Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 802 insertions, 0 deletions

diff --git a/sound/soc/sh/rcar/dma.c b/sound/soc/sh/rcar/dma.c
new file mode 100644
index 000000000..d65ea7bc4
--- /dev/null
+++ b/sound/soc/sh/rcar/dma.c
@@ -0,0 +1,802 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Renesas R-Car Audio DMAC support
+//
+// Copyright (C) 2015 Renesas Electronics Corp.
+// Copyright (c) 2015 Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
+
+#include <linux/delay.h>
+#include <linux/of_dma.h>
+#include "rsnd.h"
+
+/*
+ * Audio DMAC peri peri register
+ */
+#define PDMASAR		0x00
+#define PDMADAR		0x04
+#define PDMACHCR	0x0c
+
+/* PDMACHCR */
+#define PDMACHCR_DE		(1 << 0)
+
+
+struct rsnd_dmaen {
+	struct dma_chan		*chan;
+	dma_cookie_t		cookie;
+	unsigned int		dma_len;
+};
+
+struct rsnd_dmapp {
+	int			dmapp_id;
+	u32			chcr;
+};
+
+struct rsnd_dma {
+	struct rsnd_mod		mod;
+	struct rsnd_mod		*mod_from;
+	struct rsnd_mod		*mod_to;
+	dma_addr_t		src_addr;
+	dma_addr_t		dst_addr;
+	union {
+		struct rsnd_dmaen en;
+		struct rsnd_dmapp pp;
+	} dma;
+};
+
+struct rsnd_dma_ctrl {
+	void __iomem *base;
+	int dmaen_num;
+	int dmapp_num;
+};
+
+#define rsnd_priv_to_dmac(p)	((struct rsnd_dma_ctrl *)(p)->dma)
+#define rsnd_mod_to_dma(_mod) container_of((_mod), struct rsnd_dma, mod)
+#define rsnd_dma_to_dmaen(dma)	(&(dma)->dma.en)
+#define rsnd_dma_to_dmapp(dma)	(&(dma)->dma.pp)
+
+/* for DEBUG */
+static struct rsnd_mod_ops mem_ops = {
+	.name = "mem",
+};
+
+static struct rsnd_mod mem = {
+};
+
+/*
+ *		Audio DMAC
+ */
+static void __rsnd_dmaen_complete(struct rsnd_mod *mod,
+				  struct rsnd_dai_stream *io)
+{
+	if (rsnd_io_is_working(io))
+		rsnd_dai_period_elapsed(io);
+}
+
+static void rsnd_dmaen_complete(void *data)
+{
+	struct rsnd_mod *mod = data;
+
+	rsnd_mod_interrupt(mod, __rsnd_dmaen_complete);
+}
+
+static struct dma_chan *rsnd_dmaen_request_channel(struct rsnd_dai_stream *io,
+						   struct rsnd_mod *mod_from,
+						   struct rsnd_mod *mod_to)
+{
+	if ((!mod_from && !mod_to) ||
+	    (mod_from && mod_to))
+		return NULL;
+
+	if (mod_from)
+		return rsnd_mod_dma_req(io, mod_from);
+	else
+		return rsnd_mod_dma_req(io, mod_to);
+}
+
+static int rsnd_dmaen_stop(struct rsnd_mod *mod,
+			   struct rsnd_dai_stream *io,
+			   struct rsnd_priv *priv)
+{
+	struct rsnd_dma *dma = rsnd_mod_to_dma(mod);
+	struct rsnd_dmaen *dmaen = rsnd_dma_to_dmaen(dma);
+
+	if (dmaen->chan)
+		dmaengine_terminate_all(dmaen->chan);
+
+	return 0;
+}
+
+static int rsnd_dmaen_nolock_stop(struct rsnd_mod *mod,
+				   struct rsnd_dai_stream *io,
+				   struct rsnd_priv *priv)
+{
+	struct rsnd_dma *dma = rsnd_mod_to_dma(mod);
+	struct rsnd_dmaen *dmaen = rsnd_dma_to_dmaen(dma);
+
+	/*
+	 * DMAEngine release uses mutex lock.
