diff mbox

[v2] ASoC: rk3399_gru_sound: fix recording pop at first attempt

Message ID 1474552206-31742-1-git-send-email-zhengxing@rock-chips.com (mailing list archive)
State New, archived
Headers show

Commit Message

zhengxing Sept. 22, 2016, 1:50 p.m. UTC
From: Wonjoon Lee <woojoo.lee@samsung.com>

Pop happens when mclk applied but dmic's own boot-time
Specify dmic delay times in dt to make sure
clocks are ready earlier than dmic working

Signed-off-by: Wonjoon Lee <woojoo.lee@samsung.com>
Signed-off-by: Xing Zheng <zhengxing@rock-chips.com>
---

Changes in v2:
- rename dmic-delay to dmic-wakeup-delay-ms

 .../bindings/sound/rockchip,rk3399-gru-sound.txt           |  7 +++++++
 sound/soc/rockchip/rk3399_gru_sound.c                      | 14 ++++++++++++++
 2 files changed, 21 insertions(+)

Comments

Rob Herring (Arm) Sept. 23, 2016, 9:27 p.m. UTC | #1
On Thu, Sep 22, 2016 at 09:50:06PM +0800, Xing Zheng wrote:
> From: Wonjoon Lee <woojoo.lee@samsung.com>
> 
> Pop happens when mclk applied but dmic's own boot-time

This statement doesn't make sense.

> Specify dmic delay times in dt to make sure
> clocks are ready earlier than dmic working

I don't think this really belongs in DT. Seems like better control of 
the init order is needed. Or why not just a fixed delay in the driver?

> 
> Signed-off-by: Wonjoon Lee <woojoo.lee@samsung.com>
> Signed-off-by: Xing Zheng <zhengxing@rock-chips.com>
> ---
> 
> Changes in v2:
> - rename dmic-delay to dmic-wakeup-delay-ms
> 
>  .../bindings/sound/rockchip,rk3399-gru-sound.txt           |  7 +++++++
>  sound/soc/rockchip/rk3399_gru_sound.c                      | 14 ++++++++++++++
>  2 files changed, 21 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/sound/rockchip,rk3399-gru-sound.txt b/Documentation/devicetree/bindings/sound/rockchip,rk3399-gru-sound.txt
> index f19b6c8..eac91db 100644
> --- a/Documentation/devicetree/bindings/sound/rockchip,rk3399-gru-sound.txt
> +++ b/Documentation/devicetree/bindings/sound/rockchip,rk3399-gru-sound.txt
> @@ -6,10 +6,17 @@ Required properties:
>    connected to the codecs
>  - rockchip,codec: The phandle of the MAX98357A/RT5514/DA7219 codecs
>  
> +Optional properties:
> +- dmic-wakeup-delay-ms : specify delay time (ms) for DMIC ready.
> +  If this option is specified, which means it's required dmic need
> +  delay for DMIC to ready so that rt5514 can avoid recording before
> +  DMIC send valid data
> +
>  Example:
>  
>  sound {
>  	compatible = "rockchip,rk3399-gru-sound";
>  	rockchip,cpu = <&i2s0>;
>  	rockchip,codec = <&max98357a &rt5514 &da7219>;
> +	dmic-wakeup-delay-ms = <20>;
>  };
> diff --git a/sound/soc/rockchip/rk3399_gru_sound.c b/sound/soc/rockchip/rk3399_gru_sound.c
> index ee06489..9ed735a 100644
> --- a/sound/soc/rockchip/rk3399_gru_sound.c
> +++ b/sound/soc/rockchip/rk3399_gru_sound.c
> @@ -38,6 +38,8 @@
>  
>  #define SOUND_FS	256
>  
> +unsigned int rt5514_dmic_delay;
> +
>  static struct snd_soc_jack rockchip_sound_jack;
>  
>  static const struct snd_soc_dapm_widget rockchip_dapm_widgets[] = {
> @@ -123,6 +125,9 @@ static int rockchip_sound_rt5514_hw_params(struct snd_pcm_substream *substream,
>  		return ret;
>  	}
>  
> +	/* Wait for DMIC stable */
> +	msleep(rt5514_dmic_delay);
> +
>  	return 0;
>  }
>  
> @@ -343,6 +348,15 @@ static int rockchip_sound_probe(struct platform_device *pdev)
>  		return -ENODEV;
>  	}
>  
> +	/* Set DMIC delay */
> +	ret = device_property_read_u32(&pdev->dev, "dmic-delay",

Obviously, this doesn't work now...

