ASRC can be used on memory to memory case, define several
functions for m2m usage and export them as function pointer.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Acked-by: Jaroslav Kysela <perex@perex.cz>
---
 sound/soc/fsl/fsl_easrc.c | 228 ++++++++++++++++++++++++++++++++++++++
 sound/soc/fsl/fsl_easrc.h |   4 +
 2 files changed, 232 insertions(+)

diff --git a/sound/soc/fsl/fsl_easrc.c b/sound/soc/fsl/fsl_easrc.c
index d22f0621c465..f17a185a1910 100644
--- a/sound/soc/fsl/fsl_easrc.c
+++ b/sound/soc/fsl/fsl_easrc.c
@@ -1861,6 +1861,224 @@ static int fsl_easrc_get_fifo_addr(u8 dir, enum asrc_pair_index index)
 	return REG_EASRC_FIFO(dir, index);
 }
 
+/* Get sample numbers in FIFO */
+static unsigned int fsl_easrc_get_output_fifo_size(struct fsl_asrc_pair *pair)
+{
+	struct fsl_asrc *asrc = pair->asrc;
+	enum asrc_pair_index index = pair->index;
+	u32 val;
+
+	regmap_read(asrc->regmap, REG_EASRC_SFS(index), &val);
+	val &= EASRC_SFS_NSGO_MASK;
+
+	return val >> EASRC_SFS_NSGO_SHIFT;
+}
+
+static int fsl_easrc_m2m_prepare(struct fsl_asrc_pair *pair)
+{
+	struct fsl_easrc_ctx_priv *ctx_priv = pair->private;
+	struct fsl_asrc *asrc = pair->asrc;
+	struct device *dev = &asrc->pdev->dev;
+	int ret;
+
+	ctx_priv->in_params.sample_rate = pair->rate[IN];
+	ctx_priv->in_params.sample_format = pair->sample_format[IN];
+	ctx_priv->out_params.sample_rate = pair->rate[OUT];
+	ctx_priv->out_params.sample_format = pair->sample_format[OUT];
+
+	ctx_priv->in_params.fifo_wtmk = FSL_EASRC_INPUTFIFO_WML;
+	ctx_priv->out_params.fifo_wtmk = FSL_EASRC_OUTPUTFIFO_WML;
+	/* Fill the right half of the re-sampler with zeros */
+	ctx_priv->rs_init_mode = 0x2;
+	/* Zero fill the right half of the prefilter */
+	ctx_priv->pf_init_mode = 0x2;
+
+	ret = fsl_easrc_set_ctx_format(pair,
+				       &ctx_priv->in_params.sample_format,
+				       &ctx_priv->out_params.sample_format);
+	if (ret) {
+		dev_err(dev, "failed to set context format: %d\n", ret);
+		return ret;
+	}
+
+	ret = fsl_easrc_config_context(asrc, pair->index);
+	if (ret) {
+		dev_err(dev, "failed to config context %d\n", ret);
+		return ret;
+	}
+
+	ctx_priv->in_params.iterations = 1;
+	ctx_priv->in_params.group_len = pair->channels;
+	ctx_priv->in_params.access_len = pair->channels;
+	ctx_priv->out_params.iterations = 1;
+	ctx_priv->out_params.group_len = pair->channels;
+	ctx_priv->out_params.access_len = pair->channels;
+
+	ret = fsl_easrc_set_ctx_organziation(pair);
+	if (ret) {
+		dev_err(dev, "failed to set fifo organization\n");
+		return ret;
+	}
+
+	/* The context start flag */
+	pair->first_convert = 1;
+	return 0;
+}
+
+static int fsl_easrc_m2m_start(struct fsl_asrc_pair *pair)
+{
+	/* start context once */
+	if (pair->first_convert) {
+		fsl_easrc_start_context(pair);
