[alsa-devel] [V2 2/2] vgaswitchreoo: set audio client id in vgaswitchreoo enable function

[Lukas Wunner]

On Mon, Jul 16, 2018 at 03:52:45PM +0800, Hui Wang wrote:
> On 2018???07???16??? 14:06, 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 control power
> >
> >In HDA driver side, it is difficult to know which GPU
> >the audio has bound to. So set the bound gpu pci dev
> >to vgaswitchreoo, the correct audio id will be set in
> >vgaswitchreoo enable function.
> >
> >Signed-off-by: Jim Qu <Jim.Qu at amd.com>
> 
> Is it possible to send this patch to <stable at vger.kernel.org> as well, then
> we will know that it is safe to backport this patch to the linux kernels
> with different version.

For which hardware do you want it in stable kernels?

This patch pertains to manual power control, which is only used on the
MacBook Pro by default.  And there are no MacBook Pros with AMD APUs.
On all other hardware, users have to specify "amdgpu.runpm=0" on the
command line to see any benefit from this patch.  Also, manual power
control will likely be removed once we get runtime PM working with
muxed systems (such as the MacBook Pro).

Lukas