[alsa-devel] [PATCH v2] ASoC: wm8994: Manage wm8994's MCLK in codec driver

[alsa-devel] [PATCH v2] ASoC: wm8994: Manage wm8994's MCLK in codec driver

[Inha Song]

Previously, When we use wm8994 codec, we should control its MCLK in machine driver.
But, It should be managed by wm8994 codec driver, not machine driver.

This patch add MCLK clock DT parsing logic and control own MCLK.

Signed-off-by: Inha Song <ideal.song@samsung.com>
---
 sound/soc/codecs/wm8994.c | 22 +++++++++++++++++++++-
 sound/soc/codecs/wm8994.h |  1 +
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/sound/soc/codecs/wm8994.c b/sound/soc/codecs/wm8994.c
index 4fbc768..acb6b44 100644
--- a/sound/soc/codecs/wm8994.c
+++ b/sound/soc/codecs/wm8994.c
@@ -16,6 +16,7 @@
 #include <linux/init.h>
 #include <linux/delay.h>
 #include <linux/pm.h>
+#include <linux/clk.h>
 #include <linux/gcd.h>
 #include <linux/i2c.h>
 #include <linux/platform_device.h>
@@ -2471,6 +2472,7 @@ static int wm8994_set_bias_level(struct snd_soc_codec *codec,
 {
 	struct wm8994_priv *wm8994 = snd_soc_codec_get_drvdata(codec);
 	struct wm8994 *control = wm8994->wm8994;
+	int i;
 
 	wm_hubs_set_bias_level(codec, level);
 
@@ -2492,8 +2494,15 @@ static int wm8994_set_bias_level(struct snd_soc_codec *codec,
 			break;
 		}
 
-		if (codec->dapm.bias_level == SND_SOC_BIAS_STANDBY)
+		if (codec->dapm.bias_level == SND_SOC_BIAS_STANDBY) {
+			for (i = 0; i < ARRAY_SIZE(wm8994->clk_mclk); i++)
+				clk_prepare_enable(wm8994->clk_mclk[i]);
+
 			active_reference(codec);
+		} else if (codec->dapm.bias_level == SND_SOC_BIAS_ON) {
+			for (i = 0; i < ARRAY_SIZE(wm8994->clk_mclk); i++)
+				clk_disable_unprepare(wm8994->clk_mclk[i]);
+		}
 		break;
 
 	case SND_SOC_BIAS_STANDBY:
@@ -4449,6 +4458,7 @@ static struct snd_soc_codec_driver soc_codec_dev_wm8994 = {
 static int wm8994_probe(struct platform_device *pdev)
 {
 	struct wm8994_priv *wm8994;
+	int i;
 
 	wm8994 = devm_kzalloc(&pdev->dev, sizeof(struct wm8994_priv),
 			      GFP_KERNEL);
@@ -4460,6 +4470,16 @@ static int wm8994_probe(struct platform_device *pdev)
 
 	wm8994->wm8994 = dev_get_drvdata(pdev->dev.parent);
 
+	for (i = 0; i < ARRAY_SIZE(wm8994->clk_mclk); i++) {
+		char mclk_name[] = "MCLKx";
+
+		snprintf(mclk_name, sizeof(mclk_name), "MCLK%d", i + 1);
+
+		wm8994->clk_mclk[i] = devm_clk_get(pdev->dev.parent, mclk_name);
+		if (IS_ERR(wm8994->clk_mclk[i]))
+			wm8994->clk_mclk[i] = NULL;
+	}
+
 	pm_runtime_enable(&pdev->dev);
 	pm_runtime_idle(&pdev->dev);
 
diff --git a/sound/soc/codecs/wm8994.h b/sound/soc/codecs/wm8994.h
index dd73387..d426c44 100644
--- a/sound/soc/codecs/wm8994.h
+++ b/sound/soc/codecs/wm8994.h
@@ -79,6 +79,7 @@ struct wm8994_priv {
 	int sysclk[2];
 	int sysclk_rate[2];
 	int mclk[2];
+	struct clk *clk_mclk[2];
 	int aifclk[2];
 	int aifdiv[2];
 	int channels[2];
-- 
2.0.0.390.gcb682f8