+	 * Thus, it shouldn't be called under spinlock.
+	 * Let's call it under nolock_start
+	 */
+	if (dmaen->chan)
+		dma_release_channel(dmaen->chan);
+
+	dmaen->chan = NULL;
+
+	return 0;
+}
+
+static int rsnd_dmaen_nolock_start(struct rsnd_mod *mod,
+			    struct rsnd_dai_stream *io,
+			    struct rsnd_priv *priv)
+{
+	struct rsnd_dma *dma = rsnd_mod_to_dma(mod);
+	struct rsnd_dmaen *dmaen = rsnd_dma_to_dmaen(dma);
+	struct device *dev = rsnd_priv_to_dev(priv);
+
+	if (dmaen->chan) {
+		dev_err(dev, "it already has dma channel\n");
+		return -EIO;
+	}
+
+	/*
+	 * DMAEngine request uses mutex lock.
+	 * Thus, it shouldn't be called under spinlock.
+	 * Let's call it under nolock_start
+	 */
+	dmaen->chan = rsnd_dmaen_request_channel(io,
+						 dma->mod_from,
+						 dma->mod_to);
+	if (IS_ERR_OR_NULL(dmaen->chan)) {
+		dmaen->chan = NULL;
+		dev_err(dev, "can't get dma channel\n");
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int rsnd_dmaen_start(struct rsnd_mod *mod,
+			    struct rsnd_dai_stream *io,
+			    struct rsnd_priv *priv)
+{
+	struct rsnd_dma *dma = rsnd_mod_to_dma(mod);
+	struct rsnd_dmaen *dmaen = rsnd_dma_to_dmaen(dma);
+	struct snd_pcm_substream *substream = io->substream;
+	struct device *dev = rsnd_priv_to_dev(priv);
+	struct dma_async_tx_descriptor *desc;
+	struct dma_slave_config cfg = {};
+	int is_play = rsnd_io_is_play(io);
+	int ret;
+
+	cfg.direction	= is_play ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM;
+	cfg.src_addr	= dma->src_addr;
+	cfg.dst_addr	= dma->dst_addr;
+	cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+	cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+
+	dev_dbg(dev, "%s[%d] %pad -> %pad\n",
+		rsnd_mod_name(mod), rsnd_mod_id(mod),
+		&cfg.src_addr, &cfg.dst_addr);
+
+	ret = dmaengine_slave_config(dmaen->chan, &cfg);
+	if (ret < 0)
+		return ret;
+
+	desc = dmaengine_prep_dma_cyclic(dmaen->chan,
+					 substream->runtime->dma_addr,
+					 snd_pcm_lib_buffer_bytes(substream),
+					 snd_pcm_lib_period_bytes(substream),
+					 is_play ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM,
+					 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+
+	if (!desc) {
+		dev_err(dev, "dmaengine_prep_slave_sg() fail\n");
+		return -EIO;
+	}
+
+	desc->callback		= rsnd_dmaen_complete;
+	desc->callback_param	= rsnd_mod_get(dma);
+
+	dmaen->dma_len		= snd_pcm_lib_buffer_bytes(substream);
+
+	dmaen->cookie = dmaengine_submit(desc);
+	if (dmaen->cookie < 0) {
+		dev_err(dev, "dmaengine_submit() fail\n");
+		return -EIO;
+	}
+
