ASoC: rsnd: add rsnd_adg_clk_query()

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, it needs SSI clock query feature, and it needs
ADG clock query feature. Current ADG has rsnd_adg_ssi_clk_try_start()
and it is doing similar things, but it try to setup ADG register in
same time. This is not needed.

This patch adds new rsnd_adg_clk_query() and separates query feature
and register setting feature in adg.c

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/adg.c

@@ -308,23 +308,12 @@ static void rsnd_adg_set_ssi_clk(struct rsnd_mod *ssi_mod, u32 val)
 	}
 }
 
-int rsnd_adg_ssi_clk_stop(struct rsnd_mod *ssi_mod)
-{
-	rsnd_adg_set_ssi_clk(ssi_mod, 0);
-
-	return 0;
-}
-
-int rsnd_adg_ssi_clk_try_start(struct rsnd_mod *ssi_mod, unsigned int rate)
+int rsnd_adg_clk_query(struct rsnd_priv *priv, unsigned int rate)
 {
-	struct rsnd_priv *priv = rsnd_mod_to_priv(ssi_mod);
 	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
 	struct device *dev = rsnd_priv_to_dev(priv);
-	struct rsnd_mod *adg_mod = rsnd_mod_get(adg);
 	struct clk *clk;
 	int i;
-	u32 data;
-	u32 ckr = 0;
 	int sel_table[] = {
 		[CLKA] = 0x1,
 		[CLKB] = 0x2,
@@ -338,30 +327,42 @@ int rsnd_adg_ssi_clk_try_start(struct rsnd_mod *ssi_mod, unsigned int 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;
-		}
+		if (rate == clk_get_rate(clk))
+			return sel_table[i];
 	}
 
 	/*
 	 * find divided clock from BRGA/BRGB
 	 */
-	if (rate  == adg->rbga_rate_for_441khz) {
-		data = 0x10;
-		goto found_clock;
-	}
+	if (rate == adg->rbga_rate_for_441khz)
+		return 0x10;
 
-	if (rate == adg->rbgb_rate_for_48khz) {
-		data = 0x20;
-		goto found_clock;
-	}
+	if (rate == adg->rbgb_rate_for_48khz)
+		return 0x20;
 
 	return -EIO;
+}
+
+int rsnd_adg_ssi_clk_stop(struct rsnd_mod *ssi_mod)
+{
+	rsnd_adg_set_ssi_clk(ssi_mod, 0);
+
+	return 0;
+}
+
+int rsnd_adg_ssi_clk_try_start(struct rsnd_mod *ssi_mod, unsigned int rate)
+{
+	struct rsnd_priv *priv = rsnd_mod_to_priv(ssi_mod);
+	struct rsnd_adg *adg = rsnd_priv_to_adg(priv);
+	struct device *dev = rsnd_priv_to_dev(priv);
+	struct rsnd_mod *adg_mod = rsnd_mod_get(adg);
+	int data;
+	u32 ckr = 0;
 
-found_clock:
+	data = rsnd_adg_clk_query(priv, rate);
+	if (data < 0)
+		return data;
 
 	rsnd_adg_set_ssi_clk(ssi_mod, data);
 

sound/soc/sh/rcar/rsnd.h

@@ -502,6 +502,7 @@ phys_addr_t rsnd_gen_get_phy_addr(struct rsnd_priv *priv, int reg_id);
 /*
  *	R-Car ADG
  */
+int rsnd_adg_clk_query(struct rsnd_priv *priv, unsigned int rate);
 int rsnd_adg_ssi_clk_stop(struct rsnd_mod *mod);
 int rsnd_adg_ssi_clk_try_start(struct rsnd_mod *mod, unsigned int rate);
 int rsnd_adg_probe(struct rsnd_priv *priv);