[PATCH] ASoC: da7219: Improve the IRQ process to increase the stability

[PATCH] ASoC: da7219: Improve the IRQ process to increase the stability

[David Rau]

Remove the sleep control in IRQ thread
and create an individual task to handel it for Jack plug in event.

This commit improves the control of ground switches in the AAD IRQ.

Signed-off-by: David Rau <David.Rau.opensource@dm.renesas.com>
---
 sound/soc/codecs/da7219-aad.c | 41 +++++++++++++++++++++++++++++------
 sound/soc/codecs/da7219-aad.h |  4 ++++
 2 files changed, 38 insertions(+), 7 deletions(-)

diff --git a/sound/soc/codecs/da7219-aad.c b/sound/soc/codecs/da7219-aad.c
index c55b033d89da..4a4f09f924bc 100644
--- a/sound/soc/codecs/da7219-aad.c
+++ b/sound/soc/codecs/da7219-aad.c
@@ -339,11 +339,39 @@ static void da7219_aad_hptest_work(struct work_struct *work)
 				    SND_JACK_HEADSET | SND_JACK_LINEOUT);
 }
 
+static void da7219_aad_jack_det_work(struct work_struct *work)
+{
+	struct da7219_aad_priv *da7219_aad =
+		container_of(work, struct da7219_aad_priv, jack_det_work);
+	struct snd_soc_component *component = da7219_aad->component;
+	u8 srm_st;
+
+	mutex_lock(&da7219_aad->jack_det_mutex);
+
+	srm_st = snd_soc_component_read(component, DA7219_PLL_SRM_STS) & DA7219_PLL_SRM_STS_MCLK;
+	msleep(da7219_aad->gnd_switch_delay * ((srm_st == 0x0) ? 2 : 1) - 4);
+	/* Enable ground switch */
+	snd_soc_component_update_bits(component, 0xFB, 0x01, 0x01);
+
+	mutex_unlock(&da7219_aad->jack_det_mutex);
+}
+
 
 /*
  * IRQ
  */
 
+static irqreturn_t da7219_aad_pre_irq_thread(int irq, void *data)
+{
+
+	struct da7219_aad_priv *da7219_aad = data;
+
+	if (!da7219_aad->jack_inserted)
+		schedule_work(&da7219_aad->jack_det_work);
+
+	return IRQ_WAKE_THREAD;
+}
+
 static irqreturn_t da7219_aad_irq_thread(int irq, void *data)
 {
 	struct da7219_aad_priv *da7219_aad = data;
@@ -351,14 +379,9 @@ static irqreturn_t da7219_aad_irq_thread(int irq, void *data)
 	struct snd_soc_dapm_context *dapm = snd_soc_component_get_dapm(component);
 	struct da7219_priv *da7219 = snd_soc_component_get_drvdata(component);
 	u8 events[DA7219_AAD_IRQ_REG_MAX];
-	u8 statusa, srm_st;
+	u8 statusa;
 	int i, report = 0, mask = 0;
 
-	srm_st = snd_soc_component_read(component, DA7219_PLL_SRM_STS) & DA7219_PLL_SRM_STS_MCLK;
-	msleep(da7219_aad->gnd_switch_delay * ((srm_st == 0x0) ? 2 : 1) - 4);
-	/* Enable ground switch */
-	snd_soc_component_update_bits(component, 0xFB, 0x01, 0x01);
-
 	/* Read current IRQ events */
 	regmap_bulk_read(da7219->regmap, DA7219_ACCDET_IRQ_EVENT_A,
 			 events, DA7219_AAD_IRQ_REG_MAX);
@@ -377,6 +400,9 @@ static irqreturn_t da7219_aad_irq_thread(int irq, void *data)
 		events[DA7219_AAD_IRQ_REG_A], events[DA7219_AAD_IRQ_REG_B],
 		statusa);
 
+	if (!da7219_aad->jack_inserted)
+		cancel_work_sync(&da7219_aad->jack_det_work);
+
 	if (statusa & DA7219_JACK_INSERTION_STS_MASK) {
 		/* Jack Insertion */
 		if (events[DA7219_AAD_IRQ_REG_A] &
@@ -940,8 +966,9 @@ int da7219_aad_init(struct snd_soc_component *component)
 
 	INIT_WORK(&da7219_aad->btn_det_work, da7219_aad_btn_det_work);
 	INIT_WORK(&da7219_aad->hptest_work, da7219_aad_hptest_work);
+	INIT_WORK(&da7219_aad->jack_det_work, da7219_aad_jack_det_work);
 