+	dma_async_issue_pending(dmaen->chan);
+
+	return 0;
+}
+
+struct dma_chan *rsnd_dma_request_channel(struct device_node *of_node,
+					  struct rsnd_mod *mod, char *name)
+{
+	struct dma_chan *chan = NULL;
+	struct device_node *np;
+	int i = 0;
+
+	for_each_child_of_node(of_node, np) {
+		if (i == rsnd_mod_id(mod) && (!chan))
+			chan = of_dma_request_slave_channel(np, name);
+		i++;
+	}
+
+	/* It should call of_node_put(), since, it is rsnd_xxx_of_node() */
+	of_node_put(of_node);
+
+	return chan;
+}
+
+static int rsnd_dmaen_attach(struct rsnd_dai_stream *io,
+			   struct rsnd_dma *dma,
+			   struct rsnd_mod *mod_from, struct rsnd_mod *mod_to)
+{
+	struct rsnd_priv *priv = rsnd_io_to_priv(io);
+	struct rsnd_dma_ctrl *dmac = rsnd_priv_to_dmac(priv);
+	struct dma_chan *chan;
+
+	/* try to get DMAEngine channel */
+	chan = rsnd_dmaen_request_channel(io, mod_from, mod_to);
+	if (IS_ERR_OR_NULL(chan)) {
+		/* Let's follow when -EPROBE_DEFER case */
+		if (PTR_ERR(chan) == -EPROBE_DEFER)
+			return PTR_ERR(chan);
+
+		/*
+		 * DMA failed. try to PIO mode
+		 * see
+		 *	rsnd_ssi_fallback()
+		 *	rsnd_rdai_continuance_probe()
+		 */
+		return -EAGAIN;
+	}
+
+	/*
+	 * use it for IPMMU if needed
+	 * see
+	 *	rsnd_preallocate_pages()
+	 */
+	io->dmac_dev = chan->device->dev;
+
+	dma_release_channel(chan);
+
+	dmac->dmaen_num++;
+
+	return 0;
+}
+
+static int rsnd_dmaen_pointer(struct rsnd_mod *mod,
+			      struct rsnd_dai_stream *io,
+			      snd_pcm_uframes_t *pointer)
+{
+	struct snd_pcm_runtime *runtime = rsnd_io_to_runtime(io);
+	struct rsnd_dma *dma = rsnd_mod_to_dma(mod);
+	struct rsnd_dmaen *dmaen = rsnd_dma_to_dmaen(dma);
+	struct dma_tx_state state;
+	enum dma_status status;
+	unsigned int pos = 0;
+
+	status = dmaengine_tx_status(dmaen->chan, dmaen->cookie, &state);
+	if (status == DMA_IN_PROGRESS || status == DMA_PAUSED) {
+		if (state.residue > 0 && state.residue <= dmaen->dma_len)
+			pos = dmaen->dma_len - state.residue;
+	}
+	*pointer = bytes_to_frames(runtime, pos);
+
+	return 0;
+}
+
+static struct rsnd_mod_ops rsnd_dmaen_ops = {
+	.name	= "audmac",
+	.nolock_start = rsnd_dmaen_nolock_start,
+	.nolock_stop  = rsnd_dmaen_nolock_stop,
+	.start	= rsnd_dmaen_start,
+	.stop	= rsnd_dmaen_stop,
+	.pointer= rsnd_dmaen_pointer,
+};
+
+/*
+ *		Audio DMAC peri peri
+ */
+static const u8 gen2_id_table_ssiu[] = {
+	0x00, /* SSI00 */
+	0x04, /* SSI10 */
+	0x08, /* SSI20 */
+	0x0c, /* SSI3  */
+	0x0d, /* SSI4  */
+	0x0e, /* SSI5  */
+	0x0f, /* SSI6  */
+	0x10, /* SSI7  */
+	0x11, /* SSI8  */
