Comment 49 for bug 1252733

if hardware cannot distinguish headset and headphone

does this mean that the function if the Jack is determined by capture source ?

internal Mic = headphone
headset Mic = headset
headphone Mic = mic

control.10 {
   iface MIXER
   name 'Capture Source'
   value 'Internal Mic'
   comment {
    access 'read write'
    type ENUMERATED
    count 1
    item.0 'Headphone Mic'
    item.1 'Headset Mic'
    item.2 'Internal Mic'
   }
  }

if you only use headset and want automic when you plugged in
you need to giveup the support of Mic jack and headphone by a new hint which change the logic

https://bugs.freedesktop.org/show_bug.cgi?id=81580