100644
--- a/include/sound/soc.h
+++ b/include/sound/soc.h
@@ -655,8 +655,45 @@  struct snd_soc_dai_link_component {
 	struct of_phandle_args *dai_args;
 };
 
-struct snd_soc_dai_link_codec_ch_map {
-	unsigned int connected_cpu_id;
+/*
+ * [dai_link->ch_maps Image sample]
+ *
+ *-------------------------
+ * CPU0 <---> Codec0
+ *
+ * ch-map[0].cpu = 0	ch-map[0].codec = 0
+ *
+ *-------------------------
+ * CPU0 <---> Codec0
+ * CPU1 <---> Codec1
+ * CPU2 <---> Codec2
+ *
+ * ch-map[0].cpu = 0	ch-map[0].codec = 0
+ * ch-map[1].cpu = 1	ch-map[1].codec = 1
+ * ch-map[2].cpu = 2	ch-map[2].codec = 2
+ *
+ *-------------------------
+ * CPU0 <---> Codec0
+ * CPU1 <-+-> Codec1
+ * CPU2 <-/
+ *
+ * ch-map[0].cpu = 0	ch-map[0].codec = 0
+ * ch-map[1].cpu = 1	ch-map[1].codec = 1
+ * ch-map[2].cpu = 2	ch-map[2].codec = 1
+ *
+ *-------------------------
+ * CPU0 <---> Codec0
+ * CPU1 <-+-> Codec1
+ *	  \-> Codec2
+ *
+ * ch-map[0].cpu = 0	ch-map[0].codec = 0
+ * ch-map[1].cpu = 1	ch-map[1].codec = 1
+ * ch-map[2].cpu = 1	ch-map[2].codec = 2
+ *
+ */
+struct snd_soc_dai_link_ch_map {
+	unsigned int cpu;
+	unsigned int codec;
 	unsigned int ch_mask;
 };
 
@@ -688,7 +725,9 @@  struct snd_soc_dai_link {
 	struct snd_soc_dai_link_component *codecs;
 	unsigned int num_codecs;
 
-	struct snd_soc_dai_link_codec_ch_map *codec_ch_maps;
+	/* num_ch_maps = max(num_cpu, num_codecs) */
+	struct snd_soc_dai_link_ch_map *ch_maps;
+
 	/*
 	 * You MAY specify the link's platform/PCM/DMA driver, either by
 	 * device name, or by DT/OF node, but not both. Some forms of link
@@ -775,6 +814,10 @@  struct snd_soc_dai_link {
 #endif
 };
 
+static inline int snd_soc_link_num_ch_map(struct snd_soc_dai_link *link) {
+	return max(link->num_cpus, link->num_codecs);
+}
+
 static inline struct snd_soc_dai_link_component*
 snd_soc_link_to_cpu(struct snd_soc_dai_link *link, int n) {
 	return &(link)->cpus[n];
@@ -808,6 +851,12 @@  snd_soc_link_to_platform(struct snd_soc_dai_link *link, int n) {
 		     ((cpu) = snd_soc_link_to_cpu(link, i));		\
 	     (i)++)
 
+#define for_each_link_ch_maps(link, i, ch_map)			\
+	for ((i) = 0;						\
+	     ((i) < snd_soc_link_num_ch_map(link) &&		\
+		      ((ch_map) = link->ch_maps + i));		\
+	     (i)++)
+
 /*
  * Sample 1 : Single CPU/Codec/Platform
  *
@@ -1163,6 +1212,7 @@  struct snd_soc_pcm_runtime {
 	     ((i) < (rtd)->dai_link->num_cpus + (rtd)->dai_link->num_codecs) &&	\
 		     ((dai) = (rtd)->dais[i]);				\
 	     (i)++)
+#define for_each_rtd_ch_maps(rtd, i, ch_maps) for_each_link_ch_maps(rtd->dai_link, i, ch_maps)
 
 void snd_soc_close_delayed_work(struct snd_soc_pcm_runtime *rtd);
 