+	0x12, /* SSI90 */
+};
+static const u8 gen2_id_table_scu[] = {
+	0x2d, /* SCU_SRCI0 */
+	0x2e, /* SCU_SRCI1 */
+	0x2f, /* SCU_SRCI2 */
+	0x30, /* SCU_SRCI3 */
+	0x31, /* SCU_SRCI4 */
+	0x32, /* SCU_SRCI5 */
+	0x33, /* SCU_SRCI6 */
+	0x34, /* SCU_SRCI7 */
+	0x35, /* SCU_SRCI8 */
+	0x36, /* SCU_SRCI9 */
+};
+static const u8 gen2_id_table_cmd[] = {
+	0x37, /* SCU_CMD0 */
+	0x38, /* SCU_CMD1 */
+};
+
+static u32 rsnd_dmapp_get_id(struct rsnd_dai_stream *io,
+			     struct rsnd_mod *mod)
+{
+	struct rsnd_mod *ssi = rsnd_io_to_mod_ssi(io);
+	struct rsnd_mod *src = rsnd_io_to_mod_src(io);
+	struct rsnd_mod *dvc = rsnd_io_to_mod_dvc(io);
+	const u8 *entry = NULL;
+	int id = rsnd_mod_id(mod);
+	int size = 0;
+
+	if (mod == ssi) {
+		entry = gen2_id_table_ssiu;
+		size = ARRAY_SIZE(gen2_id_table_ssiu);
+	} else if (mod == src) {
+		entry = gen2_id_table_scu;
+		size = ARRAY_SIZE(gen2_id_table_scu);
+	} else if (mod == dvc) {
+		entry = gen2_id_table_cmd;
+		size = ARRAY_SIZE(gen2_id_table_cmd);
+	}
+
+	if ((!entry) || (size <= id)) {
+		struct device *dev = rsnd_priv_to_dev(rsnd_io_to_priv(io));
+
+		dev_err(dev, "unknown connection (%s[%d])\n",
+			rsnd_mod_name(mod), rsnd_mod_id(mod));
+
+		/* use non-prohibited SRS number as error */
+		return 0x00; /* SSI00 */
+	}
+
+	return entry[id];
+}
+
+static u32 rsnd_dmapp_get_chcr(struct rsnd_dai_stream *io,
+			       struct rsnd_mod *mod_from,
+			       struct rsnd_mod *mod_to)
+{
+	return	(rsnd_dmapp_get_id(io, mod_from) << 24) +
+		(rsnd_dmapp_get_id(io, mod_to) << 16);
+}
+
+#define rsnd_dmapp_addr(dmac, dma, reg) \
+	(dmac->base + 0x20 + reg + \
+	 (0x10 * rsnd_dma_to_dmapp(dma)->dmapp_id))
+static void rsnd_dmapp_write(struct rsnd_dma *dma, u32 data, u32 reg)
+{
+	struct rsnd_mod *mod = rsnd_mod_get(dma);
+	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
+	struct rsnd_dma_ctrl *dmac = rsnd_priv_to_dmac(priv);
+	struct device *dev = rsnd_priv_to_dev(priv);
+
+	dev_dbg(dev, "w %p : %08x\n", rsnd_dmapp_addr(dmac, dma, reg), data);
+
+	iowrite32(data, rsnd_dmapp_addr(dmac, dma, reg));
+}
+
+static u32 rsnd_dmapp_read(struct rsnd_dma *dma, u32 reg)
+{
+	struct rsnd_mod *mod = rsnd_mod_get(dma);
+	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
+	struct rsnd_dma_ctrl *dmac = rsnd_priv_to_dmac(priv);
+
+	return ioread32(rsnd_dmapp_addr(dmac, dma, reg));
+}
+
+static void rsnd_dmapp_bset(struct rsnd_dma *dma, u32 data, u32 mask, u32 reg)
+{
+	struct rsnd_mod *mod = rsnd_mod_get(dma);
+	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