-	ret = request_threaded_irq(da7219_aad->irq, NULL,
+	ret = request_threaded_irq(da7219_aad->irq, da7219_aad_pre_irq_thread,
 				   da7219_aad_irq_thread,
 				   IRQF_TRIGGER_LOW | IRQF_ONESHOT,
 				   "da7219-aad", da7219_aad);
diff --git a/sound/soc/codecs/da7219-aad.h b/sound/soc/codecs/da7219-aad.h
index 21fdf53095cc..be87ee47edde 100644
--- a/sound/soc/codecs/da7219-aad.h
+++ b/sound/soc/codecs/da7219-aad.h
@@ -11,6 +11,7 @@
 #define __DA7219_AAD_H
 
 #include <linux/timer.h>
+#include <linux/mutex.h>
 #include <sound/soc.h>
 #include <sound/jack.h>
 #include <sound/da7219-aad.h>
@@ -196,6 +197,9 @@ struct da7219_aad_priv {
 
 	struct work_struct btn_det_work;
 	struct work_struct hptest_work;
+	struct work_struct jack_det_work;
+
+	struct mutex  jack_det_mutex;
 
 	struct snd_soc_jack *jack;
 	bool micbias_resume_enable;
-- 
2.17.1

Re: [PATCH] ASoC: da7219: Improve the IRQ process to increase the stability

[Mark Brown]

[-- Attachment #1: Type: text/plain, Size: 4567 bytes --]

On Wed, Feb 15, 2023 at 10:10:45AM +0000, David Rau wrote:
> Remove the sleep control in IRQ thread
> and create an individual task to handel it for Jack plug in event.
> 
> This commit improves the control of ground switches in the AAD IRQ.

Copying in Guenter given the issues he raised with this, not
deleting context for his benefit.  It looks like this should
avoid the issues with the interrupt appearing locked up.

> Signed-off-by: David Rau <David.Rau.opensource@dm.renesas.com>
> ---
>  sound/soc/codecs/da7219-aad.c | 41 +++++++++++++++++++++++++++++------
>  sound/soc/codecs/da7219-aad.h |  4 ++++
>  2 files changed, 38 insertions(+), 7 deletions(-)
> 
> diff --git a/sound/soc/codecs/da7219-aad.c b/sound/soc/codecs/da7219-aad.c
> index c55b033d89da..4a4f09f924bc 100644
> --- a/sound/soc/codecs/da7219-aad.c
> +++ b/sound/soc/codecs/da7219-aad.c
> @@ -339,11 +339,39 @@ static void da7219_aad_hptest_work(struct work_struct *work)
>  				    SND_JACK_HEADSET | SND_JACK_LINEOUT);
>  }
>  
> +static void da7219_aad_jack_det_work(struct work_struct *work)
> +{
> +	struct da7219_aad_priv *da7219_aad =
> +		container_of(work, struct da7219_aad_priv, jack_det_work);
> +	struct snd_soc_component *component = da7219_aad->component;
> +	u8 srm_st;
> +
> +	mutex_lock(&da7219_aad->jack_det_mutex);
> +
> +	srm_st = snd_soc_component_read(component, DA7219_PLL_SRM_STS) & DA7219_PLL_SRM_STS_MCLK;
> +	msleep(da7219_aad->gnd_switch_delay * ((srm_st == 0x0) ? 2 : 1) - 4);
> +	/* Enable ground switch */
> +	snd_soc_component_update_bits(component, 0xFB, 0x01, 0x01);
> +
> +	mutex_unlock(&da7219_aad->jack_det_mutex);

This mutex is only held by this work function - is it needed?

