ASoC: rsnd: SSI supports DMA transfer via BUSIF

This patch adds BUSIF support for R-Car sound DMAEngine transfer.
The sound data will be transferred via FIFO which can cover blank time
which will happen when DMA channel is switching.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

1 files changed, 152 insertions, 2 deletions

diff --git a/sound/soc/sh/rcar/scu.c b/sound/soc/sh/rcar/scu.c
index c12e65f240a..29837e326bc 100644
--- a/sound/soc/sh/rcar/scu.c
+++ b/sound/soc/sh/rcar/scu.c
@@ -15,6 +15,18 @@ struct rsnd_scu {
 	struct rsnd_mod mod;
 };
 
+#define rsnd_scu_mode_flags(p) ((p)->info->flags)
+
+/*
+ * ADINR
+ */
+#define OTBL_24		(0 << 16)
+#define OTBL_22		(2 << 16)
+#define OTBL_20		(4 << 16)
+#define OTBL_18		(6 << 16)
+#define OTBL_16		(8 << 16)
+
+
 #define rsnd_mod_to_scu(_mod)	\
 	container_of((_mod), struct rsnd_scu, mod)
 
@@ -24,6 +36,116 @@ struct rsnd_scu {
 		     ((pos) = (struct rsnd_scu *)(priv)->scu + i);	\
 	     i++)
 
+static int rsnd_scu_set_route(struct rsnd_priv *priv,
+			      struct rsnd_mod *mod,
+			      struct rsnd_dai *rdai,
+			      struct rsnd_dai_stream *io)
+{
+	struct scu_route_config {
+		u32 mask;
+		int shift;
+	} routes[] = {
+		{ 0xF,  0, }, /* 0 */
+		{ 0xF,  4, }, /* 1 */
+		{ 0xF,  8, }, /* 2 */
+		{ 0x7, 12, }, /* 3 */
+		{ 0x7, 16, }, /* 4 */
+		{ 0x7, 20, }, /* 5 */
+		{ 0x7, 24, }, /* 6 */
+		{ 0x3, 28, }, /* 7 */
+		{ 0x3, 30, }, /* 8 */
+	};
+
+	u32 mask;
+	u32 val;
+	int shift;
+	int id;
+
+	/*
+	 * Gen1 only
+	 */
+	if (!rsnd_is_gen1(priv))
+		return 0;
+
+	id = rsnd_mod_id(mod);
+	if (id < 0 || id > ARRAY_SIZE(routes))
+		return -EIO;
+
+	/*
+	 * SRC_ROUTE_SELECT
+	 */
+	val = rsnd_dai_is_play(rdai, io) ? 0x1 : 0x2;
+	val = val		<< routes[id].shift;
+	mask = routes[id].mask	<< routes[id].shift;
+
+	rsnd_mod_bset(mod, SRC_ROUTE_SEL, mask, val);
+
+	/*
+	 * SRC_TIMING_SELECT
+	 */
+	shift	= (id % 4) * 8;
+	mask	= 0x1F << shift;
+	if (8 == id) /* SRU8 is very special */
+		val = id << shift;
+	else
+		val = (id + 1) << shift;
+
+	switch (id / 4) {
+	case 0:
+		rsnd_mod_bset(mod, SRC_TMG_SEL0, mask, val);
+		break;
+	case 1:
+		rsnd_mod_bset(mod, SRC_TMG_SEL1, mask, val);
+		break;
+	case 2:
+		rsnd_mod_bset(mod, SRC_TMG_SEL2, mask, val);
+		break;
+	}
+
+	return 0;
+}
+
+static int rsnd_scu_set_mode(struct rsnd_priv *priv,
+			     struct rsnd_mod *mod,
+			     struct rsnd_dai *rdai,
+			     struct rsnd_dai_stream *io)
+{
+	int id = rsnd_mod_id(mod);
+	u32 val;
+
+	if (rsnd_is_gen1(priv)) {
+		val = (1 << id);
+		rsnd_mod_bset(mod, SRC_CTRL, val, val);
+	}
+
+	return 0;
+}
+
+static int rsnd_scu_set_hpbif(struct rsnd_priv *priv,
+			      struct rsnd_mod *mod,
+			      struct rsnd_dai *rdai,
+			      struct rsnd_dai_stream *io)
+{
+	struct snd_pcm_runtime *runtime = rsnd_io_to_runtime(io);
+	u32 adinr = runtime->channels;
+
+	switch (runtime->sample_bits) {
+	case 16:
+		adinr |= OTBL_16;
+		break;
+	case 32:
+		adinr |= OTBL_24;
+		break;
+	default:
+		return -EIO;
+	}
+
+	rsnd_mod_write(mod, BUSIF_MODE, 1);
+	rsnd_mod_write(mod, BUSIF_ADINR, adinr);
+
+	return 0;
+}
+
 static int rsnd_scu_init(struct rsnd_mod *mod,
 			 struct rsnd_dai *rdai,
 			 struct rsnd_dai_stream *io)
@@ -53,9 +175,36 @@ static int rsnd_scu_start(struct rsnd_mod *mod,
 			  struct rsnd_dai_stream *io)
 {
 	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
+	struct rsnd_scu *scu = rsnd_mod_to_scu(mod);
 	struct device *dev = rsnd_priv_to_dev(priv);
+	u32 flags = rsnd_scu_mode_flags(scu);
+	int ret;
+
+	/*
+	 * SCU will be used if it has RSND_SCU_USB_HPBIF flags
+	 */
+	if (!(flags & RSND_SCU_USB_HPBIF)) {
+		/* it use PIO transter */
+		dev_dbg(dev, "%s%d is not used\n",
+			rsnd_mod_name(mod), rsnd_mod_id(mod));
+
+		return 0;
+	}
+
+	/* it use DMA transter */
+	ret = rsnd_scu_set_route(priv, mod, rdai, io);
+	if (ret < 0)
+		return ret;
+
+	ret = rsnd_scu_set_mode(priv, mod, rdai, io);
+	if (ret < 0)
+		return ret;
 
-	dev_dbg(dev, "%s.%d start\n", rsnd_mod_name(mod), rsnd_mod_id(mod));
+	ret = rsnd_scu_set_hpbif(priv, mod, rdai, io);
+	if (ret < 0)
+		return ret;
+
+	dev_dbg(dev, "%s%d start\n", rsnd_mod_name(mod), rsnd_mod_id(mod));
 
 	return 0;
 }
@@ -112,8 +261,9 @@ int rsnd_scu_probe(struct platform_device *pdev,
 		rsnd_mod_init(priv, &scu->mod,
 			      &rsnd_scu_ops, i);
 		scu->info = &info->scu_info[i];
-	}
 
+		dev_dbg(dev, "SCU%d probed\n", i);
+	}
 	dev_dbg(dev, "scu probed\n");
 
 	return 0;