Comment 54 for bug 1256511

https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/1256511/comments/44

the graphic driver seem work at expected, since HDMI/DP,pcm=3 Jack return true when set audio auto / on and return false when set audio off

xrandr --output HDMI --set audio auto

xrandr --output HDMI --set audio on

control.42 {
  iface CARD
  name 'HDMI/DP,pcm=3 Jack'
  value true
  comment {
   access read
   type BOOLEAN
   count 1
  }
 }

 control.47 {
  iface PCM
  device 3
  name ELD
  value '100008006712000100000000000000004c2d020953414d53554e470907070000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000'
  comment {
   access 'read volatile'
   type BYTES
   count 83
  }
 }

xrandr --output HDMI --set audio off

control.42 {
  iface CARD
  name 'HDMI/DP,pcm=3 Jack'
  value false
  comment {
   access read
   type BOOLEAN
   count 1
  }
 }

 control.47 {
  iface PCM
  device 3
  name ELD
  value ''
  comment {
   access 'read volatile'
   type BYTES
   count 0
  }
 }