+		pair->first_convert = 0;
+	}
+
+	return 0;
+}
+
+static int fsl_easrc_m2m_stop(struct fsl_asrc_pair *pair)
+{
+	/* Stop pair/context */
+	if (!pair->first_convert) {
+		fsl_easrc_stop_context(pair);
+		pair->first_convert = 1;
+	}
+
+	return 0;
+}
+
+/* calculate capture data length according to output data length and sample rate */
+static int fsl_easrc_m2m_calc_out_len(struct fsl_asrc_pair *pair, int input_buffer_length)
+{
+	struct fsl_asrc *easrc = pair->asrc;
+	struct fsl_easrc_priv *easrc_priv = easrc->private;
+	struct fsl_easrc_ctx_priv *ctx_priv = pair->private;
+	unsigned int in_rate = ctx_priv->in_params.norm_rate;
+	unsigned int out_rate = ctx_priv->out_params.norm_rate;
+	unsigned int channels = pair->channels;
+	unsigned int in_samples, out_samples;
+	unsigned int in_width, out_width;
+	unsigned int out_length;
+	unsigned int frac_bits;
+	u64 val1, val2;
+
+	switch (easrc_priv->rs_num_taps) {
+	case EASRC_RS_32_TAPS:
+		/* integer bits = 5; */
+		frac_bits = 39;
+		break;
+	case EASRC_RS_64_TAPS:
+		/* integer bits = 6; */
+		frac_bits = 38;
+		break;
+	case EASRC_RS_128_TAPS:
+		/* integer bits = 7; */
+		frac_bits = 37;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	val1 = (u64)in_rate << frac_bits;
+	do_div(val1, out_rate);
+	val1 += (s64)ctx_priv->ratio_mod << (frac_bits - 31);
+
+	in_width = snd_pcm_format_physical_width(ctx_priv->in_params.sample_format) / 8;
+	out_width = snd_pcm_format_physical_width(ctx_priv->out_params.sample_format) / 8;
+
+	ctx_priv->in_filled_len += input_buffer_length;
+	if (ctx_priv->in_filled_len <= ctx_priv->in_filled_sample * in_width * channels) {
+		out_length = 0;
+	} else {
+		in_samples = ctx_priv->in_filled_len / (in_width * channels) -
+			     ctx_priv->in_filled_sample;
+
+		/* right shift 12 bit to make ratio in 32bit space */
+		val2 = (u64)in_samples << (frac_bits - 12);
+		val1 = val1 >> 12;
+		do_div(val2, val1);
+		out_samples = val2;
+
+		out_length = out_samples * out_width * channels;
+		ctx_priv->in_filled_len = ctx_priv->in_filled_sample * in_width * channels;
+	}
+
+	return out_length;
+}
+
+static int fsl_easrc_m2m_get_maxburst(u8 dir, struct fsl_asrc_pair *pair)
+{
+	struct fsl_easrc_ctx_priv *ctx_priv = pair->private;
+
+	if (dir == IN)
+		return ctx_priv->in_params.fifo_wtmk * pair->channels;
+	else
+		return ctx_priv->out_params.fifo_wtmk * pair->channels;
+}
+
+static int fsl_easrc_m2m_pair_suspend(struct fsl_asrc_pair *pair)
+{
+	fsl_easrc_stop_context(pair);
+
+	return 0;
+}
+
+static int fsl_easrc_m2m_pair_resume(struct fsl_asrc_pair *pair)
+{
+	struct fsl_easrc_ctx_priv *ctx_priv = pair->private;
+
+	pair->first_convert = 1;
+	ctx_priv->in_filled_len = 0;
+
+	return 0;
+}
+
+/* val is Q31 */
