ASoC: rsnd: add rsnd_soc_hw_rule/constraint()

Current Renesas sound driver is assuming that all Sampling rate and
channles are possible to use, but these are depends on inputed clock
and SSI connection situation.
For example, if it is using 1 SSI, enabled TDM mode and has 12288000
input clock, 2ch output can support until 192000Hz, but 6ch output can
support until 64000Hz, 8ch can support 48000Hz.
To control these situation correctly, it needs to support
hw_constraints / refine feature.

To support such feature, this patch adds new
rsnd_soc_hw_rule/constraint() which adds hw rule of Channel and
Sampling Rate.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Tested-by: Hiroyuki Yokoyama <hiroyuki.yokoyama.vx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sh/rcar/core.c

@@ -723,7 +723,10 @@ static int rsnd_soc_set_dai_tdm_slot(struct snd_soc_dai *dai,
 	struct device *dev = rsnd_priv_to_dev(priv);
 
 	switch (slots) {
+	case 2:
 	case 6:
+	case 8:
+	case 16:
 		/* TDM Extend Mode */
 		rsnd_rdai_channels_set(rdai, slots);
 		rsnd_rdai_ssi_lane_set(rdai, 1);
@@ -736,6 +739,151 @@ static int rsnd_soc_set_dai_tdm_slot(struct snd_soc_dai *dai,
 	return 0;
 }
 
+static unsigned int rsnd_soc_hw_channels_list[] = {
+	2, 6, 8, 16,
+};
+
+static unsigned int rsnd_soc_hw_rate_list[] = {
+	  8000,
+	 11025,
+	 16000,
+	 22050,
+	 32000,
+	 44100,
+	 48000,
+	 64000,
+	 88200,
+	 96000,
+	176400,
+	192000,
+};
+
+static int rsnd_soc_hw_rule(struct rsnd_priv *priv,
+			    unsigned int *list, int list_num,
+			    struct snd_interval *baseline, struct snd_interval *iv)
+{
+	struct snd_interval p;
+	int rate;
+	int i;
+
+	snd_interval_any(&p);
+	p.min = UINT_MAX;
+	p.max = 0;
+
+	for (i = 0; i < list_num; i++) {
+
+		if (!snd_interval_test(iv, list[i]))
+			continue;
+
+		rate = rsnd_ssi_clk_query(priv,
+					  baseline->min, list[i], NULL);
+		if (rate > 0) {
+			p.min = min(p.min, list[i]);
+			p.max = max(p.max, list[i]);
+		}
+
+		rate = rsnd_ssi_clk_query(priv,
+					  baseline->max, list[i], NULL);
+		if (rate > 0) {
+			p.min = min(p.min, list[i]);
+			p.max = max(p.max, list[i]);
+		}
+	}
+
+	return snd_interval_refine(iv, &p);
+}
+
+static int rsnd_soc_hw_rule_rate(struct snd_pcm_hw_params *params,
+				 struct snd_pcm_hw_rule *rule)
+{
+	struct snd_interval *ic_ = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
+	struct snd_interval *ir = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
+	struct snd_interval ic;
+	struct snd_soc_dai *dai = rule->private;
+	struct rsnd_dai *rdai = rsnd_dai_to_rdai(dai);
+	struct rsnd_priv *priv = rsnd_rdai_to_priv(rdai);
+
+	/*
+	 * possible sampling rate limitation is same as
+	 * 2ch if it supports multi ssi
+	 */
+	ic = *ic_;
+	if (1 < rsnd_rdai_ssi_lane_get(rdai)) {
+		ic.min = 2;
+		ic.max = 2;
+	}
+
+	return rsnd_soc_hw_rule(priv, rsnd_soc_hw_rate_list,
+				ARRAY_SIZE(rsnd_soc_hw_rate_list),
+				&ic, ir);
+}
+
+
+static int rsnd_soc_hw_rule_channels(struct snd_pcm_hw_params *params,
+				     struct snd_pcm_hw_rule *rule)
+{
+	struct snd_interval *ic_ = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
+	struct snd_interval *ir = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
+	struct snd_interval ic;
+	struct snd_soc_dai *dai = rule->private;
+	struct rsnd_dai *rdai = rsnd_dai_to_rdai(dai);
+	struct rsnd_priv *priv = rsnd_rdai_to_priv(rdai);
+
+	/*
+	 * possible sampling rate limitation is same as
+	 * 2ch if it supports multi ssi
+	 */
+	ic = *ic_;
+	if (1 < rsnd_rdai_ssi_lane_get(rdai)) {
+		ic.min = 2;
+		ic.max = 2;
+	}
+
+	return rsnd_soc_hw_rule(priv, rsnd_soc_hw_channels_list,
+				ARRAY_SIZE(rsnd_soc_hw_channels_list),
+				ir, &ic);
+}
+
+static void rsnd_soc_hw_constraint(struct snd_pcm_runtime *runtime,
+				   struct snd_soc_dai *dai)
+{
+	struct rsnd_dai *rdai = rsnd_dai_to_rdai(dai);
+	struct snd_pcm_hw_constraint_list *constraint = &rdai->constraint;
+	unsigned int max_channels = rsnd_rdai_channels_get(rdai);
+	int i;
+
+	/*
+	 * Channel Limitation
+	 * It depends on Platform design
+	 */
+	constraint->list	= rsnd_soc_hw_channels_list;
+	constraint->count	= 0;
+	constraint->mask	= 0;
+
+	for (i = 0; i < ARRAY_SIZE(rsnd_soc_hw_channels_list); i++) {
+		if (rsnd_soc_hw_channels_list[i] > max_channels)
+			break;
+		constraint->count = i + 1;
+	}
+
+	snd_pcm_hw_constraint_list(runtime, 0,
+				   SNDRV_PCM_HW_PARAM_CHANNELS, constraint);
+
+	/*
+	 * Sampling Rate / Channel Limitation
+	 * It depends on Clock Master Mode
+	 */
+	if (!rsnd_rdai_is_clk_master(rdai))
+		return;
+
+	snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
+			    rsnd_soc_hw_rule_rate, dai,
+			    SNDRV_PCM_HW_PARAM_CHANNELS, -1);
+	snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
+			    rsnd_soc_hw_rule_channels, dai,
+			    SNDRV_PCM_HW_PARAM_RATE, -1);
+}
+
 static int rsnd_soc_dai_startup(struct snd_pcm_substream *substream,
 				struct snd_soc_dai *dai)
 {
@@ -744,6 +892,9 @@ static int rsnd_soc_dai_startup(struct snd_pcm_substream *substream,
 	struct rsnd_dai_stream *io = rsnd_rdai_to_io(rdai, substream);
 	int ret;
 
