• Stephen Warren's avatar
    ALSA: hda: Virtualize SPDIF out controls · 74b654c9
    Stephen Warren authored
    The SPDIF output controls apply to converter widgets. A future change
    will create a PCM device per pin widget, and hence a set of SPDIF output
    controls per pin widget, for certain HDMI codecs. To support this, we
    need the ability to virtualize the SPDIF output controls. Specifically:
    * Controls can be "unassigned" from real hardware when a converter is
      not used for the PCM the control was created for.
    * Control puts only write to hardware when they are assigned.
    * Controls can be "assigned" to real hardware when a converter is picked
      to support output for a particular PCM.
    * When a converter is assigned, the hardware is updated to the cached
    Signed-off-by: Stephen Warren's avatarStephen Warren <swarren@nvidia.com>
    Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>