ASoC: samsung: odroid: Drop requirement of clocks in the sound node

As suggested in reviews the requirement of clocks in the 'sound' node
is dropped and instead a leaf clock is used to configure frequency
of the audio root clock PLL. This can work now after the clock tree
definitions have been updated to allow clock rate setting propagation
on the path from the I2S controller up to the EPLL.

This patch also lowers the CODEC master clock frequency so as
to not exceed the maximum allowed 60 MHz at maximum audio sampling
rates.
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/samsung,odroid.txt

@@ -7,9 +7,6 @@ Required properties:
  - model - the user-visible name of this sound complex
  - clocks - should contain entries matching clock names in the clock-names
     property
- - clock-names - should contain following entries:
-    - "epll" - indicating the EPLL output clock
-    - "i2s_rclk" - indicating the RCLK (root) clock of the I2S0 controller
  - samsung,audio-widgets - this property specifies off-codec audio elements
    like headphones or speakers, for details see widgets.txt
  - samsung,audio-routing - a list of the connections between audio
@@ -46,9 +43,6 @@ sound {
 		"IN1", "Mic Jack",
 		"Mic Jack", "MICBIAS";
 
-	clocks = <&clock CLK_FOUT_EPLL>, <&i2s0 CLK_I2S_RCLK_SRC>;
-	clock-names = "epll", "sclk_i2s";
-
 	cpu {
 		sound-dai = <&i2s0 0>;
 	};

sound/soc/samsung/odroid.c

@@ -19,8 +19,8 @@ struct odroid_priv {
 	struct snd_soc_card card;
 	struct snd_soc_dai_link dai_link;
 
-	struct clk *pll;
-	struct clk *rclk;
+	struct clk *clk_i2s_bus;
+	struct clk *sclk_i2s;
 };
 
 static int odroid_card_startup(struct snd_pcm_substream *substream)
@@ -58,13 +58,18 @@ static int odroid_card_hw_params(struct snd_pcm_substream *substream,
 		return -EINVAL;
 	}
 
-	ret = clk_set_rate(priv->pll, pll_freq + 1);
+	ret = clk_set_rate(priv->clk_i2s_bus, pll_freq / 2 + 1);
 	if (ret < 0)
 		return ret;
 
-	rclk_freq = params_rate(params) * 256 * 4;
+	/*
+	 *  We add 1 to the rclk_freq value in order to avoid too low clock
+	 *  frequency values due to the EPLL output frequency not being exact
+	 *  multiple of the audio sampling rate.
+	 */
+	rclk_freq = params_rate(params) * 256 + 1;
 
-	ret = clk_set_rate(priv->rclk, rclk_freq);
+	ret = clk_set_rate(priv->sclk_i2s, rclk_freq);
 	if (ret < 0)
 		return ret;
 
@@ -118,14 +123,6 @@ static int odroid_audio_probe(struct platform_device *pdev)
 
 	snd_soc_card_set_drvdata(card, priv);
 
-	priv->pll = devm_clk_get(dev, "epll");
-	if (IS_ERR(priv->pll))
-		return PTR_ERR(priv->pll);
-
-	priv->rclk = devm_clk_get(dev, "i2s_rclk");
-	if (IS_ERR(priv->rclk))
-		return PTR_ERR(priv->rclk);
-
 	ret = snd_soc_of_parse_card_name(card, "model");
 	if (ret < 0)
 		return ret;
@@ -171,14 +168,31 @@ static int odroid_audio_probe(struct platform_device *pdev)
 	link->name = "Primary";
 	link->stream_name = link->name;
 
+
+	priv->sclk_i2s = of_clk_get_by_name(link->cpu_of_node, "i2s_opclk1");
+	if (IS_ERR(priv->sclk_i2s)) {
+		ret = PTR_ERR(priv->sclk_i2s);
+		goto err_put_i2s_n;
+	}
+
+	priv->clk_i2s_bus = of_clk_get_by_name(link->cpu_of_node, "iis");
+	if (IS_ERR(priv->clk_i2s_bus)) {
+		ret = PTR_ERR(priv->clk_i2s_bus);
+		goto err_put_sclk;
+	}
+
 	ret = devm_snd_soc_register_card(dev, card);
 	if (ret < 0) {
 		dev_err(dev, "snd_soc_register_card() failed: %d\n", ret);
-		goto err_put_i2s_n;
+		goto err_put_clk_i2s;
 	}
 
 	return 0;
 
+err_put_clk_i2s:
+	clk_put(priv->clk_i2s_bus);
+err_put_sclk:
+	clk_put(priv->sclk_i2s);
 err_put_i2s_n:
 	of_node_put(link->cpu_of_node);
 err_put_codec_n:
@@ -192,6 +206,8 @@ static int odroid_audio_remove(struct platform_device *pdev)
 
 	of_node_put(priv->dai_link.cpu_of_node);
 	odroid_put_codec_of_nodes(&priv->dai_link);
+	clk_put(priv->sclk_i2s);
+	clk_put(priv->clk_i2s_bus);
 
 	return 0;
 }