> +					&rt5514_dmic_delay);
> +	if (ret) {
> +		rt5514_dmic_delay = 0;
> +		dev_dbg(&pdev->dev,
> +			"no optional property 'dmic-delay' found, default: no delay\n");
> +	}
> +
>  	rockchip_dailinks[DAILINK_RT5514_DSP].cpu_name = kstrdup_const(dev_name(dev), GFP_KERNEL);
>  	rockchip_dailinks[DAILINK_RT5514_DSP].cpu_dai_name = kstrdup_const(dev_name(dev), GFP_KERNEL);
>  	rockchip_dailinks[DAILINK_RT5514_DSP].platform_name = kstrdup_const(dev_name(dev), GFP_KERNEL);
> -- 
> 1.9.1
> 
>
Mark Brown Sept. 24, 2016, 6:10 p.m. UTC | #2
On Fri, Sep 23, 2016 at 04:27:37PM -0500, Rob Herring wrote:
> On Thu, Sep 22, 2016 at 09:50:06PM +0800, Xing Zheng wrote:
> > From: Wonjoon Lee <woojoo.lee@samsung.com>

> > Pop happens when mclk applied but dmic's own boot-time

> This statement doesn't make sense.

It is very clear if you're familiar with the problem domain - because a
DMIC is digital it's got an on/off state which means that when it
transitions from off and not outputting anything to outputting something
you get a sudden DC transition which manifests as a pop in the audio
output.

> > Specify dmic delay times in dt to make sure
> > clocks are ready earlier than dmic working

> I don't think this really belongs in DT. Seems like better control of 
> the init order is needed. Or why not just a fixed delay in the driver?

The changelog says this is due to the DMICs having a startup time of
their own so needing a delay after they've started.  That's going to be
a system dependent thing since it'll depend on the specific component
selected and DMICs are easily interchangable.
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/sound/rockchip,rk3399-gru-sound.txt b/Documentation/devicetree/bindings/sound/rockchip,rk3399-gru-sound.txt
index f19b6c8..eac91db 100644
--- a/Documentation/devicetree/bindings/sound/rockchip,rk3399-gru-sound.txt
+++ b/Documentation/devicetree/bindings/sound/rockchip,rk3399-gru-sound.txt
@@ -6,10 +6,17 @@  Required properties:
   connected to the codecs
 - rockchip,codec: The phandle of the MAX98357A/RT5514/DA7219 codecs
 
+Optional properties:
+- dmic-wakeup-delay-ms : specify delay time (ms) for DMIC ready.
+  If this option is specified, which means it's required dmic need
+  delay for DMIC to ready so that rt5514 can avoid recording before
+  DMIC send valid data
+
 Example:
 
 sound {
 	compatible = "rockchip,rk3399-gru-sound";
 	rockchip,cpu = <&i2s0>;
 	rockchip,codec = <&max98357a &rt5514 &da7219>;
+	dmic-wakeup-delay-ms = <20>;
 };
diff --git a/sound/soc/rockchip/rk3399_gru_sound.c b/sound/soc/rockchip/rk3399_gru_sound.c
index ee06489..9ed735a 100644
--- a/sound/soc/rockchip/rk3399_gru_sound.c
+++ b/sound/soc/rockchip/rk3399_gru_sound.c
@@ -38,6 +38,8 @@ 
 
 #define SOUND_FS	256
 
+unsigned int rt5514_dmic_delay;
+
 static struct snd_soc_jack rockchip_sound_jack;
 
 static const struct snd_soc_dapm_widget rockchip_dapm_widgets[] = {
@@ -123,6 +125,9 @@  static int rockchip_sound_rt5514_hw_params(struct snd_pcm_substream *substream,
 		return ret;
 	}
 
+	/* Wait for DMIC stable */
+	msleep(rt5514_dmic_delay);
+
 	return 0;
 }
 
@@ -343,6 +348,15 @@  static int rockchip_sound_probe(struct platform_device *pdev)
 		return -ENODEV;
 	}
 
+	/* Set DMIC delay */
+	ret = device_property_read_u32(&pdev->dev, "dmic-delay",
+					&rt5514_dmic_delay);
+	if (ret) {
+		rt5514_dmic_delay = 0;
+		dev_dbg(&pdev->dev,
+			"no optional property 'dmic-delay' found, default: no delay\n");
+	}
+
 	rockchip_dailinks[DAILINK_RT5514_DSP].cpu_name = kstrdup_const(dev_name(dev), GFP_KERNEL);
 	rockchip_dailinks[DAILINK_RT5514_DSP].cpu_dai_name = kstrdup_const(dev_name(dev), GFP_KERNEL);
 	rockchip_dailinks[DAILINK_RT5514_DSP].platform_name = kstrdup_const(dev_name(dev), GFP_KERNEL);