ALSA: hda - Protect the power-saving count with spinlock
To avoid some races. Still not perfect, but now a bit safer.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
index 8bd3432..30a3d8f 100644
--- a/sound/pci/hda/hda_codec.c
+++ b/sound/pci/hda/hda_codec.c
@@ -1266,6 +1266,7 @@
snd_array_init(&codec->spdif_out, sizeof(struct hda_spdif_out), 16);
#ifdef CONFIG_SND_HDA_POWER_SAVE
+ spin_lock_init(&codec->power_lock);
INIT_DELAYED_WORK(&codec->power_work, hda_power_work);
/* snd_hda_codec_new() marks the codec as power-up, and leave it as is.
* the caller has to power down appropriatley after initialization
@@ -4292,12 +4293,16 @@
container_of(work, struct hda_codec, power_work.work);
struct hda_bus *bus = codec->bus;
+ spin_lock(&codec->power_lock);
if (!codec->power_on || codec->power_count) {
codec->power_transition = 0;
+ spin_unlock(&codec->power_lock);
return;
}
trace_hda_power_down(codec);
+ spin_unlock(&codec->power_lock);
+
hda_call_codec_suspend(codec);
if (bus->ops.pm_notify)
bus->ops.pm_notify(bus);
@@ -4305,9 +4310,11 @@
static void hda_keep_power_on(struct hda_codec *codec)
{
+ spin_lock(&codec->power_lock);
codec->power_count++;
codec->power_on = 1;
codec->power_jiffies = jiffies;
+ spin_unlock(&codec->power_lock);
}
/* update the power on/off account with the current jiffies */
@@ -4332,20 +4339,28 @@
{
struct hda_bus *bus = codec->bus;
+ spin_lock(&codec->power_lock);
codec->power_count++;
- if (codec->power_on || codec->power_transition)
+ if (codec->power_on || codec->power_transition) {
+ spin_unlock(&codec->power_lock);
return;
+ }
trace_hda_power_up(codec);
snd_hda_update_power_acct(codec);
codec->power_on = 1;
codec->power_jiffies = jiffies;
codec->power_transition = 1; /* avoid reentrance */
+ spin_unlock(&codec->power_lock);
+
if (bus->ops.pm_notify)
bus->ops.pm_notify(bus);
hda_call_codec_resume(codec);
+
+ spin_lock(&codec->power_lock);
cancel_delayed_work(&codec->power_work);
codec->power_transition = 0;
+ spin_unlock(&codec->power_lock);
}
EXPORT_SYMBOL_HDA(snd_hda_power_up);
@@ -4361,14 +4376,18 @@
*/
void snd_hda_power_down(struct hda_codec *codec)
{
+ spin_lock(&codec->power_lock);
--codec->power_count;
- if (!codec->power_on || codec->power_count || codec->power_transition)
+ if (!codec->power_on || codec->power_count || codec->power_transition) {
+ spin_unlock(&codec->power_lock);
return;
+ }
if (power_save(codec)) {
codec->power_transition = 1; /* avoid reentrance */
queue_delayed_work(codec->bus->workq, &codec->power_work,
msecs_to_jiffies(power_save(codec) * 1000));
}
+ spin_unlock(&codec->power_lock);
}
EXPORT_SYMBOL_HDA(snd_hda_power_down);