+	struct rsnd_dma_ctrl *dmac = rsnd_priv_to_dmac(priv);
+	void __iomem *addr = rsnd_dmapp_addr(dmac, dma, reg);
+	u32 val = ioread32(addr);
+
+	val &= ~mask;
+	val |= (data & mask);
+
+	iowrite32(val, addr);
+}
+
+static int rsnd_dmapp_stop(struct rsnd_mod *mod,
+			   struct rsnd_dai_stream *io,
+			   struct rsnd_priv *priv)
+{
+	struct rsnd_dma *dma = rsnd_mod_to_dma(mod);
+	int i;
+
+	rsnd_dmapp_bset(dma, 0,  PDMACHCR_DE, PDMACHCR);
+
+	for (i = 0; i < 1024; i++) {
+		if (0 == (rsnd_dmapp_read(dma, PDMACHCR) & PDMACHCR_DE))
+			return 0;
+		udelay(1);
+	}
+
+	return -EIO;
+}
+
+static int rsnd_dmapp_start(struct rsnd_mod *mod,
+			    struct rsnd_dai_stream *io,
+			    struct rsnd_priv *priv)
+{
+	struct rsnd_dma *dma = rsnd_mod_to_dma(mod);
+	struct rsnd_dmapp *dmapp = rsnd_dma_to_dmapp(dma);
+
+	rsnd_dmapp_write(dma, dma->src_addr,	PDMASAR);
+	rsnd_dmapp_write(dma, dma->dst_addr,	PDMADAR);
+	rsnd_dmapp_write(dma, dmapp->chcr,	PDMACHCR);
+
+	return 0;
+}
+
+static int rsnd_dmapp_attach(struct rsnd_dai_stream *io,
+			     struct rsnd_dma *dma,
+			     struct rsnd_mod *mod_from, struct rsnd_mod *mod_to)
+{
+	struct rsnd_dmapp *dmapp = rsnd_dma_to_dmapp(dma);
+	struct rsnd_priv *priv = rsnd_io_to_priv(io);
+	struct rsnd_dma_ctrl *dmac = rsnd_priv_to_dmac(priv);
+	struct device *dev = rsnd_priv_to_dev(priv);
+
+	dmapp->dmapp_id = dmac->dmapp_num;
+	dmapp->chcr = rsnd_dmapp_get_chcr(io, mod_from, mod_to) | PDMACHCR_DE;
+
+	dmac->dmapp_num++;
+
+	dev_dbg(dev, "id/src/dst/chcr = %d/%pad/%pad/%08x\n",
+		dmapp->dmapp_id, &dma->src_addr, &dma->dst_addr, dmapp->chcr);
+
+	return 0;
+}
+
+static struct rsnd_mod_ops rsnd_dmapp_ops = {
+	.name	= "audmac-pp",
+	.start	= rsnd_dmapp_start,
+	.stop	= rsnd_dmapp_stop,
+	.quit	= rsnd_dmapp_stop,
+};
+
+/*
+ *		Common DMAC Interface
+ */
+
+/*
+ *	DMA read/write register offset
+ *
+ *	RSND_xxx_I_N	for Audio DMAC input
+ *	RSND_xxx_O_N	for Audio DMAC output
+ *	RSND_xxx_I_P	for Audio DMAC peri peri input
+ *	RSND_xxx_O_P	for Audio DMAC peri peri output
+ *
+ *	ex) R-Car H2 case
+ *	      mod        / DMAC in    / DMAC out   / DMAC PP in / DMAC pp out
+ *	SSI : 0xec541000 / 0xec241008 / 0xec24100c
+ *	SSIU: 0xec541000 / 0xec100000 / 0xec100000 / 0xec400000 / 0xec400000
+ *	SCU : 0xec500000 / 0xec000000 / 0xec004000 / 0xec300000 / 0xec304000
+ *	CMD : 0xec500000 /            / 0xec008000                0xec308000
+ */
+#define RDMA_SSI_I_N(addr, i)	(addr ##_reg - 0x00300000 + (0x40 * i) + 0x8)
+#define RDMA_SSI_O_N(addr, i)	(addr ##_reg - 0x00300000 + (0x40 * i) + 0xc)