diff --git a/sound/soc/intel/boards/sof_sdw.c b/sound/soc/intel/boards/sof_sdw.c
index 3312ad8a563b..2faf7372bad0 100644
--- a/sound/soc/intel/boards/sof_sdw.c
+++ b/sound/soc/intel/boards/sof_sdw.c
@@ -570,16 +570,14 @@  int sdw_hw_params(struct snd_pcm_substream *substream,
 		  struct snd_pcm_hw_params *params)
 {
 	struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
+	struct snd_soc_dai_link_ch_map *ch_maps;
 	int ch = params_channels(params);
-	struct snd_soc_dai *codec_dai;
-	struct snd_soc_dai *cpu_dai;
 	unsigned int ch_mask;
 	int num_codecs;
 	int step;
 	int i;
-	int j;
 
-	if (!rtd->dai_link->codec_ch_maps)
+	if (!rtd->dai_link->ch_maps)
 		return 0;
 
 	/* Identical data will be sent to all codecs in playback */
@@ -605,13 +603,9 @@  int sdw_hw_params(struct snd_pcm_substream *substream,
 	 * link has more than one codec DAIs. Set codec channel mask and
 	 * ASoC will set the corresponding channel numbers for each cpu dai.
 	 */
-	for_each_rtd_cpu_dais(rtd, i, cpu_dai) {
-		for_each_rtd_codec_dais(rtd, j, codec_dai) {
-			if (rtd->dai_link->codec_ch_maps[j].connected_cpu_id != i)
-				continue;
-			rtd->dai_link->codec_ch_maps[j].ch_mask = ch_mask << (j * step);
-		}
-	}
+	for_each_link_ch_maps(rtd->dai_link, i, ch_maps)
+		ch_maps->ch_mask = ch_mask << (i * step);
+
 	return 0;
 }
 
@@ -1350,15 +1344,17 @@  static int get_slave_info(const struct snd_soc_acpi_link_adr *adr_link,
 	return 0;
 }
 
-static void set_dailink_map(struct snd_soc_dai_link_codec_ch_map *sdw_codec_ch_maps,
+static void set_dailink_map(struct snd_soc_dai_link_ch_map *sdw_codec_ch_maps,
 			    int codec_num, int cpu_num)
 {
 	int step;
 	int i;
 
 	step = codec_num / cpu_num;
-	for (i = 0; i < codec_num; i++)
-		sdw_codec_ch_maps[i].connected_cpu_id = i / step;
+	for (i = 0; i < codec_num; i++) {
+		sdw_codec_ch_maps[i].cpu	= i / step;
+		sdw_codec_ch_maps[i].codec	= i;
+	}
 }
 
 static const char * const type_strings[] = {"SimpleJack", "SmartAmp", "SmartMic"};
@@ -1453,7 +1449,7 @@  static int create_sdw_dailink(struct snd_soc_card *card, int *link_index,
 		*ignore_pch_dmic = true;
 
 	for_each_pcm_streams(stream) {
-		struct snd_soc_dai_link_codec_ch_map *sdw_codec_ch_maps;
+		struct snd_soc_dai_link_ch_map *sdw_codec_ch_maps;
 		char *name, *cpu_name;
 		int playback, capture;
 		static const char * const sdw_stream_name[] = {
@@ -1530,7 +1526,7 @@  static int create_sdw_dailink(struct snd_soc_card *card, int *link_index,
 		dai_links[*link_index].nonatomic = true;
 
 		set_dailink_map(sdw_codec_ch_maps, codec_num, cpu_dai_num);
-		dai_links[*link_index].codec_ch_maps = sdw_codec_ch_maps;
+		dai_links[*link_index].ch_maps = sdw_codec_ch_maps;
 		ret = set_codec_init_func(card, adr_link, dai_links + (*link_index)++,
 					  playback, group_id, adr_index, dai_index);
 		if (ret < 0) {
diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
index b2bd45e87bc3..4ca3319a8e19 100644
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -1015,6 +1015,94 @@  static int soc_dai_link_sanity_check(struct snd_soc_card *card,
 	return -EINVAL;
 }
 
