[PATCH AUTOSEL 5.3 004/203] ALSA: hda/hdmi - Don't report spurious jack state changes

From: Sasha Levin
Date: Sun Sep 22 2019 - 15:39:31 EST


From: Takashi Iwai <tiwai@xxxxxxx>

[ Upstream commit 551626ec0ad28dc43cae3094c35be7088cc625ab ]

The HDMI jack handling reports the state change always via
snd_jack_report() whenever hdmi_present_sense() is called, even if the
state itself doesn't change from the previous time. This is mostly
harmless but still a bit confusing to user-space.

This patch reduces such spurious jack state changes and reports only
when the state really changed. Also, as a minor optimization, avoid
overwriting the pin ELD data when the state is identical.

Reviewed-by: Kai Vehmanen <kai.vehmanen@xxxxxxxxxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
sound/pci/hda/patch_hdmi.c | 32 ++++++++++++++++++--------------
1 file changed, 18 insertions(+), 14 deletions(-)

diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
index bea7b09610809..c380596b2e84c 100644
--- a/sound/pci/hda/patch_hdmi.c
+++ b/sound/pci/hda/patch_hdmi.c
@@ -1421,7 +1421,7 @@ static void hdmi_pcm_reset_pin(struct hdmi_spec *spec,
/* update per_pin ELD from the given new ELD;
* setup info frame and notification accordingly
*/
-static void update_eld(struct hda_codec *codec,
+static bool update_eld(struct hda_codec *codec,
struct hdmi_spec_per_pin *per_pin,
struct hdmi_eld *eld)
{
@@ -1452,18 +1452,22 @@ static void update_eld(struct hda_codec *codec,
snd_hdmi_show_eld(codec, &eld->info);

eld_changed = (pin_eld->eld_valid != eld->eld_valid);
- if (eld->eld_valid && pin_eld->eld_valid)
+ eld_changed |= (pin_eld->monitor_present != eld->monitor_present);
+ if (!eld_changed && eld->eld_valid && pin_eld->eld_valid)
if (pin_eld->eld_size != eld->eld_size ||
memcmp(pin_eld->eld_buffer, eld->eld_buffer,
eld->eld_size) != 0)
eld_changed = true;

- pin_eld->monitor_present = eld->monitor_present;
- pin_eld->eld_valid = eld->eld_valid;
- pin_eld->eld_size = eld->eld_size;
- if (eld->eld_valid)
- memcpy(pin_eld->eld_buffer, eld->eld_buffer, eld->eld_size);
- pin_eld->info = eld->info;
+ if (eld_changed) {
+ pin_eld->monitor_present = eld->monitor_present;
+ pin_eld->eld_valid = eld->eld_valid;
+ pin_eld->eld_size = eld->eld_size;
+ if (eld->eld_valid)
+ memcpy(pin_eld->eld_buffer, eld->eld_buffer,
+ eld->eld_size);
+ pin_eld->info = eld->info;
+ }

/*
* Re-setup pin and infoframe. This is needed e.g. when
@@ -1481,6 +1485,7 @@ static void update_eld(struct hda_codec *codec,
SNDRV_CTL_EVENT_MASK_VALUE |
SNDRV_CTL_EVENT_MASK_INFO,
&get_hdmi_pcm(spec, pcm_idx)->eld_ctl->id);
+ return eld_changed;
}

/* update ELD and jack state via HD-audio verbs */
@@ -1582,6 +1587,7 @@ static void sync_eld_via_acomp(struct hda_codec *codec,
struct hdmi_spec *spec = codec->spec;
struct hdmi_eld *eld = &spec->temp_eld;
struct snd_jack *jack = NULL;
+ bool changed;
int size;

mutex_lock(&per_pin->lock);
@@ -1608,15 +1614,13 @@ static void sync_eld_via_acomp(struct hda_codec *codec,
* disconnected event. Jack must be fetched before update_eld()
*/
jack = pin_idx_to_jack(codec, per_pin);
- update_eld(codec, per_pin, eld);
+ changed = update_eld(codec, per_pin, eld);
if (jack == NULL)
jack = pin_idx_to_jack(codec, per_pin);
- if (jack == NULL)
- goto unlock;
- snd_jack_report(jack,
- (eld->monitor_present && eld->eld_valid) ?
+ if (changed && jack)
+ snd_jack_report(jack,
+ (eld->monitor_present && eld->eld_valid) ?
SND_JACK_AVOUT : 0);
- unlock:
mutex_unlock(&per_pin->lock);
}

--
2.20.1