[PATCH v3 0/3] ASoC: soc-core: Add core support for ignoring suspend on selected DAPM widgets

[PATCH v3 0/3] ASoC: soc-core: Add core support for ignoring suspend on selected DAPM widgets

[Chancel Liu]

Some audio systems require specific DAPM widgets to remain powered
during system suspend. Introduce a generic and reusable mechanism in
the ASoC core to mark selected DAPM widgets as ignore_suspend.

The unified mechanism consists of two parts:
1. Parse and store the name list of widgets to ignore suspend in
struct snd_soc_card

The list of widgets can be provided either by the machine driver or
parsed from Device Tree. Different machines have different routing and
power requirements. Each machine can specify its own widgets to ignore
suspend through DT property. It enables flexible policy without hard
code. A new helper, snd_soc_of_parse_ignore_suspend_widgets() is added
for this purpose.

2. Apply ignore_suspend flags during snd_soc_bind_card()

After all components have been probed and all DAPM widgets have been
registered, snd_soc_bind_card() performs a unified lookup of the
configured widget names across all DAPM contexts of the card and marks
the matching widgets with ignore_suspend = 1.

Switch to use core ignore-suspend-widgets support for imx-rpmsg driver.

Changes in v3:
- Reword first patch subject to use snd_soc_dapm_widget_name_cmp()
- Use goto fail for error handling in imx_rpmsg_probe() to ensure proper
cleanup of of_node references

The v2 series is a rework of the previous "[PATCH] ASoC: imx-rpmsg:
Fix ignore-suspend-widgets only applied to codec DAPM".
Changes in v2:
- Rework to use a unified core mechanism instead of machine driver
specific code

Chancel Liu (3):
  ASoC: dapm: Fix widget lookup with snd_soc_dapm_widget_name_cmp()
  ASoC: soc-core: Add core support for ignoring suspend on selected DAPM
    widgets
  ASoC: fsl: imx-rpmsg: Switch to core ignore-suspend-widgets support

 include/sound/soc-dapm.h  |  1 +
 include/sound/soc.h       |  5 +++++
 sound/soc/fsl/imx-rpmsg.c | 26 ++++++++---------------
 sound/soc/soc-core.c      | 43 +++++++++++++++++++++++++++++++++++++++
 sound/soc/soc-dapm.c      | 43 ++++++++++++++++++++++++++++-----------
 5 files changed, 89 insertions(+), 29 deletions(-)

--
2.50.1

[PATCH v3 1/3] ASoC: dapm: Fix widget lookup with snd_soc_dapm_widget_name_cmp()

[Chancel Liu]

Currently dapm_find_widget() manually constructs a prefixed widget name
based on the provided DAPM context and compares it using strcmp(). This
happens to work in most cases because callers usually know which DAPM
context the target widget belongs to and pass in the matching DAPM
context.

However, this assumption breaks when search_other_contexts is enabled.
In such cases, callers may intentionally pass a different DAPM context,
while searching for a widget that actually belongs to another DAPM
context.

For example, when searching for a "DAC" widget, the widget belongs to
the codec DAPM and be registered with a codec prefix, while the caller
passes card->dapm and intends to search across all DAPM contexts. The
current implementation incorrectly applies the caller card DAPM causing
the lookup to fail even though the widget exists on the card.

Use snd_soc_dapm_widget_name_cmp() instead, which compares widget names
using the widget's own DAPM context and prefix. It fixes widget lookup
failures when searching across different DAPM contexts on the card.

Fixes: ae4fc532244b ("ASoC: dapm: use component prefix when checking widget names")
Signed-off-by: Chancel Liu <chancel.liu@nxp.com>
Assisted-by: Cody:Claude-3.5-Sonnet
---
 sound/soc/soc-dapm.c | 13 +------------
 1 file changed, 1 insertion(+), 12 deletions(-)

diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c
index d6192204e613..c5b80d9ed64b 100644
--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -2906,20 +2906,9 @@ static struct snd_soc_dapm_widget *dapm_find_widget(
 {
 	struct snd_soc_dapm_widget *w;
 	struct snd_soc_dapm_widget *fallback = NULL;
-	char prefixed_pin[80];
-	const char *pin_name;
-	const char *prefix = dapm_prefix(dapm);
-
-	if (prefix) {
-		snprintf(prefixed_pin, sizeof(prefixed_pin), "%s %s",
-			 prefix, pin);
-		pin_name = prefixed_pin;
-	} else {
-		pin_name = pin;
-	}
 
 	for_each_card_widgets(dapm->card, w) {
-		if (!strcmp(w->name, pin_name)) {
+		if (!snd_soc_dapm_widget_name_cmp(w, pin)) {
 			if (w->dapm == dapm)
 				return w;
 			else
-- 
2.50.1

