diff mbox series

[v2,3/4] ALSA: hda: Separate runtime and system suspend

Message ID 20201027054001.1800-4-kai.heng.feng@canonical.com (mailing list archive)
State New, archived
Headers show
Series HDA controller and PM cleanups | expand

Commit Message

Kai-Heng Feng Oct. 27, 2020, 5:40 a.m. UTC
Both pm_runtime_force_suspend() and pm_runtime_force_resume() have
some implicit checks, so it can make code flow more straightfoward if we
separate runtime and systemd suspend callbacks.

High Definition Audio Specification, 4.5.9.3 Codec Wake From System S3
states that codec can wake the system up from S3 if WAKEEN is toggled.
Since HDA controller has different wakeup settings for runtime and
system susend, we also need to explicitly disable direct-complete which
can be enabled automatically by PCI core. In addition to that, avoid
waking up codec if runtime resume is for system suspend, to not break
direct-complete for codecs.

While at it, also remove AZX_DCAPS_SUSPEND_SPURIOUS_WAKEUP, as the
original bug commit a6630529aecb ("ALSA: hda: Workaround for spurious
wakeups on some Intel platforms") solves doesn't happen with this
patch.

Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
---
v2:
 - Make sure WAKEEN is disabled for system suspend.
 - Avoid waking up codec if runtime resume is for system suspend

 sound/pci/hda/hda_controller.h |  3 +-
 sound/pci/hda/hda_intel.c      | 61 +++++++++++++++++++---------------
 2 files changed, 37 insertions(+), 27 deletions(-)

Comments

Takashi Iwai Oct. 27, 2020, 7:46 a.m. UTC | #1
On Tue, 27 Oct 2020 06:40:00 +0100,
Kai-Heng Feng wrote:
> @@ -1002,7 +1001,8 @@ static void __azx_runtime_resume(struct azx *chip, bool from_rt)
>  	azx_init_pci(chip);
>  	hda_intel_init_chip(chip, true);
>  
> -	if (from_rt) {
> +	/* Avoid codec resume if runtime resume is for system suspend */
> +	if (from_rt && !chip->prepared) {

The check of chip->prepared is superfluous here.  Its check should be
applied rather at setting WAKEEN, namely...

> @@ -1103,10 +1115,8 @@ static int azx_runtime_suspend(struct device *dev)
>  	chip = card->private_data;
>  
>  	/* enable controller wake up event */
> -	if (snd_power_get_state(card) == SNDRV_CTL_POWER_D0) {
> -		azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) |
> -			   STATESTS_INT_MASK);
> -	}
> +	azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) |
> +		   STATESTS_INT_MASK);

... here we should have the check of chip->prepared, and set WAKEEN
only when it's false.  Otherwise WAKEEN is set up for the system
suspend, and it might lead to spurious wakeups.  (IOW, checking the
flag at resume doesn't help for preventing the spurious wakeup :)


thanks,

Takashi
Takashi Iwai Oct. 27, 2020, 8:12 a.m. UTC | #2
On Tue, 27 Oct 2020 08:46:05 +0100,
Takashi Iwai wrote:
> > @@ -1103,10 +1115,8 @@ static int azx_runtime_suspend(struct device *dev)
> >  	chip = card->private_data;
> >  
> >  	/* enable controller wake up event */
> > -	if (snd_power_get_state(card) == SNDRV_CTL_POWER_D0) {
> > -		azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) |
> > -			   STATESTS_INT_MASK);
> > -	}
> > +	azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) |
> > +		   STATESTS_INT_MASK);
> 
> ... here we should have the check of chip->prepared, and set WAKEEN
> only when it's false.  Otherwise WAKEEN is set up for the system
> suspend, and it might lead to spurious wakeups.  (IOW, checking the
> flag at resume doesn't help for preventing the spurious wakeup :)

Scratch my comment above; it's the code path only for the runtime
suspend in your new code, then this cleanup makes sense.