+
+#define RDMA_SSIU_I_N(addr, i)	(addr ##_reg - 0x00441000 + (0x1000 * i))
+#define RDMA_SSIU_O_N(addr, i)	(addr ##_reg - 0x00441000 + (0x1000 * i))
+
+#define RDMA_SSIU_I_P(addr, i)	(addr ##_reg - 0x00141000 + (0x1000 * i))
+#define RDMA_SSIU_O_P(addr, i)	(addr ##_reg - 0x00141000 + (0x1000 * i))
+
+#define RDMA_SRC_I_N(addr, i)	(addr ##_reg - 0x00500000 + (0x400 * i))
+#define RDMA_SRC_O_N(addr, i)	(addr ##_reg - 0x004fc000 + (0x400 * i))
+
+#define RDMA_SRC_I_P(addr, i)	(addr ##_reg - 0x00200000 + (0x400 * i))
+#define RDMA_SRC_O_P(addr, i)	(addr ##_reg - 0x001fc000 + (0x400 * i))
+
+#define RDMA_CMD_O_N(addr, i)	(addr ##_reg - 0x004f8000 + (0x400 * i))
+#define RDMA_CMD_O_P(addr, i)	(addr ##_reg - 0x001f8000 + (0x400 * i))
+
+static dma_addr_t
+rsnd_gen2_dma_addr(struct rsnd_dai_stream *io,
+		   struct rsnd_mod *mod,
+		   int is_play, int is_from)
+{
+	struct rsnd_priv *priv = rsnd_io_to_priv(io);
+	struct device *dev = rsnd_priv_to_dev(priv);
+	phys_addr_t ssi_reg = rsnd_gen_get_phy_addr(priv, RSND_GEN2_SSI);
+	phys_addr_t src_reg = rsnd_gen_get_phy_addr(priv, RSND_GEN2_SCU);
+	int is_ssi = !!(rsnd_io_to_mod_ssi(io) == mod);
+	int use_src = !!rsnd_io_to_mod_src(io);
+	int use_cmd = !!rsnd_io_to_mod_dvc(io) ||
+		      !!rsnd_io_to_mod_mix(io) ||
+		      !!rsnd_io_to_mod_ctu(io);
+	int id = rsnd_mod_id(mod);
+	struct dma_addr {
+		dma_addr_t out_addr;
+		dma_addr_t in_addr;
+	} dma_addrs[3][2][3] = {
+		/* SRC */
+		/* Capture */
+		{{{ 0,				0 },
+		  { RDMA_SRC_O_N(src, id),	RDMA_SRC_I_P(src, id) },
+		  { RDMA_CMD_O_N(src, id),	RDMA_SRC_I_P(src, id) } },
+		 /* Playback */
+		 {{ 0,				0, },
+		  { RDMA_SRC_O_P(src, id),	RDMA_SRC_I_N(src, id) },
+		  { RDMA_CMD_O_P(src, id),	RDMA_SRC_I_N(src, id) } }
+		},
+		/* SSI */
+		/* Capture */
+		{{{ RDMA_SSI_O_N(ssi, id),	0 },
+		  { RDMA_SSIU_O_P(ssi, id),	0 },
+		  { RDMA_SSIU_O_P(ssi, id),	0 } },
+		 /* Playback */
+		 {{ 0,				RDMA_SSI_I_N(ssi, id) },
+		  { 0,				RDMA_SSIU_I_P(ssi, id) },
+		  { 0,				RDMA_SSIU_I_P(ssi, id) } }
+		},
+		/* SSIU */
+		/* Capture */
+		{{{ RDMA_SSIU_O_N(ssi, id),	0 },
+		  { RDMA_SSIU_O_P(ssi, id),	0 },
+		  { RDMA_SSIU_O_P(ssi, id),	0 } },
+		 /* Playback */
+		 {{ 0,				RDMA_SSIU_I_N(ssi, id) },
+		  { 0,				RDMA_SSIU_I_P(ssi, id) },
+		  { 0,				RDMA_SSIU_I_P(ssi, id) } } },
+	};
+
+	/* it shouldn't happen */
+	if (use_cmd && !use_src)
+		dev_err(dev, "DVC is selected without SRC\n");
+
+	/* use SSIU or SSI ? */
+	if (is_ssi && rsnd_ssi_use_busif(io))
+		is_ssi++;
+
+	return (is_from) ?
