static void rsnd_dmaen_start(struct rsnd_dai_stream *io, struct rsnd_dma *dma)
{
	struct rsnd_dmaen *dmaen = rsnd_dma_to_dmaen(dma);
	struct rsnd_mod *mod = rsnd_dma_to_mod(dma);
	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
	struct snd_pcm_substream *substream = io->substream;
	struct device *dev = rsnd_priv_to_dev(priv);
	struct dma_async_tx_descriptor *desc;
	int is_play = rsnd_io_is_play(io);

	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;
	}

	desc->callback		= rsnd_dmaen_complete;
	desc->callback_param	= mod;

	if (dmaengine_submit(desc) < 0) {
		dev_err(dev, "dmaengine_submit() fail\n");
		return;
	}

	dma_async_issue_pending(dmaen->chan);
}

static int rsnd_src_probe_gen2(struct rsnd_mod *mod,
			       struct rsnd_dai *rdai,
			       struct rsnd_dai_stream *io)
{
	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
	struct rcar_snd_info *info = rsnd_priv_to_info(priv);
	struct rsnd_src *src = rsnd_mod_to_src(mod);
	struct rsnd_mod *ssi = rsnd_ssi_mod_get(priv, rsnd_mod_id(mod));
	struct device *dev = rsnd_priv_to_dev(priv);
	int ret;
	int is_play;

	if (info->dai_info)
		is_play = rsnd_info_is_playback(priv, src);
	else
		is_play = rsnd_ssi_is_play(ssi);

	ret = rsnd_dma_init(priv,
			    rsnd_mod_to_dma(mod),
			    is_play,
			    src->info->dma_id);
	if (ret < 0)
		dev_err(dev, "SRC DMA failed\n");

	return ret;
}

/*
 *		Audio DMAC
 */
static void __rsnd_dmaen_complete(struct rsnd_mod *mod,
				  struct rsnd_dai_stream *io)
{
	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
	bool elapsed = false;
	unsigned long flags;

	/*
	 * Renesas sound Gen1 needs 1 DMAC,
	 * Gen2 needs 2 DMAC.
	 * In Gen2 case, it are Audio-DMAC, and Audio-DMAC-peri-peri.
	 * But, Audio-DMAC-peri-peri doesn't have interrupt,
	 * and this driver is assuming that here.
	 *
	 * If Audio-DMAC-peri-peri has interrpt,
	 * rsnd_dai_pointer_update() will be called twice,
	 * ant it will breaks io->byte_pos
	 */
	spin_lock_irqsave(&priv->lock, flags);

	if (rsnd_io_is_working(io))
		elapsed = rsnd_dai_pointer_update(io, io->byte_per_period);

	spin_unlock_irqrestore(&priv->lock, flags);

	if (elapsed)
		rsnd_dai_period_elapsed(io);
}

static void rsnd_ssi_hw_start(struct rsnd_ssi *ssi,
			      struct rsnd_dai *rdai,
			      struct rsnd_dai_stream *io)
{
	struct rsnd_priv *priv = rsnd_mod_to_priv(&ssi->mod);
	struct device *dev = rsnd_priv_to_dev(priv);
	u32 cr;

	if (0 == ssi->usrcnt) {
		clk_enable(ssi->clk);

		if (rsnd_rdai_is_clk_master(rdai)) {
			if (rsnd_ssi_clk_from_parent(ssi))
				rsnd_ssi_hw_start(ssi->parent, rdai, io);
			else
				rsnd_ssi_master_clk_start(ssi, io);
		}
	}

	cr  =	ssi->cr_own	|
		ssi->cr_clk	|
		ssi->cr_etc	|
		EN;

	rsnd_mod_write(&ssi->mod, SSICR, cr);

	ssi->usrcnt++;

	dev_dbg(dev, "ssi%d hw started\n", rsnd_mod_id(&ssi->mod));
}

static int rsnd_src_remove_gen2(struct rsnd_mod *mod,
				struct rsnd_dai *rdai)
{
	rsnd_dma_quit(rsnd_mod_to_priv(mod), rsnd_mod_to_dma(mod));

	return 0;
}

static void rsnd_adg_set_ssi_clk(struct rsnd_mod *ssi_mod, u32 val)
{
	struct rsnd_priv *priv = rsnd_mod_to_priv(ssi_mod);
	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
	struct rsnd_mod *adg_mod = rsnd_mod_get(adg);
	int id = rsnd_mod_id(ssi_mod);
	int shift = (id % 4) * 8;
	u32 mask = 0xFF << shift;

	rsnd_mod_confirm_ssi(ssi_mod);

	val = val << shift;

