[RFC PATCH] ASoC: wm8904: add CCF support

Bo Shen
2014-03-21T02:51:02Z

Enable WM8904 to support common clock framework.
And also supports different clk configuration.

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

Documentation/devicetree/bindings/sound/wm8904.txt | 57 ++++++++++++++++++++++
sound/soc/codecs/wm8904.c | 39 +++++++++++++++
2 files changed, 96 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..039374d
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/wm8904.txt
@@ -0,0 +1,57 @@
+WM8904 audio CODEC
+
+This device supports I2C only.
+
+Required properties:
+ - compatible: "wlf,wm8904"
+ - reg: the I2C address of the device.
+
+ if work with CCF, the following properties as required:
+ - wlf,sysclk-from-mclk: set the sys clock is driven from mclk,
+ - wlf,mclk-use-xtal: if the mclk is generated by crystal.
+ if without this property, the mclk is generated from SOC.
+ - clocks: which clock generated clock to mclk.
+ - clock-names: the clock names use for retrieve.
+ - wlf,mclk-freq: mclk's frequency
+
+
+Pins on the device (for linking into audio routes):
+
+ * IN1L
+ * IN1R
+ * IN2L
+ * IN2R
+ * IN3L
+ * IN3R
+ * HPOUTL
+ * HPOUTR
+ * LINEOUTL
+ * LINEOUTR
+ * MICBIAS
+
+Examples:
+
+1. General usage:
+codec: wm8904@1a {
+ compatible = "wlf,wm8904";
+ reg = <0x1a>;
+};
+
+2. Working with CCF supports and using crystall provide mclk:
+codec: wm8904@1a {
+ compatible = "wlf,wm8904";
+ reg = <0x1a>;
+ wlf,sysclk-from-mclk;
+ wlf,mclk-use-xtal;
+ wlf,mclk-freq = <12000000>;
+};
+
+3. Working with CCF supports and using SoC provide mclk:
+codec: wm8904@1a {
+ compatible = "wlf,wm8904";
+ reg = <0x1a>;
+ wlf,sysclk-from-mclk;
+ clocks = <&pck0>;
+ clock-names = "mclk";
+ wlf,mclk-freq = <32768>;
+};
diff --git a/sound/soc/codecs/wm8904.c b/sound/soc/codecs/wm8904.c
index 49c35c3..99e3e90 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 +50,10 @@ static const char *wm8904_supply_names[WM8904_NUM_SUPPLIES] = {
/* codec private data */
struct wm8904_priv {
struct regmap *regmap;
+ struct clk *mclk;
+ bool sysclk_from_mclk;
+ bool mclk_use_xtal;
+ u32 mclk_freq;

enum wm8904_type devtype;

@@ -1828,6 +1833,9 @@ 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_use_xtal)
+ clk_prepare_enable(wm8904->mclk);
break;

case SND_SOC_BIAS_PREPARE:
@@ -1894,6 +1902,9 @@ 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_use_xtal)
+ clk_disable_unprepare(wm8904->mclk);
break;
}
codec->dapm.bias_level = level;
@@ -2139,6 +2150,34 @@ static int wm8904_i2c_probe(struct i2c_client *i2c,
return ret;
}

+ if (IS_ENABLED(CONFIG_COMMON_CLK)) {
+ struct device_node *np = i2c->dev.of_node;
+ wm8904->sysclk_from_mclk + of_property_read_bool(np, "wlf,sysclk-from-mclk");
+ if (wm8904->sysclk_from_mclk) {
+ wm8904->mclk_use_xtal + of_property_read_bool(np, "wlf,mclk-use-xtal");
+
+ ret = of_property_read_u32(np, "wlf,mclk-freq",
+ &wm8904->mclk_freq);
+ if (ret) {
+ dev_err(&i2c->dev, "Failed to read mclk freq");
+ goto err_enable;
+ }
+
+ if (!wm8904->mclk_use_xtal) {
+ 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;
+ }
+
+ clk_set_rate(wm8904->mclk, wm8904->mclk_freq);
+ }
+ }
+ }
+
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);
--
1.8.5.2