[PATCH v2 1/4] ASoC: cs42l43: Remove redundant semi-colon at end of function

[PATCH v2 1/4] ASoC: cs42l43: Remove redundant semi-colon at end of function

[Charles Keepax]

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
---

New since v1 of the series.

 sound/soc/codecs/cs42l43.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/soc/codecs/cs42l43.c b/sound/soc/codecs/cs42l43.c
index 92674314227c4..80825777048a6 100644
--- a/sound/soc/codecs/cs42l43.c
+++ b/sound/soc/codecs/cs42l43.c
@@ -608,7 +608,7 @@ static int cs42l43_sdw_hw_params(struct snd_pcm_substream *substream,
 		return ret;
 
 	return cs42l43_set_sample_rate(substream, params, dai);
-};
+}
 
 static const struct snd_soc_dai_ops cs42l43_sdw_ops = {
 	.startup	= cs42l43_startup,
-- 
2.39.2

[PATCH v2 2/4] ASoC: soc-component: Add new snd_soc_component_get_kcontrol() helper

[Charles Keepax]

Add a new helper function that returns a kcontrol by name, but will
factor in the components name_prefix, to handle situations where
multiple components are present with the same controls.

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
---

New since v1 of the series.

 include/sound/soc-component.h |  2 ++
 sound/soc/soc-component.c     | 16 ++++++++++++----
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/include/sound/soc-component.h b/include/sound/soc-component.h
index ceca69b46a821..61534ac0edd1d 100644
--- a/include/sound/soc-component.h
+++ b/include/sound/soc-component.h
@@ -462,6 +462,8 @@ int snd_soc_component_force_enable_pin_unlocked(
 	const char *pin);
 
 /* component controls */
+struct snd_kcontrol *snd_soc_component_get_kcontrol(struct snd_soc_component *component,
+						    const char * const ctl);
 int snd_soc_component_notify_control(struct snd_soc_component *component,
 				     const char * const ctl);
 
diff --git a/sound/soc/soc-component.c b/sound/soc/soc-component.c
index 4d7c2e3c929a9..1c0971823fb4d 100644
--- a/sound/soc/soc-component.c
+++ b/sound/soc/soc-component.c
@@ -236,11 +236,10 @@ int snd_soc_component_force_enable_pin_unlocked(
 }
 EXPORT_SYMBOL_GPL(snd_soc_component_force_enable_pin_unlocked);
 
-int snd_soc_component_notify_control(struct snd_soc_component *component,
-				     const char * const ctl)
+struct snd_kcontrol *snd_soc_component_get_kcontrol(struct snd_soc_component *component,
+						    const char * const ctl)
 {
 	char name[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
-	struct snd_kcontrol *kctl;
 
 	/* When updating, change also snd_soc_dapm_widget_name_cmp() */
 	if (component->name_prefix)
@@ -248,7 +247,16 @@ int snd_soc_component_notify_control(struct snd_soc_component *component,
 	else
 		snprintf(name, ARRAY_SIZE(name), "%s", ctl);
 
-	kctl = snd_soc_card_get_kcontrol(component->card, name);
+	return snd_soc_card_get_kcontrol(component->card, name);
+}
+EXPORT_SYMBOL_GPL(snd_soc_component_get_kcontrol);
+
+int snd_soc_component_notify_control(struct snd_soc_component *component,
+				     const char * const ctl)
+{
+	struct snd_kcontrol *kctl;
+
+	kctl = snd_soc_component_get_kcontrol(component, ctl);
 	if (!kctl)
 		return soc_component_ret(component, -EINVAL);
 
-- 
2.39.2

[PATCH v2 3/4] ASoC: cs35l45: Use new snd_soc_component_get_kcontrol() helper

[Charles Keepax]

No longer any need to hard code the addition of the name prefix, use the
new helper.