	/*
	 * SSI 8 is not connected to ADG.
	 * it works with SSI 7
	 */
	if (id == 8)
		return;

	switch (id / 4) {
	case 0:
		rsnd_mod_bset(adg_mod, AUDIO_CLK_SEL0, mask, val);
		break;
	case 1:
		rsnd_mod_bset(adg_mod, AUDIO_CLK_SEL1, mask, val);
		break;
	case 2:
		rsnd_mod_bset(adg_mod, AUDIO_CLK_SEL2, mask, val);
		break;
	}
}

static int rsnd_ssi_dma_probe(struct rsnd_mod *mod,
			  struct rsnd_dai *rdai,
			  struct rsnd_dai_stream *io)
{
	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
	struct rsnd_ssi *ssi = rsnd_mod_to_ssi(mod);
	struct rcar_snd_info *info = rsnd_priv_to_info(priv);
	struct device *dev = rsnd_priv_to_dev(priv);
	int dma_id = ssi->info->dma_id;
	int is_play;
	int ret;

	if (info->dai_info)
		is_play = rsnd_info_is_playback(priv, ssi);
	else
		is_play = rsnd_ssi_is_play(&ssi->mod);

	ret = rsnd_dma_init(
		priv, rsnd_mod_to_dma(mod),
		is_play,
		dma_id);

	if (ret < 0)
		dev_err(dev, "SSI DMA failed\n");

	return ret;
}

void rsnd_dma_start(struct rsnd_dma *dma)
{
	struct rsnd_mod *mod = rsnd_dma_to_mod(dma);
	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
	struct rsnd_dai_stream *io = rsnd_mod_to_io(mod);
	struct snd_pcm_substream *substream = io->substream;
	struct device *dev = rsnd_priv_to_dev(priv);
	struct dma_async_tx_descriptor *desc;

	desc = dmaengine_prep_dma_cyclic(dma->chan,
					 (dma->addr) ? dma->addr :
					 substream->runtime->dma_addr,
					 snd_pcm_lib_buffer_bytes(substream),
					 snd_pcm_lib_period_bytes(substream),
					 dma->dir,
					 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);

	if (!desc) {
		dev_err(dev, "dmaengine_prep_slave_sg() fail\n");
		return;
	}

	desc->callback		= rsnd_dma_complete;
	desc->callback_param	= dma;

	if (dmaengine_submit(desc) < 0) {
		dev_err(dev, "dmaengine_submit() fail\n");
		return;
	}

	dma_async_issue_pending(dma->chan);
}

/*
 *		SSI PIO
 */
static void rsnd_ssi_parent_attach(struct rsnd_mod *mod,
				   struct rsnd_dai_stream *io)
{
	struct rsnd_dai *rdai = rsnd_io_to_rdai(io);
	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);

	if (!__rsnd_ssi_is_pin_sharing(mod))
		return;

	if (!rsnd_rdai_is_clk_master(rdai))
		return;

	switch (rsnd_mod_id(mod)) {
	case 1:
	case 2:
		rsnd_dai_connect(rsnd_ssi_mod_get(priv, 0), io, RSND_MOD_SSIP);
		break;
	case 4:
		rsnd_dai_connect(rsnd_ssi_mod_get(priv, 3), io, RSND_MOD_SSIP);
		break;
	case 8:
		rsnd_dai_connect(rsnd_ssi_mod_get(priv, 7), io, RSND_MOD_SSIP);
		break;
	}
}

static struct dma_chan *rsnd_dvc_dma_req(struct rsnd_dai_stream *io,
					 struct rsnd_mod *mod)
{
	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);

	return rsnd_dma_request_channel(rsnd_dvc_of_node(priv),
					mod, "tx");
}

static int rsnd_ssi_dma_remove(struct rsnd_mod *mod,
			       struct rsnd_dai *rdai,
			       struct rsnd_dai_stream *io)
{
	rsnd_dma_quit(rsnd_mod_to_priv(mod), rsnd_mod_to_dma(mod));

	return 0;
}

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 int rsnd_src_set_convert_timing_gen1(struct rsnd_mod *mod,
					    struct rsnd_dai *rdai,
					    struct rsnd_dai_stream *io)
{
	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
	struct rsnd_src *src = rsnd_mod_to_src(mod);
	struct snd_pcm_runtime *runtime = rsnd_io_to_runtime(io);
	u32 convert_rate = rsnd_src_convert_rate(src);
	u32 mask;
	u32 val;
	int shift;
	int id = rsnd_mod_id(mod);
	int ret;

	/*
	 * SRC_TIMING_SELECT
	 */
	shift	= (id % 4) * 8;
	mask	= 0x1F << shift;

	/*
	 * ADG is used as source clock if SRC was used,
	 * then, SSI WS is used as destination clock.
	 * SSI WS is used as source clock if SRC is not used
	 * (when playback, source/destination become reverse when capture)
	 */
	ret = 0;
	if (convert_rate) {
		/* use ADG */
		val = 0;
		ret = rsnd_adg_set_convert_clk_gen1(priv, mod,
						    runtime->rate,
						    convert_rate);
	} else if (8 == id) {
		/* use SSI WS, but SRU8 is special */
		val = id << shift;
	} else {
		/* use SSI WS */
		val = (id + 1) << shift;
	}

	if (ret < 0)
		return ret;