+#define MAX_DEFAULT_CH_MAP_SIZE 7
+static struct snd_soc_dai_link_ch_map default_ch_map_sync[MAX_DEFAULT_CH_MAP_SIZE] = {
+	{ .cpu = 0, .codec = 0 },
+	{ .cpu = 1, .codec = 1 },
+	{ .cpu = 2, .codec = 2 },
+	{ .cpu = 3, .codec = 3 },
+	{ .cpu = 4, .codec = 4 },
+	{ .cpu = 5, .codec = 5 },
+	{ .cpu = 6, .codec = 6 },
+};
+static struct snd_soc_dai_link_ch_map default_ch_map_1cpu[MAX_DEFAULT_CH_MAP_SIZE] = {
+	{ .cpu = 0, .codec = 0 },
+	{ .cpu = 0, .codec = 1 },
+	{ .cpu = 0, .codec = 2 },
+	{ .cpu = 0, .codec = 3 },
+	{ .cpu = 0, .codec = 4 },
+	{ .cpu = 0, .codec = 5 },
+	{ .cpu = 0, .codec = 6 },
+};
+static struct snd_soc_dai_link_ch_map default_ch_map_1codec[MAX_DEFAULT_CH_MAP_SIZE] = {
+	{ .cpu = 0, .codec = 0 },
+	{ .cpu = 1, .codec = 0 },
+	{ .cpu = 2, .codec = 0 },
+	{ .cpu = 3, .codec = 0 },
+	{ .cpu = 4, .codec = 0 },
+	{ .cpu = 5, .codec = 0 },
+	{ .cpu = 6, .codec = 0 },
+};
+static int snd_soc_compensate_channel_connection_map(struct snd_soc_card *card,
+						     struct snd_soc_dai_link *dai_link)
+{
+	struct snd_soc_dai_link_ch_map *ch_maps;
+	int i;
+
+	/*
+	 * dai_link->ch_maps indicates how CPU/Codec are connected.
+	 * It will be a map seen from a larger number of DAI.
+	 * see
+	 *	soc.h :: [dai_link->ch_maps Image sample]
+	 */
+
+	/* it should have ch_maps if connection was N:M */
+	if (dai_link->num_cpus > 1 && dai_link->num_codecs > 1 &&
+	    dai_link->num_cpus != dai_link->num_codecs && !dai_link->ch_maps) {
+		dev_err(card->dev, "need to have ch_maps when N:M connction (%s)",
+			dai_link->name);
+		return -EINVAL;
+	}
+
+	/* do nothing if it has own maps */
+	if (dai_link->ch_maps)
+		goto sanity_check;
+
+	/* check default map size */
+	if (dai_link->num_cpus   > MAX_DEFAULT_CH_MAP_SIZE ||
+	    dai_link->num_codecs > MAX_DEFAULT_CH_MAP_SIZE) {
+		dev_err(card->dev, "soc-core.c needs update default_connection_maps");
+		return -EINVAL;
+	}
+
+	/* Compensate missing map for ... */
+	if (dai_link->num_cpus == dai_link->num_codecs)
+		dai_link->ch_maps = default_ch_map_sync;	/* for 1:1 or N:N */
+	else if (dai_link->num_cpus <  dai_link->num_codecs)
+		dai_link->ch_maps = default_ch_map_1cpu;	/* for 1:N */
+	else
+		dai_link->ch_maps = default_ch_map_1codec;	/* for N:1 */
+
+sanity_check:
+	dev_dbg(card->dev, "dai_link %s\n", dai_link->stream_name);
+	for_each_link_ch_maps(dai_link, i, ch_maps) {
+		if ((ch_maps->cpu   >= dai_link->num_cpus) ||
+		    (ch_maps->codec >= dai_link->num_codecs)) {
+			dev_err(card->dev,
+				"unexpected dai_link->ch_maps[%d] index (cpu(%d/%d) codec(%d/%d))",
+				i,
+				ch_maps->cpu,	dai_link->num_cpus,
+				ch_maps->codec,	dai_link->num_codecs);
+			return -EINVAL;
+		}
+
+		dev_dbg(card->dev, "  [%d] cpu%d <-> codec%d\n",
+			i, ch_maps->cpu, ch_maps->codec);
+	}
+
+	return 0;
+}
+
 /**
  * snd_soc_remove_pcm_runtime - Remove a pcm_runtime from card
  * @card: The ASoC card to which the pcm_runtime has
@@ -1121,8 +1209,13 @@  int snd_soc_add_pcm_runtimes(struct snd_soc_card *card,
 			     int num_dai_link)
 {
 	for (int i = 0; i < num_dai_link; i++) {
-		int ret = snd_soc_add_pcm_runtime(card, dai_link + i);
+		int ret;
+
+		ret = snd_soc_compensate_channel_connection_map(card, dai_link + i);
+		if (ret < 0)
+			return ret;
 
