[PATCH v1 2/2] ASoC: rt5640: add master clock handling for rt5640

From: Sugar Zhang
Date: Mon Feb 22 2016 - 03:03:35 EST


enable/disable master clock when codec is active or not.

Signed-off-by: Sugar Zhang <sugar.zhang@xxxxxxxxxxxxxx>
---

Documentation/devicetree/bindings/sound/rt5640.txt | 3 +++
sound/soc/codecs/rt5640.c | 31 ++++++++++++++++++++++
sound/soc/codecs/rt5640.h | 2 ++
3 files changed, 36 insertions(+)

diff --git a/Documentation/devicetree/bindings/sound/rt5640.txt b/Documentation/devicetree/bindings/sound/rt5640.txt
index 9e62f6e..57fe646 100644
--- a/Documentation/devicetree/bindings/sound/rt5640.txt
+++ b/Documentation/devicetree/bindings/sound/rt5640.txt
@@ -12,6 +12,9 @@ Required properties:

Optional properties:

+- clocks: The phandle of the master clock to the CODEC
+- clock-names: Should be "mclk"
+
- realtek,in1-differential
- realtek,in2-differential
- realtek,in3-differential
diff --git a/sound/soc/codecs/rt5640.c b/sound/soc/codecs/rt5640.c
index 11d032c..6cd84fb 100644
--- a/sound/soc/codecs/rt5640.c
+++ b/sound/soc/codecs/rt5640.c
@@ -1949,7 +1949,33 @@ static int rt5640_set_dai_pll(struct snd_soc_dai *dai, int pll_id, int source,
static int rt5640_set_bias_level(struct snd_soc_codec *codec,
enum snd_soc_bias_level level)
{
+ struct rt5640_priv *rt5640 = snd_soc_codec_get_drvdata(codec);
+ int ret;
+
switch (level) {
+ case SND_SOC_BIAS_ON:
+ break;
+
+ case SND_SOC_BIAS_PREPARE:
+ /*
+ * SND_SOC_BIAS_PREPARE is called while preparing for a
+ * transition to ON or away from ON. If current bias_level
+ * is SND_SOC_BIAS_ON, then it is preparing for a transition
+ * away from ON. Disable the clock in that case, otherwise
+ * enable it.
+ */
+ if (IS_ERR(rt5640->mclk))
+ break;
+
+ if (snd_soc_codec_get_bias_level(codec) == SND_SOC_BIAS_ON) {
+ clk_disable_unprepare(rt5640->mclk);
+ } else {
+ ret = clk_prepare_enable(rt5640->mclk);
+ if (ret)
+ return ret;
+ }
+ break;
+
case SND_SOC_BIAS_STANDBY:
if (SND_SOC_BIAS_OFF == snd_soc_codec_get_bias_level(codec)) {
snd_soc_update_bits(codec, RT5640_PWR_ANLG1,
@@ -2088,6 +2114,11 @@ static int rt5640_probe(struct snd_soc_codec *codec)
struct snd_soc_dapm_context *dapm = snd_soc_codec_get_dapm(codec);
struct rt5640_priv *rt5640 = snd_soc_codec_get_drvdata(codec);

+ /* Check if MCLK provided */
+ rt5640->mclk = devm_clk_get(codec->dev, "mclk");
+ if (PTR_ERR(rt5640->mclk) == -EPROBE_DEFER)
+ return -EPROBE_DEFER;
+
rt5640->codec = codec;

snd_soc_codec_force_bias_level(codec, SND_SOC_BIAS_OFF);
diff --git a/sound/soc/codecs/rt5640.h b/sound/soc/codecs/rt5640.h
index 83a7150..1761c3a9 100644
--- a/sound/soc/codecs/rt5640.h
+++ b/sound/soc/codecs/rt5640.h
@@ -12,6 +12,7 @@
#ifndef _RT5640_H
#define _RT5640_H

+#include <linux/clk.h>
#include <sound/rt5640.h>

/* Info */
@@ -2097,6 +2098,7 @@ struct rt5640_priv {
struct snd_soc_codec *codec;
struct rt5640_platform_data pdata;
struct regmap *regmap;
+ struct clk *mclk;

int sysclk;
int sysclk_src;
--
1.9.1