Initially the ATI R600 GPUs and later with the available open-source drivers (
xf86-video-ati and
xf86-video-radeonhd) hadn't supported using the graphics card's integrated audio processor with
HDMI output. An end-user though dissatisfied with this had went on to reverse-engineer the support for
RadeonHD HDMI audio support. The audio patch was then
merged to master within the last two weeks that now enable ATI HDMI audio output support with that open-source driver.
Those using
Intel's driver with the G35 or
G45 series have too been without HDMI audio capabilities. Intel though has now stepped up to the plate and have sent along patches that enable this capability.
Intel's Wu Fengguang has posted three patches on the X.Org mailing list that bring forward this support (
one,
two, and
three). A patch has also been posted on
the mailing list for the
ALSA (Advanced Linux Sound Architecture) to support the audio codec with Intel's G45 and to report the monitor's ELD (EDID-Like Data).
These patches haven't yet made their way into the respective xf86-video-intel and ALSA driver development branches, but we imagine they will be soon.