+static int fsl_easrc_m2m_set_ratio_mod(struct fsl_asrc_pair *pair, int val)
+{
+	struct fsl_easrc_ctx_priv *ctx_priv = pair->private;
+	struct fsl_asrc *easrc = pair->asrc;
+	struct fsl_easrc_priv *easrc_priv = easrc->private;
+	unsigned int frac_bits;
+
+	ctx_priv->ratio_mod += val;
+
+	switch (easrc_priv->rs_num_taps) {
+	case EASRC_RS_32_TAPS:
+		/* integer bits = 5; */
+		frac_bits = 39;
+		break;
+	case EASRC_RS_64_TAPS:
+		/* integer bits = 6; */
+		frac_bits = 38;
+		break;
+	case EASRC_RS_128_TAPS:
+		/* integer bits = 7; */
+		frac_bits = 37;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	val <<= (frac_bits - 31);
+	regmap_write(easrc->regmap, REG_EASRC_RUC(pair->index), EASRC_RSUC_RS_RM(val));
+
+	return 0;
+}
+
+static int fsl_easrc_m2m_get_cap(struct fsl_asrc_m2m_cap *cap)
+{
+	cap->fmt_in = FSL_EASRC_FORMATS;
+	cap->fmt_out = FSL_EASRC_FORMATS | SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE;
+	cap->rate_in = easrc_rates;
+	cap->rate_in_count = ARRAY_SIZE(easrc_rates);
+	cap->rate_out = easrc_rates;
+	cap->rate_out_count = ARRAY_SIZE(easrc_rates);
+	cap->chan_min = 1;
+	cap->chan_max = 32;
+	return 0;
+}
+
 static const struct of_device_id fsl_easrc_dt_ids[] = {
 	{ .compatible = "fsl,imx8mn-easrc",},
 	{}
@@ -1926,6 +2144,16 @@ static int fsl_easrc_probe(struct platform_device *pdev)
 	easrc->release_pair = fsl_easrc_release_context;
 	easrc->get_fifo_addr = fsl_easrc_get_fifo_addr;
 	easrc->pair_priv_size = sizeof(struct fsl_easrc_ctx_priv);
+	easrc->m2m_prepare = fsl_easrc_m2m_prepare;
+	easrc->m2m_start = fsl_easrc_m2m_start;
+	easrc->m2m_stop = fsl_easrc_m2m_stop;
+	easrc->get_output_fifo_size = fsl_easrc_get_output_fifo_size;
+	easrc->m2m_calc_out_len = fsl_easrc_m2m_calc_out_len;
+	easrc->m2m_get_maxburst = fsl_easrc_m2m_get_maxburst;
+	easrc->m2m_pair_suspend = fsl_easrc_m2m_pair_suspend;
+	easrc->m2m_pair_resume = fsl_easrc_m2m_pair_resume;
+	easrc->m2m_set_ratio_mod = fsl_easrc_m2m_set_ratio_mod;
+	easrc->m2m_get_cap = fsl_easrc_m2m_get_cap;
 
 	easrc_priv->rs_num_taps = EASRC_RS_32_TAPS;
 	easrc_priv->const_coeff = 0x3FF0000000000000;
diff --git a/sound/soc/fsl/fsl_easrc.h b/sound/soc/fsl/fsl_easrc.h
index 7c70dac52713..c9f770862662 100644
--- a/sound/soc/fsl/fsl_easrc.h
+++ b/sound/soc/fsl/fsl_easrc.h
@@ -601,6 +601,8 @@ struct fsl_easrc_slot {
  * @out_missed_sample: sample missed in output
  * @st1_addexp: exponent added for stage1
  * @st2_addexp: exponent added for stage2
+ * @ratio_mod: update ratio
+ * @in_filled_len: input filled length
  */
 struct fsl_easrc_ctx_priv {
 	struct fsl_easrc_io_params in_params;
@@ -618,6 +620,8 @@ struct fsl_easrc_ctx_priv {
 	int out_missed_sample;
 	int st1_addexp;
 	int st2_addexp;
+	int ratio_mod;
+	unsigned int in_filled_len;
 };
 
 /**
-- 
2.34.1