thanks,

Takashi
Takashi Iwai Oct. 27, 2020, 8:15 a.m. UTC | #3
On Tue, 27 Oct 2020 09:12:07 +0100,
Takashi Iwai wrote:
> 
> On Tue, 27 Oct 2020 08:46:05 +0100,
> Takashi Iwai wrote:
> > > @@ -1103,10 +1115,8 @@ static int azx_runtime_suspend(struct device *dev)
> > >  	chip = card->private_data;
> > >  
> > >  	/* enable controller wake up event */
> > > -	if (snd_power_get_state(card) == SNDRV_CTL_POWER_D0) {
> > > -		azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) |
> > > -			   STATESTS_INT_MASK);
> > > -	}
> > > +	azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) |
> > > +		   STATESTS_INT_MASK);
> > 
> > ... here we should have the check of chip->prepared, and set WAKEEN
> > only when it's false.  Otherwise WAKEEN is set up for the system
> > suspend, and it might lead to spurious wakeups.  (IOW, checking the
> > flag at resume doesn't help for preventing the spurious wakeup :)
> 
> Scratch my comment above; it's the code path only for the runtime
> suspend in your new code, then this cleanup makes sense.

Also, as one more cleanup: from_rt in __azx_runtime_resume() can be
replaced with !chip->prepared flag, so the extra argument can be
dropped.


Takashi
Kai-Heng Feng Oct. 27, 2020, 8:24 a.m. UTC | #4
> On Oct 27, 2020, at 16:15, Takashi Iwai <tiwai@suse.de> wrote:
> 
> On Tue, 27 Oct 2020 09:12:07 +0100,
> Takashi Iwai wrote:
>> 
>> On Tue, 27 Oct 2020 08:46:05 +0100,
>> Takashi Iwai wrote:
>>>> @@ -1103,10 +1115,8 @@ static int azx_runtime_suspend(struct device *dev)
>>>> 	chip = card->private_data;
>>>> 
>>>> 	/* enable controller wake up event */
>>>> -	if (snd_power_get_state(card) == SNDRV_CTL_POWER_D0) {
>>>> -		azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) |
>>>> -			   STATESTS_INT_MASK);
>>>> -	}
>>>> +	azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) |
>>>> +		   STATESTS_INT_MASK);
>>> 
>>> ... here we should have the check of chip->prepared, and set WAKEEN
>>> only when it's false.  Otherwise WAKEEN is set up for the system
>>> suspend, and it might lead to spurious wakeups.  (IOW, checking the
>>> flag at resume doesn't help for preventing the spurious wakeup :)
>> 
>> Scratch my comment above; it's the code path only for the runtime
>> suspend in your new code, then this cleanup makes sense.
> 
> Also, as one more cleanup: from_rt in __azx_runtime_resume() can be
> replaced with !chip->prepared flag, so the extra argument can be
> dropped.

Ok, will send v3 to address it.

Kai-Heng

> 
> 
> Takashi
Kai Vehmanen Oct. 27, 2020, 11:38 a.m. UTC | #5
Hi,

thanks, this looks like a good improvement! Some minor notes:

On Tue, 27 Oct 2020, Kai-Heng Feng wrote:

> Both pm_runtime_force_suspend() and pm_runtime_force_resume() have
> some implicit checks, so it can make code flow more straightfoward if we
> separate runtime and systemd suspend callbacks.

straightforward -> straightforward

and systemd? Maybe just "system suspend"? :)

> While at it, also remove AZX_DCAPS_SUSPEND_SPURIOUS_WAKEUP, as the
> original bug commit a6630529aecb ("ALSA: hda: Workaround for spurious
> wakeups on some Intel platforms") solves doesn't happen with this
> patch.

Hmm, so this was gone already with the v1 version (so not related to 
programming the WAKEEN when going to system suspend)?

> @@ -143,6 +143,7 @@ struct azx {
>  	unsigned int align_buffer_size:1;
>  	unsigned int region_requested:1;
>  	unsigned int disabled:1; /* disabled by vga_switcheroo */
> +	unsigned int prepared:1;

I wonder if "pm_prepared" would be better as ALSA API has a prepare method 
as well and this is not related. OTOH, if ok to Takashi, ok for me as 
well. 

> +	azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) &
> +		   ~STATESTS_INT_MASK);

This would fit to one line now. 