> +}
> +
>  
>  /*
>   * IRQ
>   */
>  
> +static irqreturn_t da7219_aad_pre_irq_thread(int irq, void *data)
> +{
> +
> +	struct da7219_aad_priv *da7219_aad = data;
> +
> +	if (!da7219_aad->jack_inserted)
> +		schedule_work(&da7219_aad->jack_det_work);
> +
> +	return IRQ_WAKE_THREAD;
> +}
> +
>  static irqreturn_t da7219_aad_irq_thread(int irq, void *data)
>  {
>  	struct da7219_aad_priv *da7219_aad = data;
> @@ -351,14 +379,9 @@ static irqreturn_t da7219_aad_irq_thread(int irq, void *data)
>  	struct snd_soc_dapm_context *dapm = snd_soc_component_get_dapm(component);
>  	struct da7219_priv *da7219 = snd_soc_component_get_drvdata(component);
>  	u8 events[DA7219_AAD_IRQ_REG_MAX];
> -	u8 statusa, srm_st;
> +	u8 statusa;
>  	int i, report = 0, mask = 0;
>  
> -	srm_st = snd_soc_component_read(component, DA7219_PLL_SRM_STS) & DA7219_PLL_SRM_STS_MCLK;
> -	msleep(da7219_aad->gnd_switch_delay * ((srm_st == 0x0) ? 2 : 1) - 4);
> -	/* Enable ground switch */
> -	snd_soc_component_update_bits(component, 0xFB, 0x01, 0x01);
> -
>  	/* Read current IRQ events */
>  	regmap_bulk_read(da7219->regmap, DA7219_ACCDET_IRQ_EVENT_A,
>  			 events, DA7219_AAD_IRQ_REG_MAX);
> @@ -377,6 +400,9 @@ static irqreturn_t da7219_aad_irq_thread(int irq, void *data)
>  		events[DA7219_AAD_IRQ_REG_A], events[DA7219_AAD_IRQ_REG_B],
>  		statusa);
>  
> +	if (!da7219_aad->jack_inserted)
> +		cancel_work_sync(&da7219_aad->jack_det_work);
> +
>  	if (statusa & DA7219_JACK_INSERTION_STS_MASK) {
>  		/* Jack Insertion */
>  		if (events[DA7219_AAD_IRQ_REG_A] &
> @@ -940,8 +966,9 @@ int da7219_aad_init(struct snd_soc_component *component)
>  
>  	INIT_WORK(&da7219_aad->btn_det_work, da7219_aad_btn_det_work);
>  	INIT_WORK(&da7219_aad->hptest_work, da7219_aad_hptest_work);
> +	INIT_WORK(&da7219_aad->jack_det_work, da7219_aad_jack_det_work);
>  
> -	ret = request_threaded_irq(da7219_aad->irq, NULL,
> +	ret = request_threaded_irq(da7219_aad->irq, da7219_aad_pre_irq_thread,
>  				   da7219_aad_irq_thread,
>  				   IRQF_TRIGGER_LOW | IRQF_ONESHOT,
>  				   "da7219-aad", da7219_aad);
> diff --git a/sound/soc/codecs/da7219-aad.h b/sound/soc/codecs/da7219-aad.h
> index 21fdf53095cc..be87ee47edde 100644
> --- a/sound/soc/codecs/da7219-aad.h
> +++ b/sound/soc/codecs/da7219-aad.h
> @@ -11,6 +11,7 @@
>  #define __DA7219_AAD_H
>  
>  #include <linux/timer.h>
> +#include <linux/mutex.h>
>  #include <sound/soc.h>
>  #include <sound/jack.h>
>  #include <sound/da7219-aad.h>
> @@ -196,6 +197,9 @@ struct da7219_aad_priv {
>  
>  	struct work_struct btn_det_work;
>  	struct work_struct hptest_work;
> +	struct work_struct jack_det_work;
> +
> +	struct mutex  jack_det_mutex;
>  
>  	struct snd_soc_jack *jack;
>  	bool micbias_resume_enable;
> -- 
> 2.17.1
> 

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

Re: [PATCH] ASoC: da7219: Improve the IRQ process to increase the stability

[Guenter Roeck]

On Wed, Feb 15, 2023 at 5:10 AM Mark Brown <broonie@kernel.org> wrote:
>
> On Wed, Feb 15, 2023 at 10:10:45AM +0000, David Rau wrote:
> > Remove the sleep control in IRQ thread
> > and create an individual task to handel it for Jack plug in event.

handle

> >
> > This commit improves the control of ground switches in the AAD IRQ.
>
> Copying in Guenter given the issues he raised with this, not
> deleting context for his benefit.  It looks like this should
> avoid the issues with the interrupt appearing locked up.
>

It should since it limits the delay to cases where jack_inserted is
false, but on the other side it hides the delay in an odd way.

Sequence for an insertion interrupt:

- da7219_aad_pre_irq_thread() schedules the worker, which presumably
starts to run immediately and goes to sleep
- da7219_aad_irq_thread() calls cancel_work_sync() and thus
effectively waits until the worker wakes up and sets the ground switch

On top of that, it now reads the interrupt status before calling
cancel_work_sync(), meaning additional interrupts received while
waiting for the thread to wake up are not handled by the first
interrupt.