Re: [alsa-devel] [PATCH v2] ASoC: wm8994: Manage wm8994's MCLK in codec driver

[Charles Keepax]

On Thu, Mar 12, 2015 at 07:46:21PM +0900, Inha Song wrote:
> Previously, When we use wm8994 codec, we should control its MCLK in machine driver.
> But, It should be managed by wm8994 codec driver, not machine driver.
> 
> This patch add MCLK clock DT parsing logic and control own MCLK.
> 
> Signed-off-by: Inha Song <ideal.song@samsung.com>
> ---
>  sound/soc/codecs/wm8994.c | 22 +++++++++++++++++++++-
>  sound/soc/codecs/wm8994.h |  1 +
>  2 files changed, 22 insertions(+), 1 deletion(-)
> 
> diff --git a/sound/soc/codecs/wm8994.c b/sound/soc/codecs/wm8994.c
> index 4fbc768..acb6b44 100644
> --- a/sound/soc/codecs/wm8994.c
> +++ b/sound/soc/codecs/wm8994.c
> @@ -16,6 +16,7 @@
>  #include <linux/init.h>
>  #include <linux/delay.h>
>  #include <linux/pm.h>
> +#include <linux/clk.h>
>  #include <linux/gcd.h>
>  #include <linux/i2c.h>
>  #include <linux/platform_device.h>
> @@ -2471,6 +2472,7 @@ static int wm8994_set_bias_level(struct snd_soc_codec *codec,
>  {
>  	struct wm8994_priv *wm8994 = snd_soc_codec_get_drvdata(codec);
>  	struct wm8994 *control = wm8994->wm8994;
> +	int i;
>  
>  	wm_hubs_set_bias_level(codec, level);
>  
> @@ -2492,8 +2494,15 @@ static int wm8994_set_bias_level(struct snd_soc_codec *codec,
>  			break;
>  		}
>  
> -		if (codec->dapm.bias_level == SND_SOC_BIAS_STANDBY)
> +		if (codec->dapm.bias_level == SND_SOC_BIAS_STANDBY) {
> +			for (i = 0; i < ARRAY_SIZE(wm8994->clk_mclk); i++)
> +				clk_prepare_enable(wm8994->clk_mclk[i]);

This still looks like you need some response to Mark's comments.

> +
>  			active_reference(codec);
> +		} else if (codec->dapm.bias_level == SND_SOC_BIAS_ON) {
> +			for (i = 0; i < ARRAY_SIZE(wm8994->clk_mclk); i++)
> +				clk_disable_unprepare(wm8994->clk_mclk[i]);
> +		}
>  		break;
>  
>  	case SND_SOC_BIAS_STANDBY:
> @@ -4449,6 +4458,7 @@ static struct snd_soc_codec_driver soc_codec_dev_wm8994 = {
>  static int wm8994_probe(struct platform_device *pdev)
>  {
>  	struct wm8994_priv *wm8994;
> +	int i;
>  
>  	wm8994 = devm_kzalloc(&pdev->dev, sizeof(struct wm8994_priv),
>  			      GFP_KERNEL);
> @@ -4460,6 +4470,16 @@ static int wm8994_probe(struct platform_device *pdev)
>  
>  	wm8994->wm8994 = dev_get_drvdata(pdev->dev.parent);
>  
> +	for (i = 0; i < ARRAY_SIZE(wm8994->clk_mclk); i++) {
> +		char mclk_name[] = "MCLKx";
> +
> +		snprintf(mclk_name, sizeof(mclk_name), "MCLK%d", i + 1);
> +
> +		wm8994->clk_mclk[i] = devm_clk_get(pdev->dev.parent, mclk_name);
> +		if (IS_ERR(wm8994->clk_mclk[i]))
> +			wm8994->clk_mclk[i] = NULL;

This still looks wrong, devm_clk_get will return an -ENOENT if it
can't find a clock, but any other error is surely an actual error
that we should fail on?

Thanks,
Charles