[SRU][B/OEM-B/C/D][PATCH 0/3] repeating crackling noise happens after 19.04 upgrade

[Hui Wang]

BugLink: https://bugs.launchpad.net/bugs/1821663

This is because the kernel config CONFIG_SND_HDA_POWER_SAVE_DEFAULT is changed to
1 in the recent disco kernel.

I also backported the patch to cosmic and bionic since this patch is harmless to
cosmic and bionic.

For Disco kernel, we only need 1 patch. Because of patch conflicting, cosmic
kernel needs 2 patches and bionic kernel needs 3 patches.

[Impact]
After CONFIG_SND_HDA_POWER_SAVE_DEFAULT is changed to 1, the codec runtime PM is
enabled, on some codecs or for some hw design, there is noise with the codec
runtime PM enabled.


[Fix]
put the machine in the power_save_black_list, this will set the power_save=0

[Test Case]
just boot up and do some audio operations, there is no noise anymore

[Regression Risk]
Low. this patch ony applies to the specific machines.



Hans de Goede (1):
  ALSA: hda: Add Intel NUC7i3BNB to the power_save blacklist

Hui Wang (1):
  ALSA: hda - Add two more machines to the power_save_blacklist

Jaroslav Kysela (1):
  ALSA: hda - add Lenovo IdeaCentre B550 to the power_save_blacklist

 sound/pci/hda/hda_intel.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

-- 
2.17.1