At Tue, 12 Mar 2013 16:05:26 +1000, Dave Airlie wrote:
Hey guys,
I've been writing dynamic power management code for the secondary GPUs, however a lot of these GPUs have audio codecs as a subfunction PCI device.
So we get 01:00.0 as the GPU and 01:00.1 as the HDMI audio device.
Now we have a single power switch for these devices, and generally the power switch is hit when the ACPI entry to D3 is called for the GPU and it shuts off the whole device.
So the problem I'm having is how to have the audio device (snd_hda_intel), understand that it needs to have the GPU devices D0 called before it can do its own D0, and thats its D3 should be called before the GPU drivers D3.
Any pointers? Do I need to create a separate pm domain for these devices? how does the ordering work then?
Implementing pm_domain in both graphics and audio drivers, graphics as a mater and audio a slave?
Takashi