[PATCH 4.4 08/46] ALSA: hda: fix a runtime pm issue in SOF when integrated GPU is disabled

From: Greg Kroah-Hartman
Date: Mon Sep 21 2020 - 12:33:12 EST

From: Rander Wang <rander.wang@xxxxxxxxx>

[ Upstream commit 13774d81f38538c5fa2924bdcdfa509155480fa6 ]

In snd_hdac_device_init pm_runtime_set_active is called to
increase child_count in parent device. But when it is failed
to build connection with GPU for one case that integrated
graphic gpu is disabled, snd_hdac_ext_bus_device_exit will be
invoked to clean up a HD-audio extended codec base device. At
this time the child_count of parent is not decreased, which
makes parent device can't get suspended.

This patch calls pm_runtime_set_suspended to decrease child_count
in parent device in snd_hdac_device_exit to match with
snd_hdac_device_init. pm_runtime_set_suspended can make sure that
it will not decrease child_count if the device is already suspended.

Signed-off-by: Rander Wang <rander.wang@xxxxxxxxx>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@xxxxxxxxxxxxxxx>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
Reviewed-by: Bard Liao <yung-chuan.liao@xxxxxxxxxxxxxxx>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@xxxxxxxxxxxxxxx>
Signed-off-by: Kai Vehmanen <kai.vehmanen@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20200902154218.1440441-1-kai.vehmanen@xxxxxxxxxxxxxxx
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
sound/hda/hdac_device.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/sound/hda/hdac_device.c b/sound/hda/hdac_device.c
index e361024eabb63..020ec48f39048 100644
--- a/sound/hda/hdac_device.c
+++ b/sound/hda/hdac_device.c
@@ -123,6 +123,8 @@ EXPORT_SYMBOL_GPL(snd_hdac_device_init);
void snd_hdac_device_exit(struct hdac_device *codec)
+ /* keep balance of runtime PM child_count in parent device */
+ pm_runtime_set_suspended(&codec->dev);
snd_hdac_bus_remove_device(codec->bus, codec);