+		dma_addrs[is_ssi][is_play][use_src + use_cmd].out_addr :
+		dma_addrs[is_ssi][is_play][use_src + use_cmd].in_addr;
+}
+
+static dma_addr_t rsnd_dma_addr(struct rsnd_dai_stream *io,
+				struct rsnd_mod *mod,
+				int is_play, int is_from)
+{
+	struct rsnd_priv *priv = rsnd_io_to_priv(io);
+
+	/*
+	 * gen1 uses default DMA addr
+	 */
+	if (rsnd_is_gen1(priv))
+		return 0;
+
+	if (!mod)
+		return 0;
+
+	return rsnd_gen2_dma_addr(io, mod, is_play, is_from);
+}
+
+#define MOD_MAX (RSND_MOD_MAX + 1) /* +Memory */
+static void rsnd_dma_of_path(struct rsnd_mod *this,
+			     struct rsnd_dai_stream *io,
+			     int is_play,
+			     struct rsnd_mod **mod_from,
+			     struct rsnd_mod **mod_to)
+{
+	struct rsnd_mod *ssi = rsnd_io_to_mod_ssi(io);
+	struct rsnd_mod *src = rsnd_io_to_mod_src(io);
+	struct rsnd_mod *ctu = rsnd_io_to_mod_ctu(io);
+	struct rsnd_mod *mix = rsnd_io_to_mod_mix(io);
+	struct rsnd_mod *dvc = rsnd_io_to_mod_dvc(io);
+	struct rsnd_mod *mod[MOD_MAX];
+	struct rsnd_mod *mod_start, *mod_end;
+	struct rsnd_priv *priv = rsnd_mod_to_priv(this);
+	struct device *dev = rsnd_priv_to_dev(priv);
+	int nr, i, idx;
+
+	if (!ssi)
+		return;
+
+	nr = 0;
+	for (i = 0; i < MOD_MAX; i++) {
+		mod[i] = NULL;
+		nr += !!rsnd_io_to_mod(io, i);
+	}
+
+	/*
+	 * [S] -*-> [E]
+	 * [S] -*-> SRC -o-> [E]
+	 * [S] -*-> SRC -> DVC -o-> [E]
+	 * [S] -*-> SRC -> CTU -> MIX -> DVC -o-> [E]
+	 *
+	 * playback	[S] = mem
+	 *		[E] = SSI
+	 *
+	 * capture	[S] = SSI
+	 *		[E] = mem
+	 *
+	 * -*->		Audio DMAC
+	 * -o->		Audio DMAC peri peri
+	 */
+	mod_start	= (is_play) ? NULL : ssi;
+	mod_end		= (is_play) ? ssi  : NULL;
+
+	idx = 0;
+	mod[idx++] = mod_start;
+	for (i = 1; i < nr; i++) {
+		if (src) {
+			mod[idx++] = src;
+			src = NULL;
+		} else if (ctu) {
+			mod[idx++] = ctu;
+			ctu = NULL;
+		} else if (mix) {
+			mod[idx++] = mix;
+			mix = NULL;
+		} else if (dvc) {
+			mod[idx++] = dvc;
+			dvc = NULL;
+		}
+	}
+	mod[idx] = mod_end;
+
+	/*
+	 *		| SSI | SRC |
+	 * -------------+-----+-----+
+	 *  is_play	|  o  |  *  |
+	 * !is_play	|  *  |  o  |
+	 */
+	if ((this == ssi) == (is_play)) {
+		*mod_from	= mod[idx - 1];
+		*mod_to		= mod[idx];
+	} else {
+		*mod_from	= mod[0];
+		*mod_to		= mod[1];
+	}
+
+	dev_dbg(dev, "module connection (this is %s[%d])\n",
+		rsnd_mod_name(this), rsnd_mod_id(this));
+	for (i = 0; i <= idx; i++) {
+		dev_dbg(dev, "  %s[%d]%s\n",
+			rsnd_mod_name(mod[i] ? mod[i] : &mem),
+			rsnd_mod_id  (mod[i] ? mod[i] : &mem),
+			(mod[i] == *mod_from) ? " from" :
+			(mod[i] == *mod_to)   ? " to" : "");
+	}
+}
+
+static int rsnd_dma_alloc(struct rsnd_dai_stream *io, struct rsnd_mod *mod,
+			  struct rsnd_mod **dma_mod)
+{
+	struct rsnd_mod *mod_from = NULL;
+	struct rsnd_mod *mod_to = NULL;
+	struct rsnd_priv *priv = rsnd_io_to_priv(io);
+	struct rsnd_dma_ctrl *dmac = rsnd_priv_to_dmac(priv);
