Lenovo M70/M90 Gen4 are equipped with ALC897, and they need ALC897_FIXUP_HEADSET_MIC_PIN quirk to make its headset mic work. The previous quirk for M70/M90 is for Gen3.
Lenovo M70/M90 Gen4 are equipped with ALC897, and they need FIXUP_HEADSET_ MIC_PIN quirk to make its headset mic work.
ALC897_
The previous quirk for M70/M90 is for Gen3.