	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;
}

int rsnd_adg_ssi_clk_try_start(struct rsnd_mod *mod, unsigned int rate)
{
	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
	struct device *dev = rsnd_priv_to_dev(priv);
	struct clk *clk;
	int i;
	u32 data;
	int sel_table[] = {
		[CLKA] = 0x1,
		[CLKB] = 0x2,
		[CLKC] = 0x3,
		[CLKI] = 0x0,
	};

	dev_dbg(dev, "request clock = %d\n", rate);

	/*
	 * find suitable clock from
	 * AUDIO_CLKA/AUDIO_CLKB/AUDIO_CLKC/AUDIO_CLKI.
	 */
	data = 0;
	for_each_rsnd_clk(clk, adg, i) {
		if (rate == clk_get_rate(clk)) {
			data = sel_table[i];
			goto found_clock;
		}
	}

	/*
	 * find divided clock from BRGA/BRGB
	 */
	if (rate  == adg->rbga_rate_for_441khz) {
		data = 0x10;
		goto found_clock;
	}

	if (rate == adg->rbgb_rate_for_48khz) {
		data = 0x20;
		goto found_clock;
	}

	return -EIO;

found_clock:

	/*
	 * This "mod" = "ssi" here.
	 * we can get "ssi id" from mod
	 */
	rsnd_adg_set_ssi_clk(mod, data);

	dev_dbg(dev, "ADG: %s[%d] selects 0x%x for %d\n",
		rsnd_mod_name(mod), rsnd_mod_id(mod),
		data, rate);

	return 0;
}

/*
 *	SSI mod common functions
 */
static int rsnd_ssi_init(struct rsnd_mod *mod,
			 struct rsnd_dai *rdai,
			 struct rsnd_dai_stream *io)
{
	struct rsnd_ssi *ssi = rsnd_mod_to_ssi(mod);
	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
	struct device *dev = rsnd_priv_to_dev(priv);
	struct snd_pcm_runtime *runtime = rsnd_io_to_runtime(io);
	u32 cr;

	cr = FORCE;

	/*
	 * always use 32bit system word for easy clock calculation.
	 * see also rsnd_ssi_master_clk_enable()
	 */
	cr |= SWL_32;

	/*
	 * init clock settings for SSICR
	 */
	switch (runtime->sample_bits) {
	case 16:
		cr |= DWL_16;
		break;
	case 32:
		cr |= DWL_24;
		break;
	default:
		return -EIO;
	}

	if (rdai->bit_clk_inv)
		cr |= SCKP;
	if (rdai->frm_clk_inv)
		cr |= SWSP;
	if (rdai->data_alignment)
		cr |= SDTA;
	if (rdai->sys_delay)
		cr |= DEL;
	if (rsnd_dai_is_play(rdai, io))
		cr |= TRMD;

	/*
	 * set ssi parameter
	 */
	ssi->rdai	= rdai;
	ssi->io		= io;
	ssi->cr_own	= cr;
	ssi->err	= -1; /* ignore 1st error */

	rsnd_ssi_mode_set(priv, rdai, ssi);

	dev_dbg(dev, "%s.%d init\n", rsnd_mod_name(mod), rsnd_mod_id(mod));

	return 0;
}

static int rsnd_src_probe_gen1(struct rsnd_mod *mod,
			      struct rsnd_dai *rdai)
{
	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
	struct device *dev = rsnd_priv_to_dev(priv);

	dev_dbg(dev, "%s (Gen1) is probed\n", rsnd_mod_name(mod));

	return 0;
}

void rsnd_mod_make_sure(struct rsnd_mod *mod, enum rsnd_mod_type type)
{
	if (mod->type != type) {
		struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
		struct device *dev = rsnd_priv_to_dev(priv);

		dev_warn(dev, "%s[%d] is not your expected module\n",
			 rsnd_mod_name(mod), rsnd_mod_id(mod));
	}
}

void rsnd_dma_quit(struct rsnd_dai_stream *io, struct rsnd_dma *dma)
{
	struct rsnd_mod *mod = rsnd_dma_to_mod(dma);
	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
	struct rsnd_dma_ctrl *dmac = rsnd_priv_to_dmac(priv);

	if (!dmac)
		return;

	dma->ops->quit(io, dma);
}

/*
 *		Non SSI
 */
static int rsnd_ssi_non(struct rsnd_mod *mod,
			struct rsnd_dai *rdai,
			struct rsnd_dai_stream *io)
{
	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
	struct device *dev = rsnd_priv_to_dev(priv);

	dev_dbg(dev, "%s\n", __func__);

	return 0;
}

int rsnd_src_enable_ssi_irq(struct rsnd_mod *ssi_mod,
			    struct rsnd_dai *rdai)
{
	struct rsnd_priv *priv = rsnd_mod_to_priv(ssi_mod);

	/* enable PIO interrupt if Gen2 */
	if (rsnd_is_gen2(priv))
		rsnd_mod_write(ssi_mod, INT_ENABLE, 0x0f000000);

	return 0;
}