Effectively this seems to be quite similar to moving the conditional
sleep to the place where cancel_work_sync() is called. I would assume
that will fix the problem (after all, the msleep() is no longer called
unconditionally), but I don't see the benefit of introducing a worker
to do that. Also, since there is no guarantee that the worker actually
started by the time cancel_work_sync() is called, I would suspect that
it may result in unexpected behavior if the worker has not started by
that time, which I would assume can happen if the system is heavily
loaded. It also makes the use of the ground switch (i.e., when to set
and when to drop it) even more of a mystery than it is right now.

Having said that, I don't really know or understand the code, so maybe
this all makes sense and my feedback should be ignored.

Guenter

> > Signed-off-by: David Rau <David.Rau.opensource@dm.renesas.com>
> > ---
> >  sound/soc/codecs/da7219-aad.c | 41 +++++++++++++++++++++++++++++------
> >  sound/soc/codecs/da7219-aad.h |  4 ++++
> >  2 files changed, 38 insertions(+), 7 deletions(-)
> >
> > diff --git a/sound/soc/codecs/da7219-aad.c b/sound/soc/codecs/da7219-aad.c
> > index c55b033d89da..4a4f09f924bc 100644
> > --- a/sound/soc/codecs/da7219-aad.c
> > +++ b/sound/soc/codecs/da7219-aad.c
> > @@ -339,11 +339,39 @@ static void da7219_aad_hptest_work(struct work_struct *work)
> >                                   SND_JACK_HEADSET | SND_JACK_LINEOUT);
> >  }
> >
> > +static void da7219_aad_jack_det_work(struct work_struct *work)
> > +{
> > +     struct da7219_aad_priv *da7219_aad =
> > +             container_of(work, struct da7219_aad_priv, jack_det_work);
> > +     struct snd_soc_component *component = da7219_aad->component;
> > +     u8 srm_st;
> > +
> > +     mutex_lock(&da7219_aad->jack_det_mutex);
> > +
> > +     srm_st = snd_soc_component_read(component, DA7219_PLL_SRM_STS) & DA7219_PLL_SRM_STS_MCLK;
> > +     msleep(da7219_aad->gnd_switch_delay * ((srm_st == 0x0) ? 2 : 1) - 4);
> > +     /* Enable ground switch */
> > +     snd_soc_component_update_bits(component, 0xFB, 0x01, 0x01);
> > +
> > +     mutex_unlock(&da7219_aad->jack_det_mutex);
>
> This mutex is only held by this work function - is it needed?
>
> > +}
> > +
> >
> >  /*
> >   * IRQ
> >   */
> >
> > +static irqreturn_t da7219_aad_pre_irq_thread(int irq, void *data)
> > +{
> > +
> > +     struct da7219_aad_priv *da7219_aad = data;
> > +
> > +     if (!da7219_aad->jack_inserted)
> > +             schedule_work(&da7219_aad->jack_det_work);
> > +
> > +     return IRQ_WAKE_THREAD;
> > +}
> > +
> >  static irqreturn_t da7219_aad_irq_thread(int irq, void *data)
> >  {
> >       struct da7219_aad_priv *da7219_aad = data;
> > @@ -351,14 +379,9 @@ static irqreturn_t da7219_aad_irq_thread(int irq, void *data)
> >       struct snd_soc_dapm_context *dapm = snd_soc_component_get_dapm(component);
> >       struct da7219_priv *da7219 = snd_soc_component_get_drvdata(component);
> >       u8 events[DA7219_AAD_IRQ_REG_MAX];
> > -     u8 statusa, srm_st;
> > +     u8 statusa;
> >       int i, report = 0, mask = 0;
> >
> > -     srm_st = snd_soc_component_read(component, DA7219_PLL_SRM_STS) & DA7219_PLL_SRM_STS_MCLK;
> > -     msleep(da7219_aad->gnd_switch_delay * ((srm_st == 0x0) ? 2 : 1) - 4);
> > -     /* Enable ground switch */
> > -     snd_soc_component_update_bits(component, 0xFB, 0x01, 0x01);
> > -
> >       /* Read current IRQ events */
> >       regmap_bulk_read(da7219->regmap, DA7219_ACCDET_IRQ_EVENT_A,
> >                        events, DA7219_AAD_IRQ_REG_MAX);
> > @@ -377,6 +400,9 @@ static irqreturn_t da7219_aad_irq_thread(int irq, void *data)
> >               events[DA7219_AAD_IRQ_REG_A], events[DA7219_AAD_IRQ_REG_B],
> >               statusa);
> >
> > +     if (!da7219_aad->jack_inserted)
> > +             cancel_work_sync(&da7219_aad->jack_det_work);
> > +
> >       if (statusa & DA7219_JACK_INSERTION_STS_MASK) {
> >               /* Jack Insertion */
> >               if (events[DA7219_AAD_IRQ_REG_A] &
> > @@ -940,8 +966,9 @@ int da7219_aad_init(struct snd_soc_component *component)
> >
> >       INIT_WORK(&da7219_aad->btn_det_work, da7219_aad_btn_det_work);
> >       INIT_WORK(&da7219_aad->hptest_work, da7219_aad_hptest_work);
> > +     INIT_WORK(&da7219_aad->jack_det_work, da7219_aad_jack_det_work);
> >
> > -     ret = request_threaded_irq(da7219_aad->irq, NULL,
> > +     ret = request_threaded_irq(da7219_aad->irq, da7219_aad_pre_irq_thread,
> >                                  da7219_aad_irq_thread,
> >                                  IRQF_TRIGGER_LOW | IRQF_ONESHOT,
> >                                  "da7219-aad", da7219_aad);
> > diff --git a/sound/soc/codecs/da7219-aad.h b/sound/soc/codecs/da7219-aad.h
> > index 21fdf53095cc..be87ee47edde 100644
> > --- a/sound/soc/codecs/da7219-aad.h
> > +++ b/sound/soc/codecs/da7219-aad.h
> > @@ -11,6 +11,7 @@
> >  #define __DA7219_AAD_H
> >
> >  #include <linux/timer.h>
> > +#include <linux/mutex.h>
> >  #include <sound/soc.h>
> >  #include <sound/jack.h>
> >  #include <sound/da7219-aad.h>
> > @@ -196,6 +197,9 @@ struct da7219_aad_priv {
> >
> >       struct work_struct btn_det_work;
> >       struct work_struct hptest_work;
> > +     struct work_struct jack_det_work;
> > +
> > +     struct mutex  jack_det_mutex;
> >
> >       struct snd_soc_jack *jack;
> >       bool micbias_resume_enable;
> > --
> > 2.17.1
> >

