ASoC: makes CPU/Codec channel connection map more generic

Current ASoC CPU:Codec = N:M connection is using connection mapping idea,
but it is used for N < M case only. We want to use it for any case.

By this patch, not only N:M connection, but all existing connection
(1:1, 1:N, N:N) will use same connection mapping. Then, because it will
use default mapping, no conversion patch is needed to exising drivers.

More over, CPU:Codec = N:M (N > M) also supported in the same time.

ch_maps array will has CPU/Codec index by this patch.

Image
	CPU0 <---> Codec0
	CPU1 <-+-> Codec1
	CPU2 <-/

ch_map
	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

Link: https://lore.kernel.org/r/87fs6wuszr.wl-kuninori.morimoto.gx@renesas.com
Link: https://lore.kernel.org/r/878r7yqeo4.wl-kuninori.morimoto.gx@renesas.com
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Tested-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Tested-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/87ttpq4f2c.wl-kuninori.morimoto.gx@renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 94 insertions, 1 deletions

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 @@ component_dai_empty:
 	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;
 	}