[PATCH v3 2/3] ASoC: soc-core: Add core support for ignoring suspend on selected DAPM widgets

[Chancel Liu]

Some audio systems require specific DAPM widgets to remain powered
during system suspend. Introduce a generic and reusable mechanism in
the ASoC core to mark selected DAPM widgets as ignore_suspend.

The unified mechanism consists of two parts:
1. Parse and store the name list of widgets to ignore suspend in
struct snd_soc_card

The list of widgets can be provided either by the machine driver or
parsed from Device Tree. Different machines have different routing and
power requirements. Each machine can specify its own widgets to ignore
suspend through DT property. It enables flexible policy without hard
code. A new helper, snd_soc_of_parse_ignore_suspend_widgets() is added
for this purpose.

2. Apply ignore_suspend flags during snd_soc_bind_card()

After all components have been probed and all DAPM widgets have been
registered, snd_soc_bind_card() performs a unified lookup of the
configured widget names across all DAPM contexts of the card and marks
the matching widgets with ignore_suspend = 1.

Signed-off-by: Chancel Liu <chancel.liu@nxp.com>
---
 include/sound/soc-dapm.h |  1 +
 include/sound/soc.h      |  5 +++++
 sound/soc/soc-core.c     | 43 ++++++++++++++++++++++++++++++++++++++++
 sound/soc/soc-dapm.c     | 30 ++++++++++++++++++++++++++++
 4 files changed, 79 insertions(+)

diff --git a/include/sound/soc-dapm.h b/include/sound/soc-dapm.h
index 4f8fb7622a13..39c290e0eb7f 100644
--- a/include/sound/soc-dapm.h
+++ b/include/sound/soc-dapm.h
@@ -636,6 +636,7 @@ int snd_soc_dapm_new_dai_widgets(struct snd_soc_dapm_context *dapm, struct snd_s
 void snd_soc_dapm_free_widget(struct snd_soc_dapm_widget *w);
 int snd_soc_dapm_link_dai_widgets(struct snd_soc_card *card);
 void snd_soc_dapm_connect_dai_link_widgets(struct snd_soc_card *card);
+int snd_soc_dapm_ignore_suspend_widgets(struct snd_soc_card *card);
 
 int snd_soc_dapm_update_dai(struct snd_pcm_substream *substream,
 			    struct snd_pcm_hw_params *params, struct snd_soc_dai *dai);
diff --git a/include/sound/soc.h b/include/sound/soc.h
index 5e3eb617d832..7d6fa79f48e3 100644
--- a/include/sound/soc.h
+++ b/include/sound/soc.h
@@ -1057,10 +1057,14 @@ struct snd_soc_card {
 	int num_dapm_widgets;
 	const struct snd_soc_dapm_route *dapm_routes;
 	int num_dapm_routes;
+	const char **ignore_suspend_widgets;
+	int num_ignore_suspend_widgets;
 	const struct snd_soc_dapm_widget *of_dapm_widgets;
 	int num_of_dapm_widgets;
 	const struct snd_soc_dapm_route *of_dapm_routes;
 	int num_of_dapm_routes;
+	const char **of_ignore_suspend_widgets;
+	int num_of_ignore_suspend_widgets;
 
 	/* lists of probed devices belonging to this card */
 	struct list_head component_dev_list;
@@ -1339,6 +1343,7 @@ void snd_soc_of_parse_node_prefix(struct device_node *np,
 int snd_soc_of_parse_audio_routing(struct snd_soc_card *card,
 				   const char *propname);
 int snd_soc_of_parse_aux_devs(struct snd_soc_card *card, const char *propname);
+int snd_soc_of_parse_ignore_suspend_widgets(struct snd_soc_card *card, const char *propname);
 
 unsigned int snd_soc_daifmt_clock_provider_flipped(unsigned int dai_fmt);
 unsigned int snd_soc_daifmt_clock_provider_from_bitmap(unsigned int bit_frame);
diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
index 3fecf9fc903c..705181dae472 100644
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -2289,6 +2289,10 @@ static int snd_soc_bind_card(struct snd_soc_card *card)
 	if (ret < 0)
 		goto probe_end;
 