+	/* rsnd_io_to_runtime() is not yet enabled here */
+	rsnd_soc_hw_constraint(substream->runtime, dai);
+
 	/*
 	 * call rsnd_dai_call without spinlock
 	 */
@@ -866,7 +1017,7 @@ static void __rsnd_dai_probe(struct rsnd_priv *priv,
 	drv->playback.rates		= RSND_RATES;
 	drv->playback.formats		= RSND_FMTS;
 	drv->playback.channels_min	= 2;
-	drv->playback.channels_max	= 6;
+	drv->playback.channels_max	= 16;
 	drv->playback.stream_name	= rdai->playback.name;
 
 	snprintf(rdai->capture.name, RSND_DAI_NAME_SIZE,
@@ -874,7 +1025,7 @@ static void __rsnd_dai_probe(struct rsnd_priv *priv,
 	drv->capture.rates		= RSND_RATES;
 	drv->capture.formats		= RSND_FMTS;
 	drv->capture.channels_min	= 2;
-	drv->capture.channels_max	= 6;
+	drv->capture.channels_max	= 16;
 	drv->capture.stream_name	= rdai->capture.name;
 
 	rdai->playback.rdai		= rdai;

sound/soc/sh/rcar/rsnd.h

@@ -449,6 +449,7 @@ struct rsnd_dai {
 	struct rsnd_dai_stream playback;
 	struct rsnd_dai_stream capture;
 	struct rsnd_priv *priv;
+	struct snd_pcm_hw_constraint_list constraint;
 
 	int max_channels;	/* 2ch - 16ch */
 	int ssi_lane;		/* 1lane - 4lane */