http://git.kernel.org/cgit/linux/kernel/git/tiwai/sound.git/commit/?id=e4db0952e542090c605fd41d31d761f1b4624f4a
seem other ideapad also use same PCI SSID 17aa:3977
http:// git.kernel. org/cgit/ linux/kernel/ git/tiwai/ sound.git/ commit/ ?id=e4db0952e54 2090c605fd41d31 d761f1b4624f4a
seem other ideapad also use same PCI SSID 17aa:3977