Re: [PATCH] ASoC: da7219: Improve the IRQ process to increase the stability

[Mark Brown]

[-- Attachment #1: Type: text/plain, Size: 1590 bytes --]

On Wed, Feb 15, 2023 at 08:06:35AM -0800, Guenter Roeck wrote:
> On Wed, Feb 15, 2023 at 5:10 AM Mark Brown <broonie@kernel.org> wrote:

> > Copying in Guenter given the issues he raised with this, not
> > deleting context for his benefit.  It looks like this should
> > avoid the issues with the interrupt appearing locked up.

> It should since it limits the delay to cases where jack_inserted is
> false, but on the other side it hides the delay in an odd way.
> 
...

> Effectively this seems to be quite similar to moving the conditional
> sleep to the place where cancel_work_sync() is called. I would assume
> that will fix the problem (after all, the msleep() is no longer called
> unconditionally), but I don't see the benefit of introducing a worker
> to do that. Also, since there is no guarantee that the worker actually
> started by the time cancel_work_sync() is called, I would suspect that
> it may result in unexpected behavior if the worker has not started by
> that time, which I would assume can happen if the system is heavily
> loaded. It also makes the use of the ground switch (i.e., when to set
> and when to drop it) even more of a mystery than it is right now.

> Having said that, I don't really know or understand the code, so maybe
> this all makes sense and my feedback should be ignored.

Yes, I would certainly welcome more clarity especially around the
ground switch.  OTOH it does seem like an improvement over the
current situation so I think I'll go ahead and apply it for now,
hopefully it can be improved upon in future.

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

Re: [PATCH] ASoC: da7219: Improve the IRQ process to increase the stability

[Mark Brown]

On Wed, 15 Feb 2023 10:10:45 +0000, David Rau wrote:
> Remove the sleep control in IRQ thread
> and create an individual task to handel it for Jack plug in event.
> 
> This commit improves the control of ground switches in the AAD IRQ.
> 
> 

Applied to

   broonie/sound.git for-next

Thanks!

[1/1] ASoC: da7219: Improve the IRQ process to increase the stability
      commit: 7fde88eda855952766a74026c181c6270b3392fc

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark