[PATCH AUTOSEL 5.6 12/38] ALSA: hda: Skip controller resume if not needed

Sasha Levin
2020-04-24T12:22:59Z

From: Takashi Iwai <tiwai@suse.de>

[ Upstream commit c4c8dd6ef807663e42a5f04ea77cd62029eb99fa ]

The HD-audio controller does system-suspend and resume operations by
directly calling its helpers __azx_runtime_suspend() and
__azx_runtime_resume(). However, in general, we don't have to resume
always the device fully at the system resume; typically, if a device
has been runtime-suspended, we can leave it to runtime resume.

Usually for achieving this, the driver would call
pm_runtime_force_suspend() and pm_runtime_force_resume() pairs in the
system suspend and resume ops. Unfortunately, this doesn't work for
the resume path in our case. For handling the jack detection at the
system resume, a child codec device may need the (literally) forcibly
resume even if it's been runtime-suspended, and for that, the
controller device must be also resumed even if it's been suspended.

This patch is an attempt to improve the situation. It replaces the
direct __azx_runtime_suspend()/_resume() calls with with
pm_runtime_force_suspend() and pm_runtime_force_resume() with a slight
trick as we've done for the codec side. More exactly:

- azx_has_pm_runtime() check is dropped from azx_runtime_suspend() and
azx_runtime_resume(), so that it can be properly executed from the
system-suspend/resume path

- The WAKEEN handling depends on the card's power state now; it's set
and cleared only for the runtime-suspend

- azx_resume() checks whether any codec may need the forcible resume
beforehand. If the forcible resume is required, it does temporary
PM refcount up/down for actually triggering the runtime resume.

- A new helper function, hda_codec_need_resume(), is introduced for
checking whether the codec needs a forcible runtime-resume, and the
existing code is rewritten with that.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=207043
Link: https://lore.kernel.org/r/20200413082034.25166-6-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
include/sound/hda_codec.h | 5 +++++
sound/pci/hda/hda_codec.c | 2 +-
sound/pci/hda/hda_intel.c | 38 +++++++++++++++++++++++++++-----------
3 files changed, 33 insertions(+), 12 deletions(-)

diff --git a/include/sound/hda_codec.h b/include/sound/hda_codec.h
index 3ee8036f5436d..225154a4f2ed0 100644
--- a/include/sound/hda_codec.h
+++ b/include/sound/hda_codec.h
@@ -494,6 +494,11 @@ void snd_hda_update_power_acct(struct hda_codec *codec);
static inline void snd_hda_set_power_save(struct hda_bus *bus, int delay) {}
#endif

+static inline bool hda_codec_need_resume(struct hda_codec *codec)
+{
+ return !codec->relaxed_resume && codec->jacktbl.used;
+}
+
#ifdef CONFIG_SND_HDA_PATCH_LOADER
/*
* patch firmware
diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
index 53e7732ef7520..aed1f8188e662 100644
--- a/sound/pci/hda/hda_codec.c
+++ b/sound/pci/hda/hda_codec.c
@@ -2951,7 +2951,7 @@ static int hda_codec_runtime_resume(struct device *dev)
static int hda_codec_force_resume(struct device *dev)
{
struct hda_codec *codec = dev_to_hda_codec(dev);
- bool forced_resume = !codec->relaxed_resume && codec->jacktbl.used;
+ bool forced_resume = hda_codec_need_resume(codec);
int ret;

/* The get/put pair below enforces the runtime resume even if the
diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index aa0be85614b6c..02c6308502b1e 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -1027,7 +1027,7 @@ static int azx_suspend(struct device *dev)
chip = card->private_data;
bus = azx_bus(chip);
snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
- __azx_runtime_suspend(chip);
+ pm_runtime_force_suspend(dev);
if (bus->irq >= 0) {
free_irq(bus->irq, chip);
bus->irq = -1;
@@ -1044,7 +1044,9 @@ static int azx_suspend(struct device *dev)
static int azx_resume(struct device *dev)
{
struct snd_card *card = dev_get_drvdata(dev);
+ struct hda_codec *codec;
struct azx *chip;
+ bool forced_resume = false;

if (!azx_is_pm_ready(card))
return 0;
@@ -1055,7 +1057,20 @@ static int azx_resume(struct device *dev)
chip->msi = 0;
if (azx_acquire_irq(chip, 1) < 0)
return -EIO;
- __azx_runtime_resume(chip, false);
+
+ /* check for the forced resume */
+ list_for_each_codec(codec, &chip->bus) {
+ if (hda_codec_need_resume(codec)) {
+ forced_resume = true;
+ break;
+ }
+ }
+
+ if (forced_resume)
+ pm_runtime_get_noresume(dev);
+ pm_runtime_force_resume(dev);
+ if (forced_resume)
+ pm_runtime_put(dev);
snd_power_change_state(card, SNDRV_CTL_POWER_D0);

trace_azx_resume(chip);
@@ -1102,12 +1117,12 @@ static int azx_runtime_suspend(struct device *dev)
if (!azx_is_pm_ready(card))
return 0;
chip = card->private_data;
- if (!azx_has_pm_runtime(chip))
- return 0;

/* enable controller wake up event */
- azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) |
- STATESTS_INT_MASK);
+ if (snd_power_get_state(card) == SNDRV_CTL_POWER_D0) {
+ azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) |
+ STATESTS_INT_MASK);
+ }

__azx_runtime_suspend(chip);
trace_azx_runtime_suspend(chip);
@@ -1118,17 +1133,18 @@ 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;
- if (!azx_has_pm_runtime(chip))
- return 0;
- __azx_runtime_resume(chip, true);
+ __azx_runtime_resume(chip, from_rt);

/* disable controller Wake Up event*/
- azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) &
- ~STATESTS_INT_MASK);
+ if (from_rt) {
+ azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) &
+ ~STATESTS_INT_MASK);
+ }

trace_azx_runtime_resume(chip);
return 0;
--
2.20.1