Re: [alsa-devel] [RFC v2 PATCH] ASoC: wm8904: add CCF support

Hello Bo,

Le 25/03/2014 10:56, Bo Shen a écrit :

Enable WM8904 to support common clock framework.

• Now it supports use SoC provided clock or external oscillator as MCLK.

Signed-off-by: Bo Shen voice.shen@atmel.com

Documentation/devicetree/bindings/sound/wm8904.txt | 48 ++++++++++++++++++++++ sound/soc/codecs/wm8904.c | 17 ++++++++ 2 files changed, 65 insertions(+) create mode 100644 Documentation/devicetree/bindings/sound/wm8904.txt

diff --git a/Documentation/devicetree/bindings/sound/wm8904.txt b/Documentation/devicetree/bindings/sound/wm8904.txt new file mode 100644 index 0000000..bcf4aa0 --- /dev/null +++ b/Documentation/devicetree/bindings/sound/wm8904.txt @@ -0,0 +1,48 @@ +WM8904 audio CODEC

+This device supports I2C only.

+Required properties:

• • compatible: "wlf,wm8904"
• • reg: the I2C address of the device.
• • clocks and clock-names: reference to
• <Documentation/devicetree/bindings/clock/clock-bindings.txt>

+Pins on the device (for linking into audio routes):

• • IN1L
• • IN1R
• • IN2L
• • IN2R
• • IN3L
• • IN3R
• • HPOUTL
• • HPOUTR
• • LINEOUTL
• • LINEOUTR
• • MICBIAS

+Examples:

+1. Using SoC provided clock as mclk: +codec: wm8904@1a {

• compatible = "wlf,wm8904";
• reg = <0x1a>;
• clocks = <&pck0>;
• clock-names = "mclk";

+};

+2. Using external oscillator as mclk: +codec: wm8904@1a {

• compatible = "wlf,wm8904";
• reg = <0x1a>;
• wm8904_osc {

• compatible = "fixed-clock";
  

• #clock-cells = <0>;
  

• #clock-frequency = <12000000>;
  

• }
• clocks = <&wm8904_osc>;
• clock-names = "mclk";

+};

I think there is a misunderstanding here (and it certainly comes from my explanations during our last talk :)): both cases should be handled the same way because an external oscillator is no more or less than an external clk (we don't care how this clk is generated).

I suggested to put the osc node inside the wm8904 one but I thought you were trying to represent the internal 12MHz clk generated when using the fll free running mode.

diff --git a/sound/soc/codecs/wm8904.c b/sound/soc/codecs/wm8904.c index 49c35c3..4db6a26 100644 --- a/sound/soc/codecs/wm8904.c +++ b/sound/soc/codecs/wm8904.c @@ -11,6 +11,7 @@

• published by the Free Software Foundation.

*/

+#include <linux/clk.h> #include <linux/module.h> #include <linux/moduleparam.h> #include <linux/init.h> @@ -49,6 +50,7 @@ static const char *wm8904_supply_names[WM8904_NUM_SUPPLIES] = { /* codec private data */ struct wm8904_priv { struct regmap *regmap;

• struct clk *mclk;

  enum wm8904_type devtype;

@@ -1828,6 +1830,9 @@ static int wm8904_set_bias_level(struct snd_soc_codec *codec,

switch (level) { case SND_SOC_BIAS_ON:

• if (IS_ENABLED(CONFIG_COMMON_CLK))
  

• 	if (wm8904->mclk)
  

• 		clk_prepare_enable(wm8904->mclk);
  

  break;

  case SND_SOC_BIAS_PREPARE:

@@ -1894,6 +1899,9 @@ static int wm8904_set_bias_level(struct snd_soc_codec *codec,

regulator_bulk_disable(ARRAY_SIZE(wm8904->supplies),
		       wm8904->supplies);

• if (IS_ENABLED(CONFIG_COMMON_CLK))
  

• 	if (wm8904->mclk)
  

• 		clk_disable_unprepare(wm8904->mclk);
  

  break; } codec->dapm.bias_level = level;

@@ -2139,6 +2147,15 @@ static int wm8904_i2c_probe(struct i2c_client *i2c, return ret; }

• if (IS_ENABLED(CONFIG_COMMON_CLK)) {

• wm8904->mclk = devm_clk_get(&i2c->dev, "mclk");
  

• if (IS_ERR(wm8904->mclk)) {
  

• 	dev_err(&i2c->dev, "Failed to get MCLK\n");
  

• 	ret = PTR_ERR(wm8904->mclk);
  

• 	goto err_enable;
  

• }
  

• }
• ret = regmap_read(wm8904->regmap, WM8904_SW_RESET_AND_ID, &val); if (ret < 0) { dev_err(&i2c->dev, "Failed to read ID register: %d\n", ret);