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[PATCH v2] ALSA: hda/conexant: Fix pop noise on conexant codec

wangdich9700@163.com posted 1 patch 1 month, 2 weeks ago 
sound/hda/codecs/conexant.c | 65 +++++++++++++++++++++++++++++++++++++
1 file changed, 65 insertions(+)
[PATCH v2] ALSA: hda/conexant: Fix pop noise on conexant codec
Posted by wangdich9700@163.com 1 month, 2 weeks ago 
From: wangdicheng <wangdich9700@163.com>

Pop noise mitigation: When headphones are unplugged during playback,mute
speaker DAC(0x17)immediately and restore after 20ms delay to avoid
audible popping.

Signed-off-by: wangdicheng <wangdicheng@kylinos.cn>
---
 sound/hda/codecs/conexant.c | 65 +++++++++++++++++++++++++++++++++++++
 1 file changed, 65 insertions(+)

diff --git a/sound/hda/codecs/conexant.c b/sound/hda/codecs/conexant.c
index 5fcbc1312c69..2c16d1930a75 100644
--- a/sound/hda/codecs/conexant.c
+++ b/sound/hda/codecs/conexant.c
@@ -43,6 +43,9 @@ struct conexant_spec {
 	unsigned int gpio_mute_led_mask;
 	unsigned int gpio_mic_led_mask;
 	bool is_cx11880_sn6140;
+
+	struct hda_codec *conexant_codec;
+	struct delayed_work change_pinctl_work;
 };
 
 
@@ -216,6 +219,63 @@ static void cx_remove(struct hda_codec *codec)
 	snd_hda_gen_remove(codec);
 }
 
+static void mute_unmute_speaker(struct hda_codec *codec, hda_nid_t nid, bool mute)
+{
+	unsigned int conn_sel, dac, conn_list, gain_left, gain_right;
+
+	conn_sel = snd_hda_codec_read(codec, nid, 0, 0xf01, 0x0);
+	conn_list = snd_hda_codec_read(codec, nid, 0, 0xf02, 0x0);
+
+	dac = ((conn_list >> (conn_sel * 8)) & 0xff);
+	if (dac == 0)
+		return;
+
+	gain_left = snd_hda_codec_read(codec, dac, 0, 0xba0, 0x0);
+	gain_right = snd_hda_codec_read(codec, dac, 0, 0xb80, 0x0);
+
+	if (mute) {
+		gain_left |= 0x80;
+		gain_right |= 0x80;
+	} else {
+		gain_left &= (~(0x80));
+		gain_right &= (~(0x80));
+	}
+
+	snd_hda_codec_write(codec, dac, 0, 0x3a0, gain_left);
+	snd_hda_codec_write(codec, dac, 0, 0x390, gain_right);
+
+	if (mute) {
+		snd_hda_codec_write(codec, nid, 0, 0x707, 0);
+		codec_dbg(codec, "mute_speaker, set 0x%x  PinCtrl to 0.\n", nid);
+	} else {
+		snd_hda_codec_write(codec, nid, 0, 0x707, 0x40);
+		codec_dbg(codec, "unmute_speaker, set 0x%x  PinCtrl to 0x40.\n", nid);
+	}
+}
+
+static void change_pinctl_worker(struct work_struct *work)
+{
+	struct hda_codec *codec;
+	struct conexant_spec *spec;
+
+	spec = container_of(work, struct conexant_spec, change_pinctl_work.work);
+	codec = spec->conexant_codec;
+
+	return mute_unmute_speaker(codec, 0x17, false);
+}
+
+static void cx_auto_mute_unmute_speaker(struct hda_codec *codec, struct hda_jack_callback *event)
+{
+	struct conexant_spec *spec = codec->spec;
+	int phone_present;
+
+	phone_present = snd_hda_codec_read(codec, 0x16, 0, 0xf09, 0x0);
+	if (!(phone_present & 0x80000000)) {
+		mute_unmute_speaker(codec, 0x17, true);
+		schedule_delayed_work(&spec->change_pinctl_work, 20);
+	}
+}
+
 static void cx_process_headset_plugin(struct hda_codec *codec)
 {
 	unsigned int val;
@@ -1178,6 +1238,10 @@ static int cx_probe(struct hda_codec *codec, const struct hda_device_id *id)
 	spec = kzalloc(sizeof(*spec), GFP_KERNEL);
 	if (!spec)
 		return -ENOMEM;
+
+	INIT_DELAYED_WORK(&spec->change_pinctl_work, change_pinctl_worker);
+	spec->conexant_codec = codec;
+
 	snd_hda_gen_spec_init(&spec->gen);
 	codec->spec = spec;
 