+		ret = snd_soc_add_pcm_runtime(card, dai_link + i);
 		if (ret < 0)
 			return ret;
 	}
diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c
index 3844f777c87b..3d72084b6a34 100644
--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -4438,11 +4438,14 @@  static void soc_dapm_dai_stream_event(struct snd_soc_dai *dai, int stream,
 void snd_soc_dapm_connect_dai_link_widgets(struct snd_soc_card *card)
 {
 	struct snd_soc_pcm_runtime *rtd;
+	struct snd_soc_dai *cpu_dai;
 	struct snd_soc_dai *codec_dai;
-	int i;
 
 	/* for each BE DAI link... */
 	for_each_card_rtds(card, rtd)  {
+		struct snd_soc_dai_link_ch_map *ch_maps;
+		int i;
+
 		/*
 		 * dynamic FE links have no fixed DAI mapping.
 		 * CODEC<->CODEC links have no direct connection.
@@ -4450,39 +4453,15 @@  void snd_soc_dapm_connect_dai_link_widgets(struct snd_soc_card *card)
 		if (rtd->dai_link->dynamic)
 			continue;
 
-		if (rtd->dai_link->num_cpus == 1) {
-			for_each_rtd_codec_dais(rtd, i, codec_dai)
-				dapm_connect_dai_pair(card, rtd, codec_dai,
-						      snd_soc_rtd_to_cpu(rtd, 0));
-		} else if (rtd->dai_link->num_codecs == rtd->dai_link->num_cpus) {
-			for_each_rtd_codec_dais(rtd, i, codec_dai)
-				dapm_connect_dai_pair(card, rtd, codec_dai,
-						      snd_soc_rtd_to_cpu(rtd, i));
-		} else if (rtd->dai_link->num_codecs > rtd->dai_link->num_cpus) {
-			int cpu_id;
-
-			if (!rtd->dai_link->codec_ch_maps) {
-				dev_err(card->dev, "%s: no codec channel mapping table provided\n",
-					__func__);
-				continue;
-			}
+		/*
+		 * see
+		 *	soc.h :: [dai_link->ch_maps Image sample]
+		 */
+		for_each_rtd_ch_maps(rtd, i, ch_maps) {
+			cpu_dai   = snd_soc_rtd_to_cpu(rtd,   ch_maps->cpu);
+			codec_dai = snd_soc_rtd_to_codec(rtd, ch_maps->codec);
 
-			for_each_rtd_codec_dais(rtd, i, codec_dai) {
-				cpu_id = rtd->dai_link->codec_ch_maps[i].connected_cpu_id;
-				if (cpu_id >= rtd->dai_link->num_cpus) {
-					dev_err(card->dev,
-						"%s: dai_link %s cpu_id %d too large, num_cpus is %d\n",
-						__func__, rtd->dai_link->name, cpu_id,
-						rtd->dai_link->num_cpus);
-					continue;
-				}
-				dapm_connect_dai_pair(card, rtd, codec_dai,
-						      snd_soc_rtd_to_cpu(rtd, cpu_id));
-			}
-		} else {
-			dev_err(card->dev,
-				"%s: codec number %d < cpu number %d is not supported\n",
-				__func__, rtd->dai_link->num_codecs, rtd->dai_link->num_cpus);
+			dapm_connect_dai_pair(card, rtd, codec_dai, cpu_dai);
 		}
 	}
 }
diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c
index 323e4d7b6adf..c20573aeb756 100644
--- a/sound/soc/soc-pcm.c
+++ b/sound/soc/soc-pcm.c
@@ -1050,6 +1050,7 @@  static int __soc_pcm_hw_params(struct snd_soc_pcm_runtime *rtd,
 	}
 
 	for_each_rtd_cpu_dais(rtd, i, cpu_dai) {
+		struct snd_soc_dai_link_ch_map *ch_maps;
 		unsigned int ch_mask = 0;
 		int j;
 