+	struct device *dev = rsnd_priv_to_dev(priv);
+	struct rsnd_dma *dma;
+	struct rsnd_mod_ops *ops;
+	enum rsnd_mod_type type;
+	int (*attach)(struct rsnd_dai_stream *io, struct rsnd_dma *dma,
+		      struct rsnd_mod *mod_from, struct rsnd_mod *mod_to);
+	int is_play = rsnd_io_is_play(io);
+	int ret, dma_id;
+
+	/*
+	 * DMA failed. try to PIO mode
+	 * see
+	 *	rsnd_ssi_fallback()
+	 *	rsnd_rdai_continuance_probe()
+	 */
+	if (!dmac)
+		return -EAGAIN;
+
+	rsnd_dma_of_path(mod, io, is_play, &mod_from, &mod_to);
+
+	/* for Gen2 or later */
+	if (mod_from && mod_to) {
+		ops	= &rsnd_dmapp_ops;
+		attach	= rsnd_dmapp_attach;
+		dma_id	= dmac->dmapp_num;
+		type	= RSND_MOD_AUDMAPP;
+	} else {
+		ops	= &rsnd_dmaen_ops;
+		attach	= rsnd_dmaen_attach;
+		dma_id	= dmac->dmaen_num;
+		type	= RSND_MOD_AUDMA;
+	}
+
+	/* for Gen1, overwrite */
+	if (rsnd_is_gen1(priv)) {
+		ops	= &rsnd_dmaen_ops;
+		attach	= rsnd_dmaen_attach;
+		dma_id	= dmac->dmaen_num;
+		type	= RSND_MOD_AUDMA;
+	}
+
+	dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL);
+	if (!dma)
+		return -ENOMEM;
+
+	*dma_mod = rsnd_mod_get(dma);
+
+	ret = rsnd_mod_init(priv, *dma_mod, ops, NULL,
+			    rsnd_mod_get_status, type, dma_id);
+	if (ret < 0)
+		return ret;
+
+	dev_dbg(dev, "%s[%d] %s[%d] -> %s[%d]\n",
+		rsnd_mod_name(*dma_mod), rsnd_mod_id(*dma_mod),
+		rsnd_mod_name(mod_from ? mod_from : &mem),
+		rsnd_mod_id  (mod_from ? mod_from : &mem),
+		rsnd_mod_name(mod_to   ? mod_to   : &mem),
+		rsnd_mod_id  (mod_to   ? mod_to   : &mem));
+
+	ret = attach(io, dma, mod_from, mod_to);
+	if (ret < 0)
+		return ret;
+
+	dma->src_addr = rsnd_dma_addr(io, mod_from, is_play, 1);
+	dma->dst_addr = rsnd_dma_addr(io, mod_to,   is_play, 0);
+	dma->mod_from = mod_from;
+	dma->mod_to   = mod_to;
+
+	return 0;
+}
+
+int rsnd_dma_attach(struct rsnd_dai_stream *io, struct rsnd_mod *mod,
+		    struct rsnd_mod **dma_mod)
+{
+	if (!(*dma_mod)) {
+		int ret = rsnd_dma_alloc(io, mod, dma_mod);
+
+		if (ret < 0)
+			return ret;
+	}
+
+	return rsnd_dai_connect(*dma_mod, io, (*dma_mod)->type);
+}
+
+int rsnd_dma_probe(struct rsnd_priv *priv)
+{
+	struct platform_device *pdev = rsnd_priv_to_pdev(priv);
+	struct device *dev = rsnd_priv_to_dev(priv);
+	struct rsnd_dma_ctrl *dmac;
+	struct resource *res;
+
+	/*
+	 * for Gen1
+	 */
+	if (rsnd_is_gen1(priv))
+		return 0;
+
+	/*
+	 * for Gen2 or later
+	 */
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "audmapp");
+	dmac = devm_kzalloc(dev, sizeof(*dmac), GFP_KERNEL);
+	if (!dmac || !res) {
+		dev_err(dev, "dma allocate failed\n");
+		return 0; /* it will be PIO mode */
+	}
+
+	dmac->dmapp_num = 0;
+	dmac->base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(dmac->base))
+		return PTR_ERR(dmac->base);
+
+	priv->dma = dmac;
+
+	/* dummy mem mod for debug */
+	return rsnd_mod_init(NULL, &mem, &mem_ops, NULL, NULL, 0, 0);
+}