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
---

New since v1 of the series.

 sound/soc/codecs/cs35l45.c | 11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/sound/soc/codecs/cs35l45.c b/sound/soc/codecs/cs35l45.c
index 2392c6effed85..1fefdb80d758c 100644
--- a/sound/soc/codecs/cs35l45.c
+++ b/sound/soc/codecs/cs35l45.c
@@ -176,17 +176,10 @@ static int cs35l45_activate_ctl(struct snd_soc_component *component,
 	struct snd_kcontrol *kcontrol;
 	struct snd_kcontrol_volatile *vd;
 	unsigned int index_offset;
-	char name[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
 
-	if (component->name_prefix)
-		snprintf(name, SNDRV_CTL_ELEM_ID_NAME_MAXLEN, "%s %s",
-			 component->name_prefix, ctl_name);
-	else
-		snprintf(name, SNDRV_CTL_ELEM_ID_NAME_MAXLEN, "%s", ctl_name);
-
-	kcontrol = snd_soc_card_get_kcontrol_locked(component->card, name);
+	kcontrol = snd_soc_component_get_kcontrol_locked(component->card, ctl_name);
 	if (!kcontrol) {
-		dev_err(component->dev, "Can't find kcontrol %s\n", name);
+		dev_err(component->dev, "Can't find kcontrol %s\n", ctl_name);
 		return -EINVAL;
 	}
 
-- 
2.39.2

[PATCH v2 4/4] ASoC: cs42l43: Cache shutter IRQ control pointers

[Charles Keepax]

The microphone/speaker privacy shutter ALSA control handlers need to
call pm_runtime_resume, since the hardware needs to be powered up to
check the hardware state of the shutter. The IRQ handler for the
shutters also needs to notify the ALSA control to inform user-space
the shutters updated. However this leads to a mutex inversion,
between the sdw_dev_lock and the controls_rwsem.

To avoid this mutex inversion cache the kctl pointers before the IRQ
handler, which avoids the need to lookup the control and take the
controls_rwsem.

Suggested-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
---

Changes since v1:
 - Rather than delaying to a work queue, cache the control pointers to
   avoid looking them up in the IRQ handler.

 sound/soc/codecs/cs42l43.c | 71 +++++++++++++++++++++++++++++---------
 sound/soc/codecs/cs42l43.h |  2 ++
 2 files changed, 56 insertions(+), 17 deletions(-)

diff --git a/sound/soc/codecs/cs42l43.c b/sound/soc/codecs/cs42l43.c
index 80825777048a6..4771f235b1cc4 100644
--- a/sound/soc/codecs/cs42l43.c
+++ b/sound/soc/codecs/cs42l43.c
@@ -7,6 +7,7 @@
 
 #include <linux/bitops.h>
 #include <linux/bits.h>
+#include <linux/build_bug.h>
 #include <linux/clk.h>
 #include <linux/device.h>
 #include <linux/err.h>
@@ -252,24 +253,20 @@ CS42L43_IRQ_COMPLETE(load_detect)
 static irqreturn_t cs42l43_mic_shutter(int irq, void *data)
 {
 	struct cs42l43_codec *priv = data;
-	static const char * const controls[] = {
-		"Decimator 1 Switch",
-		"Decimator 2 Switch",
-		"Decimator 3 Switch",
-		"Decimator 4 Switch",
-	};
-	int i, ret;
+	struct snd_soc_component *component = priv->component;
+	int i;
 
 	dev_dbg(priv->dev, "Microphone shutter changed\n");
 
-	if (!priv->component)
+	if (!component)
 		return IRQ_NONE;
 
-	for (i = 0; i < ARRAY_SIZE(controls); i++) {
-		ret = snd_soc_component_notify_control(priv->component,
-						       controls[i]);
-		if (ret)
+	for (i = 1; i < ARRAY_SIZE(priv->kctl); i++) {
+		if (!priv->kctl[i])
 			return IRQ_NONE;
+
+		snd_ctl_notify(component->card->snd_card,
+			       SNDRV_CTL_EVENT_MASK_VALUE, &priv->kctl[i]->id);
 	}
 
 	return IRQ_HANDLED;
@@ -278,18 +275,19 @@ static irqreturn_t cs42l43_mic_shutter(int irq, void *data)
 static irqreturn_t cs42l43_spk_shutter(int irq, void *data)
 {
 	struct cs42l43_codec *priv = data;
-	int ret;
+	struct snd_soc_component *component = priv->component;
 
 	dev_dbg(priv->dev, "Speaker shutter changed\n");
 
-	if (!priv->component)
+	if (!component)
 		return IRQ_NONE;
 