@@ -1063,22 +1064,20 @@  static int __soc_pcm_hw_params(struct snd_soc_pcm_runtime *rtd,
 		/* copy params for each cpu */
 		tmp_params = *params;
 
-		if (!rtd->dai_link->codec_ch_maps)
-			goto hw_params;
 		/*
 		 * construct cpu channel mask by combining ch_mask of each
 		 * codec which maps to the cpu.
+		 * see
+		 *	soc.h :: [dai_link->ch_maps Image sample]
 		 */
-		for_each_rtd_codec_dais(rtd, j, codec_dai) {
-			if (rtd->dai_link->codec_ch_maps[j].connected_cpu_id == i)
-				ch_mask |= rtd->dai_link->codec_ch_maps[j].ch_mask;
-		}
+		for_each_rtd_ch_maps(rtd, j, ch_maps)
+			if (ch_maps->cpu == i)
+				ch_mask |= ch_maps->ch_mask;
 
 		/* fixup cpu channel number */
 		if (ch_mask)
 			soc_pcm_codec_params_fixup(&tmp_params, ch_mask);
 
-hw_params:
 		ret = snd_soc_dai_hw_params(cpu_dai, substream, &tmp_params);
 		if (ret < 0)
 			goto out;
@@ -2826,35 +2825,20 @@  static int soc_get_playback_capture(struct snd_soc_pcm_runtime *rtd,
 			}
 		}
 	} else {
+		struct snd_soc_dai_link_ch_map *ch_maps;
 		struct snd_soc_dai *codec_dai;
 
 		/* Adapt stream for codec2codec links */
 		int cpu_capture  = snd_soc_get_stream_cpu(dai_link, SNDRV_PCM_STREAM_CAPTURE);
 		int cpu_playback = snd_soc_get_stream_cpu(dai_link, SNDRV_PCM_STREAM_PLAYBACK);
 
-		for_each_rtd_codec_dais(rtd, i, codec_dai) {
-			if (dai_link->num_cpus == 1) {
-				cpu_dai = snd_soc_rtd_to_cpu(rtd, 0);
-			} else if (dai_link->num_cpus == dai_link->num_codecs) {
-				cpu_dai = snd_soc_rtd_to_cpu(rtd, i);
-			} else if (rtd->dai_link->num_codecs > rtd->dai_link->num_cpus) {
-				int cpu_id;
-
-				if (!rtd->dai_link->codec_ch_maps) {
-					dev_err(rtd->card->dev, "%s: no codec channel mapping table provided\n",
-						__func__);
-					return -EINVAL;
-				}
-
-				cpu_id = rtd->dai_link->codec_ch_maps[i].connected_cpu_id;
-				cpu_dai = snd_soc_rtd_to_cpu(rtd, cpu_id);
-			} else {
-				dev_err(rtd->card->dev,
-					"%s codec number %d < cpu number %d is not supported\n",
-					__func__, rtd->dai_link->num_codecs,
-					rtd->dai_link->num_cpus);
-				return -EINVAL;
-			}
+		/*
+		 * see
+		 *	soc.h :: [dai_link->ch_maps Image sample]
+		 */
+		for_each_rtd_ch_maps(rtd, i, ch_maps) {
+			cpu_dai	  = snd_soc_rtd_to_cpu(rtd,   ch_maps->cpu);
+			codec_dai = snd_soc_rtd_to_codec(rtd, ch_maps->codec);
 
 			if (snd_soc_dai_stream_valid(codec_dai, SNDRV_PCM_STREAM_PLAYBACK) &&
 			    snd_soc_dai_stream_valid(cpu_dai,   cpu_playback))