Br, Kai
Kai-Heng Feng Oct. 27, 2020, 12:04 p.m. UTC | #6
Hi Kai,

> On Oct 27, 2020, at 19:38, Kai Vehmanen <kai.vehmanen@linux.intel.com> wrote:
> 
> Hi,
> 
> thanks, this looks like a good improvement! Some minor notes:
> 
> On Tue, 27 Oct 2020, Kai-Heng Feng wrote:
> 
>> Both pm_runtime_force_suspend() and pm_runtime_force_resume() have
>> some implicit checks, so it can make code flow more straightfoward if we
>> separate runtime and systemd suspend callbacks.
> 
> straightforward -> straightforward
> 
> and systemd? Maybe just "system suspend"? :)

Typos :)
Will update them in v3.

> 
>> While at it, also remove AZX_DCAPS_SUSPEND_SPURIOUS_WAKEUP, as the
>> original bug commit a6630529aecb ("ALSA: hda: Workaround for spurious
>> wakeups on some Intel platforms") solves doesn't happen with this
>> patch.
> 
> Hmm, so this was gone already with the v1 version (so not related to 
> programming the WAKEEN when going to system suspend)?

Yes, I was worried that this cleanup may regress the user again.

> 
>> @@ -143,6 +143,7 @@ struct azx {
>> 	unsigned int align_buffer_size:1;
>> 	unsigned int region_requested:1;
>> 	unsigned int disabled:1; /* disabled by vga_switcheroo */
>> +	unsigned int prepared:1;
> 
> I wonder if "pm_prepared" would be better as ALSA API has a prepare method 
> as well and this is not related. OTOH, if ok to Takashi, ok for me as 
> well. 

Sure, I think we should use different terms.

> 
>> +	azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) &
>> +		   ~STATESTS_INT_MASK);
> 
> This would fit to one line now. 

Ok, will concat the lines.

Kai-Heng

> 
> Br, Kai
diff mbox series

Patch

diff --git a/sound/pci/hda/hda_controller.h b/sound/pci/hda/hda_controller.h
index be63ead8161f..7176ef8170ba 100644
--- a/sound/pci/hda/hda_controller.h
+++ b/sound/pci/hda/hda_controller.h
@@ -41,7 +41,7 @@ 
 /* 24 unused */
 #define AZX_DCAPS_COUNT_LPIB_DELAY  (1 << 25)	/* Take LPIB as delay */
 #define AZX_DCAPS_PM_RUNTIME	(1 << 26)	/* runtime PM support */
-#define AZX_DCAPS_SUSPEND_SPURIOUS_WAKEUP (1 << 27) /* Workaround for spurious wakeups after suspend */
+/* 27 unused */
 #define AZX_DCAPS_CORBRP_SELF_CLEAR (1 << 28)	/* CORBRP clears itself after reset */
 #define AZX_DCAPS_NO_MSI64      (1 << 29)	/* Stick to 32-bit MSIs */
 #define AZX_DCAPS_SEPARATE_STREAM_TAG	(1 << 30) /* capture and playback use separate stream tag */
@@ -143,6 +143,7 @@  struct azx {
 	unsigned int align_buffer_size:1;
 	unsigned int region_requested:1;
 	unsigned int disabled:1; /* disabled by vga_switcheroo */
+	unsigned int prepared:1;
 
 	/* GTS present */
 	unsigned int gts_present:1;
diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index b4aa1dcf1aae..4cf90e4602c7 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -297,8 +297,7 @@  enum {
 /* PCH for HSW/BDW; with runtime PM */
 /* no i915 binding for this as HSW/BDW has another controller for HDMI */
 #define AZX_DCAPS_INTEL_PCH \
-	(AZX_DCAPS_INTEL_PCH_BASE | AZX_DCAPS_PM_RUNTIME |\
-	 AZX_DCAPS_SUSPEND_SPURIOUS_WAKEUP)
+	(AZX_DCAPS_INTEL_PCH_BASE | AZX_DCAPS_PM_RUNTIME)
 
 /* HSW HDMI */
 #define AZX_DCAPS_INTEL_HASWELL \
@@ -1002,7 +1001,8 @@  static void __azx_runtime_resume(struct azx *chip, bool from_rt)
 	azx_init_pci(chip);
 	hda_intel_init_chip(chip, true);
 
-	if (from_rt) {
+	/* Avoid codec resume if runtime resume is for system suspend */
+	if (from_rt && !chip->prepared) {
 		list_for_each_codec(codec, &chip->bus) {
 			if (codec->relaxed_resume)
 				continue;
@@ -1018,6 +1018,29 @@  static void __azx_runtime_resume(struct azx *chip, bool from_rt)
 }
 
 #ifdef CONFIG_PM_SLEEP
+static int azx_prepare(struct device *dev)
+{
+	struct snd_card *card = dev_get_drvdata(dev);
+	struct azx *chip;
+
+	chip = card->private_data;
+	chip->prepared = 1;
+
+	/* HDA controller always requires different WAKEEN for runtime suspend
+	 * and system suspend, so don't use direct-complete here.
+	 */
+	return 0;
+}
+
+static void azx_complete(struct device *dev)
+{
+	struct snd_card *card = dev_get_drvdata(dev);
+	struct azx *chip;
+
+	chip = card->private_data;
+	chip->prepared = 0;
+}
+
 static int azx_suspend(struct device *dev)
 {
 	struct snd_card *card = dev_get_drvdata(dev);
@@ -1028,14 +1051,7 @@  static int azx_suspend(struct device *dev)
 
 	chip = card->private_data;
 	snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
-	/* An ugly workaround: direct call of __azx_runtime_suspend() and
-	 * __azx_runtime_resume() for old Intel platforms that suffer from
-	 * spurious wakeups after S3 suspend
-	 */
-	if (chip->driver_caps & AZX_DCAPS_SUSPEND_SPURIOUS_WAKEUP)
-		__azx_runtime_suspend(chip);
-	else
-		pm_runtime_force_suspend(dev);
+	__azx_runtime_suspend(chip);
 
 	trace_azx_suspend(chip);
 	return 0;
@@ -1050,11 +1066,7 @@  static int azx_resume(struct device *dev)
 		return 0;
 
 	chip = card->private_data;
-
-	if (chip->driver_caps & AZX_DCAPS_SUSPEND_SPURIOUS_WAKEUP)
-		__azx_runtime_resume(chip, false);
-	else
-		pm_runtime_force_resume(dev);
+	__azx_runtime_resume(chip, false);
 	snd_power_change_state(card, SNDRV_CTL_POWER_D0);
 
 	trace_azx_resume(chip);
@@ -1103,10 +1115,8 @@  static int azx_runtime_suspend(struct device *dev)
 	chip = card->private_data;
 
 	/* enable controller wake up event */
-	if (snd_power_get_state(card) == SNDRV_CTL_POWER_D0) {
-		azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) |
-			   STATESTS_INT_MASK);
-	}
+	azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) |
+		   STATESTS_INT_MASK);
 
 	__azx_runtime_suspend(chip);
 	trace_azx_runtime_suspend(chip);
@@ -1117,18 +1127,15 @@  static int azx_runtime_resume(struct device *dev)
 {
 	struct snd_card *card = dev_get_drvdata(dev);
 	struct azx *chip;
-	bool from_rt = snd_power_get_state(card) == SNDRV_CTL_POWER_D0;
 
 	if (!azx_is_pm_ready(card))
 		return 0;
 	chip = card->private_data;
-	__azx_runtime_resume(chip, from_rt);
+	__azx_runtime_resume(chip, true);
 
 	/* disable controller Wake Up event*/
-	if (from_rt) {
-		azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) &
-			   ~STATESTS_INT_MASK);
-	}
+	azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) &
+		   ~STATESTS_INT_MASK);
 
 	trace_azx_runtime_resume(chip);
 	return 0;
@@ -1162,6 +1169,8 @@  static int azx_runtime_idle(struct device *dev)
 static const struct dev_pm_ops azx_pm = {
 	SET_SYSTEM_SLEEP_PM_OPS(azx_suspend, azx_resume)
 #ifdef CONFIG_PM_SLEEP
+	.prepare = azx_prepare,
+	.complete = azx_complete,
 	.freeze_noirq = azx_freeze_noirq,
 	.thaw_noirq = azx_thaw_noirq,
 #endif