snd_hdac_link_power() has to be called after unregistering the codec device. Otherwise the device might be already runtime-suspended, thus the refcount goes under zero, triggering a warning like:
WARNING: CPU: 7 PID: 2014 at sound/hda/hdac_i915.c:63 snd_hdac_display_power+0x106/0x120 [snd_hda_core]() CPU: 7 PID: 2014 Comm: modprobe Not tainted 4.1.0-rc7-test+ #1 Call Trace: [<ffffffff81697fe3>] dump_stack+0x4c/0x6e [<ffffffff810696da>] warn_slowpath_common+0x8a/0xc0 [<ffffffff810697ca>] warn_slowpath_null+0x1a/0x20 [<ffffffffa02dd526>] snd_hdac_display_power+0x106/0x120 [snd_hda_core] [<ffffffffa030b422>] azx_intel_link_power+0x12/0x20 [snd_hda_intel] [<ffffffffa037139f>] azx_link_power+0x1f/0x30 [snd_hda_codec] [<ffffffffa02d89fe>] snd_hdac_link_power+0x2e/0x40 [snd_hda_core] [<ffffffffa0368524>] snd_hda_codec_dev_free+0x34/0x50 [snd_hda_codec] [<ffffffffa0252061>] __snd_device_free+0x51/0xa0 [snd] .....
Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/pci/hda/hda_codec.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c index d70229841156..497bd0f9dcda 100644 --- a/sound/pci/hda/hda_codec.c +++ b/sound/pci/hda/hda_codec.c @@ -886,8 +886,8 @@ static int snd_hda_codec_dev_free(struct snd_device *device) struct hda_codec *codec = device->device_data;
codec->in_freeing = 1; - snd_hdac_link_power(&codec->core, false); snd_hdac_device_unregister(&codec->core); + snd_hdac_link_power(&codec->core, false); put_device(hda_codec_dev(codec)); return 0; }