-	ret = snd_soc_component_notify_control(priv->component,
-					       "Speaker Digital Switch");
-	if (ret)
+	if (!priv->kctl[0])
 		return IRQ_NONE;
 
+	snd_ctl_notify(component->card->snd_card,
+		       SNDRV_CTL_EVENT_MASK_VALUE, &priv->kctl[0]->id);
+
 	return IRQ_HANDLED;
 }
 
@@ -610,7 +608,46 @@ static int cs42l43_sdw_hw_params(struct snd_pcm_substream *substream,
 	return cs42l43_set_sample_rate(substream, params, dai);
 }
 
+static int cs42l43_dai_probe(struct snd_soc_dai *dai)
+{
+	struct snd_soc_component *component = dai->component;
+	struct cs42l43_codec *priv = snd_soc_component_get_drvdata(component);
+	static const char * const controls[] = {
+		"Speaker Digital Switch",
+		"Decimator 1 Switch",
+		"Decimator 2 Switch",
+		"Decimator 3 Switch",
+		"Decimator 4 Switch",
+	};
+	int i;
+
+	static_assert(ARRAY_SIZE(controls) == ARRAY_SIZE(priv->kctl));
+
+	for (i = 0; i < ARRAY_SIZE(controls); i++) {
+		if (priv->kctl[i])
+			continue;
+
+		priv->kctl[i] = snd_soc_component_get_kcontrol(component, controls[i]);
+	}
+
+	return 0;
+}
+
+static int cs42l43_dai_remove(struct snd_soc_dai *dai)
+{
+	struct snd_soc_component *component = dai->component;
+	struct cs42l43_codec *priv = snd_soc_component_get_drvdata(component);
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(priv->kctl); i++)
+		priv->kctl[i] = NULL;
+
+	return 0;
+}
+
 static const struct snd_soc_dai_ops cs42l43_sdw_ops = {
+	.probe		= cs42l43_dai_probe,
+	.remove		= cs42l43_dai_remove,
 	.startup	= cs42l43_startup,
 	.set_stream	= cs42l43_sdw_set_stream,
 	.hw_params	= cs42l43_sdw_hw_params,
diff --git a/sound/soc/codecs/cs42l43.h b/sound/soc/codecs/cs42l43.h
index 9924c13e1eb53..9c144e129535f 100644
--- a/sound/soc/codecs/cs42l43.h
+++ b/sound/soc/codecs/cs42l43.h
@@ -100,6 +100,8 @@ struct cs42l43_codec {
 	struct delayed_work hp_ilimit_clear_work;
 	bool hp_ilimited;
 	int hp_ilimit_count;
+
+	struct snd_kcontrol *kctl[5];
 };
 
 #if IS_REACHABLE(CONFIG_SND_SOC_CS42L43_SDW)
-- 
2.39.2

Re: [PATCH v2 4/4] ASoC: cs42l43: Cache shutter IRQ control pointers

[Charles Keepax]

On Wed, Jul 31, 2024 at 02:39:05PM +0100, Charles Keepax wrote:
> The microphone/speaker privacy shutter ALSA control handlers need to
> call pm_runtime_resume, since the hardware needs to be powered up to
> check the hardware state of the shutter. The IRQ handler for the
> shutters also needs to notify the ALSA control to inform user-space
> the shutters updated. However this leads to a mutex inversion,
> between the sdw_dev_lock and the controls_rwsem.
> 
> To avoid this mutex inversion cache the kctl pointers before the IRQ
> handler, which avoids the need to lookup the control and take the
> controls_rwsem.
> 
> Suggested-by: Jaroslav Kysela <perex@perex.cz>
> Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
> ---
>  static const struct snd_soc_dai_ops cs42l43_sdw_ops = {
> +	.probe		= cs42l43_dai_probe,
> +	.remove		= cs42l43_dai_remove,
>  	.startup	= cs42l43_startup,
>  	.set_stream	= cs42l43_sdw_set_stream,
>  	.hw_params	= cs42l43_sdw_hw_params,

Actually probably makes slightly more sense to use the ASP ops
for the caching the control names, I will leave the patches
overnight for any other comments then send a v3 tomorrow.

Thanks,
Charles