[V3] vga_switcheroo: set audio client id according to bound GPU id

[Lukas Wunner]

On Tue, Jul 17, 2018 at 04:20:50PM +0800, Jim Qu wrote:
> On modern laptop, there are more and more platforms
> have two GPUs, and each of them maybe have audio codec
> for HDMP/DP output. For some dGPU which is no output,
> audio codec usually is disabled.
> 
> In currect HDA audio driver, it will set all codec as
> VGA_SWITCHEROO_DIS, the audio which is binded to UMA
> will be suspended if user use debugfs to contorl power
> 
> In HDA driver side, it is difficult to know which GPU
> the audio has binded to. So set the bound gpu pci dev
> to vga_switcheroo.
> 
> if the audio client is not the third registration, audio
> id will set in vga_switcheroo enable function. if the
> audio client is the last registration when vga_switcheroo
> _ready() get true, we should get audio client id from bound
> GPU directly.
> 
> Signed-off-by: Jim Qu <Jim.Qu at amd.com>

Reviewed-by: Lukas Wunner <lukas at wunner.de>

@Takashi, any preference which tree to merge this through?
sound or drm-misc, either way would seem fine to me.  I think
there's going to be one final drm-misc pull sent to Dave this
week, after that it's 4.20.

Thanks,

Lukas