@@ -1187,6 +1251,7 @@ static int cx_probe(struct hda_codec *codec, const struct hda_device_id *id)
 	case 0x14f11f87:
 		spec->is_cx11880_sn6140 = true;
 		snd_hda_jack_detect_enable_callback(codec, 0x19, cx_update_headset_mic_vref);
+		snd_hda_jack_detect_enable_callback(codec, 0x16, cx_auto_mute_unmute_speaker);
 		break;
 	}
 
-- 
2.25.1
Re: [PATCH v2] ALSA: hda/conexant: Fix pop noise on conexant codec
Posted by Cezary Rojewski 1 month, 1 week ago 
On 2025-11-05 3:25 AM, wangdich9700@163.com wrote:
> From: wangdicheng <wangdich9700@163.com>
> 
> Pop noise mitigation: When headphones are unplugged during playback,mute
> speaker DAC(0x17)immediately and restore after 20ms delay to avoid
> audible popping.

What's the device ID for the "conexant codec"? I doubt all of them share 
the problem. Once obtained, mention the ID within the title.

Now, the problem you're aiming to address seem generic - addressing pop 
noises during plug/unplug is a common subject in sound/ domain. I'd 
check if sound/hda/codecs doesn't have something for such occasion 
already. Takashi is more fluent in sound/hda, perhaps he could help here.

If such code exists, you could get rid of ugly:
	codec->spec <-> spec->codec

relation which you're adding with:
	struct hda_codec *conexant_codec;

> 
> Signed-off-by: wangdicheng <wangdicheng@kylinos.cn>
> ---
>   sound/hda/codecs/conexant.c | 65 +++++++++++++++++++++++++++++++++++++
>   1 file changed, 65 insertions(+)
> 
> diff --git a/sound/hda/codecs/conexant.c b/sound/hda/codecs/conexant.c
> index 5fcbc1312c69..2c16d1930a75 100644
> --- a/sound/hda/codecs/conexant.c
> +++ b/sound/hda/codecs/conexant.c
> @@ -43,6 +43,9 @@ struct conexant_spec {
>   	unsigned int gpio_mute_led_mask;
>   	unsigned int gpio_mic_led_mask;
>   	bool is_cx11880_sn6140;
> +
> +	struct hda_codec *conexant_codec;
> +	struct delayed_work change_pinctl_work;

Not fan of adding 'struct hda_codec *' as part of the spec. As stated 
above, I'd first check if something pop noise -related doesn't exist in 
sound/hda already. If it does, hook into it.

>   };
>   
>   
> @@ -216,6 +219,63 @@ static void cx_remove(struct hda_codec *codec)
>   	snd_hda_gen_remove(codec);
>   }
>   
> +static void mute_unmute_speaker(struct hda_codec *codec, hda_nid_t nid, bool mute)
> +{
> +	unsigned int conn_sel, dac, conn_list, gain_left, gain_right;
> +
> +	conn_sel = snd_hda_codec_read(codec, nid, 0, 0xf01, 0x0);
> +	conn_list = snd_hda_codec_read(codec, nid, 0, 0xf02, 0x0);
> +
> +	dac = ((conn_list >> (conn_sel * 8)) & 0xff);
> +	if (dac == 0)
> +		return;
> +
> +	gain_left = snd_hda_codec_read(codec, dac, 0, 0xba0, 0x0);
> +	gain_right = snd_hda_codec_read(codec, dac, 0, 0xb80, 0x0);
> +
> +	if (mute) {
> +		gain_left |= 0x80;
> +		gain_right |= 0x80;
> +	} else {
> +		gain_left &= (~(0x80));
> +		gain_right &= (~(0x80));
> +	}
> +
> +	snd_hda_codec_write(codec, dac, 0, 0x3a0, gain_left);
> +	snd_hda_codec_write(codec, dac, 0, 0x390, gain_right);
> +
> +	if (mute) {
> +		snd_hda_codec_write(codec, nid, 0, 0x707, 0);
> +		codec_dbg(codec, "mute_speaker, set 0x%x  PinCtrl to 0.\n", nid);
> +	} else {
> +		snd_hda_codec_write(codec, nid, 0, 0x707, 0x40);
> +		codec_dbg(codec, "unmute_speaker, set 0x%x  PinCtrl to 0x40.\n", nid);
> +	}
> +}
> +
> +static void change_pinctl_worker(struct work_struct *work)
> +{
> +	struct hda_codec *codec;
> +	struct conexant_spec *spec;
> +
> +	spec = container_of(work, struct conexant_spec, change_pinctl_work.work);
> +	codec = spec->conexant_codec;
> +
> +	return mute_unmute_speaker(codec, 0x17, false);

return-statement in void? The code won't compile. Was the patch tested 
at all?

> +}

Patchew 2.1-devel-b67e4c2

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