+	ret = snd_soc_dapm_ignore_suspend_widgets(card);
+	if (ret < 0)
+		goto probe_end;
+
 	snd_soc_dapm_new_widgets(card);
 	snd_soc_card_fixup_controls(card);
 
@@ -3294,6 +3298,45 @@ int snd_soc_of_parse_aux_devs(struct snd_soc_card *card, const char *propname)
 }
 EXPORT_SYMBOL_GPL(snd_soc_of_parse_aux_devs);
 
+int snd_soc_of_parse_ignore_suspend_widgets(struct snd_soc_card *card,
+					    const char *propname)
+{
+	struct device_node *np = card->dev->of_node;
+	int num_widgets;
+	const char **widgets;
+	int i;
+
+	num_widgets = of_property_count_strings(np, propname);
+	if (num_widgets < 0) {
+		dev_err(card->dev,
+			"ASoC: Property '%s' does not exist\n", propname);
+		return -EINVAL;
+	}
+
+	widgets = devm_kcalloc(card->dev, num_widgets, sizeof(char *), GFP_KERNEL);
+	if (!widgets)
+		return -ENOMEM;
+
+	for (i = 0; i < num_widgets; i++) {
+		const char *name;
+		int ret = of_property_read_string_index(np, propname, i, &name);
+
+		if (ret) {
+			dev_err(card->dev,
+				"ASoC: Property '%s' could not be read: %d\n",
+				propname, ret);
+			return -EINVAL;
+		}
+		widgets[i] = name;
+	}
+
+	card->num_of_ignore_suspend_widgets = num_widgets;
+	card->of_ignore_suspend_widgets = widgets;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(snd_soc_of_parse_ignore_suspend_widgets);
+
 unsigned int snd_soc_daifmt_clock_provider_flipped(unsigned int dai_fmt)
 {
 	unsigned int inv_dai_fmt = dai_fmt & ~SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK;
diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c
index c5b80d9ed64b..209f86b9add6 100644
--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -4595,6 +4595,36 @@ void snd_soc_dapm_connect_dai_link_widgets(struct snd_soc_card *card)
 	}
 }
 
+int snd_soc_dapm_ignore_suspend_widgets(struct snd_soc_card *card)
+{
+	struct snd_soc_dapm_widget *w;
+	int i;
+
+	for (i = 0; i < card->num_ignore_suspend_widgets; i++) {
+		w = dapm_find_widget(snd_soc_card_to_dapm(card),
+				     card->ignore_suspend_widgets[i], true);
+		if (!w) {
+			dev_err(card->dev, "ASoC: DAPM unknown ignore suspend widget %s\n",
+				card->ignore_suspend_widgets[i]);
+			return -EINVAL;
+		}
+		w->ignore_suspend = 1;
+	}
+
+	for (i = 0; i < card->num_of_ignore_suspend_widgets; i++) {
+		w = dapm_find_widget(snd_soc_card_to_dapm(card),
+				     card->of_ignore_suspend_widgets[i], true);
+		if (!w) {
+			dev_err(card->dev, "ASoC: DAPM unknown ignore suspend widget %s\n",
+				card->of_ignore_suspend_widgets[i]);
+			return -EINVAL;
+		}
+		w->ignore_suspend = 1;
+	}
+
+	return 0;
+}
+
 static void dapm_stream_event(struct snd_soc_pcm_runtime *rtd, int stream, int event)
 {
 	struct snd_soc_dai *dai;
-- 
2.50.1

[PATCH v3 3/3] ASoC: fsl: imx-rpmsg: Switch to core ignore-suspend-widgets support

[Chancel Liu]

The imx-rpmsg machine driver currently implements its own logic to
parse ignore-suspend-widgets from Device Tree and manually traverse
DAPM widgets to mark them as ignore_suspend.

