Hi!
On ASUS ROG G751 laptops the heaphone port is mapped to nothing, causing it to not function at all. I propose that we add a remap of pin 0x16 to Headphone in order to prevent this issue, and fix compability with the new mode=asus-g751.
I don't know how to write patches, but this is what needs adding in sound/pci/hda/patch_realtek.c:
[ALC668_FIXUP_ASUS_G751_PINS] = { .type = HDA_FIXUP_PINS, .v.pins = (const struct hda_pintbl[]) { { 0x16, 0x0421101f }, /* HP */ {} }, }, [ALC668_FIXUP_ASUS_G751] = { .type = HDA_FIXUP_VERBS, .v.verbs = (const struct hda_verb[]) { { 0x20, AC_VERB_SET_COEF_INDEX, 0xc3 }, { 0x20, AC_VERB_SET_PROC_COEF, 0x4000 }, {} }, .chained = true, .chain_id = ALC668_FIXUP_ASUS_G751_PINS },
And declaring the function earlier.
-Håvard