It also has a potential issue that some widgets listed in the property
(e.g. "Headphone Jack") belong to card or CPU DAI DAPM context.

Switch to use snd_soc_of_parse_ignore_suspend_widgets() with the
introduction of a generic ignore-suspend-widgets mechanism in the ASoC
core.

Signed-off-by: Chancel Liu <chancel.liu@nxp.com>
---
 sound/soc/fsl/imx-rpmsg.c | 26 +++++++++-----------------
 1 file changed, 9 insertions(+), 17 deletions(-)

diff --git a/sound/soc/fsl/imx-rpmsg.c b/sound/soc/fsl/imx-rpmsg.c
index 40e0043cfe15..fd4624786b62 100644
--- a/sound/soc/fsl/imx-rpmsg.c
+++ b/sound/soc/fsl/imx-rpmsg.c
@@ -87,7 +87,6 @@ static int imx_rpmsg_late_probe(struct snd_soc_card *card)
 	int ret;
 
 	if (data->lpa) {
-		struct snd_soc_component *codec_comp;
 		struct device_node *codec_np;
 		struct device_driver *codec_drv;
 		struct device *codec_dev = NULL;
@@ -107,22 +106,6 @@ static int imx_rpmsg_late_probe(struct snd_soc_card *card)
 			}
 		}
 		if (codec_dev) {
-			codec_comp = snd_soc_lookup_component_nolocked(codec_dev, NULL);
-			if (codec_comp) {
-				int i, num_widgets;
-				const char *widgets;
-				struct snd_soc_dapm_context *dapm;
-
-				num_widgets = of_property_count_strings(data->card.dev->of_node,
-									"ignore-suspend-widgets");
-				for (i = 0; i < num_widgets; i++) {
-					of_property_read_string_index(data->card.dev->of_node,
-								      "ignore-suspend-widgets",
-								      i, &widgets);
-					dapm = snd_soc_component_to_dapm(codec_comp);
-					snd_soc_dapm_ignore_suspend(dapm, widgets);
-				}
-			}
 			codec_drv = codec_dev->driver;
 			if (codec_drv->pm) {
 				memcpy(&lpa_pm, codec_drv->pm, sizeof(lpa_pm));
@@ -274,6 +257,15 @@ static int imx_rpmsg_probe(struct platform_device *pdev)
 		}
 	}
 
+	if (data->lpa && of_property_present(np, "ignore-suspend-widgets")) {
+		ret = snd_soc_of_parse_ignore_suspend_widgets(&data->card,
+							      "ignore-suspend-widgets");
+		if (ret) {
+			dev_err(&pdev->dev, "failed to parse ignore-suspend-widgets: %d\n", ret);
+			goto fail;
+		}
+	}
+
 	platform_set_drvdata(pdev, &data->card);
 	snd_soc_card_set_drvdata(&data->card, data);
 	ret = devm_snd_soc_register_card(&pdev->dev, &data->card);
-- 
2.50.1

Re: [PATCH v3 1/3] ASoC: dapm: Fix widget lookup with snd_soc_dapm_widget_name_cmp()

[Mark Brown]

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On Wed, Apr 29, 2026 at 11:12:50AM +0900, Chancel Liu wrote:
> Currently dapm_find_widget() manually constructs a prefixed widget name
> based on the provided DAPM context and compares it using strcmp(). This
> happens to work in most cases because callers usually know which DAPM
> context the target widget belongs to and pass in the matching DAPM
> context.

> -	if (prefix) {
> -		snprintf(prefixed_pin, sizeof(prefixed_pin), "%s %s",
> -			 prefix, pin);
> -		pin_name = prefixed_pin;
> -	} else {
> -		pin_name = pin;
> -	}
>  
>  	for_each_card_widgets(dapm->card, w) {
> -		if (!strcmp(w->name, pin_name)) {
> +		if (!snd_soc_dapm_widget_name_cmp(w, pin)) {
>  			if (w->dapm == dapm)
>  				return w;
>  			else

This means we can't use the prefix to disambiguate any more -
snd_soc_dapm_widget_name_cmp() will strip the prefix off.  We want the
prefix in contexts where the name is specified by the user since the
prefix is there to provide for disambiguation.  The prefix addition
logic is a bit weird and I'm not sure it makes sense, but the search
based on the fully specified name we got is something we want.

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